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MAMCH 

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uBAAfves 




06905998 



8641^>:i 



PREFACE. 



yean barv now clcpsed naoe thia Mtgaxine first made its u^pesrwace. It has 
throagbrmt with care and mergy, Bud the uadiminisbed, oay increaMog 
it, w the hot crideaoe that oar endeavoars haTc met with approbalioa. 

Ilii* oontinoed proepcrUy of our uDABptnug little work caxioot be attnbuico lo lor- 
itoam circtunetanoee. The year of Uie pabboition of our lint volume, uideed« wm 
tmlmred Sd hy fsn^ endden, and imezpectcd diacovvriea in scicuee and art— Fhot< 

and the Daguerrcotrpe beiog among them. The aeeood Tolume, in Hke manner, 
•imnltaoAOiu with the Electro-type, Electro-magDetio movements of varioni 
<>ther oquanjr inteiTHtiag matters. The last ^nenTr oo the oontrory, has beeo 

in 4kcovme*. Hie meeting of the BhtiAh Association waa admittedly a hHure 

HiOvftl Society haa prodoced nothing o^ interest; the Philosophiciil Periudicols hai 

ino^ aAfraicful ; Mcehaaica] and Manufiictimng gemua has invooted little of pubti 

tano« ; the huasted German and Ruasian Electro-magnetie Machines are decided 

; and even the Acadetme des ScMOoes at Paris, that b genenlly «o mnch on 

mlert in mctcn of discovery, has been vapid and uninteresting. 

With bB tbeae discouraging eirenmstancca* attended by a complete stagnation nnd 

<t in the book trade, BtiQ we have steadily pursued our wonted course; and U it 

-NhtioA to reflect upon the steady support we b&ve contintially received from 

iuyrrj thmg new and really vihiablo we have maerted. and every thing, 

Tiuhiie iaquhy we have cvpltuned. Yet should our Friends have seen vttcli 

i«giaarr isventtonit in the public papers, tiui wondin^d why thoee aitictca faaive^ 

• - — 

d with na ; we can tell them, that paragrapbs in Works which ore iuA aciicntific 

>iys to be depended upon, thus we should oftcjitimes quote, and have tmmediAtaty 

to contradict. If such accounts are true in themsehrea, it^ is impoaaible that 

'tt timea procure the iniurmiitiun refinlsite to muke th^g^valuahlc'; inveotore kee^i 



7 ^^.iZi'aCE 

E'ttf"".-. '-.'^ ■- ■-. '.h«.rc are sor- c art.-? which we tc-x ibtu*!» Uttlc icfonaiitia:; is^ no ^v 
f .ctcry .Lcc'.'ii' 'jfin?" puM'-ihcd in our la:i</!r.LT ; for ejifamplc. Turaing, Orgwi Baiidaiir. 
■u:'i Acr^'^raphy. 

As fiir, however, ab tlie abov.; a't- are conrtrnci, ar.d s^me more, of wtijcb we hav;; 
rot iii'herto rreut; :i , wi: tj^ in wtli-ijroiiaded cxpcctoaon,. very k>oq, of rrc»ci:ring 
the tl-.-'^ei i.'ifurn .ition upoi., as wc!' a« of nunicrous otiitrs of more scncial intirvst, 
l)yeiii£r, oicacl'inp. Tli'jrmo-ma^etifna, &c. ; thus we Ir.ve do hesitation ia proir.i^ing 
iccrca-'j 'f H.*i:re»T to ci.r r/:xt vulunif. One ^re&t . iteration which we inttnc toi-.".pl 
i-. f- crii-T f. iricl>iri»'. into the b-xij of tht- text a srcat part cf the answers to Corr>:.-=p-i ii- 
<'"-rjt>, iio- tin-: ■ i. -Mr jnquiriefr in the ^-hapi: of queries, and sjiswering them a= Pi*xh, I -.;vii jr 
T^ . our 01*1*- ! Corrcsp'.mdents to send as other and better answers, if they can, as in tlio 'irel 
■vviiurue. 

The mo't pleasing duty still remains fur w= ; it is to tliaak those who have WindJr 
•. .ritnij.iV-ti iij!'».rn'-ition to our pairvs. Tu iiami; particiilar individuals would bo inV)iii»"*u?, 

• ■- coui.i w a-dicml^cr th^ra all; and imju^t did we not also express our scnu »•: 

• '■•':»,' :i^'. M t'- (ji,r norncrou- :itfn iuoiir I'rKud.-. 

'Ac IpJIcvc liiat wc hitve ancwcrtu idj letter^; received throucrhout the year, yet thc;5e 

• -. n.' h:ivt- Ijttn ail winch have l)t;ti. ficni to \xs\ foi while Currespondcnta wmd their 
:■ >:i !i'ii»!-;uiifinr. -lonic to the rubli-iitr, uthtrfc to the Printer, others even to our urmtr 

• - ; .i,'.. ':«.!••( vvliwrh v.L- iiuvt> now left for nmny moiithfe,) it is pet^sible, particularly in tlic 
'-.tU;r '•■.-/_', 'ill ' ;-.«iinc (.f Ihcrti Imve been di.lnvcd ui iust. 



THE EDlTOit. 



1 ,-'\ /. Hf^- 



THE 



AGAZINE OF SCIENCE 



^nb ^rtiool of ^r($(. 



\5J] 



8.\TL'RUAY AI'iUL. a. IMl. 



IHd. 




THREE-WHEELED ORRERY. 
Tb the Editor. 

Km.^l indoM for itiM-rtioii tn ^our Mnguini;, a 
|icrsprt:livc riew of the exttrnal arranK^iiiKrit of a 
three-wheeled orrery, which 1 invented iluihig my 
raideocc in Loudon, early in the year 1H37> 

The wheel-work, Ac, U inclo»«l witUiu a large 
oircnlnr frame of maliogany, of about eighteen inclica 
is diaraeter, E E, on the upper surface of which is 
carefully laid down the signu of the elliptic — the 
days cif the inontti, and hourf of tlic (&y. as de- 
lineated. The aim is repriMentcd by a ball, S, in 
the centre, ^Ided, and is six inches in diameter, to 
the right of wliich ia a small terreatlal globe, F, 
tiin* inrhcs in diameter, on wbitth are engravcji the 
■cTeml countrira of the world, with circles of lali- 
todr and longitude, and i» fiurmanded with a small 
engniTcn ecliptic circlf, K, and circle of altitude, L. 
The IniII, E, repri'$entiiii|; the earth, is iiirlmed at aa 
angle of aboat 23^", and is attachitl to on axle 
which asceoda from the wheeUwurk, and by virtue 
of which connexion it prraerrcs its parallcliam in \ta 
circular journey round' the- win, thereby familiarly 
^Ifthibiting the cafise of the rhonf^e of the scaMma< 
■nd differont tengthi of day and night throughout 
the year, &c. Immediately under the earth i« fixed 
a small circular dial-plate, on which i^ engraven the 
twciity-four tioori of day and night, which ie very 
■ervicesbtc in attaiuing the time of terrc^tial phe- 
iMnnena. Under Ibis dial-plMe i« another, which ia 
atationary, and on wliich arc rrigniTen the daytt of 
the moon's age ; and lastly, another circle is attache*! 
tb the wheel-wnrk, and on which is laid dnwn the 
dcgreoi. Stc. of the node:* of the nioon'i orbit. This 
rfng or circle is inclined at an an^lc of about 5^"^ 
to the plane of the frame, E E. Thia ring has a 
retrograde motion in the ecliptic in the space of 
18 years and 234 dnys, which is nearly the ptiriod of 
the nodes. Between the circles of the hour, at the 
foot of the earth's axis, and the circle of tlic moon's 
age, a horizontal arm extends from the wheel-work, 
and carrteH a [wrpendicular arm, H, which is partly 
hnUow, for tlie pnrpoitc of affording a vcTtical motion 
mitable to the mooD'tt dceliiuilion, ike. M is a small 
boll of about thrce.quartera of on inch in diameter, 
and is furnifitied with a black cap. which exactly 
covers from view one-half <if tJu* lunar globe, and to 
which is attached a kind of forked arm cxti-iiding 
upwards, and has a comirxion with the sun tliruugh 
the medium of tlie slight horizontal bar^ Vi, and 
joined to tlie sun at 1. In short, with this very 
simple orrery, the following vrr^- interesting astro- 
nomieal phenomena may be dif^tinctly ascwrtained, 
and which, so far as I know, U the first time such 
important results from such simple causes have been 
effected : — 

Phenomena a-hidifed by tht Neuf OrrHy* 
r. — The ime(|UBl lengths of day and njglit durinj^ 
the year, and hence the cause of the %'iciiwitudji 
of the seaaons. 
2. — The fun's place in the ecliptic, declination, Ac. 
S. — Tb« periodic and synodic revolution of the moon. 
4. — The moon's iliumal mtation on its axis. 
4. — Tlie aff)? and phases of the moon. 
8.— The morion of the moon's orbit. 
7. — Tlie motion of the apogee of moon's orbit. 
S.-^Tlif eclipttes of the sun, moon, &c. 

All the above being efiVetcd by a very peculiar 

WT'tngpmeqt of only three wheels and a pinion. I may 

«M th«t the moon goes roond the earth in the ma- 



chine in 29 days. 12 houn, 14 miiuitrs, 2^i M>randil. 
and romul its own axil in the same time. The eartli 
is moved by hand, ts aastuued to perform its journey 
niuiid the unn in^GAdays, 5 hours, 4B minutcff. nnd 
9 seconds. The moon's orbit makes a rrtrograilt? 
movement through all the sixns and drgrces iif tlie 
great ecliptic cirdc in G,7^B days, 1^ hours, aul 
that of the apogee iu 3,231 days, 18 houn. tn^tfat 
time. 

I gmerally exhilitt this simple orrery inmrutro^ 
nomieal lectures, and as it ^ves general satisfaetianr 
and as a number wish to have copies of its form* I 
send it to you, in mxler that (bey may see it engrnvtM) 
in ynur widely -circulated Magazine, of which 1 have 
b«en a subftcriber since* its commenctmient. 1 may« 
at farm future period, render you a description of 
the wheel-work of thlR instromcnt, as also of ■ 
variety of original aiift various aatronomiral ma- 
chinery, should the present be acceptable to yonr 
readers. s. uknoebsox. 



IMPROVEMENT OF THE DAGUERREO- 
TYPE. 
Till process of Mr. Wolcroft, an American, paj- 
tented in Englnnd by Mr. Beard, for quickening 
the acliim of tlte Daguerreotype, so a» to produce 
the eflVct in a few seconds, ia now carried intft 
practice at the Polytechnic Institution in taVing 
likenesses. The mom titted up for the pnrpofle Is 
at the top of the building in CaTcndish-aquare. 
Tlie roof is composed for the most part of Urge 
sheets of jtlate-gla^^, $tnined blue to soften the light, 
and this glois ruohng traverses so as to meet llie 
rays of tlie sun nt any part of the day. The sitter 
is placed on an elevated platform, with a support 
for the head, snd the camera obscura rests on ■ 
shelf ■ few feef distance from him. The constnie- 
tion of the cnmera itself, as thus applied, consti- 
tntea part of Mr. Wolcrofl's patent. Instead of 
using a lens to refract the rays of light to a focoe, 
he empIbjR a reflector, ahout seven inches diametef« 
By this means a much greater number of the rays 
issuing from the object are concentrated within • 
given space than could be otherwise accomplished, 
and the image is consequently the brighter. The 
speculum may abo be placed nearer to catch thfi 
rays of light than a lens, and this also affords aa 
additional increase of collected rays in the image. 
Tlie silvered plate, prepared with a coating of thft 
vajiors produced by iodine mixed with nitric aeidt 
or with bromine, so aa to quicken the action of tha 
light, is put into the focus of the reflecting mirror. 
The person whose likeness is to be taken keeps Mia 
face steady for a few seconds, and the effect on the 
iodine coating iiit produced. The plate is then taken 
away, and excluded carefully from the light until it 
has been exposed to the vapor of mercury, which 
sttacbea to the parts acted on by the tight, and the 
image becomes visible — a perfect fac-aimile of nature. 
Before the plate is exposed to the light, the iedine 
if washed off, and all farther cliooge is thus pre- 
vented by eipoaure. The time occupied by the 
process varies with the intensity of the light. Soma 
likenesses were taken in five seconds, others occa* 
pied twenty, according as the sky was clear or 
clouded. The difficulty experienced, is to deter- 
mine the exact time that the plate should remala 
exposed to the vapor of mercury, the requisite time 
is at present determined only by trial, and the judg- 
raenl of the operator. It must therefore rcqmre 
some pmottee to produce the best pouiblc effects. 



k 



MAGAZINE OF SCIENCE. 



ISTUIBUTION OP ANIMAI-S. 

6dal view, vegrluldcA aevm inorr lihun* 

taiioalc: fo contrirjr. huwevtrr, in litis lo 

the tperios of animals, when compnirtl 

ofpUiiU, may be coruiJerc*) in the pnt- 

1. Hence it fcllovr* that botHiiy 

«lih xool'>g7.i5a(erY limited study : 

Miilered in relatiou to uiwct» alimc, 

on in the number of the tpecJefl. 

oas plants of Britain have beeaes- 

roond oainbers at 1500, while the iniectji 

t already been discovered in this country 

M^y many haftdredssUil remain unknown) 

10,000, which 13 oKM-e than jl\ insecta to 

. It ia therefore obt-bui that tlie know- 

Dired of tKe geo^caphicol diatribation of 

n comparison with what is known of plants, 

■and antahsfactorj : it ia likewise attcndrd 

(culties inseparable from the nature of beings 

roos and diversified, and which will always 

oftoiparatively imperfect. It rarely hap- 

a nagle specimen of a plant is found lao- 

; )>otanist can therefore immediately amve 

. ooarlusious : if he if in a mountainous 

he isenabled to trace, without much difti. 

lowe«t and the highest deration at which 

iUr sp«cira is found ; and the nature of the 

^ m^j be considered the food uf the plant. 

But these advantages do not 

ist 1 his business ia with nu/n^roa^ 

while of the marice tribes be 

hope to be [acquainted with toure than 

t ponioo. The following obicr- 

therefore, be copudered aa merely an 

general lavs which leem to regntote 

y of onimaU. 

tbution of animals on the face of the 

be considered under two heads, general 

sr. The first relates to families or 

babit&Bg particalar conei, and to others by 

ftre represented in onother hemisphere. 

d mfcra to the local distribution of the 

any particular country, or to that of in- 

*es. It is to the general distribution 

a celebrated writer has well obserred, 

xoologist should tint direct hitt 

than to the locality of species. By 

Motwre in her higher groups, we discover 

n fnacLiofM are dereloped upder different 

w« begin to discern something [of the 

of |>rovidence in the creation of animals, 

at generul rmults, which muMt ))c fnr eror 

Ihoae who limit ibelr views to the habita- 

Bpedea, or to the local distribution of 

lis, like plants, are generally found to be 
in tones. Fabricins, in speaking of in- 
tbe globe into eight climates, which 
the Indian, Ettyptinn, southern, 
northern, orientiil, occidental, nod 
firvt he includes the tropics ; in the 
region immrdiatrly adjacent ; 
i« lontbem ; in <he fourth, the coun- 
!ng on the Mediterranean Sea, iochiding 
i«nia and Media ; in the fifth, the northern 
when; the cold in winter is intense ; in 
North America, Japun, and China ; 
eighth, all tltose moanuins whoee Ham- 
covered with eternal snuw. It is, hotvet-er, 
:eiTe. that this, though a very ingenious, 
artificial theory ; the divioiona ire vague 



and arbitrary, and we know Umt animals nf one 
country differ essentially from tliote of another, 
although both may enjoy tlie same dcgrwr of tenijw- 
rature. M. LntreiUe has thrncfure ottnnpte^d a 
more definite theory. His two primary dtvistnns 
ore the arctic and Uie antarctic climatrs, acci>rding 
to their sitoation above or below the eqiiinortial 
line; and Uking 12^ of latitude for each climoie, 
he oubdividei) the whole into tweKe. Uc^inntng at 
84** N. L., he han seven arctic climates : vix, the 
poUr, subpolar, superior, intermediate, supmtropi- 
cal, tropical, equatorial : but his antarctic rlimates, 
OS no land has been discovered below 50° S. L., 
amount only to five, beginning with the equatorial, 
and terminating with the auperior. He propose!, 
also, a farther itivijnon of Butfcliroatea, by means of 
certain meridian line*; separating thoA lltu old 
world from the new, and subdividing the former 
into two great portions; an eastern, beginning with 
India; and a western, with Persia. He proposes, 
further, that each climate should be considered u 
having 24*^ of Inngitude and 12*^ of latitude. This 
system certainty approximates more to what we see 
in nature than that proposed by Fabriciiia; yet Mr. 
Kirby observes K-ith truth, that the divmlon of the 
globe into climates by equivalent parallels and me- 
ndiana wears the appearance of an artificial and 
arbitrary syotem, rather than of one according to 
nature. 

Mr. Swainson considers that the geographic dU- 
tribuliuu of animals is intimately connec-ted with the 
limits of those grand and obvious sections into 
which the globe is divided ; and that in proportion 
to the geagrarbii:al proximity of one continent to 
another, so will be either the proportional identity 
or the analogy of their respective animals. Hecoo* 
aiders Europe. Asia, and Africa «9 agreeing man 
particuUrlyJn possessingcertainanimalsinoommonf 
whir.haeem excluded altogether, from America and 
Aostralia ; both of which gre not only i»ulati'd iu 
situation, hut tbcir animals have it difference of 
form and habit from those of the three continents 
of the old world. He considers that the animal 
geography of Asia U connectecT with that of Aus- 
tralia by the intervention of Borneo, New Guinea, 
and the neigfabonring isles; while that of Amcrira 
unites irith Europe towards the polar regions. 
These five great types or divisions will, of course, 
present certain affinities or analogies dependent 
upon other causes, arising from temperature, food, 
and locality. 

Vertebrated animals have a wider range tban'.in- 
vertcbrated animals, thus resembling mim, who la 
spread over the whole earth : the dog and the crow 
ore found wild in almost every climate; the swal- 
low traverses, in a few dayn, from the tempernle to 
the torrid zone ; and numerous other birds annu- 
olly i»erform long migrations. Nestto-lbe!*e, inserts, 
above all| the other Invertehriitcc, enjoy ibe widest 
range; the house fly of America and of Euiojie aw 
precisely the same ; and Mr. Rwainsnn hns observed 
in Brazil vast flocks of butlerflic*, whirh annuiUy 
mignitfl from the interior townnU Hie coft*(. 

Marine animals have, in general, a wider range 
than those strictly terrestrial. This may probably 
originate in their being more independent ef the 
effects of temperature. It is remarkable, that, with 
the exception of the crow and two or three nthrrs. 
the land birds of America differ entirely from thoee 
of Europe, yet that nearly all our aquatiit speetott 
are found both in the new world and in the aoulhoni 
cOKita of Africa. 



MAGAZINE OF SCIE>JCE. 



p 



Subordioate to the tivr frcogni^Jtic groups already 
notieerl, trm^erature mi; be ciineiddred the phnci- 
pnl rfgulritor of the statioa of Miioials ; it ha5 like- 
wike rtrmtirkable influeuce oa their cintbing. Many 
quAtlrvprds, inh&faiting the colder region*, appetr in 
their natural culora during Eumtner, but become 
whitr ta winter. The same rhuige takes place in 
the pluruage of sereralland birds ; b'jtis not obier- 
vablc in inficcta, or the other invertebrate grotipa. 
Temperature has llki-wiac a Rreat influence on the 
aixe aiiil colur of antnialii. The Sphinx eotiv<SlTuli 
of Etiro|>e i« found also in India, but of ii much 
■oialler ci/e and more discinctiy colored : tbtit ia 
usually the effect of heat upon nntmaU whose chief 
t^ti^t ia in temperate Utitude5. On those which 
may be coniidered intertropical, a greater degree of 
heat not only increase* tht brilliancy of their colors, 
but adds to their aiie. There are many birda and 
inaecCa common l>oth to Central Brazil and Cayenne ; 
but from the greater beaC of the latter country, the 
specimens are always larger and llieirplnmagemore 
beautiful. Temperature likewise affects the clothing 
of animals in respect both to quality and quantity. 
Thia ia more, particularly observed in snch domesti- 
cated animals as have been tranaplanted from their 
natural climates. The covering of awine in warm 
countries coniiists of bristles of the same form and 
texture, thinly dispersed ; while the same animala 
in colder climates have an additional coating of fine 
frizzled wool next the skin, over which the long 
bristly hairs project. The difference is very re. 
markable in the swine of northern Europe and those 
of tropicjil America, the tatter appearing almost 
naked : it may be observed in a lees degree in those 
of the south of England nnd the north of Scotland. 
Similar appearances present themselves among the 
•beep of warm and cold countriea : the ticece of 
tboae of England consiate entirely of wool, while 
the sheep of Shetland and Iceland possess a fleece, 
rotiLniriing, tie^dCA the wool, a number of lon^ hairs, 
wliich give it an appearance of being very course. 
{To be eontinutd.) 

.,■■■■■■■. MJ..!**. . ^. .. .»--■■.■.■■■■.■.■.■■■■ — .■■ -■ — — .»■■. — ■ Ji.. - 

GILDING ON STEEL. 
Dif4sDi.vB any quantity of pi\d or platina in nitro- 
muriatic acid (a^tta rrgia), until un effervescence is 
oociuioned by the apptic^iiion of hrnt. Evuporote 
the solution of gold or platina, thus formed, to dry- 
nest, in a gentle heat ; (it will Uien be freed from 
alt cAccsfi of acid, which is eaieotial)j and re- 
ditaolve the dry mass in as little water oa poasible : 
next lukc nn instrument which ia used by chemists 
for dmpping liquids, known by tlie name of a sepa- 
rating-funnel, having a pear-shaped body, tapering 
to a fine point, and a neck capable of being stopped 
with the finger or a cork ; which may contain a 
liquid ounce, or more: fill it with the liquid about 
one quarter part; and the other three parts, must 
be filled with the *ery best sulphuric ether. If this 
be rightly managed, the two liquids will not mix. 
Then, place the tube in a huriiontal poaition, and 
gently tarn it round with the finger and thumb. 
Tha ether will very soon be impregnated with the 
platina or gold, which may be known by its change 
of color. Replace it in a perpendicular position, 
and let it rcit for twenty-four hours ; having first 
stopped the upper orifice with a small cork. The 
liquid wiU then be divided into two parta ; the 
dvlust colored being underneath. To sepnratc 
tbtm, uke oot the cork, and let the dark liquid 
flow ou( - when it h.if diaappMred, stop the lube 



immedintely with Clio cork ; and what remains 
the tubeia til fur use, and may be Called the g))dinc< 
liquid. Let it be put into a bottle, and tlghtl; 
corked. WTien an artirle is to be gilded, a ve»i 
of glass or unglased ware mu«t he provided, of jos 
sufficient size to admit the article : it most Uien h 
filled with the gilding-liquid, nearly t<i the top 
The steel roust be very highly polished, and be en 
tirely frre from rust or grease. A basin, full 
clean water, mu.'it be ready at hand : the ai 
must be immersed into the gilding -liquid, and tl 
lowed to remain as short a time lu pofutihle ; 
be taken out, quickly plunged into the watef* 
well rinsed ; it must nest he dnrd with blntd 
paper, and be placed in a temperature of IdO'^Fah^ 
till it be completeljr heated throughout ; it may t' 
be polished with rouge and a soft leather ; or, iridc 
is better, be burnished. 

!t will be aa well to obaerve. perhaps, that 
muriate of gold or platina, formed by digesting 
metals in nitro-muriatic acid, muat be entirely 
from all excess of acid ; because it will otb 
act too forcibly on the steel, and cause the coa 
ing of gold to peel off. Pure gold must lieemploy 
The other most not be shaken with the muriaiK 
gold, as ia advised in chemical puhlicationa ; for 
will be sure, then, to contain acid : but, if the t«0 
liquids be brought into contact, by the motion de« 
scribed* the affinity existing between ether and g 
is so strong, as to overcome the obstacle of graTity, 
and it will bold tlie gold in solution. The ethei 
solution may also bo conrrntrated by i;entle ev. 
ration. Care muat be taken not to wipe thft 
until the heat has been applied. Thia gilding 
effectual protection against rust ; and is, at 
same time, very ornamental. 



OBSERVATIONS ON THE FORMATION Of 
MISTS IN PARTICULAR SITUATIONS- 

or MIfL UUMPURbY DAVT. 

All persons who have been accustomed to the ob* 
8er\'ation uf nature, must have frequently Hitncsatd 
the formation of mista over the beds of rivers i 
lakes in calm and clear weather after aun-aet ; aod 
whoever haa considered thc»e phenomena in rrlatioa 
to the radiation and communication of heat i 
the nature of va|>or, since the publicatioo o( 
MM. Rumford, Leslie, Daltoo, and >A'eUa, cm 
hardly hare failed to discover the true cause ^, 
them. Ai, however, 1 am not aware that any wof^ 
has yet been published in which this cause is fulhr, 

>n>i<1icalcU 



discussed, aod as it involves rather co 
principles, 1 shall make no apology for • ^ 

few remarks on the aubject to the Royal > J 

As soon as the sun has disappeared fium a4| 
part of the globe, the lurfoce begins to lose bat 
by radiation, and in greater proportions as the alty 
is clearer ; but the Und and water are cooled by 
this operation in a very different manner : the iqi* 
presaion of cooling on the land is limited to Iht 
surface, and very slowly tranEmitted to tlie ioteriori 
whereas in water alfOTe \yf Fahrenheit, as sooe tm, 
tbe upper stratum is cooled, whether by radiatim 
or evaporation, it sinks in tbe mass of fluid, and 
its plut-f ia fuppbed by water from below, and liU 
ilic tenifKTOivire of the whole mass is reduc4.'d U>^ 
ncnrly 40'^ F., the Kurface cannot bo the coulott 
part. It follows, therefore, that wherever watar 
eatsta in considirrablc mat^a, and has a temperatHTB 
nearly equal to that of tlie lond, or only a few de» 
grcM below it, and above 40° F. at snn-tttt ita 



MAGAZINE OF SCIENCE. 



ihirii>S 1^^ night, In calm »ncl cte^sr wmttier, 

be vumcr than tKat of tUe coobeuooa land ; 

thm air *bovw Ibe Uiitt will iieccaaarilj bo colder 

ihnt aSi[iv« tbe wuLcr ; auil when Ifaej boih 

i'.ic pntjtnrtion v( aquroui vapor. 

I of the ^oiind u surh as to permit 

ii the laud to mix with the narmer 

>trr. mUt or fog will be the malt ; 

iter in qnnntity. aa the 

M,^ the wat^r is higher, 

.. ,v mperature of the water, 

1 h thr quantity or atrengtb of 

it, grc«t«'r. 

<^'b«erTations nhlch appear to 
•ko' rirtt at thii Tiew. June 9th, 

lAtureof the atmosphere and 
cjieatcdly exitniinvd during a 
.. i M..^-. .-I'JD thia river (rora lUti«bone 
«im3 on eocfa of these daj-t, the sky being 
dev, the «pi>fvrance of miat above the 
the rrcntnf noifonnly coincided with the 
of Ih*" ti»mperaturc of the air from three 
Mefi hit of iLe river, and the dis- 

h: luuraing vritb the elevation 
l»H.fr. t,;.^,, of the air a&opc that of the 
Fk9» lUtiabone to Paauu. the tempcratare 
Dorabe waa pretty fair throaehuui the 24 
Iwittg highest, 6r F.| or 62^' F.. between 
«fi^ two o'clock, and about one degree less 
the temperatiiro of the air from 
during thr- day, and from BV to 
laj tiif uight. R^Jow pM^Mn, the Ion and 
iBtotht Danube. The Dauubewaa gretniih. 
bad • milky blurnna, the llz was perfectly 
: but from the rapidity with which the Inn 
its wkteri at Uiij spot give their tint to 
• nrfsce. On examining the temperature 
/i««ra at ax o'clock, a.m. June 11, that of 
was found to be ti/* F., (hat of the 
v., *ud that of the lie 5fi^ P. : the tern- 
40 the atmoapbere ou the banks where 
II Mixed, was 54^ The whole surface 
ibc w*s csTvred with a thick fog ; on the 
r» sraa a slight miKf. and on the II2 barely a 
»t LiKticsiing the deptwition of a very small 
of water About 100 yards bcUiw the 
the three riven joined, the tcmperatare 
part of the Danube wu 59' P., and 
qasttdty of mist was less than on the bed 
before the janctioo ; but about half 
r, tbfl warmer water had again found its 
ffvf«oe, and the mist was as copious as 
'^lUon of the three rivers. June 12tb, 
cloody, and thft temperature of the 
lfr«natned till after dark higher than that 
brTng, whtn the lost obKrvation was 
K, when there was not the slightest ap- 
Ttie Bky was clearer before sun- 
fHA. And the tbermofoeter immediately 
• >r above the river, stood at 
r uf the Uanube beioK 61^F. ; 
1 inmtUiaiely above the river ; 
i5S of vapor to eiclado the 
rlUiippcared ; and was not 
-urface ; and in half an 
1 c was perfectly trans- 

slofif tlir Rhine from Cologne to Cob- 

'SlftS. ' InA and 3rd. the nights 

cfce^i; phenomenon of the 

- ,. ..served, precisely under 

t but u 1 could examine the 



temperature of the air and the river only ctote to 
the banks, sod in two or three situations, my ob* 
servations were less precise and less nuuurous : the 
mist formed later in the evening, and disappeared 
sooner in the morning than on Ibe Danube ; which 
was evidently owing to the circumstances of tbo . 
atmosphere being warmer, and the river colder. ^H 
temperature of the one being from 60° P. to Z^'^ l^f 
during the day, and that of the river, where ^T 
examined it, from 50° to 00'' F. 

July 11th. I examined the temperature of the 
Roab, ncAT Kermond, in Hungary, at seven o'clock 
p.m., and found it G5'' P., that of the atmosphero 
being 72^ F. During the whole evening there «V^| 
some thin fleecy clouds in the western sky, wh^H 
being lighted np by the setting sun, gre^y inter- 
fered with the cooling by rudiatioo from the earth, 
and at half.past nine, the Uiermometer, in the 
atmosphere, was still 69*^ F., and at half-past tea 
G7^ P., when there was not the slightest appearance 
of mist. In the morning, before sun-rise, the tcm* 
perature of the atmDBi>Uere on the banks was 61° P., 
that of the river 64 P., snd now the bed of the 
rirer wss Ailed with a white thin mist, which en- 
tirely disappeared half an hour after sun-rise. 

I made similar observations on the f^avc, in Car* 
niola, in the end of August: on the Isouso la the 
Friul, in the middle of September ; on the Po near 
F^mra, in the end of September ; and repeatedly 
on the Tiber, and on the small lakes in the Cam- 
pagna of Rome, in the beginning of October ; and 
I have never in any instance observed the formation 
of mist on a river or lake, when the temperature of 
the water has been lower than that of the atmosphere, 
even when the atmosphere was saturated with vapor. 

It might, at Unt view, be supposed, that whether 
the cooling cause existeil in the water or the land, 
the same conaeqaences ought to result ; but the 
peculiar properties of water, to which I referred in 
thr beginning of the paper, render this impossible. 
Water in abstmcting bent from the atmosphere be- 
comes lighter, and the warmer stratum rests on Ifaa 
stirfiue, and its operation in cooling the atmospheri 
is extremely slow ; besides, the cooled atmnsphei^^l 
stratum remains in contact with it, and water caiin^H 
be deposited from vapor, when that vapor is risiof 
into an atmosphere of a higher temperature than ita 
own ; and the law holds good however great the 
difference of temprrature. Thus. August 26th. at 
sun-set, the dny after a heavy fail of rain, and when 
the atmosphere was eiceetlingly moist, I ascertained 
the temperature of the Drove, near Spital, in Ca- 
rinthia, and though it was U'^ P. below that of tho 
air, yrt the atmosphere above the river waa perfectly 
transparent. 

It mny be imagined, but without any reference to 
the cooling sgencirs of the air from the land, mist 
may form upon rivers and lakea, merely from the 
toas of heat by radiation from the air, or the vapor 
itself immediately above the water ; and that the 
phenomena is merely one of the formation of 
va|>or, the source of heat being io the water, and 
its dcpositioD, the source of cold, being in the 
atmoaphere ; but it is extremely improbable that 
air or invisible vapor, at common temperatures, 
can lose any conndersble quantity of heat by radia- 
tion ; and if miat could be formed from laoh ft 
source, it must always be produced to a great extent 
upon the ocean in calm weather during Ibe night, 
particularty under the line and between the tropics, 
which the jonmnls of voyagea suftciently prove is 
not the case. 1 hare myself had on op poitunity of 



d 



of making tcmc olutervatioiu which coiadde with 
tbU view. During a voyage to and froai Pola, I 
passed the ui)thu of Sept., 3rcl, 5th, and Clb, off the 
coast of latna ; there was very little wind on either 
of the oights, and from sun-vet till nearly midoi^t 
it was |>erfeclly calm in alt of Uiem. On the 3rd 
It WSJ cloudy, and the lightaiog was perceived from 
a distant thunder-atorm, and the vessel was neve^ 
far from the shore ; but on the 5th and &lh the sky 
vra& perfectly clear, and the zodiacal light, after auu- 
•Bt, wondeKully distinct and brilliant, particularly 
on the ith, and we paased, by the help of oars, from 
two to eight milea firom the abore. The tcnipera- 
Core of the sea at sua-iet was 76^ F. on the bth^ 
77*^ F- on the 6ih. that of the atmosphere imme- 
diately above it 78" F. and 79^ F. On the &th at 
midnight, about five miles from the shore, the (cm* 
persture of tlie sea was 74° F., and that of the 
Atmosphere 75° F. There was not the slightest 
appearance of mist od either of these nights on the 
open sea, or at any distance from the land ; but 
cioae under the hills of htria there was a slight line 
of haie rinible before can-rise, which was thickest 
under the highest land ; and ajs we approached, at 
ftun>rifte on the 7th, (lie mountains of the Kriul, the 
tops of those nearest to Trieste were seen rising out 
of a thick white mist, wluch had not reached a 
quarter of a mile from the stiore. 

After mists have formed above rivers and lakes, 
their increaae seems not only to depend npon the 
constant operation of the cause which originally 
produced them, but Likewise upon the radiation of 
beat from the aopcrficial particles of water com- 
posing the mist, which produces a desceudlog cur* 
not of cold air in the very body of the mist, whilst 
the warm air oontinually sends op vapors : it is to 
these circumstanoea that the phenomena must be 
ascribed of mista from a river or lake, sometimes 
arising considerably above the surruunding hills. 
I have often witncsKd this appearance during the 
month of October, after very stilt and very clear 
nights, in the Campagna of Kome above the Tiber, 
and 00 Monte Albano over the lakes eiistiog in the 
ancient craters of this extinguished volcano, and, in 
one instance*, on the 17th of October, before sun- 
rise, there out being a breath of wind, a dense white 
doad of a pyramidal form was seer, on the site of the 
Alban lake, and rising far above the highest peak of 
the mountain, its form gradually cJianged after sun- 
liM, its apcLi first disappeared, and its body, as it 
were, melted away in the sun-beams. 

Where riven rise from great sources in the inte* 
rior of rocks or strata, as they have the mean tem- 
perature of the climate, mists can rarely form npon 
them, except in winter, or late in autumn, or early 
in spring. In pavstng across the Apenniues, on 
October lit, 2nd, and 3rd, 181S, there having been 
much rain for some days preceding, and the nights 
being very clear, I observed the beds of all ttlf^ rivers 
in the valleys filled with mist, morning and evening, 
except that of the Clitumiuii near its source, in 
which there was nu mist, and this river rises at once 
from a limestone bed, and when I examined it, at 
half-past six o'clock, a.m., October 3, was 7}^ lower 
than the atmosphere. 

Great dryness in the air, or a current of dry air 
passing across a river, will prevent the formation of 
miat, even when the temperature of tlie water is 
much higher than that of the atmosphere ; thus, on 
the I4th of June, near Mautern, though the Danube 
at five iu the morning was Gl"^ F., and the air only 
^i'", yet there was oo mist; bat a strong cislerly 



wind blew, and from the rapidity with which watte 
evaporated, it was evident that Utis wind wu ta 4 
stale of eztrrme dryneas. 

The Tiber baa furnished me with a number of 
still more striking examples. October lOth, tU 
night having been very clear, on arrivine nt tht 
Ponte Mello, at half-past six la the m 
found 00 mist on the river, yet the tcnij" 
the air immediately above it was 48^ F., aa^ :.»■. ». 
the river ^6' F. i a strong north wind blew, whidi 
indicated, hy the hygrometer, a degree of dryaess 
of 56% and thij part of the river was exposed to H ; 
but the valley above, where the river was »hcltcn4 
from the wind, waa full of mist, and the mist la 
rising to the exposed level might be seen, as it weit^ 
dissolving, presenting thin striK whi<^ never reach«4 
above s certain elevatioD. and many of which diMkp- 
peared a few seconds after they rose. From the 
I3th to the 25th of October* during which time the 
tj-araontanc or north wind blew, 1 witnessed repeat* 
edly the same phenomena, and in the whole of thii 
time there was only one morning when there was no 
mist in the sheltered valley, and tlie cause was per* 
fectly obvious ; the night had been very cloudy, bs4 
tite thermometer, before snn-rise, indicated a diff^ 
nnoe of only one degree in the atmoBphere bsiov 
that of the river. 

It ia not my intention to discuss the general sul^ 
ject of the deposition of water ft'om the atmoaphcfv 
in thia paper ; hut merely to describe a locjil dUM 
of considerable extent and variety in its modificia 
tions, and which is not without an effect in (hs 
economy of nature -, for verdure and fertility, in hflC 
climates, generally follow the courses of rivera, aaA 
by the operation of this cause, are extended to the 
hills, and even 10 the plains surrounding Lhllr 
banks. — PhitoMophical TVonsacfi^mt. . 



ON SEASONING TIMBER. 

Tub premature decay of timber, and especially qf 
the oak. by what ia technically called the dry ro(, 
is a subject which has occupied no small share flt 
public attention. If we may credit all that we v% 
and hear, the immerRing of limber in Kyan''s m< 
curial preparation is the nearest approximation to 
the long wished-for desideratum. Still I cam 
conceal my doubts as to its general utility. Ill 
application to timber for lighter purposes may b« qf 
much use in promoting durability ; but ita octiim 
on the huge timbers of eren a third-rate man o( 
war will, \ fear, come inliottely abort of etpccta* 
tion ; and, indeed, I think it highly probsbU; tlul 
aftcr-rxpcrii'nce will prove that, from the cUima af 
a decided specific, Kyan's process must degenorsM 
to the rank of an expensive auxiliary. 

In all our attempts to arrest the progress of diy 
rot, there seems to bean obvious misdirection of tl^ 
quiry ; our investigations not having been yet directeJ 
to the more immediate cause of the maUdy. to 
organic bodies preventives are always prefembtc tQ 
cures; therefore, wherever detrimental effects pre* 
sent themselves, we uught at once to turn our sttfa< 
tion to the producing cause with a view tii its re- 
moval, rather than to the application of tem]>orary 
palliatives. That the appearance of precocionH de- 
cay in manufactured timber may be tmr- 
presence of nlburnaus matter, in iu Hii 
the aap vesaels, is a fuct generally admttt* 1 .. .tim 
an oak tree with its Vfgctatire powers in full opcrm^ 
tion is felled, the sap, or albumous fluid, nut havinc 
hecD perfin:ted, or converted by the process of fotiit- 



rfAXSAZINE OF SCIENCE. 



atjoD to' iti ultiiTute purpose, beoomes 
in ipeedily commrace*. and in 

binmunicatea witb, and conts- 
.^.,d*.t parts of tbe fibrous column, 
ins employed by nature in decom- 
_ ie matter do«a not appear to have 
doe ■hare of consideratton from the 
The agency of albamoan matter in ao 
ttate U allowed ; but, judging from the 

t subaisld between animal and vegetable 
re can only riew this an a secondary cause. 

ica, whether animal or vegftnble, whern 

OMuud to exist, it seems to be a universal 
an*, in the process of derompoiiilion, to 
e active foreign power. Self-deotructioD 
MftMe in the natural code; therefore we 
kSaored that there is aomething ebie in 

than merely tlie presence of ijmple albur- 
Animal bodies contain the seeds of 

within themaeWn ; the different fluids 

conntlr.u millions of animated beings. 

rital functions are brought to a close, 

tenants of the veins and arteriei com. 

I work of derafltation upon the more 
matter : the putrid mass eogenderi ani- 
rger dimensions, to gnaw the sounder por- 
}fnsme, and, shortly afterwards, the loath- 

of uniting farth to earth is accomplished, 
aible that the decomposition of vegetable 

is performed by meaDs not rery dissimi- 
it of animals. The germs of the dry rot 
nmnnicated to the fibrous mnn through 
xn of the secretive organs at the root. 
I Cfaealbamoas fluid is tenanted by legions 
Cttlet, the patrid recoains of which iirthe 
t may form a soil, or bed, for the deTe> 

of tJie embryo fungus. Immersion in 
Vublimate impsrts no additional strength 
ody Abre. it only destroys the ritality of 

in which the dry rot originates ; anff, if 
Kng remarks on the origin of the malady 

io truth, then we have within uar reach 
IaUj, or even more, effectife, and far Itfju 
, than corrosive lubUmate. If it can be 

ved, that unconverted sap in timber b 

of the dry rot, as already suggested, then 
needed recently ia the inventing of a pro^ 

'by the sap cau be completely extracted 
of almoit any size. By this process (the 

r the prrpanng of which onn be hnd for 

anywhere) 1 find that oak timber can be 
the up, and so seasoned, tliat, in less 
nnn aft^r being cut, it may be put into 

of the carpenter. It was my intention 
lui process to preventing the shrinking 
log of larch timber ; but I have not had 

oity as yet of matting the espcriuicot: 

X have Hcn of tta efleota on oak, bow- 

bertaiu the most sanguine hopes of aaccess. 

ttude to act on superficial evidence is a 

on to our nature ; and hence we are too 
Io mistake effert for cauRe. Preemptions 
dry rot, is an efTect, in my opinion, pro- 
most ^Instaaces by tlw very ({uvstiunablo 
> which oak tiuihtr is harvested. In 
It of the other epecies of hard-wood treei, 
variable practice to have them cut down 
nation is in its most inert state ; but, from 

aluo of its hark, the oak furuis an excep- 

most judicious rule. The process of 

only be performed when vegetation 

ty, and certainly it requires no argii< 




nent to show dut this, of all seaions la the year, 
is the most improper to frll timber of any sort, if 
durability is Co be taken into consideration. Oak 
bark foruis no contemptible item of our rnlnnd com- 
merce ; and to propose that alt oak-trees to be ap- 
plied to marine constructionft should- be cut down 
in the months of December and January, will be a 
startling announcement to some economical pro- 
prietor!) and stewards, as by such a course the value 
of the bark must be sacrificed ; but I propOK no 
such thing to them. Let it be remembered that I 
am writing with a view solely to the stability of the 
wooden wsUs of old England. I am not patriot 
enough to recommend individual sacrifice for the 
poblic good, wfaea there exists no necessity for tt. 
This is the nge for," compensation ;" and when, 
collectively, we cam afford to present the West India 
planters with twenty miltiotis sterling for performing 
one single act of jaoticc, snn^ly, when treating with 
oak-venders to furnish our timber depdts with 9onnd 
material, we can well afford to make an equitable 
allowance (or the bark, if it can be proved, as I 
think it easily may, that we would be gainers thereby. 

All timber, then, for the oae of the British navy, 
OQgfat to be purchased growing, with an under- 
standing between the contracting parties, that the 
vendor alialt be bound to fell the trees at such sea- 
sons OS may be agreed upon ; namely, in the months 
of December or January. Had some such plan aa 
this been adopted long ago by the officers of the 
public dockyards, It is my firm belief that dry rot 
would have been much less prevalent. Even the 
process of felling herein recom mended is susceptible 
uf Improvement. Where any large oaktree fit for 
naral purposes is sold, It might be Mmiiged that 
the purchaser should be allowed two, three, of 
more, years to remove it. In this interim, vegeta- 
tion might be gradually retarded, by severing from 
the main root, annually, so many of the principal 
lateral roots, until the foliage aU but refused to 
expand. Under this treatment the usual copioas 
flow of sap would be diminished ; and, by redudng 
the mediiiin of its a.<!icrnt annually, the libre would 
become seasoned, and would acqnire a rigidity and 
toughness not obtainable under the old regimen. 

CiuUe jsAb^. J. ucvno, 

PETRIFIED HUMAN BONES. 
Dr. Lund, now residing at Xjigoa Santa, In Brijil, 
states that upon a lote journey into the interior of 
firaxil, he had, for the first time, met with bumoa 
hones, in conjunction with the hones of acknow- 
ledged extinct animals, which must be of au ex- 
traordinary antiquity, perhaps the oldest human 
bones that have ever been found ; for they arc in 
part petrified, and in their preservi'd condition alto- 
gether corrpflpond with those of the extinct auimala, 
in connciioD with whicb they were found. They 
will, he observes, throw a light on the nature of 
the inhabitants of this part of South America, in 
times which go much farther back than our know, 
ledge of this part of the world. The formitloD of 
the cranium is extraordinary, ina-smuch as the fore- 
head does not rise in the same plnne with the face, 
but forms a considerable angle, by which pecalinHty 
they differ from all craniums of living races of meti, 
and resemble the depressed heads represented in 
the ancient drawings of the Mexicans. In con- 
nexion with the extraordinary hones, was found a 
hemispherical-shaped stone, quite polished un the 
under sarfucc, which had evidently betn used for 
rubbing. 



A 



J 



MAGAZINE Ol 



MEDICAL RECEIPTS. 

FOn TlIK TRKTII. 
Hudton'* Pmertatit>e consisU of eqiul parti of | 
the tintiture of birk, rojrrh, wid cmninioD, with • 
Utile f!um ftrtibio. , 

Hfwtie't ia mide by roUiinc 4 graioi of ehlori- 
nateil Umc ichloriJe of lime) with 2 drams of pow- 
der«l gum or red coral ; this is recommeDdcd as a 
sweetener of the brcsth, and to t^ke off yellowDCH 
from tlie tceth. 

Grfenovgh't Tmcturt. — Tnke 2 onnc« of bitter 
dmoiids. half «n ounce each of Draxil wood and 
cassia berries, 2 dramft of Florentioe orris root, 1 
dnm each of bmoialate of potass, &lam and cochi> 
neal, half an ounce of spirit of horse-rmdiah, and 2 
pints of spirits of wine. 

Green't Thoth^povrder.—Ttkt 1 onnce each of 
dried sage leaves, crust of bread, and chloride of 
lodiom. and 1 dram each of nutmeg and cIotcs 
powdered ; triturate and mix in a morUr, 

RuMiiai'M Tincture fvr (At 7>WA.— Take 8 ounces 
of Florentine iria root and rhaUny root, 1 ounce of 
cloves, 1 scruple of amber^Kriae, 2 grains of musk, 
2 pints of spirits of wine; make a tincture and 
apply it with a bit of sponge or ootlon. It ia not 
10 good as tincture of mjrrh. 

Dele*cotV$ Myrtle Opio/f.— Simmer 21ba. of 
honey with half a pint of rose-water in an eartheo 
Teasel over a alow ftre. for a few minutes, and then 
mix it with a tooth-powder prepared from myrrh 
utd Armenian bolr, into a soft paste. It is laid on 
with a brush and ia good for sweeteoing the t«rcath. 
Parisian Dentrifict. — Take 4 ounces each of pow- 
dered FloiWSoe iris and TeruTisu bark, 12 ouocea 
of prepared chalk, (whiting,) I ounce of myrrh, 1 
ounce and a half of roBc-pink.and IG drops each of 
the oils of cloves and of cinnamon. 

Barktr'a I'ootk 2Tintf/wre.— Take any quantity of 
alcoholic infusion of pyrethrum, (feverfew) and 
color witli tincture of red cabbage. 

Laennic's Remedy for r&oM-fleAe.— Mix 1 dram 
of creosote and 13 drams of spirits of wine ; to be 
applied on cotton wool. 

Mineral Metallic Cemtnt.—Ku amalgam of tin 
foil and quickiiiWeT, combined with iron filings, 
finely levigated for filling decayed teeth. 

Z,e Dray't Marmoretum. — An amalgam of tia 
foil with quicksilver, combined wilb some Tery finely 
powdered fitnt glus. 

Mallan'x Sncctdaneum ia nearly the aame aa 
Ihe tin-foil on the back of looking glasses. It may 
be made by rubbing together quiokaiWer and tin- 
foil in a mortar, or melting them together in aludle 
OTcr a iire, and applying them wbile warm. It 
grows harder by degrees as the quicksilver becomes 
•baorbed. 

Lardner'a Prepared r*arcoaf.— Chalk, colored 
grey with charcoal. 

Grorpenor'9 Tooth-powder. — Kose<pink Slbs., 
palvcnzed orris root ^Ib., oyster shells 31bfl., oil of 
rhodium 25 drops. 

Atiatic l}e»ti/rice. — Powdered red coral 6 ounces, 
Vrnctian red 6 drnms, red ocliro and pumice stone 
each 1 ounce, mu*k i dram. 

Hemet'9 Dentifrice. — CutUc fish bone fib., cream 
of tartar \\\3, orrts root 2 ouneca. 

Green Tooth-povder. — Dry asge leaves, toasted 
crust of bread, and common salt each 1 ounce, nut- 
mrg and clove* each 1 dram. 



I>£PlLATOni»»; 
OK, coarsMtTion to t*M on terKavtvucl ««l» 

Take of quicklime lib., orpirocnt ^rama, 
root 2 drams, saltpetre 1 dram, sdipw ^ljj 
aoap-lees half a pint ; evaporate to a pff^ 

sistence. 

Roseate Potcrfer.— Lime ]2 ounces, starO 
ouncefl, orpimcnl 1 ounce; mi« thtm ti>grthar, 
Boyle' M Depilatory. — Take equal parts ofool 
and quicklime, powder them separately and cfll 
them ia water tilt they form a thick paste. T 
laid over the part whence the hairs ;are to Ij 
moved, and afterwards wiped off with a wet d 
Strong Dejrilatory. — Take 1 ounce of g« 
and 1 dram each of orpiment, ant's eggs, Ul 
arable reduce to powder and make Into pastti 
vinegar. 

Turkieh Drpilatory. —Tmkt 5 onncca of i 
lime and 1 ounce of orpiment, reduce th*am 
ralely to fine powder, mia well and fift. 
strong add l-aeventh or 1 -eighth of starch pa 
form into a poiite with warm water, and ap 
before. 

Deleeroix't Depilatory, or Poudre SHbtiU 
Colley'M Depilatory, composed like the r 
quicklime and seaqni-snlphuret of arsenic (orp^ 
perfumed with orris root powder and ten 
with atarcb. 

[It is to be remarked that tbo use of all de 
riea ia attended with danger, aa it Is by the a 
tion of the very poisonous snlphurcl of areaol 
ihey produce the effect eipected from 



tbuu 



lIAin DYES. aie. 

Enenee <\f Tyre \m merely a solatioaj 
of silver, (lunar caustic.) 

Grecian Water, or Hajna»*t Djfe, 
of nitrate of ailver, colored with syrup of 
diom. 

Orjila'M Hair /)y«.— Plurobile of limf, w 
boiling for an hour and a quarter 4 parts oT 
of lead, with i parts of Klskod lime, ai 
of water, filtering the liquor, and 
powder. This, in a warm solotion, 
hair a fine black in one hour. 

f Ve'« Dye. — Dr. Ure recommends a 
by mixing litharge, sUked lime, aud bit 
potass, (pearl-ash) in various proporlit 
to the shade of color desired ; he all 
the salts of mercury, lead, bismuth, as mtM \ 
oxydes, blacken hair, by the formation, hk 
bably. of metallic sulphurcls. ^ 

Foi'» Cream for the Hair— Pot into 
ounces each of marrow pomatum and alrai 
melt gently by the fire, and while cooHng 
2 drams of oil of jessamine or bergamot. 

Rjou'landu Bstenrf of Tyre is also a A 
solution of nitrate of silver. 

Rovtand's .Ifaecusar Oil is made by 
any rancid oil with onions or garlic, to taki 
bad smell, and Bcenting with oil of roi 
coloring while warm with olkanet root. 

Note. — We intend to give each month a c 
oflittle-knoft-n and vjloablo receipts, si 
above. 



liiiju 



VoU. 1 and 2 (j/" ihi» Magazine art now rt^ 

ffontly bound in Cloth and Lettered, prie* 



l^vnnx rriDlMl by O. rii*ll«ia. C. Whit* H..r»» t*nt. M-U VIikI.— PublUbvd by W. n«ttiAiH. II. 1 -Icti 

C^titmiitiUsiioin, fwliJch ir* aaswaiwJ on ihe Wran*" "' ""■ Pa»U) u-lie sddrtmd to UieWiiw.alw.GraaU 




H\T)RAULIC ENGINES- 



csoiutldcird in a Conner paper tboic hy- 
pMm which ftct by the pressure uf the 
■noolf culled pumps, it ia ailvijablf* 
mttetttion to the most remarkahle of 
br mechanical meani only. 
ouc of the mcMt ancient, as well as one 
effcctire, was the tympatium. 
of 1 great hollow wltccl, composed of 
joined together, and well calked and 
Ltng, as itc name iniportu, a kind of 
dnxm, aad haTing a hurizoiital uXe on 
turru. The interior ia divided by eight 
into u many equal fpaoea or cells, each of 
an oriAce of about half a foot in the rim 
or wheel, shaped so as to facilitate the 
the water : there are, moreover, eight 
iiMiU running Contignoas to each other 
L — NO. U. 



and pondli'l to die aile of the wheel, ench corrrs- 
ponding to one of the eight large cells, throii^U 
which the water pasiCfl from the cells just mentioned, 
and after running along the channels to a convenient 
distance, escapes through orifices into a reservoir 
placed just beneath the axle of the wheel. Thus 
the wster is elevated t)irough a vertical space equal 
to the radios of the hollow wheel. When the tym- 
panum is used to raise water from a running stream, 
it is moved by means of float-boards impelled by 
the stream; but when employed to raise stagnant 
water, it receives motion from a foot-wheel placed 
on the same shaft, turned by men walking inside. 
Tlie chief defect of thi« machine is, lh:it it raises the 
water in the most disadranltigcou't jjitualion possible: 
for the load being found always towards the extremity 
of a radius of the wheels the arm of the cfl'ectiys 



^ 



10 



MAGAZINE OF SCIENCE. 



lorer which answcri to it, mn-cMcs through tUc 
wluAe ijufulniat Uie wftter dencribcK in [i.i.<!iing from 
the bottom of th(* wheel Co the altitude of it< ci ntrt- ; 
«(i that the power tduhI art in like manner u if it 
wprt" npplird at a winch -hanflle, and conAcquentlj. 
connot act unifannly. 

M. di" In Fnyc, to rrmrdy this defect, iIpv'hum) a 
machine which may here ht^ dftifrihed, logetho' with 
the prooTM of rvaNmui^j tliat led tn it. 

W'hrn we dpvcloj»r the circiunfermcc of a ctn-lr, 
a curvti is described (i. e., the involute) of which all 
tb« radii arc ao many Ungcnta to the circle, and are 
Ukeviee all respectively perpendicular to the several 
points of the cur%'e described, which hna for it* 
greatest radius a line equal to the (>eriphcry of the 
circle evolved. Tlie truth of whitii i» shown by 
geomi-tririans when treating of the genefiia nf evolittr 
asd involute cnrvea. 

Hence, hai-ing an lule whose cirnmifierpnoe o Uttlo 
nceetU the height which the water is propodcd to be 
elevated, let the circmnferenceof thonilebc eTolved, 
and make a cnrred canal who^e cunature shall <;'jjn. 
cide tlirouKhout exactly with that of the involute 
just fornied : if the. fiirther extremity of this canal 
be made to enter the water that is to be elevated, 
and the other extremity abut upon the Bhaft wliich 
if tamed, then, in the course of the rotAtiou, the 
water will rise in a vertical direction, tang:entia] to 
the shaft, and perpendicular to the canal in whatever 
poaitinn it may be. Tliua the action of the weight 
annwerihfj nlways to the eitrctnity of a horixontal 
radiufi, will be as though4t acted ui>on the invariable 
arm of a lever, and the power which nuaes tlie 
weight will be always the aame : and if die radius 
of the wheel, of which tliis hoUow canal ■erves as a 
bent apoke, is equal to the height that the water is 
to be raised, and conscqnently equal to the cir- 
cnmference of the axle or shaft, the power will be 
to the load of water reciprocally as the radius of a 
circle to itfcirciunfcreuce, or directly as \io 6i nearly. 
In M. de la Faye's opinion, the machine ought 
to be eompoeed of four of these canaU ; but it has 
often been conetrucicd with eight, aM represented in 
our flgurc. The wheel being turned by the impul- 
sion of the streiun ujHin the Hoat-boardii, the oriAccit 
1* L, Ac. of tlie carrilinejir canaln, dip one 
after another into the water which runs into them ; 
and as the wheel revolves, the fluid risea in the 
ctinula, C, C, C, C, &C., and runs out in a stream M 
from the holes at N ; it is received into the troogfa, 
and conveyed from thence by pipes, 

By this construction the weight to be raised offers 
always the same reaistanoe, and that the least 
possible, while the power iii applied in the most ad- 
vantageooa manner the circumstances will admit of. 
Ai in many eaaea water is to be raised higher tlian 
the radius of any wheel that can well be made, we 
shall dcHcrihe a machine called the Perttan tehee!, 
which, like the machine of M. de Faye, may be 
turned by means of a slreain of water acting upon 
the float boards of the wheel. It. had, however, 
tile disadvantage attending the tympanum, which 
ii, that it can only raise water to the height of its 
semi •diameter. 

Tlie buckets B C D E, dec. are Aunff upon the 
wheel by stroDg pins, Axed In the side of the rim ; 
which must be made as liigh as tlie water i» intended 
to be raised above the level of that part of the 
stream in which the wheel i* placi^d. As the wheel 
turns, the tuckets on the left hand go down into 
tiie water, where they are filled, and return up full 
on the right hand, till they come to the top at P ; 



wherr they strike ngninSt Uic end of tl*r fta4| 

tmugh O, bv wliich they art oven'-' * - --— '- 

the water into the trough ; from ■>• 

conveyed in pipes to any plan; it ' 

and as each bucket gett over tJie trough, it lalli uito 

a prrpcndicular position again, and so c-s ^nwn 

empty till it comes to the ^atrr at A 

Ailed as before. On each bucket if a s\n 

^ing over the top or cnjwn of tlie troujgii ^ 

the hotloni of the bucket above the IcvlO of its 

and so causcs it to emjity all its water into the I 

DISTRIBUTION OF ANIMALS. 
fRtrtimed from pagt 4, and twichideJij 

The particular or local distribution of antmali 
is affected by various causes whirh have little tn(1o> 
enoe on their geographic distnbutinu. I'hus tba 
jiurely insectivnroQS bird* nf the fairily sylrladK 
feed on all small kinds of ic<iects, without regard tv 
any particular species ; yet the sylriadte nf Ameriet 
and Those of Europe are each characterized by a 
pcculinrity of structure which invnriAbly designattt 
the continent to which they belong. The wrTnnft 
is represented in America by the oxyrhynchua 
tatns ; yet neither of these turd» if found to inhabit 
all parts of their respective continents : their rvogi^ 
on tlic contrary, is reguUtrtl by tetiiperature. food|. 
and other drcamstances connected with local dUr 
trilmtion. 

Prom temiierature originate all the caoses «l 
aJTect local distrihutioo, namely, food, situatUm. vA 
migration. Were the climate of this country «a 
nnchanging as that of Brazil, the insects which no* 
have only a single brood in the year might then pnv 
dace several, and the swallow woold no longer b« 
obliged to quit us as now, for food in oUier cUoifttja, 
at soon as our insect season was at an end. lMigr»< 
tion and torpidity arc eijually the effect of temper*' 
ture ; the tirtt depends npon the effect whkk If 
changes of the seasons produce in the abondaooei 
scarcity of food, whether animal or vegetabLc i thi 
Istter is a state of inaction during which the ncce^ 
sity for daily nourishment is suspended. 

The migration of birds and of fish is more cJctuo* 
sive than that of quadrupeds. The birds ol thi 
Polar regions migrate to Britain daring 
winters ; while those of .^.frica come to ■». in 
season when the southern beats are most intenvi 
but tha same species which is migratory in oo* 
country is in some cases slationary in another. U 
is stated that the linnet is migratory in Greenla&ili 
but that it is stationary in Britain. 

The torpidity or hybernation of animals is 
dently designed to suspend the necessity of laktof 
food during the winter ; althongh in some coses 
small stock of provisions is laid up,' most probaMf 
to serve for nourishment previously to entire to«^ 
pidity taking place. Several quadrupeds are snb* 
jcct to this partial luspenaion of life, as the dflP- 
mouse, hedgehog, bat, marmot, &c. It is said tbfll 
birds have sometimes been found in a simihr ttatsj 
but this is very questionable. Among insects, on 
the contrary, torpidity is very common, and a lar|S 
proportion, when undergoing transformation, piM 
a considerable part of their lives in this state. 
Situation hss an extensive influence on the 
distribution of animals, although it has little 
geographical diatribntlon of groups. Air, t\ 
and water, have their di»tinet iohnbitanU, vliich sre 
again restricted to certain situations in their 
spceCive elements. The higher regions of tbi itf^j 





HYDRAULIC ENGINES, 



lira eobaUervd hi a former paper those hy. 

""^ whtt:h set by the jircuure of the 

:iimnnljr caltpii pn[u|H, it is ulrisable 

' Atientlon to the most remorluble of 

iK't by uiecluuiical meuu only. 

one of the most andent, u well u ooe 

Tctive, wu the tympanvm. 

t great hollow wheel, comfKiaed of 
I'ined together, and well calked and 
:;;, afl its name iinportn, n kind of 
,,, and boring a horiKOUtal axle on 
torn*. The interior is divided bj eight 
Into as many equal spaces or cells, each of 
an oriflce of about half a foot in the rim 
or wheel, shaped m as to facilitate the 
erf the water : there arc, moreover, eight 
channels mnninj; eootiguoas to each Qtber 
lU. — NO. U. 



!CntBi 



and pArntlel to Eho axle of the wheel, enrh corres- 
ponding to one of the eight \arge cells, throiittb 
which the water passes from the ct-lls just mentioned, 
and after running along the channels to a convenient 
dUtanee, escajtes through orifices into a resorvoir 
placed jost beneath the axle of the wheel. Thus 
the water is elevated through a vertical space equal 
to the radius of the hollow wheel. When the tym- 
panum \s used to raise water from a running stream* 
it is moved by means of float-boards ioipolled by 
the stream ; but when employed to raise stagnant 
water* it re(x:ivea motion frum a foot- wheel placed 
on the same shaft, turned by men wulkin|^ inside, 
'llic chief defect of this machine is. tlut U raises tha 
watfT in the most disadvantngcoatt situntion t»o»sible: 
for the load being found alwaya towards the eztrrmity 
of a radius of ibc wbeelf tbc arm uf the effective 



Bbnk 



12 



MACAZISE OF SCIENCE. 



gmbfyo or Jtvmi*/ u visible — ibU cousItU 'of two 
ioAt$ or eotyiedoim, attached to eiich otbrr by t 
bmrt-iihaped buiiv, calleH the corcftlnm — the lowitr 
endnfwbirb, thti raHide, products the fature root, 
nod tb« upper rnd ox plumule the future atem, while 
the lobes jive the fir^t nounsbmeot to the jouni; 
plane. 

rttf. 1 Sulevlcwof ■ licMi. a EfUlvienofdlltP. X Th* 
umer'.rw.ihr cent ontw mhU bvLngrvmund. 4 Thf> Min« 
ufHrnctf, tltuwiiig 111* imo lobr*. the laillrlv (A.f um) tbr rila- 
mul* itlj 

In ffome leeds, betides the embryo, there i> ■ 
poftiuQ which when young is fluid or pulpy, and is 
iotendrd to nourish tbe seedling plant, in the lame 
manner as the white of an egg nourishu the young 
chicken, and which it therefore csUrd albumen. 
Sometimes the albumen in wholly sbiorbed during 
ike ri}N3nlng of the (teed ; in other cases it is found 
aftarivards as a nut-like, homy or mealy Gubstance, 
ll>u« nimott the whole of a grain of wheat is albu- 
men— lo is tbe hard ttone of the dale, and Che deah 
ofthe cocoB nut. In the last ioilancc part of tbe 
albutttrn remaioa flnid. which we know as the mitk 
of the fruit. A thin akin, called the membrane, la 
alto found Bometimes witbtii the tnta, as in the 
wslnut t and in many inAtauccs an extra coat onre- 
lopea it — this ia called the nrii. The bean sboro 
rtprescntcd has neither albumen nor aril. TTio 
nntmr^ flctrd baj both: the inaoe lathe one, and 
the mund aromatic part, commonly known as the 
xiutcnet;, U the otJicr — the embryo being exceedingly 
small. 

t)f the Tarioua parta of a seed the embryo is the 
jnoft ef4enti«l. as it is this which grows into the 
fulnre plant, and without which no seed is perfect, 
Iffiwcvnr well formed it may appear. The embryo 
i* sonii'tirnes erect (1) as in the dandelion and other 
componnd flowers j rereraed or hsngiii; by the 
upper (ud (2) as in parsley, and the rest of its order; 
wr boiiiftnliil (3) as in the prlmrote. Itjt particular 
atisfke varies materially: it maybe Htraight(l) — 
coiled up (j)'-apinil (6) — annular (7)— or bowed, 
b«nit, and plaited in Tarlooa ways. 




I. Kmfifjo rr Dondrllia 5. Ditto of Pnnlfy X I»U!ci 
of th* t'r.mro**. 4 I>Lilo nt lh« Anim. i. tU'.to of llici 
lta\\ a tittbi iiF Ihfl IKhIiIct. 7. Hlllo nf llio t.ycbuU. 
the S)itu»eh, and very mniiy other |;rt>cnt d planli. 

8uch sfrnU as agree with tbe above description in 
having two cutyledona opposite to each other ; also 
those few plunts which have more than two are 
called dico/y/ef/onDUf; but tliere are others which 
are never found willi morccotyli-dons than one, (or 
if thne are innre they are not opposite to each 
otb«ri) sacb, for example, as the grasses and the 
lilifi. T' '•'■■ -''..u arc called monorofi/hdonotift, 
while tl. I lantfi, having no cotyledon at 

all, are * fJonouM. It is in botany of the 

6rst necc»»ity to puy uttantjon to these three words, 
because the plants of the. one or other kind hava 
such Ytry uifftrcut cbar/tctcrs of leaves, stems, and 
general atruiiure, thnt the foaodatiun of the whole 
arrangflment of pbuta in natural ordcre drpvudt 
upon thcie differettcri. 



!n the color of secda almost every tint may li» 
found. Various shades of brown, red, and str«« 
culjr, are ronimon— black and white scarcely fcis 
BO. Brilliant yellowa, blues, purplra, and gteeita, 
are more nire ; but bright acarleta, crittiaf>«ts, and 
delicate flesh colors occur fi^qnently, whilo baay 
arc most beautifully mottled and speckled — an u- 
stani'c of which we see la tbe different vanciios of 
Llie French bcdn. 

The sh.i]te of seeda ia nu leM varied. Tbry may 
be globular, flat, oval, teur-tluped, and of almaa 
every solid form, at will be ie«a by tbe fuUowIm 
engravingi :— 

\ s s 4 a 6 

® % ^mfs> 

7 & 9 lu II 



13 



14 



IS 



IC 



I. 1 i 

17 \*mmi 




I. Heed of th« P«&. SI. Of Ui« Kt<)iifv > 
lV>n*Ulit pAluttn*^ 4. Of Uie Flaa. t < 
Wttrt. It ur Ifafi Tau»oy. 7. The h»irv 
fi- Pitted M'cd of Ibe Scuip-Dra^.in. 9. Of - 
lU. SbffU-liko need iif (he CiDque-rulL i 
r.illnn Plinl. illia Phyaoetcmon.j If. S.. 
Kilt. U. Th« riljbod»e*d ofibe tloMrnuu Dm 
rough H«d (A tb» Krog Bit l». Srnl i>r (be 
16. Sp0<1 uf OD« apecWs of lh« IxJViutUlfe 
i«ed uf Lti* tra-ni^k Stock. 

It will be seen from (he above bow the turlu»tf 
seeds ia variously marked and ronghejied — and, aa 
TD the rose tree, covered with hairs, la the cottoa 
tree they are enveloped in tbe fine, long, and whibs 
down, which is wo well known as cotton } and if «« 
consider still as secda, rather than aa seed-vesadk 
what are commonly called such — namrJy, tha 
produce of the grasses, the compound Aowvn^ 
the nmbellnte plants, and some others, we shall not 
only grcAtly increase tbe number and vnrircy of 
aha|tes which they aaatime. but have our attcntlen 
directed to sundry curious appeudages, by wtu^ 
the dispersion of seeda is in oumerons iii&iancet 
aasiiitcd. 

Tbe seeds of many plants have attached to tbem 
feathery crowns, called in the singular a pappia. tt 
the valerian it at first remains carefully coiled ^ 
but as the seed ripens it eipanda, and the tccd li 
carried away \ when it finds a moist spot ada[iliA 
to its growth this beautiful little crovrn fsUi «f. 
From the aeeda of the willow herb the crown of 
haire projecta like the feathers of a shuttle-cockt 
opening afterwards like a atar. In the dandelioo 
this pappns is supported upon a stalk, which de* 
vates it above tbe seed. In the goat'a-beard sot 
only is this the case, but each fine hair is itsdf a 
feather — forming altogether one of the moat elegui 
and perfect objocts. All these contrivances are !•• 
tended to catch the wind, tliat the seed may bt 
wafted to a distance. The same purpose is sccon- 
ptished in the feather gra«s, in the clematis, aad 
still more perfectly in the tilhndsia, a jilant of tro» 
picol countries, by a long feathery awn. Tbe 
of many of the gmsscs iirnl such like plants hav« 
tached to their lower cod, strong and hXXS br: 
called k*ta'. Theae pointing oil (.me way prevail 
the teed rt turning, when by any cause it has ororkel 



MAGAZINE OF SCIENCE. 



IS 



ig the ^ound, or tmoog the rlnda. Thii 

oftcD (X'CMsiotied by cbungr uf Jf7nrsi and 

l^kn tbeair. Tlte animated oat (ovcnafatan 

,) U a welMuiown example of H. If 

ftcerls be placed upon a shelf or window 

in^Mble weather, it wtlU af^rr the lapse 

Ibrre Jnyt, be found to hate crmwled for- 

« cAitsi livable dtstanco from its first sita- 

'fblloffft : — When the seed becomes damp, it 

' lengthena. 'A'hen the air dries it again, 

ahorter. but on accoant of its aetK, it 

turn ; therefore it draws the latter cud 

thiu aC every change in the weather it 

Ibrward. 




[Pxpmii of tfat Vklerlan. 8. Oitt* of the WillAw 

mm CirunndML 4. OiiOj oT lb* Ouidvllon. S. Ditto 

Wt Bcsnl. C. Fraihrr ot lh« Cl«mAlU Sre&. 

lh« Son^tit. ('f ituU Kuib. & tlainftf tbt Adi- 

i- Ann. <-r uwitwd brltU* of Um Barley OnM. 

the case too with the aim or beard of bar- 

rb<*t. which are set with tcetb like a aaw, 

ly the leeda of these plants, but the 

wiU crawl away from its pareoC, if broken 

" known to children, who gather the 

loa barley graw, and putting one 

;, at the wrist, soon find it at their 



admirable contrivancea for the dis- 
i re are many more to be looked 
nid peculiar formation of seed- 
ing ulten assist in accomplithing the 
Lbeir fur and wool catcbea the hooks 
tteedsof the goose-grass are provided ; 
[the mistletoe adhere to whatever may 

ioK to their clammineaa. It ii well 

ii that the seeds of numerous berries and 

it will grow, though tbey have passed 

bodies of the birds which bare swallowed 

toa we not only witness in seeds them- 

Bost admirable stracturea and contri- 

theirwH)-b«Mng, but the very hsbita and 

cf animola are made subservient to the 

lion of the vegetables upoa which 

Aooriihed. 

EVER-BURNING FLAME. 

« lately read at the Royal Irish Aca- 

Mr. G. J. Knox, ' On a Principle for 

•n Ever-burning Flame.' — " A belief," 

in the discovery of an ever-burning 

to have been prevalent in all agea ; 

informs us. that lamps have been 

where they hare continued burning 

■ thousand years, of which mention 

in the works of St. Austin, PlutArrh, 

lens Vivea, Bapttsta Porta, and Licttus. 

idans, who laid claim to the knowledge 

mystfrioufl, pretended to have re-dis- 

r-t fif lbeir construction, which was 

ive been buried in the tomb of their 

Dr. Plott, in a treitiae which be has 



written upon this snbject, alludes to a Ump men- 
tioned by St. Anstln in his book de Ciritaic Det, 
which was bung up iu the trrople of Venos ; and 
to another found in the tomb of Pallas the Arca- 
dian, who waa slain by Tumus in the Trojan war, 
whirh cootinard to burn after its removal from the 
tomb and eipoaure to the air — proving that these 
lamps were not aupphed from any bituminous source, 
or volranir fire. He considers the rc(iui«ites for an 
ever-burniag lamp lo be — a perpetual wick, which 
might be msde of gold wire, or asbestos ; and^a per- 
petual supply of fuel, which he imagines the bitn- 
minous springs of Pitchford, In Shropshire, or the 
inflammable gasea isaning from fissures in coal 
mines, would afford. That such coold fupply fuel 
for a flame, so long aa the bitnminons spring cxislrd, 
or the gu oootinaed to eibtle from the mines, is 
evident ; but it no more deserve* the appellation of 
an ever-burning Ump, than does a fire arising from 
any volcanic aonroe. The desideratum for such a 
IfiSDpis, that it should contain, within itself, a reno- 
vating principta, aach as, probably, dona the lani- 
nnu5 aCmosphrre enoompaasing the body of the sur, 
ftippoaed by Sir William Herschel to b« electrical. 
That electrteity was the principle upon which such 
a lamp could be constructed, having occurred to me 
some years ago, 1 reflected upon the ditfertnt means 
by which a constant light could be produced from 
this source, and concluded that, if by an arrange- 
ment of metals a thermo-electric corrent could be 
produced of sufficient intenaity to decompose water, 
the heat produced by the burning of the two gaaea 
arising from the decomposition, would be aufbcient, 
when applied to the alternate metallic junctiooa, to 
continue the electrical current of the thenuo-electric 
pile ; while the gases, which, in burning, become 
aqueous vapor, might be oonilensed by paaaing 
throngh a long tube, through which, being conveyed 
to the closed vessel in which tlw water bad been 
originally placed, th<*y would again undergo decom- 
position, recombination, and condeasatioa. Such a 
thermo-electric arraogoment has been discovered hj 
Professor Botto, of Turin, who has obtained decom- 
position of water from a series composed of a greater 
number of wires of platinum and iron. To prevent 
the apparatus from acquiring Jn time the aame tem- 
perature, the alternate janctions of the metals, to 
which the beat is not applied, might be connected 
with the pedeatal upon which the lamp is placed ; 
and the pedestal be either allowed to rest in a cold 
sitQBtion, or else be connected by wires with mmdc 
extensive cooling surface." 

CHARCOAL AS A MANURE. 

BY MK. LCCA8, BOTAKIC OARDEN, BCUMICH. 

According to my promise, I now lay before mf 
r««dcrs the experiments I have made in the applica- 
tion of charcoal to another purpose, via. using it as 
a mixture with various sorts of earth. It showed 
here alao the aame extraordinary effect; and all the 
plants that have hitherto been subjected to thia 
treatment have been as much distinguished by their 
luxuriance of growth, as* by the more perfect de- 
Tclopemeot of their individual parts, lliia waa 
particularly the case with tuberooa- rooted plants, 
which, besides their perfect develupement, had also 
n much longer period of vegetation ; so that the 
diffcrt-nce in thia respect, between those that were 
cultivated iu tlieir usual soil and those which had a 
mixture of charcoal, amounted to nearly two monlba. 
I was led lo thia by several trifling dreams t&ncca. 



A vcrj suitable trcAtment iatroduccd into thin 
botanic garden of plunging poU with bulbous or 
tubcroui-roated pUntj taken up PTfry year, for a 
fvw werka afier potting, or till tbey begin to shoot, 
in a moderate bol-hrnl, ccvcriog them «u inch dtep 
with earth, was applied the prevlotu year. A bed 
which bad been us«d for aowing the aceds of tender 
ptinta in pots, and in which charcoal uhea were 
need for plunging them in, waa appropriated to re- 
c«ire the newly. pljuitcd sprciu of ^4'mm, Begonio, 
Oitaerat GlosCnia^ and Scitambeec. The pota 
with these Cubera were plunged to the rim in the 
frame containing tbo chnrcool ashes, and then 
covered over with loose moold from a dung bed. 

Before I proceed further, I cannot refrain from 
recommendiDg this method, which, to my kooT-. 
ledge, has not been long known io German gardens, 
to all cultiraton ; for nothing is more contrary to 
the nature of thotc plants, than to set Ihem in tlie 
open greenhouse to make their first shoots, where 
they are cooaeqaently in a dry situation. Most of 
them, when treated with a gentle equable warmth, 
like that of a prerionsly-used dung bed, will be 
much more fine than if pUced in a higher and drier 
temperature. Watering the tubers before they be- 
gin to grow ia very disadvantageous, and yet it 
would be absolutely necessary if the pots stood in 
a greenhooM : we prevent the evil by making the 
earth in which the tubers arc to be set sufficiently 
damp, only slightly pressing tliem down, and im- 
mediately coverirg them with earth in the dung 
bed. Only wben the Intter begins to dry, it should 
be moistened all over with Uio watering-pot ; and 
this operation should be continued till all the tubers 
bare made sfaoots, and then each can be watered 
mngly. With reap«ct to preserving them through 
the winter, I have to observe that these tubers, as 
soon as tbey are taken in, should be placed in the 
greenhouse, not too near (he glass, and the earth 
covered with moss, by which they will be prevented 
from drying up too soon, and the neceaaity of 
moistening the earth obviated. By such treatment, 
waul of success in the cultivation of these spleudid 
omamentj&I plants can never be complained of. But 
to our subject. 

Theac tubers, plunged in the aabcs, soon ahot up 
ligorooaly. Aa they ought to be grown in a high 
frame In summer, bat which could not be im^- 
nediatcly prepared, they remained io tbls low bed, 
which waa only raised, dug up, and kept covered 
with earth. They absorbed a great dval, and re- 
quired watering every day. "When Ihey were taken 
np, moat of the roots, as may be snppoaed, had 
grown over and under the pota ; tb^y bad pene- 
trated into the charcoal, and grown so strong, that 
it waa abaoliitely necessary to re-plant the tubers 
in pots considerably larger in size. I. of course, 
mixed charcoal with the earth in which they were 
to be planted, in the proportion of rather more than 
half. All the above-named species showed estra- 
ordimuy Ituuriance under this treatment; some 
were particularly rich in their inflorescence, and tlve 
green of their leaves waa much more iDtense ; in 
others, the period of flowering was of unusnoUy 
long duration, so that while others planted in the 
usual soil had Jong ceased flowerins. these continued 
to vegeUte freely. Very small tubers, from which 
in the ftrat year no flower was to be expected, 
flowered very beaotifolly, as was the caae with 
OcMotra atrowinguinca. The AwtdcK, namely those 
with spotted leaves, such aa Caladium pictum, 
C bicolor, C. discolor, C. spl^ndens, C. poe'cile, 



C. bEmata»li^n)uui. C. verfticolur» iiwc., caciud out* 
versol admiralion. Several apeciea of Bkllb^igaa 
and TilUndaia, to which I also added charcoal, soon 
exceeded in luxuriance thoae that were growing la 
common earth. From what waa before said of tbs 
C6ctif it may easily be su^iposcd that Lhcy wooU 
flower well in a mixture of charcoal, which a- 
pcrience confirmB. Hcchtid, stenopL-tdla. whkdi 
rooted so quickly aa a cutting, has since tbritra 
equally well in a mixture of charcoal. Tlic iplendkd 
Mexican euphorbiaa, such as E. faatuusa and £. 
fulgens, showed a very considerable power of gnnrCL 
Orange trees with yellow leaves, having had a Itytr 
of charcoal laid on after the upper surfaoe of earth 
had been removed, soon recovered their greca 
color ; this was also the case with gardenias, W« 
need not be very particular oa to the quantity to be 
aaed, half charcoal may be used withoat injin; 
only care must be taken, as before noticed, that \M 
charcoal should be exposed for a time Io the infla* 
ence of the weather, and the larger pieces remoroti 
and watering should never be neglected, aa dM 
greater poroaity of earth causes it to dry up soour. 

A very interesting circumstance took place with 
an old and very sickly plant of the DoryantiMS 
excdlsa. After thia plant had been falling off tm 
two years, and in reality had no roots but one 4|d 
and decayed one. it was planted in charcoal, sad it 
the course of three weeks it began to shoot, and ft 
since perfectly recovered ; it is growing in a soQ of 
one-third charcoal. 

Fernfe sown on fine lifted charcoal germinsli 
quickly and well ; a number of species come a|i {■ 
the charcoal beds where seed falls, and not ooJr 
Gymnofriunma macrophylla, and PtiTis serraltef 
but other rarer and more valnable species. ^ 

A friend of mine in the neighbourhood of MqbI^ 
uses charcoal ashes for mixing instead of aand, aad 
he assures me that all plants, chirfly hothouse ooeS, 
and among the castas, particularly thoae with pis* 
nated leaves, acaciaa, bignonioit, 6cc., succeed a- 
tremely well, and have recovered wonderfully tetm 
their previous bickly state. 

My esteemed principal, the court gardener, M- 
Seitx, who acknowledges the importance of thi.'* use 
of charcoal, is now putting in practice a number af 
systematic experiments with different sorts af ehtf* 
conl, on all the familie'* of plants, and it will aotf 
be at the conclusion of these extensive obserratiQiili 
which in spring are to be extended to garden bedi^' 
that a well-grounded opinion on the nppUcatioa t$ 
charcoal ashes In general can be formed. 

Geaiin ZHtunff,Jbr 



CASSAVA. 
Casbata bread, cooaqne. &c.. are different 
given to the starch of the root of the mi 
(Jatropha ManiHut, Linn.) prepared in the 
ing manner in the West Indiea, the tropical 
of America, and upon the African coast, 
tree belongs' to the natural family of the 

The roots are washed, and rcdaced to a 
means of a rasp or grater. The pulp is pulj 
coarae strong canvas bags, and thus aubmiC 
the action of a powerful press, by which it 
with most of its noxious juice, ^used by the Ii 
for poisoning Llie barbs of their arrows.) 
active principle of this juice la volalili:. it is 
diKupated by baking the squcexed cakes of 
upon a plate of iron Fifty pounds of the: 



MAGAZINE OF SCIENCE. 



r, wlwetr distilled, nfftirH. a* ftnr. ihrw oanced 
% poteocMuc wftter, posKssiBic kn intolcrftbly 
:M»fr Ms>el| ; of wliich, thirty-fiTc drops brinjt 
ilattUrvd lo a 8U»e ron*lcted of Uie crime of 
cmaied UU death in the eonrae of tix 
ftmid horrible cunvulvtons. 
The pclp drletl In Ibo miinncr aboTC describet), 
iff^Ua tnio luspi, wliiob b«romc hard and friable 
•Wy cool. They are tlien brolcen into pieL*e<, and 
It is tbc aun to dry. In this aUte ifaej afford 
nutriment, tind are hRbilnallj used aa 
by tlie DefToes, ai alio by many white people. 
.ofutitiUe the only provisions laid in 
ri their voytges apoii the Amoxoni. 
vith a little beef or matton, tbey 
"nop similar to that of rice, 
^kes sent to Enrope, (which I bare 
««.ure-,^ are compoaed almoet entirely 
«>fti»« aloo^ with a few fibru of the tif;nrous 
U paay be purified by diffusion through 
-. p«MtDg the milky mixtnre thrv>righ a 
TTTtporating the strained liqaid orer the 
' nt agitation. The itarch dissolved 
rcns as die water erajmrates, bat 
luiTTil. it becomta granalatrd, and must 
'idried in* proper stove. Ita specific gravity 
of the other species of starch. 
Ifiuiuct abtained by this treatment is known 
under the name of tapioca: and being 
dcatIt pure, is often pniacnbed by phy- 
a aliment of easy digestion. A tolerably 
of it is made by heating, stirring, 
pa4«to ttareh in a similar way. 

juice of the root of manioc cod- 

Don a ?ery (i«e fecaU, which it de- 

tif itpoa the bottom of llie vessels. When 

Recantation from the supernatant liquor, 

ijKTcral times and dried, it forms a heautifoH 

vfckli creaks on pressure with the fingfrs. 

eipipa, in French Gaynnn ; it is em- 

br SMDT delicate articles of cookerr. es- 

ftttey^ as also for hair powder, starching 

lo«r, u imported, may be distinguished 

-ffOpt ftod other kinds uf Ktsrch. by the 

oC ita particles viewed in a microscope. 

afilwHcxl. all about UlOOOth of an inch 

and Asaociated in groups ; those of 

ftr« irregular ellipsoids, rarying in 

l«^0Oth to 1 -3000lh of an inch ; those of 

hjre th£ nme shape nearly, but vary in 

l-&00th to l-800th of an inch ; those of 

sepasmte apheres, KlOOOth of an inch. 



rUEL FOR &TK\M ENGINES. 

itt from St. PetcrKburgb gives some par- 

'if a sew foci for steam-engines, discovered 

ired by a M. Waschiuokotf, which 

ll U Asid* P^eat idrantages over coal. We 

r, besrd of so many of these wonderful 

~" oountrr, tbst we are a little 

)>« well to publish the facts 

'-xperiment msde, on a large 

,«iU tcttt toei, to which M. WasohinnkolT has 

lb« ftubc of rarbolein. was on board the 

itmmmr Syrias, on its last voyage from 

to Uoodun ; and the results are given aa 

•ooauiDptiun of-lilb. (English weight) 

is per bour, for every horse-puwer of the 

Uuitfwn revolutions per minute, 

■ speed of more thsn seven English 



miles per hour ; whilst, on the same voyage, wiUi 

ilb. of English rotil, of best quality, the wUc<>l i 
only twelre revolutions, and the vessel miuti 
more than f)\ miles an hour. The flaniA- 
new foci, sayi Captain Wjitera, who 
the Syrius, wai> so great, that they wert 
obliged to reduce it to one-third. — A cubic 
the best Newcastle coal weighs nearly S^itb., 
the same measure of carbol&n weiglis nearly .'iCt 
•t,4SO,0001h. of coal, the usual provision for 
vrsscls passing between England and the Uni 
States, occupy a space oi Hl.HSl cubic feet 
2,480,11001^. of carboliJin yielding the same i 
take only Dl. 094 cubic feet; so that the latter 
biistilile would effrct a saving of room to the e 
of 30.100 cubic fret, aviiUble for mrnhandii 
pasaeogers. The freight from EitgUnd to 
America, and vice versfi. I>t:ing at the ra(e of 2s. 
per cubic foot, makini; b». boLb ways, the 
economized, vrould produrr, for the two pi 
an excess of freight amounting, in value, to £'. 
deducting from this sum i643 (or the greater y 
of the corboU^in necessary for the two voyages 
coal, and allowing, bcsidet, jCl.^tO to the aco 
or any defiriency which might occur in filling 
the space aaved, with goods or paasengent, thl 
would still be a clear gain, at the lowest calci 
tion. of £3,000 by the use of the new fiiel.— 
AtAenatttm, 



MEMORANDA. 1 

Acthn tff Sulp/iur on Tron, — Colonel A. Evans 
has remarked that although sulphur has so strung an 
action on heated wrought iron, as immediately (o 
form boleH in it. yet it does not at all atTect grey 
cost iron. A plate of wrought iron, 63 of an inch 
in tliirkrieds, hrated to whiteness, and held against 
a roll of sulphur fi.lU of nn inch in diameter, was, 
in fourteen seconds, pierced through with a perfectly 
cylindrical hole. Another bnr, about two inches in 
thickness, was pierced by the same means in fif^cn 
seconds. Good steel was pierced even more rapidly 
than the iron ; bnt a piece of grey cast iron, wdl 
scaled and heated till nearly in fusion, waa not at 
all affected by the application of sulphur to its snr* 
face, not evenj a mark being left, A crucible wu 
made of this cnst iron, and some iron and sulphur 
put into it; on applying heat, the iron and sulphur 
soon fused together, but the cast iron underwent no 
change. — j^nn. de Ckim. 

Z^ad On in Glamargofuhire. — ^The Cambrian 
obierves— " It seems somewhat extraordinary, that 
in this speculating age, when such vast sums are 
sent to seek, and too often to sink, their fortunes in 
a far di«tant region, that our home treasures should 
be so disregurded, even our own county of Glsmor- 
gan. Leod ore, of the purest quality, which c&a 
even be scraped up by the sides of the road, in 
ditches, and abundantly a few feet beneath the 
face of the soil, still coniinues to be dormant 
science, capital, the gigantic power of the stea 
engine, all alike dormant. St. Hilary, Colrinsto 
Langan, Penlline, and other parishes, abound 
lead ore. Take up a handful of earth near any of 
the old pits, and it Is fall of lead ore. Twenty-iive 
years ago, it was asserted by tlie oldest pergmis then 
living, that the working of the lead mines on the 
PetiUine Court Estate was suspended (now from 
eighty to one hundred years ago) in conM^queoce of 
the overwhelming prcMure of water, years befu; 
the iteaa-eDgiue, with iU gigantic power, came ' 



ut 

i 




play, and Cfaat the mun vein of ore at Uie liine was 
Ihirijr-sPTen inchei in tlucknua. The ore waa then 
carried above half a mile to be waahed, and taken 
bark again to tbe Rmelting-honae, which adjoined 
the pita. Tbe iteain-engiae would now admit of 
the ore being washed U)K)n Che spot.'* 

GotJ, Sitver, and Copper dnn, — The folloffiog 
ia the number of pieces uf various sort* cuiiied at 
the Mint from the Isl of January, 1H37, to the 
31st of December, 1840 : — SoTcr«tgns, 4,395,373 ; 
half-Rovereigoa, 43-1, 77M ; — crowns, nil , — half- 
crowQi* 567.072 ; — ftljiUings, 9.74l,l}00; — liz. 
pence*, 7,524,000 .—fourpcncei, 6,070,680;— (the 
(otalQumbcroffourpcneesiaaucdbciitg 10,325,320 ;) 
penoe, 174,720 ;— halfpence, 1,075,200; — and 
£arthinga, 10.913.280. 

Coat Dust a* Manure.— Mt. W. H. B. Webster, 
Surgeon, K.N., of Ipswich, baa paid aome attention 
to this subject, the details of which may be found 
in tbe last part of the Transactions of the Society 
of Arts, London. The analogy twtwecn the con. 
atituent priuciplea of coal to that of oily matter led 
Mr. W. to conceive that it might be advantageously 
employed as food for plants. Tbe complete insolu- 
bility of coal dust aeems to be the Inwparable 
objectioD to its utility as ii raanure. and Mr. W. is 
inclined to beUeTc, from a long conitnued series of 
'observations, that tbe slender fiUmeutous radicles 
of plants (in other words tpongeoUtt) liave a power 
in all reapects equal, if not niperior. to small electro< 
galvanic wires of low intensity, which, by slow con* 
tinucd action decompose most substances that are 
presented to them, end among others that of coal 
dttst. Mr. W. also further states, that, whatever 
the Tital principle may bo, a lower grade cannot be 
aasigned fur it in the scale than that of electro- 
galvanic infloeoce ; and we are not, says he, 
Msuroiog too much for tbe TiCal action of the 
radiclea, when we -claim for them a power etjual to 
that of amatl galvamc wires, which can and do 
effect a deconi position of coal dust. He then pro- 
ceedfl to demonstrate the fact, that coal dust is not 
inimicat to vegetation, and this he accumplishes, by 
filling a series of garden-pots with fine cotl dust, 
and planting and sowing b variety of plants thrrein, 
as potatoes, onious. Sec. In all of them the vegeta- 
tion was estrejnrly vigorous and luxuriant. He 
also filled hyacinth gUsscs with coal dust, and put 
bulbs therein, supplying water as required ; and the 
result, when compared with tliose without tbe coal 
dust, was very marked and evident ; large, healthy, 
strong plants being produced, and admired by many. 

Animalculen contained in CAaro.— Thuret has 
observed in the interior of the anthers (globules) 
of chara mtgarii and C Hitpida, AexuoHc. Iriins- 
jiarent, chambered filameuta of unequal length, in 
which are containtd animalcules at fimt niotionlL-ns, 
but after a time they move and struggle to release 
themselves from tlidr prison. In this they do not 
always succeed, although their twisted position 
attests the eflbrts mode far disengiigement. Tliey 
appeared like a spirally-rolled thread of three to 
6ve curvea, with two appendages, briitUes, or ten- 
taeuU of excessive tenuity, which the animalcule 
incesuuilly agitates with great rapidity.— A/icro- 
Bcopic Journal, 

Air contained in Snov. — According to Dalton, 
the quantity of oxygen in the atmonpherc diminishes 
in proportion to the distance from the surfHce of the 
earth. Gay-Lussac, however, did not find this to 



be the lesult of hia experimenta — foi\ir whidilM 
obtained at a height of upwards of 2U,0Oi> i-^'-t r^ 
taincd the same proportion of oxjgcu n- 
cured from tlie nrighbuurhoud of P*its. 
singauU has found, iu common with oUicrt, lu*; «r 
obtained from snow contains 1cm O-tygen th«n tiiat 
of tbe atmosphere. Bat this holds good with rcfarl 
to tbe suow of the Andes, as to thitt of I'siii. U* 
admiti, however, that this may not be the composu 
tion of the air as it eii«ts in tlu: luuw ; bcesuse, Ui 
onlur to obtain this sir, it is iieceasary to mill ttut 
snow ; the gas of Cht- flask coiuea in contact with tbi 
wattrr, little if at all impregnated with air n-«nluttf 
from the melting, and it is wilt kno-->' 
such circumstances oxygen ditt&ulvcs mur- 
water than tlie asote, and that thr -•' 
water is saturated is richer in a\> . 
the atmosphere. M. Duinai and ' . 
are at present examiniug the cunpoailiou of atma* 
spheric air. — j4Mcn(pum. 

Briti»h Muttum. — The numl^er of ^i 
mitted to view the general collections fr< 
mas 1H39 to Christmas 1840, amounts u> ^\.,j,j, 
being 32,921 leas than in tJie previuui: yenr. TU 
number of visits made to the reading room*, im 
the purpose of research or study, during the fotf 
year, amounts to 07, •'i42, being 1,G74 less than hi 
the year before. The number of visits by artists 
and students tu the galleries of sculpiure. for the 
purposes of study, amounts to 6,354, being uk 
increase of 1,013 to the previous year. Tbe num- 
her of visits made to the print room, in ImQ, 
amounted to 6,717. The total number of additioui 
to the zoological department, by parcliaac ur othn- 
wice, 21,976 specimens. — Report, Houie qf 
ntons. Match 8, 1641. 

itff/eoric Paper. — TTie microscope has 
empluyt'd by Ebrenbef^ to determine the oo 
tion of the meteoric paper of lOliG, and w 
states is a product of eot\femm and ii\fu»orwat 
existing on our globe. According to this 
tbe substance known by the name of meteoric 
and which fell near Rauden, in Curlond, in 
is formed of ^laments of cortferva critpat.. 
matted together, Wwix remains of a noal^j 
nine well-prntcrved kpecifs of infusoria, miu 
cosca of dapfmia pitlrjc. Vf the twenty-nine 
soria eight only have aiUcious lorictt ; the r 
soft coverings. In the meteoric psfier of 
seoberg, Ehrenburg found eonferra eapillA 
punctaliit and otciltaioria timota^ along with 
distinct species of infasoria, tec. In a mass 
in Sweden, (Edogomum ceMtcatum (Link) loi 
and the- potten of some couiferte were discovi 
Microtcopie Journal. 

Preserralion of Meat. — At the last roeeci 
the Academy of Sciences, M. Gannal presen 
important essay, which is hkely to produce a 
derablo sensation amongst the public as well 
the scientific worid. M. Ganoal bos been for 
years occujiied with the idea of preserving mi 
injection. Thus, 4tb. weight of saline mixturff 
jected into the carotid artery of an ox penetrates 
■ he vessels, and prevents a putrid decompotil 
M. Gannal presented two 1^ of mutton 
two years since by this plan, and which i 
to be perfectly sweet. M. Gannal eraploya for 
purpose muriate of alum. This discovery is 
sldered ns valuable in prcaerring provisioua for 
nsTy. — Timt9. 



Lowmiw^PrinK'l by P. rsAHOk. fi. Wmt llono Lai>«. MtlP Eud — I'uhlixheil tiy W lUirrAi^. 1 1. raWratN«i»f Hi 
Cuinni4aitrsli«>ua. (»ltlch are 4iMntfivU uo Iht W(d)(|>cra of ibe I'artfj to hi adilrcueU to tlie k:ailc>r,a[ S^,(i(«a1 1'rruvtl 



AGAZINE OF SCIENCE, 



Unt School of ^xts. 




18 



MAGAZINTS OF SCIENCE. 



THE GAS METER. 

Pom (be invention nf this niftrhiae wn arc indchtrd 
to the innenaity nnd tolrats of Mr. Cltq^, mad ua- 
doubtcdly trf all the uiiprovefneut* wilb wbich the 
art uf prvcoring light hu been enrichctl, there ia 
none which has been attended with reralti more 
bencAcial to the inierat both of the nuuitifactartr 
Kod consumer of coal gia. 

In thin nischint! we Me coDibtocd ft itandard or 
cheek on the cutidiict of the workmen, which enabled 
the monufhclurer of coftl gv to BMore himself of 
nhtJiiuin^ at lUl timet the ^reate^t poacible produce 
firom bis estahliKhment ; s me«5Ure by which hr raui 
deal the ^bm oat to his costomers in whaCerer qnan- 
titu* they may reqoinc it, and an Index which re. 
psters the exact qnantities fornished, and tfauj serves 
u an infallible account of debtor and creditvr be- 
tween the seller and purchaser of gas. 

Tlua machine, therefore, perfoima at onoe all the 
dntim of an overaeer, meter, and book-keeper, and 
performs them all an mnch more effectooUy, thai ltd 
operation is not dependant on mattera ao onceruuu 
aa tite care or iDtCffhty of aervonta, but on onerring 
priociplea, whit^ are fixed and incapable of any 
hidden mifl«ppUcati(m. 

Rg. 1, representa a perpendicnlar section of the 
gaa meter. It eooiisti of a hollow wheel or cylinder, 
made of tlnn ixtm plate, revolving upon an bori. 
■ontal axis, in the manner of a grindstone ; thit 
wheel b hiclosed in a cast iron air-tight case con- 
taining water. 

The cylinder, or whed, is composed of two cir- 
cular channels, concentric to each other. The larger, 
or outer channel, is divided into tfanw equitl com- 
partmenta, by partition plates, marked, aa »hown 
in the design. The compartmeuts are proviHedwitb 
hydraulic ducts Of valves, mode at the upper port of 
emy pwtitioD plate A, A, A. and by meona of them 
m oommimication is formed between the larger con- 
centric channel and the outer case in which the 
wheel revolves. 

Similar valreii are also placed at the foot of each 
partition plate, they are aeen near the other letters 
A, A, A, and by thia means, a communication is 
rstjihlishcd, brtwcm each compartment or cliaiuber 
of the larger concentric channel and the smaller in- 
terior circle of the wheel. 

On ioffpecting the dt-sign, it will be seen that the 
valves are situated in o|iposite directions to each 
other, hence there can be no communieotion either 
between the inner smaller concentric channel, and 
the larger compartments of the wheel, nor between 
the latter compartment, and the exterior caae, in 
which the wheel revolves, except through the valves 
A, A. A, Ace, which form thf oom muni rating ducts. 
It will be aeen also, that theae valves are carried 
from one chamber of the machine into another, but 
in opposite directionti ; the entry into one chamber, 
being in the oppoeite direction to the hydraulic 
duct, placed in the other clumiber. 

Prom these particulars the action of the machine 
will be obvious. 

l^t ua suppose that the outer case (which is 
marked in tlte sketch by a black tint.) in which riie 
wheel revolves, be filled with water, to about on 
inrii above the axis of the whcd, and that gas is 
conveyed into the interior small cliiunel, by n piyte 
passing along the axia, so as to allow the wheel to 
turn freely round, and that the pipe is turned op 
at right angles in the inner chamber, and projects 
A \'tt\c way above the mrfarc nf the vrntcr, as 



ahoam in the design. Hie gaa then ma] 
into the interior rhamhBr of ihc wheel nbi 
surfane of the water, and Dtn%t prr»a ogaiiiat 
jacrut partitiuD ; it will therefore cau>e tli 
to turn round, and in coiis»jucnoe of thia 
the next |uirtttiou plate will prra« the gaa 
the surface of the water, and i-auj-cr it u> pua 
the hydraulic opening, in an r<)itnl i{uanttty 
which is introduced into the exterior * i.:>.nlii.| 

This alternate tilling , uiid diat). 
contenta of each chamber, will ih-. 
during every revolution of the wjjfil. 'uj r,. 
number of tttuea each particular ch.in.ir l 
hlled, and emptied of ga», may be ku'.s u. 

In fact thit maciune perfurms the t-lliri- n 
revolving gas holdera, tuni on an ) 
and moving in a dateru. which is li 
the machine. One gas holder, or l>[j 
of the machine, is olway* in the act of li| 
filled with gas, another is emptying ltd cootdj 
the outer c««e, from which it passe* into thjl 
voir, where it is to be stored up, or to Cht 
where it is to be burned, and the third compl 
is stotioaary, or in on equilibrium. The W 
any situation will* therefore always have one 
receiving, and one of its discharging toIvci 
and consequently it will revolve. 

Now to ascertain the quantity of gas dim 
by one revolution of the wheel, we need ( 
know the capacity of the chambers, and ad<i 
together. Let us for example BUppoae, ihi 
chamber contains 576 cubic inches, then on 
lution of the wheel, discharges a cnbic foot 
To register the total number of revolutions 
the wheel makes in a certain time, a train of 
work is connected with the axis of the m< 
LtiiuctKti of a pinion impelling a common t 
wheel- work, comfio«ed of any number oi \ 
The pinion on tbc axis of one wheel, 
circumference of the next wheel, an 
ference of tlu* wheel being as ten to v. 
whilst the meter makes 1.0UO,OOOrt-^ 
sent-* consistx of »ix wheeln, the lu>t 
series will only have mode one re\ • 
axil of tlie wheels is provided with a i 
plate, divided into ten parts, therrforv on) t. 
of nn-olutions may be read oif at any time 
apcctiou betwixt 1,000,000 ajd 1. (See Fig. J 
The velocity with whiiih the meter acCi, 
counse in proportion to the (|nantity "f cr-* i 
through it. Thus snjipose there it .- 
lamp connected with the machine, ol 
city Ughled. which consumes four Cuba fc«c 
in an hnur, the gaa mctt r perfnrms foor reto 
per hour, not exceeding the number wtuch ti 
chine is calnilated to supply. 

To render the contttrurtion rf the gas 
more obvious, we have ot Pig. 4, ethibiled u 
verse section of the machme; K ti tlw nuto 
of the machine in which tlie wheel revolves, 
the outer or larger concentric chamber. M tbt 
or smaller concentric chnmber. I) the index 
axis, which passes tlirough a stuffing box m ft 
the mochuu*. A Is the inlet pipe for the | 
enter into the machine. The gas passes di 
the pipe C, and ^om thence into the curvu 
D, into the interior chamber M, nf the I 
The pipe H, Is surrounded by a second p4 
which has a small aperture nt X, the office oif 
is to act as a ^phon, in order to preaer 
proper level of the water, which is poured M 
innvhtne through the funnel at tlie buftj 




MAGAZINE OF SCIEXCE. 



19 



ice f{p« A. Y is a flout, which stopi the 

lAQoe of ttw m^-trr alto^ethrr, if a fraudulent 

ipt sbould \te nittde to »tap the retnsteriiij^ of 

meCcr, by drnwiug off the watrr with which it 

iJirKed. In Fiff. 1, C ii the inlet pipe; D the 

pipe of the )^u. 

► GaM GoperMur.-^Viff. 6, is an instmnaent 

ited br Mr. Cleif]?. fnr rej^lntinn the inequnlitien 

«n the irreinilur prPAsiireofthe ;ft5-bnl(lcr«, 

tbftt from th^ {itiTtinK out of tlic Ug^hU nt 

tH-HnH.i f.f the night. This contriTiincc 

CMotnettT of sufficient weight 

[Dirptl pressure ; the interior of 

;t t-\iu\itiunicAtloii with the pipe tbroagh 

gti pitymm. This prwiomrter is connected 

rntvr, sn thftt when the pre«snre 

I, the gmomctcr risc!) and con- 

and, cm the cuntrarf, if the 

I the guomrter (altx and inereaMtM 

everjr case, the aperture is always 

tth the demand, presrrvint; the flame at 

height. Ita purposes are more eflertually 

»hnl by placing one, on a small sode, in 

hotiMT ; but one on a large scale, placed at the 

nutlet at the ga:9 works, will eqnalize the 

prr»are, and sevnis to be absirlately ne- 

iet.^«. -nremors are not indfridiiftlly used. 

-acting machine, and requires no 

■I once adjusttrd. The following de- 

m will probably render it intelligible : — 

6| is a section of the governor, and A B ex- 

jter ease ; this is made of sheet-iron or 

the top and bottom dosed, and bnth 

and nutstdi^ are al^o japoimcd. C shows 

'm tif the small giuometer. D the pi|« by 

the gKi enters ; and E the pipe by which it 

out. Tlie conical valve attaclied lo the 

uf llu: npright spindle I, risi^ and fnlls, so 

or enlarge the aperture G, as the 

nceiuls or deiicendfi by the entrance or 

of the gas ; and H is a short hollow 

eeji, in which the outer caae is fixed ac 

;of Its ha5«. 

has made some improvemenL<- in the 
. of the governor for regulating the supply 
owlet of the works, %o that, by its own 
pii'nure is increased or dimini.«ihcd with 
I Oni; of the modes he em- 
irtion of the small gaMmcter. 
».''>, iiy making an experimental gas* 
a small scale, ami requiring; luiifonn 
comparing the intensities uf light, in- 
a compeiisaiion chain, which it is not 
free from friction, he found that he 
the fiune, in a more shnple way. by 
giMHoeter leas in diameter at the Cop 
biHtom. Hence, by incrcjuiuE; this 
ice. tJir gwometer may be made to vary its 
Jo any required degree. He also effects 
irpo5e by employing a gawmcter of the 
instruction, making the necc*-!Qry com- 
tneans of a cycloidnl whfel.over which 
■-wriirht is itiapendcd. This wheel ia 
■ pegs for varying the curve, 
■ uro to any required variations. 
nioiiinrationB of the governor, Mr. 
I ftlmdy rendered it capable of regulating 
r.f .r*. fVom a portiible gas vessel, so 
i-tment of the valve, the flame 
from the beginning, tlirough 
of preanire, from thirty atmospberea 
of conimon gaaoiuetcra. 



The Oat Renter is a simple and iHgeninos in< 
strument for Indicating and regirtertng the impori* 
ties of the gna, and which, at the Mme timCt denotes 
the periods when they occur. 

The arrangement of this apparatus conftitts of a 
circular card placed upon an axis, which commoni- 
cntes with a time-piece. Upon tliis card tliree 
circieji are described which are divided into 24 divi- 
fions by line* drawn from the centre, corrospoDdiDg 
with the hours uf dny and night. The two largest 
cirrlex, {\ B, Fig. .1.) which arc of equal breadth, 
otrcupy the marginal ipace at the outer extremity of 
the card ; these ore coated with the usual solutions 
or tests for sulphuretted hydrogen and ammonia, 
and a very small jet of gas, from an oritice adapted 
to each of the circles, is made to pUy constantly 
over them. The inner circle being divided into 
.•ipacett that are marked from 1 to 12 fnr day, and 
1 to 12 for nigliK, hence, as the axis of the time- 
piece performs its revolution with the card attaclied 
to it, the impurities, and the time when they happen, 
become exactly registered ; and by changing theso 
cards daily a perpetual register is obtained. Tlie 
principle on which it acts renders the managing of 
it readily attainable ; and ita utility U obvious. 

Specie Oraritt/ Apparatut. — Another valuable 
addition to the apimratni reloting to gas, for which 
the public is indebtcil to Mr. Croaley, is a very 
simple and efficient cmitrironce for ascertaining the 
Mpeeijir tfrwity of corbnretted hydrogen gu* which 
he has acoomponied with an appropriate table for 
rendering the calculation easy and concise, at dtflcrcnt 
temperatures and hai-ometricat prcasures. Fig. 5, 
is a figure of the instrument, and the description 
annexed is copied fniin Mr. Crosley's, 

The specific gravity of carburetted hydrogen goa 
being one of the lending tesU uf iu illumiuatiaK 
power, the following easy method of ascertaining it 
is submitted for the use of thoae who are engaged 
in the management of gas-light estabUahmentft:-^ 

The figure represenU the form of a flaik, with 
an opening and cap at each end, which may be 
completely dischargNl of tlie air, and filled with 
gas, by placing one of its ends upon a pipe or coclc, 
of the same size, and passing a current of gas 
thrrmgti it in the following manner:— A projection 
is placed on each side of the flask, by wliich it is 
intended to be held iu the hand, so that the tempe- 
rature of the gas or air within may not be increased. 
Previously to the flask being filled with the gas 
intended to* he weighed, let it be freed from foul 
air, or gas, by taking off the caps from each end, 
and passing o current of fresh air through it, until 
the air within is the same as without ; this may 
be easily eflected by moving it quickly and repeatedly 
to and fro, endways, in the air ; the caps nmy then 
be put on, and the flo-ik arcHrately balanced; this 
being done, take off the caps, and past a current of 
goa through it during about ten seconds of time ; 
then put on the cap at the upper end, and, at the 
instant of disengaging the bottom end of the' fla&k 
from the pipe or cock, put on its cap, and im- 
mediately weigh it again, when the diminution, or 
counter- weight, required for restoring the balance, 
will give the specific gravity of the gas. 

TO OBTAIN PURE PLATINUM. 

Platinum is found in the metallic state, in small 
grains, in South America, confined to alluvial 
straU, chiefly in Brazil and Pern. It has alto been 
found in the proviaoe of AuUoquio, in North 



I 



■Ok 



tf 



MAGAZINE OF STTENCE 



Anirricit; ami in eoiuiderable qiuntiticj in the 
tJrnltan tnouotaiiu of Siberin. The grains, bnides 
piNtinum, rontnin prnrrally gnid, iron, le«d, psUa- 
dinw, rhodium, indium, ftnd cMmium, utA often 
flitdt* of titaniam and chromftte of inin. Roandcd 
raB5*pft of the ntiHal, howrver, ncrnsionaUy occor 
among them, and are tnrt with in mineral col- 
ffftions ; thr^ are rnrcty larger (ban a small nuirbic, 
tbouj>h some huvt been found of tbe size of a 
pi|;con'i e^ and upwards. 

The pure metal may be obtained br diasoWing: 
crude pUtinnm in nitro.roariatic acid, and prc- 
cipltatini; by a solution of rnuriate of ammonia. 
Thtr firit precipitate \» heated, re-dinsolred io nitrn- 
nuirinlicanid, and sfrsln precipitated h% before. Tbe 
icc*ond precipiute ia heated white-hot, and pure 
plntitium reniainii. It if a wUite metal, rjEtremely 
difficult of fusion, and unaltered by tbe joint action 
of heot nnd air. It Tarie? in density from 21 to 
21.5. According to tlw dci^rre of niechaniral com- 
prcsBsion which it has nu^taincd; it ia extremely 
durt!Ir, but cannot be beat«n out into itucb thin 
FeavcA on gold and icilvrr. 

The follnwins: details respecting the mode of 
puriryiiijn; plnlinuin, iind renderini; it nialleable, are 
t'ikcn from I>r. WoUa'«ton's hitc^t pnptT upnn this 
subject, published in iha Philosophical T^-aiiaactioTiM 
for 1829 :— 

*' Tbe Ofual method of giriof chemical purity tn 
this metal, by solution in nqua rcpa and prvcipi- 
tatioD with tal-ammonioc, nre known to every 
rhemlst ; but 1 doubt whether sufficient care Is 
ti>uiilly tftlcpn to Rvutd dixsoUini; tht iridium con- 
(..;. ...I ... I, ,> oi-p^ jjy ^jyg dilution of the coli-ent. 
I .t which I (p»ve in the Pfiiiotitphicat 

T V for IMO-I, of n new metal, rbodium, 

contained tn mide platina, 1 have mentioned this 
pre«:Aution, but omitted to state to what degree tbe 
acidfi should be dilutnl. 1 now, therefore, rccom- 
luend, that to every measure of the strongest 
riiurintic acid employed, there be ndded an equal 
nipj»*nre of wnler ; and, that the nitric acid used 
be what is called •' sin|-le aquafortis ; " as well for 
ttie suke of ubtAinitiff a purer result, as of eoouomy 
in the purchase of nitric acid. With rt-frard to the 
prnpDrtions in which the acids are to be used, I 
may nny, in rrmnd number*, that niuriiitic acid, 
C<)(iiralent to l&O marble, together with nitric ucid, 
e«|mv«lent to 40 marble, will take 100 of crude 
platinum ; hut in ordi»r to avoid waste, and render 
the snhition pnrer, there should be in ihe menAtruum 
n redundnnre of 20 per cent, at leant of the ore. 
The acids tfhould be allowed to diirest three or foar 
riaya, with a heat ^aduHlly raised. The salulion. 
bein^ then pourrd ofT, should »tand until a quantity 
of fine pulverulent ore of iridinru. suspended in the 
liquid, haA subsided ; nnd Bhould then be mixed 
with -tl parts of flaUammoninc, disftoked in about 
five times their weight of water. The first pre- 
cipitate, which will thus be obtained, will weigh 
about Ifift parts, and will yield about 6ti parts of 
pare platinum. As the mother-liquor will still 
contAm aboat 11 partif of platinum, tbe^te, with 
some of the other metals yet held io solution, arr 
to be recoverwd, by precipitation from the liquor 
, ..;. ..I ,.. v..^j ^ vroTi, and the precipitate is to be 
i ill A pro|Hjrtiunn1r qnnntity of aqua 

r'_ , I ir in lU eomjuisition to that bIkjvc 

dtm^trd : but in tbiu case, before addioi; sal-ammo- 
niac, abimt one part by mcanurc of strung muriatic 
acid ahouhl he ntixed with 32 parts by measure of 
the nitro-murutic solution, to prevent any pre- 



cipitation of palladium or lead aloag with tk« 
ammonio-muriate of pUtinum. T^i- t.Hi.^v Tire- 
cipitate mnat be wpII washed, in '<? U 

from the Tarioua impnrittcK «hirh n^ . i<i b« 

contained in the coroplir-ittcd ore in queauon , and 
must ultimately br well preflinrd, la order to remove 
the lost remnant of tbe washings. It ia oeiC to b« 
heated, with the utmost caution, in a bUck-I«Sid 
pot. with so low a beat as just to expel tbe 
of the sal-ammoniac, and to oceasloA tbe 
of platinum to cohere as little aa poasiblc; 
this depends the ultimate ductility of the produrL 

" The grey product of tbe pUtinum. when tarmd 
out of the rntrlhle, if prepared with due cautioa« 
will be found lightly coherent, and roost tbra be 
rubbe<l between the hands of the operator, in order 
to procure, by the gentlest means, a> wuch u CU 
poftHibly be so oVitained. of metallic powder. M. 
aa to pass through a fine lawn sieve. Tbe 
parte are then tu l>e ground lo a woodro bowll 
a wooden pestle, but on no account with tay' 
material, capable of burni«biug tbe partiele* 
pUtiutim ; aioM every degree of boroisbiiig »iD 
prevent tbe particles from rah^ring in the further 
stucfs of the proccM. Sim.-e the whole « 
tn br well wAshcd in c)e)in water, the < 
the Utcr stages of grinding, will fm'i 
facilitated by tbe addition of water, m order so 
remove tbe finer portions, as ^<oiia m they are nfi-^ 
cicntly reduced to bo AUipendcil in it. 

•• Those who would view this aubjeet arientlfi- 
cally, should here con^-ldcr. that ai» platin' 
be fused by the utmost hmt uf our furi 
consequently cannot be freed, hVr ■•' 
frnra itA impurities, during igneous ' 
nor be rendered boitioneiieffus by h 
mechanical diffosioD through water .sho 
mode to answer, as far aa may be, the ; 
roeliing ; in allowing earthy matters U> c 
surface by their superior lighlness, and 
tbe solvent power* of water effect, oc far 
hlc, tlR* purifying powers of borax mad otbtfl 
in removing Boluble oxides. 

" By repeated wafibing, shaking, and 
the finer parts of the grey powder of plstinnm' 
be obtained aa pure u other meiak are ti 
thf^ various proceasea of ordinary metalli 
if now poured over, and allowrd to s-. 
clean basin, a uniform mud or ptilp will 1 
ready for the further prtweaa uf casting. 



DIMINUTION OF TEMPEKATURB 
COASTS, SANDBANKS. Ae. 

In the third number of the Journal of 
the Arts, an extract of n letter from Dr. D»< 
been published, eoniainini; some obscrti 
the temperatnre of the ocean and atmosphi 
the equatorial regions of the globe. Amoogitj 
philosophical remarks, those by which be eofl 
the conclufion of Mr. Jonathan WilUama, an4j 
observers, that the teinpfratmc of the 
lalls in sbiuil wiiler, ;ind that the thrrmomct 
be made a useful instrument in Da\iga(ioo» 
to be very important. 

Mr. Witlinms attribate« th*- effect npoa the 
mnmeter, on tite approach of land, to the 
power of the land ; but this n»son will DOtil 
to the effect of shooU in the oc«tan, or to the 
i?a1 climates. M. de Ilnmbold, in bis 
Narrative, seems to couaidci it us restillili| 



rflte 



MAGA2INK OF SCreXCE, 



21 



[ciM cnmnka Mow the suif&ce ; bat 'm kii work he 

,jioc cuter into my miriule details: nor did he 

it ftjiy turtber, thui to mautiontng thiv gnne- 

ihtioti Dr. Dary hu merely noticed the fnoC, 

ier«l Uw ; bttC hju not ipecukted u(M>n tha 

tof it. 

raya produce very little heat, in paistng 

eir; hot during their trarismiuiun 

body M imptrrfci-tlr traruparent as water, 

am Im no dmi1)i thnt th« sane oaaie which 

loos fth>aa "• !"■'■* —n^t cororounintc ui etTect 

sf bCBl;. Hid ccM the i^mtejit heat inuat 

laeed at '. nf the sea, and it muat 

ulty diminiah, as the rays penetrate deeper. 

itt heal of the aurface of the ocean most, at a 

:diJlaocn from land, depend upon the ahiwrp- 

the witar rwy«. xhr eooling of thi« surface 

.ind upon evuporatlon. 

'■nn»Iiictor of heat ; and 

-e .«. -r ...- „. W of Fahrenheit, its 

terreaaed : when cooling af^nciet act 

^vnfiltliomable ocean, the atrata of water 

'^Vlnk Ant of the reach of the surface, and 

inrtniinre the tempernture of Ihia <iurfnre; 

ioUd]^ aieencies act npua a shallow part 

I, the couled strati accamulute and up- 

■r the Hurfacf, and cause the tcmjiera. 

ocean, bt \ti surface even, to be nearer 

tmpenttnre of day and night. 

shallow water, close to the shore, the 

be heated ; and durinir the day the 

dose to the shore, will be higher than 

ocean ; but in tlie night, as the land 

than the sea by radiation, the air, haTiiig 

tare lowered by contact with the cooled 

down upon the sea, and thuii will deKtruy 

the hot watrr flowing from the extrente 

at a L-t-rtnin moderate distance will 

a diniiriuliun of temprrurure, as will 

oomprnsate for the heat prodaced by 

bot land. Hot-air and water, witbin 

i»2^ always rise ; water cooled below 

Its ; therefore, by whatever cause cool 

arv kept near the surfuce of the ocean, 

will dimimsh the general temperature of 

[Mrlboc. 

snpposed by M. Perron, and other 

tt tee may exist at the boUooi of the 

simple physical reaimns show thnt this 

tuibit:, itoless the temperatnro of the surffice 

vvc^n in below 40"^; lor water at 40^, is hca- 

^tltaa at tlie frceiin^ point. Ice, as Count 

lias shown, olwBjrs forms at the surface; 

at tbi' txittom of soy part uf the ocean, must 

ttii Itisw, when the temjKTBturr. of the aurface 

40^; fur hot curreols then descend, and 

riae. 

ir caoM must always operatCi when the 

ke snrfdce of the ocean is above 52*^ ; 

these circumstaoccs, whether in the equa- 

polar, or tropical climates, Und or sballuiirs 

•|v4fa lower thr tpmpcr.«turc oi the ocean : 

li latitudes, if the heat of the surface 

ti'' 11 Co 4U'^ oiily, Uie Uiermomcter will 

ifunKri iir .1 gnide of land tn the riBric;Htor, for 

if hearier at 1 7". ihaa at the freezing point 

hat such ao occurrcooe can only happen in 



HOW TO STUDY CHEMISTRY CHEAPLY, 

BT jaMcs HKantaT cookk. 
It is a common opinion, that in order to study kdj 
acience practically, a per^nn mast ofCfManly incur 
a great txpetiae ; thnt this in, to o cnruiin orient, 
correct, cannot be drniird. nn the hi^htr branches of 
every science frequently reiiuire tnitrumeots of ■ 
delicacy snd einctness of construction far beyond 
the akill of the experimentalist himself, and which 
cannot be procured without coniiderable expense ; 
at the same time, however, a person may, with hut 
a trifling expenditi»re, make himself acquainted with 
all the chief facta of a science, snd even pursue it 
to a considerable eitcnt, with the aid of such appa- 
ratus as he may contrive, by a little ingenuity, or 
procure at hat little cost : this is peculiarly tbe caae 
with chemistry, which may be studied with little 
ex|>en9e, to a greater extent than perbapi any other 
science. 

The advantaget to be derived fr^m a thorough 
knowledge of chemistry, (which can only be no- 
qaired from experiment,) are very great, as well as 
every other hrnnrh «f s.rience as well as art, is more 
or less dependant on it. and many of them owe 
some of their chief facts to the chemical knowledge 
possessed by the di»C0Trrie« of them ; neTCrthelesa, 
chemistry it: fur less studied than Its Importance 
deserves, the generality of people either knowing 
nothing at all about it, or, at beat, resting in a mere 
theoretical knowledge of some of its prinoipid faeti, 
under an impression that It rcfpiires loo large aa 
outlay, to be follovcd by any but those whose pro- 
fession recjuires it. Thta idea is, perhaps, strength* 
ened by attending chemical lectures, where, as the 
lecturer generally makes a point of cjthibiring aa 
much apparatus as possible on his table, the unini- 
tiated are apt to snppase that oil this display of 
brass and mahogany b essentially necessary to the 
atndeut — than which, nothing can be more errone- 
ous. Another, and perhaps a chief cause why che- 
mistry it) not more atudied. la the extravagant price 
charged by the philosophical instrument makers, 
their charges acting, iu many coses, as a complete 
prohibition of the use of their instruments, to per- 
sons of hut limited means. 

The object of these papers Is to show to the 
young liow they may study chemistry with most 
profit to their parses, as well as to themselves. 
I do not profesa to advance anything new, but 
simply tn e]i|]]ain tha constniction and urc of such 
articles of apparatus as will supply the place of the 
more expensive ones usunlly figured and described 
in chemical works; many nf thrm are thr invention 
of persons whose names stand high in the annals of 
science, sud as all of them have been used, for a 
long time, and with success, by myself. I can con- 
scientiously recommend them. The use of cheap 
appnratns has at all times been supported by the 
example of the first philosophers. Dr. Priestley 
used, for several years, no other pneumatic-trougn 
than a small washing.tuh, and made some of hia 
motit bnltiant discoveries with it, and It is well 
known how economically Franklin proceeded, Of 
late years, much has been done with the prq/ienutt 
intention of benefiting the catue of science by tlie 
inln-iductiou of surae very pretty, French polialied, 
brass-bound, mahogany chests of apparatus, tests, 
^c, under the name of " portable laboratories,'* 
which, however, are, apparently, more for ornament 
than use ; if for use, it is decidedly the moet ex- 
jwiiaive plan of proceeding Uiat the studtiut can 



.GAZINE OF SCIENCE. 



Aua they conUln may be 
Mifonrxl) the price chari^ed 
V AIT lew in qoBDiity than 
for specimens ; thcr nre 
It would be reallj useful, 
wUlies Uf study with as 

of inttractiTe ezpfvi- 

tuftl routine or mntiipitla- 

roun^ studeut a fair Rlart, 

to proceed in acquiring 

|m« one of the most useful 

jjlle circlr. iht^rcby opeoiiig 

IliuKtible fiuurce of iostruc- 

bet will provp of in6iute 

iCvery-day transactions of 

(very path in life, gtvra its 

biority over those who are 

toqnired by the stadent are 
ii ipirit Imap ; 2. a Eanip 

tmakiag gases ; 2. pneu- 
; G. evaporating dishes; 
ii funnel ; 9. blowpipe. 
^ is a small lamp iuteiided 
if provided with a wick> 
Vnt loss of fuel by evspora- 
Qasks, evapornting dishes, 
nble heat, without smoke. 
be msy be made in the fbl- 
Uhort glRJU bottle that will 
W, and will stand steadily ; 
^'0( the neck, witli jiincers, 
lirith a tile, ur on a land- 
sound cork, or ^tituU bung, 
t middle of it, and fit it 
&c bottle, to which it may 
Old cut it olf level with the 
ii|) may be made cither of 
B of a phial, cut off with 
d fit closely over the cork. 
I plate, about 2 inches long, 
irith a rim or ledge ^ of an 
) which rests on the neck of 
tde enough to cover the top 
K from the flame. A larger 
Iced by pulling up or push- 
|f wick-holder. Wicks may 



in balls, about Gd. each ; 



pf wine, bat nsphthn will 
ply two- thirds of the price, 
^of a stroni; and disagree- 
trill be found equal to any 
9i cost more thaa 6d, 
to the spirit iamp, when a 
il is to Ix heated, is a tin 
^OTcr the lamp nnd shout 
jMfTcral arched openings cut 
jlr ; when the lamp is placed 
t^e steady, protects it from 
^ time causes s current of 
leirculflte round the bottom 
p vessel, thereby heating It 
than could be accomplished 

i 

0ed to "mpport vessels orcr 
Sowing will answer the pur- 
ttiiy cduhtructed: take three 
'. brass wire, each 1 H inches 
^Ibe figure of a squarestaple; 
together at the angles and 
B copper wire, so that the 



sides of eacb may (nrm a trtanicte, eacb side bebfg 

4 inches long, stan-'i"' nn Mif- i'— ^ '■>« !■ " mr-k-t 

lon^ ; when the ' 

atniid on the In ■■ 

twisting together the ends nf liirce sbart pin^«a iti 

wire, may be plsred on the lorire one ; in «»n!rf to 

apply n greater or le« drgrc^i of ' 

should be adjusted at different he'. 

vessel by means of pieces of wood <- 

nessrs, of which several should be ] 

3. Appara/uf for genertiiing go 'ni 
rc(|uire heat for their eitrication, 

Florence flAsks, which can be obi ■ 

roan's for \d. each; they must be .v *UJ 

pcarlssh and hot water previntts (o ; a 

glass tube passed through n cork, is r^ 

neck, tu conduct the t(as to the jais intei.< 

reception ; the tube should be atjtiut '^0 m--.. 

and \ of an inch wide, and shnuld 1>e brnt 

angle, about three inches from one enrt, by 

of the spirit lamp and blow pipe, u will he b 

explained. 

For making hydrogen, cnrbonic nrjd, 
gases, where heat is not required, noy ' 
a bent glass tube passed tlitough the coi»., -r .i i^ 
to the flask, will answer tbc purpose ; it ihi>uld atil 
hold less than four ounoe;*. 

4. A pntvmatic trough is • large t< 
with water, for collectiDg gufs, and prw . 
a perforated shelf to support the jar^ while 
a wiuh-h.-iDd bdsin will aii^wer the stndrnt^s pi 
Tery well: for a shelf, take a U ox. c 
a hole \ of en inch in diameter thr- 
with a large noil or nny Bocb lv/< > . >^<.vi., 
pincers, make an irrhed opening in the edge, 
} on inch wide and \ of an inch hiijh ; tb«M 
turea may be finished utT with a file ; thll 
inverted on the bottom of tlie basin, wlitcb 
with wnter, (he apparatus is ready for use. 

b, 6'iu Jan. — For collecting snd experxn 
with gases, 4 oz. phinis may be used ; a bo 
will hold half a pint or more, the bottorsr 
with a red-hot wire, is useful for many exp 
the phials will cost about 3^. each, and i 
chosen B» wide in the neck as possible. 

fi. Evaptiratiny ifiifhrx. — Vessels for tv 
are generally made of Wcdgewood ware, hat 
is expensive, and not absolutely nt-< 
experiments on cryittallixslion, Sec. 
u«F I'ominon gallipots, which he «im •>.>•> u; 
S9 vesiwls of ten times the price ; they msy 
of vtirious sizes at nbout Is. per dozen. 

7. Tcft glaatea, tx'c. — Vessels for testing, p 
tations, &c., may be replaced by wine gla 
tumblers : when a precipitate ts to be 
or champagne glossca are preferable 
their depth ; glass rods for stirring t 
be bad in moit towns, nt from Iff. to 
where they cannot be procured, n 
window-glass msy be used. 

8. A fflaJcM funnel, for filtering. &e. ; 
inches diameter will cost 6</. ; filtering 
sola at the druggists at 2r/. per sheet. 

9. A blow pipf. — This is a small ins 
used in coiijunctioa with the spirit lamp for 
on intense hcnt on a small m'Me : a common 
ing tube will answer the student's purpose 

This li^t includes nearly every thing re<|uir<d 

the Btndent ; a few misc^laneons articles, sudi 

dedagratiug spoons, &:c., will be described wbcrn 

come to the experiments in which they tre 

(n be cOHtinued.j 



MAGAZIN'E OF SCIKNCE. 



23 



THE EXPANSION OF ARCHES. 

aiuion of DoliJ*, which b«8 esrftotl Ihn 
of mnUtctciaticiLiiii since ttte inrestigatiuns 
ire, in t6t^8, qii a rod of iron, ik uf (lur- 
portanc« in Uic eonwtrurlioD of bridges, 
which majr be mtfecifA by the djlatu- 
ction conici^uent od change* of trtn. 
todic&l mottunA, rtferotilc oul^ to 
pemture, were observed by Vicat. in 
built o»cr the Dordogne, aiSouilUc, 
frequently b«ea ootit^fd in atructurea of all 
The ttiffL-rent cspinitibilitiea of stone aud 
t been coniidered an objecti»n to the use 
Iroa pilUr« id connection with stone, to 
the fronts of huildingit ; but the experi- 
' Mr. Adie, of Edinburgh, led him to tht- 
n th4C no danger is to be apprehended 
ibange of temperature affecting cut iron 
ne In any grrac degree, as their expan- 
Ikr N« rrgarda buildings, may be considered 
Ar){uu>enU from this source were em. 
piinat the archrij of Southwark-brid|;e. and 
tHtncnta act furth in this cominuiitcatiou 
icrtakco with a riew of aaccrtAioing the 
temperacure on these arches. Three sets 
menta were made, the 6rfttin January, 1318. 
Siain ribs and diagonal braces rcated on 
and before any of the spandrils and 
a had been put upon them ; the second in 
d Senietnbcr of the same year. The rise 
nircd by ihe injiertion of email wedges, by 
t rise was ascertained to about one-fortieth 
inch. The aioiit extensive set of expcri- 
Im made on the eaateru arch. Qreat care 
I in obserring the thermomctere, of which 
i ikret : one in the open air, another aroon^ 
«wl Uie third inserted in the iron of the 
It result of nine ciperiments gave, as a 
of one-fortieth part of an inch for T F. 
ti of changes uf teroprraturc were also 
la the stone bridge over the Thames, at 
^'V.r r|,.. arches had obtained their full 
.-■i were obaerved in the joints of 
iiately oter ihe spriugtni^ of the 
Bad a diatortioD, or sioking. of the uppn* 
the para|>ets. A wedge was inacrtcd into 
tiuwi opeoiogs, and the lowest point of its 
in the month of January, marked. The 
were carefully inserted CTcry week 
, wbcQ they would no longer enter, and 
me firmly closed. At tbia period, 
tots immediately over the crowns of 
b bad, doriag the winter, been quite 
opm. From these facts It follows, as a 
consequence, that iu winter the arch con- 
, and the spaudri] joints opened : 
tha arch expanding rose, and closed 
jind opened those at the crowns. 
of the parapets, which were made 
of granite for the whole height, 
od imiicatora of the change of tempera- 
hdd al»u been observed iu tlie Waterloo 
ca, that, joints made good in the 
an ccmwt, were found cmabed in 



LIQUOR FOR ACIDS AKD 

Ai.KAL1ES. 

ta of the Society of KrU hare been voted 
MsTkb, of the Royal Arsmnl, Woolwich. 



for his communication of the foUowiog new teat 
liquor for acids aud alkalies. 

The infusiDn of thit common red cabbage has 
Iwen long in um; in Ute chemical labomtory, aa a 
test to diiitinguish acid from alkaline bodies when In 
solution ; and, althouKh posiwssed of great delicacy 
in this respect, is still subject to au objcTtion, on 
nri-iiutii i)f its becoming so exceedingly ulfensive in 
it» smell, after baring bet-n prepared n ffw months. 

In order to obviate this objection, Mr. .Marsh 
undertook sdehc experiments, about two yenrs ai;u, 
on the coloring matter of the dark red hol]yht>ck, 
the purple radish, and the dark red beet>root; bat, 
during his experiments, he found many objectiona 
to all. The beautifdl blue color of the dark red 
hull) hock, obtained by alcohol, is, however, worthy 
of notice ; but Mr. Marsh's attention was forcibly 
drawn to the beautifully colored infusion obtained 
from the dark varieties of the dahlia, each aa the 
Conqueror of Sussex, Sir Edward Codriugtnn, Sir 
Edward Sugden. Alman's Splendissima, Parson's 
Rival, Brown^s Ion, Holmes's Rival. Sussex Lima. 
MetrofwUtan Perfection, Pasha of Egy]>t, Robert 
le Didble, and Sambo — these being the rarieties 
mostly employed. 

Thi« infusion is easily obtained as follows : — Into 
on infusion pot, or any common earthen vessel, let 
89 many of the petals of the above-named dahlias 
be lightly pressed, and then boiling hot distilled or 
good roio-wHCer, sufGcient to cover the petals about 
an inch, be introduced. T\\e best method of keep- 
leg them down is by means of a piece of pUte-glasv, 
or the foot of a broken tumbler, or even a piece of 
common porcelain will do very well. The whole 
may be kept on the hob of a common fire-place, 
simmering for two or three hours, covered over 
with a piece of common paiier, to keep out any dirt 
which otherwise might fall in. The liquor is then 
to be poured off the petals, whicli vrill be found 
almost colorless. To every pint of the infusion, 
add lialf an ounce of salpburic acid, keeping the 
whole slowly stirred with a slip of glass. When 
quite cold, add to every pint of Ihe mixtura two 
grains of corrosive sublimate disiolved in a portion 
of the liquor : filler the whole through a piece of 
coarse cloth, and bottle it up ; and it is immedtatelx 
tit for use. 

When wanted for use, the liquor is to be carefully 
neutralized by ammonia, which gives it a kind of 
olive color, and in this state it may he used liquid ; 
or bibulous paper may be dipped in it, and tiien 
dried. Either the liquor or the paper will become 
green with alkalies, and red with acids. 

Being desirous of turning to account some of the 
qualities of this class of flowera now so much coU 
tivatcd and so generally admired, and also render- 
ing them useful as well as ornamental, Mr. Marsh 
hns made several attempts to fix it na a dye-stuff on 
ctoths, &c. ; but has not yut succeeded in his 
attempts to his owq satisfaction. 

This test liquor has bc»n approved of and adopted 
at the Royal Military Academy and Royal Inatitu- 
tion. — ^Vansac/iorur iff the Society of Arts. 



MISCELLANEOUS EXPERIMENTS. 

Watch G/fl**e# — The art of making watch-glaasea 
depends npon the employment of caloric, as a power 
which expiindi gloss unequally. A glass globe is 
blown of sufficient sure to permit five glasiet beln; 



24 



MAGAZIXE OP SCFEXCE. 



cut from it. Whrn the globe is cold, a red-bot 
(obscco- pifw, or iron-wire, is nin roaod the 
model of the watcb-glnss drawu upon it ; Uie crack 
foIlow9 (he point of the heated wire or pipe, until 
tlie circle is described, and the watch-glus drops 
out of itfi place. The other four ore done in the 
lame way. This contrivance is admirable, consi- 
dering that it arose from wliat ii generally supposed 
to be a bad property of glass, viz. fracture by heat 
too Suddrtily applied. 

ffnbg/itufir Jar a Cnpying Machine. — Write with 
common vrittog ink in which lump sagar has been 
distotvrd, in the proportion of four scruples, or a 
drschm and a hnlf of sugar to one onucc of ink. 
Moisten copying paper, (a paper which is sold at 
the BfHtioner's for Is. lOrf. per quire, for the use of 
copying machines.) by paasing ■ wet soft bronh 
OTCr it, lUen press it gently brtween sofl cap paper, 
to as to arooothen it, and absorb the superabundant 
moisture. Put the pnper ao moistened upon the 
writing, and both between cap or other smooth soft 
paper, placing the whole on the carpet or hearth- 
rug, one end of whirh is to be falded over. By 
vtnnding and tresding upon this, an impression will 
be taken, equal, if not superior, to what would have 
been taken by a copying machine. 

TVaeinsf Deal. — Let a frame be made sufficiently 
Urge for ■ square of crown glass to rest upon it, 
BUpporteil by a ledge at the bottom |iArt ; where, 
by two hinges, it may be fastened to a drawer of 
the same dimensions, which may be dirided to serve 
for pnper, pencils, tec. To the top of the frame, 
fix two stays, by which the frame may be raised or 
depressed, as occasion may require. Thr fnune is 
to be used thns : — lay the subject you intend to 
copy on the glaf«, snd fasten a sheet of fine white 
paper upon it, with some wafers or paste. If you 
work in the day-time, place the back, after you have 
nised the frame to a proper height, agatnst the 
window ; but if by nigh^t put a lamp behind it, and 
you will see every line, which you muy copy accu- 
rately, and finish as you think proper. If it be a 
soUd piece you intend to copy, then filace it behind 
the desk, and having fastened your paper to the 
&ame, put the lamp so as to produce a strong ahade 
on tlie object you have before you to draw, and you 
will plainly see to trace the lines with a black lead 
pencil : aftrr which, fill up the shades in the manner 
it appears without the desk. 

Optical Ejrjierimentit. — .\ffix to a dark wall a 
round piece of paper, au inch or two in diameter ; 
and a little lower, at the diitauce of two feel on 
each vide, make two marki; then (dace yonrseJf 
directly opposite to the paper, and hold the end of 
your 6nger before your face in such a manner, that 
when the right eye is open, it shall conceal the mark 
on the left, and when the left eye is open, the murk 
on the right : If you then h'ok with both eyes^to 
the end of your finger, the paper, which is not at 
all concealed by it from either of your eyes, will 
nevertheless disappear. 

TtHy at the height of the eye, on a dark ground, 
m imall round piece of white paper, and a little 
lower, at the distance of two feet to the right, fix 
up another, of about three inches in diameter ; then 
pUcs yonrself opposite to tlie 6rst piece of paper, 
ud, having shut the Irft eve, retire backwards, 
keeping your eye still Axed on ibe first object ; 
when ;ou are at the diHtmce of nine or ten feet, 
the second will entirely disappear from your nght. 



A Simple Btavmtier. — Take n oommon 

bottle, and cut off the rim and p'"-' ■:■■* '' - 

This may be done by a piece of ■ 

whipcord, twtitcd round it, and pi: gl 

a sawing position by two persons ; one ot nliOB 

holdi tbe bottle firmly in his left hand. !f '-itc-J u 

a few minutes by the friction nf tb' thsn 

dipped auddeoly into cold water, i; 1) bv 

decapitated more easily than by n tns 

Let the phial be now ne<ariy filh maa 

pump-WBler, and» applying the fini, • "> 

turn it quickly upside down ; o j 

finger, it wilt be found that only • 

escape. Without cork or stopper of aii v 

water will be retained within the VmMH 

pressure of the eitcmal air ; th' 

without the phial bcmg to much i 

of the small ijuantity writliin it. >•<'» . 

lope be tied round the middle of the 

which the two ends of a firing may be ot' 

OS to form a loop to hang on a nail ; let it t>e \%m 

suspended, in a pcrprndiiMtlar msauRr, with (kt 
mouth downwards ; and thia ia the barcnmlv. 
Whrn the wvather ia fair, aad inclined to be aa> 

the water will be level with tlic seeii " * 

or rather elevated nbore it, and lu: 

surface. "When dtspotted to be wt 

appear at the mouth, which will enlonge t^ 

Olid then another drop, while the hnmi<lr. 

atmosphere continues. 

How to prepart Parthmtht Jhr Ptrinfin^. — IVIv 

about a yard and a half cf li«t, on* 

tight in a circular form -. then take ■■ 

dered white pumice-stone, put tlic 

rub it over the parchment. Tlii-> 

simple and very common, aimwers ' 

If you wi*h it to take water colnrw \^ 

choose tliat whit^ is not spongy an- i 

olum-WBter with tbe colors when you mis Utcni 

use. 

Ea$y Method of taking Imprtmona ftviu "." 

Cohtx, 4fc. — Boil B quantity of iainglas> 

brandy, or other spirit, tilt it is in a 

liquid state to pour upon the mrtoJ, &c 

may be mixed with this composttton ; 

be poured in a liquid itate to the mixtnral 

best to m\% the color with the spirit. 
Artijiciel Rain and Hail. — Makf: 

der of wood ; let it be very thin at ' •! 

eight or ten inches wide, and two or turcc iwi 

diameter. Divide its inside intu 5vc eqwd 

by boards of five or six inch^« ••■■'•' -•»■* i*' 

be between them and the wC" 

about one sixth of an inch. ^ 

boards ohUqncly. In this cylinder put fnur 

pounds of shot tluit will eustly pass through 

n|>eDing. When turned upside dn^i 

the shot going through the varion 

resemble rain ; and if you put lorgp in'jt. fi 

produire tbe ^ound of hail. 

To make n Ring tuapend by a THrtad, q^ 

Thread hnt b&en Awmeflf.— Soak a piece of tb 

rommun salt and water. Tie it to a rinc not 1 

than B wedding ring. When yon i> 

of a candle to it, it will burn to ashv 

tain the ring. 



Votit. I and 2 of this Magaxine are nov rvad^p^J 
tianiljf tivundin CJa/kandhtitfredtprictHt, 



LoMuON-^Prlnicil hy t>. thMHet*, S. Wlille Horse Urte. Mile Fwl - rgliliil.i.iJ hy W WaiTtAi*. H. l*atwi*^>Bt»v 



26 



MAGAZINE OF SCIENCE- 



raftftietic forre of this coftcnt opernting cm the 
compau* needle would Aefitet it out of iia Bintral 
direction ; and after a few oKtUationo ii would t^ke 
ft new atationary poaition. 'lltia new position ol the 
oerdle would not be at ri^t anglra lo ibe plane of 
the coil, became of ita etill bciog under tlte iti- 
Haenrt* of terrratrial raa^oftisru, b<i well as under 
the Killuencc of tbe flectro-mag^uf^tic force ; bni it 
%vould form on sngle with the meridian Uue of the 
oompass-csrd, the extent of which would depend 
■pon the extent nf the Utter force; or, if yoa pleaae, 
npotj tl)0 iiit< iisity of the electro .dynamic action, 
which krj't lilt: itLi'dle from reiomii^ to lia terres- 
trial hue of rcpOM;. 

If now we canbider ihmt the deetro-mag'netic 
fcrce ia ef(aAlly dUtributed orer every part oif the 
wire forming the coil, it ia obviotu, that by paaaing 
tbe wire once round the romposa-box. directly over 
and under the meridian line of the card, this forcv 
woald be brought into piny both on the upper and 
lower sidea of the needle : and theae two incre- 
meiiU uf force would conspire, and auatain tbe 
needle farther from the mcridum line thoB either of 
them aloDP would do. 

To fuiiiiltnrize the action which tends to the pro- 
duction o( tbia fact, Jet na suppose the circles to 
repreacut troiuvcrse aectioM of the upper and 

919 



tover portiona of the wire ; and thftt the aouree of 
electric action is a sinf^le pair of cop{ier and zinc 
platoa : then Hcctirdingly with what we have already 
shown, the rurreot would (lov/roni the end along 
the wire, (which imagine to he bent oTcr the farther 
edge of the conip8»s-box, behind the paper.) and 
return by the oth<-r end. This being undcriitood, 
the right lines with cross heads will show the diitri- 
hation of the polar line« of electro- magnetic force, 
due to the adranrtng and returning current. Hic 
north poles of the two )X)rtion& of those lines which 
are situated immediately between the upper and 
lower yarXs of the wire, will be observed to be di- 
rected towards the spectator's right, and all Uie 
mnit/i poles of those lines, towards his left. And 
M tlir needle N S ia placed between the upper uid 
lower iwrttoQs of tbe *ire. it is influenced, princi- 
pally, by those coimpiring furcea ; and is sustained 
out of \hp magnetic meridian by their joint action. 

In puraning this illastration, we mny now readily 
Imagine, that by passing the conducting wire once 
rouud the compnjs-box, the electro-maenetic action 
on tlie needle would be double that which would be 
due to either tbe opper or lower part of the coil 
alone. This being admitted, two such colls would 
be productive of (our tiniea the single lorce, and 
three eoUa would multiply the force six times, ond 
•0 on ; and hence the mime multiplier being given 
to this instrument. By this mciuis, nn ehwlric 
current. whoAc force in one strand of wire alone 
would be too freble to prndmie a perceptible motion 
of the magnetic needle, may easily he detcctird ; 
Mmetimrs by deflections of considerable extent. 

In^trtjid of employing ■ rompAss-box in the con- 
■tniction of a galranowiter, it ii now usnol to ouko 



fta open oblong coO of Uiin copper wire. previOMfy 
covered with sewing ailk, in ih" 't<-'>t>-.r it, .r t,..(inrt 
wire i* covired. This silker I'd 

as an msulator, to prrrent thr ■ -mm 

poaaing laterally from one cuu^^olutiuti tv kiiother. 
Tbe number of convolutions in each coil «aclea 
with the different viewa of the ronfrivrrs, from Can 
to more iboQ a hundred convolutiona. For gwamt 

purposes, perhaps about eightech or * *- "^*u» 

lnliona are qoite toffldent. The > «r« 

uatially packed cloae together, an>i ><^ 

Tertically on a board; and each extren'i 
wire frequently terminates with a small c>< 
purpoae of holding mercury, which ia : 
useful for connecting the instrument in lii 
or other electric circle. The r. 
shape the experimenter thiul 

long thin icwing needles, witJk .... , 

cut ofl*, answer as well aa any. One of tti 
magne^tized, may be sunpended in the cri' 
coil, by means of a silken fibre, wbii 
through an opening in the upper side, > 
fig. 3, or else supported on a pirot, a?> 
A deep groove is usually cut in the bat*' ' 
place the lower edge of the coil in, and a ^ 
card for measuring the angles of deflt 
pasted to the surface of the board over tlir ^ 

When the electric forces to be etamineii 
feeble, it will be better to employ two necdlea* 
their like poles in opposite directions, 
scnted in tig. 5. The advantages drrivrti t\ 
arrangement are, that wheu the nvedles are 
power, they will counteract each other's 
tendency, and obey the influence of an exci 
alight electric action : and in consequence 
positions, with regard to the coil, they ; 
orged in the same direction, by the 
electro- magnetic forces to which they ai 
The needleji may be inserted in any light 
OS a thin straw, a piece of dry gla»», r>r 
slip of card; and sustained by a silken ' 
tbt- figure. This is called the astatic rl< 
oouieter. Tbe angles of dcdectiuu ure n: -. 
veniently read off, when the graduated cardu 
on the upper aide of the coil, the dipper 
serving us the index. The astatic > 
vention of the late Italian philosopti> 
Leopold Nobili. 

As the electro -magnetic force is known to 
cline with an increase of dist"—- (• — 
dncting wire, auuther Importu 
in the construction of theae :< 
tended either for the detection, or tQe • 
ment of feeble eleiTtro -dynamic acliun. 
upper and lower Hides of the coil ah 
farther asunder than is necesaary for the 
of the needle between them ; and the up 
should be adjusted so as to move as clonic as 
to the coil. To prevent undulations of the 
disturbing the needles, the galvanometer a 
covered with a glaid shade. Although the ap 
galranuineter is nsually given to sit the 
forms of .Schwetgger's multiplier, mony of 
obviously very far from being deservinc; nf 
tied title ; and are of nu fxtthor u^ than 
iodicatinj^ tlie mere exiMtenry of an dL-ctrie 
Such instruments have ■ometiinecbeeu calh 
nobcopen. 

Dr. Ritchie's Torsion galvanometer, we 
not grueraily known, and as it posfeesaes 
culianties, a description of it will, no di 
interesting to many of oar readen. Tbe 



MAGAZINE OF SCIENCE. 



S7 



tiie Doctor'* own worcU^ «a wc find it in 

tmai n/ the Rttyni fiuMuiifm q^ -Oveal 

\Ji>r Ortnhrr IS30/' 

pnprr whtrti appcarrJ in thft firnt ]iirt nF the 

thiotU TranBACtinns for tH30,' I invejti- 

eJrtsticity of threaila of glt^s, and applied 

;y Co tlie ronntructian nf a ddirAte fral- 

Tbr instrument then desrrthed, thou^^h 

for moft pBr|>o»r«, reqaires «ooic mndi^- 

adapt it lu p^Tscnrcbea of f^itrtoio dclicacjr. 

»n of Ibe instrument, in it< more per- 

a few of it* namerous niiplicaliuntt 

ibject of this communirntion. 

^rirneiilal rcjiearches in rltvtrn-mD^ne- 

ettremcif useful to havr ronstantljr at 

of copper wire, of different degrees 

' Miith senlin^ wax. Tlie inost con- 

^ttf giving tbc wire thift coatinit; in the 

tch the wire between two itiipporta. 

\y, from one end to the other, with 

>irit lump, and continue rubbing the 

|Ui a etick of sealing-wax ; the wire 

»c coatin/;, auffirient to prcvetit me- 

rhen portions nf it are pressed to- 

mitruction of any piece uf electro- 

tus. 

v^re thus coated, beat it slightly to 

wax cracking, and form it into a 

shape, ronsiHting of lix. eight, ur ten 

of the wire, acci>rding to the delicacy of 

tent required. The upper «idc of the 

'Viuat then have the wires separated into 

' portion*, bent round a snial) cylinder, anil 

lued Htraight, so oa to kavn a circnlar 

the middle* about one-third of en inch 

The a»o of the circular ojiening in (he 

U to albw a BlendiT axis, carrying the 

lies, to fOMs through it, in order to ia> 

p<»iBvr of the iastrument, and render the 

needle aitatic. Portions of a brass Inbe, 

tnch looK, are to be soldered to the ends 

Firrt furmini; the rectangle, for the purpose 

a aniall quantity of mercury, to render 

contact complete. Fik*. G and B, ex- 

licel »C(<tion of the rectangle, and a hori- 

rtf ita upper side. 

ire» forming the rectangle are pressed close 
'-il by a waxed acwiog thread, 
tliem. The rectangle is then 
,r.r box, having the upper side 
idiDg panes of window gloss, for the 
ig up the needle from the agitation 
beh pane has a small semicircle cat 
of the edge, by means of a round file, 
a oircnlar opening directly above that 
\t. Venom rontrirances for suspend- 
ncedle might be adopted. The 
ipa the roost convenient : — Into a 
e or base, f\x two npright sop- 
feet long. A amall stage at the 
Ivided arcle on its opper side, end 
r eleratrd or depressed at plcainre» 
' frame of the instrument. The stage 
of the same stse as the supports, and 
distance, with two small screws pausing 
op|«»iite the centres of the open- 
)Ose of fixing the stage securely at 
A small cytindrieal wooden key 
a «man bore in the axis, for the pnr- 
iving the end of the glass thread, passes 
centre of the divided circle, end is 
«aail)t« without mncb frictioiL. 



'^Aftar numerous trial*, the following appf«rv to 
me the best moile of preparing tlie tliicnds of glass, 
so ef to bare tlirir extremities somewhat ihirk ead 
tapering', for the purpopc of sernring them iu tho 
Tnrvion key, and in the an is which carries the mag- 
netic needles. Take a *olid rod of glass, or a piece 
of a clean thermometer lube, having a fine bore, and 
draw out one of its ends as in fig 7. Direct the 
very )>oint nf the flame on the thick (lortinn, and 
pull it out, bKwrrn tbe two handjt, to the proper 
length and ftnencA$: nt the first trial, it wiU be found 
necessary to dr»w leveral, end select the one boat 
adapted to the parpoM. 

"Two slender darning needles, of the best sted, 
nrv then to he selected, the eyes to be broken off, 
and the ends tiled to a point elmilar to th« other 
endtf, und then strongly magnetized iu the usual 
way. 1'he needles are then to be fixed transveraelf 
in a piece of straw or other light sobsiance, about 
an inch lung, and at the dtfttance of alinnt bolf an 
inch from each other, with their corresponding 
poles in opposite directions ; — the one needle in- 
tended to be above the upper side of the rectangle^ 
and the other below il. One end of tbe gloss thread 
is then to be secoi-ely fixed in the end of the straw, 
or light axis, by means of strong cement or sealiog 
wax. wbihic the other extremity is fixed, in a like 
manner, in tUe centre of the Torsion key. A single 
fibre of silk, having a small weight attached to it^ 
is filed to tbe lower end of the axis, and made to 
pass through a small hole near the lower side nf the 
rectangle, for the purpobc of keeping the axis carry- 
ing the needles (n the centre of the circular opening 
in the coil. The upper needle has two pieces of 
fine straw, several inches long, fixed on its ends* 
BO that the slightest dctlcotion may be readily ob- 
serred. The extremity of one of the straws is 
made to oscillate between tw;o upright piecea of 
glass, to prevent the needle moving over un extensive 
arc. and thus lengthen the tinu necessary to com- 
plete un ubscrvution. The M-bulc will be obvions 
from the simple inspection of Ag. 4, in which A B 
is the rcrUngiilar coil of wire ; N S tbe magnetic 
needles; C the stage witb^be divided circle and 
Torsion key ; and G the glm thread. If instead 
of the glass thread tbe needle be susjiended by a 
single fibre of silk, tbe instrument beeoiura a gaU 
vanoscope of cxCronu delicacy. Tbe /oUowjng 
experiment aifords a strikiog illustration of the ex- 
treme sensibility of the instrument with this modi. 
flcocion : — File off a few grains from n piece of 
sine and cop)ier, by means of a coarse file ; place 
two «f these near each other, in the bottom of t 
clean watch glass, bring tbe clean ends of two fine 
copper wires, connected with the cups of the galva« 
nometer in contact with them, and then drop over 
them a small quantity of dilute acid, and the com- 
pound needle will be deflected several degrtcs. 

"The instrument by which 1 aaevrtaincd lin* esist* 
ence of a voltaic current from this elementary hnttrey, 
c-onsistrd of a greater number of coils in the rec- 
tangle, and tbe needlca were light acd stfongtjr 
majtnetixed." 

Gahanometera vstd *y Dr. Faraday —T^a gal- 
Tanometers, which have lieen employed in a great 
-variety of important eTprriments, are described aa 
below, in the rath and 205th articles of Or, Fare- 
-day's " Experimental Kosearcbca in Electricity." 
Phil. Trans, for 18.12. 

Article 78.— ** The Galvanomeler mm r«u«U)f 
made, yet sulSciently delicate in ita indicntuHia. 
Tiu! wire was td copper £orerfid «itii ailk^ azulj 



^8 



MAGA^HNE OF SCIENCE. 



ftUlMB ar eighteen ^oiivolutiuru. Two sewing 

nrriHiH \>frc luagrirttitnl Aud |i»»«vd tbrou^b > picCB 
• - parallel to each other, but in oppn. 

fi u'^, and about h«lf on inch tpsrt ; thU 

*y«tcm n^M fUfpentlcU by a fibre of urit^^mu talk, to 
thAt the luvrrr nrctlte flhAuIil be bctvi'ra tli£ eonro- 
li. ' ' ' ' ' , :iJi(l the uppt^r ahovf tbpm, 

'J :jo mcrtt powerful tuagncf. 

ku^. fc. .. - .,..,..... ■-. Lion to the whole. 

Articlti 205. — ** To ubtuixi perfectly BatiafM-tory 
results, ■ new galvanometer was convtructe^l, con- 
■ifdii^ of tvo independent colli, each cunuiniDg 
18 feet of ailkcd cop[>er wire. Thete cotU were ex- 
nc^Xj alike in sh!i[>c and number of turns, and were 
fuel &ide by Bide with a email iaterraJ between 
them, in wliick a double needle i-ouid be hune; by « 
filirc of iitik cxutly afl in the former iustrumt'nt. 
When cleotrical currents were Knt throoj;h them in 
the same direction they acted upon the needle with 
the aum of their power*, when in opposite direction 
with the ditferenee of thdr powera.*' 



CRYSTALLIZATION OP BISMOTB. 

BiBMrra tndti at 476", and if allowed to cool 
■lowly, it crygtalltzcfl in parallclopipcduns which 
jctin or rnther meet at a right angle and are enve> 
loprd in one auother lilie tlie turni of a volute, 
•ueh ao are trrmed MaGrecque, because the Greekt^ 
have often employed thii form iu areliitecture. In 
order to obtain this cryBtallisation, wc must wait till 
the bismuth is fixed at lUi surface ; then f>erforate 
the cru*t nnd pour off the fluid pordon, not in order 
to leave a space sufficient for the regular arrange- 
ment of the molecules as Rome de Lisle imagined, 
for the crTfltaU are formed in the midst of tfae liquid 
motiil like the saltA in their solutlan, bat in order 
to Iat hnre the crystals that are already formed, and 
not ititTer them to be inclosed in the whole of the 
fixed metil, M. Pongct haa actually obserrcd 
that when the solid crust formed at the surface of 
the fu*ed bismuth is taken away whilst the lower 
part is still liquid, tliis crust exhibits well-formed 
rryatals beniuth. Of i) the metals this cr^BLaUizca 
10 the most regnlsr and Msy manner. 

Dr. Reid ol>»cnfcf, " melt some bismuth In a 
crucible when the surfncc becomea aolid. and while 
the greater pNrt of the melal is still melted within, 
make a siiinlt hole in the middle and inrert the 
cruci*j!e til) all the liquid metal hss been poured 
out. On breaking iulo the hollow mass Oiat is left, 
tti internal surface will he foond studded with oryi- 
iala of luetaUic bismuth/' 




Another method U tn melt the hiamutli in on iron 
ladift, vwdlng the botWui by immersing it in culd 



«Bl«r before breaking tht Croat iborc, 
care put lo«ttow any water to toll apoa 
nietil, least some Of H should be throwa 
explosive viol«io«. 



PRIMING AND PREPARING CU 
THE ARTIST. 

PftOM the time that the restorBtion of 
Italy commenced, down to the dnya 
panclf were always lued for pninting 
when the works were to W fixed to i 
place. Canvasses nnited the Advsntagef 
new and easy removal. The latter, thrrej 
n preference ; and after Rsff'^ul's tic 
longer painted lai^ pictures on wood ii^ 

In the Low Countries Uie use of panel 
much longer. Even in the ttuiR of R] 
was, at Antwerp, a celebrated manufoc] 
the panels were prepared of ^re4t dim< 
after the death of the chief artist of t 
school, the artists painted osilj easel 
wood. 

The Italians preferred pojilar wood I 
pose. In Flnnders oak was used ; as iC 
dom injured by worms. 

It is natural to suppopc, that pnn^ 
of several pieces glued together, might 
uuitrd by the changes nristng from 
moisture, to which pictures are alw«] 
less subject. To prevent these occideota, 
care was taken in the earlier timea, 
these precautions were neglected \ b«n| 
were glued upon the joining, and even < 
they covered the entire surface of the 
black tanned leather; the gluring on of 
is Bttnljuti*d by Vicwaii to Marshtritun^ 
in tJie twelfth century, but it ws* knowi 
time, for the practice is described in * 
treatise, Dv arte Pingendh it was prol 
into Itoly by the Greeks. 

In the commencement of the art thft 
were prepared like the panels with 
grounds \ and generally the pictures of Pi 
were pninted upon such primed cloths. 

The practice now is, to prime the rli 
cobr, changing the mode aocordiug as 
is of a closer or more open texture. 
cauvBSs is very open, and lets the coU 
it must be saturated with siie mode of gU 
laid on with a Isrije pnlette knife or trow 
of which should be blunt, and as stralgl] 
thnt the couch of size may be lud 
pod&ible; when tltc priming is quit*' dry^ 
rubbed with pumice stone, to make it, 
lumps I then with the knife, a conch 
applied ; when dry this is obo pumi 
couch is then put on, and sometimet « 
Caia « perfectly even surface. 

ijjnncrly. the first priming was 
red. mlied with umber, or with pure 
some sixty years since, it was suppposn 
drying of this color wonld be quickened 
it with litharge ; hut it has been dii 
pictuiea painted on these aorta of prejiarl 
a few years have their surfaces covered wit" 
titude of little grains like sand ; and 
that the litharge was bctdly prepared. 

At the present day, the artists are 
in such cseeoLiai matters } and the 




MAGAZl?^ OF SCIENCE, 



29 



[lliar own ffiikn^ atr txrUte^ to prepare their con- 

«.-« tviiii tv.M^r ..tr.-Mti for any uruhijrfioe Lu 

1 rutii Chcir trade. 

.r tnring, ought to he of 

.itul nicHC evrii tcii'irp ; in this respect 

fwnuUarlv ad^untkijrouf ; for tLioueh at 

■ I to l>c faiitl of a much trreilcr width 

yul, if thp TnaTmfirNirerH foand h 

thcjr, Tio doubt, wontil nmke it up 

'- diuieiuions. If the cloth ia not 

juire three or four couches of color 

in eren nurfnfe ; »nd before « new couch 

' time mwit be allowed for the former to 

'i to be rubbed with pumice ; this it 

-loth requires, in prepanitiati, two 

>" in furnmer, iind t'lve or vlx io the 

lirrd for priming may be shortened 

..Aing the ftrst and second couches 

. and AS soon as they are quite dry, 

-a on eren surface, let the UaC couch 

iuch has become viscous by exposure 

will penetrate the distemper, and 

pliant. By the former method. 

•■ i jtr <> irquircd to dry the cloth. But by 

au>dr, OS ROon as the oil is absorbed, they mny 

n»llcil lilt liVu waxed doth?, with perfect safety. 

of these clothfl de)>rads upon tbe 

> of the oil with the diste^mper. the 

. would be greatly fncilitated by using a 

iiize, mixed with a little oil, and a good 

of BDuriln^e of limred meal, or the latter 

•loue will do if well boiled. 

..^.-i... .,f ground may be made in four or 

will economise tbe time consider. 

I rri-tendtrd that a picture may )>e 

ly unoo one of these grounds 

ff«^> -ltd that the colore will change 

IflK tliaii they do when used on a welUdried 

; but such is not the general opinion : for the 

oil lurd in the ground, and to which the 

rca its ptiaiicy, dricii but slowly. Hence the 

l.rinr left too long eiposctl to thc chcmlcal 

1, are likely to undergo a change. 

umstances compel artists to point 

lud when fresh, they woald do 

11 ' rtrong couch of white chalk with 

i!/r in It, to absorb the excess of oil; bat 

lu such a case, be still better to paint on 

groand. 



lid. 



tMPROX-ED PAPIER-MACUE. 

CLn has published a rery interesting 

oo the origin of papicr-mAchr, thc cauicA 

ovfiment, and its re-iutru<luctiua for the 

of tbe interior and exterior of booses, 

pplicstion of steam-power, and the rast 

nt. of recent date, in all branches of 

tlcasl >cimoe, bare enabled Mr. Bielefeld to 

• SBsterial similar, in name only, to tne 

" ' ' vi the last century : its biird com- 

rtrmctb. imperishable nature, ligbtnexx, 

'"tf, (if luch- an expression may be 

(iw (uality and quirkness with which it 

yvcparcd, pot together, and filed up. nnd, 

cheapitess, are qualities which emiuently 

iU bat which cannot, perhaps, be fully 

, rsc«ptiiig by those who hare had pro- 

ptrUucti in its application. Amuni; the 

architect, builder, and hou*c>dccorKtor, 



the most extensive opportunities are ofTi're*! fior tbe 
employment of Mr. Hielcfeld'i pnpier-inuchi> : Inos- 
much as not only all the forms of ornament com- 
monly in nse may be executed with it, in evrtry 
way superior to that with any other material, but 
its particuiur qualiciea are such as to e:it«!nd the 
field of inventiun immeasurably beyond (he limits 
to which it hab hitherto been confinrd. To assert 
tliat whatever hns been attempted in stucco may be 
■oeompUshed with the greatest fodlity in papier- 
mtLcbe, would be very inadequately expresalng its 
capabilities. Whatever the genius of Grinlin Giblrana 
IndoctM] him to attempt in wood, may be etfectively 
performed in papicr-milchc, with oo leM sharpnesSf 
DO less relief, no less lightness, and much less Ua- 
biGty to injury; papier-m&ch^ haWng this great 
advantaga orer wood, that, although as bard, it is 
tougher, and is wholly wiihoot the grain In wood. 
which gives it a bios or tendenry to chip ufT in one 
direction ; bnt with papier-iciich^ it is wholly dif- 
ferent ; no matter io what direction a blow faUs;« 
nothing but destructive violence will damage it. 

In arcliitccture and interior decoration, papier* 
mjichi' is advantageously used. Nothing can pos- 
sibly be more to thc purpose, in cases where an old, 
plain, plaster-ceiling, has to be rendered ornamental 
by the application of panels, jmteras, &c. ; without 
disturbing the ground of the ceiling, every kind of 
enrichment can thus be applied to the surface ; and 
so trifling is the weight of these ornamental addi- 
tions, that old laths and ceiIing>joists can receive 
tliem with perfect safety. A. new cornice, dry, and 
ready to color, can thus be fixed up against an old 
ceiling, without the delay, rubbish, snd dirt, attendant 
on running a plaster cornice ; indeed, without the 
removal of a aingle article of furniture, on old ceiling 
can, in a very few hours, be made, if desired, to 
asaume an entirely new aspect. By the Kama 
meanF, old pbiin stuccoed walls can be paneled, or 
otherwise enriched, with equnl convenience and 
deipatch. V\hen, from the Iaj»«e of lime, or other 
cause, the enrichments on an old atucrocd or can-ed 
ceiling have fnllen to pieces ; or when, ss is sot 
unfreqnently the case in works <rf even recent date, 
plaster ornaments have dersebed theroselres from 
the ceiling by merely the operation of their own 
weight j the injury is repaired in pspier-miVbe with 
perfe-ct success ; ornaments of great bnldnms and 
projection being thus applied to tbe face of the old 
work without the least risk, and when, peHiaps, the 
timbera ere so slight ss to make heavy plnsttr orna- 
ments highly dsngeroufl. In the completion and 
decoration of new bnildings is a further unlimited 
range of ornomentol ))arposes to which papier- 
m&chc is applicable (.'olumns of every order and 
degree of enrichment, including not only thc capi- 
tflls and bases, but the entire thafta. whetlier fluted 
in the claislc atyle, or fi-etted over with arabesques, 
ns in tbe C'inque-Ceato ood Eliiabethan styles ; 
caryatides, termini, and chimera ; are all produced 
with great facility snd bnt slight cost. 

Ceilings, especially, are wholly within the mas- 
tery of tbe manufacturer : those at the Pootheon, 
in Ojcford-street, snd Grocers* Hall, near the General 
Post Office, in London ; the vice-r^al state rooms 
of Dublin Castle, snd others, which may be referred 
to, display, in some roeasorc, what may be ftchieved 
in pspicr-miicb^ : yet these, superior as tbey ore 
in general effect, are specimens of bnt trivial sig- 
nificance in comparison with the powers and cajm- 
biiities of the material in the gorgeous details of the 
rasgnificCDt ceiJinge of tbe age of Louis Quaturxe, 



hM^ 



MAGAZINE OF SCIENCE, 



which cjm be fuUy and pcrmanentljr ei«mt«d ; and 
aft thtre U ntjibliihed endrnor of the diimliility ot 
|iftpier>iiuu-hr tn the 0|irn air,, it <tf courxr follnw*, 
that in all interior decorations its indratructible 
qoality may be still more tmpUciUy relied on. 

Pur jcaUcrj-fttmti, &lur-picccs, ur^un-ca^L-^, and 
othiT omamenUl parts of ctmntbea nihI rhiipels, 
pftpicr-niArh^ has now becomr fcnernllY minpt«d ; 
nor ia itA uso confined to thp.5« more inaportant 
work* ; many buDdreda of patvms or fluWRrs &re 
annually hand up on critiiigft of thf smaller class of 
jirivate dweULngs, in almunt every town of tb« king- 
dom. Flowcn are, further, cxtrnMVfly employed 
in covering the apertures for rentilution in tht eril- 
ingi of churchev, chapels, nnd places of public 
resort : piaster flnwi-rs hcinp only with much diffi* 
cully, and often timfs with danK:f^r, fixed up in these 
situations. Tbr wn-athn, or enrichrd baiuU. which 
/rcipirntly rncirclr these Howcrs, are also moat 
clfectiTely and elegantly formed of papier*rouch«. 
Another Tery usual mode of giving eohciuuent to 
roomi in the modem style, ia to connect with the 
cornice Home ^uilluche, or fret, upon the face of the 
ceding* and. where still more effect is retpnred, 
adding a frieze under tbe cornice, againut the face 
of tlic wail. Aa in funning Ihesc enrichments, the 
ground is firat finished plain, and the fohage in the 
papirr-mfiche then laid upon the face, it is olivioufl, 
to the prarticnl man, that a clear relief and distinct* 
ness of outline is tlierehy obtained : fjuite unattain- 
Hhl[! ill plaster work, where tlie enrichment ta cast 
wttlt the ground. 

Brncket^. consolec. and cantiltvers. in numerom 
and tasteful Tarietics. ore mode of this substance ; 
and indeed, one ol the earliest applications of 
Mr. Bielefeld's improved papier-mache to architec- 
tnml purposes, was the formation, on the accession 
of William the Fourth, of several large consoles and 
ooniioca. in the state apartments of St. James's 
Palaoe. Since that time, similar enrichments bare 
been supplied, by the manufacturer, to Groeera* 
Uoll ; King's College, Slnind ; tlie Carlton Club, 
aiui the Oiford and Cambridge Club Houses, in 
Pall Mall; tbe Briush Mnwum ; the State Rooms 
in Dublin Castle ; tbe Grand Mnsooic Lodge, Prce- 
inasons' Hall; the Corn Exchange; and other 
public buildings. 

Nor need its application ho limited to interior 
docoratiooa. At Paria. the Carton-Pierre, a suh- 
Btaucc analogous to pupier-mucht', but in every 
reapeot inferior, especially as rcgarda durability, 
being very abaorbeot of moisture, and, conse<iueiitly, 
liable to bacome aoft, is largely used for exterior 
ornaments, even in buildings of the most sumptuous 
and important character. Not oo tbe pnpier-muche 
of Eugliidi manufacture ; as even that uf the last 
century is found, on inspection, to atford abundant 
proofs of its extreme teoacily in exposed situations. 
The papier-mitcbe which enriched the fanciful nrchi- 
tcoture at tbe back of Sir William Chafflhera's 
house, in Berne rs Street. Oxford Street, now nearly 
three-fourths of a century old, is still in perfect 
condition. Mr. Bielefeld's improved papier^m&ob^ 
is of too recent introduction to afford a reference to 
any example of its adoption in txU'riop work beyond 
fourteen years ; but seventj sbop-rronls in the mc- 
tropulid, fitted up of that material, have at this hour 
their papter-miiche enrichmenta as sound, sharp, 
and perfect, aa when 6rst tuned out from the 
mould. 

Another and most important use to which the 
in\proved mdche may be applied, is that of render* 



ing ID duplicate forms tba emautioM of iW smlp- 

tor's skill : for whdst any piece of »*-iilitturr rifi *n 
insde ill ffkc-siuiilc wttli iwrfcet tiu 
is scorooly oue-slxth tbitt of pUsler, 
to injury or fraclur* i* in no way -rnl 

with copies or repetitions in eith« ' w, 

or woud ; Mliilst tiie economy of {>ii<><- pi;xc« (ha 
papier-m/iclu- ixprcimeiis bcvotid «U rrai-h of rlMlfy( 
as all being finished with equal mmuteni*«a and an, 
they have only to be colored in repreaentaboD af 
the marble origiiuli. 

Papier-miiche is applied by the cabtnet-mshaf 
and nphoUterrr, with surprising elTerl. to HV 
euncticd cornices of book*easea and caV>mpiai Iv 
the mouldings, comers, and centre arnauiriils a( 
paneling on their dnors and addes ; to the tiutuiuA 
scroll lega of rabinets. and pier tMl>ti<«. in thiiidd 
French style ; to ornamental brackrU fur cloekli 
busts, vases ; to the enriched borders of roonA 
hung with silk or paper ; the ornamental parts tt' 
picture and glass frames, however rurvtd nnd Ha« 
borate In their form ; and. also, to window-cart^ 
cornices, the canopies of bedstead*. &l-. 

With regard to the mode uf tixmi; papter-Mftdii^' 
ia cabinet work, the simplest and mc>»l mrrr..-' mU 
is. to treat it as if it were wood, and fa' 
means of brads, needle-points, or glue, t- 
cnt with a saw and chisel ; and may he U*At- b 
Rteam or beat, pinned, and rleanrd up with 
paper to lite smoothest face, and tn the An 
if required. The larg^ objects, such as bri 
and canopies, can l>r made ritber with a wood 
or wholly of papter-muche : in either case 
three screws secure them in their i.lti.-. 
fixed, the work can be painted an^l 
any previous prt^paration ; and, in :. 
face of the work is better adapted u> ; 
gold than that of any other material; mw 
expense and delay osually attendant on the p 
being tiicreliy saved. The aamc nhscrration 
to silvering; and, tt may be addr<> *)>- 
leaf continues untarniahed on pa; 
greater length at time than Ob other 
may be proved by the speclmeoi at C 
llotue. and other houses of the nobility.— 
Jirom the Literary Worlds vol. l&i. 

GLAZING EARTHENWARE AND CHI 
Thk glaze usually employed for common 
eartbeiiwarc is compounded of litharge of 
ground Hints, in the proportion of ten 
weight of tlte ibrmer to four parts of the 
Cornish granite is sometimes substituted for 
and used in the proportion of H pnr 
tharge. Tins method oi glazing i^ ' 
account of the injury which, notwi^ 
preeatitton that can be taken, it '.-■ 
apphc'Jitiuii, to tbe health of the worLj 
who freqnently are seised vrilh paralyaia; 
caose the lead, which is soluble by means of 
and higbly poisonous, renders vessel* thus 
improper for preparing or rootnintng Imman 

The mixturea just mentioned are called 
glazes : their employment is coovenieiit to the poU 
ter because of their cheapness and exlr-'-- '"■*- 
bility. Flint, which remains unafTccied in 
of the most powerful lens, is, when cont'. 
lead, melted nod vitrified at a cetnparativriy 
heat. The mixtiire mast be well stirred, thi 
powders may be always ke]it notformly hi 
throighoui tlie fluid. Tbe pieces are Arst bnuM 



1^^ 



MAGAZINK OF SCIENCE. 



31 



irm from dust, anil then mcrrty dipped 

^uiit Riid withtJniwn, when Ihey must be 

idly about in «lt dirrrlioii*. tli<t the ^Uxu 

qu&tl; over the whole siirfitcc. The su* 

quid h«%iiig hecn aUowrd to drnin off for 

da, and ihc pieces having bceu set oo u 

D^ A fvvr minatn, thry are ready for 

the for n are. 

Ill his '• Chemistry afiplied to the Arti/' 
a pniress for forming white enamel, 
ers well for gluing the tapenor kind»of 
and tender porcelain. Etpial parts of 
tin are kept in ftuioa until completely 
The powder thus fo^m^d ii ground with 
|inipnritic» Are removnl by repeated wash- 
being dried it is kept for use. The 
fa are then cho^pn, and fu«ed with car- 
ta^b, the latter being in »uch propor- 
flint, that the mixture will be soluble in 
the solution of flint thus made, muriatic 
from time to time, be added, until no 
pitation occurs. The precipitate thus 
pare silex, which buing washed and 
fit for um:. If then one part of this 
One part, of the metallic oxide, bo added 
of carbonate of potash, and the whole 
a crucible, the mass need only be re- 
fine powder to prepare it for use in 

m Rose, of the porcelain works at Coal- 
kropshire, apcaks in commendation of a 
ikrd porcelain which be baa used for some 
wbicV biTing been ex\mioed by compe- 
At tfae reqnest of the Society of Arts, 
rted on very favorably. Mr. Rose's 
mpoffcd of 27 parts of felspar, 18 of 
Lynn sand, 5 of nitre» 3 of sods, sod 5 
day of Cornwall. This miitore ia 
and ground to a fine powder ; 3 
oed borax being added previously to 

porrcinin and the finer kinds of earth- 
■n!!T made with white lead, ground 
|[|i lass, and comnioa salt; Lynn 

ll^ -oda.as a flux, being frequently 

' '-nti just mentioned. Almost 
|u li^ca a peculiar glaze, the recipe 

k Is ki:[>: iccrct by him as much as possible, 
I idea of )t3 superiority compared with that 
I by hi* competitors, so that it ts not pos- 
[glatti pruportioDS with accuracy. The 
pr.-viiiTi ni.ikers hare given the compo«i- 
kr ide by them, which are all said 

:■', groDod porcelain, and crys- 
gypsum, in the following diflerunC 

tin. I. Km, 2 Nrt. 3. 

. . . 8 pts. 17 pu. U pts. 
... 15 16 18 

tad gyp»um 9 7 12 

to vary the compofition uf tile 
Ibt to suit the diflcrent materials that 
ly of Che ware, since that would be a 
one mixture of earths, which 
1 propriaCe tx> Another, jiroving 
«., ^ ^..d being liable to crack. Before 
glaxtf in CDDJuuctioo with a particular 
, ic la most prudent to make trial of it 
aculcr in order to prove the suitable- 
bodies (0 each other, 
ia the competitiou among potters in tiie 
', tiiat meaoi which are injuriuus to their 



real quality are frequently adopted for mideriog 
their WBres leas costly. Some makers are hence 
tempted to the eniploymt-nt of nisteriuU that will 
enable them, at a moderate price, to furnish arlirlM 
oppanrnlly good, but wliich will apeedily prove de- 
fective when brought into one. The saving which 
the manufacturer i^ able to effect, through ibo adop- 
tiou uf an inferior glaze, consists uutso much in the 
■ctunl cost of its component parts, an. in the smaller 
quantity of fuel required fur its viiriAcatioa. and ia 
the shorter period of time demauded for its coo- 
veraion. 

The earthenwares ofiered, at low prices, by hawk* 
eri and pedlers, and at inferior shops, arc mostly 
composed of clay that will not bear a proper degree 
of heat in the oven, and arc covered by a gloso so 
tender oa to craze after a few cleansings with hot 
water. If exposed to a high temperature, or if 
acids be applied, the glaxe will be dissolved, and Uie 
vessels conftequrntly rendered useless. The quantity 
uf lead which enters into the compooilion of the 
better kinds of glaxes is so small, that the deterio- 
rating and pernicious effects which attend upon Ihc 
usv of raw glaze need not be apprehended from 
their employment. 

Ai alkaline substances are so powerfully instru* 
mental in promoting the fiiaion of intractable bodies, 
it may he thought, that by increasing their pro- 
portion when combineil with felspar, gloiva might 
be formed that would fuse at a beat sufficiently 
moderate for any description of earthenware, and 
that, consequently, the use of oxide of lead, which 
is so pernicious, might be altogether abandoned : 
bat onother serious evil which would then be ex- 
perienced prevents this substitution. The glaze, If 
it contained bejrond a certain portion of alkali, 
would not undergo the same tlegree of expsn^ioa 
by heat as the body wbcreon It is laid, and would, 
as a conaequence, crack to such a degree as, when 
brought into use, would allow any greasy matter Co 
penetrate through to the body of the wore ; and 
this would speedily destroy its coherency. 

The qnalilies which it is the object of the manu- 
facturer to give to porcelain of the finest description, 
are density, wliiteness, trmnsparenoy, and fine tex- 
ture of the glaxe. These properties are estimated 
in the order wherein tliey arc here enomcrntcd, 
compactness of body being the point which it is con- 
sidered most desirable to attain. The glaze, as scoq 
in the finished porcelain, should not put on a lus- 
trous appearance ; hut while beautifully smooth to 
the touch, should present to the eye rather the soft- 
ness of Tclvot tlum the gloss ot satin. This pecu- 
liar semblance will only be produced wiili glaxe 
tliat melts with difhculty, and when the hoat has 
been raised preoisely to, and not beyond, the point 
that is necessary for its fusion. 

The glazing: of common red ware is effected by 
the decomiwsiliou of common salt thrown into the 
kiln, at or near thi* conclusion of the baking procre«. 
Other gUzea o^ likewise employed for many orti- 
cka, and, acconliug to the usual system, the par- 
ticular oomponenta of the^se arc abo veiled in 
mystery ; groond glass is, however, understoo<l to 
be the basis of all. 

The diiferent colora observable on the outer aur- 
face of drinking jugs and other articles, is owing to 
the partial use of a ftlaze, the part to which this 
is appUed becoming dark in the heat of the kiln. 
while the gloxing of the light colored portion is 
cauaed by the introdaoUon of salt. 



mmk 



39 



MAGAZTNB OF 



NOTBS ON THB 



'^^^^ ter;:2,rKr.i;;3:f' 



RatsBaaoji. 

Dnuii . . . . 



Me I 



30-02 
WS85 
SO -061 






0794 
1&I3 



Ts thii mnnth BntmaU of alt kindi are in full vigour. 
Tbe bcASlB enjof dieroselvej in the fresh pastures. 
The grovci resound with the loni;! of the feathered 
race. The reptiles and donnant animali, as Che 
acaaon progrewea, and the air becomes warmer, 
break trota their winter'^ torpidity. Trees and 
pools swarm with inncct life Ptsh again become 
active, and fill the stre-ams with tlieir spawn. Trees 
bioftftom, vegetation rapidly proceeds, flowers enamel 
the meads and hedge-rows, and all nature seems to 
smile, Mun finds his spirits improve, his vigour 
increase ; his ogrti^ultural labours occupy his at- 
tention, and he returns to them with renewed 
atteutiuQ and xest, urged on by the united stimu- 
lants of health, proAt, and pleasure. 

ANIMATED NATURE. 

Lererets and young Rabbits are now first seen 
gamboling in the copses and among tbe young crops 
in the fields. 7*he Cnckoa is heard early in the 
month. The Chimney Swallow, tbe Swift, the 
Martin or Mortict, and others of the Swallow tribe 
rtttnm to us again. The Corn Crake and the 
Nigbt Jar make their discordant noieea. The Tic- 
lark sings. The Goldhuch. the Blackbird, nnd the 
TliriLih make the groves re-echo with their varied 
melody, and towards the end of the mouth the 
Nightingale may be heard in the forest. The Dove 
and PtJgeon coo, the Redbreast, the Willow Wren, 
the White Throat, the GrasNhniiper Lark, and the 
Goatsucker return from olhiT climiia, to spend their 
summer with us, and towards the end of the month 
the Great Bat flutters in tbe evening. Reptiles, 
the Frog, Snake, Eft, and Lizard ore, if the weather 
be warm, tempted from their winter quarters, and 
lay their slimy spawn, tbe first in ponds, the rest 
mider dunghills or warm walla. 

Fish sport up and down the streams, and find 
abundance of food in the larvie of numerous in- 
sects nnd worms, and shelter for their spawn amidst 
the young and growing wuter-planLa. Snails and 
Slugs Appear in the gardens. Earth-worms are 
abundant. The Cockchafer or Mayfly abounds on 
tbe trees. Tlie Lihelhilnr or Dragonflies sail over 
the pools. The Ladybird, or Ladycow, the Green 
Aphis, and the White-cabbage Butterfly are of con- 
stant recurrence in the gardens. 

VEGETAULK Llflt. 

In the fields, the Botanist will see many of bis 
Isvorites appearing again, while those of winter 
an not yet over. The Mosses are still in perfection ; 
indeed for most of them this is the best season. 
Tbe Brynma ore now particularly fine ; so are Che 
Gymnostomums, tbe Tortulas, the Poljtricbums, 
and the Fhoscums. AlgB are nSfr in vigorous 
growth, but not yet fertile. Lichens ore decaying, 
or rather becoming dormant till the damps of the fol- 
lowing autumn shall agoin urge their farther growth. 
Fungi also are nu lunger abunuant, though many of 
the Polypori arc yet to be found, and indeed mime* 
roofl otbm on decaying plants in damp situations. 
Flowering plauLi arr leeu every day to put forth 
frc^h blo^tiomi, though it is not till the end of the 
moiiLh that ihc rciU ht'auly of surouicr is fully esta- 
bliahcil. In the tarlicr part of the month VMrious 



MONTR OF MAY. 

of the Dead Nettles, tbe PHcwovt, T'- '^' 
Palustrijt, the Daisy, the D«ndHio«, il 
Ivy, vorioua of ihe early Spfcdwellt. i 
thorn, and tbe Shephrrd's Vursc, vc almost 
only common plants. Towards the lattrr port 
the month, the collection is greatly increased 
in number and in besnty. The trees are in 
greatest perfection. Tbe Sycamore and Maple 
Chestnut, the Hawthorn, (emphatically calli-d tl»e 
May,) tbe great tribe of the Willows, [the Fi 
the Pine, and Fir, the Poplar, the Borberiri 
Iris or Cora Flag, the Ijly of tbe Vallfy, the 
Rose, the Columbine, the Buttercup, the Plaintlfa^ 
the Wallflower, the FOTget-mc-nol, the W 
Violet, Milkwort, and numerous others, f^ome 
these, though indigenous in our islandt, are broMgbt 
into our gardc'Df, where they flourish, yet not with 
greater beauty than in their native wilds. Th^ 
garden at this season is still in its infenry, yrt 
begins to put on its summer dress. The liur^ 
Ancmonles, Ranunculus, Anricolas, and the Pbly- 
anthna tribe ore now in i>erfec(ion. Peouies, the 
Crown Imperial, the Tulip, the JooqaU, and nume- 
rous other bnlbs. are in full flower, and aided tiy 
tbe Aisles, tbe Fruit Trees, the Early Heaths. lh« 
Ilorse-chesnut, the Tulip Tree, the Drabs, andthf 
Aubletia. and other no less beautiful trees Moi 
plants, make the garden gay long before its seed* 
lings and the majority of its herbaceona pliats ibov 
any signs of beauty. 

OAKDENINa OPCIlATIONfi FOR TBS UONTI. 

Pruning and Transplanting of Trees and &bnbi 
is now over for the season, and the gooenl Sunour 
Crops are sowed and planted ; the digging up of 
the borders Is completed, yet much rematn» tor 
the gardener to attend to. Weeds at all timu srt 
to be eradicated ; and if frosts prevail, as they 
do in tbe early part of the month, the y 
tender Radishes nnd Lettuces must be diftn 
strow or other matting. Sewing and I 
Culinary Vcgctabli?s is still to be contiQu> 
vols to obtain a succession of crops. Sow ar mM- 
vols of a fortmght. Spinach, Radishes, Small Sabri, 
Peas, and Besus ; Carrots for Ute drawing; Bors- 
cole. Dwarf Kidm-y Beans for a main crop, CsoK^ 
flowers. Onions, Savoys. Stc., may still be soind> 
Strawberries transplanted. Their numers must te 
nipped off, and the suckers of all trees and b 
except Raspberries, rooted up. Sow Ci| 
and Tomatos on warm borders ; and 
Melons, Cucumbers, Stc in the frames. 

In the Flower Department of tbe gvden» 
of the more hardy Annuals and Biennials 
have been sowed under glasses, may be 
planted — such os Ten-week Stocks, Chitin 
TobacoD, flfc. ; snd tbe sowing of the yn< 
of border flowers be continued for a st,. 
crops daring the summer, such as M 
Virginia Stock, Indian Pink, Poppies, Coot 
and others. Such bulbuua snd tubprooa 
still remain out of the grounds must b« pi 
early as possible, such as Dahlia, C »mrnf'll 
In the Nursery Grounds, tbe &l 
should be sowed— of Wallflowers, • 
Rocket, various Stocks, &c., and uuutciuusof 
Potherbs, and Flowering Plants and Shnib^ ma; 
propagated by cutting or parting tJie roota. 
young plants now springing up will require 
ing If the weather be dry, and the corlli 
luoBtned. 



■t^. 



about' 



LtfSMOf ^PiialcU by D. rsAjccu, fi, Wbtta HurM Laue, AlUe £ad.— t*at>Ii»be<l by W. BsinAin, 11. Paicroottrx Koc, 



i^ 



rik 



34 



MAGAZINE OF SCIENCE. 



DORPAT TELESCOPE. 

Toe late Joseph Fmunhofer, of Munich, b most 
akilful artist Bnd eipcrimenter in optics (whose de- 
anise in I82C, in tbt: prime of life, was a great Inss 
to science), construrted a tna^jtiificcnt refrartiog^ 
telescope for the obsen'ocorr of the Impriial Uiii- 
vrrvitj at Dorpat. It warn rccrivctl by Prufe»or 
Strtivp, in the Tear lH2a, and has Mnoe been found 
to fulfil mont Autisfactorily hi* expectation and the 
intentions of the maker. A* this is one of the most 
mn^iiticcut iDstrumenlsof the kind that has hither, 
to been conktructed, and described by a figure, we 
hsvi^ given an engraving of it. copied from U&e ** Me- 
moir of the AslronoDiical Society.*' 

The (thjtN't-glass of this telescope is about 9J 
inches in diainetCT, and its focal length about 14 
English fei;t. The main lube is 13-H feet ; and, in 
addition, there is the smatl tube which holds the 
eyepieces. Of these there are four ; the least 
itiafrnifying power is 175, and the greatest 700. 
JUter the telescope was receiTed at Dorpat, a per- 
fect micruraetrieal appaniiaa was ordered to be 
made for it. This was to consiit of fonr annular 
micrometers, of which two were to be double ; a 
Ump circnUir micronieter, with four eye-pieces; a 
refracting lamp net micrometer^ with po&itioa ^cir- 
cles, and fnureye-pircea. 

Tbn frame-work of the stand la made of oak, and 
the tube of deal, Tcneered with mahogany. The 
wholu weight of the telewope and iu coanierpoises 
jpi sup}>ortvd at one point, namely, at the common 
centre of gravity of all th« poiideroaa parts. Tliesc 
weigh 300U Russian pounds, of which the frame- 
vrork contains 1000 ; the rcmainmg 'iOOO are so 
balanced in every position, that the telescope may 
be turned, with rapidity and certainty, in CDCry di- 
rection towards the heavens. 

The basis of the frame is formed of two ctom 
benma, each 9 feet 7 inches long. The ends of 
these are seen in the figure at A, B, C, D. They 
are braced by four smoUer bars, farming a square, 
one of which i» seen at E. This braced cvosb is 
fastened to the floor by eight screws, 6 of which 
are teen in the figure. A perpendicular popt, about 
6 feet high, and 7 inches square, is fixed over 
the centre nf the cross, and is propped at the north, 
east, BTtd west sides by three curved stsy^, denoted 
by O, ti, G, whii-Ii arc fixed at their lower ends 
tu tilt bcsma of the cross, and at the upper to the 
verticiil |K>st. An iurlincd beam H of the snme 
thickness rests on the southern side of the meridian 
fieam of the croas, and is alLsched to the Tcrtical 
beam in a position panillel to the polar axis, lliis 
uto, shown in the figure at I. is ■ cyliniler of steel, 
30 inches long, and ]>raportiona1ly thick. It turns 
In two colltrs, and itn lower end, which is rounded 
and poliithed, revts uu a Mtcel plate attached to the 
bearing piece K, which is secured to the inclined 
beam H, and has. therefore, very little friction, the 
wt-ight being supported by friutioa rollers near the 
common centre of grarity ; and a coanterpotsc L is 
applied, to support the axis in any position. There 
is a circle, 1.1 inches in diameter, graduated tii mi- 
nuu8 of time, fixed to the lower end of the axis, 
niid tiirnishrd with vcmiers. The axis of vertical 
iiv-tlon of the telescope, which baa nearly the di* 
ni< iiMons of the polar asi£, paasea throogb a brass 
ti.li' III right aneleft tu the latter ; the tube, which 
j^ i-^-'-n ut M, forms n part of the frame, and is fas- 
tened at the upper end of the polar axis by twcWe 
•crews. This Axii L&rrics the L-irclc of decliDAtion, 



which is 19 inches in diitmctci. and ii dh 
every 10', with a vemier rruiling 10" o( 
estimation. The tube of the telescope ia ! 
the frame-work nearer to the eye end ibaad 
die, and has two connteriioisea attacbed to 
which balance the tn'o ends, and prevent th« 
tendency of the longer end to bend. TH 
frame holding the two axes appear* on tbi 
clomped to the tube by two strong ring*, 
each end of the centre of motion. A bcu 
carrying the weight O, embraces, by a douh 
the near end ot the axis of the declinalioi 
The axis itself carries another weight j and 
and the weight O It ta coanternoised. T 
motion in altitude it given to the leIeaco| 
joint applied to the screw of the clamp, wll 
a spring urging it against a atrcmg iron bu 
uchcd to the end oif a cylinder M, that 1 
stop to the circle ; and a slow equatorial nu 
given by a aecond joint taking hold of aa 
screw, acting with tbe racked tdgit of th* h 
cle, while a spring pressea it into actktt wM 
and a lever ia ctnployed to ralac it out of d 
when necessary. Tbe bandies UUng hoU ( 
screws extend to tbe reach of the obaervflr. 1 
thus point hia telisacope in rifcht aaccnsioo j 
clioatiun with the same certainty aa the ba 
dian instrunwnt. 

A regular sidereal motion ia communiflatw 
instrument by clock-work, which kcepa a i 
parently at rest in the centre of the 6eld d 
and there ia a contrivance by which the \ 
can be changed into a solar, oIm Io a lOMT 
motion. 

This almost invaluable instrument coct 
flonns (about 950 ponnda sterhng). Tlu 
altbongh it may appear coostdersbic, yei 
covered the cxpensea of the workmuishi]! 
constrnctian. This relinqoishmeut of the y 
trade difia great credit to tbe ingenioua and 
minded artiata, PrannhoCer, and Utzcbneid 
chief of the optical establishment at Munich. 



THE TIDES. 

One of the most immediate and remarkaUl 
of a gmvilating force external to the earthl 
alteruate rhc and fall of the surCscs of < 
twice in the conrve of a lunar daj, or ti 
50 minutes. 28 araoods of mean aolar (uac 
depends upon the aetioD of the san anS oux 
classed among astronomical problems, of i 
is by far tbe most difficult, and iUi explanal 
leoMl antisfactory. Tbe form of tbe sur&OM 
ocean in etiuilibrio, when revolving with tfa 
round its axis, t3 an elUpsoid flattened at fbl 
but the action of tlie sun am) moon, fcpo) 
the moon, disturbs the eqnilibrinm of ibe 
If tlie moon attroctcd the centre of gravit] 
earth and all its particles with equal and 
forces, the whole system of the earth and lb« 
that cover it, wonld yield to these forcn 
common motion, and the eqoiUbriam of tl 
would remain undisturbed. The difTcrvnai 
forces, and tbe inequality of thetr direcuou 
distnrb tbe equilibrium. 

It ia proved by daily axperience, as «iil 
strict mathematical reasoning, that if a nw 
waves or oscillations be excited in a flidll 
fbrcnt forces, eadi parsnea its eoum, md 
effect independently of tbe rest. Now, ia t 
there are three kimi& of oscillations, tlcp«all 



MAGAZINE OF SCIENCE. 



35 



Uid prodaclni; tbeir ttCuctt inile- 
-t> other, which may therefore be 



I of the first kinti, which arr very 
r itiiiciii-n<lcDt of the fetation of the earth ; 
fT ilrpenil upon the motioa of the iltsturb- 
m its orbit, thej are of long periods. 
md kind of OHcUtations depends upon the 
of the earth; therefore thrir luiriud is 
day. The osciltations of the third kind 
■n an^e equal to twice the angular rota- 
be earth, and confequentlj happen twice in 
brar hoam. The tint afford no particuiar 
ind arr ritremcly Kinall ; but the difference 
inierutive tides dependi upon tbe second. 
ne of the solstices, this differcnci', which 
be very greitt, necarJtn^ to Newton's 
hardly lensible on our &hore«. La Place 
n thai the diEvcrepaiicy arises from the 
the aea ; and tliat if the depth were ooi- 
rv would be no difTercncc in the conaecu- 
bat that which is occatiioned by local ctr- 
K9. It follows, therefore, that a« this dif. 
eitremely fmail, the sea, considered in a 
■t, mnat be nearly of uniform depth ; Uint 
•here is a O-Ttain tnran depth from which 
|)oo it not preat. The mean depth of the 
Icean is supposed to be about fuiir mites, 
be Atlantic only tlirec, which, however, it 
Evrtarc. From the formiilte which deter- 
difference of the consecative tides, it ia 
hat the precession of tho equinoxes, and 
ft of the earth's axis, arv the same as if 
rmrd one solid mass with the earth, 
ftions of the third Idnd are the scniidiurnal 
vmarkable on our coasts. Tbey are ocr«- 
the combined action of tlie sun and monn ; 
affect of each is independent of the other, 
' be considered separately, 
jrtides of water under the moon are more 
Plhen the centre of gravity of the earth, in 
ffae ratio of the square of the di<)tauces. 
ey have a tendency to leave the earth, but 
fed by their gravitation, which is diminished 
lendenry. On the contrary, tlw monn 
he centrt of the earth more powerfully 
Ittracta the particles of water in the hcmi- 
Iposite to her ; so that the earth has a 
to IrsTfl the waters, but is retAined by 
I, which is again diminished ty this ten- 
Thos the waters irnracdinlely under the 
drawn from the earth at the same time 
krth ia drawm from those which are dia- 
'opposite to her; in both instances pro- 
elevation of the ocean of nearly the same 
ive the surface of ec|uil)brinm ; for, the 
I of the gravitation of the particles in each 
almost the same, on account of tlir dii- 
te moon bring great in comparison of the 
n earth ■ Were the earth entirely covered 
I, the water thus attracted by the moon 
the form of an oblong spheroid. 
Ktrr ni« would point townrds thu moon, 
f :" water under the mocn and in 

It ncally op|rosile to her, are ren- 

Mitrr It] ( Liiikequence uf the diminution of 
fixation ; and in order to preserve the equi> 
axr» 9<>' distant would be shortened. 
Ion, on account of the smaller spoce to 
confined, is twice as great a«i the 
because the conti-nis of the eplieroid 
the aame. IT ihc sralcra were capa- 




ble of tmuraing the form of equilibrium inslantane- 
ously, timt is, thn form of the •tpheroiri. tU Fumroit 
would always point to tlie moon, notmthitnhding 
the eaiih'f rotntion. Itnt uti account uf their re* 
sistanoe, the rapid motion produced in them by 
rutatton, prevents them from assuming, at every 
inntant, tlie form which the eqailibriura of the 
forces nrring upon them requires. Henee. nn 
account of the inertia of the wilers, if tbe tides he 
considered relatively to tbn whole earth, and open 
tea, there is a meridian attout 3U^ eastward of the 
moon, where it is alwuys high water both in tbe 
hemisphert! where the moon is, and in thut which 
is opposite. On the west side of this circle the tide 
is flowing, on the east it is ebbing, and on every 
part of the meridian at 90'* distant, it is low water. 
7*his great wsvc, which follows all the motions of 
the moon as far as the rotation of the earth wiU 
perihit. Is moditlcd by tbe action of the sun. the 
cfiVctK of whoae attraction arc in every respect like 
those produced by the moon, though greatly leas in 
degree. Consequently, a similar wave, but much 
smaller, nused by the «un, tends to follow hia 
motions, wliich at times combines with the lunar 
wave, and at others opposes it, according to tbe 
relative iwsitions of tbe two Inniinnnes ; but ns tbe 
lunar wave la only moJilied a little by the solar, tbe 
tidra must uecessority hiip)>eo twice in a day, itnce 
the rotation of the earth brings the same poiut 
twice under tbe meridian of the nwon ia that time, 
once under the saperior, and once under the inferior, 
meridian. 

In the semidiurnal tides there are two phenomena 
particularly to he diatinguifilK-d, one occurring twice 
in n montli. and the other twricc in a year. 

The first phenomenon is, that the tidca are much 
increased in tbe syzlgics, or at the time of new and 
full moon. In both cases the sun and moon are in 
tbe same meridian ; for when the moon it new, tliey 
are in conjancUon. and when she is full, lliey arc 
in opposition. Jo each of these pabitiouK, their 
action is combined to produce the highrst or spring 
tides under that meridian, and the lowest in those 
poinU that are 90" disUut. It is observed that the 
higher the sea rises in full tide, the lower it ia In 
the ebb. The nei^ tides take plaec when the moon 
is in quadrature ; tliey neither rise so high nor sink 
so loiv OS the spring tides. Tho spring tides are 
much increased when the moon is in jterigc*:, becausB 
she is then nearest to the earth. It is evid<*nt that 
tbe spring tides most hippen twice in a monrh, bince 
in that time the moon is once new and onre fiUl. 

The second phenomenon in the tides is the aug- 
mentation, which occurs at the time of the rqni- 
noxes, when the aun's declination is zero, whii'h 
happens twice every year. Tbe greatest liden take 
place when a full or new moon buppens neur (he 
equinoxes while the moon is in perigee, The in- 
clinRtion of the moon's orbit to tlk; eHiptie is 
y 8' i7"'9 ; hence, iti the equinoxes, the action of 
the moon would be increased if her node were to 
coincide with her jMiigree. For it is clear, tlial the 
arlioii uf the sun oitd moon on the occmn ia nio*t 
direct and intense whrn they arc in the plnnr of 
the equator, and in the i>ame meridian, iiud when 
the moon in conjunction or opposition is at iwr least 
distanre from the earth. The spring tides which 
happen nuder all tbcve favourable circumstances 
mTwt be greaU»t posuible. The eiiBiftoctiaJ gales 
often raise them to a great height. Bosides these 
remavkablc variatiuns, there arc others arisi/ig from 
the dodinjLlion or angular distance of the sun tod 



AA 



zn 



MAGAZINE OP SCIENCE. 



moon from the plane of the equator, which have s 
grent influc-nce on the ebb and flow of the waters. 
The iun and moon are continoalty making the 
circuit of the heavens at ditTerentdtRtances from Che 
plana of the equator, on arcuunt of the oMiqutty of 
the ecliptic, and the inclination of the lonar orbit, 
'flic moon takes about twenty •nine dayi and a half 
to vary through all her declinations, wfairh some- 
time)) extend 28f degreee on each side of the oqiia.- 
tor, while the sun requirei nearly 365} days to ae* 
com^lish hia motion from tropic to tropic through 
abo^it 23^ degrees ; so that their combloed rootitm 
rau«e« grent irregalaritiesT and, at times, their 
attractive forces connteraoc each other's effects to a 
certain exCeut ; but, on an average, the mean 
aoonthly range of the moon's declination is nearly 
tha same as the annual range of the declination of 
the SOD : coDsequently, the highest tides take place 
sfithin the tropics, and the lowest towards the poles. 
Both the height and time of high water are thus 
perpetually changing ; therefore, in solving the 
problem, it is required to determine the height4 
to which the tidM rise, the times nt which they 
happen, and the daily Tariations. Theory and ob- 
ifervation show, that each partial tide increases as 
tha cnbe of the apparent diameter, or of the parnllax 
of the body which prodnees it, and that it diminiiiheB 
u the Bqoare of the cosine of the declination of that 
body. For the greater the apparent diameter, the 
nearer the body, and the more intense iti action on 
the sea ; but Uie greater the declination, the less 
the action, because it is less direct. 

fTW be continued.) 



THE GONIOMETER, 

The instruments which are used for measuring the 

anglrs of crystals ire termed tjoniomeiert. The 
iplest of these consists of a protrsctor or semi- 
!ular scale of degrees, A A, and a small pair of 

compasses or nippers, BB,CC, destined to recesve 

the crystoL 




The eentiv of the pair of compasws ic made 
moveable, like thtne of the common proportional 
compaaaes, so as to |>crmitthe legs BB, and CC, 
to be considerably lengthened or shortened, when 
the two pieces are applied to each other. The fised 
leg BB, is represented as beneath the moveable 
one CC. or radius, raessnring 90*^, and the lower 
end of the centre. pin, which could not be shown in 
the wotid-cnt, is made to At the hole or crntre in 
the protractor precisely at the same time tliat a 
■tud or projo(!tmg piece of brass, being admitted 
into the long perforation of the leg BB, the piece 
becomes steariUy attached to the protractor or Krui> 
drde, oi is seen in the figure. 



The appUcatioQ of this instrument b obviotiA.— 



.) h 



n the 



The crystal to be measured is appl 

compasiCB, which being thus srt, ai 

protractor, and the value of the an. 

ofFat theedge of the tegCC, It i>. v ..;.«4. 

dom that accurate resulta csn thns *'■ <^'>wh.1. te 

the surfaces of crystals are generally too sraaJl or 

too im{>crfcct to admit of sack method of measw^ 

meiit. 

'ITie reJUctivf gouiomeifr^ invented by Dr. Wol* 
laston,. is a more useful and perfect iasirumtmt. It 
ensbles us to determine the angles rven i*t minnlc 
cr)'staU with great accuracy i a ray of ligbt rrfl«<rtrd 
from the surface of the crystal being employed • 
radius, instead of the surface itself, Mr. W . IMl' 
lips has given the faUowing deacriptiiMi and prac- 
tical details for the use of this iaflrameitt, ia kii 
" Introduction to Mineralogy.*' 




A is the principal drcle-t graduated on one 
to half degrees, and divided, for couTcnienf^, 
two ports of iHO'^each. B isa hrosa t>lat' 
upon, snd supported by. the pillar C, » 
oted as a vemirr. F is the axle of the <-irri<- .<., 
and passes through the upper part of the two paUsil 
C £, tlie other ends of which are iascrt^<t >i>t<^ & 
wi3iiden hflsc. G is an axle, enclosed wit): 
earned by means of the smallest circle \ i 
communicates a motion to all the apparaluk 
left of ]. without moving the priocii>at circle 
K is u circle, to which is attached the axle 
prinripiU circle. l(, therefore, we would n 
Litter, it wiU be done by moving K ; and as 
of the principal circle includes that of the ap| 
on the left of I, we necessarily give a motion 
whole instrument by moving the circle K. 

These two movements b^g understood, 
now suppose tlmt we want to meosare a 
rhomboid of carbonate of lime for tnaltnce. 
D be the rhomboid, attached by means of 
one end of a plate of brass H ; the other end 
plate being placed in a slit in the upper part 
circular broas stem O, which posses thi 
tube, to which it is so adjusted as to sllow of 
moved cither up or down, or circularly, by 
of the nut. The tnhe is ftxed to the curved 
plate P, which is attached, but so at to 
motion, to another curved ptate Q, by Deoni] 
pin. the other end of the latter plAti> being coi 
with the concealed axle G, to which a mot 
given by turning the little circle U. By mi 
the pin and the tube, therefore, we have 
tions, in addition to the two before describeil 
longing to the axles of the instrument. The it 
axle, however, may be said to be the ccntcv of tU] 



ions* It wilj, therefore, be of adT«nU^ 
rhdmboid of Ciirtfunaic <»f time should l« 
I nmrly on a line vUh that asle ait [(n*»i- 
I will be «u(Rdr»|ly adjuicetl by meoaa of 
O. Hhich Hdmiu of txAug nwed.or dft- 
tt )ili»sure. 

thin inttrument depends on the re- 
of tbc ]iolish on tbe natural pUnra, 
nrfocra of mineraU ; and Ihul this U 
ca rcry powerful, any one may convince 
looking upon a rcry brilliant plane, held 
IB eye, with its edge nearly touchiniy the 
ind not far distant from a window; ha 
obKTvr the rrflectioD of the btrn very dU- 
Urt oa then luppoic the goniometer, aj 
niKoted. to be diatant from a window 
to twenty feet. Let there be. then, a 
f (the uae of thia ia eaieatial) drawn on 
cot between the window and the floor, and 
parmiitt with the horiiontal barv of the 
If. then, the eye be placed olmoit clo6e 
>aibotd or crystal, a reflection of one of 
lUl ba aeen on one of ita planes. Ixt ua 
hi reflectioa to be in the direction of the 
ted line on the plane ; and it will be clear 
fanot be parallel with the bar of the wia- 
Vmag even with the black line. If, how- 
fa reflection appeara to be like the upper 
e, that ia, parallel with the black line, wo 
; conrince oorselrea that it ia to» limply by 
; tbc crjalal a Utile, by meani of moring 
circle JJ, ao aa to bring the reflectioa 
Aloe* iine. Thia being adjuatod, which 
fl precisely, we then torn the crystal, 
the httle circle H, ontil the reaectioo 
*«r b« seen on the next plane, perfectly 
" amd i^MMi tAe black line. Howcrer, 
Bf the aecond, wc may disturb the lirat 
By perseverance it will be found that 
be AdjUflted hy means of one or the other 
ffttocDta, or by the help of both, and a 
Mieooe will do away the chief difficultiea. 
eetioDa being precise, we are now, by 
circle K, to turn the principnl circle 
arrest«d by a stop on the pillar C ; it 
J found that 180 on the prindpal circle 
With cipher on the remier. In doing tliia, 
Iwc may slightly disarrange the reflections 
pne of crrstol, which may be rr-adjustrd 
moring the little circle !, which will not 
! principal circle A ; we must be certain, 
Aaf mo fjit ii fonnt a tine with cipH^ on 
, at tht tfime time that the rtftection of the 
1 cifmg thi black line. One movement 
, the measurement will have been made. 
irde K, keeping the eye almost close to 
id< «ntil the reflection of the uame bar is 
«<^}oiidng plane precisely upon the black 
--—=■->»:, and the opcratiuu i» cum- 
II be observed what proportion 
-c has been moved, i^ppose 
it« tpc now on a line with cipher on the 
» the vaJge of the on^le. But sup- 
a litll*« more thun I0:>, and leg» than 
twt then be observed vhicA line f^f the 
''•rtitM bat one line vith, another 
drrlf; ; 4U|ipOBi; It to be 5 on 

., is then lOJ o', which is the 

the obtuse angle of a rhomboid of car* 
tit. 




POLARIZ\TION OP LIGHT. 

The foUowinji valunble paper on the polarisation of 
light is by Mr. Goddard, the iuventor of t p^iUri- 
scope and other apparatus on this subject. 

The beautiful phenomena of colors produced by 
the transmission of poUrized light through doubly 
refracting crystals, the Tsrious bands and com-eotric 
rings, composed of rII the most brilliant nnd drlicate 
tints of the solar spectrum, and the diHWrnt forms, 
changes, and modifications, that Ihcy may br msde 
to undergo and cihibit, are ao numerous nnd varied 
Bi to furnish a display of the roost splendid e«|>eri. 
ments within the whole range of science ; whiUt 
their value and importance in the sciences of mine- 
ralogy and chemifttry, from the deep insight which 
polarized light afibrda uf the minute ftructure and 
coDititQtion of transparent bodien, wbidi appear, 
upon every other mode of exunination, to be per- 
fectly homogeot^oua, yet. when viewed in polarised 
light, exhibit the moat cxqnisite structure, (as la 
seen in the extraordinary configurations of apophyU 
lite, anolcine, and many others, displaying the influ- 
ence of laws of combination, of which it is irapoa- 
siblc, by any other means, to obtain the least know- 
ladge.) renders an exhibition of these experimeoti 
not only interesting, bnt most desirable and im- 
portant. For this purpose, after having tried nn- 
meroos eiperiments upon the different methods 
now in use, I have constructed a poUriacopef 
adapted to Mr, Cary'a hydro-oxygen microKope, 
which is capable of exhibiting, upon a disc, on a 
highly msguified scale, all the beautiful and curiona 
pbenomena of this interesting brant<h of science. 

But, previous to describing the polarizing appa- 
ratus, and the effects that may be produced by 
means of It, It may be as well to give a abort and 
popuUr explanation of what polarized light is j 
and, to do this, we must notice the principal hypo- 
thesis upon which the lluygenian or nndulatory 
theory of light is founded, at least so far aa relatea 
to the phenomena under consideration : but la bo 
doing, I beg that I may not be understood as advo- 
eating this theory in opposition to any other, but 
merely using it as affording a popular explanation, 
which those who give a preference to its rival will 
have no difficulty in understanding, and can, if ther 
plemse, substitute the language of ita rival, the cor- 
puscular theory. 

The following are the principal poatulata, accord- 
ing to Sir W. J. Herschel. upon which this, the 
undulatory theory, is fouudi-d. 

1. It is supposed that a rare, elastic, and Im- 
|>onderable medium, or ether, filhi all space, and 
pervades all material bodies, occupying the intervals 
between thdr nM>lAealei, and poasesaing inertia, but 
not gravity. 

2. That the molecules of ether are susceptible of 
being set in motion by the motions of particles of 
ponderable matter, which motion it communicates 
in a similar manner to adjacent molecules ; thus 
propagating it, in all directions, according to the 
same mechanical laws which regulate (he propaga- 
tion of undulations in otlier elastic media, ns air 
and water, according to their respective constitu- 
tions. 

3. That vibrations commanicaled to the ether, 
in free space, are propagated, throuf^h refractive 
media, by means of the ether in their interior, but 
with a velocity decreasing with its inferior degree of 
elasticity. 

4. That when regular vibratory nwliona, of ft 



da 



MAGAZINE OF SCIENCE. 



jiroper ktndt are proptgited throagh the ethfival 
tnedis, aud pau into our eyrs, And rtuich and agi- 
tate (he nenrra of the retina, they produce in ni 
the sensation of lifht, in a manoer more or leu 
Anulogou« to that in which the TibniCions of ike air 
affect our auditory nerves in producing soond, 

5. That aa, in aoand, the fre({uency of the aerial 
Ttbrationi, or number of excursions of each mole* 
cnU of air, deternoinea the note, so. in U(;ht. the 
frequencj of the Tihrations made on our nerves, in 
m given time, by llie ethereal molecule, determines 
the color of the Uf;lit : and that, hh the extent of 
the vibrations of air determines the loudness of the 
sound, so the extent of the vibrutions of t)ie ethe- 
real molecule determines the intensity of light. 

To understand how waves are produced, by the 
vibrations of the particles of an clastic mcdiutn, we 
have only to atudy the waves produced upon the 
surface of a pond of water when rain is falling ; it 
will be found that the particles of water driven down 
by a single drop of rain force the adjacent ones 
upwards, the nlr above, in coDse()uence of its being 
more elajitic, yieMing sooner to the pressure exerted 
by tlir difplaced particles on those surrounding the 
point of disturbance. Tbtis a wave is raised round 
this point by the momentum of the falling drop, 
and, AH sDon as such momentum is spent, the effect 
of i^ravity draws the raised particles down to the 
common surface nf the lifjuid ; the momentum, 
however, which they have acquired in this desoeat, 
carries them below the level, or point of rest; and, 
in descending below this point, they cause, among 
the adjacent particles of still water, ■ motion similar 
to thnt by which they were themselves actuated by 
the falling drop. The second wave thus produced 
will, in its descent, cauae a third ; and thus a series 
of waves, decreasing in height as they increue in 
breath, will be produced in rings, vibrating up and 
down, as is easily proved by placing a cork upon a 
smooth surface of water and producing a series of 
wives, when the cork will produce the same vibra- 
tiona AS the particles of water upon which it flouts. 
Such Tihrations present the appearance of waveir 



as the motion is commnnicflte6 from or 
thoM odjaceot. as u reprc*ented by 
we may suppose to be a section of tbttl 
water at tba time of the appearance oti 
the dots being the separate porliciea. 



j'AAa 



donhb 
ofH 

le ^1 
d. agl 
Co hai 

e rti 



Dr. YouD^F, in applying the undulah 
light to the explanation of the v: 
nomena. while considering tlic rcsulta «f 
Brewster's researches oa the laws of donhb 
tion, first proposed the hn'^tliMii of 
vibrations, which hu since been sbci 
necessary consequence of dynamical pi 
is most importiint to tlie explanation of 
These vibration* he illustrated by the _ 
of undulations along a stretched cord, agl 
one end. which, supposins a person to had 
huud, and, by moving first quickly op 
wave will he produced, which will run olc 
to the other end ; and then, by a aimilarj 
but from the right side to the left, nnot 
be produced, which will run along the 
former; but the vibrations or undutatiMii 
will be in planes at right angles to each oU 
dependent of each other, one being in a i 
plane and the other in a horixonta] plai 
according to this theory. Fig. 2 maf be i 
represent a a ray of ordinary or anpoli 
I have chosen this representation of a a 
ordinary li^l, which is a drawing of 
Woodward's beautifully simple card ce 
conveys at nnre to the mind a distinct D 
planes in which theribrations take place. 
light we may therefore concdvr to cona 
cesainn of systems of waves following 
with immvnee rapidity, and comprtstog 
number of rays, the vibrations of whie 
farmed in every possible plane. 




CTa be coniimei.) 



ELVDORIC PAINTING. 

Tbis method of painting, called elydoric, was in- 
vented by M. Vincent, of Montpetit. It takes its 
name from two Greek words, denoting oil and water, 
both these liquids being employed in its execntion. 

Its priucipal advantages are, that the artist is able 
to add the freshneaa of water colors, and the high 
finishing of miniature to the mellowneu of oil 
painting, in such a oaanner that the work appears 
like a large picture seen through a concave lens. 

The following is the manner of proceeding : — 
A piece of very fine Uocn or white taffety is sized 
with starch in the most equal manner possible, on 
pieces of gloss about two inchca square, in order 
that the cloth may be without wrinkles. When 
thcfe ore sufficiently dry. a layer of white lead, 
finely ground in oil of pinks or poppies, (the whitest 






that can be procured,) is to be appQ 
with a fwllet knife. To this la^er, whea 
to admit of scraping, more is to he 
cessary. 

A,s it is of very great importance for 
vstion of this kind of painting, that the 
free from oil, that they may better imbt 
laid on them, it is nece^ary that thi 
mode very smooth, auil that it be very 

The ariijA is next to procure a oir«i< 
about two incites diameter and one-foo 
in height, extremely thin, and painted 
inside. This circle, is to contain the 
surface of the picture. 

Water distilled from rain or snow la 
any other ; ordioary water, on account 
which it contains, being pemictous tu 
painting. 



MAGAZIVE OF SCIEKCB. 



99 



be finely IrvigBted betvcea two 
i-fiilly preserred from dtiat, and 
)U of p«>ppiea. or any other cold 
rhicb thoiild be as Umpid as water. 
r« being grouod, arc to be placed in 
m a piece of glaas, end covered with 

lU beiD^ thus prepared, the subject to 
to be fiuDtlj traced with a black*Iead 
it the piMM of cloth above- menliooed. 
tbm to be formed on the psllet from 
M nnder the water; and the pallet 
nl, ia the left band. The picture Is 
wecu the thumb and forefiugcr, aup- 
D reuldle finger, and the necessary 
lird and little fingers. The hands reat 
of a chair to giTe a full liberty of 
rork nearer to, or remuriag it far from 

kg made the rough drangbt with the 
lab, the circle of cupper, which is to 
pricture, is to be fitted eiactly to the 
tilled water is then poured wilhiu this 
Hi to thr height of onc-cigbtb of an 
•ye is held per]>endicular over the 
third Anger of the right hand, while 
lid rest ou the internal right angle of 
The work ia then ;to be re-touched, 
hv oolor and softetiiug as be finda re- 
leon as the oil swims on the top the 
hft off, and the picture carefully covered 
l^au. and dried in a box by a gentle 
dry enougb, it is to be scraped nearly 
i knife, the artist repeating the former 
tit latiiried with hia work. 
k period that the advantage of this 
wrlictdariy shows itself fur the purpose 
c» the water pourrd on the picture 
ry fault of the pencil, and gives the 
ecting Bud perfecting it with certainty. 
iiork is I'misbcd it is put aoder a fine 
birii the eaternal air is excluded, and 
ncaas of a gentle heat. 



Ktri 



lICITY OP STEAM. 
To Iht Ktiitar. 

■ the opportunity of mentioning, in 
be subject of the electricity of steam, 
« which occurred to mywJf some time 
■oakiDg an experiment, in which 1 was 
a gas-holder, the gas and steam which 

off from two retorts containing re- 
r and water. 1 was very much sur- 
irre, shorlly after the commencement 
meat, the diichnrge of at lenat two 
cs from the top of the glass tube which 
•eertaining the quantity of gas by the 
w^ter contaiued in the Tcssel. My 
the roommt being otherwise occupied, 
heed to the circumstance, thinking it 
t this manifestation of electricity was 
DC pecnliar chemical action resulting 
|m of the gaaes. The accidental dis- 
letrieal phenomena in ateam genented 
imntt, inclines me to thinli otherwise 
vUl b« much the beat judgt* whether 
ton of this circumstance will assist, 

•0 feebly, in the elacidation of the 

S. U. TAYLOa. 



ON MANAGING BALLOONS. 
7b M« Editor. 

StB. — A taggestion having occurred to me to 
render balloons more manageable, I beg to submit 
it to your scientific readers, it consists in baring 
a fire in the car, and a tube (open at the top) from 
the fire or stove to pass through the balloon, (firom 
the boUom thnragh the top.) bat not so as to touch 
the gas, the hole through which the tube pasBM 
being intended to be closed up with cloth, so thit 
if the labe were removed, it would havi; no aperture 
for the gas to escape, as the rJoth tabe would be 
left in the cavity. This tube must have a valve in 
it near the bottom which can ahut or op«a the pu- 
sage at pleasnre t and it is by meana of hot slam 
or heat pMoed thraogb it that the balloon is to be 
coofed to ojcend and deocend. When wished, then, 
for it to ascend, the ralve must be cansed to o^n 
the passage, when the beat passing through the 
balloon will dilate the gas, and the balloon will con> 
aeqocntly rise. For descent, then, the valve must 
be closed. But tbe balloon must not be nearly 
full, otherwise it could not expand, but most burtt. 
No hBllo.iit will, it is presnmed. be required, and 
probably some progreasion might olso thereby be 
obtained, by employing a sort of nearly horisontat 
sail and inclining it one way or tbe other, as tko 
balloon ascemls ; and the rrsihtance of the air woul4 
then, it appears, cause the ballooon to progrest. 
Suppose, then, the oeronaat wiahed to go eastward, 
he must let a current of hot air pass through the 
balloon, and at the same time incline tbe cast end 
of bis soil opword. and then close tbe posasge sn as 
to let the gas cool (or, if any method should occur, 
be may send in some cold air.) and as tbe ballooa 
would thereby descend, he must turn the eost end 
of the Mil downward, and tlie balloon would go ia 
the coDtmry way. 

But tbe car ought to be fire-proof. It does not 
seem impossible to produce the same effect without 
Are by means of an apparatus in tlie car to con- 
dense snil exbsust the gas : but then the tube maat» 
instead of passing through the balloon, open into 
tbe bollooa itself, and this method would be tctj 
laborions. 

But with respect to ballast. 1 am obliged to con- 
fess my ignorance why any it ever required, as it 
seems that the only reason v^hy it is adopted is 
because too mach gas is put in the balloon, wliichf 
if not fall, most eipand as it rises into a more raro- 
fied otmosphere, as, the more the qniwdc air be 
rarefied, the more so will l>e the gas within ; and, 
if the batluoii be full before it rises, it cannot eipottd. 
but may burst. 

The machine Utely exhibitpd at the Polytcthnie 
luatitation of a cross sail applied to a ballooo. 
fteema to be the same as was invented by me, and 
also by another person, signed '* Volitor.** several 
years ago, and. which, on being turned round, roi 
in the air. (Sec the rhiloMOpAical Maffustne^^ 
1814, and the Afec/Mraics' Jommat, £(e.) 

L. OOMPKnTI. 
Oral, Kemti^gtoa. __ _ 

"^ form Pignreu in lUti^ on an Ejf^.— Design 
on the shell any figure or ornament you please, with 
melted tnllow or any other fat oily substance ; then 
immerse the egg in very strong vinegar, and let it 
rrmaio till the acid bos corroded that port of the 
dhell which is not covered with the greasy maUer : 
those parts will then appear in relicC exactly m 
jon hove drawn them. 




40 



MAG/VZINE OP SCIEXCi:. 



MEDICAL RECEIPTS. 

SNUFFS. 

Tax baM of all rauITi is, or oaght to be, gmnnd 
tobaceo, the part of the pUnt tt6«d b«iag the ttalka 
of the plant. 7*he following are general directions 
on the manufacture of it : — 

Perfitirwi Snuffi. — The tobacco being groand 
and sifted, aa the wented snuffs do not require mueh 
pungencf. it may be mixed with maboganf tawduat, 
or that from rose-wood, or else the pure Ivbacco pow. 
der may be soaked in water, (the woUr being 
serriceable to steep cabbage and lettuce leaves in to 
make "penny Havannaba;'') then pressed nearly 
dry, then dried, afterwards moistened with rose-water, 
or orange flower water ; and finally sufficiently dried 
for sale — a htUe oil of tartar being put into all the 
moist snuffs to keep them damp at all timea. 
Fr«oeh innff is scented with the root of calamos 
■romaticas. 

Macouba Snuff" owes ita flavor, and perhaps its 
sedative powers, to theprevious fenneotatioD of the 
tobacco leaves by moi6t<ming them with cane juice, 
ond probably producing iu this way an acetate of 
the narcotic jmuciplt; of the tobacco, if such exist, 
M there is reason to believe there does. 

Lundjcfoot't Snuff, which has a burnt odour, 
somewhat like malt, is prepared by partially torri- 
^ing the materials, and is imitated by moistening 
any light colored snoff with empyreumatic oU. 

Bye Snuff. — Triturate and mix together, in a 
marble mortar, 5 grains of sulphate of mercury with 
2 scruples of liquorice root, powdered. Grimstone 
and others disguise this by various ingredients. It 
is a powerful errhine in producing a diacharge from 
the nuae, wheo snuffed up in small pinches, bat it 
is not Kafe. 

Cephalic Sniiff. — The following are various re- 
ceipts recommended for this snuff: — Mix together 
oqoal parts of tlie leaves of asarabacca, marjoram, 
mod of the lily of the valley, dried leaves of asara- 
bacca 1 ounce, flowers of lavender 2 drams, dried 
leaves of asarabacca 3 ounces, leaves of the dock 
■nd flowers of lavender each I ounce, sage leaves, 
nsemsry, 1Uie« of the valley and the tops of sweet 
marjorum, of each 1 ounce, with a dram each of 
asarabacca root, lavender flowers and nutmeg ; 
pound and sift it very ftnely. 

VeUoiP Snuff.— \ei\ow ochre the sbe of an egg, 
add chalk to lower tlie color, grind with half an 
eunoc of oil of almonds till tine, then add water by 
degrees, and two i|>oonsful of the mucilage of gum 
tragacanth tiU you have about a quart, mix tbia 
vidb pDrified snuff and dry it ; then aift it through 
a veiy fine sieve to remove the color which does 
sot adhere to the snuff, and moisten it afterwards 
with any aceoted water that may be deainible. 

Taltac {Snuff) Perfvme aux Fievrs. — Put orange 
flowers, jasmine, common or musk roses, or tube- 
lOMa with the fcuuff fur a dny and a night, and sift 
them out ; rc|)eat this as often as necessary. Snnff 
doea not heat with the flowers. .Snuffi are also 
scented with musk, civctte, ambergris, the essence 
of bergamot, rose-saCer, elder-flower water, itc. 



Cones ffoid 



KINDS OF CAUPIiqH^,, , 

AowpA Camphor. Ijinrtl Camphor^ Csmphora, — 
Obtained frum the routs and shoots of the Laurua 
camphnra, L. cinuamouinm, and Capora cunindu. 



by dTstiltation with water 
Jnpan. 

l^ryobaimm Camphor. — Very littie ol 
pbor comes tu Europe, it beiog carried 
where it sells for aboat thirty times 
their own laurel camphor. Obtained 
spUtting the Dryobahinns camphora ; 
this tree containing camphor mixed 
camphor. It cumea from Sumatra and '. 
Refined Camphor^ obtained by subtil 
one-sixteenth its weight of lime in a ^ 
beat. Camphor is stimulant, narcotic 
retic, in doses of 5 grains to 1 scmple, I 
bolus : too large a doae occa^aa vonntil 
rnlsiona ; its effects are eooateraeted by 
msybe faapeaded In liquids, by means 
yolk of egg, or almonds. Camphor 
boxea to keep insects from them, and 
fireworka ; it renders copal soluble in 
tJal oils. 

lAquid Oa^kor, Oil (/ Campkor. 
liguida, Oifum cwmphara, — Prom 
camphora, by piercing the tree. 

Rofemary Camphor. — Obtained fwU 
a careful redistillation, without additi 
third of thr oil ; the reaidunm affords 
camphor ; on separating which, and re-J 
remaining oil two or three times, the w 
camphor, amounting to 1 ox. from 10 
may be obtained. 

Sweet SfarjttrHtn Camphor. — Obtaa 
manner, nbout 1 oa. from 10 of the oil 
tile ; when act ou fire, it soon goes 
Cttmphfir, 1 or. from 8. 

Latmder Camphor, 1 ox. from 4, e 
of oil. 

Thyme Camphor. — Crystals cnbica1,d 
a liquid solution either with nitric or sal| 
is precipitated from nitric acid in a glul 

Soap Camphor. — Obtained from 
tion in water, adding muriatic actd, 
curd, wothiug it with boiling water, ani 
to separate the liquid rialne. It is i 
Btearic and margaric acids ; used to m 
which ore very white, aa neat aa wax i 
give a brighter light, bat do not last ao 
Turpentine Camphor. — Obtained fs\ 
turpentine, by passing muriatic gai 
by which means it will yield about iti 
of a kind of artiticial camphor, not 
dilute nitric acid, and when dissolve 
nitric acid not separated by the additic 
Cilrrm CatHphor. — Obtained from t1 
tified oil of citrons, exposed to miuiat 
absolves 286 times its bulk, or ne 
weight, and yields about 9-lOtha of 
It will be seen immediately that 
are muriates; the first, or that from 
the muriate of cumphogeu, or artifld 
oamphogen being the iupposed bate ol 
while the citron camphor ia the man. ' 
citrene being the new name of the oil 

Common Camphor ia called the proto 
pbogen, and conaistji of carbon 10 pal 
8 parts, and oxygen 1 part : by di 
nitric acid it absorbi 4 parts more of 
becomes camphoric acid, 

Voii. 1 oiuf 2 qf Ihit Magarine art noi 
jfontly bound in Cloth and Jjetttrad, 



U>NOo}< ;— PrUUcil by I). k'sAMCW. 6, Whilo UoiMLaiK.Uileiiad.— I'uOUftbcd by W. BsirrAlu, 11, Vi 



THE 



lAGAZINE OF SCIENCE, 



^nd ^tbool of Stm. 



.0.] 



SATUBDAV. MAY 8. I&4I. 



[l^rf. 




42 



MAGAZINE OF SCIENCE. 



FILTERING MACHINES FOR WATER, 
Tnc Approach of summer, ind the Tut amount of 
ftnimaj .-intl vcf^etible life which it gi^ra rise to, co&. 
taminating no mncb the wiiter of ponds and streams, 
induce n» to offer this week a few remarki onjl/trr- 
mg, with the view of directing our rejidcrs to a 
kaowledge nf the construction of some simple filter- 
ing machines. 

The first of these machines which we sh&U notice 
ii Messrs. While and ATeline's '* artificial spring," 
in which the water is made to filtrate upwards by 
its pressure i^ninst the under side of a stone, the 
quantity filtered depending upon the area of the 
atone, and the height of the reacrroir from which 
the water descends; but with a head of 35 feet, 
which can be obtained in most houses in l^ndan, 
a stone of 10 inches squsre will filter nearly 30 gallons 
per hour. Tlie engraving. Fig. I, exhibits u vertical 
•ection of the apparatus. A is the cistern which 
reecircs tbe water in its impure stat« : it bos a ball 
float and lever to keep a constant head of water 
orer the pipe B* and likewise to prevent any air 
])assing down it. Tlie pipe B is shown broken 
off, that the space between may be considered as of 
any required length. To the lower end of the pipe 
there is a nozzle C through which the pipe passes, 
which causes the water to shoot up against the under 
surface of the filtering stone F. Through this stone 
the water oojtes with great rapidity, leaving the 
■ninialculic and other impurities in tiie lower part 
or boMD £ of the marbinL*. from whence they are 
drawn oB* occasionally by the cock G, and carried 
away by the waste-pipe H. When the filtered water 
rises in the reservoir above K, to a certain height, 
the filtration i* stopped by the rising of the float L, 
which by its lever or rod N, shuts a cock O in the 
supply pipe. When the stoue has become charged 
with a deposit on its under surface, it is capable of 
being cleansed by the scraper S, which is turned 
round by means of a handle shown st the bottom of 
the reservoir K, the luia paBiiog tbrongh the stone; 
provision is thus nade for reviving the filtering 
properties of the stone whenever required, and with 
Tcry little trouble. 

A very old coutrivance for filtering water, but 
which has been the origin of moat of the more recent 
ipporatas for the purpose, consists in nearly filling 
the two legs of a pipt^, formed either of metal as in 
Fig. 3, or of wood as in Fig. 4, with washed uand, 
leaving merely ■ ajiace at B and B to receive the 
turbid water, and another at C or F for the filtered 
water to run off by. The chief objection tu these 
machiDes is, that they soon become foul, and con- 
sequently useless, until restored by cleaning, and 
this task, OS gcnt'rnlly performed, issuch alsboriouSf 
tcdinu<t, and alopping one, that these filters are 
mHunlly abandoned in a abort time. 

The engraving, Fig. 5, represents an apparatus of 
a convenient form, by Mr. James, of Knightsbridge. 
It consists of two vessels, A and B, of stone-ware, 
placed upon a strong stand C The upper vesael, 
which is covered, recelvea the impure water in a 
chamber D, at the lower part of which there is a 
large aperture, stopped by a sponge E, which de- 
tains the grosser impuritie* : henre the water passes 
through a finely-perforated eartbeuware plate into 
a layer of six inches of prepared charcoal, through 
which the water filters, and is thereby purified from 
any noxious smells, as well as any (Inatiog im- 
poritic-s ; it then pa5&es through another perforated 
plate G, and is received at H into the separate 



vetiael, which is b ttone-ware cask, from whitA it 
may be drawn off at pleosnrc by the cock. 

A very simple method of freeing water (rom As 
impurities by means of the capilUry ottractiasi af 
fibrous sobftances is represented in the at * 
engraving. A ia the reservoir. H the lowe 
partment. C an open tube soldered into tke 
of the reservoir, in which is put a wick of 
or wool, (the latter is best.) with one end im 
in the bottom of the rrservoir, whilst the otlm 
end hangs down a liuLe below it, forming a kind 
of syphon. The water in rising by ibe capillary 
attraction between the (ilamenta, deposits tha 
gross matter floating therein, and desccnda in a 
comparatively pure ttate into the Teasel B, or iiU 

• j«g- ^ 

The engrtrlDg, Fig. 2, repreoents an npperMn 
contrived by Messrs. Williams and Doyle, fcr tho 
pnrpoec of separating the salt from eea^wster, fcf 
merely causing it to percolate through « body flf 
sand under mechanical compression, and thua to 
render it fresh, Conld this object be obtaiii«d bf 
such neons, the invention wontd doubtleM be bM 
of the utmost importance to navigatioa, ea it woaU 
render a store of fresh water unneocaoory, thefrf^ 
affording additional stowage for provisions or cargo; 
but we ore not aware of any experiments provf«( 
that substances diaeolvedr and rhemically rombinei 
with a liquid, ean be separated by filtration ; «c 
therefore apprehend ihot the apparatus wonld he 
ineffectual for the object the inventors had in view, 
ntthough it may prove very efficient io freeing water 
from any impurities floating or aaapeoded in U* 
Hie following description of the eogrtLving (wUek 
represents one of the several modea of cooatmrtoQ 
pro|MMed by the inventors,) ia derived from "^ 
specification of their patent. A ia • psrt of ' 
supposed to contain sea-water. B • tube 
ing therefrom, made fast by bands to tbe 
apparatus D D, which ia a atroof aqvarv 
of wood, lined internally with aheela ( 
which are cemcntfd together to prevent the 
sition of water. TTiia part of the apparatna 
in section, that the construction and 
may be aeen at one view. E is the lower 
where the water u first received. F is a rtn 
of open frame-work, supported on fifc M 
F F. Over this abort frame ia nailed • 
of copper, pierced with naiuerou5 small holes, 
the perforated plate ore eereral layers of 
cloth, or woven horte-baJr, and abo«e 
body of sand, filling up the entire 
the top is placed a sliding cover L, which ia 
upon by a strong acrew M, working throagk a 
nut N, which is supported by curved iron 
tending from opposite sides of the trunk. Thei 
having been curopressed, by the ogenej of 
screw, into a more dense and compact mMi 
vented from rising by the pressure of tl 
which percolating through the minute Jntei 
regain its level, deposits its salt, and rax 
the pipe O in a freim state into a vexseJ P pi 
receive it. When the sand bu become sal 
with salt, it is to be removed by taking 
screw and the pressing-board L; the nun 
R R may then be opened by uniscrewiog the 
when the other materials may be eooily siAed. 
matters being completed, a fresh quantity of 
may be taken from the ballast of the ship, am 
process of filtration continued aa before- 



tr«ak. 



MAGAZINE OF SCIENCE. 



rO STEEL OF DIFFERENT 
(SITJONS AND (DUALITIES. 

f rtn t).,- innnafacture of rut itecl st Si. 
I J maDufactory of iwordi lad 

n .' Houttieni part of the Ourat 

l^oloHcl Aiiuof detcribes thn prooeNM 
b*( rasnaToctury to produce the tteel la 
pbl<« bj the fnsioD of b»n of iron ind 
(Bi of blut fiimace«. The peculi&ritj 
hm consbts in tliii ; that ima n put 
iifalet covered wilh charcoal to submit 
If ttnaeatetion , whilst in England iteel 
tmenlcd is empioyed. In other respects 
liaf new in the method adopted, but it 
*v1ceBble to atate, briefly, the toeaoi 
the author of the memoir of obtaining 
brent TArietiei in its compositioa and 
I*h0 foUowiuf arc hia observationa on 

leam idopted for the fobrication of 
IBdeat to ifaow the principal cauies 
ID vary the «faa1itiea of this metal ; aa, 
the quantity of carbon absorbed by the 
iBAtore of the iron itself. As the firaC 
tn Buy be regulated at will, it requires 
1/a, and the second need not now be 
I will therefore confine myself to the 
ksTC formed, which are the resiUta of a 
r of experiments. 

p purer the iron, that is, the more free 
W Ribitincet, the better will be the 
Bflnm H ; but the cementation will re- 

IbDC. 

'qualities of tofl iron are not to be pre- 

Ittle iron ; for if the hardnens of the 

ted by the carbon it conuins, it is prc- 

iroo, of the same quslities in other 

of the iron to be converted into 
on the quality of the iron ores 
the preparation of the iron. For 
i ium procured at ZUtnnnst, from the 
I from the Tearoincic mine, is preferred 
,theother mines in that net^hboorhood ; 
iCrom the iron works of Tugikk pro- 
ji fuperior quality to that from 

eiipgnngi from the sworda made 

piwhice cast steel of a quality 

to that of the ehppings of iron. 

bar* of iron which have been baried 

fer some time produce steel of a 

>r to that obtained from iron which 

Illy manufactured. This fact wa^ 

|a in the most ancient time, but Euro- 

Ifoi^otton the leasoun of their roaaters in 

kvc been in arrear of those natiooft, not 

H of making the be&t steel, hut also in 

^ of the slfpis by wliich the perfect 

I ,»-miux,\y atcertoined. If we are well 

cutler at least. Mr. Weiss, 

i.iii. v 1 the superiority for making 

^B^ haa remained a long time tmder 

f aleet is of better quality when the 
i ore hofDOgeneoos and of equal sise. 
i ftoel is softer when tlie ojteniitg in the 

trz 



or pieces of iron which have 
■d to the air produce worse 



presauR of the iron be equal up lo the tine the 
lid is put un the crucible. 

" 9th. If the workman have neglected lo put the 
lid DD in time, he may reader the steel of good 
quality by adding as much iron as is necessary to 
raise the metal to the proper height. 

" lOtb. If at the time of tlie final proof the steel 
does not send forth sparks stitficirntly bright, the 
evil indicated by this bad sign may be remedied by 
introducing throuf^h the opening of the crucible two 
or three pieces of iron of the weight of about half a 
kilogramme, 

" Uth. The fusion of the steel mixed with pow- 
dered charcoal or soot in determined proportiotiB« 
and in a closed crucible, as proposed Messrs. 
Mushet and Urcan, mi^bt, indeed, produce steely 
but ita dei^rec of hardness would be moeh Ifln 
certain than on the plan 1 have described. In fact, 
if the charcoal be in excess the ateel will become 
too bard ; if there be not eoougfa, the metal wiU be 
difficult to fuse, because a part of the charcoal will 
be vohitiliaed. 

*M2tfa. The addition of other metals, such as 
platinum, sih'er, or gold, in the proportions of I '& 
to 1*2 per cent., aoraewhat Improvca the quality of 
the steel, but the more pure the steel is, the lesa 
advantageous do such additions become. The effect 
of the addition of these metals consists principally 
in making tlie steel more easily forged, the propor- 
tions of carbon and iron being eqoiU. 

" As to brittle metals, their mi^iture with ateel is 
always more or le.4« injurious, and this becomes 
more apparent In proportion u the quantity of the 
alloy is increased." — Afonttfur Industriet. 

BOTANICAL NOTICES. 

ROOTS. 

The root is that part of a plant which grows away 
from tlie light. Ita use is to absorb moisture for 
the support of the rest of the plant, and generally 
to fix. it to whatever it grows upon. 

The root la called ttrrtatricl^ if growing in the 
earth, aa the generality of roots do ; pmraxitie If 
attached to other plants ; thus the raialetoe growa 
upon the thorn without contact with the soil ; 
aquatic if suspended in water, as in the duckweed 
and numerous other water pUnts : this kind of 
root does net fix the plant to any particular Rpoi, 
not being itself attached to an immoveable sub- 
stance. 

Roots differ from stems in not bearing regnhir 
buds upon them, and in growing downwards : t))ey 
consist sometimes of fibres only — at others of vari- 
oasly>Bhaped fleshy portions, oiled the body of the 
rooL This latter part is intended as a storehunso 
of food, and to eqnaliae the supply to the stem, 
when the other parts are impeded in their forniathm 
and re-gular artioa by drought. The fibres are, 
however, most esseotial, and alonf! ran be considered 
the true root, as it in by meann of tht-in only that 
moisture is drawn from' the earth and L-onveyed 
upwards. Their curious and beautiful structure is 
apparent in the first germination of a seed, in a 
vigorous and young root when removed from the 
earth, and in the fibres of a hyacinth growing la 
water. In each of these cjuea the end of every 
fibre will he found to terminate in a delicate, white, 
and spongy point, called a spongiolc, and which la 
more than any other part capable of rapid ah&orp- 
tJon. Owing to it« extremely tender nature it ia 
not adapted to long-continued action. The spon- 
giolea, therefore, and often the fibres which boor 



*^ 



44 



MAGAZINE OF SCIEKCE. 



Ihem, die ava; at the close of each growing seaaon. 
being rt'jploced by fresh uuci when the pUnU 

jeTITC. 

The fibivwi roet ii of three virietief. In the 
tinrt It contiftlaof simfilc uobranched fibre*, iit the 
duckweed it is fine like & thread, (I,) — in the 
Jiyaciuth Bud the orcbiftes like strings — and ia the 
acrrw pine so thiuk b8 lo resemble stout and ittroog 
poles, sometimes two inches in diameter. In the 
second variety, the hbrc» arc more or Iras bnuicheii, 
(2,) as we se£ io ordinary plants. In the third 
case, the Abrea are thickly clothed with long dowDi 
(3,) so as to present a shaggy appearance — this is 
ohfterved porticulArly in those gnusca and Kdges 
which grow upon n sandy shore. Tlie fourth vaneiy 
exult in trees, where year after year the fibres 
become changed into a woody rabstanoa, increasing, 
spreading, and strengthening ; antil at length they 
form a mau anderground, similar to the stem aod 
branches above, not merely ia vppearanw, but 
general structure, (4.) 




Ill I 

The tap or Juf\form root ; a fleshy root, thick at 
top and with the lower part gradanlly tapering down- 
wards ; it ia attended with but few fibres, and these 
are abort and branched. Carrots, (1,) parsnips, 
■nd radiahes, are examples of tap-rooted pUnta. 
In the turnip, (2,) it takes a rounder form. If the 
root perish at the lower extremity, so as to end 
■bmptly, it [a called a pnemorK or bitten root (3.^ 
The plaintain and the devU'a bit, (scabiosaauceisa,) 
sreof tUikiod. 




^ I 3 

The knotted or htiiercuaUd root is extremely 
varied, in the dahlia it consists of a number of 
fleshy taperiof* bodies united together, (1.) la the 
dropwort the fibres of the root are loaded with 
spindle-shaped knots, (2.) The roota of some of 
the orchis tribe consist of two finger-Uke portions, 
(2,) or else of two solid bulbs, (4,) one of wliich 
diea away each year, while a new one ia being 
formed : in a few these bulbi are ai a distance from 
each other, (5.) In the bird's-nest orchhi the root 
4»nBists of a mass of fibres, interbdng each other, 
(6i) and iu the coral root, (coraUorhixa innata.) it 
resembles the branching of a piece of coralline, [7.) 




Tlie aboTC are truly roots. The following an la 

reality under-ground stems, but as fl— * iiOl 

lately been comddered roota by bot tst 

still called such by otlier persoos, thi , ^^zn 

classed. 

The tnitbaut root is • root to which a bulb b 
attached : it b divided into the wolid butb, oa t9 sco 
in the crocna, (1) — this is often calkJ a carmm. 
The coff/rfif bulb, as in the onion, (2.) The •rmif 
bulb, nbich consists of a number of thici: lesrves 
folding over each other, as is wcU knowu to be Ihfl 
case with the white and the ycUow lily, <3.i Aa 
aggregate bulb consista of a number of bulbs uaitad 
together, u in the guiic (4)— ewih of tlieM sru- 
rately is called a dote. Roots of this dcsi-ripaoQ 
are in their nature correspondent to tlt^ luf ait4 
flower buds. The; bear from tlicir cecire upwi 
mostly a aingle nnbranciied flower stalk imd n 
lesTCt, with numerous simple fibres ^m the 
part. Also during the progress of their g 
small bulbs grow around the lower end at the 
one ; these are called off-teh, and beiaf se|ii 
grow into other plants, exactly similar eren 
their shades and stripes of color to the on 
It is by means of these that tulipa, orocuMii 
cintha, &c. are propagated. 

flr^ ^^^ iJUJBk 

I 9 2 

The granular root is one ia which the main , 
of the root are attended with a number of 
grains like bulbs. In Che white meadow snii 
(1,) they are brown and shaped like on onion. 
the pUewort, (2,^ like grains of wheat both in 
and form ; and in the wood sorrel, (5.) rei 
green, and formed of fleshy scales foldini; overi 
other. The root of various grasses m knotfied! 
a necklace, (ij^tbis farm, however, ia ool 
atant, but ia Uie result chiefly of waul of 
moisturt. 

I 8 S 4 

The inhertma root is one which has flfsiiy 
attached to It. These tubers remain perfcet 
the root or %tem which bears them h.: 
being fumishrd with ffudx or eye», B' 
they sre cnpablr of growth ; each n. .;:« ..^..«t 
year producing a plant similar to that whiefa 
them. Tlie potatoe, (fiG;ured below, "l EUid the. 
salem artichoke, ore examples 




The crerping root, (aoholea.) is a dud 
which £row8 horixontally &nd quickly, 
mostly jointed, throwing out fibrr* from its 
joints downwards, and one or more shoots uj 
whenever it arriTcs at or approaches the 
This root is so tenscioos of life, that if brokeal 
small pieces each of these will Tcgetate, pi 
as mtoy pltots ; heace the diffioultjr thcrv is Ib 




MAGAZINi: Of SCIENOK. 



45 



the eoDcb gnus, (1.) the brtlbinc. and 
which have o cteeping rout ; henoe also 

cxteaaiun and grovtb of lucb pUnti as 

^w, the mint, (2,) the cott'flfoot, &c. 

aria, (3,) the root appeara jagged at the 

cat into teeth. 




^Mn^ or rAJxomd — a thick, fleshy, and 

p>ot, gm^tng: occasionally apoo, hut more 

rjuBt un<ler the aurface of the ground — 

nying at one end aa U increases at the 

M furaUhed at irrcgalar interrala wtth 

. which each year afford freah leaves, 

The orris root, the ginger, and the 

n eumplea of the rhiioma. 




bIiat function of rooti to supply moisture 
of the tegFtiiblc. is rendered evident by 
var manUtstcd by plants to increase and 
roots according to their wants — thus 
aa ^rovr la dcaerta, on dry and hot 
naked rocks, hare asoally very long 
fibrous roots, which extend to a coo- 
below the Btuface, whence more 
attainable. Orchideous and other 
throw out fibres from their Htema into 
if in search of more food than their 
oan famish ; a pUut or tree distorbed 
iteee of growth, and injured as to the 
roots, will iofallibly die, unless it can 
w oat others ; a fact well known 
ho, in tranapUntfng, are obliged to 
that tbeae delicate and essential 
be ai little aa po«nble diatarbed. 




► 8TUDY CHEMISTRY CHEAPLY, 

«Y JAUKI^ HERBERT COOKS. 

(RerHmtd from page 2 1 .) 

deaarib«d the inatnunent required by the 
i now remains to give directiODs for their 
ipnlstion, with a few experiments, in 
iie an insight into the general manage- 
enucal processes. As theee papers are 
!d as an introduction to the science, I 
10 fonber cxpUnatioD, than will suffioe 
e rationale of each expcrimont well un- 
for other information I refer the student 
td't » Elements of Chemistry," or to any 
r poUMwd work on the subject^ 

UAMPULATION. 

/Atf 9j)irit-lamp, tripod-atand, ^c. — 

l-lanp is used to give heat in erapora- 

lUtion. preparation of gases, and in all 

rtiment^ where a moderate heat is to be 

t nntities of any subatance ; also, 

1 ' nding and working glass tubes, 

fliuk CT eraporiting vessel beiu^ placed 

the lamp is adjustcrd by means of the 

, to a height beneath it, pruportion- 

c of beat mtended to be applied ; — 



^M 




when the tin ryltnder is employed, care must be 
taken to leave sufficient space between it anil the 
bottom of the vessel, to allow of a free ascent of the 
heated air, otherwise the draught will be stopped, 
and the process much impeded. 

f7«e qfjloikt, Sfc. — Flasks ore osed for distilla- 
tion, preparation of gasea, solution, digestion, &c. 
For the dtsrillation of water or alcohol, take a clean 
flask and lit a cork to it, bore a hole through it 
with n red-hot wirr, oad enlarge it until it will ad- 
mit the shorter end of the bent tube, which is jwased 
just through it ; four or five ounces of the liquid is 
then poured into the flask, which is placed on the 
trii>od ; the other end of the tube is paaaed (with- 
out a cork) into another flask placed in a Tsssel of 
cold water ; the liquid in the flaak is now made to 
boil by the application of the lamp, and the steam 
coming through the tube into the receiver, Is thera 
condensed, by the cold water in the veasel in which 
it is placed ; this water sboold be withdrawn by 
means of a syphon, when it gets warm, and the 
vessel refilled with cold water. In distilling acids 
and other fluids, whose vapours would corrode the 
cork, make a little plaster of Puris into a stilT paste 
with water, and spply it to the end of the tube, in- 
stead of u. cork, fitting it to the neck of the flaak aa 
before ; the neck of the receiver should also be par- 
tially obatrooted with tow, as the nneondensed acid 
fumes are very disagreeohle, and even dangerous, if 
allowed to escape into the apartment. 

For the preparation of gases, the bent tube is 
fitted by a cork, to the tiask containing the mate- 
rials from which the gas is to be extricated, the 
other end of it being pasaed under the arch in the 
shelf of the pneumatic trough, which must be filled 
with water ; the phial intended to receive the gaf. 
being oorapletely filled with water so as to exclude 
all Btmospherir air, dose the neck with the finger 
and invert ou the shelf of the troogh, over the hole 
in the bottom of it, the gas then ascends into the 
bottle, displacing the water ; the portion of gas that 
cornea over first should not be collected, aa it is 
always contaminated with atmospheric air; when 
the phial is fall of gas, remove it from the shelf and 
cork it onder water, immediately replacing it with 
another, previously filled vriih water : the jar of 
gas ahuuld be preserved until wanted, inverted, vrith 
its neck under vreter, in a wine-glas* or gallipot. 
Gaaea prepared withoot beat are collected In the 
same way ; chlorine roust be collected over warm 
water, aa it is absorbed in large qoantities by cold 
water. Some gases may also be collected by dig- 
phetment, which consists in conveying the gas, if 
heavier than air, by a bent tube, to the bottom of 
the receiver, so that it may gradually drive out the 
air ; if the gas is lighter than air, the receiver must 
be inverted over the bottle in which the gas Is 
generated, and it is conveyed by a atraigfat tube to 
the Qpper part of the receiver ; this methotl may 
be adopted vrith those gases that are absorbed or 
decomposed by water. 

Some BubstaDces that are insoluble, or nearly so, 
in cold water, dissolve readily when boiled, or 
heated in it ; sometimes a snbstance is heated in a 
liquid for the purpose of extracting some soluble 
matter from it, which is termed digestion ; both 
these processes are carried on in a flask, vrith the 
aid of the tripod and <tpirit-lamp. 

Vte tif tmxporating dixhn. — When a substance 
has been dissolved in a liquid, in order to recover 
it, we have recourse to evaporation, which is con- 
tinued ^ either until cryBtalUiatioa takes place on 



dl^ 



46 



MAGAZINE OF SCIENCE. 



}liiig. or until the substance i« \rti dry in the 
e1 : for cryi-talluin?, tbc general nile i?, to cun- 
tinue the evapnratioo until a pellicle ar Rkin formi 
the surface of tbe liquid, when the Tc&sel should 
»e removed and set aiide, that crjstal* may form, 
which will geaeraHy take place in a few hours. 

fjKr of tfti gloMMM. — A teal '« any known chemi- 
cal body, which, when mixed with an onknown 
aabirtance, produces appearonceB, which enables as 
to judge of ita nature and propertiea: thus, if s 
solution of ferrocy&nate of potaaa, when added to a 
mineral water pnjdnces a blue color, we know that 
the water, under rxaminahon, contains iron, be- 
eaoBe a bine compound U olwaye formed when this 
•alt ia added to a aolutioa containing iron ; the 
cobsUoce formed is termed a precipitate ; its form 
and general appearance are aluo to be coniidered, 
as the color aloue is not always sufficient to dcter- 
nune Its nature ; sometimes a precipitate baa to 
undergo a more parlicuUr examination, as to its 
solubility, &c., in which caie, we bare recourae to 
filtration, to separate It from the liquid io which it 
was formed. Wine-glasses, \c. used for testing, 
or precipitation, should be quite plain and free from 
cutting and ornament. 

Filtration. — In order to collect a precipitate, to 
flree a liquid from dirt or impunity, it most be made 
to paaa through a filter uf porous paper, which re- 
tains all insoluble matter, and renders the liquid 
dear, 'after passing through it ; to make s ftlter, 
take a piece of filtering paper, five or six inches 
■qaare, which will be Urge cnongh for the funnel 
U-forc described, smd fold the opiwsite comers to- 
gether twice, so as to form a conical bag or cup, 
which is to be placed in the funnel ; the funnel 
may be supporteil on the tripod, placing a vessel 
nndemcalh, to catch the filtered Uquor. A preci- 
pitate may be remorcd from the filter by means of s 
knife. 

f/»e (if the blowpipe, — The blowpipe is one of 
the roost useful instruments the chemist possesses, 
as it exerts sll the effects of the most powerful fur- 
naces on a small scale, and thus ensblea bim to per- 
form qualitative analyses, and go through many 
other experimentit, that could not otherwise br ef- 
fected without considerable expense end trouble ; it 
is also of great use in the laboratory, in bending 
and working glasa tubes ; it is used to convey a 
csonatant current of air through the flame of a lamp. 
whereby it is converted into a horizontal jet of 
flame, and an intense heat is excited near the point 
of it : to keep up a continual blast is generally a 
matter of no small difficulty to the beginner ; be 
may, however, overcome it by attending to, and 
practising the followini; directions. First — Breathe 
freely tfaroueh the nostrils, keeping the lips (-lo!<ed. 
Second—- Pill the chuektt with air, breathing as be- 
fore. Third-^lntroduoe the moath-piece of tlie 
blowpipe between tbe lips, nnd force the air from 
the mouth, by the action of the muscle of the 
dieeks, supplying air from the the lungs as the 
dieeks become empty ; all this may be soon &c- 
compUihed by a little practice ; llie student shnuld 
avoid blowing too hard, which is a common fault 
in begionerv, as very little more force is required 
than will suffice to bring tbe flame of the lamp into 
a horiioncal positioa. 

To bend a glass tube, bring the part to be bent 
gradually into tbe blowpipe-flame, and keep it con. 
stoutly lumiog round, nntil it is at a uniform red 
beat all round ; then bend it a little with the haods ; 
apply the heat to the adjoining parts of the tube, in 



like msniMr. and bend it again, repeating Uiis oper. 
Btiou until the bend has arrived at thr reqairrd 
angle: by tliese means, you itis^ v...:. . ^^^ 
round bend, free from wrinkles, wli ^s 

efl"er(ed if you bent it at once ; coru - ikm 

not to remove it from the flame too •<>)> lU . nr it 
will be very brittle and liable to criiik. inrrw Jifdi, 
when heated; many kinds of elass, when hronglLl 
into the blue inner part o{ the flame, receive « per- 
manent bUck stain ttota. the redoctinn to ihe me- 
tallic state of the oxide of lead they contain : this 
may be avoided by kwpiug it near t' ■■• ■'■>■■» • f tbs 
yellow part of the tlsme. In ordn i^lh 

hands at liberty during blowpipe \ ttw 

jet-pipe of the btoHpi^ic may be pa»>Fd Ifarondk a 
small staple of wire. 6ied iu the top of a bloa of 
wood of tbe proper height for the lamp. 

It nisy be nseful to add a few words on tbe ofr 
ce&Hity of order and cleanliness in 0|>eratiof $ •!' 
buttles and other vessels should be cleaned sadjut 
in their proper places after an experiment, that OMf' 
may be ready for use when wnntcd again ; 
care should be taken when experimenting wnlh 
and other corrosive fluids, not to spill, or sailv 
any to run down the outside of the bottle \ no bottle 
or box should he suffered to remain without a pop- 
per label. An old tea tray should be placed on <k« 
tabic when operating, and will be fouiui very ascfiU 
to save it from tbe accidental apilUng of liquid 
and the wear and tear that always accompaxiia 
chemical experiments. A due attention to the dk 
rections, will odd much to the coovcnienoe sntf 
comfort of the student, and will prevent much mot* 
tification and loss, from the failure of experimentA. 

In conclusion, I would advise the atudc ' 
no article, either of apparatus or msteriat- 
actuolly wants it; by this means he wili ... ..~ . 
great deal of unnecessary expense, for articles tbst 
he may seldom or never want; for this reasao«i 
have not given any list of chcmifats, &e. to 
vided, as is generally done in adentihc 
may, however, be necessary to state, Chat 
should be preserved in bottles with glasa stO| 
all other materials may be kept in comJDoa p 
well corked, or in pill boxes. 

(iSi be continued.) 

OBSERVATIONS ON BUGHT. 
Blight is a term generally misunderstoed, 
cially among those whom it more particuUrIf I 
cems. The knowing horticulturist wiU Cell 
" There is blight in the air to-day ;" and 
daya or weeks he will see the web of the 
or the yellow tail, or the ermine, on hu whilr^ 
hedge-rows ; or the caterpillars of the di 
head hawk moth on his potatoes; or tho<> 
terfliea on his cabbages ; and then be will 
a toss of his wise head, and utter, with 
quite in keeping, " I knetr there would h- 
this year ; 1 saw it coming in the air." rrrriar 
liowtrver, be may find a good many snails eitinf: 
woll-fniit ; or may, perchance, trrsd on two 
three great stag beetles while perfDrminr tbrir 
evening pcrambuUtion along his gravflU'd walks { 
and then, " he knew it would be either a blight or 
a sneg; but it's more of t sneg this year.** 
Further than this, the horticultorist has nut pr»k 
greased : webs and soft insects ore blights ; m 
and hard insects are snegs. Warm south- 
winds produce the first ; cold north-east windc-t 
lost ; and yet the saraa man would laugh in 
face if yott were to ssy serioasly. oa ■ cold 



MAGAZINE OF SCIENCE. 



47 



'* There will be a riae in the Tunds (o- 
un Bce it in tbc air." I maioUiu (hat 
urdljr be a grcftter semce performed to 
l«gmniltiinies, than by pointing out to 
pitnre and habits of their in8«ct enemies ; 
llaqB;bing at xa in the fint instance will 
I repaid by tbeir thanking as at last. 
loDfidcr, scparatRlj, tome of the insects 
^ the name of blight. We will, in the 
DC, uamioe the upple>trce. Cider ii an 
article of manufacture, as well aa con- 
in many of our counties ; and, con»e< 
tcTcr tends to inoreaae or diminith tlie 
jU to be deemed by the ffrower worth 
The apple-treo hu manj assaiUnta : 
are the wecriJ, the voollj loose or 
ight. and the moth. I will describe 
Uwse, and its mode of proceeding. 
J cramintng the hark of an apple-tree 
you wiU occuionalty find a pretty 
in the cnicka, which, directly on being 
I dead, and drops on the ground, 
will not, without great difficult, dis- 
account of the groat timilarity of ita 
mast, therefore, hont till yon find 
%Ib time, as soon u yoa lee him, place 
flow him, then touch him lightlr with a 
stick, and be will drop into your open 
own scheme for self-prescrvution will 
Now nil hira into a qoill, or pill. box. 
In home. Place him on a sheet of 
ler ; you will soon see his shajie — the 
bhed with a trtink, from which, on each 
I a feeler, bent at right-angles forward, 
r trunk altogether looks to be three- 
EC a trideut. The thorax and wing cases 
beaatifully mottled ; and an obliqne Uoe 
bting towards the suture or meeting of 
■cs, is much lighter colored, and gires 
MIb an appearance of having a letter V 
■Iked on its back. Its size altogether 
I than a bcmpseed. 

I first sanshiny day in March, these 
» their winter quarters, crawl up the 
long the twigs, perch themselrcs so as 
be full benefit of the sun's rays, and 
•elves with their legs and feet all over, 
all, juat in the same manner that a cat 
lace with her paw ; they then stretch 
at a time, cramped, no doubt, by the 
t ; they lift up their wing-cases, 
two large transparent wings, which, 
le as long af) the wing-cases, were 
>p and hidden under them, and then, 
cmseiTes into the air, they go roving 
ehards and gardens, tbeir little hearts 
r of frticdom, and love, and happiness. 
; before ea^ finds a suitable mate : no 
i objections ; and the nuptials are con- 
Now 1 will allow the gentleman weevil 
f in quest of new loves and conquests ; 
WU time 1 will observe the conduct of 

the female is ready for the important 
■Jtlng her eggs, the spring has con&i- 
lAcc«l. the apple-buds have burst, and 
Irhcs of blifflsom arc readily to be dts- 
The weevil soon finds oat these; and 
lloxsom cTcry way to her mind, com- 
V The beak, or trunk, before 

at iU extremity with short 



L 



tceth» or mandibles : with these, she gnaws a very 
minute hole into the calyx of tbc future blossom^ 
and cootinncs gnawing until her trunk is plunged 
in up to her eyes ; the trunk is then withdrawn, 
and the hole examintd with careful scrutiny by the 
introduc^tion of one of her feelers, or onttT prongs 
of her trident. If it seem to require any alttralion, 
the tnmk goes to work again, and again the feelers ; 
at last, being fully satisfied that the work is well 
accomplished, she turns about, and standing with 
the extremity of her sbdomcn over the bole, thrusts 
into it lier long ovipositor, an instnimetit composed 
of a set of tubes retractible one within the olhcrf 
and deposits a single egg (never more) in the very 
centre of the fiitore flower. Another czamioatitm 
with her feelers now takes place ; and when she la 
thoroughly satisfied that all is right, away she Ales 
to perform tbc same operation again and again^ 
never tiring while she has an egg to lay. 

The bud continues to grow like the other bods ; 
the little perforation becomes invisible. By anil by 
the egg burets, and out comes a little white maggoty 
with neither legs nor wings, which, directly It ia 
hatched, begins to devour the young and teadw 
stamens : next to these, the style is atUcked, and 
eaten down to the fruit, the upper part of which is 
qnickly consumed ; the maggot a then full fed ; 
it casts its skin, becomes a chrysalis, and lays per- 
fectly still. Up to this time the blossom has con- 
tinued healthy, no trace of the enemy being to be 
discovered without ; but when the neighbouring 
blossoms are expanding their petals to the genial 
breath of spring, those of the mutilated bud remain 
closed, and retain the arched balloon-like appear^ 
once of a bud about to burst. For a few days they 
presem) their lovely pink color ; and tbea, by 
degrees, fade to dingy brown. lathis state they 
remain until the other apples are well knit ; and 
then the damaged blossoms, by their decided con* 
trost, appear very conspicuous. On opening tlieso 
brown, or rsthar nist-colored blossoms, about the 
lOth to the 15th of June, tbe chrysalis will be found 
to have changed to a perfect beetle, similar to ita 
parent above described, which, hod it been left to 
itself, would, in a few days, have eaten its way 
throagh the weather-beaten case of dry petals, and 
left its prison-house, flying about to take its plea- 
sttre, until the chilly winds of autumn should drira 
it to ita winter habitation under the bark : and in 
the next spring, the wliole round of oporstions, 
through which we hare watched its parent and 
itself, would be performed with the same unvarying 
unerring instinct. 

The cloudy misty east wind, in which our farmera 
and gardeners see the blight, ia tbe very weather 
of all least favourable to the propagation and in- 
crease of these weevils. The fine, clear, raany 
days of March and April are the moat fkvoorable 
to them. The tomtits, sparrows, boUfinches, and 
other birds, which, at this time of year, more par- 
ticularly frequent orchards and gardens, and which, 
also, at this time of year, are persecuted vdth re- 
lentless hostility by Uie former and gardener, live, 
during these months, solely on these weerila, and 
similsr tittle insects ; and, consequently, are the 
only check ou their increase which we possess: so 
that, in the first investigation of blight, wc see bow 
a little prejudice, superstition, and ignorance, tend 
to increase the injury they dread. 



48 



MAGAZINE OF SCIENCE. 



MEMORANDA. 

The Pcrit Telegraph*. — There ire in Pari* live 
tcle^nphs, vie, the centrtl telegraph in the Kne 
lie riJoircraiti-, which is about to be tranaferreil to 
the Miniiilry of the Interior ; the telegraph at the 
Ministry of Marine, which corresponds with the 
line of Brest ; the telegraph on the church of 
St. EustAche, for Uie line of Ulle; and the two 
uj>on the toven of St. Sulpice, onn of which (the 
north) corresponds with the line of Strueburg, luid 
tlic other (the south) with Lyons and Italy. At 
the oentnl station accounts are recciTed from 
Calais in three mioutes, l)y a line of 27 telegraphs ; 
from Lille in two minutfn, hv 22 telegrapha ; from 
Strssburg in six minutes, by 46 tele^phi ; from 
LyonK in eight minutes, by 50 telegraphs ; and 
from Brest in eight minntes, by 80 telegrapbi. 

Oh Making Bone Gbte. — The French have of 
late years made a considerable quantity of glue 
frova bones, which they consider as BDperior to the 
ordinary glue made from the skins of animala. 

For the pnrpOAe of making this gtun, thry use 
the refuse boue of the table knife-makers, and the 
skulls of oxeo, from which the teeth hare been ex- 
tracted. These materials ore soaked for aboat a 
week in water rendered very sour by the addition of 
a liltJe spirit of salt ; in which time they become 
quite flexible, and may be bent with ease. Being 
taken out of the acid, boiling water is ponred on 
the bones, or rather glue, to separate any %ttmt, 
and also the acid that adheres to it. The pieces of 
glue are then wiped, wsfihrd in cold water, and 
dried in the shade. S^'hen this glue is to be nsed, it 
is boiled in water to a proper consistence. 

Mineral Tallow. — This rare substance, which 
was discovered in Finland, in 1730, has lately been 
found in a bog on the borders of Uwh-fyne, in 
Scotland. It bos the color and feci of tuUow, and 
is tasteless. It melts at 118 degrees, and boils at 
290 degrees. When melted, it is transparent and 
Golorlss ; on cooling, it becomes spongy and white, 
though not so as at tint. It is insoluble in water ; 
bat soluble in alcohol, oil of turpentine, olive oil, 
and naphtha, while these liquids are hot, bat it is 
predpiiated again when they cool. Its specific 
gravity, in Its DftCural atate, is 0,607H ; bnt the 
Callow is full of air babbles ; and after fusion, which 
disengagu the air, the specific gravity is 0,9H3, 
which is rather higher than that of tallow. It does 
not combine with alkalivs, nor form soap. Tlius it 
differs from every clafs of bodies known — from the 
fixed oils in not forming soap ; aud from the vola- 
tile oils and httnmcns, in being tasteless and desti- 
tute of smell. iLtt Tobtility and combustibility are 
equal tu those of any volatile oil or naphtha.— £<f/ii- 
hurgh rhilosophical Journal. 

EjTjierimenU on Human Hair. — M. VaagneUn, 
the celebrated French chemist, discovered from 
acme experiments wliich ho made, that black hair 
is formed of nine difiTereut substances, viz. animal 
nutter, a. white concrete oil, anotlter greeniah grey, 
one which is very abundant, iron, some particles of 
oxide of manganese, a phosphate of lime, carbonate 
of Umc, silcx. and a considerable quantity of sul- 
phur. Red hair contains red oil in place of a 
greenish black kind, and white, or very Light hair, 
difleri from all the olhcro. as the oil is nearly color- 
less, aud it contaiiu some phosphate of magneaia, 
which is not found m the others. 

Ga»from PyrtiUpneonx Acid, — U has lately been 



diftcovered thst when vcood arid ts mi 
through an Iron tnbe heated to ignil 
Nciil allowed (o enter the tube by di 
aucces«ian, gas of a very excelleot. 
talned. This fact wai Arst obser 
of this city, whilst pursuing ex| 
purification of pyroU^neoos acid. — 1 

Steam Enginet. — The value of the at 
to this country may be estimated from 
which show that the number of steam. 
England represent the power of 
which ia equal to that of 1.920, 
being, tn fact, managed by 36,000! 
actually to the power of our populatioii 
men. This Is wholly independent of I 
railroad locomotive engines. 

Cotuffarattre Magnitude of Plamet*.^ 
the earth to be 12 inches in diameter, tb 
is 4 ft. 5 in. Saturn 10 feet, Jupiter II 
diameter. Therest of the planets, nhich 
than the earth, bear the following relative ■ 
Vcnna 1 If in., Mars Gi in.. Mercury 4l 
3( in.. Jono 2| in., Ceret 1^ in., and ▼ 
in. in diameter. The comparative dianqi 
sun is 111 ft. B in. and the moon 5| incl 

Horticulture. — D. Powel, Esq., of 
EsMX, recommends the following inetl 
caring sdons when fitted to the stock i] 
spread the grafting wax in a melted atatc 
shMta of moderately thin brown paper, 
cold cut It into slips about } of an inch 
one of these slips with the breath, and bi| 
the atock and acion, pressing it gently 
hand, when it will be found to adhere tt 
totally to exclude both nir and moisture, 
may be prepared by melting U^ther lib 
lib. of resin, ^Ib. of beet' -wax, i^Ib. of 
and ^Ib. of turpentine. By placing the 
in an earthen pan over boiling water, it ni) 
in such a state of fluidity as to be easily « 
the paper with a brush. — TYtiuartiOHM % 
dun Horticultural Society. 

Fishing through the fee. — At Hudsoi^ 
rivers near the sea. and in lakes of a 
than ten or twelve feet, fishes are cai^ 
winter, by catting boles through the 
the water, and putting lines and hooka 
But in taking them with nets, thry cat 
in a straight line the length of the net. 
the net with a stick fastened to the bead 
hole to hole, till it reaches the utmost 
what fishes come to these holes for air, an 
in the net ; and these fish, at «oon 
brought into the open air, are inatanllj 
sUiT as stock-fish. 

A Sauing Mill in 159S.— Between R« 
Alatat, near Dantzyke, is a mill which, il 
ion is very rare ; it is driven by a river, 
out the help of hands saweth boords, one 
iron wheele, which doth not only drew I 
booketb in and tumelh the boonla to 
Moryaon'a TfateU, 1593. 

The Navigation qf the Alhf^*-^ '•■' «'- 
1838 ridiculed as an impoasib 
accomplished; in 1840 vesaelF 
Britain and the United Statea as 
twecn London and Leith ; and in 
Utcd thst there will be 42 steamei*; 
burden of 56,260 tons, employed fai 
alone. — Mechanic*' Attfuiimck. 






l.i»!«»«j>i — I'lUi'-fJ '■) 1>. f ^A.■i^.n, *, \MLi'.c lljtii l.-iiie, Mi'c KatI — Pu'jluijpJ '•) W BauiAiy, II, l*^»l«a 



THE 



AGAZINE OF SCIENCE, 

^nti Retool of ^rtsE. 




50 



MAGAZINE OF SCIENCE. 



DAVENPORT'S ELECTRO-MAGNETIC 
ENGINE. 

Trk property of electro-ma|cnelism, lo product ft 
strong and rapid rotAtory mmtun of a iiroperK-irrin- 
slrui-'icd a|)|iBijUuj^, t* thuttgtit capsblt: of afforduig 
a tnoviii^ puwrr which may, wlit^ii brought luperfcv- 
tkrtii, siipcrwdc U)C steam rngiae tUclf. both in tco- 
Quaiy, CO m pact n CSS, and facility of manageiuetit. 
'['hut «nch will evtrntuslly be the case in rxtremely 
l^'t-obuble. The models hitherto constructed have 
alrcjidy nccomplitbed much ; Professor Jacobi has 
workrd by this meatiK a ?iix>oarrd nutter nith cou- 
sidemble speed. Mr. Sturgeoa expresses his opinion 
of the ca|wbllily of applying tbe power to locomolive 
carriages on common roads ; and we have ourselves 
■een its lacceuful application to the grinding of 
cofTee, the turning of foot-lathes, and other light 
marbines. The attention of the scientific world was 
first turned to Uiis important subject by tl)e electro- 
motive machiitc of Mr. Davenport, an American, 
who obtjiined n patent for hi:^ invention in the year 
1837* This patent, however, «\aiU hut littlr, be. 
cause it is so esitreniely easy to modify the apparatus 
into a ditfereiic form, and in reality to give it greater 
strength ; thus numerouii uiachineAof the same kind 
Lave been invented, and although Mr. Davenport's 
is therefore disased, yetlieing the 6r»t of any mag- 
nitude, and that which first colled forth the inven- 
tiODS of others, it is proper to take notice of it, 
which wu do in the words of the specificalion, tjiken 
irum the" Franklin Jouraal,'' of November, 1837; — 

"Tlie innchinc for npplyingthe power ofmngnct- 
isro, and riectro-magnrtism, is described as follows: 
The frame AAA may be made of s circular, or any 
other figure, divided into two or more platforms, U 
and C; upon which llie apparatus rest8, and of a 
flise and vtrength adapted for the purf)otie intended. 
There arc two conductors, II and I, one from the cop- 
per, and one from Llie zinc end of any galvanic Iwttery 
leadti>(; to. and in contact with copper plates. K unJ 
Xj, pliii'ed upon the lower platform. These pliitr«, 
or conductors, are made in tlie form of a segment 
of a circle, corresponding in number with the arti- 
ficial tnAgnetK hrreinafler dnscribed ; they are placed 
around the sliaft. detiu'hcd from one another and 
from the fboft, having a conductor, leading ftnm Uie 
cupper-pUtt of the battery, to one of the i^aid plates 
on the lower piritform, and another conductnr Icrut- 
iitg from ibr zinc-plate of the batter]^ and so on 
ftlternately around the circle. 

" The gaUauic msgnets, M, N, O, P, are con- 
structed of arms, or pieces, of j>u(t iron, in tbeihnpc 
of a Atmigbt bar, horse-ahoe, or any other figure, 
wound with copper wire, tirat iniulatcd with Mlk 
coils ; these arms project around it horuiootally frnm 
the centre of a vertical shaft R, turning on u pivut, 
or ]>oint, in the lower platform ; the siud cupprr 
wires extending from the arms parallel, or nearly 
so, with the abaft down to the copper-plates, K and 
L. and in contact with them. 

'*Th6 ortiticial magneta S, T. ore mode of steel, 
and in the osu:d manner. They roay he of any 
number, and degree of strength, and fixed on the 
upper plHtfurni, being segments of nearly the laine 
circle as this platform ; or if galvanic magnets are 
used, (which may be done,} they may be made in 
Ihe form of a crescent or horse-shoe, with their poles 
pointing to the shaft. 

** Having arroDgcd these artificial magnets, on tbo 
lop of the u])pcr circulitr pUtform, there will he a 
corr espobding number of magnetic poles — the north 



marked D, and the south pole E. Now we wfll 
suppose the machine to be in » quiescent UmU 
gulvanie magnet O. being opposite the south pott tt 
the artJtii^al magnets, the galvanic-maguet P. wfll 
of cour*e be opposite the south pole E, and the gtl' 
vsnic uisgnets. M and N will be opposite each otbct. 
betweeu Ute poles just mcntiuned. 

"There being a corrrspondingmftnber olcoppa 
plates, or conductors, placed below tb»' krufidol 
magnets around the shaft, hut i\'- < it, 

as well as from each other, with «)■ : ir 

the galvHnic msgneln to these platea. and in 
with them, as before described, these vires » 
stand in the same position, in relation to the coppai 
plates, that the galvanic magnets »taud to the artA* 
rial niagnetf, but in contact with tlic pUtca. 

" Now in order to put ibe macbioeln mot^va. 
galvanic magnet M, being charged by the galvaldi 
current passing from the copper plate of the btf« 
tery, along the conductors and wires, becomes • 
north pole, whilst, at the same time, the umgnet K 
is charged by the galvanic current poe.&ing from tW 
line plate of the battery, and becuinrs a sooth p9^ 
of course the south pole of the galvanic ma^nCt. 
will attract the nortli pule of the galvanic 
and will move it a (|uarter of o circle ; the 
pole of the galvanic magnet N, being at ihtt 
dme attracted by the north pole D, causes 
magnet M. alrio, to perform a quarter of a 
the momentum of the galvanic arms will carry 
past the centres of tlie poles D and E, at 
time the several wirca from the galvanic 
will have changed their poftitious iu relation 
copper plates, or conductors : — Kor ins 
north pole M, having now become a south 
reason of its wires being brought in cooi 
the conductors of the sine plate, and N ha' 
like manner, become a north pole, ita wine 
changed its position from the sine plate to thtj 
per plate, the poles of the galvanic magnets 
course, now repelled by tiie [>oles that 
tracted them ; and in this manner the opri 
continued, producing a rotatory motion in the 
which motion is conveyed to machinery* fat 
purpose of propelling the same.*' 



DECOMPOSITION OF WATBB 
GALVANISM. 

Trk chemical powers of the voltaic pil«, or 
hnttcry, were lirvt observed in reii;Mrd lo the 
position of water by Messrs. Carlisle and Ni* 
in the year 1800. These were thrr, 
investigatrd in 1803, by lliainger m. 
in 1807, Sir H. Davy commuuicntiti ui 
lecture " On suuieChemicfll Agencies uf Elect 
tothr Royal Society, in wbidi the cit-ctro- 
powers of the pile were eluborately exsminf 
which (ornied the groutiu work of thr brillij 
cuvcries to which he was soon ofterwards lead 
prosecution and eitension of bis researches, 
were, however, many imiKirtant p! 
especially those connected with lb 
electricity by chemical action, and ••... ^■. 
of eleclru-cberoirnl decomposition, which 
Davy and others, who8<; researches have enli| 
thin dillicult department of tleclrical science, 
lefl unexplored, or insufficiently and unsatii 
evplained ; these have lately engaged the atl 
of Professor Furaday, and his " KipcnmenI 
searches in Electricity," published first in 
cession of papers in the " Transactions of the 



maga;:ine of sciknce. 



51 



lately in « diktinct volume, contnn the 
Ubors in reCercmce to ibis branch of 

I 

i eondoctiDg vim from the extremes 
ic pile or bnttery, ire brought near to 
^ rrrtnin liquids, each for infUnce is 
Uine €Otution» . or in other words, when 
I make part of the electric circuit, lo 
frent of the electricity pMs«i through 
ire d^eompoaed : thai )«, they yield up 
its Bi obedience to certain laws; water 
b rMolved iiitt> hydroffen and ori/ffen. 
■a I!m elements appear at the potfs or 
^t indiscrttninately, or inditferctitly. 
ka is devt^loped at the anodf, or xurface 
ff electricity cnlen the water and the 
I the etttHthht or larfaee by which the 
|bt leaves the body under decomposition. 
the manner in nliich water is decnro- 
^ , ,.f,,i,.. f the optnition with neatness, 
t(ty. many coutrivancea tnay 
1 ' ing will illnstrate tlie subject 

rli two plates or strips of platina foil, 
llh the ends of the voltaic battery, be 
* to each other in a Rlaaa of water, a 
^ frill issue from each, which, in an 
(Dilar to rither of those represented In 
I be collected, and submitted to rxanii- 

kvaenls the glass of water, and the two 
!>•, each incJosrd in a ((lasR tube. The 
Ubcfatfd, will asL'end the tubes, and 
in theoi. Fig. 2 rcpreKent* ■ mor*: 
itiLS but one ui which t)ie librrnted 
Itained in the «iiine tube. Itcon- 
Ithed gla^s, wtlh a fuot tu it, and 
eaoh aide. In the necks are fixed, 
the two wires, the outer ends of them 
^ with mercury cups, and the inner 
I op, made to pass through a cork, 
'an inch or two abOTo it. The glaM 
U to catch the gas is fixed over the 
y - - -■^ntation of ^ far superior 
I :c of which will be readily 

] : _ utily that the two glass tubes 
ft hra!i» plate which 6tJi ou to the top 
tower glaM. 

i»baerved, that twice the rjnantitr of ga« 

ie negative |iole, or calliode of the water, 

I with that at the positive pole, or at the 

\ water. When a single tube is used, 

bul lo contain n niiitnre of oiygen aud 

■Of, Ui ,the pniporlion of two volumns 

pr 10 one v( the latter. If a lighted 

paght to the montb of the tabn, thn 

^ explode and disappear, rp-produciog 

^tiry of water decomposed. In using 

ftbed apparatus, it will be iteen that twa 

i_ J jj^j gjj^ voluron of oiygen 

<1 m the tubes invi-rlwl over 

-- ; , .live wires. L'pon the approach 

ir byflru((c;o gas will burn quietly with 

flame ; and the nxjgcn may be rc- 

lerving into it the gloning wick of 

dft. taper, which will mstanlly kindle 



OF THE ATMOSPHERE. 

ipts have been made to ascertAin the 
the atmofphcre is extended ill 
These commenced soon after it 



^iftfa. These 



was diacoverad, by means of the Torrieellian tube, 
that air is o j^ravitatitif: ituh^ttnnce. Tint* ir aUo 
became known, that a column of air, whose ba«e is 
a square inch, and the ht^ight that of the «hoI« 
atinuHphere, weighs ir> pounds ; and that the weight 
of it is to that of mercury at 1 to 10,800 : whence 
it follows, that if the weight of the atmosphere he 
sufficient to raise a column of mercur}' to the height 
of 30 inches, the height of the aerinl column must 
be 10,)400 times aa much, and conseqaently a little 
more than five mllfj hi^b. 

It was not, however, at any time supposed, that 
this calculation could be just ; for, oa tbe oir is an 
elastic fluid, the U]>pcr parts must expand to an 
immenae bulk, and thus render the calculation 
above related e.\cecdlngly erroneo\i9. By experi- 
ments made in different countrieiy it bos been 
found, that the spaces which any portion lakes up, 
arc reciprocally proportional to the weights with 
which it is compressed. Aliowaoces were tn be 
made in calcolatiug the height of the atmosphere. 
If we suppose the height of the whole divided into 
innumerable equal partii, the density of each part of 
which is aa its quantity ; and the weight of tlie whole 
incumbeut atiuotipherc being alao aa its quantity ; 
it is evident, that the weight of the incumbi:nt air 
ie everywhere as the quaattty containpd in the snb- 
juccnt part ; which innkea a difFcrencc hftwf;^ the 
weightu of each two contiguous parts of air. By a 
theorem in geometry, where the difTerences of rosg- 
nitudea are geometrically in proportion to the mag- 
nitudes, these magnitudes are tn Ronlinual orilh- 
metical progression ; therefore, if, accrording to tbe 
Bupposttion, the altitude of the air, by the nddittnn 
of new parts into which it is divided, do rontmually 
inoreaac in arithmetical proportion, its don»iiy will 
be diminished, or (whinh is the aam? thing, \ln 
gravity decrtmsedj in continual geometrical projKrr- 
tion. 

It is DOW easy, froni such a series, by making 
two or three bommetrical observjitions, and deter- 
mining tlie deofHty of the atmosphere at two or 
three different ktatiuiiH, tu determine iti absolute 
height, or iti rarity at any afi.4igiiable height. Cal- 
culations accordingly were made upon this plan; 
but it haxing been found that the barometrical 
observation by no mcanfi correapoaded with the 
density which, by other experiments, the air ought 
to have bad, it was suspected that the upper parta 
of the spherical regions were not suhjix-t to the 
aame laws with the lower on<^. rhiloiophrri. had 
recourse to another method for determining the 
altitude of the atroofphere, viz., by a calculation of 
the height from which the light of the sun ia 
refracted, so as to become visible to us before he 
himself is seen in the heavens. By this method it 
was determined, that at the height of if* miles the 
atmosphere had no power of refraction ; and con- 
aequently beyond (hat ditttaiire wia either a mere 
vacuum, or the octt thing to it, and not to be re- 
garded. This theory aoon became very generally 
received, and the height of the atmosphere was 
spoken of as familiarly aa that of a mountain, and 
reckoned to be as well ascertained, if not more so, 
than the heights of moat mnuntaina are. Very 
great objeclioos, however, which hove never yet 
been removed, arise from the appearanct; of some 
meteoiY, like large globes of fire, arc not unfreqoently 
to be seen at vast hcighta above the earth. A Terj 
rrmarkahic one of this kind was observed by 
Dr. Hallry, in the month of March, 1719, the 
altitude of which he computed to have been between 



MAGAZINE OF SCIEN< 



69 lad 73i Englinh milrs ; its dinmft^r 38(H) jnrd*. 
or upTnffls of n mile •nd « U'llf; nnJ itn vrl.wity 
■bout :i50 milr* in a minotc. Othcri^. (iDparenil/ 
of the ftmv kiitil, but whose eltilude and vwlooity 
were etill gmitrr, Jiiive hecn ohicrvrd ; particuUfly 
that renntrkiiblp one. Augtut iHlh, 1783. whose 
distAmrc ftotn tl.<» rirOi could not be lew (Kin 
go toilf*. anil its dmmrtcr noi Km than iUc farmer ; 
at Ilie saint- lime that its velocity was ctruiiily not 
le» thao a thuusaitd uiilee in a QiiDute. Firc-ballc, 
ill N)ipesranc« «tmilar to ihfse, though T&Blly infe- 
rior iu aize, have been sometimes obaencd at the 
surface of the earth. Of tJiis hind Dr. Pricitley 
mentions one seen on board the Montague, ibe ■lih 
of NoTembcr, 17t9, which appeared as bi; M a 
Wkc iiiilUtor.e, and broke with a violent explosion. 
From flii»logiL'ftl rca*onin(j, it seems very proha- 
ble, that tiie meteom nhich appear at such threat 
heighU in the air are not essentially different from 
those which, like the flre-baU just mentioned, are 
met with on the surface of the earth. The per- 
plexing circumsUnces with rej^ard to the former 
Are, that ut the great hrichts above mentioned, the 
atmufejihere ought not to have any dcDfeily suflScient 
to support flame, or to propagate sound ; yet these 
meteors are commonly succeeded by one or more 
eiplo<>ions — oay, arc sometimes mid to be accom- 
panied with a Liesing noise as they paas over our 
head*.- Tlie meteor of 1719 was not only very 
bright , insninurh that, for a ihort =pace, it turned 
night into day. biil was attendwl with an explosion 
bnitd orer all the inland of Britaia, occaaiouing a 
TJolunt eancuanion in the atmosphere, and seeming 
tOhhakc the earth it»clf. That of Kb^alw, though 
much hightr than the former, waa succeeded by 
ezpIosioDs, and, according to the tejitimony of 
sereral people, a hissing noise was heard as it 
pasiSL-d. Dr. Hallcy ockDOwledged that he was 
unable to rcranrile these circumstancea with the 
receive*! theory of the height of the stoioapberc ; 
as, in the rccions in which this meteor moved, the 
air ought to have Ixeii 30l».,*VnO limes more rare 
than wh.tL we breatht-. and the next thing to a per- 
fect vacuum. 

lo the meteor of 1783, the difficulty is atitl 
l^^ter, as it sppenr* lo have been 20 miles farlhcr 
np in the air. Dr. Hnlley offers a conjecture, 
indce>l. that the roAt magnitudes of such bodies 
icigt.t comp^nMte fur the thinnes^ of the medium 
in which ihcy nmved. ^Tiether or not this was 
the case cannot indeed be ascertained, as we have 
lo few data to go upon ; but the ({reatest difficulty 
is to account for the brightucw of Uie light. 
Appearances of thin kind are, indeed, with great 
probability, attributed to electricity, but the diffi- 
culty is not thus removed. 

It appears that the ubsoiute height of the atmo- 
sphere is not yet determmcd. The beginning and 
ending of twilight indeed show, that tbc hcigiit at 
which the atmosphere l)eKin8 to refract tlie sun'a 
light, is about -14 or 43 English miles. But this 
nay not improbably be only llie height to which 
the aqueous vapors are carried ; for it cannot be 
ihouglit any nnreasonablc supposition, that U^ht is 
refracted only by mcen* c)f the aqueous vapor con- 
tained in the titinosphere -, and where this ceasea, 
it is still caj>rtblc of supporting the electric fire at 
least as bright and strong as at Ihp surface. That 
ft dof» extend much higher, is evident from the 
meteors already mentioned ; for all these ore un- 
doubtedly carrie«l along with the lUrroephere : 
otherwise, tliat of 17H3, which waa aeen for about 



a minotc, muit have been left 10*" 
westward, by Uie enith Ayinfi out 
annual coarse round the sun* 



COMBINED ZINCING AND TIN 



I 



A r*Ti!?rr hsf hwn jrai " 

Messrs, Summer and N • 

improvement in the proct 

vent it from rusting, and aI*o to oh 

veaienec of zincinf iron, which iin- 

muiished malleability. The invcotiui* i* "n w.. 

proveroenl o« one for ainring iron for which » 

patent was granted, in 1*37, Iw M. *^ 

aficctJication of their invention th* 

that having become proprietor* ti^ 

M. Sorfl** patent process, in carryii 

pracrical operation they found that i 

of sheet-iron is much impaired by giving tt « 

ing of line in the manner directed t»y M . Sofrij 

and that, iu consequence of this dim ""^ 

bility. such prepared sheet iron ' '• 

many cues, lo be applied to the pm jMi^r u. 

ing the roofs of houses, or to be otfaerwrlsv 

where it is required lo be grooved smiiir. 

any way suddenly Iwnl. Thi* im, 

gists in a process by which this diffi' 

nbitst the line is st the same time ao appln J " 

itg galvanic action on the iron to proun it Trew 

oiidation. Their mode of prorecding ii 

deacribcd : — " Wc take sheets of iriwi, and 

them with tin, or with an alloy of *• ' 

adopting m thi.s process the mode ui 
in the well-known raanufaclure of - 
of iron into tin plate. After having 
this operation, we submit U»o sheets oj 
prepared to a like process, with the mV ' 
sine for tin. or an alloy of tin ; the — 
forming which does not differ fn>iii tbr' 
prt)cei>)« known under the name of tiimiug- 
tho« treated, Ihe plates or sheet* of irun pi 
tlieir mnlleahility unimpaired, and may be 
otherwise worked as easily as before they 
oeived such coating — a result which appears 
due to tbe interposition of the coating 
between the sine and the iron, by wbKh 
pohitiun the chemical combit»ation ot the 
zinc is prevented, ^"hcre it ii not 
iiae pbtles of meUl of a larger si>« thim 
iihoetA of tin plate, we take that RAteritl' 
comes from the manufactories, and have 
to give to it a coating of line, to rrrp 
doea not require any particular ; 
the Utters patent granted to M- 
posed, sometimes to add a coating "T nu 
of the xinc. for the purpose of giving to thei 
mode n hrightrr appearance, and as an 
ment also iu culinary vessels ; but our pt 
tbe reverse of tiiiit, unJ the end attuned 
altogether different from that above pi 
at the same time, our process prodoer* a 
useful result. What we claim, < 
invention, and as an improvement 
M. Sorel, is the preserving the m 
iron, wliilst it is protected (ron 
gtthnnic action between it and the 
ner above set forth — namely, by tirdt tinnuic 
said iron in the ordinary way, and aftcrwardll 
giving thereto a coating of zinc above thr rio.* 



MAGAZINE OF SCIENCE 



5.1 



CTHUS. OR MOtTNTA-IN FLAX, 

M elude mineral lubstiincc, of ■ stlvm- 
Df gtrrnuli nAar; lu«tre gllininerinj^, of 
r Mlkf-n n|ip*MMin(.i:. ll h pnft enough to 
td hj the nnti, nnd mniJrtrrHbtjr rInHttc. 
loft and soEDfvrbat ffn-nsy ferl ; — sp«!dAc 
pot 9.100. This mtnrral ia naQolly ravt 
pacA in rucks oC serpentine, but it in found 
Ij ia the strata of irou ore, soinelimos 
f an inch in dinrr.f*ter. It ii found 
nut, Elb'i, und (Vomica : in Francr, 
and in the Diouiitiiin« of Arcadia ; 
parts of Great Brilnin, but pnrticn- 
Igrlesrn in Widea, and Aherdfcnsbire in 
Thr Tsrentaiae amianthai from Savoy 
bcautlfal. 

to the actioQ of tlie blow-pipe, the 
amianthua fuse* into an opaque aub- 
I di'ifiUra quickly in borax and micro- 
hot rrTcrveacex with carbonated »oda. 
nal amis hove a very feeble ai-tinn on 
It appears, from Uerifinan, tbatniusUc 
brda the meanit of dUs/rlvin^ this aub- 
Mb he effivted by tniiing equal parta of 
Mrbonated potash, anil charcoal, and 
1 for two Ilount, by which he obtained 
wai perfectly aoluble in uitro* muriatic 
parta of the Tarentai»e aroianthua 
BDording to Bergman, sulphated barytea 
OiMted time 6.9 : carbonnted magnflaU 
iae 3^ ; »ilu 64.0 ; uaide of iron 1.2. 
fllltty of man, tvro thouaaDd years aince, 
«tion of a peculiar kind of cloth 
ta of this trjitniordinnry mineral ; 
wonderful quality of beiug iocon- 
When the cloth became dirtied or 
usual to throw it into a bright Are ; 
thua burnt out, and the cloth pnri- 
d of a drizzling whiteness. Pliny 
bflen an eye witness to this opera* 
times of the Roman em|>ire^ 
aed at an enormous prire, for 
pping up the bodies of the dead. 
On the funeral pile ; the ashes of the 
M preaurred unmixed with those of 
Of the rciility of this practice there 
t a (toubt ; in 1702 a skull and other 
, together with a quantity of aebes, 
at Porta Nievia at Rome, which 
in amianthus doUi ; which intr- 
antiquity is now prrsen'cd in tlie 

y- 

nf burning the dead becoming dis- 

niaoufacture of amianthus cloth was 

and (he art was lost in Kurope. It ta 

rhe art ia slitl preserved in the 

employetl by the TarLara in 

T of the d(r;id. 

tampini, of Rome, published the 
of mjfnuf.ti;tnnng this ini:om- 
"he amianihua is to be firat laid 
tank for some time ; it is then to 
divided by tbe hands by gentle 
the rxtrancims earthy matters will 
ord and washed out. which, in tl.c 
t arrre to bind thu hltrrj logettirr. 
to be repeated several times by 
water, nnd opetiinit and squeezing 
the water runs otf quite clear, 
be left but long tlnx.like fibres, 
lo be laid in a sieve and dried iu the sun. 



It is then to be carded (or combed) on fery ftne 
cards, and the long filaments are to be steeped in 
oil to render them more flcsible. It !s then to I»e 
plnecd between the cnrd in such a manner thiit a 
portion of it may hang nut at the tides, 7*litt 
Rptnniug of it is performed by fiaing a atnall red 
with a little hook at the end on the same bench as 
the cards. The red is to be wound orer with white 
thread, which twisting about the thread plaa^l in 
contact with tbe amianthus, Uic Utter, by the 
assistance of the thumb and fore-finger of tbe 
operator, is wonnd up and twixtftl with it into one 
thread. A conCinuou$ thread being thus produced, 
it is carefully woven into clulb ; placed afterwards 
in a clear charcoal fire, both the oil and the tbread 
of linen or cotton that was combined with it in 
the spinning and weaving are consumed, and there 
remains a pure tissue of white amianthus. Thla 
method being, however, very tedious, another hai 
been recnmmended ; which is to place a quantity 
of flax on 8 distaff, and taking three or four fila- 
ments of tite amtanthuft between the fingerv, tbey 
may be easily mixed and twifited along with the 
flax. Tbe thread thus spun will be much stronger 
and more durable than that made by the obove- 
mentioned jprocesa ; the carding will alio be anne- 
ceisary, by which mauy of the filamenta are una- 
voidably broken. 

Tbe abort filaments that remain after the washing 
or carding of the atone, have been made into paper 
by the ordinary method of manufacturing that sub. 
stance, except that a larger portion of size is em- 
ployed. .\n it would be worth while to preserve 
documents of great Importance by writing on the 
amianrhus paper with an indelible ink, that wuutd 
also resist the effects of fire, the following ret^eipt 
baa been given for Ihnt purpose : — To one part of 
of sulphite of iron add two parts of alum, which 
having dissolved in hot water, add pearlaah as long 
as any precipitate takes place ; the mixture is nejit 
to be boiled, then Altered, and the precipitate well 
washed with wsrm water ; distilled vinegar is then 
to be nddrd to the precipitate, which wilt dissolve 
it. and form an indelible ink. .\mianthn8 paper 
being written upon with this preparation, the cha- 
racters will be preserred after combnation, of • 
brown color, and perfectly legible. 

Threads of the nmianthuf ore fometimea naed as 
perpetual wicks for lamps. Amianthus h frequently 
confounded witli the more flexible kinds of aabestos. 
By some writers the terms are used synonymously. 
Others divide tbe asbestos into scTcrol Tftrtcties. of 
which amianthua ia one. 

THE TIDES. 

Tnn periodic motions of the waters of tbe oe«n, 
rtn thp hypothesis of an rllipsoid nf rerolntioiis en- 
tirely covered by the eea, arc very far from accord- 
ing with ob8er\-Dtion. This arises from the vrry 
great irregularities in the surface of tbe earth, whieh 
is but psrtially covered by the sea. from the voriely 
in the deptlis of the ocean, the manner in which it 
is spread out on the earth, the position nnd inclina- 
tions of the shores, tbe currents, and the reststnnre 
the waters nii-et with : causes impo^nihle to esli- 
male. but which modify the oscilUlions of the great 
mass of tbe ocean. However, amidst all these 
irregnlaritjea, the ebb and flow of the sea maintain 
a ratio to tbe forces producing them sufficient to 
indicate their nature, and to veri^ the law of the 



54 



MAGAZINE OF SCIENCE. 



■ 



•Unction of the sun and moon on the »ea. Lb 
Ftace observes, that the inrehiigition of bucli rtlt- 
tiomi botwrc-n aiu»e and effect, is no lir>w uiefal in 
natural phil(U0[)hy than the direct Mlution of |>rn. 
blems, either to prove the existence of the caasest 
or to trace the taw* of their effcctt. Like the 
theory of probabOltieft. U is ■ bappr supplement to 
the ignorance and weaknea of ibc huoiLin miud. — 
Thoi the problem of the tides does not admit of a 
general solution. It is indeed nccesaAry to analyse 
the general phenomena whicli oiii^ht to mult from 
the attraction of the sun »nd moon, hut thette must 
be corrected in each particular caw by local obter- 
YationB modified by the extent and depth of the 
sea, and the (irculiar rirrnmBtancea of tiie place. 

Since (he ditttuxbing notion of the sun and moon 
can only biH!Ojne sensible in n very great extent of 
water, the t'licit'ic Occ4[i mast be one of the prin- 
oipal Boarces of our tides. But, in consetiuenre of 
the rotation of the earth, and the inertia nf the 
oecan, high water doe* not happen till some time 
after (he tztoon'a southing. Ttie tide raised in that 
world of wBten is transmitted to the Atlantic, from 
whli;:h sea it rooTca in a northerly direction along 
the coasts of Africa and Knrope, arrtvme later and 
later at each place. This crcat wave, however, is 
modified by the tide raised in iho Atlantii-, which 
ftDmetlmea combines with that from the Pacific in 
niaingchesea, and somecimea ia in opposition to it, 
no that the tides only rise in proportion to their 
difference. This vaat combined wave, reflected by 
the shoret of the Atluntic, extending nearly from 
pole to polt!, still roming northward, poars through 
the Iriih and Uritiah Chatincls into the North Sea, 
ao that the tidei in oar porta are modified by those 
of another hemisphere. Tfaas the theory of the 
tides in each port, both as to their height and the 
ttmeA at whidi they take place, is really a matter of 
ozperiment, and can only be i>erfect1y determioed 
by the mean of a very great number of obserratioos, 
including sevBral revolutions of the moon's nodes. 

The height to which the tidea rise is much greater 
in narrow channels than in the open sea, on account 
of the obstructions they meet with. The sea is so 
pent ap in the British Channel, that the tides some, 
times rise aa much as fifty feel at St. Malo, on the 
coast of France ; whereas, on the shores of some 
of the South Sea islands, near the centre of the 
Pacific, fbcy do not exceed one or two feet. The 
winds hare great influence on the height of the 
tides, according as they conspire with, or oppose 
them. But the actual effect of the wind in excit- 
ing the waves of the ocean extends very little below 
the snrfice. Even in the most violent storms, the 
water is probably cnlm at the depth of ninety or a 
hundred feet. TUir tidal wave of the ocean does 
not reach the Mediterranean uur the Baliic, partly 
from their poaitioa and partly from the narnjwneM 
of the Straits of Gibraltar and of the Categat, but 
it is. very pera^ptihle in the Re<l .Sea and in liud- 
aon'a Bay. In high latitudes, where the ocean is 
leas directly under tlie influence of the luminaries, 
the rise and fall of the su. is considerable, bo that, 
in alt probahitiiy. there is no tide at the poles, or 
only a small annual and monthly tide. The eb)) 
and flow of the sea arc perceptible in riverx to a 
*^ great distance from their eatuories. In the 
SCraiti of Pjiuxis, in the river of the Amazonn, 
more than five hundred miles from the sea, the 
tides are evident. It requires so many days for the 
khio to aacend this mighty stream, that the (rtum- 
iag tides meet a succession of those which arc 



coming ap ; »o that every possible ri 
at ioioe part or other of its flion-. k-.tI, 
nitude and time. It rrqui;e« - 
of wntcr to accnmnlote the '\w\' 
moon, so as to render Oieir inrtumcc Mrti 
tluit actiount the tides in the Mcditen 
Black Sea are loarccly prrcepCiblo. 

These perpetod cooimniinni in the 
occasioned by forces that bcor n very smi 
tion to terrestrial gravitation : the fun's 
raising the ocean i« only Uie l-3t444KOO(> 
tatioo at thr eartliV aurfNce, and the Htiii 
moon IS little more thsn twice as 
forces beinK in the ratio of 1 to ^'1 
sua and moon are at their mean dii 
earth. Prom t}it8 ratio, the 
found to be only the 1-75 part of tl 
Had the action of the »un un the 
octly equal to that of the moon, 
been no neap tidea, and the spring 
been of twice the height wbirh the 
the sun or moon would have prodat 
a phenomenon depending upon the 
the waves or nndulations. 

A stone plunged into a pool of stil] i 
sions a series of waves to advance aiong^ I 
though the water itself i* not carried fo 
only rises into heiKhts and <(inka into h< 
portion of the surface being elevated and 
in its turn. Another 5tone of the a«me six 
into the water near the first, will occoaioii 
set of undulations. Then, if an equal 
wave from eadi atone arrive nt the Mme ap 
some time, to that Che elevation of tb« oi 
coincides with the elevation of the otl 
united effect will produce a wave twice 
either. But if one wave precede the ott 
actly half ao undulation, the elevation ol 
will coincide with the hollow ot the other, 
hollow of the une with the elevation of the 
and the waves will so entirely obliterate one 
that the surface of the water will remain so 
level. Hence, if the length of each ware 
sented by 1. they will destroy one anolla 
tervala of 1-2. 5-2, 5-2, tScc., and vrill 
their effects at the intervals, 1, 2, 3, fce< 
be found, according to this principle, 
water is disturbed by the full of two em 
that there are certain linen on the suKao 
perboHc form, where the water u 
sequence of the waves obliterating ei 
that the elevation of the wntcr in the 
corresponds to both the waves united, 
spring and neap tide«, arising from th<> 
tion of the simple doli-luuur wn. 
is the joint result of the coro' 
coincide in tirue and place ; ami Uir 
pens when they succeed each 
tanral, so as to leave only the ef 
eoce aeosible. It is, therafore. 
solar and lunar tides were of the sami 
would be no difference, consequently 
and the spring tides would be twice as high; 
sepamtrly. In the port of Batsha, io 
where the tides arrive by two channela, 
corresponding to half an interval, tliere 
high nor low water, on account of the 
of the waves. 

The initial stale of the ocean bos no 
the tides ; for, whatever it« primitive 
may have been, they most soon huve vai 
the friction and mobility of the fluid. 



othor! 



MAGAZINE OF SCIEl 



[Able circomsUocet in the theory of the 
urnnre Cbnt, io coiiitrtjucnce of the 
be tra bruti^ only otip^tifth of the mcAn 
Ike earth, And the e&rtb ixjteii Lncrra&ing 
>wartU the centre, Ctie stability of tbe 
of the uoean never can be aubvcrlej by 
t cause. A general inundation, arising 
I initabilit; of the ocran, is, therefore, 
A variety of circumfUnces, however, 
iuce partial rariatiuus in the e()uilibriu[u 
which is restored hj mean* of currents, 
the periodicaJ melting of the ice at the 
ioD temporary watcr-countcfl ; bttt bj 
t important cousea are the centrifu^ 
td by tbe velocity of the earth's rotu- 
riatioiM in the density of the tea. 
riftigal force may be rMoWed into two 
pcrpeodkular, and another a tangent to 
nirface. The tangential force, thoogh 
BtcieoC to make the fluid particles within 
rdea tend towards the ecjiuitor, and the 
much increased by the immense evapo- 
«qtuitorial r^oott, from the heat of the 
ifiitnrbs tbe eqoilibrium of the ocean. 
f ftiso be added the superior density of 
near tbe polei), partly from their low 
, and partly from their gravitation be- 
uni&bed by the action of the sun and 
that of the seas of lower latitudes. In 
of the combination of all these cir- 
^ two great carrcot« perpetually set from 
iwards the etjaator. Uut, as they come 
dea where the rotatory motion of the 
earth is very much less than it is be- 
fOpics on account of their incrtiB, they 
ately acquire tbe velocity with which 
irt of the earth's surface is revolving at 
ial regiom) ; from whence tt follows that, 
ty-Ave or thirty degrees on each side of 

ocean apj^ars to have a general roo- 
Ut to west, which )■. much incrcMcd by 
)f the trade winds. This mighty mass 

waters, at about the tenth degree of 

lie. is tamed towards tbe north-west by 

H America, runs through the Gulf of 

it, pasemg the Straits of Florida at thi' 

miles an hour, fomis the well-known 

■' Neam, wliich sweeps along the 

V 'I, and ninfi norlliward as far 

L _. ..^ .. ;uiiodlQnd, whence, bending to 

wt Qows piut the .\zores and Canaty 

■ It joins the great westerly current of 

uboot latitude 21" north. According to 

pboldt. thix great circoit of 3800 leagues, 

r f The Atlantic are perpetually 

1 ■' purallels of eleven and forty- 
o.iiude, may be accomplished by 

rticle ill two years and ten months. In 
fi this rnrrent is situated the wide Aeld 
■c«-we«d. called the grassy sea. Be- 
there ore branches of tbe Uulf-itream, 
sy the fruits, scrds, and a portion of the 
the tropical climates to oar northcni 

nl westward motion of the South Sea, 
iih lii^ Ennth polar carrent, produces 
V in the Paci6c and Indian 
the one or the other prevails. 
vi Uie Pacific, causes currents lo 
■Ide of Australid, while the polar 
along the Bay of Bengal -. the westerly 
becomes most powerful towards Cey- 




lon and tbe Maldives, whence it stretcltea by the 
extremity of the Indian peninsula, past MadagnM-ar, 
to tbe most nonheni point of the coutincnt of Africa, 
where it mingles with the general motion of the 
seas. Icebergs ore sometimes driAed as far as the 
Azorea from the north pole, and from tlie south 
pole they have come even to the Cape of Good 
Hope. But the ice which encircles the south pole, 
extends to lower latitudes by 10° than ttiat which 
surrounds the north. In consequence of the polv 
current, Sir Edward Parry was obliged to give u^ 
his attempt to reach the north pole in the year 1827, 
because the fields of ice were drifting to the south 
^ter than his party could travel over them to the 
north. 

As diilinct coirents of air traverse tbe atmos- 
phere in horizuutal strata, so, in all probohihty, 
under ctirrcnta in the ocean flow in opposite direc- 
tions from those on the surface, but it is nut easy 
to prove their existence. It is supposed that an 
under current from the Meditemuieaa seU in 
through the Straits of Gibraltar. Tbe surface 
stream flows the contrary way. 



HINTS ON THE MICROSCOPE. 

Tt> the JiiUtor. 

Sift. — If you think the following remarks worthy 
of insertion in your very valuable and interesting 
journal, you will oblige me by inacrttng them. I 
am sure they will prove interesting to many of your 
readers ; there is nothing original in them, but I 
think, perhaps, the generality of your readers may 
not have met with them — they are all relating to the 
microscope. One very interesting subject is, the 
examination of the pollen tubes, or boyeaux of dif- 
ferent plants; I believe Dr. Aldhdge. of Dublin, 
in au elaborate memoir, first showed the meciiud uf 
obtaining them in the same state as that in which 
they perforate the stjgmatic tissue. They are 
readily obtained from auy pollen merely by acting 
upon it by dilute acids, nitric ( 1 to 7 of water) ia 
perhaps, the best ; if a drop or two of this be pUced 
Qponoue of the glass alidea, and the pollen «p rink led 
upon it, or what is better, if the atamens of a 
flower be touched with the slide, then the dilute 
acid dropped upon it, in a few minutes, by the aid 
of a very moderate microscope, the tubes will be 
seen shooting out beautifully. If they do not 
readily conic forth, heating tbe slide very slightly 
will produce the effect. Dr. Aldridge lays they ore 
eliminated upon the »tigma by the acid which he 
aayt is always found there. 1 have not been able 
to detect this acidity of the stigma my»elf, but, per- 
haps, it may prore interesting to yourst^lf or your 
readers to experiment for themselves. Another 
very interesting phenumcnoa is the production of 
tbe Torulo, and mycoderina cercvisiar, as described 
by Dr. Maudl, In his " Traite preetique du Micro- 
scope ;*' these are readily seen by putting a small 
portion of yeast into some weak lyrup, and allow- 
ing it to remain there for two or three days; when 
elongated, filiform, jointed bodies (the above named 
vegetable productions) will be seen springing oat, 
if these are alluwed to remain they will imu-eose to 
a conaidernhle size. Theoe and several other ob- 
jects (such as are spoilt by drying, but are prepared 
by means of water,) arc best preservetl as men- 
tioned by Dr. Maudl, by making some very thick 
syrup, and preparing them with this in tbe same 
manner as we use Canada balsam. Spiral veSficU, 
stomata of plants, and pollen lubes, Sir., are beau- 
tifully preserved thus. — Tlie syrup should be made 



5« 



MAGAZI 



IF SCIENCE. 



in the ordinary wijr, mn Id inedietne, ouly it ihould 
not be ctirred till cold, as by allowing tt to »tiind 
any f.xaen of »ugiT ii jirf^tpitAipd in cryftals, which 
mi^bt tske place in tiie slide of our ubjrct. utilr» 
avoided tbns : — wbco objects are pruerrpd in ihi* 
manner, they should be subjected lo consiilerahle 
prcMure until they are thoroughly dry, and then the 
sbacci exti^tioe WtwLfn Xhc gliua plate abould be 
filled (by capillarity) with white bard spirit v'orniah ; 
ill thti niELnner they are benntifully and permancutly 
preaerved. Spiral vusels are Tcry easily obacrved 
in any pbiEnogaoiona plant, but the conical tenniaa- 
tiona are very djtbrult to procure m the ordinary 
way : we are directed to boil the bulb of a hyacinth, 
then dissect out the ipiraJ vcaitela ; but the easiest 
plan is to take the flower of a hyarinth, put it into 
■ome wtt water, let it remain until the water be- 
cotnea slightly putrid, when the flowers will be 
found almost exactly like a jelly, the rpirol vessels 
ore very easily separated, pick off one of tbe seg- 
ments of the periiinth, press it tirmly between two 
glass tides, when towards the apci of the segment 
the terminationK will be readily and abundantly seen, 
or they may be disaerled trom the macerated seg- 
ment very easily, as they are so few in number ; If, 
after being laid between the glass isUdes, the slides 
are kept pressed firmly in a small pre^i?, and thtn 
the spaces between the glasses Ailed, as mentioned 
■hove, with white hard varnish, tliey may be per- 
manently preserved unaltered. 

A beautiful example of cellular tissue is seen in 
the fronds of Hymenuphylliioj Tunbrigensc ; they 
have panicles of green matter in their interior. It 
requires a very perfect microscope to define the 
green particles, but they are the most beautiful ob- 
jocU 1 ever saw. Thick gnm is sometimes em- 
ployed instead of the syrup, but it is not so good. 

J. w. o. 



MISCELLANEOUS EXPERIMENTS. 

Take a imall phial about half full of cold water, 
grusp it gently in the left hand, and from another 
phial pour a tittle sulphuric acid very gradually into 
Ibe water. A strong tertJtation of heat will imme- 
diately be perceived. This, by the contiaoed addi- 
tion of tlie acid, may be increased lo many degreea 
beyond that of boiling water. 

Dissolve one ounce of qnicksilver, witAout heat, 
in I of an ounce of strong nitroua acid, previnu-ily 
diluted with one ounce and a half of water. Dis- 
solve also the same weight of quicksilver, fty meanM 
tffhtat, in the same quantity of a similar acid, and 
then, to each of these colorless solutions, add o 
colorleits solution of ammonia. In the one case 
the metal will be precipiutcd in a hlack, in the 
other, in a ichite powder, affording an ciamplo of 
the difference of color of metallic oxidea, arising 
from different decrees of oj-itihement . 

Writ* with acetate of cobalt, or with a muriate 
of cobalt, previously purified frgm the iron which it 
generally contains. When the writing is became 
dry, tlieae letters will also be invisible. Warm the 
paper a little, and the writing will be restored to a 
beautiful hlHf. 

Put a Uttle fresh calcined magnesia in a tea-cup 
upon the hearth, and suddenly pour over it as much 
concentrated sulphuric acid as will cover the mag- 
nesia. In an mi>tant sparks will be thrown out 
and the muturewill be eom plrteti/ ignited. 




Pat a little oxymnriate of potAss *i 
phosphorus into on ale filass, |R>ur some 
upon them cautiously, so as not to cjifi.^i|| 
Now take u small ghiss ttihii, and pdoi 
some sulphuric add ; then place the C 
the upper orince, and, in this state, wj 
tube, which muat bo inslanUy imam 
glass, so that, un rcmonng the thoml 
msy be immediately conveyed upon the 
This experiment ik an example of a v 
phenomenon, cttmbuMtion untler water. 
Proceed, in all revpcctji. as in Che 
ment, and add a morsel of phosphuret 
Uere. be&idca the former appearance, we 
eomlfuntton aUn on the surface of the ir. 
MijL one ounce of litharge of lead with 
of pulverized muriate of ammonia, and i 
mixture to a red heat in a dein tobacco 
itMrcase of temperature will separate thj 
in the form of gas, and the muriatic acid 
bine with the lead. When the compo 
melted, pour it into ■ meLilUc cap» 
have a true muriate oj lead of a bright yel 
the brilliancy of which may be much hei, 
grinding it u usuoj with oil. la tliis 
the color called patent yettow. 

Take one ounce of red-lead, and half 
of charcoal, in powder, incorporate 
mortar, and then 611 the bowl of a tol 
with the mixture. Submit it to an intcfl 
a common fire, and, when melted, pouf 
slab. The result will be mettJOc lead 
revived. 

Take a little red-lead, erpose it to 
heat in a crucible, and pour it out when 
result will be metallic glass, and will for 
ample of the ftitrifieatiim ofmetaU. 

Boil equal parts of auoatto and com; 
in water till the whole are dissolved, 
produce the 2»ih rethluh Anff so much ii 
sold under the uame of nanJireert dye. 

If muriate of tin, newly made, be added 
tioQ of indigo iu sulphuric acid, the oxyl 
indigo will be absorbed, and the solatioa 
converted to a preen. It is on the same 
that muriate of tin is employed in 
loured leather fiirniture ; as it absorbs 
and the leather it rtstored /o iff natural 
Write with dilute nitrate of rilver, w 
dry, will be entirely invisible ; hold the ^_ 
a vcasel containing sulphate of ammonia^ 
writing will appear very distinct. The li 
shine with the metallic britliancy rtfttUtr, 
Write with a solution of muriate of cd 
the writing, while dry, will not be perorpi 
if held towards the Are, it wlU then wni 
come visible, and if the muriate of tx>b«lt 
in the usual way, the letters will appear ol 
gsnt green color. 

Take two grains of oxymnriate of poti 
three or four grains of flour sulphur, and 
ingredients very well on paper. If a Utdi 
mixture be Ukeu up on the point of a k 
dropped into a winc-glflsji ronttuning somei 
acid, a beautiful column of Jiame will be p 
the moment the powder comes in contact 
acid. 

Take a small phial, in one hand, coo 
pulvcrixcd muriate of ammonia ; ponr a lii 
upon it, and shake the mixture. In this 
a Kcntation of cold will immediately be fd 



V Ijjd — Publlilied by \V. BsinAix. U, t'aicwi 



GAZINE OF SCIENCE 



^nO ^cttool of ^r». 




S9 



MAGAZINE OF SCfENCE. 



CRANES FOR RAISING WEIGHTS. 



Cbjink* are cctUin nimpltr tnuchtncre in which citbrr 
Ute wLccI onil axir, or wbeol and pmiuD, are intro* 
ducrii, to elTect ihe raUing of heavy loadt, such af 
the loiiditit; or unloading of ihipping at tlic 4uay9 
or whiirfs, or the raisin)^ or loweriotf goods to and 
from chambers or warehouses. 

Various modcfi have- been adopted to turn the 
nheelt ur that pare of the machine which b applied 
to the laiue purpose, hy iutrodudDg ioiif; kt^tvea 
into tbe «x1r, by which it acquirer the name of a 
capstHDt or windlass ; or by a rope possinK over the 
wheel, and potting it and the axle in luotioD by 
fricCioo. Oiber methods have been adopted, soch 
as fonuiag the wheel holluw, aad causing it to re- 
toItb bj means of laborers iuaido of it, walking up 
iU side, which cotiicquently descends beneath their 
wsight ; or by fomiiug it into a platform, lyiuK i» 
» alanting direction, and tbe laborcrH pushing 
ftfainst a fixed arm. which forces the platform or 
wheel round under their feet. 

Moat of the cranes couainicted with the whecH 
an4 aals occupy too oiach space, which is of im- 
portance, and, consequently, where cranes are in 
j^euemi use* have becu superseded by the wheel and 
piuiua, wbtiJi is uf a more compact and convenient 
conttnictioa. The wheel and pinion is generally 
accoDipanied wicba raichei-whecl and pall, or some 
other method of lockini; the handle, ao that, should 
ihe Inborer draiAt from his exertion, the load may 
return to the place from whence it has been 

tht frame-W(rt-k. or that part of Ihe crane which 
dbes nut imiucdtiiifty oprratr to nuso the load, is 
divuleH into three part*, tike post, the jib. and the 
Stay. Tbe post i<t the upright ptc<x, almost nni- 
«eisally made to turn uo a centre; the jib ia the 
•TV cjitendiii^ from the upper part of the post, and 
Ml aoine atsca is horizontal, but more frequently at 
an angin to the horizon ; and tbe stay is that piece 
which sup]Mirt9 the jib, reaching from the lower 
jKirt of the post to nearly the extremity of the jib. 

The must simple furin uf the cruue is tiuttcom- 
mouly used in dtone and timber whaKii for unluad- 
ing TCMela. for which purpose it is well adapted, ita 
power beii)^ Very great. U has a frame consiAting 
of a strt'ng bvam supported horizontAlly at 10 or 12 
feet from the ^rLMind, on the tup uf several vertical 
posts vpry (irtoly lixcd in the ground, and securely 
braced with ftoys in every direction. At the eE- 
trciiiity of the buriccmttil beam the upjwr |*artof tlie 
jib tft supported, the lower pivot resting on a post 
is the gruund. The jib, ur gibbet, as it ts called, 
Iroco a rtisemblance to that machine, i» a triangular 
IhUDe ot wood, one hidi: being pcrjKndicalar, and 
ivppOried uu pivots at the top and bottom, so that 
the whole movt-s round on these ai a vrrtical aii« 
of motion. Near the upper end of tbe perpen> 
dicular post, a beam piuceetU, furmin^ the upper 
nt\e of a triaogle, whila the thirii oidc is a brnce, 
extendrd from the foot of the perpeu dicular, to sap* 
port the upper piece. From the extremity of the 
latter, the burden ifl suspended by a, rope passing 
over a pulley ; the other end of the rope ts coiled 
rouoda vertical roller, or capstan, tumini; on pivots, 
Ooeiuppottcd by the horuonUiI btMm tirat men- 
tioncj, and tbe other uu » post in the grooud, Tbe 
capstan is turned round by means of long hon- 
stootal levers lixcd to it, at which a great number of 
men may be employed to posh tb»ti round, or, in 
Mjuo outcSf UiL-y arc drawu by borsos. Aa the 



Irvrn admit of a very great Icoylli in proporliOft MT 
the diametrx of the windhus on which tht* mpc ooila, 
the pmrer of this simple crane is very c^oMderabla, 
and may be doubled by a pair of hloeks or pulUta 
at the jib. When the harden U raised la n *iitB- 
cient height, by turning the capstan, tbe jib, b^taf 
swang round on its pivots, wilt convey the load into 
a cart or woggon placed on tfaorc by the side of tbe 
crane. 

Another kind of craac. whieh is eqaally comi 
with the above, bnt used for lighter burdens, 
the same jibs, as indeed rooi>t cranes have ; but Ar 
windlass, or barrel for the rope, is placed faorisoa- 
tslly, and has a large vertical wheel fixed apon 0. 
lliis is made of two wheels fixed on an axia at a 
distance apart, and united by boards, so as to form- 
a large hoUow cylinder or drum. Several men fd 
into this wheel, and by constantly walking nnwirU 
on the inside, give it a tendency to rev 
wind up the rope on the barrel. It is su : 
that so imperfect, this should have been so uutci- 
snlly adopted as it was, till within these few yrara. 
Kven when the wheel is sixteen feet in dlameiVf 
the laborers within cannot walk so far up it, tea 
tbe perpendicular, as to have any effective 
to tarn it round ; tbongh tbey a»c always ex\ 
to danger, and frequently meet with the most shodt- 
ing and fatal accidents, from clipping down in tktf^ 
wheel, or from being overpowered by tbe Ifwr) : in 
this case, the wheel runs back with an ac 
velocity, and tbe people are thrown aboi. 
most dreadful manner. Prom tbaae defect oi uif 
common construction, skilful mechaciciaaa hum 
devised cranes that are not only more safe, bat non 
powerful in their operation thnn the common walk- 
ing crane. Some of these wdl be described in Ite 
present artidc, 

A crane is to be cooaidervd as if cottoiating of t«» 
distinct parts : — that which comomnicntea modM 
to the rope or chain, to which the weight ia at- 
tsched, and that which cuabka tke force to act 1« 
any required podtioo or coavetdent dtslance. Il- 
will be eccn, by the consideration of the next 
that we ahaU describe that the Utter part ii 
always necessary, especially when tlie only 
to drag the weight towards it. 

Fig. 1. Represent* the cellar or portaUe 
One side of it only is shown, the other nde k«fl|| 
the same framework, and a similar handle t^$»^ 
winch ; the wheels only being omitted. A B ii 
iron framed side ; B. tJte handle tnma the 
which works in the large wheel IK Around 
axis E, of tbe large wheel, one end of the rapt If' 
coiled : the other end holds the weight to be raised* 
Tbe action Is so simple thut it is not neoessary |ada> 
scnbe it, except to remind the reader thai the 
will be in proportioo to tbe size of the twa 
Thus, if two men apply together Ihf" power 
hundred weight to the winches, and the small wl 
attBchtd to their spindle be of six teeth, while iW 
large wheel has sixty teeth, Ihry would be ablf tt 
raise tea butulred weight — that is. fupponag Ut 
drum or axlei rouud which the rope cotls, be s^b 
to the diameter of the large wheel, but if tlusbe<f 
one quarter the size of the large wheel, m fartSnr 
advantage of four to one is gained, jiti ' '' *- ■ ti* 
would be able to raidc two tun^ i'l 
weight. If a greater power b« req-; 
wheel may have attnched to it a - 
teeth, and if this work a third whe- ' 
ibo rope being attached ' 
the power «uuld be in. 



MAGAZINE OF SCIENCE. 



lA nin tha weiglit vonlil be in the 

p f opoftiun looffcr. 

Manf iKber pnosiracttons o( -nhecl-H-ork are id 

for crjtirs. Wbcii tbcy arn tumrd by a 

wioA it i» [WttpTT ifj Mppty • lly wheel to thr cad of it, 

m i» trikTvannted in h|r. 3, both to e^u&lixt the efforts 

Ike labsrvn who turu tt, rbiI in case be acci- 

itaOf lct« gQ Use bitidlc. to prerent the load from 

down Ki qnickly a.<t tn codanKcr anythioj^. 

Thm rrm««, Ag. 2, is adiptrd not tnrrcly to lift up 

wicbts, but. bjr having n lateral motion 

ft ee&tre, it is capable of depoeitiog them on 

■C a certain distance ou rjtber Hide of it, 

m mmj bv nqoired. A ii « strong jrun pillur which 

tiitf whole of the crnnc abore it. Thia it- 

m m Wliow cfaambcr brlow the grotintl, rnt- 

}f tm a pi«ot belotr, and partly on a broad 

id MctMM ball at D. CC u the jib. formed 

or iron ; B u the faandle and amall wheel, 

«<arka the lar^ wheel that bears the drum for 

{ F M a fly whed attached to the winch ; 

— Ihat u, a strap of iron, which, beio^ 

Co the fly wheel by holding the handle, 

• suffideat fnctioo when the i;oods are 

i H uhI I are guide wheels or puUica for 

to work in. 

BrmBah*s m^mtotu hjrdrostatic principle of 

■ fmU power is applicable in several ways 

lag of heary weights, and has been fre- 

iffUntd in poverfnl cranea. In these the 

iv M« «bcuaed by wheel-work, puUie*. or 

ordinary tnecbftnical powers, but oo the 

of the eiperiment called the hjdrofttatic 

«hWb has been known for ages ; but the 

«i iu powers to mefnl purposes it> due 

Bnaak. 

form if, for a macliioe to raife a 

■ m amall height. A metallic cylin- 

lUf stronf, aad bored trnly cylindrical 

aolid piston httrd into it, wbicb is 

fohvtlj water-tight, by leather parking 

edfe, Ar other means used in hydraulic 

^he bottom of the cylinder most be made 

' drBay with the other parts of the sor- 

" the greatest strain which can OTer be 

to ix. Jn ibe bottom of the cylinder is in- 

ttitt c»i uf the siDJiIl tube, the aperture of 

Bnsas«nicates with the inside of the cylinder, 

tmdncKB water or fluids into it ; the other 

A* pipe eonunuucatcs with a small forcing' 

bf «ldd> the water c«n be injected into the 

its pUton ; the pump has, of 

to prevent the relom of the water. 

the diameter of the cylinder to be 

id the diameter of the piston of the 

or injector, only one-quarter uf an 

prnportioiM between the two surfaces or 

[^■^to* •■id piatun? will be as the squares of 

MUa, which arc as 1 to 24 ; therefore, 

*fll be as 2 to 576; and supposing- the 

space between tliem to be tilled with 

If ether denae and jaootnpressible fluiil, 

lUffl to the until piston will opernte on 

Iba above proportion of 1 to ^70. — 

MuU piston, or injector, to be forced 

In the * • ' ^ or Injecting, with 

■ JO rwt . L*4sily be done by 

'*lf*g ieici. L..., ,.i....,(i uf the ^reat cyliii- 

Chan b« moved np with a force cquol to 

"by Af6. 
Mpmmta a crnns constroctrd upon the 
' poaciplc, tbalia, by lh« iajacUon of 



water from « small pump into a larpi cyUn 
which if ftttf'd with a pifton, linvin;; « rack iittaol 
CO it, for Che |iurposc of lurnin); a piui«>n upnn 
aii» uf a Isrgv drum-wheel or barrel, round 
the rnpe is roiled, and from thence posses tn the 
The figure A A represents the jib, made of i 
and supptirted npon two brackets, projecting from 
the wall of the warehouse in which the crane is 
supposed tu be erected. The rope posses over tbe 
pulley I, and down through holes in the bmckets, 
then turns under the pnlley L. and comrs to the 
lower side of the great drum-wheel B. Thu pinion 
C is fixed on thu same axis with this, and its gud- 
gvons turn in small iron frames, bolted down to the 
floor of the warehouse. Tbe pinion C is acttisted 
by the teeth of the rack D, and a small roller pi 
sea against the back of the rack* to keep it6 
up to the pinion. The rack is aitaclied to the pii 
D of the cylinder, in which the poww for working 
tbe crane is obtained. Tbe piston passes Cbruu|g 
tight collar of leiither, on the top of the cylindo 
£. which does not admit of any leakago by tbe 
of it, ond llicrefore if any water is forceil into 
cylindor, it must protrude the piston from it. Tbe 
cylinder is supported in a wooden frame FP, and 
has a small coj'prr pipe proceeding from the lower 
end uf it, communicating with a small forctng-pa 
at H ; this stands in an iron dattm, which coui 
the water, and sustains the standard, for the ccn 
of the handle G, with which the jiamp is worked 
by one or two men. The upper extremity of the 
standard guides the piston-rod of the pump, to con- 
fine it to a rerlical motion ; nnd there is a weight for 
counterbalancing the handle G of tbe pump. F 
what we have said before, the opi^ratiun ui this 
chine is evident ; the power uf the cylinder iSf 
proportion to its sixe, compared with the siEC of 
pomp ; but, ss it only acta ilui>uf!h short Urn 
the pinion and drum B are necessary to raise tbs 
weight a sufficient height. 



list^P 
king 

i 

The 
and 

.DWOC 

it^l 
cnql 

rked 

the 

con- 

'. for 

i 



STEEL PLATES POR ENGRAVING. 

For several years past sheet steel has been used 
large quantities, instead of coppor-pUtes. by 
engravers. By this fortuuntc application of 
darsblo snd, it may be added, so economic.^ 
material, not only has a new licld been discovri 
admirably suited to yield in perfection Llie ricl 
and finest graphic productions which the Ingeni 
of modern art can accomplish, but to do so through 
an amazingly numerous aeries of impressions, wii 
out percepcible deterioration. Tbe art of engrai ' 
on iron or steel, for purposes of ornament, and 
for printing in certnjn cases, is by no means s 
covery of modern times ; bat the substitution 
the latter material for copper, which has in*itrd 
superiority of tlic British burin to at^hievciu* 
hitherto uoattumpted by our artiatSi is entirct] 
modern pmcUce. 

In the year 1810. Mr. Dyer, an American me^ 
chant, residing in l«oiidon, obiaincd a patent "Afl 
certain improvements in the coustruction and ia^| 
thod of using plates snd presses, &r..'* the prin- 
riplrs of which were communicated to him by li 
foreigner residinc abroad. This foreigner was i^M 
Jarob I'erkitis, an iiiscenious artist of New Eugls^H 
and whusc name subsequenltr iKcame m exB^^ 
sively known in tliis country*, in connection with 
roller-prrsit priiitiui; from hardened steel plates — 
Tbe plates turd by Mr. Perkins were, on tho sver- 
agc, aboui five-eighths of an inch thick ■ they «4te 



» 



cither of »t<el, to tirnpered iw t« Bilmit of Ihr ope- 
ration of the iraTcr, or, as was more generally the 
rase, of itrel decarbonated, so an to become very 
purr soft iron, id which case, after they had re- 
ceived tlie work on the surfaoei tbey were case- 
hardened by cementation. 

The decarbniiiitini,' process wai performed by in- 
closing tlie plate uf cait steel, properly sbiiped, in ■ 
enst-iron box or case, filled about the plate to the 
thickness of nbout an inch, with oxyde of iron, or 
niHty iron filings. In this state the box is lated 
close, snd plsred in a regular fire, where it is kept 
at a red heat during from three to twelve days. — 
Generally about niae days are sufficient to decar- 
bonise R plate (ivr-et^faflu of an inch in thickness. 
When the engraving or etching has been executed, 
the plate is superficially conTerted inln steel, by 
placing ic in a box, as before, and surrounding it 
on all sides with a powder, made of (K|ua1 parts of 
bnmed hones and the cinders of burned animal 
matter, such as old shoes, or leatlier. In this 
state the box with its contents, closely luted, must 
ht exposed to a blood-red heat for three hours ;— 
after which, it is taken out of the fire and plunged 
perpendicularly edgewise into cold water (which has 
been previously boUed to throw off the air) ; by 
this taeans the plate becomes hardened, without tl^ 
danger of warping or cracking. It ts then tempered 
or let down, by brightening the under surface of the 
plate with a bit of stone; after which it is heated, 
by being placed ujion a pieet; of hot iron, or melted 
lead, until the nibbed portion Ao<|uirea a pale straw 
color. Fnr this purpose, however, the jiatenlee 
r.\preS9ed himself in favor of a bath of oil. heated 
to the temperature of 4G0^, or thereabouts, of Fah- 
renheit's scale. The plate being cooled in water, 
and polished on the surface, was ready for use. 

In 1924, the large gold medal of the Society for 
-the Kni^ouragemfMit of Arts and Manufactures, was 
pre»4mted tu Mr. Charles Warreo, for the com- 
munication of a pnper on improvements in the art 
of engraving on steel. The death of Mr. Warren, 
in the interval, bt^twcen the adjudieation of the 
medal and the d.iy of annual distribution of rewards 
having prevencetl the society from receiving such 
details as were expected from the inventor himself, 
the (Committee drew np a report on the subject, from 
wlilrh, along with details communicated by Mr. 
IMiclps, and others of Mr. Warren's personai friends. 
the Account published in the Society's Transactiona 
-was coinpile<l. From this authentic source most 
of the following particulars are derived : — 

Some of the earliest specimens of engraving oa 
'Steel, for the purpose of printing, were produced by 
Albert Dnrer. There are four plates etched by tliis 
artist, impressions of which exist in the British 
Museum, which, in all book« treating on the subject, 
are recorded as having been executed In steel ; of 
these, one has the date 1510 inscribed on it. Since 
that time attempts have been made occasianslly to 
employ steel instead of copper, w a material to en- 
grave upon, but apparently with little success, on 
account, principally, of the great hardness of the 
material, which in a short time blontcd and de- 
stroyed the tools which were made use of. 

^•teel, as is well known, exists commonly in two 
states, the elsstic and the brittle, the former being 
eonuderabty softer than the latter; of the elastic 
steel, a saw-blade may be considered as an example, 
and, in fact, pieces of saw-blade were the material 
upon whieh nearly ail the earlier attempts have been 
made, of late ye>r«, to revive a practice which, if 



sttccrft»fnl, offered so many advaoLtgea to ih^ 
and to the public. Mr. Raimbsch. a ft-w \c,m afOv 
executed au engraving on a block >iy of 

steel, but met with ao many dm i iLe 

execution, that his experituent remained iu4uUl«4, 
and produced no sensible eircrt un the art u( t^- 
graving. 

Mr. Warren, io bis early youth, was intich o^ 
ployed in engraving on metals, for the nee of calus 
printers and gunsmitha ; and the expcrieooe Ihos 
acquired, induced him afterwards to turn bis attcDttoa. 
to the subject, with a view of applying it to the ins 
arta. It was suggested to him by Mr. UiU, oms of 
the chairmea of the committee of mechamci., ihol 
the method employed by the artificers of n^rmiog- 
ham in the manufacture of ornamental aoulliera aii 
other articles of like description, is, to aobjeeft At 
cast steel, after having been rolled iuto sheets, tt 
the process of decarbonisatioo. by means of whiob 
it is converted to a very pure soft iron ; being Klua 
made into the required instrumeot, or other arCish^ 
the omameoted work is engraved or impressed M 
the soft meuUic surface ; after which, by 
tion with the proper materials, it ia case* 
or again converted, soperficisUy, to atoel, and tial 
rendered capable of acquiring the highest polish. 

In the attempt, however, to apply this proremi to 
plates for the engravers' use, two opposite '. 
occurred: a plate of steel, of the samr 
as that of common copper-plate, when 
decarbonised, and thus reduced to the ctate 
flofl iron, yields readily to the graver and ol 
and, especially, ia susceptible of the p 
knocking-up: this consists in scrftiiing ovt 
with the graving tool, and aftarwmrds 
underside of the plate with a punch an 
in order to raise the eaviCy lo the general 
tbns allow the artist to take the error out 
occasioning any onevenneaa of the enpmd 
it was found, however, that plates of Che 
requisite for this operatioo, and of the naoal 
ficial dimensions, were very liable to 
last or re-carbonising process, and were th* 
capable of giving perfect impreasions. If, 
to avoid this disadvantage, blocks, or pUUs, 
or four times the ordinary thickness, warn 
uac of, the warping indeed was prevented 
the same time the process of koocking-np 
impracbcable, and it was necessary, in order 
move any error or defective part, to grind 
Burfaoe, or to drill a hole from tlie under » 
almost through the phite. and then, by forcing in a 
screw, to raise that part of the face which was ia* 
mediately above it. This Utter proeesa, however. «iS 
so tedious and difficult, as exeeedingly to 
from the advantage of substitnting steel for 
In this state of things it became a very in< 
object of inquiry, to ascertain how many imp: 
might be taken from a plate of soft or decarl 
sleel ; and it was found that audi a plate, 
aeoording to Mr. Warreu's process, was oS] 
affonliog several Chonaand oopiea. without u 
going any sensible wear. In proof of this, the ooa- 
mittse of the Society of Arts, tec. state, that is- 
preasions were laid before them by Mr. 
from two plntrs of decarbonised steel 
him, thr one for an edition of Mackenzie's 
published by Cadell. the other for an 
Beattie and Collins, published by Rtvington 
pistes exhibited, both in the landscape Ukd 
figures, the most elaborate and delicate work 
thousand impreaeions had been Uken fnoa oaa% 



rart«M 



cap^J 



Warns. 



MAGAZINE OF SCIENCE. 



61 



td {rem the. oUier ; und jet between one 

id unr of (he Intit Imprruiouft it wu 

lie to perceive »ny difterencc. 

r- WErren hid rarried nn bii experimentx 

rorking by btmself till lie bad bronght bis 

Lpfcrfccrlion, it la probable Uiat, at the period 

"t, the evidence of the great importance 

rery wouM by no mr«ns have been so 

it bctn&lly «ru : nnd the renull of hia 

It hsTc been lost, to the i^reat drtri- 

>fp«flion, and of the fur fame of thii 

'wtift. Bnt selfishnrftt and aecrecy in any 

ieh related to the impro^einenc of the art 

he wa.4 attached formed no part of his 

; and all his discoTeries, both those re- 

the pnsparation of his pUt«a. as well as 

LCh had reference to the eneraving upon 

aDTMcmdly and gratnitously commnni- 

Gooseqoence of Uiis liberality wan, that 

plates of Mr. Warren's own engraTing 

hefore the committee above mentioned, 

of portraits and other suUjecta cngraTed 

steel were shown, demonstrating 

►,000, and eren 25,000 impreftnoDs 

off steel plates, before their respective 

them for the prodvotion of their 

^uren's original process for decarfaoniain^ 
'^htet consisted in procuring a box or case 
id corcrini? the bottom of it with a mixture 
lings and ponnded oyster-shells ; on tlits 
t* is Uid ; another bed of the mirtarc is 
and so on alternately, till the box is 
cire that a bed of the compoflition ihould 
^«pper a« well as the lower layer. The box 
' was then placed in a furnace, and kept 
hours St the highest beat which it wonld 
It melting; after which, being allowed 
Inally, the pUtes were foond to be re- 
the mo9t part, to the state of soft de- 
ft copprr-plate maker,* having been 
'Mr. Warren in his process, and find- 
steel did not always tnrn oat bufliciently 
soft, (particulariy for the purpose of 
in menotinto.) imagined that those oc- 
were owing to a deficiency of heat 
process; accordingly, he snbsti* 
oven of refractory clay, for the cast- 
'leti applying a considerably higher 
the cast-iron box would have endured 
iritkig. WHS ennbled to obtain plates so 

night be bent over the knee. 
»hf|: the cfest superiority of steel-plate over 
^rnrkf that require a considerable 
n<i to be taken, there can exist 
iD^Mi^h the use of the graver, and of 
frt)uirrs more time on steel than on 
[h the process of re-biting has not 
to the degree of perfectiun in the 
been in the latter, yet the texture 
'•neh, as to odtnit of more delicate work 
; and (he hnrst and most elaborate 
of the flrt, which on copper would soon 
to Frduce them to an indistinct smeary 
to uudrrgo «rarrely any deterioration 
mtn the marks of the burnishes arc still 
bhle «ft«r sereml thouband imprcMiona. 

IB Shr« Ltfttf . [fOmloti. wh«rB erery nrticU re- 
■ip«<Kf may be porrbkiod, nd of woellenl 



ENCAUSTIC PAINTING. 

The art of paiutiiig in encaustic Is a manner of 
painting which is executed with the operation of fire. 
Ancient authors of\en make mention of this speiHcs 
of pninting, and which, if it had been dt^scribed 
(.imply by the word eneaustic, which signifies exe- 
cuted by 6re, might be supposed to hkre been a 
specie« of enamej painting. Uut the expreauons 
eneawUo, ptngerc^ jtioiura, -enctaittiea, eerit pin' 
fftTP, fitcfutom, inurere, by Pliny, and other ancient 
writers, makes it clear another species of painting 
is thereby ukauC. We have no ancient pidarea of 
this drHcnption, and, therefore, the prccisw manner 
adopted by the ancients is not completely developed, 
though many moderne have closely investigated the 
8abjectf and described their processes. At whac 
time, and by whom this species of painting was first 
invented, is not determined by antiquaries, although 
it appears to have been practised in the fourth and 
fifth centuries. Count Caylus, and M. fiachclier, a 
pointer, were the first of modern times who made 
experimeuls In this branch of art, about the year 
1749. Some years after this, CouDt Caylui pre* 
sented to the Academy of Painting, at Paria, his 
ideas and experiments on the subject of the ancient 
manner of painting in encauatic. In 1754, the 
count had • head of Minerva painted by Mous. 
Vien, after the proceiis described by himself, and 
presented it to the Academy of Sciences in 1755, 
This success induced Mons. Bachclier to recom- 
mence his experiments, in which he succeeded bet- 
ter than formerly ; but bis manner of painting in 
encaustic differed from the ancients, as described 
by Pltny, and, therefore, be was uosucuwful, iuas- 
much u he did not discover the rtai ancient man- 
ner ; after thia he made some other expcrimenta on 
the same subject, differing from the process as de- 
scribed by Cajlos and others. 

Plmy, in a passage relating to encaustic pointiDg, 
distinguishes tlircc species :— First— that in which 
they used a style, and pointed on ivory or polished 
wood (cfxlro in tbott) ; for which ])urp(ise they 
drew the outlines on o piece of the aforesaid wood 
or ivory, previously soaked or imbued with soma 
certain color ; the point of the style or stigma 
served for this <^eration, and the broad end to 
scrape off the small filaments that arose from the 
outlines, and they continued forming outlines irith 
the point till ibey were finished. Second— The 
next number appears to have been, wliere the wax 
previouftty impregnated with color was spread over 
the surface of the picture with the style, and the 
colors thus prepared were formed into sutoll cyliu- 
ders for use. By the side of the paiitter wa» % 
braxier for keeping the styles continually hot, with 
the points of which they Inid on the colors when 
the outUni* were finished, and spread tlicm smooth 
with the hroflii end, and thus Lhey proceeded till 
the picture was finished. Third — The manner was 
by painting with a pencil iu wax liquified by fire ; 
by this method the colors contained a considerable 
hardness, and could not be damaged either by the 
heat of the ouu or the deleterious effects of tlie aoa 
water, it was thus that they painted their ships 
with emblems and other pictures, and. therefore, it 
obtained the name of thip pttiniing. The Ust pro- 
cess was to smooth and polish the picture i^-thns 
far the aucieuts. 

Few, of late years, have made mora experimenta 
in thia mode of pointiog than the ingenions Mrs, 
Hooker, of Rottingdeon, in ;tbe county of Susses^ 



^.z^:.^ :j science. 



'■- -■* = ■'-* =j^-^-.'. ::^.i-s :—_■::»-- ■»-=t Isz^ *!--«• ^er toem ; but it in less troub 

-"■^~ ~ ■ -"' "-~ -r — .-„ ■- — : — * n *.-oaff T-ii^f- wh*n the colors ire obsrrve 

- * - ■ -- ' '- .•". •-• -' T-T-sa «-- .1 1 — it-j:^ irr. In ptinting with this con 
'" ' T--^-- -^ -^ - _-— j^ :_ I.M.Jx.»e'T--r -a* -currs ':>ad vithoat di£GcuUy when 

--' " _-:_-::_ .z^^ k. — ar « irzran *-■« wi-a cry the tints may easily b< 

- - ■ - ~ -^- » "== *'*Tr'^ i 7-Hsar-:ini^ -hr :- -oioza zi & bniih and a very smitU qu 
"■" "■- " - '--- * ** Irxx m^^f^ J r*^%jn::. vcrr. ^'■••z. the painting is finished, p 
'^ -" ■ ■=-=-:— ^jz -: ^-3 =r--T:T:(^.j- t -i^.^ ti.":* -ru 11:3 a clued earthen vessel ove 

- '-- '"-" '-=-: TV riii- a, =i- --iT '.**-!. riw ir^- ia»i »btfc, Kclted, but not boilini^, wit 
T -;. . » ----! -i .' -- »Ti^ * -n*TiB9 IT "3^ ivLti x'w lie pamtin|[ with the wax, a: 
^~- -- j: - » X— .1 :.- : — -^-jc - -z:: irzx. — v;ii u** k =odera:cly hot iron, such as is 
. ..s . ■,-rsL,^ TS—r -- ■: ::- « .-fjr- » h:?!!-"?:- -ir -j _r^a. i=.'i *o cold as not to bias if 
i:t - . :_T '—as - CT- -*-.iz ~.-it a zae n«am- t-^ i=.i'i -z we:, azd draw it lightly over i 
-rr^-.- ^- - -r_;r^ — - a-. iz'^leFXiT' u;>: T"!- i ."r.-.z *— VP'^s'' ■• if **"***■*" ■*"1'^"' 
s-T. i™r*:"r*. = ac "^tt .-"T e^i^ i -Vroiir vls *s<i vK:^T«r Mi'^tance the picture is 
--»iia;zi.-ic-'H X =r '*«n«!'" T -2e -— RiT rf If: aj«:.T. its zerxjt.t cold ; but if when so, tt 
tarn i^ir tit— «n?rr-2rrnT3 i^— rr- nifog sor; J14 ucLd z:z a^-ptar sufficiently clear, it 
"Z^iS. ':r r :: Hf c^ "a _- — ' '•'-«. Smc^'ixs icui 3«::r; xzt trt kt such a distance as 
UBi^-i : :-- :'^Lr:.=4. izx^ei^; »■ laa -nux'^ :3d vai iw: vly : lt :be wax may be melted I 
■^TTRi --crar^ -»=^ *i.ar-»rs..» Tw ^iiitiwin: jur a i:« pc^Tr a: such a distance as t( 
^ -i^ a ag V3-.--?* "ac "-*^"» rr -n.* ji-j"* ■ r*~j rs'i.-y, «Kca_.r over such parts of the pi 
vrwBVU^BMb o ~ar •^-v:s-~- W2u.--. "s i<.i!*:r T Wtuaui ace apwu- soificiently transparent 
ler 3:rw.Ti±r«* r— -3. ci ir-^aiss a -o:^ rzr-.- -ijaz - ::c ix Mi^iT heat ii applied to the 
•t* " ^i T 1 :^ TTw r*. r-tTLit :e ^ — j ne "ue rrsvr w-J,l b« tos traofparvncy and b 
i^«*»r«-ui =jur 1 !!»-sueC-* ratT:-.:; -C >a:L:---:i^; S-: tie contrary effect would 

"\tf2i •». n wg fc. - zg -.3C r^r — r-^ i .-•inr»rn T-.-e xasfi J tx> f^cicn or 100 great a degree o! 

TT -^i-^^ n TEiTa-a-tt re i« Otris^is .--*=at K:o<fi. :r f:-r ::-o lon^ a time, as it will c 

yi T— ^j - « w^ K 'a^t :▼ 'v.'v S-v^r- wax »o =:3C^ to tLe surface, and may 

7.. — . . ••-v^ -vi:-^ -i^!««s. HUT .-«=:*.-» mi .Tk:^ :x rdiai. Sh^sld the coat of wax ] 

i jn; - — j=' X-,- . mri -irt nc5«* .^ M^ i =K :a:ri.^ waca r.L.jhfd appear in any i 

^~. • ■*. T-:^«r- •: - -srr^ •-B.'y wst-: *::« *«*z. U ray a* rtzEeti^ed by drawing a mu< 

-^j y . ■*^.^-.— 1., *:r n *-^r -Hmr-f .1 rt.-n «.=^ tx l"::i -Tjf ;i a^am. is before mentioned, 

r *. < -: .-'» ^s— E ««i*v*£. jyv:. r.Ltr'i u: r» fcr-ij.-j tts wn wi:h a knife; and shi 

>hric "^-r ?«• re fwsK^ -ruv. .-vaaaxiTrs zxe ■'ai- '} ::o cr--^: ^t too loni^ an application 

jvcarnhj'' «-"-ts^ i:i.~3; :i." :-:r".rs *t particuLv places, byo 

<««N«. n rmsr v a ~^ c^f i^s^ied. cr even a tobacco-pipe m; 

s lai^isfrrv^ >.-i£<^^ :^.f :i::l^ v-_1 subside; or such defects 

-?*.. ?w."iJ VL-.-ic^f -r=: ri :j iriwai* anything hard over t 

. ,.; .1 ,ni»st *• HXTi i» iZA > w:_^:.t».' ri .'4(; any sm^II cavities. When 1 

^ w«. I- -. . ■. •- •««»■ aaw v»4:oi »» ."f:? --ir: » ,"i*i. r>5 sc «:th a fine linen cloth. 

^^ t^ . :^^. V.iw -V iXTs ■-• 3* tr- Mil t*^ 3C» =i? :< ei«:i>d in this manner upo 

,^^-» - - r .t.: >--^--i ---^ml ^wws^ «rr- w-ii :>: f;«w of wood let in behind 

—^ ^ww •- - T. rwi -'. ---t.. -".;-"i!tn& ^.vi*^^r■ lie ^n::2 c* ■^■e wood. ii> prevent it* warpinj 

. ^ ,... ^ ^, -».-.» «.>*. ^^ lae. vutM thn «wk --ari. -v plasser of Pari*. The phuter 1 

-I o, v-^-^^iiv^ -i :h fj~ » ?wu:iT? £ -siii^-r» >.' ,-:i*r prtpar»tion than mixing sc 

.-v' *...-««^» %v^^ iM^'i inr «v. jmi s*uscfc « Tatj in powder with cold wat 

._, . ; , .. ..^ ^ ,^.; Mf::«^v.> *:>^ ^issT. : 3;^ri3e« -f' a cr;ix : then pat it on a I 

../ .it-iC-.w 3. :fc.-i-r >^f U' irr. saU -: | *•■*»- iiT-^a; ar« miue a frame of bees wax 

. -X .=il ■ 'Jvt -.'sae^, t ^x.*!.^ >f 3»wstt iiri , a.vit:a*-*^J«#- the form and thickness of wli 

«n. • ». !* s.-t »«*»*.'« hftiiin; xt*.i »*ca '.- -y 

AV"*" * '"'• '• ■<>"-*«™ ALttfwiniirf ,f' .v.*i »rr-^ 

*^f ;h.'! -i-«ii -:*tf .TrtttjcKtA-e. « *:«* ^r: 

« . i-vt •^.■. .■» -K' t»in w^cv-J. ia*i t« X :s^J 

v "4- • •• 1 w » J'^ ■^.* -"rtOTK wi« a-ifti w::h ::. 
i^ vim^-v* ..- •■■ ^ A. rsf -swcioi .'t wi=£ :: :* 
^ u \ • • -h.- A-«^%iK=-- arv'3 *-. ei.-t=en 







•«: 



f.. V « v.v * .* :v .^' .-.-^ »* :»* nro^ier ;*ew of 
:j»,.' **,.*: .v-'--> - ■-- .-; >^^. -vV-^ : ti« I«in* ^* i 

rv *v»KV^ wSw^ ^- ^'-^ •■■-■ t^' c-.-aTposmoTi. 
,^, S- -w*i '■'■« *^*-**«' »^'*'^ »" '■"•■•• " ***• •"'"* 
«v«r »«Sv\-^v -'« •> '^^J* *c\vu3: :"• * »-v's-:v5^ti.>n i> 
L— , »i*jui; L<T\*-:> » V'v «:iv i\vr:vj;.<r rrans" irir.'y 

ILf, 5w#.'. :: '•'■f ^v:.-r» «t Wd on thiA. a* iVey 
*"!11. ;N' M'-.- KK- of the ^^^*h as if painting 
TTw-M* .v:or». and th* *sv.e bm*h,>5 *# used in 
TL ^"^ cvU'c*. if swwn dry when mixed 

•J" Am. »** be uKd by potting a 



wuitJae plaster of Paha to be. and when d 
ic iS. and there wiU be a very amooth sni 
paint upon. Wood and canvass are best 1 
w.th fome gay tint mixed with the same cc 
taoo of gum arabic. gum maslicb, and wax, 
the same sort of colort as before mentioned, 
tbe dengn is be^gnn, in order to cover the | 
tr.e wood or the threads of the canvass. V 
alM may be done in the same manner wit 
gum water and gum mastich, prepared th 
way as the ma»tich and wax ; but instead of 
seven onnces of maatich. and. when boiling, 
live onnces of wax, mix twelve ounces of gui 
rich with the gum water, prepared as mentii 
the first part 01 this receipt ; before it is put 
nre, and when suffiL-tently boiled and beaten, 
a little cold, stir in. by degrees, twelve oun 
three quarters of a pint (wine measure) < 
spring water, and afierwards strain it. It w< 
equally practicable to paint with wax alone, di 
in cum water in the following manner, 
twelve ounces, or three quarters of a pint (Air 
sure) of cold spring water, and four ounce 



MAGAZINE OF SCIENCE. 



63 



arable. paC them loto a f^Uxed cartbeo 
wben ttie |>um ia tliiiAolved. add ei^hc 
white WM. Pat the earthen veaael, with 
raCcr lad wni, upon n *\ow tirr. and ttir 
^Um wax is ritisolvcd and has boiled a tew 
tben Ukc thecu uff tUe tire, and tlirow 
■ baiin, ba, by remaining in the hot 
Hwlt the wu would beoomo rather hard ; 
Kum water and wax till <iuitc cold. Ah 
ia but a imaU proportion of water in compa- 
Co the quantity of (nm and wax, it would be 
Mf7« in mixing tbia cooipoaition with the 
I, lo put also lome fair water. Sboald the 
Mition be so made aa to occasion the ingre- 

I to acparate in the bottle, it will become 
riceaUe if ahaken before lued to mix the 

very Mmceable quality in the vehiale 
nw diacovered by Mrs. Hooker, which 
composition wluch had reinained in a 
the year ]792« in which time it had 
n4 booome aa aolid a aabitance as wax, 
a cream.like ooaatatence, and became 
u proper a st^te to mix with colora aa 
was first made, by putting a little cold 
upon ttt >nd duifenng it to rrmnin on a short 
" 1 aUo tatelj found,*' says this iogcnious 
** aome of the mixture coropused of only guns 
jiraCex, and gum moatich, of nhioh 1 bent a 
to the iiHiciety of Arts, in 1 792 : it waa 
r. and had much the appearance and con- 
bom. 1 found, on letting aome cold 
lOrer it, that it became as fit for paint- 
M when the composition was first prc- 

fTobt rmtinu*^ j 

FBESERVATION OF MEAT FOR 
FOOD. 

BT M. UANNAL. 

ting is a traofilatioD of an abstract of a 
id before the Royal Academy of Sciences, 
\, Iky M. Gaunol, inveittor uf the well-known 
iwafrnibnUning, 09 given in this Compte ReJtdu 
ttnAk 22, The author commenced by recapitu- 
( msae of tlte incoovenicncea presented hy the 
eonnDonly employed processes for preserving 
I fa« rrinarkctl that, whaterer substance he 
0y«d. great advantagea result from its being 
AMud by ibjection, iuatead of making it iiluwty 
tme, aa in the ordinary process of salting, by 
billon from within or without. 
Bf i^jci.'tion will be obtained, besides the aav- 
If tine and money, an uniform distribuFJon of 
yiwui litjye substance, while by maceration, 
iMIy if largv pieces be acted on, the portions 
Mift the outside, brcomc suprr-saturatrd with 
biAatjaooe. before the internal parta have re- 

II MrfBcient to prerent their decomposition.'* 
•M. defoting himself to the examination of the 
bMeefl wluch migbtbe used instead of common 
I M- tiann>l rtftrred to the soluble salts of 
k nkaUnort which have the power of prevcnt- 
jhe putrid feruieotation of animal matter, but 
f •T •Ki'-' ^ • T~ ■•:iriite to it an unpleasant 

•r IdJi) ties. According to him, 

- iicea exist in the chloride of 

said be, *' theorcLicttlly convinced that 

by this salt in a state of parity, 

DO tasXc^ because, in the first plact*, 




the qonntity used ta vrty smal), asd hejiideft, from 
the reaction which is operated, tberv resulla only s 
small quantity of clUoride of potaiaium, aodmm, or 
calctuu — salts which are dally employed in oor 
hoQfieholds. in the grey »alt consumed in our kit- 
chens. As for the portion of alumina iDtroduoed 
into and corabined with tlie animal matter, it is met 
with in such email qoantities that it need not ht 
stopped. 

" Alum is employed in medioioe, and acts as on 
ostringeut ; but. in this case, the argiUaceuus earth 
u combined with an arid, while in meat it is no- 
thing more than an earthy powder, without ictioa 
on the animal economy. On this subject, it may 
be affirmed that the inhabitants of the borders of 
the Seine, who drink the water of that nver at least 
half the year, daily drink ten timea more otuminoua 
earth than they would take by habitually eating 
meat prepared by my proctMS. 

" Rxperimeuts on the degree of concentration \ty 
be given to my liquid to eifect the preservation of 
meat, wtthoat uselessly adding too Urge a quantity 
of salt, have shown me that the suitable solabon 
ahould mark lO^'of Bsnroe'a Areometer. Now one 
kilogramme of this salt, aa prepared by M. Uuerin, 
is sufficient for six quarts of water : from nine to 
twelve quarts of tJiia liquid are required for the pre- 
servation of an ox, that is to eay, from one kilo- 
gramme and a half to two kilograniinei are em- 
ployed. 

*' The madua operamdi is very simple. Wben* 
the animal is felled by a blow on the forehead, the 
carotid and the jugular are opened on one side, by 
making an inciston ftoox the larynx to those two 
vessels ; then, by a brisk movement, the cattinf 
InstrumcDt is raised, which divides all the parts, 
and allows the whole of the blood to nw oat. 

*' Hlien the blood ceases to flow, a syphon in In- 
troduced into the carotid, a hgatnre is made at the 
superior part to prevent the liquid from moning 
out, both the apertnrefl of the jugular arc tied, and 
the injection is then introduced. 

" The most suitable instrument for this operation 
is a tube of waterproof Unen, of two metres iu 
length, three centimetres in diameter at the bottom, 
and five or aix centimetres at the top i tbis tube 
must be fixed to the syphon, which should be of 
wood or bom. 

*' As suoa as it is perceived that the animal i» 
well injected, that is to say, whea no more hquid 
gors in, and when the subcutaneous veins are vrell 
swelled, tbe tube must be squeesed between the 
finger and thumb, which must be mode to descend 
with pressure for the length of the column ; by this 
means the quantity of tbe liquid is increased in the 
interior of the animal. A ligature u made below 
the ayphun, which ia then withdrawn ; twenty mi- 
nutes afterwards the animal is skinned, then emptied* 
and, finally, cut up ia the ordinary way; there is 
no necessity for removing the boues and fat, as la 
the )iroccss of salting. 

" When the animal has been well bled, and the 
injection welt performed, it ia scarcely perceptible 
that the animal has ludergone any preparation at 
all. The only part where tbe injection leaves traces 
is in the lung», which arc dried up and discolored. 

" When the animal ia cut np and hung in the 
air. the tiesh is left in this state until tt is cold ; the 
only precaution to be taken is to prevent the flies 
from getting at it. 

" Meat which tt ia wished to pre&erve for a cer« 
tain time, requim uo other precaution ; it is suffi- 



G4 



MAGAZINE OF SCIENCE. 



dent to hang it in a dry tnd airy place. ^Vb«n it 
i* intcudcil tu preacnre it mure thim 6fteen iIstd, 
ibo flesh mtut be washed in a tolubon at ten dt^' 
gTtes of ctUoride of aodium, and an eqiuU quantity 
of chloride of alumiouui. W'beu this ia done, the 
meal ia a|iplied to the parpoura for which it ia in- 
tended. That which ia tu be dried, miut be hung 
in a chamber heated by meana of a currcDt of hot 
air, or air charged with wood smoke, or even in the 
open air ; but io thia caae, iliea muat be j^tarded 
againat. 

" Whan this meat is dried, it ii sufficient to pack 
it la barrels hermcticaUy sealed, and to keep the 
latter in a dry place. 

" To use tlus meat, all that is required is to 
macerate it for four-and -twenty iiours, and aa it ia 
not salted, the swelUog may easily be effected in sea 
water. 

" When it ia wished to preserve fresh meat, it is 
piled up in barrclB, aa is done in the common me- 
thod of salting ; when the cask is fuU it is closed 
up i then it is filled with either a saturated solution 
of chloride of iodiuni, with the wsshing mixture, 
or simply with dry chloride of sodium. The three 
means have given good results. 

" Thif bath contribates but little to the preierra- 
tion, but it prevents the vegetatiuo of byttua ; with- 
out this precoufcioD, the meat would become musty. 

" Among the e^iperimonts which 1 made, a barrel 
was opened after three montlu, and a leg of mutton 
was taken out which was roosted and eaten, and j 
pronounced very good by twrlve pursuuH ; but the 
twrrela having been badly closed the Utiuid of the 
bath was losf. and the mt'-at was covered with mould, 
but was not dccompoied.*' ' 

A committee, consisting of MM. Thenard, Ma> 
gendic, Dumas, and Seguier, has been appointed 
by the Academy to investigate the merits of this 
process, and to report thereon. 

MEMORANDA. 

Vt§etttti(m in Atmo»phere§ (^ differmt Dnuitien. 
— The following experiments have been made by 
Professor Dobercmer, of Jena : — Two glass vesaela 
were procured, each of the capacity of 320 cubic 
inches, two portions of barley were sown in portions 
of the same earth, and moistened in the same degree, 
and then placed one in each veasel. The air was 
now exhausted in one, till reduced to the pressure 
of fourteen inches of mercury, and condensed in the 
other, until the pressure equalled fifty-six inches. 
Germination took place in both, nearly at the same 
time, and the leafleta appeared of the aame green 
tint ; but at the end of fifteen days the following 
differences existed : — The shoots in the rarefied air 
were six inchea in length, and from nine to ten 
inchtes in the condensed air. The first were ex- 
panded and soft ; the last rolled round the stem and 
solid. The first were wet on their surface, and es- 
pecially towards the extremities ; the hut were 
neariy dry, 

Sound. — The French academicians made, in 1738, 
some experiments for measuring the velocity of 
aonnd : liie board of longitnde renewed them in the 
Bonth of June laflt, vrith all poetaible precision, 
when they found tlut the velocity of sound in the 
air, at the tem]>eratare of bh° Fahrenheit, differs 
very little from 1014 feet per second. 

The Chtck in Ooo, — Mr. David Ritchie says, he 
hai heard of a mode of discoveriitj; the sex of the 



chick in the egg, UlfToring from any whichj 
proposed by noturalifts. The foUicolua 
air-cell, which is to furnish oxygen to the 
chick, is situated at the larger end of the q|g. 
has not in bU eggs the sanu: poaittftn at the i^gm 
end ; and in varioui districts of Scotland, it ii hi* 
liev«l that eggs bearing the air-cell only 
top of the larger end prinlucc fcmalea. 1 
tain this Mr. R. instituted a series of ex| 
These experiments go \ery far to prove 
opiiuon which has been ilated is correct, 
determine what naturalists of Germaoy, France, 
£ngLand, have endeavoured in vain to disrova. 

Change* of the KaieidoKCfjpe.—Suppoti 
inRtrument lo contain twenty small pieces i 
ficc., and that you make ten changes ia 
minute, it will take the inconceivable space 
462,880,899.576 years and 360 day* to go 
the immense variety of changes it ia capable 
ducioti, aasounting (according to o«r firail 
the nature of things) to an eternity. Or, if 
take only twelve small pieces, and make ten cbai 
in each minute, it will then require 33,i{64 daj 
91 yeara and 49 days lo exhaust its variationa. 

Wei$hl ft/ thf National Debt of E 
BanJt NotM,~Ont hundred men 
the national debt of England in t' : Ik's, 

b\2 of which weigh a pound ; i*o ti :>ga 

of pounds sterling (which was iht i tti^ 

national debt in 1770, when ihi- 
made) would weigh 17»650 pouniI.> : <r A' 

hundred men. would be 437 pounds c-bcb. 

Cnrion* Erperimettt teith a Tulip. — ^tliebalbi 
a tulip, in every respect, resembles abnd. « 
its being produced under ground, and 
leaves and flower in miniatnre, which are to 
panded in the ensning spring, lly cautlaoalj 
ting in Uie early spring, through the ovnMPtilr 
coats of a tulip root, lougtiludinally fron tbft^ 
to the bose. and taking tliem off surxesatvcly, Ike 
whole flower of the next summer's tulip ia beautl. 
fully seen by the naked eye, with its petals, pi 
and stamina. 

The TroveUing of Liyht. — Light travels at 
rate of an hundred and fifty thousand milea 
single second ; and it ifi tfeven mJnutcs in pi 
from the sun to the earth, which is nearly a 
of seventy mUtions of miles ! Snch is the 
with which these rays dart themselves forward,'^ 
a journey tbey perform thus in less than eight' 
nutcs, a ball from the mouth of a cannon would 
complete in several weeks '. But the miuut 
the piLTticles of light arc stiU several degrees 
their velocity ; and they are, therefore, 
because so very small. A ray of light is 
more than a constant stream of minute parts, 
flowing from the luminary, so inconceivably " 
that a candle, in a single second of titue, hail 
said to diffuse several hundreds of milUona 
particles of light, than there could be gnimiBj 
whole earth, if it were entirely one heap of si 
The Btm fbrnishes them, aiA ilie stars also, 
out appearing in the least to consume, by 
us the aopply ; lis tight is diffoaed it) a wide 
and leems inexhaustible. 

To produce Fire from Vane. — The Chioeatt 
ton, which is used, when ipUt, for the maki* 
cane chairs, will, when dry, if struck against 
I other, give fire : and arc used accordiugly tji i 
placefi, in lien of flint and iteeL 



ucaiu ui K uiuoe oi uucuveru)j{ uie bu ui mc | piHccn, in ucu ui uuii. uhi iicct. 




THE 



AGAZINE OF SCIENCE, 

^n^ ^c&ool of ^xt9^ 




SATITHDAY. MAY S3, l&ll. 



riK 




BRIDGEMANS OXYGEN LAMP. 



6C 



MAGAZINE OF SCIENCE. 



s 



BRIDGEMAN'S OXYGEN LAMP. 

7*0 xAff ISiiiiir. 
SxB.— Being engai;ed in the curly part of tbc winter 
of 1839. with B flcicDtific genilcmBa oi this town, 
Mr. Edward Mugridge, iu experimenting with a 
mftgic lanthora, andend^rouKng to obtaia ii better 
light than was given by the common Inoips, utnally 
sold with them ; the idea was soKgestcd by the 
latter gentleman, of supplying the flame with oxy- 
gon gu : the attempt was mode, but dkl not answer 
in the way we tried it. 1 then turned my attention 
to it more minutely, and, after a long course of ex- 
periments, Mucceeded beyond my most sanguine ex- 
MctationB ; my idea was, that it might be obtained 
by filling the interior of the flam« of a common can- 
dle, ur small Limp, with oxygen gas, which has 
proved correct. The gas b passed through a inrt/e 
mperturtr with but littlw pretsurty and produces a 
lights both steady and perfectly under controul. 1 
have had one burning for three or four hours at a 
time (witli a light scarcely to be borne by the naked 
eye, without requiring to be evea touched), and am 
convinced, by my own experience, and the opinion 
of a first-rate London optician, who*c judgment 
may be relied on (und who, when he reads this, will 
see the original of a piracy), that the inrentiou will 
be of great benefit to the optical world, and particu. 
Urly OS its construction is so simple that any one, 
pOMBssing a mudenite share of uiecbanlcal talent, 
may eonstruct one for himself, and on that account 
I have been more partioular in giving Che miuutis 
of what I have found to answer best and most sim- 
ple ill coastrvction. and have given the drawing the 
exact sis*. 

A is of tin, with the brass tube B soldered to the 
hoitom, and projecting about ^ of an inch below it. 
C is a circular broia Ud, with the tubes D and E 
Nolderpd in it, and resting on a wire soldered ronnd 
the inside of A. F is a brai<s ferrule' with one of 
the (hr<^ pins actini; on the screw cut on the out* 
aide of U. G is n brass nut tapjied to fit the screw 
uu the tube H, and locking into the niche on the 
lower end of the tuhe U. }1 iu the brass tube 
through which the gas is passed to the flame, I is 
K tin cup Moldtrtd uu the tube H to catch the over- 
Jlawini; oil. K ts a nut to fasten thr. tube into Uie 
end of thu tube V, the lowereiid of which is soldered 
t« the smnll screw of a comaion uniun joint M, 
which allows it to he attached by a flexible tube 
cither to a gasutncter or gna bag. 

The wirk is made of the common (Vat cotton, the 
two aides l>cing sewn together and placed loosely on 
the tube 13 ; it is then cut ofl* le^'cl with it, and 
opened from the tube n little. Tlie inner tube H is 
about 1-lGthof an inch smaller than B, which hoId< 
it in the centre by three points, filed on its end and 
bent towards the centre ; Oius allowing the over- 
flowing oil to pass down between the tubes into the 
tin cup I ; the gas is thrown obliquely into the 
flame, by the small inverted plstina cone N, which 
is attached to a fine wire, bent so that it may be 
pushed gently into the tube, and remain where it is 
placed. The tube L tsrves to support the lamp by 
boiiig fixed in a spriog socket, and the Inmp rest- 
ing on the nut G, tlie end of the g&s tuhe may b« 
ndjuftvd to a great nicety in the flnme, by merely 
turning the Lamp round — a practiral point to be at- 
tended to. Another great advantage of this form 
of lamp is. that it may, in a moment, be taken off 
and used Zi a common lamp for carrying ^MUt, 
and, although the tube B is »pt:o, the air du«i uot 



pass up it so as to give il the form of 
Aame. When taken off, the ferrule 
turned up till it doet not smoke, and byl 
that it may be made a light of any p 
consuming a cubic foot of gas per hoor, 
it to one-fourth that quantity, regulotii 
the size of the flame. The three not 
feet to prevent the lower aid of the 
injured, and the oi*emng E is for alU 
filled with oil without reiooving the 
only required when a new wick is put 

Mitf fvh, I&4I, 

ENCAUSTIC PAINTINO. 

fUttiimrd /rampant C3, <j'ki cancUfitA,} 
3. C. Wernxk, of Newstadt, in Germae| 
the following process very efl'ectual in aNl 
soluble in water: — For each pound of wbtfel 
takes twenty-four ounces of potush, wUdh 
solves in two pints of water, warming it get 
this ley he boils the wax, cut into little 
half an hour ; at the end of this time hA 
from the lire and leu it root. The wax &i 
at the surface of the l^tfT in the §omk «( 
sairanaceoofl matter, wSHh bdng tiitanti 
water, produces a sort of tnm |i < p n wbldi h 
wax milk, or encaustic wax, and may ba a|ii 
pictures, f^uniturc, or leather, aftvr hmri 
cleaned them : in an hour after the Applies 
article should be rubbed with a piece af 
doth, which will cause the pictures to ha«* 
effect, and the furuiture to acquire a pccuHac 
ness. Another advontogc of thii pcosil 
wax is, that it can be mixed with aU kiodXli 
and consequently be applied in ■ ringiSB *p 
It is also oseliil to fix water colors. 

The following imporUnt obsenratkma tn 
lated from the Italian of the Cfir 
who has deeply investigated the mi 
but valuable tract, called •' ?': " 
Punica. ' ' The andcnts (ujs : 
to Pliny, used three species v- 
three they used Bre ; so that to pniti 
or with a burning application, (>' 
is derived from a Greek wurd. 

We have never thoroughly known the aatai 
Punic wax, which was anciently uoed, asd 
after all, was the essential ingredient of tb« 
painting in encaustic. The Chevalier prali 
genius and industry of M. Requeuo and M. 
lier, who have also Irenttrd of this iuSjfTl, b 
have not fuUy succeaded in finding out the tt 
of making Che said wax, then quotes the pM 
Pliny on the method of making it. Pmiiet 
modo. He, (see Pliny's Nat. History, 1. tX, 
and asserts, witli many other writers, ttiflt 
Hilit is not the nitre of the modema, pmp 
called, but it ia the natron of the ancieota, 1 
native salt which is found crystallised in Kg) 
other hot countries, in sands rairounding [ 
salt water ; it must not b«' mistaken for the 
of the new nomenclatuce of our College of F^i 
which is the new name of the minenl alkali. 
In the pUins of Lower Rgypt, which wa 
covered by the sea. in the environs of the ■] 
of that country, at Tripoli, at Tonis, u thu 
adjacent parts of ancient Carthage, the natr% 
same natron which, under the name of mi 
Carthaginiuns, according to Pliuy, used in pri 
their wua, is to this day extracted, and benc« 
CiiUcd Putuc wax. 



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MAGAZmE OF SCIENCE. 



C7 




now (mjrf Lorgna,} succctsitely to try 

enU. firtt with three parts of wax and 

UD, and then with four of waji, and so 

uwd twenty parts of white melted wmx 

one of nstron, with ai much w«t«r bi wu 

t to mcU the natron. 1 held the mU' 

Iron veatel OTcr a alow fire, ctirring it 

& wooden spatula, till the two substances 

by rrapormtion, and in clotelj uniting 

bj degrtea «»«umed the rontisteiice of 

tlie color of milk, i remOTed it then 

and put it in the shade to let it harden 

t itself in the op^^n air. ThU natron 

from tbe ley of kali of Malta, erapo- 

a dry ; it may alio be extracted from 

Spain, .Sictlr. Sardinia, and from thnt 

•nd of Tripoli, which may be procured 

difficulty. The wax t>eing cooled, it 

water, and n milkv emulsion rt'§alted 

tliHt which could be made with the beet 

P- 

another pUee« c. 7. 1. 23, girea further 
r the rannner of qbio; cauiitic on paint- 
illi; but nB it cof^cems the antiquary 
I have forborne from making 
:,'ins at these norda, Vt jiarie- 
ca, btc. 
vie of this wax in pointing in cn- 
rsaya, that magnificent and re- 
were made In the apartments of 
ni Battisia Gasula, by tlie Iialinn 
Jintnuio Varcheri. He diasnlvrd the 
when it woa not yet so much hardened 
I to be iKTii reaoluta, as expreswd by 
pan waier. lightly Infuiied with gum 
M of sarcncolla, male incenMf. men- 
liny. He afterward* melted nnd mi:?ed 
rith thii was aa liquefied as he would 
with oil, and proceeded to paint in the 
n*: nor were the color* aeen to run or 
leut ; and tbe mixture was ao flexible 
DcQ ran aaioother with it than it would 
|iriCh oiL The painting being dry, he 
kwttc over it, and rubbed it with linen 
irfaich tbe nolor* actjaired a peculiar vi- 
brifhtneat vrhich they bad not before the 
tthe rubbing had been effected. 

lOUNTAlNS, Ac. IN THE MOON, 
poon is viewed through a good trlc-KCope, 
■ppeon to be diversified Mth hills and 
It thia is roost diacernable nhcu vbe in 
fevnlgbu after the change or opposition. 
ia either hometi or siiHmu, the edge 
of the iUumiDBtcd part is jagged 

lebrated astronomers have delincAtcd 
i face of tiip moon ; hot the moct oele- 
those of llevelius, Grimoldi. Riccioli, 
{ in whi(!b the appearance of the moon 
M in .ts diffiircnt atatea, from new to 

iz ited pnrts which appear upon 

tUe ai'-^.-n nre clir\.itcd tracta, some of 
to very Uii:l ;: ■ «; / liri!. while the drirk 
to be pr rf ' and level. Tliii 

ithnes* parts, naturally 

fts to -ro, ' '117 were imtnenM 

nd tiip namca giren tn thorn, 
^ i^tronomcT*. are founded on 

fiiotx. For Hetvliua diftins^uiAiicd them 
the uamei of the scius on Like earth ; 



whtlc be di:FtJncniahcd the bright purts by tbe namra 
ftf the countriPi and islenda on the earth. But 
Riccioli and Langreni distinguished both the dark 
and Itght spntK, by gi\ing them the namea uf celf- 
bratcd aatronomen and mathematicians, which il 
DOw the general manner of diatinguiihing them. 

That ^e spots which are taken for mountalna 
and ralt<ys are really such, is evident from their 
whadow9. For in all sitoations in which the moon 
i» seen from the earth, the etfTnted parts are con- 
fltaatly found to cast a triftngular shadow in a di- 
rection from the sun ; and on the contrary, the 
caricfei are always dark on the aide next the sun, 
and iUuninated on the opposite ade, which if quits 
conformable to what we observe of hills and vnllrys 
on the earth. And as the tops of these mountaina 
nre considerably elevated above the other parts of 
the surface, they are often illnminated when they 
ore at a considerable distance from the line whirit 
Bf^aratea the enlightened from tbe anenllgbienrd 
part of the disc, and by this means afford us a me* 
thod of even determining their height. 

i'rtfvious to tbe time of Dr. Hencbel. some of 
the lunar monntnioR were considered to be double 
the height of ajiy on the earth : but by tlie ohser- 
vationa of thai celrbrated astronomer, their bright 
is considerably reduced. 

For after measuring many of the most coo- 
fipicuouK proniinenres, he says, " From these ob- 
aervQtiont I believe it is evident, that the height of 
the lunar mountains is, in general, overrated ; and 
thnt when wc. hive excepted o few, the generality 
do not exceed half a mile in their perpendicular 
elevation." 

As the moon*a aurfucft is dtveru6ed by mountains 
and valleys as well as the earth, some modem w- 
tronomers any they have discovered a still greater 
similarity ; namely, that some of these are really 
volcanoes emitting lire, as those on tiie eartlv do. 
An appearance of this kind was discovered by Don 
UUoa in an eclipse of the son, which happeoeil oa 
the 2]lh .Tune, 177H. ll was a smidl bright spot 
like n star, near the margin of the moon, which 
be supposed at the time to be a hole ur Tallcy, 
which permitted the sun's U;ht to shine through il. 
Succeeding observations have, however, led aatro- 
numcrs to believe, that appearances of this kind are 
occasioned by the eruption of volcanic fire. Dr. 
Hcrschel, in particular, haa observed severnl eruptions 
of this kind, llie last of which be has descritwd in 
the Philosophical Transactions for 1787. as follows: 
" On April the I9th, at lOh. Gm. I perceived tbr*c 
volcanoes in different places of the dark part of the 
new moon. Two of iktm are cither ah*eady nearly 
extinct, or otherwise in a state of going to brrak 
out, which pcrlmps may be decided next luiinlion. 
Tbe third i-hows an actual crnptioo of fire or 
luniiuous matter : its lii^hl ia much brightcrr tliau 
the nurleud of the comet which M. Mechain dis- 
covered at Paris, on the 10th of this month." Tbe 
following itlght the Doctor found it burned with 
greftter violence ; and by measnremeni be found 
that the shining or burning matter must be more 
than three miles in dinmeter, of an irregular round 
figure, nnd very sharply defined about the edgea. 
Ttie other two volcsnors resembled large fatnl 
ni-huLT, wliirh appeared to be gradually brighter 
towards the middle, but do well-defined luminoos 
spot could he discovered in them. Dr. Her»ciiet 
adds, *' The appcnmnce of what I ha^c called lbs 
acUial firfi, or cniplion of a volcano, exactly re- 
iwtubled 4 small piece of boxuiug charcoal, nheii it 



I 



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MAGAZINE OF SCIENCE, 



is covrrcU by n very ihtn com of while nshct* 
which frequently adherr to it when it has hoen tciine 
time ignited ; and it had a degrtc of brightnns 
ftboat US 9tron|c as thnt with whicli a coul «uuhl be 
seen (o glow in fair clij light." 

The appearaoce which Dr. Ilrrscbel here de- 
oribfls to minutely, wai alio obserred at the Royal 
Obaerratory of Pah*, abont nix days before, by 
Dominic Nouet, like a star of the siitb roafoicude, 
the brigfatneu of which ocoaaonally increaacd by 
flaihea. Other aitronomcn alao saw the aame 
thing, for M. de Vilieoeuve obaerred it on the 22 nd 
of May, 1787. Tliis volcano ii situated in Llie 
nortb-eaat part of tlie muon. about 3' from her 
cdgCi towards the ifiot called Helicon. After cun- 
aideriog all Uir eircumstances respecting ihrsr ap- 
pearances which have just been mentioned, we rauet 
subscribe to Dr. Uenchd's opinion, that volcanoes 
exist in the noon as well as the earth. 

fTotm r*mliMU*^.J 

POLARIZATION OF LIGHT, 

f ltr§umtsi /mm pnf:e 38. J 
In the tninBTniBsion of ordinary liglit through trans- 
ptrent or refracting bodies, ptiTfectly bomogroeoua 
in their structure, and of a aniform temperiturG 
tiiroagboui. such as pure water, well annealed 
glasa, and many kinds of cryvtallized bodies, as 
almn, common salt, Fluor epar, ^cc, a single beam 
will be refracted singly ; and if we make a pin-hole 
in a card, and place it behind one of these bodies, 
and behind the card a candle, so that the Ught may 
first pass ttroogt the hole in the card, and then 
ftrongh the subject of experiment to the eye, the 
hole will be distinctly seen, and will be perfectly 
•ingle. But in roost crystalliac substances this 
is not the case, for surh usually posoesB the pro- 
ferty of double refractioD, a beam of light passing 
through any of thrm )>eing refmt'tfd into two beams 
of oqnal intensity. This beautiful and interesting 
phanomenon is seen, in an eminent d^ree, in Ice- 
land spar (calcareous spar), in which it was first 
discoTcred. 

f' The gczicral effect Is Men in the above cut. The 
Beit figure is a drawing of a model representing a 
rhomb, with a ray of ordinary light A.\ incidcut 
upon one of its natural faces, and which, in passing 
through the crystal, Is divided into two rays, one of 
^bicfa, CC. being refracted according to the ordi. 
nary wajr; the other. DD, not obeying the same 
law, bat being refraclrtl in an extraordiuary maa- 
aer, ia called the extraordinary ray. 









Now, on analysing these rayi, rillier wit)t a vmnl 
rhomb, or otlier«i>e, which will be better under* 
stood as we proceed, they are fotmd to be pfeckih 
alike in every respect, of the saoBk* cbaraqter, w 
posscaaiag the same properties, but that thaw fp^ 
pertica and character are at right ancica to 
other ; the donbly refracting action of Che 
upon light consisLiug in the aeparatjoo of tfaa 
sets of undulations, or tranarerMl vlbratbaib tf 
which a ray of ordinary light consists ; the rfbo- 
tions of the ethereal molecule, in the ardioary of, 
will be in one plane ; while the vibrations m tW 
ethereal moUxmles, in the extraordiEiary ray, will bt 
in another plane, it right angles to it, aa rrpf»> 
Rented by the last 6gure ; and, if we inpposc 4b 
to tv: a bird*<>eyr view, the vibmtions of C C 
in a borixontal plane, and the vibrations of D 
a per|>eodicuhir plane ; each of which is said 
polariecd light : hence, when tlie question ia 
what is the difference belwern common and 
ized light ^ the reply, accordini; to the imd 
theory, is, that a my of ordinary or common 
whether arti&cial or solnr, consists of two 
undulationfl or vibrations <^ the molecnlea 
ethereal or imponderable medium, which w« 
supposed to fill all space; and that these t 
of undnlations are performed in planer, at 
angles to each other ; but that pol <- 
sists of one set of nnditUrioDS, or 
fonned In one plane. The polan/. iiii<li ui ii^K" 
then, is simply the separation oftlie twu fets of ua 
dulations, or vibrstions, of which ordinary light U 
composed, and thus producing a beam of light ii 
which the vibrations of the ethereal motecoki m 
alt in one plane. 

Now, this separadon. or polarization (u It 
rather iinpro)>crIy been called), may be effect 
common crown glass, either by ordinary 
or refraction, each of which will exliibit 
effects. In order to undcrKtAnd this, let BB 
sent a bundle of pUtes of common glaaik 




that a ray of ordinary light A A may form an to|kl 
of incidence of bG"* 45' with a line p rpcndinU« r 
their surface ; then tlie light reneclc-d, and i 
■ented as passing off at D, will be. pnUrixed 
and if a proper number of pUtes, which, 
same angle of incidence. Is 27, be exnplc 
light transmitted at £ will be polarixod alio, « 
rays possessing the some projwrties, bat at 
angles to esch other. Thus, in the reflected 
D, the vibrations are supposed to take phe 
peipendicalar plane, this being a bird's^eya 
wliUst, in the refracted ray, £, the Tibraltai 
performed in a horizontal plane. ThiawUlbe 
understood oo analysing either of tha tays, 
may be done by the some means as tliat by 
the original beam is polarized. Thus, sapi 
we experiment with, or analyse the rtrflected i 
in whieli the vibrations are ia a per)>endicular 
when it is made to foil upon a second bai 
glass U U, at the ssme angle of incidence, 
glass be so placed that the reflection may 
in the same planer ll will again be wholly : 



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MAtJAZINE OF SCIENCE. 



C>9 



•C R B, Kfid xtanc mil be trinsmilttHl or refnictr<l 
frtiiwii the MCOiiJ bumllf v( glnw, for ihr very 
- UiaC prvtiurcd iu reUcflion from the 
■■■Mr; \\t. that thff nbmttons cootinao 
Co the rcficciiug »\XTitct». But if the wcoad 
of glui ii put in tDch a pocitioo that the 
o« ttliaU be performed In s pttoe perpendi- 
to ihe rrrtecliiip iorfjce (whioii may be done 
tamtog it round QU", in such a condition that 
ny of lit^t shall be the uiis npoo which H 
lUwBfs making Ihe sanie angle of ioH- 
) i thfM, MiMon am it begins to torn, the re- 
ft^t ^(11 begJD to deor^je in intensity, uid, 
1 portion will hcf(in to be transmit- 
1 through the glus, ivliich will in- 
rrisc ta lite *Aaie ratio as the reflected light de- 
■ *■» €> i and wht'n the baodht of ghui has turned 
W". in which po«ition we tee it rciprcsented at the 
irfnlVevr rit:w, and at the horiaontal view in the 
t rut, the ligltt D ia wholly transmitted or re- 
frmct««l. as nt CC, no portion being reflected, la 
a |>o«itioo, the vibrations will be in a fUno 
tliieulAT to the reflecting aurface ; and such 
■re always traiiBmtLl«d, and not reflected, 
Hpv has taken place in the polftriKation 
if Am original beam of cooamon light before rc- 
brrrd to. Now let the second bundle of glass II U 




ii> turn, it will be seen that, as soon lu it 

move, the transmitted light CC will be- 

: - ^. a portion beginning sgain to he re- 

:LS the glass turns, will increase in 

l'i[< iamo ratio as the transmitted light 

. until it hfls turned another OO'*, or reached 

<>> die first position, as seen at the next cut, 

wicrvtlte phcne of reflection is again parallel to the 

ftane in which the Tibratiuus take place; cunse- 

the whole light is again reflected at EE, 

£ truismitted. for the same reason as be- 

>J. On contiuoing the revolution, the 

I "^^ 

-1^ occurs at each quadrant of s circle. In 
Al^re, the bundle of gtms H H is roprt>. 
11^ turned 270", or } of a circle. Iii 
the same thing occurs as at 90^'. 
D is wholly refracted or transmitted 
ssa, ai at CC ; bo tliat it is evident, 
-- - , :uicnts, that there ore two positions 
m »tech the same ray of polarized light D is wholly 
i ifl w ^rd. and two other positions in which it is 
' rinamitted by the annlyung bundle of glass ; 
;<ieii af« easily understood, b)' bearing in 
ripiiou uf tlie original ray of ordinary 
z to the unduUtory theory, and the 
I ^t. or polari;tiDg bundle of glsKS. 
- been sUted that a beam of ordinary 
iif a rapid sncces^ion of systems of 
log an immense number of rays, the 
I ■ Ijich are performed in every possible 

^^^^^^miy be aaked, what becomes of those rays, 
^^^^^Hloaa of which are in pUoet iiicliDcd at 



diifer^nt angles between the pcrpcndtcuUr and 
horixoulnl ? Now it is of great importance to an- 
derstond this cU'arly, oa it will aUo nmble tis to uo- 
dcrstand how all the various and beautiful phe* 
nomena of colors are produced. Tlie esperimenta, 
however, which we have been noticing with the 
aualysiug bundle of gloss, will assist as in this ; for 
if we refer amin to Ag. 3, we find that the Tibrations 
of the potnrizetl light D are represented as being 
performed in a perpendicular plane, thot the second 
bundle of glass 11 \l is so placed that such vibra- 
tions are parallel to its ploMe of reflection, nnd that, 
eonse^uentty. in such a position the light is again 
rerlnt^ted, fur the reasons there stated. Now, if wo 
miurk well what follows, when the second bundle ol 
^loss is made to turn round, we shall understand 
what becomes of those vibrations which are inclined 
at different angles, between the perpendicular and 
horizgntol : fur when the second bundle of glass be- 
gins to turn, its plane of reflection will begin to 
form didorent angles with the perpendicular and 
horioontal, and as soon as it begins to move, a |>or- 
tion of the reflected light begins to be transmitted. 
which. OS it turns, increoses in intensity ; and when 
it has reached 4b'', the light D is divided into two 
equal portions, one of which is reflected, and the 
other refracted or transmitted through the second 
bundle of glass, in each of which the vibrations are 
inclined Ab" to the i>erpendiculaT, bnt at right an- 
gles to each other. Thus, in the reflected |K>rtion, 
the vibrations will be parallel to the plane of reflec- 
tion, which is MOW inclined -15^ to tbc perjwn- 
dicuLor ; but, in the transmitted portion, the vibra- 
Cions will be in a plane porpendicular Co the plane 
of reflection, and, of course, inclined 45'' on the 
opposite side of the perpendicular, and, conse- 
quently, at right angles to the reflection portion. — 
It will be understood, then, from these experiments 
that, in a beam oi ordinary light, those rays, the 
vibrations of which are inclined at diflTcrent angles 
between the perpendicuhu" and horizontal, are di- 
vided into two portions, one of which is reflected, 
and tiie utlicr refracted or transmitted, the vibra- 
tions in each of which are at right onglea to each 
other ; but in neither are they in the same plane ai 
in the original ray, tlie reflected portion bring 
parallel to the plone of reflection, and the refracted 
portion being at right angles or perjiendionlar to the 
reflected portion ; and, cooaeqaently, whatever an- 
gle the plane of reflection makes with the plane of 
Tibrations of the original ray, the vibrations of the 
reflected portion will make the same cnglr^ heing 
always parallel. But the intensity of the reflected 
portion will decrease as the angle increases, being 
at its maximum or gre^teAt intensity when pnrallel, 
and at its minimum ur nothing when perpendicular-, 
and vice vcraa with the transmitted portion, which 
increases as the an»le increases op to 90", being at 
its maximum of intensity when perpendicular, and 
at its minimum or nothing when paralleL 

(To be eontinntxLj 



ON PREDICTING THE WEATHER. 

From a very great number of meteorological ohser. 
vatioQs, made in Enghind between the years 1677 
and 1789, Mr. Kirman has deduced the following 
conjectures of the weather : — 

1. That when there has been no storm before or 
after the vernal equinox, the ensuing summer is 
generally diy. at least five times in siit. 2. That 
wbcQ a storm happens from an easterly point, either 



70 



MAGAZINE OF SCIENCK 



on the 19th, 20th, or 2Ut of Marrh, \he ^nccfcAins 
nromer U grnmilly dry four times in fire. 3. Tlut 
when B ttorm arise* on the 25th, 2Gth, or 27th of 
March, Hiid not before, in any point, the succeed- 
injt Buniinrr is generally dry. fuur times in five. — 
■i. If (here be a stonn at S.W., or W.8.W., on Hie 
19th. 2ath. 21st, or 22nd of March, th^ sacceedini 
summer is genemlly vtt fnur times in five. 

To the Ethove we shall adtl the foUntring observa- 
tions from the Eacydopedia Britannica : 

1. A moist autumn with a mild winter, is Rcne- 
r^lyfoUowedhy acold and dry spring, which greatly 
retaurda Tegetation. 2. If the summer bo remarka- 
bly rainy, it is probable that the ensuing winter will 
be serere; for the nnusual eraporotion will hare 
carrried off the heat of the earth. Wet summers 
are generally ntte-ndcd with an unusual (jnantity of 
Mcd on tba white thorn and dog-rose bushes. Hence 
the unusual fridtfidneas of these shrubs is a sign of 
a aerere winter. 3. The appearance of cranes, and 
binds of paasage, early in autumn, announces a rery 
severe winter ; fbr it is a sipi that it has already 
b^tm in the northern countries. 4. When it rains 
plcotiliilly in May, it will rain but Uttle in Septem- 
her, and rice ven£, 5. When the wind is S.W. 
during summer or autumn, and the temperature of 
tlic uir unusually cold for the season, both to the 
foeliiig and the thermometer, with a low harometer, 
much roiu is to be expected. 6. Violent tempera- 
turfS, as storms or great rains, produce a sort of 
rri^ in the atmosphere, which produces a constant 
temperature, good or bad for some months. 



POUNCING DESIGNS UPON CLOTH. 

Thk ordinary means employed in thta art are as fol- 
lotrs : — Uavuig pricked any deaign upon [taper with 
a needle, It is dusted over with a piece uf ninslin, 
contaiuing charcoal very finely pounded and aifted, 
the dujt gets through tlie hrfU-b pricked on llie design, 
and settles on the cloth which La to be embroidered ; 
then with a black or white pencil, according to the 
color of the cloth, the marks left by the charcoal- 
dust ore exactly to be followed. 

The person who docs this ought eitlier to possess 
a knowledge of drawing, or else to have much adroit- 
fieas, in order that the fonii of the deaign may be 
exactly preserved ; but often before the pattern can 
be finished, the dust tlica^off, and thus occasions 
much eaibarrafwoMmt to the workers. Messrs. 
Revol and Kigoudet perceiving all the ilifficulties 
which attend this method of proceeding, have sought 
for, and at length ingeniously contrived a remedy ; 
and the patent which they obtained for their inven- 
tion having expired, we shall proceed to describe the 
means they employ. 

Previously to this progress no means of fixing the 
dust upon the cloth had ever been ascertained, and 
every person wlio was employed in this work was 
obliged to trace n-ith a pen or pancil the design 
formed by the dust, which not only occupied a great 
part of their time, but often ocouionttd Diisttakc;^ in 
the figure to bo embroidered. The new mcthad 
poaaesses the advantages of being able tu cunvry tu 
the cloth the exact figure of the design, and ftu4U- 
tates the progress of the embroiderers, allowing them 
to attain the greatest exactitiide in their work, and 
sparing them the trouble and time they had em> 
ployed in retracing the design. 

The method of |irep&rin^ the composition of the 
powder for pouncing in black, is as follows ; — 
_ Place an earMrw j»ot_over the fire, and put into it 



n given quantity of gom mastic, adding thereto oar- 
thirtieth part of wax, oil. tar, or pitrh ; wlieu ihtt 
is melted, throw into the pot as much tamp-blark is 
may be deeded neoeasary for the color of dw 
pounce, stirring the mixture all the time with an 
iron fpoon. When all is well mixed, take It ftiM 
the fire and povr it into sheets of paper, with d« 
comers turned np to prevent Its ronning over, 1x4 
when well cooled, pound and sift it, and enrioM % 
in B piece of muslin. Pounce with thia wfaafiesv 
design it is intended to form nfKHi any kind of eta^ 
and then it is instantly to be fixed on the ctodt, 1)f 
pusnng it ower a pan of coals of a gentle heat, or Vf 
going over it with a hot iron. In thia latter cttt, 
it La necessary to put a sheet of pB]>er between tie 
design and the iron ; then the design will remain in 
the doth neatly and correctly. 

7>) mate a Wftite /^nerfer. — Take a kaomm 
quantity of gum mastic, and melt it in a glased 
earthen pot over a sk)w fire ; add to this 1 -30(h 
jiart of virgin wax, and when the whole Is meltMl, 
add as much fine white ntver as the gum and «a 
will imbibe, taking grett eare. all the while, 
it in proportion aa the white ia added. Tbe 
when well mixed, must andergo lbs sk 
as black powder. 

ELECTRICAL EELS. 

Thb rivers and lakes of the lowknda of Vcnesiote 

and Cnrnnca are taU of electrical eels, cdled by At 

Spaniards treniblador. (the tremblfr"^ — ' 

French colouibts of Guyanne, the 

These ecla hare Uie astonishing £b > 

their prey by a discharge of clccl^ical matter. 

arc found also in the small ponds or fioota intit* 

spersed in the vast plains lying between the Oronoott 

and the Apura. 

The electrical eel is commonly about six i 
The structure of its nervous system haa 
scribed with sufficient accuracy ; but what 
said of its cellulary rcserroirs, and the 
of its electrical batteries, is purely ima^nwy. 
sensation occasioned by the shock is extremriy) 
All ; and in the paits affected it leaves n ni 
it resembles u sudden blow on the bead, d 
the commotinn produced by the ordinary 
fiuid. The Indians have to great a terror 
animal, and such a repugnanoy to oosnoaBH 
living, tliat Mr. Humboldt had the greau^t i 
in procuring some of them for maki: 
For this purfKjse he atjiid seventi 
Apnra, in the smalt village of CalohofOr 
learned that there was a great number of 
eels near this river. His landlord uadi 
to procure a number for him in vaio. 
Mr. Humboldt resolved to go himaetf to^ 
whuA duMe eels inhabit. Mr. Hnmboldl 
companions witnessed amidst the abodei of 
a sight altogether new and extraordinary. 
thirty moles and horaes had been havtihr^ 
togeiher from the neighbouring an. 
they Live in a wild state in so gre-A' 
the proprietor, when he is known, ] v 

for about seven shillings each. Th" In-'n 
rounding the mnlca and horaes. drovr •:. 
water, and prevented them 5vm re: 
by means of harpoons, ailixrd to t 
bamboos, which they pushed forv 
animaU with loud vocift ration. T, 
or pymrio/i. roused liy the-noiatf anu ttL'r.uir. 
up tu the sarfooe of the wvtan i and swlnntl 



MAGA2INE OF SCIENCE. 



71 




livid teipenui, glide ander the bcUiea of 

aud bone, to whom they couitnuiiicfite 

JBiotions the most sudden and violent. Tbo 

Inipeds, in erreat Agony* their hair tCaj)diiig on 

and theit eye* rolUug wildly with p&in, moke 

lA for their t^ropc in Tiiin. In leas than fire 

of the hoFMi wen dnwa ander thewn- 

)vmed. Vtctory eoemad to be decJuwl on 

of the electriea) eeb ; but their activity 

, and Ungaiih : btigned by the repented 

thax acrvout^etgf, they lannched the 

^" ' m frequently, and with less effect. 

bad cacaped destruction gradually 

atreagth ; and in about n qujutfrr of 

retired from the combat^ in snch a 

tor and exbauction, ttiat they were 

bo land, by means of anaU hivpoona 

to oords.— JEfiMiAtMf'a 7Vae«<r. 

K7OTH OP VARIOUS SUBSTANCES. 

^pmwiE found the following wdgfata reqaiaite 
^Bf acabical inch of the undermentioneil snb- 

K Efan 12«llbs. 

■ WhiteDcal 1928 

■ BocliihOikk 3860 

^^ Portland Stone .... 620 

Crafleith Stone 8688 

of a quarter of an ineh, of diflierent metals^ 
" by the foUowing weights ; — 

Cast Iron 077^ lbs. 

Cast Copper 7320 

FfauYeUow Brass 10306 
Wrought Copper. . 6509 

Cast Tin 966 

CaslLesd 483 

iooa calculutions have been made by Mr. 
dTil engineer, on the comparAtive tens* 
metal*, in the pare nnd alloyed sLitc. 
"If I take copper, whose tenacity or 
the square inch is 12 tons, 1 5 cwt. I qr. 
and to six parts of it Slid one of tin, whose 
I ton, ISewt. 2qrs. and 16 lbs. finite 
ttild tell me 1 should weaken the copper 
If 10 cwt. 3 qrs. and 7 3-7 lbs., instead of 
Dl^ I add 11 tons, 15 cwt. 3 qni. and C lbs. to 
or strength, as eipcrimeut deiiiouslrates ; 
lake three parts of tin, and add to it one 
weakest of all metals, it^ tenadtj or 
the square inch, being only able to 
Sqra.ftud 2.11bB., mere humou reason, 
il calculation, would tell me the 
would carry only I ton, 11 cwt. 2 qrs. 
inataad of which they will carry 4 tons, 
B tb»*» which actual experiments de- 
Sow hami Hating this to the knowledge 
aQ Ida ehemioal researches I How lit- 
kaow or comprehend of the secret work- 
t" 

foree of metals is very much in- 
kwninering or rolling them. To draw 
rkadrieal bar of iron, of M inch dia< 
a force of 43 tons ; while a bar of 
LAmIi ifamrirr. and whose cubic admeasure- 
bi|||^i)l as mach as the li-inch,] requires a 
^^^^to <• draw it uander ; and if we take 
PIBlKaf an inch diameter, which boa been 
Vli 4rawn lo repeatedly, in reducing it to 
le shAlt find that it will require a force of 
it asunder. 




ON THE IMPORTANT USES OF SODA. 

Paw artidea are of greater importjuice to the arts, 
manufiictures, and domestic economy, than soda. 
It is essentially neceasary for making hard soap, 
and forms an excellent substitute for that article ; — 
as four ounces of the former, and six of the lattOTi 
arc fully equal to sixteen ounces, or one pound of 
soap, in washing, white it softens the hardest wnter, 
making a sahng of from one-third to onc-haU die 
expenac, according as the operation may be |>ef- 
formed by hand, or by a maebiae. In the oleansiiw 
of worsted or flannel, the effects are fully evinced, 
which, when managed with worm water, soap, and 
potash, acquire an unpleasant odour, and ore apt to 
Bhrink, in consequence of the rubbing, particuUirly 
if they bo immersed in eold water ; wherots, by 
using the fossil alkali, these ioconveoiencea are said 
to be completely avoided, and neither the quality of 
the goods will be impaired, nor the hands of the 
women be injured in the same manner as generally 
happens with the oommon ley. 

As frequent bathing or washing of the body greatly 
conduces to health, it has been recommended to 
dissolve, in the water so employed, a small portion 
of soda, or to wash with a towel wetted with a solu- 
tion of soap and soda, which opens the pores, and 
removes the unpleasant odour arising from profuse 
perspiration ; a sioiilar spplication will be pro- 
ducdve of equal advanCagcs to horses that are em. 
ployed for racing, post chaises, or other purposes 
where great exertions are required. 

If a weak solution of Bodn be poured into fool 
bottle or casks, in which wine has been kept a con- 
siderable time, it will completely dissolve the crust 
of tartar which adheres to the Inner surface. Root 
tops, saddles, or bridles, are efTcctuolly cleansed by 
a solution of soda, preserving, at the same time, 
the original color of the leather. This alkali may 
likewise be employed for sweetening kitchen uten- 
sils, and particularly for removing grease or adda 
from copper vessels; because these concretions, 
when suffered to remain, form a strong poison, la 
a umilar manner it is used for tin and iron vessels, 
to keep them from becoming rusty. Utensils of 
the dairy that acquire an unpleasant acid smell, 
during the summer, and particularly aiter a thunder- 
storm, though every attention be bestowed upoa 
them, such fetor may be completdy removed by a 
small portion of soda, which will render the milk 
vessels perfectly sweet; Awhile it neutralises and 
dispels the acid ferment imbibed by the wood, which 
would taint the milk. The crystals of soda are not 
less osefol in a medicinal point of view ; a solution 
of it forms an excdlent gargle for cleansing the 
throat, mouth, and gtims, both in a sound and in a 
deceased or ulcerated state; while it whitens the 
teeth, and dissolves all iocnstationB that may be 
formed on their surface without injuring the enamel . 
And, if a small quantity of this liquid be occasion. 
ally swallowed, after washing the fauces of the 
throat» it is said effectually to remove a fetid breath. 
Soda is, in many instances, preferable to magnesia, 
(or correcting acidity in the stomach ; nay, it is- 
even asserted, that it prevents the gout, gravel, 
stone, and similar disorders ; hutly, tf the alkali be 
mixed with cream of tartar, in the proportion of 
fourteen parts of the former to twelve oF the latter, 
it furniahes one of the mildest laxatives, oamelyp 
the ilucheUc salt. 



72 



MAGAZfNE OF SCIENCE. 



IFaUkerat 



Loaooa ... 
Ovm-iH . . . , 



Jperaget^tMfjtttmgeqfllu Quantity (ff 



Thtrmomeltr. 



an 

MIC 



NOTES ON TRB MONTH OP JUNE. 

— Bugloo— Borage^MoUda— Mallow^ HoasulV 
tongue, not forgening 



Btirvmrter. 



tt-VS 
MM 

B0«6 



Jbin. 



33S LaciL 
O-ACO 



Trb ^rigoar ftnd fmhncM of May is now more fully 
eouftriiied, and without jet yieldiug to the languid- 
iWMof th« sultry month* of Jtily &iid August ; the 
young of animdlfl sport in the glade, and luxuriate in 
Uw grusy snd Aower-enamelled fielda. VegetAtion 
no longer appears nipped with cold, and the gardener 
DO longer findi it neocsary to ahield his plants from 
dw aUgfat frosts vrfaicfa he had reason to apprehend 
in tbo bit month. May hna been called the Venus 
of the mBona — June tlie Apollo — 

•• Th« ratuly benuly vt the year. 
Like Ui« (inrd (jod of Il«l«-»liin!." 

AMIHATBD NATUBB. 

If there are lingering songsterv who bare not 
bdisre viiited ut, the first week of the month will 
bring them ; and thoae which pursue ttieir prey in 
the long evening cnn scarcely bo aaJd, before this 
time, to have completely thrown off their' toriiidity, 
and to rerel iu the blandnesa of the bright seaaon. 
Hie Sedge Sparrow and the Fly-catcher we may not 
before have seen. Tlie vnnous OwU and Bats ore 
now toore active and frequent. The smaller birds 
hare hatched thdr young, and are teaching tltem to 
provide for tliemi^clves ; tlic larger fowl are not 
generally so early, nor are the bird£ of snmmer poa- 
sage. It ia not till near the close of the month, 
that the Partridge, the Riil, the Pheaaant, the Lark, 
and the Gronae, have completed their neata and 
hatched their egga — ^having waited for the gross to 
grow and the earth to become somewhat dry, be* 
fore they ventured to by their egga. Nor are the 
Swallow tribe more early, althoagh their habitation 
b ao different. Towards the end of the month, the 
fingtng fairda gradually retire to the woods, and, ex- 
cept the Nightingale and a few others, leave olT their 
charming melody. 

The insect world b all alive ; Bees iwarm— Wasps 
and Hometa abound — and numerous ijieciesof But- 
terfly, Moths. Beetles, and Flies, make their ap. 
peacBooe. 

TBDBTABLE LIFE. 

The flowers of the wild and waste arc inftnttcty 
more absadont now than In any other month ; by 
the botanist the hut week of thu month and the 
first of the next are more to be regarded than, ])cr- 
hapa, any others throughout the year. To enumerate; 
what plttuts he may ordinarily find would occupy 
much space. It may suffice, perhaps, to draw his 
lUentkm particularly in the tnirly part of die month 
to tbe Sedge tribe, and to the Orchideona plants, and 
nther bter to the family of the Grasses, the Urn- 
belliferous plants, and the Rotes, and to collect the 
loaves of Ihoae Willows of which he may previously 
have obtained tho flowers. He will be aware that 
it u not till bte in June that he will find many of 
our alpine or northern plants ; the mountain regions 
are too cold to offer him most of their little beauties 
earlier than this. Tlic plants of the valley are, 
however, rich and varied — he will find the Goat's- 
bvard — the Pimp«iiel — Clover, in it6 various kinds, 
—Wild Thyme — the Pheasant's. eye — the Scabious 
—the Poppy — Larkspur — Corncockle — Greenwccd 



** Tba HoDtyncki« say. 
Waked by Ul« •«rU*r tirtath vl wiiy. 

and hundreds of other pUtiLs equally 
many of them more plcntihil thui thuae 
enumerated. Tlte Yellow Violet, and tho 
green Ladies' Mantle clothe the hilk of Dei 
The Fern or Brake fills the thickeU and 
commons. The meadows are yellow with 
tercup. The woods of Kent abound witli tlie 
tribe, and the hedgcf everywhere with the Ha 
the lloae and the Privet. 

The Water |JantB, the tribe of Labiatac, inclaAn{ 
the Mint, Thyme, ike. for the moat part bcion^ to 
a later seusou. Yet some of them towards thsetU 
of the month may be found in perfection, |iarilc»' 
lady the Y'ellow Iria, which bo much abounib k 
many of onr ditches, and on the river benka. 

CARDKNIXG OPKnATIONS. 

The tearan for lowing, for summer nee. is dm 
over, except, perhaps, a few bte annnab. Bat B | 
the early part of the month the gardener w 
avail himself of any showery wemier to 
various of his crope ^particulariy flowering 
and biennials. HU main attention, however, 
rected to preserve which lie baa before 
watering the smaller kinds, unmoving sucker* 
his fruit-bearing shrubs ; training and trim 
the summer shoots of hu espalier treest end 
ing and destroying insects. In the kitchen 
ment, hcwill still sow Beans, Peas, and 
a bte crop, also Carrota to be drawn youngs. 
will also sow Endive, Brocoli, Savoy, Cu 
for pickling, and other crops. Late m Che 
is the proper season to propogate nuuerxjoa 
ahruhn, trees, &c., by cutting*. Tlius. 
Camationa most be piptnl ; the rvuts of 
Thrift, Gentianella, \c. must be divided and 
out, and slijn taken from the Lavender, tfie 
mary, the Southernwood, and numenna of 
herbs. Those half hardy annnab wUdi 
raued by artificial best, may be removnd 
borders, as soon as tiie Mulberry conoes \attt 
which is ronaidercd hy thi* gardener as a sign 4 
oisual frosts and cold wincb having bft us fat 
season ; this, therefore, affords a crHrrien 
merely for him to remove his tender stnnnals to 
open grounds, but warrants him to bring hi» 
house planttt into the open garden, that their 
ties may add tu tliose of the genonl partecnk 
gardener will not foi^ct abo to take his 
roots from the ground, and to keep thcnt dry 
autumn, well knowing that be diert-hy m; 
increases the vigour of their growth in the 
season. He will be careful abo to take 
them all olTeetB, tliat the snp of the parent 
be too much absorbed by the offspring being 
tached to her. Ranuncalus and Anemony 
ahonld be taken up as soon as their leaves 
All these bolbs and tubers may be ki-pt woU as 
shelves, or buried m dry sand or sawdi 
roob, if large, not touching each other, 
anming of the fruit trees is now over, and 
dener is afaeady looking forward to Us «rUer 
of Strawberries, Raspberris*. Cherriec, 
Potatoes, which shotdd be in the market 
open ground during the third week of June. 



LoiiDOM :— rnnled >•> O KmaxcI", 6, While ilotM tAur. Mik ]£ud--^rublul)rd by W DaiiiAtN, 1 1, l*«Utiiv«Ui 



riH^llMi 



THE 



AGAZINE OF SCIENCE 



^nD Sc&ool of ^m. 




MAGAZINE OF SCIENCE. 



REFRACTING AND REFLECTING TELES- 
COPES. 

AttrAnomicni TeUwcopf. — Th«t this trie scope wm 
Enrentrd in the ihirteeoth century, and perfectly 
known to Roger Bacon, and tbit it wu used in 
En^Und by L^nard and Thomas Digge« before the 
time of J&nsen or Gtlileo, can soLrccIy admit of a 
doubt. R is rcpretented in fig. 1. It consists of 
two eonvcx lensfs A B, C D, the former of which is 
called the objnt glau, from its being next the eye 
E. The object glass is a lens with a long focal 
diiCAnre; and the eyeglass is one of a abort focal 
distance. An inverted image O of any dlttaot ob- 
ject MN is formed in the fwms of ibo object glass 
AB *, and this image is magnified by the eye glass 
CD, in whose anterior fooos it is placed. By trmc- 
ing the mya tbroogh the two lenses, it will be seen 
tlwt they enter the eye at E parallel. If the object 
M N ia near the observer, the image O will be 
ibund at a grwlter disUnce from A B ; and the eye 
glass CD must be drawn out from AB to obtain 
distinct vision of the image O. Hence it is usual 
to fix the objert glass A B at the end of a tnbe 
longer than its focal distoocc, and to place the eye 
glass CD in a small tube, called the eye tube, which 
will slide out of, and into the larger tube, for the 
purpose of adjusting it to objects at different dis- 
liuiees. The mngnifying power of this telescope ia 
e<)ual to the focal length of the object glass divided 
by the focal length of the eye glass. 

Telescopes of this construction were made by 
rampani Dirini, and Huygcns. of the enormona 
lengtli of 1*20 and 13G feot ; and it was with instru- 
menis 12 *ind 2i feet long that Huygens discovered 
the ring and the fourth satellite of Saturn. In order to 
use object glasses of such great focal lengths with- 
out the incpmbrance of tubes, Huygcns placed the 
object glass in a short tnbe at the top of a very long 
pole, so that the tube could be turned io every 
possible dirrL-tion upon a ball and socket by means 
of a string, and brought into the same line with 
another short tube containing the eye glaas, which 
he held in his hand. 

A« these telescopes were liable to all the iropcr- 
ftctions ariffing from the aberration of refrangibility 
and that of spherical figure, they could not show 
objects distinctly when the aperture of the object 
glass was great ; and, on this account, their mag- 
nifying power was limited. Huygcns found that 
the following were the proper proportions : — 



rocal Irogth 


Arwrttkre of 


Foral Icngtb 




«r the objsct 


the olivet 


of (ti« eya 


Magnlfytag 


,!!•.•». 


K «!*» 


tiJ: 


l>offvr. 


1 ft. 


Ohib in. 


0*605 


20 


3 


0-94 


104 


33i 


6 


1-21 


1-33 


44 


10 


l'7l 


l-gfl 


62 


90 


3B< 


420 


140 


MO 


5-40 


5-95 


197 


120 


5-30 


632 


216 



In the artronomical telescope, the object, O, ia 
llwnys seen inverted. 

Terreitrial Tf>i*$cope.—To accommodate this tele- 
•eope to land objects which rrqnire to be seen erect. 
the instrument is eoostructed as in fig. 2, which is 
the same aa the preceding one, with the addition of 
twobnsea EP. GH, which have the same focal 
length ns C D, and arc placed at distances equal to 
double their common focal length. If the focal 
lengths sre not «iual. the distance of any two of 
them must be equal to the sum of their focal lengths 



In this telcacope tlie pn^ren of the riyt is exacllf 
the same as in the aatronomioil one, aa ftv aa L, 
where the two pencils of parallel raya C L, L 
cross in their anterior focus L of lite aecood cyr 
glass E P. These rays, falling on E F, form, in ttt 
principal focus, an erect image 0» which is sea 
erect by the third eye glass G H. as the rayt. dJTa|- 
ing from O in the focus of G II, enter the eya fei 
parallel peociU at E. The magnifying power «f 
this telescope is the same oa that of tha foriMr 
when the eye glasses are equal. 

Galilean TV/mco;??.— This telescope, which is Iha 
one used by Galileo, differs iu notlung from the a^ 
tronomical telescope, excepting in a concave <yi 
glasa C D, fig. 3, being substituted for the coma 
one. The concave lens C D is placed between the 
Image O and the object glass, so that the image if 
in the principal focus of the lens. The penefl ot 
rays ABO, A fi P fall upon C D, converging to 
its principal focus, and will, therefore, be rrfractal' 
into parallel lines, which will eater the eye al & 
and give distinct vision of the object. The 
fying power of this telewope is found by the 
mle as that for the astronomical telescope ; it 
a smaller and leas agreeable field of view th< 
astronomical telescope, but it has the advaui 
showing the object erect, and of giving more 
vision of it. 

Grepon'ttw HrfUciim^ TkUscope, — Father 
ehins seema to have been the first peraoo who 
niied objecta by means of a lens and 
•pecnlum ; but there is no evidence that he 
itructed a rcHrcting telescope with a amaU specnlia. 

James Gregory was the first who described 
construction of ihit instrument, but be doe 
seem to have executed one ; and the honor of 
this with bis own hand* was reserved for Sir 
Newton. 

The Gregorian teleseope is shown in fig. 4, 
A B ia a concave metnllic speculum with a ! 
its centre. For very remote objecta the 
the specnlnm should be a parmbola. For 
ones it should be an ellipse, in whose farthv fccV 
is the object, and in whose nearer focos it At 
image; and, in both these eaees. the wptati 
would be free ftrom spherical aberration. Bnt* 
these cnrrea cannot be communicated with 
to specula, opticians are ntisfied with gi 
them a correct spherical figure. In front of< 
lai^e ipeeulum ia placed a small concave one 
whioh can be moved nearer to and farther froB tke 
lai^e apecnlnm by means of tlie screw W at tto 
side of the tube. This speculum should havt It 
curvature an ellipse, lliough it (a generally ■ 
spherical. An eye-pie^:e consisting of two 
lenses. E, P, placed at a difUnce equal to hall 
sum of their focal lengths, n scrvwi^ into the 
immediately behind the great speculum AB, 
perroaneotly fiaed in that position. If rays 
N B, issuing nearly parallel frum the estremt 
a dtitsnt object, fall upon the specolnm AB* 
will form an inverted image of it at O. 

If this image O is farther from the small 
lum C D than Its principal focas, an inrerted 
of it, P, or an erect image of the real 
since O is itself an inverted one, will be 
somewhere between E and F. the raya 
the opening in the speculum. This image 
have been viewed and magnified by a conraa 
glass at P, bm it ia preferable to receive the 
verging rays «pon a lens E, called the field 
which hiutcus their conTcrgeneOr aod fbnnj 



MAGAZINE OF SCIENCE. 



of to the (bcus of the leni F, by which 
thef are micjmfied ; or. wliac U the same tbtn;^, the 
pcBCilc tlivergitif; from (.he imiiii;*' P arc refracted by 
r, r» at it» enter ihe rye pnmllel, and ^ive dintinct 
of the imaiiT'. If the object M N ii brought 
Cbe «|>eeulain A B, the imof^e of it, O, wilt 
front A B and approach to C D ; and, ood- 
MMHitty^ Cbe oiher image P in the conjugate foca« 
ViC D will recede from iti place, and ceaie to be 
MHO diatinftly. In order to reatore Jc to iU place, 
we have only to turn the screw W, «o as to remove 
D D fiirther from A B, and, conaequentty, farther 
rmn C), which will cause the imn^e P to ap|»ear 
If 4iaCiDct as before. The niacnifytcg power 
tdeaoope may be funud by the followiog 




the focal distance of the great speculum 
of the small mirror from the image 
MrtChe ejt, •« formed to the anterior focuii of the 
lOVVTz eye ghms, aod multiply also Che local du- 
jance of Che small speculum by Che focal disUiure of 
he eye glaaa. The quotient aiuing from diviiUng 
h* fenoer product by the latter, will be the nug- 
|Mns power. 
■Bb nk auppoiei the eyc-picce to couaist of a 

pRt foUowiug Ubk, showing the focal lengths, 
fncrers, and prioe« of some of SluHt's 
•III exhibit the great superiority of le- 
to refrtcUDg ooea : — 

powcn. 



tibs 



Aprrfun* 
tfi inrlw*. 



I 



30 

-4-6 

6-3 

7-6 

12-2 

16-0 



35 to 

90 
100 
120 
200 



lOO 
900 
400 

500 

8D0 



300 1200 



Prtusbi 

u 

3r. 

7r> 

100 
3O0 
800 



CatMifraiiuOH TeitKope, -~ThB Cass^miuian 
■ksonpr, proposed by M. Ciissegniin, a French- 
|WB< didfcrs iTom the Gregoruin only in having its 
m»lk apeculum CD, &g. 5. convex insteul ofcoa- 
ttvcL Ttie spectiliim is, therefore, plaoed before 
h'* tmi(^ Pof the objeec M N, and ao erect image 
' ill be formrd at O between E aod F ex- 
i> the Gregorian instrument. The advsD- 
a^e 4t[ UL> form u, tiiMt the telescope is shorter 
Ian ih# Gregorian, by more Chan twice the focal 
■■gth of the louill speculum ; and it is generally 
(fasitted that it gives more light, and a dijilinoter 
!, in conivqaence of the convex specujom cor* 
tibe aberration of tbe ooDcave one. 

7>/#«co/*e.— TbeNewtouiao telescope, 
Bay be regarded aa an improvement upon 
IvOnsoiisa one, ,ii represented ia 6g. G, where 
iB b a ooncare speculum, and O the inverted 
Mfe which it forms of the object from which the 
kytMN proceed. As it is impossible to lotro- 
htpBthe «y« into the Cube to magnify thia image 
dikolU obsCmoting the light which comes from tbe 
IIiIhU a acoall |»Lsne speculum C D, inclined ii'^ to 
Mob of tho Lai^e speculum, and of an oval form, 
hMM boiag lo one anotlier as 7 to 5, pUced be- 
WB ttw apeculum snd tbe image O, in ord^r to 
|dHt It to a aide at P. so that we can magnify it 
lllh OA fff* glass E, wtiicU causes the rays to enter 
t#4]ia pttnlleJ. The small mirror i* lixed upon a 
(■der arm, connected with a slide, by lihich the 
ibror may be made to approach to, or recede from 
Itlwg* specnlom A B, according as the image O 
to, or recedes from it. Thia adjust. 




ment miglit also be elfectcd by moving the eye Imts 
E to or from the small spccitluui. The magnify- 
ing power of this tdejcoi>e U rt|ual to the focal 
Icagth of the great ipecuLum divided by thitt of th« 
eye glass. 

Aa about half of the light Is lost in metallic re- 
flexions, Sir Isaac Newton proposed to subsHtttle, 
in place of the metallu: speculnm, a rectangnhir 
prism, in which the light suffers total reHexion. — 
For thiti purpose, however, the glass is required Co be 
perfectly colorless and free from Tcins, and hence 
moh a prian boa almost never been used. Sir Isaac 
also proposed to make the two faces of tbe prism 
convex, and hjr placing it between the image O and 
the object, be not only erected the imsge, bat wu 
enabled to vary the niagnilying power of the teles- 
cope. The ohgiiul iclcscope, constructed by Sir 
l«aai:'s own bauds, is preserved tu the Ubrsry of the 
Royal Society. 

The following t«ble ahows tbe dimensiona of the 
Newtonian telrjH'opes, which has been computed by 
taking a line telcscojie made by Hawksbee, aa a 
standard : — 



FiK-al len|[th 
of BTvst 
■IMrruluoL 

1 ft. 

3 

4 

6 
12 

24 



Aperture itf 
ipcculuin. 

2-23 in. 
3-79 
5'U 
6 56 
8*64 

uao 

24*41 



Tocal length 
of ey« gt£n. 

0129 in. 

152 

0168 

0181 

0-200 

0-2.18 

0-283 



tfSgitirytng 
|w«»r. 

93 

214 
2fiA 
360 
601 

10171 



On account of the great loss of light in metAlltc 
reflexions, which, according to the accurate expert- 
ments of Mr. R. Potter, amounts to 45 rays in 
every 100, at an incidence of 45^. and the imper- 
fections of reflexion, which, even with perfect iiur- 
faces, makes tbe raya stray jfSre or rtx times more 
than the same imperfecHoik^ in refracting surfaces. 
Dr. Brewster proposed to construct tbe Newtonian 
telescope, as shown in fig. 7. O ia the imsgc of 
the object, C D an achromatic or double pri«ai, 
which refracts tbe image O into au oblique position, 
so that it can be 'jk'iewed by tbe eye at E through a 
magnifying lens. Nothing more is required by the 
prism than to turn tbe rays as much aside as will 
enable the observer to see the imnge without ob- 
structing tbe rays from the object "M N\ As the 
prisms of crown and flint gl'iss which compote tltr 
achromatic prism may be crmcnted by a substanrtT 
of intermediate refractive power, no mure light will 
be lost than what is rellected at the two surfaces. 

In place of setting the small speculum, C D, of 
tbe Newtonian telescope. Fig. 0, at 45", to the ind- 
denC rays. Dr. Brewster proposed to place it much 
more obliquely, so as to reflect the image out of 
Uie way of the observer, *nd no fartiier- Thia 
would of course require a plane speculum, C D, of 
much greater length ; but tbe greater obliquity of 
the reflection would more than compensate for this 
inconvenience. It might be adviAable, indeed, to 
use a small speculnm of dark glass, of a high re- 
fractive power, which at great ioddeocea reflects 
as much light as metals, and which is capable of 
being brought to a much finer surface. The fine 
surfnees of some crystals, such as ntbyatlver, oxyde 
of tin. or diamond, migbt be used. 

A Newtonian reflector, vjMoh/ an eyt gla»», may 
be made by using a reflecting gloss prism, with on* 
or both of its surfaces concave, when the prism ia 



MAGAZINE OF SCIENCE. 



place*] b«t*reeD tbe itnotge O atij th^grmtspccuhim, 
^M> Bk to reflect the rayi pKraltel to the ryr. The 
ijCnifyiiiK pwwer will he rijiuil to the Uw.n\ lenG;th 
the grent ftyirculum, diTidcd by the rndiua of the 
concftre iurfar« of the prism, if both the furfiices 
Are concave, anil of equal cooeavlty, or by twice 
the radiBS, if only one surface is concave. 

SPOTS. MOUNTAINS, 8lc., IN THE MOON. 

I Hfiunrit from futgf 66. ami cuncludni. ) 
It hitt Ion;; been a disputed point amonf; astrono- 
mers, whether or not the moon is surrounded by an 
nlmo9phere. Tlioie who deny that abe is, »ay thai 
the moon always appears with the some brightness 
when oor atmosphere is cleor, whieh could not be 
the csae if >he were sorrounded by an atmosphere 
like oars, so rarinble in density, and so often ob< 
wmred by clouds and vapours. 

A second ar^ment is, that when the moon ap- 
proaches a star, before she panACS between it and the 
earth, the star neither alters its cdor nor its situa- 
tion, whirh would be the cajie if the moon had an 
atmosphere, on account of the refraction which would 
both alter the color of the ktar^ and also make it 
appear to change its place. 

A third argument is, that as there are no seas or 
Lakes in the moon, there is, therefore, no atmoaphere, 
as there is no water to be raised up into rapoiir. 
Bat those who contend that the moon is surrounded 
by an atmosphere, deny that she always appears of 
the same brightness, even when our atmosphere ap- 
pears equally clear. Instances of the contrmpy are 
mentioned by Hevelius and sonic other sstronomers, 
but it is unneccsBnrr to take any further notice of 
Ihem here. In the case of total eclipses of the moon, 
it ia well knovm that ahe exhibits very ditferent sp- 
pearances, which it ia supposed are owing to cbaugea 
in the stattt of her atmosphere. It ia remarked hy 
Dr. Long, that Newton has shown that the weight 
of any body on the moon is but a third pnrt of the 
weight of what the same body would be on the 
earth, from which he concludes that the atmoaphere 
-of the moon is only one-third part as dense as that 
of the earth, and therrfore it ia impossible to pro- 
dure any aensibic refraction on tlie liu;ht of a fixtil 
star which may pais through it. Other astronomers 
assert that they have observed such m refraction ; 
and that Jupiter, Saturn, and the fixed stare, had 
their cirrntar figures changed into an elliplical 
one on these occasions. But allhaiigh the moon 
be surrounded by an atmosphere of the fcame nature 
as that which surrounds the earth, and to extend 
- as far from her Rurface, yet no atirli effect as a 
gradual diminution of the light of n fixed star rould 
be occasioned by it, at least none that could be 
obMrved by a spectator on the earth. For at the 
he%ht of 4^1 miles our atmosphere is so rnrc, thAt 
it i> incapable of refracting the mys of light ; now 
this height ia only the IHtli part of the earth^s dia- 
meter, but ai douda are never observed higher 
than 4 miles, H therefore followfi thnt the obscnrr 
part of our atmo^here is about the 2000th part cif 
the earth's diameter, and if the moon's apparent 
diameter be divided by this number, it will gire the 
angle under which the obscure part of her atnioa. 
phere will be seen from the CHrth, which w not 
c|Uitc one second, a space passed orer by the moon 
ill less than two seconds of time. It can. there- 
fore, scarcely be expected that any obscurMtion of a 
alar could be obserrcd in so short a time, allhoogb 
it do tilie plar<. 



\» to the orgTuiicnt ogtrlnst a lunnr iitmosplkn, 
drawn from the conclusion Ihnt ih--" 
ttr lakes in ihe mnuu, it proves nc: 
is not pfMitively known whether th- ■ 
in the moon or not. 

The i|Ufrtinn of n lunar •hn«»plM»re wrma t»tfc' 
at lost settled by the mn > acr* 

Tailoni of the relebr -oa 

and Pitni, who have pi-.v'M '<- '"utiTi^inKij «• tla 
nature of the subject seems to allow, that the mam 
has really an atmosphere, though much Lb«s 
than ours, and scarcely exceediiog in lieigbt 
of the lunar mountains. 

It ia remarked by Dr. Brewiter, " Tb« 
scenery of tiie moon bejwv a stronger cetci 
to the lowering sublimity and terrific 
the Alpine regicms, than to the tamer inc 
less elevated connlries. Hugh masses of 
at once from the plains, and raiae their pnltsAi 
summita to an immrnse height in the air. *«hiV 
projecting crags spring from their rogi-' 
and, threatening the valleys below, stMn '-■ 
fiance to the laws of gravitation. Arnnmi the 
of these frightful eminences are strewed nui 
loose and unconnected fragments, «hi<;h time 
to bare detached from their parent maet. and' 
we examine the rents ond ravinca which at 
the overhanging cltfis, we exf^ect every 
that they are to be torn from tbrir base, aM 
the procesH of destructive separation which 
only contemplated in its eficcta is about ta 
hibited before us in tremendous real : ' 
mountains called the Appennines, whid ' 
portion of the moon's disc from north-east i< 
west, Hm; with a pmupitoua and craggy front J 
the level of the Mare Imbmm. In some 
their perpendicular elevation la above foar 
and though they often descend tn a much loi 
th(^ present an inaccr«sible barrier to the 
east, while on tbe^ soatb-we»t they sink in 
derlivity to Ihe plains." 

The caverns whirh are observed on the 
surface are no less remarkable than the roi 
mountains, some of them being three or fen 
deep, and forty in diameter. A high angl 
of rocktt, marked with lofty peaks and tittle 
generally encircles them, on insnUted m* 
frequently rises in their centre, anrl 
contain smaller cavities of the i>::' 
themselve^t. Thrae hollows are mii->> i>»»>r 
the Ponth-wcBt part of the moon, and it 
this cause that this part af the moon ia 
liant than any other part of her disc. Ths 
tainouB rid;;es which encircle the mrT*tr^, 
the greatest quantity of light ; and. '■ 
in every possible direction, they h\ 
time of full moon, like a nQuber ut rmiiu 
diations issuing from the BmiUlest 
Tycho. 

It is difficult to explain, with an^ 
hability, the formatinn nf these inini 
it is highly probable that the cartii wi>uld 
the same figure, if nil the seas and lakes sh 
moved : and that the lunnr cavitie« are eiilu 
tended fur the reception i)f water, or that 
the beds of lakes and seas which have fori 
isted iu the moon, 

The cirruiwtauee of there being no vratvr' 
moon afforda tt strong proof of the tmlh 
theory. 



spot. 



MAGAZINE OF SCIENCE. 



77 



rock, the Mscntiil ingrcdicntji of 
'■nr Mcbpnr, qtivrtx, Hnil w'w.a, htrifiK tlif^ 
Htcmf of gnciiM. frnm whtrh ^anite dilTeni 
Sn the ttrrangrrarDt of thr three companmt 
tlhetr bein^ mingled wttlMtut order or rr^u> 
irodurei b (p^nuUr •cructure, while that of 
imllT slaty. Thi;t ate of granite fur 
■od rronomiral purposec. is p<<rhn|M 
)retDiply diaplajed ttian at I'cterBburgh. 
otily ike imperial and other paUcea, but 
Unary dweiltni^.houanf, have their lowrr 
Tith alalM of ^n^nite. The left bank of 
It Neva, from the Foundry to the Gulf uf 
lA, and both banks of tbe Fontanka and of 
te canal, are lined by high walls con- 
anch slabs of granitf ; a» are ninny 
the Neva, balustmdeti. He. The pillars. 
&c. ID the palocr of Cronnladt, 
an of thr 6nrflt kinda of granite. Thotwi 
for ornameiitol architecture are cut and 
lidariet ; but tbo4e mtenilml for leaa 
i. anch BA coinmoo alaba, ittepa, 
)Ofh<t, SiC. are worked by peaaanta, 
larly bythftfc of Olonesk. The government 
bowc\er, Moscow not excepted, arc too dis< 
the chitrf frranice mounlains. to be enabled 
frFcjoent use of that rock for the above 
Granite haa been more particularly ap- 
ther witli itenite, for the purpoaea of ar- 
and statuary, by the anciratg, eapertally 
'B^ptiana ; and many very interesting mono- 
ir »k)tl and patience arc still exlftttni; in 
of anliqiiiciefl. Mr. Brandc haa di. 
Ivrcnt panitea used in the arts after 
linaat colore ; thr following are the 
in which, however, the black- 
kind ia not included, one of ita in^re- 
ig hornblende, whidi aaaigiia it a place 
ite*. 
1^-Cketti, in the department of the 
ot white quartz and black mica, 
ratals of roae-colored feldspar. The 
tlic KgliM d'Enee (ancirnt tennptc of 
Bt Lyons, are of this kind of granite, 
IBT a1«n hem worked by tbe Romana. 

•fTham, conaiits of grey (juartr. 
\n ^liitc feldspar cryat&la, which are 

tr^ irutn two to three inches long. Tbe 
of (hri« granite are on the roait from Lyona 
loe. nn the rij^ht bank of the Rhone. It is 
11 a<da;iti^il for the eonsCniction of large mmia- 
The t^nmiCe of 6t. Peray, not lar from 
Ik exactly like ihta, except that ita fcldapar 
are M n ni**" color. 

Grr 'zzi, a. atnall island near Bo. 

«w' I, in the straita which sepn- 

isUiKi <i"iii .>>trdinta, ie composfd chicHy 
liar eryitala of feldspar, miierl with a 
«iiea, besides fihich it contains nisu ft>ld- 
ila« of a milk-white color. In the quarry 
B br?T unfinished colnmn is U) be aecn. 
-hed hy the Roman workmen. 
'. — Its Brain is pretty uoi- 
ii*;r«(.m( umeaapproachea to light violet. 
ir r<ilumna of thi« variety to ho *<-en in 
fapttleon ; ihcy were taken oat of the 
contained tite tomS of Charlemagne, 
iprHe. Tbe rrry granites ore mnch 
, ihe green or greenish, of which 
re to be mentioned. 



Antique Gretn Omnih, — Ita predominnnt ingre- 
dient in white quarts, with here and there aomr light 
green feldspar. Itiere is a column of it in the Villa 
Pamfili, near Rome. 

i^ae Grained Autiqut Gmnite. — (Bnaftlt«Terd 
oriental.) Tlie component parta of this aort are 90 
minute and intioiatcly hlendrd, that they can 
acarcely be diatinguiahed by the naked eye. lu 
color Bppronchea to deep ohve. It is very hard and 
takes n tinr polish. The Egyptians have much em< 
ployed it for the construction of monuments; and 
aeveral statues of it mny be si^en in the Capital and 
the Villa Albani. There is another variety with 
white spots, known nt Rome under the name of 
Iltualto OriMttnle pidoehtotQ .- but it is very rare, 
for there are hut two coliimoa of it in cxiatrnce, 
namely, in the rhnreh uf 8t. Pudentiitia at Rome. 
Some vurietin5 bearing that name ore selonite. 

Granite uf St. Chriatophe : composed of violet 
quartz, wliile fcldripar, and green mloa. This n»g- 
niticent rock is found at Oiaaos, in the department 
of the Iserc. 

Cortican Orticuhr Granite. — This beaulifol rock 
(which probably belongs to the sienite formation) 
was discovered by M. Barral, in the island from 
which it derives its name. Its coTn)iOHition m very 
extraordinary ; it has a baeis of ordinary grey gra- 
nite, which, however, in most (Mirts exhibits a con- 
sidirablc portion of hornblende. But what more 
particularly charactenxes it, is a number of baUa. of 
from one to two inches in <bnmeter, each composed 
of sevcjul nmcetttric and perfectly parallel tayera, the 
outermost of which, generally white, opaque, and 
two or three lines thick, is composed of quartz and 
feldspar, blendtMl in variotia proportions, and exhi- 
biting a radiated appearance, rather converginf 
towards the centre of the ball. The second layer, 
which is of a greenish black color, and about one line 
thick, is composed of fine laminar hornbleude ; and 
thia ia anccvedcd by a white and usually translucid 
quartz layer, of about four or five lines in thickness, 
ioduaive of two or three very thin layera of horn- 
blende, that are commonly seen within Uie ^ubsta&oe 
of this third principal Inyer. Kach of these layers 
is generally of equal thlckncM in the whole of its 
circumferenoe. Tht»e three pans may be considered 
as the coating: the interior of each ball is less de- 
fined than the surrounding layers, and consists of a 
blackish and a whitish substance, the former sur- 
rounded by, and posatug into the Utter, the centre 
of which is usoaily a dark grey spot. The quarry 
of this rock is unknown, a singl\? block only having 
been found in the gulf of Valirieo, in Conina : ita 
weight was about 80 lb. ; bat it was soon broke 
into small fragments, which are now distributed 
among collectors. There is a beautiful vn5e of it, 
one foot six inches high, in the cabinet of M. Dedrce. 
Tlie grioiitr uf Corbira is figured by M. Paujas de 
St. Fond, iu his Emai de Geologir, and in Mr. 
Sowerby's Erotic Mineralogy. Among tho red 
granites, we have what is called rtd oriental yranitet 
which usually coDUioe hornblende, often in largd 
separate patches. 

Rfd Granite of Ingria.—^* This granite, ** Myi 
M. Patrin, "is distingaishcd from otbera in this, 
that the fehUiiur, instead of betug in grains, or jwt- 
rallelopiprd crystals, aa in most other grmatea, 
consLantJy appears in the shape of round or oval 
pieces, of from half tin inch to two inches in diam- 
eter. This granite takes a very fine [>o)i»h. and in 
this state exhibits the feldspar in the shape uf white, 
roandr or oval fchaioyaaJj spots, in a reddish 



MAGAZINE OF SCIENCE. 



gToond. The rock, which ierre* m a pedestal of 
the equestmn it&coe uf PeCer the Great, at St. 
Petersburgfa, u of this punite i the block was qH- 
giiiaUjr 32 feet long, 21 feet thick, and 17 feet 
wide i bat, in order to give to ita preacnt sha}>c, 
imitative of a picttirei<iDe uatnral rock, it has been 
mach dintinished in lixe. Thii blotrk vas diien- 
giged from a swamp, about forty veniU from Petera- 
burgb : ilt weight wu calcnlated to be above three 
roillioni of ponndi." We baTo aeen icversl frn^- 
manta that were detached from the yery block form- 
ing the pedeatfll of the statue ; but in none of tliem 
M we obaerve the form ascribed hj Patrin to the 
feldspar. The public summer {irDiorciade-gardea at 
Petersbargh is decorated with a superb colonnade 
of this granite : the columns, which are sixty in 
aamber, arc of the Tuscan order ; their shafU, 
made of one piece, are about twenty feet hif^h, and 
three feet ia dismeter. The island called Kotlin- 
Ostrow, on which is the fortrc«s of Cronfttadt, it 
covered with blocks of this granite, the feldspar of 
which is sometimes uf the kind called Labradorstone. 

Hed Granite of tht VoMgeu MouniamM. — This 
granite ia composed of large laminee of ro«e-cotored 
feldspar, grer grsinit of quartz, nnd small acaira of 
mica. It has so strong a reseuiblaitce to the Egyp> 
tlan red granite, tliat it in difficult to distingoiih 
them. Jta quarriea are on the heii;hta of Moataajen, 
near the Papcan mountains, in the Vosgee. 

VioM (rrtxmie of Elba.— The fcldepar of this 
variety it in large violet (-4'yBtals. TIte pedestal of 
the equestrian statue, in the Piazza della Santisslma 
Aiiiiuttzidta at Florende, is made of it, as alto the 
9itde4 ia the chapel of $t. Laurence in the same town. 

Koge-eotorrd Grtmiie of Sarcno, — This beautiful 
gnuiite consists of fl<rsh>colored feldspor, white 
qDartx, and tome grains of black mica. Consider- 
able quarries of it are found on the borders of the 
Lago Msggiore, which are worked without inter, 
misaion. for aujtplying Milan, ond the whole of the 
iMUghbouriug country, with this granite. It takes a 
tery fine (Kiligli : here and there it rxhibils ribands 
or zoneH, of a grey trolor, which are composed of the 
same ingredients as the rest of the moas, but reduced 
into very minute particlea. Many columot, por< 
tioos, Jkc. are seen of it at Milan. The name of 
ffraphic granite is given to those kinds in which the 
feldspar forms large concretions, intermixed with 
grey quartz crystala, esiiibiling. when cut trans- 
versely, angular, mostly shaped like a 7 ; while 
others are lest regular.and bearadistant resemblaDce 
to rode alphabeticsl writing. They are not considered 
to be genuine granite by some muicrslO|tisti. 

Orcp/iic Granite of P<irt$oy. — ^The feldspar is of 
various tints of psle flesh-red ; the quurti dark, but 
trADiparent, with now ind then some small particles 
of mica. This rook is miiiutdy described by Dr. 
illutton. 

GrapAic Granite of Siberia. — Ita feldspar is of a 
^eUowtih white, or reddtih color ; the quartz, exhi- 
biting figure! sioiilar to those of the quartz in the 
Mvacding sort, is of the variaty called wmokf topaz. 
Mica occurs in it in aniall ncitt, and in acicutar 
crystals. 

Graphic Granite ff Autvn. — Of a pale rose color; 
quartz rryst«ls grey, very ntiinerous ; found in the 
neighbourhood of Autun, dt-piirtment of SJsdne and 
Loire, particularly at Marmagnc. This, in Mr. 
Brand'a opinion, is the most beautiful of all granites. 
Another vsriety of this stone is found at the same 
place : iU frldspar is white ; the quartj grey, in 
•ftiall orystils : it is suscrj>tible of a very fine polish. 



Graphic Granite ^ Cbm'ea.— Lik 
color ; bat generally paler than that ol 
which it is ako distinguisluibte by ita 
being larger, and at greater distanced 
It contains some tliinty disseminaud b 
mica, and lakea a 6ne polish. 

The above givea no •ccoont wImi 
granites which o«r owq islMuto prodal 
the Bore remarkable, as we can bn 
the flneat gmltc in the world, both ol 
the grey species. The fine red % 
from the qtiarriea of Uevonahire ia 
passed in color, clearness, and capabOl 
iiigli fiulish by any other in the worU 
two splendid riilumns of it, each ro 
block, in the King's Library, at the Brl 
which cost i^lOOO a piece. They we 
v&lry to sitnilar columni at Petersbar 
granite pf Ingria, as befiire alluded \ 
these columns arc two equally magni0 
of the grey granite of Aberdeen 
block. The value of thii species to 
be too highly appreciated ; it ia 
which our bridgei and greut boil 
and which broken into fragments of 
nacd to pave the public thorougbfara 
granite, some of which is greyi other J 
is also moch eateened. 



SOLUBLE GLASS 
A suiPi.a silicate of potaasa or soda, 
perfect sulnbtlity in boiling water I 
general properties of common gUsft. 
aute. it may be applied to cloUi or 
pnrpoee of reodcriiig tbetn incomboatih 
by the evaporation of tlic wster in whj 
solved, a hiyer of a subctooee capd 
when heated, is deposited on these bod 
tects them from the contact of air 
combustion. The ibllowing aooooa 
fncture and uses is derived from ■ 
Professor Rcnwick. of the Traxtf dtCk 
oirx j4r/s, per M. Awsuu. 

Preparation. — Soluble glaaa may b4 
dissolving pure silica, obtained by pnd 
boiling solution of caustic potaasa ; bol 
being both inconvenient and coatlf , ci 
tlaed upon a large ooele. When land 
of potaaaa are heated together, the OH 
never wholly driven off, eicept wheB 
excess ; but the whole of the carbooi 
expelled by adding powdered <A«roM 
ture, in lurh proportion that the 
that part of the carbonate whlnh is 
by the carbon, the carbonic oxide 
potaaaa thus freed, either sabUmos, or^ 
the ghua already formed. 

Tbe sand freed from lime and eload 
bonate of potasea (pearlaab) are 
portion of 2 of the latter to 3 of the ft 
10 parts of pearlaah and 15 of s&nd, 4 
coal must not be taken ; ou the oeatiBl 
of potash employed be not stt6&caeoU]r ] 
proportion of charcoal may be advi: 
ployed. Tliis lubatanoe aooderatea 
tbe gloss, find separates from it all thct 
of which there would otherwise renute^ 
tity that would have an injuriooa 
respects, the same precanttons that era 
the manufacture of common ^lasj ve 14 
The materials muat be hr»t wd'i nrt&ed 
and findily melted in a glaaa / lOt, auitll 



A 




MAGAZINE OF SCIENCE. 



M ud bomogtfDcoiu. The melml matter 
t of the pot witb sn iron UiMa, and the 
filed with fn»h frit. Thirty poniMls of 
\ of mod. iDfl I21ba. of poirdered cbar- 
la^eo for a. charge ; with thia quantity 
}mX. be coatinoed far 6ve or lix houra. 
tbiu obCtined U uaoally full of air 
%m ■• hard as commoa glasa of a blaclc- 
v*« and at othera ia jelJowiah or rvddiah : 
■<:atioDa that the quaotity of charcoal 
luffielent. If it be ezpoaed for tome 
Kir, it uiuleq;oea alight changet. which 
> improTe than injure its qualitiea. It 
E^ mouture from the air, which atowly 
^2UM, without changing ita aggregation 
a-zioe ; it merely oncka ; and a alight 
a Ppear* at its aur£u:e. If it be expoaed 
&C have undergoDfl thii change, it iwella 
Ibe ftcape of the aqucoua matter it 
In order to prepare it for solntioa 
it muat be reduced to powder by 
were Dot done, it wonld diiaoUe too 
part of gU»f reqairea from 4 to 5 of 
olution. The water ia firat beated to 
niast be oontinuod three or four hoa rs , 
a l^ass ia diiaolved t the Uqaor will then 
d. the proper degree of concentration. 
tion be citecked before tfata atate ia 
'1>oiitc Acid will be absorbed by the 
Is the air, which will produce an injuri- 
for the same reason, too great a quan- 
ts BRiat not be eaaployed, for during the 
n it will re-Adily combine with the 
\ tiuie a precipitaUon of the silica. 
Uqnor becomes too thick, before the 
|ba« is dissolved, boiling water must be 
ricn the solution h&a acquired the cod- 
p, and a density of 1.24 to 1.26, it 
tratedf and fit for use. It is 
t, in order that the insoluble 
ostted ; wbilc it is cooling, a pel- 
upon the surface, which after a time di«- 
itaelf ur may be rv-dissolved by depres- 
Iw liquor. Tbis pellicle begins to appear 
BbBUllion* and its concentration. When 
^aaa ia of a proper composition it contains 
Aaline imparities, and no snlphuret of 
it nay be created in the way we have 
bot if it contain any notable proportion 
they must be separUed before 
1 1 this separation may be effected in 
\ Bttaner :— The powdered glaas is ex- 
action of the air for three or four weeks, 
tb time in uoiU weather, it must be 
The glaaa, as we hare atated, attrarta 
the air. and the foreign substances 
or eOQoreaoe. It then becomes easy 
tJbvm from the glass. It is sprinkled 
{ud frequently stirred. At the end of 
I the liijuur is remoTed^ it will then con- 
Lhe saline impurities, and a little 
potaasa ; the powder Is again to 
h water, and the solution leaves 
To preserve it in the liquid 
eve is necessary, as even after a 
landerfoes no perceptible change, 
properly prepared. The 
t« allow loo free an access of air 
may be obtained by using a 
inatead of one of potassa. In this 
of the soda of the shops is required 
This gliM hoa ihe aame pro^r- 




lies as the other, but is more valuable in its uses. 
The soluliou of these two kinds of glass may be 
mixed in any proportion whatever, and this mixture 
li more serviceable in aoae caws, than either of 
them separately. 

Propertiet Soluble glasa forma A viscid aolatiaa. 

which when coDcentrated becomei turpld and opa- 
lescent : it has an alkaline taste and redaction, 
TliQ solution mixes In all proportions with water. 
When the density of the solution ul.25, it contain* 
nearly 2S per cent, of glass ; if the ronrentration be 
ouried beyond this point, it becomea to viacid that 
it may be drawn out in threada like molten glnaa. 
Finally, the liquor passes to the sUte of a vitreous 
msas, whose fracture is conchoidal ; it then reaem- 
bles common gloss, except in hardneaa. When the 
solution is applied to other bodies, it dries rapidly 
at common temperatures, and forma a coat like a 
varnish. Soluble glass when dried does not undergo 
any perceptible change when exposed to the air, 
nor does it attract from it either moisture or cor. 
bonio acid ; neither has the carbonic arid of the 
Btmogphere any well marked action on the concen- 
trotyl solution ; but when a current of carbonic 
acid is passed through the solution, the glnss is de. 
composed, and hydrate of silica deposited. But a 
weak aoltttion becomes turbid on exposure to the 
air, and ia after a time dei:ompoaed wholly. When 
the glass ia impure, on efflorescence is formed after 
a while, which may be produced either by the car- 
bonate and byposulphate of potaaaa, or by chloride 
of potoaaium. Soluble glass dissolves gradually 
without residuum in boiling water ; but in cold 
water the solution is so alow as to have led to a be- 
lief that it dues not diuolve at all. It however never 
become! entirely insoluble, except when it eontains 
a much larger proportion of silica, or when it ia 
mixed with other bodies, such as the earths, metalllo 
oxidea, &c., with which double or triple salts are 
formed, u ia the case in the common glasses. 
Soluble glaas which has been exposed to the air, and 
is afterwards snbmitted to the octioo of heat, swells 
and cracks at first, and melts with difficulty ; it then 
losea about 12 per cent, of its weight. It therefore 
contains, even when solid, a considerable quantity 
of water, which it does not lose when simply dried 
by exposure to the air. Alcohol precipitates it un- 
altered from its solution in water. When the solu- 
tion is concentrated, but little alcohol is required 
for precipitation, and it need not be highly rectified. 
Pure soluble glass may therefore be easily obtained 
from an impure solution by the use of alcohol. 
The alcohol being added, the gelatinous precipitate 
is permitted to settle ; tho supernatant liquor is 
decanted, the precipitate collected, rapidly stirred 
after the addition of a tittle cold waUr, and objected 
to pressure. In truth, however, this process is at- 
tended with some loss, for even cold water will ra. 
pidly diaaoWe the precipitated glaas in consequence 
of its minute division. The acids decompose ^e 
solution of glass. They also act upon it when solid, 
separating the ailica in the form of powder. 
( To be cuntintttd t 

Chinese Weiffkh.—Kn interesting experiment has 
recently been msde at the Royal Mint, in the pre- 
sence of its principal officfr*. A set of Chinese 
weighta was compared with the English sUndard, 
and the reeulta were found perfectly to correspond 
with similar comparisons made in China, nearly a 
rentury ago, by the miuiooary Duhalde, of scientific 
memory. 



80 



MAGAZINE OF SCIENCE, 



MEDICAL RECEIPTS. 

PoitOh Jot Bvgt. — Dmolvc I ouDce of biclilo- 
ride af mercarj (corrostve sublimate) id a pint uf 
rectiBed RpiiiU of wiue, antl odd 4 ounces each of 
caaUir oil and tarpentioe. 2d. receipt. — Reduce 
1 ounce of bichloride of roercurj, and 1 of white 
ancnic to a 6ne powder, mix %vith it 1 ounc? of «al 
ammoniac in powder, 2 ounccfi rAch of oil of CQr|)cn- 
dne and yellow n-ax, and 8 ounces of olire oil ; put 
all these in a pipkin placed in ft pan of boiling 
water ; and, «hen the wax ia melted, stir the whole 
tilt cold in a mortar. — Brandv'n Chemintry. 3rd. 
—A *oIntion of sulphate of copper. 

F/y Wfl/er. — Either of the above receipts mty 
t>e UKrd, but being poisonoiu, should not be placed 
where children hare^cci-u. l^Tuit is as good, and 
perft'i-tly hannless, exce])l to the Ales, Is the water 
in whieb quassia hai been boiled. It abould be 
fiomewbat nwcctcncd. 

littim qf Gilead. — f Solomon's.) An empirical 
me4lir.ioe, which it nothing but a disused prepara- 
tion of cincture of cardamoms. 

Balm vf Mrcca. — This ts rarely, if erer, to be 
produced genuine in Turkey, much less in Eoglnnd. 
It is a liquid resin, of a whiti.'th color, approaching 
to yellow, with a strong aromatic Sfuell resembling 
riiat of lemons, and a pungf-nt high>flavored taste. 
It is mut'h esteemed in the East as a cosmetic. — 
'U''hat in sold here for balm of Mecca, is some of 
the finer balsams scented with nil of lemons. 

Balvt of Rakatirt, fJordtm'M.J — Ad einpiriral 
nostniro, prepared by disguising common gin with 
oil of rosemary. 

Bctsam qf Jlonpy. fUUr».J — A nostrum pre- 
pared with n^ual weights af honey and balsam of 
Tola, and diluted with rectified spirit. \MUiout 
the spirit it would he a good expectorant. 

BaJnam of Honey. {Prrtorat.J — Tliis ia idmply 
the Alcuholic tincture of Benzoin, or Balsam of 
1'ohi, It cnnlains no honey. 

liaham ^f Harthmtnd. (Fard's.J — A nostrum, 
the uctivc (ngrediftit v( which is opium, being an 
infusion of Imrehonnd and liquorice-root with a 
large proportion of brandy and opium, with cam- 
phor, benzoin, squills, and hmey ; and flavored 
with oil uf anise. 

BaUmn qf Life. — This is merely the componad 
Je'"octioii of aloea. 

Balsam ^f Litjhorief. — A nostrum prepared with 
lic(Uorice, opium, and balsam of Tolu. 

ftftrriay'tf Antibilous Pills. — Take '£ drams of 
rxtrnct of <iolocynth, 1 dram of extract of jalap, 
1 \ dram of almond soap, 3 drama of guaiac, b 
gruius of potaiutio-tHrtrste of antimony, 4 drops 
each of the esselilial oil6 of juniper, caraway, and 
rosemary, make ioto a mau with syrup of buck- 
thorn, and divide into five dozen pills. 

Bateman^a Pectoral Drops, — A nostrum whose 
biitiis is tincture of castor. Take 2 ounces of castor, 
I utinne each of opium and oil of anise, 8 onncea of 
camphor, 2 ounces of sweet fennel-seeds, A ounces 
of tincture of antimony, and 1(1 pounds of proof 
spirit; color it with cochine&l- Other formulae arc 
given, varying in the proportions, and sometimes 
In the ingredients. 

Bates's Anodyne Balsam. — Thhs nostrum is the 
ooBipouml tincture of soap and opium, und is pre- 
pared with I ounce of tincture of opium, and 2 
ounces ol opudeldoc. 



RattUy'M Grfm Sstsna Pcneder.—h mI 
{nippoBcd to be Henna lesTrs hnttrd till thvyln 
yellow, and then miied with powdered efaaroOi 

Batttey's Liquor Opii Sedativ^ta, — A ferrr 
paration, which la s powerful nitft 
uniform and mild effect thin other , 
opium. It is chiefly eompoved <>r areu 
morphia, and may be imitated bymaoeratiai 
tartaric acid the drrgt lett aibr "■^i.""' »"■•-• 
opium. Mr. Uattley's prcpar 
well without the addition of sj t 

ita superiority as a mild narcotic. 

Bear*s Grtane. — There are two sorts nf 
one of the consistence of thick oli^ 
procured by boilinsr. from the fat - 
and the inteatines of the animal; tbt: ijlilcc, 
harder, and in appearance like frozen bone 
tained from about the kidneys. Both soiti] 
rank, rancid, and intolerable smelL Raadi 
is oden sold for bear's grease. 

Bittering, or corruptly Bitrem, a fraudoleii 
paration, sold to brewers and others for adn 
ingbeer. andcoroposedof coculuf in<1i ' 
tobacco, quaasia, and aulpliate uf ir' 
A similar prejtaratton is sold for the ruuui j.. 
under the name of bitter balls. 

Black Jyrop, or the Lancaster or Mnni 
hlaeh drop, or the Quaker's black drop. Tl 
lowing is the originol receipt, publi^^icd b 
Armstrong : take ^ pound of opium alioe^ 
3 pints of good Terjoice, 1 \ ounce of nittine| 
^ uuoce of oaflron. Boil to a proper thJo 
then add ^ pound and tiro spoonfuHa of ^ms 
the whole In a warm place ue"- '^■' »>•■'■ *'•* 
eight weeks, then iu the open 
syrup, when it is to decanted, 
up, with a little sugar added lo en> 
drop equals three of the Tincture ol 

Black Rtfiter. — Boil in 2 pint* ut 
to 1 , 2 uunceb each uf Aleppo galls, in 
of logwood, 1 ounce of gum itrabtC) 
sulphate of iron. Thb amy be cTaj 
powder. 

Black Wash.—Wnh together I 
water and 2 ounces of chloride of merm! 

Blaiue's Powder, far the ih^ 
disguised preparation of the si 

Bleaching Liqvid. — ^^^IM is ?'<!<j underl 
is solution of the chloride of lime, which 
kept in the market under the name of Blti 
Powder, Bleaching Salt, or Tcnnanl's Salt, 
a deliquescent salt, of a sharp, bitter taste, i 
in alcohol. It is a chloride of lime (not of cm. 
mixed with hydrate of lime. It is prepared 
posing thin layers of recently «laketi Lime I 
powder to an atmosphere of ehlonne. Chin 
potass, prepared in a similar way, is »Iao foU 
this name. The snlphuret of Itme b altfol 
the some way. but is not so eAcacit 

Boerhaave' s Astringent PoWUt 
prepared by mixing equal parta of' 
and Armenian bole. 

Brc^hfs Ball, is prepared by 
Bath brick, 2 pounds of pipe clay, 
pumice stone in powder, and 6 
and coloring the mixture to the si 
with uchre. umber, rose-pink, Stc. 

Bitter Principle of WeWer, is procured b] 
ing oilk with nitric «ctd. ll oonilsta of car 
acid. 




LoNiKiM .—Prutud by u. rftANOit. 6, Wblle Hune Lao*, Milt fioO.— rubUshnl by w, Uafnaiw. 11. Pat«ntasicrfl 




THE 



AZINE OF SCIENCE 



^nt Skctool of ^rt0. 



SATURDAY. JUfiE Ifi. IMI. 



[lU 




82 



MAGAZINE OF SCIENCE. 



DOMESTIC GAS APPARATUS. 

Tas Domestic Gat ApparAttm, «hown in the en. 
graving, is an Invention by Mr. Hinkiifl, for ttie 
tunnufacttire of gas on ku imall a imic aa to he 
adapted to pHvate houses. An apparatus of the 
h.U)d was exhibited in use for a confiderabic time in 
the Strund, and we believe the invention hiu been 
adopted in various estrnsive privnie establishments 
■nd ftiiia'l iii^uiufactorin. Ki^. 1 it a front cU-vii- 
tioit ; ti^. 2, a lateral section of the apparatus ; fi^. 
.t, n section uf the retort ; tig. 4, is a section of the 
rond/'OBer. In tigurea 1 and 2, the same letters 
refrr to the same parts. A shows its application to 
a kitchen mnKP, hut i* equally adapted to any other 
common fire-place ; B U, 6g. 2. U a recess or fur- 
nace built in brick at the bAi:k of the lire-place, 
covered in front by an iron yi\mit, and Us\in)^ a Que 
opening in the chimney ; E, fig. 2, and 1, 5^. 1, is 
a cylindrical retort, divtdrd hy two or more internal 
psrtitions, radiating from a conical pipe F, us 
shown in lig. 2. The retort is turned wiih a small 
rim or flange at the fore end. vrliich htfe into Ihe 
plate, and the hinder end is supported by a stout 
pin projc-cting from the bsck of the retort, and rest- 
ing in un iron aot:ket let into the brickwork. The 
hinder end of the pipe F terminates in a cup or 
csvity fi, pierced with several holcf, and serving as 
a chamber for the gan to collect irv ; the pipe F is 
also pierced with numerous «msll holes, tu allow 
t)ie tar, as it forms, to fall through them upon the 
burning fuel, where it, as wtll n* that portion which 
runs down the conical pipe F and the cup G, is de- 
rompoftcd snd converted into gKs. In the fore end 
of the pipH F is screwed a stuffing box. through 
which passes the pipe H, leading to the condenser. 
Each compartment of ttie retort has a door or 
mouth-piece MM. by wtiich the coal, or other 
msteniij for making gss, is introduoed, and the 
door IB seriirt-d by screws, the joints being cither 
ground trut- or luted ; N is an iron plate, eliding in 
grooves, and when lowered down, scrvittg to de- 
feud the face of the retort and the pipe H from the 
motion of tlir fire. Fig. 4 is a vessirl divided into 
two parts, the lower part O, which is air>tight, con- 
taining a quAUtiiy of tar, into which the pipe 11 
dtps a few inrhcs ; it is supplied with tar from 
another vessel V, by me^ns of a bent pipe Q ; R is 
■ pipe fur drawin;f utf the tsr uhvn required, atxl S 
an opening by which the tar ruiu down the pipe K 
into H, and Uierioe into the retort. The upper di- 
▼iiion of fig. 5 contains & range of bent pipes L L 
surrounded by water, one end of which, V, opens 
into (>, and the otlier end X leads to the gasometer; 
from tlkc lovrer bends of these pipes short pieces 
Y Y dcdcend into the tar in O, by which meaos 
the lur condensed im the pipes L L de.«cends into O, 
while the ga< rannot escape throogh the tthori pipes. 
The opffralion is as follows : — Tlie retort being 
charged, and the doors ttccorcd, the retort ia tamed 
tiU the chambers are in the position shown in figs. 
1 and 'Si the shutter N u then let down and the 
fire lighted, a portion of the heat nnd flame from 
which pasKes through an aperture in the bock of tlie 
range into the furnace B, causing, in a short tiine, 
the lower part of the rctart to brcome red hot, and 
the coiiU or other materialH in the interior to give 
out gas, which, colleciing in the chamber G, passes 
thritii^h the piprn P and 11 to thr condroscr ; at I 
Che same time the tur ^ivcn out by the couU in the 
uppi-r chmitlHTi of the retort, drsctinds thruugb F 
aud G on tu the buruuig lucl iu thu lower cUautM^, I 



and heeomrs ilcoomposed. When tt ta snpfiiMsiA 
that the mutcruls ill the lower r-.r-:-.-. 
given out all tiie gas cuntiinrd in 
is turned purlly round, so as to br; „ 
partment immediately ovpr the flame, wlim tlnr 
gas is again given out as before. The gas, tliai 
formed, contains tar and other imptuitira, froai 
some of which it can br freed hv a rrdoelion c4 
temperature; Che pipe li is, thoi --.'.» to 

dip a few inches into tlie tar veasr <ugk 

thin tar the gus hoa to rt»e to enter ...naef, 

by which means it is divested of a portion nf U* 

impurities, and upon entermg the r.-nd 

passes through a great length of ( 

by cold water, when all the condt i 

are aeparated, snd dntecnd Into the c.tr 

tlie pipes Y Y. The tar, aa we have before 

retnms to the retort by the pipes K and H, 

decomposed by fulling on the burning coke 

retort. From the condenacr the gia pn^'c* 

purlfter, and thence to the gas-holder; i' 

thod of purifying the gas, either upon r. 

small 8c»le, forms the subject of a srpjr.iic ^LuaL, 

to Mr. Pinkos, wbit^ we shall now prucevd ta (1^ 

scribe. 

The purifying substaDOea employed by 
Pinkus, are the chlorides of soda or of lime, 
engraving, No. 5, represents an arrangeount 
purifying vessel, adapted for the tue of 
houses, to purify the gas aa it pasaes frooi 
public main to the bomerB. The method j 
follows: — The ga», upon leaving the "■ ' 
passes through a solution of tljc chtori>i 
or of lime, which may be conlaiurd In 
sembling that shown in aectton at fig 
which the gu may be made to pass, n. : 
a pressure of from tea to twenty iiK'hc« "f » 
by which means it will be pnntie«l. and its 
noxious odour and bad sniL-II 
ture of thia tcsscJ t» easils 
foUowiug short dcscriptiuQ. i .^. .. .. ,.i,=>...j 
or iron cirruUr vevsei, ctosrd at both ends. 
andCC are two shrives which abpe_ down 
and pass round the vcs»cl. A is a pipe whick 
trnds very nearly to tike bottom. D D are 
circular shelves, put up and flxed to (he 
pipe A. £ is a pipe to fill Ihc ve^el with 
F the pipe to convey awoy the purified ^a*. 
H CLHika to empty the vea»el wbeti rr<]uisile 
preparing the solution, the patentee directs 
ploy one part of chloride tu about thirty-fi< 
of water, and when the chloride is in ib> 
ceutratcd slate a diluted acid, sulphuric ori 
may be added to thr solutiou toNA»i»t the 
of the chli>rine gas from the lime; and cbe 
of water may then be inurcused to /ortj 
parts, with one of the chloride. 



SOLUBLE GLASB 

f liftumt^/nfrnfMigt 70* atad 
Vk«4. — Tlie properties of - 
numerous and varied appii 
used io the theatre of Muni^i. ■,• 
from Are. All aorta of vrgetat 
cotton, bemp, linen, paper, Aci. . 
known .combustible ; but, in order that Uii 
bum, two conditions are re{|uUile, an ele 
perature, and free routact of air, to 
oxygen necessary for their transfonnalion i 
and carbonic acid. When otirv »^t an 
own combustion develojiea Ibe he«t oe 



fui 



flr«^1 



^^■fa 



MAGvVZJNE OF SCIKNCE. 



sa 



the cliemical action, provided their be in 
trilh u\r. \( dcjiriied uf sucU couUct, and 
hnii Ibc7 wUl, it it true, yield inflamnui- 
le products, but the carbon which is left 
barn, as it u deprived of air. and thui the 
>ii iiUl atop it»ir. Such is the part which 
ed fufeibli: ialts are capable of performing, 
. in Addition, cotD|>o5cd of aubi>tances iii- 
tit jricldiiig thfir oijrgeo at a low red heat, 
csrboo or hydrogen. These stUta melt an 
table matter bfcomes heated ; they futia 
■ coal impeDCtruble to the atr, and cither 
i^ltiigethcr, or limit its combnation. Tbo 
and borate of ammonii hare such a cha- 
they are so reatlily soluble in coid water, 
liable to objections which faiinoi be ur^ed 
lulde glass. AUhuugh Auluble glou is of 
pod preservative from lire, il fulliU the ob- 
r when it is mixed with another combus- 
' in puwder. In this esse tlie solution of 
in C^ same manner as the oil of piiuters. 
eoAto have more body, become more 
re durable ; and if the substance which 
be of proper i|unlity, coagulate by the ac- 
R into a strongly adhesite crust. Clay, 
calcined boue?, powdered glass, ^(C. may 
Bployed for tJiis purpoae i but we cannot 
rilh cirtuinty which of them is to be pre- 
pA nii\ti)rt* of cUy and whiting appears to 
than cither used separately. Calcined 
B, with soluble glass, a very solid and 
auku. l^ittiargr, which, with the glou, 
easily fusible mixture, does not give a 
t«d for coating wood, as the mixture con- 
trying ; it therefore cracks, and is easily 
ft Flint glass and crude soluble glaM are 
additions. The latter ought to be exposed 
r aflci It is pulverized, in order to attract 
if ic be mixed witli the solution, and be 
fiea to any body whatever, it. la a short 
a eoatiog as hard as stone, which, if 
bff of qo.xl quality, is unalterable by ex- 
knd re«iat£ fire admirably. The soorisc of 
lead, fct>p)r, floor, may all be employed 
iblt gU«* : but experience alone can decide 
thes« substances is the best, and in what 
B Ihoy are to be employed. We should 
It Uw ftni cuat should always be a simple 
if tbe glaaa; and that a similar solution be 
WW eoats composed of its mixture with 
i> irticularly when such a coat is 
Tbe last named Bubatancea 
•tiable coating, which safiers no 
to the air, diKS not involve nay 
is readily applied ; hot, in order 
not fail, particul.tr care is to be taken 
4riDg and employing it. In order to 
•lid t>(her bodies with it, the solution 
« of pure glass, for otherwise it would 
Hualiy fall ofT. However, a small 
ty is not injurious, although, after 
jght eOlorescencc Hill appear ; this 
will) water, and will not show 
time. When a durable covering is 
fen wood, tuu strung a solution rouftt 
ycd at fint ; for in this citae, it will 
will not displace the air from the 
ec)uenre, will not adhere itrotigly. 
to rub the bru»h several tintes 
ace. and not to spread the coating 
Pur the last coats a more concentrated 
J be employed ; atiU it muat not be too 



off 



pi- 



thittk, and must he ApreJid as evenly ns posaible.^ 
Esch coat must be Iborougbty dry before aoollier If 
applied; and this will take, in warm, dry weather, 
at least twenty-four hours, .\fter two hours the 
coat Appears to be dry, but is still Jn a itate to be 
softened by laying on another. The S!ime incon- 
venience Mill then nriiic, which occurt when a thick 
cont [if a concentrstt'd solution is ajiplied ; the coat 
will crack, and does nut adhere. This, however, 
is only tbe cuse when potassa is the base- of tlie 
gla^s, for that formed from soda does not appear 
to crack. In applying soluble glass to tbe wood- 
work of the theatre at Munich, 10 jwf cent, of 
yellow cluy (oc^trcf) was added. After six months, 
the coat had sulTered but little change ; it was 
damaged only in a few places where it had need of 
some repair. This aroK from a short time only 
baring been allowed for the preparation and appli- 
cation of the glass, and they were, therefore, dons 
without proper attention. When this mode is em* 
ployed for preserving a theatre from fire, it is not 
enough to rover the woodwork, it is also necessary 
to preserve the scenery, which is still more exposed 
to danger. None of the methods yet proposed for 
this purpose appears as sdvantngeous as soluble 
glass, for it does not act upon vegetable matter, 
and completely fills up the spaces between tbe 
thread ; it fixes itscif in the web in such a way that 
it cannot be separated, and locrea&es the durability 
of the fabric. The tirmncss which it gives to stutfs 
don not injure them for use as curtains, because 
It does not prevent them from bring easily rolled. 
So far as the pointing of scenes Is concerned, the 
glass forms a good ground for the colors. To pre- 
vent the changes which some colors, Prussian blue 
and lake for instance, might undergo from the alka- 
line mutter, it will be*^e4.-e£sary, before painting, to 
apply a cuat uf alum, and then one of whiting. — 
There is no great dilliculty in applying soluble 
glass to cloths ; still this n|)erstion is not so easy 
as might at first be imagiucd. It is not suffidcnC 
to cout or dip them in the solution ; they still re- 
quire, after this operation, to be subjected to pres- 
sure. This object might, perhaps, be best attained 
by pawing them between rollers plunged in the 
solution. W^hen a cloth is only coated with soluble 
glass, and put into the tire, it will rvmoin incan- 
descent after it is token out. This is not the case 
when it has been properly impregnated with tliis 
solution. A still better purpose is answered in this 
case, when litlurge has been added to the solution. 
The stuff in drying yields to the shrinking of the 
mixture, and bt-comes inseparable from it, nhich is 
the reverse of what happens when it U applied to 
wood. A single |>art of litharge in fine powder ia 
sulfiuicnt for fourtcoo parts of concentrated liquor. 
Soluble glass is capable uf many otlier applications, 
and partittuturly as a cement ; for this use it is 
superior Vi sll those which have hitherto been em- 
ployed for uniting broken glass, porcelain, &c. It 
may be used in place of glue or isingUtiS, in apply- 
ing colors, altliough, wheu employed by Itselif, it 
docs not moke a vamisb which will preserve Its 
transpareiwy wheu iu contact with air. 



CHANGES WHICH THE STOMACHS OF 

CRABS UNDERGO. 
A THKY accnrate account of these changes is given 
by Dr. K. £. V. Boer, in the lUth number of 
" Miiller's Archiv." Crabs, it is well knovm, 
change their shells at a certain seasoD of the year ; 



«• 



MAGAZns'E OF SCIEKCE. 



ftod U is a very oM opinion that the; chan^ their 
Biotnachs at the lame time, a new stomach being 
formed round tbe uld, which is digested hy the re- 
cently devcloijed organ. Baer haa proved that the 
crab's stofnnch consista of two coats ; one inner, 
which, ill every respect, may be compared to a cal- 
lutu. horny cpidrrmis, and which is destitute of 
vitality ; and an outer or containing coat, tronspa- 
rrnt, hut aufficicntly strong and vascular. The in- 
ner cuat coitsiftts uf varioaa and very curious parts, 
aoine ri'TiembHng bony plate«, others compared to 
Reth : now, at the period when the crab changtis 
tU skin, it likewise casts the inner coat of the 
stomach, and, on thja sceount, this process, analo- 
gous Co the moulting of birds, and to the renewing 
of hair in qnadrupeds, is, in the crab, attended with 
very great confitiiution«l distarbance, and a toul 
interruption of the digestive function. Bner relates 
rery accnratdy the changes which the stomach un- 
dergoes preparntory to the casting of ita inner coat. 
It would be beside our present purpose to follow 
him in this description, however interesting. Some 
tilings he mentions are, however, specially worthy 
of remurk ; in the first pitice the softer ports of the 
old epidermis or inner coat uf the stomach arc very 
nkpiJIy digested in the stomach, as soon as it has 
recovered its functions, and has, which it does 
quickly, fbrmed a new lining on its inner surface. 
But there are other harder parts that cannot be so 
readily digested and dissulveil, and which are other- 
wise disposed of. The hard and hollow bones, 
popularly termed the treth, arc got rid of by being 
discharged through the external oriflee correspond- 
lug to the mouth. There are other solid plates of 
the epidermic |>ortion of the stomach, which are 
not of a shape oidculutcd to^irritate the new and 
tendrr rpidcnnis, and, consequently, they con be 
retained nilh impunity, and ure destined to p<'rfurm 
a tu'w and curious function, fur, according to Dser, 
these plutcs, for some time preparatory to the oct 
of casting the shells, rapidly increase in weight and 
in solidity, so av, nt the period we arc speaking, 
they may he conridered as forming conaiderohle 
reservoirs of earthy matter, to be gradually dissolved 
and digLHtcd in the newly-lined stomach, nl the 
very time earthy matter is required by the animat 
for the formation uf it^i new shell. These plAtra arc 
popuhirly called eroi-alonen, and, when submitted 
to the digestive prorr«s, soon lose their maghness, 
■nd become smooth and polished befoie lhf>y are 
entirely dissolved. These crob-stnnes are chiefly 
composed of carbonate of lime, and Baer has proved, 
by repezited analyses, that the fluid contents of a 
crnb's HtumoL'li cont/iin, ot the time these .atones 
are in them, a considerable pornon of lime, carbonic 
acid, and muriatic acid, It is interesting to ob. 
serve, that the chemical inveatigatiuns of Dulk, 
render it highly probable that the chief solvent in 
the crnb's stomach is the same acid which plays so 
important apart in human digestion and in dyspep- 
sia, xxz.Jiet muriatic acid. 

BOTANICAL NOTICES. 

A 9TBM is that part of a plant which supports the 
Howers and leaves. It usually grows upwards, and 
towards the tight, hut occasionally it trails along 
tlie ground, producing young pUnts at intervals, as 
Jw the ruNner of the strawberry, and not unfrequently 
within the ground, as in tho couob grass, the mint, 



Sec, already described as roots* hy m 
such stems are generally known. 

Stems are most scientifically distin| 
their structure, whether belonging to die 
or monocotyletlonoos plants; thoae of 
class are called rxoffynous stems, incr< 
by a layer of fresh matter to their outer 
time to time, and being hardest towarda 
Those of monocotyledonous plants, 
yffJtov»i increaae by a deposit to their 
therefore force* the former part onti 
are hardest on the outside. These diad 
however, too difficult for the yonng bol 
following more usual and obvious 
therrforc continued : — 

lyuneut or 7VttJi*. — This is seen i 
shmbfl, and is the only kind of item 
most complete stnictnrc is plainly diM 
consists of bark, wood, and pith. V 
sacb a stem as this across, we find out 
very tliin sitn, called the eitfielf or 
When this is stripped off we find fixed 
^rwe back or corte-r. The next coal 
f^ark or iiber. All tbeae three diatitM 
called hy the genera! term, the bakk ; 
tended to preserre the inner portion froc 
of droaght and exposure to the weaibcn 
in Che inner bark that the principal aap 
contained, by which the moisture tha 
previously absorbed by the rmits ia carri 
Wit!an the bark is, first, the new wood 
— this is the lost portion uf the solid 
haa been formed, for tree* increase by a 
of wood being depoatted yearly and« 
llins, by conntiDg correctly the numl 
seen upon a transrerae section of a 
of the tree of which it formed a part 
tained. The alburnum, which is I 
workmen by the name of $mp, is more 
uitunlly of a lighter color than the ol 
This difference of color is ^crj often 
rulers which are made of lignum nl 
alburnum is white, and the rest of 
bUck. Under the albuntum ts (be rrof 
wood, or ligmvm, and within this, in 
the whole, is the pith or ruedntia, i por« 
body, occupying frequently the greater j 
shoots, as in the twigs of the elder treo^ 
grees becoming smnllcr, until in prooa 
is nearly or entirely lost. Joining Ihs 
burk, and running through the whole 
the wood from tha centre outwards, are 
or flakes — these are tlie medvilMty 
stitute what is called the Mttfr 
plninly in the oak when cut into boarda 
and adds much to the beautifully mot 
ancr of mahogany, satin vpood, ^. 
always divided more or less— in 
ground, in trees not till some oonaic 
above it — the larger and thicker divisioi 
hranche$ or Oftvtjhx. and the smallrr 
thoolSf or Mprayi. The whole of whic 
getber ia cadled the head of a tree. I| 
off, the tree ia suid to be a pollard, •»« 
a pollard willow, &c. If the side bnwi 
separated it is said to be lopppd. 

CauliM or ntem, — This inolade* tl 
most herbs, and is an imperfect state oi 
kind ; for on account of its shorter di 
bacooua stems lasting hut one year,) an 
greater rapidity of its growth, there ia : 
between new and old wood — the onl] 



MAGAZINE OF SCIENCE. 



85 



y, ftnd the pith Is either very much In 
or »lta^ther wanting; io whjcb latter cue 
bfcomei hollow. 

if fl nimr given to the stem of the 
!e» tbe COCOA nut, and other spedrs of tbe 
it inrtreftsn in length jear hj year, but not 
Aer: it is knotted on the nurracc bjr the 
oU leives ; and \b not formed of layers of 
t of an irrr-gular fibroua maif. the outside 
is exceedingly bard. The stipe is scTer 
It and bean leaves only at the top. 

or ttratr, ia a hollow jointed stem, 
ily in the tribe of gntssea. Although these 
deed no hard woody substance to support 
ibey are not feeble — for the materials of 
Rnr are formed, being disposed in a ring. 
ben stem twice the thickness it would be if 
hides which they are further strengtbeued 
' of flint upon their sorfaco, bj their solid 
d aheaibing lesves. 

ia a stalk which supports the flower 
B tbe primrose or cowslip : if Che flower 
I not come from the root, it is not a scape 
Hiafi/e, so if it supports a leaf only, it is 
stalk or yetiole. 

last-described stems admit of little 
but the trunk and cauUs are almost end- 
tr diflerenees of form, manner of growth, 
xonsistence, a stem msy be either woody, 
succulent, pithy, solid, or hollow. In 
md, Ttrioualy angled, winged, channelled, 
vm^, &c. He. In manner of growth, op- 
red, procambmt, or lying on the gronnd, 
or twining around the bodies. It maybe 
H twi»teil, amootb, or covered with hairs, 
thorns, Ac, while its Tarioas branches 
rom it in difTcrent directions, and more or 
erouitly, according to the speciea of the 
HadtfAh they funn so considerable a part. 
^^■ftms are thin as hairs-— at others, strong 
^Pinilte the most majestic columns. In 
Sne iT|;ionSf almost absent, or reaching 
nn inch in height ; hut in the tropical 
, growing often to the altitude of two 
fe«t, wbile othf r stems, still longer, twine 
kem. These, clinging to each other, form 
from tree to tree, nnd again extending 
lis from the sommits tilt they reach the 
make the whole forest appear Uke a fleet at 
bat decorated from mast to msst with the 
Inves and splendid flowers. 
en already observed, as the first stem of 
cd from a bud, which is situated at 
embryo, called tbe plumule ; so also 
branch added to it by Its after- 
. arifcs, in most invtancrs, from a similar 
hud. If we eiamine tbe oak, ash, willow, 
ber tree, in the summer time, we shall And 
MBS or ajciU of all the leaves small ^caly 
I. ^Slien the leaves fall olT in the autumn 
be still more apparent : in spniig they 
w off* their scales, and burst into leaves, 
tirir snmmer's growth, tbe leaves, which 
fa a buuch, become removed from each 
nn e^xteusion of their axis of growth: that 
e formntion of a twig or stem between 
hUe in the bosom of every leaf is seen a 
ar to thst of the preceding season, and 
lioe time will grow In the same manner. 
t therefore, appear tlitt no fresh brauches 
uniesM buds be first formed ; yet in the 
ijrtlw, tad shmbe, bo buds are to be seen, 



and in tbe plane tree, though eridont enough in the 
winter season, yet in summer the buds are com- 
pletely buried in the stalk of the leaf itself. The 
axils uf the Iritves, and termination of the last year's 
shoots, arc the only parts in which buds are naturally 
formed ; but it sometimes bspi>ens, that buda 
appear in other purta of the tree; as for example, 
if a tree be lopped, buds will appear upon tbe old 
stem, and produce new and vigorous branches — all 
such as these are called adrentitious buds. Goose- 
berry trees, too, often spontaneously throw up 
xuckert ( these arise from such accident^} bods 
being formed below tbe ground. 

Buds, as above described, are to be considered as 
arising from the wood itself, and not from the bark 
or its vessels : thus, the branch or twig which it 
produces is firmly connected with the last year's 
wood, and the bud in general only grows so long as 
the connection between it and its parent twig is 
kept op ; but this is not the case with all, for in 
certain plants imoU buds or bulbs.called by botaniata 
petHntOf, are found in the axils of the leaves or on 
the stems, which are readily separated, and if im- 
mediately put in a situation favorable to growth 
their vitality continues, so that they maintain a dis* 
tinct and separate existence. 

Well-known instances are the bulbous toothwort 
and the tiger lily, along the atcni of which very 
many gemmae are borne. Another example of 
gemmee is seen in the tree onion, where, instead of 
a head of flowers, and afterwards seed, is a number 
uf small bulbs of a simitar character. An exami- 
nation of the bulb spoken of nnder tbe description 
of roots, show that these, Uke buds, consist of a 
number of scales or coats folding over each otlier, 
and shielding from injury the growing point in the 
centre, and which alone produites tbe future stem, 
flower, and leaves — the scales themselves decaying 
away when no longer wanted. It will be observed, 
that the solid bulb of the crocus ia not of tliis for- 
mation — the growing point is at the top uf it, and 
not withtDsidc. It, however, wastes away year by 
year as they do, a new bulb being formed below it. 
As was before stated, this is colled a cortHtu or 
swelled -out under.gronnd «tem. 

In some uf the species of a particular tribe of 
plants, (the orchis tribe,) the stem forms a bulb 
above the ground, also solid ; this Is called a 
pxeudO'bulb, J 



SMALL AIR BALLOONS. 

Fon experiments in courses of natural philosophy, 
mechanics, and chemistry ; as alao for determining 
the currents existing in tbe upper regions of the 
air, there are required little ballooas of hydrogen 
gas, whose small weight and ascensiooul power may 
enable them to rise to a sufficient height. The 
baudruche or blind gut of tbe ox, prepared for tlie 
use of the gold heater, is the best aubstance that 
has hitherto been used for this purpose. 

For the purpose of making the ^mall air billoonr, 
a mould is necessary, made either of wood, or 
which is at once cheaper and better, of plaster of 
Paris. This mould is generally a hemiapheri! of 
2-1, 30, or 36 inches in diameter, and is pUced upon 
a stand or table, so tbst a peraon may walk round 
I it. When used, it is to be carefully greased alt over. 

The baudruche, or prepared akin, when bought 
of tbe bladder-dealers, is in the form of very dry 
and very hard slips, la order to cover the moold, 
(he skin ia soaked io warm water for 12 or 15 faoan; 



86 



MAGAZINE OF SCI 



it u iheo tprrad ont witb grnt care. 0Bd spplird to 
the mould, beginning At the top. The rmg^ca ed^es, 
or any accidental inctjualitiei, are to be remored 
with a deal of caation hy m pair of cntting pin- 
cen. A second baodrache is then applied* so ai 
to cover ooe-half o( that applird to tlic mould ; 
and then ■ third, alao eoTeriag ooe-half of the 
■ecood. and to on, in snch manner that every part 
oi the moald may be coTcrtd with two thickneaMA 
of skio. Care maat alao be taken that the ikio 
already on the inoutd be kept moiat until the neit 
layer is ajtplied, as otherwise the baodnichra would 
not adhere together; for this reason, a wet clulh 
mutt be kept on the skins until the whole Is finished. 

IK'hen the whole of the hemispbericaJ mould is 
finished, a tape, well greased, is tied round the base 
of the hcini^her* ; and those pieces of skin which 
Are left at the lower edge are rolled ap and kept 
moist, while the hemispherical part U left to dry 
for A few hours: when dry, the part already made 
is greased, to precrat the adhesion of the skin, and 
is used Ai a mould, beginning at the bottom with 
UiA loose fi-ipa remaining from the farmer hemia- 
pbere, and adding frcih «kios up to the top of the 
Mmlsphere, where a short cylinder, aboat an inch 
in diameter, ts placed, and the skins brought round 
It. To etrengtbeii this intended ojwolng into the 
balloon, the skin is berc trebled, or even fourfold. 

A few hours ire sufficient to dry this second 
homispbcrr, when it is to be taken off the mould, 
from which it parts with eaae, in consequence of 
the grease ; and in like mnnnrr the ts^ie is nitb- 
clrswn from the iutcmal part. I'be nozzle of a pair 
of hand bellows being then applied to the cylindri- 
cal mouth, it is blown np, and hcing tied, a very 
thin cost of varnish is rubbed over the surface by 
niAAas of a sponge. This being done, the balloon 
la tumod ioiide out, and a^ain blown up and 
vtraUhed ; after which it will hold hydrogen gas 
perfectly well. 

A balloon of this kind, 3 feet in diameter, when 
weJI made, ought not to wnj;h more than 2 ounces 
■nd A half: so that, when filled with pure hydrogen 
gas, it ought to rise in the Air, willk the torce of 
between 6 and 7 ounces. 



PYROLIGNEOLS ACID. OR WOOD 
VINEGAR. 

Ira piece of green wood be introduced into an iron 
retort or other close vessel, the retort bedded in a 
common coal fire, and a receiver applied, it will be 
found that in proportion as the wood heats, the 
water which constitutes its natural juices will distil 
over, and drop into the receiver. This water almost 
imtDediatcly changes its niture, and becomes first 
uerb, and then sour to the taste : it conies over 
impregnnted with a dork oil, whtrh soon puts on 
the appeardnct: of thin tar, nnd in fact, is such ; part 
of the tar tloatt, part dituolves in the liquor ; but 
the greater part sinks to the bottom of the liquor, 
jhleanwhilc gna, consisting of carbonic oxide, car- 
bonic acid, carburetted hydrogen, and bicarburrttvd 
hydrogen, is generated abundmiily. At length the 
liquor which conies over is very acid ; but its acidity 
^ in some measure disguised by the strong taste of 
the tar, which is dissolved in the liquor, and gives 
^ K reddish color. 

|C is easy to trace the theory of these changes. 
4lw wood chiefly consists of oxygen, hydrogen, and 
proportions, and in a certain 
The elements separate during 



the heating of the wood, and tliry rcconil 
diately after in dtfTerent proportionn, and^ _ 
to new substances. Psrt of the OJiygen and ' 
gen combine and form water. Another part 
nxyiren and hydrogen combine each nithaiKii 
carbon, and fonn two fif.ta of compuutuls, a 
oxide and carbonic acid, with carburrtted and 
boretted hydrogen. .Another portion of the 
and oxygen, with a very small quantity of hyt 
then combine, and produce acetic acid. 1 
maindrr of the carbon and hydrogen, with 
amall portion of oxygen, also unite and prod 
peculiar tar. The water, acetic add, and the 
distil over together, &n the form of what is o 
ooturnvTCK pffroHfuous acid. The acid whiol 
over towards the end of the distillation is tbri 
est portion ; no doubt because the water « bi 
timber contained has been at this time all voUtJ 

The name gi%eo to this liquor by the Frew 
mists was pyroHgneoua acid ; but it was ann 
by Foarcroy and Vauqoelin that it is not « 
wui femeru, or of a ]>ecuUur nature, as bad fa 
yean before been supposed. They deten 
be merely acetic acid disguised by tar. 
was by no meana a new discovery. Gl 
ascertained the same thing two centuriea 
in describing the carbouization of wood, 
this acid liquor, and calls it vinegar. The 
not to have been generally known ; for 
stated something similar to the French A 
1701 ; and Boyle details some experim^ 
spirit drawn from box-wood, in which 
detected an acid which '* was in iceiit 
vinegar, so that had I not known how 
tained I should have suspected it to 
radicatvm." 

Vinegar, whether obtained by ftrm*'"' 
the di:}tiUslion of wood, ia s dilute a. 
is, a mixture of a very coacenlmted. j 
inflttmmahle acid called the acetic, 
in variable proportion. The water muf] 
rated by a variety of means. Thus, if comi 
gar be strongly frozen, and the vessel in^'cr 
unfroien portion, in smalt quantity, vriUj 
which is acetic acid deprived of much wat 
be mixed with cbarcuul powder and 
liquor will come over (the first portions oT 
should be rejected), which at a moderate dej 
cold wilt shoot into beautiful crystals. Th< 
occtic acid, otherwise called radical rintfior. 

Acetic acid, wlirn as free froui Mater mm it 
made, is a colorlcM liquid at ordinary teiapei 
but crystallisrs in the cold: it has xn ci.-i-i 
pungent smell, and a powerfully acid 
ing (o actual caustiutty, When apyli ■ 
it is capable of forming a blister, and e\cii a t 
some eschar: it also destroys warta and otl 
crescencrfl. When heated so as to emit lap 
vapor will readily catch flame from any I 
body. The liquid sold under the name of a\ 
vituffttr is acetic acid, holding camphor ant 
essenlinJ oils dissolved. This compound w 
merly known under the name of riufgar <ffi 
ihifvei, or thievct* rineffar, on account of tlui 
ing circumstance: — "When the pljigua n 
Marscillefl, four rogues broke into the houod 
sick, and carried ofTwhatevirr they pteaaed, 
to a sernet place with their bfM>ty ; nnd ( 
turned to the same business at different tic 
they auisMed great nches : but tbri 
apprchtuded and hnuged. Being 
durst venture into the pcstilcalial fa( 



muo 

in\-cr 
riUji 

4 




MAGAZIXE OF SCIENCE. 



87 



Moautl 



tfurt tbMj pretervtfd tbemfielves by driokin^ s Ii;lai8 
of their vinr^r t*io or tlire^ tiaiei m day, fpriukUng 
their hAndkctchiefii and clothrs with the same, and 
Ihcj were not Nfniid.** The viiipf^r thua jierfumed 
■■d lurd by the tUieves wan, of rour«r, rommnn 
i lmA T , not acetic acid ; and all thai they contributed 
to tne invention was the idea of combining the 
AiiBcs of riueipir with the perfume of nromatica, 
ftzid using the compound as an ftlexipharmic, the 
powers of which arc Tcry questionable. 

Id pyrolijDcoiu acid manufactories it is usunl to 

prrparr what arc railed r^rf Uqvor uiid iron liquor 

for the use of calicopriatprs. The formRr is an 

fceeUite of alumioa formed by mixing; the aceUte of 

Gmr. herrnfTer to be described, with common alum. 

By <-i?mpoHition. icetatc of alumina is 

for' remains in solution ; and sulphate 

ol iiuir. Kiiu-h, bein^ insoluble, sobeidea to tlie 

bottom. I'his sulphnte of Hme is not allowed 

to r''< to waste: it ii employed BS the lute with 

■ end piecea of the retorts are cemented 

- it answers the purpose extremely well. 

Tba Uun liquor'iB made by dissolving old iron hoops, 

he. in tbe pyroligneous acid which has been recti- 

fted by di^nlUtion, but no further purified. In 

pyroliiineouti arid manufsctoriea llie at^id dues 

-> Oironch all tbe processes for puriHcation that 

^rrsently deecribed. After being distilled 

' iron retorts, the acid is rectified by a 

disttlUtion through a common still and 

br tticke means a purer acid is procured ; 

'-far from being as pure as ft is possible to 

The steps by which it may bo rendered 

»»...nv |*erfectly pure are next to be described. 

TIh appnratos and process employed for difitilliug 

PTroTicDeooii acid are ai follow : — The wood made 

: difttillstioD is introduced into a cast-iron 

i.aped like along drum, but of a very large 

i ilia vessel consi«ta of n cylindrical body, 

feet and a half long, and four feet in dia. 

Dinrr. imvini^ two circnlnr end-piects, which Ht la at 

ndi end of the cylinder, and arc secured there both 

M mi^^MpAble bolts and luting. The cylinder is loid 

-Jly in a fire-plare, the fire surrounding it 

■«-hnIe length. The eude of the cylinder 

■ beyond the fire-place, bo that they, 

■ two circular end-pieces, are always 
!>cn cool. From the centre of ttie end-piece 

linder springs a very wide tube intended to 

i ibe ignited wood, D3me1y, tbe vapors of tbe 

I , tlu- tar, the water, fee. This tube at length 

a large cistern of water kept constantly 

; ends in a copper worm surrounded by a 

' (try : the water, acetic add, and tar, are con- 

: it; they are discharged in a state of mii- 

« large ritttrm : here the liquor is allowed 

lie: the great balk of Oie tar subsides to 

Mfil. Above this lies the acetic arid and 

<ixed« and holding in solution as much tar 

iparta a considerable deftrre of taste and smell. 

tng r%n fhr aurface of all lies a little more tar 

> nee and trjts specific gravity than that 

It to the bottom. In order to nepa- 

iiqQor, which constitutes the middle 

up ii made use of. the lower end of 

_ ' *D fsr down into the acid liquor as to 

t a tew inches from the lower deposit of tar. 

Use pump i« pnt in action it draws the acid 

otit. and nt length tbe upper tarry surface is 

untU it joins tbe lower drpoiit uf tar, 

puiuping IS discontinued. Tbia is the first 

towM^s removing the t«r ; and by it the chief 



quantity ia removed. The add liquor removed by the 
pump is received into tbe body of a largo still, where 
It undergoea the procesn of diintilUtion. This distil- 
lation IS conducted slowly: the object of it i» tii re- 
move anothrr portion of the tar nhich is held in so- 
lutioti hy the liquid; and if the distillation were urged 
by A strong lieal, the separntion would be much lesa 
effectual. The first product that ditcila over is uf a pe- 
culiar nature : il is culled wowltjiirit, and is kept sepa- 
rated, for a purpose that will be presently mentioned. 
The product which follown this is still a tarry vine- 
gar ; for it now holds in solution not tar but the es- 
sential oil of tar : it has still the strong taste, but by 
no means so strong as when first obtained from 
the wood. When nearly the whole of the acid haa 
been drawn off the process is stopped ; and the tar 
now collrrted in the bottom of the stttl is allowed 
to run off by a oock. 

(Toht oomtinued-J 

SPIRIT FROM THE M.VNGO. 
Tea discovery that a very wholesome spirit, some- 
thing stutilar to gin, could be manufactured from 
the mango, was made some two year* ago in Gre- 
nnda,— and there was some talk at the time in 
Jamaica about establishing a distillery there. Tbe 
mode of proceeding is very simple : — A Tat is as 
nesrty filled as poAsible nith tbe ripe fmlt, and as 
much water added as will cover them. They are 
then allowed to remain from thirty-sU to forty, 
eight houra, until frrmentation commences, when 
the seeds are divested of whatever palp may still 
adhere to them, and care Is taken to retain the 
whole of the rind and pulp in the rat. Thirty-tive 
per cent, of water Is next added, and five per cent, 
of sugar or molasses. Tbe whole is then allowed 
to ferment for five or six days, when it ia transferred 
to tbe still, and ibe process conducted in the usual 
manner. The spirit thus extracted is mild, and haa 
nothing of the pungency of new rum. It is de- 
scribed as strongly resembling In taste Britiith gin : 
and this flavor ia derived, without doubt, from the 
essential oil, contained in the rind of the fruit. It 
is free from empyrcuma, and is pleasant and slightly 
saccharine. In Grenada, fifty gsllons proof 
were obtainctl from " a very inconsiderable quan- 
tity" of the fruit ; but it ia to be regretted, ** the 
quantity" had not been specified. Considering the 
deficiency in the staples of mm and sugor from the 
West Indies, for the last two or three years, this 
discovery may be considered of great importance 
in a financial point of view, since, should it become 
an article uf export, it may in some measure com- 
pensate for the falling off of the revenue. It rests, 
however, with the West Indisnsi whether or not to 
avail themselves of this very valuable discorery.^ 
The capital required for a mango distillery would 
be very vniall, while it appears to us, that if the 
spirit were used in Tamisbes alone It would bo a 
very profitable speculation. — Belhe GBxeit*. 

MEMORANDA. 
THrpin on the caute qf the Color qf Affates. — 
The red color of Agnte is owing to a number, 
greater or amalter. of Protococaa KentuirinM (one 
of the lower .AlgK), sccumutated together, or more 
frequently reduced to their small red globules, 
(seminulcs) agglomerated or coaguUted, and dis- 
tributed, according to certain circumstances, in the 
colorlesa structure uf these silicious compounds. — 
By microscopic and comparative inveatigatioa. Tur- 



: 



■ 



88 



MAGAZINE OF SCIENCE. 



piQ was led to conclude thftt the vMrioas colore, 
oninfe. roM, blood-red, nnd reddish-brown fvirie- 
tici Offing to more advanced grovrth) which are in- 
e1o«cd in, or which lurroand the tranalurid and 
colorless strticlure ofdifTerent kinds of AgsCes, will 
be found to be owing to the presence cither of red 
globules, Qiiironnlj mixed u in the Camelian 
Agate, or agglomerutrd into small irregular clots, 
■od diftributed into clrcuUr waves, according to 
certAia forms or conditions which existed st the 
time of the tilicious coDglomeration ; or finally. 
thougli more rarely, tn these small, red vrgctsbtes 
tbeniselTcs, f|Qite entire, snd most diatinrtly Tisible 
with the microscope. It is impossible to fiud a re- 
semblsuce In color and polish more striking thsn 
that which is seen in a wliitf" glsss phial filled with 
Protoeoccuw Kermfimif, when compsred with s cnr- 
netian, u may he fully established by the trial. — 
TUrpiH in Jameson'* Jonmai. 

TMMperiny on Slfft. — In the year 1739, Mr. 
Hartley obtatoed a pstetiC for a mode of temper- 
ing cutting instruments of steel, by immersion in 
oil, heated to a regolatcd temperature, meaAured by 
a thermometer. This v.-aa certjiinly a grcjit im- 
proTement, both in point of prerisJnn and di<tpatrh, 
on the common method of heating the instnirocnt 
over a dnnie, till a certain color, produi*ed by a film 
of Clyde, appears on its snrfncc. • These colors arc, 

At 430° F. a *ery faint yellow for lancets. 

14bU . . a pale straw color for razors and sur- 
geons' inBtmmtntfi. 
470 .. a foil yellow for penknives. 
490 . . a brown for scissors and chisels for 
catting cold iron. 
510 .. « brown with purple spots for axea 
and plane irons. 
530 . . a purple for table Icntves snd large 
ehcars. 
550 . . a bright blue for swords, watch springs, 
truss EpringN. and bell springs. 
560 t. a full blue for small, fine aaws.dag- 
gers, Stc. 
000 . . a dark blue, rerging on black, if the 
softest of all the gradations, when 
^ the metal becomes fit only for pit 

' and band sawp, wUirb rau»^t be sof^, 

' that their teeth may hear sharpen- 

ing by the file, and setting by the 
hammer or pliers. 
On /A« Infiufnct of a Low Temperature on the 
Jt\/kuoria. — The researches of Elirenherg agree 
with those of SpalUnzani. and proTp that cold is 
generally l^tsl to Infusoria, especially to the Rofa- 
loria. It ia even more destructive to the living 
animals than to the eggs ; but water, when recently 
thawed, may be found inhabited by individuals 
which have escaped death, and inclose the germs 
of future generntions. Hie animals generally die 
after they have been encased in the ice from one 
hour and a quarter to two hours ; but it appears 
thst at the moment when congelation of the water 
takes place, each animalcule is surrounded by heat. 
A sudden thaw always produces a fatnt effect on the 
Inftuoris. Tfasy are found in winter at the lower 
surface of ice, oovoring ponds, &c,— J/irrosco|nc 
Jtmtrmal, 

Mr. Owen calcolmtea that 200 ]>ersons, with 
machines, now manufacture as mui-h cotton as 
20,000,000 of DWD were able to manufacture with- 
out machinei forty years ago, and tliat the cotton 



now manufactured in the course of one ) 
Great Bntain would require, without nia« 
I I5,000,OOU of workmen with simple whock 
calculates farther, that the quantity of au 
turea of all sorts, at present produced by 
workmen, with the aid of machines, la to 
that it would require, without the asatstnnce 
chinery, the labor of -100 millions of workmc 

Vibration qf Wiret in the Air. — A gentle- 
Burkil, near Basle, in Switxerland. is said I 
observed, some years since, that a long wire sti 
in the air gave musical tones tn certain stotei 
weather. In consequence of this tad. other 
vations, a kind of musical barometer ia deseri 
having been ron.<^tructrd by Captain Hani, of 
in 1787. Thirteen pieces of iron wire, esc 
feet long, were eitended from bis $nranicr-hi 
the outer court, crossing a garden ; they were 
about 2 inches apart ; the largest were two I 
dia.meter, tlie smallest only one. and the othei 
one and a half. They were on the side of the 
and made an angle of 20 or 30" with the hi 
They were stretched and preserved tight by 
for the purpose. During ccitain changes 
wentJier, these wires make a considerable ooi 
scmhling that of a simmering tea-orti. ai 
monicon, a distant brll, or an organ. It an 
be snpposod that wires placed east and wei 
no sound, snd that to produce the rfffct thei 
be in the direction of the meridian. In the o 
of M. Diiberiener, as stated in the BnllctiaTi 
Ingiqnc, this is an clrctro-magnetical|ibenameT 
JVnr Monthly Magazine* 

yatuml Ice Caret, — In a memoir on aorat n 
ice-caves, read by Professor Pictet to the tli 
Society, in 1822, thst author advanced the sii 
fact which was attested by the nei^hbourii^ 
bitants, that Ice is formed therein more in M 
than in winter, and he accounted for diiseSee 
two roticoraitant causes, vis. : descending m 
of air, snd the cold produced by cvaporatioB. 
of the ice caves visited by Professor Pictet. is si' 
near the summit of Mont Vergy, in Faucignj 
is called Montarquis. To determine the fact 
absence of ice during the winter. tv«o counli 
of the village of Sionsler, near the road to tl 
cave, hud the perseverance and courage to 
three visits to the place during the autVRM 
winter, and having drawn up the foUowiog 
acoount of their visits, it was read before the 8 
of Geneva : — 

" On the 22nd of October we ascended 
ice cave of Montarquis with some difficulty, bi 
of the first snow, and we found very little 
colamni ; it had begun to meit. 

" On the 26th of November we re-ttsccDdsd 
cave ; we found very little ice at the boUooi ( 
cave, out of which there proceeded ft ki 
warmth. 

" On the 2rith of December we re-aseendcO 
above-mentioned ice cave witli great diificull 
trouble, and were almost carried away by an wall 
This circumstance discouraged us. but rceo 
from our fear we ascended to the spot. We 
a moderate warmth in the cave and no ice ; li 
of which where there was ire in snmmer. dim 
octually water : in winter therefore it is m\ 
this cavern, and in summer it is cold, T% 
appears cavemoua; it appears as if tbeft 
chimoies.** 



LmiWMr^l>rlnlvd bjr 0. rsAvoii, «. Wblis Horta Lsae. MUa Ead.— PablUhvd toy W. OairMw. tl, Pai#Tw>«tM t(- 




THE 



GAZINE OF SCIENCE 



^n& ^cDooI of Itrts. 



SATITRDAY, JDNE It. 1641. 



IHd. 



iiiiuiiiiitiiiiituiiitiiiiiiiitnuyiiw 



SAXTOK'S MAGNETO-ELECTRIC APPARATUS. 







THE WATER RAM. OR BEILIEU HYDRAUUQUE. 



'JO 



MAGAZINE OF SCIENCE, 



SAXTON'S MAGNETO-ELECTRIC 
APPARATUS. 

Ohb of the most elrfcunl. (H>nvcnient, ahd powerful 
magneto-electrical machines, it that o( Mr. Saston, 
the pritici)jle and node of actian of which hai been 
aJready deschtxd. tn tmling of an aiulogoua ma- 
chiDi), invented by Mr. Clarke; thia, hoMrc^er, baa 
tlie adrantoge that the amatore worka on the pnds 
of (he poles of the magtiet, instead of at the side of 
Iheni, by which meana the arrangeoient ia much 
aimptth«il. The machine will be immediately nn- 
df rstood by the foUuwing short deicriptioa, aud the 
figure to which it refer*. 

The magnet in this apparatai is 7 inches long. — 
The space between the potea. from centre to centre, 
2 incbea. A, a steel horse-shoe njojjnet, cnnaisting 
of three plates screwed together. B, the tirniatufe, 
or keeper, of soft iron. C C C, insalated heUcea 
of copper wire. D, a wooden cup for containing 
mercury* moyeable by its stem H. E, a copi>er disc 
dipping into mercury, and communicating, by a 
bruBs socket. I, with one pole of the helices. £', 
a pointed slip, or croas-bar, of cupper, in contact, 
by a central screw, J, with the other pole of the 
helices, and so adjusted, that when the armature is 
at right aiiglas with the polea of the magnet, the 
ascending point of the cross-bar shall be about 
]-20th of an inch above the iorfaceof the mercury. 
F, a grooved wheel filed upon the oxis of the arma- 
ture, B, to which mpiil motion is imparted by the 
larger grooved wheel and leathern band F. Q, a 
thuntb-acrew for adjusting the axis of the wheel, F, 
,•0 as to tighten or tUckea cbo btnd. 

THE WATER RAM. OR BEIUER 
HYDRAULIQUE, 

Aa it was called by its inventor, M. Montgolfier, of 
Paris, is a highly useful and simple machine, for 
tfafs. purpose of raising wotcr without the expenditure 
of any other force than that which ia produced by 
tbe momentum or moving force of a part of the 
water that is to be raised. The eiTect of this machine 
depends entirely upon momentum, or the new 
quantity of force that is generated whenever a body 
is put into motion ; '»nd the effect of this is »o 
great as to give the apparatus the Appearance of 
acting in defiance of the established laws of hydros- 
tatic equilibrium ; fur a muTtng column of Email 
height is made lo overcome and move another 
coUunn mach higher than itself. The form and 
construction of the hydraulic ram is »howii in the 
figure on the next page. Suppose O to rrprrsFnt 
a. reoervoir. or the source of o spring, which is con- 
tinnolly overflowing and running to waste by means 
of a channel a few feet lower than itself, oj at the 
level line P P, (we have shown a cask, the principle 
is the same, and the description as easily understood.) 
IitalBad of permitting the water to flow over the 
fidea of O, let it be conducted to the level of P P. 
by meana of pipes Q Q, connected with the side of 
the reservoir, and terminnting by an orifice R, in 
which a conical or other valve S is placed, so as to 
be capable of effectually closing the pipe when such 
valve is drawn upwards. T is an adjustable weight 
fixed on the S)iinillc of the valve S, by means of 
which the valve is kept down and open : any water, 
therefore, that is in tho cistern O will flow down 
tbe pipe Q Q, and escape at the orifice R. so long 
as the valve remains down ; bat the instant it is 
xjused and shot, all motion of tiie water is sua- I 



pended. Thus situated, tbe adjustme-nt 
T must take place, and by adding to, oi 
from it, It must he made just so bei 
capable of sinking or forcing its wa 
against the upward pressure of the wa 
of which will depend upon the 
distance from the surface of the wate 
point of discharge at R, (represented 
line O V;) conirqueDtly, if the valve S 
the hand or otherwise, all motion of 
the pipe Q Q will ceoae, but the ins 
is released, it will fall down and permit 
escape. The water, by its motion, 
mentum and new force, and cooaeq 
longer equal to the column () V, to whi 
has been adjusted, but ia aaperior to 
it is enabled to overpower the reais' 
weight T, and it carries the v«lri 
closes the orifice R. This is no 
the water ia constrained to become 
by which the momentum is lost, and t] 
weight sgsln become superior, and fi 
opening the orifice, and permitting t 
flow again ; and as the presaure of tbi 
the weight of tbe valve esdi alternately pr 
the valve is kept in a constant state 
or of opening and shutting, without ■ 
aid whatever. Such ia the principle I 
the motion of the water in the pipe 
daced; but the motion generated cannot! 
annihilnte«l ; and it is not only of su 
to raise the valve S, but likewise to but 
lower end of the pipe Q Q, unless a 
be provided, by which this arcumolai 
tscape. Accordingly a second valve 
near the lower end uf these pipes, and 
open upwards into an air vessel W. 
charging pipe X, and consctjuently, i 
valve S is closed, tbe water which wou 
have flowed from the orifice R now o 
U and eaters the air vessel, antil the 
coutoined oir overcomes the gradually 
force of the momeutam, when the valv 
and that at S opens to permit the w 
set-find blow or pulsation, and in this m 
of the machine continues unceasingly, 
external aid, so long as it is supplied 
and remains in repair. A small mnni 
necessary for this machine, as the 
should be kept at one constant eleratioi^ 
the perfeclinn of its action. A much greal 
tity of water likewise escapes at the o 
between the pulsKtions, than can be raised 
livery pipe X, particularly if it extend to 
siderable height, for the comparative q« 
water discharged through X, and permitt 
to waste at R. must always depend u 
spective perpendicular heights of 
column O V, and the delivered or 
W X, and the rapidity of the pa 
wioe depend upon the same ci 
Millington, from whose Epitome of X01 
sophy the above description is taken 
erroterl several of these machines in diffd 
of England, which gave great sstiofoctioR 
to show their efficacy gives the following p 
of one, which, at the time when he wr^tr, 
in constant use for abont two years : — The 
O is a basin of iboot 10 feet square and 3 < 
formed partly in limestone rock, and partly 
work, the supply of water being from 1 
spring. Tbe pipe Q is of cas; iron, II 71 



gmg 




MAGA/fNE OF SCIENCE. 



91 



ichea in diameter. The piece at the end, 
tug the air veuel and the vulves, ii about 
loof : the viWes 1) inches each in dia- 
aod made of brau; conteota oC the air 
iboat one gallon. The height from the surface 
vater mt O to ita puiul of diacbarge at R, ia 

inchra. oaeaa ured perpendicularly. The de- 
Ipe X ia of lead, I inch in diameter, and 
kboriKOotJilly under the ground 104 feet, and 
n prrpendicularly to the height of 54 feet 
I ftbove the diubarge valve at R, where it 

the water into a Urge cistern. The water 
nised 651 inches above the surface of the 
■hich vappliea it, and this bj a fall of only 
inches. So* circumstanced, the valve S 
iboQt fifty Tibrations, or opena l^y times in 
^ when it toees about two f^uurts of water, 
fctJt n<parly a qaarter of a pint into the 

cistern at each puUatioa; the water lost 
\ that wbieb ia raised nearly as 17 to 1 . Tbia 

ar a liniall quantity of water, but when it 

;ted that the machine is at work night nad 

lieu purposely stopped.) and furnishes six 

wftter every minate, this will be foQnd to 

ipply adequate to a very large hou<9eh(ild 

intent. The construction above dtscnhcd 

rcr, incomplete, as, owing to the mutual 
%tioa which lakes place between' air asd 

le successive quantities of water that are 

Into the ur vessel would soon absorb the 
F the air contiuned in it, and it would cease to 
tmt rUittirity which is indiMi>ensable to the 

of the machine. Tlits was discovered in 
by M. Mootgolfier, who added an improve- 
^Kbe machine by introducing a very small 
waive, opening inwards Into the lower part 
ir vessel, but kept shut by a small apring. 
bown to the separate shaded figure above 
l«scribed, ond represents an improved form 
ir vessel. This valve is srlf-acling, and 
ly prevents the escape of any air or water 
the Hir vessel [ bat when the wnter ii thrown 
the ahucting of the vntve S, it produces an 
leoos vacuum at the end of the pifie Q. 
ieh the shifting valve opens, and admits a 

quantity of the extrrnal air into the air 

keep it constuntly replenished, and by this 

diciun the water mm is rendered continu- 

action. 

pUGNEOUS ACID, OR WOOD 
VINEGAR. 

fnmptigeSil, and ctmciuded.) 

V viue(C"r produced by this disCilUtion is 
red ; it is now quite pale, and is even a 
Ity. [t Can never be rendered much purer 
Umw of ibe process ; for such in the affinity 
oil to tiie vin^ar, that they will Iwih rise 
U aiul come over together. The method 
ion adopted is engaging the vinefnr. which 
sent of the tar-oil, by meAos of ita aUrmty 
line substance. The liquor is accordingly 
ritber with lime or carbonate of limr. — 
auecrefls better, as it exerts no action on 
I. which, therefore, to a certjiin extent, 
, floats, and may be readily removed by 
The objection to carbooato of lime is 
r. When lime is used, it not only sntu- 
Acid, but it *»mbmes, in some degree, 
If -oil, ami forms a sapumiceous com pound : 
Vtt of tw-oil separates, and fioats, as 




in the former case. The solution of acetate of lime 
by saturation still further (lurified, and decanted off 
clear from any esrets of lime and a little tar-oil 
which falls, is evaporated to dryness in an iroo 
boiler. During the evaporation to dryness, etpe- 
uially towards the latter end, when the boiling pro- 
cess is somewhat elevated above 212", some tarry 
mstter is volatilised. The acetate of lime which 
results from this process is almost white ; it is iu 
small dry ma«M*s. 7*bis salt is intrfldured into a 
cast iron still with an earthen bead. The beak of 
the bend enters a large cask containing pure water : 
sulphuric acid is poured into ifae iron body, over 
the acetate of lime, and heat is applied. Vapors 
now arise, which are concentrated acetio acid, and 
which contain almost no impregnation of tar. These 
vapors pass over throegh the beak into the cask of 
water where they are absorbed ; the water betomes 
more and more acid ; nnd at length, when suffi- 
ciently iinprt^nnted, which is known by its incrcas« 
of specitic gravity, the wood vinegar is 6ni8bed. 

When well prepared, it has scarcely any peculiar 
smell or taste ; it ccmtsins no foreign vegetable 
matter, and is, tlierefore, purer than that from 
nmit, sugnr, fruit or wine. It succeeds better as a 
pirkhng vinegar, because it may be concentrated to 
any strength. It is perfectly transparent and 
colorless. 

The beat timber for making pyrollgneons vinegar 
is oak : but beeeh, ash, sycamore, and birch, an- 
swer exccedinRly well; in short, every kind readily 
procurable is found to succeed, except elm, and the 
diiTereut kinds of fir. A singular circumstuncc is 
asserted by the mannfacturem, namely, that elm 
timber, on distillation, does not afford acetic acid, 
but a watery liquor. Probably it atfordv a litilo 
acid, but so hide as to be inappreciable. Dry 
timber atTords a less abundant, but more valuable 
product. It should never be used in log, but cleft, 
as otherwise there would be much waste of fuel in 
permeating the large masses of wood by the heat. 
Taking the average of the different kinds of tim- 
ber, it may be stated, that the quantity by mciisure 
of tar obuiined, is about onc-twclfih of tlie product 
of the whole distilled liquor. The ratio of pyrolig- 
nenus acid can scarcely be determined, it dependa 
so much on the mode of applying the heal, the age 
of tlie timber, and various other circumstances. 

Generally speaking, a gallon of the liquor, as 
di<«tilled fruru the average charge of the retorts, 
afror>l:<, when saturated with lime and evaporated 
to dryness, about one pound of acetate of lime. — 
And a pound of acetate of lime, when put through 
the prticesa of decomposition, by sulphuric acid, ns 
already described, is capable of affording five pints 
of good house vinegar. 

Instead of the apparatus just described, namely, 
the cylmdrical retort, some manufacturers make 
use of tlic ordinary still, head, and worm ; the two 
former parts of the apparatus being made of cast 
metal, and the latter of copper. Various nxidih- 
calions of the apparatas have been also inlroriuced. 
Formerly, the inHammable gases generated duriug 
the distillation of the wood were allowed Co escape 
into the air; at present, they aro conveyed, by 
meAus of a tube springing from Ibe retort, tiitn the 
furnace where the fire is bunting, and thus contri. 
bute to heal the rcLurt, and cause a cortsiderable 
saving of fuel. In burning, the gas product* ■ 
flame possessed ot sufficient illumioating power to 
render ic an object of some consequeniT in this 
respect. The iufUoiuuble gaa comes over chirtfy 



MAGAZINE OF SCIENCE. 



during the last Itirre or four hours o( the diitilU- 
tinn. IL8 illiiminahnf power is at I'lrst very feeble; 
H then iocreaws; ia at iu tn&xitnum towards the 
■imI ; it then tudUfinly diminisbea ; in a abort time 
It docA not exrf rd that of the hydrogen; immodi- 
ttrly afifp, tbc flame goes out, 

TtiLTf 13 another prucem for purlfyiug pyrolig- 
neoits vinegar, nlitch hu been employed, and pre- 
sents a very pure aceltc nrid ; it ia thus described 
by Thfojird : — Ai much chalk ia added to the im- 
pure luid as can be decompo«ed by it at the ordt- 
nnry temperature ; a bUckUh-browu froth is formed, 
which is carefully rrmored. The liquor is then 
mndo to boil, aod the saturation is finished with 
lime. A proper quantity uf sulphate of soda is then 
added, which produces acetate of soda, and «ul- 
phitta of lime, the latter of which hnng iusoluNe 
preoi^tAte), and drawi down aJong with it oiure or 
less tar. 

^\ hen the atUph&te of Utne hae subsided, the so- 
lution of acetate of soda is dec-anted 09*, and is eva- 
porated to a pellicle ; on cooling, it concretes into 
a oryilolltnc mass. This is very impure : it ia 
bUck ; and ta fpreatly impregnated witli tar. It ia 
purifu'd by causing it to undergo the igneous fusion, 
re>dissu1ving it inwntrr, utid crystallising it at least 
ouL*c ; during the fusion, the tar is either volatilised 
or CMfbontsed, and the cry^uU formed are peroepii- 
hly purified. The crystals thua obtained are dis- 
frolvett in water, and sulphuric acid ia added : sul- 
phate of soda is producf^d, which crystallbes almost 
nnliivly ; and the mother liqnor, being diatiiled. 
alforiJ^ puro acetic arid. Tl^e specific gravity of 
the acid prepared at Choisy is 1057 : it is capable 
uf saturating about tliree-tentha of its weight of 
subcarbonate of soda. 

Hie following method of purifying pyroligneous 
acid hits been given by Berzelios : he saya that it 
may bo deprived of even the last traces of empy- 
reuointic oil by means of nninial charcoal. He 
found that the carbonaceous reaijnam left in the 
mahiMg of Prussian blue, wWn the prusaiate of 
pntash has been extracted, pnsftcsses this property 
to such a degree, and so cn*ectually removes Che 
etnpyrciiraotic taste, that the smallest qnantities 
ar<; suSirimt ; nml that it in only necessary to mix 
the acid with the rbsrcoal, and filter forthwith. He 
proved, itlsu, thut the arid (hua deprived does not 
lerovcr ita t^mpyrruma^ far some that had been 
loosely corked in a bottle was, after flvo monthi, as 
good as ever. 

Lowiut li>ne oira showed tlie porifying power of 
rommon chArcnal on pyroligneous acid. He says, 
**'rhi^ mi called acid of wood, which I obtained by 
distilhtliun from lignum vitic or guaiacum, was like 
vinegar very readily purified by distillaiion with 
rharrn^l, from the great quantity of empyreumatic 
oil which adheres to it. It thereby acquires the 
tjole and smell of distilled vinegar ; and after con- 
centratini^ it ta a very high degree by one of my 
new methods (freezing), 1 hare brought this acid of 
wood, as it is termed, to crystaUisc in the same 
manner as Tii)<>gar, and have thus obtained a true 
glatnal vinegar." 

It !(«» bren atccrtaiiicd that pyroligneous acid in 
its unpurified stnt.: possesses the remarkable and 
usrful pmperty of prtvcniiiiQ the piitrefsctiDu of 
anitnat Auhttsures, and etcn uf clitrckmg putrefac- 
tion when livt;iin. It has been always known that 
srookud provisiuus keep better than those which 
have been dried, an efl'cct which seema to depend 
on the imprr^nation of pyrolif^itoue acid, which 



they receive from the rmokt ; for it t» turf emoki 
that IS rmployed, and tnrf b; dttflillalion in dose 
vesseis affords pyroligneous acid. The fullimtac 
account is given by Mr. Hamsay of npcnmwiu 
made by him : — A number of herrings were rle«Deil 
Ofl the lOUi of July. 1819. and. without bcini^ saltrd, 
were immersed for three linurs in ■' * '- ' — 
ncooa acid (sp. gr. 1012). '\Vheik 
were softened, and not ao firm a* ^ i 
out of the common pickle. They were bun* up u 
the shade. July and August wf re very hot mnndis 
— but the herrings had no sign of putrefaction 
aboat them, but had a very wbulesome smell roo- 
hined with that of tlie acid. One of them hciii| 
broiled, the empyreumatic aaell was very atniBig. 
The rest, in six months, were in complete pnHiw. 
vation. 

U was afterwards found that the period cf li^ 
mersion had been too long. If the fish be sbnpl| 
dipped in acid of specific gravity 1012. and dned 
in the shade, it ia sufficient fur their preserMAtt) 
and Hurh herrings when broiled are very a, 
and have not the disagreeable empyreomatic of 
former. 

A number of haddocks were cleaned, split, 
slightly sprinkled with salt for six hours ; tlinn ba> 
ing drained, they were dipped, for about 
seconds, in pyrollgneont acid, and hung in the 
for eight days. On being broiled they wera of 
uncommonly fine flavor, delicately white, andeusd 
to the highly esteemed Fintun haddock, no- 
rings wer« t:ure<l in the same way as the 
After beini- dried iu the shade for two moathl, tkm 
were equal in quality and flavor to the best ni 
berringa. The fiah retained the shining and fi 
appearance which they had when taken from rhe 

A piece of be«f waa dipped for mie 
pyroligneous acid (sp. gr. IU12) in Jti' 
On March 4th. 1H20, it was as firce from t 
when first immerted. No salt was oaed in 
periment. A piece of beef was dij*;"*' '* '^ 
time in pure vinegar of specific ;-! 
was perfectly free from taint on tin; 
her. This experiment indicates sntiiwpHc: 
in pure vinegar ; some haddocks wcrv cured with 
which remaioed free from taint, and. nheaooo' 
had an insipid taste. 

Dr. Jorg, of Leipxig, repeated acme of cfaese 
perimenta, and with success. He even 
perfectly in making BDatoinical prBpmratMHW 
pUcation of pyrolig;neotts acid. 

It has been already stated, tbst ia the 
distillation of the pyroligneous acid, Ifae 
duct that comes over is of a peculiar miture* 
rjilled wood.ftjnrii. This is purified by 
ttllations from some alkaline subatancr, 
from oxyde of lead ; and when aufficiciOly 
it assumea the appearmnca of a tnmapsfial 
nearly colorlesa fluid, poaaessiog msoy of 
pcrtiea of alcohol. At first it waa 
tical with aleobot ; bat there an pointt of 
ence. It ia highly inflammable) aod bamo 
pate flame, emitting very little light. It 
culiar penetrating smell, and a *trutig 
ethereal taste. It disaolves Indian rubber, 
forma a varnish applicable to a variety o< "'■'*■ 
This solution of Indian rubber is alao > 
manufacture of a useful and beautiful v- 
wooUen cloth. Wood-spirit dissolves reaiasc 
hence is used, by some makers of watcr-proflf 
as a leas expensive 
their nroccu than ali 




MAGAZINE OF SCIENCE. 



9f 



•spirit tft aiUled by cbeniuts pyrortlic 

-...I :.:^^ fronj nitiriate of Um«, JL is 
gi . It boil* at l.'iO"'. It burns 



l'- 



Dy reaiiiuum. 



ATALANCHER. 

of the great and rarioas phcnomnit 
V irogbt not to omit tho»r tremcndoufl 
drstmction, the nvalanchri, prculiJir to 
countries, tlutt frttqucntlr clo6c up 
lUeji ; nllKT the courvea of rivers, and 
fcheir oTerwfaelming maitscB, entire dia- 
their towns. viUfifes, and inhnbitinta, 
hurry into eternity without a moment's 
ice. 

I which ure subject to tlie particular 

fraUnche, sometimes termed ■ I^and-Mlip, 

itghi-bcrg and Ross-bcrg, are usually 

M Breccia (which seeniB to be u conglu- 

■ Band and stooes, more or less firmly 

Ikgetber), that is peculiarly liable to be 

y rains and rrost, siid even by droughts, 

r«d to open in large fissures, that soon 

by the melting: of the snows, or by 

in tan\ being acted upon by frost, bursts 

I detaches hagcniiuses that^come rolling 

noise like thunder, bearing ererything 

into the vnlleyn beneath. Thi$ pro. 

ler expanding by freezing, is so well un. 

Roaaia, that in some parts they avail 

of it* aa we dn of gnnpowdcr, for the 

. rodca — alt that Ja necessary being to 

^a. aa in the other case, in the direction 

it to split, and thus Ichtc it to nature l<i 

rrst. The apertures ore soon filled by 

rhich fall in Uh: early part of winter, Htiil 

sdTaoces, the work is completed by 

IVeca ond roots, which are often of a 

there* arc frequently i^plit by the same 

^ro lo the subject, another powerful 

operates conjointly with the others in 

[great renta in theae mountains, is found 

txamaUtioa of vast niiuues of cungenled 

adhere to the peaks and overhanging 

neight of which is often sufficiently great 

mountain to separate. This whs sup- 

T been tlie case with one at the RaaB> 

took place at p. ra., on the 2nd of 

1806, as it was particularly remarked of 

e had been almost a continued full of 

the months of July and August pre- 

aeded by hciivy rains, and snbseqoently 

en load reports like the cracking of the 

been heard at different times. The 

however, which had, no doubt, 

taoaped obMrvntion at the time, from 

Vtance of tlie rauuntAin being thickly 

Kb wotHl. On the day on which tlie 

occtnred, not more than thret or /our 

1 any intimation of what was going to 

loae people were at work on the lower 

Boonlain, but being alarmed by the in- 

« they heard, and hnnlly by a vibra- 

ri itself, they had only time to 

-, wilLuut being able to afford 

v.. u.. Ttllugea and^ inhabitants that 

At last the mountain was 5ccn to 

the whole 4>f thitt pure wbn-h e:ttendei) 

^pitzbugiU and The Steinbergrrrtonc. 

ood came down, bnaging with it a 




whole fbrcal of trees, with a horrible crash, cover- 
ing nearly two-thirils of the beautiful, smiling, and 
hitherto peaceful valley of Goldau, ond a Bmrtll part 
of Bonsingheo. to a depth of perhaps '201) fret, and 
burying ander the niins the Tiltaf^es of Goldau, 
Rousinghen, Ober-Roethcn, Unter-Roelhen, ami 
Lowerts, together wiih their inhabitants, formerly 
so celebrateil in thcAo [wrta for their fine appear- 
ance, their bravery, and frugal and iadustrioua habits. 
Fovr Aimdre'l and Ihirhf-thtrc personit are known 
to have periihed on this unfortunate occasion, in- 
cluding tixfeen tonrists or strangers from vuriona 
parts, and eigM individuals that were known to bo 
there from Berne and ArEovi(^— whilst about Jhe 
hundred and thirty more were ruined by the entire 
destruction of their property; and what added to 
the loss of the latter, was the circamstance of some 
part of the debris having fallen into the western 
part of the lake of Lowertx, and forcing out the 
waters upon the land, swept with tUem, on iheir 
return back into the lake, many hoaaes with their 
inhabitants, that were placed m iu vicinity. The 
hltle valley of Goldan, which, before this, was con- 
sidered one of the most beautiful and fertile in all 
!<!witserland, is very narrow, having on oppofite 
fl1de«, the Rigbi. and Ross-berg, and is about two 
leagues in length, terminated at one end, by the 
lake of Zoar — and at the other, by the lake of 
Lowerti. Of this extent, about one leagne was 
covered over by the avalanche, and so completely 
did it reach across the valley, that the base of the 
Righi on the opposite side waa covered up to some 
height. 

Of this dreadful event, a traveller writes «a fol- 
lows : — " Whilst walking on the ruins of the moun- 
tain, which are heaped in horrible confoaioD on this 
spot, and. over which, a road has been cat to Art. 
it prevents to our view masnea of nibbtsh and rock 
(some aa large as a house), indiscriminately piled 
on each other, and intermingled with fragments of 
trees, of which some were seen with their stems and 
branches fixed in the earth, and the roots in the air; 
and bemmnl in us this valley la by monntains ot> 
each side, one seems to contemplate here the wreck 
of all the visible and material world around. The 
force, too, with which some of these tmmenae block* 
descended, muat have been very great, when we 
consider that the height of the Rosa-berg was about 
3,500 feci; and it was a melancholy thing to redect, 
that under the apot on which we were now tread- 
ing, were conceded for ever from our view thoae 
peaceful villages, with their inhabitants, who were 
surprised amid their peaceful and domestic occupa- 
tions, and hurried in a moment from the light of 
the world/* 

A gentleman of the town of St^hwitz, in thia vici- 
nity, who collected many affecting detatta of thia 
event, aaya — that in that town sncb was the 
uproar and noise it made, rrverbemted by the 
nnrrounding mountains, that the people actually 
thought the end of all things was arrived ; and tlita 
isi not tu be wondered at, when we are informed 
that BO great were the clouds of dast, of snow, and 
of water, which it sent up, that the air waa com- 
idetely darkened, and the sun hid from their sight 
for the remainder of that day. Amongst others 
which he mentions, the case of a [loor girl and a 
rhild are particularly remarkable. Tliey were walk- 
ing together in the garden of their cottage at the 
time the catastrophe happened, and the only oc- 
(ount of it the x;irl could ^ive, wmh, that she founil 
herself in an instant in the aituatiou innhiclisUe 



94 



MAGAZIKE OF SCTEI^CF. 



wtfl discoTrred, with hrr body j«romed in the earth, 
her heHd duwowardi, uid her feet ia (be air In 
this frightful pokition, her eyM forced frnrn their 
tooketji, and stretroing with blood, did thi& poor 
girl rcrniin for teTeral houn, during wfairh shecnn- 
versed with, and endeavoured to pacifv the child, 
which cried piteoasly for food, and which she found 
wan covered over by a «toue near lo her, and un- 
hurt — at tirst she tried to peniuade it to go lo »leep, 
and that some of the family werr coming to its re- 
lief — but despairing at last of thit, she encouraged 
it to say its pravcrr, and they were thus engaged 
together, when tbey were ditcovered by the subbing 
and crying of the child, which fortunately directed 
some people to the spot, who had gone out from 
Schwitz to »fe if there were any left to whom thry 
could afford succour. It is interesting to humanity 
to learn, that this poor girl actually survived, 
though with a total deprivaiion of sight, and a 
dreadful horror of the event ever afterwards. She 
haa of often said since then, that the greatest pain 
ahe felt during the time she was covered over, wan 
ftrom the excessive cold in her feet, which it appeara 
was the only part of her that was found uncovered 
and exposed to the air. 

Id varioaa parts of Switzerland, accidents of the 
kind here described, are perpetually ocrurring, and 
it waa only five years before, viz. in I HO I, that a 
considerable one took place in this neighbourhood, 
from the Right, near to the hnmlet of Sigiker, at 
which time a large portion of the mountain was 
precipitated into the Lake of Lucerne, which re- 
pelled the waters to such a degree, that by their re- 
Mux upon the land, they swept away several houses, 
atabling, and saw.millR, pUred at some considera- 
ble diatance from its banks; by which eleven per- 
sons are said to have perished. The agitation of 
the waters of the Lake on this occasion, are re- 
ported to have reached even lo Lucerne, a distance 
of, perfasps, six or seven miles, and did some 
damage to the shorea on the opposite side of the 
Lake. 

In point of extent and consequences, one which 
occurred lately in the valley of Bngnes, deserves 
to be mentioned, as it was attended with circum- 
stances very peculiar. This valley being very 
DBrrow, and almost entirely occupied with the river 
Drance, was stopped up near its source, by an 
avalanche, and the river being in consetiuenre dam- 
med up, a vast accumulation of water had taken 
place, so as to form a lake of considerable size be- 
fore it waa discovered, owing to tltc retired situa- 
tion of the place, ud being but little frequented 

As soon, however, aa it became known, it created 
a great sensation for the safety of the conn try, and 
the inhabitants along the whole course of that river, 
to where it joins the Rhone, above Martigny ; and 
afterwards to the Lake of Geneva, where the Rhone 
enters the latter near to Villeneuve ; a total extent 
of 14 or ir> leagues, and this was not without rea- 
son, considering so vast a body of water, and the 
force with which it would descend, if let loose sud- 
denly from so great an elevation amongst the moun- 
tains. Public meetings of the inhabitants were in- 
atantly convened, and as the danger was pressing 
and hourly increasing, experienced engineers were 
employed to effect the making of a tunnel, by which 
to draw off the waters graitually ; when it was 
supposed the impediment might be removed, and 
the progrean of the work, as it took place, was 
regularly Muti6fd to the people, and signals esta- 
blished along the whole line, to warn the inhabi- 



tants when the danger should seem re 
so as to enable them to rnnore tbei 
their storks, to places of safrtv. Not 
the excellence of these regulationt, 
danger could not be averted entirely, 
work waa considerably advanced, the 
throngh the tunnel, blew it up, and mpta 
hy which the nhole body of the water 
pcctedly set free, carrying away bridge 
habitants, with their cattle and gooib, M 
everything that was opposed to it 
lengthened course towards the lake. Al 
and Idm of lives it occsaioiied were vei^ 
the particulars were pubhshed in all ihfl 
at the time, we need not occupy our 
recapitulritiou; but the loss of livrs wt 
still greater, had it not fortunately 
very early hour, before the workmen 
to commence their work. Two of oor 
and their guide, who had gone up 
works early that morning, are aaid 1 
the unfy persons who witnessed tba 
escaped, by proceeding rapidly up a pr 
in such haste, tliat the horse, belongia| 
them, was lost. Certain it is, they 
terror to Geneva, and were the firvt 
accident known there. 

Another kind of avalanche is that 
posed almost entirely of congealed i 
and which ia so frequent riiout 
Chamouny. and other places, wbers 
glaciers ; that these valleys an* coustani 
ing with the noise of the falling bodies, 
re-echoed hy the mountains around, 
hke thunder ; and in some confined pli 
bration which is occasioned in the a 
firing off a musket, will sometimes 
siderable portions of it. When any of tl 
of snow arc sufficiently large to block 
or road, whirh ia of frequent occui 
come so condensed and (irm, owing 
weight, and fulling from such trcmeodi 
that a traveller on horse-back may pi 
in aafety, without fear of ainking. 71 
Valoraine and Tete-noir, was once clot4 
avulnuche of this nature, under wbid 
Trieni had worked itself a pissage, fiaf 
gutar arch through its whole extent, 
bridge travellers had occasion lo cross 
back more than once ; and in one or 
where the arch had fallen in. they 
near enough to look through the openii 
the torrent spending its rage underneath 
in the month of May, when the sua 
to be powerful, and a week after its fall 
few days more, they said it would be 
for about three weeks or a montb, after 
Ihc whole would disappear, and be 
the riwr. 



OF GASEOUS ANALYSI! 

This deportment of -chemtatrv, wh 
portance was l^rst shown by Cavendiril 
and BerthoUet, baa lately acquired ni 
consequencT of M. G. Lusaac's doctrine) 
his determination of the specific graritiel 
and sagacious application of both prnic 
derelopement of many combinations hit 
cate and inexplicable. 

Let us first take a general view nf thv 
of the different gaaea. Some of Ihea 



IIAGAZINE OF SCIENCE. 



95 



itf white vapori in the air; sotnff relume 
rilled k paint of its wick remnins i^nileil ; 
Did and redden tincture of litoiu» ; one 
imell. or bat ■ fnint one; a ai^rond set 
Ittble in water ; b third Nre suluble in 
ationBt and a fourCb are tbemaelves 
Somtt guei posaeaa aeveml of these 
t onoc. 

ttored goMtM ore nitrouii acid, chlorioe. 
le and deutnxide of chlorine. Tbe firat 
eat yellowish-green, or yellowish. 

produeing trAi/e vapora in the air. 
d. duoborie, lIuoHilicic. and hydriodjc. 

mfiammtUtle in air by contact of the 
r. Hydrogen r labcarbaretted and car- 
IroKeo. I ubphospbu retted and photphu- 
%cn, sulphuretted hydro^n, anMmuretLed 
lUuretted hydrogen, potauuretted hydro- 
}ua oiide. pmnine or cyaDogen. 

which re-kindle the expiriag taper. 
Dtoxidc of asote, oitroiu add, and the 
loriae. 

{[aaes, which redden litmua. Nitroua, 
nufiatic. fluoboric. hydriodic. lluosUicic. 
lOua, and carbonic acid ; the oxides of 
phuretteii hydro^^n, telluretted hydro- 
isaine. 
dmMtUute of nmelit or possesKing hat a 

Oxygen, azote, hydrogen, lubcarbu- 
carburetted hydrogen, carbonic acid, 

axote. 

lall of aU the others is iniap portable, 
Ij frharocteristic. 

Krry Bolubit in water, namely, of which 
es more than thirty times its volumn, 
reaanre and temperature. Fluoric acid, 
Mtlicic, oitrous, sulpharous, and am- 

§oMiU in atiatine soluttoni. Acids, 
huroufl, roariatic, fluoboric, hydriodic, 
llorine, carbonic, chlorocarbonoaf ; and 
e« of chlorine, lulphurettcd hydrogen, 
rdrogen, and ammonia. 
m9 gaaes. Ammonia and potaasuretted 

general outline of the chnracteristics of 
The great problem which now yrtttentt 
Ulermine bt/ eTperimenU the nature qf 
IS, or goneiiiu miiiuret which may come 

U a little glasa tube with it. and expose 
on of a lighted taper. If it iaflam», 
iie eleven above enumerated, and must 
ited by tbe following methods : — 
dees fire spontaneously on contact with 
g a Tery acid matter, it '\* phogphuretted 
Sabpbospharctted hydrogen, or the 
; of phosphorus, does not spontaneously 

!r b« capable of decomposing it, and 
it aaddeiily into hydrogen gas and 
I we can eaiily ascertain by transferring 
5Uod with it, from the mercurial trough, 
containing water, it is potaaturetted 
Dr Ure found in experiments on the 
f poiaasiuni, by passtn)^ pure ))Otash over 
turnings, of which nomc account was 
t 1B09, that potassuretted hydrogen 
y inflamed. M. Sementioi has made 
terra tt on. 

•aa a nauseous odour, ts insolable in 
i Oft the aides of the t^st tube in which 



wa hnm it, a ehcRnut brown deposit, like hydmret 
of arsenic, and if, after a^ptation with tbe quarter 
of ita Totamn of aqaeons chlorine, a liquid is formed. 
frt)m which sulphuretted hydrogen precipitatea 
yellow flocculi, it is artenurelled hydrogen got. 

\, If it baa a strong atuell uf garlic or pbosphonaa, 
if it does not inflame sputitaneously, if tlie prodnct 
of its combustion strongly reddens litmus, and If, 
on agitation with an cxcesa of aqueous cblurinr, a 
Liquor result!!, which, after evaporation, leaTca n 
very sour syrupy residuum, it ia ntbphosphuretted 
hydrogen. 

b. If it hss no smell, or but a faint one, and if it 
be capable of condensing one-half its volamn of 
oxygen in the explosive eudiometer, it is hydrogen. 

6. If it has a faint smell, be capable of con- 
densing in the explosive eudiometer oue-half of its 
volumn of oxygen, and of producing a volamn of 
carbonic acid equal to its own, which is ascertained 
by absorbing it with aqueous potash, it is carbanou* 
oride. 

7. If H has a faint imell, if one of the products 
of combuation is carbonic acid, and if the quantity 
of oxygen which it condenaea by the explosive 
eudiometer, corresponds to twice or thrice ita 
volumn, then it is either tubcarburetted or carbu- 
retted hydrogen. 

B. If it diffuses the odour of rotten eggs, if it 
blackens solutions of lead, if it leaves a deposit of 
aalpbnr when we bum ii in the test tube, and if it 
be absorbable by potash, it ia sulphuretted hydrogen. 

9, If it hns a fetid odour, approaching to tliat of 
sulphuretted hydrogeD, if it ia absorbable by potash, 
if it is soluble in #iiter, if it forms with it a liquid 
which, on exposure to air, lets fall a brown pulverulent 
hydruret of tellurium ; and lastly, if on agitation 
with an excess of aqueous chlorine, there results a 
muriate of tellurium, yielding a white precipitate 
with alkalis, and a black with the hydrosulphureta, 
it is telluretted hydrogen. 

10. Pnutine is known by its offensive and very 
peculiar smrll, and itn burning with a par]de Hame. 

If the gas be non-inflammable, but absorbable 
by an alkaline solution, it will be one of the Ihirteao 
following : muriatic acid, fluoborio, fluoailtcioi 
hydriodic, sulpharous, nitrous, ohlorocarbonooa, 
carbonic ; or chlorine, the oxides of chlorine, 
prussine, or ammonia. The firat four, being tbe 
only gaaes which produce white vapors with atmos- 
pheric air, from their strong affinity for water, are 
thus easily distinguishable from aU others. The 
Jtuoritieic ga* is recognised by the separation of 
silica, in white flocculi, by means of water ; and 
hydriodic go*, because chlorine renders it violet» 
with the precipitation of iodine. 

Murintic acid gan, from its forming with solntion 
of silver a white precipitate insolable in acids, but 
very soluble in ammonia, and from its yirlJing with 
oxide of manganese a portion of chlorine. Fluoborie 
gas, by the very dense vapors which it exhales, and 
by its instantly blackening paper plunged into it. 
Nitrout acid gat is distinguished by its red color. 
Prutojide of cJi/ortne, because it is of a lively 
grernisb-yellow hue, because it exercises no action 
on mercury at ordioory temperatures, and because, 
on bringing ignited iron or glois in contact with it, 
it is decomposed with explosion into oxygen and 
chlorine. 

Dtutojride qf chlorine is of a still brighter 
yellowish -green than the preceding, and baa ■ pe- 
culiitr aromatic smell. It does not redden, but 
blaochea vegetahle blues. At 212^ it cxplodea, 




9$ 



MAGAZINE OF 8C1KNCE. 



evolving oxygen and cliloriae. (^Uurine U ilit- 
tinRiiifihfd by its fainter 7«llanrish •green mlar, by 
iti lutlcring no change on beini^ bested, by iti dc- 
•Cruytiiie: C(»)(iri, and by its rapid combtnaCion witli 
niereiiry at common tern perntu res. SH^hnrott* 
and, by ita smell of burning aujphur. Ammtmiaj 
by itA odour, alkaline propertiea, and the denae 
while vapors it formfi vriih gaseoiu acids. Cftlon^ 
caHnmoug gn» ii cunvertcd by a very »mail qiiaittity 
of water into a<)acou.i( muriatic acid, and (urbnnir 
ftdd, whicli Tf^Xti above. Zinc or antimony, aided 
by beat, resolvea it into carboooiit oxide giu, whUe 
ftSoUd metallic chloride ia formed. With tlie oxides 
of the fame motaU, it forms chlorides, aod carbonic 
add, while in each caac tUe qanntity of gaseous 
oiidc of carbon, and carbonic mad disengaged, is 
equal to the vuluwn of clilorocarbonousgss operated 
on. Carbonic arid ffot is colorlesi, aitd void of 
siDcU, while oil the other gam-s absorbable by tlie 
alkalis bave n ttrong odour. It hardly reddenf cvtn 
very dilute tmcttirr of litmus ; it gives a white clood 
with lime water, from which a precipitate falls, 
•oluble with (iflerTpscfnce in vinegar. 

[f. linnlly. the gas be fneiiher iDflsmroable nor 
capable of being absorbed by a solutioii of potash, 
it will be oxygra, asote, protoxide of azote, or 
deutoxide of nsole, Ojypen can be mistaken only 
for the protoxide of azote. Thu property it posaesaea 
of re-kiodling the expiring wick of a taper, dk- 
tiDgaishef it from the two other gases. They arc 
moreover charanteristid. First, btcaosc oxygrn is 
void of tasrc, and capable of condensing In the ex- 
|dosive eudiotnelt^r twice its Iploiiin of hydro^^en 
gaa ; the protoj:id*^ qf' azote, taVauBe it has a sweet 
taste, is soluble in a little less than half its voluma 
of cold water, and because when dctonHted with ita 
nwD vnjamn of hydrogon, we obtain a residuum, 
c^mtaining much ajsote. The two other gases are 
distingui<ibcd thus: — Deuloride q/'oso/e iacolorlesa, 
and when placed in contact with atmospherical air 
or oxygen, it becomes red, puniug tu the atate of 
nitrouH iicid Tnpor Arotr ie void of color, smell, 
aad taste, extinguishes combustibles, experiences no 
change on contaiet with air^ aod produces oo cloud 
with lime water. 



ON BEN NUTS. 
BsN Ki'iv are the fruit of a tree which f^rowa Id the 
Indies, Ceylon, and Egypt. Linnieus calls it guU 
Umdia moringa; but Lamarck has changed it to 
mormga Znlinica, or M. oiei/va. Its fruit is a 
three-volved pod, full of a white Hesfa. and a number 
of three-cornered seeds, the sixe of Urge peas, co- 
vered with a thin, tott, whitish-grey shell ; these 
seeds coDtoin a white oily kernel, of a very sweet 
taste. 

The oil of ben ii obtained by pressing these nuts : 
this oil is swoet, loentlees, and scarcely ever be- 
comes muk ; by cold it separates into twu parts, the 
one solid, the othtr li(|uid. 

The property pouesied by this oil, of not becom- 
ing rank, has made the watchmakers use the lujuid 
portion of it for oiling the wheels and other wurks 
in watches and clucks. Nevertheless, partly on 
acconut of the difficulty of procuring good oil of ben, 
and partly from other motives, many watchmakers 
use at present the best salad oil. 

The oil of ben is used by the perfumers of the 
countries where the tree grows, not only because of 
its keeping so well, but also because, having no smell 



uf its owD, it th>es not alter that uf t}ie*roinati<! s«A- 
stsDoewilh which they tmprrsrn''' ■' "n.r^ i,* *k. 
flowers of tuberoses. jcfMun 
aceiiled flowers, wbi^h yield u 
in beds, in a clove pewter vessel, along muk 
cotton soaked in this oil ; the reasel is Chen 
for some time in boiling water. When th« 
judged to have Itub^bed tlie scent, it is 
from the cnttnn by llie press. OiJs thus prepsMrf 
nre L-ulled AuUrs antiqum, as being the oldest mednd 
of prrpinng scented oils. But the perfumenu 
the uortli of Europe mostly imitate these oils, ky 
udding easeutiaJ oils lo the best salad oil, or tu AS 
oil : and, in tome cases, by ahaking up eithwr of 
these oils with spirit of wine distilled off the flo«er«i 
Kheii the oil abaorhs the aroma of the flowcn Mot 
befwmas scented. Thase svhetitutioos render the 
nil of ben R-arce in the cooatries where the liM 
does not grow, by diminishing the demand fur it 



MISCELLANEOUS EXPERIM 

DfLAVr n landscape with Indian ink, and 
foliage of Tegetables with muriate of cobalt,,^ 
some of the flowers with acetate of cobalt, 
others with muriate of copper. \\Tille this 
is cold it will appear to be merely an ootUaei 
landscape, or winter sceoe, bat when gently 
tlie trers and flowers will be dupfagtd m 
natural rolorK, which they will preserve Oftly 
they continoc warm. This may be often 

Write upon paper with a diluted solution of mV' 
riste of copper ; when dry, tt wUl not be visible 
but on being warmed before the fire the writiag viH 
become a bcnntiful ye//mr. 

Into a large glass jar, inverted upon a flot bnci 
tile, and containing, near its tup, a limiuli 
rosemary, or any other such bhrub, moislcntJ «J 
water, introduce n flat (hick pieoe of heated 
which place some gum benzoin in groas poi 
The benzoic acid, in consequence of the hta^i 
be separitcd, and ascend in while fumes, which' 
at length condense, and form a most beantitf 1 
pearaoce upon the leaves of the vegetable. 
will serve as on example of mblimation. 

Mix a little acetate uf le^d with an njunl 
of sulphate of zinc, both in flnc powder ; stir 
together with a piece of glu^is or woo^l. and 
chemical change will be perceptible ; but if ttap 
be rubbed together in a mortar, the two sr>bd« m 
opcnitc upon each other, an intimate union td 
take place, and a Jtvid will be froducett. If i 
or Glauber ault be used instead of sulphate of iltali] 
the experiment will be equally surcessful. 

Curious Motion produced in Liquids by Hntm§ 
and Cooling them. — Fill a large phial with wi 
and put into it a smalt quantity' of powdered 
having previously added to the water a 
quantity of potosh, to make a solution of the 
suecific gravity ss amber. Immerse the pMll 
giBBS of hot water ; upon which a vvry 
internal rnotioo will he immedistelr perccii 
current of the fluid will rise up the aides 
phial, and another descend in the centre of it Kl 
take the phial out of the hot water, and obtcrrf tW 
cffectsof its cooling. The currents will tf 
the external one will descend, and the in 
ascend. The use of the powdered amber i« 
the opposite currents into which the water is 
visible. 



LsMOOM :— Printed bj I> FajLMCii, 6. Wbilf Uona Laos. UU« £Bd.-4*ttbliiheil by \V. SairzAiM, II. I'alai 



Bv*. 






THE 



AGAZINE OF SCIENCE, 

Stnii School of ^rt0. 



•ATlTKt)AT. JUKE M. 1841. 



[IK 




9S 



MAGAZINE OF SCIENCE. 



ATTWOODS MACHINE. 

FOR ASCKIITAJNINO TUE LAWS mCLATIVX TO 
rAXLtlCO BODICS. 

A RSrKKSXNTATiON^ of thii buutifal and nsrful 
suatriTance is given ia the engraving. A B C U 
ibe rim of the wheel over whtrh. the ihrrad sua- 
taintng the weighta paast-a. Tlic enda uf thr aile 
of this wheel rest upon the rims of two pairs of 
wherif, at h rcprrsentcd in the ftgun-. The itnnd 
oarrjtng the apparattia ia EiippnrrrJ by a strong 
pUlnft and imiuediately under tliia tittiiid ia placed an 
upri)[ht ahaft. divided into inches, Iialf-inchcs, and 
tenth*, for the purpose ofmeaKiiring the rate of de> 
scent. E and F are two eqaal cylindrical weights 
fttupended from the ends of the thread, which rests 
in a groove on the edge of tlie wheel A B. H ia a 
imall stage which can be screwed upon the gra- 
dnnted ihaft. at any particalar division at which it 
Is designed to stop tlie dc&cent of the weight. G ii 
ft clock, attached to the principal pillar, which beats 
Moonds, in order to mark the rate of descent. 

The wcigliU K P are, commonly, ao adjusted, 
that, by placing on the top of the cylindrical weight 
F a weight O uf a quarter of an ounce, the weight 
F will descend Ibroagh three inches in one aecund. 
Thus we hare obtaloed an ac<:elurating force, which 
b sixty-foor times less than that of gravity, and yet 
which retains all the characteristic pecnliaritiefl of 
that force. In fad It u the force of gravity oor* 
icctly rcpreaented in miniature. 

We shall now show how this machine Is applied 
lo estabUih by experiment the laws which regulate 
Ihe descent of heavy bodiei. 

Ex. 1. — To establish these lawi by experiment, a 
ring I is provided, Bttache<l to a bloclc 1), which rnn 
be Axed by a screw to any division of the grudaated 
shaft. A bar of metal J ii also provided, weighing 
a quarter of an onncf?, and longer than the diameter 
of the ring I. I-/ct the ring I be (Ued by the vcrew 
to any division of the icdle, and let the ytnge H be 
■o fixed, that when the weight P rests upon it, the 
top of the weight will be six inches exactly below 
the ring I. This done, let the weight F be elevated 
by drawing down the weight E, until the top of the 
weight K is exactly three inches above the ring I. — 
Holding the weight F tn this position, let the bar J 
be placed upon it, and observing the heats of the 
docli, let the weight F commenre its descent with 
tnybeat. It wlU be found that the stroke of the 
bar J on the ring I will exactly coincide with the 
Dext beat, and that the stroke of the weight F on 
the stage H will coincide precisely with the succeed- 
ing beat. It will be observed, that the accelerated 
motion of the weight F for the first second,, and 
before the bar strikes the ring, is entirely owing to 
the action of tht force of gravity on the bar. When 
the bar is taken off the weight P by the rin? at the 
and of the first second* this cauee of acctleratioa 
ceases, iha aetion of gravity is ituspeodedf and the 
weight F moves oo to the stuge If with the velocity 
which it bad acquired at I. Now we hitve seen 
that this velocity was such that it moved through 
six inches in one second. 

Kr.2. — Again, let the stage be placed so that whan 
the weight F re«a upon it, the top of the weight will 
be twelve inches from the ring I, and let the wei|;ht 
K be depressed until the top of the weight F is 
twelve indies above the ring I. This done, let the 
bar J be plaoed on the weight F, and let that wright 
he disengaged at the moment of any beat of the 
eluck ; it wtll be observed that tbestroka of the bar 



a is£ 

-I 

atV 

"J 



J upon the ring I. will coincide exact 
third beat, tlie desrent through twelve ' 
made in two seconds, and that the 
weight F upon the ataje II will roinct* 
with the fourth heat, the weight moving i 
twelTc inches below the ring with the vt 
acquired in two seconds. 

Rx. 3. — Now let the stage H be 
moved, and pliced so that, when thi 
standi upon it, the top of the 
eighteen inches below the ring I. 
E be depressed until the top of the 
twenty-seven inches above the stage ~ 
bar J be Then plac«d upon the weight 
and permittini; the wctgiit to cooiiueni 
with the firec beat of the pendulum, 
strike the ring I mitli the fourth beat, mni 
V will Ktrilie the stAge U with the fifth 
weight, therefore, descends thnmgli 
inrbcH vritli an accelerated motion in Ihf 
and, at the end of that time, has acqiiirfi 
veiocity, aa to move through eighteen is£ 
second. 

Now let us review the results of thi 
penmentf. By the first it appears, that' 
acquirnl in one second b surb as to maki 
F move at the rate of six inches per 
the second experiment it appears, that th4 
acquired in two seconds is twelve inches |i^ 
md, by the third experiment, it ap| 
velocity acquired in three seconds is ei| 
per second. Thus the velocitaes aoqt 
two. and three seconds, are as six, 
eighteen, which numbers are as «nei 
Hence the law that " the velocities sec 
the time of acquiring them," is verifii 

In the first experiment the weight 
three inches in one »econd ; in the 
mrnt it fell through twelve inches in ti 
and in the third it fell through twenty-scve 
in three seconds. Now the oumben three 
and twenty-feven, are as one, four, and niii 
are the squart-a of one, two, and three, 
law that " the q)aces fallen through are 
to the squares of the tiroes," is verific 

la the first experimcot it was sbol 
velocity acquired in falling through 
was such aa would carry the weight 
time through m inches when eontioi 
and without further increase. In the 
periment it was shown, that with the 
quired in falling through twelve 
seconds, the weight F would move thi 
inches in one second, and it would, th( 
through twenty-four inches in two 
like manner, iu the third experiment* 
that wirii the V4>locity anquired in 
twenty-seven inches in three seconds, 
moved through eighteen inches in one 
therefore, would move through fifty-fa 
three seconds. Each of these rxperir 
fore, verifies the law, that, " with the 
body acquires in any time, it woafd, if U 
city were continued uniform, move tt 
that spare in the Funie time.'* 

Also by the first experiment it sp[ 
space fallen through in the first raeoiuf < 
was three inches. By the second ex| 
peared, that the space fallen 
two seconds was twelve inches. It 
foUowi, that the apaoe fallen through- i 
second must bsvs been nine inche*. 



MAGAZINE OF SCIENCE. 



99 



tfaetptee fallen throuich in three leconds 

ity-Acvsn iiichra. TAing from this the 

tm throagh \a the tint two seconds, which 

re inciu^*, the remainder, lifteeu inchei. Is 

faUen throogh in the third second. Thus 

described iu the first, second, and third 

of the fsll &re three, nine, and fifteen inches 

tnlf, which are as tlie numbers cue, three, 

!. This verifies the law that " the spaces 

by a fallen body Eu the succesiiTe equal 

ftre as the odd inte^en." 

Um beifhti from which bodies fall are pro- 

to the aqnares of the timrs of the fall, and 

Ivea are proportional to the velo- 

rs that tbe heights are propurtional 

of the Telodties. That a body may 

iblfl Telocity, ic is requisite that it 

a fonr-fold height, and so on. 

MANUFACTURE OF ALUM. 

• compoand §abstanoe, consisting of the 

anited with tbe sulphnric odd, n 

of an alkali, togetlter with tbe water 

lUsatinn. M. Thenard's onalyais of au 

with potash, giTca the following pro- 

in 1 00 portt : — 

Dry acid »«.... 54.23 

Potash 7.14 

AJomina 12.54 

Water 46.09 

1100. 
all portion of alnm is found in a nsUre 
; ud that mixed with heterogeneous maltera. 
yhoripally obt^ned by various processes from 
minerals called alum ores. The pnrrst of 
'US ores is the sulphuretted cbty of La 
ir Civita Vccchia, from which the article 
A!um tA made. The ore is wtiite, 
bard, whence it is called petra almni. 
1 1 It is found in veins, and is separated from 
«fpclt by bbftbig. Tbe stones are taken to the 
kiAf oven, which is simply a hole dog on a 
j;iioDB of gronnd about five or six feet deep, 
diameter, having a lateral gallery 
with tbe open air, and the bottom 
On tbe bottom are laid faggota, 
th* aluminoua stones are skilfully 
to form a hoUow rault ; between the 
of which the flame and amoke find a 
The ore is considered lo be suihciently 
it has acquired the peculiar swcot as- 
of alum. 

process is that of piling the calcined 
loaf beds npon a sloping floor, upon the 
of whioh is a ditch of water, which ex- 
whole length. From this ditch the beds 
itly sprinkled with water, which, aa it 
them, nmi bark into the reserroir. The 
iJanith begin to crack and full down, and 
days the whole is converted into a 
tread with a reddish efftoroaoeooe. 
next tilled with water and made 
tW prrpared ore is stirred into it by de- 
■ solatioo la obtained of the re<iuiGite 
it is then drawn off in a turbid state into 
whpreiii it is subjected to a very 
by which the superabundant water 
tbe earthy matter is deposited, and the 
eUtar. Being reduced to the point 
in. It is drawn otf into a SMuarc 



wooden Tessel. eight feet high by five feet wide, and 
constructed so as to be taken to pieces readily. In 
this vessel the solntion becomes crystalHxcd in a 
few days. The mother water is then ponred ovt, 
and used in the solution of fresh alum ore. The 
crystals being dried are ready for sole. 

At Soltofsra* a few miles from Naples, is a plain, 
Qt the top of a hill covered with a white soil, which 
exhales sulphureoos vapors, and exhibits, daring 
the night, tlie emission of a pale blue lambent light, 
in which state it boa continued from the age of 
Pliny to the present time. Tbe white, clayey soil 
being constantly penetrated with solphnreons vapors, 
which together with the constant wetting by tbe 
rain and due. the alum is thus produced by nature 
in large quantitiea, but In an impure state. It it 
therefore collected daily, and lixiviated in large 
CBuldroos, and afterwards crystallized in the usual 
manner as Ust described. The Abbe Mazeos pro- 
cured from sIt pounds of the earth of the Soltafara, 
two and a half poandx of cryatala of alnms. 

The most considerable manufactory in Greit 
Britain, is at Uurfleet, near Paisley, on the estate 
of the Earl of Glasgow. The next in magnitude ii 
that of Whitby, an interesting account of which, 
and the processes, was published by Mr. winter, in 
the 2^th volume of Nicholson's JoamaL The 
stratum uf aluminous schistos is of grcst extcnti 
and about twenty-nine miles in width. It is covered 
by s stratum of alluvial soil, sandstone, ironstone, 
shell and clay. If a quantity of the schistus be 
laid in a hesp, and moistened with sea-water, it 
will take fire opootaneously, and continue to bnm 
till tlie whole iatlammable matter is consumed. The 
ore is broken into small pieces and brought to tbe 
furnace or kiln to be calcined. A bed of fuel com- 
posed of brush-wood, upon which the ore is laid 
and piled up in tbe first place to the height of four 
feet, when the fuel is lighted. Fresh portions of 
rock are afterwards added, pouring it on tbe pile 
continually until it reaches the height of from 90 to 
100 feet, with its base nearly 200 feet square, and 
containing, in solid measurement, about 100.000 
yards of ore. One buudred and thirty tons of this 
calcined schist produces, npon an average, one ton 
of alum. Tlie calcined mineral is digested in water 
in large pits, from whence the liquid is drawn into 
cisteroB, and afterwards pumped npon fresh quanti- 
ties of calcined mine. Tbe strong liquor is drawn 
off into settling cisterna, where the sulphate of lime, 
iron, and earth are deposited. In some works tbe 
liquid is boiled to Hid the purification. The liquid 
is next poured into leaden pans, 10 feet long, 4 feet 
9 wide. 2 feet 2 inches deep at one end, and 2 feet 
B at tlie other, for the greater convenience of 
emptying. In these pans the liquor is concentrated 
at a boiling heat, then emptied Again into settling 
cistems, where a quantity of the muriate of potash 
is added, and then allowed to settle again for the 
spare of two hoars, when it is run into coolers to bo 
cryatAllircd. After atuuding four days the mother 
waters are drained off, to be pumped into the pans 
oa the Buccecding day. The crystals of alum are 
then washed in a tub and drained. They are next 
put into a leaden pan with as much water as will 
make a satnratt'd aolution at the boiling point ; — 
when tbia 15 eiTected it is run oH* into caKkt. In ten 
or tifteca days the caska are unhooped, and taken 
asunder; round the sides the alum u foond in Mlid 
cakes, but, in the inner cavity, in large pyramidical 
crystals. This Ust process la called roching. 



^QAU 




100 



MAGAZmE OF SCIENCE. 



POLARIZATION OF UGHT. 

{HctUTtitetJrx/m page S9.} 

AuoNorr cryiUUixed miDerals, there are manypcu- 
Kssing the property of polanxiog the light tnu- 
mittcd through them ; tbu most retutrkablr of which, 
bowerer, ii the toormaline, nhich, from the mis- 
taken importance and vala? that has beco ftttacbed 
to it, we must briefly notice. 

Thlj> loiueral crystallues id long priimt, whoie 
prinittivc form is the uhluBe rhomboid, having the 
mis par&U«l to the axis of thfi priim. It muct be 
rewemberrd, altv, that the nx\% of rrystala ii nut 
like the axil of the earth, a single line within 
the crystal, but a single direcUun tbroagh the 
•filial : for ■upjKuliig this ligurc 4a] rpprctcnt a 

A 




crystal of any kind, the axb of which is in the di- 
rection 'A X. if we divide such o crystal into four, 
along tJicUuesBB and C C, each beparately will 
hiivejiu axis AG, OX. C"B, ond B C, which, 
when united in oneoryBtal.arealLparallel: every line, 
thrn. within the qry^ parAUel to A X, is an axis. 

Now if we cat a crystal of tourmaline of a proper 
kind, parallel to the axis, into thin plates uf u uni- 
form thickness (about one-twentieth of an ioch]. 
and polish each side, it possesses the property of 
polarizing the light transmitted through it in a re- 
markable maimer. This figure reprMcota one of 



theae plates, the lines across which we maynip- 
posc to be parallel to the axis. Now, if wc hold 
such a plate before the eyr, and look at the light of 
the sun or Hame of a candle, or any artiticial light, 
a great portioo will be transmitted tfarotigfa the 
plate which will appear quite transparent, haTing 
only the accidental color of the crystal, which, in 
apecimens nitcd for these experiments. \% generally 
brown or green ; bat the 'light so transmitted will 
be polarized light, and on being analysed by a 
second plate, which may be done by looking through 
both at the same time, we-shnll find that when the 
axes of both pistes coincide, i. e. are parallel to each 
other, the light which has pnised through the first 
will also freely pasa through the second, and they 
will together appear perfectly tranaparcnt ; but 
whan one is turned round, so that the axea of each 
pUt« are at right angles (scrota each other) as rr- 
preaentvd in the neat figure, not a ray of light will 
pass flirough.— they will appear perfecly opsque, 
although we may be looking at the meridian sun. 

Now if we suppose the structure of the erystal to 
be Tcpreiented by a grating, the bars of which ore 
the axis, we may conceive thnt ita action ujwnordi- 
nary light will hr to traniiDiit turh vibrMtUJii* only 
OS are perfurmed in a plane piiallel with the mu, 



and to itop all others. Henre the ligKt t 
through a single plate will be polariaed. l 
exactly the same properties as the light 
by any other meaoa ; aa may be proved 



i» 



sinr it by any ol the neuw wUeb we 
scribing. But let ua anppaae a aeoood 
to be used ; and as it is understood I 
light which makes ita way tiirough the fit 
line, the vibrations are parnllttl to the axia,~iS 
vlbratioiis being stopped when the axia of tba 
or analysing plate Is perpendicular to tbc t 
represented io the above figure, the vili 
which have passed through the first brings 
pendicolar to the aecond, will also now 
by the se-cond plate in such a positioa, 
is turned round, there will be found to 
tions in whioh the polarizrd light 
the anslysing plate, and two posit 
will not pass through, being whoU] 
posUJons being at right angles to 
will be understood by the last figure, 
the first or polaniing jThite, and B'B 
analysing plate, overflapping the ArsC. 

Having thuB briefly coit»idered the phf 
polariKation according to the undulatory 
must now, iu the aame way, notice tbc ex)di 
whlrh this theory also afl'urda of the sph 
tiomena of interference, which, it will 
seen, must necessarily result froiO'l 
law* of vibratory or uodulatory mc 
have consequently been a principd 
lishing the lluygcnian theory, and 
Dated and most ably propounded 
Dr. T. Young. 

Suppose there-are two aets of wi 
on the aorfece of a still pond of water 
points, at certain parts the waves 
half way between each other, ao that km] 
directions there will be a amooth surfa 
each set of waves is produced by pri 
degree of disturbing force, so aa to 
equal and alike in every raapect, aad 
of one set rjiartly half a wave io advance 
wave of the other ; while, at the 
otiier directions tin waves coincide an^ 
elevations or vibrations of double extent T 
intermediate spsces, intermediate effecla i 
coarse, be produced. 

The sane laws of interference exiat 
which, it is well known, consists in th 
or vibrations of the particlca of air actii 
aensonum of the ear, and producing i 
culled sound ; but the consideratiOQ i 
nomena would here occupy too aauch 
not necfasary to our subject. Tbe 
acoustics fumisbea experimentaldemoi 
two sets of andulatioDs ot air pmdi 
may be made to interfere and destroy 
(or, m other words, two sooiiris may be 
tcrfcro aad produce tilcnoe) j nod ■ 



MAGAZINE OF SCIENCE. 



101 



^er produce the nme effecU, we m«y, 
[7. expect, if light consUu in tlie uadu- 
n tlastic medtuta, that two U)(liU may 
)« to interfere and ^roUoce dapknesa. — 
I ta-anck a thing may appear to be, the 
Viiatcace of aach a phenomenon in light 
I by Grimaldi, aa long liacc aa 1G65. — 
Dr. Young that Hcience is indebted for 
i prored — and thti Freanat and Arago 
roiUirmrd beyond all question or dlapute 
|ia d&rk baadi and colored IriQges afe 
f the interference of light. 




It ii quite irapoauble, Id a paper like thif, to do 
juitioe to thia great and important branch of the 
theory ; and aa we arc now conaldering only the 
phenomena of colora in polarized light, the ex|dana- 
tion already given of the interference of the undn- 
lationa in water, will enable ua to anderstand how 
the splendid colora are produced, according to the 
lawfi of interference, by the action of doubly re- 
fracting bodies upon polarized light. 

For thia purpoae let D, in the annexed figure, by 
the polarized ray incident perpendicularly upon any 
double -reTracling cryatal ; the beat for this parpOM 



K 



bin film of aelenite E, vhiob U rrpn- 
nrayi, and should be about the fortieth 
f an in£h in thii^nesa, and may easily be 
kiufe from a large piece of the mineral ; 
lite tntnsparent, aud brr^k most readily 

B sired form. If such a film is placed in 
liolder of the polarizmg apparatus at- 
9be hydro-oxygcD microscope in certain 
rhich will hereafter be eiplained,) an 
fl film will be projected by refraction 
analysing bundle FI of glass, upon a 
IB duvction L \ but instead of being 
dorleaa, as the cTyital appeara in ordi. 
its wbote figure wilt be covered with the 
t colors, and, if of a perfectly unifi}rm 
iuroaghout, it will be of a |>erfcctly uni. 
throughout ; but if of different thick- 
rill he of dtSerent colors, varying and 
ith erery degree of thickness, no matter 
or imperceptible by any other means of 
, or the most powerful microscopic ex- 
Polarised light exhibits a different tint 
kriatioo, bat all of the most bnlliant de- 
At the aame time a second imsge will 
! fhim the aoalysing bundle Fl, and can 
ftpon a second screen in the direction 
• of which will be equally brilliaat, but 
Ury to the other reflected rays, 
pposing we hare a film of a uniform 
^Ttng in the refracted image L a red 
the reflected image S will be green.^ 
hing will take place if the film is of dif- 
oesaes giving different colora, aa every 
complimentary color, and those of one 
ftlwayi be complementary to the other ; 
blended together or superposed, will 
Ught. 




film b made to torn round in such a 
the jiotots or angles may follow ench 
alternately uppermost, the polarizing 

parts of die apparatus rcmaioiDg ala- 



'<^J=^ 



tionary, tbere will be found certain positions ia 
which the film will have no action upon the poU- 
rized light D passing through It : these positions 
are when either of the cross lines, A B or C D, ia 
parallel to the plane in which the vibrations of the 
polarized ray are supposed to take place. 

In such positiona the tight passes through the 
crystal without anffering any change. This ia 
proved by causing tlie analyaiog bundle of glaaa 
H H to revolve, the aelenite remaining stationary ;~> 
when it will be seen that at each quarter ot a cirdtt 
the tight will be alternately reflected, and trans- 
mitted or refracted in just the same way that it ia 
when the aelenite ia removed; as we have previously 
noticed in explaining the action of the analysing 
bundle of glass. 

As the Sim is turned round, it will be alternately 
in four different positions. Hence these lines in the 
sclenite A B and C D are called neutral axis i be- 
raase, in the pDattinnsdeacribed, it exerts no acdon 
upon the light passing through it ; white, ia the in- 
termediate positions, it does alter the character of 
the light, and in which all the splendid phenomena of 
colors are aeeo. 

Let OB now sqppoae the film to be turned from 
its first position : aa soon as it begins to move, the 
two images seen at Land S will b^n to exhibit the 
moat brilliant colors, which will increase in bright- 
ness until the film reaches one quarter round, where 
they will t>eat their maximum or greatest brilliancy; 
and when L ts red, S will be green ; or if L is blue, 
S will be orange, &c. &c. Bat, as the film tnrna, 
the colors wilt fade ; till, having reached the next 
quarter, where they will be at their miDimnm or 
nothing, there being no actiou exerted by the film 
in anch a position ; but, as soon as it has paaaed by. 
the colora begin again to return, till it haa reached 
the fourth position, where they are again at their 
nuxiinum. The same thing will occur at every 
qaarter of a circle ; and, in continuing the rrvolB* 
tion of the film, we ahali find four positions in 
which the film eierts a peculiar action upon the 
polarized light passing through it. 

Now, to understand how these colon are pro- 
duced by the interference of the undulatioos of the 
tight, let the film I^ be placet! in the polarizing ap- 
paratus, in such a position that the two neutral 
axes A B and C D are inclined 4^" on each side uf 



loa 



MAGAZINE OF SCIENCE. 



the plane of iribntions or the polariced light, or 
perpendicular, aod of such a thlckuekS u to gift a 
red itna([e at L, and a green one at S. If the 
unaJyslng bundle H H ta now removed, the image 
wiU atiU tw leen at L, but pmfcctly clear, Mrt bflTing 
the least appearuice of color. It ii erideut, then, 
that the analysinp part of the apparatoa la equally 
necessary fur the pruducCiun uf colors. Let oa, 
however, first notice wh«t the action of the selcnite 
E is in such a position upon the polarized light 
puaing through it. Nov, being a doubly refract- 
ing crptal, whrtn its neutral axes are thus inclined, 
the light passing through it will be doubly refracted) 
and, olthoagb not perceptible to the rye by ordi- 
nary observation from the tatreme mioulencsa of 
the sepsrstion in so tbio s film, yet, from this pro- 
pvrtT which tre kuuw it possesses, it is nevBrihelesa 
divided into two equal portions or sets of waves, 
the vibrations of one being parallel to the neutral 
uia A B, and the vibmtiona of the other parallel 
to the axis CD, and, consequently, both inclined 4b'^ 
to the perpeodicuUr, as shown at O X : O we may 
call the ordinary ray, and X tbe extraordinary ray. 

ilut iu the pisaage of the two ruys through the 
crystal, they have traversed it in different directions, 
with different velocities ; one of these sets of waves 
will, therefore, on emergency, be retarded and lie 
behind the other; but, being polarixed in different 
places, cannot interfere. To cause them to inter- 
fere and exhibit the phenomena of colors, their 
planes of polarisation or vibration must be made to 
coincide. For this purpose, let the analysing bun- 
dle of glass bt! placed as at H H, in which position 
tbe vibrations of both the ordinary and extraordi- 
nary rsys O and X are each inclined 45° to a plane 
perpendicular to the pUne of reflection, and, con- 
aequentty, that vibrations in a beam of ordinary 
light, inclined at angles between the perpendicular 
■nd borttontal planes, are divided into two portions, 
one of which is reflected, and the other transmitted 
or reft«cted ; so now again, the same effect will, of 
coarse, take place, and the vibrations or waves of 
the reflected half S of the ordinary ray O, will be in 
a plane parallel to the plaoe of reflection of H H, 
and the waves of the reflected half L of the extra- 
ordinary ray X, will also be in tbe same plane- 
Here, tnen, we have two sets of waves onglnatiDg 
f^om the same vibrations in the polarised rsy D 
brought into the same plane, and, consequently, 
DOW pOBScising all tbe conditions necessary for in- 
terfering with each other ; and tbe same aUo in the 
two transmitted portions. 

Tbe colors of the images at L and S produced by 
this interference will depend upon the interval of 
retardation of one of the rays within the medium E, 
which, of course, will vary with its thickncM. When 
this thickness is such as to cause the interval of re- 
tardation to amount to half a wave in the reflected 
rays K and L, they will interfere half way between 
each other, and ao far destroy each other as co pro- 
duce in the image at L the black uf the first order, 
•een by reflection, in Newton's " Table of Colors ;" 
while, in the transmitted rays, the waves being In 
opposite phases of vibration, will coincide and ex- 
hibit in the iaiage S, the white of the same order 
aeen by transmission. When the thickness is snch 
as to cause an interference in iotcrmediAte degroes, 
Intermediate effects or colors wilt be produced ; — 
consequently, when there is exhibited at L any one 
of tbe coh>ri ia Newton's Table seen by reflectiott, 
tbe image at S will always exhibit the comply- 
nrntxry color been by transuiiBaioo, tbe waves of one 



being always in opposite phases of ribratian to tha 
wQvea of the other. 

And we iboll find, as the film of selemte is made 
to revolve, tbe bundle H li remaining itatiooaryt 
that it will produce one color only at L, appearing 
and difiappearing alternately as it passes Uirougk 
them, and the same with the complcmcotsry rolor 
at S, But if tlie flhn is fixed in any o( tius posi- 
tions in which it gives the brightest color, and thfi 
buudle of glasi H H, made to revolve, two colora 
will be seen both at L and S, which change altor* 
nately at each quarter of a circle ; thos, wbok H H 
is in one position, and the image at L is red, aad 8 
green ; when 11 H has turned round 90°, L vriU be 
green, and S red; at 180° L will be again rtd^ 
and S green, and at 2^ff L will be again green, and 
8 red. 

These, and aU the splendid phenomena of colon 
in polarised light, will readily be seen to be simple 
conaeqnenoea resulting from transversal vibratiooa ; 
for, when a single wave or vibration in any one 
plane, as at D, is divided or resolved into two at 
right angles to each other, one will, of oeceaslty, be 
half a wave behind the other, the two being tbe op* 
posite halves of the same in D ; and as each of these, 
O and X, is again divided or resolved into two 
otiiers, there will be four waves or vibrations pro- 
duced from tbe original one. Two of them in one 
plane must, of necessity, coincide or consplrei 
while tbe two in the otJier plane are opposed. 

Tbe colors produced by the interference in one 
plane have been shown by Fresnel to correapond to 
the amoant of retardation within the cryatal, and 
tbat in tbe other plane to be due to the same amoanC 
of retardation augmented or diminl.sh^d hy b&lf a 
wave, and, couscqucntly, complementary to the 
former. 

In this brief notice of polarixed Jight, tke expla- 
nation is confined to the phenomena exhibited by 
a. single plate or film of srlenito ; tbe colon of 
which wc have seen, vary with its thickoess. M'ilh 
this single crystal, then, numerous splendid and 
beautiful effects mny be produced, simply by pro- 
curing different thici^nesses for giving difl't'reDC 
colors, and so arranging them upon a plale of glass 
as to represent different subjects ; such as painted 
windows, bunches of flowers, fmitSy and other 
figures. These, in ordinary light, will be pet/ArUy 
transparent; but, when viewed in polarized light* 
will exhibit the most gorgeous coloring, and 
made to undergo the most extraordinary c 
by simply causing the analysing part uf the 
ratUB to revolve. If single plates of selcnite, 
any doubly refracting crystal of considerable thick- 
Dees, be ground away on one edge so u to give then 
a wedge shape, thc-y will preaent bnuds or fringes 
conipused of all the colors of Newton's Table, aris- 
ing from tbe various thicknesses whii-h such a shape 
possesses, or by grinding a concavity in a similar 
plate, a number of conctntric rings are produced* 
Thus it will be seen a variety of forms may 
given, prodacing a variety of effects; these, 
thousand more, such as tbe small cryetdb 
duced by evaporating sin^ drops of aol 
acetate of tine, chlorate of potUi, eolphato 
oxalic acid, oxalate of ammonia, ami natty 
may be exhibited by means of the polarixiag app**" 
ratus adapted to the hydro-oxygen microeeope.^ 
This apparatus will be described in tbe next paper 
on tbe sabject. 

fToheeonlinueiSJ 






MAGAZINE OP SCIENCE. 



103 




ESSENTIAL OR VOLATILE OILS. 

IK t-oUcUe oili ocoar In every part of odoriferous 
Ats, w1iu«e MromA they diffuse hj their exhaU- 
R ; but ia differeut organs ot different ip«cie«. 
rrtala plint«, such as ttijme and the icented 
ttel«. in geoer*! contain ToUtila oil in ill their 
rti I but others oontaln it on\j in the blossoois, 
l i wdt, tha leaveit the root, or tlie bark. It 
atJuiM bappena that different parti of the same 
Bit dootoio different oiU ; the oran^, forfiampte, 
thm different oilt, one of which residrs 
another in the leaver, and a third in 
lidvmis of the fmit. Tlie quantity of 
only with the apecies, but alao in the 
tm ffaflt, irilfa the toil, and cspeciaUjr the climate ; 
m in bol countries it t> generated moat profusely. 
Mnrml pbatSi the roUtile oil is contained in pe- 
)hK Ofdara of veasda, which confine it so closely 
kl It doe* not escape in the drying, nor i* disjii- 
loll by keeping tbe plants for many years. In 
and particularly in flowers, it is 
mally npon their surface, and flies off 
of its formation. 

ore usiiiilly obtained by distillation, 
the plant is introduced into a still, 
upon it. and heat bein^f applied, the 
lilisfid by the aid of the watery vapor, at 
toreof 212^, though when alone it would 
obably not distil over unless the heat were 100^ 
M9b Most of the essential oils employed in medi- 
M«ad perfumery ore cxtractod by distillation from 
M pUftts ; only a few, such as those of the rose 
4 «nage flower, are obtained from fresh or anc- 
llest Mited plontj. When the mingled f apors of 
oil and water are condensed into the liquid state, 
jf iW refrigerator of the still, the oil separates, and 
Ikir AoaU un the surface or sinka to the bottom 
fibs water. Some oils of a less volatile nature re- 
lira* hifber beat than 212^ to raise them in vapor, 
■d moat be dislodged by adding common s^lt to 
te wUtTt whereby the beat being augmented by 
y, tbey re*dily come over. If in such distilln- 
ioos tiw marb water be added no oil will be ob- 
riaed, because it is partially soluble in water ; and 
bw mrrely an aromatic water is produced. If on 
Uolber hand loo lUtlc water be used, the plant 
taybappen to adhere to the bottom of the itill, 
lift partially charred, and thus impart sncmpyreu. 
MOe odour to the product. But as the qaulity of 
Mv dtstiiled depends leas upon the i|uaiitity em- 
lloywi. than upon that of the surface rxpui^ed to tttc 
■^ it is obvious that by giviog a suitable form to 
butfUt, wc may get rid of every incouTenicuci'. 
^Hl the narrower and taller the alembic ia, vrtthin 
Hb liniita, tbe greater will be tlie proportion of 
BSUitiT« to thnt of the aromatic water, from like 
|i«peniODS of oqaeous and Tegccable matter em- 
flayed. iioBtc place tbe plants in baskets, and 
ffRld Iheae immediately over the bottom of tbe 
■ader tbe water, or above its surface in the 
taaai. Hot the best mode is to stuff an upright 
nttndcr fall of the planl«. and to drive down through 
Maa, atcmm of any desired force; its tension and 
hbpaiatsrr being further regulntcd by tbe size of 
hi onllflt ortAce leading to tbe condenser. The 
■HoJtr abooUl be mnde uf strong <!opper, tinned 
■Me, Oftd moased in the worst conducting species 
If wood, anch .is soft deal or sycamore. 

Tbe dtattllation is to be continued as long as the 
Vtl#r eomes orer of a milky appearance. Certain 
||mU yvsld so little oil by tbe ordinary procesaes. 



DOtwithfltandiDg every care, that nothing bnt a dis- 
tilled water is obtained, la this case, the same 
water most be pnorcd upon a fresh quantity of the 
pUuta in the still ; which being drawn over, is 
again to be poured upon fresh plants ; snd thus 
repeatedly, till a certain dose of oil be separated. 
This beioi; taken off, the saturated water i* reaerved 
fur a like diBtilladon. 

Tbe refrigeratory veasel is ustwlly a worm or aer- 
peotine plunged in a tub of water, whose tempera- 
ture should be generally cold ; bnt for distilling tbe 
oils of aniie-serd, fennel, &c., which become con- 
crete at low temperaturea, the water ahoold not b« 
cooler than 45'' Fahr. 

The liquid product la commonly made to ma at 
the worm end into a Teasel called an Italiaa or Flo- 
rentine receiver, which is ■ conical matnus, standing 
on its base, with a pipe riung out of tbe side close 
to tbe bottom, and recurved a Uttle above the mid- 
dle of the flaak, like tbe spout of a coffee-pot. The 
water and the oil collected in this vessel soon aapa- 
rate f^m each other, according to their mpective 
apeciflc gravities ; the one floating above the other. 
I f the water be the denser, it occupies tbe under por- 
tion of tbe vessel, and continually overflows by llic 
spout in communicatioo with the bottom, while the 
hghter oil is left. When tbe oil is the heavier of 
the two, the receiver should be a large inverted cone, 
with a stopcock at ita apex to run off the oil from 
the water when the separation baa been completed 
by repoae. A funnel, having a glaai stopcock at- 
tacbed to its narrow stem, ia tbe moat convenient 
apparatus for freeiog tbe oil finally from any ad- 
hering particles of water. A cotton wick dipped in 
the oil may also serve tbe same purpose by its capil- 
lary action. The less the oil is trsnuvased the bet- 
ter, as a portion of it is lost at every traiihfer. It 
may occasionally be useful to cool ttu; distilled 
water by surrounding it with Ice, be<tause it tbua 
parte with more of the oil with which it is impreg- 
nated. 

There are a few easeotial oils which may b« ob- 
tained by expression, from the substances which 
eotitnin tbrm ; such aa the oila of lemons and ber- 
gamut, found in the pellicle of tbe ripe fruits of the 
eitruM anrantium and medico .- or the orange and 
the citron. The oil comes out in this cose with the 
juice of the peel, and coUecta upon its surface. 

For collecting the oila of odoriferous flowera 
which have no peculiar organs for imprisoaiogtbemf 
and therefore speedily let them exhale, auch a* 
violets, jnfmine, tuberoie, and hyacinth, another 
process must be ivsorted to. Altemste layera are 
formed of tbe fmli flowera, and thin cotton fleece 
or woollen cloth -wadding, previously soaked in a 
pare and inodorous fat oil. Whenever the flowera 
Imve given out all their volatile oil to the flxetl 
oil npon tbe fibrous matter, they are re-placed 
by fresh flowera in succession, till the fiit oil 
has become saturated with the odorous purticleH. 
The cotton or wool wadding being next submitted 
to distilUtion along with water, givea up the vola- 
tile oil. Perfumers aloue ote these oils ; tbey cm- 
ploy them either miied as above, or dissolve tliem 
out by means of alcohol. In order to extract tbe 
oils of certain flowers, as for instance of white lUiet , 
iiiTuaion in a fat oil b sufficient. 

Essential oils differ much from each other ia 
their physical properties. Most of them are yellow, 
others colorless, red, or brown ; some again are 
green, and a few are blue. They have a powerful 
amell, more or leaa agreeable, which immediately 



104 



MAGAZINE OF SCIENCE. 



after tfadr diftiUation ii occuionaUy a little rank, 
but beeotnci lesa ao hj kiteping. The odour ia aeldom 
«a pleaaant aa that of the rccrat plank. Tbeir taste 
if aerid, irritating, and beating, or merely aromatic, 
when tbey are largely diluted with water or other 
oubstancea, Tliey are not gmMj to the toncb, bite 
the Ht oila, bat, on the contrary, make the skin feci 
rotii^h. They are almost aU lighter than water, 
only a very few faUinK to the bottom of thia liquid ; 
tbeir ipeeific gravity Wes between 0'H47 and 1*096; 
the firat aamber denoting the denaity of oil of citron, 
and the aecond thst of oil of nnafraa. Although 
styled ToUtilo oiIji. the teodoo of their vapor, aa 
well ai ita speciiic heat, ia much lean than that of 
water. The boiling point differa in different kindH^ 
but H ii uiually about 316" or 320'^ Fabr. Tbeir 
Tapon aoRietimei render reddened litmus paprr 
blue, althoDgb they contain no ammonia. When 
distilled by tbemaelves, ttie volatile oils are par. 
tially decomposed ; and the gaacooa prodacta of the 
portion decoaipo*ed always carry off a little of the 
oil. When they are mixed with clay or Mod, and 
caposed Co a distilling beat, they are, in a great 
neasare, decomposed ; or when they are passed in 
vapor through a red-bot tabe, combustible gases 
■re obtsioed. and a brilliant porous charcoal ia de- 
posited in the tube. On the other hand, they distil 
nadiXj with water, becaoae the aqneoua vapor, 
formed at the sorfaoe of the boiling Raid, carriea 
along with it the rapor of the oil prodnred in virtne 
of the tention which it poMCsses at the 212ih deg. 
Fahr. In tlie open air, the volatile oils born with 
a shining flame, which deposits a great deal of soot. 
The congealing point of the essential oila varies 
greatly ; some do not solidify till cooled below 32", 
others at this point, and some arc concrete at the 
ordinary temperature of the atmosphere. Tbey 
comport themselves in this respect like the fat oils ; 
and they probably consist, like them, of two differ- 
ent oili, « solid and a fluid ; to which the nsmea 
Hearopt^ and ckoptme, or stearessence and oLei- 
easeoce, may be given. These may be aeparated 
from each other by compreuing the cooled concrete 
oil between the folds of porous paper ; the atcar- 
essence remains as a aofid upon the paper ; the 
cleieaaence penetratea the paper, and may be re- 
covered by distilling it along with watrr. 

When exposed to the air, the volatile oils change 
tbeir color, become darker, and gradaally absorb 
oxygen. Tbia absorption commences whenever tbey 
are extracted from the plant containing them ; it is 
at first considerable, and diminisbea in rapidity ns 
It goes on. Light contributes powerfully to thia 
action, during which the oil disengages a little car- 
bonic acid, but mudi leas than the oxygen absorbed ; 
no water is formed, 'ilie oil turns gradually thicker, 
looe»itsnneIlt«nd is transformed into a resin, which 
beoomas ffventually hard. De Smssure found that 
oil of lavender, recently distilled, had absorbed In 
foor winter months, and at a temperatare below Si4'* 
F., 52 bmes its volume of oxygen, and had disen- 
gaged twica its volume of carbonic add gases ; nor 
was it yet completely saturated with oxygen. The 
atearesaence of anise-seed oil ahaorbedat its liquefy- 
ing temperatare, in the space of two years, 1&6 
times ita volume of oxygen gas, and disengaged 26 
times ita volume of cnrbonic acid gas. Ao oil which 
has begun to eji{ierieuce such an oxidizemeut )« 
eompoeed of a resin dissolved in the unaltered oil ; 
■nd the oil may be separated by distilling the solu- 



tion alor^ with water. To preserve oils In an ii» 
changed state, they must be put in phials, filled U 
the top, closed with groond glass stopples, an^ 
placed in the dark. 

Volatile oils are little soluble In water, yet 
so as to impart to it by agitation their c 
istic smell and taste. 'Die water which distila witll 
any oil is in general a satorated solution of it, to 
as such is used In medicine under the name of di« 
atilled water. It often contains other volatile sub- 
stanoea oontaiued in the plants, and hence ia apt lo 
putrefy and acquire a nauseous smell when kepi fai 
perfeoUy oorked bottles \ but In reasela purtiallf 
open, these parta exhale, and the water 
sweet. The waters, however, which are made hf 
agitating volatile oil with simple distilled wster, ar« 
not apt to spoil by keeping in welUcorked bottles. 

l^e volatile oils are soluble in alcohol, and tbfl 
more so the stronger the spirit is. Some 
oils, devoid of oxygen, such as the oils of tarpentiM 
and citron, are very sparingly soluble in dilate 
aloobof; while the oils of lavender, pepper, &c. 
considerably so. De Saaaanre has inferred fro« 
bis experimeuts that the volatile oils are the enora 
soluble in alcohol, the more oxygen they coBtain.— 
Such oembinations form the odorifmnis apiritl 
which the ))erfumers incorrectly call watera, 
lavender xgater, eau de Coiopte, eav de jantun. 4-f. 
They become turbid by admixture of watrr, whtcb 
seizM the alcohol, and separates the vobtilB (rila 
Ether also dissolves all the easential oila. 

These oils combine with several vegetable acids* 
such as the acetic, the oxalic, die succinic, the fat 
acids (stearic, margaric, oleic,) the camphoric, and 
suberic. 

With the exception of the oil of cloves, the vola- 
tile oils do not combine with the salifiiblc buses -* 
Tbey have been partially combined with ranstifi 
alkali, as in the case of Starkey's soap. This li 
prepared by triturating reoenlly. fused caustic mm1« 
in a mortar, with a little oil of turpentine, addrd 
drop by drop, till the mixture has acquired the nm* 
sistrnrc of soap. The compound is to be dissolved 
in sptrita of wine, filtered, and distilled. Wbit 
mains after the spirit is drawn off, consists of 
combined with a resin formed in the oil during thi 
act of tritnration. 

The volatile oils In grneral abaorb six or rigfcC 
times their bulk of ammooiiical gas ; but that «i 
lavender absorbs 47 times. 

The esAentiol nils dissolve all the fat oila, tiM 
resins, and the animal hU. 

In commerce these oils are of^en adultrrated wtKb 
fat oils, resins, or balsam of captri diasolred i 
volatile oil. This fraud may be delecled by pattio 
a drop of the oil on paper, and exposing it to heat* 
A pure essential oU evaporates without leaving snf 
re«daam, whilst au oil mixed with any of the abor^ 
subslannrs leaves a translucent stain upon the psprr. 
If fat oil be pre«ont, it will remain undisFolved, om 
mixing the adutlcrated essential oil with tbrice iti 
volume of spirit of wine of specific gravity 0*840.— 
Resinous matter mixed with volatile oil ia easily 
detected, being left in the alembic after dittillation. 
Oil diluted with spirit of wine, forms ■ milky emnl 
sion on the addition of water ; the alcoholic part t 
absorbed by the water, and the oil aftcrwaril!i found 
on the surface, in a graduated glosa tube will show 
by its qaantity the amount of the adultervtioa. 

f To be continued. J 



L/onDOM ■— Pruttd by U. faAMCts, 6. WtiUt Hone L^ajis, Mtla EwL— I'ubluii«u ity W. fiatttAix. tl, Psisruoaifr Mo*. 



THE 



AGAZINE OF SCIENCE, 



^nif StDooI of ^m* 



SATimDAY. JULY 3. IMI. 



[IK 




Fig, 1. 




HYDRAULIC ENGINES. 



5^* a. 




UYDIUUUC ENGINES. 
(Betuawi fn» potg* % I 

Archimedra't Screw. — It rrprc«mtr<l and tlc- 
■crilied us IoHowp: — A I* ii Uiillow [liitc, coU«l 
arotuid a ryliiidriciil mi* ; wbi<!U hxU U incline*! itt 
ao iui£lt' with the Kroviml, nnd suppnrteU at enrh md 
upon pi\oU(, the upper pivot bcini; furnished wirli 
handle. WliPTi thin in turned i-ound. the lower 
end of the pipe dips into thr wnicr in the well biilow, 
aiid turniiipr upwards directly scooj'* up some of tlie 
wolcr. M hen Uk* end point? up, the jujrt B will 
buu(;uic Inwfr thnn it, therefore the wuter will full to 
B. Another hiJf turn of lii'- hiuidlc brings C to 
Ihe loweal point, »nd thi* lirst wnter will oerupy 
tbftt pfirt of tie !ul>c ; id the wme time more wjiter 
wiU be scooped up at the end. Ill n numbpr of 
turns uf Uip liandlr, cqu.il tn that of (he roils of the 
tube, the lii>t water >« ill rtac)i, ;md finw out at the 
top ; Bhd from that time a. flow will lake plai-c »t 
every revolutioa of llic rocctii:ic. 



itlut np^ninff nptmrd". 




Barkrr'n Ctmtr^wyaJ Miti. — TbU raiiinblo inrtru- 
tneiit di^rivCB its pow.M" from the force ac<jnired from 
■ stream of writer ni^iinic fn>in two hoK->, *o plnced 
uciu- the i-adi Litilu ..rn.rt of « moTeat>l- f-pindbai 
to throw Ihr water on em-li i-idp, and thereby to oc- 
coftioii a couolrr j«ctiou iigninsL the anus, propelling 
tbem, nnd svhnu'vcr may he ntfnched to them in a 
contrary direction. Suppose A in the cut to repre- 
8<<nt D fiiniit'l conurctid wiUi ttie hollow kpindle (■, 
thiA repts ut th.- Injttnm on a pi\ol C, and hear* a 
shaft above, wbiih i» eoiuiected with one of the mill- 
utone* E. n>e hollow piirt (1 is terminiitrd by the 
two hollow arms H B, whirji orniR hflTO ludes. ft* re- 
prccenled. A tt.'wuu of wuter tlowing into A will 
fidl down into G, and fill the arms B 13. at length 
ru*<hin? out of the holes. The nir will offer such a 
reai-^liiiioc to the iaimUtg of the wnter, that the armst 
toi^eihcr with thf* oibcr moveable ports, wiUrevolre 
rBpidly. — at f Jig. \. 

Ducket KHffin*. — A aubfltitnte for an over-«hot 
water wheel, and fur superior where ihe fall of water 
is enntiderable, and the bupply limited. An endlesf 
chftiii, carrying a series of burk(-t.s, is made to re- 
volve ou two wheels, A B, called ray-xohecU. The 
water flowa into the highest bucket, and when it de- 
it/^ct\iU the nett bucket takes Itt^ place and it, Uke«'l^ 
filled, And thuf every bucket on one side is filled, 
wliile those on the oppt^^itc side, being inverted, are 
empty. The chnin of biii^keLs i? tbert£fore conalnnlly 
carrital round by the wcipbt of the water. — Setfg. 2. 

LVntt'ifti^at Vumjf. — A machine dependent upon 
cctiirifugul force. «^'iabincd with the pressure of the 
atmosphere. It coni-itts of one, two, or more amia, 
erect i'i*Iow, and branching opt above, joined to a 
vrrtical axle. Near the upper citreraity of cnch 
ami 1* a fla»^k volve openiug upwrirds, while near 
the lK>itoui of the vertical tube, or the bottom of 
«acb , {\f tbca« are more than one,) 12 a siniibir valve, 



Wftt^r hrin? poured tula 
r >1 moiion beiity 

'.rr in the ajtUn 
'.- tbr 

t" . ■. .. .... ..!...../ . ' ■:_ . ..' . ..live 

u a wrlUniade pump. — ^ee_Tl(;. i, 

C^ain FJtmp, — An instrument which act* upon « 
principle contrary to that of tlic bucket cni^nc : h 
may be either fomted of bti<rketAintlte!wmr nmnner. 
or what i» more simple nnd com 'j 1 of 

budtets, there ore set at certain m ' >rr- 

vali on on endlcsf ctialn a (<en-" ■■* -nd 

plates of metitl, which nertrly lite 

tabes in which they work. I la 

motion, pupposinj; the bottom ot' n fhr 

uater of R well, eueh pi:iton will ioi it 

certain (jnanlilT of water, and bear thii Wdii 10 tli* 
top, where it overflows into a ciatern preparrd i* 
receive it. — Serjig. \. 

Ecvmlrie Pump. — Conisifita of a hollow dram 
cylinder of met;tl, JJ D ; iu the interior of wbirh, a 
solid eylindrr, D, of (he frtmv Irnieitb, bat of ItA A* 
ameter, it made to revolve in water-tight axw. 
The inner cylinder being plai-ed «o nuicb out of iJic 
centre of D D, that in it? revolution, one side of if 
toihbrs the side of B. T!ie aurfni-c of the inorf 
c>hnder!s also faniiAhL-d with four clrculor Ha^ 
C C C C. Two rodR of metnl slide tlmiiigb U. fo 
to o]Hrn the Tulves on our fide, nbfn the oppovOa 
valves close by pressini; ajainrt the case of D D. 
The water is .'Upplied from the well, through A; it 
i^ then scnopeil up by the opeitiug valve, and con 
veyed by that vatfVe to the top, where, oi the v«lw 
dopes, the water is sfjuet-r.cd up into llie [npe E. 




THE LAW OF PATENTS.' 
Wc have been so often urged to pivea pBper (*r twQ 
on the pst<*nt laws, and brlieve It to be a iubjcel to 
fraught with interest to .-lUbelonpng to an inTtnllte 
and manufiicturiug country like thi», that it ii with 
the very greatcat plesfure we iDtrodnca a iubjcd ao 
generally interesting. 

Tatent, in l»w, jk the exclusiTe rij;ht of usineand 
vending a certain composition or combioatioD of 
matter, rb a medicine or a mnehinc. Thi- 
not drrixed from the Ian- of nature, a« ' 
field of inventions and improvements is uj . 
men, and one cannot monopolixe a part of it hy 
prior discoveries. By the common l.iw of Engbind, 
monopolieB were dc<*lared to be grnrni!ly void, and 
patents fur new inventions, being a ^pri'ire of mo* 
nopolirs, would, according to Ibis <'. 
by thit law. But they teem to for 
to thin rule; for it waJt brl'.) ' 
confer on the inventor of any 
art the power of uting it for l i _.. 



rito 



MAGAZINE OF SCIENCE. 



Cho law of ptttroUi, n H no<v tCnmU in England, 







■■ ?1 Jan. 1, c. lii, nml in tl»c 
K-'it cin <riitni« I-V>. 21, 
>. In IVuni;*, mail WOO, 
(ibligt'fi to keep tli'jjr tlU- 
10 <i*ruro t»» tiiem»<!lvM a 
'>t'tti«m. In Ha CMtiy itc* 
■ iiioii, ft Uw WM5 p«sfted in 
rortnrJ ou the UiaU a( the 
••nob kwof Jan. 7. 18t0. 
' i^r new iuveuiiaii, in 
<• , it tUe pru|irrt]r uf 
, .ittj ftro now» [48 Ibcy 
•I Juines I, gronted by tbe 
<rc wiilv uitl Ity lUo »ecre- 
•1 or tUe L'nilvd i»LaUta uf 
I lie president. 
' '' . ^In jseiicrtil, uny inTcntiun 
I a.rt, uifti^hiue, uunuiucture, or 
:cr nol knowu or lucd befure, ur 
il tinpriivemcnt in any art| nin- 
(ure. or cumpoiiltioTi of luatlur. 
must be new. lii Knglnnd, « munu* 
'►rottsht (ri«u tlie kiugiUmii friiin be- 
rf, v^ nllowed by the 
: suture nllows a pa> 
witiuii ibis ruiini. 
1 Slatir<) of Ainericu, 
. ..riginally diEniTercU 
• bad Uiru in utit?, or bud been 
I'ublic work niitrrior to (be Bup> 
iy by tbe piiteiitee, or if he baa ftur- 
lilnined » pnlr-nt for tbe diKovery of 
<n, H>c pntcnt is voM. In France, by 
n. 7t 1810, whucTcr introduces into 

, . I... , Jj.^ovcry sball enjoy tbe 

■J were the inventor. In 

f sn in7entio)i is entitled 

r be be tbe inventor or not. The 

nutut be vendible, in L-ontradi&- 

ing that ifl Itarued by pntctice. 

■I hf maferiai attd us^iil : thus 

I'lrcrtol fnrt^iiotber is iiuuf- 

il ; at of bmsfi hoops tu n 

.1 onta. So there ciiiinct be 

: iu one piece nhat before was 

if one trlemeotary thing be sub- 

iut anollicr, sk if Ihnt be done by a tube 

4ft hrfore done by a ring, a pileut for the 

■ would hej^uud. It must not be burt- 

ii'jr getiL-rally inconvrnient, nor mis- 

: ioimurol, bj uii invention to poison 

'i> promote dt-bauchtrry. Patents for 

- Mtc Tslid, ai for an improved steam- 

^f the improTcmeoti cannot be used 

nginc whirh is protected by a patent, 

t the expiration uf the patent. But a 

iv be taken unt fur the improvement 

It of old QiateiiikU, by which 

i-d, may be tbe subject 

. .. i.M^ it ni«y cuustKt either in 

11 of a new iiriiilf, or in mnlnn^ an 

I hriUix uianu'ir, iu a ttbortcr tin.c. 

■•r rate. A I'litriit may be ubl'iiitcd 

•r pn>ce«a by which wiDelhing ucw ur 

when it ii connected with cor- 

Tiid i* carried into effect by tuii- 

Mic (MAt- of W*tt*a atciun-cngine. 

■'I to be a mt'lliotl of Usaening 

I fuel th a "'• iii.-.ri,.i,>,.. Sn u 

. whfn It Ki' Minmnity 

If, uitd bvti JBce, or 



m 



roupoaiid artiele. ia u subject uf a patent, as m«dU 
ciriea, Kr, tint a pntent fur n mere turio«ity ia 
void. If the niJi'infarturn in il* ntw slute merrly 
answers M ni-ll iH bcfoii'. the dltrrotion is not ihe 
subject of a |ijiLvut ; nor is a rncre phUtHoj>bicAl 
abbtrsec princijite, nur the Bpi>licatinu or {iractice 
of tt printMplr. tlic titjbjt'ct of a patriit. No pntfut 
can be ubtuined for ihr t-xpatu^ive opcruttou \f( stcmn ; 
bnt only fur a new uiode ur apjilicutiun of maublncry 
in eiiiploj'in;; it. 
AV/'f Aof/' iani. — The inventor mny lose hia right 

to a patt'iit by u>in^, ur nllonuii; oTJicrs to Ufe, hi* 
invention puuliely, It was L'uM^ule^cd tbal Dr. 
Hall bad net lost the right to u )ulcnt fnr his dis- 
covrry of certain objcct-gtaAAes, bceituse be bud nut 
made it known 10 utbcra, tjiougb it wu not imme- 
diatt^ly patented. If the aecrel uf an inveniiou ia 
kiiown only to a few pensonN, nnd nnr* of them pulv 
ic in ptAcLu-c, thru a patent afterwards obtained by 
Kny unn uf thcra is toIiI. Thi« luippeiicd to Mr. 
Tvunattt, btH*auiii: a bleacher, who had nut divulged 
the secret lo ituy other person but bifi twf> servant*, 
had ufcd the same kind of bicachine-liquor for 
aevrral years onterinr to tlie ilule uf Teuoulit'a pa. 
Cent. M'hrre a )M-rtM>n who xnught a patent for tn^ 
king ffpertikJcs intautinu*ly tuld an ari^uaintani^ uf 
the piiiiiuple of the invi-tititm, by which meaufl a 
ptrtton iif the snaie trNdv made ;i Himilnr fvur, nrid 
(hi-'invrntor, •rrin^ thrm in » shop wintlow, «aw 
ploj'ed a fnend tu purchase thcui (or hini, and the 
pdteiit WHB ofierwards grnnled, it was said to ha 
secure, llie queaCinn does not, however. ap|>ear 
to have bfcn brought before u court, and Mr. (iod- 
soti thiiiks thiit (be pNtrnt waa vonl, A pntmt for 
British iniperial vrrdi|.*rt» wj$ dcrUmt to be vuld, 

becauae the: ■■ • ■ f ' H, four mouths prior to tliu 

aeuling of il 1 tlir diticle undL*r udifTcreut 

iia&ia. \VhL , iautti^ made with a view lo 

try the efficacy ol an invention, ur the extent of a 
diacovcry, are a •v/nnfft and drdicnttng the invention 
to tlie public, wiikin the at'ituto of Jumes, haa not 
bnn dt-ridfd ; but it Wduld be dilfii'uU to say lu>w 
Dincb II dubolann' or inikrbine might be Used without 
rnniiing ttrriit rii^k of invididating the right to a 
patciit. ill riiini'r, It t^te inventor do nut, within 
two years, put hiji diseovrrji into activity, or do not 
justify hi« inartiuij, the putLut ia annulled. 

/Juration qf the Patent. — In England and the 
United ijtulrfc uf America, peteLta arc granted for ■ 
turtn nut exreeding fumtcrn yearft. The time in 
Knfclnnd maybe prolonu;e<t by a private act, and, in 
the United States uf Aoierita, by act of congrcai. 
Iu Frnnc-e, by the Ibw alicidy mcntionlcd, jMitenta 
are given for live, t«:n. or fifteen yeara, at the option 
of the invrnlur; but (bis Inst ti-rm il never to be 
prolonged without a parltouliir di-crro of Ihe Irgia. 
iature. The duration fur imported dUcoverica ia 
Dot to extetul beyond llie term fixed fur tbe privi- 
lege of the original inventor in bin own country.— 
[n France, if the iuvciitur ublaiu:* J |>atent in « 
foreign cuutitry. alter biivttig obtuincd one in I'rancf*, 
thi- pnlent is aiiowUrd- — Carfttl. In England, a 
car*rat it an inatiuiueut bj which notice is rL'quested 
tu be yivi-n lu the pervon who enters it, whenever 
any appUcalion ta made for a pateut for a certain 
invention, which ia therein dr*i:ribcd in grnciol 
tciins. It must be renewed (ntnualiy. It ia Mmply 
n ret|ueat that, if any other p<r«ou should apply tur 
II patent fnr the hoine ibiii^. Ibe prrfiTrnce may be 
givi-n lo Iiim nhu eutcrtd it. In llii* United Matta 
o( Amrncii, in case of interfrring B]iplinitionn I'tir n 
pMciit, ihcy arc auhmitud lo tbe arbitraliuu of 




MAGAZINE OF SCIENCE. 



i 



thre«p«rfonB) uppotntrd onr by each applicant, uid 
one by the secreUrr of state. 

Speci/lcot iun.— The inrention for which a p«tent 
ia (franlcd roust be accuralelj ascerUined and par- 
tioularly deuribed. The discloffore of the aecrac 
la the price of the monopoly, l^e fpeciAcmtion 
must be such that mechanics may be able to make 
the micbine by foUowiag the directions of the ipe- 
ciflcation, without any new invrotioiiB of thrir own. 
The patent and specificauon are linked together by 
the title givt*n to the invention in the patent, and 
the description of it in the ipecification. 'nie spe- 
cification muit support the title of the patent ; thtu 
a patent taken out for tapering. bnuih ia not sup. 
ported by tlie specification of a brush in which the 
briatlei are oi unequal lengtbi. h tnoat point oat 
what parts are nrw and what old. k must not 
oover too ranch ; if it does so» it 19 not effectual, 
even to the e:ttent to which the patentee wotrid be 
otherwise entitled ; as, if there be a patent for a 
machine and for an improTcment upon it, which 
«uiiioC be sustained for the machine, althoni^b the 
hnprorement is new and nacful, yet the grant alto- 
gether ia invalid, on account of its attempting to 
eover too much. A potent fnr a new method of 
drying and preparing malt is not suitaiDed by a 
apeci^catian in whioh is described a method for 
heating, he, ready-made malt : so a patent for an 
invention founded on a principle already known, for 
lifting fhel into the fire grate from below the grate, 
in the apecificatioa whereof was described » new 
spparatua, was held to be bad for not claiming the 
new instrument as the thing invented : so when a 
patent was " for a new method of completely light- 
ing cities, towns, and riUnget," and the apecifica- 
tion described improvementsupon lamps, the patent 
wu held to be void. The subject most be given to 
the public in the most improved itate hnuwn to the 
hiventor. A patent, in Bngland, for stef> trusses 
was held to be void, becaoae the inventor omitted 
to mention that, in tempering the steel, he rubbed 
H with tallow, which was of aome use in the opera- 
tion. The specitication must not contain a de- 
•rription of more than the improvrmrnt or addition. 
If thero be several lhini;8 specified that may be pro- 
dnoed and one of them is not new, the whole patent 
ia void. In England, if any consider able part of a 
manufacture be unnecessary to produce the desired 
effect, it will be presumed that it was inserted with 
a view to perplex and embarass the inquirer : thna, 
in I Term Reports, 602, in Turner's patent for pro- 
ducing n yellow color, among other things, ntinium 
la ilirectrd to be used, which, it appealed, would 
not pr<idace the desired effect, nnd, lor this reason, 
the validity f>f the patent might be itnpeac^hed. In 
the specification of Winter's patent, 1 Term Re- 
ports, 602^, a great number of aalts were mentioned, 
by which it ajtfteared that either might be used to 
make the subject of the patent, but only one would, 
iu fact, produce the etfect ; and, for tln» ri-nson, the 
patent wu held to be void. If tlic patentee maUeis 
Ibe article of cheaper materials than those which be 
has enumerated in his specification, although the 
fetttcr answer equally as well, the patent ia void. — 
In Engtand, if the improved manner of using the 
ioveotion be unintentionally Uft undex^ribcd, still 
«bo patent la void. (1 Moion'i Repttrta^ 1K9.) In 
Prance, the general rules, in these respects, are 
similar. 

CTohe eotUimueii.j 




OF ECLIPSES. 

I AfiMTJMrf/mia pi*if<f TCv) 

Or aU the various phenomena of the heavnifl, titer* 
are none which have created m murh curiosity, CL' 
cited so much interest, or caused so much surpria* 
throughout the world, as eclipse* of the nun amk 
moim ; and to those who are u^aoqumiitcd with tb« 
principle of astronomy, there is nothing, pertu^Cr 
which appear more catraordinary than tha moauwof 
with which they can be predicted. 

In the cjirlirr nges of the world, before wrigaot 
had enlightened the minds of men, appearanoei of 
this kbd were generally regarded as alarming devia- 
tions firom the established laws of nature ; and bur 
few, even among pliilosopbera tbenuelves, were abkr 
to account for these rxtmordinary appearanca.— 
At length, when men began to apply theoMelrea ta 
observattons, and wlien the motions of the odestiAl 
bodies were better understood, these phenomena 
were not only found to depend upon a regmLaroauni 
but to* admit of o natural and easy aolutiom l^Mnr 
ore, hflwpver, nations that still entertain Che 
superstitiuus itotiona respecting ecUpacs, p4 
Hx Mejricons and Chinese. 

Tbtu, wbea the inUnt mcKin bar drcUog ivtMra 
Wbeel* o>r tlw «un » tirosi) 4\ak. b«T tbadow (kits 
On vsrib's fair bt^aoin ; HukitMs chllU th« ft»Us, 
AoA drrary night kuvMU tiw fkc* of hosvcn. 
Henert«d from th« l«ko full oixpy ■ alat 
6llmin«n «(lh fe«bl« Inncour. India'* •ons 
AITrlgblvil In wild lumult rrnd lb» Ur. 
Itcfore hU idol god wilh buti'rou* >hn*k 
The Brsfhnian* (bUs i wlicn moti itir cy« of dUy 
t>aru hia uU'Checrtni ridtoiicr. Uum thr glainn 
K"i'n{*"(I ■'"y iBVMdM the wi)ud'ni%ti crawd. 
And acclmnsUuu ruihv* frwm tht b-flitiM 
or tbootinds. Uiai araood ibclr bluing p^^ 
Illol m antic rianc« noddUionaDt ■ong.— Zovea 

Many instances are to be found, not onlr in aa- 
(rient. but even hi comparatively modem ustoryi 
where the superstition of the times haa continiLed to 
connect the records of eclipses with the deUib of 
some remarkable event, which either happeoi aooa 
after or during tlieir rontiouance. But theae dctaik 
being foreign to the nature of the present jnper, if« 
shall procet^ to gjve an account of the causea, muf 
various kinds of ediptts of the sun and moon. 

As every planet, belonging to the sulor system, 
both primary and secomlary, derives its light from 
the sun, it muat cost a shadow towards that j]art of 
die heavens which Is opposite to the sun. This 
shadow is, of course, notlung but a privation of light 
in the space hid from the sun by the opaque body, 
and will always be proportionate Co the relative mag- 
nittid^s of thi* stin and plnnct. If the sun and planet 
were both of the same size, the form of the si 
cast by the pUnet would be that uf a cylinder, 
diameter of which would be the same ai thAt of 
sun or phuiot, and it woald nerer converge to A 
point. If tlie planet were Uirger than the sun, tlu 
shadow would continue to spread or diverge ; but 
as the sun ia much larger than the gn-atest of tb« 
planets, the shadows cast by any one of thc« bodia 
must CDnTrrs;e to a point, the distance of which from 
the planet will be iiruportionatc to Uic »i»e and dia- 
Unce nf the planet from the sun. The magnitiwhl 
of the Eun is such that the shadow I'ust by ench of 
tlie primary planets always converges lo a [>o\nt be- 
fore it reaches any other planet ; so that nut oimi aT 
the primary planets can eclipse another, yet the «hado* 

* Altlii>U){h th# Chiiv^v iirrfunn lh» tnml lidlculntia a»4 
iut<vrititi><M> err* moil tffi ddriri^ lite Itiit* al au ccii)M«, jaa 
they CAU lalL'oliit* Ibem nilh Tbr grrslctl prffeJ<i4n,, 



let which is Hcompuiied by iatellites, 
rertmn occasions, ecKpse these sateUites -, 
[not long enott^ to eclipte any other body. 
iw of a fitt«Uit« or moon may also, on cer- 
I, fall on the primary aud ecltpiie it 
ttpmi of Uie «nn and moon hnppen when the 
i m near her nodes, that is, when ihe is either 
i pUne of the ecliptic or very near it. Those 
B son happen only at new moon, or whci» the 
t U in conjuDction with the Kun ; whilst thoae 
ic moon happen at the time of /nli moon, or 
Qim moon is in opposition to the sun. The 



sun. earth, and moon, mast, therefore, always be 
nearly ia the tame stnight line at the time of an 
eclipM ; and coorersely, when tbeae three bodies ar« 
nearly in a ttroight line, on oclipse must take place. 
Hence it is evident, thnt an eclipse happens in con- 
seqoence of one of the two opaque bodies, tJie earth 
and the moon, being 90 placed as to prevent the 
sun's li^ht from hilling on thv other. See Che fbl- 
lowifig figure, which represents the moon paxsing 
through ttie dark shadow uf the earth, as she moves 
in her orbit N Z, while the earth moves in the ecUp<- 
ticRQ. 




ition of the moon between the sun 
prodncea an ecti{>se of tlie sun ; and 
ition of the earth between the moon and 
that its shadow foils on tJie moon, pro- 
edtpse of the moon. On these principles 
hole pbenomena uf edipscs depend, ojid admit 
n|ilete explanation. 

M moon s orbit we|T coincident with the plane 
Iptic, the moon's shadow would fall upon 
•nd occasioo a central eclijue of the sun 
ooiynnction, or new moon ; whilst the 
would fall on the moon, and occasion 
of that body at every opposition or 
ir as the moon would tlien always 
iptir, the centres of tlic nun, r^rth, 
Id all be in the fiame straight line at 
times. But the moon's orbit is In- 
Ftiie ecliptic, and funns with it on angle of 
flO' ; and. therefore, the moon is never in 
|e excqit when fihe in in one of her uodet : 
may be a considerable number of con- 
tand oppunitious of Uie son and moon with- 
taken place. 
u always at aomc distance from the 
when ihr is in one of her nodn:— 
is called her iafihtdf, which is 
according as the moon is on the 
ideof the echptic. Now if the moon 
there cannot be a eenirat ecHpie, 
hspjtt-n when thir moon is in one 
at tht rnomrnt of conjunction, winch 
the case ; and, of course, very few 
ises of the stm have taken place since ttic 
world. But the section of the 
(through whii'h the moon passM 
ipBcd) bring inach larger than ths 
the moon may be totalty eclipsed, 
^ sbv be at some distance from her node at 
nc of opposition ; but its duration will be the 
r tSie UBBLrer she is to the node. An eclipM of 
IS may also happen, although the moon oe at 
Sistance from hex node at the lime of cunjunc 
ihwt its form, as wcU as its duration, depends 
upon that dirtance. This circumstance 
the dif-ijiion of eclipsci into central, 
and portml. 
u-4iiing uf these terms most be obtiousto 





the reader, it is almost onneceaatry to gire an ex* 
planation of them. 

A central eclipse, is that in which the centre of 
the shadow folia on the centre of the body which is 
eclipsed. 

A total erjipse is the obwuration of the whtrfe 
body eclipsed. 

An annular eclipse is Chat in which ttie whole of 
the body eclipfird is hid, except a ring round its 
edge, which remains luniiuous. 

A partial ecli|>se is that in wludi ptft of the 
body is hid from view. 

iTobt tMntinued.) 



ESSENTIAL OR VOLATILE OILS. 

( Itentmfd /mm iMge llH.) 

Oil qf Bitter Almondt, is prepared by exposing 
the bitcer almond cake, from which the bland oil 
has been expressed, in a sieve to the vapor of water 
rifling within the still. The steam, as it passes ap 
through the bruised almond parenchyma, carries oET 
its Tolatile oil, and condenses along with it in the 
worm. Tlie oil which first comes over, and which 
falls to the bottom uf the wnter, has so pungent 
and penetrating a smell, that it is more like cyanogen 
gas tlian hydrocyanic or prussic acid. This oil baa 
a golden-yellow color, it is heavier than water ; 
when much diluted, it has an agreeable smell, and 
a bitter burning taste. When cjii>ased to the air, 
it absorbs oxygen, and lets fall a heap of crystals 
of benzoic acid. Tliis oil consists of a mixture of 
two oils i one of which is volatile, contains hydro- 
cyanic acid, and is poisonous; the other is less 
volatile, ia not poisonous, absorbs oxygen, and be- 
comes benzoic ucid. If we dissolve 100 parta of 
the oU of bitter almonds in spirit of wine, mix with 
the solution an alcoholic solution of potash, and 
then precipitate the oil with water, we shall obtain 
a quantity of cyonide of potash, ca|>able of pro- 
ducing 22 J parts of Prussian blu(^. Oil of bitter 
almondn cnmbines with the alkalis. rerfomers 
employ a great quantity of this oil in scenUug tb<dr 
suaps. One manufacturer in Pnris is said to (ireiiare 
annually 3 cwt. of this oil. A similar jMtsoiioua 
oil is obtained by distilling the following substsncei 
with water: — The leaves of the peach, {antyjftlaiHg 



HO 



MAGAZINE OF SCIENCE. 



/f^rtiCA,) the leavet of the bny-laurel, {frrnntu lauro- I 

^'-.--itnv 1 i1>f:- bark of thf f'M'c 'r- ^^'rrugpaHuM,) 

;rod kemelr^ i n-stonec* 

.'■ < 1- i»ntam liyl ' li rnitlArs 

ibrtn puisunaus, ftiid ihcy <tUo g^ni-rdir: benzoic acid, 
b; atiHorhiu; oxyi^cn on txpnsurr to oir. 

(hi qf Anist-tePiif is rAtrartrd bjr disitiUation 
fkmn the Kcdi of the pirn/jiitflla anUum. It ts 
either colorless, or has mei^ly a faiitC Tclbjw rolur, 
vtth thf> smeU and Caila of the leed. It fu>nrrctes 
in lamellar crystals at the temperatore of ^0 '. and 
does not melt again till heated to 64'^ nearly. Ita 
BpecifiL- KrHvity at 61^ is O'lMJoH.and at 77^, 0'9S57. 
It is sptubte ia all proporlions in alcohol of 0'S06 ; 
but ODif to the extent uf 42 per cent, in alcohol of 
0'84. When it becomes resiiioas by long cspoaure 
to the air, it loses tit coogvaling projwrtr. It con- 
iriita of two oili ; a solid atearesitence, and a liquid 
oleteswnce, which may be separated by compression 
of the cnld concrete oil. 

Oii t^ Berffamot, u extracted by preiifliire from 
the rind of the ripe fruit of tbe citru* terffamium 
and avrantium. It is a lioipid. yellowish lluid, 
harin; a amell resembling that of oran;;es. Its 
speriSc grurity Tariea from 08H8 to 0*B{<5. It be- 
camc« concrtte when cooled a little below 32". 

Oii of Cajejjut, is prepnred in the Moluccas, by 
^tilUoK the dry leaves of the melaieuca Ipvcnden. 
dton, Cnjeput ts a native word, signifyin^r merely 
n white tree. Tliis oil is green ; it has a banting 
taste, a strung snicll of camphor, tiirpetitine, und 
SaTine. It ia very fluid, and at 48^^ has a specific 
gravity of 0'918. Tlie calnr areros to be derired 
from the copper Teasels in which it is imported, so 
that it is runiavcd by distillation with Kstcr. which 
also separates the oil into two sorts; the l^rst which 
comes over haring a density of 0'897i the last of 
0-920. This has a green color. 

The Oil of Caritway, is estractcd from the srcJs 
of the carwn carui. It has a pate yellow color, 
and the smell and taste of the plnut. Iti sprcitic 
gravity is O'i'tiO, The seeds of the cvmittum 
Cj/mintmi, (cumin.) alTord an oil similar to the pre- 
ftt-diatc, btit not $o agreeable. Its specitic gravity 
is 0975. 

The Oil of Cassia, from the laurug catitia, is 
yellow passing into brown, has a specific gravity of 
l'071t and affords a crystalline stenrcuencc by 
keeping in a aomewbat open vefsel. 

The Oil of CAfinwtiiile, is extracted by di»t;llHlion 
from the Aowers of the mitrtrtinti rhamomiUn, It 
has a deep b]ae color, is almost op't(jue, iind thick ; 
and possesses the peculiar smell of the plant. In 
tba atmosphere it becomes broa-n and unctaous. 
If an ounce of oil of lemons be added tu 3 lbs. of 
this oil, they make it sepiirnte more readily from 
tbe adhering water. 

Other blue oils, liaving much analogy with oil of 
chnmomite, are obtained by dtstilEinz the following 
plants : — Roman chatcomilr, (antfiemii not/itht) 
the flowers of arnica itvoutana, and tUo»e of milfuil. 
{aeAtiiitn miHifoiia.) The last baa a specific gravity 
of 0-852. 

Oil f]f Cinnamon, i« extrartrd by distillation from 
tbo buk of the taurtis etnnamumum. It is pro- 
duced chiefly ill Ceyluo, from the pieces of bark 
unfit fur exportation. It is diiitiUcd ovtr nith 
dilliculty. and Uic proceig is promottd by the 
addition of salt water, and the u:^e of a low tlUI. 
It has at first a pale yellow color, but it bccomf*a 
brown with age. It possrases in a high d'-grrc hotti | 
the street boxning taste, and the sgiecabk amrll of 



cionamon. It ia hearier than water; its spooti 
gravity being 1'035. It concretes below 32* F- 
aod does not fuse again till heutetl tu 41^. It 
very sparingly soluble in water, and when agi 
with it readily separates by repose. U dt 
abundantly in alcohol, aod combines with ai 
into a viscid mass, not decumpoeed on ei\ 
tu air. 

When oil of cinnamon is kept for i '■ 
it dcpogtits a stcarcsscnce in Urge regul.i 
or yellow crystals, which mar be puUr- 
which melt at a very gentle beat into n coltirii 
liquid, which crysullises on cooling. It has 
odour intermediate between that of cifinninoa an^ 
vanilla; and a taste at first greasy, but afterward^ 
burning and aromatic. It crackles betweovj 
t«eth. It rv({uiresahigh temperature for distil 
and become!^ then brown and cmpyreamatic. 
very soluble in alcohol. 

The on of Cloveft is extrnoted from the 
flower buds of tbe caryophyllta arottiaticita. 
colorless, or yellowish, has a sfron^ smcU of 
cloves, and a burning taste ; its yptritic gravity 
1*061. It is one of th-,- least volatile oiU. and 
most difficult to distil. At thtr ev.-i of i < 
time it deposits a cryslnllinc roticrct^' i»il. A 
gtearextence ts obtained by boiling the bmisttli 
in aloohol, and letline the solurion cool. The i 
thus formed arc brilliant, while, grouped in 
vrichout tjisle and smell. Oil of dovrs hM 
markabic chemical properties. It distntvr* in slcnl 
ether, and ijcelic arid. It docs :: 
temperature of 4'' under 0" F., t\ 
to that CT)M for wvenil hours. It 
gns, becomes grtreu, then broftn.tn 
Nitric acid makr» it red, and it i' 

convei-ts it into oxalic acid. U mixed by 
degrees with onc>tlurd of its weight of s«lph 
acid, an acid litiuor is formed, at whose 
resin of n fine purple color Is fnniid. AfVcr] 
washed, this re«in hccouics htrd and brittle, 
dissolves it, nnJ i»Vr« a red color; and wa( 
cipitatrs it of a h^tod-^ed hue. It disao) 
in ether. When we asitate a mitturr of st 
caustic soda lye and oil of rlovt-s in rtiual 
the mass tliickens very soon, and forms 
lomelUr oryi^tsls. If we then pour water 
and drttil, there pluses along with Ihc water, 
qtianlity of an oil which dilTprs from oil of" 
both in taste and rhemicnl pri)[»crtif». Uoi" 
cooling, the li(|nor left in the retort kc»/ 
quantity of cryfltuUme needles, which being ai 
by expression from the altcaltnr liquid, are 
inudorons, but po-sess an alkaline taste, }< 
the burning taste of tlie oil. These crystala 
for solution from 10 to 12 purls of cold 
Potash lye produces similar ctrcctf. Ami 
gas transmitted through the oil is absort 
makes it thick. The courrrlc comhii 
formed remnins solid as long as the phial cot 
it is corked, but when opened, the c< 
becomes liquid : and these phenomena m»j} 
produced as tnany times ns we ptcasr. SnCibr 
nations arc dircomjioiied bv aculs, and iUr 
liberty has the luime faatc and *nicll as ftt Hi 
it hns A dsep red color. The aK. ' 
detect ihe prf*''nce of other oil«, a» ■ 
or SHSsafras, in that nf cli)vt:», biv .. 
latter, while ttie former may be tolaiiltu 
water by dij>ttllin^ the mixlun*. Tlie oil of 
fonnd in iHtmmcrt^ is not pore, but 
mtAtun; of the tincture ot pink» w di 



MAGAZINE OF SCIENCE. 



r 




Kcrid renn in thereby introdoccd. 
<hi»tiriitt-d wish other ntU. 
r, \a exiracled by di^tillatinn 
il}e Momhucwi nigra. Ic hu the 



- extraetcd by ilUtUIation from 

or tne niirthum famicitlum. It is efther 

r*T nf n yrllow lint, hns tlic Rmrll of the 

irtc (TTavity of 0-99:. Whrn 

Bcirl. it affordi* benzoin. It 

.u i;r- (■.mperatare of 11" F., ond then 

ltrr>>ure b lolid and a liquid oil ; the 

...<.. ring in rryntalline plaCea. It i« med 

7 for fcmtin* sonp. 

, rrmfuied l.iquQm. — The mbjitancef 

tit»l ront^iu a small quantity of 

. ^rhicb bcrome volatile along vriih Ibc 

-■T% in distillation, and progressively 

■' spirits become weaker towards the 

•c.ts3. The Tapors then condeoae Into 

Tbe«e oiU iidliere itronply to the 

L-ire it n peculiar acrid tntite. They 

lit to the vinoni wa«h from which they 

nnd combine with grc'itcr or leiia 



' •. — At tlw ordinary tempe- 

pir'ttiiy II nitite iuKd ; whi-n c<ir»1ed 

uowa the aspect nf tuct, and therefore 

'fly of ateareMcnct'. Its taste and smell 

iiJiTc ; it swims upon the surfat^c of 

■ -n of spirit contaitiing 30 per cent, of 

li tonieiimcs derives a green color from 

iV" worm of the ilill. When heated it 

onia yellow. ^V^e1l it baa become 

\\e agency of the atmosphere, it girea 

ttaiii to papL-r. It dissolves in G parts of 

us alcuhol. Olid in 2 of ether; and is said 

' illirc irhrn the Kpirit solution has been 

:< ic hot, and is allowed to cool. By 

frecxing D-.ixtare, the whiskey which 

£•> '- it fall. Caustic potash dissolves it 

y* 'id forms a soup «^oluble in 60 pnrtA of 

• fc-.i r It i< «b«orbed by wood charcoal, and still 

bttur by hui»e black; whereby it may be com- 

»leleJy abtlrsrted from bad ivbiskey. AL-cording to 

Bnobtkcr^ another nil mny aino be obtained from the 

fuidiiuin of the second distillation of whiskey, if 

salur«ted with sea salt, and a»>iin distilled. Thus 

re e>)t.iin n pale yellow fluid oil, which does not 

r^^ 't cold, possessed of a disngreenhle 

»' :-) taste. Its sjKcific graTity is 0-83.'t. 

t: a alrohol and ether. 

from Pofatv Sfjiritx, has properties 
: from the prei'rding. It is obtained 
:• quantity by continoj ag tbe distillation 
'T the alcohol has come over* and it 
ID the form of a jellowlsh oil, mixed with 
dispirits. After being agitated first with 
tuth a stronf; lolutiou of muriate of 
I tiled afresh, it possesses the following 
— It if colorlcM, limpid, has a peculiar 
a bitter hot taste of considerable per- 
il leaver no greasy stain upon piper, 
at D*' F., but cooled below that point 
like nil of anise-fieed. When pure it 
F. ; bat at a lower degree, if it contains 
Its spcrific grarity is OHlil, or 0*823, 
.'^ins a little water. It burns with a 
'hout smoke, but it eti<>ily goes out* 

•<'''• R wick. It diisnlvcil ill -'^ttl! 

It which it impnrts its taste 
jrming a lather by agitaliun. .^ 



diisolves in all proportioos in alooboL ChloriDO 
render* it ^reen. Concentrated tulphurle acid con< 
rerts it into a crim<H)n soltttiun, from which it is 
precipit4ted yellow by wbLit. It diseoNes in all 
proportions in noetic arid. Concentrated caustio 
lyes dissolve it, but give it up to water. It does 
not appear to be poisonous, like the oil nf com 
spirits; because, when given by spoonsful to dogs, 
ic produced no other etfect but vomiting. 

3. Tfif Oil of Br/jntii/, Of Grape Spinft, Is 
obiuincd during the distillntion of the fermented 
residuum of eipresscd gnipcs ; being produced im- 
mediately after the spirituous liquor has pajtMfd over. 
Jt is very fluid, limpid/of a peoctrattog odunr, and 
an acrid disagreeable taste. It grows soon yellow 
in the air. When this oil is distilled, the first 
portions of ic pass unchanged, but nfterwards it is 
decomposed and becomes empyreunialic. It dis- 
solves in 1000 partR of water, and communicates 
to it its pecoliiLr Listc and jimell. One drop of it 
in capable of giving a disagreeable flavor to ten old 
English gallons of rpiriti. It combines n-ith the 
caustic alkalis, and dissolves sulphur. 

Oti of Juniper, is obtained by distilling Janiper 
berries along with water. These should be bmised, 
because their oil is contained in small sacs or reser- 
voirs, whicli nni«t bi* laid open before the oil con 
escape. It is limped and colorless, or Fometimes 
of a faint greeniali vrllnw color. Its speeiHc gravity 
is 0-91 1 . It has the smell and taste of the juniper. 
Water, or even alcohol, dissolves very little of it. — 
Clin contains a very minute quantity of this oil.— 
Like oil of turpentine, it imparts to the unne of 
persons who swallow it, the smell of violets. Oil 
of juniper is frequently sophisticated with oil of 
tnrjtentine introduced into the still with the berries 
— a fraud easily detected by tlie diminished density 
of tlie mixture. 

TMe Oit of tawnder,\i txtncledUom tbe flower- 
ing spike of the larnndula Mpica. It is yellow, 
very fluid, has a strong odoor of the lavender, nnd 
a burning taste. Tbe specific gravity of the oil 
found in commerce is O'HDH at the temperature of 
72" F., and of 0877 when it bos been rectified. It 
is soluble in all proportions in alcohol of 0'B30, but 
alcohol of 0-B87 diisnlvcs only 4'J. per cent, of its 
weight. The fresh oil detonatea slightly when mixed 
wit]i iodine, with the production of a yellow cloud. 
There occars in commerce a kind of oil of lavender 
known uuder the name of oil of upic or oil of tpikft 
extracted by distillation from a wild variety of the 
lavatidflanpiC'h which has Urge leavca, and is there- 
fore called iatijhfia. This oil is manufactured in 
the south of Kurape. Ita odour is less character, 
istic than that of the lavender, reaembting somewhat 
that of oil of turpentine, with which it is indeed 
often adulterated. It is also so cheap as to bo 
sometimes used instead of the Utter oil. Oil of 
lavender depntits, when partially exposed to tbe air, 
a coQCrete oil, which resembles camphor, to (be 
amount of one-fourth of its weight. 

The Oil (if Xutmefff, ia extracted chiefly from 
mace, which is in the inner epidermis of these nuts. 
It is colorless, or yellowish, a little viscid with a 
strong aromatic odour of nulmegii, an acrid taste, 
and a spedfio gravity of 0048. It consists of two 
oils, which moy be easily separated from each other 
by agitation with water ; for one of them, which is 
more volatile and aromatic comes to the surface, 
while the other, which is denser, white, and of a 
lottery consistence, falls to the bottom. 
iTo 6tf (xriitimted) 



a 



112 



MAGA21NK UF SCIENCE. 



MEDICAL RECEIPTS. 

Bwrion Wairr. — Imitated by dissolTing ta a 
bottle of filtered water, 15 grains of carboaate of 
soJa, half a dram of taxtrate of »oda, «ith 80 minimit 
of wine of imn : before corking add 8 miuimB of 
fitilphuric acid. 

Campbell' M Green Liniment. — Made with 1 otmce 
eaeh of camphor and of extract of hemlock, 2 otinces 
of compound spirit of ammoiua, 6 ounces each of 
liquor ammoDte and of olive oil. For aweUings 
and enlarged joints. 

Camphor BaiU, auch aa Sdway'i , in perfiunerr, 
are made by grinding in a (ttarch-mill 6 pounds of 
very dry fftarch, 8 pounds of very dry white lead, 
cifting i>t through a lawn siere, and then mixing it 
with 14 pounds of very fine rice powder, l^en 
flbave down and dry 4H pounds of the best oil soap, 
and mix with the former. Next grind 1| pound of 
camphor in on iron mortar, with half a pint of 
Hungary water, and add Kradually half an ounce 
each of oil of ro<*rmary and of lavender. When 
reduced to powder, add a few pounds of tlie 
prepared soap, and after beating it well mix the 
vhole together, and make it in the same way as 
ambergris wash-balls. Used as a cosmetic, bat not 
aafiely. 

Camp Vineffar, is made by steeping in the best 
vinegar for & month 1 dram of cayenne pepper, 2 
table-Bpo4]m«ful of soy, amd -1 of walnut-ketchup, 
6 anchovies, chopped, and a small clove of garlic, 
minctid fine. Shake it frequently, Ktruin through a 
tammbt. itnd kvnp it well corked in small bottles. 

Catholicon Uvplicatum Rheo. P. — The doable 
catholicon of nicolai, or compound electnory of 
rhubarb, is prepared by simmering over a slow fire 
half a pound of polypody root, 2 ounces of succory 
root, 1 onncc of hi^uohce root, 3 ounces of the 
IflBTeB of agrimony and spleenwort, 6 pounds of 
water, till reduced two-thirds ; add 6 drams of fenncl- 
•eeds, strain and add 4 pounds of sugar, boil to the 
consistence of ^rup, and add 4 ounces each of 
extract of cassia and jiulp of tamarinds. Then add 
by decrees 4 ounces each of powdered rhubarb and 
aenna leaves, 1 ounce of liquorice root, 2 ounces of 
aeeda of violet, 1 ounce of the four cold seeds, half 
an ounce of fennel-seeds, and mix and form an 
electuary. It is too troublesome in the preparation 
to be much U!ied. ^Vitbout tlie rhubarb, and with 
hooey instead of sugar, it forms a good enema. 
It was formerly es&emed a nnivcnal remedy, bat is 
now disused. 

Chamberlain' a Hestorativt Pilli.— Dr. Paris dis- 
covered by RiuilyHiit that these pills consist of dnnabar, 
sulphur, HulphJste of lime, and a little v^etable 
matter, llie inventor, who resides at Ipswich, says 
the pills are the most eertain cure for scrofula, 
fistula, scurvy, and all impurities of the blood, but 
often take two years to effect » cure. 

CAamomile Dropt. — This nostrum is nothing more 
than spirits to which a little of the oil of chamomile 
has been added, for the sake of the odour and taste; 
but posaetsea none of the medicinal qualities of the 
flower*. 

ChtiMm Pemiionsr, — A well-known gout nostrum, 
•aid to have been invented by a Chelsea i^nsioner, 
and is prepared by making an electuary of 1 dmm 
of guoiac, 2 drams of rhubarb, in powder, ] ounce 
of nitrate of potass, and 1 ounce of flowerv of 
•ulphur, with 1 nutme]^, in powder. Dose, two 



table-apoonsJtil, night and morning, as a purgalivA] 
ami diaphoretic. 

CAimff's Worm Coseuj/et. — A po|)ular noctnuB, 
for worms, consisting of two preparation&, the 
of both of which is chloride of mercury. 

The yellate Jjizengei, are prepared by nixuig] 
1 pound of chloride of mercury, washed in aloohflj, 
with 4 drams of saifron that has been boiled in I 
I pint of water, and strained, and 29 pom 
white sugar, making the whole into a masa withj 
tragacanth mucilage, and rolling it out to an 
thickneas. Each loaenge should conuin 1 gnhi 
the chloride. The dose is one lozengr at bcd-tiiM«' 
and on the succeeding morning a brown loseuge ii 1 
to be taken. 

The Brown Losenyet. — ^Talce 7 ounce* of the 
chloride of mercury, washed as before, 3^ pounds 
of jalsp, 9 pounds of white sugar, and enoogb of 
gum tragacanth mucilage to make a mass. Eodir 
loaenge should contain half a grain of the ddoride. 

Tliese nostrums are by no means safe, as tha 
chloride Is wldom diffused equally, and may in : 
loxenges be in dangerous qoandty. When 
kept, also, or cxpoaed to damp, they may 
poiKonons properties. 

Cochrane'* Cough Medicine. — A nostrozn 
bears the name of Major Cochrane, is pi 
making a decocdon of the beads of white popplai* 
previously freed from the seeds ; rtraio this, Iml It , 
again with vinegar and brown sugar to the coo- 
sistenoe of syrup; then add sulphuric acid till it is 
pretty sour. 

Com Ptfuter. — The common green corn plaster ia 
prepared by melting 4 parts of Burgundy pitch, 
with 3 parts of wax, 2 parts of turpentine, and 
1 part of diarrtate of copper or vCrugo, and spr^ding 
the whole on cloth to a proper tlucknesa ; or mix . 
and spread 3 ports of mercurial oromnntacal pUster«| 
and 1 part of resin opiate plaster. Com 5o/M/Je«aj 
is solution of potass. 

Court PloMier, or Black Stickintj Plaster. — 1 
half an ounce of benzoin, and G ounces of 
spirit, dissolve and strain ; then take 1 ot 
isinglass, and half a pint of hot water, dissoJve iiS' 
strun separately from the former. Mix the !««#] 
and set them aside to cool, wht-n a jelly will be 
formed ; and this la warmed and brushed ten orj 
twelve timet over n piece of black silk, stretcbed:] 
smooth. "Ulien tliis Is done enough, and dry, 
it with a solution of 4 ounces of Chian turpentintpj 
in 6 ouoces of tincture of benioin. 

Dqffy^M Elixir, (/>ic«y'*.)— Take 4 ouncea_ 
senna leaves, 2 ounces each of rasped gnaiac < ' 
dried elecampane root, coriander-seedo, 
caraway 'Beeds, and liquorice root, 8 ounoesof i 
rusins, 6 pints of proof spirit. Digest for a ' 
strain through bihnloua paper, and add half a 
of treacle. Sometimes given to horses. 

Strinton'e Dcffy^e Elixir-'^-Take 3 pounds of' 
jalap root. 12 ounces of senna leavei,. 4 ounces caek^ 
of coriander-seed, anise-seed, liquorice root, and 
elecampane root, 1 gallon each of wine and water.' 
Digest for three weeks, strain, and add a gallon of] 
treacle. Do»c, 2 drams to G drams as a cannimttifCL j 

Dojmak Poicder, in prrfomery, is pneparW by, 
beating well in a mortar 3 pounds of cyprtta ; 
and dry damask roses. Sift the powder 
a fine cypress sieve, beating it and retumini 
it is sufficiently fine. The rosea make it ~ 
soft. 



XDiiDOM.-*Prtiit«d by.O. FajLMcu. A, While Uom Lant, MUa fad,— PubUahod bfW. Bajnaia, I i, ^lamostu lt««a 



THE 



MAGAZINE OF SCIENCE, 

find ^cj^ool of ^m* 



119.] 



SATUBDAY, JULY 10. 1841. 



[IK 



Fig. 2. 



iP - r^ 

Fig. 1. 





,D 




GODDARD'S OXY-HYDROGEN POLARISCOPE. 



HC 




Fig. 3. 



I. 111,'^KO. XT. 



MAGAZINE OF SCIENCE. 



THE OXY-HYDROGEN POLARISCOPE. 

( Met unusi from page 108, atuJ txttKludeii.J 

It haa been siready sUted that the object of the 
prMcding papers on the poUrixation of light hu 
beea to introduce and illustrate ihc polariicope of 
Mr. Goddord, of MrUicb the ftilluwiiig u a plain di*. 
tchplioa; merely prrmi»mg tbac the nuazle of the 
iiutniineDt, or that which is thus described, is to 
be fitted on the front ot a magic lanthoru, oiy-hj- 
drogcD microscope, Stc. 

Pig. 1. A, the cumpouud jet of the h^dro-oxjgen 
blawpiiie ; I), a pallet of lime ti;nited by the flame of 
1 jet of hydrogen tnd oxygen gasea impiuging upon 
it ; D, divergiug rays uf light refracted by the con- 
deniiug lenaes C C C, and falling upon a mirror 
FF. compoaed of ten pUles of thin flatted crown 
glaji*. placed in the elbow of a tube bent tu the 
polarizing angle of crown glass, C, conveying ruys 
of polarized light reflected from the mirror ; HH, 
a bundle of sixteen plntea of mica for anaiyiing the 
ligbt previously polarized by reflection ; E, a double 
reidecting uryslal (film of aelenite) pluced in the 
founi of the object>glaai I, which furma an image 
of the cr)-stal upou a di»c or screen at R. As the 
analyting bundle of mica H H, ia luaJe to revolve 
(or torn round), the image of the aelenite upon 
the disc undergoes all the changes, aud exhibita 
kltemntely the primary and roniplcmentary colors. 
This appaniiua buthe adTnatage of exhibitiag both 
the primary and ooroplementary colora at the tame 
time, one being reflected in the direction S, and the 
other transmitted and seen at R. 

The great advantage ut" polnrixing the light by re- 
ilectioD from a Dumber of plates, is the obtaining a 



beam of any required dimensions, of much greater 
intensity than by any other means ; for, whaterer 
single surface may be employed tiiat )>olarizes the 
light at the same an^le an the glass used (which, 
fur crown ghiss, is 56'' 45'), we obtain an additional 
quantity by laying on it a single plate of sacb glass, 
and a further quantity by the addition of a second, 
third, or any further number ; the quantity of Ugbt 
added by each Bueceeding plate being, however* 1cm 
in proportion lo the number of plates tlirougli which 
it has previously to pass. 

In this respect, the single image (^icol's) prism 
of Iceland spar ia decidedly the best for aualysiug. aa 
by this a great variety of objecu may be exbibitcdL 
Its application ia sbown in f)i(. 2, where E i* the 
srleiiite placed in the rays I) D D of polariied ligbt» 
an image of which is projected by the leuseft t. K 
is the aualysinc prism tltrougb which the ru|a of 
light RR are relracted. 

But there is one class of phenomena, nx. the 
rings seen to encircle the optic axes of crystals, 
the number of which iucrcasc in some crystals (tba 
topu, for example), witb the divergtfnre of the ray« 
of polarized light paaaing through them. It trill 
be evident, then, that the toumiahnes enable ua lo 
exhibit more of these nnga, and upon a Urger snle 
than the priifm, which will he belter understood by 
the arrangement shewn in fig. 3. D D U. con- 
verging rays of Iiij;bt polarizing by reflection ; I. a 
lens of short focus irsntiroitting a cone of light srith 
an angle uf divergence for it« rays R R, of 46'. E« 
a crysUl, say topax ; H, the tourmaline for aaalya- 
ing; 80 that, even for these purposts, the cost of 
the tourmahnes ia reduced one half by the polari- 
icope, as only one need b« used. 




OF ECLIPSES. 

{Hfaumed Jrmn ^f^e 109.) 

Tbk above figure represents n partial eclipse of 
the sun, which will be vieible to that tract of the 
earth marked NQ,0, the Une MN marks the 
greatest obscuration. 

If the distance b« very small, the eclipse vrlU be 
the greater, and continue the longer ; but no eclipse 
of the son can be either central or total, except the 
moon be in the very node at the time of conjunc- 
tion. But should she he in this situation when she 
ii at her least distance from the earth, and the earth, 
at the same time, st its least distance from the sun, 
then the eclipse vrill not only he central but total, 
and continue so for a few minutes. But if the moon 
happens to be at her greatest distance from the 
earth, and the earth at its greatest distance from the 
auu, the eclipse will be annular, or a small space 
round the sun's centre only vrill be hid from view, 
and a bright lucid ring round his edge will remain 
visible. 

If the moon be less than 17^ degrees from either 
node at the time of conjunction, her shadow will 
fall more or teas upon the earth, according as she 
H more ur lets within this limit ; and, of oootm, 



the sun will suffer a partial eclipse. And if ahe be 
less than Vl\ degrees from cither node at the time 
of opposition, she will pass through more or leu of 
the earth's shadow, according ma ahe is more or Im* 
within these lines, and, of course, ahe will cuffer an 
eclipse. 

As these Umita form but a small part of tba 
moon's orbit, which is HfiQ degrees, eclipaee boppcB 
but seldom ; however, in no year can there be feinv 
than two, and there may be seven of the sun and 
moon together — but taking one year with another, 
there are about four each year. But as the sua 
and moon spend aa much time below the horisoa 
of any place as above it. half the number of the 
eclipses will beinriaii/e at anyparticuUr place, and 
consequently, there will be only ttco eclipses visible 
in a year at that place, the one of the aun and the 
other of tlie moon.* 

Every eclipse, whether of the sun or moon, is 
risible at some place of the earth's surface, And in- 
visible at others ; for the rational horizon of every 
place divides both the eartli and heavena into two 
equal portions or hemispheres ; and as no celeatiel 

* ir iticra IM wvtn rcUpMi 1q any year, five of tlMMi ■■■t 
be of ih« sun and two of ibe moon. 



AIAGA2INE OF SCIENCE. 



lis 



I 



body can bf «rea ncept it b<t above the spectator's 
bw^a, it follows that nay eclipse which is visible 
IntlMOiie hemisphere cannot be visible in the other. 
fca W MB Ibe bodf which is eclipsed is belnw the 
Imrison of that other. If a lunar eclipse, for cz> 
— plii't hnppons at any hour of ni^ht, beiweea the 
IImi ofsun-strttiog aad san-risiuj^, at any particular 
ylBOK, it will be visible there, and invisible to the 
■dktbttaDls of the opposite hemisphere, who have 
ft* COB above their horizon at that time; fur i he 
nn afni tnoon are in upfwsite parts of the he;ivens 
«t tha iime of a lunar eclipse. And with respect to 
volar eoUpR*. it is evident that they can only be 
•oen at any place when the sun is above the horizon 
«C that plaet!. There is, however, a ditTerenee witlj 
t^anl to the visibility of solar and lunar eclipsca ; — 
for an ecl^se of the moon has the »ame appearance 
to ^^ tha iohabitiints of that heroiiiphere to which 
tlie moon is visible at the time, owing, in part, to 
tiM amaU distance of the moon from thf earth. — 
But an eclipse of the sun may be visible to »omti 
places and invisible to others in the same hemi- 
fphcr* of the earth, because the moon's ahadow is 
•akail is comparison of the earth ; for Its breadth, 
csclnding the prnooibra, is only about IKO miles 
wna ia Ct'Xitrul eclipfles.* Hence those places 
vhach are considersbly distant from the pnth of the 
ikailow vriU either bjivt no crlip<ic at all, or a very 
■oiaU one: while places near the middle of the 
•hadosr will have the ^eatest possible. There is 
■lao a difTcrrnce in the absolute (imentwhii-h a 
Mlar eclipse bappetu at the Tarioos pUcu it is visi- 
Ue ; for it appears more early to the western parti, 
«ad later to the eastern, on arconnt of the motion 
of the moon (aad, uf course, her shadow) from west 
10 cut. 

lo noct solar eclipses the moon's disc may be 
obserred by a televcupe lo be covered by a faint 
Ugbt, which is attributed to the leflcxioMfif light 
from the illuminated part of the earth. When the 
eclipses are total, the muon'a limb is surrounded by 
« pale eirctc uf light, which some uatronomrrs con. 
Mder as an indication of a lanar atmoe)ihere, but 
•tker^ ma ocr^-fionifd by the atmosphere of the sun, 
twcause it has hern observed to move equally with 
like lufi and not with the moon. 

f)r. Ilnlley, iu describing a central eclipse of the 
ich happened at London, in April, 1715. 
'^ althouigh the tlisc uf the sun wn« wholly 
by the moon, a luminous ring of a faint 
--bt surrounded the body of the moon the 
■ the time; and its breadth was nearly a 
'he moon's diameter. 

Mar rulipses, the moon seldom disipptars 

: and, on some occasions, even the spots 

■>tin?itisbed through the shade ; but this cjin 

'he case when the moon is at her greatest 

from the earth at thetimeof tbecclip!>p, 

p-ji . I arcr the moon is to the earth the dsik- 

•es» i-i 1 -.■■ '-iter. In some instances, the moon 

k*e duaip^aitd entirely; and the celebrated astro. 

•ottier. Ileraclius, has taken notice of one where 

tbe moon could not be seen even with a telescope, 

r nif^ht was remarkably clear. 

'•^h echpses of the sun and moon were long 

c^fiilered. by the i|:norant and supemtitiuits, as 

fRMfts of rtiV. yet they are ot the greatest use in 

*"^'""'''"*' "'H may be employed to improve some 

portnnt and useful of the iicirncrs..^ 

: Mju moon the eariM is prored to be of 

" * IwsombiA 11 tJi# Ul<i( thStloM t»n>duc«d by an ope<]u* 



a ff lobular form, the son lo beyrra/er than the eortht 
and the earth ^eatcr than the moon. M'faen thejr 
are similar in all their circumitaQcea, and lioppea 
■t considerable intcrviLl« of lime, they also servo to 
ucsrtain the real period of the moon's motion. In 
geogrnphy, eclip^rs are or considerable use, in de- 
termining the longitude of places, and pnrtirulirly 
eclipses of the moon, becaaso they are oftener viai- 
bie than those of the sun, and the same eclipse is 
of equal magnitude and duration at all places where 
it ia seen. In chronologr, both solar and lunar 
eclipses serve to determine exactly the time of any 
past event. 

For the purpose of finding the longitude of plaees 
on the earth, ecUpses of Jupiter's satellites are 
found much more UMeful thin eclipses of the moos ; 
not only on account of their htip|tening more fre- 
quently, but nn account of their instantaneous com- 
mencement and tennination. 

When Jupiter and any of his satellites are in a 
line with the sun, and Japiter between the 88teUit» 
and the aun, it disappears, being then eclipsed, or 
involved in lus shadow. When the satellite goes 
behind the body of Jupiter, with respect to a spec- 
tator on the earth, it is said to be occ*ttted, being 
hid from our sight by his body, whether in his 
shadow or not. And when the satellite comes into 
a position between Jupiter ami the sun, it cAAta a 
shadow on the face of that pUnet, whteh ia seen by 
a spectator uu the earth as an obscure round spot,— 
Lastly, when the satellite is in a line with JnpiCer 
and the earth, it appears on his disc as a roond 
black M|x>t, which is termed a transit of the satellite. 
As those phenomena appear at the same moment 
of aftjroluir lime at uU places on the earth to which 
Jupiter is then viiiible, but at different hours of re> 
/ff//re time, ai;cordiiig to tlie distance between the 
meridian of the places at which obsenrations are 
made, ic fallows that thia difference of time con- 
verted into degrees will be the difference of lonfltndo 
between those places.^ Suppose, for example, that 
a person at London observed on eclipse to be^n at 
11 o'clock iu the evening, and that a person at Bar- 
bndoes observed the same at 7 o clock in the eve- 
ning, tt is certain tlie eclipf.e was seen by both per- 
sons at the same moment of absolute time, although 
there is four hours difference in their manner in 
reckoning that time ; and this converted into de- 
grees (at the rate of 16 degrees to nn hour) ia the 
dilTen'nre of longitude between these two plucea — 
therefore, Uarbadoes is GO degrees vex/ fram Lon- 
don, the time not being so far advanced there as at 
London. 

Another phenomena, somewhat similar to an 
eclipse, sometimes takes place, by which the longi- 
tude uf places may be determined, nlthou^h not 
quite so easily, nor, perhaps, so occurutt-ly, as by 
the eclipses of Jupiter's satellites. This is the 
hiding ur obscuring of a fixed star or planet by the 
moon ur other planet, which t^krs phice when the 
moon or planet is in conjunction with the star. — 
AppcaruDces of this kind are termed oecultations. 
They are very Utile attended to except by practical 
astronomers, who employ them for the correction 
of the lunar tables, and settling the longitude of 
places, ai already stated. 

r To bo eontimtd.j 

* .llut^ute titnt ii that which >■ campnled fmm Iho nmm 
mnniftit: rtiaitre ia ibot wUcb la cninpttUil flum djfforcnt 
niAfnrntt. ; 



MAGAZINE OF SCIENCE. 



BOTANICAL NOTICES. 

1.EAVK8. 

Lkaves are among the most importaat vegetatiTe 
orguu. They may be said to perform the same 
office to pUnta which luoga do to animals, aa it ia 
through them thai vegetable breathing ia carried 
on. Bjr means of their pores and fine Teaaels, they 
absorb and tranamit the air and moisture which 
aurroond them ; and after thua aiding in the nour- 
iihment of the very excremitiea of tbu plant, they 
throw off from other pores not merely the super- 
abnndsnt juices, bat the air which they had pre- 
▼ioualy taken np, and that in a itate infinitely purer, 
aiid better adapted to the support of animal ciist- 
tence, than at first ; in fact, the very gas, (carbonic 
acid,) which planta absorb, la injuriouB to oa ; and 
that we want to breathe, which is oiygen, they sup. 
ply us with in return. 

The fdnctiona of leaves, therefore, are highly im- 
portant, and like the finer extremities of the roots 
require to be renewed from time to time : thoa, 
daring the greater part of the summer, fresh leaves 
are ariaing^when aatnmn comes, the whole fall off 
or decay away, leaving, aa is well known, herbaccoua 
planta dead, all but the root; and deciduotu treea 
Dare and leafless. 

Leaves have other uses, scarcely of less conse- 
quence. Those of the grass tribe by sheathing 
around it add much to the strength of the young 
and tender stem. Id trees they are so admirably 
placed as to shield the bud. and often the young 
flower, not only from ezteraal injur}', but from the 
too great tieat of summer, and where it is necessary 
from the chilling wiiida of winter. This latter pro* 
perty is seun in our evergreens ; and in some spe- 
cies of the oak ; where the leaves, ulthough AmA, 
still keep thtir place, till the swelling bud in the 
spring is ready to supply tlie tree with a new and 
living foliage. 

Ordinary leaves arc composed, first, of a skin or 
cuticle, which covera them on both sides ; within 
this is a green pulpy mass, called cellular ttMHue or 
farmchyma. and inside of all is a woody substance, 
branching out into delicate veins, intended not 



merely to convey the vegetable jnicea and secretioas* 
but to strengthen the more pi^py parta of the leaC 

Leavea vary ao much in shape end sixe, that 
scarody any twn plants (except in particular tribes) 
have them exactly alike ; thus in leavea are veiy 
often found sure marks to tell plants from each 
other. After dividing them into radical or root 
leaves, and caulme or stem leavea, they are cim' 
sidered with rrspecl to their pfMitiou, insertion, 
shape, surface, and texture. 

In thdr situation on the stem they may be wdisr 
aiiemate. (Pig. I,) that is, growing singly, first oo« 
on one side of the stem and iben one on the other 
— sppotite, or growing (2,) in pairs — trhirled, 1,3,) 
three, four, or more, growing out of the aame part 
oftheatcm — and imbrieated, (i,) when they fold 
over each other : sometimea they are scattered ap- 
puentJy without order. 

%.^-^ lb 



In their manner of growth leaves are ritber 9* 
presufd, (Fig. 1,) or growing rinse to the ateo>^ 
erect, (2,) or upright — j/atent, (3.) or spreading oat 
— hurizontal, (4,) — reclined, (^,)--aod SeyettdaU^ 
(6,) or banging downwarda. 




In their insertion or manner of attachment a leaf 
ia called etatked, (Fig. l.) if with a distinct atalk — 
jieggile, (2,) if joined at once to the stem — poymtffr, 
(3,) if abeatliing round the stem — clatjiing, {\,) tf 
the base dosed around it — deeurrent, (.'»,) if mn- 
ning down — perfoliate, (6.) if the stem run throng 
it — and connate^ (7,) whenever the base of tw» 
leavea are joined together. • 







The shapea of leavei are almost endle&s; they 
are either simple, compound, or doubly compound, 

I Simple leaves may be, I round — 2 oval~'S ovate, 
or ^g shaped — 4 oblong — h lanceolate — 6 linear — 



7 cordate, or heart abaped — 8 wpetfndate — 9 o l iww! 
date, that is, corfhite with the wider ptirt sway from 
the stalk — 10 reniformor kidney-bhaped— 11 ta^* 
tate or arrow sbajicd — 12 hajitate or like the haad 



t^ i% i¥ iT^ tfH ^ ^ a* 

e * 10 'it iir 3f 1^^ jsv 2^ 




MAGAZINE OF SCIENCE. 



117 



or • halbert~13 peitatt, tlut ii, with the ttalk 
growlof irom the middle of it — 1 4 tUltnid, or «oin«- 
tUoff like the Grerk letter Dclu— 15 runcinmU — 
1< iymfe, or gyitar stuiped — 17 lohHi—\S fiddU 
aUpi^ — 19 dictate, or fingered— 20 petlal§~~2\ 
Mhmafe, or like a band — 'i2 pinnatifid, that u, with 
lobe* cut down nearly to the inidhh~2:i;^er/jrtd/^, 
cut Uke the teetb of a comb. The loit eicht are 
WMatnTca. 

Compound teavet arc formed of many BicnplQ onea 
joined together. They arc called Otttate, temalf, 
tfig. I,) quctrmcte, qutnatr, (a.) A.r., as there may 
bt two, three, four, five, or more, eejiarate portions 



on the Keneral leaf atalk— vm^etf. (3.) when then 
are two distioct projevtiuoi below the blade of the 
leaf, u in the orange — ptnnaff. (■!,) whru many ire 
joined to aa to make two row> — and doubly pinnate, 
(A.) where several pinnate lenvcs are united; lo 
alM A leaf may be dnubly teniatf, or even ihrier 
temate. All iuttancca of this kiod form dtrnkl^f 
compound leaTeg, thongh the last term ia mostly 
applied to such as are loo much divided to hare 
Ihrir parta readily counted (aa in Fig. 6). When 
these parta are fine, like hairs, the leaf is called 
capiltactvim (Fig. 7). 






The fd^ea of leaves nrr another mark of distine- 
tion, whether they be cutn-f, (Fig. 1.) that is. with. 
«•! ootehea — cmate^ {2.) or scalloped— /ooMfJ, 
(li) — «rT * ale, (4,) or cut Uke a »aw — douhty «r- 
'**•' ' '<■ ) where a large and • small cut follow each 
sv*d, (6,)—indtnted, (7.)— erorfed. (8.) 
ii; as if it were kuawed — crisped^ (9,) or 
caricd — ciliated, (10,) Uut it, with baira around it, 




« to an eyo-Uah. 




i T 8 y lU 

Uke poinCi of learea are of no 1cm consequence. 
Tbry ue koown aa friMca/e, (Fig. 1.) if cot off 
'fii«, (2.) or blunt pointed — emarginaif^ 
ig « notch at the end — tridmi pointed^ 
\i^ — fnjipidate, (5.) or tapering into a bard point 
, —ta p tr m ff (6.) — uid hair poiultd, (7.) where the 
!■! tcnaiaatea in » long, weak, and fine point. 



0«r daily obserratioa informs us of many psr- 

(kalna hr«itlc!i these relative to this important 

VTe are accustomed to witness leaves 

with Ihoma, strings, baira and wrinkles.— 

W« kanw that the furxe bu«h ts scarcely furnished 

ftjih lama at all— numerous tboms supplying their 

piMVi Many plants can boast only of • few scales, 

inJ acme not CTcn these imperfect substitutes ; — 

V-aflesB dodder twines around the flax and 

>. choking them by Its embracot and stanr* 

tag thsfm by the absorption of the juices they hsd 

•tored up for their own use. On the other hand, 

bi tropical reginna the leavrs of many Tegetables are 

•f woriBans size — that of tlie talipot tree of Ceylon 

h oAcD 30 or 40 feet in eircumfrrence, snd sup- 

fsnedby % ttatk 12 feet long— s sini^li: leaf heint; 

ttlpkhle of shielding many prrsous fmm ihe Bttn and 

TUa. Thr Iravea of thr H«te tree, of Ihe banann. 

**4 of the cocoa out^ are ftlmoftt equally magoifi- 



f T 

cent. In our own country we witness nothing equal 
in magnitude to these ; hot we have instead of it 
richness of tint, and aa endless variety of apj^ear- 
ance. In the hotter regions trees are evergreen, 
always putting forth fresh leaves, and losing their 
olderooes. The forests, therefore, of countries like 
these are of a more uniform appearance than in the 
temperate regions. With us, aithough in the win- 
ter our woods are bare, yet during the remaining 
•easona we have an ever- varying succession of beauty, 
from the lively green, which the tender leaves as- 
sume in the spring, through the luxuriant uni) dark 
foliage of the summer, to (be rich and roellnw au- 
tumnal tints which prerede ** the/ait of the lee/,** 
casting ao bright a charm around the dying land- 
•cape, and contrasting with each other, no leaa in 
their decay, than tliey did in the previous times, 
when bnds were opening, and flowers shining in 
their freah and fragrant beauty. 



THE 



AND 



SUN NOT A GLOBE OF FIRE, 
PROBABLY INHABITED. 
TuK sun appears to be nothing elae than a very 
eminent, largf, and lucid planet, evidently the first, 
or in strictness of speaking, the only primary one 
of our system ; all others being truly secondary to 
it. Its similarity to other globes of the solar 
system with regard to its solidity, its atmosphere, 
and its diversified surfore. the rotation on it* axis, 
and the fall of heavy bodies, lesda us on to suppose 
that it is most probably also inhabited, Uke the 
rest of the planets, by beings whose organs are 
adapted to the pccuUor circnmstaaces of that vut 
globe. 

It may not, however, be amiss to remove a 
certain difficulty which arises from the effect of the 
sun's rays on our globe. The heat which is here, 
at the distance of ninety-five millions of miles, 
profluced by these rays, is so considerable, that it 
may be objected that the surface of the globe of the 
sun itself must be scorched up beyond all cod. 
ception. This may be very subatantiiUly answered 
by many proofs drawn from natural philosophy, 
which show that beat is produced by the sun's rays 
only when they act on a cslorifir medium ; titcy are 
the cause of the production of heal, by uniting 
with the matter of fire which is contained in the 
subetances that are heated ; as the coHiaion of flint 
aod sttel will inflame a magazine of gunpowder by 



U 



118 



MAGAZINE OF SCIENCE, 



putting tU the Ulcnt fire it containi into nation. 
But au iniitHncfl or two of the muiDer in which the 
folar rays produce tbeir effect will bring this home 
to our most common eiperience. 

Oa the tops of mountaini of a anffictent height, 
at an altitude whcrn clouds can very neldom r<iach, 
to shelter tbem from the dir«ot rays of the iud, 
we always find regions of ice and snow. Now if 
tht! solar rays themselves conveyed all the heat we 
find on this globe, it ought to be the hotteat where 
their cour8« is least interrupted. Again, oar arro- 
oauts all confirm the coldness of the appi?r regions 
of the atmofphcre ; and since therefore even on 
onr earth, the heat of any situation iir|M>nds on the 
aptness of the medium to yield to tlie impression 
of the isolar rays, we hare only to admit, that od the 
sun itself, the eloatic fluids composing it£ atmos- 
phere, and the matter on its aurface, are of sach a 
nature as not to be capable of any excessive nfffctton 
fWim its own rays, and this seems to be proved by 
the copious eniissiort of them ; for if the clastic 
fluids of the atmosphere, or the matter cnntaincd 
CD the surface of the sun were of such a nature as 
to admit of an easy chemical combination with ita 
rays, their emi5sion will be much impeded. 

Another well-kaown fad is, tbnt the solar focus 
of the largest lens thrown into the air will occasion 
no sensible heat in the place where it has been 
kept for a considerable time, though its power of 
exciting combustion, when proper bodies arc exposed, 
should be safficicnt to fuse the most refractory 
sttbstances. — Ucruchel. 



ESSENTIAL OR VOLATILE OILS. 

fRetumtd j'rum fage 111, and concIuthU^J 

Oil of Lemorw, Is extracted by prcsaare from the 
yellow peel of the fruit of the lemon, or citrus 
medica. In this state it is a ycUowiiih fluid, baring 
m specific gravity of 0'Hol7; but whea diittiUed 
along with water till three-fifths of thr oil have 
eome OTer. It is obtained in a colorless state, ond of 
ft specific gravity of 0-84 7 at 72' K. This oil does 
not become couerete till cooled to 4** below 0" P. 

The oil of lemons has a very agreeable amell of 
the fruit, which is injured by distillation. It is so- 
luble in all proportions in anhydrous alcohol, hut 
only 14 parts dissolve in 100 of spirits of wine of 
specific gravity 0'8.t7. This oil, e«j>eriatly when 
distilled, forms with moriBtic acid similar campho. 
rated compounds with oil of turpentiuet absorbing 
no less than 2i^0 volumes of add gas. 

Oil of lemons kept long, in ill-corked bottles, 
generates a quantity of sttfaressence, which when 
dissolved in alcohol, precipitated hy water, and 
onpomted, aifords brilliant, colorless, transparent 
needles. Some acetic ncid is also generated in the 
old oil. According to Brando, the specific gravity 
of oil of lemons is 0*878G. 

TAe Oii qf Mace, lets fall, after a certain time, a 
concrete oil under the form of a crystalline oruit, 
called by John mynWirtrie. 

TAe Oil qf Oranpe Flowen, called nero/i, is ex- 
tracted from the frob flowera of tlie ciinut auran- 
itiim. When recently prepared it is yellow; but 
when exposed for two hours to the rays of the sun, 
or for a longer time to did'use daylight, it becomei 
of ■ yellowish-red. It is very fluid, lighter than 
water, and bos a most agreeable smell. The aqueoas 
solution knovm under the name of orange-fiower 
nster, is used as s perfume. It is obtained ettber 
by dissolving the oil in WBter, or by distilling with 



th^ 
Th3| 



water the leaves either fresh or salted s ' 
being the strouicrr, but the last being tA 
fragrant preparation. Orange-flower water < 
by distillation, contains besides the oil, a (; 
which comes over with it, of a nature hith< 
known : it posiiessea the property of imptj 
water the faculty of becoming red with 
of sulphuric arid. The water formed 
olooc is destitute of this property. 
of the rose-color is a test in some measnn 
richness of the water tn oil. 

TTie Oil qf Parttey, is extracted from th< 
petroMelinum. It is of a pale yellow color, 
the smell of the plant, and consista of I 
separable by agitation in water. Its llqi 
floats upon the snrface in a very fluiil In 
stetreisence. which falls to the bottom, is but] 
and crystallises at a low temperature. Tl 
Crete oil melts at Hti*" F. 

Tfie Oil qf Pepper, Is extracted from ti 
niffrum. In the recent state it is liiD] 
colorlcsa, hut by keeping it becomes yet! 
swims upon the surface of water, la ^ 
resembles pepper, but is devoid of its hot 1^ 
7%e Oil qf Pcppermini , is extracted fi 
mentha piptfrita. It is yellowish, and t-ndu 
a very acrid burning taste. Its sprnfic gi 
0-920. At 6^ or 7* below O'' F., it deposii 
capillary crystals. After long keeping it ■ 
fltearesBcnre resembling camphor, provided 
bad been obtained from the dry plant gatl 
flower, but not from distiUation of the fres' 
Wlicn artificially cooled, it yields G per' 
steoressence, which crystallises in prisms wii 
sides, has an acrid somewhat rank taste, is 
in ether and alcohol, and is thrown down f 
latter solution by water in the form of 
powder. Peppermint water is choracl 
the sensatioD of coolnets which it diffa 
mouth. 

The Oil qf Pimento, is extracted from' 
lopes of the fruits of the myrius pimenta 
afford H per cent, of it. It is yellowish, 
colorless, of a ^mell analogous to that of ek 
acrid burning Uste, and a specific graritf 
than water. Nitric acid makes it fir^t n 
after (he effervescence, of a rusty brown h 
combine* with the salifiable bases, like oil of 
TAe OH of RhhdiiitH, is extracted from tl 
of the conroieoiiu scopariwt. It is very flu 
has a yellow color, which \u time becomes r 
has somewhat of the rose odour, and is \ 
adulterate the genuiuc otto. Its taste is bit 
aromatici which it imparts to the otto as vv 
fluidity. 

The Oil ofRosrt, colled also the 
is extrnctcd by distilUtiaD from the 
roM rentlfoHa and sempwTJrs m . Our nattv 
furnish such small quantities of the oil, th 
are not worth distiUing for the purpofe. '7 
wsy of operating is to return the distiUnf 
repeatedly npon fresh petals, and eventually 
the saturated water with ice; whereby a hltl 
raceons oil is deposited. But the oil Oius oi 
has not a very agreeable odour, being iiiji; 
the action of the air in the repeated distil] 
In the East Indies, the atur is pbtamed by 
fying ro«e leaves in earthen pans in alternate 
with the oleiferous seeds of a species of dj 
culled gengeli, for several days, in a cool sit 
The fat oil of the seed sbsorbs thft *— ***■' 
the rose. By repcstiug tbis praasva wfll 



of 
Bcteri 



petil 



J 




MAG.VZINE OF SCIKNCE. 



19 



v>d the Mine seed, thii becomrs eventawUy 

ti, anfj being then exprosscd furnijhes Utc oil. 

Tke turbid liquid tbtu obtainett is Ic/t at rest, in 
«cU-cJu»od vcskU. wben; it gets cUrifted. The 
tiffer of uil Hut floats on the top i« theu drawn off 
b| • capillary cotton wick, and subjected to dis- 
taUtioQ aloog with water, whereby the Tolatile utto 
l» Mp«ral«d Aram the fat seed^U. 

T^ oil of roses ia colorless, and posiesses the 

lell of ro«««. which ia not however agreeable, 

tifllst wtnTi ililfuscd, for in iU conneiitraLed state it 

I -^AOt to the nottrils. aud is apt to 

los. U» taste i* bland and sweetish. 

II water, and at tlie temperature of 

I cravity cumpored to that of water 

L^wif » •' -i^. At lower temperatures it becomes 

^^kpvte and butymceoiu ; and afLerwurdK fuaes at 

Ik It is but slightly soluble in alcohol; lOaU 

yirts of tbis litjuid at OHOGduiaolringonly 7^ parta 

tf 5ir* f'. Tliis oil coosidls of two parts, the stear- 

— eo oc and olciesseoce ; the latter being the more 

VOlfttUii odoriferooi portion. 

TAm on uf Rotmarjf, is extracle<l from the r09- 

■ ■ r ^w w t oJirialiM. It is as limpid as water, has the 

tB«ll of the plant, and in utlicr rc«]>ertfi resembles 

oil of lurpenliiie. The oil found in commerce has 

1 ijr. ih, gravity of 0-91 1, which becomes 08886 

ttion. It boils at 321) P. (occasionally at 

1 1 IS soluble in all portions io alcohol of 

U Mju. \\'hcn kept in imperfectly closed vessels, it 

depocita a a tear rue nee to the amount of one-tenth 

ito wvigbt, resembling camphor. It is someCimea 

led with oil of turpentine, a fraud easily 

dfteeird by Sliding aubydroiu alcohol, which dis- 

'v Ute oil of roeemary, 

' ^ Si^rofht is extracted from the ttigmata 

ol (be crocMt tatiru*. It is yellow, very fluid, falls 

to the bottom of water, diifuseii the penetrating 

' 1 be plant, and has an acrid and hitter taste. 

uc. 

* ..' t -- <{f Sajuafrai, is extracted from the woody 

MOt of th« launu Mcxiafraa, It is colorless, bat at 

Att cod uf a certain time it becoaiea yellow or red. 

U has ■ peculiar, sweetish, pretty agreeable, but 

hnt burning taste. lu specific grsfity is 

tng to Bonostre, this oil aeparatts 

• water into an oil lighter aud an oil 

IU mis fluid. When long kept, it deposits 

in transparent and colurlesi crystals, 

i.^»*- th^«mell and taste of the licjuid oil. 

irine, is extracted from the leaves 

^ itahina. It ia iimptd, and baa the 

Mid Us(« of tbe plant, whidi is one more 

v« of volatile oil than any other. 

'HI ^ ToBMjf has a specifir gravity of 0*946, 

pmctratiog odour of the ianacftum vnigarc, 

aa acrid and bitter taste. 

<M (^ Turjieuiinc, commonly called essence of 

It ia extracted from sererat species of 

A semi.tjtjuid rcsiaous substance which 

certain trees of the ^iiie tribe, and is 

by distilling the resin along with water. 

This Oil is the cheapest of all the volatile species, 

' '1. contains a UctJe reain, from 

by rc-distilUtion with water. 

■ ^1,, tM.ipuJ. very fluid, and has a very 

nrll. lu specific gravity st CO' is 0-872; 

hi', spirit on sale in the shops is 0-8/6. 

j>U always reildrns Utmus paper, because it 

httle suLviaiv acid. 

parts of spiri(s of wine, of apccific gravity 

H4| dtalve only 13^ of oil of turpentine at 72"!'. 



M'hen agitntcd with alcohol at 0*830 the oil retains 
afterwards one-Afth of its bulk of the spirit; hence 
ttiis proposed method for purifying oil of turpentine 
ia defective. Tbe oil if left during four months in 
contact with sir is capable of absorbing 20 times its 
bulk of oxygen gas. One volume of rectified oil 
of turpentine absorbs at tbe temperature of z?**, 
and ,under the common atmospheric pressure. 163 
times Its volume of muriatic acid gas,, provided the 
vessel be kept cool with ice. This mixture being 
allowed to repose for 2-1 hours, produces out of the 
oil from 2G to 47 per cent, of a whtto crystalliuQ 
substance, which subsides to the bottom of a brown, 
smoking, translucent liquor. Others ssy that lUO 
parts of oil of turpentine yield 110 of this crystal. 
Uoe matter, which was called by Kind, its diS' 
icoverer, artificial camphor, from its resemblance in 
Amdl and appearance to this snbstance. Uoth the 
solid and the liquid are combituktions of muriatic 
acid and oil of turpentine ; indicating tiie existence 
of a Btearioc and an olcinu in the latter substance. 
The liquid compound is lighter than water, and is 
not decompoR'd by it, nor does it furnish any more 
solid matter when more muriatic gaa is passed 
through it. Ttie solid compound, after being washed 
first with water containing a litile carbonate of soda, 
then with pore water, and fiaally purified by subli- 
mation with some chalk, lime, ashes, or charcoal, 
appears as a white, tran&luccnt, crysulUne body, 
in tbe form of flexible, tenacious needles. It swiou 
upon the surfsce of water, diH'uses a faint smell uf 
camphor, commonly mixed with that of oil of tur- 
pcntine, and has rather an aromatic ibun a cam- 
phorated taste. It does not redden litmus paper. 
Water dissolves a very minute quantity ; but rold 
alcohol of 0*806 dissolves fully one-tiiird of its 
weight, and hot much oiore, depositing, as it cools, 
this excess In tbe form of crystals. The solution 
ia not precipitated by nitrate of silver, which shows 
that the nature of the muriatic acid is perfectly 
masked by the combination. It is composed, In lOO 
parts, of 7C'4 carbon, 9*6 hyilrogen, and 14 muri- 
atic acid. The muriatic acid, or chlorine may be 
separated by distilling an alcoholic solution of the 
artificial camphor 12 or 14 times in succesaioa with 
slaked lime. 

(Jil of turpentine is best preserved in casks In* 
closed within others, vrith water between the two. 
lt» principal use is for making varnishes, and as a 
remedy for the tape-worm. 

The Oil (/ TAyute, is extracted from the thffmut 
Htyyllum. It is reddish yellow, has an agreeable 
smell, and, after being long kept, it lets fall a crys- 
talline stejfresseuce. It is used merely as a perfume. 

The Oif r^^VorfHtcwd. is extracted from the 
ariemisia ahttiiihiutn. It is yellow, or sometimes 
green, ond possesses the odour of the plnat. Its 
taste resembles that of wormwood, but without its 
bitterness. Its speriHc gravity is 0-urU3, accord- 
ing Co Briseoo, and 0*9725, according to Brando. 
It detonates with iodine when it is fresh. Treated 
with nitric acid of 1*25 specific grarity, it becomea 
6nit blue, and, after some time, brown. 



MEMORANDA. 

Iron, — Every person knows tbe manifold uses of 
this truly precious metal ; it is capable of being cast 
in moulds of any form ; of being drawn out into 
wires of any detired strength or fineness ; of being 
extended into pUtiis or sheets $ of being beat ia 



MAGAZINE OP SCIENCE. 



every dirertion ; of being shBrpened, hardened, uitl 
nof^ened at pleajiurr. Iron aerommodatrs itself to 
all oar wants, our desires, and even oar caprice ; 
it U equally «-*rviL-eubIe to the arts, the sciences, to 
agricultnre, and nar ; the same ore furnishes the 
vword» the plougb&hare , the scythe, the pruning- hook . 
the needle, the graver, the spriog of a watch or of a 
carriage, the ctUael, the chain, the anchor, the com- 
pjui, tlie canaon, and the bomb. It ti a medicine 
of much rirtae, and the only metal friendly to the 
humuu frame. The ores of iron are scattered over 
the crust of the globe with a beueficcot profusion, 
proportioned to the utility of the metal ; they are 
found under every latitude and every tone ; in every 
mineral formation, and are disseminated in every 
soil. — Dr. Un'i Dictionary qf Manufactures. 

Seo Wormi. — Tliese animals, which are so per- 
nicious to our shipping, appear to hare the same 
office allotted to them in the waters, which the 
termites or white ants have on the land. Were it 
not for their rapacity, many rivers, and parts of the 
ocean itRelf would be choked with the bodies of 
trees which arc annually carried down by the rapid 
torrents, and many of them would last for ages, 
and probably be productive of evils, of which we 
cannot in the present harmonious state of thin^ 
form any idea ; whereas now, being consumed by 
these animals, they are easily broken to pieces by 
the waves, and their entire dissolution is oherwords 
rapidly effected by a variety of canses. 

Human 7Vme Pi>rc. — The following singular 
account appears In a recent number of a valuable 
French work, the '* Bibliott'que Universelle," 

J. D. Chevalley, a notive of Switserland, aged 
sixty-seven, has arrived at an astonishing degree of 
perfection in reckoning time by an xnlemaf move' 
went. In liis youth he was accustome^l to pay 
great attention to the ringing of bells, and vibrations 
of pendulums, and by decrees he acquired the 
power of continuing a sacceasion of intervals exactly 
equal to those which the vibrations or sounds 
prodnced. Being on board the steam-boat on the 
Lake of Geneva, on July 14. 1B23, he engaged to 
indicate to the crowd about him the lapse of a 
quarter of an hoar, or as many minntes and seconds 
OS any one chose to name, and this during a conver- 
satinn the most divrr«ilicd with those stauding by ; 
and farther, to indicate by the voice the moment 
when the hand pn9i>c-d over the qanrier minutes, or 
half minutes, or nny other sub>divt»ion prCTioaiily 
stipulated, during the whole course of the experiment. 
ThtB he did without mistake, notwithstanding the 
exertions of those about him to distract hiiatleDtian. 
and clapped his hand at the conclusion gf the time 
fixed. His own account of it is thus given : — 
" I have acquired by imitation, labor, and patience, 
a movement which neither thoughts nor labor, nur 
any thing can stop. It is similar to that of a 
pendulum which at each motion of going and re- 
turning gives me the space of three seconds, so 
that twenty of them make a minute, and these I 
add to others continually.*' 

Humming of Gtiait, — It appears very probable 
that the humming noise emitted by the gnat when 
fljring about in a dark room is useful to the insect 
itaelf, for, as it would be differently modulated ac- 
cording to its distance from, or nearness to, sur- 
rounding objects, it may have the effect of prevent- 
ing its injuring Itself by knocking against obstruc- 
tions to its flight. As a proof of the great difference 



in »oandi orising from even but trifling cmaea* we 
have only to take a card in hand and whistle agaiasl 
its edge at a little distance, and then a greater dis- 
tance, and then against its flat surface at a greater 
or less distance, and we shall obserre that the tone 
widely differs under each of tboe drcumttanoM. 
Now, if ire suppose that the gnat knows, from either 
instinct or experience, that aoands thus differ ac- 
cording to such circumstances as the abore. it ms| 
learn its situation in a dark room by the rariatftsB 
produced upon iu piping noise (which may thus be 
as serviceable to it in the dark as its sight in the 
day time), and avoid breaking its vrings, or other- 
wise hurting itself by flying agunst anything tn its 
way. In the same manner, probably, one may erplahi 
the utility of the humming of the cockchafer (IfMns* 
tha f>uitjari»), the dung-beetle {Geotmpta «tferv9- 
rrirtttij, and many othej insects. 

Tht Veiocitiet ^ Wind.—yix. John Smeaton, 
the late celebrated engineer, has given in the 
" Philosophical Transactions/' vol. 51, the ve- 
locities of wind, corresponding to the usual denomi- 
nations in our language, Theee ore founded Ln 
u great number of observations made in the cuurac 
of bis practice in erecting wind-mills, and are oa 
follow :^ 

Light airs. .from.. I to 3 miles per hoar. 

Broen 4 to 5 miles do. 

Briakgale 10 to 15 miles do. 

Fresh gale 20 to 25 miles do. 

Strong gale 30 to 35 miles do. 

Hard gale 40 to 45 miles do. 

Storm &0 to 60 miles do. 

Hurricane 80 to 100 miles do. 

Tht Light of the Moon and Planeta is considered 
by Professor Leslie to be caused by phoflphoreaccat 
matter, and not by mere reflection from the sun. 
The light falling from the sun upon the moon's anr* 
face appears to him to be almost entirely abaorhed, 
and exerts there a power to cause the projection of 
a still greater quantity of luminous particles, whidl 
bad previously Isin combined vrith the substoDcc. 
which be supposes bears a resemblance to the vaX" 
phatc of barytcs. 

Bleaching Ivwy. — Antique works in ivory that 
have become discolored may be brought to a part 
whiteness by exposing them to the sun under gl 
It is the pariicutor property of ivory to retl 
action of the sun's rays, when it is under 
but when deprived of this protection, to become 
covered with a multitude of minute cracks. Many 
antique pieces of sculpture in ivory may be aeea, 
which, although tolerably white, are. at the 
time, defaced by numerous cracks ; this defect can- 
not he remedied; but, in order to conceal it* the 
dust may be removed which has insinuated itself 
into the hssures, by brushing the work with warm 
water and soap, and afterwards placing it under 
glass. Antique works in ivory that have beoow * 
discolored, may be broKbed with pumice sttaie, 
calcined and dilated, and while yet wet placed nn- 
der glasses. They ahould be daily exposed to the 
action of the sun, and be tamed from time to time, 
that they may become equally bleached ; if the 
brown color be deeper on one side than the other, 
that side vriU, of course, be for the longest time ex- 
posed to the sun. The bleaching may be ocoele* 
rated by frequently repeating the operation jost da- 
scribed. — Repertory qf Art*, 



a piuE 

3 



Umodm — I'rlnteJ by O. Fhakcii, 6. While Itarni! L»nc. Mile Eii4 — PublliliiMl Dy W, B>m*tM. II. PalemMitM Row. 
CommuaicaUinu, v*vhii:h are aaswrrpd Monthly.) (o be adOmsed to Ibo Editor, at 37, Col1*][C Orovf. MU« Ead Rsad 



anH ScDool of 5lvti5. 




m. 



111. NO. XVf. 



ELECTRO-MAGNETISM. 

tOnUmwfi frma pagr 978, ruf. M.i 

The last jiaper upon thii sabjecc gave an iccoant 
of Tsrioui electro* niBgnrlic rotatiimH, protlnoed 
upon wirtra i-onvcying the electric lluid aloii^ tbcm, 
aided by ibe eflVcts uf the propinqaity of v mmgnet. 
Tbt' present article continues llie subject by «how- 
jng that ntagnetj theaiMlves, if made free to rrvoWr. 
and subjected, in particalar wayi, to electrical car* 
rmtf , will olao trToKe upon their aici. 

Ampt-re was the first who tucceeded In accom- 
ptifihinK the reroluUou of a mu^net on its own axis, 
ilia apparatuB for thin pur{H)ae was a magnet, sua* 
pended vertirally on a i>oint. and with n mercury 
cup at the upper end, it beini; free to moTe around 
its centre. The lower half of the magnet wai im- 
mersed ID qaickaiWer — connected wiili which quick- 
silver, W88 8 serond mercury cup. Aa soon as con- 
nection was made between the poles of the electro* 
ma^etic battery and the mercury cups, the fluids 
pasaed through the upper half of the magnet, and 
occasioned it to rotate. The principal defect of the 
above arrangement was the weight of thp'Inrgc quan- 
tity of mercury employed, and the friction It ocoa* 
sioncd against the sides of the magnet, so retarded 
the mrition, that a very powerful battery was indis- 
penaaSlc. 

The same phenomenon has been exhibited in 
various ways ; the principle on which it depends \», 
That the electric current should pass through one 
half of the magnet only, so as to act exclusively on 
the pole which is situated in that half, and after- 
wards be diverted from the magnet, and made to 
pass Bway in such a direction as that it shall not 
affect the other half of the magnet. In the experi- 
ment of M. Ampere above relnted, tl»c elertrir car- 
rent, after traversing the upper half of the magnet, 
passes into the mercury, and being diffused through 
it, acta in no sensihle degree on the lower pole of 
the magnet, and dnes not interfere with the rotation 
produced by its influence on the upper pole. 

The same object is attained in the following man- 
ner, by an apparatus represented in fig. 3, and in 
section in fig. '1 ; a magnet, pointed at both ends, is 
supported below by an agate cup, fixed on a item 
rising firom the bottom of the stand ; whilst its 
upper point t» lightly pressed npon by a screw with 
a milled head, pRAfing through a screwed hole at 
the top of an arched bead, winch forms part of the 
sustaining frame-work of the apparatus, near the 
middle of the magnet. This frame supports a stige 
in the form of a ring, tltrough the centre of which 
the magnet passes freely, and carrying a circular 
cistern of mercury, which also surrounds the mog- 
net, without touching it. A similar cistern of mer- 
cury snrrounds the lower stem, which supports the 
«gule cup. A copper wire projecting into the in- 
tenor of each of these dstems, pa»>ses out through 
its sides, and being bent upwards, terniinatec in a 
anmll cup holding a little mercury, for efTecting the 
oommunication with the electro-magnetic battery 
by wires in the usual manner. A small wire 
pointed and amalgamated at its end, is affixed to the 
middle of the magnet, immediately nhovc the cis- 
tern, and IB bent so aa just to dip into the mercury 
contained in the cistern. A simibir n-irc, proceed- 
ing from the lower end of the magnet, is made to 
dip into the mercury contained in the lower cistern. 
The lower half only of the magnet being thus made 
to form part of the gaU-anic circuit — which is con- 
Ciauous from one cup through the cisteru of mer- 

■ 



cury. the wire belonging to the magnet, the mapact 
iUelf, the other wire, the other ciftem of roerciiry, 
and the wire terminatiaE »» the other cup, rec/'ites 
the exclusive influence of the electric current which 
passas throngh it, and begins to rotate with eon* 
aiderable velocity round the axis which is oofwU- 
tuted by its upper and lower points of support. — 
The degree of rotatory effect will depend very mueh 
on the delicacy of the suspension of the magnet, M 
that the friction at the points may bo as small aa 
possible. 

Different forms have been given to the magnet in 
the above apparatus, all, however, having the same 
obvious intention of diminishing friction and ba- 
lancing the magnet equally upon a centre. One of 
the more successfnl as well as the more effective of 
these pieces of apparatus, is that shown in fig. 2, 
and which will be readily understood by the preced- 
ing descriptions, and by that which foUoa-s, ei|iliin- 
ing the action of a double apparatus, by which ro- 
tations in opposite directions maybe exhibited a« 
the same time, and, by the same current, by phiring 
the poles of the one in a contrary direotioa to thoM 
of the other magnet. 

Fig. 1, represents this double appsratns. Two 
bar magnets k II and C D, are bent, so as to form 
a shoulder in the middle, io which arc anioll boles 
drilled, by which they are suspended on pivots, and 
made free to revolve. On the upper side of t^e 
shoulder small cups K snd F are attached to con- 
tain mercury. From each of these cups a soull 
wire is bent downwards, to dtp into the mercury 
contained between the concentric cylinders on the 
stand ; proceeding from the upright ^tem is a bnsi 
wire, I K, of a staple fonn, whose ends dip into tl»e 
small cups on the bendings of the magnets; the 
circuit is fortned by dipping the connecting wiraa 
into the cup U at the top, and the cups L M on 
each side of the apparatus. The nia|:neta then 
commence a very rapid revolution in the same or 
contrary directions, according as dissimilar or aiiai- 
lar poles of the battery are employed. H is a siercv 
for adjusting the brass wire I K, so that its ntre- 
mities may communicate properly with the atnall 
cups. 

By this mode of making the experiment, tfM 
whole length of both the magnets is ezpOfcd tft 
view, and by having the north pole of the one, and 
BOutJipoleof the other subjected to aimilariy eter- 
trifled wires, the different directions of rotation of 
dissimilar poles can be observed at one and the 
time. 

{To tm eottHnutd.) 



LAW OF PATENTS, 

f^ It^tumeJ from pit gi lOg, arul foneludtd. j 

Enrolment. — In England, a patent is void nal 
It is enrollcil. The time allowed for the enrotoMiC 
Is now generally confined to one month- Enrol- 
ment cannot be dispensed with, though it be to k«ni 
the specification secret. After a patent has paaMO* 
the time for enrolment cuauot be enlarged vrithanC 
an act of parliament. In the United Ststes 
America, the patent, after the seal of the United 
States of America is affixed, is recorded in a boolc 
kept for the purpose. 

InfringemvHi. — Whether any act is really an in- 

fringement of the patent, is a question for the jorr* 

The using the least jiart of the manufacture u a: 

infringement. In Manton r. Msnton, the infringe' 

i meat consisted ia making a pcrforatioa in the bam' 



im 



3 



MAGAZINE OF SCIENCE. 



12.3 



Oer of n i^n in a direction a little diffrrent froni 
llui ID Uwpatrnt article. If the article manufac- 
tored be of ■ ditfereut form, or made with alight 
mkI Immaterial alicrdtions or additions, if the maau. 
faBtum are really and gubitantiilly the same, the 
7»Btrn'rr is entitled to n rrmrdy, a* where the |K«ii- 
thc diHerent ^arta of b steam eoginn were 
i. Where reveral independent improve- 
1- i-^df^ in the same mac)ttiie, and ti patent 

i- r them in the aggregate, the patentee 

is (.....: > recover si^aintt any iierson who fthali 

UM any one cf the im prove men ts so psUrnted, not- 
Wttlislancling there shall bare been no vioUtian of 
Ifce other itn prove men ts. — Hemedy for InfrtHgt' 
w u mt* The rcmediei for infringemeal. in England, 
ATR by mn artion at law for tbo damages, or by pro- 
cveiinga in equity for an injunction and account.-^ 
The remedy sought in erjuity ia for instant relief, 
•nd it is i)ftcn preferable to proceed in equity be- 
lore a »uil ia commenced at law. In the United 
Slate* of America, the circuit coart has original 
OOgnuaticr, a» well in equity as at law, in regard to 
^Ceat*. and may ^rant injanctions. The dmnagea 
for a breach uf the patent rigbt, in the United 
SiaCn of America, are three times the actual dama^rc 
■■feiiiMd by the patentee : the jury are to And 
-i •»-^- rfAQiRges, tlic court are to treble them. In 
Lhe patentee, in case of infringement, ahall 
' the damage he may austain, and a penalty 
for tiie benefit of the poor, not to exceed 3000 
Craac*. eod double in cue of second offence. — 
S*yral. If a patent be roid, ia England, tbe king 
mvf bare a acire facias to repeal his own grant. 
AU pcreooi are injured by the eiiatence of an ille- 
)ri iMlcitt fur aa inveutiuu. aud every one is 
Ikenrfbrc entiUed to petition far a Metre facias to 
haw it canoeUed. Paients are repealed, in the 
United 8tatea of America, by a process in tbe 
of a fctre faeiat.—~ WAo may obtain a Patent. 
who have resided two years in the United 
of America are allowed to obuiin patents tin< 
darllia tot of IttOO, on their making oath that tbe 
iatentioti bos nut, to the beat of their knowledge or 
bvlief, Uma used in any country before. The Cng> 
liih law has no restrictions on this bead, and it is 
every diiy's practice to grant patents fur new inveo- 
ii4i*n fn Amr-ricaa* and other foreigners. 

tig [wrtion of this article is modified 
TcelLent article m the " Popular En- 
(jdoptrUii i and wbst followH from the " Com- 
IKioo to the .UmaoRC," fur 183G. 

Am Act has been passed in a Ute Session of Par- 

Baiflit to do tway with some of the defects with 

Vttdk o«r aaciquated Patent Laws are encumbered ; 

iail*altbough it does not pretend to an entire re- 

mnvsJ of tbe causei of complaint, yet, considering 

Mittrd diAiculties of tbe cose, and the very 

•liable iiAture of some of the former propDsi- 

- -^- i.ndmcnt, we are not sorry that the 

vemrnt has been begun with caution; 

--...- umc wc wish to consider what has been 

>'y aa a begiiming, and hope it will lead the 

> grneral amelioration. 

; reet Krirvance of the system, was the de- 

:i of all right to a patent which reiulted from 

:C claim pat in to any part of an in> 

' might nut actually be new, although ^ 

uioaiiioce should be unknown to the in. 

iod ereo althongh the part claimed should 

.11 :ittd unessential portion uf tbe whole in- 

this matter clear, it must be 

luing tUc nature vf oo ioveauoa, 




such as a inschlne for instance, the patentee is 
compelled to describe the construction of his inven- 
tion in the fullest detail, so as to enable an ordinary 
workman to con&truct a similar machine. As, in 
every such new invention, certain parts mutit also 
necessarily be well known, certain whccltf and levers 
will be like wheels and levers in other machines; — 
and as to these wheels and levers the patentee can 
have no rictusive riglit, he is eipected to declare 
in his specification what parts of the machine he 
claims an his own invention. To these alone be 
baa rjEclusivc right ; all other parts are pubUc pro- 
perty, and may be used by any one. Tbua far all 
IS rigbt ; if it were otherwise, a patentee mij;ht be 
allowed a right to what is not his own. Tbe grier* 
ance complsined of is, that if a patentee should in- 
advertently lay claim to any port of bis new inven- 
tion, which part might afterwords be found not 
original, tie lust not only his right to an exclusive 
use of that one part, but to tlie entire invention, 
however new it might be. He was thus cooped up 
in a dilcjuma ; if he did not cUlm the whole of hU 
invention, from a fear of overdaiming, he of course 
lost his right to that which he did not claim ; if, on 
tbe contrary, he claimed all which was his own, and 
it should be found that some part was not original, 
then he lust his whole patent. Tlie Bi:>tive to thu 
severity seems to have been the wish to prevent, by 
■ penalty, an unprincipled schemer from endea- 
vouring to appropriate to himself more than bis 
own. But while tbe schemer was punished, the 
honest inventor was often a sufferer. A new ma- 
chine might have great merit, It might in principle 
and action be perfectly new ; but some of its details 
might huve bei^n used in souie other machine now 
in disuse, quite unknown to the inventor. This is 
discovered by some rival manufacturer, and the 
patentee loses his right. Oy the act now passed, 
this grievance is done away with ; if a patentee 
should be in the situation supposed, if be shoold 
find that seme portion of hi.t invention has beea 
aniiripnted, he may now, on a proper representa- 
tion, uljtHin Irjve to enter and enrol a disclaitner of 
such portion, and remain in the situation he would 
have been in, had no such claim ever been put for- 
ward. 

It has been objected to dua olteraUon, that ad- 
rantage may be taken of it by a dishonest schemer, 
who may take out a patent for an invention not hie 
own, and then, as he tiad< himself discovered, enter 
a diiK-'laimer, finit to one part and then to another, 
aa such parts are objected to, and in the mean time 
reap all the advantage of his patent, aa though tbe 
invention were Ins own. This, we imagine, is an 
impossible occurrence : it must be remembered that 
tbe enrolment of the disclaimer is not a matter of 
right, that it may be refused by the Attorney. 
General, unless a sutficlcnt cause is alleged for the 
alteration, aud that, in cause of fraud, it would un- 
doubtedly be refttsed. There is also aoother check, 
and a strong oue, against such a practice ; tlio dia- 
claimer cannot be rei'cived in evidence, in cose of 
an action brought before such diaclsimer was eo 
rolled. A patentee, therefore, who should make 
an overclaim, and against whom an action ahonld 
be brought in conAcqucuce of that OTcrcUim, wilt, 
as far aa that acliuu goes, stand precisely in the 
situation he would have stood in before the new act 
was passed. He will be liable to the same penal- 
ties, and be put to the same expense in the suit. — 
The only diffLrence ia. that he will be enabled to 
protect hiuuoU' from the loss of his wlwle pateul iu 



124 



MAGAZINE OF SCIENCE. 




•ucb a catif, anJ will stand U}K)n his own rigbl in 
future. Now, un honest pateiitrc will, it iji Inir, 
Fiiffrr in the imnivdiiite action the pennlty of hta 
iriudvertcnrt, but no more. The dishonoit one will 
render himeelf linble to the tnme [icuuhy, as often 
u he ahtill attrmpt to make mo of uny right giren 
him hy a frtiiidulrnt cUiim. 

Tlie Kcond clause enacts, that If a patentee ah&U 
hhvc re-produced some old invention, believing 
himEelfto be the in»entor, it %hit\\ be in the power 
of the crown, upon a rccommendnllon of Ibe 
Jndicinl Committee of the Pnvy Council, to con- 
tinue the pQ^ent to the patentee, wherever it shall 
uppear Uiat tfae tOTeution has not hem publicly aod 
Erttierallj used. It is feared by aoue persona that 
all kinds of old inrentions will be brought up again 
and prDmul8;atrd as oen-, under favor of this clanse, 
and that every body will be taking out patents for 
old and abandoned projects. Tbts appears very 
absurd. To my notliiiig of tlie cTprnee of taking 
out patents, and the olmoet certainty of their brin^ 
useleia to the pafenlec (fur we may be well assured 
that in ninrty-nino cases out of a hundred the in> 
ventions would not hare been abandoned if they bad 
not br<fn useltas), there are au many checks againat 
the coutiniiant^o of soeb patent by the crown to any 
but a itonS fide re-inventor, that few persons wiU 
feci inclined to rake out old books for the purpose 
of picking up lost Inrentions. If any person should 
be lucky enough to re- produce an invention of value 
abandoned from any cause, and generally forgotten, 
we see no harm in his having the monopoly of its 
me for a few years aa a recompense for his briuging 
to light a valuable idea, though we would rather he 
should be eolitled to it without any mlsrepreKenta- 
tion. 

The third clanse contains a provision against the 
rrpentrd vexatious actions by which a patentee 
might be put to enormous law expenses under the 
former act. Before the pfl.isiug of the new law, 
llthough an nction respecting the validity of u patent 
light be decided in favor of the holder of Che pa- 
tent, this verdict was no bar to a future action, nor 
to any niimber of fiitnre actions. Although nothing 
new could be alleged, although it was but going 
over the same ground nguin and again, the patentee 
might be compelled year after year to defend him- 
self against fresh actions to hii great injury, perhaps 
to bis ruin. Tlie cJause enacts, that in any action 
respecting the validity of a patent, if a verdict pa»f 
in ravor of a patentee, the certiticnte of the judge 
who tried the action may be adduced in evidence on 
any future action ; and if the verdict in sueh snb- 
aequciit actiuii be given in favor of the patentee, he 
shall receive treble costa. 

By the fourth clause, an extension of the tenn of 
a paletit, not exceeding etten years, may be granted 
by hii Majeety, on a recommendation of tfae Judicial 
Committee of the Privy Council, who muy call and 
examine witnr«srs in the cjise of n petitinu fur ex- 
tension. This i5 decidedly an improvrnient ; the 
term of fourteen years granted indiscriminately by 
every patent, is too short in Rome cases to render 
any profit to an inventor, and this chiefly in thoM 
invculiuns of great value whieh require lime to ia- 
iroduor. We mity instance Witt's improvements 
oti the steam engine, which, from prtjudic'? aud 
other caoftt^, nne hardly in general use wli'ju the 
term granted by ttis patent had trajiirtd. By the old 
act, nu cileiiicinn could be obtained irithout nn uf- 
plication to I'drliament, which was attended with so 
many difficulties ibat it has been rarely resorted to. 



The fifth and sixth clsuses refer to the manner of 

rniiduetiiig trials for Infringetutsnt of ; -^bt*» 

an<i regulate the coiita in hucU a' : Ut4 

elauir triHiots a penalty upon any \.^^....:. , numg 
the name or mark of a putcutee apoa any artkiv 
vrithout his permission. 

Here follows a more detailed abr, : 'J»b 

act. An Act to mnend the Lmi> ' ''err 

pQtfni for InvmtiOHM. [5 and 6 \* lil. i^ . c <**, 
—10th September, 1835.] 

1. UcCTting that it is espedieni to make certain 
additions to, nnil altcrnlions in, the present law 
touching letters patent for invenaions, as well far 
the better protecting of patentees in their ngbta. aa 
for the more ample benefit of the public : eoaeoa 
that any perfon having obtained letters patnjt (or 
miy invention, may enter frith the clerk of the pa- 
tents of England, Scotland, ur Ireland, reapectivcly. 
as the case may be, having first obtained the laa«» 
of bis Majesty's attorney-gcnerDl or solicilor^Mio* 
rat in cose of an Engltoh fratent, of the lord adm- 
cate or solicilor-gencml uf Scotland in the caae 6t 
a Scotch pntL-nt, or of hia Majesty's attomey-g^w> 
ral or eolici tor-general for Ireland in the caae ol an 
Irish patent, certified by his fiat and signature, a 
disclaimer of any part of his apecifboation. or a me- 
morandum of any alteration therein, out being sunb 
as iihiill rxtrnd the exclusive n^ht granted by tkfl 
said letters patent ; and which, when filed, ahali \m 
deemed part of such tpecUication -, but a caveaK 
may be entered as heretofore ; and such disclainar 
shall not affect aetions peoding at tha timo ; ad 
the a ttoniey -general may require the party to ad- 
vertiae his disclaimer. 

2. Where a patentee is proved not to be the real 
inventor, though he believed himaelf to be so, hfl 
may petition his Msjesty in couocil to confinn Id* 
letters patent or grant new ones ; and the aaiU peti- 
tion aIiqII be heard before the jtidicial oommi(t<« of 
the privy cuuncil, who, on being satisfied that tuck 
patentee believed himself to be the firaC aod original 
inventor, and that such invention had not bvcn 
generally used before the date of such first le:trn 
patent, may report their ojijnion that ihc prsyrr uf 
mch )>etitinn ought to be complied with, when-upoa 
hii Majesty may, if he think fit, grant such praysri 
but any person opposing such petition shall be en* 
titled to be heard before the said jodidatcommiiier s 
and any person, party to any former miC touclu^g 
such 6rxt ktlers patent, shall have notice of s«ib 
petition. 

3. If, in any action or soil, a verdict or 
shall pass for the patentee, the jadge may 
ceriificate, which being given in cvidano* in ^of 
other suit, shtiil entitle the patentee, opoa ■ variirt 
in his fnvor. to receive tieble costa. 

4. AUuwi H patentee, on advertising aa Ifaenftt 
mentioned, to opply to the privy council for a pn»« 
longed term. If the judicial coramittca report in 
his finor, bis term laity be prolonged fur sewO 
years ; but such application must be made be&ir« 
the expiration of the original term, 

A. In ease of nction, &:c.. ootice of objections to 
be given with the pleadings. 

G. Costs in actions for infringing letters patent; 
to be given as either party has succeeded or fail*:*! 
in any part of his case, without regard to the (*• 
ucrj remit of llie trial. 

7. Penalty for utting, unauthorised, the name or 
device of a pitentee, Aco., j£:AO. one half Co tot 
Mnjesty, ami the other to any in/urnier. 

Mr. Porcy, who hits hiul much experieftoe io fl^ 



MAGAZINE OF SCIENCE. 



123 



takinx of patenti. •tatn, that the 

of a patent for KiigUnd, iuh; bs 

'12U; for Scotland, at i.100; «iid 

n 2b. 

COINS AND MED.VLS. 

tarit l«(cly drlitercd before the Society of 

Wj^oTi described our prc&cnt mode uf en- 

kd muluplyiug the dies. 

■cliou uf tlie best iteel for tlie parpoNe* 

Tory imporuiuc, nnd not tiitfu'ifiitly 

[at Ml Will Tba MTT 6nL*etrcl tlint fijrina 

■ gnv«n and other rtiltittf; instruDiuatA, ta 

lUc purjiuse. fur unlc«s Uurdeiicd wtth great 

i* iciy Imble to trtck. Tlie vety euiir»u 

objectionable, as it ttc<|uirra fisjiurea 

difl presi. The object therefore n, to 

il of ■ medium qualttr — but the bc»t steel 

I* by want of ekill in the amUU who 

[b die ia brx^ught to a table in the 

lAfter being soflened, the engraver com- 

)Sm labora, by working out the dc?ice with 

tools in intsglio (sunk in), and when be 

fled bis work, the die id ready for harden- 

is, iu itself, a very ainiple process— but 

is often Btttfuded witlt aerioiia di^appolnc- 

Cttgravor, for it not unfrequcDtly bap- 

the labor uf many montJiB u cither in- 

Qltcrly destroyed, from the steel itself 

cy or heated to exceai. But Buppoiinff 

tl die, ur, as it is technically called, a 

be uninjured by tlie process of hardening, 

lur the purpose of furniihing a pun- 

s Steel impression in relief). For thif 

tk of soft Steel is turned Hat at the 

ly conical at the top. In this 

kl Hurface is cunipreaed into the ms- 

Uuw from the mulciptyiug die press : this 

Uic commencement of en impression, 

i«s so hard by compression, as to 

It annealing and rc>strikitig before it 

An impression taken iu this way la 

sutfiheoQ. vrhicb, when tJie oniirarer has 

■It tbfi deUcauy of finish existing in the 

ift then hardened, and serves for the pur- 

dics for coininK. by a eimilar process, 

tg Ike hardened steel into that whioh 

tinclioiii said Mr. Wyon, between striking 
)d coins, IB very esaential, so much to, ttittC 
aayiBg a few words on the subject. 
ly engraved in high relief, like those 
rias, and it requires a succession of 
forty or fifty, with repeated an- 
Lc ■ perfect ionpression. A modem 
contrary, is usuiilly brought up with 
kongh with the disudTsntage of the 
irder. Slandnrd gtild, for iuttancCf 
StwcJI^h of alloy : medals are usuelly 
ifold ; thi? rngriving u^ton the coin is 
tnade with a RUitablc degree of relief, 
a coin or mtdal, the lateral spread of 
;h would otherwise ooze out, as ii 
ircn the dies, is prevented by the ap- 
KsirclcoUar. acouiatcly turned to tli? 
!tbedics. The number of pieces wbiob 
by ooe pair of dies, not unfrrijuently 
three and four hundrt^d tbou- 
««cnige amount is much lf»s. Mr. 
, Ifaat be remembered instances of 
datroy«d in one d^y, owing tu 



tbfl diSertsnt tioalitiea of steel, and to the casualtifs 
to which dies are liable. There are. It appears, 
eight presses in the coining-room of the Mint, and 
he considers that the destructiun of one puir ol dits 
for each press per day, is a very fsir proportion! 
though it IS generally rather mors. 

It must be remembered, that each press prddaiva 
sixty pieces per minute, without reckoning stop* 
puei oooaaioDed by cbaogiug of dies and other con* 
tingences ; und Mr. Wyon remarked, that in 1817. 
the dally produce of coins, in half-cruwits, shilhogs, 
and sikpeoces, amounted to the enormous quantity of 
343,«>U0 per day fur tliree months : at that time all 
the clj;ht preucs were employed; but, on the lat of 
April. 18;j2, there wrrc 126, UUU pitces coined with 
tivc prcasti only. Prom the 4th of June. 1817, tu 
the 3Ut of December, 1333, tbete nere coined in 
Bovereignsand half sovereigns, 52, lB7(2ti5/. stcrliug* 



CAUTION TO EXPERIMENTERS WITH 
THE ELECTRIC KITE. 
Tn8 following excellent rcmarics on the msnagement 
of the electric kite are by the well-known and excrU 
lent rlcctricisn, Mr. Sturgeon, who, perhaps, has 
bad more practical experience in electrical monipu- 
lution than any person living. The remurks also uu 
the electric kite by the Editor in the early part of 
Vol. 1. of this Magulne will be read by the tyro 
with interest. Mr. Sturgeon says : — 

*' I repaired to the Artillery Barrack grounds with 
an electric kite, and in a ven* short time got it afloat, 
letting out string through the hands bum a coil or 
clue which was thrown on thegruund. Wbon aboni 
a hundred yards of the striug had been let out, s Ire- 
mcudoua discharge took ploce, which gave mc sticb 
a blow in the chest and lejcs that I became completely 
Btunued, let go the Btring, and coa8e<iuentiy tho 
kite •oon fell. 

The accident was owing entirely to my own neg- 
lect, and could not powtlbly have happened had I 
taken the following precaution : — 

Let all the string intended to be employed be first 
taken 00'the reel or coil, and stretched on the ground. 
Let now tbe iusnlating cord, ribbon, glass, or what- 
ever is used for this purpose, be attached to the kite- 
string and fastened to a peg, tree, or anything in- 
tended to bold the kite during the time it is up. 
Nfjct fasten the kite to the other end of the string, 
and let it ascend from the huod. 

Thia is the manner in which 1 nsoally proceed 
when heavy clouds ere hovering about, and ought 
always to be attei>dcd to, altliuugh 1 tiegli-cted it ou 
on this occasion. The exjK:rimenter by this means 
is completely out of dang-^r ; and he may easily 
ascertain if tho atring be highly charged by going to 
the other end, because of the brushes of light, and 
noiae attending them. 

1 liud it conveuient to have a eliding copper wire 
on the ulken cord, which can be moved, by means 
of a long glass rod, to any retjuired distaDce firom 
the wired string, the other end being stuck fast in tba 
groand. If the electric Are strikes two inches over 
the dry silken cord, (and it will sometimes strike a 
yard,) it would not be ssfe to ipproach it ; and no 
man could hold the string when it alnkes over one 
inch uf the nlk, or, which is the same thieg. tbroDgh 
Iht? nir. 

After tbe electrical state of the atring has been 

ascertained, tlie wire may be sliJed away from it ai 

fnras pouibte (tbe sUk ought never to be less than two 

yardK long). 'J'be other end is then to be taken uut 

' uf the gronud oud ettaobed to the appantua for ex- 



tS6 



MAGAZINE OF SCIENCE. 



periment. Tlie wire is a^^ain slided up to Che wired 
string^, and left there during the time the experi- 
mmts ure carryini^ on. 

The only method of gflttng the kite down during 
an intrrtse electrization of the string, with safety to 
the experimenter, is to unfuten ttie BUken eord from 
it« hold and let all gn : the kite fsila. 1 have fre. 
quently been annoyed, whilHt holding (he kite-string 
during hot bazy days when no ctuud was visible, by 
ft rapid succession of dbcharges, from which 1 had 
DO other means of escape than by quitting the string 
utd letting the kite fall. The same thing sometiniea 
happens in cold dense fogs in the winter. I have 
eiperienced these rattling or Lrricalous shocks when 
the kite has not been more than 30 yards from the 
ground, and the wired string at the same time 
touching it. Hence great quaoticies of the fluid 
must necessarily pass into the ground directly 
through the wire, in addition to that which pro- 
duced the shocks. 

The publication of these particulars may possibly 
previ^nt some ioexpcriuuced electrician from receiv- 
ing a death-blow from his kite-string. 

Young persons who sire fond of kite-flying should 
nliio be cautious not to have tlurir kites up during 
thander storms, as it is poraihle that a wet string 
may transmit a violent discharge, from which ft 
serious accident might occur.*' 

MAKING ARTIFICIAL EYES FOR 
ANIMALS. 
Mticii of the character and expression of animals 
depends upon their eyes: it will, therefore, be evi- 
dent that great attention is necessary in the arti- 
ficial imitation of these. 

The instruments necessary for making these are 
enameller's table, bellows, lamp, round pincers 
about six inches in length, which are closed by 
means of a ring, and witb which is held the iron- 
wire forming the support, and the base of these eyes, 
which it is impossible to blow. Procure anuthor 
flat pair of pincers of the same length, which air 
used for hendjing the enamel, as also for stirring up 
the lamp. These instruments can be had ready 
made in every hardware shofi. 

The materials from which the eyes themseltes 
are formed is an osrartment of cyliodera of enamel 
of all colors, which can be purchased ; besides some 
fragments or clippings of mirror-glass, which are 
melted in the lamp into a kind of cylinder like the 
enamel, so that they may be ready for use when 
required. During tlic process of melting these 
pieces of glass, considerable attention is necessary to 
free them from spots and globules of air. These 
cylinders can be procured ready made in the shops ; 
and at various gloss-manufactories. 

The table is placed in a situation where the light 
of day cannot reach it, as the double light would 
distract the vision during tlio operation. 

After the lamp has been lighted, the pipe of the 
bellows is directed towards the middle of the wick, 
which is slightly scattered in that part so as to pro- 
care ■ clear light-bluish flame, which is necessary 
Co secure success in the operation, because if it is 
not clear, the colors of the enamel arc liable to 
oliange during the operation of making the eyes. 
The vnomel which wo wish to melt shoutd be ap- 
plied to the extremity of the jet of the tlaroe, which 
St will not bum, and often melts more easily than in 
the centre. 

As small eyes are less difficult than large ones, 
it will be adviftable to coumeuce with them until we 



lidcsaft 

onB 



shall have acquired practice. VoT smatt 
small iron-wire ir uied about an inch and 
long, one end of which is bcld iit tlieroiuid | 
and the ntht:r is approached lo tbc fire, tow. 
cxiKJsed at the same time the rnamel of the 
we wish the eye, whilst the other is turned 
the lingers until it begins to melt. The q 
necessary for the sise of the eye is then faai 
the end of the irun-wirr. This by being to 
the tlnmc forms a small globe, and when it is 
ciently rounded, a little spe^rk of block ens: 
placed in the centre, for the purpose of iiailotnig 
the pupil. It is again exposed to the flsme that tba 
pupU may be blended into the mass. When it im 
properly incnisted. some glass is put upon It, 
which shoald extend three quarters across thu hv> 
misphere of the eye. This glass is intended to rr- 
present thr vitreous humour of the eye, and from 
which all its brilliancy proceeds. The eye is sUU 
expu^ed to the flame until the gla$s bos c^itcndsd 
over ttiat part of the eye which is intended for the 
iris; when we etfect this, it is allowed to oeot 
slowly. This kind of eye is made hf joining artc- 
ral pieces of iron -wire together, which rendem it 
easier to make them all uniform in point of sik*' 
because the first bring close to onr eyes guides ■• 
in the formation of the others. 

Secamd Method q/* Makinrj Epe*. — .Another 
thod of making eyes is the following : — Some 
of iron-wire, from three to four inches Ion, 
prepared, which have been well burned, 
strength must be prnportinned to the size 
eye which is intended to be made. These are 
curved in the midtlle over a tube of gUua 
or any other cylindrical and polished body: the 
trvmitief of each wire are united by twisCin^ 
over the other, so that they perfectly fit the sub- 
stance which they embrace. It is this drde fomcd 
by the wire which mokes the diomeler of the eyo, 
and the wire thus prepared is in the form of a 
rocket. The handle of this meket is fixed into tha 
round jiineers, and the head of it cunred by miking 
it parallel to that of the pinrcrs. This cin:U to 
filled with common enamel, of the color which m 
wish, extending it from the circumference to th« 
centre, and when it is nearly the thickness of Um 
wire, it is prevsed while yet in a state of fusion 
with the finl pincers, so that it may extend equally 
over the entire circumference. It is then put into 
the fire to couaulidate it. This hiding been done, 
the iris is formed by a drop of enamel of the pro- 
per color. This is heated and pressed oa befofv 
with the flnt pincers, and when it is inoorporalsd 
with the first enamel, the pupil is represented vMi 
small speck uf black enamel, as before mcntioneii. 
When this is melted and incnisted in the iris, botti 
are covered with gla»s, and heated again until sUths 
parts arc smoulb, and the glafs boa diffused itoslf 
over the whole iris. The eye is now placed nn 
some warm cinders, and left to ooot slowly, without 
which precaution it is liable to break ; or it may be 
put into worm water, and allowed to coot gradualty. 
It is then removed from the wire by loosening thv 
latter. This method is only adapted for eyes of s 
middling size. 

Third Method vf Mak'my ^ye*.— Tlierc is sltU 
another method of making eyef<, which is ]>rrhaf« 
better than those we have otready descrit>ed ; and 
that is, to blow them if we possibly con ; «hlrfa, 
however, connotbe done when they are stnall. Is 
this operation, a pipe of baked earth is used, or s 
tube uf ghus six or seven inches in Icogih, at the 



MAGAZINE OF SCIKNCE. 



127 



■bI of which t llttir white en«mel ii placed. Thit 
tl pUced ta the Aimv, so that tt may be blown. 
TbU {ormi a globe, whose dimensionR depend upon 
ibfl qnintitjr of air introduced. ^Iien thU globe Ji 
of the fixe wiihed. we place In the middle, and per- 
paodicuUrW to the point of lUe pipe, the quantit; 
of «Bstoe1 necessary to form the enunel. 7*he vecond 
MttDtl ia then incorporated with the 6nit, by pre- 
•enHo^ It to the flame, while attention is pnid in 
isra the pipe gradually round, »o that the I'nnmcl 
may difTuae itself cqunlly. and the irii be eiactly 
eirnalar. If it it rrquirrd that this iris should he 
of vmrioiu colors, like that of man for cxamplp, 
amall filaments of enamel are distributed in diverg- 
ing ray<t of Ihr luttable eolor ; the eye is then plticed 
in the tinme. until these have incorporated with the 
IT)*, afler which the pupil is placed as before 
tfifrirtrH. 

Dnnng (his operation, the globe is almost certain 
.Jo, , 111... down, partly from the air escitpini^, pnrtly 
heat, and from the pressure which is used 
;jn; the diflerent substancfi : air must iigain 
-■d from time to time to prevent it from 
!•* form. This becomes particnlarly necea- 
nry '^Ijlmi rIsss is applied, and when it is extended 
over the whole surface of the iria. 
The eyp hsTing got Its form and tHe. the pipe is 
n away. To effprt this, nf\er the air fans btn-n 
dii(!ed, the entrance of the pipe is stopped with 
r, and the back part of the eye exposed to 
: <- ; when the air contained in the globe and 
rucAeJ hy the pipe, comes through at the place 
«4kere the flame has moat action. This opeaing ia 
f^r* ' turning the point of the flat pincers, 

iy '■, all round the pipe; one point only 

is u,^ ., .....L'h the eye rcmuins 6xed, It is tiien 
wsrmed equally all over, after which it ia exposed 
to I gentle heat, and whea it ngain cooU, it ia sepa- 
rated from the pipe. 




PALINGENESY. 

t ymm fiaanam't Afathrmatiriil Itrrrvntioni. t 

PiTT^CK.SMST is a chemical operation, hy means of 
t pbuit, or an animal, as some pretend, ran 
d from its ashes. This, if true, would no 
ocmot be one of the oobtcs t secrets of chemwttry and 
lUcwophy. If »orae authors are to be credited, 
meral learned men of the 17th century were in 
pOMsftsinn of it ; but at present, as this pretended 
•wrtt, m consequence of the great progress made 
la chemistry, ia conaidered as a mere chimera, we 
iMl here confine ourftelves to examining the foun- 
ixioQ of tho«e principlea which have induced some 
mpuuble authors, such as the Ahbv Vallemont 
mi otbcn, to believe iu the possibility uf lhii>> 



Accordtog to the honest Abbe, nothing is simpler 
tad KMUMit to be cxplnined. We are indeed told, 
aaya be, by Father Kirchcr, tttat the seminal virtue 
of «Kb misturs is contained in it< salts, and these 
asit* onalterable by their nature, when put in mo- 
tieat rise in the vessel through the liquor in 
L-y are diffused. Being then at liberty to 
». ' *'-— selves at pleasure, they place them- 

•rl order in nhioh they would be placed 

b> ■( vegetatiuu, or the aame as they oc- 

<bi :be body, to which they belonged, had 

b«' >ed by the fire : in short, they form n 

fiUftl, wf « phantom of a plant, which has ■ perfect 
fUtwblaACc to the one destroyed. 



This reasoning is worthy of an aothor who couU 
believe that be who robs another of his money can 
exhale corpuscles different from thote exhaled by a 
man who carries his own. and thereby make the di- 
vining rod turn towftrd<i the placet where he has 
passed, ur remnined for some time. Does it not 
show great weakness to bclirve that the mere im- 
morality of an action can produce physical eflecCt? 
It would indeetl be otTering nn insult to our readers, 
to attempt to show the folly and absurdity of the 
above reasoning of the good Abbe, and of Father 
Kirrher. \jrt tis therefore only examine the facts 
which he relates. 

An English chemist, named Coxe. asserts tliat 
having extracted and dissolved the essential salts of 
fern, and then filtered the liquor, he observed, after 
leaving it at rest for five or six weeks, a vegetation 
of sm^l ferns adhering to the bottom of the vessel. 
The same chemist, having mixed northern potash 
with au eqanl quantity uf hbI ammoniac, saw soqw 
time after a small forest of pines, and other trees, 
with which be wsa not acquainted, rising from tho 
bottom of the vessel. 

The following fact is considered by the antlior as 
more conclusive. The celebrated Boyle, though 
not very favorable to palingenesy, relates, that 
having dissolved in water some verdigris, which. 
ns is well known, is produced by rombining copper 
with the acid of vinegar, and having caused this 
water to congeal by means of artificial cold, he ob- 
served at the anrface of the ice small figures, which 
had an fxact resemblance to vines. 

Notwithstanding these facts, and others quoted 
by the Abbe from Daniel Major, Hanneman, and 
various authors, if the partisan of palingenesy oa& 
produce none more conclusive, it must be confessed 
that they support their assertions by very we«k 
proofs. Every true chemist sees in these pheno- 
mena nothing but a simple ramified crystallization, 
which may be produced by different well known 
compositions; the most beautiful of these crystal- 
lisations, call improperly vegetations, are produced 
by the combination of bodies from tbe animal king- 
dom. 

The last experiment, relited by Itoyle, might 
occasion mure embarrassment; but as it is the only 
one, of a great many, made with the essential salta 
of a variety of plants, that inooeeded, there can be 
no doubt ihut ilie figures be MW were the mer* 
eflect of chanoe ; for how many other philosophera, 
who made the same attempt, saw nothing but what is 
exhibited by the surface of frozen wster, which some- 
times forms ramificationa exceedingly complex ^ 

Tho partisana of palingenesy however quote other 
authorities, to which they attach great importancr. 
We arc cold by Sir Kroelm Digby, on the authority 
of Qttercetan, physician to Henry IV, of France, 
that a I'ole showed twelve glass vessels hermetically 
scnled, each containing the aalts of different plants : 
that at first theae salts bod the appearance of ashes, 
but that when exposed to a gentle and moderate 
heat, tbe figure of the plant, ns a rose for example, 
if (he vessel contained tbe ashes of a roee, was ob- 
served gradually to rise np, and that as the vessel 
cooled the whnle disappeared. Sir Kenelm adda, 
that Father Kircher bad assured hint, that be per- 
formed tlie same experiment, and that he communi- 
cated to him the secret, but it never had succeeded. 
The story of this Pole i« relat&l by various other 
authors, luch as Bsry, in his Physique, and Guy do 
1& Brosse, in his bonk on the Nature of Pluitl. 
(To 6v crmtinufd ) 



128 



MAGAZINE OF SCIENCE. 



MISCELI^NEOUS EXPERIMENTS. 

The lltrre Ha/oes. — The fallowing experiment, 
which iiluttralra in a pleasinit; manner the actual 
formadoD ofbulcKiif , bubeen gWeu by Dr. Brewster : — 
Take a Batur.itcJ solution of alam, and having 
eprend a few dro)t]i of it over a pUte of glaas, it 
Kvili rapidly crysiallifte ia laiall flat octobedroiu, 
scarcely visible to the eye. Wfatrn this plate is held 
between tbs observrr and tliR ntin, or a candle, with 
the eje rcry close to the smooth side of the glass 
pittv, there will be Been three beautiful haloca of 
li^ht, ut different difltancea from the lumiuouabodj. 
The innermofti halo, which is the whitest, is formed 
by the iiunges refracted by a pair of faces of the 
iKfnhedral crystals, not mach incUnod to each 
other ; the second halo, which is more colored, 
with the blue t»j% ontwardit, ii formed by a pair of 
faces more inclined ; and the third halo, which ti 
very Urge and highly colored, is formed by a still 
more tnclinrd pair of fnoes. Each separate crystal 
forms three images of tho luroinoui body, placed at 
pointK 120'' distant from each other, in all the three 
linWs ; and aa the numeroDS small crystals huve 
tliclr refracting fuctf turned in every possible 
dirtrt-tiuii, the wliolt circumference of the haloes 
will lie completely hUed up. The same effects may 
he obtained with other crystals ; aud when they 
have the pro|«,'fty of doable refraction, each halo 
will be either doubted, when the double refraction^ 
ia considerable, or rvndertid brutuler, aud otherwise 
modifird in point of color, when the double re- 
fraction ia Email. The effects may be curionaly 
varied, by crystallising upon tlic same plate of glsat, 
crystals of a decided color, by wluoh mesas we 
should hare white and colored haloes sacoeediog 
«ftch other. 

7b obtain very targe Ornamental CrystaU. — ^To 
obtain largo artificial crystals of a regular shape, 
nN|uires conxidcrable adilrcjs, and mueh patient 
attentioa ; hut the result fully recompenses the 
double. The method of M. Lcblatic is as follows: — 
The salt to bo crystallised is to be dissolved in 
water, and evaporated to such a consistency that 
it shall crystallise on cooling. Set it by, and when 
<|tiitc cold, pour the liquid part off the mass of 
crystals at the bottom, and put it into a flat-bottomed 
vessel. Solitary ciyiitBls form at some distance 
from each other, nnii these may be observed gradually 
jocrrastng. Pick out the most regular of tliese, put 
them into a flat-bottomed vessel at some distance 
from each other, and ponr over them a quantity of 
liquid obtained in the same way, by e«-s|Kiratiug a 
•olotinn of the salt, till it cryslallises on cooling. 
Alter the position of every crystal, once at least 
every day, with a gloss rod, that all the faces may 
be allemattly exposed to the action of the liquid ; 
ior the hce on which the cryElol rests never receives 
any increase. By this process, the crystals gra- 
dually ioGrease in sixe. When they have act]uircd 
such a magniiude that Oieir forms can easily be 
dislinguifibed, tBe most regular are to be chosen, 
or those which have the c^act shape which we wish 
to obtain ; aud each of them is to be put separately 
into a vessel filled with a portion of the same liquid, 
And turned in tlie same manner several times n day. 
By this treatment, they may be obtained of aluiont 
any rise we think proper. Whenever it is observed 
that the angles and edges of the crystal become 
blunted, the liquid must immediately be poured otf. 



and a portion of ne^v liquid put in its place ; oUwr- 
wisc the crystal is infullihly d—*'-'-- ■ ■' 

7*0 Bieach Priuif and P> iple 

inimcrsiuD in oxygenated min .: thr 

article remain in it, a longer or shorter space of 
time, according to the strength of the liquor, will 
be sufficnent to nhiten an engra\ing : tf it 1>e n>- 
qaired to whiten the paper of n bound book, as it 
is necessary that all the leaves should be moiatemid 
by the acid, care must be t-nken to open the book 
well, and to make the boards rot on the «dg« of 
the vessel, in such a manner that the paper aloni; 
shall be dipped in the liquid ; the leaves must be 
separated from each other, in order that they may 
be equally moistened on both sides. The liquor 
assumes a yellow tint, and the paper becomea white 
in the same proportion ; at the end of two or three 
hourK, the hook may be taken from the acid liquor, 
and plunged into pure water with the nme eare and 
precaution as recommended in regard to the add 
liquor, that the water rnny touch both sides of each 
leaf. The water most be renewed every hour, to 
extract the acid remaining in the paper, and to dis- 
sipate the disagreeable smell. 

Beani\fui Oraammi for a Room. — Dissolw {■ 
seven ililferent tumblers, containing warm 
half ounces of sulphates of iron, copper, sine* 
alominei magnesia, and potass. Ponr them sll« 
when completely dissolved, into a large evaporating 
dish of Wedgwood's ware, and stir the whole with 
a glass rod ; place the dish in a warm place, where 
it cannot be affected by dust ; or where it may not 
be agitated. When due evaporation has takni 
place, the whole will b^in to shoot out into crystals. 
These will be tntcrsperaed in small groups, and sin- 
gle crystals amongst each otlier. Their color and 
pecnliar form of crystnlization, will disitinituish each 
crystal separately* and the whole together, remain- 
ing in the respective places where they were depo- 
sited, will display a very curious and pleasing ap* 
pearance. Preserve it carefully from dust. 

7^/je Ej-jihdinf/ liubbif, — If you take up a smftQ 
qiiaatity of melted glsKS with a tube (the bowl of S 
common tobacco pipe will do), and let a drop Ml 
Into a vessel of water, it will chill and condensB 
with a fine spiral toil, which being broken, the wbols 
substance will barst with a loud explosion, withoat 
injury either to the party tliat holds it, or him that 
breaks it ; but if the thick end is struck, rren with 
a hnrnmor, it will not break. 

Threp ObjficfM, dtMcernab/e rfw/y by the um* tf 
both Eyet. — If you fix three pieces of psper against 
the wall of a room, at equal di»lancc9, at the beigU 
of your eye, placing yourself dtrectly before them, 
at a few yards distance, and close your right cye» 
and look at them with your left, you will lee only 
two of them, sapixise the first and secoud ; altar 
the position of your eye, and you will see the nrst 
and third ; alter your position a second time, you 
will see tho second and third, but never the wbols 
three together ; by which it appears, that a pervon 
who has only one eye can never see three objects 
placed in this position, nor all the parts of one object 
of the same extent, without altering the situatioa 
of his eye, 

7*tro solid Metallic Alloyt, vAich mtlt, wkem 
ruLbetl toytiher. — Make an amalgam of bismuth. 
and on amalgam of lead, rub them together in » 
mortar, they will form s componnd which is nesrly^ 
as liquid as mercury. 



i»«iiM)M : — I'rlntvtl by D. Kiiasci*. 6, Wfijre llorw hanv. WiU- End,— PubU*li«l by W. UuTtAtii, II, Fatonioatei Bop. 
CuaviDLiiitcaUom, <iibtcii are afu^>cred Moutlily.) lu be aiUlrcssfd to Ihc Editor, at Z7, Collagu i>n>v«, MUa Cnd Roa*t 



AGAZINE OF SCIENCE, 



THE 



Sn9 ^ci}ool of ^rtg. 



•] 



SATUROAV, JULY 34, 1041. 



Hid. 







FRANKLIN'S AND FERGUSONS CLOCKS. 



XT II, 



130 



MAGAZINE OF SCIENCE. 



FRANKLIN'S AND FERGUSON'S 
CLOCKS. 

Air ingenioiu clock wu contrircd hj the late Dr. 
Franklin, of Philadelphia, that showed the lioure. 
minuttia, and secundif, with only three nheeli and 
two pinions in the whole movement. A description 
of which, wc think, will please sach of our readers 
aa are not acquainted with it, whicli we believe arc 
very few. 

The dial-plate of this clock ia represente<1 by 
Fig. 1. The houra are engraved in spiral places, 
aloog two diameters of a circle, containing four 
tiniea 60 minates. The index A goea round in four 
hours, and counta the minutes from any hour it baa 
pMied by to the next foUuwing hoars. The time as 
appears in the figure ia either 24 minute* piutt 3, 
or paat 7, or past 11 ; and so on in each quarter of 
the circle, pointing to the number of minutes sflcr 
the hours the index last left in ita notion. Now, 
as one can hardly be four hours mistaken in esti- 
mating Che time, he can alwoys tell the true hour 
and minute by looking at the clock, from the time 
he rises tilt the time he goes to bed. The Bmall 
hand B, in the arch at top, goes round once io a 
minute, and shows the seconds as in ■ common 
clock. 

Fig. 2 shows the wheel- work of (he clock. A is 
the Arst or great wheel ; it contains IGO teeth, goes 
rouad in four hours, and' the index A (Fig. 1) is 
put upon its aaiR, and moved round in the same 
time. The hole in the index ia round ; it is put 
tight upon the round end of the axia, so as to be 
carried by the motion of the wheel, bat may be set 
at any time to the proper hour and minute, without 
affecting either the wheel or its axis. This wheel of 
IGO teeth turns a pinion, B, of ten leaves ; aod as 
10 is but a sixteeuih psrtoflGU, the pinion goes 
round in a quarter of an hour. On the axis of this 
pinion Is the wheel C of 120 teeth; it also goes 
round in a minute ; for there are 16 minutes to a 
qturter of an hour, and 8 times 15 is 120. On the 
axis of this pinion is the second hand B. (Fig. 1) 
nod also the common wheel E, (Pig. 2) of 50 
teeth, for moving a pendulum (by pallets) that vi. 
brates seconds, as in a common clock. • 

This clock is not designed to he wound up by a 
winch, bat to be drawn up like a clock that goes 
only tliifty hours. Fur tliis purpose, the line must 
go over a pulley on the axis of tlie great wheel, as 
In a common thirty-hoar clock. 

One inconvenience attending this clock Is, that 
if a person wake in the night, and look at the clock, 
he may possibly be mistaken in the four hours, in 
reclcoDing the time by it, aa the hand cannot be upon 
any hour, or pasi: by any hour, without being upon, 
or passing by, four houra at the sninc time. In 
order, therefore, to avoid this inconvenience, the 
ingenious Mr. Fergiuon contrived the foUowiog 
method. 

In Fig. Z, the dial-pUte of such a dock is repre< 
seated; in which there is an opening A BC D, 
below the centre. Through this opening, part of a 
flit plate appears, on which the 12 hours are en- 
graved, and diviiled into quarters. This plate is ron- 
tiguoos to the back of the ditU-pUte, and turns round 
io 12 hours; so that the true hour or part thereof, 
appears in the middle of the opening, at the point 
of an index, F, which ia engraved on the face of the 
dial-pUte. G is the minute-haoil as in n common 
clock, going round through sll the CO minutes on 
the dial in an hour ; and in that time, the x>late 



m 



seen through the opening A B C D shifts oo« bo«r 
under the fixed, engraven index E. By these meaas 
the hour and mlonte may be always known at what- 
ever time the dial-plate is viewed. In this plate to 
another opening, EFGU, through which the 
secondi ar« seen on a flat moveable ring, almost ooo* 
tiguons to the back of the dioJ-plate, and as tha 
ring turns round, the seconds upon it are ahowa 
by the top point of a flear-de-Ua I, cugraved ott 
the face of the dial-plate. 

Fig. 4 represents the wheds and pinions in tfab 
clock. A is the first or great wheel; it contUBs 
120 teeth, and turns round in 12 hours. 0& in 
axis is the plate on which the 12 hours above-awa* 
tinned are engraved. This plate is not fixed oo tba 
axis, but is only put tight upon a round part thereof* 
so that any hour, or part of an hour, may be act Co 
the top of the fixed index A, (Fig. 3.) withoat 
affecting the motion of the wheel. For this par- 
pose, twelve small holes are drilled through the 
plate, one at each lioar, among the quarter dsvi- 
aiona : and by putting a pin into any hole to ▼!€«« 
the plate may be set. without affecting any pait of 
the wheel-work. This great wheel A, of 120 toaUf 
tumfi a pinion B, of ten leaves, round in an 
and the minute-hand L, Fig. 3. is on the 
tliia pinion, the end of the axia not being 
but round, that the minate-hand may b« turned 
occasionally upon it without affecting any part of 
the movement. On the axis of the pinion B is a 
wheel C of 120 teeth, taming round in an bonr, 
and turnings pinion D, of six leaves, in three mi- 
nutes ; for three minutes is ,a twentieth part of U 
hour, and six is a twentieth part of 120. Oa tiie 
axis of this pinion is a wbet:l E of 90 teeth, going 
round in three minutes, and keeping a pendulum 
in modoD that vibrates seconds, by pallets, aa in a 
common clock, where the pendulum- wheel has only 
30 teeth, and goes round in s minute. But aa ih^ 
wheel goes round only in three minutes, if it bo 
wonted to show the seconds, a thin plate must be 
divided into 3 times 60, or IRO equal partj. and 
numbered 10. 20, 30, 10, 50. GO ; 10, 20. 30. 10, 
50, GO ; 10, 20, 30, 40, 50, GO ; and fixed upon the 
same axis with the wheel of 90 toeth. so near the 
back of the dial-plate, as only to turn round without 
touching it : and these diriatons will show the se- 
conds through the opening E F G U in the dial- 
plate, as they slide gradually round below the ponal 
of the fixed fleur-de.lis I. 

As the great wheel A, and pulley on it* faxis, 
over which the cord goes, (as in a common thirty- 
hour clock,) turns round only once in twenty'tbvr 
hours, this dock will go a week with a cord of 
common length, and always have the true hour, or 
part uf that hour, in eight at the upper end of the 
fixed indpx A on the diaUplute. 

There are two advantages which Mr. Pergasott'c 
clock has beyond Ur. FrankUn's : hat it has two 
disadvsntages of which his clock is free. For in 
this, although the twelve-hour wheel turns the mi* 
nute index L, yet if that index be turned by liand to 
set it to the proper minute for any time, it will oot 
move the twelve-hour plate to set the correapondtog 
part of the hour even with the t/^p of the index J : 
and, therefore, after having set the minute index L 
right by hand, the hour-plate mukt be set right by 
means of a piu put into the small hole in the plate 
just below the hour. It is true there is no gteat 
disadvantnge In this ; hut the pendulum -wheel 
baring ninety teeth instead of the oommon nnuibvr 
thirty, may probably make some diflereitce to ths 



MAGAZINE OF SCIENCE. 



131 



It, 00 iK-oount of tJie imallnest of the teeth ; 
U ii tierlAin thAt it will cause the peud olu m ■ ball 
la ^Mcribe tml fltnAll arra ia ita vibratiDnii. Sooie 
■VB of acMniOT thiok nn&ll arcs are beat ; but where- 
k9t «e know doc. For whether the ball dearribes 
^jMf or wnail arc, if Che arc be nearly cycloidal, 
arill be performed in equal timea ; the 
ire will depend entirelj on the length of 
-rod, not on the Itrngth of tbc arc 
.dtaenbct. The lar^r Ihcarcu, the greater 
of the ball ; aad the greater the 
i», the less will the time of the vibra- 
■fftscte<d by any anef|aal impulse of the 
b1 npon the palleta. 
ofafcction to Mr. Fer!:uaon'i clock ia, 
of the flat ring on which the seconds 
U will load the pivota of the axis of the 
tridi a great deal of frietioQ, which 
yoMihln meana to be avoided ; and yet 
docka, reoeotly made, goes very well, 
ig tbe weight of this nng. This ob- 
rr. can easily bo remedied by leaving 
Mconds are of very little use in couitnoa 
udfl for astronomical observationa ; and 
ocver have them. 



ran 



CARTHAMUS. 

v»t or safflower (earihamn* timctoriutj t 

of which alone is used ia dyeing, ia an 

plattt coltirated io Spain, E^ypt, and the 

TSrPC are two varieties of it — one which 

t leaves, and the other smaller ones. It is 

vhich ia cultivated in Egypt, where it forms 

le article of commerce, 

cootaioa two coloring matters, one 
the other red. The first alone is soluble 
tta aolutioQ ia always turbid : with re- 
cslubica ib« characters usually remarked 
odoring matters. The acids render it 
aUcalics dtepen it, giving it more of an 
both produce a liLlIe dun precipitate, 
of which it becomes clearer. Alum 
pitxte of a deep yullow, in^smdll quiin* 
tolacioo of tin and tbe other meuUic 
predpitatea which have nothing re- 

ittcr of csrtbumus ia not employed ; 
Io extract tliis portiim, tiie cartbamus 
a bag, which ia trodden under water, 
ooioT can be prcased out. The flowers, 
yeUow, become reddish, and toac in this 
I ttsrly one half of their weight, la this 
trcascd. 

the red part of certhamos, and 
'9nipo§ it to stuff, the property which 
of dissoWing it ia bad rerourse to, 
ifterwartU precipitated by an acid. 

of dyeing cooaiats, therefore, in ex- 

eoloring matter by means of an alkali, 

iog it on Uie stoif by meani of ao acid. 

which aervea for making the rouge 

^ladies. 

Aa rouge, the solution of carthamus ia 

vsh cry«taUiaed carbonate of sodii, audit 

by lemOQ juice. It has been re- 

kmoUr beginning to spoil, were fitter 

Ma tboae which were less ripe, 

nnined much mucilage. After squees- 

*»nnti juice, it is left to settle for some 

>t4t£ of carthamua U dried at a 

j.tc« of fttuue-ware ; Crou which 



it is detached and very carefully ground with talc, 
which has been reduced to a very subtile {lowder, by 
means of tbe leaves of shave-grass ffqmnetum) ^ and 
snccessively passed through sieves of increasing fine- 
ness. It is the bneiiets of the talc, and the greater 
or less proportion which it boars to the carthamua 
precipitate, which constitute the difference betweea 
the high and low priced rouges. 

Carlhamua is used for dyeing silk, poppy, nwarat 
(a bright orange-red), cherry, rose color, and Heali 
color. The process dtficrs according to die intensity 
of the color, aud the greater or less tendency to 
flame color that is wanted. But tbe carthamus 
bath, whose application may be varied, is prepared 
as follows : — c 

Tbe carthamus. from which tbe yellow matter 
has been extracted, and whose lumps have been 
broken down, is put into a trough. It is repeatedljr 
sprinkled with cendresgravetces (cnide pearl ashes), 
or soda (barilla) well powdered and sifted at the 
rote of 6 pounds for 120 potinds of carthamus ; but 
soda is preferred, mixing carefully as the alkali ia 
introduced. This operation ia called amc*trer,— 
The amettrcd carthamus is pot into a small troogh 
with a grated bottom, first Unlng this trough with ■ 
closely woven cloth. ^Vhen it is about half fiUed« 
it a placed over the large trough, and cold water ia 
poured into the upper one, till the lower becomes 
full. The carthamus is then set over another trough, 
till the water comes from it almost colorless. A 
little more alkali is now mixed with it, and fresh 
water is passed through it. These operations ar« 
repeated till the carthamus is exhausted, when it 
turns yellow. 

After distributing the silk in hanka upon the 
rods, lemon juice, brought in casks from Provence, 
is poured into the bath till it becomes of a fine 
cherry color ; this is called turning the balb (viver 
le 6aiu). It is well stirred, and tbe silk m im. 
mersed and turned round the skein-sticks in tbe 
bath, as long as it is perceived to take up tbe color. 
For poneeau (poppy color), it is withdrawn, the 
liquor is rwi out of it upon the peg, and it is turned 
through a new bath, where it ia treated aa in the 
first. After this it is dried and passed through fresh 
batbs, continuing to wash and dry it betwe«;n each 
operation, till it baa acquired the depth of color 
thst is desired. When it has reached the proper 
point, a brightening is given it by turning it round 
the sticks seven or eight times in a bath of hot 
water, to which about half a pint of Icmon juice 
for each pailful of water has been added. 

When silk is to be dyed ponceau or poppy color, 
it must be previously boiled as for white ; it must 
then receive a alight foundation of annotto. as ex- 
plained in treating of this substance. Tbe silk should 
not bo alumed. 

Tlie ntcarate, and the deep cherry colors, are 
given precisely like the p<meeaiLX. only they re- 
ceive no annotto gronnd ; and batlis may be em- 
ployed which have served for Kht ponceau, so as to 
complete their exhaustion. Fresh baths are not 
made for the latter colors, artless there be no occa- 
sion for the poppy. 

With regard to tbe lighter chcrry-reds, rose color 
of all shades of flesh colors, ttiey are made with 
the second and last runnings of the carthamus, which 
are weaker. The deepest shades are passed through 
first. 

Tbe lightest of all these shades, which is an ex- 
tremely delicate flesh color, requires a lillle soap to 
be pat into the bath. This soop lightens tbe color. 



■ 
I 



i 
4 



J 



132 



MAG^VZINE OF SCIENCE, 



end prerenU it from Ukini^ too ipeedUy, and be- 
coming unevrn. Tbe lUk is then washrd. and « 
Uulc brightening iti giTcn it, iu n Ualh which hu 
Bcrfc4 for the dcepf r colors. 

AU these baths are rmplojed the moment thry 
sre made, or as ipeedily as ))Ofl«ibIe, becatue they 
lose much of their color upon kn'ping, by which 
thry arc cren entirely deatruyed at the end of q cer- 
tain time. Tliey ore, moreover, u«d cold, to pre- 
sent the color from being injured. It must hove 
been remarked in the ei}>erimentA just descritMd, 
that the csuntic alkaliRs attack the extremely deli- 
cato color of cartfaamus, making it pass to yellow, 
lliis is the reason why cryitslt of soda are pre- 
ferred to the alkaline matters. 

la order to diminish tbe expense of ttie cartha- 
mns, it is the prnctice in preparing the deeper 
shades to mingle witli the first and the second bath 
abont one-fifth of the bath of archil. 

Dobercincr regards the red (»Ioring matter of 
carthamua as an acid, aiid the yullovr as a base. — 
His carthamio acid forms, with the alkalies, color- 
ks* ults, decomposed by the tartaric and acetic 
adds, which precipitate the acid of a bright rose- 
nid. Hrjit has a remarkable inflarnce upon rar- 
Uiamns, rendering its red color yellow and dull. — 
Hence, the colder the water is by which it is ex- 
trocted. the finer is the color. Light destroys the 
color very rapidly, and hitherto no means have be«a 
found of counteracting this effect. For this reason 
this brilliant color mnst be dried in the ahadc, its 
dye must be given in a shady place, and the silk 
atuffs dyed with it mast be preserred as mnch as 
possible from the light. Age is nearly as Injarioua 
as light, rspecially upon the dye in a damp state. — 
He color is very dear, because a thousand parts of 
carthamua contain only five of it. 

In preparing the flnrst roage, the yellow coloring 
matter being separated by wssbing with water, the 
red is then dissolved by the aid of alkali, and ia 
thrown down on linen or cotton rags, by saturating 
ttte solution with vegetable aeld, Tbe color is hosed 
oat of thr^e rags, dissolved anew in alkalis, and 
once more precipitated by lemon juice. The best 
and freshr»t carthsraus mast be selected. It is put 
into linen bags, which are placed in a itream of 
water, and kneaded till the water rans off colorless. 
The bags are then put into water, soared with a 
little Tioegor, kneaded till the color is all expelled, 
and finally rinaed In running water. By this treat- 
ment the carthamua loses nearly half its weight. — 
6633 cwts. of sofllower were imported into the 
United Kingdom in 1835, of which 2930 cwU. were 
retained fur Internal consumption. 



ENGRAVING. 

Enoratino is understood to be the art of cutting 

the Kurface of wood, or smooth metal, so thai the 

lines formed may be coTcred or fiUai up with ink ; 

then being sobjccted to an oppropriste pressure, 

the ink shall he left nn the surfnce of the paper 

printed upon, forming whot is called an etching, a 

^Vood, copper, or steel cngrnTing, according to the 

material worked upon, or else the manner in which 

K work is executed. In the Utter sense. engrsTing 

primarily divided into three great acctioiu, each 

tally disliact from tne other. 

Engraving on wood, or wood engraving, in which 

Hnes are left even with the surface, the rest of Uie 

wwd b«u»g cut away ; thcM are printed at the 



common printing press, alone or attended with 
iy]ic, sach as illustrate this and other similar worktt* 
To dcM:ribc the mannrr of et^rhini; aud copper* 
plate engraving, in general terms, so that it may ba 
understood without entering into minate particidBrs, 
it may be said to be performed thus:— First, tho 
copper or other plsta ia covered evenly and thulT 
with a certain compositioii, called eiehing ffrtnam^ 
The design or drawing is then transferred to i(< 
then in the case of etching, the lines tbni smb 
on the ground, ore scratched with on etching needle^ 
so as to lay lure the aarCace nf the eopper benesih 
the ground : then, a waxy substance is made to 
adhere to the piste, so as to form a border arooad 
the picture, as it may be called, shout half an inck 
high ; the plate has then aji acid poured upon tt, 
which eats or corrodes away the exposed lines o( 
copper. 'When sufficiently corroded, the bordmuj 
wax is taken away, and the plate washed with opaila 
of turpentine, which removes the etching ground, 
sad ahuwa the cop|ier- plate, bright aa when first 
taken in hand, but with at least an outline, and ui 
most instances a drawing considerably shaded. U 
will be remarked that no tool whatever has beca aa 
yet nsrd, except a needle. This then, coostitatea 
an niching, which is merely a plate of metal widt 
lines corroded in it by means of an acid. Those 
etchings which are afterwards to be made iaCo 
engravings, ore bit in very faintly, but the linos vv 
afterwards cut deeper or wider, by a amatl tool» 
called a prefer, or burin. 

Etchings and engravings, having lines, or, tBKRfti 
cases, dots below the general surface, the printing it 
conducted as follows : — ^Tho whole plate is covoad 
with ink, and the surface then cleaned, leaving only 
the ink in the lines ; passing this through Hm 
coppcr-plste printer's rolling press, with a l^ijlft 
pressure, the paper adheres to and brings the ink- 
out of tlie lines, forming what is called ayiroq^tf 
of the best quality, and a yriiU, if of nvandatf 
value. The illustrative figures in the present NOb 
will give an idea of the difference between engravioig 
on wood and on metallic plates, altbuugh in this 
instance both are executed on wood. i^Thr. side-cula, 
and alao a port of the others, consist of lines i^, 
the rest of tbe wood being cut sway ; but in the 
clock faces, the general surface is left nnton 
and the lines only are cut away. The sa 
these is blackened with ink end printed 
copper-plate prinCiog, tlie letters, figures, and 
only would appear : thus, our leading rata 
the engraved plate or etching, and not a print 
from that plate. 

This being clearly understood, the next thiofl l». 
be considered are the requisite tools and 
and we would premise that tbe same are lued 
every style of metallic rngmving. modi6ed 
a trifling degree to suit the material to be 
or perhaps one or other of them may not be 
except in fwrticular cireumstanoea. 

Tbe only tools required, are a hand vice, a ami 
euihion, two or three ^orers of different sixea. ■ 
etching neeHU, a bumiahffr, a Merger, a rsdi^ 
with a straight edge, two /itch ptnciU^ or brutfm, 
(one QS small as possible, the other obont as large as 
a small goose-quill,) a dabber, an oi7 rvbber, aud a 
piece of Turkty ttone : and if mathematical or 
similar engravings ore to be executed, a case of thv 

* A Tall acMiUDi or ttio art ol Eny ravin( lo Wood, li glna 
In Vol. I. rutilitininit aiteicri^na ot the varinu* tociU. Ic« W* 
lber»tiire ili^ n.ii (alrod furutvr In allutV l<> thnt fArticuloi 
act, bul c«»Gmv uurvclvca al prt.'tent lo engravnig ua nwiai. 



MAGAZINE OF SCIENCE. 



133 



drawing InBtnimcnU mOAt be added. The 
misrUlc reqaired, arn »ht«U qf copper or tteei, 
lo mgrmvc upon, ftchuuj rfrounti^ hardering iriu*, 
«ttknir «eidt Brunxwick black vartiith, tpiritt qf 
tarp^ntine, a yjojr tnptr, come o//, and a fine piece 
of dear charcoai, with the bark scraped off, and 
en* end made stunotb. 

Hm aamdcuMhiun ia a flat leather bag, made in the 
fix^ inatvocQ like ibe two sidea of a leather cricket 
hall. It ia formed of sheep leather, and when the 
fidra are tewed together, leating bet a small hole in 
the Afving. it is filled with sand ; the sewing is then 
cocDpicied — tbe whole soakrd for a day in water, 
od then prraaed with a great weight, or in a acrew 
praaa, when it aunmea the flattened form, which it 
ralUiM afterwards. The sixe most convenient fur 
DM moat be according to the ai«e of the copper, 
to be engraved. The und cusUion is not re- 

io etching, its uc being to support the pUte 
itoadUr, and to allow it to be tamed round euilj 
wbcD being cot with the grarer, according tu the 
ri^irementA of the artist. 

Thm iuokd vice ia used to bold the plate b^ one 
■Orsor or edge, during tbe time it is heated and 
Mdk«d, aa afterwards to be described. It is auf- 
M l ll y large if yoa ran hold up the plate by it with 
mlnad three or four minutes when it is fastened 
mtlHcdge. 
" OrVffcn are small tools, formed of a handle, about 
n bch long, Bod a blade or cutting part, about 
} imdies long, such cutting part being formed of a 
loaeDgc-shaped piece of steel, ground to a bevelled 
edge. For audi gravers as are to cut thin lines, 
Ac bhule is narrow ; for others the bUde is ne4u-Iy 
•^fUre, arid the point eoniequently of a more ob. 
taw angle. For steel angmvings, the gravers are 
l«(]airrd lo be tempered harder than for copper. 
As aitv*dj remarked, gravers are not required in 

Nmtlle, Hching needJV, or dry point. — Thia useful 
teatran^ent may be compared to a round, fine-pointed 
ta*d awl, aet at the end of a handle, a quarter of on 
hefa tfatrk, and 4 or & inches long. An excollcnt 
■batltnle may be easily made by any person by 
tdjng a thick short needle, such as ia used by tailors 
mtl bcmparreisea, called a htuni, (No. 3 and No. 5 
Ant rtfprtipriateO »nJ inserting them into the end of 
« ooHmon pencil, so that it shall bo firmly fixed ; 
(fee poiat not projecting above a quarter of an inch. 
Whni one needle gets blunt, another is easily made 
lOTrpIncc it. Tbe use of the etching nt^edle is to 
KFstch throui;h tbe surface of the ground that the 
ovpper may be laid bare in places prpvious to bUiny 
^ B9».d «lio to scratch any faint lines on the copper 
• rw«rds, to throw in a shade or make a line, 
■2 dune with mnch less labor than with a 
mfcr. Jc is in tlte latter use that it ia called a 

A fcwwMAer.— This is a straight piece of §lee], 
^dvalty tapering to a point, and made everywhere 
pmtuAy imooth and bright. The use of it is im- 
^btA by the name ; it is to burnish or rub out lines 
made, or else to suflen down such iis 
bern made too deeply, and oonsoqucotly print 
too dark. 

ISie tcraper iaa triangular piece of steel, fastened 
l» « bAudlfl, ch« edges being ground sharp. The 
Ma of thit tool is to scrape out such parts as re- 
qoiffe lo be removed, and are to deep that the hur- 
ts not aufiuient to remove them. 

tt\t bt roniinvtd ) 



PALINGENESY. 

CSaumed/remt poffr 127, and conclwifd.) 

We are told by Kirober himself, in his " Ara Mig- 
netica," that he had a long-necked phial, hermeti- 
cally sealed, containing tbe ashes of a plant which be 
could revive at pleasure, by means of heat ; and that 
he showed this wonderful phenomenon to Christina, 
queen of SwL'dtrn, wbo was highly delighted with it; 
bat that having left this valuable curiuailjr une cold 
day in his window, it waa entirely destroyed by the 
frost. Fatlier Schott also asaerts, that he saw this 
chemical wonder, which according to his account, waa 
a rose revived from itsusbes; and he adds, that a 
certain prince having requested Kircher to make him 
one of the same kind, he chose rather to give up 
his own than to repeat the operation. 

The process, indeed, as taught by Kircher, is so 
complex and tedious, that it would require no imali 
patience to follow it. Father Schott relates it at 
full length, in his work entitled " Jocoseria Naturse 
et Artis," and he calls it the imperial secret, bcc^uso 
the Emperor Ferdinand purchased it from aohemist, 
who gave it to Kircher. 

This em[M:ror was exceedingly fortunate; for it 
was to bini that the philosopher, who had the 
secret of the pliilosopher's sloue, addressed himself, 
and gave a proof of his art by transmuting, aa ifl 
said, in his presence, three [touods of mercury into 
two pounds and a half of gold. 

We most however content ounelvee with point- 
ing out the phicca where the curious may find thia 
singular procuba ; for besides the length of the de- 
scription, nothing seems leas calculated to succeed. 
Digby, therefore, and many others who followed 
this method, did not obtain a favorable result ; and 
there KB reaaon to^ believe that their seal fur iialinge: 
neay would induce them to omit nothing that was 
likely to insure them success. 

Dobreaensky. of Negropont, has alto given « 
process for t!ie resurrection of phints. which seems 
to have been attended with not better aucvcas. We 
are at Icujit told by Father Schott, that the attempts 
of Father Conrad proved iuefiectoaJ, and he there- 
fore lapposea that Dobrezensky did not reveal all 
tlie circumstances ot the process^ but kept Che most 
important to himself. 

M^haC then can be sud in opposition to all these 
authorities ? Undoubtedly, the IMiah physidao 
was a quack, and we shall describe hereafter a 
method of prodociog a false paliugenray, which, if 
performed with art and in a prupL-r place, may im- 
pose on credulous persons. To be convinced that 
Dobrexenaky, of Negropont, was a mere impostcr, 
we^need only read the "Technica Curiosa," or the 
"Jocoaeria NatufE et Artis." of Father Schott; 
for he had the impudence tu pretend that he could 
pull out the eye of an animal, and in the course of 
a few hoars restore it, by means of a liquor, which 
he no doubt sold as a remedy fur sore eyes. He 
even tried it on a cock. A person who could assert 
such an impudent falsehood, in regard to one iset, 
would do the some in r^ard to anoUier. 

The authority of Father Schott will certainly be 
of little wt'ight with those wbo have read his works. 
In regard to the testimony of Kircher, we confess 
that we find some embarrassment : a Jesuit cer- 
tatnly would not wilfully hsffo told i falsehood. 
But KirchiT was a man of a warm imagination, pas- 
sionately fond of every thing singular and extraor- 
dinary, and wbo had a strong propensity to U-lieve 
to the monrcllous. What can bo expected from a 



134 



MAGA2INE OF SCIENCE. 



man of that character ? He often ihmkt he sees 
wbiit be iloet not tee, and if be deceives otheri he 
ii first deceired faimaetf. 

Some persoos go still farther, and assert that oh 
animal may be nnrived from its ashes. Father 
Scbott, in his ** Pbyslca Cariosa," eren gives the 
figure of a sparrow thoa revived in a bottle. GafTarel* 
ill his "Unheard of Cariosities/' beUeves in this 
fiftct, and coniiden it as a proof of the possibility of 
the general resurrection of bodies. This pretended 
revival, however, is a chimera, still more absurd 
than theformer; and which, at present, it would be 
ridiculous to attempt serioustj to rtifute. 

In short, what reasonable man can with Kircher 
believe, that if the ashes of a plant be scattered on 
the jp^ound, plants of the like kind will spring up 
from them, as he says he frequently ex|»erienced ? 
Wlio can admit as a truth, that if crabs be burut, 
and thcD distilled, according to a process given by 
Digby, there will be pruduccd in the liquor small 
crabs of the size of a grain of millet, which must be 
nonhshed with ox's blood, and then left to them- 
selves in some stream ? Yet we are told by Sir 
Keoelm that this he himself esperienced. It ii 
therefore impossible to clear him from the charge 
of imposture, unless we suppose that by some meana 
or other be was led into error. However, it ie cer- 
taiu that Digby, with great zeal and s considerable 
share of knowledge, had a strong propensity to all 
the viaiona of the occult and cabalistic sciences. 
In our opinion, he was one of those visionaries 
known under the name of Rosicnuiatu. 

An iUwtory kind of Paligenesy. — We have 
already mentioned a kind of sleight of hand, by 
means of which, credulous people might easily be 
imposed on, and induced to believe in the reality of 
p&lingenesy. We shall now discharge our promise 
by describiog ic 

Provide a double glass jar of a moderate size, 
that ii a vessel formed of two jars placed one vrithin 
the other, in such a nuniiar, that an interval of 
only a tine in diameter may bo Icit between Ibem. 
The vessol may be covered by en opaque lop or 
lid, so disposed, that bjr turning it in ditferent di- 
recCioDa,the inner jar may be raised from or brought 
nearer to the bottom of the exterior one. In Lbe 
interior jar, on a base represeotiDg a lieap of ashes, 
place the stem of an artificisl rose. Into the lower 
part ol the interval between the two jars introduce 
a certain quantity of sohes, or some solid sub^stance 
of a biiuihir appearance ; and let the remainder be 
filled with a composition made of one part of white 
wax, twelve parts of hog's lard, and one or two of 
oUrifted Unseed oil. .This oily compound, when 
cold, will entirely conceal the ingide of tlie jar ; but 
when brought near the fire, if done with dexterity. It 
will dissolve, and by shaking the lid, under a pretence 
of hastening the operation, the compound may be 
made to fall down into the bottom of the exterior 
jar. The rose in the interior one will then be seen ; 
■nd the credulous spectators, who must not be suf- 
fered (o approach too near, will be surprised and 
astonished. When you wish to make the rote dJB- 
appear, remove the jar from the fire, and by a new 
aleight of hand make tlie dissolved semi-tronspsrc^nt 
wax flow back into tlie interval between the jam. 
By accompanying this mancenvre with proper words, 
the gaping spcctaton will be more easily deceived, 
and will retire firmly jiersaaded that they have seen 
one of the moit curious pbeuomeoa tliat con be ex- 
hibited by the united efibrts of chemistry and phi- 
luMipby. 



ANALYSIS OF MINERAL WATERS. 

TnK examination of mineral waters with a new |« 
ascertain their ingredients, and thence their medical 
qualities and the meana of compounding them arti- 
ficially, is an objoct of eonsiderable importance to 
society. It ti, likewise, a subject which deatnw 
to be attended to, becaose it affords do mesa op* 
portunity for the agreeable practice of chemifld 
skill. But this investigation is more espedaUy of 
importance to the daily purposes of life, and the 
soccers of manufactures. It ronnot but be an m- 
tcreiting object, to ascertain the componrat parts 
and qualities of the waters daily consumed by tha. 
inhabitants of large towns and vicioitica. A. 
minute portion of unwholesome matter, daily 
may constitute the priadpal cause of the diffi 
in salubrity, which are observable io different placs. 
And with regard to manufactures, it it well knows 
to the brewer, the paper-maker, the bleacfaoTa Ul 
a variety of other artists, of how much oooseq^enot 
it is to them, that this fluid should either be pan, 
or at least not contaminated with such principles m 
tend to injure the qualities of the articles they makSb 
This analysis has accordingly employed the atCH^ 
tion of the first chemist. Bergmann has wrictaa 
an express treatise on the subject, which may b9 
found in the first volume of the EngUab tmntiUrina 
of his Essays. Kirwan published a valuable volu^t 
on the analysis of wateri. 

The topography of the place where these 
rise is the first thing to be cunsiderBd. By 
ing the ooze formed by them, and the 
itones through which they are strained and 
soma judgment mayjbe formed of their coni 
In filtering through the earth, and meaaden 
its Borfooe, they take with them particles of 
kinds, which their extreme attenustion rendera 
blc of being suspended in the fluid that 
their vehicle. Hence we shall sometunei 
these, water; siliceous, calcareous, or 
earth ; and, at other times, thoogfa less 
sulphur, mdgneflion earth, or, from the 
tion of carbonated iron, ochre. 

The investigation of mineral waters 

1, In the examination of thorn by the 

2. In the examination of them by reageats 
the analysis properly so calk'd. 

The exaniinution by the senses consists in 
ing the effect of the water as to appearaaoe, 
and taste. 

The appearance of the water, the instant in 
it is pumped out of the well, as well as after 
stood for some time, affords several indicationa, 
which we are enabled to form a judgment 
ing its contents, if the water be turbid at 
the BuhBtances sre suspended only, and 
solved ; 'but if the water be clear and 
at the well, and some time interreoea before 
comes turbid, the contents are dissolved 1^ 
of carbonic acid. 

The presence of this gas is likewise ind 
small bubblei, that rise from the bottom of 
and burst in tlie air while they are ma 
escape, though tlie water at the same time, 
hoB not an acid taste. This ia the case, 
to Count Razoumowiki, with respect to 
spring in Vallois, and the cold vitrioUted 
beate iprings at Aatracan. But the 
proof of n dpring containing carbonic acid 
generation of bubbles on the wster beiag 



MAGAZINE OF SCIENCE. 



135 



bunting vrith more or lets noise, while 

ent deposited by the water in the well 

t to be examined ; tf it be yellow, it indi- 

oe of Iron; if blftck, that of iron 

with vnipbur ; but chalybeate watera 

lom inlphurettcri. the latter occurs Tery 

is to the color of the water itself, there 

latanrea where ttiia can give atiy inilica- 

B coDtents, as tbera are not many sab- 

t color it. 

ar of the water serrrs rhicAy to discover 
e of solpburetted hydrogen in it ; such 
oontaia this 8ubBtaaL'« have a peculiar 
I, aomewbst resembling rotten eggs. 

of ■ spring, provided it be perfectly 
i by repeated trials, may afford some 
Uons with respect to the contents. It 
very sensible by tasting water, tu which 
I salts that are usually found in such 
diMolved in Tarioas proi>ortions. Ttierc 
depeudrnce, however, to be placed on 
of inrestii(tition ; for in many springs, 
aolpbate of soda is disguised by that of 
united with it. The water iao is not 
lMt«d It the spring, but after it has 
time. This precaution must be par- 
with respect to such waters as 
with carbonic acid ; for the other 
eontained in them make no impression 
ipie, till the carbonic acid has made its 
pd it is for the same reason that these 
lit be eraporated in part, and then tasted 

the ipecific gravity of any water contri. 
little towards determining iu contents, 
not be entirely useless to know the spe- 
of the water, the situation of the spring, 
Ind of sediment deposited by it. 

ination of the water by means of re- 
what they contain, bat not how much 
■iociple. In many inatances this is as 
inquiry demands ; and it is always of 
the proceedings in the proper analysis. 
■olutely necessary to make the experiment 
r just token np from the spring, and after- 
i neh as has been exposed for some hours 
air; and sometimes, a third essay is to 
rith a portion of the water that has been 
afterward filtered. If the water cou- 
•aline particles, it must be evaporated ; 
be moat sensible reagents do not In the 
it, if the salts, the {ircsence of which is 
orered by tbera, are diluted with too great 
f of water. Now, it may happen, that a 
iU be impregnated with a considerable 
f nline particles of different kinds, though 
kcm mty be present in too small a ijuan- 
Vrhieh reason the water must be examined 
time, after having been boiled down to 

of which the presence is discover' 

are:— 

add. When this ii not combined 

or not with sufficient to neutralize 

}n of lime-water will throw down a 

aolttbte with efTervesoence in muriatic 

infusion of bimua Is reddened by it ; — 

color gradually disappears, and may be 

> by the addition of more of the mineral 

boiled it loeci the property of red- 

td Utuut. A«cording tg PlaS, 



tlie most sensible test of this acid tt acetate of 
lead. 

3. The mineral acids, when present uncombined 
in water, give the infusion of Htmos a permanent 
red, even though the water has been boiled. Berg- 
maun has shown that paper stained with titmos is 
reddened when dipped into water containing jjf^ of 
sulphuric add. 

3. Water, containing sulphnretted hydrogen gu, 
ia distinguished by the following properties ; it ex- 
hales the pecnliar odour of sulphuretted hydrogen 
gas. It reddens the infusion of litmus fugaciuusly. 
It blsckena paper dipped into a solution of lead, 
and precipitates the nitrate of silver black or brown. 

4. Alkalis, and atkoUne and earthy carbonates, 
are distiogaished by the following tests: — the Infu- 
sion of turmeric, or paper stained with tumieric, n 
rendered brown by alkalis ; or reddiah-brown, if 
the quantity be minute. This change Is produced 
when the soda in water amounts only to y^xr P^rt. 
Pajver stained with Brazil wood, or the Infusion of 
brazil wood, is rendered blue; but this change Is 
produced also by the alkaline and earthy carbonates. 
Bergmauo ascertained, that water conuining p^ ^j^ 
part or carbonate of soda, renders paper stained 
with Brazil wood blue. Litmus paper reddened by 
vinegar, is restored to its original blue color. This 
change is produced by the alkaline and earthy car- 
bonates also. When these changes are fhgucioai, 
we may conclude, that the alkali is smmnnia. 

ii. Fixed alkalis exist in water that occasions a 
precipitate with moriste of magnesia after being 
boiled. Volatile alkali may be distinguished by the 
smell ; or it may be obtdned in the receiver by 
distilling a portion of the water gently, and then it 
may be distinguished by the above testa. 

6. Earthy and metallic carbonates are precipi- 
tated by boiling the water containing them ; except 
carbonate of magnesia, which Is precipitated but 
imperfectly. 

7. Iron is discovered by the following tests : — 
The addition of tincture of galls givc« water, con- 
taining iron, a purple or black color. This test in- 
dicates the presence of a very minute portion of 
Iron. If the tincture have no effect upon the water, 
after boiling, though it colors it before, the iron is 
in the state of carbonate. The following oboerra- 
tions of Weatrumb on the color which iron gives 
to khIIi, OS modified by other boflics, deserve at- 
tention. A violet indicates an alkaline carbonate. 
or earthy salt. Dark purple indicates other alka- 
line sAtts. Purplish. red indicates sulphuretted hy- 
drogen gaa. Whitish, and ihen black, indicates 
sulphate of lime. Mr. Pliitlipe has lately ascer- 
tained, that, while the iron is little oxided, the pre- 
sence of lime rather facilitates the application of this 
teat ; but the lime prevents the teat from acting, 
provided the iron be considerably oxidized. The 
Prussian alkali occasions a blue prectpitate in water 
containing iron. If an alkali be prL-st-nt, the blue 
precipitate does not appear unless the alkali is satu- 
rated with BU acid. 

fl. Magnesia and alamino. The presence of 
these earths is ascertained by the following tests :^ 
Pure ammonia precipitates them both, and no other 
earth, provided the carbonic acid have been pre- 
viously separated by a fixed sikali and boiling.— 
Lime-water precipitates only these two eartba. 
provided the carbonic acid be previously removed, 
and the solpbaric acid alto, by meana of nitrate of 
barytes. (To be amltitmti,} 



136 



MAGAZINE OF SCIENCE. 



MEMORANDA. 

To Hlkitm Ivory that Aaifiecome Red or Vellow. — 
DoU iilam in water ; ;into this immerse your ivory, 
And let it remain in sn bvur ; then rub the ivory 
with a cloth, wipe it clean with wet linen rag, and 
]ay it in a moistened cloth to prevent its drying too 
quickly, which causes it to crack. 

Bwiporation qftht Sea, — In the beginning of the 
]ut ceulury the phlltrtophical world was agitated 
with an inquiry into the origin of rivers, the vast 
waten of which are unceasingly being discharged 
Into the iea. One party contended for the exist- 
eoce of a large mass of water within the bowela of 
te earth, which supplied not only the rirera but 
ettie ocean itself. Another party anerted, that the 
vaten of the ocean were eonreyed back by some 
mbterrancoua passages to the land, and being fil- 
trated in their paasage, returned again to the sea in 
the course of the rivers ; this opinion was however 
too absurd to be long maintained, being contrary to 
all the known principles of bydroftatios. In oppo- 
sition to these hypothrses, our celebrated country- 
aojin, Ilolley, contended that the immense deposi- 
tion of water iu consequence of evaporation was 
folly adequate to the whole supply, which opinion 
ma oOBfirmed by the following experiment. He 
took a retacl of water, made of the average saltoess 
of the ocean, which he ascertained by an hydro- 
meter ; and having placed a thermometer in it, he 
brought it by a chafiug-dish to the heat of the air 
Sn our hottest aammer. This Teasel witli the ther- 
mometer in it, be placed in one icale, which he 
lucely counterbalanced by patting weights in the 
opposite scale. After two hours he found that 
about the sixteenth part of an inch in the depth of 
tbe sorface had escaped in vapor, and cotise- 
qaeatly, that in twelve bourn, the length of a natural 
day, one-tenth of an inch would be evaporated. 
It follows from this experiment that every ten 
square inches of the surface of the water yield a 
cubic inch of water in vapor per day, every square 
mite 6.914 tons, and every square degree 33 millions 
of tons. Now, calculating the Mediterranean at 
4(f long, and 4 broad, we have a surface of 160 
sqTiare degrees, from whence will evaporate 3,280 
millions of tons per day, a quantity, which renders 
it highly prolwble that tlie rivers msy be supplied 
by the deposition of water raised by the proceaa of 
evaporation. 

New Mod* ((f Preparation qf the Daguerreotype 
Plstttf by which portraits can be taken in tbe 
abort space of time from five to fifteen seconds, ac- 
cording to the power of light, discovered by A. 
Ctaudet in the beginning of May, 1841. — ** My im- 
provement,"' aaya the author, "coosiats in using 
for the preparation of the plates, a combination of 
chlorine with iodine, in the ntate of chloride of 
ioftinc. I follow the preparation recommended by 
Daguerre. After having put the plate iu tbe iodine 
box for a short time, and before it has acquired any 
appearanco of yellow color, I take it oat, and pass 
it for about two seconda over tlie opening of a bottle 
containing chloride of iodine ; and immediately I 
patitigiin in the iodine box, where it acquires 
Tcrytoon the yellow color which showi that the 
plate ia ready to be placed into the camera ob^cura. 
I have substituted for the chloride of iodin*-, chloride 
of bromine, and have found nearly the same result ; 



but I prefer chloride of iodine as produdog a 
ter effect ; and besidei. on aeccnnt of the 
sraell of bromine. The result of my pi 
such that 1 liBve operated in ten aeconda, 
same apparatus which, without any ohlonac^ 
quired four or five minutes ; when using oolt-i 
original preparation of Dagverre, I have ol"^ 
an image of clouds in four tecondt." — Aihem 
Snltmff Meat. — ^The method for which a 
has been lately taken out by Mr. Payne, is 
scribed.— The meat to be salted is placed 
atroog iron vessel, which is dosed in an «ir-t 
manner, and the air exhausted from it by men 
an air-pump ; a communication is then opened* 
a brine vessel, whence the brine flows into the 
ceiver, until it Is about half filled ; the afr-pamp 
then again worked to draw off every partick eCl 
from tlie meat, Slc. The brine ia then permitted > 
flU the receiver, and a farther quantity ii inj* 
by means of a common forcing-pump, the pi 
being regulated by a safety-valve loaded witbH 
100 or lOOIb. upon the square inch. After 
ing under this pressure for about fifteen 
meat is cared, and may be taken out of tbe i 

£.Ttraordinary Phenomenon at Derby. — ] 
a heaTy thundcr-Btorra, which happened 
the rain poured down in torrents mixed wil 
melted ice, and, incredible as it may appear, 
dreds of small fisbes and frogs in great abt 
descended with the torrents of rain. The ftA ' 
from half an inch to two inches long, and afeiP4 
Biderably larger, one weighing three ounces; 
of the fish have very hard pointed spikes on 
backs, and are tcommonly called Btickle-ba£fct| 
Many were picked up nlive. The itogi were 
the size of a hor«e-bcan to that of a garden- 
numbers of them came down alive, and 
away as fast as they could, but the bulk vrer^j 
by Che fall on the bard pavement. Wa ha "* 
some alive which appear to enjoy thamaoli 
gloss with water and leaves in it. — Ske0Md, 
Engrarittff in Krtiefhy mean* qf Voltme 
city.— Mr. G. H. Hoffman, of Margate, 
certain modifications of the processes at 
use, the result of which he conceives will btfl 
grently superior. A flat copper-plate, sudk^ 
used by engravers, is to be covered with 
etching-ground ; in this grooves are to be 
or cut, or dots stippled with a Want or sharpj 
down to the copper, as in common etchii 
plate is then to be immersed, and the copper< 
■ited in the usual manner, and the electric 
to be continued until the deposit forms 
sheet. The compound phite is then to ba! 
over a spirit lamp, so that the etching grooi 
be melted and run out. The plates are IheiLJ 
separated ; and, after carefully washing with ' 
of turpentine, the engraving will appear, poU 
sharp and 'perfect. 

Stood.— Vt. Carbonel. of Barcelona, ba 
ployed serum of blood on an extcnsiTe scale in 
ing. Mixed with powdered quicklime or alokc 
to a proper consistence it is easily applied on 
to which it thus gives a coating of stone t '" 
dries quickly without any bad smell, and 
action of sun and rain. The wood abonld 
covered with a coating of plaster, the 
mu?t be rabed as it is used, wjd the 
not be stale. It may be also used as a cement 
water pipes and for stones iu building under 



LoMDoM.— Pnntad by 1>. Fra*cu, «. While lloru Laoe, Mkls End.— PnblUhwl by W. BairfAiif. 1 1 ..,„., 

ComoiUBicaUoaa, (ivblcli are aaJwcrcd MooUUy.) to bf addrcaied to tbe Editor, at ST. Coltaga Grova. JUle c-mJ 



S^GAZINE OF SCIENCE, 

■ ^nH ^cgool of <3Lvt9, 




MAGAZINE OF SCIENCE. 



BTGROMETeKS. 

fttf Ifa* ^ ii Mt oHly suerptibk 

It ^gkmf^Hmdonj to pki. 

■• ^i^Re of noiftare, c*pe- 

• CRM aiiaace •■ the kuuB body. 

cfipcts of BaUiro^ 

«€ tt« Ayyrvaef er, 

tW tomuhty ol 

of portia- 

tkii pcoftrtf to tbe 

F«r thu 

■r bovo w pIsoM aoroov 

Omu. ■• tttf Kkefifano 

isritiimihekanBl 

firaMiotfacv 

hj ■ohfii. Th< 

AoaU Uftimcd of piBceoof 

oaife lifiidr bel««a 

*7. Aa tW botfd goto «c£, 

tkerfcsrao 

tfao Ai^iii of hcod^. Thu n- 

k W«^aH« 7«t of kttl' fcadicol vtiGtT. 

s toDK IBM okr tW 

it !• cb«r|ed; be. 

A«ho«4 ■WJMJTlirilWM kH OMUbfetO 






if • ««l «rik. iw^ o« • omB ealMK. pk»d ■ lb« 
«afr«of ftMM^ bM^tho oCbor otfnaiiyof tbt 
karlMBM ifawHfc Idbi ««Mn of tbooovcrgf tbo 
>■!, ifc /ii Liii I liwaii^»yA »JmAM»te »smI 

K; M(bt bi(|^o«»flJltiAamo^of ipopcr 
Vt«4l»ih»0KtnHX|of«h*boarl. U ordor 
•i ^bt4 oc«M» to «ho tttr, Ik k ■■liii Hbot lb* 
riite of tk* bM ftbovU bo|oribnlv4 irttk bisli^ 
tfWI Ibo ^ «M ^"v* * f< >< * r»MI* tbtoocbft. 
Wb<» ^fc^^tiiiBwl k m— i » Ar or mtimm 

faH^ji wfciibJte u ^Nk t w iii l» >— Ak F f "<y i 
fniiMiotiiW>s •» ift % ««»7 ba^M«l bMlrtMoaL, 

9. «i«y«o4 ftMtoMMK'tlw fbM bfoiftrkcor 
plwo of «m*( »iHioil «o ill ffottbn of gnvity. ■»! 
M Ikt ot^ fo4 f4 «b» otHOf bo oIlMlwrf !• • book. 
JUmHI^ m Iho Mr Ii »art or hm aofat. fov will 
Mi Ikl iMiA H^i« tif» tOM>4 fai OM direecioa or 
to iMitbn TVi taott »oriuo« may b« corered 
witb ibittcW«, h>p«Tt«li«i beUM;dof»ncod by the « 

St»Hoauflb« »u>*ltbebflIwii»tbeeieT«t«l abow 
a baao Ukat iK* M' w*y havrnrcrM to the slrinf. 
4, ir« |'i<^v v^*»t4[Ut iv whipcord bi" ni»He fait 
tt oiw ralf»«vitt. K. ^ t^mtrirJ o^cr dilfprtnt pul- 
liM. ai B,t\ b, K, F» «. (r»«. »>. «<•« to make 
Mvvrat luma bocbwMtb utd forwards ; sind if a 
^,l»Ki \' t^ ■ubiM'ntWil fnMu Uitf other extremity, it 
ip,^ -cOf fiiU iu a more 

^„, .<f tbc nooisture or 

i>i iht« Mir, AiOMuiii^ 4A tbo nnmbef of turns 
•U ami fi>rwftnU la |rrt«tar. But ihia will 
' •« iiulri H K, tuminjt on a 
kucit a mannrr that the |>art 
<ritf«r than I II. br made fast 
' tba oonl U. Tbe aligfateat 
( of th« air will be maoifeftttd 
tndfix. 
. tuay b« ooutructed alio in ifae 




tocr. 

4 



bUowing manner : — Extend k eord, & or 6 feet ia 
kogtb, between the lopportfl A and B, (Fif. S,) an4 
auapcnd &Dni themiddleof it C, a weight P byo thraod 
PC, the weight will as before aaccod or dttctod 
■eoordiBf to the degree of humiditj of the air acta* 
•ting tbc index attached to it, in a similar manner 
to tfae former inttruroent. 

6. Mouc may also be employed to indfcate tfao 
dryneaa or mouture of tbe sir. The aound of a 
ilito ia higher daring; dry (ban darini^ wet weather 
So alao stringed inttrumenta l^t in tune are w 
known to require tuning again each day or 
ihey arc pUyed upon, not merely because of 
itretcb'ing of the utringi, but btcanae of (to 
weather. Let a piece of catgut then, extended bcv 
t»eeo two bridge*, be put in a state of vibratioa 
lo aa to agree with any certain note in music, oe- 
oordiog to a tuning fork, ^^'hen tbe weather be* 
cornea moiater, the string will emit a loirer sound, 
and the contrary will be the case when the sir bo« 
eomes drier. 

7. Tbe balance hygromeitr is well known ; it 
litU of a acaie beam, suspendtrd on a proper 
bearing at oae end a sponge dipped in salt and 
and afterwards dried in the oir, nnd at the other 
ft weight which is exactly equivaJent to it. £ro 
may put into the scale of a balance any aalt 
attract* the moisture of the air, and a correa; 
ing weight into tbe other scale. In the casta 
of the sponge and tbe scale of salt, this part 
sinfc down during damp weather, and thereby 1 
coto tbo atate of the atmosphere. An iodcx, 

out tike different degrees of drought or 
ttay be easily adapted to it. This ioat; 
ia* hoverer. worse than any of the rckt ; for salt, 
iiBMsrifd in moist air, becomes charged with a 
great deal of humidity, but loses it very slowly. 
when the air becomes dry ; iioCash* the chloride of 
Haae, ood BUmeroua other salts, eren imbibe moit- 
laic, omtil they arc reduced to a liquid state. 

ft. Tbo hygrometers commonly aold at tha toy 
ifcopo oro eonatrocted on the principle of that d*. 
oarJbe4 ia poiagraph No. 3. One of them coasisiBof 
a kiad of box, the fore part of which repreaenls • 
•Aid« with two doon ; on one side of the metid 
plalo vbick toras round, or aa ia substituted het% 
■■ilj a doable arm or suspended balance beaas, 
flmdi the iguri <rf a person with an umbrdb aa* 
defeaca froa the rain ; and ou tbe other, a peraoi 
vtlboot a hat, or in gay attire, as if aware of the eon- 
tjaaapco of fine weather. The appearance ul one 
of theae indicates damp, and that of the other, dry 
weather (see Fig. &). Another toy hygromoltf^ 
upon the same principle, is made to repreaeat a 
fiiar, with a large moveabia coal orcr his bead, aid 
beariog in one hand a theriDomeicr, that tbe iaatni> 
meat may scrre the double purpose of an hygfO* 
meter and s thermometer (see Fig. 6). The bygn- 
netrical part is very easily cooatnicted. Behied 
tlie neck of the figare projects a thin tin tube, about 
2 inches long, this tube comes quite through tha 
thin board upon which tbe figure is painted. Oa 
the bock part of the hood is a hole, wbicfa AH 
loosely over tbe tube, so tbst, as ftir aa thia is eoi^ 
cerned, the hood may move round in any direotXda* 
To the front side of the hood, at a part correapood- 
ing with the end of tbe tube, is glued the end of a 
piece of cat^t, the other end ia drawn through tbe 
tube and fastened by paasing through the m-dllr of 
a cork, which fits tbe backward end of tbe luU \— 
thus, the catgut being fixed at one end, aa it twitts 
or oalaiBtl with cbangei of the waatherf the hood 



-J 



MAGAZINE OF SCIENCE. 



139 



if tbe monk'* brad if wtt, or rnts upon 
bni when dry. These pret«ndrd bygro- 
\ttTTe for no other purpose than toomuAe 
the pbiioiopber mu»t observe itnt u the 
|ef btnaiditj ira tranimicted to thia in- 
Wf degrees, it will indicnto mottture or 
jffaeo the state of tbe atiDoa[>here nmy be 
^t. Tbe circumstance, too, of these 
p9 being genemlly |]lnct-din a room where a 
1^ dou not coDtribute to their luefnlnew. . 
bee a perfect hygruraeter, na well as any 
|BophioKi inttrument, we must call in the I 
Ice, and with its unerring prindplea aa ■ 
|nl perfect hygrometcTi bafe been con- 
fevfl shall Bt preaent dejcribe two of tbe 
b — those of Profewor Daoiell, of King's 
Itondon, and of Mr. F^ge. To under- 
pnndptes upoa which these instruments 
Icted, it is to be premised that " the tem- 
fc which dew ittffina to be dejKisttcd, ia a 
r the moisture of tbe air." Referring to 
llrfaich ia a rqiresentaltoo of DanieU's by- 
Hht ball A ia of black glass, about V2b 
taicter, and connected with a transparent 
P of the same size, by a bent tube C C 
I of 10 inch in diameter. A portion of 

rier, sufficient to fill about three-fourths 
A, is introduced ; a amnll mrrouriHl 
ber. with an elongated bulb, is fixed inside 

rB, and the atmospheric air being ez- 
vhole ia hermetically- sealed. The ball 
iRd with muilin, and the whole ii sap- 
I a brass stem P G, on which ii another 
IhErmomeier. The tube can be removed 

ring tube H ; and the whole instrument, 
of ether, neatly packed in a box, which 
iMed ia tbe pocket. 

Ib-poiot, sttd, consequently, tbe humidity of 
i ascertained thuf. The ether being all 
bto the ball A, by Inclining tbe tube, the 
placed tterpendicularly, the temperature 
F It noted by the common thermometer, 
klacfaedto the centre iftand FG, and ether 
ly dropped on the mtiilin cover of I) ;— 
\ produced by the evaporation of the 
0ein«a the elastic ethereal vapor within 
l^d if tbe thermometer inside tbe Umb C 

re that Instant, we obtain the true dew- 
Mi the temperature ibuwn by tbe other 
Icr. To ascertain the degree of humidity, 
i»ve recourse to a set of tables constructed 
lrpo«e, whirb may be found as originally 
P by Dr, DaltOD, for every degree of the 
ier, in the fifth volume of th? ** Man- 
psBsactions," or by the following for- 
ascertains the moisture contained in a 
Its weight in grains will be equal to 

where / is the temperature of the ex- 

'■nd p the elasticity of the ethereal vapor, 
itare shown by tbe interior thcrmo- 

inent invented by Mr. Jones, is de- 
the "Tracts of the Society of Useful 
" U being on exactly tlie same prinrJple 
invention of Dsniell, bQt simpler in 
more compact, and less expensive. — 
ice would certainly scirccly imply as 
seen ia Figure 4, and consiftn of s de- 
ial Cliermometer, with its tube at A U, 
bring its cylindrical ball C parallel 
JUtle distance from its item. The 




bulb is one inch Ions, and is terminated by a sur- 
face of black glass which projecln somenhit beyond 
the sides of the bulb. The bulb below l}ie ilattened 
surface is covered with black silk, llie instrument 
is supported on the wire £ F. which is attached to 
the scale by a pivot at top, that allows the bUck 
surface to be inclined to the light, and the whole aa 
in the case of the former instrument, is, with a phiil 
of ether, contained tn a smnll CAse. When used, 
the temperature of the air is first noted ; tbe ether 
is poured on the lilk cover of the bulb, and the 
condensntion of the dow is seen on the bUrk ex- 
tremity of tbe bulb. The calcolstion to find tbe 
degree of humidity is the same as before; an ordi* 
nnry thermometer must be used along with this In- 
itrument, — Danietl's hu one attached to it, 

CALOTYPE PICTURES. 
Mm, H. F. Taldot, so well known for his re- 
searches and dificovrries, relative to photographic 
drawing, and of which art wc have, from time to 
time, recorded the progress, has been and u itUI 
occupied with the iuterestiog subject, snd seems to 
have brought it to o degree of perfection hitherto 
unknown, which Uie following paper, read st the 
last meeting of the Royal Society, will show. Our 
resdcrs wilt, by comparison, remark that there are 
so many points about it so entirely different from 
the old process, that it may justly be ci^risidered a 
new art altogether ; and as such, Mr. Talbot has 
given it the new name of Calotype, Wc give Mr. 
Talbot's paper entire, and nearly vrrbotiin. 

Preparation qf the Paper. — Take a sheet of the 
best writing paper, having a smooth surface, and « 
close and even texture. The watermark, if any, 
should be cut off, lest it should injure the appearance 
of the picture. Dissolve 100 grains of crystallised 
nitrate of silver in six ounces of distilled water.— 
Wush the paper with this solution, with u soft brush, 
on one side, and put a mark on that side whereby 
to know it again. Dry the paper cautiously at a 
distant fire, or else let it dry spontaneously in a dark 
room. Wlteu dry, or nearly so, dip it into a solution 
of iodide of polaet>ium, containing 500 grains of that 
salt dl^^solvcd ill one pint of water, and let it stay 
two or three minutes in this solution. Then dip it 
into a vessel of water, dry it lightly with blotting- 
paper, and finish drying it at a fire, which will not 
injure it even if held pretty near ; or else it may be 
left to dry spontaneously. AH this is best done in 
the evening by candlelight. The paper, so fur pre- 
pared, the author calls iodized paper, because it has 
a uniform pale yellow coating of iodide of silver. It 
is scarcely sensitive to light, but, nevcriherless, it 
ought to be kept in a portfolio, or a drawer, until 
w&tited fur use. It may be kept for any length of 
time without spoiling or undergoing any change, if 
protected from the light. This is the first part of 
the prepurstion of CtUotype pa[>er, and maybe per- 
formed at any time. The remaining part is best 
deferred until shortly before the paper is wanted for 
use. When that time is arrived, lake a sheet of the 
iodiied paper and wash it with a liquid prepared in 
the following manner :— Dissolve 100 grains of crys- 
tallized nitrate of silver in two ounces of distilled 
water; add to Ibis solution oae-sixth of its volume 
of strong acetic acid. Let this mixture be called A. 
Make a saturated solution of crysUlltxed gallic add 
in cold distilled water. Tbe quantity dissolved U 
very small. Call this solution B. When a sheet of 
paper is wanted for use, mix together the liquids A 
and B in tqutl volamcs, but only mix ■ small quso- 



5 



140 



MAGAZINE or SCIENCE. 



tity of them it » time, bectute the mixture does not 
keep loa^ without Bpoilin;. I ihall call this mijclure 
the f7ollo-nitrate of W/rrr. Then take a sheet of 
iodurti paprr aod wAsh it over with thii gaih-Httrate 
qfnirrr, with & toft brash, takiog can to waah icoa 
the side which has been preTioutit}' marked. Tliia 
oprnitian ahoiUd be performed by candlelight. Let 
the paper rest half a minute, and then dip it into 
water. Then drr it lightly with blotting paper, and 
finally dry it eauiionaly at a fire, holding it at a con- 
aiderable distance therefrom. When dry, the paper 
is 6t for use. The antbor has named the paper thus 
prepared Cahtype paper, on account of iu great 
utility in obtaining tbr pictorea of objecta with the 
camera obscura. If this paper be kept in a press it 
wUl oft<-n retain its qualities in perfection for three 
months or more, being ready for use at any moment ; 
but this ia not uniformly the case, and the author 
tticTtffure recommends that it should be used in a few 
hours after it bss been prepared. If it is used imme- 
diately, the last drying may be dtspemed with, and 
the paper may be used moist. Instead of employing 
a solution of crystallized gallic acid for the liquid B, 
the iinchtre of galU dilated with water may be used, 
but he does not Uuuk the resulti are altogether bo 
satiafactory. 

Pie <iftht Paper. — The Calotyp§ paper ii sensi- 
tire to light in an extraordinary degree, which 
transcends a hdndred times or more that of any kind 
of photographic paper hitherto described. This may 
be made maDifest by the following experiment : — 
Take a piece of this paper, and hmving covered half 
of it, expose the other half to daylight for the space 
of one $econd in dark cloudy weather In winter. — 
This brief moment safiices to produce s strong im- 

Ereuion upon the paper. But the impression is 
iient and invisible, and its existence would not be 
suspected by any one who was not forwamed of gt 
by previous experiments. The method of causing 
the impression to become visible is extremely aiiuplc. 
In rnosiits in washing the paper once more with the 
fjaUo-uitrate of niters prepared in the way before 
described, and then warming it gently before the fire. 
I n a few seconds the |iart of the paper upon which 
the light has acted begins to darken, and finally 
grows entirely black, while the other port of the 
|>aper retains its whiteness. Even a weaker im- 
preseion than this may be brought out by repeating 
the wash of gallo-nitrate of silver, and agiun warm- 
ing the paper. On the other band, a stronger im- 
prcssion does not require the warming of the paper, 
for a wash of the gallo-nitrate suffices to make it 
visible, without heat, in the course of a minute or 
two. K very remarkable proof of the sensitiveness 
of the CaloC)-pe paper is aiforded by the fact stated 
by the author, that it will take an impression from 
limple moonlight, not concentrated by lens. If a 
le&f is laid upon a sheet of the paper, an image of it 
may be ohbuned in this way in from a quarter to 
half an hour. This piper being posaesaed of so high 
a degree of sensitiveness, is therefore well suited to 
receive imagea in the camera obacura. If the aper- 
ture of the object-lens is one inch, and the focal 
length fifteen inches, the author fi nd]> that one minute 
is amply sufficient in summer to impress n strong 
image upon the paper of any building upon which 
the sun is shining. When the aperture amounts to 
one-tliird of the focal length, and the object is very 
white, as a plaster bust, &c., it appears to him that 
one eeeofid is sufficient to obtain a pretty good 
image o( it. The images thus received upon the 
Caiotyjw ps^ier are fur the must part iuviaiblo im- 



led with 



preasiona. They may be aaade ▼iaibte by the pR»- 
cesa already related, namely, by washing theoi willi 
gallo-nitrate of silver, and then warming the paper. 
When the paper is quite blank, as is genetmlly tba 
case, it is a highly curious and beaotiful phaaoae- 
OOQ to see the spontaoeous commencement td tf» 
picture, first tracing out the stronger outlinca, aad 
then gradually rilling up all the numerous and com- 
plicated details. The artist should watch the pio- 
ture as it dcvdopca itftclf, and when, la hla jodf-* 
ment, it has attained the greatest degree of streogOl 
and clearness, he should stop further progreaa by 
washing it with the fixing liquid. 

Thefjcing procett. — To fix the picture, it ahoold 
be first washed with water, then lightly dried with 
blotting paper, and then washed with a solnl 
brotnide of potatfium, containing 100 graioa 
salt diuolred in eight or ten ounces of water. 
a minute or two it should be again dipped in 
and then finally dried. The picture is in this 
ner very strongly fixed, and with this great adrtzt* 
tage, that it remains transparent, and that, there- 
fore, there is no difficulty in obtaining a copy froa 
it. The Calotype picture is a vegafive one, in which 
the lights of nature are represented by shades ; bnt 
the copies are poniive, having the lights conforma- 
ble to nature. They also represent the object im 
their natural position with respect to right and left. 
The copies may be made upon Calotype paper in ■ 
very short time, the invisible impresaions beitf 
brought out in the way already described. BoC the 
author prefers to make the copies upon photogra- 
phic paper, preiuu-e^ in the way which he orifinaUf 
deacribed in a memoir read to the Royal Society tn 
February, 1339, and which is made by washing the 
beat writing paper, Jirvt with a weak soluboa td 
common salt, and next with a solution of nitrais of 
silver. Although it takes a much lunger time IQ 
obtain a copy upon this paper, yet, when obtainedr 
the tints appear more harmoaioua and pleaaii^ to 
the eye ; it requires, in general, from three minatoa 
to thirty minutes of sunshine, according to cdicsm* 
stances, to obtain a good copy on this sort of phe* 
togruphic paper. The copy should be washed and 
dried, and the fixing process (which maybe deferred 
to a aubsequent day) is the same as th«t already 
mentioned. The copies arc made by placing tM 
picture upon the photographic paper, with a board 
below and a sheet of glass above, and pressing the 
papers into close contact by means of screws or 
otherwise. After a Calotype picture has for* 
niabcd several copies, it sometimes grows faial* 
and no more good copies can then be made from it. 
But these pictures possess the beautiful amlexiraor- 
dinary property of being susceptible of rerival. U 
order to revive them and restore their original tip- 
jMrarance, it is only necessary to wash them again bjf 
candlelight with gallo-nitrate of silver, and ww 
them ; this causes all the shades of the pictum Itt 
darken greatly, while the white parts remain ■»- 
affected. The shaded parts of the paper tfatu ac- 
quire an opacity which gives a renewed apirit and 
life to the copies, of which a aecond seriea may now 
be taken, extending often to a very considerabla 
number. In reviving the [licture it sometimea h^u 
pens that various detaila make their app 
which bad not before been seen, ha1lt1^ been 
all the time, yet, nevertheless, not destroyed by 
long exposure to sunshine. The author termii 

these observations by stating a few expenmenta 

culated to render the mode of action of the sen>Ilt«» 
paper more bmiliar. — 1 . Wash a piece ut Uie iadtsed 



MAGAZINE OF SCIENCE. 



141 



i the gmUo-oitrate ; expote it to lUylighl 
»nd or tivo. and then withdraw it. The 
L toon brKiD to darken spontaneously, and 
quite bldi:k. — 2. Tht name as before, bat 
per be warmed. The bUckeniof will be 
' in coasctjueiue u( the warmth. — 3. Put 
ftp of the gaJlo-nitrate on one port of the 
BWifCcn mother part of it more sparingly, 
it exposed to a Terf faint dnylight ; it 
that the leaser quantity produces the 
bet ID darkening the pajwr ; and, in ge- 
n}l be seen that the most rapid darkening 
at the moment when the paper becomes 
also, if only a portion uf the paper is 
it will be obserred that the edges or 
of the moistened part are more aoted on 
an any other part of the torCace. — 1. if 
lifter being moistened with the gallo- 
washed with water and dried, a alight 
daylight no longer inlficei to produce 
discoloration ; Indeed it often produces 
Uut by subsequently waabing it again 
•nitrate and warming it, the lune de- 
lormCion is developed as in the other 
ents 1 and 2). The dry paper appears, 
be equal, or superior in sensitircoeaa 
only with this differeuce, that it re- 
tttal instead of an actual impresaioa 
Kgbt, which it lequires a subsequent pro- 
pdope. 



»VE)i£NT IN THE DAGUERRO- 

TVPE. 

bey with which the artists of Paris have 
ttrom yi. Daguerrc information respecting 
iDTery of his relative to the Daguerrotype. 
I hare forced a communication from him 
tt he would, himself, have chosen to make 
»esiiDenta not being complete — not having 
I yet, perfect eridences of the extraordi- 
lie results which he expects from tbcm. 
(St the sitting of the 2Ktb June, explained 
Idemy the new principle of which the dis- 
■iats, but on the ttutb<jrity of M. Daguerre 
I witboot the production of any specimens 
■i his BSMrtiooa. Contrary to what we 
^unagined, M. Arago withholds the sanc- 
b anthority, declaring that he has not. 
Bra any of the experiments or results ; — 
inciple itself ts one of greater importance 
•ific bearing, than for any orlistic appti- 
Irbich it ia Bosceptible. The history and 
I of the discovery is as follows ; — Aban* 
B search, in which so many have been 
ber some fresh substance more senaitive to 
of light than those hitherto employed, 
rre submitted bis plate, merely washed 
t, in the ordinary manner, to the inftaence 
tty ; and found that it had attained such 
Ne d^rec of aensibility, that no mechttoiam 
Ideatly nipid in its action to exj>o«e it 
to the impression of light — that is, a plats 
td and placed \a the camera obteura an- 
turing the one unapprecinblc moment 
b opening and shutting the diaphragm 
m the objective glass> such varied degrees 
ion, that the portion first brought into 
lUi the light i« already too prutbuudly 
I it c&D touch the )atf r portions. The re- 
V&fuaed and clouded image. To meet the 
H. Uaguerre states, that he has employed 
(which, however, he does not name,) 



leu seositire than the ordioary combination of io- 
dine with Kilver ; and, in the next, instead of sob- 
jecting his plate to the continued action of the 
electric fluid, be admits the intervention of this 
mysCcriotts agent for a single instant only. In more 
precise terms, the plate so prepared and disposed in 
the camera, may be exposed, without injury, to the 
notion of the light for a certain time ; and to cotn- 
monicate to it the exquisite sensibility in questioo, a 
single electric spark suffices ; after which, the plata 
resuming its inertness, time Is afforded to withdraw 
it from the influence of the light — and the operation 
it complete. It U not easy to imagine the artistic 
effects which will result from this remarkable dis- 
covery ; — from the rapid action of the electric spark, 
vast assemblages of men, in the moment of ani- 
mation and impulse, may be caught for eternity, with 
the gesture of the moment in the limbs, and its ex- 
pression on the lips of each. History may be writ- 
ten, by picture, even while its deeds are acting ; and 
nature, in her subtlest movements, be painted by 
herself. M. Daguerre, however, is not satisfied 
with such results as he has yet obtained ; and, in 
yielding to the demand for his secret, bos declined 
confirming it by his specimens, till he has succeeded 
in making them perfect, l^leantime, the important 
part of his communication is the scientlBc pheno- 
menon, itaelf — this wonderful effect of electricity 
on the chemical combtoation, exposed to the action 
of the rays of light. 



LIGHT. 
Tub cause of those senaalions which we refer to the 
eyes, or that which produces the sense of seeing. 
The phenomena of light and vision have always been 
regarded as one of the most interesting branches of 
natural science ; though it is only since the days of 
Newton that they have been examined with such earo 
as to afford grounds for any safe speculation re- 
specting the nstnrc uf light, and the mode of its 
propagation through space. But the solution of 
tbest; two qupations Is involved in very great ditficolty, 
for notwithalonding the splendid discoveries of that 
immortal philosopher, and the long train of inte- 
resting and important facts which have been invea- 
tjgited since bis time, and more particularly since 
the banning of tlie present century, the true theory 
of light still remains an enigma. This docs not arise 
from any difficulty there is in framing an hypothesis 
which ahall afford a mechanical explanation of the 
various phenomena, but from the circumstance that 
more hypotheses than ona have been imagined by 
which all the phenomena can be explained, not 
merely in a general way, but with the precision of 
numerical calculation. 

Properties tif Liffht, — Experiments of the simp- 
lest and most familiar kind suffice to show that light 
is propogated from luminous bodies in nil directions. 
Provided nothing intervenes to intercept the light, 
tbey are seen in ail situations of the eye. Thus, 
the flame of a lamp is visible from every part of the 
sphere of which it occopiea the centre ; and the 
same is the case with respect to a phosphorescent 
body, an electric spark, a ball heated red-hot, or 
light having any other source. The nun throws its 
light, not only on the cartli, but on the ptanela and 
comets, and every other body in the firmametLt* 

Auuiher property of light is, tliut iu a homoge- 
neous medium it is alwtiya propagated in straight 
lines. This 15 evident from various considerations. 
The forms of shadows correctly represent the ont- 
Imes of tbe objects which produce them, as seen 



1 



U3 



MAGAZINE OF SCIENCE. 



from the lamiaou body, which could not bo anle«< 
the light proceeded In ■tratght Udci from the ex- 
tremities of the objects to the borden of the Rbwlow. 
If three plates of metal, each pierced with a smalt 
hole, are placed at Mue distance beluod each other, 
aad iu such positions that the three holes are eiaotly 
in one straight line, the light will pass freely through 
them i but if the holes are not exactly in a itmigbt 
line, no Ugbt will pass, in like manner, if a nnm- 
bcr of simiUr objects are placed bebiad each other 
in a atraight line, the first renderi all the others in- 
Titible to «n eye plsced in the ume line. We 
cannot see through a bent tnbe. 

A third property of light is, that it requires time 
for its propagadoB. The velocity with which it 
passes from one point to another is, however, bo 
greftt, tfaftt. with respect totnytamttri&ldistttnces, 
the passage may be romiderod as instanlaneous. 
Bat astronomy fumishea the means, not only of 
detectiof its propagation, but of measaring its Te- 
locity with grest precisioa. The eclipses and emer* 
lioDB of Jupiter's aatelUtes become Tislble about 
IG min., 26 see. earlier when the earth is at its 
least distance from Jtipitrr, than when it is at its 
groatest. Light, therefore, occupies above s qnar- 
ter of an hour in passing through the diameter of 
the earth's orbit. Now. the sun's diittjincc from the 
earth being nearly 95,0(H>,000 of miles, it foUowi 
that bght mutit travel through space with the pro- 
digious, though finite, velocity of 192,500, or nearly 
200,000 miles, in a second of time, and cooie- 
qucntly would pass roand the earth in the eighth 
plot of a seooud. Astounding as this conclusion Lsj 
no result of science rest* on more certain eridence. 
It is also proved, by the phenomena of nberration, 
that the light of the sun. planets, and all Che fixed 
stars, travels with one and the same velocity. 

When light in ita progress encounters an obstacle, 
or eut«rs a different medium, it undergoes certain 
modi fi ca t ions, depending on the nature of the body 
on which it falls, or the medium into which it enters. 
When it fsUs on a smooth polished surface, a |)or- 
tion of it is regularly reflected ; that is to say, it is 
returned from the surface at an angle equal to the 
angle of incidence, and pursues its course in a 
straight line as before the reflection. The quantity 
of bght thus reflected depeoda on the nature and 
polish of the surface, and on the angle of incidence, 
being greatest when that angle is small : but it is 
calculated that even tlie brightest, and most opaque 
Burfaces, mercury for example, do not reflect more 
than three-fourths of the incident light. Another 
portion of it enters the medium, and <hcre (if the 
medium is homogenous,) pursues a rectiUnear 
coarse, bat diflfering from its former direction. In 
tUb oaae it ii atid to be refracted. The angie of 
refraction depends on the nature of the mcdiucn, 
each diiTerrnt medium having its own peculiar law of 
action on light. In many media, comprehending 
the liquids and most of the uncryitalUzed substances, 
the whole of the refracted light is bent frum its ori- 
ginal direction at the same angle. In many othera, 
as in roost crystallised media, pert of the refracted 
light folluwa one coarse, and another part it a dif- 
ferent one ; the two portions acquiring, at the some 
time, dilfereut physical properties, hi this case 
the refraction is said to be double. A third portion 
of the light fklling on a body is neither reflected 
Bor refracted regularly, but is scattered in all direc- 
tions ; and it is this portion which renders bodies 
vlsUtle. All bodies on which light fulls obsorb a 
certiaa jurt of it; more or less in proportion to 



the opacity. In perfectly opake bodies the absorp- 
tion is total, and the light does not penetrate to 
a sensible depth under the surface. In others it 
penetrates fertber ; but even in the most trans- 
parent it ia gradually stified and lost. A depth of 
only seven feet of pure water ia required to cxtia- 
gnish one half of the incident light. 

Solar light, rrfracled by a prism or other body, k 
separated into a multitude of rays of diflerent colort* 
each of which afterwards proceeds in ita ootsrae to* 
dependently of all the others. The«e difieready 
colored rays possess different physical propertiea* 
and different degrees of refrangibility. It ia to this 
dispersion or separation of light by refraction ihH 
we owe all the pleaaore derived from the vari^atei 
baea of natural bodies. The inveatigalion of ikM 
laws of the dispersion of the oobred raya fformi tfc* 
subject of chromaticw. One of the principal fiuti 
connected with it is, that the dispersion of the raya 
by diflferent refracting aubstances is not proportioued 
to the refraction ; the dispersive power of aoa* 
subsUncea being greater than that of otfaen, vbUi 
their refracting power is less. This fact led tchtfc* 
important discovery of the acAromieiie Ulmeoptm 

Light, on being regularly reflected or refraete^ 
undergoes a modification termed pvtari^atum^ hi 
virtue of which it presents, on encountering aoMhcr 
medium, difTereot plmoaieuof reflection and t^ 
fraction from those preaented hf light which ha« 
not undergone such modification. When a rsy of 
light, having acquired tills modification, ia made t9 
to fall on a plane rejecting surface under a oertai^ 
angle of incidence, no portion of it will be refledad} 
the whole ia transmitted or absorbed. But, in th* 
ease of ordinary light, some portion is always re- 
flected from a polished surface, whatever be tha 
angle of incidence ; the light has therefore acqutfW 
the property of being acted upon in a partiookr 
way; whence Malus. who first investigated tUl 
subject in a philosophical manucr, gave tl*e phinc^ 
mena the name of polariiaiion, from ita analoif |» 
the effect produced by a magnet on a senea ti 
needles. 

The lut property of light which we shall ootSoi, 
as important towards formwg a theory of lis proplk 
gation, is that to which Dt. Young gave the naoi 
of interfertnce. Under certain circumstasaeB* Chi 
rays of light exercise a mutual iofiaenoe on eacdk 
other ; increasing, dimiuishlng, or modifying oaob 
other's clTects according to certain laws. This 
mutual action of the rays on each other, givea titf 
to a great number of the most intricate phenocofM 
of optics, and aifortls a sufficiently simple exploi* 
lion of them, in numerous oases where no other ci« 
planation has yet been found on other hypo 

ThrorifM of Ltff/tt. — Two different theonea 
long divided the opinion of phiiosophera, rea 
the nature and propagatiou of bght. One of 
cnnsiats in supposing it to be compoaed of particki 
of excessive minuteness, projected from the ianl- 
nous body with a velocity eqaal to nearly . 20(MMtt 
miles in a second. This hypotheaia 
by Newton, and, till recently, has been acq 
in by the greater number of writers on optica. 
otlier hypotheaia supposes light to be pn 
the vibrations or undulations of an ethereal 
great elasticity, which pervades all space and 
tratea all aubsiaoces, and to which the lam. 
body givea an impulse which is propagatnl with In- 
conceivable rapidity, in sphehoal superficiea, by a 
sort of tremor or undulation, oa aound is conveyed 
through the atmosphere, or a wave along the sur* 




MAGAZINE OF SCIENCE. 



143 



Both of these hjpotheacs »re ren- 

tla by the great aamber of phenomena 

\cy atford a mechanical explanation ; bat 

also, attended with very great iliffi- 

Ither theories hare alio beeo proposed ; 

ire not met with such general attention 

»phen u to make it necessary to explain 

fTia hr itmtiniwtt. J 



MOSAIC PICTURES. 

Iknovn tliat Mosaic-work constfts of rari- 

piecej oF colored gtoM eitamel ; anj 

these pieces are cemented to|fcther, they 

tegnUr and other beautiful Agures which 

teaaetlated pavements. These pavements, 

of the ancient Romans, have freqnently 

England and other cotuitnes. The 

ictory of Mosaic pictures, in the 

at Rome, and belongs to his Holi- 

in which the establishment is sitn- 
and contains a collection of enamels 
Che form of sticks. These ore arranged, 
to their colors, in on ejctensive suit of 
number of shades of color is 17,000. 
consisting of glass mixed with me> 
ing matter, is heated for eight days in a 
eadi cohr in a separate pot. The 
id is taken out with an iron spoon, and 
tished marble placed horizontally ; and 
rble slab is laid upon the sur^ce, so 
cools into the form of a round cake, 
of -^^ths of an inch. 

the cake into smaller pieces, it 
sharp steel anvil, called tagUolo, 
[idge appennost ; and a stroke of on 
Is given on the upper surface of the 
is tbos divided into long parollclopipcds, 
whose bases ore iS^ths of on inch square. 
ipeds are again divided across their 
tigUtlo and hammer, into pieces of 
of an inch, lu b« used in the 
Sometimea the cakes are made 
places larger. 

\, the enamel, whilst fused, la 
psraUelopiped, or quadrangular 
■re divided across by the tagliolo 
or by a file ; s(»raetimes, also, these 
divided by a saw withost teeth, oonsist- 
blade and emery ; and the pieces 
polished on a horixontal wheel of lead 

Mosaic is formed by applying the gold- 
hot surface of a brown enamel, imrae- 
tbe enamel ts taken from the furnace ; 
is put into the furnace again for a short 
wbisa it is taken out. the gold is firmly 
tihe surface, lu Che gilded enamel, used in 
Rome, there is a thin coat of trojutparent 
the gold, 
it Romans, besides tlie enamel for Mosaic, 
works in enamel. WinVlemonn men- 
titles of a kind of gloss or enamel, for 
t/ifion of rooms ; and be dmcribes a small 
of filaments of cnemdof difTerent 
together by Tuition, emrh tnins« 
of this gave a picture like that at the 
The antique pa^, or artificial gems^ 
lucts of art allied to enamel, 
ly, the paste in which the pieces of Mosaic 
li GoUcd, in lt«iyr ituccoi was oom- 



]>osed of a neasnn of quick-lime quenched in wateTf 
and three measures of pounded marble ; these were 
made into a mass with water and white of eggs ;— 
and this was called Mannoratum : but this paste 
hardens too rapidly, bo that it is bard before the 
workman has time to insert the pieces, and it is in* 
jurcd by damp more readily than the cement made 
with oil. 

The paste now used, is composed of a measure of 
ooenehed quink-Ume, and three measures ot pow- 
dered travertine stone ; tlicse are mijied with linseed 
oil, and ore stirred and worked up every day with a 
trowel. The mass is at first levd on the surface, 
but afterwords swells up. Each day some oil is 
added, to prevent the moKS from becoming dry and 
Intractable. The mass is ready in a shorter time in 
warm weather thsu in cold ; iu summer the mass is 
at its perfection in twenty days ; this is known from 
its ceasing to swell, the water that was in the lime 
having evaporated ; the mass is then uniform 
throughout, like on ointment. In winter, and when 
the air i£ moist, it requires a month to bring the 
paste to perfection. 

The wall to which the Mosaic is to be applied, 
must have the lime taken off its surface ; then fur* 
rows, an inch deep, are formed on the wallf to fix 
the cement. For the same purpoae large-headed 
nails are driven in. and wire is stretched from one 
nail to another. After this, the wall thus prepared, 
is painted over with linseed oil. Then the cement 
is hud on, to the extent of a surface of as many 
inches as can be executed before the cement dries. 
The plasticity and softness of the cement lasts about 
twenty days ; ofler that the oil exudes, and the Ume 
and travertine become a hard maas. The cement 
mode with linseed oil is ycUow \ that made with 
white of eggs is white, and the white cement is con- 
sidered to be a character for distinguishing the old 
Mosaic from the modem ; hut some of the modern 
ia also made with white cement. 



MEDICAL QUALITIES OF SEA-WATER. 
Two very important agents, endowed with peculiar 
virtues in refercooe to the human consHtn H nn , barc 
of late years been mneh comznendad aad employed 
in the practice of median*. I allodb to iodine and 
bromine — both of which have boen detected by recent 
analyaea in sea-water. Independent of these, there 
are otlier very active IngredieiUs in sea-water. The 
first is chloride of sodium, which exists in the pro- 
portion of 1 to 35. or, in otlier words, a pint of sea- 
water contAins 21 6^ grains — that is to oay, some- 
thing less than i os. of common salt. The seoood 
is what medical men call muriate of magnesia, which 
is a combination of chlorine with magnesiuu— 
a salt endowed with well-marked proportiea oo tho 
human frame, and which constitutes one of the active 
ingrcdienU of Fnllna water. To complete this 
analyots, it should be stated that the same pint of 
sea-water contains also 18 grains and i of Epsom 
salts, 1 1 } grains of sulphate of lime, with a very tri- 
fling quantity of carbonate of lime. Aft«r this ao- 
coont it will be readily admitted that sea^water ia, 
in fact, a mineral water to all intents and purpowa, 
and that we may. therefore, look with as mudi con* 
fidenoe for beneficial effects from its employmenU 
whether externally or internally, provided it be judi- 
ciously recoouneuded , as from the employment of 
other mineral waters— proportionate to* and la ao- 
cordaoce with, their respective chrmic al oompOfi- 
tion. — QroHviUe't ^m» if Bnffimtd* 



144 



MAGAZIKE OF SCIENCE. 



NOTES ON THE UONTB OP JOX*Y. 






w»^k^ai ^ftroito/tht Jrtnge^lMe Qitaniiljfqf 



LaxDON ... 
DnLm . . . . 



7 Atft^MOllMlAr' 



MS 

CMS 



Banrntngr. 



1944 



Mmi 



i\'M tncb. 
S>M 



TBB AKIHAL KINOOOM. 

Birdi. — About or before this Mason most long 
birds become aileiit. The Blsckbird, the Pippet 
Lark, the Willow Wren, and aereral otber birds 
tbongh they become silent now, resume their notes 
in September. The Cuckoo leiivcs off its curious 
note. The Qusil, however, begins to make itself 
heard. Mole hlUa msf be observed, some very 
much larger than others : when a hill of enlarged 
dimennions is discovered we may bfl almost certain 
of finding the ue«t beneath. Suppofting the weather 
CiTorable we And the Snake basking on ^the bank, 
the Hedgehog sleeping on the common, and the 
pretty tittle lizards nimbly mnning through the 
brake. The insect race is in ita full vigour, and 
ftboundi iu all situations. The Dragon Flies skim 
■long the margin of the streams and ponds, settling 
from time to time on the water planta around. 
The Cuckoo Spit, the Plant Louse, and the Frog- 
bopper are everywhere in abundanre. It is in this 
month that the Caterpillars of most of the Hawk- 
Moths are to be sought for. That of the Poai- 
Moth may be found on the lower branches of Wil- 
low trees, and must bo sought by the eye, for beat- 
ing the branches will not moke them qidt their hold 
as it does the Noetua. 

THK VKGETABLB KINGDOM. 

PUats indigenous to our climate are now in their 
gnatest number and beauty. The whole of nature 
■eemt but a witdemeaa of flowers. In June they 
were but struggling into existence, now they arc 
Imuriant. To enumerate even a hundredth part of 
the long list of plants in flower would be extremely 
tedious ; yet there arc some whole tribes which 
seem to choose July as their season of blossoming ; 
thus in the early part of the month, the Grass&t and 
the Uosea are almost all in blo&som. The umbel- 
liferous planta and the Brambles moat now be sought 
for. The extensiTe family of the Cnwiiene or Cab- 
bage tribe arc, during this months more particularly 
In perfection, tliough a few of them are in blossom 
at a much earlier season. The Sedums or Stone 
Crops, the House-Leeks, the Rock Rose tribe and 
the Saxifrages, and numerous others, deserve par- 
ticular altentioa at this season. These remarka 
relate but to our wild plants. The garden flowers 
an BO leas abundant and rich, showing the luxuri- 
ance of summer without the incipient decay of the 
aucoecding month. If wc have lost the Peony, and 
the Like, and the Tulip, we can, instead of them, 
admire the Rose, the Pink, and the Honeysuckle, 
and a thousand others equally tweet and beautiful. 

OAaDBMSO OritRATlONS. 

The gardener begins to witueu the success and 
reap the benefit of hU toil in the precedmg winter 
and spring. His cliief employment wiU be in 
gathering his Peas, and his eariy ripe KruiU, his 
Goosoberriea, CorranU, Cherries, Strawberries, and 
Baapberries. He will not, howerer. neglect to pro- 
pagate from cuttings of such planU as arc going 
oat of flower j nor forget to pipe and lay the Pink 
tribe, and gather the seeds as they ripen of such 
planta as may have flowered early. 



NOTES ON THE MONTH OP AUGUST. 



LOHDOII ... 

EomiraoB. 
DoMLia . . . . 



rkermometer. 






UarxHiteier- 



90-OC 

l»8S 

aoiT 



Jtaim. 



S-tt* 



AKUIATXD NATUUE, 

Inhbctis no less abound now than they did In Jtilp 
Piies are well known to swarm in the hooses. 
Wasps, Hornets, Gnats, and God-Fliea in the Gdda. 
Flying Ants appear — Bees kill their Drones — Cha 
Swallow-tailed, and the Ulack-Eyed Macbia 
Butterfly appear. Swallows, Martins, and 
other birds of passage, begin in Uio Utter 
the month to congregate, prcrions to 
their distant migrating expeditions, and 
already are departing. Various birds reaume tbdr 
spring notes. The Nuthatch clutters — the Stone 
Curlew whistles at night — the Goat-Sucker and 
young Owls make a noise in the evening, and the 
Robin Red-Breast sings. The young of animala, 
born in .\pril and May, are in Tigour, and tapiilly 
attaining tlie tut. of their parenta. Rabbita and 
Hares so prolific in the spring begin to cesise thtii 
parental duties, their three or four brtXMls hajing 
grown from under their care, and there being none 
others to succeed them. Young Partridgea ud 
Pheaaanta have attained to nearly their fuU tin and 
strength. 

THK VCnaTAHLS KINGDOM. 

The observations applicable to July, are no \em 
appropriate here on the abundance of floweri ; still 
aa the season adTaoces, we find some fading fj^m 
our sight, and othera of a more autumnal chlrafter 
making their appearance. Wc lose the besutiAU 
Roses, and find but Hipa in their place ; we iHidl 
see the scarcely less beautiful Bramble Flower, hul 
it is joined with the young Blackberry. Trees hava 
lost their flowcra and show more or leaa ripe fruit 
These are the general effects of the chaoge of ata- 
son, yet it is said, and with perfect truth, that the 
first week in August is, if fine, the best in all the 
year for the botanist, aa he will then find the greatac 
number of rare plants, in almost any situaboo h« 
may search for them. Mountainous districts are, 
previous to this, loo cold to yield many flowcn, 
the marshes have till now been too much overtlowed : 
the waters too cold, until the beats of July rs- 
awakens the r^etable cneigy, dries up the auper- 
abnndaoeeof moisture, and Uivigorates the plant so 
aa to produce ita flowers now. Another odvuitscs 
the botanist now enjoys whiiii he did not previoaaly. 
he can in moat cases procure the seed and seed-nsMl 
of his spedmens, and such is in very mimBWW 
tribea absolutely neceasary. 

GARDKymC OPKRATIOXS. 

The gardener will have to attend to lus crops af 
vegetables and fruit, for roost kinds grown in gar- 
dens are now in perfection, as well as his hot-house 
productions. His forced Fruits should all be 
ready early in the month. Peaches, Ncctarioea, 
and Grapes, Plne-AppIes, and Meloni. In the 
open ground, besides culinary vegetables, be will 
gather Plums, Apricots, and the earlier Pean and 
Applea for the use of the table ; while, at intervals, 
he will not forget to sow Mignionette for winter 
flowering, and such biennials is may have been be- 
fore neglected. 



L«aDO«<— Pnatc4 by U. Fkanci*. «. White Hon* Lana. Miln Kml.— f ubli«fa«<l by W. BBiriAUt. 1 1 . Pil«mu«ter Rm>. 
(which aze auiwoiad Hoalhlyjlo be wldicssed lo On EtUWr, at V. CotlaK« Grove. Mils Cad fiM«, 




THE 



MAGAZINE OF SCIENCE, 

"SLnti School of ^m. 
123] 



SATURDAY. AUGlfST 7, 1841. 



\Ud. 





w X 



^.U 



f^j^ 



NEW ELECTRO-MAGNETIC ENGINE. 



L. lU.-^-MO, XIX, 



i 



14G 



MAGAZINE OF SCIENCE. 



Steam Supttrtedtui, Am Anount iff iht nrmly- 

tMmtteH Etectro.mnynf'tic Eupine, for the PfO- 
fminon nj Jjirttmultveji, SlitjtM, MUlu, i,'c. : and 
cho apftUcabie to the Ptttcc*»m nf Syinniny^ 
TStming, Ormdimg, Saving, PoliKfiing, Vi*., 
mid every Speciet qf Methaucai Moretnent. 
Price 2m. , jHign 36. 
Such is tbe lille of « tery small vork, pretty (fcne- 
rftlly dUtributcd throughout London, h is a truni- 
Ution from the Germin. Ufwn lookiog into this 
work we expected something exceedingly new, and 
■t the same time exroedingly excellent. We were 
•oinewbut disop{Hjtuted, therefore, in findinf^ that it 
gives a deacription of the first mschinc, invented 
two or three years ago by M. Jacobi. Without itit 
describing other inachiooi of more simplicity, grcBter 
power, and of h:ss weight and expense ; besidea 
wholly lenvtng out the account of Sir. Sturgeon**, 
and whatever else has been done in this country, re- 
lative to the tnnving of macfainea by cleclrD-mag* 
nelinn . This might hsve been eicosed in the original 
German work, but it is in some degree to be regretted 
that this small treatise was not made more useful by 
introducing various matters of thia kind in notes by 
the truuUtor, who ia well able to bafc supplieU 
them. 

With this drawback the work Is good, giving on 
account of the princtjial parts of the reasouijig and 
experiments of M. Jncobi, who, whotevcr may be 
^e merits of others, must always hold a distinguished 
nnk among electricians. WV give some of the il> 
Ittstrattvo cuts, and iho fallowing extracts, explana- 
tory of thrm. from the book iUelf, trusting that 
those who are interested, will, by purchasing the 
work, (which may be had of any bookKllcr in 
London,} glean from it those unerhog principles of 
science and fact, which will assist in thpir own en- 
deavours to understand, and it may be to construct 
some simpUficaiiun of M. Jacobi's invention. 

** The ppneipal figure of the cut, (No. 1,) repre- 
sents A magnetical apparatus, in which eight bars, 
(four bars of soft iron in the shape of horse-sboei.) 
are symmetrically attached to a wooden frsme, re- 
volving round a horixontal axle. A, and eight others 
similar, arrnnged on a sufficiently strong fixed frame. 
The arrangement of tbe bars admits of every |>oa- 
aible variety, it being only nerewary that they he 
oymmetrically arranged, and that their poles shall 
past each other as cloacly os )Kissible. Since iu all 
probability tiio centre of the mogneticaJ gravity is 
situated at some little distance from tlie extremity, 
as is the case with the ordinary magnetic bars, it 
would be better to arrange it so that the axes of the 
oylindrical bars should be at right angles to ouo 
another, instead of parallel, as in the figure. The 
form given in the plate is attended with some other 
inconvunicDces, as regards the formation of tlie spi- 
ral line* of copper wire, which must be first bent 
over another cylinder of the some dimensions. 
These spirali must be quite close to the cylinder, 
but be preserved from contact with it by being 
wrapped in silk, for tbe sake of isolation. 

'■ The several bars attached to the moveable and 
stationary frames ore then converted into electro- 
magnets, by being encircled by the wire of a voltaic 
battery, and their extremities are north and south 
poles alternately. If, then, a slight impulse be 
given to the moveable frame, it will continue to re- 
volve in the direction given, nnlil the contrary poles 
come opposite one another; after a few oscillations 
the iQotioa would be snspcndeil, were it not, that, 



by means of an ingenious contrivance t>f Jaca^K 
which he terms the cfrMrNU/tf/or, the moment di»- 
similar yoWt rotuc oppusitr one another, the |)ohM 
of the moveable or stationary bars arc rcverasd, 
and thus the original conditions of motion on n* 
newed. 

** The cnt No. 3. gives a front new of the bara. tad 
No. 2, a side view of tlu; commutator. There ar* 
four plates of copper attachrd to the rotatory axlo, 
which likewise bears the frame on which the electiv* 
muf^iets are fastened ; the plates are connected fary 
coppur tulxrs, two and two, and each pair nf pUtM 
perfectly separated from the other by the interposU 
tioQ uf ■ hollow axle of jupnoued wood, or any similar 
isolating substance. The edge of each plate la oo- 
curately divided into eight parts, foar of whidi, 
U H U 11, (No. 2.) arc cut out, and duly filled with 
ebony, so that the sectors and the metal present a 
perfectly even surface. The plates are so arraogeU 
on the axk, that the sectors of wood and metal alter* 
nately correspond, as exhibited by the figure, No. ]> 
C C ore copper levers, very moveable round their 
axes, and servmg to conduct the current of the TolBsie 
battery. Each lever is shaped like a bammvol 
the end, which rests on a corresponding pUlcr* 
The shorter arm is bent, and dips into the vessel K 
filled with mercury. These Te«ecls (for thero on 
four of them) are, as appears by the pUte, con* 
nectcd with one another by means of a copper win. 
*' The action of the cOTWiwufa^or will be uuw rtaJUy 
understood, llie levers are in constant cooueiioa 
with the plates, but touch the metallic and isolating 
parts alternately. As they readily move roand their 
axes, they Hy from the slightest mequality of stir- 
face, and the friction which is therrby cauard is very 
trifling. The spiral coiU, which encircle the move- 
able bars, are nnited to one wire, branches of wbteh 
ore soldered to the pairs of pUles uf the commo* 
tator. The other spirals, endrcling the fixed ban, 
are similarly joined, and the ends dip.* the one Into 
a vessel uf quicksilver, which is connected with lb* 
voltaic apparatus, and the other into one of tbs 
vessels of the commutator. Thus, by means of lbs 
commutator, the whole sixteen spirals form bwtoM 
connecting wire. The voltaic apparstoa cooaisU ttf 
four troughs of copper, into which four ploCva el 
xino dip. As soon as the lai^ wooden fnmt is 
turned by the power of the voltaic pile, the con- 
mutator, which is attached to the same axis, wiUbf 
likewise set in motion, ami thus the reversal of 9kt 
poles effected by raeans of the modune itccif, pro- 
vided that the commutation plates be so coostraclal 
that the extremities of the levers shall pass tnm 
one sector to the other. 

" In September, 1837, by advice of the Mloistef of 
Pablic Instruction in Kuseia. a commission, cua- 
sistingof RearAdminUvoo iCruseostrnt, the Acadv- 
micians. Fobs, Ostragrad^ki, Ktipfer, and Ijoatt 
Colonel Sololewak), and Licutenant-Culonei Bnnl- 
aphock were appointed, under the guidance of Pro- 
fessor Jacobi, of Dorpat, with a view to endeavgor, 
by experiment, to render electro-magnetism appli- 
cable to the working of machinery, and particularly 
to tbe propulsion of ships. The object of this com* 
miaitiiiu appears in part obtained, as on the 2otb of 
September, lH3ti, a vessel was set in motion on ths 
Neva, An eight-otred gtlley, such oi is osool im 

In oar rul we iisvc omltlad tbs galvsole b&U«ry, it prn- 
•«nl)n| nulhlnjf pi>ruIUr, The two wire*. N and V. ar> tli«H« 
which profiM'd to U. od« of tbmm ramUif rroni lite fitAl tiw, 
theoLhirr frvra Ibe CKiDtnutstar, oc Irmn Um siovval»t« ban 

througb the CDniniutuiur. 



MAGAZINE OF SCIENCE. 



147 



the Ti«rr, WIS placed at the disposal of the commiit- 
' ' rii Irntfth, an<l "J in breadth; it wna 
J ii paddlM flimilnr to those of a itrom- 

1-^' > i. ..ti.i till! vnrioul flpparstiif vcre put cm 
botrJ. 'I"he insufficiency of many of the arranf;e- 
mencs which had beeo made, was then, for the first 
tftau, sp}>«rentf and io consequence, tbs first ex- 
penment was in n measure proportion ably nnsac- 
orvafui. It had been intandcd to moke experiments 
only in atiU water, but they succeded in propelling 
the veuci on the Neva, eren against the stream. The 
rpeed otttiiDed ia itill water was three Engltih mites 
per hour, ftnd would have been (greater liad the 
weight on board, which waa largo, \>ecn properly 
dbtrilmtetl throughoot the boat, which drew 2^ feet 
of water. The machine, when on board, occopied 
a vpace 12} feet Id breadth, and 2} in length. 

"Th< butit-TT consisted of 320 pairk of platea, ar- 
rtag«d along the sides of the boat, leaving imffictent 
room for tweWe persona. The whole battery could 
b« bromght into play only for a abort time, in con- 
nqftcnce of a trifling fauit in the connexion, which 
h wma im[>oHtible to correct on the spot. The con- 
moiptjon of zinc, or rather tbe production of vitriol 
of ttii£ per horse power, could not be exactly as- 
textaintd ; but it would appear from the ezperi- 
aaeala, that this ooald not be very considerable, in. 
aamach as the original weight of the zinc, being 4(K) 
•oanda, and presenting a surface of 'Jti sfiuare feet, 
ud decreased but 2( pounds in weight, during from 
two to tfaree months that the experimenti were 

ti'd. 

>vided tbo health of Professor Jaeobt allow 
Itim, he intends conatnictinK^ au electro- magnetic 
saiditne of 40 to SO-faonw power, and to adapt it to 
Ibe fkropaUion of a TeaaeL • • * 

** Dawt/npon, who has constnicted the moat pow- 
Wfol maehines propelled by cltfctro-mogDetism, ia 
•■id to have already applied some imalier ones to 
objrctfii such as the working of printing- 
principally of a few horse power. Daven- 
fOtt'a machines are, at preaent, the miMt powerful 
•■d aavple. (\ description is in a former part of 
lUrn'Maimne.) 

'• U'**r- rndebted foragrratimproTcmentin elec- 
ti rnachinea, to tlie mechanician 8tnehrcr, 

V' "bo bait constructed a macbine oi a 

mode), the perfect simplicity and easy construction 
of which will, In all probability, ensure its applica- 
tSnn in tiie room of all ulber moving poweni. It is 
worked at present but by four elements, each con- 
•^ a copper cylinder filled with vitriolic acid, 
a tine plate is hung, and sets a lathe in 
which is applied to the turning of small 
artirles. The expense of this power for twenty- 
foiir hours is one shilling, one hflf of which ia fully 
by the pore metallic copper which ia ob- 



** Sloehrer eonstTDCted this model last year on the 
plnriplct Laid down by Jacobi; and some time 
•fker, Wagrner, of Frankfort, constructed n similar 
Model, for which a reward of 100,000 (lurins was 
^aamntcred him by the German Diet, as soon as the 
plan -hould be carried out on a loi^ scale. 

" This execution on a large acale has, according to 

-*t icrounts, sutxecdrd most brilUiinlly ; for 

nil) is at present worked by cleclro-mng- 

:i Bftvaria, and this new power has alreudy 

. :he moat sanguine expectations. A loco- 

-:-„.... IS alao propelled by it. 

" It Is. thcrcfure, to be expected that eleotro- 
BSfaettam will soon play au inporCuiit part, and 




unrioestionably sapcrscde steam, which Is so much 
more dnogcroua and expensive, and «very other 
power witli which we are as yec acquainted. — 
Stoehrer is convinced that, with 100 sine elements, 
as above mentioned, (equal to 4b hor^c power,) he 
can propel a train of waggons with the usual num- 
ber of paBscngers, from Letpaic to Dresden on the 
railroqd, at an expense of hue six shiUinga, whilst 
the expense at present la about five pounds sterling. 

** Wc thus arrive at a standard of the extraordinary 
economy and power of these new mnchines : noC> 
withatauding Uieir immense power, thry can, never- 
thelefi«, be instantly stopped by a child ; nothing 
further bring necessary to btop the machine than to 
lift the connecting-rod out of the veaael. 

" The extent by which Uiia power may yet, and 
nuat in time, be perfcirted is sufficiently clear, from 
the fact of its being applicable, with the greatest 
advantage, for grinding, turning, spinning, and in* 
numerable other mechanical procesccs. 

"We feel, ilicrcfure, justified in calling the atten- 
tion of meohooica to thia novel power." 



ANALYSIS OF MINERAL WATERS. 

( Hemmed frvm pofje 1 2$. > 

9. Sulphuric acid exists in waters that form a 
prrripitate with the following solutions : — murifttc, 
nitrate, or acetate of barytes, strontian, or lime, or 
nitrate or acetate of lead. Of these, the most pow- 
erful by far is muriate of barytes, which ia cap&ble 
of detecting the presence of sulphuric add uncom- 
bined, when it does not exceed the uiillioiith part 
of the water. Acetate of lead ia next in point of 
power. Tbo muriatea are more powerful than the 
nitrates. The calcareoos aalts nre least powerful. 
All these tests are copable of indicating a moch 
smaller proportion of unoombined sulphuric acid, 
than when it is combined with a base. To render 
muriate of bnrytes n certain teat of sulphuric acid, 
the fullowiDjj; precautions meat be observed :— The 
muriate must be diluted ; Che alkalis or alkaline 
carbonates, if the water contain any. must be pre- 
viously aaturatod with muriatic acid ; the precipi- 
tate mast be insoluble in mnriatio acid ; if boraelc 
acid be suspected, muriate of strontian miut be 
tried, which is not precipitated by boradc ai^d.— 
The hydro -sulphnrets precipitate barytic solutioni, 
but their presence Is easily discovered by tire smell. 

10. Muriatic acid is detected by nitrate of silver, 
which occasions a white precipitate, or a cloud, in 
water rontnining an exceedingly minute portion of 
this acid. To render this test certain, the following 
precautions are necessary :— The alkalis or car- 
bonates must be previously saturated with nitric 
acid. Sulphuric acid, if any bo present, oaust be 
previously removed by means of nitrate of barytes. 
The precipitate must be insoluble in nitric ocid.— 
PfafTsayv, that the mild nitrate of mercury is the 
motl senaiblt^ test of muriatic acid ; and the. preci- 
pitate is not soluble in an exc&ta of any acid. 

11. Boracic acid is detected by means of acetate 
of lead, with which it forma a precipitate insoluble in 
acetic acid. But to render this test certain, the 
alkalis and earths must be previously snturulcd with 
acetic acid, and the sulphuric and muriatic acids 
removed by means of ocetate uf strontian and acetate 
of allvcr. 

1 2. Barytea is detected by the insoluble white 
precipitate, which it forms with diluted sulphuric 
acid. 



^ 



149 



MAGAZINE OF SCIENCE. 




13. Lime is detected by meaos of oxalic acid, 
which occuioDS a white prvcijiitate in water con- 
taining a very minute proportion of this eitrth. To 
render this teat deriilve, the following precaations 
are necenary : — ^The niiDeral oclils, if any be piv- 
sent, moat be previously saturated with an alkali. 
Barytei, if any be pre«ent, roust be previously re- 
moTed by means of sulphuric acid. Oxnlic acid 
precipicatea magocsta very slowly, whereas it preci- 
pitatei lioie instaally. 

M. Silcx may be adcertained by eraporattng a 
portion of water to dryness, and re-disiulving the 
precipitate iu muriatic acid. The sUex remaius be- 
hind undiMolved. 

By these means we may detect th« presence of 
the different substances commonly found in waters ; 
but 05 they are generally combined so as to form 
salts, it is necessary wo should know what tbeee 
combinations are. This is a more difficult ta»k, 
which Mr. Kirwon teaches us to accomplish by the 
fbllowiog^ methods : — 

1. To ascertain the presence of the different sul- 
phates. 

The sulphates which occur in water are seven ; — 
hot one of these, namely, tnlphate i}f cupptr, is so 
uncommon, that it may be excluded altogether. — 
The same remark applies to sulphate of ammonia. 
It la almost onneccssary to observe, that no sul- 
phate need be looked for, unless both its acid and 
base have been previously detected in the water. 

Sulphate of soda may be detected by the follow- 
ing method : — Free the water to be examined of alt 
earthy sulphates, by craporating it to one-half, and 
adding lime-water as long ej any precipitate appean. 
By these means the earths will nil be precipitated 
except lime, and the only remaining earthy sul- 
phate will be gulphnte of lime, which will be sepa> 
rated by evaporating the liquid till it becomes con- 
centrated, and then dropping into it a little alcohol, 
ami, ntitx filtration, adding a little oxalic acid. 

V^ith the water thus purified, mix solution of 
lime. If a precipitate appear, either immediately 
or on the addition of a little alcohol, it is a proof, 
that sulphate of potash or of soda is present. Which 
of the two may be determined, by mixing some of 
the purified water with acetate of hurylea. Sul- 
phate of barytes precipitates. Filter and evnporata 
to dryness. Diigest the residuum in nloohol. It 
will dissolve the alkahoe acetate. Evaporate to 
dryness, and the dry salt will deli([ue8ce if it be 
acetate of potaab, but effloresce if it be acetate of 
loda. 

Sulphate of lime may be detected by evaporating 
the water suspected to contain it to a few ounces. 
A precipitate appears, which, if it be sulphate of 
lime, is soluble in 500 parts of water ; and the 
solution aifords n precipitate with the muriate of 
barytea. oxalic acid, carbouute of mu^csia, and 
alcohol. 

Alum may be detected by mixing carbonate of 
lime with the water suftpe[;tc:d to cuutaln it. If a 
precipitate appear, it indicates the presence of 
alum, or at least of sulphate of alumina ; provided 
the water contain<f no muriate of harytcs or roetaUic 
sulphates. The tint of these salts is incompatible 
with alum. The second may be removed by the 
alkaline prusBidtea. M hen a precipitate is produced 
in water by muriate uf lime, carbonate of licne. and 
murinte of maj^nL-sia, we may conclude that it con- 
tains nlum or sulphate of alumina. 

Nulphate of magnesia may be detected by means 
of bydroculphuret of sLronlian, which ocouioos an 



immediste precipitate with Oils salt, and with no 
other ; provided the water be previously deprived 
of alum, if any ho present, by means of carbonsto 
of lime, and provided also (hat it contains no ob* 
combined acid. 

Sulphate of iron is precipitated firom witter by 
alcohol, and then it may be easily recognised by &M 
properties. 

2. To ascertain the presence of the different 
muriates. 

The murintcs found in waters amount to e^fat, 
or to nine if muriate of iron be included. The most 
common by f»r is muriate of soda. 

Muriate uf soda and of potash may be detected 
by the following method: — Separate the sulphuric 
acid by alcohol and nitrate of barytes. Decompow 
the earthy nitrBtcs and mariatca by adding sal- 
phuric acid. Expel the excess of muriatio aai 
nitric acids by heat. Separate the snlphace* tbu 
formed by alcohol and barytes water. The watsTi 
thus purified, can contain nothing but olkBlino 
nitrates mid muriates. If it form a precipitate with 
ocetste of silver, we may conclude, that it coutaiu 
muriate of soda or of potash. To ascertain which, 
evaporate the liquid thus precipitated to dr7n«ift.'— 
Dissolve the acetate in alcohol, and again evaporate 
to dryness. The salt will deliquesce, if it be sretHe 
of potash ; but efRoresce if it be acetate of sods. 

Muriste of barytes may \k drtected by snlphurie 
wad, u it is the only borytio salt hitherto fonad \m 



Mnrinte of lime mny be detected by the following 
method : — Free the water from sulphate of lime 
and other sulphates, by evaporatiog it to a few 
onnces, mixing it with alcohol, and adding lut of 
all nicrate of lurytes, as long as any precipitate ep- 
pears. Filter the water; evaporate to drToeu?^ 
treat the dry mass with alcohol ; evaporate Cfao el- 
oohol to dryness ; and dissolve the residuum 1« 
water. If this solution give a precipitate with oo^ 
tate of silver and oxalic acid, it may contain muriate 
uf lime. It must contata it in that case, if, after 
being treated with carbonate of lime, it give vo 
precipitate with ammonia. If the liquid in the rt- 
ceivcr give a precipitate with nitrate of silver, mu- 
riate of lime existed in the water. 

Muriate of magnesia muy be detected by sepe* 
rating all tlie sulphuric acid by means of nitrate of 
barytes. FUter, evaporate to dryness, and treit 
the dry mass with alcohol. Evaporate the alcohoU* 
Bolutioa to dryness, and dissolve the rcsidDnai ta 
water. Tbo muriate of magnesia, if the water am* 
taiued any, will be found in this solution. Leive 
suppose that, by the tests formerly described, the 
presence of muriatic acid and mogneeia, in llui 
Bolutiun, has beett ascertained. In that caae» \i 
carbonate uf lime afford no precipitate, and if s«U 
phuric acid and evaporation. togi:thcr with the ad- 
dition of a little alcohol, occasion uo precipitatO, 
the magnesia is to be separated by the oxalic add 
and alcohol, and the acid with which it was uniXcd 
is to he distilled off. If the liquid in the reiorv 
give a precipitate with nitrate of silver, tlic water 
contains muriAte of magnesia. 

Muriate of alumina may be discovered by Hta- 
rating the water, if it contain on excess of alkaH, 
with nitric acid, and by separating the sulfihurut 
acid by mcaus of nitrate of barytes. If th'' li >ii»4 
thus purified, give a precipiUile with eaii 
lime, it contains muriate of alumiua. TbL 
of iron or of mnnganese, if any be presvnt, i* «a«i> 
decomposed, and ihv icon prccipitAtod by this salt. 



MAGAZINE OF SCIENCE. . 



149 



MUt« may be diwiilTed ia muriALlc acid, 
imiiia. iroHt and mnDgrine<e, if they be pre- 
be leparstcd by the rules laid down below, 
■accrtata the pretence of the different 
U The iiitratei but seldom occur in waters ; 
en tbey do, they may be delecUd by the ful- 
rcaiilta : — 

.line nitrates may be detected by freeing the 
examiocd from Hilphurio acid by mcana of 
of barytcs, and from tauriatjc acid by acetate 
r. Evaporate the filtered liijuid, and tn'aC 
mau with alcohol ; what the alcohol leaves 
uisC only of the oJkaline nitrates and acetate 
}. Dtuolre it la water. If carbonata uf 
da occasioo a precipitate, lime is present.— 
le the lime by means of carbonate of mag. 
fMter and evaporate to dryness, and treat 
)5d mass with alcohol. The alcohol now 
only the alkaline nitrates, which may be 
racogoiied, and distingmsbcd bj their re- 
B properties. 

■Ic of Umc. To detect this aalli conceotrate 
W« and mix it with alcohol to separate the 
HL Filter, and distil off the alcohol; then 
e the muriatic acid by acetate uf silver.— 
eraporatc to dryness, and dissolve the resi- 
a alcohol. Evaporate to dryness, and dis- 
se dry mass In water. If this last solulion 
t the presence of lime by the usual teats, the 
vmtxtuetl oltnitc of lime. 
rtcct nitrate of magnesia, the water ts to be 
rom sulphates and muriates exactly as de- 
la the last pangmph. The liquid, thus 
l« ia to be evaporated to dryness, and the 
■1 Created with oIcohoL The alcoholic solu' 
to be evaporattrd to dryness, auil the dry 
bftolved in water. To this solutiua potash 
I added, «s long as any precipitoCe appears. 
lution, filtered, and a^oin evaporated tv dry- 
I to be treated with alcohol. If iC Icuve a 
m considtuig uf nitrate (the only residuum 
iK can Icare;, the water contained nitrate of 
HU 

fTobeeontinutdJ 

THE PHILOSOPHER'S STONE. 

lilosopber's stone (formerly called tAe trori, 
of ejccelleoce, or chty^opta, the IrauBmula- 
the bas« and imperfect mctiUs into guld ur 
has, since time imiuemorial, beeu au object 
:h the attention of miiltitadcs of peu[tlc, 
reraed in chemistry or scarcely initiated in 
ence, has been directed, llie vulgar once 
t tliat it was the sole object of chemistry ; — 
vast, indeed, be allowed that it was in some 
e the fault of those who first cultivntcd that 
mtieh of philosophy : there were few of them 
1 aot sufler IhemicUes tu be bliudeil by the 
of attempting to make gold. 
at pre«euc very few people ore Infatuated 
le philosopbcr'a stone ; at any rate none of 
ij[htencd chemists employ themselves with 
ins of making gold ; but formerly there were 
lersoDS who, though tbey have scarcely an 
tha simplest oiH.Tatiuu^ of chemistry, wsj^tcd 
ma in vain attempts to regenerate tiiat pre- 
Bctal. Tbcy are often seen proceeding ot, 
and stiU imagining themselves on the point 
in the midat of poverty consoling 
with the sgreeuble idea, that this iudi- 
vucBcdcd by the posacasiou of im- 




mense treasures. They called themselves adrptt, 
because they pretend to have reached to the summit 
of philosophy, yuati mrntnam tapientiam adcpti ;— 
they spoke enigmatically and in an unintelligible 
manner, because mankind in general do not deserrv 
to possess such a secret. Filled with empty pride, 
they coat a sardonic smile of cootempt on the ra- 
tional chemists, and on those who endeavoured to 
deduce phenomena from clear and established prin- 
ciples. 

We might say tu the searchers after the philoso- 
pher's tttuoe, before attempting to make gold, first 
decompose and re-composo it ; for if there be any 
method of ascertaining and demonstrating the con- 
stituent principles of any substance, it is that of de* 
composiUuu and re- com position. We might say 
aUo to those alchemists, before you make for us 
the precious metAls, such us gold and silTer, make 
for us lead ; fur before you proceed to the most dtf- 
ticult, method re^iuires ttiat you should execute the 
easiest. But we are acquunted with no chemical 
operation whicli resolves either of these problems. 
Gold, as stubborn in regard to decomposition, as to 
compmilioD, always remains the same, in whatever 
manner it bo treated ; it is only more or less at- 
tenuated, but is never in the state uf calx. It Ims 
been kept for several years in fusion, without losing 
the least part pf its weight. 

But let OS near the alchemists, and learn what 
are their proteukioos ia regard to the formation of 
metals. 

According to them, metals are all formed of an 
earth, which they coll mercurial, but more or less 
mature, more or less mixed with lieturogeaeoua 
matters, so that tu convert the imperfect into the 
perfect metals, nothing was necessary but to free 
them from these heterogeneous mattertf and Co 
mature them. 

Ail this is rery fine : but who has proved the ex- 
istence of this mercurial earth ? who has proved 
that the dilTerence among metals consist* lo this 
greater or less maturity i by what means ia it to be 
produced? To these questions no solid answer can 
be giiven. 

According to other alchemists, mercury contains 
Ln principle all the perfect metals ; it has the 
sjilendourof them, and nearly the weight j it is even 
heavier than silver. If it is fluid and exceedingly 
volatile, it is because it is alloyed with impurities 
which degrade it. The question, then, ia to fix the 
mercury, by freeing it from thoHo properties. We 
should then have the mercury of the philosophers, 
which would require only a certain degree of baking 
to be brought to a red heat, and tlie re&ult would 
be gold ; brought to a white beat, it would furnish 
silver ; nay, this matter would have such an activity 
ou the impure parts of other metals, that by throw- 
ing a pinch of it into a crucible filled with melted 
lead, it would transmute it into silver or gold, ac- 
cording oji it had been carried to a white or red heat. 
Uut the great matter is, how to destroy the impuri- 
ties by which quicksilver ia debased, Aristeua, a 
celvbrated adept, tcadics us the process in the 
clearest manner, in his '* Code de Veritc.*' " Take,*' 
says he, "king Gabertin, and the princess Beyo, 
his tiiittrr, a young lady, beautiful, fair, and exceed- 
ingly delicate ; marry thera together, and Gobercin 
will die ulmo:it immediately. Be not, however, 
alarmed ; after eighty days, Gabertin will revive 
from his ashes, and become mure beautiful and 
more perfect than be was before bis death ; wiQ 
beget with Ucya a red child, more beautiful and 



150 



•MAGAZINE OF SCIENCE. 



i|>erfect than thcmMlres/' After this, mil uiy one 
pretend to *aj that the alchetntsti explain tiiem- 
flelves obBcnrrljr ? ^\llBt true adept, for there are 
true and ftlse* aud erery one thlnki himulf among 
the formrrt will uot evidently »ee in tliii allegory 
the whole proceaa of the fixat^n of mercury and of 
the powder of projection ? 

This Un^^e. and tbif aflectatton of obacnre 
■liegoriei, are no doubt very proper for making 
Ithese pretended adepta be cgniidered as finished 
•nd contemptible quacki, or, perhapi, as people 
vhose brains have been deranged by the beat of 
Ihnr fumacea. But the partisans of their researrhei 
iftnd foUiea allege pretended facta ; and It ia our busi- 
nrss to make them known. 

It is reluted that llelrctius, a physician and cele- 
brat4:d professor in UoUand, having declaimed one 
day with great Tiolcnce, in one of his lectures, 
•gainst the vanity and absurdity of pretending to 
nuke gold, was visited by on ;adept, who gave him 
a certain powder, a pinch of which, thrown into a 
crucible, filled with melted lead, would transform 
it ioto gold : that the learned Dutchman did so, 
and obtained from hia lead a considerable quantity 
of that metal. Hclvetias then hastened to find the 
adept ; but the latter had given him a false address, 
and woa not to be found ; for the chemiirta of this 
order never fail to disappear at the noment when 
tbey have given a proof of tbeir profound knowledge. 

The same thing occarred, it ii said, to the em- 
peror Ferdinand. Ao adept came to lum» and of- 
fered to transform mercury into gold. Mercury 
was pat into a crucible in the presence of the prince, 
and the adept having performed certain operations, 
[• button of gold was fonnd in the bottom of the 
veuel. Bat while those present were employed in 
examining aud astnytag the gold, the adept disap- 
peared, to the great regret of the emperor, who 
\«Ircady beheld in idea the immense treasures which 
'lie hoped to obtain by the acquisition of this grand 
aecret. 

At the Raic of the effects left by M. Geoffroy, in 
1777, thrre were three nails, which, as it was said, 
were a proof of the possibility of at least transmut- 
ing silver into a common metal, inch as iron. — 
They were the work, as aasertcd, of a celebrated 
adept, who wished to prove to Gcofrroy the posxl- 
bility uf the tntnsmatatioo of nietals. One of these 
nails was converted into siWcr, by being dipped in 
an appropriate liquor ; the head of the other only 
Fliaving beea dipped, the remainder of it was iron ; 
and the point of the third having been dipped, that 
part was aiWer, and the head iron. 

Notwithstanding these authorities, no one, of or- 
dinary judgement, can hsve a beUef in the philoBO- 
pher's stone. It is very probable, that in all 
these pretended tran a mutations, there was some de- 
oeption, even if the above accounts were true. 

However, tbenlchrmisU pretend that all the fnblee 
of antiquity are nothing else than the process of the 
grand work explained eymboUcally. The conquest 
of the golden fleece, the Trojan war, the events 
which followed it, and the whole mytliology. are only 
emblems of the cbryaopea, pntdently vtrilcd by the 
ancient philosophers, who did not wish that their 
■ecret, become common, should be employed to pro- 
duce on immense increase of the precious metals, 
which mast then have lost their value, and have 
ceased to be the medium of commerce among man- 
kind. The reader may sec, in « curious work by 
Dom Pernetty. entitled '* Lcs Fables Egypticnnes 
etCrecques," 3 voU. 8vo., including the " Dicti- 



onnaire Mjtho-hermetique,** how far baman 
maybe extended, to find an ecplanation of such 
But every thing muy be explained in the sa: 
ner. We have heard of an adept, in the Fi 
Saint Marceau, who, being pursusded that tl 
Koman history was a fiction. Intended Co 
chemical explanation of it, which would 
supplement to the Fables Egypticnnes et G 
We have even heard that the hiiitory of tlia 
of the Horotii and the Coriatii w&a'exp 
with an appearance of truth, capable of 
doubt whether that famous circnmatance 
Roman history ever really took place 





form 

thill 



PRINCIPLES OF CRYSTALLIZATll 

CnrsTALS occur very frequently in the 
kingdom, and have long attracted attention 
count of their great beauty and regularitj. 
the greater number of the salts likewiae 
crystalline form ; and as these substances are moSSf 
aolnbte in water, we have it in our power to gtvd 
the regnlar shape of crystals in some measnn l| 
pleaimre. It hu long been observed by cbeeotili 
and mineralogists, that there is a partscnlar (fan 
which every individual substance always affectawfaril 
it crystallizes : this indeed is considered as one dj 
the best marks for diatinguishing one sobalnGl 
from another. Thus, common salt is observed t| 
assume the shape of a cube, and alum that of tl 
octahedron, consisting of two four-sided pyramidij 
applied base to base. Saltpetre atfects the 
a fiix-fiided prism ; and sulphate of magnesia 
s four*sided prism, whilst carbonate of lime ii 
found in the state of a rhomboid. Not that 
individual substance always uniformly 
the same form ; for this is liable to co 
variations from accidental drcumatances, 
are a certain number of forms pecolior to ei 
stance, nnd the crystal of that anhstnnce, 
case, adopts one or other of these fonoa, 
other; and thus comoioQ salt, when 
has always cither the figure of a cube, or oct 
or some figure reducible to these. 

To explain the caase of regular figures is a i 
task. Newton remarked, tiiat the particles of 
while in a state of solution, are imaged ia 
solvent in regular order, and at regular dist 
the consequence of which most be, that wb< 
force of cohesion becomes snfficicntly strong^ 
parate them from the solvent, they will 
combine in groups, composed of those 
which are nearest to each other. Now all thfti 
tides of the same body must be supposed taj 
the same figure; and the combination of a 
minate number of similar bodies must pt 
similar figures. Hauy hns made it exc 
probable that these integrant particles always 
bine in the same body in the Mme way ; that 
say, that the same faces, or the same edges, 
attach themselves together ; but that theae 
difi^erent crystals. This con scarcely be acconi 
for, without supposing that the particles of boAMl 
are endowed with a certain palarity which mska 
them attract one particle of another body, wl 
they repel the other parts. This polarit] 
explain the regularity of cryatalliiatiou, but] 
itself inexplicable. 

There are, however, Bome circnmstancw 
phenomena of crystallization, which llsny's 
docs not well explain, ond his viewf of the 
forou of crystalliccd bodies ore not tn ever] 



MAGAZINE OF SCIENCE. 



152 




tfootrovertibty established. Thus, a slice ofjtuor 
\mr, obtAined bf making two succesiive and 
kr&Uel Bcctioos, may be dividetl inio acute rhom* 
lids : bat these are Dot cbe phmitiTe forms of the 
Wr, becatur by the removal nf a tctrahe<lron from 
th extremity of the rhomboid, an octahedron is 
)tjuned. As the vbole mass, tlien, of the spor 
«y be divided into tetrahedra and octahedra, it 
■y be doubted which of these forms is to be coo- 
3c*<d u the jiritnittve one, espectaUy as neither of 
aoi can fill a ^trcn space without leaving vacuities, 
jt can they produce any arrangemcot sufficiently 
ftbl« to form the basis of a permanent crystal. 
Dr. WulUstou has given an eipoiition of another 
i«ir of cryitallixxtioo, (Philosoph. TransacL 1613.) 
t« bas proposed, that the primitive particles of 
iScA should be considered as spheres, which, by 
i«tual attraction, have assumed that arrangemeut 
hub brings them aa near as possible to each other. 
■ oumoer of similar balls are pressed togechsr 
Mmc plane, tliey form equilateral triangles 
other ; and if balls so placed were 
together, and afterwards broken asunder, 
gbt Uses in which they would be disposed 
,te, would form angles of CO'' with ea<^ 
bsr. A aioglt bull placed un this stratum would 
nA tbrw of the lower bails, and the planes 
IMlUag tbeir sarfaces would then include a r^olar 
tahedron. A square of four balls, with a single 
lU resting ofi the centre of each surface, would 
krvi an octahedron ; and on applying two other 
paU at opposite sides of tliis octahedron, the group 
bO represent the acute rhomboid. By this view, 
ibicft is highly ingenious, the difficulty of the 
vimitive form of fluor spar, above alluded to, is 
ibrikted. By oblate and oblong spheroids other 
arms may be assumed. 

Richard Phillipa. in treating on cohesive 
n. Bays :— The experiments of Mr. Donieli, 
Hauy, M. Link, and others, prove incon- 
, that all solids are varieties of crystallized 
while it requires a very slight exertion of 
to perceive that crystallized forms arc 
conscqucucss of atoms being packed 
by the action of the atoms of any elastic 
in which they ore immersed. The powers 
V art: varied only by the variable form of 
which are its patients during the process 
on and reduction of bulk. The patient 
therefore, are packed as it were by the in- 
activity of the elastic or fluid medium Id 
process takea place ; and they are dove- 
or bound together by the atoms in other 
ich mingle during the process, thereby 
united cryktahi, which crystals connUtuta 
dl ioUds, whose density, impenetrability, 
CQ of foreign action or motion, are 
•coOfding to the original form of their atoms, 
forms, and tho relative action of other 
acent atoms are, therefore, the sole causes 
hoa« phenomena of cohesion in bocUes. 
principles on which crystallization depends, 
seljr given by Cbaptal, as follows :— 
y docs not crystallizCi unless, by a previous 
the cohesion is broken, and tlie particles 
led fully and freely to exercise their re- 
at&nibcs. 

division may be edected by solution; the 

operated in water for salts ; in caloric 

and in alcohol for resins and certain 

• body Is disaoU ed in ono or the other of 



these fluids, the re-nnian of the particles dissolved 
in ejected by evaporation, or by lowering the tempe- 
rature of the liquid. 

Id those cases in which the soiutioo is performed 
by water or alcohol, evaporate till small crystals 
arc formed at the surface, or on the sides ; thcu 
suspend the operation, and as the liquid cools, a 
great quantity of salt in crystals will be precipitated. 
By evaporating the Liquid which lemaini, after re- 
moving the crystals on the top, you may obtain 
a second quantity of crystals, and extract all the 
liquid from tbe salt by successive operations. Bat 
if the dissolution is efleoted by caloric ainne, as in 
metailic fusions, and those of sulphur and pboft- 
phorus, other precautions arc necnasary to decido 
tbe crystallization. If you suffer a melted metal 
to cool, it will not fail to appear again, in codw- 
quence of the refrigeration, in its primitive form; 
exhibiting at the 6ame time some confused traces, 
or imperfect lineameots of crystallization, such as 
are observed in antimony and zinc. But if at the 
moment when tbe melted metal begins to harden, 
yon pierce the crust, and let out the metallic liquid 
contained within, the vacancy will be lined with 
regular crystals, which almost always present the 
cubic or octahedral form. Ueoca we may infer, 
that the metal in a moss is in reality an aggregation 
of orystals, and that the only method of giving it 
the reqcusite cohesion and ductility, is to beat it 
with the hammer, and to vWrf it. 

From what has been said concerning crysUl- 
lixation effected by evaporation and refrigeration, 
we may conclude, that, after having saturated a 
boiling liquid with any saline substance whatever, 
nothing more is necessary to obtain a deposit of 
crystals than to let it cool. We shall easily com- 
prehend all these phenomena, if we consider that 
there are then two liquids acting upon the salt, 
(water and caloric;) by taking away one of them, 
we cannot fail of having the whole of the salt, 
which it held in solution, for a precipitate. 

When the evaporation of the solvent proceeds 
slowly, the crystallization ts always more regular { 
the particles then unite and arrange themselves by 
virtue of their affinities ; but, on the contrary, 
when the evaporation is rapid, tho particles are 
precipitated ou each other, and there is nothing 
but confusion in their assemblage. 

The slowness of the evaporation not only deter- 
mines tho regularity of the forma, but likewise con- 
tributes to give volumn to the crystals. This wc 
observe daily in the saline solutions which we leave 
in a corner of our laboratories : it is dumoostrated 
too by all the operations of nstare, which forms in 
time, and by insenaiblo evaporation, saline and 
stony crystals, which it is impossible for us to 
imitate, because it is not in our power to cause ages 
to enter as elements into our operations. 

Rest is cqaalty necessary for the liquid, in order 
to obtain forms of great regularity ; uninterrupted 
agitation prevents all symmetrical arrangement ; it 
precipitates the orystals as fast as they are formed, 
and you obtain nothing, if £ may ao express myself, 
but the integral partidea of crystals. 

In tho arts we avail ourselves of the disturbance 
produced by agitation in liquids to procure crystals 
of extreme fineness. It \i by this method thuwe 
precipitate, in very small and delicate needles, the 
crystala of sulphate of soda, those of nitrate of 
potass, &o. 

It freqoeutly happens, thst a solution, though 
I complete, refuses to cry9t4llij[e ; in this case a 



152 



MAGAZINE OF SCIENCE. 



slight a^ution of the vessel somettmn decides tbe j 
crysUlliz'itioQ. Fahrenheit obflcrred, that, io tbii i 
circumfttonce, heat etcaped at the momeat of < 
agitation, which leenis to prove that the caloric 
was interposed betwwn the particles, and that 
notluDg but the alighce&t motioo waa wanting to 
disengage it. 

A crystal formed in water alwaja retains a more 
or leaa considerable portion of the liquid, and this 
is called the wafpr of cri/Atalh:afion. 

Tbe only cause of solution is, that the affinity of 
tbe liijuid overcoroea the cohesion which connects 
the particfes of the salt; but in jiroportion as the 
mass of the liquid diminishes by evaporation, its 
affinity of msis decreases, and tbat of the particles 
of the body dinolved increases, since they br^in to 
cotnbine with each^othrr. There mast. consc<|Upntly, 
be a moment at which the affinity of the salt over- 
pow^n thai of the liquid; and from this moment 
the salt which forma itself into crystals mast retain 
• portion of it. This water of crystal liution enters 
u a principle into the combination, dnce that 
liquid cannot be discovered either by the eye, or by 
Che touch, or by faygrometriral testa. 

This water of cry «talliia lion contributes to give 
to the crystal its form, tmnyiisrency, and cohesion. 
When it is disengaged by beat, these three characters 
almost always disappear. If, for example, you 
expose to heat a traniparent crystal of sulphate of 
Umc, you will instantly perceive the water to be* 
come volatilized and dissipated in vapour ; the 
crystal will lose its transparency, and be rendered 
friable and pulverulent. 

Simple lubstances, such as metaJa, certain earths, 
nlphar, phospborua. resins, and, in genera], nil 
inch bodies as are simple, and not soluble In water, 
crystuUize without retaining n seniiibic qusnttty of 
their solvent. Bat compound substances require 
to be dissolved in a liquid, that they may there 
acquire the portion necessary for tbe formation of 
their crystals. 



MEDICAL RECEIPTS. &c. 

JXsoh'f AniibilioHa Pith. — A nostrum com- 
posed of equal parts of aloes, scammony, rhubarb, 
and a little potaseio-tartratc of antimony made op 
with Castile soap, and of course, a powerful ca- 
thartic, and dcobstruent. 

l^rfyjropi.— a' nostrum obtained by distilling 
oil of nrpentiae in a glass retort till a red balsam 
reaoaina, which has also been called Balsam of I'nr- 
peDdDB. Or by distilling resin till a thick red oil 
comes over. Or by dlasolving 4 drams of flower of 
auljiliur in B ounces of oil of turpentine. 

Edinburtih Ointmfnt, for iU:b, and tetter, is pre- 
pared with laid, white hellebore, and h^drochlorale 
of unmoaia. 

Fincham't Purifying and DitinfecHnff Liquid. — 
A lotutton of chlunde of lime, requiring to be di- 
faited for use with -10 parts of water. 

Fiath. — A preparation sold by brewers* druggists, 
to color brandy and rum, and to give them Acti- 
tiow slnDgth. It is prepared by making an ex- 
tract of csyeune pepper or capsicam, and adding to 
it bornt sugar. 

Ford's BaUam of Horehtjvnd it a cough nostrnm, 
of which opium is the basis, being composed of 
•qua] parts of horehound and liqaonce root, infused 



in water, strained, and a double portion of aplril 
added to nine pints, to which liquor add 7 draiM df 
pure epiora, I oance of dried squills, C drams 
benzoin, 9 drams of camphor, 8 drams of anise* 
■eed, 1 f pound of honey ; digest and atrain. 

Pbiherffilt't Pilh. — A purgative noitrum, 
with equal proportions of aloes, acammooy, 
cynth, oiide of antimony, and aromatic 

Friar't BaUam, Compmmd Tincture of BensoSn, 
JfsuiV* DrApt, U'ade'M Drapa. — Take 2^ ounoM 
of benzoin. 1} ounce of storax strained, 10 drami 
uf balsam of Tolu, 5 drams of alol^, and 2 pints of 
rectified spirit; digest fourteen days, and filter.— 
It was long celebrated ai b styi^tic for the speedy 
cure of fresh wounds, cots, &c. ; hut nothing conU 
be more Improper, as it is stimulant and irritatlug. 

French R^, or Rouge, for the toilette. Tafcj 
1 ounce of genuine carmine, light in weight ai 
strong in color, mix it with very tinely-sifted 
powder, according to the shade irqnirod, and 
per the color by tbe eye, which will be 
laying the powder on aheeta of black paper. 

German Paste, for cage birds, is prepared by 
beating together 2 poont^ of poaie floor, 1 ptiaa) 
of blanched sweet almonds, 3 oances of freu I 
ter, and adding the yolks of two fmh tggt, an 
little honey and saffron ; then heat the mass gpsl!^^ 
and pass it through a sieve, to form it into frtim. 
If properly made it will keep good for half a ffsu. 

GilberVt AntUcfurbutic Dropr. — A di^wd 
preparation of bichloride of mercury. 

Godhold's Vegetable Baltam.—K noatrum eon* 
pMed of oxymel. with some coloring matter ■ 
perfume tn disguise it. Ttie specification of Go 
hold's patent, however, directs aeparate syrapl 
be made of 12 difierent herbs, many iif them ; 
ous, and then to be mixed with four different 
vini^r, oil of cinnamon. &c., and kept three^ 
before It is administered HI By a late trial it 
pears that the proprietor's profits have fallen frooi 
3,000/. to 50/. per annum. 

Oodfretf^t Cordial, — A popular nostrum, tka] 
basis of which is opium. Infuse 9 ounces of « 
fras, 1 ounce each of cartway, coriander, and ai 
seeds, in 6 pints of water, simmer till redneed Iftl 
4 pints, add 6 pounds of treacle, or coarse fU|Wt 
and boil for a few minutes. When cold, add 3 oi 
of tincture of opium or laudanum. 

Godfrey** Smelling Salta. — A nostnim pi 
by re-subliming sesqai-earbonate o( ammonia, with' 
carbonate of potass and alcolwl to moiacen it, m^xich 
forms carbonate of ammonia, of a very pt 
odour. 

Gregory^* Pounder. — Made with eqnal 
ginger, rhubarb, and calcined mogneda. K ll 
good stomachic in doses of 1 scruple or more* 

Grrn^ie't Cough ]>rnpn are a tincture of 
prepared with rectified spirit. A very onsafW 069- 
trnm. 

Gum Paste for Com^/s.— Soak an oance of gum 
tragacanth in half a pint of water, stirring it fr»- 
quently, till quite dissolved, which it will be io 3< 
hours, squcexe it through a coiu>e cloth by twist- 
ing, pat it into a mortar, and add four onncvi of 
Ireble-refined sugar, work it well till quite whitCi 
put it in a glazed earthen pan, with a wet doth ovtf 
it; when wanted, take some of this paste, workf 
and knead in it fine sifted sugar, till it Oecom 
without slicking to the fingers. When scented 
or colored, the aromatic materials arc worked in. 



ciJi^;rr"°*!^ w' iP" *""**•«"■ 5- ^^'l*"* H«i»t Lai*. Mil. E<id— Kubltalud by W. fiairriui. li. rsUrauvtot 
VtMWBuotMUdoi, (which are auwtred MouUily.j to be addrcucd to Uic Editor, at H. Cullaje Grow, Ulli- !;i« 



imI H<»n!. 



THE 



AGAZINE OF SCIENCE, 



^nd ^cdool of ^rt?. 



4.] 



SATUSOAT. AUGUST I< IB4I. 



[Urf. 




MAGAZINE OP SCIENCE. 



■ 



' EGYPTIAN AUCHITECTURE. 

Ik h work uf tlie nature of a geot^ral iniigaxtne it is 
im possible to treat effectively of so esteutfive s nib. 
j^ c( u vrcbitectuTc, without eiigrosniiti; too mach 
*(itcc, and diaiippointing those of our friends who 
look for far diffwcnt matter. We have, therefore. 
Ion); hesitated whi^ther to introdura the subject, 
and are still in doubt, if right, to iiursue the subject 
tfaroafb the Greek orders. Whether we do so or 
not, the noble and gignntic muses of masonry. 
niicd by the ancient Copts or Egyptians, during 
the time of the Pharoahs, with all their rode yet 
■pleodid ornaments, cannot but be intcrcsCin^, 
MpeciaUy upon reflection, that with, perhaps, the 
exoeption o( the cavern temples of India, of the 
times of which we have no account, the structures 
of Nitbia, of Thebea and Mem]ihiB, are the most 
•ncifnt records of human strength, skill, and taste, 
and those to which even the refined Greeks them- 
selves owed their fir»t ideas of architectural gran- 
deur and imposing outline. 

Well may the traveller of our day be astonished 
at the mogniAcence of the vast structures of an- 
cient Egypt ; its huge pyramids and proud tombs, 
which have long outlived the memory Cif the mif^hty 
kings whose oshea they contain; granite temples, 
OS extensive as towus, which inclose in their courts, 
or support upon their roofs, villages of the present 
Inhabitants: obeUslu covered with hieroglyphics; 
colossal statues; long avenues of sphinxes, &c. ; yet 
the art of huildhig aoujng them conaistcd of but few 
prlndiples ; far they did nut »eem to understanil thu 
use of the arch, all the apertures of thetr walls wrre 
covered with a single block of solid stone. Their 
domes or vaulte-d chambers (as in the great pyra- 
mid) were formed of stones, in horizontal courKe», 
projecting equally over each other, like inverted 
flights of steps. The roofs of some of their temples 
ore iodoed arch-shaped, but these ore only excava- 
tions out of the Bohd rock. Their walls were built 
of stones of enormous size, without cement. The 
removal and placing; of these huge materials would.. 
even at thifl day, almost bid dettaiice to the boldest 
and bi'st constituted of our mechanical inventions, 
thoi^h conducted with all the science of modem 
times. The stones of their edifices are for the roost 
part jointed and squared with the greatest accuracy ; 
the hieroglyphic carvings with which iheir walls 
and ceilings are charged, are all recessed, but pro- 
jecting in xplief from the bottoms or backs of the 
recesses. The forms of £gyi>tian temples and gates 
are generally truncated pyramids, crowned with a 
cove or large hollow moulding, and 611et above. — 
Bat tbe cut, illustrative of the present subject, will 
gire. perhaps, a better idea to the general reader of 
the details of Hgyptisti architecture than any verbal 
description. In the foregmiind of the right of the 
cat is a superb column, taken from the ruins of 
Dendera. or TVn/yrti. It will be seen how much 
labor has bei-'n expended upon a single column, yet 
the interior uf a temple might be called a forest of 
colnmnsi so numerous were they. The abacas (the 
capping stone nt the top) is very ]>ecuUar, bang 
nearly a cube in shupe; it is elaborately carved with 
filtolft and Rcrolls, and crowned with the winged 
globe, the emblem of eternity. The capital is four 
sided, each side braring the f4ce of Isis, the presld* 
ing deity uf tbe temple. Tbe shaft of tbe column 
is also richly curvett in compartments of hierogly- 
phics, of reeded work, and towards the busr. of the 
favorite lotus oroaineut, the emblem of beauty, and 



of the Nile, — in truth a national flower, as the 
is of England, snd the Uly of France. The 
purple, fragrant water lily called the lotus, may wail 
be the pride of the Egyptians, and if their repre- 
sentations of it have not an English artiat's tasted 
they at least show that these ])eopIt- could appredaU. 
if not express the beauty of their votive flower. The 
following is a more accurate detail of the lotoa m 
an architectural ornament: — 




It mast not be thought that all tbe columns of 
their buildings are formed upon one model. Ukr 
those of one of the Grecisn orders. In truUi lltfy 
vary both in proportion and ornaments The sltaft 
is often plain, more frequently retrded, or with round 
projecting ribs along it, and occaeionally fluted. Tbft 
abacus is often thin and iiiconsplcuuus, fometimeaa 
flat sculptured block. The capital is even yet mor« 
varied — a fine bell shape is extremely common, 
covered either with leaves or with hitToglyphics. 
The following examples, from tbe temple o( Coniatii 
may illustrate this ubservatluo. 




Immediately umler the column in the forej^rooMl 
ia A lion sphinx, for the sphinxes of Egypt mm 
various in character, sometiraes reprraeoting the 
lion simply, occasionally uniting the brute and The 
human forms -, and at other times being compoouded 
of different animals, or monitrous altoi^ther. Thry 
were placed in parallel rows, forming avrnnes «f 
great length, and constitating. together with tbt 
coloasi and the obelisks, tbe chief ritrrnal apprn* 
dsges of the Egyptian temple. In the left hand of 
the cut you see one of these obelisks. It is the 
representation of one uf the celebrated ones at Luxor, 
covered with hieroglyphics, and which was brought 
to, and is now erected in the French capital. At* 
thongh the baseless obelisk be not in its effect a 
striking object, when viewed in conjunction witii a 
large mass of buildings, it has paramount clumsi 
when regarded as a nnytp t/one, and con^derrd with 
reference to tbe labor and great meclianical skill. 
which must have been employed in detaching il 
from ila native quarry, in transferring it to its 
destined basement, and in raising it to its vertical 
position. 

At the back of the obelisk is a building com- 
posed of twin masses, riving on each side of t hr central 
door, which may be received as the ectabli^hed 
model of the gate that formed tlic entrance to any 
Egyptian buildings of considerable extent ; sad 



MAGAZINE OF SCIENCE. 



155 



whvrh from iu npenor loftmeo was by far the most 
' iK-iit md impoclng feature of tltc temple's 
r. The mott rnriom circumKUncc rt^pecling 
«t n liie dttplicate cbarnctcr, ghown in the Cwtn 
nolai or towers, (to which we hive already alluded,) 
file eotrancti being between th^m, lo ns to leave 
tbfUr individual solidity nnJiDpaircd. Thif ^te is 
not nierely to be considered u such, but it u also 
tiM nauai form ia which the front of the tcmplo 
SImI/ vat constructed. Two immeDBe piles of 
loUdtng tkperin^ upwards, with a gate between 
tlHon ; the salient angles or orriaea fioisbed with a 
large round torus or bead ; the suuinitt crowned 
with a drep hollow entablature or cornice, finiahed 
with a Bllct at top, and carved with longitudinal 
dMUinelfl, often arranged, aa in oar figure, like the 
Grecian Irigylph, constituted the characteristic form 
oT outline and proportion ; while the whole was 
oftentimes completely cohered with hieroglyphics, 

«n :' •! -Tinted with v&rions colors, so virid and 

i" that they remain fresh even in oar day, 

ari 1 - f^t ages of their construction and finish 

Boat tuTc been monDmrata equally of taste and 
labor; sod showing, in their contour and mojeaty, 
ttne of the greatest charms and requisites of archU 
Ucture, nmplicity. 

ORIGIN OF SPRINGS AND FOUNTAINS. 
It wuuld appear that the origin of fountains and 
•ftrinps craght not to have occaiioaed such a diver- 
aaty at opinions, as baa, for tome lime, prevslled 
BfDoag philosophera. An attentive consiileration 
of tbeae phenomena is sufficient to show that the 
ori^n of them '\& entirely owing to the raina wliicb 
cootioually moisten the surface of the globe, and 
whicJ], running over beds of earth, capable of pre- 
vrnting them from penetrating deeper, at length 
furre a passage to places which are lower. Every 
person, Indeed, must have observed, tliat the greater 
part of springs decrease io a considerable degree, 
whra a louff drought has prevailed ; that some of 
tiwtn ab»olnt<.')y dry up when this drought contiimt-i 
teo long ; that when the surface of tjic esrth has 
boen moistened with snow or rain, they are re- 
newed ; and that they increase almost in the same 
ynrgry^Ton as the waters become more abundant. 

"«0| hers, howerer, have ascribed the 
L' irtuns to a sublimation of the waters of 

tbr v^, Aiijcii, flowing into the bowels of the earth* 
lisc Dp in vapor, in ttie fissures of the rocks, and 
tlii>n.f tn, Ll^ down into cavities and reservoirs pre. 
are, from which they make their way 
Some have evtru gone so far as to 
i> H sort of subterranean alembics. 

nnjectures are entirely void of founda- 
water of the sea produced fountains 
r, it would lung ago have cboaked up, 
>™.i, the subterruoean conduiu through 
: is supposed to pass. Besides, the connt^r* 
-;ioh ia observed between the abundance of 
.J thst of the water of the greater part of 
.III, would not subsist ; as the internal dis. 
tiiUUon would take place whether it rained or not. 
It t* io be observed, alao, tliaC the water of springs 
aiwaya distils from above beds of clay, and not from 
Mmt them ; hut as these beds intercept the pas- 
aveof raponand water, the latter must necessarily 
come from above them. A sure method of destroy- 
tig a spring, is to pierce this bed ; but if the water 
eune fron below, ■ contrary effect would be pro- 
duced. 



\^*hat induced philosophers to have recoVt'^e to « 
cause BO remote, and so false, no doubt was their 
ima{;tning that rain water wa« not tutficirnC lo feed 
all the springs and rivers. But they were ccrl&^uly 
in an error ; for instead of rain water being .too 
amnll in quantity to answer that purpose, it sfet&.t 
mthcr difficult to conceive in what maancr it ia ei-» 
pended. This will be proved by the foUowaig cal- 
culation of Mariotte. 

This author observes that, according to eiperi- 
meittf which bavn been made, there falls annually 
on the fiurface of the earth about 19 inches of water. 
But to render his calculation stilt more convincing, 
he supposes only 15, which makes per square totae 
45 cubic feeti nod per square league of 2300 toisea 
in ench direction, 23BO&0000 cubic feet. 

But the rivers and springs which feed the Seine, 
before It arrives at the Pont-Royal at Paris, com- 
prehend an estcnt of territory, about fiO leagues in 
length, and 50 in breadth, which makes .1000 Icagnfs 
of superficial content ; by which, if 23yor)0000 be 
multiplied, we shall have far product 7H150f)OOOOn, 
for the cubic feet of water, which falls, at the lowest 
estimntion, on the above extent of territory. 

Let OS now esamine the quantity of water anna> 
ally furnished by the Seine. This river, above the 
Pont-Hoyul, when at itd mean height, is 400 feet in 
breadth, and ;) in depth. The velocity of the water, 
when the river is in this state, may be ealimaCed at 
100 feet per minute, taking a mean between the 
velocity at the surface and that at the bottom. If 
the product of 400 feet in breadth, by 5 in depth, 
or 2000 squnre feet, be multiplied by 100 feet, we 
shall have 200000 cubic feet, for tlie qtiantity of 
water which passes in a minute through thnt section 
of the Seine, above tho Pont-Royal. The quantity 
then in nn hour will be 120(10000 ; in 24 hours, 
288000000; aud in a year, 10.1120000000 cubic 
feel. But this is not the seventh part of the water 
which, as above eeen, falls on the extent of country 
that supplies the Seine. 

But how shall we dispose of the remainder of this 
water ? The answer is easy : the rivers, rivulets, 
and ponds, lose a considerable quantity of water by 
evaporation ; and a prodigious quantity is employed 
for the nutrition of plants. 

Moriutte mokes a calculation also of the water 
which ought lo be furnished naturally by a spring 
that issues a little below the summit of Montraartre, 
and which is fed by an extent of ground 300 toisea 
in length, and 100 in breadth; making a surface of 
30000 square toisea. At the rate of 18 inches for 
the annual quantity of rain, the quantity which falls 
on tliAt extent will amount to 1620000 cubic feec 
But a considerable part of this water, perhaps three- 
fourths, immcdiatrly runs off: so that no more than 
40^000 forces its way through the earth and eaody 
soil, till it meets with a bed of clay at the depth of 
two or three feet, from which it flows to the month 
of the fnunluin, and feeds it. If 405000 therefara 
be divided by 3G.'>, the quotient will be 1 1 00 cubic feet 
of water, which it ought to furnish daily, or about 
3Hr>UU French pinU ; which makes about 1600 
pints per hour, or 27 pints per minute. Such is 
nearly the produce of this spring. 

An objection, founded on ho ftperiraent of 
M. de la Hire, described in the mtmoirs of the 
" Academy of Sciences,*^ for the year 17011, is, com- 
monly made In thia idea respecting the origin of 
springs. This philosopher having canaed a pit to 
be dug in a field, to the depth of 2 ftret, found no 
traces of moisture ; from which some conclude that 



MAGAZINE OF SCIENCE. 



the nln witer flowi only over tbe lurfttce, tad doc* 
not, in any manner, contribute to the origin of 
BpringB. 

Bat this experiment 1b of no weight, aa it ii con- 
tradicted by a thousand contrary instance*. EvBry 
one VnowB that water, in Yorious pUcea, ooxea from 
the roofa of caverns and subterranean passages : it 
is this water which, after penetrating the earth, and 
flowing between the joints of stones, produces stn- 
loctites, and other stony cnncrctions. It is, there- 
fore, fiilae that rain water never penctrntes beyond 
the depth of a few feet. The fact, ohserred by M. 
de la Hire, was a particular case, from which it was 
wrong to deduce a general consequence. 

Il ia objected also, that water is sometime* col- 
le^rted at heights at which it is impossible that the 
rain water could give birth to a spring. To tliis it 
may be replied, that if the ground, where theae 
coUecliona of water exist, be eiamined, it will 
always be fonnd that they are produced by rain or 
melted snow ; that these places on the sunimiu of 
mountains are only a kind of funnels, which collect 
the waters of aome neighbouring plain, continually 
maintained by the rain or snow, oifiisted by the 
Itnall eraporation which talcee place, in consequence 
of the rarity of the air. It is, therefore, evident to 
every rational mind, that the origin of springs and 
fjnntains can be ascribed to no other cause, than 
t*u nin water and snow which have been collected. 

BOTANICAL NOTICES. 
nirnoDUCTiTK organs of pLA>rra. 
Tii« reproductive organi of pbiraogamous, or 
flowering pluU, are the flowers and the fmit. 
beoanae theae parU are of necessity in the prepa- 
ration, the maturing, and defending the seed. 

Both tbe flower and the fruit consist of serveral 
parts : for example, in the common primroee tiierc 
is outside of all a green cup, which incloses the 
rest of the flower— this is ihe calyr. Within tlio 
calyx is a colored leafy part, called the cortiUa. 
These two partfl together ore the Jloral enrelopeM. 
Still more inwards are a number of colored threads, 
with a knob at the cod of each— these are Mtametta, 
Innermost of all is a green swellcd-out body, called 
B jfointal or putU, which is either the young seed 
vessel or leads to it ; and the part of the stalk upon 
which the whole of these organs are placed is tbe 
receptecle. The manner in which flowers grow 
together or upon the stalk which bears them, is 
called their infioretemee, and the folding up of the 
diflercut parts of the flower before oi)ening ia called 
their ipxiivation. 

Tbe following cut will enable tlie student clearly 
to understand the namre.iwsition.and usual character 
of the reproductive organs, as eiempUfied in tbe 
cowshp : — 



A. Show* the Influcvaccoce Of mode of (loweriin. B. Tim 
nUvatlov or foldlof op of Uwcalyx C. 1 he caIvi nrour^ 
I>. ThP nstivation of lli» corolla. E. Tli*' i-inoll* i»BKr»w. 
F ThfcornlUopeii«ltoihowtlwllve«tajDnrf «i. AMaa^ 
mnpufuKt. with sooM gnUu of poMca »»> tb« ittW w( IL 
IL Tbe pbuL I. Tbe tUflma or top of tb« ityltt, niagnlftM 
J. Tha atad vwstl cot opan lenjAiriit. K- A w«d col oiW> 
to ibow tba aiabryo lyiof acroai IL 

The re-prodoctJTe OT:gana vary in shape, relntife 
itse, and method of attachment to each other, oo 
leas tlian do the roots, leaves, 0tc. Sometime! ooa 
or other of them is deficient — in different easea mors 
than one : thua a flower may want calys or corolbl, 
or both, when it would be called incomplete^ or ft 
may have all theae organs, and be complete. Ocoa- 
sionally one part is redundant, or of onnatunl 
form or riae, in which case the flowera become 
monitrowt. Tbua cultivation, injury, exccM of 
food, and many other causes, make such grast 
alteraliona in the structure, and stiU more often 
in the habit or appearance of a plant, that It b 
sometimes scarcely possible to recognise the altered 
form. However greatly variations of this kind may 
contribute to the beauty of the flower, or the utility 
of the fruit, yet by the botanist such changlinga 
must he disregarded as unnaturaL The hen and 
chicken daisy, the hosc-tn-hose polyanthui, a.nd all 
doable flowers, are in this condition. Even " tbe 
queen of our gardens,** the elegant rose Itself, is to 
be considered but as a vegetable monster, uo- 
courteous as the term may seem, becanae cnltaxt 
has increased its moss, multiplied Its petals, bedglil- 
ened its colors, and it therefore no longer bears in 
OUT gardens those simple 6owcrs with which natuic 
investefl it. 

Calyx. — The outer part of every complete flower 
bears the name of calyx, whatever may be its fllie, 
form, or color, The general use of this organ it 
to defend the more delicate parts of the flower from 
injury, when in their young and unfolded state. 

A calyx consists, in its usual state, of a leai^ 
green cup, more or less cut and divided. Hit 
different partfl or Icavea of which it connats v* 
colled sepals, and it often takes its name firom &■ 
number of these aepals. Thus, in tbe primroae It 
is jHonosepalotui, (1,) — that is, oue-leaved. In tbt 
poppy, disepalouM, (2,) — or conMsting of two 
leaves. It may also consist of three sepaU, (3.) u 
in the pUewort. Pour sepals, as in the cabbw(e, 
((.) It is 5, 6, 8, to, sepalrd in ntbcr plants, 
when its name would be appropriate to thcM 
numbers. 





1 s » 

It ia tuboUr, lipped, puffed out, ribbed, api 
notched, or entire. If it fall off when the ' 
opens, it is fugacioug—'-d it drop with the rest 
the flower, it is eaducotie—M it remain until the 
fruit is ripe, it is pertitteut. When situated abort 
the fruit, ss in the rose, it is coiled eupehor, (I,) 
when under tbe fruit, as ha the mallow, U 
ir^erior, (2.) 





MAGAZINE OF SCIENCE. 



157 



OQgk penutent csljrcca remain afu^ tbc time 
-erin^a it U gcDcrelly in a dry and withered 
»artkalarlj in those which ore suptrior ; and 
iaieniir, although they retain their green 
nd liTiBg texture longcri yet it ia not often 
ej coQtinae growing ahcr that period. In 
tlanta, however, it is diiTerent, for the calyx 
r« during all the time of the fruit rii>eniag — 
iitration of which tbc curioiuly-eolBrged 
i of tlie nictmdra phyaafodrt, and tlie bng- 
cutjx of the winter cherry may be referred 
reciaUy as they add «o greatly to the beauty 
fruit of theae and limilar plants. The calyx 
beobane Is another of a most beantiful and 
r form. It is also to be observed, that the 

• ofbm colored, as in the fuschla it is of a 
letDtiAil scarlet. When a flower has but one 
pe to its stameni, we must consider that a 

whaterer may be its color or form. The 
lily, the gsndy tulip, and the golden crocos, 
icir beaatj to thrir colored calyces ; nnless 

• as some botauists have doDCi we consider 
M fieriantAif, that is, a covering, which par* 
if Che position of a calyx and the character 

otlA. — The corolla is that part of the flower 
is next within the calyx, and between that 
le ttamena. It is generally the most brightly- 
d of the floral envelopes ; thus, the red leares 
i rote, the yellow of the buttercup, and the 
tt tbe bell flower, constitute the rarious 
K of those plants. A corolla may consist of 
oe leaf or petai, as it is more properly called, 
the form ^ this gives it an appropriate name ; 
nay be of •erenl petals, when their arrange- 
■nd thicVnem serve as marks of distinction. 
the Tsrions petals or divisions of a corolla 
lite, jt is said to be rtffutat — if noti irretptl^r. 
wumopetaiotu or onc-petaUed coroUc, the 

rU called the tu6e — the upper expanded 
Kmh, and where these join one another, 
Oii^JI or ikroai. They are either campanuhte 
^t-tAaptd, (1.) as in the bl uc -be 11— yunneV- 
it (2.) as in the bell-bind — tmrnpet-ahaptd, 
i in the tobacco flower — rotate or wheel-ahaped^ 
Ilis is flat and without a tube, as in the speed- 
•mhfT'tkcpHi, (5,) or flat, with a tube, as in 
rimrose — tipped or deeply divided into two 

at the limb : this variety may be either 
U or gaping, (6a,) where the two lips stand 
r opeUp u in the white nettle — or pcrtonate, 
when they close op like a mouth, aa in the 
dragon. The corolla is tirap-thaped, (7,) 

daodeliunf tad tultuiar, (8,) in the thistle. 




potjfptlalouM or man) -petallcd coroUx. 
Aimed— 




Cruei/orm, (I,) which have four petals arranged 
in the furm of a croas, aa in all the pUiuts of llie 
fifteenth class, lucb as the wall-flower, stock, 
cabbage, 8cc, Hen the outer part of the petal is 
called the margin, and that part covered by the 
calyx la the elaw — (a, a petal scpuratcd.) 

Papiiicmaceoiu, (2,) when five petals are arranged 
so as to look something like a butterfly, fm Latin, 
papilio,) as in the sweet pea flower. The upper 
petal, which covers over the rest, is called tbc 
veritlum or aiandard, (a,) — the two side petals arc 
alte or wiogs, (&,) — and the two lower and inner 
ones, when joined iagelher, form what goes by the 
name of the carina or keel, (e.) 

A corolla is rosoreAia, (3,) when the petals are 
thin, like those of the rose — and liliaceouit, (4,) 
when tbc petals ore thick, like those of the lily. 




1 X S 4 

The use of the eorolls, spparently, is to defend 
the inner parts of the flower from some injuriea 
they might sustain from wind or damp, and so to 
coUeot and oonoentrmte the sun's light and heat 
upon those parts as to ripen them, and old in the 
more rapid exercise of their functions. 

Necfary. — There Is often found sttaehed to the 
corolla, or situated near it, Tariously shaped and 
colored parts, not contributing to the regular 
formstion of a flower, nor yet apporently necessary 
to its structure. These are the nectaries, parts ao 
called becaose of the honey which some of them 
secteCe— the use of which sweet fluid seems to be, 
that the insects being attracted to the flower, and 
fluttering aboot within it, may aid in distribatiag 
the pollen from tbe stamens to the stigma — a pro* 
cess which is necessary to the well-being of the 
future seed. 

Every flower does not contain a nectary, not eva 
all those which secrete honey, as, for example, tbe 
coroUa tube of the white nettle is sweet, but has no 
particular organ to collect the honey within it. So 
also, many parts are for convenience considered 
nectaries, which fasve no such use. In fsct, every 
part of a flower, which is neither calyx, corolla, 
stamen, nor pointol. Is classed under this general 
term. Tbe nectary, therefore, has the same mesU' 
ing when applied to flowers, as the word fulcrum 
has to the preservstiTe organs. 

fTo he rtmlnwutl.^ 

LIGHT. 

r St'iumed /rvm pcge 143, and cimelutU\i.) 

Corputcuiar Theory qf Light. — Sir John Her- 
schel, in his sdmirable Esiay on Lirjhi in tbe Ency- 
eiopirdia Metropoiitaiui, states the principles of the 
Newtuoisn or corpuscular theory as follows : — 

1, " That ligbt consists of particles of mottcr 
poiiessed of inertia, and endowed with attractive and 
repulsive forces, and projected or emitted from all 
luminous bodies with nearly the same velocity, — 
about 200.000 miles per Moond. 

2. *' That these particles differ from each other 
by the intensity of the attractive and repulsive forces 
which reside in them ; and in thetr relatiooa to the 
material world ; and also in their actual nukiscs, or 
innrtia. 



158 



MAGAZINE OF SCIENCE. 



3. " That Clicse puticlea, impinging on the 
retina, stimulate and exdic vision ; the particles 
whofo inertia ts greatest prodticiitg the sttuBnttoD of 
red, those of the least inertia of riolet, and those in 
which it is intermediate the intermediate colors. 

4. " That the molecules of material bodies and 
those of Light ciert a mataal action on cacl) other, 
which consists in attraction and repalHion, accord- 
ing to some law or function of the distance between 
them ; that this law is auch as to admit, perhaps, of 
several altematioos of cKsoges from repuJaive to at- 
tractive force ; but tbnt when the distance is below 
a certain very small limit it is always attractive ap 
to actual contact, and that bejond this limit residoi 
at least one sphere of repulsion. This repulsive 
force is that which caust's the reflection of light at 
the external surfaces of deaie media ; and the iiite- 
rior attraction tliat wbicli produces tlie refraction 
and interlur reflection of light. 

&. " That these forces have different absolute 
ralnes or intensities, not only for all different ma- 
terial bodies, but for every different species of the 
lominous molecules, being of a nature anolagous to 
chemical sffiuitieA or eJa:tric altroctious ; and that 
hence arises the different refrangibilities of the 
rays of light. 

6. *' That tlie motion of a particle of light, nnder 
the inflnenoe of these forces and its own velocity, 
u related by the same mechanical laws which 
govern the motioiu of ordinary matter ; and that 
therefore each particle describes a trajectory, caps, 
ble of strict calculaliun as soon as the forces which 
act on it are assigned. 

7. "That Che distance between the molecules of 
material bodies is exceediiu(ly imall, in comparison 
nrith the extent of thrtr spheres of attraction and 
repulsion on the particles of light. 

8- " That the forces which produce the reflection 
ud refraction of Light are, nevertheless, absolutely 
insensible at all measureable or appreciable distances 
from the molecules which exert them. 

9. *' Thst every luminous molecule, during the 
whole of its progress through spa?e, is continually 
passing through certain periodically recurring states, 
called by Nrwcon fits of easy reflection and easy 
transmission, in virtnc of which they are more dis- 
posed, when in the former states or phas2B of their 
periods, to obey the inflnence of the repulsive or 
reflective forces of the molecules of the repulsive 
or reflective forces of the molecules of a medium ; 
and when in the latter, of the attractive." 

Soch are the postulates on which the corpuscular 
theory of light depends. Most of them may be ad- 
mitted withont difficulty ; and they afford data for 
the application of malhematical reasoning to the phe- 
nomcna, which may be investigated by the same 
tort of nnalyfiis with which mathematicians are 
already familtar in the theories of heat, capillary at- 
traction, and molecular forces. 

Undulatory Theory. — The principles of the un- 
dulatonr theory ore thus stated by Sir J. Herschel: — 

1. "That on excessively rare, subtle, and elastic 
medium, or e'/Aer, fills all space, snd pervades all 
material bodies, occupying tlie intervals between 
their molecules ; and either by pa»<nng freely among 
them, or by Its extreme rarity, offering no retustance 
to the motion of the earth, the planets, or comets, 
in their orbits, appreciable by the most delicate 
astronomical observations ; and having inertia, bat 
not gravity. 

2. ^* That the molecules of the ether are Buscep* 
tible of being Kt in motioo by the ogitatiua of the 



particles of ponderable matter j and 
one is thus set in motion it oanmunicae 
motion to those adjaccot to it, and thas 
is propagated further and further in all 
according to the same mechanical laws whh! 
late the propogationa of undulations in otUvi 
media, as air, water, or solids, aocordii 
respective constitutions. 

3. "I'hat ID the interior of rcfractinf^i 
ether exists in a state of lets elasticity^] 
with its density, than in vacuo (i. e. in 
of all otlier matter) ; and that the 
the medium, the less, relatively 
elasticity of the ether in its interior. 

4. *' That vibrations communicated 
in free space are propagated through 
dia by means of the ether in their interic 
a velocity corresponding to its iaferiori 
elasticity. 

&. " That when regular vibratory 
{iroper kind are propagated dirough the 
passing through our eyes, reach and 
nerves of our retina, they produce in at { 
tion of light, in a manner beariDg 
close analogy to that in which tlte vibratu 
air afleot our anditory nerves with that of aoi 

G. " That as, in tlie doctrine of sound. 
qnency of the aerial pnlses, or the nnmb< 
sions to and fro Uxyax the point of rest 
molecule of the air, determines the pitc 
so, in the theory of light, the frequency of 1 
or number of impulses made ou uur 
given time by the ethereal moleciilei next 
tact with them, determines the color of ib 
and that as the absolute extent of the motion 
fro of the particles of air detcrmioes the A 
of the sound, so the amplitude or extent ^ 
cursions of the ethereal molecules from 
of rest determines the brightness or int 
light." 

M'hirhever theory we adopt to explain tl 
nomena of light, we are led to conclusions 
strike the mind with astonishment. Accor 
the corpusculsr theory the molecules of lii 
supposed to be endowed with attractive ana 
sive forces, to have poles, to balance thai 
about their centres of gravity, and to 
physical properties which we can 
pond(;rablp. mutter. Inspeaking of I 
it is diflicult to divest one's self of 
ble magnitude, or by nny itrain of tbeimi 
conceive that particles to which they bcU 
so amaxingly small as those of light 
are. If a molecule of light weighed a sii 
its momentum (by reason of the enoi 
with which it moves) would be such, thai 
would be equal to that of a cannon-ball 
projected with a velocity of 1000 feet 
How inconceivably small must they 
when millions of molecules, collected by \t 
mirrors, have never been found to pro^ 
slightest effect on the most delicate appi 
trived expressly for the purpose of rem' 
rauteriality seuslble. 

If the corpuscular theory astonishes 
extreme minuteness and prodigious T( 
lumiuouB molecules, the numerical 
from the nndulatory theory are not leas 
ing- The extreme smalluess of amplit 
vibrations, and the almost inconceiTabl 
measurable rapidity with which Ihoy ii 
other, were computed by Dr. Touog. 



tbB« 

mt ^ 

itenm 



MAGAZINE OF SCIENCE. 



159 



view, it mast Bjipeor singular that 
«, fouuded on uaamptiona so easeo- 
ot, tlioolJ concur in affording themMiw 
gmC ft number of facta with equal 
Oft equal facility. Tbif , boweTer, 
ect to the corpuicolar and udJu. 
ei of light, frotn both of which the 
lawa to which the phcoomeaa are 
be deduced, though not in all cases with 
ree of facility. So fur as the corpua- 
atailable for the purposes of de- 
on. it poftse^aes all the charac- 
d theory. It luppoaca the opera- 
vith which we are in some meaanre 
fWe are accastomed to contemplate the 
traction in the grand phcDonieDa of aa- 
«e perceive them at every Instunt in the 
tendency of all heavy bodies ; and though 
in the small bodies of natnre, tbej 
d in the phenomena of electricity, 
capillary attraction, electricity, and 
ical aetiooi, where they can be not 
ty traced, but reduced to mathematical 
d submitted to accurate calculation.— 
torr hypothesis is not seized by the 
the same facility; yet it also possesses 
least equivocal characteristics of philO' 
Ch. No phenomenon has yet been dis- 
,y at variance with any of its prin- 
contrary, most of the phenomena 
principles with remarkable ease ; 
pMrous irutaocea, consequences deduced 
theory by a long and intricate analysis* 
ao sagacity could possibly hare tiiviQed 
have been found to be aaturately true 
t to the test of experiment. Hence 
begins to be generally adopted by 
and. in recent times, by far the most 
lumei in the annals of optical discovery 
in the list of its supporters, 
sensation of light is produced by the 
4rf an ulxemely rare and subtle fluid, is 
|l was maintained by Descartes, Hooke, 
but it is to Huyghens that the 
of having reduced the hypo- 
shape, and rendered it available 
mechanical explanation. Owing 
of Newton in applying the cor- 
to his splendid discoveries, the 
Haygbens were long neglected ; in- 
theory remained in the same state in 
left by him till it was taken up by our 
the late Dr. Voung. Ky a train of 
I reasoning, which, in point of ingenuity, 
been equalled. Dr. Voung was con- 
very remarkable numerical relations 
e oi the spparently most dissimilar phe- 
Optici, to the general laws of diffraction, 
trae principles of the coloration of crys- 
ces. Malus, so late as ISIO, made 
bant di!ieovery of the polnritation of light 
CM), and succeflsfully cxplainird the phe- 
i^ the hypothesis of an undulatory pro- 
The theory nub-tequently received a great 
from the ingenious labors of Kresnel ; and 
ore recent resr-*rches of Arago, Poisson, 
Airy, and others, have conferred on it so 
Urae of probability that it may be almost 
I ranking in the doM of demonstrated 
Ic Is a theory." says Ilerfchel, ** which, 
ikled in nature, is certainly one of the 
Kmmm that the gcntua of man has yet 




invented to group together natnral phenomena, as 
well as the most fortunate in the support it has re- 
ceived from whole classes of new phenomena, which 
at their discovery seemed tn irrccoocileable opposi- 
tion to it. It is, in fact, in all its applications and 
details, one succession o( /eticitie§ : insomuch that 
we may almost be iadaced to say, if it be not true, 
it deserves to be so." 

Helationa of Light and Heaf. — Light and heat 
are so intimately related to each other, that philo- 
sophers have doubted whether they are identical 
principles, or merely coexistent in tbe luminous 
rays. They poHSess numerous pro[>erties in com- 
mon ; being redected, refracted, end polarized ac- 
cording to the same optical laws, and even exhibit 
tbe same phenomena of interference. Most sub- 
stances, during combustion, give out both light and 
beat ; and all bwUea, excepting the gases, when 
heated to a high temperature become incandesc4>nt. 
Nevertheless, there arc many circumsUncea in which 
they appear to difier. 

A thin plate of transparent glass interposed be- 
tween tbe face and a blazing fire intercepts no sen- 
sible portion of the light, but most sensibly dimin- 
ishes the heat. Light and heat ore, therefore, not 
intercepted alike by the same substances. Heat is 
also combined in different degrees with the different 
rays of the solar spectrum. A very reniarktble 
discovery on this subject was made by Sir William 
Herschel, which would aecm to establish the Inde- 
pendents of the beating and illuminating effects of 
the solar rays. Having placed thermometers in 
the several prismatic colors of the solar spectnun, 
he found the heating power of the rays gradually in- 
cr^cd from the violet (where it was least) to the 
eimme red, and that the maximum temperature 
existed at some distance beyond the red, out of the 
visible part of the spectrum. The experiment was 
soon after repeated with groat care by Berard, who 
con6rmed Herscbers conclusions relatively to the 
augmentation of the calorific power from the violet 
to the red ; but he found the maximum heat ex- 
isted at the extremity of the red, and not beyond 
the spectrum. This discovery of tbe inequality of 
the heating power of the different rays led to the 
inqairy whether the chemical action, produced by 
light on certain bodies, was merely the effect of the 
heat accompanying it, or owing to some other cause. 
By a series of delicate experiments, Bemrd found 
that this action is not only independent of the heat- 
ing power, but follows an entirely different law ; iCa 
intensity being greatest in the violet ray, where the 
heating power is the least, aod least in the red ray, 
where the heating power is greatest. We arc thus 
led to the conclusion that the solar rays puasess at 
least three distinct powers, — those of heating, illu- 
minating, and effecting chemical combinations and 
decompositions; and these powers are dislribated 
among the differently refrangtbh; rays in such a 
manimr as to show their complete independence of 
each other. 

Light acts a very important part in the vegetable 
economy. The green color of plants and the hue 
of flowers entirely depend on it ; and il is found 
even to influence the form of their leavps. lu ef- 
fects in developing the forms of wome of the lower 
claises of animals hare also been proved by various 
experiments ; and there are probably many other 
powers resident in the same wonderful agent of which 
we can at present form no adequate notion. 



9 



160 



MAGAZINE OF SCIENCE, 



MEMORANDA. 
FitrmatioH 'tf RockM. — Though seveni] of tbe 
agencies which operated during the carliett eru in 
the phycicol hiitory of oar i^lobe either now exert a 
comjiaratiTely diminished iu0uence, or have ceased 
altogether, yet the general Uw of nature unquestion- 
ablf continues the same, and rocks ore in course of 
formation by various causes, and under dlTeraified 
circunutanceB, at the present daj. Not onlj do 
tbe coral formadoas continue in the southern ocean 
to produce rcefi, ialands, and by the connexion and 
jncrease of thes«, to form coDtlnents ; but, in our 
own Islands, accumulations of sand, mud, and shells, 
are producing fresh layers in tlic bed of the sea, 
and constituting fr(»h deposits, which add to the 
cnut of our globe, and will form a subject of in- 
terest to the future inquirer into its history ; but 
every river and every stream is in like manner con- 
verting ita bed into rock, and the operation is often 
assisted by causes of an extraordinary and singular 
kind. A very remarkable instance of this nature 
was brought to light a few years since. Daring the 
unhappy and distracted reign of Edward II. several 
of the English barons took up arms against the 
monarch and his favorites, tbe Gavestooes. One 
of their insurrections was headed by the Earl of 
Leicester, whose associate in the enterprise was the 
Earl of Lancaster, tbe litter nobleman taking charge 
of the military t^est, and the paying the troops, 
&c. &c. While the insurgent army were crosalng 
the river Dooe, in Derbyshire, in the night, they 
were attacked and routed by the king's troops ; — 
and, in the confusion, the military chest, with its 
contents, was thrown Itito the stream, and sunk to 
the bottom. The Earl of Lancaster was ah^y 
after beheaded (iu March, 1322). and all trace of 
the tre:asure was lost light of. After the lapse of 
half a thousand years, on some ezcavaiions being 
made a few years since for the purpose of deepen- 
ing tlie bed of the river, masses of ferruginous brco- 
da— that is, of pebbles, gravel, &c., cemented into 
rock by tltc mst of iron, were found, many of them 
containing coins of tlie period, silver pennies of 
Edward L, \c., evidently funning portions of the 
lost treasure. It would socm that the box contain* 
ing tbe money bad been bound or otherwise fitted 
with iron, and that the decomposition uf the metal 
had produced a cement aufficient to convert these 
pebbles into rock. The circumstance is not alto- 
gether unique ; and the efficiency of iron to pro- 
daoe Bneh a result ia perfectly weU known ; but the 
prescrration of these cotus by so remarkable a rauise 
constitutes a highly remarkable and interesting fact. 
Bhiith Queen. 

AVic ftrtife qf Iron. — This combination has been 
obtained by M. Fremy. It commnniciitea a violet 
color to water, and possesses a powerful dyeing 
principle. It resembles manganese diamcleon. It 
decomposes readily when boiled with an alkali or 
organic subst.tnce having an aifioity fur oxygen, 
and is converted into oxygen and scsqni-oxide of 
iron, of a yellow color. This combination is a pcr- 
ferrnte of potash, which may be procured by calcin- 
ing peroxide of potassium and peroxide of iron. — 
Fremy has shown that tbe appearance of a chame- 
leon color ia no proof of the presence of man^ncsc, 
as it maybe confounded with the new oxide of iron. 
Fremy forms this oxide by igniting a mixture of 
potash and peroxide of iron ; a brown mass ia the 
result, which, by digestion in water, gives a beau- 



tiful violet'rrd solution. This compound is very 
soluble in water. A large quantity of water dccoro* 
pose* it In the couneof time. It beeoraea insolabk 
in very alkaline water, farming a brown premnitate, 
which readily dissolves in pure water, and alorde ■ 
fine purple solution. It appears much leas stahlc 
than manganate of potaah. A temperature of 111^ 
decomposes it immediately ; all organic substaacw 
decompose it. It is consequently impossible hi 
filter the solution. It is impossible to isolata tUa 
compound, for when the red solution is treated bf 
an acid, when the potash is saturated, ozygm U 
disengaged, and peroxide of iron predpttated. I( 
the acid is In excess, it dissolves ue peroxide, and 
gives rise to the formation of peroxide salt of inm. 
GUug Church'BelU are among modera «oodfln» 
One has just been cast in Sweden ; iti '"■'■*i*it fa 
six feet, and its tone is said to be finer than soy 
metal bell. — Tyne Mercury. 

U»e of Lime in Planting TYftt. — A large planta- 
tion has, within the last two or three years, bean 
formed in the neighbourhood of InTemess, without 
the loss of a single tree, and this has been achieved 
by a very simple process. It is merely putting a 
small quantity of lime in the hole with the plant ; 
about four bushels of lime will suffice for an acrtL 
It must be thoroughly mixed and incorporated with 
the mould before the plant is inserted. The 
of the lime Is, to push on the growth of the 
in its first and most precarious stage. New 
begin to form and ramify from the top root | 
not only is the safety of the plant ensured, b«t 
growth is advanced in double ratio. — /i 
Courier. 

Kalorama. — Under this title an exhibitioB of • 
novel kind has been thrown open in Bond StrefC 
It consists of Isndscapea on a large scale, and pKw 
senting trees, water, animals, human figures, 
every variety of scenery ; but instead of cauvai 
color, being composed of paper cut out with 
and by disposition and gumming together, m 
represent all these features in a very effective 
nrr. In some points the distances are 
having the materials on different horixontal 
in others, by painting tbe baekground. As obj 
curiosity, these Kaloramic products deeerre a 
Muiie uf Liffht. — Dr. Buchanan, of Ken 
conceives that he haa found some affinity 
the different rays of light, as presented iu a 
bow, and the Dot«8 of music. Following up 
theory, real or imaginary, be proposes to 
concert for the eye ; that is, that tfie eye 
experience the same pleasure by an harmonic 
and fall of the different rays of tight, as the 
does by the accordance of sweet sounds. How 
this plan is practicable, ia a thing resting on exj 
mpnt. Something analogous to this may have 
birth to the fable of Memnoo's harp, which 
said to havr uttered delightful strmixis of 
when touched by the solar rays. 

Th Demlruy Caterpillarf, — A mode of d 
caterpillars has been discovered by accidcnL 
piece of woollen rag had been blown by the 
into a currant-bush, and when taken out was : 
covered by these leaf-devouring insects. VUtm 
wooUen cloth were immediately placed on 
hush in the garden, and next day the cai 
had universally taken to them for shelter, in 
way thousands were destroyed every motningi 
National Advertiser. 



LVKOON. 



-Pruned hy U. I nA^cti. 6. Whlu- Jlurw Une. Mil* End.— Poblifibe*) by W. UmTUtix. H . PatCisoitcr KtfW. 
Eaiaburuli, J Msksiss.— OJugow. O. Daici and J. DAaim.'^UvcrjiwI. J. Fsmr. 



16*2 



MAGAZINE OF SCIENCE. 



BATE'S POLYANGULAa KALEIDOSCOPE. 

Itf the common kalctdoscopcA, the reflecting planes 
are Axed in an invariable an; le, whiL'U la aotuti even 
aliquot part of 360"^ ; and, therefore, though the 
forms or patterns which they create are literally in- 
finite in number, jet thej have all the oanie chft' 
racter, in so far as they are compotcil of as many 
palrf of direct and inverted images as half the num- 
bcr of times that the inclination of the rcflecton is 
contained in 360'^. 

U is of the greatest importance, in the ■ppUra- 
tion of the kaleidoscope to the arts, to have it con- 
structed in such a manner, that pnttema composed 
of any number uf [laira of direct and inverted images 
may l>c created and drawn. With this view, the 
instnintent may be fitted np in various ways, with 
paper, eliith, and metallir joints, by means of which 
the angle ran be varied at pleasure j but the must 
convenient metliod is shown in the polyangular ka- 
leidoscope, the construction of which is as follows : — 

The three figure*, viz. I, 2, 3, represent the 
polyangular kaIeido»cnpe «*ith mftoUic reflectors, 
■1 made by Mr. Bau. optician. Rg. 1 shows the 
complete instrument, when mounted upon » Htand ; 
fig. 2 is a section of it in the direction of it» Irn^th ; 
and fig. 3 is a transverse section of it througb the 
line ST, fig. 2. The tube of this instrument is 
compofted of two cones, MM, NN, fig. 2, con- 
nected together by a middle piece or ring R R, into 
which Ihey are both screwed. These two cones 
inclose two highly-polished metallic reflectors A O, 
BO, fig, 3, only one of them, viz. IH) E. being 
seen in fig. 2, One of these reflectors UOE. is 
fixed to tbe ring R R, by the intermediate piece 
K G L. The reflector is screwed lo this piece by 
the adjustable screws K L ; and the piece K G L is 
again fixed to the ring RK by two screws seen 
atwve and below G, in tig. 3. Hence the tube, 
cortmistiiig of the cones MM, N N, and the ring 
R R, are tnimoveably connected with the mirror 
B O K. The surface' of the reltector B (> E is ad- 
justed by the screws at K and L. till it passes ac- 
curately through t)ie axis of the cooes and ring as 
seen in fig. 3. The oiher reflector A O, is fixed 
to an outer ring X X, by means of an intermediate 
piece, similar to K G L, the srm P of which, cor- 
respondinj^' to G, pluses tKroush on onnulor space. 
or open arch, of more than 1(0', cut out uf the clr- 
runifcreuce of the inner ring R R, Tlie arm F is 
fixed to the outer ring X X by two screws, seen 
above and below F, iu fig. 3 ; and the reficctor 
A O is filed to the bar corresponding to K L, by 
simitar screws, for the purpose of adjusting it. 

The lower edge O E of tbe reflector B O E ex- 
tends about the ISlh of an inch below the axis of 
the coues, as represented by the dotted line in fig. 
'2 ; but the lower cUrc O E of the other reflector 
A O E, which is finely ground to an acute angle, 
forming a perfectly straight and smooth line, is 
placed exactly in the axis of tlie cones, so as just 
to touch a line in the reflector A O E. which ootn- 
eides with the Btia of the eones, and to form a 
juction with that line in every part of the two mret- 
ing planes. Tbe very nice adjustments which are 
necessary lo produce so exact a motion are etfcctcd 
by the screws corresponding to K and L. 

If wc now fix the outer ring X X into the ring of 
« stand ST, so as to be held fast, and turn the 
cones with the hand, we sball give motion to the 
reflector BO, so nj to place it at anv angle we 
please, from O"* to 90'^; and, during 'its motion 



through thb arch, the junction of the two rrflrctort 
must remiUn perfect, if the tootbiiii; lines are ad* 
justed, as we have described theni. to the asi* of 
motion, which must alao be the axis of th« nwa 
and ringa. If. on the conlrarr, we take away die 
stand, and, holding the instrument to the hand ky 
either of the eones M, N, turn the ring R with thi 
other, we shall ^ive motion to it# reflector A O, aad 
produce a variation in the angle in tbe same man* 
ner as before ; or the same effect may be produoed 
by an endless screw working in Ceeth, cat upon Che 
circumference of the outer ring X X, 

In order lo enable the observer to lost the rt- 
flectora at once to any even alit|UOt part of a rirde, 
Of so as to give any number of pairs of direct and 
inverted iraagrs. the most convenient uf the e^ett 
aliquot parts of the circle ore engraven uj»on t^r 
ring X X ; so that we have only to »et the tndn lo 
any of these parts, to No. 12 for example, end tte 
reflectors will then bo placed at an angle of 3<r, aatf 
will furm a circular field with ttreire Inminoua see- 
tors, or a star with Hx points, and, consequently, a 
jiaitem composed of tix pairs of direct and inTtrtari 
images. 

As the length of the plates is only aboat Alv 
inchrs, it is necessary, excepting for persona ytn 
short-sighted, to have a convex lens placed at 1L 
A brass ring, containing a plane glass, screws Ial9 
the outer ring C D, when the instrument la aotiv 
use ; and there is on object plate contaimng Iraf- 
menU of difTerently colored glau. This object 
plfltc consists of two plates of glau, one gnraiail» 
and the other trauiparent, set in brass rims. IW 
transparent one goes nearest the reflector, and the 
brass rim which contains it screws iuto the other, 
so ss to inclose Iwtween them tbe colored fn{- 
ments. and re^^lar figures of colored and twisted 
glass. A loose ring surrounds this object pUte ;— 
and when this ring is screwed into the circular rfai 
C D. the object plate can be turned round vj *^ t/> 
produce a variety of patterns, without any risk of 
its being drtacbed from tlie outer oone. 

In applying this instrument to opaque objetfts. 
such as engravings, coins, gems, or fragments of 
colored gloss laid upon a mirror, tbe aperture of Ibt 
mirrors is laid directly over them, the large cone ^ 
M M having been previoujily unscrewed, for the 
purpose of allowing the light to full fnrly upi>u the 
objects. Tilts property of the kaleiiloscope is of 
great importance, as in every olber form of tbe In- 
strument, opaque objects mukt be held obliquely, 
and, therefore, at such a distance from the rrflectun 
as must affect the symmetry of tbe pattern. 

As the perfection of the figures depends on tliJ . 
reflectors being kept completely free of dust, parti- 
cularly at the angles, where it naturally accumulatM. 
the greatest facility is given by the preceding con* 
sCmetion in keeping them clean. For this purpoo?, 
the large cone must be unscrewed ; the reflcctAfi 
having been previously closed, by turning the ind« 
to 00 on the ring. They are next to be opened tt 
the utmost, and the dost may in general be removed 
by means of a fine point wrapped in clewi and dry 
wash leather. If any dust, however, alill odherVt 
the small screw in the side of the rini; oppoiltt la 
the index should be removed, and the snc'iT i .'iic. 
K N, olso unscrewed. By casing the ■ 
screws of either of the reflector*, thru 
sides will separate, so as to allow a piece i»r ili; «»ii» 
lenther to be drawn between them. When crwy 
ptrlicle of dust has been thus removed, the metih ' 
should be re-adjusted and dosed before tbe conei 



MAGAZINE OF SCIENCE. 



\G3 



rrpltcrd ; both of which should he icrewed 
■ < Uic ring K R. 

<\i« of m>ition in the prrc^din; conftruc- 
'sjurily the axis of the cones and ring*, 
'■r of l)ir*e coiK'fl and riiif^a must everj 
double the breadth of the retlpctor*. — 
frnn thU caiue, the tube, and con«eqaentl; the 
pbjttf pUU>t arr widr, and the inaCmmcut is, to a 
r«rtain dufree, nopartable. 

Tijtf sdvuitogea which th« polyangular kaleido- 
>pM poaaesa over all uthers, are— 
1. Tbat pattema of an; Dumber of eectort, from 
|}ii> HimnU^t to tho most Complicated, can be ca&iljr 

>'- the reflector! can be let, with the moit 

rrf«ct M'ruraey, to an even aliquot part of a rirclc. 

i. That the rcflectari can be, at any time, com- 

' 4nrd and freed from all the diiitt that ac- 

bctv^eo them, and the instrument ren- 

v.. ~. jKxfacC aa when it cane from the Jundi of 

m»ker. 



(SIECTS AND THEIR CLASSIFICATION. 

CT4 Are animuU which have a bodj coRM«tin)( 
w or more divisions, articulated feet, and a 
,k«a ■-■^"-picnoualy distinct from the boiW, un whiuh 
1 two moveable horns, called anlennK. 
.the through airholes, which are situated 
liic atdcfl of the body; the greater number have 
wi]r» in iheir perfect state, and only a propurtion- 
"1 number are entirely without them. With 
ion of certain groopa, all perfect inspcta 
(i9»T Bii (Vet, and their bodiea are divided into a 
bead, thorax, und abdomen, by notches or incisions; 
brncr the name iiufct, derived from the I^tin word 
«*fC«re, to cut or notch. Before they attain their 
perfect »tate they arc subject to variooa transforma- 
ttuna, whic}i are called metamor})huses. For the 
lake of penpicoity tlie very numerous class of in- 
■ct«, the tnoit extensive in the whole animal king- 
dom, faai been dtvirlcd into two principal dtviaiuni 
- fh,- aini^, and the winglesa. 

■I ifutctt ure divided into the following 

tl.J CoMptFva (Boetlw; Sheath- wings). Six 
^, and mostly four wings, Uie anterior pair of 
*hieh arc homy* in the form of a covering for the 
t»o pokterior wings, which are sometimes wanting. 
Utey haxe tijipcr and lower jaws (uianilibK's and 
•uaillc) for giiAwing or chewing : their under wiugs 
vt trwisTcrfely folded. Exanipin — the may-bug, 
the long-horna (Ccnimbycidie), atag-bcetles. ground- 
lioclles iCarabidse), weevils, &c. 

(2.) Orth6pUra (Straight-wings.) Six feet ; four 
•ingi, the two anterior of a leatliery aub&tance, 
tarring as covcm to the pusterior, which are folded 
ioCh loDgitodintliy nod tmnsrersely, but m^rc gene- 
n^ only loDgiludinally (whence the name straight- 
■Ifligvj, aud which lie, when at rest, couccaltd un- 
der Ihe others. They have upper and luwj-r jaws 
(or Bandibles and ooaiilla:) fur chewing. Examples' 
—^kif f^^rwig, the black-b<wtlr, the cock>roach, the 
^et, the migratory locust, and llic green 

^....( iiruapifra (Half-wings). Six feet; four 

viofS, the two anterior forming hard coverings with 

lartnbrauotu ends, or recembliog the lower ones, 

Larger and stronger. Instead of upper 

j4Ws, the organs of the mouth are furnii'd 

• incloacd in an ortirulal^-d klicath, nf u 

J oc oooicdl ahitpe, jnd funning u ]iil>;cc1- 



in% beak or nieker. Examples— the field and tree 
bugs, house bags, cicada;, and aphides. 

(4.) ftitur6ptffra (Net-wing*). Six feet; four 
meuhrnnons naked wings, upper and lower jaws 
for chewing ; the wings are delicately veined, the 
under nearly the sise of the upper, or even broader 
in diameter. Examples — the dragon-fly, or Libi'I- 
lu)n; lace-fly, or Hemerobioa -, and day-fly, or 
Ephticnera. 

(j.) f/jrmeH6piera (Membrane- wings). Six feet; 
four membranous wings, upper and lower jaws ;— 
the posterior wings smiiUer than the upper. In tlie 
abdomen of the female of most species is n sting, or 
ovipositor. Example! — the aaw-flwa (Tcntbredt- 
nidai), Sirex gigai, gall-fly, bcea, wasps, humble- 
beea, and anta. 

(G.) Lepidoptera (Scale-wingi). Six feet ; fbnr 
memhrannna wings, covered with small, rolorcd, 
mealy, shining scales or feathers. Instead of the 
upper and lower jaws, two hollow ftlamenla exist, 
which tOj;ethcr form a spirally rolled tongue. Ex- 
amplea — butlerfliei, moths, and bawk-moLlis. 

(7.) Rhipipiera (Fan-wings). Six feet ; two 
membrantnta wings, folded like a fan; oa the an- 
tertur part of a thurax are situated two fmall, bent, 
hard, moveable bodies, like wing-covers. Tha 
mnFticatory organs consist of simple briatle-shaped 
mandihles, and two palpi. To this order belong 
two gcuern of parasites living on wasps and heea. 

(_H.) jyiptera (Two-wiogs). Six feet ; two mem- 
branous expanded wings, generally with two more- 
able organs, called poisers or balancera, and which 
are situated behind the wings. The organs of the 
mouth consist of a sucker, formed of a variable 
number of bristles, which are inclust-d in an un- 
nrticulated sheath ; terminated in a double lip. 
Examples — gnats, midgei. house-flies, ox and horae 
breexe-Hiea, \c, 

Jnatct* wUhout winffs consist of the following 
orders: — 

(9.) MyridpoJa (ThouMnd-fert. Millepedes). — 
They have more than six feet, twenty-four at least, 
□ nd upwardn, whir.li arc plnrrrl on a series of rings, 
extending the whole length uf the body ; each ring 
has gt-ncrally two pairs. The ftr»t, and sometimea, 
also, the second pair, form parta of the month. 
Examples — the centipede, iulua, and scolopendra, 

(10.) Thymnitra (I'ringe-UiU;. Six feet; on 
the under aides of the abdomen are situuted flat 
niovenble appendages like pro-legs, and at the ex- 
treuiity is a forked apparatus, by which the body 
can raise itself and move by leap:*. Example — the 
sugar-louse (Lrpisma sacchnrinam). 

;ll.) Para»tfa (Varasites). .Six feet j no other 
organs of sight except aimple (instead of composite) 
eyes ; the mouth is mostly internal, and conaltta of 
a snout, which contains a retractile sucker, or it 
forms a clrft with two lips, two mandthici, and 
hooka. Examples — the ditfcrcnt spccie-» of lice. 

(12.) Sncturia (Suckers). Six feet, of which 
the posterior are the longest, and adapted far jump- 
ing. These undergo a transformatiou, and actptirc 
organa of motion which they had not at first. The 
mouth conaittts of a sucker, which )& inclosed in n 
cylindrical aheath, and is formed uf two articulated 
piecea. Example — the flea. 

CVflA* and npidct'i, which Linnreui included 
among insects without wings, arc now formed into 
two distinct claaiMts — CruBtacea and Arachoida. 

The arranij/fmrftf Mere tjhmt i* thnt of KollNr; — 
but other nulhorsdilft'-T in thfir \iKWftof the aubjed. 
Uy some the earwig is formed into au order distinct 



MAGAZINE OF SCIENCE. 



Irom the Ortb(jpterft. The Tbrfpi ii leparated u 
an order from the Hemfptrra, the CAddice*fli«« 
(Phryg^eA) rrom the Neuruplera and the horse- 
flies (Hippobosca) firom the Diptera. la a popular 
point of view the arran^ment of KoUar may be 
cODiidered ai lufficiently detailed. 



ANIMAL MAGNETIS.M. 

Tbis Bobject haa lately attracted so mnch of pnbUc 
attention, that we ibould not be joBtifted in wholly 
omitting an account of it, more eBpetrislly as it 
pretenda to be intimately connected with subjecta 
which we have found occasion to treat of ratber 
fully. Before, howeTCr, we allude to the present 
operations of the cbarlattms or eothuaissts, wbieh 
ever tbey may be, who now impose upon the cre- 
dulity of the public, it will, we doubt oot, be inte- 
resting to present to our readers tlie authenticated 
proceedings of the original magnetiser, M. Metmer, 
with the fundamental principles upon which the 
pretended idence was originally contrived. 

On the 12th of March, 1781, Louis XVf. sp- 
pointed Messrs. Borre, LalUu, Darcet, andGaillotin, 
members of the faculty of Paris, to examine tbe 
animal magnetism, practised by M. Oeslon and 
Meamer, and to give in a report to him on tbe sub- 
ject ; and in conscqncnce of a request made by 
these physicians, His Majesty appointed live mem- 
bers of the Academy of Sciences, Messrs. Franklin, 
Leroi, Bailly, De Bory, and Lavoisier, to scsist them 
In this exaniinatioD. As M. Bory died when tlie 
commissioners began their labors, His Majesty made 
choice of M. Msjanlt, member of the faculty of 
medicine, to succeed him. The following is an 
eitract from their report : — 

" Doctrine. — Tbe agent which M. Meamer pre- 
tends to have discovered, and which be has made 
known under the name of animal magnetism, is a 
fluid diffused throughont the whole universe. It is 
the means of a mutual ioflnence between the celes- 
tial bodiea, the earth and animated bdngs. It is 
continued in such a manner as to leave no vacuum -. 
its subtlety is beyond all comparison ; it is capable 
of receiving, propagating, and communicating nJl 
the impreasioDi of motion, and is susceptible of a 
flux and reflui. Animal bodies experience the effects 
of this agent, and it Is by insinuating itself into the 
tabatonce of the nerves, that it immediately atTects 
them. The human body, io particular, possesses 

Eropcrties analogous to those of the magnet, and it 
as alio its dllTeretit and opposite poles. 
** The action and virtue of animal magnetism may 
be communicated from one body to other bodies, 
either animate and inanimate, and even at a con- 
aiderable distance, withont the aid of any interme- 
diate body. It is increased and reflected by glass ; 
it is commnnicaled and propagated by sound— io a 
word, this virtue maybe occumnlated, concentrated, 
and transmitted. Though the fluid be universal, all 
animated bodies are not equally susceptible of it ; 
there are some even, though few in number, of a 
nature so hostile to it, that their presence alono 
destroys all the effects of it in other bodies. Ani- 
mal magnetism can cure immediately all diseases of 
the nerves, and others it cores mediately ; it 
Btrengtheni the action of medicines, and it cxrrts 
and directs salutary ones in such a manner that 
they may be overcome. By its means the phy- 
sician can ascertain each individual's state of health ; 
and can speak with cert^nty respecting the origin, 
nature, and progress of the mo»t complicated 



diseasea. He can prevent their increase, and be 
able to cure them without ever expostng the paciot 
to dangeroiu effects, or disagreeable oonaequeaesa^ 
whatever be tbe age, the temperature, or the •«. 
In animal magnetism, natare preaents an vuvrnsj 
medium for curing and preserving mankind. Suh 
is the agent which the commiauonera were charged 
to examine, and anch tbe properties warranted by 
M. Deslon. This physician, when he explained to 
the commissioners the doctrine and nature of aiiiiiwl 
magnetism, taught them also the practice, and 
made them acquainted with the poles, by ihowlttg 
them the method of touching the patients, and of 
conveying to them the magnetic fluid. 

" Treatment, — Af^r having procured informidoD 
respecting tbe theory and practin: of animal mag- 
netism, it was necessary to see its effects. For this 
purpose the commissioners attended, and each of 
them several times, to observe tbe manner in which 
M. Deslon treated hia patients. In the middle of 
a large hall, tbey saw a circular box, made of oak, 
rsiscd to the height of a foot, or a foot and a half* 
which was called tbe tub ; tbe upper part of tiris 
box was pierced with a great number of holes, bom 
which proceeded iron branches, ba\'ing moreihle 
elbows. The patients were placed in rows aronad 
this tub, each opposite to one of the iron brancbesi, 
which by means of the elbow could be applied di- 
rectly to tbe diseased part. They were all united to 
each other by a rope that went round their hoSa ; 
and sometimes tbey formed a second chain by layii^ 
bold of each other's bands— -that ia to asy, by each 
applying the thnmb between the thumb sod fore- 
finger of the next person. In a comer of tbe baD 
stood a piano-forte, on which various aire were pl^ycA 
in different time ; and these airs were sometimas 
accompanied with tbe voice and singing. All the 
magnetised persons held in one of their hands la 
iron rod, about 10 or 12 Inches in length. TU« 
was called a niftatlie tractor, M. Dealoa declared 
to the commissioners — First, that thia rod was t^ 
conductor of magnetism ; that it posseased the pro- 
perty of concentrating it at its pofait, and of ren- 
dering its emanations more powerful. Second, Ibat 
sound, according to the principles of Meamer, wM 
also a conductor of magnetism, and to commanlaMi 
tbo fluid to the piano-forte, notliing waa DeeoMVy 
but to bring the iron rod near it ; those who tooctwa 
the instrument furnished It also, and tbe mognetiaB 
was transmitted by the sounds to tbe s 
patients. Third, the rope which went 
patients, as well as the joining of bands, 
ttned to increase tbe effects by commnnicatiM. 
Fourth, the inside of tbe tub was couatructed in 
SDch a manner, aa to concentrate the magnetism. 
It wns a large reservoir, from which it was propa- 
gated by meaas of tbe iron branches Axed in it. 

" The patients arranged in great numbers, and iB 
several rows, around the tub. received the magnet' 
Ism at the same time by all these means— by the 
iron branches which transmitted to them the 
msjenetism in the tub — by tbe rope twisted wanS 
their bodies — by tlie joining of hands, which com- 
municated to those of their neighbours ; and by 
tbe sound of the piano-forte ; or of an sgreeable 
voice. The patients were magnetised also 
by means of tbe finger, and of an iron rod 
before tbe face, or behind the head, and on 
eased parts, always observing the distioctioa of thi 
poles : the person who performed the operatiM 
acted upon them also by }be look, and by 
at them ; but they were magnetised in ■ 



^M 



MAGAZINE OF SCIENCE. 



165 



bj* Applying the fingers to the hypochon- 
druc regions, and aometlmefl coDtuiumg to du to 
tat MTfral hoars. 

" J5E^«t/*. — The paticmts exhibited a highly-varied 
yieUuv, ttccording to their different ftatea. Some 
flf them were calm and tranquil, and experienced 
BO «flect whatever ; other* cou|^hed, spat, and felt 
MBA tUght pain, a local or a universail beat, and 
titM of penpiration ; others were agitated and tor- 
mented nith conruliionf, which were remarkable 
§or their number, their duration, and Tiolcnoc. Aa 
•DOB *a one conrulsion begaSt aereral others inani- 
tatad tbemselres. The commijAoners saw some 
«faidh lasted three hours ; tbey were accompanied 
'Vidi the expectoration of a turbid, viscous liquor, 
loreed ap by the violence of the efforts. Sometimes 
atreaka of blood eamo np ; and one young wan in 
ptfticvUr, one of the patients, tlirew np a great 
deal of it. These convulsions were characterised 
Vf sudden and involuntary movements of all the 
Kmbs, or contraction of the throat, snbsultus of the 
kfpocbondrta and the epigastrton, uneasiness, a 
vUfaen of look, piercing cries, weeping, hiccups, 
■id bDmoderate laughter; they were preceded and 
Ulomd by a state of Inngoar, and often a sort 
of d^ection and even lethargy. The least unex- 
Doise produced in the patients a tremour ; 
it was observed that changing the tone and 
of the oin played on a piano-forte had an 
iftflaence oq them, so that by lirelier tonea they 
vere more agitated, and the vivacity of their coo* 
mlsions was renewed. 

*'A hall, lined with matUng, had been at first 
dcptined for patients afflicted with these convulsions. 
aad on that account waa called the chamber of 
criea ; but M. Deslon does not think proper to 
saake use of it, and all the patients, whatever bo 
their symptoms, are collected together in the public 
han. 

** Nothing can be more astonishing than the ap- 
Maraoc-e exhibited by these convulsions ; none but 
nOM who have seen them can form any ideji of 
then : and those who sec tfaem are not a little sur- 
prised at the prnfound tranquility of one part of the 
patients, and the agitation experienced by another; 
Umt varioos symptoms which are rep'tated, and the 
■ympathetie emotioos produced. Some patients 
themselves to each other exclusively, rush 
each other, langh, address each other in an 
tone, and mutaally poften each other's 
Tbey are all subject to him who magnetises ; 
ftcmgh III an apparent state of stupor, the sound of 
Us Toic«, a look or a stgn, is sufficient to rouse 
tkem from it ; and in consequence of these constant 
It is impossible not to acknowledge some 
power by which the patients are agitated and 
tobdned, and of which he who magnetises seems to 
he the depository. 

*' Qmc/iuion. — The commiastODers hnving asccr- 
taJDad that this animal>mag:netie fluid c&nnot be 
fSvelTcd by any of our senses ; that it has no 
Mlion either on them, or on the patients subjected 
to U ; and liaving assured themselves that pressure 
Md lOMching occasion changes seldom favorable in 
ttSBiiDsl economy ; and in the last place, baring 
dBDOMftiBted by decisive experiments, that the 
faHfiAaUuD, without magnetism, produces con- 
walnoas, and that magnedsm, withoat the imagt- 
Mfion, produces nothing, have unanimously con- 
riadtfd. in regard to the question of the existence 
and utility of the magnetic fluid, that nothing 
protvs its existence; that the violent effects oh* 



BCrved on those subjected to public treatment, arise 
from touching ; from the imagtnaUuD being put in 
action ; and from that mechanical imitation which 
impals OS, in spite of ourselves, to repeat whatever 
strikes our senses. At the same time, ihey think 
themselves obliged to add, as an observation of im- 
portance, that frequent touching, in*^ the repeated 
action of the imagination to produce a crisis, may 
be prejudicial ; that the sight of these crises is 
equally dangerous, on account of that imagination 
which nature seems to have imposed on us as a law, 
and consequently that all the public treatment, 
where thetaeons of mugneUsm ore employed, most 
in the end produce disastrous effects.** 

i'nru, March Hlk. I7fr4. 

MUSICAL STRINGS. 

If a string be stretched between two pins, and then 
be struck or pulled to one side, it will move as far 
to the other side, and then nearly as for back again, 
and that vibrate for a considerable time ; — each vi- 
bration diminishing till they finally cease — though 
the time occupied in each vibration, from beginning 
to end, is exactly the same. Two atrings in every 
respect the same, will pruduce exactly the same 
tone, and arc said to be in unUon. A string half 
the length of another will \ibrate in half the time, 
or make two vibrations for the other one,— each 
second vibration of the shorter one commencing 
with each vibration of the longer one. A string two- 
thirds the length of tiie long string will vibrate 
three times to its twice. Should we suppose the 
long string to consist of 120 parti, and to vibrato 
sixty times in a second, then we may have seven 
divisions of it, with their according vibrations, and 
the number of times which each one vibrates in A 
second, u in the following table : — 



NaniM of 


DiTlsioni of 
the t^iig 
Sarlii«. 


According 

VlOiaLiHis. 


Iloni in a 
SocomL 


First 


1 or 120 






60 


Minur Third 


^ — 100 


« . 


5 


72 


Major Third 


i — y6 


5 . 


4 


75 


Fourth .... 


1—90 


4 . 


3 


flO 


Fifth .... 


y — 80 


3 . 


2 


90 


Minor Sixth 


f - 75 


8 . 


5 


96 


Major Sixth 


f - 72 


5 . 


3 


100 


OcUve .... 


i — 60 


3 . 


1 


120 



These strings, when struck, will produce different 
sounds ; but the vibrations of each will accord or 
commence together at the above stated intervals 
with the original long string ; and they ore, there- 
fore, said to form a concordance, or to bannonise. 
When the strings have not those proportions, nnd, 
consequently, not these periodical concordances, 
they form disconls by the vibrations continually in- 
tercepting each other, and thus jarring or checking 
each other's momentum. 

The above proportions ronstitnte the diatonic 
scale, and are the foundation of all music ; pro- 
ducing the greatest number of recurring vibrations 
or concords that can he had at the Itn^t intiTvals ; 
and, with the addition of five inti;rveninf strings 
that produce half tones, each one being a sharp to 
the one below, and a flat to tlie one above, consti- 
tute ihe mnsical alphabet. AH the stringa together 
form one octave. But tht same diviainns muy be 
repeated on the short string or CO. when its octave 
tvill be 30 ; and this may be again divided, as also 



I 



its octave. Some InBtnimenU contain ten octaves, 
riling one above another j ypt, constnirted on a 
rc^ar acalc, so as to preserve the proportions. — 
The pianu generally baa five, but samrtimca seven 
octave*. 

The strings are not tfana exactly meaanred in all 
inntnimenU ; oecauM the least difTerence, either in 
tbe matcriala of which strings are made, (heir thick- 
uesR or trniion, which is continuiiUy varying with 
the weatlier, makes a dtffcretire in the tone. Tbej 
are, therefore, fixed according to the sound it- 
self, aa determined by the accuracy of the ear ; — 
which is called tuning them. The conitrtictioo of 
most instruments must connequeutly depend on the 
ear; for in many wiad-instruments, in musical 
glassea, and even in a great many utringed instru- 
ments, no actual proportions can bo npphed ; aiiJ 
tlie only means we have of producing the above seta 
of harmonics or octaves, is, by alteriog and adjust- 
ing the instramcnt or tension of the string tiU the 
right tone is produced. In the violin the lengths of 
the strings are varied by the disposition of the fin- 
gers ; and in the flute, the octaves are chiefly pro- 
duced by the manner of blowing. 

1l\w vihratinn of strings is on the same principle 
as that of pendulums ; each string being confidered 
as two pendulums joined together at the points of 
otdllation, and as describing very small arcs. Now. 
«• pendulums of the same length oscillate in the 
same time, whether the area which they describe be 
great or small, so the vibratioa of equal strings will 
be )>erformed in the same time : hence, though one 
string be violently struck so as to produce a loud 
aound, and nnothcr in unison, so gently as scarcely 
to produce any sound ; yet, aa each vibration is 
performed in the same time, the tones will have the 
same pitch, or the strings will be in tune. 

If a pendulum of a certain length vibrate in a cer- 
tain time, then one that is one-fourth the Icnj^h will 
vibrate in half that time ; the time of vibration being 
as the square root of the length. But to produce 
the seme effect in the string, or double pendulum, 
we must work with hslf the length, — or as the pen- 
dolum decreases in the ratio of 1 — 1, the whole 
string must deoreaac as 1 — 2, Now, as the lengths 
of pendulums are measured from the point of sus- 
pension to tlie point of oscillation, this point of os. 
dltatioti in Htrings mustdtpend an the tension of the 
String. When the string is slock, the distance 
between the point of suspension and osnillation, or 
between one of the pegs to which the string is fast- 
ened, and the middle of the string, must be greater 
than when the string is tight. Uut perhaps the 
true principle is, that each string possesses elasti- 
city only to a limited decree; and Ihit when 
stretched tight, a certain portion of its clastic power 
is exerted lengthwise; ond. therefore, when struck, 
there will be less to exert laterally in the vibration 
— it will consequently vibrate in less time. It may 
be poBsible, therefore, to make n string so tight, 
that all its elasticity shall he exerted longitudinally ^ 
BO that when struck it will not vibrate but break. 

" If the lengths ond weights of two chords are 
the same, their times of vibrstions will be inversely 

the square roota of the forces with which they 
are stretched ; and the number of vibrations which 
they perform in the same time, directly as those 
square roots. So also the tension and the weight 
remaining the same, the celerity of the vibration ia 
inveraely aa the sijnare root of the length, or the 
tcDSiOQ and weight, per inch remaining th- sumr, 
the celerity uf vibration is inversely as the length. 



If eight strings be such, thst the number of vibn- 
lions KJiifh thry perform in a given time be aa llie 
numbers 24. 27. 30, 32. 3G, 40. Ah. 48. the aoonds 
of the tint seven will be perceived aa intirc«stn:g fa 
acutcnrsR one above another from (he first to Uia 
last, and will yield the notes from tlic combination 
of which all musical effects are produee/l. Tha 
tone la not aflected by the eitent of the vibrstloai. 
but merely by tbeir time. The loudneaa of their 
sound is supposed to depend on the greater extvnt 
of vibrations. The last of the eight strings will 
sound what is called the octave above the first ; and 
the ssme series may be repeated again between the 
number 48, and its doable 96, and esch note will 
be the octave to its corresponding note tn the first 
inter\'al ; the numbers of vibrations will be 54, GO, 
C4. 72. 80, go. 9G, and it is evident that this senea 
may be continued either down or up without limit. 
All musical sounds are computed to be contataod 
within ten octaves ; so that the number uf vibrm* 
tions in a given time, that yield the gravest notp, 
is to that which yields the most acute, as I to 2-^. 
or 1 to \^2i.*' ^Piaafair't OutiiM* of XatUfH 
PAHiMopAy. 

Large instruments, and long, tliicV, and alack 
strings, therefore, vibrate slowly, or only once ; — 
while instruments of diminutive siie, and very short, 
small, and tight strings vibrate ahote a Ibooaaod 
times ; the former pruducitig grave and deep tones, 
and the latter sharp and acute ; hence that screw- 
twisting and ear-torturing process that attends the 
tuning of stringed instruments ; — and all the variety 
of contrivances seen in musical instrumentJ, which 
are, first, for producing the a1>ove octaves ; and, 
secondly, for playing the tonea longer or shorter, 
when they are called notes, so as to produce sncb 
harmonioos combinatiuua of r^pilarty recurring 
aounds, as we call a /une, an air, or a mtl&djf. 

The above divisions in the length of the origin^ 
long string are fnr from Iwing arbitmry — they are 
even poiuted out hy Nature herself; fur, should a 
rope of 30 or 40 feet in length be stretched 
very tight, and struck, it will not vibrate uuiformly 
between end and end, but will divide itself iaM 
portions ; some vibrating and some at rest,— the 
latter acting aa bridges, or stops to the former. — 
Soppose the length of the rope to be OU ; then the 
IpngtliA of the vibrating parts most be 30, 20. snd 
12. Pur the sounds emitted are the octave, the 
twelfth, or otrlavo of tlte fifth, and the srvrntemth 
major or double octave of the third major of titf 
principal sound produced by the whole rope. It ift 
supposed to be the tendency of strings to more in 
this manner that produces the wild and mc'lodioiu 
harmony of the Eolian harp ; for we not only hear 
the natural &ound of each string, but it-s octavf, 
twelfth, and scventccnlli. " Harmouy (says a 
writer, in the " Edinburgh Review,") is not ao ad> 
vectitiouH quality in sonorous bodies, but is in some 
sense inherent in every sound, however produced. 
Every sound is aa much made up of three compo- 
nent parts as a ray of light is compulsed of seven 
(three) primary colors. In many sunorons bodies 
these sounds may be made distinctly andthl?, as in 
the toll of a great bell, where, amid the vihrvtinns 
of the primary or fundamental note, its 1 2th, and 
17th are distinctly heard ; that is, the note with its 
3rd and ^th, composing the full harmony, are gene- 
rated by the vibrations of what ajipean, to itiaUen- 
tive cirs. to be only a siiiiide sound." S^mriiiing 
of the same kind maybe observed in tlie report trf 
cannon when heard from a distance. When near, 



MAGAZINE OF SCIENCE. 



167 



aU accnniUnr vibrations nre confounded in one cnek ; 
bat wh^D beard from the distance of ten or iwentj 
■dies, " it iti a grave sound, wbich may bt! com- 
^red to A dettrminate muBicol sound, and loslesd 
of being lnsUnt<uieou«, it begins softly, sneltg to its 
rnutiMtt loudorss, snd tbcn dies away growling.— 
Nearly the same rosy be observed with respect to a 
clap of thundt^r/* 

Another remarkable circumstance in the nature of 
wand is. tbdi when >a elastic propaUion of tlie air^ 
pntdacinj; K rfrtnintooe, strikes any sonorous body 
or Btasiesil iusirumenl, which, if struck iu any other 
aaoner, would produce that tone, it communicates 
the sound to that body or initrument. while it 
breaks si^inst, ur passes orer ocberi not in unison, 
vithout producing^ any clfcct. The string! of the 
EoUaii harp are of the same length, and arc tuned 
ia unisun ; if one string is, thcrefure, struck, the 
*hoI« will Tibrate or produce sound ; but if only 
two are iu onison, and one of them be struck, the 
other imlr wilt vibrate. This may be proved by 
v,.--;^,. pi^ea of paper on all the striugs; when, 
'- struck, the paper will immediately fly off 
1 in unidon with it. but will remain nn- 
1 upon the rest. Though the Btrings all 
:tie some combinations of natural concords ; 
fct, «« ibe wind that plays upon them is perpetu- 
ally rmrying its intensity, its sportire sweeps '*pro- 
J — vjiriety and awectff^ss of liormony. which, 
the stillness of evening, may almost be 
._ ., ;i for an unrarthly muair." 
To (his sympathy in the claatic pro)>erties of 
BuUrr it is owing that one thing, and perhaps only 
that one in a room wilt begin to danr^, vibrate, or 
emit sound to one particular note of on organ, or 
any other instrument, while all the other notes have 
ao effect upon it. These corresponding notes are 
Called the key notes ; and such foundation has thb 
n nature, that it is not confined to inanimate ob- 
jects. A dog will begin to howl at one particular 
QOtr. though iodifTcrent to all the rest uf the gamut ; 
tnd nen man himself has the key-note to each of 
tils pAisions : and hence it is, that his soul is so 
noirii nith music, and that he is often compelled, 
c«cn iQ deftancfl of himself, to laugh with those 
Ihit laugh, and weep with those that weep. 






f 

t 



ANALYSIS OF MINERAL WATERS. 

iRjftttMfl/rom pagt 1-49.) 

Tiuic is flonetimes found in water a quantity of 

Uhuncn combined with alkali, and in the state of 

MU. In such waters aeids occasinn a rnagulation; 

M the rosgulum collected on a ftlter discovers its 

klaminous nature by its combustibility. U'ater, 

■U9, somrtlmes contains extractive matter ; the 

pRKOee of which may be detected by means of 

HtnU of silver. The water iuspeoted to contain 

knoaC be freed from sulphuric and nitric acid, by 

Mtts of nitrate of lead ; after this, if it give a 

*nwn precipitate with nitrate of silver, we may 

cnotlude that eitractiru matter is present. 

R':t it is not sufficient to know that a mineral 

r.uins certaia ingredients: ft is necessary 

tin the proportions of theie, and thus wc 

■ complete unclysifl. 

tent .-luriaJ duids ought to be 6rst 

' r ktimaled. For this purpose, a reC 

filled two-thirds with the water, 

- with a jar full of mercury, standing 

rcufiul trouBih. I^et the water be made to 

A quarter of an hour. The aerial fluids will 



^gUglgl^ 



pass over into the jar. When the apparatus is coot, 
the quantity of air expelled from the water moy bo 
deteruiiiied either by bringing the mercury wilhia 
and without the jar to a level ; or, if this cannot be 
done, by reducing the air to the proper density by 
calculation. The air of the retort ought to be core- 
fully subtracted, and the jar should be divided into 
cubic inches and tenths. 

The only gaseous bodies contained in water are, 
common oir, oxygen gas, nitrogen gas, carbonic 
acid, sulphuretted hydrogen gas, and sulphurous 
acid. The lost two never exist in water together. 
The presence of either of them must be ascertained 
previously by the application of the proper tests. — 
If sulphuretted hydrogen gas be present, it will be 
mixed with the air contained in the gloss jar, and 
must be separoted before this air be examined. 
For this purpose the jar must be removed into a tub 
of warm water, and nitric acid introduced, which 
will absorb the sulphuretted hydrogen. The rcsi- 
dnnm is then to be again put into a mercurial jar 
and examined. 

If the water contain sulphurous acid, this previous 
step ia not necesory. Introduce into the air a solu- 
tion of pure potash, and agitate the whole gently. 
The carbonic adtl and iulphurous acid gas will be 
absorbed, and leave the other gases. The bulk of 
tlii« residuum, subtracted from the bulk of the 
whole, will give the bulk of the carbonic acid and 
sul))hurouii acid absorbed. 

Eraporate the potash alowly, almost to dryness, 
and leave it exposed to the atmosphere, Sulphate 
of potash will be formed, which may be separated 
by dissolving the carbonate of potash by means of 
diluted muriatic acid, and Altering the solution.— 
)UU grains of sulphate of potash indicate 36.4 grains 
of sulphurous acid, or 63. G6 cubic inches of that 
acid in the statu of gas. The bulk of sulphurous 
acid gns ascertained by this method, subtracted 
from the bulk of the gas absorbed by the potash, 
gives the bulk of the carbonic acid gas. Now 100 
cubic inches of carbonic acid, at the temperature of 
GO^, and barometer 30 inches, weigh iQ.6 grains. 
Hence it is easy to ascertain its weight. 

When a water contains sulphuretted hydrogen 
gas, the bulk of this gus is to be ascertained in the 
following manner : — Fill three-fourths of a jar with 
the water to be examined, and invert it in a water 
trongh, and introduce a little nitrous gas. This 
gas, mixing with the air In the upper part of the 
jar, wrill form nitrous acid, which will render the 
water turbid, by decomposing the sulphuretted hy< 
drogeu and precipitating sulphur. Continue to add 
nitrous gas ut intervals as long as red fumes appear, 
then turn up tlie jar and blow out the air. If the 
hepatic smell cootinne, repeat this process. The 
sulphur precipitated indicates the proportion of 
hepatic gas in the water ; one grain of sulphur in- 
dicating the presence of nearly 3 eubic inches of 
this gai. 

2. After having estimated the gaseous bodies, the 
next step is to ascertain the proportion of the earthy 
carbonates. For this purpose it is necessary to de- 
prive the water of its sulphuretted hydrogen, if it 
coutain any. This may be done, either by exposing 
it to the air for a considerable time, or trcatiog it 
with litharge. A sofficient quantity of the water, 
thus purified if necessary, is to be boiled for a 
quarter of an hour, and filtered when cool. The 
earthy carbonates remain on the filter. 

The precipitate thus obtained moy be carbonate 
of Umc, of toBgncsiD; of iron, of alumiuo, or even 



168 



MAGAZINE OF SCIENCE. 



sulplwte uf lime. I^et lu 8U)i[)ofl« all of tlieae aub- 
tUncet to be prcKDt tofcthcr. Treat the mixture 
with ililuted muriatic acid, which wiU dissolve the 
whole pxrrpt thr alaminx and sulphate of lime. — 
Dry tbi« residuum in a red-heat, and note the weight. 
7*heu boU it in cmrbonate of Boda, saturate the soda 
with murifttic acid, and boil the mixture for half an 
hour. Carbonate of lime and alumina precipitate. 
Dry this precipitate, and treat it Kith acetic acid. 
The time will be dissolTcd, and the alumina will re- 
main. Dry it and wci^h it. Its weight subtracted 
fram the original weight, giret the proportion of sul- 
phate of lime. 

The muriatic solution contains lime, ma^esia, 
■nd iron. Add ammonia as loog as a reddish pre- 
cipitate appe&rv. The iron and part of the mag- 
oeaift are thus separated. Dry the precipitate, and 
expo«e ic to tJie air for some time in a beat of 200" ; 
thea treat it witb acetic acid to dissolve the mag- 
nesia, which solution is to be added to the miiriatic 
solution. The iron is to be re-diisolvcd in muriatic 
acid, precipitated by an alkaline carbonate, dried 
and weighed. 

Add sulphuric acid lo the mariatic solution as 
long as noy precipitate appears \ then heat the 
eolation and coooeatrate. Heat the sulphate of 
lime, thus obtained, to redness, and weigh it. lOO 
grelDS of it are eciolvalent to 74.7 of carbonate of 
lime dried. Precipitate the magneida by means of 
carbonate of sodn. I>r7 it and weigh it. But aa 
|>art remains in solution, evaporate to dryness, and 
wash the residuum witb a sufficient quantity of dis- 
tilled water, to dissolve the muriate of snda and 
•niphate of lime, if any be still present. What re- 
mains behind is carbonate of magnesia. Weigh it, 
and add its weight to the former. The sulphate of 
Ume, if any, must al^ be separated and wciglied. 
^TuU coniinMrilJ 



MISCELLANEOUS EXPERIMENTS. 

Into a large glass jar, inverted upon a flat brick 
tile>, and containing near its top a branch of fresh 
rosemary, or any other such shrub, moistened with 
water, introduce a flat thick piece of heated iron, 
on wUch, plac« some gam benzoin in gross powder. 
The benzoio acid, in consequence of the heat, will 
be separated, and ascend in white fumes, which will 
at length condense, and form a moat beautiful ap- 
pearance upon the leaves of the vegetable. This 
will aerre as an example of tui/limatioa. 

Introduce a little carbonate of ammonia into a 
Florence Aosk. and place that port of the flask which 
contains the salt on the surface of a basio of boiling 
water : the heat will soon cause the carbonate of 
ammonia to rise nndeoomposed, and attach itself to 
the upper part of the vessel, affording another ex- 
ample of ahnji/e gnhlimation. 

Pill a glass tumble half full of Umc water ; then 
breathe into it frequently; at the same time stirring 
It witb a piece of gloss. The fluid, which before 
was perfectly transparent, will presently become 
quite white, and if suffered to remain at rest, rtat 
chalk will be deposited. 

Mix a little acetate of lead with an equal portion 
of sulphate of zinc, both in fine powder; stir tbem 
together with a piece of glass or wood, and no che- 
mical change will be perceptible ; but if they be 
rubbed together in a mortar, the two solids will 
operate upon each other ; an intimate union will 



take place, and a Jtuid triU hf pnnlvrfi!. If alum 
or Glauber salt be used instead of sulphate of tine, 
the experiment will be eqoally iocccnfat. 

Put a little fresh calcined magnesia in a tea-cnp, 

upon the hearth, and suddenly pour over it as uoch 

I concentrated sulphuric acid aa will cover the mag* 

Dcsia. Id an instant sparks will be thrown oat, and 

the mixture will be cumpUtety ignited. 

Put a little alcohol in a tea-cup, set it on fire, 
and invert a large bcU glass over it. In a short 
time an aqueous vapour will be seen to condeoae 
upon the inside of the bell, which, by means of a 
dry sponge, may be collected, and its quantity as- 
certained. This may be adduced aa an example of 
the formation of vo/rr by combustion. 

Pot a small piece of phosphorus into a crucible, 
cover it closely with common chalk, so as to fiU tho 
cracible. Let another cnioibU be inverted upon it, 
and both lubjeoted to tbe Arc. When the whole 
has become perfectly red hot, remove them from 
the fire, and when cold, the carbonic add of the 
chalk will have been decomposed, and tba kiatJk 
ek«rc<Ml, the bans of the acid, may be eaailj par- 
ceived amongst the materials. 

Let sulphuric acid be poured into a aancer npoo 
some acetate of potass. Into another saucer put a 
mixture of about two parts quick-lime, and one of 
sal ammoniac, both in powder, adding to tbcae a 
very 9maU (juantJty of boiling water. Both saucera 
while Btpanite will yield hmtible gases ; but the 
moment they are brought close together, the ope* 
rator will be enveloped in very vitidle roposirs.— • 
Muriate of aoda, in this experiment, may be aob- 
stitnted for acetate of potass. 
Take a glass tube vrith a bulb in form of a oom- 
^ mon thermometer ; (ill it with cold water, and su- 
pend it by a string. If the bulb be frequently and 
continually moistened with pure Bolphuric ether, 
the water will presently be^oren, even in nrmner. 
Dissolve five drams of muriate of ammonia, and 
five drams of nitre, both finely powdered, in two 
ounces of water. A thermometer immersed in the 
solution will show that the temperature is reduced 
below 32^. If a thermometer tube, filled with 
water, bo now suspended within it, the water will 
soon be a» tjfectually frozen as in the last experi- 
ment. 

Procure a phial with a glass stopper accurately 
ground into it; introduce aome rapper wire, tbn 
entirely fill it with liquid ammonia, and stop the 
phial so aa to exclude all atmospheric air. If left 
in this state, no solution of the copper will be ef- 
fected. But if the bottle be aflerwards left open far 
' some time, and then stopped, the metal will dis- 
solve, and the solution will be colorless. Let ttu 
stopper be now taken out, and the fluid vrill bccoma 
blue, beginning at the surface, and spreading grsda- 
aliy through the whole. If this blue solution hal 
not been too long exposed to the air, and fresh cop> 
per filings be pat in, again stopping the bottle, the 
fluid will once more be deprived of its color, whiA 
it will recover only by the rc-admikiion nf air.— 
These efi'octs may thus be repeatedly produced. 

Take a phial with a solution of sulphate of xbir, 
and another containing a little liquid 9mm< 
both transparent fluids. By mixing them, a on 
phenomenon may be perceived : — tbe line 
immediately precipitated in a white aanai, and 
then shaken, almost as iniiantly rg'di u chfed. 



toNKiiK — l»tlnl«d by U. F»a>ci». G, Wliilo H,ir»e Laii?. Mll« Ku-l ^PubllolioJ by W. BimAiK, 1 1 . l*altfniQtli>t Hv^ 
Commumeaucof. (wtiuh nrc auiwercU .Monliily.) to b« acldrctsed lo ^h^ Editor, at IT. ColtS|[9 Grvw, MUe Eiid Koad. 



THE 



MAGAZINE OF SCIENCE 

R^nd Scf)ool of Srtg. 




170 



MAGAZINE OF SCIENCE. 



• 



c. 



ELECTUICAL EXPERIMENTS AND 
APPARATUS. 

TnK object of the preient paper it to prove, by cj- 
prriment. the identity Iwlwrcn the electric Huid and 
lightniDg. We have already stJttcd thnt they are 
identicml, and in Vol. I, page 333, adduced nume- 
roaa reAsona in cxinfirmation of tht; fact. We shall 
now show upon wliat direct proofR the identity of 
the two rest; am), at tlie same time, explain the 
nature of tome useful electrical apparattts and ci- 
perimentJ. 

It is nec£SMry that when we operate with ac- 
cumalatcd electricity, nud deairo to pa^i a shock 
through a tuhfclauce, that we alioold hnve HOme 
means of holding it steadily, and dlrrrting the fluid 
in the exact line which we deaire. No apparatus is 
80 wrU adApted for genernl purposes of this nature, 
as Ifenlet/'« f^niversal DijiJiar^er, represented in 
Fig. I. A A are two thick brass wires, each termi- 
Dated at one end by a ring, and at the other by a 
ball and socket, which slips on and off, so that the 
inatrament may be naed with or without the balls, 
as required for particular experiments. The wires 
may be drawn out or in by slidinj; tliem through the 
Bockcta B n ; they may be lifted up or down by the 
joints C C, and they have a motion sidcwAys by a 
hall and socket, or other joint nt IJ D ; aU thi» part 
is of brass. The wires are supported upon the two 
glass pillars E G, which fit by their lower ends into 
the wooden feet F F, these lust screwing into the 
stand. The centre part uf the inatruiueiit consists 
of a small table of wood, with a piece n( ivory let in 
the top of it, G, and with a spindle below, fitting in 
the support H, and bound ut any required height 
by the screw 1. The letter J shows a amall presa 
of two pieces of baked wood, with screws to hold 
them together, and a spindle similar to that of the 
tiiblc, for which this pres« is sometimes sabatituted. 
When the uniTcrsal discfaargt*r is to be used, the 
two rings of thr wires are to be connected with the 
opposite sides of an electrical jar or battery. The 
object through which the shock is to be passed, is 
to be placed on the ivory which ia upon the table, 
one ball or wire touching each side of the object. 

Having described this instmmcnt, we proceed to 
prove that nil the etfccts of lightning can be easily 
imitated by tlie ordinary electrical machine and ap- 
paratus ; and, in doing so, it will be necesaary to 
recapitalat« the chief effects of lightning. 

First — Lightning destroys animal and regetable 
Ufe, 60 does electricity. 

Kr. 1. — Procure a mouse and send a strong shock 
khroQgh his body, from head to tail, and the pr>or 
animal will instantly fall dead. To pass the shock 
through the head or chest seldom kills, but if it 
pass along the spinal marrow it always does — 
the tail should therefore form part of the circuit. 
We may be allowed to caution the yonng experi- 
menter, when amufiing himself in electrifying his 
frieucta, never to paaa a shuck along the back-bone, 
it often causes distressing synijUoms fur a long time, 
and may even occasion partial or general paralysis. 

Kr. 2. — The same sudden death will sciae upon a 
Bounder or other small fish, if a very trifling shock 
be passed through it, or a stranger one through 
the water in which it is placed. 

Bjt. 3. — Pass a strong shock from tlie top to the 
root of a balaam or geranium, and although no im- 
mediate efTect will be apparent, yet the plant will 
be effectually kiUed, ti will be evident after a few 
days. 




Seeond-' Lightning often renders 
and disturbs tlte magnetism of such at' 
magnetized. That this is the c 
notoriety. The compau needles on 
often seriously injured from this cause ; 
doea not always occur when a sb( 
through a magnetized needle depends 
cuiTisUince tlwt thn electrical and ma( 
act the one tangential to the other, ai 
lightning potscs close to the magnetic 
in a direction tangential to it, or across 
effect will Uke place. This is fully ex| 
the method of making a magnet descril 
29t^. of Vol. II, in an ardde on electro- 
,^ Third — Lightning destroys metals, ao 
trinity. 

Lightning condncton. the leaden pi| 
and churches, and nther metallic sut 
often seriously injured, if not totally 
when lightning has struck them. Tliii' 
the metallic 5ub»tnnce has not been stifl 
convey awsy the passing duid. There ■ 
experimenta which may be conducted nitk 
electricity, that show the same effect aa wm 
reduction of metallic oayde* ; among 
conducted of which are the following : — 1 

Ex. 4. — Procure two pieces of flat 
about 3 inches long, I^ inch broad 
them a strip of gold-leaf, i an inch or 
Dud long enough to bang out at each moi 
these glasses together with a piece of 
fasten them ia the tittle press belonging' 
vertal discharger, provioualy describeiT 
press in its phioe, and the two balU of ih« 
OS to touch tbe projecting ends of the goh 
psss a strong shock through the leaf and i 
melted, oxydated, and dnven into the surb 
glass. This experiment is illustrated 

Er. b, — Elevate and separate from 
the two balla of the universal dischi 
very Bne iron wire from one to the other; 1 
a shock through them and the wire, and if 
be strong enough the wire will immcdi 
red hot, or be melted. 

£x. 0. — Paint one side of a card 
moo water color called vcrmillion, and 
the tabic of the discharger, re^t the ball 
the diatancc from each other of about an inc 
ing the shock the fluid will run along th« « 
the painted card, and its paaaoge be 
strong black mark on tbe red 
from one hall to the other. If tiw 
off and the points of the wires rested 
the effect will be tbe aane or even 
than when the balls ore ii5cd. Occaaioi 
line will be seen. 

Fourth — Lightning rends to pieces 
and other bodies opposed to ha 
electricity. 

Ex. 7. — Rest upon tbe table of the 
piece of white paper, 4 or 5 inchea 
plncing the two ImHs about 'i iocbes from ea 
send a shock along the surface of the 
it will be rent in pieces along the 
fluid travel*. 

Bt. 8. — Piss the shock throngh a 
the balls of tbe discharger on each tidal 
to it, a minute hole will be pierced thi 
and what is very singular, a l/urr or pi 
is fomit'd on eoch side of the curd, 
stance hns been alleged as a proof that 
two electric fluids : ouc of which crvuei 



'A 

ih« 
goli 
ndi 
e surb 
dby 1 
am M 
targefl 
her; 1 
ndiri 

ndfl 
lalUl 




MAGAZINE OP SCIENCE. 



171 



, and Dtrh praduring tUown burr. It 
I Bmiril. ihiit the pBtMHige of tiic fluid in one 
' is from the poattivc to the nega< 
•Juce but one burr, in the same 
L> ^ piu wuuld da Cliriut tlirough tlie card. 
I ui quwIm; inference, bccaune a Jrili or indrcd 
wl tf fort.'rJ through fl yielding substance, like 
I, by « rarrtiUr motiDii, leavct a durr on IxHb 

M may be evtily proved by a taper bitt and 
>(Ml|i ; or by « «crrw forced througit the cover 
i9ok. or a rtm^r turned round i<t a piece of 
r. That tbis electric fluid is forced forward 
b the ocgntiTC lurfacc is evident from the very 
I of ■ thoclt, and that it hat a circular moUon 
e time, the whole science of electro- mug- 
to prOTC. A shock may be patted 
;li tbrre or four cards at once, and each have 
iWe burr. 

9. — Uang to the celling four or five sheets of 

paper, and pan a shock through it ; the wliole 
< paper will be pierced, without the paper being 

Alixbl(-st degrre oHived. Upon smeUing tbe 
i ttti- paper wlitch has been pierced, it will be 
J Uj\c a combined scent of sulphur aud phos- 
» ; a scent exactly analogous to tliat perceived 
'tuning haa atmck an abject close at hand. 

10. — Place betweeo the two bolls of tho dis. 
ST a amall tump of sugar, and und a shock 
[hit; the sugar will perhaps he broken, if not, 
I •er.ond and a third shock through it, when 
I the shocks have been very weak, and the 
UiT^c, it will not fail to be broken into many 
I. If this experiment be performed in the 

the sugar will give out at the time of the 
y aod fur half a minute afterwards, a strong 
iMriclighL 
. II. — TAe TMmnder Hi/use is oa apporatoi 

ahiiws the cfl'crts of lightning and it^ imj- 
^ Jt is represented in Pig. 3, and consists of 
B^ piieoti of baked wood, made like tbe gable 
Imat, placed upon a wooden stand. A strong 
wltJb a boll at one end and a hook nt the other, 
lowo the upright piere ; it is interrupted in 
r two places, by a hole cut in the upright, 

one inch square and a quarter of an inch 
be aurfocc ; into these holes are fitted fif|0Ares 
od. tbat take out and in very easily. They 
I wire running across them in one direction, 
ai if the squares are placed in one way, tbe 

upright is furuisfaed with a continuous wire ; 

other way, the wire is interrupted, because 
in \a tbe small piece or pieces runs across. 
ttd so as to be continuous, a shock may be 
i di^wti the whole boose, without injiu'y ; but 
her of the pieces ore placed with the wire 
, that pircc upon passing the shock through 
ire would be ihrawn out, showing a close 
jj with the effects of lightning, when it passes 
•a NBpeffect, or rather on interrupted con- 
r. 

, 12.— Pig. 4 reprcsenU T&e BUetricat Obe- 
LAj^i, ^..^. -'a of four pieces of wood, standing 
■h I- tlirt*e Mjip<-r onea resting on 

pftU J lit ball is supported by a moveable 

Af woixl, hke that in the thunder liouse, aud 
Ifae fthodt is passed, the piece is thrown out in 
laoner, and of course lets the obelisk fall. 
h — Lightning sets fire to stacks, ships, build- 
>ko. 

liATe already, in a paper showing the healing 
^f tlrctricity, (in Vol. tl, pogL* :i22.) seen thai 
Mob»t«Dcet may be readily iulluiuvd by the 



spark and shock ; we need not, therefore, dwell 
long u[Kin tliis, yet tbe present notice would be in- 
complete were we wholly to omit an iUoatration or 
two. 

Rx. 13. — iZosin F^rtd. — Tie loosely round one of 
the balls of the universal discharger, or round the 
ball of a common discharging rod, a little loose tow ; 
when tied on, roll it in powdered rosin, and oend a 
sudilea shock through it, when the rosin will be 
infiomed. 

Ex. II.— Fig. 5 shows The Eheirie^l fhrt .■ we 
bare shown it with three cannoDS, but itis more con- 
venient and effectiTe witb four. The cannons and f*»rt 
are of ordinary make, obserring only tbat the fort 
should be of very dry baked wood, nod tlic canuoiia 
hove extra touch-holes made of a piece of paper, 
sh'iped like n funnel, and fixed on with sealing wax , so 
tliat there may he a grealer body of gunpowder than 
they would otherwise hold. The passage of the 
fluid is MS follows : — One side of the charged Leyden 
jar is connected with a chain that dips in a basin of 
water. The chain F also dips in the some water 
by one end, and is connected with the outside of 
tbe cannon A. The 6uid then passes through the 
gunpowder of this cannon to the wire U, and runs 
along this to the next cannon B. It passes through 
the gunpowder here, and inflames it, as it did the 
former ; it has now reached the outside of this can- 
non, end passes by a wire E, under tbe platform of 
the fort to the outside of the lost cannon C, and then 
goes through the touch-hole to a wire G. that may 
lead it away to the Lcydcn jar again ; thus com- 
pleting the circuit, and proving, at tbe same time, 
tbe inflaming effects of the electric Huid and Ita 
great rapidity of motion, as it will be fuuiid that the 
cannons, however numerous, or however far apart, 
all go off so simultaneously as to be beard as but 
oue report. 

CONVERSION OK CARBON INTO SILICON. 
A oiscovBKY has been Utely made, which is likely 
to extend widely the bnnndaries uf chemical science. 
The views of the alchymists, with regard to the 
transmutation of metAls, are now shown to be of 
possible realisation. Chemists have ceased to draw 
any line of distinclioo between those bwlics ordi- 
Dsrily termed metals, and other elirroentary sub- 
sUncea ; j. e. in proceeding throngh the list of 
elements, from oxygen to platinum, we cannot say 
where the metallic property commences. Now 
Dr. S. Browu, of Edinburgh, bos given proof, in 
a paper read before tbe Iloyol Society of that place, 
that the elemetitary body, carbon, can be converted 
into silinon, whirh last substance was, not long ago. 
considered metallic. Observe, this is not the de- 
composition of silicon, or rather the formution of 
it, from n new base, but the proof of tbe absolute 
convertibility of one elementary body Into snother, 
which we must still regard as simple. Tliis grand 
discovery, second to none that has ever been made 
in science, and likely to prove of vast benefit in its 
results to the resources of the arts, is the work of 
a young man — who hnd, however, given proof of 
the greatest powers — c.r j/ede firrculcm. Like 
other great discoveries, it has been preceded by 
such indicative facts as might gradually induce us 
to regard it as possible. We allude to the doctrines 
and facts of isumerisra, which showed that some 
compound bodies, presenting on analysis tbe same 
chemical composition, might yet ditfcr greatly in 
properties. In tliesu cases it was cunceived that 
the atoma might be difr«jrtnlly arranged, or that the 



172 



MAGAZINE OF SCIEKCK. 



compoBiUan of the one body miglil be rcpresentctl 
hy duubliog the Moms of tlic olber, and to furth. 
Tfans. if we bave a body whose compoflition may be 
represented by a b, we may write it i a, or twice 
a h. Now, as our only reason for bclicTiog any 
body Co be simple is, that we are anable to decom- 
pose it, it is quite possible that some of the bodiea 
which we coU simple mij^ht really be compound 
ftod isomeric- But to sum op the fdcts prrseoted 
by Dr. Brown : — Hia late communication is purely 
of a practical character, the author baring retrained 
from presenting what he conceives to be the rntionale 
of the aiDgnlar facu be baa dincovcred, until furthrr 
inTestigntiuni of a similar kind shall hare been 
executed by himself or others. The manner in 
which the author cstabliahes the Isomerism of car- 
bon, and iilicon la Tery simple, and cousists in 
giving a great many processes by which the former 
may be converted into the latter. These are coa- 
Uined in a scries of fire sections. The first treats 
of tbtj production of silicon from free paracyanozen ; 
Uie second, of Uie formation of mixed siUdureta of 
copper, iron, and platinum, by the re-action of 
parecyanojcn ; the third, of the ijuantily of nitro- 
gen Bfp.inited from paracyanozen, when it ia changed 
into nitrogen and silicon ; the fourth describe* pro- 
cesses for the preparation of transparent crystallised 
liliciuret of iron from the poracyanide of iron and 
the ferro-cyanide of potassium ; and the fifth gives 
easy procesacs for the extraction of silicic add from 
ferrocytnide of potnisium by the action of car- 
bonated putau. The last of these processes baa 
been rrpcatLd in the laboratory of the Newcustle 
Medical Sdiool. .ind found to give the result de- 
aoribcd by Ur. Brown.— A/iK»ny Jonmuf. 



ON CHLORINE. 
CilLORi?rB was discovered by Schccic in his experi- 
ments on oxygen, in 1774; be colled it dcpblo- 
gisticated muriatic acid, but it afterwards obtained 
the name of oiy-muriatic add. 

Its specific graiity, compared to hydrogen, Is 
33'3 to 1 ; 100 cubic inches weighing 73-375 grains. 

It ia a permanently elastic gaseooa fluid, liaving 
a pungent and disagreeable odour, and being highly 
iiijarious whtn respired, ercn though it be largely 
diluted with atmospheric air. lu color is a greenish 
yellow. Cldorine is not altered wlien expuscd to 
the highest temperature, which wag proved by Sir 
U. Dsvy, by means of the foUowiug experiments : 

Er. 1. — Provide ■ gloss globe of about \ inches 
in diumcter, baring at its upper port a sliding wire 
passing air-tight through a ground collar, to the 
lower end of which is attached a piece of well 
burned charcoal. At the bottom is a stop-cock 
supporting n pair of brass pincers, in which tlierc 
ia another piece of charcoal. The globe is I'xhaustcd 
upon the air-pump, filled with chlorine, and the 
aiop-cock and sliding wia attached to the extremities 
of a galvanic battt-ry. The charcoal poinU are 
then pushed down, aod retained as long aa necessary 
iu igniiiuu. 

Kr. 2.— To obtain cldorine from bliirk oxyde of 
manganese and muriatic uctd ; provide 4 ounces 
of the osydc, aitd oild as much muriatic acid as 
will make it of the consistcuce of thick cre^m. 
Mral it in a glaM retort, and collrct the ^as at the 
piitwmatic troush. but observi! thnt it is absorbable 
by fold water, and only pattiuUy so hy hot. 

Ki. 3. — From blaek o»yile of mnng'mesc, salt, 



water, and sulphuric acid, lake 6 porta of ttmxmaa 
salt, '^ of the osyde, 1 of water, aud 6 of sttlpboHc 
nctd. 

Ex. A. — Take one volomn of water aati tww of 
chlorine, and the water will absorb the gas. This 
solution is of a pale ytllow color, has an sslnngvol 
taste, and destroys vegetable colors ; hmce its use 
in bleaching, though the gas ii^rlf, when pvrfEctlj 
free from njoisture, has hardly any cflect on then. 

Ex. h. — Take a small piece of phosphoma ami 
pat it in a deflagrating ladle, aod immerse it la 
a jar of chlorine, when it will bttra with gmi 
brilltaoer. 

Ex. G. — Provide a wire, and attach '« pieec «f 
a taper, aod immerse into chlorine ; when Ihr 
brilliancy of the flame becomes impaired, it appear* 
red, throws oR* much carbon, and is nearly ex- 
tinguished. 

Ex. 7. — Vary Ex. 5 by iotrodiicing copper leaf, 
antimony in powder, and a finr other mctala. 

Er. 8.— To make oxyde of chlorine, prooeed w 
follows: — Upon 10 or 12 grains of cbloraie of 
potash, drop a small quantity of sulphuric aiil, 
and stir the mixture with a platinum knifs, hstffaf 
so adjusted the relative quantities of the »a1t aii4 
acid ttiat they may form together a yellow liquid. 
Put thic into a small retort, and heat it by meaoa 
of a water bath to IfiO". Oxyde of dilorine will 
pass ofl'i and may be collected over quicksilver In 
small jars or tubes. The oxyde has nn odonr aome- 
what resembling that of chlorine, but mnch IcM 
irritating and disagreeable. Its taste ta astringeat, 
and not at nil acid. It dissolves in water, formifij 
a lemon-yellow colored solation. 

Ex. y. — Heat gently some oiyde of cbl< 
and it will he decomjtoscd vrith explosion ani 
panslon. Two volumns are enhrgnl into thrrc, 
which two consist of oxygen, and one of chlortac 
it is therefore com]>ofled of 33*5 parts, by 
of chlorine, combim.'^d with 30 of oxygen* 
gas was originally cnllcd cuchlorioe by Sir H. 

Ex, 10. — To obtain chloric add, take a 
of oxyde of silver and water, and pass a ci 
chlorine through it. Chloride of silrrr is p 
which is insoluble, and may be separated by filtri 
The excess of chlorine, which the filtered 
contains, is separable by heat, and the chio 
dissolved in water, remains. It is a soar, 
liquid, producing peculiar compotmdfl, 
chlorate of potash. It fbrms uo predpl 
metallic solutions. 

Ex. 11. — Muriatic acid, (or accordiag lo 
new nomenclature hydro-chloric add,) la a 
pound of hydrogen and chlorine. Mix 
volumns of these gues, and eiposc then 
light, aod the add will be formed. Having aae^te 
portion ready, expose it to tlie direct lolar rays, 
and u detonation will ensue. The same rrsalt U 
observed if it be exposed to the light of the volttie 
discharger. 

Ex. 12.— Chloride of nitrogen. Chlorine tnt 
nitrogen do not nnite directly; hut the coBD|Kmai 
may be obtained by exposiug a solution of nitral* 
or muriate of ammoaia to the action of a currMt 
of chlorine at the tcin|K:rKlure of tlU" or 70^. 1^ 
gas is nbsorbcd, and an oil-like fluid heavier thai 
water Is produced. This ^wuld be experiiaenlsd 
U]H}n with great care, as it is very exploiive. 

Ex. 13. — Ammonia and uhlorinr. >\'hen (hOM 
gnses are mixed, a partial dccumjiosiLion of ths 
furuier cnsuco. Take of amuioniu 10 |i.irt0v ana 
mLx with 15 of chlorine ; 3 parts of nitrufO an 



l:i 



MAGAZINE OF SCIENCE. 



fttnl mumcc of acnmonia is formed. U 
htf iterievliy drj, beat is eToIred, ntid a 
U MJd to traTCne the resad in ivhlch the 
It fonnvd. 

Rr. 14. — CliIortd« of sulphur. Heat ntplivr in 
A£0rinc ; it iibaorin rather more than twice its 
vwjglit of Iho fu, and formi a grtKnub yellow 
i^fidi. cxit^atsting of 15 iiu]j>hur and .'\3'.'i of chlorine. 
U vximlrt nlTocatiog and irrltAtin^ fumet when 
crpOMtt to the air. Ita cpccific gmvity is 1'6, anil 
4ut>Irea aolphnr and pbosphoms. 

Kr, \S. — Chloride of phusphorus, consisting of 

II fhospbonu *nd .'i3-r» chlorine, is procored by 

totlTiBf K mixture of phosplionis and corrosive 

i^btiiialg, or |KrchIoride of mercury. Csloroel or 

pntoddoiridc is left in the retort, and the phos- 

oeabities with one proportion of chlorine 

iftpttiM* over. 

Ar. 10< — Take a jar of chlorine nnd immerse in 
a |«{«cr ^ftitcd in oil of tarpentiuc, and the gas 
i-II btflaine the tnrjienline. 

C mit tn, — CUlurinc must be experimented upon 
Mk frrit care, from its jiangent odour and 
Ltittf; pfDpcrtici ; and it is advisable for 
^rciiinrrs not to cxpcrimeut with tiacb things 
L|d£ of chlt^rine, chloride of nilrogun, \c. 

CUEMlCUa AUATOH. 



AyAl.YSrS OP MINERAL WATERS. 

f Jif^tmmcii/rom pa^ 168, ami concbuUxLj 

ri;-jct to ascertain the proportion of 

iilkalis, if any be present uncora- 

1 j-.r ,1. ..I.-* which may be present, omittinif the 

t, 5UT iliC salphuHc, muriatic, and the Iwracic. 

prop'irttnn uf sulphuric acid is t:aKiIy dcter- 

Satamte it with barytes water, and ignite 

Itate. 100 ^:raiui of sulphnte of barytes 

tndieate 34.0 of real sulpharie acid. 

lie ibc muriatic add with burytcs water, 

precipitate llic barytea by suljihurie acid. 

of the ignited prei'ipitatc arc equivalent 

t ^,Ai-,-: ..f real muriatic acid. 

borocie acid by meaoa of acetate 

>j>ose the borate of lead by boiling 

acid. Evaporate to dryness. Dis- 

ic nHd in nicohol, and tvaporate the 

:" I may be neighed. 

I of ulkalinc carbonate 

^ rxi,^ . L....L^..w<,|^ it, Batiimtc it with 

•crd, and note the nciglil of real acid 

Now 100 gmini of re-ai sulpharie acid 

I21I.0 potash, and 80.0 soda. 

T- 3^1 'lino jralphnte* may be estimated by 

\r snid by means of nitmte of bn- 

vinualy freed the water fiom all 

' ' '' grains of ignilwl sul< 

I Ains of dried sulphate 

:, . Lc of barytes indicate 

ol poioah. 

.i''< U easily irstlmated by cmpora- 

•"g it, to a few ounces (hav- 

I the earthy carboDstes n-ith 

I', ftiiLt {•:>-i'i]>iuting the »ulpliate of lime 

iA weak alcohol. It may then be dried 

■ rilu'H miy be cstimnted by prcci- 

lina by carbonate of lime or of 

^if uu lime be present in the liquid).^ 

(Taint uf the sluniioii, hctited lu tiu-sn- 

IwtfaLe loo of eryBlallixcd alum, or 05 of 



1 

is. 
to 



Snlphate of ma^esiu may be estimated, prori* 
no other sulphate be present, by predpitating t) 
nciti by mt^mis ot a barytic salt, as 14. 7j porta of 
ignited sulphate of barytes indicaLe 7. lli of sul))hat 
of magnesia. If sulphate of lime, and no othi 
sulphate, occompnny It, this may bo dcetim|K>«e( 
and the lime precipitated by carbonate of magnesia. 
The weight of the lime thus obtained, enables us to 
ascertain the quantity of inilphate of lime cantaint 
in the water. The whole of the sulphuric nt^id 
tbrn to be precipitntrd by barytes. This gives tl 
quantity of sulphuric -, and subtracting tho portion 
which belongs to tht sulphate of lime, there remains 
that which was combined with tlte magnesia, from 
which the sulphate of magnesia may be estimated. 

If sulphate of soda be prest*ut. no earthy hitratj^l 
or muriate can exist. Tbcrct'orc, if no other eortll^^l 
sulphate be present, the magnesia may be precipi^^ 
tated by sods, dried and weighed; 2.iC groins of 
which indicate 7.1G grains of dried iulphote 
magnesia. The «.ame process succeeds when st 
pfaato of lime accompanies these two sulphates 
only in this case tlic precipitate, which consist* bt 
of time and magncflla, is to be dissolved in sulpht 
acid, evaporated to dryness, and treated with twl( 
its weight of cold water, which dissolves the sul- 
phate of magnesia, and leaves the other salt. Let 
the sulphaCci of uiagnesia be evaporated to dryness, 
exposed to a heat of 4U0', and weighed. Tbe same 
proce&ses succeed, if alnm be present instead of Ba|S 
pbate of lime. The precipitate in this case. prfllH 
viously dried, Is to be treated veith acetic acid^ 
which dissolves tiie mairnesia, and leaves tlic ulumina. 
Tbe magnesia may be iigoin precipitated, dried, and 
vreighed. If salj^hate of iron be prcient, it may be 
separated by expobing the water to tbe air for somc^ 
days, and mixing with it a portion of alnmina.-^fl 
Both the oxide uf iron, and the sulphate uf aluminiq| 
thus formed, precipitate in the stjite of an insolable 
powder. The sulphate of magnesia any then bo 
estimated by the rules above given. 

Sulphate of iron may be estimated by prccl] 
tating the iron by means of pruasic alkali, havi 
pre viouAly determined the weight of the preciplt 
produced by the prussiate in a solution of a givi 
weight of sulphate of iron in water, if muriate of 
iron be also present, which is a very tore case, it 
may be separated by evaporating the wuter to dry- 
ness, snd treating the rvsidonm with alcohol, which 
diisoKes the muriate, and leaves tbe sulpliate. 

A. If muriate of jiotaah or of soda, without any 
other salt, exist in water, we have only to decom - 
pose them by nitrate of silver, and dry tlie precipl^^ 
tate; for 18.2 of muriate of silver indicate 9.& *^| 
muriate of potash; and 18.2 of muriate of silver io- 
dicnie 7.5 of common suit. 

The same process is to be followed, if the alkl 
line carbonates be present ; only these carbouat 
must be previoosly snturstcd with sulphuric kci< 
and we must precipiUile tbe muriatic acid by memit 
of sulphate of silver inttoad of nitrate. The pre- 
Bcncc i>f snIphatK of soda does not injure the sue- 
oesa of this process. 

If rouriste of ammonia oocompany either of the 
fixed lUkalint sulphates, vrithout the presence of any 
oIh«r snit, decompose Che &nl amuioiiiac by baryl 
wnlcr, expel the ammonia by boiling, prcclpiti 
by diluted sulphuric acid, and saturate the murint 
acid with soda. The sulphate of bttrjtes thus 
cipttate<l, indicates the quantity of mnriute of at 
moni'j, I4.7ri gmins of Miiplmte indicdtini; 07^ 
graiua uf this salt. If any sulphate* br present ~ 



a uo 

m 



i<tfl 



^^ik 



MAGAZINE OF SCIENCE. 



the ftolntion, they ouglit to be previously separHted. 
If common salt be accompaoied by mDriale of 
lime, mariate of nos|^eii8, muriate of aluniJua, or 
inoriate of iron, or by all thcac together, without 
any other salt, the cartba may be precipitated by 
borytes water, and r«dis8ol?cd tn muriatic acid.— 
They are then to be separated from each other by 
tlie ruin formerly laid down, and their weight, be- 
in^ determined, indicates the qaantity of CTcry par- 
ticular earthy muriate contained tn the water. Fur 
50 grains of lime indirat^ 100 of dried muriate of 
lime; 30 grains of magnesia indicate 100 of the 
muriatic of that earth ; and 21. H grains of alumina 
indicate 100 of the muriate of alnmina. Tttc barjten 
ij to be separated from the solution by sulphuric 
acid, and the muriatic acid npelled by heat, or 
saturated with loda ; the common salt may then 
be ascertained by evaporation, subtracting in the 
last ease the proportion of common salt indicated 
by the known quantity of mDrintic acid, from which 
the eartlis had been separated. 

'%'hen sulphatf?9 and muriates exist together, they 
ought to be separaled either by precipitating the 
snlphales by mcana of alcohol, or by evaporating 
tlie whole to dryness, and dissolving the earthy 
muriates in alcohol. The salts thus sepnratcd may 
be estimated by tlie rules already laid down. 

When alkaline and earthy oioriatca and sulphate 
of lime occur together, the lost is to be decomposed 
by means of muriate of barytes. Tbe precipitate 
ascertains the weight of sulphate of lime contained 
in the water. The estimation is then to be oon- 
dnctod as when nothtug but niuriutrs are prearnt, 
only from the mnriatc of lime that proportion of 
muriate must be deducted, which is known to have 
been formed by adding the muriate of barytea. 

When muriates of soda, magnesia, and oluniLaB, 
are present together with sulphates of lime and 
magnesia, the water to be examined ought to be di- 
Tided into two equal portions. To the one portion 
add carbonate of magnesia, till the whole of the lime 
and alumina is precipitated. Aacertain tbe quan- 
tity of lime, which gives tbe pro|H)rtion of sulphate 
of lime. Precipitate the sulphuric add by muriate 
of barytes. This gives the quantity contained in 
the sulphate of magnesia and sulphate of lime ;— 
flubtroctiog this last portion, we have tbe quantity 
of sulphate of magne&ia. 

From tbe second portion of water, precipitate all 
the magnesia and alumina by means of lime-water. 
The weight of these earths enableii us to ascertain 
tbe weight of the muriate of magnesio and of aluminu 
contained in water, subtracting that part of the 
magnesia which existed in the state of sulphate, as 
indicated by the examination of the first (wrtiun of 
water. After this egtimotion, precipitate the suU 
phuric acid by barytes water, and the lime by car- 
bonic acid. The liquid, evaporated to dryness, 
leaves the common salt. 

6. It now ouly remains to explain tbe method of 
ascertaining tbe proportion of tbe nitrateH which 
may exist in waters. 

When nitre accompanies sulphates and muriates 
without any other nitrates, the sulphates are to be 
decomposed by acetate of silver. The water, after 
filtration, is to be evaporated to dryness, and the 
residuum treated with alcohol, which disaolves the 
acetates, and leaves tbe nitre, the quantity of which 
may be easily calculated. If an alkali he present, 
it ought to be previously saturated with sulphuric 
or muriatic acid. 

If nitre, oommOD salt, nitrate of time, and mu- 



riate of Lime or magnesia, be present together, tlM 
woter ovght to be evaporated to dryneaa. and tlin 
dry moss treated with alcohol, which takes np tha 
earthy salts. From the residuum, redissoWed la 
water, tbe nitre may be separated, and i^lcnlated as 
in the last case. The alcoholic solution is to be 
evaporated to dryness, and the reaidumn redlsaolred 
in water. Let us suppose it to contain muriate of 
mogncaia, nitrate of lime, and muriate of lino^ 
Precipitate the muriatic add by nitrate of 
which gives the proportion of muriate of 
and of lime. Separate the magnesia by means of 
carbonate of lime, and note its quantity. This give* 
the quantity of muriate of magnesia ; and sabtnct- 
ing the muriatic acid, contained in that salt, fnm 
tlie whole acid indicated by the precipitate of ulver. 
we have the proportion of mnriate of lime. Lastly, 
saturate tbe lime added to precipitate the magnesia 
with nitric add. Then precipitate the whole of tha 
lime by sulphuric acid ; and subtracting from the 
whole of the onlphate thus formed, that portion 
formed by the carbonate of lime added, and by the 
lime cx^ntained in the muriate, tbe rcaiduum gives 
ua the lime contained in the original nitrate *, and 
35 grains of Ume form 100 of dry nitrate of Ume. 



ENGRAVING. 

rAuuoNM/ /rum pag* 111^ 
Next to the tools necessary, it is advisable to 
olfer H few remarks npou the materials employed. 
The chief of these is, of coarse, the subat&noe to be 
engraved upon, cither copper or steel. Plates u( 
thcsi; metals, of various sizes and Uiickxteaseo, ore 
prepared ready for the engraver by persons who 
make it their sole employment ; and those who ore 
able to procure them thna prejiared, will find It 
infinitely better to do so than to prepare the plates 
themselves; but ^oald they live far off in the 
country, or for other reasons desire to prriwv 
their own copper-plates, (for steel, tliey will, per- 
haps, not attempt,) the following observationi msy 
guide thcra : — Let them procure a sheet or piece of 
thick copper, the thickness (if a small plate) bong 
about equal to that of a thin mill-board, or (bv 
cards pasted together. Let them carefully 
and polish both sides with und, emery and 
or charcoal ; wiping this off carefully that do 
may remain, let the plate be paased two or tbrta 
times through a flatting mill, or wanting this, let it 
be planished by a tinman, directing him to keep U 
perfectly flat. When this is done, and the oopfer 
thereby hardened, let one surface be rubbed oU 
over with a piece of «nake stime ; a piece of Aom, 
Jiiw slate, or lithographic stone will do as wrll. 
When tbe plate is thus made smooth, and the 
inequalities of the hammer arc removed, mb U 
over in the same manner with a piece of fine diar* 
conl and oil; any bark, knot, or grit in tht 
charcoal being first carefully rasped off" it. Inolead 
of charcoal fine washed emery may be used. Finally, 
the plate is smoothed around the edges with a pUne 
or file, and pulisbed with whitening. It will no« 
be tit for use: a great deal of tbe success of tbe 
after operation will, however, depend upon <h( 
quality of the copper, as well as the prvporatioti of 
it. Another method by which a plate may be mods 
at once, is by the electrotype process. A plate, ii 
a pattern, being first procured, another pUte cnsf 
be deposited ujion that, which being removed, I 
secuiul ajid a third plate la like maniker lusy (S 
CA&ily be made, and if the opcraboD has been wtU 



10 jHF 



MAGAZINE OF SCIENCE. 



175 



la AC 



conducletl, nil will be of excellent quolityi and 
ciMt but a trifle i (the whale procesn of the elertro- 
t|pe will be foand ia Vol. I;) indeed thou&ands of 
pUtev are now made in Ijondon by this process. 

The next material is ticking yruund. The oae of 
it b to Uj a ground ujwn the pUte prcTious to 
clcMog it, oj afterwards desaribed. It may be 
bottf hi along with the platea. or it may be made by 
tW following receipt, and which, by experience, we 
kaow may be depended upon. The prescribed 
qaauUty will make enough to laiC for a long period, 
ftud co^er a great nainber of plates: — MeU together 

1 oaxice uf white wu, 1 ounce of aiphaltum, and 
ft qoiirteK of an ounce each of commoa pitch and 
Bargundy pitch ; let tlic wboto boil ten minutes, 
tb«n pour it into cold water, and mould it into a 
ball with the hands ; when cold^ tie it up id a piece 
of tilVi or tafTeta. 

Bordrring wax la • substance oaed to form a 
ridge around the plate when it hat been etched and 
ia about t^i be biuen iu by the acid. Ita only use 
to prevent the actd from running off at the edges 
ttie plate ; common slioo-makers' wax will do 
well ; so will glaxters' putty, though the 
ftkU<ming ia most naiully employed. Aa it ia not 
mat^d when in use, a stock of half a pound will 
last for yean : — Melt together 2 ounee« of rosin, 

2 ouncca of common pitch, and I ounces of yellow 
bBtei'<wax ; when melted, pour the mixture into 
edd water, and as icon as it is sufficiently cooled, 
Imead it well with Uie bands. 

Aadt required. — It is adrisable in procuring a 
•apply of add for biting in, to chooae the stroDg 
Bitric acid, and not the common aiptaforti* ; atrength 
lur strength, it is but little dearer, and the en- 
gmTer knowing the article he is operating with to 
be of first quality, can proceed with greater confi- 
dence. It should be diluted only when wanted, 
•nd ID a degree according to the nacure of the 
subject— this practice atone can teach. 

Brutunrirk blark vamiMk is purchoseablc at most 
Mspectable oil shops. Its use to the engraver is to 
tt^p otti, that is, to cover over false lines, and other 
daisetaf previous to bitine in ; and alto during this 
part of tbe process, when a portion of the plate is 
Utiea in enough, the rest of it rerjuiring a further 
iOtioa of tbe acid. To be good, Brunswick black 
aboold dry in three or four minutes ; it may be made 
by diaaolving aspholtum in spirits of turpentine. 
If too thick at any time, it is to be diluted with 
»I>ints of turpentine. This Liquid must therefore be 
in readiness, not only for the above, but other pur- 
poses, olterwardi described. The Brunswick block 
rsmiah is to be laid on with a camel's-hair |>cncil. 

A irax taper Is the last material required. The 
intention nf it is to smoke the ground of the plates, 
preriooa to transferring the picture which is to be 
eicbed upon them. The taper adapted to this pur- 
pose is that which ii white, very long, and about 
the thickness of a goose quill, sold nt oil-shopi for dd. 
Procure one of these tapers ; if the weather be cold, 
soak it for a few minutes in luke-warm wotcr, draw 
it out in length, wipe it dry. and fold it up or else 
rut it into eight equal pieces, which are to bo twisted 
together, furming us it were a candle with eight wicks. 

A dabber is also wanttrd ; this may very easily be 
made by the artist, as it consists merely of a hand- 
fel of wool or cotton wadding, tied up in a piece of 
silk ; some persons put inside and behind the wad- 
ding a piece or two of ttiff card, cut of a round 
ism, in order to make the dabber keep its shape 
betteff bat this is bjr no means necessary. Tbe 



dabber is used In llie Arst process of laying tbe 
ground evenly upon tbe pbte to be etched. It is, 
therefore, indispensable. 

Ad oil rubber is made of a long strip of woollen 
cloth or flannel with the sclrage to It. Take about 
two yards in length of this list, and roll it up tightly 
tike a ribbon on Its roller, so that tbe selvage shall 
form an even flat surface. Tie it tightly together 
and keep it for use ; it la Taluable in cleaning off a 
plate, after the scraper, burnisher and charcoal has 
been used upon it, it is rubbed over the psrt of the 
plate requisite, together with a little sweet oil. 

Tbe writing engravers, and those vrbo execute 
mathematical engravings, often require little trifles 
in addition to the above, but as they urc only of 
partial use, and not even absolutely necessary, we 
have not (thought it requisite to mention them. 
These are, indeed, all the materials requisite for the 
most extensive business, costing, with the cxcepiiun 
of the copper and steel pUtcs, altogether, both tools 
and substances, not more than 6t. or 7». The next 
paper will explain the process of etching. 

AWe- — Coppsr and *iw\ plale« for sngravcn, and alK> cU^li- 
tDg iroimd, may b« purcbasvd of Mr. I)ugbe«, Slio« l^n*. 
l^mcTin ; or uf Mr*. L^rgc. DttSiiSlr»el, Fetter LaDC, Londoo. 
A plAto of cop|N*r. the itM of the (iruilleat card. eo«tf t^U. 
Next iiu cord. Id. A plot* Rboai iho tiiv of oa« P^ss of 
this liook may b« Xi. or 3#. tJ. The avTieral pric* U 3«.lr tb 
weiglii. SU>el double the price. A ball of etcbtag graund 
coatji If. Engraverft' looiii may b» boaght of Mr. Kntghl, 
Koilar Loiw ; Mr. Fenn and Mr. Buck, Newfal* Slroet; nml 
Mr. HolUalTr). Charing Crosi. HravcrB are from Zit. to &(. 
pocli . haiidlea to ditto. Id. A tfamisbtr. Ij. ScraiMr. 3$. (kl, 
HtclilRf Deedlo, Bii Saod cuihlon*. of varkraa piiois— oua 
coitius ti. la ftl for ordinary occailoiis. 

FLAT mON WIRE ROPES. 
Round iron wire ropes have for upwards of two 
years been successfully used in the collieries on the 
Continent. Another improvement in these ropes 
has been mode, which will render them still more 
useful. M. Louis Goens, manufacturer at Ter- 
CQondc, in Belgium, has obtained a patent tor Jiat 
iron wire ropes. This cordage, which resembles in 
a great degree flat hempen ropes, possesses extra- 
ordinary strength. When properly applied, it will 
last twice or three times as long aa the ro{>cs in 
present use, snd yet the new rope costs a fifth less. 
Independently of these advantages tbe flat iron wire 
cord is more flexible, leu bulky, and a great deal 
lighter than the ropes now used. The latter fact 
deserves the serious attention of mine proprietors 
espedally, for a great quantity of power is now un- 
protitably employed in deep shafts in bringing up 
the weight of the rope alone. The first of tliese flat 
iron ropes manufactured by M. Unens, were applied 
by Messrs. Picard, Davigiton, and Co., proprietors 
of the coal mine of La Bonne Fortune, near Ans, 
where they are now working, and give great satis- 
fscLion. Those gentlemen were the first mine pro- 
prietors who employed the round iron wire ropes. 

POLARIZATION OP LIGHT. 

To tki Bditvr, 
Sin.. — In the interesting article on the polarixation 
of light, recently published in your Magafine, 
there are two or three obserrations which ba»c in- 
duced roc to solicit further Information ; in doint; 
so, I would remark that it is a subject to which I 
have given some atlenlion, and that I have had con- 
aiderable experience in the use of an oxy-hydrogen 
pulariscoiw. I make these remarks that it may not 
be supposed that I ask idle questions, or that I seek 
lufoxmalion tg be procured, by reading the ordl- 



176 



MAGAZINE OF SCIENCE. 



narjr trcatiiifs on the subject. In the artick in 
quuHon it is stated tbnt ■ Nicol'iv prism is the best 
ttiulyziDg medium, uid a Jnwinf; is ^iveii in illus- 
trmtion. 1 am foWj awaro that it \a far superior to 
erery other Gualyiin;; npparstuA in ordinnry csprri- 
iu«nt, but I cannot conceive how it ia applied to the 
oxy-hjrdrogea polari scope. 

Now >vbat 1 would particnlarly uV l«, irAe/An- 
or not such an ntitrument hat been constructed ? 
And if ID. where can it be seen, or a particular de- 
scription obtained ? 

]t is also stated that polarization ib best cffboted 
by reflection ; but I bare beard that oxy-hydro^n 
polariicopes are mndc hy Carry, in the Strand, in 
which the light ia polarized fay tranamisEion through 
a bundle of glass pUtea, and that the colors are 
morr brilliant than those produced by the reflecting 
polariscopei. Can ycni infnrm me if this is correct ? 

Agnin, it is stated tliat the light is also annlyzM 
by being transmitted through sixteen plates or Alms 
of mica ; liut tlii« mica is not the mineral in its 
natural condition, it is prepared in some way be- 
fore it is fit for experiment. Can yoa inform ms 
in what way it is prepared ? e. w, 

r.S. — Is the drawing (Fig, 1. page 113) made 
firom an instmment, or ia it ■ design for one ? It ia 



I rery onlika the instrameots I hare seen. Wliy is 
the light made to pasa through three leases ? 

[The article on the polnrisatioa of light we atated, 
I in the comfflenccment of it (sec pSge 3?). to be 
written by Mr. Guddard. the inventor of the polari- 
acope afterwards described. The original wiU lie 
' found in a recent part of the *' Transsctions of the 
! Society of ArtP." A Nicol'a pijura is not men- 
tioned in connection with the pobrisrnpr, but as 
explanatory of the general remarks which precede 
I the deacription of that instrument Tlie polan- 
I scope has been constmcted, and was oscd far a 
considerable time fur public exhibilioa at "The 
Adrlaidc Gallery." Whether reflective or traoa- 
{ niitting poloriscnpes, He, ore best, ia a mere matter 
^ of opinion. The reason why two lenaes arc often 
combined to act ai one in rarioua optical inatru- 
I meota, is because the sphcricnl and chromatic 
j aberration of two lenses is one- fourth only of that 
produced by a single lens of the aame focfu ; 
I therefore Mr. Goddard has very Judiciously doublMl 
' the lenses in the eye>piecc of the instrument : iha 
lens nearest the light is the better to conccntnte 
the light upon the sclcnite or other poUriaing 
medium . We regret that wc do not know the prepa- 
ration that mica undergoes, or if any, but from th« 
natora of the auhatance «c ahould think not. — kikX 



NOTCa ON THE MOITTB OF flBPTBMBER. 



rreatkeral 


ThfrtmmiHer- 


Jrmget^flfk- 
liarvmeter. 


Rtiin M 
iiwhet 


LOKMHf 

Kpiitaraea,,.. 
PvWIK 


59 63 

at 


aoo9 

iQtti 


4»e 

1470 

3^1 



ANIUATRO NATUiLK. 

In the eariy part of the month the Swallow sines, 
in the latter part of it it Ukfta its departure to 
warmer rlimrs. The other sommer birds are also 
gone from us — broods of youn^ Goldfinrhes nppear 
— the Linnets congregate. Few T^-inter birds viiit 
«s till the fnllowinK month, yot we may see In Sep- 
tember tlie Woodcock, the Fieldfare, and the Ring 
Onael. The Stormy Petrel ventures furtlier south 
than is her wont in bri|>hter and milder weaUier ; 
while many other sea birils change their habitation, 
the Sea Gulls— the Manx Puffiu, and the Solan 
Goose. Owls are more noisy in this month tlxan 
before. Mnny of the songBtcrs of the spring re- 
sume their vernal notes, though with lees brilliancy 
and conatancy tlwn at an cariier pcriwi. The note 
of the Woodlark ia now in its greatest perfection. 
The Robin, who has been emphatically called the 
Brumal Songster, begins his sweet song on the ap- 
proach of the cold. The insect race begins to feel 
the cessation of summer's heat; Butterflies and 
Mothaarc Ic«s abundant ; the Beca, AnU. and Wasps 
more languid. Many Flies b«!come blind and die ; 
yet a few other tribca of insects abound still more 
than during the hot weather. The Earwigs ore 
found in every garden, and the Spider'* weba hour 
on every bosh. 

VBCETAnLK KINGDOM. 

This dejMirtmcnt of nature feeU the cflTecU of a 
dechnmg and varying temperature, of heavy deira. 
und prolonged darkness. The gardena and the 



L«oo«..Pria.PJ l,y » K..„-;. S. Wh.,. „.>« Uo«. M,.p K„j._ra 



hedge-rows are still gay, bat their gayncwtsofa 
different character. Red. white, and blue colors ta 
flowers are much les« abundant than at an earliir 
season, and yellow flowers take their place. By flv 
the greater number of the compound flowers ar« 
yellow, and this is the seaman of their greatest 
abundance. Tlie Hawkwecd — the Marigold anJ 
the Aster are well known. The splendid Uohlla, 
(pronounced Dal-e-n, not Dale-c-a,) is now in Call 
flower, and there are no lesa than a thousand «•• 
rieties of it, of almost every color j a bhic, a green. 
a brown, and a black excepted. Of native plants wg 
may collect, among others, the Clematis Til 
common in the chalky coantlea ; Ballotta 
abundant in the south of England, but rare, if 
unknown in Scotland — Pamassia palustrim a beaa- 
tifut snow white mountain plant. The Iryolsoll 
in flower, so are the Foxgloves — the tribe of tbs 
Mints — the Thyme — the Vervain, and Uie Arbutus. 
The trees put on their autumn tints, their fine grim 
chanties to the sickly yellow, or the go^^couar«Jt 
and intcnninglud as those colors often are, poitico- 
larly in the Horibr-cheennt. render bjr contn«t dit 
grove almost as beautiful as in the apnng. 

OARHKNIKO OPEnATIOXS. 

In the decline of the year, the chief occoptr__ 
of the gardener is to gather his riiwoing crops, and. 
to clear away the plants as they decay in lh« 
borders. It \\ luirdly yet time to be^n pruning 
and transphintlng. Watcting the borders will, om 
account of the dewy nights, be leas neoessary ; baC 
covering the melon beds in the evening, and taking 
care to close his conservatories, will require his 
attention. The cuttings of nnmeroas shrubs msy 
be planted out, nnd the seeds of many biennials 
sown, that they may blossom during the foUowia^ 
year, snch as columbine, agrimony, and chelooe. 
LawQB and grassy glades shoold now be repaired 
where necessary; and towards the end of th* 
month evergreens transplanted and prtmed. 



wytfafflh-j «>i^.v.~a.;:t7.rs:is:z::;rn:'::-^:i^iT.^^;T^^^^^^^ 



THE 



AGAZINE OF SCIENCE, 

and ^cbool of ^xt«. 



SATUBDAV, 5EPTEUBKR 4. 1641. 



[Ud. 



Cj 



1 y 




LEGGETT'S CHEXflCAL COLOR PRINTING. 
Fig, 1. 



Z2= 



n 



^=^ 




ia.-~Ko. XXI II. 



17S 



MAGAZINE OF SCIENCE. 



t-EGGETT'S CHEMICAL COLOR 
r PRINTING. 

Most of ub hare admired the beontifnl coloretl 
cardit show boards, nnJ imall arliclcs of a similar 
de«cripttoo, which bAve appeared within this je^ror 
two in London, iu which the colon are graduiJl; 
Mtftened into each other, nnd made to harnmDixe to 
exquiuiely with each other. Aa the method by 
which such an effect is produced has jiiixzled many 
a ooc. and iff besides a singalar. ti novel, and per- 
fectly scientific appUcnlion uf chcmittry, wc arc gtid 
to accede to the rrquest of several correspondents. 
Rod give the process entire ; and to do this the 
more accurately, we arail oorselrea of the word« of 
the patent, and have beaidea figured the machinery 
described in it. It is the patent of Mr. L<-Kgctt. 

" This Invention consists, first, in a new printing 
ink, to he applied to the purpose of printing in co- 
lors -, to ifiiicb the required color ia given by certain 
^emicftl re-agents. Secondly. — In the mode of 
applying the said re-agenU to prints or patterns, 
printed with the said ink. Thirdly, — Certain oia- 
chinery for that purpose. 

" A quantity of logwooil chips are boiled, for one 
hoar, in eight times their weight of water, (soft 
water is brat ;) tlie liquor ia tbrn drawn oflf, and 
■trained through a hair sieve. The chips are again 
boiled, for two hours, in another portion of water, 
of the same weight as the first, and the liquor is 
■gain drawn off nnd strained. Tlie two decoctions 
■re then mixed together, and a quantity of English 
verdigris, one-thirtiuth tlic weight of the logwood 
chips, is mixed with water, to the consistence of 
cream; the whole, or part of it, it then poured 
gradually into the decoction, adding it till the co< 
loriog matter sinks to the bottom ;'~-thc precipitate 
being of a dark grey, or blue-blark color, and tlie 
anperuatant liquor is clear and colorless. Tlie au- 
peruotant liquor ik now drawn off by a syphon, and 
the precipitjite is placed on a filter, made of fine 
cotton or woollen, in order to drain off and evapo- 
rate any moisture that may remain. When dry. it 
may be ground with oil, or any other liquid, ao- 
cording to the usual method of making printer's ink. 

*' The print or pattern, whether on copper, steel, 
wood, or stone, is printed in the usual manner witJi 
this ink. Then, to those parts of the print or pat- 
tern, which, if it were a painting, would be colored 
yellow, is applied a weak sululion uf vcgetabit acid, 
or any acidulous salts, (bi-tartrate of potash, or 
tartaric acid, is best,) which will cliangetbe neutral 
grey of the ink to yrlluw. To thoae parts which 
are to be red or orange, a weak solution of vegetable 
acid, or any acidulous salts, is appUed. (oxalic acid 
is best.) which will change the neutral grcj of the 
ink to red or orange. To those parts intended to be 
pink or crimson is applied a solution of very dilute 
mlphuric, or other uiioeral acid, which will change 
the nentral grey of tiie ink to pink or crimson. To 
those parts which are to be colored tiluc or riolet is 
applied a solution of nitro-muriate of tin, or of 
alum, which will chongc the neutral grey of the ink 
to lilac or riolet. To those parts which are to be 
blue, n solution of bi-corbonate of ammonia, or 
other alkali, is applied. To those parts which are 
intended to be purple, a dilute solution of bi-tartrate 
uf potash, or other vegetable acid, is applied first, 
and afterwords a solution of thu alkalies, above 
mentioned. If a very delicate pink is required, 
the ink may be made of Brazil chips, instead of 
logwood chips. 



** The chemical re-agent* nay be applied with* 
common hair pencil, or by either of the foUuwing 
processes, which constitute the second part of thia 
invention : — 

" Blocks are formed, similar to those used by paper 
stnint-M, for printing silks, fltc. A bloi-k being pro- 
vided for each color, those parte of the drawing, 
which arc required to be of the same color, are left 
In relief on the block set apart for that color ; aui 
blocks, being provided with the re-agents above men- 
tioned, are applied in succession to the print or pit- 
tern . The following is the second of theie proceuea : 
The print or |»attern is copied on thin aberta of 
metal, paper, or other substance. A sheet uf netal 
is provided for each color ; and those parta wbi^ 
are required to be of the same color, are cot out 
with H graver, knife, or other instrument. Tlir 
sheets arc placed over the prints, and the re-agent 
is applied with o roller — a separate roller being pro- 
vided for each re-agent. The roller is a cylindrical 
block of wood, covered with felt, of the kind con* 
monly used for hatting-blocks ; it is fastened to the 
block by smoll metal pins, or by dissolved ibell-Ue. 

** The tiiird part of tiua invention in the macU* 
nery for applying the re-agents, which is 
applicable for original colore ; and the paten 
dettcribing the machinery, oses the word * coli 
in place of ' re-agent5.* 

*' Pig. 1 ihowB the machinery, with the roller R| 
receiving color. Fif. 2, shows It passing over tttf 
metal plate. There Is a platform, upon which 
workman stands. B is a vrinch handle, that 
the pinion C, which ia fastened ou the wi 
shafY, The pinion C turns the lorge wheel D, 
teeth of this wlicel take into the pinion E, an4] 
this means the wheel F is turned. The whi 
works tlie rack G, by which tlie irregular rod 
moved. Another pinion ia on tlie same axis 
pinion E, and the wheel F : which pinion has 
teeth, which are dividrd into seta of four, a 
being left between each set ; it turns the whi 
by which means the pinion J, on the same axis, ii 
also turned. The pinion J turns the toothed «h«>| 
K. which tarns the Urge dram or narrow cyliadarif 
by the connecting rod M. 

*' The prints or patterns to be colored ore ptsat 
on the cogs N of the dram L. The metal plata 0« 
(shown in Fig. 2.) is fastened totheft.ime V- TbH 
frame ia raised by the quadrant Q, after the colons^ 
roller R has passed over the metal plaU.*. in or^if 
that a fresh cog may come under it ; and diumi;tlis 
time occupied in raising the frame P, the culuniij 
rolltir is moved, (by the irregular rod II, to nhaik 
it is attached,) on to one of the tables S, io onW 
to take a fre»h supply of color. The color is spr*d 
over the tables S, by the feeding rollers T T. wtorb 
are moved backwards and forwards by studs on tbs 
irregular rod H, which wnrk in the guides U of ibtf 
feeding rollers. The feeding rollers take the oobl 
from the colora beds over V V. 

" It will be seen that theooloring roller Knnaol 
descend so low as the metal plate, eicept uhea thr 
raiacd parts of the irregular rod rest ou the fsp- 
porta X ; sufficient pressure is g:iveu to the coloriii| 
roller by the weight W. 

" The quadrant Q. is worked by the rod Y, »ltf 
rod is moved one way by the'spriog Z, and 
other way by the lever A and B, which lerert 
moved by two tappets on the wheel F. 

" The cobring frame is supported by rods, pW 
vided with pins, which step into grooves in the ru- 
lers 1 and 2 ; motion being giveo to the roller t 



MAGAZINE OF SCIENCE. 



179 



9 nf treth, nn the side of the Urge wbcel D, 
to the teeth of thitt roUer, nad are lo tr- 
uit tbey commcQro acting on the teeth of 
'f u soon as the lut of the series 4. quit 
of the pinion K. Tlie motion ii comniu- 
kom the roller 2, to tbo rolter I, by an 





CTING THE ORK IN LEAD MINES 
UTAiNlNG GOLD AND SILVER. 

Dttifol riperimrnti of M. Becquerel on the 
of elecCro-chcmical action to elfcct the 
I tii IcJid anil silver in the galena, containing 
nUer, have deinonstrateti the possibility 

6^ electricity in the mauagement of the»e 
\it vmluable discorery bu indeed been 
dopted OD a Urge aode by M. Decqucrcl, 
Mrimentol manufactory that he baa eatAb- 
Ptria; hot, aa ia often the case in inven- 
;reat importance, mnnj yejira will probably 
Coro bis system is nniversally adopted in 
Sag of lead mines containtug silver. M. 
b1 observtis, in reference to the method of 
the metal at present pnriued : As a pro- 
tbe anriferouH and ailver lead mines in 
' of Baden, I have carefully attended to 
proceaaes that are generally adopted, 
DOfiTicoed of the possibility of obtaining 
prodace from the mines by impruv- 

lenralioni tbat I have made, may be of 

to the icMcra or proprietors of lead minra 
silver or gold. I will mention them in 

, puraiting in detail the method of work- 
mines that I have superintended for ten 

[any of these mines are very rich in silver 

to the manner of washing the ore. By 
in which the process is now executed, it 
that a cooaideroble quuiUty of the ore is 
the portion lost is that whicb is of the 
rilue, the snlphurct of silver. 
Hd and lilver galenas have in general for 
a very hard qunrtx, in which are irregu- 
Kdded sutphnrets of silver, \&id, iron, sul- 
tMrytea, or cwbonate of iron, iiiiJ also ^uor 
be raricty of aulphurets that 1 have just 
contain gold, but Ln such a state of 
t it is invisible in a microscope, and 
rcry attempt to analyse it ; yet gold does 
it is found in considerable quantity in 
the silver. The ore broken into pieces of 
to five centimetrea, ^Is by degrees into 
in which the stampers work. A current 
pBBHt through this trough, which is 
front by a very close iron grating. The 
of the stampers must be continued for a 
lo reduce itie ore sufficiently small to 
passing through tlie grating, and being 
long canals calted Ubycinths. where it 
at a distance further or nearer in pro- 
•txe. 

examining what takes place during 

of waiihiug. it is remarked, that the 

of ore, owing to the great hardness of the 

Bt the percussion of the stampers for a 

ble length of time, and that they only very 

ditnintflb in size (ill they are completely 

Tlie ore thus successively reduced into 

es, is gradually carried sway by the 

«ntcr beyond the labyrinth, where it 



ta 



ita 

itively 



ought to be deposited ; and the loss of this part of 
the ore i* more to be regretted, as the sulphuret of 
silver being very friable, it is the snlphnrct that \$ 
first carried away ; none remains but what i* con- 
tained in those pieces of the ore, which, from their 
size and weight, have had power to resist the in- 
fluence of the onrrent. 

I ara well assured that the loss which 1 have jost 
stated, is but too certain, as at the extremity of ■ 
labyrinth which readied for '200 roetrcs, 1 took up 
water that was impregnated with the dtposits of or*. 
This sediment, on being put to the test, yielded ia 
the lame weight« a proportion of silver equal to 
that of the sediment in the water at the entrance of 
the labyrinth. Tlie particles of gold disseminated 
in the aulphurets of lead, iron, and stiver, not in a 
BtJile of cnmhinntion, bnt only united mechanically, 
escape in the same way. 

Many ingenious men have tn their vritinga indi- 
cated as a method of collecting the gold contained 
in minerals and in auriferous sands, the levigation 
of these very finely comminuted substances ; but I 
cannot inppose that in this manner they imagine it 
poi^sible to obtain the whole of the gold ; this could 
only be done by means of chemical analysis. A 
very simple experiment will sulHce lo prove how 
very inefficient the levigation is for this purpose. 

Take two discs formed of an alloy composed of 
lead, silver, and gold, and girc them a circular 
motion against tbesnrfaces of each other, by keep- 
ing them immemed in a vciutel full of water. The 
water will very soon be rendered turbid and cloudy. 
If, in the same water, two discs of the mineral, in 
which the ores are imbedded (qusrti fur instance), 
are afterwards rubbed against each other, long 
enough to add new particles to those already con- 
tained in the fluid, all the metallic and earthy par- 
ttclrs will not be i>rttled lill after eight days, and 
no trace will be perceived on the outer aurfaoe of 
the glaas vase tbat the particles have been deposited 
according to their specific gravities. They will 
appear all mingled. Hence it mny be coucladed 
that when metals, ores, minerals, and sands in a state 
of extreme divihion are mixed, levigation is an ineflec- 
tual means of producing their complete separation. 

The next operation to be considered is that of 
EimcltinK the ores. The products of the mines are 
also greatly diminished at present by the loss of 
lead, silver, and gold, in the operation of smelting, in 
either reverberating or other furnaces generally used. 

In tlio former case the roasting of the slag ia a 
long and difficult operation, and with many ores 
almost impossible ; those of Baden for instance, of 
which the matrix composed of quartz, of sulphate 
of barytes, and of tluor spar, is fusible to such a 
degree, that in making use of the reverberating fur- 
nace it would be necessary to smelt without pre- 
viously roasting, and to let the first meliiog run oat, 
which it would be necessary aftewards to calcine 
before re-smelting in another furnace, which ma^t 
also be reiorted to, to extract part of the refractory 
scorise. The loases in smelting are occasioned — 

Ist, By the volatilisation of a great quantity of 
sulphuret of lead, and sulphuret of lilter, before 
their reduction. 

2d, By the action of the flaxes, and particnlarty 
by the silex on the lead at ita different degrees of 
oxydatiun, from whence is produced the siUciureta 
of lead which unite with the scoriir. 

3d, By the alkaline aolphureia and pcrsulphnrets, 
which, in a great degree, absorb the gold contained 
in the ore to be smelted. 



IdO 



MAGAZINE OP SCIENCE. 



4lh, By the great quantity of fael neceMary to 
be need to retain id a itAto of constant fluidity the 
enonnoui proportion of the KcoriN: of forges nod 
fumNCci obliged to be added to the melted ore, in 
order to secure the metal from being redaccd by 
^ oxydation aud Tolatilisation during the time it la 

rassing into and remaining in the furnace, where 
believe the Icmperatare ia raised to a much higher 
degree than is necessary. 

5th, Finally, because, inetesd of obtaining by 
one smelting in which there ii so great a consump. 
tion of eombnstible, the whole of the lead contained 
in the ore, only half of it ic at first extracted, and 
the other half most be afterwards calcined, which 
if only an impure metal or sulphuret, in order to be 
■melted again. 

I make no obserration on the manner in which 
the operation of cupelling it ia done at Baden, be- 
cause 1 beliere it is impossible to be managed better. 

The consequence of the inconveoiencea that 1 
bare ennmerated is, that though the prodnce arising 
from the gold and rilver lead mines is quite equal 
to what might be cipected in their present condi- 
tion, it is yet capable of being considerably increased 
by improving the method of washing and smelting. 
— A/oni/tKr indiutriet. 



SYSTEM OF EARTHENWARE PAVING. 

BY M. rOLONCBAU. 

NoTWiTiiBTAKDiNG the Improvements that have at 
various times been introduced in the method of 
paving, the roadways of our high roads and the 
atreets of our towna continue more or less uneven, 
which occiuions those frequent jolts which ore 
80 destructive to carriages and boraes. This state 
of the pavement is atlribatsble to many causes, the 
principal of which are the general formation of the 
paving stones, the wont of regularity in their 
forfaccfl. which does not admit of a good jiuta.jrosi- 
tion, aud the great difference in the hsrdnebs of 
the stuues, which, although taken From the same 
quarry, are aome of them worn out much sooner 
than others. This latter inconvenience exists not 
only with rejpect to the dilTerent kinds of slonc 
regularly made use of, but oUo, and in a greater 
degree, with respect to vegetable substances, so 
that the method of paving in wood, which has 
bcsen recently proposed, would, considered with 
reference to this, be inferior to stone pavement. 

So long ns stone pavementa are used, M. Polon- 
ceau Bays it will be impassible to adopt any difTe- 
rent form for the blocks than the one they have at 
present, which is that of a rectangular prism, for 
by substituting cutting for the ooramon method of 
breaking, the expense would be considerably in- 
creased, while at the same time the resistance of 
the stone would bo diminisbed in consequence of 
the repeated percuflsionB. 

The rectangular form ia attended with the in- 
convenience of Its bring neceaaary that half the 
joinings should be placed in the same direction ns 
the wheels, which are then compelled to follow 
them, and rub along the lateral ridges, enlarge 
the joinings, render the stones uf the pavement 
round, and considcrnbly increase the jolting. To 
remedy this incouvenitnce it has been attempted 
to plara the pavini; stones diagonally, but the aiij^jes 
being then struck obliquely by the wheuU the 
stones are broken and sink duwn yrt more rajndly 
than thry do in the usual method. Thus, in 
wbaterer muiner the paving stones may be ar- 



ranged, so long as they retain their rectmgaZar 
prismatic shape, (and they caunot oo an ecoDoai* 
cal principle receive any other, as it is effected by 
merely breaking them,} the pavement will from 
the first be rery uneven, and wiU beeone mon 
and morv so. It is in consequence of these coa- 
siderationa that M. Poloncesn haa been induced t» 
make ose of pavements of earthemntre, to which in 
the course of manufacturing, and without any ia- 
crease of expense, he gives the form likely to be tb« 
most durable. By means of plastic clay uoited 
with sands and cements, and pnlTerised charcoal. 
be Bucoceded in obtaiuiug pieces of earthenwar* of 
considerable strength and sise, which could bt 
well dried withoot breaking, and bear exposure to 
a very great d^ree of tieat without becoming 
vitrified or altered in shspe. These pieeea of 
earthenware are unpolished, and will strike Ar» 
with steel, resist blows as well as common parittg 
stones, and are much less impermeable to moisture. 

The pavements formed with this eompodttos 
are six-sided prisms in the hexagonal form ; tke 
joinings are all either perpendicular or r>bUqna ta 
the motion of the wheels, and this withoot beia( 
subject to the inconvenience arising from having 
the paving stones placed diagonally ; because tkt 
angles of the hexagon are stronger Chao thoM tt 
the rectangle ; and tliis advantage has be«n eo«> 
sidrrably augmented by reducing the sides of the 
prism by cutting a number of small ridges fron 
three to four centimetres in site. 

The only object in thus Bubdividing the turfaett 
of the blocks is to obtain more obtuse angles ; bet 
the triangular space which is the conieqaence of II 
is also useful as a receptacle for the bitumen 
with which these paving stones are cemented 
together. 

Each paving block is perforated through the 
centre with a vertical bole, and on the outside than 
ia a groove in which the bitumen lodges, which, by 
tills means, is more cfiectusl in rendering Uio 
different paving stones more firmly united, and is 
jirevrnting them from sinking, la order to readtf 
this method of cementiitg more easy, the outaidd 
of the paving blocks are cemented when theysrt 
taken out of the furnace, and before Uicy are 

Great exactness of form can be readily gi 
the cartfaetiwarc blocks. Tliey are easily 
together, and their joinings are so very dose 
tlie wheels can never be locked in them. Notwilh- 
stand'mg this absence of furrows, the cermnqm 
pavement, as It is called by the inventor, is 
adapted to horses, as the surface never 
slippery. As it does not become round at the 
there is much less liability to slip; beaidee: 
holes in the centre of the pavement, and the 
gular cavities at the edges being tilled with 
mixed with bitumen, they form so many rcsti 
the horses' feet. 

The firmness of these pavements, M. Poloa- 
ceau remarks, has given rise to one objection. 
It has been appreheuded thai it would be rilnrmdy 
difiicult to make openings for the gas and wsttf 
pipes; but the difficulty would be avoided by filKaS 
the vertical holes in Uie centre of tlie pavrnrat 
with gravel without bitumen ; it would hf evf« 
quite sufficient if this precaution were onI^ 
at one of the two rows platred abore ■- 
because the communicatiun with the exteri'T ••i-<;'» 
then be quite as easy as it is in the usual mrthsd 
of penng.— /n«iifor«' Advoc^t. 



MAGAZINE OF SCIENCE. 



ISl 



IRDANTS FOR DYEING. 

liDordant, in dyeing and ctlico-prmtin^, 
kodj which, having a twa-fold attrticdon 
I fibres ind coloring pnrticlcK. Mrves ■■ a 
^ioD betwren them, and thuR give* ftxilj 
|r it signitiei a vubstance which, by com- 
b coloriog particles in the pores of textile 
^Dden them inioluble in hot ^apy and 
^ne Bolulioni. In order properly to ap- 
|e atilitj and the true functions of tnnr- 
biuit bear in mind that coloring matters 
t compounds poaaessed of certain adiuilira, 
iclivc charncieri being Dot to be either 
ftUioe. and yet to be capable of comhiniug 
r bodies, and especlUIy with skllliable 
(of receiving from each of ihem mndifi- 

L their color, solubility, and altenibilily. 
loriDg subfctonces. when pure, have a 
fetic attraction for certain bodien, feeble 
land none at all for sonic. Among these 
tproductB of animal or vegetable life, sorofi 
p in pure water, and others become so 
~;h pecoiiar agents. We may thtu readily 
lat whenever a dye-stuff poasessrs a cer- 
for the organic fibre, it will be able to 
gd on it, or to d^re it without the inter- 
Imordanla, if it be insoluble by itself in 
kb, in faot, is the case with the coloring 
ifflower, annottOf and indigo. The first 
liable in alkalis ; hence, in order to use 
j need only be dissolved in a weak alka- 
I thus applied to the stuffia, and then have 
prial substance precipitated within their 
■bstracttng their solvent alkali with .m 
[coloring matter, at the instant of ceasing 
A, is in an eitremely divided state, and 
Btwith the organic fibres for which it has 
jBinity. It< tbcfofore, unites with them, 
^ naturally insoluble in water, that is, 
I affinity for this vehicle, the sabsequent 
Mie no nflect upon the dye. The ssme 
p9 said of indigo, although its solubility 
■bath does not depend upon a similar 
dae to a modification of its constituent 
consequence of which it becomes sulu- 
Stu0s plunged into this indigo bath 
ited with the solution, so that wbca 
to the air, tlie dyeing subRtnnre re- 
its primitive color and solubility, and 
carry off only the portions in excess 
f, intimate combination, or which are 
iDsited upon the surface of the stuff, 
phe result with insoluble coloring matters; 
be which ore soluble it should be quite 
L since they do not possess an affinity fur 
m fibres which can counterbalance their 
prater. In such circumstances, the dyer 
I recourse to intermediate bodies, which 
Ufinity for the coloring matter to that 
p7 the particles of the stuff, and increase 

tfold action the intimacy and the stubility 
ioation. These intermediate bodies are 
hrdant*. 

\m are in general found among the me- 
I or oiydes ; whence they migbt be sup- 
I rery nameroas, like the metals ; but as 
^ntle the two-fold condition of possessing 
UBnity for both the coloring matter and 
b fibre, and as the insoluble bases are 
lonJy ones fit to form ins^olnblc cumbiiia* 
My that perceive that their number may 



bo very limited. It is well known, that although 
lime and magneaia, for eiamplftf have a conuder- 
oble affinity for coloring particles, and form intoln- 
ble compounda with them, yet they cannot be em* 
ployed B8 mordants, because they possess no affinity 
for th« textile fibres. 

Experience has proTed, that of all the bases, 
those which succeed best as mordants are alaminSp 
tin, and ozyde of iron ; the first two nf which, be* 
ing nataralty white, are the only ones which can be 
employed for preserving to the color its originid 
tint, at least without much variation. But when- 
ever the mordant is itself colored, it will cause the 
dye to take a compound color quite different firoa 
its own. If. as is usually sold, the mordant entera 
into a renl chemical union with the stuff to be dyeilf 
the application of the mordant should obviously be 
made in such circumstances as are known to be 
most favorable to the combination taking place ; — 
and this Is the principle of every day's practice in 
the dye-house. 

In order that a combination may result between 
two bodies, they must not only be in contact, but 
they must be reduced to their ultimate molecules. 
The mordants that are to be united with staffs are, 
as we hare seen, insoluble of themselves, for which 
reason tlieir particles must be divided by solution 
in an appropriate vehicle-. Now this solvent or 
menstmnm will exert in its own favor on affinity 
for the mordant, which will prove to that extent an 
obstacle to Its attraction for the stuff. Henee we 
must select such solvents as have a weaker affinity 
for the mordants than the mordants have for the 
etnfffl. Of all the adds which can be employed to 
dissolve alumina, for example, vinegar is the one 
which will retain it with least energy, for which 
reason the acetate of alumina is now generally sub- 
stituted for alum, because the acetic acid gives up 
the alumina with such readiness, that more eleva- 
tion of temperature is sufficient to effect the separa- 
tion of these two substances. Before this subslitu- 
tinn of the acetate, alum alone was employed ; but 
without knowing the true reason, all the French 
dyers preferred the alum of Rome, simply regarding 
it to be the purest ; it is only within these few years 
that they have understood the real grounds of this 
preference. This alum has not, in fact, the some 
composition as the alums of Prance, England, and 
Oermany, bntit consists chiefly of cubic alum hav- 
ing a larger projiortion of bue. Now this extrB 
portion of base is held by the sulplitmc acid more 
feebly than the rest, and hence is more readily de- 
tached in the form of a mordant. Nay, when a 
solution of cubic alum is heated, this redundant 
alumina falls down in the state of a subsulphatv, 
Inng before it reaches Ibe boiling point. This dif- 
ference had not, however, been recognized, becsuae 
Roman alum, being usually soiled with ochre on the 
surface, gives a turbid solution, whereby the preci- 
pitate of subsulphate of alumina escaped observa- 
tion. When the liquid was filtered, and crystal- 
lized afresh, common octahedral alum alone waa ob- 
tained ; wbrnce it was most erroneously conelnded, 
that the preference given to Roman alum wss nn- 
justifiahlc, and that its only superiority was in being 
freer from iron. 

The two principal conditions, namely, extreme 
tenuity of particles, and liberty of action, being 
found in a mordant, its operation is certain. Uut 
as the combination to be effected is merely the re- 
sult of a play of affinity between the solvent and the 
atuff to be dyed, a tort of partition mutt take place, 



I 




MAGAZINE OF SCIENCE. 



to the D»n of tbe lolwDt, u well u 
•ttTictiTc force. Hence the ituffwiU retain 
of the tnorduit wUen it« solotion i« more cou- 
oetttnfinl, (hAl Is. ffbea tbe but diffused tbroagh 
h t* b9< to toodi protected bjr ■ Urge mass of men- 
Mmm : a fact a(fptied to very rsliuble uses bj tbe 
pimlkjd «Mti. On impregnstinK ia o«lico printing, 
br ctaapfe, different spots of the same «reb with 
ttM mM mordwit in difTerent degrees of concentra- 
lio«« then is obulaed in the dve-batb a depth of 
O ttht bfKra these ipotj intense in proportion to the 
itRiifA of tbdr various mordants. Thns, with 
of acetate of alumina in different gradei of 
r, «ad with madder, every shade can be pru- 
from the fullest red to tbe lightest pink ; — 
l» with acetate of iron and madder, ererjr ibade 
black to paJe riolet. 



I 



INEXPLICABLE PHENOMENA OP 
UNiVNl^EALED GLASS. 






Vi% bare long been accustomed to regard the 
pbenomeaa which precede and attend the fracture 
of unanoealed glass* <u some of tbe most remark- 
able and ineJiplicable of all the manifold secrets of 
■stun. Many other phenomena, although curious, 
mixbt have been predicated after mature reflecdont 
as they are in strict accordance with the known 
Isws of nature ; but we think wc may confidently 
assert, that no mnn, hovr skilled soever be might 
be in chcmiBtry. or any other department of natural 

fBhilosopbjr, could tutTe predicted the effect pro- 
Sucfil upon onannealed glass by the most appa. 
fently iniigniAcant and inadequate cause, U any 

Ipbilosopher or chemist, for instance, had been 
Asked what would be the consequence of dropping 
ft few grains of light &aii<l into a goblet of gUsn uul 
properly annealed, he would nerer have guessed 
that the effect would be to shiTer the tumbler into 
AtomR* As it is possible that some of our readers 
nay not understand what ia precisely meant by 

»iinanoealcd glass, it msy be proper here briefly to 
u plain the term. 
Wban s'"'*' from the melting-pot, is [fashioned 
IbIo tumblers, bottles, &c., it ii gradually cooled by 
batng remoTod successively from ■ higher to a 
lowtf temperature, which process is termed anneal- 
ing. WUen this gradual process is neglected, tbe 
iBOst extraordinary results are found to take place. 
^"Wbat are called Pnnce Rupert's drops are an ex- 
silent and familiar illustration of tbe anomalous 
jheDomena under conaideration. They are formed 
limply by dropping a little melted glass into cold 
Lwatrr, when it Huddenly collapses into a small 
rpear-tibaped drop, with a slender tbread-likc tail 
)r extremity. If the thick end of the drop be held 
the bond, and tbe small end be broken off, the 
rbole of the glass will fly into shivers, imparting to 
hand a imsri shock, similar to that from an 
Iglaotricol jar. What is equally singular is, that if 
Knpftrt's drops, instead of being broken in the 
manner deicribed, be thrown down forcibly upon 
Hags, they will recoil by their elasticity, but they 
rill not be broken, bow violently soever they b« 
)ught into contact with the tiaga. 
We have now to ootice another of tbe numerooa 
idmena exhibited by unannealed glaas, which 
not no generally known as that of the Rupert's 
rop* but which is equnlly inexplicable. It was 
ifDinanicoted to us several months ago, by tbe 
mdeot whose note we herv subjoini with « 




few comments appended to it :~ 

" Sir. — Allow me, then, to detail a mrious 
accident which happened under my own hands, 
with a glass tube, and which has occurred to srvtfol 
others, tu whom I have meutioned it. Some ihort 
time ftgo I procured a gloss tube for the purpose of 
constructing a barometer. After cleaning it weti 
with an iron wim, tipped with wash leather, I 
placed it upon o t^ble, and was astonished to 
in a quarter uf an hour, the tube bruken into »evi 
pieces. On mentioning it to a friend he immedial 
pronounced it to be caused by tbe wire, as he 
had a similar accident. Not being salifthed 
could be produced by tbe wire, I placrd 
tube witb a bit of wire in it, and was 
find, that, in a short time, the tube brol 
several pieces. I cannot account for the phenomi 
neither is the fact noticed in any «cienti5c 
with which 1 am acquainted. Barometer 
seem to be aware of it, and ne>Tr use wire in : 
ing ibcir tubes." 

The phenomenon, which is the subjoct of 
correspondent's letter, is familiar to the baroi 
makers, who, in cleaning oat the interior of 
tubes, take especial care that the iron wire 
ployed for the purpose shall not touch the gloas, 
the contact of the two substances is olmost 
formly followed by a fracture of the glass, 
immediately, but after a short interval. This 
one of the moit extraordinary drcomstauces of th* 
phenomenon ; as it is difficnlt, if not impossible-, ta 
form any rational explanation uf the secret mrstC' 
riona operation which must be going on in tbe tube, 
between the moment of contact with the vire 
the subsequent fracture. If, as there is ream 
conclude, the momentary contact of the wire 
the glass produce the fracture, why does it 
instantly take place.' There sppears to be 
effect, without an adequate or intelligible e 
It seems that this kind of phenomenon is not 
gether eonfined to glass, but ocoasiouolly ocoml 
cast metal, probably from Its sadden cooliag, 
from not having bMii properly inneoled. 
ever that may be. it is a fact that the modi 
which the mirrors of reflecting teleseopea 
stmcted, is very apt to fly to pieces by the 
scratch, just like the borometer tubes, in 
quence of their coming in contact with tbe iron 
used to clean out the inside. 

In conclnvion, we may observe, that the 
nomenon of the barometer tubes, noticed by 
correspondent, is to be ascribed, no 'doubt, to 
imperfect annealing; and that the remedy for i 
defect would be that pointed out by Mr. Pelli 
of Ix)ndon , at a late scientilic meeting, 
the report of which we transcribe the folic 
passage : — 

" Mr, Pcllatt recommended boiling as a safe 
good mode of annealing all kinds of gloss, li 
ordinary method of annealing, thick and thin 
is often subjected to the some proceas, and rei 
in tbe leer fur the same period ; this would i 
for the superior duration of the thin tidies, 
attributed Uie ^ctnre of the tubes to tbe teottei) 
the exterior coating and the vibration caused 
the process of cleaning ; this effect «u ao 
knowu that an old tube could scu-cely be 
01 it generally broke in ctcaning." — i 
Mercury. 



MAGAZINE OF SCIENCE. 



16S 



IGNATION OF WATER WITH 
OXYGEN. 

^iogenioiu bnt laborioca plun of efTecling 
jtes purpoM is related by M. Thenard in 
bh rolQnie of the Annattf 'tie Chimie ei 
mke : from thencp the dplatl of the ne- 
perimenta was translated into the Engliah 

follows r — 

prepanilion of oxygenated vnter requires 

icaatlons, without which aucceas will 

rtial. Tliat none may bo omitted, 1 

Ribe the process in the most minute 

te of b«r7tei ahoulil first be obtained 

re, and abore nil, frfe from iron and 
The moat certain meana of procuring 
toUc the nitrate in vrater, to add to the 
amall exceaa of barytea water, to filter 
ftUtse. 

pure nitrate is to he decomposed by 

on^ht not to be done in a common 

retort, because it contains too much 

ides of iron and manfsoeac, bat in a per- 

B poroelatn retort. Four or (ire pounds 

of barytea mar ^^ deromposed at once, 

wilt require about three hoars. 

thus obtnioed, will contain a con- 

joantity of silex and alumine, bat it will 

Tvry minute traces of maoganeae and 

enmstaoce of essential importance. 

B buytes. divided by a knife into pieces 

the end of the thumb, should then be 

k luted tube of glass. This tube should 

id Urige enoufh to contain from 2 lbs. to 

ia to be surrounded with fire, and heated 

heas, and then a current of dry oxygen 

te passed through it. However rapid the 

the gaa is completely absorbed ; so that 

by the small tube which ouf^ht to 

the larger one, it may be concluded that 

Kydeof barium is formed. It is. however, 

Detinue the current for seven or eight 

re. Then the tube being nearly cold, 

kyde, which ia of a light grey color, is 

and preserred in atoppcrcd bottles. 

certain qaandty of frater, for exsmple, 

, ia then taken ; to which is addt^d aa 

) and fuming hydrochloric arid aa will 

DO grains of barytes. The add solution 

ft glass with a foot, and ice placed round 

nnut be renewed as it melts. Then 

of the deutoxyde are to be very slightly 

t and nibbed by portions in a mortar of 

AS*. As these portions arc reduced into 

S, they are lo be r^imored by a box-wood 

placed in the fluid ; they will soon dis- 

lonl efferrescrnce, especially if slightly 

Wheo the solution is made, pare and 

ted sulphuric actd is added, drop by drop, 

Nang stirred at the time with a glass rod, 

b a alight excess of it, which is easily 

Che property possrsaed by the sulphate of 

«t the moment, of readily depositing 

; then, aa at first, a fresh quantity of 

ii diuoWed in the fluid, which Is again 

d by snlpUuric acid. The deuCoxydc is 

ly to diatinguiah from the sulphate. It 

It to add enough sulphuric add to pre- 

i the barytea, but not too marh. If 

sot added, the fluid filters with difficulty, 

if too nacb U added, the flUratiun 



also goes on badly. On arhving at the exact point 
mentioned, the filtration takes place with the 
utmost farility. When the filtration ia completed, 
a small quBDtity,.of common water is to be passed 
through the filter, and added to the first fluid ; In 
this way the tatter does not lose in volumn: then, 
tbut nothing may be lost, it is nec«asary to spread 
the filter on n glais plate, to separate the sobstance 
from it, diffuse it through a small quantity of fresh 
water, and filter it. The water thus obtained ia 
but slightly charged, but it is uaefol to voah the 
future filters. 

"This opcfBtlon being finished, flnothcr Is made 
exactly similar to it, i.'e. deutoxyde of barium is to 
be dissolved in the fluid ; the barytcs is to he pre- 
cipilatcd by sulphuric acid, and ao on ; and the 
fluid is not to be filtered until after two solutions 
and two precipitations. It is^on this new filter 
that the water obtained by washing the prcdpltftCe 
in the preceding operation ia to be poured ; after 
which fresh weak water is procured by waahing the 
matter on the last filter. 

"The second operation is followed by a tliird, 
that by a fourth, and thus, until the fluid ia iiuRi. 
ciently charged with oxygen. By using the quan- 
tity of hydro-chloric acid mentioned, 30 ounces of 
deutoxyde of barium may be operated on, and a 
fluid will be obtained charged with 25 or 30 timea 
its volumn of oxygen. If it is required to be 
further oxygenized, more hydro-chloric add must 
be added. 

" I have many times succeeded by this means in 
charging the fluid with 125 timea ita vnlnmn of 
oxygen, but I added add enoogh to dissolve -463 
grains of the deutoxyde, being careful also to pre- 
serve the acidity such, that st the end of tho 
operation 1 could dissolve about 30'J grains of tho 
deutoxyde, without the aid of sulphuric at^id ; but 
I have ascertained that when the tlnid contains 
nearly 50 volumns of oxygen, it nllows so much gaa 
to escape from one day to the next, that there is do 
advantage in continuing to oxygenate it by the 
deutoxyde. 

"5. When the fluid is oxygenated up to the 
required point, it is to be ssturated with deutoxyde, 
retaining it at the same time in ice. Abundant 
flocculi of silcx and alumine soon separate from it, 
which are generally colored yellowish- bro«rn, by a 
little of the oxydes of iron and manganese. The 
wholR should then be thrown quickly on a cloth, 
ittclosed in it, and strongly compressed. Thia 
operation cannot be done well except by two persons, 
and shonld bo performed rapidly; for though there 
is bat a very minute quantity of oxyde of manga- 
np.«e, it is suffident to produce a considerable dis- 
engagement of oxygen. 

"6. As the fluid which has paosed the cloth 
may still retain a small quantity of silcx, iron, and 
manganese, and as it is necessary to wparate all 
these substances, it is again to be surrounded bj 
ice, and barytea water added to it, drop by drop, 
the whole being stirred. If, when the barytcs is 
in such excess as to be slightly sensible to c<florcd 
paper, there is no precipitate, it proves that all the 
oxyde of iron and manganese are separated ; if 
tbey have not been completely separated in the 
preceding operation they will by this. 

f TV &e Wfi<M«#d.J 



' >^^^'^w^^^^^^^^<N^ 



184 



MAGA2INE OF SCIENCE. 



MEDICAL RECEIPTS, &c, 

Onutonian Embrocatioii. — Take l} ounce each 
of olive oil and oil of turpentine, 3 oancea of dilutti 
sulphurio acid ; mix, aud apply to the aurbce of 
rheumatic joints, &c. 

Grty Lotion is prepared by addlog Tariable pro- 
portions, according to the case, of chloride ui mcr- 
cury to lime water. Used for aoothing irritable 
aorea. 

HATTinegate Water^ imitated by dissolnng 5 
grainB of Bulphnret of potaaa in a glasa of soft water. 

Heading Jhr Bter. — It is not known well upon 
what principle, bat the fact iacertaio, that Bulphate 
of iron (Orent CopperoM) added to beer makes it 
carry a head, or froth, though It be weak. The 
stuff, sold under the name of heading, consists of a 
mixture of alum and sulphate of iron. 

Henry't Aromatic Vineffar is an acetic solution 
of camphor, and of oil of cloves, lavender, and rose- 
mary. Imitated by putting 1 dram of acetate of 
potass into a phial with a few drops of any fragrant 
oil and 20 drops of sulphuric add. 

Hippocras ia prepared by macerating for seven 
days 6 pints each of Madeira and Canary, with 1 
ounce of cinnamon, 2 drams of canella, and ) dram 
each of cloves, nutmeg, mace, ginger, and carda- 
moms. Strain and odd ( ]iound of refined sugar. 

Honey IVator. — la prepared with 1 gallon of 
Cognac brandy, 1 pound each of virgin honey and 
coriander seeds, 1| ounce of cloves, I ounce each of 
nutmegs, benzoin, and storax, four vaniUoes, and 
the rind of three large lemons. Digest for two 
days, and dislU with a gentle heat. Add to every 
gallon of the water, thus procured, a pint and a 
half each of orange*flower water, and rose water, 
and 5 groins each of musk and ambergris. Digest 
again for thrive days in a gentle heat; Alter and 
keep to a well-stopped bottle. Several other re- 
ceipts are in use, but they do not differ much from 
Ibis. Imitated by mixing fragrant esscaca, color- 
ing them with saifron, and thickening them with 
honey ; or take 2 pounds each of rose water and of 
orange-flower water, ^ ounce of oil of cloves, 2 
oancea of essence of bergamot, ^ ounce of oil of 
lavender, 16 groins of musk, 1 gallon of spirita of 
vine, ond color with saffron. 

Hooper' » Pillt. — Take 1^ pound of aloes, 2 
ounces of myrrh, ^ pound each of carbonate of iron 
and of sulphate of iron, add also a little canella 
bark and ivory-black. Make into ■ mius, and di- 
vide into four 'grain pills. 

Huilfj Antiques arc chiefly composed of oil of 
ben, or oil of haiel, which having no smell of its 
own is ready to Imbibe any other odour with which 
it may be combined. They are often, howercr, 
made with olive oil. 

HmHc Antique a t' Orange. — With 1 pound of oil 
of ben, mix 'S ounces of essential oil of orange, and 
put it into small bottles, well corked, with wax over 
them to pretserve it from the air, and prevent the 
perfume of the orange oil from evaporating. 

Unite Anttyue h ia Rote. — Procure a tin, or white 
iron box, about a foot iqiiare, opening by a grating 
on one side, and divided in the middle by a parti- 
tion of white iron, drilled full of small holes, close 
to each other. Fold in four a cotton towel, soak it 
in oil of ben, and place it on the grating so si to 
eiactly fit the box. Upon this cloth place rose- 
leaves, fresh gathered, leave them for aboat 24 



hours, and then replace them with frrah 
The cloth may then be removed, and (h«i 
charged with the perfume, carefnily ejpraM 
This may be mixed with fre«h oil of ben, 
for use. 

In the fame manner may be made 
tiquet a la Fleur d" Orange, a la Vtotette, 
qville, au Jatmin, &fc., and by roeana of r 
mixtures — a V Heliotrope, mtx MUte FUm 
Pot-pourri, &fe. 

Huite Antique a ta Tuberoie. — Mix the t 
with ground blanched bitter almonds, and thi 
press the oil ; or mix a pint of olive or almoi 
with 30 drops of the essence of tuberose ilowei 
this way also several of the above Huiiea An 
can be prepared. 

Iringlaga Mucilage.— A vehicle for water C 
invented by Mr. Robertson, of Worton Lodgi 
is pre|iared by macerating shreds of good! laii 
in water till thoroughly soft, dissolving thi 
boiling alcohol, so that a compound duid b< 
duccd when cold. It gives water-color pali 
great power and permanence. 

James' M Analeptic PilU. — The original recei 
Take 1 dram each of James's powder, Rofiis' 
mass, and gum guaiac ; make a maai with tb 
of castor, and divide into 40 pills. Tliey ara a 
made, however, with compound antimonial po 
instead of James's powder. 

/ames's Powder. — This celebrated nostnia 
analysed by Dr. G. Pearson, and found to n 
!t7 parts of oxide of antimony, partly vitrified 
43 parts of phosphate of time. Mr. R. PhiUif 
lately found the proportions of these to be 5 
44. The original specification of James is: — " 
antimooy, ralcioe it with a continued proti 
heat, in a flat unglaxed vessel, adding to it 
time to time a volhcient quantity of any aoim 
or salt, depUegmated ; then boil it in melted 
for a considerable time, ond separate the p< 
from the nitre by dissolving it in water." 
however, is a faUe receipt, as it will not pn 
the powder. That there is a regular and et 
process for its preparation, is proved by the 
larity of the two analyses by Pearson and Pi 
at B considtrablo distance of time. 

Jewitit's Drops arc compound tincture of be> 
or compound tincture of copaiba, mode with 1 1 
of gum guaiac, 2 ounces of copaiba, 2 draau 
of laasafras, aud \ pint of alcohol. 

Kermet Mineral, an aatimDni.il mcdidnf d 
great repute on the Continent. It is prepar 
bailing for an hoar one port of carbonate of pi 
with four pnrta of native sesqul-aulphnret of 
mony finely pulverised in a quantity of 
ing and setting the liquor aside to cool, 
tate of which is the kerracs. 

Keyeer'a Pillt, Drage$ de Keyeer. — A 
nostrum composed of acetate of mercury and n 
and reputed to be auli syphilitic. 

iSTnor's Dinnfectimj Powder. — Mix eight 
of chlorinated soda with three parts of chloii 
lime. An ounce of this dissolvtd in a tuob 
water is similar to Ijabarreque'-t liquid. 

Lardner'n Prepared Charcoal. — Tril 
with charcoal or ivory black. 

Lignvrn's Antixcorbutic Drop* consist 
guiscd preparation of bichloride of mercury, 
proprietor's name was originally Ifbotf, itld 
thought it advantogeous to translate into Latii 



itai^ 
1st sF 



Lownon.— Prlalcd by O. KaAKcii, 6. Whit« Hon* Latw. Milt End— PubllOied by W. BHirtAiN, II. PaCSrMstn Ifa 
Conranolcalioiu. (<*hkh ate auwtrtd Uontbly.) t« be a(ldreM«4 lo th« Edttvr, at 27. ColUc* Gt9v*. Mil* T " 




THE 



AGAZINE OF SCIENCE, 

^nO ^cjbool of ^rtg. 

SATUKDAY, SEPTEUBEB U. 1841. 




HYDRAULIC MACHINES. 



lU.— NO. XXIV. 



ISG 



MAGAZINE OF SCIENCE. 



HYDRAULIC MACHINES. 

Wb give iUustrationa upon the present occasion of 
two or three littlo known, yet rery valuable bj- 
draallc instraments ; one of tfaem, namely, the rope 
pamp, hafl been kooirn for a very long period, and, 
after remaining too long disregarded, has been lately 
rc-invented or rc-inlrudnced under the name of 
Hall's hydraulic bell — we give cngraviiigf of both, 
that they may be compared. The hydraulic belt 
(No. 1,) is, with the exception of the pipe that 
conveys away the water raised, the repreacntation 
of that exhibited at the Polytechnic Institution, 
London; the other (No. 2,) u from Walker's 
<* ElemenU of Natural Philosophy." 

The rope puvtp is an instrument for raising water 
by mesns of a loosely'Spun rope, which dips into 
the water of the well, and being put into a rspid 
motion, the water, adherent to the rope, acquires a 
certain momentum — that is, a force or power of 
continuing itacU in motion, notwithstanding the ef- 
fect of gravitation, which acts in drawing it down 
again ; or in other words, it acquires, in consequcDce 
of the very rapid motion of the rope, a very con- 
siderable centrifugal force^ so » to overcome the 
aDtagonisl force, the centripetal, or the tendency 
to fidl downwartli. This centrifugal force or mo- 
mentum will continually increase according as the 
water rises, because the force it continually receives 
from the motion of the rope is not lost, but on the 
contrary, as soon as it exceeds the centripetal force, 
which is as soon sa the water mes at all, the ex- 
cess of the two forces is continually accumulating, 
and forming a momentum, which carries the water 
onwardi. So evidently is this the case, that when 
the water arrives at the cistern above the upper 
end of the rope, its direction being suddenly changed, 
the water flows upwards and forwards with con- 
siderable force. Taking this, then, 88 an explana- 
tion of the mode of action of this and similar ma* 
chines, it may be thought that water may be carried 
to any height; this is not exactly the case, for two 
reasons — one is, the power required increasing aa 
the weight of the whole body of water iaereasei, 
and thst rooltiptied by the height it is to be raised ; 
and secondly, from the circumstance that there are 
always particles of the fluid being detached from 
the column of water, and these, when no longer 
partaking of the impulse continually given by the 
ropo, soon lose whatever momentum they may have 
acquired, and fall again into the reservoir at the 
bottom. With this last cause of failure constantly 
occurring, aifd a recollection that there is no chain 
of backets or paternoster work to aaaist in raising 
the water, it is astonishing whst a vast quantity 
may be raisrd to a considrrable height, and with 
the expenditure of very little power. The struc- 
ture of the rope pump is so simple that to see a 
figure of it is tantamount to understanding it -, it is 
repmented in Fig. 2, where the letter A ihowi the 
ropfl raising the water from tbe well. It passes at 
the lower end under a spindle or axis, and at the 
upper end over a similar axis B, forming an endless 
rope, the two ends being spliced togetlier. The 
upper axis has a pulley attached, over which passes 
•nother endless rope C, leading to the large wheel 
below. As soon aa a person turns the large wheel 
by tbe winch attached to it, he, of course, puts not 
merely its own cord in motion, but also tbe rest of 
the moveable parts of the machine, the water rope 
and its two aies ; supposing, therefore, that the 
lower oo« dips into the water of tbe well, it will be 



raised, owing to the caoses we have 
plained, and flow into the cistern above, wfaa 
may be conveyed at required. The reason 
does not descend again with the rope is th 
latter, pasaing upwards > has to go through n 
bole in the cistern, that the water may not 
peded in its ascent, but as soon u it lama o 
passes through a pipe only large enough to 
the rope itself, therefore the water not I 
thrown off by centrifugal force, is, as it were, • 
from tbe rope, and falliog into the cisterD 
carried away. 

The patent kydrautie beii, or water deti 
Mr. lUU. differs in no respect in principle fri 
above, the differmce conslsUng in tbe sobst 
of a wide belt instead of a rope ; it thereby ia « 
to raise a larger quantity of water witMn i 
time. In the cut No. 1, A is tbe hydranlic I 
the roller, over which the belt revolves ; C tl 
torn roller, under the surface of tbe water ; C 
discharged on passing over the roller ; E al 
receive the water raised ; P wheel by whi 
whole is pot in motion. 

The other figure (3) is not given as a repn 
ItOD of any machine similar in structure to ei 
the above, but as one of a pump as little knon 
whkbhaabeenas much neglected as the rope 
although one which is very effective in ni 
large quantity uf water to small heights, and 
like the others, may be made by any car] 
without the assistance of the plumber or 
maker. A B C D, Fig. 3, is a square tr 
carpenter's work, open at both ends, and hs 
little cistern and spout at top. We have a 
presented it as with a long pipe at bottom, b 
is not always necessary. Near the bottom 
square trunk is a partition of wood, perfbrabi 
a pole E, and covered with a commoa did 
or dock OS it is called. Above this is a long 
drtcol bag made of leather or of double canTM 
a fold of thin leather, such as sheep-akin, betwt 
canvaxs bags. This is (irmly nailed to the be 
with soft leather between. "The upper end of t' 
ii fixed on a roand board having a hole and 
IliiB board may be turned in tbe lathe with a 
round its edge, and the hag fastened to it by 
bound tight round it. The fork of the pist 
F G is firmly fixed into this board ; the bsg I 
diatcnded by a number of wooden hoops or t 
strong wire, put into it at a few iochea dl 
from each other. It will be proper to c 
these hoops, before putting them in, by tl 
four cords from top to bottom, wbich will 
them at their proper diatancea. Thus vrill t 
have the form of a barber's powder-puff*. 
distance between the hoops should be aboa 
th(^ breadth of the rim of the wooden ring to 
the upper valve and piston-rod are fixed. 

Now let this trunk be immersed in tbe 
It is eWdent that if the bag be ttrctched fr< 
compressed form which its own weight wil 
it by drawing up the piston-rod, its capaeJ 
be enlarged, the ralve E will be shut by ii 
weight, the air in the bag will be rmrefied, a 
atmosphere will prcsa the water into tlu 
When the rod is thrust down again, this wat 
come out by the valve E, and fill part of tbe 
A repetition of the operation will have a i 
effect ; the trunk will be filled, and tbe wat 
at last be discharged by the spoQL 

Here is a pomp almost divested of fricUo 
perfectly light ; for the leather between tliQ 



WA 




MAGAZINE OF SCIENCB. 



W 



rtoAtn the bag inperrioiu both to air 
( aod the canvnii has very couniiierable 

We knoir, from eiperifnc*. thnt a ba^ 
kea diaraecer. mad« of tail-cloth. No. 3, 
tp-ikin between, will bear a ^oliimn of 

of water, and six hours work per tlaj 
h wtlboat failure, and that the pump ia 
\j superior in efTert to a common pump 
B Aowmions. We mast only observe, 
|ig^ of the bag must be three limn the 
inftb of the stroke ; so that when the 
U in iu highest position, the angles or 
be baf may be prettr acute. If the bai^ 
retched than this, the force which must 

by the laborer btHninies much greater 
fright of the column of water which he 

If the pump be laid aslope, which is 
in then occasioaal aod hasty drawings, 
^ to make a guide for the piston-rod 

tninkt that the bag may play up and 
tnit rubbing on the sides, which would 
fcr it oat. 



iND DELCAMBRE'S COMPOSING 
MACHINE. 

» arc at all acquainted with the printing 
ad know that erery letter of every word 
e piece of metal, and must be taken up 
by the compositor, then turned the r«ce 
bd the proper part of the letter to the 
page. wUl scarcely belieTc it possible that 
pould be constructed, which will of itself 
■11 this, and with facility — yet such an 
la operatioa, and may be seen at 110, 
MBe, London. We refrain from giving 
of its coastrnctiOD, because the iogeoiouB 
fopOfM some great improvements in and 

ri of tome of the parts ; and until these 
we should necessarily have to describe 
ct instrument than we hope KtiorM j to be 
Introduce ; from drawings and description 
tve kindly been promised by Mr. Young, 
IT. The principle upon which the roa- 
we may, however, as well state. It is 
re are a number of loog troughs put in 
rtical position, one for each kiud of letter 
meter. These are filled with the type 
{ at the bottom of each is a stud or key, 
haraeter of the letter upon it, ABC, 
Upon pressing down this stud, a letter 
ttt of the trongh attached to it. It slides 
ficUned plane, and deposits itself hori- 
I a long groove prepared to receive it. 
t% succeed, according to the keys which 
I ttpoo, and rest upon the former, until a 
lera is formed, 2 feet or more in length. 
of letters is taken away, and ■ second 
(ititoted and 61Ied as at first. The long 
tn taken away is justified ; that is, made 
DCS of a certain rec^uired length by a 
ton. Mr. Young calculates, that 14 or 
ten may thus he set up in an hour, and 
with the requisite attendance, will cost 
per thousand, or about a quarter of the 
Ai^e. For newspaper work, and other 
rapid printing, the machine appears well 
It is extremely simple, not liable to be 
tr, occupies but little space, and as to 
be coosidered imperishable. 




POTABLE GOLD. 

Ir tliere be no reason to think that gold will ever 
he made, is it not possible to employ this precious 
metal for prolonging life ? Gold is a metal unalter- 
able, and as difficult to be destroyed as to be made; 
it ii the sovereign of the roetAllic world, as the sun. 
to which it is assimilated, is in the system of the 
universe. Nstnre therefore must have concealed 
in this valuable body the most useful remedies ; but 
to make it lueful, in this respect, it is necessary 
that it should be introduced into the body in a 
liquid form ; it must in short be rendered potable : 
let us endeavour, then, to make potable gold. A 
life inde5uitely prolonged is certainly wordi all the 
treasures in the world. Such is in substance the 
reasoning of the alchemists, and therefore they have 
subjected gold to a multitude of uperationB, by 
moans of which they have pretended to render it 
soluble, like a ssit in water. The substjinee they 
produce has indeed the appearance of it ; bat to 
speak the truth, it is only gold very mnch sttenualedf 
and by these means suspended in the liquid : In 
short, it is in no manner combined with the fluid, 
and it even gradually deposits ttaetf at the bottom 
in the metallic form. 

However, the following is a process for making a 
kind of potable gold. We shall eiamine afterwards, 
supposing it to be a real solution of gold, whether 
it would possess properties so marvellous, and so 
salutary to the human body, as is pretended. 

First dis^uUe gold in aqua regta : mix this solu* 
tion with fifteen or sixteen times the quantity of any 
essential oil, such as that of rosemsry, stirring it 
round, and separate the nqua regia, which occupies 
the bottom, from the e-ssential oil. If you then 
dissolve this essential oU in four or five times its 
weight of well rectified spirit of wine, yon will have 
a yellowish liquor, known under the name of the 
potable gold of Mademoiselle Grimaldi. 

Vitriolic ether, and ethereal liquids of different 
kinds, possess the same property as essential oils ; 
namely, that of seizing on the gold dissolved in the 
squa regia. A kind of potable gold therefore may 
be made with ether. This gold may then be taken 
in drops on sugar, in Che same manner as when 
ether is taken ; for this liquor is not miscihle with 
water. 

The celebrated drops of General Lanotle are not 
difTcrent from the potable gold of Mademoiselle 
Grimaldi. It has been remarked that one oonce of 
gold wss diluted in 216 ounces of spirituous liquor, 
and as the bottles must have weighed two ounces, 
and as General Lamotte sold his for 24 shillings. It 
results that with one ounce of gold be made at least 
108 bottles, from the sale of which he received at 
least 2592 shillings. In reality he made 136, which 
were worth to him 3254 ahiUings. 

It hence appears, that if General Lamotte's drops 
were not useful to the health, they were exceedingly 
Uiieful to his purre. But what wilt not quackery 
efTect among mankind, when supported by ignorance 
and the love of life ? 

But let Ufl examine whether there be any founda. 
tion for Che wonderful properties uscribed to potable 
gold. A very little reasoning will shew that nothihg 
can rest on a slighter roundslion. What prooN 
indeed can the alchemists produce, that potable gold 
is salutary to the human body ? Because gold is 
the most fixed of all metals, because it hss the 
beautiful color of the sun's rays, because it is re- 
presented in chemical characters by the cbarac- 




188 



MAGAZINE OF SCIENCE. 



tcristio sign of that taminary, sre we tbeoce to cou- 
«lu<Ic timt, when reduced to a liquid form, and con- 
Tcyrd into iho blwd. U re^enenitec that fluid, re- 
noTBttTH youth, and restoret bealth ? What prnnn, 
ncrudtnmcd to deduce just consequences from anjr 
pnnriple, will ever form ffuch a concluaion ? All 
the virtues of potable gold are founded merely on 
amik-ffit'S, invented without any physical foundation, 
by frrvid imajtliiatioua, and by henda dentni^ed by 
the heat of tlictr fnrzwees. Tbia is the most favor- 
able opinion that caa be entertaiued ; for it is pro- 
bable that such ideas are aa much connected with 
impostoic. u with credulity and want of rcaaomng. 



BOTANICAL NOTICES. 

mEPRODUCTIVB ORGANS Or PLANTS. 

Tj^c ttameus and pollen. — A flower may be 
perfect without having eiihor calyx or corolla, bat 
Tint uiilcjtft it haTO one or more stamens and pointals, 
for tbeae parts are neoessarj to the perfecting of the 
seed. The itamens are situated next within the 
corolla, and in a ring around the pointal. though 
sometimes connected with either ont^ or the other, 
when their particular mode of growth or attachment 
occasion particular terms to be applied ; tliua when 
growing to the calyx or coroUa they are r*l]ed 
petit/t/nou», (1, 2,) — when under the pUlil. Aj/^d< 
j/yuutm, (3,) — or into the pistil, epifrytioiur, (4.j 




A atamen consists of three parU : the filament or 
tliread-ltke portion, the anther on the top of thiit, 
aod the pollen, which is a flne powder contained in 
the anther. Of thene parts the two last are never 
absent — the filamt>nt sotnetimrs is. Tlic anthers 
vary ocfnstderabty in eize, form, color, and manner 
of attachment to tbelr filaments, and nlao in their 
manner of opening, and scAttering the pollen. In 
general this is accomplished by the anther, con- 
fiisHrig of two cells, which open from one end to 
the other. sulTering the pollen to fall out. In other 
cases, though these arc not numerous, there are 
pores or boles upon a certain part of the anther 
througli which it rsrnpes. 

Stamens exint in plants not merely under different 
forms, but variously arranged ; most frequently all 
within the same flower, and nearly of the same 
length ; yet in whole classes a difference in them in 
this respect is perceivable, forming most essential 
difttinrtions; so also whether they may be free, 
thst is, detached from each other, or in any manher 
united, is no leaa necessary to be remarked, psr- 
tidularty In the arrangement of plants, according to 
a system of claasification. When stamens are united 
into one bundle by their filamenta, ibey, and sluo 
sach plants as have them thus, are said to hctnono- 
ttrtfiktmt, (1) — if united into two bundles, dimhl' 
p/iotut, (2) — if in more than two, pfrlyatlclphvus, (3) 




—if tmited by their anthers, theyaro called 
cioKJ, (4) — if of unequal length, thry may be 
didynamowi , {b ,) or trfrndynomotUt (6,) Mia 
in the preceding iUustrntion, 

The pttlien of pUnu ii s mott curioua m^ ban* 
tiful object for the microaoope. We are acciutoi&cA 
to tee it as a yellow powder frequently, but it 
means always takes this color, various 
orange, and through tliem to the bright bro 
are common ; ahades of purple, blue, scarlet, anil 
flesh color, are also frequent. In the garden tulip 
it is quite black — very seldom, if ever, grcea tff 
white. Pollen i« mostly spherical or otrI. 
timoB with a smooth, at others with a rongbcued 
mamillated surface. Other ahapea occur end 
of tbem extremely curious.* 

1^ putii. — Tlie pistil is the part in the ccititr* 
of the flower, always connected with the stalk vUffc 
boirs tlie whole flower, and remuaing attached to 
it long after the rest is faded or foUen. A peHbet 
pistil consiats of three parts i — First, the germot 
orary, which Is the lower part, and couatitntea tbe 
future seed vessel. Upon this is seated a thrcMU 
like portion, called the wlyU, The nmmit of die 
style is swelled out, and rough or sticky : this la 
the atifftHO. The ovary and stigma are never ab* 
sent — the style sometimes is, in which case the tap 
of the ovary itself is called the stigma, aa in f A* 
poppy, where it appears like the spokes of a whed. 

More pistils than one are very frequently mat 
with. In mony cases so DniLeit, that the ovary ap- 
pears but a single body, and showing its cotapomi 
character only by various divisions or du»epimfwi» 
as they are called, seen acrota it internally. In other 
examples every ovary is distinct from the r««t. Thv 
styles too ore united tbrongbout their whole lengtlif 
partially bo, or else entirely free from eadi other. 




I. A pcrfwipUtll A. The»Vftry. B. Tlwvtyto. C- 

fUania. £. Tbr ovwyeuiwron. •fa<->^ • '■■ »^ .i—m. .^t^ 

and li> biiv« Ibo seed* »t(icbi>c) lo .> 
ovary cut lengthwnyi, aboMiiis thi- 

rOU* UVTllM. 4 A I'UUI. W-llh i>VAt> 

n Mlylp. b. Four |)ialll«, wtlh ibolr uvnriL" < 
dlstltirL C. DIUu, Mritti ihcir oVxTtct <l 
unliod. 7. Dltiv. with lb«tr ityle* iNuily-.u.^. . 

The agency of tbeae varioaji parts in ixmdnrtnf 
to the perfection of the aced may be th': 
dmrribed. The young seeds are oontain' 
base of the pistil long before the flower 0|fcii», Mi<i 
continue to grow until that time, but nu loOfff^ 
unless they are acted upon by the pol)<in Of At 
anthers. Then they, in eome manner wholly onae- 
countable to us, become fertile, increaving in eia 
and perfect structure until ripe— when the aeail 
beiDg scattered, they grow and produce other planll 
like that from which tliey sprung. 

The reason of such an influence of the poUctt ll 
unVnuwD, but the manner by which it rrachea llM 
nvary is rnsily rrplaioed. VThen the anthers borvl, 
the pollen falls upon the atigma, aome of it peoa* 
tratea this, and arrivea at and paaaea along the styU^ 

* An arcounJ of the poUeo of planta as a uvcriMcapK afc> 
ject, bus hn-tt hilly iirnnbcd ta VwL 1. p«it* tlQ. mkm» 
fHifflctvUd Ojjurci irr ghco. 



MAGAZINE OF SCIENCE. 



k nms^ta the germ or baae of the pbtU, 
DDnf seedx are contained. 

it7 of this prooew tbovi how it is thAt 
bd pistils are so constantly fonad in 
3 «Iu why the stftmcns surroand the 
tcely as in ^oeral they do ; and in cir- 
where this is not the case, stilt some 
Dntrivance is fonnd for the some end. — 
in their search for the honey of nowers. 
tn scattering the poUen from the anthers 
ftigms, and the cunveyiince of it from 
iwet-^wbite the sapcrtluoos poUen which 
upon their bodie-s is supposed to coo- 
lie formation of the wax or honeycomb. 
Mrry borne to the hive, and there, like 
Bta, contribute to the general welfare of 
pity in which they dwell. 
itaele is that part of the pedancle npon 
e <aiious loner parts of the flower are 
iDovt plants it presents no appearance 
notice — in others, however, it is some- 
A: fbc cxunple, the fruit of the rasp- 
blackberry easily come off, and show 
Im a thick, fleshy receptacle. In the 
the whole frnit, (except the seeds upon 
irptacle. In thuecmniam tribe, it growl 
point, beariog the seeds from its sam- 
a grasses, the part of the stalk which 
is also culled a receptacle ; bat it 
s of compoiind flowers that the recepta- 
varied and most important. In the 
ronical ; in the dandelion round. The 
it hairy, and tlip rhnmomite scaly : be- 
omerous other distinctions. In truth, 
this class, (the nineteenth, syngenesia.) 
roost partj distinguished from each 
shape of the receptacle. 

CTo le continued- J 



«G DAGrERREOrVPE PL.\TES. 

ng of the Electrical Society, in the Ade- 
rj. last week, a communication was re- 
Mr. W. B. GroTr, on a voltaic process 
Daguerreotype plates, and printing from 
;» il is true, as yet with the clcHrne^^ft and 
an ordinary etching, bat with all the ac- 
delictcy of the orifiinol Daguerreotype, 
vy promise of perfection. He says, the 
■MMos the advantage of simplicity, 
!• a perfect etching of the original image ; 
>, indeed, that a plate thus etched can 
diatiaguished from an actual Daguorreo- 
rring ail the microscopic delicacy of the 
of the impression. The secret of this 
fco make the Daguerreotype the anode of 
ahination, which will not of itself attack 
or mercary, bat of which, when elnc- 
aoioD will attack these metals unequally. 
the luual explanation of the Doguerreo- 
k supposes the light parts to he mercury 
rk silver, the object was tu procure a ao- 
Eh would attack one of these and leave 
ntonched ; if one could be found to at- 
ver, and not the mercury, so much the 
this would give a positive engraving, or 
tie tights and shadows as in nature ; but, 
elj. ail ver and mercary are nearly allied in 
heal relatione. Mr. Grove made several 
Is with pure silver and mercury, nscd as 
of a voltaic combination, but found that 



any solution which would act on one acted also on 
the other. All then that could be expected was • 
difference of action. With the Daguerreotype pUtes 
he has useil the following :~Dilute sulphuric acid, 
dilute hydrochloric acid, solution of sulphate of 
copper, of potash, and of acetate of Uad. Bat, 
after many experiments, hydrochloric add was fixed 
npon OS decidedly the best ; this had been expected 
from the strong affinity of chlorine for silver. The 
manipulation employed by Mr. Grove and Mr. Gas- 
slot, in the laboratory of the Loudon Institution, 
was as follows :— -A wooden frame is prepared, 
having two grooves at 0*2 of an inch diitance, into 
which can b« slid the plate to bo etched, nnd another 
plate of the same size of platina ; this latter is pla- 
tioised after Mr. Smce's method, to ensure a ready 
and equable evolution of hydrogen ; for if the hy- 
drogen adhere to any parts of tlie cathode, the op- 
posite portions of the anode are proportion ably loss 
acted on. The back and edges of the Doguerreo- 
type are vamished with a solution of shell-lac, 
which is scraped off one edge to admit of metallic 
connexion being established. The wooden frmmei 
with its two plates, is now fitted into a vessel of 
glass or porcelain, filled with a solution of two mea- 
sures of hydrochloric acid + 1 distilled water, (sp. 
gr. l-l ;) and two stout platina wires proceeding 
from a single pair of the nitric acid battery, are 
mnde to tooch the edges of the plates, while the 
assistant counts the time — this should not exceed 
30 seconds. When the plate U removed from the 
acid, it should be well rinsed with distilled water ; 
and will now, (if the metsl he homogenons,) present 
a beautiful Sienna-colored drawing of the original 
design, produced by a flira of the oi ycbloridc formed. 
It should now be placed in an open dish, containing 
orery weak solution of ammonia, and the surface 
gently rubbed with very soft cotton, until all the 
deposit is dissolved. As soon as this Is ofTeoted^ 
the plate should be instantly removed, plunged into 
diitilled water, and carefolly dried. 

The process is now complete, and a perfect etching 
of the original design will be observed. Tliis, when 
printed from, gives a positive picture, or one which 
has its lights and shadows as in nature, uid which 
is, in this respect, more correct than the original 
Daguerreotype, as the sides arc not inverted. Print- 
ing can therefore be directly read \ and in portraits 
thus taken, the right and left sides of the fkee am In 
their proper position. With respect to prints fron 
Daguerreotypes, there is, however, this difficnlty ; 
if the phite be etched sufficiently deeply for a good 
impression, some of the finer sludes of the original 
must inevitably run into each other, and thus the 
chief beauty of these exquisite images be destroyed ; 
if, on the other hand, the process be only continued 
long enough to leave an exact etching of the original 
design, which can be done to the minutest perfec- 
tion, the very cleaning of the plate by the printer 
destroys its beauty. At present, Mr. Grove con- 
siders the most important part of the process to be 
the means it offers of multiplying indefinitely 
Daguerreotypes, which, when thus etched st the 
voltailc anode, wHl admit of any number of copies 
being token from them by the electrotype process ; 
and, to give an Idea of the perfect accurticy of thesOf 
there was one on which was a sign-board neasur- 
ing on the electrotype ooppcr-phite 0.1 by 0.06 of 
an inch. Five lines of inscription can, with the 
microscope, be distinctly read. 



^^ 




190 



MAGAZINE or SCIENCE. 



t 



ON THE REFINING OF SULPHUR FROM 
, EARTHY MIXTURES. 

When salpbur U found in combination with earthy 
natter, it« purification generallj consists of twodis- 
tUUtloDf ; the first rongUy peiformed on the spot 
where it is obtained, with Uie object of rendering 
the cost of carrisge less expensive ; the second is 
made with more care, near the spot where it ia 
brought to market. At Solfatsra the first distilla- 
tion ia executed in a furnace, or galJerr, in wbieh 
are arranged ten or twelveeorthen pots, about twenty 
inchca apart, in two ranges — each of these pots 
containing about thirty pints. When filled with ore, 
broken to the size of road metal, the top is luted 
down, but there ia a tube connected with an opening 
in one of the sboulden of the jar, about two inohea 
in diameter and fourteen incbea long, which com- 
muoicatea witli a second jar, pierced with a hole at 
the bottom, from which the sulphur dows into a tub 
of water, and is then condensed — it ia subliined in 
the fint jar and cooled down in the second. At 
Maraeilles there is a large estabUihmeot for the re- 
fining of Bulphor, conducted by M. Micliel. who 
invented the appuratna; it conaista of a caat-iron 
fetort, and a vast chamber, which aerrea aa a con- 
doctor. The retort, containing about 1,600 or 
1,600 Iba. of material, ia heated by a furnace, which, 
bowerer, haa no communication with tbechitmber or 
the retort ; an iron door in front serres to clear and 
n-cbArge the retort, the beak of which conduct! the 
loiiica of the sulphur to the large chamber, where 
they are oondentted and collected either in a liquid 
state, or as the flowers of sulphur ; the temperature 
of the condenser alone effecting the condition in 
which it ia obtained. Much care is necessary to be 
obaerred in this process, aa the admixture of a Tery 
suall portion of air with the fumea in the chamber 
gives rise to exptoaionn, which are aometimes dan- 
gerouB, for it often happens that the temperature of 
the chamber is carriefl to the height of 150°, (suf- 
ficiently high to inflame the sulphur ;) aulphuric 
add ia then rapidly formed, and in this process much 
beat ia given out, and an explosion alwaya follows. 
By valves placed at proper places tbis may be 
avoided, and the chamber should be freed of its oxy- 
gen by baming sulphur, or charcoal, in it before 
commencing to operate. Of late years the method 
which has been adopted, termed " dt-cantation," has 
greatly removed the diflScolty of the process, aa 
explosiona are now seldom kiiow to occur. Thia 
arrangement conaiats in placing a large vessel, filled 
with crude aulphur, above the retort of diatillation. 
■Dd allowing the heat of the chimney to act upon it. 
A tube is made to wind round this vensel, forninhed 
with valves, to permit the melted aulphur to flow 
through it, and communicate with the buttom of the 
retort containing the sulphur to be disUlled ; thia 
disposition baa the advantage of maintaining a more 
nniform temperature, and rendering the operation 
more rapid. By the ordinary method the lose 
amounted to about 18 or 20 per cent, but by M. 
Miuhel'a modification the locals reduced to 11 or 12 
percent. Notwitbatanding tbeac precautions, the 
fumes of inlpburic acid, which (>«ca|>e when o(>ening 
the chamber to extract the sulphur, or clear it out. 
frequently destroya all vegetation in the neighbour- 
hood ; it ia, therefore, important to construct them 
BO that the sulphur can be withdrawn without en- 
tering the cluLmber. Eight or nine chargca are 
usually evaporated before ru^ining off the sulphur. 
It is of great importance to have thermometers in- 




aert«d in the chamber, at aoch pkeea as they 
observed, aa we have seen that, if the aali 
above the temperature of 1 10'^, and saddenly < 
it losea its citron color, and ia not ao ti 
marketi although equally pure. — JimiMf , 



IMPREGNATION OF WATER 
OXYGEN. 

fjtfwvwml from pnge IBS, ond 



"7. The fluid which now cootaina only 
chloric add, water, and oxygen, ia placed 
glass it waa first prepared in. and iu tempi 
lowered by Ice, aa before. Then, atirring i 
tinually. sulphate of silver, prepared by dlai 
oxyde of silver in sulphuric acid, ia to be add 
small quantities at a time ; and it is eaoentii 
the sulphate containa no free oxyde. The mi 
ia decomposed by the hydro-chloric acid, anil 
results water, chloride of silver which precip 
and sulphuric acid in place of the hydro-c 
When the quantity of aulphste of ailver ad 
sufficient to decompose, perfectly, all the 1 
chloric acid, the fluid tuddeoly becoroea clear ; 
that ia the caae it remaina turbid. As it ia re 
that no bydro-chloric acid should remain, a 
no excess of sulphate of silver should be pn 
and therefore the fluid must be tested snccei 
by nitrate of silver and muristic add, Tery 
quatitittea nf the fluid being used for this pur 

** When the proportions are well odjoate 
fluid is to be passed through a filter, and tlM 
after being allowed to drain, ia to be compfes 
a clotb. The fluid obtained by the cximpn 
must be again paaaed through a filter, in coaeeq 
of a alight degree of turbidneis. 

" 8. The object of the prednling opermtioi 
been to obtain a fluid composed of water, m 
and sulphuric add. But thia acid muat be 
rated ; for this purpose the fluid ia put ioto a 
mortar, surrounded by ice, and staked bi 
very pure and finely powdered, is to bo addi 
amall portions at a time ; it ia to be rubbed 
in the glass mortar, and when It ta all united 
acid, a fresh portion ia to be added. Wbe 
fluid scarcely reddens litmus paper, it is , 
filtered, and the filter comprcssMl in a doth ; 
after having united the two fluids, they are 
stirred, atid the saturation of the acid com 
by barytea water. There rouat even be a 
excess of barytea water added, to separate all 
of iron ; and, above all, of mangaoeee, wbio 
fluid may still contain; and it is) of importa 
remember, that it muat be filtered immec 
after* with all the precautions before given. 
excess of barytes may then be predpitaCed 
few drops of weak sulphuric acid, and It ia 
to leave a alight exceas of the add preseot, : 
than of the base, becauae the laat tenda to Urn 
oxygen, whilat the first renders the eombii 
more permanent. 

" 9. Finally, the fluid, which may be OMtfi 
OS pure oxygenated water, diluted with em 
water, ia to be put into a clean glasa hsTiog i 
and thia glass placed in a large capsule, two- 
full of concentrated aulphuric add. This sppi 
is to be plsced in the recdver of an air-pumj 
a VBCttttm made. Pure water having a g 
tension when in vapor than oxygeiute4 | 
evaporates more rapidly, ao that at the end 
days, the fluid will contain perluiia two bn 




MAGAZINE OF SCIENCE. 



191 



and fifty time* tU Tolomn of oxfgen. The foltow- 
ii^ oburratiooft must be attended to : — 

** The add mast be ablated from time to time. 

*' It happ«D« aometimes that towards the end of 

■poratioD. the fluid difengages t little g«i, 

ID indicated by the variation of the meroary 

ill ihi: gaoge. This diseoi^agement is occaaioned, 

DO doabt. by extrmseotu tubstancei which remain 

Ui the fluid ; it may be stopped by the addition of 

i«o or three dropc of extremely dilute sulphuric 

add. 

*' Sometimea the Add will depoait some white 
ItoewJi of ailex. These ahoold be separated. The 
■old may be decanted by o pi|»e with a very tine 
Mmmaiion, and but a small qnaoiity of it will 
Wlost. 

" Until the fluid becomes rery concentrated, the 
w porarion goea on very quietly, but when the 
Myienated water icnrcely contains any more water, 
kublea frequently rise, which burst with difficulty. 
hi finC fight, it Be«ms ai if much oxygen gaa 
neaped, but on uamining the gauge, it will appeor 
Ttrytriflinin:. It will scarcely become sensible in 
twraty-four boun, and the olteralioa then ob- 
strred, is in port occasioned by the diaengagement 
if pu (foo^ the sulphuric scid, belonging to a 
"^'*-^i of the oxygenated water which has been 
jted. 
I be fluid may be known to be in the most 
eoerrotrated state poasible, when it gives four 
luBdred and scTcnty-fiTe times its volnmn of oxy- 
gen tf the pressure of 30 inches, aud temperature 
of 57'2 Fabr. This proof is readily made by taking 
amiall tube, on which a line la marked, and Ailing 
it vith tlie fluid up to the line, and then diluting 
^ quantity. wlu|k, in my experiments was 
oface^br, (0,030514 of c : i :) with 
its tolumn of water, and decomposing 
s certain qoantity of this last fluid by oxyde of 
si)n;;aaeae. This last experiment consists in flUing 
I cube 15 or 16 inches Long, and 7 or 8 lines wide, 
with mercury, to within an inch of the top ; then 
faitrodacing the portion of diluted fluid, of which 
Ac ooolyala is to be made, using for thi;; purpose a 
Small tube of known capacity, afterwards filling the 
Wbcwttb the water used to wash the small measure, 
sr parity with mercury, and then, by closing the 
tibe with a valre covered with tallow, inverting it, 
ling in a tittle oxyde of manganese diff'used 
The oxygen will be immediately dis- 
and nothing further is required than to 
the tube with the hand, and shake in different 
directions, that the contact of the oxyde of monga- 
oose and the water may be ensured, and to measure 
IbegiA," 

INDIGO. 

btBiAO is obtained chiefly from diffrrent species of 

imiS/iTM,an American and Asiatic plant, cultivated 

as • ftoaroe of this article ; it is also ubtuined from 

-rzinN Hnciorium ,- and from some species of 

or wood. The dye is extracted either from 

tuf fa'eih or dried plant, by safTering it to ferment 

4tb water, during which it undergoes chemical 

kasgea, which ultimately cause its deposition in the 

•m of a blue feculent deposit, which tn collected 

d dried. The genera] characters of indigo, as it 

tooad in commerce, ar« the following : — it occurs 

■quare cakes, or cubical maoaes of a deep blue 

lor. and generally containing about 50 per cent. 

pwT ooUinng* Blatter, which is perfectly insoluble 



in water -, when heated to between 500^ and 600°, 
it aff'ofda a sublimate in the form of a blue smoke, 
which, on condensation, forms acicular crystals, 
amounting in weight to 18 or 20 per cent, of the 
original Indigo. It is soluble in conoentrated nU 
pburic add. This solution is usually called Saxon, 
or liquid blue, and is used as a substantive color 
for dyeing cloth and silk. Substances which power- 
fully attract oxygen render indigo green, uid bj 
exposure to air» it again acquires a blue color. In 
thia green state, indigo is soluble in the alkalis, and 
the solution is commonly employed for dyeing calico. 
A bith for this purpose may be made by mixing I 
part of indigo, 2 parts of sulphate of iron, and 2 of 
lime, in a sufficient quantity of water : in this caae, 
the sulphate of iron is decomposed by a portion of 
the Lime. The protoxide of iron ^us produced 
becomes pcroxidizcd at the expense of the indigo, 
which is rendered green and soluble in the alkaline 
liquor ; cotton steeped in this solution acquires a 
green color, which, by exposun; to air, and washing 
in water acidulated with sulphuric add, becomes a 
permanent blue. A tittle iron or zinc thrown into 
diluted sulphate of indigo changes or deatrayi the 
color in consequence of the evolution of hydrogen ; 
the color is also quickly impaired and destroyed bj 
chlorine. 

Indigo has been subjected to an interesting seriM 
of experiments by Berxelius, who found its uattd 
canstituenta to be four dutinct subitances : vix., I, 
gluten; 2, a peculiar brown substance, apparently 
resembling extract i 3. a red substance, which givea 
a white sublimate when heated in close vessels ; 4, 
indigo blue, 1. The substance which BeneUna 
terms gluten, is soluble both in alcohol and water, 
and woa obtained by digesting powdered indigo in 
dilute sulphuric acid, neutralizing the solution by 
chalk* filtering, evaporating to dryness, and digest* 
ing the residue In alcohol. 2. The brown matter 
was taken up from the indigo (freed as above from 
gluten) by potaasa, and neutralixing the solution by 
sulphuric add ; this occasions a precipitate contain* 
ing a peculiar brown matter. 3. Upon the indigo, 
purified by dilute acid and by the action of solution 
of potassa, strong alcohol was digested, which takes 
up a red substance, insoluble in water and alkalis, 
Boluble in concentrated aalphoric acid, and in nitrio 
add, and which, when heated in vacuo, yields a 
grey crystalline sublimate. 4. The substance re* 
maining after the action of the above solvents is tho 
real coloring matter of the indigo, or indigo-bhie, 
and ia that which forms the purple vipor and inbH* 
mate above nUuded to. It forms a deep-blue solu* 
tion of great intensity with sulphuric add, and espe* 
ci&Uy with the fuming and partly anhydrous add 
^Nordhausen add), and is, in fact, the principal in- 
gredient in the sulphuric dyeing-liquor already 
mentioned. 

TAe oc/ton qf tulphurie add upon indigo haa 
been investigated by Mr. Crum. The conoentrated 
add doea not merely diaaolve it, but, in the couroe 
of twenty-four hours, alters its properties ; it at first 
becomes yellow, in consequence, probably, of the 
abstraction of the elements of water, for much heat 
ia evolved, and the addition of water instantly fe- 
atores the blue tint. Nothing ia given off or ab< 
Borbed, nor is carbon precipitated. When the snl- 
phnric solution ia neutralized by potossa, an io- 
tenaely-blue predpitate falls, soluble in water, but 
insoluble in saturated solutions of the aalti of po- 
tosaa ; it was, therefore, purified by alternate wash- 
ing with solution of acetate of potossa and alcohol. 



192 



MAGAZINE OF SCIENCE. 



XKHien dry it icqnircft a copper<cnlor, U very hy^A- 
metric, soluble in HO' degrees of cold, aad in ■ 
smaller proportion of hot wat«r. The cold solation, 
erea when Ifti^ely diluted, forniibes inioluble pre- 
dpitateii vitlt talU of poUua, soda, Ittne, baryta, 
•bDntia, lead, and mercury. Thia snbatjuice has 
been called Cerulin, and ezista in the precipitate ai 
& cenileo<Balphate of potasaa : it appears to be a 
hydrate of indigo, in which 1 proportionai of indigo 
is combined with 4 of water. 

By UmitiDg tlte action of the acid upon the indigo 
to three or four hours (or at 100° to 20 minates), 
differeat reaults are obtained. 1 part of purified 
^ indigo waa ahaken in a phial with 10 of lulpharic 
add till it became green, it was then paureo into 
water, and filtered. Tht first washings of the sub- 
stance upon the filter ore to be rejected ; hut when 
the liquid posses uf a blue color, solution of chloride 
of potassium may be added, which throws down & 
purple precipitate, called by Mr. Cmm, PAenicin, 
This BubstaQce is soluble in water and alcohol ; it 
is converted by sulphuric acid into ceruUn ; it ia 
precipitated by almost all saline substances of a 
purple color ; it appcnrs to contain 1 proportional 
of indigo and 2 of water. 

MEMORANDA. 

RcGHAULT* in his researches on the specific heats 
of compound bodies, either liquid or solid, arrives 
at the foUowiug concUuions : — 1 . In metallic oxides 
of the same chemical formula, their specific heata 
are in inverse proportion to their atomic weights. 
2. In the aulphatea composed of one atom of kuI> 
phur, their specific heats are in Inverse proportion 
to Ihoir atomic weights. 3. In compound bodies, 
having the aamc electro. negative olementa, and a 
Iflbe atomic constitution, the specific heats are in 
Inverse proportion to their atomic weights. 4. In 
all compound hodieii of the same atomic composition 
and chemical constitution, their specific beats are 
in inverse proportion to their atomic weights. — 
Compia JUndua, 

Length of Dayt. — At Berlin and London, the 
longest daya haa 16 hours and a ^. At Stockholm 
and Upsal, the longest has 18 hours and a 4, and 
the shortest 5 and a ^. At Hamburgh, Dontzic, 
and Stettin, the longest day hai 17 hours, and the 
ahorteat 7. At St. Peteniburgh and Tobolsk, the 
longest hss 19, and the shortest b hours. .\t Tor- 
neo, in FinUod, the longest day has 21 hours and a 4, 
and tlie shortest 2 and a i. At Wardorbus, in 
Norway, the day lasts from the 2Ut of May to the 
22nd of July, without interruption ; and ia Spitx- 
bergea the longest buts 3 months and a ^, 

*V«o Plan of Launching S&ipM. — The Liffcy, 
West.Indta mail packet, has been launched from 
Mr. Wimshurst'a patent steani'Ship building yard, 
MiUwall, Poplar. The Lifl'cy is considered a very 
aharp vessel, and was launcfaed on Mr. Wimsburst's 
plan. In lien of cleats, &c., nailed or screwed to 
the bottom, a rod of iron is bcut round the top of 
the poppets or slopings up on both sides, past under 
the keel, and shackled together ; a chock of hard 
wood is fitted between the keel and rod, with a wedge 
driven between the keel and chock to tighten the 
poppets to the vessel's bottom ; then set the vessel 
up in the usual way with drivers. A chain being 
attached to the irons drawa all out clear when the 
TCaaol goca into the water. Vessela of the largest 



si/e may be coppered and fitted rcAdy for' 
launched on thja improved plan, without 
dock. 

A>fr Indefibte Ink, — M. Beranger has 
French Academy of Sciences, a descriptit 
economical ink, for which he has taken ou>i 
It oonnsta of lamp black mixed with 
caostic soda. By adding an aromatic 
ink, it is difficult to distinguish it froi 
ink, its qualities being the same alki 
delibte, but its coat much leas. — Mo 
duftriet. 

Advantage qf Planting Fntii Trwttm 
— Dodart first observed that trees pi 
branches iu a direction parallel to the sui 
earth. If a tree stands on a steep it 
towards the hill, and towirda the dDClii 
both sides it still preserves its branches 
the surface. As there is an attraction bet 
upper Burbce of leaves and light, I am al 
snaded, though not equally certain of it froa 
rlment, that ^ere is on attraction of the same 
between tlie under surface of leaves and the 
of the earth. This 1 consider the true can* 
phenomenon. I had long observed that tk 
fruitful orchards and most fertile trees ar 
planted on a declivity, and the steeper it is, 
not quite a precipice, the more fertite they 
It is well known that the spreading of trees 
renders them fruitful. On a )plaia they Im 
shoot upwards; and therefore art is eupk 
skilful gardeners, and applied in Tarioos w 
check their perpendicular, and to promote t 
teral growth. But this point is obtained 0« 
olivity by nature. There a tree loses its M 
to ahoot upwards, and in fldbr to presc 
branches parallel with the su^^, is cousta 
put them in a lateral direction. Hence aj 
tant rule in the choice of orchards andfmilg 
— i?ep. D, J. Walker. 

Gahano-plaxtie Wondert. — A letter from \ 
informs us, that the celebrated Bavarian u 
Stigelmayer, haa brought to such a pitch 
fcction hia galvano^plaslic process, that its 
would be deemed fabulous were they not ] 
exhibited in the Museum of the Sodety c 
In the apace of two or three hoora roloaaal 
in plaster are covered vrith a coat of copper 
takes with the greatest accuracy the moat mia 
delicate touches, giving the whole all the app 
and solidity of the finest casts in bronxe. 
gelmayer has also applied his prooesa to the i 
objects, as flowers, plants, and even insects, 
ing them out with such sccnraoy, that they 
have been executed by the bands of the 
artists. — Literary Gazette* 

Hetftpfrom Bean Stalks. — Every bean^ 
20 or 30 fibres, running np on the outer siJ 
D thin membrane from the bottom to the to| 
plant. There is a particular fibre at each of 
comers of the plont, rather thicker and stranj 
the rest : it is sometimes made use of 
instead of i«a grass, for fixing their hnol 
fibres are easily separated after the pl 
soaked 10 or 12 days in water. Woshingl 
it through hackles or iron combs la 
dressing bean hemp. It is not rei|tujdte < 
stalks should be kept exactly 12 daya ntidai 
they may remain any length of time, ao tl 
are either quite under water, or perfectly dl 



n 



Istranj 
of ta| 

inoH 



LOKDOH.— Pnatcd bv [>. Kra^cii. 6. White Hone Loo*. MII« End— Publishad hy W. Bam Am, ll.PatenBl 
Edlntwrgb, J. MstiSiaa— ClBsgow. O. fiaics and J. Baaxas.— UverpooJ, J. Paiur. 




IS-I 



MAGAZIVK OF SCIENCE. 



ELECTRO-MAGNETISM. 

f Beiumeil from page \TL) 

Wi hMt, i>rrhapSt lafficiently expUined the Bction 
whicl) magiitta aod wire*, conveying a carreot of 
electrirtty nlong tbcm, mutuiiUy «ert upon each 
other, in proUuciDg vibratory and roUtory muve- 
menU. There are, howcTcr, naroerous experimcnt& 
equally couclusive, and perforcned with more oon- 
Tcnient api)Aratas than Home we havr had oco-Asian 
»o introduce; we therefore rerert to what is paited. 
ud theu pumue the subject further. It was shown 
in page 37H. rol. ii., that a wire which conveys the 
«lectric fluid along it, provided it wefc free to move, • 
would revolve around the pole of s magnet placed , 
under it, aa wai proved by Or. Faraday, a section 
of whose apparatus may be s^en in fig. 1, whert; 
A shows the pole of a mngntU— B a foot-stand, 
with i mercury cup, communicating by a wire with 
the interior of the glnss tube C. Tliii tube contains 
a Httic mercury sufficient to cover the end of Ihc 
wire I, which leads from the hooli of a second wire 
at the top. such wire passing through a corkt and 
temiiniiting in a mercury cup K at top. 

In this appAnitit«i it i» evident that when the cup 
E ia connected with the positive pole of a galvnuic 
battery, the other pole being aino connected with 
the lower rup, the lluid will have no cbflnuel but 
along the wire I, and the consequence will be that 
it will revolve around the magnet pole. 

A much more conTcnieal form of the apparatus 
is seen in fig. 'i, wh**re A is a cover or case of 
paper that fits upon the pole of a Urge magnet. 
B is a circular wooi-len trough for mercury, having 
• cup P. C is a wire to support the mercury cup 
E, and the suspended wire D. If one wire thus 
revolves, »o would two, ruid so would any number 
of wires, and this whether the wires were distinct 
from each other or united together; and as a 
cylinder may be considered but as an aggregation 
of wires, a meUUic cylinder, placed in the same 
oiroumstAuces, would in like manner revolvs. This 
fact, which was fully established by Mr. Barlow, 
raggested to Mr. StnrReon an eiceedingly elegant 
apparatus, called Sturgeon's crown. Two of them 
ore shown, as placed upon the poles of a horse-aboe 
magnet A H, (fig. 3.) From the raercary oapi at 
top K K proceed straight wires, pointed at their 
lowrr end, and renting in an agate cup on the top 
of the magnet. To the wires are soldered a piece 
of thin brass, cut like the Hpokes of a wheel, from 
a round piece in the centre. The spokes being bent 
down are Koldered to a riiu, as repie«euted. The 
lower end dips into mercury, with which the cups 
J J are united. 

It may be oaked why there ore two crowns shown? 
It ia because the direction in which the wirrs turn 
depends upon Turious circumstances, particularly as 
to the direction in which the current of electricity 
is made Co pass, and the pole of the magnet round 
which U revolves, whether north or south. The 
course of rotation of the wire, nnd coniM'quently of 
all other apparatus of the nime kind, will be from 
left to right, or the some with that of the hands of 
a watch, when the electric current is descending 
along the wire, and the upper end of the magnet is 
the south pole. The motion is reversed when either 
of these conditions is reversed. This may b« con* 
Tenicatly exhibited in the two poles of tKe same 
viacatt by employing a horse-shoe magnet, as re- 
opesented m (ig. 3, where A B F is the magnet. 
£ the sund of t(. D C two screws holding the 



magnet in Us proper pUct-. by a cover to the Unt«r 
port of the stand. As the magnetic powvr pcne* 
trmtei tlirough all obstacles except irnn, the t^^gi of 
Che magnet A B may be covered wiili hnus case* 
without impairing tbeir effect. From what has 
been said, it ia evident that if two crowns «rr 
suspended one over each pole of the magnet, the 
current descending or ascending iu boCbi thry will 
rotate in contrary directions. 

If a spiral wire be substituted for a straight (Nie. 
It will in like manner rotate ; a wire of this form U 
*cen in fig. 4. where D D are the mercury cufw. 
C C the wire ; and A B one pole of the niagoet. 

There is another point of view in which we have 

not yet considered the subject. It is that to which 

the magnet not merely oflects a oonducttng wire, 

but the electro- magnetic battery itaelf. It i» foand 

that the stream of electricity, which la paasiog 

through the voltaic battery itself, frum its m ^ g olttO 

to its positive pole, t%\\ ibits the same eleetra- 

mognetic propertiea that it does while pasting aloag 

the wire, which completes the circuit by connncS- 

ing the two poles ; for a magnetic needle placed '\M 

the vicinity of the buttery, and in rircumftaMH 

equally favorable to the action of the corrent, wUl 

he affected iu the same way as it i& by the win* 

itself. Now as all action implies a correspODi' 

Olid ujual rc-action. it is reasonable to ioforl 

as the battery produces motion in the rosj 

the magnet mi^ht be made to move the battery, 

a saffioiently delicate suspension could be conthrad 

for the Utter so on to render its motion wTwhle. 

This object has been Accontplisbed by AT'iH^rc. 

The apparatus he used coDSiKted of a doable cy Imdrr 

of copper B B, (fig. 5,} closed at the bottom anJ 

supported by a wire across the top of the tnotf 

cylinder, upon the pole of a magnet. Upno t 

mercury cup, connected with this wire, is n(pf0dcd 

a second wire C C, bearing at the bottom of Its 

ring of zinc. When a dilute acid ia poured faUo 

the space between the two copper cylinders so u to 

immerse the ring of zinc, the whole forms a gil> 

vanic circuit, the moveable part of which viH 

rapidly rotate; if the copper be fixed, the sise 

alone will move ; but if the copper he made 

than the top of the magnet, and fre^y las] 

upon a second |koint, as was suggested 

Marsh, and as we have represented, the 

vessel and contents will rotate in one dii 

while the xinc and its wire will take the 

The apparotns may be still further varied Uy 

posing the cop|ter vessel to be fiird nii the msgad. 

and not forming a part of the battery. The fil- 

vanic action arising from a rim of line, as bcAirSr 

and a similar but rather larger rim uf copper 

arm of wire, as represented in fig. 6, where 

the fixed copper cup. B B the wire of the 

rin. C C the wire of the line rim ; oad 

magnet. In this apparatus the sine and 

rims turn different ways, and with greater P 

than in the former instance, the liquid not 

tu lie carried ahmg with it. We must di 

another opportututy the concluding part 

subject, vix. the effect of clectro'isagnett 

each other ; and thia will explain to ns more 

ticularty the action of electro-magnetic machini 

and how it is that electro-magnets, tboogh 

attraction, repuluon, and other properties, 

upon the same laws as ordinary magnets, 

accomplish what magnetism alone is unable to cAct^ 

f T9 i« cv»tamvM- } 



NFAGAZINE OF SCIENCE. 



)« 



ClmRENTS OF THE OCEAN, AS CON- 
NECTED WITH GEOLOGY, Ac. 

Navioation Mem« inLloiktely connect«<l with 
^talogy u B science. Beoaua the oallinei of our 
OBTCb* M dividol into laiiil and water, bivin; bceu 
determined prtmarily by phyncal fon!e$, or the 
•dioa of oceHQic camnti. and the flui of tides 
therefrom, ab they still cither set or run — asrendiog 
from An uplifted order out of rocks, to deposits of 
iodarsted mud, cemented sdnd-stooe. a concrete of 
limestone, and aggregates composed of debris from 
■11 Llial had gone before, so hare these currents of 
the ocean, or the lidea flowing from them, cither 
•eoored out deep water, covered various shores and 
•eaa with «)iallows composed of sand, silt, or shinitle, 
or hare formed by sach physical agency those 
natural havens into which sea ves»e}s may be safely 
niTigAtrd, anchored, or seeurely moored, A Utile 
•iceatioD to physical laws must abundantly satisfy 
cny body, Ciipable of assorting and classifying ordi. 
nary thoughts, that physics in organic fonns not 
only constitute* a leading instrument by which in- 
trlligence, either divine or human, works out its 
ciuU, but u placed in the hands of Almighty fore* 
llMwledge. in some measure cxplain<) the sequence 
tnd myvteries that belong to the order in time in 
which the earth has been constructed. Tbe sun 
■oald appear to be the main driving power, through 
fti ncdiam of highly-elastic agency, that works a 
ffsfiem of which it is the common centre ; and 
without asking what Hca beyond the sphere of these 
Origanic furccs, we may, iti the dnt place, consider 
the cArth aa a member of the solar system, pext as 
iaTolviag tbe moon in its orbit, and finally as the 
ofiginAtor of foroca that wholly belong to itself, and 
have been intimately coneemol ia working out the 
imTtdtiiitiai frame of its own construction. Let 
tbe sun as a driving power, therefore, be taken at 
wme determinate rate, then tbe earth in a primarilv 
■ebular form, as s body neither much compressed 
&or condensed by organic forces, on the law that a 
bj^Il composed of pinc, with Aoy given diameter, 
vcn by some given pnwer, would move in a 
•ndiog orbit and revolve on its axis at a 
-ate of speed than a ball having a hkf^ dia* 
nd placed under consimilAr terms would do^ 
II coMijHJsed of heart of oak. So would tbe earth 
niAfe slower in its orbit, and revolve slower on its 
Avia. accordingly as its volumn or diameter were 
oDtnprcssed by the centricity of gravitation, and 
progiTMively condensed to the solidity and dia- 
meter it tK)W maintains. The motion of the earth, 
tKercfore. io Ita orbit And on its axis, in conformity 
to A plain rule in physics and organic forces, may 
be truly inferred to go now at a vastly reduced rate 
of speed, than in a nebular state ; and when an 
ttceas of speed caused its form to take that of an 
ohlAte spheroid. And thereby bAlance itself on its 
ads, by its most elongated zone hnving a conotant 
tczkdency to sink downwArds (on the principle that 
vcikU float,] And necessarily re-oscend again in 
alteroAte revolutinn*i, until a rompre5L«i-d and con- 
r 4aDscd nucleus, by an excesr^ of speed in a liueal 
► £ractioo, or by «n eiccss uf centrifugal fore**, threw 
m( lines of rooks longitudinally acro5B the equator, 
. the equator ia the diiectiuo of the poles of 



•Ton 



:;rranite formation and the rest of its 

re, had been so lifted from or pitched 

- of the earth by centrifugal force, 

'ion in its orbit and on its ozis, 



a depositor; proceiifl would immcdiAtely commeooc, 
a portion of the previously fluid mjilrrisU of tbe 
earth would tlien take a ftxed and more solid form, 
when A further compressiuu and condensation of 
the earth's body would neces&arily follow such ah 
evimt ; And ogain caUBe our planet to move slower 
in its orbit anil on its axis than previously, in 
Dorrcapondence with the progresbive Advancemeot 
of a depository process. 

Hence the same law of centrifugal force, still 
somewhat in excess, which throw out vast and 
6 til pen don sly elevated lines of granite within the 
tropics, and in the direction of the poles, would 
Also scour out enormous cavities within tlie regions 
of the poles, lift the material in the direction of the 
tropics, and so forward the work of deposition, 
until a further compression and condensation of tbe 
body of the earth would retard its motfon, the 
vuhimn of its fluids would iliminish. they would be 
checked in their motion by accumulated deposita 
rrsling upon a previously uplifted formation ; and 
progressively, as the terms on which this process 
depended had advanced in their extent and in- 
fluence, would the currents of the ocean retreat 
more from the rquator, sink grodually into the 
Polar Bnsin, and finally leave the flgnre of the dry 
land of the earth, in elevation and surface linea- 
meula, that which wc now find them to be — with 
the exception of Tokanic products, reefs of coral, 
and such like trivial anomAlies, here Aod there 
scattered upon the earth's surface. 

Flux and re-flox of tides, obviously derived from 
those oceanic currents which yet run from the 
sontb pole to the equator, thrn descend upon tbe 
north pole, re-oscend to the equator, and again 
return to their starting place at tlie sonth pole 
(running at the same time m a western direction, 
in accordance with the eastern revolutions of tbe 
globe,) would also partake of and fallow the di. 
minished speed of the currents h'om which they 
originate, and lie subdocd in polar deeps. Hence 
have the proud wavea been stayed by omniscient 
means, and on Almighty h:ind. Tliey have gone 
down into the cavitiea of tbe polar deep primarily 
scoured out far their reception, ** that they turn 
not again to cover the earth." 

At the same time, proportionally as centrifugal 
force were lessened in power^ would the concen- 
tricity uf tbe earth augment correspondingly, and 
multiply in pressure towards its centre. Hence 
those waters, that are still lifted from the poles to 
tbe equator by a centrifugal power, if tbe unslrati- 
ticd rucks lie lu continuous chains of porosity, are 
imperceptibly going partly through the body of the 
earth to the poles again, by the force of a centri- 
petal law, which plainly contribute:* so much to a 
concentric tendency. The five orders into which 
geology as a science plainly divides itself, are, 
thertfure, distinctly framed in Accordauce with an 
obviouK law iy phyiica, which gave to the under- 
most rocks the most conspicuous altitudes, and to 
the uppermost rocks an invariable depression of 
surface. Hence geology classirica itself by a moat 
ready rate. Ben Nevis is the highest mountain in 
Britain, and iberefnre dectdrs an unstratificd clasa ; 
Snowdon is the next in succession which does not 
come within this class, ond being composed uf de- 
posited and indurated mud, decides the second 
formation. Tbe Dlack Mountains in South Wales 
form a third step downwards, which cannot be 
classed along with indurated mud — being composed 
of cemented old red sandntoae. The Yorksbirt 



MAGA2INE OF SCIENCE. 



MuorUnda give a fourtli step downwards, and being 
compoted of Has, in which an excess of lime obUioi, 
they decide the great limestone order from lias to 
chalk. To thejie, as the moit depressed in eleration, 
yet the uppermost in ttraiificauon, saoceed a fifth 
order of deposits, composed of the ofT-scoarings of 
aU that had gone before — granite, indurated mad. 
cemented sand, and a concrete in which lime is the 
predominant ingredient. The scale of descent from 
the altitude of the undermost rocks to the level of 
the ujipermost order of deposita above the sea is, 
therefore, as follows : — 

Feet above ikc wtm. 

lit order. IToii »vti, prfinltp, kc, nnttmtlAed , . . .4JS8. 

Snd Snowrlon. UMluTUted rmid J,5T1 

3rd ■ Blark MauotJiinn, rcmcntrd saiidilDn* ..2.862. 

4ih Tbff YcrkiliLre MootlaDtb, Uasoi Ume- 

■lofw 1 .463. 

aih — «- Diluvial Beds, dnbrli from Ibe «bov« . . 700 

Showing most fnlly that the position of rocks, 
according to the ascending series of a depository 
procetS) exhibits the uppermost rocks as most de- 
pretsed in aUitudr, and the undermost order as the 
molt elerated. This rule, as applicable to the 
Cumberland and Westmoreland group of mountains, 
is exceedingly impressive. On emerging from a 
group of hills that mainly belong to the second 
order, where the cullivation of land is exceedingly 
limited, we suddenly come to a zone composed of 
the sandstone order and its usual accompaniments 
(which completely encircJe^ the older order,) every 
incli of which either has been or is adapted to 
cultivation ; and yet the diluviil class take a level 
in descent equally palpable and still better adapted 
to cultivation on the wltole. 

When geology as a science rests on these pre- 
niscB, subjected to the rigid evidence of facts and 
the most severe rules in physics, it follows that the 
undulations on the surface of oar globe ore maioly 
attributable to the scour of oceanic currents, and 
to tidal pulsations flowing therefrom, accordingly as 
the moon and the sun wade across the coursea of 
these Kvenil currents that cross the equator from 
pole to pole; for tides arc no more than unduUtions 
In the aet of oceanic currents. What has been 
stated, therefore, shows that deep water i^ nlmost 
always liable to dangers in navigation, which are 
exceedingly delusive, snd too often uoknown to otir 
best seamen, owing to currents, either oceanic or 
tidal, commonly setting in upon, or abutting ngsiust, 
those shores on which deep water obtains to tbeir 
?erT edge. 

In " Geology as a Scienee," page 39, it is stated 
that a "current holds its course across the Atlantic, 
and, on the eastern coast of America, abuts on 
Capo de Saint Itoqno, a point on which these 
waten. in some measure, shed themselves, running 
southward in the direction of Capo Horn, and 
northward along the north-esat coast of South 
America.*' In speak'mg about the currents of this 
cooit, Captain Fitzroy observes, in the voyages of 
the Adventure and Swagit, vol. ii., p'<ge 60, {n 
steering for Bahia de Todos Santos, " From the 
23ni to the 27th of February, 1832. we found a 
cnrrent setting ui southward, between twenty and 
thirty miles in each day. This was quite unex- 
pected by me, for I thought that we should have 
been set westward ; ' * overlooking the fact that he 
hod poised to the southward of the water-sbed 
pointed out as above; and having, therefore, passed 
the boundaries of a westward current had got into 
a southward one. Owing, probably, to a similar 
miitoke, and also an aojaaintance with the fsot en 



such a abore deep water may be taken oa a proof 
that either a current or a tide wave, or perhapo 
both of them, set in shore, and occaaioncNl the 
Theiii frigate to ran right on shore, at Cape Frio, 
on the 4th of December, 1830. Nor is it uoUkcly 
that the ChaUtnger shared a similar fate, owing to 
a corresponding mistake, to the southward of Coo* 
ception, on the western coast of South America, hi 
the night of tbc 19th of May, IBaft, from not 
sidcring that deep water may Ite in the very 
of the highest dangers, showing very distinctly 
intimately the general theory of oceanic currents, 
and their local bearings ahro, are connected with 
navigation, in warning seamen against inaidioua 
dangers to which deep water ii Ihble, aa weU u 
avoiding those shallows so common on the lines of 
cross currents. 



BOTANICAL N0T1CB8. 

CBnumed from pag9 189. ami Ktmctuded-J 

THK FKUIT OR SEBn VES8KL. 

Fmitt or pericarp* are all those cooes or 
in which ripe seeds are naturally contained. If k 
open to suffer the seeds to escape from it, the peri* 
carp is said to he Hehuctrnt, and the various pari* 
into which it divides ore called valvt* — a »eed Tt*> 
set that does not open thus is called mdehiaceni. 

Fruits maj be divided into those in which tbi 
seed and seed vessel are united together ; and tboec 
in which they ore distinct, and eaaily to be sep*- 
rated. The first clau are of neoesaity all dry uA 
indehiKxnt fruits, and are usoally called and ooo* 
sidered naked teeiU, as well as some of the othen. 
The second class is divided into dry. fleshy, polpyi 
and scaly fruits, as follows : — 

DRY rROlTS. 

In tehieh the pericarp ii united to the #eerf, 

1. CaryopstM or grain. — A single carpel or fruity 
situated above the calyx, (called tlierefore tnperior,) 
as the seeds of wheat, barley, and the other grssaeJy 
Indian com, &c. (Fig. 1.) 

2. Cremocar^. — A doable carptl, situated uodtf 
the calyx, (called tlierefore inferior,) aa is seen in 
the goose-grass ; also in the celery, parsley, carro* 
way, and all other plants, of the natural order uai- 
beUstfle. (Fig. 2.) 

In whicA the §eed it toote m tht periemrp, 

3. Vtrirlf. — A one-celled small, thin. dry. one 
or few-seeded fruit, which does not open, (Indclu- 
scent,) as in the goose-foot, Ace. (Fig. 3.) 




4. A^Mf.— A single seed, inclosed in * stony oarer* 
ing only, as in lithospermnm, and all the oommoaly 
called naked seedti of the rough-leaved plants of the 
fifth class, and those of the first order of the fov- 
tcenth. The small yellow specks on the outiiiJe ct 
a strawberry are also nuts ; and so are the nanO' 
rous carpels of the ranuncnlui, though, in these Cmi 



KmM 



MAGAZT^rE OP SCIENCR. 



197 



Old whole fniit U called ui Bt^erio. 

^ 4 & 5.) 
G/ant/.— A one or two-Boeded fruit, with ■ 
ir atony covering, wholly or parllj ioclosed 
or fleshy coat, (when c:ap-shaped called a 
rom which the fruit falls out when ripe, 
Inue, chesnat, baiel and filbert, acorn of 
(Fig». G Hl 7.) 



he. 



«l ip 



tl be obMrrvKl, Ihal altbaagb a wboU fmll 
I* cvrtato charactet, and bt called by a pftftiruUt 
nay coniiil of pirti whicli, w«r« lb«y alone. 
1» U)» frnlt to anolnvT nnnie : Uitu, a* b«foro ob- 
atrawb«rry. allbouph the whole it a pnlpy fhilt, 
«k* vr^ffo i\. anO wbicb cootala iha aecda. arc truly 
it or UiP 6lb«rt, fcc Removad ont or thair eove- 
t paricatp l> a nut; fo w*>ald be llw vtoiw vf 11)9 
^Ittia, aad oUi«n. An aeora wltbout tla rup li a cap- 
ilau tbe «ara of as apple : and many other exatn- 
b* addaoetl to abow l>iat it li nnt mrrply tbo t tnic- 
p*Tiearp llaeli*. but tlir circuntttniicrionu growth. 
of Ita envelope, vrhich mini be obaarved In 
rrnlL 

r.— A wln^d, leaf-like pericarp, of one 

the fruit nf the aah, raaplv, elm, \c. 
the ■ycflmore are commonly colled 
hanging in bunches. (Pig. 1.) 



7. Capsule. A thiocase, cootainlng many leeds 
either tufTering the seedi to escape by pores, aa in 
the poppy nnd the snap-dragon ; or splittiDg into 
raives or pircea, as in the stramonium, the tulip, 
lily, Ate. Sometimes it breaks across transversely, 
throwing off* the upper half, as in the pimpernel* 
(Kga. 2 & 3.) 

8. Fi}ihcfe. — A capanle, which opens only on one 
aide. There are mostly aereral foUii^lei together, 
but capsolea are generally solitary. The fmit of the 
pKony, monk's-hood, columbine, &c., are foIUdea. 
(Figs. A &5.) 

9. Legrumr or pod. — A long two-valred capimle, 
with one cell and many aeeds. The seeds attached 
to one of the w/wrw or the line of anion between 
tlie two Talres, aa the pod of the bean, pea, vetcb, 
lupin, <Vc. Sometimes the pod breaks acroas into 
nnmerona pieces, as in the bird'a-foot, the horse- 
shoe vetch, flu:. This form ia aometimes called a 
lomentum. (Figa. 6 & 7.) 

10. Sihyne. — A long, two-cetled, in«ny*fleedcd 
pericarp — different from the legume in having two 
rows of seeds, one attached to each suture; and 
the two valvea peeling off from the bottom upwards, 
leaving a thin paper-like membrane between them, 
aa the fruit of the stock and wallflower. (Fig. 8.) 

In a few plants, as, for example, the radish, the 
ailique does not divide, but aa ia the caae with that 
variety of the pod, called lomentum, it breaka up 
into joints. (Fig. 10.) 

11. Siiicie. This fruit differs only from the lost 
in being but little longer than it is broad, aa iu lu- 
uaria, draba, &o. (Fig. 9.) 




VLXSHY rRl-ITS. 

p."^A fruit, with its seeds placed in dry 
middle of a flcahy rind, as iu the apple, 
(Fig- 2.) 

K — Conaista of a nut, inclosed in a Hcahy 
the plum, peach, apricot, &c. (Fig. 1.) 



14. /fiji. Several nuts, inclosed in a fleshy fialyx, 
as in the rose. (Fig. 3.) T 

lb. Pppo. — Seeds numerous, surrounded with 
pulp, and attached to the inner aide of a fleshy 
shell, aa the cucumber, gourd, mejpu, capaicuio, 
&o. (Fir. i.) ^ .. 




Berry. — Seeda few, and boried in n p^lPT 
without any other covering. In the 
btiberry, cranberry, Ac, the berries arc 




solitary. In the currut, grape, barberry, &c., Ihey 
grow in clusters. In the raspberry, fiio., united tr 
each other, and to a common receptacle. (Figa. I. 

2. 3, 8c 4.)* 



iMlierry, loo. vtu fnnD«riy. by LlRDtru*. cntird a >>«rry; but i( b cl#ar tbat U retcniblra no olhet kinil oT 
iOul4 prftperly he joioed lo Ui« eaibeiv nul, und«r a <Uiltui-t name. Iti character t»elniit on*^ ^r oitir« nuta, tanted 
Je ol a Bcahy recffptacle. Mocb dlffeteoce vf opinion uxiita niiiunn hotatdtts as to tlie arraugentenl of frull^, 
■but Uine o»ce (\iitiw.llon« nte oi comparatively liltle importaacc. 



19S 



MAGAZINE OF SCIENCE. 



17- Httperidium. — Se««U few, tcated Aroand the 
ftxis of a fruit, irhtch tiu an easily-removed tpoofj 




ftCALY MLf ITi. 

19. Strobilu* or nne, is compoBed of ■ number 
of woody tcales, folding over each otbrr — under all 
of which is nut-like seed, u in the fir apple. (Figs. 
1,2, flt3.) 

^t'early (he whole of the fir tribe bear this kind of 
fruit. Thej are therefore called conifrrv or cone 
bearing. 




1 2 

The obvious purpose of seed vessels is to contain 
sod defend the seeds during cbe progress of their 
growth. They are, beaidri this, greatly conducive 
to other aacfol purposes, indcpeodcnt of the indirect 
utility they are of to us, as furnishing the variuus 
nutritiouB and (;rateful edibles, known under the 
gvoerel name of fruit. Many of them, by their 
bard or fleshy coverings, ore admirably adapted to 
protect the ripened seeds from drought or accidental 
injury. The decaying pulp of many olTera a fine 
and fruitful soil for the first efforts of germination. 
While some uf the drier kinds are so elastic, as of 
their own accord to scatter the seed far around ita 
birth-place. Only slightly shake a stinging nettle 
on tt dry autumn evening, and the elastic seed vessels 
will be seen and heard bumting open, and envelop- 
ing the place with the dost-Uke seed. The balsam, 
too — touch but its ripened capsule, it will recoil at 
your freedom, and disperse its seed to a consider* 
able distance. Tbe geranium is another instance : 
here each aecd is attached to a spring, which flies 
out and jerks it afar off. The cyclamen is yet more 
curiouo. In this beautiful little plant the stalk of 
the capflole twists op like a spring, until the seed 
tonrhes the ground ; so also one species of the tre- 
foil sows its own seed. The various ordcra of the 
tlowerlcss or cryptogomic plants are full of these 
singular contrivances, and among flowering plants 
similar instances of wisdom and care arc, on every 
aide, most abundant, though space does not permit 
even an ennmerotion of them. One other, however, 
it would be wrong not to mention, though the 
production of a distant land, as in it we see a re- 
markable instance of the care of Providence in the 
preservation, distribution, and well-being of the 
seed, when thrown into it^ usual, and, oa may be 
thought, calamitous circumstances. 

The cocoa nut contains within iiitelf suflicient 
nourishment to aid the development of its embryo, 
for a vei7 long period, without the assistance of 
extraneous agents, llie outer rind is fibrous, 
light, and matted ; and formed somewhat like thrvc 
boats joined together. Within this is a hard shell. 
with three eyes or holes to it. Then i-omes a nutty 




fleah, and in tiie oentre of tbe whole 
with a milky liquid. Suppose such 
the sea — it floats — its fibrous coat imbibe* I 
and sand — and the nut, assisted by the |^ 
tropical san, soon begins to grow. The first i 
fiign is a yellow ipongy body, formed sril 
nut. This soaks up a portion of the mill 
grow from two of the boles in tbe hard al 
run between the fibrous outer coat. Meaal 
spoDge increases — the milk diminisbee, < 
young shoot mokca its appearouoe at the th! 
By and by the roots emevge from thdr tovA 
and become changed, as all roots do when 
to disturbed water, into a long matted buac 
Abret. All this is not the work of a day, i 
month ; bat the nut is being carried by the 
of the ocean far from its native sfaore, 
length being arrested in its course by one i 
conl reeCs, with which the Eastern ocm obt 
numerOQS roots creep between the broncb) 
fragile coral— coUrct the sea wceda— bilBI 
sandy soil, and accumulate around a maa».| 
that it resists the most furious attacks of ai 
ocean. The stem abooti upwards, and witt 
visible fouudatioa for its roota, except that 
seems to have brought with it, or apparen 
of subsistence for ita broad expanding bead, 
a tree, undisturbed by the lashings of the 
the fury of the blast; a tree, too. rapid in 
abundant in produce, and from which tb 
islander derives not merely hia food, bnl 
every implement he uses, and every ti 
enjoys. 

PAPER KITES. 

EvcRY one Is acquainted with the amoM 
the paper kite, a very carious small machifl 
in its mechanism displays great in^tenuity. ' 
however it may appear astonithing that an 
this nature should form the subject of an i 
memoir : for there is one on paper lata 
" Transactions of the Academy of Berlin,' 
year 1 7^)6. But this surprise will cease wfa 
known that M. Euler was a profound geom 
at an age when most young persons see no 
the paper kite but an abject of amusement '. 
therefore it could hardly fail of being a n 
meditation. It presents indeed several 
qnestions, and which for the most part es 
treated without the higher analysis. This 
therefore may be ranked among the jufmii 
great mathematician. Wc shall not follow 
his profound calcidations ; we shall content t 
with treating the subject in a less rlforoos 
but much easier to be understood. 

To analyse this amusement, and ex^ 
takes place, let as suppose that A D rrprta 
axis of the kite, to which is attached the 00 
held at C by tbe person who 
the direction of the wind 



hodir«cUll. U 
all tbe curredfl 



MAGAZINE OF SCIENCE. 



199 



uoited in one. acting on the centre of 
tb« kitr ; mud wbicb, for tbe lake of aim- 
re fthall rapnose not to ditfer from that of 
iteclf, or to oc very near it 




B reprcient the force with which the wind, 
the kittr i« ci|M>iietl, impels iti Rurfnce in a 
BolftT direction ; draw E G perpendicular tu* 
Ke, and make E L a third proportional to 
I E G, and draw L M parallel to G F ^ 
\ represent the force with which the wind 
le lower xorface of the kite, in the perpen- 
trection, and L M will be the effort exer- 
I impalte in the direction M L or A E I), 
first observe, that by the latter the kite 

to be precipitated downwardu, but the 

B C being acute, there thence results an 
the direction B A, which coanterbalancea 
r, otherwise the kite could not support 
thja is the reason why this angle must 
By be acute. 

now make B H equal to £ L, and draw E I 
E&Iar to the horixon, and H I perpendicular 
we shall have two new forces ; one of which, 
;«et in the direction E D. and lend to throw 
I kite : but this force is annibiUted, aa welt 
er M L, by the power in C, which draws 
to the acute angle ABC. The other, 
at which tendi to moke the kite rise in a 
idirection. 

if the force E I be greater than the weight 
lie, it will be raised into the air, and If we 
that the eztreroiC)' of the cord is fixed in C, 
Bm around the point C as it rises ; but by 
io tht£ manner it must necessarily happen 
wind will fall with more obliquity on its 
. D ; so thAt there will at length be an 
n. The kite then will rise no farther, 
cord is let out ; in which case it will rise 
to itself, and as in ascending It will meet 
air and stronger wind, it will still tarn a 
kd the angle C ; or the angle C will be- 
•fttcr, and spproach more and more to a 
Cle. 

k Um mechanism by which the paper kite 
the air. It moy be rtadily seen, that if 
ttty of the wind, with the surface and weight 
, be known, as well as the constant value 
t^e A E C, the height to which it will rise 
determined. 

, which here naturally presents Itself* 

It to be the Talne of the angle A E F, 

(hat the iinall machine may rise with the 

facility ? We shall not give the analysis 

vettton, but shall only say, that if the wind 

tal. this angle must be 54^ U', or the 

h a rudder of a ship ought to make with 

that the vessel may be turned with the 

facility, rapposing the currents of water 

pel It to hATc a direction parallel to the keel. 



We shall here observe, that i( is not ibsotntely 
neceasary that the angle A E C should be invariable, 
and determined to be such, by a small cord f>ro« 
ceeding from a point of C E to another point near 
the head ; but, in this case, the point E, where this 
cord is Bttscbed to the kite, must not be the same 
as the centre of gravity of the surface of the kite, 
and the centre of gravity must be as far as poonble 
towards the centre of the tul D. It is for tlui 
reason, that a cord with hits of paper filed in it is 
added to the point D : by which means the centre 
of gravity u thrown towards that poiut. Those 
who amuse themselve with kites, were certsinly not 
conducted to this mode of construction a priori : 
the origin of this appendage must have been a desire 
to give to the small machine the appearance of a bird 
with a long tul, balancing itself in the air. Bat 
accident on this occasion has been of great atiUty ; 
for M. Euler found by a calculution. of which no 
idea can be here given, that this small tail contri- 
butes a greet deal to the elevation of the lute. 

in short, this amusement, however fiivolous it 
may appear, presents some other mechanical con- 
siderations which require a great deal of address, 
and a very intricate calculation. 

A NEW LIFE- BOAT. 
Mr. Andhkw IIrnwksbt, of Cork, a very suc- 
cessful ship bnildcr. has invented a life-boat, which 
not only combines all the improvements heretofore * 
known, but possesses original claims peculiarly its 
own. The following is the de6cri|)tion of tlie boat : — 
" The safrty-boot can be formed of any size, from 
the scalier on the Thames to the launch of a first- 
rate raan-of-woT. This at present to be alluded to 
is 33 feet to a straight rabbet, tj^ feet beam, and 
5^ feet deep, capable of conveying alxty-six passen- 
gers with a crew of sis, with every other requisite 
for future preservation after quitting the vessel. 
Tlie boat iu all its parts is perfectly elastic, except 
about three-fourths of its kcd, which is seonrcd by 
three bars or plates of copper or iron— one plate on 
each side of the keel, and one on the flat at bottom. 
These plates are of sufficient sabitaDce to give 
strength and stability, and help to act as a prepon- 
derating medium against the danger of npsetting, 
together with the precautions that are taken in the 
interior, so thst it can never upset by accident; bat 
if compelled to it by way of experiment, it will 
right itself in an instant, witltout injary to crew or 
passengers, or admitting one drop of water. The 
stem and other parts of the keel ore secured by 
thinner pUtea in joints neatly fitted one within the 
other, so as to give strength to these parts, still 
preserving tJietr elasticity, that being the grand 
principle upon which the whole structure depends. 
The timbers, which are very slight, are of oak, tarred 
and parcelled with light strong canvass, with a ca- 
sing over that of thin whalebone, token out of a 
stove or boiling pan, then served like a rope with a 
spun yam, and the oatside finished with leather or 
improved canvass sewed on ; by being secured in 
this manner they become of great strength, and are 
perfectly elastic ; and though bent any way they 
never lose their form, a most essential property, aa 
they are removed at pleasure when the boat is slowed 
awoy. The covering or skin, in pUce of plank, is 
a kind of cloth — the remit of long and arduous ap- 
plication, his sole invention. It ia of great strength 
und durability, and perfectly water-proof; for ad- 
ditional strength and security, there ore two skins 



MAGAZINE OF SCIENCE. 



of this fabrtr, gradaatia; to thicknesi from the out- 
tide inwards, bo ai to prevent any pouibility not 
oiil^ of watpf, but any damp coming tbrougb. The 
materialfi of tliia clotb arc laturated with a chemical 
proceai in the loom, which preterrei it from wet 
and the action of the atmoapberfi ; tt always pre- 
tDTTCS its pliability, ami will not beat, mildew, or 
rot. Ala proof of the perfection which thii mana- 
factarc is brought to, the inventor has cooTcrted 
aome uf the tbiuuer kind into the upjier part of 
ahoes, which is much cheaper than leather, and far 
more durable. The boat baa two pair of i^nwales, 
■eeured iha «ame ai the timberR, all tlie heada of 
which are received and steadied by the firit pair. 
iLod the other piir laahe* and fastens to the fint, 
which Iceeps the timbers in place, and perfectly 
•ecure. The coreriog, or akin , is secured to the keel, 
and bronght to the gunwales, the same as a sail laces 
Co a yard ; so that, at first yicw. it comes within the 
comprehension of a seamen, to put into form or take 
it asander. It is decked, or covered, with the same 
doth or skin : the deck laces through the centre, 
fore and aft, from stem to stern-post ; in tbu joining 
there are laps or doublings, which efTectualty exclude 
any water from getting in. Tltere is a hollow tube 
comes through the deck, which answers for a msst- 
8tep» and givt^s air to the persoas in the interior of 
the boat. The oarsmen sit on their thwarts, which 
■re of cloth through the deck, h-om which coats are 
erected, the lame as the coat of a uaat or pump, 
which are neatly fitted by plates to their bodies, and 
bnckle below their breaats. Prom the construction 
of the safety-boat it becomes portable ; the gun- 
wales and deck-snpport flip up ; of the stem and 
post, the timber ceiling, &c., all come out, and the 
skin folds together or rolls tip the keel, so that it 
oecnpies bat. little space, and can be pat together in 
a few minutes when wanted. There is no danger or 
casnalCy that the present boat, or life-boat, is liable 
to, but is gusrded against in this, and every certainty 
of saving life from the vessel lost in the ocean, as 
well as ^e vessel lost ua the rock or the shore.'* 



I 



MISCEM.ANEOUS EXPERIMENTS. 

Melt sulphur in a small iron ladle, and carry it 
into a dark room in the state of fusion. If an ounce 
or two of copper 6]ing8 be now thrown in, liffAt uiitl 

If H little nitro-muriate of gold be added to a fresh 
•olution of muriate of tin, both being much diluted 
with water, the gold will be precipitated of a purple 
color, forming that beautiful pigment called Powder 
«if Oust us. 

If a colorless solution of gsUs be added to a solo- 
tion of bismuth in nitric acid, equally colorless, a 
drovm precipitate will be produced. This is a dis- 
tinguishing charactcrittic qf this metal. 

If a solution of the green sulphste of iron be 
dropped into a nitro-mnriate of gold, the last melsl 
will be immedistely precipitated. In this state it is 
often employed in giUUng China. 

To B solution of gold add about a fourth part of 
ether; shskc them together, and wait till the fluids 
separate; the upper stratum, or ethereal gold, is 
than to be carefully poured off into another vessel. 
If any polished steel instrument orutcn»tl be dipped 
into this solution, and instantly plunged into water, 
the surftu:e will have acquired a coat of pure gold, 
being a very elegant and economical mode of pre. 
serving poluhed ateelfrom nut. 



Prepare a very dilute and colorless 
platina by dropping a small quantity of 
moriste of tliat uictat into a glau ol WBtei 
single drop of the solution of muriate of tin fa 
to this, s bright red precipitate will ba li 
produced. A more delicate tett than tidi 
metal cannot be conceived. 

If a morsel of the dried crystals of i 
sUrer (not the lunar caustic) be laid on 
burning charcoal, the metallic salt will imm 
deflagrate, throw out the most beaatifol 
lions that con be imagined, and the sui 
charcoal will be richly coated tcith mett 

Drop a piece of phospbonis about 
pea into a tumbler of hot water, and from ; 
furnished with a stop cock, force a sti 
gen gss directly upon it. Tliis will affbi 
briiiiani eoml/utttoH under xcater thi 
Imagined. 

Dissolve s few crystals of nitro-mnriato i 
shout eight times their weight of pure water 
a thin slip of charcoal in the solution, and h 
whole by means of a sand-bath. When the i 
has acquired nearly a boiling heat, the gc 
precipitate itself on the charcoal, in its i 
splendour, forming a aingalarand beautiful i 
ance. This experiment is designed to 
metaU become inaotubte^ the moment 
thevr oxygen to foreign bodies. 

Proceed as In the last ejiperiment, 
the vessel with its contents to the rays 
Here the metal will be reduced, snd the 
efTectuaUy gUt as before. This is ill) 
deojridizinp pouter of the mn'e ray*. 

If a little colorless and recently prepai 
of tin be poured into a rich green solution < 
of copper, the copper will be deprived of a^ 
of its oxygen, and a whife muriaie of cofpi 
eipitated. 

Procure some solution of sulpliste 
minimum of oxidizemcnt, by digesting 
with the common sulphate. Into thb, wl 
drop a little of the solution of pi 
and a white pntaeiate qf iron will be pi 

Pour some pure nitric acid on the bli 
manganese, and no solution will be effe 
if a little sugar be added, the tugar will 
part of the oxygen from the oxide of 
and the acid will then be enabled to 
metal. 

Expose an ounce of nitric acid for «n 
open phial, to the direct rays of the saOai 
another ounce of the same acid, that 
so exposed, into another phial. If 
black oxide of manganese be now pat ii 
ojride in the Jirgt phial will be diJttoffed, 
in the other will not be affected by the 

Dissolve some oxide of nickel in caustic 
which will produce a solution of a rii 
By exposure to the air this gradually 
purple, and lastly to b rioM. The adi 
acid will, however, convert the whole to 

When antimony is heated to whiteness^ 
rible, and in this state agitated, in coni 
air. it inflames with a sort of explosi< 
sents while burning a very singular ki 
/lame, forming what have been fore 
gentine Jlowert. 

If alcohol contains muriate of 
the property of burning with a rtd^th 



LoHnoa.— .Prinlad by n. Pkaiicii, 6. White Hone Lane, Mile End— PublUliMl by W. B«irTAui. n«>Pal»i 
CenniuiloaUoas. (whick are answered Monthly.) to ke addressed to th* Editor, at ». Coltsge Cravt, KUs 



-502 



MAGAZINE OF SCIENCE. 



CAVERN TEMrLES OF INDIA. 
Thk ftrcbitecture of tbe nnctent HmJooi appears to 
have been ilrrivcd from the baidc tdeu aa the 
Ej^ptian. TLc nio&t remarkable relics of Uiis 
people are their ftobterrsneous temples of va»t sue, 
and elaborate workatanihip, caxvetl oat of the solid 
rock at Uleplianla, Ullora, and Snlftcttr. Cornpnrc 
the cii-nvntt-d Icropica of India with the constructpd 
ones of Egypt, and tbetr reaemblance will be found 
most slrtkiiip. In both Uieae atrlca art; found close 
intercolumntalioiis, low and short architravei, and 
columns of short statue, mdtrljr sculptured. 

Tbe eaves of Elephiiuta, whidi is a stouU Island 
in the harbour of Buuibay, are most elaborated fur 
Iheir interior beauty — those of EUora for their ei- 
teriur. Ellora is a Hindoo Tillage, situated in the 
mountains, about 15 niiU'S from Aurungabad. For 
the space of nearly 2 leagues there is scarcely any- 
thing but a series of tht^se excavaleil temples, in 
whieh there are thoasands of ligares, Bp|iearlog from 
the style of Ou;ir srulpturu to have been uf undent 
Hindoo origin. At SnlMttr, an island nrsr Dom- 
hny, is an excavated temple hewn out of thi* solid 
rock, of four stories or galleries, in which there are 
300 apartmeats. Tbeao apartments have generally 
an interior rvcrss or sunetuary, and a small taiik 
for ablution. In these rercsscs, as at Elephants, 
are reprraentntlons of Hindoo drttii^s. The ground 
pagoda is 40 fret hi};h to tite noflit or flat part of 
the dome ; it is H-l fei-t long, and 46 broad. Tlte 
portieo hns fine culnmns, dccuniled with bases and 
capitals. Immediately before the entrance to the 
i;rand temple arc two colossal fttatues, 27 feet bi|:h ; 
35 pillars of an octagonnl form, about h feet dia- 
meter, support the arched roof of the temple, their 
bsics and ra[iitii]s ore comfiosecl of elephants, horscra, 
and tigers, can'cd with great rvacLness. Around 
tlie n;Ula are tno rows of cavities arranged with 
great regularity, for receiving lamps. At the far- 
tber end is an altar of a convex shape. 27 feet high, 
and 20 feet in diameter, round thii are also recrHses 
for lamps, and directly over it is a large concave 
dome, cut out of the rock. Immediately about Ibta 
grand pagoda there are aaid to be 90 ligares of idols, 
and not less than GOO within the precincts of the 
excarntiotis. 

Bat mtifnifioent as these exeavstions must be, 
they are aurpusaed by those of EHora, the general 
character of which may be learnt from the illuAtra- 
live cut, which represents a portion of them. There 
are, in and nenr this place, no less thon about 2Q 
of these caves, of which Sir C. Mallet describes 16 
in a paper inserted in the sixth volume of " The 
TruiBactions of the Asiatic Society," Of these 
we moat, of course, coofine ourselves to a geovral 
idea of their architecture. With this view we have 
selected for engraving a portion of several of thcoe 
caves — the principal in size, and most beautiful of 
which are those of Jagnath Subbo and Keylas. 

The first of these, whicti faces the y.E., is repre- 
sented at the back of the view, the long ranges of 
pillars supporting Iheceiling ; the elaborately carved 
pillars ihcmselres ; the uj'per ones sup|>ortcd by 
elephants ; the rich fringe and cornice, and the 
figures of seated Hindoos which surmount tbe cor< 
nice, like acroterions in the Greek buildings ; all 
show very considerable fckilJ and perseverance, rut 
oat, aa the whole of them arc. from the solid rork. 

Tbe large culumu, or rather the pillor to the right 
of the cut, is taken from another of these temples, 
and exhibits in a striking moaner the peculiar cha- 



racter of ancient Indian rolnrana. The capital, h miti 
be observed* is formed Uke one or more cu»hioiM| 
which it may be imagined that the weight sbovd 
has fUttencd. The shaft is regularly Buted, and tb4 
baae ia a massive block. 

The elephant appears to be no lesa an object D 
importance at Ellora than at ElephonU, wbeni ii 
is carved in relief on alt the aides of tiic 
and stands in relief on the floor. A hnfe one 
the latter kind is seen on (he floor of nnotiier 
these ravca, called Indur Snbba^ and is represcnl 
on the left of the cut ; behind which, is situated SK 
obelisk of elegant and light formation, not unlike Ihft 
Egyptian obelisk, with plain sides, sculptured wltk 
liieroglyphics, but covered with panels and muuld* 
ings, which display considerable lute. This \» 
from the cave of Keylas, and U supposed to bav 
been surmuuntcd with a lion. 

The above remarks, giving a general sketch of the 
cavern architecture uf ludia, will, it is hoprdf tM 
sufhcient to impress upon tbe mind some Idea t^ 
their peculiar characler. To enter more fully bto 
this Kubject would scarcely be compatible with 
design, and we may add scarcely useful, considrrtu| 
thai the style, however admirjihlc for a rude, ati> 
civilized people, cannot now be made subserrinl 
to oar architectural wants, nor adapt itself to liiB 
totally different rrquiremcots of oar relig^ion, nor 
is it likely to be applied to, even for the impfwe- 
ment of those architectural principles which tlta 
Greeks afterwords so fully established. 



thif^ 



ANIMAL MAGNETISM. 

f Haumeit frvm r*ftgv i6i, awf conclkidfd.^ 
Feom tlifl time of the report of the 
relative to this subject, which we have already gini* 
it remained dormant until a few years since, wWA 
It made some stir in the French capital, under lit 
auspices of Duponlet and others ; and so extno^ 
dinory were tbe facts stated, such as teeth bclRf 
extracted, and the operation of cancer being ftf* 
formed without tbe patient being aware of it, 
the faculty of medicine instituted a second 
mission of inquiry, and afterwards a 
conclusion to whldi tbey all of them came 
the whole waa a system of fraud on tbe one 
either extraordinary inscnaibilily to pain, < 
of inducing epilej>sy on the dlhcr — iha 
magnetism, if true, took effect only u[>ao 
persons, and those of weak nerves or ill st 
health, and that it proves of no benefit who 
even supposing it to be real in the cure of 
bodily or mental di»case. 

The facts insisted upon in thia country by 1 
EUintson, two years since, and the experiments 
M. DcUfontaine at present only confirm nun 
strongly the above opinion. As the subject howclfJ 
Las obtained some celebrity, we will give tv« 
abridged accounts of tlie proceedings of the praMot 
D>og;netiser. — One from the Thn^s, which has 
ceruinly shown considerable credulity, and wbidk 
mentions the bore effects ns first witnessed ^ nndtke 
other account from the luventors' Advocate, wbkk 
has taken a more philosophical view of the matter ; 
those who are furthor interested tu the subJMt, may 
read with advantagi; tbe T^mn of the fir«t week b 
August, particulariy the letter of Mr. Edwin 
who in reference to the following account 
shown with truth and sound medical 
bow even the following effects may 
natural causes, independent of animal 



kuawi 



MAGAZINE OF SCIENCE. 



203 



Tlw; niw«« of Jnly 20, mj«— '• D«rurc rnUring 
apon the uptfiiDCiit*, coodnctcd at the Hanover 
Square Kooros, it will bo as well to d^^cribe the 
•tjiftniUir, M, DelAroDtnine, himself, lie is, wo 
ftbottld say, about 40 jcafi of ago, nhout 5 feet 
If or 9. of rntbex aast«re, perhnpa thoiightfol, rost 
of coontenance. bis bair dark, worn tonicivbat 
i /a BruttiM, and bis beard, to borrow an exprcdaion 
from Dominic 'SampsoD, * prodigious/ So far 
then for tli<? lecturer — we procct^l with his eiperi- 
■mlT. About A quarter after 3 he made bit 

rftruice on a raised %ingv at tlie end of one of 
■iBftll rooms ia the building. A youth now 
■adfi bis spjiearance, of a sallow ulire compleiion, 
hut Beamingly healthy, witli dark liair oiid eye*. 
nd rather good-looking. lie wia dresMd in n 
bfark iurtout. liifiit white drill trousers, and boots^ 
and we should think falm about 17 or 18. |]e was 
thro aeaCcd in an arm-chnir, one of the cocnniOD 
•ra-chairjt bclongtog to the rooms, and the mesmp. 
rametic opervtioos commrared. Tlie operator took 
off bis left-hand glove, drew a cbair to the right of 
tW youth, tlien placed bia left thumb upon the 
•pes of his (the youth'i) ri^bt Lhumb, and two 
fingers on the flcaby part of the ball, and looked 
biin Ktriidily and fixedly in the face. It wu aboac 
two or three minutra before any yisiblc effects were 
prodaced, thouich immediately tu he commenced, a 
•ert of apaanibdic motion took pluce in the youtlt's 
tkroat, the Byropcoms indicating the presence of 
what medical writers have designated gtobujt 
Afrtcrieitt. Shortly ailer the patient seemed lost 
ft»aU ooa»cbusne», as. indeed, it was soon proved 
fce««s. Uut in the Rlr«fi into »liich he had been 
ifenmB the ordinary phenomena of sleep were not 
hJtrafrd- For example, bis neck remained rigid. 
wbUe his arms rested apparently flaccid at his sides, 
vtUle no change could be detected in the features, 
cfeept perhaps that his cheeks were a tittle more 
fvUid (if this eipreasion may be allowed, for it is 
HOC the word that expresses what we mean,) than 
vIkMi he took his seat. The somnambulism being 
Mw complete, the operator, to our horror, drove 
Kreral plna forcibly into bis head and cheeks ; but 
1^ aODinambuliat gave no indications of sensation. 
to (art, he aettmed dead, and the interest excited in 
the room was expressed in suppresaed sigbs. At 
daa period we confeis that we felt a little indignant 
at the supposed legerdemain which was being 
,.r, ..;..(_ ^,^t a very few momenta convinced n»t nf 
ice of our suspicions, and, we believe, of 
-^ .er person in the room. A phlol of con- 
cralratod ammonia, commonly called hartshorn, 
Xhm opened by M. Uclufontaine, and handed 
^ to test its strength ; and so powerful 
» one could bear it witliiu six or 
Ex^ni iuciM" (if bis nose, yet this was applied 
doeely ; in f-tct, affixed to the nostrils oi the som- 
aambuUsC; yet he gave do sign whatever of his 
■fleriag from it. and was decidedly nncon^iciuus of 
fr» prr?mce. Next some lactfer muK-hes were 
• ntX placed onder his nose, the operator 
■■-i mouth witli his hand, but neither did 
inr*" jirixluce any effect. But on M. Deliifontaiin; 
unsomnamliuliaing tiim be drew back bis 
t ui.r-i> riir- pltmi was held to his nuse. Uuinff 
. to the mngnc-tic influence, screntl 
i^ were fired from u pistol close to his 
tt, ou 1a#0j aide^, and over the crown of bis bead, 
vd tt fb« occiput, snd before his face, but he gave 
.or even moved a fibre. He was then 
awttkeucd again, and ^tsrtcd at the dis- 



chargi! of another percussion cap. Being 
tnantpulated, a perfect state of catalepsy was pro- 
duced. His arms were extended horixontally from 
the shonldcni, and his legs from the chair, and in 
this position the el ectro-m acetic current, from a 
powerful mschine, was made to peas through him, 
which shook him dreadfully, but he gave oo signa 
oi feeling. Wo forgot, in the hurry of deseiiptionr 
to say that previoos to this experiment, having 
doubts of the cataJepsis, we asked and obtained 
leave to feci the patient's pulse, but aAer a very 
cart'ful e.^aminaliun, bein^j determined to judge for 
ourselves, we could nut detect uny pulsation what- 
ever. The arm was rigid, and could not be bent. 
It resisted like the bough of a tree, and, whedier 
from fancy, ogitalion, or the magnetic fluid, we 
will not undertake to say which, we experienced a 
disagreeafilo sensadon, which no words can express, 
and gladly, therefore, left the somnambulist for our 
seat. The somtinmbulist still in the chair, the 
company were invited to teat the power of the 
electru-muguetic mscbine, but none seemed willing 
at first to subject themselves to its influence, till a 
gentleman, evidently from the country, if we might 
judge from his tine healthy looks, stepped forward 
and took the wtreii ; but he had scarcely laid bold 
of them when he gave a shout thst we shall never 
forget as long as wo live. He dcclnrcd that he waa 
so overwhelmed with the shock that be could not 
let go the wires, and therefore shouted. Tbe patient 
was next subjected to the voltaic battery. From 
this he seemed to suffer at first, but the operator 
declaring he bad not been suflicicntly magnedBcd^ 
renewed ihe fluid, when, though the battery shook 
his arms like rattles, still he seemed (piitc un- 
conscious of suffering. He wag then blind-folded 
and covered with a cloth, that be might not by any 
possibility see who approoched him, and several of 
the comp'iny thrust pins iuto his hauda and thighs, 
but he remained insensible. He was then made to 
walk, leaning on tlie arm of a gentleman who 
volunteered to support hira, when the operator 
standing at several yards distant, suddenly caused 
him to fall by a mere motion of the hand. Hiia 
experiment seemed to alarm tbe gentleman OB 
wbuee arm the somnambulist waa leaning at tiM 
time he fell, and inileid it required all hia exertions 
to kceji bis head from coming violently iu contact 
with the floor, as it was, he saved htm by tbe 
merest chance. 'When he was raised, which waa 
done by tlie operator seising him by the collar, 
the right arm, which hsd been resting for support 
ou the gentleman's arm, waa elevated and rigid, aa 
if still in the position it occupied while walking, 
while the left foot whs raised In the act of stepping 
out. Being at length unmagnetised, tbe youth 
seemed perfectly in hi^sllh, and declared that he 
did not recollect anything that bad hnppened to 
htm. We have forgotten to mention that lie waa 
directed to sing during tbe period he waa under 
magnetic influence, when be mode u low moaning 
noise, coming as it were from thu stomach, but 
which was arrested at will, by a single motion of 
tbe operator*s hand," 

The following account is given In the /nwn/onr' 
Advocate, of August 14 t — 

" Tbe o(>cr.ntionB on Thursday last, August 12, 
1S41, commenced by producing a boy abtmt eight 
years old, who is dcif and dumb, whom M. Dela- 
funtaiue proposed to place in a suite uf socnnum* 
bultam, and, while iu that (tatc, to make hiai 
sensible of sound. 



MAGAZINE OF SCIENCE. 



*' The bojr was «cat«d in «n easy chair, ond ttter 
M. DelafiinUiae had guxed nnicstly in bis face for 
s short time, wtitlst holiling the boy's hands on his, 
he commenced the mcimerit: inanipuladous. In 
the ewe of the boy. those roanipnlatiens consistrd 
In stroking down his hair, drnwing the hiind over 
his fn.ce, and pointing the ftngers to his eyes. Tlie 
boy tlien dosfd his eyen, and though for n time he 
appeared Co be astcrp, il was soon evident that there 
wiks no roesracric effect prod'iced, for mure than once 
he cried, and seemed riigbtenei). M. Delafonlnine 
then redoubled bis manipolattons ; rove from his 
seat, opposite the }toy, und strokeil his head more 
lutaiduously ; ever snd anon placing his ovn fingers 
nn the boy'5 ears, iind moving them round. The 
he»C noil Btillnesa of the room, and the sootbing 
nature of the operations, n-cre enough to induce 
sleep, and the boy ap|u-ared to be dormant. M. 
DeliifontAirio then shoutrd in his eor. The boy, 
however, K^ve no imlicotion of perception. The 
tnanipulalions nere repeated fur some time with the 
asme iU-succeas. when the boy was withdrawn. It 
VIS stated, to account for this failure, that it some- 
times requires two or three sittings lo induce the 
magnetic inflaence ; and subie(|tkent operations on 
the hny were promised. 

" The youth upon whom M. Delafontaine usually 
opcrAtfS was then introduced. He was rcco^ised 
hy some of the company as the person who had 
received the checks at the door. This circumstance 
wascertiinlyc&leulated to raise suspicion of collusion. 
" M. Delufontoine's mode of operating; with him 
waa very difff rent from that adopted with the boy 
and with the gentleman whom he subsequently 
trletl to subdue by mngnetic influence. After hold- 
ing the youth by the hand a shoit time, the ope- 
rator commenced his manipuliitions by rapidly 
moving hia hands at a short distance from the 
ptitient's face. He thru patted the youth's stomach, 
towards which he directed many of the manipu- 
lations. These operations soon produced an cITect 
on the patient, who opened and shut his montli as 
if he were purcbed ; frowned, and moved about un- 
easily. Ot'CAsioaally he put his hand to his face, 
and uttered inarticulate sounds. M. Delofontaine 
did not, however, cease hts manipulations, some 
of which from their violence hnd a rather ludicrous 
effect. He Chen produced a boule of concentrated 
ammonia, which it was proposed to hold under the 
patient's nose for three minutes, to prove that be 
must inhale during tlie lime. Some sceptical persons 
fluggcated thdC a handkerchief should be held over 
his moulh, to insure his breathing through his nos- 
trils. This, howrvcr, owing to some disturbance, 
was not effectually done, and tlus part of the ex* 
perliuent in our opinion proved nothing. A burn- 
ing brimstone match was next held under the 
patient** mouth; but as the time duiiog which tlie 
brimstone was consumed was very short, this part 
of the experiment was also unsatisfactory : breathing 
might have been easily saspended for a loniter time. 
The next pdrt of the esperimeiit consisted in stick- 
ing pins into ditfcreut parte uf the youth's face, and 
even into his no»e. The pins were left sticking in 
his face as in a pin-cnshton, but they did not draw 
blood. At one time the youth winced, when M. 
Delafontaine exclaimed in Frfuoh, ' he feels ! * and 
thereupon renewed his manipulations, to induce a 
more profound state of somnnmhuUfim. It is o 
curiosity worth noticing, that when pins huve 
been stuck into this youth by other parties blood 
hu followed the punctures, but M. UeUfoutuiuc's 



pins produced now. The patient's arms and 
were theo rigidly distended for ■ length of 
Ihoagh it wds noticed hy some medical mcD ttMC 
the limbs gradoally relaxed before they werv ui 
magnetised. 

"I'he experiment with the Toltalc battery m* 
not tried, becBuse. notwithstanding all thv 
nipulations, the patient was not in a mood favorable 
to magnetic Influence. Nothing, however, could be 
more easy thou to practice deccpttoo by prrtrndiujg 
to pass an electric current through the body 
therefore had the experiment succeeded it would 
not have tended one iota to remove oar aceptietam 
Uy a j^cQt many active nourishes of the bind 
M. Dohifontainc soccceded in restoring aoimatioti 
to the paclait, and be was led out ; some of tbe 
audience encouraging him aa be went by the 
equivocal compliment of applause. 

** Scveml gentlemen then volunteered to bo 
operated on. The first announced himself to be a 
Pclloiv of King's College, Cambridge. He 
placed in the chair. M. Delafontaine >at opposite 
tu him, and taking hold of his hands, fixed bis ey«a 
steadily on those of the patient, with the intent, at 
appeared, to overpower hira by the mystcrioas in 
fluenoe which it is known to every one if exerted 
by the human eye steadily directed. The Peltov 
of King's College, however, fixed hia eyes 
steadily on those of the operator, and was not to be 
put out of countenance. This continued for aboot 
ten minutes, without a word being spoken or a 
sound made in the room. M. Dclurontaino grt* 
dunlly itilvBOced his fixed eyes nearer and nearer to 
those of the patient, but the latter appeared to havt 
nn e'^uitl chance of magnetising Che operator. AC 
length M. Delafontaine directed the points of Ul 
fingers to the patient's eyes ; and, bringing 
close to his face, obliged him to dose the 11 
This action was continued, and it became doabtfid 
whether the mjt^etic intlurncc had not taken cfled. 
In half an hour's time the patient wax spo' 
when he immediately replied, and M. Deisi 
admitted the experiment had failed. The 
man ssid he bad experienced no effect from 
operation, only he was rather * giddy' by haviag 
the eyes of M. Delafontaine fixed so long uiKni 
him. Two other gentlemen were tried, and nmler* 
went the same gixings and manipulationi, wi' 
any better etfcct. It was then announctd t 
Delafuntftine was exhaosted, ond that no 
experiments could be made. General disuib> 
faction prevailed in the room, and a great deal of 
disputation took place among the geutlcmen on die 
platform. 

" The impression produced on us by what v» 
saw at this exhibition was decidedly unfavorable to 
the claims of animsl magnetism m a science, tf 
its pretentions be well foanded, never, surely, <lid 
truth present itself in so tuspiciuuii a form. "Ae 
fact that the youth operated on is in the employ M 
the operator, and Ihu high price diarged for al' 
inutsion, present dtrong prima facir evidence of 
cullutfion and imposture; and the immcofe beanl 
and mustachivis uf the professor of the n*"v -r^'fi'V 
are, to English eyes, the guise of charlv 



A SIMPLE CAMERA LUCIOA. 

Has recently been invented by Sir John 
late Secretary to the Royal Society of Edi 
This camera ia remarkably cheup, easily 
aud peculiarly applicable to the delineation of 




MAGAZINE OF SCIENCE. 



305 



flovers, holba, nefda, and other small objects. It 
wu erhibiled to the Edtnbargh Society of Arts, on 
MarchBth, 1S4U " Something similar," Sir John 
RobiMfi obfierrei, " wu inggested to me, some 
jtan moce, by the Ker, Mr. Taylor, of York, bat 
k had escaped my memory antU lately ; when, 
lookiog at »ome plants confined in a frame of plate 
glaas. [ was struck mixh the Tirid images of the plants 
rejected from the bright plates, at such an angle as 
permittMl nsion of objects through them. This 
Tvcalled Mr. Taylor's suggestion, and showed how 
it might be made available for copying natural 
flower* and other small objects.** 

The figure represents a piece of thin plnte-glass, 
AD S P, set upright on a drawing-board, by means 
«ff a wooden standard, A B C, in a groove in which 
the edge of the plate is retained by the wedges O 
and H. The wooden standard is not Axed to the 
dnwing-bonrd, and may be set on it iu any conve- 
Qtent position. To use this apparatus, it is placed 
ib front of the artist, with the standard A B C to- 
wards hltn ; the object to be copied 19 laid on the 
lilt-hand side of the plate, as at O ; the head of 
tibe obserrer being also a little to the left of the piU 
lar, and the eye directed towards the middle of the 
plate, as at Mt a distinct image of the object O will 
D* perceived, as if it lay on the paper at i' ; and ss, 
«l the same time, a pencil held on the right-hand 
•id* of tite pUte will be equdly visible, it may be 
f pBcd to trace the image at P. 

^-^^^ 




Some attention is required in selecting a favorable 
parition for the nppgrstas, in respect to the illnml- 
natkni of the object, and its admitting only such a 
degree of light to the paper on the right-hand side 
of the glass, as may give suRicieDt distinctness to 
the point of the pencil, by which precaution the 
reflected ima^e is seen to most advantage. 

It must be recollected, that the dtlinesUon will 
not represent the original object as beheld by direct 
vUioa by an eye placed at I, being that of a rellected 
iiiU|;eT similar to what would be seen by direct 
riaoa, if the eye had been situated at K. 



ENGRAVING. 

(Utiumed from pagg 175 ) 

Procett of Etching. — This art so pleuint and 

asyin practice, and strong in efTcct, is divided into 

¥iTf n:irts :*^1. Tbe preporntion of the copper, or 

'')Ce. 2. The transferring upon it the in- 

-I design. 3. Etching or scratching in that 

dtfign. 4. Biting in with acid, so as to render the 

design permanent. 5. Clearing and touching up 

plate previous to printing from it. 

1. 7*he preparation of the plnte, or laying upon it 

^iK elpbUig ground, tkc. Fir^t t^kc care that the 

|>lete ts perfectly cUum and bright, and without 



scratdies, otherwise take the scratches out with 
tbe humisher, and clean the plate with a leather 
and whitening. Then screw a handvice on to one 
comer or edge of it, guarding tbe foce of the plate 
with a piece of paper doubktd ; this is necessary to 
prevent tbe teeth of the vice from indenting the 
plate, and thereby injuring it. Tlien have ready 
for immediate use the twisted wax taper, the ctcbiog 
groimd, the dabber, and a sheet or two of waste 
paper, loosely folded up, so that when lighted it 
may give a large dome. Hold the plate in the left 
hand by means of the vice, the back, of tbe plate 
being downwards, snd lighting tlie paper bold It 
under tbe plate, until the whole of it is healed suf- 
ficiently and equally, in order to do which the tlame 
must be moved about. The re<|uired beat may be 
known by toming the plate up, and holding it 
slanting, suffer a drop of water from the mouth to 
fall upon it ; if this mn off in the same way as It 
does from a hot taandreas' iron, the plate is suffici- 
ently heated. This being the case, put tlie plate 
face upwards (but without removing the vice,) upon 
a quire of paper, a book, tbe table, or some other 
sobstance which will not rapidly deprive it of its 
heat. Then take the etching ground, which is sup- 
posed to have been previously tied up in a piece of 
silk, and rub it on the face of the hot plate until a 
small quantity only Is separated. The dabber !■ 
then required to Isy the ground equally all over the 
plate, which la done by a dabbing motion. Thtf 
thinner the coat of ground is, so mucli the better, 
provided it be equally difttribot«d, and completely 
cover the surface of the copper. 

While the pi'ite still rcmaius hot, tight the tapefi 
and holding the plate as at first, except that the 
face is to be downwards, suffer tbe smoke, orising 
from the taper, to spread itself over the surfkoe, 
until the latter becomes of a smoke color, or nearly 
black -| when this is the case, the plate is prepared 
ready for use, and when it has been sufferwl to get 
cold, the ground will be found sulQcienlly hard, not 
to be wiped off, and of a fine glosay aurfice. Tbta 
QlxTstian is very simple, and takes lesa time in the 
exccutiun than it does in the description. Tbe 
rapidity indeed with which it is done, will be the 
principal means of insuring Its success, for if the 
plate fihottid happen to get too cold duriog the lay- 
ing the ground previous to smoking it, the conse- 
quence will be that the smoked surface instead of 
being glossy will be dull, as if covered with smoke 
to a dry state ; this is a lign that the ground is 
burnt, and if such burning extends far over it, or is 
in an important psrt, the whole must be washed off 
with spirits of turpentine, and the process re- 
commenced. To avoid Uie possibility of this, the 
plate may be heated a second time by paper, Im- 
mediately previous to tbe amoklng. Let not. how> 
ever, the plate be too maob beatcrd in the first in- 
atancct becanse if so, the ground, when applied to 
it, will bubble up and be spoiled. Another hint to 
tlie beginner may be necessary, and that is to be 
careful whenever heating the plate a second time, 
nut to lei any particles of the burnt paper settle 
upon it, whidi is particularly apt to be the case, 
becBOse dabbing the ground (which is a resinoua 
substance,) an electrical action is produced, the 
ground is excited, and attracts from a ooDtideraUe 
distance any light floating substances. So, alao, in 
laying the plate after the operation to got cool, care 
must be taken to preserve it from dost, as every 
particle, he It tver so minute, will take up the 
ground upon which it fulls, aud occasion a speck in 



rilh 



206 



MAGAZINE OF SCIENCE. 



the etching. K an; defect should appear In the 
plate after it hia been smoked, it is in Tain to at* 
tempt to beat it, and tben dab up the same ground 
Mf^nn i when nnce fiDiahed it must remain with all 
defect*, or tUe an entire new ground muat be l^d 
on. We bftTc been tfaoa partjcnlar because much 
of the success of other parts of the process depends 
npon Ujring a good gronnd, and the student had 
much better lay twenty groonda one after the other, 
that fail in the biting in, and find all hia labour 
of drftwiiig thrown awsy by hia ground breaking 
up, when the requisite acid is afterwards poured 
npon it, and this is by no means an uncommon cir- 
oamstanoe If the ground be either ill made, or ill 
laid on. 

The next process is transferring the design to the 
ground ; this is very easy. First draw the design in- 
tended to be etched on a piece of paper, with fino 
lines, but rather a soft pencil. When finished, 
dunp the drawing slightly by wetting it for a few 
minutes between some sheets of damp paper. — 
TUus damped lay it in the proper jiosition. face 
downwards, on the ground of the plate, and putting 
a sheet of the other damp paper over it, pass it 
through the coppcr-plste printer's press with rather 
a tight pressure, not, however, too tight, lest the 
ground should be disturbed. Taking it out it will 
be foond that the greater port of the black-lead has 
left the drawing and adheres to the plate, making 
^e exact eonnterpart of the drawing, but reversed. 
If there ia not a copper-pUte press at hand, a small 
design may very easily be transferred by putting a 
riieet of firy paper npon the damp drawing, and 
nibbing it wiUi the smooth part of the ivory handle 
of a dinner knife or fork. The design being thna 
transferred, the next object is to prevent tlic hand 
from injuring it during the etching ; to do this moat 
readily cut up the cover of a book into slips, half 
an inch wide, or else fold up a piece of paper to 
form about the same thickness, and stick two of 
these slips or rolls of paper one on each side of the 
plate, then laying a thin atrip of wood serosa the 
guard or slips, the hand will rest upon these witfaottt 
danger of injuring the drawing. 

The third process is engraving or etching the 
transferrtrd design. For this purpoae take the 
etching point, and using it exactly as yon would a 
pencil, trace over all the lines of the drawing, so aa 
clearly to lay bore the lorface of iUe cojifter beneath, 
and, in fact, to scratch a minute distance into it. — 
For this a greater pressure is scarcely required than 
would be upon the pen or pencil in writing. The 
finer lines may be done with a fine point, the fuller 
linea with one thnt is blunter, though very many 
oagraven use the same point npon all occaaions — 
depending for greater delicacy or breadth of eflfeot 
t^OD the after proceaa of biting in. When the whole 
of the lines bare been tbos etched, the pUte will 
have the exact appearance of a drawing. It most 
now be examined for errors and scratches, and 
taldng a small, hue camel-hair pencil, holding a 
little Bmnawick block, properly tempered with 
spirits of turpentine, and previously poured out on 
a slab, every speck, scratch, error or defect of 
whatever nature, must be painted over with the 
black. This being done, the plate dry, and the 
guards from the edges of it removed, it will be reaJy 
for biiitig in. Aa this is the most difficult part of 
the process, and requires minute iostrucCioos, we 
most defer it till another opportunity. 



OZONE, OR THE ODOUR OF 
ELECTRTCITY. 
fPnctedingt c^' th4 Britisk JBMCciaiitm.J 
P. Db Molkths, Esq.. M.A., F.G.S., read a ptprr 
entitled " Some Rescarcheaon the Developmeoxf 
Electrical Force." l*art the 1st, An Inquiry into 
the Nature and Properties of the New Element or 
Product of Electrical Action, described by Sch6o» 
bein. Part '2d, On the Discovery of a Voltaic CoK- 
btnation of Extraordinary Energy. 

Mr. De Moleyns commenced by observing — *' W« 
are on the eve of some extraordinary discoveries in 
electro- chemical science, which will most probably 
effect an entire change in the views of chemical re- 
lations at present entertained, there can scaroety 
exist a doubt. The doctrine of subatitoHona it 
Dumas — the strong proofs of the identity of dlicoa 
and carbon — the fact of the capability ^ the saoM 
body to crystallise in forms belonging to two dlf* 
ferent systems — the observations of Scfaunbein which 
formed the gronndword of the first part of the t«b- 
ject of the presoit paper, with Tarfous other singv* 
lar results recently obtained by emint-nt pbilosi»- 
pbcrs, fully sanctioned this opinion. The intereat. 
ing cliaracter of the facts newly bronghc to ligUt, 
and the confessed inadequacy of the vanoos tb«onea 
presented to the world since the commeaoement ol 
the present century to explain or reconcile the*e 
modem rciulLs of laborious investigation, farniahed 
good ground for fresh inquiry, and encouraged ne* 
laborers to enter the field of science." Mr. Da 
Moleyns proceeded to say, that the itatemeal 
made by Professor Schbnbein at tht Glasgow Meet- 
ing, respecting the prodnction of a new element 
which he called Ozone, early attracted hia attention, 
from bis having, in the coarse of his electrical ex- 
periments, been struck by the singolarity of the pe- 
culiar odour which the power of the batteries b» 
employed produced to such a degree aa to detaralw 
him, if possible, to solve the mystery. The paper 
now read mntnincd some of the more important re- 
sults he hsd obtained. In the report alluded to, 
which was read at the Glaagow Meeting, Profesaor 
Schunbein stated thst the disengagement oi tfed 
"odorous substance'* depended, first — Upon the 
nature of the positive electrodes; second — UpM 
the chemical constitncion of the electrolytic dial \ 
and third — Upon the tein[terature of that fltiid. Bo 
added, that his experiments went to show that well- 
cleaned gold and platina were alone capable of dU- 
engsging the odoriferous principle, and thsft tha 
more easily ozidable metals, aa well as charcoal, did 
not possess that pro|>erty at all. Ttie reaolta of 
Mr. De Molcyus'a invesCigatioua fully prared: — 

1. That the diseagagesnent of the peculiar odour 
was not confined to the leas easily oxidable mtfala. 

2. That by certain arnmgements all metals, arhn 
positive electrodes, may be made to develope Clv 
odoriferous principle. 3. That certain 
metals, not acting as electrodes, wiU 
principle. 4. That charcoal fiorma no except 
this rule. 5. That all sabatanefo. whether 
line in structure or otherwise, poasesaing the 
perty of appearing luminona by friotloo, or of 
log sparks when struck, also posaesa the property of 
discharging, under such circuustancrs, the " peco- 
liar odour.** 6. That iron and nickel ilevrfripe thb 
principle much more strougty I i ^tai. 

It waa easy to account fur -'- , tn 

stating that gold and platina <-■(>;> uiwimit^j Ihr 
odour, for he applitd but one mode of cvolviug Om 



evolve 



yield- 



mm 




AGAZI] 



prrociple, naraelyf bj usin^ the fubfUnccs on which 
be esperinient«d ai poBitire electrodcA in electro- 
lytic flaids; K was, therefore, clear, that if, as he 
■taaed* cren gold and (itatina pmducMl the odour 
mhtn dean, it muat have been next to an impoui- 
bffiCy for the profrsaor to have eroWed it from oie- 
tab with varfocea more eaiily oiidable, and. therc- 
lore» in a condition to conceal rather than derelope 
•0 mbde on element. There wa« no doubt of ita 
ctolution from all the mtftali employed by the pro- 
fejaor; bat there was aa little donbt, that immrdi. 
ailclyon its disenf^gement.combmAtioa ensued with 
liie TMUiicIes of the film enreloping the Ul-clcaned 
MifMoeft of the inferior metals, and than that all 
rridcncc of iti eiiatence vanished. Mr. De Moleyoa, 
in^ the possibility of such an obgtruction to 
diten^agement of the odoor, contrived an appa- 

by which he applied friction to the source of 
the podti?e electrode, and in erery case found that 
Uw wioar was evolved more or leas strongly. Schoa- 
bcsn'e opinion that oxone was the etertro-negntive 
eAr0ient of an electrolytic compound existing not 
Ottlf in aqueooB fluids, btit also in the atmosphere, 
■Md« it t point of moch importance to aftcertain if 
itoould bo produced in dry air or m vacuo. The 
|IMlB«ar bimaelf had remarked that "problems of 
tfM bigbcit aeienlific importance would be raised, in 
flVM it ahould appear that ozone could be produced 
In dry air.'* Mr. De Moleyas accordingly devised 
lanoos cTperimrnta for the purpate uf determining 
liwt interesting queation, some of which he de< 
•cribed in his paper. He stated, that observing the 
«lenr to be prodnccfl at the poiata connecting an 
dtetro-magnetic machine with the battery, be con* 
■tnctcd an apparatoa by which magnets were made 
to nmlve within a glass cylinder, which could he 
fnbanstnf at pleasure, or filled with various gases ; 
by nich means he obtained a vacoum. and operated 
ia dry air. collecting the matters evolved over dis- 
llUed water, and by such modes he clearly proved 
Ihtt OKone could not only be produced in a dry at> 
MOphcje, but also in a vacuum, mercurial and 
eoiamon. In aeveral inxtoncea where diatilled water 
bad b««n admitted into the exhausted tube oontain- 
laig the odour, there w%a a much larger portion of 
tta tnhe unoccupied by the water than calculation 
gvv« aa the maitmam space for the rcaidual air 
titer eahoustioo ; thns proving that oxone had been 
doaecnirated, or reducetl to o substantial condition. 
Oa opening the tubes the odour was scarcely bear- 
able, and diCTuaed itself {luiclcly, causing the aamo 

-ri^nus smell aa tlint prevailing in a place 
. r. by Ughtoing. These ejcperiments, varied and 
£k«miciitly ivpeated with similar results, led Mr. De 
Mdwyna to the conclusion, which be hoped would 
atoo be entertained by the Sectipn, that the osone 
of Scbon)>cin — which he proposed to name Electro- 
f«B — fnofil l)< admitted into the list of auppoaed 
^MMflts ; that it was not, as developed by Scbiin* 
bda ftnd himself, an union of an electrolytic com. 
peond whose cation was unknown ; and that pro- 
bablji itetiHtcd jn combination in various forma of 
kiancr. which at present are considered, but which. 
in rrality. arr not cltrmentJiry. Mr. Dl* Molcyns 
added, that he was still prosecuting thf-se experiments, 
and wu <-|inle sure that the results already obtained 
would hr toUowed by a succeaaion of brilliant disco- 
wifla, proving tbe opinion at present entertained, 
OOoccming elementary substaacrs to be sadly at va- 
riance with that bcantiful simpUcity which throughout 
the untverae formed, and still forms, ihcgruunJ-work 
of the operations of the great Anthorof our exintence. 



SUGGESTIONS ON MUSICAL. STRINGS 
AND INSTRUMENTS. 

BT LKWLS GOMPKUTX, 
r To the Edttor.j 
Sir. — If the following suggestions on masical strings 
and instruments should aeem of any value, or as 
leading to any improvement upon them, I should 
be glad of their insertion in your valuable work. 

** It is known to many scientific persons, but not 
generally -known, that in strings of the same roato- 
rial and quality no perceptible difference exists in 
the height of pitch to which they can be toned i ft 
bus string, if put on a violin, could be drawn op to 
the violin pitch, and would break at the same noto 
that a violin string would if drawn tighter. If, in 
playing, either should be likely to break sooner thaa 
the other it would be the thin one, owing to the 
preasore of the bow ; and the reason why all aach 
strings wonld break on the aame note Is, that thick 
strings are like a number of thin strings joined 
together, each having its proportionate tension to 
the total, and if the whole string could be split after 
drawn up to its pitch into any namber of parts, 
each fllamrnt would be the tame note ai the whole 
string ; or if a string twice as thick as another ia to 
to be drawn np to the same note, it would require 
twice the force, though both would be equally 
stretched, that i& to say, if it require one coil roand 
tbe peg to draw a string op to a certain note, and 
two coils to draw it up to another note, another 
string of the same quality, however thick or thin, 
would do the same, and never would the thickncaa 
cause any difference. 

*' It follows, then, from this, that the lower un- 
covered strings of violins, &c., being alt of e«)uai 
lengths, the highest string is most stretched, and 
tbe lowest the least ; and this circumstance causes 
tbe higher strings to have a better tone than tho 
lower, it being impossible to stretch the lower 
strings aa much as the higher without drawing them 
up to the very same note, and if tbe lower strings 
are made still thicker, they become too stiff, with- 
out being in the least more on the stretch. An ex- 
ample of this is best shown on the double boss, the 
first string requiring a great many turns of the 
screw to draw it up to a pitch, and tbe third, though 
much thicker, very few ; and it is, consequently, 
too abrupt, not being sufflciently elastic. Bat in 
harps and piano-fortes this defect does not exist, 
as in them the length of each string is, or ought to 
be, according to the note; and though thin baas 
strings are thicker than thin treble, the former da 
not owe their bassneaa to their thioknesa, hot only 
to their length ; thongh being longer, they are im- 
pravdd by being thicker too. 

*' When a ^ood bass tone cannot be got from a 
string, whether of cat-gut, or silk, or wire, &c., it 
is fuund necesaary to toad it by covering it with 
wire, but the reason why this improves the tone 
seems not generally understood, it is chiefly that tbe 
covering adda to the weight witliout much increas- 
ing tlie strength of the string, and the additional 
weight. In order to vibrate tbe same note, most ob- 
tain the same force of spring from a thin string, aa 
an uncovered tliick string would produce from a 
tluck substajice, consequently, the thin covered 
string miut be more stretched and more elastic than 
the other, and thua produce a better tone. But 
this is only owing to the want of more elasticity in 
the strings, to which quality alone they owe their 
vibrations i if strings were perfectly elastic no co- 



MAGAZINE OF SCIENCE. 



\ 



I 



Tering wniild Uc required, and tbeu, even, very 
short itringB might produce rery low und good 
notes, lift IK Ibe case, with the vmnll steel ipringa of 
uocical boxes, end of iccordioDs, &c., which, 
though rery imall, are to ihaped u to produce 
good buM tones. 

" It seemi that the same notei from stringa of the 
•ame miterial are better in proportion as they ore 
longer, and that the length they can admit of de- 
pend! on their strength, tlieir specific gravity, and 
their elasticity. Steel and iron, then, being the 
■troDgcat and lightest mctali for strings, and being 
very dastic, are used for the treble notea of piano- 
fbitM, bot will not do so nell for the bass notes, 
becsiue the instrumcntji are too short ; the bass 
■trings are therefore made of brass, which is weaker 
and heavier ihsn steel or iron, and thos possess, io 
some degree, the qnaUtics of coTcred itrings, viz., 
of strings which have leis strength and more weighty 
and in cabinet piono-fortei even brass is too stub- 
born for its weight, therefore, its extreme boss notes 
are ]>roduc«d by corered strings. 

" lint, in order to prove the effect of covering or 
loading a string, it ini{;ht have /cad wound round 
it after it i» tuned, when it will be heard that the 
mnre lead there is the basaer will bo the note ; and 
then, if wanted to draw up the string to the original 
note (aa when unloaded), it mast be the more 
stretched to produce it. In order, however, to 
remedy this defect complained of in the third string 
of the doublu boss, covered strings hsve been used, 
but owing to want of ikill in this roanufoctare, they 
have been found to shrink and jar, and are there- 
fore discarded. A better plants by covering a small 
string with wire, and inclosing the whole in cat-gut» 
so that the string appears uncovered, but has the 
loading in the inside. It thuH seems reasonable to 
think that strings might be made of worm tpringa 
of steel, &c.. and that inch strings, though very 
short, might produce good bass notes, as more 
spring would thereby be obtoioed, and great eUsti- 
dty, which is all that is wanted for it. It Appears 
also that if such a worm spring was placed behind 
the bridge, where the tail-piece is, and the common 
String was attached to this Instead of the tail-piece, 
th« same object would be partially obtained ; but in 
tikia case it would be necessary to have a grooved 
wheel in the bridge for the string to besr on, to 
allow it to partake of the action of the spring, but 
the weight of the wheel would be some detriment, 
and the plan would not do for all the strings, as the 
bridge might then roll down. It seems, however, 
that both plans, and psrticularly the Qntt, are worth 
1 trial." 

CTohe conUMird.J 
HOTBII ON TBB MONTH OF OCTOBER. 



Wmtihtr M 



Barvmrler. 



tcnnam 

KikiwBcaoa,., 
DvaLiM 



il9\ 
51- 



29M 

»7« 



Aim in 



S-037 
3 234 



Thk cessation of sommer heat, the shortened days, 
keavy dews, and occasionally frosty nights, have, 
Aim the last month, played considerable ravages 
upon the face of nature, snd ujyon the animals of 
the wilda and waters, all indicative of the coming 
wintw. Io the early part of the month Snakes and 
Tipcn bniy tbemaelvea preparatory to their long 




sleep. The greater number of the summer 
have alrcndy gone. The hen CUaffinch, howri 
DOW leaves us ; the male sltll remaining 
country. According to the weather, so at dit 
parts of the month various winter birds re*visit 
shores. The Redwing arrives, as do 
Hooded Crows, the Wood-Pigeons, and 
the latter end of the month the Wood>C 
the Snipe. Spiders webs hang on every b 
paling ; now indeed is the only time when 
entomologist can form a good collection of 
insect— -particularly the Gossamer Spider 
through the air In his delicate car of the finest 
which we may occasionally find flouting over 
fields in myriads. Hie Squirrel and the Nuthatch 
are in the early part of the month full of 
the former in laying up his winter's at 
provender. Tht little Nuthatch is also 
running up and down the trees, and pecking 
minute insects and their eggs, which are its fi 
food. The Sea-Gall also visiLs inland parta, 

VKOXTADLK KIKCDOU. 

The decay of nature Is no where more 
spicnous than in tbe vegetable kingdom. 
trees have already lost their leaves, and others 
them covered of those beautiful tints which 
tinguish autumn, and sometimes render the 
scape scarcely less beaotifnl than in the S] 
The leaves of tbe Ash, the Horse-Cbcsnut, 
Lime, are already fallen. Those of the Si 
Chesnut, yellow ; of the Sugar-Maple, i 
of tbe common Birch, yellow and golden ; 
Weeping Birch, golden and a bright acarlet 
Marsh-Kldcr, afinepink; of tbe Sumach, apt 
red ; and of the Oak, various shades of 
orange, red, and purple. A few flowers t 
bo found even wild, and many more in the gai 
Various annuals are yet in 6ower, as are also vi 
of the Clematis tribe, and tbe Arbutus, upon 
may, at the same time, be fonnd l>oth flower* i 
fruit. The chief ornaments remaining io the 
den are various of the Michaelmas Daisies, 
Rudbeckta tribe, the Cbina-Aster. the Helianl 
or Sunflowers, and the Dahlia, little, hoi 
beyond these, remains to interest the 
Summer flowers are gone — the winter's Mos 
Lichens are not yet come to perfection; yet, 
devote some attention Io the Fangos tribe 
profit, as scarcely a wood, metadow, or hedg«. 
but contains numcroos Agarkt, Boleti. or : 
others of this interesting, bat much neglected 
of plants. 

OAHDRKING OPBaATrOHB. 

Tbe antumn, of which October may b« col 
the type, is, aa is well known, a busy waa 
the gardener, not mcrrly in gathering tbe 
of his crops, but in clearing the ground fr 
leaves, and his borders from decaying 
Other things press more immediately 
attention thiin even these neccsaary emploj 
He must sec that his greenhouses rc<]uirr o< 
pair, and according to the weather remorv 
them his plants, which he is sopposcd (o 
rongi'd in his borders dnriog the sumi 
potting such of them as may be ne<<«tsi 
autumn planting should be executed as 
month as possible. All deciduoos shrubs 
be tnuiiplanted. Evergreens may he remov«4J 
most at any time; also border flowers, nhfthtr] 
renniol or biennial, may bctronsplantrd with i 



Lowm.* — t»r»nt*(J hy D. Francii, 6, While Hofir Un». MiW Knd— PublUih*.! I>y W Dsitvaim. 1 1 
whlcb ar» ooiwared Mpalb)y,j to bt atldreeaeil ta the Ediwr.ul 21. Collage L. 



THE 



MAGAZINE OF SCIENCE 

fenzii 



SATURDAY. OCTODEH S, 1S4I. 



md. 




ISOMETRICAL PERSrECTnT:. 



in.— wo, xxvii. 




i 



210 



MAGAZINE OF SCIENCE. 



ISOMETRICAL PKRSPIXTIVE. 
iiY rnorifisuB rARi&n. 

fjhr\dif<%i /n»m the !rraN»at7<Mu tif fAr iitmbriiigt 
I'AiUmitjtburat •Suftr/y j 

*' Tb> kind of penpectivc wbicb i* tlie lubject of 
thii pNjier la much better atlaptfd to the exhibiUnn 
Af muchtnttrv, and is iireft^rable, on muiy accouiita," 
uyB Profcwwr Farisli, " to common pcmpcotive. 
It u much easier nmt nimiitrr in iti principtcjL Jt 
it, il»o» by the help of a common drnwinK tible 
und twu rulrra. incuinjiArabljr more raiy, and, con- 
iir<iu«ntly, tnorr. nccurtKe in its ap|ili(^tion ; inso- 
much, that there is nu difbcult; in girini^ bu almost 
perfertljr correct rr|)rrarnLntion nf nnj nbjrct aduiitrd 
to this peripectire, to which the artifti bai acrett, 
if he has a very limplc kuowlrdge of its phuciplca, 
Aod ft liltle pmrtice. 

"It further reprcwnts the straight lines whirU 
lie in the threes principiil diret^tinni, all on the »sme 
scale. The right angle* contained by such lines 
■re always reprenented cither by anglu of liO de- 
grees, or the supplement of 60 degrees. And this, 
thou|;h it might look hke an objection, will appear 
to be none on Uw first sight of a drnwing on these 
prineiples. by any person who has errr looked at a 
picture. For he cauDot for a moment have a doubt, 
that the angle represented ia a right angle, on 
inR|>ecUon. 

** And wc may observe rnrther, that an angle, of 
60 degrees is the easiest to druw of any angle in 
nature. It may be instsntly found by any prrson 
who hns a pair uf rompaaites, and un<lrrttands the 
first proposition of I'liirlid. l*he reprr«entation, 
Also, of rircttit and wheels, and of tlie manner in 
which they act iti one another, ia Tory simple and 
intelligible. Tlie prtnriples uf this persf>cctive, 
which, from the pecultur circumstance of its ea- 
hibitlng the lines in the three principal Jimensions 
on the namr scale, I dcnnminate ' iMumrtrical/ will 
his underatood from the following detail : — 

** Suppose a cube to be the object to be reprc- 
•cnted. The eye placed in the diagonal of tlte cube 
produced. Tlie paper on which the drawing is to 
be made to be perpendicular to tliat diagonnl, be- 
tween the eye mid the object, at a due proportional 
distance from each, nrcLirding tu the scale required. 
Let the distance of the eye, and, conscqurntly, that of 
the paper, he indcAnitely increased, so that the size 
of the abject may be inconsiderable in respect uf it. 

" It is mantfeet, thul alt the linea drawn from any 
point* nf the objnct to the eye may be considered oa 
perpendicular to the pii-ture, which becontrs, there- 
fore, a Kpeciea of orthographic projection. It is manl- 
iest, the projection will have for its outline on ct|ui- 
•ngular and ciiuiUteral hexagon, with two vertical 
Mdes, and nu angle at the top and bottom. The 
other three lines will be radii drawn from the centre 
to the lowest angle, and to the two alternate angles ; 
and all these lines itnd sides will be equal tu each 
other both in tlie objt-ct and rcprcsentution ; and if 
any other lines parallel to any of the three radii 
should c:xiiit in the object, and be reprcftrntcil in the 
picture, their reprcfientatlona will hear to one 
another, and to the rest of the sides of the cube, the 
ftame proportion which the lines represented bear to 
one another In the object. 

** If any one of them, therefore, be so taken as 
to bear any required proportion to iV« object, for 
example, 1 to 9, the others also will benr the same 
proportion to their ohjects; that is, the lines pa< 
rolld Co the three radii will be rtduced to a icale. 



** 1 omik the demonstration of thia, nnd 
othrr |^»oint#. panly for tlie sake nf i.r.vi.- ati4 
pitrlly becnuftc a geonietriciurt wtll t uliy 

in demonstrating them himtelf, frnn i*" of 

orthogmphic projection; and a perwm, wbu i» noc 
ageouictrictan, would have no interest lo rcadistc a 
demoftilrttion. 

" For the same reason, it is tmnrceaasrj Ui abiM 
that the three angles at the centre are r4|nsl to onC 
another, and each equal to 120 degrees, twice the 
angle of an Cfjuilateral triangle ; and the angle eon- 
tained between any radius ami .tide ia 60 degrees, 
the sapplcment of the above, and equal to the azigta 
of an equilateral triangle. 

" In modeU and machines, most of the hae» on 
aetoally in the three directions pamllel to the siilei 
of a cube, properly jilace d nn the object. .\nd tlte 
eye of ibe artist should be supposed to be plact4 at 
an indefinite distance, as before ciplatDcd, hi a <ttn- 
gonat of the cube produced. 

DEriKITIOMS. 

*' Tlie Ust mentiooed line may be called ibe ^iir 
of tiff At. 

" l..et a certain point be annmed In the object, 
as, for example. C, Fig. I, and be represented to 
the picture, to he called the rrffuialing puti^.— 
Throngh that point on the picture may be drawn a 
Tcrticjil line. C E, and two others, C U, CO, ooo> 
taining with it, and with one another, angles of 1X0 
degrees, to be called the iMurttrtricui lintm, to be 
distinguishrd from one nnother by the namra ofllM 
vnticnlt tbe dexter, and the itinuttr lines. Aad 
the two latter may be called by a common n am e ■ 
the horiznntai isametrieal hnes. .\ny other tinea, 
parallel to them, may be called respectively by tiie 
same names. Tbe plnnc passing through the dexter 
and vertical lines, may be called the dexter %*om»» 
trical plant ; that passing through the rcrtlcal and 
sinister lines, the aiitister planr : and that through 
tbe dexter and sinister lines, the hori^oniai plaaif^ 

" Dy the use of the following simple appnrsbo^ 
Fig. 2, the representation of these lines in the ob- 
jects may be drawn on the picture, and measured ta 
a scale, with the utmost facility, the point at the 
extremity being first found, or assomed.* Tbe po* 

" • It la imnrrpuary \n ili>wrtl»' iho lii [^.tim-.- iiilr mn 
further ihkut by iil>itvrvin|(, that II " 
U> kcfp the )iEi;Mir itondy oti whivti '■'■ 

" Ilrrc xttjulil lir ii riili't id I << 
•liiU- «'n vu* »Mlr t*f 'i 
ki*(il. tfy •nuiU ptoni> 
iminrdlntc* coiilnci ^^ 
ttmtt ilruwn llnea am i 
by meatu of m grou^ ' 
tx made to itid* au i < 
UiRii tbe IrvKttlli cf (Uo I: 
mcaoA may at pIcMurv ttr ; 
r«ptvftimi«u III iiic i>U(<7, i 
furtiwr nilcr, n. i • 
grmiV4> «bou1<) 
ami l>. are hi < 
firti ruler, Uii- t'dfcL- . 
It K, lliH *ii)« rtl in < 

Sirtldii i)( thr c<\.\<- I I 
and C. r«*t 
lb« svecnid sir 
toral iriNaglr 

K. fttf Ulc •.in.' • tu tlie ftriitu"* 

and Ix'ti) of i: iiviotd iiii#i 

and Ivtilhi, >•' ■ 

'■ ll would lie '-ciivn II nt .( Ilu" - 
tiler gtot>Y9, K &, 90 f<.Tm<'(l Ihul v l 
are In contact ultti '.!ti' ^ t^i-i ^.f 
ithduM br at r 
thfU' pri^rtT 1 1 
uf rlrrn cut •n 

pres«ntod In ¥ig. h. "I Ui<?»- lit lii^ii •• •trie* o( dttli'rT*! 
aiisa, oucrniwiuUiig li> tiU wtiveU Such ft sonss IM^^ 



i 



MAGAZINE OF SCIENCE. 



211 



of an^ ]»oint in the picture may be PuUjr 

by mauurioi;^ its three disUiicei, nontely. 

Ito porpeiHlicular diabmct: frum tbe rtgnlatiMij 

piane, (tb«t u, the horiiontal plaae 

rough tbe rcguUting point*) Hcondly, the 

ir distance of that point where the per- 

i\v meets the horizontal plane, from the re- 

ig (leiter line; and tbinlly, ufthe point where 

idictUar meets the dexter line from the 

poiflt; and then tokin^ those dijitsnees 

lii« scale, lirsc, nluni; tbe dexter line, 

kdly. aKmg the sinister line, and thirdly, alontr 

vertical line, in the picture. These three may 

led tbe dexler diitanee of the point, its nnia- 

fiancf, and its aiiifude. And it is manifest 

need nut be tnken in this order, but in any 

that may be more convenient to the artist, 

bvtng six mays iu which this opcmtioa may be 

If any point in the same isometrical plane with 
int required tu be fuuud, is already re]>re- 
in tlic picture, that point may be (uuumcil 
new neculating point, and the point required 
' bj Uking two distances ; auJ if the new as- 
tiog point is in the aame isometrical 
point, it is found by taking only one 
Aad this last simple operation will be 
ctice all that is necessary for the deter- 
moat of the points rft|uired. Thus any 
piped, or any frame work, or other object 
nftcra or lines lyini; in the isometrical direc- 
bc moat easily snd accurately exhibited 
e required. But if it be necessary lo 
lines in other directiuni, tbey will not be 
OB lh« aame scale, hut may be exhibited, if strai-^bt 
ing the extremities as above* and dniw. 
from one to the other; or sometimes 
Ij in practice by bclp of on ellipse, as 
W descril^ed. 
Jf a riirvrd line bereqmred, several points may 
nd siUhficnt to guide the artist to that degree 
d exactness which is re«)uircd. 

•' T" '*"Mi of exhibiting the re presentations of 

tny ir objects, the lines of which lie. oa 

tbr) . .. do, in the isometrical directions ; 

Hm is. |Hir*tIiel 10 the three directions of the lines 
«f tlir cube, is as has been already sbnwn ; and 
Utnrise the mode of representing any other strttight 
Sow* by finding their extremities; or curved lines, 
by hading a immber of points. 

** Win iit representing machines and models, there 

tfa n><t unlv ikunietricai lines, but also many wheels 

^1'- : -h other, to be represented. These, 

for -rr, Ue in the isometrical planes. And 

k is luriotule that the picture of a circle tu any 

•M of these planea is always an ellipse of the same 

'■^iher the plane be horizontal, dciter. or 

jet they are easily disliiii{ui»bed from 

r by tlie position in which they arc placed 

'itlr. wbich is au isoiuetriail Hue, always 

^ with tbe minor axis of the ellipse. 

* TluB will be obriou from cooiidcnag the picture 

^|,y 1..,!.. ,,f ,1.- f»^ii<^alrlc ellijwes In Vi^. 3; but tie IhirAi 
II e:)ii«r way u> iiiiikt' iimi k( Ui^t •>( Kf 
ni Ihry slaiMl. hy |iuUn)|; Dirtn III \hv 

"'- ' — . \f Die tni**T "II wbich ilw 

1 fur itttf liuoa to tw InicDd 

lie iPviTLiI ruiK'viilriL' circle* 

Ig- " 'I'fh miiibt l»e ttrnrirti ftV 

'I'lhirrfU-ly Willi *afn- 

! Knr tint (luruuku 

--1. ■iui\ mn* rii^tt Of ihu 

I (* ktiould til) luons (i* Kilimt nf |1ki 
■iii under U w Uic pti>v*a i*huvt 



of a cnbe with u circle inscribed in each of its plnnes, 
Fig. 3. and considering these circles as wheels on 
an axle. It ftirthi-r uppeurs from tlic nHturn of or- 
thographic projection^ that the m<ijor atis of the 
ellipse is to the minor axis, as the longer to the 
shorter diagonal of the rircum scribing pmruilelo- 
gram, that is, CHinoe the ahorter diagnnal divides tt 
into two equilateral trtuagles,) av tlie equate root of 
three to one ; as appears from Kiiclid, lib. I, IVop. 
-17 : and since the san of the sqniires of tbe eoo- 
ju|^te diameters in an ellipse is always the same, if 
we put «^1 for the minor axis, tbe >^'S ftir the 
mojur, and i fur the isometrical diruneter, we shall 
have 2 i^ = 1 + 3. = 4, and i « v'2. 

"Therefore the minor axis, the isometrical dia- 
meter, and the major axis, may be represrntvd re- 
Siiectively by ■^''l, ^^2, v^S, orncarly by 1,1'-1I-I2, 
]'7321 ; or mure simply, tliuugh not so nearly, by 
2S, 40. 49. 

" If in sny case it should become necessary to 
represent a circle. whi<:h docs not lie in an isome- 
trical plane, we may observe that the major axis 
will be the same in wlutever plane it lies ; and it 
will be tbe picture of tliat diameter, which is the 
intersection of the circle with the plane parallel lo 
the picture, |i8Hsiiig through id cctitrr. And the 
major axis will bear to the minor tuiis the propor- 
tion of rndius tu the sine of the in^Unition of the 
line of sight to tlie plane of tbe circle. We may 
observe further, that the duimetera of tbe elll|i*e, 
which arc to the major axis, as v'2 to -^-^3, when 
such exist, are isometrical lines. 

" .\nd the representation of every other line 
parallel, and equal tfi any diameter of the circle, 
may be exhibilt'd by drawing it equnl and psrallel 
to the corresponding diameter in the ellipse. If it 
should be desired to divide the circumference of an 
ellipse into degrees, or any oamber of parts repre- 
senting givtm divisions of the clrclu, it may be done 
by the following method : — 

" Lt;t an ellipse be drawn, Pig. Ci, and oo its 
major nxis, A, ii, a circle described, with ita cir- 
cumference divided into degree or pirts in any de- 
stivd proportion, at U, C, U, K. F, &c. from which 
points draw perpendiculars to tbe msjorAxis. They 
will cut tbe periphery uf the ellipse in curreepimd* 
ing [>oints. It would b« dirficult, however, in this 
way, to mark, with sufficient accuracy, the degrees, 
which lie near tbe extrejiiilics of the major axiv. 
But the defect mny be supplied by transfcrriug 
Uiose degrees in a similar wnVt from a graduatctk 
circle, described on the minor axis. In tlita manner 
an isometrical ellipse mny be formed into an i»oi»e- 
trical circular inetrumcnt, or an isometrical com (Miss, 
which may show bearings or measure angles on tlii: 
picture, fn the aaiue manner as a real ooropus or 
circular tnttrumcnt would do in nature. 

** It may Ik often useful to have a acale to mea- 
sure distances, not only in the isometrical direc- 
tions, but in others also. And this mny be dune by 
a aeriej of similar concentric ellipses, w la t'lg. 7, 
dividing the isometrical diontcters into equal por- 
tioHR. Tbe other diameters will be so divided as 
to serve for a scale for all Unes psruUcl to tbciii 
respectively. 

*' Thus in the isometrical squares, exhibited in 
Fig. 1, distances roeaiurcd on tiie lungr^r diii^onal, 
or ita parallels, would be measured by the dlvikioiia 
on the major axis, those depending on the shorter 
diagonal by the divisions on the minor axis. 

** To describe a cylinder lying in un isumrtriral 
ilircctiDn, the circles at ita extremities should be 



312 



MAGAZINE OF SCIENCE. 



TCpTtaentcd by the proper isometriciil ellipses, and 
two lioes tODchlng both ahoald be drawn i and In k 
siiniUr way, a cone, or fnutuoi of a cone, may be 
ducribed. A globe la represeated by a circle, whose 
radius is tho seml'tnajor axis of the eUipte repre- 
•enting a great circle. 

" It woald not be difficuU to deviie nil?s for the 
T^reseotation of many other forms vrhic-b might 
occur in objects to be represented. But the above 
cawa are suflicicnt to Include almost every thing 
which occur* in the representation of models, of 
machlDcs, of philoaophicnl instromcnts, and, indeed^ 
of almost any regular production of art. 

" To give such a repreaentation of an Ktriucan 
vase u would enable an artist to model it exactly, 
would be exceedingly easy. Let a vertical line ho 
drawn to represent the axis of the vase. Fig. d, and 
let points be taken in that ftiis, corresponding to 
the centres of the principal circles of the vase ; 
through which the horizontal isometricol lines may 
be drawn, ropresenting the radii of those circles, by 
the help of which the isomelrical ellipses represent- 
ing them are easily drown. These will become a 
complete guide to the artist. He may assist himself 
by looking at the object along the line of sight, ond 
then, if he has any skill in drawing, he will find no 
difficulty in tracing the outline from one of these Co 
the other, with suf&cient correctness. If he is un- 
skilled in the art, of course he mast be at the trouble 
of finding a larger number of ellipses to guide him. 
And in a similar manner, any solid formed by the 
revolution of a plane figure ronnd one of its sides 
may be represented.'' Other examples will be given 
on a future occasion, as well as more practical hints 
for the practice of this subject. 

NATURE OF SOILS. 

UI>rCRAL SOILS. ''• 

I. Cfajfey Soit$. — Although the word clay is 
commonly applied to any sort of earthy mass which 
cm be formed into a compact ball by kneading it 
with water, it by no means follows that every earth 
which is so characterised is the same in other 
respects. Some sorts are exceedingly sterile, whilst 
otliers are fertile, and others ore soft and ductile, 
snd more readily part with water. Again, there 
ve some sorts, such as pipe clay and fuller's earlb, 
which are but slightly cohesive; others, a^ain, are 
so extremely viscid and tenacious, as to be capable 
of being drawn out into threads; others imbibe 
water so readily, as to be easily cnt with a sharp 
instrument ; and others are so firm, bard, mid 
compact, as scarcely to admit of being softened hy 
means of water. Besides the dilTerence of clayey 
soils in these respects, there is no less diversity in 
theit colors and tftxtures. they being found of various 
shades of red, blue, yellow, and white; and of ali 
degrees of compactness and density. All fertile 
clayey soils are said to contain more or less lime in 
the state of carbonate ; and in the red, blue, or 
yellow clays, termed till, there being no lime, and, 
at tiie same time, a large proportion of iron — they 
are very sterile. In all cases, indeed, days are 
natnrally barren, from their adhering together in 
masses, except in rare seasons, when summer is ao 
divided between rain and sunshine, thot they are 
kept in a medium degree between dryness and 
moisture. It has been proposed to improve soils 
of this kind in many different woys. so as to render 
I hem fit fur the pnrpnr>rH of the gardener. <»ne of 
the mofct clfcctuul mcliiuds of improving s stiff day 



soil in lighrnras, Is repeatedly digging and stlrrmg 
it, when it is neither too wet oor too dry ; for, by 
stirring it when wet, it is more apt to be InJarBd 
than amelioracod. the working rendering it mors 
tough and oohesiTe, as is well known to brick 
makers, and in the potteries. Ridging up vaxk 
soils daring winter, to expose them to alternate 
frosts and thaws, though generally practised, is not 
always beneficial, for lliis renders some soils mors 
stifl*, while there cun be no doubt it improves others. 
From these diflerent and opposite effects having 
been locally observed, a question has arisen bs 
books as to the utility of the practice. The probloa 
can only be solred by trial ; for even the mosl 
experienced could not, on mere inapcctiun, tell 
whether a clay soil would be benefittedf or the con- 
trary, by winter ridging. Sand or coal asbas* 
ujilesa laid on in very great quantity, will in many 
cases have more tendency to bind clay soils together, 
than to loosen their texture ; on the same pniMrtpls 
that sand is employed to strengthen the cohesion «f 
mortar. By far the most effectual way of amelio- 
rating clsy soils, is that recommrniled by the es* 
perieoced Mr. Stafford, of thoroughly bumisf 
them, on the principle first brought into notiix by 
Switzer, abont a century ago. He forms a trrticb 
eight feet wide and three feet deep; filling it to (ks 
bnm with faggots and braahwood, held down by 
roots of trees and stamps, according to the qaonti^ 
of clay to be burnt. Taking advantage of lias 
weather, these materials are set on fire, and tkn 
the clay which has been dog out is piled up 
the wood. As the fire becomes stronger, more 
is thrown on tlie heap, so as to form nn em 
ment with the snrface soil. In dry weather lii 
any additional fuel will be required, though 
be oocasioaally stirred. As soon as the U 
burnt out, and the violence of the heat baa sol 
be spreads out the burnt clay, taking care 
break tbe lumps. The burning may be ooodi 
close to any crop, or tree, without danger 
clay cannot, he thinks, be burnt too much, 
advantages are, that the bunit clay in tbe prop< 
of about ono-third mixed with the other 
rendered so rich, that no manure will be 
for four or five years, and indeed it causes 
first two years rather too luxuriant a gruwtb. 
clay is rendered ss pliable as burnt clislk, 
admirably fitted for holding just the 
quantity of moisture, and no more, parti 
it be nut broken too small or palrarixod. 
the best effects in destroying wire worms, and 
Insects, as well as weeds; and "on whole qui 
he says, " where the process was performed 
ago, I have scarcely observed either slug or si 

2. Sandtf SoiU. — In soils denominated 
when the proportions of clay, loam, or other 
substances, cause them to approach nearly I 
of the sand, the heavier aorts of thia duerii 
are formed, ^lien these earthy materials 
only in srosU projiortion, the light sandy soils are 
formed ; and when there are hardly any of thtst 
earthy materials at oil. the soil is a loose blowing 
sand, usually of a while or brownish color. Ths 
proportion of Tegelnble matters, intermixed with 
the different soils of the sandy kind, are not less 
various, producing great differences of quality, (W- 
ticularly in relation to the important particoUrs of 
texture, beat, and moisture. The openness, ftff 
example, and want of adherence in such soilSi 
while allowing more readily the admission of hotf, 
and of water, permit theu alio to be carried 



MAGAZINE OF SCIENCE. 



213 



eafily and npidlj'. and hence rain and sun- 
do thrm le&a pemiHneDt benefit tbun more 
mentive sniii. Sandy soils, thtu de6dcnt io cal- 
osnouf, cUyey, and loamy materialfl, iniut be 
sndionited by kupplylng theie, by ineaoi opposite 
totboae recomaietulrd for Improriii^ clayey soils. 
Accordingly, it it recommended, when possible, to 
»pre*d over Ihem such portions of clay, or other 
TO materials, as may bo conTenicntly pro- 
Wbeo clay cannot be had, pent niHy be 
«ab«titiitcd» which la some cases will be fuond 
lo clay. But perhaps the best dresaing 
^ of this description will bo found in strong 
cump^kLs of animal and vegetable manure, mixed 
with such earths as can be procured, particularly 
day and marl. One method of improving the 
texture of such suila is the continued tread of 
.r,.,.,.,i- 5Qch as sheep, which may he foUIrd in 
'>f the garden where sand prevails, und fed 
]'i<. Their dung will at the sauti time tend 
saiuh to enrich the soil. 

3. Chalkif SuiU, — Chalky soils abound in many 
oart* of die British Empire, and ore no less various 
u quality, than we have already seen to be the cose 
r "- -'ircyand sandy iuila. By subjecting them 

heat, l-irac ib produced, from the expul«ion 
carbouic acid gas. Tbey are found of 
[< grecs of hardness and friability, end vary 
' li respect to vegetaiiou. In our endeavors 
rate ^ese kind of suila, the chief ladicatJoa 
;i!lcd will bo to supply vegetable matter, 
:iDpr(ive the teiture. In the thinner or 
-treous soiU, clay or clayey marl, and the 
rccremeata deposited in wet or swampy 
^, may be applied with benefit. On the 
• , in those whtrh are heavier, it will tend to 
liapnve their tejUure, and render them more open, 
to spread over them a quantity of sandy loam. To 
lliaa msy be added composts of various vegetable 
and anifool manure, aabea, soot, malt-dust, and the 
•JUw, according to the convenience of procuring 
Soils of this nature ore capable of being 
ed very flilTereatly, in proportion as they 
re Of less heavy. The light and moulder- 
chalky soils readily admit of the means of 
nation just pointed out ; while those which 
■ more heavy and solid quality, allow of 
vith considerable difficulty and trouble. In 
and breaking up chalky aoiU, great atttmtion 
laisite to the proper seasons : for if the digging 
deferred till a dry aeaaon, the texture will be so 
bMud and hard, that it will be found nearly im- 
picticable to work them till they are softened by 

4. Marly 5«i7s. — ^Tbese soils are less common 
porfanpB than any of the other sorts which have 
brea already noticed. They are very similar in 
property, as well as in defect, lo chalky soils, but 
•n rarely an dry and sterile, as the latter are 
MBuioaally found lo be. They are apt to be wet 
tad hmvy, and require in that cose to be similarly 

'■>r heavy clayey, and chalky soils. Similar 
1 will likewise be required, with res^Kct to 
\m- Kranuns at which marly suiUcan be worked with 
<te BOfft benefit, so as to improve their texture. 

&. Batattic and Granitic SuiU. — liosaltic soils, 
or such as occur in distncta where basalt, or whin. 
flmie. forms the underlying rock, are generally 
ItranJ to be ejtreuely fertile, on account, as it is 
Mpposed, of the carbonised materials produced 
dofiiig (he igneous or volcanic formation of the 
locks, OS uuinlaijii^d by geologists. Granitic soils, 



on the other hand, or such os occur where graolto 
or any of the rocks (except limestone,) termed 
primitive by geologists, are found underlying, 
almost uniformly exhibit sterility, owing, perhaps, 
to the wont of carbonised materials ; such rocki 
having been, as it is supposed, produced, not by 
igneous fusion, but by deposition from water. Iron 
generally abounds in both basaltic and gniuillo 
soils ; bat in the former there is fertility in spile of 
the iron, while iu the latter there coa be litUo 
doubt that it adds to the atorility. The beat mods 
of improving granitic soils, besides that of giving 
abundance of manure, is to burn them, aa recom- 
mended by Mr. Stafl'ord for stitT clays ; for by this 
mcaiLs the natural effects present ia basaltic soilv 
are saccessfnUy imitated by art. , _ 

VEGETAnLB SOILS. 

1. Loamy Soils. — The variety in the colors of 
soils which are termed loamy, seeing, in many to- 
staoces, to be produced by the union or miztuxe of 
metallic substances, iu greater ur Icsa propurtions, 
and in more close, or more hue statea of combina- 
tion, with these ; while, in other instances, it arises 
from earthy sulta, such a» sulphulc of uluiuinu. The 
colors ariaing from metallic luipregnationa of iroHr 
are, for the must part, reddish approaching tu brown, 
the color of one of the oxides of iron ; while, in the 
case of earthy salts, they are most commonly bluish, 
containing, however, some of the black oxide of 
iron, as proved by bumiog, when this is converted 
into the red oxide, and reudera the burnt tuiil more 
or less reddish, like a brick. These, however, 
though the most obvious c&iues of variety of color 
iu loaiuy soils, are not the only causes ; for they 
arc much induenced in their appearances, as well as 
in other quoliiles, by the different proportions of 
vegetable or animal matter which they contain, and 
the different states of decompoiition and decay la 
which they have been carried by lengtli of time, 
cultivation, and other means. It is said, that in 
situations where loamy soils have been but little 
disturbed, and, consequently, little changed by the 
ariiiicial additions of either animal or vegetable sub- 
aunces, and those which tbey natarally contuned 
not having advanced to the stage of perfect solutioa 
and decay, they are generally found to be of a light 
brown color, and are termed ha:et iuatns. On the 
other hand, where much culture has been employed 
for a length of time, and large applications have 
been frequently made of animal and vegetable mat- 
ters, the natural and artificial materials of these 
kinds having proceeded more nearly to the state of 
perfeet disoolntion and destruction, produce a color 
nearly ai>proaching to black; examples of wbiiJk 
are common in old gardens. Peculiar loamy soils 
are met with near the sea-coast, or on the bouka of 
large rivers communicating with it, and are, ia 
geoc-ral, very rich and fertile. Such soils are com- 
posed of a fine sort of sand, calcareous matter in a 
high state of tenuity, from the attrition or rubbing 
down of diHerent kinds of shells and other marine 
productions ; and particularly from the dissoiutloa 
of various sea-weeds and innumerable nuuinc ani- 
mals, such OS star-fish, which have perished and 
decayed there when the sea rose over that portion 
of the soil. All these materials have been gradually 
deposited, become incorporated with the earthy 
rauterials, and form a rich losmy soil. Loamy aoile 
bdug io general tenncions, or more friable and mel- 
low tli:in cUyey soiU, are consequently capable of 
being more easily improved, with leas expense, ukI 



: 



214 



MAGAZINE OF SCIENCE. 



o«n alto be wurked nt almoit 8ny seuon. The 
kindi ind quantity of manure to be givea miut de- 
|H:itd. iu ■ great measure, on tbeir natural fcrtiltt; ; 
some very rich loatna requiring little, if any, as 
over niuiuring will be mure apt to produce leaves 
and sterna than 6owerB, while loss rich lonma will 
require occuioQal drMsiog, according to tbe lorta 
of plantj cultivated. 

2. Peaiy SaiU. — Soils of this dracHption vary 
much in their quaUtieSi accordini; tu tbe other in- 
gredients incorporated with the ptnty matter, nod 
more particularly from the nature of the subsoil. — 
When the peaty matter (^atly abouudi, tliey arc 
pt^cnliarly barnrn, owing, it is probahlc, to the dde- 
tcrious lotlueDCe of the recently-discovered chemi- 
cal substance, creosote — the preservative principle 
in peat, as it is in tnr and muuiuiv -bitumen, which 
prevenls both animal and vegetable sabstsnces from 
putrefying, and which acts as a poison on both hving 
animals and vegetables, by cosgulatiug tbeir albn- 
miuoos juices. As creosote combioes with lime, 
there can be little doubt that the beneficial etfects 
which have been proved by experience to result 
,f from drfKsing peaty soils with Imie, ought to be 
8Si'ril»od to this combination neutraUztng the dcle- 
ti*fiou!i fffects of the principle, ^^'bethe^ it may be 
advi&able to mix quicklime with peal, in preparing 
com|K)st8 for American and other plants, must be 
ascertained by careful trials, bhclls, cbalk, and 
nisri, indeed, and other carbonate of lime, have 
often been foand preferable to quicklime, on the 
large scale, in such soils. 



CASTING IIRONZE STATUES. 
Ama the artist has finished the model of the fall 
lixe, he takes a mould of it in stucco ; the separate 
picvei of this mould roust be of such a aiae and 
form, as to port freviy from the model. 

Tbe outside of this mould is now smoothed down, 
and that they may the more easily be put in thetr 
jirojicr plnccit again, each part hss a number cut an 
the back of it; these ore now oiled, and a cast is 
taken off the outside of them ; this Urge outer case 
is made tu part asunder in two pieces, if the figure is 
not very large ; the numbers cut in the buck of each 
amull piece, will have mode a corrcspondioft mark 
on the inside of the large outer case ; this enables 
the artist to place tbe parts in the outer esse as be 
takes them from the model. 

Let us suppose tltat the whole parts of the mould 
are phit'cd in the two outer cases as they ought to 
be, 50 that if the two were put together, thpy would 
be a mould fit to cast a solid figure ; but this Is not 
what in wtuitetl, and a mould of stucco is only fitted 
for casting wax or stucco figures, as it will not stand 
hot metsi ; therefure, the artist lines the two half 
xnouldB with a sheet of wax of the thickness that he 
wants the metal to be, taking care that the wax is 
pressed properly into the mould that it may have n 
complete impression of it ; the edges of each mould 
arc smoothed that they may fit one another. 

The whole » now filled with loam to form the 
core, having proper veiitG left to convey out the gas 
tltat may ansc from thn hcatrd rortal acting on the 
cure. The core is also supported by having bars of 
iron laid into it, bent to fit tlie fono of the figure ; 
the two halves arc now joined, and the whole set on 
eud ; the outer case is now taken off from the 
mould, and each of the smaller pieces removed from 
the wax. Corrections are then made by the artist 
ou this wax figure. 






Long prncilei of wax are attarbetl to all the porta 
of the figure, from which the air will requicr to ht 
taken ; those are connected with tbe renta. 

The founder now commences by coaling over the 
whole with what he intends to be the iimei stufoec 
of his mould, which is groerally clay-Wiitcr, aail 
powdered charcoal; loam is applied after the hnt 
coat is dry, and increased in thickness until rnoo^ 
has been applied; the whole ie> now built 
with brick, and strongly bound witii sorew. 
to prevent tbe mould bursting with the w 
the metal. 

The whole is now dried with small fim, plaoMi 
round and below it ; after a short tiuie. these fires 
are increased to melt out the wax, nhich rnos Into^ 
vessels placed to receive it. Wlu-n the was U 
out, the fires are increased until the mould In hnint 
to redness ; it now requires to be treated the aanft 
as any other luam mould, that w. put lata a pit ami 
the sand rammed hard all round it tu prevent tli* 
possibility of the metal either bursting or olbinrwio* 
making its escape from the mould j tlk« core mart 
aim be well secured in its place, to prevent il fruoi 
shiftmg or beine bunyed up by the fluid lurtal. 

After tbe metal has been run into the uiuuld ami 
cooled, the outer materials of the mould are l*km 
off, and the surface of the figure clenoMl. the arutt 
resumes his labour by cutting ulf the gates, venta, 
Pcc.f making good any deticiencios by indrntiOb 
pinning, and pairing away any roui^DBas until U ■ 
complete iu uU its parts. 

TUE INFLUENCE OF FERRO-CYANATB 
OF POTASH ON IODIDE OF SILVER. 
Mb. R. liuNT, Uie author of this paper, Iwing ea- 
gaged in experiments on that variety of photogrs* 
phic drawing which is formed by the octlon of the 
bydriodic suits on the darkened diluri'l' • ' 
with a view to the removal of the iodide, : 
the process, from the pajier. was leil t 
some peculiar changes pniduced by the 
influeaces of light and tbe ferro-oyanate of 
Ho found that the ordinary photographic paper, 
allowed to darken in sunshine, and then &lkf;Mly 
acted on by any hydriodic salt, and wail 
dry, with a solution of the ferro-ryanate 
became extremely sensitive to light, chaiiL: pt. " -m 
a light brown to a fuU black by a nomcut't cxpo- 
aun: to sunshine. Following out thia result, it «il 
discovered that perfectly pure iodide of eiWer wsa 
acted on with even greater rapidity, and thur ii be- 
came easy to form an exquisitely sensitr 
graphic psper. l*he method recomineTi 
following : — Highly gtaxed letter paper la 
over with a solution of one dram of niirale of 
to an ounce of distilled water ; it b quickly 
and a secQnd time washed with tbe same solutioBkl 
It is then, when dry, placed for a minute iu a suk* 
tion of one dram of the hydrindate tif jtotaab in sU 
ounces of water ; and, being placed on a am«ol)k 
board, gently washed by idlowing pure water to 
flow over it, and dried in the dark at i:ommun ICB* 
peratares. Papers thus prepiired r ■■ '- ' -•' '" 
any leni^th of time, and are atnny n 
far more sensitive than any knov< 
preparation, excepting the eulatype. wl 
equals, hy simply washing it nver with 
formed of one dram of the (< r. 
to an ounce of water. Thrac ; 
with thi; fcrro-cyanate, and tlnni 
tliis dry slulG they euro absolutely 



MAGAZINE OF SCIENCE. 



215 



mm.y a< iiny moment be rendered sensitive by 
V 'hem with a littlr cold water. Tbe 

apcf I quite insenaiblc by being waabed 

wiUi wi< mOotc hydriodic solution, and from 
|)botoi;ni]ilt thiu fixed, mnny copies may be 
ikVB. Thr author ibcu described tiie action of 
m on this ]in.*)>aration, and (minted out 
htt the g^reatcst effect was produced by the least 
rnys ; but that all tbe rays, excepting 
fr rtd, acted with considerable energy, 
imprfaied apoclrum wag. tn all ates, distinctly 
~ from end Co end ; and it hu found that the 
of aaperpo^ed media left a corresponding tint 
tbe pNper. but. unfortunately, as the paper 
tbe colors faded. These result* bring nearer 
probability of being enabled to produce eventn- 
photographic pictures in their native colors. 
m formed on these papers were all sur- 
y a marked space, which was protected 
uBoence of the dispened light, eibibiting 
r proof of the fact notic<?d before, by Sir 
Herschel nud the author, that a class of raye 
bmng pecolior negative properties emtnate from 
lkr«dge> of the sun. Some spectra and numerous 
of these drawings were exhibited.— 
^ lAe lirtluh Auociahon, 




WkU vu<. 



RECENT VOLTAIC COMBINATIONS. 

ffltoMwafMH ^Mr. Iff Mvlejmi't Paper partly interitd in 

mtrtasl \umhfr.) 

thor stated that from Uic period of the great 
of Volta ap to the period of the grand 
ement of Sir Humphrey Davy lu the decom- 
posilion of the alkalies, but little improvement hnd 
Wen riT.'rted in the development of the powers of 
■ battery — at Ihot period, great effects 
produced by gigantic means, which re- 
paired on enormous eipeuditurci and therefore could 
be gol up by public institutions. Since the 
alluded to. tbebnttery had undergone variooi 
t iiiipruveuieutj in tbe handcof W'ollaston, 
d Faraday, which hud the effect of dimi- 
ita sise oud e.Tpeuse materially, without 
the power. In 1H2H and ltt2ll Itccquerel, 
Qguiihcd French chemist, discovered the 
(y of keeping up the energy of the combin- 
• long period, by tbe interjinsition of a 
of sulphate of lime, or thin animal 
and two fluids, namely, solution of sul- 
xinc, next the tine, and of nitrate of copper, 
le copper. Previously, the power of the 
always diminished after a very few minutes, 
a serious impediment to tbe progri'ss of 
by means of electridty ; it was therefore 
•tep to have obtained a means of preaerting 
for some hours. In our country, Pro- 
Daniel constructed, in the year 1836, what 
the " Constant Battery," in whicli a din- 
was also adopted, anil two solutions of 
: arid and sulphate of copper. Mullins's 
OBtaining Battery," in which on alkaline solution 
Hxt the line was used instead of an acid, and 
ritfmie or sulphate of copper in solution next the 
Bl^cr, (tlius dispensing with acids attogelhcr.) 
iMMMcd still greater capability of preserving or 
MUlDing the electric energy, and had been made 
1^ so for months ; but none of these combioa- 
bu preacnted the grand desideratum of great 
ia suLoll spoce. Grove's discovery succeeded 
la 1838, but although this battery possesses 
r, it iud tobe charged with oonccDtratcd 




acids, which ia their subseqacot decora position 
produced fumes so noxious as to render it extremely 
dangerous if hrooght into general nee ; benidcs, the 
battery was not a sustaining one. Still Mr. Grove 
had Diade a great stride in the development of tbe 
electric force, and deserved much praise. Tbe 
author then referred to bis late invention of the 
** Calorific Sustmning Battery," by which the eoer- 
gies of electricity might now be applied to roriou 
useful and important purposes, for a vast power 
could be produced within so small a compass hs to 
afford B certainty of the obtainment of lufllcient 
force for locomotion, ftc. The author stated, that 
witli a series of three paira of plates of six s^iuarc 
inches of surface, six cubic inches of tbe mixed 
gosea might be produced per minute, and clectro- 
magncti charged In proportion : indeed, the power 
of Ihe magnets, when so chargetl, was nnequalled, 
and a great advantage was. that the power was ob- 
tained by extremely simple and economical means, 
ood the battery could be made to retain its energies 
undiminished for any period required, — while there 
was a perfect freedom from noxious fumes or any 
otiier disadvantage. One cause of the iramenae 
force developed, was, that tbe author bod obtained 
by hia combination the sum of the affinities in place 
of their difference. He added, that he saw a period 
rapidly approaching when our views of chemical 
relatiuna must undergo a great change, for it was 
impossible to reconcile many of the latest disco- 
veries—including his own-— witli any of the theories 
at present in fashioa in this country. It appeared 
quite clear to liim, as it did to many continental 
men of science, that electricity most be looked 
upon as the origin of all chemical action, and not 
chemical action of electrical. The author concluded. 
by stating that he was still engaged in effecting 
further improvements in bia invention, which would, 
he hoped, render the iostnuneat more generally 
useful. 

MEDICiVL RECEIPTS, &c. 

J^akt^M Patent PilU. — Made with colorynth, 
sulphate of potasa, and sulphate of peroxide of 
mercury. 

Lipsalve. — Pat 8 ounces of good olive oil into • 
wide-mouthed bottle, and 2 ounces of the bloomy 
parts of alkanct root ; stop the bottle, and set it in 
the heat of the sun till it be of a fine crimson color ; 
strain the oil clear into a pipkin with 3 ounces each 
of fine white wax, and fresh well-cleuncd mitttun or 
lamb suet ; melt the whole by a alow tire, and when 
taken off add -10 drops of oil of rhodium or lavender, 
and pour it into small puis. 

IT7ii7e Lipualre is made the some way by leaving 
out the alkanet root. 

Liquid Soap. — Take 2 pounds of the best Alicant 
or Joppaaoap, scrape it very fine, and put it into a 
gallon of tbe best spirits of wine, with half an ounce 
of good rosemary or lavender oil. Set the bottle in 
the heat of the sun for ten or twelve days, taking it 
in at night, and ahaking it till the soap is difsnlved ; 
then filter through cotton. If properly made it will 
be transparent, and of the color of sack. The older 
the Boap the better. Imitated by nsing common 
tallow soap and malt brandy, and is not so strong 
by half as the genuine. 

Afaithetc^s injection for fistula, piles, ^. is a 
nostrum composed of tincture of cantbaridea diluted 
with water. In many coses it may produce trouble- 
some and even dangerous irritatioa. ^ 



216 



MAGAZINE OF SCIENCE. 



' Matthetp'M Pilh. — A DOBtram compoBcd of equil 
psrti of blAck helleborp root, white hellebore root, 
Hquorii^ root, turmeric, opium, paritieil Castile 
•oap, Aod ijrup of ufTron, made Into a uus with 
oil of tarpentine, and divided into five-g^run pllU. 

MagHctia Water, or Aerated MatpUMia Water, 
b made hj roiling 3 drami of carbonate of mag- 
neaia with 1 gallon of water, and impregoatiDg It 
with ten timea its volume of carbonic acid gas hy 
muns of a fordng pump, or soda water apparatui, 
or it may be made extemponLoeoafilj like Boda 
water. It is a good antacid, and on excellent vehi- 
cle for antacid and lithontriptic medicines. 

Jfori Jen'f AntitcorbuHc Dro/Jf.— A solution of 
bichloride of mercury in the infusion of gentian, 
with a little spirit of wine to make it keep. 

MarshaiVfi Certite.—Ttkt & ounces of palm oil, 
I ounce of chloride of mercury, 2 ounees of nitrate 
of mercury, and \ ao ounce of acetate of lead ; mix 
and form a cerate. It is a good stimalant for in- 
dolent ulcori. 

Mineral Mttallic Cement, — An amalgam of tin- 
foil and quicksilver combined with iron tilings finely 
levigaled, for filling dpcayed teeth. 

MorisQfCs PiUt. — There are two aorta of these 
pilLi. No. 1, and No. 2. The first are the imallcat 
and darkest colored, and are composed of bitartrate 
of potass, aloes, and asaafoetdia ; the second arc 
composed of the same ingredient, with the addition 
of gambi^e. Moriaoa says wo cannot purge too 
much 1 1 1 

J}r. MorrittytC* PilU.—~K nostrum in Imitation 
of Marimn't PilU. 

Mtftley'r PHiM.'—k nottnim composed of rhubarb 
and ginger, made into a mass with conserre or mu- 
dlage. 

JVbrw'* Dropi. — A nostrum prepared by dia- 
solvlng potassio- tartrate of antimony in rectified 
spirit, disguised with some vegetable coloring mat- 
ter. Dr. Paris found no indirations of opium. 

A''or/on'# Drops. — -A nostrum composed of bichlo* 
ride of mercuryt disguised like the preceding. 

Xoujfiettr'a Receipt for Worms. — The following 
is the celebrated remedy, the receipt of which was 

Jmrchascd from Madame Nouffleur, by Louis XV., 
or a large sum of money, tnd published. Powder 
yerj finely, for one dose, 3 drams of the male fern, 
AepUlium JiUx maa, and after the patient has been 
prepared the previous night by an emollient cljFSter, 
and a supper of panada, tlus is to be taken early in 
the morning, fasting : two hours after a bolus is to 
given, mode of 12 grains each of chloride of mercury 
and scammony, and 5 grains of gamboge. This, as 
Dr. Good remarks, will probably kill <»tber ibe 
tape-worm or the patient I 

Pvarl JTfl/er.— Put \ ponnd of the belt Spanish 
oil soap, cut or scraped very fine, into a gallon of 
boiling soft water; stir the whole well, and let it 
stand till culd ; then add a quart of rectified spirit 
of wine, and \ ounce of oil of rosemary, and mix it 
thoroughly. It is reported excellent as a cosmetic, 
and for removing freckles. 

Pierre Ihrine, — A nostrum ased for tooth-achop 
composed of 3 ounces of burnt alum, mixed with 
I ounce of solution of ammonia, and holored with 
20 grains of vermiUion. 

Koche'a Emftrtication for Hooping •emigh. — S. 
nostrum, the basis of which is olive otl, with which 
is mixed, as stimulant ingredients, half the quantity 
of oil of amber, and of cloves. 



Rmuaemi'$ Drvpe.^^Take 12 ounces of wbtte 
honey, 3 pints of hot water, disaoWe the hoo^ ill 
the water, put the mixture in a matrass, and act it 
in a warm pUce. As soon as the fermentation be< 
gins, add 4 oanoes of opiam dissolved in 12 ounoos 
of water. Ferment for a month in a warm pi 
then strain and fitter the liquor ; evaporate till there 
remains only 10 ounces, Btrtin again, and add 4) 
ounces of alcohol. 

RmrlantPM CephattPttm la dlignlted ether. 

PoiptaniTt Kaiydor is mode by bruising I omm 
of blanched bitter almonds with b grains of bichlo- 
ride of mercury, and adding by degrees t puit of 
rose.water. triturating well, and straining throogh 
fine muslin. It ta by no means a safe prepsntiaii. 

Rowland'M Macauar Oil is made by boiling aay 
rancid oil with onions or garlic to take of the bod 
smell, and scenting with oil of rosea, and ooloriqi 
while warm witli alkanet root. 

Reymolds'M Specific for Qout and RAemmatitmi^ 
Th'iB, like many other nostmma, was copied from a 
formula published by Want. Take 8 ounces oStha 
fresh bulb of colchicum, IC onnces of sherry wtui 
macerate for eight or ten daya in a gentle heit. 
Color it with syrup of poppies, and add nua to 
flavor it. Reynolds is said to hare killed himiclf 
by takini; an over-dose of it. 

Rymer'g Cardiac lecture. — .K nostrum which ii 
composed, according to Dr. Paris, of an iofusioajl 
capdcnm^ camphor, cardamom seeds, rii ' 
aloci, and castor in proof spirit, with ■ wtrj 
quantity of sulphuric acid. 

PoweiFs Diuretic Dropt are made with 4 
of oil juniper in 1 pint of spirit of wioe. 

Saline Draught. — A common popular 
tion. Take I scruple of bicarbonate of 
grains of citric or tartaric acid, or i ounce 
juice, 2 drama of cinnamon water, 8 ounces of 
water, 1 dram of synip of orange ; nix as • 
frigernnt. 

ScotVi PilU. — A nostrum composed of i 
of extract of aloes, and 1 ounce each of 
and powder of jalap ; make a masp of tincti 
senna, and divide into four-groin piUf . 

Seidlitx Potrders.—Ttke 2 drams oT 
tartrate of sods, and 2 scruples of eesqn: 
of soda ; mix, and dissolve in 4 plo^ of 90il 
Then dissolve 35 grains of tartaric acid in 
ntfficiat of water, and odd this to the form 
tion. It must be draok in a state of cffcrv 
It is a mild cooling purgative; but il is not at 
Like the genuine Seidlitx Water. 

Seidlii: Water.— Take 204 drams of water, artJo- 
Uted in the usual apparatus, with thrice its v 
of carbonic acid gas, about 2 drains of salpl 
magnesia. 18 grains of hydrochlorate of i 
dissolve, and bottle for use. If it be wonted 
double the quantity of the sulphate and bydroctdo- 
rate of magnesia. 

Seltser Water. — Take 204 onnoes of water iffl- 
pregnated by the usual apparatus vrith carbonic uU 
gOB, and dissolve in it 4 grains of carbonate of sods, 
2 grains of carbooate of magnesia, and 20 gnini oT 
chloride of sodium. It is a mild purgative. 

Singleton'a Bye Salve, or Golden Ointmest. U* 
prepared with equal quanlitiea of orptment (sesii>i* 
sulphuret of arsenic) and prepared lord. 

Speediman'f Piils are composed of aloes 
and rhabarb, with the extract and Tolotlla oil 
chamomile. 



Loiwos,— Prlated hv I>. Puncii. 6. While ttont Lane. Mils End— PablUhed hy W. BsirTAm. 11 . Patemasiet K«« 
fidinburgb, J. Mniias.— Clas{ow, I>. Sum lod J. JiAOXi8.-UvCTvoo1. J. Vuaxt. 



21S 



MAGA;;rNE OF SCrKNCE. 



BRAMAirS UYDKOSTATIC PRKSS, 

Tnis taost valunble Instrument possesses s pon-rr 
which no other preM cnn approach to, murh leAt 
equal. Thr power iiiiiecd may be considt^red with- 
out liiiiic. eioi-pt the poiitive fitren);th and tenacity 
oF Tnateriala ; and ta the whole ii of »*A'u\ iron, that 
will, in prapticc, ac-arccly form sn exception. The 
pre»d in repre^tented in lection in lh« nits apper- 
taiutii^ to it ; where No. 1^ shows the longitudinal 
wrtion ; and No. 2, an enlarged view of the working 
pAftfi. It maybe thus described, A A B, Fig. I, 
is the frsme, (ns the view is but a section, it is to 
he understood thot there urc four supports, and that 
the top and bottom of the press are of sufficit-nt 
width to hold the habstanre to he pressed), consist- 
ing of a piece of cast-iron, C C, and a top piece of 
cnst iron, B, the two bctni; united hy the wroughtr 
iron bolts. A, A, whirh mu»t hare sothcient atreni^th 
to resist the whole force of the press, the pressure 
being produced between the undiT fcarfaee of B, 
and the upfwr surface of au iron table, or follower, 
£; F is a strung mctiUUc cylinder, in which the 
rammer, or piston, D, moves. To the upper part 
of tltiH piston, the iron table, £. is fixed, by the 
motion of which upwards, the pressure is eonima- 
nictttod to the nrtirles placed upOD it; L represents 
a cifllern contninlng water ; within this cistern is 
fixed .1 smaU forring, or injecting pomp, of which 
R in the pieton-rod, and H the IcTer by which it is 
worked, a contrivance being introduced for keeping 
the piftton-rod vertical during the working : it con- 
iisls of a guide, formed at the lop. of the same 
standard, K, which supports the fulrnim, or centre 
pin, P, of the lever, H ; the rod, N, which is part 
of the piston rod, slides through tbe socket; the 
piiil, O, of the rod is msde open, to admit the lever 
to p<us througlr it, a link being applied to unite the 
levtr to tho rod; I Is a counterbalance for tbe 
weight of tbe lever. Pig. 2 is a se^^on of the 
pump, on a Urger scale, Co show ila interior struc- 
ture, R repreaeDling the lower extremity of the 
piston rod ; it is surrounded by a collar of leather, 
S, which is retnined in its place by a tube, or per- 
fornted screw, K, which admits the pnssagc of the 
piston rod, H, but which screws the two-cupped 
leathers nith tbe metal ring, wfaicli is interposed 
between tht;m, close down to a shoulder, in the 
body of tbe injecting pump, nnd thus renders the 
junction between the inje«-ting pistoo, H, and itA 
cylinder, water-tight : the upper part of the screw, 
R, is excavnted, to form a rrcepLuoIe for oil ; M M 
is the barrel, or chamber of the pump, in which 
the piston-rod does not fit ; bat the collar of leather, 
S, closely embracing the rod, will have the sstne 
effect of enlarging or diminishing the capacity of 
the chamber when the md is moved up and down. 
In tho bottom of tbe chamber is a suction vulve. 
N, which allows the water to enter into the barrel 
from the cistern, but wilt not permit it to return in 
the same direction ; it is fitted into the upper part 
of « lube, N, which i* screwed into the lower end 
of the barrel : the vslve itself consists of a metallic 
rod, at one end of which is s knob turned conical 
next the stem, so as accurately to fit the conical 
face of the hole Into which it is put ; the tjuled is 
fiUid on one side, so that it does not entirely fill 
the cylindrical hole which it occupies, by which 
mcQna a passage is afforded for water when the head 
of the vaire ia raised. A valve of a similar nature 
is placed at T, iii the upper part of the pump, and 
bviii^ ia the pas^sge which cooveys Uic water from 



the pump, and Ihrongh the copper pipe* B. to tha 
cylinder, F, it allows thci water to paw from chv 
pump to tlie cylinder, and preveuta its rrtuniitig- 
At K, Fig. 2, is a aafay-valve, which is loaded by 
a ate^yard and weight, as shown at K, Fig. 1 : thb 
keep! the valvs shut in the ordinary cutirae of 
working ; bat if the presiure should becimie lo 
great as to endanger the bursting of tbe pipes, die 
valve riles, and the water escapes. At I is a acic* 
plug, or vaIre, at which the water is discharged* 
when the press is to be relieved. When scrrww! 
tight, its conical end, or point, is force^l into i 
corresponding socket, and prevents the escape of 
the water ; but. on turning the screw bark, lite 
water is pt^rmiitcd lo flow back into the cistwa. 
Tbe real situation of this discharging valve h »bowi 
in Fig. 1, at S. The cylinder, D, ia •urromidrd by 
a collar of leather at Q () : the leather is fiwai^ 
as shown in Fip. 2, being turned up to form i 
double cup, BO that it resembles thf* -■■" ■■' ■ ■'^'f 
sleeve. \\ hen in its place, it is k 
the copper ring, P. entering the en 
or fold, of the leather. This ring boa a loiigwcat 
in a recess formed within the cylinder, F. TU 
leather is kept du^fn by a brass, or bcll-metal, riiif. 
Y, which is received into a recess forwed roaol 
within the cylinder, u shown in Fig. 2. Tb* 
tenor aperture of this ring is adapted to recei 
cylinder, D, aud thns the leather becomes con 
in a celi, with the edge of tbe interior fold appllBi 
to the cylinder, D, whilst the edge of tbe ostar 
fold is in cootnet with the interior surface of 
cylinder, F. In this aiiuation the pressure ol^ 
water, acting between the folds of tbe 1 
forces itf cd^fs into close contact with both,' 
makes a tight fitting round the cylinder, aud 
pressure is increased, tbe leather is apphed 
clo^^ely, BO as to prevent leakage under any ci 
•taneee. The meul ring, Y. is truly tamed 
lathe, as well as the cavity, or crll, formed 
reception; tlien, to get it into its place, it is 
by a saw into five segments. Tlirce of the 
which it is divided, point to the centra, b 
other two are parallel to each other, and tb«i 
is put into its (ilace (after the leather and 
rings arc introduced), by putting in the four 
mcnta separately, Aid the one wlih parallel si 
put in last. The cylinder, D, is then put do«« tl 
its place, and ready for action. 

This plan of a divided ring was first used by Silr. 
Peter ICior, who, since the cipiration of Mr* 
Bramah's patent, has made several hydri 
presses. In the original construction, the r' 
bead, of the cylinder, which kept down the 
cup, was held down in its place by several 
bolts ; but as these bad to bear a greater forv 
tho whole power of the press, thry were fireqi 
torn out, or strained, so as to cause leakage, 
upper part of the cylinder above tbe ring, 
filled with tow, or other soft packing, imprreott/d 
with sweet oil, which Is confined by a thin ' ■ ' 
ring. This packing serves at once to - 
cylinder with oil, and to prevent the nJ;..: -.._.. 
any subatauce which might injure the sutfaeeof Iht 
piston. 

The pipe, B, is made of copper, and its jeiati 
are made as shown in Fig. 3. The end of tbe fi^ 
has a projecting piece soldered, or screwed, opna 
it, and this fits into a cavity formed in the metal oC 
the pump, or cylinder, and it ia forcibly p 
into its ^eat by a perforated screw, W» which 

into the cavity. The joints art raadcred tight' 



MAGAZINE OF SCIENCE. 



210 



^, or wasber, intcrpostd Uetween the vtxd 

e AnJ Lilt! bolluu of the cavity in (be 
or pump. 

Unutatic pmu if not liable to gf^t out of 
t if any excrtneuus macter nttucbes itaelf 
of the valvea, their action wiil neceuarOr 
}dtd tiU it be reipoTed ; for tbi* pur|Hiw 

ou be tnken out. Tbo valve ai T hat a 
\, G, fitted over it, ouJ thia reg^alitea the 

the valve; or. by unvcrewiiig the plug 

can be taken out. To get occeaa to tbe 
fCt the lower piece, N, of the pump must 

ed. The diacbarging valve, 1, may also 
ped by withdntwing ita screw, 
^ration of this pnrsf oiay be very readily 
Kded, by luppostnj; the pump, cylinder, 
■ctiog pipe, B, to be tilltd nitb natcr, and 
lequflte supply of vriiter is rontiined in the 
c When the bnndle of the lever, H. u 
i bringi up the pistua, H, ifhicb would 

UDta brncalh, if the otmoapbcix did not 
KaUr throu^'h the lower, or fiuctioa valve 

Fmp. The lever being then preaaed down, 
l-rod, by dtaceodiag. diminiahcf the ca- 
_ Kbs pump ; this causes the lower valve to 
forces the wiiter throuf^h the valve, T, 
paascfl, by the pipe, B, into the cavity of 
cylinJer, F, and raises tbe piaton, D, and 
tebicj Et together with ita load, a distance 
led to the quantity of fluid injected. On 
|aent riae of the piston of the pump, the 
E the upper valve prevents the return of 
and consequently tbe fall of the cylinder, 

rtition of the saoie pruceaa injects more 
the preasure may, in this manner, be 
■ great extent. \VheD it is proposed to 
i action of tbe press, tlie discharge valve, 
t opened by turning the screw back ; the 
k escapes oat of the press into tbe cistern, 
nacquently, the table. E, and tbe cylinder. 
id by their own weight, restoring the 
ita origiual sHuation, 

echaaical effect of the hydrostatic press 

of an ea£y cjilculation; for it is known, 

re be a mutual cotumunication between 

na of any fluid, whatever pressure or 

be eierted on the one, will be transmitted 

in a rntio proportional to tbe respective 

h column, consequently the proportion 

of tbe injecting pump to that of the 

coniLitutes tlie hydrostatic power of the 

1 tbe mechaoical effort exerted on the in- 

[mp is truusmitted to the cylinder, D, by 

Cntioo of the fluid, in a ratio proportiooal 

mjTarative areas. If the diameter of the 

( be one quarter of un inch, and that of 

h, tbuC is to say, four quarters of an inch, 

1 lodged upon the pinion rod, G, will be 

no with sixteen [>ounds lodged upon the 

(he weights of the parts of the engine 

rio, and moving with each piston, being 

0y included. And if tlie length of the 

3, be fifteen iocbca, and the distance be- 

k ccDtrca of motion, PO, of their action 

fistoo rod two inches, one pound at the 

will gfiin an advantage of 7^ times, when 

with tliut ^t N. Instead, therefore, of 

lands, upon tbe table, G, being equal in 

Boaoterpoise this last action, there will be 

upwards of 120 puuuds. But a man in 

VI of pumping, by a downward pressure, 

ut diliiculty, spply hit whole weight, and 



with great ease one-third, or one-fourth, of liia 
weight, fluppoae fifty pounda. In this rase the prra- 
anrc will be equivalent to fifty limes 1-0 pounds, or 
GOOO pounds, that is to suy, nearly three tons. 

To compare this engine with a acrcw in tlienry, 
it is necessary to inquire what flneoess of thread, 
and length of lever, would afford a purchase of I'iO 
to one. Suppose the thread of a screw, suhktituted 
la the place uf the cylinder, D, to bo ooe-teuOi of 
an inch thick, the distance from the top of one 
thread to the top of the next, will, in this ease, be 
one-Afth of an inch. This is the space through 
which tbe weight must rise in one revolution of the 
acrew ; the power must, therefore, move through 
120 times that space, namely, twenty>four inches. 
A lever, or radius, four inches long, will describe a 
circle somewhat larger than (his, and, consequently, 
such an engine would, in theory, be eiiual jn power 
to the hydrofitdtic engine wc have bceii dci^cribini;. 

But nhcn ilia subject is viewed pmctically, the 
difTcreoce between the two machines appears to lie 
very remarkable. All proctical men know how 
very large a port of the force, operating by mraus 
of engines, ia employed iu overcoming friction. 
Every one is aware of the entreme friction between 
solidn, nnil the very eli);ht frii:tiun which take* plocv 
between the parts of fluids. This is seen in the 
commou expedient of oiling the pivots of wheels, 
and in the very gradual drcuy of motion in fluid 
bodies, while solida moving upon each other stop 
at once as soon as the force ia difninished to « 
certain degree. The screw is an organ peculiarly 
Liable to friction, and this friction is always much 
greater than the whole of the redacting force, for 
there arc few iu5tancea where a screw will return 
from extreme pressure, when tlie agency upon the 
lever is vtithdrawn. It is also to be cooBidered, 
that the whole force of the weight, or resistancer 
acts directly upon the face of the thread of the 
screw, at the place where (he motion is required to 
take place. U has not been ascertained in what 
degree this resistance, or friction, increasea with the 
weight. In lighter actions, the simple ratio has 
been inferred, but under more severe pressures, the 
two metallic fai^cs eiclude the greater part of tlie 
half fluid matter between them, and apfvcar, by the 
magnitude of their resistance, to be attached to 
each other by a process of the nature of cohesive 
attraction. 



METEORIC IRON. 
I:« the room which occupies the north-eastern 
angle of the British Mu«ieum, one of those lately 
opened, is plaued that Urge mass of meteoric iron 
which was given to the Museum by Mr. Woodbine 
Pariah; it is part of the gigantic one which was 
found, and still remains in the pliin of Otumba. in 
the district of Uueoos Ayrca, in Sooth America; 
the weight of this portion of it only if l.luOlb. ; 
it is tbe fmesl specimen of the kind in Europe. 
Various theories have been advanced to account for 
the formatloD of these substances ; the hyiwthcsii 
which supposed that meteoric formations, ol which 
there are many specimens in thia apartment, had 
their origin in our own planet, is now found unte- 
nable, and has been abandoned. Tbe appearances 
of a thunder-storm and of a fire-ball have been 
ascertained to differ in various important respertSt 
and it is vain to allege th«it they are formed on Che 
grouud by the action of common lightning ; that 
thcy^ have been tbroiva up from tbe vulcanora la 



320 



MAGAZINE OF SCIENCE. 



equally difficult to ranrcivc ; the ulm which are 
fjected during the erupttunji of Vesuvius and Etna 
havf, by rraflon of their lightness, beeu driven to a 
considt^rnble height, bat there ii do power in nature 
tliat is known which poisesftea a iiufficienry of pro- 
jertjle force to propel solid mBsacs many hundred 
mttea throngh ao dense a mediam as the atmotpbere. 
It nppears, therefore, likely tbot these phenomeoa 
derire their formation from other rcglooB than onrt. 
The bypotheiia which has Buppo¥fd them to be 
generated in our Qtraosphcre is aot attended with 
less difficalty ; there ore scarce any two persons 
who hflve supposed the atmospherical formation of 
the roeteorolite, that have agreed as to the manner 
of their formation, Lapluce suggested the proba- 
bility that they might be thrown out from the vol. 
canoea of the moon ; nor (a It onlikely, as ToIca> 
Doea hive been dltcovered in that planet, and a 
projectile force equnl in power to that posscased by 
ours would be sufficient to propel fragments that 
might possibly reach the soifscc of the earth, the 
more especially, as no atmospherical resistance 
would be encountered, the moon being known to 
poRsesa none. It is demonstrated by calculation, 
that if n body ponderate be projected from the sur- 
face of the earth with safficieni force to give li a 
certnin velocity, it will never return; seven miles a 
minute is sufficient to accomplish this. From the 
moon the required Telocity to produce such an effect 
Is aboot four times as much as a cannon-ball, to 
that though the probability may be against it, the 
soppositioQ is far from Impouible. It is, however, 
more likely that they arc the ^agments of comets, 
bccanse those bodies, from their numbers, make the 
question of roern prob&bUity favourable to such 
hypothesis, as also, that from their nature they are 
subject to violent chemical ohangei, and from the 
comparative smallness of thrir dimensions a frag* 
ment thrown from tbem with any slight velocity 
would never return from the mass to which it ori- 
ginally bflonged, but would trnverse the celestial 
regions till it encountered some planetary or other 
body sufGciently ponderous to attract itself. A.U 
the masses of native iron which have been found in 
South America, and also in Siberia, have been as- 
certained by Howard, KJaproth, and Chlsdni, the 
RuMian, who wrote an account of the Siberian mass 
of iron, to contain nickel, and exactly resemble the 
iron foand in the stones which have fallen from the 
atmosphere ; there is not a doubt but they have the 
same origin, the more to, as it has been shown by 
the above celebrated men, that real native iron ia 
dietinRuished from that of meteoric origin by the 
absence of nickel. 



» CALICO PRTNTINO BY ELECTRICITY. 
S^CABCELT a week elApBca witliout witnessing some 
ettTBordinary discovery in electricity; the foIiowiDg 
is one which at present promises to be of consider- 
able Tslue, if the time required to perform the 
process be not longer than the purposes of manu- 
facture will allow, — an entirely new application of 
the science is now proposed. This Is nothing less 
than the psttern printing in mnumerable colors, 
of calicoes and other piece goods, by the sole agency 
of the galvanic fluid, for which letters patent have 
already been qjanted to the inventor. The process 
may be thus briefly described :— Both in the old and 
new plini, titr goods are previously immersed in a 
chemical solaiion, called a mordant (of wliich 
there ore thrtc scpaxalo kuids)| and which pre|i«res 



the cloth for the reception of the eolora. lliia 
done, the part to receive the Impresaion of tb* 
pattern, is extended over a flat surface of pLsttnsoit 
to which the negative pole of a battery is attsdiid* 
Upon the cloth thus arranged is placed the metaUio 
pattern, formed for instance of a piece of copper, t 
piece of silver and a piece of iron, the three ar* 
ranged in tbe shape of a flower, and faatened toge* 
tbcr by convenient means. A stream of voluic 
cicclririty is then conducted to this metmlltc pattmi, 
with which the positive pole of the battery has bees 
prcTtously attached, the cloth while tbe mordant ia 
wet, acting as a conductor. Metals form en osyda 
or some other compound, by the agency of ToliaJe 
electricity ; in consequence of which certain colon, 
dependant on th^ mordant, are impressed oo the 
cloth. In tbe instance wc have named, the cofTptf 
representing a leaf, would give out a ^reen ooloTi 
tbe stem of silrer a brown, and the iron a Mm. 
By this procets we are given to undersund* tliat 
the most minute patterns may be printed with t 
degree of accuracy otherwise unattainable, and thilC 
every description of piece goods may thus be printed 
with facility and success. 



PREP.\R\T10N OF THE GASES. 
Thk preparation of coal gas, of oxygen, bydrogflBi 
chlorine, and nitrons oxyde having been givsA 
in former parts of this Magaxine, the other gssn 
only will be treated of. 

Tu procure Xitrogen Com. — Waib a piece of M 
well, and cat it into very small bits ; pat thew iaM 
a tubulated retort and place them over a 
Now poor in some diluted nitric acid, and 
the beak under a receiver standing on the s! 
a pneumntic trough. Nitrogen gas will come ow. 
anil fill the glass or glasses. Nitrogen gu ia aom* 
what lighter than atmospheric air, of which it totan 
about three-fourths. It exists abundantly in natart, 
is the peculiar and almost cbaracteriatio ingrediwt 
of animal matter, tlie basis of the nitric acid, 
one of the constituents of ammonia ; it la 
of indefinite condeniatioo and expaasion, lika 
mosphcric air. 

todme Vapour. — Put a small quantity of 
into a retort, and hold it over a lamp : when 
considerably (about 300") a very beautiful 
or gas will come over, which may be reocl' 
jars on tbe pneumatic shelf, over vrater. 

Carbonic Acid Gat. — Into a glass tumblflr 
half an ounce of powdered chalk, and add to 
drachm of sulphuric acid. Very tittle agitAtion vtU 
take place owing to the want of power which tkl 
■cid haa to diffuse itself among the paitieki rf 
chalk. But if the tumbler be ooe-third filled «tt 
water, the acid will hastily combine with Ic ttri 
thus becoming diluted, will present ao large a MT* 
face to the chslk, as to attack it at all poinlft 
seining the lime, and driving ofT the carbonic and 
with great effervescence. By holding the nose oitf 
the tumbler, the peeuliar odour of thn carbdob ^ 
acid may be perceived. When the ftflerreteeow • \ \ 
at an end, a white powder will subside at thi ^ 
bottom of the tumbler, which is sulphate of Hi* ^ 

Ditto by Com^iafion,— Immerae a piece of 1^ >^ 
nited charcoal in a jar of oxvgcn gas. A tMf ^ 
beautiful and rapid comhustioii will immedlatslf j 
take place. The charcoal will at hut be consuMi ^ 
and of course the combnsiion wiJl cru*r. ''>" '«• ^ 
spection, the {jlasawill he found filled wii: 
aciU gas. Thisgii will be absorbed by (^ 




MAGAZINE OF SCIENCE. 



221 



witer («Wch it will render turbid) 
ifafl bottom of the jar ; from thii com- 
; may aftervrarda b« expelled by diluted 
idd. That carbonic icid bu been fonn<>d, 
»e proved bj the eitioction of a candle, 
me. 

Gu, — ^Thia goM may be procnred by 
If an ounce of meroury or copper filinga 
nlated retort, and pouriuf^ over them an 
iilnted nicrotu acid. In combining with 

a considerable quantity uf gu will be 
bich may be received in a jar uver water 

or Bydro-Chhric Gas. — Put an ounce 
I of aod* Into a tubulnted retort aborc a 
pour an ounce of diluted aulphiuic acid 
ic aoda leares the muriaCio acid (n^hich 
in a ^aaeooH form) and attaches itaeJf to 
irie acid, forming aulpbale of soda. The 

received in a Jar, over mercury. 
ing, or Protoxide of CA/onne.— Pour 
of muriatic acid, diluted Tvith an ounce 
water, orer ooe ounce of chlorate of 
retort placed over* lamp, the beat of 
athcr gentle. Receive the gua which 
er mercury. Thia gaa haa a yeUowiah 
Bce. 

^cwf Gas. — Four two ounces of aul- 
OTcr an ounce of copper filings In a 
and place the retort on a ring OTer a 
ebulUUon (that is, the action of the acid 
) commences, plunge the beak under a 
diog in a mercurial pneumatic trough, 
h it the auIpharouA acid, will aaceud, 
ing the mercury, will fill the glass. 

Got.— Thu gaa ia generally pro- 
animal matters, and by ita readioeis to 
carbonic acid, we are enabled to 
a tangible, or concrete form, as carbo- 
onia. The following methods of pra- 
niacal gas, synthetically, will be found 
satisfactory, insomuch as they thus 
position of tlus gaa, which by analysis 
been accounted a compound of nitrogen 
jea : put tome granulated tin iato a tea- 
DOT over it a little strong nitnc acid, so 
Xle more than to moisten it. Ttte metal 
Itod on by the acid, aod red fumes of 
I will arise : when this action haa ceased, 
the cup a little of the solution of pure 
L Tcry pungent vapour or g&a will now 
b from its odour may be known to be 
Here we mu&t be assured that the am- 
Jrnthetically produced by the decompost- 
I snbstincea employed ; for we are awara 
Ilia itself did not enter into the compo- 
bmonin being composed of nitrogen and 
we must account for ita formation by the 
i UwM gaaea in such proportion aa to 
k iht firat instance, however, the am- 
lot perceptible by its odour, because at 
of ita formation, it is attsckcd by some 
I acid, and thus nitrate of ammonia is 
th oxide, or nitrate of tin. The addi- 
tion of potass, however, by combining 
rio acid, liberates the ammonia from its 
te, and consequently its odour is exhaled. 
lleH Hydrogen Gas. — Put one ounce of 
iron into a tubulated retort, and ponr 
ounce of diluted sulphuric acid. The 
in atlAcking the iron, will receive 
Um oxygen of cbe water (by which 



it was diluted) in oxidising the « metal before it ia 
converted into sulphate of iron. The hydrogen of 
the water will thus be free to combine with tha 
sulphur. The sulphuretted hydrogen may be re- 
ceived in the common way in a pneumatic apparatus, 
or in a bladder attached to the beak of a retort. 
The following ia M. Gay Lusaac'a method of pre- 
paring sulphuretted hydrogen g&a : — " The way I 
obtain this gas is, to mix two pints of iron filings 
with one of flowera of sulphur, then to put it into 
a mattras with as much water as will give it the 
consistence of aoap, and heat the vestiel, tu promoto 
the union of the sulphur and iron, which soon 
shows itself by a great disengagement of heat, and 
a black color spreading through the whole mass. 
Then, sulpharic add diluted with four times ita 
Tolume of water, disengages the sulphuretted hy- 
drogen with nenrly as much rapidity as ^m an 
alkaline hydro-sutphnret. The mixture should 
never be prepared before the gas Is to be obtained." 

HydrO'tincic Gas. — Pour diluted anlphuric acid 
over some broken line in a retort; place tha beak 
under a pneumatic shelf, and receive the gaa which 
cornea otor, in jars. Hero the sulphuric acid, in 
its action upon tho zinc, receives the aid of the 
oxygen of the water, by which the metal is oxidised 
previous to ita solution. The hydrogen in conae. 
quencc is set free ; but before it leaTss the retort, 
it combines with a portion of the zmc in very 
minute particles ; by which means it ia converted 
into hydro-zincic gaa. 

Arstniattd ilydrogm Gas. — Put 4 drams of ilnc 
filings into a small retort with 2 drams of filings of 
arsenic; and pour over them I ounce of diluted 
sulphuric acid : if the beak be put under a bell- 
glasa on the pneumatic shelf, arseniated hydrogen 
gaa will ascend and displace the water. Here the 
acid, in acting upon the zinc, decompoaea the water 
used as a diluent; the oxygen of which oxidises 
the metal, whilst the hydrogen is set free to unite 
with the arsenic. This gas bums with « rerjr 
delicate bright flame. 

PhoaphtirpHfd Hydrogen Gas. — Put into a small 
retort half a dram of phosphorus in imall piecM, 
and a dram of zinc filings. Pour orer these, 3 
drams of sulphuric scid diluted with 6 drams of 
water. Put the beak of the retort under a belU 
glaaa in a pneumatic trough : phoephuretted hy- 
drogen gas ascending will displace the water, and 
fill the glass. Several gUsies may be filled from 
this quantity : one of these glasses should have a 
stop-cock, by which bladders may be filled, or by 
which it may be allowed to issue for combustion in 
atmospheric air. In thia experiment, the zinc and 
acid decompose the water, whose hydrogen being 
aet free, combines with the phoaphorus, and both 
are evolved in tho gaaeoua form. 7!1ie preparation 
of this gas may be varied by putting b grains of 
phosphorus, cut small, and 10 groins of zinc filings 
into a wine-glass, and by pouring over them half a 
dram of sulphuric acid diluted by a dram of water. 
Globules of phosphuretted hydrogen gaa will ascend 
to the surface, and will inflame aa soon as they 
come in contact with the air. This experiment 
may be varied by holding the beak of the retort in 
a perpendicular position, and allowing tbe gas to 
ssceud and combine with the atmo^pberic air. In 
doing thia, a continued stream of fire wilt be seen 
to issue from the liquid below. This is an inte- 
resting experiment. To prevent inconvenience, the 
retort may be placed in a basin, in an upright poai* 
UoDi^tnd the ingredieiiti nay thai be pvurvd in 



239 



MAGAZINE 01 



utitliout incooTenteoce. A itOl farther Tari*lidn in 
the mode of combiaaLioa betn^een pbofpbora» aod 
bjdro^D, Ib u fuUooi : — PrepAre % jir of hydrogen 

Su over mercurj, br Uie decompoiiCioD of water 
y Bttlpharic a».'id lud iron filing. Pus two or 
three aninll bits of pbonphorus op throngh tbe 
mercory, that thcj mar remain in conUct with tbe 
hydrogen gu. la the course of tea or twelve 
buun the rnmbinatinn will be complete. 

SiUcattd Fluoric Ga». — PulTcriM an ounce of 
floete of lime (flnor ■par), and half an ounce of 
glua ; pat these into an earthern or gliaa retort, 
and poor over them an oimce of sutplmric acid : 
receive the gas in glaat jara over mercury .•^water 
Abaorbi so much of this gas, tiut it can hardly be 
collected over it. This gas being already salnrated 
with ailez frooi tbe powdered gUxs, baa no sction 
on any gla.<n vesaela which may receive it, so that it 
may be kept in them for any length of time. 

Flua-boric Gmt. — Put into a tubnisted retort 4 
drams of puiveriaed fluale of Lime, 2 d/ami of dry 
boracio acid, and 3 ounces of sulphuric acid ; give 
them a tolerable l>cat ; the gas which cornea over 
will be the fluo-boric, which does not act upon 
glass, and may be condensed (as it is reaiarkably 
Absorbable by water) in the receiver, containing a 
few ounces of water at Che bottom, and surrounded 
by pounded ice, or a frt>ezing mixture : if tbe 
water has absorbed sufficient, the whole will be of 
an oily coaiisteoce like sulphuric acid. It may be 
prf>iirrved in a stoppered bottle. Irt tbe formation uf 
this lubsCaace, the sulphuric acid separatea tbe 
lime from ita combination, forming sulphate of 
Uine ; tbe two arids accordingly combine tngtther, 
•nd are driven off by the beat io a state of gas. 



GELATINOUS SUBST.VNCES AS FOOD. 
Trk commiaaioD nominated by the Academy of 
Science to examine the properties of gelatinous eub- 
stsncea as food have made their report. Tbeir ex- 
clusive attention to the: subject, and tbe nuineroos 
experiments tbey have made, warraut them in arriv- 
ing at tbe following conclusiuns : — 

First. — It ia impossible by anjr known proceas to 
extract from bones an alimeocary tubstauce, which 
eillier alone or mixed with any other substance can 
be a lubfititute for meit. 

Secondly. — GclHtine, albumen, fibrin, taken wpa- 
rately, nourish animols only for a short time, aod 
Tery insufficiently. These aubatancea, when un- 
mixed, soon excite insurmountable disgust, and to 
lueb A degree, that animals would mtber die tbaa 
touch them. 

t Thirdly.— These same principlea, united artifi. 
ctally, arc taken with leas repugnance, and for a 
greater length of time than when they are separate ; 
but tlifir power of nutrition is not greater; for the 
animals that eat them even in considenible quan- 
tities ultimately die with erery appearance of com- 
plete inanition. 

Fourthly. — The muscular flesh in which the gcla. 
tine, albaroen, and fibrin are organically combined 
with other substancrx, itnch as fat, salts, &c., even 
in very smalt quantities, is sufficient for complete 
and prolonged nutrition. 

Fifthly. — Bonea are efjually nutritious, but the 
quantity conaumed in four-and-twenty hours ought 
to be considerably more tbuu of meat. 

Sixthly. — All kind of preparation, such as de- 
WK-iion in water, the action of chlorohydric add, and 
particularly the cooTcrsiou into gelaliuom aub- 



stances, dioiiniabea the nutridrnts qoaUtlea U bones 
and even in some cases removes Ui«m allogMhcr. 

Seventhly.— Nevertbeleaa, the cooinuBUUMnluv* 
been reluctant lo pranOfiOKK, without hrther \a* 

vestigition, what may be the effr. • '' ' 
grlatinons substances mixed with 
whtu applied to the nourishmrtU w^ u..<. .^ ■ 
believe tliat direct experiments alone can tlifow toy 
degree of certainty on thia subject. They tax si 
present activtUy engaged in tbem. 

Eight! y.— Gluten of itoelf affords oODOplcta ni 
prolonged nutririon. 

Ninttily. — Pat aobstancea taken aalbeonlyftai 
support hfe for some time ; but t?i ' 

very imperfect and diturd^rcd oun 

cumulating In all the animal tiss^:^.. ;- ■■ 

a atate of oleine and of stcarioc, sometimn las 
state of almost pure ateorine. 



ON THE PROBABLE NVMBER OF SPBCl«f 
OF INSECTS IN THE CRE.\TlON.« 
nr /. o. wcsTwooD, Xfio. 
OuB great and pious naturalist, John Ray. (^b 
premier veritable natunilifte pour Ic rcgfif ALinmt," 
as the equally great Cuvier hai styled !: 
** Wisdom of Ood in the Works of the 
published »t the close of the aeventecatti 
tells us, nupectiog the number of firitisb la: 
"The butterflies and beetles are euch - 
tribes, that, I believe, iu our own oaf' 
alone, the species of each kind may Bm<> - 
or more. The fly kind, (if under that iianc ^ 
comprehend all tbe flying inaects, as wfII fsfft « 
have four, as such as bare but two v1t<. 
which kinds there are many subordinri: 
will be found in multitude of species to •- 
exceed, both tbe fore-mentioned kinds. 

leg insects that never come to be win>;' -. -- 

for number they may fall short of the Ilttrvf of 
winged, yet arc they also very numerous ; m by 
running over the several kinds, 1 could emilj <!** 
monstrate. Supposing, then, there be a theniaal 
several sorts of insects in this island ■^' 
near it, if the same proportion holds ^ 
Insects native of England and thoae of ini- 
ths world, as doth between plants domi 
exotic, (that Is, as I guess, nni- 'I'-'-i 
epecics of insects in the whole ran 
will amount to 10,000; and I do i- 
exceed than fall short of this sum." hubae^i 
however, In consequence of baring d^i 
grester number of Eogliih molhs sad b« 
he was induced to consider tbst tlic total 
of British insccta might be about 2,000 
of the whole earth 20,000. 

Linnicas, in the 1761 edition of the 
.Suecicse," described 1,700 species of 
bsbitanta of Sweden :-f and, in the 12th 
the "SysteraaNatune," llie whole number 
animals, (Swedish and exotic,) with which 
become acquainted, amounted to about 3, 

* tt must he buret In mind, lb<it th# foIIuwLog * 
do DOl apply to the number uf lutllviduala. but lo 
kind* or specie* at losrcti. Tbtwe wbo hare ol 
■warm of KiiKti at avnotldf," (whl''h. Im ^it«r«l 
myrlndx dT imlividuali uf tb« -• << 
percrti-e how Itiipmvllcajblc tl « 
ihf Tonntr queuUon. Tbe oim) 
which *xtsti In Uin (UlTerent ai^t in m nmo r» 
tnUrcitln^ vm-m* ol nature, ami i* • (jur«U»(i w«ll »< 
tb« 3if0Dti<iti «i tbe rnlomoioftuL 

t TUi* «u ill tus day ron»idPTv«l M) r , -- -■ ■ ■ ■; 
l'< Imluco Itvnumur lo nvion ihni S«re> - 
uumber i>r tti ttuccU thiui juiy ulboi Cvu 



MAGAZINE OF SCIENCE. 



233 



w look at the state of the acience of 
n the pre»ont day. Mr. Stcpbcna has 
Catalognu of named Rritiib insect*, 
lo 10,000; bdJ, since tbe time of iu 
nameroiu additions bare been made to 
; wu ft curious coiDcidence, tbat our 
ra« Thomaon, should bave hit upon thia 
, in order to give some idea of the viitt 
( stunmer iiueeU: and Mr. Stephens 
■dopt^d the Unea priated below ia italics 



By mjiitia. forth a( once. 
Uir- vtii: or all itte vnritdhiKs 
"3 parent cnn dJarlo**. 
Icn tUuiua/ui liiffervrU irOoi 



, whose general knowlrd^ of the 
lem eollections cannot be qoestioned, 
second part of hia " Hone Entomolo- 
ed in 1821, that there were certainly 
00,000 of tbe onnulnfte anioiaU (nearly 
with the Linnftan insects) preaervcd in 
collect ions. 

Cirby and JSpence, adopting a conjecture 
Ue, that the number of specifs of plants 
lewbare between 110,000 and 120,000, 
tt, ** as a vast number of phanerogamous 
ftangi are inhabited by neveral specie* 
h we may form some Idea how immeoBe 
t number of extiting insecta ; and how 
m Bay*a oonjeoture of 20,000 species, 
I dne wu reckoned a magnificent idea, 
DmporiiKiD I " After instituting a com- 
reen the numbers of British infiecta with 
Mah phanerogamous plants, whereby it 
t, on the average, thcrc are more than 
to each plant ; these author* arrive at 
ODt that, •' if we reckon the phaneroga- 
tblea of the globe, in round nnmbers, nt 
ieei«B, the number of insects would 
MW.OOO." If we say 400,000, we shaJl, 
t be Tcry wide of the truth. 
ipect to tbe rehttive proportion of the 
fen to each other, Messrs. Kirby and 
e* Chat the Coleoptcra may be considered 
at least one to two of our entire insect 
Now, howcTcr, that the same attention 
I apoa the minuter Hymenoptem. Dip- 
(epidoptera, as htu been lotig given to 
blcoptero, we find thi« ralralation gives 
share to the beetles. In 31r. Stephens's 
tbey barely reach one third of our native 
^ therefore, we Cake tbe group of pre- 
tties (being tbe one which baa been most 
ieatig;ated in the detail of its species with 
[ advantagea and assiduity by Dcjean), 
\ alCiwogb it did not bear, In the " Syste- 
U" a greater proportion to the«wbolc 
Ulca thia oxiB to sixteen, yet not only in 
Catalogue of the English spedrs. but 
general Catalogue of Drjean, the pro- 
Ich it bears to the whole Coleoptera is 
oixteen. And, at 1 have already stated 
Uaber of spcdes described hy Dfjenn 
mfed at 2.000, the whole number of 
Im above rate, would not exceed 10,000; 
tog -litKIO more for other known npeciea, 
r would not exceed 20,000 : and yet 
berbcim, in bis recent monograph upon 
Inidie, ttates that Dejean had iuformed 
X), that be then posteiacd nearly 18,000 
t and the baron bimpelf informp<) me, 
t^o^ that he poBsessed between 20,000 



and 21,000 Coleoptera. And by estimating the 
beetles, ai above, at ooo to three of the Insect 
tribes, we shoU only obtain 60,000. ^VhAC a wide 
field, therefore, remains to be invcftiguted, before 
we shall become acf|uaiDted with tbe 600,000 or 
even 400,000 species supposed by Messrs. Kirby 
and Spcnce to ciist ; and how absurd does it seem 
to considsr our eystemi, or rather system, aa firmly 
cBtAblished, whilat ao little ia comparatively koowD 1 



THE COCHINEAL INSECT. 
It ia now nearly fifty years since thia valoahlc 
commodity was conveyed into our Eoat Indian 
tcrritoriei, by an enterprising iadivtdoal, an officer 
in the Madras array. Thirty years ago the Spani- 
ards regarded thia insect as being inTolnublc to 
them, producing a revenue to Spain larger than tbat 
alTorded by their gold mioea, although tbey wero 
both derived from the oelf'Same source — the state 
of Mexico. It waa the desire of the Hon. Kast 
India Company to introduce the cochineal into 
their territories at the above period, and large 
rewards were held out to speculating adventurers 
to tempt and encourage them to colonite the inae^it 
on their various estates. But they could not luc- 
ceed in their new undertaking. It bos now, and 
particularly within the last two or three years, 
spread itaeir ovrr the face of the whole of the 
Indian peninsula that falls within forty-two dcgreci 
of north latitude, and has destroyed almost evrrj 
cactus shrub (the prickly pear) upon which plant '\t 
wholly subsists. It may be deemed somewhat re- 
markable, when the great volue of the cochineal 
insect is considered, that the natives have never 
encouraged it as a feature of commerce. Certain 
European adventurers have, howevtfr, within the 
last five years, endeavoured to turn the insert to a 
good account ; but they have oil of them signally 
failed in producing cureil asmples of any size, so aa 
to wear a favorable complcicion in the London 
market, when placed in juxta-poiition with the 
" grana fina '^ of Mexico and OaXaca, and as none 
of the parties bad had an opportunity of witnessing 
the luode in which tbe " nopaleries" in South 
Americd were managed, they were quite at a losa 
how to treat tbe in»cct. Some conjectured that tho 
fly was u wild species of the " coccus cucciuelircr ;" 
whilst others considered it was the wrong plant 
upon which it was reared in India ; and on tho 
other hand, it was decided that the climate was 
uncongenial lo the prosperity of the insect, which, 
although it proved highly prolific, yet never arrived 
at any size. The Indian cochineal yields a strnngrr 
dye than that of New Spain, and is in every way 
calculated to prove a truly valuable article of com- 
merce, if it could he brought to a siic equal tn that 
of the insect of New Spain. A gentleman living 
on the Coromandel coast, a short time since, fed a 
small colony of these insects upon the ** cactus 
inertnis,*' a species of the *• cactus opuntia,*' per- 
fectly free from thorns, snd which it is said tbe 
South American coccus cxcluaivtly feeds upon, but 
it quickly perished under the bite of the insect, 
although tho aniriialculte were not usually numerous ; 
and he was led to imagine that tbe large " acirnlnr" 
thorns which protrude from the lobes of the pricLly 
penr (for the leaves are truly lobate) would, if care- 
fully remored, tend conridcrably to promole the 
size of tlie insect in its growth. He also, among 
several other experiments he adopted in his treat- 
ment of the cochiaeal, rescinded a portion of the 



S'24 



MAGAZINE OF SCIENCE. 



exaberuit foliifc of the plant, tad dimiaiibed the 
quantity of the Unrie od the leavei, so u to afford 
tiie abrub a more fay)nble opportunity of 6tnig- 

f\\ag ugainst the innovations of the insect incubus. 
n this latter experiment he proved successful ; and 
he observed, as the vigour of the plant wai pro- 
tected, in a corrcq)Qnding ratio did the cocci in- 
oreoBc in size, nor were they enveloped so thickly 
in flooculent matter as those which were allowed Co 
thrive unattended to and neglected. Cochineal is 
•I this time selling at the public sales in Calcutta 
for eleven and tvrclve rupees per Her of two pounds 
avoirdupois, which is at the rate of 128. per pound ; 
and yet, strange to say it, the insect abounds 
throughout India, and with a little pains and at- 
tention beatowed upon ic, might be converted into 
a valuable article of commerce, and would, there 
can be but little doubt, in time expel the presence 
of the Spanish insect from the market. 



MEMORANDA. 

BrperimenU made by Afextra. CkarleM Green and 
Riuh, during three Rrperimentai Balloon Atcmie. 
—On speaking of various atmospheric currents, 
Mr. Green says, in reference to a constant current 
at a great elevation, *' It is my firm opinion, that 
to England, at a great elevation, the north-west 
current will, in general, be found to prevail throngb- 
ont the year, without reference to the direction of 
the wind near the earth.*' This current, according 
to Mr. Oreeo, varies in ita elevation, from 3,000 Co 
14,000 feet. Mr. Green describes this upper cur- 
rent as carrying his balloon at the rate of six miles 
per hour, when the lower current will carry him at 
the rate of thirty miles per hour. Mr. Green de- 
acribed, thut in one of bis atcents from Liverpool, 
he entered the constant current from the north- 
west, at an elevation of 14,000 feet, and in his dt' 
tetnt he entered the lower or south-east current, at 
an elevation of 12,000 feet. By the upper or con- 
atant north-west current, he describes himself as 
travelling at the rate of six miles per hour, and by 
the lower or south-east current, at the rate of 
eighty miles per hoar. Mr. Green stated the great 
nleaauri! he felt on witnessing the formaCion of snow, 
bail, and rain, at various elevations. On speaking 
of iht velocity of balloon travelling Mr. Green^ 
aayit, " The greatest speed I ever travelled with the 
balloon woa 97 miles in 5H minutes;" but he has 
often travelled at the rate of between GO and BO 
milea per hour, — Meteor. Soe. Lond, 

Railway Traffie.—Thc following are the receipts 
of the principal railways in operation for one of the 
weeks of last month, that is to say, up to the dates 
to which the respective retnms are made : Brighton, 
1,7S6/. ; BUckwall, 1,077/. ; HuU and Selby. 891/. ; 
York and North Midland, 1,765/.; North Mid. 
land, 4,G58/. ; Midland Counties, 2,923i. ; Birm- 
ingham and Gloucester, 2,245/. ; South Western, 
7,fi9W. ; Birmingham and Derby, 1,327/.; Great 
Western, 14,9;U/. ; Northern and Eaalcai, 859/. ; 
Birmingham, 18,596/.; Eastern Connlies, 942/,; 
■ad Great North of Enghind, 1,457/. 

Grnx» LauniM. — The best and cheapest way to treat 
grass lawns or banks that arc subject to crack 
In dry weather, is to fill up the cracks with any 
llglit sandy soil when they are most open in dry 
weather, and afterwards to roll the ground, when 




snffieieoCly aoft joat to allow the roller to mftke aq 
Impression upon it, bnt not when it is rtij aoft. 
for if so, it will cauae it to crack worae when it 
again becomes very dry. Peraercre in filling np 
the cracks ; if they are large aow a few gnMi aoeM 
upon the fresh soil, it will then toon beoome fim, 
and crack but little after the first year. — Omrdemm't 
Chronicle. 

Recovery from Drovming. — Little or no water b 
found in the stomach of a drowned person ; aad 
when it is preaent, it can in no way have contri- 
buted to death. The experiments of Or^la md 
Marc have proved that water ia never found iti 
bodies submersed after death ; and that it eaaoot 
be made to enter the stomach without the aaiiit- 
anee of a tube pa&sed Into the gullet. This fiet, 
and that of little or no water entering the langs* 
cannot be too widely propagated, as Che popolar 
prejudice is in fisvor of the opposite opinion : sad 
bodies taken out of the water are stall rolled oa 
barrels, and held up by the heels in order to dift> 
lodge it i a practice fraught with the greatest iaih 
ger, if the smalleat chance of rcsuscitatioo eiist* 
Xh-. A. Thornton. 

Preaervation qf Meat. — The new proccai fir 
preserving meat by iujectiug salt into it by nuaat 
of powerful pneumatic presaure, will shortly be pst 
into operation at Bueooi Ayna tad other parQ €f 
Soutli America, where it ia well known that nttlft 
are extensively slaughtered for the exportatioo af 
their hides, the carcaasea being completely valodei*. 
The meat thus prepared will form an original articl* 
of export to this awl other countries, and, ihoali 
the speculation succeed, our provision markets msy 
be supplied with a new description of animal food 
at a very cheap rate. So extensive are the herdi of 
cattle and sheep in the immense and productive 
regions of the Pampas, that a traveller in Sonlh 
America a few years since states, that the carcawa 
of sheep were used aa fuel in heating furnaces.— 
Timet. 

Biiuminotu Shale. — A new branch of Indaitry 
aeems likely to organize itself in Belgium. IV 
different produce extracted from bituminous shalat 
by means of the works established about ten months 
since ou the banks of the canal, near Lackea, 
merits the attention of contnmera, eapeciaUj the 
extracts of oil and charcoaL This last productioo, 
of which extensive application has been already 
made in the augar-refioeries, and particularly ia 
that of M. de Vuidenberghe de Binkum, at Tu-lo> 
roont, may scquire great importance at a mODcaft. 
when the depreciation of sugar cannot be balancai 
but by a diminution of pri<x upon the original Bia< 
terials of manufacture. A reduction of thirty prr 
cent, on the price of charcoal, fit for refining, woald 
offer BB important advantage, and it is to be hopt4« 
that the eiperiment may prevail over the prejudioa 
of those, who from habit, atop short on the road ot 
improvement The works of M. de Binkum sf* 
open to all manufacturera, who wish to avor* 
themselves, by personal inspection, of the advsa« 
tages that the employment of this kind of charcaal 
offers. The ahale charcoal posaeaaei» mortoreri * 
disinfecting power, which acta iaalantaoeouriy o4 
all the animal matters, even the moat fetid, 
transfonna them into a powerful manure, 
two applications of this preparation alone 
suffice to assign an important place to this 
branoh of iodnatry,— Xe FuuU, 



M^-PnutMlbv D. ruAHoiB, 6. ^^'hHeHonwLsDa, Mll*EibLPubl|i.h«d by W. BainAtx. 1 1 . pBt«nwat«r 

iwkkk arc ajuwvml M«nUil>-,; to trc adOirficd t« the fdilor, at zr. Co1la|« Grorr, HUe ~ 




THE 



MAGAZINE OF SCIENCE, 

^nO ^cftool of arts. 



133.] 



SATUROAT. OCTOBER 18, IS4I. 



[Ud. 




BAIN'S ELECTRO- MAGXETIC PRINTING TELEGRAPH, 
'ou in.— NO. xiix. 



^'20 



MAGAZINE OF SCIENCE. 




BAIN'S ELECTRO-MAGNETIC PRINTING 
TELEGRAPH. 

A!< exhibition of ■ most inf^eoious mncliine U going 
oil ilftilj at th(^ Royal Polyterhnic loBtitutlon, the 
construction of which has excited the wonder of 
(be public and the admiration of the scientific 
world. The JnEtniment is called the *' Klectro. 
Magnetic Printing Telegraph ; ** the inventor ii 
Mr. Alexander Bain, prenouilj known M the con* 
triver of the electrical cIockB ; aad the object con- 
templated by him is the fuultlr^s and in«tanUi.ncnu)i 
trandmissinn of telegraphic inrorroalion, in n printed 
farm, between a central and any number of ra- 
diating }>oints. This iuventinn ii so remarkable an 
upphcfltion of the powers of electro-magnetism to 
the ordinary purposes of life, that we deem it 
worthy the profound attention of erery civilised 
govemtneot, as well aa of railroad proprietaries and 
other similar associations; and ou this ground we 
invite general attention to the ddtails i«e are about 
to give of its pbenonnena and practicnl working. 

We have so onen described the pru|>ertiea of an 
electro -magnet that we almost feel inclined to apo- 
logise for here re-introducing an explanation of its 
peculiar power ; but as many new readers will pro- 
bably peruse this communication who do not un- 
derstand exactly what it is — and who, in ignorance 
of its nature, cannot possibly nmvc at any com- 
prehension of our succeeding remarks — we obserre 
(for their enlightenment), that on electro- magnet is 
only a magnet during the period a current of elec- 
tricity is passing through the wires attached to it; 
and that when such current ceases, it is deprired 
of all magnetic power whaterer. This peculiarity 
(never yet satisfactorily explained) enables an ope- 
rater to establish and to break a magnetic influence 
at pleasure, and tbits to create motion in wheels, 
pendulums, springs, ficc., by the agency of electri- 
city alone. 

Mr. Dain*s printing telegraph possesses the grand 
element of permanent success — simplicity. Any 
person seeing it for the first time — that is, any 
person who cm rend — may be taught in five minutes 
to work it AS well as thoAc who are familiarly ac- 
quainted with Us mechanism. One individual only 
ii required for its manipulation. This person in- 
dicates what tlie telegraph has to do ; the machine 
uts in accordance; and the intelligence to be con- 
veyed from one place to nnothcr, howrrer di&tant, 
li instantaneously communicated in print, without 
any one bcinir present of necessity at the point to 
which it is traii*niittcd, the instrument, in this 
respect, being tell-acling. 

A result so aatonithiag as this may well appear 
incredible. A visit to the Polytechnic Institution 
we have named, will, however, remove all doubt on 
the subject. " Spciii^ is believing" according to 
the proverb; Dnd there, they who list may fee the 
thing done. Recummcoding oil ftceptics tn this 
Batiafactory test, we proceed to parliailarly describe 
the modus operandi of this moat interesting and 
very curious muchtne. llie engraving wlU assist 
our exploDAlions. 

In Fig. 1, some mAchinery is represented in ■ 
frame, the whole flupported on a common xtool. 
By attentively examining its various parts it will be 
acen that there are three principal portions namely 
— • cylinder A, an ontliinrjr clock wheel B, and 
a roller C. These three things rotate in the same 
way; the perpenrlicular axis of each h parallel 
with lUoC of ita neif^hbourf uxd the moUon of all is 



Ller^ 

'HI 



tpiral 

3 



conscq«enily honiODtal. Bendes 
dii-iitoos, there are other arrangements, 
snbordinate, hot really important. It w 
that the large cylinder goes round u 
screw, the effect of which i:i gradually to 
during the rotation. From underneath t 
an arm projects, haTiog connexion wit! 
and pulley, so that, as the cylinder 
rises too, in consequence of the attoc! 
Upon this arm the roller istixed; and on 
motion on its part, simultaneous with 
cylinder, and corresponding exactly wi 
result of the arrange mrnt. The wheel 
two (B), is permanently fixed npon its 

The uers to which these separate parts 
must first be described. The cylinder. « 
removable at pleasure, carries the paper (n 
on which the letters are to be printed ; th 
bring, with equal facility, put upon or tokl 
it. The wheel, between it and the roller, 
upon its p<'ri[)hery, or edge, the let: 
alphabet reguloriy arranged, incladiog 
The roller is charged with ink. Due note 
taken that the letters on tJie edge of the wl 
made oontinuatly to press upon the inklnj 
whenever the former is in motion, by whiet 
every letter is kept charged with ink. and r 
stamp its impression upon the paper on thi 
der; and it must further be observed, that n 
letter can be printed at a time, in conseqc 
the roller-like shape uf the parts. The spiral 
on which the cylinder travels, secures 
elevation of the latter as it rotates, the 
which is to prevent the same surfiire of 
being twice presented to the printing IcttR 
like manner, the ink is never taken by the 
twice from the same place on the roller, I 
for the reason already assigned, the grmdll 
of the roller corresponds exactly with 
cylinder. In the nicety of these details 
evtdpnce of the acute observation of th* 
They may appear to be of minor impo 
estimadon of those who are duxzled wit 
miry merit of successfully applying voltaic 
as a motive power, but the practical prinl 
once recognise an admirable attentioa U 
results, without which, however brilliant 
been the original conception, it would 
sttrihulet of an harmooioDi aod thei 
whole. 

Before farther description is gtrenr 
borne in mind, that the paper to be pril 
placed round the cylinder, and that tfatf 
charged with ink. The lettered wbeel« 
between the two, first receives ink from I 
and is then ready to print upon the paper 
that is turned towards it. The mechonia 
by menus of which the wheel is first made 
until it presents to the surface of the 
letter actually requireil. and afterwords to ftl 
paper, in order tu produce an impresst< 
meeluinical action is governed, or rather 
the electrical current — remains yet to be 
for; but we will first describe the other 
invention, namely, a dial-pLate or disk (n 
an acquaintance with which will fiicilita 
heniion of what Is to follow. 

In Fig. 2, it will be obsened, that this 
(also placed upon a sluul) has a rcTol 
B, and that the letters of the olphabi 
full stop, ore described in a circle u 
baud goa round by clock-work 



MAGAZINE OF SCIENCE. 



227 



Aa ivory peg (a Don -conductor) irro^ta 
Tttgtr%i uf the kaod, when required, bj htintf 
fa A hole in the plate betwetra the firit and 
rtterv of the alphabet, the exnct situation of 
is uiili(!Bted in the dingram. A ihallow 
c for the point of the same pe^ is made on 
ate underneath everj' one of the letters. If 
raon working the machine wants to make the 
stop at any particular letter, all he has to do 
plMtze the poiut of the \nrg upon the corres- 
sperture in the plate underneath that letter, 
e hsnd is stopped ; but the only place in 
the pfg can be introduced as a temporary 
re is the one we have mentioned. The object 
Shis arrangement is to obtain regalahty. En 
, we beg particular attention to these facts, 
the movements of the wheel charged with 
trrs iu the printing part of the mncbine, 
entirely upon the rotation of the hand on 
rfial-plate. the explanation of which will be 
presently. 

dcmcath the stool which supports the dial- 
to, 4 galvanic battery G is placml. which Is, of 
the source of tlie electricity employed. To 
Are attached three wires D, which are 
aght into metaliic connexion with the hnnd 
Bte, and afXcrwards condui'ted £ and 
parts of the pririting machinery. Two 
communicate with two eluctro-mog- 
Ihe action uf which the required effects 
need ; and the other is the return wire, the 
action uf which is ntrcessary in order to com- 
i galvanic circuit. One of Ibc electro- 
controls the operations of the letter-wheel, 
other gives motion to the cyhuder. 
lar attention is requested to the small 
dots A on the dial-plito. This circle is 
of pegs of ivory inlaid upon the dial- 
Durxitier corresponding with the letters 
oater circle. From the revolving hand pro- 
amall metal pin, the point of which travels 
e circle alluded to as the band goes round, 
a non-i-ondurtor. While the pin is paning 
ivory pe^, the electrical fluid ceases to flow 
Ik dial-plate to the other port of the ma- 
, because the tnterpositioa of the non-con> 
breaks the current; but the moment the 
has pasted from the ivory to the metal plate, 
connexion is again restored, and the current 
the electro-magnets aa before. It is this 
making and breaking the current which is 
of mechanical motion by the agency of 
Dagneu acting upon springs and wheels. 
at sappose the letUr O is required to be 
by the telegraph. The peg which con6nes 
at the full stop on the dial-plate is re- 
nd the hand then goes round. Its Arst 
I is from A to B. In this passage, the 
ive jxist mentioned first eatabliihes a cur- 
electricity between the dial. plate anti the 
Cro-ojognets in the printing part of the 
and then breaks it immediattjly after- 
r pasaing on to the ivory. I^t m now tracf; 
o of this pulsation of tlie elt>ctrical current, 
along the conducting wires, it arms both 
dml magnets with the power of attraction 
fraction oS a second of time. During this 
one of them is brought into piny upon the 
r. iihich is compelled to rotate s gireo dis- 
n consequence. The other sets upon the 
heel, which (by a simple but most ingenious 
BTTftugcmcnt, contained ia an inclosed 



box, to be recognised in the diagrom as having 
thereon the inventor'^ n<ime} is made In rotate tha 
exact diatince between tlie letters A sud B upon its 
edgo, the latter letter, by Uie operotion, taking the 
previous position of the former. A siniilar move- 
meat occurs with every subsequent letter until O is 
reached ; that is to say, that as the hand of the 
dial-plate posses over the intervening letters, a cur- 
rent of electricity U established and bioken with 
each, the effect of which is to make the letter-wheel 
advance a IcUer each time this is done, so thai 
when the hsnd of the dial-plate is it O, the sonio 
letter is presented by the wheel to tho surface of 
the paper, in readiness to give an impression. In 
i word, by this arrangement the letters on the whfel 
in the printing part of the machinery invariably 
correspond with those on the dial-plate. At what- 
ever letter on the dial-plate the band (s arrratrd, 
the same letter is presented by the uheel to the 
surface of the paper, in readiness to bo printed. 
This lost operation is instantaneously effected. Tli* 
moment the letter is in its proper plsce, a oon- 
nexion is established (by pressing d(»wn a metal 
spring C on tbe framr.notk of the dial-ptste) 
between the battery and the magnet which work^ 
the wheel, which latter is forced nguinst the pnper 
on the cylinder, on which it leaves the impression 
of the letter. In this way letters are first formed 
into words, and words into sentences. 

The uses to which this portable machine may he 
applied are innumerable. As on infttnntantous 
conductor of intelligence from one place to another, 
however wide they may be apart, by night or by 
day, in fine or thick weather, and invariably with 
unerring exactitude, it must at no du<t«nt: day. 
become an agent in the hands of every civiltstd 
government. The railroads, when completed, will 
extend from London, as a centre, to every port of 
importance in the country. If three wires were 
laid along the length of each, the distant terniina- 
tion being connected with the printing part of the 
telegraph, and the other with the dial-plate of ths 
machine stntioimi iu an apartment uC the Admiralty, 
it would be the ensieat possible thing to interchange 
communicstions between all the ports und London 
at the !>ame moment of time, the passage of each 
communication, with its return reply, occupying 
but a few seconds, by the emidoyment of a tele- 
graphic code of signals. We tokc this to he a very 
near approach to the annibttntiouof time and Epscc. 
At all events, news is transmitted from om: jiliice 
to another hy the agency of the electro-mngncLit: 
printing telegraph with the speed of lightning. 

Mr. Bain, the sole iuveutor and origmiitnr ni 
this very remarkable machine — a machine sa simple 
as it is ingenious — has given the result of his genius 
to the world without any hope of corresponding 
remuneration, indeed, of any remuneration si all. 
from ordinary sources. He has secured nothing by 
patent ; and the ronsequence is that cvrry manu- 
facturer of philosophical instruments may moke, 
and every company may adopt his printing tele- 
graph, without the necessity of paying to the in- 
ventor any compensation whatever for so doing. 
Mr. Bain's elect ro-msgnetic printing telegraph ia 
DO pbdosnphical toy. It is a machine admirably 
adapted to tlie wants of our ovni and neighbouring 
governments ; and it may with considerable advan- 
tage be also applied to a riuiety of objects in 
private undertaking!.— Po/y/ecAnic JwmaL 



22S 



MAGA2INE OF SCIENCE. 



SUGGESTIONS ON MUSICAL STRINGS 
AND INSTRUMENTS. 

Sr LEWIS UOMPKKTZ. 
ffUiMittd/fiHn juge 208. atwl ronehuUd.) 

" The want of covered strings on the doable bass 
cauiei the instrumeut oot to go so low as it ought 
for ita uiCt ita loweit note being only one nule and 
a half lover than the loweat note on a Tiolincrllo, 
which is so much ttmnller; though in qaantit)^ of 
tone the former is, of course, much deeper and 
foUer in the loir notes than the latter, wliich have, 
therefore, been mistaken by most persons to be an 
ocUve lower than they really are. It is tme that 
it generally takes its passages an octave lower than 
the former, but that has nothing to do with the 
capacity of the instrument, which only exceeds the 
other ns before stated by a note and a half. 

" If, then, properly covered strings could be got, 
the long dcBidtrratora would be accompUiihed by 
adding a fourth string to the double baas ; and thus 
a greater scale and lower notes would be obtained. 
In the tenor the first string is the same note as the 
second string of the violin, hot the length of the 
former is greater, which tends to produce a atroogcr 
tone, but mslcfs the string more liable to break ; 
and the first tenor string ou{rht, it appears, (con- 
trary to custom) to be a little thicker than the secoud 
of the violin, but not with the view of preventing 
its brraking. In the harp^ the body of this instru- 
ment being very small for baas notes, it renders 
anch notes less assistflnre than is the esse with the 
violincelio, but in order to counteract this deficiency 
as much ss possible, harp strings are rrry nearly 
double the length of those of the violincelio : the 
lowest C on the barp being just twice as long as 
the lowest ('. sharp on the viotinr^lo ; and what 
aeerns surprising is, that though harp strings are 
Bubsequently drawn up with nearly twice the force* 
still they stand tolerably well, while it ia not very 
uncommon for the fourth string of the violincelio, 
with little more thno hnlf the strain on it, to break, 
though of cat-gut, while the other is of silk, which 
is generally considered not so strong; whether owing 
to its being less loaded or to other causes remains 
to be discovered. 

" The pitch to which strings can be drawn, might 
indeed be used as a test, to prove the tenacity of 
the materials proportionably to their weight and 
elasticity. If, for instance, we wished to know 
wlkich was the strongest roatrriol for its weight, 
vrire or cat-gut, supitoving their clioticity were 
equal, we should only hove to see which could be 
drawn up to the highest note, and that would be 
the strongest for its weight. 

*' But thrre seems reason to think that the most 
elastic mnterial must produce the highest tone, be- 
cause it has morr latitude of spring, when each is 
drawn up nearly to their utmost; and, therefore, Its 
vibratioua must, if 1 am correct, be made in leas 
tine ; and, according to this idea, 1 find that the 
treble iron or steel serines of ptano-fortea are con- 
stdrrnbly sbortrr than the first cst-guL strings of 
the vtnhn, which is about a third longer tbnn the 
Tnme note on the piano-forte, iron being leas clastic 
than cat-gut. 

" The thickness of a string also affects its tone, 
independently of its weight, as a thick string ot a 
light materisl touches more air than a thin one of 
n heavy suhiftance ; this may cause a preference of 
one mMteriiil to anothtTf and alto add to the effect 
of covering to strings. 



" There seems to be some mistake cntertaitied 
respecting the degree of depth and aculroral at 
which notes am be discerned. There are no doibt 
limits, but not those geneirally miagmrd, the prewnt 
being, it seems, more owing to the faaila of Ihs 
means, than to the incapacity of the car» to dtscia- 
guish tones. Persons usually think when thi^y Bnd 
the very low notes of piano-fortes, ^c. bad. thai the 
tone itself is too low to be good, but this is not the 
cosp, tlie reason is, that the string ia too dkOft, If 
even it be as long as the instrument itself; perhapiu 
also, the belly of the instrument is too small, sad 
the estrenie treble notes are bad because the cnsit* 
rial of the strings are too weak to bear being loqgir, 
and perhaps the belly is too large. 

" Heraphma produce very fine notes, as lo« 
as the lowest notes which are not good in pisao* 
fortes. 

" Bat the tone of a string on an instnimcol is 
not all owing to ita own vibrations agaiosi the olr) 
this, in fact, causing but the smollrst part of tlM 
tone, as may be proved by the treble cones of 4 
string stretched without its pressing on a body 
the chief of the tone being by the vibrations of 
body itself, which, acting by mcnns of a much 1 
surface than that of the mere string, doea tlic 
execution, notwitbatanding that its vibrations SR 
ranch smaller. A string iu vibrating on an inAr»> 
meot is no where at rest, not even st the nut laA 
the bridge ; and it is the motion of the part reitw 
on the bridge which produces the chief effect t ff 
this part did not move, the body wooM t>e of DO 
use, but ax the string vibrates, the bridge and ntt 
resist, ond the feet of the bridge restmg on the bcUf 
of the instruioent, which is of thin and jiel^ni 
wood, communicates some motion to it ; tb» bcia( 
in violins, he, communicated to the back by caeofll 
of the sound post, (which, for what reason 1 kite* 
not, is omitted in the harp, guitar, and piano-forii,) 
likewise hy the confined air in the body, so thsltfa 
two surfaces vibrate in conjunction with the strinft 
or even with chords, and strengthen the tone. 
** The reason why the body of an instrura 
creases the tone, does not teem to be becauiv^ 
hollow, so as to cjiuse a reverberation or e 
generally imagined, but merely because it 
a larger surface against the air. It is admit 
•ound is increased in a hollow confine 
means of reverberation ; yet this increase of 
affects the eara of persons who are y^UKm 
and wuuld not be perceived by a peraoa 
The motion of the body, howrrer, is very 
to that of the strings ; the first being 
strong, and the Utter quick and tight, a great 
sure would be required to stop the vibrations 
body, while a slight touch n'ould stop the 
The action of the body is similar to what wo 
suit if n fist board were fsstenrd perpendii 
a stick like (he instnitnent used by scavengeri/ 
this even put in water and moved up and down 
as to disturb the water. With respect to the gt)(4> 
ness of ati instrument, there secma to be a ceriat 
size of surface and thickness of wood best od^i*'' 
to it, while the cliief object seems to be to fA 
their potntfi, and besides this the guodnras setoutl 
depenil in the body, obeying and undoing itaetf tt 
every note, and not sounding its own note in opp^ 
Eiition to that of the string, every instrument haHV 
a note of ils own. independently of the strtn|t< 
which would be hrJird by giving the unstrung bodf 
a blow as with a drum, iirtd this moyeausc otic M^ 
on so instrument to be better tJiau another. 



MAGAZINE OF SCIENCE. 



229 



ft have thoapht they could inproTe 
alow instrument by baving^ additional 
i it, to respond to those played on, but if 
tU^e exist in this it must only be in tho 
i itrini^* not being interrupted by the bow 
Dsin, which miiBt a)wny<i produce « flight 
|unst the itring, ai the bow goet only one 
tg a note, and the string backwards and 
t half of the Tibrations thereby being op* 
i that it is rather carious that a note should 

all, but that it rtoei sound it certain, and 
lon&l strings cannot, it s^omfl, add strength 
le. bKaase, though they nyaipathize iu the 
fthe originnl stringG. they are, through the 
of the air, only pulled to uiid fro by them ; 
plain that if the air move tbc string, the 
■DOC move the air, we might as well eup- 
t two men iDt|;bt run, and each at the same 
ttll the other on ; the additional string, in 
i dog to the first, thongh not so great a 
f the second string could not vibrate, as 
f ia the neiglibourhood of a vibrating body 

top its motion." 



E 



Ms OR. THE BASE OF FLINT. 

• iilieeous earth, the oxide of the present 
is the rnoflc nhumlanc of all the matters 
npDse the crust of the globe. It eonsti- 
1, the varieties of sand-atone and quartz 
eaten into felspar, mica and a prodigious 
minerals, which form the bosts of other 



hofioK. — Silica may be decomposed by 
It with potflssium, which deprives it of 
but a better process for obtaining silicon, 
t the double HuoHde of silicon and potas- 
th 8 or 9-lOthB of its weight of potussinai. 
ble tluoride employed, it prepared by neu- 
fluoftilicic acid with potash. .V ditfercnt 
■oggested by Berzelius, which consists in 
Uuiam in a tube of hard glass with a 
wn upon it, which is iillcd with tbe 
fluoride of silicon, sapplied from the 
at liquid contained in a small retort 
with the glass tnbc. The potauinm 
this vapoar, and at the end, silicon ia 
fluoride of potassium, in the place of 
But tbe silicon from all these proceases 
■ in combination with a little potaasiam. 
Bed with 8 little fluoride of ailicon and 
B unreduced. Hence, on applying cold 
the mass, hydrogen gas is discngoged, and 
brraed, and tbe silicon srparates. The 
■u produced con. with the aid of hot water, 
the silicon, which then oxidates and be- 
l&Ca. so that cold water only roust be em- 
9 wash the silicon, which may be thrown 
T. After a time, the liquid which pasaei 
r«actioa, which arises from its dissolving 
fluoride of silicon and potSMlum, of 
y, which has escaped decomposi- 
ed with tbe silicon. The washing 
•o long as the water dissolves any- 

fw. — The silicon which is thus obtained 
pnre state, a dull brown powder, which 
fingers, and wheu heutcd in air or oxygen, 
burns, bttl is never more than partially 
into silica. It mny be ignited strongly 
cracible without loss, and then shrinks 
■oquircs a deep chocolate coIoTj and 



becomes so dense ai to rink in oU of vitriol. By 
this ignition the properties of silicon are altered to 
a degree which is very remarkable in a simple sub* 
stance. It was previously readily soluble in hydro- 
fluoric acid, with evolution of hydrogen, and In 
cnustic potnsh, bat it is now no longer acted upon 
by that or any other acid, nor by alkalies. The 
ignited silicon also refuses to bnm in air or oxygen, 
even when intensely heated by the blow-pipe flame. 
Charcoal, it will be remembered, is more dense and 
less combnstible after being atrongly heated ; but 
that snbstance is not altered by hett to the satne 
extent as silicon. Mixed and heated with dry car- 
bonate of potash, silicon in any condition is oxi- 
dated completely, ita action npoo the carbonic add 
of the salt being attended with ignition, and carbon 
liberated. Silicon bnniB when heated in sulphur 
vapour, and forms a aulphuret, which water dia- 
solves, but decomposes at the same time, sulphu- 
retted hydrogen and silica being produced, and the 
last, despite its usual insolubility, retained in solu- 
tion. Silicon likewise bums in chlorine ; and the 
chloride of silicon may be otherwise formed by 
transmitting chlorine over a miiture of charcoal 
and siticn ignited in a porcelain tube. Tbe silica la 
decomposed by neither charcoal nor chlorine singly, 
but acting together npon the silica, these bodiea 
produce carbonic oxide and chloride of silicon. 
This compound is a vobitile liquid. 

Siliea or SHieie Aeid. — This earth, which ia the 
only oxide of silicon, consticntca a number of 
minerals, nearly in a state of purity, such as rock- 
crystal, quartz, flint, sandstone, the amethytit, eaU 
oedony, cornelian, agate, opal, 8ic. The flrst 
chemical examinatioo of its properties and com- 
pounds is due to Bergman. 

FrefHxration . — Silica may be had very nearly, if 
not absolutely pure, by heating a colorless specimen 
of rock crystal to redneas and throwing it into 
water, after which treatment the mineral may easily 
be paWeriBcd. It is obtained in a state of more 
minute division, by transmitting the gaseous fluoride 
of ill! icon (floosilicic add) into water; or by the 
action of acids upon some of the alkaline com- 
pounds of silica. Equal parts of carbonate of 
]H»tash and carbonate of soda may be fused in a 
platinum crucible, at a temperature which is not 
high ; and pounded flint or any other siliceous 
minrral, thrown by little and little into the fused 
mass, dissolves in it with an effervescence due to 
the escape of carbonic acid giu. The addition of 
the mineral may be continued so long as it deter- 
mines this eDervescence. The mass being allowed 
to cool, is afterwards dissolved in water acidulated 
with hydrochloric add, which takes up tbe siliea u 
well as the alkalies ; the liquor ia filtered and then 
evaporated to dryness. Tho silica may contain ■ 
little peroiide of iron or alumina, to dissolve which 
the saline mass, when perfectly dry, is moistened 
with concentrated hydrochloric acid, and after two 
hnurs tbe acid mass is washed with hot water. Tbe 
silira remains undissolved; it maybe dried well 
and Ignited. 

Properties. — Silica so prepared is a white, taste- 
leas powder, which is rough to the touch, and fecla 
gritty between tbe teeth. It ii extremely mobile 
when heated, and is thrown out of a crucible, at a 
high temperature, by the slightest breath of wind. 
It is absolutely insoluble to water, acids and moat 
liquids. Its density is 2.66. The heat of the 
strongest wind-furnace ia not sufficient to fuse 
■ilicaj but it melts into a limpid colorless glass in 



230 



MAGAZINE OF SCIENCE. 



the flame of (he oxyhydro^n bltiw-pipf;. Silica is 
fonnd frequeatljr cr>'Bt«lliMd, ita orditutry form being 
■ liX'tidcd prism terminated bj a iix-sidcd pjrumid, 
tfl in rock-cryital. Sometimes the prtsm is very 
short or diaappears entirely, and tbe pyramid only 
is 8e«D, as in ordinary qnortx. 

Sohittle Silicic Acid. — The preceding description 
ftpplics to iiiica after it has been dried or faented, 
but silica ran also be obtained in a state in which 
it is soluble in dilute acids and even in water. The 
oxidation of the salpburet of silicon, in water, 
gives sUica in this condition ; tbe solntion when 
concentrated , becomes a gelatinous mnsa, like sixe. 
When tbe gaseous fluoride of silicon is absorbed by 
water, tiUca Kparates in large quantity in that 
gelatioODS condition^ and this jelly is soluble in 
water although it requires a large quantity to dis- 
solve it. Tbe Bolution of silica was foond by Ber- 
lelios to be insipid, and not to redden litmus ; by 
evaporation of the liquor the silica is deposited in 
the form of an earthy mass without a tracK of crys- 
tallisation, and capable of dissolving again io 
water. It is observed, however, that when sulphuric 
or hydrochloric acid is added to the solution donng 
evaporation, the silica obtained is nu lunger the 
Bf>tuble, but the former insoluble variety. The 
fixed alkalies and their carbonates, it is curious, 
effect a transmatation of the opposite kind, for 
when insoluble atUca is boiled with Ihem, it Is gra- 
dually converted into the soluble species and dis- 
solves. Berzelius finds that this change supervenes, 
without decomposition of the alkaline carbonate or 
any eacapa of carbonic acid. The alkali in this 
tolutioD may be saturated completely with an acid, 
without any silica prrcipitating, which proves that 
that body is dissolved in tbe water and not in the 
alkaline carbonate. 

The water of springs and wells always contains a 
little soluble silica, which can only be obtained by 
efafrarating the water to drjmess. In some mineral 
waters the proportion of silica is very considerable, 
and it is often associated with an alkaline carbonate, 
as in the hot alkaline spring of Reikum in Iceland, 
and in the boiling jets of the Geyser, which deposit 
about their crater an incrustation of lilica. There 
con be no doubt likewise that much of the crystal- 
line quartz in nature besides all the agates* calce- 
donies and siliceous petri/actiont have been formed 
from an aqncous solution. 

The soluble silica seems to eziii in the class of 
minerals called zeoiiteM, which also contain water, 
and many of which dissolve entirely in dilute hy- 
drochloric acid. But it way be obtained from any 
silicate by fusing it with an alkaline carbonate, and 
aiterwards dissolving in dilute acid. The solution. 
on concentration, gives a transparent jelly, which is 
highly tenacious, and cracks ou drying, forming a 
mass like gum. When completely dried in the air, 
the mass is no longer soluble in water or addi. It 
contains a small quantity of water, which, however, 
according to Berxelios is hygroscopic; silica afford- 
ing him no definite hydrates, like those of other 
acids. Bat Dr. Graham says, " 1 should atiU be 
disposed to look to the state of hydration, however 
feebly the water may be retained, for an explanation 
ol the differences between the soluble nnd insolable 
Tuietiea of silica. Hydroflaoric acid is tbe only 
acid wlucb dissolves silica in both conditions." 

Siliecin, — A.lthough silica has no acid reaction. 
it is certainly an acid, and is indeed capable of 
displacing the most powerful of the volatile adds 
at a high temperature. It is capable of uaitipg 



with metallic oxides, by way of fiuion. ia a 
variety of pruportiuos. Its compounds with 
of alkali, are caustic and soluble, but those with 
excess of silica are insoluble, and form the v 
otglast. With alumina it forms the teas fujuble 
pounds of porcelain and stoneware. A Urge 
bcr of mineril species are also earthy siltcsces. It 
seems probable that silicic, like phosphoric actrfi 
forms several classes of salts, of which those tap^ 
taiuing the largest number of atoms of base artW 
most soluble, and afford, when decomposed di 
soluble silica. At the same time some differntfi 
msy exist between tbe silicic acid itaclf, as it cum 
in these different classes of aalts. such as tbcia 1| 
between ignited and onignited silicon. 



THE COTTON PLANT. 
Trkre are many species of this plost, and tt^ 
number is so constantly increased by the 
of botanists, that the varieties appear soared} It 
have any limit. I^nnKUs enumerated oaly 
kinds i Lamarck, in the " Encyclopedic 
diquc," recognizes eight ; CavaniLles, in his 
Dissertation on the MonadcJpbia Cla.<is of 
adds two other species to this number ; and 
taints, Poiret, and Uoeusch have each dcscnbcd I 
new species. 

Dr. Rohr, who resided daring many years stttr 
island of St. Croix, where be cnltivated cotton «idl 
extreme care, and studied all the characteristia nf 
the plant, describes tliirty-four distinct specic»|— 
but to these, much to ihe regret of the botaok4 
Bludeot, he affixes only their popalar names, 
cannot therefore be ascertained in what leapccCt. 
agree with the different species which haTe 
elsewhere described in botanical phraseology. 

Mr. Bennet. a cotton cultivator in TohscOi 
was an accorate and indefatigable abtenrer 
plant, remarked more than a hundred « 
considered them as never ending. Of I 
already enumerated, it is most probable 
are only varieties occasioned by the different 
of culture, soil, or climate, on a plant wh: 
been under cultivation for so many ages ; ai 
scarcely possible to determine what plants* 
feriog, con be regarded as forming separate 
or as being only simple varieties : while, at t 
time, tbe information of the scientific ma 
dtstiDct from that of the practical planter, 
becomes a subject of uo small difficulty to 
the knowledge obtained from each into one 
whole. 

To the cotton planter, it is a matfaer of much b- 
terest to become acquainted with all these distiafliff 
varieties, as some are incompuiabty more vibsUl 
than others. In the quantity and quality of ll^ 
produce. Some yield their downy hairest t«iaeill 
the year, others only once. Some bear ooltoa of 4 
long and delicate fibre, and of a beautiful whitemft 
while others ore found to be short and coorw. sad 
of a b&d color. Por want of this knuwirdge, If 
little regard is in general paid to the selection of 
seed, and the improvement of the stock* thai 
careful cultivator in first forming a plan 
mortified at finding an endless variety aa 
plants, snd can only hope to improve his plaonM 
by his own personal espencn^o, ftt the cost of Mid 
labour and many failures. 

It would be tedious and nnproGtahla 10 W 
general reader to go intp any minute partirolansi 
all the v&rietieB of the cotton plant, and UiertioK 




MAGAZINE OF SCIENCE. 



231 



jtre cbKractera, aud the points of dif- 
Ibfwe inoAt in caltifatioD, viU only be 

fy pi mm keHaceumt or common herba- 
ta pUnt) is the ipeciu moit genermllj 
It is nnniul and rues scarcelj to the 
ifhte«n or twenty inches. It bears a 
to flower, with a purple centre, whinb 
pod about the aijte of a walnut. Thi« 
Iripei borvtt, and exhibits (o view the 
n, in which the weds are srcnrcly em< 
t is sown and relied like com. This 
native of E^nia, and it the same which 
A^a Minor, aome parts of the Unitfd 
imerica, ia Sicdlj, at Naples, and in 

tjfpium arboremm, or tree cotton, is of 

t ^owth. If left withont being praned, 

I to its full heiKht, it has sometimes at* 

ffceen or twenty feet. Hie learea grow 

bairy foot-stalki, and are divided iuto 

epear-ahaped lobes. This abrub is a 

Idin, and probably the same as that de> 

Manx) Polo, ni eiiitinf; at GuaaeraL— 

saya the Venetian traveller, •' is pro- 

fa large qnantities, from a trw that is 

Irda in hrii;bt, and beam during twenty 

the cotton taken from trees of that 

adapted for spinning, but only for 

Wfpium Ifidieum, or Indian cotton. Is 
iriea not very dissimilar tu the last ; it 
^eons stem, and its branches are more 
ilalty at their upper parts. The shape 
likewise aoraewhat differs from that be- 
cd, this being divided into three convex 
Mm riiM to the height of ten or twelve 
btfaiiwt in full bearing daring several 
^■ometimea called likewise Barbadense, 
ts cotton — Barbadoes having been the 
.Went* India islands into whirh it was 

I from the East. This and the preced- 
are both cultivated in the West Indies. 
typium mti/olium, or the vine-leaved 
i, differs from the Indian, just described, 

of its leaves, which resemble those of 
llnis. This is indigenoni to the East 

is coltivated at the Mauritius. 
typium himhimt or hairy cotton plant, 
IKcies ; it haa herbaceous stalks branch- 
r, riaing almost three feet high, and 
h a thick down ; the foot*stalk and mid- 
mi are likewise hairy, and the leaf is di- 
hree unequal lobes. This pUnt is bien- 

II perennial in the wanner provinces, but 
Bes it becomes an annual, which change 
ea found to take plac« in regnrd to 
Ita of cuUivatiun in those situations 
rioter frost can attack the root of the 
It, and cause it to lose its vegetating 
&• species is said to be indigenous to 
tiw. 

(ipedea it distinguished by the name of 
fttififmim. No reason is assigned why 
iDQid have bestowed on it so singular a 
solution of the question was thought to 
»d. on reading in Stedman's Surinam, 
proea on the coast of Gninoa have much 
for the wild cotton tree ; unfortunately, 
I inquiring ftrther, we find thai the tree 
fith religion by the Africani, is (he lofty 
no lunilitade to thia dimiootire 



Ipriag no limiUtc 



plant, but reaembling, though far sarpusing our 
largest oaks In elegance and magnitude. The exalted 
dimennons and outspreading branches of the African 
bombax have ensured the favor and reverence in 
which it 19 held among a simple people, who, having 
" no long drawn aisle or fretted vault" raised for the 
observances of religion, have coasecratcd a natural 
temple under the arufile shade of which their ffada- 
m/m, or priest, delivers his lectores to the assembled 
audience. The little shrub called 0. rtligioman^ 
only attaining to three or'four feet in height, cannot 
therefore, by the most ingenious conceit, be made to 
ahow any connexion with the custom of the nativea 
of Guinea, and we must consent to leave the origin 
of its present designation in obacurity. Lamarck 
calls this species trictupidatum. Its stem is up- 
right, of a slightly red color, and very hairy. The 
leaves are sometimes entire, bat more frequently 
divided into three or four nnt very deep lobes. The 
flowers grow in a smitar manner to the others, but 
differ in color, being first white, then changing to 
rose, and finally to red. It is not known of what 
country thia ia native. Lamurck believes that it is 
indigenous to the loweat latitudes of Aonerica. 
Cavanillea supposes that it comes from the Cspe of 
Good Hope. It is cultivated in the Mauritius. 
There are two varieties of this species, — in the one 
the cotton is extremely wliite, in the other it is of a 
yellowish brown, and is the material of which the 
stufl^ called nankin is made; it may therefore be 
presumed that tbli apeciea Is a native of China, 
whence nankin cloths are obloiued. The yellowiih 
brown color of Chinese nankins is therefore the na> 
tural color of the cotton, and is not imparted by 
dyeing. The name ia derived from the city of Nan- 
kin, to which place the manufacture of these cotton 
stuffs was peculiar. 

The color of the nankins was long thought to be 
artificial, and Van Droam, who travelled in China 
with a Dutch embassy at the end of the last century. 
informs us, that the European merchants sent to 
reqncst that the nankins for their markets might be 
dyed of a deeper color than those last received. 
The fact was, the Chinrite had made the last lighter 
than usoal, in consequence of m great and sudden 
demand, which obliged them to mix their common 
white cotton with the yellowish brown. 

The various species of cotton just described, hare 
been distinguished according to their respective bo- 
tanical characteristics. Dr. Rohr classes the spedea 
and varieties by the different appearances of the 
seed ; other cultivators arrange the various kinds 
according to the facility with which the cotton is 
ginned, or divested of its seed; some again con- 
sider the distinctive difference to reside in the shape 
of the seed-pod, the number of its divisions, or the 
manner and time in which the cotton is retained iu 
its place after the bursting of the pod ; while others 
believe the only circumitances worthy of attention 
In the rlHRsitication to be those which regard the 
staple or fibre. 

Very white cotton ia not considered the best; ■ 
slightly yellow tinge, when not the effect of acci- 
dental moisture or of an inclement seuon, is indi- 
cative of greater fineness. 

The number of seeds in one pod vary according to 
the different species ; the pods of some containing 
only tenor twelve seeds, others as many as ttiirty ; 
while in all there is a marked difference in color, 
shape, and size. 

CTobe continued. J 



333 



MAGAZINE OF SCIENCE. 



REVIEW. 

A Omeiae and Practical Trra/Uf on the Principal 
DittoMet t^ the AirPamoget, Lung*, and Piettra, 
By A. Cothericood, M.D. CM., fifc—Price 
7'. fid. — Duncan. 

Although we are not in the habit ol renewing 
nedieal books, ;ot ne have, for once, itoppctt iBide 
from our usual course, aud fur three reasons. Firstly, 
becauH the author is well known in London as one 
of the most eminent physicians for these diseases. 
Secondly, because we have cau&e to believe, that a 
very large proportion of onr readers ire of the 
feooUy I and tlurdly, because these diseases, besides 
being the roost frequent, are also the most fatal in 
onr changeable climote ; so that oU hare a vital in- 
terest in knowiug their origin and cure. The author 
tells us in the preface, that " he baa cndeaTonred to 
adapt the Unguoge to the compreheniion of the 
noo-medicai reader, and, as far as possible to ar- 
range tfaevarioaB subjects, so that they may be most 
easily understood^ compared and referred to.'* 

The work treats of ordinary coughs and colds of 
every kind; whooping cough, croup, inflammation of 
the lungs, dropiiy of theluogs, asthma, consumption, 
inflammation of the pleura, water on the chest, and 
numerous other disorders — their causes, signs, 
progress, and treatment. The style shows Chat 
the learned doctor has written from long experience, 
lod not with the too common desire of making up 
n book. The prescriptions giTtri throughout are 
tmly valuable. Ve strongly recommend the work 
to lUl our readers, medic&l or uon-medicol. 



MISCELLANEOUS EXPERIMENTS. 

PrqHU-e a strong solution of phosphorus in anl- 
phnnc ether, and dip a. \necc of wUte silk in the 
solution; then, when the ether has evaporated, and 
tlte phosphorus begins to fume, apply a solution of 
Tiitro>muriBte of gold, made by dissoWlng the cry- 
stals of that salt in distilled water ; the silk witl in 
an instant be covered with a iplendid coat of 
metaliie ffold. 

Procted as in the last experiment, and instead of 
the aalntion of gold, apply, with a comcrs-bair 
pencil, a solution of nitrate of silver. Here the 
silver will instantly be reatored to its metaliie Wit' 
iiancy, and frequently attended by tpcatgict of a 
beautiful the. 

If a bit of white silk be immented in an ethereal 
solution of gold, and drii-d, the application of 
phosphorizcd ether will only impart a tn-oum color 
10 the silk i but if, as soon as the phosphorus bc^ns 
to fume, it be placed on the palm of the hand, and 
breathed on for a considerable time, the brown will 
be succeeded by a yurple tinges and the metaUic 
tustrt of the gold will soon begin to appear. 

^'hrn antiniuny is well fused upon charcoal, and 
if, at the moment when Its surface Is not covered 
with any panicle of oxide, we throw it suddenly 
upon the ground, the globules, into whir.b it divides 
in its fall, bum with a very iirely flame, throwing 
out on all sides brilliant fparkt, different from those 
of any other metal. 

Mix 6vc or six grains of sulphuret of antimony 
with half its weight of chlorate of potass, and 
then, if a sudden stroke be given to the mixture, 
upoo a steel anvil, it fulminates with a loud report, 



emitttDf , according to Foorcroy* ^flaaw aa 
nnd rapid as Ughtning. 

Evaporate to dryness a solution of goU^ 
with uitro-moriatii: acid, and dissolve tbe 
in a sufficiency of pure water to prevent ^e 
lallisation of the metallic salt. Thoroughly OioiiM 
a little mngocsia with this aqueous soluliuo, tM 
plaee the mixture in the son's ray». A cb«n]|:e ol 
culor will soon be apparent. It will firsi uke i 
faint violet hue, and in a fi:w hoora tlie whole irtU 
have acquired a very deep purple. 

Moisten • htUe magnesia with some '•' ' 

tton as before, and then dry the mixi 
dark. If it be then aubmiCled to the action (»i il^ 
sun's rays, it will acquire only a faint notrt, em 
by teeeral bours exposure. 

If the mixture employed in the last 
be now thoroughly wetted with pure walaCj 
again placed witliin the rays of the son, iH 
will rapidly change, and wiU acquire a deep 
approaching to crtmion. 

Moisten a piece of white riband with the 
solution of gold, and dry it thoroughly in tbv 
then suspend it in a clean, dry, transparent 
and cork it close with a dry cork. E: 
riband, thus secured, to the strong light of a 
sun, for half an hour, and only a /«iiaf ap 
of change ftf cvior will be perceived. 

Take the riband out of the phial that 
ployed in the last experiment, and wei it W' 
distilled water. If it be now exposed to tke 
rays, it will instantly change color, and will 
be stained of an indelible pnrjjie. 

Dissolve dry nitrate of silver in pure water j wU 
a little oil of turpentine, shake the mixture. uA 
cork it close. Submit Uie phial with its conteBti 
to the heat of hoiliug water for an hour, vhea tk 
metal will be revived, and the inside of the phiiL 
where the oil reposed on the aqueous solutton, «ill 
he beautifully tilvered, the revived metal forming • 
metallic ring, extending quite round the phial. 

Immerse a slip of white silk in a sotation <i 
nitrO'moriate of gold in distilled water, and dry II 
in tbe air. Hilk thus prepared will not be altm 
by hydr(^en gaa : but if another piece of silk bl 
dipped in tbe soliiiiou, and exposed while wH U 
the some current of hydrogen gas, iustaut signs ii 
metallio reduction will appear; the color will iihso^ 
from yellow to green, and a brilliant film of ndatm 
gold will soon glitler on its mr/ace. 

If a piece of silk be immersed in a solutlonif 
nitrate of silver, and dried in a dark place, SB^ 
then submitted to hydrogen gas, the silver will sot 
be reduced : but if exposed while uet to a stim 
of the same gas, the surface vrill quickly be costal 
with reduced silver ; various colors, such as blM 
purple, red, orange, and yellow, wUl accotspssf 
the reduction, and the thread* of the nlJt will Ion 
Uke iiher vire. During ihete esperimeiUB M^ 
Kitk Mhould be constantly kepi wet irifA diMtUld 
water. 

Dissolve some crystals of chloride of tin to 44* 
tilled water, then dip a piece of white silk in tia 
solution, and dry it in the air. If this be bO< 
immersed in hydrogen gas, no change will be ob* 
served ; but if it be exposed while iref to the ssffic 
current of gas, the reduction will soon comaMMi 
attended with a great variety of beautlfal colon, ■> 
red, yellow, orange, green, and 6iatf, vaiioi^ 
intermixed. 



LoiUKn(...4^nDt*d bv D. Pkavcii, 6. Whiti* Hun* Vjkxw, Mil* End.— PublUhod by W. DfttTTAiw, II. PatrraDolv Kaic 
Edlabui^h. J. MsKBiia— Gloagow, O, Baica aod J. Buiiisi.— Liwriiotil, J, Pauir. 




THE 



AGAZINE OF SCIENCE, 



^nD ^c&ool of '^xt». 



:.] 



T" 



SATUBDAY, OCTOBER 33. 1841. 



[Ud. 



Fig. 2. 



Fig. \. 



i 



4^-1 





MAY'S RAPID FILTER. 




STURGEON'S ELECTRO- MAGNETIC ENGINE, &c. 



1234 



MAGAZINE OF SCIENCE. 



MAYS RAPID FILTER. 

It U highljr important to the health of fimiliea, tliat 
water iatended for their daily coniuoiptioD should 
be ine from all imparities. 

Good and clear water ii also a Taluable acquiai- 
tion to such manufacturers as paper m&kera, dyen, 
J)leflchers, and calico printers ; and in order (hat 
fkmiJies and manafacturers abould bxve a constant 
uid copioiu supply of pure water, filtration, on a 
Urge scale, is necetsary. 

The sTstems of filtration already used by the 
public, fumifth filtered water in such trifling qoan- 
iiliei as to be of service only to small faiuilies, in 
addition to which, great inconvenience is expe- 
rienced by the (iUeri being constantly out of repair. 
and from their having to be taken away to be put to 
rights; while manufacturers, like the paper maker, 
dyer, bleicher» culico printer, S.C., who require 
such Urge quantities of filtered water u 120,000 
gallons per day. are without any system of filtritton 
whereby they can obtain pure water in such large 
quantities. 

Again, the riiiegar distiller, oil merchant, and 
sugar refiner, ari.' without any rapid system of filtra- 
tion by which they can clarify tbcir liquids; but by 
the method now to be expUincd, oils, vinegar, and 
augarjuice, are clarified in the most perfect manner, 
and at • very rapid rate. 

Fig. 1, of the accompanying engniTinga, is aji 
external reprraentation of n patent rapid filter, 
called No. I, which is eight inches in diameter, and 
twenty inches high, and capable of filtering upwards 
of 1500 gallons uf water, or otjier similar liquid, 
per day of 24 hours. 

Fig. 2, is a section of the same; A, the faUe 
bottom or well into which the filtered liquid is re- 
ceived, covered with a perforated plate, shore which 
there ts a layer of horse-hair or serge ; 6 is the 
filtering medium, which consists of prepared cotton 
divested of every particle of dirt and Krease ; C is 
an iron or earthenware pUte pierced with fine holes, 
or covered with wire gauze. A galvanized iron rod 
D passes from beneath the hottuni uf the filter, 
through the filtering materials, and terniioates in a 
screw at its upper end. 

Id preporing this filter, the cotton being already 
thoroughly cleansed, is soaked in clean water, and 
then packed or kneaded into the filter, taking care 
to press it well against the sides of the containing 
Tessel ; the plate C is then placed upon the oottoti, 
and above it a circular iron frame. The ant E is 
then screwed upon the upright rod until the filter- 
ing medium is sufficiently compressed. 

In the construction of large fillers for the supply 
of paper makers, dyers, calico printers, &c., re- 
quiring as many as 10,000 gallons of water per 
hour, the arrangement is slightly varied. In this 
case the rod D is dispensed with ; the cotton is 
packed or kneaded on to the covering of Ute false 
bottom, the full size uf thr tank or reservoir, and 
pressed dawn by an iron framework coTcred witli 
wire gauze. A screw and lever are employed in the 
first instance to give the required pressure, when 
iron rods, fitted with set screws, are liid down metal 
grooves placed two on each side of the vessel, which 
retains the parts in their proper position when the 
■crew is removed. 

The patentee claims the following advantages for 
his system of filtration, viz. : 

1. Tliat water may be filtered to any extent. 

2. That wuies, oilfi, vinegar, sugar juice, cyder, 



and all liquids, may be filtered without iDJuring their 
quality, taste, or color. 

3. That the sixe of the filters are small, in 
parison with the large supply of filtered water, for 
example, a filter of eight inches in diameter, by 
twenty inches high, will filter water at the rsie of 
1500 gallons per dny. 

4. That filters can be easily cleaned, and npaa 
the prefoises where they may be situsted- 

5. That the water is not made bard by filtnUoB, 
the filtering medium being quite free from cheoleal 
preparation, which in worthy the attenttnQ of dyers, 
bleachers, calico printers, color makers. Ace, vita 
require pure water without being made hard ly 
filtration. 

The advantages that strike us as being most is- 
portant, are the rapidity of its action, and the fadljll 
of cleansing, which latter can at any time beeffeetid 
in a few minutes, either by washing the cotton, or 
by putting in a fresh supply. 

With respect to the rapidity of operattoB, off 
which we inspected at the depjjt in Chathnni Flstf, 
not above two feet in diameter, was ftUering st tke 
rate of 7000 gallons a day. 

AMiere reservoirs, tanks, or back-waters s 
the premises of large establishment*, filtered 
can be had to any extent, as it is only nrrr<«ipr ts 
place one or more of these filters tn commutm-JitiaD 
with the supply of water, and the filtered witer 
he drawn off as fast as it may be retjuired. 

FamiUes, hotel-keepers, and tavern-keepers, 
have the filters fitted to their house cislcri 
which means filtered water can be hnd to any 
tent, for culinary and laundry purposes, ai veil tt 
for the service of tlie bed chambers and bath rOdill- 
— MfcAames' Magazine. 

STURGEON'S ELECTRO-MAGNETIC 
ENGINE, i^c. 
A A A A rspuksents a stout square board, 
forms the base of the engine- In two op| 
comers of tlte base board, are fixed the two Uf 
pillars B B, which carry a cross piece C C. 
cross piece are fixed two other smaller pillsri I 
which also carry a cross piece. In the cenl 
the engine is a vertical shaft, which turns fr 
two metallic collars ; one of which x& in the 
of the base board, and the other in the 
the cross piece C C. 

About hair way up the shaft are two drcihr 
channels, one above the other, as seen in the figam 
Through the centre of these channels, and at rlfU 
angles to their planes, the shaft passes, and is ~ ' 
to them. Lower down, the shaft passes thi 
the centre of on opening in the cross pi<ix 
also supported by two short pillars. On tbii 
piece, and concentric with the shaft, arc fixed I 
quadrantol metallic plates, separated fross 
other by narrow radial openings. 

Near the top of the shaft, and at right angtl 
it, is fixed a compound bar magnet N S, each 
of which is about eighteen inches long, ofie^ 
broad, and half an inch thick. Near tu the 
of the shaft is fixed anotJier simiUr com] 
magnet N S, with its poles in the opposite dirertiO ' 
to the farmer. 

In s circle concentric with the shaft, snd iti 
equal distance from each other, are fixt-d in the I 
board, the lower extremities of four 
of soft iron I 1 1 I, each of which \> *i< 

coils of copper wire. The coUi arouijc '^ 



MAGAZINE OF SCIENCE. 



331 



mted from enoh other by interrenin; eisct 
EmcIi Kct of eitremiltra of these copper 
loldciYit to one itoiit ropper wire ; hence 
initlea of the twentjr-four coils termioato 
of Ihirse Intler m'irei, four of nhich proceed 
t lower extremities of the coild, and are 
to the foar qaadrantal mctollic plates, one 

The other four atont wirea proceed from 
r parts of the coils and terminate by proper 
ma in the circular channeU, whiiih arc 
with mercury. Through the sidea of 
pufl four metallic stems, two through 

r inner extremities being in contact with 
turj in their reapcrtire rhanneta. The 

each pair are placed at 90° from each 
id the whole at right angles to the abaft. 
t angle which the upper pair forma, is on 
lite side of the abaft to that formed by the 
r. Prom each stem hangs a metnllfc wire, 
obliquely to iu reypectire quadranul plate 
(ro«» pin-r D D, which maintains a cnn- 
Itween lhe*e plates and the mercury in the 
banneb ; tran»fcrring the electric current 
plate to another, and consequently from 
» another, in their progress of revolution. 
i( the figure being disioitcd, none of these 
|g wires are drawn. 

p'ne is put into motion by the tppHcatlon 
I^HndricAl voltaic batteries of a single pair 
metals being placed in two porcelain jars, 
liicfa holds about three piuta. These bat- 
I connected with the condnrtors of the 
Ihrir terminul cups. One battery at each 
B lowest croas piece D D. 
HineJiions being properly made, the iron 
become magnetic in ^ucceision, and by 
Kttmctive and repulsive forces of the per- 
vigtiets N S, N S, and the temporary niag- 
'1, the former, with the shaft and ap- 
r are pnlled and driven round, the action 
ried on in the following manner : — 

that the pole N of the permanent magnet 
tfirrctly between the poles S and N of the 

magneta ; it will by this mean* be at- 
the former, and at the same time repelled 
ler. Hence it will be urged by both these 
urds the pole S. If now the contrivance 

at the voltaic connexions be broken just 

pole N arrives at S, the extremity S of 
bar wilt become neutral ; but the mo- 
Df the machine will carry the pole N to 
ia neutral jxiint. Now conceive that the 
rirea have been carried from their lost 

plates to the next in succeuion. The 
f this means have been reversed in all the 
m correspond in i; inversion of polarity has 
e io the vertical iron bar« ; hence, when 
f baa just pasMd the first bar, and whiUt 
by its acquired momentum, it will 
on by two other forces, in a similar 
the two first. For the extremity 
ed its polarity, it will now repel the 

drive it onward, whilst at the same time 
attracted by the next bar in succession. 
Meqnrnce of similar changes of polarity 
in all the four bars, the pole N is kept 

fetolving. 
has been said respecting the pole N, sp- 

y to the oppoisite polo S of the same 

that bj this means, the magnet and 

are continually urgo^on by four 

ftUractions and two repulsious ; and by 



considering that the lower magnet NS is. by tha 
contrivance, also ur^eU on at the same time, and in 
a ftimilar manner, by four other like forces ; it will 
eafrily be undenitood that the two magnets, with the 
shaft to which tbry arc atticbed, are kept in luotiutt 
by eight farces ; four of which are attmctive und 
four repulsive. Such is the contrivaoce for keeplttg 
the machine in motion. 

To the upper end of the shaft is attached a verti- 
cal spindle, crarrying an endless screw near its upper 
extremity, and revolving a^ the shaft revolves, iu a 
collar in the upper cross piece. Near to the lower 
end of this spindle ia a fly with three armx, equi- 
distant frnm each other, and each terminatmg with 
a heavy brass crescent. It waa originally the fly of 
a roasting jsick. The endless screw worka in the 
teeth uf a bniaa wheel, also a pnrt of the old jack. 
The arbor of tbta wheel runs in a frame attached at 
right angles, to the upper cross piece. 

CHLORATE OP POTASH. 
This Interesting aaliue compound has become tha 
object of n pretty extensive manufacturr, in conse- 
quence of its application to make matches for pro- 
curing instantaneous light, and a detonating powder 
for fire-arms. It may be prepared both in tha 
humid and dry way. 

Havj ng made a atrong solution of purified potash, 
or carbonate of potash, with from two to three parta 
of water, we pass through it in a Woulfe's apparatus 
a current of chlorine gas, till it'ceases to absorb any 
more. Chloride of potash and chloride of potaa- 
slum alone are formed a« long as there is an exress 
of alkiili in the solution ; but afterwards in the 
further reaction of the materials, the chloride passea 
into the state of a chlorate, and, as sncli, preiipi- 
(ates from the solution. During the tirsc half uf 
the operation, that is, tilt the potash be about one 
hnlf saturated with chlorine, as indicated by litmtu 
paper ceaiiing to be darkened and beginning to be 
blanched, only the chloride of potassium or murUta 
of potash falls. The process should be interrupted 
ot this point in order to remove the aalt, to wash it, 
to add the washings to the IJqaor, and then to 
transmit the gas freely through the solution. Aa 
the operation advances, less muriate of potash ia 
formed, and at length nothing but the pare chlorate 
is separated in cryjttaU. When linally the bubbles 
of gas pass through without being sensibly absorbed, 
the process is known to be completed ; the liquid 
may then be ollowed to settle, and be poured off* 
from the crystals of chlorate of potash, which are 
purified froni the muriate by diasolving them in 
three times their weight of hoillng water, and filter- 
ing the solution while hot. On its cooUng. tha 
nhlorate will separate in pearly. looking crystalline 
plates. It may be rendered quite pure by a second 
erystalliaatioii, in which state it does not uffecC so- 
lution of nitrate of silver. 

The above potash lye usually gets a reddish tint 
in the conme of the process, in consequence of a 
little mangancsieacid coming over with the chlorine, 
hut it gradually loses this color aa the saturation 
bfcomea complete, when the solution turns yellow. 
The tubes for conveying the gaa sboald be of large 
diameter, if they be plunged into the saline suln- 
tion, because the crystallization which takes plice 
in it ia apt to choke ihrm up. This inconvenirnre 
may, however, be obviated by attaching to the end 
of the gla» tube, a tube of caoutchouc terminatrd 
ki a small glasa fuunel, or simply the neck of a 



I 



S36 



MAGAZINE OF SCIENCE. 



cnoQtchoDc bottle with part of its body, whose 
width will not be readily closed with a saline cnist. 
The residuary liziviam may be used agatDst Huothcr 
opemtion, or it may be evaporated down to half its 
bulk, and set aside to crystallize, whereby some 
more chlorate will be obtained, mixed indeed with 
muriate and carbonate, from which, however, it 
maybe separated by a second crystalliiation. In 
general the pure chlorate obtaioed does not exceed 
onc-tcnih the weight of the potash employed ; be- 
cauau ID thus treating potash with chlorine, Atc- 
•Uths of it are converted into murialtf of potash and 
only one-sixth into chlorate, and a part of the latter 
■dhcres to the mariate, or U lost iu the mother 
waters of the crystallizatioD. 

The chlorate of potash maybe more conveniently 
manuroL-tured, like that of lime, in the dry way. 
St. llomer patented at Vienna the follnwinR method 
for that purpose in 1H21 : — Ten pounds of cryslul- 
Uxed peroxide of maDgsncse are tu be finrly pul- 
verizcd, mixed with ten pounds of plumbago, and 
tiiirly pounds of common salt, and put into a leaden 
retort. From the middle of the helmet-shaped lid of 
this vesiel, a lead lube, two feet long and two inches 
wide, c()ndunts to the receirer, which is a eqnare 
fturtheo pan, hard glazed both wiFhin and without, 
of the same capacity with the retort. The end of 
the tube mutt be made fast to a frame at the height 
of six inches above the bottom of the receiver. 
Upon it& inner sides four inches npart, brockets are 
to be fixed for supporting a series of laths or shelves 
of white wood, on which a number of little paper 
or paste-boord boxes are to be laid. In these boxes 
ten pounds of the purest carbonate of potash, pre- 
paired from tartar, are to be spresd. The receiver 
must now be covered with n lid made tight by a 
water hite. Twenty pounds of concentrated snl- 
phuric acid previouidy diluted with sixteen pounds 
of water, and then coolrd, arc to be pourrd upon 
the mixed mBtcrinIs in the retort, the lid immedi- 
ately secured, with the tube adjusted in the receiver. 
The whole roust be allowed to operate spontane- 
ously without heat for twelfe honrs. At the end of 
thi£ time the retort is to be lurroundcd with a water 
bath and steadily heated during twelve hours, and 
then left to cool for six hours. The apparatus tnuaC 
now be opened, the cakes of rhlorato of potash re- 
moved, and freed frum mariate by solution and 
crystnllization. 

M . Liebig proposefl the following process for ob- 
taining chlorate of jiotsth : — 

Heat chloride of lime in water till it ceases to 
destroy vegetable colors. In this case a mixture of 
chloride of calcium and chlorate of potash is ob. 
tftined. This is to be dissolved in hot water, and 
to the solution concentrated by evaporation, chlo- 
ride of potassium is to he addrd, and then suffered 
to cool. After cooling, a (pisnttty of crystals of 
cMomtc of potash is obtained, which are to be re- 
dissolved and crystallized again to purify ihcm. 
M. Liebig considers that this will be a cheap pro- 
cess for obtaining chlorate of potash. From 12 
ounces of chloride of lime, of so bad a quality that 
it left 55 per rfiit. of insoluble matter, he obtained 
an ounce of chhirute of potoj-h. 

The only ditticulty to overcome in this proress ia, 
from the chloride of lime not being so easily de- 
composed by heat as is generally supposed ; a eolu- 
tioD of it may be kept boihng fur an hour without 
losing its bleaching power. The best method \a to 
form a thin paste with chloride of lime and water, 
and then to evaporate to dryness. If tt be rctinircd 



to prepare it by passing chlorine intg cfMin of Um$i 
it is advanta|;eous to keep it very hot. 

The chlorate of pota«h which separates tnm fte 
solution by crybtallizstiuu, baa not the form et 
scales which it uaunlly poesesca, but ts prioaacie : 
whether thia is occasioned by some admixtore btt 
not been ascertained ; but on re-cryataUiziiig, it hs 
obtained in the usual form. 

The solution ought nut merely to be left to cool, 
in order to procure crystalt, for the cryatalliistiini 
is far from being terminated even after complrta 
cooling ; crystals continue to be deposited for thm 
or four days. 

The following modificatiun of the process br 
making chlorate of potash ia that of M. Vce. A 
solution of chloride of lime marking IS^ or 2ff 
\ianta6, is to be set opun the fire in a lead orosl 
iron pot, and when it begins to get hot, there 
be dissolved in it a quantity of chloride o( 
slum, suffident to raise the hydrometer 3 
It must be then concentrated an quickly as poati 
till it marks 30° or 31^ Uking care that it docs 
boil over by the sadden extrication of oxygen, 
concentrated liquor is set aside to crystalUzc 
cool plHL-« ; where a dejwsit of chlorate of 
formx. mixed with chloride of potassium. 
mother waters being evaporated to the dcnotyoJ 
36'', afford another crop of crystali, after wWA 
tbcy may be thrown away. 

The salts obLaiued at the first cryftallliation M 
to be re-diftsolved, and the solution being broo|U 
to 15° or 16^ is to be filteretl, when it will ofToM 
upon cooling pure chlorate of potash. 

Chlorate or oxymuriatc of potnih has a oooUnf. 
somewhat vnpleauant and nitrous taste. It does not 
bleach. At HO^ l\ 100 parts of water diunln 
parts of it, and at its boiling point or 320^ 
parts. When heated to dull ignition in a 
retort it gives out 39' 15 per cent, of its 
oxygen, ond bct-omes thereby chloride of pot 
When strongly triturated in a mortnr it i 
throws out sparks, ami becomes luminous, 
flogrates upon red-hot cinders like nitre: wkM 
triturated along wtlh sulphur, or phosphorus, K 
detonates with great violence, not without dan|(r 
to the hands cf tlie operator, if they be not ptt- 
tecled hy a thick glove. Similar detonations 
be produced with cinnabar or vermiUion, solpl 
of pcitassium, Migar, volatile oils, Slc. ; but 
can be effected only by the smart blow of a 
hninuitr and anvil. A mixture of »ugir or 
with chlorate of potaflh is readily inflamed 
drop of sulphuric acid, and thia experime-nt 
basis of the preparation of the oxygenated mi 
%a tbcy have been commonly called. The fuL 
formula forms a good paste for tipping 
matches, made of narrow slips of i*ithrr wc 
card. Thirty pans of the chlorate in fine 
are to be mixed gently with a spatula Uf 
with ten partj of flowers of sulphur well 
eight of sugar, live of gum arnbic, and cm 
vermUlion to give the whole a rose tint, 
by mixing tenderly together the sugar, the 
and the salt previously pulveriM-d : we then 
mudi water as shall reduce the mixture to 
paste, and Ustly introduce the sulphur ; after 
all must be nelt incorporated. The points 
matches, either previously tipped with snlpt 
not, are to bo dipped in that fut^te, so as 
eoated with a little nf it, and are lastly laid 
warm place till they become thorniighly dry. 
kindle oca of them, it must be touched with strosf 



MAGA21NE OF SCIENCE. 



2S7 



luric ■etd, ivbich for this pnrpose ii oilwllj 
-xtviW ireU.-«to|ipcTeJ phinl, anil tltirkeDtxl 
trhas. Aspen u reckoned the beat wood 



Of Uie jears a detoDBling priming for fire-amis 

brvn niarb aivd with tht* pcrcunsion locks. 

fintplest formula for makinj; it it to Ukc ten 

of eunpowder. to liiivUte it with water, and 

Kt\\ tKe resirJuiidi, while moist, with five parts 

« f^njirler of chlorAte of potash, reduced to an 

t^inclf tine powder. The paste foej be made 

ft^Oj thin, fur the salt is sparingly soluble in the 

...i' vs.r#7. and it mixes best when tolerably fluid. 

irr when dry is dangeroui to handle, Ueuig 

^ f-Tplode. But this danger ia guarded 

^< fail ft drop of the paste into each 

i:i cap, lud leaving it to dry there. 

ntuon of thia powder, besides muriate 

there ore gencrnteil a little sulphate of 

! chlorine gan, which rust the metal very 

«Li«h reason fulininate of mercury is 

Tred by many sportsmen as a detoaatiog 



lapoi 



reohams 



EW PROCESS FOR HARDENING 
EA.UTnEN\VAUE AND GLASS. 

tKT has jost hern made which is hkclyto 

irtaoC modifications in the maatLfacture 

iwane and glass. It consists in bringing, 

ei|Msare to heat, glass vessels of every 

loo to a state of perfect solidity sod opaque- 

wbich they entirety lose their transparency, 

jotre a color of whitih the shade "varies ac- 

to the proportions of the matters of which 

cofflposrd. The glass ono^ deprived of ilit 

salt! hy tliis process, which produces vola- 

aoquires, it is suid, remiirknble properties, 

infst others that of being proof against 

t, and of passing from the ki^lieft to the 

rm(ierjture, and ptre versd, wittiout danger. 

appear, from what we have stated, thai it 

tails, fusible and soWt-nt iu their nature, 

iCer into the composition of glass and crya* 

;en«ral, that their traniiparency is to be at- 

i and that once their evaporation is effected, 

only a silicioas matter, more or leas 

fnJJDg Co the elements that have concurred 

iDrmmtian. As soon, therefore, aa the soda 

beoomes volatilised, it naturally follows 

iflftM will lose its transparency, and become 

The art of ghua manufacturo will, in our 

toooer or Uter, derive instruction and 

Utna the almost insigmlicant phenomenon 

pcvma to have revealed to it, and articles 

feqaircd to sustain the action of a high 

iturr, such as crucibles, fire bricks, and 

m»f also be obtained from it, A patent 

taken out for the discovery. — Courrier de 



SUN AS A SOURCE OF HEAT. 

w which we inhabit, in its physical cha. 

ia in all respects analogous to the smaller 

which rxtat on its surface. These bodies, 

vicbia the reach of direct experiment, are the 

by which, in the first instance, we arc ena- 

dUcowT the chief properties of mutter. 

lifjQ of the more distant appearnnres of the 

maiTft of the universe, including the earth 

mAa OS thftt these bodies arc playing the 



same part, on a grander stage, as the most minute 
particlca of dujit which dance in the sunbeam, or 
the stilt more Impalpable atom* of air which float 
around us. The force of aa irresistible body of 
analogies, therefore, hurries os to the conviction 
that the same phyiical properties, which observraion 
and experience disclose to u% in the more limited 
masses which immediately surround us. are exhibited 
in exactly the same manner among those {o6nite 
systcroa of bodies, whirh. filling the immensity of 
space, are placed fsr beyond the reach of that species 
of observation by which alone those peculiar quali- 
ties can be detected. 

Like other physical qualities, the distribution of 
heat ia regulated by the same laws among the bodiea 
of the universe as among Che bodies which sor- 
rouud us. The earth radiates and absorbs heat in 
the same manner as any body placed on its surface. 
If there were no external source of heat, therefore, 
the consequence would be that the earth, by con> 
stantly diaaiissing heat by radintlon into the aur- 
rounding space, would be gradually cooled, and the 
temperature of all objects would fall indefinitely. 
Liquids would be converted into solids ; and gases 
into liquids, and subaerpiently into solids. Vul 
although the earth radiates beat, and thereby con- 
tinnally loies a portion of that brat which it con- 
tains, it. on the other hand, absorbs such heat as is 
radiated upon it by other bodies. The bodies of 
the universe, from which the earth in thia manner 
may receive a supply of heat to replace its loss by 
radiation, may be expressed in three distinct clasiei i 
1st, the sun ; '2d, the other bodies of the solar sys- 
tem, including planets and satellites, and the moon; 
and 3d, the fixed stars. We have already seen that 
the heat which accompmiei the rays reflected from 
the moon is Inapprccinble to the most sensible 
thermometer ; and that, even admitting that the 
reflection of beat from the moon was prnportional 
with its rettection of light, the utmost efTect nf Its 
rays, when condensed 300 times by a powerful re- 
flector or lens, would nut produce an effect amount- 
ing Co a minute fractiuii of a degree of the thcrmo- 
roetcr. It may, therefore, be assumed, that from 
the moon the earth receives no sensible supply of 
heat to replare that which it loses. 

The experiments of Professor Leslie on radiation 
lead to (he conclusion that the power of radiated 
heat from a given object varies with the magnitude 
of the object and the distance, inerensing in the 
sinie proportion as the Hitparncial magnitude is in- 
creased (the nature of the surface being supposed 
to be given), and decreasing in the came proportioa 
■ 8 the difttanro is increased. From this conelusinn 
it follows, that the cfTccC of heat radiated from an 
object ia alwnys proportional to the apparent viwual 
magnitude of lUat object. Thus, if two bodies, 
radiating beat in a similar manner, have the same 
apparent magnitude, whaTever be their real magni- 
tude, the effect of their radiated heat will be the 
aame. 

Assuming that the anrfacca of the planets and 
their satellites have the same power of reflecting 
heat as the niooD, it will follow, that the efTccts of 
these bodies in radiating beat to the earth, compared 
with that of the moon, will be In proportion to their 
apparent magnitudes. Now, the apparent magni- 
tude of the largest of these bodies ia prodigiously 
leaa than that of (he moon, and many of them hove 
BO amall an apparent magnitude, as to be invisible 
to the naked eye. It follows, therefore, if the best 
radiated lo the earth by the moon be tnappreciahlct 



J 



238 



MAGAZINE OF SCIENCE. 



thRt which proccedi from the planets and other 
bodies to the ?oIar »T»tem will he Htill more incon- 
RidETtible. Su fir, therefore, as the soUr ftystem is 
concerned, the <iin iiloite muit be regarded iis the 
mrans of rostoring to the earth the heat which it 
loses hy radiaiion. 

Alt the rriults of aitronomical obserralion conn- 
fensnce the probability that the fixed stars are 
bodies fimiUr to the sun. They shine with their 
onn light, and not, like the planets, with light re. 
ceived from another object. Their light is, there- 
fore, Tar more intentie and splendid than that of 
any planet. If it be assumed, that these bodies be 
ntnilar to the lun, we may suppose that their rays 
are equally calorifir. It will therefore follow, by 
the law esiabllfihed by Sir John Leslie, that the 
heating power uf the (ixi-d stars will be, to that of the 
snn. in the proportion of their apparent magnitudes. 
On a first view of these facts, and considering the 
intense heating poner of the sun's rays, and the im- 
mense number of the fixed stars, it might be sup- 
posed that the firmament, studded u it is by these 
bwlics, wnnld ofTer an extensive source of heat. 
Such, however, is not the fact. The distance even 
of the nearest fixed stars is so immense, that the 
most powerful telescope ever yet constructed, has 
been incapable of producing the slightest effect in 
magnifying them. In fact, no fixed star has any 
visual magnitude whatever : they are mere lucid 
points which subtend no angle to the eye. If, 
therefore, Leslie's law be applied to them, it will 
follow that the heat of solar light is, to that of the 
fixed stars, in an infinite proportion. 

NEW MOTIVE POWERS. 
A ritw years ago conniderable sensation was pro- 
duced by the appearance of a work, publi«hed ori- 
ginally in America, and soon after reprinted in this 
country, under the title uf " Paradise within the 
reach of all iMtn." Sec, in which the author, Mr. 
Elzler, undertook to demonstrate the existence of 
motive powers in nature, which might be so applied 
as to supersede roost of those mechanical and other 
indentions which society so extensively employs for 
tlie satisfying of its numerous wants. Mr. Etzlcr 
went further, and declared that he, himself, pos- 
sessed a knowledge of the means of so applying 
these powers, and offered, upon very moderate con- 
ditions, to make known his dixcoveries. After 
retMioing these secrets in his own bosom for a num. 
ber of years, it was Mr. Etzter's fortune to become 
acquainted with an individual who could apprectiite 
his views, and who Introduced them and their author 
to ceruin other spirited capitalists. The result has 
been ibe formation of a company in the United 
States, for the purpose of bringing these diicoveriea 
before the public. A patent has been obtained in 
America, and, within the Inst few days, one for the 
United Kingdom, in the right of Mr. Stollmeycr, 
whose visit to Europe is expressly for the object of 
securing the patent rights in this and other coun- 
tries ; after whidi, no time will be lost by the 
pntenteesin making the promiaed discoveries known, 
We may state. Coo, that an elaborate work, princi- 
pally descriptive of the new inventions, is already 
completed by the author of the " Paradise," ttc, 
and will be published as soon aa the above ohjccta 
ahall have been accomplished. Through the favor 
of Mr. Stollmeycr, we hare seen the models of .Mr. 
Etaler's inventions, and have been astonished at 
their simplicity, and their manifest superiority over 



every application of motive powers now knir 
We are not permitted to enter into the detail* 
these eitraoniinary improvern^-nf*, bat shall vtojo 
to sav that no one, after having seen tr^.*!^ ■- 
doubt the pnnibility of (ho results preJ 
Etxier's highly original work. The p:* 
" rertiiin improvcmrnta in the appliontion v( 
powers of wind and water to agricultural and otbl 
purposes.'' One of these purposes is the prapid 
aion of veaseb on the oc-ean. The anticipated msslla 
of the new application of these powers on 
are of quite as superior and decided character 
/nren/or'f Adroeate^ 



THE CAST-IRON LIGHTHOUSE. 

In writing a description uf a cast-iron ti|i;hthoUB 
tower just completed for the island of Jamuci, ■ 
opportunity is afl^orded for a few words on tbe sik> 
vantages offered by this peculiar mode of 
struclion. Mariners have frequently been d 
of the security aflbrded by lightliouaes on 
coa.<ts, from the great costliness of aurh s 
as well as from the danger or difficulty 
their erection, in consequence of locrfl pec 
arising either from tidal restrictions, or fr 
difficulty of obtaining foundations uf 
solidity to support the heavy mnsa of 
the tower. It is a fact of common oomrmi' 
yenra are required to erect a lighthouse ot] 
moderate dimensions, where the rate of 
limited, both by the nature of the tides and 
peculiarity of the season ; and the aothoritiM 
preside over these matten are frequently d 
from entertaining the application, for such focUldAl 
Co navigation, from the cost and trouble allcn(Bog 
their execution. 

The situation for which the lighthouse Is int«ijll4r^ 
has long required this protection, but th« gn^ 
expense of stone or brick erection, and Ibe fiat 
required to complete them, have interfifred wttk 
their earlier execution to complete the plan. 

Mr. Alexander Gordon, the engineer to the 
mi^sionera appointed to carry the plan into 
is the designer of this building, and who 
mended the adoption of cast-iron, in co 
of the snggestions some years ago of Cai 
Sfimnel Browne, and the subsequent erec 
small light tower on Gravesend Tier, by Mr. 

The advantages which iron, when not to 
with sea-water, possesses over intone or 
materials, \9, that upon n given base a much 
internal capacity for dwellings mud stories 
obtained with equal stability. The oatnre 
material admitting of the plates being cast 
surfaces, there are fewer joints, and co 
greater solidity. A system of bonding the 
may also be adopted, which will ensure the 
combination of every part,' so as to fortr 
mass, and by the facility which such a 
for uniting the parts, the best form for <i 
stability can be obtained. Tbe time required ttf 
the construction of snch a building in iron ticiBf 
less than that required for the preparation of OMn 
atone, would, in many inaunces, indaenc* ^ 
adoption, and from the comparatively small baft 
and weight of the component parts of tbe iimcttffc 
mnch greater facilities are afforded for lninspor*tB| 
and erecting it ot its destination. It is a foct wofthf 
of remark, that in less than three months frotstks 
date of the contract, the lighthouse in question *■* 
cast and erected ou the contractor's prvmisrs. «"' 






MAGAZINK OF SCIENCE. 



!39 



I w. 



t«Dtion of Mr. Gordon, the cnpneer, to 
ight ckliibitril in Jamuica, on January lit, 
tig Six monlbs from Ihe dute of its com- 
|l. This i» II (Irj^rcc of cxjKditiou com- 

wiib the rxtnioitljuiiry det|iat<;h of tlie 
%f, when all u]»riikfu>!it, howrve-r great and 
■cctn lo aiUancc with a celcnty which ■ 
back would have been deemed chimerical. 
Ipeiuea of the coQBtruction, the traosmis- 
IB de«tiiiaLioUt >ud ita final erection, will 

one-third the coat of a itone building of 
leoMont and capabilitirB ; and in locajiliea 

materials are not nnturalljr produced, but 
e traoiported from a distance in a fit atate 
^te erection, tlie eipenar would consider* 
ed thla ratio. Another prominent feature 
patruction of iron ligbthouBra, Jkc, is the 
K>ni electric iuduence, the inaterial itaclf 
I of the beat conductora of the electric 
if pro]>er means be taken to transfer the 
lid frum the base of the tower to the aea 
of copper conductora, no danger need be 
fled from ita efTccta. 

blfaotttr in question is the first of its kind 
keen practically carried out, and from ita 
withstand the deatructive hurricanes 
II as the frequent earlh(|uiike£ that 
Ibe Welti Indiei, it will afford a good eji- 
r future prartice. The form hat been 
[■• well for strength as for symmetrr, and 
■Mjneut of the Untern and light apparatus 
te greatest credit on the manufacturer, 
le. 

ircf is to be founded on a coral rock, a 
e the lerel of the ae^t, the face of which 
( 10 feet beneath the surface of the 
I which will be excMvattd to receive the 
• tower, resting on and cased with granite, 

the DBlural 6ltrstioo of the aea water 
Ig upon the iron. The coarse of granite 
£ the base of the tower rests, is grooved 
tbe flange of the lower plates, from which 
iJng conductors are continued to the sea. 
Her of the tower shaft is IH ft. 6 in. at its 
linishing to M feet nnder the cap ; it la 
fflioe tiers of plates, each 10 fret in height, 

m 1 to i inch thickness. The rircum- 
fbrmeil of 11 plates at the base, and 9 at 
ttiey are cast with a flange all round the 
(a, and when put togetlier. these floages 
joinls whidi are fastened together with 
ircw bolts, and caulked with iron cement, 
onsista of 10 radiating plates which form 
of the ligltt roam, and ifcnred to the 
m 20 pierced brackets, bring tinished by 
D rolUog. The lower |K)rlion, namely 27 
led up with masonry and concrete, weigh- 
500 tons, and so connected with tbe rock 

it forms « solid core of rtfvistnnre; the 

portion of Ihe building is divided into 
Icb are to be appropristed as store rooms 

for the attendants in the lighthouse, 
^t room consists of caat iron plates fire 

on which are fiied tbe metal sash bars 

Eng the plate glass, these terminating in a 

covered with a copper roof, from which 

»rt lightning rod. treble giU at the point, 

the electric current. 

pit is of the revolving kind, consisting of 
id Um|is Slid reflectors, five in each side of 

r^ triangle, and so placed as lo cousti- 
llinnotts ligUt, but with |>eriodical flashes. 



In order to preserve as low a temperature as the 
nature of the circumstances and climate will permit, 
the iron shell is to be Lined with a non-conducting 
maCcriil, such as alatc or wuod, leaving on annular 
interstice, throuf^h which a coiistant veotilabon will 
ht* effected, and by which the eicessive heat will be 
carried off, in which it will doubtless be assisted by 
the evaporation of the sea spray which may acci- 
dentally be cast upon it, as it will be placed within 
GO yards of the ordinsry water level. 

In order to preserve the two lower tiers from 
oiidation, they have been coated with coal tar, and 
Mr. Gordon intends to set Ihem in the grsnito with 
a bituminous cement. The only bracing which bos 
been thought requisite is a few cross ties at each 
horiiontal joint, over which the iron tongued wood 
floors are laid. 

The several rooms are provided with five aper- 
tures, fitted with oak sashes glnurd with plate glass; 
the approach to the doorway, which is about 10 
feet above the level of the sand, will be by means 
of stone steps ; Udder irons are also provided in 
the event of the stone ttepi bdng carried away by 
a hurricane. 

The whole of the costtoga were executed by Mr. 
Robinson, at his manufactory (late Bramah and 
Robinson), at Pimlico. und put together in the yard 
of the manufactory prior to their removal for its 
intended destination. 

The work will be re-erected in Jamaica by meaoa 
of a derrick and crab from the inside, without the 
aid of any external scaffolding. 

We understand that the whole expense of the 
lighthouse, including the passage over the Atlantic, 
and the erecting it on the promontory in Jamaica, 
v^ill not exceed jt7000, and that the entire weight 
of iron of the whole fabric i« about 100 tons. The 
mssonry Is being prepared in this caantry. as It will 
be more economical to send it from England than it 
will be to get the stone and work it in Jamaica. 
Three mechanics arc also to be sent out with the 
work to put it together on its destined spot.-~Cfn7 
Enffinttr, 



PHENOMENA OP GLASS. 

fTotbf KdUrrr.J 

Sir, — Having read with much pleosure an article, 
in your truly valuable work, upon the " Phenomena 
of Glass " ; and being much struck with the won- 
derful and seemingly unaccountable mystery attend- 
ing the fracture of the lube, eod Rupert's drop; 
I hare taken the liberty of hazarding a conjecture 
as to the csuse of the phenomena described,^ 
Pint: the tube ; — It would sppcar tliat the tube 
was cleaned with an iron wire, having a piere of 
wash leather at the end. Now I would a^k of you t 
is it not possible, that the friction of the leather 
upon the glass may have the effect of charging tlie 
tube with electricity, to such an extent, that, upon 
the wire coming into contact with it, it acts as a 
discharge ; the shock causing a number of minute 
fractures in the gloss, whicli every vibration of the 
air would have the eflcct of enlarging, until at last 
it falls to pieces. 

As to the fracture of the rod, my ides it this, — 
The glass in a melted state when dropped iulo cold 
water, by its great beat decomposes it, and at tbe 
ssme time immediately contracting it, forms into a 
drop, inclosing a mixture of oxygen and hydrogen; 
derived from the water, i^upponing tins to be the 
case, (on etriking two picors of gtlas together in 



240 



MAGAZINE OF SCIENCE. 



ibe dark, a spark. wiU be {ilainljr teen,) amy not the 
sudden breaking ofTof ihe cod. be sufficient lo cause 
• Binall spnrk, enough to igiiit« the gas conlatiied 
within, when an cxplDsion would take place, of 
•nfflcicDt force to break the gloss into pieces, at 
the same time it would give a shock to tlie band. 

Theie being the ideal of a Tcrjr young beginner 
la cbentitrj, I hope you will czcuae mU errors. 

OXTOEN. 



MEMORANDA. 

Keie Metallic Subatancc. — At a recent sitting of 
the French Academy of Sciences, M. Pcligot aub- 
mttted ft pnper on a new analjriiia of the substance 
called by French chemists " Urane," which had 
been hitherto ranged among the simple tuetala; be 
had found that it waa not a simple substance, but 
was a compound or oxide of uranium, and that the 
true metallic base wbi c-apable of being separated 
from the compound snbetance. M. Peligot had 
acted by means of chlorine and potassium, and, 
having obtained the new metallic substance, which 
had never before been got pure, bad found its 
atomic weight to be expressed by the tabular num- 
ber of 750. ^ 

Valnabh Diitcovery. — Recently, two inteUigent 
French merhnnica attended at the plumbers' ^op 
in the Woolwich Dockyard, to show the workmen 
and a foreniiiu from each of Her Mnjeaty's other 
dockyards, a new invention for soldering or joining 
metals without solder. The mode of operation was 
discovered by Le Comte de Richemond, who has 
taken out a patent for it in this country. The in- 
vention is applicable to brass, copper, lead, pewter, 
and zinc, and the procecs it very simple. It merely 
cousists of the application of a very powerful heat 
from a smaU tube, exactly similar to a blow-pipe, 
attached to a pliable hollow thong, woven similar 
(a a whip, but nisdf air tight, at the end of which 
is placed two stopcocks, the one to admit hydrogen 
gas. grnerated on the spot, by placing sulphuric 
acid mixed with water upon cuttings of zinc in a 
Tetsel (xinstrncted for the purpose. The other stop 
cock admits almotpberic air in any quantity and 
with great force when requisite, as it is assisted by 
8 amall portable bellows worked with the foot upon 
a pednl simitar lo those used by the glass-blowers 
at the Polytechnic Institution and Adelaide Gnllery. 
The foremeu of the various yards tried a number of 
experiments with lead, both with flat and round 
pieces, and formed joints, all of which they per* 
formed in a very s a titi factory manner, and appeared 
at onoe to comprehend the whole theory of the dis- 
covery. The joining cannot be known from any 
other part of the metal, and ninsl be a great ad- 
vantage over the old method, as it passed through 
the whole thickness of the metal, and appears to be 
u perfect on the one side as the other, enabling 
every part to bear equal presiure. 

Applicaiifm of G/fl« T^tbtK as Watfr-PtpM. — 
The Journal St. Etivnnc statrs that experiments 
were to be made on the 2nd of this month of a plan 
proposed by Messrs. Ikrgeron and Cambier, civil 
engineers, for the employment of glass instead of 
east-metal pipes for the supply of the principal 
fountain of Rive de Gier. The advantages of glass 
pipes may be easily appreciated ; the water will 
leave the fountain in the same state in which it 



entered it, without being altered 
Btopited to the pipt-s, by the eOecta 
of corrosiona, which often obstruct 
Every one knows that glass can be sul 
enormous pressure, without danger of 
We have aeen, for instance, bottles of chai 
BUpport a weight of 46 atmospheres wiihovl 
The proposed pipes then, 18 centjmetrrs i 
meter, ought to resist easily a pressure of 
nospheres. Should the experiment sucoei 
effect will be to rrdtice to one^llnrd of theit 
price the cost of water-pipes, — Le Fanal* 
Prcico Paintinp — A correspondent of 
n^um suggests the following substitnte 
psinting in the decoration of the Ni 
Parliament, which he contends will have 
beautiful effect and be quite as durable 
wall is first covered with Roman cement, 
called stucco ; after this is dry, it mi 
three or four coats of a mixture of fat 
boiled with gum, similsr to Tsmlah — in fs 
be called vamisfa, only obserriug that Hi 
crack. Tbia penetrates the cement, and 
from what is termed sweating-. Then eon 
the ground for the picture, preparing the coif 
half turpentine. For the picture itself, hsv 
colors ground in oil and work thexn in turp 
and it wiU have the same effect as fresco ps 
It requires to be finished expeditioosly, i 
colors set fast. This sort of painting, I 
say, would ouswer well : Ut. Because it « 
hard. 2od. It will reuin its color. 3nl. Uii 
to fresco in beauty and appearance. 4th. 
preparing the walls, the rooms may be 
business, and the artists continue their ~ 
such times as are most convenient, as 
little or no dirt. Any artist will be able 
works in this style." 

Fire and Hfffer PrOf^f Cement. — Pour' 
vin^^ Into a pint of milk ; when the laS 
fully ooagolatcd, clear it off the lumps, an^ 
settle, then mix the whole well together ; ■ 
into the liquid quick hme, till upon ttirn 
whole we obtain a thick paste. This 
]>crmanently unite marble, earthenware, 
— French paper. 

Temperature qf Planlt. — Nf r. Van 
constantly observed this phenomenon, in 
of his pxprrinirnts — that in suddrni; 
bell-glsES which cut off all commuidcatic 
the air of the apartment and that of the 
heat of the latter always rose suddenlj 
of a degree. 1'hia pbeoomeDon, howei 
only a few minutes: the magnetic needl 
trograded, pasbing zero of the scale, and 
by its opposite and permanent duration, tl 
living plant bad a much lower temperatui 
dead leaf, ns is always the case in the al 
Is this phenomenon to be ascribed to 
taneous access of free air to the plant, 
stimulating its vital functions, that were 
by its having been kept in a less pure air»] 
al the same time its proper heat, b^orett 
acting and friyoric injttience qJ re-ev/t 
poration hat had time to make iteeff/elt .* I 
Beck cannot venture to decide tliia : bat h 
that other philosophers and nstur&lists 
in the^e researches, which, if he li D( 
may yet throw some light upon many an 
question in animal physiology. — Gmtpte-Ro 



4th. 

4 

ourT 



bat h 

lOtl 

inioG 



LoK»oM.— PriHtrd ))y D. Kkaxck. ft. Wtillo Hnrme Lnne, Mil* End — PuliDihcd by W. Bsittain, 1 1 . PsfwaHH I 
t'onimuDleallou, ^wLich are siuwcrvd Uonlhljr,; lo tie addr««»«<l to Uie Editor. bI ST. Cottaet Cnrt, UOml 



'.MQsBy 



MAGAZINE OF SCIENCE. 



CHEAP UVDRAULIC BLOW-PIPE. 

n\< Hit Editor J 
SiK, — 1 inclose for iaaertion in yowr Magaxinv, a 
sectional drawing of a eimplc, cheBji, and cITeotiTe 
hydraulic blow-|ii|»c. The drscription is as fnllowa : 
A, Fig. 1, is a cylindncsl tin Teasel, 13 inches deep, 
and 10 inchtrs in diameter. U i* n loose lid, to 
whirh is ftoldtrcd air-ti^ht the Tciscl C, which is 
t\ inches in diumetcr, but without a bottom, and 
njipruaches to within a quarter of an inch of the 
bottom of llie former vessel A. D is a piece of 
^ iocb lesd-pipe, with a lap at the lower end, which 
eoinmanicatcs with the interior of the vessel C ; E 
U A piece of I inch pipe, which also communicates 
wiUi the vessel C ; F is the lamp ; G G is two pins 
of wire, to prevent the lid frum being liAed up by 
tbe pressure of the water when in action ; 1 is a 
lip which most be left uncovered, so ns to allow the 
air fite acce&s to betwixt the veasels A snd B. 

Tu use the blow-pipe, take ofT the lid and 
nearly half till the vessel A with water; then put 
on the lid, nnd fsslen it dovrn by the wire pins G G. 
Put a g1«B» nozjile on the pipe E ; open tUr tap, nnd 
blow down the pipe D, so tu to force all the water 
out of Ihe vessel C. Then shut the tap, and you 
will have n steady strr-am nf air for about three 
minutes, proridiiig the orifice io tbe glus aoule be 
not too Urpc. 

A hlow-pipc upon iliis plan will be found very 
tis£-ful in ever;- little Inhorjitory for many purposes ; 
by merely taking ufT the lid it forms an excellent 
vessel for holding^ water ; it may also he converted 
into B pnruointic truti^h, by soldering three small 
tin brackets, about 3J inches from the top of the 
vessel A, so as to support a moveable tin shelf. 

IThe abore li to very ilntitn to 1h« hytlmuUe blow- 

[it|Mt of Mf . TiHey, Ihm wi- hove ruhjoicei) n ciil of tJk» lulU-r 
■Htruntvnl, V\i- >. nlvo. A to tti« oulnr vrwsrl wliU'li ■« Mjuuri- : 
II a (UvlBtiu acrou. W.V Uie m:»c ai In Mr. Sliar(>)ti'i 
tnilrwncBi. — Ko. } 



ON A MACHINE FOR CALCULATING TIIB 

NUMERICAL VALUES OF DEFINITE 

INTEGRALS. 

■T TBOFCSSOn MOSBLEY. 

Tt is the object of this machine to apply to the 
numerical luilrulntion of definite inrx'^rrals, d prin- 
ciple first MU^rsted by M. Poncclet for the regis- 
trarioD of dynaniometrical admeasurements, which 
has been applied by M. Morin to an instrument 
ojdled the comptenr, for registering the traction of 
loaded carriages upon common roads, and during 
the last year by a committer of tbe British Associa- 
tion, to a permanent registration of the work of the 
ateam ujuin the piston of a steam-engine. Tlie 
innchini* about tn be described has some inerhsnical 
expedients in common with the last-mentioned ma- 
chine ; it has nothing iu common with tbe compteur 
of M. Morin, except the admirable principle of M. 
Foncelct. Id tbe accompanying figare, D E reprc- 
SKntA a circular disc, moveable about an axis C, 
pu^^ing through '\U centre by means of an endless 
screw, working in teeth cut upon its circumference. 
Q U K L is a rigid frame, composed of two rods, 
Q R and L K, joined by cross-pieces, Q L and RK, 
and moveable at itn extremities about axes whose 
centres are io a straight lioc, passing through the 
centre C of the disc. The axis A uf this frame is 
AoNow, and there paeses through it a rod V T, at 
the eilrttmity of which is a wheiil SP, which, from 






Uio peculiar fanctions ftstigned to it In (bis machine, 
is rsllrd the intttfratiny wheel ; the wheel U rann- 
bIjIc about thci extremity uf th« rod VT, bat is 
coiitiiird to it by means of a nul, and it ha* h<tfci 
in two of its aryis, through whwh the rods Q R cad 
L K of the frame pass, fitting them Ar<nif«t»Jf. 
The axes of Ihe frame turn to bru. 
not fixturrs ta the frrmc of the ; 
which slide vertically by meri^- ■ ( 
fixed pieces A B and G H. '! 
and of the wheel S P is thui- 
npon the point of contact V nf the edge ut 
with tbe disc D E, and any amount nf 
the two surfaces of contact m«y be o' 
sufficiently loading tbe frnroe. The rod I 
nected by meaus of a vertical piece VI. oiui i 
accond similar rod UZ, at whose extremity Z it k 
short vertical piece reaching to the «urf»r.> M 'Jm 
disc, and kept pressed against the can' 
rail E F (which is screwed down upon - 
and is of any given geometrical form), tj j i l 
a cord attached to the cross-piece V IJ, »ir 1 jr:-. 
ing a weight. It is evident from this 
lion that, if the carve E P be any otii 
circle, having its centre in C, the wheel 
made to altpr its position on the frame QB, ind 
the point P ira distance from the centre C, by 
pressure of the edge E F, when the disc or 
E D is made to revolve by the action of tbe 
and that the geometrical law of this char 
tion, in reference to any angular revolu'. 
disc, will be dependent upon the polar nyi^i 
the curve £ F. or upon the rebition of its radbu 
vector C Z, to the angle which that line msiss «^ 
any other similar line given in position in it. Not 
let it be conceived that such a form is gives to tl0 
curved edge E F, as to cause the distance CP«f 
the point of contact F, of the circumfexmor of tha 
wheel S Pr from the centre of the disc, wbidi ifil» 
tanco diflers very little from C Z, to be a {pnA 
fanction F (fl) of the angle ^ described by the 4bt 
£ U, and let it be observed that, as the wfaed Sf 
is made to traverse the frame Q K. by th« pmcanflt 
the edge or rail E F ; this wheel is also mode to ia> 
volve by its friction upon the plate at P, that frictta 
being produced by the prtssRure of the weight of ths 
wheel and of the frame U K upon tbe pbte, iibidL 
pressure, if il be not sufficient for the purpose. msT 
be increased in any propoi-tion. The wheel Sr 
thus continunlly varying its distance from 
centre C of the plate, and its ctrcumferenca 
tinnally revolving with the velocity of that 
the circnmference of the plate with which it is 
in contact, It follows that the number of revoltttloi 
and parts of a revolution, which is made by it, nl 
therefore by tho frame QR. which it carries witk Uf 
OS the plate revolves from any given angular ptrf* 
tion 9,, to any otlicr, 9,, is a funclion of the fcm 
and dimensions of the curve £ F. 

Let now a contrivance be applied to the 
mcnt for regiatering the rerolutions N of the 
Q R K L, and therefore of the integrating wheeU 
to the 1, booth part, or to foor places of de< ' 
This registration may be made by the co 
method of astronomical instramcnts ; or more i^s* 
veniently, and perhaps with sutBcicnt accarac;,^ 
means of a toothed wheel Axed on the axis oi ^ 
frame, and running into a pinion in the proportim 
of lU to 1 ; this pinion carrying a wheel whtcti rv^ 
into a second pinion in the same proportion, K3|* 
on through a train of wheels and pinions, eschv^ 
of which being divided into tO rquil parts, «Bd*>** 



MAGA2INR OP SCIENCE. 



243 



ihow one digit of the deciouil |urt of ■ 
Dp to as innuj pUcn of deciinnU u<* llirrr 
TUc complete rcrolutions of the frame 
e uiimncT be r«'i,'i»tereJ by mcnn» of a 
the axis nf the frame running into o w^eel 
ortion of I to 10. The v^lue of N may 
ttered to four plAces of dedmala probably 

connectrtl with the endless screw which 
Son to the plate, there be ii train of wheeli 
the ipBce dncribed by a point id' the 
I distance unity from tt.H centre to three or 
of dccimais, nud (he plite be made to 
hom the position in wliich the yiven raditig 
llncides vrith C 1' into a position in which 
of the first register showa any No. N, then 
iecond or luit-mcntioned register ihow the 
9, of a number one greater than that. So 
tia aiijustment of the apparatuH, it may be 
|repl-ice n tabic of ordinary logarithm*. It 
better, however, vritb a view to this appH> 
it, to rrplnoc the plane ()i«c D E. by the 
r « cone. The rer|iiiiiite spiral would more 
r traced on the surface of such a cone; it 
ftl with the natural tpiral, traced oat by 
ilatioas of a large clisa of turbinated shoUs. 
Ikifl form the instrument might be brought 
Bmpamtirely amall compass; tod it is not 
^|o see tbnt by a mechanical combination of 
complrxity, it might be made to i^AA or to 
the lo|;aritbms which Ic registers, and to 
e aumAerj which correspond to the loga- 
Bums or difTerenoe* which it thus obtaiiu, 
bgio this procesA the tuechanicai operations 
dtcatton and division in res)>ect to numbers 
ber of digits. The only eiamplcs hitherto 
\ the calculation of this machine, are ex* 
thich lie vithin tho compoja of the ordinary 
fi»f aaalysia; ami, in respect to these., the 
could only serve to rejtlae^, perhaps con- 
^ bat still less accurately, well known pro- 
iT analytical calculation or tables already 
There i^, however, a large cln<is of func- 
■nalytical integration liei beyond the 
reaonrces of ro ttbemstical scicu :c, the me' 
infej/ralioH of which this msohine will 
rendily efTect. The accuracy of tlic 
r^ves in respect to tbf-se, being dependent 
SArae principles as the ancnraey of the 
gives in res[icrt to the others, and, there- 
HtfAed by a comparison of these last results 
tJiMes. It is impossible, in this popular 
} discussion of the suhjivt, to f ntcr at any 
r with any system or method, on the con- 
B of tills class of integrals, and the re- 
of mechanical integration, which the ma- 
in respect tu them. 
the roechnnical difliculties which present 
I to the conAtru(*tion of sach a machine 
Honing: — GiTat ut curacy will be required 
\ their true ^eotnetricjil forms to the curves 
the revolving pbte. It is unquestion- 
■ certain nmount of error must always re- 
9 to iuiiC(--anicies of workmaniihip in the 
these curves ; neverthflcsi! to those who 
ioted with the wonderful education of the 
touch and the skill of hand acquired in the 
ii&hip of some pror^sEM of (ho arts 
of type-founders* dies fur instance, 
of micrcmetrical lines on gloss, ninny 
movement 1 of m.irhincry, and tlie ad- 
tools q( Mr. M'hitworthi, it will not np- 



predaion 

that (me 

i-:o- 

ist. 

.....uig. 




pear imposi'lblfl to reach, with tlie rrquUIte ewe 
Aiiit pnticm-i-, a very cf>rt>idcf:ii 1 
in this ^e6l^cct ; nnd lei U !«? r- 
type or model bcini; thtts nti i»n. ii, it 
duccd infioitrly, and with perfect a*- 
ing in type-fuunJrrb' iKctal. or pcrh., 
or by the electrotype. A^jitn, the diffirully uf con- 
structing tht'«e can'es will, no doubt, in s'.>me degree 
be enhanced by Ihe fact, that the guiding curve E P 
must be dilTerent from what It would be if the points 
Z nnd P coincided. This dilliculty (not in itself 
considerable) may, bowerer, wholly be removed. 
We h^ve only to take the curves from the plate 
D E. and to place tbeni on iinother circulir plutc 
parallel to and concentric with D E, of precisely the 
same dimensions, but so far above it as tu clear the 
integrating wheel S P; and then to give to the con- 
necting piece V U a direction upwards instead of 
downwnrds, ao thnt the bar U Y Z may pass In the 
suprrior sarf.ice of the upper pltitc ; if this bar bo 
then precisely of the length of the arm VT. the 
poiut V will be mide in describe a pith on the 
lower plate preoisHy sImilAr to that of the point Z 
on the upper. And let it here be observed, that 
there are some important applicattcns of tbr instru- 
ment, in which the curve E F admilting of an easy 
mechanical description, the guidance of a mil inny 
bL' entirely diffpcnsed with, the point Z being mado 
to vary its position accurding to the required law, 
by some more convenient or more arrrura'c mecha- 
nical expedient. In eonclasion, let it be observed, 
tliat since by milling the edge of the iiitegnttmg 
wheel S P, by malting the plate D E of a soft metai 
— brass, for instance, or perhaps ainc — and liy load- 
ing the frame, any dcgrrc of friction of the surfaoet 
at P may be obtmned ; nnd by increasing the dia- 
meter of the wheel S P, any leverage of that fric- 
tion to turn Uie machinery connected with the fnimet 
it would be quite practicable to introduce thos« 
mechanical expedients into the train of wheeU 
whieh arc neceasary t» cause the di:;it» <.>r'llie nuffl- 
bcrs regialered to arrnoge tbemselves *iWp btftith in 
aline; and that then, by uniting with it the ad- 
mirable cDmbinallons of Mr. Cowper's iiriniiog 
press, the machine mujht he made to firint off the 
results of its ralculAtions, precisely as by the same 
press the successive numbers are made to print 
themselves U]Km bank notes. 



STEAM AND THE STEAM KNGINK. 
Wi now commence a scries of papers on the history of 
the steam engine, luttuding in the c jursc of thriu to 
give representations oiid descriptions of all Ihccelc- 
brated engines, which have, from lime to time, bwii 
invented. To understand tliis difficult snlijort thw 
more reailily, and to prevent as mu.n ''in- 

terruptions in the course of onr int , wo 

have thought it advisable to otfor 'u .-.."..;; re- 
marks on the nature of tUam itself, as a ppclimiiiarv 
knowledge necessary to beconRtJintly bomt- in miuu, 
whether in appreciating the contrivances of diilbrcnl 
inventors, in understanding the peculiarities ot each, 
or in applying tlie fuiidainctitjd principles of 
science and experiment to ihCif legitimate and usefttl 
applications. 

When water, exposed to the prc«uiT of the aU 
moapherc, is heated lo the lempcnilore of 212°, 
globules of steam, composed of heat and water iu a 
state of combustion, are formed at the bottom of 
the vessel, and rising tlirougU tlw fluid may Iw col- 
Icclod at the aurfoco. In itj ^icrfwl ttalc it is trans- 



9H 



MAGAZIKE OF SCIENCE. 




pviCw, mhkh ta merely ■ glaaa llaftk, wUb &1 
to tfv tad ft piitoo wiUiinside ;— 



tai the PQiMNntly. 
' toptas. The 
ftvB s oofliog bqiud is 
mhI to die pntotoc aadcr wluch it is produced. 
'Am itoBto nitod frato ««ter ift 212°. lod tberdoce 
«f ISA. oa the vijture inch, is 
Sic force whkh woold exert a 
«f Mj TBtoalwUcbooitfiiiesit, 
•ll* «Ml&l»Ultt.OD the aqjHn lacks toAwM thu 
^«iiy h pnHed ^r <^ ilMniylii cztanMDr, with 




to ool- 
^yoaytomliiit b«l if tte Mm W Nfcvd to 
«nk bitev tir. H vmU b« oMmrtid nto mter, 
Ml te Ikb Md Mfti oonpT a «pic« 1728 timet 
Im Itai ft dU « MMB ; > HMjBMi wwJd tfacnfece 

wmU, if not rtrj 
Oa tW other hud. 
iter to be iocreucd, 
aad ita cUstidty 
katstoml pm- 
■Pitonr or Utcr, 
tW i ULH —id pres. 
Ml toCivHcdtraipavtare, 
Hh H te k««a Uft«* ■limi|ii> tbaft M » nadcr the 
■III— m of llM HifnthTf oalf that votor boU> at 
fiV* of iMt t Wl ir It bvro » prMMCV U aecuma. 
Irttd aimn ohow it. U will ihH boU until arriTnl at 
!• «nttlat hmL. h K-Ulow*. tlicrrforr. that the tem- 
] -^UTf aw d g p ^pda m upon each other. 

ot ibMO. Cho other con be eaaily 

ti 1 .ft thi* priadple which ta alwari to 

|it> t»Mtm- In niliut when (rrfttius of the stetm en- 

«|ii»i. ami i'alpitUltniE lU working power ; and Dr. 
I'uIIioIhii ]ui» illualrAltd it 111 a trry pleuins nud 
[|A*ltui'llvu iiiaitnur. by niciUii of the fullowing ap< 




tj:7Si2i 




If a spooofal of ether or a little water be ri 
fai the bttlbof the flaak, and the bulb bdd oi 
flanw, the oontJUDed liqaid will aoon boil, and i 
•eqveotlf throw up eteam. Remore the flask i 
the beat, and ineert tiio ptatOBr vhoi it wfll belb 
that, as the steam coodauee, the piston will i 
down the tube, acted npoo by the external pm 
of the atmoepherv. If now the flask be heU < 
the flazne a seeond time, steam will a|:ain beforn 
end iti elieticity will increase, nntil first it wOl 
qotre the same pressure ss the atmosphere, « 
the piston will remain statJoDarr; afterwanfa 
internal preasnre win become m great ai to drift 
the piston. Now nippose the area of the croas i 
tioa of the piston to be exactlj l ineh, the prcsi 
of Uie BtBUMpbere upon it woold be 15 tU. If 
pressoreof Oe steam withinside be also ISIU. 
would be Hid to have a preasnre of one ctmotplU 
a 30lba. a preanre of f»o aimotpkertt: and M 
for greater araoonts. It is by no means neom 
to hare an apparatus to aseertain the amool 
pressure at all times ; for, as it has bean belhn 
served, this is dependent upon the temperatnre 
the water in the boiler, each augmentation of t 
prodncing an increase of force, acoonling to 
foUowing table : — 

Steam al a 

212° Pahr. exerts a force of . 

2i0« 

260" 

270^ 
2»<C 

300* 

310" 

320" „ „ . . 

Steam of the same dastic foree as ttie atoMMnhi 
pressme is called low prtnure sfeom, no pi^M 
above that of the atmosphere being OFcejeary 
produce it. Steam of only a few pounds fwoB 
upon the inch aboTe this, (sajr 5 or ti,) is alsoaJ 
low preasnre steam , but of a g^reater elaalidtr ll 
this it is called high pretturt tieom, 

A Tery neat apparatus, called the AipA prMM 
koiier, ahows in s very lucid manner the propsri 
of steam when under more thsn ordinary pion 
A is a strong brass globe or boiler, filled pil 
with water, B is n long nnd strong glass tube, Op 
at the top. paasing air-tight into the upper psff 
the boiler, and eztenduig to within a very ihoiii" 
tance of the bottom of it. There is a scale 
cote the pressure in atmospheres behind \L. 





MAGAZIP^rc OF SCIENCE. 



245 



irr. ihc bulb of which is withiaude A. 
:k or pipe, to suiTer the itoun to escape 




required. D if a stand for the boiler, and E 
ll lamp. When the wuter at A ia made to boil, 
liperuture, and that of the steam above it, is 
■ed, as is indicated by the thermometer. At 
me time the prewurc of the Pteam upon the 
drivea it up the tuhe B, the end of which dips 
ttie surfucc of the water in A. The height to 
the water drivrn up B rises, and consequently 

r, will be shown by the ttcale behind. 
fTobe cotUinuetLj 

THE COTTON PLANT. 

fBentned/rtHnpage 231, anJ conclude J 

ihrub which ^owi wild In many parts of the 
Indies, especially in low and marshy (;rouuds, 
rough black seed. The cotton of this is in 
a pale red. and is of so short a fibre that it 
t be Bpon; in consequence, it is scarcrty worth 
onble of gathering, and wbst htUe is picked 

us«il for ituffini; mattresses and pillows. 
g other vsrieties, the Brazil and the Guiana 
• brar the same kind of seed ai the wild 
a, differing sliKhtly in shape; these are both 

alike as to the quality of their produce. The 
« is, after the " Sea Island cotton," the most 
led in Europe, on acconpt of its color and 
•a, aund the length and strength of its staple 
bra; it is likewise extremely productirc, a^ it 
bes two gatherings in the year. It is farther 
4c as the seeds of tliis kind cungtumernte, or 
B ftrmlj to each other in the pod, and are 

■rpvated from the cotton. Tliis variety re- 

a moist soil, sDoh as generally predominates 
(cU Guiana. 

1 Indian com has a dark brown seed, streaked 
ilack ; this cotton is very white and finer than 



that of Gniana, bnt not so prodactire, Six other 
varietiefl bear nearly the same description of seed, 
among which is the Siam so noted in the Weat 
Indies, as being nearly equal to silk in beauty and 
fineneas. It is of a brilliant whiteness, and its 
fibres are very fine, long, and elastic. This variety 
produces twice in the year, bnt does not bear a 
great quantity. It is not much cultivated, because 
it cannot be cleansed without extreme difficulty i 
the seed being entirely covered with a kind of green 
moss or hair, cannot be separated from the cotton 
by any machine, ind doc even by the band without 
much labour and care. 

The cotton of Cura^-oa and that of St. Domingo 
have small seeds, the surface of which is thinly 
covered with a few short hairs or a thin beard. Thla 
kind is of a very tolerable quality. 

The seeds of the Jamaica cotton are perfectly 
smooth, bnt so brittle as to break in the process of 
separating them from their downy envelope. The 
fibre is coarse but strong, and this would be con* 
aidered of a very useful quality if it could be belter 
cleauaed. Little or scarcely any cotton is at present 
grown in Jamaica compared to the quantity which 
was produced there a few years back ; but it was 
always considered as one of the worst cottons in 
the English market, in consequence of the planters 
persisting in the cultivation of a species which could 
not, without hand labour, be properly diveatcd of 
ita seed ; it was always exported mixed with pieces 
of these, and was therefore known by the technical 
term Jbut cotton. 

Of all the speciesof cotton the snnual herbaeeoas 
plant yields the most valuable prodoce. The " Sea 
ULnnd cotton," Importedinto England from Georgia, 
bears a price double to that imported from any other 
country. The , Persian cotton has long been cele- 
brated for its BQperior quality, and the concurrent 
testimonies of many travellers show, that where thii 
species is cultivated In other ports of tlte globe it is 
equally ejicellent. But the additional labour and 
consequent expense attendant on its cultivation, aa 
well as its not being equally adapted to all soils, 
afford perhaps sufficient reasons why it is not more 
generally adopted. This speciea is cultivated In 
China, but not in sufficient quontittes for the home 
consumption, u they import this article largely 
froDi India. 

Thicjqaantity of cotton which each plant yields ta 
as vsrious as its quality. Accordingly, there are 
scarcely two concurrent opinions to be collected on 
this subject. The average produce per En|E;ltnh acre 
is reckoned by different writers st various quantities, 
varying from one hundred and fifty to two hundred 
and seventy pounds of picked cotton. 

The cotton-plant will grow in moat situatloai and 
soils, and is cultivated with very little trouble or 
expense. According to Humboldt, the larger spe- 
cies, which attain to the magnitude of trees, require 
a mean annual temperatare of CH" Fahr. ; the 
shrubby kind may be cultivated with succeas under 
a mean temperature of 60° to 64°, and may tbere> 
fore be propagated as far aa latitude 40" This plant 
it indeed cultivated in the neighbourhood of Astra- 
can, the latitude of which is 46°. Some speciea 
flourish best in the neighbourhood of the aea ; 
others again are injured by this proximity. "Die 
Pemambuco cotton, which is the finest in Brnxil, ia 
of the latter kind, and the planters find that in pro* 
portion as they recede from the coast the quality of 
the cotton is improved ; they are. In consequence, 
every year penetrating more into the interior, and 




M 



SCCEKCE. 



«MK k» ff^m ffm cut rvm witk iW 



«PBB ycania Ml «r 

ii tkere<ipre gwcnllf diH i&ii| 

IV Mod* Biiy VMaBy be prrtetfi 

mm m dm* 7«o» Int in aoaie rsn.- 

tf W pfaa^ ilaoiC la aooa as tK^;. 

■nc M food for e» 
to<^iM • IftHite oynaBd frow ttcH vtiA I 
^■Mf AMrtfe p«r|i«H. 

tka mmmI pbflil b nUnU^ te ta» 
«r ■ Aat Jwt iuiiilW J x onlj ik>i la 
» B^ vdb iM pat iato (he bola, m4 

If 




BWaMnvrti GIB 99 J^mtttr^ru in 

•a ■«. Out Iha 

*It 'Alft ma m 

ta ilji rjn-iiiir , n u 

I apOK4 to Uic Jku vf 



INGftAVI>MJ. 



u IKWiiVk yw the 

lone rkpoMH !• Ac 

r«-jly for pthtrtajf csp»J « t]M^ k«t oT cW *7. 







tl»-o Jcuched froB U« pod, .ad f.lli.iff to ihi 

OMMMilcd Md 



illiii^ hi -_. 
detcrioraUtU 



K ■ dtti f«t of Ifa process :^ 

i piMk ■» W pU MI lJ U tirfui.: JtATjii 

nlit il M nfte dK berderia^ wxx mrntit 
tn. ittd toik H Im- a few minntra 
pwkatStj beeotne «oft. ki 
!■ aw « pwrtiM is to b»taln«i vp br tl<<. \u 

«■■< late • !•■{ <tjliadi i . half an i 

wal^aa •■Tpart «f tbr 

«aK la Ite lak li^kd. vbicn a^ : 

aM «tt Ikt tlMBfc aiut ftu. 

WaaaM Mad ^ aboot hrii 

rflfe ftec ad W pre 

b 

3i AaS asc be abke to eaetpc 

k m adttwfch to aakr a tip to 

aif Ibaacad nararaa^j aftenr&rJi. uUca: 

Tba boBf Radf . tb* avtbt WMn liave hf 

^aagarfib arid, to nbMi be riit put f4 

iSmm M Bfaeb water ; tbb ou^t tn make ■ 
a drop is pUrtrd 

«f c«tV«r il sitaU bepa to «ho« an a/.ti.3n I 
a a aiinute or two. by ihroi 
of $aa ; if it arts in )rM time It 

wM be ape to break tip the ground Brnandl 

lad Bake tbem rvogb and uarv 

to ad aatd a later period, tji- 

baaarttid. More watn- •^'- ' 

V«qaiaa» beeox added, rt-i 

fade. It irill be convenb 

wanted fur ua^, iuCo s ctip ur b<»tn. 

acidt provide a jog of woter^ a |iioa 



^« 



MAGAZINE OF SCIENCK. 



247 



qnill with ll:* feather on. N'nr set 
-- ^Vf* pltip nn an exnttly lUt 
il iiito it cniitf uf Ihe diluluj 

i< - ft qunrtftr uf an inch deep. 

/Qpon the exiM)>tL*iI liDes of the coj'per, 
in Away beneath the surfnce, forming 
rbleh are afterwards to be filled with 
ink. Now the rhiff difficulty ii to 
the pUtc is fltifllok-ntly bitten, thnt the 
t nrithcr loo pate nor tnu dnrit, and the 
increased when some of them are to be 
t obade from others. 
mdeavour to remove some of the diffi. 
Hdcring both cases; first, — where the 
be all of (he •ame degree of tint. It 
PBat)y observed, thnt biibblrn will snon 
»ri»e from the ezpoMd copper, when 
omr trt be of the size of the heads of 
Dr grniiLs of ccnne sand : they are to bo 
ireftilJy with the quill, A second crop 
id afterwords a third, Ac. ; these are to 
in like manner, and when obont four or 
crops of bubbles have arisen, it may be 
lui tlM plate is done enough ; the acid 
to be poured otT, the plate washed by 
te of the w«ter of the jug upon it, and 
D the ja^, nnd then the pLste dried with 
paper. Holding ibe plate up to the lighl 
lorisontaJ position, the Uncswill be seen 
id BD experienced eye can judgo Inime- 
Ihe aapect of them, the result of the 
|ld whether a second application of the 
paary or not. Supposing the plate suffi- 
hdf tbc bordering wax is to be taken off 
Bo cleaned with spirits of turpentine, 
[it with a rag. Then rub over the whole 
$ Tcry slightly with a piece of smooth 
Itl and oil, ill order to take out anybnrr 
pmatn upon the lines, and arcerwarils mb 
pe manner with tbc oil rubber and oil ; 
boe, the plate will be ready fur the printer. 
KOt gradations of shade are required 
pg, more care and trouble are requisite. 
f.place, it is required to bite in tbc faint 
I is done by pouring the acid on to the 
L but atoppiug the process earlier than 
rwbole plate being thus fisintly bitten in, 
I poured oflT it, is washed and dried ns 
unended, then a little Brunswick black 
i brttsh, and the parts which nre to rc- 
bit are painted over with it, to preserve 
lirtber nrtion. When the black is dry, 
Dd, will be in five roinatcs, the add ta 
i second lime for the next shade, the 
Eng again fitopped and other llne^ painted 
fjjed out, as ic is called ; a third appli- 
t acid mny be osed for those lines in- 
I the darkrsl. The plate is afterwards 
It the former instance. A third case 
h which it is desirable to have a regular 
ihsde from one part or side of a picture 
to aooompliah this, pour the acid over 
■te, as before, snd gradually hold the 
BB edge, BO that the acid may leave the 
I that part Upon raising the plate 
the acid will gradually run off, biting 
''ong as it is siitftircJ to remain, 
s of re-biting ; of repairing wom-ont 
correcting false biting, &c., will be 
a separate paper. 




VEGETABLE CIRCXLATION. 

rTa Ike Juttior.j 

Sib. — If Ihc following obaerrations on thcv^etable 
circulation, &c. arc worth publicity through the 
rardiun) of your very valutble, wldely-circolatbg 
jouroal, tbey are at your service : — 

Tliere nre. at present, three sorts of droolalioQ 
known to take place in vegetables ; these may be 
divided into general and partial. The gnterai cir. 
culation we most allow to be the moct important, 
viz. : that commonly denominated tlie circnlatioa 
of the sap, (althoogh one circuliitioa is aa much 
that of the sap as sny other, aa all unelahorated 
fluids must be iucluded under tlte term sap.) This 
commences in the extreme roots or radicles; we can 
easily imagine endosmosia to be the cause of this, 
as the sap within the loose cetluUr tissue of tlie 
radicals must be of a greater density than the fluids 
without ; it then passes up the woody tissue and 
ducts of the root, and entering the stem ascends 
by the last formed layer wood, or the albumam 
(sap-wood) ; it tlien passes along the upper layer 
of vessels and woody Abre oomposing the petiole, 
or leaf stalk ; then through the corresponding rami- 
fications of the petiole, fonning the superficial layer 
of (lie network of the leaf, to return by the under 
surface, where it is exposed to the influence of the 
atmosphere, and where it parts with a considerable 
quantity of moisture ; in fact, here respiration talus 
place, it then returns to the stem, and descettds by 
the trunk and the cortex ; during its ascent and 
descent the fluids are diffused laterally by means of 
tbc mcdallary rays, so as to form a commnoicatioD 
between tJEio centre and circumference of the stems. 
It is now readily understood how the elaboraliuo or 
perfection of the sap of plants takes place, so as to 
place the peculiar secretions, characteristic of the 
species, in the bark, or sometimes through the 
medullary rays in the duramen or central old 
wood. 

We have examples of both these constantly be- 
fore us ; the medicine commonly denominatt-d Inirk 
is the cortex of a species of cinchona ; the 'guaia- 
cnm, or tigngni vitto, osed now so abundantly in the 
decoction of MfnaparUla, is an example of the 
elaborated juice residing in the heartwood. It haa 
been calculated that f of the moisture absorbed by 
the radicals is given off by evaporation before the 
complete perfection of the sap. After the sap lias 
deposited various parts of composition in the lis«ne 
of tbc plants, a portion is returned to the radicles 
and rejected, similar to the excretions of animals. 
This fully explains why 6oe plsnt will not grow 
where another of the aarae species thrived before 
it ; it also demonstrates the necessity of efaanging 
the mould in flower-pots occasionally. This species 
of cifoulation cannot be observed by the microscope; 
it is principally proved by cultiug the stems of trees 
in the spring, when the sap first begins to acoend. 
when ic ia observed exuding at the cnt surface of 
the alburnum ; also by tying ligatures firmly around 
stems, when the portion above the ligature beconua 
excessively enlarged from distension. 

The first Bpecies of partial or special circulation 
is denominated eyclotis, and takes place, or rather is 
said to take place. In a set of vessels denominated 
laticlfcrouB, from conveying the contained fluid or 
latex. ]t was first pointed out by M. Schultz, but 
I have myself never been able to observe it, nor to 
obtain its vessels. They are said to differ from the 
other vessels of vegetables by anustomising freely. 



I 



248 



MAGAZINE OF SCIENCE. 



and by their CAlibre remaining undiminiahcd ; it 
U taid to he exceedinglj rapid, and t« to be found 
in thoac pianta containing a milky^ or colorpd joice, 
ts Ch« euphorbitB, or celandine (cbelidonium). Bj 
■ome it i» said not to tuke place in peculiar Teasels, 
bat in Che intercellular Bpacei ; but I have no doabt 
myaelf that it doea not exiit. I beUere the rapid 
flow of the aap (aa demonstrated to me once by « 
believer.) to take place from mptured tcskIb or 
cella ; it always takes place in one direction. 

The third la the moat distinct, and best obaerred 
by a microscope, it ia called rotation : I have do 
doubt that this esista in nearly all vegetable cellular 
tlstae, but it is rery easily put a stop to, and there- 
fore it is with great difficulty seen in the section of 
•temf, &c. It is usually said to be best seen in the 
dura. The genus cbara hu been subdivided into 
two, one retaining the original name, and cha- 
racterixed by the cells being spirally corered with a 
Layer of smaller cells, and nitella, characterized by 
tti« abwnce of these spiral cella. In the former it 
is neceanry to tcrape the superficial cells off before 
it can be seen. There are three modes of simply 
showing it: — first, by a live-box, a portion put 
with some fluid in this is the simplest ; or second, 
in a smalt phial or tube; or third, between two 
piece* of glus, winding some cotton round the two 
ends of one piece before laying the other upon it, 
to prevent pressing upon the plant ; when the glasa 
tube is used, it is necessary to have a cylinder per- 
forated at each end, or something to keep out the 
lateral rays of light, or to prevent aberration. An 
infusion of opium has a remarkable cfTeot in stop- 
ping the circular, showing that it dep«nds on some 
vital prcM»s8. The simplest mode of seeing the cir- 
cular (bat one I have seen nowhere described, it is 
mentioned byMeyen,) is in the radicles of the frog- 
bit ; the stipules arc usually employed, but they re- 
quire a very high }>ower. 

Now in the radicles a halMncb focal lens will be 
sufficient, and it is the most satisfactory of all, for 
the nradets ara perfectly transparent, and it is 
bcantifolly distinct j also, it appears aa if there 
were an oblique septum dividing the cells into two ; 
from the peculiar arrangement of the currents, they 
■ometimes appear to cross one anothrr; the cells 
here are sometimes jointed, but mostly single. 
There are two motions de«cribed In the rotation, 
one of the fluid within the cells, and another of the 
Boating particle, or their axes ; 1 think there is no 
doubt that the Utter is purely accidental, resulting 
from the collision of the particles against each other. 
The circulation can alio be observed in many hairs 
of plants ; in the scnecios, Ifcc. 1 may perhaps just 
mention that abundance of chara (the true chara*,) 
can be obtained in some slow streams, at the foot 
of the field beyond the church at Northflcet, near 
Oravesend; I have obtained it there myself.and have 
it growing beautifully along with nitella from >A'het> 
atone, near the turnpike. j. w. o. 

* Our Coiri.>s[>endent sticalii or the true cbari. he mo&ai 
that fpsoici whk-b li Iml nddplnl la RhbW TVgeUbl? rlrralB- 
li«a. Tbera ar« elKht or alne Bpeciei of tliU plnnt. af iintli-li 
fTDWth. All of Ihcni an suhmcncfl wstcr planu, wtlti a 
throad-Uke H»m. and ihrrsd-hka brancbM, growing from Uta 
■lem to » whirl, tltftt it, ■inidar Iv Uir nln of to umbntlla. 
Tbvrs are no l«avira, nor tlower*, inmt of tbo Bpocio aro 
oovcKd wltb a Iblrk emit ur lime, bui llirr« nr» four per- 
fectly tniiui>Rr«nt uid iniootli : charft trantlucetu. tlfKlhi, 
nldtki, ftsd (Tarilla Tbn Arst U tttc moit romnioii, •ml U 
that abova atfoded la Bendo Ibe abova givva italioDi. U ii 
aboodant In powb ofar Totlendgc.— Eb. 



TO EXHIBIT THE M.\GNET1C 
AN EASY AND SIMPLE 

CTatht EdUar.j 

Sir,— I would most cheerfully ooai 
pleasure and instruction of others vhi 
in my power ; if, therefore, the following 
should be deemed worthy of insertion ia 
luable pages, it is much at your service. 

Possessing a steel magnet, say of 
steel plates, of a horae-aboe ^ape 
similarly shaped horse-shoe of good, 
of about i inch or f in diameter. Ro 
or poles of the said iron horse-aboe, 
thirty or forty feet of copper wire, cots 
cotton, {fMe irire mai/ be of the tiie of te 
in the shape of two stout coils, letting the 
the said coils project ^ inch beyond the eod 
said iron poles. Now let the steel ^ 

to the iron one, attraction of courae 
suddenly detaching the two 
clean bright ends of the coils 
magnet, and a bright magnetic 
ensues; perhaps on illustration 
better idea. 



ice, 

i 



A A, steel horse-shoe magnet ; 
to ditto ; C C, the bright clean 
coils, resting carefully on the ends of 

Permit me to say, thst I have with 
paratus elicited the magnetic spark 
magnet of one bar only, whose lifting 
scarcely one pound ; the above is aa ^ 
my own invention, having never seen 
in so simple a manner before. 



PHOTOGRAPHY. 

CTo thf EclHor.J 
Sir, — Permit me to inform the reads 
excellent work, of the following method 
ing a photographic paper, that gives the ri 
tht'ir proper places. Make a solution of ni 
silver in water, (1 drachm to an ounce 
wssb one side of a sheet of poper with tl 
and let it dry in the mn ,- when perfectly 
it into a solutionof iodideorpota&siam;(4 
to half a pint of water), let this rcmsia 
minute, tliey dry it lightly with bloti 
Lastly, wash with a Bolution of the 
of potass, the side of the paper 
washed with the nitrate solution ; 
blotting paper, and then while moisfj^ 
prcssioti. The parts exposed to the U| 
pale yellow, while the other ports will 
brown. 

These pictures may be fixed, by 
into a solution of bromide of potassium : (1 
to 4 ounces of water), let them remain 
time, then dip them into water, and Isstiy di 
by the fire. j. SATAf 



of nl 

'HI 



L«KDOM,~FrlnI«d by II. Kramcii, 6. Whtl« HarweLnne. Mil* End — Publtalirtl by W. BmrrAiM. II. P« 
EOlohur]{h, J. Mmiia.— Claagnw, D. Hrick and J BAiKn.— Liverpool, J, Pbimp, 




THE 



AGAZINE OF SCIENCE, 

an& ^ct)ool of SLvtS* 



SATURDAY, NOVEMBBH 4. 1641. 



[lid. 




m 



III.— -NO. XXXII. 



350 



MAGAZINE Of SCIENCE. 



VOLTA'8 AIR LAMP. 

Wb b«ve been re|>eatedl]r rtc|nalpd 1« pte s de- 
•cription of V'tiltu'f air lamp, nr, ■» jt mny be other- 
wiM called, electririil iruununroui lii;hl machine; 
we tiike the prrirnt opportunity of doing; *a, the 
more readily at it ia an lootrnuicnt but tittle known, 
and one whicli lone after llie time of its inTeolion 
maintAineil a cunsiderable share of public notice and 
favor, olchoagh now superseded by the hydrogen 
K|(h^ bottle, and it miy bt; truly *sid by the comrooD 
lunfcr matrJir* ; the rrrtain and rapid method of 
obtaining a tight noir, rendi.*nng practically uteleu 
ooonpticAted jihiloaophical light oiarhiiies, hgwever 
iDgenioiu and elegant. Fig. 1 thowi a perspective 
riew of the ioitruraeiit, particularly alluded to. lU 
caie ti made of mahogany, and it has a lOcket in 
front near the bottom to bolda candlvBttcV. A can- 
dle placed in thii euictly reachc« to m hole made 
throofh an ornamental bm&a aculcbeon, higher up 
the nue. The section and position a belter seen iu 
Pig. 2, which It the aide view of the instrument. 
The other figures show the internal structure and 
mode of orlion of the nuichine. Fig. 5 is a longi> 
tudinal aertioi). Fig. 4 a transverse section of the 
upper part ; at A is a quadrant-shaped bottle of 
IfMd, which fits into n corner of the case, seen in 

Eositiun at Fig. 4. This has a pipe below it, marked 
I ; it ia Men letter at Fig. S. The pipe extends also 
nenrly all the way up the bottle. Tlie longitudinal 
aedion shows that the cose is divided into three 
parts— two of which are reprcKentrd much darker 
than the rest; tlie third or middle portion is filled 
with wstrr. The [u'pes C nnd D arc butb oonnertod 
with t\\\A riilddli' diviitinn ; the one pipe, that at C, 
extcnUa from iienr the bottom of K into the open 
apsne abore. The pipe I) is connected with the 
borixontal tube that leads to the jet K, A cock 
crtends sideways as seen in Pig. 4, hoving a pro- 
jacilag handle outitide the iustrumcnt. The lower 
part of the rase contains an elect rophums ; that is, 
two pUtKs — thi^ lower one O of a resinous substance, 
the upper one U of brass or tin. To this last^a 
spring I is attached, though this is not necessary. 
A bird's-eye view of the eleclrophorus plate is seen 
at Pig. 6. From the front edge of H proceeds a 
wire* coniiecled with, or rather resting upon a small 
projecting arm of the cock. Uetween the cock and 
wire is a small glass tube, and the wire is so bent as 
to rest U|>on the point of (he jet, so that the wire 
froiD the clectrophoras touches the jet, eioept when 
the handle of the cock is turned, in which cose a 
amall intcrral between thrro is made ; and when the 
wire of the elcctruphurus is pulled, supposing it to 
be tihargtid, a amall npitrk will pass from one to the 
otlifir. If now hydrogrn gns i« made to pass out at 
the jet, it would be inl1<iincd by thit spark, and 
rnnHrijuriitty the oandle would be lighted, which ia 
thr iilijiT.t drslrcil. To ruriiiith the hydrogen is the 
(4iject uf th<* uppvr part of the instrument. Into 
A are placed some pirties of sine, sulphuric acid, 
and water I thl» of lourse generates hydrogen. The 
gas when foriurd flows down the pipe B, through 
the uiittT, and otvuplea the pipe p, and the upper 
pari of thr wairr veiutrl K, driving the water out 
through (hi* pipi? C When the cork fa turned, the 
gas lluwa mil, Tills instrument, ns was before ob- 
served, Is now Inid aside, being found inconvenient 
un nroount of its sUe. the expense of the hydrogen, 
anil the rapid corrosion and accidental injury occo- 
sionrd tn the tnttrunieiit iLself by the sulphuric ocid 
uieJ in uakiiig the hydrngm. 



THE CALCULATING MACUI] 

Tbkkb an few efforts of the mind* more ^t^nt 
irksome, dry, and monotonoos. than fV" •^■"■^■r 
of making long ealculations. The i- 
ceasing attention to a subject in itself ' 
terrat, when the slightest intmston of UiOagfat 
fanrj destroys the work already done, and cunp 
OB to return our weary way, is enough to addle 4 
•tupify the brain. No wonder, then, tb«r, fW 
times immeronrial, the ingtnaity of man should bi 
been directed to the discovery of some contnva&il 
whereby this we.irifome labor might be lightened < 
abridged. Hence the ioTenUon of calculstiiig il 
itraments and mechanical aids of rsriAus kind 
This long-sought desideratum appeara at Imflhl 
have been obt/iined ; but before we present tu m 
readers some account nf tlie latest attempts 6f d 
kind, we will take m rapid glance at the viirioasfll 
deavoura previously mode to accomplish the md I 
view, and which will place in a more conipicooi 
light the merits of this new invention. 

The instruments hitherto contrived for aidiltil 
or obbrerialiitg culcululiuna may be clossifiej | 
follow : - 

1. Sudi as supersede the mere setting dowBi 
figures, but requires as close on application of tl 
mind a« common arithmetic. To thisdsasbdel 
the calculating boxes uf the Russians and Chiaai 
where the figures are represented by baUs nan 
by wires. Etcn the Romans poctctted an iaiVl 
raentof this kind, railed Abacus, in which the 6gaf 
were indicated by buttons running in groovea. 

2. To another class belong audi instramenti 
arc constructed on the following principle, *U. :■ 
Two long slender rules arc divided into 100 rqn 
parts, those parts being numbered from to 10 
and are thus used : If. for instance, it be desired 
add 17 to 23. the rules must be so pisced that d 
of one shtiU be exactly opposite to 1 7 iu the nt&i 
thru by finding 2.'^ on the ftrst. you wlU have hsU 
it on the second ihn number of -10 at the resoU. I 
on the contrary, you wieh to substract one ntnob 
from anoUier. as 13 from 30, the number 13 oao 
rule must be brought opposite to 30 on the odu 
and under the of the former you will find 17, ll 
remainder. Such eontrivances, being of very H«il 
utility, and partaking more of the character tk to 
than of practical inventions, have loog since sai 
into oblivion. Instruments on this principle sin 
square, and others of a circular form, bars tn 
produced by Perrault, in 1720; Paetins. in 173( 
Peregre, in 1750; Prsbl. in 1789; Gnuoh 
1790; Guble. inl799, Ac. 

3. A third rJasa nf instruments for • 
culstorg comprises the "Virgulu: N<.j 
likewise the other two works of thii^ id ■■iriy 
Scotchman — namely, his ** Molttplic^ttonls i*r09l 
tuorium," sod his "Abacus Arcalis,^* in >•*)* ' 
his footsteps followed Caspar Scott, 

meam, 1731; Lordao, in 179S; Ijf, 
and others. 

4. Equally welt known with ttte forvgoiuf is A 
calculating scale, so much used by the EnfUsli D 
mechanics, which was invented by Michael SJuAlr 
of Ulm. in 1G99. called the ilide rule. 

All the contrivances above eoumernted, anil allxn 
which we pass over in this brief sketch, do nrtslal] 
diminish the labor of arithmetical calciilaUO(ii,aDn 
or less, but they all require the atteotiou to be taf^\ 
and do not completely attain tb« object »vfilt< 
Hcoce the aim of scientific men has been tu iv*'' 




MAGAZINE OF SCIENCE. 



351 



)n sutom«ton, or self-acting instrument for calcu- 
lation, whtch alone raa ilcserre tUt: name of a cal- 
ruUting mftrhine. The! first attempt of this kind 
pru fuiule hy Blnjsc l*u»ral, in 1040. His machine 
perfomirtl addtiion and substruction nin:h«DicaUy ; 
pot it was so difficult to work, and tlic nieclianism 
ID imperfect, that it *raa soon discarJed and for- 
||Otl«fi. & similar destiny attended a cDschiue fur 
laddinif^ and subtracting, invented in EngUnd by 
Ssmitcl MnrrUnd. in 1673. His other mathema* 
inatmiDent is nothing more than an adaptation 
lier's scale to circles for multiplication aud 
The defects and insutficiency of thetie 
reationH of PhkciI and MorcUnd gvfc rise to 
|UCot endeavours to improve them. Lcptne 
i, and HiUorin de Boistissondean in 171^0, 
more successful tluui their predecefwora ; 
Gerstcn's invention, submitted to Che Royal 
of London in 1730, afford any greater 
ion. 
luly, in 1709, Folenias tried his skill on a 
le of this kind, 'hot produced only a coarse 
lUy abortion, incumbered with weit^ht^, that. 
Uifcnor to those which had preceded it. In 
«asea the aim of the inventors was only to 
■ddlCion and subtraction. Leibnitz sought 
the operations of on arithmetical calcu- 
' to multiplication and diruion. The plan of 
chine wus submitted to the Royal Society of 
in ]ri73, and met the approbation of the 
A nmilar honor attended it a short time 
rarda from the Academy of Sciences at Paris. 
despite the afiprobation of those cclebralr!d 
bodies, the plan which looked so promising 
proved impracticable in execution. Leib- 
ibor«d hard during liis whole life to bring his 
to perfection, expended vast suma upon It, 
it effected nothing. Death carried him off, 
work reroatned unfinished and forguticn. 
!7 Leupold promised to publish to the world 
m of a iii4cbine thnt should perform addition. 
!tion» and muliiplicjtlon ; he died, leaving 
bim only a few fragmi^nts of his plan. After 
it seems that no further attempts were made 
long period, until, in the year 17'.t9, a miuister 
■mberg, named Hahn, came forward with a 
f.aachiue, which, however, attracted no atten- 
as it was found to commit serious errors in 
ic : its iuternal atruL^ure remains unknown, 
•lao UiAt of a faulty instrument presented In 
imj of Sciences in Gbttingen, by Mailer, 

machine constructed by Mr. Tliomaa Colmcr 
^ was a retrograde step in this branch of 

{the year 1821 Mr. Babba^c, of London, under- 

'to eooatnict a machine fur Government, which 

by mei-honical means, form tables of pro- 

m for tlie use of aarveyera. A portion of 

machine, forming a prot;ression up to 6ve 

I, wai complete — 17,0Ul)/. had been eipended 

. already, and to perfect the entire work would 

Jwve required twice as much more ; consequenlty, 

13, the project was abandoned, and it ia not 

lie that the costly machine will be brought to 

stat«. 

fragment or member alluded to may be seen 

inventor's. Mr. Babbage ia at present occa- 

iib the plan of a machine which ia to perform 

irally all the operations of algebra. Already 

30 plans extant; every friend of science 

heartily wish that the inventor niuy be more 



K 



anccessfal with his new project tli&n lie was with 
the previous one. We come now to speak of the 
recent aurcesKful attempt before alluded to. For 
the last two years Dr. Roth, of Paris, has been en- 
ga^ed in the construction of arithmetical machinea, 
and the success that has attended his efforts hitherto 
proves he has accomplished his scheme for perform- 
ing automatically ell the operations of arithmfltic, 
^om simple addition, aubiraction, mnlti plication, 
and division, to vulgar and decimal fractious, invc 
lation and evolution, arithmetical and geometricaV 
progression, and the conslruclion of lugarithms, 
with ten places of decimals. The machine in it« 
present state works addition, subtraction, multipli- 
cation, and both kinds of progression, quite me- 
chanically. In division alone the attention b re- 
quired to avoid passing over the cipher. The 
nrithmi'tical progressinn ia of vast importance, as it 
operates from one farthing to miUiona of pounds 
sterling ; and when we consider the variety and 
utility of the fanctiona performed by a small instni- 
Dicnt, not more than a foot wide, and its compara- 
tively insit^nificant price, we cannot but congratulate 
the inveotnr on hia decided success in the results 
hitherto obtained, and express our cordial wishea 
that he may meet with every encouragement to 
persevere in hia highly interesting aud important 
labors. 

Mr. Wertheimber, the proprietor and patentee of 
thia invention, hns two deacriptiooa of tliese ma- 
chinea — a larger one which performa sums in ad- 
dition, subtraction, multiplication, and division;'^ 
and a smaller, which performs addition and aub* 
traction only. These machines have been sab- 
milted to the inspection of several gentlemen emi- 
nent for their acientifio attainments, all of whon* 
particularly Mr. Babbage, have exjiressed the most 
unqualified admiration at their unparalleled inge- 
nuity of coiiscmction. — T^me*. 



THE PANAUY FERMENTATION. 
Tbb tlieory of the fermentation of dough and the 
making of bread is involved in considerable obscurity. 
The following comprises almost the whole of wlMt 
ia known of it. 

The fermentation which takes place in dough waa 
once considered peculiar to bread, and bcnoe waa 
nanifd the /canary fermentation. The chief ground 
of this opinion wus, tliat if dough in this stale be 
distilled, it does not afford alcohol ; altliough it 
might have been expected to do so, if the fermenta- 
tion which it had undergone were the vinous. Bat 
thia view of the subject was found to be incorrect. 
by its being ssrrrtnined that infusion of molt, mixed 
with yeast, although it certainty undergoes the 
vioou4 fermenLiiioit. gives no evidence of its having 
done so by the test of distUlation ; for if it be dis- 
tilled during the beginning of the process, it will 
not afford alcohol any more than the dough. Be- 
side thia negative proof, we have one of a positive 
nature. It has licea found by experiment that 
dough, when KufRciently fermented, actnally doea 
afford alcuhol. It is, therefore, manifest that there 
in no specific difftrcncc between the two exhibitions 
of fermentation ; one is the beginning, the other the 
sequel : in the one carbonic acid only ia produced ; 
in the other alcohol also is generated. 

According to the anatysis of wheatoo flour by 
Vogel, one hundred piirts contain live of a peculiar 
sugar. We may therefore suppose that the action uf 
the yeast, made use of in the process of fermenting' 



252 



MAGAZINE OF SCIENCE. 



th« dough, is exerted on this lugar ; thAt it is 
decompOKd ; that carbonic acid is formed, and lit 
length alcohol. The imall quuiUty of sugar pre- 
sent in the floor accounti! for the small quantity of 
riirbonic arid evolved in the doagh. Bat there is 
unque*tioD&bly some other chemical change pro- 
daced ; for the bread when fintabed oootains neither 
of its two chit-r constituents, the gluten sod starch. 
These two principles ore known to exert a chemical 
action on each other, and to produce saccharine 
matter. But during the fermentation and baking 
of dongh vfc do not find that sugar is formed : we 
muHt therefore suppose that both the gluten and 
starch, by their mutual action, are converted into 
some intermediate stale of existence. When sagar 
is formed by the action of these two principles on 
carh other, it is the starch thst suffers the conver- 
sion ; the gluten is bat little affected. But during 
the changtT which takes place in the fermentation of 
dough, the gluten is as much acted on as the starch, 
and hence its change is as complete. Perhaps the 
difTcn-'uce in the nature of the change is attributable 
to the very clevntcil teoiperalure at which the chc- 
micAl action takes ploct: in the oven. 

CoDceming these changes, the opinion of M. Da* 
portal is, that the ytatt, after having converted the 
sugar of the flour into carbonic acid and alcohol, 
changes the latter into acetic add ; that, at the sntne 
time, the gluten and the albnmen are in part de- 
composed, acetic acid is again product, some am- 
monia, and more carbonic acid ; nudthat, the starch 
KMffin; with the undecomposed gluten, there results 
a compound, the further altcratiun of which is pre- 
vented by the action of 6rc. which combines these 
principles still more intimately. This theory M. 
Duportol conceives to be supported by the following 
facta: — 

" istf Those fsrinse which are deprived of the 
fermenting principle, or those which scarcely con- 
tain any uf it, always aflbrd heavy bread, although 
the aaccharine principle forms a part of them ; for 
this substance not being a fermentable priociple, it 
cannot ferment of itself, although it does so by 
means of a ferment. Thus it is customary to add 
to the douglt a leaveu, taken from bread already 
fermented, or the yeast of beer. 

** 2d, Dough is always acid, notwithstanding that 
the volatile alkali formed in the operation neutralises 
one part of tlio acetic acid, as is proved by the am- 
nioniacal odour of dough treated by potash. Bread 
itself always contains a little of thia add, which 
heightens the flavor of it. 

" 3d, The starch, the undecomposed gluten, and 
the other materials of the dough, arc so intimately 
tiaited by the bakini^, that it is no lunger possible 
to separate them. We can discover, by the distiUa- 
tioo of bread, an animal matter, for it forms acetate 
of ammonia ; but a less quantity of this is obtained 
from it than from farina, according to the observa- 
tions of M. Vauquelin. 

'* 4lh, The formation of carbonic acid is rendered 
evident by the volume which the dough acquires^ 
and by the numerous cavities which are to be seen 
in it. This gas escaping while the bread is baking, 
dilates the moss still more, which causes the air to 
lodge in these cavities — an important circumstance; 
whmce results the remarkable whiteness of bread 
full of little holes, so light, delicate, and sapid, in 
compariiuu wttJi the bread destitute of them, which 
is heavy, compact, and of a disagreeable taste. 

" It ill, therefore, more particularly ihe ferment 
which has the most active ihuc in producing poni- 



fioation. Aii<led to dough in small quantity, 
operation is slow and tncomplete ; in too \:\tfp i 
jwrtion, the fermentation goes on so rs) ' 
becomes necessary to check it. In U.'" j 

Mt Chaptal proposes to knead some catbuuouuf 
potash with the dough, which will ncutroliae the 
eiceas of acetic acid. Oar good housewives coatnt 
themselves with uncovering the dough, dividing kE, 
and exposing it to the air, in order to diniimsh tk« 
temperature of the fermenting mass; and this a^ 
nagement sometimes succeeds.*' 

The coarser kinds of sugar, along vrith the pin 
saccharine principle, contain a ferment propa to 
themselves. The sugar produced by the action af 
sulphuric acid on starch is also associated with hi 
proper ferment. There can be Little doubt tbit Uie 
saccharine substance obtained by the matuol actum 
of gluten and starch contains a peculiar fe 
Hence, all these kinds of sugar would spon 
enter into the vinous fermentation. A 
we find thatwbeaten dough spontaneonslyfi 
and we most attribute the change to the p 
of a Dstural yeast belonging to the pccoiiw 
which whcaten flour has been proved to 
The vinous fermentation, when once it baa 
menced in dough, will proceed into the 
stage, and from that it wiU go on to the pal 
We can, therefore, be at no lost to understairf! 
nature of leaven. We comprehend why a m 
of flour and water, after some time becomes 1 
in all parts with air bubbles; why it tsms 
and finally fetid. And we can perctrive why a 
of this leaven, in a statu of nctive deoon< 
such Ba has been described, will induce tha 
sort of change, almost immediately, in a 
of dongh, which, without such addition, a 
have undergone the same subversion of ita 
but after a greater Ispie of time. 

Although the sugar oootaioed in corn is 
with a nstural ferment, and although this 
foiiud capable of czcitiDg the vittuus fennen 
dough, it is not adequate to produce a proper 
fermentation in watery infusions of the gralii« 
the contrary, such infusions pass rapidly inl 
acetous stage. There is evidence, however, 
previous existence of a vinous fermentation, 
tory, it ia true, bat still sufficient to generate 
in a quantity thst may be appreciated by i 
tion : but in the com of dough ttic results arc a 
diflVrent ; the small quantity %( water pi 
obstruction to chemical action occasioned 
stiflness of the paste, and, perhaps, other 
operate in such a way as to protect the fcnneai 
from theH])prouchea of acetitication, and to 
the vinous stage until the operation of the oven 
an end to it. 



MANAGEMENT OF GREEN-HOUSS 

PLANTS, 
Tbk cultivation of exotic planta, whetlMr psnvd 
witli the view of producing fruits or flowers, ntfi 
be admitted to bold a conspicooiu rank in boftt* 
cultural science. A taste for the enjoyneati d 
this pursuit existed at a very early prnod, ifli • 
has kept poce with the more refined and I'rJiJttl 
arts wherever these bsve floorished. Ti 
of the ancients sufficiently prove, thn\, 
nations of antiquity, a very stroni; 
i.sted for the cultivation of cjtotic i: 
has continued progressively to iuvf "j- " — 
present time. Grocn-houscs and stovfs werv if^ 



m^ 



MAGAZINE OK SCIENCE. 



S53 



this country during the screnteenth cen- 

durini; the early part of the eigbteeeocb 

cnltivniitiu of tfxotic planU wu carried 

t *piril, upwards of live thonsand bang 

from forrign countries, beiidei the re* 

ay neglected species. The Utter part 

teenlh, aiid the begioning of the nine- 

tury, however, has been the great bo- 

for which this country will ercr be con- 

Thc discovery of Australia, the eiten- 

e British power in India and both the 

aided by the patronage of the most 

locracy in the world, have brought a 

o of power to besr on botanical discovery, 

beeo Attended with the moflt hippy re* 

t only have botanical and borticultuml 

D established in atl our principal cities, 

ones are mkintaine«l with princely tibcr- 

y of oar nobility and gentry. Indeed 

for uotic botany snd florticulture seews 

among all classes ; and the number of 

emplujed in diiTerent parts of tlie world 

that the taste is rapidly increasing. 

' now speak of the green-bouse itself, for 

depends upon adupting the structure as 

temj>erature of it to the plants to be 

it. The house sutficicnt for small 

course will Dut accommodate those of 

and it is equally true, that a house 

accommodating the latter is unfavorable 

plants, which uniformly require being 

cIo«e to the light as circumstances will 

gain, the situation which is best calcu- 

to orangery, or a camellia -house, which 

• very moderate supply of air and light, 

means do for a heathery or ^ranium- 

which air and light cannot be supplied 

tly. Indeed, so various are the detide- 

outs requiring artificial cultiration, that 

yodiise every amateur, unless bis means 

pie as timse of the proprietors of Sion 

Alton Towers, to con5ne his attention to 

most nearly alike in their habits, in> 

Dgregating a confusion of plants of dJs- 

U, and requiring difTeront temperatures, 

building. Their object should be to form 

selections, instead of ■ numerous coUeo- 

|| not to socrilice real excellence to an idle 

Vr variety. Indeed, no one should attempt 

cultivation of plants as a general col- 

he has means and space to afford 

dings for those families which demand 

singular degrees of light, teropei-ature, 

for otherwise, by continually varying the 

these particulsrs, to force this plant or 

other, be will injure, if he docs not 

a whole. Our continental neighboun 

h more prudence in this respect than we 

rto done ; and even our gurden florist 

good example by confining himself to a 

his tulip bed, his auricula stage, or 

on stand, for instance, preferring excel- 

departmeot to mediocrity in all. Sub- 

■ fenr operations demanding the notice of 
r. 

irouDV naEEN-aousK plants. 

of propagating these plants is by cut- 

■ few ftorts are sometimes layered, grafted, 
and a number are raised from seeds. 
from cuttings should be commenced 

4(id of January ; cut nnd drr^s them neatly 
krp pcnLnifo. taking otf all the leaves as 



cloec to the shoot as possible, except a fen at tht 
top, to be left for the free respiration of the cat- 
ting. This shonld be particularly attended to in 
making cuttings for evergreens, whether tender or 
hardy. Ijct them be cat off at the bottom, with a 
clean, horizontal cut at a joint or bud. and placetl 
immediately in their proper pots, which ic is very 
necessary to have properly prepared, half Ailed with 
monld or compost, and afterwards filled with good 
loam or asm), and well dramcd. Cover them with 
proper glasses, so as to exclude the air; then plunge 
them in a back-pit or in a bot-bed frame, made for 
the purpose, shading them from the powerful mys 
of the sun, until tbcy are sufficiently strong. May 
and June is the niOAt proper time tu propsgiite siit^ 
as myrtles, oranges, ractrosideros, baukaias, &c. 
If begun in June, which is early cnongfai they must 
be placed in a cool, shady situation ; an exhausted 
hot-bed, with a frame and good light« on it. will 
answer very well ; in July and August there will bo 
many of the earlier cuttings growing ; they should 
have their glosses taken off, as before directed, and 
be set for a few days in a more exposed situation, 
to harden them by degrees, in which they must be 
shaded from the mid-day tan, but freely exposed to 
the air at night. Water should be freely adminta* 
tered, except in fo^y damp weather, and thai 
sparingly. 

OBKAXIVMB. 

The ordinary mode of propagating each species 
and variety of the geranium is by cuttings; but 
almost all the sorts produce ripe seeds tu this coun- 
try, by which they mny be multiplied, and new 
varieties produced. The seed, if ripe before Mid* 
summer, may be sown as soon as gathered, in pots 
of light rich earth, and placed in a grntle hot-bedp 
and shaded. The plants will soon come up, and 
when they show two proper leaves may be trans- 
planted singly into pots, kept under a cold frame. 
Several of them will flower in the following spring 
and sttmmer. The shrubby or anffruticose species 
of this family grow more readily by cattiogs, wliich 
may be taken off at a joint where the wood is be- 
ginning to ripen, and laid In the shade for an hour 
or two till the wound heals, and then planted in 
aandy loam, and placed in b gentle heat. The hardier 
sorts may be planted in the open air, or in any 
shaded situntion, without being covered with a glass. 
From the latter end of Maroh to the end of July* 
cuttings of all the common kinds rosy be put in 
with success. Make a moderate hot-hcd, surfaced 
with some old tan, and when of a proper tempera- 
ture, let the cuttings be made and put in some rich 
loam ; plunge tlie pots to the rim in the beds, and 
shade them for a day or two, but no longer ; water 
them occasionally, and pot them off in rlue time i 
by which means they will be stout plants by the end 
of the autumn. Geraniums ret^uire a rich tight soil; 
they grow well in equal parts of sandy loam and 
well-rotted dung; or they will grow in leaf-mould 
and a little sand, without any thing else. As most 
species are rapid growers, the pots rnioire examin- 
ing in spring and automn, and the roots and top 
reduced, or the plant shifted into a larger pot. The 
shrubby sorts should ha kept low and biuihy by 
pruning : for when allowed to grow tall and strag- 
gling, they are very unsightly, and do not flower 
well. The hardier sorts may be placed in the open 
air from May to September, and in warm situatiani 
they may be planted in the borders of the flower 
gHrdrn or shrubbery : tliese have a good effect till 
attacked by frost, when they may be protected by 



i 



S54 



MAGAZINE OF SCIENCE. 



BbundiiQDe of litter and mats, or they roaj be re- 
moved in single pots, tiad placed in ■ dry part of 
the greenhouse till the fulloNing apriiig. 

MISCKLLANBOUia CHOtCK PLOWBRS. 

TAeFuchida. — This elegant and oruamentalshrubi 
though requiring the green-house in the winter, will 
grow vigorously, and flower freely in the open air, 
duriu); luninier. The moat beautiful are coccinea* 
rilis, TirgaCa, conica, microphylla, and some 
i lately raised, eucb ai globosa, Tbompsonii 
Robertnii. All are propagated with the greatest 
ease by cuttings ; and they may either be planted 
out of a small size, in spring, or trained in pots, 
for two or three years, till they form the tree<ltke 
shrubs, of five or six feet in height, when they may 
tw turned out at the beginning of every summer and 
taken up every winter. Some of the more hardy 
will stand over the winter, dying down to the ground, 
and filiooting up vignrotisly the fallowing spring. 

The Cameiiiita ceieatis is a perennial, wtiich will 
flower the first year, if treated like a tender annual; 
while if its 6eshy roots are preserved through the 
winter in dry sand, <!xcluded from the fruit, (bey 
may be planted out in the following spring, after 
being brought forward a short time in a hot-bed. 
Sow the seeds early in spring, on a moilerate hot- 
bed, and bring the plantJt forward in separate pots, 
turning them out in the open garden in the begin- 
ning of May, or sow in the open ground in the be- 
ginning of March. Light rich soil is preferable. 

The Vtrbenat are beautiful half hardy {lerenntals, 
which form brilliant omamenlsto thetlower-gnrden 
during summer. They arc propagated by cuttings 
kept through the winter, in small pots, and turned 
out when all danger from frost U over. Light rich 
soil suiLs them best. 

BaitamH. — The varieties of these tender annuals 
are infinite ; the seeds from one plant will hardly 
produce two alike. They are raised almost always 
from seeiU, but they may be propagated by cuttings. 
The seed should not be less than three or four, or 
even nine years old, gardeuers having experienced 
that new seed seldom produces double flowers. The 
t)est soil is a rich loam, rather lighter than that used 
for melons. Sow between the Ist of March and the 
let of May, in pots, very thin ; place them in a hot 
bed and as near the glus as possible. When the 
plauts are five inches high, transplant them into 
No. 4B pots, one plant in the centre of each pot. 
As the roots fill the pots, move them into larger 
ones, and repeat this three or four times, keeping 
the plants all the time In a hot-bed and near the 
glass, or in a pit. Balsams, so treated, will rise 
four feet high and fifteen feet in circumference, with 
strong thick stems, richly covered with large double 
flowers. 

The Amarenthvt THcohr, Cclosia cristata or 
Coxcomb, Gomphrena globosa or Globe amaranth, 
Mesembryantheunm crystallinnm or ire plant, 
Solonam melongena or egg plant, and most other 
tender annuals will attain to correspondiog lozu- 
riance if similarly treated. 

The Hydrangea. — A succtssion of young plants 
may he raised each year by taking, in the early part 
of July, young shoots with three or four joints, cut- 
ting them off close to the bottom joint. These are 
planted in rich earth, in a warm border, and covered 
with a hand-glass. Shade them during the middle uf 
the day, and water them gently every other evening, 
keeping the glaM close over them. The cuttings 
wUl be well watered in August, and may be potted 
iu September, and placed under a frame, keeping 



them shaded and watered as before. 6y the end ni 
October take them into the green-house for thv 
vrinter, and water them once a week or a furtnijibt, 
as they may require. By the end of May tbey may 
be turned out in the open borders, into a rich bof 
of earth, and there remain till .September, wban 
they must be taken up ond potted, and plaMd li 
the green-house, as in the preceding winter. 

ChtytanihemMmM. — No plant is more eaiOy aU 
tivRted than this. The root may b« divided, and 
suckers taken off, or cuttings taken in, tlie begio- 
ning of April, from the top shoota of last yesr*! 
planta. They are planted in pots, called 
in mould msde up of equal parts — loam 
bog-mould. Take the cuttings three inchea 
and cut them smoothly across at a joint ; one 
in each pot, and the pots set in ■ frame, on a 
bottom heat ; in three weeks or a month 
well rooted, and then hardened in a cold 
the beginning of June, when they are ahifVed 
48 sixed pots, and placed in an open airy sit 
Here they are watered with liquid manure, bi 
soap-suds have been mixed. About ttits ti 
tops of the planta arc nipped off, to make 
bushy. In August shift into 32 stxe pots, 
strong loam with about one-third of rotten 
and tie the plaoU to slicks. The old plants. If 
out of the old mould, and rvpotted in 49 sii 
afterwards 32'a, and En August 16's, will form 
showy plants. 

Heart' i-ea*e. — Nothing can be more easy I^ 
the propagation of these plants, either by seeds of 
cuttings, but by the tatter motle with the grcsM 
ease in common garden soil. Seeds may be fom 
early in spring, under hand-glasses or in a ooU 
frame, and the plants may be first jiricked out onder 
I glaas, and afterwards transplanted into beds in ikl 
open garden, or put into pots. The sitoaUoaboA 
adapted for //ffruf'rs should be open totbetutfif 
west. The surface should be low, so as to nidi 
moisture, and be cooL The soil a aandy loam Ugl^ 
mantired. 



THE ORGAN OF TASTE. 

nr M. DONOVAN, K8II. 

TiiR subject of this article, curious and intend- 
ing as it would become if industriously pt 
has scarcely occupied the attention of tb 
have inquired into the mysteries of the 
senses. The investigiition of the properties 
organ of taste is attended with peculiar 
because this tense is more variable than 
amongst mankind, and is not permBOCal 
same person. 

The nature of taste has ne^'er been 
beyond the simple statement of the fact, 
an impression made chiefly on the ncrr 
tongue and the mucous membrane of the] 

lilts impression may be made by the < 
certain solids, liquids, and elastic fluids. 
oxide gas received into the mouth tastes 
carbonic acid is acerb ; hydrogen has a 
cannot be expressed : it is perceived on acid 
which have been that Instant cut with an iroa 1 
ammoniacal gas has an iniupportably pungent 
and chlorine is aiitringent. The taste of solids i 
liquids need scarcely be alluded to. 

Some solids that have no taste in their orfia^f 
state acquire it in a singular way : thisi OffM 
metals have no taste nnleu they bare been reefl^f 
rubbed : others, that arc perfectly tttatdMS wkff 



j^^y^gmi 



MAGAZINE OF SCIENCE. 



255 



||}uire one wken ihey irc brought in con* 
ich other. 

not an attribute or pODcIerable matter 
I if a Btream of electricity be directed on 
frum a {lointed wire attached to the con- 
IB electric machine, a distinct flavor is 
SuiBctimea tastes are perceived without 
flon of anr rxtemal exciting cause to the 
It impressions of sourness, bittemeis, 
I, are common rcaulls of disease. 
in oaed aa fnod have always a certain 
bute, and, wilhin limits, the more de- 
ktethe morf> agreeable the aliment; this 
piled tapidity. The absence of it^ or 
b »o great a defect thnt it renders a sub- 
t for food : the presence of such in the 
Rpable of exciting nausea, and even the 
bf the stomath. To some persons, chew> 
iirk or a bit of white paper is a sufficient 
fater, of the same temperature as the 
^ in a similur way ; but coht water ac- 
p from the air oontAined io it, and its 

It mreely ever almple tmpreflsions, bnt 
Bit of two or more acting at the same 
I resulting effect is often very different 
llementory tastes, and not a mixture of 
t thin happens even when chemicnl com> 
• not taken place. If wild carrot-seed 
td on ale, the Latter acquires the taste of 
^ although neither the ale nor the seed 
It flavor of the kind : ond the common 
& ton ps precisely as if shU had been added. 
luioui fact that the elementary imprrs- 
I produce a compound taste, need not 
Ipplied to the mouth at the same time, 
A applied at well la saccession. The 
i ahrub called ana&ah, which is common 
f, u nearly destitute of all flavor; if 
nevertheleH so affects the nenres serving 
D of taate, that all acids token afterwards 
luth appear iweel : vinegar will be mis- 
irret wtue, and a lime for a sweet orange. 
tct is, no doubt, produced by a certain 

left on the nerves of toate, after the 
Jthdrawn, and of which the person who 
ItrUt is not cooficious. It would appe&r 
prnt affected become torpid to that im- 
bd remain so until they are excited to 
ke appUcatioa of some other ; and then 
I one revives. A person whu eats a raw 
After a while, cease to perceive 'tis flavor 
ih ; but in an hour or two he may renew 
nring a cap of tea ; or, if the atmosphere 
by a draught of very cold water. The 
loQed onion is best renewed by a amoll 

brandy, diluted with much water. If 
jftf pepper be diffused over the mouth, the 
k of it will at length subside ; but let the 
IBT uke Into bis mouth a little brandy, 
^t and he will perceive the heat of the 
IreCom, and the brandy will appear to 
latrooger than it really is. Those who 
tods on ardent spirits are quite aware of 
ky of aromatic substances : they first let 
treoglh uf the spirit with a little water, 
bring it up again by iofujiug CaycDDc 
icardamoui seeds; the stimulus uf the 

the palate disposes it to perceive the 
t the spirit, even in a higher degree than 
tfaerwise have done : aud that this is a 
AIqa of Uie nerves of the organ is ploin, 



from the fact that the tasto of the pepper U not 
perceived, while that of the spirit is; the latter 
being so much greater io quantity. The taite of 
even the strongeat brandy will be enhanced if a 
single cardamon aeed had been previoualy chewed. 
The contrary proctiM has been sometimes renorted 
to ; although I believe it ia almost noiversally di>> 
continued. When wine is new, the fiery taste of 
its brandy predominates on the palate : to disguise 
this it was not unusual to add to the wine a small 
portion of sugar of lead (a poison,} which, hy its 
sedative effect on the organ of taste, caused the 
pungency of the br«ndy to be less perceptible. This 
was not tlie only case in which sugar of lead was used. 

To predispose the organ of taste to certain im- 
preuions is a device which has been long practised, 
— perhaps always. It Is an old method of creating 
a relish for wine to preface the ntploits of the 
evening by eating a few morsels of meat, broiled 
with a large jtroportion of pepper and mustanl : the 
stimulus on the palate not only continued for some 
lime, bat was perhaps reproduced after it would 
naturally have subsided ; and the organ of t*iste, 
thus prepared, perceived a more exalted flavor in 
the wine than would otherwise have belonged to it, 
the effect being quite independent of thirst. 

The bnming sensaUoa produced on the mouth 
by aromatic substances may be reproduced by 
liquids liaving a much higher or a mnch lower leni- 
pcmture than the month itself. Thus when the heat 
of pepper has subsided on the palate, it may be re- 
newed, in a slight degree, by a draught of very cold 
water ; and when the peculiar burning occasioned 
by chewing peppermint leaves has diaappeared, a 
quantity of hot water taken into the mouth will 
restore it- 

Thc substances which produce and reproduce a 
stimulus on the organ of taste need not always be 
acrid or heating : some that are remarkabLs for 
mildness of flavor are equally efficadous. Thus 
the root of liquorice, when long chewed, leaves an 
impression of feeble sweetness, which very gradually 
subsides : as soon as it is no longer perceptible let 
the person take a draught of buttermilk, and in- 
stantly the sweetness will return. The extract of 
liquorice, sold under the name of Spanish juice, 
possesses the some property with regard to porter, 
in a llight degree it is true, but suilicieatly to 
modify the taate of it In a manner that is agreeable to 
many : I have accordingly known persons who pre- 
pared their palate for a relish of this kind by chew- 
ing some of this extract previously to taking a 
draught of porter. On a somewhat similar prin- 
ciple many people approve of ale after a fruit pie, 
when weak acidulous wines, as bock, would be dis- 
agreeable ; for although a sweet and sour form a 
good combination, the latter does not bear to follow 
the former. 

When stimuli have been applied to the organ of 
taste, and the perception of flavors has thus been 
rendered more than ordinarily acute, it will be found 
that weak and vapid hqnors will appear to still 
greater disadvantage. Of this a person need have 
no better proof than taking a draught of weak and 
acescent beer after eating a highly seoauoed salad, 
it will bo rendered far more disagreeahle ; whereas 
ale, in high order from the bottle, and foaming with 
carbonic acid, will be rendered more pungent and 
penetrating than ever. It is on the some principle 
that coffee should never precede tea, but ought to 
follow it ; and then bolit beverages will produce 
their proper effect : this ordcff however, is rarely 



256 



MAGAZINE OF SCIENCE. 



obterved, became cotTee is an exciter of Lbint ; tlie 
nerves which supply the organ uf taste ars over- 
powered by the ruogh aHtringent bittemo-ti of the 
cotfee, and are then not in a condition to peroeive 
the delicate flavor of iea — (or delicacy ia ita chief 
perfcetiou. Tliose phfiirtans appear to be right 
who direct that lieltcate pereons should create a 
a rcliib for a tea breakfsit by the preparative of a 
stico of toasted bacon ; few thing* are more sac* 
oenfol in rendering tea enticing. 
CTff fr** conttHutiLj 

POLARIZATION THE CAUSE OF THE 
RAINBOW. 

SiiL< — I should feet much obliged by your inacrting 
(he following in your Magazine. 

When n poHion of a rainbow ii viewed through a 
tourmaliuc, and the toormallQe la turned round, till 
the direction in which it polarizes light coincidea 
with the chord of the arc viewed, that portion en- 
tirely diiappears, in consequence, (I think.) of the 
colored mys bring composed of poUrizi^d tight. No 
work with which I have met makes the slightest 
mention of this phenomenon, which I think would 
modify the explanation given of the formation of 
the rainboWi wbereiu polarixation is not hinted at. 

J. WILl-SMRR. 

CURIOUS EXPERIMENT. 

r To the Editor J 
Sin. — An old subscriber to your truly original and 
talented work, would feel much obliged if the editor, 
or any one of faia iiunmrous acientiftc ajid talented 
correspondents, would favor him, and a numerous 
circle of friends, with the rational and true chemical 
explanation of the following surpriaing experiments, 
given in "Ferguson's Lectures on Select Subjecta,** 
page I rfl, article, Pneumatics : — ' * Air that will lake 
fire at the Hume of a candle may be produced 
time: — Having exhausted a receiver of the air-pump, 
let the air run into it through tlie llamc of the oil uf 
turpentine; then remove the cover of the receiver, 
Bnd holding a candle to that air, it will take fire 
and bum quicker or slower according to the density 
of the oleaginous vapour." 

Aa PerguBOD wrote and flourished before the 
new chemical nomenclature had been regularly 
Mtiblished, it could not be expected that he would 
give any rationule of the phenomenon which, indeed, 
be no more than barely records, bat which I con- 
fld«r of so remarkable a nature ai to deserve the 
cleareat explanation which the most improved mo- 
dem science can give to it. I have, however, in 
vain looked through modem works on chemistry 
withoDl being able to find anything to throw a light 
upon it, or anything analogous thereto. 

INDICATDA. 

[We would ask if oar triend has tried and found 
the exiMsriment to succeed ; if not a fact, it is vain 
arguing upon the subject ; if true, it may. perhaps. 
be accounted for, by the fact that bodies of a fatty 
nature previous to ignition give nut carburetted 
hydrogen. If this be collected, and in contact with 
oxygen tt will iuflame. Our doubt is, firstly, 
whether there will be a sufficiency of hydrogen thua 
collected to produce the effect; and, secondly, if 
there be enough, whether explosion will not ensue. 

— KO.] 



MEDICAL RECEIPTS. &c. 

Spitibmrjf'a An/iMCorbufie Drop*. — A 
compoied of 2 ounces of bichloride of m 
dram each of prepared sesqui-BulphuTet of an 
and red sanders-wood, rasped, 2 oonoes 
oraoge-peel and gentian root, ( pint rich of 
fied spirit rtnd of distilled water; macrntd 
filter, so OS to form a tincture. Dr. lltncMl 
found no mercury in a spccimea purchased of tfct 
proprietor. 

^rMce Brer is made by adding 4 drama of coMiel 
of spruce to 10 gallons of water, aod 4 poudft 
■agar for white, and treacle for brown epnioo 
alKi yeast in the same way aa for gii^er-bMiv 
bottle up. 

Sprvce Beer Powder*. — Take 5 scruples of vUlt 
sugar, 24 greiiu of seaqui-carbnnate of soda, nl 
10 grains of CMeoce of spruce, for the blue p*|«« 
and ^ dram of tartaric, or, what ia better, atrit 
acid, for the white paper. Dissolve in «cpftnli 
glasses of water ; mix, and drink immediately. 

Squire'* Ktixir.—^K nostrum composed of S9 
drama of opium. 1 ooDce of camphor. 1 drara 
of carbonate of potass and oochincal, 2 ou 
burnt sugar, 1 pint of tincture of Bnakerpot. 
Ions of spirit of anise, and 8 ooaoef of snip 
tin. Other formulc are given, oontaining 
liquorice, &c., but opium is the basis. 

Siarkty'M Soap. — A oostrom prepared by trit»» 
rating for a long time, and carefully, carbontt^ al 
potass with oil of turpentine, with the addiltoedf 
a small quantity of water. 

S4eert*s Opodeldoc— \ nostrum eoinT'""*'^ «'f 
ounce of Ca&tile soap, 8 ounces of recti 
3^ drama of oil of rosemary. 1 dram 
origanum, and 4 drams of liquor of ammonia. 

Slephen*'* Remedy for the Sione, was s f*^ 
made with lime procured froitf cgg-shella, ani niiB- 
shells caldaed. Along with this soap, whirh *• 
given in form of pills, a diuretic and lajtolire 
lion was given, prepared with diamoadle, 
parsley, aod burdock, witli some AUcant 
When pain was produced an opiate waa giv^a, Bn 
when the deooetion purged, it was ixitermiitHl. 

5/erry*f Platitr. — A nostrum rcry popnltf 
London, and composed of the common 
plaster of the Pharmacopoeia, or smm on isc 
solved in vinegar, and spread on brown paper. 

Storey'* Worm Cake*, — A oostrom coopessdof 
1 scruple of jalap, 1 dram of ginger, 2 scmp^ 9 
sugdr, 1 onnco of cinnebar, and aa much of Ijnf 
as is sufhcient to make tbem into cakes. 

Stoughton"* Elixir, — A nostrum composed cf I 
compound tincture of geottjui made with 3) pofBJl 
of gentian rout, 1 pound of Virgiidnn sn^tfM^ 
1^ pound of dried orsoge-pceJ, 4 oimee« y ^>i •"•■>* 
aromaticos, and 6 gaUoo* eacdi of rvc 
and water. Cardamoms are sometimw ni' ' 

Struve'* Lotion for I looping -Covyh. — A xuatJVA 
composed of 1 dram of pota«sio-tartr«tc of to^ 
mony dissolved in 2 drams of distilled w»icr< > 
wbi(^ add 1 dram of tincture of canthaHdes. \tk 
curious to see thii coming again into fa^ioe.twff 
the auspices of tbe bte venerable Dr. Jenaer, ui* 
the form of antimonial ointment. 

Tnnic Wine (French),— k nostrum whkk o"; 
ginalcd with the editor of the •' Medical Adfur,' 
con&istiog chiefly of tincture of aloes and flth' 
purgative tinctares. 



LoirDO«.~Print«d by D. PuNCti, 6, White Hone Liiim, MlW End.— Puhllih«cl by W. BamAtN, 11. PiUviBMlif A**- 
CtMBtBUnlcaUoiu. (wtiicli or* aiuw<r«d Monthly,) tu l»e addrcsird to Ibe Editor, al 87, Coitage Cf«vf . »l>* CW w* 



THE 



AGAZINE OF SCIENCE, 



^nb ^rfiool of ^vtg. 




DR. URE'S THERMOSTAT. 



t. tfir— NO. XKKiri. 



sans 



MAGAZINE OF SCIENCE. 



DR. URE'S THERMOSTAT. 

TiicnMMftT \T is the n.imr of an Rppanitti* for rrgu- 
Itttiiif; icmpemlure, in vuponxation, tlutilUtioiit 
Jieatiui; bntbs or hutliouscs, venlilKUng ■partmentf, 
Ax. ; and for wliich Or. Urc obtained a patent 
in the year 1831. U operates npon the phv^ical 
prioctpte, that when two Ihin mrttillio hdr* of dif- 
ferent rxpansibilitica are riveted or soldered facewise 
tottrther, any t-Lange of temperature in tliem will 
L*auM- u Hrniiihle movemetit i>f tlexurc in the com- 
pound bar, to one tdde or the other ; which moi'e- 
mtrnt tn^y hv mnde to operate, by the intrrvcntion 
of levers, ^tc, lu any desired degree, upon valves, 
itopcot'kv, vtove-registeri.air'Veiitilatorx.LHcc. ; bo na 
to rcguUtc the t(*mpernture of the medium in which 
the said compound bnrs are placed. Two long 
niliTfi, one of steel, and one of bard hninmered brass, 
rireted together, answer very well ; the object being 
DQl&iinply to indicate, but to control or ntoiti/y tem- 
perature. 'Hie foregoing diaiframfi illustrute a few 
out nf the numiTous applicstioni of thtfl instnimrnt. 

Fig. I. A B ia a aiu^jIr thennoatattc hiir, ronnist- 
iriff of two or more bar* or rulers of dilTerently ex- 
pansible solids (of whiob, in some casea, wood may be 
one) : these bars or rulers are Armly riveti^d or 
soldered together, face to face. One end of the 
compound bar is Bied by bolta at A, to the interior 
of the containing ristern, boiler, or apartment 
ALMB, whereof the tempeialure lias to be re- 
gulated, and the other end of the compound bar at B, 
is left free to move down tovrards C, by the llexure 
whichwill take pUce nhen ita temptrature is raised. 

Tlie end B ia connected by a link B 0, with a 
lever D E, which is moved hy tlie flexnre into the 
dotted position B G, cuuslnjc the turning-vaWe, 
Bir.%ei(lila(or, or reRiitrr, ON, to revolve with a 
norrrspooding angular motion, whereby the lever 
will raii'P the equipoised slide damper K I, which ia 
suspended hy a link from the. end K. of the lever 
K D. into the position K H. Thus a hotboase or a 
watcr-buth may have its temperature regulated by 
the ronlcinporaDcous admission of warm, and dis- 
charge of cold air, or water. 

Pig. 2. ABC is a (faermostatic hoop, immeraed 
hnrizontally bcneat% the surface of the water-bath 
of a still. Tiic huop is fixed at A, and the two ends 
U C sre connected hy twn links B D, CD, with a 
straight sliding rod D H, to which the hoop will 
f!;ive on endwise motion, when its temperature is 
altered; E is an adjusting screw-nut on the rod 
DH, for setting the lever FG, which is fixed on 
the axia of the turning-valve or cock F, at any de- 
sired position, so that the valve may be opened or 
shut at any desired temperature, rorrc-sponding to 
the widening of the points BC. and the consenU- 
neous retraction of the point D, towards the cir- 
camference A B C, of the hoop. G H is an are 
graduated by a thermometer, after the screw-piece 
E baa been adjusted. Through a hole at H, the 
guide-rod paiaee. I, la the oold-water cistern ; 
I F K, the pipe to admit cold water; L, the over- 
flow pipe, at which the excess of hot water runs off. 

Fig. 3, shows a pair of thermostatic bars, bolted 
fast toj^cther at the ends A. The free ends B C are 
of unequal length, so as to act by the cross links 

F on the stopcock K. The links are jointed to 
[fhe hahiUe of the turning plug of the cock, on op- 
tosite eldea of its centre ; whereby that plug will be 
[tamed round in proportion to the widtuing of the 
.tminta Q C, U G i< the pipe ^cominumcating with 
the stopcock. 



' Suppose that for n;rtjun pnrpitsra in pfaifmscy, 
dyeing, or any other chemical art. a watn litd, u 
refjuircd to be maintainrd itcndity at a :' 
of IM)'' F. : let tile combined tbenu' 
hinged together at E F, Fig. 4, be pi 
bath, between the outer and inner veas' i 
being bolted fast to itie inner resiel at G ; 
their sUding rod K connectc<l by a link witit A] 
li^ed up<m the turning plug of the stopcock I, 
introduces cold water from a cistern M. thr( 
pipe M I N, into the bottom part uf the bath, 
length of the link must be so adjusted 
flexure of the bars, when they are at a temj 
of 1.^(1', will open the said stopcock, and w 
water to paaa into the bottom of the batb 
the pipe I N, whereby hot water will be di 
at the top of tlie bath through an op 
pipe at Q. An oil bath may be rr-ruUted 
same plan ; the hot oil overtlowing from Q, 
refrigeratory worm, from which it may be 
to tlte cistern M. When a water bath is h( 
the distribution of a tortuous steam |itpc thrc 
as I N O I', it will be necessary to [■ 
of the thermostatic bars with the 
ing plug of the steum-cock, or of L _ 
I, in order Lbat the bars, by their dcvnfc, 
or open the steata passage inorv or leas, 
as the temperature of the water in the bath 
tend more or less to deviate from the pit^ih to 
the apparatus has been adjusted, Tlie water i 
condensed steam will pass ofl' from the 
winding-pipe I N O P, Uirough the sloping i 
A saline, acid, or alkaline bath baa a boillacj 
perature proportional to its degree of concent 
and may therefore have its lieal regulated bf I 
mersing a thermostiC in ic» aad connecting 
working part of the instrument with a a(o( 
which will admit water to dilute the batb vl 
by evajwration it has become couceotnitcd, 
acquired a higher boiling point, 'ilie apace tut\ 
batb, between the outer and inner pans, 
communicate by one pipe with the water ctstarvl 
and by another pipe, with a safety ciatam Bf T 
which the batb may be allowed to overflow 
any sudden excess of ebullition. 

Fig. 5, is a tbemiostatiu apparatus, 
three pairs of bars D D D, which arc repi 
a state of flevure by heat ; but they become : 
straight and parallel when cold. ABC ia a 
rod, fixed at one end hy an adjusting aoi 
the strong frame FE. having deep guide 
the sides. FG is the working-rod, which 
endways when the bars D D D operate by 
cold. A square register -plate 11 G, may be 
to the rod F G, so as to be moved bacl 
forwards thereby, according to the 
temperature ; or the rod F G may cause tlie 
turning air-register I to revolve by rack and* 
work, or by a chain and puUej. The regist 
H G. or tnming register I, is situated at the I 
or upper part of the chsmber, and aerrei to I 
hot air. K ts a pulley, over which a oord 
raise or lower a hot-air register L, whieh 
situated near the floor of the apartment or be 
to admit hot air into the room. C is a milledj 
for adjusting the thermostat, by means of thej 
at E, in order that it may regulate the tern] 
to any degree. 

Pig. 6 represents a^htmney, fumubrd 
pyrostat ABC, acting by the "links B D E G1 
damper F H G. The more expansible metsll 
the present example supposed to be on the 



MAGAZINE OF SCIENCE. 



259 



of the (lamprr-plate will, id this cue, \>r 
lore directly into t)io passu^c of the draught 
'ic oliimney by increase of tempcratare. 
^reprueats o. circuUr turninf; rrgiiter, auch 
for a ftore, or itOTr*gjatc. or for venli- 
irtincntJ : it it fumi»lifil with n leriea of 
thermostatic bara. each bar betn; 6sed fact at 
:cuinfcTence of the circle B C, of the fiicd 
of the air-re^'ster; and atl the ban art in 
t at tbe centre A, of the twining part of the 
r, bj thrir ends beini; inserted between the 
€ a imatl pinion, or by being jointed to the 
part of the turniiiff pbite hy umall pins. 
8 repreaenta another nrrangement of this 
mtNtic appiratQB applied to a eircolar turning 
r* like the preceding, for venidatinK apnrt- 
Two pairs of compound bars are applied 
> act in euncert, by means of the Hnks AC, 
n the opposite endd of a short lever, which 
I on the central part of the turning plate of 
•regiater. The twa pairs of compound bars 
m fastened to the circnmfcrcnce of the fixed 
Kthe turniii* register, by two slidiag rods 
K which are furnished with adjusting acrewa. 
Rtion or llexare ia transmitted by tbe linka 
C, to the turning ptnte, about its crntre, 
^orpose of shutting or opening the v^ntt- 
>rial ajMrtures, more or leas, acrorJtng 
ipermture of tbe air which surrounds the 
lo laming register. By adjusting the 
>, and U C. the turning register is made 
tl its apcrtnrca nt any desired degree oT 
; but whenever tbe air is a1>i>ve thi>t 
the fleiure of the compound bara will 
IpertureM. 



SEA-HORSE. 
Di.*B. machine, called bjita iaTentnr AVv/f/e 
^riagf, hut which wo think merits the more 
|»Ce title of .Sea-horse, hns been described 
fe lud before the Academy of .Sciences by 
plumps. " It is intended to aid vessels in 
\ bottcver violent the weather, and ia sttatAtl 
imposed of t caae of sine, strengthened with 
^ of wood, of which the perpentlicular 
,<itcali and terminated at the bottom 
■on oi ' appendix.' Its length is 3| metres, 
cubic contcitta ohout ICOU litres ; its lop ia 

Eoll its length with a saddle, baring u 
of stirrups as the nnntiie is intended to 
in auch a manner that they sit upon this 
U men oa horseback. Six men arc placed 
uutilc. of which three manage the wheels 
ilcttei in wood or cloth, which have their 
cr, not in tlie water, but in the air. This 
if propelling boata has already brren put in 
OQ '.ht.* Seine, in 1785, with complete auc- 
Irhiiii the oantile ia attached a cord, winch 
d imm the boat, nnd when the men havo 
the shore, they draw, by means of this cord, 
which they fasten on tlie shore, and thua 
Ikowt OD the vessel to readi It." Tbe in- 
lays, let the wind and wcAther he. what it 
) ship can be reached by the nautile. and 
:hr iiiiirlii:ir hr turned by tbe violence of titc 
side, it will, from \i& construe* 
.•11 I, and OS the men it carries are, 

ujuicti to the saddle, all that they will 
twill be % moroeotary dnckitig, — Invrnior^' 




SOLLY'S ELECTRIC THERMOMETER. 

CAiMrtiu-^l tu (he Etiitor tif the PhitotopAical Magnnjn: J 

SiR.~I om induced to give you the following Ac^counC 
of a tittle thermo-electric arrangcmr.at, believing that 
it may be interesting to some of your readers ; for 
although there is Uttle or no novelty in the prfnciplea 
on which ita action depends. I am not aware that 
it has bccTi before practically employed : — 

" I had for aome time experienced conaiderobta 
inconvenience in coiiductiog certain experinents 
requiring a long •continued and uniform degree of 
bcjit, from tbe difficulty of regulating the tempe- 
rature of my furnace, and the constant uncertainty 
whether everything wu ))rocceding satiafactorily 
during my absence from the laboratory. 1 had in 
consequence often tliongbt of the possibility of so 
arningiog a little thermo-electric apparatus that it 
might serve as au index of the rate of combustion 
and consequent beat of the furnace, by the deflection 
of a galvunometer at a distance from the source of 
beat, A amall thermo-electric battery might bo ao 
plar^ that the one teriea of jointa or solderlngs 
«honld be consuntly exposed to the heated surface 
of the furnace ; but a serious obstacle presented 
itself to any contrivance of this kind, which was 
llie difficulty of keeping the alternate jdnta of the 
battery cool : a current of electricity would doubt- 
less be evolved in conaequcnce of the difTcrencc of 
temperature existing between the two sides of the 
battery, hut of course as the heat would gradually 
traverse from the hotter to the cooler side, it would 
greatly diminish and modify the results, and thua 
present false indications of temperature; whilst 
even if it weru possible in keep the one side of tho 
battery cool, (hither by water or by any other meann, 
yet the value of the deflection of the galvanometer 
would be uliAnys unccrtaio, ss the difference between 
tlie two sidej of the battery could never he ascer- 
tained unites the exact leduoliuo of temperature 
thufi caused were rorrcctly known. 

•' .\fter one or two unsacoeseful attempts to over- 
come ih'u objection, I Uid aside the battery and 
substituted in ita place a single pair of metallic 
elements, which I found gave abundance of power, 
and was not liable to tlie defect which the use of 
the battery involved. 

" A piece of copper wire, one twenty-fourth nf 
an inch in diameter, oud of sufficient length to reach 
from the fornace to my ordinary sitting-room, wna 
joined by twisting the ends to a nimiUr wire of aoft 
iron, the ends of both bavins been previously well 
cleaned with sand-pnper. Tlie two wirea wrre thou 
secured in a convenient manner by small oaili to 
the walla of tbe rooms they had to pass through, 
care bcint; taken that they were not anywhfre in 
contact with each other, except at the two extreme 
pointa of junction ; the one of these was so placed 
in the flue of the furnace that it was completely 
exposed to the action of the hot air and smoke at 
that part where tbe Bue left the body of the furnace, 
whilst the other joint wns in my room in contact 
with a thrrmometer, and surroundeil nith cotton, 
BO as to render it us little as possible liable to sudden 
changes of temperature. The copper wire was then 
divided about a foot from the joint thus protected ) 
the two ends of the wire were connei*tcd with the 
extremities of a galvanometer coil, and the apparaloa 
was complete. 

*' .\ metallic circuit was thni made conaiating of 
two elements, tlie one being the Iron wire, and the 
other the coi>p<:-r wire, including the additional 



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MAGAZINE OF SCIENCE. 



length of copper wire in the coU of the galTanometer. 
The onf joint ur point of contact was of ooime 
alvrays far hotter than the other, and woatd nc 
eesMrily remain w, bo long as the fiiel la the 
funisoe contitiiieU to burn, and would be dependent 
on the rate of combosUon in tlie furnace ; whilat 
the other junction wonld always remain very neartjr 
at the trrniperatnre of the air, and it* rariations 
could be readily known by the thrrmometcr in con- 
tact with it. A current of tlcctricity was thus 
,grnernled. proportioned to the di.Tcrence of tempe- 
ffHture bctwei'ti the two joints, and a deflection of 
le galvdnoincter was causrd, which increaied when 
the fiimnce became hotter, decreased when it 
eofiird, and at all tirriei indicated accurately the 
chnnf^es of tempcratnre taking place, thua giring 
me a thermomi'ter which indicateft, without my 
moving from the table, the exact rate of combnfltion 
going on in the furnace, which is Afty yards distant 
from the indicator. I beliere that it is comuiotily 
supposed that weak thermo-electric cnrrcuta cannot 
be well made to traverse small wirea of any length, 
and this is probably the reason why this beautifully 
manageable power has been so Utile employed for 
practical nccs. 1 hare received ao much natiiifactton 
fr(im the arrangement just described, that I am 
cunvittccd it would be found a very useful indicator 
of temperature in stoves, flues, and hot pipes, in 
many situations where a common tbertnometer ia 
Inapplicable. 

*' The coat of snch an apparatus mnst necessarily 
Ire more expensive than any thermometer, but (hen 
it uinst be remembered that it does far more than 
«n ordinary thermometer, giving us the means of 
i.ii'.'^ving tbe temperature of a Htove or furnace at a 
tliKiJiice, giving ui indications of thr least change 
or variation in the source of beat, with even greater 
certainty and distinctness than a thermometer; and 
bnides, showing these changes ao rapidly that we 
^know whctlicr it is becoming hotter or colder, 
before a thermometer placed on the outside of the 
stove indicates any ctiange. I have observed, on 
comparing the thermo-electric with an ordinary 
thermometer placed on the iron plate forming the 
top of the furnace, that if the ash-pit door were 
eloied, or the draught iti any other way diminished, 
the dc'llectton of the galvanometer was immediately 
rrduced, whilst the rxtemal thermometer continued 
to rise for some httlo time ; and that tbe indications 

Sivcn by the galvanometer of the augmentation or 
ecrease of temperature in the fumncc, always pre- 
ceded the some indicaUons from the mercurial 
thermometer on the top." 



THE ORGAN OF TASTE. 

DT M. DO.NOVAN, EBa. 
fhctumed/rovi jtagt 8Mt. an4 amctuded-J 
Ik eoliitory comhinations of food, ipicei and other 
atimulants are used, not merely for tbe purpose of 
imparting their own flavor, but with a view of ex- 
citing the organ of taste to the perception of the 
flaTor of the meats, Ike. of which tliey iirr rnmpoeed, 
In a higher deg^ree than it would otherwise have 
been. It is not the biting quality of pepper alone 
that is valued ; and wine is not used in aauces that 
its tule, as such, may be jMrceived. Tbe perfec- 
tion of the art of making culinary combinations is 
the production of a trriium quid, in which the 
elementary flavora are nil lost and indistini;iiiihable 
ill the new one created by their combined effect on 
tht palate. 



When the flavor of an edible aobatonoe is 
delicate and peculiar, the palate abot^d nervr 
excited by powerful stimuli, either prerioufy or] 
liffloltaneouily ; for powerful stimuli act u fft-j 
parativea to other active ones only. There ore natfi 
instances of this ; the natural flavor of 
when in highest perfection from a proper I 
one in which may be di«tingm»he^ that of 
delicate oyster ; if it be peppered, the ojitaj 
is entirely lost. Again, a cacumber olicad, 
rately aalted, and well drained, !>^* " *trii^ 
mixture of the flavor of a c«> 
destroyed oa soon as vinegar and j 
If drcMcd cacumber be eaten at the umc 
kidney -beans, tlie latter lose the whole 
peculiar taste in a singular manner. 

Tbe temperature at which impresftons art] 
on the organ of taste is of conaeqneoce, 
considerably modifles them. Every one mi 
remarked that salted meat is much more 
hot than when cold ; and that spices have 
power at a high than a low tempcmturc. A 
quantity of pepper, eaten with an oyster 
freezing temperature, will rxert but little 
the paUte, while the same quantity on on e^i 
of lobster, heated very hot, will be ex( 
gent : on this account flavora are often 
by mere increase of temperature ; thus 
coffee is always preferred to the same artic 
warm : the perfection of a dinner, with 
sons, is to have it served as hot aa con ht\ 
those who wish for the stininlna of brandy 
palate, without its iutoxicating effect, driok iti 
diluted, but at a scalding heat. Delicate 
are not appreciated at high beats: thus the 
kindH of tea do not bear to be drunk at a beat i 
110^ witltout loss. 

A very low temperature is olwvys au£ri« 
the perceptions of tastes, and eeen pungfli| 
of^en become insipid. This is strongly exei 
in a circumstance stated by Captain Paf 
party, that had lost their way in Melville 
daring an tntrose cold, observed that a mitl 
rum and water *' appeared perfectly 
clammy.'' The best household bread, if 
to the temperature of 28'*. will be found 
the mouth : it has its beet flavor at &0\ 
persons an oyster is in its most agreeable state < 
raw : at the temperature of 70"^ or d<r it i« nit 
perfection, the want of sufficient coldnesa is 
perceptible : yet at 32*^ it is just aa hod, and 
inferior to the aame oyster at 48*^. 1 waf 
make this trial by reading a pasaage in nisy«J 
he suyi, that [the Romans cooled their oj 
ice : to me it appears that 48° ii the tcB| 
best calculated to develope the flavor. 

A draught of cold spring-water ta dsll| 
summer, not merely on nccuunt of its coU 
on account of ita appu'ent ^eedom from oU 
Here the organ judges under the deorpCil 
paralysing influence of cold; for let aooAt 
same water rise to the temperature of 70^, 
will evince that it not only pnasesied a taste 
disagreeable one. Scarcely any water 
directly from springs is free from a mineral > 
and this is chiefly disguised tiv iLiculdorvA. 

Some kinds of bad port 
icing : for tbe retluction of i . irat 

organ less lensitive. 7*he i^iav wcatmeiii 
virtually lessen the fine flavor of good port; 
hence such ought not to be iced. To rrJuft 
port to 32^ would not only render it utuUtly. 



m^^ig 



MAGAZINE OF SCIENCE. 



U ecHUUtini; of Vme, potaib, anil Urtaric acid, 

be precipiUled, bat it would lock up its 

u it it erprfiuil : it may, however, be ad> 

iiisly cooled down to ■15'^ or 50"; for then 

firafier decree of sapidity ii developed. Madeira 

nd wines of ^eat body bear a slight elevation of 

t».n.i,-t ..ti.rr ; and iulTer an agreeable devrlopemcDt 

•porkling Champagne, on the other hand, 

'i by cold, for it then l>eut'r retnina ii3 

ucbuiuc acid when poured out ; and, althouf^b in 

tlui f ute it effervesoea leas briikly in the glasi, the 

oC tbe cwbooic acid, one of its important con- 

ktfl, ia rendered more perceptible. Hut even 

Itlna wine mach Icing locks op the flavor. 

In tome imtancea tbe desir«d efTect i« produced 

reiaetDg the temperature of part of the mouth, 

'iutead of oooliag the liquor. The taate of porter 

li S^st at a medium temperature : in warm weather 

• ' lered, by persons who are fiuitidiaiu In 

>)!«, to be improved by being <lrunk out 

a mcimijc vestcl. The roetal, being an excellent 

»rof heat, on being applied to lite lips causes 

ntnr.bineoua nub of heat from all parts to re- 

' riniiibrium, and tbe porter ia received 

"uth while tbe nervca are at a lower tem- 

, and thercforo the liquor tastcc to more 

;. At least thia is as good a theory as tliat 

Ka* beeti long since adfanced, in which the 

lent of porter drunk out of a metallic 

•ttributed to the aj^ency of galvanUni. So 

ia the or^aa of taste in this respect, that 

bqnor be covered by a foamy head, which ia 

'b«d conductor of heat, it intercepts tbe pas. 

of beat from the upper lip, and hence feels 

and becomes diaagrecable whether the vessel 

ic or not. 

organ of smell is allied to tbo organ of taste, 

ty asalc^ous phenumena are found to affect 

if. In an experiment made by Mr. Bojie. 

l-aeed, iufused on Che juice of apples, af- 

ratik a smell of garlic, that no one would 

:; yet neither of these substances has a smell 

IftUghteat degree resembling garlic. 1 have 

that if one first aroells to some highly rec- 

iphtba, obtained from connel-coal, and im- 

ly after to some spirit of vegetable tar. 

w«U rrctified, the odour of the latter will 

eomptetely changed, and resemble a perfume 

eh the uuil of Uveader is very striking. 



TlfE PICTURESQUE IN PAINTING, 

lUft beautjr," sajrB a Iste writer on that 

rtCtrs to such beautiful objects as are 

[lothe pencil." This term, although princi- 

iproprifltcd to the works of nature, is not 

with reference to many of the pcrfor- 

of art. Those objects best merit the appel- 

(of tbe former class) which arc distribntcd by 

of nature with a mixture of grandeur, 

Tt and varied rudeness. A nrat ordinary 

gmrden, for instance, although a cheerful 

ible object, abstractvdJjF considered, yet 

too great a proportion of uniformity, of 

oat of (UriffH, to be fairly characterized 

■teturaacyue. "The ideas of neat and smooth," 

Vlpin, " instead of being picturesque, 

:y the object in which they reside 

1-.,, ,...>-^..eioni to picturesque beauty. Nay. 

kCf, w* do not srruple to assert that roughntsea 

Utk» moat easential point of difference between 

UMUifal aod ihe pictoreeque : u it ippeora to 



4 



be that particular quality which makea objects 
chiefly pleasing inp^tiug. We use the general term 
roughneu i but, properly speaking, roughness re- 
lates only to the surface of bodies ; when we speak 
of their delineation we use the term ruggednttf^^ 
Both ideas, however, equally enter into the pta^| 
toresquetand both are observable in the smaller a*' 
well us in the larger parts of nature ; In the nurline 
and bark of t tree, as in the rude summit and 
craggy sides of a mountain. 

** Let us then examine our theory by an ftppeftl 
to experience, and try bow far these quidities enter 
into ^the idea of picturesque beauty, and how far 
they mark that ditrcreiice among objects which ia 
the ground of our inquiry. 

" A piece of Pallodion architecture may bo ele- 
gant in the last degree ; the proportion uf ila parts, 
the propriety of its omampnts, and the aymmetry 
of the whole, may be higtdy pleasing ; but if we 
introduce it into a picture, it iuiiiicdiately becomes 
a formal object, and ceases to please. Should we 
wish to give It picturesque beauty, we must use the 
mallet ioateod of the chisel : we must beat down 
one half of it, deface the other, and throw the mu- 
tilated members around in hemps ; in short, from m 
smooth building we must turn it into a rough ruin. 
No painter who had the choice of the two objects 
would hesitate a moment. 

"Again, why does an elegant piece of gardi 
ground make no figure on canvass ? — Tbe shape 
pleasing, the combination of the objects harmonious, 
and the winding of the walk in the very line of 
beauty. Ail this is true ; but the smoothneu of 
the whole, though right and as it should be in na> 
ture, ofleiids lu picture. Turn the lawn into a 
piece of broken ground, plant rugged oaku instead 
of flowering shrubs, break the edges of the walk, 
live it the rudeness of a road, mark it with wheel 
tracks, and scatter around a few stones and brush- 
wood ; in a word, injitesd of making the whole 
smooth, make it rough, and you make also it pic- 
turesque. All the other iugredienti of beauty it 
already possessed." 

Picturesque compositioD may be defined, to speak 
generally, as tbe art of uniting, in one whole, a 
variety of parts, which parts may be sought and 
found among the works of art, (though in a far less 
proportion,) as well as in the works of nature. 
Objects may likewise be made picturesque : this, 
however, is buxanlous work, and there is no small 
danger of missing the picturesque, and foiling into 
the ridiculous. Artificial mint, for example, can 
seldom he regarded as matters of good ta<ite ; 
when the trick is known, the eye, or rather 
imagination, through the medium of tbe eye, refua 
to recognize therein any of tbe principles of romotitic 
beauty sought to be imparted. The great source of 
picturesque beauty is nature in all her original va- 
riety and irregular grandeur. ** We seek it," says 
the ingenious authority ((uoted 'above, " among 
the ingredients of landscape — trees, rocks, broki 
grounds, woods, rivers, lakes, plains, volleys, mot 
tains, and distances. These objects, in themselvc 
produce ioflnite variety ; do two rocks or trees 
exactly the same — they are varied a second time by 
combination, and almost as much a third time by 
different lights and shades, and other serial eflecU. 
Sometimes we find among them the exhibition of a 
whole, but oftener wo find only beautiful parts." 

Grandeur or sublimity, unassisted, cannot elevate 
an object to the character of picturesque ; howcve^ 
grand tbe mountain or rock may be, it has no ' ~ 



uMeiH 



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MAGAZINE OF SCIENCE. 



to tbi.H rptthet, onlffu iU form, its color, or iU nc- 
coropanimenU hnve lome degree of beauty. Nothing 
cAn be more subHme than the ocean ; bat, wboUj 
unaceompaiueil, it hu little of the pictaretqae. 
When we tslk, therefore, of a sublime object, we 
always unilerstAiid thnt it in eIro beautiful ; and we 
call it Miblime or beautifat only as the ideas of stib- 
Umity or »ireple beauty prevnil. Bnt it is not only 
the form and composition of the objects of land- 
scape whk-h the picturesque eye eTomines : it coo- 
nectM them with the atmonphere ; and neeks for all 
those Tsrionft effects which are produced A-om that 
▼ast and wonderful storehouse of nature. Nor is 
there, in travelling, o greater pleasure, than when a 
scene of grandeur bursts unexpectedly on the eye 
accompmierl with some aeeidentAl circumstance of 
the atmosphere which harmoaixes with it and gives 
it double value. 

Few are the places so barren and destitute as to 
aff'rfd nothing from which materials may be ex- 
tracted hy the lover of the picturesque. 

The grent military road between Carlisle and 
NewcAStle i«, perhA]ts, th? most barren tract of 
Goantry in England : "yet even here,'' says Gilpin, 
" tliere is always something to amuse the eye. The 
interrtiangfAble patches of heath and greensward 
make an agreeable variety. Often, too, on these 
vast tracts of intersectiii^ grounds, we see beautiful 
lights softening off along the sides of hills; and 
often we see them adorned with cattle, flocks of 
fthe(*p, lit^alli-cocks, gronsf, plover, and flights of 
other wild fowl. A group of cattle standing iu the 
■ha«lr on the edge of a dark hill, and relieved hy n 
lighter distance beyond tbcm, will often make a 
complete picture, without any other accompaniment. 
In many other situations, also, we find them won- 
derfnlly pleading, ond cnpoble of making pictures 
amidst all the drticienries of laniiticape. Even a 
vrinding rood itself is an object of beauty ; while 
the richness of the heath on either side, with the 
little hillocks and mimbling earth, give many on 
excellent le^ton for a foregroaod. When we have 
no opportunity of eiamining the grand scenery of 
nature, we have, at least, everywhere the means of 
observing with what a multipliritj of part5, and yet 
with what a general simplicity, she covers every 
surface. 

'* But if we let the imnginatinn loose, cren scenes 
like these administer great amusement. The imngi- 
nation mn plant hilU, can form rivers and lakes in 
vnllvys, can build castles and abbeys, and, if it find 
no other nninsement, can dilate itself in vast ideas 
of apace." « 



STRENGTH OF MATERIALS. * 

(Fntm .inyttl't •' titrm^ntt nf I'fijftira.-') 
** Strknoth depends on tbu mngnitudo, form and 
position of bodies, ns well as on tbe dej^ree of co- 
hesion in tbe moferial." 

0/ aimilar bodies the largtH it proportionaUy 
the treakcff^ — Sappotic two blocks of stone left 
projecting from a ruck that has been hewn, of which 
blocks one is twice as long, and dtrep, and brosd as 
the other. The larger one will by no means sup- 
port OS much more weight at its end than the other, 
M it is larger; and for two reasons: — I. In the 
larger, each particle of the surface of attachment, 
in helping to bear tbe weight of the block itself, 
has to support by its cohesion twice as many par- 
ticles beyond it, in the double extent of projeclion, 
as ■ psrtide has to support in the shorter block ; — 



and, 2, both the oddttional aulistJiiice, ooii toythiaf 
appended at tbe outer uta'mity uf the luftr, atv 
acting with a double lerer adrautage to break it, 
that is, to destroy the cohesion. Ilenee, if soy 
such projection be carried out Tcry far. It will bicai 
off or fall by ita own weight alone. 'Vhat is l^ 
true of a block supported ai one end, is equally tim 
of a block supported at both end* ; and, tndnJ,^ 
all masses, however supported, and of wbstrnr 
forms. That a Urge body, therefore, rosy hun 
proportionate strength to a smaller, it must be mail 
Btill thicker and more clumsy than it is made lotifB; 
and, beyond a certnin limit, no proportions whst- 
ever will keep it together, in opposition tDeK^ff 
to the {orci of its own weight. This great tnu 
limits tlie sice and modifies the shape of '■- ■ ' • ■" 
durtiOQS of nature and of ort, — of J.i 
animals, architecnirsl or mrchanicol stru< 

Hitlt. — Very strong or coheuive material iw^ 
form hills of sublime elevation, with very proj^. 
ing cliffs and very lofty pfrpendicular y 
and such are seen, arrordingty, wherir 
granite protrudes from the hnwela of the 
in the Andes of America, tlie Alps of K 
Himaluyas of Asia, and the Mountains ol . _ , 
in Central Africa. But material of inferioritrmitk. 
exhibits more humble risinp and more rntinef^ 
surfaces. The gradation is so striking sn<l 
from gmnite mountains down to those of 
gmvel, or sand, that the geologist can gener\i)} aii^ 
the Kobataoce of which a hill is composed ^ te: 
|)«cuHaritie8 of its shape. Even in granite ttsiA 
which is the strongest of rocks, there is a luiJt to 
height and projection ; and if sn instance of either^ 
much mure remarkable than now remsjus on esilhi 
were by any chance to he produced again, tho \Kt 
which we nre considering would prune the oaD> 
stroaity. The grolenqoc tigorea of rocks and mooo* 
tains seen in the painitiigs of the Chinese, or scto- 
ally formed iu miniature for their gardfi 
press their notions of perfect aubhioity nn 
are caricatures of natare, for which on. 
never havn existed. Some of the smal-i 
in the Eastern ocean, however, and b<'i 
mnuntiuns of the chains seen in the voyv. 
Chino, along the co&sts of Borneo and i 'iiim*b» 
exhibit, perhaps, the very limits of postnUiUty Ifl 
singular shapes. In the raoun, where tl<i- vfrir?il 
of gravity of bodies is lets than on th'- 
accuunt of her sroallcr siie, roountbtos ■ ' ■■ 

many times higher than on the eaKh ; sitd uUed^H 
tion proves that the lunar mountains are <*'l^^| 
higher thon ours. Hy tbe action of win ' 
currcnis. ond frost upon the mineral m&- 
us, tliLTO is unccitsingly guing on an ui 
and wasting of supports, so that cver\ 
then immense rocks, or otmoit htUf, «t. 
gravity from tlie station which they buvc > 
the earth received ita present fnrm, an . 
obedienue to the law now ejiplained. 

The sise of rtgetablet, of courM. b obedieat lo 
the same luw. We have no treri r* ' - i— i.^ 
of 300 feet, even when perfectly p. : 
sheltered In forests that have been ll 
the beginning of time; and oblique or 
branches nre kept within very narrow lim 
great strength required to support them, 
that, to have proper strength, the breaii 
meter in bodies most increase moreqm 
the length, u well illustrated by the coDti 
ing between the delicate and slender propt..i — .- — 
a young oak or elm, while ytt in the •eedMOi't 



to n. 

■■ M\\. 



MAGAZINE OF SCIENCE. 



363 



BZhl tti itard]r form wbea it bu braved for 
all the winds of beAven, aud hiu becuue 
rch of the p»rk or forrat. 
|2« farnisU otUrr iutcreE'ing illiutrattons of 

now mufeivr nnd clumsy are the limb* 
pbaiit, the rhinoceros, the heavy on, com- 
b the ftlender forms of the itnj;, antelope, 
loond t And an animal nauch larger than 
■nt would fall to pieces from its own weight 
lileas it4 bones were made of rauch stroDgor 
, Many hare questioned whether the 
k, or sntediluviftii clephnut, cuuld bavi; 
Iry land, or mast have been amphibious, 
mt b<idy might generally be borne np by 
Hie whale is the largest of animals, but 
iu mighty weight because lying coDetimtly 
Old support of the ocean. A cat miy fall 
unity where an elephant or ox would be 
I pieces. The giants of the heathen my- 
poald not bave existed on this cartli, for 
hich we are now considering; although 
Boon, where, as already stated, weight is 

such beings might be. In the planet 
kgain, which is many times larger tlun the 
ordinary man from hence would bo carry, 
r simple weight of his body, a load luffi. 
ETush the limbs which supported hiui. The 
litt/f compact man, poinia lo the fact that 

is stronger in proportion to hiy size than 

1. The same Uiw Itmjla the height sod 
if arcliitectural structures. In the bouses 
n atorirs, which formerly stood nnilt'r the 
Edinburgh, there was danger of the super- 
It vaU crushing the foundation. 

Wcatminslrr hill upproaches the limit 
that is posaible without very inconTenient 

or central supports ; and the domes of 
e* of St. Peter, in Rome, and St. Paul, 

, are in the same predicament. • 

Hf a Briiiye, — A fttonc arch much larger 

of the magaifioent bridges in London, 
in danger of cruihtng and splintering its 

r— The ribs of timbers of a boat have 
I hundredth part of the bnltc of the tim- 
l ship ten timet as long as the boat. A 
|d (A ninety feet contaios, perhaps, twenty 
much wood as a yard of thirty feet, and, 
p, is not so strong in proportion. If ten 
m do the work of a three-hundred-ton ship, 
m tbao three times that number will be 
to manage a ship three times as large. 
p ships, such as the two built in Canada 
|ar 1825, which carried each nearly 10,000 
weak from their size alone ; and the loai 
first specimens of gigantic magnitude 
ar%ge the building of others Uke them. 
(Tube amtinueiLj 



RVATION OF BOOKS FROM 
INSECTS, 
ctw BibtiophiltM of HainauU hare 
medal, worth one hundred francs, 
or of the best mf!moir forwarded to the 
answer to the following question : 
the best means of totally preventing the 
)f the insects .which destroy books ?" llie 
I Bimexed to the success of the pnper is, 
pieana proposed may be applied easily, and 
to oil libraries large or small. 
to qSt Ihnt in making ihii proposal, the 




■ociely hu not reflected tlwC it will giro a Tory 

difficult tiuk to the commisaiun appointed to decide 
on the merit of the diflcrent papers sent in. Let 
us euppoBQ that several persons recommend each a 
different process. How is the society to test the 
respective value of these communications ; how are 
they to judge if they are suitable, or if tbcy hU&l 
exactly the object proposed ? The ravages of insects 
in books are never Instantaneoas ; it is only after 
the InpM of some time, more or less long, tluit it is 
possible to perceive traces of them on the pnper. 

We uru convinced that esstrntial oils aud strung 
perfumes would preserve a book for a length of time 
from the cause of destructioa, to which the question 
of the b^ociety refers ; but to be assured of the con- 
tinued existence of these perfumes vrould require ao 
observation of many years. 

Amongst the means of preservation which ap- 
pears to us best, we may cite the following: — \. 
To introduce in every volume some leaves of an 
herb, of small expense, and strong and penetiating 
smell. 2. To submit the books to the vft|HJur of 
essential oils in a state of ebullition. 3. To line 
the interior of the covers of every hook with sheets 
of tanned shfepskin or paper, in the preparution of 
which lue should bu made of substances of a strong 
odoriferous smell, and in the course of time to 
rcbind them with materials of a similar description. 

As we are on the subject of the preservation of 
books, it appears to us, that the printers of the 
present day do not work for posterity ; for they 
employ a species of paper containing a germ of 
destructioa, which, although it acts slowly, is not 
the less certain in eificct. We allude to the cldoride 
of which use has been made for some years, for the 
purpose of whileniog the pulp, which serves to pre- 
pare the different sorts of paper intended, as iveU 
for printing, os for ordinary use. 

This strong agent not only takes Grom tbe paper 
a portion of the strength which it possessed under 
the old process of bleaching, aud which may easily 
be perceived by comparison of the paper of our 
modern books, which can be easily torn, with the 
tough paper of the books of the lust century \ but it 
also enters into intimate combination with the pulp, 
and this union will have the effect of reducing to 
powder in the course of twenty years the books of 
the present day. — La FeauU, 

ATMOSPHERIC REFRACTION AND 
REFLECTION. 
Not <>nly every thing we bear, but all we see. Is 
through the medium of the atmosphere. Without 
some knowledge of its action upon light, it would 
be impossible to ascertain tbe position of the hea- 
venly bodies, or even to determine the exact phice 
of very distant objects upon the surface of the earth ; 
for, in consequence of tbe refractive {fewer of the 
air, no distant object is seen in its true position. 

Ail the celestial bodiea appear to be more elevated 
than they really are ; because the rays of light, in- 
stead of moving through the atmosphere in straight 
lines, are continually inflected towards the earth. 
Light passing obliquely out of a rare into a denser 
medium, as from vacuum into air, or from air into 
water, is bent or refracted from its course towards 
a perpendicular to that point of the denser surfaee 
where the light enters it. In the same medium, 
Ibc sine of tbe angle contained between the incident 
ray and the perpendicular is in a constant ntio to 
the sine of the angle couttined by the refnctod ray 



■ 



*M 



964 



MAGAZINE OF SCIENCE. 



•ful the Mme perpendioolar t bat ^thU ratio varies 
•rith the refractloK mediuiu. The tlen»cr tbe me- 
(Jiunt, the more the my is bent. The barometer 
fihows. that the density of the atmosphere decreases 
af the height above the earth increates. Direct 
ex|it-rimenta ;trove. thai the refractive power of the 
air incrcusec with its denaity. It foliowa, therefore, 
that if the tonnperaturc be antforcn, the refractive 
power of the air is greatest at the esrth'i surface 
and difuiniahea upwards. 

A ray of light from a celestial object fatliag ob* 
liquely on this variable atmosphere, instead of being 
refracted at onco from ita coursr, is gradually more 
and more bent during its passage through it, ao a« 
to move in a vertical curved line, in the same man- 
ner ai if the atmoflphere consisted of an infiDite 
number of strata of difTcrent deoaities. The object 
ii seen in the direction of a tangent to that part of 
the cur^e which meeta the eye, consequently the 
apparent altitude of the heavenly bodies is always 
greater than their true altitude. Owing to this 
circumstance, the stars arc seen above the horizon 
after they are set, and the day is lengthened from a 
part of the sun being visible, though he realty is 
behind the roTundity of the earth. It would be 
easy to determine the direction of a ray of light 
tlirough the atmosjiherc, if the law of the density 
were known ; bat as this law is perpetually varying 
with the temperature, the case is very complicated. 
When rays pass perpendicularly from one medium 
into another, they are not bent; and experience 
shovra, that in the same surface, though tbe sines 
of the angles of incidence and refraction retain the 
same rotio, the refraction increases with tbe ob- 
Uqaity of Incidence. Hence it appears, that tbe 
refraction is greatest at the horizon, and at tbe 
xenith there is none. But it ts proved that at all 
heights above ten degrees, refraction varies nearly 
as the tangent of tbe angular distance of the object 
ft-om tbe zenith, end wholly depends upon tbe 
hcif^hts of the barometer and thermometer. For 
the quantity of refraction at the same distance from 
the xenith, varies nearly as the height of the baro- 
meter, the temperature being constant ; and the ef- 
fect of the variation of temperature is to diminish 
the quantity of refraction by about its 480th part 
for every degree in tho rise of Fahrenheit's thermo- 
meter. Not much reliance can be placed on celes- 
tial ohscrvutJons within less than ten or twelve de- 
grees of the horizon, on socouot of irregular varia- 
tioDS in the density of the air near the surface of 
the earth, which arc t^omrlimes the cause of very 
ainguiar pbcnomeDii. The humidity of the air pro- 
daces no sensible effect on its refractive power. 

Bodies, whether luminous or not, are only visible 
by the rays which proceed from them. As the rays 
must pass through strata of different densities in 
coming to us, it loUows that, with the exception of 
stars in tbe senith, no object either in or beyond 
our atmospbere is seen in its true plsce. But the 
deviation is so small in ordinary cases, that it causes 
illo inconvenience, though in astronomical and tri- 
momctrical observations due allowance must be 
lade for tbe effects of rcfmction. Dr. Bradley's 
Lbles of refraction were formed by observing the 
amitb distances of the sun at his greatest declina- 
tiona, and the seoilh diataooes of the pole-star above 
and below the pole. The sum of these fonr quan- 
titles is equal to 16<f , diminished by the sum of the 
four refractions, whence the sum of the four refrmc- 



tioQB was obtained : ind from the law of Ibe urn 

tiou uf refniclion determined by theory, be aasigiifif 
the qunntity due to each altitude. Tbe mean hori- 
zontal refraction is about 35' ti", and at tha bcigil 
of forty-five degrees it is :iR"-3G. Tbe eftet of 
refraction upon the same star above and bdowtlis 
pole was noticed by Alhozen, a Saracen astrooosur 
of Spain, in the ninth century, bnt its existence vii 
known to Ptolemy in the second, though be m 
ignorant of its quantity. 

The refraction of a terrestrial object is estimlal 
differently from that of a celestial body. It is wm 
sured by tbe angle contained between the taiv|Ril 
to the curvilineul path of tbe ray. where it ourfl 
the eye, and the straight line joining the eye ud 
the object. Near tbe earth's surface, the pstk d 
tbe ray may be supposed to be circular ; and iht 
angle at the centre of the earth corresponding ts 
this path is called the horizontal angle. Tbe qoii* 
lity of tcrrciitrial refiraction is obtained, by meuor* 
ing contemporaneoasly the elevation of the topsf s 
moantain abore a point in the plain at its bne,uid 
the depression of that point below the top of Ua 
moantain. Tbe distance between these two ststlimi 
is the chord of the horiiontal angle ; and it itcuf 
to prove that double the refiraction is equal to t^ 
horizontal angle, increased by thediffrreucc betna 
the apparent elevation and the apparent deprasiua. 
Whence it appears that, in the usual slaM of tbs 
atmosphere, the refraction ia about the foulenlk 
port of the horizontal angle. 

CTolectmtmmad.J 



APPARATUS FOR INCREASING THE 
ILLUMINATING POWER OF COAL GAS. 

nV J, W. TATLOU. 

CAKBunBTTao hydrogen it is well Itnown owwirtarty 
all its illuminative power to the t\. 
ture of a certain oily vapour, v) 
during the decomposition of the coal m & 
being aware of this, tt occurred to me, ^ 
gas could be more strongly impregiiat< , 
similar compound, the flame would be increaHd il 
intensity, which I afterwards found to be rhr rw 
The apparatus consists of a brass wt*- 
chamber, attached to the end of the ga» ; 
the burner ; this reservoir msy be in the 
an oil-Hank, msJe air-tight with a aerew 
other means of supplying any highly vol 
turpentine or mineral naphtha, and should 
about half full ; into this reservoir the gas 
osoends a little above the surface of the oil ; t 
small jet pipe of gas regulated by a sto[ 
branched off below thin chamber, so as to 
sufficient evaporation of the oil to unite «itfa 
gas in the flask receiver : the whole is, of courss, 
surmounted with tbe usual burner and Ismpglssi- 
By employing this apparatus for burning coal ^ 
the intensity of the flame will be very coosidenUf^ 
augmented, consequently the same degree of 
may be obtained with a far less coasumptiou 
a point wtiich 1 consider of some tmpoi 
may also be employed for burning those 
gas, by tlie decomposition of several of the sothtv 
cites, bituminous earths, woods, \c., whit-h wtwli 
not he otherwise employed with any advsata^ tot 
the purpose of illumination. The apparatos mlftt 
be manufaetarcd at a very trifling cost, being vsiy 
compact and neat in appearance. — CMemui. 



LoXAOir.— PUnlod bv D. FoAMCia. 6. Wbilt Hors« Lnoe. Milt End.— PubUihed by W. Bbittjjm. 1 1 . Paistawla Rsa 
£(Lwbu^, J, MSKSIBS.— Glaasow, D. Bkicb aod J. BASKas.— Ltwrpool, G, Paiui-. 



t 




THE 



MAGAZINE OF SCIENCE 



^nH School of ^rtg. 




IMPREGNATING WATER WITH CARBONIC ACID GAS. 




WALLACES EIDOGRAPH. 



TOt. Ml. — NO. XXZIV. 



266 



MAGAZINE OP SCIENCE. 



IMPREGNATING WATER WITH CARBONIC 

ACID Gas, 
Wb hare already, in Volume 11, giTeti aereral con- 
trivances for this purpoAc aa naed among ua ; we 
give the pment as the French method of Hcconi' 
plishint^ the lamc purpow;. A mere description 
and reference to ibo apparatus will be all that is 
aa£Bcient to render it intelligible. The tno bottles 
A and A. »een on the sides of the apparatos, con- 
Uin rbalk and oil of vitriol. Tbese bodies, u is 
W£tl known, act chrmically upon each other. The 
chalk, which is a carbonnte of lime, hecomea de- 
nompaied. parts with Ita carbonic acid, and its lime 
unites with the sulphuric actd, forming a sulphate 
of lime; the cmrbonii: acid being gaseous, rises and 
remains in the upper part of the bottle, but as an 
infiniltly jcreater quantity is libemtfd than can be 
contained in the bottle, it passes off through a tube 
B, and from that into a second tube D. and alon; 
it into a second bottle E, which ia partly filled 
with water. The gsa being aoluble in water is 
rapidly absorbed by it in this rcsset, until the water 
bfcomea charged with the gas, that is, until it can 
take up no more ; when thii la the case, it, instead 
of being absorbed, paiaea up the second pipe D 
into the lower Te»»el E. The same thing again 
oooora here as in the former veasel, and when tb« 
water in thia lower vessel is in like manner charged, 
the gas will proceed onwards by the third tube D 
into the bottle P, charging thia also; tinalljr it passes 
along the pipe G, btneatb water in the basin H, into 
the air-jnr I, whence it may be removed for use aa 
collected. The reason there are several jara ia, that 
the g«s before it can reach I must paas through the 
water of three vessels, and it becomes thereby very 
pure and cool. The apparatua is to be considered 
double, one side of the cut corresponding to the 
other. Also there are three safety tubes attached 
to vnrious parts, marked C C J ; these are bent 
tithes of glass, having a few drops of mercury poured 
Into them to prevent the pasanKC of air inwards; their 
use ia to prevent bursting of »ny part of the appa< 
ratuB by too great prea&ure of the gaa arising from 
its rapid formation. 

WALLACE'S EIDOGRAPH. 

It is a fact well known, thit artists of yarious 
descriptions, who have frecjuent occasion to imitate 
original designs, have long felt Che want of con- 
venient mathematical instruments, by which a copy 
majr be made with neatness nnd expedition, that 
shall have any given proportion to the original. 
The pantograph is the only instrumeot that baa 
been hitherto employed ; but although correct and 
plausible in theory, in practice it is found to be so 
very imperfect, that the artist hardly ever thinks of 
making use of it. 

A consideration of the essential service that would 
be rendered to the graphic art, by a copying in- 
strument, which should be at once aimple to its 
theory, and easy in its application, induced Mr. 
>\'allsce, Professor of Mathematics, at Edinburgh, 
to torn bis attention to the subject ; and some years 
■go he produced a model of a copying instrument, 
which he dcnomlnflted an ridograph. The instru- 
ment, and its application to the copying of a very 
great variety of subjects, having been shown to en- 
gineers, engravers, and other competent judges in 
London and in Edinburgh, their opinion of its 
Qtility has been such as to leave no doubt of its 
compfclely fulfilling the views of the inventor. 



iscaiT 

i 



The InatmmeDt la represented in Ptg. 2. 
beam A B, which is made of mAbogany, slides 
ward and forward in a socket C : (he sot-krt tunu 
on a vertical axis, supported by the fulcrum D 
which stands on a table. There is « slit tn thi 
beam, through which the axis of the aocket pasafs, 
so that when the beam slides in the socket, apor- 
tioo of it paaaea oa each side of the aais. TlKfr 
are two equal wheels £ E below the beam, whiti 
turn on sies that paaa through pipes filed at A B. 
near its extremities; and a steel chain paaa«s omr 
the wheels as a band, by which a motion of roolki 
may be communicated from the one to the otkcr. 
There are two arma F F. which alide in sockfH 
along the lower faca of the wheels, just nnder char 
centres : at the extremity G of one arm, there is S 
metal tracer, with a handle attached to It. by wbift 
ita pointa may be carried over the lines in sny 
deaign ; and at H, the extremity of the other artn. 
there is a black-lead pencil fiied In a metal rube, 
which is ground to fit so exactly into a pipe so n 
just to slide up or down. In using the instrumraE, 
the pencil in its tube Is raised by a thread wblck 
paases over a pulley, and it deacenda again bf) a 
weight with which it is loaded. 

From the perfect equslity of the wheels, it Is 
(u see, that if the arms attached to them be 
parallel in any one position, they will retain 
paralleUsm, although one of the wheels, and 
quently both, be turned on their centres. Sap* 
posing, now, that B C and A C, the porta into vfab^ 
the axis is divided at the centre, have any propo^ 
tion whatever to each other, if the distancoa of thi 
tracing point G, and pencil point H. from the ein* 
trea of their wheels have the very aame proportBOOi 
then it follows from the elemeuta of geometry. tbU 
the tracing point G, the centre C, sod the pcocfl 
point H, will he in a straight line ; and further, that 
C G, and C H, the diatance of these points froa 
the centre, will have to each other the constant pro- 
portion of C B to C A, or of EG to AH. Soch 
being the geometrical property of the eidogrsph, If 
any subject to be copied be fixed to the table oa 
which the instrument stands, and the tracing prat 
be carried over every line of the design, the pcaefl 
point will trace a eopy in all respecta aimilar to the 
original. To facilitate the adjustment of tbe 'v> 
Birument, so that the copy may have any gtvn 
ratio to the original, there are scales of equal potM 
on the beam and the two arms. By these aut 
niers, both halves of the beam, and 
on the arn:s, are each divided into one 
equal partti, and, at certain intervals, con 
numbers are marked on them. By 
scales, when any ratio is assigned, tbe adji 
is made without the leaat difficulty. 

To avoid any derangement by the chain si 
on the wheels, there are clamps at K and K. 
hold it fast to the wheels at points where it 
quits them. They are alackeueU when the 
meat ia adjusted. 



ALLOYS OF STEEL WITH SlLVl 
BKSinKs the various processea that bave 
adopted ostensibly with the destgo of improrii 
quuhty of pure steel, an almost equal i 
attempts hnve been made to alloy it with 
stances, with which, really or in preteooe, 
been found chemically to combine. These 
have given rise to a variety of s|Hrctous appetUtioof, 
at the best hormkssi wbea applied to mere sof** 



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MAGA2INE OF SCIENCE. 



267 



Ike article profccsrdly mtnufutitred from 
■teel, (he re«i excellence of which, if it 
;tiie cummon reliiier knuws must depend 

EDD hiA old-faabiUDed operaliona Bkilfully 
Two eminent chemisCi make ind pub- 
• of exprrtinriUti, by which it ii demon- 
Mil a sm&ll portion of Tirioiu of the prc- 
al« might be mixed, by fmion, with the 
lOf ttrel ; the idea of turning the di»coTerj 
tl aceoatit is promptly cauj^bti and tilver 
log the advuntagr of eupbauy and nuvelty, 
A pnptilxr denomination in the mnrkrt. 
Hre IB come chance of tbfa manufacture 
Kttdcred aa new-fangled, and diversity and 
Idd being the body and iipirit of buainesa, 
jector tumi him to antiquity : every 
d in cutlery hiring heard of the famous 
res that, while they bent like a switch, 
atern a tempter that they would them- 
tfaroagh ordinnry irona ; m>, witli tuler. 
tut« at least, we are greeted with ibe 
t of DamascvM tteel. Silver, howcTer, 
idient within the reach of every manufac- 
chooses to put it into hia melting pot ; 
cus btriii^ a somewhat equivocal epithet, 
iplyinc rather to a mode than a matcriul 
' ing ; a third party procures from 
Bw lumps of (be celebrated Inttinn wotitz, 
which not many peraoos have seen, and 
tboroagbly onderslwid, and under these 
forth PtTuman »tetl. Each of these 
Diy be of acknowledged goodnesi and 
but at all eventa they most alike be con- 
Uie common credit of an earthly origin ; 
jpwever, with those ferruginous masses 
ji, at different times, fallen from the clouds, 
i policy unite to favor the notion that iron 
ether, and hardened in the north wind, 
I, like Homer's horse* begotten of the 
t, be of excellent temper ; accordingly, 
Ifpe/ hu been among the discoveries which 
pcd Che approbation of the public We 
|| the liberty to introduce, thus plsyfnlly. 
Innations of factitious steel, which, when 
as superior to pure steel, for fine 
pneral, deserve to be treated in no graver 
connected, however, with metallurgic 
t, the processes developing those pecu. 
r elementary chemical combination, or 
tl structure, upon which the obvious 
Rica of the sbove-named steels are aa- 
depend. are far from being uninteresting 
torimentalist. 

ta to combine iron with silver hiTe at 

been made. The experiments of s 

iat, M. Guylnn, as publiahed in the 

de Chimie," were deemed so satisfactory 

tor, tlist he concludes hia detail in these 

Thus the iron was here alloyed with the 

in greater rjuantity than the ailier with 

^ Iron can, therefore, no longer be said to 

Dtx with lilver ; it must, on the contrary, 

Hedged that those two metals brought into 

Ion, contract an actual chemical union ; 

I cooling, the UeAvieit, and, at the same 

most fusible metal, separates for the 

pvt ; that uotwilhstanding each of tlie two 

iHins a portion of the other, ns is the case 

liquation ; that the part which remains is 

|)ly mixed or interlaid, but chemically 

lastly, that the alloy in these proportions 

uliar properties, particularly a degree 




of hardness that may render it extremely useful for 
various purposes." 

A few years ago, Messrs. Stodart sod Faraday 
made a series of experiments on the alloys of iron 
and steel at the laboratory of the Royal Institution, 
the reanlu of which are subsequently published in 
the " Journal of Arts and Sciences.*' From the 
account referred to it appears, that not only silver, 
but platinum, rhodium, gold, nickel, copper, and 
even tin, have an affinity for steel sufficiently strong 
to make them combine chemicatly according to the 
import of this notice, though only ntfchanicaHy in 
the opmion of eome persons. With respect to the 
alloy of silver, there are. according to the testimony 
of the uperimeotalists mentioned above, some very 
curious circumstances attending it. If steel and 
silver be krpt in fusion together for a length of time, 
an alloy is obtained, which appears to be very ^ler- 
feet white the metiila are in a fluid state ; but on 
solidifying and cooling, globules of pure silver are 
expressed from the mass, and appear on the surface 
of the butttiD. If an alloy of this kind be forged 
into a bor, snd then dissected by the action of 
dilute sulphuric acid, the silver appears, not in 
cambinaiion with the steel, but in threads through- 
out the ma£s, m that the whole has the appearance 
of a bundle of ftbres of silver and steel, as if they 
had brrn united by welding. The appearance of 
these silver fibres is very beautiful ; they are some- 
times one-eighth of an inch in length, and suggest 
the idea of giving mechanical toughness to steel, 
where a very perfect edge may not be required. 

At other times, when silver and steel have beea 
very long in a state of perfect fusion, the sides of 
the crucible, and frequently tbe top also, are covered 
with a fine and beautiful dew of minute globules of 
nilver ; this effect can be produced st pleasure. At 
Arst the oi>erators were unsuccessful in detecting, 
by means of chemical tests, the presence of silver 
in the metallic button ; and coosidering tbe steel to 
be uniformly improved, they were disposed to at- 
tribute its excellence to tbe effect of the silver, or 
to a quantity too small to be tested. By subse- 
quent cxpL'Hments, however, they were able to de- 
terl the silver, even to less than one part in five 
hundred. 

" In making tlie sliver alloys, tbe proportion first 
tried was 1 silver to 160 steel; the resulting but- 
ton! were uniformly st^l snd silver in fibres, tbe 
silver being likewise given out in globules during 
solidifying, and adhering to the aurfaee of the fuatd 
button ; some of these, when forged, gave out mure 
globules of silver. In this state of mechanical 
mixture the little bars, when exposed to s moist 
atmosphere, evidently produced voltaic action ; and 
to this we are disposed to sttribute the rapid de- 
struction of the metal by oxydation ; ao such de- 
structive action tuking place wlien the two metals 
are chemically combined. These results indicated 
the necessity of diminiihing tbe quantity of silver, 
and 1 silver to 200 uteri was tried. Here, again, 
were fibres and globules in abmidsnee; with 1 to 
300 the fibres diminished, but still were present ; 
they were detected even when tbe proportion of 1 
to 400 wu used. The saccesxful experiment re- 
mains to be named. When 1 of eilver to oOO steel 
were properly fused, a very perfect button was pro- 
duced ; DO silver appeared on its surface ; when 
forged and dissected hy an acid, no fibres were seen, 
allbough exsmiued by a high magnifying power. 
The specimen forged remarkably well, alUiough 
very hard ; it bad, in every rcipect, the most favor- 



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MAGAZINE OF SCIENCE. 



able ippetnnoe. By ■ delicits tcit emy part of 
the bar gave liUer. Thin sllojr i> decidedly superior 
to tbe very best steel ; and this rjccellence la un- 
que*ltonablr owing to combination «ith a minute 
portion of tilvrr. It has been repeatedly made, and 
always with equal lacceii. Varioni cotcing tooli 
baTC been made from it of tbe best qaality. This 
alloy is, perhaps, only iofertar to that of steel with 
rhodiam ; and it nisy b« procared at a imall ex- 
p«nfle ; the valae of silver, where the proportion is 
so small, is not worth naming ; it will probably be 
■ppUed to many important purposes in ibe arts.'* 



STEAM AND THE ST£AM ENGINE. 

iltnumed/min pagg t4i } 
Tb* properties of steam are now so generally 
known, that it scema almost impossible that man- 
kind should have remained ig:norant of its power 
for so many ages, particularly upon tbe reflection 
that thry were, even from tbe first period of civitiza- 
tion. acqaainted with many of the uses of (ire, in 
smelling and working metals, cooking victuais, 
heat-ing water for baths, and other purposes, some of 
which must of necessity have tanght them that water 
rises into steam by heat, and condenaea again by 
cold. It is even said thst Pspin, the real inventor 
of the steam eni;itie. bad hii nttrntiuii drawn tuthe 
power ot vapor by observing tbe lid of hii tea kettle 
Aj off. Be this anecdote true or not, it is certain 
thai steam, as a motive power, applicable to useful 
purposes, was not previoosly thought of; still this 
nrt is to be taken with some little reservation, as it 
ia known that two or three philoHophiral tova, acting 
by steam, were prfvioualy known, and others acting 
by the expansive force of con5ned air were atill 
more cotiimon ; and in one inetiince this expansive 
force was mnde subservient to impose upon the re- 
ligious credulity of a people. We allude, of courie, 
to Hero's altar, a contrivance of conKiderablc in- 
genuity, and which may be tbos described : — 




A aqnare pedestal, like an altar in shape, made air 
tight and hollow, the top of it being of thin metal, 
wai eosoecied i^iih aaother and a wider vcssd at 



die foot ; tbrr* being s bote between tbe twt» 
The lower vemsel was nearly filled with oil. Tbe figure 
of a priest stood by the side of the altar, with bia 
eitended, and buldiog in bis tiund a v«ae ; a 
pipe was concealed within the body of ibfi flfWS* 
and extended from the bottom o( the vaaw (aaBs> 
municatiog with it) along tbe arm, dnwn the body, 
and into the lower vessel, where it dipped benesih 
the surface of the oil. When a Are waa lighttd 
upon the altar, tbe air witliin it was rarelicd, snil 
consequently pressed upon the surface of the oil, 
driving it up tbe lube, and not merely frlling ihs 
vase, but even running over on to the fire, aodtbsfK 
fore increasing tbe Barnes. This taereMe of (^ 
fire produced of neceaaiiy a farther rareAeatim «f 
the air, and a fresh supply of oil, unci! the whole 
contents of thennder ve*aelwereeihau>ted,or nttet 
until the air coald get into tbe pipe bdongisgts 
tbe image. 

Thst which suggested tbe following appanta 
was, most probably, the atalue of Memnon, rt< 
corded to have emitted sonnds, which were ascribed 
to the interposition of aaper- human agency, sai<iin 
after times to have been produced by pojsor ramf 
Jrom tcater, concealed in a cavity of Out sUIb«. 
being made to pass through a tobe. having a crnsli 
oi-ifiee frtshluned in a manner similar to that of lbs 
pipe of sn organ. As long a* the fluid wm haitsA 
by the rnyaof the sun, mysterioui sounds were beitd 
by tbe assembled worshippers, which died gradttsDy 
away aa the solar influence waa withdrawn froai lla 
gigantic idol. This explanation is ascribed to Hvt 
himself, and Is to be found in his " Ptieaaiatia.*' 
The subject has exercised the ingenuity of otfteT 
writrra. Among the moderns, ^^ulomon De Csa 
and Kircher, Pgrts, Branca. Cardan, and ottwfl. 
That the above could not have been the niaie of Aft 
sounding of Memnon's statue most be evidenCt^ 
catue the sun's heat wss nut sufficient to rattr tbe 
water in vapor, or in other words Co raioe it to a 
height of 212' of heat j but as in tba eaae of Hero's 
altar, the rarefied air rushing out migbt bair pr»> 
duced a noise, it passing through a properly-COi* 
alructed orifice. 

Tried by the high standard of even modem il* 
tainment, several of the machines invented by HfTV 
may be compared with the most nseftil, or the moA 
ingenious, of those which have been appealed to si 
proud monuments, placing oar own age at sn Vn- 
mense distance beyond every other in n> 
invention. The fountain for raising w.*' 
compre-ssion of atr remains as he left it. As ism w 
a close cunnectiou with several machines which sis 
to follow, we briefly describe it. 

One figure shows the exlemal appearanor, tk 
other the internal section. There are three veasils, 
two of them inclosed; as C D. and one of them opia 
at the top, as P. A pipe G extends from F, throng 
C into D, where it reaches nearly to the battms 
A second pipe H paa&es from nearly the top of C 
through tbe bottom of C, and into tbe top of n< 
A third pipe proceeds into the vessel C, and o^ 
wards Into the air. Wben water ts peiurrd latot 
it passes down the pipe G. supplying D with man 
water, tbe air within it is driven up the pipe H iflM 
C. The condensation that here takes place drr*a* 
the water up the centre pipe, from the top of ah if fc 
it issues in a jet. The effect here, proceeding ssh 
docs from the sole pressure of the short ooloae ' 
water In G, could have been but trilliD^ ; batwfca 
Hero employed the force of fire, aa in bis aluft 
then it became aa tnstrumeut whieb. tkoufli p"* 



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MAGAZINE OF SCIENCE. 



369 



il fa iUelf. yet wu acted upon by • 

yie of being used to any extrat, u it has 

it HnH if its applicstioni it ■ former prrind 

litirs ratlirr tlian useful inatrumcnti, stilt 

a roundation upon which Co rrst the 

and eiperiineuts of later philotopbers. 




thirteen machines which operate hj 

of heat on air and water. In t«ro the 

I temple are opened and shut hy means of 

Etion of air ; in another, water or wine id 

tt>e same incani ; in onoiber this is com- 

Ibe hiising^ of a dragon ; and a rotatory 

in another imparted to a smiilt stage, on 

mata are placed. In some of these, from 

notion of the apparatus, ateam of low 

Ould be produced, and assist in the action. 

^ont it is not quite obnous that Hero 

0a of the distinction between the heated 

vapor, or rather he roiisidered that the 

td ita powpr to the htatfd tttr with which 

ibioed or mixed. The method of giving 

a veaael by means of steam, deserves at- 

I it ia the origin of all the nofDcrona 

wbiiih haTeBince been invented. Three of 

rumentf were described in the " Magazine 

' (Vol. n. page 308.) the first of 

of tboae given by Hero ; we will there- 

t-deacribe it, but rather ahuw another kind 

id at a later period, but upon precibely the 




A to be a hollow ring, with two bent 
turning in contrary directions, a metal 
Im! aorosa the hngicrves at the same time 
en K, and to support it on a central 
rot C, round which it may rotate. Tbu 



rinic ti Doirly filled with water. B ia a ring.ahaped 
diah ot troagh. llUcd with tow and tallow, and used 
instead of a fire, to heat the ring above : D is a foot- 
board to support the whole. When the wiitcr in A 
is heated, the steam will nish oat of the jett, and 
by its action upon the air, or rather by the counter 
action of the air upon it, will rotate rapidly. 

These attempts at employing steam as a me- 
chanical power are described, without even a hint 
at their extension to any nsofal pnrpo«e. Thii can 
detract but little from the merit of Hero, a sagacity 
little short of prescience could aloue have enabled 
him to anticipate the grandeur of that creation that 
was to arise from these beautiful, bat comparatively 
iniignificaat beginnings. 

fTo be amtismtd.} 



STRENGTH OF MATERIALS. 
f Resuvtftt frvtn fxige 263, and comtudcd. ) 
Thk degree in which the itrength of jitrnctarft is 
dependent on the form and position of their partly 
will be illustrated by considering the two cases of 
longitudinal and transverse compression ; and ths 
rule for giving strength will be found to be, to 
cause the force tending to destroy, to act, as equally 
as may be, on the whole resisting mass, at the same 
time, and vrith as little mechanical advantage as 
poflaible. In longitudinal eomprettion, as produced 
by a body on the top of a pillar, the weight, while 
the support remuna straight, can only dentroy tba 
support by crushing it in opposition to the repol- 
aion and im[>enetrRbtUty of alt ita atoms. Hence a 
very small piUar, if kept perfectly straight, anp- 
ports a very great weight ; but a pillar originally 
crooked, or beginning to bend, resists with only 
part of its strength ; for the whole weight above ia 
supported on the atoms of the concave side only, 
which are therefore in greater danger of being over* 
pressed and crushed, while those on the convex 
aide, aeparated from their natural helpmates, are 
in the opposite danger of being torn asunder. The 
atomft near the centre, in such a case, are almoec 
neutral, and might be aburnt without the strength 
of the pillar being much lessened. Vong pillara or 
supports are weaker than short ones, because they 
are more easily bent ; and they are more easily bent 
becaufie a very inconoiderable, and therefore eaiily 
affected, yielding between each two of many atorat, 
makes a conaiderable bend in the whole ; white iu 
a very abort pillar, there can be no bending with- 
out a great change in the relation of proximate 
atoms, and such as can be effected only by great 
force. The weight or force bending any pillar may 
be considered aa acting at the end of a long lever, 
reaching from the end of the pillar to ita centre, 
agaia»t the atrength resisting at a short lever from 
the aide to the centre- The utrength, therefore, haa 
relation to the difference between these. Shortness, 
ihcn, or any stay or projection at the side of tba 
pillnr, which, by making the rraisling Icvrr longer, 
oppneea bending, really increases the strength of a 
pillar. A culumn with ridgea projecting from it la, 
on thla account, stronger than one that is perfectly 
smocjth. A hollow tube of metal ia itronger than 
the aarne quantity of metal in a solid rod, because 
its aubstance, standing further from the centre, re< 
sista with a longer lever. Hence pillars of cast- 
iron are generally made hollow, that they may have 
mrength with as little metal as possible. In the 
moat perfect weighing-bcami for delicate purpoaes, 
that there may be the Icaal possible weight with the 




270 



MAGAZINE OF SCI£NC£. 



required atrength. the Arms, inat«ad of beinp of 
solid m«Cal, are boUaw coDtrs, iu which the metAl is 
not mnch thicker than writing pvper. Muta and 
jftrda for abipt have been made hoUow, in accord- 
■Dce with the same principle. In nature's workB| 
we have to admire numerous Ulustrationfl of the 
Bame cIoas. The Bt«ms of many vcgeUblKs. instead 
of being round externally, are ribbed or angular and 
fluted, that they may have strenf^th to resist bend- 
ing. They are hallow, also, as in cornstalks, the 
elder, the bamboo of tropical ctimatea, &c., thereby 
combining lightness with their strength. A person 
who visits the countries where the bamboo growa, 
cannot bat admire the almost cndlrss uses to which 
its strai^htncss, lightness and hoUowness, make It 
applicable among the inhabitants. Being found of 
all sizes, it h%i merely to be rut into pieces of tbe 
lengths required for any purpose ; and nature has 
already been the turner, tnd the polisher, and the 
borer, fee. In many of the Eaiitern islands, bamboo 
ii tbe chief material of tbe ordinary dwellings, and 
of lliefiiniitureT — the fanciful chairs, couches, beds, 
&c. Flutes and other wind instruments there are 
merely pieces of the reed, with holes bored at the 
rc(|uiaite distances. Conduits for water are pipes of 
bamboo ; bottles and casks for preserving liquids 
are single joints of larger bambfw, with their par- 
^tions remaiuing ; and bamboo, split into threads, 
ia twisud into rope. ficc. From tbe antmal king- 
dom* slso, we have illustrations of oar prt'srnt sub- 
ject — the hollow stiffness of the quilJs of birds i 
the hollow bones of birds; the bones of animals 
generally, struug and hard, aud often angular ex- 
ternally, with light cellular texture within. Sec. — 
TYantvergf prctMvre. \Vhen a horizontal beam ia 
supported at its extremities, its weight bends it 
dawn more or less in the middle, the particles on 
the upper side being compressed, while the parts 
t)elow are distended ; and the bending and tendency 
to break ire greater, according as the beam is longer 
and its thickness or depth is less. Tbe danger uf 
breaking, in a beam so situsteil, is judged of hy 
considering the destroying force as acting by the 
long lever reaching frum the end of t}ie beam to tbe 
centre, aud the reststing force or strength as ai:ting 
only by tbe short lever from the side to the centre, 
while only a little of the substance of tbe beam on 
the under side is allowed to resist at all. This last 
cirottmslaoce is so remarkable, that the scratch of a 
pin on the under side of a plank resting as here 
supposed, will sometimes suffice to begin the frac- 
ture. Because the resisting lever is small in pro- 
portion ss the beam is thinner, a plank bends and 
breaks more readily than a beam, and a beam rest- 
ing on its edge bears a grcatrr weight than if resting 
on iu side. Where a single beam cannot be found 
deep enough to have the strength required iu any 
{>Articular case — as for supporting the roof of a 
house — scvrral beams are juincd together, and io 
great variety of ways, as is seen in houae-rafurs, 
&c., which, although consisting of three or more 
pieces, may be considered as one very broad benrn, 
with those parts cut out which do not contnbule 
much to the strength. The arcAef/ybrm bears trans- 
verse pressure so odmirubly, because, by means of 
it, the force that would destroy, is made to compress 
all the atoms or parts at once, sod neurly in the 
same degree. The atoms on the under side of an 
arch, resting aprinst immovable abutments, must be 
compressed about as much as thoie on the upper 
side, and cannot therefore be torn or overcome 
separately. Tht whole substiiace of the arch there- 



fore, mists, almost like tliatof a atraigltl pillar under 
a weight, and is nearly as slrong. To be able to 
adapt the curve to the size of an arch, snd to tb« 
nature of the material, requires in the arcbit£cta 
perfect acquaintance with measures, 4te. An rrrur 
which bos been frequently committed by bridgN 
builders is, the neglecting to consider sufficiently (te 
efTect of the horizontal thruat of tlx arcb on its piefi. 
Each arch is an engine of oblique force, poshing Ikii 
pier away from it. In some instances, one arcb of 
a bridge falling, hss allowed the adjoining piers W 
.be pushed down towards it, by the throat, no Ioii|tf 
balanced, of the arches beyond, and the whole 
structure has given way at once, like a child'a bridft 
built of cords. It is not known at what time tk 
arch was invented, but it was in comparatively bi> 
dern times. The hint may have been taken froa 
nature; for there are ineunces in alpine conntrin^ 
of natural arches, where rocks hsve fiillen bet««cfi 
rocks, and have there been atrritted and tuspendad 
or where burrowing water has at last formed a ^ 
passage under masses of rock, which remain 
Isnoed, among themselves, as an arch above 
stream. Nothing can surpass the strength 
beauty of some modem stone bridge* — ^000^ 
instance, which span the Thames u it 
London. Iron bridges have been madewiA 
twice as large as those of stone, th« material 
more tenacious, and calculated to form • 
whole. Tliat of three fine arches, between 
of London and Southwark, ia a nobi 
and, compared with the bridges of half a 
ago, it appears almost a fairy structure of 
and grace. Tbe great domes of churches, 
of St. Peter's in Rome and St. Paul's in 
have strength on the same principle as simple 
7*bey are, in general, strongly bound at tbe boltov 
with chains aud iron bars, to counteract tbe boft- 
zoiitul thrust of the tuperstmcture. Tbe GolMC^ 
arch is a pointed arch, and is calculated to bear (It 
chief weight on its summit or key-stone. Its o^ 
therefore, is not properly to span nvera as s bridgs^ 
but to enter into the composition of varied pisoa 
of architecture. With what effect it does this, is 
seen in the truly sublime Gothic ttracturr ^ w\.\A 
adorn so many parts of Europe. The 
are instances, in smaller bodies, of otT' 
tained by the arched form :— A thin wstchgUn 
bears a very hard push ; a dished or arched wbad 
for a carringe is many times stronger to raaitt id 
kinds of shocks than 1 perfectly flat wheel ; a hfl 
CBsk may fall with impunity, where a strong squan 
box would be daslied to pieces ; a very thin globi* 
Ur flask or glass, corked and sent down may 
fathoms into the sea, will resist tbe pressure n 
water around it. where a square bottle, with ilifas 
of almost any thickness, would be oruibcd to 
We hove an illustration, from tbe laiiDid 
the arched form giving strength, in the cran 
skull, aud psrtirulArly in tbe skull of man, whit^ 
the largest in proportion to its thickness: the braia 
required the most perfect security, uid by tks 
srched form of the skull, this baa beni (^taincJ 
with little weight. The common egg-shrll Ii 
another f-Ximple of tbe ssme claaa r what hard 
blows of tht? spoon or knife arc often required t« 
penetrate this wonderful defence provided for 
dormant life t The wcaknfs« of a fiimilur sul 
which has not the arched form, ii seen in 
from a piece of freestone, which so readily ci 
between the fingers. To determine, for 
cases the best forms of beams and jotsta, add si 



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MAGAZINE OF SCIENCE. 



271 



M) he., I« the basinets of strict calcu- 
Wloiiffl, therefore, to lutithematitia, or 
t nieasares. It was a heautiful pro- 
I kind, which Mr. Smrnton Bolvrd so 
he conatruction of the fir-famcd Edily- 



r 

FRRSCO PAINTING, 
f Art, applied by the Italian artists to 
cuted in diatemper or siie colon. On 
>r the arts in Kiirope, it became ens- 
cornte the outsides of churches, palaces, 
id coavents, with historical picturvs ; 
twcreeiposed to Che impressions of the 

the term ai fretco wu applied to the 
Hinting itsetf. The decorations and 
If modem theatres are likefrise executed 
*. or rreflco. bat there are certain pecu- 
mdin^c the ItJilisn roetliod, which we 
t to describe. The size of the wait to 
t beiof^ aacertatoed by accurate ineasure- 
ihed drawing on paper, railed a cartoun, 
ide, to serre u a model. The artist, 
certain portion of the wall covered over 
Kilt of stucco, or Roman crment, of the 
an inch, or more, and upon this portion 
ff from bis cartoon enough to All the 
), at it was ntcetsary to the success and 

of bis work that the colors should be 
le the stucco was yet damp, no more 
applied at one time than what the artist 
«ritfa convenience in one day. The first 
iperation, after the tracing, was to lay in 
»f color with a large brash, and then to 
t parts by delicately hatching tlicm over 
tof minute strokes, by means of smaller 

riters on fresco painting, different pro- 
tacribed for mixing up and preparing the 

they all agree in stating that the colors 
t native earths or minerals, as lakes and 
ilors will not stand, and that the whites 
' khoald be of wbite chalk, or powdered 
Xmdly, that the vehicle should be a solu- 
al glue, prepared by boiling the skins of 

fislies, such as parings of parchment, 
r, Ace, or from the whites of eggs. One 
indeed, directs that a certain number of 
folks, shells. Ifcc, shoald be well beaten 
Boded in a marble mortar, and that a 
fo of good vinegar (say a gill to six eggs) 
iMlded. and the whole miitnre beat np 
h of fresh twigs cat from a fig-tree. In 
e white and yolks of the eg^ form a sort 
^ and, the vinegar dissolving the earthy 
te shells, renders the vehicle more bind- 
llownesa uf the eggs would not materially 
olors. neither wuuhl the whites be lar- 
ehy, being of chalk, which would not be 

white lead or ceruse were employed, 
g leaves, it is well known that the jnice 
y them is a species of Indian-rubber, or 
—BO elastic gnm, which will render the 
lablo to crack. In this mnnner all the 
» paintings of the churches in Italy have 
ed. The Sistine chapel, Vatican, Grotto 
mesine palace, &c. 

mded, that there are specimens of fresco 
snt uf the time of Constuntine the Great. 
t revive in the sixteenth centnry. The 
Michael Angelo and Raphael shows how 



worthy it ta of the greotest artiaCf. The painter 
cannot seduce the senses by soft tints and tendn^ 
harmony of colors ; be \», tberefore, reduced to 
depend solely on form, character, ezpreosion. If 
oil painting is better suited for nice exprcasions of the 
slightest emotions of the heart, fresco patntiog is tha 
field which the true poet* painter will prefer. What 
can be more sublime than the last judgment of 
Michael AngeU), in the Capella Sinthiaf How rich 
and vast are Raphael's conceptions In thesfdnxeand 
loffifie .' The Germans possess at present the most 
distinguished fresco pointers ; and Cornelius ho* 
established his fame by his grand fresco pictures io 
the Gfyptoihtca, in Munich. Schnorr is also dis- 
tinguished in this line -, and the villa Mastimi, near 
Rome* is a fine monument of contemporary Germaa 
art, as Overbeck, Schnorr, and Peith painted th« 
three rooms in fresco. Fresco painting was long 
disregarded, when all noble and grand concrptiona 
seemed to have 6ed from the art ; and it is only in 
rrreiit times that it has been taken up again, chiefly 
by the Germans. 



MANUFACTURE OP COKE. 
Ox the first introduction of coke, the coals were 
merely piled on a heap, ignited, and, when snffi- 
ctently burnt, the beat was smothered by covering 
tlie pile with dust and sand. Since the matter has 
been better undftretood by practice, and a knowledge 
of chemistry, more perfect and economical methods 
have been adopted : these consist generally in the 
use of dose furnaces or oTeus, mostly contignons to 
the iron works, and under the same mansgement. 
Parkes has described the hemispherical ovens for 
the barntng of coke, which exist in the neighbour, 
hood of ShefSrld ; they are about ten feet wide at 
the base, and two feet at the aperture : the wall of 
brick eighteen inches in thickness. 

" When these ovens are once heated, the work 
goes on night and day without interruption, and 
without any further expense of fuel. It ts con- 
ducted thus : — small refuse coal is thrown in at the 
circular opening at the top, sufficient to 611 the 
oven up to the springing of the arch ; it is then 
levelled with an iron rake, and the doorway on the 
side built up with loose bricks. The beat ac«)uired 
by the oven in the former operation is always auffi* 
cient of itself to light np the new charge, the com- 
bustion of which is accelerated by the atmoipherio 
air thKt rushes in through the joints of the loose 
bricks in the doorway. In two or three hours the 
CDmbostion gets to such a height, that they find it 
ncccxaary to check the influx of the air ; the door- 
way is therefore now plastered up with a mixture of 
wet soil and sand, except the top row of bricks, 
which is Uft unplaatered alt night. Next morning, 
when the charge has been in twenty-four hours, 
this is completrly closed also ; but the chimney re- 
mains open till the flame is gone, which is generally 
quite off in twelve hours mure ; a few loose stones 
are then laid nvcT the aperture, and closely covered 
up with a thick bed of sand or earth. All connee- 
tion with the atmosphere is now cut off, aodio this 
situation the whole remains for twelve honrs to 
complete the operation. The doorway is then 
opened, and the cokes are raked into iron wheel, 
barrows to be carted away. The whole operation 
takes up forty-eight hours, and as soon as the cukes 
are removed, the ovens are again tilted with coal 
for another burning. About two tons of coals are 
put in for each charge, and the cokes produced are 



272 



MAGAZINE OP SCIENCE. 



poaderona, eitremdf lurd. of ■ li(bt gnj color* 

■nd thine with meUllIc lustre. 

•' When coke u required to be more of the niture 
of chflrcoal. the proc«i< ii conducted in a different 
nftnner. Tlie tmall cosl ii tlirown into ■ large re* 
cepUcle, similBr lo ■ baker's oven, preTionalj 
broug^bt to ■ red heat. Here the door ii conituilljr 
open, and the beat of thr otcq ii sufficient to dtui- 
pate all the bitumen of the coaU. the diAenfagemrnt 
of which is prumoted by frequently stirring with 
a long iron rake. The coke from these OTCns, 
though made with the same kind of coal, is rerj 
different from that produced by the former opera- 
tion ; this being intensely black, very poroai, and 
u li^t as pumice stone." Both these descriptions 
tti roke enter into the proce&s of smelting ; the 
former is capable, not only of acquiring an intense 
beat, and lasting a considerable time, but likewise 
of sustaining a great wei)(ht of ore in the furnace 
vithout presently foiling to ashes ; the latter sort 
is more ioHammable, but considerably leaa dnrable. 



MEDICAL RECEIPTS, &c. 

Talc Water. — The sncients bestowed high en- 
comiums on a water, or oil of talc, as a rofmetic. 
We know not in what manner they composed this 
precious coiimetic, but the following imitations have 
Deen given. Take any quantity of talc, divide it 
into Umio«. and calcine it with sulphur. Then 
pound it, and wash it in a quantity of warm water. 
Gently pour off the water, and leave the residue at 
the bottom of the vessel dry. When dry, calcine it 
in a furnace for two hours with a strong fire. Take 
a pound of this catciur.d talc, and reduce it to a 
powder, with two ounces of hydrochlorate of am- 
monia ; put the whule in a glasa bottle, and set it 
In a dsmp place. AU the talc will spontaocoualy 
dissolve, and then pour off the liquor gently, taking 
great care not to disturb it. The liquor is as clear 
and as bright ss a pearl. 

OUqf 7Wc.— Take I port of Venetian talc and 
two parts of calcined btrrai, perfectly pulverize and 
mix these substaacca, put them into a crucible* 
cover it and place it in a furnace. Expose it for 
an hour to a very violent heat, and at the end of 
that time the mixture will become a glsss of a green* 
ish yellow color. Reduce this to powder, then 
mix it with two parts of carbonate of potass, and 
again melt the whole in a crucible. Place the mass 
thus obtained in a cellar, upon an inclined piece of 
glsss. with a vessel underneath it. and in a short 
time the whule will be converted into a liquid, in 
which tlie talc will be perfectly dissolved. 

Tw Water.— k remedy celebrated by Bishop 
Berkeley, is prepared by infusing tar with boiling 
water, which produces a yellow empyreamatic liquid. 

Tayhr't Red £o«/e.— British brandy, tinged 
vritb cochineal and flavored with oU of ori^Rntim. 

Taylor's Remedjf /or DeofneM is an infusion of 
garlic in oil of almoods, colored with slkanet root. 

Tayior't D^entor. — Thin isinglass jelly with a 
little permanent white well mixed in while cooling. 

Terrti-AIetaUinim. — An amalgam of tinfoil and 
qaickailver for filling decayed te-«th. 

TurtingioiCt BaUam is rosde with 3 ounces each 
of aloes, myrrb, balsam of Tolu, bnlsani of Peru, 
and ohbsnum, 9 ounces each of benzoin, and of 
storax, A\ pints of alcohol. Digest in a warm place, 
and add 3 ounces of gum arable in 1^ pint of water. 



ftherH^J 
rsCmo^H 

coldl^H 



Ke/no's Vegetable Symp, according to AM^/ 
compoaed of a solution of bichloride of 
triturated with honey and mucilage. Aceontingt 
Swediaur it contains volatile alkali. Acoordhig 
Sir C. Brodie, it is similar to the following:-— 1^ 
2 ounces of bnrdook root, (young and freafa.) s&etf. 
1 ounce of dandelion root, I ounce of fresh tpear 
mint, 1^ dram each of senna leaves, coriander wit4 
bruised, and fresh liquorice root, and l( pint d 
water ; boil down to 1 pint, strain, and when coU 
add 1 pound of refined sugar, boil to a vymp, sij 
add a small portion of the lolutioo of bkhlondeflf 
mercury . 

Walter** Jeeuit'e Drope. — Take 1 pound oTfta 
gaaiac, 3 drams of bolimm of Peru, 2^ pints of rtr- 
tifird spirit ; make into a tincture. Dose 1 dfsa 
to 2 drams aa an anti-venereal. It Is thessDeis 
the balsam of guaiae, and the anti-venereal eDiir. 

WoMt'M Powder, for gout anil rheumatism, islks 
powdered bulb of colchicuro, with some other 
ders, to disguise it. Mr. Want was the first 
surgeon who discovered the influence of 
on gout, though it was known to the aoctenti 

WartTa Sv^ecting Powder*. — A combinatioa flf 
opium and white hellebore. root. 

Ward't White Droya. — A aolution of bichlwiis 
of mercury with carbonate of ammonia ; or s ^ 
trate of mercury, prepared by dissolviug memfj 
in nitric acid, aud ailding solution of earbooata of 
ammonia. 

Ware*w Golden Om/mm/.— Take 1 oonc* d 
fresh butter, free from salt, I dram of the powdtf 
of nitrated oxide of mercury ; moke an ointmratte 
ophthalmia and ulcers. 

Wamer^a Cordial, — Take 1 ounce of bmisid 
rhubarb, \ ounce of senna, 1 dram of saffroB, 4 
drams of powdered liquorice, 1 pound of poondsd 
raisins, and .1 pints of brandy; digest for foartsM 
days, and filter. 

Webater'g Diet Drink, or Crremsia Anffliemt.-~ 
A decoction of liquorice, guaiac. aanaparilla, ssssfr* 
frss, turmeric, hitter -sweet, betony, and thywtt 
boiled, with or without sugar, to the cooaistenod cf 
syrup. 

Wealphalian Esience qf Wood Smote. — Mset* 
rate together for several weeks, ^ dram of Bsrhs- 
doea tar, 1 dram of liquid burnt sugar. S dranu sack 
of port wine and vinegar, 2 drams of commoo salt, 
and 6 ounces of water. Used for curing hanu. 

WAiteMead'a Eaaence of Mtutard does not oss* 
lain, according to Dr. Paris, a particle of ramtnii 
but is merely balsam of Tolu with reein. Aoowtf* 
tng to Mr, Brande, it u composed of camphor, ail 
of turpentine, and spirit of rosemary, miied witii 
mustard flour. 

Wodroqf. — A native plant, oommon In wombt 
which has s fine odour of hay when dried, but whia 
green is nearly inodorous. Il i* said to be dco^ 
struent. The floweis give a fine flavor to lea ssl 
wines. 

Zanthorylon /V-ffjioewm.— Prickly Ash. 1^ 
bark ia stimulant and stalago^e, and is med is 
rheumatic tooth-ache, and chronic rbeomalisoi, ia 
doses of 10 grains to 1 scruple of the powder; ^ 
4 ounces to U ounces of the decoction cverj fosf 
hours. 

Zingebar. — Presen-ed G inger Root. This !■ 
brought from the East Indies, and ia aliDOst trMS- 
parent. That which is candied at home ia 0pKie> 
It is a good sLimiUant fur the gouty and ocrvooa. 



l.n«90N.— Pnntad hy t). Fuhci*. C. Whits llorst Laoe. Mil* End— Publiibad hy W. BatrrAts. 1 1 , PatoraertM Row 
ComiaunleaUoiu. (which srs aniwarcd Muullily.) to bt addmstd lo ttic Editor. at 37. Coita|t Gr«rt. MUs B ' ~ 



THE 



yiAGAZINE OF SCIENCE 



ana Sdjool of ^xK. 



SATURDAY. XOVeMBRB ST. I<41 




COMBUSTION OF THE DIAMOND. 

Tni eocnbustibtlity of the diamond teems first tn 
b»Te occoiTijci to Newton. In the year 1694, the 
Plorentiufi Academicians verified luB an tic i pat tons, 
■od proved its dritnictihility by Iitst by uitans of 
a burning lens. Tbe produeta of its cotubuslion 
were first examined by Lavuisier in 1772, and sub. 
lequenlly with more prcciiion by Guyton Morvean, 
in 178.S. In 1797, Mr. TonnanC demonstrated the 
tinportaut fact, that wbtrn equal weights of diamond 
and pure rhnrconl were submitted to the actiOQ of 
rvd-hot nitre, the results were in both cases the 
same : aud in IKO?, the combustion of the diamond 
in pore oxygen was founil by Messrs. Allan and 
Prpys to be attended with precisely the same results 
aa the combusUon of pure charcoal. 

AVhen the diamond ia heated in the flame of the 
blow. pipe it soon begios to burn, and the combus- 
tion continues as long as the temperature is suf- 
ficiently high, but it does not produce heat enough, 
during its combinntion with the oiygen of the at- 
mosphere, to maintain its combustion. If, whilst 
thus burning, it be introduced into a jar of pure 
oxygen, the combustion continuts longer, and some- 
times till the whole is coatumed : the best support 
for it, in this expeiiment, is a small loop of ]ila- 
tinam wire, or a very small and thin platinum 
spoon, perforated with mnny lioles; in this it may 
first be intensely heated by the oxygen blow-pipe, 
and whilst burning carefully immersed into a buttle 
of pure oxygen gnv, contniniiig a little lime-water : 
a good cork, through which the wire of the spoon 
passes, should secure the mouth of the battle : it 
will thus go on burnini^ bnlliantly for some time, 
and the formation of carbonic acid be shown by the 
milkiness of the lime-wntrr. 

The combustion of the diamond may be more 
perfectly cfiected by placing it upon a platinum 
capsule in a jar of pure oxygen inverted over mer- 
cury, and throwing upon It the focus of a burning 
lens. Sir H. L>avy, when at Florence, in 1814, 
used for this purpose the same lens which was em- 
ployed iu the first trials on the action of solar beat 
on the diamond, instituted by Cosmo III., Grand 
Duke of Tuscany : be found that the diamond con- 
tinued to bum in the oxygen, af^er being withdrawn 
from the focus, with so brilliant a lii^hl as to be 
visible in the brightest suu»hiuc, aud witli very 
intense heat. 

The Fig., No. l., is another form of apparatus 
which may bo conrenicntly employed for exhibiting 
the results of the combustion of the diamond. It 
consists of a gloss gtube D D, of the capacity of 
about 14U cubicul itichea, furnished with a cap, 
having a large &pert<iro; the stop-cock, which 
screws into this cap, has a jet A rising from it. 
nearly into the centre of t\w. globe ; tliis is dt^tined 
to convey a small stream of hydrogen, or other in- 
flammable gaa. Two wires C C, terminate' at a very 
little distance from each other, just above this jet, 
and are intended to inflame the stream of Itydrogeo 
by electrical itparks ; nnc of them conimencea from 
tbe side of the jet, the other is inclosed and in- 
suldted nearly in its whole length in a glass tube: 
the tube and wire pas5 through the upper part of 
the stop-cuf:k, and the wire terminates on the out- 
side in t ball or ring E, at whirli sparks are to he 
taken from the machine, either directly or by a 
ehain. On the end of tbe jet is fixed, by c little 
socket, a smtU cspsnle IS, made of pUttnuro-foil. 
This ctipsuJc is pierced full of small holes, and 



urres as a grata to hold the diamonds. Its 
tance is obont three qnartcra of m- * ' t> Ckv 
end of the jet ; and the arm, by - -np- 

ported, is bent round, so that the f '^■^■ 

gen shall not play agninst it. The - 
by its lower termination, uo to h rm 
on a stand, and at the side of this pilUi i% *u t^fa- 
ture, by which a bladder filled with gas mty b|. 
connecteil with the apparataf. 

On using the apparatus, the diamond U 
placed in the capsule; and then the globe 
screwed on to the -itop-cock, the latter is to W r«' 
moved from the pillar and placed on the air-p 
the globe is then to be exhausted, and 
filled with pure oxygen ; or, lest the stream ofl 
gen in entering should blow away the diam< 
globe may be filled with tbe gas first, and 
dexterously taking out the stop-cock for i 
time, the dismonds may Iw introdiired, sad 
stop-cock replaced. The appamtus is then I 
fixed on the pillar, and a bloilder u( hydroj 
attached to the aperture. Now, passing ^ 
of sparks between the wires, a small str^ < 
dro^en ia to be thrown in, vthich intli 
mediately heats the capsule and diamonti; 
hot ; the diamonds will then enter into comt 
and the hydrogen may be immed'i'-'v t.ir«#4l 
and tbe bladder detached. Tbe dit<- 
liuue to bum, producing a strong ■< 
so far reduced in size as to be cooled too low 
platinum with which they lie in contuct. 
the flame of bydrni^n is used to heat the disi 
it is evident a little water will be farmed 
globe, hut this is of no consequence except 
tempts to detect hydrogen in the diamond ; tt 
convenience may be obviated, if required, by 
the flame of carbonic oxide. As, howcre-r, 
drogen has at any time been detected in tite di 
it ia better to use that gas as the heating agaatj 
then the carlionic acid, produced by the ooi 
is unmixed with that from any other soaroci 
maybe collected, and its quautity ascertained. 

Fig. 2 iii the method of illustrating the 
of the combustion of the diamond, as employ 
Mesws. Allen and I'epys : A A are mercariali 
meters, one of which Is filled with pure oxygeft] 
The brass lubes B B, properly supplied with I 
cocks, issue from tbe gasometers, and are 
with tbe platinum tube C C, which paasei 
the small furnace D. K is a glass tube 
Into the mercuriO'pueuroatic apparmtiu. by 
the gas may be drawn out of the gasometen^ 
convenient rcccirera. A given weight of 
Is introduced into the centre of the platinum 
which is then heated to bright redncsa, and 
passed over it, backwards and forwards, byi 
nately compreMing the gasometers. Carbontel 
is soon formed, and it will be found that i 
creese of weight sustained by the oxygen Is i 
lent tu that lost by the diamond; that the 
undergoes no cJiange of bnlk ; and that the < 
are, in all respects, similar to those obtcisad' 
similar combustion of perfectly pure charooal. 



SUSCEPTIBILITY OF VEGFT\niriL 
Op tbe suscepti bill ties of living f '^ 

common both to plants and anti '< 

proper to auimals only. laC. Tiain 
that is, the phystcalcapacity of exttn ^ 
taoeous contraction which ti fnutid hn Uc miinTit 
in primary tissues, is commoa to both. Thns,& 



MAGAZINE OF SCIENCE. 



27i 



um Ui a perpeadiculur position, the 

arm-pit is exteudtrd to mort^ than dau. 

r length ; and in the forcible bending 

h of ■ tree there is an rxtcnaion of n 

E. 2nd. Vital su«cr])tibilitr, or thaC 

liftng organ* wlttch eoables them to re- 

lo obey the impulse of stimuli, of the ini- 

bnd Dpvraiinn of which the individual 

Biiog, is cofDDion to both also. Thui the 

t ve lodgtd in the fioil excite the »uftce)t- 

|f the CAtreme fibrils or iiponKiuls of the 

firat udiiittt^d into, and then prnpelled 

ted Ihrouj^huut the fabric, while the in- 

ows nothing of it. Thus, altto, the 

animals is excited to action by the pre* 

aicnt, and the heart by the ini;(res« of 

thus are digeation, circulation, and 

dntained in the fabric without either 

l^e or onr notice. But, 3rd, Cerebral 

tjr, or that capacity of living organs 

lu9 thorn to receive and to obey tlie im- 

itnuli. and to transmit the imprf^sjon 

cunimnn centre of feeling and of coD- 

ifl proprr to animals only. Yet it has 

ed fur plant! aUo ; and the cluini has 

oed by botanists uf the bigbent celebrity, 

by physiulogLcal inquirers of no mrnn 

Dr. Watton, bishop of LUndaff*; Dr. 

le author of thr " [xivfs of Plants ;" Dr. 

t M«nrhesler ; and Sir J. E. Smith, the 

d Utc President of the IJnutean Society of 

kaYfi each uf them bei-n ndvocales for the 

F vegeUible seniHtion. Now, n doctrine 

y writers of sunh eminencff and (hstinc- 

surely have something in it. if not very 

at least very pliusible. Let us see on 

lion the doctrine is made to rest. 

e teveral orgvinenta addiii.vd in defence 

ne is thiit of the fiirt of the ex<:itability 

the notiiial giimvti of light and heat ; 

also alU-gcd, of cold and of di«rknesfl. 

t is Vfgetnting in a darlt cliaml>er, it 

f into any hole or opertu.e that may 

lor the admission of light. 2iid. Leaves, 

ed by lome insurmountable and acci- 

, do uniformly turn their upper surface 

L 3rd. The IcAvea of many plants as. 

ition in the night very ditfercnt from 

Ibcy occupied in the day. Thin pheno- 

Kus dcDominatcd tliu sleep of fitantv. 

wers of inuoy plants o]>cei and shut only 

boors or periods of tlic day. This, 

nomiaatcd the Horohgium Flora, — 

plants protrade their Icsves only when 

Care cf the atmosphere has reached a 

t of elevation ; some in January, some 

. and some in March. This, LinoKiu 

the Calemiarium Ftora^ 
nt for Uie above phenomena, Darwin 
vegetables the faculty uf sensation, and 
gns to them a tetutorium or onion 
rcaiding in each hud. We may fairly 
ipwever, that the mere susceptibility of 
lie to the stimulus of light and hcnC, is 
^ its being endowed with the faculty of 
becaase even in animals, which evidently 
Ration, tliere are still many roovements 
m individual is not conscious. Take the 
k circulation of the blood, nr of the pro- 
Itgeation. absorption, and nudttion, and 
good example of the fact. lieudt^s, the 
^1 and heat would amount to something, 



oven upon bodies destitute both of life and of feel- 
ing. Expose a piece of dyed rioth to the action of 
the direct rays of the sun, and yoit will <oon iH'gin 
to see its color begin to fade. Hold a sheet of 
paper or of parchment before a bright fire, and il 
will imiuediutely roll itself op into a scroti. Place 
a snow-ball in the same situation, and it will quickly 
dissolve into water. Try the ejcperimeut n|Mni a 
piece of net clay, and it will ahrinlc in all its di- 
mensions. Repeat the experiment upon a lump of 
wax, and it wilt speedily expand in vulume. Hence 
wc regard the bending of tlte stem toM-nrds the smalt 
aperture in the dark chamber, and the unfolding of 
the dower at a given temperature, ns being nothing 
more thun the chemical action of light or of beat 
attractiug or expanding the vegetable fxbrk', and 
thus focilitJiting the growth and nutrition of the 
plant. But vegeuiblea, saya Darwin, perceive not 
only the impression of ntimnli, tliey pcrreivc also 
negatives, and are consequently endowed with sen- 
aation. Culd and darkness are ucgstivei. Ad- 
mitting that cold and darkness are negatives, what 
do we gain by it after all ? If the atimului of heat 
or of light is withdrawn, its effect must uecesaarily 
fiubside, whether its withdrawal id perceived by the 
body that lias been stimulated or nut. If the paper 
or parchment is withdrawn from befnrc the fire, and 
placed io a cooler atmosphere, it gradually recovera 
its fonner shape without any perception of the ne- 
gation of cold. If we do not concede the ottribut^ 
of sensation to the phenomenon of the excitability 
of vcgetahlcfi by the action of the natural tlimiUi of 
light and of heat, it has hern tliouglit that wc must 
cotirede it to the phonoioenon of their irritability 
by the action of accidental and extraneous or 
artificial stimuli. The shrinking of the leafits of 
Mimosa puitira when touched ; the closing of the 
leaves of Dioncta Muxciptitax, and of several species of 
Drosera if a (ly but alights on them ; the auddeo 
incurvation of the filaments of Berhvria contmMnit 
if touched on tlic inner side, and the huty reflec- 
tion of the style of Stytidium fruticotum if the 
stigma is but touched with the point of the finger, 
are the rxsmplea of vegetable irritability whicti are 
usually adduced in support of the doctrine in 
question. 

hat still we have no certain or decided proof that 
plants are endowed with the attribute of sensation. 
The irritability which they exhibit upon the oppli- 
cation of accidental or artificial ftiniuli does nut 
prove the fact. Sir J. E. Smith found that the 
Atamcns of the flower of the Barberry retained their 
contractile power even when the petal with lis an- 
nexed tilamrnt had f«llen to the ground, and could 
no longer be said to be io a living alate. Bui a 
faculty \^hich plants may retain, oven when dead, 
il surely no proof of their having been endowed 
with sensation when nlive. Besides, they present 
no appsmtus whatever of feeling or of perception — 
nothing that is anulogoaa to the brain, nothing that 
Is analogous to the nerves of animals. Uut does 
nut (he Mimosa, it may be said, shrink ci'en from 
the touch ? There is a great difTcrence between a 
mere shrinking from the touch, and a shnnking 
from danger apprehended, as in the case of animal*. 
Tlie harlequin that is made of goldbeater's skin, 
shrinka from the touch or heat of the hand, and 
tumbles about as if it were actually altvc ; but no 
one, in spite of its whimsical freaks, supposes tliat 
it feels. Might not the phonomcnoD of the irrita- 
bility of pliinta be accounted for from the inHuenrji 
of the electric or galvanic Quid, withoat having 



i^^ 



27G 



MAGAZINE OF SCIENCE. 



recourse to the faculty of aensatlon ? Us dead frog 
Uu been made to leap by means of the sgeocy of 
this ponrer, and a dcsd man to khake hia tiat in the 
fico of the eiperimentcr. well might wc aAcribe the 
ihrinking of the Mimoia, the collapsini; of Dioniea, 
and the clastic spring of Stylidium, to a similar cause. 

Further, the advocates of the docttioe of ve^- 
table seoAibility contend that they find in vr^etables 
moTements that indicate not only sensation, but 
q1»o instinct. What less than instinct, it )ln^ been 
said, could direct the radicle in its irreaiatible de- 
scent into the earth, and the plumeltjl in its irre- 
sistible ascent into the air in the process of germi- 
notion ; or the tnining stem in Iti spiral ascent 
arounil its prop, never taken at random, bnt always 
in a determinate manner ; or the tendril to multiply 
its circumvolutioDS, till tt has got a hold that is in- 
sepamble ? The fact is, indeed, incjcpliciible on 
grounds merely chemical or mechanical, and yet the 
admission of instinct does not solve the difficulty. 
Neither do wc think the term is rightly applied to 
express the growth or direction of any organ or 
fsbric. The legitimate use of it seems rather to be 
confined to the expressing of the act of an indiridaal 
being regarded a« sentient. We might as well say 
that the upper growth of the teeth of the lower 
jaw, and the downward growth of the teelh of the 
tipper jaw, and the twisted and spiral growth of the 
boniB of the ram, are the result of an instinct born 
with, and inherent in, these organs. Thus the idea 
of the existence of instinct in Tegetables is palpably 
erroneous. Thu phenomena for which it is alleged 
to account ore the result of ¥itality, but not of feel- 
ing. Wc regard the term sjwntaneity as being Wsb 
ex<:eptionable titan that of instinct ; but still it ia a 
sjiontnncity thnt feeling has nothing to do with. 

Lastly, the advocates of the doctrine in question 
regard certain regetablc movements as affording In- 
dubitable indications, not only of sensation and per- 
ception, but of volition, desire, and design- 1st. If 
the roots of vegetables are lodged in the earth, they 
are found to have the power of protruding their 
fibres in the direction of the best soil. '2ud. If a 
Tesscl filled with water is placed within six or eight 
inches of the stem of a growing cucumber, tbe 
shoot will elongate in the direction of the vessel, 
and follow it till it reaches the water. 3rd. The 
movements of the leaves of Hedytarum pyrant ore 
perpetual, for they cease neither by night or by day ; 
and hence we are colled upon to believe them to be 
voluntary. 4lh. The water lily does not put forth 
its bloisom till it reaches the surface of the stream 
in which it grows, be it shallow or be it deep. 
&th. The style of Glorioaa auperba bends itself 
towards the stamens, and tbe stamens of Sazifroga 
bend thcmielvea down to the stigma, in obedience, 
as it has beeu alleged, to a sort of omorooi desire. 
(To be coHlinurd.J 



PHENOMENA OF THE BAilOMETER. 

TiiK phenomena of the barometer, considered as a 
weather-glass, hove been very differently stated and 
explained by various writers ; and they are so pre- 
carions, that it is extremely difflcalt to form any 
fixed and general rules concerning them. Althongh 
we have reoaon to believe, that the barometer never 
foils to indicate a storm, or any very great change 
of weather, for some hours before it occurs { yet 
its variations afford no indications or prognostics, 
that are absolutely certain, with respect to those 
leas ronaidcrable changes, lo which the weather is 



Bubjcct fo oar Tsriabb climate. With 
strirtions they afford some ground far probable i 
jecture ; and these restrictions are lo be deten&iacd 
merely by tbe sagacity of long-cootinned oba«rvs« 
tion and experience. Strictly speaking, the h«gbt 
of tbe mercury in tbe barometer has no imaedMa 
and necessary connection either with rain or ktr 
weather. That its variable bright is tbe immedisK 
consequence of tbe variable preasare of the itno- 
splirre, is a fact that admits of no doubt -, bnt lb 
causes of this Tariable pressure have not yet 
fully and autisCictorily ascertained ; and how 
state of the weather, in all its minute and 
changes* depends upon it, is a qaation thai ill 
to he determined. M. Pascal was one of t]ia( 
persons who particularly obKrved the variat 
the barometer, and referred theni tu correat 
changes in the weight of tbe air ; but be 
ledges, that it is very difficult to explain 
one and the other, as well ss the connectioaj 
aabsista between them. He observes, ia 
that the mercury is commonly highest in 
and lowest in summer ; that it is least 
the solstices, and most variable at tbe eqvii 
and he adds, in direct contradiction to later i 
ricnce. that tbe mercury usually (alls in fine we 
and that it rises when the weather becomes 
the air is loaded with vapours. M. Pascal 
lowed by Perricr, Beal, WalUs, Garciu, 
Lister, HsUey, Gersten, De la Hire, Mari< 
Cat, Woodward, Leibnils, De Mairao, 
Muscheabroek, ficc. { all of n bom have gtrevj 
ferent solutions of the phenomena of the 

The principal obserTations that hare been 
on the variations of this instrument, are 
up by Mr. Kirwan in the following partlcoli 

]. The more considerable elevations and def 
sioos of the mercary in the barometer happen al 4 
very short interval of time, in places very reaM 
from carh other. This correspondence was «^ 
served by Mr. Derham, in 1(*99, between tt> 
heights of the mercury at Upminster in Essex, flrfi 
Townly in Lancashire ; and afterwards by M,,,' 
raldi. between the variations at Pans and 
the distance of nearly four degrees of li 
adds, during these variations different windftj 
vailed at tliese places. But Mr. Kirwan o\ 
that where there Is a coDsiderable dilTe 
longitude, the like agreement is not found. 

IL Tbe deviations of the mercury frocB Itij 
annual altitude are far more frequent and 
in the neighbourhood of the poles than in 
the equator. At Pctersburgh, in 1725, the 
cury once stood at the amazing height of 
inches, if we may credit Mr. Consett ; and 
has been so low as 28. U inches. In the »c 
ports of France, the variations are greatar 
the southern : at Naples, tliey scarcely 
inch. In Peru, under the equator, and al thA| 
of the sea. they amount only to two or three ! 
of an inch ; but in other parts, within a fiew 
of the line, on the approach of the rainy 
of hurricanes, the barometer fulla an inch or: 

III. The variations without tbe tropics are I 
and more frequent in the winter, than in the 
months. 

IV. The variations are considerably smallffli 
very elevated situations than on the level of thai 
Thua M. Bouguer ob^cxTrd, that on the 
Peru tbe variations extended to ^ of an ia< 
Quito, elev.ited i)374 feet above the soi, tlisy 
prebend only O.0H7(hB of an moh. Ssuasurc 



MAGAZINE OF SCIENCE: 



277 



r*iUoD9 In SaTOjT, u did M. Lambert 

nd. 

mean height of the biroroeter on the 
e flea, in moat parti of the globe hitherto 
u about 30 ioches : M. Buuguer, UD^Ier 
b«^rvc(] it at 29.90B inches ; but as hia 
iraa not purged of air by fire, it stood 
it sboatd hnxe done. Sir G. Shuckbur^^h, 
I of aeveral observations on the roasts of 
England, found it at 30.04 inches, when 
-sture of the mercnry was 55^, and that of 
^ T^e mean height of the barometer in 
ttpon an average uf two ubterfatiotiit in 
of the jrear, krpt at tlie bouse of the 

ety, for many years past, is 2!). 88 ; the 
perature or height of the thermometer, 

to the same, being 58°. Tlie greatest 
ed by Sir G. Shuckburgh, Dec. 2Gth» 
London, was 30.U-(B inrhes, the thermo- 
at -l?"; and, rednced to the heat of 
I 30.UJ7 ; and tbis, be ssyt, is the greatest 
icb, as far as he bos been able to collect, 
r been known to stand at in any ooantry, 
icrrstinns hsre been msde and recorded, 
first invention of this inslroment. In tbe 

Rof the (loles, sayi Mr, Kirwan, the annual 
btfl of the barometer dilfer much more 
■taodard than in the more •outbern parts 
niqibere. 



ENGRAVING. 

/mm page 2-17 . and comcUuiett. ) 
t paper upon this snbject, we supposed 
r to bsTe proceeded with his work to com- 
oompsrative snccess, but that some re- 
ud alieratioDS were requisite ; we must 
these ill order to explain the cause and 
The remedy. First, then, we will imagine 
fTOund of the picture is specky where it 
rbc clean. This is called fslsic biting, and 
either from the ground being imperfectly laid 
(hat it has been injured during the tracing, 
lie injuries not afterwards properly covered 
p Brunswick black, to preserve the place 
^m the action of tbe acid. These false 
It be taken ofT by rubbing them with tbe 
r* or if ibey should be very deep, tbe 
Diay be applied fimt, and then the bur- 
in either case the plato meat be Bmoothed 
Is with the charcoal and oil, and (inalLy 
oil rubber. Second, suppose the lines on 
of the piste are too dark, so as to look 
tbe fore<ground, or not in sutficicnt gra- 
or if they require softening, as for 
aroand nnartiiitnal li^Ut.or in tbe gradation 
cy or a cloud. This want of keeping may 
i the imperfect or too long continued action 
ad, or ic may be cauned by the very nature 
ibject, or it may be aaid the very nature of 
It is seldom that sny very grcnt nioety is 
in mere etchings in gradation of shuJe, and 
m required, the graver is oanally employed 
op; yet withont thia much may be 
(he judlcioua use of the scraper, bnr- 
tnd charcoal. Thirdly, suppose a greyish 
over a part of (be picttlrc nhich should 
is a fault which arises from careless- 
occur to an experienced engraver, 
oner it is of frequent oecurrence, 
acid being accidentally epillcd over 
and which, although wiped off again, 




leares its stain ; or it may arise from wiping tbe 
plate after it is cleared from the ground with a rag 
which has been used before for wiping np such acid 
Bfi may have been spilled ou the tabic, and therefore 
has imbibed enough to do injury. Marks such as 
tlieae are often found on the margin of plates, 
arising from the biting in liquid penetrating beneath 
the bordering wax. Charcoal used with water or 
oil will mostly be sufficient to remove stains of tbe 
above description. The fourth and greatest fault, 
and that which is with tbe most difhrulty remedied, 
is that the whole is faint and wanting in decision 
and sufficient depth of color. This is the general 
result of inadequate biting in, and which arises from 
two causes : one of them is, that the action of tlie 
acid bos not been sufficiently prolonged ; the other, 
that the bubbles arising have not been brushed ofl* 
as formed. If the first is the only cause, tbe etching 
will appear very uniform and the lines prrfcct and 
delicate, and when examined by the microscope 
will look tolerably clear; but if the latter be tbe 
cause, then the lines will look confused, and being 
examined by the same microscopic test, it will be 
found that they present the appearance of a series 
of small boles, not by any means uniform in size, 
nor contiguous to each other. Let it be remembered, 
that whenever bubbles of gas arise, they form so 
many spaces from which tbe direct action of the 
acid is excluded, and the acid only acts upon tlie 
part of tbe lines between the bubbles, until these 
rising, leave the apace beneath again open ; thus 
irregularity of action must necessarily take place, 
and the result is as stated, and it is of that nature 
as scarcely to admit of a remedy ; hut when merely 
bitten in too little, the plate may be darkened by a 
proceas called re-bHini/, oue however to dIfficuU 
that many nn experienced engraver has completely 
failed in attempting it. It consists in laying n fresh 
ground upon the plate, nnd pouring acid upon it as 
at first, stopping the operation according to the 
judgment of the operator. The exact method of 
re-biting la this : — Warm the plate, but do not 
make it so hot as at first, but only aut&cientty lo 
to melt the ground composition, and cantnxe to 
keep it at this heat, either by laying it on hot paper 
or other substance wliich is a bad conductor. Rab 
on the margin of the plate a little of tbe etching 
ground, and using a tolerably clean dabber, lake up 
a small portion of the groond from the margin, nnd 
dab it gently upon the part to be re-bitten. If thta 
be done very carefully, it will cover the surface of 
the plate, and yet leave the lines free. To accomplish 
thi§, the success of the whole depends. 'WTien it ia 
thought that a sutHcicnt ground is thus laid, the 
plate has become cold, and the bordering wax ia 
made to surround it, a dilute acid ia poured on, (it 
must be much more diluted than in tbe usual pro- 
cess of first biting.) The plate must now be watched 
carefully, and if the ncid ia ae«n to bite on the 
general surface, it must be Instantly poured off, aud 
a fresh ground laid : on the other hand, if the acid 
does not bite in the linea, the purpose intended will 
not be accomplished, and a fresh ground must be laid 
in this instance as well as in the former, though from 
a different cause. Another method of re-biting ia 
more easy, but the etfect is scarcely so good. Uob 
a little whiting and water, made lo tbe con&istcDce 
of treacle, over the plate ; then wipe it from the 
surface, but still leave it in the Uoej, by exactly the 
same method as the copper-plate printer inks and 
cleans his plules in printing. Heat the plate and 
lay on a general ground. When dry or cold, aud 



2?S 



Magazine of science. 



bordered with wax, poor the acid over it ; this will 
break up all Uio lines insUiiUy, tind pcneCrtlc into 
Ibem. 

In every instance of re-biting, the plate moat be 
Tcry carefully cleaned, so that no ink whatever shall 
remain in the lines ; the best metliod of doing this 
is to warm it, and then, while warm, wash it with 
spirits of torprntine and pearl-ash water, by means 
of M rag.. A white coat of pearl-ash will most likely 
be left on the plate ; to remove this, let the plate be 
washed with warm water, it wlU then be fit for the 
Application of the re-biting ground. A fifth fuult in 
an etching is where the lines appear rough and 
rosrse, and tlie cloarr of them blended together ; 
this arises from the acid facing too strong, and in 
consequence of having broken away the edges of 
the ground aroand the lines, flo that they, instead 
of being deep and sharp, are sfaoUow, wide, otid 
ragged. The sixth and lost defect we shall mention, 
is when certain lines or small detached portions of 
the plate are pale, or appear as if untouched by the 
icid. This may arise from several causes ; tiret. 
from the etching needle not having penetrated through 
the ground, consrqoenUy the acid has not bitten, 
or perhaps from a Uttle grease having got upon the 
defective part before hiting it, whirh may also have 
impeded the action of tbe arid. Re-biting it • re- 
medy, if the disaster be extensive, or if Ihr hnes are 
not sufficiently deep to admit of this, retracing is 
tbe only resource ; if the defect is conflned to cer- 
tain small portions or lines, the procc&a of dry* 
pointing may be adopted ; this is merely taking a 
pointrd ntcfl wire (a needle is scarcely strung 
enough), aud scratching over the lines of the de- 
fective places, observing to clear off the roughnesses 
thus thrown up on the edges of the lines by the 
semper and charcoal. 

We hnve Ihtis minutely described the process of 
etching, as we have long practised it, and truiit that 
DO part of the art has been omitted in tbe above ac- 
count ; at the same time the tyro muKt not expect 
that it is pouibte to describe any art of so purely a 
practical nature as this, so as to leave no diBicuIty 
for him to surmount, and mnch must be allowed for 
experience, tact, and facility of eiecution, but with 
ordinary attention, these minor difficultiea will be 
soon removed. 



P 



ACTION OP ISINGLASS IN CLEARING 
MALT LIQUOR. 

nV MB. iJAUtJKL ROBERTS. 

In explaining the action of isinglass in clearing malt 
liquor* two subjects present themselves for particular 
eonsideration. 

The first is the nature and properties of isinglass. 
The second is the change which takes ploce in malt 
Uljnor during the process of fermentation. 

The best isinglass is obtained from the M)und9 of 
the fish of the genus Accipenser, especially from the 
sturgeon, found in tbe Danube, and the rivers of 
Muscovy. It is alio obtained from the sounds of 
the Beluga, and Huso Gcrmonorom. 

laiiiglou is almost entirely gelatine, 9S parts in 
every lUO of good isinglass being soluble in boiling 
water. 

Tlie properties of gelatine must therefore be con- 
sidered, it being analogous to pure isinglass. 

Gelatine is distinguished from all animal princi- 
pies, by its ready solubility in boiling water, and 
also in most of the diluted acids, which form ex- 
ceJJertt iohcnu for i{. 




Gelatine i< perfectly insoluble in iloobol. 
almost er]ually so in cold water. It is prvcipitatnl 
from its solutions by infutiona of tannin. 

An infusion or tincture of gtlls, will - 
it from its solution in ri.OOO tinira iU wai^i 

These are briefly the propcrtlea of ;^ j 

pure isinglass, which should b« bonte in mud v 
operating on it. 

A great variety of isin^Iaaa is offered for sal*, at 
a range of pricea from three to aUttfcn shilltoi;* pv 
pound : and the relative value of each kind maj ha 
known by the following tests : 

la the first place, isinglass should rrm:,m .,n. 
changed by being steeped in spirit of wide 
from 50* to 60 over proof, in which t; ' 
chemical principle of isinglass) iA 
alcohol, or spirit of wine, in wbich ' 
been steeped, should then be tried 
of tincture of galls ; if tbe liquor i 
unchanged, it is much in favor of u..^ .. 
the isinglass. If, on the other hand, llw 
galls causes a precipitate from the aloohdlio 
the isinglass is not pore, as it cootatns sometU^ 
more than pure gelatine. 

Different samples of isinglass which ha>> 
unchanged in alcohol or spirit of wine, t. 
be tried by the two following nietl '- 
opinion can be given as to tht-ir rel 

given weights of each sample (ou- 

ounce, for instance, in threu ooncca ol watn- 6f 
measure) in separate vessels; bring Ihem gmdullf 
to a boll, occasionally stirring each sample. Wbib 
hot, strain the different solutions through moslifit 
into separate vessels. In pro[inrtion to the qmntUy 
of undissolved matter left upon rarh strainer, may 
the solubility of the different samples be asrerlatn«d; 
that mhich leaves the least reiidaum will [■>nTi. 
when cold, the strongest jelly, ujton mlmti ito 
clearing property of isinglass depends. The n* 
iiiaining trial to which tbe different sample* srvls 
be submitted, is the last aud most der:- 
Equal weights of each sample (the one i 
an ounce, for instance,) arc to be cut ■■ ' - 
pieces, ond each one-fonrth of an 
holf a pint, uf hard or suur beer, 
vessels containing the different samples patiotoia 
apartment, at from 6^^ to 7&" P.. and olkwed to 
remain there for three days, stirring each saai|dl 
very well, once or twice a day. 

At the expiration of that time, thf rr will be tt 
evident difference in the strenf^thof ra:-h jelly, pro- 
vided different qualities of isiuglass hud hern ui^ 
mittt'd to the ei|>criment, and ntmi tlie thirk«i( 
jell]! has a small quantity of the tiii<-T' 
applied to it, and stirred through it, 
the gelatine from the sample of i 
form of a thick jelly. The other 
afforded a less solid jelly, will give, v 
galls, when stirred through it, a smaii<t 
gelatine in the form of thick jelly. 

From the strength of the jelly given, by a»J 
sample of isinglass steeped in the above proportis* 
of ioor beer, (such as brewers use iu making dan* 
ings,) and submitted to a temperature not exccedii^ 
75^ v., may he ascertained the relatire value of tbA 
sample, as upon the strength of the jelly, and, cod- 
•equently, the quantity of gelatine rootainetl in U9 
isinglass, depends ita valnr in rlrHriiiK nudt Uiiuor. 
The best short-staple tsinglasji is aJways solnUc tt 
boiling WBlcr to about 1-OOth residue. 

Ill tlie preparation of brewers* clearictga, isJiigJlML 
of a good quahty. is 9tee|rod in odd beer, in •■ 



iMM 



rii" 



J 
')^i 



MAGAZINE OF SCIENCE. 



279 



or«buut 50^ F. temperature. After Mtne 
UinglMR i» converted into a jelly bj tlift 
of the hard beer, it bcin^ one of the quidities 
itinf. to be soluble in dilute acids. 
advAiiia^e arisett to the brener, in always 
[ btH clearitigtt from sutir brer of an uoironn 
h o( acidity, by which meaos be is protected 
ay disappointment re«ultiog from the strength 
clearings he oaes, provided he won prenously 
of i)ie good quality of the isinglass he sub- 
to the action cf the tour beer, 
mpli: method may be taken to try the acidity 
t Itquor, of which a brewer intends to make 
gs. Make a standnrd liquor of one part (by 
) of the b)-carbonaie of potash, dissolved to 
I parti (by measure) of wnter. 
ose, for example, that sixteen fluid ounces 
d porter to be tried, is put into a Tessel 
ntain abont douhl<* that quantity. 
y measure a given portion of the standard 
ly four fluid ouaces). Add small quantities 
dard liquor to the acid porter, stirring 
!sture upon every addition, until the efler- 
;e cetLses,^ or until the mixture ia so neutra- 
siandard liquor, as not to chaoge the 
litmus paper wbi^u it. is dipped tu. The 
y farther be tried by turmeric paper, 
Id be changed to a higher color by the 
thereby showing that the nlkalt of the 
r is slightly in excess. — By tl»e quantity 
liquor required to produce this result, 
nown the greater or lens degree of acidity 
porter to be used fur making clearings, 
fen tluid ounces of acid porter, lueh as is 
f one of the largest breweries in Ireland for 
loariogs, standing l'' Twaddle's hydrometer, 
peretnre, required four fluid ounces of 
liquor to neutralize it. which is equal to I 
bonate,of ]>otii8h toG4 parts of acid porter, 
|>pears a good average strength of acidity 
when required for making clcaringi. If 
required less standard liquor to neutroUze 
Ihe above quantity, it would indicate a 
of acidity, which would render such porter 
kct solvent for isinglass. 

such as the above trial was made 

npon isinglass, at 01° F.,bnt its action is 

Uitated by an increase of temperature of 

"F. 

the fermentation of malt liquor, the sac 

attcr of the malt is gradually conrerted 

hoi, by the agency of yeast and atmos- 

air: ultimately the liquor passes from the 

intu the acetous fermeut^tion. 

latter state is prevented by the exclusion of 

heric sir ; hence, the necessity of bunging 

y malt liquor, when the vHious fcrmeutxlioa 

plete, otherwise the liquor will become sour. 

when unltned porter is pat into casks, and 

Wa fermentatioo has, either in part or en- 

eetsed, that brewers apply the clearings to 

i advautage. The manner In which isinglass 

ion unfined liquor in clearing or Aning it, is 

pertica of gelatine (the cliemical prin- 

inglass.) First, its solubility in weak or 

9 ; and, secondly, by being perfectly in* 

aleobot, and sparingly soluble in cold water. 

clearings, or isinglass, in combination with 

eid beer, is applied to malt liquor in a 

▼iuouR fermentation, the alcohol of the 

gages the gelatine of the isinglass from 

a in the acid porter, and, being thus 



liberated, it carries with it the impurities of the 
liquor which were suspended in it. 

The fultowiug experiments will better iUustrite 
the theory : — 

Mix a small quantity of brewers' clearings nith 
cold water. In a short time the greatest part of 
the isinglass will be separated. 

Filter the mixture through paper, and if s few 
drops of tincture of galls be added to the filtered 
liquor, a small portion of gelatine will be precipitated. 

This shows that the acid of the cleariuga held a 
small quantity of the gelatine in solution. This is 
further proved by adding tu the filtered solution as 
above, a few drops of liquor of ammonia, instead of 
tincture of galls. The liquor of ammonia should be 
cautiously added in sufBcient quantity, to neutralize 
the acid contained in the clearings, when'the gela- 
tine, which was previously held in solution by the 
acid, is liberated. By this experiment i* shown, 
the solubility of isinglass in acid porter, and nearly 
its total insolubility in cold water. 

Again, dilute a small quantity of clearings with 
cold water, until its acidity is so far overcome, as 
not to redden litmus paper, when applied to.it. Tl»e 
isinglasfl of the clearings will be cooipletely seps- 
rated from the mixture ; fur, if a few dropa of the 
tincture of galls be added to Ihe filtered solution, it 
will remain unchanged, 

Add hot water, at about 180° F.. to another 
small portion of clearings, until the liquor is so 
much diluted as not to afTect litmus paper when 
dipped in it, as in the previous experiment. Fitter 
the liquor through paper, when cold. Gelatine will 
be detected in this solution by adding a few drops 
of tincture of galls. This shows the_flolubiltty of 
isinglass in hot water. 

The next experiments will more clesriy show tlie 
influence of alcohol in separating gelatine from its 
solution in weak acid, by which its action in clearing 
porter in a state of vinous fermentation, is explained. 

To sixty parts of cold water, add 'one part of 
alcohol, and into this mixture put a small quantity 
of clearings. In a short time the iilnglnsa will be 
separated from the mixture, and the liquor will be 
clear ond bright. If, however, the liquor be filtered, 
and a few drops cf tincture of galls be added tu the 
filtered solutiDu, a small portion of gelatine will be 
disengaged. This is caused by the free acid of the 
sour porter, of which the clearings are made, hold- 
ing this small portion of gelatine in solntioo, as it 
may likewise be separated by adding a few drops of 
liquor of ammonia, instead of tincture of galls. 

Rc^-c^se the experiment by nsing hot water at 
180'^ F,, instead of cold, adding the ssme quantity 
of alcohol and clearings, as in the former experiment. 

After the mixture has been allowed to settle for a 
few hours, it will be found that there is but a partial 
separation of the isinglass, and the liquor will not 
be so clear as in the former trial, the reason of which 
is, that the hot water dissolves, and retains in solu- 
tion a portion of the iainglo&s of the clearings, the 
remaining psrt being separated by the alcohol, In 
which it IB insoluble. The etfect would be exartljr 
similar upon malt liquor, if clearings were applied 
to it which had been miide with on excess of acid 
beer. The nlcuhnlof the nnfined porter would dis- 
engage but a small portion of isinglass from the 
clearings, the remainder being held in solution by 
the excess of acid in the porter, the disengaged gek- 
tine carrying with it |>articles of vegetable matter, 
which, when suspended in the liquor, rendered it 
but sctui-truispareat. 



Afti 



280 



MAGAZINE OK SCIENCE. 



SIZE OP SKY ROCKETS. 
Wr have been to n-peatedly uked. particuUrly 
during the last month, as to tho cxHct diamettr of 
feky rookets, that ne give the roUowing: tabic, trust- 
ing it will be sutlicient to %atit{f all our friends. It 
is to he remarked, ihst a line it a twelfth part of an 
inch : — 

«.,., ^, InUrUir diameter Lvnglh of 

IC OS 19HinM 12-2inc]ics. 

12 17 11-3 

8 15 1012 

4 12i 7-75 

2 91 6-2 

1 7i 4-9 

i H 3-7 

■MISCELLANEOUS EXPERIMENTS. 

Curious Motion proiluced in Z,iquidt by Heating 
and Ccolittg them. — Fill a large phial ftith water, 
and pot into it a small quantity of powdered amber, 
having previounly added to the water n sufficient 
quantity of potaab, to make a aolution of the Mine 
sjwcitic gravity as amber. Iiainerse tlie phiiil lu a 
glaaii of bot water ; upon which a very nngnlar 
Internal motion will be immediately perceived. A 
current of the fluid will riiir up tlie sidea of the 
phial, and another deaceitd in the ccntreof it. Now 
take the phial out of the hot water, and observe the 
ejects of its cooling. The currents will be reversed : 
the eitcmal one will descend, and the uiernat one 
uftcend. — The use of the powdered amber is to make 
the opposite currents into which the water is thrown, 
visible. 

Hotutiom qf Soap in Alcohol is employed to as- 
certain the comparstire hardness of waters. With 
distilled water it may be mixed, without any change 
ensuing ; but, if added to a hard water, it produces 
& milkinesB, more cotuiderable as tbe water b less 
pore ; and from the degree of this milkiness, an 
eiperienccd eye will derive a tolerable indication of 
tbe quality of the water. This effect is owing to 
tbe alknli quitting the oil whenever there is present 
in a water any substance for which the alkali has a 
stronger affinity than it has for oil. Thus all un- 
combined acids, and all salts, excrpt those of alka* 
lies, decompose soap, nnd occasion that property in 
waters which i« termed hardness. 

7b *A«i.' that Hot Water m Lightin- than Cold. 
— Pour gently hot water into a tall gloss nearly 
filled with rold water ; it wilt remain on the aur- 
fMce : but if cold water be poured upon hot water, 
it will sink to the bottom. This experiment may 
b« rendered more «tiikiog by coloring that portion 
of water which is paured in. 

Prepare a strong solution of phosphorus in sni. 
phuric ether, and dip n piece of white silk in the 
solution ! then, when the ether has evaporated, «od 
the phosphorus begins to fume, opply a Bolution of 
Ditro-raoriate of gold, made by dis.<K}lving tbe crys- 
tain of that salt In distilled water : tbe silk will in 
an instant be covered with a njttendid coat of m?- 
ffl//ie pold. 

Proceed as in the last experiment, and. instead 
of the aolution of gold, apply, vrith a caiiiefa-hair 
pencil, a solution of nitrate of silver. Here ttie 
silver will instantly be restored to iu metaliic bril- 
liancy, and fre^iuently attended by tpangtet of a 
beautiful blut. 



If a bit of white ailk be immersed In »u etttfetl 
solution of gold, and dried, the appIIivL!ui:i L'f pluis- 
phorixod ether will only ioipArt ■■ It U 

tlie silk ; but if, OS soon as tbe |: -{Uti 

to fume, it be placed on tbe palm of tlic h.kud, vA 
breathed on for a considerable time, the A/ttiea«|tt 
be succeeded by a purple tinye, and tbe laiMSr 
hutre of tbe gold will soon be^n t^ appear. 

" An aqueous solution of nitro-muriate of loU," 
says Mrs. Pulhsme, " was poured into o cklniaf 
containing kouic phoaphorizcd elhrr : iustsnttrw 
gold began to assume its metallic vpl 
tended with n variety of colors, %% yurpl- 
red, tho beauty of which cannot be drs'-r ' 'i; 
which depeod on the different drgievy ■d tU 
reduction.'' 

With a needle pass a thread through « MuUbtt 
of phosphorus, previously fmd from muistiuc lit 
Immersing it In alcohol. If this be S)i 
an aqueous solutiou of nitro-muriatc ol . 
few minutes tbe photphonu will become cuinci 
vith pure yoid, 

IF n piece of white *ilJi be dipped in an ^|itH» 
solution of nitro-muriale of gold, and capOMdvfaik 
wet to kulpburuus acid gas, the whole plee* wUl. !• 
a few seconds, be covered with a ooat of rtdufi 
gold, which remains ptrmwMnt. 

If a piece of white silk be Immersed iii 
solution of nitrate of silver, thorou^ttly .i: 
dark, and then exposed to sulphuio 
it will soffer no change; nor, if it 
alcohol and then replaced in tbe i.i|>.'u>. -m f<'< 
sign of reduction appear ; but if it be wotlcd «)tk 
pure water, and then exposed to the vapour. ■*• 
taltic silver will immediately be seen on tts sur&cr. 

Dip a piece of while calico in an oti'ieout vnlorifls 
of acetate of lead, and then drop & 
sulphuret of potsjis upon it. If tl 
in the palm of the hand, the Itatl ^ui m- <>r>ki-T*ni 
gradually to revive, and will soon be reduced Ifi it* 
Metallic state. 

Dissolve some sulphuret of polasa in klailiol, ut! 
immerw a slip of white silk in tlte snluu.:n. 1/ 1 
drop of an ar|oeon9 solution of rulphate of Ma*- 
ganese be now applied, films of mttaltic mtt^foni't 
bright us silver, will instantly appear. 

If a bit of silk be immersed in dilulMi ^ct^Mii «f 

lead, and exposed widle wet to a ?■' -* -■ !'\u. 

retted hydrogen gas, a brown tin >U; 

diffuse itself, like a passing abado<-, • j<^ 

surface of the silk, accompanied with a bri|ikt cwl 
of reduced lend, rejemhling sllrrr. 

If a piece of silk be immeri" 
tion of muriate of tio, and • 
stream of the asuc gas, reducm i 
ness will immediately cover the 
little time this will be aceompi...... 

colors, such as blue, orangt, sod parpie. 

A piece of silk, treatni in the -^i i.^ wm, W 
dipped m an aqueous solution of n- 'xir. 

will be covered with respleodrnt ■<• 

attended with a citron yellow cohr. 

Prepare two glasses of very dilute mtrate of 
per ; into one drop a little liqoid ammoais, oad 
the other some diluted arseoiato of potass, 
addition of these two colorless solntiona alA 
duce very different effects ; for the one fl 
have an abundsot precipitate of a brilliaDt 
blue, and the other a precipitate of a beautifat 
green. 



LflsiDoa.— Prutcl by tl. FnAini. B. White Hnn» Lane. Mll« Knd — Puliliihed hy W. Bam-m. 1 1 . PaitfaMH «•• 
Kdloburgli.J MivsiEL— Gln*(ow, 1>. Bates aiM) J Bashs — Liverixxil. G. Pniiir, 



383 



MAGAZINE OF SCIENCE. 



THE DORIC ORDER OF ARCHITECTURE. 

The must ancient Grecian order of architecture 
vu first uKd in bnildiiig the (empli! of Jano, aC 
ArgM. at the period when Dorof. father of the 
Dorians, reiKned in the IVloponneaus ; though, ac- 
cording to Vitruvius, ita Bjmmetry and proportions 
were not fixed till Ion, the nephew of Doms, snd 
chief of the lonmn% led tin Athenian colon; into 
that part of Asia Minor, which was afterwards dis- 
tin^ished by his name, and there butit a temple, 
aftfir the fashion of those in tbr Dorian states, the 
colamns of which were six diameters in height, 
taking the proportion from the ratio that a maa'd 
foot bears to the height of bis body. 

The columns of the Doric order, with their en- 
tablttturo, are imitated from the hovels of the ori- 
ginal inhabitants of Greece, consisting of roofs 
supported by the trunks of trees. The colunina 
were lluteid, for the convenience of resting the spcari 
or slaves, which the early Greeks always carried 
with them. The cnpital consisted of a large convex 
monlding, in the form of a bow, and a square stone 
to keep off the rain. The parts resulting from 
the primitive habitAtton were carved into mouIding;s: 
thus, the architrave represented a wooden beam, and 
was of a single stone, or block of marble. It was 
furnished with a projrcting band, covering the moa- 
sive face below. The frieze was an imitation of the 
ends of the beams ; the intervals between them were 
ori|;ioallj left open, though afterwards they were 
closed in the form of sank panels, and the pro- 
jecting ends of the supposed besms were cut into 
vertical channels for draining oft the rain from the 
anrface : these cut ends olivoys began at the angle 
of the building, and obtained Uie name of trigtyphu^ 
on aooount of their having two angular channels in 
Am middle, and two half channels at Ibv comers. 
The channels themselves were called glyphs, and 
were each formed by two planes, meeting internally 
in a right angle, and each plane externally forming 
an angle of 135 decrees with the outer surface : the 
■emiglyphs at the extremities, also made an equal 
ugtfl with the front. Beneath the projecting band 
of the architrave, and under each triglyph, was a 
fillet, having six guttie dropping from it, and cor- 
responding at the ends to the vertical sides of the 
trigljrph. The cornice represented the projecting 
timbers of the roof, and the under side of the rafters 
had small conical or cylindrical bodies sculptured 
cm them, in imitation of drops of rain. These were 
termed ffutfte, and couiibted of tliree rows under 
each rafter, each row containing six guttie. The 
spaces, or panels between the triglyphs, were called 
meinpw, and were generally of a square figure. The 
ends of the rafters were denominated mutule*, and 
were placed one over each triglyph, and one over the 
centre of each metope. With the exception of the 
Doric portico at Athens, that of Philip of Macedon, 
and that of the Temple of Apollu, at Delos, the 
faces of the triglyphs being the same plane vrith that 
of the architrave, or epistylium, the metopes are 
recessed ; but in the instances quoted, they are 
otherwise. The columns diminish either in a curve 
or straight line, from the bottom to the top ; and, 
as alrendy observed, are generally Huted : though in 
the temple of Apollo, just adverted to, and in that 
at Segcsta, they ore pluin. The flutes are for the 
most port twenty in number, without ttUrt«, and 
terminating under the annulets of the echinus of 
the capital. 
, SBch are the general cbaracteristica of the Grecian 



Doric, which is almost constantly placed on tbrestr 
four steps, proportioned to the msgnltuda of tW 
edifice, and nut tu the human step. 

The remains of this ancient order are to be UmA 
In Greece, the place of its invention, and in tliv 
Gretrinn colonies; iu Sicily, ami at Psestum, in 1 
to whirJi may be added a few fragments to 
These antiqae examples are of a sufficiently 
character to denote its pecnliar style or speoii 
Egyptian buildings, and those of other naiii 
a date prior to those of Greece, having entab 
supported by columns, br^r much rrseoib 
an order ; but as they have no specific fono^. 
differ in other reipcctA from all the Gre^an 
they cannot prevent as from nttributing U 
Groekf the invention of a style of building wbi 
to be found nowhere but in their own edifinea. 

We have already mentioned the temple of 
in the island of Delos, and the temple at 
in the former, the shaft of the column is ool 
exeept at the neck, and a flmall portion of Che 
eod. In tlie latter, the shafts are not fluted, 
the necking is formed by making it rcr 
the surface of the upper p&rt : a recess i^ 
observed in the lower end of the shaft ; bit Fij[< 
these receding annnlur eurfaeea are smooth, and uet 
sculptured into tlutes. as in the former exaoDpl 

In the portico of King Philip, in the t 
Delos, a straight moulding occupies the plaoe 
echinus, and is nothing more tb&n an inverted ctrtuA 
frustum. The proportions are very light, and ou^ 
be appropriately adopted in private buildings, «r 
works of gaiety. 

The largest example of the Doric order, 
is in the temple of Jupiter, at Selinus, wh 
height of the column is 48 feet 7 inctiea : 
lower diameter 10 feet 7yb inches ; nolike cfsrjT 
other specimen of tJils order, the flutes are ie|i^ 
rated by fillets, as in tlie Ionic and Corinthian or>ierk 
In the temple at Corinth, the shaits are diminialM^ 
in a convex curve, from the foot upwards, to iS 
termination under the annulets. These colooH 
have the fewest diameters In height, whence U b 
supposed to be one of the most aacicut examples of 
this order. 

The interior peristyle of the Hypiethral tempW «t 
Pestum, presents a double ran^ of columns-, oai 
above the other; in which tlie lower diameleieff 
the upper tier are not equal to the superior Jiauisi— 
of the columns of the mfcrior row ; but, the stdtf 
of both ranges being continued tn straight tmcs. 
they may be considered as parts of the some eo»i 
with tite omission of the intermediate frnlaib 
which is occu])ied by the podinn. The sh'tfa kn* 
only sixteen tlulea. In the exteri 
shafts are low, and have a bold pr.. 
whence, if we may form a judgment tA tha aatH|HilJ 
of this order by the proportions of the ooIaaHk%ta 
may rank this example next to that of the Mfl^ 
of Corinth. 

The temple of Minerva, at Syracuse, is i 
able in havug the columns placed upon |»1 
round the exterior peristyle, while those wi 
pronaos, wliich are likewise on plinths, have wxM* 
inga abore. forming what has been called fAe Ihrit 
base, with tdl the specific members, though not of 
tlie Ufiual proportions. The capitals hare an astriftl 
and fillet under the echinus, instead of ann 
in all other Grecian examplfs placed in this 
tion; in which latter respect, it bears 
affinity to some of the Italian exampla sobM^i 
to the rcttoretion of the Roman style. 



MAG.VZixNE OF SCIENCE. 



283 



Id the p»etido()iptrml temple Ht P«stani, the 
»eckl»g of the capita] is irceisnl, us in some oF the 
•iMMBplM iKove ; and, contrary to the distinctive 
flfaifi]ieit7 of (lie Done order, has a row of leavea 
nMUd U, bendiof tlieir tops dovrnwards under the 
auinleta. lite latter deviation i« atio to be otiierved 
is the bciastyle temple nt pRitum. 

The temple of Theseus,' at Atbeiu, now St. 
George's charch, the most perfect of the Mcred 
■dtlEeM of that place, i!i a very clesnnt light exam- 
T'^ ""^ " ' -uiitcd for decoretto; private dircUiass. 
portico at Albens, ii another very 
^> ^it example, and applicable to the lame 

■•«•• Tbti, and the temple of Minerva, are the 
onlyGredoDeiamplea in which the crowning echinus 
ji entire. 

The Doric of the theatre of Marcellot, at Rome, 
'' 'v rcmninini; example of the Komtin taste, in 

Itrr, is qnue out of character; for it wants 
...^ ...utiile*, which arc a peculiar feutare of the 
Of4onnance, and their place is occupied by dentila, 
tiM distingniihing marks of the Ionic. The middlti 
ef the tri|;lyi)h is in a plane passing through the 
■lis of Che column, ot right angles to the face of 
the epistylium. The shaft is too slender, and rather 
rspreaeots a wooden poat, than a column of marble 
- 'lie. The capitnl, also, is orerchargcci with 
;its, and the whole is deatiluto of the elegant 

. , i(y of the true Grecian Doric. 

In the hciastyle temple at Piestum, the entabla- 
ture, which appears to be altogetlier Roman, ia 
Without mutules, the aoffit of the corona li coffered, 
and the capital has a row of leavea under the an- 
aoleti ; bnt the columns bear a nearer affinity to 
the Grecian tbnn the Roman style. 

Previoua to the Macedonian conquest, the Doric 
VM the only order known in Greece or its colonies; 
■td chough the remaining examples are of various 
Moporiions, yet thoie of the members of the cnu- 
u^^re are so very uniform, with reapect to each 
other, that we may venture to ley down the following 
as the general recnit; for public buildings, the 
culumna may be five diametem, or Ave dianieters and 

• half in height, and for private dwellingg, six t the 
dimination may be one.fuurth of the inferior dia- 
meter. The height of the nnpital mny be two-fifths 
of the lower diameter, and mny be divided into two 
e({Qat parti, one of which may be f^iven to the aba- 
ca». the other to the echinus luid annuletji ; the 
taller may be subdivided into five equal part*, and 
fonrof them taken for the echinus, and the remain- 
IflC one for the annulets. The height of the enta- 
bUlare may also be divided into four equal parla, of 
«hirh one may be given to the cornice ; and the 
Other three being subdivided into tno parts, one 
past may be given to the epistylium, and one to 
the frieze, or zopborus. In the Roman Doric the 
colamna may be eight diameters, and set on a sqanre 
plinth. Tike abacus, also, may be ornamented with 

• tffltll ogee and Allct on the upper edge. The 
ntercolnmnintions of tUe Doric order are determined 
hr the number of tnglyphs which intervene, initead 
of the number of diameters of the columns, as in 
Ibe other orders. 

To exemplify this order, we turn chosen that 
bcantiful specimen, the temple of Neptune, one of 
tkt three temples tttU remaining at Prestum, while 
the nearer srcne is part of the remains of the cele- 
brated Partltenon, at Athens : so much of the frieze, 
*nd so many of the metopes of which are now in 
lite firilUb Museum. The cut gives n good idea 
mi tlie ancient templet oclonging to this order. 



SUSCEPTIBILITY OP VEGETABLES. 

[li^iumed frum fige Vt, atui conrlHiM,) 
Sucu are the indications which are thought to de- 
monsrrale the existence of vegetAble volition, desire, 
and design. Yet the direction of the root proves 
only the agency of n aort of physical or cberairal 
ottraction between its extreme fibrils and the soil; 
and the direction of the stem proves only the agency 
of a aimilnr attraction between the young and tender 
shoot and the water, like the attraetion of the nag- 
net for iron, or of a rubbed cylinder of glaaa for a 
tuft of thistle down. At the beat it is but a Tege* 
table locomotion. The shoot does not walk towards 
the water, it only grows towards it. l*be pheno- 
menon of the self-moving leavea of Hedysarum 
ffyrxnut participates more of the character of animal 
spontaneity than any other movement hitherto ob- 
served in Tcgetabtes ; and yet it ia but a solitary fact, 
and cauDot establish a position that muat rest on m 
copious induction of particulars. How is U that its 
movements never intermit ? In this they resemble 
rather those movements of the animal system that 
are wholly involontary, for auch have no intermis- 
sions ; whereas the movements that proce<ed trom 
volition soon begin to induce fatigue, and have fre- 
quent intermisiiions. If we were to grant that the 
wiitrr-lily grows by volition, we should be granting 
too much : for even man, who stands at the head of 
the animal creation, cannot grow by volition, and 
cannot add au inch to his stature. The sympathy 
subsisting between the stamena and pistils is very 
aingolar, and very surprising ; but the amorons 
desire which it hns been thought to indicate, and the 
consequent movement which it has been thought to 
cause, arc merely the work of a glowing imagination. 
It was a fancy entertained by some of the earlier of 
the Greek philosophers, as we team from Aristotle, 
riir^ fvTuT, and it has been sung most dcUgbtfally 
among modems, by Dr. Darwin, in bis *' Loves <k 
Plants." The reader is overwhelmed with the 
beauties of diction, with the harmony of numbers, 
and with the novelty and apparent plausibility of 
(he doctrine, and Is almost persuaded to become a 
Darwinian ; though the doctrine is any thing bat a 
legitimate deduction from the phenomena of vege- 
table life. It is a very pretty poetical fiction, but s 
very unfounded philosophical fact. Let us regard 
the phenomenon as inexplicable, rather than admit 
a aolution that is unwarrauted and un warrantable. 

Some have thonght that we ought to oicribe sea* 
sation to vegetables from the similarity of their 
structure to that of animals. \\'hat though Darwin 
has called certain vegetable organs veins, others 
Dcnes, and others arteries ? Their functions are in 
no respect similar to the veins, nerves, and arteries, 
of the animal system. You canuot prove the ex- 
istence of a real circulation ; you cannot point out 
the propelling organ. Where is the heart, where is 
the stomach, where ore the intestines? Where la 
the proof that nerves reside in the bud, and where 
are the mUHctea which (hey put in aotion ? Even the 
analogy of leaves to lungs is very faint, but it is 
better founded thaa that of veins and arteries ; and 
hence leaves have been regarded from time imme- 
morial as being the veritable lungs of plants. 

Finally, some physiologists, among whom we may 
place Sir J. E. Smith, have believed that a legitimate 
argument for tlic sensation of vegetables might be 
drawn from the fact of the benevolence of the Deity, 
regarding the endowment as having been conferred 
for the v^^^ow *^ «iX«vM4\n% xJut \»\t«tt«fc^V ««^* 



284 



MAGAZINE OF SCIENCE. 



Bcioiu exUtence to an additioiul and incaltrolably 
BUioeroui clan of individual beings, which are 
rendered peculiarly iDtermting to man, both from 
their beauty and utility. Bat aa rc^tablm are ex- 
|iOftfd indischminately to the perpetual atucks both 
of meu and of iiuluiali, without having; any elTtfctual 
means whether of defence or t-scape, Moaation could 
hardly be regarded aa a benetil to them, if they were 
even endowed with it. [t would mther be the lucaria 
of aflccting them with psin. They are cat, aad 
cropped, and mai^led, and mowed down, and still 
tliey are obliged to lire and (o auHer. U you nay 
that animaU luSer aUo, and that God ii yet good, 
—we aoiwer that the caaea arc not altogether the 
same. Tho lowest animal tliat exista haa always 
•oroe meana or other of defence agaioat, or eacape 
from, the attacks of other animaU, or of man. 
The animal, consequently, has a chance for the pre- 
servation of itfl life, which the plant has not. If 
you Hj that the strongeat atill prevaiU,ur that mat), 
who b placed at the head of the animal creation, 
does not scruple to alaugbter such as are good for 
food, or to destroy such as have tlie mraos of an. 
noying him, — we acknowledge it to be a law of na- 
ture that one species of animal ihall live at the 
expeiise, or by the destruction, of another. Mao 
is eren the destroyer of man ; yet it is not often by 
a destruction that is piecemeal. It is not by the 
cutting off of one slice to-day, and another slice to- 
morrow, from the hip of the devoted victim* as the 
savsge Abyssiniant are said to do to their cattle, — 
a cruelty which the inferior animals, and even civil- 
ized man, inflict most unmercifully upon vegetables 
— if it he true tlist vegetablea fe*I — in the many 
mowings of the green Iswn, in the perpetual bite or 
browbing of the tender herbage, in the pruning and 
naihng of the annual shoot, and in the periodical 
clippings or loppingB of shrubs or of trees. It is 
rather by a destruction that is prompt and sudden 
that man assails his victim, extinguishing life and 
causing death in an instant ; and it is certain thst 
an animal can suffer death but once, though s plant, 
upon this supposition, might have many deaths to 
suffer. As It is, we have a sort of instinctive ap- 
prehension that plants do not feel, and henee we cut 
and chop them up without mercy. Hence also the 
mower whctb his scythe, and the reiper his sickle, 
and the woodman his nir, without experiencing any 
emotions whether of sympathy or of sorrow; and 
hence we can bear to witness or to conteroplste the 
haroc thst is annually committed in the meadow or 
in the corn-field, or in the wood or forest, without 
having our feelings outraged or our sympathirs ex- 
cited; though wc cannot hear tither to witness or 
to contemplate the pains and sorrows of suffering 
animals, but with the tear of sympathy or Ihe cry 
of commiseration. 

From tho above premisci it follows irresistibly, 
that plants, though exhibiting indubitiihle indications 
of such tis^nnl and organic susceptibilities as are 
proper to ihcir rank in the scale of being, do not, 
after all, exhibit any satisfactory indirations of the 
sensible or voluntary siiflceptibihcies of animals, and 
do not, in fnrt, cither feel, or will, or desire, or de- 
sign. T^ie movrnients which they display are sin. 
{uUr, indeed, and surprising, but they arc not sttch 
OS evince any legitimate evidence whether of sensa- 
tion or of intellection. These are attributes that 
reside only in animals, and that reach their higheat 
degree only in man. 



MANUFACTURE OP CHAINS. 

At what period, or under what circtimatane*^, lAs 
manufacture of the common kinds of useful dmas 
commenced in this country, we cannot atfCVBotaly 
determine. Our cxiuntrymen have long boM rt> 
Downed abroad for the fabrication of curious diaiaik 
or strings of twisted wire, (o which watches, 
cases, and trinkets in general used to be attt| 
These articles were prized and Imitated by toMigotn 
as the English chain. Of late years, and in ttrina 
countries, an endless variety of fancy UaVan^ 
made of different kinds of wire, have Bi)C««Mr«e)| 
made their appearance, the cnumcrwlion or deaeri^ 
tion of which would be almost as difficnltt at ta 
general an amateur attempt to imitate the cKsr 
themaelves would be unsucotrsafa]. 

Perhaps one of the simplest and almost [ 
weakest forms of chains is that, the link^ of ■!< 
are composed by bending a bit of wire iuio k «> 
of loop at one end, aaid bending the other ttul n 
tike manner, only that the loops make right a»«l • 
with one another. Thk ii the broio chain vstn 



connected with the smaller scales in retail ah. 
.Made stronger, and of iron, it ia used for 
heavier articles, and as a dog-ctiain. It i 
different from another well-known choib, iiic 



composing the links of which is hooked or twiatri 
at the ends, to give the greater strength. It % 
however, both less neat and leas stroog than tkt 
links which are mode of coils of wire. 



together in the middle, and then wrapped 
with tlte wire. The next figorea are chaina 
wire : they ore both of ooiuiderable antiquity- 




In the manufacture of chaina for almoct aff ft^ 
orrlinary purposes to which they are no- 
tlie links are either pieces of wire simplv 
the desired form, and the ends of the mi 
brought into such contact with the shank or 

each other, that they ntaintain their < 

thry are soldered together; or, 1- 
welded in the ujiual manner of ui>. ^ , 
iron. 

Instead of forging the material for the llnk^ flVt 
of a light bar of square iron, ai wis thr 
formerly, the general course is to uoe r< 
which is reduced exactly to the sise m|utmi oj 
being passed through grooved rnllcn. 1^ v«A* 
man VtV^tt a rod of this iron, heats it in his hi«t& 



^ 



MAGA2INE OF SCIENCE. 



285 



» cherry rrd, and Ihen withdrawing it, be placet 

opoa ■ chiwl. and roeatqrinK the length requisite 

Kovm a Unk. gives it a itroke with hii bftinmtrr, 

beods it Into the ahape of a u. Then taking 

i of ihiH half-fonned link with his tonga, he 

it again in the fire ; and having brouijht both 

to a welding beat, he unites them by ham- 

ig on the beak or point of his anvil, taking up, 

Mine, aa he proceeds, in tyery caae the link 

bik faraed, which, for the convenience of catching 

„..:- 1.^ hangs upon the beak or point of bii 

le he heats and bcnda the iron for the 

; and lo in lucceiiion with each, until 

be of the length required. The dexterity 

>h{eh a clever workman perform thia procesa 

ig common light cbainii, can onlj be con- 

f angbc by thoae who have either witnessed 

'oraome similar manufacture. 

oat common form of the link In chaina for 
purposes is that of an uval, the stress 
of coune, always In the direction of ita 
aaia ; this form, however, is varied according 
BtBStaiiees, and as lightness or strength be- 
indispens^Ie. In the former case, aa for 
the links are generally made considerably 
whereas In crane and similar chains, the 
rm ii contracted in length as much as is 
klevrith the free motion of the links in each 
Jt must be obvious that in common cbaiDS, 
•re continually in use, the principal wear 
on the inner surface of the extremities, where 
In an in contact, and with considerable motion 
c chain is in use; and hence it was no un- 
Ihing to see cart traces worn quite through 
ids. while the sides wrre nesrly aa stout aa 
It made. To rrmedy this c\ il, a very simple 
WM made; the link, instead of being of 
■tthataoce, as heretofore, was mnde thicker 
ettramity of the oval, and thus the dura- 
tkm chain was indefinitely increased. As, 
this method added much to the labour and 
tt expense of the article so made, when 
it by the hammer in the ordinary manner, 
Hawks, Q metropolitiin iron master, who in. 
this improvement, obtained a patnit Tor 
iag cbaioa of this deacription out of iron 
into the proper form by being passed through 
the groovet in which were deeper and shal- 
vt distances answering to the circumference 
bnk ; ao that the maker had merely, as in the 
'.€i round rods, to cut off snd weld the links in 
manner. These knatted chains, as they 
I, are now made by ail the chain-makers. 
TkM bcaviot traces, and they are generally of the 
^fost described, — are those used with the Lon- 
i4ri7-hnr«cs ; the next sort by the SulTolk and 
■~. for plough traces; and a still 
k-d the Edinburgh traces, are used 
.^cotrn. The Yorkshire traces are mostly 
links of the ordinary kind, made out of 
round iron. Cart traces are generally 
feet in length, and weigh, according to the 
from ten pounds to eighteen pounds p<^r 
Haltar-chains, thoae used with bridles, and 
teeone<?trd with horses used in husbandry, have 
^t twisted, for which no particular 
]•: fancy of the parties, seems to be 
bsoi*'. 1 rie " hack-band," as the carters de- 
lta tlie chttin which, pasaing ov<^r the saddle of 
korae. supporta the ehafti of the vehicle, and 
illy the load, is always twisted, and made Hat and 
e : a b composed of a double scries of linkst 



the whole being, when united, heated in the fire; 
and after being twisted through the entire length, 
it la hammered into the square form on the anvil. 
Ropes hare given way tu chains lets generally in 
the working of pita than where both are used for 
most other purposes. The reason la, that the chain 
is supposed to break without giving warning, whereas 
the wenr and faults of the rope are generally noticed 
in time to forestall the danger. Beneath are chains 
used in collieries : tha last of these is s sort of metal 




rope* intended to snswer the porpoaea of a hempen 
rope in the working of mines ; also for wells and 
cranes. Ic was first made in 1790, by Mr. W. 
Hancock, of Bingham, near Nottingham, and a 
premium of fifty gnineas was presented to him for 
his invention. It is made of wire three-eighths of 
an inch thick, twisted into coils. The firat of these 
on the smallest acsle representi the chain found ia 
the inside of a common watch. The next cut shows 
a bar chain, similar in principle to it ; it was, in 



^ 



1805. the patent right of WiUIam Hawks, a Dur- 
ham iron manufacturer, whose invention consisted 
in making chains by cutting the linka out of a flat 
bar by means of a fly press and proper diea, and 
then fitting into tlie holes bashes or thimbles to 
give them greater strength. A few years afterwards 
another patent was granted to a StalTordshiru iron- 
master, of the name of Smith, for producing links 
of a similar form by means of rollers. 

Latterly, the use of ropes has been Isrgely super- 
seded by Uie adaptation of cbainii. not merely for 
cranes, hauling purposes, &c., but especially for 
cables ; large manufactoriea for chains of thia des- 
cription having been eatablished in London, Liver- 
pool, Hull, Bristol, and other ports. The use of 
the best material for this purpose had become so 
importiint to the slupping interests, that when, In 
lH2Cf, Mr. Huskiaeon proposed tn parliament, a 
reduction of the import duty on foreign Iron, he 
laid especial stress on ita tndis|>cnsability In the 
manufacture of iron cables, which had of late come 
into very general use In our ships. The honorable 
gentlemaa observed, that "a mixture of Swedish 
iron waa considered of great advantage ; and those 
cables in which It was used were considered best. 
Here, then, (argued the speaker), a most important 
benefit to our naval interests might be counteracted 
or prevented, by continuing the present high duties; 
the reduction of the duty on this article was oa 
every account desirable." 

(Tobeamiinwti.) 




28G 



MAGAZINE OF SCIENCE. 



SHOWERS OF FLESQ AND BLOOD. 

SoHR literanr work kt NasbWIle, ciillfd the " Bui> 
ner." in tlie 8ute of Tcntr»ce, in ikc Uniteil Sutea, 
hss a Cerrific arUcle under the above frighlful bead- 
ing, exciting a more staring woodpntient in the 
iiaUvcs there, than the blood; or " ted mou*" did 
in a recent skctcii uf the Arctic re^ons, which latter 
wonder waa accounted for by the most eimplc and 
naturul means. 

Su have the " ahowerf of blood/' 0cc. been ex- 
(ilnincd away by a neighbour at Alexandria, at the. 
larvK of ioMctit, particiUarly the species lAejndoptera 
(buttcrfHes). 

Wc will for a moment pat the shower of " flesh" 
on one side, that being only the jfontiMh of the dihh 
of horrors. 

There is a proli5c species of the bvtterfly on Urge 
contineota, wtiich, when they emerge from the pupa 
or chrysalis atate, discharge a reddish tloid ; and 
where they are found in great numbers, a consider- 
able extent of ground may have these red spots, 
exhibiting the appearance of the trarea of a night 
shower. This is no recent discovery. Sleidan, as 
fmx back as Ifjolt, deftcribes a multitude ofbatterniea 
which swarmed through a grcit part of Gcrmahy, 
sprinkling plants, leaves, &c. &r. witli bloody 
drops, as if it had rained blood. Ueaumur gives a 
further notice of it, aa occurring in the suburbs of 
Aix, in 1G08, when a wide breadth of Und was 
sprinkled in the same munner. A ** grc't aenaa- 
tioB** was the first consequence, till a Mr, Pierese, 
B philosopher of the vicinity, explained the true 
natare of the phenomenon : a chrysalis, which he 
had preserved in his cabinet, disclosed the secret. 
UearJDg the fluttering of the insect, when it had 
arrived at its mature state, he repaired to the spot ; 
he opened the box, and the aDimoJ flew out, leaving 
a red spot behind it. lie compared this with other 
of the ** bloody shower,*' and found them exactly 
alike ; but in this latter case, at Aix, the spots were 
chiefly found in comers and cavities, where rain 
could not very convenientty come, and in such 
pUces aa the insects sought aa a refuge. But a 
very little doea with which to start a good story of 
this sort. 

Those who may wish for further information on 
this subject, in connexion with the amusing history 
of that bappy fluttering and changeful btiiig of the 
winter's death and the aammer'a reeurrtction, with 
■ngeU* wings into sunny skies — the butterfly, — may 
consult Comstock's " Physiology,^' and No. 74 of 
the *' Family Library.*' 

The "flesh" alluded to in the Nashville story, 
in order to render the monstrosities en tuiie, was 
most likely a part or portion of some inBcctt that 
perished in the process of transformation. 

AUCHINE FOR DRIVING PILES. 
A MACitiNK for driving a double row of piles, which 
waa coostructed at Utica, in the United States, and 
recently brought over to this country, is now in 
operation at Smith's timber wharf, Pedlar's Acre, 
where it can be seen driving the piles for the cause- 
wfly and abutment on the Surrey side of the New 
fluDgerford Market Bhdge. now in progress. The 
hammers, or weights, or as they are more usually 
called by the pile-drivers " the monkeys,'' are ele- 
vated to a height of thirty-five feet or thereabouts. 
along grooves in perpendicular leaders, by means of 
t locoffioCire iteam engine of tcD>hor:ie power, fixed. 



on a platform, on which the whole of the nuchiacff 
i« placed. The power of the blow given by mA vf 
these hammers excectti six fanndred tons, and drmt 
a pile of twenty-fieven feet long, and us thick aatiM 
thickest piles used in embankments aud for coAer* 
dams, nearly its whole lenj^th into the earth, la aboHl 
eight minutes, or perhaps less. It drivea two fiim 
at the same time. A circular horiaootal saw it 
worked by the engine, which, in a fcwseroods, can 
the tops of the piles even, and enables the trucka> 
or email wbef la on which the platform ia aupp 
to came forward as fjiat as the piles are dri 
cat them even at the top ; the platform U pi 
by a one-horse power by the engine. The poww 
this machine is astonishing, and rcifuirea to be 
to be fully estimated. It isao imfiortant applieatMn 
of steam power. Itkely to produce very h efng t ria l 
results in public works, ia the formatioa «f tm 
banks, and in all operatious on a large acale whmti 
rapidity of execution and preciiion are r^nirttfi 
The macliiue wos used in America for driving pilfl 
fur rail-roaila; and Cravellrd by its own po«cr n^ 
wards of two hundred milei, driving pilea. M 
making itfi own road through swamps and disliMit 
heretofore impervious. It i> patented in this covaUft 
and also in the United States. The machine hu, 
moreover, the power of drawing piles out o/ the 
earth as quickly as it drivea them in, and c«d H 
applied to the raising of blocks of stones, and sO 
heavy weights that require an ojitraordinary pow«b 
— TYwiet. 



t \r^^>^-*^-.nitr ^^f / 



BIRDS, 

IN aErEAENCIf TO 0ARDKX9. 

DiRDS are, upon the whole, murh more beneMil 
than injunons to gardens ; and being also U>|<C 
auimals and more familiar to every perwn living ti 
the country than insects, very little requires to bs 
said respecting them. We shall briefly nc>ticv tirt 
commooeat EngU«h birds of the diffei-cat order*} 
taking aa our guide Jenyna' ManuAi t^ MnhA 
Vertebrate Animalv. 

Raptiires {Seiiers.) — Birds with feet formed far 
grasping : food, entirely animal auhktaocrs. Ttdl 
Older includes the eagle and falcon, which may bl 
considered injurious to gardens hy acanng a^ 
other birds which are useful. Ic alto includei tbi 
sparrow. hawk, which prt-ys upon the ainaller birdi 
and quadrupeds, and also on amphibise ; on whtflk 
account it may be ooasidered aa partly injurioai aod 
partly useful. This may aloo be aaid of the ktl* 
The kcstril, or wind-hover hawk is peculiarly Tahlf 
able for killing beetles, and it also destroys 
and snails. It is peculiarly fit for a garden, becnavj 
cats dare not venture to attack it. The white oiili 
or barn-owl, with tawny yellow plamagr, wUUj 
anderneatb, ia one of the most valuable btrds eli 
this order, becsnse It feeds principally upon 
snaila, aud Uugs, and occaaiouoUy deroura 
small animals, such as rats, aod aomctit 
rarely, fish. It is common in every part of 
kingdom ; it comes abroad about aun«et, and oo 
its food during the night. It may be known 
the tawny owl or wood-owl by ecreamiog in ttt^ 
flight, hut never hooting like that specie*, 
this useful bird caught its food b> day." Mr.Watcf-; 
ton observes, *' instead of hunting '•"" •' I'v uitHl 
mankind would htive ocular dvnn 
utility in tliinning tlie country of i>>: 
be protected and encouraged every Mhevv. it MwtUdi 
be with us what the ibu woa with the Kgypl 



MAGAZINE OF SCIENCE, 



cftf K^ 



U hu Touzifr, It will bring i mouM to the 
•bcmC mretj twelTC or fifteen mmutc*. Bat in 
U> li»vo K proper idea of the enormouji quantity 
•f mrw wliirh thti bird destroys, we miut exninine 
thf prjkpij vt bir}i it fjert» from its stomitch in the 
■Abbt ot iu rctr«iil. Every pellet contjiitift from 
ma to •€¥«» fkeletoa* of mice. In itxtcen months 
iron tkm Hm9 that the spiirtnient of the owl on the 
•4A ps«««y at W«Jioq HkU was clesned out. there 
Im bctfts ft deposit of above a boshel of pellets." 
IW tawny owl, with reddish brown plutnmage, is 
only in woods, where it builds in the hollows 
Aid trop«, or amon^C ivy. U preys upon various 
cf«md[n|ieds and birds ; it comei abroad only 
th« ni^l>t| and has a clamorous and hooting 
By deafroying small birds, this owl becomes 
to the gardener u well as useful, and 
heoufhl ckiftly to encourage the barn-uivL 
purpose a pictunrsquo tower might be 

- —' retired situation in the flower-garden 
on one of the angles of the kitchen- 

. <ke a watch-towi^r, where it would 

omaoMBtal ; and a brood of young owls 

brought to it, and snpplied abundantly 

- till they were full-erown, and able to 
r themselves. Tiie time to procure the 

Difds i« abont the end of April ; or the e;;gs 

I procored tad hatched in the bark-bed of 

i, flkc. There are lome other aperies of owl 

ilJy found in England, but they are too rare 

Lof any practical use. 

^res t^Perehen). — Birds with feet adapted 

Ing : food, chiefly insects snd the smaller 

ipeds, but partly fruiUi and seeds. This order 

a number of birds which are interesting to 

The shrikes, of which there are two 

.fred on email birds, mice, snails, and insects. 

r-aatebera feed on insects taken on the wing ; 

these the caltiTated or hive-bee does not 

The water oaict feeds on aquatio insects, 

oipablc of diving for them. The missel. 

ttw on insects snd berries, particularly on 

«f the miatletoe. The field-fare feeds on haws 

berries, and also on insects and worms. 

|.thniaU /eeds on berries, insects, and snaiU; 

the blackbird and the rerlfrin;. The rcd- 

cm Insects and worm« ; and nl»o. when 

•can:«, on seeds or crumbs of bread. 

Uvea chiefly on insects ; the wag-tail 

Meis. The titmonae lives chiefly on 

also eat seeds. The greater tit- 

tord pressed for food, livps npon the 

; aad, sccording to Mr. Muin, sometimes 

great numbers of them. The bird *' seats 

at lh« door of the hive, and taps with his 

proToke the bees to come forth. The first 

B«s out is instantly seized by the middle 

off to a tree, and there beaten against 

till it is nearly dead. The bird then se- 

the l»ead and thorax, which it swallovrs, 

•Mosnen, whiiib it rejects, as containing 

Msd then flies back for another victim." 

titmotise, an inhabitant o( fenny dia. 

on snails and other land raolluscv. The 

Is «li inaecta and small seeds. The Ctrl 

in Derooahire and some of the sd- 

s, is aaid to feed on the berries of tho 

Dalcamva. The chafliDch, the hou5e- 

r, IIm trer-sparrow, and different other species 

19 (o tk« genus Pringilla, feed on insects and 

on berries; and when food is 

of treea. They nln ett the 



long 

1 



anthers of eroeusrt and other spring flowers, la 
severe winters the buds of tlie gooseberry and cur- 
rant tribe are sometimea devoured by the common 
house-sparrow ; and this even in the neighbourhood 
of London, where it might be supposed this bird 
would find food at all seasons. The bulllincb, cfoaa> 
bill, and starUng, lire on ioaeols and worms, and 
occssionally grain. The raven lives on mice, rats, 
poultry and other animalsi as well as on carrion. 
The carrion crow and the hooded crow have similar 
habits. Mr. Waterton considera the carrion crow 
as merely a variety of the nven ; " lie rises long 
before the rook, and retires to rest later than 
bird. Indeed, he is the hrst bird on wing in 
morning, and the last at night, of all our non 
gratory, diurnal British birds. He feeds vorncioui 
on ripe cherries, and in autumn eata walnuts 
he de:*troys many worms and caterpillars ; though' 
when his young arc in the nest, he seizes game and 
young poaltry wherever he can find them." The 
rook lives principally on the grub of the cockchafer, 
the wiri*worm, and other insects ; but will occasion- 
ally devour corn ; and, during the winter season, la 
very destructive to turnips. The jackdaw, the jay, 
and the magpie, feed on a great variety of aniwal 
and vegetable substances. The woodpeckerof which 
there are s^fvernl species, feeds on ants and other 
insects; more e4t**^cia11y on the larva of the timber- 
eating species, which it extracts by means nf Ita 
long tongue, aficr having perforated the wood with its 
bill. " Neither the titmouse nor the woodpecker," 
Mr. Waterton observes, " ever bore into the hard and 
live wood." The wryneck lives principally on aatit; 
and the common creeper which la generally dispersed 
through the country, and is remarkable for the great 
fucility with which it climbs up the trunks of trees, 
feeds entirely on insects. The nuthatch lives oc- 
casionally on insects, bat principally on nuts ; which 
it breaks with its bill after baring lirnily fixed them 
in the crevices of old trees. The cuckoo fceda 
principally on caterpillars and other insects. The 
swallow and the martin feed entirely on insects taken 
00 the wing ; they sppear abont the end of April or 
beginning of May, and depart in October. Tho 
gostsucker lives on insects, particalarly on cock- 
chafers, which it seixea on the wing, and on butter- 
flies ; but this bird is n\ore frequently fonnd in solitary 
woods than in gardens or frequented places. 

The greater number of birds which frequent gar- 
dens belong to this order : and while they do good 
by devouring insects, snails, and worms, they are 
also to a crrtain extent injurious, by eating fruits 
and attacking newly-suwn or germinating seeds. 
The singing- birds are the best for destroying sofV- 
winged insects, such as moths and butterflies. Of 
all the birds of this order, perhaps the bodgu-spnr- 
row is the mo«t horroles*. and the housc-spsrrow the 
most mischievous. The former lives upon the seeds 
of weeds or other plants tbst lie upon the surface of 
the ground, and it rarely attacks buds ; while the 
house-sparrow acrntches up newly-sown seeds and 
crnpe the tops of seedling planta when they are just 
penetrating through the surface of the soil, such 
peas : it also eats the smaller frulti, and, when o 
food is wanting, attacks buds. The robin devo 
currants, more especially about the time the young 
robins leave the neat, in June, when the carrants are 
beginning to ripen. Hlackcaps, whitethroats, snd 
balltioches. eat curmuta, strawberries, and raspbtr- 
ries ; and of the latter fruit, bullfinches are pard- 
cuUrly fond. Gooseberries, being too large for the 
soft-billed birdie ba sooa as they ripea aro 



omB 



B Attacked 



S88 



MAGAZINE OF SCIENCE. 



bj blsckbinls and tbnisbei ; and tfae foadarn of 
tbcM birds for ripe cherrien has long been notorioai. 
Tbe wren and the llf-catcher are purely insectiTo- 
roua ; and the tomtits, though they ftometimea destroy 
builtt, yet arti fnr more usefol ihan iojuHoua. from 
the Domber uf caterpillars which tbey devour. 

Btuitrft {Seratt^Mert). — Birda with feet not formed 
for acraptng : food, chiefly seeds and terrestrial ver- 
niu. The ringdove, and different other species of 
dovea, live on all kinds of grain and aecds, and, 
during severe weather, on the leaves of turnips and 
other cultivated plants ; and some of them occa- 
sionally eat tbe smaller snails and slugs. Tbia is 
tbe case with tbe domestic pigeon ; though it more 
frequently lives on peas and grain. The turkey 
Uvea on snails, slugs, worms, lizards, frogi, and 
terrestrial iosecta, together with com and seeda of 
almost every other kind. Tbe peacock lives on 
stmilar food, and will even attack amall snakes. 
The Guinea pintado, tbe domestic cock, and the 
pheasant, are omoivorona, eating roots as well aa 
mnimaU, fruits, and seeds. Tbe com of Kanunenlos 
bulbftsus, where it abounds, is greedily eaten by the 

Eheasant. The gronse frequents woods of pines, 
trch, ind juniper, and feeds on tbe berries of the 
latter, and on tbe buds and tender spray of the two 
former. The black groase feeds on berries, and on 
tbe tops of henth and birrh. Tbe common partridge 
feeds on seeds and insects, and especially on the 
pup» of ants. Few of these birds concern the 
gardener, except the turkey, peacock, and pheasant, 
which may be useful in pleasure-grounds io picking 
up vermin. 

MEMORANDA. 

The Common ll'atch, it ii said, beats or ticks 
17.100 times in au hour. This is 411,140 a day, 
and 150,424,560 a year, allowing tbe year to be 
365 days and six boars. Sometimes watches will 
run, with care, lOU years. In that case it would 
last to beat 15,042,456.000 times I 

putridity of yfeat. — Until tbe experimenti of 
tbe celebrated Italian jihysician, Redi, who died iu 
1697. inaecta were supposed to be engendered in * 
putridity, and not by their own species. Tbe cor- 
rection of this error Urst led butchers and houae- 
kcepera to guard meats from flies, by defending 
them with gauze coverings. Tbe must intporLant 
of Redt's expcrimpjits was the following : — He put 
some meat and lish into a large vessel, covered with 
Tery fine gauze, which he also put into a large box, 
covered with the same gauze, that the air might 
penetrate to the raeata while it remained free from 
tbe intmsion of insecta. On these be did not see 
a single worm, but frequently saw the little crea- 
tures writhing about on tbe outer gauze, trying to 
make tbcir way through ; and it was with difficulty 
tliat he was once quick enough to prevent two of 
them from falling on the mrnt, for they Imd gut 
their bodies half through the inner gauze. Ik- abo 
observed tbe flies, attracted by tbe meat and unable 
to make their way to it, drop their eggs upon the 
ginze ; some of tliem alighting upon it. others 
hovering in tbe air during tbe operation ; and he 
perceived that each left six or seven eggs at a time. 
This was tbe point he wished to ascertain ; and he 
had now discovered that insects snpposrti to be en- 
gendered by corruption were, in reality, propagated 
by their own species. Daring tbe coume of these 



experiments, Redi ascertained the 
when tbe common day-fly dies, it 
for its own species equally with any 
dead flfdh. 

Draft in CkimneyM.—V^tn a fire is Ugbt 
atove-gratr, the air in the chimney orer it 
bested by the 6re, and therefore lighter 
external atmosphere, and cousoqoeDtly it 
Thus ia produced nbat is c^led s drift in Umi 
ney, which la merely the upward current of i 
dnccd by the ascent of the heatrd air conj 
the flue. When a grate has remained for 
time vrithout having a 6re in it, tbe chimney, 
/kc. become cold, and when the fire is first 
does nut beat the air fast enough to produce a <whj 
rent necessary for tbe draft : and as the sine 
not ascend, it issues into the apartment, 
feet is often attributed to tbe supposed fist 
the chimney, instead of the abore cause ; fat\ 
the grat£ and flue become warm, the dnafk 
stored, and the chimney ceaaea to smoke. 

Duratniity of Brickt. — An impreaaioa eiii%, 
reference to the want of durability in bricks*,) 
building material, of tlie correctness of wbicb . 
reflection will convince us there is acme 
vided tbey be properly made. So far from 
the most perishable, they are tbe moat danbtci 
stance ; and the bricks of Nineveh and Babytoa, 
the muneums, show that they were selected by tfet i 
ancients sa the moat lasting material. Plotsrcbl 
thinks them superior in durability to stooe, If pRK 
perly preps red ; and it is admitted that ttel 
of Caracalla, thoae of Titus, and tbe Thoraft 
Diocleaian^ have witbatnod the ciTects of time 
fire better than the stone of tbe Coliieom, or 
marble of the Forum of Trajan : yet tbe bricks ' 
Nineveh and Uabylon (and some of thoae of 
Humans also} were only sun-dried — not bakei ^1 
burned, as tbe modem practice is. 

Organic Remain*. — An interesting diacoverylMi 
recently been made in Mr. Brewer'a qnury, bi 
Boxflcld, Box, of fossil bones, which were fonail ia 
B cavern, seventy feet under the surface, and bsfi 
the same appearance as the freestone, or oolite, tstt 
are much lighter ; tbey are numerous, and 
them the vertebra are very distinct, and 
bones like legs, and a bead, but there is notbi 
indicate thai they belong to any existti^ 
Nothing of tbe kind has ever before beat foiml !■< 
the locality, nor in cutting tbe Box tunn- : 
specimens of vegetables and lisfa have bee- 
the inferior oolite, and the clay oo wbtLa 
recumbent. 

A. vessel has been constructed by a comj 
Ijouisania, to be propellt*d by carbonic acid 
the principle discovered by Tellerien and Pi 
the acid being generated in a liquid state, 
great pressure. The invention consists in 
two large gu generator, on the same plan i 
of Tellerin, which are supplie-d with seaqui- 
of soda and sulphuric acid. A few drops 
liquid carbonic acid produced by the mixture of tba* 
KubKtances are allowed to drop alttrrnately bdon 
and behind tbe pistund of an engine, conUindtib 
those of a steam engine, and at this liquid aod if <t 
a prcsKure, of at Irast *J5 atmoaphefea, its grsit 
expansion gives motion to the engine. By tbUnaapi* 
of propelling ships, a few tuns of scsqai-carbonils 
of soda and sulphuric arid, would be anAcient fat i 
voyage acroii the Atlantic. — Lt Famnt. 



Lardom— Pnotad by D. raAwcit. 6, Whtto Hon* Una. UUa Cad^-Publlahed by W. IlRiTt*m. ll.PatMmM*f R«W- 
CtfBioiunieaUou. (whioh are ansivtrcd lloothly j le b« adOrriaed to tbe Editor, at 37, Cottuee Crov«, Ictle E^ Aaii 




wm Ibc xDtmt ocratidermMc, (rf* 1» 
md bom the •Imooi taHMiAii 
A it iitended. Tha feOvnic « 
Gilbert's Annaln, 1019. 
the Mooad Toinaa cif 



r oatviett the raf^ 
a< UovbC PiUtas wen 

wUit-h were poviOallii 
viibonl being of tlw leMft 
who had beok om^ 
in the ponoit of i^ 
of several Si 
rity of th« timhm. IWi 
however, oomidcnd h q«lt J 
■ffiQ ihaaMlvfla of 
a mC KiU U» cad of 1816. tM 



*rr^ 



ar 1^ ^vlfaartoft af 
il : Md Aa tnWhiliMli atafl ihcowtvca ol 

itiB rntr<» of (ravlty l» 

tJuH iif this Ubour. 

^ Of all Iboae ipecimeaa of cvpcatv?, the Shdc of 



a certoia atf 

the cooatnif't"" «' 
in theapriii^ 
K«f Alpnach u fonD^' 
fiat trees, depriTed ol tl>' 
ia ■ very LngiMiioDi iDKn. 
mi ^ craa. It occajiied uhout 160 

■mtithn, and eost oeariy !< 
« OMf. It ia abouc three 
k^M fat lo«v. and tcnniiMtea I 
h hia the form of a troof K 
id fram three to aix fe<^ 
of three trees, the n i 
a u — wt cat OQt in the dire^wa at 

asuU rilU of water. 
MM k fron TKrioufl pIeoea« for th 
tf Aani^faf the friction. The whoU 
by aboal 2.000 supporia; 
. in a T 
pndpioea of fraoice. 
af the tUde is aomctiowa 
with an inclination 
1^ » lif . h ii aAca carried aloaj; th* 

of pROpitoui rocks. And •oar 
•air Ihair mnmica. Oc< 
at other time < 

mi 0mt Iha deep gOftM bj scaH. ^, .^ 

m hai|ht. 

Tha Wdaaat which characterixea tUa anrh, 1 
•Mi akil dufdajed in all ita arraapi 
of every Penon aha 
^ Babn any itep could be taLaa tp 
f to cot several 
a paaw^e throngh the tm| 

diAcoltiea, however, wtra 
•ad Ac cafineer bad at Uiit ibc ulii 
^a toaea dcaceod frum the mountiia 

a/ lifhtoiof . The Urg(>r y>uc^*. wK-k' 
:a hai^iad feet long, and ten 
V cxtremtty, raa tbrough 
or Bcarlj ame «a/e«, m fH'-> miinttt 
m^ m ka0', Md dariac thoir deacent. ihejr «p| 

ti ha aatr a few feet io length. The nr-^-. 

ftr lUa part af the operation were extr<- r 
end of the slide to thr 
■ Wn fha treca were introduced, woHcmeo 
poated al r^^nlar dittneei. and a« aoon aa 
lkia( waa trndy, the workman at the lower i 
iW altdc €r»eA ont to the one above htntt " /<«eAcf*' 
(t«l go). The cry was repeated froiai one to in^^ 
and rratrbnl the top of the slide in Mr«r< 
Tne workmen it the top nf tS' -'■•>'■ lu'^ 
cfied oat to the one below bim, *' /. 
oooea). and (he tree nu iaitiatly Un^ 



MAGAZINE OF SCIENCE:. 



tIMc, prercded by Ihe cry which wm repeated 
|Hnt to pott. A« sr>on ni the tree bad reached 
bottom* ind planed into the lake, the cry of 
tXfs wu repeated ai before, and a new tree ff«a 
:hed in i similar manner. Ry thef^e means a tree 
^Miadrd every Ate or lix rninateft, proviJed no acci- 
^^^Hlippened to the ilicle, which aometiinea took 
^H|Bwil whieh was Instantly repaired when it did. 
^V^W order to ahow the enomiotu force which the 
^P»M orqnirrd from the great velocity of th«ir de- 
PbcDti M. Rupp mnde arrangements for causing ftnme 
of the tree* to Fprinj^ from the slide. They pene- 
ted by their thickest extremities no leas than from 
to twenty-four feet into the earth ; and 
rf the tree* having by accidrnt strack against 
ler, it instantly cleft it throuffh itswhole length, 
it had been rtmck by lightning^. 
Aftrr the tree* had drucfndfd the alidr, they 
collected into rafts upon the lake, and ron- 
lo Lucerne. From thence they descended 
tts, then the Aar to near Bmgg, afterwards 
iWildifant by the Rhine, then to Baale, and eren 
the «ea when it was nvceasary. 
It ia to be regretted that this magnificent atmc- 
BO longer exists, and that scarcely a trace of it 
be seen npon the flanks of Mount I'iUnis. 
circanittanRes having taken away the prin- 
irer of demand for the timber, and no other 
ing been found, the operation of cutting 
trtiag the trees necesaarily ceased/* 



rvfracti 



ATMOSPHERIC REFRACTION AND 

REFLECTION. 

f^mumtdfrnm page XM. ami cvnelmM.j 

J Mngnlar appearances occur from the 
txpuifion or condensation of the strata 
in contignoMs to the surface of the 
which distant objects, instead of being 
tre depressed. Sometimes, being at once 
Ited and depressed, they apprar double, 
isuiges being direct, and the other in - 
In consequence of the upper edges of the 
nmon being Icsi rrfractfd than thfr tower, 
■ppear to be oval when near the horizon, 
also, or elevation of coasts, mountains, 
rhen viewed across the sea, ariMji from 
tion. Single and double images of 
aea, arising from sudden changes of tem- 
i, which are not ao soon cororounicati-d to 
on account of its density as to the air, 
E rarely, and are of shorter duratiim than 
mfptmnocet on land. In 1818, Captain 
f« whoae obaervations on tbe phenomena of 
are so valuable, recognized his father's 
inverted imag« in the air, although the 
was below the horizon. He afterwards 
■he was seventeen miles beyond the 
d thirty miles distant. Two images nre 
seen suspended in the air over a ship, 
and the other inverted, with their tnp- 
bulls meeting, according as the in* 
ia above or below tbe direct image. 
}Q has proved that these appearances are 
the refraction of the rays through media of 
denatties, by the very simple erperimcnt 
If along a red hot poker at a distant object, 
are seen, one direct and another in- 
d, la conwqutnce of the change induntd by 
leat in the density of the adjacent air. He 
■*ftd tbe same effect by a saline or sBcchnrine 
too with waier and spirit of wine ttoatiog vpoa il. 



tfceir 



Many of the phenomena that have been ascribed 
to extraordinary refraction seem to be occasioi>e4 
by a partial or total reflection of the rays of Ught 
at the surfaces of strata of difl^rent densiliea. It 
ia well known, that when light falls obliquely upon 
the external surface of ■ transparent roediam, as oa 
a plate of glass, or stratum of air, one portion ii 
reflected and the other transmitted. But when UghC 
falls very obliquely upon tbe internal surface, the 
whole i* reflected and not s ray ia transmitted, la 
all esses tbe angles made by the incident nnd reflected 
rays with a perpendicular to the surface being equal. 
As the brightness nf the reflected image dependa 
on the quantity of light, those arising from total 
reflection niast be by far tbe most vivid. The de* 
lusive appearance of water, so well known to Afri- 
can travellers, and to the Arab of the desert, aa tbo 
l^ke of the Gazelles, is aacribed to the reflection 
which takes place between strata of air of differenc 
densities, owiog to radiation of heat from the arid 
sandy plains. Tbe mirage described by Captain 
Mundy. in his Journal of a " Tour in India," pro- 
bably arises from this cauae. " A deep precipitouB 
ToUey below us, at the bottom of which I had seen 
one or two miserable villages in the morning, bore 
in the evening a complete resemblance to a bttotifiil 
lake ; the vapour, which played the part of watWr 
ascending nearly half way up the sides of tbe vale, 
and on its bright snrfare trees and rocka being 
distinctly reflected. I had not been long contem- 
plating the phenomenon, before a sudden storm 
came on uid dropped a ctutain of donda over the 
scene," 

An occurrence which happened on the 18th of 
November, 1804, was probably produced by reflec- 
tion. Ur. Bachan, while watching the rising sua 
from the cliff* about a mile to the east of Brighton, 
at the instant tbe solar disc emerged f^om the nr- 
face of tbe ocean, saw the cliff on which he waa 
standing, a windmill, his own figure, and that of m 
friend, depicted immediately opposite to bim on tho 
sea. This appearance lasted about ten minutes, till 
the sun bad risen nearly his own diameter above 
the tiurface of the waves. The whole then scemeil 
to be elevated into the air and auccesaiveiy vanished. 
The rays of the sun fell upon the cliff at an inci- 
dence of 73'^ from the pcrjiendirolar, and the see 
was covered with a dense fog many yards in height, 
which gradually receded before tbe rising sun. 
When eitraordinary refraction takes place laterally, 
the strata of variable density are perpendicular to 
tbe horijon, and if combined with vertical refrac- 
tion, the objeeta are magnified as when seen through 
a telescope. From this cause, on the 26th of July, 
179H, the cliffs of Prance, lifiy miles olf, were aeea 
as distinctly from Hafttings as if they had been cloM 
at hand ; and even Dieppe waa said to have boflO 
visible in the afternoon. 

The stratum of air in the horizon ia so mnch 
thicker and more dense than the stratom in the 
vertical, that the sun's light is dimiaisbed 1300 
times in passing through it, which enablea us to 
look at him when setting without being daazled. 
The loKS of light, and consequently of heat, by th« 
absorbing power of the atmosphere, increosei with 
the obliquity of incidence. Of ten ^ousand raya 
fulling on its surface, 8123 arrive at a given point 
of the earth if tbey fall perpendiculariy ; 7024 arrive, 
if the angle of direction he fifty degrees ; 2831, If 
it be seven degrees ; and only five rays will arrive 
through a horizontal stratum. Since ao great % 
c^autity of light ia Unt Vn igunni^^tckxi^VVAt^ 



A 



S99 



MAGA2[NE OF SCIENCE. 



I 



nioipbere, many celestial objecti nujr be altogetbcr 
ioTiiible from tbe ptaiti, whirh tnnj bo trrn fmm 
elerattfd sttuationg. DimiDished splendour, and tbe 
falite e&timate we make of diatance from tbe number 
of ioterrening objecU, lead tu to sappoie the lun 
and moon to be much latter when in tbe horizon 
than at any other altitude, though their apparent 
dtiuneten are then somewhat leu. Instead of the 
sudden tranaitioiia of light and darkuesa, the re- 
flective power of the air adoma nature with the rosy 
and golden bnet of the Aurora ud twilight. Even 
when the bud is eiglite<*n drgreca below the horizon, 
a aulfident portion of light remains to show that, 
at the height of thirty milea it is still dense enough 
to reflect light. The atmosphere acatters the sun's 
raya, sad gives all the beautiful tints and cheerful- 
ness of day. It trmnnniui tbe blue light in greatest 
abo&dance ;' the higher we ascend, the sky asuuroes 
■ deeper hoe ; bat in the expanse of spare, the san 
aod Stan must appear like briiii^ot specks in pro- 
found blackness. 



AOUA TINTA ENGRAVrNG. 
Tui art of eagraTing on copper, after tbe manner 
of Indian ink. by which happy imitations are made 
of figures that have been drawn with the pencil in 
Indian luk, biitre, sepia, tec, particularly those 
which are on a large scnle. There arc seTcral sorts 
of it. In the Arst, aAcr the outlines of tbe figure 
have been etched, finely powdered mastic {cohphom 
nium) is sifted over the plate, which is then warmed 
OTer coals, that tbe mnstic may be melted. In this 
way, insensible spaces arc formed between the par- 
tidea of masdc, upon which tbe nitric acid is after- 
wards to act. The work ibeu goes on as in tbe 
mecxo-tinto. only Uiat tbe scraper is used in this, 
■od the pencil in thnt ; snd all the places where 
there is to be no work or shade, are covered with a 
thick black Tarnish, on which the acid does not set. 
7*he nitric acid is now poured on, and left to stand 
as long SB is neceKsarjf for tbe lightest shade — about 
five minutes. The light shades are now stop|>ed 
out with Tsmlsh, ond the acid allowed to set a 
second time, and this stopping out is continued till 
we come to tbe deepest shades, which are bit in last. 
This method is best for historical and architectural 
subjects i but in landscapes, in which the trees 
require more freedom of tlie pencil, the second is 
used. In this, a good etching ground is spread over 
tbe plate, and covered by means of hair<pcnnl, 
with oil of lavender or oil of turpentine, to which 
lomp-black is sometimes added. The oil softens 
the ground, which may be wiped off" with a fine 
linen cloth, leaving all the marks made with the 
pencil apparent on tbe copper. Then, aa in the 
first process, 6ne mastic is sifted over the plate, 
melted in and etched. This operation may be re- 
peated many times, according as there are more or 
fewer tinu in the original. By a happy union of 
both sorta, this style of engrariog is carried to a 
high degre* of perfection, and is partictitnrly sdapted 
to express the coloring of the air. where loi^ sur- 
fsces are oflen represented of one tint. In France 
and SwiUerland, the routette Is used— a little wheel 
or roller of steel, with a rough surface and several 
prominences, which, when it is rolled back and forth 
OB tbe plate, deepens tbe excavations made by the 
■aid. They have roulettes of all degrees of aixe sod 
le-^ventss, to make deeper or more shallow impres- 
sions on (he pUte, Frumtime to time, the psrticles 
trparstcd by thie prooew ere rwawrod with a scraper. 



I Tbe aqua tints mode wax first introduced ■ ahort 
' time since into Britain snd Germany ; end tJSr 
British, pariiouJarly since Gtlpin brought the art 
, into Dotioe, haveaJonied iheir Uterary worka ia tide 
I manner. 



STEAM AND THE STEAM ENGIXE. 
I Bxtitmedfmm pag« Sit j 
From the time of Hero until a oomparatiTelT tsie 
period no improvement appears to have be«D Bsede 
iu the application of steam ; yet if nothing ess 
be added to the history of this mighty agcot, e 
slight interest is ettachMl to the hct, that a hno«> 
ledge of its power was not extinct, some ef Ha 
effects being dreaded by the bjue bamera ot thrt 
period. " In the heart of some steoea/* accor^af 
to Albcrti, w1h> wrote in U12, " there arc fwtabi 
voids and concavities, in which air being shut ap, 
does sometimes produce incalciilsble mischief; for 
when they come to be touched by the fire, and the 
stone grows hot, it turns to x^povr, and, bursting 
the prison in which it ia confined, with a tremendow 
noise, blows up the whole kiln vrith a force atto- 
gether irresistible." 

The cause why ao many fiuta. known to the so* 
cients, and those of the power of steam amang 
number, should have been left unimproved 
many ages, is to be accounted for by the 
character of tbe phUosopben of the period, i 
profound knowledge was blended with tbe 
abflurditics ; when the maaa of mankind, unable 
appreciate useful ioTentionB while m tbe infim^ 
of them, were led away by thoac gross impositioos 
of priestcraft and self-styled philoeophy whieh over- 
run the balf-civilizni world for so many agea. mv 
state of things is well exemplified in the life of Clfr 
dan, who united the most tranacendant 
with tbe most cunsummste qaackery ; 
asgacity with the weakest superstition ; 
seen drawing on one page the Horoscope of 
and in another imploring his forgiveness for the sia 
of having eaten a partridge on a Friday, nnfoldJaj 
the moat beautiful relations in algebraic analjWi 
and foretelling from the appearance of specks ■ 
his nails his approach to some discovery ; abo<l 
all, eloquent in enforcing tbe obligations of a |«a 
religion, and cxpreasing the finest aeatieMnll it 
morals, while hts long life was one coAtioMd «» 
tion, grossly outraging both. Here this philose- 
pher, juggler, and madman, is entitled to brief mm* 
tion. from displaying in his writings a knowledge ll 
whst has been called the ' ' capabilities' ' of steam, mH 
more particularly with the fact of a eocitaim boif 
speedily pfocored by its eondtniMiion. Ue iIm 
early recommended that the heated fnligioow v^mjv 
" which escaped from every hearth should be turesi 
to a more profitable account •/' and in a later 
(1557) he gave a description and rude diagram 
machine, moved by heated air, wtuch, since his 
has received no improvement, although mv^ 
ployed, and well known aa the tmokf'Jaek, 

The next author who mentions the power 
is Mathcsius, a German, who, in a sermon pr 
in 1571, spoke of an apparatus giving an illi 
of the ** mighty effects which oould be predooeAl 
the volcanic force of a little imprisoned 
Following in the same track, about l£t77 
German writer substituted ateam fiar air, In 
ealled the whirling J^^pile, ae we have 
more than once figured a^ dflMribed. Tbi 
triTuocir howcTer. pomtm ti hot little ni 



ChM 



book. 



MAGAZINE OF SCIENCE. 



398 



ntility, being but very slight modtftcationt 
initrumcntA lotig previaqslj luggested by 
wiJ] be vfeu by the foUuwinf iUiutratioiu 
them. Still they are not to be n^lected, 
ty are steps in the history and applicatioD 
it H^Ut — Mtfom. 
celebrated Boptinta Porta (1606), an Italian 
»0|»her. inTVRtor of the camera obscora, was the 
rof scTcnil ingeniotu works, and, amung others, 
nmentary on the " Pncsumatica of Hero,'* in 
1^ deacribea and gives a dramng of a tteam 
^^ which wanted nothing but " the idfa of 
1ft application,'' and the proportional mag- 
S, to form a steam engiue for raising water. It 
M muderstood from the adjoining oat:— 




boQcr, in which steam is fbmung; it 

Che pipe K, into the cistern C, closed at 

and nearly filled with water; the pipe B 

the suffice of the water. The steam 

boiler is thai coDdacted into the space 

water, and pressing on the water by its 

wrr, fbrcej it through the tube D. F is a 

;by fresh wuter may be admitted to the 

The idea of Porta was neglected for half 

r, till Kircber, in 1656, re-invented thesamie 

or appropriated it to his own merit. The 

ia the form given to ICtrchcr's steam fouu- 

atthougb it is neater in Bppcunince thun 

the ideality of tlie priQciple of the two 

ident. A is the boiler, C the ateam-pipe, 

U ud O the jet of water. 




be, however, tliat Kircher tooV his invcn- 

De Cuiu or Branca, who published Uieir 

It the period intervening between the 



time of Porta and Kircber. The former of theis 
philosophers, De Caus, like most otlier philcMophera 
of this period, was struck with the njarvellous liy- 
drantic and pneumatic machines of Hero, and aimetL, 
as others had done before him, to imitate them. 
One of these contrivances he has given, u iUn«tra- 
tive of ^e fountain ; instead of the ball io Hcru'a 
problem, De Caus substitutes a boi for the water, 
with leiises inserted into its Ud, to increase the sun'e 
beat by concentrating his rays ; and in another dia- 
gram he pUeea the glasses io a frame, and throwi 
the auubeams on the outside. The pipe going from 
the etatem to the heated vessel he famished with ■ 
valve, opening upwards, to prevent the return of the 
water ; another valve ia placed in a pipe, leading 
from the heated vessel, also to perform the same 
office. Aa migbt have been expected the effect ii 
greatly enlarged in this improved apparatus. Hero 
was satisfied to make the water ha raited a small 
distance fall in drops : De Caus elevated bis to an 
iiDpoaiDg height, and it descended in copious jeta. 




Another marhine of a similar kind, described hf 
De Caus, in 1615, is perhaps the /Irtt instance in 
which steam was proposed to be used as a moving 
power on a large scale, in the manner in which it ia 
now npplicd, namely, by its elastic force when con- 
fined. Hi» theorem is, that water maybe raised by 
the aid of fire higher than ita own level ; In illus- 
tration of whiob, be gives the following fig;ure and 
description :— 




S94 



MAGAZIXE OF SCIENCE. 



Tiike a boU of copper, nurkeii A, well soldered at 
ttrery part. It miut have a vent bole, marked B, to 
put in the water, and also a lon^ tube, which ia aoU 
aered into the top of the ball, and the end ap- 
proacbea near to the bottom without toarhing it. 
After filling this ball with water, through the vent 
bole, stop it close, and put it on the tire ; then the 
bc«t atrikini; ac:ainKt the aaid ball will cause all the 
water to riae throQgh the tube. The steam formed 
^rj the erapuhzulion of the water having no exit, 
will accamulato until it haa anfticient elastic force to 
pita oa the surfcce of the water so strongly as to 
cmse part of the water to oacend through the tube, 
and by continuing the beat thus, all the water may 
be expelled, u De Caui says. ** This.*' saya Farey. 
" b all that De Cans baa left na on the aabject of 
, fleam, " De Cana diatinctly mentions this power as 
a means of raising water along with other pUos 
which were in actual operation for that purpoae, ao 
that be mast have considered it fit for purposes of 
utility, Bod thus very probably has given the hint, to 
oCbers. 

CTvle contimue/Lj 

STUTTERING; ITS CAUSE AND CURE. 

(/"ruffi AmotCt " Elmumtt nf Pkysici") 
STUTTERtNO, Stammering, or hesitation of speech, 
■re terms implying an interrupted articulation, ac> 
companied generally with more or lees of straining 
and diitortion of feature. It is rrmarkable with 
^Vcfpcct to this defect, that when the present work 
IB first published, scientific or regular medicine 
[bad taught as yet no certain cure for it, although 
tbc frequent success of non^professional. and often 
%norant individuals, by a mode of treatment which 
they solemnly bound their patients not to divulge, 
proved the cure in certain coses, to be both possi- 
,ple and not difficult. — The author's attcnlion had 
fibeen drawn to the subject some years before, by an 
interesting case submitted to him, of stuttering 
counected with other disease ; and it was in ana* 
lyzing the sabjert with a riew to the treatment of 
*:tbat casct that be framed the unslysts of articulation 
'contained in tlie prei^eding pnf^rs, and drew up 
a part of the additional observations which arc now 
to follow. A cure was obtained ; but as the casu 
,|»oaseaaed a favarable peculiarity in the powerful 
Ittiind of the indiridual. to which the author attri- 
buted great importance, and as ho had little leisure 
IVom his ordinary professional duties to punnie the 
■nbject, or to aaoertaio in what respects his plan 
night differ from that employed by the most sue* 
ceasfui of the practitioners who concealed their 
proceedings, be gave his remarks in former editions 
of this work, merely as continued elucidation of the 
subject of siieeiTh. He is now. however, enabled 
to state, that his analyais has completely detected 
the nature of the morbid affection, and that it direct* 
limplo and eficctusl means of relief. 

The most common case of Btuttering, however, 
is not, as h.u been most universally belicvpd, where 
the indiridual has • difficulty in respect to some 
particular ktter or articulation, by the disobwiicuce 
of Uie parts of the mouth which should form it to 
the will or power of association, but where the 
spasmodic interruption occurs altogether behind or 
beyond the mouth, rii. in the glottis, so as to 
affect all the articulations equally. To a person 
ignorant of anatomy, and therefore knowing not 
what or where the glotti* is, it may be sufficient 
explanation to mj, that it is the slit or narrow 



opening at the top of the windpipe, by wbieb tka 
air paaaes to sod from the lunga, being titaslsd 
just behind the root of the tongue. It is tbailubi^ 
is felt to clove suddenly in hiccup, arresting tka 
ingress of air, and that which rlosta, lo prctent 
tlie egress of air from the clteat of a person tifttag 
a heavy weight or making any straining rxertiM ( 
it is that also, by the repeated shutting of wbidi a 
person divides the sound in pronouncing levvd 
times, in distinct and rapid sacceasion, any voati^ 
as o, o, ft, o. Now, the glottis, during 
speech, needs never be cloned, and an ordioMyr 
atutterer ia inatantly cored, if by having his atMA- 
tion properly directed to it, he can keep it a|isB^ 
Had the edges or thin lips of theglotUa been vibiUb^ 
like the external lips of the mouth, the natnm W 
stnttering would not so long have remahiad a 
mysiery, and the effort necessary to the cure 
have been suggested to the most careleu o' 
but because they were hidden, and profi 
men had not detected in how Air they wi 
ccmod, and the patient himself had only 
feeling of aome difficulty, which after 
grimace, gesticulation, and som^ time« almosl 
convulsion of the body, gave way, the 
with respect to the subject baa reoiuncd 
many persons who by attention and much 
bad overcome the defect in themaelvea, aa 
mosthenes did, have not been able to descril 
others the nature of their efforts, so aa to ci 
imitation : and evidently the quacks who have 
ceeded in relieving many casn, but in manyj 
have failed, or have given only temporary 
have not really understood what precise end far 
action of the organs thrir imperfect directions s 
accomplishing. 

Noff, a ntutterer, underalanding of anatomy ooty 
what ia stated above, will comprehend wbxt be is ti 
aim it, by being farther toLd, that when any ooo* 
tinued sound ia issuing from his mouth, as when 
is bumming a single note or a tunc, the glo' 
necessarily open, and therefore, that when he 
to begin pronouncing or droning what «ra 
already described to be the simplest of vocal 
namely, the vowel e, and in its less distinct 
cation, as heard in the English word ceriam 
the French word ^ue (lo do which at aoce 
terer has difficulty), he thereby upena the 
and renders the pronunciation of any other 
easy : — or if, when speaking or reading, be 
his words togrthrr, nearly as a person joina 
in singing (and this may be done withoot Ha 
at all noted aa a peculiorily of speech, for 
persona do it in their ordinary conversatioa| 
voice never stops, the glottis never closes, ai 
is of course no stutter. The author hil 
merely this explanation or lesson, with ex 
to persons who before would have required 
hour to read a pag^i but who immediately 
wards read it quite smoothly ; and who th< 
transferring the lesson to the speech, by c 
practice and attention, obtained the aame 

with respect to it. There are many peraona 

counted peculiar in their speech, who in sertiBC 
words to expresa themselves, or while coming to e 
decision, often rest between their words ou da 
simple sound of e mentioned above, saying, forts* 

stance, hesitatingly, "e [ e thfak 

e I shall,'' — the sonnd never ceasing and 

the end of the sentence, however lonir it rniy 
delayed. Now, a stutterer, who, to 
at the begtmung of a phrasei or in > 



ikm^ 



MAGAZINE OF SCIENCE. 



S95 



topUon. UKt inch a loond, would not 
tst be more remirk0ble than a drBwUog 
nd be vould only' require to drawl for k 
5t until practice fuciliutcd bi« cummaad 
^er ftouDils. Although producing the 
md mentiouHl ii a meiiDS of opening the 
■eh by ftutterers ii fuuntt very generally 
f there are cases in which other each 

^be more Bailable, as the tntelligent pre- 
lOon discover. Were it possible to 
k Derres of the muscles which close the 
ithont at the same lime deslruying the 
,|U'odaring voice, such an operation would 
lediate and certain core of stuttering, 
the spasmodic cloaure of the glottis, as 
pribed, is ibe common cause of statteringt 
laIso cases in wliicb the cause is a spa«> 
llongBtion of soma of the aspirates or 
il sounds, as of «, m, /, &c. Fortunately, 
,the aubatitiitioQ of the simple sound is 
le cure for all. 

itbe cure of many stnttererH has been ac- 
id by their ow^ efforts, after the study of 
ritteJo in this section, for others, and par* 
youog people, the following have been 
farther useful roles or forma of direc- 
commcnlary upon them making them 
Dtelli^ililr, wuuld Eeem to comprehend all 
he oommuaicatcd upon the subject. — 1. 
9 youraelf with the idea of a continued 
of the roar of the sea or waterfall, or the 
\ organ-pipe, and fud that your speech is 
DDtoterrupted.— 2. Then never stutter 
Bsbstituta always the simple continued 
way threatened defect, and rest upon it 
|r be felt to overcome the difficulty. — 3. 
It words or syllablea. — 4. The simple 
become the first syllable {elotely joined) 
UfficuU word, until the morbid habit be 
, The object of all these directions is to 
I palient, first, to substitute universally 
far the stutter, and then, sj soon as poa- 
botrd the drawl too. 

9 g;iven above of the nature of stuttering 
Ve, eipUins the following facts, which to 

■KM bare hitlierto appeared extraordinary. 

ftoften cau sing well, and without any inter- 
br the tnne being continued, Uie glottis 
close* — Many stutterers can also read 
U, or any declamatory composition, in 
\ BD'mterrupted tone is almost as remark- 
lingiog. — A person who draws in a deep 
Bra beginning to speak, a& he cannot long 
pflir, and the glottis must be open to let it 

10 a degree secured against the occurrence 
big. The secret remedy of an American 
ID. years ago, got much money from En- 
^waa tlie direction thus to fill the cheat 
ginning to spcAk. A Dr. Mc(^ormMc, 
jinbUsbed a work on this subject, founded 
poneoos idea lliut stuttering was an ellurt 
while inhaling air, instead of while ex> 
kve the same direction. — The cause of 

being a weak and enttily disturbed aaso- 
certain muscular actions, we have the 
by any degree of aniiety or dread as to 
well eiceedingly increases the defect ; 
^naoy stutterers, who cannot make Chem- 
llllgible in society, Htill, when alone, can 
\ read as perfectly as any other person. 
Bns also why many stutterers, who have 
fat » time at tht houses of pretiaided 



curersof their defect, have felt tbemtielves singularty 
reheved from the moment of entering the boosfl ; 
because, kaowiog that they were expected to speak 
illf Oiey had no fear of disagreeably attracting at* 
tention. und thert-fore hud their powers much mora 
at command. These persons, on returoing to the 
world, have generally itutCered aa badly as ever, but 
many of the asserted cures of stuttering, with cer- 
tificates obtained from the parties at the time, have 
been of the nature now described. — The cuuse of 
stuttering being so simple as above deacribed, one 
rule giveo and explained, may, in certain cases, in- 
alantly cure the defect, however aggravated, as has 
beea observed in not a few instances ; and this ex- 
plaioB also why an ignorant pretender may occa- 
sionally auoceed in coring, by giving a rule of which 
be knows not the reason, and which he cannot 
modify to the peculiarities of other cases. — The 
same view of the subject eaplaina why the speaeh 
of a stutterer has been correctly compared to the 
escapf of liquid from a bottle with a lung narrow 
neck, coming — " either by hurried gushes or not 
at ail:" for when tbe glottis is once opened, and 
the stutterer feels that he has the power of ut- 
terance, he is glad to hurry out as many words aa 
he can, before tbe interruption recurs. 



STRAW PLAT. 
Thb culm or stalk of different species of gross is 
now BO commonly applied in this country as a lua- 
tcrial for making hats and bonnets, that its intro- 
duction might naturally be supposed to be of ancient 
date. It is, however, scarcely half a century since 
the simple art of platting straws together was firgt 
practised to any considerable extent by our rustic 
population. Immediately previous to the intro- 
duction of straw hais, those made of chip were 
usually worn by our fair cuuutrywomen ; and the 
first nido attempts of our own manufactonea were 
then rejected by the higher classes for the more 
finished productions of Italy. The coarse British 
plat was, however, adopted by the more humble in 
the middle ranks of society, and the home manufac- 
facture gradually increased in importance. This 
originated in Scotland, but a work in which oven 
children could be profitably employed, and which 
they could soon learn to perform with considerable 
skill and dexterity, was quickly introduced into some 
of our Eujflish counties, and the wives and children 
of thepeafuintry of Buckinghamshire, Hertfordshirer 
and especially Uedfordsbire, gradually became en- 
gaged io an occupntion which required so little 
instruction. Dunstoble plat soon became noticed 
as tbe beat produced in England ; it still retains ita 
place, and continues to give ita name to English 
straw hats of superior quality. 

The firHt marked improvement in British plat 
consisted in interlacing straw previously split Into 
fine and similar stri)» ; the culm used for this pur- 
pose in tbe iufaiicy of the manufacture having been 
thick and of unequal sizeu, producing a very coarse 
and uneven plat. From that period this branch of 
domestic industry has increased rapidly in England. 
Many other great improvements have been made ia 
the material and manufacture of this article since ita 
first introduction ; and many are the varieties of 
fancy straw plat which have, each in their torn fur a 
brief period been adopted by thoae fickle patroneasea 
the vouries of fashion. All plata must, however, 
give place to that of Italy, which is still considered 
superior to any otber. Numeroua attcmpta have 



sdff 



MAGAZINE OF SCIENCE. 



been Bade, it Tsrions tifflcs, tn eqnal the Italian 
put ; but althougb this manufacture !a apparently 
•0 taMj of inaitation, yet perltapt neither the French 
nor English hove ever produced any thing fully 
efjoal to the Italian huts of the beit quality. These 
are well known In trade u Leghorn itraw, ao called 
from the port whence they are eiporled ; hut they 
are in reality manufactured throughout Tuacany, 
and mone especially in the rale of Amo, where the 
female peasantry find full and profitable employmeDt 
in this occupation. At every cottage door women 
and children are to be seen busily engaged picking 
and platting straws ; and even when taking their 
walka they generally continae Che easy work of 
plstcitig. 

Bnidea the grvat consumption in Europe of this 
well-known article, large quantities are acot to the 
North American states. An intelligent traveller has 
Obser\-ed, on witnessing the Tuscan peasantry thus 
occupied, that " the work produces at erery step the 
pleasing app>earancfl of labour united to amusement, 
—of a toil in which childish play and childish gains 
form children to habits of industry without ex- 
hausting their strength or gaiety.** The women 
and children in nearly every part of Tuscany wear 
large straw bats, entirely prepared and made by 
themselves. These give them a very neat appear- 
ance ; but altogether the peasantry of this state 
•eera to be in a better condition than those of any 
other part of Italy. They owe this niperiority 
rather tn their own iDdustrious, frugal habits, than 
to any material diflTerence of government or taxa- 
tton. The material of which the plat is made is 
■onetimes prepared from the straw of rice and of 
tjaor darnel grass. Hut the straw principally used 
ia the culm of a kind of red wheat, very commonly 
cultivated in the Tuscan states. It is a variety of 
Ipflt corn, or red wheat {trittcttm tpHta), liaving 
somewhat the appearance of barley ; the grains 
grow in the ears In a similar manner, but their shape 
ii Like that of other wheat. 

Although apparently a very simple process, some 
■kill and patience are required tn prepare, split, 
and plat the straw, snd to perform all the other 
operations without breokiog so fragile a materiul. 
The wheat is allowed to grow till just ready to bunt 
into ear. The straw is then pulled up by the roots, 
which, u well as the ear, is cut ofl* from every 
■tem ; ■■ sooo as cut, it is tied in small bundles, 
immrricd for a short time in boiling water, and 
sprrad out to dry. This being done, the kuou are 
cut off, and the most slender straws are put aside to 
be platted whole, from which the beat and most 
duivblc bats arc made. The others are split longi- 
tudinally, with the point of a penknife, into two or 
three parhi. These are again moistened and pressed 
flat for three or four hours, and they are then rcsdy 
for platting. When hata of an r-xtraordinary fine- 
ness are to be made, the straws are divided into a 
greater nnmber of strips ; the poiut of a knife 
cannot, however, be depended upon In ho minute a 
division. A row of very fine small needles are 
Mnnaotcd together at their heads with rosin, the 
iVtta each other beiug regulnted by the 
of teeneie to which the straw is required to 
A flattened strip is then passed through 
lies, which readily divide it to almost any 
Anullier contrivance 
the straw. This is 
cone, the lesser end 



^ipm of asaignable exility, ii 
U iMi i» England for dividing 
Ai A^WfeMi I? a small hollow ( 



of which has a mimber of shorp (eetli 
opening. These cot the stnw as it ts 
through the cone ioto strips more or less 
according to the number and proximity of tba t 

Some practice and a delicate hand ore reqtur 
form ao even plat with a number of these m 
strips, and to keep them disentangled and in 
places without breaking them. Each pist ts 
with seven, nine, eleven, or thirteen slips of ■! 
it may therefore be supposed that some degi 
nicety is required ia its extrcution. This em 
ment is most usually assigned to femalea. as 
more particularly appropriate to their habits. 
Italian plat ia considered fine when fourteen or 
knitted together do not exceed four inches in bn 
Leghorn plat has always been much esteem 
England, as being very superior to our home n 
facture, and it has long formed an article of 
siderable importation, either as made up to the 
of hats, or in the simple pUt. Daring th4 
war the importation of this article waa atti 
with so much expense and difficulty, as neai 
annihilate this branch of foreign commerce, 
home manufacture was, in consequence, very 
increased nnd encouraged ; its improvement 
wise became an object of Aaportanoe. and 
attempts were made to render all foreign aai 
unnecessary. 

Mr. Corstoo, an eminent msnofacturer of 
hats, was among the first who took active mes 
to promote this desired result, and at the begil 
of the present century, he node strenuous exei 
to obtain a successful imitation of the Leghon 
in this country. In prosecuting his endeavowi 
persevering energy, he appears to have been acO 
more by the disinterested feelings of the pi 
throphst than by thtr petty views of the tradMJ 
and to obtain an increase of healthy and pitti 
occupation for his countrywomen in the htu 
walks of life was the ruling motive for bis exci 
Taking an average of the ten years precedtag II 
he foand that 78.000 Leghorn bats were Imp 
annually into England, besides i quantity of 
which, supposing five hats are made fron 
pound of plat, could be mannfactured into tn 
three thousand more. From this, and other 
he calculated that if the foreign plat were supen 
by that of English growth and manufacture, 
ptoyment would at once be obtained for 5,000 y 
women and female children ; and that 2,000 
of very poor land, unfit for other pnrpoaoa,! 
be brought ioto profitable cultivation. Pb 
fiirtherotice of his object he instituted a wekt 
Fincbam. in Norfolk. On a poor and sand; 
rye-gnisa seed was sown, in the proportion oil 
bushels per acre. Each of these acres pnk 
forty pieces of Leghorn plat of fifty-five yar 
length, and employed for one week thirteen cb) 
to sort the straw, and eighty plat it. 

Three rears were spent by Mr. Corston in ft 
ing this manufacture to perfection, before his e 
were crowned with success. It appears tk 
was then rewarded with their gold medal b; 
Society for the Encouragement of Arta, Accl 
exertions did not, however, meet with that m 
wliich had been anticipated. For when p« 
length restored to Europe free commercial ) 
course, the demand for, and the supply <^ ft* 
hata became greater than ever. 

fToUctmtHtwtlJ 



by II. Pauwia. S. WIUt« Horee Lane. lUl* Bad.— PvblUwd tiy W. Bojrram. II. 
<ttkkli are atuwrrcd Monthly, J Ig ba addrratfd to tbe Editor, at ST. ColUgt Ctvr; Ulla Emi Ml 




V 



THE 



AGAZINE OF SCIENCE 

anft Srbool of a«g. 




■J!IS 



MAGA2:iNE OF SCIENCE, 



KLKlTIKI-MAONETIC CLOCK. 

f To M.* Kiiitor J 
Stn. — V.wT yt\f\\\nti to promote the QtilitT of your 
r\ivUcnt MAcnzinr, I hieg lrav« to forward to joa 
■ ilcMmption and figurrs rtflative to an Electro- 
MaiciiHic Clock ; to iniwrt wliitrh, in jronr valuable 
pa|cr», if deemed worth?, wilt greatlj obliee voar 
humble verTant, ' J. parnkll. 

I'lftT tXiyi^n, .V.'i. l'«J». 1S«I. 

Vxf. I. repre«entic the clix-k. D is the diaUplate. 
writh a raje C behind. whieh oontaint the wheel-work, 
fixed on a box B. in which the |<en -ulum of th^ clock 
c«cilla(e« : we witl suppose that one t\de of ihia box 
is rrmOTed. to u to ei)v-*«e to view its Ktioo : P 
rrpmeul* a penJalun oi >ach a 'ien£ih at to beiC 
•r<\-m<^ ; neu the extrroctr of P ant fixed two 
picvv* of tSrel or irva. one on each fide of it. or 
the K?^ wtT re of iron. Oa the lower «*« are rwo 
eJectTv tr.A^.ea M N. b«:we<r. wh .-1: :be pe&ieluai 
««cC&t<f : the i>e£-==.=c arc :e.-=::5iUoa of eica 
oc tbf A"l» a.-e cvLzecced wt:i aa arr*-*:** ra tae 



■i KTfw*. fee Si* 






C! 



ea.-* eL^r-v**-: 



:-TO«e ;: =kfc 



c'-s 



iS* 



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r::. a 



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w:tf-2 



T. w;ir; K-.-T-i?. ;.- r i. 
^■^T'.-c ■•istf-j a: '.!< ::;* •>' ' 

jM.^ft.T^i p-cidie T^iTjc fc.-^« N at: P s .**-■ 
•wt-^jM :' TMttB» .V a K--":^ S «ii i;-* :■"«** r-t 
C iT. V w;a.-± aw ii:*i :« .--t.--:* its r»-* ~Ai;^_ 
•: ?cra »^ rf U'! M.- C %." i.-^ *a: t-- r *"i* '-■ '^■ 

Ka-wf's* w-::i Utf ?;"TJ .*jr'>:* i- im .-.'-» a? »*:: 
n ritf f-ipir* *,■ "-'i" «:«-'i v ^. j * ue T^.-w^ri.*: 
'T^TTTsi.'wftM. a :J'; r^;--^- -■! s-r-.'T-rT^ •-.. ?:"!' 

»- f Tttw fc'w-: > t^i ^* •-" ? ""-■ ^'- ■•■-'-? ■'• 

,-1 kv u..-^r^ Tr? .— .> n 
■n.-?u i.'Mi :v :.-ui" -"■•«: * - 
7^i>.t ?iiw< "^. ~~^--~" '*■' "'"■ 

w- ^ * : r ■-;-. -v^i-;. i a. -" -^ --r-- w^- *»-J4 

^i ** t n inKU-iic " * 
fciw ar»^?» ivrMld *> -■*-■«- 

«TW K.<CUf -z^ds* ?«.«» a« 

- v.:traf* -■»? .-liinc » •■'w* 

■J i".:r ZK r*"Tairr TiJ* 

*f. .-iJv* r« Bv'Uat' *v a 

X. a : h.-l l.tt !•.' >stt. 

I .--w -.fir *:*>t:wu iwv* -' * 

«-iil :m.- «"■■■:••• '-f* ■'^' •• 
^ ,. '^ ^w-^w- . , ^ 






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1.x 1^ 



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1 *if 



fcl*'^-!* 



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» *." 



t ■,- *»«* t:n>e 






volume. In the fir^t sentence below, o 
pendent is certainly in error, in implyini 
thing should be kept back, bfoausc! it inaj 
curred tu those who are alreiidy atHjuuintfi 
suhject ; our objixt is inntruction to tlin&e i 
infonustion, and in working out t\ni v 
Diuat not sannifie that they know the ni.-«ttr 
else where shall a line of dtfinarc-ition L 
and what precise amount of knowledge on 
demand that our readers shall have prev 
quired. In the succeeding part of the If ttei 
doubt quite correct in the explanation o 
called ** magnetic*' spark, hwi it is evident 
former correspondent intended to otTf r a si 
luefttl iostrument, rather than to explain 
colittet of tcimcef and after all, the onl; 
seems is osing the word produced instead of 
acti this may po»sibty hare been a prinTcr's 
if endent, howrTer, that both corrcspondetii 
desire but our benefit, therefore we th; 
both, and have added these reinark5, onl} 
we are anxious and always hare been, to i 
feai any apiTOach to angry di>cus>i(rn, pji 
r^lirlve to the c>'H>d-njtnred commutiic:itio: 
Tr^r^jr.kiec:} : at the same time, we are 
crrecs acy aai every error. We trust we 
a_.:vfi &lso to 2>i>i. thtl we hope no srienti 
V ^ w:::.::o.i L.s crntribution undt-r the in 
:i.*: c:bf r» a.~e as clevrr as hiinsrlf. It' In 
Tt±i :-; letters we rrccived in a single wci 
an ixr.'e&u» would be effectually remove' 

?:t — Tie experi-aent which your corres 
\l",Vr. efL::?!!* :a the Isst part of your Ma 
*i:; L ;t li'.r.e hai struck the mind of ever 
w-.- LiS :':• o=e morcrnt considered thepri 
ft =ix-«':r-e>j'trcjl michine ; the mere la 
srari ."a^ :< ejhted by iaU simple menn^, 
^-:vs^i =:=y x^nths ago. Again, he says 
-■ r AC*-*- :" spirk is produced; now if hi 
r: fsiy *.-it lit tjuk which is produced is 
zx.ijt^z :y ^e pa»n^ of the mngneiic tluit 
ifxrs '^ sii:e. ;hit I totally disagree with 
lu^ roi^t. I bii'lJ. and so I think most oti 
K'cs i:. *kbi:. forasmurh as electricity cir 
t.:cc 1:1 iss^ited conductor around a bdi 
T-.a :zixt* maf&etism into that bar, there 
r^arene of tlis is true, that when magm 
ncartii a* ia the case in question.) into 1 
24.-. tJeczr^^^ is circulating along the ii 
nKcnrcoe : and. moreorer. the fluid here circ 
»*»:eTeT !t may be. produces exactly th 
rffc;s » vcCuic electricity. Nevertheless, 
i« t: fr.'x se to pull down that which any 
:s-tt«cf;: —av bate kindly contributed to yo 
ctx^i ; r.: illow me to add, that I write thi; 
litrsi:::* d:*.-e*p^ct to no man ; but merely 
Si,^. t' }•:'***•''. your meritorious exertions 
a^«aaA£ie:it of the ** Magaiine of Science.' 

J. PABN 
ils;.f.m. X.T. tS.'\, 1*41. 



MONSOON'S AND TRADE WIND 
1^0*1 winds which blow in a certain direct 
a tine, and at certain stated seasons chang 
bldw for an equ.d space of time from the o 
ptnnl of the coi)ipA.<s. are called monsoons. 
the months of April, May, June, July, Augi 
September, the wind blotrs from southwar 
the whole len:;th of the Indian ocean, sir., b 
ihe ptnlkla of 28"* N. uid 26'' S. Ucitud 



MAGAZINE OF SCIENCE. 



299 



en the eastern coast of Africt and the meridisn 

fMi9u>4 through the wfiitem part of Japio ; 
t Ihe other month!), Octohrr, November, De. 
*r. Jniiuarr, Februnry, and Mardi. ibe winds 
the nonhent parts of the Indian ocean shift 
1, and Mow di'rectlj contrary to the courie they 
Id the former «ix months. For nome day» 
I and after the rJijin|;e, there are calms, virl- 
■pdf, and tremriidoun fltorms with thunder. 
I^iiovophen ditfcr in their opinion* re»pect- 
M ratiie of the^e periodical winds ; but a 
probnble theory of the general trade winds ia, 
hey are oreasitined by the heat of the sun in 
gtooi about the equator, where the air is heated 
leater dr^rre, and consequently rarefied more 
in the more northern parts of the globe. 

this expansion of the nir in these tropical 
ta, the dcoser air. tn higher latitudes, tushcf 
Uy towards the eqoator from botli sidea of 
obe. By this contlux of the denser air. witb- 
ly other eircnmsrancen intenreninj, a direct 
iriy wind would be produord in the northern 
I and a aoitthern one in the other tropic; but 
earth's diurnal motion varies the direct in* 
t of the sun over the surface of the earth, 

by that motion this inlluence is commnni- 
from east to vest, an easterly wind would be 
Bed if this influence alone prevailed. On 
tt of the co-operation of these two cause* at 
ne time, the trade-winds blow naturally from 
E. on the north, snd from the S.E. on the 
of the line, tbrooghout the whole yenr; but 
■un approuches nearer the tropic of C'lncer 
' satnrDer vcasun, the point towards which 
innd« ire dirprted will not be invarinbly the 
but they will incline more townrds the north 
: seaxtin, snd more towards the south in our 
. The land nnd sea breezes in the tropical 
bnay be considered as partial interroptioris 
Plli^ral trade-windii ; and the cause of these 
n very dlfBciilc to explain. From water beini^ 
r coailiictur of hent than earth, the wnter is 

of a more even trmperatnrr. During the 
erefore, the land bpromesconBidcrubly heated, 

nreticd. and consequently in the al'tenioon 
ie lets in from the sea, which is less heated 
t time than the land. On the other hand, 

the night, the earth loses its surplus heat, 
lie aea continnea more even in its tempera- 
awards morning, therefore, a breeie regularly 
da from the land towards tlie ocean, where 
> is wanner, and conseqacDtly more rarefied, 
B shore. 

cause of the monsoons ia not so well under- 
m that of the general trade. winds ; bat what 
leu just remarked augccsts, at lejiat, a pro> 
beory on the subject. It is well-known, that 

(<]Qator the changes of heat and cold are 
med hy the dinrnal motion of the earth, and 
c difference between the heat of the day and 
(bt is almost all that is perceived In those 
1 regions ; whereas in the polar regions the 
ridsaitudes of heat and MJd are occasioned 
annual motion of the globe, which produces 
»»tble changes of winter and summer; con- 
tly, if the heat of the sun was the only cause 
variation of the windu, the ch;ini;es, if any, 
Uld be produced by those means in tquatohal 
■pogfat to be diuronl only, but the change-s 
B pole should be experienced only onre in 
nths. As the effects arising from the beat of 
I opoo the air moat be grvalcr at tho equator 



L 



than at the poles, the changes of tbt wind ariung 
from the expansion uf the air by the sun's rays 
must be more steady in equatonal Uian in polar 
regions. The incontrovertible evidence of naviga- 
tors proves this Inith, that winds are more variablt 
towards the poles, and more constant towards the 
equator. But in summer, the continual heat, evea 
in hl^h latitudes, comes to be sensibly felt, and pro- 
duces chnngcs on the wind, which are distinctly 
perceptible. In our own cold rcgiun, the etfccts of 
the sun on the wind are felt during the summer 
inontfaa ; for while the weather in that season of the 
year is fine, the wind generally becomes stronger as 
the time of the day advances, and dies away to- 
ward« the eTening, and assumea that pleasing serenitj 
so dtrli^htf^l to our feeling*. Such arc the diamat 
changes of the wind in northern climates. Tha 
annual rfvoiution of the sun produces sliU mora 
sensible effects. The prevalence of the western 
winds during summer we may attribute to this causc» 
which is still more percrplible in France and Spain, 
because the continent of land to the eastward being 
heatnt more than the waters of the Atlantic ocean, 
the air is drawn, during that season, towards the 
east, and oonaeqneutly produces a wetttern wind. 
But these effects are much more perceptible in 
countries near (he tropics than with us. For when 
the tun approoches the tropic of Cancer, the soil of 
Persia, Bengal, China, end tlie adjaiuing countries, 
becomes »o murJi more heated than the aea to tho 
southward of those countries, that the cnrrent of 
the general trsde-wind ia interrupted, so as to blow 
at that season from the south to the north, contrary 
tn what it would do if no limd was there. But as 
the hii;h mountains of Africa, during all the year, 
are extremely cold, the low counthca of India, to 
the eastward of it, became hotter than Africa in 
summer, and the air is naturally drawn thence to 
the eastward. Prom the same cause it follows that 
the trade.wiud in the Indian ocran, from April till 
October, blows in a north-east dikrctioa, contrary 
to that fif the general trade-wind in open seaa, in 
the same Utifudr; hut when the sun retires towards 
the tropic of Cupricom, these northern parts be- 
come cooler, snd the general trade-wind assumes its 
natural direction. 

Having given the most obvioas causes of the 
periodical monsoons in the Indian seas, it is neces- 
sary to observe that no monsoon takes place to the 
southward of the equator, except in that part of the 
ocean adjoining to New HolUnd. There the same 
causes concur to produce a monsoon as in the 
northern tropic, and similar appearances take place. 
From October till Aprd, tite monsoon sets in from 
the N.W, to S.E. opposite to the general course of 
the trade-wind on the other aide of the line ; and 
here also the general trsde-wind resumes its usual 
course during the other months, which cunslitute 
the winter season in these regions. It may not be 
improper to conclude this account of the tropical 
winds, by enumerating some of the principal intleo- 
tions of the mnnstjona. Brtween the months of 
April and October the winds blow coastanlly from 
W.S.W. in all that part of the Indian ocean which 
lirs between Mudagnsrar and Cape Comorin. and 
ill the contrary direction from October till April, 
with some smiill varintiiin in different places ; but 
in the Bay of Bengal these winds are neither so 
strong nor no constant aa in the Indiou ocean. It 
must also he remarked, that the S.W. winds in those 
seas are more southerly on the Affican aide, and 
more westerly on the side of India i but these xmH' 



MAGAZINE OF SCIENCE:. 



irtioDS are not to iirtnt u to b« rrpngnaiit to the 
ral theur^. Tbtt ranw of ibit viristum is, u 
before intimati^d, that the mounuinoat lands 
Africa are colder than the fliilrr refion« of 
Arabia and India ; conttrqurntly tbe wind tuCunilljr 
blows from thc::W cold mouDtain», la tbe ttunmer 
season, towardi the wanner lands of Acta, wbich 
occasions those tnflerlionB o( tbe wind to the e«st- 
ward dohng tbe summer months. The peniDSola 
of India lying so moch faribvr to the soatb tiun 
the kingdoms of Arabia and Persia, adds greatly to 
this cfTect, because ibe wind nsturallj draws towards 
them, and produces that easterly TsriAtioa of the 
monsoon which takes place in this part of the ocean , 
while the sandy deserts of Arabts drsw tbe winds 
more directly nurthward, near the African coast. 
A timilar chain of rea»onihj^ will serve to explain 
any other inflections or variations that may occar 
ill the perusal of books of travels, 9tc. 



MANUFACTURE OP CHAINS. 

{ Sriumeil ffymt jmgf ZVt, ami t^imJti d ft t .t 

Iv the luhstitutioa of iron for hemp in the mnnu- 
ikctare of cables, the two ^rcat deaiderata, dura- 
bility snd security, are largely srciired in the Ofc of 
tbe former materiiil : the next object has been to 
unite with these, economy in the expense and light- 
ness in the article. Tlie amazing stress which a 
large ship riding at anchor in foal weather exerts 
upon the cable, can hardly be coooeived by tboae 
who bare oerer witnessed its effects. Next, there- 
lore, to tlie necessity for the iron and Uie work- 
aiansbip being such as should not give way, it was 
UidtBf>enBiible that the links shoulJ not draw together 
•t the 8ide« from great lon^ludinal iUtnt To secnre 
this end. it has become commoi., in making the 
heariest cablen, to place within each link a stout bar 
to prevent lateral compression, in the maimer re- 
presented by the annexed sketch of a poitmn of the 
chain of the Meiart. AcramaD, of Briacot. 



It has been contended hy some persons, that any 
■dTintagea supposed to be derived from stays or 
bars inserted In the direction of the shorter axis of 
the fKnk are more than conntcrbalanced by coii' 
comilant inconveniences. In the 6rst place, tlie 
ponderous chains u^ed as cabki ore rendered so 
much heavier by this addition of metui, as to amount 
to a serious drawbtirk on their acknowledged excel- 
lence in other respects : secondly, when the bars 
nre made, as has been tbe case, with painted ends, 
inserted by mttAns of boles or mnrtirea into the 
aides of the link, they are ssid to be llsble during 
an extraordinary Htrniu to be driven through or tnio 
the aides, and thuR to Kpttc the iron : and. thirHly, 
that these, bars distending the cidfs of nn cllipnL-4l 
link, BO OS to prevent it from collapaiog at all under 
any circumstances, tbe chain ii on thia ai-count. 
rendered rather less than more rfTertive os to its 
ultimate degree of security. In 1H2U, a canar of 
infringement of patent, arising out of improvements 
on the above contrivance, was tried at the King's 
Bench, viz. Rrtmton rrnw Hawka and Co. The 
case alleged that the defendants were manuracturing 
cable chains mi the prinriple nf those for which the 
plaintitf had, in IKl.H, obtained a patent ; an tnjunr- 
tion of reatnaint was therefore prayed for. The 



•olIdtor-generaL for the defendastsi conttsiU tksl 

bis dienU had not copied their link fro» lUl 

descrit>ed in the plaintiff^s drawing, but hwl aattlf 

used an ovdl link with a stay in it. tni wirrt bid 

not only been before patented t*' ^a. 

but was, aa he shnald protr, a v^ -r. 

and therefore the plamtifT coald u ' 

exclusive right in it. A number of w i : 

examined to prore tluit link? nith ^' r- 

been made before eilbrr tbe plm^ ' ' ,' 

Brown took out pnlrnts for lhcu> ; u - 

nailon deputed that, so long ss tbirtj n- 

ago they bad worked up uM links with t 

to those Heforv tbem in court. Tlicre Uiii Mik^ 

pear, however, any good evidence to prova tbstaif 

stay bad been manufactured before I^' 

the aamc principle, namelj, instead of b* 

at tbe ends and thick in the miiJdle, w*» •|>t>M> «> 

at the ends ao aa to overlap the aides of ikm tll4l 

an arrangement, in the opinion of Mr nnin»&, 

entirely new, and far suf*rior to any * 

been prerioosly introduced. Dr. Oliniin- 

of tbe lloyoi Military Academy, Woolwicl, »«»* 

maleriul witness on this tnat. and tbe substsM* 

his testimony is interesting oit tlie pih 

He stated, that one pc'-uliar merit of !■ 

chain mhic was, that theie was a stay }■ 

each Imk, to keep the sides of ibc lit' 

lapsing ; that this stay wm« msde bruatl a: 

to support a eonstderable portion of ih* •>«« 

the link ; and that the stay was made to Up 

half around tbat porlitm of Ibe link, •^i* 

kept from falling out by its own fiuni. 

sides of the link being at all weakened 07 unj 

dentation into its subsCance. as was the 

stiyi formerly put into the liuha of chains: 

peculiar merit of tbe plainiifTs improw 

cbaiit cables was, that he made Ihoar pnrtf cf 

link that were between tbe stay and the 

ing link in a straight line as near as 

the whole link and stay being in 

that is. without having any twist n 

links had. by whtrh arrangefieui. c. ■ , 

link was subjected to an equal litrain. 

strongest possible form into which iron 

for tbe por]Msesof achain cable. Tbe " 

that he bad made experimenia on two sof 

one with the link as described in the pUii^fi 

sprcificBtion, and the other chain with the 

elliptic links without a stay : tbat be 

chain of two by uniting their ends, ai 

them to a great strain, which changrd ^'^ 

each elliptic link, so as to weaken 

tially ; and at length broke that r-hai-i 

the least degree injuring tbe platntifTs hnl 

witness afterwards tried, in the same 

piece of chain with elliptical links, ha^ 

each link, which bore a much greater 

tbe other, but finally broke, without the {)«i?it 

suffering any injury whatever. 

Captain Brown's link is twisted, ao as to 
of a certain decree of exteusKin in case Ct 
violrnt streu ; but in the opinion of Mr. 
civil engineer, the weight of a cable ebaio ■ 
than equivalent to any elasticity wbicb ean be 
to a link by twisting, in rrsi«iing the auddeai 
which are grnerally occasioned by a rough 
elasticity cnnuut be given mthuut we?''-—" 
iron, B9 every chunge of figure nf tJ 
dnced by a straiit, tendti to injure tti' 
iron (tnd ruprure it. It was witli the i 
Captain Brown and Mr- Bc«iitoo> ■nd :•• 




m 






MAGAZINE OF SCIENCE. 



301 



•sd rtftttlt of the trial jast mnitionfd beFore thetn 

Ibtt fn October 1820, William and Dnniel \cmman 

two flriftol iron>mutrra, obtained their pntriil fur 

•* certain improvements in t\\r procea»r« nf forming 

the msteriats f'ur anrl mQiiiifncturin^ cliain* and L-liuin 

(•ifilf. " BpaiJes the tendency of the pointed »i*y* 

Mito the side of the link, u itated by Or. 

on the trial alladed to, another witnesi on 

tkc aiUer hand took occflsian to state that he hjtd 

meem portions of that part of Brunton's otaj which 

iverUpi the link bruken oflf. Tu obvinta 

'L> ineoriTenieni-es. and at the same time to 

ir of the property of otheri. the Bristol 

» de*iwd a link on an entirely new con- 

Tbcy fo^cd cylindrirat bars of iron, 

19 or swell*. BO placed on the sides 

. >i.-ea, thut when the bar wbi formed or 

turiieti into a link, those projections would fall 

exactly opposite each other, and ihuj by their con- 




st form a moil eSeebul stay, perfectly immore* 

i\e by pressure or strain. In links of this de- 

rription it is obvious there are nu ihiu ed^ea or 

Bfglea liable to be chipped off or worn away. In 

•other cases, as in the section of chain first repre* 

"•mtcdt Uie projeetiona or swells being left somewhat 

■re both indented or countersurik so oa to 

reccaaea for the reception of a stay, wkicU is 

sd. and closed in by prwifturr, onThe bar 

tmrned into a link ; the cylindrical part of the 

bein^ prcserrrd, and retaining more streni^th 

«abatanct! in this than in any other part of the 

Tlie extremities of each bar are scarfed, so 

fold over each other asiifiieient Icngih, aod by 

neanit t:ive to that part of tbe link whiirh is 

or wcltlrd, additionni Btrenf(th. 

m a circular published a few years ago by the 

ited anchoramiths just named, and exhibitini; 

le Korea of tesiioionies in favor of iron cables, 

foUowiag particulars are derived: — In com- 

theMe cables with the hempen ones, the first 

' plea of advantage is their durability, 

that of the ship itself ; whereas our 

•L ,...>, I utidem generally require a renewal of 

Utter after a second voyage. Another econo> 

il object it presented by the room, which is 

iaarily taken up by the rope, being open for a 

it atowug-e of cargo ; as the chain may be ao 

■a to occupy no otherwise useful space, and 

B left ou deck without injury by eiposure, if 

try. At qoiirs, parts may be applied for 

tooormg; or the cable may lie in the bold, to aaaist 

ballast the vetsel when unladen. The facility of 

ting iron cables has been experienced, as frwrr 

wia are employed; and it ban been ascertained, 

with them vessels can get under weigh by a 

nvini; of at least one-third of the time otherwise 

■ i A more posi(ivc proof of their soperiority 

adduced from the assurances of captains, 

"te»i they have no use fjr their hemp cable. 

iU'h miiy he Uid aside by having a nctmd 

..■■:- iron cable: as the ships in the ports of 

Bn«tol, London, and Liverpool, bear evidenct;. On 

tvcky (round the uicfaoni£« ia effected without 



t&at 



injury to the chain, where hempen cables most bo 
cut to pieces* and endanger the vessel. A nost 
important advantage renults from the carve, which 
the chntn cabtea retain to a very great degree, as it 
fttrcngthens the hold of the anchor by drawing it 
into the ground ; the buoyancy and rontrartion of 
the rope, on the contrary, beiiKng a direct Unefrom 
the ship, tends to loosen and unfix it: and as nearly 
one half of the chain lies on the ground, when any 
scope is out, it yields to tbe tossing motion of the ves- 
sel, and this to a degree equal to any elasticity whieb 
can safely exist in hemp cables. We may. however, 
observe that no elasticity such as is here spoken 
of can be acquired without the loss of strength to 
the material, as the fibres or particles in iron or 
hemp roust be extended, and consequently weakened 
or bruken, to produce it. Into this chain cable a 
certain number of swivels are introduced, at pro- 
portionate lengths, to facilitate the working of it; 
and a shackle is placed in each distance of ten or 
twelve fathoms, the bolt of which ia fastened by a 
pin of composition metal to prevent the corrosion of 
rust ; by this contrivance tbe chain is shortened or 
separated according to circumstances. A large 
ahackle is also fixed at one end to be joined to the 
anchor ; and when required, a mooring ring ia 
attached lo the end of forty fathoms to moor with 
two anchors in harbour. The necessity of handling; 
the chain is partly superseded by the use of small 
hand-hooks ; and to prevent tbe chain from wear- 
ing the wood-work of the vessel, the hawse>bole is 
cased with a wrought or cast iron pipe, and 6tted 
outside with three circular rollers working in s frame. 
It has, in the estimation of sailors, a good appear- 
ance. In 1H22, Mr. Sowerby, of Bishop wearmoutb, 
obtained a patent for a cable chain, with a link 
having a very broad suy or block of. cast iroui 
through which, and the sides of tbe link, a cross 
bar of malleable iron was passed and welded. And 
fur the purpoae of preventing the links from en- 
tangling, there are small projecting parts or pro- 
tnbcrancea on the inner quarters opposite to each 
other. The cut represents thefomi of Mr. Sowerby's 




chain. The next is a chain cnnstruetnd by Mr. 
Gladstone, of Liverpool. The links are first formed 
in the manner indicated by the second rnt, beinf also 
welded at the place where the aides are in contact, 




The link is then bent, and the two circular ends 
brought againiit earh other ; so that when the links 
are roved together, and a cross bar inserted, the 
chain appears as in the figure. 



IMPROVED APPARATUS FOR THE 
HOT BLAST. 
Mr. Pbilips, of Brooklyn, New York, baa invented 
an improved method of heating the air, to supply 
the blast in smelting furoaoes, in which mineral coal 
is used, and in which there is an lir-headng sjipa- 



^ 



309 



MAGAZINE OF SCIENCE. 



1^ 



nitnt Rt tbe tunnri bead. The following ti the de- 
•criplinn ot ihif improTeroent, given by the inventor 
in hn Bpecifieation ; — For the purpose of economising 
furl, it is of con»idfr«ble importance to be able to 
uto ihe WAite beat for flopplying the blast to the 
•rnrltinf furnace, and thii boa been done in numerouB 
invtanrrx, and under varioas modificnlionB of the 
■pparuluB employed. It bai been found, howeTer, 
that in all cbhcs the air >o heated is subjected to 
great varintjon in ita temperature, and tliut from 
canies incident to the employment of aurb fumnceB 
«hrn deprndrnre ia had upon the irastc lifdt atone 
to accomplish the intended purpose. ^\'iuitevcr 
produces a diminution of he^t in the interior of the 
fiimure must produce a corresponding effect in Ihe 
air-heating apparatus, iind that at a time when it is 
mnxt dcairahle to keep up or tiicrease Ihe ttrmpe* 
ratnre of the hot blast, in order the more rapidly to 
reatore the necessary temperature in the fumncc. 
fine <if Ibe moat (jtneral causes of the teni)>urary 
dimiiitiliou of hi'at in the furnace is the introduction 
of the charges of cosi, ore, and flux. The quantity 
of gat cniittrd from the fuel also varies contiderabty 
in dtfTnent stages of its combustion, and with it, 
of course, the ^usntily of flame in the beating ap- 
psralus ; other sources of inch variations of heat 
are fifll known to thofie conversant «ich the use of 
smelting-fumawra. .My impruvcmcni ia intendird to, 
and docs rff'ccttially, obviate this dilliculty, and Uiat 
In the following manner : — On the sides of, or 
otherwise close to, the beating apparatus on the 
tunnel head, I place one, two, or more, small fur- 
naces, for the express purpose of heating a portion 
of air which is to pass from them into the healing 
oven, and to commingle with that arising through 
Ibe chimucy of the srncltinjc-furnace. To these 
auxiliary furnaces I niaka close fitting doors, in 
order that no air shall pass into them, excepting 
that which is formed to puts through the burning 
fuel which they sre to contain. Into the ash-pit of 
these auiiirury furnaces I introduce a pi)>e. through 
which sir. either hot or cold, may be blown from 
any suitable part of the blowing apparstus, which, 
by passing throa^h the ignited fuel, nnd thence di- 
rectly into the heating oven, may be made to com- 
municate a very high degree of beat to the pipca 
contained therein; I of course regulate the suppty 
of air to be blown into the heating oven, and to pass 
from the blowing nppnratus into the anxtliary fur- 
naces, by mains of cock.o, valves, or dampers, ap- 
plied in the ordinary way, which devices are well 
known to nil nmchinists. When it is not requisite 
to employ the heat from the auxiliary furnucti«, by ' 
closing the valves in the passnges leading into, snd 
from them, the contained fuel will merely remain 
ignited, scarcely aodergoiag any combustioa until 
Uf^ed by Lbe blast. 



STRAW PLAT. 
{ Returned /fota pcure t9C) 
Mant attempts have been made to induce the 
English ladies to wear straw hats of home pro- 
duction alone. Bat causes, independent of the 
influenco of fashion, have hilbt^rto prevented the 
exclusion of those of foreign msnnfacLure. It is 
said that thequnlity of the foreign straw is snperior 
to that of thr Englmh, the warm sun nnd morv tceiiial 
climate of haly producing a material which cunnot 
be et|u«lled Imre. The Leghum straw is more sipnder, 
and may thcrefnre be rmploytd entire in the produc 
tion of Uie very Adc articles^ on which account the pUt 



r»*lirnr J 



is rendered roorv even, pliable, and durable than that 
of equal fineness made of spli ' ' ' iitf 

the farther advantage tksi tb'- >rn 

plat admits of ita being join- ul* 

jacent edges together, ihos pr *p- 

tible juncture snd forming -< '-' 

uniform whole. The n»tore trf the 1 
not allow of this, and it is ner«H>«-. 
aod sewed together in an on; 
ridges and depressions, 10 > 
dcrably greatrr quantity of pi 

To protect our domestic ni ■ tn- 

courage the importation of thi .. I'l 

of jt3. 8#. to JL6. 16r. per doxpn, a 
size, ii levied on the importjftlon •■*■ 
this material, e lighter one of 17*. per \> 
pUt nut mode up, and mrrely an ad val 
of 10 per rrnt. on straw not plntted. S . 
ever, is the cheapness of labour upon the < 

in comparitian wilb its rjte in England. tti4 

Hertford.-4bire straw has sctuallj been 
Switierlgnd, platted in that country, and 
to England, where, notwithstanding the ti 
of \7*. per pound, it can be sold at i ". 
per cent, chenper than plat made at home. 

In coosf:quence of this difference of duty m dv 
wrought and unwrought materials, a Bttf^ .. --- 
facturcr a few years since imiHirtrd n c-t ; 
quantity of prepared straw from Leghnrr, 
succeeding in the platting, pincrd it in th' 
Mr. Porry, who first inude himself a pr 
the Leghorn method of platting, and ihri> 
to other persons with so much sucons, 
short time he had above sevrnty prrsor.' 
and children, employed in this manulWct 
diiicloiug the particuUrs of the mod'- -**' 
receivmaa honorary reward from 
the Encoaragvraent of Arts, &C,. whi 
at various times, offered preniium* lor 
ments in the home production and manu; 
straw plat, " influenced by tbe desire <■! 
obtaining employment for tJiepoorin Iheaf 
districts, byconiHbuling to the revival snd imp 
ment of a manufacture at once healthful and 
mestic, and particularly valuable ns acrustn 
children to habits of industry, without the im 
tion of any hurtful degree of bt>dily labour." 

Ac nearly the same time another ran 1 
peared claiming a rewnrd conuTtpd with 
jcct, and which revived the desire of viv*' 
Italians in their straw produoe a« wHl a* > 
maiiufarture. Miss Wuodbuuse, Ihe do 
farmer, rrsiding at Weathersfield in O 
sent to England a bonnet of very fine m 
manufacture, and which, on being aitbuiitt«! lo 
inspection of the principal dealers in such ariirlitr 
was declared to be superior even to L''ghom in tht 
fineness of the mnterinl and the beauty of its color. 
It wns manufactured from a aperies of grau- 
spontaneously in that part of the I'nited S: 
populnrly known by the name of tickle-mf; 
grass is found abundantly la motit of th 
land, but more commonly in fields thai 
been highly manured. Specimens and sreda oi Uit* 
grass were obtained in the hope of promotlnr 
cultivation in England. But little of •.'.. 
however, could be procurril, ai itisnevr- 
America, but springs up luxurtsntly, and i-. 
the time of its flowering until the M-cd i> 
matured. On being sown in this country, i: ,.. -- 
nated very succcwfully, both under cover ud Ui iM 
open air. 



tit* I 

"I 




MAGAZINE OF SCIENCE. 



303 



nifan time manjr exprrimtnU were oioda 
SbbbttC and others on uur F.nglish gruses, 
IDrn put of a most excellent quality wui 
i. The lilt of available ^raisci was cun- 
lnrrfii«rd hj those persons who from time 
lidc rX)M>riiaentf on tbe lubject. and pre- 
lecimrii* (if tbe rtault of thtir labours. A 

1 Hubs of ^ittsn, like tbe commoa Annual 
com, have bat few leavei ; tbe«e gradually 
the sced-itaiki advanre tuward« pt-rfectiou, 
Ir, or ftill ofT entirely, nhen the »cedi are 
ity The f^nusm which are applicable to 
r-plat manufActure are fouad in ibis class. 
he«e, tlie grtMcs which are proTed to be 

uiled to the purpose apprOAcb neAre«t in. 
color to tbe fresb pale greea of wheal : 
men), M the hue recedes from the yellow, 
Mue tirit prrdominnt^s, the deeper snd deader 
es tbe struw become when dried. Other 
ever, are to be considered as well as the 
d theM are not depcndfnt alone on the 
r species of grass. Mr. Parr; found that 
' of gniiti grown upon clayey soils is liable 
10 epottrd or otherwise discolored, and 
0y takes up a larger proportion of iron than 
^reby it is rendrrcd unht to be used for tlie 
Bid of pUt. When rnised upon sandy soils, 
m manner seems to take np ati undtit; pro- 
of silex, Of flint earth, and thus becomes 
too brititc for Ane platting ; but when 
pon chalky suits, as well as bring of a 
color, it possesses tbe pliancy requisite for 
pUt. The re|)UiAttDn which tbe Dunstable 
^ so long rnjoyed is attributed to this pecu* 
^•ing from soi). Tbe mnnner of preparing 
lab graces, as recommended by Mr. Cob< 
f uenrly retemUi's the Italian method. The 
cut as toon as it cornea into bloom, it is 

2 up in small tbeives, put into a shallow 
LeoTcred with boiling water. It remains in 

ttou during tea minutes, on being taken 
Vpread tbiiily on soft gra»s fora week, bring 
ity during chat time. The only part used 
tins is that portion of tbe slalk which is 
tlie upper knot and tlir secd-branL'bes. It 
•r, found necessary in England to cut ond 
e whole pUnt, because if this part were 
while green, it would wither away ; but 
I prapuntion is tinitthed. this as being the 
fat part is taken, and tlie rrHt rejected. The 
hy Mifs Woodhouse did not require this 
I. [n her proocsa the upper part waa taken 
lussly to scalding nnd drying, whif-li opcra- 
IDderwent in ultcraitions, until the leafes 
itb the stem came otf ; it was Iheo moiat- 
•olution of pearlosh and sonp, and in order 
it woa sabjected to the fumes of sulphor. 
jnence of the attention of agriculiurists 
led to this subject, many iuducementd were 
,<o further tbe promotion of so desirable an 
The Highl»nd Sorirty offered several pre- 
I 182j nnd Irt3G, for encouraging tbe home 
tore in imitation of Leghorn plat. ScTeral 
I* appeared for the reward. Among these 
Muir, of Greenock, gave a dftnilcd account 
.manner of cultivating uud prepuriug the 
ich is Tcry idmdAr to thatalrcady described, 
piotis experiments, however, they were in- 
confine tbemstlve* wholly to the use of 
V. dwurfcd by bring grown on poor land in 
leys. Mod not fullered to Attain to sufficient 
for tlie prudactioa of good seed. 



Mr. Cobbett has observed that tbe circumitance 
which recommended the inquiry especially to hia 
attention, was the great advantat^c that this manu- 
facture possesses in not requiring the collecting 
together of a number of people. " All may be 
performed by a single psir of hands — no power of 
machinery is wanted — no other capital than can be 
commanded by any hiboarer's wife in the kingdom. 
The boiling of a pot of water is the sole expeoHs 
necessary to furnish her and her children iilth work 
for 1 part of the winter, and the only engines re- 
qaisiLt- are their fingers." NotwitU^tauding, how- 
ever, all these well-meant exertions of the several 
individuals, the same causes long operated in retain- 
ing Leghorn hats among our articles of commerce, 
and their importation continued in an increaiing 
ratio, 230,000 baring been imported in 18'26, and 
3HI,000 in 181IH. In the following year the qnan- 
tity woa reduced more than one-half, owing princi- 
pally to a change of fashion; and in 1832 th« 
number brought for ust; from abroad was onlj 
GO. 830, The straw selected for the pnrpoae of 
making hats and bonnets in this country is cvery 
year improving tn quality. In different specimena 
which were exhibfed in 1825, those prepared from 
spring wheot were pronounced to be decidedly tlie 
beat, atid very superior to any preceding specimena. 
But grufises ure still con^iidered to be very useful 
miiterials. By tbe careful cultivation of those 
which are more peculiarly adapted to this purpose, 
a constantly improving nalerial is being produced 
while grcuter skill ia displayed in the manner of its 
preparation. ijtraiAiay not be obtained sutflclentlj 
slender to produce a very fine plst without being 
split, which gives to the English hats nearly the 
same durability as tbe Italian. 

H«ts are likewise fabricated of chips or thin slips 
of wood. This manufacture preceded that of straw 
plat in Englnnd, though it would aeem to be less 
obvious and natural. The trcea whirti are moat 
appropriate for tbe purpose are the lime, tlie poplar, 
the willow, and aome others, the wood uf which is 
white without knots. W'Jiite the wood is yet greea 
it ii divided into very fine chips ; this operation ia 
easily performed by means of a very simple inatru- 
ment, a plane with two irons. The tint of these ii 
provided with several teeth, tbe width of which ta 
proportionate to the required fineness of the chips; 
tbe second iron, which followi tbe first, has a com- 
mon plain chisel-edge. On tlui plane being passed 
over the wood, it is evident that the shavings will be 
divided longitudinally into aa many slips, and one 
more, as there are teeth io the tint iron. That the 
teeth may be mode to repass always over the aame 
spot, the plane is pushed between two guides, by 
which means it is kept steady in one direction. 
Several macliinea have from time to time been in- 
vented fur dividing tlieae chips, hot this double iron 
plane is the simplest, and perfectly sniwers th» 
pnrpoae for which it was intended. 
(To be amtiim^J 

MR. PATRICK'S RULES FOR JUDGING OP 

THE \VE.\THER BY THE BAROMETER, 
Th8*^f. arc e*tecmed the best of any general mica 
hitherto roadii.— I. The rising of the mercury pre- 
laws, in general, fuir weitlher; and its falling, foul 
weather, as rain, «now, high winds, nnd fttorms, 2. 
In very hot weather, the falling of tbe mercury in- 
dicalea thunder. 3. In winter, tbe rising presages 
frost : snd in froacjr veatherr Lf tbe meruor; falls 



MAGAZINE OF SCIENCE. 



p 



thrM nr fuur dwUlunt, ihere will ccrtiinlf rollow ■ 
tlt«w. Hut in R cnnlinunil front, if the inercarjr ricri 
It will rrrtninljr *n<iw. 4. When foul weather hip- 
ii^ni loon iRi^r th«> f«IUng of the mercury. ex\tvt\, 
but little of itt aiitl on the coulruty, espect but 
lUUe Ulr wr«(K«r when it provu fnir vhurtly aflcr 
Uia mrroury hu ritrn. .'i. In foul weather, when 
tht mercury riwi inqch and high, and la continurA 
for two or three day befurr thr foul wmthrr U quite 
«wr, thvn MprTt a ronlmuancv of fair weather to 
follow. 0. lu fatr weather, wSeit ttie mercury falla 
muck and low, attd thua coiitiuues for two or three 
day* brftiiT ih»« rain comri*. then expert a great 
deal of vet, and probably hi^h winds. *. The un- 
Mtclcd motion of Ibc merrury denotes uncertain 
wad chancTtablc weatitrr. 8. You an? not &o strictly 
to obaorve the wordi engraven on tlie pUtci, u the 
nereory'i riaing and falling; ihutmh in gracnl it 
will airw with tb<'in. For if it ■taada tt mvA 
rain, and ibcii nae« up to ckaafeabie, it pT»in«a 
fkir wratbcf : tfaottgli not t» coMinua lo long ai if 
Ibr m«re«ry bad rtiMi lii|b«r. Aad ao. on tlta 
OMitnrT. if the ■wrcurj gttmd at lair, and CalU to 
ckangfahle. tt pwaagii ImiI ««ftikcrt Jwigh ■*! 
•• «ttBk «f il » if H kad 9mk low. 

Vfmk Itow raba af Mr. htmk tte Mlavi^ 
fMMn»«« mrn^ky Mr. K — m i a g ; That hit mi 
•a mk t^ ahnhAa Inigibt of iW ww iwj ia tW 




»«M(l»r 1^ m mtmf it irwjl| rida^ag CaUM^; 
Ik «4k4 ««4 Ik* MavtaiC vvtB «M af wmz — 

MtWMifta MddlB «f Ika tote tkaa «tA««iai. 
ii ik a «^ tkai ik» totoMvy la itea !■!■$. t. Bik 

Itbtfca^^li^. A*d. X If lltorW^«r 




^^ liMpk 
llw 

^ VMM valka 
M af a «n»k to 

«f (WKrokea 
r^ly prvduf^d 



the churn u not a large one, • donlciry aod nniU 
cart will answer the purpoae auffictrn'"- --'i Mr. 
Oabonie, Dalacone, in whoie dan gf 

churnutg ia pnraiied, employa a im - ^ ^15. 

form the work, which ia driven along the hisa toad 
until the butter ia produced ; and an odd-luoLiag 
a(r4ir it certamiy appear* when It strikea tUc nooa 
of any passing triTeller.— />Ufrf/We« Cutaitr. 

Ltjfht/mm Stalf M*A. — Dr. Hulme hai ntl^ 
liahed that the quantity of light emitted by <ka4 
aiiitosl iubklances, is not in proportiun to the dsfito 
of putrefiiclioo in them, as ia eummgnly auppOMd; 
but, 00 the contrary, the greater the putracntev^ 
tlie less liKht it erulTcd. It would iecm, that ikil 
clement, endowed with pre<emineut rtsattaty, >« th« 
firat to escape from the condensed state of > 
tioD, in which it had been imprisoned by t;. 
of life ; and it ii followed, after some tiuir. ui >.n 
rdatirrly leva daalie gases, the evolution of whiefa 
contnbntes to paitrefactioo. — Popular Brron. 

T%t W—l ^ the Lmma.'^K gcnileraan of tlit 
■aae of WooUsteo, who has resided for some j0tt 
aau^ the Boaatains of Thibet, has lately discoveird 
• tfKOm tf iha Lane, the color of which is per> 
fcetir Uadu Mid iu hair u soft as dlk. Aaasupl« 
CMarM^y. W atates that it does not poaani tkf 
pi apmii i of wol, it being much more fine thaa 
iatWhtteg ■i l ii i al; but it would admirably «tU 
ant lh« tea ika»i trade, as it is carried on ia lU 
of ClMgow and Paisley. The hain 
twdre incbca in length, sad 
af a jrt hkak csbr, so that they do not re<|iilT» 
a darker abade. A larger aaaa* 
mj of Mamt^^iA haa b«co turned ia theailK 
up by the French ma* 
asd aent to France, whart U 
at m*ck as from \2m. Cttt. tu Hi. per 
raw anspaa material h^i m<': ■ 
at 2a. CdL to 3s. pv powid. T' 
hawaJvafa Ibtdied hi«ii 
«f t stttiUr descr 
aad iK iaaotataUimpToba) : 
•Ok; hair of tW " Alpaca.' .> .. 
Ii toort Ibsc^ W ^ Cashmere weaTcra In ibcu 
«f the bDer very valuable aa well « 

. — TW Adiowing nbatitvta ta 
MSB saggoalcd in the decor 
of Fhrliaaait, nhirh, it ie 
eqm'l^ beautiful cff«-< 
TW vaU if t\i»t cti\' 
t, eonsMMly caUcd aiuceo ; 
la dry. ir must rerrivr ihraa or four coats >' 
■vraf fat tmaeed oil boded with gum. m 
fact, it may ha called vamt&b. ' 
that it will not emk. Th» pm*"' 
t. and keeps it from what is t«ri 
cover wiih the grooad for Uk 
the color with half tttrpentuir. 
f^anr itself, hate your colors ground in 
work them in turpentine, and ic will have i.- 
effeet aa ftvsco painting. It rrf|uirea to be tiuuiud 
npeditionsly. av the colora set rksL Tbia MJrt rf 
patoting. I should say. would auwer well : liC- 
Because it will dry hurd. 2od. It will rctaia 
color. 3rd. It is equal to fresco in beauty 
appearance. 4(ti. After preparing the wallk, 
rootiifl may he u»ed for boaincss, and the artisU 1 
tinue ihrir labours at Kuch times as are 
temeni, as there is but little or no diit. — AU 




OnM Hwia U^ . Mj|aJiori -Pui>hihgd by w. Bsittaii!. il, fst^mstu 



30G 



MAGAZINE OF SCIENCE. 



(Tv the HiUtof.) 
Sir. — I have endruvoarc*! to perform my proraisa 
of eiviiig 50U tho drawing:, nnd I hope an irttclligiblo 
df»*riplinn, of m rtrj lutrful hiitrumcnt, oqc much 
approved of by all I bave ahowii it to, who orHler- 
ftAnil drawinjf ; it Htmy be miJr nt a cost of about 
If yoti think it worth n pliice in your Maga- 
\c, malte any alt/iracton you lUink proper in Uio 
lani^ni^e ; as, donbtlrss, you witi find inmr. parts that 
Ttqnirr amrudmcnt — my object has been to give 
eucb a deacription u to enable any person to make 

it. JAMES WILCOX. 

[We give the description entire, at written — bd.J 
WILCOX'S FKRSPECTOGRAPH. 
Av instniment of perfect simplicity ; it requires 
neither staod to hold it, nor eye>hole to look through 
— mrrely iuspendin^ it to the nrrk iriHurfs its return 
to the same position, and when not wanted to be 
consulted, hangs by its string, without the least 
possible ioconTenif nee ; even thn most practised in 
■ket(?hing may derive assistance from it, aa it will 
determine the vaniiihtnu; point for them in an instant, 
and mtasQre unerringly all the proportions. 

With this instrument, any person may draw 
buildings correctly iu perspective ; it is equally ap- 
plieoble to landscape, and is also of great use in 
copying pictures. 

No. 1, is a view of the perspecto graph, partly 

lened to show it more completely ; it is made of 
two rules of brass, 9 inches long, and about j inch 
wide, one of which his a stop, to allow an arm to 
■lide in it, — they are screwed together at 3 inches 
from one end, which screw has its bead formed into 
a loop or eye, by which it is suspended to the neck 
by a string, when in use. 

No, 2, rejirescnls the manner of using it; the 
person bt-ing suppoRed to have set it to the foriu of 
the outline of a building, and in No. 3, to have laid 
it down on the paper, and ruled off by its inner 
edges the form of the house. 

No. i, another object being seen through it, and 
transferred to the paper. 

It has a silk cord with a hook at each end : this 
cord ift the greater port of its length double, and 
tied into knotjab«iut an inch apart; one end k hoakrd 
Into the eye of the instrument, the other put round 
the neck, and hooked into anch of the loops in the 
string as required. 

The rules to be observed in sketching, are : — Ist. 
The paper and the instrument must be of the aHme 
lengthy the height is of no consequence. 2Qd. 
Having determined on the quantity and base line of 
the subject, put the string round the neck, hold the 
Snstrumeac level across the face, at such a diiftanue 
from the eye, that its two cnd« just reached tu the 
extent you wish to mslce the skrt^rh ; then put (lie 
hook into that loop that will retain it at that distance, 
particularly noti.:ing two objects then at its ends, to 
be guida for all future reference. 3rd. Observe 
nndrr every oircomstance of using it, it must be 
held square to the subject, or ita result will be 
deceptive. 

Manner of uttnff it. — When thus held up to the 
extent of the string, the position of every objfct in 
the lanJscnpe may be correctly noted down by its 
diviaiuns and fifEures ; now open it to a ri^ht angle, 
keeping th«- baac to the position first determined on, 
snd the perpendicular side gives the correct height 
of all the objects. 

Drmping Buitding». — While (he perpendicular 
marks the uprighti the base of the angle may be 



I bent to the inclination of the bottom of the boilditig, 
and the ahding arm to the lop ; hti- "' Ic lo 

til the outline, unhook, lay it on i> the 

pencil bf-ing run along its Inner ■• ^ 

correct outline m true perspective 
by repeating ihia, all the different r 
ore B8 easily obtained, and the distdtico of |>ilJ«(«, 
windows, doors, ^., being shown by the figures. 
By reversing the ends, it becomes a foot rule, ths 
figures being marked each way from the centra, auj 
is thrn applicable to a larger paper ; if openrd ts 
the uorrcicpcinding lines at the bark, a right ailgtt M 
found, and a T ^uare is produced. 



ON THE MANAGEMENT OF BULBS, 
BOLBS closely resemble buds in their structarv, it 
well aa in their functions, ond differ chiefly in boag 
under-ground, and of course out of light ; wtdk 
buds are not usually under-ground, and are mose* 
quently exposed more or leas to light. Some balbl 
are of dose teiture, as those of the tulip and snow* 
drop, while others are more open, aa thoae of the 
white and the orange lilies, thence termed tcity 
bulbs. Ilulbs may be classed, first, under hc^f, 
requiring no shelter ; seoomUy, as hatf-hanl^, n 
quiring some protection from cold and wel 
any arti6cial heat ; and. thirdly, as tender, 
more or less artificial heat. It is the colti' 
the first sort that we are about to describe 
will endare all weathers without any artificid 
or protection, and may be easily managed 
obserring the following directions : — 

Soil and Seed SoH'tng. — The soil most 
to the growth of bulbous roots, in genemi, ia 
B sandy loam, where there ia no stagnation 
ture below. Many sorts of these roots ai 
however, very difl^ult in this respect, p 
there be not an over- proportion of moi»tare. 
ground for them should be prepared by digging ft 
to the depth of from six to eight or ten incbrs ot 
more, reducing it well in the operation. After ifaaf 
has been done, it should remain a week or tea days 
before the bulbs urc put in, to become perfrctfj 
settled. Seed shuuld be carefully saved d 
best and most curious flowers, and when 
ripened, after having been hardened a little 
sun, should be sown in boxes of light rich 
setting them in a sheltered sunny situation, 
under cover. This is Uftually done about tl 
end of August or the beginuing of tlic 
month; large sorts being covered to the 
nearly an inch, and smaller sorts half an 
little water should be occasionally given w' 
season is dry, lo keep the soil moist, but not 
The seeds may be protected till they come 
little covering of some kind of strawy- 
Other sowings may be made in March, or 
lowing month, the boxes being brought into 1 
exposures, when there is only the mo 
towards Mny. 

4/ller f\Iture of Seedlimgi.—TUe rooog 
plants shonld Iw protectc^n severe frosty 
and when there is much rain, by means 
and hoops, and a reed hurdle, or other conti 
to break off the north-east winds. The young pi 
should likewise be kept properly thinned out, 
perfectly free from weeds. When the stems 
a lillle mould should be put upon them, 
thickness of half au inch. In tiic fallowing 
when the le^vi-s decay, as about August, 
be plooted oat ialo aortery-beUs, ac iha 



MAGAZINE OF SCIENCE. 



307 



irae inches, according to the kinds. Som« 
■aire to be removed from these into other 
!di u toon as their tojii decline, and vet 
:bu distance ; or it ia probably a better 
to thin them out to this distance in the flr«t 
kfter this tbry are to be iiianaged aa blowing 
S. These aorta of roots blow at dilTerent lengths 
oe. after being raised, some in the first, some 
e folloirtng year, and others not till seTenil 
■fterwards. In all such plants a store of pre- 
I pulp ia laid up in the bulb each season, for 
Icing the stems or flowers the succeeding 
D. It is clear then, that the more palp there 
>r«d up, or, in other words, the larger and 
sr the bulbs are produced, the stronger and 
~ the Items and flowers aAerwardia grow, 
[.flowering and fruiting ethoust the pulp, let 
rer in the seedling be pinched off in the 
ley offer to blow, while the leaves muat be 
le stem to prepare pulp fur the root store, 
ruke larger flower-budd in the centre for after 
ng. In this way finer oiid larger bulbs can be 
tc«d than in any other way. It injures many 
, however, to break the flower stem, as would 
D Cftse, for InaCaiice, with respect to tulips. 
If^ation by Stem Bulla. — Some species, such 
B tifer lily, produce on the sides of the top 
of their steriiA, at the inner base of the leuves, 
dtrk colored bulbs, or buds, if they may ho 
d so, from which young plants may be raised, 
tcm bulbs should be tiiken off in August, and 
iwing dried for a few days in the aun ought to 
hftted out in rows in the same manner aj the 
; offsets from the root bnlbs. 
frovrmerU qf Butbt hy Drying, — It ia im- 
kt to notice here the periodical activity and 
'' plaats. it being necessary for their health that 
ibould have intervaU of repose succeeding to 
7, no lesa than sleep is needful to ammala. 
;ioiu processes of artificial management, the 
■k or extending this period of repose is 
Km produrtive of very marked effecta. By 
PpLuits in a state of repose sooner than 
d, they can be brought again into active growth 
' than their accnstomed seasons; and by 
g it more complete than it can be made in a 
of nature, the plonta may be made to awake 
;realer vigour. With respect to bulbs, their 
I of rrpose commencca. as In other plants, 
:he withering of the leaves ; and as complete 
\ eaunot be induced when the stimulus of 
tre is preafnt, it becomes necessary to take 
lbs nut of Ihr ground. As soon then as the 
sorts of bulbous flowers ore ps&t blowing, 
le leavirs beginning to die off, the bulbs should 
leu out of the ground, choosing dry weather 
J pnrpose : and they should be gradually and 
Lglily dried by eprending thum out and luniiug 
Co prevent the appearance of mouldiness or 
r. It is also important to cut off the.tlower 
juit before flowrrins, to place these in water, ' 
ow them there, allowing tbe leaves, as alrcjidy 
Dcd in the cultivAthm of seedlings, to remuin 
\ ]Mirpo«e of nourishing the bulb. But it is 
i«l ilic bulb will be apt to canker and rot, if 
»-.T 5t-_-tn be rut down after blowing, while it 
I tr li. and before it dies down. There is 
ipte, which is usually overlooked by 
xs and practical men, for inducing a 
• <'f r.'9t in the dui:-up hulb^ ; and 
of light. Uulbd, like bU under- 
r:rudu;:tiuDS, djalikc the bght, and 




hence when bulbs are planted too shallow, they do 
not blow so finely as when deeper in Uie ground. 
Hence it is fairly Inferred tliat light has, lo speak 
physiologicully, ratbcr a sedutive than a itimnlant 
effert on bulbs; consequently, by placing the dug- 
up bulbs in the light, and not shutting them up la 
boxes and boskets, as most florists recommend* 
must induce a more complete state of reiKisc. Be- 
sides, by carrying off the supcrfluouB water from 
the Etored-up pulp, it tends to enrich its nutritSro 
properties, and this also is best eflectcd in the light, 
which )>romatrs cvapomtion aa well as decompnsi. 
tion. Tbe natural period of repose for most bulba 
is six weeks, or two months, bat many sorts may 
be kept out of the ground deveral mouths, and 
some sorts admit of being kept out of the ground 
from the time tbe flowers and leaves decay till tbt 
following spring, as is often practised, to obtain a 
longer succession of bloom in the flowers. Bulba 
of the coated or laminated kinds, such as lilies, 
should not be kept out of the soil longer than six 
or eight weeks, the summer flowering surta being 
act at separate periods in the autumn, and in the 
beginning of the year, before tlie latter end of 
February, so as to produce a succession of flowers. 
With others of a more delicate nature, this method 
is also common, but they should have a dry landy 
soil, in order to stand the winter without rotting, 
where there happens to be mnch wet, succeeded by 
severe frosts. When bulbs have remained in the 
ground longer than the proper period, so as to have 
struck out new roots, they should always be removed 
with bolls of earth, as where this is not atteoded to 
they grow weak. On this acoount the exact period 
for removal should be carefully obaerved. It U 
necessary, on taking up the choice kind of bulbooa 
roots annnally, to srpamtc the offsets for increase, 
ai well as to prepare the earth of the beds and 
borders afresh, to promote the fineness of tbe sue- 
cecding year's bloom. The inferior sorts of bulbooa 
roots should also be removed every other year, or 
as often aa their ofl*scts are considerably increased ; 
for when increased Into large bunches they cramp 
each other in growth, and produce small iil-oou- 
rishcd flowers. 

Planting out and j^fter-eultyrt, — With respect 
to the aeasuna for pliuiting out bulbs after proj>er 
drying, it is recommended aa the best practice to 
plant tbe spring kmds in the beginning of tbe 
autumn, such aa in tbe latter end of Srpteinber, or 
beginning of tbe following month ; and those of the 
summer flowering in October, or the beginning of 
November ; and those of the antunm blowing ia 
the latter part of July, or in the following mouth i 
Luu early nod loo late planting being eqtully to be 
avoidod, as when put in too soon, the flowers are 
liable to be injured by being too forwurd if the 
wiutcr and early spring prove severe ; and when 
delayed too long, they are apt previously to cibaust 
themselves by forming roots. The offaeta of bulba 
should in general be put into the ground a consider- 
able time before the periods of planting out the 
full-sized roots; tliose taken from coated or lami- 
nated bulbs mostly requiring to be immedUitely re- 
planted. With respect to the disposal of bulba in 
pUiititiz, the Larger and more choice sorts require 
beds a littlt- rounded, of three, four, or more feet ia 
width, according to circumstances ; the smaller 
S4)rts apjteor best in patches in the cumuiun borders, 
in cludterei of three, four, or five together, acci^rdiug 
to their respective height. With tlie l.ugc sorts, 
ouc in a phicc ia auUicitut. The fouvy auit of bulbt 



303 



MAGAZINE OF SCIENCE, 




wbcn plinted in beds ore usaallf put in rovi eight ] 
or nine inches ipart, and from five to fievcD inches 
distsnt, in proportiou to their bngbt. Some prefer 
less room, but where & strong blow is required theae 
diitances are not too great. The depths of utting 
bulbs are in general according to their litea or 
frowths, u three or four inches from their upper 
parts, though some sorts «riU rue from a consideruble 
depth, tu six inches or more, and others from still 
greater, which 1ms induced some persons to plant 
them to such depths as are sufficteat to prevent 
tbor being iojnrcd by digging over the surface 
ground. DiH'ercnt methods are emplujed in plant- 
ing bulbs, such as putting them in by the dibble, or 
in drills drawn by a hoe. The latter is in general 
to be preferred, as they are apt to be hollow in dib- 
bling, whiln, by placing them in a drill they may be 
gently pressed into the soil, and be perfectly corered 
up. When they are set in beds, the best method is 
to draw off the mould of a sufficient depth to one 
side, leaving the surface perfectly level, watering it 
a little in dry seasons, and then forming it into 
proper sqaares, placing a bulb in the middle of eacht 
and covering them with the mould drawn oT ao as 
to leave the bulbs in on upright position. After the 
bulbs have been put into the earth, if the weather 
continue very dry, a little water should be sprinkled 
over the beds or other places, to forward their 
vrgetatioa and prevent their rotting. Occasioaal 
]>rotection will be necessary in raising the more 
choice sorts of bulbs; and before they appeu*, 
during the winter, the beds should be sheltered from 
too mneh wet, in order to guard against the effects 
of sueeecding frosts. When tbey first present them- 
selves above the ground also, they should have the 
protection of an awning of doth, mats, or other 
Contrivances at night when the weather Is severe ; 
but these should not remain on In the d»y time 
when the weather is tolerable. Some sort of cover- 
ing of the same sort is likt^wise necessary when they 
are in bloom, to shield them from the sun and rain, 
and continue them much longer in & perfect state 
of flowering. 

UNCERTAIN SIGNS OF DEATH. 

The cessation of pulsation In the heart and the 
arteries, and coldness of the body, are commonly 
thought to be certain signs of death ; but the re- 
searches of science have proved them to be very 
fitllariona. A more certain sign is the suspension 
of respiration, for it cannot be continued many 
mtDutes without actual death superrening ; whereas 
the action of the heart end arteries may be sus. 
prnded for a considerable time, if rrspirotion be still 
carried on, however f>b»cnrely, and yet these organs 
be again awakened to activity. The 6rst object,, 
therefore, in supposed death, is to ucertaln whether 
respiration still continues. This can, in mony in- 
stances, be perceived by baring the thorax and 
abdomen ; since it is impossible for breathing to be 
carried on for many seconds without the inHuence 
of the respiratory muscles, the effect of the action 
of which la to elevate the ribs and depress the dia- 
phragm, so as to push forward the sternum, and 
cause a momentary swelling of the abdomen. It is 
of jreat im]>ortnnrd to the young practitioner to 
accustom his eye to jud?e accurately of thepe mnvr- 
tnents, as the ordinary mi'tlnKii uf applying a mirror 
to the mouth, or a downy feather near it, are both 
liable to error. If the mirror be warmer than the 
expired breath, qo sign am be obtained by it, 



because the breath is not coodenn^d upon h : or, the 
iosensihle perspiration from the fland of htm who 
holds it may sully its surface ; whilst ** the li^t 
and weightless down," if confided • "■'' '-!-;4a 
more than the prince, who is thos d- ^v- 

ing been deceived by it, when cu ; ^ tM 

crown from the pillow of his royal father : — 

"'Ity hli gale* ot brsiilh, 
Tlirfp lici a dowoy IcxUier. wKicb tlin not ; 

[)j>l iK' rft}>lrF. Uml ll$bl sad wtigliLtcsi dowa 
Pcrclinnrv touvt mvvw." 

Another symptom, the opsdty and want of Instrt is 
the eye, is c<iually fallacious ; even the Chin slimy 
membrane which covrra the oomea in the eye of 
the dead, which breaks in pieces whea loucbed, sad 
is easily removed from the cornea by vHpfng, mom- 
times is formed many hours before death has oe* 
curred. In several mstanoea, also, this appearsiKC 
does not present itself even after death ; as, fat 
iuBtanee, in cases of poisoning by hydrocyanic add, 
in which the eye retains all its luatn; for hours after 
death ; and the irts even contracts when approached 
by a bright light. This sign, therefore, when talsa 
alone, is of no value. — The stale of collapse, wbiefj 
is one of the symptoms of cholera asp))- 
demonstrated how little ia the valae of 
the body as a sign of death. In that singular uis- 
ease, the coldness which accompanies the Hal* ot 
collapse ia that of ice, and during it no T...i-.ii.i^ 
can be perceived, even at the heart ; yet ' 
lives and breathes, and frequently recovers, 
persons, also, in whom animation la only su>peiidnl, 
and who may be recalled to life, are always cold: 
whereas in some diseases, apoplexy, for example, • 
certain degree of warmth is |>crceived for maey 
hours. — Paleness and lividity of countenance slwsys 
accompany the above state of collapse ; the body 
even becomes bine: this »ign, therefore, which k 
usually set down as one indicating death, is of !«■ 
value than any others. Cases, on the other band, 
hare occurred in which the coontenance hu t^• 
mained unchanged a conslderoble time aft«r deadt t 
and in some instances, as Dr. Paris has remat%«d( 
** its color and complexion hare not only beM 
preserved, but even heightened :*' as if the rphift* 
scorning the blow which severed it from mortalit}, 
had left the amilo it raised upon the movilai 
features ; or, as Shakespeare would express i(t, 

" Sinilino, aa totat fly had ik-klvd slumber; 
Not at Ueath I dart, b«lO| lau^'d at" 

From these, and other observations, by the UOHt 
writer, Dr. A. T. Thomson, it is evident, that ihas 
are no certain signs thot a person is truly dead, 
except the total cessation of respiration, and tkf 
oommeaciug putrefaction of the body. 



STEAM AND THE STEAM ENGINE.. 
( HtMunttd ftvm p«ge tM.^ 

Soov after the time at which De Cant ptibHil 

account of his contrivances ; namriy in 161 
scheme was given by an Italian architect and 
gtueer, named Branca, which exhibits a 6if 
mode of applying the agency of steam ; in thil|l 
impulsion on a wheel prodnced a rotatory Bobf** 
The following cut abowd the picturesque Np|HtfS)al 
he hai given to iltnstratr his invention. 

A ia a boiler with a negro's bead attached ; 
the mouth of the figure issues a tube, and vi 
fire ia placed betteatli the boiler, the st£i 
from tbe tube, ttrikei ngmMt tbe flo«l-b«Hdf< 



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MAGAZINE OF SCIENCE. 



309 



tiul whrtil Q, To the tpiiiilleof B h attachrd 
jndle (', which works the coggrd wheel D, 
tU mrnnii the crank And pump rod E. In 
^iitiil it wtu maile to move stampera uj> and 





were placed to be poanded. A ilight ia- 
tD of firanca's diagrnro will convince oi, that 
Mrlet of wheels, and the stninpcrs and mortars, 
introduccJ more to show how steam may be 
Applied, than that it ever was so. His buck besides 
redlj a collection of mschines invented by 
and ihii mode of tDoving a wheel by steam, 
fcbly, therefore, an idea of which he is the 
iUoatrator. If not, it is only a slight modifi- 
of the older CElipiles, and has no connection 
rer either in strncture or principle with the 
eogioe now in use. Branca gives another 
in his Toluroo, in which he shows the Mmoke, 
1^ through a pipe from a tmati smith's forge, 
Aioving a wheel, which commoDiratcs motion by 
wheels to cylinders, for flattening iron bars. 
by the smoke and that by the steam, may 
'»re be equally efficient; and both, probably, 
imilor pretentions to being considered as never 
been applied in practici;. The pictaresqne 
lent of his nppnratus will be rradtly od- 
as a proof of the position, at least, that 
Iratica was a man of taste, as wcU aa a person of 
ingvnaity. 
The year following that of the publication of 
tea's book, the ingenious Cornelius Drebbcl, 
has left so great n reputation fur ingenuity, 
few of whose works remain on which it was 
led, put in practice the device, which has been 
il)ed as producing the sounds of the " Egyptian 
Idol ;'* a musical itutrument, which being set in 
th« sunshine, would of itself render a soft and 
pteuanf harmony, but being removed into the shude 
would presently become silent. The reason of it was 
this: — The warmth of the sun, working upon some 
rithin it. and. rarefjing the inward air unto 
it an extrnpioii. that it muftt needs seek a vent 
ifice, did thereby give several motions to the 

lent. 

tsidering that the Marqois of Worcester really 

proctiott all the wonderful contrivances men- 

io his " Century of ln%'entioni," we shsU 

ind to cede to him the reul invention of the 

f ugioe : for, until he showed how a recipro- 

aciioo was to he kept up, there was nothing 

eould claim to he so considtTed. With this 

'f public character ffc huru noihiug 



^mot^iauj] 



to do ; though his career wai cheokored with casual- 
tiei, hid conduct appears devoted tu his royal master 
Charles — in whose service hia family were eiti'rmi- 
nated ; his cnstle (Kagland Cn&lle) besieged, taken, 
and destroyed; himself reduced to dextilutiDn, op- 
pressed with di-bt, and without resources. During 
the ascendancy of the parliament, he mostly re»ided 
abroad, but coming to London with a commission 
from his royal master, he was token prisimer, and 
for many ycon confined a close priiouer iu the 
Tower. 

The tedium of his long imprisonment was be- 
guiled by mechaniml amusements, which, it is ga- 
thered from other Boarccs, he diligLtitly followed 
even in the times of hia brightest fortunes, and in 
situations apparently the moat unpropitioua for hia 
being able to spare the necessary leisure and atten- 
tion. At his eolnrgcment, neither tiie dihipidation 
of hia fortune, the love of pleasure, which wai 
strongly implanted in him, nor his own inrreasing 
inlirmitiea, had auy effect in damping the ardour of 
his enthusiusm. 

Tbc desire of being useful to his country, in the 
way which his experience pointed out was of nit 
others the most effective, gained strength aa \ih ofTera 
of service were rejected. Yet ho solicited but for 
that cheapest of all patronage, the countenance only 
of men in power, to ensure a fair trial for his in- 
ventions ; for notwithstanding hts deep embarraia. 
ments, so aanguine wai he of the practical value of 
his projects, that he offeretl to make all the cxpcri- 
menta at his own expeuse. The passage is curious. 
" Be pleased," he says to parliament, " to make 
use of me and my endeavours, to enrich them not 
myadf; such being my onely request untu yon, 
Sparc me not, in what your wbdoma shall find me 
Uflcfud, who do esteem myself, nut onely liy Che act 
of the water-commanding engine, (which so cUear- 
fully yOD have past.) sufGcieotly rewarded, bat like- 
wise with courage to do tea times more for the future^ 
and my debts being paid, and a competency tu live 
according to my birth and quality settled, the rest 
I shall dedicate to the service of our king and 
countrey by your disposals ; and esteem me not tlie 
more, or rather any more, by what is post, but wh.it*s 
to come ; professing really from my heart that my 
intentions are to outgo the six or seven hundred 
thousand pounds already sacriAced, if countenanced 
and encouraged by you ; ingeuoujily confessing that 
the melancholy which hath lately seized upon me, 
(the cause whereof none of you but may easily 
guess,) hath, I dare say, retarded more advantage 
to the public service than modesty will permit me 
to utter. And, now revived by your promising 
&vours, I shall infallibly be enabled thereunto, in 
the experiments extant and comprbed under these 
heads, practicable with my directions, by the un- 
puralled workman, Caspar Kaltoff's liand, who hath 
been these fivc-and-thirty years as iu a school under 
me employed, and stiU at my disposal, in a place by 
my great expenses made fit for public service, yet 
lately like to be taken from me, and cont^cqaently 
from the service of king and kingdom, without the 
least regard of above ten thousand pounds expended 
by me. and through my xcle to the coflomon good." 

The book to which be alludes, as containing the 
" heads" of his experiments, was published in 1G63, 
under the title of "A century of the names and 
Fcantliugs of such inventions, as at present 1 can 
call to mind to have tried and perfected, which, my 
former nob's being lost, I have, at ibc instance of « 
l>oworfat frieodi endeavoured, now in the year 1655, 



310 



MAGAZINE OF SCIENCE. 



tet down in such h. way, an may sufDcieotly iq" 
itit me to pot any of them in practict*.'* 

The noyelty of the greater number of the hun- 
dred propositions or descriptions of which thia to- 
lume cooAUts, &nd the wonderful nature of others, 
cut an air of improbability over the whole ; the 
^ohle author was rbargrd with dR^tcrihin^ many 
' ling« which he wished were inventpd, rnther than 
inachineft which he bad actunlly constructed. And 
even thoHe who have been warmeat in praise of hia 
l^nias, and hxT« apokeain faTomble terms of some 
of hit ** scantlings," have found it nocessary to 
enter their prote&t against others, in order to tiTe 
their own conii«tpncy. 

Yet t!ii« rollprtion of descriptions bears internal 
Toarlcs of bcin^what it professes to be. drawn up 
from actual trials of machines in existence. On an 
attentive cxuminadon of the genrral icope of hia 
ioTenttona, they will appear to have been su^ested, 
thegiTuter number, by the wants of his accidental 
tduiation, and a small number by those of his station. 
To a statesinan employed in hi^^hly confidential ne- 
gociations, the secrecy of his corrrspcindenrc would 
be of great importance ; to a traveller the security of 
bts locks ; a soldier is mainly interested in hia arrai, 
at limes in scaling a fnrtifiratinn.nr transmitting in- 
telligence in the dark : and the projector of a water* 
ooaipnny could not fail of layiug hii ingenuity under 
contribution, to devise a mode of raising water above 
ilB level. These classes comprise the greater part 
of his hundred inventions ; nod whfn we learn that, 
for so long a period as thirty-five years, he employed 
an expert mechanic in his various prujrcts, it is a 
matter of wonder that his invrntionn were not more 
nuaemuB. .\nd in fact, he saye that they were so; 
for he observes, " that he baa omitted many, and 
some of three sorts not willingly act down, lest ill 
be made thereof ; " but that such Ihingi were actu- 
ally within bis knowlnlge is quite clear, for he pro- 
mises to "set them down in his own Hpher, not 
to be concealed when duty or affection obliges him.'' 
It is also very generally admitted, that not a few of 
his improbable things are trifles, while others usually 
conceded to him as conveying clear notions, are 
decidedly machines of importance; and all are 
agreed, that since hia book was published, many 
similar conlrirances have been put in practice. 

There is nothing therefore preposterous in the 
opinion, that nil the inventions described in the 
*• Century," had hct-n put by the noblr mechanic to 
the test of experiment. Of one, which is the sub- 
ject of the sixty-eighth proposition, we have for- 
tunately very conclusive evidence of itn hating been 
ttc/uatfjf ervcted, and this may be considered as that 
one the mnst obscurely hinted at, and described as 
capable of the most improbable performance of alt 
his inventions. Tlie announcement is as follows:— 

" An admirable and most forcible way to drive 
Up water by lire, not drawing or sucking it upward, 
for that must be as the philosopher callelh it, ip/ra 
irjikttram activitatia, which is but at auch a distance, 
but this way hath no bounder, if the vessels be 
strong enough ; for I have taken a piece of a whole 
cannon, whereof the end was burst, and filled it 
three-quarters full, stopping and screwing up the 
broken end, ns alito the touch. hole, nnd making a 
constant 6re under it ; within twenty-four hours it 
burst, and mode a great crack, to that having found 
a way to make my vessels so that the| arc strength- 
rned by the force within them, nnd the one to 611 
after the other, have seen the water run like a con- 
stant fountain forty feet high \ oae vessel of water 



rarefied by Are drivcth up forty of cold water ; and 
a man that attends the work, is hut to turn Iwu 
cocks, thot one vessel of water being con^urowJ 
tinother begins to force and rc-fiU with coW water* 
and so Bucccuively. 

*' An engine so contrived, that working the prU 
mttim vinbile forward or backward, opward or dowa- 
ward, circularly or corner-wise, to em^fro, slndght, 
upright, or downright, yet the pretended openCka 
contioueth and advanceth, none of the mocinot 
I above-mentioned hindering, much lesd stoppiDg 
the other ; but unanimously and with harmoiif 
agreeing, they all augment and cuntribute atrcngtli 
unto the intended work and operation ; and, th«tr«> 
fore I call tliia a tfini-omnipoient Engine, and ^ 
intend that a model thereof be buried wiih me. 

*' How to make one pound weight to raiar aa 
hundred as high ns one pound falleth, and ytt tht 
hundred pound descending, doth what nothing !«■ 
than one hundred pounds can effect. 

" Upon so potent a help as these two last. men- 
tioned inventions, a waterwork is, by many vuri* 
experience and labour, so advantsgcou^ly by me 
contrived, that a child's force bringrth op, an hun- 
dred ftfot high, an incredible quuutity of water* 
even two feet diameter, ao naturally, that the woifc 
will not be heard into the nnt room ; and with aa 
great ease and geometrical syminetry, though H 
work day and night from one end of the year to 
the other, it will not require forty ahiUings repan- 
tion to the whole engine, nor hinder one day's 
work ; and I may boldly call it the nutt ^<- -"■••- 
trori' in the world : and not oncly v 
charge to drain all sorts of mines, and fu^^^ 
with water, though never so high seated, as well u 
to keep them sweet, running through aeveral strerts, 
and so performing the work of scavengers, as vtfll 
as furnishing the Lnhsbitanta with sufficient water 
for their privote occasions ; but likewise suppljiog 
rivers with sutticicnt to maintaine and make them 
portable from towne to towne, and for the bettmng 
of lands all the way it runs. With m:iny more ad- 
vantageous and yet greater effects of proflTb, adnd* 
ration, and coniequence ; so that, deservedly, I 
deem this invention to crown my labours, to rrwsrA 
my expenses, and make my thoughts acqniflN ll 
the way of further invtntions." 



STRAW PIAT. 

i Rciuaud fmtn poft 909, am4 tw w cfc l J iM^ I 
Trb chips are whitened, either before or afhr 
manufacture, by steeping them in cold soapy waHVf 
colored with a amall portion of indigo ; after wkliA 
they are eiposcd for some days on the grmas, wbtft 
they are frequently aprinklcxl with clear arater, 
they must not be allowed to become dry. 

Hats manufactured from this material recoi 
themselves by their extreme lightnesa, while 
are sometimes made to assume a delicate end 
ful form ; they are however at best but vory ft 
from their want of flexibility and lirmneas. 

French have endeavoured to i" ■ — • ■ *' '■ 

thing of these qualities by ' 
Bubstnncf!, making h*ita conij 
and whalebone. The warp of this tMiurs u 
formed of whale-bone and trilfov chips, oo« of lbs 
former and two of the latter altcroAlcly. and tM 
woof is entirely composed of willow rJiips. HrtI 
made of this mixture are found moch nmrr da/%l)li 
than those made wholly of wood ybaviugs. 



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MAGAZINE OF SCIENCE. 



311 



f fltniv*, grtnes, and chips into hate, 
t articlcf for wnr, is far from being 
Europe, or to ciriliud countries. The 
found to obtain in differcDt degrees of 
exccllencR in ncnrly cirrj [«rt of the 
^-jM >utliern provinrt-s of China, where, 
|HbopaUtion UM nu other bead cover- 
^^Bc Mandartnn wear these faiita with 
r wide brims, the quauticy of straw 
digtous. In Japan, in proportion to the 
he coniumption is almost eijuslly great. 
■ journey/' says Tbnnberg, •' ail the 
If a conic-^l hut, made of a species of 
and tied with a string." He also ofa- 
ill the fit hrrmen wore hats of the same 

shape. Bat in addition to this ex> 
he Japanese hardly ever wear any shoes 
ut inch as are made of platted straw, 
larks the tame excellfmt traveUer, " is 
bby and indifferent part of their dress. 
loal use with the high and the low. the 

poor. They are made of rirc-straw 

by no means stroue-'* Tliey cost, 
lere trifle ; they are found exposed for 
f town and in erery viUa^, and the 
ippltes himself with new shoes at he 
rhile the more provident man always 
r three pair with him for use, throwing 
I they wear oat. " Old wom-ont shoes 
iption are found lying e»ery where by 

the roads, especially near rivulets, 
en, on changing their shnes, have an 
tthe same time of waihing thrir feet." 
ireather they use wooden clogs, which 
to their straw-platted shoes hy ties alao 
w pUt. People of very high rank 
Mr slippers made of fine slips of rattan 
L 

B of Tonquin wear also broad-brimmed 
id straw or reeds, occasionally platting 

palmeto leaf fur the same purpose, 
enameratfl many other comparatifcly 
lie. we find the wild Indians of both the 
le natives of the South Sea Islands, 
and Hottentots of Africa, and even the 
near the Polar redone, all acquainted 
of platting stripa of wood, graues, nr 
•d wme of them producing, merely by 
» which we, ouisted by all the agency 
r, eould scarcely rival. 
itty and endurable kind of straw plat, 
th America, is familiar to amateurs of 
kbric highly esteemed in all the Spanish 
* aaya a recent traveller. " is that of a 
aas, which is bleached and platted into 
es, such as pouches and cigar-raaes, of 
iarity and fineness. Hats of the same 
: coarser, are ex}>orted in large qnanti- 
nd well adapted to warm climates. I 

veiy little information respecting the 
, farther than that it ^rew on the coast 
vard in great profusion." 



XL CHANGES PRODUCED BY 

MALTING. 
whi«h must strike the most raperficial 
at the structure of the kernel of a 
(•t tn »ppearanci% very different indeed 
* ■ grain of malt. The kernel of raw 
,vy, hard, hurny, and in a alight degree 
^^e kernel of a «eU*mBJled grun is 



light, soft, floury, and perfectly opsque. The eauM 

uf these diirpreuces should properly be sought in 
the analyiris of grain in the two ilifTerent fitates. 

The analysis of barley-meal has been attempted 
by two chetniats, EinhoH' and Proust ; but the re- 
sulta arc so extremely discordant, that there is hot 
little wte in adducing either of them. There it, 
however, a statement made by Proust, which it 
would be improper to neglect. He affirou that barley 
containi a iKculisr pru-timate principle, which, frooi 
the Latin name of the grain, be haa called horHeiru 
Ha describes it as a yellow, woody powder, grsnular 
to the touch, and resembling sawdust in sppear* 
ance. It is insolnble in water, either boiling or 
cold. In the prooeas of malting, this hordein 
disappears io great (juantity, and it is resolved 
chiefly into starch and sugar ; certain quantities of 
which hotl previously existed ready formed iu the 
raw barley. According to Pmnat, the following it 
a comparative estimate of the principles of unmalced 
and malted barley in one hundred parts : — 

Bartfy. MaU. ~" 

Yellow reria 1 part and 1 

tiatn 4 |rftrt»....15 

Su{tu .. fi ........ 19 

Glutaa > 1 

Siarob n 9C 

Uofdclii « &a ...la 

100 100 

The analysis of EinhofT, beside adding albameOf 
volatile matter, and phosphate of Ume to the fore- 
going ingredienta, reproaenta the quantity of starch 
to be more than double what ia stated by Proust ; 
and if to the starch we add the hordein, still tha 
sum will not reconcile the analyses. The proportion 
of sugar corresponds in both estimates sjmoat pre- 
cisely. Bat the most remarkable ciroumataooe la 
the whole ia the total omission of the fixed oil which 
exists in barley, and which has been described bj 
Fonrcroy and Vauquclin aa amounting to a hun- 
dredth part ; and afterwards by Dr. Thomson. This 
oil is of importance : it is of so iiermanent a nature 
as to escape alteration in the processes of Fermenta- 
tion and distillation ; for it is obtained sbundaotlj 
io the dtadUation of whiskey, in shreds. 

In some of its properties this oil rcBcmbles oil o{ 
roses obtained by distillation ; it is concrtto, and 
almost as aoHd u tallow, even in summer : by pe- 
culiar management it may be made to crystallise ia 
blades ; it is somewhat solublo in alcohol, and may b« 
precipitated from its aolutinn by the cfTuaion of water* 
Tliv oil is volnlile, and distils over with water : it 
dissolves oxide of copper, and forma a green com- 
pound : the color of the oil, when newly distilled from 
wash, is variable ; sometimes being pale green, some- 
times white, and sometimes of no decided color: time 
renders it rancid : its natural sracU is not agrreable ; 
it mostly rraemblea distillers* fainU : when dissolved 
in diluted alcohol, it communicates tn it very 
nearly the smell of what, in Ireland, is called p^t*tn 
whiakey ; and good jndgea were deceived by it. 
What is called the whiskey smeii of spirit is owing 
to a small qaanlity of tlits ml held in solution. It 
is not so volatile as alcohol : hence frequent rectU 
f^cations of common spirit afTord a product having 
letsand less peculiar smell : hence, in the diMiller'ft 
prooMa, the singling! contain much oil, becnc 
they were distilled at a high temperature, on aecoant] 
of the great quantity of water present: hetuse, tb«;| 
■pint prodoccd first in the rectification of sincUn| 
is much freer from oil than the latter portiontfj 
when the temperature riaea ; and hence the very 



312 



MAGAZINE OF SCIENCE. 



but prodncU from the singlinss have so diugFecJible 
an odour, t)ccan»« then the oil romn over abun- 
ilnnLly. The points of resembluioe between this 
oil utid oil of rusci arc their loUtlity, thetr volatility, 
their Icaring & gr^sy fttain on paper, which requirej 
a ttnmg heat to expel, their tendency to rancidity, 
their cry stall isubility, and the uncertainty of color. 
The properties just explained place tliese two oils 
OS the link of couneclion between what are called 
filed ami volatile oili. 

Dr. Thomson is of opinion that the hordein should 
not bo considered s peculiar proximnte principle ; 
and that it is merely ftnrch in a pnrticuUr state, 
somewhat similar to the fibrous matter of potatoes. 
Maltiog converts it partly into sufjar, and partly 
into common starch, by destroying a certain un- 
known glutinous substance, which glues the particles 
of it so firmly together. Yet the presence of sub- 
stance In barlcy-roeoi in so great a quantity as more 
than one half of the whole weight ; its being woody, 
and Insoluble in water whether cold or boiling ; its 
disappearing during the mslting; and the increase of 
the gum, sugar, and starch, in consequence; are 
properties not attributable to any component psrt of 
any grain «-ith which chemists have hitherto been 
acquHinted. Hence, in strictness, we are bound to 
admit hordein us a peculiar substance. 

As to the original question just proposed, and 
wliich brought the invcstiffation of Proust under 
consitlcration, it still remains to be answered, what 
is the cause of the diflference of their mechaniail 
structure ? And although the analyses of EinhofT 
and Proust differ so materially, yet chemists agree 
that raw barley, amongst its other ingredients, con- 
tains gluten, gum, and sugar; and there ia oven 
tolerable accordance in the quantities assigned. 
One hundred parts of barley-meal contain about 3^ 
partA of glulrji. if of gum, and 5f of sugar. Now 
these are all of a glutinous nature, calculated to 
bind the starch and the other ingredieota into a 
solid mass of great hardness, such as we know a 
barley-corn to be. For such is the hardness of 
gluten, that it hss been used to join fragments of 
pottery. The following is a fact illuslrative of this 
Htatrnicnl : — If barley* reduced to the finest powder 
and the husk removed, be made into a paste with 
water, rolled into grains resembling the original 
barley, and exceedingly well dried before a brisk 
fire, but not scorched, they become almost as hard 
u the natural gnun. But this powerful cohesion 
has taken place between particles which had been 
already diaintegrated, and removed from each other. 
How much more powerful mukt be the cohesion of 
particles bound together by gluey matter, which had 
grown along with the ingredients of the com. which 
cemented — not parttclcD formed by the artificial 
process of grinding — but the ultimate particles of 
which that kind of matter is composed. In such a 
case, it is not wonderful that particles so much more 
closely approiimated, and so much mure intimately 
penetrated by the cement, of which two of the in- 
gredients are perfectly transparent, and the third a 
good deal so, should be so affected as to be at least 
I homy, if not in a slight degree transparent, as we 

M find a ripe dry harley-com to be. 

I But when barley is steeped in water, with a riew 

I of malting, the cement is softened, the particles 

■ now cohering with but Little force, are acparatird to 

I a greater distance from each other, so that the 

I ^tedfie gravity is leaseoed by the absorptioa of 




water and oooseqaent swsUing of tho gnnn, aod 
perhaps by the evolution of the oarboaifl acid* 

liuring the progrrss of j^ermination, tbs qtuotilf 
of the chief cement, the gluten, is leaseiml frooi 
tlirt^e (jsrts to nnn. by chemical changea in it ; anil, 
in fthort, the whole constitutian ii suhrertcd. 

It is a matter of opinion, admitti-d by soma ind 
denied by others, that the change efTfrtcd in b*rU| 
by malting is complete ; that it affects vrcry in* 
gredient of the grain ; and that the whole aab^anee 
IB converted into new matter, which did DOC pnvl- 
ouily exiit in the grain. What tba natorr erf tin 
new matter may be is not yet agreed oa. T>irvr uf 
two opinions. It is found that hot mter : 
of dissolving away every Uiing from Bul 
the husk. This, it may be supposed, • 
happen unless there was a total change ' 
the starch and gluten of the barley. St 
true, is soluble in boiling water ; the rf 
ever, is not a solution, but a weU-knon 
wiiich becomes even more stitf by cooling, 
solution obtained from malt ia perfectly 
ther hot or cold. From the disappe 
starch, and the obrious formation of sn 
been supposed that the result and ol 
are the total conversion of the stan 

But a dilferent view may be taitrn. 
supposed that, during the nalUiig pr > 

change of starch into saccharine matter i& ^ - 

tial i that the malt still contains much tinaltrrrJ 
starch: and that, by the action of hot wivti-r, !»' 
conversion into aaccharioe matter is lu 
pletod. In short, it has been conceived, 
much probability, that the sugar-foriuing procest <• 
resumed and coulinued during the action of tike IujC 
water. 

GALVANIC PLANT PROTECTOB. 

Mu. Cl'tubbrt, of Clayton-squaro, LiTonOoV^ 
successfully applied the galvanic prindpu M llv 
preserration of planta, from the attails of shio or 
worma. This inTention, which prr(i:i:liy •snres 
dahlias and other delicate plants from the 
those voracious pesis of the flower garden, 
lusra, must be highly acceptable to all 
tlieir culture. After a trial of twelre months 
inventor, not a plant was Injured that had 
tection of these golTanic circles, although 
same period plants on oU sides suffered 
were not so protected. The protector oonai 
conical ring of tine about four inches in hei) 
top end flanked off about a quarter of ao io( 
cut into numerous vandykrd points; tmml 
under is a ring of copper neatly fitted. It 
used : — Tlie bottom of the sine ring is pr« 
the mil until the lower edge of the copper 
about one inch and a half above the sur^ce 
being taken to inclose within the ring 
such plants as may require them, otbi 
molluica find a road to the plant by the 
moUusca may cravl into tlie sine witli im| 
but, on coming in contact with the copper*' 
receive a galvanic fhock, and immedintely turn 
or fall to the ^ound. If the large?! of this 
attempt to stretch serosa and above the copprr bflt. 
avoiding contact, they would be incapable o( hold- 
ing by the points. The protector acta in wci orixj 
weather, ood is always in action. Its api»ear«M»w 
use is like a flower-[>ot ; and ita chrapnm, 
and darabitity, must insure ita general adoptii 

LoiriKiv.— 4*nDl«d hj D. roAwci*. C, Whtia Hon* Lao«. Mtla Kad— PoMlkhtd by w. BatrtAP), 1 1 . Patoroofivr 
fidlnbutigh, J. MSmisa.— 421aMgow, D. Baica and J. BAaaaa.— Llvitpool, G. Pauir. 



THE 



MAGAZINE OF SCIENCE 

gtnli Scjbool of ^rtjs. 



BATUAOAY, JAMUARY I. l&OL 



[Ud. 




ECLIPSES AND SK)TiS UPON THE MOON 



To ohsfTve ail eclipM* of the moon, in such b niaonfr 
U Cu bfi uiriul to geography and afttronomf, it will 



Y, in Uio first place, to have a clock or 
L tbat uidieatnt seoondu, and whii-ii joa arc 
n i» to well coiutructed ai to go in an uniform 
«r : it oa((ht tu be re^alated wme days before 
a of n meridian, if you have one traced out, 
me of the methods employed for tliaC par- 
by aatrunouieri ; and you must aseertttia lio«r 
h it %ocA f&st or «low in twenty-four hunri, 
tkiak the difference may be taken into account at the 
time uf the ohanvntion. 

You nuxht Co be provided alao with a refracting 

!><!, Bom» feet in ienelh ; for 

mnrc crrtaiu you mil he of 

._* ...c momftit of ibe phit^es uf the 

' you are dcsirnua a( ohirr^ing the 

- cch|ifc. it should be fumiihed with 

mu:ruiiicCcr. 



' M'hen you find the moment of the eclipse ap- 
pronrhtng. which may be always known cither by a 
common almanac, or the Ephemendea published by 
the nstrononierA in difficrent parts of Europe, you 
must carefully remork the inatjint when the shadow 
of the earth touchcH Uie moon's difc. It is necessary 
here to mention, thnt there will always be some on- 
cerlsinty on account of the pcuuoibra; because it 
it not a thick black shadow Mhich first covers the 
mcMo's disc, but an imperfect one that tbiekeiiR by 
degrees. 'lliie» arises from the snn'a disc Ijcing 
gradually occulted from thr moon ; and henc« it u 
difficult to fix with uActnrss tlie real limits of tho 
shadoWf and the penumbra. lit^ru, as in many 
other cases, observers arc enabled by bahit to lUs- 
tineutsb thift boundary : or at least preTontcd from 
falHne into .hit Rrcjit error. 

When you are certain that the real sh«dow has 
toacbed tlie moon's diac, the lime must be ootad 



314 



MAGAZINE OF SCIENCE. 



down ; thit it to saj, the hour, mioutr, and Kcond, 
Bl which it happened. 

lo tbi» manner you most follow the tbadow on 
the moon's disc, and remark at what hour, mtnuti;, 
Uld seouod the sbadan reaches the most remarkable 
tpota : all this likewise must be noted down. 

If the eclipse is not toiAl, the shadow, after haTlng 
COTcrtd pirt of the lunar disc, will decrease. You 
must therefore obserre iu like manner the moment 
when the shndow Icarea the different spota it before 
covered, ond the time when the disc of the moon 
ceasea to be touched by the shadow, which will be 
the end of the eclipse. 

If the eclipse is total, so that the moon's disc 
mnoins wme time in the shadow, you most note 
down the time when it is totally eclipsed, as well as 
that when it begins to be illuminated, and the 
nsommu when the shadow leavea the different 
•pota. 

When this is done, if the time of the commrnre- 
jnent of the eclipse be subtracted from that of the 
end, the remainder will be its duration ; oiid if half 
the daration be added to the time of commencement, 
tlie result will be the middle. 

To facilitate these operations, astronomers hare 
giten certain names to most of the spots with which 
the mooo*s disc is covered. 

The usual deiiominxtians ore those of I^angrenus, 
who distlngnished the greater part of them by the 
nnmcs of astronomers and philosophcri who were 
his contemporaries, or who had flourished before 
his time. Some others have been since added; but 
there was no room for the most celebrated of the 
modems, such as Huygcns, Descartes, Ne wton, and 
Cassini. HeTcliuSifar more judicious in our opinion, 
gave to these spots names taken from the moft re* 
morkabte places of the earth : in this manner he 
colls the highest mountain of the moon, Mount 
Sino). Stc. This however u a matter of iDdiHerenne, 
provided there be no ix)ofuston. We have here 
subjoined a represcntatiou of the moon, by means 
of which and the following catalogue they can be 
easily known, on comparing the numbers in the 
Utter with those in the former-. — 



1. Grimaldi 


23. 


AriRlotle 


2. GaUileo 


24. 


Maniliua 


3. Aristarchaa 


25. 


Mcncliius 


4. Kepler 


2G. 


Hermes 


5. GosseniU 


27. 


Posidonius 


6. Stdiikard 


28. 


Dionysius 


7. Uarpalua 


29. 


Pliny 


B. HeracUdes 


30. 


Catharina, Cyril- 


9. Laoftfaerg 




lus,Theopilaa 


10. Rhciuhold 


31. 


Procastorias 


1 1 . Copernicus 


32. 


The Acute Pro- 


12. Helicou 




moutory 


13. Capuanua 


33. 


Mrssala 


14. Bullialdi 


34. 


Promontory of 


15. Eratosthenea 




Dreams 


IG. Timocharia 


35. 


Proclua 


17. Plato 


3C. 


Cleomedcs 


19. Archimedes 


37. 


SncUiua and^Fftr- 


ig. Ule of the Middle Bay 




nerius 


20. Pittacus 


33. 


Peuu 


21. Tycho 


39. 


Laiigreuua 


22. Euduxus 


40. 


Toruntiua. 


A 8ea of bnmovni 


E Sea of tranqniUty 


B Sea of clouds 


F 


iea of »ecunty 


C Set of rolu 


G 


Sea of fecundicr 


D Sea of nectar 


U Sea of criset. 



lint 



TIME TOLD BY A SHILLING. 

Wb insert the following paper from the A'aiMMf 
AdvertimtT, because we have been repeatedly Mk«4 
for au eiplanatioo of the phenomeuon, and to iu(- 
lect it, would be to treat very numerous corre** 
pondenta with neglect ; at the same time, we do Bot 
take for our own the sarmisea contained in t&t 
following, on the contrary, believe that there ia fto 
truth whatever in the eiperiment, and that ths 
success of it depends entirely upon our knowing, 
or. at least. gueMlog, beforehand the actual tlms; 
and that we may make it succeed <■' ■"•' ^t on/ 
pleasure. Expenmcnts ujion the sul ton 

prerionaly acquainted with the vtUh- mk is 

not a fair test ; let a stranger, or a cUUd who never 
has heard of the eiperimcnt, or a person whe* joit 
awake try it. the light being such that I 
guess at the time of dny, atid If it then aii< 
than once, we will admit that there ia aoioeimnf 
to argue upon, but not otherwise. 

*' However improbable the followi-- ---r-;^ — -* 
may appear, it has been proved bv 
— Sting a shilling or sixpence at liu' 
of thread by means of a loop. Then rce 
elbow on o table, hold the other end of >i" 
betwixt ironr forc-fingcr and thumb* obsetttii^u 
let it pasa across the ball of the thnmb, and 
suspend the shilling into sn empty goblrt. O 
year hund mun be perfectly steady; and if 
it difficult to keep it m an immoveable pi 
useless to attempt the experiment. 
however, that the shilling Is pro{)erly 
you will observe, that when it has recovered 
e(]uilibrium, it will for a moment be stationary; 
will then of it« own accord, and without tJie Iet»t 
agency from the person holding it, assume theocCioo 
of a pendulum, vibrating from side to fi 7 ' " 
glua ; and, after a few seconds, will sCrili; 
nearest to the time of day : for instauu.. 
time be twenty-fire minute-s past cix, it will 
six; if thirty-fire minutes |>ast six. it wUI 
seven ; and so on of any other hour. It is 
aary to observe, that the thread should lay over 
pulse of the thumb, and this may in some 
account fur the vibratirm of the shilling ; but 
cause Its striking the precise hoar is lo 
remains unexpUuoed ; for it is no less 
than true, that when it liaa struck the pro 
ber, its vibration ceases, it acquires a kin! 
motiaD, and at lost becomes stationary, aa bi 

(T(i tht mUor (\S th€ SiUwnat JJftrtitef.J 
Sin. — Having read in your highly Taltnble ft0t 
the above notice, I tried a series of experisseaUt 
and thejaci of the hour being " told by a suspeodfl 
shilling," 1 have proved, I thmk, for every hoar ia 
the day ; but 1 honeatly confess 1 cannot e-xplam 
but perhaps this may meet the eye of 
may be able to do bo* and I tlierefore give my 
trials, hoping thereby that the true caiue 
elicited. Animal magnetinui is beyond mr, 
nervous infiuenee was explained to mc by "Ojlsr," 
OS being electrical, and I have never h&d raaaoto 
doubt it. That electricity or magnetism doei frrrf 
its power without contoct, we all icntjw; ^■■■ 
galvanometer, causing the deflection of thr 
needle. As I cannot prove that it <■ tl 
shall leave the matter in other hands, mrr< 
that a friend uf mine explained it *>" 
the mitul which produced the etfect 
ma vgftiik ; but I will give my c:t; 



ncoa^ 



but 



J 



MAGAZINE OF SCIENCE, 



•hall b« lupp7 to learn, Uurou)th your colDmnit, that 
other* hiTC prared ttw rorrectnett of dit triiile. 

Iron, ciT^iprr, bnaa, silver, and nold, all prmluced 
Um vlTmrt wbfD impended. Gbuu will not auC when 
IBfpfTidfd. 

The old |>cnn]r acta very well, but the ibillinR 
httccr ; but the ronrprnny-piece I preferred. I 
fcaeird that the fibnttion took place brlter in a dry 
wni cluf. 

1. Ruromrr, or goblet (the beat fonn) bIwbji 

■5 ]■»■. 4 1 incbei diameter, aniwereil Tcry 
dry. would not when water waa poured 

Wbwi th« ooin wis tuspended bj ailk iDitead 

i» I oould not miike it act. 
UalcM the elbow rest on the Ubie, no effect 
whm rrsting on the table it answers aa well 
thr left ■» with the riKbt Arm. 
rasa mp. 4 Inclica in diameter. The tns- 
piece vibrated bat never touched the aidea, 
•oon at reat. 
0*ia receiver, with braaa cap and stop-cock — 
irwl the stDp.CDck (by which the bottom was 
•pcB). placed it to stjind with th<* brnM end on the 
lalilf - Tibmtion as in No. 5, but nothing more. 
; <: ...i.-f .. ,ti, fourpennr -piece at the bottom; 

fc ' ■ nine o'clock, with snspended shil- 

iiaf unick the nnmber nine — wif again tried, 
•^rt whilft in the act of atrikinp tlie glaaa («nd 
' id done five times), a person clipped in a 
piece, it struck no noore, and the vibra< 
won rci-urd in a abort time. Anoth«'r rnae at ten 
[•^•lock, as aoon as it had touched the glass twice, 
■killinS waa thrown into the goblet. It struck no 

4. Larcc tamp ginsa, with a cork bottom (which 
vmld h'lld water), this woutd not act. 
in Wet ^aH, like No. 9. 

lU and iron balls. I did not succeed ao 

iheae. the iron bill struck the nnmber, 

•1 .!.>- orosa ball went on until it struck 25. and 

jVOald hiTT continued, but I altered my position. 

I H'Tf/ licarj the abilling strike more than 12. 

■ M hot a few remarka to the above. 1 
uu many occnsions, tliat abould the sua- 
fioin fail of striking all the hours rnnsc- 
r, it will vibrate on until it obtains auflficient 
to perform its work. In ittriking 12, it 
glaaa seven times, then turned round 
'"-■T^ for M-Tcral seconda ; but at Uat 
'tilom-like motion, and touched the 
iiore. I have seen thia with othera 
It,- the nnmbera were aot aevea and fire, 

!«>p«rator muat hare a steady hand and arm, 
fiiir proportion of patience. 

Ill My, I met a gentleman who told me he 
e«MJd do it, and another informed nie he 

that i glaas vessel open at bnrtom will 
, neither a wet one, nor when water is in it, 
■or when a motal cup is naed, nor when 
ynriwhiii^ ia not of metal, nor the string of silk, 
dMt ita b«st effect is produced when the glaaa 
•am. I hope these trials of mine may be proved 
fwct by ether*, and abler handa ; and sbould 
r be ao, we may then say they took like electrical 
iBO. rodsht waltsb Bvaaa, r.L.a. 

mvOmwirrM, Abvi IS. IMI. 



PUtM 

irthlfl 



latM 



EFFECT OF HEAT ITPON CJIYST.VLS. 

Thr very ruriona subject of the influence of 
upon double refraction hat been recently ioi 
gated by Professor Mitacberlich, of Berlin ; but 
regret that it ii out of our power to give anythl 
more than a meagre accouot of some of hia rnsalCt. 
In uncryAtallisfd bodies, and in all crystaU which 
have no double refraction, a riae of temperatura 
tlirougbout the whole moss producea an equal ex- 
panrinn in all directions, without any change of 
figure. With doubly refracting crystals the case is 
different. When calcareous spar ia heated, it dilat 
in the direction of ita aiui of double refractit 
but Professor Mitacherlich found that in all oi 
directtona at right angles to this axis it contracts, 
ao that there must be a line inclined to the axis in 
which there is neither dilation nnr contraction. 
Hence the angles of the crystal are changed by beat, 
being diminisbetJ (by a heat from the freezing to the 
boiling points 8' 30" in the dihedral angle at Che 
extremitiea of the axia. Ita form being thiia brought 
nearer to that of the cube, which has do double re- 
fraction, its double refraction, aa might have been 
expected, ia diminished. M. Freanel found that 
beat dilates sulphate of lime less in the direction of 
ita priucipat axin uf double refraction (in the plane 
of the lamina;) than in a direction perpendicular to 
it, a difference analogous to that of calcareous spar, 
but of a contrary character, aa might have been 
anticipated from the opposite nature of the refraction 
of these two minerals. 

- These results being obtained by very nice experi- 
mcnts. which but few persons are able to repeal. 
Mr. Herschel has given the following ex^wriment aa 
an ocular demonstration of the truth of the general 
fact of unequal change of dimension by cliange of 
temperature ;— *' Let a imall quantity of tlie »ul' 
phate t^f potnMh and copper (an anhydrous salt 
easily formed by crystallising together the sulphatea 
of potash and of copper) be melted ia a spoon ovo^H 
A spirit lamp. The ftision takes place at a beat jii||^| 
below rednrss, and produces a liquid of a dark green 
color. The heat being withdrawn, it fixea into a 
Bolid of a brilliant emerald green color, and remains 
aolid and coherent till the temperature sinks neariy 
to that of boiling water, when all at once ita cobe- 
sion ii destroyed ; a commotion takes place through- 
out the whole mass, beginning from the surface, 
each molecnie, as if oaimated, atarting up and 
separating itself ffom the rest, till in s few moments 
the whole is resolved into a heap of incolierent 
powder, a reanlt which could evidently not tuke 
placrc had all the minute and interlaced crystals, of 
which the congealed salt consisted, contracted equally 
in all directions by the cooling proceaa, as in that 
cane their juxtaposition would not be disturbed.'* 

When Professor Mitscherhch was examining the 
doable refraction of the hydrona sulphate of tnaff^^m 
nesin when bcnted in oil, he ubsen-rd thnl it xiif^H 
fered no change till the tcmpernture reached i'itr^ 
of Fahrenheit. The crystal then became opaque, 
and on being broken, it showed the structure of a 
pseu^o-morphouB crystal, consisting of a number 
of individual crystals, beginning ht the surfsce and 
meeting in the inride of thr original crystal. The 
same effect was produced nt the tame temperature 
on the hydrous tulphaie of zinc • hence he infere 
that a movement of the particlrs of a solid body 
may take place, by which the particles uke ■ ne«r 
symmetrical arrangrmeut, and form a new miner 
species. 



nineral^l 



3IC 



MAGAZINE OF SCIENCE. 



'I'h*! most Litraurdinnry fact, however, tlUcovered 
by Proft'iftor MiL:>ulicrlit:li relitcs to ilie influence of 
liriit ou the duable rcifracitou of gittphate of Inrve. 
In thin miner*], whirh hai two rrsultunt avps in the 
pUne of tlie UuiiuK inchiivd it(f, ilieio two aiei 
|;raduall)i a{tproiii^h with bent uU tbtry unite, and, 
when further beAt«d, they again o]»eD out on each aide. 

NEW DISCOVERY IN PRINTING. 

Thk progrcM of dJAcoverf is »o rapid, that tcaroely 
a week piuse*, in whirh wc nrr not nttlrd nn to an- 
iiuuDce Butne of its wonder-working tnirttrltft. Early 
in October, we received, from a corr««pondent at 
lierlio.a re-print of the fourpsgcaof the/IMrad-um, 
(published iti London uiily on the 25th of Sfpteoj- 
ber,) which contained the review, and itt ilJuiiratiom 
of "The Porcelain Tower;" how produced, our 
correspondent could not inform tu — but obTioutly 
nat by uny known process. The copy was so [>tT- 
fect a fRC-simile, thut had it reached lu under other 
ciroamttancrt, we xliould never have tuftprctcd that 
it had not beeo iisued from our own othce — and 
CTeu when our mttcnlion wu thus specially directed 
to Lbc subject, the only ditfcrence we could di«- 
COTcr was, thiit the imprcuion was ligbter, and that 
there waa leas budy io the ink ; from which we in- 
fer that the procesa is estentioJly lithograpbtc, the 
impreision of the original page being, in the first 
inatuitce, transferred by some weans on to the sar- 
fttce of the stone or xinc plate. Tliis, however, ia 
hut a conjecture, and our correspondent is unable 
to throw light on the subject. In reply to oar 
urgent request for further informatjou» he thiu 
wriCea : — 

•' BerUn. ^'or 85. 

" I have not ceased to exert myself to obtain the 
information yoQde»ire, but all I can collect ia briefly 
this. The process by which these fac-simllr re-prints 
are pruducei), was discovered by a genileman at 
Krfurt.nnd is kept a profound secret. I have since 
seen a copy of an Ambic MS. of the thirteenth cen- 
tury, and of a leaf of a book printed iu 14B3, both 
of which have been produced without the slightest 
injury to the origintli, so that yoar Bibliomantaci 
roAy despair of ever again seeing an unique copy. 
I'he parties in possession of the secret are shout to 
rr-publiah here the At Aeiu^um, and are to commence 
rtprruUnns with tbe first number of the coming year. 
1 have seen the draft of the proipectus. io wbich 
thry offer to supply the trade at the rtite of three 
tlialera (nine shillingH) per annum. They will be 
rnnient too, I understand, with three hundred sab- 
scriliers, and from this fact, you may form a con- 
jecture as to the probable cost of the proceu. which 
must be below what the tnerv paper costs you," 

Now, so far as our pecuniary irkterests are con- 
cerned, the ijurstion is not worth a second thought. 
The snle of the London edition of the AtAentevm 
in Germany is necessarily limited by the enormous 
postage charges to the principal libraries, the 
literary and scientific societicv, and Kume few wealthy 
individuals resident in the prtm^ipal cities. 

Uut to book-publishers, more especially to the 
publishers of coHtly works, illustrated with wood- 
cuts, it is one of vital importance. THke. for ex- 
ample, the admirable series of works on Nnturul 
Hiat«>ry, bjr Varrell, Bell, and others, published by 
Mr. Van Voorst. There can be no f|iiest.ion that such 
works hqve had a very extensive sale all over the 
QiViliaed world, for the cofiyrit;lit has been secured 
to lite publibhcr by the enormous cost of r«< 



producing the numberless bcoatifiil lUiumbORS— 
but here ia ■ proorss by which the forvigncr rm n ■ 
produce the work, illustrations and all. »'■ 
thecoal of paper and press-work ; and of > 
roanofactoriea will be forthwith e^tablislitrd.Nudouf 
market, even in our colonica, inundMlrd nitti ttr«« 
spurious ediitous, Inpt< 
conjectural or puMible ' 

that our correspondent i... 

pamtious are already made tu pi 
Shaketprre, nhich is snnouuced ^ - 
at siX'pennea number. Surely, govcrnruent, uufl«r 
these circumstances, will now bestir itself, and toks 
active meaAUrcs for the estflblifthment tif e*tmt 
international law for the prutcctiua of tif hon>vt 
men of oU natiuus— and all nations are etju^llv con* 
cerned. This, however, ift a antijc>ct ino taikt lu da 
entered on in ft paragraph — and, inV..! il-. 
necessary, as wp have so oflco cxprr-- 
We have tberrfore, only to add, th-n, 
faction of those who are ao deeply ii»i«rt«t«d| 
ahull forward the copies received from Bet 
our officw. in Wellington Street, where they 
be eihibiled and compared with the viigUiab.— 



PHOSPHORUS. 

1. This iabstanoe was discovered by Bl 
1669. Iu specific gravity is 1-77. 

2. Pure pbospbonifl ia nearly cotorlei 
transpai-cnt, wnd flexible. It melts, air ' 
eluded, at 105'^. Kxpowd to Ibo air. 
luminous fames, having a peculiar lUiaccitu ^ — 
It is ttmteless, insoluble iu water, and proves poiawoMi 
when taken into the stomach. 

3. It is found in the bones and urine of eu* 
nivorous animala ; wavellte, (phosphate of aJomias,) 
apatite, (photiphate of lime,) bog iron ore ; loM 
other ores of iron, &c. 

4. Heat bones in an open fire ; a whi^r — "-^ 
remaina, compnsMl principally of pho»[ i 

and lime : by sulphuric acid, the greater 

the lime may be removed; and if the - 

heated with charcoal, it removes the oi ; 

the photphoma is converted into vapoor. Dcginoctt 

should not attempt such a complicated prooesa. 

5. Put a little pbosphoms, previoualy dnedon 
blotting paper, into a deflagrating ladle ; inflam* IU 
and put it into a dry jar of otygeo. Il unites witk 
the uxygeu, and thus produces phosphoric wOdt 
which falls down like flakes of snow. 

6. Put a few grains of phosphorus into a |Imi Jl^ 
and cover it with boiling water; force oiyg««g*»<*i*' 
of a bladder upon it. The phoapbnrua b* i ^ 

to the beat necessary for taking fin, onU 

the admission of the oxygen, and imuicuiaUJT >'•• 

flamea. 

7. Place a thin slice of dried ph"«v''*"""" i^*"!* 
a quarter of a grain,) between a i«\y 

paper ; rub this nith a glass rod, av. 

duced by the friction soou intUmea tlte pUoaj 

H. Hutd a stick of phosphorus by a 
pincers, and draw lines with it upon a board 
dark room ; wherever the phosphorus toucl 
wo<^id, a ]>ortion is absorbed, wluch rvtaioi' 
luminousness for some time. 

9. Into a very smalt retort pttt a few grain* oT 
phosjihorus, and cover It with a sototiun of c»mO* 
potsfsa ; apply heat by means (tf a spirit Unp' 
After a httle time, a gas, called pbospbarewd 
hydrogen, which inflames as soon aa it cooes n 



MAGAZINE OF SCIENCE. 



319 



, and tint the talento which it requires 
e*n« of Ihc highest order. It is fliill 
tant that they should be impressed with 
on tiut the greftt merit, sod the great 
bote wbo have nttunrd to eminence in 
to, wu tlmost entirely due to tho un* 
«e«ersnce with which they concentr»led 
mcceMfnl iDTeoCions the ikill and lcnow> 
ymn of study hid matured. 



TOBACCO. 

lut the name tobacco waa given by the 

the plant, becaose it was first ubserred 
hbuco, or Tabaco. a province of Yucatan 

In 1560, Nicot, the French ambassndor 

> having received some tobacco from a 

Mt^ant, ihowcJ it, nn his arrirol in 

the grand prior, and, on hia return into 

Catherine of Medicis, whence it haa been 

itJaoBk by the butaniata. Admiral Sir 

Kka having, on hia way home from the 

iin, in l&8t>, toucheil at Virginin. and 

y some forlorn colouistR, is reported to 

tmpinted tobacco into England. But, 

|o I^bcl, this plant waa cultivated in 

pre the year 1570; and wan consumed 

|| in pipes by ^sir Walter Raleigh, and 

k «o early oa the ^car 1684. 

'M are hung up to dry during four or 

taken down out of thts slK-ds in damp 

in dry they would be apt to crumble 

Btratilied in heaps* covered up, and left 
a week or two, according; to their quality 

of tbe aeoson ; during which time they 
freijuently, opened up, and turned 
nr bonme too hot, take fire, or run into 
innaentation. Tliia procese needs to be 
fy skilful and attentive operatives. An 

negro can form a sutlictently accurate 
r the temperature, by thrusting hia hand 
the heap. 

BOO thai prepared, or often without fer- 
b MDt into the market ; but, before 

miiBt undergo tbe inipertion of officers, 
by the state with very liberal salaries, 
liiie its quality, and brand an appropriate 

its casks, if it be sound ; but if it be 
imed. 

crtmble tobacconists are very careful to 

the damaged leaves, before they pro- 
ir prrpnration, which thry do by spread- 
a heap upon a utoae pavement, watering 
a nieoeesion, witli a solution of sea bait, 
iravity l']07. called sauct, till a ton or 
i ; and leaving their pnntnplea to re- act 
Iter for three or four days, according to 
kture and the nuture of the tohncco. It 
rohable tiut ammoniii u the volatilizine 
Mny odours, and efipeeially of ihoM of 
t musk. If H frrsh grren leaf uf tobacco 

between the fingers, it emits merely the 
smell common to many plants ; but if it 
d in a mortar, aloiig with a li||le qnick> 
KiepoCaah, it will immediately exhale the 
our of 8nu6*. Now analysis sbnwi the 

muriate of ammonia ui Uii« plnnt, and 
n serves f\irtber to [jenerate free ;iitimottii^ 
ce, by means uf Uiis prmr**, and Umy, 
vehicle is abundantly di^vojuped. If, 
tbe excess of sJkalinr mutter in 
afaofs be saturated by a mild dry 




acid, as the tartaric, its peculiar aroma will entirely 
disappear. 

Tobacco Rootains a great quantity of an oaotixed 
principle, which by fcrmeutatiou produces abundance 
of ammonia ; the first portions of which <taturate the 
acid juices of the plant, and the rest serve to volati' 
lize its odorous principles. The salt water is useful 
chiefly in moderating the fermentation, and prevent* 
ing it from passing into the putrefactive stage ; 
just as salt is sometimes added to saccharine worts 
in tropical countries, to temper the fermentstivc 
action. Tbe sea salt, or concentrated sea wster* 
which contains some mariate of lime, tends to keep 
the tobacco moist, and is therefore preferable to 
pure chloride of sodium for this purpose. Some 
tobacconists mui molasses with the salt sauee, and 
ascribe to this addition the violet color of the 
maroMbn snuff of Martinique ; and othf^rs ndd a so- 
lution of extract of liquorice. The following pre- 
scription is that used by a skilful uonafocturer : — 
In a solution of the liquorice juice, a few figs are to 
be boiled for a couple of hours ; to Che deowtion, 
wbUe hot, a few bruised anise-seeds ore to be added, 
Add when cold, common salt to saturation. A littlo 
spirit of wine being poured in, tbe mixture is to be 
equalhy, but spariiigty, sprinkled with the rose of a 
watering-pot, over the leaves of the tobacco, as they 
are successively stratified upon the preparstiDn floor. 

The fermented leaves, being next stripped of thrir 
middle ribs by the hands of children, are sorted 
anew, and tlie large one-s are set apart for making 
cigars. Most of the tobsccos on sole in our shofta 
are mixturej of ditferent growtiis: one kind of 
smoking tobooco, for example, consists of 70 psrta 
of Maryland, and 30 of meagre Virginia; and one 
kind of snuff consists of 80 parts of Virginia, and 
30 parts of either Humesfort or Warwick, The 
Maryland is a very light tobacco, in thin yellow 
leaves \ that of Virginia is in large brown leaves* 
nnrtuous or somewhat gluey on the surface, having 
a smell somewhat like the figs of Malaga \ that of 
liavanuah is in brownish, light leaves, of an Bj^recoble 
and rather spicy smell ; it forms the best cigars. 
The C'arolina tobacco is less unctuous than tbe 
Virginian ; but in the United States it ranks next 
to tlie Maryland. The shag tobacco is dried to the 
proper point upon sheets of copper. Tobacco is 
cut into what is colled shag tohoeco by koiCe-cdged 
chopping stamps. 

Mr.L.W.Wrigl^obLainedapatentinAugnst, 1927| 
for a tobacco-cutting machine, which beora a close 
resemblance to the well-known machines with re- 
vulviug knives, for cutbng straw into chaff. Tbe 
tobacco, after being squeezed into cakeA, \& placed 
upon a smooth bed wiihin a borixontal trough, and 
pressed by a follower and screws to keep it com- 
pact. These cakes are progressively advanced upon 
the bed, or fed in, to meet the revolving bludes. 
The speed of the feeding. serew determines the degree 
of fineness of the sections or panicles into which 
the tobacco is cut. 

\}t, lire was employed some years ago by the 
Excise, to analyse a quantity of snafT, seized on 
suspicion of hnririg been nduiterated t>y the manu- 
facturer, lie found it to be largely drugged with 
pearl-ashes, and to be thereby rendered very pun- 
gent, anil absorbent of moisture ; an economical 
method of rendering an uficte article at the sune 
lime active and aqueous. 

According to the r^'cent analysis of Possrtt and 
Reimann. 10.000 piirts of tohncco 'leaves contain 
6 uf tbe peculiar chemical principle nicotint i 1 of 



920 



MAGAZINE OF SCIENCE. 



nicolianine ; 'J87 ofiLiThUy bittercxtrurtiTe; 174 of 
gum, iDiinl with a little malic Mrid ; 2ti'7 of a ^rccn 
ndn; 26 of vegetable ftlbuoien ; 1048 of a tub. 
tfanofl anoloirous Co gluten ; 51 of malic ncid ; l2of 
laklate of auimntiiv ; 4*8 uf milphale tif poUiM ; 
6'3 of chloride of potusiuin ; 9*5 of potanu, which 
l»d been oombinptl with malic and nitric acids ; 
16'6 of phoHplult(^ of lime ; '14'2 of lime^, which had 
been combiued with malic acid ; 8*8 of silica ; 
496-9 of fibrous or ligneous matter; traces of starch; 
•nd 88-28 of water. 

Nicotine is a trtmspurfnt colorleaa liquid, of an 
iklkttUne nature. It muj he distilled in a retort 
plunged into a bath heated Co 290" Fahrenheit. It 
Yuu m prickiiur, burning taste, which is vtrry durable ; 
■nd a pungent diiuifp-ernble tmell. It bums by 
meaoa of ■ wick, with the diffusion of a vivid light, 
■od madi smoke. It may be mired with water in 
■11 )iroportioaa. It ia mluble also in acetic ncid. 
oil of almoada, alcohol, and ether, but not in oil of 
tuqietitine. It acta upon the animal economy with 
extreme violence ; and in the done of one drop it 
killa a dog. It forms salts with the acids. About 
1 part of it may be obtained by very akilfol treat. 
ment from 1000 of good tobacco. 



PRINCE RUPERT'S DROPS. 

(Tolhs HiUtur) 

Rm. — Having read In your valuable Magazine, two 
articles respectinf^ Rupert's drops, which T think 
very erroneous, 1 have ventured to write to ynu on 
the subject. Your correapondcnt in page 182, 
•Intes, that if Rapert** drops br thrown down 
fnrribly upon tri^h, they will recoil and not hrrnk. 
Now ftAer reading this statement, I made a dozen 
and tried them in the mnnner described, wht-n only 
three out of the dozen recoiled ; and those three in 
being brought a aecond time in contact with the 
flags wont to shivers. 

Page 239. article " Phenomena of Glass," reads 
rthns : — Ttie glass in a melted stute, when dropped 
" ito cold water, by its gr4--at heat derompoaei it, 
[and at the same time immMlintely contracting it, 
'ftHTns into a drop, inclosing a mixture of oxygen 
■nd hydrogen, derived from the water. Now, in 
making Rupert's drops, the metal or melted glass 
never alters its form from being dropped ufT the 
Iron rod ; nor can it inclose a mixture of oxygen 
and hydrogen, when the water docs not attracC the 
■nrfare of the glafls ; but if melted gins-i be droppett 
into water in any other form than that of Rupert's 
drops, the surface is instantly attrartedby the water, 
and is fractured all over, so thnt you may reduce it 
lo powder with your fingers ; and even Rupert's 
drops, if they be either too hot or too cold when 
dropped into the water. If they contained oxygen 
and hydrogen, woiUd not heating tbem to a malting 
slate ignite the gas and ciiose them to explnde ? I 
have nKltrd them at the ttame of a candle, and at 
thf blrtw-pipe jet, iind drawn them in two without 
atiy explovion, and yet tlM<y broke in tlie usual way 
iftxrwards. 

My idea is, that the drops by being so quickly 
congealed, eaases a number of minute fnicturrs 
iuMde, and as Konn afi the end is broken off. the 
air mshen in with »uch furce as to break it to pieces, 
■nd at tlie MOM tine impartlBg a shock to the hand. 

THOMAH BOWES. 

Pvrt Dmnitu. nmr Gtaagom. 



MEMORANDA. 

Lunatict. — Of the inftnenre of the planst* mii! 
the moon — notwithstanding th« name ol luns&n, 
and the vulgar imprcsaioiU'^no pnmf wHstmr 
exists. Yet physicians of eminence — Me»d ertii— 
have said, " the ravings of mad people kc)>t laait 
periods, accompanied byepileptif fits." The bimis 
apparently is equally iouocencof Che tboanadthtip 
ascllht'd to her. When the paroxysms of mad pao- 
plc do occur at the full of the mnoo, Dr '»■!'— —« 
inclines to explain the matter ihu* -. — *' > 
in general light sleepera ; therefore, \\V' 
which bays the moon, and many other animtU, n- 
roarked as being always uneasy when it is it tlie 
full, they are diiturb*^ by the flitting ' 
clouds which are reflected on the eait, 
rounding objects. Thus the lunatic convrnat 
dows into imai;es of terror, and, equally 
' whom reason lights not.* is filled with ali 
bectimes distre&sed and noisy.'* 

We»t Indian Coal. — The coal raised froiD (te| 
mine discovered a year ago, about six milu fmn I 
Havana, has been tried by the Spanish st 
frigates, and pronounced by the engine*^* tn 
ccllent in quality — superior to the beat 
Anoiyiis show* tlte roal to consist of the 
parU:— Carbon, 71-7-I ; oxygen, 6-32; h| 
8-44: 13- ashes 50—10000. The railroad 
the port to the mine is in rapid pnigress biwarft' 
completion. As the bed is believed to be vi 
IciiaiTe, the enterprising proprietors 
handsome profits on their outlay wht 
^^'est India steamers shall regularly call at Hi 
for a BUpply of furl. 

Derhtfhhire Diamondi, — IVrfanpa it may not 
generally known tliat the Peak of Derbjshtn pf«*{ 
dures what arr termed Derbyitbire diamonds j 
are small detached and perfect crystals of 
quartx, of an hexaifUDical prism terniiiiatrd pyi 
and others of a lighter color ; they am often 
at Bakewell. BrassingtoD Common, Rnxton, 
ton, snd Dnrlry Oale, and are greatly lai 
after, and murh usrd hy the lapidaries of fiirnung* 
bam, Derby, flw. — Shfjlicld Iris. 

firt and Water Proof Crtment .—Vowt ■ pintffj 
vinegar into a pint of milk ; when the latter 
fully confculated, clear it off the Ivrapa, and let ttj 
settle, then mix the wbule well tngeCher ; nov 
into the liquid quicklime* till npon siirrii 
whole we obtiim a thick paste. This cemei 
permanently unite marble, eartheuware, cfai 
— FVeneh Paper. 

Drvtructitm of a City by an Earthfuci* —1 
Icttrr reneivrd from Central Ainrni:a 
Jamaica packet, it appearathat the et> 
Cartago, containing a popohition of 10, (in 
was destroyed by an earthquakr early \t 
ing of Sept>*mt>er 2d, though, as Mutriy iii t* 
huil(liii|c«, tiTf very liiw and rnm|K>sed of « oi'tl, snl 
as the intiabituots had previously risen, but tf 
(not more than forty or fifty personoi were kUM 
or wounded This eirtliquake cvcurr«i withtful 
previou^jlgamini:, and was connected with an rrnp* 
tion of thp \vrlI.knoK-n volrano about Ibrre i« 
dintant, \ mnurt shock of the »iime carti 
was nt the same time felt in the town of imki 
not far iiikr«nt, at which place the eafUl M 
fur several riayR sub«cqucfttly. hut ool tnachi 
wai done there. 



Lo«DO»._Pnni#d l»y D. KaA«ei>. S. \Vbil« H-iri* Unc. Mils Hnd^PubhtlMil hy W. MairTAin. 11- ^«tp^MM 
ifmmunlcaUuiu. (wlilcb arc aaiwcred Mouthly . ) lo Imp addreascd lo lh« E4i|tir. at tT, CotU^* Crov#. Mlta 



THE 



MAGAZINE OF SCIENCE, 



anb Sri&ool of arW. 




^ 



MAGAZINE OF SCIENCE. 



W. E. WIGHTMAN'S LATHE. 

Thi follovin; account of tlu* initnuuent is thus 
dcKortbed by hiuiielf in llebert't *' Engineer's 
Encyrlopirdia," page 622. " Peeling tfisarcd that 
it may prorr of the most eminent service to me- 
cbanics. as the arrangements are extramrlj simple 
and eaiily understood, sod the construction such 
as tny tolerable workman can accomplisb, and avail 
bimsell of tbe advantages it otTcrs, at a moderate 
cost. 

"Fig. 1 represents tbe lathe, with the cutter- 
frame fixed in the compound sliding rest, ready for 
use. A. the triangoliir bar on which the macbine 
is mounted. B B, two plllnrs whirh support tlie 
bar; tbe parts A & fix it to the Uthe-frame. C\ the 
head ; D* the puUey ; E, the mandril ; e, the screw 
on which the chucks are fixed ; F, the cutter. frame ; 
f, the cutter; G, two wheels, which give a slow 
motion to tbe cutter-fraroo; K, tbe rod and handle 
of the slow motion ; 11, two heads or puppets, in 
which is 5xed the apindle K of the cutlcr-frame ; 
L. a bar of steel, on wliich tbe puppets are fised, 
and which also fastens the cutter'frame to the com- 
pound sliding rest, by passing It throug;h n hole In 
tbe tool-rraaie, as will be set-n on reference to the 
figure, the part Y removing for the purpose ; M, a 
groove turned on tbe edge of tlie catter-frame, for 
a string to work on ; O represents the frame, or 
0fer>bead motion for double stringing tbe lathe; 
P, a moveable pulley, whereby it muy be fixed per- 
pendicubirly over tbe culter-frame; R K K, the 
pulley's siring and weight connected with the frame 
O, for double stringing the latbe ; T, the index to 
tbe division-plnte ; S, one of the two screws for 
changing the rectangular pofiltion of the compound 
sliditig-rest to an ubltque. S, Figs. 2 and 3, re- 
presents the slide of the cntler.frame ; and H, 
Fig. 3. the screw, whereby the slide is moved ; G, 
the screw for fanteniDg tlie cutter. Fig. 2, Js an 
enlarged view of the cutter-frame, when removed 
from the rest. Fig. 3, rcprei>ents the face of the 
cutter-frame ; Fig. 4, tbe bnck of it, with the 
wheelfl of the band-motion. The letters refer to 
the same partti in all the figures. 

"This machinery is intended to supersede the 
UK of the eccentric chuck, by ft58uming a more 
natural and easy method of engraving, by the too) 
or cotter tracing tbe work, instead of the article 
doing it that ia to be oroamented. By this im- 
provement, the action of tbe tool is more diatiactly 
leen than could be. by the movement of tbe chuck, 
especially after a few circles have been cut; for, by 
their rotation, the eye (particularly of an amateur) 
is soon fatigued, and yet to these inconvcniencca a 
turner most continue to submit, if no better method 
could be contrived. 

" The principal adrantages of the present inven- 
tion are tbe following : — At a comparatively trifiitig 
expense, (to the costly macbinrry now in use.) a 
turner may be put in possession of an apparatus. 
wliich will answer all the purpoaea of eccentric and 
cycloidul turning, and which will, at tbe same lime, 
form a complete drilling frame. As an apparatus 
intended to supersede the use of the eccentric 
chuck, it combines many advantages, amongst 
which, three may be mentioned that are of im- 
portiince :— tst. As all patterns are worked by the 
divisions of the plate on the small wheel of the 
lathe, a much more extensive variety of circlea can 
be obtained, than could be by the divisions of the 
eccentric chuck. 2d. By sUckcoiog the screws 



S S, in the large slide of tbe compoond sUding-resta 
a change may be effected from the rectangular posi- 
tion of the cutler-frame to an obLiqae povitioat 
and, after the proper angle is obtained, (the acrtw 
bring tightened,) tbe segments of circles cms b* 
worked round a centre with greater accuracy than 
could be bjr tracing ortr patterns, which I believv is 
the common method ; while the alteratiuo of ny 
machinery, for such purpose, would scarcely occupy 
a minute of time ; an object which is of no small 
importance for the dispatch of bosineaa. 3d. Tti9 
loss of time in centering the work, occasioned by tbe 
necessity of removing it from one chuck to anolber, 
to receive the different ornaments, (an evil scverslj 
felt by turners,) is obviated by my improvemenl | 
as also the great difficulty, so often experienced \a 
getting the/ace of tbe work to run true again, sAw 
taking it from one chuck to another ; from Uair 
liability to get out of truth by the wcanng of tke 
screws in fixing them to, and removing them frooa 
the spindle of the lathe; in which case every- elTart 
at fine-finifbing would be inevitably defeated. 

** To apply my upparatua for cycloidal tomtfig* 
tbe addition of a rod is required to connect tU 
cutter-frame with tbe univerul chuck, after ii n 
screwed on the spindle of tbe lathe ; but whirb, on 
account of its connexion, (being a bad drsu^tilt- 
man,) 1 am unable to send, Tbe following descn|i- 
tiun will, 1 hope, make its construction ap] 
sufficiently intelligible : — ^The edge of the 
the universal chuck, (the machine on w 
work to be turned and ornamented is fixed, 
which is a common appendage to all lathes,) 1 
divided into 144 equal parts, which form a w 
and upon tbe face of the left-hand head of the 
U fixed a piste, and a corresponding one 
side of the rest, through whiuh tbe axis of 
connecting the chock and cotter-frame rev 
Now, if npon the rod is fixed a wheel of 
teeth, working on the wheel formed by the 
the universal chuck ; and if npon the other 
the rod Is fixed a wheel of tbe same siie and 
ber OS those which work the cutter-frame, nad M 
work in one of those wheels ; then it mott Vl 
obvious, that, by tbe chuck revolviug once 
wheel of twelve would make twelve revol 
which number would be given to the cutter-fi 
thereby tracing an accurate circle of twelve eye 
Attain, by changing the wheel of twelve to aoolba 
of proper proportions of 144, a number of cycloiil 
would be described equal to that proportion, 
by sliding tlie connecting-rod out of gear, 
moving (be universal chuck any number of 
forward or backward, tbe cycloida would beaai 
intersect each other. 

" It may, perhaps, be unnecessary to 
this, and tbe ercentric apparatus, must be wi 
by the hand-motion of the cutter-frame. 

" To change it into a drilling frame, all 
required, cotisisis iu throwing all the wht^ls 
gear, and passing a string over the groove 
cutler-frame, to work on tbe pulley P. wl 
fixed on the same arbor as the pulley uaed io 
stringing a lathe. Then pass a siring, (which 
be kept for the purpose,) over the lut-men 
pnllry, and under the large, or fly-wheel ( 
lathe ; and after tbe drill bos been fixed ia 
aockel of tbe cotter. fnime, and adjusted to rn 
true, or central, tbe machine will be ready fur 
Now it must be clear that, by working the 
of the lathe, as in tumiog, A rotatory motion 
be given to tht; cutter^fruae f aod after the 



tba 



Tbrti. 



tltf 



MAGAZINE OK SCIENCE. 



323 



kneed to the work, tlirn, by nioTinft the 
igbl an^U slide of Ihr^ rtFt, > ifratght line 

billed, of a length in proportion to the 
t of the slide. Then rliange the diviaioo 

1e on the Rmall whrcl of the lathe, and if 
line wii? cut from the centre, tlwn cut tho 

e centre, nnd to on till the whole ii com- 
ben a beantiful circle of ttraigbt lines would 
>n a centre." 



BRVATIONS ON IGNIS FATUU8. 
cuAMsaiu, Kfta., r.t.s. p. 2. a. 

ffod bffort t]t€ Linn^an Sucirty.J' 

the optnion ef ntny naturalists, that 
appearance known by the names of 

iTis, WilUwith-the-wisp, and Jack-o*- 

not a meteor, as generally aappoaed, but 
His instrct ; and. in confirnmlion of this 
|i, I have collected, not merely the opi- 
tl the eiperience, of many persons who 
'^repeated opportunities of obaerving this 
ibenomenon. 

year 1814, 1 bad a conYersation on this 
Itb ay eateemed friend, the late Mr. James 
the celebrated botanist, who informed me 
Ut confideat the Ignis Fatuus wag not a 
Ut a luminous insert, for be had seen it 
a. plant and fly off again. The same, lie 
3 been witnessed by his friend Mr. Curtia , 

the Flora Londinentit^ My curiosity 
itly eicited by these remarks, I went im- 

to my father, the late Mr. Anthony 
, who, having lived for many years in the 
Itiood of Lincoln, where the Ignes Fatui 
mtly aeen, waa likely to afford me infor. 
I the subject. He told me that, when a lad, 
in the dusk of the evening ihruugh Bul- 
led, be obwrrrd behind him a Juck-o'- 
liioh followed him through the wood ; and 
luminous ap]>earance came to the gate, at 
r the path, it rose to clear the upper bar, 
into the adjoining meadow. At another 
observed, in the aame neighbourhood, two 
tiU-witU-the-wispsllying about each other, 
rat play, which they did for a cooaiderable 
mt last settled on a furze bush. 
Rnarka corroborated the opinion of Measn. 
bd Curtis; and, on refriring to the TYan*- 
^ the Rnyai Societjf, toI. r., there ia a 
•tion on the same subject by Derbam, 
•— " It being the opinion of divert skilful 
I, parliculnrly Mr, Francis Willughby and 
Ihat the Ignes Fatui are only the shining 
t number of tho male glow-wonna, in 
^of the Pyradatc in Italy, flying together. 
kbaerviiliuiis I made at a place that lay in 
Itween rooky bills, which, I suspect, might 
tinerali. in some boggy ground near the 
' thoac hills. Wlien seeing one in a calm 
^ with gentle approaches 1 got up by dc- 
fcin two or three yards of it, and viewed 

tbe care I possihly could. I found it 
bout I dead thistle, growing in the field. 
all motion of the air (even such ns was 
tbe approximation of myself) made it skip 

place, and thence to another and anu- 
t ii generally uUuwed tbat the male glow, 
igblly luminous, yet not anllicuntly to to 

appearance mentioned by Derhum. Tbe 
emarks by Mr. Arthur Aikin, in his 7Vmr 
Ta/ee, wiU aomewbat elucidate tiw sub- 



ject : — " I was not a little surprised to see me glow- 
worms, Rt our appronch, darting over the hedget 
into the field<t. Knowing the feniule alone to be 
lummons, ond, at the same time, destitute of winga, 
this phenomenon puzxled roe a good deal : nor can 
I account for it, except upon the ouppuiitioa of the 
male bearing the female through the air when in the 
act of their amours.*' Wishing to obtain all the 
information 1 could on a subject so interesting, I 
spoke of it to my kind and intelligent friend, 
Thomas Stothard. Esq., U. A., who, bcsii1r« poc- 
aeasiug talents of the highest order in every de- 
portment of art, is an excellent practical entomolo- 
gist. From this gentleman I received tbe following 
letter :— 

■ Junt IS. IS23. Aetraua Sireil. 
" My good Sib, — Agreeably to your requeat, I 
send you the best account my recollection will sup- 
ply of the Ignis Fatuu3 we conversed about when 
last together. Aa I was returning from Plymouth 
early in June, 1821, having travelled all the preced- 
ing day and night, and had passed Blaiidford early 
in the morning, considerahty before iunriiie, when 
objects were just diittioguishable, I aaw what wu 
new to me, and which fixed all my attention, for 
the short time allowed to observe it while mounted 
on tbe outside of the coach, passing at the usual 
rate of 7 or 8 miles an hoar. On my right hand, 
and tbe aide on which I was placed, at the distance 
of -10 or 50 paces, appeared an irregular light, 
bounding or ri'^ing to tbe height of 3 or 4 ft. over 
Bome heathy shrubs, which covered the high and 
manby ground spreading to a great extent : amongat 
these it sank and reappeAred with a motion aome* 
what between flying and leaping. A friend, who 
was with me, observed it, and exclaimed that it waa 
the third appearance of the like phenomenon ; and« 
requesting him to give me more information, he 
answered, that, when travelling the Hath road on a 
similar convryance, nt the tametimc in the morning 
and aeason of the year, he observed one, though 
not so distant from the road as the one we had 
passed ; its flight was in the same direction with 
the coach; and several times it alighted on the 
shrubs or high grass on the border of a wet ditch 
near the road tide. The experienced ooachmau 
pronounced it to be a Will -witb .the- wisp. 

•* Yonrf , dear Sir, very truly, 

** T. STOTHAftn." 

Mr. Stothard waa of opinion that the 8oppoee<l 
Ignis Fatuus, from iUt motion between flying and 
leaping, ia the mole-cricket. He brought one from 
his cabinrt, and pointed to the structure of its 
wings, in proof of this conclusion ; for it could not 
fly high, nor long together ; and the habitat of tho 
Gryllotatpa being tbe same as where this luminoiu 
appearance la usually seen, is another coincidence. 
In the aeeond volume of Mr, Kirby's JnSrodtictian. 
to EiUomoloj/jtf be relates a circumstance corrobo- 
rative of the above hypothesis: — "The Rev. Dr. 
Nutton, of Norwich, whrn he was curate of Tikleton, 
Cambridgeshire, In 1780, a farmer of that pUce of 
the name of Simpringham brought to him a mole- 
cricket, and told him tliat one of his people, seeing 
a Jack-o'-lantern, pursued and knocked it down, 
wbea it proved to be this insect, and the identical 
specimen shown to him." 

In tbe admirable work just noticed, its learned 
author, who strongly advocates the opinion of theM 
supposed meteoric appearances being luminous in- 
teots, gives tbe following iatercatinc fact: — "Mr. 



334 



MAGAZINE OF SCIENCE. 



Shfpptrf), trdTi^iiig ODfl Diftht. bctweea SUmford 
ADd Gmniham, od the top of the itafe, observed 
for murr tbsu ten niiimtr* ■ verjrlugc IgniiiFitniu 
in the tow mnnliy groundfl, which hadcTery Appear- 
•ore ol' being ao insect. The wind wu vcrj hi^h ; 
couae4ueiilI)', Lad it beeo a vapor, it muit have 
been carried fowanl ia a direct line ; but this wai 
not the case. It had the same moliouB as a lipuU, 
fljiiig upwards and downwards, backwards and 
(ornsrdi ; sometimes appeariug as aetUcd, snd 
•onittimes as hovering in the air." 

In ibe summer of IH26, 1 went into the fens of 
Lincolnshire, hoping to lee an Ignis Fatuus; but 
in this 1 was disappointed. Frpm Joseph Simpson, 
an intelligent fisherman at Frtcston Shore, near 
Boslun, I oblstned the following information ; — 
That, before the fens were drained, bis father had 
wen a doxcn Ignes Fstui, ftpparenUy playing with 
eiKh other like inarcts, Ibe highest not more than 
cifflit or ten feet above the ground. He told me 
that, since the draining of the fens, they were not 
ftO common ; yet he and several others had seen one 
settle on a hedge, and ou a post, and fly off again ; 
nod that it appeared to bjm to have a voluntary 
inotion, for he noticed one flying towards a hedge, 
then rise and pass over it. 

Myfiicnd Mr. Cole, surgeon, of Charlotle Slreetf 
Bedford Square, has favored mc with the following 
particulars on this interesting but obscure subject : — 

" lu October, 1823, I went to Worcrster. and 
was met hy a young man, in the servire of ray 
father, who came there with a gig to drive me to 
Lei^li, near Mnlvern. Having beard that be had 
seen a Will-with-tbe-wisp, I took the opportunity 
the drive aflbrdud, to iut{uire about what he had 
aeen, when he stated a.t fallows : — * 1 was coming 
home with the boy from looking after the sheep, at 
Ute furtlier side of the farm. Our path lay near a 
hrdgc ; and on a tiuilden there appeared at a dis- 
tance a ball of Are about aa big as my head. We 
stopped ; and it came directly towards us. The boy 
abkcd me what it was : 1 tuld him I supposed it 
must bo wliat they called a Jack-o'-lantern. It bad 
« dancing kind of motion, and advanced under the 
hedu;e side, till it came quite near to us ; it then 
diviiled into a duxen or twenty parts, forming so 
many balls of firei about the size of my fist, which 
flew apart from each other, and pbyed about for a 
abort time. They then joined together again into 
one large hall, as at firnt, and turned over the hedge 
into the next Acid. It passed betwe<?n two oak trees 
that stood at some distance from tlie hedge, and 
then went straight across the fieldi, rising uvcr the 
hcdf;c8, until it disappeared in the dislatwe.' In 
reply to my questions, he stated that it was in the 
spring of the ye4r. and that the night was about as 
datk OS it was at tlie time he was speaking, a cltrar 
moonleis night in the beginning of Octttbert about 
ten o'clock. To an inquiry whether he thought 
the motion of the object he saw, especially wheh it 
divided, and played about, and then nnited again, 
was like anything he bad seen before, be replied 
that be did not know ; but, when afterwards OAked 
if he thought it like the playing of flics or gnats in 
tlie sun, he said it was preciisely almiliir. The spot 
where lie saw it was shown to me. The soil is dry, 
and the tituation is slightly elevated above the sar- 
rouui-ting country : there is no marshy or swampy 
ground m the neighbourhood. Tlie man's name is 
VTilliam Day. He was brought up in my father's 
family, and r«i'lrt there still.'' 

1 h&\e %uestiuucd maay pcrsous who have seen 



the Ignis Fatuua, besides those whom 1 have isstt* 
tioncd, and they invariably concur in its having t 
voluntary motion, fljriug backwards and fur^uds, 
rising to clear hedges, resting on gales, psict. and 
otlter objects that lie in its route. From the fiutt 
I have been able to collect, I thiuk we may Iftfes 
that many more inacctJ ore luminous than aaCimllfll 
have imogioed ; and, should ihciir obscrvfttioM Bit. 
be sufiScient to convince naturnlists that the n^ 
posed Ignes Fatoi ore really and truly insects, pi 
I anxiously hope that the remarks I have made WUf 
be the means of leading gentlemen, who mid« ta 
favorable situatioiu, to investigate this curimi 
phrnomeoon. 

[There undoubtedly appear considerable groo&ii 
for 8upi>OBiog that the history of many ca s es gC 
Igoea Fatui may be connected with the bgfat emiltti 
by certain insecls ; but, at the oamc time, theft k 
strong evidence opposed to the uaiverMl adoption 
of this explanation. For observations on 
subjectt see Jameson's Edinburgh / 
January, 1833, and BiUumoloyieat 
voL i., p. 350. — BD.] 



WATER-PROOF CLOTH. 

(In ATuterr to a t\jm!»pbTuimt. J 

A PATCNT was obtained, in August, IH3Q, by Mr. 
Thomas Hancock, for rendering textile fabrini 
pervious to water and air, by spreading the 
juice of the caontchouc tree upon the atii 
the goods, and then espoaing them to the 
dry. It does not appear that this project has 
realised in our uianufuctures. 

Mr. William Simpson Potter proposes, in Us 
patent, of April, 1U3.'), to render fabrics water- 
by imbuing them viib a solution of Istnglasa, 
and soap, by means of a brush applied to the 
side of the cloth, distended upon a t«ble. 
is dry, it must be brushed on the wrong side, i 
the grain. Then the brush is to be dipped 
water, and passed lightly over the cloth. The 
caused by the above application can be tJi^rt 
brushing the goods when they are dry. 
jtrepored is said to be impervious to wat^- 
to air. 

.Mr. SteTier*s plan of rendering cloth w*ttr-ppMil« 
for which he obtaioed a patent in 1^ 
consists m spreading over it, with a 
of lndta>ruliber in spirits of turjir 
mure applicntionsi and then spp 
solution mixed with acetate of Icn . 
phate of sine, gum maatic, or other dryin, 
lie next takes wool, or other textile m-. 
into proper lengths, and spreads it upon the- »uilsc« 
of the fabrie varoiahed in this manner, for tto 
purpose of forming the nap or pile. He Ihsa 
pres^rs the cloth by means of rollers, or braahMt' 
as to &X. the nap firaly to it* surface. 



ON THE BATE OP MAN'S EXIl 
ON THE SURFACE OF THE Gl 
While the rciiearcbrs of guotugista a< 
proofs of the antiipiity of our planet, and C 
wrie:§ of revolutions by whirh its surface 
come modified ; while they tench us. by apj 
to the silent hingunge uf their rrbfjum ())-«( n 
organic beings have tensntet) (he l. 
to the existence of our contiueots »: 
time when iU surface exhtbitefd aoon^WUou, w( »l 
we can form only a plauaihle conjcctarv, ifitt d 



MAGAZINE OF SCIENCK. 



325 



Uc« era the fsithful records ; while 
iu that BQccrtaive eru biiTc taken 
an tiie fragments recovered from the 
-ulnneum of Ndture, enable ui to deci> 
lipro^Iyfiliicj which announce the progress 
Ml, — they Assure us tbst Man is but of 
AatCf the ultimnte of animalii chIIciI into life 
ling. It would appear to be now well es* 
fd, that, in none of the older strata, in none 
X ftfc termed secondary fartnations, in none 
tertiary formations, in none of the regular 
if Cbeglobr, do the fossil relicauf M in occur, 
beds, which contain tlie remains of ancitrnt 
Ehe typea of forms blotted out of creation, — 
t the deposits containing Ibe bones of Ele- 
mnd Kbiuoceroses, which have now their 
rvprcseniatiTes, we search in vain for the 
remains of oar specirs. Once, indeed, the 
>caes of fjttinct animals were regarded as 
f and philosophers speculated upon the 
of 8 race more mighty Omn the Anakim, 
eh these were deemed the relics, — an error. 
:h we now imile. " Many of the labourers," 
urier. "in the gypsum quarries about Pans, 
I, iW the boues, which occur so abundantly 
ID, are, in a great meaaure, human ; but 1 
iMa thousands of these booes, and I may 
ifinBi that not one of them has ever belonged 
' SjKCie*. I bare exarrined, at Pavia. the 
I of bones brought, by Spallaiuuini, from the 
of Cerigo ; and, notwithstanding the assertion 
: MiebrAted observer, \ affirm, also, that there 
one among them that could be shown to b« 
u" 

s not, bowcTcr, affirmed, or pretended, that 

lil reUcs of ^lan have been found, or may be 

—(or the eiiitence of such is aicertained ; 

ej do not occur in such formations, or under 

MndUions, as indicate his roatcmporary ei- 

p with the Palieotheria, the Annplotheria, or 

!' -in, — the Mammoths and the Bdasto- 

>irir situation is such as to corroborate 

ii, from other proofs, that Man is a new, 

illy speaking, a recent dejiixen of tbs 

ir planet, 
tt rcmarkftble fossil remains of our species 
whidt occur in a tufaccous deposit, of 
ite, and daily increasing, in the island of 
ipf ; n file specimen of an almost entire 
I in bis calcareoas matrix, is in 
-n ; anotber (see Pig.) is in the 
I .^ri.^. In both, the akull is wanting, 
fossil skeletons of GusUaloujte, as Cuvier 
I, all more or leM mutilated, arc found near 
At Mf'ule, on the north. west coast of the 
and of Guadnloupe, in a kind of slope, resting 
It the sterp edges of the Ulnnd. This slope 
a great measure, covered by tho sea at high 
, and i» foaml to be nothing eUe than a tufa, 
dj snd daily augmented, by the very small 
shells and comls, which the waves are 
ly deliiching from tfae rocks, the acruma- 
of which assumes a great degree uf co- 
the places that are must frequently left 
u found, on examining th<>m with a lens, 
inX of these fragments have the same red 
part of the cnraU contained iu the rrcfa of 
id. PormationFt of this hind nrc common 
s whole arrhipelo.'O of the Antilles, flhere they 
to Negroes nndcr Ihe name of Maf;onne- 
Tbeir augmenlatioii is prnportionrd tn 
vS tho surge ; ud thry have greUlj 



extended the plain of Cayes, in St. Domingo, in 
which sometimes are found fragments of earthen 
vessels, and of other articles of human fabncutinn, 
at a depth of twenty feet. Various conjectures 
have been made, and even events have been ima- 
gined, in order to accouDt for the depositimi of 
tbeee akeletone of Gaadalovpe. But, from all tba 





circumstances of the ease, M. Jonn^, corrr<pondeat 
of the Academy of Sciences, who has bera ou the 
spot, and to whom Cuvier is indebted for numerous 
details, thinks, that they are merely bodies of 
persons who have perished from shipwreck. Tlieir 
discovery occurred in 1H05. In the rock, which 
innms these bones, M. Koenig detected fragraeota 
of Miltepora miniacea, of several Madrepores, as 
well OS the fragments of shells, which be compares 
to Helix acuta, and Turbo pica : and Cuvier states 
that, in the specimen at Paris, which was sent there 
by General Donaelet, there are embedded shells of 
the neighbouring sea, snd land shells, which are 
still found alive in the island -, nomely, the Bulimua 
Gnadaloupensis of Fernssac. Sir Humphry Davy 
subjected small portions of the skeleton in the 
British iVIuseum to cJiemical analysis, and foond 
that the bones contained part of their animal nattefp 
and all their phosphate of lime. 

Independently, however, of the existence of fossU 
reliquia of man at Guadiloupe, human bones, but 
scarcely to be termed fossilized, have been found io 
other ploses. They not unfrrquently occur In 
caverns, or fissures of rocks, mixed with articles of 
human fabrication : they are sometimes found in 
such places, buried in fine mud, beneath a layer of 
stalsgmite, and sometimes incrusted in the Istter. 
In these cavt*tt and fissures, where the wandering 
savAgM of n thinly-peopled country might occa- 
sionally find refuge, or into which they might have 
been accidentally prccipitnted, are found the remaina 
of many eitinct Mammalia; vis., of extinct speciet 
of bears, of hytcnns, lioos, or Urge feline animaU ; 
deer, elepbontj, hippopotamaves. flee. ; as well aa 
of animals now extaut — horses, oxen, sheep, dogs, 
wolves, end foxes. 

Thus, in the cave of Gaylenrcutb, there occnrred» 
arcording to Roseumuller, the bonea of men, horses* 
oxen, shci-p, deer, roea, miilps, badgers, doga, and 
foxeii bestdci the booec of beuSt liyvui, ud 



326 



MAGAZINE OF SCIENCE. 



tigeri; but. froiDD the reie&rcbet made by him, ia 
the csve itself, and from tlic state of preservation 
in which the bones of the former animals were 
found, it waa erideot that thcj mujit have been 
depofnted at periods mach more recent than those 
of the latter. lu aume of the grottut's of the care 
of KlHOBtein, M. RoBenmi'iller, found two haman 
skeletons, superficially placed, and incrusted with 
atAlsctite, — a pruof of their modern deposition. In 
the celebrated cave of Rtrkdale, in Yorkshire, in 
which bones of the elephant, hippopotamus, tiger. 
byirni, wolf, Ac, occurred in abundance, many of 
them bearing the marks of the teeth of the aniinaU 
that had gnawed Lheoi, and interallied with the 
excrcmeuld of the hysna, no human hones have 
been discorered ; but, in the caves of Favelanci, in 
the county of Glamorgan, at the entrance of the 
English Channel, the clergyman and surgeon of the 
. neighbounng Tillage of Poriinan, found tbe skeleton 
of a woman, together with bones of the elephant, 
rhinoceros, horse, bear, hysena, fox, rat, and, also, 
of birds. Many of these bones, however, were 
modern ; and the diggings, mndo at remote and 
unknown periods, hid displaced the ancient bones, 
and nut only mixed them with tbe modern, but also 
with shells of tbe present sea. It ia to be re. 
gretted that, upon the disoovery of caves containing 
bones, persons, anxious to examine them, yel tittle 
aware of the importance of leaving them undia- 
turbed in their respective situations, for the investi- 
gstion of the geologist, begin to dig, and collect, 
nixing them together, so as to prevent tbe posai- 
bUity of ascertaining their respective order of de- 
position. In the celebrated cavern of Adclsberg, 
in Cnrniols. the Chevalier de Lowengreif disctovered. 
in 1B16, a hole in one of iU walls, at the height of 
fourteen fathoms : this conducted him to a series of 
new caves, of vast extent, and of iocoropsrftble 
benury, from the lustre and variety of their staliu;. 
tites. A part of these caves, however, it is proved, 
must have been formerly known, and either are, or 
have been, accessible by some otlier entrance ; for 
inscriptions were found in them, with dates from 
13(t3 to It'p/fi, together with humnu bones and rnlire 
carcasses that bad been buried there. Through these 
cavea, M. Volpi (Director of the School of Cora- 
roerce and Navigation, at Trieste) as»crts his bsving 
proceeded for more than three le.iguea, almost in a 
straigliC line, and that be was stopped only by a 
Jake, which rendered it impossible to go on. It 
was about two leagues from the entrance that he 
disrovered bones of animals, which he describes 
under tbe name of Palicotberia, btit whiL-b belonged 
to the extinct bears, whose remains occur in the 
bcar^caveit of Germany. The remains of Man, there- 
fore, found in tbe caves which contain, with the 
bones of recent animala, those of extinct species, 
prove nothing in favor of the contemporary existence 
of the latter and tbe human race; any more than 
the circumstance of fniJiTig the coins of the present 
century with those of the Saxon era, or of ancient 
Koroe, at tbe bottom of a pit, or lake, would prove 
B coincidence of time in their fahrieation. One 
thing, however, is clear, thot, ot tbe period when 
our Cuiitincnt bad assumed its present general form, 
it was tbe abode of species of Mammalia which have 
passed away, and whose representatives now live 
only in the butter regions of the globe. The cir- 
cumstancea attendant upon their drpusition in these 
caves, where they are often found in recesses, the 
entrance tu which could nut have admitted the living 
animal, iovolve many speculations : but the subject 



is alien to our present purpose ; nor do vre 
to be able to throw more light npon it tliou has 
dune by our learned and zealous geologtsta. 

AVc may here allude to the fossil humnn r.!i.'« 
found near Kosritx, and said to have bren 
consolidated in the limestone rock, Uyj: 
the remains of the rhinoceroa, Uon, hyaaaA, 4«- 
M. de Sdotheim, by whose these organic reooaai 
were discovered, tlirows a doubt upon this point, 
and considers the human bonea to have teen dr. 
posited at a later epoch tban the bonr" of tka 
animals refrrred to. and in this opinion be its bome 
out by Dr. Haclclend, wbo observes, that ' i!.: ,t*e 
of Koaritx affords no exception to tbe ^' 
that human bones have not been discovt 
of tboie diluvial depodts which hare hitherto bc«a 
examined." 

Tbe discovery of htiman bones !a peat-bogi, ig 
tumuli of unknown antitjuity, in mines, &c., dofl 
not bear upon the present subject. 

The opinion, then, of tbe best Informed and 
observant geologists, is. that Man is of recei 
tion, — that he was called into being when the 
of tbe earth, having undergone a seriea i 
cations, and having assumed, on a broad 
present aspect, beeame tilted for his i 
Against the opinion of his comparatively 
date, some philosophers have hrnugitt tbe ch 
gical records of the Chinese and Brahmins, 
presumed zodiacs of tbe ancient Kgyptiaos. 
respect to tbe fabulous chronology of the i 
and tbe Brahmins, ic Is unworthy of serious 
OS evidence in the case. With respect to the 
of tbe Egyptians, it is now, we belirve, ad 
that the great temple of Deadera, whence Lt 
brated zodiac, now in Paris, was obtained, 
anterior to the time of Augustus : tbe small 
of Esn6, that of which thu origin, as iadlctf 
the zodiac there discovered, was, according 
lowest calculation, near 3,000 years anterior 
Christian era, has a column sculptured and pi 
in the sixth yearof Antoninc, 147 years after f 
and it is painted and sculptured in the some stylt 
as the zodiac which is near it. 

These celebrated planispheres have been tbe ttit 
to which many philosophers have, as they thoaefit 
triumphantly appealed, in favor of the aotir 
our race. Dapius referred the construction 
zodiac of Dendera to an era 13,000 years 
present : and others, of no little learning, 
fallen Into conclusions as extravagant 
appears, that these zodiacs have nothing to 
the precession of the ci^uinoxes, or with 
ptaoement of the solstice ; they are not tnie 
nor were tbe Kgyptians profound as 
Cuvier observes, that ** a mummy-case 
brought from Thebes, by M. Caillaud, and 
ing, according to the very legible Greek 
upon it. the body of a yonog man, who 
nintb year of Trajun, 116 years after Christ, 
sents a sodiac divided at the same pointa 
Dendera; and all the appearances in' 
this division marks some Dsttolui^icat thei 
to the individual ; a conclusion which may, 
be equally applied to tbe division of the 
contained m the temple*. *' 

In fact, aa already observed, neither the Ubles 
tbe Chinese and Brahmins, nor the --' ]- -f 
Egyptian temples, are worthy of the 

attention. Thus, neither monumen:: _: 

ductions of man, discovered in turaoii, lo the 
of ancient citieSf or mines, worked at u uuk 



MAGAZINE OF SCIENCE, 



327 



icb as glasi ornaments, wespoas. tools of 
Bone, lUmped brickN, bticI the like, — nor 

eiCrsvagant u may be its prctenaioiis, — 
y,— throw back to a remole era the com- 

k of the rt'ititnctt of tbe haman men; 
ttsi^mcnt of 6000 years, ss tbe wengt 
fi04[ duriok; which man has acted his part 
■face of the globe, accords alike with the 

tof the geologists and the cosmogony of 
; writings. 



ATUS FOR EXPERIMENTS ON 
POLARIZED LIGHT. 

Rtfitcting PianvM. — Light msf be COD- 
Ipolarixcd by a lingle plate of any trans- 
dj without double refraction, such as glass, 
tebony ; or by a single surface of water, 
Be, Bad varnished body, or suy ordinary 
id Burfflce, But in selecting any plate or 

should be one which has a low dispersiTc 
Btive power ; for it is only in this case that 
Ited light will be completely poUrised. 
■ntimony, oil of casia. flint glass of high 

power, colored or stained glasses, are all 

for this purpose. A plate of thin welU 

prown glass (if with parallel surfaces, to 

better) will answer fur ordinary eiperi- 

hff BuntUex of Plate GIom*. — When ■ 
of light is required, which is frequently 
ispeciiilly when we use the microfirope for 
[ imperfectly transparent hadica, from oae 
plates of the clearest and thinnest an- 
• should be placed in a frame, having 
ices well washed and cleaned with fresh 
isther. Their edges must then be covered 
int or with wax, so that no dust may in- 
lielf between tbe plates. If the gloss is 
with little color, the light reflected from 
will be as bright as that reflected from a 
mirror, and will consist wholly of 
light, when the rays are incident upon it, 
olarizin^ angle. The light transmitted 
lo used. 

bi^ Sundlej qf Bitrmn Glaji*. — As it is ex* 

Ifficult to obtain thin plates of clear and 

even if we take flint glass, which is 

ible from its high dispersive power, we 

Itute in their pUc:c films of gloss blown 

)OsL thtuness, and place them in a trough 

tro p1at4:s of the tUiaoeat glass. The light 

md throQgh this bundle may be also used. 

ia^ BuTidlet fi/ Miea. — Take a piece of 

,trausparent mica, as colorless as possible, 

; into the form of a right-angled paralUlo- 

IMe sides ore parallel and perpendicular to 

passing through its resulting axes* Hold 

dge in a powerful vice, and with a lancet, 

-bladed knife, split it into ten or twelve 

IT more if necessary. Before taking it oat 

Ce, cover all its edges with a coating of 

roog cement, so that, after the laminie are 

from one another, they may have the same 

osition as before their snparotion. This 

mica films, when taken out of the vice, 

best means of fiolariztng light that 

but the light must be polarised by 

t plane parallel to cither of the sides of 

, The best is that which is perpendicular 

r passing through the resultant axes. — 

tfcosmicted through ibis buadle being 



aUo perfectly polarised, may be used witb grett 
advantage. 

Donbly'TtfracUn-g Crystals of gr^ot Thicknm. 
— When we can obtain a thickness of from three to 
six or more inches of colorless calcareous spar, it 
forms one of the moat valuable pieces of polarising 
apparatus. We have only to place on one of the 
■ides that contains the greatest thickness, a circular 
operture just as large as that the two images of it 
may not overlap each other. We shall thus have 
two circular areas of light which sre polarized, tho 
one in one plane, and the other in a plane at right 
angles to it ; aiid by means of a screen or « black 
wafer we can cover up the one circular space, when 
we require only one kind of polarised light. 

Douhiy •reacting Prismi qf Icftand Spar. — As 
It is not easy to procure large snd pure masses of 
loeland spar, a sufficient scparatiun of the images 
may be obtained, by selecting a piece with one good 
natural larfaoe, and grinding down the oth^r, so 
that tbe common iutersecliun of the two faces of 
the prism may be periien die alar to tbe axis or the 
plane of refraction, coinddent with tbe plane of its 
principal section. The color of the images may be 
nearly corrected by a prism of crown or Hint glass. 
By increasing tho refracting angle of the pribm, the 
separation of the images may be increased at plea- 
sure. The objection so often made to the use of 
prisms of Iceland spar Is not well founded, for it is 
copable of taking an admirable polish, equal indeed 
to its original surface ; and even if tbe operator is 
not skilful in the art, the polish may be made per- 
fect, and the surface preserved from injury, by 
cementing, on the two surfaces of the prism, two 
pieces of pure and parallel glass. When tbe prism 
is rendered achromatic, indeed, by u glass prism, 
the latter serves for one of the plates of gloss, sad 
oue plate only is retiuired for the other surface. 

SinyU Image Prisms of Iceland 5;/ar.— Prisms 
of this kind were first used by Dr. Brewster. Tbe 
method of making them is to roughen as much as 
possible the two surfaces, or even one surface, of a 
prism of Iceland spar, and to cover it with grooves. 
A fluid or balsam with the same refractive index 
as the ordinary ray, is then placed between the 
rough surface of the spar and a plate of glass. Tlus 
polishes, as it were, the surface for the ordinary 
ray, and allows it to pass through uninterrupted, 
in consequence of the spar and the fluid having the 
some index of refraction for that ray. The extra- 
ordinary ray, on tbe other hand, is scattered in oil 
directions by reflection at the separating surface of 
the grooves and the fluid, and totally disappears, 
leaving only tbe ordinary image. But as there it 
no proper oil or fluid of such a high refractive 
power as 1.654, it is better to take so oU of the 
aame refractive index as that of the extraordinary 
ray, for the surface which is roughened. If the oil 
does not exactly suit the surfiue, a slight inrlinatton 
of the prism one way or another, will produce the 
adjustment. When this is done, wc shall see the 
extraordinary image quite distinct, while the ordi- 
nary image has wholly disappeared. Fur ordinary 
purposes this prism is perfectly sufficient, but for 
others it mil not answer so well, as the nebuloOB 
light oeeo all round, is polarized in a pUne opposite 
to that of the extraordinary image. 

Agate Plates and Microscopes. — Among the 
bodies of the mineral kingdom, Dr. Brewster found 
agate to be one which gave only one distinct image, 
all the light of which is polarized in one plane. — 
He therefore uied it in hii ezpeiiments. Agate 



S38 



MAGAZINE OF SCIENCE. 



mieroMopci, or pUt«B of agste placed close to a 
single mtcroicopc, may be very •dvnaugeoiiily 
used. 

Tnnrmaline Pto/».— M. Blot and M. Seebeck 
diffcovered that eerUtn yrllowish tourmiiliaes, that 
it, tboM which are yellowish by refracted ligbc, 
transmitted only odc pencil polarized in tbe same 
planr, whra cat parallel to their axis. It has been 
much used in experiments on polarization ; but 
owIqi; to the color which it prodaees, it is of no use 
whatever in reaearohea where Ibe phenomena of 
color are to be studied. When two plates of tonr. 
malinc or agate are placed in reotonpilar poaitions. 
not a ray of light is traosuiitted through them, not 
even the Ugbt of the meridian san. 

By anng any of these pieces of spporatoSi we 
can at all times produce either a ray, or a broad 
beam of polsriied light ; but when the stmcture of 
crystallized ur organised bodies ts examined by ob- 
serring their affections under polarized light, the 
Hght transmitted through their substance requires 
to be analysed by a reflecting plate, or a doubly re< 
friiL'tiDg prism, or a pUte of tourmaline or agate 
which has tbe property of reflecting or transmitting 
one portion of the polarised, uid allowing another 
portion to be seen which was in a state of oombioa- 
tioa with the first portion. 

MECHANICAL DATA. 

A iquare foot of catt iron, 1 inch thick, wdgbi 
S8 ibf. 10-7 ox.; of malleable iron 39 Ihs. 131 oz; 
of copper 4 7 lbs. ; and of lead 59 lbs. — Other thick' 
nesaes in proportion. 

The momentum or force of a body is its matter 
nmltiplied by its velocity, and thia is the basiB of 
alt toechaata and all philovophy. Velocity is as 
tbe spnoe passed through in the same time; therefore, 
matter and space are the source of all material 
power ; and wherever power is present, there is 
some matter in some motion. 

Action or parting with motion by one body, is 
always equal to the re-action or reception of it by 
another. 

Motion, or force, is propagated in a mass in 
measurable time, and this is the cause of the re- 
solcing motloD from Impact. Tbe side atruck receives 
its motiou first, and this moves the whole body. 
If the force were communicated at once to the 
whole, no direction would be given to the resulting 
velocity. 

Universally to determine the power of a machine, 
divide tbe velocity of the action by the vetoeity of 
the power. For the actual force of the eftect, 
multiply this by the force of tbe power* and allow 
a third or fourth for friction. 

In wheel -niacliinery, to determine the number of 
revolutioiifi of the last'Oioved part for one of the 
fimt-movrd part, divide tbe product of the cogs in 
the driving wheels by the product of the cogs in 
the driven wheels. 

The tncchanicnl powers may be reduced to three ; 
but Ihey ore usually expressed as six, the lever, the 
wheel, and axle — the pulley, the inclined plane, 
the screw, and the wedge. 

In a single moveable pulley, the power gained U 
doubled. In a continued combination, the power 
is twir* the number of pulleys. I<»m 1. 

In levers, the power is reciprocally as the lengths 
on each aide the fulcrum or centre of motion. 



TTie foree neceuary to move a w 
a level rood is about ooe-twcaty-tif: : 
on a railway it it bat the l&Uth; onaaanalitls 
but the tiOIHh. 

On an inclined plane, the power g«in)^ U as titr 
length of the plane to the Length of the hB»i<. Dm 
velocity, in descending to that, i " 
dioulorly is as the height to the 
foree is the same. For a body ac^j.....^-. ;^^ •■«. 
velocity 08 in falling perpendicularly throngb Ai 
height of the plane ; and a body ac<|uirea the suae 
velocity in falling down any number of plaws, or 
down a carvOr oi perpendicularly from the 
height. 

A body, moving down an inclined plane, 
foar times as hx in two seconils as in one. 

The power of the screw is as the mrcnmfervace 
to the distance of the threads, or as 62832 to Chst 
distance. 

The power of the wedge is as tbe length of tbs 
two sides to the thickness of the back. 

The diameter of the wheel of a pulley should b( 
five times its thickness. The pin one-twelfth, sai 
one-twelfth on each side allowed for play. 

Brunei's block machine, at Portsmouth, oalUs 
the action of tsixtecn different machines ia oM 
steam engine — seven for the shell, and nine for dn 
sheave. Ten men to do the work of 110. Iti 
about 200 sorts and sizes of blocks ; i. e. 72 
of tliick blocks, 48 of thin blocks, 10 of di 
ditto, 20 sister blocks. 20 topsail ditto, 24 
ditto, 20 jack ditto. Of which Tahetica. the 
chines make 1420 blocks per day. 

A seventy-fnurgTin ship requires about 1300] 
and tliere are 200 different 6oru and siaes, 
from 4 to 2B inches iu length. Every gvo 
six blocks. 

The pendolum, for true and exact mei 
time, was a suggestion of Galileo. Gvery oecUl 
whether long or short, of the same pendolfl 
performed nearly in the same time. 

A pendulum which vibrates seconds at 
ought to be 3'J-139 Inches. 

The length of pendulums for lesa or 
times, is as tbe square of tbe dmea ; thua, 
a second, ft would be Che square of i, or 4 m 

39-139 
so that . ~ *: 9-7S425 inchea ia the U 

a half seconds pendulum at Loudon. For qn 
seconds, it would be -^ \ and for two seoonds! 
or four times. 

AtSt.TbomasN, in lat. 0*2:/, the teoonds ] 
Inm is 30*02059 ; and at the GalHpa^f. in iK. 
0^ 32'. it is 390171; ; at Manham^ ia T 37, i! 
is3U-011<»7. 

The superincumbent prestare to drfvca wMT 
into the pores of wood at great doptbs tn As sAi 
as in an hour to incresae its weight j(^, and in 
balk j^. — Scoreitiy. 

The draft of a waggon of 216 cwt. on pcvwMiil 
is 33 lbs. ; on a grovel road l471b8.; on M'AdH^ 
road 46 lbs. Horses always turn from a roatfj 
paved rood. 

The pressure of fluids is distinct from thi< 
of tlieir mass. It la as tbe height wliaii 
base. A cone ond cylinder of liquid vt 
height bus the same pressure ; but, if 
weight of the cylinder of ice would be three 
that of the cotie. The lateral pressure of the Aoi^ 
is also equal to tbe perpendicular. 



Ummv.— Pnaled bv D. Poamcti, «. Whlta Hon* Uiut. Mil* SimL— Pahllth«4 by W. Boivww. ||. L 

IfUobursh, J. MKMtiss— GU»|off, l>. Baios stid J. Baskm.— Uv«rpo«l, G. Paair. 



THE 



A.GAZINE OF SCIENCE 



.] 



anH Sf6ool of arte. 



SATURDAY. JANDARY 15. IS4t. 



lUd. 




THE AMERICAN STEAM PILE DRIVING MACHINE, 

:,— NO. XLlt, 



n.-^o 



MAGAZINE OF SCIENCE. 



TUB AMERICAN STEAM FILE DRIVING 
MACHINE. 

In ■ former number we ghre a brief occoont of tbit 
miiehine, which has been eibibited for the tut two 
nonthi at Stnilii'a Wharf, PedUr's Aerr, lAmbcth. 
The machine was imported into this country from 
the United States, by Colonel Cowdin, and some 
other parties, tiiid con4i»ts (itmplj of a locnmotife 
eng:ine, eimilnr in principle to those Qfied on our 
railway!, hiring two inclined cylindim with their 
connectini; rods working upon cmnkn attached to 
the axea of two crab engines, instead of the wheels 
of the locomotive eninne. llie two crab eogines 
perform the operation of driving the pile with a ram 
of the same weight, and in the tame mnnner as those 
generally adopted for all the lorge works in thia 
country, such as the coffer dam to the New Hnoses 
of Parliament and the bridges. Willi this machine 
t wo piles are driven at the same time. 

In Amef icA the stesm machine has been generally 
adopted for the constructfon uf railways on piles, 
for which purpose it is well adapted, for as soon 
■s the madiine has driven a pair of piles, it cuts off 
the heads to a level, or with a slight inclination, 
according to the grade required for the railway, 
and then raits arc laid upon the top either with 
cross ulcrpers or not, (is m«y be desired; the engine 
advances forward another length, and performs the 
operatioQ again : thus one engine is enabled lo 
drive two rows of piles at about five feet apart, one 
mile in a month. 

The principal object of inquiry is to see how far 
thu machine is superior to those ^in ordinary use, 
and as we just stated, in the steam machine we have 
aimply engine power applied instead of manual 
labor, for the working of two pile driving machines 
of the same magnitude and power as those in ordi- 
nary ase. For this purpose it is absolutely necessary 
to make a series of observationi, and ascertain the 
number of pdes that ran be driven in one day hy 
the steam machine, and the coit of Labor, fuel, and 
expenditure of capital, in comparison with the labor 
coniumed in driving the same number of piles by 
the ordinary machine. At present, our materials 
do not warrant us in offering any opinion, but we 
ahall hereafter attempt to obtain some information 
regarding this very important part of the inquiry. 

For the steam machine, it requires to work the 
engine and apparatus for driving two piles at one 
time, with a ram weighing 16 cwt., the follow- 
ing men: — An engine- lender . one msn for throwing 
eadi ippATttas in and out of gear, and one man to 
attend to each pile, making altogether five men for 
driving two piles. For the ordinary machine, it 
requires four men to work the orab engine for lifting 
a ram of the same weight, and one man to attend 
to the dririag of the pile, making five men for each 
pile, or ten men for two piles. With the steam 
machine the rsm is lifted four or five times in a 
minute, thereby the operation of driving the pites 
is very abort in corapariaou with the ordinary 
machine. The cost of the steam machine, with an 
engine of ten-horve power, tubular boiler, and 
appnratus, i« about 700/., and thr cost of the ordi- 
nary pile driving machine, with crab engine, is 
about 70/. 

The following is a d^cription of the .American 
etrnm pile driving machine, and the operaliona for 
whirh M is fipptirable: — 

The macliinc consists of two ptirs of leaders, 
4kmiUs to tUccwamoa hand machine, placed 6 feet 



lirom centre to centre, (the eommoti 

railway gauge,) and firmly bi»l(cd to 
horixuntAl framing, and sufiportcd by tl 
ladders. The frame is 9 feet wide to the 
the framing, and 28 feet long; it corriea 
end a locomotive boiler, 11 feet long and 
A incbea diameter, calculated to bear I20U 
square inch pressure, bnl generally worked at S| 
per square inch, and about 100 strokes per " "" 
Under the boiler Is placed the supply cistera. 
the centre of the framing, and on each aide 
boiler is a pair of inclined cylinders, &^-iach 
with solid pistons working well without 
and 14-inch stroke, which act on rigbt-al 
cranks ; and the gearing, dmms, See. descril 
the motions of the machine ; the shaft ceni 
1' a'' apart; the spar wheel has 56, and 
19 teeth; bevels 10! and 40 teeth; saw p| 
V 0" and 10^ inches diometer. The ram Uj 
raised from four to five times a minute, tbe 
being at 80 lb. per square inch. 

For river-work, the machine ia made much 
compact ; Ihe apparatus is placed on each mc 
over the boiler, so that the sUge is little mor« 1 
half the length of the machine shown in the «e 
and it is also sometimes made with an a| 
for driving one pile only, consequently reqi 
smaller power. 

The drawing is a aide elevation of the 

Taking vp tht Pile. — The ram A bcinf 
by placing the stop B under it. by veana 
amall ropes attached to the latter, and paasing 
the small pulleys C C, to within three feel uf tJ* 
atago. The dogs are made fast to the piler 
rope attached to whirb posses upwards tbrougl' 
small guide pulh^ys, and over the outer pulley 
the top ; passca downwards, sod is rniled 
the drum L lix^d on tfae abaft G, which being 
to revolve, raises the pile to its place bctwt 
leaders, and is then secured by the loose sUy^ 
iron-work U placed round it for guiding it 
diculorly. 

Driving thf Pilt. — ^The stop B bein|[ with^ 
from under the ram A, the ram ia raised by a i 
which being secured to a staple on the top j< 
paaaes down under the pulley above the ram t 
upwards over the pulley K, and a^io dowM 
to the drum L, upon which the rope is coiled ij 
drum is placed on the sliaft (3. which ia 
revolve by the spur-wheel N, workiof laj 
pinion O, on the lower shaft F, which shaft 
by Ihe action of two cranks placed on eadi< 
the abaft P ; the eraaks are set at right anf 
each other, and are worked by the com 
rods R. attached to tfae piston rods, which 
furnished with slide parallels, aa ahowa ia 
figure. The slide valvea of the nislmi are 
by the eccentric V, on the end of Ihc 
Steam La supplied to the cylinder by (he pii 
from the boiler T. The boiler is »itpplied 
water from the cistern M. by the pump, 
worked by the eccentric rod X, Ared 
spur-nave at Y, or by tlie handle at Z t 
of steam is regulated by the baDdlc. a, actfaf ^ 
valve in the steam pipe. The drum I* 
a filed and a loose cylinder ; the latter revolvii 
the frietion of the former, (fixed,) and is 
into or out of contact by the hand lever Y^ 
has a fiilrrum attached to the standard. 

The follower is furnished with a pair of 
clippers, which takes bold of a staple fUod 
ram, and carries it to the lop of the (nuae 



MAGAZINE OF SCIENCE. 



331 



lop of the tang* is pressed closer together, 
[ Ix'twi'cn the contncted chreki, tbc 

ojienft and allnvrn the rnra to fnll. 
rkini; the •pparatua, the engine-tender 
be Tftlve S, and a mun at the lever Y of 
Inf. For rsiftint^ the mm, the man turns 
itn at the valre $. which sets In motion 
tut of eftrh machine, and coils the rope 
llrams, at the ssrae time raises the ram ; 
the Utter reaches the lop of the lenders, 
t detached and desr^nds ; at the same 
c eiifine- tender turns off the steam, and 
I the lerers Y throw tbc dratn out of 
I allows the clippers and chain to Hracrnd 
bj hold of the ram ; whtn the dram is 
m into gear, the steam tumpd on, and 
lio raised, and so the operation is con- 
I the pile is driven. 

' fl i*i/e. — Chain tackle ia secured to the 
isscd over the top pullej to the dram L, 
drawn by applying the power to turn 
f the apparatus. 

^ Afpanthta consists of a circular saw, b, 
Mter, haring teeth cet 3 inches apart, 

the end of the beam K, which beam 
D apri^bt shaft for a centre, and slides 

the iron arce,- when used, the saw ii 

the proper height by the terews W ; 
Mvtog a hook in one end and fitting into 
Ibe beam's end, is used to press the saw 
work. Motion la given to the pullers 
'hich work the saw. llie 0]>ertitiou of 
Ihe end of a pile takes less than s minute. 
(ng Mofioit. — The hook being fastened 
I pile, and the rope passed over the 
tachcd to the tide of the frame to the 
Daad which it is coiled twice, and tlie 
)j a man : motion being now given to 
ilia machine progresses — this motion is 
U dotted ropfl. It should be sUted that 
la intended to be sapported upon six 
■eU, which mn on a temporary rail laid 
ftf the piles as they are driven. There 
Bode of progressing, but which Is not 
nswer lo well, vix. by means of two 
as faced with iron, and attached to the 
Ang ; these are placed sii feet apart 
k to centre, and past ander the whole 
kfl machine, and Hlide on small iron 
I to fUndardi, which are placed loose on 

ih-bob U BDSpentled to a line, rcgTilntes 
ng driven ptrpemlicularly ; and Y is a 
led to A frirtiun hnnd-break passing 
nd of the drum, which is onl^ used 
,— Ci'ciV £n ff inter' § Joumaf. 

DA AND MEZZOTINTING. 
I Hcovnt of this species of engraving, 
'Oa the continent where it was originally 
I page 2*J2. The British artiste have 
roved upon it. The first thing is to 
'-point an outline of the subject in the 
Lck we have already described. The 
I properly ctraned with whitening, lo as 
tt remove any grease. A solution of 
, as a ground. The resin is reduced into 
lOre or less fine, According to the kind 
k be represented, and pot into a bottle 
of wine. The plate is placed in any 
rio an inclined plane of about fifteen 



•rw an uclinei 



degrees ; and the composition of the spirit of wine 
and reain poured over ita stirfsce in n slow aud uni- 
form manner, taking eare to cover the face of the 
plate without having to repeat the operation ; the 
spirit of wine will run off, and be caught in the 
vessel, and what remains will aoon dissipate, leaving 
a beautiful and uniform surface of the particles of 
the resin, which will adhere firmly lo the copjMjr. 
The outline can be distinctly seen through this 
transparent groand, and tlte biting or corrosion ia 
procreded with as before directed. When Ihia is 
completed, the parts which require rounding mnst 
be done with the scraper and burnisher. 

It ma^r be easily conceived that there is some 
difficulty in prodaciog spirited touches in landscapes, 
or in giving freedom to tha foliage, by the method 
of simply stopping ap with varnish ; to obviato 
which a very ingenious plan has been devised, by 
which the touches are laid on the plate with the 
some ease as India-ink on a drawing. The finest 
quality of whiting must be mixed with a littli: 
treacle, and dilated with water. The touches are 
then made with a camel-hair pencil. The whole plato 
is then covered with a varnish of turpentine and 
asphaltum, and permitted to dry. ^Vhen the acid 
is applied, it will be found that those places which 
have been tourhed with the whiting and treacle will 
immediately break up. and expose those touches to 
the action of the HL-td, while the other parts of the 
plate will completely resist it. 

Rn^ratnng in Mczzotinto differs entirely from the 
manner above described. This method of pro. 
ducing prints, which resemble drawings in India- 
ink, is said by Evelyn, in his " History of Chalco- 
graphy," to have been discovered by Prince Rupert. 
Some account^! say that he learned the art from an 
officer nuracd Siegen, or Slchem, in the service of 
Hease-Cajsel. tt has been, for many years past, a 
very favorite way of engraving portraits and his- 
torical subjects ; of the former, the large heads of 
Pry are of superior excellence. The tools required 
for this easy and rapid moile of proceeding are, the 
grounding tool, the scraper, and the burnisher. — 
The copper-plnte should be prepared as if intended 
for the graver, and laid flat upon a table, wtih a 
piece of flannel spread under it, to prevent the plule 
from slipping; the grounding-tool ia held perpeo- 
dicularly on it, and rocked with moderate pressure 
backwards and forwards, till the teeth of the tool 
hiive equally and regularly marked the copper from 
aide to side ; the operation is afterwnrds repeated 
from end to end, and from each corner to the op- 
posite ; but it is uecesMry to observe, that the tool 
mnst never be permitted to cut twice in the sAma 
place ; by this means the surface is converted into 
a rough chaos of intersections, which, -if covered 
with ink and printed, would present o perfectly 
black impression upon the paper. Some modem 
artists have found that it is much more easy and 
expeditious to grain the plate by only bringing the 
grounding tool twice over it. This practice pro- 
duces a much more dotty and richer effect, and 
saves half tlie time besides. No outline is made 
on the copper, but the picture is divided into 
squares, and a similar number of smaller lots drawn 
on the copper with a black-lead pencil. This ia the 
most tedious part of the process. The rest, to a 
skilful artist, is much more easy than line-engruving 
or stippling. It consists in prcKsing down or rub- 
bing out the roughness of the pl.ile, by means of 
ihr burnisher and scraper, to the extent of the !□• 
tended figure, obliterating the ground for lighla, 



S3S 



MAGAZINE OF SCIENCE. 



and leaving il for shadea. Wbere a strung t>g^^ i* 
rr<| irMi, the whole (ground tserued. For a median) 
li|ht u is moderately burnished, or partially eraied. 
For tbe dre|reAt ilindni Ihe i^rouud it |pft entire. 
Care is taken to preserve the insensible gradations 
of light and shade, upon which the eBect and liar- 
moil]! of tlie piece rasentinlly depend. Engraving 
Id meuotlnco approaches iniire nearly to the efleot 
of oil painting than any other ttpecieH, from the 
•troug and broad effects of light and shadotr ivbich 
it b capable of producing. It is well calcaUted for 
the representation of obscure pieces, such as night 
scenes, &c. The principal objeccion to the mrthod 
is, that Ihe plate* wear out speedily under the press, 
and, of course^ yieJd a conipsratirely small number 
of impretiiona. iJut, since the use of steel plates 
Las been discovered, a much greater number of icn- 
prcsaions i'.an be Uken off, althougk mucb fower 
than in Line and other engrariDgi. 

STEAM AND THE STEAM ENGINE. 

f HviuiHciJ /tvm pOjif 310.J 

In our last paper upon this subject, we considered 
it necessary to give a succinct accDuut of that ex- 
traordinary mnn, the Marquis of Worrester, who is 
almost univeraally admitted to have been the real in- 
ventor of the steam engine. "Though," as I'rofe&sor 
Kobison observes, "the account he has left of it is 
not sufficient to give us any distinct notions of the 
structure and operation of his engine, yet it is exact 
as far as it goes, agreeing precisely with what we 
know of the subject." But the Professor afterwards 
adds, ** that the account is such that it could instruct 
no person who was aot sufficiently acquainted with 
the propertiea of steam, to be able to invent the 
machine himself ; his descriptions seem not so much 
intended to instruct the public ns to raise wonder, 
and his encomiums on their utility and importance 
are, to ■ degree, extravagant.'* It is, indeed, a 
matter of considerable doubt if his steam appiratiu 
was ever, in reality, in action at all ; yet mnchincs, 
which bear tlie name of the Marquis of Worceaier, 
are made, not as exact counterparts of his, but 
rather as modeb, showing how his description 
might have been brought to bear. One of these 
models is reprettentrd annexed ; it is the contrivance 
of Professor MiUington. 

The two spherical vessels A O have two pipes 
D F proceeding from tlirm, and inserted into a 
boiler G. The&e pipes have two stop-cocks ZW, 
which shnt off the communication between the 
bailer and the Teasels. Prom nmothcr part of the 
vessel proceeds two other pipes, having valves at 
SX, opening outwards, and terminating in a single 
pipe B. The spherical vessels hsve each another 
viJtc opening inwards, and a very short pipe N V, 
The pipe £ rises 40 feet, and terminate in the 
receiver U. B is a section of the 6re grate, under 
Ihe boiler E ; T the door of the fire-place; L the 
brick-work ; G the ashpit : and H the raervoir of 
water in which the vessels O A are placed, tad which 
is to be elevated into the cistern U. 

If we DOW suppose a sufficient quantity of steam 
to be generated in the boiler C from tlic water G, 
and the stop-cock Z, opened so as to allow a free 
communication between the boiler and the vessels 
in the reservoir, the steam will de&ccnd in the pijie 
D (the pipes and vessels being made or cused with 
aome material to prevent the condensation of the 
steam by the water in the reservoir,) into the vessel 
A, aod *iM expel all tha water or air which it may 
contain through the valve S, into the pip« E, which 



will deliver it in the reservoir V. The eoek X b 
iu>w to be shut, and tbe valve V, being freed from 
the pressure of the elsslic vspor, will \m f ereeJ 
inward by the gravity of the water id the reamoir, 
which will speedily All the vessel A. But when the 
cock Z is shot, tbe opposite one, W, is ofieued, sqU 
the steam from the boiler raises tlir water mhwk 
may be contained in O, up the pipe £, cloaioc la 
this operation the valve S. When tbe vcaarl O ia 
filled with steam, the rj>ck W is shut, and the waUr 
in the reservoir rushes into O, as it did into A, nd 
fills it. Tlie cock Z is now opened, and tbe steaa 
again expels the water from the veasel A : and «• 
on successively, so long as steam is produced in tbs 
boiler, and U)o cocks Z W are opened and liisk 
alternately. 



^v»*»»»"«*^ 




Mr. Mitlington remarks, that this eugiuc 
BO far with the Marquis of "Worcwler'a dc 
where he says, that " a man has but to 
cocks, and that one vessel of water being coi 
another begins to force and rrfill." Heal 
aerves. that the condensation of the steam 
and shuts the valves, and fills the vesaeli, but I 
this use of the vacuum is part of an invention 
which the Marquia has no claim, bis Lordship 
pressiy stating, that "the water i> not 
drawing or sacking it upwards.*' The " 
n^fill " in the original account would almost! 
Hupposition that these operations were goingi 
sjime moment, in the same vessel. The ai 
of pi|»es, cocks and valves is alao gratuitoui. 

Besides which, it is impossible to decide Cna 
Lord Worcester's description whether hro letftf* 
are meant, and one nceiving vtsset : or two 
and one boiier t* Oronly two\esself. like De< 
probably having each an edui: lion -pipe 
proper cocks, to produce a continuity in the 
of water ? — as in the next fi^urt?, wbere tb" 
lines rising from the vessel A would ihfn rept 
this pipe, the fire bring made under each be 
alternately. And, when mention is made of cm 
vessel of water rarefied by fire, driving up forly rtf 
cold water, ihooid not thu be understood as tlir 



MAGAZINE OF SCIENCE. 



trtion uf wmter which would be converted into 

r'l' r fn raiu the remaining portion ia 

::y feethi|i;h ? An apparatUB de- 

MOBktioo, would satisfy the deachp- 

Uian any. 

so wide a choice^ we wjU ipve the Mar- 

for an apparatu for generating the ateam 

tf^porolf boiier. K will therefore be that 

'} C( ■ pipe (liariug a stop'Cock U,) connect- 

Kbs boiler with the cold water Teasel £, from 

;ds the eductioa-pipe F ; G. a pipe and 

supply the boiler with water ; U, a aimi. 

>oock lo lopply the vessel E with cold water 

with a cistern, from which the water is 

-nia»d i I, is a stop-cock on this pipe; K, a 

preTeat the return of the water which may 

apper part of the pipe F. 

the steozn in the huiler A is sUowed to 

Iter the cold water vessel £, by turning the cock 

Jbe wsier la raised in jet through F, until the 

,£ is emptied. When this is the case, the 

^'JD ia shut, and I is opened, and the vessel E 

filled with cold water. The cock 1 is then 




IJMtj;] ^ 



• atop-oock D is opened ; and the steam 

Icr presaing fln the surface of the water 

it up ibe pipe P. Wben this is emptied 

I'eration is repeated, nnd so on sacces- 

'.hst here the condition of the altcmAte 

and shutting tvo cQcJtt is fulfilled ; also the 

and refilling of the vessels; and one vessel 

rarefied by lire would elevate double the 

of that stated by the Marquis. 

fTob* rvniinmmLj 

CAUSES OF DROWNING. 

lOTT. in bis popular ElcmentK (ff Phy*icM, 

following reasons why, iu ordinary acci> 

•9 mnny persons are drowned who mi^jht 

aared : — 1. Their believing that the body 

than water, and therefore that condiiued 

is necesi*ry to keep them swimming ; and 

[,Uiar genrrally assuming the position of a 

in which the face is downwards, and the 

has to be kept oat of water to allow of 

^''-tChiiig. Now, as a man cannot retain this posi- 

t without continued exertion, he is soon ex- 

jUd. even If a swimmer ; and if not. the un- 

/ni attempt will Kcarrely secure for him even a 

respirations. The body raised for a moment by 

jtioo above the natural level, sinks as far below 

whvn the eirrtioo ceases ; and the plunge, by 

,!f«rmc the commencement of a permanent sink. 



ing. terrifiea the nopnictiaod individual, and renden 
him an easier victim to his fate. 2. Prom s fear 
that water by entering the ears may drown, as if it 
entered hj the nose or mouth, a wasteful nrrtion 
of strength is made to prevent it; the truth beingi 
however, that it can only fill tlie outer ear, or as 
far as the membrane of the drum, nod is therefore 
of no ooDMqaenee. Every diver and swimmer hii 
his ears filled with water, and with impunity, 
'i. Persons unaccustomed to the water, and in 
danger of being drowned, generally attempt in their 
struggle to keep their hands above the surface, from 
feeling as if their bands were tied while held below ; 
but this act is most hurtful, because any part uf the 
body kept out of the water in addition to the face, 
which must be out, requires an effort to support it, 
which the individual is supposed at the time ia- 
competent to afford. 4. The not having reflected 
that when a log of wood, or a human body, is float- 
ing upright, with a small portion above the surface, 
in rough weather, ns at sea, every wave in passing 
must cover the head for a little time, but will again 
leave it projecting in the interval. The practised 
swimmer cboosei this interval for breathing. 6. Not 
knowing the importance of keeping the chest as 
full uf air as possible, the dotnE; of which has nearly 
the same effect as tying a bladder of air to the neck, 
and without other eflbrts will cause nearly the whole 
head to remain above the water. If the cheat be 
once emptied, while from the hoe being underwater 
the person cannot inhale again, the body remains 
specifically heavier than water, and wiU sink. 
.,.- -..__,_ «^ 

NEBUL/E. 
In astronomy, the name given, on account of their 
general cloudy appearance, to a very numerous clnss 
of celestial objects, being, however, for by Air the 
greater part, ieiercopiCt and only visible in telesoopet 
of considemble powprs. 

It is to Sir ^i'illiam Henohel that astronomy U 
indebted for the first examination and analysts of 
these reroarkablc ohjecta. A few of them, indeed, 
have been known since the discovery of the tele- 
scope, and one or two of them are visible to the 
naked eye : but his powerful telescopes fint dis- 
closed tbe fact of their existence in immense num- 
bers, aud in all q^iarters of the heavens, not indeed 
distributed uniformly, but, generally speaking, with 
a marked preference to a broad zone, crossing the 
milky-way nearly at right angles, and whose general 
direction is not very remote from that of the hour 
circle of hour and I2b. 

Ncbulsc are divided by Sir W. lierschel into the 
following classes : — 1st, Clusters of stars, in which 
tbe stars are clearly distinguishable ; 2d. Resolva- 
ble aebake, or loch ai» excite a suspicion that they 
consist of stars, and which any increase of the 
optical power of the tclt^scopc might be expected 
to resolve into distinct stars; 3d. Nebulee, properly 
so called, in which there is no appearsnce whatever 
of stars ; 4th. Planetary nebulm ; 5th. Stellar 
oebulie ; aud, 6th. Nebulous stars. 

C/ta/ers of Star*. — These are either globular or 
of an irregular 6gure, forming bright isolated 
patdies, which attract atteution, sa if they were 
brought together by same general csum:. The 
Pleiades is a cluster of this sort ; the naked eye can 
distinctly perceive six or seven stars in it, and may 
catch oocaaional glimpses of a great many more ; 
but the telescope shows fifty or sixty crowded 
together, in a very moderate space, and insQlaied; 
from the rest of the heavens. A luminous 




3:J4 



MAGAZINE OF SCIENXE. 



called Praaepe, or the Deehive, in the coastellfttioa 
Cancer, is refloWeil entirely into ttan by an ordi- 
xiHry telescope. In the Bword'bsndle of Penetu ii 
another auch spot, crowdrd with atari, bat not h 
easily reaolved. There are a great number of Icsa 
distinct ncbuluiia apecks Qf the same kind, which 
in nrdioarj tele»copea baTC mach the appearance of 
cornet* without tails, and have frequently been 
miataken for aach ; ti ben, however, they are ex- 
amined with instromenta of great power, such as 
redectors of 18 iocbes, 2 feet, or more in aperture, 
any auch idea is completely destroyed. They are 
then, for the most port, perceived to constat eulirely 
of itars, crowded ioK«Uier so as to occupy almost 
a definite outline, and to ma up to a bliue of light 
in the centre, where their condensation la usually 
the greatest. Blany of them are of an exactly 
roaad figure. Others, again, are of an irregular 
ftroii and less definite in their outline, to that it ii 
not easy to say where they terminate. In some of 
ihciD the st&ra are nearly all of a alze, in others 
uiremely different ; and it is no uncommon thing 
to find a very red star, much brighter than the rest, 
occupying a conspicuous situation In tlic group. 
Sir W. iierachel regarda these aa globular clusters 
in a leas adTanoed state of condensation ; conceiving 
all such groups oa approaching, by their mutual 
attraction, to their glubuliir figure, and assembling 
ihcmselves together from ail the surrounding region. 

Kesvtvattle NeiuicB are considered oa objects of 
the some nature aa the preceding ; but aa being 
either too remote, or conaisting of stars too faint to 
affect us by tbeir individual light. They are uni- 
Teraolly round or oval ; their irregularities of form 
hang extinguished by the dlatance, and only the 
general figure of the condensed part being dis* 
oemible. In telescopes of insufficient optical power, 
ail the ^reat globular clusters exhibit themselves 
tinder tbis appearance. 

NflfHJtr, ffroperfy to calUd, present a great variety 
of ap|»earaiicea. One of the most remarkable is 
in the constellation Orion ; snd its appearance is 
very different from what might bo supposed to 
arise from the aggregatiua of aninimeuse collection 
of amall stars. It is formed of Uttie flocky masses, 
like nispB of oload ; and such wisps seem to adhere 
to many small stars at its outskirts, and especially 
to one considerable star, which it envelopes with a 
nebulous alraoaphere of considerable extent and 
aingtilar figure. This nebula was discovered by 
Huygeos in 1666. who gave figures representing its 
appcaranco in his telescope. Ou compariug tbeoe 
with its present appearance, aeverol astronomers 
bare concluded that it has undergone n perceptible 
change ; but the evidence of such change is by no 
means to be relied on. I'here is a nebula in the 
cunKteilation uf Ariilrumeda visible to the naked 
eye, and ohvtn mi.^titken for a comet. Its appear* 
ance is described by Simon Msrius as that of a 
candle ahiaing through horn. Its form is a pretty 
loDg ovol, increasing by ias^osible gradations of 
bri^btneas, at first very gradually, but at lost more 
rapidly, up to a central point, whioht though very 
much bri,i;hter than tbe rest, is yet eridently not 
stellar, but only nebulous matter in o high state of 
condeDsatioD. It bos in it a few small stars ; but 
tliey ore obviously casual ; and tbe nebula itself 
offers not the slightest appearance to give ground 
for a suspicion of its consisting of stars. It la 
oaarly half a degree long, and tiftecn or twenty 
minutes broad. Like that last described, a very 
numerotu class of ncbalie are of a round or oval 



figure, increasing more or less in den»ity toirirda 
the central point. In this respect, how^^r-r rh»< 
differ extremely; in some the cnmlen> 
slight snd gradnal, in others groat an 
Tbcy also prevent great diversity of spp&afaaec. ta 
respect of deviation from the spherical form 
are only slightly elliptic, others much crtsadld ia 
length ; and in some the etteosion is so groat as la 
give the nebula the character of a long, nanoop 
spindle-shaped ray, tapering away at both cods ttl 
points. Some nehole are annular; but thcss Mt 
among the rarest objects io the heavens. Tbo vstt 
conspicuous is situaied half way between the ttan 
^ and > Lyrw, and may be seen with a telctrDprof 
moderate power. It is small, and particularlj- vsij 
defined, to as to have, in fact, much more the wp* 
pearanoe of a flat oval solid riutt than of a ncbnl*. 

Planetmy Nrbvl^ have exactly the appearsMs 
of planets, — round or slightly oval disks, in anoa 
inatancea quite aharply terminated, in others a 
hazy at tbe borders, and of a light exactly 
or only a little mottled, which, in some • 
approaches in vividness to that of aotual 
Whatever the nature of these objects may 
must be of enormous magnitude. One in Aq 
presents a diameter of 20" ; another, in Andn- 
mcda, has a visible disk of 12", perfectly deftoa4 
and round. Granting them to be equally distiBl 
from us with the stars, their real dimensions nmt 
be such as would fill, on the lowest co- 
tbc whole orbit of Uranus. Their intn 
dour mtist also be immeasurably inferior W 
the sou's ; for a circular portion of the sou 
subtending an angle of '2U", would give a light 
to 100 /«// meoM. whereas the nebulK in qu 
are hardly discernible with Oic nsked eye. 

Siellttr Nebtilft are those in which tbe condenss- 
tion of the nebulous matter towards tbe ccutrs ti 
great and sudden ; so sudden, indeed, as to preseat 
the appearance of a dull and blotted star, or a 
with a slight burr round it, Tbe Nr^oiooa 
present the beautiful and striking phcnomi 
sharp and brilliant star, surrounded by a 
circular disk or atmosphere of faiut Ught : 
casrs dying away on all sides by insensible 
tions. in others almosc suddenly terminated. A 
fine example of such a ator is 55 Andromeda 
R.A. lh43m. N. P. D. aO' 7'. 

*' The nebulse," says Sir J. Herscbel. * 
in every point of view, an inexhauatible 
speculution and conjecture. That by far tbe 
of them consist of stsrs there can be little 
and in the interminable rangtt of system upon sy 
and firmament upon firmament which we thus 
s glimpse uf, tbe imagination is bewildered oo^ 
On the other hand, if it be true, as, to any 
it seems extremely probable, that a phosp 
or aelf-luminoua matter also exists, di 
through extensive rrg^ione of space, in the 
of a oloud or fog, now assuming capricious 
like actual clouds drifted by the wind, and now 
centrating itself like a cometic atmos|ihffe 
particular stars, what, we naturally ask, iatbo 
and distinction of this nebulous matter? Is it 
sorbed by the stars in whose neighbourhood it 
fouud, to furnish, by its condensation, their 
of light and heat? or is it progressively 
trating itself, by the effect of its own grav 
masses, snd so laying thi? foundations of new 
real eystems, or insulsted stars ? It is easier to pr»* 
pound such questions than to offer aoy probabiv 
reply to Uicm." 



MAGAZINE OF SCIENCE. 



335 



TION OF SULPHURIC ETHER. 

nmuilly obUined either by duliUing a 

lulpharie ncid and aJcobol. or by latfer- 

ri graiJuftlly to dribble into the heated aad 

dilated ncid. Mr. R. PhiUipa* directions 

r process are as follows : — " Mix with 

of sulphuric acid, an equal weight of 

Kptrit. and distal aboat 10 fluid oances; 

of spirit to the residuum Ln the retort, 

about 9 fluid ounces ; or <»ntinae the 

antil the contents of the retort bcgia to 

\ product becomes considerably sulphnr- 

the two producUi, and if the mixture 

f • lif^ht and heavy fluid, separate them : 

Vh to the lighter, as loog as it appears to 

^d ; aeparaler the ether from the solntion 

and distil about nine-tenths of it, to be 

ms ttAer tuipAuricut, the specific gravity 

Doxbt to be at moAt .760." 

f ether upon a larger scale, it was found 

larts of alcohol (specific gravity .820) 

aa equal weight of aatpbohc acid (spe- 

Ity 1.8), and aubmitted to distiUatiun, 

iwmt 8 parts of impure ether (specific 

70). Seven parts of alcohol were then 

be residuum, and about 7$ paria more of 

tbtr drawn off. These products, when 

id ■ specific gravity of about .782, and 

^ed by distillation ou carbonate of po. 

krded 10^ parts of ether, of a specific 

■735. and about 3^ parts of ethereal 

ich was employed instead of an eqnal 

aloohol in the next operation. 

when carried on on a small scale, 
Kmdnoted in glass retorts with adopters 
rcoeivera ; but upon the Urge scale, a 
or alembic is most convenient. The 
itns employed at Apothecaries' Hall, 
f a leaden still, heated by means of bigh- 
m carried through it in a contorted 
e; a lube enters the upper part of tbe 
parpose of suffering alcohol gradually 
tbe acid in a way which will presently 
The atill-head is of pesrter, and is 
by about 6 feet of tin pipe, with a very 
condensmg-worm, duly cooled by a cur- 
ter; the receivers are of i^wter with 
and have a side tube to connect them 
ivering end of the worm-pipe. In con- 
is operation, too much caution cannot be 
avoiding tbe proximity of fire, and the 
• vetacls ; in alt case^ in which ether is 
with these cautions cannot be too strictly 
will be more evident when its propcrtirs 
One of the great advantages in using 
the source of heat ia, that it obviates the 
[ TiciDity of fire. 

f'i process for the production of ether, 
treferable to the former, is the following; — 
of Bolpburic acid and of alcohol (ape- 
Ity *H37j are cautiously miied in a tubu- 
rt connected with a tubulated receiver by 
■ long adopter ; the retort ta placed in a 
; and the receiver cooled by the proper 
of water. An S tube passes air-tight 
tubulature of tbe retort, the lower end 
ia drawn oat into a very smalt or almoat 
opening, and so adjusted aa to dip to 
thirds of tbe depth of the liquid in the 
t ia then opplied by the sand-bath till 
of the retort just begin to appear to 



boil ; tbe fire is then slackened or damped so aa to 
keep op a regular ehulUtioa, and as the apparatui 
is air-tight, the expansion williin is sulfered to 
escape by a siphon tube, which paues tbrongh the 
tubulatnre of Uie receiver. \Vhea about 2 pints of 
product have passed over, an equal quantity of 
alcohol is so gradually suffered to trickle into the 
retort by the S tube, as not to check ebullition, but 
to compensate for tliat whirJi distils over ; when, 
in this way, a quantity of alcohol had been added 
equal to that contained in the original mixture, tbe 
operation is gcnrrnlly Irft to itself, and as soon aa 
white vapors and drops of oil appear in the 
adopter, the fire ia withdrawn. The products of 
this distillation are usually divided into three parts ; 
tbe first is alcohol with a little ether, which first 
passes over ; the second and largest portion ia 
mixed with a sixteenth of its weight of carbonate 
of pota&sa, which abstracts water and sulphurous 
acid, and decomposes any oil of wine that may 
chance to be contained in it ; this mixtare ia ahakeo. 
and when the ether has acquired a sweet and pure 
odor, it is rectified by slow distillation from a 
water-bath till two-thirds of it original bulk have 
distilled over ; this portion Is pure ether. The 
reaidne of the reetifintion is mixed with tbe last 
portion of the original distillation, and kept for 
some days in contact with the carbonate of polasaa 
before used, and a little water and peroxide of ouo- 
ganese are added so as to get rid of tbe sulpharooe 
arid ; when this is done, the stratum of ether \» 
drawn off and rectified, hot it never equals in 
quality that of the former part of tbe process. 

It will be obacrved that, in tbia process, a lai^ 
additional quantity of alcohol is gradually added, 
and converted into ether by the original portion of 
sulphuric acid ; and by obvions oontrivaneea, the 
same thlug may be effected with the itiU and appa- 
ratus used on the large scale, 

Mitscherlich. in tbe first volume of hU Lehr^uck 
dtr Chermit, has added some important facta to 
the preceding details, and baa given a form of 
apparatus for the production of ether which well 
illuatratea it. It consists of a large flask or bolt- 
head, the mouth of which is closed with a eorlc 
having three perforations, one of which allows Iha 
insertion of the thermometer by which the tem* 
perature of the contents of the flask can be regu- 
lated ; the second admits of tbe passage of a amall 
tube terminating at its upper end in a funnel, and 
at its lower, within the flask, in a capillary opening 
which dips into the liquid ; from the third aperture 
a tube issues for the conveyance of the vapor* 
generated within the Hask into a proper condeaiei 
immersed in cold water ; the end of this tube 
within the flask is slanted off, so that liquid form- 
ing in it may drop bauk into tbe flask and not 
obstruct the free egress of the vapor. Absolut* 
alcohol ia first poured into the flask, and then sal* 
phuric acid, somewhat diluted, is graduilly added, 
care being taken to prevent the heating of the mix* 
ture above Z^iO" (120 cent.) The proportions are 
100 parts of sulphuric acid, which already cootaina 
18.5 of vrater. diluted with 20 parts of water, and 
mixed with anhydroaa alcohol, in tbe proportion of 
50 pnrta to every 100 of conoentrated acid. To 
this mixture heat ia applied, and it is kept holUng 
till the thermometer within the flask indicates 284 
(MO cent. :) two strips of paper are then pasted 
upon opposite sides of the flask to indicate exartly 
the bulk of its contenta, by shunriug the level of 
the liquid within it ; alcohol it then suffered to flow 



33G 



MAGAZINE OF SCIENCE. 



ia by the funnel-tube, the supply being lo regulated 
at to maintJiin the boiling-point at 284^. If. hftving 
set oDt with 9 ounces of ralphuric icid, 1^ ox. of 
wmler, auJ 3 ounces of alcohul in the 0mk, the 
iprri^c graTttT of each sacoes»ive 2 ounces that 
pagf oTer into the receiver attached to the condrocer 
be deteriuined. that of the fint 2 ouocrs will be 
0.7HO, that of the two following 0.788, and this 
gradually increases to 0.798, at which the density 
generally arrives by the ninth or tenth ounce, and 
then remains constant ; that being nearly the density 
of the alcohol used. 

If the precaution just stated respecting the ad- 
jostmcnt of the temperature be strictly attended to, 
any quantity of alcohol may he etherized by the 
same portion of acid, which is no further altered 
than by foreign matters which may be accidencally 
present, or by the volatilization of a minute portion 
along with the ethereal vapour. 

The liquid which passes over tlirough the con- 
densing -apparatua into the receiver, separates into 
two parts, the lighter fitratum being ether, with a 
Uttle alcohol and water ; and the heavier, water, 
with a little alcohol and ether ; and when the pro- 
cess has been carefully conducted, the weight of 
these products eiactly corresponda with that of the 
alcohol conauoied. In an rrpenment in which a 
Urge quantity of product had been obtained, it was 
found to consist of H't ether, IS alcohol, 17 water ; 
now the quantity of water which should hare been 
evolved in the production of C5 parts of ether is 
15.4 ; so that the practical is as near to the theore- 
tical reaolt as could be expected, considering the 
imposBibUity of preventing tlie loss of ether by 
evaporation, and including errnrs of erperiment. 
Careful manufacturers obtain from 100 ports of 
spirit of wine, containing 76 parts by weight uf 
raihydrouB alcohol, 60 parts of ether of the specific 
gravity 0.727 ; according to calculation, they should 
obtain as parts of ether of 0.724. With this 
diluted alcohol, the water which passes over is of 
course in greater quantity than when absolute 
alcohol is u.^d. 

The ether of commerce almost always contains 
aleohul, which materially aflecta its density; some- 
timu it also contains «'ater, which is the case with 
whut ii termed vtuhed tthtr .- and if ether has been 
long prepnred, it is often altghtly acid, and leaves a 
peculiar odour when rubbed upon the hand. In 
order to procure from it perfectly pure ether, it 
must be well shaken in a close veniwl witli about 
twice its bulk of water, and altowcd to separate 
upon its surface ; it is then poured off, and a sufH- 
(ient quantity of welUhnrnMl Hmc added to it, by 
which the water which it had acquired by the agita- 
tion ia abstracted ; the mixture of ether and lime is 
then distilled, care being takf^n toprtront all escape 
of vaponr, and to keep the condensing-recetrera 
cold, and the first third that diatils over msy be 
oonsidurcd as pure ether, fru from alcohol and 
from water. 



MEMORANDA. 
Height of Wsrres.— The highest wave which 
struck the French ship Vrnta, during her voyage, 
was 7''> metres {T.\ feet) ; the longest wave was 
met with in tlie south of New Holland, and was 
three times the length of the frigate, or 150 uetrea 
(492 feet). 



Moti(M «H Rivers, — A fall of one-tCBfh tf so 
inch per mile will prodnce a motion ii> riveit. T^w 
greatest velocity is at the lurfsce and in the sttile. 
and the least at the bottom and tides i but a tfcc 
velocity increases, the action on the sides an<! bottom 
increase also. The mean velocities are as the ins 
of the sections. 

7b Cojuntme the Smoke from a Boiler 
— Let the fresh coals be put into the furnace ui 
to the door as possible, and leave the door 0{ 
a spaco of two or three inches to allow cold 
enter, this will keep down the greater part of the 
smoke, which will be consamed ; the aanrte niiy be 
applied to manne engtne.i. Tbia method will U 
found as efficacious as any patent that has yet bna 
token out. 

Safety Vahe to Steam Boiitre. — At a Ute mert- 
ing of the Society of Arlii. the gold laU medal ma 
awarded to Mr. Robert M'Ewen, for a mercsml 
gnage wbir.h answera the double pnrT>-^«>; cf an 
dicator of steam-pressure and a ~ 
engine boilers. The novelty of th. 
aists in the employment of a mer> 
safe-vent for the steam, these Tobe-^ 
been used only as indicator? of pi 
length aufhcifut to allow the 
dangerous degree of pressorf 
other notice of the fart than 
by the eye. As the action of ^'■ 
valve depends on a purely phyrtc: 
the oppotfilion of the elastic force ' 
K'Atic pressure of mercury without a ■ 
obstruction of any kind, it alVords a fr* 
the ste-am when its preaaure (v ' '' 
responding to Xht. length to wtr 
jotited. according to the strengiL .; 

India Coal. — Dr. Hutchison, 
artillery, has drawn up a report or< 
recently discovered in the vicinity 
which it appears that this eoal i> 
lying at no great depth beneath the surfteCft 
abafls may be sunk without diffiettl^' 
ronveyanrc there seems to he every HAWij^- 
river being adjncent, and a land-catrioge of 
mile only being required. It i» not il«tffi 
the quality of the coal has been te5t^d hf 
roent, but we presume it to be the sanu if ' 
l>r. Heifer spoke so highly in his CtJtui 
Steamers will begin to ply between the 
ports in the bay of Bengal : ' ' 
coal dep&ts between the Prei<ii 
be more plentifully supplied, ;tj. . 
The effect these circumstances will > 
destinies of India can acarqely be r^[ 
India Magasine. 

Mereutaneum. — It b atatc<l that th? > 
government have rpsolved upon un i 
new excavations at Hercutaneum ai>' 
hood, and it is added that they w 
tensive acale. Nrgociations have con 
with this view for the purchase of 
on the spot ; and so soon as tlieiv 
been completed, the works will be r> 
commission of antiquaries and arcbitC4.>u is (o ^ 
appointed by the Miniater of the Interior and tfcf 
Royal Academy of Science* to preside over tb* 
operations of the workmen ; and no doubt dis* 
ooverica will be made to add largrt< 
knowledge of this interesting ruim 
manners and customs of ita former i 



LoKDOM— Pnniwl by D. Fsavcii, t, Wbl» Hona Lioa. Mtls Eod— Publt*>i»<l by W. BairraiJi. K. Palvnwiiar lt*« 
Cvinnualcatloiu, (which arc aiuwereU Monthly,) xa tw addrf^ud to lb« Eihtur.at 27, Coiiag* Grov*. Mila Sad H«s^ 



THE 



;agazine of science, 



^nd Retool of 'Sixte. 




SNOW AND ITS CRYSTALLIZATION. 



,— wo, Xtlll. 



3S8 



MAGAZINE OF SCIENCK. 



SNOW AND ITS CRYSTALUZATION. 

Snow ii fornicJ in the alr^ wbco the temp«ntture 
of the atmosjihere linki belav tbr freexin^ poiot of 
wmtcr. The particln of moiiture tbu frozen form 
flakei, haTiDg great direniitiet of deosity, and du- 
playinf innumerable Tirietiri of the moit beautiful 
Tonat, Snow-flskei, ezatnined by t microacopei 
■ppeiir to be re^lnr crjitaU ; snd Scorcchy, who 
hu fibred ninety-sii Tarieties in his " Arctic 
RegioDi/' arrangei them uaderfive foraifl, lamellar, 
•piculir, pyramidal, tkc. Like ice, and other cry». 
tiiMized bodiea, inov would be transparent were it 
not that the Air which it conUini rendetH it opaque. 
The rei^lar cryatab are faood only when the air i« 
c&lm, and the eold intense, and do not often oocar, 
therefore, in temperate re^ona. Sdow hai been 
•c«D la the polar regitms of red. oraii^ and salmon 
color. This ocoon both oq the fixed and floatloK 
Ice, ami appears, in some caies, to result from 
Tcgrtable. aod in others from animsl matter, aua- 
pcnded in the aoa, and deposited upon the ice 
around. Snow tiorms sometimes present a lami* 
uoui appearance, oovering ati objects with a sheet of 
Are, The electricity of snow is generally poiitive, 
Snow-water has been found, by chemical snaJyaii, 
•o coutaiu more oiy^n than rmiu or river water — 
A fart which accounts for Ua superior activity in 
eiuiing iron to rust* &c. Snow answen many 
T«tuable purposes in the economy of oatore. Ac- 
£uiniiUkted opon high regioni. it serves to feed, by 
iU gradual melting, strvsuM of running water, which 
a sudden increase of water in the form of min 
would eoDTert into destructive torrents or standing 
pooli, and, in many couutriej, tempers the buruiiiK; 
heats of snmmer, by cooling the breezes wbirh paitt 
over it. In severer climates, on the cootrery, it 
srrvn as a defence against the rigooi-a of winter, by 
the protection which it affords to vegetation agmintt 
Ihefmst, and tJie shelter which it gives to animiils, 
who bary themselves under the mow. Even in 
more temperate climates, vegetation suflTers from an 
open winter ; and it has been found thst Alpine 
|tlitnt9 perulied in the mild winter of England, from 
wane of their usual inowy covering. 

Of the form of the flakes of snow, Captain 
Seoresby, in his '* Dc&criptton of the Arctic Re* 
^flone,*' thos observes : — "Tlie extreme besnty aod 
#ndlfl«a variety of the microscopic objects per- 
ceived in the animal and vegetable kingdoms, are 
perhap* fully et}UAUfd, If not lurpsnted, in both 
particulars of beauty and variety, by the crystals of 
•now. The principal configurations are the stelli- 
Ibm and hexagonal, thongh almost every variety 
«f ihipe, of which the generating angle of 60^ snd 
120** are lu&reptible, may, in the course of a few 
yeara' obserwJion, be discovered. " We have 
flgnred aome m the crysuls, of beautiful form, ob- 
Mrved by Captain Sooresby ; many of the amaUer 
«f them, and others equally symmetrical, we msy 
obicrTe in this country oecasionslly. though the 
majority have not been witsessed here except at rare 
intervajj, when the cold is intense, and the snow 
lUls in small flakes. 

The MntMP'tiue, or plane of perpetual snow, is the 
elevation at which moantams are covered with per- 
petual mow. The progressive diminution of tem- 
peratnre, as we ascend through the air, must finally 
•onduet ai to a region of perpetual snow, the eleva- 
tion of which is, of coarse, very diSerent in dif- 
femt Islitudea. On the northern side of the 
Himslaja mounCaios, it is about 17,000 feeti on 



turiM of lbs 
on ^^^^1 

SDOW l^^^l 

iwbicnR 



Chimboraxo, 15.802 feet. Humboldt fixes the alU- 
tude of perpetaal snows, under ili*" rcu^im-. mt 
1j,748 feet. Towards the polo, ir 
On the Alps, under 46' north latic. < ^on£ 

8860 feet. On the Pyrenees, it ti titled Uy ilom* 
boldt at UOO toises, or about H860 feet. As we 
recede from the equator towards the north or soath, 
it sinks more rapidly, sod, at the North cape» 1b 
latitude 71^ it is estimated at only 366 toiftCS Or 
about 2440 feet. In Mexico, Humboldt, from the 
whole of his observations, made in 19' north lati- 
tude, places the elevation of the snow-line at 15.02S 
feet, or, at the lowest estimate, 14,70^ feet, ^ron 
the Utitiidc of 13" to about 31.1° we are not sc- 
quaiuted with the altitude of a eiogle snowy peak. 
Too little is known of the range of rocVy moantains 
to enable Uii to stmtt: with sccunicj their Inwr^t pUnc 
of perpetual snow. In fart, besides the rooaunt 
data of tlic latitude and elevation, the position of 
the snow -line dejiends M much upon rarUbte 
causes, inch as the form uf thr summita, the oata 
paratire altitude and other phyairjtl firotarM of lbs 
surrounding oo«atry. the psriinular exposure 
raounlauu, Sec, that no general role i 
for determiniag the limits of perpetual 
given latitude* at least, with oor prow B t 
perfect infonnstioa. Even the few facta whidf 
yet been ooUeded on this subject may stand in aol 
of the corrections of mors Bccorats meaaurvvMiV 
of hcigfau. and, in additiOQ to this, Iba lf^§0 
t>erpetual snow dors not, by any means. adMEn 
constant ulcvatioo in the same latUui' '■'.*'■" Tiw 
with the vicissitudes of the eeoaot rtsf 

the heats of gammer, and tlnklDg i^ .... .->ii if 
winter ; changing also from one summer to s.u«tkv. 
acoofding to the prevailinf tem^iermture of Ibe jht. 



STRATIFIED NON-FOSSlLrFEROUS Oft 

PRIMARY ROCKS. 

Tub primary strata are, gneiss, mioa Bchtat, htfV- 

blende schist, chlorite schist, taJeose MfaUt. i^aa^ 

rock, primary limestone, and orfirillAceoaa schlsL 

Caettt.^Gnetaa rosy be nllid iluty granite. It 
ii composed of the same iogrt-Jients aj that roA» 
via. quartx, felspar. mtcH, and hornblende united K 
rarioas proportions, with the occaaioiial abaeaca af 
one or other of them, and the prcaeoee of a Ivw 
other minerals. The diatmctive oharact4sr of giaiW 
eonsists in some of its component miacnU, gaee- 
rally the mica and horobleade, bein^ arramvd 
parallel to the stratification, so aa tu imimit %o tte 
rock a foliated appearanor, or to k ^^^M* 

character, sometimes so perfect n-^ ■ ' 'm 

being cleaved for economical puri dte- 

raoter becomes less perfect when >4 ta 

contact with granite, or tmversed by Trim i?i i^tf^ 
I at the point of contact, disappears etitlrciy, vttCt 
the twu rucks cannot, at their juix-non hi: 
gnished from one another. Fn> 
passes by the disappearance of I' 
achiat ; by the prevalence of quarts U»W 
rock, aod of faorahIendi> into harnblestdfl sehuL 
The itrstiliostion of gneisa is Irregular and een- 
torted, the dimensions of the stiata varUUs.— 
Where the rock oeears iu large masaes, they 
thick ; when they alternate frequently with oi ' 
they are thin. When they are not separated 
sueh alternations, the distinction between the sevwil 
beds is formed by a change in the proportlcaa 
the ingredients. Gneiss is, in many countries, 
moit tbundaat of the primiry itnca, occunisg B 



MAGAZINE OF SCIENCE. 



259 



krge mum, wfatnh occupy exteasive districts, and 
fern lofty moanlains. irithoot anj other slterniliDg 
rock. In inch cates it reposes upon granite. anJ 
Is niccectlfd by the other pritoary Ktrata, bat in 
■ome mrs succeeds one or other of these, lite scries 
lltcmaling in Urge masses. 

l^£rv are other instances In which a large seriet 
of ttmii. consisting principallj of gneiis, contain 
altcraating strata of other rocks in inferior propor- 
tions. The const rommoa of these is bornbleade 
tchiit ; micm schist and quartz rock arc next in 
abanditnt^^ ; argiUaceous schist is more rare. Strata 
of gneivs are often invaded by veias of grsntte, 
which are not always traosTene to the stratification 
bot somettBiea ran parsMel with it, assuming for 
lliort ipacea the stratified appearance of gneiss, 
«Dd, when of large dtmensioos, arc liable, without 
va7 careful obaerratton, to be mistaken for stratified 
gnaite. 

Tbo British localities for this rock are the Western 
Iil««nd north.wcst Highlands of Scotland. 

M"-" Vr.\,.f — Mica schist is a confusedly cry«- 
lal-i ij of quartz and mica, united in dif- 

fe'fi 'tons. It has a foUsted or laminar 

•rxtuir, and is more or leu fissile according to the 
proportion and mode of disposition in which the 
mica enters into its composition. It Is sometimes 
ps{>able of being separated into coarse alatea ; 
■Mnetimes the laminar fractare is very im^ular 
^■B Imperfect. There are cases in which it ap- 
P^^rJkei a grannlar teiture ; but when the quartx 
wc«r« the most grannlar appearance, it is always 
■ftitvd bj a crystalline cement of that mineral, 

ll«dj cf mica achist are sometimes affected by 
Uffo contortions, bat there are many cases in which, 
wboo the contortions are minute and intricate, they 
MOV) only to inroke the Uminx without extending 
to tlia bed itaelf. 

Tbe stratification of mica schist, when occnrring, 
ii U fivqueotty the cose, in large masaes, occupying 
mot tracts of country, is very difficult of detection. 
whefi the beds are not separated by alternating 
foek«, they are distinguiahable, like those of gneiss, 
"hf rbonges in the proportions of their component 
IMffla. By the admission of felspar it graduates 
tnto pidss ; and by the preponderance of the quartz, 
bito qMarta rock, with which it occurs extensively 
Uaociated. The color of the different varietiea of 
mica schiit depends upon the quantity of mica 
wUch iLey contain, whick Tsriea in hue from white 
to black, the quartz being almost invariably color- 
hiM, The pnrvailing color of the rock is therefore 

Ftj, eJU'cpt when passing iuto chlorite schist, when 
baiKJines preen. 

tCica srfii^' differs from gneiss in not being tra- 

Mri*^(l ao Oiuch by veins of granite. These only 

it wheti in contact with the granite, the 

ng small, extending only a short distance 

malt, and their origin being easily traced ; 

••ubjuct to be much penetrated by veins of 

'^uATL/.. (lutli transverse and parallel to the laminc 

of atritiriciition, and when these are contorted, the 

T*' ■' ' '"rled olfo, 

^' like gneiss, forms extensive tracts of 

i ity mountains, but it also occurs in 
of a few feet io thickness, assodaCed and 
latiog with gneiss and quartz rock. 

British localities are the Scotch llighLoods 

the north-west of Ireland. 

UoriU Schut. — The csaontial ingredients of 

rocV are chlorite and quarts, occasionaUy mixed 

f<'1»par and hornblcode. It may be dtatin- 



gnished from micm schist by its green color and 
saponaceous feel. Its moat extensive association is 
with mica schist, iuto which it pssses in so eeobibte 
a manner, by the gradual mixture of the two 
minerals with quartz, that it is often difficult to 
decide which name to ai&ign to the rock. It lo 
under such oircumslancea that it forms massea of 
the greatest extent. It likewise occurs largely 
associated with argillaceous schist, into which it 
poMea by a transition more or leu perfect. It 
alternates io imaller strata with gneiss, and, by the 
addition of felspar, graduates into some of the 
chlorite varieties of that rock. 

Chlorite schist^ under a great roriety of arpcetj, 
occupies • large portion of the lale of Anglesco, 
and a small patch of it is found at the aouth-weot 
extremity of Caernarvonshire. 

Talcote Slate. — This rock is composed of talc 
alone, or of talc and quartz. It resemblea the two 
preceding rocks, but is distinguished from them by 
the peculiar characters of the talc, and by its oolora, 
which ore lead-grey, wldte, and obscure green. It 
occurs only in beds of very limited thickness and 
persistency, imbedded in gneiss, mica schist, and 
chlorite schist, and in a few rare instances, in 
argilhiccous schist, iuto oU of which it gradually 
passes, 

Hornbltnda ^oAi'j^— Under this term Dr. M'Col- 
loch proposed to include all those compounds pre- 
viouoly knowD by the names of honibleado rock. 
primitive greenstone, and greenitoue-slatc, whether 
possessing a schistose structure or not, which arc 
clearly contemporaneous with the strata among which 
they occur. Its ingredients are hornblende and 
felspar, but the hornblende sometimes prevails ^ the 
ezolusioD of ill other mineraU. It occurs alternating 
with gneiss. It is rarely met with in large masses 
•o OS to form extensive tracts, without the alternation 
of other rocks. It is most frequently associated 
with gneias, and less commonly with mica schist. 
When associated with orgUlaceoos schist, it is occa- 
sionally observed to pass insensibly into that rock. 

CTq bt cmUinmd.J 

ANATOMY OF FISH. 
Sytrffmafic Ditition <if Ctttier. — Fishes are 
divided hy Bsron Cuvier into two series :— 1. That 
of ordinary fishes, or, as they hare been named by 
Mr. Jeiiyns, Owei, distinguished by having the 
skeleton bony, the osseous matter being diipoeed 
in fibres; the sutures of the crauium distinct; 
maxillnry and intermaxillary bones, either one or 
both present. 2. That of the CartUaginci, or 
Chwidropitryyii, distinguished by having tlie skele- 
ton cartilaginous ; the bones destitute of fibres ; 
sutures of the cranium indistinct ; maxillary or in- 
termaxillary bones, either wanting or rudimentary, 
their phicc being supplied by the palatine or vomer. 
We should nsturDlly conclude, from ubacrviug the 
great diversity in the general form of fishes^ that 
the structure of their skeleton must be equally 
various. They agree together, however, on the 
whole, in having a spine, which extends from the 
cranium to the tail-fin; and iu having tite other 
fins, particularly those of thorax and abdomen, 
srticaUted with peculiar bones destined to that 
purpose. They have, in general, many more booea 
unconnected with tlie rest of the akclctoo than the 
animals of the preceding classes. The cranium 
in several cartihiginoua fishes (in the skate for in- 
stance) hat a very simple atructure, cojuiiting 



-^ -■- -^ 



MAGAZiN£ OF SCIENCE. 



diicQj of one large piece. In the boa^ fiihcs, on 
the contrarf , lu componeni pftrts are very numeroun. 
imounting lo etghcj in the bead of the pn-ch. Must 
of the Utlrr have a more or lesa rooreable under -jaw, 

The Linnaan Syttem qf Ichthyology. — Pishei 
fonD the fourtli cUa» of animaU in the Linnocan 
ijritem, and are divided into iix orderi : — Ordera 
I, 2, 3. 4, are founded on the nature and «ttuation 
of tbe_^n«, and atao on the exiitence of Ifonj/ ray» 
in the gilla ; onlcrfl S and G are foanded on a con- 
lideration of Che nature of the giiU and their ap- 
pendages. 

The fini are named according to their litaatioii, 
t». A, pectoral fin ; B, ventral fin ; C C, anal 6n ; 
D, caudal fin, or tail ; E E E, doraal, or back fin ; 
F, booy gill-coTera ; 0, lateral, or ahJe line. The 




rentril fini are held to be analogooa to the feet of 
quadru)>eds, and thus the fint order, or apodat, 
embraces such tiihes as want the ventral fins ; order 
3) or jugular, includea those with ventral fins placed 
before the pectoral ; order 3, or thoracic, includea 
inch as have the Tcntral Una tmnediatelf under the 
pectoral; order 4, or abdominal, compnaes those 
which have the rentral fins behind or beyond the 
pectoral ; orders 5 and 6 comprehend the car- 
tilaginous diTision, and are fouoded on the nature 
of the gills and their appendages. 

The LinnEan genera are derived from tlte litoa* 
tion of the fins, the shape of the bodj, the covering, 
figure, structure, and parts of the bead, with the 
gills and their appendages. The Linn«esa apecific 
character is taken from the cirri, jaws, finV spines, 
lateral line, digitated appendages, tail, and color. 

Anatomy and Phytiotogy of Fi$ht$. — The anato- 
mical examination of fiihes forms an interesting 
branch of their natural history. An extended 
philosophical acquaintance with the human frame 
Bccessarily requirfji the aid* of human anatomy, 
nor oan a similar knowledge of the animals around 
Its be fully acquired but through the means of com- 
parative anatomy. It is thus tliat our Tiewi of 
organisation, and its ultimate application to the 
phenomena of life, become generalised and yet 
correct. It ia thus that the caniea of many ap- 
parent anomalies in the habits and manners of 
animals are developed ; and it is by these means 
only that an arrangement of them into congenerous 
groups can he satisfactorily made. The systems of 
olassifi cation already noticed, and the characters 
which their authors have seized on for their forma- 
tion, snflSciently show that something more was 
necessary than what had hitherto been done. 

The osteology nr bony itructure of fishes ts par- 
ticularly renurkabte from the circumstance already 
noticed, that in some of them the fabric is built on 
n bony, and in others on a cartiloginoas base. This 
difTerence of structure is very important to the 
naturalist, as on it the two great primary divisiona 
of fishes into bony and cartilaginons are formed. 

A general idea of the plan of the fish bones may 
be gained from the skeleton of the carp ; A, the 
occipital bone ; B, the parietal ; C, frontnl ; D, 
nasal ; £, superior maxillarr, or upper jaw-bone, 
which is moveablp ; F, inferior maxillary, or lower 
jtw ; G, 01 quadratum, a bone peculiar to fishes. 



componnded of the branch of the lowi 
the temporal bones; H, operculum, or 
1. radii of the hranchiostegoos membrane,] 
the genera are characterised ; i, doraal- 
kind of humems, or arm bone, to which t! 
fin or foreann is attached ; L, an imperfc 
M. thoracic fin ; N, lingual bone : O O, 
P, extension of the last caudal vertebra 
tarhment of the caudal or Uil-fin ; Q. 
tail-fin ; R. the ribs ; S, anal or feat-fin ; 
or cavity for lodging the eye. 



It moat not, bowesw, be supposed that bi 
one fish can be with propriety taken aa a < 
type of the whole. The general aaaemblags c 
oasooua fabric ia altogether more compli< 
that of most other animals. They varf J 
and proportion very greatly in different sj 
in point of number there is hardly ai 
among them, there being three times 
one fish as in another ; and thia ia parti 
case with the minute bones. Even (n 
of fishes called osseous, the earthy part of I 
is smaller than in other animals, thns 
them rather »e mi cartilaginous than firm 
cm the other hand, in the cartilaginoae 
cartilages are fortified by walls of 
braoe ; so that both divisions are 80i 
proximated in structure, notwithstandini 
tinctiveness of their appellations. 

The rartnagiaous skeleton ia re 
exemplify by any individual figure, 
birger flat fish, as the skate, may bate 
ttlaglnous fabric exemplified ere they fall 
but in (he lesser cartilaginous fiabes it 
easy matter to represent them. Tbcrv 
bones, ao called ; thoracic cartilagea, orj 
rertebral colamn extended into caudal 
tail. There are also pelvic cartilagca, oi 
which the anal fms are articulated. Coat 
are apparent, and surrounded by the 
which in these flat fish appear like a< 
the sides. 

The bones of the bead of fishea 
with sktn only, give to this part a rery 
line ; and in most of them the bead ia li 
portion to the body, nnd is as diversified U 
as in the number of bones that enter into M 
position. For, while the perch ha* eighty b 
its head, and some other fishes have man 
others have not half the number. In all th« 
by ossification, as age advances. The sknl 
ticulated with the neck by a single tuberek 
occiput in some fishes, and in others by m 
two condyles ; but in all it ia so joined ts li 
of tittle motion, which wonld have bean 
venient, and as they receive their food horis 
it would also have been anneceaauy. 

The teeth of fishes are not in general OO' 
with the skeleton, and as by far the greatef 
do not masticate their food, their teeth are tu 
or book-like; and are aUo variottslj placM 
some on the tongue^ in others on the pj 



I on the palnCa^ 



MAGAZINE OF fcCIiuNCE. 



id rv^a on the cartiUginovR archra of the EtUit. 

)j te«sctft of these auomaioiu teeth they hold fut 

prey, aod wheo it U too tu-fe fur perfect de- 

itSlion, they art enabled Ihiu to retain it until 

vtotiMchic portion ii dluolred. Such fishet as 

kare ik> tnrth within the mouth, nre calletl leathern- 

momthtd: such arc the carp, storgeon, Stc. In the 

ptite, on the contrarj. the teeth cover the mouth 

lltfoat rnont extennT(!ly. 

Tbe vertebnd oolumn is extremely nried in the 

iber of it* piecei, which, howerer, ar« dcter- 

tnate in nearly allied ip<N:iea. Artcdi was induced 

srize on them, as characters to diBtingui§b the 

i and the vslue of thii anatomical fact is 

prored in the investi^tiona of Mr. YtrreU, 

considers himself Uiereby enabled to dptermlne 

tbe diminQtive fish whitebait is not the yonng 

the shad {Clupea Aioia), as hittirrto contidered 

naturalists, the number of vertebrte in the shad 

inrari&bly fifiy-five, whereas in the whitebait 

ia uniformly ftfty-iiz. The vertebral column is 

[lometiiuef angular, often cylindrical, and occasion- 

ly o(uu presied . 

Tbe riba of fishes are very diversified, bcini; 

bi some, fbrlted in others, and in s third 

altogether wanting. With regard to shape, 

e comprerfcd in the carp, round in the cod, 

limped in the herring. Within the area 

I, the steniam or breast bone, thescapulR 

Ider bUdes, and the claviclrs or collar bones. 

Thus, amidst diversities of chsracter the 

atrBi>nnDar7, there is exhibited chroagbout 

natnre a relative unity uf design. In flat 

vant of ribs is compeoMited by tbe extreme 

•f the transverse processes. Two pelvic 

exist, which defend the abdominal viscera. 



ARTIFICIAL CONGELATIONS. 

very singular phenomenoo, and highly 
[admiration, that a cold far exceeding that 
•m be produced even in the middle of 
S md what sddH to the singularity is, that 
Inctton of cold docs not take place unless 
ients employed become liquid. Some- 
by re-actiug on each other they produce 
eferveacence. 
ike irstcr cooled only to the temperature of 
that ia to ssy, to 54 degrees of Fahr.'a 
lomctcr. und for every pint throw into it sbont 
Iverised sal ammoniac ; this water 
■f acquire a considerable degree of 
.axkd c\La equal to that of congelation. If a 
then containing water be put into the 
this mixture, the water in the former 
entirely or in part. If it freeses 
part, mske a mixture iu auother vessel, 
3 ihc firttf and immerse in it the half-frozen 
by tlirve means it will be entirely congealed, 
employ thia water half>froxen, or at least 
coolfd in the interior vessel, snd throw into 
-, the cold produced will be much 
'>Ie: a cold indeed several degrees 
iBflt 'ji tee will speedily be tbe result. If 
be made in a flat vessel on a table, 
IHfcle water placed between them, tbe ice 
below will make the vessel adhere to the 
Tbe sulution of the salt must be accelerated 
as possible, by stirring the mixture with s 
iot the speedier the lolution, the greater will 
cold. 
1. PolvwUc ice, and for one part of it oiix two 



parts of marine salt ; stir well the mixture, and a 
cold eqnal to that of the severest winter will be 
produced in the middle of the mass. By thrse means 
Reaumur was able to prodnce a cold 13 degrees 
below congelstioD. Saltpetre, employed in tbe 
same quantity, will produce a cold only 'I or 4 de- 
grees below freexing. It is a mistake theiefore, as 
Reaoronr observes, to imagine that saltpetre produces 
a greater effect than marine salt. Saltpetre is em- 
ployed only becsttse it is cheajjer; and besides, 
when artificial^coM is applied to domestic purposest 
it 18 not nrcfssary that it should be considerable. 
Instead of saltpetre, AUcaot soda, or the ashes of 
green wood, which cuutainon equivalent salt, might 
he employed ; the^same elfcct would he obtained, 
and at a much less expenae. 

III. A cold much grester, however, than any of 
the preceding, may be produced in the following 
manner : — Take snow and well concentrated spirit 
of nitre, both cooled to the degree of ice ; pour the 
spirit of nitre on the snow, and a cold 1 / degrt 
below that of congrlation will be immediately 
cited. If you areidesirnufl of producing a cold s( 
more'coDsiderabte, surround the snow and spirit 
nitre with ice and marine salt ; which will prodi 
a cold 12 or 13 degrees below scro ; if you the 
employ the snow and spirit of nitre cooled in 
manner, a cold equal to 24 degrrea below zero wiU 
he the result. This cold is much greater thsn that 
produced by Fahrenheit ; for it^did not exceed H 
degrees of his thermometer below zero, which 
amounts to 17^ degrees of Reaumur, below the 
same term. But this is nothing in comparison of 
what the philosophers of PeCersbargU performed, 
towards the end of the year 1769. .\ssistcd by a 
cold of 30 degrees and more, they cooled snnw and 
spirit of nitre below that temperature, snd by these 
means obtained a degree of cold which, reduced to 
the scale of Reaumur's thermometer, waa more 
than 170 degrees* below xero. It is well known 
that at thia term mercury freezes. 

IV. There is still another method of prodndng 
a cold superior to that even which is necessary to 
freexe water. It is founded on a very singular pro- 
perty of evaporable fluids. Immerse the bulb of a 
thermometer In one of tbeae Quids, such as well 
dephlegmated spirit of wine, and then swing it 
backwards and forwards in the air, to excite a cur- 
rent like that of tbe wind, which promotes tbe 
evaporation of tbe fluid ; you will soon see the 
thermometer fall : by employing ether, the most 
evaporable of all liquors, you may even make the 
thermometer fall to 8 or 10 degrees below zero. 

Very curious things might be said In regard to 
this property of evaporation ; but to enlarge fnrtbcr 
on the subject would lead us too far. We shall 
therefore only observe, that this method of cooling 
liquors is not unknown in the eaat. Travellers, 
who are desirous of drinking cool liquor, put tbdr 
water into jars made of porous earthenware, which 
suffers the moisture to ooxe through It. These 
vessels are suspended on the sides of a camel, in 
such a manner as to be in continual motion, which 
answers the same purpose as if they were oxposo^ 
to a gentle wind, and which causes the moisture |H 
evaporate. By these means the remaining liqaor IH 
so much cooled, aa to approach the degree of con- 



gelation. 



fTobc continued. J 



• To redora th* riafp^Pi of Reaumor to 
imluply by X|. ami add St 




^ 



942 



MAGAZINE or SCIENCE. 



POWER OF STEAM ENGINES. 
Iv speaking of the power or force which an rnflitfl 
exerts, it if oecetMrjr to hivr ttotne mruare of force 
or itandcrd of refereocc. That used in this coanlry 
is a horte-ptnrer, a forre eqa&l to that which the 
average »trrri;th of a hone was believed capable of 
eiertiog, Tlijt hai bcea estimated at 33. QUO avoir- 
dupois ponnds weight, raised one foot high in ■ 
minute. There have hern dtfTcrent estimates as to 
the reol power of horses, and it is now considered 
that, takiitfc the most advantageous rale for uviny 
horte*pawcr, tbe medium power of that animal ia 
equal to aboat 22,000 lbs. raised one foot high per 
minute. However, the other, 33,000 lbs., is tJikea 
u the standard, and is what ia meant when a horse- 
power is spoken of. In comparing ihn power of a 
Steam-en^ne with that of horsea applied to do the 
tame work, it roust be remembered that the engine 
faorsc-power is 33,000 lbs. raised one foot per 
minute, the rcAl horsc-powcr onlj 22,000 lbs. ; and 
that the engine will work nnccnsingljr for twenty- 
foar hours, while the horse works at that rate only 
eifbt hours. The engine works /Aree times as Ion; 
as the horse — hence, to do the same work in a day 
aa an eni^ne of one-horse power, 4.5 borsrs would be 
required— (33,000 k 3^99,000 .—99,000 + 22.000 
«4.5). llie power of a man may be estimated at 
l-&th of the real power of a horae, or, 4,400 Iba. 
raised one foot per minute. 

The following table from Tredgold, will convey 
some tdra of the power procured ftom ateam in 
Watt's double-acting engine : — 

Ui til* fnrct of Um %teBB in Utt Mtor to IMO 

The tollowinf dcrturtiocM aaii b* Buda v— 

r«rpa impelUng ibt Maam teio Iba eyltadar OflT 

C«ottn| In the cyliiKler » .tl« 

Friction uf plitoo. and Ion .IS9 

Force Unpiltiag tba ttaaro thrtmib Iba paissfo* .091 
VoTcf to worii valvB*. tniM- lujicUoo water, > ^^ 

and ovarcome frlehon nf uii J ■" * 

l^n from tlaatn cut off bcfnrc cod nf itrokt 100 

Forct rvqstrvd to work di« uir-pump OSO 

932 

Tbm, bbout 4-lOths are lost from friction, work- 
ing of the pomps, Stc. The preMure in the boiler 
may generally be estimated at that of a column of 
Ihirry-flve inches of mercury. Tbt stram in the 
boile^r is always kept a little stronger than the air — 
2| to 4 lbs. on square loch, or, about & inchea 
colnmn of mercury. 

If this be multiplied by .632, the proportion of 
the above force which reaiatns after making the 
iieersBary deductinns. as per the abore table, it gives 
22.12 inches, as the force of the ateam on the pis- 
ton represenlcd in inches of a column of mercury : 
i.e., 10.85 pounds to tbe square inch. But (be 
tnicondenaed vapor in tlie cjlinder reaiits this force. 
It also must be deducted from the above. If the 
temperature in the condenser be 120", this vspor 
will hove a force of about 3.7 inchra of mercury, 
or, 1. HI lbs. to the square inch; 3-7 inchea de- 
ducted from 22.12 inchcj, gives 1H.42 iuobes of 
mercury — or, l.Bl lbs. dcdurled from in. 83 lbs. 
gives 9.02 lbs. per equare inch, as the effective 
presHre on the piston. Calculated in circular 
Inches, u is sometimes done, we have 7-1 lbs. to 
the inch. 

The foUowing eitract from the author above 
quoted, will show the metliod of eompatiog tbe 
power of an engine, the above data betug assumed. 



*' /Ztf/e.— Multiply tbe mean effective p i iMW I B «a 
the plicon, by the >qQV« of Ita diameter lo todhiau 
and that product by the velocity, in feet per minute; 
the resole vrill be, tbe etTrcttve power in potm^ 
raised one foot high per minute. 

" To find the horses* power, divide the rsnilif 
33,000. Example. Tbe diameter of a cylinder af 
a duuble eogiue being twenty-four inchcji, th^ length 
of the stroke five feet,* the number of atrokea p«r 
minute, 21^, and the force of the steam in the 
boiler, thirty -five inches of mercury, or five indwa 
above th« preamre of the atmosphere — rcqniredi Iti 
power, 

"The velocity is 2 X 5x 211 = 215 feet per min-.t' 
and the mean effective pressure on the piston ••: 
be 7.1 lbs. per circular inch ; therefore, 7 ' 
(the square of the piston's diameter, or '■' 
»879,264 lbs. rained one foot hi($h per minu:. , «, 
879.264 
33,000 
26.64 horses' power. The nominal power of I' 
engine would be only twenty horses' powr, ' 
Boulton and Watt's mode of caUmUtion 
will be foond that the nominal and real pOv> 
agree, when the »tcam acta expanaively. * 
engine would require for ateam, half a cu^ 
water per minutr, or, thirty cubic feet houii> , 
alloiring H. 22 lbs. of caking coal for evefy rt; 
foot of water. 246.6 lbs. of aucb coal would : 
ronnamrd hourly; or, dividing 3i&.6 by tt.M^ 
9.2 Iba. of coal per honr for each horae powvr. U 
is said by some that the foci consumed is aboot oo*> 
half mure than thia — 14 or 15 lbs. per horae povtr 
hourly ; this is the more general estimate. 

In an engine working expanaively, the steam betof 
cat off* at about one* half i-^) of the stroke, iht 
mean force would be 4.8 lbs. on drcular incfc. 
This, multiplied as abore, would give iV94,432 lb«. 
raised one foot per minute, or, dividing by 33,400« 
eighteen horses* power. The fuel required, wo«li 
be about one-lialf (^), 117 Iba. per hoar, ar. 6^ 
Ibf. per hone power, hourly, about 2.7 lb*, pv 
horse power being saved every hour. 

In a doable-acting engine, of abont twotty 
power, the diameter of the piston is aboot 24 
its area being 452 squai'- inrl^i^. or 22.6 
for each horse power. T)ir> vflectivc 
the piston msy be about /.3 lbs. per aquara look 
The length of stroke will be five feet, it will naka 
twenty strokes per minute, and iu velocity t»c 200 
feet per minute. Such an engine would raisa 
660,000 lbs. one foot high per minute; and ODOf 
Bume hourly 166 Iba. of coals, or 8.3 Iba. ptr beat* 
pnwrr. In smitUcr engines, the prvaaor* on I^A 
piston is less, and the consumption of fa«l graa&M^ 
In Urge engint» the reverse. In an engina d MO 
horse power, the effecttve pressure on tbe pisKM 
rany be abont 6.9 lbs. per square inch, and, tkt 
coaj consumed hourly is, per bofM-power, oolf 
5.5 lbs. 

Mr. Tredgold estimates the dedoctiona to bf 
made from the force of the steam in the boilct In 
high-pressure engines, at about 0.4, the vbola fsMI 
being 1.0. The cffeciive pressure ihoa. is 0.1^ 
To find the power of a bigh-pmuiure engine, maltl* 
ply the excess of the force of the steam m tbe bolkt 
over the atmospheric pressure by 0.6 1 sabtnO 



* A sfroAv moans a mcUon of tt 
tha c«lUid»r to iho tiotiom. sro 

lengiA or • •triilte ki ajtxkaii of. <'u,, ....: i„. ..; 

mitanL Tiu^, ir Uio lenfih of vtroke tw Avt laak tM 
will ttc t«n ftofl 



3*f 



MAGAZINE OF SCTENCE. 



J43 



Inct 4*10tiu of Ihe preunre of the air 
■ oirenUr int^ ; multiply th)« product 
of the diiimctcr of Ihe cylmUer, and 
id bj the velocity of the pUtuD, giveA 
of pounds Tiostd one foot high per 

>Ofttruction of the boilers of mtrine en< 

coDSume lesi fuel than land eDgioeK. 

the propurtioQ of two to three. Slemon- 

now be expected to run at the rate of 

ito 260 miles per day (allowing for bud 

III stoppages for repain), and, as nt pre- 

icted, may cury fuel for ■ voynge of 

miles. It is probable that the ue.e of 

vapor engine, or others, may considerably 

distances which steam. vessels esn run 

fresh sapply of fuel. The consiuopt of 

im-boat engines seems to be in general 

lbs. of coal per hour for every horse- 

ing table shows the relative beating 
the chief sorts of fuel io use for steam- 

Ponadi *t wain co«- Fonnds of ftitl rt- 

verted lalo iteam c( qulrvd to (orm a 

mP (froni S?') by cubtc footof wktcr 

' of fusl. Into aUain. 



, 94 Om. 

MS « 

T-T « 

1.1 • 

, Ml • 

%» « 

4.19 * 

1«9 » 

iM m 



r.45 


Ito. 


»Sf 




e.1 




SUCH 




lis 




lar 




uy 




22.0 




ITS 





itlof thcquantity in practice Mr. Trcd- 

wbom \m above table is taken, adds 

10 per cent.) ; thus making 8.22 lbs. of 

Uie quantity necessary to vaporize ■ 

of water, A cubic foot of water weigb« 

avoirdupois. Equal beating power 'a 

from 1 of Newcaatle coal. 1-^ of Ulaagow 

irood, and about twice aa much culm as 



THE OCEAN. 

is that vast body of water which snr- 

continents, snd is the receptacle of all 

ting waters. It is divided by geographers 

ffreat basins ; vix. the Pacific Ocean, (so 

reason of its comparative stillness), which 

Asia from America, and is the largest of 

ins; 2. The Atlantic Oceaa* which has 

\A Africa on iti eastern shore, and America 

3. Tbe Indian Ocean, which washes 

of Asia, and the &outh>eastem coast of 

j^. Tbe Arctic Ocean, which surrounds the 

and ft. The Antarctic, which surrounds 

pole. Orher smtllrr portions of the great 

body of water are culled «fa«, uf wliich 

SfraoesD, the German, Ihe Baltic, and 

t, are tbe most considerable. The super- 

of the several great baains is not known 

certainty, nor. indeed, can their limits be 

loed. From the nearest eatimation that 

le of the extent of the continents aiui 

lalands, it is supposed that nearly three- 

' the whole surface of the globe are covered 

Tbe Pacific Ocean alone exceeds the 

face of the dry Und. 

(j^ ikt Octan. — If the raperflrial extent 
Cftouot be easily ascertained, it will 



readily be supposed that its depth ie a probteta of 
much greater difficulty. The bottom sppiMirs, 
wherever it has been reached by the sounding line* 
to have similar inequalities to those of the surface 
of tbe land : hence the depth must be extremely 
various; aiid it might be supposed frurn anolngy 
that the greatest depth of tbe ocean is at least equ^ 
to the height of the highest mountains above ita 
surface. Lord Mulgrave found nu bottom in tbe 
North Atlantic Ocean with a sounding line of 4(tiiO 
feet ; and Mr. Scoresby lounded to the depth of 
720U (rrt, without tbe lend touching the ground. 
These experiments are not altogether to be depended 
on for the determination of such great depths ; for, 
the pressure becoming very great, the lead may be 
drawn out of the perpendicular direction by currectts . 
of which it may encounter more than one, flowing 
in different directions. Over a great portion of the 
Atlantic and Pacific Oceans no bottom has been 
found. The depth of the ocean in general, ond tbe 
form of the bed on which it rolls, cannot, therefore^ 
be determined by experiment. The mathematical 
theory of the oscillations of fluids ban, honever* 
thrown some light on the subject. Laplace de- 
monitratcd that tbe dilference which is iudiculed bf 
obtervatioo between the height of two consecutive 
tides depends on tbe law of the depth of the aes, 
and that, but for the inflocDcc of accessory cir- 
camstancea, it would disappear altogether if the 
depth were constanL It fullowa, therefore, that* 
since the difference between tlie consecative tides is 
extremely small, the depth of the sea, taking la a 
large extent of oci»n, must be nearly uniform ; that 
is to say, there must be a certain mean depth from 
which the variations are not coniidersble. 

£«?#/ of the Ocean.— Were it not for the dis- 
turbing actions oT the sun and moon, and of tbe 
winds, tbe level of the ocean would be every where 
the same, and its surface would have tlio form de- 
termined by the attraction of the whole mass of tbe 
earth, eombined witb tbe centrifugal force belonging 
to its velocity of rotation ; that is tossy, tbe surface 
would be that of sn oblate spheroid of revolution. 
This uniformity, however, can never be establi«hed. 
The tide at every instant is at different heights in 
different parts of Uie ocean ; and therefore the form 
of the surface, within tbe limits of tbe nJK and fall 
of tlie tidei, is variable. But even if we neglect the 
alternate rise and fall of the wster nhich constitutee 
the tides, and take the surface of the ocean u tta 
mean height, it is found by sccurate levelling that 
all its parts do not roincide witti the surface uf the 
same spheroid. Gulfs and inland seas, which com- 
municate with tbe ocean by narrow npcnings, are 
affected according to their poaitlon with regard to 
the prevailing winds. Tbe level of the Red Sea waa 
found, by the French engineers in Egypt, to be 32| 
feet higher than that of the Mediterriinean, wblofa 
is supposed to be a little lower than the ocean. 
Humboldt concluded, from obscrvitioni made on 
the Isthmus of Panama, that the waters of tbe Gulf 
of Mexico are about 2 feet higher then those of the 
Psciflc Ocean. Tbe Baltic and Black seu rise in 
spring from the great quantity of river water poarad 
into them, end are lowered in summer by the joint 
effects of a small supply and increased evaporation. 

Color q/" /A« Ocean, — Tbe usual color of the 
ocean is a bluish-green, of n darker tint at a distance 
from land, and clearer towards the shores. Accor- 
ding to Mr. Scoresby, tbe hue of the Greealand aea 
varies from ultramarine blue to olive green, and 
from the pureat transparency to great opacitx. The 



844 



MAGAZINE OF SCIENCE. 



rarfioe of the Mcditsmnean, in iu upper pnrt, ii 
•aid to HiTc nt times n [lurple tint. In the Gulf of 
Guinea the ua somettmes appeani white ; about the 
Maltltve Ulancla black ; and near California tt has 
a reddiih appearance. Various causes co-operate 
to produce this diTeraitr of tint. The prevailing 
blun color maj be aacribed to the greater r^fraii- 
gihility of the blue niys of Light, which, by reason 
of that property, pass in greatest abandance throogh 
the water. The other colors are ascribed to the 
existence of vast numhrrs of minute animalcnlie ; to 
marine vcj^otubles at ur near the nrface ; to the 
color of the aoil, the infusion of earthy sabstaiicea ; 
and very frequently the tint is modified by the aspect 
of theaky. The phosphorescent or shining appear- 
ance of the ocean, which it a common phenomenon, 
ia also aacribed to animalculie. and to semi putrescent 
natter diffused through the water. 

Temjjfriiture of thf Ocean. — Water being a alow 
conductor of heat, the temperature of the ocean is 
muLb more uniform than that of the atmosphere. 
At a certain distance from the equator, it follows, 
though not very closely, the moan temperature of 
the correaponding latitudes ; the solar action being 
greatly modified by the existence of currents which 
convey the temperature of one region to another ; 
so that at any place the temperature of the water 
depends in BOtne measure on the direction of the 
ctirrents. AVithfn the tropics the mean temperature 
■t the surface is about HO" of Fahrenheit, and ge- 
nerally ranges between 77° and 84". At great depths 
the temperatare is probably nearly the s&me under 
every Intitude. In the torrid sone it is found to 
diminish with the depth ; in the polar seas It in- 
creases with the depth ; and about the latitude of 
70" it is nearly constant at all depths. Bnt the 
■mall number of obaervationa which have yet been 
made on this subject do not indicate any uniform 
law, according to which the variation of tempera- 
ture at different depths is regulated. 

Sttl/nen o/ the Ocean. — The ocean holds in so- 
lution a variety of saline matters, of which by far 
the most abundant is common salt, constituting in 
general about two thirds of the whole. The salt- 
neia of sea-water at particular places is influenced 
by temporary causes — storms, for example ; ai well 
as by the ueighbourhood of large rivers, and per- 
manent accumulations of ice. A series of expe. 
rimenta on this subject were made some years ago 
by the late Ur. Marcet ; and the following are the 
general conclnsions which he dedaced from them : — 
i . That the Soathem Ocean contains more ult than 
the Northern Ocean, in the ratio of 102919 to 
X'02757. 2. That the nuun specific gravity of sea- 
water near the equotor U 1 '0277 7. 3. That there 
IB no notable difference between aea-watcr under 
different meridians. 4 . That there Is no satisfactory 
evidence that the sea at great dcptha Is more lalt 
than ut the surface. 6. That the sea in general 
cnntain^ more salt where it ii deepest ; and that its 
sflltnrss is always diminishrd in the vicinity of Urge 
masses of ice. 6. That small inliind sea*, though 
communicating with the ocean, are much less salt 
than the OTfan. 7. That the Mediterranean con- 
tama rather Larger proportions of salt than the 
ocean. 

'i'he peculiar bitter taste of sea-water does not 
appear to belong to it beyond a certain depth, and 
it ascnb(>d to the vegetable and animal matter held 
in a fiate of decomposition near the surface. 



MECHANICAL DATA. 

The first iron rail-road was laid down at Col 
brook Dale, 17H6. Near Newcastle, tliere an 250 
miles of iron rail-way above ground, and nearly th« 
same beneath. In Glamorgaoihire there are 300 
miles, from different coal-works and mines to qntyi* 

An undershot wheel has the greatest forre w) 
its circumference moves with five-sixths of lh« 
velocity uf the stream ; and the best velocity of 
overshot wheel is 3 feet in a second, and depends aiS 
proponioniog the buckets, the power of the 
being as the height it falls through. In the ondv- 
ahot wheel the power is to the effect as 3 to 1, 
in the overshot wheel double, or 3 to 2. 

One hundred pounds force of draught, or traetiou, 
at 4 milea per hoar, draw IS, 000 lbs. on a ooasl; 
11,000 on a railway, and MOO on a turnpike. A( 
10 milea, 2hm lbs. on a canal; 11,000 on a nfl- 
way, and UOO on a turnpike. A horse wfaost 
traction is 83} lbs. will, in S hours, at 3 milet an 
hour, draw 240 tnna on a canal; 92 on a railway, 
and 12 an a turnpike : or, in 2 boars, at 6 mili^ 
will draw 30 too* on a canal ; 48 on a railway, 
6 on a turnpike. 

StoDc* for roads are broktti to G ounocs, M 
rounded pebbles do not imbed. Ten Inches depth 
of well-consolidated materials are enflkient, wUl- 
ever the substratum, and better soft Ihan bard or 
rocky. Five tons of sized stonei over a mona 
last OS long as seven on a hard bottom. — M'AdmL 
Seven or eight degreea ia the greatest angle far 
carriages, fifteen degreea for beasts of harden ; ani 
thirty-five degreea cannot be ascended by a maa 
without steps, and even with stey forty-fonr dc^gites 
is very difficult. — Savmure. 

There are now in this country not less that 
15,000 steam-engines at work, some cff lOUO hone- 
power. Taking ic that, on an average, these rngiMi 
are each of 25 horse power, this would be eqoal la 
375,000 horses. Five men and a half are equal It 
the power of a horse ; we have thus, thercion^ • 
power, through the medium of atcam - engines, j 
to Dear two millions of men. Eaeh hone 
keep per year requires the produce of two 
land, and tlius 750,000 acrea are at the dii| 
the inhabitants, more than if the same work, 
ia now done by steam, were performed by honied 

One of the most powerful steam-engines, ti 
Englsnd, is that erected at Hawkesbury CoUtivT, 
near Coventry. Its cylinder it 68 iitchea ia di*- 
meter ; the piston moves H feet in a stroke, m^ 
makes 12 strokes in a minute ; the puiup u 
inches in diameter, and the lift ts 65 fathoms. 

Ia 1751, a globular bottle wai blown at Ti 
capable of holding two hogsheads. Its di 
were 40 inches by 42. The largest ever 

A landscape in perspective should not it 
more than an angle of 60 degrees. ■ 
the horixon. All lines perpeudicu! ii 

or perspective plane, vanish in the yy< 
and the size of objocta is therefore inversely as) 
distance. 

Owing to the centrifugal force, it is easier to it 
feats of horsemanship in a small ring, as at thatm> 
than if the animal were running on a straight rc*^ 
The man and horse always inclining Inwirdit ^-^ 
counteract the cenlriftigal force, and if the niWi 
tend to fall inwards, he has merely to quickra tbi 
pace ; if to fall outwards, he has to aUfJien it 



II 



liar 



Loiaov.— PrtnlMl l«y D, ysAMoii, fi, Wh'.ta llnrM Lam. MjI« Rnri— PaliUihMl by W. BatwAiK. 11. 
Kjlnbur^lj, J Mxr.ika.— GlDipiw, II D«ici ami J B*KS»*.-'L.iv(n'poii), O. PaiLtr. 



34G 



MAGAZINE OF SCIENCE. 



HOT AND GREEN.HOUSE THER- 
MOMETERS, fee. 

Tiia girden indic&Eort of wcalher ditTer from Uiobb 
in commoa un only in two instuicefl, that of the 
mistering thermometer and regulating thermo- 
meter ; together with such flight Timalions ia the 
form of the qkuiI instruments as better adapt them 
to the eirctimHtanrca in which thej are to be uicd. 
One of these slightly-Tiiried in6trument» 1* Rrrga::i*9 
l{ot-f*itHM¥ YhrnHom/fter: it has a double bark, the 
Advantage uf which ii, that when hung from tlie 
roof of the hot-house, the heat of the sun is pre- 
vented from operating on the back of the bulb of 
mercury, by the cnrrcnl of air which puijscfl between 
the backs. Another blightly-vani'd instrument is 
J9reyflj;i'* Sarl-Oed TAemiomelcr (Fii*. I), which 
has the bidb inclosed in a pointed ghus tube, by 
inicrlin; whicli in the barkbed, or in rarth or 
water, tlie temperatare will be indicated according 
to the depth of insertion. The risible part of the 
glass tabe is protected by a small door, near the 
upper end of the initrunient. Sir't Regixtering 
Thrrmomnter, of which a ligure ia given annexed, 
il so contrived aa to indicate the extreme points to 
tt'hit^h it falls or rises in the coarse of the day or 
night, and is, therefore, pnrLicalarly useful as a 
check upon the working gardeners, who have to at- 
tend to the firra, i»team. &c. of hot-houses in the 
winter time. In the open air, and for ordinary 
meteorologicnl observations, it ia also a very itbcful 
iuatruroent, from its pointing out the rxtnimes of 
temperature. Its dcacriptiuii is as follows : — 




Tt b « spirit of wine thermometer, with a long 
cylindrical bulb, and a tube bent in the form of a 
aiphon, with parallel legs, and terniinatiog io a small 
cavity. A portion of the two legs of the siphon 
from' A to B is tilled with mercury ; the bulb and 
the remainder of both legs, as well as a small por- 
tion of the cavity, are filled with highly -rectified 
aud colored alcohol. Tlie double column of mer- 
cury'is intended to give motion to two indices CD; 
the form of which is better shown at the side. Each 
index eonsists of a bit of iron wire, inclosed in a 
glasa tube, which is capped at eacii eitremity hy a 
button of enamel. Their dimensions are such, that 
they would move freely in the tube, were Jt not for 
fl thrtad of glass drawn from the upper cap of each, 
and inclined so as to press against one aide of the 
tube, forming a delicate spring of sufficient power 
to tettin the attached index at uiyparc of the tube 



to which it is driven by the mercury columa. Wfcen 
heat expands the spirit in the bulb, it drpr^4.p* thn 
mercury in the Uuh A, and proi>ortiouat> 
in B, and with it the index ; this UkL 
ftxed at the highest point that the mercury ruu-iie^ 
On ilie other hand, a decrease of teoiperature allows 
the side A to nse. and to carry up also its \uAtx ; 
and thus the highest and lonest temperature tine* 
the last examination i>i the instramcnt is regtstert^. 
The indices arc again brought down to the rarfac* 
of the mercury, by holding a small magnet towards 
them. 

KfteUj/'i Alarum Thermomfifr (Fig. 2) oooabli 
of a gloks tube A A, about 10 inches in IciiftKi 
henneHr-ally sealed at one end, and united al xhe 
other to a capillary tube BU, withau Intrr^cmni; 
niid also a terminnting ball C and D. lmai;ine Ihu 
double tube placed in a borixontal po«itton, thf 
largest tube, and half the intervening ball. Ailed 
with spirits of vine ; and the smaller tube and luK 
of both of the balls, with mercury. If the tube is 
now fixed hy its centre in s brass frame E, aA4 
nicely balanced, it is evident that ever^ change is 
the temperature uf the atmosphere will produea ft 
change in the position of the centre of gravity cf 
the tnbcit. One degree of heat, by expanding (be 
spirit, will press on the mercury in the intcrreiiin 
boll C, and drive part of it oier to lite tcrmioaltsf 
tub? D. which end will, in conseijneoce, dnocsid 
like tbe beam of a pair of scales, or of a st«s«- 
engtne. Hence a moving power of great nicety nJ 
certainty is obtained, the details for tbe appUostioa 
of which, to the ringing of a bell at any distaoct, 
commanicating by a wire F, need not be here eatifrtd 
into. Suffice it to say, tliat, by means of a Md» 
G it may be set to any required temperature, and 
will give the alarm at a difTerence of even the foqrih 
of a degree, either of depression o^ elevation. It 
may be occasionally used in gardt^mng, to coatQ 
some idea of the changes taking place in the fictt- 
perature of particular hot-bouses, to the head- 
gardencr's room, in the night-time ; but its OWVt 
important useii sre in domestic economy, hotpitdl, 
tec. This balnnce-therraometer, as it may l>e csllad, 
hftt been also applied, by it8 ingenious inventor, to Iks 
opening aud shutting of windows or sashes, T«)tcs 
of chimneys, or fines, and steam-cocks, and eUhcr 
to alt of Iheie purposes at once, or to any of thrsi. 

Aetp/ey's Rfffulating Theitnomettr, or AutowMlv» 
Gardener (Pig. 3) consists of a per*'-'"'-' "'-T^iica- 
tion of the alarum-thcrmomt'ter ju^' For 

this purpose, the thermometer is niri -j t© 

three feet in length, and the same principle msy be 
extended to any length, as ten or twelve feet, with 
a proportionate increase in the diameter. The l|U 
paratus which Kewley appUei to the thenDomttfi 
and which enablea him to get the power re^i 
for opening the eashes or windows of hot-hoi 
buildings of any magnitude, is a metal cylia 
generally of rolled copper, as being che»pe»t, fr«ia 
seven to fourteen inches in diameter, and fnm 
eighteen inches to two feet in length, with an aff> 
curately-fitted piston I. Thia cylinder is pladll 
either within or without the hot-house or roon, l> 
auy convenient situation, and a ciktero, or a bvnli 
of ordinary dimensions, tilled with water, is plaDed 
on an elevated silualioo, say on a level with the 
chimney-tops. The deeper the cylinder u mxX, 
the less the cistern requires to be raised sbove the 
level of the floor of the house. If, ss is oftca thii 
case, a pipe of water is coiulQcted through the lK*«ac 
from a distant reserroir of ordmtry dcvaUon, 



MAGAZINE OF SCIENCE, 



947 



nothing move is neresfliiry than attachins • bnnob- 

pipe, ll ii reqaiaitfi that thtf pipe puis directly to 

tiie point whcrt; tlie tJiermometcr ie placed, ami at 

-«-.....,,, f.,ji(.|,t diautice under it, not higher thau 

iQ of the cylinder. Here it is jotued to > 

■ i; ■ cork K, whence proceed two other pipe«i 

one L to the rjlinder, nnd th« oliirr M to a waste 

drain. The ito)>pcr to this cock tiini* ooly to the 

of aboQt oiit-firth of a circle; and when 

to tUiA exteut tu tbe right, it opena a com- 

ition between the supply. pipe N, aiid tJie 

cyliader H, when the prciaure uf the water in the 

retenoir. whether a barrel ou the top of a houic, 

or a diitant ei&ternf raism the piston, and by a 

CJmmunicatiou of cordu and pulleys with the sa^hca 

O. tiiey will be rai^^d or openod ; and by another 

r. the fire or iteam damper Q will be opened 

W'hen the cock is turned to the left, this 

rnnUratian is stopped, and onr. opened between 

cyUndcr and waste-pipe M, by which tlie water 

escaping the piftton dc<cend», nnd the sashes and 

daiaper« arc shut. The equilibrium of the balanoe- 

theraiu meter restored by tlie tcmperaturot being 

rHnr**d nr elevated to the proper degree, the plug 

f turned to the right nor left, and every 

I .ttion is clooed. The cock is wurked by 

• R R, fBSt4.'ned to two short levers, fixed 

«ide of the thermometer-frame, and the 

„j — 1 v.Js of the cross or handle of the cock S S. 

It the machine at work, it is only necessary to 

the scale to a degree at which it is desirable 

>l be given, taking care that the ciatern is 

at water. A sinuU cask of water regularly 

inpjili'd, will nuairer us wrll as a large cistern, as 

the power is not as Uie body of water, but as ita 

height. As a hot-house seldom remains many 

■linutes at the same degree of heat in the daytime, 

it i< evident that the sashes would be in almost 

I nititioo, which, in bouses where tbestsfaes 

ruArds, would have u singular nnd ■oimntrd 

dfect in a flower-garden, or on a lawn. Where 

]%ht valve* or venttlntors are used, the balance- 

Mimnomecer of this size has sufficient power to 

them without the aid of machinery ; and by 



»*Tv*»i-w.>iin» itic IS,., sufficient power may be ob- 

ti windows in dwell ing-honses, 

''.-'. Thia machiue was originally 

iiir the use of the inventor in hia own 

I DougUs (Ule of Min), and wit tuocesa- 
fultjr ciiiployrd to give air to pits and franies there 
for two seasons. Having come to London, Mr. 
Krwl«y employed it with the addition of more ma- 
chinery thfin be now uses, to ventilate a part of a 
aDQ*^ ill the New Kent Road, from IH16 to 1817. 

iir greatly simplified it, and thus improved, 

II operalioa on ■ hot-house in Colvill'a 
Mjinuy* King's Iload, during the aummrr of 1819. 



CEUOGRAPHY. 

Ay arrount has appeared in the American papers 

of a new method of engraving, the nature of which 

appears tu be uiil<n»^n, thuui^h specimens have 

been pnhlished. 'l^e editor of the Uotiton Daily 

Mr^^ftArr !Miys be has endeavoured, but without 

t I form some conjecture as to the manner 

'lie work is executed, — " Being printed." 

( «, *' on a Urge sheet in common with 

[iress of a targe newspaper, the |dutemust 

character of a wood engraving, yet it 

^Imoit the delicacy of a copper. pUte en- 

Kitd abuunds iu lints which arc evidently 



impracticable in wood engrariog. The nnilormity 

of the lettering, although varied by the diversity of 
characters afforded by the use of different founts of 
type, shows that this part of the work is of the 
nature (if stereotype ciutiog, hut in what manner 
the shading, roads, nnd other arhitrury lines arc in- 
fcrted, it is ditUcidt, from an inspection of the im- 
prcHSton, to imagine, uott-ss it be by some process 
uf etching. From what is staled by the inventor, 
of the rapidity and cheupnesa of Ute execution, the 
sixe to wliich the plate may be ciklciided, it& adapta- 
tion to the rapid and cheap mode of printing, by 
which the ordinary book and newspaper printing is 
cvetnited, we cannot but regard it as a very im- 
portant end useful invention, particularly applicable 
to the printing of maps and drawings, in connexion 
with lelter-preas, for the ittostration of worka of 
aloaost every description." The Ntw York O^teiver 
further states — " The advantages of oerograpby are, 
1. The engraving of many subjects can be executed 
vrith a rapidity approaching very near to tliat of 
drawing upon stone ; and tlie wholu ezpenae of m 
phite prepared for the press will ordinarily be less 
thAn that of a plate in copper or wood. 2. The 
plate is durable tmder the press. A million good 
copies niHy be struck from it ; and as it can be 
stcn^typcd, the nujnhcr of plates may bt! uiuUiplicd 
indefiniiclv ut a trilling expense, and e^rh plate will 
give a million copies. 3. Luiea of all rngravinga, 
except, perhaps, the very finest class, can be made 
witti nearly or quite the same perfection as in cop- 
per or steel, and with lens labor. 4. We know of 
no limit to the aize of cerograpluc plsleji. We 
suppose they may be made as large as the bed of 
the largest Napier press. 5. The printing is exe- 
cuted wlUi the common printing press, and of coarse 
as rapidly as wood-cut or letter-press printing. 
Witii this statement, our readers can judge, u well 
as ourselves, of the eifects which cerugraphy, in the 
hands of orcoRiplished artists, will probably produce 
on the other arts of engraving. We suppose that, 
wich an imprLtTcment of which it is evidently sus- 
ceptible, it will also have on iiiiportant ctTect on the 
art of printing, especially on printiug in the cha- 
meters of the Chinese, Hindoo, and other Oriental 
languages. Even m its present state it will, no 
doubt, be used as a substitute for type-setting in 



ARTIFICIAL STAINING OF MARBLE. 
This art was practised by the ancients, and is de- 
scribed by Zoaimua: it is now making cf>nsidrrabte 
advance at Vcrono. The results are as follows : — 
A solution of nitrate of silver pciiLtrates the marble, 
and communicates a deep red color to it. A solo* 
Lion uf nitrate of gold penetrates leas deeply, and 
commuotc^ktes a beautiful purple violet cidor. Vcr- 
digriM sinks to the depth of a line into the marble. 
and gives a Ano green color. A sutuiion of dragon's 
hlood cunimunictttes a beautiful red ctdur, and 
gnmbogB a yellow tint. To apply these two colors 
it is necessary to polish the marble with ■ pumice- 
stone, to dissolve the gum resins in hot alcohol, and 
put them on with a camel<hair pencil. The tinc- 
tures obtained from woods, as Braxil wood, log- 
wood. &c.. penetrate deeply into marble. Tincture 
of cochineal, with the addition of a little alum, 
gives marble a fine scarlet color, simtUr to African 
marble. Arliiimu! orpiment produces, when dis- 
solved in ammonia, a lively yellow color. If ver- 
dict ise be boiled wiUi while wiu, and the mixture 



348 



MAGAZINE OP SCIENCE. 



be applied to the marble, and then rrmoTed when it 
hai cooled, it will be foand to have prnetratrd five 
lines, and to baTo produced a fine emerald color. 
\^Tien it b wished to apply the different CDlora in 
Bucce^aion, some precautioas are necesiary. The 
tinctures prepared by spirit of mne and by the oil 
of turpentine are to be applied to the marble while 
it ia hot; but the dragon's blood ind gamboge are 
to be oaed with the marble when cold. For this 
purpoae, it is necesaary to diasolve them in alcohol, 
and employ the solution of gamboge tirit. Thi«, 
wtiicb ia clear, pood becomes turbid, and affords a 
yellow precipitate. Those parts of the marble 
which are covered with the tincture arc then to be 
heated, by pai!>&ing over them, at the distance of 
half an inch, a red-hot iron plale, or a charcoal 
chauffer ; it is then allowed to cool, and the iron is 
to be again passed over those portions where the 
color has not prnetrated. When the yellow color 
has been imbibed, a solution of dragon's blood is to 
be apphed in the same manner; and, while the 
marble ia hot, the other vegetable colora may be 
communicated. The last colors to be applied are 
those in union with the wax. These mutt be used 
with ^rt&t cantion. because the alic:htest excess of 
heat causes them to penetrate deeper tlinn ia necea- 
tory, which renders them less adapted for delicate 
work. During the operation, cold wuter should be 
oocaaionally thrown upon them. — Athenaum. 

STEAM AND THE STEAM ENGINE. 

( lUiumrd from pagt 333. > 

It will be seen how very little hod. till the time of 
tlie Minjuii of Worcester, been done towards the 
formation of the ateam.engine; so little, indeed, 
that we may consider it to have been scareely in- 
vented at all, not a single part of even those given 
as the Marqnis's agreeing with the engines of 
modern use ; henceforth, however, inventions and 
contrivances will he found to succeed each other 
rapidly, each engine containing some important ap> 
pcndage, which preceding ones were without. As 
the first and most important of these, we mov men- 
tion the inventions of Dr. Papin, a native of Blois, 
a man of great ingenuity, and of considerable ac- 
quinroients as a philosopher, is considered by his 
eottntrymen to be the true inventor of the steam- 
engine. It is certain that he is the first who sug- 
gested fAe ffl/e/y pfl/pc. Papiu'a firtt project, and 
it is necessary to keep this in remembrance, was to 
procure a first power by an air-pttmp. This scheme 
he announced as a means of enabling him to trans- 
mit, to conHiderable distonres, the action of a mill 
by means of pipes. Tbt cylinders of air-pomps, 
at one extremity, ware made to communicate by 
pipes with equal cylinders, placed at the other and 
distant end, which, by some intermediate me- 
chanism, were there connected to the piston rods 
of the pumps of a mine. This projert failed eten 
on tlie smnll scale of an experiment, from the pro- 
digioos resistance of the pi<ton. Papin next tried 
to obtain a motion in a cylinder by the explosion of 
gunpowder, but here again it was found that with- 
out codangeriDg the apparatus it was impossible to 
obtain power enough. He next saggested the em- 
ployment of Mteton for forming the vacuum under 
the piston, and also for raising that piHton by its 
lasticity. In this paper, which was poblishtd in 
1690, he shows, that in a little water, changed into 
steam by means of tire, we can have an elastic 
power like wr, but that it iguUly disappears when 



chilled, «nd ehaofea into water ; by vhkb tamaa 
he perceived that he could contrive a machioa lo 
such a manner, that with a smalt fire he wooJil be 
able, at a trifling expense, to have a perftfct Taeaaa, 
which he admitted could not be obtained by gvi- 
powder. His was a happy thooght, and had Fana 
persevered to make the experiment, he would, 
beyond all question, have produced the atmospheric 
engine; and although we cannot refuse to do (^ 
ingenious man the great honor doe To having gitea 
the first idea, the merit of putting the acheme tafia 
practice is certainly due to another. 

It was at this period that Captain Sawrr, a se^ 
faring gentleman, offered an engine of hta lorenttoo 
to the notice of minerm, which ahowed as much ia- 
genujty, depth of thought, and mechanical skill, as 
In any project of the age. He obtained a patem id 
1B9B, after having pnbluhed an account of it two 
years previously nnder the title of The Mmm** 
Primd. 

The following rut is given in Harris's " Lexieon," 
and the descriptioa of the engine is i« the words al 
Savery's pamphlet, pablisbed ia 1702 : — 




"The first thing.'* lays the ingentous iowBtv. 

" is to fix the engine in a good double fnma«^9, 
contrived that the flame of your fin may 
round, and encompass your two hotlera, a 
coppers for brewing. Before yon make aof] 
unscrew G and N, being the two BmaTl gaugei 
and cocks belonging to the two boilers, 
the holes fill the great boiler, two-thirds ftlll 
water, and D, the small boiler, quite full. Th«s 
screw in the said pijtes again as fast and ;• 
possible. Then light the fire at B ; 
the water boiht, the handle of the fv^ut 
marked Y, mtut be thmut from you as far 
will go : which makes all the steam rising froal 
water in L pass with irresistible force tliro«fb' 
into P, pushing out all the air before it, throojli 
the clack R, making a noUe as it goes : and vba 
all is gone nut, the bottom of the vessel P will ^ 
very hot. Then pull the handle of the regulal 
you, by which means you stop O, and forea; 
steam through O into the other P. until that 
has discharged fU air through the cluck R up 
foroe-jti|ie ^. In the mean time, by the tinm'* 



MAGAZINE OF SCIENCE. 



349 



^in the vessel P, a Tamaoi or emptinesi it 
ll that the water must and will neocuarilf 
tough the flurkini^-pipe T, lifting up a 
pfiUiag the vessel P. 

It mean time, the other Tcsael P being 
i^ air, tnm the handle of the regulitor 
ain, and the force is upon the surface of 
P ; which turface being only heated by 
h does not coodense it, bat tbe steam 
pruRcs with an elastic quality like air. 
ig its clostieitj or spring till it counter- 
I rather eiooeda the wnght of the water 
b B, tbe forcinK-tMpe, out of which the 
I will be inimedmtely discharged, wbrn 
^ to the top, which takes up some time 
|Uiat power ; which having otice got, and 
prk, it is easy for any one that never saw 
L after half an hour's experience, to keep 
fttream running out tbe full bore of the 
(the outside of the vessel > you may see 
iRter goes out as wall as if the veasel were 
R; for as fr as the it«am continacs 
\ vowel* so far is the vessel dry without, 
1^ hot, as scarce to endure tho least touch 
U. But as far ob the water is, the said 
I be cold and wet where any water has 
It ; which cold and moisture vsnishes as 
Fsteam in its descent takes place of the 
I if you furre all the water out, the steam, 
:'part thereof, going through 11, will r»ttle 
'«u as to give suffitneot notice to pull the 
the regulator to you, which, at the same 
h» to force out the water ftom P, without 
Uteration of tlie stream ; only sometimes 
I of wstrr will be somewhat stronger than 
o pull the handle of the rrgulator be- 
iderablc quantity of steam be gone up 
but it is much better to let none of 
go off (for that is but losing so much 
and is easily prevented by pulUng the 
me little lime before the vessel forcing 
paptjed. This being done, immediately 
bck or pipe V of the cistern X on P, so 
Iter proceeding from X through Y (which 
pen bat when turned on P, but when 
em U tight and stAncb) — 1 say, the water 
P( eaoses, by its coolness, the steam, 
d BQch great force just before, from its 
prer, to condense, and become a vacoom 
Itotce.) so that tbe vessel P. is by the ei- 
L or what is vulgarly called suction, com- 
pUcdi white P is emptying. Which 
|L you push the handle of tbe rrf^nlator 
I and throw the force on I', pulling tbe 
v-pipe over P, causing the steam in that 
|voodense, su that it fills while the other 
IJThe labor of turning those two parti of 
$, vis. the reguloior and v:afrr'eock, and 
|C fire, being no more than what a boy's 
kn perform for a day together, and is as 
lied as their driving of a horse in a tub- 
kfter all, I would have men, and those too 
lapprehensive, employed in working the 
^iposing them more corefttl than boys." 
Wtating that an engine mising a column 
pO feet high and 3\ inches in diameter, 
I fire*plBce 20 inches deep, and II ur 
I' wide ; Sarery gives us no inf«rmation of 
of his engines in T/te Miner' » Friend. 
ng in that book c^iinuot be dc|veiided 
correct pniportiuus uf the dcUils. 
Bradieji who wus professor of 



botany at Cambridge, gives a dcscripcioD of a tmsU 
engine having only one receiver, erected by Savery 
liimself about 1711, for a Mr. Ball, at Camden- 
housc, KeostDgton. It was standing in Switser's 
time, who says it was the best proportioned of any 
be had seen. This is represented t>elow : — 





The pipe G is 16 feet long, from the surface of 
the water H to the stage on which the receiver B 
is placed. And this is the height to which tbe 
water is raised by the pressure of the atmospbete. 
The height of the reservoir above the receiver is 
about 42 feel; and this column of water was cle^ 
vated by the elaaticity of the steam. Tbe pipe L 
is 3 inches in diameter, and the steam pipe D about 
1 inch bore. The receiver holds 13 gallons, and 
tbe boiler 39 gtlloni. 

Its operation is the same as that of the machine 
shown before ; the steam admitted from the boiler 
B into the receiver E, is condensed by turning the 
cock M, which allows tbe cold water to fall on the 
outside of the receiver, at the same time that the 
flow of steam ftom the boiler is shut off by the coek 
C ; a vacuum being thus produced in tbe receiver, 
the pressure of the atmosphere raisea the woter in 
tbe reservoir up tho pipe G, and fills the receiver E. 
The cock M is now closed, and the communication 
between the boiler B and the receiver E is again 
opened by taming tbe cock C ; the elasticity of tbe 
steam then forces the water in the receiver E up 
the pipe L ; the vslve at F opening upwards, pre- 
vents it from returning. When the receiver is 
again 611ed with steam, tbe cock C is shut, and the 
cold water or condensing cock M is opened. This 
condenses the vapor, and forms a vacuam, and the 
pressure of the atmosphere again acts to raise the 
water in the reservoir through the pipe G into the 
receiver, which is forced up the pipe L by the 
elsstirity of the steam, and so on alternately. 

Some standard of reference was necesAory to give 
definite information of the effect of this new en- 
gine; and Savery introduced tbe term Aorte's powtr, 
which is still in very gtmcral use. A ceruin num- 
ber of horses were kept to raise a certain quantity 
of water to a certain height ; so a steam-engine, on 
Sttvery's construction, was called a one, or a two, 
or a tbret'. horse engine, as it raised the water which 
had hiUierto been ni&cd by one. or two, ur three 



350 



MAGAZINE OF SCIENCE. 



boTwi. ^'e b>ve no mtant of jadgiDg at the dita 
bo went on in his cnlculation of the pro]>ortions of 
the seTeral pirts of hii miohincs ; but from luine 
circutuflUnces, which we ihall afbcnrarda nuttce, it 
is extremely probable thai tlic; were constructed 
more from tict than calcaUtion. 
fT\t he emiimted.J 



OTRATIFIED NON-FOSSILIFEROUS OR 
PRIMARY ROCKS. 

{Rftumint /rttm pttgt^ 339.J 

Quorl: Rack. — Tliis ti a stratified rack the beds 
of which rary in diufnaious, the distinctions be- 
tween tbem beini; more strongly marked than ihoae 
of ^riss and mitvj schist, with which it is often 
associated. It la divided by natriral joiots, which 
cuuae it to break into rbntnboidal or rectangular 
fragmenfs. The variations in its mineral character 
are nurDerous ; its most siinide form is thus de- 
scribed by Dr. M'CuUoch : — " It is occHsionally, 
but rarely found in a compact state and crystaltioc 
throughout, little difTering from quartz, as it occurs 
in veins, but even in tliose cjises showing a constant 
tendency to divide in parallel beds. More fre- 
quently, when pure, it baa an aspect obscurely 
granular, which, by degrees, becomes somewhat lax 
and arenaceous, the grains varying In size and in 
the iutimacy of their aniuu. In some of the*e 
examples it appears to be a granulnr crystalline 
mass ; in others it possesses n mixed mechanical 
texture; while in a third, the rounded aspect of the 
grains, and the tm&U number of points of contact, 
appear to indicate on origin chiefly mechaoicfd, and 
rcK'.iltiiig Iruiii the ugijlutiimtion of sand. Cavities 
are sometimes found in the specimens containing 
rcj^ldr, though minute crystals of f|nartx." 

There are other varieties, consisting of quartx 
iuUtriuixcd with felspar, and tiuartz intermixed with 
mica, forming the passage into gneisa and mica 
schist, with both of which rocks it oltcmates, as 
also with argillaceous schist. The color uf quartz 
rock, when pure, is white, but it occurs of other 
•hadesi as ocbre-yellow, aud red. The presence of 
mica often produces a gref-colored rock, and a 
mixture of felspar communicates a fleih-rcd tint to 
this compound form of quartz rock. 

Arffiiiaceoua SchiMt. — This ia a schistose rock, 
consi»ting chiefly of indurated clay, varying in hard- 
ness, l^t-itility, and composition, and uiiiii^tin^uifth- 
able, except bypositiou, from the argiltaceues slates 
of the lower secondary series. Its es&ential mine- 
rals are the indurated clay which forms the whole of 
tlie simple varieties, and quortx and mica, which 
enter into the cowpouod varieties. The prevalent 
colors of the 6oer kinds are lead-blur, sometimes 
red .md purple, pray and yellow. The green varie- 
ties ountain chlorite, and pass into chlorite schist.. 

Crystalline, or Primary Limejftrme. — A remark- 
able peculiarity attending the primary strata consists 
in the lery small proportion which the calcareous 
rocks bear to the rest of the group, thus afi'ordiog 
a striking contrast to the secondary rocks, amoog 
which carbonate of lime is so largely developed. 

Primary limestone is a simple rock, varying from 
a highly cryataUiiie texture, both large and liue- 
grained. to compact. It is of various colors, but 
geocrallj white. The purest and whitest varieties, 
BOtnetinies called saccharine lime4tone, frum their 
rvs«mblance io small raaatics to sugar, ore muuU 
pri»od 9% stumary marble, and aw dcnvid chielly 
Uoiu the cclchrstcd quarries of Ciieccc and Italy. 



Tbu rock is generally met with in imolir Mi. 

alternating indifferently with " ">- — - t^M of 
the [trinmry icrie*. When in i :r U 

is olten indurated, and when ^ . n»e- 

times converted into a cherty sobstancr. When 
interstratified with gneiss or mica achisL it is afrtto 
acquire so much mica as not (o be e»«il) dij^o- 
gushed from those rocks on a laminar fracture. 

Tbo memberv of the primary strata vhich ocntr 
in the grratcst abundance, anJ in the Ufge»t masses, 
are gnn'ss and mica slate. The scries may thcrefoR 
be conveniently divided into tbe gneiu aud ink* 
schist systems. Tbe former, which is the lowral. 
consista of strata uf gneiss. micA schist, bomblMtds 
schist, quartz rock, primary limestonir, and srfLU 
laceous schist, ultemating in no certain order- la 
the juicM schist system, the most quarU<ii»^ sttd 
feUpathic portions are found towards the t>uttom of 
the system, the most argillaceooa portions u>«anls 
the upper part. Tbe Umestooe occurs imbedded t« 
the mica schist. 

The primary strata occupy a Urge poriiOB of lb* 
surface of the earth. There is scarcely a coaiUiy 
in any part of the world in which they are BM 
exposed to view, either by the original abaenoi ni 
the aeeondary series, or by tlieir dcundatkm Of 
disruption. 

Tbey are found in Scotland, Ireland, and part of 
Frojicc ; tliey occupy extensive tracts in Norway, 
Sweden, and the north of Htusia; they constinUa 
the central lines of the .\Jps. and other moujitxi»- 
rnngea ou the continent of Europe, having bcaa 
brought up from beneath the overlying strata by thf 
subterrunean forces which upheaved tbo«e chaini» 
They occur extenaively in the Uroxils, in tbe Uniiai 
States, and the remotest parte of America wbkJb 
have yet breu visiteil. %Ve know little of the go** 
logy of Africa, but they have been found there also. 
They constitute a large portion of the island eC 
Ceylon ; tbey enter extensively into the compoaW 
tion of tbe Himalaya Mountains, sod are by ■■ 
means rare in other parts uf the continent of AjU# 
l^ey ore indeed so extensively di!<tribuled. aail, 
wherever found, appear under such a gtutrol simi- 
larity of character, that we are justibrd in asiomiqg 
that tliey exist beneath the SMOtidary slrau In all 
parts of the world, and that ihcy have been pM» 
duced by some general cansea acting daring ifct 
period of their deposition over the whole glob** 
Tbe nature of thoiMs causes has afforded uaticf Ibr 
as much coQtrovrrsy as thu origin of the unstratiAei 
rocks. Werner maintained that tbvy wcro fi 
with the world, and wore a cfacmicii] deposit 
"11 chaotic fluid," which held their consti 
and those of granite io a state of ch> 
Aa Uic waters of this ocean gradii-! 
the minerals with which they were OiAr^fd, 
became capable of oupporttng animal life 
deposits ceasrd, crj-stalUne mcks were 
formed, and tbe secondary strata were drp 
exbibitiu); entirely a fragmentary stmctu 
containing the imbedded exuvise uf animata. 

Hutton, a Scotch philoaopber, contf m p>>rar} 
Werner, propounded a very diHVrent dootrina 
spccting tlie origin of the unstruiiticd rocks and 
primary strata, which has triuinpLrd over the 
hypothesiK, aud has been cntiiirmed, in its BoA 
important points, bythe obKrrHtir.n.^ ni ihr 
logists who succeeded him. lie 
geological phenomena aHurd cvidetu 
hing of things ; thai the olHrsi rucks w« i 
dciivativc, the ruiusof pfc-cxisiiue rocki 



MAGAZINE OF SCIENCE. 



361 



oiion of ntmoipberic agency, ond UiMt 
, borne by rivm to the ocean, and 
ted over its bed, became afterwards 
hf heat, »nd then aphfareil nnd frac* 
cryBtaUioe. or primary strata, accord- 
were, or^^oally, tnerbsntcal deposits 
le serondary rock*, bat altrred by the 
acttoa of Itent ; whilo granite had 
a state of fusion, aod had »lflwly 
it preuttre. In support of those 
hlB friends, Playfatr and Sir James 
much of that evidence which we 
adduced as proofs of the igneous 
UDfttratified rocks ; and be was him- 
|nt observer of reins ramifying from gra- 
the luperincumbeot strau. His delight 
Ipiog these phenomena cKhihitctl at the 
td the granite with the stratified rocks in 
•o great, that his guides supposed he 
a gold mine. 

(To be continued. J 



RTIPICIAL CONGELATIONS. 

tamwut d from pagv 34] . and cKHtfu^Mi. ; 
>apOTiBMnt» yet made known on frigorific 
wftttoat the aid of snow, are those of 
ker, of Oxford ; some of these are aa 



roag fnminf^ nitrous acid, diluted with 
or distilled water is best), in the pro* 
2 psrts in weight of the former to 1 of 
^ well muted and cooled to the temperature 
3 parts : of Glaaber's salts -1 parts ; of 
moaia 3^ parts.* each by weii;ht, and 
eparately to line powder. The Glauber's 
be first added to the diluted acid ; the 
ttioat then be well stirred, and the pow- 
tous ammonia is immediately to be intro- 
Irring the mixture again. The salts should 
ped as dry and transparent as possible, and 
ued newly powdered. 
are the best proportions, when the com- 
iperaturr is b^". Arcordmg us the tern- 
•t letting out, is higher or lower, the 
of diluted acid must be proportionabty 
d or increased. This mixture 'is little in- 
one made by dissolving snow in nitrous 
it tank tlie thrrmometer from 32^ to 2^", 
I all 52*^. In this experiment 4 psrts of 
Sd were used. 

liied nitrate of ammonia, reduced to very 

rier* suok the thermometer, during its 

raio water, from 56'^ to 8^ ; when evapo- 

ktly to dryness, and finely powdered, it 

tiiermometer to 49°. Mr. Walker has 

prodnced ice by a solution in water of 

llone, when the thermometer stood at 70°. 

■ml weight of mineral alkali, finely pow- 

t added to the mixture, the temperature 

irered lO"" or ll'* more. 

1 evident that artificial frigortfic mixturei 

plied to domestic purposes, in hot climates, 

7 where the inhabitants can learcely distin- 

jmmer from winter by the sense of feeling, 

lot be ami» to give a few hints respecting 

sat method of using them. 

»st cases, the foUowing cheap one may be 

t: — Take any quantity of strong vitriolic 

vdar osmpovcd of sal ainmoiUac b (Hirti. and tiitr* 
4»*(1 tagiUwr, nay bi tutMttiutfil foi ilw lUU-au 



add, diluted with an equal weight of water, and 
cooled to the temperature of the air, and add to it 
an equal weight of Glauber*s salt, in powder. T^ds 
is the proportiun when the temperatare, set out 
with, is 50 ; aod will sink the thermometer to 6°; 
if the temperature bo higher than 50^, the quantity 
of salt muHt be proportionally increased. 

The obvious ond best method of ascertaining tlie 
quantity of any salt necessary to produce the great- 
est effect by lolution. In any liquid, at any given 
temperature, b to odd the salt gradoaHy, till the 
thermometer ceases to sink, stirring the mixture all 
the time. If a more intense cold be required, 
double a(|ua-fortis, as it is called, may be used. 
Glauber's suit, in powder, added, will produce very 
nearly as much cold as when odded to diluted 
nitrous acid. A somewhat greater quantity of the 
salt is required. At the temperature of bif, about 
3 parts of the salt, to 2 of the acid, will sink 
the thermometer from that temperature to cearly 0'^; 
and the consequence of more salt being added is* 
that it retains the cold rather longer. This mixture 
has one great advantage in its favor ; it saves time 
and trouble. A little water in a pbial immersed in 
a tea-cup full of this mixture will be soon froxeop 
even in summer ; and if the salt be added In crya* 
tals, not pounded, to double aqua-fortis, though In 
a warm trmprraturr, the cold produced will be suffi- 
cient to freexe water or cream ; but if diluted with 
one-fifth of its weight of wster, and cooled, it will 
be nearly equal to the nitrons acid faefore-mentioaed, 
and will require the same proportion of the salt. 

A mixture of Glauber's salt and diluted nitrooa 
arid, sunk the thermometer from 70^, the tempera- 
ture of the air and ingre<Uents, to 10*^. The cold 
in any of these mixtures may be kept up a long 
time, by occasionally adding tlte ingredienta in the 
proportions indicated. 

Take equal parts of sal ammoniac and nitre, in 
powder; and cool them by immersing the vessel 
which contains them in pump-waler newly drawn, 
its temperature being generally 50". On 5 ounces 
of this powder pour 4 ounces of pump-water, at 
the above temperature, and stir the mixture; ite 
temperature will be reduced to W^, and conse- 
quently it will aoon freeze the contenta of anr small 
vessel immersed in it. The cold may be continually 
kept up and regulated for any period of time, by 
occasionally pouring off the clear saturated liquor, 
and adding morn water ; taking care to supply it 
constantly with aa much of the powder aa it can 
dissolve. Thu is a coavenieDt mixture, for if the 
solution be afterwards evoporated to dryness in an 
earthen vessel, and reduced to powder, it will answer 
the purpose as well as at first ; as \t% power does 
not aeem to be lessened by being repeatedly treated 
in this manner. 

All the ingredienta employed by Mr. Walker 
being taken at the temperature of 60^, the following 
table will exhibit the result of manyex|ierimrnts : — 

TcnoL 

*Sal BiDinoniac 5. nitre 5, natar IS parts lir . 

5, BitraS. Glaub«r'f ntta, watar 14 ........ 4 

*Mtrale oraniniaBia I, water I 4 

— ^ I. Boda 1, water 1 T 

tUlanbfr'taalt S. dltott niL sctd S 3 

—- ft. baI amiroiilar 4, nitre 8. dilute nit acid 4 . , 10 

6. attrat« of ammooia S. diluW all acid \ .... \A 

Phfupliunled toda 9. diJuls lUt. acid A 18 

». nttrate orammon. 6, dilute nit. acid i .. . 21 

Hilaaber'a isll S, marine add 6 

T — y auut« vuttwUc acid 4 



MAGAJ 



i¥ SCliiNCK. 



Tht vdtn marked thus (*) may he recorered bj 
cvmporatiog the mixture, anil msy be uied a^tn 
rvpeaferll;; tlione marked thu« (f) may be recovered 
for ute bjr diBCillatioa and crysttllization : the dilute 
nit. acid was red fuming nitrous odd 2 parta, rain- 
water 1 part: the dilute vit. acid waa strong Titriolic 
acid and raia-irater, equal parts. 

By a judirioiiii management, frigorific mixtures, 
with the aid of anow or pounded ice, mcrcnrj rrcn 
may be frozen into a iiolid maiui. Mr. Walker im- 
meracd a half>pint glofit tumbler containing equal 
parts of vitriolic acid, the specific gravity of which 
waa 1'559C, and strong fuming mtrouii acid, in 
mixtures of nitroua acid and anow. until the mixed 
adds in the tnmbler were reduced to — 30" : he then 
gradually added snow, which bad beeu alao pre- 
riously cooled la a frigorific mixture to — 15°, to 
the mixture in the tumbler, aUrring the whole, aod 
(band, after some minuteR, that the mercury in a 
thermometer immersed iu the fluid had become 
congealed or frozen. 

Quicksilver may be congealed by lulding newly- 
fallen enow to strong fuming nirrouji acid, preriooaly 
Goded to between —^j* and —HO", which may be 
easily and speedily effected by immersing the Teasel 
containing tho acid in a mixture of snow and nitroos 
add. 

But the moat powerful frigori6c mixture yet dis- 
covered, is produced by equal parts of muriate of 
lime and snow. An account of a Tery remarkable 
experiment of this kind ts given iu " Tilloch's 
Philosophical Magaxlne," Vol. HI. It wus per- 
formed by Measrs. Pepys and Allen. Into a mix- 
tare of equal parts of muriate of lime at 33°, and 
■now at 32°, a bladder containing no less than 5G 
poonds of mercury was immersed, after the mixture 
had Iiqiie6ed by stirring, and when its temperature 
was found to be— 42*^ ; os soon as the cold mixture 
had deprived the mercury of so much of its heat that 
its own temperature was raised from— 12'' to -f- 5°, 
the mercury was taken from it, and put into another 
fresh mixture, the same in every respect as the first. 
In the mean lime, the muriate of lime was kept cool- 
tog, by immersing the vessel which contained it into 
a mixture of the same ingredients : 5 pounds of the 
nnriste were, bj these means, reduced to— 1ft''; a 
mixture being made of this muriate and anow, at 
tho temperature of Z'i''', in the course of throe 
minatcs it gave a temperature of — G2°, or 94° below 
the freezing point of water. 

The mercury reduced to— 30° by immersion in 
the second mixture, and suspended in a net, was 
put into the new-made mixture, and the whole waa 
covered with a clorh to inipedr the passage of heat 
from the surrounding atmosphere. AfVcr an hour 
and forty minutes, the 5G pounds of mercury were 
found solid and fixed, llie temperature of the 
mixture, at this time, was — 4 6°; that is 16'' higher 
than when the mer cary was pnt into it. 

Several of those who were present at this ejtperi- 
raent liaving, without attending to the consequences, 
taken pieces of the frusen mercury into their hands, 
experienced a painful sensation, which they could 
compare to nothing but that produced by a bom or 
scald, or by a wound intlictH with a rough-edged 
instrument. The parts of Che band which were in 
contact with the metal lost all sensation, and became 
white, and to appearance dead : a phenomenon 
which alarmed the sufferers not a little : however, 
toon throwing away the pieces from therti, as they 



would hare done hot coals, tlie injoryi 
trated the skin ; and in a little time 
friction, resunied their usual aensatioo 

The Ute Profcuor Leslie devised 
method of reducing the temperature 
low lo freeze water in any climate, and 
son of the year. His method is shortly tl 
the receiver of an air-pump, place one ▼■! 
taining sulphuric acid, and another contdi 
small quantity of water. The air being partj 
drnwn from the receiver by the air-pomp, a 
raised abundantly from the water, and al 
the acid. Thus a degree of cold is prodl 
freeiM the water in a very nhnrt time. 

A saucer of porous earthenware is 
for holding the water, and instead of sul| 
other absorbents may be used, such aa pi 
meal, the powder of mouldering whinat 
dry powder of pipe-clay. 

Mr. Leslie placed a hemiipherical vi 
earthenware, containing a pound and 
water, over n body of parched oatmeal, 
diameter aud one inch deep ; and by 
pump for some time, the whole of the ' 
froxen. 



(ToAa Sditor.) 

Sir. — Having made some experinnenta 
of discovering a cheap and good bronxe 
type medals, and having been fortunate cmi 
hit upon a process which produces one like t 
am bronze, I forward it to yoa, reqoesting j 
be pleased to insert it in your Magaxino 
benefit of those engaged in electrc 

Thoroughly clean the medal and 
make a thick paste with urn powder and 
apply this with a brush equally over the i 
the medal. \Mien dry, place it over a 
the kitchen fire-shovel for about a minni 
less, according to tlie depth of shade reqi 
when coot, polish with a plate brush. 

The um powder may be bought al 
polishing powder manofecturers. 

Common rust of iron may be substitut 
urn powder, it produces a similar 
of a different shade. bj 

Jiuuiarg u. lao. 



iTo th0 Editor,) 
Sib. — Since reading in your excelleDt Mi 
account of Mr. Wagitaff's air-pump, 
plan has occurred to me, which I think 
improvement on his, via. : — 

To place the eyUoder horizontally, 
taps or valves, one at each end of the c|j 
to make the piston-rod work through a 

The advantages of this arrangemeiit 
that air would be extracted at each 
piston, and the machine itself would 
room. The valves may be opened and 
proper moment by any one of the variou. 
tnvances used in moderti ttteam-«iigin« 
purpose. 

If you conndcr this suggesdon worthy' 
] shsll feel honored by your iiiscrtiog 
Magszioe. 

Jjomgport. SiimtrtetMhin, 
fama/y\9. IMS. 



LowOM.— PrlBtfd by U. Fkawcib, A. Wtiitc Hone Lan*. Mil* Ea4-— fuhltih^d by tv. ffntTTAiM. II. ^sUrvt 
CenmaalcaUMu, (wbicli ar« aoawmd MonUily.j lo tw addrrMcd t« tti» Editor, si S3. Cotugv Crorv, 




MAGAZINE OF SCIENCE 



THR 



^ntn Retool of ^m. 



149.] 



SATURDAY. rKBRUARY A. 1841 



[lirf. 




3r>4 



MAGAZINE OF SCIENCE. 



Tt'tf^rajfhic Railwai/t : or, tht Single UViy.- rf- 

mmminiteii btf Stifett/, EefmoMy, amJ ICJ^cifnc}/, 

wnifr-r yAff Sofvguard ami Omtrnl (^ the J^lectric 

Trlegrnph. lit/ H^ F, Cooke, fi#j.— (Simpkin 

nnd MarshiillO 

A t.tm.K varU nnilcr iho sbove title hu just rande 

i(» ii|tpmrfliHtp, nu(l when we mrnliiHi Uint tfji autlior 

M tlie »a:iic Mr. Cooke, who was (he condjutor o( 

rrofeuor ^VheBtsConQ in the invtrntinn nnd esta- 

lihvlime'nt nf the electrical trlr^rnpli, it will be suffi- 

cifinl tn enll altcnlion to his work. 

Tliu nuthor statci that he swlia two objects : — the 
1ir»t id to odd to the tufrix and efficiency of railwaj 
communiraUun, bj meaii!*, not more, but lew ex- 
pensive than thoie now adopted. The second ia, to 
uvercomo some objections to the furmatitin of 
auxiliary single lines, by ungi^rstiuna calculated to 
ip*e llwm the snfety mid cHiiicncy now iiU|>j)0Sed to 
be cicltiaively wiiliin ihc nrarh of drmble liiiea. He 
propo»r» to ocrompluh ibcse oljjeulii hy the eirctric 
trlegrttfih, thr object of which is clearly eipUined 
in tlifi subjoined fltntement. The first of the«c 
|K)iiits, wbetlier a 9in;;)e line of rnilway would hf' 
equally safe, rapid, and efficient to the double rail 
now established, wo will not prf?tfn;l to olfer an 
opinion U|N)ii, not beiiif; an engineer ; but the 
pccnliar ndvantageg of the electric telegraph in 
conveying inrormation along a line wiUi iii»Uiuta. 
nenua ntpiility, is certainly within the legitimate 
obJLftj of science, snd one which we are very happy 
to illustrate; indeed, wr had prepared an article 
upon it, but which we willingly cancel in order that 
it« orlLiinator may bimself exhibit its advantages. 
Tbf fulluiKiiig is an extract from this vuloable and 
originid work : — 

" In contiderini; the electric telegraph as a most 
drairable, if not indispensable guardian of railway 
traTclling on an eitendcd scale, I am borne out by 
the opinions of many of the first practical men 
cosnixant of the subject—by the successful experi- 
nitntal nppUcatioo of the telegraph to a part of the 
lirvat Western railway — the judgment of a I'arlia- 
mentory Committee — and the hourly experience of 
that most masterly work, the Blackwall railwiij. 

" It is well known that on the Dlackwall railway 
the carriages on each line ore moved by what is 
called * a tail-rope,' to which they arc attached, 
nnd which is almost incessantly being drawn along 
the line, to be wound up on n drum at one terminus 
or thi' other, by the alternate action of the stationury 
engines. It is consequently necvssary that, before 
the eoeine-man applies the power of his engine to 
the rope for the purpose of giving motion toa train, 
he should have received a specific intimation from 
every other station that its earriac^e Is attached to 
the rope, and ready to start : otherwise an inde- 
|iendent and uncontrolled motive power, acting from 
the terminus, would fre<piently cautie dreadful col- 
luiouK among carritiges placed at stations so nearly 
adjacent as tJiose at Shadwell, Stepney, Limehouse, 
the West India Docks, and Poplar. 

** It is also necessary that the moit perfect an- 
dernlanding ihonld exist between the breaksman at 
one tcrmmus, and the eogineman at the other, na a 
very skilful adjustment of the quantity of rope 
relta-f(l is rc'iuisite to preserve the rope from injury. 
In a word, the condition of starting a train is, that 
the telegraph at the terminus to which it is going 
alio'jtd express that the carnngra at the six olhex 
sULiuns are ready; and 6naUy, llut tlic brvaksmBn 
at the Btarting tenaiuus, (oa whose ajgual, in fact, 



the stortiog de]iends,) is ready nlan. The operation 
of stopping Is still more delicate in ita ehon^v 
and e«inHe({Qenci!B ; for, if the engine-man were to 
tnm ciH* his steam before the breaksman at iht 
other terminus had begun to apply his brrak, tha 
rope n>u9t suffer from overslnc knees ; or. if tbi 
breakgroiitt were to put on bis break whUethtm- 
f;tiiL> at the distant term'mus was still exerting ill 
ftill power, it might be broken hf Uie etcrwivs 
strain. Even the ordinnry stoppinf of ■ tnia 
could nut be etrected wiilmat danger to the rope; 
and an unexpericd stuppa^ (tmw a matter of anK- 
nary occurrence and perfect liicility, ewm at hU 
speed) would, without a telegraph, be attended vllk 
certain injury. 

** (>n a niilwiy which despatches « srrieo of 
trains in each direction every ifuartfr of nn bovr, 
and has stations within a few hundreil ^rda of esiii 
other, (not nicatn tu dwell upon thr rirrumslanec af 
a distant nnd independent motive power, ] accktcaul 
derangement would be more aerious in its oon*^ 
qnences, and of more frcijnent occarrence, \i not 
prevented by tlie telegmpk, than on any ordinary 
tine. Now, in |K)int of fact, milliooi of paeuu-DKtrs 
have been carried in safety upon the Blackwall rail- 
way, during the 16 months which have ptnrd alaee 

the hue opeited, in upwards of half • m-" "» 

carriaees, startini; and stopping indepr: 
each other ; and this through the intervo. 
system of telegraphs, commanding only from two 
to eight signals each, and worked hy Uids, or portsn. 
ur breakKmen, performing regnlarty their ordnnvj 
dutirs. 

** Here, then, the electric telegraph nay be lara 
in daily operation, with the most beneficial effFtti. 
If sn accident occur, the telegraph renders it ham- 
less : a carriage, perhaps, loi<ei its * grip* of Ar 
rope, and gives a signal of distress ; the i>Ofler 
the nearest station transmits a telegraphic oi 
stop the engine working that Une ; and 
or three minutes the knun is again in motion 
oat alarm to the panoigert, or interferetKc 
working of the other tine. By enabling 
distant stations to converse with the speed 
of lightning, it substitutes a known certainty 
inferential probability of safety, or danger. 

** To a system so nicely adjusted, but liobls ta 
such sudden interferences, as that of the BUdlrvil 
railway, the best time-table would be rvidentif 
applicable. If. then, under circumstances of 
extraordinary difficulty and complication, the 
trie telegraph, in the hands of ordinory worl 
performs its duties in the most perfect ai 
is a necessury consequence, that it is ea 
dispensing its benefits with equal certainty 
thuse duties would be uicompsrably leas arduous, 

•• The principles on which the electric le, 
is cooiitnicted, ore founded on Ot-rstcd's ctXt 
discovery, that a magnetic or compass need^ 
through the agency of a voltaic current, be 
with an artificial pokrity. Thus, as a 
stream of electricity, jmasiaK nxuid the 
ferencfl of the earth, causes magnetic n< 
general to be deflected at right angles b> I 
or towards the north and sontli polcw ; wo *m 
ficinl stream of electricity. ■ f 
will cause iringnctic ncedle^, 
flnence, to he aimitarly detlecii.>; a-. >:k'>< »<^ 
iU oourse, whatever that may be. If, tlicn, 
netic needle were placed parallel , and neir 
part of a conducting wire, which we will 
to bo Liid down bclwecu Iioadon and 



MAGA2INE OF SCIENCE. 



356 



RBinion of aa electric current from a vol* 
try wouU cittM the needle to cbiui^^e iti 
•o as to stand, during the conUniunce of 
tot, at nghl aasles to the wirei being 
i one direction or the other nncortling to 
e of the eurrent. If this deflexion of the 
trc litiiiicd by two (ued itopi, placed re- 
r At the two sides of one of its polei. the 
t that pole to one stop might ertdently 
t OM i%nal, and its motion to the olbtr 
ftcr signal. 

I represents some of the BlsckwsU rail* 
niments, constructul upon the principles 
pUined. The signals are ^ivf^n by pointers, 
^drJ vfrtically ou an axis, mOTiog freely 
Kbc face of a dul. Itchind titc dial a mag- 
■d on the same axis as the pointer, so that 
IB together, as is seen in Fig. 2, where A B 
Mgset and pointer ; C C the conducting 
the coil; and the galvanic battery. A 
f the condncting wire is coiled mtuiy times 
"y round a frame in vhicb the magnet 
as to subject the magnet to the mulU- 
g force of the voluic current. The 
the magnet is limited at both sides by 
|M. Now, suppose three of these very 
Mtmments, included io the same conduct- 
te be placed, one at the Minoricii, a second 
jiraU, and the other at some Uiird point. 
enl effect of this arrangement would he, 
itnLnsraissiua of electricity along the con- 
IVire, and therefore through the convolutiuns 
iBrroundirig the rt^apcccive mofcnets, vould 
j^se Qiai^iicts with a sudden and decided 
ta one of the stops, and c^u»c the csterior 
tCo indicate corresponding and simuUancoLis 

Kn the dials of the three instruments. 
loent is provided with a battery ; and a 
ky which a porter or policeman is enabled 
In to connect the conducting wire with his 
■ Bj flooring the handle to the right or left, 
' Im aigoals can be instantaneously trans- 
roiB anyone of the iastrnmenla to all tlie 
iwhioh, by means of their own handles, 
I power of sending back signals in reply : 
n b^g ensured by the simultaneous ap- 
i>of tbe signal in the instroment of the 
and that of the recipient. The trsns- 
f intelligence is prefaced by sounding a 
teotion i^ obtained ; an operation clfeclcd 
agency of the voltaic current." [The 
thia was described in Vol. I. — kd.] 
3 represents one of the instruments upon 
orgh and Glasgow Railway, being a com. 
jpf (wo of the above rlcmcntary telegraphs. 
Idle ia here worked by its distinct hdudle. 
bglo movements of the pointers, tlio figures 
fend b, may be given. If the two pointers 
f to converge upwards at the same time, 
pabioed indication will be the figure 1 ; or 
bonverge downwards, 8. If the pointers 
I to rest diagonally parallel to each other in 
itioD. C, in the other, 7 ia indicated. Eight 
iKgnals arc thus obtained, which, in oon- 
Ith a code, ara suflicient for all ordinary 
. By combining seTeral elementary telc- 
Uf number of signals may be obtained. A 
^ tbe telegraph employed on the (treat 
railway, worked by keys, and having a 
farrongeinrnt of the candurtinir wirrii nuL 
IT to be t-ipUincd, ia aubjuined to illu^tratr 
[Thu ia represuutcd in Fig. 1.— en.] 



** The appantoB which ] arranged upon the Great 
Weatem railway enabled me to submit the electric 
telegraph to the test of experience to the ejicnt of 
78 miles of wire, equal to a stage of 39 mileii, nor 
did I see any reason to doubt its capability of 
working for much greater distances, without inter' 
mediate stations. Ttie scientific iuveatigalioni uf 
my coadjutor. Professor Wheatstone, tend to the 
^ame conclusion; and I may observe, though not 
to my present jmrpose, that our latest iniprnvc- 
racnts have enabled ua to carry on tbe moatcoui- 
plete and extensive correspondence with only two 
or three wirea." 

After the author has thus described his very in- 
genious instrument, he proceeds to give his pbin 
for a telegraph railway, and to illustrate its efliciency 
under the nnusual drcumsliinccs of an express trsin. 
The impediment of ballast waggons — of pennanent 
obstructions — and crossing of two trains — nnd very 
numerous other important matters, which, nlthongh 
of the 6rst importance to the general aubject, it 
would be irrelevant for ua to inlroducc. \V*e trost. 
however, that this slight notice will induce inquiry 
for a book, which, small as it ia, contains much that 
is original and valoable. 

OBTAINING IRIDIUM AND OSMIUM. 
Thb black pulverulent residue which remains after 
the Bolution of native platinum in aqua regia, con- 
tains, besides the combination of osmium and 
iridium, a considerable quantity of free iridium, 
and aome iron and titanium. Wbhicr recommends the 
following process for separating them :— Mi\ equal 
portions of thr residue and decrepitated common 
salt, and pince tliem in a green glass tube, which is 
tu bo passed through a tube furnace similiir to that 
in the apparatus of Liebig. To one end is fixed an 
apparatus for the production of chlorine, and the 
other commuiiicslfs with a vessel filled with am- 
monii, preceded by a bulb fur thcabsorplion of tbe 
oxide of osmium. Under the tube IiQt coals are to 
be pldt-ed, in order that the mixture conlaint--d in it, 
which should occupy three-fourths of its diaateter, 
msy be exposed to a strong heat. Tlie chlorine ia 
then allowed to paas through the tube. By this 
operation sodium -chloride of iridium, and sodium* 
chlonde of osmium air formed, both of whit;h salts 
are soluble in water, while the titanium remains in- 
soluble. A little chloride of osmium will be formed 
in the first porLiun of the tube. The greater por- 
tion of the oxide of osmium will have crystallized 
in the bnib situated at the rxticmity of the tube. 
The bulb ii to be exposed to a heat ao oa to melt 
the oxide, and in this state it may be poured into a 
flask or glass tube. The tube may be placed on 
one fide, so as to allow the oxides to sublime in the 
form of long crystals on the opposite aide. 

To the ammonia, which contains more or less 
oxide of osmium, and is colored yellow by it, let 
some sal-ammoniac and carbonate of soda be added, 
and let the whole be then evaporated to dryness, 
and heated to redness in a glass retort. By this 
method tbe oxide will be reduced to tltc mrUilhc 
state, which, by treating with water, will remain in 
the form of a bbck powder. It is tlien washuil 
and dried. The oiide in the bulb may be reduced 
in the same manner after it has been dissolved iu 
ammonia. 

When the tube with its contents is placed in a 
cylindrical vessel full of water, all the soluble por- 
tion di&itflves. A deep browuiah red aulution of 



1 



356 



MAGAZINE OF SCIENCE. 



double ftalt uf iridiutn is formed. The liqaid afWr 
sUncling should be decanted from tho midoc, which 
conrista of tiuoiam, and some pieces of otminm and 
iriJiuni. The fluid drawn off U distilled to tep«- 
rate the oxide of oamiam, which majr stiU exist in 
it. When the whole of the add bu jiused orer, 
the distilUtioD is stopped And the solotion filtered. 
It is then to be emponted orer a fire, and during 
the concentmtian, carbonate of BO<la is be added in 
excess, which throws down a blueiith blsck prc- 
cipilBte. 

The dried black msss will then be itronglj heated 
in a Hessian crucihlc, and sftcr coolinj^, be digested 
in wuter. The residue Is a sesqoioxtde of iridiam. 
'i*he filtered salt solution conCaiiu, besides common 
aali and carbonate of soda, also chromate of soda, 
which gives it a yellow color. 

Tlic scjrqnioxide of iridium contains, besides 
osmituD, some oxide of iron. It is to be placed in 
a glau tube, and hjdrogen passed orer it at a red 
hfM till water ceases to be formed. Metallic 
iridium thus obtained is a black powder. It con- 
tains much caustic sada, which was cUemicslly com- 
binrd with scsquicixide, and iit now taken up hy 
water, hy digestion in muriatic acid the iron is 
removed. After washing, it may be placed between 
layers of Altering paper, and pressed fur several 
houri with a Bcrew press. Hfatcd then in a cruci- 
ble, it iii obtained in the. form of n firm potixhed 
grpy mass. Metallic iridium may be obtained by a 
shorter method, but not in such purity; by eva- 
porating the solution of sodium -chloride of iridium 
to dryness, boating to redness, so as to melt the 
aalt, nod begio to volatilize the diloride of sodium. 
The iridium will thus be reduced, and remain, 
nfter dlgcation in water, as a grey or bluck metallic 
jiowder. 



SPEAKING AND HEARING TRUMPETS. 
As the sight is assisted by telescopes and micro- 
scopes, so simitar instruments have been contrived 
for assisting the faculty of hearing. One of these, 
called the speaking trumpet, is employed fur con- 
veying aound to a great distance : the other, called 
the rnr-truntpct, serves to magnify to the ear the 
least whisper. 

Among the modt?nis, Sir Thomas Moreland be- 
fituwed the most labor in endeavouring to improve 
this mrtliud uf enUrgine and conveying sound, and 
on this snlijcftt he published a treatise, entitled 
" Du Tuba Stuutortipliunica,*' a name which alludes 
In the voice of Sleutor, celfbrated iimong the 
Greeks for ila extraordinary etrcogth. The follow- 
ing ohsKTvatiDtiK on this subject ore in part borrowed 
from that curious work. 

Tlie luicients, it would seem, were acquainted 
with the speaking trumpet : for we are told that 
Alexander liad a born, by mtans of which he couM 
give orders to his wliole army, however numerous. 
Kirchcr. on the nuthorit/ of ■omo passages in a 
monuscript, preserved in the Vatican, makes the 
diameter of its greatest aperture to have been seven 
feet and a half. Of its length he says nothing ; 
nnd otdy adds that it could be beard at the distance 
of 500 fttadia, or about 25 miles. 

This account is no doubt exaggerated ; but, how. 
ever this may be, the .speaking trumpet la nothing 
else than a long lubp, which at one end is only Urge 
enough til receive tlie titouLli, and which g«i« on 
increoaing in width to ilu- other extremity, bending 
outwaida. Ttie aperture at the amall cud 



most b« a little flattflied to fit the month ; and II 
ought to have two lateral projections to oorer part 
of the checks. 

Sir Thomas Moreland says, that he caused arvrral 
inatrumenti of this kind tn be constracted of dif- 
ferent riies, viz. one of 4} feet in length, by whM 
the voice could be heard at the disUnce of S>M 
geometrical parea ; another IG feet 8 inchea. wMiA 
conveyed sound 1800 paces ; and a third of 24 fert, 
which rendered the voice audible at tlic diftiancc of 
2500 paces. 

To explain this effrat, we shall not ny, vStli 
Oxanam, that tubes serve, in general, to ttrengtlusi 
the activity of natural causes ; tliat the longer clivy 
are the more this energy is increased, &c. ; for this 
is not speaking like a philosopher ; it is taking the 
effect for the cause : we most reason with mora 
precision. The cause of this phenomenon ti aa 
follows : — 

As the air is an elastic fluid, to that every sound 
produced in it is transmitted spherically around the 
sonorous body ; when a person speaks at tbe moulli 
of the trumpet, all the motion which would be cum* 
monicated to a spherical mass of air, of 4 feK 
radius for example, is communicated only to a 
cylinder, or rather cone of air, the base of which Is 
the wider end of the trumpet. Conseqaently. if 
this cone is only tbe hundredth part of the whole 
sphere of the same radios, the effect will he. ni great 
as if the person should speak a hundred times as 
loud in the open air ; the voice roust therefore bt 
heard at a distance a hundred times as great. 

The ear trumpet, on instrameot cxoeedtiifly 
useful to those almost deaf, is nearly the revenr or 
the speaking trumpet; it collects, In the ■uditory 
passage, all the sound contxioed within it ; or tt 
increases the sound produced at its extremity, in s 
ratio which may be said to be as that of tbe vlilr 
end to the narrow one. Thus, for example, if tfaa 
wide end be 6 inches in diameter, and the apertartf 
applied to the ear 6 lines, which in surfaces gireft 
the ratio of 1 to Mi, the suund will be incrowd 
1 4 -I times, or nearly so ; for we do not believe Ihsl 
this increase is exactly in the inverse ratio of lln 
surfaces ; and it must be allowed that, in this 
respect, acoofttics are not so far advanced ms optica. 

ilke lube of the car trumpet is now often moils 
of India-rubber, covered with an oniamental ucf. 
work. It is made of considerable length, and being 
flexible, the wearer can converse with a |»«rwa 
acrofls a tabic by passing over the end to which the 
mouth-piece Is attached, and applying the other 
to his ear. 

It is a certain fact, proved by exprrifMir^v 
ever may be the cause, that Bonn<i 
tube, is conveyed to a much grentcr 
in the open air. Father Kircher relates, m 
of his works, that the laborers employed In 
subterranean aqueducts of Rome, htard each 
at the difit«nc« of several miles. 

If a person speak, even with a very If"- •"''* 
at the extremity of a tube, some inchc* in <i 
another, who has his ear at tlie extremity, t. . 
distinctly what is said, whatever be the nuinber ot 
the circumvolntions of the Cube. 

This observation is the principle of a ma 
which excites great surprise in those unacqi 
with the phenomena of sound. A bust is p 
upon a table ; from tme or each of its ears a tube tt 
conveyed through the table anil one of its ffrt. 
as to pass through tht; floor. Nud to end in a Ui»r^ 
ur lateral apartmeut. Another tube, proce^i 



MAGAZINE OF SCIENCE. 



357 



nonUi, is conveyed in a «miUr manoer, 
me apartment. A person in company is 
i ask the figore anj question, by whisper- 
Sti ear. A confederate of tbe one who 
maicbine, by applying his ear to the 
of the first tube, bears very plainly whnt 
■id ; and placing his mouth at the ap«r- 
le other tube, retoms an answer, which ia 
the person who proposod it. If motion 
inicated nt tht^ same time to tho lips of 
Be, by any mechanical means, the ignorant 
nch surprised, and incliued tu believe that 
nou is the effect of magic. It may be 
If fcowever. that the caase is very simple. 



TAR AND PITCH. 
^ is ao extensiTcly used for naval par- 
be rUssed with the impnre empyreu- 
It is distillctl from the wood of tbe 
nd produced in large (|aantitics in the 
Cttrope and in North Aiucrica. We re- 
om Rusjiia, Sweden, and America ; that 
m Swedt-n being considered the best, and 
ig the hiifbest price. 

»art of that which is manufactured in 
I made from old fir-trees, which have 
n in the wootU, and have their sap no 
I. This is what is called light-wood, not 
itcv to its weight* as it is very heavy, but 
ombustiblc nature, readily igniting and 
jth lo bright a tlamc as to serve the office 
e. Only one partirular species of pine 
tluMtrit) become light- wood. Persons 
la making tar immediatrly know it from 
koce of the concrete juice in the grain of 
When fir-trees are to be cat down for 
those are most esteemed whoso 
re distorted and full of knots i the sap 
ereby retarded in its circulatioa deposit- 
d. as well as a greater quantity of 
r from which tar is distilled. Old 
which have remained in the ground 
after their brariuhes have been cut off, 
rich in that material. Itut the surest 
thod of obtaining the greatest quantity 
t n to strip off the bark and branches 
from such firs as are destined fur this 
to leave them in thai state until the 
mng. They sliould then be felled, and 
all pieces as if for fagots. Being well 
•a billets which appear most oily and 
re separated from the rest and alone rc- 
Bae; two-thirds or more of the tree will 
lained, provided it was in a state of pro- 
ty previously to the strippinjg of the 
that after this operation it had been left 

Rlong in the ground. This is called tar- 
e wood of the trees from which turpen- 
■ased to ilow is likewise made to yield tar. 
(Over which the juice has flowed and pnr- 
' are split on", and from these is made 
green tor, because distilled from gieen 
■d oif dry. 

aufficient quantity of wood is collected, 
marked out on the ground for the kiln. 
is then dug out a spade deep, sloping 
mire to the circumfereuce, and is thrown 
I a bank round the circle. A straight 
ifAcicnt length to reach from the centre 
beyond the buuk, is split lougitudinftlly 
red out. The parts are then put togctlier 




again aud one end is placed in tlie centre, being to 
supported on the ground that this end is higher 
than that which comes without tbe bank, where ■ 
hole is dug into the ground, into whirh the tar flows 
from the channel, and whence it is from time to time 
taken out and barrelled for market without any 
farther preparation. 

^fter the kiln is marked out, tho wood, being split 
up in small billuts, is packed as close as possihiet 
with the inwrird ends sloping towards tho middle, 
which is filled up with smaller pieces, consisting of 
the knots of the trees, these yieldiog more tar tlian 
any oilier part of the wood. The kiln is boilt in 
such a manner, that at twelve or fonrtecD feet high 
it will overhang two or throe feet, and appear quite 
compact and solid. After the whole of the wood ia 
piled, a number of small logs are placed round it, 
then a layer of turf, and so on alternately through- 
out the whole height ; tbe top is then covered over 
with two or three layers of torf. After the whole 
is thus arranged, a turf is taken out in ten or twelve 
different places round the top, at each of which 
parts fire is applied, and tlie pile then hams down- 
wards, till the whole of tbe tar is distilled from it. 
If oombustioii proceeds tiw rapidly, some of the 
holes must be stopped up, — if too slowly, others 
slioald be opened ; practice enables a tar-burner to 
judge with tolerable nccuracy as to the best mea- 
Borcs to be pursued in this respect. Six or eight 
days are generally required to complete the burning 
of a tor-kiln of the dimeosions here described. 

Another method pursued is to place the tar-wood 
in a receptttclii inclosed by an arch and walls, a small 
opening only being left near the bottom for the 
egrets of the tar : a fire is then made round the areh 
in such a manner tiist tbe heat may comrouaicate 
to the inside, and cause the tor to be distilled from 
the wood in the same way as if retorts had been used* 
This plan is perhaps more expensive tlian tbe first, 
and therefore less generally practised ; the operation 
is, however, performed in much less time, and the 
quatitily of t.ir produced from a given qusntity of 
wood is greater than that obtained by the other 
method, while a very superior kind of charcoal ia 
at the same time afforded from tlie wood tiius car- 
bonized. In the common way a cube of six feet of 
tar-wood yields from two to three, and sometimes 
four tuns of tar : burnt by this last deKribed 
method, the same bulk of wood produces, in half 
the time, five or six tnns. An equal quantity of 
common fir-wood yieldd only about one tun, or cue 
tun and a half. 

In Norway, and other countries bordering on (be 
Baltic sea, where the vast extent of their pme forests 
induces the natives to be less economical in the use 
of the wood, stacks of it are built on tlie slope of 
a hilt, and covered with moss and turf: fires ore 
then kindled in different ports ; and the tar which 
oozcB out flows through chonocla or spouts into 
barrels placed for the purpose at the bottom of the 
hiU. 

A more economical process for making tar is 
pursued in France and Switxerland, by which the 
wood is charred more equably, and the product is of 
a much more uniform, and probably also of a better 
quality, lo the V^olois tbe pines are felled the pre- 
ceding year, that the wood may be surficicntly dry 
for use ; and the outer bark and twigs being strip- 
ped off, the rest of tbe tree is cut np into billets of 
tolerably equal sixe. An oven u built of stone or 
brick in the form of an egg standing on its small 
end. On one side, about five inches from the 



958 



MAGAZtXK OF SCIENCE. 



lowest point, an apertare ia mnAt into nliirh a tube 
is iuerted. A Uri^o irua gmttng is laid at tbo 
IxttCom jnst xbove lh«) opening for tKo tube, and on 
lliit the billete of wood are piled. This grating 
prevcuts the puiiage of any pieces of wood or oUier 
iiOpuriUei, which wuntd iithcrwise run out together 
and mil with the tor. The oven beitig filled with 
wood, a Uycr of dry chips is placed at the top, ^nd 
the whole is inclotied, Icavtog only an spertore at 
the summit to act as a chimuey : the cliips are then 
kindled, aiid when the Are bus spread downwards, 
and the whole is sufficiently ignited, the chimney is 
enttrtfly closed with a large stone, and wet earth is 
heaped on Uus, more being thrown on wbeoerer 
the smoke burats out too stroDgly. The general 
Bvemgo product thus obtained is about ten or 
twelve per cent, of the weight of the whole chnrge. 

The common method, as pursued in the north of 
Europe, though the least e^pcnslTe of sll, is at- 
tended, however, with great tnconvmiences. The 
management of the fire is eitremcly difficult sod 
prccarioDS, so that scarcely any workmen, who have 
Dot been long lued to conducting the processr can 
be safely trusted with its snperinteodeucB, and the 
BOGcess ereii of these does not alwats answer their 
cxpeutatioD. A much smaller qnsutity of tar is 
always extracted in this manner than Umt produced 
from an equal qoauuty of wood didtillr^d in furnaces. 
The process by furnace ti therefore always preferred 
by those tar^bomers who have the means of par- 
suing it. 

t'itch, which is condensed tar, U obtained either 
by evaporation or burning. The process of burn- 
ing is performed very simply. A hole is dujf in the 
ground und lined with brick : it ia tlieo filled with 
tar, which is ignited and allowed to bum till the 
pitch is judged to be of safGcienlcousisteucy, which 
is ascertained by dipping a stick in it, and allowing 
the pitch adhering to it to cool. When lutficiently 
burnt, tlic hole contaioing the pitch is closely 
eovered, and the atmospheric air being thus ex- 
cluded, combustion ceases. Five barrcU of green 
tar are thus concentrated to two barrdi of pitch, 
and two barrels of other tur mnke one of pitch. 

When pitch is evaporated in kettles it requires to 
be almost constantly stirred. The country people 
in Sweden, when they have no kettle for boiling 
their tar, in order to reduce it to pitch, put it into 
great wooden pails ; into these paita they throw 
very large stones previously heated ; the stones ke<;p 
the tar almost boiling, sod thi« procees is continued 
until the fluid is of suSicient thicltnets. 

A {Kirtion of the tar imported into this country 
is converted into pitch ; the esUblishments for this 
purpose near London are conducted on a much 
more economical plan tlian that pursued abroad. 
Ilrrc n<i part of the tar which haa any useful pro- 
perty is allowed to be waxted. It is evaporated in 
B still, and, consequently, the valuable volatile pro- 
dacts are condensed and preserved. The oil, and 
iioUl and water, which distil over, dn not mix, and 
may be easily separated by further distiiUtion. The 
oU is an inferior oil of tur|ientinc. which ia useful 
In coarse painting. The acid is strong and cmpy- 
teumatic, very closely resembling the pyruligneouo 
tcid obtained from tht: di<itilUtion of wood. Uy 
this metliod of converting tar into pitch, ftOO 
gallons or 20 barrels of tar, will produce 10 barrels 
or 2,200 weight of pitch, 176 gallons of oil, and 
about Hi gallous uf acid. 



LIGHTHOUSES. 

Tns andent mode of exhibiting ligbU t» beacons lo 
the mariner consisted in boroing wood or cool in s 
cliaulTcr on the top of a tower : and till the yr^r ittQ7. 
the Kddyatone light was nothing better than tits 
feeble blaze of a few tallow candles, wlUiout aury 
apparatua for cooceatrating the lii;ht or giving il 
any particular dircotion. But uj ri*v' .*i i' ■'( (iro. 
ceeding from a luminous fiKUs are • iicd 

over the surface of tJie sphere wi»< 
for its centre, it is evident that without 
of giving the tight a horisQutsl direction, tiic 
part of it must be wholly loat ; for only 
which are directed in the plane of the ho 
at leaAt which src depressed only a few 
below it, can be seen by a ship at a distanoe. 
the first object to be attained ia to prevent 
of light by throwing the whole of it forward ia 
plana of the horizon, in order that its intensity i 
be increased in the greatest pusaible degree. 
there are two prinrtplea on which this may 
aocompUsbed, reOexion and refraction. T 
is accordingly carried into effect by a ^ 
dioptric spporatuti. Sometimea boUi priu>.>|'H« 
combined in the same spparatns. 

Catoptric ^yttem. — The usual mode of . 
the catoptric principle U by barnJng an 
lamp in the focus of a parabolic mirror 
mode of illumination appears to have been 
carried into effect at the Carduon tighlhousft. 
tlie direction of liorda, about the year 1780 
few years later reflccrting mirrum were placad 
some of the English lighthouses, nnder the 
of the Trinity House; and in 1786 the 
was adopted in the only two beacons then 
on the coast of Scotland ; viz. the Isle of 
tlie Firth of Forth, and the Cumbrae 14^ in 
Clyde. Soon aftcrwordc it was adopted 
in this country. Borda't reflector was ; 
sheet of copper piatod with silver ; thu^r 
in Scotland were formed of small far^^ts of 
glass, placed in hollow parabolic moulds 
The mirrors in general use in the British 
at the present time ore of copper lined with 
the focal length is about 3 or 4 feet, and the 
at the outer edge about 21 inches. 

If the curvature of a reflector coul." 
truly parabolic, and if the iij;ht isi< 
mathematical point, the rays would i 
from the mirror exactly parallel to thr 
generating curve, and the bt:am of pr. 
would be a cylinder having a dtameter f < 
of the mirror. Such a form of the I 
render the light nearly nseieas, on arvount 
small jmrtion of the horizon which would \ 
nateil ; and it is accordingly necessary to 
raya a certain decree of divergence ; chia 
caily effected by tlie sixe of the flame. TktB 
uf the lamp ia usually on inch in diameter 
the origin of the luminous rays being thi 
amall dttftance from the focus, instead 
reflected parallel, they arc projected in a cane 
a divergence of about \i'\ The curv.: 
mirror may alM bo so adjuated as to \ 
divergence. 

In order to produce a light of sofficientni 
several parabolic mirrors, aomebmrs as maSf i* 
eight, are placed on a frame, with their aao ifi 
parallel (o each other, so that the li^ht rcAt/UA 
by all uf Lhcm is blended togt-ther in lb« aaiM 
bauD. To form a revolving li^ht, the {nmt i* 



Mafi 



MAGAZINE OF SCIENCE. 



359 



1 a horizonlal uiU, which i> turned hy 
pcic marhinery ; and in thi§ manner the 
Iftrteri of the horizon nre BDccessively 
! But at a rapid motion would be tn- 
I the frame has aauallj three or four 
ph of which the nune number of inirron 
tti placed; so that the illuminatioD ii 
iPee or ftmr timea in one revolution. To 
tooary light, a number of reflectors nrc 
lid a dr(!ular frame, having their axes on 
I ihe circle. This ;arran(;ement has one 
lect ; numcly, that the illumioalioii wilt 
itly intense at all aximuths, but strongest 
iKoa of the several axes, and feeblest in 
p of liaes bisecting the several nrii;le« 
iMt p^of contiguous axes. The defect 
feh cannot be entirely remedied in a 
uht on the catoptric prinripte. 
r Sy9iem, — The introduction of lenses 

Eof giving the light a horizontal 
recent dale. A project for tltis 
Mi mentioned by Smeaton in his 
the Eddystone liijhthonse, and about the 
t last oentary the method was tried at 
lioufea in the south of England ; but 
imperfect figure of the lenses, and the 
tof the light caused by the great thickness 
i, it did not Bticcced. But the art uf 
jlherical lenses baring been since brought 
perfection, and a means of greatly di- 
|he absorption, and also of coiistruetiug 
fnucfa greater uxe, having been found iu 
polyzonal lenm, (that is to my, lenses 
'aeverml piecea separatety prepared and 
rtinited,) the system bos been revived of 
%nd in many instances carried success- 
iMecution. The merit of first applying 
to lighthonsci belongs to the late Auguste 
f Ihe Academy of Sciences of Paris. 
rleofes, constructed under the direction 
t for tile principal lighthoases in France, 
iDOvex, having a focal distance of about 
Id they are formed of crown glass, aa 
I liable to ftntp than flint glasn. The 
hrergcnco of the cone of light projected 
Is generally less than in the cose of a 
lil refractor, being only about h" 9', As 
lU cone is formed of only that portion 
bt which foils on ttie surface of the lens, 
I sopposed that an apparatus of this kind 
Jhf tatferior in its cflect to a paraboHt: 
■t when it is considered that, owing to 
Ibetiona of the form and polish of the 
narfaoe, more than one-half of the inci- 
I is lost in every cxse, nnd also that a 
I more Intrnae Hamc may be used fur 
Ig the lens than can bo applied to a para- 
bctor, it will easily appear tliat the 
i may be on the side of the lens. In hict, 
Ihe largat size used in the French light- 
bjecti a cone of ctjunl intensity to that of 
|bn of the best kind, 
batraction of a revolving dioptric appa- 
ihe first order is usually as follows : — 
Iking frame which carries the principal 
Kvight sides; and there are consequently 
I Icnsea, so arranged that their axe» are 
flame horizontal plane, and meet in the 
IImmu, where tlie lamp is pliiced. This 
Ith its Icfurg, consequently forms an 

SFor the purpose of preventing 
«ya which Call above and below the 



principal lenses, varioni methods are employed. 
One is to place above the Brst frame a second 
frame, whose sides form the frustom of an octa- 
gonal pyramid of 50^ of incliiiAtion, in each of the 
sides of which U placeji a lens having its focus in 
the flame of the lamp. The rays falling on tbene 
inclined lenses are refracted into directions parsllel 
to tlie axia of the lens, nnd are then reflected into 
the horizontal direction by plane mirrors placed 
above the second frame. Another method is to 
place carved reflectors above the frame containing 
the principal lenses. But a third and still more 
elegant method, proposed by FrcancI, is to subftti> 
tuCe for the upper lenses and mirrors a series of 
triangular prisma, having their axes arranged in 
horizontal planes, and so adjusted that the light 
falling on the face next the flame is thrown upon 
the bock of the prism, where it satTers n total re- 
flexion ; nnd n second refraction at the third side of 
the prism gives it the horizontal direction. 

For fixed lights on the dioptric system, it is ne- 
cessary to fncresife the number of the lenses, which 
in fact ought to be infinite, or to form a true 
cylinder, in order to produce an equal difTosion 
over every point of the horizon. In some of the 
French lighthouses the refmrting apparatus consists 
of a polygonal belt of thirty-two lenses; but on 
establishing a dioptric apparatus at the Isle of May 
lighthouse, in lK3fl, Mr. Alan Stevenson proposed 
to form a true cyllndric belt ; and the task, though 
attended with much difficulty, was suceessfully 
executed at a glass-house in Newcastle. 

The dioptric system is peculiarly adapted for 
fixed lights; and its advantages are these : — 1. A 
light of equal intensity la distributed round every 
point of the horizon. 3. The consumption of oil 
is less for the same intensity of light, and r^nsc- 
qaently the expense of maintaining the light is less. 
3. The trouble attending it is less, as there is only 
one lamp to trim, and the lenses are easily kept in 
order ; whereas the reflecting surfaces require maeh 
care and attention. On the other hand, there is 
more risk from accident, for the accidental extinction 
of the lamp leaves the whole horizon in darkness; 
whereas in a system of reflectors the light would be 
extinguished over only a small portion of it. 

Fresoel published his first memoir on the subject 
in IK22 ; since that time the dtoptrie system has 
been generally adopted for all the principal light- 
Imuses of France nnd Holland. In this country it 
hni BB yet been applied only at Inchkeith and the 
Iftle ofMay in the Firth of Forth, and at the Star 
Point in Devonshire. 

Lantpji. — For the lights on the catoptric system, 
the itlumination is usually produced by an ArganJ 
fountain lamp, having a burner of an inch in dia- 
meter, and tipped with silver, in order that it may 
the better witlistand tlte efl'ect of the heat evolved. 
In the dioptric system a larger flame is requisite; 
and Preanel invented a tamp, the peculiarity of 
which consists in its having a series of concentric 
burners. For lights of the first class the number 
is foor ; and they are protected from the efTects of 
the exceaaivR heat hy a superahnndant supply of 
oil. which is thrown up from the cistern below by 
a clock-work movement, and is kept constantly 
overflowing the wicks. A tall chimney is necessary 
to supply a BufHeiency of air. In this country the 
lamp is fed with spermaceti oil ; in France the oil 
of colza (cxpresfled from the seed of the wild 
cabba;;e,) is UAcd ; and in some parts of tlie 
Mediterranean olive oil, bat tho Ugbt obtained from 



ZQO 



MAGAZINE OF SCIENCE. 



thU U comparatively feeble. In » few instance* 
coal gis has been used for dioptric lights. All 
attempts to apply the JDnimmond light, and Toltaic 
li|;ht«, have ^ilrd, by rrmoti of the great practical 
diflicultiea with which thoai; modes of illumiaation 
are attended. 

Method of dixtingHuhiny S^a lAghtM. — An object 
of freat ic]|)ortance in the establishment of light* 
houses is to vary ibe sp[>earAnces of the different 
lights, so thst each may have some distiiictiTe 
cluracter by which It may be readily recoguized, 
and the mariner be made aware of the part of the 
coast he is approaching. Among tlio melliods 
adopted for this purjKne are the following : — 1. The 
interposition of colored shades before the lenses or 
refractors, so as to gire a particular color to the 
light : red is the only color which can be used, as 
shades of any other color are found to absorb too 
much light. 2. The time of revolution, or the 
lengtli of the interval between the successive ap- 
pearances of the light : this is the ooly mode of 
distinguishing lights adopted on tlie French coasts. 
3. A fiashing light ; that is, a light of which the 
alternate flashes and ecUpics succeed each other so 
rapidly as to give tlie appearance of a succession of 
brilliaDt scintillations. 4. An intermittent light, 
which consists of a fixed light which is suddenly 
eclipsed, and after a stated interval as suddenly re- 
Tested : the Appearance of this light is entirely 
difTcrent from that of any revolving light. 5. The 
exhibition of a double light, which admits of other 
distinctions ; for ,the one light may be placed 
vertically above the other, or in the same horbontal 
plane ; or one may be white and the other red. 
Sometimes Uiree lights are necessary to indicate the 
entmnces to harbours, &c. 

The overage annual expense of maintaining a 
land light in Great Britain is about dOO^., and that 
of 1 floatiog light about 1200^ 



DROPPING BOTTLE. 

{_Tu tht Ediit>r.) 
Sm.— Having observed, during the progress of your 
valuable *' Magazine of Science," &c., that your 
object bos been to explain and simplify to thL' un- 
derstanding of all, those subjects which arc usually 
considered, partly from the expense attending their 
study, and partly from the great difficulties in 
monipnlation, beyond the reach of the mojority, I 
have intruded upon your notice by sending you an 
account of a modifirntion of the drofiping bottle 
which is in ordinary use ; and which I think every 
person, having manipulated in chemistry to a very 
alight extent, most have found very inconvenient. 
1 think it is more useful just now, at the time when 
most chemiKta in snslyses use srcallcr qunntitics 
than they formerly employed, as in the tube che- 
mistry, where I have found it very useful. Of 
eourae you know the ordinary dropping bottle is 
mode of a common bottle, fitted with a cork, 
through which an operturc is made to fit in a tube 
tapering at one extremity to a fine point, and bent 
at a certain angle from the thicker part of the tube ; 
mother hole is tbcn cut in tbe side of the cork to 
allow air to enter the bottle to supply the place of 
the water which has escaped from the liotUe ; now, 
to ensure good action in this it is necessary that the 
aperture in the cork for the entrance of air, should 
always be quite free, but as soon as the bottle Is 



inverted, if the hole in the cork he nt sit Itr^ 
Ibe tube the least stopped up by a bubble » 
Burrouuded by water, the water rushes oot al 
side hole in the cork, and of conrse nuu ovei 
table, or down the side of your filter, or any* 
but where yon wont it; now my roodifir^UOQ i 
does away with this inconvenience, it is ihus:- 
Gut a bottle with rather a wide mouth, and ia 
of having one lube, provide two, on** K.-'f-,.. w. 
longer than the other ; then make t ' 
cork, (which should At air-tight into ('■ 
the holes be equally distant from the edge ol 
cork, and from one another; one tube should 
a larger bore than the other, (the longest il| 
have the smallest bore,) thete two tubes «r« 
fitted into the apertures in the cork, the lot 
tub« being fixed »o, that when tbe cork is pUce 
the bottle it may be within the bottle, 
shortest and thickest must be outsiite 
Perhaps a sketch will simplify it. 




A is the shorter 
longer and thinner. 
moving the cork in 



and thicker tube ; B ts 
It may either be filled by 
the ordinary way. or the 
way is to immerse the bottle in water, and exh 
the air by the month at the orifice of tlie short t 
while the water rushes in at the other ; when i 
in this manner tbe cork may he varnished to 
bottle with tbe sealing-wax vamlsb ; when the b< 
u inclined in use, the water first falU in drups. 
then in a fine stream, which may be modifiei 
pleasure, and thus not a drop is rpillcd. 
quantity of water in the bottle ought to be 
more than when it is inverted, and may rise or tl 
a little below the orifice of the longest tube. 

I must now apolt^ize for havini; intruded M I 
upon your valuable time, remaining -.^^.-r...! i 
any person trying the itbove will finil 
the trouble, although comparatively & \ 
still it is a very great convenience. A oulio* 
this in your journal would, I am aure, be scrr 
able to t great number of your readAn. j.« 



-j^^^^KJVi^wrf^^ 



SIR R. PHILLIPS'S RULES FOR 
PRESERVING HEALTH. 
1. Risk early, end never sit up late. 2. V^'ssh 
whole body every morning with cold water, by ue 
of s large sponge, and rub it dry with a rougn lol 
or scrub the whole body for ten or fifloeo minu 
with desh brushes. 3. Dnnk water gencrtUy, I 
avoid excess of spirits, wine, sod fermented liqw 
1. Keep the body open by the free use of tlui ) 
ringe, Olid remove superior obfrtructioos by ipeHi 
pills. .'). .Sleep in a room which has free moctm 
the open air. C. Keep the head coot fay wadil 
it when necessary with cold water, and abate fcvfff< 
and inflammatory symptoms when they arii* 
persevering stillness. 7. Conrct symptoms 
plethora and indigestion by eating and dnfiki! 
less per diem for a few days. B. Never eat a bM 
supper, especially of animal food ; and drink wU 
spirits, and beer, if tfaMc ore oeceuary, only rf 
dinner. 



Umvok.— Ptlaisd b 



1 by D. Francu. 6, Whiu Hone tsii*. M)Jt Knd.— I'ulilHlicd hy W, BsiriAiN. I 

Sdinburgb. ,1. Mntxiis.— OUigow. U. Brks ami i IfAOMM.— Uvtrpool, C. Pax 



Paiur. 



maA 




THE 



MAGAZINE OF SCIENCE 



P 



^nH ^cf)ool of ^vt$. 



150.] 



SATUHDAY. PEBRIURT It. 1841- 



[Urf. 





IX 2 



SUTCLIFFE'S PATENT ROTATOUY PUMP. 



3CS 



MAGAZINE OF SCIENCE. 



SUTCLIFFE'S PATENT ROTATORY PUMP. 

Thb following is n dtwription of SuMiffe*t 
puoip, with Uie rcfult of an ftxpcriment on the dii- 
cbaffpng power of one now at \Ti>rk ut Ihv Limerick 
Docki), where il is foimd fur inprrior to the chain 
and (tucking pumps bcfnre in niM!. Prom the facility 
with whirh it ran be i»]>ptir4l in nil thooe cnnes where 
pumps lire refjuirt^, and not hring subject to get out 
of refmir in clioaked, it proniite* to \yc foon very 
gmrnrfly afM>d, not only in hydnialic works, hot 
lino fn the iiftvy. and those ciues where the common 
pump was brfore used for household pur^Kitra. The 
patentee has hern filmniit rnn«tantly eonnertrd with 
the CsiL'cution of titm«ive worki, as superintendaiit 
under Sir Tlioninii Deane and Company, luid hiA 
atleution was directed to the mbject by the fre- 
(iucncy of repnira rei)uin:ii for the pumpii usually 
employed in clearing out water from foundntion* and 
dam», their preat frirtion, and the unefpifll flow of 
water from them; and wr are informed that liift in- 
vention has received (he approval of Mr. Rhodes, the 
en^oeer. and Sir Tbomn» Deane and Compaoy, the 
contractors for the Limerick Docks. 

In this pump a vacnum is formed by the rerolu- 
tion of an eUiptical fmnic wttliin a cylinder, when 
thewater riifini;, it ii carried round in the lunar ■ipaee 
Yietween the ellipse and circle, shown on section, and 
dischar^'d. 

In the annexed figures, Fig. 1, is a side elevation, 
Fig. 2, an end elevation. Fig. 3, a Tertical section 
alonK the length, and Fig. 4, a vertical section ecrocs 
the width of the pnmp. and the same letters refer 
to tlic same parts in each tigurc ; X X, the axis by 
the rotation of which the elliptical frame E E E E, 
is carried round in the direction Indicated by tiie 
arrow T, in Fig. 3 ; C C C C, the cvlinder in which 
E E K E, moves both, having the common ax» X 
X ; F F, • jacket forming with the exterior of the 
cylinder a passage for the rising water from tlie pipe 
P; T, and T, Fig. 3, two extreme imaitions of a 
tongue which hinders the water brought round in 
the lunes from M, of escaping again at the same 
place, and which ke^s touching the corface of the 
ellipse m its revolution j B 6 B B, a box into which 
the water is received and discharged through the 
itischarging pipe D, and when D is clow^d, forces 
the wnter by the reaction of the air above through 
the foreing pipe P. When the pump is to be used, 
water is thrown in ^in above^ which renders the 
contact between the elliptiril ralve or frame, and 
the cylinder water tight; after a few revolutions lh« 
air is exhsosted, and the water rising i.'> cirricd into 
B B B B, and discharged by D or P as before de- 
aeribed. It is evident the discharge will depend 
conjointly un the velocity and aectional area of the 
watirr pasting from the jacket into the luoea, and 
'the area of the laues and the velocity witli which 
they are formed, or carried round. \\'hen the 
▼ehwity and sectional area at M ia sufficient to fill 
a lune in the time of hnlf a revolution, a mAsimuni 
effect ia produced, and the diMrbarge is found when 
the velocity nt M is autfii'tcnt to fill the Innes, by 
multiplying the velocity of the Inaea by twice their 
area uf one. The foregoing figures tfe drawn from 
a pump of this con«tnicIian now at irork, and are 
Utd down on a scale uf tr-4ths of an inch to the 
foot, but the handles and fly an not shown. Pour 
men discharge 128 gallons through a mean lift of 
8 feer. 6 inches in 30 seconds, two men working at 
eacli handle, and the tly hcing about 4 feet 6 inches 
ia diameter. It shoold not be forgot that Che 



&cilily this constraction of pomp affonla for d» 
applicatian of a fly whvcl, iflbrds one tlitra^ not 
tbe first of ita reconimendaliaus. The water banes 
in one regular and I'ontinut-d rtream from the 4i*> 
charging pipe; chips and clay ttltnohed to ihrin wlini 
pa*aed into the pump, getting throuch without ia- 
jnring tbe motion or apparently taking from tkt 
discharge. 

SULPHUR. 

This is a very rrmarkable elementary form of mat. 
ter, and its chemical examination will afl'urd curatta 
and u«rful information. 

SnlpAurt or britnr/iittr, oa it la vulgarly caDed, b 
a mufct abuodinl and welUkoown •uhstaner, occur- 
ring in commerce in three atates, via., na/rre ml- 
phuTt roltirulphvT, mxdftortetr* v/mJphmr. Katirt 
mttphnr, so called from its occurring in a ffco «r 
uncorobined state, is found in Isrc" = in 

many ptrts of the world, and xf sin. -fitl 

in .Sicily, from whence the English i iioal 

e.<icluftively supplied ; it comes over ia large Mature 
or oblong blocks, into which forms it liaa bcm catL 
after undctrgoing a rough puriftcation by fusicmt 
and the quantity thus annually imported ia betwet* 
IG.OOO and 17.000 tons. 

It is the purest commercial rarieiy of sulphar, 
and is therefore largely consumed in the manufactuff 
of gunpowder, of sulphuric acid, and in some 
operations of bleaching. Besides being found in 
the native state, sulphur occurs in combiuatioD vitik 
many metals, forming a class of compound*., oUlftI 
mlpkureh: those of iron and of copper are «cO 
known to almost every one, under the coniaot 
names of iron and copper pyritca. 

Copper pyrites, or sulpburet of copper, is a moat 
important ore of copper; and in the mining 
tricts of Cornwall, during the oper&dona of' 
ducing the metal from ita ore, vast qnajitii 
sulphur are collected tn an import state ; it 
lied by being melted in pola, when part 
impurities rise to the surface, and are akimmed 
a small part settles to the hotlnni.ond the purrr 
tlons ore poured into cylindrical moulds uf boech* 
wood previoutly soaked in water to prcvOfll tht 
sulphur from sticking to them ; in these maaliU it 
concretes, and when lliey are opened, it eppesn in 
the state of roil rulphnr, stick ttipJkur, of raO 
brirrutone^ which it too well known lo requin aaf 
furtlier devcription. 

The chief, and indeed the almost exdoMfe 
mil sulphur, is for tipping common matehoi, 
consumption in this spparently triflinf 
manufacture ia aomething quite enormooa 
been calculated that not leaa than threa 
sulphur urc thus annually consumed In 
alone. Sulphur mat^hea are usually sold at titf rals 
of seven.pence per thousand, and tlte vilix of a 
year's consumption of them in EngUnrf amouittfd 
to somewhere about £26,000 aterling, prertousli so 
the introduction of ludfera. 

Ffntcer» uf ttitpknr, or Jt<m*er» ^ Irrmitlimef 
obtained by heating sulphur until U riaea In 
or sublimes into very large receiver*, wbera It 
or condenses very rapidly into the form of a 
yellow cryitaJline powder. It ia Ur^ly used 
pharmacy, but is unfit for tbe miiiiut' .' 

powder or fireworks, ia conoequciv 
a little acid, which is formed daring inc suuuuii 
and this acid is highly injurious to tbe 
t«nili employed in the art of pyratechxij< 



per. 



Ijondan 



bti^ 



ofheri 



MAGAZINE OF SCIENCE. 



363 



tfficnlty in nntlenitiuidinf why the terms 
and utitrk nt/phnr arc; appliod to the 
Brietf of tnlpbur ; for it muatbe sufficiently 
thkt Che form of the tubstaaco resembles 
roll t>r cyliDilrical fitick, but pfTbaps the 
the terniR flofpm of tiiiphnr, or powers 
iomft is not quite so obviou*. and tbercfuro 
~n eji|tUuatfon, which is as follows i — 

ttiom, or the oonrrrston of a solid sub- 
llo rapor by heat^ and the reconvcnion of 
into the solid state by cold, ii a process 
n ifiTrntrii by the earliest alchymiita, and 
Iferred the name of flout^rM upon all sucfa 
prodncta u were light and rtocculcut, 
idea (a fanctfal one) chat they bore some 
> the natural flowers of plaota, — hcitcc 
the Itf^bt and flocculeot form of sub* 

rnr,Jiowr$ of tulphtir; but this term at 
fery ooinmonly corrupted into _/?ai«r qf 
'perhaps on acuount of its state of division 
ting that of flour. The vnlgar term irinuiione 
Tvpcion of the Saxon word Amw/OMe, which 
burning-stone; a name applied to sulphur 

oe of its inflammable nature. 
I thus said a few words respecting the 
▼arietiea of sulphur, we will proceed to 
some of liA properties. It is a tolid sub* 
F ■ pale yellow color, considerably heavier 
its apeciftc ^rarity varyinj^ between 
Id 2*080 ; it la very brittle, admitting of 
to powder with the K^^aCeflt facility. A 
rcumstanne happens, when this is done in 
ly clean and dry Wedgwood's mortar, via., 
n of the fincly-powdered sulphur to ita 
that it will not fall out if the mortar be 
ipaide down, which can easily be tried by 
ing a bit of sulphur about the sice of a 
very finely. Tbia adhealon ia owing to 
ioa of eleotricity ; the aalphur by the 
mcs neyafwely electrical, and therefore 
J attracted to the interior surface of the 
icb i> potiiirely electrical, in obedience 
of the science of electririty, which 
that when bodies are in opp'urite electrical 
ct each other. The fuct of sulphur 
cal by friction may be proved id 
sinpty rubbing a stick of mil sal- 
briskly on a warm and dry flannel, and 
ing iC to gome littln fragments u( cut 
aabes. or gold le&f. any of which light 
will be Btrnni;ly attracted by it. 
fitnr is perfectly insoluble in water ; if a lump 
put into water, and left fur a day or two, it 
~ and that it has not diminished in weight 
: «• It ia thus insoluble in water, itiaalso 
Sulphur melts with great facility «pon 
Uon of a very moderate heat : pnt a little 
bottom of a small glass tube, about half 
diameter, and four inches long, closed 
ly at one end, and heat it gently by the 
f ■ ipirit-lamp ; on Che flrst application of 
t the Aulphor crackirs and splits (on account 
{ual expannon of itii partit'les by hril) ; 
iui tu melt, and soon becomes perfecUy 
of a bright yellowiah.brown color; but 
ue the heat, and you will And (contrary 
a might expect), that, instead of remain- 
it will soon become thick and pasty, so 
gth the tube may be inverted without any 
rhe sulphur running out ; it will, however, 
uidily as it cools. Tbi:i iii aviTV curious 

fvlpbur, iod remaioB u yetvnupUiaed. 



If, when in the pasty state, tlie heat la increased, 
thr sulphur will also regain ita fluidity, and begin to 
hot) rapidly, emitting a dark orange -colored vapor, 
which nablimes aud condenses m the upper aiid 
colder part of the tube. The temperature al which 
sulphur tirht enters into fiuioa is about 216° of 
Fahrenheit's scale ; this is only 4^ above the boiling 
point of water: it assumes the brown pasty bUta 
between 'MUi' and •100'^; it boils aud sublimes ol 
60U\ and il pure leaves no residue. 

In passing from tiie fluid to the solid state, sul- 
phur always manifevti a teniirncy to eis>iunic the 
crystalline form ; this will be seen upon ej^umining 
tbe central part of a stick of roll sulphur, but very 
beaotifUl crystals can be easily obtaioed by observ. 
log the following directions : — Take an earthen basin 
capable of holding about a pint, place it in a brge 
iron ladle containing snnd enough to aurronnd the 
basin op to its brim, set the ladle over a slow ftre, 
snd let it beat gradually ; then having broken two 
or three pounds of rnll sulpliur into bits as Urge as 
hoeel-nuts, drop them, a few at a time, into the 
basin, and aa they melt, add more, and so on by 
degrees, until the basin ia quite full of melted sul- 
phur ; then put on a thick worsted gbve, and lift 
the bssin out of the sand, and set it on tbe floor or 
upon a steady tsble, in order that it may cool gra- 
dually. Watch it as it cools, and there will be Ken 
small crystals beginning to form at its hides, which 
will presently shoot over tlui surface, and ss soon aa 
tlie whole sarfsce ia covered with tltem, Uy hold of 
the basin with « gloved hand, and quickly invert it, 
so Lhst the interior portion of lulphur, which is yet 
fluid, may run out into sii earthea pan placed to 
receive it ; hold the basin thus inverted for about 
half a minute, nnd then, upon examtninK its iuterior, 
it will be found cooipleicly lined with beautiful 
needle -ah aped crystals of sulphur. 

This is an example of cryslaUization being effected 
by the fusion and slow cooling of a solid substAOrr, 
and tbe larger the quantity of sulphur employed, 
and the clower it is allowed to cool, t)ie larger and 
the more perfect will the cryitslsbe; be careful 
not to employ loo much heat, or otfaerwiae tba sul- 
phur will become pasty and intractable : no more 
heat is requiMte than just enough to melt it. Sul- 
phur ia highly inflammable : it takes fire at the 
temperature of 3U0'' when heated in the open air, 
end barns with a peculiar pale blue light, emitting, 
at Uie same lime, a most suflbcating odour, com- 
monly called a "anlphury smell." The tip of a 
common mateh, when applied to red-hot tinder, 
in llie opcratiun of ** striking a light,'* furnishes at 
once a specimen of the flaoie of sulphur, ajid the 
odour of its combustion. 



DESTROYING MICE, \c. IN THBIft 
LURKING PLACES. 
M. Thknakd has submitted to the Academy of 
Sciences a plan for destroying noiioua animnls, 
when they have taken rcfujtr in their hiding placets. 
The irtstrumrnt for destruction is sulphuretted 
hydrogen, which be bad remarked to be peculiarly 
deleterious to aninial life. Animals, when allowed 
to brralhe the pure gas, fall down as if struck with 
a bullet. Even when considerably dilutcil with at- 
mospheric air, the riTects are deadly. A horse dies 
in less than a minute, in air containing ^ of this 
gas. A dog of mgderute size is speedily killed in 
air contunit\^ imm> while o greenflm-h eipires in a 
few MconJs in air poflse«fiiDg ^sW <>' sulphuretted 



8G4 



MAGAZINE OF SCIENCE. 



Ii^drognn. lnflacnc«cl by tbeie hcta, the Ffcncti 

cheuiisl proposed the employment of thi* i^ns to 
»i>vcrul tiidividualc for the purpote of extirputing 
noxioiift VLTinin, bat h» su$i;e«tion8 being treated 
wiib Indilference. be determined lo pat the method 
in pnctice by Ins own experiments. 

HU first trial was in no ipartment infested by 
tkIb, which showed themselves occasionally daring 
the day, aud at nit;Ul were actively engaged in 
plundering a chest of oats, tu which they had access 
through an npeftare of their own formstion. The 
holes by which they retreated amounting to IB in 
number, Thenard adapted to each of them in snc- 
oeaaiun, retorts caiMibhs of containing half a pint 
measure* by introducing the beak of the retort and 
filling ap the ioterral round its nock with plaster. 
Sttlpburtt of iron was depoMited in the retort, formed 
from a mixtare of iron tilings, snlphnr, and water, 
■nd dilute sulphuric ncid was iotnidoced by mesni 
of tube placed in the lobulure. The fulphoretted 
bydro^en was discnj^gc'd with great nipidity, and in 
a few minutes not a rai remained alive in the build- 
ing. His next experiment was in an old abbey, 
where he wns equally successful, and baring opened 
up part of the wall be found many dead rats. He 
recommends the application of thtt method to the 
destrucliun of molei, foxes, and all animals which 
c»niiut be extirpated by the usual means. Thenard 
then gives popular dlrpctions for the formation of 
the miterials required to produce the gas. 

Mix i parts of iron filing, and 3 parts flowers of 
sulphur in a mortar with n pesile. Pluce the mix- 
ture in a convenient vessel, and moisten it with 4 
parts of boiling water, stirring it with a piece of 
wood or glass. Add gradually afterwards 4 parts 
more of water, and introduce it into the retort. 
Pour Qpuu the mixture common oil of vitriol diluted 
with five times iu volume of water, and contioae 
to Add it gradually till the efierrescence ceases. 
8huold any of the gas escape into the apartment 
and occasion inconvenience it may be removed by 
Uropning a little sulphuric acid upon bleaching 
powder. The holes should be closed immediately, 
tu prevent the disagreeable effects of the patrefac- 
tiun of the carcases of the onimaU which have thus 
been destroyed. 



METALS USED FOR ANCIENT COINS. 
Thk metals ased fur ancient coins and medals are 
well known to be principilly throe ; gold, silver, 
and the vnnous mndificatioiis of copper. 

It is looked upon ns an undt^niuble oiiom among 
collectors, that tlie more ancient the gold employed 
ill coinage is, the greater is its purity. The standard 
of the utmost purity of gold is well known to be 
twenty-four carats. From thcHe twenty-four carats 
nimoftt every nation in modern Europe has deducted 
MiArly two, which are made up of uUoy ; so that 
tliir mnsL usual parity of coined gold amounts lo 
about twenty-two carats. 

Now the gold of the coinage of Philip of Mare- 
don, Alexander the Great, Demetrius, and other 
princes, and cities, within u few centuries of their 
res|M>ctiTo ages, is of superior purity, snd very little 
inferior to fine gold, indeed, the only reason which 
nppefirs, in thcw early times, to huva occasioned 
the use of alloy at all. seems to have been, Uiat, 
wilhfMit it entirely, the gold could not huve been 
workrd. Kor the fact is, that little more alloy is 
allowed than vas abHlultly ueccutry for the pur- 
poaea of fabriie^^on. 



The Roman gold coinage, down to Veapasiso, to 
very good, thouc;h not so pure, for there is otiTy « 
forty-eighth part of the fine (t<dJ allojr. Altar (bat 
prince, indee^l, the alloy i^ doubled, so llUC it rtaa 
to a twenty-foorth. 

The silver of the ancient Greek medals is nf 
correaponsive chastity, only admitting, oa the goU, 
a very minute proportion of alloy; in like monacf 
OS the general run of modem coinage bos likewisa 
observed the same proportion uf alloy in the gold 
and the silver coin, but the Roman ailver cmasge, 
even in its grestest antiquity and punly^ by fto 
means equals the Groek ; for as the sute paid all 
their debts in silver, its dabaaeneot «aa a icrmt 
advantage. However, it can never be eallcd baK 
money till the reign of Didius Jalianva, wbo. uiuan- 
dering great wealth i» his infamoas porobasr uf tba 
empire and subsetjuent donations lo the prsmorisoa. 
Co induce them to maintain ^t purchnsr. fi>un4 
himself forced to have recourse to a vast degrada- 
tion of the silver coinage. Aftar this period, • 
pound of such silver is only worth a third port ol 
the value of real silver. 

Proceeding to the brass employed in mintage by 
the ancients ; when pure, which is very uncotDiaaVa 
it consists of two kinds ; the red. or what ibt 
ancients culled Cyprian brass, what we call coppvri 
and the yellow. The lirst of these Is very uucotn* 
mon in the largest sixe of brass medals, or what sn 
called large brass ; but is common iu the other siscs. 
Taking ; the mixtures according to tbcir dignity, 
the first which occunt la eteeirum, being a oiixton 
of equal parts uf gold and silver. The coins of iho 
kings of the Cimmerian Bospborus, during ths 
im]ierial ages of Rome, are struck in this metal, svl 
are very scarce. 

The next in value was Corinthian brass ; had tlM 
ancients even struck a single modal in that meiat, 
which, {unfortunately for many a fond antiiiuary, 
they did not. That celebrated metal, during thi 
very little time it was ever known at all, was esr- 
taioly only employed iu the fabrication of raaea tai 
other ornamental toys. Indeed its nra of boot fa 
use was, at any rate, very short -, for Pliny the oiH 
tells ns. that for a long time it had been VOaAf 
unknown. With reason, therefore, we may Uo^ 
at those deluded authors, who pretend not only ts 
find this metal in imperial rains, but even lo fiud 
lliree kinds of it ; namely, 1st. That in which gnM 
predominates ; 2nd. That in which silver ia most 
eminent ; 3rd. That in which brass is the most 
plenteous metal. We suspect Enea Vico, one u( ttis 
earliest writers on medals, to have bees the author 
of this strange idea ; which Sarol, a writer of tb« 
beginning of the seventeenth century, had 
enough to confute. The mistake must have 
from the circumstance of the first propaj^tor nf it 
not being ubie to account for the various miitam 
and modifications of brass, obaervahle in anaaol 
coins of ihu large stie ; and whiohi especially in se 
common a metal, appear so odd to saodem eysa. 
But, not to mention the authority of Pliny, abeve 
ijuotod, which is perfect proof ; or Chat uf bitr 
autiquories, who all declare tluit tlicy have tievar 
seen one coin of Corintliian brsss, or hraaa rafaiglail 
with the slightest proportion of gold or silver; than 
is anotlier evidence of such simple struetare. aad 
yet snch vast weight, tbal n '' ' luork 

the absence uf the autiquarir tii»- 

sion. namely, that It i.n in tli' .., ..urth 

about a penny. Uiui this precioiLs mrtd ih discovend. 
As the great liz* and wagbt of theec oevs aiv w^U 



MAGAZINE OF SCIENCE. 



365 



luiDwn. uiil thcjr |isned in oomouui currency for 

)>rDnjr unlf, it were traljr sarprising coold 

iiti hare alTorded any gold or nlver in their 

:ijy, a j)redoDii nance of either metal ofer 

Ml 

ftict iB, that tboae coins, which aome aoti- 
denominate of Corinthian bnu, are only 
on ft mixture uf the red and yellow brass 
above. To pUce the succeediog sorts uf 
■ooording to their actiul value, were an 
iupcrtluous HI difficult. 
the Roman coin* are of what the Frenrh 
which is described as a mixture of copper, 
nd, nnd Uo, with a nftb part silver. The Abb^ 
Rodftelin, • noted collector of this century, had a 
wnapkla niie of this metal. The luile must of con- 
oe have been thewurk of the Kgyptiaua, who 
that metal, or of Roman forgers, throuj;h the 
ru^ns, in imitadon of the silver currency. 
,4ikewiBe that sort called by the lUiiacus 
■re common in the third aud fourth 
n emperon, and are only of copper 
fttfed nr washed with silver. Many coins of what 
ia called l.irge brass are of those mixtures now oatled 
pot-metal and bcll-melal. There are medals of 
Nero of a most debased and brittle brass. After the 
^yt of GallieiiUB coinage of brass with • very 
minute addiliun uf silver may, be in many inilauLies 
re^rdcd aa that aothoritird by the stare. As may 
thou of copper or Iron plated with silver, which 
always, however, cousole the collector, for their 
liifflinution of iutrinsic valoe, by their indahitable 
uity, 

* have been found in lead of undoubted 
ty : of the Greek those of Tif^ranes in par- 
In Rome they must have been pretty un- 
for Plautus mentions them in one or two 
of his plays ; and a few imperial ones have 
fimnd. TQit strange work the NolUia Imperii 
, written in the days of Arcadius and llo- 
Boriiui, and worthy of that benij^^htcd |>eriod, men- 
Uon*i coins uf leather, among uLbers, of which 
ona are there given ; and which are totally 
Any indent coins yet found or ever to be 
Ibvwi* It may not be improper to add a hint as to the 
oumtwr of ancient coins, with quite difTerent re- 
which we have. The Abbve Kothelin had 
cabinet no leas than I8UU coins of Probus, 
was but of seven yean. The aumber 
n gold imperial coina may amount to 3000 ; 
ver to tiUUO ; and the braas to 30.000. The 
of the difTereot ancient coina, known to m, 
50,000. 





SHOOTING STABS. 

OTT^n uid nature of tliese well-known meteors 
involved in great obscurity, and have, uf Ule 
j«ars, excited extraordinary interest by their f>e* 
flodtoal appuranoea in anut.ually great numbers. 

phenumena fff Shooting Utart. — The apparenC 
magnitadrs nf these meteors are widely different. 
Tbo greater part of tham reaemble stars of the 3d, 
4tii, &tli, and 6lh magnitudes ; but some oecur 
which aorpaaa stars of the 1st magnitude, and even 
ciooed Jupiter aud Venus in brilliiuicy. In some 
0# them the globular form can be easily recognized : 
Iheae sre, iu every respect, simitar laJire-balU; 
aa<l. in fact, it is inipusiible, frum their nppearaticrs, 
io inako any duLincUon between the larger shooUng 
aUnand Ibe smullrr individuuU of nx-teors to which 
of fire-balhi u usually aj>pfoprialcd. 



Shooting stars appear to be equally numeruos in 
every climate. The weather seema to have no in- 
fluence upon their number. They are obterved at 
all times of thi! year ; but, genersily speaking, they 
appear lo be more abundant in the end of summer 
and autumn than at the other seasons. 

Some of the shouting stars leave a luminous train 
behind them, which marks their path through the 
sky with a milk.white light. These trains for the 
most part disappear in a few seconds ; but some- 
times they continue longar, and even for several 
minutes. In the case of actual (ire-balls, Dr. 
Olbera observed trains which continued from six to 
seven minutes ; and Brandes, in one instance, esti- 
mated that fifteen minutes elapsed between the ex. 
tinolion of the fire-ball and the diaappearanoe of 
the lumiuous train. The trains in general aaivmo 
tlie form of a cylinder, the interior of which is void 
of luminous matter ; and not uofrequently, before 
tlieir dhtappearaare, they take a curved form. The 
most probahli* explauatioo is, that they are caused 
by a gaseou6 matter left behind by the meteor, and 
bent by currents of air. 

The older philosophers bad formed various theoriea 
to explain these remarkable phenomena. By some 
they were supposed to be the producu of an oily 
sulphurous TBpor existing in the atmosphere, which 
liciug disposed in thin layers, and becoming inflamed 
by some means, would exhibit the oppearance of a 
clear brilliant spark passing rapidly from one point 
to another. About the middle of the last century, 
when the effects and phenomena of electrioity began 
to be butter understood, Beccaria and VaauU, 
among others, regarded tbe shootiog stars as merely 
electrical sparks; an hypotliesis which was aoon 
shown to be untenable. At a later period, when 
the intiaumablennturc of the gases became- known, 
Lavoisier, V'olta, Herbert, Toaldo, Greo, and others, 
referred these meteors to hydrogen gaa, which, by 
reason of its inferior density, they stipposed must 
be accumulated in tbe higher regions of ttn atmoa- 
phere. Dalton, however, ahofred that such ac- 
cumulation cannot take place, inoamuch as all the 
gases which constitute the atmosphere must be 
equally diffused through its whole extent, accordiog 
to the law of Marlottc. Dcloc maintained that 
certain phosphoric exhalations generated in the 
earth, and becoming inflamed in the sky, formed 
the true esteuce of the ihooling stars. 

In thia state tbe subject remained when ChUdnl 
published his celebrated work, on the causes of the 
masses of iron and other similar substances foond 
in Siberia by Pallas, in which be clearly established, 
by comparing the oircumsUnces of a great multi- 
tude of observations, that Ibe fire-baUs are meteors 
having their origin beyond our attnoaphcre ; that, 
in fact, they are masses of nebulous matter moving 
in space with planetary velocities, which, when they 
come in the way of the earth in its revolution about 
the sun. and enter the atmosphere, are ioflamed by 
itj rmiatance and friction, and become luminous, 
sometimes scattering mosses of stone atid iron on 
the ground. Ualley. WalUs, FHngle, Maskclyne, 
and others, hod previously assigned a coemical 
origin to these meteors, bat without suspecting that 
masses of stone and iron fell from them. The close 
rcaembknce which the greater part of the shooting 
stars present to fire-balls, at ouce induced Chladni 
to consider these phenomena also as cusmicAl ; tliot 
is to say, as small masses of matter not htvving their 
origin in our Hlmoiphere, but entering it from witli- 
out, and wliich are cither enliiely consumed in it. 



SG6 



MAGAZINE OF SCIENCE. 



or become eitinguiihed when tbey have pBMcd 
beyond It. 

Tht-M CQDcliisioni, howcTer, reqaired to be eon- 
firmed hj s more accurate investigadon of the phe- 
Domrnii ; for at yet no euurt determuivtton h«d 
Xhxq made of the ttcto&l average heighta of the 
abooting itan above the earth, or of their orbita, 
vekMiCiea, or magoitodea. In the year 1798, this 
hnportant bat difficolt inquiry was undertaken by 
Profflsaors Brandea of Leipsig, and Beouobcrf of 
DiiiKldorf (both at that time atudenta in Gotdti- 
gen). Having flel(*cted a base line, about 9 miles 
in lengtU, they placed themselves at its utremities 
oo appointed nights, and obaerved all the shooting 
stars which appeared, tracing their courses through 
the boaveDB on a celestial map, and noting the 
initatita of their appearancea and extinctions by 
chrnnometers previousty compared. The difTerenoei 
of the psths traced on the maps afforded data for 
the <leterminstion of the parallaxes, and conse- 
qucntly the heigfau and the lengths of the orbita. 
On six eveninga, between iMrptcmber and Novem- 
ber, the whole number of shooting stars seen by 
both observers was 402 ; of these 22 were identified 
as having been observed by each in such u manner 
that the altitude of the meteor above the ground at 
the inatani of extinction could be computed. Tlie 
leaat of the altitudes waa alwut ti English milea. 
Of the whole there were 7 under ih miles; be- 
tween 4S and 90 ; 6 above 90 ; and the highest was 
above 140 miles. There were only 2 ohfterred ao 
completely as to aiford data for determining the 
velocity. The first gave 25 milea, and the tecond 
from 17 to 'i\ milea in a second. The most re- 
markable result was, that one of them certainly was 
observed not to Ja/l, but to move in a direction sway 
from the earth. 

By these observations a precise idea wti first ob- 
taiucd of the altitudes, distancca, and velocities of 
these singular meteorv. A similar but more ex- 
tended plan of observation was organized by 
Brandes in IH'i^i, and carried into effect at Drealau 
and the nrighbouring towns by a considerable num- 
ber of ]H:rsons, observing at the same time on con- 
certed nights. Between Apnl and October about 
1800 shooting stars were noted at the different 
places ; out uf which number ti2 were found which 
hiid been obaerved mmultaneously at more than one 
station, in such a manner that their resjwctive alti- 
tudes could be determined, and 3G otbrm of which 
the observations fomisbed data for estimating the 
entire orbits. Of these 98, the heights (at the time 
of R:itinrtion) of 4 were computed to be under 1& 
English miles; of 15 between 15 and 30 miles; 
of 32 between 30 and 45; of 33 between 45 and 
70; of 13 between 70 and 90; and of 11 shove 
90 miles. Of these last 2 had an altitude of about 
HO miles, I of 2'iO miles, 1 of 2H0, and there was 
one of which the height was estimated to noeed 
460 miles. 

Of the 3C compatfld orbits, in 26 instances the 
motion was downwards, in one oaae horizontal, and 
in the remaining 9 more or less upwarda. The 
velocities were between 18 and 36 miles in a second. 
The trajectories were frequently not straight lines, 
but incurvated sometimes in the horizutitsi and 
aomcbmea in the vertical direction, and Botaetiroes 
tbey were of a ser[tentine form. The predominat- 
ing direction of the motion of the meteors from 
uortb-east to south-west, contrary to that of the 
earth in its orbit, was very remarkable, and is im- 
|M)fUnt in nfercaoc lo their phyaiool theory. 



A aimilar set of obarrvations was made in Bel- 
gium in 1824, under the direction of M. QueLekt, 
the results of which »t^ puhlishrd in the Ammitirr 
lie ItruxtlieM for 1837. M. QueUrlet was ehtoly 
solicitous to determine the velocity uf the melinva. 
He obuinrd six correcponding observations freQ 
which this element could be deduced, and tbe ranUts 
varied from 10 to 2 J English milea m aeooad. Tibs 
mean of the six results gave a velocttr of aM^ 
seventeen miles |>er secoud, a Utile leas tun tllMll, 
the enrth in its orbit. 

Aouliier act of corresponding obsemttona wsi 
made in SwitxerUnd on the lOih of Augnat, IRMj 
a circumstantial account of which is given by U. 
Wortmann in Quttelel'M OtrrtupOHtUmct MmttJ' 
mahqu»t for July, 1839. M. Wartirmnn and Hvv 
other observers, provided with crlrstial charts, 
stationed tbemsdves at the observatory o( Gssiava* 
and the corresponding obs er vations were xatiSm 4 
Flanchettes, a village about CO intles to tb« oorA* 
east of that city. In the space of sersD and s hslf 
hours, the number of meteors observed by the aU 
observers at Geneva, was 381 ; and during Ave aad 
a half hours, the number obaerved at rUnchdtst 
by two observers, was 104. All tlie ciroom 
of the phenomena — the place of the apparitio! 
disappearance of each meteor, the time ir r~ 
visible, its brightnesA relatively to the h 
whether accompanied with a train, Sj:. — v. _._ 
fully noted, and the trajectories projected on a 1 
planisphere. The extent of the trMJectoriea deachM; 
by the meteors was very differeot, varying 
to 70^ of angular space. The velocitic 
also to differ considerably ; but tlie overage 
was supposed by M. Wartmano to be 26'* per 
It WM found, from the eompariaon of the 
taneous ohservationt, that the average height 
the ground was about 550 miles ; and h 
relative velocity was computed to be about 
miles in a second. But as the greater n 
moved in a direction opposite to thst of the 
in its orbit, the relative velocity tnuat be dimi 
by the earth's velocity (about 19 mites in a 
This still leaves upwards of 220 miles pi 
for the absolute velocitT of the trrti^r 
more than eleven times the orbtttt Uis 

esrtb, seven and a half times tha' 'liwS 

Mercury, and probably greater tkau that of Uh 
comets at tlieir peHbt^lia. 

Such are the principnl facts whicli have Trt hera 
established respecting the heights, vrlocttirs, sail 
orbits of the shooting stars ; and it is from \ham 
chiefly that we are enabled tu form anir jkrotMihle 
coujeclures respecting their origin. And amre it ts 
now established that no difference is (rfwervsbis bt- 
twcen the larger shooting stara and amall fire-balls, 
both having similar altitudes and velootttasr sad 
presenting absolutely the same appearaocet, «f 
may assume tht<m to be of the au'. ■ sjsd 

that whatever has been proved resp \'*Xh 

will apply equally to the larger aU<r....i.^ oi»is.— 
Whether the meteoric appearaiMwa to which Ifea 
Utter term is applied msy not inelode ob)eels if 
totally different natures, is s queatioii admitting af 
donbt. It is possible that among the shooting atars 
there may be objecU which are merely electric 
sparks, or which hsve Hicir origin in a|>ontjinrOfisly 
inflammable gases, kuown or unknown, rsistillgbl 
the alntus)fhero ; but the greater part of Uwift mMt 
be considered as identical with hrB*b«lls. 
fTobe tWHf Mned J 



MAGAZINE OF SCIENCE. 



3C7 



ETABLE TOOTH BRUSHES. 

ine martb-mallntr roots, cut them into 
fiTe or six inches, and of the thickoess 
rattsD cane. Drv them in the shade, 
h ac to make them Bhrivel. 
txly pulverise two ouncm of good dragon's 
k it into a flat-bottomed glued pan, with 
m of highly -rectified spirit, and half an 
fmih coaBorve of roses. Set it over a 
rcoal lire, and slir it ontil the dragon's 
inoWcd ; then put in nboat thirty of the 
Uow ftUcks ; btir them nbout, and carefully 
i, that all parti may abftorh the dye alike. 
|his anlil the bottom of the pnn be i^uite 
ibake and stir it over the fire, uotU the 
[perfectly dry and hard, 
ids of each root or stir.k should, previous 
Hon in the pan, be bruised gently by a 
for half an inch downwards, so as to open 
land thereby form a brush. 
fe geuerally used by dipping one of the 
M powder or opiate, and then, by rubbing 
{net the ttxth. which they cleanse and 
mirably. 

Vtfttalfle Tooth linmha. — There are 
INp sorts of these tooth brushes, which 
In the amme manner as the genuine ones. 
• basis, rattan cane, nr even common 
ia used instead of the marsh-mallow 



SENSES O? FISHES. 

te other red blooded animaU) hare most 

ro eyes. We say raoet, becaote, while 

failed to detect them st ail in a few 

whioh the gistrobrancbus Is an instance. 

aoableps, or loach, exhibits the won- 

fBulyof four apparent eyes, looking through 

k. Altogether the visual organs of fishes 

fversitica uf situatiDii, form, and external 

, more numerous and striking thnn those 

Vther taimals. The general situation of the 

Ubea is that of one on each side of the 

■lut are termed flat fish, they are however 

OB the same side, with a slightly oblique 

tbe habits of thes« fish force them to 

one ado oa tbe ground, without this 

■tiOD, tbe sight of one eye would have 

I bnt with the eyes thus placed, the fish 

both of them upwonlfl, as well to protect 

to watch for its prey which swims over it. 

of bearing in fishes have been the 

discuMioQ, their ciisteoce in them 

led by nataraliiits, until aoatomy at 

all doabt on this point, although 

are still sceptical on the subject. It is 

that even the observant Liunseos was 

satisfy himself that any auditory organs 

§ discnvi^red in fishes, an oversight which 

. arose from the particular spedmeiu he 

V as in soBsc fishes no external orifice can 

|d. But even when such it the case, there 

an internal auditory apparatus, and the 

wnxc reaches a tremulous mast veiled under 

idy UmrtU, and from thence the tremors 

pd over the tttuititt organ within. It was 

sappuscd that the oscillations gave a tre- 

puUe to the water around, and that Llicir 

a were imparted to the surface qf the 



bodf : whote irritability wmi thereby excited. But 
had this been tlie case, all impreaaions received muit 
have been general ; they could have had no local 
direction, which waa evidently contrary to observed 
facts, and to tbe phenomena of bearing altogether. 
The Abbe NoUet ascertained, by conclnsive experi- 
ments, detailed in the Nutoire de T Aeademie Roj/aie 
d*M Sciences, 1743, p. 2G, that the human ear was 
susceptible to sound when immersed in water. The 
attention of Camper, Hunter, Vic d'Axyr, and 
Monro, was afterwards directed to the demonstra* 
tion of the aaditive apparatut in theae animals. 

The auditive organ, hovrever, ia unqaestionably 
much more simple in fishes than in animals of a 
superior grade ; and there is, as regards this organ, 
a regular gradation from the first of the«e to fishes. 
It varies in different orders of them ; bnt in all it 
do^ eiiat, and consista of three curved tubes, which 
unite with one another : this union forms in some 
only one canal, as in the cod, salmon, ling ; and in 
others a pretty large cavity, as in the ray kind. In 
the jack or pike there is sn oblong bag, or blind 
prooest, which it an addition to these canals, and 
communicates with them at their union. 

As Babes thus evidently possess the organ of 
bearing, the faculty itself can be no longer doubtful ( 
and indeed numerous fucts have been brought for* 
ward in confirmation of its existence. Mr. Hunter 
caused a gun to be fired out of sight of a fifh-pond: 
the report affected the fish uniformly, so that they 
all vanished to the bottom, and were many minatei 
before they again made their appearance. Gold Bad 
silver fish have been frightened to death by the re- 
port of a pistol ; and any tudden noise, if coniider- 
ablc, will often make them start violently. In 
Germany it is common to snramon the fishes by a 
bell to be fed. la China, a kind of drum, called a 
tamtam, ia also employed to drive fishes into a net ; 
nor any other confirmatory facta wanting. 

The organs of taste in fishes are very obscure, 
though there is little reason to doubt that they have 
some discriminating powers in the choice of their 
food beyond that of smell, which we know to be 
very acute. The tongue is, however, very imper- 
fectly developed ; it presents no papilla:, and ia 
supplied with none of the usual gustatory nerves. 
Fishes have also been known to swallow the plummet 
of the fiabermao instead of the bait ; and hence it 
is probable that thia sense is at least indistinct and 
weak. In this, however, at in every other part ol 
our present subject, great diversity prevails. Codt 
for example, will swallow almost any thing, such ia 
their Tondty and insensibility : but on the other 
hand, it must be confessed, that some fishca are 
sufficiently dainty, and must be tempted by baita 
dressed op with epicurean nicety ; end were we to 
follow up the instructiona of tbe ancients, wesboald 
add easeotiol oiln to make the morsel more piquant. 
It is however probable, after all, that thta gasCrono- 
inic preference is determined rather by the acutenesa 
of thf imcll than by the taste ; and in this view it 
may indeed be poatible, that the effluvia from aome 
vegctnble oils may so reicmble the odours emitted 
by some Insects, as to mislead the fishes. 

Tbe organs of smell in these animals are both 
external and internal, and present an cndleas variety 
in form and itnicture in the different speoic*. In 
some the nostrils are single, and in otliers divided : 
they are round in the codfish, oval in tbe conger eaU 
and oblong in others. They are placed in eomecaaaa 
midway between the snout and eyes ; in others they 
approximate the eyea \ and in others again they are 



368 



MAGAZINE OF SCIENCE. 



nearer to tbr anont By meanf of muscolttr Tibres 
they CJtit contract or dilate their orifices. The in- 
ternal oUactory organi conRut, u in the Mnmrnalia, 
of osaeoas cavities, mpporting a mucnuit me mbnuie 
called pituitary, which ia of erqoisite flennibility, 
and uprn to the emanBtioos given off from boilies. 
The olfactory nerves have their origin in ivclling« 
or tubercles, almost as lar^ aa the braJn itself. In 
the cartiliiginous tribes tbeie nerves are very soft ; 
in the npinoug they are lonff and slender : and in 
fact, fi}tlowiDg the analogies of the other organs of 
aense, their peculiarities of ttructure are endless. 
Finally, they are ramified throughout the pituitary 
merolvane. 

The sense of smell in fishes is supposed by some 
to bfl very acute; but although Dr. Fleming con- 
aiders tbe organs themselves as furnishing a useful 
piide to a systematic distribution of the species, yet 
be does not think the sense of smell so well defined 
as migbt be wished. This is a subject which greatly 
concerns the angler ; and we will onrsclvea observe 
on it, that the well known voraciousness of fishes, 
and the eagerness with which they will seize a metal 
button, or any glittering object, oil seem to point 
out tbe organ of sight as the principal instrument 
by which they dincover their food, and cons^-quently 
that the angler's aim should be dlnM-ted to that 
point. Tbe acutcness ur dulness tn the sense of 
smelling among fishes is ttierrfore to a certain de- 
gree undetermined. The fishers of early times 
indeed attributed to them a love of every savoury 
substance, und of many fetid matters ; while, as we 
have already remarked, essential oils were deemed 
irresistible lures to them. And these opinions are 
so prevalent in all treatises on tcthyology, and appa- 
rently so founded on fact, that we cannot but yield 
some crrdenee to tbe assertions respecting the acute- 
neM of these alleged olfactory pcrceptioiis, which 
indeed the presence and marked development of tbe 
organ might of themselves lead us to cipect. 

The organs of touch in fishes are not strongly 
marked. The skin is destitute of the papillary 
membrane ; and this circumstance has engendered 
in the minds of anatomists a belief, tliat the sense 
of touch is altogether wanting, or at best but very 
obscure. The well known fact, however, that both 
'jack and trout, particularly the latter, enjoy the 
titiilation of the hand, and even lean thereon for 
more close contact (in which propensity has ori> 
ginatrd the poacher's liabit of tuking the lai^est trout 
by tickling, as it is termed), is a sufficient proof 
that the sense does exist, and that in some fishes it 
is active. In irritability also they arr? not defective, 
as appears fhim the resistance they moke to violence, 
hni nevertheless we do not believe their feeliogs to 
DaacDte. 

Pishes have no organs of voice. This defect must 
be appareut, when we consider that they have neither 
larynx nor lungs properly so called. The snmll 
sound emitted by them occasionally is a kind of 
sigh, produced by c:xpcUiog the air ihrough the 
nearly closed gill-fiap. The dying snap of the 
herring is caust'd by a convulsix'e dosing of the 
some part ; and the sucking or chuck of the chub, 
la varm sunny days, when swimming near the sur- 
face, is, we are inclined to think, efTected by the lips. 
This aetion may probably be occasioned hy some 
application of the month to the large leaves of 
aquatic plants, for it la most observable when the 
flsbes are beneath or near them. 



SPECTACLES. 

HULKS rOR JUDGINO WHEN TH8 B1 

THa as61sta:(ck or. 

1. When we are obliged to remove 
to s considerable distance from the eja! 
see them distinctly. 

2. If we find it necessary to get mt 
formerly, as, for insCanoet to place tbe i 
the eye and the object. 

3. If, on looking at, and 
a Dear object, it fatigues the eye 
fused, or if it appears to,have a 
mist before it. 

i. When small printed letters are 
into each other, and hence, by lool 
on them, appear double or treble 

5. If the eyes are so fatigned by a 
that we are obliged to shut them from 
to OS to relieve them by looking at diffi 

When all these circumstances coi 
of them separately takes place, it will 
to seek ossistance from glasses, which 
eyes, and in some degree check their 
become worse : whereas, if they be not 
time, the weakness will be considerahl' 
and tbe eyes be impaired by tbe efToi 
compelled to exert. 



MEMORA>roA. 



Pein*a CompotiHoH /or Cortring 
Imrdest and purest limestone (white 
preferred) free from sand clay, or oti 
calcine it in a reverbcratory furnace, pi 
pass it through a sieve. One part, by i 
be mixed with two parts of clay well 
similsrly pulverized, conducting the whofl 
with great care. This forms the first po 
second is to be mode of one part of Oi 
pulverised gypsum, to which is added 
clay, baked and pulverised. These 
are to be combined, and intlmatt-ly incOi 
as to form a perfect mixture. M'benit 
mix it with about a fourth port of 
wafer, added gradually, stirring the n 
whole time, until it forms a thick pi 
state it is to be spread like mortar opon 
surface. It becomes iu time as hard as i 
no moisture to penetrate, and is not 
beat. When well prepared it will last 
of time. When in its plastic or soft •! 
be colored of any desired tint. 

Rett Japan.— ~VoT this purpose the 
japan ground must be made up with n 
ground up with oil of turpentine ; thU 
first grouud ; when perfectly dry, a : 
must be applied, composed of lake and 
varnish ; and tbe lost with a coat eoi 
mixture of copal and turpenttue varoiil 
with lake. 

Biue Japan. — The first coat most b4 
artificial carbonate of barytes, grooil 
varnish ; the seooad with Pntaaian Unfi 
copal varnish, and finnhed as before std 

Sihek Japan. — This is obtaJned I 
finely levigated ivory black, ground up 
oil varnish ; the second coat must a 
same pigment ground up in copal vacnji 



taK»oii,-.PrtaUMl by D. FaAitcM. 6. Whito Hotm t«iuM. Mil* Sod.— FubUshw) by W. BatriAiw. It, _ 
Ctrauminlcauoui, rwbkcb arv atuwcrcd Moathly.) to bt addreistdtothe Editor, at 27. Cvtlagt Ciwa, 



THE 



AGAZINE OF SCIENCE, 



^nH Stfiool of !^rtj$. 




370 



MAGAZIVE OF SCIENCE. 



TOWELL AND LEALANDS MICROSCOPB. 

Tnc dnily acUnowtedi^ecl adTnntflen aruing^ to erf ry 
branch of natuful «cicn(^u from tho lue of tliti mi- 
croscofie linvt; induced u» to {irr-vriit, aftrr aoine 
year*' rxp«rience, un instrnnitnt inotlifitrtl tu the 
}ire»i?nt improTemimbi, and more trithiii the reach 
(if M-i(*ntifii; cittf^rvrr^, tUmi that rtr. have of hilr 
coiifltrucced. In the following deHrriptiua Almost 
every portion of the instrument \» atludrd to, and 
ftguren of the dilTerent parla apjiendrd ; and it haji 
been our ohJMt to give every individual crrilit for 
bia improvements, where at leut we corisidrr them 
<it inch iniportunce ai to be pUeed on record. 

The points mowt drsfrvinK of ittvntion are the 
foUnwinif : — The dooble pillar, aa tirst made by 
Mr. Georj;o Jaokion, which jKHWiset the advuiitage 
of being ligbter. and dlatrihutca the vrrtftbt more 
equally upon the fuot. We huvc iilso introduced a 
circular motion to turn the ho<ly olP the HUp- to ex- 
iiinine the olijcct. and to ('li'in;;r ihi'^ oltjr-ri-i^liit.^ (o 
prevent it fruin folliiiij; upon t!io ohjr--t. I'he fitage 
is made lorcer and Mtroin^ lit4n in runner micra- 
■ropea of this *rie, nnd tt'x pinion and iirtt'nr are of 
the unie diameter m in lari^er iuMnitnenty, This 
deacriptiun of itage vtoj firvt coDi(rnrt«-d by Mr. 
Tarrell. There are, howcrer, two or three other 
improvements and modificotiooB, such aa the method 
for adju»tinK the object-^hisit tu coiiiprnsate for the 
khickne!«i of Iho glaas covtnnK the olijecl. 

Hg. 1. TAf Micrtitcnj/e in thv j}*mtvjHjhr gmrraf 
CMT. — Ai the ino»t cunvcniirnt; method nf using the 
inatrument is in thii position, it vrill be nrcesanry 
after tilting it oat of the case, to turn it by menna 
of the pillnri on ita moveable foot, in order that ihe 
{irinci|iiil weight vxny tie over one of the feet. Wiicn 
the person ufting it ia «randing, and tht: body of tlie 
inicro!rCv|>e perpendicular, it i« then firmest as taken 
from the cuse. A, the coarae adjuittiuent for tlte 
body, which rest* on two rallers, and is moved by 
I ruck and pinion, fi. the line adjustment, whicli 
is ■ screw with a cone, avaintt which there is a spring 
pressing against the cradle, whicli carries the rom- 
pound body. C, milled head, which moves the sta^ 
to the right and left. D, hends that move tiic stage 
at right angles to the otlu-r (C) — thero is one head 
on esch siile of the stage to this motion, in order 
that both hands mny be emplojrd at the same time, 
one on C, and the other on the opposite side, M-hcn 
• rotatory muTemeuC ia required to search for anl- 
nulcules. or other objects. When the two screws, 
C and I), are used tngriber, n diagonal moiiun* 
and when lepnrate, motions at right angles with each 
other ore obtained. E arm for holding the stops, 
F F F, (fig. 2,) which are used when viewing op»(|ue 
objfi:ts. — To pliice them for we, puali down the 
mirror G to the extremity of the stem ; pat the stop 
into the apring-hole, turn it into the centre of the 
fttage. and raise it as high as the slide on which the 
object is placed will udout of. G mirror for iUa- 
rnintittng objects,— When the concave side is used 
it should be raised nearly to the stem, in order that 
the mys nf light proceeding from it may reach the 
iibM'.-(-t iK'fore cTOSiting, for hy this mrnns the most 
iuien»e light is obtained. It is Invariably used for 
opaque objects, together with the lieberkuhn. At 
night it will be necessary to une the larger condensing 
lens, which should be placed at about, its focal dis- 
tance from the lamp, with Its convex side to the 
mirror, and adjusted till the rayn of light fill it. 
11, spring-piece for holding the hlidr.i on tlic stJige.— 
Tb£ most conveaieut mode of placing Lhem is, to 



posh op the sprir^'plree suffieimtly bifh to 
tlie sitae lo go on the ^ge, and titen cowpnaa il 
until it holds it. Any number nf slidea of the 
width rosy tbtru, after it hu been set. ■ 
without that Iruublr. Should the sliii 
wide, in onlcr to have the whole range ul ;. - 
it will be necessary to observe if Ihe rentrc of Ika 
slide cikrrfKponds with the Unc on the centra gf IW 
stage; if not. U must be altered until it dors 

Fig. 3. AchrofHOtic Coudrturr. — This i^ fldaptol 
under the stage. It will be obser*' -• tm* 

notches in the plate, capable of n<; t.w6 

springs on the condi»n«r ; put it in, nn-j ^ui m ti till 
the milled bead is in the best po*!iiJ<in for u»e ; bring 
your objert into foruf. and adjust the rniidnm-r lid 
you Kce diatinrtly the image t>i the lam|t. or the 
frame of the window, if by duylight; and then yi>lL 
Diay be assured the most intense light i* obuinul, 
which is not always desifablc. The light is li.jweii«d 
or diminished by turning back the ooadaBaing 
by means of the milled head. 

Fig. ♦. Micrometer /'jr meftniHnff oftjrrt!*.— Tba 
npper part of the Htag« is tuk(:n out k^i liie plattf, 
put into thr micrumetL-r, And the whole |tut aftla 
on to the stage. To measure an object, obacnc 
the micrometer stand* at nought ; then adjust 
edge of the object till it comes m contact with Uur 
web iu the eye-piece, by the mlllrd head Ci than 
adjust it across by the head of the uitcrutuetci Ui 
when tlie number of revolutions and points mmj 
be taken. 

Pig. fi. P flint holder for tiewing CAara» Sfe. 
in a thing jt/a/e.—It is adapted to (o in tJte plait 
of thf stage, and is put ia after taking the offti 

part cf the stage uj. 

Fig. 6. Uiaphram of French eotiMtrueiitm.'— 
Whiih ia used in front of the lamp, to cut off u- 
traiicoua light, and intercept the rays before ihey 
reach the mirror. It goes into the stem of theAfr^ 
roudenfting lensi which is eusily drawn out, 
diaphram sabstitated. It abould bo placed 
eight inches from the mirror, and if an 
aperture is olitaincd in the body, bat asmaU 
of the field of view will be illuminated, 
will depend upon which aperture is used, 
relative distances of the mirror from the object, 
the Uinphram from the mirror ; it is uacful, wlwB 
any very dflicate structarc is to be observed, ■« the 
darkness aronnd the object rendera the moritnp 
more distinct. 

w Ailjtuitiup Objt>ct^glane§. — Tbeae are made 
adjust, in order that they may be as perfi 
viewing objects covered with glass, as those 
not. As it ia of material consequence 
object-glass should adjust lo sutc the various 
ncflscs of glass that art! used, and as it u im 
to meuaare nceurnlely the thickness, the best m 
to adjatt the ohjeci-glass in this : — Place it st tka 
point for viewing objects uncovered, which will b* 
known by observing that the circular line uodtr tk» 
word uncoccted eurrespouds with the fued linr , uf. 
the more rejidy way is, to adjust it down aa far 
will allow, as we always maki" '^^ " ' ■ " ■■• ■' 
corrected point. Itnug the '■: 
adjustment of the body, then 
till the npper surface of the glass whidi ouven 
object is in fnrns ; this can very readily be i 
while Che person is obacrving. by taking bet 
finger and thumb the milling on the object 
and turning it to the left ; then bnng the 
again into focus by the body, and the adjuatURPi 
perfect. Fur the principle of this import«nt 



image I 



MAGAZINE OF SCIENCE. 



inrrrtiQj abjr£t>glaiMeA for looking tlirnugligUM, 
indebted to Mr, An*irrw Rv>h. 
7. Sftt^ Diw, hif which Dravinfft are 
. — To tut; it, pUw the body uf the nticroseope 
tfjUlj, tiike the cap oft' the cyc-jHece, push un 
ik to the line niarketl apun the long cvc-piCcc, 
it till the nrttt is horizontnl. 
rice of tho inftrunicnt above dcAcribcd 
>ni forty tn lixty guinnu, depending upon 
ibrr of powers and ■ ppjintun alLacbcd 
a %*ery oomplete mKTOdfO|iC, however, of 
kibd luujr he obUitiL-d for uhout fartj>lire 
\.—Ali^rroMcnpic Journal. 



SHOOTINQ STARS. 

T^fforjr uf the Shooting Start, — Some 

iphrrv, n% already elnlcd, have ascribed an 

ipherie origin both to the shouting stars and 

but the observation?) ot Urnndcs, and 

lAarticutarly those of WHrtmunn, «bicb profe 

of litem appear at allitudrs far beyond 

which Clin be assigned with nny probability 

lusplicre, have rendered ihi> Nup|MM)liou 

nalenable. Another hypothr^ts respecting 

In i*, that they are bodieit jimjected to our 

fireai volcanoes in the moon. Dr. Dlbers was 

It, perhaps, who showed the possibility of this 

Un computing the forces nt!>ceKS>ry to 

fme lh« mmio's nttriictioii, lie found tbjt a 

li«cted from thi: moon with i vrloclty of 

fcrt iu a second would not fall back un 

•urfxce, hut rr^Yde fiom it indefinltrly ; 

it ia order to rench the earth it is only ne- 

rj thtt the prtjjectile shoulJ have the velocity 

»0Q feet, which is quite conceivable, being only 

four or five times that of a cannon bill. The 

r t' ' . , nf infteoric stonrs 

■", Dettzenbur^. and 

. . - .. . ... iiLci of the shuoting 

ltd this origin extmnely improbuute 

Uuiin. In order to (inter our at- 

^irith a velocity of 20 milra in a second, 

tlioirn that if they come from the moon 

k«v« been projected from the lanar surface 

tty of about 120,i)00 feet in a second, 

be regarded as altogether impoMible, 

'■|i|iears that those shooting stars nnd fire- 

li*v« (he pUnctary velocity of from 20 

in ■ oecond, cannot witli any probability 

■f having tlielr origin in the noon. 

ly iudividiul bodies moving with u laisller 

ly have s lunar origin, is a question which 

V answered. " To me," says 

:s not appear at al! probable; 

^an, in its present circumstuices, 

»e1y peaceable neighbour, wtmh, from 

of water and atixioaphere, is do longer 

any strong explooiooa.** 

ithrfis fint suggt:stcd by Cbladnt ia Uut 

ra to have met with most favor, baring 

lt«d by Arago and other eminent nstruno- 

le ptc»cat day to explain the Nov«nil>er 

ioin«na. It consists in supposing thsl, inde- 

uf the great planets, there extat in the 

regions myriadi of small bodies wbtcb 

mt the sun, generally in t;roup« of zones ; 

ttxm nf thf*e aooes iotentect the eclipttc, 

>iueqoently enoovntcred by the earth in 

reirolution. Tlie principal dillii^ullii's 

this theory wt the following : — First, that 



bodiet moving in groups in the circaiustani<cs su))< 
posed niusL nermit.inly move in the same direction, 
and consequently, whfn ibey liecome viftihle from 
the earth, nould all appear to cmaoate from one 
point and move towards the opposite. Now, although 
the ni'scnrations seem to show tiiat the pn:domin*tiiig 
directiou it from nortb-eaic to south-west, yctihoot> 
ing stars are observed on the siune nights toeoiansttf 
from all points of the heavens, and to move in all 
p»s«>ible dirifcLiuna. Secondly, thtrir average velocity 
(e^prriiilly as determined fay Warlmatm) greatly 
exceeds that which any body circuiting about lb« 
lun can have at the distance of the earth. Tliirdly^ 
from their appearance, and the luminous train vihielt 
tliey generally leave bt^bind thcoi, and wliich ufiea 
remains visible for several seconds, somelimcs for 
whole niiiiutes. end iIm> from their being sitnated 
within the earth's ahadow, and nt hctKhis far ex- 
ceeding those at which the atmosphfTr can be 
supposed capable of sti]>purting combustion, It Is 
manif(.-»t thut ibeir lif;ht is not retlrctcd from tbo 
sun ; they uiusl thcrefurc be self- luminous, which 
is contrary tu every analogy of the soUr fiysieni. 
Fourthly, if massrv of oilIN matter approarhrd go 
near the earth at many of the obootiug sCirs in, 
some of tlicru would inevitably be attracted to it; 
but of tlie ihuu».and9 nf shooling starji which have 
been observed, there ia no anthcnticuled instanee of 
any one having nrtually rcncticd thi' nirth. Fifthly, 
instead of the (ucteors being attracted tn the earth, 
some of them arc ubiurvcd actually to rise upwards, 
unil to deiMtril>c orhiln whirh mrv convex towards Lha 
earth ; n eircuhisuiu-e of which, oa the present 
hypulhrsis, it acems diOIcaU lo give any rational 
eiplatiation. 

From tlie difficulties attending every hypothesis 
wUidi has hitherto been proposed, it muy be iuCcrretl 
how very little real kaowied^e has yet been obtnincd 
rea|iectiiig the nature of the shooting starf. It is 
crrtnin thnt l]i<-y a|ipi:4r ot great altititdi>s ahovi; tlie 
earth, and that they niovt' mlh prodigious velocity; 
but every thing else renpeoling thtrm is iuvuived in 
profound mystery. From the uhole of the facts, 
M. Wortmaon thinks tli:it the most rational con- 
clusion we cnn adopt is, that the metetjrs pruhably 
owe tlii'ir origin to the dispngngemont of electricity, 
or uf some analogous matter, which takes place ia 
the celestial regions on eycry occdainn in which Che 
condittui;s ooeessary for the productiua of tho 
phenomena are renewed. 

The presumptions in favor of tbe cosmical origin 
of the sbouUng stars are cbitily founded on their 
periodical recurrence at cM^rtain epochs of tbe ycor,. 
and the extraordinary ilispliys of the phenomena la 
various yrur* on tlie nights of the 12th or 1.3tb of 
November. W> shall here merely utile thr principal 
circumstances sceompanyinfl; those of 17D0. wbieb 
put tbe notion of a titnar ocigio eotarely out of the 
question. 

On the ronrnini^ of the 13th of November. 1799, 
before sunrise, Uutubnidt and buoplund, then on 
the coflsC of Meiiico, were wilucs&cs to » remarkable 
esbibition of sboosing stars nnd firi'-lm!l«. They 
filled the part of tlu! heavcnti exlfiidnig from dne 
east to about 30'' towi;al-« the north and soutli. Tlicy 
rose from the horizon between the etiKl and cost- 
north-east points, described ores uf unvtjuaL magni- 
tude, and fell towiirds the south ; some of tbcm rose 
to the blight of iO'', all obove 26* or 30°. Many 
of them appeared to explode, bni the Intger number 
itisiippL'firfd witliout emitting fipKfks: S'*me bad & 
uudciu opparonlly cqaal to Jupiter. Thi& 



MAGAZINE OF SCIENCE. 



remarkAble ip«ctacle wu seen at the uune time in 
Cumtaa, oa the borders of BraxiU in Kreoch Goiana, 
in tUe cUuinet of Bahami, on the cuutmeiil of North 
Atnericit, in Lubradorr and in Greenland ; and ertsi 
at CarUrahc, llalle, and other plaoea in Gennanj* 
manj ahuoting itars were aeen ou the aame day. At 
NoiQ and Hotfenlh&l in Labrador, and at Nenhernhut 
and Ltcbtenau in Greenland, the meteors aeem to 
have npproacbed the nearest to the earth. At Nain 
thL7 fell towards all pointi of the horizon ; and 
some of Uiem hud a diameter which the tpcctators 
estimated at half an ell. 



STEAM AND THE STEAM ENGINE. 

(Ueruwuil /rum i>age 350.^ 
It hat been already atated, that Dr. Fapin had, 
preriotu to the practical development of Savory'a 
projects, employed hiii faculties upon the then 
known properties of steam ; yet, etideutly. Savory 
was tho first to conilmct a working and oaeful 
Rteam en^e; therefore, although the French claim 
for tlieir countrymen the merit of this noble ma- 
chine, yet we must admifj that our countryman has 
deservedly the preference, aud this ia admitted by 
all nations except the French. The expanftive force 
of steam, however, which Pspin bad previously ex- 
plained, although not the great power employed, 
seems for many years to hAve led to no result ; In 
fact, Papin liad abaudoned the experiments he bad 
at fir»t instituted as leading to no result, until tho 
celebrated Leibnitz, having seen one of Savory's 
engines in England, sent a description and draught 
of it to Fapin for htH opinion upon its merits ; then 
and not till then did Papin set hi& inveutivu faculties 
to bear sncccsHfully upon the subject. After a time, 
namely, in 1707, — he pubUahed a pamphlet, called, 
a •' New method of raising Water by the force of 
Fire." Id this pamphlet he described the foUowing 
engine : — 




A boiler A, made of copper, cimimunieate^ by a 
pipe B| with a cylinder 1. which forms the body oT 




the pump. This cylinder bos no bottom, Wt fcf 
connected to the curved pipe X, which eaten btto 
and oacends nearly to the top of the ciatcra 
R R, which tft Btr-tight, and is furnished with a pipa 
and cock P W. On the curved port ot the pips X 
is another pipe termmatinff with the funnel K, and 
having a stop-cock M. The feeding pipe B. has 
also a stop-cock Ct and jnst above is another )itp* 
V>. At Q is a conical valve, and at G o 9oJtty nthr. 
Also a eecond safety valve is at E on the boiler. 
When a sufficient quantity of steam is generated ia 
the boiler A, the cock C is opened, to allow ic lo 
flow into the pomp cylinder I. which we may sap- 
pose to be nearly filled with water, the steam pms<« 
by its elasticity upon the floater H ; and drpreaaes 
tt into the cylinder 1, forcing the water which tt 
beneatli it, through the curved pipe S, np the pipe 
X, till it falls into R R. The cock P is then opeiuil« 
and the water comprcsaed by the condenactl sir la 
the nppcr part of the cylioder, issnca with grest 
velocity upon the float boords of the wheel to wliidi 
it imparts motion. The reverse action obtained b; 
tho alteration of the cocks will be easily on 
A curious contrivance wilt be found in the 
of this engine. Papin was destroos at the 
of preventing the condensation of the iti 
into the cylinder, and also to promote its elosti 
with this view the floater had on its upper 
case or cylinder of iron, in which a red hot 
was placed, so that tlie steam instead of com 
contact vritb cold water, strock against tha ' 
iron, and thos acted with increased instead 
minished force in the water cylinder. The 
irons were renewed from time to time throogh 
valved orifice C. The trouble attending such i 
oontrivanue rendered it inrffipacions, still its inge- 
nuity will be readily conceded, ai well as the msiil 
of the safety valve in the boiler, the want of which 
was severely felt in Savory's engines. AnoLhsr 
thing ii worthy of remark, that is, the near appruach 
of the floater of Papin's cylinder to the piotiia 
afterwards employed, and also the circumstance tbtt 
when the steam is cut ofl', and the communicotidB 
with M, which is supposed to be connected with 
the well, ia opened, the plunger Is driven up igun 
by the pressure of the air within R R. These thiucs 
it is said by some writers suggested the stmct«« 
of the atmo$pheric enfftnet afterwords invented by 
Newcomen ; yet it does not clearly appear that tUs 
latter person, who was a blacksmith at Dartmoutit, 
in DeT0Dshlre« wu at all acquainted with the works 
of Papin. If he had, it is scarcely posMble ta 
suppose that ho would have omitted to use the Icwr 
safety valve, yet we do nut find it in the enj^ioes of 
Newcomen, a clack valve being tnbstitDtiHl. Ifi 
Savory's engine we have seen that the effect is 
produced in two ways, by the condensation of thf 
steam forming a vacunm in a receiver, into whi^h 
the water is forced by the pressure of the atmoa- 
phere, and where the water was required to b< 
elevated to a greater height than from 28 to 30 flcctt 
he employed the direct pressure of steam of a higher 
temperature and dftn^erous elasticity. In the at- 
mospheric engine, the process is totally difonU 
the steam exerts nu direct action npon the ifSMTt 
or upon any part of the apparatus — it ii mardf 
employed ns a means of forming ■ speedy vacQam* 
under a pisLun attached to one end of a lever* the 
rod of a pump, piston, or plunger being ottaefaol 
to the other end. In this construction the pcnrce 
of the engine has n» reference whatever to the 
strength or temperature of the piston 



L^ 




MAGAZINE OF SCIENCE. 



373 



Uie vBfior is introduMd from the boiler. The 
cjIiDilrr it now fur the 6nt lime doUcfacd 
be water pump. 




I atetm gfnemted in a boiler A, wu admitted 
^ the cork K. into a cylinder C. aoder the 
I ll» attached by a rod or clmin to one end of 
nm L. Tlif other end of the beam bearing a 
hicb is attached to a eommon pomp. A bent 
13 reached from a cistern G, to the bottom of 
rtinder, a aecond pipe reached to the well ; it 
'wn in the figure a> if crossinif the fire. Tbo 
t waa worked by a boj whoie basinets was to 
the handle O hpVwiu-di and forwards. The 
9 moved at the nme time two cocks K and N. 
f which it turned on and the other ofT at the 
time ; now supposing that the boy ptiUed the 
I towards him, it would close N and open K. 
b'aottoo, the steam would msh beneath the 
and driving it up, would suffer the pump 
ft sink, brini^ farced dowo by the weight J. 
I the cylinder is full of Bteam, the handle O is 
d back, and the steam thereby cut ofi*, while 
wk N btnng turned on, a stiram of cold water 
I into the cylinder and condenses the steam ; 
iaton therefore falls, beinff acted upon by the 
in of the atmosphere on tlio upper side of it, 
astfl water runs of by the second pipe. This 
ti Is Ititl naed as a pumping engine, 
f Tn be tviUiHticil J 



PRESERVATION OF HSH, 

cscrring fiib for the purjwses of science, do 
k1 is prefeniblt; to that of immersing them in 
The mouth, gills, and fins can then be 
1 open ; the lays uf the one aud the internal 
of the other ran be accurately examined, and 
the internal rtrucCure of the body may be 
igHted. All these advantages are either parbally 
iUj lost to the naturalist when the specimena 
cither stofTed or dried. It is therefore 
to prevrvr all such species as may require 
t csamination in spirits. Of the vessels 
for fish and other animals, glass boltlra 
the best, as, whati'ver precautions are 
■ portion of the liquor will evaporate tlirouieli 
»«« d wooden caaks : squaru bottka arc to be 



prefeiTvd, as they arraoge doae in caaoa, and no 
spaoe ia lost. The perfect preserrstion of the animal 
depends upon the quality of the liquor, the itianner 
of placing them in ibe bottles* and the method of 
luting or closing these bottles. The following in- 
strucUons under these heada are taken from the 
memoir of the celebrated circumnavigator Peron, 
whose voyages have been attended with more ad* 
vantage to natural aciencethan any others on record. 

The spirituous liquor to be used must be ^m 16 
to 32° of the arvometer of Baume ; (this is from the 
strength of brandy or whiskey, to that of ordinary 
gin,) if it bo stroogcr, it entirely destroys the color 
of the subjects. For qu^mpcds it should be of 
22" All spihlaoufl liqoon are equally good, but 
those which have least color are obviously preferable. 
Before the fish or animal ia put in the Uqnor, it 
should be cleaned from dirt and alime. It is de- 
sirable to prevent it from touching the bottom of the 
bottle, aa. if not supported, it will sink down and 
soon become corrupted. M, Ptron therefore pro- 
poses to fasten the animal to a fiat piece of cork, 
which holds it snipended in the Itqnor. Several 
subjects can thus be placed in the same vessel, either 
by the side of one another or at different heighta ; 
they will fioat in the liquor without touching, and 
the slimy particles will become detached and fall to 
the bottom. M. Peron affirmi that thoa floating 
they cannot be injured, although the bottle may be 
ahajcen or overtumrd- But as this method is not 
very easy, the specimen may be inclosed in a bag of 
very fine linen, or in a net tied to the cork, to which 
*(hey will remain suspended. With vertebrated 
animala it will be advisable to make a amall incision 
in the body, that the liquor may penetrate into the 
inside. M. Peron advises the use of campUorated 
apirita, aa the camphor augments the preserving 
quality of the liijuor. In aome cases, however, this 
is attended with the diaadrantage of making the 
subjects tough and difficult to djaacct. After the 
anicnul has been in some days, the buttle must be 
replenished with liquor, and then firmly closed with 
a cork. stopper : those made of glaas frequently 
break by tiie eTai>oration of the spirits. 

The luting or composition vrith which the cork 
is to be covered, and the evaporation prevented, ia 
called by M. Peron lithocolle; it is composed of the 
following ingredients :^-cammon reain, red ochre 
well pulverised, yellow wax, and oil of torpentine. 
The wax and resin is melted, and the ochre added 
in aroall portions, stirring it briikly at eacb addition 
with a spoon. When the mixture is boiled seven or 
eight minutes, pour io and mix the oil of turpentine, 
and continue to boil the whole. Precautions must 
bfl taken to prevent the infiammadon of tbeie in- 
gredients ; but if this should happen, a Ud to cover 
the vessel must be at hand, with which the flame 
may be immediately extinguished : the vessel should 
moreover be furnished with a handle, and capable of 
oonuining three or four times the quantity of luting 
ibat is actually prcfuiriug. To ascertain its quality, 
a small quantity may be put from time to time upon 
a cold plate, and ita degree of tenacity can thua be 
ascertained. Thia cement ean be prepared at sea, 
and employed almost immediately. After having 
corked Qte bottles, and wiped them well with a dry 
cloth, the cement ia heated to the boiling point, and 
being well stirred, is applied over the whole surface 
of the cork by a brush or any other substitute. 
Sometimes the cement, by penetrating the cork. 
causea the spirits to eva|K>rate and burst the surface ; 
this cauaes amall o|)CDioga to appear, wtucli ore 



874 



MAGAZINE OF SCIENCE. 



•topjted bv pnnnng a iet^nd coat of tithocolle ovar 
the ftnl when it U cold. If the bottlea are sraall, 
the necks ma; be at once plunged into the cement, 
provided the grmn of the cork is of such a dose 
taitare as to prevent anj of the fplrit from pauing 
through durinjc the o|H!ratioii. The aperture of t)ic 
boitle may be further secured by coveriog it a^in 
with Unrn. firioly tied and tsturated with liquid 
piti'h. Bottles tbua prepared may be turned OTer 
in all (Uractloiu, and exposed to the strongest at- 
ninsphenc beat without the least evapomtiua or 
escApe of the spiritn. 

The ikins offish miy be prtserred and dried by 
(Ulferent procevsei. like most simple method, ap- 
plicable to the greatest proportion, is that of dividuig 
the fish longitodinallT, »o as to preserve ooe »ide of 
the «kin and fins in an entire statft ; from this »tde 
the internal bones and Heeh are removed. The head 
JK sufficiently reduced id thickness to admit of being 
Inid flitt ; in other words, accurately divided into 
two : the dorsal ond caudal fins mast of course be 
left entire, as they are too thJn to be divided. Tlwr 
akin and bones being well anointed with the pre- 
servative, may be eitlier filled with plaster and 
attached to a board, or be suffered to dry between 
leivea of blotting paper, and preserfed like dried 
plnnti. 

Ijampreyi, eels, and other cylindrical fiih may be 
preserved by skinning them from the head to the 
tail, in the same manner aa eels are prepared for 
cooldng. The head, however, must be preserred, 
its contents emptird, and the ikin filled with fine 
sand. The diodons, ostrscions, and sevcml oth^^ 
exotic tribes, having their bodies covered with apines 
or bony scales, are to be opened longitudinally under 
the belly ; the interior parts are then remoTed. and 
by being simply stuffed with cotton, the original 
Conn is preserved unchanged. 



GOTHIC ARCHITECTURE. 

Tnt^ term is conaidered by some authors to inrludr 
the Komanrsquc, Saxon, Normnn, or by whnterer 
other name the early Christian style, distin);uishcd 
by its massive character and circular nrcheti, may be 
called; but it is now generally understood as dis- 
tinct from it, and ia thus admirably defined by Mr. 
W he well ;— " It is charflctcriBed by the fointed 
arch : by piUars which arc extended so as to lose hU 
trace of claisical proportions; by shiiftit which are 
placed fide by nide, often with dilTerent tbickncAArs. 
and ore variously clustered and combined. Its 
niQuldings, cornices, and capitals, have uo longer 
Uic c-laaaical shapes and members ; square edges, 
rectangular surfaces, pilasters and entablatures, dis- 
appear : the elements of building become slender, 
detached, repeated, and multiplied; thry oasume 
forms implying flexure and rami^calion. The open- 
ings become the principal parte of the wall, and tlie 
other portions are subordinate to these. The uni- 
versal tendency in to tlte predominance and pro- 
loai;iitioa of vertical Unet.- for instance, in tlic 
interior, by continuiDg the ihafts in the arcfa- 
mouldings; on the exterior, by employing buttresses 
of strung projection, which shoot upwards throngb 
ttie line of parapet, and terminate in pinnacles. 
The jtirr is, in the most complete examples, a col- 
lectinn of vcrtieoi thi\fts surroundiog a pillar, of 
whiL'h the edges are no longer square. The orcbi- 
Tott consist! of members corrc»ponding more or 
less to the membcre of the pier, and c<'ii(k'quently 
is composed of a coUcctiou of ruunds uuU huiluws. 



and loses all tncs of its original rectatieulAr tcoti/n* 

The piers send up vaollinc ''^■-' ' 

independent unity to tht.* t' 
bound: and the clerestory ^\.... 
puniment have a necessarr relatmn to tnt* vymmrtry 
of this com{Hirtment : the tnforium of oohpm* ro&* 
forms to the same rule. At the same time, tliff 
workmanship improves much, both in skill 
taste, and carries the predominating character 
the details." 

But all these changn were introduced gndual^ 
in tlie course of sereral centuries, and Uio GnOtiif 
style has, consequently, been divided into ibi 
diatincl periods. The fir&t style of Gothic in this 
country, called by Mr. Rickmnn fhe Mfly En;'liiK, 
prevailed throughout the thir 
decorated style, or peKect 1" 
the greater part of the fouri^iun ctinur; 
third and last style, called by Mr. Rickmi 
perpend icuhir, may be called the iiylc. of 
fifteenth century; hot specimens may be found m 
late as 1040, and even later, though oftm natk 
debased, and mixed with the Itahan style, 
prevalent. 

It has been well observed by Mr. >ViI1is, 
complete Gothic style did not arise at oncfl. 
the Romaneatjue ; but that, on thr ■ ■•■ 
is in every country a diflcrcnt iw 
which has been called early Gotli- 
aubstilute the name of each rountrj as a >: 
thus wo have early English, early Get.- 
French, and we may add, esriy Italian, in, 
the Gothic Wds at once superseded by the 
Claasical, but in other countries it had 
decline into formi which may be termed tbcj 
Gothics, and which in Germany, the Nelbri' 
France, and England, conititutc as many 
styles, although derived from a common 
]n the two latter they have bcrn termed flont 
and perpendicular, from the foruis of the (i 
the windowi, and were sU rvenluiUly so|' 
the revived Claasical. which spread itcdi 
over the wbolo of Europe. 



Hfl* 



INERTIA. 

Inbktia means possivenesa or inactivitr. 

matter is, of itself, equally incspnblc •• 
itself in motion, or of bringing itself to 
iu motioti. 

It is plain that a rock on the mrface of the rofli 
never ebunges its position In respect to other 
on the earth. It bos of itself no powct to 
and would therefore for ever lie still, unIrM 
by some external force. This fact is pn?' 
(■xperieoce of every person, for we »rc 
objects lying in the same pohitioni all uim u>ri. 
Now, it is just as truti that inert mittrr has du 
power to bring iteclf to rest, when once p«t in 
motion, as it is. that it cannot put itself In metiofc 
when at retil ; far, huving nu life, it it prrfbfth 
passive, both to moliun and rcjl, and 
either state dejiends etiUrely upon exlisni<L: 
stances. 

Many instances might be given of Um unwUlint- 
ness of matter to yield to any tm|M' - » to 

it, and its tendency to remam (jtiir ••' IM' 

lowing are among the most iofitrucu.. .;i U» 

sails of a ship are loosened to the bircax, slimtf 
and heavily at first the tckmI gets into motioflt bet 
gradually its bpccd increases m^ the force by wkirk 
it is iuipdled overvuraca lh« inertia of Uu 



ita^blil 



MAGAZINE OF SCIENCE. 



S75 



^^ force is DcecAsary at first to Ml a Tchiolc in 

■vtinn ; but when once thii !& eireoted, it goes on- 

wtA witTt r<ini|>Arfitivc taic, fu Ihftt, In fact, a strong 

fffbrt 1b nccesflary beCoro it can be slopped. If « 

per»(in be stuiding in it when it Is saddenly set 

«»g<*1ug, bis feet ar*; palleJ forward, whilst his body, 

•b«7tng the lnw of ioertia. retnains where it whs, 

Old be accordinj(lr falls backwards. On ibc other 

JUnd. if the vehirle be aaddenlT stopped, and the 

individual be standing in the samn position as 

Ibn&rrly^, tb« tendency which bis body has to more 

forward — for it actinired the same motion as the 

carriAge by ffhicb it was borne alung— will oaute 

Um to fall in the opposite direction. Casuntties of 

description frequently occur to persons on 

konieback, wbo are thrown over the necks of their 

or ftttl behind them, according as the animal 

■ I Huddeolr, or stnrtfi off unexpectedly. A. 

I'ini; from a coach at full s|>ced will cer- 

iviii:iiy till prostrate on the groaitd, if he leaps down 

mm if he wcr« drxcending from a body at rest, to one 

l-nliii '^ tri in ttic same state ; for when he makes the 

1 is body has the same motion as the coach : 

[ L the fret arrive at the ground, the motion 

ta the lower piirt is arrested, whilst It continues in 

the upper part ; snd thus be finds himself thrown 

from tin! perpL'odiculsr iuto the borizoutol position. 

The following; is a familiar example of the inertia 

■of matter : — L'pon the tip of the finger let a card 

bf HahiDred, and a piece of money — say a shilling 

—laid upon it, Let the card then be smartly struck. 

nd it will fly from beneath the coin, leaving it 

npported upon the finger. Thia arises from the 

laerlia of the metal being greater than the friction 

of the card which passe* from beneath it. 

Conning, or hsrc-bunting, affords a striking 
ninatration of inertia. In that cruel sport, tlie hare 
Co possess an instinctive consciousness of the 
ee of this law of matter. When pursued hj 
grvyhoand, it does not run in a slraigbc line to 
Che cover, but in a xig-zog one. It dnnble*, that is^ 
■Dddcnly changes the direction of its course^ snd 
tarns back at an acute angle with the direction in 
which it had been running. The grryhound, being 
onprcpared to make the Com, and therefore unable 
Co rr*t»t the tcndrncy to persevere in the rapid 
motion which it has acquired, is impelled a con- 
nderable distance forward before it can check its 
and return to the pursait. But, in the mean- 
Ibe hare has been enabled to shoot far ahead 
other direction ; and althoagh a hare is much 
rt than a greyhound, by this scientific ma- 
g it often escapes ita pursuer. Those who 
witneued the [lerhaps still more cruel practice 
of horsc-rucing, may have observed that the hones 
shoot far past the winning>poat before their speed 
C4n be arrested. This is also owing to the inertia 
of their bodies. 

Common experience proving Uiat matter does not 
put itself in motion, we might be led to believe that 
rest is the natural state of all inert bodies ; bnt s 
few considerations will show thst motion is as mach 
the natural state of matter oa rest, and that either 
state depends on the resistancef or impulse, of 
cstemal causes. 

If a cannon-ball be rolled upon the groond, it 
g-will soon pesse to more, because the ground is 
rough, and presents impediments to its motion ; 
but if it be rolled on the ice, ita motion will continue 
much longer, because there are fewer impediments, 
Rnd, confiqueotly, the same force of impulse will 
nrry it oaucit farther. We see from this, that, with 




the ssros impnlse, the distance to which tjie ball 
will mov« must depend on the impediments it meets 
with, or the resistance it has tu overcome. But 
suppose that the boll and ice were both so smooth 
as to remove as much as possible the reustsnco 
oaased by Metion. then it is obvious that the boU 
would continue to move longer, and go to s grrster 
distance. Next, suppose we avoid the friction of 
the iee, snd throw the bsU through the air, it would 
then continue in motion still longer with the same 
force of projection, because the air alone presents 
less impediment than the air and ice, ami thrrc is 
now nothing to oppose its constant motion, except 
the resistance of the sir. 

If the air be eshauated, or pumped out of s vessel 
by means of an air-pump, and a common top, with 
s small hard point, be set in motion in it, the top 
will continue to spin a considerable length of time, 
because the air does not resist its motion. A pen- 
dolom, set in motion in an exhausted vessel, will 
continue to swing, without the help of clockwork, 
for a whole day, because there ii nothing to resist 
its perpetual motion hut the small friction at the 
point where it is suspended. 

We see, then, that It is tha resistance of the sir, 
and of frM^ou, and of gravitation, which canses 
bodies once in motion to cease moving, or come to 
rest ; and that dead matter, of itself, is equally 
incapable of csnsing its own motion, or its own rest. 



IMITATION OP COGNIAC BRANDY. 
^English spirits, with proper msnogement, sre 
convertible Into brandy that sfasll hardly be dls- 
Uinfuishcd from foreign, in many respects, provided 
the operation is neatly performed. The best, and 
Indeed the only method of imltsting French brandies 
to petfectign, is by on essential oil of wine; this 
being the very ingredient which gives the French 
brandies their flavor. It must, however, be re- 
membered, that in order to use even this ingredient 
to advantage, a pure tasteless spirit must first be 
produced ; fur it would be absurd to expect, that 
this essenttol oil should he able to g^ve the agreeable 
flavor of French brandy to our malt spirit, ulrcadj 
loaded with its own oil, or strongly im|>ret{nated 
with a Uxivtous taste from the alkaline salts used in 
rectification. 

To prepare the oil of wine, dissolve some cakes of 
dr> wine-lees in six or eijht times their weight of 
water, distil the liquor by a slow Are, and separate 
the oil by a sepnrntory glass, reserving for thrnicest 
uses that which comes over first, the succeeding oil 
being coarser and more resinous. This oil of wine 
may be dissolved in alcohol ; by which means it will, 
for a long time, be fully possessed of alt its flavor; 
but otherwise it will soon grow rancid. 

The essential oil, however, most be drawn from 
the same kind of lees aa the brandy, to be imitated, 
waa procured from : that is, tn order to imitate 
cogniuc brandy, it will be necessary to distil tha 
essential oil from cognise lees ; and the samafbr any 
other kind of brandy. For as different brandies 
have different flavors, and as these flavors are en- 
tirely owing to the essential oil of the grape, it would 
be preposterous to endeavour to imitate the flavor 
of cognioc brandy with an essential oil procured from 
the lees of Bourdeaux wine. After the flavor of the 
brandy is well imitated by a proper dose of the es- 
sential oil, and the whole reduced into one aimplo 
and humogeneoos fluid, other difficulties still remain: 
the color, the proof, and the aoftneu, mut aIm bo 



MAGAZINE OF SCIENCE. 



regu-Jed, before a spirit that perfectly resembles 
brandy c&a be procured. \^'tth regard to the proof, 
it may be easUy accomplisfard. by mini? a spirit 
rectified abore proof; this, after being intimately 
combined with the catenttal oil of wine, may be 
reduced to a proper standard by diitiUed water. 
The aoftneas may, in a great meaaure, be obtained 
by difltilling and rectifying the spirit over a gmtle 
firei what is wanting in this criterion, when the 
spirit is fint made, will be aappUed by time : for 
it roust be remembered, that it is time alone that 
gives this property to French brandies, as at first 
ihcy are acrid and fiery. Treacle, or burnt su^or. 
gives t)ie spirit a tine color, nearly resembling that 
of French brandy ; but as its color is deep, a large 
quantity must be used. This is not, however, at- 
tended with any bad consequences ; for notwith- 
standing thst the spirit is really weakened by tliis 
nddition, yet the bubble-proof, (the general criterion 
of spirits,) is greatly heightened by the tenacity 
imparted to the liquor by the treacle. The spirit 
acquires from the mixture a sweetish or luscious 
taste, which renders it very agreeable to some 
palates. A much smaller quantity of burnt sugar, 
than of treacle, will be sufficient for coloring the 
■ame quantity of spirits: the taste also is very 
diflerenC; for, instead of the sweetness imparted by 
tlie treacle, the spirit acquires from the burnt sugar 
an agreeable bitterness, and by that means, recom- 
mends itself to many who dislike a luscious spirit. 
The burnt sngar is prepared by dissolving a proper 
quantity of sugar in a little water, and scorching it 
over the fire till it acquires a black color. ^ 

The spirit distilled from molasses, or treacle, is 
Tery pure. It is made from common treacle dis- 
solved in water, and fermented in the same manner 
as the wash for the common malt spirit. But if 
some particular art is not used in distilling this 
spirit, it will not prove so Tinous as malt spirit, but 
more Hat and less pungent, though otherwise much 
better tasted, aa its essential oil is of a less offensive 
flavor. Therefore, if fresh wine-lees, abounding in 
tartar, are well fermented with molasses, the spirit 
win acquire a greater vinosity and briskness, and 
approach much nearer to the nature of foreign 
brandy. If the molasses -spirit, brought to Che 
common proof-strength, is found not to have suf- 
fieient vinosity, it will be proper to add some sweet 
■pints of nitre ; and if the spirit has been properly 
distilled by a gentle heat, it may, by this addition 
only, be made to pass, with ordinary judges, as 
French brandy. Great quantities of this spirit are 
in adulterating foreign brandy, rum, and arrark. 

[uch of it is also used, alonci in making cherry- 
brandy and other cordials by infusion ; in all which, 
mitny, and perhaps with justice, prefer it to foreign 
brandies. Molasses, like all other spirits, is eu> 
tirely colorless when first extracted ; but distillers 
always give it, as nearly as poaoible, the color of i 
foreign spirits. 



PEEPARATION OF PYROLIGNEOUS 
ACID. 

Puict ft loife cajt-iron oylinder. or retort (similsr 
to thoae used for the. production of carburetted 
hydrogen gos.) in a furnace, so that it may receive 
ai mncJi heat, all round, as postdble. One end of 
this cylinder must be so constructed as to open and 
■hat, to admit wood and exclude the air. 



Oak in pieces about a foot in length is to be pal 
into the cylinder, which is to be tilled as fall as 
possible, without being wedged, and the door nutt 
be shut dose to exclude air. From the cyltader l*t 
a worm run through cold water to condense thp 
acid ; by this it is conveyed to a large cask placed 
on one end where there is a pipe to carry it tnm 
thot to two itr three mure i thus it is completely 
secured from flying off in the vaporons #t.-'- T'-- 
fire is now to be raised to a great heat, ■■ 
powerful to fxinvert the wood oomph' 
charcoal. When the acid ccaaos to come over, tiw 
fire is to be taken out, and the moss of wood leA (n 
cool in the confined state, when it becomes perfect 
charcoal. In the first cask tar ii chiefly cont4la«d 
with the acid, it predpitatea to the bottom, and b 
drawn off by a cock ; it is afterwards boUcU io to 
iron boiler to eraporata the acid, before it is fit for 
use. If the acid is not strong enough, it is put iato 
large square vsts about six inches Seep, for ihc 
purpose of making a large surface, to ersporabi s 
part of the water contained in the acid more speedily 
by a stow heat. These vats are bedded on aiai 
upon the top of u brick stove, where a gentle Imt 
is applied ; thus it may be procved in a pretty 
strong state. 



MEMORANDA. 



3 

thel^H 

nd whoiV 

-I . r 



7b 7Vanjj/pr EngraringB Io Ptaster Catt^ 
the plate with ink, and polish its surface in the 
way, then put a wall of paper roood it, and 
completed, poor in some finely powdered pUitfTvf 
Paris, mixed in water; jerk the plate repeatedly. to 
allow the air bubbles to fiy upvrards, and let 
stand one hour, then take the cast off* the plate, snd 
a very perfect impression will be the remit. 

Spotn on the Sun, — Hertchel supposes the spots 
in the sun are mountains on its surface. |icrUa]it 
above 300 miles high. On examining the ran 
several powers from 90 to SOO, tfae black apota 
seemed the opaque ground or body of the sun 
the luminous part an atmosphere, interceotod ii 
broken. If one of the spots appears npoa the 
ern limb or edge of the snn's disc, it morea tbenn 
to the wefltern edge in 13^ days ; it then diaappaaii« 
and in about 1^ days more, is seen again upon ibe 
eastern edge; and so continues, completing \t9 
revolution in about 27 dsys. In 1779, Hendtd 
measured a spot in tlie sun riO.OOO miles in diameter. 
These spots cross the sun from eost to west, and 
show that the axis is inclined 3^ 4S' to the eastward 
Spots have been seen to divide andseparKte in many 
parts. They frequently make notches hi the sun 
limb. When they disappear, they are succeeded b| 
facnlK or bright spots. They are clasaed as openingt, 
aballowa, ridges, nodules, corrugations, indentatlona 
and pores. 

Daily TVfflpera/vre. — The mtan daily comse 
the temperature of the atmosphere is the nme 
all hours. According Co a yearly mean the cold 
hour of the day in Europe is 5 o'clock in the mom 
iug. Tlie warmest hour of the day is from 2 to 
in the aftem<^on. The rise is most considenhl 
some boars after the minimum, the foU oome hour 
after the maximum. The beat increases for 9'1I 
hours, decreases for \i.\h hours. The grcfttea 
dsily range of temperature in Europe is about 30^ F 
The greatest daily range of temperature in Eorop 
takes place in July, and the least in December. 



lAKDoa^— Prlo^ad hv D. Piahcu, «. \Vhlt« Honw Une. MlU Eod — Pobliibwl by W. Bomafw, II, 
SdlaboTib. J. MoKsm.— Glasgow. D, Biici and J Basksi.— livcrpool. G. Paiiir. 



Row. 




AGAZINE OF SCIENCE 



ana Scftooi of am* 



did. 




BATES'S ANAGIATTOGUAPHY; OR, MACHINE FOR MEDALLIC 

ENGRAVING. 

Ml. lU.— NO. XLVIIl. 



378 



MAGA2INE OF SCIENCE. 



B\TES'S ANAGLYPTOGRAPHY: OR, 
MACHINE FOR MEDALLIC ENGRAVING. 

Thb object of this iuvention is to produce bdogv* 
engravingt), or correct rcpresentatioriB of biuu, me- 
(l«ltioits, tncdaU, «*als, or other objectA in relief, on 
H plftin sarface, tn a more correct and perlect manner 
than has hitherto been donf by trucinR; or cngmTin5 
mncliincs ; and is particularly dcai|:ned to prevent 
tlta distortion of the features of the bufit, or of the 
lubject to be copied, at the samR time producing the 
desircil effect, to rcprcKot a subject in relief. Pig. 
1 , reprvKnta a side cIcTation uf these improvenirnti 
on machinery applicable to the imitiition nf mcduli, 
acnlpture, and other works ofartexecuteil in relief: 
A A, rcpr^Ecnts a board or table; and U, show* a 
vertical «ertion of a braai locket fixed thereto; L'. 
is a aqoare brats standard, made to slide up and 
down within the socket, being very accurately titled ; 
D, is a steel screw, having a micrometer attached at 
its lower end, by which means it can be turned so 
aa to move the standard C, at equal distancea, cither 
ascending or descending ; E, shows a plate of metal 
fixed to tlie standard C, and inclined to the hori- 
Kontal plane of tbc table or hoard A A, at an angle 
of 45''. The npper edge of this plate has a groove 
formed in it, to receive two bevelled rollers of a 
carriage now to be described ; P, represents u cor- 
rugc, which moves very freely on the plate E, by 
means of three frollers, two of which are beveltcd, 
so as to enter the groove formed to receive them, on 
the npper edge of the plate E. In this view, only 
one of the bevelled rollers A, ran he seen, the other 
being immediately behind it. These rollers are made 
with long axes, and very accurately fitted in their 
bearingn, so as to move freely wilhont shaking. 
The lower part of this carnage is supported, and 
moves on a single roller B, the axis of which is 
placed at right angles to those tlreody described, 
the periphery revolving and resting upon tlto ledge 
C i D, represents a sliding plate, which is made 
very trae, and parallel on two of its edges ; and 
these are bevelled on each side, so as to produce a 
double prism ; the bevelled edt^ea ko formed enter 
the grooves of four rollers, fixed in the carriage P. 

By these roeans the Hliding plate II U, U made to 
move very freely, and yet with great accurncy ; P, 
represents a point, fixed to the sliding plate D D ; 
this is used to trace over any medul, or other suit- 
able work of art that is required to be copied ; G, 
shows a section of a portion of a sphere, rising from 
a phme surface, and similar to a medal in ita 
geucrul furm. Any such subject may be fixed to 
the supporting frame II, by any suitable cement, 
care being taken that its plane be placed in a proper 
position i I, is a metal guide, fixed at its lower end 
So the sliding plate D ; the upper portion of thii is 
formed into a straight edge at G, and stands per- 
pendicular to A A ; 1, represents a vibrating lever, 
the arms of which are equal ; this swings freely on 
two conical points, one of which is ?tcn in the arm 
fixed npoo the carriage P. The upper end uf the 
vibrating lever has a friction roller placed in it. 
which ia always kept in contact with tlte straight 
edge of the guide G, by a spring, while the lower 
end of the lever moves the frame M, at the end of 
which the diamond point is fixed, as shown at J, 
periirtidicular to the surface of the oopprr-platc N, 
whuh lies parallel with A A. 

One end of the point frame M, is jointed on ench 
wiAt to the lower end of the vibrating lever, forming 
•b «lbow joint Uicrcwithi the pivoti or beariogs 



hiaag madjD oonicdt so as to avoid fnett^n as suali 

as possible; P, represents a small '' ' 

an axis, oue 'end of which turns t 

projecting arm, and is retained in i 

friction ; the other end h.is a tUt h^r 

it, by which it may be turned : R. 

Bilk 'cord; one end of this is ooiled 

barrel P, and the other is attached to tha 

frame M. 

By these means tlie diamond point may b« i 
from the plate, and kept suspended at 
X, represents the plate carriage, which 
friction rollers pla(^ in firames under It. 
these rollers are bevelled, and run in i 
formed in an nnderplate : the other roller is pi 
and rolls on the surface of the aume metal 
There is a cord made fast at one end to the 
and passing over the pulley N, it haugs 
has the weight O, appended to it ; by vbleh 
the carriage will be drawn along whenerer 
lowered by the micrometer screw D. 

When this machine is to be used, the roirromrt» 
screw D, should be placed in the centre of 
and then the medal, or other object to - 
over, must be placed at such a bright thai tbe 
point F, may be brought just in c/tntdct wit 
centre of tiie medal; the copper platt N most 
samo time be placed immediately umJ'T the di 
point, with its edges parallel to the pljte X. 
machine and plate being tltus adjusted, the 
meter screw D, must be made to raise the at 
C, and all the parts combined therewith, ont 
tracing point P, will nearly rejich the top i 
medal or other snfaject. The tracing point F*1 
then be laid hold of by the band, and brot 
rnntnrt with the surface at S, {moving the 
1), as may be re<{uircd, to bring the tracing 
into its mean position,) by means of the eoc 
motions of D and P. The machine will tbea' 
the proper position for bcginoinK the firit Knf,^ 
the button must be turned, and the 'tnmond 
gently let down upon the eo]tper y\tiu- 
tracing point F, being then passti 
over that part of the medal which ; 
it, the diamond point will be fouml 
a Hoe on the copper plate, exactly < 
the undulations which the tracing p : 
over on the medal. The difimond pouit 
be raised from the plate, and the mieroni 
must be turned, so as to produce ouch a i^uu 
between the lines on the copper plate as may have 
been previously determined upon, and ' 
movements repeated, until the whole sun 
medal has been traced over. Whrn an- 
other works of art are to be traivd ov< r 
undulations of the tracer transmitted to 
as to produce a copy thereof, such wor% - 
placed before the tracer P, in a vcrticiLl , 
and the mode of setting and adjusting the uu<-Lit;f. 
and also the copper plate, most be adopted. II 
before described ; and then if the i : 
to pass over every part that the V t 

reach, such andulation vrill be trai.. . tsj 

copper plate, and a correct representation wtB 
the result. 

Pig. 2. represents a front view of Pig. 1 , tha 
letters of reference being pUoed npon tha 
parts wherever they con be seen. T' 
standard is omitted, and also the i 
by which It is moved. In fom> 
the tracing point is moved in a pl« 
10 the pUae of the nedil. Now, i.. 



MAGAZJNE OF SCIENCE. 



379 



a, tho trsciii; fHMitt moves in a pUne 
9 tiw pirtue of tbe mwW, or, in other 
iquo tu tlie plane in irUitili C mute* ; arid 
iple of the correetitiu couaJits ia muking 
l»eribed upon the copper (which i« etraigbt. 
the txacer (Iriuiriljci the plnite of the 
bveomeB Hivertrd from the stniight liue, 
F rises abuvc ttiis plftne), be diver led nit 
Btiiy froui Ihr ulraiglit line upon the cup- 
tnccT is diverted frum i plane perpeo- 
I kho |i|Bite of the nitrdal. The rrtalive 
the oiolions rt^uircd to prodace thta 
f be dof-ribfrd by any right-angled iriangle; 
1 heiiii; ill tUc jiUne of the biL»e, a Kuoud 
le of ihr perpeiidicul.u, and a third iii the 
hr hvpoiticnuitr, or tn planei parallel to 
jj]itrtr» rrApectitreljr ; and the propor- 
pftretit citnraiion iu the eugraring will be 
n in the medal iteelf. us the proportiuo 
mi the triangle to its perpeodicular. 

let, 3, 4, 5, the moLioQ reprnaented 
effected in the machine by the edge y ; 
d by A C» ia eB'ectt^d by the aJtding 
and the motion represented by B C, is 
B plane surfai-e N ; also in Fig. h, where 
perpendicular are equal, the engraving 
aa much elevated oa in the medal itself : 
where the base ia half the perpendicular. 
Ting will appear to have only half the 
a of the medal ; and in Fig. 3, where the 
donble the perpendicular, the engraving wtU 
have doable the elevation of the medal. 
Uteatee coorludes by saying, " I hereby 
" at whether the machinery or apparatus, 
Iheligurvs that is used to shift the tracing 
' distances, moves either vertically, hon- 
or in any other direction, my iiivonlion 
making the tracing point move and 
poo tlie medal, or other work of art, in a 
ue to such motion, that being the prin- 
my invention differs from all other 
DOW used for producing similar effects." 
uwell beubacrvvd, that the title page of 
nary of Arts and Scriencca," is an illoe. 
I this method of engraving; indeed, it was 
)by tlie vciy oiachiue now described. The 
BDpper or sltci has on etching ground hud 
the lines are then drawn as described, tod 
■re bitten in, as iu etching. — £0.] 




BUTTERFLIES. 

n butterfly Is a literal translation of the 
wd, BuHtr-fieozCf and is supposed to be 
use the insects first become prevalent 
auing of the aeaaoa for butler. They 
from the other scaly-winged kinds, 
tntenao: with a knob or club at the 
holding their wings, when in ■ ftote 
\f erect or very slightly iovlined. They are 
generally and familiarly known of our 
ibcs, and by their conspicnoua appear- 
loD h\[ to attract the notice of even those 
Mptious are least alive to the beauty of 
Ifecta. The graceful curves of their out- 
Lr gay and fitful aight—tlie splendor of 
iring and decorations, which present every 
r tint found in the dilTcrenC kingdoms of 
itstribuled in markings and deltneatious of 
beautiful and diversified character, ftecm to 
I Ihem a kind of superioiity over other 



buttifrflies are very auinrroas in s|)eciea, although 
bnr. A litniteil number Inhahit this country. Between 
2000 oud 'Syi\)^y have I*e«u described, and it is pro- 
bable that no iucoiuiderahle nnmher yet remain 
tmdisoovert'd. About 7.'i diiTrrcnt spttiiea are re- 
curded as indijjcnous to Uritaiii. A g^eat proportion 
of the largest and most highly onuimented kinds ure 
nativea of the new woild, eapeclnUy of Bra»l ; hut 
they abound in all tropical eonntries, and ttonoe of 
thcM! esotic« present the most sumptuous fJLamplei 
of insect beauty. Although our British butterfiiea 
can in no way compete with the mogoiltcent examples 
ju«t referred tu, we yet possess many of great bennty, 
whether as regards the bnlliancy of their color, or 
the Jiarmonioui manner in which theac colors are 
liistrihuted. The bluish-parple rcflecuon that plays 
on the wings of tlie emperor of the woods, haa i 
richness and brilliancy of tint, which ia not often 
aurpasaed. The mode of paiuting employed tu 
produce these rich tints, may not improperly be 
called a kind of natunil mosaic, for the colors ia- 
variably rntide in the scales, which form a denia 
covering over the whole surface. These scale* ttra 
usoally of an oval or elongated form, and truncated 
at the Lip, where they are occasionally diriilod into 
teeth ; but someUmea they are conical, linear, or 
triangular. They are fixed in the wtng by means 
of a narrow pedicle, and are most eommnnly dispoaed 
in transverse rows, placed close together, and over- 
lapping each other like the tiles of a roof. In some 
instances, they arc placed without any regular order, 
and iu certain cases there appear to be two layera 
of scales on both aides of the wings. When they 
are rubbed off, the wing is found to oonslst of an 
elastic membrane, tlan and transparent, and marked 
with slightly indented Lines, forming a kind of groov* 
(or the iniertioD of the scales. The latter ire so 
minute that they appear to the naked eye like powder 
or dost, and «e they are very closely plaeed, their 
numbers ou a single insect are astonishingly great. 
X>et!uwcnhock counted upworda of 4D0,0U0 on the 
wings of the silk rootb, an ioMct not above one- 
fourth of the size of some of our native butlcrflies. 
Uut how much inferior must thia number he to that 
ueceiisary Iu form a covering to some foreign butter- 
flies, the wvugs of which expand upwards of half a 
foot ; or certain species uf moths, some uf whieb 
(such aa the atlaa moth uf the east, or the great 
owl moth of Bi-azit,) sometimes measure nearly % 
foot across the wings. A modern mosaic picture 
may contain R70 tesseruUe, or separate pieces, in 
one square inch of surface ; but the same extent of 
a butterfly's wing sometimes consists of no (ewer 
than 100,730. 

In common with several other extensive racea of 
insects, butterflies derive their nourishment entirely 
from liquid substances, and the structure of the 
mouth is consequently very different from that of the 
masticating kinds. They are hence classed among 
the hauRtdUlcd or suctorial tribes of insects. Tho 
most conspicuous and elaborately constructed organ, 
is the long flexible tube projecting from the inoutli, 
which fonns a coiuU through which the alimcutary 
jnicea are absorbed. This inittrumeut, which is some- 
times of great length, is spirally convuluted when 
unemployed, but it can be unrolled with great ra- 
pidity, and ia admirably fitted to explore tlie tubulsr 
ooroUas and deep-seaterd nectaries of flowers, for the 
pnrpoae of extracting their sweet secretions. It is 
of a cartilaginous sobstonce, and owes ita great flexi- 
bility to its being composed of numerous rings or 
tf intYene fibres, besriog some reecmblance to Iha 



380 



MAGAZINE OF SCIENCE. 



annuloM stracture of earth-wormi and Home other 
■nimiils. It is formed of two distinct pieces, whirli 
odioU of being Br(>3rAtcd throughout their whole 
length. Each of tlieae pieces U traversed tonpta- 
dinstiy by a cytiDdrical tube, and bcin^ grooved on 
their inner suie, thry form when united nnother canal 
in the centre, of a somewhat equare form, and wider 
than either of the two lateral onei. The junction 
ot the two parts is » close that the inclosed tube 
is perfeotlj air-tii^ht; and this union ia effected by 
means of on infinite number of fillets, resemblinc; 
the Umino! of a feather, which interlace and adhere 
to each other. Of thete three tubes, the central 
one alone serves for the inHux of the alimentary 
fluids, the two lateral ones being probably employed 
in transmitting air in aid of respiratiout which, how. 
ever, is mainly carried on by means of stigmata or 
lateral pores. The outer extremity of the proboscis 
ia frequently beset with many membranous papUlie, 
resembling leaflets, which have been regarded by 
some authors as absorbents. From having observed 
them chiefiy in long and sirnder trunks, Reaumur 
was led to concciTe. that their only use is to render 
that organ more steady, by affording numerous points 
of support, and adhering in some degree to the sub- 
stances into which it is inserted ; — an explanation 
rendered highly probable by the fact, that the long 
and slender oriposliors of Ichneamooa, and many 
other insects, are generally provided with some 
pointed projections near the tip, evidently intended 
for this purpose. 

Bath the different kinds of eyes which occur 
ftinODg insects arc to be found in the butterflies. 
The ordinary, or compound eyes, are largo aud 
hemispherical, occupying; greater part of the bead, 
fend no fewer than \7,'i2b lenses have been counted 
in one of them. As each of these crystalline lenses 
poaseasea all the properties of a perfect eye, some 
butterfiies may therefore be said, if M. Poget's ob- 
Bt^rrattons ore correct, to have no fewer than ;t4,650. 
The stemmatic, or simple eyes, in the form of pel- 
lucid spots, are usually two in number, and placed 
on the crown of the bead. They are probably often 
wanting, and, when present, are so iodistlnct, from 
being covered by the hairs and scales that clothe 
the surface, that their existence in any cose among 
butterflies has been sometimes denied. The antennsr 
arc of moderate length, and consist of a great number 
of joints, which asoally hicrease in thickness towards 
the extremity, where they form n dub or knob. 
They are greatly more uniform in appearance and 
structure than tu the coleopterous or most other 
tribes, or in the nocturnal species of the same order, 
which often have them beautifully branched and 
plumose. 

The thorax — that portion of the body intermediate 
between the head and abdomen — ia composed of 
three segments, so closely united as opparently tu 
form a single piece. Its most ordinary form ap- 
proaches to cuhirol, Ruy apparent deviation from that 
shape being chiefly caused by the greater length and 
density of the hairs and scales with which it is 
duTcred. Before the insertion of the upper wings, 
two oomeous scales may be observed, covered with 
tufts of hairs, so as to make them resemble an 
epaulet ; those htirc rrceived the name of patagia, 
or tippets. The scutellum — a triangular piece in the 
hinder part of the thorax, which is very conspicuous 
in beetles ond many otlier tribM — likewise exists in 
butterflies, but is vpry minute, and has its point 
directed forwards. The thorax is always shorter 
thMO the abdomen, and generally more robust, as it 




eJipmni 



supports all the organs of motion, and contaioa Ibi 
muscles by which the latter are actuated. 

Thcuc important appendngci are of ooone thi 
wings and legs, of which it is necessary 
account. The latter, aa in all other geual 
are six in number, and composed of the 
of pieces as in most of the class. They are 
pretty close to each other, without any inct 
the size of the intervening spaces. Tlus c| 
often fringed with long hairs, and the (ibis 
quently armed with a spur near the middle, 
others at the lip. The tnrsi in all the pctfe 
are five-jointed, and furniBhed with two dawsl 
extremity, which are often bifid. Many of 
insects, however, have the anterior pair 
imperfect, or not adapted for walking, belnf 
short to reach the plane of position, and asnall] 
drawn close to the aides of the t> Iua| 

hairs of which in a great measure c<- 'nm 

our view. These spurious legs have ijiw> uhl ^oiol 
in the tarsus, which in some cases (as in ranea^gf Acj 
is without claws ; and the species so circumi 
are named tetrapod, or four-footed buttci 

The wings are of much greater extent, in 
tion to the size of the body, than iu any oth( 
of insects. The forms which they assume arflj 
various; but t)i« most ordinary shape of the 
pair is triangular, with the apex of the 
towards the body, while the outline of the 
wings approaches to circular. Tlu'y are (ravi 
by numeroos nervurca, which give a great d 
strength to the wing, and hold in tenaioa ' 
elastic membrane of which it is composed. 
uervures are tubular, and are permeated by ani 
and aqueous fluid, the action of which 
wing when in a moist and corrugated state 
insect has emerged from the pupa. The 
branches rise from the point where thi 
attached to the body, and they divide towi 
other extremity into numerous ramihr-tDOoa. 
spaces into which the wing is divided by thesaj 
rures.are denominated areoleta byKlrby and S| 
and these authors regard the upper wings asi 
into three larger longitudinal erctions, wt 
term areas. The costal area occuptea 
margin : the anal area, a narrow spaoa< 
posterior margin ; and the intermediate i 
part of the vring lying between tl»e two 
moat conspicaoQB arcolet in butterflies la 
the centre of the wing, at the base, and is 
closed on its outer side by transverse nei 
many instances, however, there are no 
nervnres, and all the areolets are open tAi 
outer side. 

With such an extent of " sail-broad vsns,* 
easy for butterflies to support themselves for 
time in the air ; but their mode of flight, i 
Reaumur'a opinion, ia generally not very 
They seldom fly in a direct line, but 
rising and falling altematf-ly, in a sac 
zags, up und down, and from side to udo.' 
in this manner, tliey are supposed 
easily the pursuit of the smaller birds, 
make them a prey. " I one d«y i 
pleasure,'* says Keaumur, ** a sparro* _ 
butterfly on the wing for a considerKble timr, 
succeeding in catching it. The flight of thtf ! 
was notwithstanding much more rupid than' 
of the butterfly, but the Latter was alwsyi 
above or below the point to whicii the bird di 
its flight, and at which it expected to 
Many of the species, honevcr, dtflcr so 



to 



MAGAZINE OF SCIENCE. 



J8i 



|tf in their mode of flyio^, that a prACtiaed 
reoo^uc tbctn by thU means nlonc. Soch 
tDTided with ft^on^ nin^s, excrci»e m more 
ndcuntinuous flight, nearly resembling tbil 
0, ftAcenditig high int;> the air, and often 
Iheir way aj^ainst a pretty strong current uf 
Df OUT Briiitb species, the white admiral is 
K celebrated fur tti mtuiner of flying. 
Pnder section of the body is the abdomen, 
nts nothing peculiar in its Turin or 
It consists of six or seven segments, and 
to the posterior part of the tboru by a 
portion of its diameter. It is without 
doge at the extremity, there being nothing 
|p a ating or ovipositor among butterdiea. 



ICAL COMPOSITION OF COLORS. 




Carbonate of lead. 



Oxide of line. 
Ditto of tin. 
Ditto of bismuth. 
Pulverised pearls. 



... 1 Carbonate and sulphate 

'^'^ I ofbarytes. 



obre. 
tto. 






Ditto of lime. 

A compound of tlie oxides 

of lead and antimony. 
Protoxide of lead. 



Ditto of iron and earthy 
matter. 



■JIIW. 



Vbiod. 



From the root. 
Gum resin. 
Uriophoaphate of lime. 

Bisulphuret of mercury. 

Peroiodide of ditto. 

Deutuxide of lend. 
1 Peroxide of iron & earthy 
J matter. 

Gum resin. 
1 Brazil wood, gam lac, 
J coccus. 

From the root. 

From the coccus cacti. 
\ Silica, alumina, solphtir 
J and soda. 

1 Vitri6ed oxide of cobalt, 
I silica, and potass. 

}FerroseBquicyanoret of 
peroxide of iron. 
Ditto and alum. 
1 From the leaves of the 
J indigofera. 
Corbonaleofcopperfclime 
Nativctcarbonale of copper 

}Sabphosphato of iron and 
earthy matter. 



ORAXGE. 

Orange Termilion, orlBisalphuret'of mercury it 

ei tract of. / subsulphute of ditto. 

Chrome orange Bichromate of lead. 

r\ t J 1 Mixtare of proto- and 

^^"^B" *""* I deuto-oxides ot lead. 

Orpiment SuJphuret of ancQio. 

PURPLI8. 1 Compound of the oxidea 

Coasins purple J of gold and tin. 

Madder purple I ^"" *'•*= "»" °^ "»*»*■ 

' *^ J bntorum. 

Carmine purple Carmine partially charred. 

GKKKNS. 

.Sdiecle's green Arsenite of copper. 

Verdigris Sub-ncetate of ditto. 

.,. , 1 Prenaratinn from salnhate 

Mineral green ..... ... > •- ' 

* J of copper. 

Mountain ditto Notivccarbunateof copper 

1 Prom the juict- of buck* 

f Uiorn berriee. 



Sap green 



BROWN. 1 Oxide of manganese of iroD 

Unber J and earthy matter. 

Vandyke brown Peut or bog earth. 

Ivory broim Bones partially charred. 

Asphaltum Mineral resio. 

., 1 Ditto combined with ani- 

MummT r . 

' / mal matter. 

Antwerp brown Asphnltnm. 

Bistre Soot of wood fires. 

o 1 From the fish sepia (cattle 

S-^P'* I fish.) 

Chesnut brown From the horse chcsnut. 

N^trutint }^''^,7"1°LX: ^"- 

nUACK. 

Ivory black Bones charred to blackneit 

Lamp black Soot of restnons wood. 

Frankfort bl«jk } "^""^J^^ **^^"'' '^ "' 

Blue black Chari'oal. 

Spanish black Charcoal from cork. 

Indian ink Lamp black, Stc, 

Black lead Native carburet uf iron. 



DURATION OF MACHINERY. 

The time during which a machine will continoe to 
perform its work efreclually, will de|»end uhirHy 
upon the perfection with which it was originally 
constructed, — upon the care taken to keep it iu 
projwr repair, particularly to correct every shake or 
looseneas in the axe*, — and upon the smaUDCSS of 
the mats and of the velocity of its moving parts. 
Every thine; approaching to a blow, all sudden change 
of direction is injurious. Engines for producing 
power, such as wind-mills, water-mills, and steam- 
engines, nsually last a long time. But machinery 
for producing any commodity in great demand, 
»eldom actually weara out ; new improTCmentj, by 
which the same 0[>eration8 can be executed either 
more quickly or better, generally aupersrdiui; it long 
before Cbat period arrives : indeed, to make such an 
improved machine profitnble, it is usually reckoned 
that in five years it ought to have paid itself, nnd in 
ten to be suprrseded by a better. 

"A cotton manufacturer," says one of the wit- 
nesses before a committee of the House of Commons, 
" who left Manchester seven years ago, would be 
driven out of the market by tlie men who are now 
living in it, provided his knowledge had not kept 
pace with those who have been, during that time, 



S82 



MAGAZINE OF SCIENCE. 



cofuUntly profiting by tlie prof;rcsuve improTemenU 
thai have uXcn plice tn ihac period.'* 

The fSect of iinprovemeiiU<i in itmchinery, seems 
ilicidrntntly to increase production, through a cause 
which may be thus explained. A manufacturer 
milking the usual profit upon Xiia napital, iarcsted 
in looms or other mnchines in perfect condition, the 
market price of making esch uf which is a hundred 
pounds, invents some improTement. But this is of 
such t nature, that It cannot be adspted to his 
present engines. He finds upon csiculution, that 
at the rate at which he r-an dinpose of his manu- 
factored produce, each new engine would repay the 
cost of its making, toj^ctbcr with the ordinary profit 
of capital, in three years : he also concludrjj from his 
ttXperieace of the trade, that the improvement he is 
■bout to make, nill not be genemlty adopted by 
odicr manofactarera before that time. On these 
considers tions, it is clearly his interest to sell his 
present engines, errn at half-price, and construct 
new ones on the improved principle. But the pur- 
chaser who gives only fifty pounds for the old 
engines, has not so large a fixed capital inrcsted 
in his factory, aa tlie person from whom he purchased 
thetn ; and ss he produces the same quantity of the 
manafnctured article, hia profits will be larger- 
Hence, the price of the commodity will fall, uot 
only in consefjufincc of the cheaper production by 
the now mschines, but also by the more profitable 
working of the old, thus purchased at a reduced 
I'rice, This changr, however, can be only transient ; 
for a time will arrive when the oUl machinery, 
•Ubongh in good repair, most become worthless. 
The improvement which took place not long ajco in 
fratttcs for making patent net wai so great, that a 
msehine, in good rrpair, which hnd cost rJUO/.,yoId 
a few years after for 60/. During the groat spe- 
culations in that trade, the improvements succeeded 
each other so rapidly, that machines which had never 
been fiuiilied were abandoned in the bands of thrir 
makers, because new improvements had superseded 
their utility. 

The durability of watches, when well made, is 
very remarkable. One was produced, in going order, 
before « committee of the House of Commons to 
ioquirc into the watch trnde, which was madc^in the 
year t(>60 ; and there are many of ancient date, in 
ttie possession of the Cluck-maker's Company, 
which are still aciuatly kept ffoiaff. The number of 
watches manufactured for home consum])tion was, 
in tlie year 17^8, about 50,000 annually. 

Machines are, in same trades, let out tn hire, nnd 
a certain sum is pud for their use, in the manner of 
rent. This is the case amongst the frajnc-wurk 
knitters : and Mr. Heuson. in speaking of the rate 
of payment for the use of their frames, litates, that 
the proprictnr receives such a rf'nt that, besides 
paying the full interest for his capital, he clears the 
▼alue of hit frame in nine years. M'ben the rapidity 
with wbirJi improvementa succeed each other is 
eousiderrd, this rent docs not appear eiorbitant. 
Some of theie firames have been worked for thirteen 
yean with little or no repair. Hot circumstances 
occaaiotuUly ariee which throw them out of em- 
ployment, either temporarily or permanently. Some 
years since, on article was iotroducedcfiJInt **eut-ujt 
work," by which ihc price of stocking frames was 
greatly d«*teriornted. From the cTideace of Mr. J. 
RawsoD, it appears that, in consequence of this 
change in Ute uHtuie of the work, each frame eould 
do tkt work uj two, and many storking frMmpj were 
thrown out of cmploymenC, and their value reduced. 



e, SBS 

i 



This ioformatjoa is of gnnt importamre, if til* 
numbers acre given are nearly correct, and if nir 
other causes intervened to diminish tJie pries uf 
frames \ for it shows the namcrtLMl cotinc-ijtin ha« 
tween the increased production of those madiiaoi 
and tJieir diminiahed ralue. 

The great importonceof limplif^iogall transactloot 
between moEters and svDrkmen,mud uf dii<paswuiiita{y 
discussing with the Utter the influence of any pn»* 
posed regulations connected with their trade, \% well 
exemphfied by a miBtuke iotu which both partiM 
unintfjuionMliy fell, and which was productivs of 
very great misery in the lace trade. Its history ii 
so well tuld by William Allen, o frame-work k-uitlCTp 
who was a party to it, that on extract from his cvW 
dence, as given before the Frame-work IsLiutttn* 
Committee of 1S12, will best explain it. 

" 1 beg to soy a few words respecting the fraine- 
rent ; the rent paid for Isce-frauies, cmiil the yc»r 
IH35, WAS Iff. Gff. a frame per wrck ; there then was 
not any very great inducement fur persons to buy 
frames and let them out bj the hire, who did vttA 
belong to tlie trade ; at that time an attempt »is 
made, by one or two houses, to reduce the pricia 
paid to the workmen, in conaeqnence of a di^puta 
between these two houses and another great house: 
some little dtfTcrence being puid in the price uspiif 
the respective houses, 1 was one chosen by tltc 
workmen to try if we could not remedy the impnut- 
ing evil : we consulted the respective parties, snA 
found them inflexible ; these two hoosca that 
about to reduce the prices, said that they 
either immediately rednce the price of making 
or they would incresBe the frame-rent : the diffei 
to the workmen was considerable, between the 
and the other ; tbey wonid suffer less, in the in* 
mediate operation of the ihuig, by having the rat 
advanced, than the price of making net reduenl. 
They chose at that time, as tbey thought, the lesws 
evil, but it has turned oat tu be utberwi»; Itrri 
immediately aa the rent was raised upon the pel 
ccntage laid out in frames, it induced almost c^cfy 
periiou, who had got a little money, to lay it out tn 
the purchase of frames; thcae frames were placed 
in the hands of men who could get work for thoft 
at the warebousea ; they were generally coujtLratnail 
to pay an enormous rent, and then they were coib* 
pelted, most likely, to buy of the persons that kt 
them the frames, their butcher's meat, their g io w ty , 
or their clothing : the encumbrance of these frsmn 
became entailed upon them : If any deadnesa tool 
place in the work they must take tt at a very reduoad 
price, for fear of the oonse^nencea that would Cill 
upon them from the person who bought the fcana: 
thus the evil has been daily IncreaMng, till, ia 4^aa» 
junction with the other evils crept into the Cndiw 
thry have almost crashed it to rLouis.** 

The evil of not assigning fairly to each too)| or 
each article produced, its proportionate raMe, w 
even of not having a perfectly distinct, simple, aa4 
definite affretmimt b<;tween a mmter and hie work- 
men, Is Very coniriderable. Workmen fiod it difficult 
in such casrtt to know the probable produce of their 
labor; and both parties arc often Ird to achMt 
orrangemeots, which, had they been well cxamtBta« 
would have been rejected us et^ually at variaaoe il 
the results with the true intercrCs of boUi. 

At^Uirminghoui, stamph and dies, »i>il nrr^Kiu^ 
a great variety of articles, are It' us 

generally made by men possessiug tu ^od 

arc rented by workmen. Power Bl*i> u reui«4 st 
the same place. Steam cogincs are erected in lar{« 



MAGAZINK OF SCIENCE. 



3S3 



eontainlng a variety of rooms, in which 
may Lire one. two, or aoy other amonnt 
power, OA hii occupation msy reqatre. If 
ooald be discoveretl of transmitting; power, 
mueh loss fivm fhrtion, to considerable 
and at the axme time of registering the 
1^ made uae of at any particular point, a con- 
chan^ wuutd probablf take place in many 
of the present system of msnufarttiring. A 
'eentnU en^^nes to produce power, might thea 
in uur ^reat towot, and each workman, 
■ quantity of power sntficient for hix purpose, 
kve it conveyed into his own hoase; and 
rition niiglit in some instances be effected, 
Id be found more pro6tablc, back again from 
ST&lem of great factoriea to that of domestic 
■lannfartnre. 

The iranwTiifision of water through a series of 
lipfs nuj^ht he employed for the distribution of 
hut the friction would consume a considerable 
I. Another method has been employed in 
iostaoces, and is prac^i»^^d ut the Mint. It 
in cxhsasting the air from a large ressel by 
at a steam en^ne. This verael is connected 
with a fimaJl piston which drives each 
and an opening a Tatvc, the pressure 
air forces in the piston. This air 
lltted to the general reservoir, and pumped 
engine. Tbo coudensadon of air might 
tployed fi^r the same purpose ; but it mu«t be 
tCed, thst there are some unexplained facts 
rt to elastic fluids, which require further ob- 
is and eipehment before it can be used for 
[coOTeyancc of power to any considerable distance. 
been found, for instance, in attempting to 
furnace by means of a powerfol water-wheel 
air through a cast-iron pipe of abore a mile 
that scarcely any sensible effect was pro- 
[tiia opposite ejEtremity. In one instance, 
' lenial obstruction being suspected, a cat 
St one rnd found its way oot without injury 
Other, thos proving that the phenomenon did 
id on interruption within the pipe. 
It portable form in which power csn be 
1«, perhaps, by the liquefaction of the 
Ic it knann that, under considerable prcs- 
reral of tfaeae become liquid at ordinary 
irei; carbonic acid, for example, beiog 
to a liquid state by a pressure of sixty 
iheres. One of the advantages attending the 
th«9e fluids, would be thnt the pressure exerted 
^srottld remain constant until the last drop 
had aasnmcd the form of gas. If either of 
its of common air should be found to be 
of redaction to a Uqnid state before it unites 
corrosive fluid with the other ingredient, then 
possess a ready means of conveying power 
> quantity and to any distance. Hydrogen 
tly will require the strongest coropresaing force 
ider It liquid, and may, therefore, possibly be 
where still greater condensation of power 
ited. In all these oases ibi; condensed gases 
i.-iifPfj upon as spriugs of enormous force, 
(•n wound up by the exertion of power, 
il deliver the whole of it back again 
rojuited. Theae springs of nature differ in 
iT>peots from Che steel springs formed by our 
for in the compression of the natural springs 
quantity of latent heat ia forced out, and in 
iro to the state of gas an equal quantity 
Mat not thia vu-ry property be em- 
'vith ad vantage in their applicatioiL 



Part of the mechanical difficulty to be overcome 
in conitmctlng ipparaius eoonectcd with liqnefteil 
gases, will consist in the structure of tlte valves 
and packing necessary to retain the fluids under the 
great pressure to which they must bo submitted. 
The effect of heat on these gases has not yet been 
sufficiently tried, to lead us to any very precise 
notions of the additional power whicb ita appUoatioa 
to them will supply. 

The elasticity of sir is lomelimes employed as s 
spring, instead of steel : in one of the large printing- 
preases in LfOndon, the momentum of a considerable 
mass of matter is destroyed by making it condense 
the air included in a cylinder, by means of a piiton 
against which it impinges. 

The effect of competition In cheapening articlei 
of mannfactare sometimes operatea in rendering 
them less durable. When such srticlos are con- 
veyed tu s distance for consumption, if they are 
broken, it often happens, from the price of liibonr 
being higher where they are used than where they 
were made, that it is more expensive to mend the 
old article, than to purchase a new. Such is usually 
the case, in great citi^, vrith some of the commoner 
locks, with hiogcs, and with a variety of articles of 
hardware. 



LINE ENGRAVING. 
Tns subject having been forwarded by mesiu of 
etching, (as we have already described,) the process 
is completed by engraving. This ia cxccated by an 
instrument called a ffrmer, which is either square 
or lotenge, according to the work for which it is to 
be used. In the operation of cutting the lines with 
a graver, there is a roughness, or burr, thrown up, 
which must be removed by the scraper. Lines in 
sn historical piece or portrait arc oot cut to their 
depth or thickness at once, but are produced by 
being frequently re-entered with the graver. This 
not only gives cleamesa, but also depth of tone, and 
regularity of line. The first cutting of lines with 
the graver is termed laying in the shadows ; all the 
effect being produced by the finishing. To facilitate 
the progreiis of the work, where depth of tone ia 
required, those parts are subjected to the operation 
of rc-biting ; by •which means, in the course of au 
hour to two, an effect may bo given to the work, 
which would have taken some weeks by the more 
tedious use of the graver. To see the slate of the 
engraving without sn impression, sd oil rubber, 
with black in it, is used, with which the lines are 
filled np ; and a pretty good idea of the effect may 
be ascertained. The more delicate parts of an 
engraving ore generally done in tlry jmnt, that is, 
by means of the etching needle pressed into the 
copper, 80 as to produce the depth of line required, 
and the bnrr afterwards scraped off. 
- If the cngrarcr makes a mistake, or changes hii 
mind, respecting any part of his work, (his can be 
remedied by scraping it out, or concealing it by 
barnishiog it firmly ; and, if not too deep, it can be 
polished with charcoal and water, and afterwards 
rendered more smooth witli the burnisher. But if 
the part taken out u strong, it will, in all probabi- 
lity, be below the surface of the plate. In which 
case it must be struck up ,■ by marking the exact 
size and situation of the hollow, on the back of the 
plate, by a pair of callipers, and placing the face of 
the plate, on s finely polished steel anvil, beat it np 
with a bqulU hammer, to the level, from behind. 

In the process of engraving, a shade of tiasne 
psper is u^ed, to prevent the rcrflectiou of 



! 



I 
! 



< 






MAG.vZtNi!/ \jv ^^ 



the cop|>cr intn the t^n. Thit. a maile by puting 
paper on a hollow stretching frame, which U phc«U 
with it^ bote near the till of tlic winrlow, while the 
top part projects oblii|acly into the rooio. This is, 
hnwrrer, quite unoeo^sAary in etching. Ao expe- 
rif-ncMl eye con, at once, detect which lines huvc 
b«en etched, aiid which have been produced by the 
grsvor. The former ere always more or leas aer- 
rated on their edgca, while the latter are clear and 
smooth. Mofft enf^ravera tue a glasa, both in etching 
and finiahini; Uieir idates. 

Engraving in Outline. — ^This method is well 
adapted for (he re|imeiitation of getuK and ttaluary. 
where a likeneaa of an object i;^ to be given, and 
where it is desirable to avoid the expeo8« of a 
finiahed engraving. &.s a iiab«titute for ahadows. a 
stronger line ia cat, which also lakes off from tlic 
tamrness of a uniformly thick line. Outline may 
either be exccnted by first etching the subject, and 
cutting the atrontjcr lines with the graver; or it 
mny be done by trauaferring the subject to the cop- 
per by ronina of a wax ground, and the oatltue 
■cntched mth the point, as in wriling, and then 
cut with the graver. 

Stippling. — This is engra^g in dots in place of 
lines. There are two wayn of executing thiaspecies 
of engraving.. The first is by pursuing the same 
process as in an etching, ond having the subject 
transferred to the jilnte. The outline and part of 
thfl shading is executed with an etching point, and 
theo bit, as deicnbed in etching. When the ground 
is removed, tlie engraving ia completed with the 
grarer. The dots produced by the point are ne- 
cessarily round, while those made by the graver are 
somewhat rhombuidnl, or slightly triangular, de- 
pending on (he kind of graver which is used. If 
engravings of this kind are examined by means of 
a lens, it will be found that what appears a single 
dot to the naked eye, consists of a number of very 
minute dots. This gives to the engraving that 
beautiful softness which is observable in the works 
of RyUnd, Freeman, and oUier first-rate stipple 
engrsvera. This kind of engraving ia more tedious 
in its execution than line engraving, and heaoemore 
expensive. Stippling has much softness and re- 
sembles a drawing ; indeed, when printed in colors* 
engravings of this kind very closely resemble 
colored drawings. 

In the coarser kinds of work, an instrummit has 
been deviaed for producing dots in a more expedi- 
tious manner than by the point or graver. This is 
called a rowfe/fe, a kind of toothed wheel, resembling 
a spur, moving on a pivot, but with ^om three to 
six or eight rows of points ; bo that by running this 
along the face of the plate, a large surface or shadow 
can be produced in a very short lime. Thia is, 
however, quite inapplicable to the finer kinds of 
work, ai the mechanical reguhirily of the dots cannot 
be eoncealcd without much labour. 

ELECTRO-GILDING. 

{Tu ikr FAUor.) 

8im, — Seeing amongst your Answers to Corres- 
pondeuta in your last Part, that yon seemed to 
have failed in the electro -gilding, I have sent yoa 
tbeae few lines, which, if you think them worthy 
yniir pages, yon would perhaps insert. 

Tite manner in which I succeeded was this, viz :^ 
1 took \ii ^.Ib. pots of Mr. Grovels battery, in not 
rery great activiti/, placed the anro-cyuiiide of 
pvtaasium, (which*! obtained from Dymond's, High 



Hnlhom,) in a glass or earthcnwars vesarl, ~ 
artide to be gill inmerted In it, coanooted > 
xincode ; to Ibe wire from the plaUnodc 1 v( 
a piece of platinum wire, at Jinc an a fiair, 
immerse it (he smallest possible de^rr ■ • ■' ■ •'-• 
solution, just above the surface of the 
gilt, and the gold will be beautifully i; 
in its metallic state. The gold thrown duwn 
much paler than the gold produced by Ui 
gilding. It is very essential that the surfscr 
article to be giJt is chemically clejui ; waalj 
article in boiUng snlpbnric acid is generally eun^oieiiL 
The salt spoon inclosed has been gitl by Ihestniv* 
process about a year and a half, and has been 
con&tant use ever since. The silver palate plates 
deultsts whidi 1 have gilt in this way have st 
very well, the silver not being acted n|}on by tiiS 
saliva, u in the plates done by the water gilding. 

JOHS BOCaSTT. 
I, Errrrtt Stnmi, JtuMiitt SfUdrr. 

I ahould think any other galranic battery would 
anawcr as well as Grave's, but as to tlat one I 
speak from proof. 

[The salt spoon alluded to, and wtdfih wt bivt 
tent back by post, shows that the abovr ia attmdcd 
with great suc-ceaa. — an.] 

MEMORANDA. 

Tlie great difficulty in improving teioaeopea hu 
been the manufactnre of flint. ^1^ 
cicnt aixe. Fraunhofer made ct 
irurbm diameter, and 14 Ivr '-^ 
niftes from \7h to 700 tin. 
has one of 12 inches dirm 
length, in his obiervatory at Krminglon. To 
viate this difficalty, Mr. Barlow Ua* made nn 
strument with a plate-^Uss object-gtu- 
rected tbe colors, by luterposing a !■ 
Bulpburct of carbon, whose refraction is ri>nr oi 
glaas, while it h |>erfeclly transparent. The 
lens, of conrse, r-nlarges the anglf. Jtul Itn-rtJ 
the magnifying power. A 7'nrt int inHlmmrat, 
therefore,magaifiea 700 tunes, buf « i '^ Ui^^li-hr tTr«n 
Sir James South. Rogers has i 
pose flint-glass of smtiller stse. 
h&s a reflector of 20-feet, with « 1 
that no other telescope in Euro].- 

DoUund*a discovery of the n 
crown-glass and flint>glaaa vras i: 
the reaiilt of a long acriea of t , 
with a view to sustain Newton's errui 
refrangibility and dispersion, which !>> 
puted by Euler. It was an English maitntM(urff 
till the French began also to moke flint-glai 

As the sixe of every object is the oei 
diamel(^:r subtends, so the tme pnwi 
scope is the increase of that line ; bui 
the wonder, many sijuore the line for th- i 
and othera cube it for the solid. Thi 
20 is often called 400 or UO(m. 

A plano-convex lens has the greatest field of rtrv; 
double and equal convex the least ; the aids of least 
convexity should be nearest. 

The Mund of a bell dies away as the ezhaasttot 
by an air-pump proceeds; but sound rnntinaal, 
since the exhaustion cannot be |M!rfect. 

A bell not only does not sound in an fthailM 
receiver, but if in s receiver not rih(.u$Trd ai 
covered by another, and the in' 
hausted, that void space will not 



i'^ 



LosiioM.~Pnot«d by D. Vbuoib. S, Wiiite Hnn« Lds. Hila Kod-— PubII>bo<1 by W, B«iTT*ni. 1) 
CvmsiunirsUons. iwhich arc omwetrd Monthly,) to bv addrtsieii l« 11m fUilor.at K. Cultage Orv< 



THE 



AGAZINE OF SCIENCE 

^nm ^ttool of ^m. 
153.1 " 




^^—GOOCH'S MACHINE FOR ASTRONOMICAL ILLUSTRATIONS, 

Hlfflt. — NO, XLIX, 



3S6 



MAGAZINE or SCIENCE. 



GOOCH'S MACHINE FOR ASTRONOMICAL 
ILLUSTRATIONS. 

fTv //« Edilor J 
Sm. — Obierring in page 297. vol. I, ft hcautifa! 
diipUy of fireworki, unonf^st which, tlie art o( 
tun-makiny, I tmke the liberty to ahoff you my plao 
of «im and nimm making. I luve now by me a 
roichina or frame which fiti into ■ boi, where U^bCs 
«re containcil, which beautifully rrpresenta the tun 
in foU BpleDdor, together with the earth ud moon 
revoWini; roand the centre of gravity. 

C C C C, i« the frame which contAius the appa> 
ntu with a hole or apertiim cat out : and at the back 
of tbii aperture is plnced i inoreable plato of paste- 
board or rard.paper AAA; in it are cut the foar 
holea for llie moon M M M, and also the circle that 
npreaeiits the earth ■ over theie holes is stretdied 
some fine silk, or transparent pAper. The whole of 
thii tama freely on the pin or centre uf grkvity G, 
and to which pin is also placed a pully, to pat the 
same in motion by other coaoectcd pollitis. Fixed in 
the frame B B 11, is a xinc or tin pUle fixed to the 
bank of tlie frame, in the form qr represented In the 
dmwiDg; so as to hide the light of the moun to 
form Uie difTereut phases, as she raovn roand the 
centre of gravity ; cousequmtly, tu (pvc the sppesr- 
anoe of fall moon, new moou, and all the other 
phsaes. as she rcvolvea according to her situation to 
the sun with the earth. I have tlBO placed dko ton, 
as yoD see, in the same frame. It i» constnict«d 
thus: — K and K L. are tin cylinders, made to fit on 
each otlier, and move freely, by tlie connected ma- 
chinery. pulUes or wheel-work. At the buck of aach 
cylinder, as at D and G, is a lamp placed, sad the 
front of the aperture of E is coTered with aflk or 
paper; the front of these cylinders is made flf 
xinc, P and H are flODcave; D is the outeraioit, 
both are perforated^ one with slits and the other 
with botes, in opponte oblique directions, BO that 
when the machine is put in motion, it has a beautiful 
appearance like the sun's rays diverging from the 
outer portion of the disk in oblique rays, or tan- 
gen ts. 

Fig. 2, is the slide holder, and which maybe ued 
with any apparatus of this description, either for 
entertaining purposes or for astrunumical illuftra- 
tioos. A A A is nn iron frame, and in which the 
frames or views ore to be placed ; at A A are naall 
projecting (4eces which fit into a groove in the 
picture frame, and are fastened by two screws C C, 
to Itold it steady. B B, is a brass upright rod, on 
which C C slide and carry the frame, which is kept 
steady by a spring D ; this will be found eicced- 
ingly convenient to eihibit the differeut views. 

MwmelL B. COOCH. 

BLACK-LEAD-PENCIL DRAWINGS. 

Taaat drawings have their admirers ; they can be 
finished up to considerable neatneiui, or to powerful 
effect ; and therefore s few hiuta rr«pcrUng such use 
of the lead pencil are lubjoined. The pencil should 
be of the best Cumberland lead, and it should not 
be cut to a point, after the first lime, until the ez- 
hsQttion of tho lead renders it absolutely necessary. 
The blunted pencil, by being waped upon a form, is 
capable of giving to it any degree of sbodB. The 
term waved is not explanatory : the process is. 
pasaing the pencil backwards and forwards in zig- 
s^9 of convenient length, in such manner as not 
$Q repeat oae mukio^ oa uiotheri but m c\qw u \a 




produoQ an eqoality of tone over the space repaired. 
This unifortn tone is called thr ffrain , and by ju- 
dicious waving, in different directions, any gradation 
of strength may be oommuni<rsted. The point of 
the pencil is destructive to the e^ect alluded to. be- 
cause it will give o line which repetitions on!; reader 
more offensive. 

The clearness of this grain produced on mtmm 
which have been previously drawn with a taoder ool* 
line, is essential to the prcserrstion of distances hf 
gradations of power. It is the perfection of thh 
kind of drawing, to efTect as much as poasible inde- 
pendently of outline, or the evidence of it in Iht 
process of wa?ing in the masses. Tbos, the most 
remote parts may be waved in, as if there wert ss 
little light on tliecn that they would be indtitioAlf 
seen — tiie second pJ^n waved in as if a grtmitx de- 
gree of light, or raCier distinctness, wrrr cast opot 
it, the objects being n»>rt ddlned and proportionally 
Btnmger tfasr. the ditUnce— the CBncroand ^tnd' 
with tlie greatest degree of light coat •■ lt» 
render every part evident, by power and 
tonoh. 

In examining a natural scene, it may hi obscrtal 
that all is void of outline, and that svvrr distiovi 
object is relieved from ihnt which a4iouu it. by a 
separation of light, shade^ or other accidental prcs- 
liarity. In sketching, neverthdeas,oatline isadopud, 
becanse it is Xim only meana of obtaining a knowledgo 
of the forms, aud the simplest dmsm of dftofhiH 
them : but immediately oftor the stadsnt ahdl ba«t 
become acquainted with the form of an object, it mmt 
be considered as having been operated upon by light, 
aiid the portion of outline which is neat the 
of illuminstinn, should be more liilidBi|| 
tlisn those parts which may be dilferentiy 
Now, this attention tu light and shade in ovUiac li 
preparatory to the more correct reprossatatioa ti 
nature, and the student oi^t to be sstisfied, ihsL 
in whatever may be attemfrted, time will not be lost 
in the endeavour to pi wi ivc the proper tights sad 
shades. At first, those undertakings should foe of 
the simplest kind ; thero la no production of boun- 
tiful nature that is not worthy of consideretkni, or 
that is incapable of yielding its rsword lothe atten- 
tive student. Suppose it to be the leaf of a wiUnw. 
the elongated curve, with its smooth edgw, and ta- 
pering vein down the centre, offer practice for eom- 
maad of hand in conveying the imitative Udses to the 
paper, whfle a perfect knowledge of the dmracta of 
the leaf is st the same time acquired. It Is impos- 
sible thus to opi>eal to original nature, withont ob- 
taining valuable information. 

Thr leaf of the elm, with its contracted cnrrc, 
serrated edges, and many veins, offers aobjccta for 
practice nod closer inspection of form. T)te oak, 
with its longer leaf and waving edges, prrseot* In 
the investigating mind a great variety of form and 
character ; but tlieoe teavea present tbemsrlvcs in 
many peculiar forms, that give an increased interest 
to the lines tliat may describe them. They src lo be 
seen curved in a picturesque manner, twisted in fisn- 
tostic shapeo, and clustered beautifully. Let the 
sludent select from any tree a small sprig, having 
three or four leaver, and place it naturally in fruat 
of the drawing board, as an object for study. Thai 
attentively examine the position of each leaf, fta 
graceful connection with tiie Ktem, and the inscftisn 
of the Icaf-atalk into the wood. Such a trmnqad 
investigation uf the distinct parts of which the nb* 
ject ia compoft'rd, has been obaerred to leMra acon- 
lukiAik qC ideat that Uhes pOMcnhw of s jvrnulfl 



MAGAZINE OF SCIENCE. 



387 



■ni^cnt, wbea as t whole it hts boen contemplftted, 

- ' T ((laDced at, witli a fear of notb«in|^ able to 

':< Kit WM if-en . Why fear * wliydelaj^? baa 

Ktd. Not knowing wbore to begin, or not 

■ 5 hi>w to aeparate the part«, has been the 

This was not deficiency in power of mind. 

bat a Mcming rrluctaQce to call it forth. Nothing 

f»n h^ done while the eye in roving over the object ; 

nning, no end appcan. Let the mind be 

to act upon what is required ; direct the 

iiirnrion to that part which may be deemed the 

prinnpAl, or the moit con&picuoui lejif upon the 

•prig : coiuider tU poaition ; observe if it project to 

(be front, or laterally; what portion of the upper 

««iface ia seen ; and if bo, bow it in eorled to dis- 

pUy any part of the aoder aurface. When all that 

r^lea (o the principal leaf has been thought npoa^ 

the part on which to commence is auggeated to the 

mind, and the hand imitates that to which the eye 

b •tsdlously directed. 

The Brat leaf being lightly aketcbed, it is easy to 
aU «a adjoining leaf, and so on till all be on the 
jHper. The student should then coolly criticise hia 
#orlc, lookiog over otery part, to detect any doriation 
frofla fbfl forms of the original, if this examination 
■ad correction produce likeness, let the lines and 
ehumeteristie marks be drawn in with a firmer or 
koMer pencil ; very often the most trifling touch in 
•Mition will communicale what seemed to be re- 
quirrd to gire character to a leaf. A weaker line on 
tAt aide which meets the light, and the stronger line 
Mttfined to those parts which may be opposed to the 
light, materially assist in giving satisfaction, from 
the spirit which such sketching impsrti. The stu- 
tfeaC ta at all times advised to be spnring in the use 
«f Indian rubber ; at times it is useful, but generally 
It is brought into action, because thought had not 
prmi>aaly been suflicicuUy employed. 




The above figure may serve to couvey an idea of 
wbat is intended by the preceding remarks. The 
light is from the right, on which the tenderest lines 
arc prtserved, while those opposed to the light re* 
ceire a more' powerful marking, with occasional 
locreaK oF force. Such studies as tiieae should be 
made in the fields, whero there is not a hedge-row 
but presents numberless subjects, each with its form 
and characteristic touch — thr. plantain, the dock, aod 
the thistle ; the fi^rn, the briar, and the chom. The 
advantages to be derived from consulting these ob- 
jects inhere they grow, must be obvious to every one 
who will admit that originals are superior to copies, 
which all prints and drawings are. The student 
fSftO as easily copy from nature u from an imitation 
of nature ; in the one instance the sketches are 
SQch a* were diclnted by love of the art, and so far 
are originals ; b the other case, however closely 
the cketc:he» may have been imitnted, they are mere 
KTvUe copies of what anotticr thought to be rcpre- 



sentatioiu of nitars. The only method by which to 
produce a satiifactiou that stimulstea to e;tertjon in 
drawing, is to itudy and copy carcfolly the chanKV 
trristic forms of objects aa nature presents tliem* 
Let the student be provided with two aketoh- books, 
one for scenery, and the other for smaller studies, 
called *' Mt." That which is shut may serve as 
a seat for the draughtsman, while be has his pencil 
at work upon the other. In sketching a plant, 
first observe if the outline be smootli or rough; 
bow the leaves project, recede, point vertically, or 
recline on each other. Endeavour to arrive at • 
oomprehentive notion of the vrark llut is to be done, 
including a perception of what is very appropriately 
called the feeling of the subject. Then commence 
by sketching th« form of the principal or moat coo- 
spicttoua leaf vrith a tender line, and correct it, if 
required, without rubbing oat, until the general 
form of the leaf shall appear amid the lightly 
sketched lines ; this the mind will seise upon, in 
consequence of tlie likeness being perceived ; tlien 
let this line be put in with a little more power, and 
with s handkerchief brush swsy the first trials. The 
leading feature of the plant being thus laid down, 
the rest, which arc ne^xssarilj of the same character, 
will be easily executed, care being taken to observe 
from what part a secoud leaf may issae. Be atten- 
tive to the commencing line of each leaf, snd proceed 
as with the tirst, tilt the whole group be sketched in. 
Do not nejjlect any part, nor conclude that enough 
has been sketched of a subject so simple, uor think 
that at another time it may be more carefully at- 
tended to ; these are the causes of fsilore ; no time 
ia like the present ; eudeavoor to obtain a correct 
outline, at the risk of being considered very alow. 
I^t the object be well sketched, and rapidity will 
foon be acquired. When the character ahidl have 
been fixed, the detail will go amoothly on; the 
knowledge of the plant, with its peculiarities of 
growth, and iUi natural appearance, will never depart 
from the memory. With reapect to indications of 
light and shade and touch, the soft pencil may be 
pressed with power on the shade-edge of the leaves, 
with occasinrul repetitions, or the thickness of touch 
may be doubled, to indicate curves, or the curled 
edges of leaves. At all times give a boldness of line 
with a peaeil rather soft, becanse it can be used with 
more freedom, and will commuuicabe more spirit, 
than a hard or fine-pointed pencil. The lines of 
which a sketch may be composed, will appear fine 
ur cuarse, more by a comparison between the strength 
of the lines on its light and on its shade lines, or 
touch, than by reference to ordinary thinness or 
delicacy of line. This is mentioned to induce a 
boldness of outline in whstever may be attempted 
from nature, since it admits of freedom in eAccution, 
and expression of character which con be recognised, 
while tlio clforts with a fine-pointed pencil produce 
a meagre aud spiritless effect. 




Tlte figure annexed is a combination of rural 
objects that oaaj (cc^v^taU^ \» ^^wtntA wa. Niw. 



MAGAZINE OF SCIENCE. 



DOW benetth the piston, &ad U la forced apmrda ; 
wkOe the ateun In tb« upper part of the cylinder 
esc«pe» roto the chimney, nnd thus alternatelj. The 
Bleam, after it leares the cylinder, i« condacted 
through the pipe O, ioto the clumner. This pipe 
ia inclowd in another, containinf the water which 
ia to aupply the boiler by a amaU force pump ; and 
from pasainc; along thia pipe It ia injected into the 
boiler at a hifth tempersture, which saves to mach 
of tlie heat that would otherwise escape into the 
atmosphere and be loat. The rectproeating motion 
may b« oonverted into a rotatorr one by a crank, 
and the motion equaliied by the intenaMlMte me- 
chaisisni of a fly. 

CTo be contimaeiLj 

THE APOLLOWCON. 

Tun mosical machine, which is constmcted on the 
principle of the organ, by a peculiar modification of 
the pipca, producca an nccellent Imitation of the 
tones of all the most admired wind inatramenta ; 
Ihe combined efiect of the whole being mmilar to 
that of a numerOQS and well-cbo«en orchestra. This 
magnificeDt contrivance, anrivalled in this or any 
other country, is the inrcntion of Messrs. Flight 
and Rohson, who spent five years in its completion; 
and as a popular description of it cannot ful to be 
acceptable to the amateurs both of miuical and 
mechanical science, we propose to give such an 
account of the instrammt as may serrc to convey a 
general idea of its construction. In the apoUonicon, 
as in the organ, the sound is produced by a current 
of air. urged by bellows, through several aeries of 
rerticnl pipes. In tfae apoHonicon there are two 
pairs of beUows,lpUced below the floor of the apart- 
meoC in which the Instrument stands; the wind 
from which passes thruugh a reeervotr and a tube, 
called a wind trunk, into an air-tight compartment, 
called a wind cheat. The pipes which, by Toriooa 
modificatioDS of thdr construction, prodacr the 
•ounda of the diflcrent instruments, are ranged in 
rows one behind the other, parallel to the front of 
the machine, in the order of tlie gamut, each note 
and half note h&ving its separate pipe, and each 
parallel row representing a different instrument ; 
the pipes producing the same note in every instru- 
ment lying in a straight line from front to bock of 
the instrument, or parallel to its sides. TIius the 

Eipee prodociog the note A on the Ante, clarionet, 
aatoon, &e., all lie in a parallel to the ^dcs of the 
Inatmment. From the upper part of the wind chest 
proceeds a horizontal platform, termed the bottom 
board, having a aeries of channels cut in ita upper 
surface, corresponding to each note of the different 
•calei, and extending longitadinolly from front to 
rear of the machine. Above the bottom board, and 
at right angles to the channels, are a series of 
groores, corresponding to the transrerso ranges of 
pipea, or the number of the dilferent inatrumenta 
in each groove, are three slides, placed one over the 
other, md throvgfa all three are narrow passages, 
opening into each of the wind channels in the 
botttim board. Over the alides is placed the tnp 
board, into which the pipes are inserted, communi- 
cating with the wind channels through the apertures 
in the slides. The use of these slides is to cut off 
oocaaionaily the communication of any particular 
instmment with the wind chest, so as to cause that 
inKtramcnt to ceaae playing, which is efl'ectcd aa 
follows : — the apaee between each aperture in the 
slides is somewhat greater than the width of the 



lA 



wind channels, so u to eover the channels oam- 
pletrly, and thereby cutting off* the eofninuiiicitiaa 
with the inrtmrnent to which the sltde hclonga. 
Only one slide in each set of alidea it in op«iili«i 
at one time ; the a{>ertures in th* oCfaor two hII 
being over tlie wind channels, and hdow the epar- 
tares of the tnstnunenta. One set of elides bin^ 
oaed when the instmment u played by the ■•- 
chanical action of the machine, another set Is moi«d 
by |>edala, and the third set by hand, when It b 
played by the keys. At that end of each wind groote 
(hat opens into the wind cheat, are two haogiof 
valves, called pallets, which admit the air into, a 
exclude it from, the wind grooves; and the art of 
performing upon the machine coniiats in the mftoage- 
ment of the pallets and stops before deacribed ; ths 
air or tune being produced by the pallet*, and the 
stops regulating the instruments, vpon which tkt 
air is played. The madiine may be played in twi 
ways, either by performers aeated at rmngea of kry^ 
as in other organ!i, or by mechanical means ; wL 
as this latter method is the distuagniahing cbanoM 
of the machine, and has called forth to mtaoh Ir« 
genoity in its exeoation, we aball deteribe b 
The principle ia as follow* -. — (o one set of the 
is attached a aeries of wires (one to eaeh 
passing through holea in a brass plate in the 
of the wind chest, which are jnat sufficiently 
to allow the wires to move easily, without 
the air to eicape from the wind dicft. These wlra 
(60 in number, bedng one to each note of the sedl 
of the machine.) are connected to one end of a stria 
of small steel levers, set in a frame below the wloi 
efaest, the outer end of tbe levers resting upon tba 
surface of a cylinder somewhat longer than the key- 
frame ; a number of amall pins and bent wim n 
brackets project a short distance beyond the eir 
cumferenee of the cylinder, ranged in lirtea aenM 
the axis, and by the revolution of the cylinder, 
or more of these pint or brackets are brougjil li 
contact with the outer end of the keys, whi^ vi 
thus raised, whilst the other end of the k^a, ani 
the pallets corresponding, are proportionably d» 
pressed ; the wind peases from the wind cheat iett 
the wind passages. The length of time the paUiM 
continue open ia regulated by the length at 
bracketa; and when, by the revolution of 
linder, tbe brackets oome dear of the keya>thc 
end of the key falls upon the cylinder, tbe 
closed by a spiral spring, and the eosunu 
with the wiod grooves is cut off. 

There are tltree cylinders, each 2 feet in 
and each having a separate wind cheat nod key 
frame placed over it, fomishing wind to particiidBr 
portions of tbe scale. The main cylinder 
tbe centre of the front of the machine ; it ia If 
long, and comprises a range uf five octaves : fia^ 
from G G, an octave below first G iu the bast ddf 
op to 6, and eighth above G in the treble clef. In 
a line with this, and concentric with it, is finut^O' 
cylinder, 'S ft. 9 in. for the hasa notes cxtendit^ 
from G G G, or an octave below the former, vp to 
gamut G, being two octaves. The thknl 
lies at the back of the machine, parvUd to the 
cylinder ; it is 8 feet long, and comprises two t^ 
taves. JBelow the two front cylinders attend I 
shaft, or txis, having two pinioita, wbu^h work hi 
two wheels, one on the end of each ryhndcr, sad a 
similar shaft lies below tbe third ryUnder, in i!h 
rear of tho machine ; and beneath these sitafta, atd 
at right angles to them, is annthtrr shaft, 
from the front to tbe back of the machine 



MAGAZINE OF SCIENCE. 



301 



it tfro endleM icrewf, working in vonn-wbeelt 
the twu aliaftN : tliit Ust ahnft receive* iti motion 
by ft band from the dririn^-ihaft. (which hu ■ fly- 
Wboel, and is turned by msnnal Iskor), and caasea 
He cylinders to revolve. The liey-fr«me 14 made 
fin dtttinet pieces, to nltow for the une^jual ron. 
Inctioa of the wood. «od any ineqaalitiet which 
taiaj exift in the cylinder ; and to take the weight 
•ff the key, it ii supported on the cylinder by uli- 
hiction rollers. It remaina now to explain the 
conoexlon of the finger-keys with the palleta. The 
luy-boArds are five in number, Uie central larf:e«C 
,...^ .,,,2^ I gcale of five octaves, aud the smallcr 
flod two on each aide of the larger, theae 
<.;«acale of tiiree octarea. These keyboards 
ad ta front of the inatrument, and detached from 
«o tliat the performen sit with their backa to the 
iMtromcut, and their faces to the aadience. Fron 
fore end of the ftiix*^ keys descend wirea to the 
Ibra end of a aeries of leTers below Cho floor, and 
Is the other end of these levers are alLacbed wirei, 
Vkifib pass through holea in the wind chest, onJ are 
ed to their set of pallets, and thus the de- 
oa of the finger keys draws down the hinder 
sEads of the lower levem, and opens the pallets. 
Within reach of the performers at the keys, are a 
■umber of levera fur moving by hand the draw-stopa 
«a an termed the slides which throw off or on any 
panioaUr instniroeDt ; bat, in addition to these, are 
• atC of (>edsls five ia number, which move a set of 
ps, called compound pedal stops. These are the 
n of Mr. Robbon, and are for the purpose 
•Ottbling the performer suddenly to throw oa or 
M number of instruments by a single moTcment, 
I tikoreby add greatly tn the brilliancy of efloct. 
i The whole number of the keys acted upon by the 
ndcfB is about 26U. 1'here are vpwards of 
1900 pipes, 4^ drawstops, and 2 kettle-drums. To 
Uu musical amateur the following list of the stops 
viU doubtless prove int«re8ting. 
Oa the first cylinder, — 

i, open OiBpuon. 4 Ptioclpal. T. Flnla. 

Otilo d\Ui/. 5. 1 wciinb. 8. S«v)ui Altrn. 
Slop diUO. 6. Ftnf*iith 9. Ci>ruet— Trumpet. 

the second cylinder are two octaves of wooden 
, of large diaienaiona, termed double diapaaon 
ndol pipes: the largest Is 24 feet long, and 23 
nohai square ; this is B foet longer than the cor- 
anding pipe in the great organ at Haarlem. 
Ttnge of the scale is from G G G to G. 
Ob the third cylinder are the following stops,— 

(Uicni Slop. Trumpet. Ilntitbnyii. 

Crrmonu. PlrcoUuL 

, Klutn. Trumpeto. 

iilB. Vvi humaaa. Ulupaaoii. 

cnlh. tfclAve Plate. Prtiuripal, lie. 

haniam ia inclosed in a cue. 20 feet 
d by IB feet deep, uid 24 feet high. l*hefruut 
il divided into three compartments by pilasters of 
Orecian Doric, aormounted by others of the Ionic 
Order. Between the upper pilasters are three 
|«Utinga ; that in the centre repreaenting ApoUo, 
and tboie on the aides the Muaes. Clio and £r«Lo, 
■'»'""«''^t larger than life, which do mnch credit to 
. (Mr. John Wright) by whom they were 
The meohaoical action of the apollonicon 
was hrst exhibited to the public in June, IH17, 
vben the overtares to Anacreon and to the Clemenu 
di Tito, were performed by the cyliniiers in a style 
th«t called forth the roost marked approbation from 
targe and scientific audiences. From tliat period to 
the present lime it has maintained its weli-deservod 
pO|iaUtrity, and continues aa object of iaterest alike 



to ihe musician and the mechonUt, offering to the 
former some of the grsndest combinationa of bar- 
mony, and to the Latter some of the most curiona 
and complicated specimens of hia art. 

FULMINATING COMPOUNDS. 
Tnx most remarkable instances of expanrion by 
heat with which we are acquainted, are those where 
eiploaive mixtures are naed, and where rererbera- 
ttoD of the air ia the coitseqnenee. In the explosion 
of these oompoonds (which are of various kinds), 
the simple nibstaaces of which they are composed 
are either resolved into their primary states, or they 
immediately enter into combination with other sub- 
stances, which, like thcmsclvea, hsvc just beca 
liberated. In most cases, they not only assume but 
retain the elastic form. The uploaion of these 
bodies ia doubtless owing to their combination with 
heat ; but whether the heat haa been hteni in them- 
selves, or whether they are capacitated by a alight 
elevation of temperature, suddenly to rob the sur- 
rounding atmosphere of its heat, is not known. 

If 1 ounce of oil of turpentine be poured into a 
gallipot (pUced in the open air), and 1 oanoe of 
nitric acid, with 20 dropa of sulphuric add, into a 
phial tied to the end of the walking-stick ; the acid 
on being thrown U)»on the oil (at arm's length, to 
prevent accident) will cause deflagration : — abund> 
ance of light and heat being evolved. 

Cover up some small pieces of charcoal Id a 
crucible, and give them a red heat. When perfectly 
hot, uncover the cmeible, and pour some sulphuric 
acid upon them from a phial tied to the end of a 
stick ; immediate deflagration will take place from 
the rapid decomposition of the acid, part of which 
will be thrown out, by the qoiok diaengagement of 
carbonic acid gas. When the action hu subsided, 
sulphur will be found precipitated on the cduucoal. 
Here the charcoal, in the red-hot state, has moitt 
affinity for oxygen, than sulphur hna in the state of 
sulphuric acid ; the consequences are, the formation 
of carbonic acid and the precipitation of srdphur. 

Melt some antimony in a crucible, and when at a 
white beat, |)our some water into a small retort, and 
hold it over a lamp. When the steam pa»es out, 
hold it over the crucible containing the antimony, 
so that the steam may enter into or paaa over it. 
At this Instant, let an assistant agitate the crucible 
by a pair of tongs; a series of very violent ex- 
plosions will take place, as the water, tn the form 
of steam, is decomposed. Here the oxygen com- 
bines with the metal, and the hydrogen ia set. free. 

Mix together I dram of aulphnr, 3 drams of 
nitrate of potass, and 2 drams of carbonate of 
potass, (all previously pulverised] in a aheet of 
writing-paper. When properiy mixed, put thm 
into a small stoppered phisl. An eighth, or s six- 
teenth part of this, pot on a fire-shovel, or tin plate, 
held over the Are for a few minutes, will explode ; 
immediately before the explosion, a violet- colored 
flame will be aoeo to hover round it. 

Reduce aeparately to fine powder, 4 oances of 
nitrate of potasa, 2 ounces of the sulphuret of an- 
timony, and 1 ounce of sulphur ; mix them well oa 
a sheet of paper with s wooden or ivory B|mtula. 
and preserve the compound in a dry phial. When 
it is to be uaed, lay aboat a dram, or more, on a 
pieoe of wood or iron, and fire it with a red-hot 
iron wire ; inatont deflagration, accompanied by 
daxsling tight and great heat, will take place. 

Reduce to powder 10 grains of nitrate of silver, 
and then mix with it 1 gruu of lulphur ; wrap thfl 



MAGAZINE OF SCIENCK. 



cnuture in a nnall bit of ptper. aiid ploce It upon 
an ui?il; mtke b hammer which has a broad sur- 
face pretty hot, and strike the misture with it ; a 
violent cTplofion will take place, and upon exatni- 
nation, the silver will be found in a reduced or me- 
tallic itate. If the banimer be cold, the aulpliur 
only will be afTected ; it will then inflame without 
detonation. 

If 10 grains of charcoal, in powder, be mixed 
with 10 graina of nitrate of silver, also in powder, 
and laid on an anvil, wrapped up iu paper, an ex- 
plosion wiU take place when they are tmkrtly atmck 
by a hot hammer. 

If 6 grains of the nitrate of aHver are powdered 
and miied with 2 grains of phoaphorua in a piece 
of writing paper, then put upon an anvil and itruck 
with a hammer, a very vtoltiit explosion will take 
place. Nitrogen and phuaphoric acid will be dia- 
eofaged. 

Place a crystal of nitrate of ammonia on a ahovel, 
and bold it over tlu; fire; when it has arrived at a 
heat Bufficirnt for melting lead, it will, in the act of 
decompoiition, explode with considerable violence. 

Place 12 gruna of nitrate of copper, io powder, 
mixed with 2 grains of phuepborus, upon an anvil, 
and strike them with a hot hammer ; detonation 
will be the consequence. The aalt will be decom- 
posed, giving out nitrogen gas. Phosphoric acid 
gaa also will be formed, from the union of the 
phof phonu with the oxygen of tbe nitrate. 

If a pestle and mortar are for some time kept 
warm before the fire, and a ready. formed mixture 
of 12 graina of sulphur and 12 grains of nitrate of 
lead, b« thrown in, and smartly triturated, eiplo- 
sioni will tak<^ place. The lead will reaume its me- 
tallic state, whilst nitrogen and sulphurous acid gas 
will be evolved. 

]f 4 grains of nitrate of mercury arc reduced to 
powder, and combined with 2 grains of pbosphonia. 
a roost violent explosion will take place, when they 
are struck amartly by a hot lummcr on an anvil. 
Globules of reduced mercury will be found, upon 
examination of the paper which contained this 
mixture. Nitrogen gaa and phosphoric acid will be 
disengaged ; for the oxygen of the salt cuiubining 
with tbe pboaphonu, forms phosphoric acid, which 
flies off; the nitrogen being thus left free, absorbs 
caloric, and becomes elastic also, whilst the metal 
recovers Ita properties. 

Triturate in a mortar, 2 grsaoa of pbosphoms 
with i grains of nitrate of bismuth ; during this 
operation, violent detonations will take place. 

R«ducr fifparately to powder, 1 ounce of alum 
and 1 ounce of raw sugar. Melt them in an iron 
ladle over a clear fire, stirring the mixture until it 
becomes dry. Hedoce the compound to [»owdcr in 
a mortar when cold. Now pour the powder into a 
strong 4 ounce phial, into which lute a tobacco- 
pipe, preserving the bore of the pipe free from 
particles qf the lute ; imbed the phial in a coat of 
clay, and immerte it thus in a crucible, tilling up 
tbe apace between it and the sides with ssnd. Place 
the phial with its contents in a good (ire. Carbu- 
retted hydrogen gas will escape from tbe upper end 
of the tube, and when this ceases, stop it up with a 
piece of clay ; now remove it from the fire, and let 
it get cool : when cold, take out the pipe, and 
quickly insert a cork, (at the same time remove 
the clay), and lay it by for use. This la called 
Homberg's pyrophoms, and if a little of it be 



poured at any time from the mouth of the ffaN* 'tj 
will spontaneously take fire. 

Into a cup roDtaining 2 drama cf suIphDrie sfal, 
throw 3 or 4 grams of chlorate of potass; tmnt- 
diate combtution and explocdoo will take place, tbe 
chlorine will be liberated, and sulphate of potaa 
will bo formed. 

If 2 grains of powdered chorcoal and 4 graini of 
chlorate of potasa be carefully mixed in a pii 
paper, then folded up and placed u]>oo an ai 
upon 1>eiug struck by a hammer, a violent 
tion will t^e place. 

fTob* eoMiimmLj 



MEMORANDA. 

Fmrtil in/kfona.— M. de Uumbotdt haancqptif 
presented to the Academy of Sdeneei at 
the name of M. Ehrenberg. spedmena of a i 
aiTjillaceous deposit, lying 20 feet below the 
meut of the city of Berlin, and filled with inf 
still living. Traces of thii subterranean 
observable 3 feet below the bottom of the 
Since 1836, when M. Ehrenberg first called i 
to the immense masses of fossil infusoria, or 
scopic animals, m the more recent formi 
has had occasion to observe, that the organic 
are still so active in the muil of ports and 
that at Swicnemunde, in the Baltic, for cxi 
where above two and a half millions of cubic 
mud were recently removed in une year, ooi 
of that entire mass consisted of microscopic ani 
The moors <^ Liaburg present aocumulatu 
fossil infusoria 2H feet in thickncM. In the 
layer of Berlin, tuunel-shapcd deposits of' 
reach, in aome places, to the depth of 60 feet, 
is no doubt that they are still alive and ca] 
increase. Spontaneous motion may be 
served in specimens token from the greatest 
though Iras frequently than in those near tbe 
M. Ehrenberg, in whose bands the microsoof 
revealed such wonders, is about to produce a' 
on fossil infusoria, similar to that which 
already published on the Living species of nuc 
animals. 

Ittdiffo. — It is said to be proved by cipfrimrni. 
that tbe indigo plant (Polygonum tinctorthm'^ ouy 
he successfully cultivated iu France. AI. Jauna' 
sowed some of the seed in the beginning of April ( 
at tbe end of July he stripped off the leivn of 11 
of the plants, and divided the stalks so itrippet fat*, 
144 cuttings, which, being planted, all sut 
so that by this simple mode of culture, be ii 
his plant tenfold. The leaves of the origL 
plants, yielded 1,400 grammea (about 22 
indigo. 

Aftaic of Kaiurr. — Gardiner, in his 
Au^urp, has put into notes the songs cf t 
fairda, and twenty animals. Also nl 
prenlons of human passion and (•■■ 
of eight or ten insects. The r-"' 
on the fecond vpace. The >}■ 
flat, and an aniiwer in G. 'J !. 
crickft are in B. The bux of a v- 
The wings of the Hmue-fy are P in 
The hHmbte-bw ii ao octave lower. TLa €Oci<h 
is F below the line. 

Water is a better conductor of sound thaa tlf' 
Wood also is a powerful conductor of sound, tai o 
is flannel or ribbon. 



BonmuaftcaUm, twhlch sw amwmd Moulhly.) to be aiMrvn»d te Ibe Ediier.ai W, Cotlaae Owrss Mikr Kad 
£duibui|b. J. MsMsiii—citi-gow, D. Dnict.-Uv,rpw», q, p,iMr. -^ «•» •" 



Bcai^ 



m 



MAGAZINK OF SCIENCE. 



NEW INSTRUMENT FOR CUTTINO SEC- 
TIONS FOR THE MICROSCOPE. 
Sir, — Annexed I b«§ to band jou sketcheft of an 
isuU-umcDt 1 couitructtfd lome timo liacr, for the 
purpote of cutting icctiuoji of wood for (he micro- 
•cope, the size and simplicitr of which will, 1 ihink, 
prove a lofficient recommrndatiQa to a place in your 
ptgoa, in addition to what ho* already ippeAted. 

Your intcreating paper on the tubjcct in toI. I, 
page 145, leavee uothioK hut descriptiun necKiaary 
ia tbia caae, ns the application ti tb« wme in both ; 
this the reference will in tome meature lapply. 
It abottld however be metitioiied, that the mile acrcw 
C, ia tapped with 25 tbrcada to the inch, so that a 
^ of s tarn equals an eleTation of y^ of an inch, 
^ viv' Vi T^' '"^^ **^ ^°- ^' would aUa be an 
advanUfge if the blade of the knife were nade srmi- 
cironlar, ai it woald be easily and regularly tharpened 
by fixing it on a circular piece of wood, ita own 
diameter, with lerel rd^e, to the face plate of a 
lathe, aud applying the stane or atrop while it wac 
in motion. The blade la made with a curved edge 
to obtnin a sliding cat. 1 am, Sia, 

Faithfully yoara, 
JfMHcy Sotue, fFam'nglon. 7-. O. K. RT LANDS. 

A a hruc plate, 3 inchei in diameter ; B a braaa 
tnbc, H inch lon|r, < both caat in one piece.) C a 
brait acrew, to elevate the wood. D a mark filed op 
10 act a* a ^omen to I I I. E a bath cast upon A. 
to hold the iron set screw F, which itcadies the 
wood. G the bole, into which the wood is inverted. 
H the kniff, which work* on the icrew I, under the 
guard K. lit marki Aled in P, to graduate the 
Ibirkucflft Lif the srctioo cut. K the guard under 
which the knife workii. and M u section of the knife 
blade. Fir. 1, a dnwin; of the instrument, Fiif. 2, 
aaecttooof ditto. Fig. 3, a reverse drawing of ditto. 
Fig. 4. the knife, with the wood holeG in itsreUtiTe 
poijtion. 



RADFORD'S ELECTRO-MAGNET. 
Thi following account of thia truly original instru- 
meot hai already appeared in "The Annals of 
Electricity," from which work we copy it. together 
with the letter of Mr. Stargeon, the editor^ to 
Mr. Radford, on the subject of his invention, iu the 
opinions of wfaoin we fully Bgrce : — 

"Dkar Sia. — Herewith I send you the new 
elertrn. magnet which I commenced experimenting 
upon early in October last, and beg your acceptance 
of it. The drawings will explain its character rery 
plainly : — 

No. 1 being the elevation. 

No. 2 ,, the Tcrtical section. 

No. 3 „ the convoluted fnce. 

Y( is nine inches in diameter, and the skeCcKes 
being drawn to icaie the otlier dimensious can be 
asocruioed eaaily. 

"ni* magnet weighs, exclusive of the copper coil, 
■nd the keeper, sistrtni pounds and two ounces. 

The coil is a bundle of twenty-three small copper 
Wres, and weighs two pounds two ounces. 

The coil is covered with cotton tape. 

The keeper weighs fourteen pounds fourteen 
ounces and three quarters. 

The depth of the convoluted groove or reoeas, 
is ^ of an inch and \ of an inch wide. 

The width or breadth of the metal between the 
grooves, as shown in the aectinn, is half an inch. 

The thickaas of the msgnet is one inch, at the 
putiiUo edge, and ibout J in the centtt. 



Before it wu finished, an expcrimrat wai nuk 
on the 3rtl of Drtx^mher, 1840. and it anafiui 
load of 2 1 41 pounds, with eight of your battery] 

The greatest weight was lifted on the 17t 
Deccml>er last, by a battery of yours, with twtlfs 
jars, snd the weight sustained wti 2500 poondl 
avoirdupois. 

If you think this worth a place tn'yottr *'Aitiul^*' 
I shsU feel obliged by your insertion of iC. 
Yonra, faithfully, 

ioftcrn aAppal 

Mr. Sfvrytffn't Anncer. 

"Dr AH StB. — By yonr kindness in preset' 
this piece of appsratos, which, amotir«t ' 
favors, I take a pleasure in availinj 
opportnaity to acknowledge : you : 
potsetsion of the most curious at 
magnet that has ever yet appeared >- 

science, or ever has been placed lu .... i.. _ 

philosophy. 

The convoluted 6gure of its face U not only a 
great curicksity, but a perfect novelty in mscneticsi 
and the unusual arrangement of its poles, both «f 
which are on the §ame convoluted sin; 
(which forms the face,) one pole ocupyin 
length on one edge, and the other the whui'- 11 
of the opposite edge : together with its great 
render it a piece of apparatus of estr&itr 
character and greic interest ; and will, 
command a great deal of attention amonk; 
magnetiati. Yours, tnily, 

w. rrriLaicv,' 



TO FIND THE FOCUS OF LENSES AWB 
SPECULA. 

Thk focal distances of lenses are easily discomvA 
by experiments, and, among othera, ire bait 
lected the following : — 

1. Wlien the focal length of the lens d 
exceed two or three feet, it may bo found by 
the lens at such a distance from the wsl 
opposite a window sub, that the image of (hr 1 
may be distinct upon the wain»cot ; and tbia 
taoce may he considered as the focal length of 
lens ; but if the focal length ii great, the foctta 
be computed by the. SQbtequenC rule. 

Rule. Measnre the distance between t>»»» lm§ 
the objcfct, and also from the im8K;<- 
distancea together and divide the | 
sum -, the quotient will give the focKi ui-v«(i<ie 1 af| 
the square of the disUnce of the otaaemd tbatMt 
dirided by the dtstanco of the object fttn A* 
image will give the excess of the observed fccn 
beyond the true focol distance. 

2. When you tind the focus by making a etodll 
the object, and the paper for receiving its unsj^ M 
that when the image ii most distant the leoi aury 
be exactly between the other two, tl^eii hilvf IW 
distance between the object or iu image and tk 
lens for the focal distAnce. 

3. If a small hole, about oae-fourtb orooe-ei^A 
of an inch be made in the window abutter of 1 
darkened room, and a lens and piece of p>p9 te 
held behind this hole at proper distances, ib*pU« 
where the image of the hole is most distinct niiyl>* 
determined very critically, and from them the ^*td 
length may be found by the foregoing mle. 

4. By the sun's image : Place the leni so ihtfiU 
axis may point as near as possible to the son , cbm 

\ VaV^% % ^»^ (9^?osttc thereto, thr bununj pO»li 




MXGAZiNE OF SCIENCE. 



or whm; thr imnge of tht: sun ii BroitlleBt, rmd the 
Umb most dUtinct is tlie focus. Tbii roetbt>d is 
inKl!i<i«nc|j uccuratr for uprcUcle );Us»p», und lucli 
M are broad m proportion to their focal length : 
bni iritl nnc nniwer fur lentes of a long forui, unlets 
thtj ATu eulticienUf long to exhibit the solar spots; 
twCMoae in these cues the imiD^e is ontjr a glare of 
light without diitinctuesi ; but the iocoDTcuieoces 
VMj be remorrd bj the following method : — 

6. Cover the lens with a piece of pastebourd or 
piper, and mnke two round holes therein at an etjuiil 
distance from the edge of the lens and on one of its 
duiB«teri. The lens being thus covered, point its 
AXIS to the sun; now if a paper he held behind the 
Imc. joq will And the two circles, or white spou, 
prDdaccd by the (wo holes, gradnally approach 
never to oach other as the puprr is moved farther ; 
«t Ust thef will unite, and if the paper be moved 
still further tbey will again sepamte. Tlie distance 
of (he paper from the glass when the circles unite 
beini; meiiured gives the focal distance. 

To Hnd the focus of a plano-convex and n plano- 
concave lens : 

By rxperimentssimilarto the above may b« found, 
1. That the focus of a plano-ronvcx. or of a ptano- 
^oocave glass, is equal to a diameter of its convex 
re surface, that ts, of the whole sphere it 




il the focal distance of a double convex, or 
ibic concave glass, of eqnal eonveiitiea or con- 
carlties, is equal to a semi-dinmetcr of either of its 
nrfaces ; snd consequent!/ that the focal distance 
«f a glass of unequal convexities or concavities, wilt 
have so intermediate strength between a diameter 
and serat-diEmeter of that surface which is must 
4ftnvex or concave. 

To measure the focal distance of ■ globe of water 
sad of glass : 

Take a hollow globe of glass, or instead of it, a 
Ibln round (lask, or decnnter, and making a round 
hole, about an inch in diameter, in a piece of brown 
|npcr, paale it on one side of the body of the de- 
canter ; and having filled it with water, hold the 
covered side to thr son, that the pcrpendicuUr rajs 
■aay pasa through the middle of the water and the 
emergent rajps will be cullerted to a focus, whose 
Aearest distance from the decanter will be equal to 
Ihe semi-diameter of the body of it, as will apivear 
by receiving the rays upon a paper held at that 
Astaace. That this cfTcct is owing to the water and 
jtoC to the glass, will be evident by emptying the 
decanter ; for the light that then pae^es through the 
bole will be as broad as the bole itself at all the 
distances of the paper from the decanter. If a 
similar experiment he tried with a solid globe, or 
bull of glass, the distance of the focus from tlie 
nearest part of the ball will be one quarter of its 
dianteter. 

To find the vertcjc, or centre of a lens : 
Hold the lena at a proper distance from the eye, 
•ml observe the two reflected images of a candle 
made by the two surfaces. Move the lens till tlitse 
inages coincide, and that point is the vertex ; sad 
if this be in the middle of its surface the glass is 
troly- centered, otherwise it is not. 

Whntrver he the shape and magnitude of the hole 
in the pr»per that covers part of a lens, the *hape 
and msgiiitudc of the image will be the same as when 
Ihe lens is uncovered ; because any small part of a 
poocil of rivs has the same focus as the wliote ; but 
the biit;litite«s will be diminiahfd in proportion as 
the hole in the cover is diminished i hc<»usc tUc 



quantity of light whirh illuroinatr.fi every poiot of a 
picture ia diminished in th^t proportion. 

In order to obt:iin a competent knowledge of rr. 
fraction, and the properties of lenses, the btodeot, 
who has not previonsly been made acquainted with 
mathematics, should make experiment* with lenass 
of different foci, diameters, and colors; the rottni 
should be quite darkened, and the sun's rays ad- 
mitted through an aperture cut in a shutter, or a 
tube for that purpose placed therein, and moveable 
by an universal joint, or ball and socket. Hie lenses 
should be fitted in cells, runnected ton sliding board 
or frame, or adapted to st-mda and frarncs q( wood 
or brass. By such contrivances he may combine 
any sort of lenses together as may be necesssry, 
either separately, or close together: he might also 
have lenses ground to the figure of a meniscus, or 
of swatch glass, and connected in one frame, so 
that fluids mi^ht be included and the propertitra of 
refraction by tluid lenses exemplified. A few ex- 
periments in this manner will afford the most evident 
and entertaining proofs of the laws of refracted rays. 
The dost usually in motion will in the darkened 
room give the various and natural ligures of the 
converging and disrrging pencil of rays. 

To find the focnl length of a spherical speculnoi : 

1. For a coocave speculum. Place the speculum 
so Chat its Axis may be nearly towards the centre of 
the sun. Fmd the barning point, or rnceive the 
image upon a white piece of paper ; and the distance 
between the focus so found, and the vortex of clie 
speculum, is the focsl length. Or. cover the specu> 
luni with a sheet of opaque paper, in which make 
two or more holes, and observe where the beams of 
light, re6ected from these holes unite, and this will 
be the fottal distance. Or, lastly, place the speculum 
St the end of a long table, in a vertical position; 
plnce a candle at the opposite cud of tjic table so 
that its tlamc may be opposite to the vertex of the 
speculum ; then take a piece of white paper and 
having tixcd it to a stick, place the stick in the 
socket of a candlestick flo that the paper may be 
snppnrted at about the sanie height with the candle ; 
then move the paper or the candle forwards and 
backworda till the image of the candle on the paper 
is exactly over Ihe candle itaelf, and the point of 
coincidence is the centre of the speculum. 

2. For a convex speculum. Cover it with paper, 
having two piifhules made, one near each edge of 
the mirror; expose it to the sun, holding another 
paper before it having a hole large enoll^h lo let the 
solar rays pass through to the two pin-holes. Two 
white spots of rellected liirht will be seen on each 
side of the hole : move the paper backward and 
forward, till the distance of the spots be twice the 
distance of the holes in the cover ; and tliat distance 
of the paper from the mirror is the principal focus. 



SCULPTURE IN GREAT BRITAIN. 
Trs thousands who visit our annuil eihibition si 
the Royal Academy, and oilier giiUeries where 
sculpture forms, if not a principul, a large jwrtion 
of the collections, are in total ignorance of the mears 
by which such objects ore produced. Tlie general 
belief is, that the stntue, or group, . hewn withoi t 
previous labour from the rough block, is completed 
st once by the sculptor, and that the greater the 
finish or smoothness that may decorate the work, ll e 
more talent is msnifested and credit due ; but with 
the artist and the cdvicfltcd in art, it is simply con- 



396 



MAGAZINE OF SCIENCE. 



lidertd a mechsnicAl ttrmioation, unworthy, in erery 
retpeet, of coDsitleration, milcss npplicnble to a 
weU'Srlected tubject, wril told, ind with jiiilgmenl 
drawn; and eren thrn, a* a pleasing auxiliary only. 
Mind and f4>ntiaieDl are thf chief; and though cer- 
tain niKtertHU msr he mnri; plcairing to Lbe eyr, and, 
In many cnses, enhance the |;enenil effect, stilt the 
trork, without tfaeM requiaites, would be, in piace of 
art, thftt of mfehanirni Inifour. With the multittide, 
nay, with many educated people, an impreaaion 
c3ri»*l», Miat the whole art ofatataary lies in the r»e- 
mf ion of the marhle, a truth evinced hy the manifrtt 
indiffi-'renr* which may be obaerved at our exhibitions 
for the^/na/er prudnctions of peuins, while triSea 
wrought in tiie more expensire material riTet atten. 
tinn, and draw forth exprefvions of the greateat 
adniiration. Sculpture has not only bten long a 
znisunderatooil, hut a nri^lectrd art. Let as risit 
thr numcroua galleries and cxhibilioQ-roomi of our 
own roantry, and w« ahall then obtain suHicipnt 
proof of the fact. Our Royal Academy, our Britith 
Iruititution, and the SufTolk-street Gallery, are all 
infitanfes. The National Gallery, though hung 
throughout with picturex, boasts on koklt specimen 
of tlie Bister art 1 At Mftnchestcr, Liverpool, and 
Birmingham — indeed, at all our prorinciat exhibition! 
•^the accommodation fur sculpture is totally nej;- 
lerted ; and though rrpeated premiuras are offrred 
for the eneouragemeot of painting, in no case has a 
corresponding feeling been erinced for tlie patronage 
of statuary. Let ua visit Paris, and the same neglect 
hecoraes apparent. Windows, far beneath the 
many gloriona works of antiquity which adorn the 
Louvre, destroy the mastery with which they are 
wrought ; though on prore«ding to other hall?, we 
find erery accommodation afforded fortheej^hibition 
of pictures. Milan, Bologma. and Florence are 
eipinlty regardless of their statuary tn reapect to 
light ; and etren (in many instances) the Eternal City, 
the mart of sculpture, is open lo the same remark. 
The Ia4t alight which this noble art sustains remains 
untold. Sec our daily and our weekly papers, nay, 
our journals of nrt and sdeiice— see the column oiler 
column noliring the productions of the pencil, and 
then the infantite paragraph, stating simply that 
iculpture too ia there. 

The firat idea of the sculptor ii traced either in 
day or on paper ; a small and rough sketch of the 
aubjert he wishes to produce, in which he considers 
welt his talc, and the beat mode to convey it, the 
moat agreeable position for his figures, and the gene- 
mi effect of the whole, totally neglecting every 
appearance of detail or amootbnefs. When tfaifl 
draught ia rompleted agreeably to his wishes, he 
commences (with the assistance of his workmen) to 
pile up a mass of clay the size of the object to be 
ponrtrayed, rendering it firm and ste.idy by the 
addition of irons and frame-work, accitred to the 
»tand on which it reiits ; and on the careful comple- 
tion of this — the model — depends the correctneas 
and beauty of the marble. It ia at this stage that 
the draught or original idea is reconsidered, copied, 
and, with the assiatance of the human ligure, more 
minutely studied and carried oo to completion. The 
moist nature of the clay renders some mode ne- 
ceaaary for the preservation of the model during the 
progress of carving, or being copied in msrble, and 
ihia it effected hy moulding and cjuting, as follows : — 
Tlic clay— for instance, n statue — ia at first covered 
nn Ihf. front half only, from the summit to tin* base, 
wjth it /nijitureofpliistcr and water, which m.-iJIowcd 
lo hccome hud, or 6ct, prcviouhly lo lUc rciaAiumi 



portiijn of the figure being ravrred, when the idf]i«etj 
is entirely coated, and the mould completed. A] 
sufficient time having elapsed to rendf*r the 
firm, it ia carefully removed in two parta ^m itm] 
clay, when an exact representation of the aCatas ii 
sbown in reverse. These, being thoronghly cleaiiied< 
are placed securely together, and filled with plastv 
of a finer nature, and in turn an impression it lakd 
of the mould ; this being carefully cut away, 
a east, similar in every reipecc to the origiaal 
The plaster cast is now placed in lb« haadi 
mason, who by means of a machine proceedt 
the pointing or roughing out. By this pi 
waste lUme gradually diminishea, and the form di 
beooinea more and more apparent, naril wiihio 
inch or less of its intended surface, when it is ibIi* 
mitted to the chisel ot the ikrulplor'a mnrfi abb 
assistant, who carries it still nearer to the p*^wcim 
of (he model, and prepares it for (he final 
of the master. — The Art Cnioiu 



CHANGES OF THE KALEIDOSCOPE. 

TUE propetty of the kaleidoscope, which has eidldl 
more wonder, and therefore more conlroveny diaa 
any other, is the number of combinations or cl 
which it is capable of producing from a sma 
her of objects. Many persons, entirely iguoi 
the nature of the instrument, have calculated Qi 
number of forms whicli may be crcmted fron a 
certain number of pieces of glass, upon the ordinaiy 
principles of combination. In this vny it fbllovf, 
that twenty-four pieces of glass may be combifllrf 
1391724288887232999433128493402200 times, it 
operation, thr performance of which would tlht 
hundreds of thoasanda of millions of yeara, evra 
upon Ihr supposition that twenty of them w*n 
performed every minute. This calculatioD, tur* 
prising OS it appears, is quite hise, not from beuf 
exaggerated, but from being far inr('rji>r to Che 
reality. It proceeds upon the sappobuiim tbsf av 
piece of glajis can ethibit only f'nr figure, and thai 
tiro pieces can exhibit only ttfo figurca, whereas tl 
is obvious that the two pieces, though they ob Mlf 
be combined in two ways, in /Ac aance timtyht fi^, 
yet the one can be put above and hetow the otfc«r, 
BS well as upon its right side and its left side, and 
may be joined, so that the line connrctinx tUrir 
centrea may have an infinite numbiT of po«ritioa* 
with respect to a horizontal line. It follows, luderd. 
from the prinriplea of the kulcidojit^^pe. that (Aon^ 
fMie ol/jeet i» utedf and if that objerf it a mttin* 
malicai line triUiovt Ureailfh, the in*tntmnri tM 
form on infnite nvmher of fiffttrts frvm thu ti»ftt 
tine. The line may be placed at an tnfiuitc numbfr 
of difltunces from the centre of the aperture, and 
equally inclined to the eitrcmitiea of the redeclora. 
It may be inclined at an infinite variety of snglet to 
the radii of the circular field, and it may be |<Uccd 
in an infinite vsricty of positions parallel to aoy 
radius. In all tliese cases, the kaletdoacope wit) 
form a figure differing in ctiaracter and in msgni* 
tude. In ^e first case, all the figures are polyguai 
of the same character, but of diflVrenC »ixr>. In 
the second case, they are atant, differing from rad 
other ^in the magnitude of their tialient and rr* 
entering angles ; and in the third case, tbey fora 
imperfect figures, in which the lines unite at 001 
extremity and are open at the nthrr. 

If, instead of ntipposing a mnthcmatir ' 
^^ tUe ob|cot, we Uke 4 nttj/tt pi^rt "t 



^ ^ 



MAGAZINE OF SCIENCE. 



^7 



fUn, with in irregiilBr oatline, we shall h«Te fio 
difficulty in pcrcfliTing, from cxpcrimcDt. that an 
tnfiiiiir Tiripty of figares may be created from it 
•Irmc. Till* STBtrm of cndliiss cbangnt is one of 
thr mo«t extraordloary properties ol* tlie kalrJdo- 
%eopc. With a namber of loose objecti, it is im- 
pnA».kl>la to repiodaoe any 6gure which we bive 
tulmiird, >Vhen it is once lost, centuriea may 
clnae brfore the larae combination returns. If the 
etlt)*ctJi, however, are placed in the cell, so as Co 
1ui*e trry little motion, (be same figure, or one very 
tt«ir it, ni.ir, witkout difficulty, be recalled ; and if 
tb^ art abiuluCety fixed, tbe Bame pattern will 
rr>:nr in every revolution of the object plate. 

ANCIENT MASONKY. 

'- • masonry known to ua is probably that 
< I ; 'i«ii», which ia ehietly reoiorkable for 

iJii. .: .- size of the stones employed, luid to 

hm frrcjucntly thirty feet in length : the weight of 
theae miusrs rendered the use of mortar unueces- 
•Ary. OQoe placed, they were never likely to be 
removed ; whilst their sixe also rendered the use of 
tlie arch in must casea unnecessary, a single stone 
bciDii: lit ffi /lent to cover almost any opeoiug that 
they rnjuired* although there are some vnuUi ron- 
»:rwted of large masses of stone laid bonxontatly. 
and oTerlapping each olber until they meet in the 
ctn'.re. 

or Cyclopean masoory tbe most celebrated re- 
Duioa are the wnlls at Tiryns and Mycenie ; their 
date is unknonn, but as they are alluded to by 
tiomw. they arc necessarily of high antiquity ; 
tttne walls arc formed of large ami irrrgularly- 
•haped masies of stone laid together without mor> 
ijr, md the interstices filled with smaller pieces. 

Tynhrriian or Etruscan masonry consists alio of 
larg« and irregularly-shaped mosses of stone, but 
fitted together with considerable exactness, so aa 
Dot to admit of smaller stones in the joints or iuter- 
Aiee* : of this kind of masonry many specimens 
ffxiat omong the ancient rrmoins of Greece and 
Italy. Thr next improrenirnt in mattonry appears 
to consist in working the atones sollicientty to render 
the ht>rizotital Joints (or bed) in ^reat measure llat 
and trns, the vertical joints being reduced to a 
Binight lurhca only, and not made perpendicular; 
md the courses also are more or less irregular; 
oamplra of this kind of masonry arc to be founit 
«C Fiesole, I'opolonia, and many other places. All 
of these kinds of masonry were put together with- 
oct any kind of mortar. The stooeB also were of 
very large ditnensiuns ; the usual slxe of those of 
tkm walls of Tiryns ia about seven feet by three, 
htA some are larger ; »o also are they in aome of 
tkt other siM-cimens. 

In llie ruins of Palmyra and Balbec all traveUers 
ifwo in rrmarking tbe enormoos dimensions of the 
Mooei employed; for instance, at Uolbec, "On 
Ibtt veas aide uf tbe basement of tbe gre^t temple 
tWi the second course is formed of Ktoties which 
W* from 29 to 37 feet long, and about 'J feet (hick ; 
vailar thia. at the north-west angle, and about 20 
fcc< from the ground, there are three stones which 
all ' 182 feet 9 inches in length, by aboat 

l*- ck ; two are GO feet, and the third 62 

* in length." 

I y purposes, the ancients umed several 

Ling, as the "opus inrertum,"' now 
in" or " nibblti" walling, made with 



reticnUtum," loeAU&d from ita oet-like appetrtnoe, 
formed with scjuare stouea laid diagonally, and this 
Vitravios mentions as being common in his day ; 
" isodomum" and " pscvdisodomum," which Vitro- 
vius ascribes to the Greeks, were formed in regular 
courses, in the fint all of equal lieighi. but in the 
latter of unequal height t *' emplectum'* resembled 
the two last in external appearouce, but the middle 
of the wall woa of rubble, tbe facing only bdng in 
regular courses : in oil these sorts of masoury the 
atones were small, and were loid in mortar. The 
ancients also frequently erected walls of brick, both 
burnt and unbnrnl. In the erection of large build- 
ings, in whirh large blocks of stone were used, the 
Romans used no cement. In the later times of the 
empire, it appears that tlte masonry called "em* 
plectum" was most commonly used ; Si this kind 
j(cither witli or without occasional courws of tiles) 
iri that which is usually found in this country and in 
France ; the courica arc usually i inclica deep, the 
stones in must instances of rather cubical propor- 
tions, and the joints commonly wide and coarse. 
This kind of masonry also, without the bonding 
courses of tiles, was manifestly osed after the 
Romana were subdued, for it is to be found in the 
walls of the old nave of the cathedral of Beauvals 
(called Notre Dame des Uasses fKuvres), those of 
the nave of St. Rr'mi nt Rhciros, of St. Pierre, at 
Le Mans (if any of this buildiug still exist\, and in 
the walla of tlte keep of the Chuiesu of Lsngeaia 
on tbe banks of the Loire ; none of which buUdinga 
are of Roman date. 

In England, the existence of any remains of the 
Saxon period is doubted by many ^ our best anti- 
quaries, but it would appear without sufficient 
grounds, ae the class of buildings disputed have a 
very diflerent character from Norman work, and are 
equally distinct from Rofaan. The masonry of tbeae 
buildings oonsista chiefly of rude rubble-work, and 
we frequently find Roman bricks worked up irre- 
gularly into the woJis, sometimes in herringbone 
fashion ; but the chief peculiarity in the masonry 
of these buildings conaists of the particular manner 
in which the cut stones at the angles used b.« quoins 
are arranged, called " long and short work." 

In early Normnn times the walls on the inside 
had a nibble face,' and were plaistered, and had 
frequently an external face of rubble as well, and 
perhapa were occasionally plaistered also on the 
outride : when the external face was of oshlar, the 
joints were always coarse and large, and the mortar 
most commonly made with very coarse unsifted sand 
or gravel ; the stones alao sre generally In shapes 
approsching cubes, and vary in depth Gram about 6 
to 9 or 10 inches. During the former part of the 
twelfth century the masonry improved coosidembly ; 
the mortar was made of finer inatcriils, and the 
stones were set with s neat and close joint, but they 
had still an approach to a cube in their shapes. 
Rubble has been used at all times up to the present 
day. Herringbone work has been called by some a 
sign of early work, hut others rrgnrd it rather as a 
sign of late NormuD. Guildford Castle is late Norman, 
and has a good deal of faerringboue work in its 
walls. ** Opus reticulatum'* la occasionally found 
in late Norman work, as at the west end of Ro- 
chester cathedral. There is also another kind of 
masonry sometimes found in late Norman work, 
which appears to bo used by way of ornament (as 
in fact is the "opus reticulatum"), and of which a 
specimen luiiy be found in the tympanum over the 
south door of tUe %m»\V OitWCiVJCi^ vcA v<i»vi>»- 



398 



MAGA^IINE OF SCIENCE. 



ehipel of West Uytht ; perb«p« it miy be calird 
herringbone uUar. In th« nire of (be cathedral 
at Bajeux ore meral Taneties of maionry intro- 
duced to ornament the walls, ail which a/e late 
Norman. Afler the expiration of (be Norman ityle 
there U aeldoDt if ever, say fixed character in tbc 
naaonrj to evince tlie date of a building ; but it 
may be obserrcd. chvt in the fonrtcenth century tin 
■tonci emploved are frenerally smaller thui at a 
■uliMHiii III period, and that there ia generally a 
ntrltcd difTcrcnce between modern masonry and that 
of tb*? middle «ge«, which the eye at ooce detects, 
and which ia often uaeful ia poinliog out iuertious 
and aluritioDi. 



QUALITIES OF BAD PAPER. 

In order to increase the weight of printing pnpei^ 
aome manufsctorers are in the habit of mixing ml. 
phate of lime, or gypsnm, with the rag to a great 
extent. 1 hare been informed, by an authority 
tipon which I place great reliance, that aome paper 
codUidv more than one-fourth of its weight of gyp. 
anm ; and I lately examined a sample, which had 
the appearance of good paper, that contained abont 
12 per cent. The mode of detecting this fraud ia 
exceedingly simple : bum 100 grains, or any given 
weight of the paper, in a platina or earthen crnci- 
tile, and roiitinne the heat until the residiaro be* 
comes white, which it will readily do, if the paper 
is mixed with gypsum. It ts certainly true that all 
paper contains a small quantity of ineombustiblo 
matter, derived from accidental impnriCiea, but it 
does not amount to more thin abont one per rent, ; 
th« weight, then, will indicate the extent of the 
frand."— /?/-rtnrf*. 

The prorc«9or just quQ^d also mentions a cir- 
cumstance of a Birmingham button-maker, who had 
a large quantity of ncwIy-made buttons, bo much 
Umished as to be unsalrsblf ; and upon examining 
Into the cause, it was found to be owing to thetr 
being left in the paper, in which the buttons were 
wrapped up, a considerable quantity of chlorine, or 
oxymnriatir acid, which is used in the bleaching. 
There arc very few goods that would not be injured 
by tht' action o( ohluriiic. — A colored paper roanu- 
factorer would find it difficult to fix any vegetable 
color upon paper so impregnated — and the loss to 
him might be very serious. Great caution is there- 
fore necessary in the pnrchastog of paper for luch 
purposes. 

ENGRAVING IN IMITATION OP BLACK- 
LEAD OR CHALK. 

A RRMARKABLY good polish musl be pot on tliecop- 
jter with an oil rubber and crocus-martia well ground 
in oil ; after which it must be cleaned off with 
whiting, and then rubbed ntth another clean rag. 
You are then to pour over ynur plate the solution 
lo cause ground, which is m»de as follows : — 

No. 1. Three ounces of Burgundy pitch; one 
ounce of frankincense. Tliese are to be dissolved 
in a quart of the best rectified spirits of wiue, of the 
strength to tire gunpowder when the spirits are 
lighted. During the course of twenty-four houra 
this composition must be repeatedly shook, until 
the whole appears dissolred ; then filter it through 
blotting paper, and it will be At to use. In pouring 
on this ground, an inclination most be given to the 
pUt£ tJist tbc su/icr/Iuoua pari of the comviotiUon 




may run off at the opposite aide ; (ben place a pirn 
of hlutting paper along this extremity. lh«l it maf 
surk up the ground that will drain from the plala, 
and in the course of a quarter of an hour tbc spirit 
wijl evaporate, and leave a perfect ground that will 
cover the aarfacc of the cojfper, bard and dry eiiuagh 
to proceed with. With an exccedir :' " ' 'icl- 

lead pencil sketch your drsign on tl . >nd 

when finished, take a pea and draw -a- 

ing composition, resembUug ink : if you wiah yov 
outline lo be tiiin and delicate, cause the 
draw with to be made with a sharp point ; 
intend to rrpreaent chalk drawing, a very s 
and broad-made pea will be nccraaary, or a 
reed. 

No. 2. Composition, rrsMobling ink. to draw 
design on copper. Take about one ounce of t 
or sugar-candy, add to this three burnt corks, 
duced by the hre to almost an impalpable 
tlien add a small quantity of lamp-b!aok to 
to these put some weak gnm-wHter, (mada 
arabic,) and grind the whole together on 
with a muUer : keep reducing the ink with 
water until it flows with eaae fmm the pen or 
To make the ink discharge freely from I'l- f'" -• 
must be scraped rather thin towards the ' 
nib, on the bark part of the quill, and if 
is thick, reduce it with hot water. Ua^ 
the drawing on the copper with this roi> 
yoo will dry it at the tire until it becon 
then varnish the plate all over with turpc:- 
niah (No. 3). It will now be nerrawiry i 
varnish (hat ia ps»^d over the plate. •' 
will take three or four hoars at leatt ; but 
depend on tjic state of the weather ; for if i: stiould 
be iutensely hot, it ought to be left all ni^Ut la 
harden. Now the varnish is presumed to be saS- 
ciently hard, you may rub off the touches made wHfc 
the foregoing described ink with saliva, and u*e rowi 
finger to rub them up ; should it not romc off vMy 
freely, put your waliing-wax round the margin of 
your plate, and then poor on the touches some wsrok 
water, but care must be tsken it in not ton hot 
The touches now being clean taken off, wash tkt 
plate well and clean from all impurities and sediiBaiiA 
of the ink, with cold m/I water, then dry the plctB 
at a distance from the fire, or else in the sno. tM 
when dry, pour on your aquafortis, which shodtf 
be in cold weather, as follows: — 

To one pint of nitrous acid, or strong aquafortis^ 
add two parts, or twice its qunntity of foft watsr. 
In hot weather, to one part of nitrous ti-id j id fhrw 
of water. In every part of this pr- !'«rl 

or pump water. The last proecfts • wtth 

aquafortis must be closely attended lo. bmihiiift tf 
all the bubbles that arise fn>m the actioM of lli 
aquafortis on the copper. 

In summer time it will take about tarenty minnlfl 
to get a sufficient color : in winter, perhaps, half as 
hour, or more. All Ihia mu&t depend on tbc aCali 
of the atmosphere and temperature of your roo» 
If any parts require to be stopped oat, do the aatas 
with turpentine varnish and lamp black, and wttk 
a camel-hair brush posa over those part* 
aider of sufficient depth ; distuimt m. 
receding from the sight of course oui;h( i.u-. ..■ ^ — 
deep as your fore-grounds ; occordlngly yen wit 
obliterate them with the foregoing ramwh, and lliV 
let it dry, when you will apply the aquafortis a mwinrf 
lime, and repeat this just as oflaa as you wisii t> 
procnre difiiercnt ilt-grees of color. Kvory dnf 9* 
ukc off the aqiMfortis the pli« nuit bt wuM 




MAGAZINE OK SCIENCE. 



2ii'J 



tvio* with toft witcr. and then Mt to dry u before. 

, ^ atcertoin the depth of your work, you should rub 

• unall ptrt with a piece of rsg dipped in turprritine, 

and tticM apply the fioeer, or a piece of rug rubbed 

on thf< oil-rohber, to the place io cleared, and it wiU 

k'tvf TOT iorae idea of the depth. The walling-wax 

off by applying a piece of lighted paper to 

•>: of tlie place, all round the opposite parts 

fif the marj^n where the wax ta placed, then let the 

plale eool, and the whole of the grounda, ficc., will 

csiUy come otT by washing the plate with oil of 

t«rpentirie, wliich muit be used by passing a rag 

h\.-L wardi and forwards, until the whole dissoUea, 

:i to be cleaned off by rags ; and care must 

■ .11 that no part of the tarpentine ta left 

bougtuif about the plate. The plate should only 

paa« once through the presi. 

'' -fioru retpecttng CrotmA.— No. 1. The 
11 hot weather roost have an addiUoual one- 
VU..U ..> ipihlaol wine added 10 it for coarse grounds, 
to represent chalk ; and one-half added to it for 
floe gToands, to represent black-lead pencil; and 
alwaya to be kept in a cold place in lummer, and 
A mrHlerate warn situation in winter. 

\i any parts are not bit strong enough, the aame 
ftoeeas is to be repeated. Gum water must be made 
b the proportion of faalfaa ounce of gum-arabic to 
I quarter of a pint of water. Turpentine varnish 
ia .ri.n r.osed of AH ounce of black rosin to an eighth 
.1 pint of spirits of turpentine ; if the weather 
"Mrely warta, it ought to be made with a sixth 
of a pint of spirits of turpentine. Tracing rag 
>ntd be made of a piece of Irish linen, not too 
Tnrn, the surface of which is to be rubbed 
>ther rag dipped io sweet oil, just sofficient 
iu (cLiin a imall portion of vermilion or pounded 
led chalk. This must be placed with the colored 
part towards the ground of the plate, and the draw- 
u^ or tracing laid upon it, which mu^c be traced 
very lightly with a blunt point or needle. 

MAKING OP DISTILLED WATERS. 

Rre»ervation qf Jtowera /or ditttiliation. — Rub 
three pounds of ru»e-leavea for two or three minutes 
h vitb a pound of common ialc. The fiowera being 
trui^ed by the friction of the grains of salt, form a 
paate which ia to be put into an earthen jar. or 
IBto a water-tight barrel. The same process is to 
be repeated until the vessel is filled, so that all the 
naea may be equally salted. The vessel is then to 
be fthut op and kept in a cool place until wanted. 

For diiiillatioD, (his aromatic paste is, at any 
•eoBon, to be put into the body of the still with 
twice its weight of water ; and when heat is applied, 
fhe oil, or easeotisl water, is to be obtained in the 
common way. Both the oil and water, are in this 
way produced in greater quantity, than by using the 
Icavea without the salt: besides, the preserved paste 
iritl keep ita flavor and strength unimpaired for 
•everal years. 

Other flowers, capable of affording essential oils 
nay also be treated in the above-mentioDed wsy, 
with economy and advantage: as there ia thereby 
DO occasion to carry ou a hurried process in the 
heat of summer, when these arc in perfection. 

1. Plants and their parts ought to be fresh ga- 
thered. When they are collected fresh, such only 
nnst be emjdoyed ; but some are allowed to be 
«aed dry. as being easily procurable in this state at 
at] times of the year, through rather more elegant 
waters might be obtained from them whilst green. 




2. Having bruiaed the subjecia a Utile, pov 
therean thrice ita quantity of spring water. 

Tliia quantity la to be diminished or iDereosed, 
according as the plants ore more or leas juicy tbsu 
ordinary. When fresh and juicy herfaa are to be 
distilled, thrice their weight of mter vriU be fully 
sufficient, but dry ones require a much larger quan- 
tity. Id general, there ahould be so much water. 
that after all intended to be distilled has come over, 
there may be liquor enough to prevent the matter 
from burning to the still. 

3. Formerly, wuie vegetables were alightly fer- 
mented with the addition of ycaat, previous to the 
distillation. 

4. If any drops of oil awim on the surface of the 
water, they are to be carefully taken off. 

5. That the waters may be kept the better, about 
one-twentieth part of their weight of proof spirilr 
may be added to each, aft<?r they are distilled. 

SiiUtfor simple it«/er*.— The inatrumeuts chiefly 
used in the distillation of simple waters are of two 
kinds, commonly called the hot still, or alembic. 
and the cold still. The waters drawn by the cold 
still from plants are much more fragrant, and more 
fully impregnated with their virtncs, than those 
drawn by the hot still, or alembic. The method is 
this : — A pewter body ia nispeoded in the body of 
the alembic, and the head of the still fitted to the 
pewter body ; into this body the mgredients to be 
distilled are put, the alembic filled with water, the 
still-head luted to the pewter body, aud the nose 
luted to the worm of the refrigeratory or worm. 
The same intention will be answered by putting the 
ingredients into a glass alembic, and placing it in a 
bath-heat, or balneum moric The cold still ia 
much the best adapted to draw off the virtues of 
simples, which are valued for their fine flavor when 
green, which is subject to be lost in drying; for 
when we want to extract from plants a spirit so light 
and volatile, as not to subsist in open air any longer 
thau while the plant continues in ita growth, It is 
certainly the best method to remove the plant from 
its native soil, into some proper instrument, where, 
as it dies, these volatile parts can be collected and 
preaerved. And such an instrument is what we call 
the cold still, where the drying of the plant, or 
flower, is only forwarded by a moderate warmth, 
and all that rises is collected and preserved. 

Expeditiout metAod qf dutiitiug simple waterg. 
—Tie a piece of mualiu or gauze over a glaxed 
earthen pot, whose) mouth is just large enough to 
receive the bottom of a warming-pan ; on this cloth 
lay the herb, clipped ; then place upon them the 
warming-pan, with live coals in it, to cause heat 
just enough tu prevent burning, by which means, ss 
the steam issuing out of the herb cannot mount 
upwards, by reason of the bottom of the pan just 
fitting the brim of the vessel below it, it must oe> 
cesaarily descend, and collect into water at the 
bottom of the receiver, and that strongly impregnated 
with the essential oil, and the salt of the vegetable 
thus distilled ; which, if wanted to make spirituous 
or compound water, is easily done, by simply adding 
some good spirits, or French brandy to it, which 
will keep good for a long time, and be much better 
than if the spirits had passed through a still, which 
must, of necessity, waste some of their strength. 
Care should be taken not to let the fire be too 
strong, lest it scorch the plants ; and to be made of 
charcoal, for continoance and better reguladon, 
which must be managed by lifting up and laying 
down the lid, as wanted to increate or decrestc the 



400 



MAGAZINE OF SCIKNCE. 



• 



ilegreos of heat. The deeper the earthni pan, the 
cooler the »eiMn ; anJ the lesa 6re at Ant (after. 
wmrda to be fradiiBlly raiBtid), in the greater per- 
fection vrtil the distilled water he obtflined. 

As the more moveable, or volatile parts of ve^- 
tablcfl, are the aqueoua, the oily, the ^ummy, the 
resinoui. and the aaline, thcsa are to be expected 
in the waters of this process ; the heat bert; em- 
ployed being so great ai to burst the vessela of the 
plants, some of which contnin 50 large a quantity of 
oU, that it may be tpva swiniiuiii^ on the surface of 
the water. Alibotigh a amail quuotity only of dis- 
tilled waters can be obt«iDed at a time by thii con- 
fined oireration, yet it compenaates in streofttb what 
is deficient in quantity. Such liquors, if wcU corked 
op from the air, will keep good a long time, espe- 
cially if about a twentieth part of any spirits be 
Addcdfiii order to preterre the same more efTeclually. 

CTub€ ctmlinued J 



OP FRICTION. 

Ir a horizontal plane were perfeciftj smooth, a body 
would be free lo move upon it in any direction by 
the least force applied to it. But however smooth 
bodies may appear to the eyo, numberless inequali- 
ties are discoverable by means of the QHcrosoope ; 
in consequence of which tlic protruding parts of oao 
body fall into the cavities of the other, and so be- 
come locked together ; thus rendering necessary 
the appUcatiou of a new force to raise the prominent 
parti of the one from the hollows of the other. 
This is what is called friction. 

Friction is greater in bodies, in proportion to 
their weight or preaanre against each other. It also 
increases in proportion to the velocity of the moving 
bodies. 

A piece of smooth soft wood, eight pounds m 
weight, moving upon a smooth plane of soft wood, 
at the rate of three feet every second, has a friction 
equal to above two-thirds of its weight. Soft wood 
upon hard wood bu a friction equal to one-sixth 
part of its weight ; and hard wood upon bard wood, 
about one-fcighth part of its weight. 

In wood rubbing upon wood, oil| gresse, or 
black-lead, properly applied, makes the friction 
two-thirda less. 

^Tien polished steel moves on ateel, or pewter 
properly oiled, the friction is about one-fourth of 
its weight — on copper or lead, one-fifth ; on brass, 
one-sixth. Metals have more frictioo, when they 
move on metals of the same kind, then when on 
different metals. 

The friction of the wheel and axle is in propor- 
tion to the weight, velocity, and diameter of the 
axle. The smaller the diameter the less the friction. 

In the wedge and screw the friction is great. 
Screws with sharp threads have more than those 
with square threads, and endless screws have more 
thon either. 



. IMPROVED CAMERA OBSCURA. 

(Tv the iUit<tr.) 
SiB.,^1 take the liberty of forwarding to you an 
improvement t have made in the port.-iblc camera 
obscum ; the following cut will assist my intention : — 
Let the usual pieces of wood which arc placed on the 
ride of Llie flap, which shades the gluss pbte or field 
of view be taken away, and the box E. without top, 



bottom, or one side be substituted ; if this t>e msda 
to slide up and down ia the sockets tlmt ilw i«o 




pieces of wood slide ip, and the ground glass be fd 
on two ledges at the top of the box, the focus 
be arranged sufficiently clear, lo be able to 
portraits by the photogenic apparatus ; I have 
BO, and find the pictures 'very distinct. In the 
A is the camera, B the ground glass, C the ref 
D the flap, witliout the pieces of wood, B the 
and P the; flap, to shut down to keep off" the 
(he box is to be puUed up and down, till the 
focus is arranged. Hoping you will find a place hT 
your culumna for this. I reoudn, Sir* Stc., 

KpWAUt f. 



L«fiDO>i.— RrinM by O. PaAaett, «. White HonaLaM, Hll« Eod.— PuhUibail by W. Datrura. tt.Pateriiui 
CommuutcaUon. (wtitcb at^^9wer«d Moutbl>j to b« addresHd to tin i^iUloCiBtzr, toltse« Orvvc. Mik 



MEMORANDA. 

Anhnal Ettctririty.'~-'SiT. Glover has publitbfd 
the following method of receiving the electrical 
shock from a cat. Place the left hand under tht 
throat, with the middlthngerand tlie thumb slightly 
pressing the bones of the animal's shoulder, thea 
gently passing the right hand along the back, aca- 
slble electrical shocks will be fitt in the left hand 
Very distinct discharges may be obtained, too, by 
touching the tips of the ears after applying frictfoa 
to the back of the cat. It will be hardly neces- 
sary, we suppose, to hint how requuite that a good 
understanding should exit! between the ex perin enter 
and the apparattit, lest thocks might be eliciled 
more electric than were to be wished. 

AtnuiJtj>hrrical or Mfleoric Dvst.—Vn>femoT Ra- 
fene&que, of New York, asserts, thatan impererptibia 
dust falls at all times from the atmosphere, and that 
he has seen it on Mount Etna, on the Alps, on the 
Alleghany and Cstskill raouotains in America, and 
also on the ocean. This is the same dust, he as- 
serts, which accumulates in our apartments, asA 
renders itself peculiarly visible in the beams of tha 
sun. He ha.* found it to accumulate at the rate of 
one fourth of an loch to one inch in a year ; b«i hi 
Huch a fleecy state, that it could be compreasad to 
one-third of its height. Hence he lakes thc«vera|^ 
of the yearly deposit at about one-sixth of an inrh. 

CurnpotitioH 0/' the Branxc qf the Ancients,^ 
It appears, from a number of experiments, that the 
bronze, of which the ancients formed their weapoaa, 
nnd other articles, consists of 88 parts of copper to 
12 of tin ; and it is remarkable that the 
mixture of the metaU has been employed in natioaa 
very remote firom each other 

To Whiten Diieoiored PearU. — Soak them in bat 
water, in which some bran srith a little tartar 
alutn have been boiled ; rub them gently 
the hands, which may be conlinnod until the 
grows cold, or until the object is effected 
may be rinced in lukewarm water, and laid oa 
ting paper iu a dark pbce to cooL 

Datrura. tt.Pateriiu«t« Bew. 



THE 



MAGAZINE OF SCIENCE, 

^nti Stbool of ^rt0. 



['■■ u 

165.] 



SATUItDAY, MAKCH 19. »Mft 



riirf. 




SKIPSETS ELECTRO-MAGNETIC ENGINE. 



cr lit. — NO. u. 



40'i 



MAGAZINE Of 5Cli':NCE. 



ELECTRO-MAGNETIC ENGINE. 

C7"i> the hiUtar.j 
Sir.— I send toq an iiccDuiit of a rer; conTenient 
electro -lungnc be engine, which I have conatructed 
for mj own use : it does DOt differ ia priocipte froiu 
that of Mr. Bachboffuer, which yoa dncribed in 
your firat Tolnme, oor yet from otUcra since inserted 
in your Taluiible Magazine, bat il is mure coiivcnirnt 
thui they are. on account of the facility of attaching 
the uiaal electro'magnetic apparatus to it, eipecially 
by the inttodaction of the univeraal diteliarger. — It 
la sft follow! : — 

Z A, are two breti pillon, with holes drilled on 
top of each for the braas wire B. C, a cam or brralc 
with pulley on back of an upright pillar Z, with 
mercury in bole at top to break connection; to oae 
the table, take out the wire B, then put two wires 
and joints, like D, into the holes of A end Z, with the 
table between them. This table you may tbow 
many experiments on. Tbe machine altogether 
answers Tcry well ; It requires a large coil of primary 
wire to make the iron bar a strong magnet to cause 
the bocketa to rotate ; one end of the primary coil 
goes to the pillar with mercury on the top end of it 
at Z, the other end goes to the biuding fcrew £. 
There ii a wire lolHered to pillar A and goes to 
binding screw F ; one end of the secondary coil goes 
to binding screw G, the other cud goes to bmding 
screw H. Put a little powder on the top of pillar 
Z, turn the multiplying wheel, and it will fire the 
powder inalantly ; likewise on the table, if the two 
wires br put in the place of the brass wire B. The 
pillar Z has a iroall cannon screwed in near the 
top, with touch-hole at tbe end, about \ of an 
inch above the mercury.; to Are the cannon, put a 
little gunpowder ou tht; tup of tbe mercury, then turn 
the multiplyiog wheel, and the cannon goes off*. 
The brass wire B must work clear in the holeon top 
of the pillar Z, not to touch the pillar any where only 
on the top of the mercury. If you think the above 
worth your notice, the iniertioa will oblige, y^nrs, 

Mitt Gate. Rtpon. W- SKIPS* J^ 

MICROSCOPIC OBJECTS. 
We have repeatedly been referred to for a list of 
microscopic objects, such as will at once show the 
powers of an instrament, yield initraciion and 
amntemeut, and yet such, that amateurs io the 
country may procure and mount them for their Own 
use. We have somewhat neglected this subjact 
lately, because we often ailvertrd to it in the first 
volume, but the description of a microscope in our 
last pnrt has again drnwn upon a> several inquiriei; 
we shall beat ansncr them, by referring our readera 
to an excellent little work, entitled " .\ List of Two 
Thousand Microteo|iir Objecta," by Mr. Pritchard, 
the weU*known author of several works on infusonsl 
■nimali, and a celebrated maker of microscopes is 
Fleet Street. We have carefully looked over the 
list, (which ia published at a thUHng only,) and are 
obliged to testify to the choice selection of objects, 
aa well as the other interesting matter which it con- 
tains on mouoliog, collecting, &c. To show the 
natiirr of the introductory remarks, we take Che 
following almost at random : — 

" Tbe eggs of birds arc oval, but those of insects 
aisume a vast variety of forms : acme are furnished 
witti covers : the surfaces of many are elegantly 
emboased or lluted, whilst others, as tbose of the 
Bug {Vtmes lectutarint,) have their snrface cu- 
riotuiy granulated. Those given in the list will be 
ftnutd Bmoug the moat ialerviUag fot [avcco&cov\« 



observation. They require in most caacs to bt] 
viewed by reflected lif;bt, and with modenle «■< 
plification ; namely, between 20 nod 00. 

'* Hummi ffair.—\n tbe adult, tbe fnctiftn oCT 
hairs against each other is such, that their 
atrtictare ifc seen with difficulty. From a 
ration of this circumstance, and finding lh« 
of infuntft freciuently matted, or felted logrtfc 
smatl knots, after washing, arism? from iU ' 
surface, i wna induced to uamtne the tatter* 
finding the asperities much more decided than & 
that from the adult, I procured some specimf-ns IVisa 
a babe only two hours old. in which the iaibncstid 
structure was very distinct. On muuutinfc. bowetw, 
a specimen of this hair in Canada balsam. (Df 
exterior characters were obliterated. 

•' Hair of Caicrpillart.—Thc hairi of 
species, when eznmined by the micros(»pc. 
branches of tbe bisck thorn ; and othera arcfg 
with branches on each side, like a fan, ri 
the feathera of the peacock's tail. 

" Butterflies, motbs, and many other Insects, 
covered with scales or feathers, overlapping 
other like the tiles of a house. They Tory 
io form and size, and from the difficulty with^ 
the structure of many of them is developed by 
microscope, they .become excellent tests uf il* 
trsting power. In tbe list, 1 have introduced 
most intere^ting^nd peculiar, and it may be ofe 
that such are seldom foood on the rrif parts 
wing ; the white or blue yield the greatest 

" If the cryaUlline lens in tbe eye of a fisfcT 
minutely examined by the aid of the micro»co|ii, 
it will be found Io be composed of a number o(i 
centric strata or layers, somewhat 
coats of an onion. One of these UuioB,{ 
and placed under a powerful microKope. wHl fet 
seen to consist of flat fibres or bands, arising fres» 
each pole of the globular lens, and expi 
towards the equator, like the spaces beCwi 
meridians on the artificial globe. The edge* of 
f\brea arc serrated, and fit into each other like ths 
teeth of a-^Buble rack, or the sutures of the hunua 
skull. Sir David Brewster, who first mtnatfly 
examined tbe structure of these lensea, has 
rately measured the width of the bands^ 
Pfiii. 7Va«, 1833.) He found a single leni. 
tenths of an inch in diameter, from the rye of < 
contained five millions of these flat fibred 
62,&t>0 millions of sorratnres or teeth. Wl 
as opaque or as transparent objects, ] hate baa 
much delighted with then. Viewf»l «= th. I'lnn^, 
an amplificattm of 250 timrs is v fa* 

tbe latter, 400 times linear may be ; : «stb 

advantage. 

** The method of mounting in alcohol or spirit of { 
wine is as follows : — Take a slip of glass, and envn 
it on one side with a coat of painters' whitcioad. 
leaving a space in the middle large enough to i 
tbe object to be mounted -, — when this coat i»i 
add another, and proceed thus until a 
thickness is obtained lor tbe inclosure of the ob| 
to be mounted. The next thing is to procure a desr] 
piece of mica, free from veins and flaws, anj ratlisr 
smaller than the slip of glass. Fill the caviijr obevs 
referred to with spirit of wine, pUoe the objvet 
therein, and cover it with a plate of mica, whiib 
must be brought into dose cont«ct with the wkUi* 
lead, by gently pressing it with a smooth pilsf ofj 
wood from oneextrcmity totheother, so MptfriMyr 
to expel the air-bubbles. In a few days the wbit»> 
Uadk If ill have became hard, and if the mica b« wund. 



MAGAZINE OF SCIENCE. 



403 



•pecimfra miij be preferred for yt»n. 
it must be remembered that uceptinif 
•meaUry dimes, much of their delicacy is 
td hj this method of moantiag, althuugh in 
n it is sull btf^tily desirable. 
most iaterefting actire phenomentm ex- 
'by tbe mirruscope is Che cirnulsttoa of the 
flurdtt in 101011113 and plnnls. Tn the 
(he globales of blood may be teen patHinr 
^Ong tbe esptlUry ends of the arterira into 
P the reiot, when the iuterrening membrane 
M\y dittphanniiR, is io tbe ear of the youn^ 
thfl Atib and tail of th« carp, gold-fioh, 
*rk. tadpole, and of raoit small tish ; and 
»eb betwecu the toes of the frog, liziird, eft, 
or these purposes, a magnifying poner from 
S50 times linear is sutficieut. 
th€ Arachnoids (Spider tribe,) at the joints 
Ngs, I htve obnervL'd tbe rirrulatioQ TCfy 
b the enrreat of dark globules passing rapidly 
pulsation of the dors&l Teasel. In the 
and wings of terrestrial insects, it has also 
D when tliey hara jnat emerged from the 
, as in Ihc Pcria viridis and Semblis lilineata. 
Irsl aquatic lanrR and amall cruktacea, the 
Ing fluid traverses tbe limbs, antennir, and 
(bence moves along thexlfersal ressel towards 
\f and doim the sides of the body, in cavities, 
iKatinet Teasels ; hence called dijfvsed cir- 
The moit favorable subjects for viewing 
the following : — Larva of tbe ephemem. 
ie*nt diacovery of the beautifnl mcchaniam 
rial vessel of this larva by Mr. Howerbank 
oonflrmed by the ^arcful dissections of 
port, who, with much perseverance, hu erf- 
Ibese inquiries to the other states of insects.) 
■ hydraphilus ; t maU dyttscoa ; agnon pnella. 
riegant Urt« I have not observed the clr- 
in the Irgs to extend beyond the haunches.) 
round lyncens; frcsh-wat«r shrimp; 
(Oniscns) ; Ligia ; water flea (daphiiia 
dec. Power 100 to 30O timi 



indiriss, ■ertulsha*, campanulartae, pln- 
&c. Mr. Lister has, by means of the 
ic engiscope, discovered a circulation to 
ich in many respects resembles that in 
~ PMU. Trans, 

tation in plants termed eyetotis ia ■ 
•f the fluid contained in each cellule, 
linct from those surrounding it. It can 
ed in all plants in which tbe circulating 
aloa particles of a different refractive 
intensity, and the cellules of sufficient siso 
pveocy. Hence all lactescent ptauts. or 
l»inga milky juice, with the other conditions, 
*this pbennmi'oon. The following aqaatio 
! geneiallj transparent enough to show the 
n in every part of them :— Nit«lla byalina ; 
inalucens ; chara Tulgaris ; and caulinia 
In the frog. hit (hydrorhnris) it is best 
le stipuJae of the leaves and the ends of the 
The magnifying power suited for the above 
een 100 aud 250 times linear. In the 
»rt (tradescantia vtrginica) it is seen ia the 
•urrounding the stamcnf of the flower : 
00 to SOO times linear. In tbe common 
(ienecto vnlgnriii) it ia said to be seen in 
sarrounding thr. stalks and flowers. In 
eria spiralis circulation m^iy be seen in 
" I«af.»» 



ETCHING AND DYEING FIGURES ON 
IVORY. , 

BV /. CATRERT. 

Thb osoal mode of ornamenting ivory in black is to 
engrave tbe pattern or design, and then to 611 up 
the cmvities thus produced with bard bUck Tsmisb. 
The demand for engraved ivory in ornamental in- 
tayiog, and fur other parposes, is considerable, al- 
though the price paid for it is not such as to encou- 
rage artists of much ability to devote themsf Ires to 
this work, which consequently is trivial in desipi 
and coarse in ezecutiou. Mr. Calhery's ituprove- 
ment consists in coveriug tbe irory with engrAvei'a 
varnish, and drawing the design with an etching 
needle ; he then pours on a mruslruum conipusocl 
of one hundred aud twenty grains of fine silver, 
dissolved in one ounce measare of nitrii: add, and 
then diluted with one quart of pure distilled water. 
After half an hour, more or less, according to the 
required depth of tint, tbe liquor is to be poured off. 
and the surface is to be washed vrith diitilled water, 
and dried with blotuug paper ; it ia then to be es> 
poied to the light for an hour, after which the varnish 
may be removed by means of oil of turpentine. 
Tbe design will now appear permanently iuipressed 
ou the ivory, and of a black or hlackish brown color, 
which will come to its full tint after exposure for i 
day or two to the light. 

The property which nitrate of silver possuses, of 
giving a ptrmanent dark ataia lo, ivory and many 
other Hubstancrs has been long known ; but Mr. 
Cathery has tbe merit of having advantageously 
applied it in a departmenlof art in which it is likely 
to be of consit^rable service, by improving the 
quality of the ornament, and at the same time of 
dimtaishing the cost. Varieties of color may also 
be given by substituting the salts of gold, phitiua, 
co^P^^'AC^ for the ^otukion o/*. silver. * 

EARTUQUAKKS. 



«« .. A.v««,^hqunke consists of a violent agitation of the 

T«ral of the polypiferous zb7>f(ly!kJ8^£XfBe^N^"V^f*^^"™P'''*i*='l W varioas other phenomcua 




. I 



more or less singular and destructive in their efl'ecta, 
but by no means uniform in character, as the fol- 
lowing enumerHtion of cuncomitnnt circumstNOCes, 
gleaned from tbe accounts of various enrthquakat 
tbitt have occurred in ancient and modern times, 
will sufficiently evince. F.urthquskes are usually 
preceded by a general stillness in the utr, and an 
unnataral agitation of the waters of the ocean and 
of lakes. The shock comes on with a deep rumbhng 
noise. Like that of a carriage over a rough pavement, 
or with a tremendous exploaion reseutbiiug a dia. 
charge of artiUery. or the bursting of a thunder 
cloud ; and aometimea heaves the ground perpeodi- 
cularly upwards, and sometimes rolls it from side to 
aide. The single shocks of an earthquake scldon 
last longer than a minute, but they frequttuly follow 
one another at short intervals for a considerable 
length of time. During these shocks large chasms 
are made in the ground, from which auinetimca 
smoke and flames, hut more frequently stones and 
torrenU ot water, are discharged. In violent earth- 
quakes, these chasms are sometimeji so extensive as 
to overwhelm whole cities at once. In consequence 
of these shocks, also, whole ialau^s are frequently 
sank and new onea raised ; the course of nvera is 
changed; seaa overflow the laod, forming gulfs, 
hays, and straits ; sometime* disrupting the land 
into islsndi, and ■ometuun joining them to U* 
coulmcnt. 



404 



MAGA2JNE OF SCIENCE. 



"niere U uo portioa of the earth's surfBoe, whe- 
ther it be Und or water, that is not more or ItM 
inbjcct to ckrlhqaakn ; and records of ihdr de- 
■tructiYe efTcctB Iihvc been tranimilted lo uk through 
CTerjr a^. The first earlhqaake particnlarlj worthy 
of notice was that which, in a.d. 63, deitroycd 
Uercalancum and Pompeii. In the fourth and fifth 
centuricj, some of the most civilized parts of the 
world were almost deiolated bj these awful riiita- 
lionn. Thrace, Syria, and Airift Minor, according 
to contemporary historiani, suJTered roost Bererely. 
On the 2rith of January, a.d. -W7, subterranean 
thunders werti beard from the Black to the Rnl Sra, 
And the earth was convulsed, without intcmiisftion. 
for the ipice of slz months ; and in Phrygiu, many 
citifs and Urge tracts of ground were swallowed up. 
On the 30th of May, a.d. 205, the city of Aatioch 
was OTerwhelmed by a dreadful earthquake, and 
260,000 of its inhabitants are said to have been 
crushed in its rains. 

In the year 1340, Asia Minor and £^pt were 
Tiotently shaken ; and in the following year serere 
earthquakes were experienced in Cypras, Greece, 
and Italy. 

In 1692, the island of Jamaica wu visited by a 
terrible earthquake, in which enormous masses of 
earth were detiiched from the Blue Mountains ; and 
Tast quantities of timber, hurled from their flanks, 
corered the adjacent sea, like floating inlands. Jt 
was daring this earthquake that the city of Port 
Royal, with a large tract of adjacent laiid, sunk 
instantaneously into the sea. In the following year 
great earthquakes occurred in Sicily, which destroyed 
Catania aod 140 other towns and villages, with 
100,000 of their inhabitants. 

Since the records of history, there have been no 
eartbqunkcs equal in intensity to thoMwhich ravaged 
diOcrent parts of the world in the eighteenth cen* 
tury. Passing over the convulsion which in 1746 
nearly laid waste Lower Pern, and those by which 
in 1750 the ancient town of Concepcion in Chili 
was totally destroyed, we corae to 1755, when the 
city of Lisbon was almost wholly destroyed by one 
of the most destructive earthquakes which ever 
occurred in Eorope. It continued only six minutes ; 
but such was the violence of the convulsion, that in 
Uist short space upwards of 60.000 persons are said 
to have perished. The phenomena that accoo- 
paaied it were no less striking. The sea first retired 
and laid tlie bar dry ; it then rolled m, rising fifty 
ft_>et ur more above itn ordinary level. The largest 
mountains in Portugal were impetuously shaken 
from their very fuundatiuDS ; and -some of them 
opened at their summits, which were split and rent 
in a wonderful manner, huge masses of them being 
thrown down into the subjitcent valleys. But (he 
most remarkable circumstance which occurred at 
Lisbon during this oatjistrophe was the entire sob- 
sidmco of tlie new quay, cnlleil Cays de Prsdn, to 
which an immense concourse of people had tied for 
safety from the falling ruins. Prom (his hideous 
abyss, into which tha quay sunk, not one of the 
dead bodies ever floated to tlio surface ; and on the 
spot there is now water Co the depth of 100 fathoms. 
This earthquake excited great attention from the 
incredibly great extent at which contemporary shocks 
were experienced. The violence of the shocks, 
which were accompanied by a terrific sabterranean 
noise, like the loud«<t thunder, wns chJeHy felt in 
Portugal, Spain, and nortlicm Africa; but the 
vffects of the earth({uake wer« percoived in slmoHt 
aU the countries of cQnliueulal Luiopc, aad were 




even ex|>erienoed in tlw Went Indies, aod cm lla 
Lake Ontario in North America. 8hipa at tea «o« 
affected by the shocks as if tbey had strwk so 
rocks ; and even at some of the Nctittish takes, Lseb 
Lomond in particular, the wauir, without tha Inal 
apparent cause, rose to the perpendicular faeig^af 
two feet four inches against its baolu, and thsa 
subsided below iu usual level. During tLe tax 
twenty years, various emrtfaquskes uci'urred in dif- 
ferent parts of the world, attended vni'di mors or 
leas destructive consequences. Iu 17:^0, Syria vu 
agitated by violent earthquakes, the sU<H:ka of whkh 
were protracted for three mouths, tbrr)ughauia*|iac« 
of 10,000 square leagoes, and levelled to the KToaad 
Aocon, SaphaC, Ualbeck, Damascus, Sidon, Tripok) 
and many other placea. la each of tbeae 
many thoxuands of the inhabitants perished 
in the valtuy of Ealbeck alone, ZO,OUU m 
to have been victims to tlic convnUlon. 
the island of Trinidad and great part of C 
were riolently agitated by earthquake*. 1 
the lofty volcano of Papandaysng, the 
monntain iu Java, disappeared, and a cm 
area, fifteen miles by six, was swallow i 
1783, the oorth-eostern part of Sicily son 
southern portioa of Calabria were coDTttlsed 
violent and oft-repeated shocks, which ot 
the town of Messina, and killed many tbonaaoda 
its inhabitants, as well aa many prraons in 
In the some year the islands of Japut, 1 
178G. Sicily and the Coraccas in 1790, Q 
17<J], and the Antilles and Peru in 1797, 
violently agitated by convulsions of this ktiul. 

Since the commuocement of the present centttrx* 
various eartltquakea have occurred boih in iheOU 
and New ^VurId. In 18U* Tiolcikt rortbquaka 
shook the valley uf the Mississippi, by which lakts 
of considerable extent disappeared, and new 
were formed, In 1812, Coraccas vras i 
and upwards of 12,000 of its inlubitanta 
the ruins. In 1815 the town of Tombora, la 
island of Sumbawo, was completely deotroyed hy 
an earthquake, which extended throughout an ars* 
100 miles in diameter, and destroyed 12.OU0 per* 
sons. In 1819, a violent earthquake oocorrcd Ol 
Cutch, in the Delta of the Indus, by whir-h, aoMBi 
other disastrous consequences, the principol town. 
Bhoog, was converted into a heap of i 
1B22, Aleppo was destroyed by an earth<, 
the same year Chili was visited by a moat o^sinAutn 
earthquake, from which the coast for lOUmilssll 
stated to have sostained an elevation of fron t«v 
to four feet, while about a mite inland from VsW 
poraiso, it was raised from six to aeveri focL la 
1827, Popsyon snd Bogota saflcred scvcnrly fms 
earthquakes, during which vast fissures opened is 
the elevated plains around the latter city. In liU, 
the town of Concepcion, in Chili, was entirely d»< 
moliabed by an eartht|uake. In 1837, the oountfiM 
along the eastern exircmity of the MediterriMM* 
especially Syria, were violently agitated by aa eafli* 
qaake, which caused great daiungc to the towns of 
Damascus, AcrCi Tyre, and Sidon, and rnUftly 
destroyed Tiberias and Ssfet. Such are mm» <! 
the most violent earthquakes that have ooeuiHt 
within the period uf authentic history. T}u raadei 
will tind in Po^yfrnhrf^* Annaim bsta of tlx' dif- 
ferent earthquakes tliat havf> taken plaoe withia tils 
last twenty years ; and from these It niU beebsoVHl 
that scarcely a month ulapM-s withuut bang ^* 
nalixed by one or many cnnvutnons in aomf part of 
the globe* Shocki o( earthquakes b4ie at ctiffasoi 



^mk 



MAGAZINK OK SCIENCE. 



405 



b0n felt in Tkrioui parUofBrituo, ftndmore 
\y in Scotland ; but they hare all fortu- 
been to Inst^ificant, compared to thote 
IWTe been uperieaced la other couutrics, 
shall refrain from entering into any detaila 
ig Uicoi. 

tbouglt history auppUes us with ao large a 
of well -authenticated carthquake«f it ia 
that so little waa dono by the ancienti 
irestigating their causea or noticiDg tbeir 
It ifl only H-iihin the taat century and a 
lyB Mr. Ljell, since Hooks fint promulgated 
^uig the connection between geolo- 
a and earthqaakei, that the per- 
tgea effected by theae coovubloua have 
tion. Before that time the narratiTC 
Ian waa almoai excloaively coafined to 
of hamao being« who pcriahed, the 
of cities laid in ruina, the value of property 
>yed, Of ci>-rCain atmospheric apj>earaocea which 
d or terrified the obaervera. The creation of 
lake, the engulphing of a city, or the raising 
ew Ltland, are aomeiiniea, it ia true, adverted 
baing too obvious or of too much geographical 
It to be [Muaed over in sUcDce. But do re* 
were made expreaaly with the Tiew of 
ting the amount of depression or elevation 
ground, or any particular alterations in the 
pottiioD of sea and laud ; and very little 
waa made between the raising of soil by 
ejections, and the upheaving of it by forces 
below. The same remark, applies to a very 
proportion of modem accounts ; and how much 
wfl hnve to regret this deficiency of informa- 
>eara from this, that in every instance where 
of scientific inquiry has animntcd the cye- 
of these events, facts calculated tu throw 
former modificationa of the earth's itructare 
led. 

'"MAKING OF DISTILLED WATERS. 

( Hf tuned from page 4U0. ami c<mclu<iedj 

Viakt nuemary water. — Ai the method of 

ling the operation by the cold atilt ia the 

LUC. whatever plant or flower is used, the 

ing initanco of procuring a water from roie- 

wilt be abundantly sufficient to instmot the 

practitioner in the manner of conducting the 

1 in all casea whatever. Take rosemary, fresh 

ired in its perfection, with the morning dew 

it, and lay it lightly and uobruised upon the 

r bottom of the still ; cover the pUte with its 

bead, and apply a glasa receiver to the nose 

Mske a mail fire of charcoal under the 

eontinning it aa long aa any liquor comes over 

the receiver. When nothing more cornea over, 

off the still head, and reroirve the plant, putting 

in ita stead, and proceed aa before; continue 

It the operation successively, till a 6uAioient 

of water ia procured. Let this distilied 

! kept at rest in cleun bottle«, close stufped, 

9 days in a cold place ; by this means it will 

Umpid, and powerfully impregnated with 

mad amell of the plant. 

7lf pemtyroyai water. — Take of pennyroyal 

dry, a pound and a half ; water as much aa 

rent burning. Drawing off by distillation 

H continu'.'s. 

tfteartumt prater. — Take of spearmint 

£rtkh, any quantity ; water, three times aa 

UtsUi «i long as the liquor which comes 



OTM* hw ■ Gonaiderabie laste or smell of the miut. 
Or, take spearmint leaves, dried. 1^ lbs., water, as 
much as ia sufficient to pretent burning. Draw off 
by diatillatton I gallon. 

Cinnamon roier.— Take of braised cinnnmon, I 
lb., water. 2 gallons. Simmer in s sdU for hall an 
hour, put what oomes over into the atiil again ; 
when cold, strain through flannel. 

JSttU •ant'pareil. — Take two gallona of fine old 
boBey*water, put it into a still capable of holdiog^ 
foar gallons, and aJd the thinly pared rindi of six 
or eight freah citrons, neither yrttn nor mfilnv ripe. 
Then add siity or seventy drops of fine Roman 
bergamot ; and, baring luted the apparaCua well, let 
the whole digest in a moderate heat for twenty-four 
hours. Draw off, by a water-bath heat, about one 
gallon. 

JMtmmiiu watfr. — Take six pounds of the white 
sweet almond cokes, from which jessamine oil haa 
been made abroad; beat and sifl them to a fine 
powder, and put to it aa much fresh oil of jeaanmiiM 
aa will be required to make it into a stiff paste. 
Let this paatc be dissolved in about six quart* of 
spring water, which has been previously well boiled, 
and left until it has become about half cold. Stir 
and mix the whole well together ; and when the oil 
and water has , been well combined, let the whole 
stand until the powder has fallen to the bottom of 
the veasol. Now pour the liquid off gently, and 
filter it through cotton, in a large tin funnel, into 
the glass bottle in which it is to be kept for uat. 
The powder or sediment which baa been left at the 
bottom of the veasel, when dried by the heat ot' the 
sun, answen very well for making sJaumd-paate for 
the hands. 

Myrtle water. — Infuse eight or ten lbs. of the 
cuttings of green myrtle, iu nearly twenty gallona 
of rain or river water, and add thereto a pint of 
fresh yeast, after it has stood for twenty-four boon. 
At the end of another day snd night, put the whole 
into a Btill. with a pound of bay salt. Draw off the 
whole of the water ; and, next day, tofose more 
myrtle leaToa, as before, and distil again. Repent 
the iama • tfakrd time. 

Orange Jkmrer water. — Take two lbs. of orange 
Bowers, and twenty-four qnarta of water, and draw 
over three pints. Or, take twelve lbs. of orange 
flowers, and sixteen quarta of water, end draw over 
fifteen quarts. 

Orange pert wafer.-^Take of the outward yellow 
rind of Seville oranges, four oonoea ; water, three 
gallons and a half; draw off one gallon by the still, 
with a briak fire. 

Peppermini water. — Take of the herb of pepper- 
mint, drisd, l^ lbs., and of water, aa much as is 
sufficient to 'prevent boming : distil off a gallon. 
This has been known to allay sickness when nothii^ 
else would sucaeed, and is used in flatulent colics. 
A wine-glassful may be taken, and often repeated. 

Another. Take of oil of peppermint, one Lb., 
water a suiCcient quantity. . Draw off thirty gallons. 
This is stimulant and carminative ; and covers dis- 
agreeable AaTora. 

Portttgal tmd angel waters. — Take ""a pint of 
orange-flower water, a pint of roae-water, and half 
a pint of myrtle-water; to these put a quarter of 
an ounce of distilled spirit of musk, and an ounoB 
of spirit of srabergris. Shake tbe whole well to- 
gether, and the prooees will be finished. 

iiote water. — Take of the leaves of &esh damaak 
roaea with the heels cut off, six lbs., water, u anub 
as to prevent borniog. Distil off s gallon. 



MAGAZINE OF SCIENCE. 



: 



To matt any distilled walert. — Aa all distilled 
wtten consift ooerely of «at«r imprpgnat«d with the 
esieDtinl oil of herbs, thej may be promptly made 
by purcbuiug the eavenU'al oil at auy chenaiita. 

Thrn triturate oil in a mortar, aay \ an oz., with 
a \ lb. of Eugar, or some mognetia, and minKleTrith 
water to your fancy. The distilled n'sterv nhoald be 
drawn from dried herbi, because the freeh cannot 
be got It all times in the year. M>''heneTrr the frenh 
areu»ed the weight* must be increased; but whether 
the freah or dry are mode ase of, it is left to the 
jadgment of the operator to vary the weight, accord- 
iDg aa the plants are in greater or leaa perfection* 
owlBg to the season in which they gr«w, or were 
coUected. 



TO MANUFACTURE REAL . MOROCCO 

LEATHER, 
The akins being first dried in the air* ftre steeped 
in water three days and nights; tlien stretched on 
II tanner's bone, beateu with a large knife, and 
steeped afresh in water every day : they are then 
thrown into a targe vst on the groand, full of water, 
where qaicklime has been slacked, and there he 
fifteen days; whence they arc token, and again 
returned every night and morning. They are uext 
thrown into a fresh vat of lime and water, and 
shifted night and morning for fifteen days longer ; 
then rinsed in clean water, and the hair taken off 
on the leg with the knife, returned into a third vat, 
and shifted as before for eighteen days ; ateeped 
twelve hours in a river, taken out, rinsed, pm in 
pails, where they are pounded with wooden pestles. 
changing the water twice; then laid ud the horse, 
and Ibe flesh Ukcn off; returned into pails of new 
water, taken out, and the hair-side scraped; returned 
into fresh pails, taken out, and thrown into a pail 
of a particulor form, having holes at bottom : here 
they arc beaten for the space of an hour, and fresh 
water poured on from time to time; then being 
stretched on the leg, and scraped on either side, 
they arc returned into paiU of freeh water, taken 
out, atretched, and sewed up all round, in the 
manner of bags, leaving out (he hinder legs, as an 
aperture for the conveyance of a oaiitare described 
below. 

The skins thns sewed are put in loke-warra water, 
where dogs* excrcnienta have been dltiaolved. Here 
they are stirred with long polt-a for half an boor, 
left at rest for twelve hoars, uken out, rinsed in 
Cresh water, and filled by a funnel with a prepara- 
tion of water and sumach , mixed and heated over 
the fire till ready to boil ; and, aa they are filled, 
the hind legs are sewed ap to siO)> the passage. In 
this state they are let down into the vessel of water 
and sumach, and kept stirring for four hours anc- 
ccasively ; taken out and heaped on one another : 
after a little time their aides ore changed, and thus 
they continue an hour and a half till drained. This 
done, they are loosened, and filled a second time 
with the same preparation, sewed up again, and kept 
atirring two hours, piled up and drained oii before. 
The process is again repeated with this difTerence, 
that they are then only atirned a quarter of an hour; 
after which they are left till next morning, when 
ttiey are taken oat, drained on a rack, unsewed, the 
aumach taken out, folded in two from brad to tail, 
the hair-aidfl outwards, Inid over each other on the 
leg, to perfect their draining, atretched out and 
dried : then trampled under foot by two and two, 
stretched on a wooden table, what Hesh and sitniocb 



remRins scraped olf, the hair-side rubbed ovar vilh 
oil, and that again with water. 

They are then rung with the hands, stretched, 
and pressed tight on the table with an iron instn- 
ment like that of a currier, the flesh-side upper- 
most; then turned, and the hair-tide rubbod atroQ^ 
over with a handful of nubea, to squeeze OQt 
much of the oil remsinlng u possible. The 
coat of black is now Ivid on X\x balr-iide, by 
of a lock of hair twisted and steeped in a kind 
black dye, prepared of sour beer, wherein pieect 
old rusty iron have been thrown. When b«lf-dri*4 
in the air, they are stretched on a table, rvbbed ow 
every way with a paumelle, or wooden -tootlied in* 
■trument, to raise the grain, over which is pasaad a 
light coucbe of water, then sleeked by rubbing 
with rashes prepared for the purpose. Thus si 
they have a second coache of black, then dried, 
on the table, rubbed over with a paumelle of 
to raise the grain again ; and, after a light coi 
of water, sleeked over anew ; and to raise the gr^ 
a third time, a paumelle of wood is used. 

After the hair-side has received all its prepsrv 
tions, the flesh side is pared with a sharp knife for 
the purpose ; the hair-side is strongly tubbed ovtt 
with a woollen rap, having licforc given it a gloiS 
with barberries, citron, or orange. The whole k 
finished by raising the grain lightly, or the Isit Uma, 
with the panmclle of cork ; so that they are now fit 
for the market. 

7\} prepare Red Aforoceo. — After *te<et>infr 
atrr-lrhing, scraping, besting, and rinsing the axlns, 
aa before, they are st length wrung, stretched oa 
the leg. snd passed after each other into water wharf 
alum has been dissolved. Thus olumed, they ars 
left to drain till morning, then wmng out, puOcd 
on the leg, and folded from head to tail, the ficsh 
inwards. 

In this state they receive their first dye. by paninc 
them after one another into a red liquor, deacribM 
hereafter. Thia is repealed again and again, tlU 
the ckius have got their first color ; then they •»* 
rinsed in clean water, stretched on the leg. and iHt 
to drain twelve hours ; thrown into water throNgh 
a sieve, and stirred incessantly for a day with laog 
poles ; taken oat. hung on a bar across the wattr 
all night, white against red, and red againct white, 
and in the morning the water stirred up, and thi 
skins returned into it for twenty-four hour*. 

Inyredienh for the Bed Color. — The following if 
the quantity and proportions of the iiigrrOimta 
required for the red color, for a parcel of thirty -ais 
skins: — Cochineal, 130 drachms; round sucbrt, 
(croeits indicut^ 45 drachms ; gutta gsmba, lA 
drachms ; white alum pulvenaed, 10 drachma ; bark 
of the pomegranate tree, 10 drachms ; citron juioa, 
2 drachms ; and common water. 120 ponods. Hm 
alum is gradually added to the other aiticlea. and 
boiled in a copper for about two hoora, till oa^ 
tenth part of the water be consumed. 



FULMINATING COMPOUNDS. 

f&eivmedfnm page 392, a\ii ametmkd j 
PoDR 2 drams of sulphuric acid into a gallipot, 
throw into it 4 groins of chlorate of potoas, 
grain of phosphorus, divided into minute pai 
Here, in addition to Ibe explosion, a very ' 
inflaiumation will take place. In this, luid the 
following experiments, the cotnbustihlf motansla 
should be gently mixed with a wmidea «krwrr in iW 
spoon, from which they are to be thrown uito the aciiL. 



MAGAZINE OF SCIENCE. 



407 




Tfarov. Irom the point of ■ kniie, three or foar 
gnhii of chlorite uf lUver on red-hot chorcool ; 
OrfUfrtttiori will be the coaseqaence, and the ulfer 
will he retlut'fcd to i metallic itate on the charcoal. 

I'l • I" '> 111 anvU 2 grains of chlorate of potau 

I pulverised areeoic, and strike them 

< polished hammer; h very luud ez< 

uUcnded hj a floAb of light, will be the 

. :ice. Here the iot^nsitf of beat caiues 

tultuu of the metal. 

1 only a small qoauiitj of this powder should 
■c ODc time, the conititncnts ibould be 
arate phials, and mixed ai occasion may 
Mix together 5 drama of the chlorate of 
i drama of pulverised arsenic (the metal) 
on paper, with a quill or pointed Htick, 
rr it with a very loog mitch ; a very vivid and 
iaddeo combustion will take place. If couficied, 
the oombostion will be attended by a loud report. 
la thU eompoand, the arsenic is the principal 
^abuatible. 

Mix gently in a tea-spoon 3 grains of chlorate of 
poUts and 3 griioKof puWenaed arsenic (the metal): 
throw tbe mixture into a gnllipot containing 2 drama 
of sulphuric add; instant dedagration will take plaoe. 
Prepare a solotioo of nitrate of ammonia in a very 
clean jar, so that about nne half shull be filled : let 
tfaii solution be of the temperature of 4^' Fahr. 
Now pass into the jar aome chlorine gas from a 
rvlort containing 1 ounce of oxide of maaganeae 
•■d 2 ounces of muriatic acid. The gas will be 
ahoorbcd almost ns rapidly as it ascends, and pre- 
sently the top of the solution will be covered by a 
ftlm, which collecting into yellow globules, will fall 
to the bottom. This is the chloride of azote, the 
aaost explosive body with which wo are acquainted ; 
it is indeed so mucb so, that great danger is to be 
apprehended from the employment of more tlian a 
globule of tha sixe of a pin'i head, in the perform- 
ance uf experiments. This substance should never 
be touched by any thing which has the least particle 
of grease or oil on it (except for experiment) as it 
C3tplodes in an instant, and may do much mischief; 
—several eminent chemists have been leriousty 
irosnded by it- It is beat not to make more at oud 
time than is wanted for present experiment. 

Put a particle of chloride of aiote, of the size of 
a pin's head, into an iron-spoon tied, to tbe end of 
• Uog-sticlf ; hold the spoon over a lamp or fire for 
A fbw seounds ; the chloride will explode with a very 
Ipod report. 

Pdl half a grain of chloride of azote into a very 

^ripn small delft basin, and pour upon it (from a 

^^^BOn tied to the end of a long stick) a few drops 

VToIive, almond, or any essential oil. The instant 

like oil Mil, a tremenduuB explosion wiU take place: 

tii« basin will be shattered into pieces. 

If half a grain of chloride of azote be put gently 
oa half a Sheet of clean writiug>paper, and a grain 
of phoaphoruB (stuck on tho sharpened end of a 
wire, about a yard long) be brouf^ht into contact 
with it, a most violent explosion will instantly take 
place. This experiment has been performed in a 
•oup-plate; and ths quantities used were I gtain of 
each anbstnnre. The explosion was so violent as to 
shatter tho plate into a thousand pieces. It is very 
dangerous to use more than the quantities here 
Bentioned ; and 'particularly to, if the vessel ,in 
which the experiment is performed be dirty or 
greasy. It is proper to put the hand before the 
cye« whilst this explosion tukes plaoe, to prevent 
Qie pboiphonu from entdriug them. 



If 6 grtiiu of charcoal, in powder, be gently 
mixed with 6 grains of lodate of potass, and laid 
(folded in a small piece of paper) on an anvil ; a 
smart blow from a bummer, will cause a bud 
detoaation. 

Into distilled water fully saturated wlUi ommo- 
oiacal ^as, put some iodine, as lun^ as a dark pow- 
der falls down: pour oiT the liquor gently — (this 
liquor is a solution of hydriodic acid, and may be 
preserved for experiment) — and preserve the pow. 
der : this powder ii the iodide of oxote ; the other 
portion of the iodine having combined with tha 
hydrogen of the ammonia forming hydriodic acid. 
This powder will detonate by the least heat or 
friction. 

Agitate some liquid cfaloriodio acid in a phial 
containing chlorine gas : as the absorption prooeedc, 
tbe liquid will be rendered colorieas. If this color- 
less liquid be poured into pure liquid ammonia, a 
white powder will be precipitated, which detonates 
by the gentlest beat or friction. 

Put 10 grains of pure silver into a Florence Bosk, 
and pour over it half an ounce of nitric acid, with 
half an ounce of distilled water; when nearly dis- 
solved, put it over a lamp, and then pour in half aa 
ounce of alcohol ; when it has received considerable 
heat, a white heavy powder will fnW to the bottom. 
When this precipitation ceases, agitate the whole 
gently, and pour it on a filter; wash out any re- 
siduum with warm water ; and potir this also on tha 
filter ; continue to pour distilled water over the 
powder until it runs through quite tasteless. Now 
dry the powder in a watch-glo^s or wlde-nonthed 
phial by a gentle heat ; and when any is wanted for 
experiment, take it out with a Rmnll wooden spatnla. 

Wrap a groin of detonating silver in a small piece 
of paf»er, place it on tbe flour, and press upon it 
with the heel ; a brisk explosion, with slight in- 
flammation, will be tbe consequence. The same 
wil! take place when thtssubataiicr is struck upon an 
anvil. This compound has been made the labjeot 
of many amusing experiments, by inclosing small 
quantities of it in glass beads, &c., and pasting 
paper over them ; they are then called detonating 
balls, l^ere are also detonating spiders, detonating 
letters, fee. 

Throw 2 grains of detonating silver into a galli- 
pot, containing 1 dram of nitric arid ; explosion 
and inflammation will take place, and the acid will 
bo thrown about. 

Prepare a solution of nitrate of silver, and pour 
into it a solution of pnre Hme in water, as long as 
a precipitate will fall down. Filter the liquid, and 
wash the precipitate by pouring warm water on it, 
as it stands on the Alter. Now put the powder into 
a warm place upon the paper, that it may be nell 
dried ; then put it into a wide-moathed phial, oon- 
tainitig pure liquid ammonia— cork it, and let it 
remain undisturbed for a whole day, or until the 
powder becomes black. Now pour off the super- 
natant liepior, and put the phial, open, in a place 
whrre tbe heat moy not be more than 80° or 100^. 
When dry, this powder is very explosive, and should 
remnin undisturbed in the phial where the process 
was finished ; as sometimes, the least friction will 
cause an explosion of the whole mass. The lid of a 
pill-box is the best cover the phinl can bavr» ss 
frequently, in taking the powder out, a part adheres 
to the neck ; and then, if a stopper or cork be put 
in, the friction occasioned even by this ia sometimes 
sufficient to explode the whole. Perhaps, if all 
fulminating powden wer« dried ia walcfa- glasses, 



MAGAZINB OF SCIKNCE. 



kdJ pemianl to reinaiu io them till wanlal for (Ue, 1 
i( vouM be Diuch tafer. 

Put 50 grains of mercury into ■ retort, and pour 
over it 6 druas of stroni; nitric acfd ; place the re- 
tort over a lamp nntil thu metal ii diisolved. Now 
poor an oance of alroliol into a Florence flask, and 
when the nitrate ii cold, pour it \n also. Place the 
lUak on the ring, at a considerable distance aboTc 
the flame of the lamp, w aa not to heat it too much 
■t ftnt : efferrcBcence will toon commence, and a 
powder will he precipitated immediately. When 
the whole of the precipitate haa fallen down, pour 
the contenta of the flask on a Alter, wash out the 
precipitate with water, and pour thii also on the 
filter. When the liqaor lias passed throajth, pour 
dialillad water over the powder, in order thai it may 
be totally freed from the acid : this will be known 
by the water paasing through qnitc tastelefis. Col- 
lect the powder oo a watch-glasa, and dry it in a 
plaos. the teropemture of which doca not exceed 10(r . 
Thia fulminating powder will weigh about a dram, 
and rosy bo preienred either ia » watoh-flast, or in 
a wide-mouthed phial. 

GALVANIC REVERSER. 

r Tit An Editor. J 
Sir.— I send you a description of a galvmnic re- 
verter, which ia both cheap and cffntiTe. The 
Inserttoo will oblige a. nicholm>n. 

A, piece of mahogany of any shape. harLoc « 
turned grooTe, ( of an inoh deep and wide, to hold 
■er«ury, and dinded in n line with the centre, by 
two pieces of ivory or bon« E E, to half the height 
of groove. F, piece of mahogany haring a mercary 
cop, terminating in a point at each end; a itout 
wire fixed in the centre, fitting the hole C, and of 
a length just anfticicnt to allow thf points to dip in 
the mercury, E E, hole§ oommunicatiBg with the 
mercury groove to connect «p[Muatus. 

AH tlial is necessary to aet the inatmment to 
work, ia to adjust the piece F. ao that the poinU 
will just pass orer £ E ; put mercnry in tha onps. 
and in the groove high enough for the points to dip 
in it ; connect the apparatus by wim, inserted in 
E E, and the battery by placing the poles in the 
mercury cup». A alight move of the piece F will 
now give the eaatem or western rotation. 




It b not necemry that the canal for the mercury 
should be much longer at each end than the dotted 
line, hut I prefer iU going all roond for the more 
(onvanlent removal of the mercury. 



MEMORANDA. 

Preiterpation of Fi-nitt by Carbonic Acul.- 



-TW 



details of soma very interesting expcrimfnta wfll W 
found in the Ann. de Chim. ft tie Phy». (Jan. liJlSl. 
tending to prove that fraiti may be preaerred kf 
means of carbonic acid gsa. Cherries, grapes, pean« 
apples, and chesnuts. were pisced in glass rcakk 
filled with this gns, nhtjuncd from carbonate of tiisi 
by sulphuric acid. Ndther the color nor tbe tj«ti 
of the cherries were altered at the end of flftea 
days ; and at the end of six weeks they were in 
same state as if they had been preserved io b 

Vegetable ^fitiV.— Vei;ctablea yield nine ie 
acids : — the oialic in rhubarb ; the tartaric io 
arinds, grapes, and mulberries ; the citric io o 
lemoui, and onions; the malic in apples, cherries, 
tbe gallic in elm, oak, &c. ; the benxoic io b ' 
trees ; the prussic in UureUlcaves, peach«bh 
and bitter kernels ; phosphoric in bariey, oats 

Salt Armer.— The salt-springs of Cheshire 
Droitwich contain 22 per cent, of salt. At Northwici 
Is a bed of solid salt. In most conntrlns, salt-rod 
is below tbe Borface, but in Spain, Sc, it u abon. 
The salt-mountain at Cordova is 300 feet high ; tut 
there are others still higher, and several of tbim. 
In Tyrol, the salt-galleries arc boriiontal ia • 
mountain. In Peru, salt-minea exist 10,000 lot 
above the sea. Tlie Cheshire beds of red-salt rock 
are 20 to oO yards thick, between thick bed* 
sandstone, limestone, and clay. At Cracow, 
mines extend several miles in vast cavemc . sua! 
by piUara of aalt, and have been wrought for 12 tt 
13 centuries. Salt is nther a result uf the d»* 
siccation of salt-lakes, or an accumulation of hoii- 
tontal strata, carried into nuiaaes by tjdea. 

La Place on the Form and Slrncturt oftkt £aWl 
— La Place has given the lollowmg very intereaOag 
results, as deduced from analysis, aod from 
experiments made with the pendulum in both 
spheres : — 1 . That the density of the strata of 
terrestrial spheroid increases from th« surface to tkf 
centre. 2. That the atrmta are, very nearly, re- 
gularly disposed around tbe centre of gravity of tU 
rarth. 3. That the surface of this sphcruid. vf 
which the sea covers a port, has a figure a litlli 
ditterent from what it would aasume in virtue of die 
laws of equilibrium if it became fluid. 4. That llM 
depth of the sea is a small fraction nf the difTcrenca 
of the two axes of the earth. 5, That the int> 
gularitiea of the earth, and the tiauaes which ditturh 
its surface have very little de^jtb. G. That tl* 
whole earth baa been originally flnid. " Thn? 
results," saya La Place, " of analysis and eiperima&t, 
ought, in niy opinion, to be placed amoug the 
nombcr of truths which geology preaenta." 

A cubic foot of air weighs 1*2 oonce; henne a 
column a mile high and one inch base, weighs i3'2 
ounces, and 15 pounds is equal to 5*G milca ; M 
diminislies in weight as the height, and in eUsOe 
forre or reaction as the bulk or cube of the height, 
both together as the biquadrate or fourth power; 
but in density as the logarithm of the height. Head 
at 44 milri, where the atmosphere eenaea to ndnt 
the light, its density is considered ooty aa a 10,000 
of that at tbe surfar^. 

A middle>8isedman conaames'46,000oubic Inohea. 
or 26 cubic feet of oxygen per day, making '^0 rc»> 
pirations in a minute, and 1*62 onbio inches at n^i 
that is 46,656 cubic inches in 28,800 rospinliBA 
per day. 



LoasoM.,— Piiatsd bv D. r*s«oii. «. Wfelie H«tm La«#, Mil* Eod— PuMlihtd by W. VairvAm. tl, 
EdUikiugb, X Maiistci.-41a*(ew. D Baini.— Uvtrpooi, G. Paiur 



Kav 



^ 



■M 



410 



MAGAZINE OF SCIENCE. 



RAMSDEVS DIVIDING MACHINE. 

Tbib vttluBble initnimeot ta Uie tDTeotion of Mr. 
Jeue Ranuden. to whom the Commiuioncri of 
Longitude gave the sum of :t'615, apon his entering 
into ao engagement to instruct a certain nauiber of 
persons, not exceetliog ten, in the method of making 
luid UKlng this machine, in tlie apace of two yeara, 
MBj, from the *28th Oetdber. 1775, to 28th October, 
1777 ; alio binding himself to diride all scctants 
uul octants bj the ume engine, at the rate of three 
abtUings for each octant, and six BhiUings for each 
brass lectsnt, with Nonius's divtaionji to half 
minutes, for as long time as the Commissioners 
should think proper to let the engine remain in his 
possession. Of the sum i.300 were given to Mr. 
Ramsdea, as a reward for the oscfulDess of his in- 
vention ; tnd £315 for his giving up the property 
of it to the Commissioners. 

The following ii the description of the engine 
given by Mr. Rsmsden, upon oath : 

This engine contista of a largo wheel of helUmetal, 
supported on a mahogany stand, having three legs, 
which are strongly connected together by braces, lo 
as to make it perfectly iteadjr. On each leg of the 
stand ii placed a conical friction-pulley, whereon 
the dividing wheel rests ; to prevent the wheel from 
sliding ofT the triction-pullies, the bell metal centre 
under it turns in a socket on the top of the stand. 

The circamferenco of the wheel is ratohed or cut 
into 21C0 teeth, in which an endleu screw acts. Six 
revolutions of the screw will move the wheel a space 
equal to one degree. 

Now a circle of brass being fixed on the screw- 
arbor, having its circumference divided into sixty 
parts, eAch divihion will, consequently, answer to a 
BBOtioa of the wheel of ten seconds, six of them 
will be equal (o a minute, Ace. 

Several different arbors of tempered steel are 
truly ground into the socket in the centre of the 
wheel. The upper parts of the arbors, that stand 
upon the plane, are turned of various sizes, to suit 
the centres of diffrrcnt pirces of work to be divided. 
^Mien any instrument is to be divided, the centre 
of it is very exactly fitted on one of these arbors ; 
and the instrameot is fixed down to the plane of the 
dividing wheel, by means of screws, which fit into 
holes made in the radii of the wheel for thai purpose. 
The instrument being thus fitted on the plane of 
the wheel, the frame which carries the dividing 
point is connected at one end by finger-screws, with 
the frame which carries the endlcst-scrcw i while 
the other cod embraces that part of the steel arbor 
which stands above the instrument to be divided, 
by an angular notch in a piece of hardened steel ; 
by this means both ends of the frame are kept per- 
ftictly steady and Iree from any shake. 

The frame carrying the dividing-point or tracer, 
is made to slide on the frame which carries the 
endless-screw to any distance from the centre of the 
wheel, OS the radius of the instrument to be divided 
may require, and may be there fastened by tighten- 
ing two damps ; and the dividing-point or tracer, 
being connected with the clumps by the double- 
jointed frame, admits a free and easy motion towards 
or from the centre for cutting the divisions, without 
uy lateral shake. 

Prom what has been said, it appears that an in- 
strument tbos 6tted on the dividing- wheel, msy be 
moved lo any angle by the screw simI divided circle 
oo tte arbor ; and that this angle may be marked 



on the limb of the instrument m\th Ike 
exactness by the dividtng*paint or traoer, whidi m 
only move in a direct line tending to the ecauiw 
and is altogether freed from Lliose iiiconvcsiiaiaH 
that attend catting bj means of a sl.r«ight edfe. 
This method of drawing lines will also prevent any 
error that might arise from an expansm- 
traction of the metal during the time of •' 
The screw. frume is fixed on the top of 
pillar, which turns freely round its axis, ao<& tim 
movei freely towards or from the centre of the wbee^ 
so that the acrew-frsme may be entirely guided by 
the frame which connects it with the centre t by 
this means any eccentricity of the wheel and tkt 
arbor would not produce any error in tbr diridui^ i 
and by a particular contrivance, the screw 
pressed against the teeth of the wheel always 
parallel to itself ; so^that a line joming the 
the arbor and the tracer continued will alwi 
equal angles with the screw. 

The large wheel A is 45 inches in diameter, 
10 radii, esch being supported by edge-bars 
bars and radii are connected by a circular 
24 inches in diameter and 3 inobei deop ; snd. 
greater strength, the whole ii cast m oue piece 
belt-metal. 

As the whole weight of the wheel A rests « bl 
ring B. the edge-bora are deepest where they JNI 
it ; and from thence their depth diminiaheti bott 
towards the centre and circumference. 

The surface of the wheel A waft worked very 
ind flat, and its circumference turned tns 
ring C, of fine brass, wss very exactly on 
corafereoce of the wheel ; and was fastened 
with screws, which, after being screwed as 
possible, were well rivetted. The face of 
chock being turned very true and flat in i] 
the flattened surface A, of the wheel, was fi 
against it with hoid-faals; and the two aurfi 
circumference of the ring C, a hole through 
centre and ^the plane part round it. and the li 
edge of the ring B. were turned at the same 
D is a piece of hard bell-metal, having 
which receives the steel srbor D, msde very 
and true. This bell-metal was turned rery 
an arbor ; and the face, which rests en a 
was turned very flat, so that the iteel arbor 
might stand perpendicular to the plane of the wbeelr 
this bell-metal was fastened to the wheel by lis 
steel screws. 

A brass socket Z is fastened on the centre at thft 
mahogany stand, and receives the lower part of tht 
bell-metal piece D, being made to touch the bell, 
metal in a narrow part near the mouth, to prvtotf 
any obliquity of the wheel from bending the arbor; 
good fitting is by no means neceseery here : linct 
any shake in this socket will prodoee no bad tSvi, 
as will appear hereafter when we describs tbf 
cutting-frame. 

Tlie wheel was then put on its stand, tht lower 
edge of the ring B, resting on the drcumfereace of 
three conical friction pulleys W, to facilitate ill 
motion round its centre. The axis of one of thess 
pulleys is in a line joining the oeutre of the eked 
and the middle of the endless -screw, and tbe oike 
two placed so OS to be at equal distances tnm oMl 
other. 

The lower extremity of the conical pillar P, br 
minates in a cylindrical steel pin, which 
through and turns In the (raniverse axis U, 
confined by a check and screw. 
To the upper end of the conical pillar b 



MAGAZINE OF SCliuNCE. 



411 



O. tn wU4>b the endlctfl-Mrtir tarns ; the 

the tcnm are forniRd in the mauuer of 
rums of conei joined by a cylinder. ThcBo 
I confined beCweeu half-holes, which prr» 
the conical parts, and do not touch the 
pKrta; the half-hules are kept together by 
rbicb may be tightened at any time, to 
be lerew from shaking In the frnroe. 
I Krew-arbor is a fmall wheel of brass K, 
I outside edge divided into sixty parts, and 
I at every sixth diTi»ion with 1, 2, Sec, to 

repretf nu a pivrt of the atand, having a 
ilit in the direction towards the wntre of 
If lar^ ennoKh to receive the upper part of 
ul brajs ptUar P, which carries the screw 
fame ; and as the rrniBtani'e, when tbr. wheel 
■ by the endle88*Bcrew, is against the aide 
It H, which is towarda the left band, that 
Iw slit is faced with brass, and the pillar is 
Igainst it by a steel spring on the op|K>8it<i 

thlfl means tbe pillar t5 strongly supported 
I tod yet the screwa may be easily pressed 
Igiliut the drcumfercQce of the wheel, and 
r will turn freely on its axis to take any 
t given to it by the frame L. 
% brass frame, which serves to connect the 
icrew, its frame, ftc, with the centre of the 
each arm of thia frame is terminated by a 
«w. that may be pasted through any of the 
t the piei'« Q, as the thickness of the work 
Svided on the wheel may require, and ore 
I by the Anger-nuts. 

B cod of this frame is ■ flat piece of tem- 
Bel, wherein is an angular notch ; nhan the 
■orew is pressed against the teeth of the 
llreace of the wheel, which may be done by 

the fiDger-screw S, to preai ogainst the 
r, thia notch embracer and presses agaitiat 
I arbor D. Tbe bottom of this slide has a 
[, whose plane ia parallel to the endlesn- 
md by the point of the arbor D, resting in 
ch, this end of the frame is prevented from 

The screw S. is prevented from unturDing, 
Ipning the lingor-out W, 



was not of a chemical natare ; that tt did not take 
place alowly, and in n rontinuoas manner, but that it 
was the calm and tranquil result of a mcchoitical de- 
composition. It may easily happen, that we may 
accidcntly notice, in a chemical operation, certala 
identical parts which have undergone no change, not- 
withstanding the alteration of the principal moss. 
jost as we find nnoltered flour Id tbe dough o( 
bread, chalk in silex, or foreign substances imbedded 
in crystals ; but hctrogeneoua portions, arranged in a 
series of regular formation, present a churacter pe- 
culiar to the conhgurationa in question, in which 
are formed, in a manner altogether remarkable and 
different from what ia nsually observed, and under 
the influence of a porticolor forco, lapideoua rings* 
free, concentric, end unconnected with each other ; 
between which, aliomate layers of lime, with the 
animalcules of the chalk are deposited, giving rise 
to formd having a solid nucleus with a free but 
aolid ring, snggesting to tbe fancy the figure of 
Saturn and his ring. — Jamea<m'9 Edin. Phil. Journ. 



I 



k^i^^^V^^^^tf ^^ ^^^■v-^^'^rN^^ 



SEAL ENGRAVINO. 

Thb art of engraving gems is one of extreme nicety* 
The stone having received its desired form from tlie 
lapidary, the engraver fixea it by cement to (he end 
of a wooden handle, and then draws the outline of 
his subject, with a brass needle or a diamood, upoa 
its smooth surface. 

The engrariag represents the whole of the seal 
engraver's lathe. It consists of a table on which is 
fixed the mill, a small horizontal cylinder of atetJ, 
into one of whoae extremities the toot u inserted, 
and which u mode to revolve by the usnal fly-wheel 
driven by a treadle. The toola that may be fltted 
to the mlU-cylinder are the following: a hollow cy- 
liudcr, for describing circles and for boring; ■ 
knobbed tool, or rod terminated by a small hall ; • 
stem terminated with a cutting disc, whose edge may 
b« cither rounded, square, or sharp, being in tbe last 
called a saw. 



FIGUTIED STONES OF EGYPT. 

bid rnocesAful microscopic observations on 
ired stones of Egypt, have enabled Ehren- 
■ ascertain that these non6guratioDS, resem- 
he rorpuacilea of Kaolin and rhalk, but tn 
I proportions, have in all probability been 
id by the same agents as the corpuscles of 
ir, only with grosser materials.' In fact, we 
feteiy recognise in these Egyptian formations, 
r they be in rings, discs, or spheres, and 
' in sixe from on inch to a foot, the animals 
Dhalk (for example, Ttxtieiaria glohulotnj 
Sndiaaolved calcareoua coverings have been 
id, in the progress of their formation, to a 
Vhich has disposed them in annular series. 
VeAppearances alto^ther different from those 
led by the fUnta and jaspers of Egypt, in 
ire meet with imbedded Polythalatnia only 
id there. The Uticr are not the corpuscles 
Ives, bnt only their form silicilicd by a che- 
peration, the nature of which is unknown to 
be small^ visible calcareous coverings obtained 
I in the soluble layers of the figured Egyp- 
ines, shows distinctly that the o[>cration to 
they owe their present condition did not eon- 
R composition and inbstitution, and that it 




A is the treadle which works the lathe. B tha 
crank. . C the foot wheeL D tbe cord. E iha' 
head or mandril. K a tool placed in the mandiil. 
The engraver holds the stone cemented on to a picca 
of stick by mcsDS of a sealiog-wax cement. 

Having filed the tool best adapted to his styM 
of work in the mill, the artist applies to its cuttinr 
point, or edge, some diamond -powder, mixed aj^l 



412 



MAGAZINE OF SCIENCE. 



with oUve oil ; nod turoing tbe wheel, the holds the 
etone agnintt the tool, so oi to produce the wuhed- 
for delincatioD and eroflion. A aimilar appHrutu is 
uaed fur en^aving on glass. 

In order to give the highest degree of polish to 
tbe eDgrsring, lools of boxwood, pewter, or copper^ 
bedaubed with moifttrnnl tripoU or rottnn-ntone, and 
lutly, a brush, ore f/i£tt:ncd to the mill. The&e ire 
vorked like tbe above steel instruments. Modern 
engrttvings on precious atones have not in general 
the same fine polish as lh« oocient. 



, STEAM AND THE STEAM ENGINE. 

fRerwmrd /nrm f»f!'' ^^ f"'^ coMctudni.j 

Thk name of Watt, using it in connection with the 
cteam engine, is certainly the greatest name that 
this history furnishes. Before Ua time, Uic steam 
engine waa a mere toy compared to that stupendous 
machine It became in his hiands. Refer to any of 
tfaoae engines we have described^ and it will be 
found that the same vessel acted as a steam cylinder 
and as a condenser ; at one moment a vast tjuantity 
of iteam was wasted to heat it. at another, a pro- 
portionably large quantity of water was neccttary 
to condense such part of the steam as hnd produced 
the atroke, — for it will be observed, that tbe cylinder 
was heated and cooled at every stroke of the engine 
at a vaat eapenditure of power; for, as Watt ob- 
terved, that in order to obtain the greaieat power 
firom the ste-am, tbe cylinder should always be kept 
as hot as the steam which entered it; that when the 
ateam was condensed, the water of condensation, 
and the water of injection should be cooled to J 00'^ 
Fahr.» or lower if possible. 

Pondering upon the method of accomplishing 
these important objects, it oocnrred to Mr. Watt in 
the year 1765, that if a communication were opened 
between a cylinder containing steam, and another 
veaael which wna exhausted of air and other fluids, 
the Bteam being expansible, would immediately rush 
into the empty vessel, and continue to do so till it 
had eatabUah«l an equilibrium ; and if that vessel 
were kept very cool, by an injection or otherwise, 
more ateam would continue to enter, until the whole 
was condensed. Thus was accomplished what had 
been considered imposaible by alt previous engineers 
—-the pndaetion of a vacuum without cooling the 
cylin^r. Tbe following cut will ahow Mr. Watt'a 
condenser, and the neighbouring parts of the engine. 




AAA, Is a cistern of cold water, situated be- 
neath the fltenm cylinder. B, is a pipe connected 
with the cylinder, C, the condenser. D. a valve 
opening from it to E, which is called the air pump. 
The valve G opens into a small cistern, called the 
hot water otateru ; and the circle H ia the end of a 
ptpa whkb leada to a pump oalled tbe hot water 



pump, and which leads to and lappliea the batter 
with hot water ; tbe surplus running off. I, b a 
pipe leading to a cold water cistern at top, and by 
an injection cock and a ruse tntu the coudenaer 
beneath. Before the engine is set goto;, tbe in- 
jection cock is closed, and stt;am is admitted to llie 
cylinder and the condenser, a port of the atBan 
eacapes through the valve M. and cariiea Ilia air 
with it from C- The injection cock ia then opened, 
and cold water being admitted, tbe ateam is condcn<cd, 
and the piston of the steam cylinder descends. \^'hea 
tbe piston of the cylinder rises, that of tbe air pump 
also rises, and leaves a vacuum beneath at E ; the 
vaWe D therefore opens and admits into E the 
condensed ateam of C. Tbe noit downward stroks 
forces it through the valves of the piston at E, and 
it is discharged at G ; admisaion and condensatioii 
of ateam going ou at C as before, C receiving tha 
steam of the cylinder at each stroke of the eng^ot. 
It next occurred to Mr. Watt, that tbe mov^ of 
tlic cylinder being open, tbe air which entered le 
act on tbe piston, would cool the cylinder, and oos- 
dense some steam on again filling it. Then he pro- 
posed " to put an air-tight eovor on the cylinder, 
with a hole and stuffing box for tbe piston to slide 
through, and to admit steam above the piston, ta 
act upon it instead of the atmosphere.'* This ws> 
his aeoond grand improvement, and while the pawn 
of the mechanism remain untouched, the expenia 
of fuel and waste of steam was reduced to nev^ 
a third of its former amount, and the macUMTO-^ 
now, properly, an engine moving by the forca rf < 
stearn , the motive power being derived preidosity 
from the gravity of the atmusjilwre. 

The other source of the loss of heat, by the air ef 
the atmosphere oooling the cylinder externally, 
which produced a condensation of the intenul 
steam, waa obviated in thought by inclosing Om 
steam cyHuder in another of wood, or of some other 
substance, which would conduct heat slowly. Uewsa 
the origin of steam jackets. 

It required but little contrivance after the ia- 
vention of a close cover to the cylinder, to make 
the steara drire the piston down as well a« up, alt 
that was neceasary. being a set of valves of saeh a 
nature as to admit steam alternately into one. and 
the other end of the cylinder, and discharge it fram 
one part, as it was admitted into tbe other. Bat a 
difficulty arose relative to the beam shore. When 
the piston was driven down by the atoMaphere, ■ 
chain reaching ft'oni the piston rod to the be am 
was all sufficient ; but when the piston rod was to 
posh tbe beam up as well aa down, tbe cboJa ba 
came inapplicable, a rack on the piaton rod and 
corresponding teeth on the end of the beam was 
anggeatcd, hut ajon abandoned, being noisy, vn- 
ateady, and producing much friction. There again 
Mr.Watt showed his transcendent talents by tbs 
invention of the parstlcl motion, certainly one of 
the moat benutiful contrivances that art or talrot 
could suggest ; it is ahown beneath — its object b to 
keep the piston rod sufficiently fixed to the beam 
to move it np and down, and yet keep peifsellj 
parallel ita course np and down. 

Suppose R ia the head of the piston rod. B the 
end of the beam ; this of course describes the seg- 
ment of a circle. The parallel motion consists of 
the moveable rods, which connect P Rwith the bean. 
F is a fixed point, all the rest ia moveable. As P 
is polled down the mo?eabIe end of F H, it motes 
in tbe segment I G J ; while B describes tlie seg- 
ment B L. Thus the beam would project tbe end 




^fAGAZINE OF SCIENCE. 



413 



\r. piston rod outwards, but the bar F H, which 
uected with it, by meuu of the iatcrmedinte 
woald project it inward* ; these contrary 




deatrox CAch other, and the pUton rod 
; verticil throughout its ooorsc — bo also doei 
od of the sir pump A Iv, 
lother difficulty to overconae wbj tho irrepu- 
' of the admittaoGe of the iteam, which lluc- 
d from rariooa cauaei, particularly the state of 
re. To obviate this, Mr. Wuit suggested ano- 
[reat improvement, a self-acting throttle vah/e, 
josted, that when the piston wna moring with 
nmt a velocity, it would admit less steam into 
ylioder, and lo diminish Its speed ; and, on 
ontrary, admit a greater quantity when it was 
ng too alow. This important purpose, Mr. 
. •ccDmptia)ied by an adaptation of the tent 
'j previously used for an anHlogous objert in 
ilhts contrivance la usually called the goTcruor, 
be tlius repre*ented and described :— 




ro balls C C are attached by bsrs to two 
M above B fi. They are connected below to 
moveable bars, which reach down to D D, 
"e they are attached to a aockett capable of 
Ing up and down tlm rod F. Suppose Q to bo 
ed round by tlte fly-wheel, or by any other part 
w en^iue, it would by lueiins of tlia bevelled 
:I oc the end of it, round tho wheel H. and this 
ipin>Ue P. As this turns more or less rapidly, 
ill of course the bulU fastened to it turn also ; 
by centrifugal force, the faster they move the 
Cr they will bo elevated, assuming with rapidity 
lotioii the position of the dotted lines as they 
1 the sorlul D riHts and pulls up the end of the 

Ecnd of which moves the throttle 



Talve, or that valve which admits steam from ths 
boiler to the cylinder, and Lhua the supply of steam 
la regnlated. 

Another very great improvement to ensure equality 
of motion was the applicaUon of a crank and fly- 
wheel, but as MrAVatt's idea was communicated to 
other parties before he bad put it in practice, ba 
ihuugfat proper to avail himself of what has been 
since culled the tun and planet wheels^ — a contri- 
vance easily anderstood by the mere repceseolatioa 
of it. 




Such ere bat a few only sf the inventloni of 
Mr. Watt, space not permitting ua to erpstiate more 
upon the subject ; we give below, however, the fint 
and second engine of this admirable mecbnnic, with 
a view to compariioii with each other, and with 
fonuer engines; a long dsscription is unneceasary, 
therefore we shall merely refer to the Toriotu parte. 




A is the steam cylinder. B Uie piston. C the 
upper valve. D the steam pipe. E the lower valve. 
F the passage to the cylinder. G the pipe leading to 
the condenser H. I the air pump. L the hot 
water pump. M N the tsppeu which work ths 
ralvea. O the cold water pump, which supplies the 
cistern R. It will be remarked, that the improve- 
monts shown in this over former engines, is in the 
cover lo the cylinder. Its case or jacket : the vb1v9 
from the top and bottom of the cylinder, the hot 
and cold water pump, and the condenser and air 



414 



MAGAZINE OF SCfENCE. 



pump. The defects arc that tbero ii oo fly-wheel, 
■lid no governor. Tbeie fire shown id the fallowiog, 
beiidi*« a very •apertor beotn, and mode of attach- 
rocnt of tho puioa rod to it, by meaiu of the 
paraltel motion. 




I SAFFRON 
la the ttlj^mitar of the ctochb oJlcinaliK^ dried on 
a kiln, and presaed into cakes. It is grown in va- 
riouB parts of Europe, a« well «8 in this country. 
A tract of land about ten inilea acrou ii a|)plied to 
the culture of this valoable product in Ctimbridge- 
abire. The greater part of this tract U an opeu 
level country, with few inclofiurcs; ftnd the practice 
thert is to crop the ]>Uq(8 fur two yeari, and then 
let it lie fallow tJte third. For planting, the fallow 
ground is well ploughed and manured, and af^er- 
warda dug by a narrow apaile into trencbej, wherein 
the rooti are put, and aubsequently covered over iu 
forming the next trench, the roots in which are in 
like maoner covered with the earth from the suc- 
ceeding one. The quantity of roots planted on an 
acre ii aboat 128 bushels. About the cod of Sep- 
tember the flowers appear. They are gathered be- 
fore they ere full blown, as well as after, and the 
ffiroper time for it ia earljr in the morning. The 
owners of the a affron- fields get together a sufficient 
number of hands, who pull off the whole flowers, 
and throw tbem by handaftU into a basket, and so 
continue till about eleven o'clock. Having then 
carried home the flowen. they immediately fall to 
picking out the stigmata or chivei, and together 
ith tliem a pretty targe proportion of the stylus 
»elf. or string to which they are attached ; the rest 
f«f the flower they throw sway as useless. Next 
-morning they return to the field, without regarding 
whether the weather be wet or dry : and so on daily, 
including Sundiyi, till the whole crop Is gathered. 

The nut labour is to dry the chives on the kiln. 
The kiln ii built upon a thick plank, that it may be 
BOTcd from place to [ilacc. It is supported by four 
short legs : the ouUide consists of eight pieces of 
wood of three inches thick, in form of a quadran- 
giilsr frame, about twelve inches square at the 
bottom on the inside, and tventy-two on the upper 
l^art ; which last is likewise the pcrpcodicoltr height 



of it. On the fore side is left a hole of aboc 
inches square, and four inches above the 
through which the fire is put tn ; over all 
laths are laid pretty thick, close to one aiiocbei 
nailed to the frame already mentioned, 
are thed plastered over on both sidesf as 
the planks at bottom, very thick, to 
hearth ; over the mouth is laid a hatr*rlolb|' 
to the edges of the kiln, sod likewise to two 
or moveable pieces of wood, which mn 
wedges or Bcrcws. in order to itretcb th« 
Instead of the hair-cloth, some people ose 
work of iron-wire, by which the HfTron iflj 
dried, and with Less fuel ; but the difficulty 
serving it from burning makea the luur-eU 
preferred by the be^l judges. The kiln is pi 
a light part of the house ; and they begin 
ling fire or sii sheets of white psper in thaj 
cloth, and upon these they lay out the wet 
two or three inches thick. It is then cove 
some other sheets of paper, and over these tb| 
a coarse bUnket five or sii times doubled, or ' 
of this a canvna pillow filled with straw ; 
the fire has been lighted some time, tlie wl 
coreied with a board having a considerable 
upon it. At firht they apply a pretty strong i 
to make the chives iweat as they call it: and 
time a great deal of care is necessary to 
burning. When it has been thos dried 
hour, they turn the cakes of saffron npcida 
putting on the coverings and vrdght ai 
no ainister accident happen during tbea* fifSt M 
hours, the danger is thought to be over ; and notUpi 
more ia requisite than to keep up a very geatla; 
for twenty-four hours, turning the cake rv( ^ 
hour. That fuel is best which yields thej 
smoke ; and for this reason charcoal Is pr 
to all others. 

The quantity of saffron produced at a crop I 
cert^n ; sometimes five or six pounds of wet 
arc got from one rood, sometimes not above < 
two, and sometimes not so much as is suflicic 
defray the expense of gathering and drying ; bol i 
ia always observed, that about five potindsi 
saffron go to make ooe pound of dry, for 
three weeks of the crop, and six pounds di 
last week. When the heads are planted TCryj 
two pounds of dry saffron may, at a medh 
allowed to an acre for the first crop, and 
foor pounds for the two reroaining ones, 
being considerably larger than the second, 
tain the second and third crops, the labour of 
gathering, picking, &c.. already mcntioaed*] 
be repeated : and about Midsummer, after 
crop is gathered, the roots mu»t oU be taken ' 
transplanted. The best saffron has the 
blades, — this being the mark by which 
aaffron is distinguished from the foreign ; 
to be of an orange or ficry-rrd color, and tO< 
dark yellow tincture; it should be choaea fr 
above a year old, in close cak^s, neitiier dry aai] 
very moist, tough and firm in tearing, of the 
color within aa without, and of a atrong, 
difTusiTe smell. Tliis drug bat been 
very elegant and useful aromatic ; it im| 
whole of its virtue and color to reotiflcd< 
proof spirit, wine, vinegar, and water. A 
drawn with Tincgar loses greatly of its 
keeping ; the watery and sinoui tinctarrs 
grow sour, and then lose their color 
made in pure spirits keeps in perfection U 
years. 



MAGAZINE OF SCIENCE. 



415 



[SPRING GARDENING. 

of M«rch and April are smong the 

CDltivator of the flower garden, as it 

for toirinK hi* seeUi, preparing hifi hot 

inmuiig up hxi borders. These ne- 

i% are olio accompanied by pleaaorea 

lerent, uot merelj to the suhjeot but 

for mauj an one neglectfal of such 

[all oihrr periods uf the year, a nuw 

aptntd, and induced to bodily exertion. 

It «ttoh is the cajw with all others as 

tves— the following remarks on garden 

l^od the coltiration of the tender an- 

lU titted. nnd it is hoped luefnl. 

tecpC those which arc very early in 

stiU be removed la March, and ever- 

it removed at this season or in April. 

may bo traosplauted with perfect 

larch and April, and if the garden to 

|«fv introduced is wet, or with a cold, 

Kuacions soil, they are much better re- 

[Khan in the autumn. The hardy annuals 

kich grow entirely in the open ground, 

Ira from the middle of March to the 

pay ; that there may be a succession of 

pnghoat the summer season. To sow 

•tir and smooth the ground, then, make 

iTeauon with the bottom of a garden pot, 

toad rlog with the edge of the pot, and 

w the seed over the smooth surface made, 

uk tooie fine mould over it, covering 

Ma an eighth of an inch to an inch, ac- 

the sise of the seed. 

pr annuals reqnire greater care in their 

I indeed there are very few private per- 

p not err roost egregioutly in vndeavonr* 

tco^scombs, baUams, and other planta 

r character. 

|r annuals, to be flowered in the highest 
brfection, must be raised on a hot-bed; 
mass of any fermenting material, that in 

Psitton produces a degree of heat con- 
Dve that of the atmosphere in which it 
There are various matters which will 
I this purpose ; some animal, others ve- 
td some tsetx mineral, as for example, 
da of coal dross, containlog pyrites ; but 
i common, and that which is roost eaaily 
BNUia of the amatenr who hai but ■ 
Ini is stable manure, we shall confine 
P giving directions for the management 
perial. When obtained from the stables 
krt-Ioad, which is quite sufficient for a 
bed, large enough for rearing annoals, 
f>f two parts, the dung of the horse and 
I or in other words straw, moistened and 
I bat not decayed. 'When the mass, thus 
bid in a heap, it generally produces a 
tful heat, too strong for being used as a 
Ibr it should never be forgotten that too 
is worse fur the plants than sowing them 
\ air. If the bed be much too hot, the 
I be blackened and ultimately destroyed; 
\ only a little hatter than is necessary, 
pill be drawn up, and become too weak 
^ ehanoe of success when afterwards trans. 
p the open air. As it is the fermenta- 
Dned hy the decomjHieition of the straw 
In the manure which produces the violent 
leap should be tumerl over with a dung 
^ IhrH times in the coune of a fortnight. 



till the dscomposition is coosiderahly advanced, ths 
whole mass of one color, and the straws, which 
were before tough, rendered sufliciently tender to be 
eaaily torn to pieces with the dung-furk. When 
the nisia U urlvod at this stsge. it may then b« 
formed into a bed. which may he of any convenienC 
length and breadth, according to the situation tod 
other drcumstaoces. 

In general, such a bed is covered with what is 
csUed a hot-bed frame. This consists of a box 
without a bottom, and with a moveable top, formed 
of a glazed sash or sashes. For a small garden, a 
box three feet wide, and four feet from the back to 
the front, will be sufficient. The back of the box 
may be two feet high, and tlie ^nt one foot. The 
hot'bed may be formed in an open situation, on a 
surface raised six inches above the general level ; 
and it should be three or four inchea wider on every 
side tfasa the box that is to be placed pn it. The 
cort'load of manure, which has been fermented and 
prepared for making up this hot-bed, ohould now 
be regularly spread over the bsae of the intended 
bed, and raised by successive layers to luch a height 
as the quantity of manure will admit. If, in build' 
Ing the bed by these saecessive layers of manure, 
cinder siitings, and the animal and veg^titble refuse 
of the kitchen, are mixed along with it, the heat 
will be the less violent at first, but it will be retained 
for a much greater length of time. 

The time for making a hot-bed for raising seed- 
ling annuals need not be earlier than the middle uf 
March, or beginning of April : since the plants 
which are raised in it cannot in general be turned 
out into the open air sooner than the middle of 
May. As aoon as the manure is formed into a bed, 
and the upper surface rendered quite Level, the 
frame and the sash should be set on it. In two 
days the disturbed fermentation will have recom- 
menced, and a steam will be observed under the 
glass. The surface of the bed may now be covered 
three or four laches deep with any light garden soil, 
and the different kinds^ of seeds may be sown in 
pots and pUced on its surface ; or if there should 
not be much best, or likely not to be much, the 
pots may be sunk into the manure. In other cases, 
where it is not thought necessary to sow the different 
kinds in pots, the covering of soil may be six or 
eight inchea deep, and the seeds may be sown on it, 
in little square or round patchea. This indeed 
the common practice. 

In such a hot<bed ss we have described, formi 
of only one load of stable manure, there is very 
little danger of over-heating the soil ; but it may fa« 
proper to observe, that neither the temperature of 
the soil, nor the atmosphere over it, abould ever 
much exceed 60°. It may fall as low as 48'^, or 
even 40*^, without the slightest injury to the plants ; 
snd it may be raised as high ss BQ°, or even 90^* 
without killing them ; but any degree sbnve 60" is 
decidedly injurious, by increasing the rapidity of the 
growth of the plants, and rendering them weak and 
sickly, and unfit to he turned out into the open 
ground. 

When the plants have come up, and shown two 
or tliree leavea, in addition to the cotyledons or 
seed-leaves, they require to be transplanted ; and 
this may either be done into small pots, or into a 
bed of earth, placed on a hot-bed, formed in the 
same manner ss the first, but with a smaller quantity 
of material, as much Ims heat is required. For a 
small garden, however, a aecood hot-bed is unne- 
cessary ; and all the transplanting and other pro- 




MAGAZINE OF SCI] 



I 



I. 

I 



preparatory to rcmoTal to th« open ^oand, 
may be carried ou in one hot-bed ; rare being taken 
to inan: the pUnta to tho open air by drgreoi, by 
tiUing the aaah ap behind at all timea* nigbt and 
day ; and after the pUnta are op, removing it alto- 
gether, during fine days. The great object to be 
kept in view, ta to make the plants as strong and 
viguroufl SB possible before torniDg them into the 
0|)cn gronnd, and to give them air, or to thin and 
tnutspbiut them whenever they ahow ayoptoma of 
becoming weak or drawn up. 

A hot.bed for trader annuals will never want 
what are called linings; u it is for the advmntcga of 
the plants that the heat should decline gradually aa 
tbcy Increase in site, that they may be the more fit 
for tranaplantiog, when the season arrives for them 
to be removed to the open ground. 

7%e nii Jvt gromin^ teniier annuai*.^~Tht soU 
used for filling the pota in whicti tender annuals are 
sown, should be as rich as possible, and yet quite 
open in ita texture : it should also be trtt from 
gmba and the cgga of ioaects. As soil of this de- 
scHption is not to be procured without some trouble, 
we shall give the following direcUoas for prepar- 
ing it; the best aoil is turf, but aa this is usually 
full of worms and the eggs of ioaects, it will require 
tlie following preparation -. — Take a spade deep of 
the surface of aome good rich pasture ; or if only 
the turf two or three inches thick, so much the 
better. Lay this up in a ridge, IB inrhea wide at 
bottom, 3 feet high, and of whatever length may bo 
required. Then take the fresh stable manure, which 
la to be used In making the hot-bed, before It baa 
been turned over, and lay it all round the turf and 
over it. diftributing it aa equally as posdble. If 
there is plenty of manure, in proportion to the 
ouantity of turf, the turf may he caMly heated to 
200". which will not only destroy all the insecU, Sec. 
but all the root and herbage, and moreover wonder* 
fully enrich the soil, by the diatilbtion of the gas 
evolving from the manure during ita fermentation. 
The manure must be tumeU over once or twice, 
while covering the turf, to prepare it for making the 
hot<bed; and when it la ready, the ridge of turf 
must be rtmoved to aome shed, or airy place, to 
dry it, when it will be fit for use. This U the best 
fKisaible suil foi annuals; but when put into the 
pota, it moat be mixed with a little vegetable mould, 
(formed uf dead leaves laid in a heap, and turned 
over from time to time till they rot) and aand. An 
old hot -bed, or decayed dung of any kind, ia not 
good for te-nder plants, aa it is apt to turn the whole 
•oil sour, or soddened (at least if much watered.) 
In the summer, turf may be seaaooed without ma- 
nure, by covering It with the short graas mown ofT 
the lawn, wluch will ferment ; but this plan ia very 
far inferior to the other, though it ia auperior to the 
old method of laying up the turf for a year or more 
before it waa used. By the hot-dung proceas, it 
will be ready lo ten days ; and not more should be 
prepared than will be wunted for one scaion'i sow. 
log and transplanting. 

Watering. -^ThvK are few pointa in which gar. 
deners arc xo apt to trr as In watering ; and the 
general fault is, that they give their plants too much. 
This is a fatal error for plants in pots, since over- 
watering will soon bring on the svils attendant on 
Imperfect droioage; it is even dangerous to syringe 
the planta too much, though a little water thrown 
over their Icflvea occaaiunnlly is very useful in re- 
frrabing them. H the plaui&ahouM 
or htfcctcd with iuaccts, the iHit abuuld^'faki^^lxV 



turned on ita side before the tyringc is 
and this plan haa only the advantage of 
aoil in the pot from becoming aoddoi with loo 
water, but also of enabling the operator lo 
the lower aidea of the laaves, where the red ^ 
one of the greatest enemiea of plants In poll 
nerally commcocea its depredatiooa. Wbi 
plant is too large or too delicate to admit of t] 
betog laid on ita side, two pieces of board « 
notch cut in each, to allow room for the atem < 
plant, and wider than the rtm of the pot, aim 
laid over the earth, so as to carry off the w»t« 
&lts from the leavea. 



ACARUS GALVANICUS, OR ACARI 
CROSSIT. 
Ocs readers will remember the ejcdteoent o 
in the year 1H37 by the announcemeotr thai 
Crosae, of Broomfield, had observed the dovi 
ment of certain tniects incident to the long-cont 
action of galvanism. Little additional tnfbra 
on this mysterious subject haa nnce tranqiifO 
Tuesday, the 16th instant, when a paper froB 
Weckea, of Sandwich, waa read before tlie Li 
Eieclncal Soeiefy, detailing the aacccaafal repe 
of Mr. Crosse's experiments. Among the m 
which aroae in connection with the original ei 
meota, the possibility wu urged that the on c 
insects might be in the air. M r. Weekea'i ei 
menta were so condaoted that this objectian e 
scarcely tenable. A well charred block of 1l 
conuining a circular groove, to receive ■ beU- 
wu the base of the instrument. The groov 
filled with mercury. A tumbler, containiDi 
aolntion of silicate of potass, was beneath the 
the aillca waa obtained by aubjecting to a fti 
beat a piece of fine black flint, obtained oat I 
centre of a " bowlder," selected from amnsuai 
lying on the abore at Sandwich. Tlw ul 
united to tbe potaaa by a furnace heat ; tho 
quenched in boiling water. The aolntioa an 
mediately covered and filtered under cover, 
things being prepared, the voltaic current wai 
through the solution on tlie 3rd of September, 
and from tlmt date to the present time th« 
nitns has not been disturbed. At tbe end o 
tobcr, 1811, the first insect was observed, < 
16th of November, five were discovered. Siae 
date insects have been repeatedly seen. Wk 
not omit to mention that the beU-glaas was | 
in toUU darkness, the screeo lieing only rci 
when the progress was being examined. Mr.M 
mentioned that he had another apparatus in s 
very simitar to this, with the exception that til 
is filled with oxygen i aud expressed an ontld] 
that be should aooner or later detect in 
there. Thia expectation was raallMd • hw 
ago. In an appendix to hla oomronnloatioii 
February 27th, he sutes, that on the p 
morning, he perceived eight or ten folUgTow 
In vigorous loeomotion on tbe inner ssiisoi < 
air bell. — 7Vme#, 




Volt. 1 , 2. onrf 3 qf IkU Mogmtm$ ore nam 4 
elegantly bound in GotM ami Lettertd, 

Br. taeh. 
All Votumea iMtnttH by the Proprietor* i 
EuBOStiRD Ciotb ; tbe Tiile in a l*Ati,rm 
the pMblitker'M Nmnt, in gold, cm ih* back 

*t:onvA/or Binding, (Lettered J may •/!«« h 

y l&ftff Pnbittber, prtct U. 



J 




tfUi 
rf tnlphur on iron 

cotorof , 

htof , 

Of, tnxail , 

, Volu'i 



416 
. 15 
87 
408 
85 
249 
289 

Ined in anow 16 

r tteel with silTer ..266 

(SUdeof 290 

MovfiMture of 99 

53 

cod ^u, to make 221 
tography, Batea'9 ..377 

o( gues 94 

WBUin.134,147, 

167, 173 

rot fish 339 

masonry 397 

BlecUicity 400 

IgDetUm 1G4, 202 

, distribation of . 3, 10 

lUes in charm IG 

oulhflnware and 

237 

390 

for increasing the 

Wtm gas '^64 

for poliriittion . . 327 

d meaao. tin ting 331 

»t engrariag 292 

acrew 100 

lore 282, 374 

ftted hydrogen gai, to 

221 
looogelation ..311, 351 

making of 126 

hi and hail 24 

iml illustrations ..385 
, iteam narigation'on 48 
height or.. ..'.. 51 
refraction, 263. 291 
berical dust ,.,...,.400 

a ma<:hine .«. 97 

93 



r, qnnlittesof 398 

llectro-matpictic phnt- 

ilegraph 225 

, managing of .... 

I. small air 

1^ medical 

oentrifogal mltU. 
pbenomena of 

pie 



39 
B5 
80 
106 
276 
24 



Bates's anaglyptography .... 377 
— poljangular k^eidoscope 161 

Bear's grease 80 

Bclier hydrauliqne 89 

Ben nuts 96 

Birds in reference to gmrdena 296 
Bismuth, crystallization of . 28 

Bittering. or bittern 80 

Bituminous shale 224 

Blacklead pencil drawings . . 386 

Black reviver 80 

Bleaching ivory 120, 136 

liquid 80 

Blight, observations on 46 

Blow-pipes 241 

Bona glue, nuking of 48 

Bones, pctrllled human ... 7 
Books, preaerration of from 

insects 263 

Botanical notices. 11,45,84. 

116,156, I8R. 196 
Bramah*s bydroatntin prnaa.. 217 

Brieka, durability of 288 

Bridgeman'a oxygen lamp .. . 65 

British Museuu . 16 

Bronie for electrotype medals 352 

of the anctenU 400 

sUtnea 214 

Bucket engine 106 

Bug poison 80 

Buildinga, covering of 368 

Bulbs, mitnogeroeut of .... 306 
Butterflies 379 



Calcalsting machine ... 241, 250 
Calico printing by electricity 230 

Calotjpe pictures 139 

Camera obacura, improved . . 400 

new 20i 

Camp vinegar . 112 

Camphor, kinds of 40 

Carbon and silicon, conversion 

of 171 

Carbonic acid gos, to make 220 

Carthamus 131 

Cassava 14 

CaterpiUari, to destroy 160 

Cathcrwood on the lunga. . . . 232 
Cavern temples of India . . . . 201 

Canae of the rainbow 256 

Caosea of drowning 333 

Cement, fire and water proof 320 

Centrifugal pump 106 

Cephalic BDoff '. . 40 



Cerography 34 7 

Chains, mnnufactnre of 281, 300 

Chain pump 106 

Changes of craba. - 83 

Chara, animalculea in .... 16 

Charcoal as a mannre 13 

Chelsea pensioner 112 

Chemistry, how to study 

cheaply 21, 45 

Chick in the egg 64 

Chimniea. draft in S88 

ChiDeae weights 79 

Chlorate of potaaa * 235 

Chlorine 172 

Churning, new method of ...304 

Circulation, vegetable 247 

Clegg's gas meter, &c. ... 17 

Clocks 129 

Clock electro-magnetic 297 

Cloth, priming, &c. o( . . • 28 

Coal from India 336 

dost as manoro .... 16 

CochineJ Insect 223 

Coin, gold, silver, and copper 16 

Coins and medals 125 

Coke, manutacture of 271 

Color of agates, canae of. . . . 87 
Cognise brandy. Imitation of 375 
Copying machine, substitute 

for 24 

Composing machine 187 

Composition of colors 381 

for covering buildings.. 368 

CongelDtioDs artificial.. 341, 351 

Corn plaster 112 

Cotton plant, the 230, 244 

Court plaster 112 

Crabs, changes in 83 

Cranes 57 

Crystallization, principles of 150 

of bismuth 28 

Currents of the ocean 195 

Daffy's eUxir . .". 112 

Daguerreotype, improremrnt 

in 2, 141 

plates, etching of . . 189 

platM, preparation of 136 

Damask powder 112 

Data, mechanical 328, 345 

Davenport's electro-magnetic 

engine 49 

Death, uncertain signs of. . . . 308 
Decomposition of water .... 49 
Dentrirricea * * 8 



IXDEV. 



I 



T9f 

Oepi^torin ® 

Defby*hirf! diamonilft 320 

Destroying caterjjiUurt .....160 
Dtainoad, comhuiiion of . . - 273 

DiuOTery in printing 316 

2 4lu.bl6 240 

DiitUUd w&tert, mftkinR oT 

399. idh 
I^stTtbation of animmli . 3, 10 
Dividing engioe, Kimiden'i 410 
Domestic gsi apparatui .... 81 

Doric architeclure • 281 

Dorpat telescope) 33 

Drawing with black-lesd pen- 

cils 386 

Dropping bottle 360 

DrowiuDG^t recovery from ..224 

Dutch drop! 153 

Dyeing, mordants for 181 

Dyes for the hair H 



Earthenware and gliss, an- 
nealing of. 237 

Eartbraware paving 180 

gluting of 30 

Eartbqask« 320. 403 

Eccentric pump 106 

Eclipses 108, 114 

Egg, fignrea in relief on ... . 39 

Egyptian architecCurr 153 

Eidograph. Wallace's 265 

Electric kite, cnution about 125 

. thermometer, SoUy's . . 259 

ElectricHl cell 70 

- . ei[>erinientj.. .. ...... 169 

Electricity of slcaiD ^.. 39 

odour of 20C 

Electro-niagtiet, Radford's ,. 394 
Electro -msgnetic dock .... 297 

. etigiue. Skipsey'a 402 

Sturgeon's 233 

. engines 49, 145 

printing telegraph .... 225 

Electro gilding 384 

niugnetiitn 121, 193 

Elydnric painting 38 

Encaustic pointing 61, 66 

Engraring. etcliing. *c. 132, 

174, 205, 246, 277 
Eograving in imitatioD of 

chalk 398 

Eisential oils 103, 109. 118 

Etching 174. 205 

and dyeing ou ivory . . 403 

Dagnerreotype plates . . 189 

Eraporation of Ibe sea .... 136 

Experiment, curiana 250 

. with a tulip 64 

Experiments, elrctrical .... 169 
meteorological 224 

— miscellaneous . . 23, 56. 

128, 168, 200, 2.12. 280 
r...-r.mfiu« on human hair 48 

uf arcbca 23 

.- lead ore 179 



Ferguann's rlnrk 129 

FerinentaltoD, Ibe paaary . . 251 



fcrro-fryamde of pota«h, ar. *** 

tion of, on iodide of Biher 214 

Figured atone, of Egypt . . .^], 

rilter, May'a 233 

Altering niachinea for water 41 
I'irc produced from cane. ... 64 

Fish, anatomy of 339 

— — light from S0| 

prcserTBtion of 373 

smsea of 367 

Fishing through the ice .... 48 
Fiikes of snow, form of., ,.337 

Flame, ever-bamiog. 13 

Fluo-boric gas 222 

Fly water 80 

Poena of lenses, &c., to find 394 

Form of the earth 408 

Formation of rocks 160 

■ miata 4 

Fossil infnsoHie 392 

Franklin's clock 129 

Frannhofer's telescope 34 

Friar's balsam 152 

Fresco painting . . 240, S71, 304 

Friction 400 

Fruit, or seed vessel of plants 196 

preservation of 408 

Fuel for steam engines .... 15 
Palminating compound< 391, 406 



Galvano-pUstic wonders .... 192 

Galvanic plant protector 312 

reverser 408 

Glilvanometer 25 

Gaonal's prooesi to preserve 

meat, IStc 63 

Gas from pyroligneous acid. . 48 

— apparatus 81 

— meter, Cle^s, 3cc, .... 17 

Gases, preparation of 2'20 

Gaseous analysis 94 

German paste 152 

Gilding ou steel 4 

Glass church bella 160 

phenomena of 239 

— — ■ tubes as water pipes . . 240 
unannealed, phenomena 

of 182 

GUiing of eartheuware ... 30 

Ooddard's polariaoope 113 

Gold. poUble 187 

Goniometer 36 

Gooch's astronomical illus- 
trations 386 

Gothic architecture 374 

Granite 77 

Gnus lawns 224 

Green-house plants 252 

Gum paste 152 



Hair dye* , B 

Harrowgate water, artificial 184 

Headings fur beer 184 

Health, to preserve 360 

Hearing trumpets 356 

Hest, elfect of upon crystals St.'i 
Height of the atmosphere .. 51 

of waves :i36 

Hemp from bean stslki .... 192 



Henderson's 3-wliealcd 1 

Herco Ion tram 

Hippocraa . . 

Horticulture. . 

Hot hiatt, apparatus fbri 

Hot-bouse thermoUKten 

Huile antii|tic 

Human hair, experinealS' 

time piece . . 

Humming nf gnata 

HydrosUtic press M 

Hydro-zincic gas, to procurijj 
Hydraulic engines ..9, lid| 
Hygrometers ^M 

Ice caves, oatnral .^H 

Ignis fatnos TU 

Impressions from medals . . i 

Indelible ink H 

India coal P 

Indian architectore .... ~~ 

Indigo , ., 

Infuaoria, influence of 

upon 

Inertia 

Ink, indrtihie. ne< 
Insects Bh'l theirpli 

number of in 

ludiofl Tapour . . , 
Iridium and oaminmj tot 

Iron 

■ meteoric , . . , 
IsingUfS, mudlap! 

action of in lining U(|i 

Isomethcal perapectiva . 

Japan varnishes 

Kaleidoscope, Bates's . . 
Kaleiduacope, chAocetori 

Kalorama 

Kites, paper 

La Place on the form of 

earth 

Lathe, Wie'it"'"' 
Lannchin. 
Lead oru < 

ore 111 GLiiuiorg4A*htn I 

Leggett's chemical e«kir 

printing ^* 

Length of da;s .... 
U{e boat, new., ,, , 

Light 

—~-~ travelling of 
■ of the moon 

from stale fish. . . 

Light-houK^, the cast 
Lime, use of in plantlag 
Line engrating 
Lip Batre . . . 
Lama, the wool of ,, 
Lunatics 



Msdilnery, coalriv&ng 
duration gf , . 



INDEX. 



4l» 




dectric ^p&rfttus, 

s 89 

ffpark ftbawn 248 

Ikle, com pua tire, of 

Ite 48 

\t diefnical chang«« in 311 
f spirit from the .... 87 
|SuU»ce OD the globe, 

«f 324 

1^ atuningor 347 

|]«, screoKth of 262, 269 

|o en^ariag 377 

npld filter 233 

pntridit; of 288 

■ieal dau 328 

I nceipts . . 3. 40. 80, 
152. 184, 215. 256. 272 
0^1.48,119,160,192. 
288, 336. 368, 376. 3B4 

ued for coini 364 

Acduit 400 

KM 219 

•per . . ; 16 

nttroying of 363 

Dope, binti oa 55 

toweU*i 369 

opic objecU 402 

tallow 48 

ualyBU of .. .. 134 
eiperioienti .. 128 

on of 4 

na ind tnde winds. . 298 
y tpota upon . . 67. 76, 313 

jhti for dyeing 181 

BO leather, to maDufac- 

* 406 

pictares .143 

' aealculatingmaohUie 24 1 

in rifors , ..336 

• powera 238 

tain flax 53 

ttrings ..165.207.228 

lof light WO 

Katiire 392 



debt of England, 

ibtof 64 

al ice cares 88 

■tioD of the Atlantic . . 48 

! 333 

eUlUc aubitance .... 240 

'• gaUania reTerser408 

, to procure . . 220 

221 

month.. 32, 72, 

144, 176. 208 



, the 343 

of electricity 206 

flMcntial or volntiJe, 103. 

109. 11 @ 
Tf, Hend«rton'» .... 1 

ni« remuna 28B 

b of apringa 155 

bun, to obtain S55 

It of iron 160 

pn lamp 65 



206 



Paf« 

Palingenetj 127. 133 

Paper kites 198 

Papier nuche, improved ... 29 
Parchment, preparation of for 

painting 24 

Paris telegraphs 48 

PatenU, the law of 106. 122 

Paving witb earthenware. . . . 180 

Pearl water 216 

Pearls discolored, to whiten 400 

Pencil drawing 386 

Persian wheel 9 

Perspective, isometrioal .... 209 
Perspectograph. Wilcox's . . 305 
Petrified human bones .... 7 

Pbenooaeoa of glsss 239 

Philosopher's stone 149 

Phosphoros 316 

Phospburetted hydrogen gas 221 

Photography 248 

Picturesque in painting w . . 261 
Pile-driving machine, steam. 

286. 329 
I^nkaa*a domestic gM appa- 
ratus ^ 81 

Pitch and Ur 357 

Planets, magnitude of ..... . 48 

Plant protector, galvanic ..312 

Planting fruit trees 192 

Plnnts, temperatoro of .... 240 
Platinum, to obtain pare . . 19 
Potariscope. Goddard's . . . . 113 
Polarization of light. . 37. 68, 

101,. 175 
Polarization, the canse of the 

rainbow 256 

Polarising ap|>aratiu 327 

Potable gold % 1R7 

Pouncing deitigns on cloth . . 70 
Powell ficLealaod's microscope 369 
Predicting the weather .... 69 
Preservation of books .... 253 

fish 373 

fruU 408 

meat 63. 224 

Press, Brsmah's hydrosutic 217 

Primary rocks 338, 350 

Primingof cloth for the painter 28 
Prince Rupert's drops .... 320 

Printing, discovery in 316 

Pumps 106 

Pamp. SutclifFo's roUtory ..361 

Putridity of meat 288 

PyroUgneons acid ..86.91.370 
gas from 48 



Radford's electro -magnet . . 394 

lUilway traffic 224 

Ramsden's dividing machine 410 
Recovery from drowning. . . . 224 

Refining of snlphar 190 

Reflecting telescopes 73 

sod refracting telescopes 73 

Refraction & reflection. 263, 291 
Remains, organic ........ 288 

Reproductive organsof plants, 

188, 196 
Rivers, motion in ........ 336 

Rocks, formation of 160 

Rowland's Macassar oil . . . 8 



Rules for preserving bMllh.. S60 
Rupert's drops S2& 



Salt mines 408 

Safety valve 330 

Sawing mill in 1593 48 

Saxtoo's magneto •electric ap- 
paratus S9 

Sculpture in Great Britain . . 395 
Sea horse 259 

— water, qnalitiea of 143 

— worms 120 

Seasoning of timber G 

Seal engrsriog 411 

Sections of wood for the mi- 
croscope, cutting of .... 394 

Seidliti powders 216 

Shorpin's blow<pipe 24 1 

Shooting stars 365, 371 

Silicated flnoric gas 222 

Silicon and carbon, conver- 
sion of 171 

Silicon, the base of flint .... 229 
Skipsey's eleDtro-msguetic en- 
gine 402 

SUdeof Alpnoch 290 

Small air bslloona ........ 85 

Smoke, to conrame 336 

Snow, air contained in ... . 16 

and its crystoibntion . . 337 

Snuffs 40 

Soda, nies of 71 

Soila. nature of 212 

Solly's electric thermometer 259 
Soluble glass 78, 82 

Sound 64 

Speaking & hearing trumpets 356 
Specific heat. Regnault on . . 192 
Spectacles, when to be used 368 

Spirit from the mango B7 

Spots, &c., in the moon 67, 76 

Spots on the sun 376 

Spring gardening , . 415 

Springs and fountains, origin 

of ..15ft 

Spruce beer • . . . 256 

Staining of marble 347 

Steam and the steam engine, 
48, 243.268,292,308,332, 

348.372. 388 412 

Steam engines, fuel for . . . IS 

power of 342 

Steam pile-driving machine 529 
Steel, obtaining of 43 

— tempering of 88 

plates, for engraving .. 59 

gilding on 4 

Stratified rocks 338. 350 

Straw plat 295,302,310 

Strength of materials . . 262, 269 

substances 71 

Sturgeon's dectro- magnetic 

machine 233 

Stuttering, its cause and cure 
Sulphur 

— refining of li 

action of, on iron. . . . 19^ 

Sulphuretted hydrogen gas, 

to make 221 

Sulphurous acid gas 82V 




420 



INDEX. 



I 



Pnge 

Son, the. u a muitq of heat 237 

— probiibl)^ tnbabitct) 117 

Solcliflio's roUtory pump ..361 

Tkir water 272 

TkUow, mineral 48 

Tu- and pitch 357 

Taitc, the ornn of 254, 260 

Teeth, medicinM for 8 

Telegnphic rulwa^i 3S4 

TeLnicope*, construction of 73 
Tempenture, dlinlovtloD of 

on couts 20 

Tempcratorc, daily 37G 

of plant* 240 

TempeHn^ of Bteel 88 

Terro-mrtAlUnnin 272 

Test for acids, Ptc 23 

Tbennometerv forhot-hoaBoe345 

Thermoitat 257 

Tide* 34,53 

mitfy't falow.pipe ....241 

Tf me told hj a shiUrnc 314 

Timber, Reasoning of .... 6 
Tlnetores for the teeth .... 8 

TiimhiK ADd sincing 52 

Xobacoo^ 319 



Tooth powdtn 8 

Tracing de«k 24 

Trade winds and monsoons. . 298 
Traosferria^ engr&vings to 

piaster 376 

Travelling of light 64 

Tulip, experiment with .... 64 



Ore's thermosUt 257 

Uaca of soda 71 

VegeUble adds 408 

circulation 247 

soils 213 

Vegetables, soaceptibilitj of, 

274, 283 
Vegetation in atmospheres of 

dilTerent deoslUei 64 

Velocities of wind 120 

Vibration of wires 88 

Vinegar from wood 86, 91 

Voltaic combinntioDS 215 

VolU'sair lamp 249 

Volatile oils 103, 109, 118 



WagstatT't air pump ... 
Wallace's eldognph . . . 
Watch, beats of in a day, &&1 

Watch glasses 

Wster impregnsled with fiar- 

boaic add gu 2CJ 

Water, impregnation of with 

oxygen 183,/ 

Water-proof cloth 

Water ram 

Waves, height of 

Weether. rules for J«dgiog . . 3dS.I 

Weight of tlr 

West India coal SM) 

Westphaliao eMeneeof tmokftj 
Viliitening discolored pearls^ 

Wtgbtman's lathe 

Wilcox's penpectogrmph • 
Wire ropes of flat Iron . . . 

Wires, Tibmtiott of 

Wood vinrgur 86, 9l1 

Wool of the lam ft SMI 



Young's composing m^Alwa igf\ 



Zincing and tiaalng 



END OP THE THIRD VOLUME. 




e 



o. njucu, rkiMtn, wmn% ainiia uas, huls sitb koas.