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Full text of "A manual of scientific enquiry : prepared for the use of Her Majesty's Navy and adapted for travellers in general"

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3PUE.FARED FOK THE 



USE OF HER MAJESTFS MVT : 



AND ADAPTED ^m TRAVELLER?^ IN GENERAL 



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EDITED BV 



Sib JOHN F. W. HEiiSCHEL. 







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iLISHKD BY AUTHORITV 



€^e aurlis ©omtittsgtoners of tfte SUmtraltj) 



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L O N D O N : 



JOHN MUI. 



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Av^ ALBEM.iELE STEEET 

•HETt TO TUE ADMIRALTH.. 



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MEMORANDUM 



BY THF, I,OBl>S COMMISSIOJSE 



OV THK ADMIRALTY, 



Relative to the Compilation of a Manual of Scientific Enquiiy, 

for the nse of Her Majesty's Navy, 



It is the opinion of the Lords Coimnissione'- .f the Admiralty tliat 
u would be to the honour and advanta<ro of tl- Navy, and ^onduc-,. 



to th 



general interests of Science, if new lawiitie^ 



i eucourag-e 



m^nt were o:iven to the collection of mfbrmation upoii.dpnUfio subjJJ^ts 
by me officers, and mwe particuhrlv by the meduj oiEcers, of Hf^r 
Majesty's Kavy, when upon ibreign service ; md lucir Lordships are 
C- ;rou3 that for tUia purpose a Manual '~ 
instructions for oliservation and for rec 

Ineir Lon^-^:ip^ do not consider it u.,i:essarv that this 



t' irous that for Jii^ purpose a Manual be con.pil.-d, givinp sreneral 

various branches of 



'^cience. 



oi 



n* 



Manual should be one of V017 deep and ab... .se research. Its direc- 
tions should not re^uiie the use of nice ap^iratus and instruments : 
they should W -ciitrally pi,.;.,, so that men merely of good intelli- 
gence "■ H fv,;,, acquircaicnt way be ablo ,0 act ur-- them : yef, in 
pointing out objeets, ,;r.ri methods ^t observation ^nd .ccord, tht v 
might still serve as a guide to oii.^^.^ of high attainment ; Aud il viiil 
be for their Lordshipa to consider whether some pecuniary rev ... 'd . 
p: emotion may not be given to those who succeed, in prod^jr-in^ 
c . .. 3Rtly useful results. 

Their Lordships are aware that in tlie instructions pre^^.jd a.aler 
the directior=i 01 me Royal Society for the Antarctic expedition -in 
the bmtsfor collecting information given to o.^.cers on the expedition 
to Cfliaa, iu the excellent book by A. JacL.u, entitled '-What to 
observe," and in other documents and pubii^tions— the luil^^sidircc- 
tjous are to be found ; but they are either more yoluminous or more 
rdosely confined to objects which regard particular localities than is 
to be desired fo- a general Manual. Their Lordships are, therefore, 
'lesirous that a new compilation should be made, and are n-^ed that 



... (} 




4 

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i 





iV 



MEMORANDUM. 



their ^^ishes would be best met if they could obtain the assistance of 
oOK'O of our most eminent men of Science in the composing, by each, 
of a plain and concise chapter upon the head of enquiry with \vhich 
he might be most conversant, and they have been readily and kindly 
provnised the advice and labour of Sir John Hersehel in revising the 
whole- and preparing it for publication. The several head^ of en^ 
quiry are as follows ; 



Astronomy 

Botany. 
Gcograph 

Gec^ 
Mineralogy, 



v a.--- 



Hydrography 






Magnetism. 

Meteorology, 

Statistics. 

Tides. 




4 



Indepeiv-n-.tly of r -tters of exact scien-e, their Lordships would 
look m nianv instances, for Reports upon National Character and 
Custom^ Religious CoreumnlPS, Agriculture and Mechanical Arts. 



Lan^ru 






avigation^ Medicine, Tokc 



of value, and other sub- 



•ects- but for the;, only very general instructions can be given, 
though yaluable Reports may be expected from men of o^ ^rvatK)n 
f rid Intelliuen- :^ acting under the encouragement wh)ch the noticp 
of whatever is well and usefully done is certain of affording. 

If would oive additional value to each cha|.a- if the name of hm. 
bv whom it might be composed should be auixed to it ; and their 
i:ordships are anxious that no time be lost in the prepa^t.on of tins 
work Thev are sending a surveying vessel to New Zealand and 
have others in the Torres Straits and in oiher parts of the world. A 
new establishment is contemplated at Rorneo. Exped.Uons ar. pro- 
arch of Sir John Franklin. They have cruisers in ey(.y 

it sometimes 



ijoseti ill ^0 



ea ; and whore the ships of the navy are not pieseni 



J 



hai>pen 



that tne vessels of the merchant are conducted with i--h 



intelligence and enterprise, and lor all of these the work propos.d 



would be valuable 



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XiiE Memorandi 
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"IS its origin 



.iie Ed;^ r to in 
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panares either in 
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The Memoranduo) of fl 



ords Commissioiiers of the 
Admiralty, prefixed to the present work, so fullv ex-^ 



plain? it 



-s 



origin 



and object, that 



It onij 



BMx^ 101 



the Editor to indicate the reaso-i which 



rem 

have neoes' 




what may appear to be in a certaiu deo-ree 



to 



departurp^ from the plan as therein sketched out~de 
partnres either inevitable in themselves 



5 or sar 




nea m 



their progress by their Lordshir ■ approbatioii, and which 



} 



though mvolviiig a material inere 




in the bulk of the 



first 




;e CO Litem 



volume beyond what was in the 

plated, can hardly fail to be regarded as addiiig still more 



' ot Its proving useful in 



materially to the probability 

li«-theri,ig the collection of scientific information. 

On receiving from the eminent authora of the several 
chapters into which this work is divided, 11)^:, respective 
contributions, drawn up by them at the particular 



and 



personal request of the late lamented Earl of Auckland 
(to whose enlightened 2eal lor the improyement of scie 




I 3 




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PREFACE 



the work owes its original conception;, the Editor at once 
perceived that, while, on the one hand, the total amount of 



* 1 



matter c.^itributea cuuld by no poBsibillty be compressed 



,1 



into 



the r^niali compass uiigxiia.xij 



oridnally intended (even v*hen 



2 ^Tl hi 



i 



1-^drced bv the Retrenchment oF some po>^^^oiis m his 
opx.au- : 'ss vitally essential, and wliicli the authors of 
thosG portions, on his representation, most readily agreed 
to abbreviate) 



-on the 



other, those contributions bore 
i'\ lence of having been drawn up with so much carr; and 
preelsion, and elaborated with such consummate ability, 
that any further attempt to reduce them withiu those 
limits would hav- been at once presumptuous on his part 



and most injurious lo the efficiency of the work itself 
It is hoped and believed that the instructions on eacl 



subject tiuated of ar^ 



i.^ 



.ch as completely to fulfil the 



views of tht: Memorandum, in so far as it is possib^ 



j-% 



- > 



con- 



sisti^atlv .,^tii the nature o 



thcv should do so. 




f the sciences treated of, that 

are some — such .3 Ter- 



restrial Magnetian— which it is impossible to divest of ■' 
certain degree of abetruseness, and m which no ul^^erra- 
tions wortu recording can be made without the aid of 
instruments and methods of observatioti and reduction de- 
cidedly both nice and delicate. The s^.^uc may be said, 
so' n , ' as the instruments are concerned, in Meteorology. 

meteorological observations of most import- 



'I 1- J - i* ! Oi o C! ' ' i 



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PREFACE. 



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UiltEi w*.* 



ui arc esBentially of. 



ance which require instriimenta 
some delicacy^ and if not executed with a certain preci- 
sion and nicety, had much better not be recorded at all. 
But in both thcBe cases pa: ticular care has been taken 



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to make the instnictions for the use of the necessary 
infc^trumeots so nlain and full- that no diffieultv can be 
experic*^"''^'i by any one in acquiring from thenis witii a 



nagcment. 



little pracucc, their perfect mar 

The time apparently contemplated in the Memorandum 
for the completion and appearance of the work has be a 



exceeded. The delay, however 



1,. 






^ 




A:»^!CJ 



been inevitable 



One only of the contributors was aware^ until nearly a 






month sub^^'^^^^ent to t^^^ date of that document, of what 
was required of him ; and the various professional and 
scientific engagements of almost all^ precluded the possi- 
bility of their complying on the instant with the request. 
The Editor in particular must plead guilty to having 



been the latest in the field. The subject of Meteorology, 

intended for a far more able hand, devolved 



originally 



upon him, in consequence of the inability from illness, 
and supervening ^-lost pre-^^-ing engagements^ of the party 



in question to ndcrtake it- His own hands were uiher 



liSff 



vdse full : and he is but too conscious that, although 
written three or four times over^ his contribatlon fells 
very far short indeed of whv^t would have occrp^ed its 



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f -^ A JL 



PKEFACE. 



place had the original cast of the subject in this respect 
been carried out.* 

One otjiy of the chapters — that on Ethnology — has not 
received its final touches and corrections from the hand 
of its author. The eminent and gifted contributor of 
that chapter ^ irvived only to complete the MS. The 
correction of the press devolved on his son. Previous to 
his decease the Editor had received his authority for 

r 

substituting, as an appendix, a somewhat more extended 



(though still coniessedly incomplete) attempt of his own 



to facilitate the reduction to writing of foreign native 

for a system which, on maturely weighing it, 




m^ ^^es 



Ian 



appeared liable to serious objections. The subject is 
confessedly diificult : and it would have been peculiarly 
gratifying to him to have been enabled to submit tl/un 
aitempt to Dr. Pritchard for revision^ and to have received 

more than the general sanction above alluded to for its 
substitution. 



^iih the publication of this work the Editors con- 




* In more particular allusion to t^^s chapter the Editor would observe, 
that though the syixipiesometcr, and that substitute for the portable 
bare: _:..: to which the name of " aneroid" ha- been given, are not 
mentioned among tfie st-^dard and e? lUial meteorological instruments 
whose continuous registry is recommended; yet they may be consulted 
with ad^... tage, and frequent comparisons of the latter M'ith the baro- 
meter would be very nl in determining how far its indications at 
di: " ut times and in different circum.unees can be relied on. 



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PKKFACE. 



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nexion with it ceases, beyond a g:eiieral and earnest 



c 



interest in its succood in fo^ ./arul^ig tlie objects prop^ d 
by it ObseivatioDB ir-^'k in any of its dcpartojcnt?, in 



pursuance of the recommendations conta 



s conrainea 



i-.i 



% by 

oiSeersin Her Majesty's service, if officially comiiiunicated 
in the propter quarter, will of course be dealt with offi- 
cially. But as the work may^ and probably w^il, fell iu; j 
the hands of vov^^sers and traveller- unconnectud with the 






public service^ it may be right to bi^^e^ for tLt: avoidance 



of pos^r^We misapprehension, that he cannot charge him 
self with the reception, examination, or discussion of ..r 
masses of observations they may accun. ^-^'tr-. 



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HYDEOGR 

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GEOLuuY 






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XI 






1 



CONTENTS. 



MEMORANDUM by Lords Commissiokees or the Admikalx^ 



Pheface , , . 



« & 



* « « 



By the Editok . . • . 



6 » • 



Pag 



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5 « 



111 



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ASTRONOMY . 

Api£ndix 



« » « 



e # 



. . G. B. Atky. Esq. . 
. - By the Editob « • 



« » 



« • ■* » 4 



« # 



1 

11 



MAGNETISM 

!■ Appendix 



* I' it.-Col. SabinEj R.A. 



s p e 



« 9 



14 



* ' * OO 



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V 

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I 



HYDEOGRAPHY . , 

Appendix . . , . 



TIDES . 



« 4 



GEOGRAPHY , 



GEOLOGY 



© * 



• e 



EARTHQUAKES 
MINERALOG> 



Appenbix . 



> ft 



# c 



Cap't. Bj-echey, R,N. . . , , , 



as* 



« « 



• • 



«••»*» 



• • * Rev. Dr. WnEWKLr. , . , , 



a * • 9 



. . "W. J. H AMIJLTON5 Esq. , , 



. . . CiZAriLEs Dabw^in, Esq. 



o 9 



* a * 



••*?•£ 



, R. MalleTj Esq 



Sir H. T. De la Beche 



S f 



« « 9 



MPTEOROLOGY Sir J. F. W. Hekschei., Bart. . 



f- « • 



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* • 



ff a 



• « * * 



ATMO?^^'IIERIC WAVES 



^ e • • 



ZOOLOGY . 



V 



W, R. BiRT, Esq. 
Richard Owea, Esq. . , . 



V £r 



^ V 



BOTANY SirW. IIookER 



» A 



• * > 9 



Appendix 



*••»•# 



» » * 



ETHNOLOGY .._.,. Dr.- Fhitcharb 



ApPiJNDIX. 



a • ,* 



• iJy the Eottou 



* c J ^ * a 



* • • * 



MEDICINE and MEDICAL) 



STATISTICS 



c • « 



« « 



> Dr. Bryson 



STATISTICS . . . 



* » 



Appenj^»!X . 



# a * 



* a 



« 9 9 « 



• • * . 



- G. R. PoKTEBj Esq. , 



» « • « 



4 



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127 
155 
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A V A L 



OFFICER'S 




A N U A L . 



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Section I. 



A S T R O N O M Y. 



BY G. R AIRY, ESQ., 

ASTK0N05IER ROYAL. 



The science of Astronomy may occasiorially derive benefit 
from the observati ons of naYis;ators in the fbl lowiii<j 



respects : 



By contributions to Astronomy in general. 

By ImproYcment of the methods of Nautical Astro 



nomy 



* 



By accurate attention to Aritronomical Geography 



ri> 



rhe remarks which follow will be arranged under these 



i leads. 



General Adronormj, 






L The first point which calls for attention is the ob- 
^^r-^^tion of the places of comets or other extraordinary 
bo('ies, 'Specially those which can be seen only in low 
^^ >^^rn or in southern latitudes. In regard to these 
observations (and indeed to almost all others), one re- 
mark iMnnot be too strongly impressed on the observers : 
that a bad observation, or an observation which is given 

B 



2 



ASTRONOMY, 



[Sect. I 



10'^ 



ct. M 



'S 



without the means of verification, is worse than no ob> 
servation at all. In order to make the observations good, 
the following cautions must be observed :~ 

The index-error of the sextant must be carefully ascer- 
tained. If it has not been found a short time before the 
observations, it must be found as soon as possible after 

them. 

The distance of the comet from three conspicuous stai 

in different directions must be measured with the sextant. 
The point of the comet which is observed with the sextant 
ihould be precisely described. It is desirable that the 
navio-ator should be possessed of some star-maps or star- 
charts, bv means of which he will be able at once to give 
the proper names to the stars, and much confusion and 

loss of time will be avoided. 

If the time at the ship and the latitude are very well 

will be no occasion to make further observa- 



known, thei 



•e 



tions; but if these are not w^ell known, some attempt 
must be made (by the use of Becher's horizon, or by any 
equivalent method) to ascertain the altitude of the stars 
and the comet. The lower these objects are, the greater 
must be the care in the determination of their altitude. 
For affording means of verification, these rules should 

be followed : 

The observations of distance with the sextant should he 
entered in the book precisely in the manner in which they 






re made. The reading of the 




uncor 



reded. 



should be written down : in a column by the side of this 
should be written the correction for index-error, with a 
statement whether it is to be added to, or to be subtracted 
from, the sextant-reading : in the next column should he 



f 



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writtci 




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time, 
and, I 
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the 



er 



on G: 



must 
whicl 



1 



•At leii 
Watch 



K 



mine '^ 

All 
Adi 



Till 



2.( 



J 

i 



+ ■- 



:ncct. 1.3 



ASTRONOMY. 




^ * 



1 



t . 



♦ 1 



\ + 



¥ 



1 



41 



me 

k or 1. 
oft 



C 



a 



iv 



1 , 



1 '., 



1 



1 Hi 



i^ 



rr 
e 



cll 



1] 



n ri- 



written a reference to the observations by which the index- 
rror was determined : and in the last column should be 






written the distance as corrected. For the altitudes^ the 

the depression of the horizon, and the 



height of the 



V-- V v^ 



J ^^5 



altitude corrected for depression, should also be stated. 
At some convenient place, either at the beginning or at 
the end of all, should be written out all the measures bv 
which the index-error was ascertained, exactly in the 
manner in which they were made, and so that any other 
person can deduce from them the value of the index-error. 
The time of making every 



observation should 



be 

entered exactly as it is read from the chronometer or 
hack-watch. By the side of this should be placed the 
error of the chronometer or hack-watch on Greenwich 
time, or on time at the ship (as may be most convenient) 
and, after this, the corrected time. 



? 



At some convenient place, either at the beginninfr or 
the end, must be written out all the observations by which 
the error of the chronometer is ascertained. If its error 



on Greenwich time is given, the longitude of the ship 




must also be given, and the means and observations by 
which tliat longitude has been determined must be 
at length. 

If a hack-watch is used, the comparison of the hack- 
watch with the chronometer must be given. 

The last observations by v/hich the latitude was deter- 
mined, and the course and rate of sailing of the ship, 



must also b" 




jven. 



All the observations should be sent in this detail to the 
Admiralty or other body appointed to receive them. 
2. Opportunities will sometimes occur, when a ship is 



b2 



T^- - 









^ 

^ 



4 



ASTRONOMY. 



[Sect, I. 



I- 



:^cX' ^'^ 



^ 



s 



lying in a harbour of wiiicti the latitude and the longitude 
are well known, for observing eclipses of the sun. These 
observations arc almost always valuable. It can seldom 
be expected that the time of the begimung of an eclipse 
can be observed accurately, but the time of the end of it 

F 

can usually be observed with very groat accuracy. And 
if the eclipse is total, the times of beginning and end of 
the totality can be observed accurately: if it is annukr^ 
he times of beginning and end of the annularity can be 
accurately observed. The observation^i should be made 
with the largest telescope which the navigator pc^^esses ; 
and any peculiarity of distortion of the sun's limb or the 
moon's limb, siiy light surrounding the moon, &C-5 should 
be carefully recorded. [If the eclipse be total, attention 
should be paid to any coloured or other appendages pro- 

r 

iectino; from the dark edge of the moon, -'Iso to the 
luminous corona surrounding the moou, its apparent 

ivith the 



breadth, and whether apparently concentric 
moon or with the sun near the moments of beginning and 
end of the total obscuration.] While the eclipse is in 
progress, but especially near the beginning or the end, 
mca. v.res of the distance between the cusps or sharp points 
t which the moon's limb crosses the sun's hmb may be 
repeatedly taken. In recording these observations, the 






obseryatioiis by which the time is determined, and the 
observations bv which the index-error of the sextant is 
determined, should be written down in the fullest detad ; 



and the unreduced observations should be givuu as well 

as the reduced observations. 

3. In similar circumstances occultations of stars l)y the 
moon may frequently be observed. Eclipses of Jupiter s 



F 



f 



I 



I 









a 



Tid ^ 




"i 

^ 



oeii 



i 









Lto 




be rcv 

tioned 

4] 



W 



/here 



is DIUC 

these ] 
will tl 
atmos] 

observ 
limb I 
Will b( 
be ver 



al- 



so so 



there 
obse 



rvi 



utinoE;: 

5.1 

able oi 



a 



ni 



ble 



and j.^ 



stiite tj 

thf> 5 



or( 



Ml fV 



■** -: - . 



I.') 



Sect. I.] 



ASTRONOMY. 



5 



^ 



^ 



' 1 



"* k 



* * V I \_. 



\' 



1 



I 



i 

i 4 



■*-'i 



A *■ 



1 : 



^ 1 






*! 



y- 



J -■ . 



t 



■1 

1 inV. 



1 .V til 



Nl 



satellites may also be seen ; and (if the navigator have a 
teler^cope somewhat better than is usually carried in ships^ 
and steo "^ily mounted) the passage of Jupiter's satellites, 
either behind the planet or in front of the planet, may be 
seen, and the times at which the centres of the satellites 
just touch the edge of the planet may be observed, Al] 
these observations will be useful : the observation^^ must 
be recorded wic^i the same fulness wdiicb. has been men- 
tioned before. 

4 It may chance that the navigator is in some climates 
where the air is much more damp, and in others where it 






^\j.-M-i 



is much more dry, than in Europe. It is possible that in 

these places he-may be able to make observations which 

will throw some light upon the influence" of moisture in 

atmosj)heric refraction. It is recommended that repeated 

observations of the altitude of the sun s upper and lower 

limb be taken when the sun is very near the horizon. It 

will be necessary that the time at the ship and the latitude 

be very well known. Tlie thermometer must be read, as 

also some hygrometrical instrument, and the barometer, if 
there is 



"-■ - - 1 



one on board, during the observations. 



The 

observations of every kind must be recorded witii the 
utmost fulness. 

5. It IS certain that some of tlie stars of the southern 
hemiophere are var^-^^le in magnitude ; the most remark- 
able of these is n Argus. It is desirable that, on farour- 
abie nights, the magnitude of this star should be ob" '-ved 
and recorded. The best way of doing it will be, not to 
state that it looks like a star of the 2nd magnitude, or of 



the 



gnitud 



with that of some of the stars near it. Thus it wilJ be 



6 



rr^ 



ROKOMY 



[Sect. I. 



S 



ect. ^-^ 



easy to say that it appears pretty exactly as bright as one 
star, certainly brigliter than a second, and certainly not so 



tvtrl * 



bright as a third. 

6. Much atteBtion has been excited by the appearance, 
in several years, of meteors in great niunbers, on or about 
the 9th of August and the 12th of November.f It is 
probable that these appearances may be seen by per.^ons 
at sea, when, either from the hour at which they occur, or 
from other causes not yet understood, they cannot be seen 
in Europe. It is impossible to observe them with accu- 



but very valuable information will be given by 



racv 



counting repeatedly how many can be seen in some hxed 



interval of time, as five minutes ; and by remarking whe- 
ther they all come from, or go to. one part of the heavens ; 
what is that part of the hea>jns; whether they usually 
leave trains behind them ; what is their usual brightness 
(as compared with that of known stars) ; and by any other 
remarks which may be suggested by their appearance. 

7. Maay opportunities will occur of observing the zo- 
diacal light : more especially when the observer is near 
the equator^ where probably it can be seen at all seasons, 
before sunrise and after sunset ; or, if in northern latitudes, 
after sunset in February and March, and before sunrise 
in September and October ; if in southern lati^'^ides, bc^jre 



* c^. 



rfee a list of variable stars, and some suggestions for observations 






of bi igbtiiess of starsj in the Appendix. — (Eb. 

t Humboldt (Kosmos, i. 387) enumerates the following epochs as 

-26: Aug. 9-— 11; 



25: July 17 



especially fertile in meteors, viz. April 22 

Nov. 12—14 and 27—29: Dec. 6—12. Of all these epochs, that of 
August ha?. ^^Itherto proved to be the most regular. The star B Came- 
lopardali has for several years been their point of divergence about 



that epoch. 



Any cr -ige in this respect should be recorded 



(Ei>0 






sunrJ 



ail 







the su 



from 
cliiied 



\ 



^n^ 



lipt 



body c 
and th 
u-anot 

the. Jo 
naked 



-'^ 



IS 






should 
the St "^ 
with !■, 
jf tho 
the) 
the li 



lOJ 



1 



vations 
the ey 

registe 
to be 



St 



tatem 
weat] 



^"uuti( 






±^ 



r * 



'( 



t 



I 



-- A.' 



■- 1j 



'■ w* 



1 




<*** 



vli 



J 



' •' - 



^'jl^' 






} 



I 



Sect. I.] 



ASTRO>JOMY. 



7 



sunrise in March and April, and after sunset in August 
and September. The zodiacal light cc:: cists of a pyramid 
of faint liglit, wliose base is somewhere near tlie place of 
the sun, and whose point is at a distance of perhaps oOf 
from the sun ; the axis of the pyramid being usually in- 
chned to the horizon, following nearly the direction of the 
ecliptic. Although it presents to the eye a considerable 
body of light, yet the light of any portion of it is so feeble, 
and the definition of its outline is so imperfect, that it 
cannot be obsc. ,od w^ith a telescope. The observer. 



therefore, should only attempt to observe it with 



the 



naked eye, when the sky is very clear, and when the sun 
is so far below the hori?:on that no twilight is visible. He 
should then endeavour, with the assistance of a chart of 
the star'!', to define as accurately as possible its boandary 
with reference to the stars ; remarking especially the place 
jf the point of the pyramid, the width where it rise- from 
the hori zon, whether its sides are curved, and in what parts 
the light is brightest. It will be found that these obser- 
vations are made most accurately by occasionally turning 
the eye a little obliquely from the zodiacal light. In 
registering the observation, in addition to the particulars 



*^ 



to be recorded as prescribed abovOj there should be a 
statement of the latitude of the ship5 the day, the time at 
the ship (or the Greenwich tiiue and the longitude of the 
ship), the state of clearness of the sky, and the state of the 
M^eather for the day preceding the observation. 



Imp7wement of Nojjtical Astronomy. 

8. So much attention has been given to every detail of 
Nautical Astronomy, that it is very difficult to fix upon 



i> 



8 



ASTRONOMY. 



[Sect. L 



i 



■f^ 



.!■] 



' F^ 



any part of it to wlilch the attention of navigators sliould 
be specially directed with a view to its improvement. 



Pe 



rhaps the principal deficiency at the present time is in 
the want of weli-unilerstood methods of observing (with 
the sextant) the altitudes of stars at night, and of observ- 



ing the altitudes of the sun and moon when the horizon is 
ill'definede Every endeavour ought to be made to become 
familiar with the use of BecherV horizon, or some equi- 
valent instrument, and to acquire a correct estimate of the 
degree of confidence which can be placed in the use of it. 
9. It is likewise desirable that efforts should be made 
to facilitate the observation of occultations of stars by the 
mooo, and the observation of eclipses of Jupiter s satellites 



at sea. O 



but the result whic! 



I 



they give for longitude is usually so much more accurate 
tlian that given by lunar distances, that, in long vovages 



where little dependence can be placed on the chronometer, 

n occultation must be extremely 



the observation 






valuable. The eclipses of Jupiter's satellites afford less 
accurate determinations of longitude^ but they occur very 
much more frequently, and may be very useful where 
chronometers cannot be trusted.* 



* Attemptf. may laudably be made to deyise some available mode of 
suspending a chair, :^o as to afford a steady seat to the observer. Hitherto 
such attempts have failed of practical success, from setting out with the 
principle of perfectly free suspension, a principle -^hich tcnd6 to prolong 
and perpetuate oscillations once impressed. It remains to be seen what 
stiff suspensioii, as for example by a rigid rop^ or cable, or by a hook's 
joint, purpose'.^. iix:.C.^ to work stiffly (and that more or less at pleasure), 
by tightening collars — as also deadening and shortening oscillations, by 
iatf-ral cords passing through m/.7i- to create friction — and other similar 
contrivances may do. In the suepeasioa of a cot> at leastj I have found 
this principle signally available.— (Ed. 1 



10. 



1 



w 



■hichb 



very ^e 
deteritt) 

avul Ion 
mined 

laiitttd^ 
etood 



11! 



r raoi 



ih? . 







V^ 



to the 
the noi 

altitiidt 

is \isi^^' 

the N: 
tioiiB tb 
trough 

longlfu( 
Hmar d 
if th,. sc 



im 



1 



^f\-^^. 



f-^ 



ffloon 



c; 



mstriiia 



S^ 



lie 



m. 



and til 



§ 



^ . 



Sect. I.] 



ASTRONOMY, 







^^ 



1 



-nf 



X^'' 



f 

> 



» . ¥ 



ddronomical Geography. 



10. The intelUsent navio;ator. on arriving at any port 
wliicli has not before been visited, or whose position is not 
very well settled, ought to consider it his first duty to 



determine with all the accuracy in his power tiie latitude 
and longitude of the port. Supposing him to have deter 
mined by the usual nautical methods the approximate 

r 

latitude, longitude, and error of chronometer, the best 
metliod of determining the latitude will be to find the 
chronometer-time at which the sun or any bright stars of 
the Nautical Almanack hst will pass the meridian, and to 
observe the double altitude of any such object by reflection 
in a mercurial horizon, several times, as near as possibh? 



to the time of the meridian passage. If the place is in 



the northern hemisphere, the observation of the double 
altitude of the pole-star may be made at any time when it 
is visible : convenient tables for the reduction are given iu 
the Nautical Almanack. For these and other observa- 
tions the navigator ought to be provided with a proper 
trough and a store of mercury. For determining the 
longitude, there is probably no method superior to that of 
lunar distances (the exactness of which will be increased 
if the se2Llant or reflecting circle be mounted on a stand), 
unless the stay at the port is so long that transits of the 
moon can be observed. In any case, if there be a transit- 
instrument in the ship, it ought to be mounted on shore a 
soon as possible. The instrument ought, on the first 






evening, to be got very nearly into a meridional position, 



and then a mark should be set up, and the instrument 
hould always be adjusted to that same mark (even 



B 



^ 



^-j'^X 



- ^1 



E^" 



10 



ASTRONOMY 



A 



[Sect, I, 



APP^ 



vs 



though it be not exactly in the meridian), and should 
always be levelled, before commencing a series of observa- 
tion?;. One or two stars at least, as near the pole as 
possible, shonld be observed every night, in addition to 
the Nautical Almanack stars necessary for chronometer- 
error, and the moon-culminating stars which are observed 
with the moon. The instrument should be reversed on 
alternate nights ; and, if possible, as many transits of the 



moon should be taken after the full moon as before the 
full moon. 

In the register of all these observations, the same rule 
should be followed which is laid down under the first 




; that every observation should be recorded 
unreduced., exactly in the state in which it is read from 



th 






xtant or chronometer; and that the unreduced 



observations should b 



»e a 



ccompanied with the elements of 
reduction of whatever kind ; and that (if the navigator has 
[)ad leisure to reduce theia) the reduced results should 



also be ^iven. 




G. B. Airy. 



A 



jjiv V 



serv^^ 



t 




IS of 

order 



of 



rr 






^--. 



I 

1. 



f.- 



\ 



•■•Hi 



^st*-- 



J^ 



<Jl 



V-. 



u 



I, 



b.-T 



^n T 



Appendix.] 



ASTRONOMY 



11 



u 



ii 



APPENDIX 




BY THE ET>ITOR. 






\ 



(A, ) 

A List of the niost conspicuous Variable or Periodic Stars of "^ liieli ob- 
servatioiis would be desirable, with their periods of V^iriation (so f^ir 
as kuown) and changes of magnitude. 



! 



/5 Persei . 
I A. Tauri . 

B Cephei * 

p Lyrce . 
j ri Aquilse. • 
I Z Gemir.o" im 
! sc Herculis . 

' < Auriffse 
I A Leti 

i a Hydrsi 

\ ic Sagittarii . 

1 9j Argus . 

I fa Ursae Minoris 

I a&^jUrsaeMajorisl 



t 



I 



I 



Period 



I>. 



H. 

20 



48 



4 


i 


5 


8 37 


6 


9 .. 


*>* 

i 


4 15 


10 


o t-^<i) 


60 


6 .. 


1 9 months . 


334 


• s • • 


494 


. • 


Many 


vears . 


Irregular • | 


Unkn 


own . 


Do. . 


• • 1 



Change -'f 
Magnitude. 



2 
3-4 

3^4 

3 

3-4 

4-3 

3 



2 
4 
3 

1 






1'2 



to 

to 
to 

to 

to 
to 

to 



to 
to 
to 
to 
to 
to 



10 

6 



A 

■* 



2'3 
2 



4 
4 

4-5 
4'5 
4 



( B. ) 

Lists of Fixed Stars in either hemisphere, approximately arranged in 
order of brightness, down to the fourth magnitude, for the purpose 
of mutual comparison under fa-vourable circumstar.ces of altitude, and 
e ; :dally in equaf-^'TJ and tropical voyages, or land statLiis, with a 
view to bringing the nomenclature and scale of magnitudes in the two 
hemispheres to agreement, and to the improvement of this branch of 
astronomical knowledge. The comparisons to be made by the i . ' d 
eve amonor the stars of both lists not differing much (at the tiioe *jf 
observation) in altitude, and in the absence of the moon and twilight, 
and the results arranged in sequences, beginning with the brightest, 



^1 



12 



ASTRONOMY, 



[Sect. I. 



r 



. 4 



Ap^ 



and ending With the faintest star compared. In each sequence 5 to-s 
oftJie two lists should alternate tvhenever circumstances vnll allow 



o* 



v 



\'^ 



A returns. 
Capella, 
Lyra. 
ProcTon. 
c6 Ononis 

Aide bar an. 
« Aquilse, 
Poilu 

E.j^uius. 
f^ Cygni. 

Castor. 
t Ursge. 
a Ursse, 

a Persei. 

jS Tauri . 

y Orion is. 
Polaris, 

y Leonis. 

Z Ursa?, 

a Arieiis. 

/? Andromed^e. 

\uriira:. 

7 Andn*medai. 
7 Cassiopeiai. 
-% An drome doe, 
5c Cassiopeia, 
7 Geminorum, 
^ Leonis, 
■y Draconis, 
a Ophiuchi, 
/? Cassiopeia\ 
7 Cygni. 

5t Pegasi. 

2 P^^gasi, 
« Coroii,-r% 



i 
I 



I 



I 



a. Northern Stars. 



7 Ursm. 
/3 Ursae. 
£ Bootis. 

«Cephei, 
ft, Serpen tis. 
S Leonis. 



gni. 



« 



"» 




7 Aquilsc. 
I Cassiopeise. 
55 Draconis. 
/3 Draconis. 
/SArietis. 
7 Pegasi. 

t Virginis ? 
^ Aurlgie. 
,G Herculis. 

Cor Caroli. 
5 Ophiuchi. 

e Persei. 

J? Tauri. 
? Persei, 
c Herculis. 
z AurigjB. 
7 Urs^. Min. 
M Pegasi. 

5 Aquilte, 

6 Cya*ni. 

7 Persei. 

pi Trianguli B. 
3 Persei. 
£ AurigjB. 
r Lyncis, 
^Draconis. 
^Herculis* 



^ Canis Mhi. ? 
% Tauri, 
% Draconis. 

/A Geminorum. 

7 Bootis. 

£ Geminorum. 

3 Herculis. 

S Geminorum. 

q* Orionis. 

k Cephei. 

$ Ursa). 

i Ursse. 

« Aurigie. 

7 Lyrse. 

n Geminorum, 

7 Cephei. 

K Ursrc. 

s Cassiopeia^, 

^ Aquiia). 

S AndromedsD. 

»j Herculis. 

X Pegasi . 

5 Tauri. 
^ Cygni. 
a Trianguli B. 
^ Auri^"^. 
X Aquilaj. 
fA Herculis. 
i Draconis. 
^ Pegasi, 

X Draconis. 
vi Cassiopeia). 
$ Pegasi. 
Z, Cassiopeia^. 
5 Aquilte. 

fA. Herculis. 



Geminorum. 

X Geminorum. 
K Cephei. 

>? Cephei. 
Ursn^ ? 

X Geminorum. 
^ Geminonmi. 
Andromedfe. 
/3 Deiphini. 

X, Geniiuorum. 
« Deiphini. 
c Arietis. 

i Geminorum, 
X Tauri. 
Tauri. 
Tauri . 

Yi Piscium. 
/ Herculis. 
3 Bootis. 
7 Trianguli B. 

a Draconis. 
7 Tauri. 
7Ariotis. 
r Cygni. 
i Cephei. 
Herculis. 

Herculis. 
e Cygni. 

/ Pegasi. 

1 Pegasi. 
S Aurigse. 

7 Sagittal. 
7 Ophiuchi. 
ip Draconis. 
- TMphmi. 
a Piscium, 



\ 



5f 









J 



«f 









M^J- 



i^ ^ 71 r 



as. 



'n 



-^^ 



K/U 



5 Canis. 



TIC 






I Ar 



+ f 



nt' 



f'Cr*-- 



'* * * 



\ ^ 



i 

-F 



f 



^ 



f. 



j 

I- 



Appendix.] 



ASTRONOMY, 



1 



3 



b. Southern Stars. 



+r» I 



f^ * 



to 



■ . n 






U w- 



feiriiis. 

Canopus. 
a Centauri, 

ll5geL 
a Eridani, 
/S Centauri, 

a Crucis. 

An tares. 

Spica. 

Fomalhaut, 
fi Crucis, 
a Gruis. 
7 Crucis. 
B Orionis. 



£ ' 



r^ 






X Scorpii. 
t Orionis. 

/5 Argus. 
y Argus. 

I Argus. 
a Trianguli 
£ Sagittarii. 
^ Scorpii. 
cc Ilydrse, 
I Canis. 
« Pavonis. 
,5 Gruis. 
«/ Sagittarii- 

I Argus. 
iSCeti. 

X Argus. 

^Centauri. 



A 



/^Canis, 
^ Orionis. 
3 Orionis. 
7 Centaixri. 
2 Scorpii. 
2^ Argus. 
ct Phoenicis. 
! Argus. 

a Lupi. 

2 Centauri s 
f? Canis. 

/5 Aquarii, 
S Scorpii. 
>! Ophiuchi. 
y Corvi, 
*? Centauri. 
H Argus. 
fi Corvi. 
/3 Scornr 
^ Centauri. 
t Ophiuchi. 
C6 Aquarii. 
57* Argus. 
S Centauri. 
a Leporis, 
S Ophiuchi. 

5 Sagittarii. 

^ Ophiuchi. 
/3 Librre. 

7 Virginis, 
^ Argus. 

3 Sagittarii, 



I X Libras. 
I X Sagittarii. 

3 Lupi. 

a Columhry. 

I Centauri. 
S Capricorni, 
S Corvi. 
(^ Eridani, 
^ Argus, 
iS Hvdri, 
s Corvi. 
(^ Arce. 
a Toucani. 
iS Capricorni. 
p Argus* 
^Scorpii. 
/3 Leporis. 
y Lupi. 

V Scorpii, 
i Orionis, 

^Sagittarii. 
cc Muscse. 
as Hydri ? 
■T Scorpii. 

4 Hydrpe. 

y Hydri 

^ Trianguli A, 
a- Scorpii. 

r Argus. 
-j/Triang. A. 

r, Derpentis. 



JS 



'f». 



i scorpii, 
if Arguh;^ 
>- Crucis. 
y Sagittarii. 
V Hvdrse, 
^ CeDtauri. 
N Velorum. 
/3 Colunib-* 
^ Canis. 

7 Gruis, 
ex. Indi. 

|3 Muscce. 
X Centauri. 

7Tu])i. 
y Ilyuri. 
a> Argus. 

8 Hydras. 
B Eridani. 
y Argus. 

Argus. 
c'^ Canis. 
TT Hydrse. 
/3 Tubi. 
a. Pictoris, 
^' Sagittarii. 

(T Argus. 
io Doradu52. 

fo Phceuicis, 
§ Aq rii. 

^Scorpii. 



r- 
^ 



( 14 



[Sect. II. 



( 



^ 



Sect. 






Section IT. 



TE 




EESTEIAL MAGNETISM. 



BY LTEUT.-COLONEL EDWAIII) SABINE, 

or THE ROYAl. ARTILLERY. 



1. The magnetic observations which are at present 
raakiTJg by naval officers have for their object the deter- 
mination of the amount and direction of the Eartli^s mag- 
netic force in different parts of the globe. 

2. The amount of the magnetic force at any point of 
the Earth's sm^face may either be measured in ahsolntf^ 

m 

or its ratio may be ascertained to the value of the 
at another station where its absobate measure is 



value 
force 



9 



already known. 




means have vet been devised for 
measuring absolute values at sea ; consequently, all de- 
terminations of the magnetic force on board ships are 
necessarily of the relative class : these crive the ratio, or 



5 



proper lion, vvhich the force at the geographical position 
in which the ship is at the time when an observation is 
m^ade, bears to its value a^ some land station which is in- 
eluded in the same series of relative observations, but 
where an absolute determination has also been made. 
Ships are therefore supplied with instruments for both 
absolute and relative determinations ; the latter to be used 
at seaj and on land at times when the ship is in harbour; 
the former to be used exclusively on land. 



f 



r 
J 



r 



prac 

tion 

" tol 
that 

to tl 

pon( 

apr 

fice 

hori 

tlie 



I 



he 



a mi 

forci 

pro| 
iniir 

the 



pos 



s 



■■vei= 



Th 



f 



mer 
calc 

Th, 
net 

secf 
Tb. 



Sect. II.] 



TERRESTRIAL MAGNETISM. 



15 



If 



■ * , - 



i 

r- 



tW 



.^'. 1. 



1 



! 






I 

^ 



1 .-* 



i 






, ..I' . 



Absolute Measurement of the Maanetic Force. 



*- 



3. No satiBfactory method has yet been brouglit into 
practice for the direct absolute measurement in one opera- 
tion of the vjhole magnetic force of tlie Earth (called the 
^' total force'') at any particular point of its surface. But 
that portion of the force whicli acts in a direction parallel 
to the surface of the Earth (called the " horizontal com- 
ponent") may be measured with considerable accuracy by 
a process, of which the following brief description may suf- 
fice to give a general idea. If a magnet be suspended 
horizontally by a few fibres of silk, and made to vibrate in 
the horizontal plane on either side of its position of rest, 
the square of the number of vibrations in a given time is 
a measure of the horizontal component of the magnetic 
force of the Earth, but is also dependent on the individual 



^- 



SL- 



properties of the magnet employed. Inese properties 
influence the time of vibration in two respects : first, by 
the gr^r-^ter or less magnetic force which the magnet itself 
possesses ; and, secondly, by the effect which the form and 
weight of the magnet produce on the time of vibration. 
The latter effect may be eliminated wlien the moment of 



maemet 



T • 



L r 



-V e 



ither be 



calculated by known rules, or may be ascertained experi- 
mentally by vibrating the ma 




net 1^ in its usual state, and 



2^ with its momont of inertia increased by a known amount. 
The influence of the magnetic force possessed by the mag- 
net may also be eliminated by ascertaining its. magnetic 
moment. This is accomplished by using it to deflect a 
second magnet similarly suspended in another apparatus. 
The deflecting magnet is placed at one or more exactly 



I 



16 



TERRESTRIAL MAGNETlSiM. 



[Sect. II. 



measured distances from the centre of the suspended mag- 
net, and perpendicular to it. The deflections thus pro- 
duced, (/.^. the angular differences in the positions of rest 
of the suspended magnet. P when influenced solely hy the 



Earth's magnetism, and 2° when in equilibrium between 



the Earth's magnetism and that of the deflecting maoiiet 
at the distances employed,) furnish the ratio of the forces 
exerted respectively by the Earth's force and that of the 
magnet ; and as the p7-oduct of the same two forces is given 
by the vibrations of the deflecting magnet when suspended 
as in the experiments first described, the values of eitlier 
force may be separately ascertained. The influence of the 
magnetism of the magnet, and of its form and wei«.^lit, 
being thus elinslnated, a m.easure is finally obtained of the 
force of the Earth's magnetism, independent of the indi- 
vidual properties of the m.agnet employed in the deter- 
mination, 

4. Tlie numerical expression by which the measure of 
the Earth's force thus obtained is denoted, depends on the 
units of time, of 

siirements and calculation. In eonfurmitv with the In 
structions published under the authority of the Royal 
Society, a second of time, a foot of space, and a grain of 
mass, are the units so employed ; and the horizontal com- 
ponent of the Earth's magnetic force has been found, by 
the observations hitherto made, to vary at diflferent points 
of the Earth's surface from to about 8-4 of the scale 
founded on the units which have been specified. 

5. T^Hierever the horizontal component of the force has 

pertained in absolute measure, there also, if the 



s 



pace, and of mass employed in the mea 



been 






magnetic direction be known, the " total force" in abso- 



[ 



L 



( 



i 



I 



I 



1.7 ■ 



ct. 1 



lute 1 

callec 

the ol 
deter: 

taiiie^ 

corre: 
longii 

taken 



are vi 



expre 

refer] 

feren' 

hi the 

pruct 
rioiis 

(and 



was i 



} 



)V 



xY. 



sent 
dire 
tion 



( 



an i 



E 



art 



tioTi 



t- 

r 



f. 



r -i 



Sect. Ii.j 



TERRESTRIAL MAGNETISM. 



17 



\ ^ 



.]. 



J 4^ A 



, J 



>- - 



:! 






] 



A 






lute measure is determined; since it consists of the hori- 
zontal component multiplied by the secant of tlie angle 
which the macrnetic direction makes with the horizon. As 



ships are supplied with instruments by which this angle, 
called the dip or inclination of the needle, is measured, 
the observations on land, when the ship is in harbour, give 
determinations of the total force, which serve as base deter' 
minations, to which are referred the relative results ob 
tained at sea in the passage from one station of well- 
assured ahsolute determination to another; — a practice 



corresponding to that which prevails in determinations of 



longitude, where stations of w^ell-assured longitude are 
taken as hase stations, to which intermediate observations 
are referred. The total force of the Earth's magnetism, 
expressed in the scale in which the British units already 
referred to are employed, has been found to vary at dif- 
ferent points of the Earth's surface where observations liave 
hitherto been made, from about 6-4 to 15-8. Before the 



practice was adopted of determining absolute values, va 



r 



V 



r^* 



rious relative scales were employed, not always commen- 
surable with each other. The one most generally used 
(and which still continues to be very frequently referred to), 
was founded on the time of vibration of a magnet observed 



t- 



bvM 



H 



sent centurv, at a station in South America where the 
direction of tlie dipping-needle was horizontal ; a condi- 
tion which was for some time erroneously supposed to be 
an indication of the minimum of magnetic force at the 
Earth's surface. From a comparison of tlie times of vibra- 
tion of M. de Humboldt's mamet in South Am.erica and 



in Paris, the ratio of the magnetic force at Paris to what 



1 



J 



•1^ 



1 




TERRESTRIAL MAGNETISM. 



[S<ict. II. 



was supposed to he its minimum was inferred ; and from 
the result so ohtained^ combined with a similar compari- 
son made by myself between Paris and London in 1827 
with several magnets, the ratio of the force in London to 



M. do H 



rica 1 



>tant 



and thus to afford a secure unvarvinsj basis foi 



been inferred to be 1'372 to 1-000. This is the 
origin of tlie num^ber l'372j which has been generally em- 
ployed by British observers, not furnished with the means 
of making absolute determinations, to express the vnlue 
of the magnetic force at their base station, viz.j London. 
The essential disadvantage, ho. /ever, under which any re- 
lative scale of the nature referred to labours, is, that the 
magnetic force of the Earth has been found to be subject 
to secular variations, so that at no one spot on the surface 
of the globe can the intensity be assumed to remain con- 
such 

a scale ; whereas by absolute measurements, we are not 
oxdy enabled to compare numerically with one another the 
results of experim.ents made in the most distant parts of 
the globe, with apparatus not previously compared, but 
we also furnish the means of comparing hereafter the in- 
tensity which exists at the pre^^ent epoch, with that which 
may be found at future periods. It is probable from these 
and other considerations, that the employment of mere 
relative scales will shortly be entirely superseded by the 
general adoption of a scale in which the value of the force 
is expressed in terms of a fixed and unchanging unit. 

6. The instrument with which the absolute value of the 
horizontal component of the force is measured is called the 
Unifilar Magnetometer ; its description, and that of the 
process by which results are obtained with it, are given in 



f 



I 



q^t. 



II.] 



ipp 



e 



ntt 



horizon^ 

the tim^ 
rnent- 



Unt3, 



^ 



h< 



ijUii 



'UP : 



moment 

one deg 
rection 

iu y^^"" 

by iiidu 

for ead 

rainatio 

eonstaii 
wich b( 

officer ^ 



7.1 



de 



:tv,j ai 



positi 



mad 



e 



5 



m.ent 



ob^ 



ierv 







Sect. II.] 



TERRESTRIAL MAOXETISM, 



9 



^ i^ 



■14V 



\ 



V 



R 



» 



L 4 



{• 



,1 



i- 



J 



' i 



I 



. ;!,j 



Appendix No. 1. A tolerably practised obs.. ,er will 
ooraplete the procc^ss by which a measure of the absolute 




horizontal force is cl.tained in about two hours, includin 
the time required for setting up and adjusting tlie instru- 
ment. It is desirable that there should be at least five or 
six repetitions at places which are to serve as base stations ; 
nd also, as a spare rnagnet is always supplied, that both 
agnets should be employed. 



a 



There are certaii 



con- 



D 



otlrrup in which it rests, the change which the magnetic 
moment of the magnet undergoes from an alteration of 




one degree of temperature, and the coefficient in the cor- 
rection required for an increase of force which the magnet, 
in certain positions in which it may be used, r^ay receive 
bv hiduction from the earth,] which have to be determhied 
for each magnet once for all, and require for their deter- 
mination apparatus which is not afterwards needed : these 
constants have hitherto been usually determined at IVool- 
wich before the instrument is put into the hands of the 
officer who is to use it elsewhere. 



Relative Measurements of the Magn^Llc Force. 

7. These are the observations which are made at sea, to 
determine the ratio of the total force in the geographical 
position of the ship at the time when the observation is 
made, to ^^ value at some base station where the instru- 
nient has been landed and used in precisely sim.ilar 
observations to those made on board ship. The instru- 
ment is the well-known apparatus devised by Mr, Fox, 
which has contributed more to a knowledge of the geo- 




raphical distribution of terrestrial magnetism than any 



■j^ ^ 



f7. 



'. P 



i 




-tf 



:4 



^j 



^ 



20 



X 



ERRE::..RIAL MAGNETISM. 



[Sect, II. 



Other recent invexition. Trie following brief description 

'\ general idea of the apparatus and 



mav serve to give 



of the mode of obtaining results with it, more full 
directions for its use heing given in Appendix No. 2. It 
con?istR of a dipping-needle and gi-aduated circle, differ- 
ing little from the accustomed form of an Inclinometer 
except that the needle is supported by the ends of the 
axle, which terminate in cylinders of small diameter 
working in jewelled holes. A small grooved wheel is 



carried on the axle, and receives a thread of 



unspun silk, 



farnislied at each extremity with hooks to which small 
weights may be attached, for the purpose of deflecting- 
the needle from its position of rest in the magnetic direc- 
tion, and causing it to take up a new position, in whicli it 
is in equihbrium between the opposing forces of the 
Earth's magnetism and of the deflecting weight. The 



weight being constant, and the magnetism of the needle 
assumed to be so, the intensity of the Earth's magnetic 
fsjrce in different localities is inversely as the sines of the 

For'gTeater accuracy, several con- 



angles of deflection 

stant weights are employed on each occasion ; and each 



weight is successively attached to each of the two hc^Li, a 
mean being taken of the deflections on either side of the 

at sea is 



position of rest. 



The apparatus when 




placed on a giml):ul toble, by which the motion of the 
vessel is greatly counteracted : and when the weather does 
not permit the manipulation of the weigLL, deflecting 
magnets are 






bstituted, the operation of whicb may be 
understood from the detailed instrur^'ons in Appendix 



"^ J. X 



No. 2, A\'ith the gimball table as recently constructed, 
it is found that but very few days occur in which the 



I 



^ect. 1^'^ 




It. .13 li- 

observat 

as little 
tlie inst 
selectee' 

/hen tl 



/ 



£! ( 



result; 

tiii! t the 
of defiec 
onlv tn 
varied ; 



artists 



? 



gene^'^11 



i:.^OTeti 
desii^abl 



ao u 



ften 



and evi( 
of the 

Ae rela 
ha\^ 



to bas 
known. 



e 



oh ^ 



'^i. 



^t^ation^ 
referen 

determ 



■r 
J 



'j 



k . 



Sect. II.] 



TERRESTRIAL MAG:%ETISM. 



21 



i ' 



i 



....g 



angles of deflection, cither with weights or deflectors. 
cannot be satisfactorily ascertained by a careful observvi. 
It iS necessary that a spot should be selected for the 
observations to be made on board ship, which should have 
as little iron as possible within 5 or 6 feet of it ; and that 
the instrnraent should always be us^d in the spot so 
selected. The mode of investigating and of eliminatin 
(when these precautions are raken) the influence on the 
results of the iron contained in the ship is explained in 
Appendix No. 4* It must be carefully borne in mind, 
that the inverse proportionality of the sines of the angles 
of deflection to the variations of the eartl 
onlv true when the magnetism of the needle has not 
varied ; and althijugh the needles made by Falmouth 
artists, under Mr. Fox's own superintendence, have 



1 B magnetism, is 



generally proved most remarkable in preserving their 



magnetism unchanged for years and in all climates, it is 
desirable that reference to a base station should be made 
as often and with as short intervals as may be cxmvenient ; 
and evidence must always be furnished that the magnetism 
of the needle has not changed in a certain iiiterval, before 
the relative determinations made during that interval can 
have weight. The more frequently references are made 
to base stations at which the value of the magnetic force is 
known, the less damper exists that the labour bestowed on 



observations at sea will pro . . anproductive ; and the more 
stations are multiplied which afford opportunities of such 



reference, the greater become the facilities for accurate 
determinations at sea. 



k- - 






1 *; 



22 



TERRESTR I AL MAGNETISM. 



[Sect. II. 



Direction of the EartJts Magnetic Force. 

8. The direction of tlie Eui'th's magnetic force under- 
goes every possible variation at diiFerent parts of tlie 
Earth's surface. For ihe purpose of determining am] re- 
presenting this direction, it has long been customary to 
refer it to two planes — the horizontal and the vertical 
planes— and to take the geographical north as the zero 
of the horizontal plane^ and the horizontal Hne us the 



zero of the vertical plane, 



m 



( 



.* 
"^ 






as it is more usually called by naval men) is the angular 
difterenccj measured on the horizontal plane, between the 
direction of the north end of a magnet or needle and the 
geographical north point ; and the inclination (or dip^ as 
it is frequently called) is the angular difference, measured 
on the vertical plane, between the direction of the same 
north end of a magnet or needle and the horizontal zero 
point. (The north end of a magnet here spoken of is that 
end which in Europe points towards the north, and dips 
below the horizon.) Tlie declination is called West, if 
the direction of the north end of the magnet or needle is 



to the west 



SfcoOTanhical 



reckoned 



from 0" to 180% passing from North through West to 
South. In like manner, the declination is called East, if 
the direction of the north end of the needle is to the east 
of the geographical north, and is reckoned from 0^ to 



180% passing from North through East to South, The 



positive and neoative signs are also sometimes applied 



instead of the terms West and East, in which case + sig- 
nifies West, and — East Declination. 

The Inclination is counted positive, or has the sign 






\ 



\ 



\ 



! 



I 



I 
J 









gect. 



II.] 



US pi 



•e 



,.Sn^ 



tl 



f 



inclines 



s 




pi-^ of 
beluvv t 



equiva 



1 



P 



9. Tl 



, , dii 



requ 



ire 



' -^ 



now mac 

R.N., a 

for the 



tl).e 



prac 



tainin 
of 




a 



Shi| 

leave lit 
which 



I 



^miliar 



ar*^ 



give 



10.- 

fervatic 
intensi 



b 



Sit 



^ ^ocaj 



■4. 

■■4 



■>x+- - 



I - 



— ■ H* 



i ^ 



4 



i 
t 



]' 



r 



Sect, 11.] 



TERRESTRIAL MAGNETISM. 



no 




US prefixed, when the north end of the needle inclines 
below the liorizon ; and is counted negative, or has the 
minus sign prefixed, wlien the north end of the needle 
inclines above the horizon, Sometiints, instead of the 
signs + and — , the term 



C 

o 



s 



1 are used 



•) 



D 



ep 



A 



o • 



IS 



of the needle dips below the lionzori, and South In 
clination or Dip is when the south end of the needle dip 
below the horizon. Thus an Inclination of — 30 
equivalent to 30° South Dip. 

9, The Declination is measured by the azinuith com- 
pass, an iDstrument too well known to naval officers to 
require any 'ascription here, or any directions for tlie 
niethv)d of observing with it either on land or at sea. As 
now made, under the superintendence of Captain Johnson. 
R.N., and on the plan recommended by tlie Committee 
for the Improvement of Ships' Compasses, the azimuth 
compa£: in the hands of a careful observer, attentive to 
tlie practical rules published by the Admiralty for ascer- 



taining the deviations of the compa/-" caused by the iron 
of a ship, will give results, both at sea and on land^ which 
leave little to be desired. The use of the dipping needle, 
which measures the inclination, not being so generally 
familiar to naval officers, full directions for its employment 
are eiven in Annendix No. 3. 



Local Attraction. 
10. It has been found that the results of maimetic 



servations, whether of the declination, inclination, or of the 
intensity of the magnetic force, are liable to be influenced 
by local attraction proceeding from the rocks or soil in the 



24 



TERIIESTRIAL MAGNETISM. 



[Sect. II. 



vicinity of the instrument, and particularly so at stcitions 
where the rocks are of igneous character, such as traps, 
basalts, granites, &c. As a precautionary measure, ther.. 
U raagnetical instruments should always he used on 



fore 



stands which raise them 3 or 4 feet above the ground ; 
and those stations are to he preferred of which the <>eo- 
logical character is sedimentary or alluvial. Stations of 
igneous character, though less eligible for obtaining results 
which show the correct magnetical elements corresponding^ 
to the geographical position of the station, may nevertlie- 

be serviceable as stations of comparison between the 






IS essen- 



land and sea instruments ; but for this purpose it 

tial that the different instruments to be compared should 



1 



.*v V 



be used precisely on one and the same spot, in wdueh cu.. 
the local attraction may be supposed to be a constant 
quantity. And if the station be one frequently resorted 
to by vessels from which magnetic observations are made, 
it is desirable that tlie spot should be suscepti'^^e of a 
definite and well-recognisable description. 

At sea, from the quantity of iron which a ship contains, 
it is scarcely possible that its influence on the instruments 
should be altogether avoided ; but from the circumstance 
the' the greater part of the most influential iron is in 
fixed positions in the ship, it has been proved by sufficient 
experience, that by a proper selection of the place in 
vihich a magnetic instrument is used on board ship, and 
by a certain process of observation (repeated whejiever 
the ship has undergone any consideriible changes of geo- 
graphical position), the influence of her iron is susceptible 
of a sufficiently annroximate calculation, and ot uemg 



'7 ap 



eliminated accordini>i 



w^-y* 






Sect 



111 



The ii^f 

this f^^' 
If .houia be 



it- 



5m' 



11, An 

iietlc obserr; 
Ills sliip- has 



take care 



th 



tbe sljip is 
himself that 
jicrienced ii 
id' - may 
^'■, >al' tlieii 

tbi instrume^ 

auaoestatic:: 
relati\e d 

fertile g*-^ -■* 
^" pilar fbr ■ 

^tions 



ii 



I 



-^<^ (Or 



I 



/ "^ Ton of t 

^"i Pen . 
^% or at 1 

^ Vt„, , 



*1 






I, 



" If „ 



t- 



M 



, »i 



T . 



»A 



\4 



t^^ 



01! 



ftff : 



V 



^* 



in 



T yt *- 



■^O*'' ."■.. 



% -.^ _ 



yn.., 



w 



m ; 



.*o a 



nrt 



J ' 



31- ' 



: t*A 1 



> • 



.. « 



. /.•.' 



Iv 



liii. i 



ru 



T' 



it 



.f.^' 



1 



/ 



Sect. II.] 



TERRESTRIAL MAGNETISM 



2^ 



?/ 



The importance^ and in some degree the noveltyj of 
this part of the subject has made it appear desirable that 



No 



Summary of the Observations to he made. 



11, An officer, therefore, who pm-poses to make mag- 
netic observations, or to cause them to be made on board 
his ship, has to attend to the following points :™™He must 
take care that he obtains the instruments some days before 
the ship is ready for sea, in order that he 



mav assure 



himself that they are all complete, and that, if inex- 



perienced in their use, he, or the observer 



whom he 



selects, 



may have some preliminary practice with them. 
lie will then have to determine the constants, index cor- 
rections, &c. (unless these »hall have been furnished with 
the instruments), and to make the observations required for 
a base station, with the needles which are to be em.ployed in 
the relative determinations of the magnetic force and dip 
at sea. Positions will then have to be selected on board 
for the standard compass, and for Fox's apparatus, and 
tlie pillar for the one, and the gimball stand for the other, 
fitted accordingly. When the ship is ready for sea, the 
observations which are directed in the Admiralty Instruc- 
tions for ascertaining the deviations of the compass caused 
by the iron of the ship are to be made on board ; and when 
the ship is swung round for this purpose, the deviations 
of the dip and of the force must be also observed, on the 
sixteen, or at least on the eight, principal points of the com- 
pass, with Fox's apparatus used at the spot selected for it. 
This completes the preparations to be made before trie 



^^ 



c 









^ 



?6 



TERRESTRIAL MAGNETISM. 



[Sect. II. 



and intensity described in 



No 



as well as 



those of the variation by the standard compass, should be 
made daily, whenever the weather and other circumstances 
permit. Whenever the ship is in harbour, and time and 
opportunities -^re suitable, it is desirable that the instru- 
ments should be taken on shore, to a spot selectt;d as least 
likely to be influenced by any local attraction : and that 
the declination, inclination, and absolute horizontal force 

^ 

should there be determined, and the comparative observa- 
tions made with Fox's apparatus. If the ship has ma- 
terially changed her geographical position since the last 
occasion when the deviations vvere ascertained, or if changes 
have been made in her equipment by which the deviations 

have been affected, it is desirable tliat the procc::. 



mav 



fr 



>Y their examination should be repeated ; and lastly, the 
hnrbour observations here described should not fail to be 
repeated whenever the ship finally returns to England. 



Record and Transmission of the Observations. 

12. Blank forms are supplied for the entry of observa- 
tions of all classes, and for the first or uncorrected cal- 
culation of those which require that process to be gone 
through at the time. It is desirable that the forms should 
be filled up in duplicate, and that one copy should be 
retained, and the other sent to England from time to 

On 

their arrival they should be immediately examined, and 
any suggestion to which they may give rise communicated 
at once to the observer.* 



time, as 



soon a 



circumstances make it convenient. 



* T^i,; 



i iiis has liithcrte been done on all occasions when practicable, and 
it is very d--!rablc- that it should always continue to be done. 



i 



!-;ect. U 



13. 



\h-' 



mag^^ 



form i 
maps, 

of ^'^^ 



c 



T 



v^ t> W V ^ 



t 




\J 



Hue? " 
force, 1 



_ 1 



IL 



■*■; 



>1 



W»^ 



** 



pjin'^*^-.-^ 



t'T-T r^ ,,, 






^ . 






) 1 



1 



■i^^ 



n 



^4 



"'V 



toi 



T) 



to 









a.^ 







■ -'U \, 



> >^1' 



^ 



t ' 



\ 



•1 



V. 



} 



:t . 



T=--^i^H 



r\r 






le 



fV 



til . 



^ 'T 



T^nnr].' 



u 



^V 



r Oi 



to 



1^ . 




i**' 



>r 









aii5 



.-I 



i 



J 



Sect. II.] 



TEREESTKIAL MAGNETIi^M. 



27 



Application of the Mesult^. 

13, The observations when thus received require that 
the several corrections arising from the influence of the 
I m^ the variations of temperaturej the changes in the 
magnetic force of the magnets, and from various other 
sources, should be sought out, computed and applied 
and the true or corrected results finally derived. Thes 



5 



-e 



form the materials from which it is intended to construct 



maps, showing tlie variations 



o 



magne 



o 



and 



of the magne 



clination 



and declination, corresponding to the present 



epocii 



^\ over the whole surface of the y;lobe. 



& 



The 



varia- 



tions of the three elements are shown on these maps, by 
lines comiecting, for example, in the maps of the magnetic 
force, those points, where the intensity is observed to be 
the same ; — in the maps of the inclination, those points 
where the inclination is observed to be the same ;— and in 
the maps of the declination, those points vvhere the de- 
clination is observed to be the same. These lines are 
known by the names of Isodynamic, isoclinal, and Iso- 
genic lines. The Isogenic lines, which form the maps of 
the declination (or variation charts), have a direct practi- 
cal importance and value in navigation, %vhich in a notice 
addressed to naval officers needs not to be dwelt on. In 
theoretical respects, the Isodynamic and Isoclinal lines 



are not less essential ; the three form the basis of a svste- 
matic view of terrestrial magnetism, as it manifests itself 
to us on the surface of the globe. 

The mode in which the results are made to contribute 



_^ r 



to the formation of these maps is the following 

c2 



Th- 



^^±rf-> 



28 



TER RESTRl AL MAG NE TISM. 



[Sect. II 



results of the three eleaients finally corrected are entered 
each m its proper geographical position, on maps on a 
large scale, severally appropriated to the force, the in- 
clination, and the declination. Each result has a small 
characteristic mark denoting the ohservcr. Wlien ain 



portion of the globe is sufficiently covered hy the results 



of observations in proper distribution, the isopheenomena] 
lines are drawn for that portion of the globe in eorre- 
spondence with the observations, with a free hand, but with 
a careful judgment, aided occasionally by a process of 
calculation Vvhich it is not necessary here to describe. 
From, those maps tables of double entry are formed, 
having tlie latitude at the side, and the longitude along 
the top of the page, and the values of the magnetic ele- 
merits corrosponciing to the several latitudes and longi- 
tudes are placed at the points of inLersection. By proper 
car;- m tiie process, the step of iornung the tables from the 
maps need involve no additional uncertainty whatsoever. 

M 



iB thus prepared will, when completed, 
form an experimental theory of terrestrial magnetism, 
in which the facts of nature will he shown with greater 

Sj in proportion as the observations are 



or less 



tne 



numerous, correct, and suitably distributed, and as they 



i 



are more or less corroctly represented in the maps. 
Mathematical formula, based on general mathematical 
views, having uuniorical coeificients of which the values 
are derived from these maps, m.ay also serve for the com- 



gnetic elements at any geographical 



position on the surface of the globe ; and if the points 
taken from the maps to serve as the basis of the numeri- 
r*al valueB of the coefficients are sufficiently numerou 



Sj 



Sect. 



I 



a 



r 



iidi 

lobe 



ber c 



) 



cowp 






It 

prosp 
Tiiagri 
a nio 
liaps 
the SI 



rr 



chici 



assidi 



mi 



irh 



Admi 
appoi 

expre 

upon 

comrD 

parts 

-Of 
ded 
the e 

h th> 

of of] 



UC 



ai 






tho 



V-- 



eni 



s 



to 



> Vj, 



piet- ^ 



s 



Sect II.] 



TERRESTIIIAL MAGNEi 



2y 






> 



I v% ^ 



B. 



L ■ 



t 



1^ 



. hJ ' 



i . 



and have a i^roper distribution over the surface of the 
globe, and if the formulae are carried to a sutrkMent num- 
ber of terms, it may be expected that the elements 
comnuted from them will have the same degree of exact- 



ness as the maps i, jm which their coefficients are taken. 



It 



may 



be natural 






this stane to inquiri; 






prospect exists of being able to complete a work of this 



magnitude within a reasonable time 



ct 



; and to this question 
more satisfactory reply can be returned than may per- 
haps be generally anticipated. Nearly three-fourths of 
the surface of the globe being covered by the ocean, it is 
chiefly by naval surveys that the materials for sucli a, 
work can be collected. By the zealous and unwearying 
assiduity of British officers, acting under the sanction and 
^- the approval of the Lords Commissioners of th 



wirn 



e 



Admiralty, and in some instances in expeditions specially 
a])pointed for the purpose, magnetic observations designed 
expressly for the object above-mentioned, and conducted 



■ 
-ft- 



upon a uniform system, ha\e been extended, since theii 
commencement in 1839^ over nearly all the accessible 
parts of the ocean. 

Of these surveys, the results of some have been already 
deduced and published in the Philosophical Transactions, 
the expense of publication having been borne conjointly 
by the Government and by the Royal Society ; the results 



of others are undergoing the process of calculation and 



arrringement for publication ; and in a third class, more 
.:...._rous than either of the other two, the observations 



themselves are still in progress. Tn the class first referred 
to, viz. surveys in which the observations have been com- 
pieted and the results deduced and published^ may be 



-^ 



-■*. 



r. 




m- 




- * 



^r*:* 



z,_- ^# 

_- ^ 



V-- 



% 



m 



i--^e 



i-ftiKT 



30 



TEKRRSTRIAL MAGNETISM. 



[£. i.II 



named a portion (about the half) of the observations of 
the Antarctic expedition under Sir James Clark Ross: 
those of the expedition under Lieutenant Moore, R.N 
and Lieutenant Clerk, Royal Artillery, also to the Ant- 
arr-^^c Ocean ; of Captain Sulivan, from England to the 
Falkland Islands and back ; of Sir Edward Belcher, (in 
H.M.S. Sulphur,) on the north-west coast of America 
and in the Pacific and Indian Oceans; of LieutenaTit 
Alexander Smith, R.N., and Li- itenaut Dayman, R.N., 
in voyages between England and Van Diemen Island. 
In the second class, viz. surveys completed and in pro- 
gress of reduction but not yet pubhshed, may be enu- 
merated the remaining portions of the observations made 
in Sir James Clark Ross's Antarctic expedition ; a small 
but valuable collection by the Niger expedition ; another 
by Sir Robert Schoinburgk in Guyana; two series on 
the coast of New Holland, one by Captain Wickhani, 



and the other by Lieutenant (since 



.) St 



the observations made in a special expedition to Hudson's 
Bay and back by Lieutenant Moore ; and two extensive 
series, one by Captain Shadwell, in the hydrographical 
expedition of Captain Blackwood to Torres Strait and 



r 



ound New Holland ; and one by Sir Edward Belcher in 



RM 





may 



be 



Amongst the observations now in 
named those of the expeditions to the Arctic Polar Sea 
under Sir John Franklin and Sir James Clark Ross ; of 
the hydrc^raphical surveying expeditions of Cantain Bar- 



^^' 



K 



^.-j 



of Captain Bayfield in the Gulf and River St. Lawrence ;, 



Sect. - 



ofN 



jn 



tl 



Stok< 
valU' 



IS 



Ian 



the - 
Com 

nam( 

in sc 
ports 

d.'iil}' 
netie 

ace a: 

distri 

ever 

curv( 

netie 
finall 

series 
ha 

plishi 

limit 
perfc 
are ; 

of tl 
I'esul 

time 



ve 



th 



e r 



Sect, il.j 



TEHRESTRIAL MAGKETISM. 



^ 



1 



x.^-*. 



u 



i 



V ^ 



,.i 



i^O*-' 



■1 . I 



of Captain Owen Stanley in Torres Btrait and thr- co-ns 



N 



5 



( 




Behring's Strait; 



and of Captain 



To tliese must be added a very 



gst the 



in the Pacific and 

Stokes in New Zeah 

valuable magnetic survey still in progress amonj 

islands of the Indian Archipelago by Captain Elliot of 

the Madras Engineers, at the expense of the East India 

Company. 

When it is borne in mind that several of the above- 
named surveys include periods of three or four years, and 
in some instances not only determ_inations at the several 
ports and harbours which may have been visited, but also 






( 







of the three mas- 




netic elements at sea in passages from port to port, the 
accumulation of materials, and their already extensive 
distribution over the surface of the globe, may in some 
degree be judged of. No part of the globe has yet how- 
ever been considered so far completed, that its magnetic 

F 

curves Lave been finally drawn, or the tables of the ms 
netic elements corresponding to gcograpliical positions 
finally derived from them. The results of eacli individual 
series are computed and published as soon after they 
have been received in a complete state, as can be accom- 
plished by the establishment at Woolwich, which is very 
limited in comparison with the duties it endeavours to 



perform. 



gnet 



are also provisionally drawn ; but the final co-ordination 
of the different series, and their combination with the 
results of the magnetic surveys carrying on at the same 
time by governments and individuals in various parts of 
the remaining fourth of the globe which is occupied by 



r 



r^ 
1 ' 






TERRESTRIAL MAGNETISM. 



[Sect. II. 



laud, is deferred until the accumulation of materials in 
the more frequ^uted portions shall appear sufficient for 
the purpose, and until in the less frequented portions 
there shall be no immediate prospect of any further con- 
siderable accession. The final period at which the work 
may be completed cannot but be accelerated by the step 
which the Lords Com.missioners of the Admiralty have 



taken, in desiring the |)resent notice to be drawn up, and 



in holding out inducement-- to naval officers of professional 



and other advantages, as a recompense for what may in 
some respects be regarded as extra -professional services. 
With due hesitation in expressing an opinion on what is 
future, and contingent on many circumxstances, it may be 
stated that hopes are entertained that the year 1851 may 
see the v/ork completed. 

In prosecuting a work of this general and purely expe-^ 
rimental character, unconnected with hypothesis of any 
sort, the phenomena of all parts of the globe must be 
viev/ed in the abstract as possessing an equal importance ; 
and it does not appear desirable, therefore, to name any 
one of the lines, whether isogonic, isoclinal, or isodynamic, 
as deserving of special attention in preference to others. 
There is one direction, however, which may be safely 
iven, and which it may be well to remember at all times, 
viz.j that " the value of each new station is directly pro- 
portional to its distance from those where observations 
have already been made ;" and in this point of view it 
may be useful to notice, that up to the present time fewer 
observations have been made in the Pacific than either in 
the Atlantic or the Indian Oceans. 




APP 



en* 



E 



U 



c^" 



defle 
two par 
termice 
deflecti< 
magnet, 
from tb 
pendicu 
suspend; 

first par 

T'dio of 
horizoDt 

to the L 
the cube 
of the ne 




Bv'V 



The . 






Eai^ 



Vi 



J 



1. P] 

OMhe 



t( 







^ 



'I, 



Appendix.] 



TERRESTRIAL MAGNETISM 



33 



■ii 



■'''. 



» ^ 



ArPENDIX No. 1. 



Description and Use of the Unifiiar Magnetomkxeh 



h 
il 



Y 

> t 



M 



4 



. 1 



I 



/* <- ' 






F^ 



# . 4 



• f 



it 



The Unifilar Magnetometer consists of two parts—an apparatus for 
deflection, and an apparatus for vibration : these correspond with the 
two parts of the process by which the absolute horizontal force is de- 
termined; the experiments of deflection consist in observing the angular 
deflection of a suspended magnet produced by the iniiuence of a second 
magnet, which is placed on a support at one or more known distances 
from the suspended magnet, and in a line drawn from its centre per- 
pendicular to its direction : the experiments of vibration consist in 



r, 






suspending th^^ magnet which was used -as the deflecting magnet in 
experiments of deflection^ and observing its time ^^f vibration. By the 
first part of the process (or the experiments of deflection) we obtain the 
ratio of the magnetic moment of the deflecting magnet to the Earth's 
horizontal magnetic force at the place of observation ; the latter being 
to the former as 1 to the sine of the angle of deflection multiplied by half 
the cube of the distance employed ; — or if m denote the magnetic moment 
of the needle, X the Earth s horizontal force, r the distance apart of the 
centres of the magnets, and u the angle of deflection, the expression 



m 
X 



J r^ sin u. 



By the second part of the process (or the experiments of vibration) the 
product of the same two qualities is obtained : being the quotient of a 
constant, which we may call t^ K (see p. 3S), divided by the square of 
the time of vibration: or if T be the time of vibration. 



m X 



■cr 



«K 



T* 



m 



The values of m X and ~ being known^ those of m and X may be 



X 



obtained separately: for if we call m X :^ a and 



m 
X 



jS, m (the 



magnetic moment) = V ^ /^' ^"*^ ^ (the horizontal component of the 



Earth's magnetic force) 




DefuJcion Ea-perments, 



1. Place the tripod base and copper box upon the stand, and screw 
on the torsion tube; form a thread capable of carrying the smaller 

C i 









fr1 






TERRESTRIAL MAGNETISM. 



[Sect. IL 



ApP* 



niagnet, ?'. e,, the magnet of 3-00 inches In lengtli (a single fibre of silk 
is generally strong enongh to support it); affix the deflecting rod, and 
the telescope and scale ; level the base circle very correctly, suspend the 
3-inch magnet, and raise it until it is in the same horizontal plane -with 
the deflecting nijgnet when resting on the supports. 

2. Place the 3-67-inch (or deflecting) magnet on the graduated support 
to the ^est of the suspended magnet, with its centre at the distance de- 
termined upon, and "with the north end towards the East. Turn the 
telescope in azimuth until the central division of the scale attached to 
the telescope is on the vertical wire ; write down the readings of the 
%^erniers, and the height of the thermometer placed near the deflocting 
m agnet. 

3. Reverse the deflecting magnet, placing the south end where the 
tiorth was, and bringing its centre precisely to the same distance from 
the suspended magnet as before. Turn the telescope until the central 
division of the scale is again on the vertical wire, and write down the 
readings^ together with the height of the thermometer. 

4. Eepoat these observations by reversing the deflecting magnet again 
and again^ until, judging by the agreement of the several results, suffi- 
cient accuracy appears to be obtained. Two or three repetitions will 
generally be found to suffice. 

5. Place the deflecting magnet at the same distance on the opposite 
support, and repeat the > 



series of observations, commencing as before 
with the north end of the magnet towards the East. Take a mean of 
the readin|i,o of the circle in the 1st and Srd positions of the deflecting 



magnet, and another mean of the readings in the 2nd and 4th positions ; 
half the difR^^rence of these means will be the angle u corresponding to 
the distance r. The distance r should be such as to produce a sufuciently 
large deflection iu the suspended magnet. At Woolwich, where the 
value of the horizontal component of the terrestrial force is 3' 7? the de- 
flecting magnets of 3*67 inches m length, when recently magnetized, will 
usually produce a deflection of about 10", when the distance from centre 
to centre of the magnets is 1-3 foot But with a constant distance the 
deflection would inert: je in localities where the horizontal component is 
less, and diminish where it is greater: the deflection would also be 
diminished if the deflecting magnet lost any portion of its original charge. 
It is not desirable that the deflection should be less than 6^. 



When the diitanee required to produce a sufficient deflection is less 
than ii\v times Vi^^ length of the deflecting magnet, the amount of the 
deflection is liable to be influenced by the distribution of the magnetism 
in the m_agncts employed, which does not follow the same law in all 
magnets. In such cases it is necessary to employ two or more distances 



they 

lessei 
sponc 

Wl 

perifi 

veuie 

1. 

magn 

of re] 



1 



1 



r^ 



ciis 



f 



2. 



arnij 

3« 

4. 
1 and 

tlian 1 

obtaii 

distan 

ofafc 
rily e 

sindt 



whea 



1. : 

furnih 

A teh 
tiou i 
glaz.,. . 

(or u, 

stirru 

centre 
fnrin 

the 111 
*>f the 



_-^**^x^; 



m 



4 



i. 



Appendix.] 



TERRE8TEIAL MAGNETISM. 







hA 



i1 



1 



, ^ 



V 



\ #■- 



h^ 



for the purpose of elimiaatiBg thib eifect. If two distances are employed, 
they should be to each other in the proportion of 1 to 1*3 nearly ; or for 
magnets of the specified lexigth and Btrength, 1 foot r,ad 1*3 foot mixy 
;enera]ly be found conveuient and suitable distances, in which case the 
lesser distance should be denoted by r, ai^d the greater by r,, the corre- 
sponding deflections being ii and u.. 

Where two distances are employed, no alteration is required m the ex=- 

periments of vibration ; but in those of deflection it wili be found con- 
venient to adopt the following routine : 

i. Observe the angle of deflection -with the Borth end of the deflecting 
magnet altei'nately to the east and to the west (with the proper number 



arm 



least of the two distances. 



2. Go through the same process with the magnet still on the eastern 



arm 



3. Repeat No. 2 oa the western arm, and 

4. Eepeat No. 1 on the western arm, the order of the distances in Nos. 
1 and 2 being Inverted in Nos. 3 and 4. 

If the distance required to produce a suflicient deflection should be less 
than four tinies the length of the deflecting magnet, it may be dt/rable to 
obtain three or more values of w (u, u,^ u,,^ &c,) at three or more distar/.s 
(r, fj, ryy, &c.) ; in such case it is convenient for the calculation that the 
distances should have a common difference ; as, for example, (in dedaials 
of a foot) '9, 1 • 1, and 1*3: 1*1 being supposed to be the distance ordina- 
rily employed when time and circumstances will not pei-mit more than a 
single distance ; and the other two distances to be employed iu addition 
when there may be full leisure for the purpose- 

Vibration Experiments, 

1. For these experiments che tripod stand carries a table top, Tvhich is 
furnished with an azimuthal motion, and can be clamped to the tripod, 
A telescope with a scale attached to it for measuring the arc of vibra- 
tion is fixed to the table, as is also a rectangular box of wood, with a 
glazed side, furnished with a tube for the suspension of the 3' 67 inch 
(or deflecting) magnet. The talde must be levelled by means of the 
foot-screws, and turned in azimuth until the mirror attached to the 
stirrup in which the magnet is supported refleels in the telescope the 
centre division of the scale attached to the telescope. The magnet rests 
during the experiments of vibration in a stiri'up carrying a mirror, and 
is suspended by a silk thread of which the ratio of the torsion force to 
the magnetic directive force must be ascertained, by turning the index 
of the torsion circle 90°, first in one direction and then in the other, and 
taking the mean of the correspondiug angles through which the magnet 






MH*t 



\^ 






TERRESTRIAL MAGNETISM, 



[Sect. ir. 



APP^ 



is deflected. Then if H dein 
P the Earth's directTTe force. 



co-effi 






the m ean angle (in minutes of are) 
90" — the mean angle (in minutes of arc)' 



2, The mr.:;- ■ ■, being at rest, must be made to vibrate in small arcs 
by V ms of another magnet, and the time of 300 vibrations observed ia 
the following manner ; — The arc of vibration being about 60 divisions 
(or minutes) on either side of the central division, note the time when 
the central division crosses the vertical wire of the tekscopoj passing 
from left to right ; do the same when the central division passes from 
left to right for the third, fifth, seventh, ninth, and eleventh times 
corresponding to the completion of vibrations 4, 8, 12, 16, 20, aud 24. 
This will gi%^e the approximate interval of time in which 20 vibrations 
are performed ; and will indicate to the observer, without requiring him 
to count tlie intermediate vibrations, when he should be prepared to ob- 
serve the completion of the 60thj I20th, 180th, 240th, and 300th vibra- 
tions. At the 300th vibration he should recommence taking- the time of 
the 300th, 304th, 308th, 3I2th, 3ieth, 320th, and 324th vibrations. He 
will then have seven partial results for the time in which 300 vibrations 
are performed, viz. 



to 300 
4 to 304 
8 to 308 



12 te 312 

16 to 316 

20 to 320 

24 to 324 



of wlucli seven partial results he should take the mean. 

The temperature of the magnet should be observed by a thermometer 
placed in the box with the magnet, before and after the experiments by 
which its time of vibration is determined. 

The data required from the observer on each occasion are the follow- 
ing:— The mean time of 300 vibrations, and the particulars from which 
it is derived (or the partial results) ; the commencing and concluding 
arcs of vibration : the temperature of the magnet ; the rate of the chro- 

by which the times are observed ; and the ratio of the torsion 



nomeier 



force to the Earth's directive force, or — • 

F 

If, then, T' is the observed time of a single vibration, and T the 
corrected time, the corrections may be computed by the following 
formula : 



T 



T 
X 




I + 



TT 



2F 



a a 

Te 



8 



— ) 



in v^hich a and a^ are th- commencing and concluding arcs in parts of 
radius, and x the rate of the chronometer. When the commencing arc 



^ 







friW 

It is 
the ab: 

make 1 
rinient 
descrit 

such c 

gtation 

happen 
The 

the cir 

of the 

magne 

momei 

withtl 

diamet 

denote 
weight 



and if ' 
of vibrj 
the ma) 
the fon 



e< 



Asth 

before t 
^^alue n 

stirrup , 

observe: 

If the 
ofdefi 

the exf 

at the 1 

temper^ 

*^«^ req 
<?ustonia: 

tempe, ^ 



. » 



wi-^ ^ 



Appendix.] 



TERRESTRIAL MAGNETISM 






•'■i 



rU 



r 



Vjjl 



4« 



j! 






He 



i 



by 



0'- 



r f , 



of vibration is as small as above directed, the correction for it may be 
disregarded, except wlien great accuracy is sought 

It is desirable to commence the observations for the determination of 
the absolute horizontal force with the experimenis of vibration ; then to 
Hiake the series of deftection experiments ; and then to repeat the expe- 
riments of -vibration. The experiments of deflection and vibration thus 



described will cr-- plcte a single determination. There should be three 
such determinations with each of the 3* 67-inch magnets at a base 
station; and all should not be made on the same day, lest it should 
happen to be a uay on which the magnetism of the Earth is disturbed. 

The constant tt'-* K (page 34) is obtained from tt, denoting the ratio of 
the circumference of a circle to its diameter, and K the moment of inertia 
of the magnet, including the stirrup (and its appendages) in which the 
magnet rests during the experiment of vibration- To determine the 
moment of inertia, the magnet, stirrup. &c. is vibrated a second time 
with the addition of a metal ring, of which the exterior and interior 
diameters, as well as the weight, are accurately known. If r and r' 
denote the exterior and interior radii, (in decimals of a foot,) and w the 
weight, (in grains,) the moment of the inertia of th<: ring Is 



K' 



^(r2 + /2) W; 



and if T denote the time of vibration without the ring, and T^ the time 

of vibration with the addition of the ring, the moment of the inertia of 

the magnet and stirrup in the vibrations without the ring is given by 
the formula, 



K 



^'{t^^ 



T^ 



T 



a 



As this determination requires several repetitions, it is usually made 
before the instrument is put into the hands of the observer ; but as its 
value must be found afresh if any alteration be made at any time in the 
stirrup or its appendages, a ring is always supplied for the use of the 

observer. 

If the temperature of the magnet be not the same in the experiments 
of deflection and vibration, the value of »i X as obseiyed at the time of 
the experiments of vibration, must be reduced to that which it had 
at the time of the experiments of deflection. For this purpose it is 
necessary to know the amount of change in the magnetic moment of the 
magnet occasioned by one degree of temperature. This is called the 
temperature coefBcient, and is usually denoted by q. As its determina- 
tion requires apparatus with which ships are not supplied, it has been 
customary to furnish it with the instrument. Then if t and to be the 
temperature of the magnet at the times of deflection and vibration 



'j^ 




o 



58 



TERRESTRIAL MAGNETISM. 



[Sect. U 



ApP^ 



• -H 



* 



respectiveivj m X derived from the experiments of vibration, becomes 
when corrected to the tenipei-ature of the experiments of vibration ; 



m 



X[l+q (t-ty\ 



The absolute horizoutai force determined by the foregoing process will 
fin-ally require a very small correction, on account of the circumstance, 
that the magnetic moment of the deflecting magnet is not strictlv idcu- 
lical in the different positions in -v^hich it is placed in the experiments of 
deflection and vibration, as it is perpendicular or nearly so to the magnetic 
meridian in the first case, and coincides with it in the other. In the 
first ca^e, the magnetic moment is tha.t proper to the bar itself; in the 
second case it is augmented by the inducing action of the earth. The 
coeificient for this correction requires a separate apparatus for its deter- 
mination, and the correction m.ay be applied to the results when finally 
re-computed at Woolwich, as it requires no special data to be furnished 
by thf^ observer. 



APPENDIX No. 2. 



DiBKC 



FOR USING Mr. Fox's Apparatus tor observing the 
Magnetic Inclination ani> Force. 



T, — Gensral Eemaeks^ 

In fixing the gimball table, it is convenient that it should be so arranged 
that when the apparatus is placed on it, the zero divisions of the horizon- 
tal circle should coincide with the fore and aft midship-line of the ship. 
la preparing for an observation at sea, the circle should be turned in 
azimuth until the vernier of the horizontal circle shows an angle with its 
;^ero, corresponding with the difference between the magnetic meridian 
and the coarse which the ship is steering. The plane of the circle will 
then coincide with the magnetic meridian, when the ship is steadily 
steered. When from circumstances of weather, &c., the steerage is diffi- 
cult, an assistant is required to indicate to tlie observer the times when 

the ship is steady on her course. 

The apparatus is usually furnished with three or four needles, one of 
which is intended to be used on shore for the determination of the true 
inclination (when no special instrument is provided for the purpose), by 
the process subsequently described, Appendix 3, in which the poles are 
reversed. The other needles, which are intended for the intensity, are 
never to have their poles reversed, and care is to be taken not to place 
them inadvertently near other magnets or iron. Besides Oxe needles. 



i 



[ 



- 
^ 

^ 



tne 0^ 

he ^^^ 
the bo: 

It is 

case of 
one of 

injure ' 



ne^ 



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• 1 



the py 

pivot s 

bi-ackei 

angle c 
be less 
is u5na 
tween e 

&c.), 
nom': .. 
preserv 
of the s 



gimba:: 
the ma 

release ■ 
tioa of 

ivory di 
h the ■ 

positive 
^heu ti 



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f\ppeiidix,] 



TERKESTUIAL MAGNETISM 







^Sv 



•o 



'Ji 





- we 
^^ The 



r 







.-^ rnt 



* 



tvro other magnets are supplied to be used as deflectors. In replacing 
the needles and deflectors in tlie travelling box, cnre should always 
bo taken that the poles of each occupy the places marked for them in 
the box. 

It is desirable to use always the same needle at sea, and to keep it 
always mountedj clamping it before it is put away for the day 5 but in 
case of its undergoing any considerable deteriorntion from use or accident, 
one of the other intensity needles may be substituted for it. 

When changing the needles at a land station, be very careful not to 
injure the jewels, or the terminations of the axles of the needles ; when a 
needie is changed it is desirable to hold it chiefly by the grooved wheel ; 
the piTOt should iirst be put into the outer jewelled hole, and the opposite 
pivot should be carefully guided into the hole at the back whilst the 
bi*acket is screwed up. 

With respect to the constant weights, it is dc^'rable that the smallest 
angle of defitction produced hy any of the weights employed should not 
be less than 30°. On account of possible instrumental irregularities 
is usual to employ more constant weights than one, with difiierences be- 
tween each of half a grain, (as for exaniplp 2 grains, 2^ grains, 3 grains, 

Great care is taken that all the weights which have the same 
nominal value sh -"rid be equiponderant, but it is desirable if p.\ : Ible to 
preserve the same identical weights throughout the whole observations 
of the same relative series. 



it 



&e.). 



tr*-:^ 



-P- 






1* 

4 



;ir 



p -- 



-* AiK 



k' 



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* ( 



II, — Observations at Sea. 

A. — IncV ation, 

1. Direct Observation, — The instrun: ^t having been placed on the 
gimball stand and levelled, and the plane of the circle made parallel to 
the magnetic meridian, with the face of the circle towards the East, 
release the needle, which will immediately take approximately die direc- 
tion of the inclination ; rub gently the centre pin at the back wdth th 



ivory disk, and read otf successively the divisions of the limb indicated 
by the two ends of the needle t note the readings, which will be +, or 
positive, when the North pole of the needle dips, and — , or negative, 
when the South pole of the needle dips : repeat the observation three 
times, turning the bracket which supports the needle a small quantity be- 
tween each observation, and being careful to rub the centre pin at the 
back with the ivory disk whilst reading off. The bracket is turned by 
means of the screw heads at the back of the circle, and the object of turn- 
ing it is to cause the ends of the axle of the needle to hare different points 
of bearing on the jewels in each obsen/: 

In reading the divisions on the limb, be careful always to bring the 



^on. 



> 



40 



TERRESTRIAL MAGNETISM 



[Sect. II, 



division nearest to the needle to coincide with the corresponding division 
of the second graduated circle iminediately behind it, by which means 

parallax is avoided. 

The mean of the three observations or six readings above described is 
the apparent inclination by direct observation with the facf East. 

2. Observation -with Deflectors, — Having made the preceding observa- 
tion, screw in the deflector N (or the north pole of a second needle 
used as a deflector), and adjust the circle at the back by means of its 
verniers, so that the deflector may be 40^ on one side of the division which 
in the preceding procesb (§ 1.) was read off as the direct observation 
with the face East. The needle will then be repelled, and will settle on 
the opposite side of the dip ; read off (always whilst rubbing with tlic 
ivory disk) the divisions indicated by the two ends of the needle. Re- 
peat tho observation three times, altering the beariiigs of the ends of the 
axle between each observation as before directed. Turn the back circle 
through SO^^, so that the deflector may Be 40° on the other side of the 
apparent dip. Move the needle ])y the bi'acket, so that it may be de* 
fleeted on the opposite bide of the apparent dip to what it was before, 
and make three observations. The mean of the six observations or 
twelve readings is the apparent inclination with a deflector, face East, 

Instead of placing the deflector -m 40^, another angle, as 45° or 50°, 
may be taken ; or a second angle may be used for the purpose of varying 
the observations when it may be desired to repeat them ; the only essential 
point being, that the angle at which the deflector is placed should be the 
same on each side the apparent dip. 

' Instead of deflector N (or the North pole of a second needle used as 
a deflector), deflector S (or the South pole of the second needle) may be 
screwed into the opposite point of the back circle, and six observations 
taken with it will give as before the apparent inclination with a deflector, 
face East. 

In writing down the obsei'vations the following directions must be 
attended to; if the needle be deflected past the vertical the division cf 
the limb should be read off according to the graduation and noted 
accordingly, but the mean of the readings must be taken from 180% in 
order to give the true arc corresponding to the position of the needle: if 
it be deflected past the horizontal, the readings must be entered as 
marked on the limb, but with the negative sign preflxed, in which case 
the mean result will be half the difference of the means of the negative 

and positive readings. 

The apparent inclination obtained as above directed, whet'^ r by the 
direct method or with deflectors, requires two corrections to give the 
true inclination, viz.— 1'^ the index-correction of the particular needle 
employed, and 2° a correction for the influence of the ship's iron de- 



4 



1 

] 



I 



i 



J 

I 



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ii 



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tiree r^ 


--* 


-.1 


vr" 


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Appendix.] 



TERRESTRIAL MAGKETISM. 



41 



pendent on the direction of her head at the time of observation. The 
mode of obtaining these corrections will be subsequently explained. 



J . 



1.1^ 



Pf^K 



^ils 



I 



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"'■•'uAj 



ft ,^ 



n 



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B. — Intensity. 

3. W//^ Weights,— The 5n=?trunieTit being on the gimball tabic and 
levelled, the plane of the circle parallel to the magnetic ir.eridian, with 
its face to the East, and the needle shewing the magnetic dip, place the 
silk carrying the hooks on the grooved wheel; attach one of the constant 
weights to one of the hooks, and take three readings of the division of 
the limb at which the needle is in equilibrium, using the precautions 
already directed of altering the points of support of the axle between 
each observation, and rubbing with the ivory disk whilst reading off. 

If the needle is deflected past the vertical or horizontal, read and enter 
the angles as already directed under the head of Inclination. 

Change the weight to the other hook, when the needle will be deflected 
to the opposite side of the apparent dip tr> what it was before, and take 
three more observations. Half the difference of the mean ;f the arcs 
with the weight on either hook is the angle of deflection due to the con« 
stant weight employed; or half their sum, if one of +he arcs was past the 
horizontal and lias therefore the negative sign prefixed, 

4. With Deflectors, — The instrument being adjusted as already de- 
scribed (and without using the hooks, which are only designed for tlie 
observations in which the weights are used), adjust the circle at the back 
by means of its verniers to the apparent dip, so that the deflectors, when 
screwed in, may coincide with the line of the dip; the needle will then 
be repelled to one side; make three observations of the division to which 
the needle is thus deflected, observing the usual precautions of moving 

the bracket at the back, reading both ends of the needle, and rubbing 
with the ivory disk. 

Move the needle past the deflector to the other side of the dip by means 
of the bracket, and take three more observations: if the needle is de- 
fleeted past the vertical or horizontal, read and enter the angles in the 
manner already described ; half the difference of the arcs on either side 
of the apparent dip, or half their sum if one be past the horizontal and 
have the negative sign, will be the angle of deflection produced by the 
deflector. Instead of the deflectors a second needle may be used as a 
deflector, either with the end of the needle-case marked N (containing 
the north pole of the needle) screwed into the arm marked N, or the end 
marked S screwed into the arm marked S. 

The thermometer attached to the circle m.ust be observed at the com- 
mencement and close of the observations of intensity, whether with 
deflectors or weights. 



^^ 



.] 



t-:* 



42 



TERRESTiUAL MAG^^ETISM, 



[Sect II. 



A convenient routine of the observations at sea may be stated as 



er- 



follo^vs : 

1. Take three observations of the apparent dip by the direct ob^ 
vatlon, 

2. Screw in the deflectors N and S, and adjust the back circle to the 
dip. Make three observations of the angle of deflection produced on either 
side of the apparent dip ; this furnisher one result for the intensity of 
the magnetic force. 

3. Repeat No. 2 -^ith a second needle used as deflector N, ^vhich will 
;ive a second result for the intensity of the force. 

4. Repeat No. 2 with the second needle used as deflector S, which will 
give a third result for the intensity of the force. 

5. Renjove the deflector and repeat No. Ij which will give a second 
result for the apparent inclination. 

On days when the weather permits, observe the intensity also by the 
constant v^eights. 



111.— Observations on Shore. 

1. The instrument being adjusted with the plane of the circle coinciding 
with the n-agnetic meridian^ and the face East, make a complete series 
of observations of the Inclination with and without deflectors, and of 
the Intensity with the deflectors and weights, similar in all respects to 
the observations which have been or which are intended to be made at 
sea ; the needle, deflectors, and weights to be those employed, or to be 
cirnployed, in the sea-observations. 

unfurnished with a separate apparatus for determining the true 
inclination, substitute in Mr, Fox's apparatus the needle which admits of 



2. 






its poles being reversed (viz. that needle which is not intended to be used 
in observations of intensity), and obtain the true inclination from the 
mean of the angles read in four different positions of the instrument, viz. 
with the face of the circle East and West, and repeating the process with 
the poles reversed, following the directions for reversing the poles given 
in Appendix 3. The difference between the true inclination thus 
obtained, and the apparent inclination with the face East observed with 
the needle used at sea, ascertained at the several shore stations, furnish 
one of the data from which the index correction to be applied to 
the observations made at sea ia to be computed. 

3. When Mr. Fox's appar-atus is furnished with more than one needle 
for the observations of intensity, -ach needle must be successively sub- 
stituted in the shore observations for the needle used at sea, and ihe 
inclination as well as the ang-les of deflection with constant weight? 
observed with at. 



f 



r 



I 



[ 



i 



i; 



A?P 



)em^^ 



Ob- 



1^ 



1. pi^^ 

the foiloif 
of thu dip 



tlie 



. .^,j^g 



so VM t- 



1. 






piate, ,. 
vertical t.- 

raise i-u; \ 
alter ' \ . 



f ■* 






t^ *^ ^^ 



% ^^ ^X 



liAUt^JLt \ x^ A-C 

of *'' 



Jb & 



horizontal 
aziraath, sc 



cro.M 



^■^ ^. T ^ 



Kepea^ the 
of the ve 



^■ 



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-<-" 



^'' the ^^ 
*« Piaae o 



plate brt 



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as 



Appendix.] 



TERRESTRIAL MAG XETIS3I. 



AP, 



*■ 1 



«.'*!-* 



i:r. 



* t 



APPENDIX No. 3 



'^1 



-* 






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eiHJ 



OBSrBTATIONS OF THE InCT.IM^TION, ^^VITH BaIIKO%V^S CiECLE FURNISHEB 

WITH Mtchoscopks ANB VEaNISIlS. 

1. Place the instrument on a tripod stand, and level it by mcun^ of the 

.ridian bv 



f jot-screws : then bring the ycrtical circle into the masrnetic n 



the following process :~PIace the needle designed for the observation 
of the dip on the agate supports, -with the side of the needle on which 
the letters are inscribed facing the microscopes. Turn the vernier plate 
so that the microscopes mdj be nearly in a yertical line; clamp the 
plate, and set the lower vernier to 90'^ by the tangent screw. Turn the 



d 



3 



vertical circle in aximuth^ so that its face may be to^rards the Souths an 
until the North pole of the needle is bisected by the wire of the microsc . .e 
raise the Ys and lower gently ; if the bisection of the needle has been 
altered, correct by turning the circle in azimuth. Clamp the horizontal 
circle, and read off its yr-rnier, calling the reading A. Now set the 
upper vernier to 90^, imclamp the horizontal circle, and roovc in azi- 
muth (if required) until the South pole of the needle is bisected bj C.^ 



i. Lve 



of the upper microscope. Raise the Ys and lower gently; correct the 
bisection (if necessary) by moving the circle in azimuth : clamp the 
liorizontal circle and read its veraierj calling? the reading B. Now 



0^^ 



unclanip the horizontal circle, and turn the vertical circle IS 
azimuth, so that its face (by which is meant the side on which the mi- 
croscopes are) which was before to the South may now be to the North. 
Repeat the process described above, which will give two other readings 
of the vernier of the horizontal circle, which call C and D. Then 



A + B + C -i- D 



4 



E. 



will coincide with the magnetic me 



the division of the hor' -nital circle to which the vernier should be 
set, in order that the plane of the vertical circle may be at 7-ii/ht angles 
to the magnetic m— idian ; theretore, when the vernier is set to 90 ±E. 
the plane of the vertical circle 
ridian. 

The vertical circle being now placed in the magnetic meridian, 
with its face to the East, the needle will direct itself approximately to 
the inclinati<m ; raise it bj the Ys and lower it gently on itb supports - 
bring the lower microscope to bisect the North end of the nei-dle, clamp 
and adjust exactly by the tangent screw, read off the vernier, which will 
be Face East^ North EncL By means of the tangent screw of the vernier- 
plate bring the upper microscope to bisect the South end of the needle, 



rirl 



44 



TERREcjTRIAL MAGNETISM. 



i^Sect IL 



enu. 



and read its vernier, which will be face East, SotUh end; raise the Ys 
^ud lower gently ; repeat the reading?;, comixiencing now with the South 

The mean of the four readings iis the incliuation with the face 
±.ast^ poles direct, or B,. 

3- Turn the vertical circle 180^ in azimuth, and repeat the process 
in No. 2, taking again the mean of the four readings./^rhich will be 
180' — ^^; 0.^ being the inclination -with the fece West, poles direct, 

4. The poles of the needle must now be reversed by means of the bar 



rnagnetb. 



by the following process : — Take the needle off the agates, 
Luiding it by the end which in the preceding observations was a South 
pole, arid which is now- to be converted into a North pole; place it with 
the flat Side (which is lettered) uppermost in the wooden frame dcsi--^ned 
to prevent any injury occurring to the axle, being careful that the end to 
be made a North pole is placed towards that part of the v. uoden frame which 
is marked accordingly ; secure the needle by the brass centre-piece, and 
place the frame \vith one end towards the I'ight hand and the other 
towards tb( left, and let a;; assistant keep it in that position. Now take 
tbn bar-magnets, one in each hand, and let the North pole of the bar- 
magnet be lowermost in the hand which is towards the end of ^i\< ^'^ame 
in wliich that end of the needle is placed which is to be made a Soutk 
pole; and let th^ South pole of the bar-magnet in the other hnnd be 
lowermost. Draw^ the magnet about ten limes along the flat side of the 
needle : the North pole of one bar-magnet being drawn along the end of 
the npedlt; which is to be made a South pole ; and the South pole of the 
Other bar-magnet being drawn along the end of the needle which is to be 
made a North pole. The needle must then be turned over in the wooden 
frame, so that its other flat side may become uppermost, which must also 
be rubbed by the m .^nets ten times in the manner already described. 

The bar-magnets should be held one in eacls hand, nearly in a vertical 
position, the lower ends resting on the needle ; and must be drawn al 



o 



the grooves in the wooden frame from near the centre to beyond the 



ends of the needle. When the process thus described has been guue 
through, it w^ill be found, on replacing the needle on the agates, that the 
end which previously dipped below^ the horizontal line is now inclined 
hove it. 



a 



5. The observations in Nos= 2 and 3 must now be repeated, which will 
S^ive two other mean readings with the face of the circle first East and 



thei 



W'--- These readings will be B^ (the inclination with the face 
East^ poles reversed) ; and 180^-04; B^ being the inclination with the 
face Wcsty poles rever^^ed^ Then 



6y f ^2 + ^S + ^4 ^.^ 



4 



^, 



ihQ- true magnetic inclination at the place of observation. 



r 



f 



f 

i 



f 



^ 



^npeii 



dixJ 



6. '^^' ' 

' - results ' 

repeat the o 

7. On 
die a 



>: *T 



**v 



ifht: 



,-> .-- ^r 



■>9 . 



Q 



' fV^ ^' 



.. j1 






e 



direct: ai3^ 

Dr. Lloyd 

for irteasiu"- 



approac' 



c 



iiid.l^~lng 
|i,e dip l^v a 

nee" ■ n':d i 

^ ^d. F 



i 



I. '; d with 
in winch thp 



su 



V i1!0. 



i - 






"^^ "ping, 
of tbfi pi 



tr 



'**> 



^eflu 



'^ircle t 



in 






-'"-^ to the i 



^ i. r 



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A 



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s 



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n 



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r 



Appendix.] 



TERRESTRIAL MAONETIS3r. 



45 



6, Two such detenniaatioDS will generally be found sufficient, bat it 
the results differ from each other more than 3- or 4' it is desirable to 
repeat the observations, 

7. On arriving at a new station it is alwavs desirable to 



- .'^ <> r^' 



e the 



needk^ afresh before the observations are comi-enc.-:!.- It is iuaitferent 
whetla. . an observation is commenced with the end marked A as a North 
or as a South pole ; bat it is convenient to call that state of the needle in 
which ^^e end A is a South pole, and the end B a North pole, "poles 
direct/' and vice versa. 



4- 




Dr. Lloyd has recently suggested a niode of employing this iustrumen 
for measuring the absolute total force in localities where the inclination 
approach* ? 90"^, and where the usual method of ascertaining the total 
force from its horizontal component ceases to be satisfactory. It consists 
in deflecting the dipping-needle from its natural direction in the line of 
the dip by a second magnet whose magnetic moment is correctly known, 
placed at one or more accuratcdy measured distances from ihe centre of 
the dipping-needle, in a line at right angles to tlie magnetic axis of the 
needle, and in observing ^.^refully the amount of the deflections thus 
produced. For this purpose the vernier-plate of the inclinometer is fur- 
nished with two additional arms perpendicular to those which carry 
the microscopes and verniers ; one of these arms is prolonged by an 
additional piece (removable when not in use) carrying a gn -::iac-.d tube 
in which the magnet is placed, and in which it can be fixed by binding 
screws, with its centre at different distances from the centre of the 
dipping-needle and in the same vertical plane with it. The deflectin 
magnet being placed in the tube, and fixed at a suitable distance from 
the dipping-needle, with its North pole towards the needle, and the face 
of the circle towards the East, the microscopes are brought to coincide 
^ith the ends of the needle in the new or deflected direction. The 
deflecting magnet is then also in its required position, namely, at right 
angles to the line joining the two extremities of the needle. The arcs 
tre read with the precautions already described in the directions for 
observing the inclination. The deflecting magnet is then taken out of 
the tube and replaced at the same distance as before^ but with its South 
pole towards the dipping-needle, and the arcs are again read. This 
double process is repeated with the vernier-p- :te turned nearly through 
a seuiicircle, so that the deflecting magnet is brought on the other side 
of the dipping-needle to that which it occupied before: the face of the 
circle is now turned towards the West, and the observations already 
described are repeated. The arcs thus obtained i^ive four values for the 
angle of deflection, the arithm.^'tie:^' mean of which is taken as the 
deflection («), corresponding to the distance (r) in decimals of a foot. 



'f 



' 



46 



TERRESTRIAL MAGNETISM. 



[Beet. II. 



If then m he the magnetic moment of the deflecting maguet, and * the 



total lorce m absolute measure : 



m 



<P 



J r^ X sin u. 



The Inclir ueters s^^-i :''ed to the expeditions under Sir Jaaies Ross 
and Sir John Richardson are furnished with the additional apparatus 
for this purpose. The dipping-needles are 3-5 inches in length, and the 
deflecti:ig magnets are those of 3*67 inches, belonging to the iinifilar 
magnetometers, which also make a part of the equipment of these 
expeditions. 

The chief practical difficalty which appears to present itself hi the 
^niployineut of this nietliod consists in the small distance apart at which 
it is necessarj' tc place the two magnets^ viz,, the deflecting magnel and the 
dipping-needle, in order that the angle of deflection may be of a suffi- 
ciently large amount. The angle consequently is very considerably 
influenced by the law according to which the free magnetism is distributed 
in the particular magnets, and a long process of observation and of cul- 

niiired to eliminate this effect. The formula by which 



dilation is re 

the total force is deduced becomes in effect 



m 



<t> 



-. \ . 



>*4 



f v sm u 




1 



i + 



P 



Q ^ Iv 



-, &c.^ . 



>fi 




whe 



P, Q, R, &c., being coefficients depending upon the distribution of the 
free magnetism in the deflecting magnet and dipping-needle, and of which 
the values must be determinea by experiments at different distances. 
This process may, however, bf^ gone through in England before the in- 
struments -ire supplied to the officers, or after they are returned ; it has 
been partially accomplished at Woolwich for the magnets supplied to 
the Arctic expeditions aboTcnamed. Tl -^ rernaining observations re- 
quired for a determination by this method of the total force in localities 
re the dip approaches 90^ present no particular difficulties, and may 
be made on shore or on the ice whenever the er^pedition is stationary tor 
a few hours. It is necessary, however, to be very particular in observing 
the temperature of the deflecting magnet whenever it is employed in 
producing deflections, and to know very accurately its temperaturt: co- 
efficient at dillerent parts of the thermometric scale; and it is also 
necessary to combine in some satisfactory manner the observations 
(described in App. 1) by which the magnetic moment of the deflecting 
magnet is examined, with the observations in which it is made to deflect 
the dipping-needle. 









App 



en^i^'^ 






C 



y^ S' 



.vV 



th< 



111 thei" V-; - 
.-.. as in>^i2a' 



"-- ^hip. 



11 ^n^ 



f the omect b 






nu. 



ae ^nm 



r*^'' u 



1 ^ 



■^ \A^* 



\ 






UV V 



/u,.,rvatiOD 



2. Repeat f^' 

onr^^^ofthe 
or the ratio of 

^rom the ship, 
"J iron 1 






'ifipass oa V- 



^1 



. * 




■ -ms e 

' ■o'oservt: 
'^A tne com 



■V 



- 3 r h 



it 



^^^^on th. . 



% 



'ill sb 



m 



^^'^^ the 



^^'-.. , 

^ ' -^d 

'^'^^F-.- 



; to the e 

' '"'^^ -^f t] 



J^ 



01 



4 



^ 



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II, 



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f » 



**e 



Appendix.] 



TERRESTRIAL MAGNETISM. 



47 



ifPPENDIX No. 4. 



^^^V<J 



U: 



ijt iV- 



■^-^ -t 



■ ^ *-44 



Y- 



' . 1 



1 






iflT 



* V 



Observations kkquired to determine the Effect of the Shix-'s 

Iron on the Magnetic Instruments ttseb on boarb. 

1. When the ship has got her guns, shot, and iron stores on board, and 

in their places, and has her boats, stanchions, and all other iron-work 

in the positions in which they are to remain at sea, her head must be 

^nccessiTely placed upon each of the sixteen principal points of the coni- 

)as=:, as indicated by the standard compass used in its proper position in 



'^^ ship. When the ship is quite steadyj and her head is exactly on the 
oint on -which it is first to be placed, the bearing of some distant and 
'ell-deliised object must be noted by the standard compass, the distance 
f the object being such that the space through which the ship revolYes 
n being swung round shall make no sensible difference in its bearing : 
he magnetic inclination by the direct observation with Fox's apparatus 
aust also be noted, and the angle of deflection produced by a second 
leedle used as deflector N, in the manner described in the directions for 
he obser%'ations of the magnetic force with that apparatus (§ 4, page 42)- 
2. Repeat these three observations (viz., the bearing by the standard 

L * 

ompass of the distant object, the inclination, and the angle of deflection 
or the ratio of the force), when the ship is steady v, ith her head placed 
^ -, jsively upon each of the sixteen principal points. 

L Determine the real or true magnetic bearing of the distant object 

from the ship, by taking the standard compass to some place on shore 

ffhere no iron may be near, and fruiii whence the position of the standard 

;ompass on boai'd and the distant object shall either be in oue, or in 

irections exactly opposite to each other. The bearing of the distant 

bject observed from this spot will be the ti'ue magnetic bearing, or that 

hich the compass should have shown in eaoh of the sixteen observa- 

ons on board, had it not been for the iron in tlie ship. The differences 

etween the true magnetic bearing and the successive bearings on board 

.^iil show the amount of the error occasioned by the ship's Iron, when 

16 ship's head was placed on each of the slxtec^'^ points. Call the 



4^ 



r- 



rror East, or 



3 



in the cases in which the North end of the ueedle is 



rawn to the eastward by the ship's attraction, and West, or +, when 
-v/n to the westward. Observe also and record the magnetic inclina- 
*n on shore with Fox's apparatus by the direct observation and with 

.e face of the circle to the East, precisely as when on board, as well 

3 the angle of deflection produced by the second needle used as de- 
lector N. 

4. The obsorvations which have thus been detailed should be repeated 



48 



TERRESTKIAL MAGNETISM. 



[Sect. II 






^■^ 



whenever the ship has so materially changed her geographical position 
as to have altered the magnetic inclination 30° or 40°, or whenever she 
has been refitted, or has undergone any other change which may hare 
made a coi^siderable alteration either in the amount or in the distribu- 
tion of her iron. It is also particularly desirable to repeat them if the 
ship should be in a harbour where the inclination is very small or 
where it is very large; ar-d finally^ they should be repeated without fail 
whenever the magnetic observations made on board a ship are broueht 
to a terminationj and before any change has been made in the iron of 
the ship. 

5, If the positions in which the standard compass and Fox's ap- 
paratus are used on board are not very far from each other, and if there 
is no iron within a few feet of either of them, it will usually be found 
in sailing vessels built of wood at least, that the effect of the ship's iron 
is the same, or very nearly so, in the two positions. To prove this^ place 
a second comp.,.3 (which, like the standard compass, has had its index 
^rror, if any, determined) in the gimball-stand of the Fox's apparatus, 
and observe, generally, whether the two compasses agree when the ship's 

head is on the different points, and especially on the points of greatest 
and least error. 

G. When the observations thus described have been carefully made 
and recorded, they furnish the means of calculating approximately all 
the corrections required to clear the magnetic observations made on 
board the ship, in her successive passages from port to port, from the 
effect of the iron upon the needles of the standard compass and of Fox's 
apparatus. 

The calculations for this purpose have hitherto been made at Wool- 
wich, by formulse derived by Mr, Archibald Smith from the fundamental 

r 

equations of M. Poisson's theory, in his ' Memoire sur ies Deviations de 



e 



a/ ' 



la Boussole produites par le Fer des Valsseanx/ 

For the full understanding of these fornmlse, it is necessary to read 
Mr. Smith's notices printed in the accounts of the magnetic observations 
made in the Antarccic expeditions of Sir J. C. Eoss, and of Lieutenants 
Moore and Clerk, published in Nos. V., VI,, and Vill. of the Memoirs 
entitled 'Contribution^ to Terrestrial Magnetism,' in the Philosophical 
Transactions ; but it may h^ convenient to reprint here the formulse 
which sre of most general application. In these formulae, symbols are 
used which have the following significations: .^ is the ^tolal magnetic 
force of the earth observed on shore; 6 the inclination observed on shore 
by Fox's apparatus; j,' the true magnetic azimuth of the ship's head 
counted from the magnetic North, positive when her Iiead is West of North 
and negative when East, rj/, Q\ and C^are the same elements observed by 
the needles of the sta^idaid com.pass and of Fox's apparatus on board ; 



S !■«» *'" 



lli 



7 



For 



the CO 
be CO 



i 



-1^ 



mp 



,,ey may ^ ^ 

jefignated by 
v'r\ it re^"' 



, lias been o 
values of 5 at a 
of these values i 
totheT;.:'-ard 



and ail .--■- Ji^ 
"'^'t be attend. 

A= ■ 



B 



+ • 



+ 



1 

^ 



( 



+ ■' 
+ •( 



6 



D 



•i 



E 



» 



i 



J^tfc 






^ 
^ 



^v 



*^. . 



1 

i 






-V ^_ -, 




K . 



!^P5iical .„ 



or^ 






■^wVr 



^^U t,^ 



ft . 1 






IS >, 



er^ - 



'T_ 






<-«u 



n. 



IKS 



uy, 



- ^4 , ; 



'^^er.acdift^'. 



^ * 



** U^ 



nbas b 



tf *^^ 1 



■^ 



aa r. 



• nrsapi 



WA-t\, 



R 



of 



Appendix.] 



TERRESTRIAL MAGNETISM 



49 



C—(=id is the deviation or error of the standard compasb caused by the 
ship's iron when her head is on the point C ; and finally A, By C, D^ E, 
c, d, and A', are coefficients to be employed in calculating t)ie cor- 
rections applicable to the magnetic observations of the declination, 
inclinatioBj and force made at sea in any part of the globe. 

7. For the corrections of the declination A, B, C, D^ and E are required ; 
they may be computed by the following rules : let the 32 points of the 
compass be nostbered from 1 to 32, beginning with N.byv\\rrl; 
N. N.W.— 2, &c., and going round by S.=i6. to N.i=:32; and let the 
deviations observed on the diflerent points, when the ship is swung^ be 
designated by 5 with the number attached which shows the point to 
which it refers : as for example d^ will be the deviation at N. by "VV. ; 
§2 at N. N. W, ; 5,6 at South ; and §33 at North. Then, if the devia- 
tion has been observed on the sixteen principal points, we shall have the 
values of 5 at all the even-numbered points, as d^, -5^, §^,, &c, to ^33 ; and 
of these values all those in which the North end of the needle is dra-^^n 
to the westward by the ship's attraction will have the sign + prefixed: 
and all those in which it is drawn to the eastward the sign — ; the si^ns 
must be attended to in making the additions which follow : 



Y -_ 



caret u.' 



". *-- 



3 ^ct 

liservations 1 
- -♦ ^« port, f- 



B= -0478 (its log 



2-6800) 



{h 



/ 



+ ai55 (its log 



+ 1(5 



8 



^24)' 



1^0625) 



ih 



+ s ^ 



mJ 



^30 + ^14 ^ ^is], 



+ ^0881 (its log = 2-9464) { a. -- S^g + 5 



i& 



S 



26 



d 



10 






■lie at 



r" 1 



J ' -I 



jSttT 



"isai; 




vii:.^'5 

the ^ ■■ 



ID 



V 



.1 



'vr 



forfli 



ul-' 



'.'M 



IS 



tbe w- 
obsef ^ 

.. of '^^ ■ 



.»^ 



h 



\ 



-.elf 



T ^ 




/ 



C = -1155 (its log = i'0625) {n^ + -5.,, 
+ '0384 (its log =¥^9464) {5. 4- 5 



+ '0478 (its log --r: 2^6800) {§5 + S 
+ I (5a2 - 5ia). 



26 



'26 



D = -0884 (its log = 2-9464) {t, - ^^o 



6 



e 



5. 



26 



5.0 ^ 



+ ' 



5 



{5 



5 



sa 






E 



8 



6 



s 



10 



5. 



22 



+ 1 {5.« + 5 



16 



5o- 



} 



K^t* 



B 



l4 



B 



12 



B 



iO 



^ibI? 



B. 



•20 i ? 



^^}f 



^u + ^m + 



0884 (its log = 2-94C4) {d. + ^30 + ^u + ^ih 



If the deviations are greater than 7^ or 8°, the sines of the a^^les of 
deviation should be used in the formuhe instead of the angles themselves. 
Where time will not allow of observations being made on the ^'^tcen 

D 




50 



TERRESTRIAL MAGNETISM. 



[Sect. II. 



^w^ 



m 



^ ■ - 
■J 



principal points, they may be confined to the eight principal points. If 
tiiose observations are carefully made, the results derived froni them 
•will have nearly equal value with the results derived from observations 



J ^' 



maae ou 



fonaul 



for calculating A, B, C, D and E become much simplified. Using the 

before, and 5, Sg 5^^ S,^ 5,o 5^^ S,g and 5^ being the 



same notation 

eight deviations observed, we have 



A 
B 



J ih + h + Kz+ 5,s + 5^0 + hi, + »28 + 5^} 
•1768 (its log = 1-2474) {s, - S^ + 5,, - S.J 



+ i{s 



02^: 



.\ 



c 



1768 (its log = 1-2474) {b, + S^ 



S 



ijt 



D 

E 









K) 



n 



iS 



s 



12 



} 



i{s 



32 



+ §16 



S 



§^} 



The ..._mcients being known, the deviation on any point of the compass 
may be computed by the toll owing equation : 

sin 5 =r A + B sin C' + C cos C + D sin 2 f + E cos 2 f. 
A, D, and E may be expected to remain constant, or to have the same 
values in whatever part of the globe the ship may be, whilst uo material 
alteration is made in the distribution of her iron. They may, therefore, 
be regarded as determined, once for all, by the deviations observed 
when the ship is first swung, though they may possibly be obtained 
more : ctly by taking the mean of the values obtained on all occasions 
when that process is repeated. B and C are variable, and depend on 
the dip, and aisc on the proportion of the iron which changes its mag- 
netic stat-e cotemporaneously with changes in the geographical position 
of the ship, to the permanently mag>ietic iron, or to iron of an inter- 
mediate quality to ihe two which have been named, and of which the 
magnetism is neither permanent on the one hand, nor, on the other, are 
its changes cotemporaneous with changes of the dip, but are consequent 
ou such changes, and require a greater or less interval to conform to 
them. It is on account of the uncertainty of the law according to 
which the^c: two coefficients B and C vary in different ships, that when 
a ship has changed considerably her geographical position, it is desirable 
to repeat the process by which the values of the coefficients may be 
re-deterniincd ; and that it is still more desirable that a full and suffi- 
cient trial should be made of a very simple method suggested by Mr. 
Arclr-ald Smith, in No. VIII. of the 'Contributions to T.irestrial 
Magnetism,' for djjrmining the variable coefficients at anytime that 
may be wished, either at sea or in harbour, by deflections of the 
Compass-needle with the ship's head successively on aay two opposite 



r - fit 



C 



o^f" 



con 



Vv* 



U 



serve 
only s 



i 



sU- 
observ 



and th( 



S] 



in whi 



;iul 






by the 

tion of 



« B 



reqmn 

tables, 
follow i 

of the * 

Let] 
"0 mul 

45^ an 



- ^ 



-. H, ■_ _ 



^ 



^. 






Q 



a1 






'.lUs . 



6 1 



Appendix. 



1 



TERRESTEIAL MAGNETISM 



1 



points of the compass. By the addition of a brass bar attaelied at right- 
angles to the prism and si^/* t-vane of the asimuth ring of the standard 



comn-assj a ^'. Meeting ma.. .A or magnets may be leniporarily fixed at a 
conveni ..t disti?5ce from the conipass-needlej and the deflection ob- 
served -with the ship's head on opposite points by a process requiring 
only a very few minutes, and independent of the visibility of the son or 
stars, or of any distant object. If the points taken be those which the 
observations in harbour have shown to be points of no disturbance and 
if Vj v^ be the angles of deflection on the respective points 



fe 



^r 



-«.! 



V^ 



i ' 



A **. 



na. 1. .';- 



IIP*' 



lybe 



O a. 



t * 

1 






t 



I 



^ \ 



% 



f. 



J t- 



r --. 



iQu 



ii^ 






. i 



kr. 



'-'* 



i>'' 



1. 



'. - 



A^' iT 



1 ^. 



^J 






..Ai 



I 



V 



f B^' + C^ 



sm L'l "»- sin y 



^, 



sm i?! + sin i\j, 
t;j — f^ 

tan -^ — ^ 

2 



tan 



^'i + v^ 



2 



and the deviations on the several points may be computed bv 



sin 5 



Jb^ 



sin 2 C^ + E cos 2 C: 



in which a is the easterly azimuth of the line of no deviation. 

Should this method of determining the variable part of the correction 
formula be found to succeed ou trial, the correction of the disturbances 
by the officers of a ship might be still further simplified, by the forma- 
tion of tables of each term for every probable value of the coefBcio-itSj 
requiring merely the addition of the quantities to be taken out from the 
tables. In the meantime the calculations may be facilitated by the 
following table, extracted from Mr. Smith's Memorandum in No. YUL 
of the * Contributions to Terrestrial Magnetism/ 

Let Bi, Bj, . . . , B;, Ci, C^, . . . . Cj represent the values of B and 
C multiplied by sin 11 o 15', sin 22^ 30^ &c. ; and let D,. D,, D,. E^ 
E„ E, represent the values of D and E multiplied by sin ^2'^ 30' '^ia 
45^, and sin 67^ 30' j we have then-^-^ ' ^ 



a 
5 



32 



A + C + E 



16 



A 



C + E 



5i 
831 



A + B, + C, + D, + E, 



A 



5 



B, + C, 



IS 



S 



17 



s. 



A +B, 

A - Bj 

A + B, 



C 






E, 
E, 



Cr + D, + E, 



S 



S 

s 



30 



14 



18 



A 



B. + C, 



A + B 



A 



B. 



C. + D^ + E^ 

- I>4 + E, 
Cb - D, + E, 

Co + D, + E^ 



d2 






^ 



52 



TERFtESTRIAL MAGNETISM. 



^ 



[Sect. II. 



\ppei 



-3 






^3 - 


= A + B3 + C5 + D« 


+ Ea 


^w- 


= A - B3 + C5 - n 


+ Eg 


^13 = 


= A + B3 - C, - D, 


+ Ej 


^19 = 


= A - B3 - C5 + D, 


+ E2 


84 ^ 


= A + B, + C^ + D 




5^8 = 


= A - B4 + C4 - D 




h,'- 


= A + B4 - C4 - D 






- A -> B^ - C4 + D 




55 = 


= A + B5 + Cg + Dg 


— E2 


^'27 ~ 


= A - B, + C3 - De 


-E, 


Sn = 


= A 4 Bj ~ Cg — Dg 


-E, 


^ei = 


= A - B5 - C3 + Dg 


-E, 


86 = 


= A + Be + C2 + D^ 


-E, 


5gQ = 


= A - B« + C, - D4 


-E, 


8]0 - 


= A + Bg - C2 - D, 


-E, 


5«r = 


= A - B« - Ca + D, 


~E, 



8, 



i5 



A + B, + Ci + D^ 
A - B7 + Ci - Dg 

- C. - D, 



A + B7 



S 



23 



A 



B7 



c, +n 



E 
E 
E 

E, 



6 



(5 



6 






A + B 



24 



A 



B 



E 
E 



f 



If the aKgles are greater than 7° or 8°, these fbrmulse give the sines of 
the angles of deviation instead of the angles. 

8. For the correction of the inclinations observed at sea the co- 
efficients c and d may be computed from the disturbances on the several 
points, shown by the observations of the inclination with Fox's apparatus 
when the ship was swung in harbour, by the formula : 



ccos f + Jtan 9 



(1 



D) sin ^cosec C tan 6^ 



for all other points than North and South, and "with the ship's head 
North or South, by 



c 



(cos C + B) sec ^ tan d^ ; 



ohserving that the v^ilues of ^ employed should be calculated by the 
declination-coefficients. With the values of c and d thus obtained, 
tables for the correction of the inclinations observed on different courses 
at sea in all values of may be computed by the formula : 



tan 



/?/ 



e 



CI - D) 



. (cos C T d tan d) sin C c^^^ec C 



obsen 

is pea: 
lated 1 

sea, «a 
of the 
the di 



shore 



J 



tailed 
of the 
forma 



the fiti 

the im 

10. 

gimba 
at the 
ixiaj b 
obser - 
andD 
no dis 
coeffij 
tioa 

defler* 
the 







mt 



\ppendix.] 



TERKESTiilAL MAGNETISM 



53 



ic 



ea t 



-"' u. 



sli- 



hS 




i 



or tan ff — c 



d 
cos C + -- tan 

COS C + B 



cos C ' 



! 



obserYing that the first must be used when the ship's course is l>etween 
N^ E. and S. E., or N. W. and S, W, ; and the second when her course 
is nearer the N. and S. points ; and that the values of ^ should be calcu- 
lated by means of the declination-coefficients, 

9. The coefficient A', for the correction of the intensities observed at 
sea, may be computed by the subjoined formulse, from the observations 
of the intensity with Fox's apparatus on board with the ship's head 
the different points, compared with those of the same instrument on 
shore, and witu the absolute value of the tc^tal tbrce on shore (jf) ob- 
tained in the manner described in App. 3. Tables for the correction 
of the intensities observed at sea may also be constructed by the same 
formulae ; 









A> 



sin ^ = c cos 6 Qos ( + d sin 0, 



/ 



or -TT— cos 0- sin C' 



(1 — D) cos B sin ^; 



the first to be used when the inclination is large, and the second when 
the inclination is small. 

10, If the disturbances of the compass-needle, at the spot where the 
gimball-table for Fox's apparatus is fixed, differ materially from those 
at the spot where the standard compass is fixed, the standard compass 
may be removed temporarily to the gimball-table, and the deviations 
observed on the eight principal poiiits, which will give the values of B 
and D for that spot, as well as determine the points on which there is 
no disturbance : if these are opposite points^ the value of the variable 
coefficient B can always be ascertained experimentally for the correc- 






"j-J 



It? 



r 



tion of the observations of inclination and intensity, by the angles o 
deflection produced in a compass-needle placed on the gimball-table by 
the method described in 7, p, 19. 






■^' 



*T 






( 54 ) 



[Sect. II 



Section III. 



HYDROGRAPHY. 




Y CAPTAIN P. W. BEECHEY, K.N. 



r 

Milking a Passage. 

The observer's attention is directed first to those objects 
which aiFe<;t the passage of a vessel from one part of the 



jlobe to another ; such as the movement, the duration, 
the limits, and the periodic occurrences of those gi-eat 
currents of the atmosphere and of the ocean, upon which 
the speedy and successful issue of a passage mainly 
depends. 

Well recorded and established facts bearing upon the 
several points connected with these inquiries are highly 
irniortant to navigation, and m.ay be collected by every 
assiduous seaman in the ordinary course of his duties. 



1. It is well known that in various parts of the globe 



there exist monsoons, and zones of trade and variable 

and other disturbances of tli. 



wind 



" ; and that these 



atinospheru which influence the surface of the ocean are 



the 



principal causes of the many currents which sweep 



over the face of the earth. The 



1 



.se upon a 



Tessei passm 




of 



• » 



quiries a seaman 



r\ 



(wind 



'J 



rent) perform an important part in the economy of nature 



I 



i 



Sect 



an a' 

note 

coim 

any 

natcM 



sa. 



e 



w 



hil" 



any 
usua 
advii 
such 

2. 

tion 

com] 

be c 
mine 
ship' 

once 
ing 

the] 
tion^ 

atai 

in 0] 

com 



ive 



for 
all 

obvi 

ente 




^ 

41 



Sect. III.] 



HYDROGRAPHY* 







1 • IJ.- 



J 



ut 



u- 



b -"'^ 



F 

i 



^ 






1 



0{X 



f 



t"^- 



i - 



?e, 



an additional interest attaches to a correct knowledgs 



■■^ 01 



them. The su-iraan should therefore not only carefully 
note the direction and force of the winds^ but should 
connect with such entries notices as to when and where 
any continued or periodic wind commenced and termi- 
nated : what was its strength and effect upon the pas- 



came on suddenb^ 



J5 



and was furious 



sage; whether it 
while it lasted, or otherwise ; whether It was preceded by 
any particular symptoms, and whether it was such as 
usually occurs at that season ; and lastly, w^hether it he 
advisable to cross this wind in any particular direction, 
such as close hauled or large, &c. 

2. To detect the current, a more than ordinary atten- 
tion must be paid to the reckoning of the ship : the 
compass by which the course is steered should occasionally 
be compared with that by which the variation is deter- 
mined, in every position of the ship's head :* and the 
ship's place should be determined by observation at least 
once a day. Sights for chronometer morning and even- 
ing should both be referred to noon, at which time 
the latitude will of course be observed ; and all observa- 
tions for latitude at night, or for fixing the ship*s place 
at any time, should be referred to one period of the day, 
in order that the position of the ship bi/ ohservation^ as 



Dead 



may 



give the direction and force of the current, if any, 
for the twenty-four hours. These observations should 
all be entered in a table, and at the close of certain 
obvious and natural periods of a passage, such as that of 
entering or emerging from the trade-wind, the calm lati- 

* See Section * Terrestrial Maa:netism; 



I- 



56 



H\ DROGR APHY. 



[Sect. III. 



Sect. 



] 



S 



s 



tudes, the commencement or termination of the monsoon, 
of any positive change of current, or from any continued 
state of things to another, the whole effect of the current 
for the period should be deduced, and an average of it 
daily rate and set be given, together with any remark 
which may be considered useful. 

3. With the direction of the current thus determined, 
it is very desirable to connect the temperature of the sur- 
face of the sea, for it has been by such observations that 
we have been able to trace, with a certainty amounting 
almost to proof, the continuous course of the same body 
of water for thousands of miles over the troubled surface 
of the ocean, and that other curious and important facts in 
physical hydrography have been ascertained. We would 
therefore urge attention to the subject as one of con- 
siderable importance to navigation. As a proof of its 
influence upon a passage, we need only 
remarkable phenomenon of the Equatorial and Guinea 
currents : two streams in contact, but flowing in opposite 
directions, and having a temperature differing 10 or 12 
degrees from each other, and yet pursuing their opposite 
courses for upwards of a thousand miles ; and according 
as a vessel is placed in one or the other of these currents, 
will her progress be aided or retarded from 40 to 50 
miles a day.* 



instance the 



Cou 



J. 



t/^ -^ Vi'*--^ *hj ^/ %^ J.AM, mj \^JL «.fVV Vt* ^-' *^ * 

the surface of the sea jfrom every ship in active service, 



we should be able in a short time to construct tables 
showing the normal temperature of the surface of the 

every 5° of latitude for every month in the 

* Sauiiic's * Hydrographical Notices.' 



ocean lor 






1 






> 



year 

parti' 
differ 
canst 
oiarli 
teat 

tardii 
and i 
lead 
chan^ 
where 
over i 

It 

curr.. 
and i 



houi 



x/^ 



in the 



mad 



e 



lie'- ' ( 
4. ■ 

tile oc 

appea 
floati 



V\ 



oflers 



"It 



> 



Mf 

Moving 
* Co 




Sect. III.] 



HYDROGRAPHY. 



57 



y^'* 



c 



1 y 



w X 



i uf .-' 



:e ti: 



f 



I 



1/ ;. 



'Pr 






^ * ^ 



I ■ 



^.n 



Mif: 



.■1 J ' 



T\ 



„^ 



i'' 



t; 



a 



of 



■:d 



lU • 



;>^ 



year, and a comparison of these with the actual tempera- 
ture of the surface at any particular spot, and in any 
particular month, would at once manifest an abnormal 
difference, if any existed, and lead to a knowledge of its 
Cciuse, which might prove of considerable use to the 
mariner by acquainting him with the movement of the 



great body of water in which he was sailing ; either re- 



tarding or accelerating his progress as the case might be, 
and at all events affecting his reckoning. Or it might 
lead to a closer determination of the limits and periodical 
changes of currents which, as before observed, are every- 
where running over the surface of the sea as rivers run 
over dry land. 

It is therefore recommended to add to the table of 
currents a column for the temperature of the open air, 
and another for that of the surface of the sea, which 
should be registered frequently during the twenty- four 
h<^urs ; but as such observations form an essential feature 
in the meteorological register of a voyage, they should be 
made at the times and in the manner indicated under the 
head of Meteorology.* 

4 There should also be noted in the Eeixiark column 
the occurrence of masses of sea-weed, or of any continued 



any 



other 



appearance even of small patches of this or -; 
floating substances which may be seen ; and if opportunit} 
offers, deep-sea soundings should be tried at the spot. 
" It were much to be wished,'' says Humboldt, ' Person. 

* If pasdng Cnpe Horn, or through seas where icebergs may be 
moving about, these observations cannot be made too frequently in thick 
weather, especiaUy as a precaution, for the water appears to be influenced 
to a considera'' . distance around these masses, particularly in their 



wake. 



d3 




-r^^w. 



5d 



KYDROGRAPHY. 



[Sect. III. 



Nar/ vol. ii. p. 11, " that navigators heaved the lead 
more fretiuently in these latitudes covered with 



Dutch 



weeds, 



!S 



of 



O 



N 



coa=-t of Scotland by using lines composed of silk thread." 



F 



In many places, 






he Pacific especially, the tern are useful monitors of an 
approach to those low specks of coral which endanger 
the path of the navigator through tlie labyrinth of the 
great South Sea. In short everything that may seem to 
the voyager to be interesting or new, or likel) to be use- 
ful, should fxnd a place in the Remark column.* 

At the end of the passage a summary of these remarks 
should be given, the whole effect of the current for each 
particular portion of the passage recapitulated, such as 
that which was due to the N.E. or S.E. trade-wind, or to 
the monsuon, as the ease might be, and distinguishing 



occurr 



:e 




calm latitudes or durin 
a period of variable winds, or otherwise, averaging the 
daily rate ; and then might follow any remarks you may 
wish to make either upon them or upon any other feature 
of the passage ; together with any directions or hints which 
might be considered useful to those who should follov. 
ovei* the same ground; such as whether any advantage 
would have been gained by steering more to the east or 
west, or in any other direction ; whether any time would 
have been saved by making the land on any other bearing 
than th.U: in which you hit upon it ; and in short any 
remarks which would be instrumental in conveying to 

* Fvr the form in which these observations may be tabulated, see 
Appendix, Table I 



e 






sd 







ther 



ses^: 



5. 

of th< 

luissi 
f th' 
houl 







facto 



i>a 



tei 



M 



rAt- A1 



glODi 

But : 

conti] 
endct 
appi ^ 



1 f^ 



atta:] 



'1 . 



T 

theC 



u 



-ii j 



mt! 

swev 



n- 



t .^'^ 



) 






Sect. III.] 



HYDROGRAPHY 



5 



a 



*i 



^\ 



others information which you would have wished to pes 
sess yourself at the outset of the passage. 



( 



I 



1 



V 



u 



i.. 



C-A4^ 



B % 



'f 



i 



.. '* 



^P4li' 



1- r 



* ' 



er 






.hor 



i 



CurvenU 



s 






* 



5. It is \^ery desirable that observations upon the course 
of the waters of the ocean should be made vvithout inter- 
mission ; and that a continued register of the temperatur 
of the surface, and occasionally of its submerged btrata.'* 
should be kept, as it is only by numerous well-recorded 
observations of this nature that we shall ever be able satis- 
factorily to define the limits of the various zones of movin 
water which sweep over the face of the globe, mindiir^r the 





waters of the Polar Seas with those of the equatorial re- 
glonSj and even affecting the clLaate of extensive districts.f 
But if from various causes a connected series cannot be 
continued throughout these great currents, at least an 
endeavour should be made to commence a register on 
approaching the limits of such as are now 




defined, and to continue it while any interest appears to 
attach to the subject : such as that of the Gulf-stream ; 
the Trade-wind drift ; the Guinea and Equatorial currerit ; 



the Cape of Good Hope current, blending with the south- 
east trade drift ; and the Brazil current — in the Atlantic ; 
the Mozambique and iVgulhas current ; the Trade drift ; 
and monsoon current of the Arabian and Bengal gulfs — 

Ocean* The remarkable Peruvian current 



Indian 



sweeping along the western coast of South America ; the 



By means of self-registcnng therniomctcrs, properly set and care* 
fully lowered and as carefully hauled in (without jerks). 

t See Humboldt on the Climate of Peru \ ^Sabine on the Ciiinate of 
St. Thomas Island* &c. 



60 



HYDROGRAPHY. 



[Sect. III. 



...t. IJ 



Seo 



Trade drift, and Equatorial current ; the Mexican current, 
passing along from Panama to the Gulf of California, 
according to the monsoon. The counter- currents north 
and south of these, and the moving belt along the coast 
of Japan and Corea to Kamtchatka — in the great Pacific 
Ocean ; particularly noting, as of great importance to 
navigation, the limits of the outer currents around the 
Cape of Good Hope and Cape Horn, all of which will be 
found on a small scale delineated in a eeneral chart at 



CO 



tlie end of this paper. 

Some of these currents maintain a constant difference 
of several degrees between their own temperature and 
that of the mean state of the water about them, and all 
observations which can throw light upon this subject, and 
upon the limits, course, and velocity of the stream, will 
be most acceptable. 

6. In ]jassing through any of these great currents, the 
observer should carefully define the extent of the belt of 
moving water at the parallel in which he crossed it ; the 
irait of the eddy on either side of it ; determine the rate 
and set of both ; carefully note every barometrical or 
therm.ometrical change of the air, or alteration in the 
temperature or specific gravity of the sea, and if possible 
the depths to wMch these temperatures extend; and 



record all appearances and changes which may app-^-u- 
of interest or seem to be useful to those who mav follow 



over the same ground. 




To detect the motion of the stream the remarks in 
Art. 2 blvmld be attended to, with the exception that 



here 



be/ 



ascer 




during the day by astronomical observation, and 



*' 



r- 



the 
Tlie 







the be 
the >- 
occup] 
fthe 

aod of 







A r 



'i'/l 



>' (r-.' 



the pi' 
sea-wt 



7. ( 

" maki 
the 0^ 



of 

Buti 



n 



it 



A 



of th 

metboi 

if po 

six h 

stream 
this ^^ ■ 

4 

^^ has ; 

stray 1 




the 



5 



An 



CO.. 



r_ 



r^ _ *>^_- 




r 



. n- 1 



1 



.\ ^ 



.? • 



■^v 



1 « ^ 



> . 



I 



1 1 



■■> 



^r 



? M 



- i 



-.5 



t ^^4 -4 



M^ 



» V 



1 



it: 




1 m 



1 



^ 1 



\ ' 



t 



L; III 



..> 



1 



i 






P 



'■ 



J 



Sect. III.] 



HYDROGRAPnY. 



61 



the course and rate of the current deduced for short 
intervals of time instead of for the twenty-four hours. 
The ohservations should commence previous to entering 
the body of moving water, and be continued until after 
the vessel has quitted it, when it will be advisable to 



occupy a page of the journal with a graphic delineation 



of the several courses of the stream, indicated by arrows, 
and of the several stages of the vessel's progress by the 
various temperatures which have been observed, noting 
the places where ripples were seen, or where drift-wood, 
sea-weed, or other floating substances occurred. 



The Stream or Surface Drift. 

7. Currents have been spoken of under the head of 
" making a passage," as they affect a ship's route across 
the ocean, and may have been determined by the position 
of the sbip by DR differing from that by observation. 
But it will be proper further to try the set of the surface 
of the water on all favourable occasions, by the ordinary 
method of anchoring, or of sinking a weight, endeavouring 
if possible to get observations on the same day at about 



six hours apart, in order that it may be seen whetlier the 
trcam be due to a tide or not. If the ship be in sound- 
ings, and the day be calm, a very sim.ple way of effecting 
this without the trouble of either anchoring or lowering a 
boat,* is to drop a heavy lead from the quarter, and after 
it has reached the bottom, to run out a small quantity of 
stray line, and then make fast the " nipper," or a billet of 
wood, to the line ; and at the same time to fasten the end 

* An objection to trying the current in a boat is the uncertainty of 
the compass. 






tj- X — 



62 



HYDROGRAPHY. 



[Sect. Ill 



of the log line to it, and veer away both together.* Tlien 
mark by a watcli the time each knot is in ruimino- out 



buoying up the lii 






a chip of wood ; when all the 



line has rim out, take the bearing of the nipper by a 
compass, imd haul all in together. If currents be tried 
when there are no soundings, the result is merely the 
relative motions of the upper and lower strata of the Mater, 
and it would be difficult to say which way either 



were 



oing ; but if we can possibly determine by astronomical 
observations the course of the upper surface, we shall 
thence be able to deduce the set of the lower ; and if there 
be found any difference of moment, it will be very desirable 

of both upper and lower 
strata of the water, and to record them with the other 



to ascertain the temnerature 



These 



observations. 

made on calm days, and th 



observations ought always to be 



j^j 



greater 



the weight be sunk, the better. Bottles thrown over- 
board with a label inside. 



and lonff. 



5. of the spot where c;xb 



containing the date and lat. 



5t into the sea. afford 



ready means of detecting the current if picked up after 



wards, and ships would do well frequently to expend a 
few empty bottles in this way.f In the event of meeting 
any such drifting at sea, they should be picked up, their 
contents copied, and the date and position of the spot 
added to the label and carefully resealed, they should 
then be returned to the ocean, and a copy of the label 
forwarded to the hydrogTapher. 

* If the lead-line be not hitched to the nipper, the tide may drag the 
line through it, and there will be no result. 

t The bottles, before sealed, should be ballasted ^ith a little dry sand, 
consohdatea at the bottom with bees'-wax or pitch run in, that the bottle 
may be Itept upright and not swim too light. 



h 

I 



f 






i 



Sect- II 



8. 

the dr 
one * 

or a^ 

time 1 

noting 
Sue 



cumst 



%J 



ever 1 

sliouk 



. ■ 



times 



or vr 

lions : 

will ^ 

Laic ^. 



V 



i-vv i.--. \J 



portai 
of the 

of h.^. 

Outgc' 

iti 

^ater, 



\ 



-'a 



le 



Tl 

fefern 
probe,' 
and tl 



one 



0: 



the t:. 





III 


^ 




i 

* 


41 






■a 


tl. 


be t 


k 1. 

,' a 

1 

4 



■J 



1 



J 



V 



^*V' 



K 



■^ i 



L 



iiti 



lAWj 



1 * 



t 




:to' 



1 • * 



A r, 



^ * 



I' 



f^ 



^^ 



V^ 



!* 



k\ 



1 



JJ 



!oHel 



dry 



i^ 



sJB''' 



■i 



Sect. III.] 



HYDROGRAPHY. 



6" 




8. If near to any shore, a few points of which are well 
fixed, and the water he found too deep for anchorage, the 
course of the stream may still be ascertained by notin 
the drift of a float — a plank, for instance, weighted at 
one end, so that the other just floats above the surface ; 
or a weighted lo.reca^ — fixing its position from time to 



time by angles taken in a boat at the several places, and 
noting the intervals by a watch. 



Such methods may of course be resorted to when cir- 
cumstances do not admit of greater accuracy, but when- 
ever it can be done, the course and rate of the stream^ 
should be observed every hour during both tides, and the 
times of slack water carefully noted, by anchoring a boat 
or vessel. Upon an open coast one set of such observa- 
tions made here and there, well clear of the headlands, 
will be sufficient ; but in chaimels and straits in which the 
tide enters at both extremities the tidal phenom-cna are so 
varied and full of interest, that it becomes highly im- 
portant^to spread the observations over as large an extent 
of the channel as possible, and to pursue a regular system 
of hourly observation throughout both the ingoing and 

outgoing stream.s. 

It is desirable to know at each place the time of slack 
water, the direction in which the stream turns, and the 
rate and course at wliich it runs during its several stages. 
The stations should be numbered, and the times all 
referred to one meridian. In such channels there will 
probably be one or more places where the stream.3 meet, 
and there of course observations v>dll be made ; and as 
one of these places will probably be the virtual head of 
the tide wave, it may so happen that the time of the high 



I'O^ 7^—^^fy- 



-■>, -'^ - 



■*ojsr=r 



64 



HYDROGRAPHY. 



[Sect III. 



S 



and low water there hy the shore will govern the turn of 
the stream either along the whole channel or until it 
reaches a spot where another meeting of the streams 
occurs. In such a channel also it will prohably be found 
(as in the Irish Channel) that the same strelm make, 
high water at one end and low water at the other at the 
some time ; so that the observer must entirely divest his 
mind of the too often mistaken notion of the turn of the 
stream being governed by the rise and fall of the water 
in its immediate locality. As our space does not admit 
of further detail, I shall leave the subject in the hands of 
the observer with a remark which, whilst it will put him 

f observations are required, 



m possession of what kind 



will at the same time I think insure his interest in the 
subject and his hearty desire to co-operate in the matter. 
In the « Philosophical Transactions, 1848,' Part I., it 
has been shown that in such a channel as that above- 
mentioned there have been discovered two remarkable 



spots 



u 



velocity witliout there being any material rise or fall of 
the water by tlie shore, and in the other that the water 
rises and fails considerably without tjiere being any appa- 



rent motion of the stream. 



Such phenomena are highly 
curious, and worthy of all the attention that can be 
bestowed upon the observations. In tracing them it is 



mam test th"^ 



cHj 



they 



are intimately connected with the 
height and progress of the tide wave along the shores of 
iha channel, but this properly belongs to another section 
(see Tides). 

9. Passing the mouths of 



Amazon, th 



great 



such as the 



, tiie river Plata. Orinoco, Mississippi, Zaire, 









> 



\ 



1 



^ct. Ill-: 



Sene; 



■al 





a 



The 



fiuence 



0\ 




liim^elf 



oft 



>iiV.- 



might e, 
of this 
courses 

it, and 



angle 



IV. 



accordin 
Tliel 

been gl , 

of the J 



1 ' 



\ 



have \k , 
of the ' 

hmits, 1 

place*, . 

havin 



. * The I 

^■- 300 te ; . 

^' hour, 
nearly f^ 



/ 



u> 



^. 



n 









^C 



.^ 



1 



(-' 



1 * 



a iJi 



le ir-^i . 






■i ui 






ill 



_*jlU 



D 






J 



ii 



o^iriVP 



. .-- n 



4 .*-» 't^ 



,1U-''^ 



• ItUi of 






■■ 13 



1. 



1 -Xf 



., :0f 



the 



t*- 



^aire, 



Sect, III.] 



HYDROGRAFHY. 



65 



Senegal 5 Iiidns, Ganges, Yaiigtsee or Irawady, &c. &c. 



5 



observations on the stream should be more closely made, 
and dis colorations and specific iiravitv of the water noted. 




These and such like stupendous rivers extend then* in- 
fluence to a considerable distance from the coast,* and 
occasionally perplex and delay the navigator, who finds 
himself struggling against a difficulty, wholly unconscious 
of the cause and ignorant of the facility with which he 
might escape it by changing his route, f River currents 
of this description vary their direction according to the 
courses of the stream along the coast, by blending with 

it, and forming a curve, which vanishes only with their 
influence upon the ocean current ; so that we are not 
always to look for the outset from the river at a right 
angle to the coast, nor always in the same locality, but 



according to the prevailing o 




ir^- 



ug stream. 



The limits of the principal currents of the globe have 



been given (see plate B) in order to apprize the navigator 
of the places in which he should more closely attend to 
his observations. If, however, from any cause he may 
have been prevented continuing the series throughout any 

mts, and should desire to define their 
limits, he should begin at least a day's run from the 
places, and continue his register until he is certain of 
having passed the boundaries, attending closely to the 



curi 



The River Plata, at a distance of GOO miles from the mouth of the 
river, was fouud to maintain a rate of a mile an hour ; and the Amazon, 
at 300 m^es from the entrance, was found runniiig nearly three miles 
per hour, its original direction being but little altered, and its water 
nearly fresh. — Bennett^ Sabine, 

t See the effect of the Equatorial and Guinea current before-men- 
tioned, at p. 56. 



QQ 



HYDROGRAPHY, 



[Sect. III. 



temperatures ; for although limits have been assio-ned to 
these belts of moving water, yet they vary so° much 
according to season, and the data for defining them have 
hitherto been so insufficient, that it cannot be said they 
are known with any tolerable deerce of precision. 



In tbfi China Sea and among the islands of the great 

Archipelago the tides run strong and are°ery 

Lud observations are especially 



Indian 



indifferently known 
desired at those places. 

In the southern passages it would be well to try durino- 
the westerly monsoon, whether the equatorial current may 
not be found pursuing a subaqueous course to the west- 
ward, notwithstanding the surface current be found 
running in the opposite direction. 



Upon the east coast of North America, between the 
Gulf-stream and the coast, observations upon the set of 
the stream are also much wanted. 



Approachina a Coast. 



Wber 



in the ocean, the temperature of the surface of the sea 
should be more closely attended to, for it has been found 
in many instances that after a certain shoaling of the 



water 



the surface partakes of the temperature of the 



lower strata of the sea, which are in general colder than 
the upper. If such should be found to be the case 
always, and if from well-authenticated facts it should 

possible to fix zones of certaui temperatures about 
particular localities, the result would be highly useful 
to the navigator when out in his reckoning and perplexed 
with thick and ha^v weather. 




I 






ilM 



U- 



id 



H 






00 



eiit 



arkab'- 



mar 



^ 



niich t 



^-1 



known, t 
close iii 



asgi 



}U, 



U^*- 



- , .^ -^ - 



e ( 



10 shipi 

adverted 
aiid ca:\ 

two :i^.i 
to descri 

-"V -, I., 

1^ .it; C^^ 



dirr 



ii 



.-on 






'es ' 



-.a ; to 1 

giag ^1- 






ce 



■'^ 



^x 



11 



f 




% . 



1 V 



m.^ 



Ko 



■0 



•4 






.. '^ .' 



\ 



U\f^ 



■ '- ! 









^ ^ -*i 



W 






tb 



Ml 



f 



,1 



A 



. ..: of 



•e 







T 


..u 


^tbe 


nl ^'-''■ 


i-i <iri 



■T 



V ' 



fJif* 



^4 



^i*' 



1 



.4 



fcf 






1 






r^ 




I 



f. 



I 



'F 






t. TIL] 



HYDROGRAPHY. 



67 



that the general feature 



IL Hydrography requires 
aiid aspect of every country should be noted from the 
moment the hills rise above the horizon ; that all re- 
markable objects by which it may be recognised, and by 
which the position of any port or other locality may be 
known, eitLer at a distance when the weather is clear, or 
close in when haze or mist prevails, should be described 
as graphically as possible ; that the extent, direction, and 
outline of the coast ; its capabilities of aiFording shelter 
to shipping ; its dangers, or freedom from them ; its 
navigable rivers, harbours, and inlets ; and the objects 



Sailina D 






hould be fully 



and carefully recorded ; and here it is difHcult to avoid 
infringing upon what properly belongs to geography. The 
two sciences are indeed here so nearly allied, that it is 
scarcely possible to avoid encroacliing upon the province 
of the sister branch. The observer will, however, do w^ell 
to describe or delineate the character of the country as far 
as he can become acquainted with it ; the form and ele- 
vation of such hills as are visible from the coast : the 
direction of the vallevs and ravines ; and to mark the 
places where they pour their mountain-torrents into the 
sea ; to portray the bold topping cliffs, or low rocky pro- 



montories and their reefs ; the jutti'^g headlands or deep 
sinuosities ; or the low undulating country with its lag- 
ging streams and muddy or sandy fringe of coast; its 
shallows, bars, and deltas, each as the case may be ; with 
its lighthouses, beacons, buoys, and landmarks, stating the 



distance which tliey may severally be seen ; with even the 
forts, towers, churches, and silvery little clusters of cot- 
tages upon the inland elevations ; with such other varied 



68 



HYDROGRAPHY. 



[Sect, III. 



l^ 



features as the coast may present, and as may serve to 
convey a just idea of what may be expected to meet the 
eye of the navigator, or be required to keep him clear 
of danger, and to guide him in safety to his place of 



destination. 




At a distance there is generally some object more re- 
markable than another which may be singled out as a 
useful landmark. Note what it is, describe its appear- 
ance, and state in what direction the port, or any dantrer 
that may lie off the coast, bears from it. 

Should the coast be low, buildir 
first : large square houses or towers, church-spires, &c. ; 
any of these afford useful guides. Some localities may 
be distinguished in hazy weather hj patches qf white near 
the coast, such as masses of sand, chalk cliffs, &c., or one 
or more large white houses; and these, when viewed 
against the land or other dark objects, will occasionally 
afford excellent guides when all other objects are ob- 
scured, and at such timics are doubly useful. But avoid 
narks all lohite objects which have only the sky for a 

; such objects are seen only when the sun 
shines upon the surface presented to the observer, but 
utterly mil in ha::y weather, wlien they are wanted. 

bear in mind that no description can equal a 
tolerably faithful sketch, accompanied by bearings 
all your sketches take angles roughly, with a sextant 
between objects at the extremities of your drawing, and 
two or more interm.ediate ones, and affix them to the 
objects at the moment, and have at least one angular 
height in the picture ; let that be of the highest and 
most conspicuous or best defined object ; thus 



S;3 



back -ground 



Always 



T 



n 



f 






.. lll-l 




and let } 
1 • ^^ yon 

the sket^^t 



ci 



lally t 



tlip date • 
jr;(T mark. 

line a*- -'^ 



t-^ 




V 



H 



*'^^^. VX-'^-''^^ 



\^^^ 



o 



>> 



rsk 



12. B- 

ucptti 01 1 

iniporta 

aitecded 
which c 






cer 



or 



^^^(1 from 

approach . 

dete 









^ 

g 



I.. 



^ 



Tt 



! 



Uj 



m 



a 



ai 



c 



\ 



of 






t 



' a 



app 




r 



h 



V ^ 



' .:.n 



1 



tics n:ay 
., or -^^e 



vie .. . 



1 



wi* 



•1 



U' 



■J 

re ob- 



1 






.'a 



t 



l^.-i c 



.J. but 



, i 



( 



In 
.^ ill 



iSt 



.^ 



.^ 




.' rfUtt*- 



y 



,1 



U 



fc*' 



r 1' 









efe 



i 



Sect. III.l 



HYDROGRAPHY. 



69 



< - - - 5° 32' X S^ 58' 



Alt. lOZB' 



^ ^ 



- 5<^ IC 



^ ^dr 



V - - 5^ 30' - - 



J* 



<' ^ 






5-- 
^ _ 

V 



^ „ 10^'' 52' - - - 



X 



- - 7° 56' - ' - - > 

S. 33^= IC W 

Mag. 



j-'Toen 



and let your bearing refer to one of the objects b 
which you have measured angles. Always write under 
the sketch at the time the nome of the place, and espe 



ciallv the native name if you 



Ji^A 



possibly learn it, and 



the date ; and if you intend any of the objects for lead- 
ing marks place an arrow at the head of a perpendicular 
line above and below the objects ; thus 



>S 







""TfTiite. 



'n^ 




-iiiS;?'^""' 






'""^"'^'^^>^^c- 






sN-** 



--.* ^ 



_ ■•-> ^^v^i^ \->:A\^^^ 



Li.'lifho«se in one with East Teak of Mount Auckland, clears reefs in 4 fathoms, and 
" kept open (S. by E. ), leads through tlie passage, mid channel. 

12. Besides marks which are apparent to the eye, the 
depth of the water and the natm^c of tlie bottom are all 
important, and in all descriptions of a coast as well as in 



directions for approaching it, these are to be carefully 



attended to. State as nearly as possible the distances at 
which certain zones of soundings extend from the shore- 
and from what part ; whether the bottom shelves gra- 
dually or abruptly, whether the coast may be boldly 
approached, or more than ordinary caution be necessary ; 
and whether any peculiarity of the bottom may assist i 
determining a ship^s position or distance from the coast 
at night, or in thick weather= Always give your depth 
reduced to low-water spring-tides if possible,'^ and 
always give the least water upon a reef or shoal ; and if it 

* See page 81, Art 24, 



ii 






■ -.--T«^.--<-^v« - -'I^ 



70 



HYDROGRAPHY. 



[Sect. III. 



dries, state what water there is over it at high-water 
springs, and at what time of the tide it becomes dry. 

13. When nearing a coast, and at all times when at a 
greater distance from the shore in miles than the amount of 
dip in rmrmes due to the heighi of your eye, the height of 

mountains, or of other objects, may be determined with 
considerable accuracy if the weather be clear, and proper 
precautions be taken. To do this, if the distance of the 
object be not known, it must be found by measuring 
a, base mth the patent log. There are various methods 
-" m navigation-books for determining this p, oblem • 
shall therefore here merely describe the observations 
required to be made. At each end of the ba.P Tr,.n..„. 



given 
I 



# 



on ; and it one of Gary's double sextants be on board 
measure the terrestrial refraction by bringing the opposite 
horizons m contact with the arc both above and below the 
index, and then reading off each time, divide the differ- 
ence by 4 : this will give the dip and terrestrial refraction 
combined, which is the proper quantity to be allowed in 
correcting the observed angle.* 

In Raper's ' Navigation,' p. 90, 2nd edition, theme- 
thod of determining a ship's distance from an object by 
two bearings is briefly explained; and in Belcher's SSur. 
veymg ' it is set forth in a manner so clear and ample as 
to leave nothing to be desired : I shall therefore merely 
observe here, that accord 



observatioas and the 



value 



mg to the accuracy of the 



of the means adopted, will 



* If the terrestrial refraction alone he required, 
tny the true dip due to the heiglit of the eve, and 
terrestrial refraction required. ' 



take from this quan- 
the remainder i^ :he 



I 



I 



f 



Sect- 



IIlJ 



be 



the 



col 






shou 



Id, ii"? 
in the best 
the ol^^ct 



.,1-h 



that vi 
iU same tn 
distance ru 



r^." 



arc 0')Sv, v.- 
Hauled iu ^ 
^ ship sh( 



^v. 



operation, i 
and fresh b 

Two obst 
nations n 
With the 

may often 1 

^liencr/.l] 
^e^it and p 

^y it as o. 
•^^ --nt for 



^4. If l;. 



s. 



^ 



' -Ml 



\<- 



■i. 



). 



* -a 




k - 

f 

ft 


4 


.. K. 


^ 1 



i 'per 



1 - 



■^^^ tii( 



e 



■^ 
^ 



f 
I 



1 



'■^- i^j ^, 



7 



1 1 

5 



r r 



V 



1 



VJ*- 



i.-A^L^ -^ 



.« 

I. 



1'-. 



tbe ' 

I 

obi ^ ; 

's * Sur- 



Sect. III.] 



HYDROGRAPHY 



71 



be the correctness of the result. It is clear that the 
true bearing of the object at each station should b 






served (see Astronomical Bearing) ; that the course steered 
should, if possible, be equally well known ; (this is eiFected 
in the best manner by observing the magnetic bearing of 
the object with the compass which directs the base, or 
that which is to be steered by in-running the base ; at 



«r" 



ar - 



»t6r. 



the same time that its true hearing is observed ;) that the 
distance run should be determined by patent log ; that the 
ship should be on her course at starting when the bearings 
are observed; and that the log should be put over and 
hauled in at the instant of making the obseryations. If 
the ship should of necessity alter her course during the 
operation, it should be carefully noted, the log looked at, 
and fresh bearings of the objects taken. 

Tvv^o observers are necessary to accomplish these ob- 
servations nicely, and without hurry. 

AVith these data the height of the object may be found 
with considerable accuracy,* e^-p^cially if the dip-sector be 
used. Having determined the height of a mountain, you 
may often find it useful to know your distance from it 
Avlien cruising oif the coast ; and it will also aiTord amuse- 



tf - 



f. 



ment and practice to see how near you can fix the ship 
by it, as compared with cross-bearings or other observa- 
tions. For this purpose it will be convenient to make a 
constant for the height, t 



^ .ill 



-; 



'\'^' 



.'.0 



Lighthouses. 

14. If lighthouses are erected upon xho coast, dczcribe 
exactly their locality, geographical position, appearii._j, 




* See Appendix No, 2. 



f See x\ppendix No. 








»»-f 



- -i 



« .F 




2 



HYDROGRAPHY. 



[Sect. III. 



height of the lantern 



the tower, whether the light he fixed or revolving, inter- 
mittent, coloured, or otherwise ; the distance which it 
may be seen, and the bearings on which the light is 
visible. If the light be made use of for the purpose of 
avoiding any danger, state what the danger is, give its 



bearing from the lighthouse, and if the light be blinked or 



changed for this or any other purpose, state what it is, and 
give the exact bearing on which the change takes place. 

If there be a lower light in the tower for this, or any 
purpose of tide work, state as before the bearing on 
which it opens and obscures, or the times of tide when it 
is exhibited and extinguished, and how many feet it is 
below the upper light. State wliether pilots are required 
for the port, and where they are likely to be met with, 



of 




In Port. 



15. \Vhen at anchor, give the depth of the water, nature 



of the orround, an 




d whether any precautions are neces- 



W JL 



sary, with respect to protecting the cables if hempen, and 
whether it be proper to moor in consequence of the diffi- 
culty of keeping a clear anchor, or from the treacherous 
holding or sloping of the ground. Fix the spot by cross- 
bearings of conspicuous and well-known objects, and note 
the direction and rate of the tide, and the duration of 
both ebb and fxood stream. 



16. The geographical position of a port will necessarily 

3Upy the attention of thft nprsntiQ in wh<,«fi hands 




of the persons in whose hand 
remarks may be placed, and by assiduity much 
may be done in a short time with a sextant and artificial 



■rl.l 



^^^■ 



/>ni v» 



r : 



i^ 



;<u 



i lA' 



^ 



„ .Vro" 



V- 



. will (ot 



I.'^p 






t 






V 

t 



y; ' 



4 



I *-' 



r! -' 'J 

rest BeSi-J" 
for ratiDg tr- 



17. A snrvi 
. have 






- ^ 



-•iW: 



-' .vHl 



'1 H V, 



p.'^ . 1 

^^* M.0, 



l- fi 



Iti 



IS 



'••'' ^'anner 



^t in^ 



V 



II 



nf 



* • 



-.1 



of 
• tl 
1 



''^ of 1- . 



^> 



^ ■* 



M'. 1 






t^n- 



'U 



:. I • , 



*0 wl t 



■'it 



I 



yi 



■ ;> 



J? 



'"^^^'•^^ka^r 



^ I t 



X 



w 



r 



ii 



\ f\r^ <-.. 



c ■ 



Sect. III.] 



HYDROGRAPHY. 



73 



horizon only. But if to these be added a transit and a 
good achromatic telescope, the longitude by occulta tiers, 
raoon-culminating stars, and eclipses of Jupiter's satel- 
lites, will form a valuabb addition to that by observa- 
tions of lunar distances with the sextant. 

The earliest opportunity should be taken of determin- 
ing the error of the ehronoraetere upon mean time at the 

and evening sights, or by equal alti- 



momm 




tudes, which is better. Chronomete 



,^*Q 



will 



;oii 






change their rates on the transition from a passage in 
which they have been constantly in motion to a state of 
rest. Besides which, early sights afford a longer interval 
for ratiner the watches again. 




f 



1-*- - , i ^U ^t*i i-U 



^.. 1 



' i>eni 



m^ 




;fhor- 



f ii^ ^ 



\ Li- 



_^ 



I " 



I 



iJ 



1 



,-■''■ 



i 



. J 1^ 



^J 



V 



1., 



^ V 



. 1 



:ii^ 



/^ ■ 



1^' 



J 



\i. 



n 



. ,::d^" 



-/ 



Survey of a Port 

17. A survey of the port and description of the anchor- 
age will always be desirable if carefully made. If former 
surveys have been executed, it will afford a useful com- 
parison, and detect alterations of the banks and channels, 
and the silting up of the port if any. If they have not, 
such a survey will be doubly useful, and the industrious 
observer will find very few plans of ports to which he 
may not usefully add a few soundings or explanatory 
remarks. 

It is not intended in this manual to enter much into 
the manner of executing a survey, as there are several 
treatises on the subject, which contain the necessary 
information ; but these works may possibly not be on 
board, and as " golden opportunities '' of acquiring a 
knowledge of distant ports may thus be lost, from the 
want of knowing how to construct a rough survey of a 

E 



74 



HYP ^ '^ G R APHY 



[Sect. III. 



1 



Sect 



III 



place, by persons who probably never contemplated the 
performance of such an undertaking, it may be usefiil 
to describe as briefly as possible the process. Make 
choice of two stations at as great a distance apart as 
the survey will admit of, and from which the eye can see 
over a considerable portion of the ground to be mapped 
as A, B, plate A. Put up marks or select objects 
at all convenient places around the survey, so as to be 
able to form a network of triangles over the whole space 
and include every conspicuous feature around, such as 
hills, cliffs, rocks, and especially objects at, or near, high- 



,.'n€ 



water maric„ 



Jtlavin 



D 



upon these marks, as at A 



? 



c 



■shore if there be a convenient spot at hand ; but it would 
be Useless to devote much time to this purpose, for the 
survey of a port in general does not so much require that 
the absolute distances between places should be accurately 
known, as that the angles should he carefully observed, 
and therefore the relative distances preserved. If it be 

X 

hecessary to measure a short base of a quarter or half a 
mile, and the ground be uneven, plant staves (boarding- 
pikes) in the line to be measured, and stretch the lead 
line along from pike to pike in the direction of the wire 
of the thoodolite v/hen levelled; and inpasure along the 
line with a tape, or with rods ; then shift the pikes and 
ine on, until the rL.niired distance has been measured, 
the length of which should not be less than l-7th of the 

distance between the objects, the distance of which is re- 
quired. 

If a micrometer be on board, a very fair base may be 



I 



\ 

\ 

r 



obi*"' 



the 



afl 



fro ^6 



as 



\ 



riffht a 

the ^ 
distanc 

betwee 
If neit 



operau 

la 



1 * 



^wv^>^ 



ID mo, 



If 



v. ~ 



the b€ 

quart, 
the ("■ 

begin 

the cv. 



^'ouot 



r ^ 



W ' 



\-^- 



ii 



See 
"^f this i 

tTh, 



\ 



h,i[ 



\ 



f> 



ii, 



.:'! 



4r - 



span 



t V 



TV* 



fn' 



I.. 



! 



lAn 



r.b 



^i 



;A,B,r 



:r::.] nr^ 



iJt 



^ » 



,, m 






T 



yv 1A' 



/ 



Ifu^ 



i^r 



hali'- 



V-r, 






oft 



^u ^ire 






-V^( 



e (-iii? 



Sect. III.] 



HYDEOGRAPHY 



75 




obtcdned with it,* or even with a sextant, by rneasurin 
the angle subtended by a staff placed at right angles to 
the observer, and the distance carefully measured between 
two well-defined marks, one at either end of the staff (such 
as the clean edore of a sheet of white paper wrapped round 




each end) : the best way of ensuring the staff being 
right angles nearly, is to place it upright by a plumb' 
line. Then treating the figure as a right-angled ti-iangle 



and the base the 



the staff will be the perpendicular, 
distance between your eye and the station, which may be 
readily computed, as all the angles and a side are 
known ; but if a micrometer be used, the distance is that 
between the staff and the ohjeet-glass of the telescope- 
If neither of these methods be adopted, or if the field of 
operations be very extensive, a base by sound, though 

r 

much less accurate, may be found convenient. 

19. The measurement of a base by sound, if several 
trials are made, and the distance be more than a mile, will, 
in most cases, be sufficiently exact for the above purposes. 
If possible land a swivel or small gun upon one of your 



stations, and go yourself to the other, the more distant 



the better. Appoint a signal to be shown half or a 
quarter of a minute before each explosion, in order that 
the eye may rest between. When the signal is made 
begin to note the beats,! but not to count until you see 
the explosion, and then let the next beat be one^ and so 



s be 



done 



count up until you hear the report. Let thi 

several times, and at the end mean the beats, and turn 



filS 



\^t^' 



l.fS 






* See the Book of Tables and Directions supplied with an instrument 
of this kind, by Rochon. 

f The stop-watch by Mr. Dent is very convenient for this purpose. 

E 2 



76 



HYDROGRAPHY. 



[Sect. Ill, 



them into seconds of time by the number of strokes your 
watch makes in a minute* Then, by multiplying this 
number of seconds by 1090, and adding one foot for every 
two degrees of the thermometer above freezing-point^ you 
will obtain the length of the base in feet. 

To give a direction to the base, the readiest way is to 
observe the passage of the sun's limbs over the wires of 
the theodolite nicely levelled, and to note the time by a 
watch, or to take corresponding altitudes, in order to com- 
pute the azimuth. If you have only a sextant, astrono- 
mical bearing will be found convenient and sufficiently 




correct, provided the horizon can be seen at a sufficient 

. By either of these methods the angle between 
the base and the limb of the sun will be known, and 
hence the true bearing of the object obtained; or if 
the magnetic bearing of the object be observed by an 
azimuth compass, and the variation be determined at the 
same time, it wdll still be known near enough for the 
common purposes of navigation. Having arranged the 



gtb of the base, at A and B 



? 



measure angles between the base and all the stations, 

les (if measured with a sextant) 




are as 



nearly 



a; 



possibh 



parallel 



with the horizon, 



ti 



and at all other convenient stations do the same. By 
his means the relative position of all the stations will 
be obtained, from any three of which the position of an- 
other, or of a boat for instance, may be determined by 



measuring 



two contiguous angles between them with 



a sextant. But whenever you have occasion to do this 
(and in sounding there is no more convenient method of 



fixing the place of the boat), be careful not to select sta- 



\ 






1 

\ 



( 



!> 



^ir 



V 



''^■■^ ^ 






will« 



A 



W 



r,u. 



'_/ 






e 



h 



20. 



t*>*- 



? 



r 



found I 

distanci 

other si 

Id a 



out '^ 



fi 



from c : 
if the ] 
11 






them 



a 



are to r 
intei . 



toth 



iei 



aadfix 
ation i 



a 



h 



'~0 ] 



line «- 

"^ the 
III 



ieof 



, ^- 



N 



0-4. 



u. 



^» 



"? 



n 



^' 



.'// 



Ut • , 



*w 



I-.'. 






t 



rt 1 



J\. 



i-\ 



5 



; or ii 

bv f^.-O 



I at 



f^ 



.1.^ 



1 ■ 



ruvt 



. -t^^ 



ir, 



re. By 



lO 



f 



it** 



r 



.J. 



UU 



J 



f 



,f aa- 



Sect. III.] 



HYDROGRAPHY 



77 



tions which lie in a curve concave towai^ds yon^ since cases 
will often arise when stations m situated will give very 
inaccurate results, as with the 

plate A, 

20. While operations on shore are going forward, boat 



objects A H I at p in 



can be sounding out the harbour, and fixing the points of 
reefs, rocks, &C.5 bearing in mind that it will always be 
found more satisfactory to land upon every rock or point, 
&c,, than to lie off in the boat, and fix them by estimated 
distances or by intersections, either from these or from 

other stations. 

In sounding, fix the boat at starting by two sextant 
angles ; note the direction in which it is intended to run 
out the line of soundings, and note any two objects distant 
fi:*om each other, that are in a line upon that bearing, or 



if the port be not too extensive make use of staves with 



flag 



"^ 



shifting them along the coast at the end of each line 



of soundings the exact distance it is intended to run 
them apart — the boat showing a signal when the flags 

sound at regular 




are to move ; then keep the marks on, and ; 
intervals 6, 5, 4, 3, 2, or fewer casts in a minute accordin 
to the depth ; and at given short intervals note the time 
and fix the position of the boat by two angles as before- 
mentioned,* as also whenever there is any material alter- 
ation in the depth, or whenever the number of casts 



alters in a given time. When 



line fix the boat's position, and alter the course, sounding 
all the time until far enough for running back the second 



line of soundings parallel with the first. Fix the boat's 

* See the form in Appendix for entering these angles and soundings^ 
No. 4. 



7 




HYDROGRAPHY. 



[Sect, iir. 



station here again, and take a new leading mark. If 
tlie eye cannot catch a leading object at the moment 
drop the grapnel to maintain the spot, for much more 
time is lost by over-running the lines than by coolly 
waiting for a guide to direct the course. Proceed in this 



manner, running all the soundings in parallel lines or 



nearly so, until the anchorage is all sounded out. 

Having mapped all that is intended to be comprised in 
the survey, protract the work carefully on board upon a 
sheet of drawing paper. Draw in the coast hne, rocks. 



shoa 



s, hills, &c., and every other feature from your 
rough, attending to the hydrographic method of delinea- 
tion represented in plate A. 

21. The soundings follow next, when reduced to the low 
water standard of the port by the tide gauge.* If there 
be no station-pointer on board, protract the angles upon 
a piece of transparent paper, and mark the stations with 
their proper numburs. If the soundings have been taken 



equally, divide the spaces between the A 's in as many 
parts as there are casts, and fill in the corrected sound- 
ings in the order in which they occur. All soundings 
which may have been taken when the tide was up and 
by reduction to low water are dry : draw a line under. 
very chart-box in the service will be found the abbre- 



I 



n e 



Ch 



No 



viations adopted in Admiralty 

strictly followed, and in Appen 

symbols which will be found useful in taking angles, &c., 

and in other surveying operations ; and in plate A are 

given the usual hydrographic delineations of banks, cliffs, 
shoals, &c. 

* See Art. 24. 



* 
f 



* 






1 



L 



y 






. iii-i 



i/^' 



l;^^T 



eft 



f^ 



>' 



iC 



7-// 

tie 



rei^ 



by 



the 



lieig 



ishts*^ 



cu 



If tli 

ted, 



s 



ur^ey, <: 
a few SOI 

Rocbon 



21 A 



$ 



^'^^' i 1 



; 



The 



Art. 11 

and w ' 
•' «. dthr ■ 



one 



J 






1 



and ^ii 



■^*.^ 



^ater i 
calcu] 



a 



^*oard. 



«^. ]^ 



>* 



'I . 



^v 



i 



1 

V 



. l^i fV\ 




*44 






JSU 



1 '• 



n \ 



f 



i 



^' 



1 



i 



• 1 ■, 



i^ 



-". T 



i'..,- 



,t' 



K 



^ 



Sect. III.] 



HYDROGRAPHY. 



7kl 



Lastly, put a meridian line 



and scale to 



the plan. 



Iu.ert the variation, geographical position, time of H. W. 
F. and C, the low-water standard, to which the soundims 
are reduced, and the range at springs and at neaps ; note 



the dui 
by the 




draw leading marks and put in views, 



mountains 



If time does not permit of a regular survey being exe- 
cuted, still a useful record may be made by an itinerant 
survey, or even an eye sketch, assisted by sextant angles, 
a few soundings judiciously taken, the true bearing of one 
object and the measurement of a base by sound, or with a 
Rochon micrometer as before-mentioned. 



Sailing Directions. 

22. Whenever a survey is executed, sailing directions 
should accompany it, and too much care carmot be be- 
stowed upon this important part of a surveyor's duty. 

They should contain a description of the coast (see 
Art. 11) ; directions for making the land ; for approach- 
ing, and sailing into or out of the port both by daylight 
and with the aid of marks, and also by night or in thick 



weather, when the lead and the lighthouse, if there be 

must be the seaman's principal guide. How 



one 



vessel is to proceed with a leading or a beating windj 
and with or against the tide—how far she may stand on 
either tack— what water she may expect to find at low- 
water springs— and how she may ascertain the depth by 
calculation on any other day — within what limits a vessel 
may safely steer in bad weather and when no pilot is on 
board— where the best anchorage lies, the depth in wliich 






^L 







^^ 



- ^^ 



80 



HYDROGRAPHY. 



[Sect. III. 



directions for bringing up. 

- have been mentioned under 

tlie heaas of approaching a port, especially noting all 



c 



beacons, buoys, lighthouses, and landmarks &o 
Art. 11). ' ^" 

Affix to these views of the land and sketches of the 
fading marks. The geographical position, the time of 
H. ^^ . F. and C, rise at springs and neaps, the low- 
water standard of the port, &c., and the variation of the 
compass, point out the best watering-places, and let all 
bearings given be magnetic, and noted as such. 




Illations 



placed at the end of these directions. 




Tide Pole. 
When a survey is determine 



2ft 



half an hour before to half 



should be registered every ten rmnutes.^ In addition to 



2f 



every half-hour to 



place of the water must be noted 
facilitate the reduction of the soundings to the k,7i^tl^ 
standard. The tide-gauge should be fixed in a well- 
sheltered spot, with its zero such a depth as to ensure its 
bemg below the low water at springs. When the pole is 
properly secured and settled down, paint a mark in the 
rocK corresponding with one of the divisions on the gauge, 
and note which in your book, in case the pole should be 
washed down. If you remain long enough in port, let 
your observations be continued at least through an entire 

* See Forms. Nos. ? and s. 



1 



i 



\ 



V 



M- 



* III-] 



l«nar 



mot 



!oW 



•,vater 



a 



ock 



level of I 

['.■ ■ ■ ■ 

by 



■^v 



r 



u 



:20ii: 



Let tb: 

Tlie bigh 
[M and 



mg 



r 



*iinf\ 



the 



sliould be 
with the { 

If tidr^ 

a Delt of I 

wlietlicr t 
strength, 
reefs and 



f 



aster th : 

la th 



e 



(No. 8) i 

other f Kc 
Forfu 



24. Br 

^^ethr 



tide 



3 



ee 



aud 



I 



%»• 






^ 



t\ 



\ V ^'' 



\^ 



^4 



le-1 '^ 



3 



n 



4:- 



_/ -.-' 



a 



V 



Sect, III.] 



HyDROGEAPHY 



81 



Imiar month. When you come away, mean the high and 



mean of them 



low water heights of each day^ and take a 



again for the mean -place of the water ^ and cut a mark in 



the rock corresponding with that mean level of the sea 
before you remove the pole. As this is the true scientific 

level of reference in all matters relative to the tides, 
ijfer this level again to some mark in a contiguous 



building, that a reference may at any time be made to it, 
by persons who might not be able to find the rock. 

Let the w^atch be always at mean time at the place. 



Tlie hi^h and low water observations should be continued 







night and day with equal carefulness in order to deter- 
mine the amount of diurnal tide ; and every observation 
should be recorded, although it mav not seem to agree 

with the others. 



1^ ■ 



r _- 



If tides are taken 



^^ 



t coral islands, or a 



t stations within 



a belt of coral, it should alw^ays be noted in tlio journal 
whether the sea or land breeze be blowing and with what 
strength, and also whether the surf be h^gh upon the 



-^ 



reefs and sending its water into the lagoon, fillin 




it 



faster than it can escape. 

In the Appendix will be found two forms, one cf which 



(No, 8) is for registering the tides every half hour, th 






other (No. 7) is for the high and low water only. 

For further information upon the tides see that section. 



-rfi-^ 






r 



1 i. 



'^,1 



giifc. 



Soundings. 

24. Before any soundings are inserted in the chart they 
should be reduced to a standard obtained by meanin 
the three or four successive lowest waters of c:ich spring- 
tide, and meaning them again for a general mean. Tliis 




e3 



82 



HYDROGRAPHY. 



[Sect. III. 



st?"dard should be noted in a very conspicuous and un-- 
mistakcable manner as being so many feet below the 
mean water level, and recorded as the low water standard 
of the port. It is a quantity which would nearly corre- 
spond with half the range of an ordinary spring tide, 
a term often written without any direct reference to the 
low water standard, and so ambiguous that it is to be 
hoped it will soon disappear from the face of our charts. 
With this standard, and the known daily height of the 
tide above mean water level, soundings taken at anv 
hour may be prepared for comparison with the depths 
upon the chart by the simple formula 



E 



T r 



. ft 
cosine I— , 



180 






Zir 



= the lot^^ water standard to which the chart is adapted. 
= the height of tide for the day aboT8 mean water leyel. 
= the duration of the tide. 
— the time from high water previous. 

Or, enter the traverse table with the time from the 
nearest high water as a course (allowing 5^ of arc to 



Where R 

r 

D 

t 



time) 



(half the range 



of tide for the day) as a distance ; in the latitude column 
will stand a quantity which applied to the loio water 



of 



according as the arc is less 



or greaier than 90% will give the reduction required. 



V - 



If the arc exceeds 90*^ take its supplement. But it is to 
be observed that all these corrections, although pre- 
ferable to the old method of reducing soundings, are but 
approximations. In many places, especially in such as 
have great tides, it is nocessarv to distinimish betweea 



rising ^adfall 
If in a conn' 



e 



arthquakes, carefully watci 



i 






) 



s 



^^^ 



lit] 



the ti^^'^ 



lOfl 



Be^^' 




A-* 



of a 



rivei 



a 



har 



> 



<f' 



tion 



of 



25. H 




■u^-- 



1 



rolling 
and rusl 
even to 



u 



^m- ^ 



FT-* 



.1-Jj 



height ♦ ■ 
resi'ect 1 



.*. 



n 



below t] 

tides; : 
correct.^ 



26, ( 

periodic 



occa="-. 



the 
level 



r 



coiii 



Oj 



'I tile be 



^ 



i 



L 



Y% 



Sect. III.] 



HYDROGRAPHY. 



8 




>-» 



tf 



V 



t 



'* 



V* '.R* 



«♦ 



. f 



1 1 




^ f^ 



rC 



■t"-'^' 



, 1 



re 



f . 






i 



^'' 



.11 



the tide-pole during and after the 'shock, and if any un 



U. Xi 



dulations of the water are observed, note them, and the 



they pr( 
'^er to pi 







h 



guard 



$- 



a bar, sand-bank, or any such impediment to the free 



action of the water. 



The Bore 



nomenon, the bore, a wave w^hich 



place 



ph 



he 



? 



threatening destruction to boats and 



even to shipping ; note the time of the tide at which it 



and rushing onward 



begins, 



there be one tmve only or more, the 



fbTSt 



with 
and 



and 



below the spot- The 



tides ; note 
correct.* 



cularly whether this observation be 



Freshes. 



26, Connected with the rise and fall of the water is that 
periodical elevation of the surface of rivers by "freshes,'* 
occasioned by heavy and continued rains in the interior of 



the countrv- 



.nly 



here 



level of the river ^ properly so called ; but " 

♦ The reraark made in '' How to observe [p. 35] that either rocks or 
shoals, or great depth of water secure a river from the inconvenience 
of the bore," is not always correct; for the Severn is encumbered with 
shoals, and has a bore which has proved destructive to vessels grounded 
upon ^he sands. 



r 



^ 

i 



J 



\ 









84 



HYDROGRAPHY. 



[Sect. lit. 



exists, also raise the level there, so that vcbsek which 
cannot enter during the dry season are at such times ' ^ - 



to pass over the bar. 



biiri 



,s 



to rise, when it attains its maximum, when it begins to 
subside and regains its mean or ordinary level, should be 
carefully noted, and with it the elevation of the water in 
feet, both in its ascent and descent. 



Discovery of Land. 



On 






the first endeavonFj after the vessel is placed in safety, 



bllOil 



as 



as 



the means of observation admit, and not to quit the 
spot until the danger is satisfactorily placed upon the 
chart.* Describe it as accurately as you can ; detei^.ine 
its extent, height, and configuration ; the adjacent sound- 
ings, and the quality of the ground ; and give a sketch 
of its outline. If it be extensive, a running survey will 



t If it be 



within sig 



5 



it 



* 



.^ 



position must be fixed by bearings or angles between 
known points of the coast, and some conspicuous objects 
upon the land selected, which being hronght in a line 
will lead ships clear of the danger. Do this for t^^^h 
sides, and give correct bearings of the transits, and, if 
possible, sketches of the objects. 

F 

* See Raper's ^ Navigation/ 855, d. 328; and 856, p. 329. *'No com- 
mander of a vessel/' observes that talented oflScer, " who might meet 
miexpectedly any danger (before unknown), could be excused, except by 
urgent circumstances, from taking the necessary steps both for ascer- 



taiuing Its true position and for giving a description as complete as a pru- 
dent regard to his own safety aUowed/' 
t See Ait. 29, 




m 



1 







( 



I 






f i 




i 



I, 
II 



^i !i 




X 



X 



1 



\ * 



k. 



«i 



II 



\ 



4 

T 





j:&i:.Waikf^< f>cu^5 



tf*-- 




k 



. % 



-I 



^ 

m 
m 





i 



( 




V ^ 







■A^; v';.-> 





! 











^J*_--^ 



«i' v»".S 






^v/^-" 



iJ ■ TO. 





n 



*ll 






) 



^^^- 



Sect. III.] 



HYDROGRAPHY. 



85 



A 



S 



1 
^ 



} 

t 

I 

J 

w 



t 

* 



regards coasts, and islands which are bnt little 



known, T hw.e given in the Appendix a list of such as are 




most deserving of attention, extracted from a retmn made 
by the able and indefatigable officer at the head of the 
Hydrograpliic department to an order of the House of 
Commons, 1848, and all general directions for acquiring 
information which may have been already given must be 
considered to apply with double force to these countries. 
The limits of this paper do not permit of our cnterin 
into particulars as to the probable position of places wliich 
may be imperfectly determined, nor of the reported posi- 
tion of islands wliich are considered doubtful. In the 
Atlantic alone, for instance, there are islands reported 
continually where none could possibly exist ; and the 
islands of the Pacific have been multiplied by the errors 
of the longitudes of persons visiting them; but wherever 
the charts place any islands as doubtful, which you wish 
+^> seek (as it is always more probable that the latitude is 
correct than the longitude), the parallel of the supposed 
latitude should be gained, at a meridian sufficiently dis- 



tant from that given to exceed the probable limit of error 
in longitude, and a due east or v/est course pursued until a 
similarly distant meridian is gained on the other side ; and 
if there should be any change in the colour of the water, 
sounding ought by all means to be tried ; and especially 

the 



we call attention to soundings upon the site near 
equator marked as the seat of volcanic action from about 
Si S. and irf to 24^ W., and also to the vicinity of the 
great bank S. and S.E. from the Falkland Islands, called 
Burdwood Bank, on which there has been found recently 



as little as 24 fathoms ; the A^ulhas Bank, and the 






86 



HyUROGKAPHY. 



[Sect III. 



sites of any volcanic islands wliich may have risen and 
disappeared-"^ 

Bailing along a Coast. 
28. When sailing along a coast or islands which may 



even be known and charted, it is advisable, as a general 



practi 






r^ 




coast 



"^ 



as the ship sails alon 
indifferently explored, no opportunity should be omitted 
of determining as accurately as possible the position of 
every part within your power* 

The position of places is determined: from a ship with 
the least disadvantage, by being brought to bear east or 
w^est when the latitude is taken, and north or south when 
longitude is observed. And as these observations may 
be made during several hours of the day,! much may be 



done in a snigle day's run, especially if patent log bases 



connect the stations, and astronomical bearings be em 



ployed. And upon all occasions the noting of transits, 
or the coming in a line of remarkable objects and of 
points of interest, should form a necessary portion of 



our duty, although we may believe them to be already 



satisfactorily determined, as they afford the most critical 
test of the accuracy of former surveys, and are especially 



useful in cases where longitudes of contiguous places 
may have been had by different observers. 

If time admits of more than this being done, and in 
some of the countries which are but little explored, it is 



* Set rlso Art. 4, 

t See Rapers Navigation, 830 et eeq., p. 320 j also 834, p< ^^i? 
second edition. 



r 



\ 




\ 



Sect' 



extr- 
perf' 

out 
and 

and 
ma} 



2 

disti 

the 

(Ar 

the 
obsc 

weij 

C0U1 

adir 
the 

and 
as { 

heai 
pate 

othe 
hers 

the 
neec 

be; 

take 
thej 





i::^i^-i^-^ 



Wp V- 



T 
i 



I 



bi 



k 4 



■'^ 



L«* 



h. ^ 



M .-, 



iC 



v.. 



I 




r, 



'^IDu 



* • 



htio^ 




K 



or* 



^ 



^ t- 



<1IW. 



IV 



r 



F 



}v 



ii.9 



V* 







. 1 



> ^y- 



dT 



H ar 



.:^ 



«' 



rOh^o 



'> 



^f... 



rf 



• exp 






4iPi 



jl**' 



u 



Sect. III.] 



HYDROGRAPHY. 



87 



extremely desirable that no opportunity sliould be lost of 
perfecting their outline, the heavy boat? may be hoisted 
out and sent in shore of the ship to run in the coast line 
and the detail whilst the ship carries on a triangulation 
and continuation of bases in the distance, making what 
may be termed a running survey. 



Running Survey 



Whenever 



distance of 4, 5, or 6 miles at starting, and let them and 
the ship anchor, if possible, to measure a base by sound 




to 



(Art. 19), and to get astronomical bearmgs and ar 
the same points. Fix the ship's position by repeated 
observations for the latitude and by chronometer ; then 
weigh and put the patent log over and steer a steady 



course alon 




( 



admit of it, without stopping). One boat now runs along 
the land from point to point, putting in the coast line 
and its detail, getting astronomical bearings and angles 
as she proceeds, especially of all transits of points and 
headlands, and measuring her distance between them by 
patent log, and sounding, but without stoppinsr. The 




other boat attends principally to the soundings, fixing 
herself as she requires, by angles and bearings between 
the points determined by the other "boat and the ship. 

At the end of a few miles' run, or at noon, or when 
necessary to renew the angles and bearings, a signal is to 
be shown and the logs are then to be hauled in and 
read off, but not reset, fresh angles and bearings to be 
taken and a new base commenced, the distance between 
the ship and boats being again measured by sound. The 



88 



HYDnOGRAPHY. 



[Sect III. 



Sect. I 



log IS then again put o^ er and the course of the vessel 
resumed. In this manner the day passes, the hearinfrs 
and observations all being worked out at the moment 
the outline run in, views taken, and every particular 

r 

mapped and booked at the time so as to leave nothing 
to memory. At the close of the day's operations anchor 

sound, and repeat 



n nosition, measure a 



base 




operations as at starting, recall the boats, and in the 
grey of evening get tlie ship's position by stars and 
planets, v^hich may at this time be observed with great 
accuracy before the horizon becomes too obscure. If the 
ship can remain at anchor, she will observe the set of the 
stream and the rise and fall of the water, however roughly 
it may be done. 

As early as possible commit the triangulation to paper 
that the vessel may start in the morning with some points 
of land well fixed so as to enable the ship to continue her 



triangulation throughout the day without the aid of the 



boat— although her co-operation as before should be 
renewed. 

If there be no anchorage, the ship will maintain her 
position during the night under canvas, and in the grey of 
the morning picking up the place where she left off on the 
preceding evening, send the boats away, get altitudes of 
stars for latitude and longitude, measure a base by sound ; 
get astronomical bearings and angles, &C.5 and putting 
over the patent logs continue along the coast as before. 



* 



Thus far we have considered the 



observations as being 
wholly coniiued to the vessels, but it will add considerably 

For farther informatioa, and a more extensive application of this 
methed, see Belcher, Mackenzie, and other works on nautical surveying. 



\ 

r 



} 



t 







I 



J 



to 



adt 



noiiii 
ndl 



a 



3C 
charl 
adva 
line J 
set 
on Vf 
to th( 
and I 
yout 

and 

No.; 

of CO 

when 
10 d. 
offb 
are t 
throu 
meric 



usei 



ii 



to the 

tract! 
latitu 

ahsoh 

^eces! 

Proce, 
some 



i 






Sect. III.] 



HYDROGRAPHlt. 



89 



*.' h 



^*ui 



,- 1 



!»• 







It- 




m< 



*\\v 



■ J. 



t t 



It I 



1 



u 



I in 



lA" 






1 






i- 






b n 









^i 



t 






\^ 



i. vj 



to the accuracy of the survey if landings be occasionally 
made, and the stations be critically determined by astro- 
nomical observation, i. e., by latitudes and chronomete 
and the positions connected with the rest of the \^ork. 

30. It is not necessary to be provided with a regular 
chart for this purpose ; the projection may proceed as you 
advance. Thus, consider how the coast runs, and draw a 



line along the paper to represent the meridian at starting ; 
set off on this a degree of latitude according to the scale 
on Avhich the survev is to nroceed, 1 inch or IJ inchpB 
to the mile, or more or less according to circurastanceSj 



and begin at once to lay off the bearings and angles. K% 




you take up other stations proceed to throw out meridians 
and parallels in the manner described in 
No. 10. A chart upon this projection will be found easy 
of construction and more satisfactory than any other ; and 



\7k 



when the survey does not extend over more than 8 or 
10 degrees of latitude is sufficiently correct. In laying 
off bearhigs upon it, it must be borne in mind that they 
are to be projected with reference to the meridian passing 
through the spot. Mercator's projection, in which the 
meridians are all parallel, and which is in such general 
use in the navy, except in very low latitudes, is not adapted 
to the purposes of a survey, as the bearings and the pro- 
traction will never agree together nor with the observed 

latitude and longitude of the stations. 

With reference to the longitude I may remark, that the 
absolute longitude of the place is not required, but it is 
necessary to determine the difference of meridians as you 

h 

proceed ; and these should afterwards be compared with 
some well-determined meridian. I may observe here, 






90 



HyBEOGBAPIiy. 



[Sect. III. 



once for all, that the longitude of a place, by chronome- 
ter, from Greenwich^ should never be given without the 
accompanying longitude from which the deduction of the 

made ; in short, that clironometers should 



meridian was 



be referred to only as a measure ^^f differences. 



Coral Islands. 

31. Should coral islands be fallen in with, determine 
their position, extent, and map their outline; fix the 



openings into the lagoons, and describe their general 
appearance, whether wooded or not, and whether any 
high clumps of trees (distinguishing the palms) he con- 
spicuous upon them, and at what part ; you should then 
particularly notice the slope of the coral on both the 
outside of the island and the inside, and run off hues of 



soundings in various 



great a depth as you can reach, and at each cast par- 
ticularly note the bottom, whether it be living or dead 

depth at which live coral is 



coral 



note the 




brought up : the existence of livin 



1 



a point of interest* A 



coral at great depths 
fixed to the lead will 




often bring up specimens of coral which might otherwise 
be missed. 

Point out the place of the anchorage in the lagoon by an 
anchor, and state whether vessels can sail in with the trade 
wind or not, and the best time for going in, for in niaiiy 
of these Islands there is so strono: a current running out 



through the channel after the trade wind has set m, in 

the morning, as to render it imprudent to attempt the 

pas 

sides, and the land breeze has commenced, that the P^^ 






and in some it is only after the sea wind su^ 



ft 



\ 



r 



Sect. 



1 



breez 
occas 

into 

obse' 

chan: 

sidei 
spots 
upon 

Ci 

alltl: 

and 

mark 



32 

point 

pract 

point 
we s 

are t 

the 

rangf 

aido 

tiguo 
featu: 

whicl 



\ 



our 



to 
of 



F 



ai 



ping, 
may, 



Sect. TIL] 



HYDKOGRAPHY 



91 



"liU 




^nn*. 



« * 



-fis 



\ * 



yt 



1^ 



• • 



Md ni 



f>. 



1 



:yo\i 



co:.' on 



■d t 



iiH 



. V. 



hich 



16 



r4a* 



1 f 









1. 



r 




ID 



t 



foi 



.the 



i^t 



V' 



flPected. It is 




up With the 



sage can be ettectecl. It is the sea getbi 

breeze and beating over the reefs into the lagoon that 



occasions such a current 



through the 



openm 




Inquire 






into this on the spot, and do not commence any tide 
observations in the lagoon if the reefs are low and 
channel small : if, however, the lagoon be open on one 
side and sheltered on the side of the prevailing wind, these 
spots in the ocean afford excellent places for observations 

upon the tides. 

Currents occasioned by the trade-wind prevail about 
all the islands situated in those latitudes ; their direction 
and force should be ascertained and stated in your re- 
marks. 

Riversi. 

32. All rivers should be traced to the furthest possible 
point that time will allow, for although it is the usual 
practice to limit hydrographic inquiry to the vanishing 
noint'Of tidal influence, yet there are many reasons why 



X 



we should not here so circumscribe our views. Rivers 
are the great arterial features of our globe ; they define 



the valleys, give boundaries to the hills and mountain 
ranges, and if traced to their source enable us, with the 
aid of a few well-determined culminating points of con- 



tiguous ranges, to trace upon our charts the general 



feature of the country through which they flow. Besides 
which they arc so far connected with the navigation of 
our ports and harbours that their aid is often indispensable 
to a free access and egress, by affording a powerful means 



of scouring channels and removing impediments to ship- 
ping, which would otherwise be denied admission* They 
may therefore be said to be of almost equal importance 



92 



HYBROGRAPHY. 



[Sect. Ill 



g^rt 



III 



hvdrography as to pliysical geograpby 



In all 



cases 



then where rivers approach or flow into any of the ports 

examination, you should acquire as extensive a 



under 



knowledge of them as you possibly can, map as much of 
the windings and feature as is practicable, and especially 
of such parts of those that are not navigable as may be 
made available to the improvement of the navigation of 
the port, or in any way be converted to hydrographic use 
particularly noting the depth, extent, and variations of 



surface, of 



all widenings of the stream, or basins ajQTordinw 



back water and capable of being retained 



to a scouring power, carefully determinuig the elevation 
of the surface above the meaji level of the ocean, and, if the 
river does not run into the port, whether it could not 
be conveyed to it, and with what facihty. These inland 
basLis are occasionally greatly affected by mountain tor- 
rents, melting of snow, and rainy periods, raising their 
surface to an extraordinary height even in a few days ; 
while, on the other hand, long dry seasons depress them as 
much below the mean level. Our endeavour should be 



measu 



to ascertain these variations and the mean level of the 
water of the basin ; we may often see, for weeks after 
the event, the mark of the wash of the water around the 
lake or basin far above the existing level ; this may be 

red and compared with the place of the mean 
level, and be coupled with the place of the water accord- 
ing to the best information to be procured at the place 
(noting the informant). 

Note the depth and capability of transport or of inland 
navigation, and the power of traversing the stream for 
military purposes | also the nature and pecuharity of 



f 

r 



I 



CO 



nstrt 



re ( 



hav 
tance ' 

sels, "Q 
In 

facilit; 

bar, ii 
rocks, 

rate a 
and<>t 

runsn 
water 

the tid 
vation 

ocean. 
Las 

the ri(^ 
ward 



I 



stream 
It is bi 

which 
if a St 

necessi 
«very i 



33. 

^unnh: 






^ 



V- 



r- 



k ^ 



Sect III.] 



HYDROGRAPHY 



9" 



O 



I ^ V 



Tr^ 



^ 



it 






-,. 1 



P 



I 



bmI 



na 







m 



T 



1 



: - 



4* *v 




t 



leaT 



1 




*^ 



W 





J 



r 



V/> 




L 



i ii 



cure^' 



'ft 



i_" 



I 






'!■ 



construction of the vessels employed and the means they 
have of advancing against the stream, &c., and the dis- 



e 



tance to which navigation is practicable^ severally for ves- 
sels, boats, or barges. 

In large rivers communicating with the sea note the 
facihty of access and egress, the depth of water on the 
bar, if there be one,* the position and nature of shoals or 
rocks, and the navigable capabilities of the stream, th 
rate and duration of flood and ebb, that is, of the ingoing 
and outgoing stream. The distance to which the stream 
runs up, and the extent to which the rise and fall of the 
water is felt, or what may properly be called the end of 
the tide ; and here always, if possible, determine the ele- 
vation of the high-water line above the mean level of the 

ocean. 

Lastly, in speaking of rivers, let it be understood that 
the right or left bank should have reference to the do^vii- 
ward direction of its course, so that, when descending the 



stream, the right bank is on the right hand and rn.ce versa. 
It is better to adopt this phrase than to say east or west, 
which might at the least be ambiguous, for it is dear that 



if a stream meander much, its course being always of 



necessity downwards, it might be successively diverted to 
every point of the compass. 



Lakes, 



33. Lakes, properly so called, or which have no rivers 
running through them, can scarcely ever be turned to the 
uses of hydrography, except when they are upon a level 

* What has been already said on leading marks, lighthouses, beacons, 
buoys, &c., &c., of course applies here also. 






■_ ^ 



94 



HYDROGRAPHY. 



[Sect. III. 



with the sea, when a communication has been or may be 
made and a scouring power obtained by the admission of 
the tide through the port. However, what has been said 
of river basins may be applied to these enclosed sheets of 



water. The principal points are, their distance from the 
port, height above mean v/ater line of the ocean, depth. 






ensions, and fluctuation of surface, the quality, tem- 
perature, and sweetness of the water, the nature of the 



bed and borders^ inland navigation. 



if any^ &c. 



-r' 



Artificial Harbours. 

34. In all harbours, but especially in the vicinity of those 
which are formed by piers carried out into deep water, it 
is proper to notice whether tliere are shoals formed about 
the piers, and the pier-heads especially. If there are, 
obtain information as to the probable cause, when they 



Vr'ere first noticed, carefully note their extent and direc- 
tion, and connect with them the direction of the tide, ebb 
and flood, and if there be any stream through the piers 
out, or in, note its rate, direction, and the distance it ex- 
form and construction of artificial harbours, 



tends. 



rpi 



piers, and breakwaters, does not properly belong to hyJro- 




biit it may be well to describe and record 
the form of the breakwater, the pitch or slope of the 
stonework, the depth in which it is erected, the material 
of which it is composed, the nature of the work, and how 
it has resisted th. sea. Or if there be an opportunity of 
seeing it in a gale of wind, the power any peculiar form 



coaatruction of breakwater may have in repelling a 
heavy sea, or the eifect «ny peculiar form of pier may 
have in diverting the sea at the entrance from the 



0^^' 



till 



ancboi 



re 



•arc 



of th 



( 



nu 



ml? 



water 

manai 
effect- 
may! 

great 

possit 

been 

scare 



^1 



and at 



be 



35. 



vessels 

whethi 
vessels 
time, 

V towels 

or at 
ther 



e 



cranes 



he 



ac 



ciired 

yard, 



1. 



Sect. III.] 



HYDROGRAPnY 



95 



\ 



'^' 




OftM) 



1 1 



r ^ 



i 



t 



^ 







I 



'■■an- 



- of f. 



TO 



1 .. 



|pt^ 



4 



^K^ 







u' ■ ' 



fi.ni' 



I 



01 t 



anchorage within. 



T 




the entrance with 



regard to the offing stream and prevailing M-ind, the width 
of the channel, the protection of the anchorage, the 
numher of square acres enclosed. If there be any back- 
water, state its extent, how the scouring, if any, is 
managed, at what time of tide and what is its apparent 
efFect — and at all places wherever backwater is used, it 
mav be as well to sound off the mouth of the port to as 
great a distance as the effect of the scouring action can 
possibly extend— for occasionally injurious effects liave 
been produced by this powerful agent at a distance 
scarcely contemplated. State all deposits, siltings up, 
and at what rate it proceeds. 



Foreign Ports. 



35. In visiting foreign ports, a particular account should 
be given of the resources of the place in the event of 
vessels requiring either a repair or a refit. Such as 
whether there are any docks, wet or dry? what sized 
vessels they are capable of receiving, and how many at a 



time, is there a patent shp or gridiron, &c. 



How near 



vessels, of particular dimensions, can approach the wharfs, 
or at what time of tide lie alongside of them ; whether 
there are sheers for removing masts, and of what size, or 
cranes for lifting machinery and boilers ; whether there 
be a dockyard or arsenal, or whether stores can be pro- 
cured from other sources. Whether there is a steam- 
yard, and to what extent they cast and manufacture 



9 



machinery or boilers, or can repair steamers r 

Whether there is a coal depot, and what quantity of 



..ft^ 



^u 



HYDROGRAPHY. 



[Sect III. 



coal can be generally relied upon as at hand ; nature and 
quality of the material ? &c. 

Are there any piers, jetties^ or wharfs for landing pas- 
sengers, or cranes for carriages, and at what time of tide 
available ? If the country be low, are there any sea walls 
and would the country be flooded by their removal ? 



Waves. 



H 




6. Lastly, the attention of tlie observer should be 
directed to the measurement of the height, the extent 
and the velocity of the waves of the ocean. Not only of 
those high swelling seas which are common to every gale, 
but especially of those gigantic ridges which are occa- 



Cape 



rt 



Good 



and even in the Atlantic ; coming in couplets and triplets 
in the course of a gale, and occasioning fearful lurches 
which are long remembered. Opinions differ greatly as 
to the dimensions of these stupendous bodies, and any 
observations which will assist in determining their limits 
cannot fail to be acceptable. The inquiry is, fast, as to 
the height of the solid wave above the mean water level. 



Si 



Til 



rate at which the wave travels, and whether the height 
and distance of the ridges vary with the velocity. 
Fourthly, what is the greatest estimated extent of any 
one of those ridges. 

The most simple way of measuring the height, is, when 
the vessel is in the lowest part of the trough between two 
following seas, to ascend the rigging to such a height as 
will bring the top of the wave on with the horizon, to put 
a mark, note the inclination of the vessel, and at leisure 



gpct 



U 



to «i^' 

ijeicrhi 
neces= 

any ^' 
tance 

measi 

veerei 

the cr 
other, 

occupi 
the rai 
course 

There 
proble 
observ 
ample 

difficul 

obscrvi 





i 



Sect. III.] 



HYDROGRAPHY. 



96 a 




fPm 



rt^ ! 



\ 



■.fMt 



c r 



V 



U^. 



f 



• fl 



measure 



water line, which we may presume will be double the 
height of the wave above the mean water level. It will 
necessarily require several observations to be made before 
any satisfactory conclusion can be arrived at. The dis- 
tance of the waves apart may possibly be tested by actual 
measurement, by means of the lead-line and a float 
veered out to such a distance that the float shall be on 
the crest of one wave when the ship is on the top of the 
other. And the rate may be determined by the time 
occupied by the wave in passing from the float to the ship : 



the rate of the ship through the water and the angle her 
course makes with the route of the wave being known. 




There are other methods of determining this hiterestin 
problem which will no doubt occur to the intelligent 
observer, and they are sufficiently numerous to afford 
ample exercise of his ingenuity, but all are attended with 
difficulty owing to the circumstanc 



under which the 



made 



U H 



> 



gii' 



e4 




96 b 



M 





5h 






HYDROGRAPHY, 



CO 



f4 

H 

O 

< 






H 















^^ 






H 
S 






i p 



o i 

I 



^ 




o 



< \ w 

^■1 



f^^ 









O 



! 






^ 
Q 



p \^ 






3 



1^' 



ft 



o 



I 






[Sect. III. 






C! 2 « TJZ-^ 
■w O ^ .Z, CO 



0) 



g 



O^ 












Q 



^-^ 



2 k; 



J3 O '^ 



c 






o 






o 



CO 

4) 



•ad 



o 

Oi > 

c -^■ 






CO 









(^ 






sq-c 



4j 















Hr S hQ ^^ -C '2 



, c *^ -* 



go 



*1^ 






.«3 






<^\ 












as 
«i ^ ^ 

« qj ^ 



ei3 0) 

o "^ 



I M 



^ ^ t 
a) 



0,^ 



ceo 

o 

.1-1 ^ 

■4-J 2 



-— < 

CO 

o 

ei 
O 






S 






o 



eo A 



o 

Q.-M 






^ 00 OJ ^ 

. i^ si's e 






0) 






a; 



o 



T ?--rf 



-^ !« 2^ 



0,^ 



6> "^ 



&C 






5 " .:;: ^ -d -5 - 

n wi b! > * '^ 
o a; m ^ '^ o =J 






*^ e 71 ^ ' «- :b 






^„ c!j hH <; r- _ 



^^ 



1 

a 

m 






Of 



a. 






c6 



^ 

05 










S: gJ £.2^ -n^.>' -"'f^S^ 

O— • c8 U *- 






aj 






H 









^OT 



• ^ * _, t? C 



X 









gcc 






t- V Oft hn'r* « TO fC -M 









as 

C 

o 



6cr ^^ 

c C *^ V 

o S Si; 



ES Ij •♦.;> is 

4j ,>.'*» *- 



ipp^^' 



di-^-] 



f J .^»i th 



■^j 



it 



'X-i.- 



To 



taBgentofthis 
/ -eJ. the rest 

igle of 1^ 
.. 1.. 



■>ii* *"' 



r^a aired the 



i 



Dip . . 



ffofDip . 
Corre' ted Altitude 



T«,. 



!>'ieAl:...:e . 



^'".^.(^ 



Me( 



la 



8' 6 • 5424^ 



**l - 



^^g co< 



Sine 



? 






w 










'^Di 






'^S. 



'^'^^^ 



Appendix.] 



HYDROGRAPHY, 



•J' I 



APPENDIX No. 2. 



Tojind the Height of an Object the Distance ofivhich is known. 

Rule. — To the observed altitude apply the tnie dipj less the terrestrial 
refraetiou."* The result call corrected altitude ; to the log. of the diJ?- 
tance in yard?^ add the constant 8*073007, and find the log. of the sum^ 
which tarn into arc and add to the corrected altitude ; then to the log. 
tangent of this sum add the log, of the distance in yards as above-nien- 
tioned, the result will be the log. of the height of the object in yards. 

Example. — Mount Etna was seen at 57 miles distance, and subtended 
an angle of 1*^ 30' 00" with the horizon ; elevation of the eye 20 f(^eU 
required the height of the mountain ? 



Distance 57', i)i yKtds 115650 log 5 '063 157 

Constant . . , S "073^^07 



^ ■ 


Altitude ... f 30 
jDip ..." 4 


00 
43 

17 
26 
43 
48 


^ 


F- 


t! 

\xx of Dip , , H- 
Corrected Altitude 1 95 

+ 22 


w 

• • • 


- ^ 


True Altitude . . 1 48 


31 


Tangent , 
Constant 



60)1368" log=:3'l36154 



Correction , 22,48 

, 8-4993668 

, 5-0631570 

Yards. 

3*5625238 Ic^ 3652 heiijht required. 

X3 



V- 



% 



i- 



10956 feet. 



mm 



*■ r 



APPENDIX No. 3 



2> 



r 



To find the Constant for a Height, in order to compute its Dv^ance 

readily frojn its observed Altitude, 

Kui.E. — Froai the log. of the height in yards subtract the constant 
log. 6 • 5424481 , halve the sum — find its sine, and take out the correspond- 
ing co-sine, which is the constant required, (a) 



^-' 



• The terrestrial refraction variVs from | to xi P^^t of the arc. 

f If the Dip Sector had been used, the observed Dip should be substituted for these 
two quantities. 



98 



HYDROGRAPHY. 



[Sect III 



m 



To find the Distance. 

Rule.— From the observed altitude subtract the dip less the terrestrial 
refraction,* and call the remainder corrected altitude. To the constant 
above mentioned 6*5424481 add the cosine of the corrected altitude -dnA 
irom the cosine of the snm subtract the corrected altitude. The re- 
mainder is the log of the approximate distance in arc. Divide the 
approximate distance so found by the proportion of terrestrial refraction 
allowed, aid subtract the quotient from the before found corrected alti- 
tude for the true altitude. 

Lastly, add the cosine of the true altitude to the constant due to the 
height of the object (a) ; find the cosine of the sum, and subtract from it 
the true altitude ; the remainder is the distance in arc required. 

ExAMPT^. — Observed the altitude of Snowdon to be, On 45 
its height being 3565 feet = 1188 yards, 



00 
Off 45 10 



required its Constant and its Distance, height of eye 
being 14 feet. 

Log of height 3=0792499 
Constant. . 6'5424481 



45 5 mean. 



2)16'52980I8 



■T- 



Sine 



S'S;649009 



Cosine ™ 9^9999265 Constant required. 



To find the Distance. 



■i?i^>?-* 



m.'^ 



Constant for Snowdon 9 f* /Ssr? 
Cosine corrected Alt, 9*999968*5 



/« 



1 ib 33 ~ Cosine 9-9998951 
-41 20 Ait. 



y|5)34 13 Approx. dist 
3 25 Correction. 



Observed Alt. * • , 45 
Dip for 1 4 feet , * - 3 


W P 

05 

45 


4! 

Terrestrial ref. i^j of Dip + 


20 
2S 


Corrected Alt. , . .41 
Correction ♦ . , — 3 


42 

25 




n 



Constant . 
Cosine true Alt, 



, 9 -9999205 
, 9'999973! 



o 
1 



IVue Alt. 



IS 
38 



55 
17 



Cosine : 
miles. 



9-9998996 



35 38 = .35'6 = distance of object. 



* Tht? terrestrial refraction varies from | to -%% of the arc. 



- _ X Hh 



-m^ % 



r 



*^^ 




»f, I, 





P A 



»tlHl ^ 



r* 



-mt- 



45 






N 



^ 'A - 



^- wi 









C 

\ 

# 

t 







. I 



'\ \ ■:. 



V-> 



tt. • ' 




t ^ft 



^' 



\ 









B^ 



^ 

V 



i» 



■** 



^ipper 



■-? 



-^-^4 




AVPENDIX No. 5. 






Two Objects in a iiiie ( coiijuetion ) 



■ *-•«-*»-* *^^^- 



Xf 



Klo'L.t tan^-ent ^ 



ajr 




>. 






<-' 



► vCVJ- * 4 V ^ 4 4 



i4^^4«m^4 *~t^ 4-^ 



Lead in 



s 



cirk ill a 



or sk^tcK 



^ 

t 



4 

I 



i 



1 
I 



Aagle 3^il>to3: d ed 



Sim's I'i i=ht Jlnvl) 

o 



T b r 4 ■ 



20^30' .. 



D? left 



J)? ccnl r*: 



** 



n « 



. . r > ^ 4 ^ 







o 



^^ 



r^? 



upper 



If 




n? io> 



yo?' 



*f 




No. o£ aui^le 



/ 



J 



Statl 



ion , 



1 1 * J ■ » 1 



Wind 3lill 
Ciinrch 



-A 



•".'N 



1^ 



l..F*^1Vd*p*^ ^^^. 



^ I ^ n q 




i flood I - 



Direction <i£ str i:\irx 



I 



or 



I 



■- q 



■< o o 



I 



K<^co.^s,'r^' to luoor 









11* Of 



,M(i 



^t t 






-^ '^I\l 

O P 



Wllil-l of fidf 






Races aiid ovorfall ... 



V^ 



lo-vp Tv-at*^?' standard ., L,W S 



Mran water lerei 



rei. . 



M.W. L 



Rock whicli cover? ajid uncovers 



Roeks 



aiTfA.Ts ttTide?* -watej* 



4' less tKnn I f^ 

k^ i r? 

.. 2 „ 




<?S} 



« 



> 



\ 



t 





V 

^ 




5 


•ill 


^p 


■^ . 


" H 




, ** 


H i> 


m d 


L; ff 


12 d 


5^ 




^ 

^ 


<y 


it 


« 






















^1 



M 

■w 



'"H 









I 



X 



—^^^^J^ 



Appendix.*] 



HYDROGRAPHY. 




r 








t 



> 



i... 






<1 







o 






^ a 

■ 

O 



H 






a 



%4 



(/> 



Ed 

» 

(U o 
1-4 



C3 



zc 



OJ CO 

r3 lO 



c 



^* 



.CO 



Eh 



CD 



o 



en 






m 
u 

OJ 



O 



\1 









0-' 

o 






60 



I 



en 




?i^ 






i 



^ 



^>2 



S 



o 

Q 



a 



j-^ 



Q 



00 



1^ 



00 








o^ 


t:- 


*\ 


4> 


;-. 


?> 


;=! 


'1/ 


^ 


s 


o 



C5 



\i 



o 



N 



SO 
CO 



<N 



y? 




d 




t 

CD 



n3 



g 

0^ 






O 



a; 



04 






o 

03 

d 
o 






^ 
^ 



!£t 












9 ■ 

« • 
^ A •-4 



m 
M 

0} Ik 

S3 






fj^i!: 






T 



S 






CO 




Oi 
00 



c3 



03 

o 



0> 



o 



a> 



■-0 



':t^ 



I 



N 







p 



^ w fl 






d 



03 



Pk Q 



03 
P 



< 






T— It 



^i^ 



CO 



^1'^ 






-i-C^ 



-no 



G^ 









*/5to 



•-'^te 



fc^w 






CO 

CO 
CO 



ITS 









CO 



CM 






c*^;o 



^HU5 



I 




d 



^ 
M 




d 



03 



cc 



KftO 

03 
O 

d 









^ 









in 



X9 ,-1 



o 






o 0,^ 



O) 



o 



0^ 



o 









I 









^ o 



^ 






o 



« 



^ 
g 

3 



=3 
O 

^ Is 




So 
o 



0>^ 
C3 S-( 



C3 ^ 

Pi 



■ h. 



B, . 



03 '■ 



t« 



.^ tie 

o> a 



3^ 

fccJ 



.d ^ 






* . 


.'^^ 


c 




o 


$^ 


H 


qj 


t-^ 


^ 


^ 


H-a. 


03 


* • 


J 


a 




^^ 



03 



03 



^ 

^ 

H 




'A 

o 



!S' 









J 



F ^ 



/ 



/ 



100 



IIYDROGRAPIJY 



APPENDIX No. 6. 



[Sect. III. 



m-" 






•K-U 



The number of Miles or Minutes of the Equator contained in a Dei, e 

Longitude under each parallel of Latitude for the Spheroid 
S04 Compression. 



of 



Lat. 



. ^ 



H 



o 


i 

3 
4 

K 

6 

7 

8 

9 

10 

13 
14 
15 

iO 

17 
IS 
19 
20 

21 
22 
23 
24 
25 
26 
27 

29 

30 



Length of 
Degree. 



60-000 
59-991 
59-964 
59-91^ 
59-854 



59 

59 
59 
59 






7 

673 
556 
419 



59-266 
59*094 
58=905 

58-697 
58-472 

58*229 
57-968 
57 690 
57-394 
57-081 
56-751 
56-403 
56*038 



55 
55 
54 
54 
53 
53 
53 



657 
258 
842 
410 
962 
496 
015 



52-518 
52-004 



Lat. 



o 

31 
32 

33 
34 
35 

36 

37 



38 



39 
40 
41 
42 
43 

44 
45 
46 

47 

48 
49 
50 

51 

52 
53 



54 
55 

56 

57 
58 
59 
60 



\ 



: i 



Length of 
Detrree. 



475 



51 
50-930 
50-370 
49-793 
49 • 202 
48-596 
975 
339 
083 



4'^ 



t 
47 

46 



46-021 

45-346 

44-654 

43-948 

43-229 

42-495 

41-750 

40^992 

40-220 
39-437 

38-642 



37 
37 

35 



834 
015 
185 
343 



34-400 

33-627 
32-754 

3r370 

30*977 

30-074 



Lat. 



o 
61 

62 

63 

64 

65 

67 

68 

69 
70 
71 
72 
73 
74 
75 
76 

77 
78 
79 
80 
81 
82 
83 
84 
85 

87 
88 
89 
90 



Length of 
Dei'ree. 



595 



29161 
28-240 
27-310 
26-372 
25-426 
24'47I 
23-509 
22-540 
21-564 
20-581 
19-592 
18-596 
17 

16-588 
15-577 
14-560 
13-639 
12-514 
11-485 
10*452 
9*416 
377 
336 
292 
246 
199 
3-150 
2- 101 
1-050 
• 000 



8 

6 

5 

4 



1 

r 



\ 



Time' 



;U) A.: 



i 



m 



St 



9 0,. 



30 .. 



'0 „ 
I 



5 



AH 



II 






. 'I „ 



30 » 
12 " ~ 



i* 



»» 



5 



IJ 



11 



I^ESrr 



T'T 



I 



Appendix,] 



IIYDROGRAFHY 



101 



APPENDIX No. 8,— Daily Tide Jolunaj.. 



h -. 



^^' 



I 



« * 






• 4 



1- 



* ' 



'0 



i 



s 



of 

Transit^ 



18 



h. m. A.M. 



! 






^2 OirectiOEi j Velocity { 

Tc of St rf"'im of ["y) 



i =; 



1 T)'5 '^f'^nsil-. 


% 


h- 


rxx. 


P,J1 


Winds. 

1 


1 *^ 

■ V 


i * 

■ S 

- a 

; rr 




i 

i 




F 

1 
J 

r 

J 



Pi act'. 

T.nng. 






Vor. of Compass 



KEMAKKS. 



1 



IJFPKR TUANSiT. 



H. M. 

'.',{} A.M 



I'. Ail. 



Knots, j 

i 



I .• i 



^;:! 



»* 



^ 



»» 



30 
3 



99 



HO 



J' 



4 



»» 



15 



30 ., 



6 



30 



J* 



7 



*» 



I 

i 

i 



ao 



IJ 



8 



51 



30 



j> 



9 



*» 



30 



t.O 



! 
I 

i 11 „ I 



.iO 



^1 



1 



30 



*> 



I 



1 



1 



I 



I 
I 



h-- I 



1 



l:i 



1 



LCi\\iLR TRANSIT. 



ao p.M, 1 



I 
30 



♦* 



j» 



2 



»» 



30 



3 






30 



»» 



4 



»* 



3(» 



5 

ao 



6 



99 

— » r- 



30 



99 



7 



»? 



e 



30 



9 



>9 



3^) 



10 






30 



>» 



U 



»J 



■JO 



»• 



12 



99 



! 



Hitrl- 



RESl'I.TS 



I- 






! 



i 



I 
1 



i 



H- M. 



H. M. 



b* « 



Tater 

r.mv M'ater at 

■] Flood Sti jain terminated 
I Ebb ditto ditto 






A-M. 
9i 



if 





} 


1 

E 
I 




j 

i 1 
1 


t 

! 

h 
1 
[ 

1 




t 


i 


1 






A:k?itiona! OHi^en'^^tion?.- 



I 

I 

I H. M. F. U 1 

. . ' 

|. io . 

I. 20 . 

!■ SO . 

i. 40 . 

I 

, 50 . 

. , 



! n. M= p 

'. . 

J 

L 10 . 

. 20 . 

i . 30 . 

! 

• . 



From ^ hour 
before 
to ^ hour 






H. W, 



\ 

j From -1 hour 
before 

> to ^ hour 
after 



L. W. 



J 



Moon's A;?e. 



Additional Observations. 



n. M. i^. I.") 
. . 



. 10 

I. 20 

. 30 

. 40 

. 50 

. 



•. 



H. M. P. 

. . 

I , 10 . 
.20 , 

. m . 

. 40 , 

) . 50 . 
1.0* 

■ 



> 



From 4 hour 
"before 



to ^ hoar 



afttT 



lO 



Frorri ^ hour 



!. 



o^ 



to ^ h^TT 

after 



P.M. ] K!?0, A.M,, 

Fall 

Rise. F.M,» 

Fall 



feet. 



inehe*!^. 



9f 






-^j 









102 



HYDROGRAPHY, 



[Sect III. 



APPENDIX 

Register of Tides observed at Portisiied in the Mouth 



High Water. 



Datn. 



A.M. 

Oi 
P.M. 



Time. : Hei.l .!Hij;h Water. 



A=2S. 



r 
I 






h, m, 

6 3 
€ 13 
6 S3 

6 3a 



ft. in. 

43 2 : ^;-.- -95 A.M. j 
43 8 I 

43 a i £9-74 P.M. I 
43 B 

43 2 



i 


1 


i 1 




i 


1 ; 




! 


1 

E 


1 1 

J 


1 



i 

i 

i 

1 


1 

p 


1 

i 

f 


4 






f 






1 

3 






1 


p 




1 


i 




1 



I 




Appeal*' 



iVo. 



7. 



b ■ 



0.iOD^^» 



1 




or T-m*^' 



A 



1i 



I « 

I 
i 50 I 



I'.S. 



L i' 






^ . ^ 




H 



Appendix.] 



HYDEOGRAFHY. 



103 



No. 7. 



of Occober, 1847. (Observer Wm. Quin, Qr.-Mastei%) 






■■i^ 



IjOW Watkr. 



P.M. 



Time. 



Height- 






I'.M. 



h. ni. 

60 

1 00 
1 lo 
1 2u 
I 3o 



' ft. 


in- 


i 3 

4 


; 




5 ! 


i 2 


£ i 


S 


4 ; 


2 


n 1 



Range 



of 

Tide. 

ft, in. 
43 



Interpolated 
Water. 



Jj'str it. Diff, ,,, , 



Mean 



I 



Stream 









h. m. 

6 );^ A.M. 

6 3B F.M- 



I 

11 19 A*M. I 7 16 

i 



jWater 
Level. 

23 5 



1 






! 7 19 23 



-^ 






* 



North . 



2 



N-N.W, 1 






— ■a 



1 

Flood i Ebb 


6 : 12 go 

6 20 i I m 


f 

F 

w 

4 


^ 

i 
1 

^ 

1 


1 

E 

f 


1 

i 
1 

! 

i 
1 


1 

ri 


i 
s 







i 

i 




104 



HYOROGRAPHY. 



[Sect. III. 



AFP'"' 






APPENDIX No. 9. 




APPENDIX No. 10. 

To CONSTRUCT A ChART TOR A RUNNING SUEVKY OF A CoAST. 

Dp AAV the meridian line A B (Appendix No. 9) through the centre of the 
chart, and set off the degrees of latitude upon it, of equal lengths, accord- 
ing to the. scale which it is intended to construct the chart upon—draw 
short lines at right angles to each of these. 

At the extremities of the degre-.^s of latitude, as at 40^ and 45°, set off 
right and left upon the perpendiculars distance, rqnal to half a degree of 
longitude in those parallels respectively (t^^m from Appendix No. ^^ as 



r 

\ 






of *^ 



arcs 



1 



section 

the pi" 
poicts 

top or 
nect t^ 
44, 45 
parts 
give a 
gltutl€ 

merid: 

by a i 

degree 

Wh 



» 



puss 



^ - 



COAS' 



Abstj 



Thei 



T ' 




-^m 



Of thi 

havii 
<;onu 

of B 

that 

oft] 



and 



scai 



iC 



i 



I 

t 

\ 

t 



Appendix.] 



nYi>ROGRAPHT 



105 



I 



I 



^t ab c d; then \vith the dr^onal distance a d ov c h ; and with the hof 
of the compass at 40^ sweep the small arcs 1 1 at top, and likewise the 
arcs 1 1 at bottom from 45^. Again, with the length of a degree of 
loB-Itude in 40^ cut the small arcs 1 1 before described: these inter- 
sections will be corners of parallelograms, each of a degree of longitude, 
extended over as many degrees of latitude as your chart contains. Repeat 
the process for other meridians right and left of A B, and connect the 
points 1 1, &c. by meridian lines. Set off upon these from either the 
top or bottom the degrees of latitude before laid off upon A B, and v-on- 
nect them all throughout the chart by straight lines, as at 40, 41, 42, 43, 
44, 45, &c. For a scale, divide the degree of latitude iuto sixty equal 
parts, or into such equal portions of it as the scale admits of, and it will 
give a similar proportion of geographic miles of distar -^-e: and for lon- 
gitude, if each dec^f-ee of latitude be so divided by lines extending from 
meridian to meridian, and the corners of the parallelogram be connected 
by a straight line, as is shown in the plan between the list and 42nd 
degree, a scale of miles will be given for that parallel. 

When bearings are taken they must be laid off from the Meridian 

passing through the station. 



u 



\ 



■r \ 



1 f 



^' 



t 

T 



APPENDIX No. 11. 

Coasts and Islands of which our Hydkogkaphical Knowledge 

is imperfbct. 

Abstract fnma Return made to the House of Commons lOth Fehriiarij^ 

1848j/rom the Hydrographic Department of the Admiralty, 

There is wanted a critical examination cf " the eastern islands of the 
Mediterranean, along with the coasts of Syria and Egypt, and as much 
of the northern shore of Africa as would meet the French survey, which, 
having commenced with Algiers and Morocco, will very probably be 
continued along Eastern Barbary and Tunis. 

"From the Strait of Gibraltar the western coast of Africa has been 
sufficiently surveyed and published as far as Cape Formosa, in the Bight 
of Iknin: but as then^ is much legitimate traffic in the eastern part of 
that great Bight as well as further to the southward, both it and many 
of the ports and anchorages on this side of the Cape of Good Hope 
require a more car :'ul and connected examination* 

" The charts of ihe whole of the Cape colony are exceedingly defective, 
and from thence to the Portuguese settlements of Deiagoa we know 
scarcely anything. 

" From Deiagoa to the Red Sea and the whole contour of Madagascar 

F O 



2 



106 



HYDROGRAPHY. 



[Sect. Ill 



are sufficiently represented on our charts for the general purposes of 
navigation, thoivjh many further researches along the former po..t 
might still be profitably made. '^ 



■■' The Red Sc 



r 



art of the coast of Arabia, the Gulf of Persia and 
many detached portions of the East Indies, have been ah-eadv executed 
by the Company's officers ; iiad no doubt it is intended that the coasts of 
Mahibar and Coromandel shall soon be undertaken by the same hands 



1 



he long Malay Peninsula and the Strait of Malacca will require much 
time and skill to complete, and to combine v,-ith each other those parts 
that have been surveved. 

" With the China Sea we are daily becoming better acquainted, but 
much is still to be done there ; for probably not one of the multitude of 
rocks and shoals with which it is almost covered is put exactly in its 
right position ; and while some are repeated two or three tiuics, others 
have been omitted. 

" On the coast of China the charts are excellent, from Canton round 
to the moath of the great river Yang-tse-Kiang ; but of the Yellow Sea 

^'""^^'^^ '^^^ still less of the Corea, Japan, and the coast of 



we Know ver\ 



Tartary, and up to the confines of the Russian empire. 

" The southern passages into the China seas have never been examined 
with the care they deserve ; and all that is known of what are called the 
eastern passages through the Great Malay Archipelago are only the 

*^"al observations and sketches made years ago by indus- 



V, Vet/ 



results of th 
trious seamen. 



" The islands and surrounding shores of the Arafura Sea, if better 
kn ™, would offer nmny ports of refuge, and probably an increased 
opening to commerciai enterprise. 

'' The Strait of Torres has been satisfactorily surveyed; but before it 



oeco 



cientU k 



3 the great highway for steam-vessels to and from Sydney, its 
approaches, and also its contiguous coasts of New Guinea, should be 
more intimately known. 

"The whole circuit of the great island of Australia has been well 
explored, and the general characteristics of its several shores are suffi- 

known for all general purposes ; but far more minute surveys of 
Its immediate waters and maritime resources must precede their being 
mliabited, beginning with the eastern coast, along which the tide of 
colonization seems to be already creeping. 

'^ The shores of Tasmania, in like manner, are but very roughly laid 
down, and even to this day there is no chart of the harbour and entrance 
to Hobart Town, its capital aud principal seat of trade. 

'' A full survey of New Zealand has just been commenced, and will 
no^doubt answer all the wants of both the settler and nav^-rjator. 

" In advancing to the eastv/ard across the Pacific Ocean, there are 



I 



( 



rlH 



m''' 



traffic 



e 



to^ 

gurve 

del ] 

thee 

and ^ 
pres( 

surv 

ofM 
harb 

Plat: 
been 



«i 



Bare 
bed 
agai 

n < 

of t^ 

kuc 



it 



{ 



ocas 
be:, 
and 
wai 
Hu 
cha 

mul 

whi 

uav 

OhS( 

idei 



^. 



_ u _ 






1* 



'^k 



f T^ 



^^ 







V ■ 



fe: 



-ilOi :,: 



} 



1^ 



» 



i 



an L 



I, 

r 



-^ > 




iH 



%*' 



J 1 




^'«.. 



^ 



Appendix.] 



HYDROOI APHY. 






many groups of islands with w^ ,ii onr merchant-%.^^cls have occa>^ 






traffic, or m which the whaline 



•^s refit, and -^hidi ought, th 



ft-r' 



? 



to be more efficiently examined, 

^' On the opposite side of tlie Pacific some pr--res3 has been mao. m 
surveying the coast between the T ^ oi ' "ritory and the Strait of J wc 



del Fuca; but with the long * 



_ ^ _ 






,H;tw^;en the Oregon district 



W*- 



the entrance of the Gulf of Cai^ ^. .a .vi. arc very superficially acqviah.a=^. 
and but little is known of the iu - " >r of xhat extensive Gulf. In the 
present state of those countries it 
survey into their inner v^ 



-1 

u 



<-. •■ » 



3 not appear necessary to pusn our 
rs : but there u .-i be no doubt tbat the coasts 



of Mexico, Guatemala, and New Grauada, sfhich contain many valuable 
harbours and innumerable trading ports, ought to be minutely and con- 
nectedly surveyed. 



« From the Equator to Cape Horn, and from thence round to the river 
Plata, on the eastern side of America, all that is immediately ^^anted has 
been alreadv achieved by the splendid survey of Captain Fitzroy. 

" Some parts of the great empire of Brazil we owe to the labours oi 
Baron de Eoussin and of other Frencli officers ; but there is much yet to 
be done on that coast between the Plata and the Amazon rivers, and 
again along Guyana and Venezuela up to the mouth of the Orinoco. 

« The shores of the main land between Trinidad island and the Gulf of 
Mexico have been charted and published by the Admiralty ; but many 
of the West India islands are still wanting to complete a wholesome 

knowledge of those seas. 

" The United States are carrying on an elaborate survey of their own 
coasts : and to the northward of them a part of the Bay of Fundy has 
been done by ourselves, as well as all the shores of Nova Scotia, Canada, 
and Newfoundlaiid : and when these surveys are finished, we shall only 
want to complete the eastern coast of AraeL-ica, those of Labrador and of 
Hudson Bay, which, being in our possession, ought to appear in our 

charts with some degree of truth." 

As it is impossible here to open the question of the positions of the 
multitude of islands, of the Pacific especially, the apparent number of 
which has been so greatly increased by the errors of observation o. 
navigators who liave reported them, we can only recomiuend to the 
observer the propriety of fixing astronomically every island whicii he 
may fall in with, and to note any peculiarity by which it may oe 
identified hereafter. 






■J 



I 



riM"- 






.''< 






^ 



:t^ 




i 20)^ ) 



[Sect. IV, 



SEOTfO^- IV. 



m ^ 



TIDES 



BY THE JREV. Dll. WHEWELL 



Directions f)r Tide Observations. 

t 

1. In making tide observations, the main object is, in 
the first place, to refer the tides to the motions of the 
moon, by which they are, in most places, mainly go- 



verned. 



F- 



v/ 



r 



this purpose, the time and height of high water 

L 'i^-. 



■) 



this time will have to be compared with the time of the 
moon's passage across the meridian of the place. 

of the moon's transit) may be 
the common table given in the Nautical 



known 




Almanac, or in other books of the same kind. 

2. The time of high water (and low water) may some- 
times (when the sea is calm) be observed with sufficient 
accuracy by observing the surftice of the sea, where it 



washes a vertical scale fixed 
divided into 




and inches. 



in the open water, and 
The moment when the 
water is highest (and lowest) must be observed by a 
watch or clock, well regulated, or corrected for its error. 
3. In general, the waves will make it difficult to ob- 
serve the moment of the highest (and lowest) open water 
with much aecura(5v. The following methods may be 




t 



Seci 



I 



used 

watei 
wate 

be a 
carr] 

strin 

by 



a 



IS 01 

on a 



nal 



SI 



affec' 
ma) 
4. 
lowe; 

high' 

eithc 
larl\ 

If 

neitl 
ceas 

and 
hi el 



V.J 



5 

ter\ 



ev(^ 



of 
ho 



I 



> 



'j=^_ 




-u 



I 



,1 



1 



r1 



1 ^ 



fi 



■w '..,t 



-.•I 



11 



o 



^ 



! /* 



-i^ 



M' 



r ■ 



. f 



f.r ■' 



.■I'l 




t, 






Sect. 1V,1 



J 



TIDES. 



I ■ 



^ ^ r 



An up 



used to make the observations more accurate: 

rlrrht tube, open below and above, may be placed in the 

water, reaching above the high water, and below the luw 



water (or two tubes 



one for high water and one for lo 



water, if this mode be more convenient) . In this tube iv 



..4. 



( 






carry an upright rod, or else must have attached to it a 
string which passes upwards over a pulley and is stretched 
by a wcnght ; and the part of the rod or of the siring which 
is outside the tube must carry an index, which shall mark 
on a vertical fixed scale the rise and fall of the float. 



By making the tube close below, except one or more 



small openings, the motion of the waves will very little 



surf 



or 



may be observed with much accuracy. 

4 . It may happen that the moment of the highest 
lowest water is difficult to determine, either with or 
without the tube, on account of the water, while near the 
highest or lowest, stopping or hanging still, without 
either rising or falling, or else rising and falling irregu- 
larly. 

If there is a considerable time during which the water 

neither rises nor ftills decidedly, note the moment when it 
ceases to rise, and the moment when it begins to fall,^ 
and take the time half way between these for the time of 



high water. 



5. Another method is the followin 




■At 



tervals of time near the time of high water, for example, 
every ten minutes, or every five minutes, let the height 



of high water be observed, say tor Halt an noui u 
hour, and from the height so observed pick out 



the 



t 



Ijf* 



TIDES. 



[Sect. IV, 



lighest for the high water, and note the height and the 



fj TV> ^ 



U.I 



; and in like manner for low water. 
6. But the following is a better mode of dealing with 
observations thus made every five or ten mmutes. Let a 
number of parallel lines (ordinates) be drawn at intenals 
corresponding to the intervals of observations, and bomido.i 
by a line perpendiculai- to them on one side (the abscissa), 
and on these lines (the ordinates) let the observed height^ 
of the surface be set off (from the abscissa) and let a line 
be drawn through the extremities (of the ordinates). This 
line, if it be tolerably regular, will give the time of hidi 



watei 



i» * 



and if it be somewhat irregular, it 



can be 
curve, and then the time and hei'dit of 



smoothed into 

bdgh water read off. And in like manner for low vrater. 
Suppose, for example, that we have the following ob- 



servaiions of the 
minutes for an hour : 



height of the water made 



every At 



Times of Ob- 
servation . 




SO ! 35 i 40 : 45 ; 50 55 



m. 
60 



Heights ob- 
served 



11 11 



6 
11 



6 
9 



6 
5 



6 



! 



5 
10 



The selection of the greatest height (as in Art. 5) 



would give high water at Oh. 30ra. : but the general run 

of the height (Art. 6) would give the high water two or 

three minutes later, as appears by drawing the dotted 
curve in fig. 1. 

7. It IS easy to draw such curves, if we have, ready 
prepared, jmjjer rvlod into small squares, the divisions in 



the horizontal line reprcbenting hours and minutes, and 



\ 



I 



I 



( 



r 

[ 



1 



^ 



Sect 



IV 




!^ -' 



r 




ijji 



the d 




£ 



8. 

any I 
the w 
quart 
irreg] 
from 
that i 



t 



mijst: 



izi, 



case 







every 



s 



case 
perio 



\ 



( 

r 

r 



i 





^b 



Ji 



u 



s 4 



^ 1 



Ut 



r 



t 



4 



V - 



k 



• » 




I 



1'^ 

r 



Sect. IV.l 



TIDES, 



111 



H*»5ghts of Water. 



Fig. 1. 



1 




I 

1 

I 



I 



Times of Obw? 









e Qivisions ra 



th 



inches. 



* ■ • 



the vertical line representing feet and 



8. It is well to beojin a series of tide obseryation^ 



at 



^^ 



any place by observing the height of the water during 
the ivhole of the day and night every half-hour or every 
quarter of an hour. For if the rise and fall be very 

irregular, or have any features which make it ditfer much 

this means, be seen 




from the common rule, it will, 

that the case is a peculiar one, and that peculiar methods 



mv.r.t 



be used : but if there is nothing peculiar in the 
case, the common methods may be used. 

For instance, if, instead of there being two tides In 



every (lunar) day, there be one only, or four (both which 
cases occur at several places), these peculiarities will be 
discovered by observations continued during the day and 



night 



) 



m 



the 



way just 



recommended. If there be a 



periodical rise and fall of the sea's surface not depen^Sng 



^ 




112 



TIDES. 



[Sect. IV. 



in any obvious way upon the moon, the periods of maxi- 
mum and minimum should be carefully and exactly ob- 
served, in order to determine upon what the rise and fall 
does depend. This is the case in some parts of the 



Pacific, the rise and fall at those places beino- small. 

9. If the tides are tolerahly regular, it will not be ne- 
cessary to observe, except for every five minutes near the 
time of high water and low water ; say for an hour so 
as to include the exact time near the middle of the hour. 
From these observations, by laying down the heio-hts as 



ordinates, and drawing curves, as directed in Art. 6 
the height and time of high water and of low water will 
be deduced. 

10. It is desirable to compare tlie observations of the 
time of high water and low^ water with the time of the 
moon's transit (see Art. 1) wMle the observations ar(i 
goivg on : for if the tide follow this transit at very irre- 

comrnon modes of observation will 



gular intervals, the 



probably be of no use, and the time and trouble employed 



in making them wdll be lost. 



11. The time of high w^ater at any place on the day of 
new or full moon is commonly called the establishment of 



cause 



this being established, the time of 
high water on any other day may, in most cases, be 
known. 



12. But if the tides are very irregular, this is not the 
case ; and then the establishment of the place is of no 
use : or, rather, there is no proper establishment. And if 
the tides be regular the establishment may be got from 

ations made on other days, just as w ell as from those 
made on the day of new or full moon. See Note A. 




1^ - 



^I^ 



13. 

of tli^ 
riioon I 

howTi 



flioon 

cane<^ 
Su] 

high 



V 




the h 

traiisi 
are g 
on til 



1 




1S4/ 
Jan 



11 A. 
p 

P. 

13 A. 

p. 

14 A. 

p. 

A. 
P. 



15 



14 



* 



Iti 

differea, 
at Grt. 



^.- 



1. 



I 



i 



f 



L . 



L 
L 

P 

J 

I 



^ . 



ra' 



i t 



J 

I 



fi 






^ 



./^p 



^1 T 



If 



Sect. IVO 



TIDES, 



1 



1 -^ 



13, To cornpare the times of higli water witli tlie times 



UjtvO 



) tlie 



of the moon's transit (see Art. 10), we must t 
moon's transit from the tables (see Art. 1), and reckon 



ft 



moon's transit, and put down these intervals, which are 
called the lurdtidal intervals* 

Suppose, for example, that we have the observatitms of 
hi'^h water contained in the following t^ble : we add to 
them the other columns, containing the moon's trc. it and 




the lunitidal interval calculated therefrom. TliC alteri 
transits are interpolated midway between the others, which 



are given by the table. The a.m. 
on the 14th is given in the table 



-n5 






12h. 32m. on the 



13th, the hour of the table being reckoned from Boon. 



1347. 
Jan. 



i 



11 A.M. 

PM. 

12 A.M. 



Times 

of 
H.W. 

h. m. 



Times of 
Moon's 

Transit, 



Luni- 









1847, 



I Interval 



Vd 



14 



P.M. 
A.M. 
P.M. 
A.M. 



1 
I 
1 



7 
29 
53 



P.M. 

15 A.M. 

P.M. 



2 11 
2 29 

2 48 

3 3 
3 21 

3 36 



h. 

[10 
10 

[11 

11 

[0 


[0 

1 



33] 
57 

21] 

45 

9] 
32 

55] 

19 



h. m. 



Times 
of 



Times of 
Moon's 



Jan. I H.W. 



I ran sit. 






[I 42] 



i 2 


34 1 


1 

1 2 


32 


2 


26 


2 


20 


2 


16 


2 


8 


2 


2 


1 


52 I 



16 A.M. : 3 



54 



17 



18 



19 



P.M. 

A.M. 

P.M. 

A.M. 

P.M, ! 

A.M, 



4 9 



P.M. i *J 



4 

4 
5 
5 
5 



20 



1 



48 



A.M. i 
P.M. i 



6 



26 

43 

3 

23 

47 

9 

34 



2 

3 

[4 

4 

[4 
5 



m. 
6 

291 

52' 

15] 

39 

3] 
27 
51] 

In 



Luni- 
tidal 
In i er val 

h. m. 





40 




34 




28 




24 




20 




18 




18 




IS 




20 




■r^* 



14. To see whether the lunitidal intervals follow the 

* It is not necessary, for the purposes considered in these directions, 
to calculate the time of the moon's transit at the place of observation by 
differences of days. It is sufficient to take the time of the moon's transit 
at Greenwich, and to add two minutes for every hour of tvest longitude 
of the place. For the moon (on the average) moves away from the sun ^o 
tluit her distance from the sun is increased 48 minutes in time for every 
24 Itours, and therefore the transit of the moon is later at every other 
place by two minutes for every hour. 



134 



TIDES. 



[Sect. IV, 



regular law, the best way is to put them into a curve 



s^ 



fetting off the lunitidal interval belonging to each tide as 
an ordinate, as in fig. 2.* If the curve drawn through 



ol- 



Times II, W, 






I 

t 



30>n 



2Ht 



j%j^ 



. < 



\h 






T 

Jan. 11, IS, 13, 14, 15, 16, 17, 18, 19, 20 

o 

Full Moon. 



tiie extremity of the ordinates be tolerably regul 
tides may be presumed to be so. 



15. In the observations given in Art. 13 we may see 



Iiow loose a term the " estaUishment " is. The 1 3th is 
the day of full moon, for in the course of that day the 
moon is 12 hours from the sun. The time of high water 
on the 13th is— a.m.., 2h. 11m.; p.m., 2h. 29m. ; and 
either of these might, in the common use of the term, be 
called "' the establishment." 

16. If the lunitidal intervals be set oft" for a fortnight 



! 



I 



sect. 



IV-] 



or 



inoi*^ 



i. 




Thi3< 



V^y 



at any ] 

lace 1)1 

1 



P 



17. J 

of takii 

fig. 2, V 
transit ; 



./ 



J" 



6k 



^ A 

curve \ 
Oh. 



or 1 



111 



e 



In actual practir-e it -vfill be better to draw the figures on a larger 
scale than those here ^iven. 



boon's tv 



■_* 



•*;.!! 



I 



i. 



L^i - 



.r> 



i 



Sect. IV.J 



TIDES. 



115 



or more, the curve (Art. 14) will descend and ascend 
alternately every fortnight, as in fig. o. 

This curve is the curve of the semi -jmnsual inequality ; 
and when this curve has been determined by obcsrvations 
at any place, the hour of high water at any thae at that 

place may be predicted. 

17. But the curve will be better determined if, instead 
of taking for the abscissa the day of the month, as in 
fig. 2, we take for the abscissa the time of the moon's 
transit as in fig. 3.* 



Tiines H. W. 



Fig. 3 



Sh.. 



^J 



[ 



^ 



/ 



/ 




1 

* 



Jh- 



6b 



4^ 

9»' 



1^^ 



7h bb 9h i^.h \\h !*■ ^** ^'^ "^^ 

Jan. 7, 89, 10, 11. 12, 13, M, 15, 15, 17, IS 




L ^ 



i»l 



•; 



!i 



r 



\, 



lu this case the establishment is the orclirxate of this 
curve which corresponds to the time of moon s transit 
Oh. or 12h, In the figure it is 2h. 16m. 

The mode of calculating the hour of high water on 



* Since the moon's transit is about 48 minutes later every day, there 
will be along the abscissa five days of the month for ev^./ tour hours of 
moon's transit. 



116 



TIDES. 



[Sect. IV. 



any day, when the establishment of the place is known a^ 
m Art. 17, is given in Note A. 

The establishment of the place may be known by 
observation, made at any age of the moon, as well as at 
new and full moon, by the same kind of calculation. 
18. It is also advisable to set off the height of hioi. 

ordinates, and to draw a curve through the 
extremities. This curve abo will ascend and descend 

(ascending at spring tides and flpsr.,.n.1,-^„ 



Sf aJ-tC>i* clS 



at neap tides). 



nm 



■A 



Hie heights may be set off as ordinates, taking for the 

abscissas equal intervals to represent successive half-days, 
as in Art. 16. 

But tiie curve will be better determined if we take for 
the abscissas the hour of the moon's transit, as in Art. 17. 
;. The maxirmmi or greatest ordinate of this curve of 
heights (that is, the spring-tide height) follows the day of 
new and the day of full moon, by one, two, or three 
days ; and as the new or full moon is supposed to produce 
the spring tide, this interval of one, two, or three days is 



M 



called the age of the tide. 



th 



20. If the heights 



be set off from an abscissa which is 
hour of the moon's transit (see Art. 18), the distance 
of the maximum ordinate from the hour of transit, Oh. or 
12h. (which are the same thing \ wdll give the age of the 
tide more exactly than Art. 19. 

21. The lunitidal intervals and heights of low tvater 
may be laid down in curves in the same manner as those 
of high water, 

of the semi-mensual inequality of 
times and heights should be determined, when opportunity 



2. The 






f- 



, ]V-) 



rv 



So^^> 



fo- 



il 



from 



sucl 



results (t1^ 

he liT^e) . 

23. Be 

lay 1 



to « 



heights, 



c 



haiiges I 

bv the di 

For ex 

of hi.2;h w. 



t 



*(^A- 



2L In 



high watei 
tb^^ugli tl 
as in fig. = 



\. 



.1 



The 



maxi 



e wi 



Jaiini 



ifi the 



C0\] 



25.1 



lil 



fifties h 



ap 



u 



K 



k 



\. 



) 1 



^4 



I, 



I 



t: 



\ 



^ 

y 



f 



f 



Sect. IVO 



TIDES. 



117 



allows, for several 



from 






eks or months in succession: for 



such observations we can obtain 




scientific 



results (the effect of the sun, of the moon's parallax, and 

the like), 

23. Besides the changes which arc produced from day 
to day by the semi-mensual inequality of times and 



heidits, there arc at many 



pla( 



ces 



other considerable 



changes produced between the two tides of the same day 
hy the dmrnal inequality. 

For example, there are many cases in which the height 
of high water is alternately lower and higher in successive 



;.i 



24. In this case, if we set off the successive heights of 
high water as ordinates at equal int<n*vals, and draw a line 
through their extremities, this hne will have a zigzag form, 

as In fig. 4. 



Heights n.W. 



Fi^. 4. 



-. -f , 




,■ V 




i 



Jan. i, S, 3, 4. 5, r„ 7. % 9. 10, 11, IS, 13. 14, 15, 16, 17. 



J 



--.ra- 



The width of the zigzag increases from nothing to a 
maximum, and then diminishes to nothing again, general^' 
in the course of a fortnight ; and so on perpetually. 

25. In consequence of the diurnal ine(iUi-Hy, it some 
times happens that the afternoon tides are higher than the 
forenoon tides, or the reverse, for many '.veeks together 



u ^r 



118 



TIDES. 



[Sect 1 V. 



And hence, it has sometimes been stated as a rule, at such 
places, that the afternoon tides are always the highest or 
the reverse. But this is not the rule. If the afternoon 
tides are the highest at one time of the year, they arc 



lowest at another. 



the 



The rule of the diurnal inequality depends on th^ 
moon s dechnation, and will be given in Note B. 

26. There is often a diurnal inequality of ihe height 
of low water, and at some places it is greater than % 
diurnal mequallty of high water (as at Sincapore, and at 
Port Essmgton in Australia) . 

^ 27. Also there is often a diurnal inequality in the 
time«. 

When this is the case, if we set off the Imntidal inter- 
vals as ordinates (see Art. 14), the line drawn through 
their extremities will have a zigzag form, like that of the 
heights in fig. 4. 

28. When this is the case, we cannot determine the 
establishment (see Art. 17) without making allowance for 
the diurnal inequality. 



dr 



We make allowance for the diurnal inequality bv 
...... a curve, cutting off from the zigzags equal per- 



a »v J n 



tions above and below. (Sop fio. 4. ^ q^i,:„ 7- mi 

^ . "tiuw. ^^^oee ng. 4.; ling mean line will 

■" of a wavy form in consequence of the semi-mensual 
inequality ; and the ordinate corresponding to the new or 
run moon, or to the hour or 12 of moon's transit, will 
give the establishment. 



But if 



we a 



^ pply this eptablishrnent to predict the time 

- tide on any day, we must also apply the diurnal 



N 



(S 



7 



\ 



f>«t' 



b^^' 



TV.] 



29. 

that 
have 



thei 
si/! 



t 



happen 
few day^ 
are two 
should 1 



every 



h 



5 minnt( 

30. Ii 

the U h 

ticularly 

They 

observati 

These 

1. A, 
commoni 
If thp""^ 

examine, 
the objec 
area, it 

region 0: 
32. It 

flood 



an 






urns. 



w 



tu 



'ii 



rn 



e 1] 



e 



^^iistak 

observati 
^^ the ti, 
'^ the SI 



p 



(l) 



4 i1 



d 



^J^ 






rr 



ID 



A-^- 






HAR 



f 

i 



(ifii 



i 



L- 



i4 



I 



1 ■ 



1 



ifi 



/flB 



'.^t 



r 



1 



1 



;■ I'- 



Sect. IV.] 



TIDES- 



119 



^me 



that there is 07ihj one tide in 24 hours 



have single-day tides) . 



But this doe 



(and then we 
not generally 



if possible, oftener, say 



every 



happen through a whole lunation ; it happens only fo. a 
few days in each semi-lunation ; ?aid at other times there 
are two tides as usual. Ca.^es of one tide in 24 hours 
should be particularly observed, making the observations 
every half-hour, or, 

5 minutes. 

30. In some places the tide rises and falls /oi/r times in 

the 24 hours. The cases where this occurs arc to be par- 
ticularly observed. 

They may be observed, as in Art. 29, by making 
observations every half-hour, 10 minutes, or 5 minutes. 

•J 



half- 



• f 



31. A^Hiere double half-day tide 



s e 



s. 



'I 



xist, they do not 
commonly extend over any considerable lengtli of coast. 
If there be time and opportunity, it will be well to 
examine, by observation, liov/ far tbey do extend. Bnt if 
the object be to determine the laws of the tides in a larger 
area, it is better to make the observations out of the 
resion of these anomalies. 

32. It is well to observe the direction of the stream of 
flood and of ebb, and the time at which the stream 

turns. 

We must take care not to confound the time of the 
turn of the tide-stream with the time of high water. 
Mistakes and errors have often been produced in t'de 
observations by supposhig that the turn of the tide-stream 
is the time of high water. But this is not so. The turn 
of the stream generallv takes place at a different time 




U 

) 



t 



i 

\ 
I 



- + 



- i' . 



^^ 



^■> 



120 



TIDES. 



[Sect. IV. 



high water, except at the head of a bay or creek, 
am of flood commonly runs for some time 



from 

The 

often for hoiirs 



after the time of high water. 



In the 



way, the stream of ebb rmis for some time after 1 



same 



CSV 



:r^. i- 



water. 



33. The time at which the stream turns is often dif- 
ferent at different distances from the shore ; but the time 
of high water is not different at these points. In general, 
what is wanted in tide observations is the time of hicfh 
water, not the time of slack imter. 

With regard to the streams of flow and ebb, they are 
often not merely two streams in opposite directions at 
different times of the tide ; they generally turn succes- 
sively into several directions, so as to go quite round the 
compass in one complete tide; either in the direction 
N. E, S. W. (with the sun), or N. W. S. E. (against the 
sun). It is desirable to note which of these ways the tide- 
stream goes round, as this fact may help to determine 
which side the tide- wave comes from. 



One 



tide observatioi 






one place to another. 
This 



is to trace the progress of the tide from 



i may be done in some measure by determining the 
estaUishments of a series of places in the region which 
we have to consider. For these establishments, reduced 
to Greenwich time by allowing for the longitude, give the 
time at which the tide is at each place, and hence its 



progress. 



35. The progress of the tide may be conceived as the 



progress ot a verv wide wa 
to each place in succession. 



8 






Sect 



IV 1 



Ijut* 



the 



Avatt 



motion < 

of the 
hen th 
'hen th 



w 



36. 1 



determii 
and 35), 



01 



f] 



age 

Art. 1 7 £ 

37. In 



usmg 



the 



better to i 

all the liii 

For the 

the tide {i 
Th 



e me 



40m, less i 
age of the 
38. Wh 
made for 

^"•'ctiiess t 

, 3^- But 

Wd.f, 



r 



ei 



,-1 



' ^ 



*4 ! "^^r^ 



for; 



1 



'-'1 



For 



Y. 



sueh 



' "^^«of.i. 



^■av 



'^sto] 




\ 



f 



^1 



»•. 



r\t^ 



■**-. :-•' 



IV* 



1 » 



i -^ -, 



rtfii*> 



m : 




^ -i 



^ ■ 



fT' 



,Dd ^-^ 



*-\ 



^ 



the 



Sect IV.] 



TIDES. 



121 



But the motion of tbis rwe-wave is not that motion of 
the water which makes the stream of flood. Nor docs the 
motion of the wave coincide with any motion of the parts 
of the water. The tide-wave may be going one way 
when the water is going another^ asliappens in some rivers 
when the tide is travelling upwards in them. 

36. The establishment^ which is wanted in order to 

L 

determine one progress of the tide-wave (see Art. 34 



^>^ 




T 

Pi 






and 35), may be known from observations made at any 






age of the moon, as well as at new or full moon, (See 
Art. 17 and Note A.) 

37, Ii. tracing the progress of the tide-wave, instead of 
using the vulgar estahlishmeM hitherto spoken of, it is 

better to use the mean estahlishment^ namely, the mean of 
all the liinitidal intervals. 

For the vulgar establishment is affected by the age of 
the tide (Art. 20), which the mean establishment is not. 



Th(^ mean establishment is (say) 10m., 20m.5 30m., or 
40m, less than the vulgar establishment, according to the 
age of the tide, (See Note A.) 

38. When the tides are regular, good observations, 



made for a few days or a week at each place, may give 



the establishment (either vulgar or mean) with sufficient 
exactness to determine the progress of the tide-wave. 

39. But the progress of the tide-wave may be much 
better determined by means of simultaneous ohservations • 
namely, observations made at different places on the same 
days for a few days or a week. 

For such a purpose persons must be posted at difE^rent 
points of the shore or shores where tLo motion of the tide- 
wave is to be traced ; say 10, or 20, or 40, or 80 miles 

G 



*' 



109 



TIDES. 



[Sect. IV 



r 



Sect 



from each other, as may be convenieiiL They must 
observe the tides at these places on the same days, morn- 
ing and eveningj by the methods already described. Tlie 
times of high water at the different places on each half-d ay, 



being compared, will give the progress of the tide-wave. 



40. In order to trace the progress of the tide-wave still 
more widely, the observers described in the last article, 
after having made the observations there spoken of, mav 
be removed to new positions of the same kind, and thus 
trace the tide farther. 

When this course is adopted, it will be well to liave one 

standard station, at which tide 



(or more) fixed or 



observations are constantly made ; and the observations 
made at any time at any other place may be compared 
with those made at the standard station. 

4L The tides which take place far up deep bays, 
sounds, and rivers, are later than the tides at the entrance 
of such inlets ; but they are not more irregular : on the 



contrary, the tides in such situations are often remarkably 
regular. 

42. The progress of the tide-wave up inlets may be 
determined by the method described in Art. 39. 

43. The tide in its progress up inlets and rivers is often 
much maernified and modified by local circumstances. 

s it is magnified so that the wave which brings 




the tide at one period of its rise advances with an abmpt 
front of broken water. This is called a bore (as in tL- 
Severn^ the Garonne, the Amazons River). 



S 



ometinies the tide is divided into two half-day tides in 
its progress up a river (as in t^<^ Forth in Scotland). 
In all cases, after a certain point, the tide dies away 



m 



1 » 




ascenamg 






p 

( 



f 



r 

p 



4 

beei 
6,11 



give 

in t 
4 



an i 



lun 



C 



aver 

nil. 

P.M., 

place 
(Tht 

aboil 

T! 
of th 
same 

47 

the ti 

althoi 

effect, 

48. 
baroix 

■k incl] 



-V, 



Sect l\.] 



TIDES. 



12 




I 



h 



i 



hr 



k 




f" 



I •■' 



)\ 



I 



44. The tide observations made at any place, when th 

■m 

times and heights of high water (and of low water) have 
been deduced in the way directed in Articles 2, 3^ 4. 5, 
6, may be entered in a table of wliich the form will be 
given, and must then be sent to the Hydrographer''^ Office 
in the Admiralty. 

45. It is to be remarked that^ though there is generally 



an A.M. and a p.im< tide, there is one day in every half- 
lunation on which there is only one tide. 

(Because the interval of the two tidvo is, on the 
average, about 12h. 24m. ; so that if there be a tide at 



llh. 50m. A.M., there will be no other tide till 12h. lAm. 
P.M., that is Oh. 14m. a.m. of the next day.) 

46. Self'iegistering tide-machines are used in several 



places, and may be constructed at no great expense. 
(They are made by Mr. Newman, of Regent Street, for 
about 30/. : they are constructed so as to work with a tube 
and float, as described in Art. 3.) 

These machines give the whole course of rise and fall 
of the tide j and record several successive tides on the 
same paper. 

47. The wind often produces a considerable effect upon 

the tides, especially upon the height, and should be noted, 

although it is difficult to give any general rule for the 
effect. 

48. The surface of the sea rises and Mis as the 
barometer falls and rises ; namely, about 1 inch for every 
h ii^ch of mercury. This may be applied ;is a correction 
when very exact observations are made. 




»e 



G 2 



■f^ 



124 



TIDFS 



[Sect. IV, 






APP 



"*h 



V 



NOTE A. 

Note to Akticles 17, 19. and 37, 

To find the Hour of High Water on any day, at any place, tvhen the 

Establishment of the place is known. 

The rule is different (as to amount) according to the tidal force of the 
sun : for though the tidal force of the sun in theory is the same at all 
placcSj it is found by observation to be different at different places. 

This difference appears in the different ratio of the rise of spring- 
tides to the rise of reap-tides : (this difference is the semimenstrual in- 
equality of heights.) In general the rise of spring-tide is abou^ double 
that of neap-tide, which gives the solar tide one'tldrd of the lunar tide. 
But in some cases the spring-tide exceeds the nea])-tide only by one-third, 
"which gives the solar tide only one-seventh of the lunar tide. 

Also the difference of the greatest and least lunitidal intervals (that 
is, the semimenstrual inequality of times : see Art, 13 and 16) shows the 
difference of the solar tidal force at different places. The difference of 
the greatest and least intervals is 1 h. 28 m. at London and Liverpool, 
but at Plvmouth it is 1 h. 36 m„ and at Portsmouth 1 h. 21 m. On the 
coast of North America it is generally less than 1 h. 20 m., while at 
some places on the coasts of France and Ireland it is above 2 h. 

We niav take 1 h. 28 m. as the mean value of this difference, which 
agrees with the supposition that the solar tide is about one-third the 

lunar tide. 

In finding the hour of high water on any day when the vulgar esta- 
blishment is known, the rule will also be different according to the age 
of the tide= We shall give the rule M'hcn the tide is a day and a quarter 
o!d, and also when the tide is two days and a half old. In general, the 
tides will be between these limits. 

(L) Tide a day and a quarter old. Minutes to be added to or sub- 
tracted from the establishments^ according to the hour of the moon's 



transit on the half-dav in question t 



Hour of the Moon's 

Transifc after Su 



Correction of the vul- 

^y^ r-* ablishment 
to find the Lunitidal 
Interval . , . 








m. j m. I m. 



161 



Oi 

*.>-: 



I 

J 



i 



47 --57 



-60i-47 -16 +15 



4-2?! + 25 



?*!■ 




For example— if the establishment be 2 h, 27 m., at what hour will tiie 
high water come after a moon's transit which takes place at 4h. a.m.? 
The minutes to he added to 2 h. 27 m. for 4 h. transit are. by the table, 
- 57 m.: therefore the high water will be at 1 h. 30 m. after the moon's 
transit^ that is, at 5h, 30 rn. 



■^2 






I 



He 



Cc 



1 

val 

thai 
posi^ 

li 



of 



c< 



Art. 



.A- -. 



■^e 



Ti 



fron^ 
respc 
thret 

(3 



\ 



s 
I 

T 



a 



Tl 
the 

val 2 

oft hi 

there 

and t 



On 

^'^niti 

difr^..- 



-^^ 
«- 

^ 

^ 






)■ 



4 "'* 



(1 



1 ^ 



i«*^ 



INF' 




Ti ff 



N.- 



' 1 . 

1 ' 




r 

L 






Appeiidix.] 



TIDES. 



125 



(2.) Tide two days and a half old: 



Hour of Moon's Transit 



Correction of the Ksta- ) 
blishmeiit • . , ( 




h. i h. 



2 


3 




1 

1 


m. 


ra. ' 


-31 


4 J^ 1 




i 

h. I h 



' 7 









o-^\ 



I 



w. 




j h. i h. 

I 10 n 






Uui + JO 



t 



T* 



This table is to be used in ti}e same way as th^ othei 

IJence we see that the age of the tide most affects the lunitidal inter- 
nal when the time of moon's transit is between 7 and 8 hours.* 

The mean lunitidal interval, or ivean establishiwnt, is IG minutes less 
than the former, and 31 minutes less tl'^n the latter establishment sup- 
posed in the above tables. (See Art, 87.) 

If the tides are observed for a semilunation, or any com.plete number 
of semilunations, the mean lunitidal interval, or mean establishment (sec 

7), Will be found by taking the mean of all the lunitidal intervals 
observed. 

The lunitidal interval corresponding to any given distance of the moon 
from the sun may be found by the follo>ting table. But the tide cor- 
responding to the given distance may not really occur till one, two, 
three days later, according to the age of the tide. 



Art. 3 



or 



(3.) Correction of 7?ieau establishment. 



^_ 



Hour of Moon's Tran--v 
sit (1, a^ 3 days pre- > 
ceding) , , . , ; 

Corresponding Cor- 
rection of Mean La- 

nitidaUnterval , , 







p 
i 


h. 


i ; 2 1 3 


1 i 


i 

* 

1 



h. 



ni. 





m, m. 

-K) -3i 



m. I m. . 
-41 -44 



I 








h. I h. 

10 ; 11 



m. I in. m. 

+ 31 +44 +4 



-•1 



+ 31 



1 

i 



m. 

+ lfi 



i 



? 



This table may be used ^f hen we know the age of the tide. Thus, let 
the age of the tide be a day and a quarter, and the mean luTiitidal inter* 
val 2 h. 11 m.; let the moon's transit take jplace at 4 h. ; then at the birth 
of the tide, a day and a quarter earlier, the transit took place at 3h. 
therefore the correction of the lunitidal interval is, by the table. - 41 m., 
and the interval so corrected is 1 h. 30 m., which, added to 4h., the time 
ofmoon'stransi* jives 5 h. 30 m. as the time of high water. 

To find the Estahlishment at any place when the Hour of Hiyh Water on a 

given day is observed. 
On the given day, the time of moon's transit is known- and hence the 
lunitidal interval ; and, by the above tables, the correction by which this 
differs from the establishment is known. 

• Hence it is desirnlle to make tide observations in the first and ^ourtli quarters of 
the moon, rather than in the second and third quarters. 






^!^^- 



^- -r*- --^J - 



26 



TIDES. 



[Sect. IV 



Thus, if high water occur at 5 o'clock when the tinie of moon's transit 
is 3h., the luxiitidal inter val is 2h. ; and the correction (if the first table 
be applicable) is — 47 m. ; hence the establishment is 2 h. 47 m. 



\ 



Sect, 



\ 



NOTE B. 

Note to Akticle 25. 

The Rule rf the DiAtrnal Inequality. 
The Diurnal Inequality depends upon the moon's declination, as has 
been said already. It increases from up to its maximum, and de- 
creases to again, as the declin. on does so; following these changes at 
an interval of one, two, or three- days, accordinc? to the aee of the tide. 
The rule is expressed in this way : 
For north declination of moon, 

Add to the tide following moon's south transit ; 
Subtract from the tide following moon's north transit. 
For south declination of moon, 

Subtract from the tide following moon's south transit; 

Add to tlie tide following moon's north transit. 
The south transit is the miperior transit in the northern hemisphere, 
and the north transit the inferior. The ccmtrary is the case iu the 
southern 




Form for Tide Obs£rvatioks, 



Tides observed at 



, Lat, 



Long, 



By 



Mode of observation 



ivlode of deducing H. W. and L. W. 



/Fixed scale in open water ? 

{ Tube with float ? 

I Self-registering gauge ? 

r Mere looking ? 

lOrdinates every 5 m. near max. ? 



1348. 



Hi^h Water. 



1 I 

Low Water. ! Wind. 



Month. I Day. iHr^^ht. j Time. 



Height. ! 



I 



I" 



1 A.M. 

2 A.M. 

3 A.M. 



,-,, ; Barom. jTransit. 

Time. ' 



I 






V 

I 
Moon*s*|LuTiitidal ' 

Interval, 

H. VV. 



\ 









• These colum:;:? to be filled at leisure (see Art. 13, 41). 



I 



to ^' 

attei 



gent 
as tl 
then 
mu3i 

neee 
bool 

the 



i 




i 



tioii 

and 
the 

cann 
occu; 

but 

wh 



A 



en 



^ffoi»( 







Tr 



Sect. V. i 



( 127 ) 



-i, 



Section V. 



GEOGRAPHY. 



By W. J. HAMILTON, Esq., Pres. Tx.G.B, 



*l 



% 



■jgjfl^ 



i 



Before alluding particularly to the individual objects 
to which, in reference to Geographical observations, the 
attention of travellers should be more immediately di- 



rectc 



/^ 



(1, it may be, perhaps, expedient 



general points which should be constantly borne in mind 
as the basis of all observations, inasmuch as without 
them, all individual remarks, however carefully made, 
must be desultory and unsatisfactory. 



Most 




the 



necessity of acqmring a habit of writing down in a note- 



book, either immediately or at the earliest opportunity, 
the observations made and information obtained. Where 
numbers are concerned, the whole value of the informa- 
tion is lost, unless the greatest accuracy is observed ; 
and amidst the hurry of business or professional duties 
the memory is not always to be trusted. This habit 

r 

cannot be carried too far. A thousand circunibtances 
occur daily to a traveller in distant regions, which from 
repeated observation may appear insignificant to himself, 
but which may be of the greatest importance to others, 
when brought home in the pages of his note-book, either as 
affording new information to the scientific inquirer, or as 



128 



GEOGRAPHY. 



[Sect V, 






corroborating the observations 
^^^e means of iudaing between 
of former travellers. 



of others, or as aifordino' 
the conflicting testimonies 



It is also important, in order to t^ecure accuracy, that 
the observations should be noted down on the spot 
It is 



dangerous to trust much to th 





;t, or contmeut, or 



3 memory on such 
subjects ; and if the observation be worth makinjj, it is 
essential that it be correct. And here it may not be 
inappropriate to hold out a caution against too hasty 
eneralization. A travelh-r is not justified in concluding 
that because the portion of a 
island which he has visited is wooded or rocky, or other- 
wise remarkable, the whole district may be set down as 
similarly formed. lie must carefully confine himself to 
the description of what he has himself seen, or what he 
has learned on undoulrted authority. 

Again, to the geographer, the constant use of the com- 

No one attempting to give 



greatest 



& 



graj. 



s 



fhould 



ever be without an 



instrument of this kind, as portable as is consistent 
with correctness. The bearings of distant points the 
direction of the course of a river, however tliey may be 
guessed at by the eye, can never be accurately laid down 
without the compass ; and these should be immediately 

This and his compass 



transferred 




the note-book. 



should on -ll occasions be his constant and inseparable 
companions. In using the former, he should not forget 



that slight sketches of the 



country, and of the peculiar 
forms of hills, however hastily and roughly made, will 
often be of more assistance in recalling to his mind the 
features of the district he has visited than lonn and 






P' 



P 



n 4 



Sect. V .] 



OfiOGKAPHlT. 



129 



elaborate descriptions. Let liim tlien acquire the habit 
of never quitting his ship without his note-book and 



tnpas 



') 



and alth.ough at times it 



■e 



may seem 3 



irksome to have to remember and to fetch 



these materials, the traveller, if he acquires the habit of 
constantly using them with readiness, will never have 



:gret 



J 




himself before start- 



Ha\ 



e 



arisen m proviuir 
sful companions, 
these few introductory remarks 



'5 



i s 



hail 



proceed to describe as briefly and succinctly as possible 

some of the principal features to which the attention and 

the inquiries of the young geographer should be chiefly 

directed. For this purpose I propose dividing the subject 

into two heads, which, without straining the use of words, 

may be not inappropriately called Physical and Political 

Geography. By physical geography I mean everything 

relating to the form and configuration of the earth's 

surface as it issues from the hand of nature, or as it is 

modified by the combined effects of time and weather, 

and atmospheric influences. By political geography I 



would wish to imply all those facts which are the imme- 
diate consequences of the operations of man, exercised 
either on the raw materials of the earth, or on the means 
of his intercourse with his fellow creatures.^ 






1 



I 



«-# 



^ 



* Au lUiliau writer of considerable eminence, Count Aimibale Eanuzzi, 
in a little Avork publisbed at Bologna, 1840, entitled * Saggio di Geografia 
Pura/ divides geography into t-^o brancLes, -wliicli he calls pure and 
Stat ;eal , ography: the former professes to describe the results of 
physical forces, the latter the eiiccts of moral force; the termer is ex- 
pre^seu by measurement, the latter by numbers. 

g3 



130 



GEOGRAPHY, 



[Sect. V, 



I. Physical Geography. 



1. 



The principal heads under which this branch of the 
subject may be divided, and respecting each of which it 
will be necessary to say a few words, are 

Form of country ; whether consisting of hills, valleys, 
or plains, 

2. Mountain ranges; their direction, height, spurs, 
woods, and forests. 

Rivers : their sources, obstacles, size, affluents, and 
confluents. 

4, Springs ; whether hot or cold or mineral, their 






localities, temperature, &c. 

5. Lakes, marshes^ la<yoons ; how surrounded, &c. 



banks 



nature 



rocky, or muddy 



Form of country 



or plains. — The 




figu 



first object which engages the attention of a traveller on 
entering a new locality, and this may be described in 



ndulating, hilly, or mountainous ; or 



general term 




the country may I. divided into districts, to each of which 

configuration may be applied. 



one of the abov 




or 



Each of these, howeyer, is susceptible of great modification. 
A flat country may be a sandy de&crt, a rich alluvial plain, 




or a marshy, boggy tract j it may be well watered 
rivers and streams, or arid and parched up ; it may con- 
tain numerous lakes ; it may be barren or wooded, or 
cultivated as arable or gra land: each of thes<; fea- 
tures may he of importance, or at least of interest ; nor 
must the nature of its soil be omitted, whether sand, or 



> 






^.J 



J 



* * 



^t- 



l*>*^ 



It 



. 1 



i 



\ 



^ 



f 



Sect, v.] 



GEOGRAPHY. 



131 



marl, or clay, ?-s the appearance of the country will often 
depend greatly on this circumstance. Another important 
characteristic is its general form and extent, and the 
natural features by which it is hounded, whether moun- 
tains, rivers, or seas; how many miles wide, and how 
many long ; whether extending parallel with the coast, 



or running up between hills into the interior. 



Manv of these characteristics, it will be observed, 
belong equally to the other forms which constitute the 



count 



nav b 



character of tlie district. An 

barren, wooded, or cultivated ; it may be arid, or watered 

by streams, &c. The undulations may be abrupt, or only 

gently swelling, and this may be in a great measure 

owing to the nature of the subsoil, whether it consists of 

gravel, or sand, or rock ; but a country of this description 

is easily described, A hilly country, on the other hand, 

is more comphcated. Not only is the term vague and 

uncertain, but other features have to be considered. 

Neither hills nor mountains can exist without valleys, 

and these also deserve to be considered and described. 

Then, again, the hills themselves m-ay be of various 

forms and characters ; do they extend in long parallel 

chains or ranges, or are they detached and isolated ? Do 



they radiate or converge ? 



Do they rise abruptly or 



gradually from the low country? and how are the}' 



wooded ? 



W 



do the rocks 



which constitute their 



nucleus con?ist of ? If possible, it is desirable to ascertain 
their height, which, in the absence of complicated instru- 
ments and barometers, may be very fairly obtained ap- 
proximatively by marking the exact point at which pure 
fresh water boils. Of course the same accuracy cannot 



I 



1 



132 



GEOGRAPIiy. 



[Sect, V. 



P 

r 



or smootli and 



be obtained as with the barometer, but much may be 
done with the help of w^ell -graduated thermometers. 

2, Mountaiii ranges. — The most important features in 
the configuration of a country are the mountain rano^s bv 
which it is traversed. The exact point of distinction be- 
tween a hill and a mountain is difficult to describe : in 
some cases it will be purely comparative, in others it will 
depend on the general character of the country, and in 
some it will be arbitrary. But in all cases it will be de- 
sirable to endeavour to ascertain the height of the princi- 
pal points, the direction of the main ranges or chains, 
and whether they are parallel or not. The ridges also 
may be serrated O'agged like a saw), 
even, and the summits themselves will be either pointed, 
or dome-shaped, or flat. Is the mountain insulated or 
not? and if so, is it conical and sloping on all side_ 
to the surrounding plains, or does it consist of a detached 
ridge ? Many of these points will be found to dep(^nd on 
the geological formation of the country, and this branch 
of our subject is very closely connected with that science 
It is also desirable to ascertain how far the mountain 
tops are covered with perpetual snow, and how far down 
their sides snow lies during the whole vear. Is th 
marked difference in the slope on the one side or on the 
otiier ? Does vi;getatioii abound more on one side than 
on the other ? e.g. in Asia Minor all the mountain r.n-es 
which extend from E. to W,, and this is their principal 

on their northern flanks with luxu- 



s 



ere "'ly 



direction, are covered 

riant v cgctation and magnificent forests, while the southern 
flauks, exposed to the rays of an almost tropical sun, are 
void of vegetation, barren, and generally rocky. Here, 



\ 



I 



(- 



t 



r 



b 

b( 



t 



-^^ 



t^ 



1 « 



t 



:!■ 



*^ 



Sect, V,] 






GEOGRAPHY, 



16 



nq 

V f 



-.i^ 



/ 



again, we trench on the province of the botanist ; and yet 
the geographer should inquire how far vegetation extends 



up the 



mountain side, and what 



are the changes which 



it undergoes. How far is it influenced by the change of 
soil, or the abundance or absence of springs ? Nor can 
we complete our information respecting a mountain chain, 
unless we know the len<zth to which it extends, and the 



breadth of country which it covers. 

Valleys are a necessary complement 
masses, and there are many peculiarities connected with 



to 



aiountam 



• *i 



them well deserving observation. Are the side 



^^ 



preci- 



pitous or sloping ? are they wide or narrov/ ? well watered 
or arid ? wooded or barren ? Do the rocky sides corre- 
spond with each other in their salient and re-entering 
angles ? How far do they extend into the bosom of the 
mountains? and how are the subordinate vallevs con- 
nected with the principal one? But there is another 
peculiarity of valleys not to be lost sight of. There 
are some which convey to the traveller the impression 
that ho is passing tlirough a mountainous or hilly country, 
so steep, rugged, and lofty are the hills by which he is 
surrounded. It is only on reaching their summit that he 
becomes aware that the country through which he has 
been passing is an extensive plain, or table-land, inter- 
sected by deep chasms and valleys, cut through the soft 
soil by the constant efforts of the streams by which it is 
traversed ; such valleys of excavation as these have been 
sometimes not unaptly called negative valleys. 

3. Bivcrs .—Scarcely less important than that of moun- 
tains is the effect of rivers in modifviusr the seosra- 



*_-^ 



o"'-& 



phical configuration of a country. From their sources in 






L 

I 



134 



GEOGRAPHY 



[Sect. ¥• 



f 



S. 



the iiiountain 



recesses to their final disemhogulng in the 
sea, their course, their currentSj and their shores afford 
an endless variety of remarks and ohservations. The 
depth and colour of the water, the rate at which it flows 
the eddies and currents hy which its course is marked, 
are all deserving of notice, as are also the rocks and 
shoals which obstruct its uniform progress, either inter- 
fering with its navigation, or, by projecting beyond its 
ordinary banks, throwing back the rushing torrent on the 
opposite shores, as has been so eloquently described by 
the Latin poet : 

Vidimus flavum Tiberim, retor 
Littore Etrusco yiolenter undisj 
Ire dejectum monumenta regis, 

Tempiaque Vestse 

thus causing the gradual fall of the cliffs by undermining 
their precarious foundation. Nor in describing the size 
or extent of rivers should we neglect to state how far up 
they are navigable, to what vessels, and by what means, 
whether the mouth is constantly free, or whether closed 
by a bar, and how mvich water there generally is over it. 
Some rivers, however, are not only closed by a bar, but, 
as in the case of Western Australia, are, during periods 
when the water is low, completely masked by the sand- 



hills or dunes which are blown up, forming a continuous 



bank with the hills which skirt the shores, and onlv when 
freshets of more than ordinary force come down are these 
sandy barriers overthrown^ and the rivers enabled io 
find an uninterrupted outlet. In other cases the effect 
of beaches thrown up bt the constant set of currents in 
one direction is not so absolutely insurmountable, the 
streams are only partially deflected from their prop 



\ 



\ 



\ 



* I- 



ly 



er 



^>M > 



I 



^ l\\ 



K'i 



-4 






1 

^1 



K.^ 



\ . 



I t 



1 .-, 



f 



ft 



I ^- 



s 






^ 1 



■1- 



1 



, ,t1 



'f 



H iA- 



' 5. 



Sect. V,] 



GEOGRAPHY 



X a 



■3 ^-_ 



course, and instead of flowing id to the sea in a continued 
line, are compelled to run for some distance parallel to 
the coast, imtil the accumulated backwater has acquired 
sufficient power to overcome the diminished resistance 
of the sea-beach : this, however, more properly belongs 
to the consideration of the coast line. 

But the description of a river will be imperfect, unless 
we also state the number and character of the streams 

r 

which fall into it. And here we have to consider the 
angle at wliich the rivers join each other, whether the 
direction of the main stream is altered or not by the 
junction, the relative size of two confluent streams, and 
which of them may be said to preserve its former course 
with the smallest deviation. On the true description of 
these details must depend the question as to which of two 
confluent rivers should be considered as the main or parent 
stream. Rivers are said to be confluent when both 
branches are nearly equally deflected from their former 
direction, and that of the united streams may be said to be 
the resultant of two contrary forces. An affluent is a stream 
which falls into another called the recipient without chang- 
ing the direction of the latter, and entirely losing its own. 



.- 1 



r 



^_,u. 



1 .. 



Ic 



i*^ 



1 



C'^' 



'1 




.f 



a and b are conlluent streams, d is an affluent failing into c, the recipient. 






-rz- 



136 



GEOGRAPHY. 



[Sect. V. 



An affi uent, too, may generally be said to be smaller 
than its recipient, and may often be more correctly called 
a rivulet or a torrent ; and here it may be remarked that 
there is great advantage in attending to the true and 



proper use of these relative terms, rivers, torrents, rivulets 
or brooks, the two latter being more or less synonymous 



and a torrent being generally applied to a rapid mountain 
stream ; all these, more or less, bring down detritus from 
the hills, w^hich is deposited at the mouths of the streams 
or wherever other natural causes retard the rapid flow of 
water. In these cases deltas are formed, which deserve 
examination, and are either fluviatile, lacustrine, or ma- 
rine, according as the river empties itself into another 
river, a lake, or the 






But there are other important characters which deserve 
attention in the description of a river; and chiefly the 
name is of importance. Does it change 



durin 



h 



:re and wiien ? How far up from the mouth is the 
same name preserved ? and is it the same on both banks ? 
What is its origin, and by whom, was it first given ? Then 
we must inquire what islands are met with in its course ? 
Where are they Bituated? Are they low? subject to 
inundation ? marshy or rocky ? or do they stand high 
above the level of the stream ? Are they cultivated or 
not ? What are their natural productions ? By what 
creatures are they inhabited? Again, is the river at all 
affected by rapids, or shoals, or cataracts ? and what are 
the peculiar characteristics of these impediments to nan- 



cation ? 



Does the tide flow in them 



5 



and huvv far np 



* 



See Col. J, J, Jackson's work, *What to Observe/ London, 



I 



) 






I 



Sect 



fer 

roc 
riv 

ill 



pp 

ob 

liu 
sul 

vol 



aci 



ill 
nej 

wl; 
rei 

Se 



*"i 



nci 



po: 



on] 
the 



12 mo., 1841. 



S1Z( 

whi 

arid 



^^ 



-fw.^--- 



^.c^ 



I 

t 



Sect. V, 



- i 



GEOGBAPHY. 



137 



^ ■ 



■\ 



"*fc 



h 



\\ 



J' 



r 



•iRu 



1 



•^-i 



*T-A 






t 



t 



i- 



f 



f 



f 



rr' 



p> 1 



i 



Vi 



1 - 



V 



f 



I;Oli 



1^' 



( 



is it felt ? Does tlie river abound with eddies or whirl- 
pools, and how are they occasioned? Do they inter- 
fere with navigation or not ? Are they accompanied by 
rocks or shoals ? Again, we must ascertain what fords a 
river offers, and what depth of water is generally found 



over them : the nature of the bed of the river, particularly 

in the case of a ford, should also be carefully ascertained. 

In addition to these remarks, many other important 

peculiarities will often be 
observer. In some countries, particularly in 
limestone districts, the rivers are remarkable for their 
subterranean courses.* Suddenly emerging in large 



disco 



vered bv the careful 

secondary 



volumes from the base of a lofty mountain, they flow 
across rich alluvial plains, and are then as suddenly lost 
in the cavities of another mountain, again to issue forth to 
the light of day in a distant region, after their subterra- 

Nor should the traveller omit to notice, 



nean course. 



when crossing a river^ the direction in which it flows as 
regards his own course, whether to the right or to the left. 
Several distinguished travellers have been unable to con- 
nect their observations from not having attended to this 



point. 



Sp 



•The phenomena connected with the out- 



bui-sts of water from the surface of the earth are not 
only of the greatest interest, but a correct observation of 



them is attended with the greatest practical advantage. 
The traveller should state, approximatively at least, their 
size or volume, and the nature of the rock or soil out of 
which they rise ; also whether they are pure or mineral, 
and what deposits are formed about the orifices through 



* c^ 



tyria and the neiglibouruood of Trieste. 



t^"T^t 



-^ ^* 



138 



GEOGRAPHY. 



[Sect. V. 




which they issue ; how they are affected hy diiFercnt sea- 
sons ; whether they are of ordinary temperature or ther- 
mal, and if the latter, it is desirable to ascertain the 
degree of heat by means of a thermometer : the touch 
alone is a very vague and uncertain guide. It is also 

when it can be done conveniently, to procure 
specimoRs, in closely sealed bottles, of the water of such 
springs as appear to possess mineral properties, or to 
contain salts in solution, for the purpose of analysis at 
home. Naval officers whose ships are at hand have in 
this respect great advantages over those whose only means 
of transport is on horseback or on camels. 

5. Lakes. — These sheets of water varying greatly in 
size, form very important features in the geographical 
description of a country, and the traveller should care- 
fully remark their connexion with the other hydrogra- 
phical features of tlie district. AVhether they constitute 
the sources of rivers, or are their ultimate recipients, 
whether they are or are not connected with the ocean or 
other great seas, their levels with regard to the ocean, 
particularly when at a lower level, what rivers flow into 
or out of them, and whether they are fresh water or salt. 



I 



than 



marks from Colonel Jackson's work, who says 



a 



J 



re 




With 
ard to lakes in general, the observations to be made 

upon them may be comprehended under the following 
heads : 

" Name ; geographical and topographical situation ; 
height above the level of the sea, and as compared to 
oilier neighbouring lakes ; subterranean communication ; 
form, length, breadth, circumference, su^-face, and depth : 



( 

t 



i 



I 



r 



I 



X 






tliei 



renc; 



a 



the* 
the 

cilia 

poll- 
tion 

yet ^ 

and 
fairl 

C 

less 



SF'' 



mar 
com 



be 



C( 



peril 

mail 

feat 
be i 



1 



6. 



I 



the 
one 
subd: 



i' 



w 



L 



'<* 



I.. 



^ 



r 



4 



I 









I > 



r. 



■i S 



ti: 



I ^ 



i 



1 



Sect. V,] 



GEOGRAPHY. 



139 



t 



he nature of the bed and of the borders ; the transpa- 

iolour, temperature, and quality of the water ; the 



rency, c 



affluent streams and springs ; the outlets, the currents ; 
the climate, soil, and vegetation of the basins ; the heigbt 
and nature of the surrounding hills when Ihere are any ; 
the prevailing winds ; the mean ratio of evaporation com- 
pared with the quantity of water supplied ; and any parti- 



cular phenomena; the navigation and fisheries 



of 



■«' i ; 






TT^!' 



J ins 



1^4-i-.- 



.tter 



lake ; formation and desiccation of lakes/' 

point, depending as it mainly does on the relatiTe eleva 



country 



/. 



sa: 



tion or subsidence of the 
almost to belong to the kindred science of geologj'. and 
yet it bears so immediately on the physical configuration 
and geographical features of the country, that it may 



fairly be mentioned in this place. 
Connected with the question of lak( 

less important features of lagoons 

smaller hollows called ponds ; the extent of these 

marshes and lagoons should be ascertained, also whether 



and 



are the scarcely 

and 






t 




connected with the sea or not ; and what poi tioiis of them 
become dry and passable during the sunniier or other 
periods of the year. Peat bogs, in many cases the re- 
mains of former lakes, may also be classed amongst these 
features, and their extent and depth and qualities should 
be ascertained. 

6. Line of coast, Sfc. — This may be indeed said to be 

fhp TiPPiilinr nrnvinpp nf ihp- njivnl nffipf*r ! but aS forming 



one of the chief boundaries of those c^reat geographical 



subdivisions, the details of which we have been here 
alluding to, we must not omit a brief allusion to some 
of its most important features. And 1st, with regard 



Z- f 



140 



GEOGRAPHY. 



[Sect. V. 



gect^ 



-■i 



-^1 



m 



to the actuiil line of coast itself, the traveller should 



remark the various headlauds jutting out into the sea 
as well as the deep hays and recesses running up into 
the land, and affording refuge from the dangers occa- 
sioned by the neighbouring headlands ; all gaps and 
breaks in the continuity of hills or cliffs, or mountain 



ranges, the occurrence and nature of rivers and streams 



eniptying themselves into the 



sea, the 



character and 



extent of their mouths, the nature of the detritus and allu- 
vial matter brought down by them, and whether or not 
delta 



s a' 



re formed near their mouths. In another aspect 
he should inform us whether the coast is. bold or flat, 
whether formed by cliffs or by sloping plains, and whether 
the rivers enter the sea by one or by numerous channels ; 
whether the coast is clear from danger, or whether sunken 
rocks and reefs render more than usual precaution neces- 
sary in approaching it ; whether the sea deepens gradually 
or suddenly, and whether there are any extensive shoals 
or sand-banks. Soundings also may be given when prac- 
ticable, as well as the nature and colour of the sand, clay, 
or other substances brought up from the bottom by the 
lead. Do these appear to belong to the same formation 
the adjacent mountains, or to have ])een carried thither 



as 



by tides or currents, &c. 

The nature of the shore, also, should be carefully 
ascertained, whether it consists generally of sand or mud, 
or rocks, eitlier in the shape of reefs, or occurring as de- 
tached blocks, also whethci the landing is easy or not on 
th 






ch, and whether this consists of sand or shingle. 



te 



as 




of refusre ? What is the nature of the 



t 






J 

i 



and 

and 
ava' 



P 



lei 
1 



sics 
nee 
des 

tha 






mei 

bee 

the 



som 
gre? 

wiu 



mg 

sub 
or c 

the 

lan( 
Hnr 



Ar 



e 



are 

undi 

%ri; 
Usua 



-*J 



»f» 



u ^ 



t 



k 



I 



i 



^ 



I 



Hi- 



Sect, v.] 



GEOGRAPHY 



141 



ancliorage ? Are there aiiv harbours along the coast ? 
and liow far have natural harbours been rendered more 
available and safe by the erection of breakwaters or 

piers ? 

In concluding this portion of the first division of phy- 
sical geography, I would also mention a few points con- 
nected with the physical ff:^atures of the country which 
deserve notice, but which, being of an aceidenta 
than of a normal character, did not easily find a place in any 
of the natural subdivisions of the subject. The traveller 
should always pay particular attention to those pheno- 



t" 




raena in the physical structure of the country which may 
be called by some persons natural curiosities. 



Amongst 



the principal of these are grottoes, caves, and caverns ; 
some of them are not only strikingly beautiful, but of 
great scientific interest. They are more usually met 
witli in limestone districts than in any other ; it is interest- 
ing to ascertain their size and extent, and tlie distance to 
which they have been traced. Are they traversed by 
subterranean streams, and if so, do these streams enter 
or escape by known channels or mouths, as is frequently 
the case in Istria and Carniola, and in the west of Ire- 
land? Natural bridges present another instance of this 
khid of phenomena. IIow have they been formed^ and 
what is the nature of the rock of which they consist? 
Are they stalactitic, or of a more compact nature ? Mines 
are also to he noticed, although they come more directly 
under the head of geological observation. All volcanic 
phenomena and earthquakes are also deservdng of notice. 



m 



usual occurrence ; and any information respecting them 



j-^a- _A^^^ iX' ■* H^^t^ 




_> -€-^ 



142 



GEOGRAPHY. 



[Sect. V. 



effect of the frcsli water on the surrounding ocean. 



m 



is always desirable, such as the depth of water and the 

Any 
instances of that remarkable phenomenon observed 

Cephalonia, where the sea-water flows inland into a hol- 
low in the rocks, should also be carefully described. 
In short, it may be safely asserted that there is no single 
fact connected with the physical structure of the earth 
falling under the notice of an intelligent observer, which 
may not be of value or import,ance either to himself 
or others, if he will only give himself the trouble of care- 



fully noting down the main facts on the spot itself, with 



as much accuracy and detail as circumstances will permit. 
With this view we must again ui'ge what was stated at the 



be 




O 



Mr 



" Trust nothing to the memory ; for the memory becomes 
a fickle guardian when one mteresting object is succeeded 
by another still more interestins." 



IL Political Geography. 



"^ 



s now proceed to notice some of the principal fea- 
tures to which attention should be directed on the subject 
of political or statistical geography. In many respects 
this branch of our subject approaches very closely to that 
of statistics, to the considerytion of which a distinct and 
separate article will be devoted : we wall however endea- 



vour to steer clear of collision, by confining ourselves to 
; definition already given, and by avoiding those ques- 



4-1 . . 



tions of detail which are more pucab*arly the province 
of the statist. Nor can it be expected that the 
casual visitor should devote to the examination of docu- 
ments and books the time that is necessary to arrive 



i 



I 



f 



i 



s 



ect' 



^ 



* 



at an 



or 



to 



howe' 






!-■ 



w 



yhicl' 



self o: 

presei 

Tb 

into t 



1. 

3.' 

4.: 

5.. 



6.' 



1. 

on;' 



fV 



'*4VJ 



J i 



mere 

mean 



s 



it 



cani 



first 



"Ol 



and 



P 



anig 
equal] 

to bef 









r 

r 

■-r 

I 



*. 



I ■ 






f 



«1 



{ 



F* 



^ . 



J - 



I 



1 f 



H 



1 



a 



lA 



e 



4 



\ 



^ * 



.-^n V 



fti i 



# 



Sect V,] 



GEOGRAPHY. 



143 



at any important results in reference to these questions, 
or to make miieli progress in the investigation of a subject, 
however important^ the whole value of which depends on 



the extent and minute accuracy of its detail : but yet 
there are many matters connected with man's social state 
which the traveller may easily elucidate by availing him- 
self of the opportunities thrown in his way, and carefully 
preserving the information he obtains. 

This branch of our subject may properly 
into the following heads : 






divided 



1. Population ; different races of inhabitants. 

2. Language ; words and vocabularies. 

3. Government ; ceremonies and forms. 

4. Buildings ; towns, villages, 

5. Agriculture ; implements of labour and peculi 

of soil. 

6. Trade and Commerce. Roads, and other means of 





communication. 



1 



« 



Population. — One of the most interesting inquiries 



on visiting new countries relates to the people by whom 



they are inhabited. It is not enough to ascertain the 
mere amount of population, although even this is by no 
means easy ; and unless obtained from official dut^uments, 
it cannot always be relied on. The oral information 
first obtained by a stranger is almost invariably incorrect, 
and particularly so in barbarous countries and amongst 
an ignorant population, where truth and accuracy are 
equally disregarded. Various sources must be referred 
to before we can venture, in such cases, to place confi- 
dence in our information. Another and more intorestina 



I 



r 

\ 









^t^- 



I 



i 



44 



GEOGRAPHY. 



[Sect. \ 



question, as regards the population of a country, is the 
nature- and character of the races by which it is inhibited • 



Wf^ 




they 
reat races of the human family, or to a mixture of 
several ; how far the Fiatioijal character has been affected 
or modified hy such mixture ; whether it took place hiw 



ago, or 



is an event of recent occurrence- I 



n many in- 



stances, casual intercourse with tlie natives will lead to 



ntoi^m 



^E^r ^^ ■ ' ^^^ T ^^^^t ^^B ^^^^ ^fe ^P V ^A H E ^f ^1 J C ■ 4 H 

to have been preserved, which, after making due allow- 
ance for exaggeration and prejudice, will generally give a 
clue to the details required. It is also worth noticing, 
when the population consists of various races, whether one 
race or nation is more confined to a rural or a town life 
than the other ; whether there exists any feeling of hos- 
tility or jealousy between them ; whether any particular 
trades or occupations are more exclusively practised or 
followed by one race than the other ; whether one race is 
kept down or oppressed by the other, or whether they cn- 
jo\ a state of comparative equality. 

When the population of a country has up to a certain 
period consisted of one race, and a mixture has subse- 
quently taken place, this change may have been occasioned 
in three different ways. The new race may have come 

down with force and violence on the original inhabitants 

and 



M ■ 

aving gained possession by right of conquest, may 
lave constituted themselves the m.asters of fhe country ; 
, secondly, they may have been introduced as slaves in 



the first instance, captured in war or taken by stratagem 
by their more successful neighbours ; or, thirdly, they may 
have come gradually, few at a time, witli the free consent 



I'i 



L' 4 



I 



Ml 



f.l 



o( tli 



i^iiJ 



& 



fiU'J''* J 



■i 



Intel ^ , 
uuitetif 



I*. 



!' 



ni 



-'ha'* 

odc-s b 
In ma 

tie. i ^ 
characte 



tr 



^"like 



progrcf-^ 

iliey p^. 

they rer 



'l' 



P 

or th 



e 1 



flaolm' 



■ '-■ aOU: 

and r- 



lion ? 



tbese 



q^ 



tri 



all of 



^ ^'^-i 



-% 



iL 






1 



Ul^; l-^ 



b~v 







'-iV' 



• •> 



% 





iii 



1 



kJ- 



J 



f 



i/ 



*. n 



4l 



Sect, v.] 



GEOGRAPHY* 



145 



of the inhabitants, seeking to make their fortunes in a new 
country as settlers or as colonists. Any information on 
these points, where a mixture of races does exist, will be 
interesting. Not only will the moral character of the 
united people be differently influenced, but even their 
I '^litical rights, their institutions, and form of government, 



will have been greatly modified according to the different 
modes by which the union of the two people was effected. 
In many cases, too, the traveller may have opportuni- 
ties of making useful observations respecting the general 
character and disposition of a people. Ai-e they of a 



? 



Have 



warlike or a peaceful disposition / 

progress in the arts of civilization or of commerce ? Do 



B 



Ar--^ 



they possess any and what extent of literature? 
they remarkable for their honesty, or for contrary pro- 
pensities ? Are they open and frank towards strangers, 
or the reverse ? Do they make any distinction in their 

*V7 do they 



12m 



s? H 



dress and live? What are Uieir domestic habits and 
relations? Do they encourage or prohibit polygamy, 
and are women treated with respect and considera- 
tion ? Without going profoundly into the study of 
these questions, the attentive observer cannot fail to pick 
up many interesting details and facts on these subjects, 
all of which may hereafter be of 
others, 

2. Language. — The traveller will have many opportuni- 
ties of collecting much interestina information respecting 



use 



the languages of those countries which he visits, by taking 
note- of all the peculiarities he may have an opportunity^ 
of observing respecting them, when he feels confidence in 

H 



*' 




i 



146 



GEOGRAPHY. 



[Sect. V. 




the accuracy of his information. These observations do 
not of course apply to the languages of Europe, and to 
those of the more civilized nations of the East, viz. the 
Arabic, the Persian, orMahratta, &c., but are rather in- 
tended for th- guidance of those who visit the islands of 
the Pacific, or the Indian Archipelago, AustraHa, Afiica, 
an^. other lands, of which the languages are still unknown. 
In this respect there will in all probability be crreat 
analogy with the previous subject. ^^Tiere a nation has 
sprung up from the mixture of two races, it will gene- 
rally, if not universally, be found that the language bears 
traces of the same admixture, xlnalogous elements of 
combination will have produced an analogous result in a 
language partaking of the essential characters of those 
of which it was composed. Any information, therefore, 
showing how far the grammatical construction of the 
resulting language or particular words are derived from 
one or the other of the parent tongues, will be important. 
Nor should these observations be confined to mere words, 
and their affinities in different languages. It is eijually 
desirable to obtain information respecting the genius and 
character of languages : to remark how ftir the idioms of 
one correspond with those of another ; and whether the 
resemblances observed between the languages of various 
nations can in any way be traced to any original con 
nexion between the nations themselves, or to politic^ or 
commercial relations existing between them at a former 
period. 

But it is not alone with reference to the corapar:: -ns 
to be made between diiferent lanoruages that it is desir 
lb] e tx) obtain correct information. Even when the tra- 



f 



i 



CJpct 



ve 



II 



ti 



he 
one 

ma 

wo 
pre 

all 
anc 

bar 



son 



reg] 
thei 

aiC'" 

the 
coni 
thej 
mer 

for\ 

the 

colic 

nieiii 

visit, 
taiiie 

head 
^ellej 

f 






Sect. V.I 



GEOGRAPHY. 



147 



V 



Ap 



I . . 



rf 



1 




\ r 





^ X 



-^* 



f 



i 



ganglia ff 



he may collect much valuable matter by attention to anv 
one in particular. Above all things let him endeavour to 
make as complete a vocabulary as possible of all those 
words, of which he can depend on obtaining the true and 
precise meaning. Nor are words alone to be attended to : 
all peculiarities of diction, all idiomatical expressions 
and phrases ought to be remarked and carefully written 
down. With respect to the languages of many bar- 
]>arous yet interesting people, it is only by the repeated 
oh -rvations of successive travellers, and by the com|)ari- 
son of such observations with those of others in different 
regions, that we can at last obtain any idea of their nature, 
their genius, and their origin. It may also be useful to 
ascertain how far foreign words have been introduced into 
the language, and to what extent they are used, whether 
confined to one or more classes of the population — whether 
they are more particularly used by the military, the com- 
mercial, or the manufacturing classes. 

3. Government —It is hardly to be expected that those 



lave 



for whom these remarks are principally intended will 
the time or opportunity to make many inquiries, or to 
collect much correct information on the details of goveru-- 
meut in its various branches, in the countries they m.av 



visit. M 



s, 



even if they could be ob- 
tained, would be more appropriately noticed under the 
head of Statistics. There are, however, several points 
connected with this subject on which an intelligent tra- 

hardly fail to make useful and interesting ob- 



veller 



servations. 
fo 



Amongst these we may mention all kinds of 
rms, ceremonies, and processions, whether of a reiigioos 

h2 



se' 






GEOGRAPHY. 



[Sect. V, 



I 



S 



e^ 



t 



i 



or civil natui*e ; the observance of religions rites, where 
strangers are nut superstitiously excluded ; the ceremonies 
and processions which are generally a part of such rites, 
and which for the most part take place in the open air, 
afford many opportunities for remarks. Royal pag(^ants 
and processions, military manoeuvres and encampments, 
the dress and bearing of the troops, are all worthy of 
notice. 



Many 



municipal 



institutions necessarily come 
under the observation of travellers, as matters of poHce and 
surveillance, passports and other documents required by 
the authorities, as w'ell as any other regulations nec^^^ary, 
or supposed to be so, for the maintenance of peace and 

and how are they 



order. W 




^Nhli k 



leaned, and on what articles arc they imposed? 
the principle of taxation— direct or indirect? Pubhc in- 
stitutions, also, in those countries w^here the state of society 
warrants their existence, and can secure their continuance, 
whether maintained by the liberality of the state or sup- 
ported by the zeal and resources of individuals, may w^^ll 
deserve a passing notice, even if more detailed information 
is not accessible. These, too, may be of very different 
characters, and iiiay have various objects in view : theym^y 




lor 



the promotion of liteiature amongst the 
old, or of education amongst the young j they may tend to 
the furtherance of trade and commerce, or they may only 
look to affording amusement and relaxation. Something 
at least on all these subjects will not escape the eye or 



ear of the most casual observer 



4, Buildings. — In cons 




-mg 



the buildings of a 



people, they present themselves to oui 
several points of viewc 



notice under 



We may, in the first 




£ice^ 



[ 

V 

\ 



\^ 







di 



t,. 



tri 



I 

1 

! 



! 



■^IS I; 
t 



^■. r 



i 



I 



nf 



5 



I" 




A 



r 




t 

p 



m 



xT 

A 



» 




L 



Sect, v.] 



GEOGRAPHY. 



149 



consider them as public or private. Amongst the former 
we shall find such as belong to the nation generally, either 
as the residence of the sovereign, or as belonging to the 



different departments of the executive government, or to 
the legislature, or as devoted to the alleviation of sulFeriug 
or to the maintenance of health, as poorhouses, hospitals, 
and infirmaries of various kinds. They may be devoted 
to the service of God, or to the deities worshipped by un- 
civilized nations, as churches, temples, mosques, and other 
similar edifices ; or they may be intended for the advance- 
ment of literature and science, such as colleges and imi- 



versity buildings, museums, 



picture ;_, 



calleri 






&c. ; 01 



erected for the amusement and recreation of the people, 
or for the furtherance of public business^ as market-places, 
town-halls, theatres, &c. "vVith regard to private resi- 
dences, the different purposes are not so numerous ; but 
even here we mav distinguish the habitations of the rich 
and of the poor, and those intended for town or country 
residences ; the different styles of villages in the country, 
and the character of streets and houses in the towns ; villas 
farm-houses, &c., and, in some cases, the different dwell- 
ings of different tribes. This, in the case of those nomadic 
people mIio still dwell in tents, is very remarkable. 



? 



Again, we may consider the buildings of a poviple either 
with regard to the degree of civilization of which they 
may be considered as the evidence, or to the progress 
in art and architecture which they may be held to indi- 
cate. For this purpose, not only is it desirable to point 
out the style in which they are erected, but also the ma- 
terials which have been used, and the mechanical 



con- 



trivances by which they have been assisted. In this case 



»v 



150 



GEOGRAPHY. 



[Sect. V. 



slight sketches will often (iODvey a clearer idea of the 
object than long and minute description. Nor should 
we neglect altogether another class of buildings, partly 
private and partly public in their nature, which often con- 
vey much information with respect to the character and 
progress of a people . I mean their tombs and other 
sepulchral monuments erected to the memory of the dead 
or for the purpose of preserving their bodies. It may be 
observed that few things indicate more directly the pro- 



gress o 



icgr 



civilization than the successive changes which have taken 
place in the style and character of their buildings, and of 
the arts by which they have been embellished, from the 
first rude attempts of Druidical and Cyclopean structure 
to the more elaborate and symmetrical proportions of what 
may be called the Palladian style. Any information of 
this description which falls under the notice even of the 
mo.^t hurried traveller cannot fail to be prodnctive of 
great interest. 

5. Aariculture. 



— ^The geographer will have numerous 



opportunities, in his examination of a new country, of ob- 
taining much valuable information on this and its col- 
lateral subjects, by a little attentive observation and a 
few concise imiuiries. Amongst the chief points to which 
ins attention should be directed, we may mention the use 
of tools and agricultural implements, for the purpose 



either of cultivating the soil or of transporting its produce 
from one locality to another, the mode of ploughing and 
preparing the land for different crops, the manner of 
reusing the crops themselves, of sowing, planting, and 



transplanting, of reaping and gathering in the crops, of 



t 



P 



P 



I 



Is 



3 



S 



I 



I 



L 



Sect, v.] 



GEOGRAPHY. 



151 



threshing, and other similar cccupations, the rotation of 
crops, and whether, and under what circtimstaiices, more 



than one crop is raised in the year. 

Other inquiries may be usefully directed towards the 
animals used for agricultural purposes or domestic eco- 
nomy, in the field or in the farm-yard ; whether they are 



indigenous, or brought 



from 




or neighbouring 



countries; to what uses they are applied, whether for 
draught, for food, or for clothing. How are they fed ? 
Are they of a hardy or delicate constitution ? Have any 
chano-es taken place of late years in the state of agricul- 
ture and tillage? Is it in a course of progress or de- 



cay 



? What is the feeling of the hihabitants towards 
it ? Is it practised by the majority, or only a small por- 
tion of the population ? What buildings form a part of 



.s 



s, 



agricultural capital? farm-houses, barns, and cottages? 
All these depend on the social state of the inhabitants. 
Is the pursuit of agriculture esteemed or despised ? What 
are the usual prices of provisions— animal and vegetable ? 
To which do the inhabitants give a preference ? What 
the principal produce of the country— vegetahles, fruit 
cercalia, meat, or poultry ? What is the tenure of land ? 
Is it distributed in large estates, or subdivided into small 
properties ? Is it chiefly in fee, or held on long or short 

leases from year to year ? W 
arable, meadow grass, or woodland ? What are the re- 
spective quantities of each ? What is the nature of the 



chief feature 



soil, and what distinctions are there in it ? Is one kind 
more adapted for one species of cultivation than another, 
and whence is this dilFcrence derived, and by what natural 
causes has it been occasioned or modified ? 



1 



i 



'9 



f^ 




^ 



1 






GEOGHAPHY. 



[Sect. V 



Sec 



6. Tj 



Our information respecting 
a country cannot be complete without some knowledge of 
its trade and commerce, and the manner and the means 



by which they are carried on 



In this respect, also, without 



ery 



tails of the resources and means of a country, the tra- 
vellers for whom we write can add much to our informa- 
tion by the mere recording of the facts which come under 
their own observation. What is the nature of the trades 



led 



and by different tribes, when such exist ? Are they prin- 
cipally employed in working up the raw materials pro- 
duced in their own country, or those imported from other 
quarters ? Are they workers in metal, and whence are 
the metals obtained ? Or are they workers in leather and 
similar materials ? Or do they sjiin and weave, and what 
are the materials worked up in their looms—whether wool, 
cotton, flax, or silk—and which, if any, of them are raised 

and from what other districts do 
es when requisite ? Is their corn- 



own 



J 



their 



merce 



foreign 



is it carried on ? What are the principal articles of im- 
port and export ? Wbr-re do they come from, and whither 
are they sent ? What is the medium of exchange ? What 
progress have they made beyond the mere principle of 
barter ? Is money used as a medium of exchange ? What 
coins are known? Have the natives any knowledge of 
bullion, paper, or bills of exchange? Have they any 
system of credit or bill-discounting ? How is commerce 
conducted? Yihat are the means of communication 
water or land ? If bv water, what is the nature of their 



1 



sbi 
riv 

If 

tb 
bi 



b 






ai 

of 



USi 



COT 



are 



pm 



rel 



i 



son 
its 

and 
out 

tiqi] 

totj 

may 



1 • 



tbei 
citi^ 

and 
«idif 



I 




^rl 



41 i 






1>ft . . ] 



• 1 



^} 



»» 






c 



1 



J 



1 



Sect. V,] 



GEOGRAPHY. 



153 



ships and vessels? Are they employed at sea, or on 
rivers or canals ? What is the character of their sailors ? 
If by land, have they yet learnt the use of railroads ? 



A\^ 



Are 



they available for carts and waggons, or only for beasts of 
burthen ? What beasts are used— horses, mules, asses^ 
bullocks, or camels? Which are most useful? How 



oadi 



Are they in good or bad condi- 



tion? Are the bridges well built and well kept up? 
What is the ordinary rate of travelling, and the expense 



of carrying goods? What ar(3 the weights and measures 



used in the country? Are they the same in trade or 
commerce as in private life ? Many of these questions 
are easily answered, and all v/ill be found useful for one 
purpose or another. 

There remains one subject on which it may not be ir- 
relevant to make a few remarks, although there may be 



some question as to whether this is the proper place for 
its introductioue Our information respecting distant lands 



and their inhabitants cannot be said to be complete with- 
out some knowledge of their past history and their an- 
tiquities ; and we therefore propose briefly pointing out 
to the traveller a few of the points to which liis attention 
may be advantageously directed. In the first place, in 
his excursions in the country, let liim carefully examine 
the sites and remains of ancient buildings. This identi* 
fying of ancient positions, and fixing the names of ancient 
cities, has not unfrequently been Ccxlled comparative geo- 
graphy, as establishing a comparison between the ancient 
and modern state of things. Where the remains appear to 
indicate the site of a ruined city, let him carefully trace 

h3 






154 



GEOGRAPHY. 



[Sect. V. 



the line of the ancient walls, ascertain the position of the 
gates, describe or sketch the stjle of architecture, and 
state the materials of which they have been built. If the 
fallen fragments indicate the site of a temple or analoo;ous 
Iniilcling, let the traveller endeavour to obtain precise 
measurements of its different component parts, the length 
and diameter of the columns, the details of architraves, 

may 



^'^^-' and cornices, and whatever other features 



ca.piTals, a 



attract his attention. Above all things, let him diligently 

senrch for inscriptions, and then carefully copy all that he 

may find, endeavouring as much as possible to preserve 

the precise form of the characters in which they are 
written. 

Two or three other evidences of ancient art or historv 
remaan to be noticed — coins and manuscripts, and works 
of art. With respect to the former, he cannot be too in- 
dustrious in collecting all that his means allow him to pro- 
cure of those which come in his way — taking care, of 
course, in those countries where such practices obtain, 
that he is not imposed upon by forgeries. Manu- 
scripts are of more rare occtirrence, but even these may 
safely T>e collected when possible, and there is less danger 
of deceit than in the case of coins. With regard to works 
of art it is more difficult to lay down any precise rule, on 
account of their greater variety, and a certain degree of 
vap;uepeR^ attaching to the term, and also on account of 



their 



Ik 



cost. 



T 



classes, however, may be 



mentioned which particularly deserve attention— statues 
and nrems. Of the former 



of these, the traveller 



w 



ill 



their ^viQ 



generallv be enabled onlv to make dra-wings: 

will in most cases prevent their beino; moved. Gem 



s. 






\ 



\ 



r 



'■i^x 



■ ^ ■ 



I 1 



(,- 



i 



-I 



Sect, v.] 



GEOGRAPHY. 



155 



I 



^ » 



I 



intaglios. 



aro 



on the other hand, whether cameos or 
amongst the most valuable and portable works uf art 
which a traveller can collect. But let him beware of im- 
position: nowhere is it more frequently and more noto- 
riously practised. With due attention to these liintSj the 
traveller whose fate or duty may lead him to the shores 
of classic land, cannot fail to obtain much information 
which will prove not only a source of interest to himself, 
but will be received with satisfaction and delight ^ 






\ * 



every cultivated mind on his return to his native shores. 



\r 





r 



^-1 



I 



\ 






L-d^ 



156 ) 



[Sect. VI. 



Section YI 



GEOLOGY. 



.-M 



Bx CHARLES DARWIN- Esq., FE.S,, F.G.S. 




A PERSON embarked on a naval expedition, who wishes 
to attend to Geology, is placed in a position in some 
respects highly advantageous, and in others as much to 
the contraiy. He can hardly expect during his compara- 



tively short visits at one place, to map out the area and 
sequence of widely extended formations ; and the most 



important deductions in geology must ever depend on 



this having been carefully executed ; he must generally 
confine himself to isolated sections and small areas, in 
which, liow^ever, there can be no doubt many interesting 



facts may 



r 

if 



collected = O 



other 



hand, he is ad- 



mirably situated for studying the still active causes of 
those changes, which, accumulated during long-continuod 
ages, it is the object of geology to record and explain. 
He is bo 

r 

formation 



S imve 



the ocean, from which most sedimentary 
been deposited. During the soundings 
which are so frequently carried on, he is excellently 
placed for studving the nature of the bottom, and the 



distribution of the living organisms and dead remains 
strewed over it. Again, on sea-shores, he can watch the 
breakers slowly eating into the coast-cliffs, and he can 



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Sect. VI.] 



GEOLOGY 



157 



examine 
li 



thei^ action under various circumstarxces -. he 
..I's^s that going on in an infinitedmally small scale, 
wh*'ch has ^.laned do^Ti whole continents, levelled moun- 
tain-ranges, hollowed out gi^eat valleys, and exposed over 
wide areas rocks, which must have been formed or mo- 
dified whilst heated under an ( aormous pressure. Again, 
as almost every active volcano is situated close to, or 
within a few leagues of the sea, he is admirably situated 
for investigating volcanic phenomena, which m their 






striking aspect and simplicity, are well adapted to encou- 
rage him ill his studies. 

In the present state of the science, it may be doubted 
whether the mere collection of fragments of rock without 

ietailed observations on the district whence they 



some t 



tc, can hardly be considered of any 



are brought, is worthy of the time consumed and the car- 
riage of the specimens. The simple statement that one 
part of a coast consists of granite, and another ^of sand 

stone or clay-sla 

service to geology ; and the labour thus thrown away 

might have been more profitably spent, and thus^ saved 

the collector much ultimate disappointm.ent. 

generally recognized that both the sedimentary rocks, and 

those which have come from below in a softened state, 



It 



IS now 



are nearly the same 



over the whole world. 



A mere 



fragment, with no other information than the name ui the 
place where collected, tells little more than this fact. 
These remarks do not at all apply to the collection of 
fossil remains, on which sulyect some remarks will pre- 
sently be made ; nor do they apply to an observer col- 
lecting suites of rock-specimens, with the intention oi 



himself subsequently drawing up an account of the struc- 



» 



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r^_ 



15.^ 



GEOLOGY 



rrt 



Lrfect. VJ. 



ture and succession of the strata in tlie conntries visited 
For this end, he can hardly collect too copiously, for 
errors in the naming of the rocks may thus be corrected, 
and the careful comparison of such specimens will often 
reveal to him curious relations which at the time he did 
not suspect. 

In order to make observations of value, some reading 
and much careful thought are necessary: but perhaps 



uo science requires so little preparatory study as geu- 

and none so readily yields, especially in forei.Tn 



log}. 



countries, new and striking points of interest. Some of 
the highest problems in geology wait on the observer in 



distant regions for explanation ; such as, whether the sue 
cessive formations, as judged of by the character of their 
fossil remains, correspond in distant parts of the world to 
those of Europe and North America, or whether some of 
them may not correspond to blank epochs of the nortli, 
when sedimentary beds either were not there accumu- 



lated, 



or have been subsequently destroyed. 



Again, 



with 



whether the lowest formation everywhere is the same 

that in which living beings are first present in the 
countries best known to geologists. These and many 
other such wide views in th.^ history of the worid are 

open to any one, who, applying thought and labour to his 

subj ' ■* 

quented countri 

A 




'^ 



has the good fortune to geologise in little fre- 






person wishing to commence geology, is often de- 
terred by not knowing the names of the rocks ; but this is 
a knowledge, he may rely on it, easily acquired. With 
half a dozen named crystalline rocks, or even by pa- 
tiently familiarizing his eye (aided by a lens) to the 



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Sect. VI. 1 



GEOLOGY. 



159 



aspect of the feldspar and quartz in granite, lie ^^ ill know 
tlie two most essential ingredients in most igneous rocks ; 
and in granite he will often find the glittering scales of 
mica replaced by a dark green mineral, less hard than 
the feldspar and quartz; and then he 



will Know me 



Ti 



ledi- 



thlrd most important mineral, hornblende. 

mentary rocks can hardly be described, except by the 

terms in common use : impure limestone, which cannot 



be readily recognised by the eye, can be distinguished 
by its effervescence with acids. By the repeated compa- 
rfson of freshly fractured sedimentary and igneous rocks, 
such as sandstone and clay-slate on the one hand, and 
granite and lava on the other, he will learn the difference 
between crystalline and mechanical structure ; and this 
is a very necessary point. Let no one be deterred from 
geology by the want of mineralogical knowledge ; 
inany excellent geologists have known but little ; and 
from this reason its value has perhaps sometimes been 
underrated, for many of the obscurer points in geology, 
such as the nature of the metamorphic changes in rocks, 
and all the phenomena of metallic and other veins, 
almost require such knowledge. The appearances pre- 
sent. J by the different forms of stratification (that is, the 
original planes of deposition) may be soon learnt in the 
field ; though no doubt the beginner would be aided by 
the diagrams given in many elementary works. 

The two most useful works which the geologist can 
carry with him, are without doubt the ' Principles ' and 
the ' Elements of Geology,' by Sir Charles Lyell. He 
should procure a treatise on mineralogy, for instance, 
' Philhps's Mineralogy,' by Allan. If he has the oppor- 



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160 



rt 



GEOLOGY. 



[Sect. VI. 



H 



Tlieoretical 



from discussing many of the questions which ought esi)e- 
cially to engage the attention of a sea voyager. As he 
will probably visit many volcanic regions, Dr. Daiibeny's 
' Treatise on Volcanos' would be extremely useful ; and 
a list is there given of special treatises on the volcanic 
countries likely to be visited hy him. The ' Description 
Physique des Isles Canaries,' by Von Buch, may be cited 
as a model of descriptive powers. The voyager in the 
Temperate and Polar regions ought to have Agassiz' 
work on Glaciers. 

The geologist fortunately requires but little apparatus ; 
a heavy hammer, with its two ends wedge-formed and 
truncated ; a light hammer for trimming specimens ; some 
chisels and a pickaxe for fossils ; a pocket-lens with three 
glasses (to be incessantly used) ; a compass and a clino- 
meter, compose his essential tools. One of the simplest 
clinometers is that constructed by the Rev. Prof Henslow : 
it consists of a compass and spirit-level, fitted in a miall 
square box ; in the lid there is a brass plate, gradu- 
ated in a quadrant of 90 degrees, with a little plumb-line 
to be suspended from a milled head at the apex of the 
quadrant. The line of intersection of the edge of the 

clinometer, when held horizontally, with the plane of the 
stratum, mv 



V_/ 



M>5 lf 



^ -■* 



y^ 



strike, range, or direction ; and its dip 



or inclination, taken ... right angles to the strike, can be 
m.easured by the plumb-line. In an uneven countrv, 
It is not easy without the clinometer to judge which is 
the iu... of greatest inclination of a stratum ; and it is 
always more satisfactory to be certain of the angle than 



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Sect. VI.] 



GEOLOGY. 



161 



to estimate it. A flat piece of rock representing the 
general slope can usually be found, and by placing a 



note-book on it, the measurement can be made very ac- 
curately. In studying the cleavage or slaty structure of 
rocks, accurate observations are indispensable. A mouth 

a book with instruc- 



s, and 



blow-pipe with its apparatu 
tions for its use (Phillips's Mineralogy contains brief 
directions), teaches a little mineralogy in a pleasant 
manner. Besides the above instruments, a mountain 
barometer is often very necessary : a portable level would, 
in the case of raised sea-beaches and terraces, be useful. 
Messrs. Adie and Son, of Edinburgh, sell a hand-level, a 
foot in length, which is fitted with a little mirror on a 
hinge, so that the observer, whilst looking along the level, 
can see w^hen the bubble of air is central, and thus in- 
stantly find his level in the surrounding district. This 
is a very valuable instrument. Mr. K. Chambers, more- 
over, and others have found, that an observer having 
previously ascertained the exact height of his eye when 
standing upright, can measure the altitude of any pomt 
w^th surprising accuracy ; he has only to mark by the 
level some recognizable stone or plant, and then to w^alk 
to it, repeat the process, and keep an account how many 
times the levelling has been repeated in ascending to 
the point, the height of which he wishes to ascertain. 

A few cautions may be here inserted on the method 
of collecting. Every single specimen ought to be num- 
bered with a printed number (those which can be read 
upside down having a stop after them) and a book kept 
exclusively for their entry. As the value of many speci- 
mens entirely depends on the stratum or locality whence 



1 



1 

I 



162 



GEOLOGY, 



[Sect. VI. 



they were procured being known, it is highly necessary 
that every specimen should be ticketed on the same day 
wheii collected. If this be not done, in after years the col- 
lector will never feel an absolute certainty that his tickets 
and references are correct. It is very troublesome tick- 
eting every separate fossil from the same stratum, yet it 
is particularly desirable that this should be done ; for 
when the species are subsequently compared by natu- 
ralists, mistakes are extremely liable to occur ; and it 
should always be borne in mind, that misplaced fo3;:rils 
are far w^orse than none at all. Pill-boxes are \ory 
useful for packing fossils. Masses of clay or any soft 
rock may be brought 

abundant in them. Rock-specimens should be about two 
or three inches square, and half an inch thick; they 
should be folded up in paper. To save subsequent 
trouble, it will be found convenient to pack up and mark 
outside, sets of specimens from different localities. These 



details may appear trifling ; but few are aware of the 



home, if small fossil shells are 



labour of opening and arranging a large collection, and 
such have seldom been brought home without some errors 
and confusion having crept in. 

To a person not familiar with geological inquiry, on 
first landing on a new coast, probably the simplest way 
of setting to work, is for him to imagine a great trench 
cut across the country in a straight line, and that he has 
to describe the position (that is, the angle of the dip and 
direction) and nature of the different strata or masses of 
rock on either side. As, however, he has not this trench 
or section, he must observe the dip and nature of the rocks 
on the surface, and take advantage of every river-bank or 



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Stct. VI.] 



GEOLOGY. 



16; 




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4 



J quarry or 



cliff where the land is broken, and o^" 



well, always carrying the bv-is and raa^-es in his mind 






eye to liis imaginary section. In every case this section 
ought to be laid down on paper, in as nearly as possible 
the real proportional scale, copious notes should be made, 



and a large suite of specimens collected for his own 
future examination. The value of sections, with their 
horizontal and vertical scales true to nature, cannot be 
exaggerated, and their importance has only lately bef^n 
appreciated to the full extent. The habit of making 
even in the rudest manner sectional diagrams is of great 



it often 



importance, and ought never to be omitted : 

shows the observer palpably and before it is too late > a 

grief to which every sea-voyager is particularly liable), 



where his knowledge is defective. Partly for the same 



XT 
V 



reason, and partly from never knowing, when first exa- 
mining a district, what points will turn out the most 
important, he ought to acquire the habit of writing very 
copious notes, not all for publication, but as a ^uide for 
himself. He on 




'' Reading maketh a full man, conference a ready man, 
and writing an exact 7nan ;" and no follower of science has 
greater need of taking precautions to attain ..ccuracy; for 
the imagination is apt to run riot when dealing with masses 
of vast dimensions and with time during almost infimty. 



After the observer has made a few traverses of th 






country and drawn his sections (and the coast-c lifts often 
aftbrd him an invaluabl 



\ 



e one). 



he will be himself asto- 
nished how, in the most troubled country, over which the 
surface has been broken up and re-cemented, almost like 



the fragments of ice on a great river, how all the parts 



\ 



E 

! 



"■"_>- 





I 




-"— _^-J 



164 



GEOLOGY, 



[Sect. VI 



fall into intelligible order. He will in Ills mind see tl^e 
beds first horizontally stretched out one over the other in 
a fixed order, and he v.^ill then perceive that all the dis- 
turbance has ariseii from a few nearly straight cracks, on 
the edges of which the beds have been upturned, and 
between which he will sometimes find great \w does of 
once heat-softened, but now crystalline rocks. He will 
find that large masses of strata have been removed and 
denuded, that is ground down into pebbles and mud, and 
long ago drifted away to form in some other area newer 

will now have a good idea of the ph^, Ji ^ 
structure of his district ; and this much can be acquired 
with much greater facility than he will at first readily 



strata. He 



1 



anticipate. 

In examining a district to make a section, many minor 
points of detail will occur for observation, which can 
hardly be specified ; such as the nature and cause of the 
transitions and alterations of the different strata, the 



n . -^ 



source ot tne sediment and pebbles, the alterations in 
chemical nature, either of the whole mass, or of parts, as 
oncretions : the presence, and gi'ouping and state of 



^n c 



..? 



the fossil remains ; the depth and condition of the old 
sea-bottom, when the beds were deposited, and an in- 
finity of similar points. Probably the best method of 
obtaining this power of observation, is to acquire the 
habit of always seeking an explanation of every geologic^al 
point met with ; for one mental query leads on to an- 
otl- r\ and this will at the saiuw time give interest to his 
researches, and will lead him to compare what is before 
his eyes, with all that he has read of or seen. With his 
increasing knowledge he will daily find his powers of 






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cult 

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the 



sec 



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of 

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a) or 



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or£f 



mei 



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Sect. VI .] 



GEOLOGY. 






observation, liis very vision, "become deeper and clearer. 



however, must expect to solve the manj 



^ di 




s 



wliich will be encountered, and which foi 






I Ion 




No 01 

cultie 

time will remain to perplex geologists ; but a ray of 

light will occasionaHy be his reward, and the reward is 



ample. 



diagram 



-! • 1 



w^ 



e 



pposed 



simple superposition 






the beds gives 



. r^.r^^ their relative antiquity : but the be 



section w 



hich 



a 



sea-voyager can hope to make 



will 



seldom include but a small portion of the lor^ ■^'^quence 
of known geological formations. And as the voyager 



seldom passes over large districts, he will rarely succeed 
in plachig in proper order, by the aid of superposition 
alone, the formations which he successively meets with 
even in the same country. Hence he m.ust, more than any 
other geologist, rely on the characters of the 
organic remains, and must sedulously collect every 





men and fragment of a specimen. By the means of fossil 



..mains, not only will he be enabled to arrange (with 
the help of naturalists on his return home) the formations 
in the same country according to their age, but their 
contemporaneity with the deposits of the most distant 
parts of the world can thus and by no other method be 
ascertained ; for it is now known that at each geologica 
epoch the marine animals partook in the most distant 
quarters of a general similarity, even when none of the 



species were identically the same : thus beds have been 



recogni 



and in India 

which must have been deposited when the chalk in Eu- 
rope was accumulating beneath the sea. 



fc-r 



L / 



Lf 



\ , 



^ 
^ 



r 



166 



GEOLOGY. 



[Sect. VI. 



It is liighly necessary most carefully to keep the fossils 
found in different strata separate ; it will often occur iu 



i 



passing upwards from one bed to another, and occasion- 
ally even without any great change in the character of 
the rockj that the fossils will be wholly different ; and if 
such distinct sets of fossils are mingled together, as if 
found together J undoubtedly it would have been better 
for the progress of science that they had never been 
collected. As there is some inconvenience in keepino* 
the fossils collected on the same day separate, this caution 
is the more requisite. The collector, if he be not an 
experienced naturalist, should be very cautious in reject- 
ing specimens, from thinking them the same with what 
he has already got ; for it requires years of practice to 
perceive at once the small, but constant, distinction 
which often separate species: the same species, moreover, 
if collected in different localities, or in bt ' ; one placed 
far above the other, are generally more valuable to the 
geologist than new species. 

In formations from a few hundred to a thousand feet 
and upwards in thickness, the whole of which doe 



s 



3 



actually belong to the same geological age, and is there- 



fore characterized by the same fossils, most curious and 
important resiiUs may be sometimes deduced, if the posi- 
tion or relative heights at which the groups of fossils are 
embedded be noted ; and this is a point usually neglected. 
For, thanks to the researches of Professor E. Forbes, the 
depth of water under which a collection of shells lived 
can now be approximately told ; and thus the movement 



of the crust of the earth, whilst the strata 



iucluding Lie 



shells were accumulating, can be inferred. For iiustance, 



f 



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i^. 










f the sei 



of th^ 



tic" 
raised' 



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desire ^' 
most II--' 

♦' . the 

tai^es ail' 



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are 



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K A4 Ld 



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tb 



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Sect. VI.] 



GEOLOGY. 



167 



I 



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1 



If at the bottom of a cliff, say 800 feet in height, a set of 
shells are burled, which must have lived under water 
only 50 or 100 feet in depth ; it is clear that the bottom 
of the sea must have sunk to have allowed of the deposi- 
tion of the 700 feet of superincumbent submarine strata x 
subsequently the whole 800 feet must have been up- 
raised. For this same purpose, and for other ends, it is 
desirable that it should be noted which species are the 
most numerous, and whether layers are composed exclu- 
sively of single kinds. It should be also remarked, whe- 

bivalve shells retain their two 
valves united, and whether the burrowing kinds are em- 
bedded in their natural positions, as these facts show that 
the shells have not been drifted from afar. Where there 
are fossil corals, it should be observed v/liether the 
greater number of specimens are ujjright, in the positions 



in which they grew. The remark formerly made that 






ther 



ilicate 



the collection of mere fragments of rock is of little or no 
use to geology, is far fi-om applicable to fossil reniaii.^. 
Every single fossil species, bones, shells, Crustacea^ 
corals, impressions of leaves, petrified w^ood, &c., should 



be collected, and it is scarcely possible to collect too 
many specimens. Even a single species without any i r 
formation of any kind, if it prove a quite ne'w form, will 
be valuable to the zoologist; if it prove identical with, or 
closely allied to a known species, it may interest the 
geologist. A set of fossils, however, and still more 
veral set?., with their superposition known, cannot fail 
^" of the highest value ; they wdll tell the age of the 
deposit, and perhaps give the key to the whole geology 
of the country: some of the highest problems in thi 



r\rA 



to 



iS 




JB^ 



i 

i 
1 



168 



GEOLOGY. 



[Sect VI. 



The collecting 



science wait for solution on large collections of species 
carefully made in distant regions. 

A collection of recent shells (both those living on 
the coast and those to be procured by the dredge oft 
it) from the same country or island at which a coUec- 
tion of tertiary fossil shells is made, is generally of 
very great service to the palaeontologist, who under- 
takes the description of the fossils, 
recent shells will, moreover, with the aid of a little 
study, teach the geologist some conchology, and this is 
an acquirement yearly becoming more necessary : the 

eologlst should exert himself to learn some general 
zoology. 

The bones of vertebrated animals are much more 

rarely found than the remains of the lower marine anl- 

mals, and they are almost in proportion more vjiluable. 

A person not acquainted with the science will hardly be 

able to imagine the deep interest which the discovery 

of a skeleton, if of higher organization than a fish, in 

any of the oldest formations would most justly create. 

The age of such a formation would have to be judged 

of by the co-embedded shells, and therefore, if possible, 

part of the slab containing the bones should include 




one or two shells to demonstrate their contempo^a 



neity. Bones, however, from any formation are sure 
to be valuable ; even a single tooth, in the hands of a 
Cuvicr or Owen, will unfold a whole history; the h'vds, 
jaws, and articular surfaces are the most valuable : but 



every fragment should be brought home. 



Where bones 



are found close together, and especially if some cf the 
parts lie in their natural positions, they should be packed 



Sect' 



vM 



tlie 



itber- 



b! 



1 



call 



i;*' 



1 



!)■ ^-^ 



.neg 



to 



still li 
clay on t' 
as in ba^' 

p.. 
Gravel ' 

rocls; P' 

are all • 

oiaally i 



f. 



hrsrf 



rocks, an 






' fi 



re 



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oi 



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Sect. VI.] 



GEOLOGY. 



169 



k 



(»^ 



\ v' 



I). 



h 



I 






'-. 



w -^ 



»v 



/I 







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wvma 






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TH 







L 



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b 



IC 



u;r' 



TT>-^ 



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U " 



together. Every bone, if found even six inches beneath 
the black vegetable mould, should be collected : there 
can be no doubt that many most valuable relics have 
been neglected, from the supposition that they belonged 
to still living animals. Low cliffs of mud. 




ravel, and 
3S (as well 



fc 



"- =r _-. 



lYom them), are the most likelv 
places for the discovery of the remains of quadrupeds. 
Gravel beds under streams of lava ; fissures in volcanic 
rocks ; peat beds, and the clay or marl underlying' neat, 
are all favourable places. Fishes' bones are found occa- 
sionally in all sedimentary strata, and are highly inte- 
resting. 

Caverns. — These most frequently occur in limestone 
rocks, and they have yielded a truly wonderful harvest of 
remains in Europe, South America, and Australia. The 
bor generally occur in mud, under a stalagmi tic crust 
produced by the drinp:..g of the lirae-charsed water. 



i' 




a 



wiuch requires being broken up by a pickaxe. As ca- 
,v..n3 have often been used by wnld races of man as 
places of habitation and burial, a most careful examina- 
tion ^^ ould be made to detect 
havi' ■ 



gns 




: been anciently broken up near where the bones 
are found. Even small islands, not now inhabited by 
any land quadruped, if not very distant from a continent, 
are almost as likely to contain osseous remains as larger 
tract-^ of land. The interest of the discovery of the re- 
mr'ns of land quadrupeds in an oceanic island would be 
extreme : for instance, it has been stated that the tooth 
of a mastodon has been found in one of the Azores ; if 
tius were confirmed, few geologists would doubt that 



I 



- .>-^"--f^ 






^ 






t 



-^ -.*^ 



170 



€ EOLOG Y- 



[Sect. VI. 



these islands had once been united to Europe, thus en- 
larging wonderfully our ideas of the ancient geography 



of the Atlantic : so also the remains of a mastodon are 
said to hare been brought from Timor, thus perhaps 
indicating the road by which this great quadruned 



formerly reached Australia. 



Fossil Footstep 
footsteps may be 



As allied to organic remains, fossil 
here referred to. They have been 
observed in Euro}>e and North America, but hitherto in 
no other part of the world. These curious vestiges not 
only proclaim the former existence of reptiles and birds 
at very remote periods, and in rocks often not containing 
a fragment of bone, but they generally prove that the 
level of the land subsided after the animal had left its 



impress on the ancient sea-beach, thus allowing thousands 
of feet of strata to be thrown down over them. The 
best place for searching for footsteps is in quarries of 
sandstone^ in which the strata are separated by seams of 



shale. The best indicati 



jn of their probable occurrence 
is the rock being ^^ rippled,'' that is marked with narrow 
little wavy ridges, such as occur on most sandy shores 



when 



the tide 



is down, and wliich indicate that tlie now 



--■^ 



rocky surface w^as once either a tidal beach or a shall 
surface, over ¥/hich the ancient animals w^alked. In the 
case of fossil footsteps being found, the largest slab 
which could possibly be removed ought to be br aight 
away, and accurate drawings, or still better, casts, mad^ 
of several of the footsteps. A plan from accurate mea- 
surement ought to be taken of any row of steps. The 
value of such fossil footsteps would be in a manifold 
degree increa^-^d, if the age of the deposit cor^'^ be 



r 

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Sect. VI.] 



GEOLOGY. 



171 



f 



a 



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Im. 



lll?v_ 



1- 




V. 



mi 



t 



1 



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rb 



lU 




lb.- 



determined by shells found in the ^^*^me stratum, or 

above it. 

Coal Deposits. — The origin of coal presents a most 

curious and difficult problem in geology, and tliough a 



vast amount of information has been accumulated on the 
subject, yet good observations in distant countries would 
be of the highest value. A very brief statement of the 
most prominent difficulties in the theory of its origin will, 
perhaps, be the best guide for further inquiries. If we 
look first to the coal itself, the frequency with which, 
both in Europe and North America, upright vegetables 
have been found in and on the coal, and the curious rela- 
tion between the presence of coal and the nature of the 
clayey bed (abounding with roots) on w^hich it rests, can 
leave no doubt that in these so frequent instances the 
vegetation, whence the coal has been derived, grew on 
the spot where now embedded. The regularity and 



wide extent of the beds of coal, and especially of certain 

subordinate seams in them, the stratification and fineness 

of the deposits alternating with the coal, aiid the rarity 

of channels (such as would have been formed by a 

^ through the associated strata, 
all 



') 




seem pretty clearly to indicate that the coal wa.^ 
not formed on the surface, like a mass of peat, but 
under water. AVhat, then, was the nature of those 



vast 




of shallow water under which the coal 



was accumulated ? The character of the upright fossil 
plants, according to our present knowledge, absolutely 
contradicts the idea of their having lived in the sea; 
yet occ'-'-ionally strata, 

remains, are r.sociated with the carboniferous series. 



containing undoubted manne 



* 



-.* 



i2 



I 



i 

f 

1 



1 




:S — "V ? :^ '^- 



^^ — 



172 



/^ 



EOLOGY. 



[Sect. VL 



S 



i^^ci 



On the other hand, how can we believe that lakes, allow- 
ing of course their beds slowly to pink, could contain the 
enormous thickness^ amounting in some instances to 



s 



t 



m 



;pot, or 



several thousand yards, of the coal-bearing strata ? i: oiu 
these few remarks it will be seen how many points de- 
serve careful examination in any nevr coal district ; the 
chief points being, the presence of upright vegetables and 
trunks of trees (of the position of which careful drawing 
should be made), and whether furnished with roots,~the 
nature of the beds on which the coal rests, and generally 
of all the strata ; the continuousness and form of the 
strata, and whether ripple-marked ; the existence of 
marine animal remains, and whether such lived on the 

^ 

were drifted into their present posiUuns, and 
many other similar points. It is superfluous to observe 
that all fossil plants should be collected ; those found 
upright should be carefully distinguished from those em- 
bedded horizontally. The contents of any upright stems 
and of the roots should be examined ; as it appears they 
have generally first become hollow from decay^ and then 
been filled up v/ith mud, which in some instances is 
charged with seeds and leaves. 

Salt Deposits -—luiormdition is much required on this 
subject ; and tins is a case in which good suites of speci- 
mens, illustrating the nature of the rocks beneath and 



above the salt, would possess much interest. Do they 
rontaiii any organic remains? Did such live on tl^ spot 
where now buried ? Do the rocks show sisrns of having 



undergone in any degree the action of heat ? Are the 
strata regular, or are they crossed by obhque layers, 
rfiov/ing the probable action of currents ? Are tLv.re ripple- 



[ 



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IS 



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dill 

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link 



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1. 






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Do. 



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bottl 



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perp] 
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origij 

obli- 

coast 

till, i 






I 



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Sect VI.] 



GEOLOGY. 




s 






i 

\ 

4 

S 



marks, or beds of coarse pebbles, or otber indications of 
the strata having been deposited iu shallow water ? What 
is the tliickness, form, and dimensions of the beds of salt ? 




H-iimens of the salt, and of any associated saline sub- 
stances, ought to be brought home in bottles for analysis. 
The oriffin of beds of salt, found in formations of very 
different ages in different parts of the world, is at present 
quite obscure ; some authors attribute it to the sinking of 
superficial sea-water, rendered more saline by evaporation , 
others to the evaporation of sea- water periodically over- 
flowing extensive low sandy tracts, like parts of the Run 



of Cutch ; others suspect that its deposition is in some 
unknown way connected with the sea's bottom having 
been heated by volcanic action. In some countries there 
are large lakes of brine, often covering thick beds of salt ; 
these deserve examination: on what does such salt or 
brine rest, whether on the bared underlying strata, or on 
«and or gravel, such as cover the surrounding country ? 
Does the salt contain the remains of animals or plants ? 
Specimens of the salt ought to be brought 
bottles, and attention paid, whether beneath it there is 
any thin layer of other saline substances. 

aeava(/e.--T\ie slaty structure of rocks will at first 
perplex the young geologist ; for in proportion as it be 



Si-^-i^ 



>^1 







m 



r- 



comes well developed, the planes of stratification or of 
original deposition become obscnre, and are often quite 
obliterated. As the sea-voyager, and especially the sur- 
veyor, often visits numerous points on the same line of 
coast, he possesses some great advantages for studying 
this subject, and numerous observations made with care 




I 






174 



GEOLOG!f. 



[Sect. VI 



would probably give striking results. The range or strike 



of the cleavage is uniform over surprisingly large areas ; 
whereas botli the angle and point of dip varies much • 
but there is reason to believe that the planes of inclination, 
examined across a wide tract transversely to the ranoe, will 



fall into order and show that thev are the truncat^-d edo-es 
of ■ 



( 



a tew great curves or domes. The relation of the 
•leavage-planes to those of the stratification, or axes of 
elevation, should be carefully noted, and likewise to the 
general outline of the whole country. Long sections at 
right angles to the strike of the cleavage, with the dip 
oarefully protracted on paper, would be highly interest- 
ing. When two chains of hills, each having its inde- 
pendent cleavage, cross each other, careful observation., 
should be made. In all cases, any mineralogical differ- 



ence 



however slight, in the parallel cleavage-layers, 
deserves attention ; but observations on this head would 
be hardly trustworthy, without the planes of stratification 
were so distinct that there could be no possibility of con- 
founding (as has often happened) cleavage and stratifica- 
tion. Where a stratum of sandstone, or of any other 
rock without cleavage, is interstratified with a slaty rock 
the siu-fece of junction ought to be minutely examined, to 
see if the slate has slipped along the planes of cleavage 
..r whether again the mass has not been either stretched 



> 



> 



-J 

or compressed at right angles to these same planes. 



Fossil shells hav^e been 



Mr 



rocks, wliich have had their shapes greatly a'^ered, and 
all in the same direction ; here then we have a guide to 
judge of the amount and direction of the mechanical 



i 

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(iisp 



on 
iiii 

th( 



•( 



P^ 



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act] 



re 
but 



the 



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vein 



are 



^■ar 



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the 
not: 

strat 



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Sect. vL] 



GEOLOGY. 



175 



_ * 



4- 




t * 



4 



^^ 



K* 



^4 



pr^- 



* _ 



I 



*^ 



displacement which the surroundin 




"late-rocks have 



undergone/' 



Observations on cleavage, to be useful. 



must be numerous and very accurately made. 



T 



he foliation of the metamorphic schists, that is, tr.e 
origin of the layers of quartz, mica, feldspar, and other 
minerals, of which gneiss, micaceous, chloritic, and horn- 
blendic schists are composed, is intimately connected with 
the cleavage of homogeneous slaty rocks. Nearly all the 
proposed observations on cleavage are applicable to folia- 



!-' 



tion. Wherever large districts of foliated and ordinary 
slaty rocks unite, observations would be most desirable. 
These foliated rocks have all undergone metamorphic 
action, that is, they have been mineralogicHliy altered and 
rendered crystalline by chemical attraction, aided by heat ; 
but this is a most obscure suliject, one on which it would 
appear that much further light will not be thrown without 
the aid of a profound knowledge of mineralogy or che- 
mistry. It is now known that granitic rocks, which have 
been fluidified (as may be told by their sending great 
veins into, and including fragments of, the overlying rocks), 



4- 






are foliated in a more or less perfect degree: in these 
cases the relation of the planes of foliation with those of 
the adjoining rocks, which have been metamorphosed but 

not fluidified, would be eminently curious. 

the Sea-bottom. — As every sedimentary 



Nature of 



stratum has once existed as the bed of the sea or of a lake, 
the importance of observations on this head is obvious ; 

* With respect to further observations on this important point, Mr. 
Hopkins remarks, in his paper ' On the Internal Pressure of Sock 
Masses ' (Cambridge Philosoph. Transact., vol. viii.), that " the observer 
should direct his attention especially to those cases in which the inclina- 
tion of the cleavage planes to the bedding is either small, or nearly 4.5-." 



■^ -f 



I 



■^- ti- ^r^ 



, -t^^^^t^j-flC^-^ -^ 



176 



GEOLOGY. 



[S€^t. VI. 



i 



0^- 



i 



I 






and no one is so favonrably circumstanced for making 



ft 



them as a naval officer on a survcyiiig expedition. The 
limits of depth under different latitudes at wliich the 
variuas marine animals live or are found strewed dead, is 
perhaps the must important point for further investigation 
which can be suggested in the science of geology : scarcely 
any observations with the dredge have been made witliin 
the 



tropics. Not only the shells, corals, sea-urchins, 



crabs 



&c. 



9 



brought 



s, 



up from different stated depth 
siiould be pi^eserved, but the proportionate numbers of 
each kind be carefully noted, as well as the nature of 
the sea-bottom. An observer could not labour too much 
in this line, and especially if he would subsequently him- 
self undertake to tabulate and work out the results,* 

There is another point of view under which the bed of 
the sea v/ould amply repay long-continued observations. 
t is well known that the nature of the bottom often 



changes very regularly in approaching a 



ly\> «^^ .-^V m 



th 



e 



pebbles, for instance, increasing in size in a surprisingly 
steady ratio with the decreasing depth. But the means by 



which the pebbles are thus sorted is not known : is it by 
the oscillation of the waves at ordinary periods, or only 
during gales ; or is it by the action of currents ? A chart, 
with the l]^'ture of the bottom carefully noted on it and 
the currents laid down, would by itself throw some lidit on 
tms question. The nature of the pebbles being observed, 
perhaps a point would be found whence they radiated. 
xccllent observations have been made by engineers on 
the travelling of shingle beaches, but scarcely anything is 




* The best kind of dredge, and the manner of using it, are described 
under the Zoological Section. 



L 



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dit 

lia 



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iia 



iVi 



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1110 

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up 

pov 
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aiid 

Plej 
of, 



■^tt«= 



1' p 



Sect. VLj 



GEOLOGY 



177 



known of their movement under water. In what con- 
dition are the pebbles '^—are they encrusted (as often 
happens) with delicate corallines — after a heavy gale are 
the spines of such corallines found broken? In narrow 
channels where there are rapid currents, and in the open 
sea in front of straits, where the water often suddenly 
deepens, what is the nature of the bottom ? To what 
depth does the sea in a storm render the water muddy ? 

far from the beach, and to what depth, does the 



How 



recoil of the waves, or the 



" undertow," act, for 



m- 



stance, on light anchors ? At what depth can the sea wear 
solid rock ? This may sometimes be judged of by the 
nature of the bottom ; thus, where soft mud overlies the 
rocky surface, we may infer that the sea can hardly now be 
a destroying agent, even if the inclination of the strata 
on the adjoining coast shows that rocky strata must once 
(probably, w^hen the land stood at a different level) have 
extended much further. Is it at the line of hio'h or 



low water, or between them, that the breakers most 
vigorously eat into coast-cliffs ? Gigantic fragments of 
rock, much too large to be themselves rolled about, 
may be seen at the foot of almost every line of high cliffs ; 

by what means in the course of time will these be re- 
moved, as must have happened v/ith their innumerable 
predecessors? Are they slowly worn away or broken 
up? It may be well to recollect tliat in the tropics the 
powerful action of frost in splitting stones is entirely 
eliminated. Our observations, moreover, on the alluvial 
and sub-littoral deposits of these latitudes are not per- 
plexed by the ancient eli^cts of floating ice. The spray 
of salt-water, above the line of breakers, corrodes by 



-» 



I. 



I 3 



f 

! 

! 

t 
J 

I 

! 




tF. 



i 



'^ 



4 

i 



178 



GEOLOGY. 



[Sect. VI. 



chemical decomposition calcareous rocks; does tliis play 
any important part on other rocks ? Most bold coasts 
are fronted by sharp promontories and even isolated 



pmnacies } 



arc 



these excl :ively due to tlie greater hard 



i: -ss of the rocks composing them, or do not the breakers 
act more efficiently when 



t T • 



round 



eaaymg rouna any ^..^ 



slight 



projection r 

Rocks rising steeply out of the open ocean, and cx- 

poo^id to the incessant wash of the heaviest surf, are often 

thicMy coated over with various marine animals, and 

this w^ould seem to indicate that pure water has not the 

power of gradually wearing av/ay hard rocks, though the 

waves may occasionally tear oiF large fragments. Is the 

washing to and fro of pebbles, or of sand, a necessary 

element in the corroJhig power of waves on hard rocks ? 

but how comes it that small land-locked harbours, where 

the waves can hardly have force to move the shingle, 

should ever be surraunded by cliffs, which, in most 

cases, clearly prove that considerable masses of rock 

have been vy-orn down into mud and removed ? Again, 






covered 



shingle^ does the rolling to and fro of the pebbles wear 
away solid rock ? if so, the pebbles would be clean, and 
the submarine rocky surface probably w^orn into farrows 



or channels at right andes to the beach. Where there 



are violent currents and eddies, are deep round holes 
worn in the bottom, like those produced by eddies at the 
foot of cascades? This, perhaps, might bo ascortaiiied 

polo at the turn of the tide : deep round 



bv a lonpr 



holes have been observed on rocks formerly eo-v 



'cred 



by tl 



1143 sea, and their 



ormm 



h 



■i ■> 



perplexed geologists. 



p 



/ 



se- 



*f 



An 

sh 
of 



A 



y J 



m 



^v 



la 



d- 



3 



or 

X, - 



li 



irr 



OY 



S" 



be 



ffi] 



rei 



t^ 



. * ^ 



pO] 

fo 



r 



m 



ft 



or 



t/ 



Uj 



r 



/\ 



<f'. 



hw 



« i 



t 



Sect. VL] 



GEOLOGY. 



179 



will 



Any person st: ^Jly atteiidiiig to tbese subjects 
occasionally be enabled to form an opinion on poin 
at first appearing hopelessly obscure to bim. 



ts 



Tbo com 



mon 



deep-sea lead, especially if made a little bell- 
shaped and well armed, gives a surprisingly good picture 
of the bottom. There can be no doubt that whoever 
will for a long period collect and compare observations, 
made over wide area& and under different circumstances, 
will arrive at many curious, novel, and important results. 
An observer occasionally may arrive at a district where 
lately some great aqueous catastrophe has occurred, such 
as the bursting of a lake temporarily formed by a slip, 



or the rush of a great 





1 



■'-\ 



-wave over low land. 



cases 



ness and nature of any deposit left— whether stratified 
irregularly or continuously— whether any rocky surface, 
over which the debacle has passed, be scored or smooth ; 



, and mea- 



all such points should be minutely described 
suroments taken of any great blocks which may have 



been transported : the great desideratum is accuracy and 



minuteuuci. 



Ice Action. — The vovager in 



the Polar 




would 



render an excellent service to geology by observing all 



the effects which icebergs produce in rounuing, polishin 



g^ 



g solid rocks 



porting gravel and boulders. Fluatln 




ice under two 



rments 



I 



in whi-^^ the stranded boulders are frozen, and icebergs 
formed by gbciers entering the sea^ on the surface of 
v.hich masses of rock had previously fallen from the wur- 
rounding precipices. It is obvious that in the latter case 



i 



i 




I 





.5 



r- J 



180 



GEOLOGY. 



rSeci. VI. 



the fragments would generally be qnito angular, and 
they could not be landed in water shallower than the 
thickness of the submerged ice, requisite to float the 

On the other hand, the boulders frozen in coast- 

and they 



ber 




ice would 




om 



could be landed on an ordinary beach, and might be 
driven by the force of the pack high and dry, and perha,ps 
left pilcJ in strange positions. All facts illustrating the 
difference in the results produced by coast-ice and true 
icebergs would be very valuable. Do the boulders fixed 
on coast-ice, when driven over rocky shoals, become them- 
selves scored? Wherever there was reason to beli.,e 
that a surface had been scored by recent ice-action, a 
minute description and drawings ought to be made of the 
depth, length, width, and direction of the grooves ; and 



even large slabs brought home. On true iceberf^ 



when 



the fragments of rock generally fixed or lou^c^ 
icebergs turn over, are fragments frequently seen em- 
bedded in thuE part which was under water ; and how were 



thcv 



fixed there : 



The nature, number, si^^e, form, and 
frequency of occurrence of all fragments of rock seen on 
floating ice ought to be recorded, and the distance from 



their probable source. A 



raised 



5 



known from up 



orsaniG 



remains to have been latelv elevated 



would be eminently instructive. 



Do 




reat icebergs 



force up the mud and gravel at the bottom of the ^^a 

glaciers ? Can shells, 



in a shallow sea, often 



in ridges like the moraines of 

or other marine animals, live 

ploughed up and rendered turbid by the stranding of 

icebergs ? The dredge alone could answer this, i he 

means to distinguish the effects of ancient floating ice 



V 



( 



i. 



V, 



flOl 



.,^1 



tL 






1 



m 



'^{ 



in 
act 
Ian 



^-"«V. 



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as 



all 



SiZi 



4: 

4 



cou 

isol 



a. 






*,■- , 



ove 



it 



I'*'' 



'\ 



k 



V 



Sect. YL] 



GEOLOGY. 



181 



from those produced by ancient glaciers is, at present, 
reat desideratum in geology. M. Agassis' work on 




Glaciers, with its admirable plates, ought to be procured 
by any one going to the colder regions of the north or 

south. 

Erratic boulders occur in Europe, N, America, and in 

the southern parts of S. America, which, it is believed by 

most geologists, were transported by ice ; those near 

mountains, by ancient glaciers ; and those on the low- 



lands, by floating ice. 



Erratic 



boulders, when not of 



gigantic size, may be confounded with rounded stones, 




tne coast- 



transported by occasional great floods or 

action of the surf during slow changes of level of the 

land. Masses of granite, from often disintegrating into 




large, apparently water-worn boulders, and then rollin 
downw^ards, have several times been erroneously described 
as belonging to the erratic class. Where the nature of 
all the rocks in the vicinity is not perfectly known, great 
size and the angularity of the fragments (though by no 
means a constant concomitant) are the most obvious dis- 
tinctive characters; but even wdien the surrounding 
country is not at all known, the composition of a single 
isolated hill or small island may easily be ascertained, 
and if large fragments of foreign rock lie strewed on its 
surface, these may be assumed almost certainly to be 
erratic boulders. Here, how'cver, a caution has been 
found necessai y ; for in the case of fragments of sedirneu- 
tari/ rocks, they may be the last remnant of a denuded 
overlying formation. Wherever erratic boulders are 
found, their composition, form — especially attending to 
whether they are angular, water- worn, or scored, an<i 



\ 



J- ..f 



182 



GEOLOuV. 



[Sect. VI. 



the5 



eir size, from p-^-'iial though rude measurements, should 



be given. 



Both in the north and south a peculiar formation called 
'' till '' has boon found connected with erratic boulders ; 
it consists generally of mud, containing angular and 
rounded stones of all sizes up to the largest boulders, 
mingled in utter confusion, and generally without any 
stratification. Such deposits should be examined. Some- 
times when they are stratified, the upper beds have been 

r 

found violeniiv contorted, whilst the lower ones are un- 
disturbed, showing that the violence has not procc^^J^d 
from below, as in ordinary geological cases. Sir C. Lyell 



has suggested that this effect has been produced by the 
stranding of great icebergs. 

As far as our present knowledge goes, the abovo enu- 



merated phenomena — such a.^ scored, mamillated, and 
pollahed rocks, moraines, erratic boulders, and beds of 
^ Lough occurring in latitudes where glaciers do not 
now occur, w^here the sea is never frozen, and where 
icebergs are never drifted, yet have not been observed in 






5 



dther hemisphere higher than about latitude 40^, Hence 
on whatever coast ancient ice-action might be discovered, 
the limit of latitude towards the tropics at which it ceases 



ought to be carefully investierated. Observations are 




much waritcd on the west coa-ist of N. America and the 
east coast of Asia ; and again in New Zea^land and other 
islands of the Southern Ocean. The period of the ice 
action is pretty ,. Jl ascertained in Europe and North 
America, and a very great service would be rendered to 
geology if the same point could be clearly made out in 



the southern hemisphere ; for it might greatly influence our 



I 



idea 

< 

we 



tb 



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orj 



1 






wr, 



op] 

air 

of' 

be 




thf 



diK 



Ar 



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u 



obi 

V 

floa 
are 

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trai 



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or 

ran 






01 



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/* 



^ .-. > 



VI.] 



GEOLOGY 






ideas on the cliniate of the world during the late tertiary 
periods. Any shells embedded in '' till " (though, unfortu- 
nately, of very rare occurrence) would decide this point, and 
it might probably be closely iudged of, if till or boulders 
^vere found resting on, or covered by, shell deposits. 

As geology includes 



n 



a oj 



Be 



the history of the organic inhabitants, as well as of the in- 
organic materials, of the world, facts on distribution come 
under its scope. Earth has been observed on icebergs in 
the open ocean ; portions of such earth ought to be col- 



lected, washed with fresh-water, filtered, gently dried, 



wrapped up in brown })ciper, and sent home by the first 



opportunity to be tried, with due precautions 



whether 



any seeds still alive are included in it. Again, the roots 
of any tree cast up on an island in the open ocean should 
be split open, to see if any earth or stones are included 
(as often happens), and this earth ought to be treated like 
that from icebergs : it is truly surprising how many seeds 
are often contained in extremely small portions of earth. 

Any 

have the contents of its intestines dried for the same 

with a towing-net, fish-3 for 




raminivorous bird, caught far out at sea, ouglit to 



The zoologist who 



object. 

floating unnute animals, ought to observe whether seeds 



■^^, insect 



are thus taken. These experiments, though troublesome, 
undoubtedly, would be well worth trying. All facts or 
traditional statements by the inhabitants of any island or 
coral-reef, on the first arrival of any bird, reptile 
or remarkable plant, ought to be collected. In those 
rare cases in which showers of fish, reptiles, shells, earth, 
seeds, confcrvae, &c., have fallen from the sky, every fact 
should be recorded, and specimens collected. 

Volcanic Phenomena. — The voyager will probably have 



=^\ 






■i 







I 



J. 



I 




V.' . -t- -^ -r .. 






184 



GEOLOGY. 



[Sect. VI. 



ample opportunities of examining volcanic islands, and 
perhaps volcanoes in eruption. With respect to the lat- 
ter, he ought to record all that he sees : should the exact 
position of the orifice be known, he might, perhaps, 
observing some point in a cloud, measure with a sextant 
to what height the fragments were shot forth, and the 
height of the often flat- topped column of ashes. Having 
surveying instruments, he ought to map, as carefully 
as time will permit, any crater remarkable for its size 

Elie de Beaumont has 



depth, 01' peculiar form. M 

found that, owing to the fluidity of lava, streams never 

consolidate into a thick, moderately-compact mass, ex- 



cept on a surprisingly gentle inclination. On 
above 2 or 3"", the stream consists of extremely irregular 
masses, often forming a hollow vault within. Fresh ob- 
servations on this point are much wanted in regard to 
lavas of different composition. The measurements can 
easily be made by a sextant and artificial horizon.* In 

M. Elie de Beaumout gives the foUowiiig directions (Memoires pour 
servir, &c,, torn. iv. p. 173) : 

" The method I arn in the habit of employing for these kinds of mea- 
surements is simple and easy, and a description of it may save useless 
trouble to others. I place on the edge of the sextant, and behind the 
fixed mirror, a small piece of white paper, in which there is a narrow 
opening (ouverture etroite) corresponding to the axis of the telescope. 
On the exterior surface of the paper a black line is drawn, perpersdicular 
to the i>lan of the graduated circle, and passing through the centre of 
the opening above mentioned. A quantity of mercury is poured into a 
vessel sufficient to Ibrm a plane horizontal surface of a certain extent. 
The telescope of the sextant is then directed vertically over the mercury, 
and the image of the black line sought for. When this is found, I am 
certain that the visual raj/ from the image In the mercury can only 
deviate from the perpendicular^ in so far as the line is not without 

i, and the opening has a sensible size. These two sources of error 
can be diminished so that the maximum of error shall not exceed a 



br 



T .-■ 



niinute. Being once certain of the verticality of the visual ray f. 'n the 



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tn^' 



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lO 



vU 



of 

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des 



it 



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siet 
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colli 
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dec 



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Sect. VI.] 



GEOLOGY. 



185 



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making ^^ich observations, comparatively recent streams 
must be chosen, so that there can be no donbt that the 
whole consists of a single stream : this cannot be judged of 
without examining the whole line between the two points 
of measurement, forborne liquid lavas thin out to a very 
fine edge ; and tv/o streams, one over the other, may be 
thus very easily mistaken for a single one. The compo 
sition, thickness, and degree of cellularity of any lava 



stream 



s 



of which the s 



lope is measured, ought to be 



described as seen on the sides of fissures, and wherever 
its internal structure can be made out. 

Round manv active and extinct volcanoes, both on con 
tinents and on islands, there is a circle of mountains. 



steep on their inner, and gently inclined on their outer 




flanks. The volcanic strata, of which they are composed, 
everywhere dip away from the central space, but at a 
considerably higher angrle than it is believed lava can 
consoUdate into such thick and compact masses, 
mountains form the so-called ^^ craters of elevation,'' the 
origin of which has excited much controversy, and which 
demand further examination. There is a grand range of 
mountains of this class at the Mauritius and at St. Jago 
in the Cu.pe de Verdes, parts only of which have been 






described. The chief points to attend to are, th-^ '--''-^ 



e mclina 



tion of the streams by actual measurement, their thick- 
ness, compactness, a.nd composition ; the form and height 
of the mountains, whether traversed by very many dikes, 

image of the black line, 1 have only to make the image of any object 
reflected from the moveable mirror coincide with that of the block line, 
to have the -^^ gle bet^* en the vertical, and the line drawn from the centre 
of the instrument to the object in question, which may be any distant point 
on the surface of a bed of lava, a glacier, a road, a river, occ/' 



\ 



-^-' ,- -:4C«c T-T. 



^ #. __ 



v-- 



f 



186 



GEOLOGY. 



[Sect. VI. 



gec^. 







of which the common direction ought to be recorded • 
how far the mountains stand apart, and the diameter and 
outline of the rude circle which they together form. In 
fact, a most useful service would be rendered by mappino* 
any of these "craters of elevation/' or, what would be 



more feasible, drawing from actual measurements two 
sections at right angles to each other, across the circle. 

Some streams of lava, especially those belonging to the 
trachytic series (harsh, generally rather pale-coloured 
lavas, with crystals of glassy feldspar), are laminated. 
The course of the layers with respect to the course of the 
stream ought to be minutely studied, both on tlie surface, 
at the termination, and flanks of the stream ; and, if by 
a mo^t fortunate chance there should have been formed 
a transverse section, throughout its entire thickness : this 
would be a very interesting subject for investigation. A 
series of specimens ought to be brought away to illustrate 
the nature of the lamination. 

Aerial Dust, — Fine brow^n-coloured dust has often 



fallen on vessels far out at sea, more especially in the 
middle of the Atlantic. This should be collected ; the 
direction and force of the wind (and the course of any 
upper current, as shown by the movement of the clouds) 
on the same day, and for some previous days, ought to 
be recorded, as well as the date, and the position of the 
ship. Such dust has been shown by Ehrenberg to con- 
entirely of the siliceous 
envelopes of infusoria. The distance to which real vol- 



sist, in many cases, almost 



canic dust is blown is, likewise, in some respects well 



worth determining. 

Elevation of the Land. — The changes of level, often 



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the ■ 

sh-i^ 

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from 

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Sect. YI.] 



GEOLOGY, 



Q?7 



ibV 






accoTiipanying earthn^uakes, will be treated of by 
Mallet, bat a few remarks on the nature of the evidence 
to be Bought, on change^' of level not actually witnessed 
by man, may be here mserted. Many appearances, such 
as hnes of inland cHffs, of sand-hillocks, eroded rocks, and 
banks of shingle, often indicate the former effects of the 
sea on the land when the latter stood at a lower leveL 
But the best evidence, and the only kind by which the 
period can be ascertained (for the appearances above 
enumerated, though well preserved, may sometimes be of 
considerable antiquity), is the presence of upraised recent 
marine remains. On land which has been elevated within 
a geologically recent time, sea shells are often found, 
either embedded in thin layers of sand and mould, or scat 
tered on the bare surface. In these cases, and especially 



in the latter case, great caution is requisite in testing the 



evidence ; for man, birds, and herm^it-crabs often trans- 
port, in the cour >. of agos, an extraordinary number ox 



shells. In the case of man, the shells generally occur in 



heaps, and there is reason to believe that this character is 
long preserved^ To distinguish the shells transported by 
animals from those uplifted by the movement of the earth, 
the following characters may be used ;— Whether the 
shells had long lain dead under water, as indicated by 
barnacles, serpula?, corallines adhering to their insides t 
whether the sheik, either from not being full grown or 
from their kind, are too small for food ; remembcHng that 
certain shells, as mus^ols, nu.^ be unintentionally trans- 



ported 




man or other animals in their young state 



adhering to larger shells ; and lastly, w hether all the spe- 
cimens have the same appearance of antiquity. Some 



^-. 



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GEOLOGY, 



[Sect. VI. 



shells, \ 



,vhicn have hceii exposed for many ages, yet retain 
their colours in a surprising manner. The very hest evi- 



dence is afforded by barnacles and boring shells being 
found attached to or buried in the rock, in the same posi- 
tions in which they had lived ; these may be sometimes 
found by removing the earth or birds' dung covering points 
of rock. Where shells are embedded in a superficial layer 
of soil, though it may appear exactly like vegetable mould, 
specimens of it should be preserved, for the microscope 
will sometimes reveal minute fragments of marine animalg. 
In ail these cases, specimens of the shells, though broken 



to 

and weathered, and having a wretched appearance 



J 



must 



carefully be preserved ; for a mere statement that such 
upraised shells resembled those still living on the beach is 
absolutely of no value. It should be noticed whether the 
proportional numbers between the different kinds appear 
to be nearly the same in the upraised shells and in those 
now cast on the beach. The height at which the marine 
remains occur above the level of the sea should be mea- 
sured. In confined situations where the change of level 
appears to have been small, much caution must be exer- 
cised in receiving any evidence ; as a change in the direc- 
tion of the currents (resulting from alterations in neigli- 



s 



bouring submarine banks) 
omewhat less height, and 
the land having been upraised. 



US 



the appearance of 



\\ herever a tract of country can be proved to have 
been recently elevated, its surface, as exhibiting the late 
action of the sea, is a fertile field for observation. On 



«ncl 



1 coasts, terraces rising like steps, one above another 



often occur. Their outline and composition should 



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Sect, VI.] 



GEOLOGY. 



189 



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3.. 









ttudied, diagrams made of tliem, and their height m.ea- 
sured at manv and distant parts of the coast. There is 
reason to believe that in some instances such terraces 
ran^e for surprisingly long distances at the same height. 



Where several occur on opposite sides )f a vallev a spirit 



^. 



level is almost indispensable, in order to recogni' 



the 



corresponding stages. Where ranges of cliffs exist, the 
marks of the erosion of the waves may sometimes be ex- 
pected to occur, and as these generally present a defined 



^ "^ CJ 



line, it is particularly desirable that their horizoiitality 
should be ascertained by good levelling instruments, and 
if not horizontal, that their inclination should be mea- 
sured. Where more than one zone of erosion can be 
detected all should be levelled, for it does not necessarily 
follow that the several lines are parallel. Along extensive 
coasts, and round islands which have been uplifted to a 
considerable height, and w^here w^e now walk over what 
was, within a late geological period, the bed of the 
it would be well to observe whether extensive sedimentary 
deposits have been upraised ; for it has often been tacitly 
assumed that sedimentary deposits are in process of form" 

ation on all coasts. 

Subsidence of the Land.-'-Tlns movement is more dif- 
ficult to detect than elevation, for it tends to hide under 
water the surface thus affected. Evidence, therefore, of 
subsidence is very valuable ; and this movement, more- 
over, has probably played a more important part in the 
history of the world than elevation, for there is reason to 
believe that most great formations have been accumulated 



t^-k' 



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V 

^--- 

t" 



'-n 




whil 



st the bed of the s 



o^ was sinking. 




may 



sometimes be inferred from the form of the coast-land ; 



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FT 



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190 



GEOLOGY. 



r .^t. VI. 



for Instance, where a line of cliffs, too irregular to have 
been formed by elevation alone, plunges precipitously into 
a sea so profoundly deep that it cannot be supposed that 



the now deeply submerged portions of the cliff have been 



simply worn away by the currents. The direct evidence 
of subsidence, if not witnessed by man, is almost confined 
to the presence of stumps of trees, peat-beds, and ruins 
of ancient buildings, partly submerged on tidal beaches. 
Ancient buildings may sometimes afford such evidence 
in imlikely situations : it has been asserted, that in one 
of the volcanic islands in the Caroline archipelago there 
ruins with the steps covered by the sea. A^-ain, at 
Terceira, at the A.s^ores, there is an old church or monas- 
tery said to be similarly circumstanced. 

Coral Beefs* — The most important point with re- 
spect to coral reefs, which can be investigated, is, the 






depth at which the bottom of the 



/, 



ceases to be covered with a continuous bed of living 
corals. This can be ascertained by repeated soundings 



with a 



heavy and vei-y broad bell-shaped lead, armed 
with tallow, which Mall break off minute portions of the 
corals or take an exact impression of thu... . it can thus 
also instantly be seen how soon the bottom becomes covered 
with sand. This limit of depth ought to be ascertained 
in diirercnt seas, under different latitudes, and under dif- 
ferent exposures. For collecting specimens of the corals, 
it is to be feared that the dredge „ould become entangled, 
but chains and hooks may be lowered for this purpose. 
There is reason to suspect that different species of corals 

* The only -n'ork specially writion on this suln'ect is ' The Structure 
and Dist!'--fiou of Corai Keefs; by Mr. Darwin. 



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Sect. VI.] 



GEOLOGY. 



191 




cov in difierent zones of depth ; so that in collecting 
sp'^^imens, the depth at wliich each kind is found, and at 
tvhich it is most abundant, should be carefully noted. 
It ought always to be recorded whether the specimen came 
from the tranquil waters of a lagoon or protected channel, 
or fiom the exposed outside of the reef. The small reefs 



*»T -t 



* r 



d 



ub ) in 



o 



atolls not a single reef rises within several fathoms of the 

level. It would be a curious point to ascertain 




...rae 



whether the corals in these cases consisted of the same 
species ; and if so, on what possible circumstance this sin- 
gular difference in the amount of their upward growth 
has depended. 

Any facts which can elucidate the rate at w^hich corals 
«an grow under favourable circumstances, will ever be 
interesting : nor should negative facts, showing that within 

iven period reefs have not increased either lateral! 
or vertically upwards, be neglected. In a full-grow 
forest, to judge of its rate of growth, a part must be first 
cut down ; so is it probably with reefs of corals. The 
aborigines of some of the many coral islands in the great 




J 

n 




oceans might perhaps adduce positive facts on this head ; 
for instance, the date might be known when a channel 
had been cut to float out a large canoe^ and which had 
since grown up. 



For the classification of coral reefs, the most important 



point to be attended to, is the inclination of the bed of the 
adjoining sea; and secondly, the depth of the interior 
lagoon in the case of atolls, and of the channel between 
the land and the reef, in Encircling or Barrier, and in 



, 1 




^M 




! 



I 

^ 



192 



GEOLOGY 



9 



[Sect YL 



Fringing reefs. Whenever it is practicable, soundinrrg 
ought to be taken at short ascertained distances, from 
close to the breakers in a straight line out to sea, so tlr * 



a sectional outline might be protracted on paper. In 
those cases in which the bottom descends by a set of 
ledges or steps, their form ought to be particularly 
attended to ; and whether they are covered with sand or 
by dead or living coral ; and whether the corals dilll., on 
the different ledges : the same points should be attended 
to within the lagoon, wherever its bed or shore is step- 
formed : the origin of these steps or ledges is at present 
obscure. In the Indian and Pacific oceans there are 
entire reefs, having the outline of atolls or lagoon-islands 
lying several fathoms submerged ; there are likewise de- 
fined portions of reefs both in atolls and in encircling reefs 
similarly submerged. It would be particularly desirable 
to ascertain what is the nature of these submerged sur- 
faces, whether formed of sand or rock or living or dead 
corals. In some cases two or more atolls are united 
by a linear reef; the form of the bottom on each side 
of this connecting line ought to be examined. Where 

tolls or reef-encircled islands stand very near each 
other, the depth between them might be attempted by 
deep soundings: the bottom has been struck between 
ome of the Maldiva atolls. Generallv the form and 



n v) il 



nature of the reefs encircling islands ought to he com 



pared 
atolls. 



Ill 



every respect with the annular reefs forming 



On the shores of every kind of reef, especially of atolls 
and of land encircled by barrier reefs, evidence of the 
slow sinking of the land should be particularly sought for; 






for '-- 






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Sect. VI.] 



GEOLOGY. 



193 



for instance, by stumps of trees, the fouudation-posts of 
sheds, by wells or graves or other works of art, now stand- 
ing beneath the level of high- water mark, and which there 
was good reason to believe must have once stood above 
its level. The observer must bear in mind that cocoa-nut 
trees and mangroves will grow in salt-water. If such 
evidence be found, inquiry ought to be made whether 
earthquakes have been felt. On the other hand, all 
masses of coral standing so much above the level of the 
sea that they could not have been thrown up by the 
breakers during gales of wind, at a period when the reef 
had not grown so far out seaward, should be investigated 
and their height measured. There is reason to believe 
that some coral-reefs have been thought to have been 
upraised, owing to the effect of the lateral or horizontal 
extension of the reefs having been overlooked ; for the 
necessary result of this outward growth is gradually 



±- -. 






C"_ 



to break the force of the waves. 



so that the rock 



\ 



now further removed from the outer breakers, become 
worn to a less height than formerly, and the 



more 



mland corals not being any longer constantly washed by 
the surf, cease to live at a level at which they once flou- 
rished. It is indispensable that specimens of all upraised 
corals, and especially of the shells generally associated 
with thorn, should be collected ; for there can be no doubt 
that ancient strata containing corals, have in some in- 
stances been confounded with recent coral-rock. The 
importance of ascertaining whether coral-reefs have un- 
dergone, or are undergoing, any change of level, depends 
on the belief that all the characteristic differences be- 

Atolls and Encircling reefs on the one hand, and 



tween 



b' t 



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191 



GEOLOGY. 



[Sect. VI. 



Fringing reefs on the other, depend on the effect produced 
on the upwardly-growing corals hy the slow sinking or 

rising of their foundations. 

A thick and widely-extended mass of upraised recent 
coral-rock has never yet been accurately examined, and 
a careful description of such a mass— especially if the 
area included a central depression, showing that it origi- 
nallv existed as an atoll— is a great desideratum. Of 
what nature is the coral-rock ; is it regularly stratified or 
crossed by oblique layers ; does it consist of consolidated 
fine detritus or of coarse fragments, or is it formed of 



upright corals embedded as they grew ? Are many shells 
or the bones of fish and turtle included in the mass, and 
are the boring kinds still in their proper positions ? The 
thickness of the entire mass and of the principal strata 
should be measured, and a large suite of specimens col- 
lected. 



In conclusion, it may be re-urged that the young geo- 
logist must bear in mind, that to collect specimens is the 
least part of his labour. If he collect fossils, he cannot 
go wi^ong ; if he be so fortunate as to find the bones ol 
any of the higher animals, he will, in all probability, make 
imnortant discovery. Let him, however, remember 



an "! 

that he will add 



reatly to the value of his fossils 




that he will aaa greaiiy lo uk vaiuc ux ...^ ^— ^ j 

iabellinff every single specimen, by never mingling those 



n-om two formations, and by describing tlie succession of 
the strata whence they are disinterred. But let his aim 
be higher : by making sectional diagrams as accurately as 
possible of every district which he visits (nor let him sup- 
pose that accuracy is a quality to be acquired at willj, by 



I 



! 



JU^ 



P' 



Sect. VI.] 



GEOLOGY. 



195 




i. 



t 




t i 



^4 



collecting for his own use, and carefully examining nu- 
merous rock-specimens, and by acquiring the habit of 
patiently seeking the cause of everything which meets bis 
eye, and by comparing it with all that he has himself seen 
or read of, he will, even if without any previous know- 
ledge, in a short time infallibly become a good geologist, 
and as certainly will he enjoy the high satisfaction of con- 
tributing to the perfection of the history of this wonder- 
ful world. 



J > 



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196 



) 



[Sect. VII. 




Section VII, 



ON OBSERVATION OF 



EAETHQUAKE PHENOMENA 



By 11. MALLET, A.B., Mem. Ins. C.E., M.R.LA. 



Whenever a blow or pressure of any sort is suddenly 
applied, or tlie passive force of a previously steady or 
slowly variable pressure is suddenly either increased or 
diminislied, as these affect material substances, all of 
which, whether solid, liquid, or gaseous, are more or less 
elastic, then a pulse or wave of force, originated by such 
an impuhe. is transferred, through the materials acted 
on, in all directions from the centre of impuhe^ or in such 
directions as the limits of the materials permit. The 
transfer of such an elastic rvave is merely the continuous 
forward movement, of a change in the relative positions, 
of the Integrant molecules or particles, of a determinate 
volume, of the whole mass of material. 

Ordinary sounds are waves of this sort in air. The 
shaking of the ground felt at the passage of a neighbour- 
ing railway-train is an instance of such waves in solid 



round or rock. A sound heard by a person under water, 




or th^^ ^hock felt in a boat lying near a blast exploded 
under water, are examples of an elastic wave in a \u\md. 

The velocitv with which such a wave traverses, varies in 
difterent materials, and depends principally upon the de- 






tib 



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Sect. VIL] 



EAETHQTJAKE PHENOMENA 



107 



gree of elasticity, and upon the density in any given one. 
This transit period is constant for the same material, and 






is irrespective of the amount or kind of original inipul 
for example, in air its velocity is about 1140~in water 
about 4700— and in iron about 11,100 feet per second 
all in round numbers. 



Iciii 



Thus, if one stand upon a line of railway near the 
and a heavy blow be delivered at a few hundred feet distant 
upon the iron rail, he will almost instantly hear the wave 
thruuo-h the iron rail — directly after he will feel another 
wave through the ground on which he stands — and, lastly, 
he will again hear another wave through the 




' ; and if 



there were a deep side-drain to the railway, a person im-- 
mersed in the water would hear a wave of sound through 
it, the rate of transit of which would be different from any 
of the others— all these starting from the same point at the 

same moment. 

The size of such a wave — that is, the volume of the 
flifinlflPi^fi nartiolpft of fhp -material in motion at once, de- 



pends upon the elastic limits of the given substance, and 



upon the amount or power of the original impulse. By 
the elastic limit in solids is meant the extent to which 
the particles may be relatively displaced without fracture 



or other permanent alteration : thvis glass, although much 



more perfectly elastic than India rubber, has a much 
smaller elastic limit. 

Nearly all such elastic waves as we can usually observe 
originate in Impulses so comparatively small that we are 
only conscious of them by sounds or vibrations of various 
sorts, the advancing forms of whose weaves are impercep- 
tible to the eye ; but when the originating impulse is very 



V . 






L 



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^ 



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-I 







EARTHQUAKE PHENOMENA. 



[Sect. VII. 






violent, and the mass of material suddenly acted on very 
great, as in an earthquake, the size of the wave becomes 
so great as to produce a perceptible undulation of the sur- 



5 



face of the ground, often visible t( 

transit bodies upon the earth 

through their own inertia), thrown down, &c. 



are disturbed (chiefly 



earth q 



of a wave of 



directmn, from vertically upwards to horizontally in any 
azimuth, through the surface and crust of the earth, from 
any centre of impulse or from, wMre than one, and which 
may he attended with tidal and sound waves, dependent 

-■ and upon circumstances of position as to 
This truth has not yet been fully and 
ex]>eriixientally demonstrated. It is of the highest im- 
portance to a wide region of science that observations 
should be made, enabling it to be so. 



sea and land. 



5? 



Observers in earthquake countries should make them- 
selves familiar with the usual features, and with the 
succession of events, and concomitants which with a certain 
sort of regularity apply to all earthquakes. For this Sir C. 
Lyell's 'Geology,' in loco, will be sufficient. The greatest 
shocks are not the most insti active, except as to secondary 
effects; but every great shock is ususHy followed by several 
smaller— the first should therefore be viewed as a " notice 
to observe " the latter carefully. 

The phenomena of every earthquake may be divided 
into — 1st, Primary, or those which properly belong to the 
transit of the wave or waves through the solid or watery 
crust of the earth, the air, &c. ; 2, Secondary, or the effects 
produced by this transit—and both must be kept distinct 






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Sect. VI 1. 1 



EAllTHQUAKE PHENOM 



^T 4. 



■jy 



from co-exlstent forces, such as those of volcanic eruption, 
permanent elevation or depression of land, &c., winch, how- 
ever closely they may be connected with the originating 
impulse of the earthquake, form no true part of it— they 



merely c 



omplicate its phenomena 

of 



rally conceived to be a sudden volcanic outburst, or sudden 
upheaval or depression of a limited area, or sudden frac- 
ture of bent and strained strata. This origin should be 
carefully sought for, as to its nature and position. 

An earthquake may have its oripn either inland or at 
sea ; and as this may be, a different set of phenomena 

In the former case we may ex- 



ist, The Great Ea 



will present themselves, 
pect, in the following order 
or true shock, a real roll or undulation of the surface tra- 
velling with immense velocity outwards in every direction 

dentFi 






from the centre of impulse. If tliis be at a 

below the surface, the shock will be felt principally hori- 

zontally ; but if the origin be profound, the shock which 

is propagated from it in every direction in spherical 

shells will be felt more or less vertically ; and in this case 

also we mai/ be able to notice two distinct waves, a greater 

and a less, following each other almost instantaneously ; 

the first due to the originating normal wave, the second 

to the wave viLrating at right angles to it. It we can 

find the point of the surface vertically over the origin, 

and the direction of emerirence of the shock at a distant 

point or at several, we can find the depth of the origin 

from the surface. 

There are, therefore, certain lincb at points in which the 
shock. In passing outwards from the origin, is simulta 



1-^^ 'V'- 



200 



EABTHQUAKE FHEXOMENA. 



[Sect. VII. 



neously felt on tLe earth's surface. These may be called 



Coseismal lines. 



An erroneous notion, of the diracKsions of the great earth 



wave must not be formed from its being called an undula- 
tion — its velocity of translation appears to be frequently as 
much as thirty miles per minute, and the wave or shock 
moving at this rate often takes ten or twenty seconds to 



pass a given point ; hence its length or amplitude is often 
several miles. 

During the passage of the great earth wave or main 
undulation, a continuous violent tremor or short quick un- 
dulation (like a short chopping sea) is often felt. This 
arises from secondary elastic waves, upon the surface of 
the great earth wave, like the small curling or capillary 



waves on the 



surface 



of the ocean 



swell, but v\ 



hlch 



within its mass are analogous to the dispersion of light. 
The physical cause of these is not here in point; but 
it is very desirable that the interval in time between 
these minor oscillations should be observed by a seconds 



watch. 



When the roll or undulation of the earth wave, 
coming from inland, reaches the shores of the sea (unless 
these be precipitous, with deep water), it may lift the 
water of the sea up, and carry it along on its back, as it 
were, as it goes out into deep water; for the rate of 
transit of the shock is so immense that the elongated heap 

subside laterally. This 



of w 



ater lifted up has not time to 



/: 



comparatively sinall, and nearly the same as that of the 
earth-wave, when close to the shore on a sloping beach ; 
and where the water is still, any observations that can 



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Sect. VII.] 



EARTHQUAKE PHENOMENA 






01 



be made as to the height of this fluid ridge will afford 



of the height of the 



earta-wave or 



nide indications 

shock. 

Earthquakes, whether at sea or on land, seem to be 

only accompanied with subterranean noises when strata 
are fractured or masses of matter blown away at volcanic 

Where such is not the case, the two preceding 
are'the only waves to be expected from an earthquake of 
inland origin ; but when fracture occurs, then at the 
moment of the shock, or very slightly before or after it, 

wave, through the earth, ; 

and at an interval longer or shorter after this, 4th, the 



origms 



Sound 



Sound 



Again, when the origin of the earthquake i«! under the 
ea (and such seems to bo the case with most great earth- 



^'■il 



quakes), we may expect in the following order— 1. The 
great earth-wave or shock ; 2. The forced sea-wave, which 
is formed as soon as the true shock or undulation of the 
bottom of the sea gets into shallow water, and forces up a 
ridge of water directly above itself, which it brings in to 



shore, and which seems to be the cause of that slight dis- 
turbance of the margin of the sea often noticed as oc- 
curring at the moment of the shock being felt ; 3. The 
sound-wave through the earth (as in the former ease) ; 
4. The sound-wave through the sea, which arrives after 
that through the earth, but prior to 5. The sound-wave 
through the air. Where the original impulse is not a 



single impulse, but a quick succession of these, or a single 
impulse extending along a considerable line of operation, 
passing aAvay from the observer : the sound-waves will be 
rumbling noises, and may be confounded in each medium 

k3 



2 



09 



EARTHQUAKE PHENOMENA. 



[Sect. VII 



more or less : and where no fractures or explosions occur, 
the sound-waves may be wholly wanting. 

Lastly, and usually a considerable time after the shock 
the great sea-wave rolls in to lar.d. This is a wave of 
translation : a heap of sea-water is thrown up at or over 
the origin of the earthquake by tiie disturbance of the sea- 
bottom, and begins to move off in waves like the circles on 
a pond into which a pebble is dropped : and its phenomena 
depend upon hi ws different from any of the other (elastic) 
w^a\c3 of earthquakes. 

The original altitude (above the plane of repose of the 
fluid) and volume of this wave depend upon the suddenness 
and extent of the originating disturbance, and upon the 
depth of water at its origin. Its velocity of translation 
on the surface of the sea varies with the depth of the sea 
at any given point, and its form and dimensions depend 



upon this also, as well as upon the sort of sea-room it has 
to move in. In deep-ocean v/ater one of these waves may 
be so long and low as to pass under a ship without being 
observed ; but as it approaches a sloping shore its advanc- 
ing slope becomes steeper, and when the depth of water 
becomes less than the altitude of the wave, it topples over, 



gre 



Sometimes, how- 



ever, its volume, height, and velocity, are so great that it 
comes ashore bodily and breaks far mland. The direction 
from which it arrives, at any given point of land does not 
necessarily infer that in which the 



oriedn mav be 



; as 



this wave may change its direction of motion greatly, or 
become broken up into several minor v/aves in passing over 
water varying much and suddenly in depth* or in following 
the lines of a liighly-indented or island-girt shore. 



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Sect. VIL] 



EARTHQUAI^E PKENOMENA. 



203 



Observations of eacli of these classes of waves Viiicli we 
have thus brieflv described may be made either dirently 






hj the aid of instruments, specially provided or ex- 
temporaneously formed, or indirectly by proper notice of 

which they produce, on objects upon the 



certam 




earth^s surface. 

Direct observations l^y complete self-registering Seis- 
mometers do not come within our present scope. We, 
therefore, proceed to direct observations with extempora- 
neous instruments on the earth-wave or shock. The ele- 
ments necessary to be recorded aro such as will enable us 
to calculate — 1. The direction in azimuth of the v/ave's 
motion ; and (if it have an upward motion) also its direc- 
tion of emergence at the points of observation. 2. Its 
velocity of transit. 3, Its form — i. e. its amplitude and 

altitude. 

If a common barometer be moved a few inches up and 

down by the hand, the column of mercury v/ill be found to 
oscillate up and dow^n in the tube with the motions of the 
instrument and in opposite directions, the range of the 
mercury depending upon the velocity and range of mo- 
tion of the whole instrument. A barometer 6xed to the 
earth, therefore, if we could unceasingly w^atch it. would 
give the means of measuring the vertical element of the 
shock-wave ; and if w^e could lay it down horizontally, it 
would do the same by the amplitude or horizontal ele- 
ment. Tliis we cannot do ; but the same principle may 
be put into use by having a few pounds of mercury, and 



some 




las: 



R 



L 



one eud, and open at the other ; the bore behig about 



three-eighths of an inch in diameter, and each limb about 



■^Z^i^^- 



-f 



204 



EARTHQUAKE PHENOMENA. 



[Sect. VIL 



Se( 



eighteen iijubes long. 



We shall also require some common 
barometer tubes of the same calibre : the open end beincr 
turned up like an inverted syphon, and equal in bore to the 



(See Ftp, 4.) 



L 



the horiaontal, the others for the vertical elements. 

To fit the L tubes for use, fill each partly with mercury, 
and so adjust it that a column of six inches in length shall 
be in each limb of each tube, when held as in Fi^. 1 ; 

" r 

the limb a b horizontal, and the vertical 
column being supported as in a baro- 
meter. Tie four of these tubes so pre- 
pared together, back to back, so that if 
one horizontal limb face the north, the 



Sealed end 



Fiq. L 




5 



others shall face east. 




Sealed ends. 



, and west respectively, as in 

In this position 




ia. 2 



tube 



secure them all down 
upon a broad stout board, 
that can be itself fixed to 
a surface of rock, or other 
flat fixed surface of the 
earth. 

An index or marker must now be prepared for each 

or ono of these cut a common piece of card two 




E 






inches long by rather more than five-eighths of an inch 
wide, and double it down the long way, so that the two 
segments shall stand at rather less than right angles to 



each other ; cut a cylindrical slice of cork one-eighth of 
an inch thick, of five-sixteenths of an inch diameter, so 
that it will go easily into the tubes (these being all three- 
eighths of an inch in diameter) : attach the bit of cork 
with glue or sealing-wax to the end of one wing or seg- 



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six 
whi 

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Sect. VIL] 



EARTHQUAKE PHENOMENA, 



205 



L 



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«^ 



ment of the folded card, leaving the other free, and 
thrust the whole into the horizontal limb of the tube 
until the cork just touches the mercury, and so for the 
others. This marker is shown at full mze (about) in 



Cork. 



Free side. 



Fig, 3. 




Attaclied side. 



The edges of the card having a certain amount of 
elastic extension, must slightly grip the inside of the tube- 
It will now be found that if horizontal motion be given 
to the system of four tubes — say, from south to north, 
that the marker in the southern tube will be pushed 
southwards a certain space by the movement of the mer- 
cury, and will remain to point out the space when the 
mercury has returned to rest. If the motion be in some 
direction between two adjacent tubes—say, from south- 
east to north-west. — the markers in the south and e 
tubes will both show a certain motion, equal in this case, 
but in others with a certain ratio to each other, by which 






.o]_ 



the direction between the cardinal points may be cal 
culated. 

For the vertical element : let the barometer- 
tube Fiff. 4, be filled with mercury, so that about 
six inches shall starid in the open end a^ into 
which thrust a marker, as in Fiff. 3, and about 

F 

twelve inches in the sealed limb ; place this 



Fig. 4. 



vertically, and secure it to a fixed mass of rock, 
a heavy low buildino;, or large tree ; the amount 
to which the iHtarker is found moved up in the 
tiihe will give the altitude of the wave ; and it 
is obvious, that by the conjoint indications of 




f 






206 



EARTHQUAKE PHENOMENA, 



[Sect. VII 



the four horizontal tube-markers and this vertical one, 
the direction of emergence of the wave is determinable. 

These iiistriiraents are of the nature of fluid pendulums. 
They are much superior to common solid pendulums, for 
these uses, where the dimensions of the shocks are mo- 
derate ; but where these are great and very violent, 
heavy solid suspended pendulums, with a quick time of 
vibration, will be found alone applicable : the seconds 
pendulum for lat. Greenwich will always be desirable* 
Where fluid pendulums are not attainable, a solid pen- 
dulum to answer some of the purposes may be thus 
prepared : — Fix a heavy ball, such as a four-pound 
shot, at one end of an elastic stick, whose direction passes 
througli its centre of gravity : a stout rattan will do. Fix 
the stick vertically in a socket in a heavy block of wood 
or stone, and adjust the length above the block as near 
as may be to that of the seconds pendulum frjr Green- 



wich. 



Prepare a hoop 




of wood, or other convenient 
material, of about eight inches diameter ; bore four 
smooth holes through the hoop in the plane of its circle, 
and at points ninety degrees distant from each other ; 
adjust through each of these a smooth round rod of wood 
(an uncut pencil will do well), and make them, 
greasing, &c., slide freely, but with slight friction through 
the holes. 

Secure the hoop horizontally at the level of the centre 
of the ball by struts from the block, and the ball being in 
the middle of the huop, slide in the four rods through 
the hoop until just in contact with the ball. 

It is no., ^.bvious that a shock, causing the ball to os- 
cillate in any direction, will move one or more of the rods 



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ect. VIL] 



EARTHQUAKE PHENOMENA. 




i 
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through the holes in the hoop, and that they will remain 
to mark the amount of oscillation. 

A similar apparatus, with the pendulnra-rod secured 
horizontally (wedged into the face of a stoiit low wall, for 



>le) 



'11 
will 




ive the vertical element of the wave. 



Two of these should be arranged, one north and south : 

the other east and west. 

It will be manifest that the observer must record 
minutely the dimensions and other conditions of such 



apparatus, where it is not permanently kept, to enable 
calculations of scientific value as to the wave to be made 

F 

from his observations of the range of either fluid or solid 

pendulums. 

A common bowl partly filled with a viscid fluid, such 



as molasses, which, on being tlirown by oscillation up the 



side of the bowl, sliall leave a trace of the outline of its 



surface, has been often proposed as a Seismometer. 



method has many objections : it can only give a 



r ■ 111 • 



rude 



approximation to the direction of the horizontal element , 
but as it is easily used, should never be neglected as a 
check on other instruments. A common wooden tub, 
with the sides rubbed with dry chalk and then carefully 
half filled with water or dye stuff, would probably be the 

best modification. 

Another extemporaneous instrument for measurement 
of vertical motion in the wave may be som.etimes useful. 
Make a spiral spring of eighteen inches or so in length 



by twisthig an iron wire of one-eighth of an inch diameter 



round a rod of about 1| inch diameter (the staff of a 
boarding-pike) ; suspend it by one end vertically from a 
fixed point, and fix a weight (a twelve-pound shot will 



i^ 



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4 



208 



EARTHQUAKE PHENOMENA. 



^ 



m 



[Sect. VII, 



'I 



^^ 



do) to the lower end, and below and in a line passin»T 
vertically through the centre of gravity of the weight fix 
the stem of a common tobacco-pipe ; let the lower end 
of this stem just dip into a deep cup filled with pretty 
thick common ink or other coloured fluid : the action 
of this needs no description. 

The preceding instruments suffice at once to give the 



direction of transit of the earth-wave and its dimensions ; 
its rate of progress or transit over the shaken country 
remains to be observed. 

Several distant observers, with chronometers, will of 
course best observe this, but such observations cannot be 
very numerous or extend over a large tract of country ; 
yet it is most desirable that a network of such observing 
points should be stretched over the shaken country. For 
this purpose common house-clocks, situated at several 
distant points, may be easily arranged, so that the pen- 
dulum shall be brought to rest and the clock stopped at 
the moment that the shock passes. 




Fw. 5 



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Sect. VII.j 



EARTHQUAKE PHENOMENA. 




mon clock. To fit it for this purpose bore two holes of a 
quarter of an inch diameter, one through either side of 
the clock-case, at a b, at the level of the lowest point of 
the pendulum-bob and in the plane of it& vibration ; round 
off the edges of these holes, and grease them. 



In the centre of a piece of fishing-line or stretched whip- 
cord, make a loop and pass it round the screw or other 
lower projection of the pendulum bob ; pass the two free 
ends of the cord out, one through each of the holes in 
the sides of the clock-case ; provide a squared log pf 
lieavv wood of about five or six inches thick each wa 
and from four to five feet in height ; cut both ends off 
square, and stand the log uprigiit on one end directly 



^3 r 

J' 



opposite the dial of the clock. 

Measure off equal lengths of the cord at each side of 
the pendulum, and make fast their extremities to the 

close to the 



g, c d, 



two opposite sides of the upright lo 
top ; bring the log backwards from the clock now,, until 
the pendulum being at rest, both cords are drawn tight ; 
and then advance the log two or three inches towards the 
clock, so that the cords may be slacked down into a fes- 
toon or bend at each side of the pendulum, and within 
the clock-case, so that the pendulum may have room to 
swing freely ; and very slightly w^edge the cord to keep it 
so, through the holes in the clock-case, and from the out- 
side ; see that the log rests firmly and upright upon a 



firm floor ; and now set the clock a-going. 



Tlie leng 



the cords, or the distance of the log from the clock in re- 
lation to its height, must be such that if it fall towards 
the clock it 



r 

hall bring the cords up tight before the 



grouD 



It is now ob- 









^. 



fe 



( 



'W^^ 



210 



EARTHQUAKE PHENOMENA. 



[Sect. VII. 



gect. 



■i 



vious that in whatever direction the h)g may fall, it Mill 
arrest the motion of the pendulum and stop the clock 
within less than a second of the true time of transit of the 
wave at the spot. 

If the adjustments are similar for all the clocks this 
error v/ill be constant for them all ; and if the true time 
be noted at the principal station it can be got for the 

rest. 

Clocks with seconds pendulums cmly should be chosen 
for this use. They should be all set by one chronometer, 
and their errors afterwards taken. 

Where conyenient, the pendulupas should be all placed 
to swing north and soutli, or east and west ; and in this 
case the sides of the logs will face the cardinal points, 
and the directions of their fall (where not entangled) be a 
rude index of that of the wave. It will be also desirable 
to place a bovvd of fluid to mark direction with each 
clock. 

The positions chosen for the clocks must vary with cir- 
cumstances, but they should, as far as possible, surround 
the principal station ; their distances apart must be con- 
siderable, as the speed of the wave or shock is immense 

probably five miles is the ordinary minimum, and thirty 
to fifty miles a convenient maximum. Such arrangements 
should be made as rapidly as possible after the first shock 
has given the expectation of others in succession. 



When practicable, the following method of fitting 



conmion clocks may be adopted advantageously. — Let 
a^ Fig. 6. be the pendulum-bob ; fix a pin of stout wire 
into a hole in the centre of it, J, at right angles to the 
plane of vibration ; cut two small mortices through the 



side 
ligb 

of a: 
in fr 



% ' 



K 



edg( 
like 
and 

seen 

afc: 



desci 



flat s 



of 



aa 



It 

a; 




i^e sJi 



I 



Sect. VII.] 



EARTHQUAKE niENOMENA 



211 



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d 



s 



sides of the clock-case, so that a lath of deal or other 
light wood, of about an inch and a half wide by a quarter 
of an inch thick, may be passed through from c to d, just 
in front of the bob and clear of it. 

Mark the length of the arc of vibration on the lower 
edge of the lath, and cut this length into nicks or teeth 
like a racli, of about three-eighths of an inch in depth 
and breadth each. Place the lower edge of the lath 
boijzontally, and just above and clear of the pin b; 
secure the end of the lath J by a wire pin or stud, as a 
fixed point, so that the end c is free to move in an arc of 
a few inches up and down round ^ as a centre. 



rem 



are 



/= 



descril)ed, but cut its upper end to a square pyramid, the 
flat surface at the top being reduced to about a quarter 
of an inch square ; adjust the length and position of the 
log, so that it shall form a support for the end of the 
lath c, as in the figure. 

It is obvious that the moment the log / is overthrown 
by a shock the lath will drop at the end c (which should 
be slightly weighted), and the teeth or rack nicks catch- 



^:r. 






V- 



^' r 



t* 



-; 



-I 




212 



EARTHQUAKE PHENOMENA. 



[Sect. VII. 



ing the pin h of the pendulum-bob will stop the clock ; 



on examining which, the dial will show the 



time to a 



second when the shock took place^ and the tooth in the 
rack will show at what part of the arc of vibration the 
pendulum was arrested, which will obviously give the 
time of the shock to a fraction of a second. 

This method may be applied to any form of clock, and 
with any length of pendulum. 01::^rvation should be 
accurately made by a seconds watch of the total duration 
of the shock in passing the observer's station. 

Returning now to observations to be made indirectly 
upon the earth-wave, or by its effects, consisting principally 



ot 



buildin 



down 



- T 



; 2. On bodies projected, displaced, or inverted; 
3. Bodies twisted on a vertical axis, with more or less 
displacement. 

The observer must bear in mind that all these motions 
arc due to the inertia of the bodies at the moment of the 
wave transit. The first tendency, therefore, of every 
body is to fall in a direction contrary to that of the wave's 
motion ; but this is often perplexed by mutually-support- 
ing bodies, as cross walls — by the direction of the wa\e 
being one, in which a fail is impossible, as when passing 
very diagonally through a long line of wall — by disinte- 
gration from the first wave, though so altering the condi- 
tions of the bodies (walls, towers, &c.) short of producin 
a feill, as that the dislocation and fall produced by a suc- 
ceeding one is not contrary, but m the same direction as 
the wave motion. Long walls, in or nearly in the line 
of wave motion, are often split vertically, but not over- 
tnrown. When the shock emerges at a large angle to 







Cijt. 



\ 



tlie 

or 



1 

fr 



(litioi 
Bodi< 
obeli 
due 



,--a: 






\.'>- 



i 



tiirou 
wbicl 
body 



L 



iCv 



J 



Wly 



see ^ 



class 

teria 
tion 

anio 

ditio 

num 

ofth 



A] 



cla 



ss 



upsid 
such 

111 

coiin:, 



■ -^^_ j;' -*v."^^^-is«^j:r . , 



r. 



\ « 



V 



I 



* • 



Jk -*^' 



4 



If 

,1^ f 



1 



r*' 



t ^ 



1 




i^iti. 



*lie 



.«- 



I, Hi 



1 : 
ft ^^ 




Sect. VIL] 



EARTHQUAKE PHE 



^NOMENA 



213 



the horizon bodies are often projected, as stones out of 
or from the coping of walls: the size, weight, form, 
cement, sort of stone, distance thrown, and all otlier con- 
ditions of projection should then he carefully noticed. 

twisted on a vertical axis (such as the Calabriaa 



Bod 



;S 



Geology ') 



s^ 



upposed 
due to a vorticose motion of the earth. This motion 
arises fr jm the centre of gravity of the body lying to one 
side of a vertical plane in the line of shock, which passes 
through tliat point in the base on which the body rests, in 
which the whole adherence, by friction or cement of the 
body to its support, may be supposed to unite, and wlrich 



of 



The observer who 



fully masters these mechanical conditions of motion will 
see what elements he must collect, so that the motion 
impressed on bodies thus twisted may be used to calculate 
the velocity, &c. of the wave. All observations of this 
class, to be of scientific value, must comprise the ma- 
terials, size, form, weight, sort of cement, base or founda- 
tion of the bodies disturbed, and measurements of the 
amount, &c. of disturbance, with any other special con- 
ditions which occur; and these will always be very 
numerous, and demand the utmost alertness and scrutiny 

of the observer. 

Amongst the doubtful phenomena on record of this 
class are inversions of bodies, such as pavements turned 



upside down (see Lyell, ' Calabrian Earthquake ') 
such cases deserve special attention. 



In traversincr an extensive city, or thickly built-over 
country, to observe the shattered buildings— having first 
known the general line of motion of the wave— the 



S 
€- 



m 






X 



1 

t 



I 



^ 



[ 

i 






^ 
^ 
i 

^ 



^ii:-_I 



=5a 



V J : u. 



J 
J 



I 

E 



i! 




r 



'¥^5 



214 



EARTHQUAKE PHENOMENA. 



[Sect. VII 



has 



observer should remark if its direction of motion 
appeared to change as it passed along, and obtain decisive 
evidence of its actual transit, for sometimes the 



leave 



imultaneously 



of country, where the origin is deep-seated, and nearly 
veiiically below. Changes in the rate of transit hori- 
zontally, or in the force of the wave, should be noted by 
its effects on similar objects at distant spots. These 
changes m.ay be expected at the lines of junction of dif- 
ferent rocks or other formations. Evidence should also, 
if possible, be got of any breaking up of the primary 

felt 



wave into 




where only one has occurred further back. 

All evidence should, as far as possible, be circumstantial 
Nature rightly questioned never lies ; but men ai-e prone 
to exaggerate, at the very least, where novel and startling 
events are in question. 

Various local conditions must be recorded : — the nature 
of the geological formations at the spot, not merely the 
underlying rock, with the directions of its bedding, lami- 
nation, joints, &c. ; but the character of surface, the depth 



and description, of its loose materials, their variations and 
extent, tlie geological formations of the surrounding dis- 
tricts from whence and towards which the earth-wave 
travels especially. The deeper a knowledge can be got 
by exposed sections, &c. of the rocks of the shaken district 
the better, the proximity or otherwise to volcanic vents, 
active or paa?ive, the character of surface of the country 
shaken, mountain or plain, even or liroken, solid or fis- 
sured ; if the latter, their general directions, dip, &c., 
whether dry or flooded, and the effects on the elements of 



\i 



I 



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V 



r 



.,,1 1 



1 



»>'- 



li 



iiig 



fi 



IC 



^r^oc."^ 



slip% 




a 



co: 



A/ 



of r:^ 
may t 



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:-»fl 



n 






f\ 



tie? 



distin 



* • 



on ' 



prodi 

river' 
slioii] 

from 

feinec 

imme 

SlOlHf 



sh 



ouJd 



-*-*^fe^r,-tj^^ 'i:_>- ^ 



Q 



Sect. VII.J 



EARTHQUAKE PHENOMENA. 



215 



(i 



i '' 




1 t 






^ h 




^5 




1 

' Tiff. 



• .^rT' 



f ■ 



^ -« 



1' , 



1' 

f 



ese c 



onditions. 



the wave, of changes in any or a.11 of th 

Places least and most affected by the shock, and those 

fivo from any, and their local conditions, to be particularly 

noted. 

Referring now to secondary phcaoinena^ or efR^cts result- 



ing from th 



e 



(other 



sted surfaces 



measures of it), we should observe falls of rock, or land 
slips^ to which most of the conditions of shattered building 
apply. Land-slips change their directions frequently, i)i 
consequence of moving over curved or tw 
of rock : thus the previously straight furrows of a field 
mav be found twisted after an earthquake. Scratches or 
furrows engraven on rocky surfaces by such land-slips 

should be looked for. 

Sometimes great sea- waves are produced by the fall into 
the sea of rock or land-slips, which need to be carefully 

r 

distinguished from the true great sea-wave produced by an 
original impulse of the sea-bottom. Land-slips often dam 
rivei*s, fill up lakes ; and various changes of surfiice again 
produce basnis for new lakes, to be filled by the changed 

The circumstances, as far as possible, 
should be accurr^-ly observed, and the chain of events 
unwound, and all such phenomena cautiously separated 
from actual ejections of water (temperature to be ascer- 
tained), which are said sometimes to have happened on an 

immense scale. 

spout it up at the 

moment of shock. Wells alter their water-level, and 
sometimes the nature of their contents. The directions of 
the fissures and any changes in the temperature of wells 

fissures of 



nver-eourses. 



Fissures containing water often 



hould be noted. Ejections from holes or 



K- 




tt'. 






.-.^ 



216 



EARTHQUAKE PHENOMENA, 



[Sect, VII. 



Strange liquid or solid matters, sometimes of dry ashes 
or dust, are recorded, and occasionally fiery eructations 
have occurred, especially near volcanic centres, and 
blasts of steam-vapours, or gases, whose chemical cha- 
racters should be in all the above cases observed, as 
far as possible. The dust of overthrown buildings must 
not be confounded with these. Fissures, often of profound 
depth, open and remain so, or close again : their directions, 
dimensions, time and order of production, and closing up 
and the formations in which they occur, to be noted ; 
bodies engulphed to be detailed, as future organic remains. 
Fissures most probably arise from the range of displace- 
ment of molecules by the passing wave, exceeding the 
elastic limit of the materials disturbed. Permanent 
elevations and depressions of the land usually accompany 
earthquakes, and are of much importance to science. 



5 



ILo modes of observing these rather belong to geology 
proper. The half-tide level must in all cases be taken 
the datum-line, and opportunities alor 



as 




wharfs, or inland, along mill-streams or irrigating channels, 



&c., diligently sought for, where evidence may be trust- 
wortliily collected of changes of depth of water. Occa- 



sionally local but widely-extended permanent elevations 
or depressions accompany earthquakes, which seem to 
result from lateral compression, and not from direct 
elevatory forces. Ihese should be distinguished from the 
preceding. 

Rivers are stated to have sometimes run dry during 



gam 



to flow after the shock. 



This is presumed to arise either from the transit of an 
earth-wave along their courses up stream, thus damming 



sect' 



1 







p} 



as 



SI] 







by 



4 

t 



wi 



ill 



ani- 
on 
osdl'i 

sir all 

■ 0' 

calm, 

t?J''n 
as toi 
at the 



(> 




the 



fully 

The . 

rate t 
(or i* 

heforc 

Putti, 
th^ 

sepai 

ft 

someti 

earth 
each 



( 



1 



M 



_ J _-tl^ ■■r-^V- 



Sect. VI L] 



EARTHQUAKE PHENOMENA 




«r 



kr 



1 . 







V 



1 



»■ 



tf*.**. 








I 

i 



tn *** 



^ 



«M- 



.t*i G 







«tfi ' 



ofF their sources, or from sudden elevation of the land, and 
as sudden depression. This demands careful observation. 
Observations of the forced sea-wave^ whether produced 
by the earth-wave going out to sea or coming in from it. 
will be nearly the same. It is desirable to find its height 
above the surface of repose referred to half-tide level, 
and its length or amplitude ; but from the extreme rapidity 
of its production and cessation, or conversion into small 
oscillatory waves lapping on the beach, and its generally 
sni^ll altitude, observations are extremely difficult — they 
are only possible v> I;en the surface of the sea is perfectly 
calm, and then must be left to the skill of the observer in 
taking advantage of local circumstances, and of evidence 
as to the visible circumstances of this wave, which occurs 
at the instant the shock is felt. 




Observations of the vjaves of sound throu 
the sea, or fresh water and the air, are indicated pretty 
fully by the description of these waves already given. 



The sound-wave through the earth travels at the same 
rate as the shock, or earth-wave ; it is in fact the shock 
(or its fractures) heard. Notice if the sound is heard 



before, along with, or after the shock is felt. An observer 



^ 



putting one ear in close contact with the earth, and closing 
the other, will hear the sound-wave through the earth 
separate from that through the air. So also an observer 
immersed in the sea will hear the sound-wave through it 
sometimes without any complication of that through the 
earth. 

The character and loudness of flie sound through each 
medium, and the places in an extensive district vfhere 
each was heard loudest and faintest, should be noted. 






^1 






^r. 



^■^ 



-^ 



1^ 



^■i»^^ 



- \ 



218 



EARTHQUAKE PHENOMENA. 



[Sect. VII. 



Sect 



-i 



-^ 



-^^ 






The duration of the sound from first to last, through 
either medium, accompanying each shock, is important. 

Observations on the ffreat sea-wave should embrace, 
for each wave, its height, its amplitude or length, its 
velocity and direction of translation. The height to be 
taken above the plane of repose of the fluid, and referred 
to half-tide level. These waves, when on their grandest 
scale, defy any methods of :;imeasurement (unless by 
soundings where they break before coming to the beach), 
but chance observations of their results, such as the 
height to which they have reached on mural feces of 
rock, or on such buildings, &c. as may withstand them, 
or eve-si^ht observations made at the moment of transit 
of the crest of the wave, cutting distant objects; but 
when of a manageable si^e, the height of the crest may 
be pretty closely obtained by the traces on wharfs, 
buildings, &c., or on posts or piles driven into the littoral 
bottom. This may be taken from any convenient fixed 
points of level, and all ultimately referred to half-tide 
level as the datum for all earthquake observations as to 
level. 

The sextant may be occasionally used to get the eleva- 
tion of the crest of the passing wave, several observers 



making a simultaneous observation of an expected wave 



The velocity of the wave may be got by noticing from a 



suitable position, by a seconds watch, the time of its 
transit inwards between two distant points which should 
have an interval of water whose depth is or may be known. 
Islands off the land are advantageous posts for this 
purpose. 

The length of the wave (while entire} should be sought 



\ 



for 
of 



fir 
foi 

to 

de 

dii 

tin 
be; 

sue 

tiiv 

in 

of 

at 
lati 
wli, 
m 

din 
rep 

gre 

the 

litt 
bef 



( 



("rui 
the 




^t 



I 



Sect, VII.] 



EARTHQUAKE PHENOMENA 



219 



lA 



V I 








^ 

\ 



i 



f 




• « 



r r 




I 



it 






IT 




I 



« t 



^ ' 




t 



* 



r 



ti'. 



** 



I 



.r 



It**"- 




1 , 






for by a similar method ; a knowledge of Its length and 
of the depth of water infers its height. 

The point approaching the coast at which the wave is 
first observed to break, when capable of being accurately 
found, gives the height of the wave, which is here equal 



to the depth of the soundings. Tliis breaking point and 



depth should always be anxiously tried for. Besides the 
dimensions of the wave, observations should be made on 
the interval of time after the great earth-wave, or shock, 
before the great sea-wave comes in, reckoning from the 
commencement of the shock ; how inany such waves in 
succession ; what is the period between each ; what are 



their relative dimensions 



what changes 






re observable 



in the directions whence they come at the same point 
of coast, and what are the several in-coming directions 
at various points along a great stretch of coast (the 
latter must be had usually from collected testimony) ; 
what reflux from the beach before or after the cominfr 
in of the wave ; after the wave has come in and l»roken, 
what oscillatory waves are producedj their character and 
dimensions ; is the level of the surface of the sea in 
repose, the same before and after the subsidence of the 
great sea-wave and its secondary or oscillatory waves ; 
what the state of tide above or below half-tide level at 
the moment of shock and of great sea-wave. 

As accurate a section as possible of the form of the 
littoral bottom, beach, offing, and out to deep water, should 
be got by soundhigs in the line of the coming in of the 
wave, and laid do^ii on paper ; and, where possible, a 
cruise should be made out to sea in the direction whence 
the waves came, to look for pumice, dead fish, volcanio 

l2 



'^ 



Hj 

^ 



r 



^ 






I 



i 



i 





220 



Se< 



EARTHQUAKE PHENOMENA. 



[Sect. VIL 



C5 



allies, or other indications of the distant or 

of disturbance* 

The secondary effects of the great sea-wave most worthy 
of remark are the materials, if any, carried in from deep 
sea, such as loose niineral matter, new animal or vegetable 
forms. Unless the water is very deep close to land this 
is unlikely to occur^ as the range of transferring power of 
a great sea-wave (wave of translation) is only equal to 
the length of the wave itself. ■ 

If fish or testacea are thrown inland into fresh water, 
the effects on them should be noticed. 

In recording the transporting power of the wave (?'. e. 
its absolute transferring power, without reference to dis- 



tance), the size, form, specific gravity, and lithological 
character of rocks or boulders moved, the distance moved, 
and height lifted are to be given. The base on which 
moved, if rock, the scratches or farrows produced. The 
mode of motion ; if swept or roiled along. Obstacles 



overcome in their progress. Whe 
materials are moved. 



gravel 



or 



loose 



^ an estimate of the mass moved, and 
to what distance ; the character, external and internal, 
of its deposition ; the mutual relations of its fine and 
coarse parts. The eflPects on buildings variously exposed ; 
on vertical and sloping sea-walls ; on steep faces of clifTs. 
The denuding effects of the wave in sweeping off sand, 
gravel, trees, animals, &c. The disruption and abrasion 
of stratified rocks, especially of nearly level and nearly 
vertical beds. Effects of vertical sea-walis or cliffs in the 
reflection or extinction of the wave. 

Specimens should be taken of the rock of which very 
rcTiiarkable boulders or architectural fragments moved by 



^ 

! 



\ 



1, 



t 



fr 

01 



sc 



\i 

n 



r( 
tr 

SI 

sh 



rot 



tl 



>f 



siz 

ft. 
thi 
tri^ 
cli< 

fX\r 



h 



\ 



i 



for 



( 



gai) 

the 

are 
b 



-J 



ei 



and 
pre 



I 



-^^^J^:^^ 



>-J^ 



Sect, VIL] 



EARTHQUAKE PHENOMENA 






Ir 






f 



P 



» 



t 




f 



J 



ri 




; 



■ t ^ 



.^ 







« 




f 



^'- 



f*. 



*- *- 



^ 



^ 




cast 



I 



iBures, caY 



ties, wells, &c. 
oil land ; of mineralized or fouled water suddenly made 



so ; of gases evolved from 




Where possible, 



immediate chemical qualitative examination should be 



made. 



Specimens in particular should be brought home of the 
rocks or other mineral masses through which the speed of 
transit of the earth-wave has been carefully observed, 
such as will enable the modulus of elasticity/ of the mass to 
be determined. Where this is rock, three specimens 
should be taken of maximum, minimum, and average 
hardness, density; and compactness, as representatives of 
the whole shaken district, noticing especially in stratified 
rock the depth from surface of ground and from top of 
the formation at which taken : each specimen to be of a 



r-_. 



size enablin 




least 



feet in length by four inches square. Where convenient, 
this operation may be done on tiie spot. Where the dis- 
trict is a deep detrital or alluvial one, the depth and 
characters of the loose materials should be carefully 
observed, and illustrative specimens, as far as possible, 
brought home. 

Collateral conditions to be observed are — ^barometer be- 
fore, during, and after the earthquake ; thermometer, rain- 
gauge ; hydrometer and electrical state of the air during 
the phenomena ; magnetometrical observations where these 
are practicable ; all unusual meteorological appearances to 
be noted ; the state of tide at time of each shock ; the rise 
and fall of tide at the place ; and any tidal anomalies 
produced after the earthquake. Active volcanic phe- 



I 



222 



EARTHQUAKE PHENOMENA. 



[Sect. VII. 



S€ 



nomcna occurring before, during^ or after the earthquake, 
in adjacent or distant regions, to he recorded. 

Records or trustioorthj traditions are to be sought for 
in volcanic countries or those neighbonring to them, as to 
the state of activity or repose of these vents for a long 
period prior to and during the earthquake ; also as to 
their state before and during any previous earthquakes 
all remarkable facts as to which should be collected. 

should 

be transcribed for the times, correlative to the above 
records. 

Any changes of permanent level of sea and land that 
accompanied former earthquakes that are on record should 
be obtained, with their particulars ; whether the same points 
have been affected in successive eartliquakes, and by suc- 
cessive upheavals ; whether the same or different volca- 
noes were in action during successive earthquakes. 

may be advantageously made of the lines of 



Where meteorological or tidal tables exist, thev 




direction through the country in which the shock was 
simultaneously felt ; coseismal lines : also of the incoming 



directions or cotidal lines of the efreat sea-waves on a 




long coast-line, shov/ing origin where possible. Maps of 



'-m 



issures formed in relation to the coseismal lines, and 
generally sketches of all visible remarkable effects of the 
earthquake on natural or artificial objects. The effects 
of earthquakes on the lives of men and animals ; statistics 
of mortality : modes of entombment by the convulsion, 
bearing on future organic remains ; burying of objects 



of liuman art ; production of presumed epidemics or 
pestilences, &c, are all worthy of notice. 

Observers will do well, to consult at least the following 



h 

r 



\ 



I 

b 



( 



1 
I 

1 



at 



a 



IS 



ii{ 



s 



be 






ao 
ea 



I 



r 



Sect VII.] 



EARTHQUAKE PHENOMENA 




«l 



^ 



kr 



I -.. 



. i 



Jr. 



r 



m 



4 {ae 



b 



iV 



^ 



! 



■^ 



ft 



L " 



J 



.^1 



ible. 



^f 



t» _ 



r 



^ 



•^ ^' 



f 



'3. 







«Ui' 



Vfi^ 



ft 



works, to enable them the better to grasp beforehand 
the subject of earthquakes:- — Lyell's ^Geology/ passim; 



Doiomieu's 'Account of the Great Earthquak 

theoretic views ; Hers 



r^ 



Cit JYi i ■'■a ' O, 



bria/ neg 




his 



j: 



:\rt. 



) 



'Tides' C 
' Report on 



Waves. 



dia Metro- 
Brit. ASBO., 



1844; Mallet's 'Dynamics of Earthquakes/ Trans, Royal 
Irish Acad,, 1846 ; Hopkins's ' Report,' Trans. Brit, Ass^, 
1847-48, and the several narratives of earthquakes. 




It sometimes happens that a shock of earthquake is felt 

at sea, at gi'eat distances from land, and over profound 

depths ; a sudden blow is felt, as if the ship had struck 
a rock. 

The earth- wave emerging from an origin closely beneath, 






is here transferred to the ocean, through which it p 
upwards as an elastic wave, wdth the same speed as the 
sound-wave through the sea. When such an event occui's, 
and circumstances are favourable, we should look out for 
the passage almost immediately in form of a single, low 
swell, of the great sea-wave, which may be formed directly 



over the origin, at no very great distance off. A cruise 




about and soundings may be made in search of indications 
(piunice, &c.) of the ori 
be indicated by the degree of lateral stroke felt at the 
moment of the shock and by the direction of the great 



sea 



■ «i 



S' 



- 1 





t 



^ 



k- 



•N 



■#*■ 



224 



^i 



[Sect. VIIL 



Section VIII. 



MINEKALOGY 



By sir henry DE LA BECHE, C.B., F.E.S., &c. 



y^ 



^ 



A GLANCE at the best treatises on mineralogy, even 
those wherein the matter is most condensed^ is sufficient 
to show that a profound acquaintance with this science 
can only be acquired by long-contliMied study, and by 
means of a competent knowledge of certain other sciences, 
the aid of w^hich must be obtained properly to com- 
prehend the internal and external structure and chemical 
composition of minerals. The naval man may never- 
theless nccomplish much, more especially respecting the 
mode of occurrence and probable origin of minerals under 



• , * 



resear 



to the catalogue of known substances of this class. 

When we see a diamond, we consider that we have 
before us an arrangement of the particles of carbon in 
the most perfect manner, that is, these particles have 
been enabled freely to adjust themselves, so that they 
have filially been aggregated in a definite form. So also 
a ruby or a sapphire presents us with the particles of 
alumina (with usually some slight admixture of other 
substances, such as oxide of iron, silica, &c.) arranged in 
a definite and most perfect manner, the conditions having 
been such that they also could freely adjust themselves; 






\ 



c 






it 

si 

a 

t 

t; 



¥ 



n 

a 



Si 



cc 

th 



ra 



ar: 
Tl 

eh 



c, 



b 



G 



bei 






ill 



t 



vr 



1-^ 



St 



lv4 



gre 



h 



as 



Pres 
exac 



\ 



I 



L -^ _ H 



Sect. VII L] 



MINERALOGY. 



225 



T 






J 

i 

4 






} 



1 



k 



T. 



^ r 



■\ 



i 



\ 



uaa 



a U '• 



^ 



-that 



\a 



1 if y 



car 






Hif 



-^ 



> 



f 



i'^ ■ 



••Mi** 



1 ■ 



' ^ 



,)iP 



h ' 



k 




with this difference, however, in the case of alumina, that 
it IS not one of the simple substances which chemists con- 
sider carbon to be, but a compound of a metal (aluminium) 
and of oxygen. The ruby and sapphire are well-knowji 
transparent minerals, but it is not necessary that the par- 
ticles of even a simple substance should be arranged in 



- X 



Jar 






what* in common lanL?;uap;e, mav be termed a r»erfect 
manner to make the mineral transparent. We may take 
as familiar examples of the contrary crvBtals of gold, 
silver, and copper. 

As the knowledge of mineralogy advanced, it was dis- 
covered that there existed an intimate connexion between 
the chemical composition and physical structure of min 
rals when their constituent substances could form those 

r 

arrangements of their particles known to us as crystals* 
This led to the view that vvhen minerals possess the same 

chemical composition, tlicj also always present the same 
crystalline system. 

This is now known not to be strictly true. Tlie same 
bodies have been found to occur under two different and 
incompatible forms, and to this the term dimorphism has 
been applied. Certain substances have also been dis- 
covered to replace others, without altering the form of a 
mineral, and to this the name isomorphism has been given. 
The known dimorphous bodies are very few, not more 
than about. 10 in 350 crystallized minerals. The sub- 
stances which are isomorphous being ascertained, no very 
great difficulty is experienced on this head. M. Dufrcnoy 
has well remarked that " it is not necessary, in order to 
present the same composition, that minerals should 
exactly contain the same weight of their simple consti- 

l3 



V- 



t 




MINERALOGY. 



[Sect, VIIL 






tiient substances ; it is sufficient that there is an exact 
relation between the bases and the acids they contain , or 
between their ison^orphous substances."* 

The external geometric forms of minerals were, as far 
back as 1784, discovered by Bergman and 



Bergman and Haiiy not 
always to be those which might be considered funda- 
mental or primary, since many were found capable of 
bein^ split or divided into other forms, represeiitin 




the solid arising from the free adjustment of the compo- 
nent particles, the body of the crystal and external form 
being made up of an aggregation of many primary crys- 
tals, or of some modification of a primary crystal. Of 
the aggregation of primary crystals the common mineral, 
calcareous spar, affords a familiar example. The funda- 
mental crystal of carbonate of lime is a given rhombohe- 
dron, yet the external forms of this mineral are very 



varied, so mucn so 



that 



the Comte de Bourn on was 



enabled to describe nearlv 800 modifications of them. 
The primary form alone, as external, is much more rare. 
The crystallization of carbonate of lime also well illus- 
trates dimorphism. The common kind, as we have seen, 
has a fundamental crystal of a given rhombohedral form, 
but there is another kind, named arragonite, wherein, 



* Dafrenoy, 'Traite de Mineralogie/ tome i. p. 19- This is a most 
excellent workj and should be in the hands of those who desire an ex- 
tended knowledge of mineralogy. We may also mention Phillips's 
* Elementary Treatise on Mineralogy/ an English edition by Allan, and 
an American edition by Alger: Dana's ^System of Mineralogy' (New 
York and London) ; Beudanfs ' Traite Elcmentaire de Mineralogie / 
Rammelsberg's - Handworterbuch des Cheniischen Theils des Mineral- 
ogie f Blum's * Die Pseudomorphen des Mineralreichs f Rose's * Elements 
der Krystallographie;' Dr, Karsten's * System der Mineralogie ' (Ber- 
lin ^ and others. 






r 






1 






b( 



d 



a 



tl 



^ 



.Sect. VIIT.] 



MINERALOGY. 



227 



U 



tto 



u 



T 



*Q^>r 



\.. 



^^^^^i 



• A 



\m 



, } 




IC 



**" 



\ 






b 




1^ 



f 



^1 



4 . 



ft 



f * 



¥ 



It 



though the proportions of carbonic acid and lime are 
precisely the same, the crystals ere hexagonal prisms. At 
one time this very different crystalline stroctm^e was at- 

r 

tributed to the presence of a small per ceatage of car- 
bonate of strontia (from 0'7 to 44) ; but as arragonite 
has been found solely composed of carbonate of lime^ tl 






opinion seems abandoned. It has been lately stated that 
when carbonate of lime is crystallized from a warm solu- 
tion it takes the form of arragonite, and when from a 
cold one that of com.mon calcareous spar. It should be 
added, that the packing of the particles of arragonite 



is 



such that the specific gravity of this mineral is greater 
than that of common carbonate of lime. 

At one time, though crystals of definite forms, constant 



internal strii"*:ure5 and chemical composition, allowing for 



isomorphous substitutions, were being obtained in a mul 



titude of chemical processes carried on upon the great 
scale, as well as in the laboratory, much stress was laid 
upon distinctions between artificial and natural products* 
Now, however, that bodies, once only discovered in 
various positions among rocks, have been formed arti- 
ficially, sometimes by accident, at others by design, there 
appears a disposition to look at inorganic matter more 
generally, however convenient it may be to describe those 
bodies by themselves which have been found in some 
natural position. 

Among the researches which have tended to break 
down the barriers once thought to exist between natural 
and artificial minerals, the recent labours of M. Ebelmen 
may be mentioned as the most remarkable, since among 
the minerals produced are some commonly considered as 






228 



MINERALOGY. 



[Sect. VIII. 



k^ 



insoluble by our processes and infusible in our furnaces, 
and some of them moreover belong to the class of gems. 
M. Ebelmen inferred that^ inasmuch as many substances 
in solution in water crystallize when the water is 
evaporated, he would obtain certain minerals if he dis- 
solved their elementary 

of igneous fusion) 



substances 



state 



in some body (in a 
so doing, and which 
at a still higher temperature would evaporate and leave 
the elementary substances to adjust themselves in a crys- 
talline form. Most perfect success attended the labours 
founded on this view, and in this manner he obtained 
crystals identical with rubies, spinels of various colours, 
soberyl, chrysolite, and others. Crystals of emerald 
were also formed from pounded emerald. The crystals 
of clirysoberyl were of sufficient size to have their 
optical properties tried, and were found identical with 
those of the natural mineral. 

To classify the natural substances described under the 



Cli 



head of niioeralosfv, 



very various methods have been 



adopted, chiefly, however, divisible into those based 
upon their external characters or chemical composition. 
The following is that adopted by M. Dufrenoy in 1845, 
founded on chemical comnosition. 



P 



I 



i 



VI 



1 



^ 



^ 






¥ 



? 



1 



i 






■^. 



Sect. VIII. J 



MINERALOGY. 



229 



r 



k 







i 



t 



t 



t 

I 

IT 



1 



f 



I 



• « 




FiBST CLASS.^Smp/c SM&s.aHC^s, each h'.g one of the essential principles- 

of compound minerals. 

Electro-negative bodies ; never acting &s a base with the bodies of 
other classes, and always forming a constituent part of binary 



compounds. 

Genus. 

I. Oxygen, 

II. Hydrogen. 

HI, Nitrogen. 

IV. Chlorine. 

V. Bromine. 

VI. Iodine. 

VII- Fluorine. 
VIII. Carbon. 
IX. Boron. 



Genus. 

X. Silicium. 
XI. Titanium. 
XII. Columbian, 

XIII. Sulphur. 

XIV. Selenium. 
XV. Arsenic. 

XVI, Phosphorus. 
XVII. Vanadium, 
XVIII. Antimony, 



Genus. 

XIX. Tellurium. 
XX. Mereurv. 
I XXI. Molybdenum 

XXIX. Tungsten. 

XXIII. Chromium. 

XXIV. Osmi 



1^' 



XXV. Rhodium. 



Second Class. — Alkaline Salts, 



The difterent salts composing this class are soluble in water, and 
possess a marked taste. 



Genus. 

XXVI. Ammonia. 



Genus, 



Genus . 



XXVII. Potash 



I XXVIII. Soda, 



Class 



V 



Earths 



The substances composing this class have a stony aspect ; pure, they 
are without colour or of a milky white ; they are not generally hard. 
With the exception of corundum, none scratch glass; their specific 



:*^ 



an 



exception to this general rule. 



Geniis. 



XXIX. Baryta. 
XXX. Strontia. 



Genus. 

XXXI. Lime, 
XXXII. Magnesia. 



Genus. 



XXXIII 



XXXIV. Alumina 



Fourth Class. — Metals, 

This class comprises two divisions, each distinct in aspect : 

1. Native metals, and the combination of -many metals with each 

other in a metallic state. 

2, Combinations of metals with oxygen or with acids. 

The minerals of the first division have generally a metallic lustre, 
which give? them a remarkable external character, distinguishing 
them from other minerals. 

The combinations of the metals with oxygen or with acids rarely 
present this lustre j in xhis respect they range among the 



''■,. 



Morals 



S'i 



t 



-i 



I 



1 






O 




MINERALOGY. 



[Sect VIII 



Sec 



of the class silicates. They nevertheless, for the most part, possess 
a peculiar colour, guiding us in their study ; their specific gravity 
is generally high, and almost all upon assay immediately give a 
regulus or metallic scoria. 



Genus» 

XXXV. Cerium, 
XXXVI, Manganese, 
XXXVII, Iron, 
XXXVIII, Cobalt, 

XXXIX, Nickel. 
XL, Zinc. 



Gonus. 

XLi, Cadmium, 
XLii, Lead. 
xi.iii. Tin, 
XLiv. Bismuth. 

XLV. Uranium. 
XLvi. Copper. 



Fifth ChAss.— Silicates. 



Genus. 

XLVII, Silver, 

XLviii. Gold. 

XLix. Platinum, 
L. Iridium, 
LI. Palladium 



The 



long known especially as stones. They form two distinct groups 
the hydrous and the anhydrous silicates : the first are soft, and 
easily dissolve in acids ; the second are hard ; a portion with diffi- 
culty soluble in acids ; the greater part insoluble in them. 
The specific gravity of the silicates :'s between 2'5 and 3-6; a small 
number only approaching the latter limit. 



Genus. 

Lii. Aluminous silicates. 
Liii. Hydrated aluminous sili- 

cates. 

Liv. Silicates of aluminaj of 

lime, or their isomorphic 
substances. 

LV, Aluminous and alkaline 

silicates, and their iso- 
morphic substances. 



Genus, 

and their isomorphic sub- 
stances. 
Lvii, Non-aluminous silicates, 
LTiii. Silico-aluminaies, 
JAX. Silico-fluates. 
Lx. Silico-borates. 
Lxi. Silico-titanates, 
Lxii. Silicc-sulphurets. 
Lxm. Aluminates. 



Lvi. Aluminous hydrated sili- j lxiv. Substances of unknown 



cates, with alkalies, lime, 



* ^ « 



composition. 



Sixth Cj^Ass.—Combiistibles. 

The mineral constituting this class for the most part still present 
traces of their organic origin; when crystallization has, as m 
wellite, effaced this essential character, we are reminded of it bv the 
nature of the elements which enter into the composition of the 
mineral. 

The combustibles of organic origin generally bum with flame at a 
moderate temperature, giving out a marked odour. They are soft ; 
their specific gravity, generally very low, does not exceed 1 • 6. 



\ 




t 



\ 



\ 



i 

r 

L 

r 



1 



X 



mil 
sep 

vai 



J 



-.. r-V*' 



por 

fou: 



w 



:1 

T ■ 



Hi 

net 
;e.( 
ter 
ela; 
hi 

por 

aw: 
com 

the 
or-~ 



-*< 



H 



\ 



11} 



4 

I 



■-■*^*™^'^^ .r^-" 



^ 



I 







V 



T t I, 



iii 








ft* I**- 








It 

r 

t 



xf 




■ ■) 



■ll,. 



lyv 




' J » 



Sect. VIIL] 



MINERALOGY. 



231 



They may be divided into the following:— 

1. Resins, 2. Bitumens. 3. Fossil combustibles, comprising an 



thracite, coal, lignite, and peat. 



Genus, 

XXV. Resins, 



Genus. 



Genus. 



Lxvi. Bitumens. 1 lxtii. Fossil combustibles 



. ^ 



O 



Under these 67 heads are now classed more than 500 
minerals, supposed really to differ sufficiently to be 
separated, independently of many merely considered 
varieties, or accidental. 



It will be obvious that a voyager, especially when his 



as 



general time may he occupied with other duties, (only a 
portion of it applicable to mineralogy, and that irregu- 



) 



e 



himself ftimiliar with all 



^V 



found he will have little difficulty, and by practice he 
will readily detect them when presented to his attention. 
Those which form the constituents of rocks it is especially 
necessary to learn and distinguifh, since so much of 
geological importance often turns upon their proper de- 
termination. Those which are referable to the useful 
class should engage his attention, since while, on the one 
hand, valuable ores of the useful metals and other im- 
portant substances are often neglected (even in our mining 
districts unusual though valuable ores have been thrown 
away at no remote times), on the other, many a mineral, 
commercially worthless, is treasurt^d up, often even to 
the neglect of those of high value, some particular bril- 
liancy of appearance or fancied resemblance to precious 
or metallic substances having; misled the collector. 

However desirable it may be to consider inorganic 
matter as a whole, the conditions under which its parts 






^ 






i 



\ 



i 

4 



4 



i 



232 



MINERALOGY. 



[Sect. VIII. 



have been fc-und to combine either naturally or artificially 
being only regarded with reference to the general sub- 
ject, so that the natural bodies, commonly termed 
minerals, merely constitute a portion of this whole, it is 
important that the voyager 



be enabled to distinguish 



natural minerals, both as respects science and its appli 



cations. 



The foregoin 




sification 



on 



chemical composition, if he possessed no other means of 
distinguishing minerals from each other than chemistry 
afforded him, he would in many instances, from the want 
of the needful space and appliances on board ship, have 
the extent of his mineralogical labours greatly abridged. 
At the sam_e time, with a box containing certain chemical 
substances, a shght apparatus, and a blowpipe, he will, 
after a little practice, find his power to distinguish 



anticipate. 



greater 



Postponing for the present the assistance which these 



means of distinguishing minerals chemically, by the wet 



or dry m,ethods, may afford, it may be convenient to refer 
to the mode of aggregation of the particles of minerals 
intemally, as also to their external characters, without 

upon those refinements which require the appli- 
cation of a high order of investigation. For this reason 
we pass by those properties of minerals which are termed 



enterui 




beautiful and important as they are, and 



so 



valuable with reference to a knowledge of the arrange- 
ment of the component particles of minerals. So also 
with regard to their electrical properties and the effects 
f heat upon them. Should the voyager eventually find 
mself sufficiently interested in the studv of mineral^, he 



«ect. 



thes 



1 




ft 



k' 



1. 



like I 

% 

Accit 
The 

tore, 



exam 

a ml 
chari 
pseu 
renc 

thiri 
orgs 
arra 
prisj 
para 
com; 

4. 

meta 
5. 

is d- 
6. 



1. 



i 



f 



\ 

h 

I 



^^J3g a *g ^?^ - - 



k 



l- 



! 



%*« 



^■ 



^ 



^ 



t 



c ■ 



•«p I 



1 



u 



fe- 



»> 



I 



i 



Sect. VIIL] 



MINERALOGY. 



233 



must consult works and memoirs dedicated especially to 

these researches. 

With respect to the characters of minerals, they have 
been arranged under the following heads by M. Du- 
frenoy : 

1. State cf Aggregation.— While minerals are commonly solid, some, 
like native mercury and certain bitumens, are liquid; so that they may 
be distinguished as liquid, friable, and solid. 

2. CoZowr.— Colours are either constant or accidental : when the former, 



and 



important 



term 



peroxide of iron is red, sulphuret of lead a peculiar blue-grey, and so on. 
Accidental colours are chiefly due to the mixtures of mineral substances. 
The peculiar appearance known as chatoi/ant depends upon the struc- 
ture^ and is referred to the cleavage-planes, the refl_ect*id light from 
which changes according to their position. Labradorite is a good 

example of this property. 

3. Form.— This term is not intended to include the geometric form of 
a mineral, which is considered under the head of its crystaliographic 
characters, but comprises only common, imitative, pseudo-morpuous, and 

pseudo-regular forms. The firsi 
rence of the mineral in mass, fragments, plates, or in an amorphous 
condition. The second to its occurrence in grains, nodules, &c. The 
third, when a mineral takes the form of a pre-existing body, whether 
organic or inorganic. The term pseudo-regular is applied to such 
arrangements of parts as are presented by basaltic columr. 3 and other 
prismatic forms of igneous rocks, apparently also extending to the 
parallelepipeds arising from the intersection of the divisional planes, 
commonly termed the joints aiid cleavage of rocks. 

4. Zz/.^fre.~Such as vitreous, waxy, silky, nacreous, adamantine, semi- 
metallic, and metallic. 

5. Transparency.— Varying from diaphanous through semi-diapha- 
nous, translucent, and translucent at the edges, to opaque. Rock crystal 
is- diaphanous, chalcedony translucent— both different aggregations of 

the particles of silica. 

6. Fracture.— This is distinguished as lamellar, granular, fibrous, 

radiated-fibrous, schistose, and compact. 

7. Hardness.— Thh character is relative. The following is a scale 
of hardness proposed by Mohs, and somewhat comm.only adopted: 

1. Lamellar Talc. 2. Selenite (crystallized sulphate of lime). 
3. Iceland spar (carbonate of lime). 4. Fluor spar (fluate of 



M 



T^" 



J-- V- 



■-?'^'?, 



^JS--- - 



ET'-^^.-iS 



:c^ v--^-^K*^-ri 



231 



MINEKALOGY. 



[Sect. VIIL 



\ 



Sect. 



1 



1 



-"^ 



lime). 5. Pliospiiate of lime. 6. Lamellar felspar. 7. ijock 
crystal. 8. Topaz. 9- Euby or Sapphire. 10. Diamond. 

S. Toiighness.—This character consists in the resistance ^hich a 
substance offers to be broken or torn. A soft mineral may be very 
tough, such as sulphate of lime; a hard one readily fractured, as 
flint ; and some are both hard and tough, as jade. 

9. The ScratcL—Tv'mls for hardness give a scratch and poAvder, which 
are useful in the determination of minerals. Thus the ores of iron 
named hematites, gi^re a red or yellow ochre powder, which at once dis' 
tinguishes this mineral from the concretionary ores of manganese, the 
powder of which is black. 

10. The Stahu— This character is only applicable to a few minerals, 
and those soft. It consists in marking paper or linen with the mineral--^ 
chalk and plumbago thus leave marks. Plumbago may be thus dis- 
tinguished from sulphuret of molybdenum, Tvhich it otherwise much 
resembles, 

11. Unctuosity,—Many minerals are soft and soapy to the touch, suci 
as talc and serpentine, magnesian minerals. 

1 2. Flexibility, —SeYeral are flexible, such as native silver and copper. 
Some are both flexible and elastic, as mica. 

13. Df/c^?7%'.— Principally applicable to native metals. Though 
sulphuret of silver and halloysne cannot be lengthened under the 
hammer, they are nevertheless termed ductile by the mineralogist. 

14. Tasce.— Only applicable to certain substances, distinguished as 
bitter, sweet, salt, &c. 

15. Adhesion to the tongue .—GeneYBlly sufficient for distinguishing 
argillaceous from pure limestones, 

16. Odour. Such as of the bitumens and other similar substances, or 
by means of breathing on or rubbing a mineral, ^hen a peculiar smell 
is perceived. 

17. Coid,~The feeling of cold when a mineral is placed in' the 
In this manner rock crystals and gems can be distinguished 

rom glass and enamel, which otherwise may be made closely to imitate 
them. 

18. Sound.—Thm property must be taken in its ordinary acceptation, 

and not with regard to the motion given to the molecules by percussion. 

Some substances are very sonorous ; phonclite is so named from this 
property. 

^ 19. Weight,~This property also to be taken in its common accepta- 
tion, the mineral being only supposed to be weighed roughly in the 
hand. In this manner carbonate of lime, sulphate of baryta, and car- 



hand. 



4^ 



bonate of lead may be easily distinguished. 






app^ 



Ti 



n. 



V 



stanc 

of t- 



a-- 



refer 

ties r 
furtb 
bedc 

Su 






1 



their 
befe. 
task, 



1SS0( 



» ] 

coadi 

Fo 
is tis 

line ( 

flask 
stopp 

is fin 

tube. 

theai 
soth'^ 

esca 



^ 



k 



i. 

fc. 



p 



«f 



I 



if 



I 



+>-' 




»rj 




i 




1-v 




Sect. VIII.] 



mi:, ^ralogy. 



23 



These characters may be regarded as aids towards the 
approximate knowledge of a mhieral, and as such may be 
useful, more especially to one who may in the first in- 
stance be desirous of availing himself, with as little loss 
of time as possible, of the differences or resemblances of 



an 



f T 



to 



minerals he may have collected, endeayomnng 
refer them to known substances, so that while opportunl 
ties may continne to bo afForded he might institute stil 



further search for any minerals respecting which it may 



1 



be desirable to collect additional information. 

Supposing the voyager in possession of minerals col- 
lected on some excursion, he will find it useful to try 



their 



gravi 



be sufficiently calm for the purpose. This is no difficult 
task, and the use of the needful apparatus for the purpose 
is soon acquired.* As the specific gravity of minenils, 

* Much may be done with tlie common balance made for the purpose, 
-ftdiercby, after 'weighing the body in the air, it is weighed in the water, 
which should be distiUed water, and enough can be got by dexterously 
condensiDg the steam coming out of a common tea-kettle. 

For very exact determinations a flask of the kind herewith represented 
is used, c (i is a ground-glass stopper, made so 
exactly to fit, that its bottom coincides with the 
line a h, so that the volume of the interior of the 
flask is constant, A capillary tube traverses the 
stopper through its length, so that when the flask 
is filled any excess of water escapes through this 

tube. The flask full of water is first weighed, 

and then the weight of tlie mineral is taken in 

the air. The mineral is then placed in the flask, 

so that it remains full, after the volume of water 

equal to that of the substance inserted has 

escaped. If now the fiask, with the mineral in 

it, be weighed, the difference of weight gives that of the volume of water 

disjdaced, and by finding the relation of the weight of the mineral to 

that of the water, the specific gravity is obtained. If the substance tried 




ff* 



m 



'-iC\-^ 



>- 



y*' * 



236 



MINERALOGY. 



[Sect. VIII. 



when these are pure, is considered to be intunately con- 
nected with their chemical composition, a knowledge of 
ii becomes a useful pi-eliminary inquiry. It may be 
almost unnecessary to remark that the specific gravity of 
a mineral is obtained by first weighing it in air, then in 
^vater, that the loss it sustains in water gives the weic^ht 
of the displaced water, and that, by dividing the weight 
in air by the loss, or the weight of an equal bulk of water, 
the specific grayity is obtained. Thus if W be the weight 
of a substance in the air, W^ itn weight in water, W— W^ 
will be that of the displaced volume of water, and 

the specific gravity. 



W 



w 



TV 



It has been above stated that with the exceptions 



Siiif 



-^^ 



arismg from dimorphism and isomorphism^ the chemical 
composition and crystallization of mineral substances bear 
a marked relation to each other. Whatever the forms 
of the ultimate atoms of matter or those of the integrant 
molecules* of the substances of the minerals may be, very 
defi^nite and constant fundamental polyhedral solids are 
enerally found accompanying definite chemical compo- 




ihese 



sitions (with the exceptions mentioned), and the study of 

forms has led to the science of cry stall ograpky. It 
would be out of place here to attempt to enter upon this 
highly interesting branch of knowledge ; it will be found 



be in powder, it is important that aD air-bubbles be remoyed, and if 
porous, that the air in the pores be replaced by water. 

* It has been consU^red that all crystals may be derived from a 
prism, and thus that all minerals might be composed of prismatic par- 
ticles closely joined to each other without void spaces. On the utiier 
hand polyhedral forms have been thought most probable, void spaces 
being interposed between the molecules, and this the researches of M. 
Biot on lamellur polarization are considered lo have proved. 




Vi 



tJ^' 



V* 



d 



sketc 

been 

Exp 

led 1^- 



ionif. 



t 



}ia 



upon 
may 

inents < 

< 

rienee i 

it If 

substan 

would 1 
genera] 



inmera 



eonditi 



circnra 



cryst 



ui 




amera 



same 



6 



each 

well 



ral 



ii 



n 



vein 



lion of 



no 



' Sim 



This ic 



'-\ti i 



1 



cl ■ 



H^, 



■'?: 



til 



-i^'i 



•f 



\ 






t 



+ 



U 



<^c 



r. 






tff^ 



I' 



b 



l*^ 



J 




Sect. VIII.] 



MINERALOGY. 



237 



sketched in most treatises on mineralogy, and works have 

been dedicated solely to it. 

Experiments in the laboratory have pointed out, what 
the m;)de of occurrence of natural minerals would have 



of 



led us to expect, that the multiplied modifications 
some primary or fundamental form observed, much depend 
upon the conditions under which inorganic substances 
may have crystallized. So long ago as 1788 the experi- 
ments of Leblanc showed this, and the every-day expe- 
rience in laboratories and chemical manufactories proves 
it. If by accident or design a solution of some given 



substance be added to another, the crystals of that which 
would be otherwise formed from the first solution become 
modified in shape : all the crystals so produced being 
generally similar. Thus also in nature, all collector? of 
minerals know that certain localities, in other words, giTcn 
conditions arising from the combination of rocks and other 

r ^^^ 

circumstances where the minerals arc found, produce 
crystals of some substance with a marked crystalline 
exterior, so that not unfrequently it is not difficult for a 
mineralogist, when differently modified crystals of the 
same substance are before him, to point out from whence 



each may have been obtained. Again^ 



mineralogists are 



well aware that some mine, or in other words, some mine- 
ral vein, or part of a mineral vein^ will afford a modifica- 
tion of a known mineral most abundantly for a time, and 
no similar modification be afterwards discovered in it. 
This is but the result of certain conditions, which have 
obtained in the particular cavity of the crack in the en- 
closing rocks, and v*hich otherwise variously filled consti- 
tutes the vein. 



P r. 










I 






i 



^ 



238 



MINEllALOG Y. 



[Sect. VIII. 



Althou 



o 



under wliich they may be formed, it is found that many 
substances will bear an admixture, sometimes consider- 
able, of other substances, without having their power to 
crystallize in certain fundamental forms prevented, the 
particles of the one substance, as it were, compelling 
those of the other to adjust themselves in a subordinate 
manner to them. This is more especially the case where 
the admixture is clearly mechanical, as regards the sub- 
stance so compelled to adjust its particles that they do 
not interfere with the fundamental or primary form of 
crystal of the more powerful body. Of this one of the 
most marked is the well-known crystallized sandstone, as 
it is often termed, of Fontaincbleau, where grains of sili- 



ceous sand are gathered up by crystals of carbonate of 



lime, and do not injure the form of the latter. It is not 
im.probable that the matter found in many minerals, and 
considered extraneous, may often thus be mechanically 
mixed. However this may be, the proportions in which 
one substance may be sometimes mingled with another, 
the crystallization obtained being that proper to the minor 
quantity (as if though less in that respect it was greater 



in crystalline power) 



are very remarkable. 



M 



Beudaut was enabled to produce crystals of the form of 
sulphate of iron which contained 85 per cent, of sulphate 
of zinc, the remainder only (15 per cent.) being composed 
of the substance which gave the form to the crystals.* 

With regard to dimorphism, or the crystallization of 
the same chemically composed substance in two distinct 
forms, considered fundamentally different, we have 

* Beudaut, ' Annales des Mines ' (1817), tome ii . p. 10. 



**'" 



ai 



f 



\^ 



-^M 






^ 



s 



% 



parti-- 
:ith the 

crystals 

sun, wc" 
t]]rou,?li 



1 . * " '" 



its first . 



nerals hi 



fomi': ED 

'>'Ji the 
foiin.t 

With 

hy anc .' 



as befi 



when 



0] 



nesia, 11 
thu 



- r. 



crystals 

belong j 



Pi'eseiiti 
pear u 



E 










! 



*s; 



^H. 



n 






f 



t. 



I 




I 



I 



w 



1 ! 




I 



» i 




If 



>^ « 



r 



*f 



f 



Sect. VIIL] 



MINERALOGY. 



239 



this 



pro 



already remarked that carhonate of lime has 

perty, and that a difference in the heat of the solution 



whence it raa^ 



formed 



to accompany this 



variation of shape. This apparent influence of difference 
in temperature upon the arrangement of the component 
particles becomes the more interesting when we couple it 



with the experiments of Mitscherlich.* Right rhomboidal 
crystals of sulphate of nickel exposed in a vase to the 
sun, were found changed in the interior, without passing 
through the liquid state, into octahedrons with a square 
base, the exterior crust of the original crystals retaining 
its first form. As previously observed, the natural mi- 
nerals hitherto ascertained to have two different primitive 
forms amount to so few as scarcely to interfere materially 
with the determination of minerals by their crystalline 

form.t 

With isomorphism^ or the replacement of one substance 

by another, so that the resulting crystals are not altered, 



as before stated, the voyager will not be embarrassed 



when he becomes familiar with such substances. 



Mag- 



nesia, lime, protoxide of iron, and protoxide of manganese 
thus replace each other in any proportion. With the 
crystals termed pseudomorphotis^ or those which do not 
belong to the chemical character of the substance thus 
presenting them, the case is different. There would ap- 
pear two classes of these bodies ; at least it is convenient 

4 

"^ Mitscherlich, ' Annales de Chimie et de Physique/ tome xxxvii 
t M. Dufrenoy points out that the two forms of carbonate of lime, 
carbonate of iron, and carbonate of lead are of the same nature, aU 
occurring both as vhombohedrons and as right rhomboidal prisms, and 
adverts to the probability of the carbonates of baryta and of strontia 
being dimorphous also. ' Traite de Mineralogie/ tome i. p. 204. 



;vi^ 







H^." 



T-^ 



^' 






\ 




^* 








240 



MINERALOGY. 



[Sect. VIII, 



in our present state of knowledge so to divide them. The 
fiFst class shows the mere filling of a mould, left by the 
disappearance of one mineral, with the matter of another 
of dissimilar chemical composition, and which, if it could 
have crystallized out freely in a cavity, or amid yieldin*^ 



a change of conditions took 



particles of matter, w^ould also have had a dissimilar ex- 
ternal form. The study of the minerals forming the 
substances which have filled up the cracks or dislocations 
in rocks, commonly known as mineral veins, or fault>, as 
they may or may not contain ores of the useful metals, 
abundantly shows us that, after the formation in them of 
some crystallized minerals, and the envelopment of these 
by another mineral substance, 
place in the crack or fissure, in such cases only partially 
filled wdth solid matter, so that the original crystals were 
removed. It is again obvious that while the cavities left 
by these crystals continued empty, or formed little hol- 
low^s in which minerals of various kinds have merely 
covered the sides, partly filling these hollows, at others 
some given mineral has completely occupied the cavities, 
so that while internally keeping the structure peculiar to 
it, the exterior form corresponds exactly with that of the 
original and removed crystal. Further observation shows 
us that while in the greater number of instances the mine- 
ral substance forming the mould has remained firm, fre- 



quently covered over by other mineral substances, depo- 
sited from variable solutions in the crack or fissure until 
this bo finally and completely filled with solid matter ; 
sometimes the mould has been dissolved and removed, the 
pseudomorphous or externally false-shaped crystals ap- 
pearing uncovered and by them.selves. At least they so 



t 



Se«^ 



fill. 



,01^ 



re 



those 



5 



cba 



-A'l',. 



ar 



J 



■^n. 



'0^ 



were, <^' 
clialcedon 



h 



-1^1 other 
tl . fill 



15; 



vt '■\r. 



i 



S 



ucn a^ . 



•1 



minerak : 
those cl(=^n 



and tbr 



'^\^ 



parati^'^ 

'm of ^ 



tliat 



W. 



we^ 



- 1] 

^ par- 



1 ^^-jji ^ 



> 



1 



HMf 




t» 



Ti« -i 



^n^ 




\ 





r 



r 







. V 



I < . 



IS 



yi 




J 



? 



u 



<»T 



4 

* 



i 

r« 



r«ii^ 



I 



* 




I 



t. 



J 






*• 



^ 



ig^. 



Sect. VIIL] 



MINERALOGY, 




41 



remain, if not again covered in consequence of any of 
those changes which may have taken place in the mineral 
vein, and by which new mineral matter may be thrown 
down, being of com^se liable, like any other of the pre- 
existing minerals, to be covered up by deposits of this 
kind. As might be expected, the minerals thus, as it 
were, cast in a mould, vary conblderably ; silica, often as 
chalcedony, being in some districts frequent 

When we find the hollows that have been left in rocks 
by the disappearance of the original substances of shells, 
and other organic remains which have been entombed in 
them, filled by various mineral substances, some totally 
different from the original matter of the organic remain, 
such as silica, and the sulphurets of iron, copper, and lead 



pseudomorph 






minerals in the body of a rock itself. In spring waters^ 
those clearly derived from rain percolating through rocks, 
and thrown out on the sides of hills by some bed called 
impervious, a term which should be only regarded as com- 
parative, we find abundant evidence of the chemical solu- 
tion of some parts of the beds which the water has passed 



through. 



In all kinds of 



s 



;h 



in volcanic countries rnay be regarded as w^ater formed by 
the condensation of steam, we still find the same thing, so 
that we are prepared for the filling up of hollows and 
cavities, no matter how formed, by matter brought in 
solution into them, and partly or wholly left there, ac- 
cording to circumstances. Of this kind of filling up, the 
vesicles and gas, vapour, or air-cavities of igneous rocks 
of different geological ages afford us excellent examples, 
more particularly when it is seen, as it often can be, that 

M 






I 



^ 






^ 



-J- 



-3 



Ti 



-^ 



-2 



-T 



X - 



-iiij 



3 
I 





242 



MINERALOGY. 



[Sect. Vlil. 



at one time the elements of some mineral substances have 
succeeded to others in percolating into, and being depo- 
sited in these hollows or cavities. If a crystal of any sub- 
stance, such as felspar, disappears in the body of a rock, 
leaving its mould, any mineral substance entering the 
hollow may take its form, as is the case with the well- 
known pseudomorphous crystals of peroxide of tin from 

jies, Cornwall, the peroxide of tin having thus filled 
cavities left by felspar crystals. The other class of pseu- 
domorphous minerals would appear to have been formed 
in a different manner, there being little reason to suppose 
that like the pseudomorphous minerals before mentioned 
they have merely filled up moulds left by the disappear- 
ance of the original minerals. On the contrary, the 



elements of the new mineral seem gradually, molecule by 



molecule, to have replaced the old mineral, so that the 
original form is always retained. At first sight, perhaps, 
this kind of replacement may be difficult to conceive, but 
when we learn that a plate of steel was found in part 
replaced by silver, having been left eight years in a case 
at the mint in Paris, in contact, by one of its ends, with a 
solution of nitrate of silver, which reached it slowly from 
a fissure in the yessel containing the solution, this difficulty 
vanishes. Now and then specimens are found wherein 
the parts of the original crystals still occur, ^he remainder 
replaced by another substance. 

By a careful consideration of these exceptions to the 
agreement between the external forms of minerals with 
their composition, v.hloh are by no means so formidable 
when we regard the subject as a whole, the voyager may 
derive most important aid in the determination of the 



\ 






c 






gect' 



s 



1 



cry 

font 

any 
stru 

reqi 
babi 

ele: 



s 



sina 
clea 

isr 

crysl 

the 

resea 

c!ea\ 

const 

cryst 

plani 

for 

clea 
terrn 



\ 



und. 

>ng is 



that 



( 



With 



F 



I. 



i_ 



1 
li. if 






-< 



Sect. VIIL] 



MINERALOGY. 



243 



r ^ 






tA 



m 



} 



I 



' ft 




\^ 



i 



e\\ 



m 



m 



§ 



{. 



i 



rtltl 



r 



i 







1 



.# 




1^ 




f 



% 



c 



I- 







m 






5 



crystallized minerals he may collect from their crystalline 



forms. 

To cleave minerals, so as to acquire a knowledge of 
any form made thereby apparent, thus exposing a 
structure aiding in the determination of the mineral, 
requires both dexterity and a fair knowled^ 
bable planes of cleavage. While some minerals, like 
selenite, cleave most readily, in others it is only by a 
smart blow upon a chisel, placed in the supposed lines of 
cleavage, that this is eifected. In others, again, cleavage 



is more to be traced by lines observed on the faces of the 
crystals than to be obtained mechanically. In some again 
the structure can only be traced by means of optical 
researches. It is found that in the same mineral the 
cleavages are always disposed in the same manner, forming 
constant angles with each other, and w ith the faces of the 
crystal When there are three directions of the clea 
planes, the resulting solid always presents the same angles 



^•r 



agre 







for the same kind of mineral. W 



the planes o 



f 



cleavage are in more than three directions, one set is 
termed principal, the other supplementary cleavages. 

The crystalline types, as they have been termed, those 
under which the difterent forms can be classified, h 



H 



ave 



been variously treated by crystallographers. The follow- 
ing is the arrangement adopted by Dufrenoy, founded on 
that of Haiiy : 






regii 



With perpendicular axes : 

I. Cube. 

rbomboidal dodecahedron, the hexatetrahedron, the trapezoi- 
hedron, the octotriahedron, and some other forms. 

II. Right prism with a square base.-The modifications of Trhich are 

the octahedron with a square base, the dioctahedron, and others. 

m2 



244 



MINERALOGY 



[Sect, VIIL 



lit. Right rectangular pristn 



The 



-.1 



prism, the rectangular octahedron, the rhom 



right rhomboid 
boidal octahedron, &c. 

With oblique axes : 

IV. Rhomhohedron. — Tncluding equiaxial rhcmbohedrons, scalene tri- 
ano-ular dodecahedrons, two regular prisms with six faces, aud 
isosceles triangular dodecahedrons. 

V. Ohlique rhomboidal prism.—Wiih its modifications. 



Ncn 



With its modifications. 



Instruineiits, named goniometers^ have been invented 
to measure the angles made by the different planes of the 
crvstals, as well those considered primary as their modi- 
fications. The most simple is that of ITaiiy, consisting of 
a graduated semicircle, %yith metallic adjustments, so that 
by applying these adjustments the angle sought is read 



-1 



off upon the graduated semicircle. This was found a 
somewhat rough process in many cases, and Wullaston 
invented his reflective goniometer, by means of which 
adjustments are applied so that the bright surfaces of 
the crysta^Uine planes are made to coincide with them. 



and the angles 



are 



thus closelv read off 



This go- 



niometer being inapplicable to crystals, the surfaces of 



which are not 



:ht 



constructed by M, Adelmann, by which both methods 

employed, as the cases for their use in preference 






mav arise- WoUaston s goniometer is a very valuable 



instrument, and 



« 



A 



^ There are boxes containing the models of crystals, one of which 
(for thej occupy little space, and could readily be put away in a berth or 
cabin^ might be found very convenient for the voyager desirous of avail- 
ing himself of the external characters of minerals for their determina- 
tion. The number of models in these boxes varies, but most of them 



con tarn 



the crystalline types according to some system, their chief 



modifications not uufrequently having the names of some characteristic 
minerals upon them. 



I 



t 



Sect' 



very 

Pr- 
It 

ofSc 
acq! 

ofi 
al 



(|U 



shot: 



witb 



c 



F 



ben 






« ( 



Qualil 







o*^^ 



ai 



Aii 



Up Ti 

vary ' 

about 

ail wt 



the 



Ul 



mstru 
dry St 

Moi 

^aliu; 

to be 

tijllnrw- 



Use 



-»as 



andr 



V4. 



of 



> \ 



. ^1 

"delude 



X. 



y. 



^ 




lb 



I 



A 



ir 



I 



n" • 




fe* 



t ^ 



1 * 

• 



. I 







k 



I' 




B 



H!^ 



P 

1^ 




iiB 



. 1 




Sect. VIII.] 



MINERALOGY. 



245 




very simple goniometer has also been constructed 

Dr» Leeson.* 

It Is probable that to chemical composition th- voyager 
will chiefly look for aid, more especially if he be a medical 
officer, and therefore likely to have become sufficiently 

V 



-r 

acquainted with chemistry for the purpose. The modes 
of investigation will readily present themselves to one so 
qualified,! and we would suggest that no surveying voyage 
should be sent, more particularly to distant countries, 



for 



without one of those little chests of needful things 
chemical research which are prepared for the purpose4 
For those not sufficiently versed in chemistry it might be 



* < 



Memoirs of the Chemical Society/ vol. iii. p. 486. 



t The following works will be found useful :— Will's * Outlines of 
Qualitative Analysis/ Fresenius's 'Qualltatiye and Quantitative Ana- 
lysis/ ParnelFs 'Qualitative and Quantitative Analysis/' and Eose's 
'Analysis/ translated by Normandy, 

X Griffin (of Glasgow, and of Baker Street, London) and ethers fit 
up \-ery compact and useful chests of this kind. They necessarily 
vary m price according to their contents. For about 8Z., a chest of 
about 1^ cubic feet, not a cumbrous size for a cabin, may be obtained. 
It would contain apparatus and substances sufficient for discriminating 
all well-known ores and minerals, including a blowpipe apparatus with 
the necessary fluxes and reagents, as also a selection of the most useful 
instruments for testing in the wet way, with a collection of tests in the 
dry state, and stoppered bottles to contain solutions ; also a set of bottles 
with pure acids. 

More complete chests may be obtained for about 15/. or 16/. — far more 
vahiable for long voyages, during which deficiencies cannot be expected 
to be supplied. These are divided into two chests, one containing the 
things needful for more constant, the other large articles for occasional 
use, as well as duplicates of apparatus liable to be broken, with an extra 
s^tock of chemicals. These chests usually occupy about 4 cubic feet, 
and contain apparatus and chemicals sufficient for the complete quan- 
titative analyses of minerals, or the separation of the component parts 
of a mineral, in quantities sufficient for an accurate analysis. They 
include platinum crucibles, Bohemian test tubes, Berlin porcelain 
crucibles and capsules, complete blowpipe apparatus, &c. &c. 






te 



^^ 



(^ 



\ 



^ 



n 



i 



2U 



MINEKAIX)GY. 



[Sect. VIII. 



St' 



^ 

hazardous to attempt the wet method of investigatioiu but 
by a little practice, much knowledge may be acquired by 
the blowpipe, or what may be termed the dry method. 
Works are especially dedicated to this mode of inv 



stiga- 



tion. As these may not be at hand, Mr. Warinoton 
Smjth, Mining Geologist of the Geological Survey of the 
United Kingdom, and who has long employed the blow- 
pipe in his researches, has prepared the following short 
notice of the mode in which this instrument may be ren- 
dered useful : 

The ordinary blowpipe is so well known as scarcely to need descrip- 
tion, Varioiis forms have been recommended by their inventors, but 
for common purposes it is only important that the orlSce be not too large, 
and that the tube be provided with a reservoir for the reception of the 
moisture which is carried into it with the breath. The flame of a neatly 
tninmedlamp is undoubtedly the most convenient, but that of a common 
candle is quite applicabk to the qualitative tests with which we shall 
have occasion to deaL 

In looking at the flame of a candle, we may observe two principal 
divisionsj which it is necessary by the assistance of the blowpipe to use 
separately, since their action on the same substances is so different, as on 
the one hand greatly to facilitate certain processes of analysis, and on 
the other to cause much perplexity unless clearly understood. 




B 




! 



The outer and larger part of the flame c, d, e, which is the source of 
its light, is caused by the full combustion of the gases derived from the 
oil, wax, or tallow which rises into the wick, and is called the reducing 



flur 
the 

Tl 

iifl 
da 



* 



ex 

re* 



A- 



A- 



r 



wh 



uni 



i 



ing 



am 

sul 
tici 
mc 
cir 



4 



4 

oxi 

sou 

6 

and 

7 
com 

8 
1( 

1] 









i 



^ 



4 «. 




. i 



-t* -. 



< 



i 





B 




J I. 



iP 






Sect VIIL] 



MINEHALOGY 



247 



flame, because when concentrated upon the substance to be tested, M tends 
to abstract oxygen from it and thus to reduce it. In the lower part of 
the flame a narrow stripe of deep blue may \ ' observed, b, c, which when 
acted on by the current of air from the blowpipe forms a cone, 6, c (B). 
This is technically called the oxidizing flmne, from its property of 
imparting oxygen to the substance upon which it is directed. To pro* 
duce the latter, the point or jet of the blowpipe should be il ned into 
about a third of the flame, and the assay is then to be held at Ae 
extremity of the cone of blue flame. For reduction the point of the 
tube should scarcely penetrate the flame, and the assay should be so 
placed as to be completely enveloped in it, and thus prevented from 

receiving oxygen. 

A little practice is sufficient to overcome tlie slight difficulty which at 

first is felt in keeping up a continual and even stream of air. The tyro 
may begin by accustoming himself to breathe through the nostrils 
whilst his cheeks are inflated, and will soon find it easy to maintain an 
uninterrupted supply for several minutes. 

Of the instruments used in experimenting by the blowpipe, the follow- 
ing are the most necessary ; — 1st. A pair of fine-pointed forceps, tipped 
with platinum. 2nd, A small spoon of platinum. 3rd. An agate pestle 
and mortar. 4th. Thia platinum w-ire and holder. 5th. A magnet, 
6th, A few small tubes of thin glass. 7th. Some small porcelain cap- 
sules or saucers. Charcoal is required as a support in many eases, par- 
ticularly in the reduction of ores 5 and the following re-agents are also 



under 



circumstances : 



1st, Soda, or carbonate of soda, 

2nd. Borax, or borate of soda, 

3rd. Microcosmic salt, or phosphate of soda and ammonia. 

4th, Saltpetre, to increase the degree of oxidation of certain metallic 

F 

oxides. 

5th. Bovax-glass, for the determination of phosphoric acid, and of 
small quantities of lead in copper. 

6th. Nitrate of cobalt, in solution, to distinguish alumina, 
and oxide of zinc. 

7 th, Oxide of copper, for dr' rmining small quantities of chlorine in 

compounds. 

of lithia, boracic acid, and gypstim. 




9th. Lead in a pure metallic state. 
10th. Bone-ashes (9th and 10th are used for separating the silver from 
certain argentiferous ores). 

11th, 12th, and 13th. Hydrochloric, sulphuric, and nitric acids. 



? 



\ 

i 






i 



i 






t.- 



\ 



248 



MINERALOGY. 



[Sect. VIII. 



Se^ 



1 



f 



i 



^- ■> 



Hth. LitmuS'paper, blue and red, for detecting the presence of acids 
aud alkalies. 

The experiments on an unknown mineral mast be made systematicalh 
and referred for comparison to some list or table of minerals in ■which 
their behaviour before the blowpipe is described, as VonKobell's tables.* 

The first point to examine is, whether it be fusible; and if so, in what 



degree. The various grades of fusibility may be conveniently divided 
into six ; as representatives of which it is convenient to take the follow- 
ing minerals^ species which are everywhere easy to obtain, and which 
may therefore be often practised upon ; 

1. Antimony-glance^ or snlphuret of antimony, which melts at the 

caddie, 

2. Natrolite, or mesotype, jBne splinters of which may be rounded 

by the candle-flame, 

3. Aimandine, or precious garnet, which fuses in large pieces before 

the blowpipe, 

4. Actinolite (hornblende), fusible only in smaller portions. 

5. Orthoclase (felspar) offers some difficulty ; and 

6. Bronzite can only be rounded by the flame in the finest splinters. 

According to this scale, the mineral in question may be referred to 
either of the above numbers, or placed half-way between any two of 
them ; as for instance, apophyllite, being more easily fused than natrolite, 
and yet more refractory than antimony-glance, will have its comparative 
fusibility represented by 1 '5. 

The fragment to be experimented upon is generally held in the pla- 
tinum forceps, but it is necessary to guard against the melting of the test 
upon the points, since the platinum, though infusible, is by that means 
rendered brittle. 

In other cases the mineral may be supported upon charcoal ; but what- 
ever be the means of holding it^ the phenomena exhibited by the action 
of the flame must be noted, as 

Ut. The manner in which it fuses, whether quietly, or with decre- 
pitation, exfoliation^ intumescence, or phosphorescence ; whether it loses 
or retains colour and transparency. 

2nd. The appearance of the product, whether a glass, an ena7nel, or a 
dag ; or, as in the case of ores reduced upon charcoal, a metallic bead 

or reoidus, 

3rd. The separation of volatile substances, and the colour of the 
deposit on the charcoal, by which we may recognise 



* Yon Kobell, ' Tafcln zur Bestimmung der Mineraliea, Miinchen, 
and the same translated into English by K Campbell. 



f 






i 



4t 

dire( 



redy 






1^ 



Tl 
plati] 

Jaine: 
the f( 



. 1 



c 



Ox 



It 



0.: 

Ox 



-* 



i 

L 

I 



I 





^W 







p* 



Sect. VIII.j 



MINERALOGY. 



04q 



«. Lead, giving a greenish yellow deposit. 

b. Zinc, having a white crust, which when heated becomes yellow- 

ish and difficult to volatilize. 

c. Antimony, a white deposit, easy to volatilize. 

d. Bismuth, a crust partly white, partly orange-yellow, without 

colouring the flame. 

e. Sulphur, with the well-known odonr of sulphurous aci(i 

/. Selenium, in an open glass tube, gives a red deposit «rf selenium. 
g. Tellurium, in a similar glass tube^ gives a grayish-white erust of 

its oxide. 
A. Arsenic gives off a grajish-white vapour, which 

garlic. 
I. Quicksilver, in a^ glass tube, will be pi^cipitated^ in minute 

metallic globules. 
k. Water, from hydrous minerals, deposited by condensation in the 



sanells 



same manner. 



flame 



4. 

directed upon the mineral ; whence may be distinguished 

a. Ked tint, given by several minerals contaiping strontia and 

(?) lithium. 

b. Green, produced by soiue phosphates and borates, sulphate of 



c. 



baryta, some copper ores and tellurium ores. 
Blue, given by chloride of copper,, chloride of lead, &c. 



5th. The development of magnetic properties after treatment in the 
reducing-flame, as in ores of iron, nickel, and cobalt. 

So far the assay has been considered by itself; bttt it is frequently 
necessary to mix it with fluxes, either to render it fusible or to produc- 
a glassy compound of a characteristic colour. 

Thus if boras or microcosmic salt be fused into a glass at the end of a 
platinum wire bent into an eye, and a little powder of the unknown 
mineral be added to it, we shall obtain by the use of the oxidizing fi 

the following results : 

Manganese, in all its compounds, gives a beautiful jiolet or amethyst 

colour. 

Cobalt causes a sapphire-blue colonr ; chromium an emerald-green. 

Oxide of iron produces a yellowish-red glass, which becomes paler as 
it cools, and at length grows yellow or disappears, 

Oxide of cerium gives a red or dark-yellow colour, which ako grows 
paler as it cools. 

Oxide of nickel renders the glass a brown or violet tint, which after 
cooling becomes reddish-^brown, 

m3 ; 



^' 




. ^^r 




3? 




m. 




a^" 








[ 






*^: 








h B 



250 



MINERALOGY. 



[Sect VIII. 



Oxide of copper in very small quantity giTes a green tint, -which 
grows blue in cooling. 

Oxide of uranium renders the glass bright-yellow, which in cooling 
takes a greenish tint. 

Oxide of antimony gives a pale yellow colour, which soon disappears. 

When soda is used as a finXj it is generally upon charcoal, and by this 
aid the metals may be obtained from most of their combinations in a 
pure state. For this purpose the powdered ore is either mixed with the 

dstened soda in a paste, or is enveloped in a piece of thin paper which 
has been dipped in a solution of soda. After fusion, that portion of the 
charcoal which has absorbed any of the fluid substance is to be cut off 
and ground down with it in the mortar, when the metal, if malleable 
will at once be recognised. If several metals are combined, of which 
one is more easily oxidized than another, as for instance lead when 
eombhied with silver or copper, the latter maybe separated by adding 
metallic lead or boracic acid, according to circumstances, and main- 
taining a continued oxidizing flame, till the whole of the lead has 
passed into the state of litharge.* 

We will now suppose the voyager landing upon some 
coastj and desirous, among other things, either of adding 
to our knowledge of minerals or their localities, or of dis- 



covering ores of the useful metals or coaL With respect to 



many minerals and the ores of the metals, it fortunately 
so happens that precisely the same places may be searched, 
and these are cracks and fissures, or those dislocations of 
rocks known as faults, either partially or wholly filled 
with mineral matter. Should he see before him such veins 



as a and b traversing the rocks of a cliff, he should not 



neglect to land there. If any hollow spaces present them- 

let him there search for the crystalline minerals. 



. - 1 < . ■ 



* By means of more complete apparatus and extended operations, the 
mosrexact assays may be undertaken with the blowpipe; and those who 
desire a farther insight into the subject may consult Plattner's 'Art of 
Assaying by the Blowpipe ;' Berzelius 'Oa the Blowpipe;' and the above- 
mentioned work by Von Kobeil of Miinich,— all of which are translated 
int English. 






\ 



I 



I 



X 



bo 



Su 



i 



^' 



? 



Sect VIIL] 



MINERALOGY 





1 



I 



I 

n 



ix 






t 

1^- 



Jti 




X 






K 






••«-'• 



The vein a is represented as 



having brought different rocks into contact ; and we may 




^, J 



suppose, for illustration, that c is porphyry, and d some 
schistose rock. The fissure b is intended to he a mere crack. 
Often when dissimilar rocks are brought into contact, mine- 
ral substances are found in the fissures, and this is a point 



which the voyager should not neglect. In certain coun- 
tries the occurrence of the ores of the useful metals is 
not unfrequent under such conditions. On tidal coasts, 
should a vein of this kind be found productive, it may be 
desirable to wait for low water to trace the direction of 
the vein among any ledges or rocks which may be then 



.J 



laid bare. Tliis 



the run of the yein inland 



but not with certainty ; for though fissures or faults may 
take general lines on the large scale, they, as would be 
expected, are very irregular for minor distances. 

Should crystals be found in any such vein, it is often 
desirable to ascertain how they occur relatiyely to other 
bodies, crystalline or otherwise, ^liole groups of 
crystals are thus frequently seen placed on certain pro- 
jecting surfaces, facing one direction, and this as well 



as 



sides of the vein, or tvalls^ as they are technically termed. 



as 




^-^a '^^':=V^ :s_;^ 



252 



MINERALOGY. 



[Sect. VIII. 



^ 



4 

coniuion terms, may be called a horizoutal as a vertical 
manner. They are not due to the drippings of water 
charged with the matter of the minerals in solution, such 
as are often seen in fissares, the resulting deposits beip<y 
more or less crystalline according to conditions ; on the 
contrary, the particular modes of occurrence to which we 
allude, seem more the result of crystalline deposits from 



ons (fil 








so acted upon, that projections in a given line, more es- 



■^ 

r 



pecially if composed of certain substances, received these 
deposits — in fact much in tlie same manner as substances 
in solution may be thrown down by well-known methods 
when galvanic action is employed. We have before us 



an illustrative specimen from the Consols Mine, Gwennap, 
Cornwall, in which large crystals of quartz are on the 
one side covered by crystals of sulphnret of iron, and on 
the other by crystals of copper pyrites. Cases where 
crystals of one substance abundantly occur on one side of 
prior-formed crystals of another substance, and not on the 
reverse or opposite sides, are sufficiently common, and best 
seen in the fissures or mineral veins themselves. 

Although when exposed to the action of weather, the 
minerals which may be found in veins or fissures, open on 
the feces of cliffs, are not very often (except when of sub- 
not easily injured) in a good state of preservation, 
they show that such minerals are found in the vein, so 
that if time and opportunity permit, some unexposed part 
of the vein may be broken into. Success may not, cer- 
tainly, always attend such a search, for it is curious to 





H iL 




rve how very locaL even in the same vein, the occur- 



rence of a particular mineral may be* 



i 



I 

i 






\r 



I 



th 

It 

ob 
of 



tlit 



^L 



up 



V(, . 



t 



u 



n 



sta 




ad 

fin 

roi 

dr. 

lat 
h 



fr 



u 



c 



SO] 



fi 



SJ 



of 



f- 






« 



f 



t . 



P 



I 

I 





ft 

t 



Sect. VIII.] 



MINERALOGY, 



253 



I 






1 collecting mmerals in a vein, should a boat be 
hand, so that they may he readily taken to the ship, it 
is better not to Hmit the specimen to some mere crystal 
itself, but to break off some of the body (either part of 
the vein or of the rock, as the case may be) upon which 
it has been formed, so that when more leisure may be 
obtained, any illustration the whole specimen may afford 
of the manner in which the mineral may have been formed, 



should be preserved. By such specimens we often learn 
the history, as it were, of the mineral accumulations 
which, taken together, may, wholly or in part, have filled 
up a fissure. Tn this way it may often be seen that crys- 
talline coatings of many substances have successively co- 
vered each other up towards the centre of the fissures. 



The contents of veins are far often from heir 




defi- 



nitely crystalline ; thus qiiartz and other mineral sub- 
stances, such as the ores of many metals, have an amor- 



phous appearance, their deposit having been effected 



under conditions which did not permit their particlefe to 
adjust themselves in definite crystalline forms. 



A-gain we 



find that, during the filling up of veins, fragments of 
rocks from the sides or upper parts of the fissure have 
dropped in ; by their want of contact and by their iso- 
lation in many parts 



of the vein sliowlng that 



thl 



happened when the mineral or minerals thrown do^vn 



from solutions were accumulating. 



A 



mm 



era! 



3f- 



vein 



sometimes forms a complete breccia, and this as well 
from the cause just assigned as from the mere filling up 





of the chinks left by fragments from the adjoinin 
accumulated in the fissure before any deposit of minc.dl 
matter from solutions was effected. As might be ex- 



M 



k 



-. — ''^ - 






t 



254 



MIXERALOGY. 



[Sect VIII. 



pected, both varieties are to be sometimes seen in the 

Ores of the useful metals, such as sulphuret 



same vein 



of lead, copper pyrites, and peroxide of tin, may, and do, 
as well form the cementing matter of such fragments, as 



common quartz, carbonate of liiaej or other minerals. 
In collecting some minerals which have covered others, it 
may be frequently desirable to obtain enough of the first 
to show how the latter may have occurred. Rock crystals 
are thus often seen investing other minerals, the most 
delicate threads of the latter being preserved in them. 
By a little care we may take out enough of the crystals 
to show completely how these threads may have radiated 
from a centre or have been otherwise disposed. 

As with other mineral substances, we find that ores of 
the useful metals have been sometimes thrown down in a 
fissure at one time and not at another, the deposit of one 
ore sometimes repeated, at others not. Thus there may 



have been a coating of a zinc ore at one time, of copper 



ore at another, and a covering of tin ore upon these, 



sor^^ 



ilXC 



times separated 




other mineral substances, at 



others in deposits one above the other. Again, we find, 
in the successive dislocations which are sometimes seen 
to have effected the lines of fissures, that while the 
lines of least resistance to the applied force have been 
chiefly through the contents of the original fissure, occa- 
sionally a new fissure has been made through portions 
of the adjoining rock ; so that the minerals which may 
have been subsequently deposited in the new crack or 
fissure will be partly in the old line, and partly amid the 
newly "broken ^vid adjacent rocks. 

It would be out of place to attempt a general notice of 



r 



1 



F 



k 



i 



r 

i 







I 



^ 



i 



» 




I 





4t 





I 



Sect. VIII. 1 



MINERALOGY, 



255 



contain 



useful metals, are commonly termed mineral : it will be 
sufficient to observe that from decomposition the upper 
or exposed parts of many do not show the ores in the 
manner tl;ey occur beneath. Thus, above veins v/herein 
the ore from which the largest amount of copper is pro- 
duced, namely the compound of copper, iron, and sulphur 



as 



often found, known by many of our miners as gossan, and 



n 



This is the re- 



sult of a decomposition arising from exposure to atmos- 
pheric influences of various kinds, and occasionally from 
otlier influences. It is probable that the sulphur by a union 



uric 



formed 



the copper was attacked and removed, to be 
dealt with like any other solution of sulphate of copper. 
And beneath this gossan, or the hack of the lode, as it is 
often termed, we observe appearances ctrongly reminding 
us of the common electrotype process for procuring copper 



from a similar solution. 



TI.o pure me 



tal is 




together in chinks and cavities between the main mass 
of gossan and the body of the undeconiposed copper 



occasiona 



pyrites, mingling, perhaps, 
part of the former. Sometimes this native copper, as it is 
called, may retain its metallic character, but at others it 
becomes converted into an oxide, and this again into a 
carbonate by the percolation 
air and carbonic acid. The iron seems in a great mea- 
sure to have been left behind, and this forms the rusty sub- 
stance above mentioned. It will be readilv understood that, 

•I 

tlic needful conditions obtaining, other parts of a mineral 




common 



*1 






^. 



^^. 



t 



256 



MINERALOGY 



[Sect. VIII. 



gect. 



^ 



I 

1 



i 






,"^ 



vein than tlie mere upper portion may become decomposed 
in the same manner. In fact, the changes which have been 
eiFected in the fissures containing mineral veins, the mode 



of throwing down a mineral substance, its subsequent re- 



tire 



f* 



moval^ its reappearance, or apparent transport elsewhere, 
the pseudoraorphous filling up of crystalline cavities, the 
substitution of particles of one substance for another, the 
evident alterations produced by new fissures, particularly 
W'hen these have traversed the original fissures at right 
angles, the differences of contents of fissures when they 
take different directions traversing the same country and 
association of rocks, are objects of high interest ; and 
though nc doubt best studied in mining countries, where 
opportunities are so numerous, and veins are so exten- 
sively laid open, a voyager, with some little time on a 
favourable portion of coast, may often nevertheless ac- 
quire mucli inform-ation on these heads. To do so, and 
procure illustrative specimens and a highly valuable col- 
lection, interesting in many respects, it is not necessary 
that the vein should be one containing the ores of the 



useful metals 



disloca 



tions, termed common faults, are often in a scientific 
point of view equally important- 

The cavities of many igneous rocks, and indeed holes 
and cavities in all, afford good places wherein to search 



found 



for minerals. They 
well crystallized and in good condition, from not having 
been exposed to destructive influences until the containing 
rock be broken — always, it being understood, at distances 
or depths from the surface where the atmospheric action 

may not have been much felt, or matters have entered 



■f 



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1 . fr 



su 



only 

the* 
been 

ait 

thor 



t 



I,,' 



M 

resici 



** 



befc 



the q 



1* 



to m 
Tliey 

tUDit" 

uiide 

pota 
;rea 

of V 

silic 
Inl 

off 

tinu 
of c 

ther 
to t 

SOtT' 



I 



:^».. 



1- 

r 

r 
E 

I 



f 




I 

» 




He 



h 






1 * 




<4 »^ 




r-i 



r*> 



r 



Sect %ail.] 



MINERALOGY 



257 



tlie cavities that have decomposed or Injured the mineral 

• 1 ft 



substances in them. Th 



only to the depth of a few inches, but to many feet : 
the vesicles of some igneous rocks, for example, having 
been completely emptied, near the surface, of the mineral 
matter which once filled the cavities, and which still fills 
those beneath, so that externally the rocks present much 



as 



ii 



and viscous state. 

Minerals of the zeolite family are very common in the 
vesicular canities of some igneous rocks ; and at one time, 
before their mode of occurrence was properly understood, 
the quantity of water found in many of them was thought 




Igneous 



■6 



a 



They form an interesting class of minerals, and, oppor- 



tunities offering, should always be collected. 



They come 



under the head of hydrated aluminous silicates, with 
potash, soda, lime, and their isomorphons substances. The 
great proportion of them contain from 8 to 18 per cent. 
of water in combination. In the same kind of vesicles, 
siliceous deposits in the form of agates are not uncommon. 
In these and in cavities of various rocks, even those of 
aqueous origin, such, for example, as the dolomitic rocks 
of the new red sandstone series, in Somerset and Glou 
cestershire, the agate linings of the cavities 



have con- 



tinued only for certain distances, after which the elements 
of other minerals have entered the hollows, and various 
crystallized substances have been the result. Cavities, 
therefore, in all rocks may be searched. With respect 
to the successive siliceous coatinecs forming agates, 




some kinds of coatings show an adjustment to the walls 














m 



9K\ 




MINERALOGY. 



[Sect. VIII. 



of the cavity, others have accumulated in flat layers 
generally considered to have been formed horizontally. 
Sometimes part of a cavity has been filled in one way, and 
the remaining portion in the other. Occasionally, from 

cavities left after a part of the 
hollow has been filled horizontally, 
stalactites of the matter of the 
agate have descended from above, 




IS 



as in the annexed figure. It 
desirable always to ascertain how 
far such flat layers correspond with the present horizon ; 

if the vesicles or hollows are almond-shaped (elon- 
gated more in one direction than another), how far these 






are constant in the same direction, thus pointing out that 
in which the molten viscous rock moved. 

Many nodules in rocks, those which have clearly not 
been formed as gravel or boulders by attrition, aflbrd 
examples of the aggregation of similar ma tter from a mass, 



<"> 



uch as one of day, in which that matter has once hecn 

In this way we have siliceous 



more 




iliised 




calcareous nodules, and those valuable nodules 
the clay ironstones. These last are fundamentally car- 
bonates of iron, with a variable addition of the matter of 
the mud or silt anud which the carbonate of iron has once 



been more generally diffused. 



In many such nodules 




there has been a shrinking from 
the centre to the sides, causing 
cracks, that have been va- 



riously filled with mineral mat- 



ter 



as in the subjoined figure 



Occasionally in the cracks so formed, and not quite filled 






\ 






Sect' 



Up! 



• i^« 



rtT 



tit 



blo^ 



cr) 



a 



rW \ 



1 



ore 



an 



d 



se 



/\r 



} 



ro'.x 



7 t 



to a 

roc 
or 

ha 
fer 

on 

thi 
th( 

fir 



8~ 



til 

UK 



1 




k.» > 





I 

i 
i 

i 



ti 



I 



t 



^. 



»*■ 



Sfi 



. V 



^ ^ 



Sect. VIIL] 



MINERALOGY. 





Tip, various mineral substances are obtained well crystal- 
lized. It may be here observed, as resards the metallic 



titanium frequently discovered in iron furnaces when 




blown out, that we have found the oxide of 
crystallized in the cavities of clay ironstones. Taken as 
a whole, the observer will do well to look into any cavities 
or cracks he may discover in rocks, even in the hollows 
among organic remains, for various mineral substances. 
Many a crystallized body will thus be frequently found, 
and the replacement of one substance by another be well 

seen. 

Not only in cracks or hollows, but in the body of the 

rocks themselves, minerals may be observed well crystal- 
lized, their component molecules having had free power 
to adjust them.selves according to the affinities and forms 
proper to them. This is well seen in the class of igneous 
rocks known as porphyries— that is where a general paste 
or base, confusedly crystalline, compact or earthy, may 
happen to contain isolated and well-formed minerals of dif- 
ferent kinds. From experiments in the laboratory, and the 
results of metallurgical and chemical operations carried 
on upon the large scale, we know that this isolation of 
crystals may readily be obtained, it being merely needful 



that the conditions for their production should be such that 
their component particles could freely adjust themselves 
first in the cooling mass. In the igneous dykes, as they 
are termed — that is, where igneous matter in fusion has 
been forced up, filling cracks formed in the rocks which 
they traverse — we sometimes see good illustrations of the 
mode in which isolated mineral crystals may be produced. 



T 



take as an examnle some of the granitic 



g' 



t 



• >-' 







m 



**• 



k 





i:m 



260 



MINEllALOG 



v/ 



[Sect. VIII. 






» 



known as eloans by the miners of Cornwall, and let the 
annexed figure represent a section of one of them a a 




being some schistose rock broknn through or fractured 



( 



/ c 



onsolidated : granite is 



thus frequently fractured, and the fissure filled by an 
elvan.) We find that while the central portion d may be 
a granite, the parts c c are porphyritic, and h h some com- 
pact rock. Upon investigation, we see that all parts are 
chemically th- same, and that these various characters 



are due to differences in coolin 




The central portion 



dift 



erences of 



ooling can be imitated 



retained its beat longest, while the portions adjoining the 
bounding and fractured rocks were more speedily cooled. 
In such porphyries various minerals are found, those of 
the felspar family being very common. Such results from 

artificially with 
substances under our control. In this way crystals of 
silicate of lime may be beautifully obtained, isolated in 
transparent glass. 

Whole mountain masses are occasionally composed of 
porphyritic rocks, including the porphyritic granites among 
them ; and it is desirable to obtain specimens of these, 



selecting portions where the crystals may be well formed, 



and observing, should more than one kind of isolated 
mineral be present, how far when one kind becomes com- 
mon another may disappear, and if different kmds continue 
mixed through the general m..s, or only in patches. It 



I 



I 
S 



nnl 



of*" 

beefl 






1 n 



r-T"-"?]! 



i-- 



i 



It 

onoe 
look 



• 1 



or;' 

SubSi 

by p. 

beai 

T: 

have 
oftl 

igne 

intei 

adju 

this 

of 
is 

ISO 

tio 
fro 



'^ 



s 



*^ 



'410 








I 



« 






Sect. VIIL] 



JVIINERALOGY 



261 



is equally desirable to obtain good characteristic specimens 



of 



been uninjured by exposure to the weather, and have lost 
little of the soluble substances which may have once 
been contained in the rock. 



The chemical study of th^ 



whole of such igneous rocks is every day bccomin 






more 



interesting. 



It is not only among the igneous rocks which have 



hould 



once been in a molten state that the observer 

look for minerals, but also, in volcanic regions, for those 

evidently sublimed upon the faces of craters, or in cracks 



chink 



Many 



substances thus obtained are difficult of preservation ; but 
by putting them away in bottles, well stopped, much may 

be accomplished. 

The minerals often seen isolated in those rocks which 
have been termed metamorphic, or altered, in consequence 
of the upburst or protrusion of some rock in a state of 
igneous fusion near them, constitute a class of much 
interest. Here again we see conditions well fitted to the 
adjustment of the integrant molecules of minerals ; but 
this case so far differs from that of the porphyries, that 
whereas in the latter the whole mass has evidently been in 
a fluid or viscous state, in the former the stratified cha- 
racter of the rocks of that class is preserved. The manner 
of observing this order of rocks belongs to geology, 
is only necessary here to call attention to the kind oi 
isolated minerals found. Among them staurolites, anda- 



■ 



lusites, and garnets are frequent under certain condi- 
tions, which it may be advisable to guard the observer 
from supposing merely those of temperature. The free- 




n - 







s^ 



kk 






t 



i 



t 



*^ 



^3 



262 



MINERALOGY. 



[Sect. VIII. 



dom with which the particles of the isolated minerals thus 
formed could often adjust themselves, the main mass 



We 



retaining its general structure, is liighly interesting, 
have seen crystals of garnet, perfectly formed, amid the 

contact with granite, the 



gram 



beds of the sandstone retaining their original shape, and 
the mechanically-produced grains well distinguishable. 
The component parts of andalusite have often been 
gathered together in such a manner to form that mineral 
in altered rocks, that the resulting crystals have pushed 
aside mica and other substances. 

have chiefly referred hitherto to minerals found 
crystallized, or produced under the conditions proper for 



We 



the 



e 



alone or entangling some other substances. Many im- 
portant mineral substances occur, so that, whatever may 
be the form of their ultimate molecules, they appear to us 
in mass, sometimes forming beds mingling with others, 
or occupying clefts in rocks ; occasionally constituting por- 
tions which have separated out from the bodv of the rock, 
as m the instances of the nodules previously mentioned. 
In these various form.3 many minerals are found, some 

such as iron ores, including 



being ores of the useful metals 



bog-iron among them, ard iron nv. Ites, valuable for the 
sulphur in it. As filling clefts in rocks, mingled with other 
matter, many ores of lead, tin, copper, &c. Other 



tances, also employed for various purposes, are obtained 
in the massive state, such as rock-salt, gv-psum, and coal. 
For these minerals qualitative chemical researches will 
be found valuable, it being desirable to test the com- 
position of many substances, which may offer certain 



1 



. vll 



>■ 







Aioc 



hi.-* 



i^ 



estt 

bring' 

it fS^K 



parti 



CD 



conditi 



n^'-'i 



V 




m see 

stone 

coal-l 

which 

somet 



ene" 



Lai; 

app( 

C 
silts 



^■^ii 



tersi 
occu 
not 



cas 



so 



■- _ -1- ^ 



---^.-r^^Jr- 




^ 



fr 






t, ». 



If 



i 



. « 



4^ 



Sect, VIII.] 



MINERALOGY 




g 




ven 



locality may be quitted. 



Among the minerals occurring in beds, we should more 



substances of 



that 



particularly notice coal and other 
class, which have of late become so important for the 
extension of steam navigation. Our pbipping daily 
bring home specimens of coal or lignite from localities 

And 



occur 



where they were not previously known 

it may be here needful to state, as r »w well known 



geologists, that good coal is not confined to rocks of a 



^0 



t-- 



particular geological date, but that, the needful physical 
conditions having obtained, it has been produced from 
vegetable matter accumulated at different geological times. 
When we have a cliff before us, there is little difficulty 
in seeing that a coal-bed occurs amon^ others of sand 
stone, shale, or other substances. 




N 



unfreq 
iceous 



coal-beds are based upon clays, or argilla 
which have a clayey character from exposure, and then it 
sometimes happens, from the slipping and falling of the 
general mass, that the real thickness and importance of 
a coal-bed may not appear on a cliff. Thus it was at 
Labuan, where now a valuable coal-bed about nine feet 
thick is worked : when first seen on the coast it did not 
appear more than eighteen inches thick. 

Of whatever geological age an accumulation of mud, 
silts, sands, and gravels, now more or less consolidated as 
shales, sandstones, and conglomerates, and contraning m- 
terstratified coal, may happen to have been, it rarely 
occurs that the bed upon which the coal itself reposes has 
not some peculiar character, easily observed. In many 

nasfis we feel assured that this has arisen fi'om. these beds 



f>- 



K- 







^^ 



■ V- 



/ 



H,/ 









\m 




MINERALOGY 



[Sect VIII. 



ground 



a slight covering of water, on which the plants, now con- 



verted into coal, have grown. Should these marked de- 
posits be found, they often form valuable aids in tracing 
coal-beds, where the outcrop of the latter may not be very 
apparent, and they are especially serviceable, as in many 
of the hilly coal-measure districts of the British Islands 
where these beds throw out springs of water. Whole 
lines of such springs coinciding with the bottom of coal- 



beds can be traced in 



South 



Wales and Monmouthshire, and often on a hill side 
faults traversing the general mass can be as well seen, 



where these lines are interrupted, as if a diagram section 
were before us. 

In some of the beds immediately subjacent to the coal 
peculiar fossil plants are found. In the pala^^ozoic coal 
of the British Islands a fossil plant, named Stigmaria 
ficoid.es, is very characteristic. Peculiar fossil plants, not 
the one mentioned, are discovered, it is thought, well 
marking the beds on which the coal-beds rest in the 
Burdwan coal district in India, and other instances of a 
similar kind are recorded. It will be obvious that, although 



the conditions for the production of marked accumulations 
may have preceded the growth of most of the coal-vege- 
tables themselves, the latter may not have sometimes 

so that no coal rests upon such beds, a fact 
observed, and according to conditions more in one part 




roM^n, 



of a coal district than in another. Still these beds, when 
any such occur, are useful to trace, since while we find 
in one locality no vegetable accumulation to have taken 
place upon them, or if effected the vegetable matter to 



.f n 






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111 



ofu 



U, rD 




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^fon' 



•ir-ri tb;- 



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tiift ^' 

only of 1 

assoda^ : 
be thus 



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men 



ia 






V 



Sect VIIL] 



MINERALOGY, 



2r^ *^ 
00 



*^ 





f 



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a 



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!. 



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have been subsequently removed, upon an extension of 
the same beds we may often see good workable codL 
Thouo-h in cliffs, either on the shore or on the sides of 



often 



rivers, hills, and mountains, we commonly find the 
direct evidence of the existence of coal, it may be 
traced to its beds, where such occur, by means of the 
detritus brought down by brooks and rivers. By follow- 
ing rolled pebbles up such water-courses they may be 
often seen to end near some bed or beds whence they 
have been derived. If these cross the stream, a good 
opportunity may be afforded for es:amining their quality 
and thickness. The pebbles may, however, come from 
the sides of some adjacent hills sloping towards the 



streams, the beds of coal not crossing them, fragments 



n^ 






w _ 



only of their outcrop being mingled with any others of 
associated beds. The thickness of such coal-beds may 
be thus concealed, as will be readily seen by the annexed 
section, in which a represents the river course, up which 
pebbles of coal may be traced ; b b beds of coal, the out- 
crops of which, c c, may be much concealed by fragments 




t- 




of rock descended from above and mingled in a frag- 
mentary covering d d. The best should be done to 

X 

obtain a knowledge of the associated beds by tracing up 

If 



266 



MINERALOGY. 



[Sect. VIII. 



'^ 






J 



the rills of water descendino; the sides of 




the hills. Ex- 



cellent eyiderice may thus be otten obtained, and the true 
position of the coal-beds found. In selecting specimens 



of coal in such cases, it rarely happens that a portion of 
it can be procured fairly exhibiting its qualities, injury 



having arisen from atmospheric influences. If the out- 
crop of the coal can be attained, it is always desirable to 
penetrate as far as circumstances wdll permit into the 



body of the bed, thence selecting a fair specimen. When 



this cannot be done, and a voyager often has but little 
time for his researches, fragiiierits lying about should be 
selected which may appear the least decomposed, and if 
these be different qualities, as if of portions of different 



b 



eds, they also should receive attention. 



In all cases 



wliere fossil plants are mingled with the coal or associated 
beds, specimens as various as Ian be obtained should be 
secured. These have a geological bearing which may 



often turn out of great practical importance in some 



w 



given region. 

It scarcely requires remark that the foregoing observa- 
tions are but hints which it is hoped may be useful to 
those engaged in voyages of discovery and survey, or who, 
on more general service, may feel inclined, whenever fit- 
ting opportunities may present themselves, to devote some 
portion of the time not occupied by their professional 
duties to the study of minerals, either for purely scientific 
purposes, for their useful employment, or for both com- 
bined. That these opportunities do present themselves 
we well know, or rather if sought will be found more 
frec^uently than might be imagined. Many a walk along 
a coast may thus be advantageously turned to account, 



\ 



V" 



* 




*«t 




Sect VIIL] 



MINERALOGY. 



267 



and an interest be excited not at fir-^ thought probable. 
Not only may a naval man thus add to his own stock of 
knowledge, but he may most materially by his exertions 
promote the advance of science and its applications gene- 
rally, minerals being objects of great interest, whether 



we regard them with reference to their importance to 
man, and the aid many of them afford to the spread of 
civilization, or as connected with several sciences, even 
those of the highest order. 



t- 




- + 



l.-.i* 



k2 



r J^ -X-^ ■, 



268 



[Sect. IX. 



Section IX. 



METEOEOLOGY, 



» 



By thk editor. 



There is no branch of physical science which can be 
advanced more materially by observations made during 
sea voyages than meteorology, and that for several dis- 
tinct reasons. Istly. That the number and variety of the 
disturbing influences at sea are much less than on land, 



by reason of the uniform level and homogeneous nature 
of its surface. 2ndly. Because, owing to the penetra- 
bility of water by radiant heat, and the perpetual agitation 
and intermixture of its superficial strata, its changes of 
temperature are neither so extensive nor so sudden as 
those of the land. 3rdly. Bc-^use the area of the sea so 
far exceeds that of the land, and is so infinitely more 
accessible in every part, that a much wider field of ob- 
servation is laid open, calculated thereby to afford a far 
more extensive basis for the deduction of general conclu- 
sions. 4thly. The sea being the origin from which all 
laud waters are derived, in studying the hjgrometrical 
conditions of tlie sea atmosphere, we approach the chief 
problems of hygrology in their least involved and compli- 



xed 



ate of the land (as tli( 
of deriyatiye moisture) 



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Sect. IX. J 



METEOROLOGY 



269 



agree 



as it always 






a desirable 



the notice of the meteorologist of the continents. Nor 
ought it to be left out of consideration that this, of al 
branches of physical knowledge, being that on which the 
success of voyages and the safety of voyager- are most 
immediately and unceasingly dependent, a personal in- 
terest of the most direct kind is infused into its pursuit 
at sea, greatly tending to relieve the irksomeness of con 
tinned observations, to insure precision in their registry, 
and to make their partial or complete reduction during 

the voyage an 

object. 

It happens fortunately, that almost every datuny which 

the scientific meteorologist can require is furnished in its 
best and most available state by that definite, systematic 
process, known as the " keeping a meteorological register,'' 
which consists in noting at stated liours of every day the 
readings of all the meteorological instruments at com- 
mand, as well as all such facts or indications of wind and 
weather as are susceptible of being definitely described 
and estimated without instrum.ental aid. Occasional ob- 
servations apply to occasional and remarkable phenomena, 
and are by no means to be neglected ; but it is to the 
regular meteorological register, steadily and -per sever ingly 
kept throughout the whole of every voyage, that we must looh. 
for the development of the great laws of this science. 

The following general rules and precautions are nt-ces- 
sary to be observed in keeping such a register :-^ 

1. Interruptions in the continuity of observations by 
changes of the instruments themselves, or of their adjust- 



ments, places, exposure, mode of fixing, reading, and 



t:^. 



registering, &C.5 are exceedingly objectionable, and ought 




O'T 



70 



METEOROLOGY. 



[Sect. IX. 



to be sedulously avoided 
any of these particulars 



Whenever an a 



Iterati 



ion m 



is indispensably necessary, it 



should be done as a thing of moment, with all delibera- 



tion, scrupulously noted in the registerj and the exact 

^ 

amount of change thence arising in the reading of the 
instrument (whether by alteration in its zero point, or 
otherwise) ascertained. 

2. As far as possible registers should be complete: 
but if, from unavoidable causes, bbnks occur, no attempt 
to fdl them up subsequently from general recollection, or 



f which is worse 

\ 



falsification) 



apparent course of the numbers before and after, should 
ever be made. The entries in the register made at the 
time of observation should involve no reduction or correc- 
tion of any kind, but sliould state the simple readings off 
of the several instruments, and other particulars, just as 
observed. This does not of course prevent that blank 
umns left for reduced and corrected observations 



co=^ 



1-=' 

X 



sliould be filled up at any convenient time. On the 
contrary, it is very de " " 

the sooner after the observation, consistent with due 
deliberation, the better, on every account, unless some 
datum be involved requiring subsequent discussion for 
its determination. 

3. Tlie observations of each kind should, if possible, 
all be made by one person ; but as this is often imprac- 
ticable, the deputy should be carefully instructed by his 
principal to observe in the same manner, and the latter 
should satisfy himself by comparative trials that they 
observe alike. 

4. If copies be taken of registers, they should be care- 






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Sect. IX.] 



METEOROLOGY 



271. 



■one 



fully compared with the originals by two persons 
reading aloud from the original, and the other attending 
to the copy, and then exchanging parts— a process always 
advisable when great masses of figures are required to be 

correctly copied. 

5. The registers should be regarded (if kept in pur- 
suance of orders, or under official recommendati 



) 



Xs 



official documents, and dealt with accordingly. If other- 



(tl 



^d) 



To the Secretary of, &c. &c." Circuitous 



to some public body interested in the progress of meteor- 
ological science, through some official channel, and under 

address " 

transmission hazards loss or neglect, and entails expense 

on parties not interested. 

6. The register of every instrument should be kept in 
parts of its own scale as read off ; no redaction of foreign 



measures or degre 



es 



to British being made. But it 



should of course be stated what scale is used in each. 
British observers, however, will do well to use instruments 
graduated according to British units. 

7, The regular meteorological hours are 3 a.m., 9 a.m., 
3 P.M., and 9 p.m., mean time at the place. Irksome as 
it may be to landsmen to observe at 3 a.m., the habits of 
life on shipboard render it much less difficult to secure 
this hour in a trustworthv manner ; and the value of a 
register in which it is deficient is so utterly crippledj that 
whatever care be bestowed on the other hours, it must on 
that account hold a secondary rank. The above hours, it 
must be borne in mind, are the fewest which any meteor- 
ological register pretending to completeness can embrace. 



Mfk»' 



{ 






i 



1 



272 



METEOROLOGY, 



[Sect. IX. 



By any Due, howerer, desirous 



of paying such parti- 
cular attention to this branch of science as to entitle 
him to the name of a meteorologist, a three-hourly 
register— "yiz,5 for the hours 3, 6, 9, a.m., noon ; 3, C\ 9, 
P.M., midnight — ought to be kept ; and in voyages of 
discovery, where scientific observation is a prominent 
feature, the register ought to be enlarged, so as to 
take in every odd hour of the twenty-four; thus in- 
cluding, without interpolation^ the six-hourly or standard 



series. 



8. Hourly observations should be made throughout the 
twenty-four hours on the 21st of each month (except 



when that dav fall" 



on a Sunday, and then on the 
Monday following), commencing with G a.m., and ending 



at 6 A.M. on the subsequent day, so as to make a series 
of twenty-five observations. At all events, if this cannot 
be done monthly, it ought not to be omitted in March, 
June, September, and December. Tliese are called 



" term observations/' If any remarkable progressive 
rise or fall of the barometer be observed to pervade this 
series, it will be well to continue it until the maximum 
or minimum is clearly attained, with a view to comparison 
with other similar series elsewhere obtained, and thus to 
mark the progress of the aerial wave effective in pro- 
ducing the cliftnge. These term observations should be 



separately registered under that head. 

9 J Occasional hourly series of observations may be 
made with advantage under several circumstances, as, for 
instance — Istly. "When becalmed for any length of time, 
aspecially when near the Equator, with a view to deter- 
mining the laws and epochal hours of diurnal periodicity. 



I 



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to 



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Sfecti IX.] 



METEOKOLOGY. 



273 



2ndly. When a party leaves the shi{), furnished with a 
portable barometer or other instruments, for the measure- 
ment of heights of mountains, or with other objects. Srdly. 
During threatening weather, and especially during the 
continuance of gales, and for some time after their sub- 
sidence as will be more particularly specified under the 
head of " Storm Observations." 4thly. In certain spe- 
cified localities mentioned in a subsequent article by Mr. 
Birt. 5thly. Whenever a continued rise or fall of the 
barometer has been noticed as at all remarkable, it 
should be pursued up to and past the turn, so as to 
secure the maximum elevation or depression, and the 
precise time of its occurrence ; and a register of such 



maxima or minima should be kept distinct from the 



regular entries. 



Of Meteot ological Instruments ; and first, of the Baro- 



meter and its attached Thermometer. 



Tlie 



girnbal frame, which ought not to swing too freely, but 



rather so as to deaden oscillations by some degree of 
friction. Before suspending it, it should be carefully 
examined for air-bubbles in the tube and for air in the 
upper part above the mercury, by inspection, and by 
inclining the instrument from the vertical positidn rather 
suddenly till the mercury rises to the top with a slight 
jerk, when, if it do not tap sharp, the vacuum is imper- 
fect ; and if the sound be puffy and dead, or is not heard 
at all, air exists to an objectionable extent, and must be 
got rid of by inversion and gently striking with the hand 
to drive the bubble up into the cistern. The lower end 

N 3 



m. 




274 



METEOHOLOGY. 



[Sect. IX. 






\ 



1 

of the tube, which plunges into the cistern in well-con- 
structed marine barometers, is contracted so as to diini- 

shi p's 



nisli 



the amount of oscillation produced by the 



motion. 



The instvaiiitent should be suspended out of the 
reach of sunshine, but in a good light for reading, as 
near midships, and in a place as little liable to sudden 
changes of temperature and gusts of wind as possible. 



The light should have access to the back of the tube, so 
as to allow of setting the index to have its lower edge 



mercury 



In 



a tangent to the convex surface of the 

O 

+ 

w%ll-c6nstructed harometers the slider has its lower 
p£irt tubular, embracing the tube, and can be made to 
descend by the rack-motion of the vernier till it be- 

comes an upper tangent 
being on its exact level, a reflected light by day, or 
white paper strongly illuminated from behind at night, 
will throw the light properly for setting the vernier 
correctly. The exact height of the cistern above the 



to the mercury : the eye 



■.^ 



hi 



ip 



r^ 



water-line bliould be ascertained and entered on 



tl 






register. 



The attached thermometer ought to indicate a tem- 
perature the exact mfean of that of the whole barometric 



column. Its bulb, therefore, ought to be (though it 
seldom is) so situated as UY afford the best chance of its 
doing so, that is to say, fifteen inches above the cistern, 
enclosed within the wooden case of the barometer, nearly 
in contact with its tube, and wdth a stem so long as to be 



read off at the upper leveL To ensure a fair average 
and steady temperature, it were w ell to enclose the whole 
instrument, thermometer and all, in an outer case of 
leather, over a wTapper of flannel, leaving only the scttmg 



. 



I 



Sect. I X.I 



METEOROLOGY, 



271 



» 



and reading parts above and below accessible, and that 



* 



no more than is absolutely necessary. 

In choosing a barometer, select one in preference in 
which the lower level (of the mercury in the cistern) is 
adjustable to contact with a steel or ivory fiducial point, 
and that not by altering the height of the mercurial su 
face, but by depressing the steel point carrying doion with 
it the whole divided scale, the zero-point of which is of 
course the apex of the point itself. Care should be taken 
that air have free but safe access to the lower surface. 

In transporting a compared barometer to its place of 
destination great care is necessary. Carry it upright, or 
considerably inclined, and inverted; and over all rough 
roads in the hand, to break the shocks it would otherwise 
receive. A " portable barometer " strapped obliquely 
across the shoulders of a horseman travels securely and 
well ; and with common care in this mode of transport 
its zero runs no risk of change. If merely fastened to 
any kind of carriage, and abandoned to its fate, it is 

almost sure to be broken. 

To make and reduce an Observation of the Barometer. 
■First read off and write down the reading of the 



attached thermometer. Then give a few gentle taps on 



the instrument to free the mercm7 from adhesion to the 
glasB, avoiding to give it any violent oscillation. 



Adiust 



* For a permanently suspended or fixed barometer, the best tber- 
mometer ^ould be one -svith a tubular bulb of equal bore and thickness 
of glass with the barometer tube, and extending in length from the 
cistern to the exposed face of the instrumexit, and as close to the baro- 
metric column as is consistent with the structure of the upper \yorks. 
Immersion of the ball of the attached thermometer in the cistern is the 
worst arrangement of any. 



276 



METEOROLOGY. 



J 



I , 




[Sect. IX, 



the lower level to the fiducial point, if such be the con- 
truction of the instrument. Then set the index to the 
upper surface of the mercurial column^ placing the eye so 
as to bring its back and front lower edges to coincidence, 
and to form a tangent to the convexity of the quicksilver. 
If the insti'ument have no tubular or double-edged index, 
the eye must be carefully placed at the level of the upper 
surface to destroy parallax. Whatever mode of reading 
is adopted should be always adhered to. A magnifier 



should be used to make the contact and to read the ver- 
nier, and the reading immediately written down and 
careful] V entered on the register. 



r 

As soon after the observations have been made as cir- 
cumstances will permitj the reading of the barometer 
should be corrected for the relation existing between the 
capacities of the tube and cistern (if its constructiou be 
such as to require that correction), and for the capillary 
action of the tube ; and then reduced to the standard 
temperature of 32^ Fahr., and to the sea-level, if on ship- 
board. For the first correction the jieutral point should 
be marked upon each instrument. It is that particular 
height which, in its construction, has been actually 2uca- 
sured from the surface of the mercury in the cistern, and 

the scale. In general the mercury will 
stand either above or below the neutral point ; if ahove^ a 
portion of the mercury must have left the cistern, and 
consequently must have lowered the surface in the cistern : 
in this case the altitude as measured by*the scale vs^ill be 

if below. The relation of the 
capacities of the tube and cistern should be experi- 
mentally ascertained, and marked upon the instrument 





too short — vice 



versa 



h^ 



I 



V 



( 



t 






s. 



y 



'/ 



Sect. IX.] 



METEOROLOGY 




"7 



( 




the Tuaker. Suppose tlie capacity to be tV, marked 
thus on the instrument, " Capacity rV :" this indicates 
that for every inch of variation of the mercury in the 
tube, that m the cistern will vary contrariwise A th of an 

When the mercury in the tube is ahove the neutral 
point, the difference between it and the neutral point is 
to be reduced in the proportion expressed 



incl 




the 



/ 

I 



the quotient added to the observed height ; if helow, sub- 
tracted from it. In barometers furnished with a fiducial 
point for adjusting the lower level, this correction is 



superfluous, and must not be applied. 

The second correction required is for the capillary 
action of the tube, the effect of which is always to depress 
the mercury in the tube by a certain quantity inversely 



proportioned to the diameter of the tube. Tliis quantity 
should be experimentally determined during the con- 
struction of the instrument, and its amount marked upon 
it by the maker, and is always to be odded to the height 
of the mercurial column, previously corrected as before. 
For the convenience of those who may have barometers, 
the capillary action of which has not been determined, a 
table of corrections for tubes of different diametors is 
placed in the Appendix, Table I. 

The next correction, and in some respects the most 
important of all, is that due to the temperatur- of the 

mercury in the barometer tube at the time of observa- 
tion, and to the expansion of the scale. Table II. of 
the Appendix gives for every degree of the thermometer 
and every half-inch of the barometer, the proper quantity 
to be added or subtracted for the reduction of the ob- 



t ■ 
IP 




^-a=- 



-^'r. 



9 



78 



METEOROLOGY. 



[Sect. IX. 



i ■ 



I 



i 

f 

i 



< 

4 



i 



* 

Tl 
^ 




sensed height to the standard temperature of the mercury 
at 32^ Fahr. 

After these the index correction should be applied. 
This is the amount of difference between the particular 
instrument and the readings of the Royal Society's flint- 
glass barometer when properly corrected, and is generally 
known as the zero. It is impossible to pay too much 
attention to the determination of this point. For this 
purpose, w^hen practicable, the instrument should *be im- 
mediately compared with the Royal Society's standard, 
and the difference of the readings of both instruments, 
when corrected as above, carefully noted and preseryed. 
Where, however, this is impracticable, the comparison 
should be effected by means either of some other standard 
previously so compared, or of an intermediate portable 
barometer, the zero-point of which has been well deter- 
mined. Suspend the portable barometer a.s near as con- 
venient to the ship's barometer, and after at least an 






hour's quiet exposure, take as many readings of both 
instrumxTxts as may be necessary to reduce the probable 
error of the mean of the differences below O'OOl inch. 
Under these circumstances the mean difference of all the 
readings will be the relative zero or index error, whence, 
if that of the intermediate barometer be known, that of 
the other may be found. As such comparisons will 
always be made when the vessel is in port, sufficient time 
can be allowed for making the requisite number of ob- 
servations : hourly readings would perhaps be best, and 



they would have the advantage of forming part of the 
system when in operation, and might be accordingly used 
as such. 



) 



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Sect. IX.] 



METEOROLOGY 



07Q 



It is not only desirable that the zero point of the baro- 
raeter should be well determined in the first instance ; 
it should also be carefully verified on every opportunity 
.hich presents itself And in the first instance, previous to 



Uie 



sailing, after suspending the barometer on shipboard 
should be re-compared with the standard on shore by 
intervention of a portable barometer, and no opportunity 
should be lost of comparing it on the voyage by means of 
such an intermediate instrument with the standard baro- 
meters at St. Helena, the Cape of Good Hope, Bombay, 
Madras, Paramatta, Van Diemen's Island, and with any 
other instruments likely to be referred to as standards, or 



A.ny vessel having a 



e 



comparative readings 



employed in research elsewhere. 

portable barometer on board, the zero of which has bcai 
well determined, would do well on touching at any of 
the ports above-named to tak 
with the standards at those ports, and record the differ- 
ences between the standard, the portable, and the ship- 
barometers. By such means the zero of one standard 
may be transported over the whole world, and those of 
others compared with it ascertained. To do so, however, 
with perfect effect, will require that the utmost care 
should be taken of the portable barometer ; it should be 
guarded as much as possible from all accident, and should 
be kept safely in the "portable" state when not im- 
mediately used for comparison. To transport a well- 
authenticated zero from place to place is by no means 

Neither should it be 



a point of trifling importance. 



executed hurriedly nor negligently. Some of the greatest 
questions in meteorology depend on its due execution, 
and the objects for which these instructions have been 



i 
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280 



METEOROLOGY. 



[Sect. IX. 



prepared will be greatly advanced by the zero points of 



ail barometers being referred to one common standard - 



Upon the arrival of the vessel in England, at the ter- 
mination of the voyage, the ship's barometer should he 
again compared with the same standard with which it 

T ■ 

was compared previous to sailing ; and should any differ- 
ence be found, it should be most carefully recorded. 

Tlie correction for the height of the cistern above or 
beloiv the water-line is additive in the former case 
subtractive in the latter* Its amount may be taken 



nearly enough, by allowing 0*001 in, of the barometer 



for each foot of difference of level. 

An example of the application of these several cor- 
rections is subjoined : — 



Attached Therm. 54'^' 3. 



Data for the correction of the 

Instrument, 



Barometer reading 
Corr. for capacity 



29*409 
•Oi. 



>* I 



Corr. for capillarity . 



Corr. for temperature 



Corr. for zero and water- 
line .... 4- 



29*392 
»032 

29-424 

•068 

29-356 



Neutral point i . . . 
Capacity ^ 

Capillary action . . + 

Zero to Rotal Society , 4- 

Corr. for altitude above 

water-line . ^ • + 



30»123 



•032 
•03G 



004 



040 



A J'^rcgate 
sea-level 



pressure at 

• . • . 29*396 



Thermometers.— 'Th^ observer should be furnished with 



a delicate and accurate thermometer, most carefiillv com- 
pared with a perfectly authentic standard, at several tem- 

considerably, and of which the freezing 



tures 




point has been most scrupulously verified. This he should 



keep 



s 







a tht;rmometer of reference, and every 



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con 
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any 
rair 

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Ca, 



>e 



qu:„ 



,1 



-01 

aijn 








>v. 



i f* 



Sect. IX. 1 



METEOROLOGY. 



281 



tliermometer he employs should be eonipafed with it, so 
us not to leave a doubt as to the amount of their constant 
diffi^rence exceedino- a tenth of a degree. To n::ke such 
comparisons, long rest, in contact, in a box staffed with 
cotton, allowing only tbp portions of the scales where 
read off to be from time to time uncovered for that 
purpose, is the best mode of insuring their perfect identity 
of temperature. If, in any instance, the zeros differ in 
different parts of the scales, a table of reduction to the 
standard will require to be constructed. The com 
parisons should be repeated at not very distant interval 
of time, especially in the case of self-registering " 
mometers, whose index-error is constantly changing, and 
requires great watchfulness. In registering thermo- 



C3 



ther- 



meters record but do not appl^ their zeros. 
Ill placing the M 



Thermometer, an exposure 

should\e chosen perfectly shaded both from direct sun- 
shine, and that reflected from the sea, or radiated from 
any hot object. It should be especially guarded from 
rain and from spray, so that the bulb should never be 
wetted, also from warm currents of air and from local 
radiation; completely detached from contact with the 
ship's side, and fully exposed to the external air. In 
readins? it the observer should avoid touching, breathing 



V 



on, or in any way warming it by the near approach of his 
person ; and in night-observations particular care should 
be taken not to heat it by approach of the lignt. 
quicker tlie reading is done the better. 



The 



At nieiit it 



fm 



should be completely screened from the sky, so as to 
annihilate all loss of heat by upward radiation ; a light 
frame-case uf double wire-gauze will perhaps be found 




\ . .-h 



I 



f 

} 



I 



i 



i -- 



282 



METEOROLOGY. 



[Sect. IX 



a secure and efEcient protection both from injury and 



xious 



The Self-registering Thermometers should he placed 
with the same precautions as the external thermometer 
and in similar exposures, and so fastened as to allow one 
end to be detached and lifted ; so that the indices within 
the tubes may slide down to the ends of the fluid columns 
which they will readily do on gentle tapping. They are 



apt to get out of order by the indices becoming entangled, 



or by the brcctkiug of the column of fluid. When 
happens to the spirit-thermometer, it is easily rectified 
by jerking the index down to the junction of the bulb 
and tube: then, by cautiously heatiug and cooling 



alternately the bulb, tube, and air-vessel at the top, the 
disunited parts of the spirit m,ay be distilled from place 
to place till the whole is collected into one column in 
union with that in the bulb. 

When the steel index of the mercurial thermometer 
becomes immersed in the mercury, first cool the bulb (by 
evaporation of ether, if necessary) till the mercury is 
either fairly drawn below the index, or the column 

leaving the index with mercury above it. 



. m 




Loosen the index by tapping, by a magnet, or by heating 
the tube, then apply heat to the bulb, and drive the 
index with its siiperincumbGnt mercury up into the air- 
vessel When there, hold the instrument bulb down- 
wards, and, suspending the index by a magnet, effect a 
union between the globule of mercury and the column 
below, by continuing to apply the heat till the latter 
rises into the air-vessel, As the bulb cools the whole 
merciu-y should descend in an unbroken column, after 



t 



f 



b 



,. ^ \t 



^•' 





atient 



I c 



;i 



P 

used- 

M h S_i *■ 

1. ^ 



^-v^ 



•^\ 



fcesr 

oc:-. 1 
and ?c 



CUffi 



iio 



.( 



tberm 



i 



rvt^'^y 



f- 



I H 






^ ^ 



Tb.ati 



II 



uard. 

The 



^*'Ul 



Hil 



.* :^ 









\ - ' 



» 



ft 







I 

h 

h 

I 



Sect. IX.] 



METEOROLOGY, 



•* 



83 



Much 



which the index may he restored to its place, 
patience and many trials are often required for success. 
An oil-lamp with a very small clear 



flam 



should De 



used 



Both the self-registering thermometers should be 



9 h. A.M. observation, as it is 



very improbable that the temperature at that hour should 
be such as to obliterate either record of the preceding 






^-- 



24 hours. 



Double maxima and minima, when 



thev 



S' 



occur, if remarkable, should be recorded as supernumerary 
and sepnrately in a diai-y, and their accompanying cir- 
cumstances noted. 

The observer should he furnished with several other 

thermometers, all of sufficient delicacy to allow of es- 



timating tenth 



s 



of degrees, for observation of the 



temperature of the sea, or of the earth, ( 



on 



,^ 




rain, &c., and for a reserve in case of 
accident. All should he compared with the standard. 
That in habitual use for the sea temperature should be 
defended from accident in the act of immersion by a wire 



/ 



guard. 



The tliermometcr for solar radiation should have its 
bulb blackened with a coat of Indian ink. It should be 
defended from currents of air by enclosure in a. glass tube : 
and it would add infinitely to the value of a series of 
observations made with it if this tube were exhausted and 
hermetically sealed. Its exposure to the sun should be 
perfectly free and full, and it should he suspended in 
free air, quite out of reach of any support or object 
heated by the sun's rays. 



J. 



Hyu 



are of very yarious constinictionSj and 



\\ 



I 



284 



Meteorology. 



[Sect. IX. 



depend 



jena on -v 



_ X 

ery different principles. That which we 
recommend in preference to, and as having almost univer- 
sally superseded in practice every other,* consists of two 
thermometers, the bulb of the one being dry and of the 
other wet ; being kept so by a covering of muslin, con- 
nected by a wet roll of cotton (lamp wick) with a small 
Clip of distilled or rain-water placed close beneath it, so 
as to absorb and communicate water by capillary attrac- 
tion. In frosts this arrann;eruent Is unavailing^, and water 



must be poured on the muslin envelope, and allowed to 
freeze into a coat of ice, from which evaporation will still 
go on and depress the temperature, as if still liquid. They 
should be placed and observed in such locality as shall 



afford the best chance for procuring a fair indication of 



the moisture of the general atmosphere, and by no means 
in any confined or ill-ventilated situation between decks, 
where many persons habitually congregate, or which, from 
any other cause, is usually or periodically damp The 
whole instrument should be protected with a cap of wire- 
work to defend it from injury : this, if it interfere with 

hould be removed a quarter of an hour 
before the observation. In reading the thermometers begin 
with the dry one, and use all the precautions recommended 
with respect to the ^^ external '' thermometer. Enter the 
simple readings, but at the head of each column place the 
zero correction (with its proper sign) required for its ther- 
raom^eter fa general rule for all thermometric entries), and 



the readings, s 



\ 



■ The hair hygrometer is delicate, exceedingly liable to derangement, 
and, except prepared with extraordinary care, uncertain. DanielFs dew- 
point hygrometer, excellent in theory, is very costly on account of its 
great consumption of ether, and scarcely useable in hot climates, owing 
to the difficulty of preserving that liquid. 



I 



k 




•I 




Serf 



. 1^1 



Icav^ 



a 



IB 



c 



;al^ ^ 






,1 



iui ' ■ 



F==/' 




is abo^-e 

?ro; 



t 

n 



C 



r .i.: 



\^^^ 



lb K 



:Ci^ 






aD( 



IF ' 

1 1 v*J 



(4 the 



V t 



ii\J 



Cfiyv 



^p f <^ ' 



tlie 



m», 



con 



^6'-' 



ver, 



T" f 

■ "ion 

h the ?;. 



asoiT^^* 






e 






is ^- 



L 

tlier ... 



1^ 






H i 



in a 



-< .. 



r 

► 






, F 



Sect. IX.] 



METEOROLOGY 



r\ <-^ f^ 

2^0 



leave a blank column for the " hygroraetric depression," 



must be 



in calculating which subsequently the zeros 
applied. The reduction of the observations to derive the 
elastic force of vapour at the dew-point is effected by the 
formulae of Dr. Apjohn : 



F=/ 



d 



h 



88 ' 30 



. . (a); F=/ 



d 



h 



96 30 



• • f 



(h) 



(a) 



(^>) 




In these d is the hy- 
)f the barometer, / the 



elastic force of vapour for the temperature shown by the 
wet thermometer, to be taken from Table III, Appendix 
and F the elastic force of vapour at the dew-point 



hich 



( 



other quantities being 



) 



formuls8 



enable us to calculate. With F so calculated enter the 
same table under the column of Force of Vapour, and 
the corresponding temperature is the dew-point, which, 
however, is not wanted to be known but as a matter of 

curiosity. 

The Rain-Gauqe.—Thh may be of very simple con- 
struction. A cubical box of tin or zinc, exactly ten inches 
by the side, open above, receives at an inch below its edge 
a square funnel, sloping to a sm,all central liole. On one of 
the lateral edges of the box, close to the top of the cavity, 
is soldered a short pipe, in which a cork is looseli/ fitted : 
the whole should be well painted. The water which enters 
the reservoir through the funnel hole is poured through 
the short tube into a cylindrical glass vessel, graduated 
to cubic inches and fifths of cubic inches. Hence, one 
inch in depth of rain in the gauge will be measured by 



B^ 



^ J-r 



T: 



p- 



V 



.^ 



f 




% 



^T^^-^ 



s 



I 



28< 



> 



METEOROLOGY. 



[Sect IX. 



100 inches of the graduated vessel, and a thousandth 
of an inch may easily be read off. It is very difficult to 
place the rain-gauge properly on shipboard, and its 
entries therefore require constant explanatory notes, 
pointing out causes tending to disturb its influence. In 



fact, exceptin 




( 



it seems hardly possible to devise a tolerably permanent 



situation for it, O 



the 



a perfectly open exposure 



on 



chosen. 



ground, or veri/ little elevated above it, should be 
■ The quantity of water should be daily mea- 
sured and registered at 9 a.m., unless the fall of rain be 
so heavy as to endanger filling the instrument witlun the 
24 hours, when this operation should be performed as 
often as needed. Snow collected or water frozen in the 
reservoir should be melted. 

The Anemometer. — Lind's would appear to b-- the only 
anemometer which can conveniently be used on shipboard. 
It is adjusted by filling it with water till the liquid in both 
legs of the syphon corresponds with zero of the scale. It 



is to be held perpendicularly with the mouth of the kneed 
tube turned towards the wind, and the amount of depres- 
sion in the one leg and of elevation in the other are to be 
noted. The sum of the two is the height of the column of 
water which the pressure of the wind is able to support : 
and the force of the wind on a square foot is obtained 
from this L.ight by Table IV. of the Appendix. In great 
degi*ees of cold a saturated brine may be used which does 
not freeze, and whose specific gravity being 1 '244, the 
force given by the table must be multiplied by this 
factor. In addition to the regular hours of observation 
this instrument should be observed in storms, white 



i 



S<=^ * 



^1 



4b, 



of ^' ' 



e 



T 

slieet ■•■ 



>■" 



^ 



Ui 



. 1 A 



'^10* 



dii'ectic] 



-L _ ^ -"^ 



ifr-£^ *■ 



.) 



it I 



t., ;i.ii.lU 



Ivtli 




} 

The. 

oated : 



of tk> 



* I 



cemenl.. 



1 ''^^ 






JX 



-^ 



of 



1 



Jx . 



* - 




-• ar. : 



wrench 
The J 

a spirit ; 



ver^ 1 



(>ij 






tur^ 



the- , 



^it 



^^feT>4 : 



1 



.'J 







1 







I 



»• » 



•ft> 



» 



Sect. IX.] 



METEOROLOGY. 



2 



o t 



squalls, or other circumstances of interest ; the direction 
of the wind as well as its force should be registered at 
each observation; and for tliis it is well to hav- asmal) 
compass with a vane of card, or thin and very moveable 
sheet brass, which may be fastened on the top of the 
anemometer, and which will indicate the direction in 
which its opening should be turned. In concluding the 
direction and the force of the wind from the vane and 
anemometer readings, a correction depending on the 
direction and velocity of tbe ship's motion is required in 
strictness. But such corrections are not usuaUi/ applied, 
and it may be doubted whether the observations can be 
acciu-ately enough made to render it worth while to 

apply them. 

The Actinometer consists of a large hollow cylinder of 
glass, soldered at one end to a thermometer-tube, termi- 
nated at the upper end by a ball drawn out to a point, and 
broken off, so as to leave the end open. The other end 
of the cylinder is closed by a silver or silver-plated cap, 
cemented on it, and furnished with a screw, also of silver, 
passing through a collar of waxed leather, which is pressed 
into forcible contact with its thread, by a tightenin 
of large diameter enclosing it, and working into the silver 
cap, and driven home by the aid of a strong steel key or 
wrench, which accompanies the instrument. 

The axis of this screw is pierced to allow the stem of 
a spirit thermometer to pass out through it, the bulb (a 

very long one) 

perature of the enclosed liquid. 




screw 



The graduation is in 




the stem of the screw, which is prolonged to receive ana 



defend it. 



w 



- -c 



w^ 






r" 




.Ifi> 




288 



METEOROLOGY. 



Sect. IX. 



Sect 



---r-. 



•^ 






i 




lass, removable at pleasure. 



The cylinder is filled with a deep blue liquid (am- 
monio-sulphate of copper), and the ball at the top being 
purposely let!:, full of air, and the point closed with 
melted wax, it becomes, in any given position of the 
screw, a thermometer of great delicacy, capable of beino* 
read off on a divided scale attached. The cylinder is 
enclosed in a chamber blackened on three sides, and on 
the fourth, or face, defended from currents of air by a 
thick 

The action of the screw is to diminish or increase at 
pleasure the capacity of the hollow of the cylinder, and 
thus to drive, if necessary, a portion of the liquid up into 

the ball, which acts as a reservoir, or^ if necessary, to 
draw 

just fill it, leaving no bubble of air in the cylinder. The 
interior thermometer indicates the temperature of the 
blue liquid approximately for the subsequent reduction 
of the observation. 

To use the instrument^ examine first whether there be 
any air in the cylinder, which is easily seen by holding it 
levelj and tilting it, when the air, if any, will be seen to 
run alon 



back from the reservoir such a quantity as shall 




it 



If there be any, hold it upright in the left 
hand, and the air will ascend to the root of the ther- 



mometer-tube. 



.'The 



n, by alternate screwing 



and un- 



screwing the screw with the right hand, SiS the case may 



require, it will always be practicable to drive the air out 
of the cylinder into the ball, and suck down the liquid, 
if any, from the ball, to supply its place, till the air is 
entirely evacuated from the cylinder, and the latter, as 
well as the whole stem of the thermometer-tube, is full 
of the liquid in an unbroken column. Then, holding it 



the 



s 



T] 



IS » 



t 



clear 
force 

scre^ 
pour 
with 
clear 
repls 

T 

obse: 
shar] 
or n 
the i 



sure, 



sun 



) 



or ti 
part 

plac 
shoi 

stati 
wine 

sun 
as in 

door 
Penu 

sbou 

at hi 




Sect, IX.] 



METEOROLOGY. 



289 



» 



Vi 





i 





% 



* 



i 



I - 



if 



I 



I ' 





1- 



horizontally, face upwards, slowly and cautiously unscrew 
the screw till the liquid retreats to the zero of the scale. 

The upper bulb is drawn out into a fine tube, which 
is stopped with wax. When it is needed to empty, 
cleanse, and refill the instrument, liquid must be first 
forced up into the ball, so as to compress the air in it. 
On warming the end, the wax will be forced out, and the 
screw being then totally unscrewed, and the liquid 
poured out, the interior of the instrument may be w^ashed 
with water slightly acidulated, and the tube, ball, &c., 
cleansed, in the same way, after which the wax must be 
replaced, and the instrument refilled. 

To male an observation with the actinometer, the 
observer must station himself in the sunshine, or in some 
sharply terminated shadow, so that without inconvenience, 
or materially altering his situation, or the exposure of 
the instrument in other respects, he can hold it at plea- 
sure, either in full sun or total shadow. If placed in the 
sun, he must provide himself wath a screen of pasteboard 
or tin plate, large enough to shade the whole of the lower 
part or chamber of the in 



instrument, which should be 
placed not less than two feet from the instrument, and 
should be removable in an instant of time. The best 
station is a room with closed doors, before an open 



window, or under an opening in the roof into which the 
Sim shines freely. Draughts of air should be prevented 
as much as possible. If the observations be made out of 
doors, shelter from gusts of wind, and freedom from all 
penumbral shadows, as of ropes, rigging, branches, &c.^ 
should be sought. Generally, the more the observer is 
at his ease, with his watch and writing-table beside him, 



o 



4£- 



*J^_ 









OS^^^ 



r:^ 



290 



METEOROLOGY. 



[Sect IX. 



the better. lie should have a watch or chrononicter 



beatine: at least twice in a 






concl 



^t;i;uiiuj and provided with a 



second hand ; also a pencil and paper ruled, according 
to the form subjoined, for registering the observations. 
Let him then grasp the instrument in his left hand, or, if 
he have a proper stand (which is preferable on shore or 



m a 



buildin 





, othervvisc firmly support it, so as to 
expose its face perpendicularly to the direct rays of the 



sun, as exactly as may be. 



The liquid, as soon as exposed, will mount rapidly in 
the stem. It should be allowed to do so for a minute 
before the observation begins, taking care, however, not 
to let it mount into the bulb, by a proper use of the 
screw. At the same time the tube should be carefully 
cleared (by the same action) of all small broken portions 
of liquid remaining in it, which should ail be drawn down 
into the bulb. When all is ready for observation, draw 
the liquid down to zero of its scale, gently and steadily ; 
place it on its stand, with its screen before it, and proceed 
as follows, first reading off the internal thermometer. 



Having previously ascertained how many times (sup- 
pose 20) the watch beats in five seconds, let the screen 






withdrawn at ten seconds before a complete minute 
shown by the watch, suppose at 2^ 14™ 50*. From 50' 
to 55^ say 0, 0, 0, . . . . at each beat of the watch, 
looking meanwhile that all is right. At 55' complete, 



count 



0, 1, 2, . . , . up 



to 



20 beats, or to the whole 






\ 



I 



h. 
2 



4 






^. 



* This may consist of two deal boards, eighteen inches long, conBCcted 
by a hinge, and kept at any required angle by an iron, pointed nt each 

The upper should have a little rabate or moulding fitting loosely 
round the aetiaometer, to prevent its slipping off. 



end. 






i 



^ 



Sect, IX.] 



METEOROLOay. 



291 




r 



minute, 2^ IS'"" 0% keeping the eye not on the watch, but 
on the end of the rising column of liquid. At the 20th 
beat read off, and register the reading (12'' -0), as in 



wait, watching 



column 3 A, of the annexed form. Then 
the column of air above the liquid, to see that no blebs 
of liquid are in it, or at the opening of the upper bulb 
Twhich will cause the movement of the ascendinsr column 



tarts) 



the 



mill 



ate is nearly 



elapsed. At the 50th second begin to watch the liquid 
rising ; at 55* begin to count 0, 1, 2, up to 20 beats, as 
before, attentively watching the rise of the liquid ; and 
at the 20th beat, or complete minute (2^^ IQ^ 0% read 






]m^ 




1. 

Date and times of 
Observation. 

, 1850, 

Oct. 30. 



Initial. 



h. 

9 



m. 
15 

16 

18 

19 

21 

22 

24 



s. 


30 


30 



30 




Terminal 



m. 

16 
17 
19 
20 
22 
23 
25 



s. 


30 


30 







2. 







eg u 




X 
© 
X 

© 

X 

© 



3 



Readings of the 
Instrument. 



A. ! B. 

Initial. ' Terminal 



+ 12'0 

45*2 

14-8 

28'0 

9-4 



t 



46-6 
9-01 



+43-3 
42-8 

48-2 
26'8 
43-9 
45-5 
43-2 



4. 



5, 



Ciiange - , 

pg^ Internal 

minute. '^^^^«^^' 



B-A. 



+ 31-3 

- 2*4 

+ 33* 

— 1- 



4-33 
- 1 



4 
4 

5 

E 

i! 



34*2 



75-5 



t. 



Remarks. 



The times r. re- 
duced to appa- 
rent timej or tc 
the 3un*s hour 
angle from the 
meridian. 

Zero witiitlTawn, 

Blackened 

Tlierm. 106 '3. 



n i^ 



. 1 



) 




off, and instantly shade the instrument, or withdraw it 
just, out of the sun and penumbra. Then register the 



reading off (43' -3) in column 3, B, and prepare for 
the shade observation. All this may be done without 
hurry in 20 seconds, with time also to withdraw the 
screw if the end of the column be inconveniently high in 

o 2* 



202 



METEOROLOGY. 



[Sect. IX. 



the scale, which is often required. At the 20th second 
prepare to observe; at the 25th begin to count beats, 
0, 1, 2, .... 20; and at the 20th beat, ^. e. at 2^^ 16^ 
SO^ read off, and enter the reading in column 3, A, as 
the initial shade reading (45'''2). Then wait, as before, 
till nearly a minute has elapsed, and at 2^ 17^ 20^again 

At 17^^ 25' begin to count beats; at 17^^ 30' 




read off, and enter this terminal shade reading (42 '8) hi 
column 3, B, and, if needed, withdraw the zero. 

A.gair wait 20% in which interval there is time for the 




entry, &c. At 17"^ 50^ remove the screen, or expose the 
instrument in the sun ; at 55^ begin to count beats ; and 
at the complete minute, 18"^ 0% read off (M'^'S), and so 
on for several alternations, tailing care to begin and end 
each series with a sun ohsei'vation^ and to read off the 
internal thermometer at the end of each set, or, if the 
observations be continuous, at every fifth sun observation. 
If the instrument be held in the hand, care should be 
taken not to change the inclination of its axis to the 
horizon between the readings, or the compressibility of 
the liquid by its ovfn weight will produce a very per- 
ceptible amount of error. 

In the annexed form column 1 contains the times, 
initial and terminal, of each sun and shade observation. 
Column 2 expresses by an appropriate mark, and x ? 
the exposure, whether in sun or shade. Column 3 
contains the readings, initial and terminal (A and B). 



Column 4 gives the values of B — A, with its alge- 
braical sign expressing the rise and fall per minute. 

tfulness 



for£re 



And here it may be observed; that if by 

the exact minute be passed, the reading off may be made 



] 



s 



\ 



1 



. "* . ^^ 



ri-. 



■ 








1^ 



J 



* 



■ ' 



t\ 



<<C^ 



tOCl^ 



t. IX.] 



METEOROLOGY. 



9 Q ^, 



at tlie next 10% and in that case the entry in coliinin 4 
must be not the whole amount of B - A, but only ftiis 
of that amount, so as to reduce it to an interval of 60^ 
precise. Column 5 contains readings of the internal 
thermometer ; column 6 is left blank for the 

column 7 are entered re- 



^•'sult'" 



Ca 



o 



when reduced ; and in 

marks, such as the state of the sky, wind, &c. ; as also 

(when taken) the sun's altitude, barometer, thermometer, 

and other readings, &c. 

A complete actinometer observation cannot consist of 
less than three sun and two shade observations inter- 
mediate ; but five sun and four shade are m.uch better. 
In a very clear sunny day it is highly desirable to 
continue the alternate observations for a long time, even 
from sunrise to sunset, so as to deduce by a graphical 
projection the law of dhirnal increase and diniinution 
of the solar radiation, which will thus readily become 
apparent, provided the perfect clearness of the sky con- 
tinue,— an indispensable condition in these observations, 
the slightest cloud or haze over the sun being at once 



marked 




a 



diminution of resulting radiation 



To 



detect such haze or cirrus, a brown glass applied before 
the eye is useful, and by the help of such a glass it may 
here be noticed that solar halos are very frequently to be 
seen when the glare of light is such as to allow no- 



+ 



thing of the sort to be perceived by the unguarded eye. 
When a series is long continued in a good sun, the 



instrument grows very hot, and the rise of the liquid in 



the sun observation decreases, while the fall in the shade 
increases ; nay, tow.irds sunset it will fall even in the sun. 



( 




t> 



294 



METEOROLOGY. 



[Sect. IX. 



I 



! 



j 



I 

i 



; O 



impeach the fidelity of the 



t) 



perfectly in order, and produces absolutely no irrera^ 
larity in the resulting march of the radiation. Only it i 



necessary in the reduction of such observations to attend 

illy to the algebraic signs of the differences in 
column 4. 

Every series of actinometer observations should be 
accompanied with notices in the column of remarks of the 
state of the v^^ind and sky generally, the approach of any 

the 



es- 



cioud (as seen in the coloured glass) near to the sun ; 
barometer and thermometers, dnj and tcet, should 
pecially be read off more than once during the series, if 
a long one, and, if kept up during several hours, hourly. 
The blackened thermometer for solar radiation should 
also be read off at the middle of every set, so as to accu- 
mulate a mass of comparative observations of the two 
insti'uments. The times should be correct to the nearest 

minute at least, as serving to calculate the sun's altitude ; 
but if this b 



a 



•) 



pocket sextant, or even by a style and shadow, frequently 
(at intervals of an hoiu' or less) when the sun is rising or 
setting, it will add much to the immediate interest of the 



observations 



When the sun is near the horizon, its 
reflection from the sea, or any neighbom-ing water, mus 



t 



be prevented from striking on the instrument : and 



1 



great 



m aJpme countries. 



Every actinom.eter should b 



provided v/lth a spare 
glass, and all the glasses should be marked with a dia- 
mond ; and it should always be noted at the head of the 
column of remarks whir.h ctIass is ns^d. ns the co- 



eniarks which glass is used, "=' 



*1 W 



( 









«. 



# 



f 




tf 



i'^r 



***** 



4 



P 




Sect. IX.] 



METEOHOLOGY 



c> 



95 



( 



of radiation var 



IPC witli 

A'^-fw' T^ i. VAX 



the glass used. 



To reduce provmonally a set of 



rfVt 



ohserva 



#^ 



tions 



If the set consist of orly four or five sun obser- 
vations, with intermediate shades, take the mean of the 
" changes per minute " in column 4, for all the sun and 
for all the shade observations separately, attending duly 
to the signs. Change the sign of the latter mean, and 
add it to the former. The aggregate will be the un- 
corrected radiation in parts of the scale. To correct it 
for the unequal dilatability of the liquid, take the mean 
of the temperatures shown by the internal thermometer at 
the beginning and end of the set, and with it enter the 

Table V., which contains the factor by 



^^ppendix 



which the uncorrected radius is to be multiplied. 



If the 



series 



consist of more than a quadruple or sextuple 
observation, it must be broken into quadruplets, or quin- 
tuplets, and each reduced separately as above. 

The abstract unit of solar radiation to be adopted in 
the ultimate reduction of the actinoractric observations 
is the actine, by which is understood that intensity of solar 
radiation which at a vertical incidence, and supposing it 
wholly absorbed, would suffice to melt one millioTitli part 
of a metre in thickness from the surface of a sheet of 
ice horizontally exposed to its action per minute of mean 
solar time ; but it will be well to reserve the reduction of 
the radiations as expressed in parts of the scale to their 
values in terms of their unit until some future and final 
discussion of the observations. 

Meanwhile no opportunities should be lost of comparing 



fe. 



i 



I 
I 



-J 






296 



METEOROLCGl 



i © 



[Sect, IX. 



tO£?ether the iridications of different actinometers imder 



similar 



and favonrable circumstancesy so as to establish 
a correspondence of scales, which in case of accident 



happening to one of the instruments will preserve its 



registered observations from loss. The comparison of 
two actinometers may be executed by one observer using 
alternately each of the two instruments, beginning and 
ending with the same ; though it would be more con« 
veniently done by two observers observing simultaneously 
at the same place, and each registering his own instru- 
ment. An hour or two thus devoted to comparisons in a 
calm clear day, and under easy circumstances, will in all 
cases be extremely wdi bestowed. In frosty or very cold 
weather the instrument should be exposed, for some time 
previous to commencing tlie observations, to the sun, 
which, by warming the liquid, increases its dilatability, 
which at low temperatures is inconveniently small. 

Neither should each observer neglect to determine for 
himself the heat stopped by each of his glasses. This 
i^ay be done also by alternating quadruplet observations 
made with the glass on and oiF, beginning and endin 

and (as in all cases) beginning and 
ending each quadruplet with a sun observation. For the 
purpose now in question a very ealm day must be chosen, 
and a ereat many quadruplets must be taken in suc- 




with the glass oiF, 




cession 



The actinometer is w^cll calculated for measuring the 
defalcation of heat during any considerable eclipse of 
the sun. The observations should commence an hour 
at least before the eclipse begins, and be continued an 



hour 



beyond its termination, and the series should be 



( 

1 



. 




4 



T 







f 



t 



^ 



**• 



.^ 



Sect. IX.] 



METEOROLOGY. 



'297 



^. 



iramterrupted, leaving to others to watch the phases of 
the eclipse. The atmospheric circumstances should be 
most carefully noted during the whole series. 



Thermometers fi 



The measure 



of terrestrial radiation is of no less importance to the 
science of meteorology than that of solar radiation, but 
no perfect instrument has yet been contrived for its deter- 
mination. Valuable information, however, may be derived 
from the daily register of the minimum nocturnal tem- 
perature of a register spirit-thermometer, the bulb of 
which is placed in the focus of a concave m.etaUie mirror, 
turned towards the clear aspect of the sky, and screened 
from currents. Such a thermometer may be read oflF and 
registered at the regular hours by day as well as by night, 
but it must be screened from sunshine, and a thermometer 



same 



Reqist^rs. 



To keep a m-eteorological register with due regularity^ 
a skeleton form (No. 1) should be prepared, by ruling 
broad sheSts of paper into columns destined for the 
reception of the daily and hourly entries in tlieir uncor- 
rected state, as read off or otherwise noted. This form 



may 



be most 



advantasjeouslv arranged in groups of 



columns, with general heading {A^ B, C, &c.) 



ticular sub-headings (a, b, c, 







as to class the 



ft 

entries in an order favourable to subsequent comparison 
and reduction. Thus, the group A should carry the 

ire; C, Temperature oj 



Date : B. Press 



air; D, Moisture; E, Radiation.; F, Ternperatm 
ivater ; G, Wind; H, Cloud; /, Weather; 



e 



f 






Rain 



o 3 



- -fll'i^-^— 






iT+ 



1 

1 



I 



208 



METEOROLOGY. 



[Sect. IX. 



Z, Rej 



and opposite to every page ruled for 



blank i 



Under 



o 



o 



e; 



ia will 



indicate the day of the month (marking the Sundays with 
S, and the days of new, full, and quarters of the moon 
wdth their appropriate marks #, s, c^ c) ; and 



Ab will 
contain the hours of observation in each day, following 

the civil reckoning of time, 

B will contain two sub -headings, Ba^ Bb^ correspond- 
ing to columns in w^iich are entered respectively the 



readings of the barometer and its attached thermometer. 

C will contain three : viz, Ca for entries of the ex- 
ternal thermometer ; Cb^ the daily maxima ; and Cc, the 
daily minima, placed opposite to the hours at which they 
are read oft" on the self-registering thermometer. 

D will have two, Da and Db : viz. the readings of the 
dry and v^et bulbs of the hygrometer. 



Under E will stand three 



o 



ub-columns, Ea for solar, and 

the 



Eb^ Ecj for terrestrial radiation. Ea will contain 
readings of the black-bulb thermometer exposed in the 
exhausted tube to the sun at such of the regular hours 
when it can be observed ; Eh those of the thermometer 
exposed to clear sky in the metallic reflector; and Ec 
those of a similar tliermometer placed close beside it, and 
iu all other respects similarly exposed. In these columns 
may also be entered the observed maxima of these ele- 
ments, whether obtained by watching the instruments or 
by self-registering ones ; and these observations should 



be distinguished from the others by enclosing them in 
parentheses, or miderlinlng them, &c. 

Pwill contain the temperature of the surface -water. 





VHi* 



vt -^i. 



t 



Cd 



I 










• -♦.» 



tl 



L.. 




*^ 



I 




Sect. IX.] 



METEOROLOGY 



29 




Fa 



o 



Fb, that at two fathoms depth : the latter not bemg taken 
more than once a day, except when Fa indicates some 

sudden change. 

G will contain the direction of the wind, per vane ana 
compass, in its first column, Ga ; and its force, as read off 
on the anemometer, in Gb. If there be an upper and 
under current of wind, both their directions should be set 



lik 



H 



He 



the 



amount of cloud in the region from the zenith down to 
0^ of altitude, and lib for the amount below that alti- 



cighth parts 



of the whole 

( which 



tude, each estimated in 

respective areas of sky included in the two regions '^w 

are equal), according to the best of the observer's ji 

ment. He will contain the prevalent character of cl 

according to the nomenclature of Howard ; denotin 

C cirrus, by K cumulus,'^ by S stratus, and by N nimbus, 

by double letters their combination in transition from one 





) 



(tbus, K, 






the prevalence of one 



species of cloud in one and another in the other region. 
Two layers of cloud, one above the other, may be denoted 
by placing their characteristic letters above and below a 
line in the manner of a fraction. These forms of cloud 
are thus characterized :— Cirrus expresses a cloud re- 
sembling a lock of hair, or a feather, consisting of streaks, 
wisps, and fibres, vulgarly known as mares' tails. Cu- 
mulus denotes a cloud in dense convex heaps or rounded 

* To avoid the otherwise inevitablt; confusion of C and c in MS. 



^ ■* 



f ^ 



.^^ 



300 



METEOROLOGY. 



[Sect. IX, 



formsj definitely terminated above, indicating saturation in 
the upper clear region of the air^ and a rising supply of 
vapour from below. Stratus is an extended continuous 
level sheet, which must not be confounded with the flat 
base of the cumulus, where it simply reposes on the 
vapour plane. The cumulo-stratus, or anvii-shaped 
cloud, is said to forerun heavy gales of wind. Peculiar 
aspects of cloud, preceding gales, squalls, or hurricanes, 
should be specially described in the sheet of remarks, or 



in a jonrnal. Nimbu 



int<» a crown of cirrus above, and passing beneath into a 



;h< 



snower 



Under the heading I will stand a note of the general 



state of the weather, according to Admiral Beaufort' 



s 



system of abbreviations, which is as follows :— Numbers 
from 1 to 12 denote the force of the wind : thus, denotes 
calm ; 1, ligld air, just perceptible ; 2, light breeze, in 
which a ship, clean full, in smooth water, would go from 



one to two knot 



s : 




5 



aentl 






e oreeze 



f^ 



') : 4^ Tnoderate breeze (fi 



c 



royals, &c, ; o 



(from two to four 
tm four to six knots) ; 5, 
ould just carry on a wind 



n 



? 



c 




topgallant-sails) : 7, moderate gale (double-reefed, &c.) ; 
8, fresh gale (triple-reefed and courses) ; 9, stormy gale 



(close-reefed^ 



O 



etc.; ; 



10, 



( 



mam- 



1) I 11, storm (storm-staysails) 



12, hurricam (no canvas can etand). These numbers, in 
the absence of an anemometer, may be entered in column 



Gh. The follow] 
weatlier : 



Q 




a 



bbreviations denote the state of the 



I 



*' 



■* 




*. 






\ 



fc^ 



^. 



\ 







of 



Sect. IX.] 



METEOROLOGY. 



301 



b. Blue shj, be the atmosphere 

clear or heavy. 

c. Clouds. 







Sky 



Overcast. The whole 
vered with thick clouds. 



co- 



Detached passing p. Passing, temporary showers 



clouds. 



d. Drizzlivg rain. 

/- Foggy. 

g. Gloomy dark weather. 

A. Hail. 

I. Lightning. 

Misty hazy atmosphere 



m. -£ 



q. Squally. 

Bain. Contmued rain. 

s. Snoto. 

t. Thunder^ 

u. Ugly threatening appearance. 

V. Visibility of objects ; clear at 

mosphere. 
w. Wet. (Dew.) 



i 



E 



under any letter denotes a great degree. 

K contains only a column, Ka, for the quantity of 
rain, melted snow or hail collected in the rain-gauge at 
the regular liour. One entry a day will suffice, except 
in rains of unusual heaviness or in paroxysmal discharges, 

r 

which will require special note. There will always bo 
room in this column to note the temperature of the 
falling rain, if remarkable. 



Finally, i is a small column at tlie edge of the page, 



of refi 



from 1 to the 



number of Imes of entry in the page, to connect eacii 
entry with the remarks on it, or on any phenomenon which 
may have occurred in the interval since the last entry, 
which it will he probably necessary to enter on another 
sheet or interleaved page (carrying at its left-hand edge 
a similar reference column), or with any more extended 
notes whi(ih may form part of a diary such as every 
observant traveller or voyager ought to keep, and of 
which a summary for the month, so far as relates 
meteorological subjects, should be appended to each 
monthly register. 

Another skeleton form, No. II., should be prepared 



to 



302 



METEOEOLOGY. 



[Sect. IX. 



I 



i 

I 

1 



i 



I 



and ruled in corresponding columns, to receive the cor- 
rected and reduced results of the raw observation 



s in 



Form I. This should have the column ^^ as in Form 
I ; B will consist of a single column : viz. the barometer 
reduced to 32 ; C, of the same number as in Form I 
containing the corrected thermometer readings ; under D 
will come two columns. Da and Db^ of which the former 

Iry and wet 



will contain the corrected difference of th 



e ( 



bulb readings, and the latter the value of F^ the elasth 

force of vapour at the dew-point by the formula alread] 

given. E and F will merely contain the corrected valuei 



of the corresponding entries in Form I ; and if there be 



anything in the remaining columns requiring correction 



or reduction, it will here, of course, be done ; if not, 
those columns must be either carefully copied or simply 
referred to. In this form should be entered, when needed^ 
the monthly means of the several columns (in calculating 
w^hich care should be taken to verify the results by repe- 
tition) ; and it is recommended, before adding up the 
columns, to look down each to see that no obvious error 
of entry (as of an inch in the barometer, a very common 
error) may remain to vitiate the mean result. The pre- 
caution should also be taken of counting the entries in 
each column, so as to muke no mistake in the divisor. The 



^xxima 



iC 



and ranges of the instruments 



should also be entered. Except, however, the ship has 
been nearly stationary during the month, these calcula- 
tions and their results are of little utility. 

T^oth forms should be headed with the year and month 
on every page, and should bear the name of the ship and 




Li^erver^ 



f 



f 



1 



i 



1 



] 



i 



i 



i*. 



i 



^ 



»< 
\ 



»* 



^ 



I 



Sect. IX.] 



METEOnOLOGY 



303 



The observer will find it botli interesting and instructive 
in a high degree to project the reduced observations (as 
fast as reduced, or monthly) of the barometric pres- 



(the value of F 



iL^ 



mentioned), 



curves, by the aid of a paper of 
engraved' squares, divided into inches and tenths by 



and temperature, m 



vertical and horizontal lines. 



The comparison of the 



case 



tension is of especial interest, since there is great reason to 
believe that the diurnal fluctuation of the barometer is 
mainly, if not entirely, a hygrometric phenomenon arising 
from the superaddition of a variable hygrometric pressure 
to the otherwise uniform pressure of the dry atmosphere. 
The course of the barometric curve too will show far 
better than simple observation the chief maxima and 
minima which indicate the passage of the crests and 
troughs of atmospheric waves. And its continuance at a 
high or low level, or its gradual diange, corresponding 



over Ion 




progressive 



latitude and longitude, will enable the observer to trace 
out the limits of those deviations from the simple law of 
statical equilibrium which the researches of Schouw, 



Humboldt, and others have proved to exist more or less 
over the whole globe, and which those of Ermann in the 
Arctic, and King and Ross in the Antarctic regions have 



local 



to the 



enormous amount of a whole inch in the mercurial column. 

* Such papers may be obtnined from Messrs. W, H. Allen and Co., 
Booksellers to the Honourable East India Company, No. 7, Leadenhali- 
street, London. 












J ^* 



■m -^ 



304 



METEOROLOGY. 



[Sect. IX. 






Occasional Observations. 

There is much and most valuable matter for meteoro- 
logical observation and remark which cannot find a place 
in the regular entries of a register^ either from its occa- 
sional nature^ or from its statement requiring more 
detail than is consistent with the brevity of such entries. 
Observations of the Actinometer are of this kind, and 
require a separate register. Such also are all meteoro- 



logical phenomena of a transitory nature, as hurricanes 



thunderstorms, waterspouts, auroras, &c., of all which 
special and connected statements should be drawn up 
(embodying all notes made at the time) as soon after 



i 

1 



their occurrence as possible, and entered in a diary, care- 
lly noting all circumstances connecting them with the 
state of the atmosphere preceding and subsequent, and 
especially every precursory appearance or fact which 
may have left on the observer's mind the impression of a 

, Such also are those occasions of which the 




attentive observer will not fail to take advantage, when 
particular meteorological sequences of cause and effect 
stand out in unusual prominence, or when opportunity is 



offered for the exact or ai 




.s 



determination of 
ome datum of scientific interest. The following hints 
respecting observations coming under these descriptions 
will be worth attendina: to. 



Squalls^ Storms, 



Hur 



hardl 



icanes or Cyclones. — It is 
y necessary to impress on the nautical observer the 
xtreme importance of a minute attention io every adjunct 
of these formidable phenomena. From their first indi- 
cations they should be attentivelv watched in all their 






] 
i 



w 
^ 



i 

< 



1 



I 



» 



f 



\ 



\ 



\ 




V 



i 
I 






^ 



p>- 



Jb 



Sect. IX.] 



METEOROLOGY. 



305 



phases, with a vigilance proportioned to their actual or 
expected intensity. Nothing in the way of prognostic 
should be left unnoticed. The " ugly threatening appear- 



■) 



elements — atm os - 



pheric, celestial, oceanic, and (if in port) terrestrial signs 
of all kinds noted— such as the small white advancing 



I' 



cloud expanding into an arch, or the little white spot {huirs- 

lurid sky —remark- 








in the 




w 
5_-" 



ahle red colour of clouds and of other objects— bands of 



s 



light, and distant advancing walls of darkness— portion 
of cloud driven rapidly and irregularly— appearance of 
ascending lightning— peculiar aspect of stars or planets at 
uight, or of the sun or moon at rising or setting, and in 




what that peculiarity consists 



— whirlwinds, waterspouts (and 



r% 



r\ 



and peculiar veerings of wind with them, and alternations 
of calm— smgular rises and lulls of wind and moaning or 
roaring noises, and whether these are certainly/ in the 
atmosphere — phosphorescent sea— flight of bn-d 



^ - 



s, uneasi 



ness 



of animals— unusual abundance of certain fish. 
Meanwhile the movements of the barometer and the 
direction and force of the wind should be watched with 
unceasing vigilance. Hourly observations should be at 
once commenced, and the intervals diminished as it be- 
comes more and more certain that a storm is in progress. 
When fairly established, they cannot bo read too fre- 
quently, and every sudden rise or fall of the one, every 



shift of the other (as 



direction), should be noted 



of 



be read and noted to the minute, at every cntrj, made. 






^^ 



'tt 



-T^^i 



t 



•-s^ 



-J 



306 



METEOROLOGY 



[S«ct.. IX. 



During the continuance of tlie storm, and especially if 



there be reason (from its characters^ and its occurrence in 








'6 



cane, or *^^ cyclone,'' in the sense insisted on by Mr. 

Mr. Piddington, all the 



Redfield, Colonel Reid, and 
atmospheric appearauces and changes sliould be noted as 
frequently as possible, particularly at changes of the 
y/ind and in the calm centre of the vortex, should this 
unfortunately reach the ship. Flashes of light appearing 
in the barometer tube (not simply arising from oscillation) 
■thunder and lightning, particularly at shifts of the wind, 
and their relation to sudden discharges of hail or rain 
temperature of rain and of the sea — form and size of 



nailstones 



—whirlwinds or waterspouts occurring in the 
cyclone, their appearance, whirlings, tracks, size, &c.~- 
circles of light overhead in the centre of the gale, to be 
estimated or measured as to their anmilar diameter 



sun 



moon, or stars 



if seen, and if of peculiar brilliancy or 
culours— state of the sea as to regularity, rising, falling 



breaking, &c., particularly at the centre — veerings or oscil- 
lations of wind, and the exact intervals in which they occur 
moderating of the wind for an hour or two or more 



lid the state of 



after the gale has appeared to commence, « 
the instruments and sky at the time. An exact account 
should be kept of the vessel's coming up or felling off, 
and the log hove, if possible, to ascertain with the utmost 
care the ship's drift in lying to. Blasts of hot and cold 
air—extraordinary light and darkness. Whenever partial 



clear in 




Oi. UxKy 



sky affjrc 



ds an 0'- 



pportunity, pay particular 
attention to the direction of the upper scud. At the 
gomg off of the gale the same attention to ail the pheno- 






1 

i 



I 



f 



( 



a 

2 



tr 



h 



r 

) 







JS 




I 

r 

I 




* 



Sect. IX. 1 



METEOIiOLOGY. 



30? 



7 



mena as at its coming on. Obsei 



&c., to be continued at gradiially increasing intervals, 
and at length hourly till the usual state of things is fully 
restored— gradual rising of clouds at horizon or zenith 
and banks forming to be noted, and their altitudes mea- 
sured. The precise position of the ship before and after 
the gale to be carefully indicated, and all possible infor- 
mation to be collected of the manner, exact times, &c., in 
which other ships have been affected by it, a-d every 
endeavour used to trace out the path of the centre, the 
diameter of the vortex, and the direction of its revolution, 
by suT)sequent inquiry whenever opportunity may occur. 



or " cyclones,'* accordin 




Hurricanes, revolving storms, 
to the meteorologists above named (now fully estabhshed 
as true representations of fact), differ from mere local and 

of the regular atmospheric 



temporary exaggerations 



currents in this— that they are in the nature of vortices, 
or circulating movements participated in by masses of 
air of from 50 to 500 miles in diameter, revolving the 
more rapidly the nearer the centre, up to a certain dis- 
tance, or radius, tvithin which there is a calm. The place 
of this centre of rotation meanwhile advances steadily along 
a definite line upon the globe, with a velocity varying from 
2 to 30 or 40 miles per hour, and pursuing a track which 



5 



as 



has a singular fixity of geographical situation and geome- 
trical form. But the character which it is of most impor- 
tance to a seaman to know, and the knowledge of whicn 



as 



^ 



has repeatedly been the cause of catastrophes which might 
have been avoided, is this, viz. :— that in the same hemi- 



'"m^^ 



^-. 



308 



METEOKOLOGY. 



[Sect. IX. 



Sec 



-X 



*^ 



i 



'i 



^ 



_-T 



* 



! 



: 

H 

± 



sphere great cyclones alicaijs revolve the same way (so far 




at least as our present information extends), but that this 
direction is opposite in opposite hemispheres. In the 
northern hemisphere their rotation is retrograde^ i. e., con- 
trary to the motion of the hands of a watch laid face 
upwards, or in conformity with the motion of the hand in 
unscreii'ing a screw. In the southern, their rotation is 
direct^ conformable to the hands of a watch, or to the 
motion of the hand screwing m a screw into a horizontal 

. And this general fact affords the following simple 
rule by which to know at any given moment the hearing of 
the centre of the vortex, which is the point of extreme 
danger, by reason of the fury of the wind in its vicinity, 
its sudden reversal, and the terrible sea which prevails 
there. When sure that you are within the limits of a 
cyclone, stand erect and look full in the wind's eye, then, 
if in the northern hemisphere, turn yourself 90° or one 
quarter of the circle round to your right (if in the 
southern, as much to your left), and you will have the 
centre of the hurricane facing you. Thus, if in the 
northern hemisphere the wind at the ship be due north 
(blow/rom the nortli), the centre bears due east from the 
hip's place. 

The habitual tracks of hurricanes are but imperfectly 
known, and all which tends to throw light upon this 
part of the subject is of the last importance to navigation. 
The reader may consult the works of Mr. Redfield, 
Colonel Reid on the 'Law of Storms' (2nd edition) 






/' 



and 



s 



s ^T 



Hornbook for the Law of Storms,' 



by Mr. Piddington, a work full of interest and information 
on the subject, and which no navigator should go to sea 



I 



iin] 

as 

tra 

tra 

the 



ag] 



wii 



th( 



br( 



it 



s 



qu 



rei 
of 

sit 
ati 
po 



he 

tV' 



CO. 



[- 



V. ■ 

V 



%<' 






* 



Sect, IX.] 



METEOROLOGY. 



309 



unprovided with. The dii^ection of the ^ind after the 
complete passage of the hurricane is a point of interest, 



as indicating whether the " cyclone " consist in the bodily 



transfer of a given mass of rotating air, or in the successive 
transmission of a rotary movement from air to air in situ, 
the air in each point of its track being only transiently 
agitated. 



Winds. 



The points most important to remark respecting the 

wind are, 

1st. Its average intensity and general direction during 
the several portions of the day devoted to observation. 

2ndly. The hours of the day or niglit when it com- 
mences to blow from a calm, or subsides into one from a 

breeze. 

Srdly. The hours at which any remarkable changes of 

its direction take place. 

4thlv. The course which it takes in veering, and the 

quarter in which it ultimately settles. 

5thly. The usual course of periodical tvinds, or such as 



remarkably prevail during certain seasons, with the law 



> - 



of their diurnal progress, both as to direction and inten- 
sity : at what hours and by what degrees they commei 
attain their maximum, and subside ; 



1 AO 



and through what 



points of the compass they run in so doing. 



The 



of 



heights in the atmosphere, as indicated by the courses 
the clouds, in different strata. 

7thly. The times of settlng-in of remarkably hot or 
cold winds, the quarters from which they come, and their 



'+. 



1 



310 



METEOROLOGY. 



[Sect. IX. 



Sec 



! 



,^ 




X J 



courses, as connected with the progressive chancres in 
their tcinperature. 

8thly. The connexion of rainy, cloudy, or f^iir weather 
with the qnarter from which the wind blows, or has 
blown for some time previously. 

Several of these points of inquiry have especial refer- 
ence to land winds, and can only be duly studied in port 
or during residences on shore. In cruises along shore, 
or on arrival or depnrture, observe how far the influence 
of the land extends, and by what gradations the character 
of the winds changes from terrestrial to oceanic, especially 
with reference to the difference between the hours when 
the sun is above and when belov/ the horizon. 

Clouds and Fogs.~ThQ dissipation of cloud under the 
apparent influence of the full moon is a point to which 
attention has lately been called ; the state of the sky on 
the days and nights of the full moon, and those imme- 
diately preceding and following it, should be noted with a 
view to confirming or renting this connexion. Hourly 
observations, commencing before sunset, of the relative 
proportion of clear and clouded sky would be desirable. 

The height of the vapour plane is a datum of impor- 
tance, especially in tropical regions. At sea it is not easy 
o determine ; but when near a mountainous coast, where 
the clouds repose at definite levels on the hills, many 
opportunities may occur to ascertain it with precision. 
The lower level of unmelted snow may in such localities 
also be made a subject o+' inquiry. The average height 
of the vapour plane at sea under the equator is a mete- 
orological element of much interest. Opportunities cf 
determining it by measuring the apparent altitude of the 






flat 
isl 



for 
sh( 

res 
an( 

the 

ten 
air 
eve 

an( 
tha 



low 
the 



ma 



wai 
sho 



irrf 



the 

1 

( 

loft 

the 
sur 



and 
wit 

obj! 






fc- 



-.? 



} 






. 1 




r 



4 , 



^ * 



* t 



^1 



. it» 



I i 



rV 



■ 



U>'" 



1^ l' 



Sect. IX.l 



3IETEOROLOGY. 



311 



flat bases of cumular clouds from two ships wlsose distance 
is Ivnown, or otherwise, should be seized when they offer. 

suddenly clouds over, or when f-rgs 



When the 




form unexpectedly, the barometer and thermometer 
should be noted minutely, as such appearances often 
residt from, a rapid diminution of atmospheric pressure 
and consequent absorption of heat by the rarefaction of 






the air. Fogs prevailing at definite localities indicate 
temperature of the sea habitually exceeding that of the 
air. Thoy often also indicate the vicinity of ice. When- 
ever fogs are met with at sea, the temperature of the air 
and (^f the surface water should he recorded with more 

than usual care. 

Temperature of the 5t^a.~Shoals cast up water from a 
lower level to the surface where any current exists, and 
therefore a sudden change of temperature of the surface 
may indicate a shoaL In crossing currents coming from 
w^armer or colder latitudes^ the surface temperature 
should he especially attended to, and the maximum of 
irregularity due to the current watched for. Should 
opportunities offer of obtaining deep sea temperatures^ 
they should be eagerly seized. 

Observations in Port or in 



h..^ 



asccnam 




Teiyiporary Rei 
Shore. — Opportunities should not be lost of 
lofty eminences, and noting thereon the hygrornetrio and 
thermometric conditions corresponding to altitudes mea- 
sured by the portable barometer, or otherwise known. 

The temperatvire of deep wells should be ascertained, 
and that of the soil at different depths, which, if made 
with due care and under favourable circumstances, is an 
observation of very ^rreat interest. Excavations should 



% 



312 



o 



METEOROLOGY, 



m 



-i 



[Sect, IX. 



Le made in dry soil, and 7i7ider 
tvind. In winch should be buried 



/ 




at depths of three, six, 
and nine feet, thermometers well wrapped in woollen cloth, 
or in pots of pounded charcoal or even of dry sand, 
enclc^od in strong vessels to defend them from damage, 
and to prevent the possibility of change of temperature 
in extracting and reading them. The zero points of the 
thermometers should be most scrupulously ascertained, 
and their errors at the temperatures registered made a 
subject of special inquiry- The readings should be exact 
to tenths of degrees. Observations thus made under the 

in various longitudes with scientific precision^ 
might furnish data of the utmost value towards deter- 
mining tlie constancy or variability of the sun's radiation 
from year to year. If the thermometers cannot be spared, 
bottles of water similarly defended may be buried (or of 
brandy, if in frozen soil), and the temperature of the 
liquid taken immediately on raising them. In case of 
prolonged Bojourn this should be repc^vLoJ monthly. 

Some localities are remarkable for enormous tails of 
rain. Tlius it is stated on the authority of Captain 

that between the 1st and 24th of February, 
1820, there fell ticelvefeet seven inches of rain in the Isle 
of Cayenne.* In all such localities great attention should 
be paid to the rain gauge, and pains taken to procure 

from perfectly authentic registers containing 





instances of the kind^ and information respecting their 
attendant circumstances. In some geographical localities 
it is said never to cease raininar — in others* that rain never 




* Ed, Phil. Joura.j viii. 186, from Silllman's American Journal of 



Science^ iy. p. 375. 



Sect 



fall^ 
here 

take 

bette 
olle 



c 



cottc 

thes 
If ai 
terre 
mete 
Tl 
ofth 




nist, 
to a 
shou] 

M 

place 
enqni 



th 



eir 



comp 

level 

t^ansi 
the 



V 



ti'acei 



or 



pri 

Notice 
inflv 



le: 







ItB 



< 



^^ i 



. t 



f 






) 



1^ 



•V 



1 



l- 



\L 



V 



*fr» 



h 



« . 



i 



i 






r 



f 






J 



,i to 



i 



lit-: ft 




•J 1" 



>*" 



tii^k 



! 



n J 



* 



Sect. IX. 1 



J 



METEOROLOGY. 



Br 



O 



fall 






Local inquii-y and consultation of records must 



due care bein^ 



here stand in lieu of personal observation, 

taken to rely on none but unexceptionable evidence. 

The phenomena of dew are of more interest, and can be 
better studied on shore than at sea. The amount of dew 
collected by a given surface of any bibulous radiant, as 



cotton, &c., in clear nights, i 



rt 



perft 



the sky, and on the level of the soil, should be registered. 
If accompanied with ohservations of the depression of the 
terrestrial radiant thermometer, and also of the hv^Ti 



meter, such observations would acquire additional value. 

The temperature of the soil under the direct influence 
of the sun as indicated by a thermometer barely covered 
with dry earth, is an element of importance to the bota- 
nist, and may be recommended as an apt accompaniment 
to actinometric observations. The thermometer used 
should have a scale reading at least to 180" Fahr. 

Meteorological registers kept by persons of credit at 
places where the ship may remain or touch, should be 
enquired for and copied, or the originals procured, and 
the instruments with which they have been made carefully 
compared, and the height of their stations above the sea- 
level ascertained. 



JVaterspouts, BuWs-eije Squalls^ Whirlit 



The 



, and from 



transition from the mere eddy to the whirlwind 
the whirlwind to the waterspout {Trornhe), should be 
traced if possible. All circumstances from the first trace 
or prognostic to their final dissipation should be minutely 
noticed, especially the movements of the sea under their 
influence, and the direction of their rotation. At what 
distance is the whirling motion of the air perceptible? 
AVhat are the indications of the barometer durin"- their 



p 



i 



i 



\ 



t-" 



V _L 



_-"t--r* 



» 



I 






3U 



METEOROLOGV. 



[Sect. IX. 



approach and recess? Do any and what electrical phe- 
nomena accompany them ? Does the water really ascend 
along their axis, and to what height ? Is the water they 



discharge in "" bursting " fresh or salt ? Note its tem- 



perature. 



e 



every 



Showers of Dust or Ashes. — When they fell, preserv 
specimens and examine them microscopically, whether 
consisting of organized or mineral matter. Note 
ckTumstance, especially the direction of the wind, and 
whether an upper current differing in direction from the 
lower, exist. Geographical situation of the ship espe- 
cially to be exactly ascertained. Enquire for volcanic 
eruptions within a thousand miles of the place of their 
occurrence. 

Thunderstorms, Lightning, Firehalls, Sfc. — Note the 
quarter of the horizon where distant lightning unaccom- 
panied with thunder appears and the extent it embraces. 
Especially notice any appearance of forked lightning 
striking upimrds. In an actual thunderstorm espedally 
attend to the quantity of rain or hail that falls — its inter- 
mittences, and its correspondence or the contrary v/ith 
great bursts of lightning near at hand. Notice the appa- 
rent direction taken by the storm, with, or against the 
wind. Attend to the remarkable reversal in the direction 
of the wind winch often immedlatelv follows the cessation 
of a thunderstorm. Violent thunder and lightning in the 
immediate vicinity of the place of observation sometimes 

very rarely, take place without rain, or with very 
little. In such cases notice every particular with the 
utmost minuteness, and ascertain if possible whether the 
storm has been elsewhere attended with rain. Fireballs 
are st^.ted to have been occasionallv seen running along 



? 




o 



\K 



Se' 



th 



« 



th 

m 

th 

de 



wi 

ah 
mi 

(01 

CO] 

str 




li 



a 



mc 
th( 
do 
en^ 

for 

mt 



se? 
int 

acj 
ph 



« 



^h 



i 



Shi] 






1 1 



w 



r, ; 



^^ I 



A- 



k 



t 



u 



V h 



\ 



^1 



lu- 



or? 



r 



i' 



*> 



iUfl f • 



1 f 



i 



1 . \i 



i*- 



,1 



Sect- IX.] 



METEOROLOGY. 



315 



the surface of the sea, and so reaching, striking and 




on s 



hip 



appearances which have been 



Bilp- 

posed analogous to the electrical phenomenon termed 
the ffloiv discharge. Attend to every circumstance which 
may favour or oppose thi» idea—especially the height of 
the clouds at the time, and whether or no remarkablv 
depressed along the line taken by the fireball. 

Should the ship be struck by lightning, if furnished 
with Sir Snow Harris's conductors (which appear to afford 
almost complete security against serious damage), 




mine the 



.gneti 



(originally non-magnetic) fixed transversely across the 
copper conducting plates. Note any luminous appearance 
seen along the line of conduction. Immediately on the 
stroke, ascertain, by placing the hand on the conducting 
plate, whether it is in any degree heated. Notice pecu- 
liar noises, and endeavour to trace their origin, also the 
mode in which the lightning escapes from the ship, and 
the phenomena attending its escape.* If damage be 
done, describe minutely the sort of effects produced, and 
endeavour to trace the direction and character of the 



forces immediately productive of such 
mechanical. 



as are 



purely 



Ahuuspherk Eledricmj can hardly be well studied at 
sea, the masts, sails, and rigging acting as pcrpetuallv 
interfering conductors. Indeed it is said that, except in 
actual thunderstorms, no indications whatever of atmos- 



pheric electricity can be detected 



in the open ocean. 



iliip 



* For the infinitely varied wivs in -wIiI^k i- x.^ • ^ 

, , , -^ ^^'^J^ ^^^^"chhghtmngniav affect a suip 

when struck we recomn^end a perusal of Sir S. Harris's short Z 

interesting work Eemarkable Instances of the Protection of certain 
bh.ps from the Destructive Effects of Lightning, &c./ London, 1847. 



V 2 



f 






. T 



I 

I 

\ 

»' 

1 

i 
I 



I 



6 



16 



METEOROLOGY. 



[Sect. IX, 



S' 



This, however, should not be taken for granted, Bv 
going aloft the observer may put himself out of the reach 
of much of the interfering influence, taking with hix]) an 
electroscope and a common jointed fishing-rod, having a 
dass stick well varnished with shellac substituted for its 



smallest joint to project into the atmosphere. To the end 
of the glass must be fixed a metallic rod terminating in a 



point, or carrying a small brass lantern, in which a lamp 
is burning, and connected with the electroscope by means 
of a fine copper wire. The electroscope may be either 
Saussure's pith ball, or Singer's gold leaf electrometer, 
and when charged the nature of the electricity m.ay he 



tested by excited glass or sealing wax. 



Auroral Phen 



All 



uch should be 



minutely 

registered, and all their phases, especially the formation, 
extent, situation, movement and disappearance of arches, 
or any definite patches or banks of light. An acquaint- 
ance with the principal stars of the constellations is neces- 
sary to observe such phenomena with effect, and the 
observer will do well to provide himself for the purpost^ 
with planispheres, on wdiich only the more conspicuous 
stars are indicated, w^ith their allineations. The exact 



time (true at least to the nearest minute) of any such 
definite body of light being centrally on any known star 
should be observed, as a means (by the aid of correspond- 
ing observations) of determining its real situation and 




The slovv drifting motion of such masses (in 
north latitudes generally southward — query if the reverse 
in south ?) should be specially attended to. Pulsations, 
like waves of light, rushing up from the horizon, should 
be also particularly remarked, and any appearance of 
patches of dejinite forms rendered visible hy such pulsations 



a 



n 
c< 

IX 



K^ 



h 
oi 

w 
ta 

al 

of 
be 
iir 



ai] 



op 

wi 



no 
ca: 
se: 
me 
of 



tl 



\( 



cl 



c 



to 

coj 

bej 

an( 

ttia 
ser 



■J 



'•'■.,ii> 



n 



J 



-r 



Sect. IX.] 



MITEOROLOGY. 



,n 1 / 



as it traverses them, but not otherwise appearing as lumi 



nous masses, particularly noticed. When arches or any 
considerable well-defined cloud-like masses are formed, 
mark on the chart their situation and extent amone the 
stars at several noted epochs of time, particularizing the 
brightest portions ; observe also tlie point of convergence 
of stn^amers and the formation of the corona, the ceniral 
point or focus of which should be projected on the chart 
vnth all possible exactness, and the time of so doing exactly 
taken, so as to determine by subsequent calculation its 
altitude and azimuth. Any indication of the near vicinity 
of auroral phenomena, or of their existence at a level 
belov.^ that of ordinary clouds, should be most minutely 
investigated at the moment, and carefully and circum- 



The connexion, if any, 



bet 



ween 



II 



stantially recorded. 

auroral masses and cirrous clouds should be traced 
opportunity occur. Note also the meteors if remarkable 
wdthin the auroral region. 

Ilalos, parhelia, mock suits, and other luminous phe- 
nomena of the kind, should be noted, delineated 



Wit 




care if complicated, and their dimensions measured with a 
sextant, or otherwise, by bringing the limb of the sun or 
moon (noting which limb) in contact with the two edges 
of the phenomenon in succession. Their colours also and 
their order should be described. 



Light cirro-stratus 



cloud in the neighbourhood of the sun has been observed 
to be bordered with three fringes of pink and green 



colours following the outline of the cloud. This rare and 



b...utiful phenomenon if seen should be most particularly 
and carefully described. Perhaps in some climates it 
may be of not unfrcquent occurrence. Unusual tints ob- 
served in the sky should be noted, and should that ex- 






"^ 

"? 

'i 




I 



*-'^ 






.-^ 



01 Q 



METEOROLOGY. 



[Sect. IX. 



tremely rare phenomenon 



f 



pale blue colour^ so little luminons as to allow of bemo" 
gazed at with impunity* — occur, the atmospheric circum- 
stances sliould be carefuUv recorded. 

The polarization of the light of the sky should be ex- 
amined habitually with a polariscope, and the relation of 
the points of maximum polarization to the suUj and the 
ob 



fc-^^\-^ 



m various 



, er's zenith, noticed in every variety of climate, and 

ing apparently 




of 



the sky, and 




abnormal recorded. 



Zocl 



Mai light. — In the seasons of its appearance take 
every opportunity in tropical climates to ascertain with 



« • 



preci SI 



on th 



e place of its apex among the stars, its breadth 



and degree of brightness, and %vhether variable or not. 



Meteors. 




1, Astronomy— Appendix. 



APPENDIX. 



Table I,~Correction to be added to Baroci " rs for Capillary Action. 



! Diameter of Tabe 



t 

U 



Correction for 



i 

Unboiled Tuoes. ! "l Boiled Tubes. 



Inch. 

0-60 



• 50 



1 




Inch. 

0*004 

0-007 





n 











« 



010 

ou 

020 
028 
040 
060 

088 



0O42 



Inch. 

0-002 

• 003 
0-005 

0-007 
0-010 
0-014 
0*020 
0-029 
0-044 
0*070 



* It occurred at Bermuda on the i2tli and ISdi of August, 1831, two 

days after the great Barnadocs hurricane of that year. 



ipP--1 






I 




I 

2 

3 

4 
5 
C 
7 

9 

10 

11 

12 

13 

16 
17 
18 
19 
20 

22 
23 
24 
25 

27 

28 

29 
30 

31 
32 

33 



I V 



■C 







•0 








1 « 





I'O 
^•0 



ro; 

I'O: 
•0; 

•0' 

-0; 

•0: 
•0; 
•0; 

t 

rO 

'0 



^ . 



-0 

•0 
•0 
•0' 



•Oi 
!'0 



34 ho: 



35 
36 
37 



■0. 

'o: 



n. c 



38 i.Q* 
40 

41 

42 
43 

44 
45 

46 

47 

48 
49 

50 



I'O; 
!'0; 

1 ^A< 






"■a 

j'O^ 

'0^ 

*0. 



I 



I 



^ J 



t.l 



I 



1 



i 



/ 




^ 



V 



App.] 



METEOROLOGY. 



91 G 



I 



Table II.— Correction to be applied to Ba^'omcters with Brms Scales, 
extending from the Cistern to the tup of the Mcrcarial Columii, to re- 
duce the observation to 32^^ Fahrenheit. 



Cm 


I K 


C XI 


E S. 










i 

i 


Tern 


24 

F 


24-5 


OK. 

1 


25-5 ! 26 ! 26-5 27 
+ ! -f 4- 1 + 


J 

2to 


■ 28 


i 

' 28-5 j 29 


1 

29-5 30 

1 


30-5 1 31 




1 

C 

) 




+ 


4- , -f 


^ 4- 


4- 

P 


\ -h -1- 1 ^- 


4- 


o 


i*0t51 


•063 


•064 -065 067 ^0C8 


•069 


•071 |-072 


•073 


•074 


;'076 !-07: ;-078 I'Obo 


i 


I i059 


.-061 1 


■062 '063 i-064 j'065 |-0G7 


•068 -009 


•071 ■•072 


^■'^73 l'074 !-076 ''077 


t 

^^^ 

1 


2 I'OjT '058 


■060 -061 -06^ '-003 ^064 


•066 ,-067 


:-06S I -009 


i-o;o 


•072 i-07;-; ^ = 074 


2 


3 '05o 


•056 


-057 !'05:= '060 ;-06i -062 


•im ^064 


•065 j 067 1 


1 

i 068 

1 


•069 :-07O l'07i 


i 


4 -053 


•054 


•055 1 


-056 j-057 i-05S -059 


■061 TCS 


'063 '-064 i 


\-0$5 


• 066 


•067 1-068 




5 ;-051 


•052 


053 


•054 I-055 h056 -057 


•058 fO.-.O 


: 060 i-061 


' ' 062 


•003 -065 1'066 


;5 


€ '-040 


050 


•051 ^052 '053 i-054 1 


•055 


•056 l'057 


1-058 !m)59 


: • 060 


•061 r0i^2 -063 


1 

6 


7 ,-04G 


•047 -048 !-049 


'050 i'051 


•052 


•053 h054 


I 055 i-056 


•057 . 


•058 h059 l-oeo ^ 


1 7 


8 -044 


•045 1*046 I '047 


•048 i'049 -050 


•051 |-052 


1^053 I' 054 


054 


•055 h056 1-05" ■ 


1 

S 


9 i'042 1-043 i 044 |-<M5 


•046 -046 i-047 


Oils -OiO 


r050 j-051 


•052 !-053 r054 1-054 1 


9 


10 


•040 -0^11 '04^3 ; t .^ 

1 ' 


•033 


•044 i-045 

j 


•046 -047 

] 1 


'047 !'048 
1 


•049 r050 


•051 1*052 


10 


11 -OSS ;-039 -039 


•040 


•041 


•042 '042 |-043 |-044 


•045 


•046 


■•046 !-047 


•048 !-049 i 


1 
1 

U 


12 


•036 -036 


■037 ! 


■038 


• 039 


•039 --O^- l04I '042 


'042 |-043 


:m)44 '045 -045 -046 '. 


12 


13 '033 -034 


•035 


•0"" -036 


• 037 


•0^8 


•038 '039 


■040 -040 


i-041 ^042 '043 


■043 


VS 


14 '031 •':32 


'(»33 


•033 


•034 -035 


•O0i> -03^; '■x.3'7 


i'037 -038 


:-038 i-039 1-040 i-040 ^ 


1 -1 


J5 


•029 -030 


•030 


•031 


'032 -032 1 


• 033 


•033 i-034 

■ 


! • 035 • 035 


•036 1 


-036 I-037 -038 ' 


15 


\G 


•027 ■02'^^ '-028 


'029 


•029 -030 -030 


•031 -032 


i ' 032 


•033 


I '033 i 


'034 * 034 


•035 


16 


\7 


•025 -025 


' 026 


•026 


•027 -027 


' 028 ' 


•028 i-029 : 


j-030 -030 ] 


•031 1=031 1-032 


•032 


17 


IB 


•023 


■0^23 


•024 


•024 


•02- '-025 


•025 


•026 ^-026 ■■ 


I-027 :-027 


•028 ^023 :-029 


■ • 029 


iS 


19 


•021 


■021 


•021 1-022 


'022 i-023 


•023 


•024 ;*024 1 

J 1 


•024 025 ! 


-025 -026 i'026 "027 : 


i9 


20 


'018 


•019 


'019 -020 '020 


•020 


•021 


•021 


•021 


'022 

! 


'022 i 

1 


■02;:^ '023 '023 


■024 

1 1 




2\ 1-016 


■017 


•017 


1 

017 


•ois 


•018 


■ous 


•019 -019 


{ 

"019 


■ 

•020 


1 ' 

•020 -020 1-021 i'021 


■ 21 




,'014 '014 


•015 ^^>io \ 


•015 


•016 


•016 


•016 r016 


•017 


■017 


•017 -018 i'OiS 1 018 


22 


23 


•^^^2 |"0i2 


•012 


•013 


•013 


-013 •OIS i 


•014 -014 


^•014 -014 


•Oio |'015 |-015 015 


^ 23 


24 


•Olu i^OlO 


•010 


'010 


•Oil 


•Oil 


•Oil 


•Oil 


•on 


•012 -012 


•012 i'012 1012 -013 


: 24 


2o 


■•008 


■ors -008 


•008 


: • 008 


•008 


•009 


■009 


•009 


•009 


■009 1 


•009 1*009 rOiO •oio 


25 


26 


•005 


= 006 


OOG 


•0U6 


! ' 006 


• 006 


•006 


•006 :-006 


1^006 i-OO'T ' 


'007 h007 1-007 


•007 


26 


27 '0U3 


■ 003 


•003 


•003 


•004 


•004 


•004 


■004 ■•(H')4 


■004 i'0O4 '■ 


•004 h004 1-004 


•004 


27 


28 


•001 ; 

1 


•GUI 

1 


•OOl -001 


•001 


•001 


•001 


>00i I'OOi 

! i i 


•001 j'OOi 


• 001 


•001 


•001 


•001 ■ 


*w5 


29 


•001 


•001 '' 


•001 -001 ' 


•001 


■ 001 


■001 -001 ■. 


■001 


r 

I'OOl l-ooi ^ 


• '>< j I 


'001 


-001 I'OOl 


29 


30 


•003 


• 003 


•003 


■004 


•004 


1 

•004 

1 


•004 


'004 '004 

1 


>004 1-004 i 

1 ! 


01)4 -004 -004 i'0G4 • 

F 
I 


1 30 

1 


31 k)05 


oot; 


•006 


•006 -006 


•006 


•006 


1 

•006 -006 


i 

,-006 1 007 


i 1 ! 

•Oo7 N07 '007 1-007 1 


31 


32 


•008 


•008 


■ 008 


•008 -OOS 


•008 


•008 


•009 -009 


■■009 -009 1 


'0*)^ '009 


'010 i-010 


32 


33 hOlO 


'010 


•010 


•010 1-011 


'Oil 


•Oil 


■Oil 'Oil i 


;-012 im:- ■ 


-0i2 -012 


•012 1-012 


33 


34 -012 


•012 


•012 


•013 '013 


•013 


•013 


'014 i-014 1 


•014 1-014 


•015 •OIS 


■015 


•015 


34 


35 •014 


•014 


•015 


•015 -015 


•015 


•016 1 


•016 i-016 ' 


•017 !'0i7 \ 


•017 -^'18 


■018 


•Oio 


35 


36 -016 


•017 


•017 -017 


■017 


•018 


•018 |-019 S-019 


^*019 |'020 


•020 i'020 -021 1-021 


; 36 


37 -013 


•019 


-019 -019 


•020 


•020 


•021 1-021 h02i 


•022 1*022 


•022 1*023 '023 -024 




38 M)20 

J-^ J" 1. ■-_ r""^ J— M. 


•021 


•021 


•022 


•022 


•023 


•023 


•02s ,024 


■02't ^-025 


•025 i-026 '026 i'0;=!6 


'^'^ 


39 i-023 


•0-23 


•024 


•024 


•024 


•025 ; ■ '2d 


•026 !'026 


•02: ;-027 


028 -028 ^029 1-029 


39 


40 ■ 025 


-025 


•026 


■026 


•027 


'027 


•028 *028 *029 


'029 -030 


■030 -031 '031 -032 

i 


40 


41 


•027 


•027 


•028 


•029 


*U29 


•030 


•030 -031 


1 

i'031 


4 

•032 :'033 i 


•033 :'034 


•034 


• 035 


r 

41 


42 


•029 


•030 i'030 


•031 


•031 




•033 f-033 -034 


•034 |-03" 


•036 i-036 1*037 


•037 


i 42 


43 


•0."1 


•032 -032 


•033 


•034 


•034 


'035 i'036 ,-036 


•037 ''038 


i-038 j-039 i-OlO 


•040 


43 


44 


•033 


•034 


•035 


'035 


•036 


•037 1-037 


•038 -039 


|-04() -040 


!*U41 1-042 -042 


-043 


A.i 


4o j*i>;ir> 


• 036 


■ 037 


•038 


•038 


•039 ' 


•040 


'041 '041 


•042 -043 


•044 1 = 044 i'045 -046 


* ^^ 


46 j'03S 


•038 

1 y^L ^ -« 


' 039 


•040 


041 


•042 


■042 


•043 ^044 


■•045 '045 


'04i! '047 !'04b r-: ... 


4fi 


47 


•04U ''U-il 


■041 '042 


•043 

1 


•044 !-045 


•046 i-046 


•047 


•048 


-049 h050 ;-05i 


•051 




48 

4 /^ 


'042 ;-043 


•044 r045 -045 

X y^ I . . r 


•046 '-047 ;-048 '-049 


'050 


'051 


-052 '•052 '=053 i'054 


; 48 


49 


•0-i4 (j45 


•046 


•047 

ma. ^k 


•048 1-049 


'050 ; O'O 1-051 


•052 


• 05;', 


•054 ^-055 ;-056 -057 




oo 


•04b '04/ 


"048 


•049 


•05 J '^ox 


■052 


•053 


;-054 

p 


'055 -OoC 


; 057 ;-058 ^-059 -060 


^ 50 

t 
1 



^ 



'^ i 



1 
4. 



i 



I 



i 




METEORGLOG/, 



fApp, 



Taj^Le IL-^Co7itiniced. 



Oh 



C H 




24 24-5 



25%". 



^0 I ^ 


51 i'048 


52 


•050 


53 


•053 


54 


•055 


53 1 


•057 


60 ; 


•059 


57 1 


•061 


58 


•063 


59 i'0G5 


60 : 


•068 



h ft 



{•049 

i'052 
054 

058 
060 
i*062 

;-067 

:"GG9 



•074 
'076 
•07s 
■080 
•083 

■ • 087 
• 089 

•091 
•093 



'071 
•073 
■07(? 
•078 

'080 
■ 082 



. ■ 050 
1*053 
)-055 

■*057 
:*l»59 
i'06i 
I • C64 
:-066 
i'OGB 
OTO 

•073 

I -075 

: • 077 
-079 
-0S2 
•0 



;(r5 






4 ;-086 



'ilO 



'086 
•089 
■091 

• 093 

•095 

!-09r 

i ■ 099 
•102 
•104 
•106 
■108 
•110 
'113 



j'093 

'095 

I • 097 

•099 

•102 

1-104 

i'i06 
i-108 
h]]0 
'113 
'115 



i*051 
^•054 
!-056 

1-058 
i-060 
I 063 

■'0C5 
• 067 
' 070 

•072 

•074 
•076 

•079 

•081 

'-083 

r085 

•088 

1-090 

•092 

'095 

■097 
•099 
'iOl 
•104 



•075 

•078 
•080 
•082 

■085 

•087 

-089 
•092 
•094 
•096 



i • 009 
•101 



•053 

•056 

1-058 

i-060 

063 

065 

I -068 

•070 

r072 

75 



j-077 

i-079 

i'082 

j ■ 084 

1-086 
[•089 

{•09i 

•094 



•054 

^057 
'059 
•062 
•064 
i-066 
! • 069 
I '071 
■ 074 
I -076 

I 

I -073 
•081 

' 083 
'086 
•088 
•090 
•093 
I -095 
i-09S 
■'JOG 



102 




•103 



' * 



-055 
■053 
'060 
'063 
'065 
■ 068 
'070 
•073 
!^075 
•077 



I ' 080 
I • 082 
- 085 
• 087 
' 090 
•092 
095 
•097 
•100 
•102 



•066 



'087 



• 059 
•062 

•065 
•067 
'070 
•073 
•075 
•078 
i-080 
^•083 

i ' 086 

•088 
•091 

'094 
•096 

• 099 
•102 
•104 
•107 
•109 



30-5 



i'I07 



t^ 



9 



•110 

'113 
•115 



n^r^ 



^ 



n 






1*126 
i'129 

hl31 



• 136 



o 



1 Q I 
1 tjO 






o 



J 



r^~ 



i-I33 
1-135 

I -137 

i'139 
;m41 

•144 

i']50 
!'152 
'•155 



[•133 
ri35 
i'137 
i'l40 



^129 
*131 



123 



■115 

■'117 
•120 
'122 
•125 
•128 
• i 30 
•133 
•136 



• 087 
•090 
•093 
•095 
•098 
•101 
•103 

• 1 06 
•109 
■ill 



•114 



•061 
•064 
•067 
•070 

i-072 
1*075 
•078 
•081 
•083 
•086 

•089 
•091 
'094 

• 097 
1*100 
•102 
•105 
•108 

•liu 

hiia 



•0G2 
•005 
•068 
•071 

'073 

•076 
•079 
•U82 
■085 
087 



•J20 j 72 

.TOO "'o 



i • 



143 



i * 



* 



fr 



142 

144 
147 



^ * 



150 
153 

1 •^ - 



\ ♦ 



I * 



JA> 



J 100 

_ _ _» _ 



165 
167 



167 
170 
172 



1-178 



I 4 



« ^1- 



-^ 



162 



197 1100 



A 






T 



] 



] 
] 
] 
1 
1 



T, 



\ 



App.] 



METEOROLOGY. 



S21 



■^ 



Table III. — Elastic Force of Aqueous Vapour for every Degree of 

Teoiperature, from C^ to 103^ Fahreulieit. 





Temp. 
Fahr. 




Fcrce. 
Inches of 
Mercury. 


I 

Temp. 

Fahr. 


Force. 
Inches of . 
Mercurv. 


ji Temp, 
Fahr. 

o 


Force. 
Inches of 

Mercury, 

1 


1 

Temp. 

Fahr. 

o 


1 For'*?. 

Inches of 
Mercury. 


^ 


















0-051 


26 


0-147 


'52 


0-389 


78 


0-942 




1 


0-053 


27 


0-153 


53 

F 


0-402 


79 


973 




2 


0'056 


28 


0-159 


54 


0-417 


i 80 


j 1-005 




3 


0-058 


29 

p 


0-165 


55 


0-432 


81 


j 1-036 




1 

4 


0-060 


30 


0-172 


56 


0-447 


82 


1-072 




5 


0-063 


31 


0-179 


^ 57 


0'4G3 


83 


1-106 




6 


0-066 


32 


0-186 


58 


0-480 


84 


1*142 




7 


1 0-069 : 


33 

1 


0-193 


59 


0-497 j 


85 


1-179 




8 


071 


1 ^^ 


0-200 


60 


0-514 


86 , 


1-217 




9 


0-074 


35 


0-208 


61 


0-532 


1 ^* 


1 1-256 




10 


0-078 


36 


0-216 


62 


0-551 


88 


1-296 




11 


0-081 


37 


0-224 


63 


0-570 

1 


89 


1-337 




12 

p 


0-084 


38 


0-233 


64 


0-590 


90 


1-380 


b 


13 


0'088 


39 

i 


0-242 


65 


0-611 


91 


1-423 




14 


0-092 


40 


0-251 i 

1 


1 66 

1 


0-632 


92 


1-468 




15 


0-095 


41 


0-260 i 


0/ 


0-654 

j 


93 1 


1-514 




16 


0-099 i 


42 


0'270 


68 


0-676 i 


1 94 


1*562 


-. 


17 


0-103 


43 


280 


69 


0-699 , 


95 


1-610 




18 


0-107 


44 


0'291 


70 


0-723 I 


96 


1-GOO 


t 


19 


0-112 


45 


0-302 


71 


0-748 


97 


1-712 




20 


0-116 


46 


0-313 


72 


0*773 


98 


1-764 




21 


0-121 


47 


0-324 


73 


0-799 


99 


1-819 




22 


0-126 


48 1 


0-336 


74 


0-826 


100 


1-874 




23 


0-131 


49 I 


0-349 


75 


0-854 


101 


1-931 




24 


0-136 


50 


0'361 

1 


76 


0-882 


102 


1-990 


1 


25 


0-142 


51 


0-375 j 


77 


0-911 


103 


2-050 



b- 



HW 






,v= 



y 



Table IV.— Showing the force of the Wind on a square foot for different 

heights of the Coiumn of Water in Lind's Wind-gauge. 



Height of 
the Column 
of Water. 



Force of the 
Wind in Avoir- 
dupois Pound 



s. 



Inches, 

12 
11 
10 

9 

8 

7 
6 



62-5 

57-29 
52-08 
46-87 
44-66 
36-55 
31-75 



Height of 

the Column 

of Water. 



Force of the 
Wind in Avoir- 
dupois Pounds. 



Inches. 

5 
4 

3 
2 

1 

0-5 
0-1 

0-05 




26-04 

20-83 
15-62 
10-42 
5*21 
2-60 
0-52 
0*26 



p 3 




^-----^.---.^'i^^' 



322 



METEOROLOGY, 



[App. 



Table V. — Showing the Factors by which the Results of Actinometer 
Observations have to be Multiplied, to reduce them to a constant dilata- 
bility of the enclosed "Blue Liquid, viz., that at 60*^ Fahr, 



."* - 



Iiifernal 


4 

Reducing 


rnternal 


Keducins j 


i Internal 


J Reducing 


Internal 


Reducing 
Fact(tr. 


Tiler, 


^ Factor. 

L 

T 


Ther. 

1 ! 

IT 


Factor. 

i 


1 

'I'her. 


1 Factor. 


: Tiier. 


O 


i 
a 
1 

1 
1 


i 1 









1 o 


30 


1 2-888 j 


G3 


0*943 


\ 96 


0-642 


129 


0-550 


SI 


2-713 


64 


0-925 


i 97 


0-638 


130 


0-549 


32 


2 •862 

1 


65 


0-908 


98 
99 

1 


0-634 


131 


0-547 


33 


1 2-430 

1 M 


66 


1 0*892 


0-630 


132 


0'545 


34 


2-312 1 


0/ 


i 0-877 


\ 100 


0-626 


133 


0-543 


35 


2 '205 


68 


1 0*862 


101 


0-622 


134 


0-541 


36 


1 2-106 


69 


0-849 


102 


0-618 


^ 135 


• 540 


37 


j 2-014 


70 


0-837 


103 


1 0-615 


136 


- 538 


38 


1 " 930 


71 


0-826 


104 


\ 0-612 


137 


0-536 


39 


1*853 


72 


0*815 


105 


0-609 


138 i 


0-535 


40 


1-781 


73 


0-805 


106 


0-606 


139 1 

1 


* 533 


41 


1-715 


■ 1 

i 74 


0*795 


107 


0-603 


140 


0»532 


42 1 


1-654 j 

h 1 


75 


= 785 


108 


0*600 


141 


0-530 ' 


43 

1 


1*597 


76 


■ 0-775 


109 


0-597 


142 


0-528 


44 


1 • 543 ! 


77 


■ 0*766 


110 


0*594 


143 


0*527 


45 


1*492 


78 


0*757 


111 


0-591 

1 


144 


0*525 


46 


1 • 443 


79 


0*748 


112 


0*588 


145 


0-524 


47 


1*397 j 


80 


0-739 


113 


0*586 


146 


0-522 


48 

i 


1*353 


81 


0^731 


114 


0-583 


147 


0-521 


49 i 

1 


1-312 


82 


0-723 


115 


0-581 


148 


0-519 


50 


1-274 


83 


0-716 


116 


0-578 


149 


0-518 


51 


1-239 


84 


0-709 1 


117 


0-576 


150 


0-517 \ 


52 


1-206 


85 


0-702 


118 


0-573 


151 


0-515 


53 t 


1-175 


1 86 


0-695 


119 1 


0-571 


152 


0-514 


54 


1-147 


87 


0-689 


120 


0-569 


153 


0-513 


1 

55 ' 


1-120 


'' 88 1 


0-683 


121 


0*566 


154 


0-512 


56 ' 

r 


1*094 


89 


0-677 i 


122 1 


0-564 


155 


0-511 


57 ! 

4 


1-069 


90 


0-671 


123 


0-562 


156 

F 


0-509 


58 i 


i'045 


91 


0-666 


124 


0-560 


157 


0*508 


59 1 


1-022 


92 1 


0*661 


125 ^ 


0-558 


158 


0-507 i 


60 : 

E 

F 


1 - 000 


93 1 


0"65G 


126 i 


0-556 


159 


0-506 / 
0-505 


61 i 

F 


0*980 


94 


0-651 


127 1 


0=554 


160 


62 I 

1 


0-961 

w t 

L 1 

1! 


95 

3 


0-646 


i 128 1 

i 

1 


0-552 























r 



'^i 



Sect. X.] 



( 






23 ) 



"'^f, 



»'4 



-■ '4 



Section X. 



ON ATMOSPHEE 






WAVES AND 



BAEOMETKIC CUEYE 




I 






.1 



Mi 



i'. 



By WILLIAM RADCLIFF BIET, Esq. 

In sketching out a system of barometric observation 



having especial reference to the acquisition of data from 



which the barometric character of certain large are 






01 



f 



the sm^face of the globe may bo determined — inasmuch 
as such areas are distina:uished from each other, on the 

O 

one hand by consisting of extensive spaces of the oceanic 



surface unbroken, or scarcely broken, by land; on the 
other by the proximity of such oceanic surface to large 
masses of land, and these masses presenting two essentially 
different features, the one consisting of land particularly 
characterized as continental, the other as insular, regard 

lias been accordingly had to such distribution of land and 
water. 

As these instructions are intended for officers in Her 
Majesty's and the mercantile service, observations on kuul 
have not been alluded to ; but in order that the data 
accumulated may possess that value which is essential for 
carrying on the inquiry in reference to atmospheric waves 
and barometric curves with success, provision is made to 
mark out more distinctly the barometric effects of the 
junction of large masses of land and water. It is well 



.■^^ 



324 



^ 



ON ATMOSPHERIC WAVES 



[Sect. X. 



r 



i 



1 






i 

J 



i 



known tliat the oceanic surface, and even the smaller 
surfaces of inland seas, produce decided inflexions of the 
isothermal lines. They exercise an important influence 
on temperature. It has also been shown that the neio-li- 



5 



boiirhood of water has a very considerable influence m 
increasing the oscillations of the mercurial column in the 
barometer, and in the great systems of European undula- 
tions it is well known that these oscillations increase espe- 
cially towards the north-west. The converse of this 
however, has not yet been subjected to observation ; there 
has been no systematic co-operation of observers for the 
purpose of determining the barometric aifections of large 
masses of water, such as the central portion of the basin 
of the northern Atlantic, the portion of oceanic surface 
between the Cape of Good Hope and Cape Horn, the 
Indian and Southern oceans, and the vast basin of the 
Pacific. Nor are we yet acquainted with the character 
of the oscillations, whether increasing or decreasin^y, as 
we recede from the central portions of the oceanic surfaces 
we have mentioned towards the land which forms their 
eastern, western, or northern boundaries. This influei 
of the junction line of land and water, so fiir as it is yet 

known, lias been kept in view in framinc these instructions, 
and 



*.^ij 



? 



as it appears so prominently in Europe, it is hoped 



that additional observati 



ons betv/een the four dailv read- 



ings * to which probably many observers may habitually 
restrict themselves, making on certain occasions and in 
particular localities a series of observations at intervals of 
three hours, will not be considered too frequent when the 
reat importance of the problem to be solved is fully 

* See p. 271, 




V 






I 



O 



di 



y 



t 



f 



Sect. X.] 



AND BAROMETRIC CURVES. 



825 



•V' 



r^ 



K 



J 
. I 



, 1 



1 c*1 



.f 



■o 



apprehended. It need scarcely be said that the value of 
these observations at three-hourly intervals will be greatly 
increased by the number of observers co-operating in 
them. Upon such an extensive system of co-operation a 
large space on the earth's surface, possessing peculiarities 
wliich distinguish it from others extremely unlike it in 
their general character, or assimilate it to such as possess 
with it many features in common, is marked out heiow 
for particular observation, occupying more than two-tiurds 
of a zone in the northern hemisphere, having a breadth of 
40", and including every possible variety of terrestrial 
and aqueous surface, from the burning sands of the great 
African desert, situated about the centre-, to the narrow 
strip of land connecting the two Americas on the one side, 
and the chain of islands connecting China and Hindostan 
with Australia on the other. On each side of the African 
continent we have spaces of open sea between 30'' and 
40^ west longitude north of the equator, and between 60' 
and 80^ east longitude, in or to the south of the equator, 
admirably suited for contrasting the barometric affections, 
as manifested in these spaces of open water, with those 
occurring in situations where the influence of the terrestrial 
surface comes into more active operation. 

The localities where three-hourly readings are chiefly 
desirable may be specified under the heads of Northern 
Atlantic, Southern Atlantic, Indian and Southern Ocean 



^\ 



Paciji 



*5 



Noriheru Atlantic. Homeward-hound Voyages. —The. 
discussion of observations made in the United Kingdom 
and the western border of central Europe, has indicated 



r 



^ 

i 



326 



ON ATMOSPHERIC WAVES 



[Sect. X. 



that off the nortli-west of vScotland a centre of great 
barometric disturbance exists. This centre of disturbance 
appears to be considerably removed from the usual tracks 
of vessels crossing the Atlantic ; nevertheless some light 
may be thrown on the barometric phsenomena resultino" 
from this disturbance by observations during homeward- 
bound voyageSj especially after the vessels have passed the 



^ r\n 



meridian of 50 
Baffin and Hud 



west longitude 



Voyagers to or from 



't5 



of the voyage to read off the barometer every three hours, 
as their tracks would approach nearest the centre of dis- 
turbance in question. Before crossing the 50th meridian, 



the undulations arising from the distribution of land and 



water m the uei'jiibourhood of these vast inland seas 
w^ould receive considerable elucidation from the shorter 



intervals of observation, and after passing the 50th meridian 



the extent of undulation, as compared with that observed 
by the more southerly vessels, would be more distinctly 
marked by the three-hourlv series. Surveying vrreh 



coasts of Ireland and 



stationed on the north-western 
Scotland may contribute most important information on 
this head by a regular, and as far as circumstances will 
allow, an uninterrupted series cither of six-hourly or 
three-hourly ol.servations. The intervals of observation 
on board vessels stationed at the Western Isles, the 
Orkneys, and the Shetland Isles, ought not to be longer 
than three hours, principally on account of the great ex- 
tent of oscillation observed in those localities. Vessels 
arriving from all parts of the world as they approach the 
United Kingdom should observe at shorter intervals than 
IX hours. As a general instruction on this head the 



I 



I 



h 

I 



r 



I 



t 

f 



r 

) 



'\ 



I 



Sect. X.] 



AND BAR03IETRIC CURVES. 



OZ g 



"^ 



series of tliree-hourly observations may be commenced on 
board vessels from America and the Pacific by tbe way 
of Cape Horn on their passing the 20th meridian, such 
three-hourly observations to be continued until the arrival 



of the vessels in port. 



Cap 



Good Hope should commence the three-hourly series 
either on leaving or passing the colony, in order tliat the 
phsenomena of the tropical depression hereafter to be 
noticed may be well observed. 



%. 



"j^ 






^ -y 



■}i 



:.\\ 



i^ 



* .f 



Northern Atlantic. 
sailing to the United 



7 T 



Oviimrd-bound y 




States^ Mexico, and tne 



+v 



es:;:ls 
West 

Indies, should observe at three hours' interval upon pass- 
ing the 60th meridian. Observations at this interval, on 
board vessels naviofatins the Gulf of Mexico and the 



Caribbean Sea, will be particularly valuable in deter- 
mining the extent of oscillation as influenced by the 
masses of land and water in this portion of the torrid 
zone, as compared with the oscillation noticed oft the 
western coast of Africa, hereafter to be referred to. 



^ » 



Southern Atlantic. Outward and homeicard hound. 
Without doubt the most interesting pbsenomenon, and one 
that lies at the root of the great atmospheric movements, 
especially those proceeding northwards in the northern 
hemisphere and southwards in the south^.n, is the equa- 
torial depression first noticed by Von Humboldt and con- 
firmed by many observers since. We shall find the general 
expression of this most important meteorological fact in tlie 
Report of the Committee of Physics and Meteorology, 
appointed by the Royal Society in 1840, as folio ws 










f^iSE: 



€ 



328 



ON ATMOSPHERIC WAVES 



[Sect. X 



" The barometer, at the level of the sea, does not indicate 
a mean atmospheric pressure of equal amount in all parts 
of the earth ; but on the contrary the equatorial pressure 
is uniformly less in its mean amount than at and beyond 
the tropics/' Vessels that are outward bound should 
upon passing 40** north latitude, commence the series of 




o- 



L 

4 



s 



three-hourly observations, with an especial reference to 
the equatorial depression. These three-hourly observa- 
tions should be continued until the latitude of 40" south 
has been passed : the whole series will then include the 
minimum of the depression and the two maxima or apices 
forming its boundaries. (See Daniell's ' Metcorol 
Essays,' 3rd edition.) In passages across the equator 
should the ships be delayed by calms, opportunities should 
be embraced for observing this depression with greater 
precision by means of hourli/ readings ; and these readings 
will not only be valuable as respects the depression nere 
spoken of, but will go far to indicate the character of any 
disturbance that may arise, and point out, as nearly a 
such observations will allow, the precise time when such 
disturbance produced its effects in the neighbourhood of 
tlie ships. In point of fact they will clearly illustrate the 
diversion of the tendency to rise, spoken of in the Report 
before aJbided to, as resulting in ascending columns and 



s 



sheets, between which wind flaws, capricious in their 
direction and intensity, and often amounting to sharp 
squalls, mark out the course of tlieir feeders and the 
indraft of cooler tiir from a distance to supply their void. 
Hourly observations, with especial reference to this and the 
following head of enquiry, should also be made off the west- 
ern coast of Africa during the homeward-bound V0y..2;e. 



f 



I 



I 



i 



Sect. X.] 



AND BAROMETBIC CURVES. 



3 




9 



* ^A 



> V 






4 



u -"■-'•■■ 



,* 



i' 



.^d 



Ixiimediately connected witli this part of the outward- 
bound voyage, hourly observations, as often as circum 
stances will permit, while the ships are saihng from the 
Madeiras to the equator, will be extremely valuable in 



elucidating the origin of the great system of south- 






westerly atmospheric wave^ that traverse Europe, and in 
furnishing data for comparison with the amount of oscilla- 
tion and other barometric phsenomena in the Gulf of 
Mexico and the Caribbean Sea, a portion of the torrid 
zone essentially different in its configuration and in the 
relations of its area to land and. water, as contra- 

J* 

distinguished to the northern portion of the African 
continent ; and these hourly observations are the more 
desirable as the vessels may approach the land. They 
mny be discontinued on passing the equator, and the 
three-hourly series resumed. 

Tlicre are two points in the southern hemisnhere 



4 



between 80^ west longitude, and 30° east longitude, that 
claim particular attention in a barometric point of view% 
viz,. Cape Horn and the Cape of Good Hope ; the laiM^. 
is within the area marked out for the three-hourly obser- 
vations, and too much attention cannot be paid to the 
indications of the barometer as vessels are approaching or 
leaving the Cape. The northern part of the South 
Atlantic Ocean has been termed the true Pacijic Ocean of 



the ivorld ; and at St, Helena a gale was scarcely ever 
known ; it is also said to be entirely free from actual 
storms (Col. Reid's 'Law of Storms,' 1st edition, p. 415). 
It may therefore Le expected that the barometer 
present in this locality but a small oscillation, and ships 
in sailing from St. Helena to the Cape will do well to 




y. 



* 



J^ 



330 



ON ATMOSPHERIC WAVES 



[Sect. X. 



ascertain, l)y means of the three-hourly observations, the 
increase of oscillation as they approach the Cape. The 
same thing will hold good with regard to Cape Horn : it 
appears from ])revious observation that a permanent 



barometric depression exists in this locality, most pro- 
bulny in some way connected with the immense depression 
noticed by Captain Sir James Clark Ross, towards the 



Antarctic Circle. The general character of the atmos- 
phere off Cape Horn is also extremely different from its 
character at St. Helena. It would therefore he well for 
vessels sailing into the Pacific by Cape Horn, to continue 
the three-hourly observations until the 90th meridian is 
passed. 

Before quitting the Atlantic Ocuc... it may be well to 
notice the marmc stations mentioned in my Third Report 
on Atmospheric Waves,* as being particularly suitable for 
testing the views advanced in that report and for tracing 
a wave of the south-westerly s) stem from the most western 
point of Africa to the extreme north of Europe. A series 
of hourly observations off the western coast of Africa has 
already been suggested. Vessels staying at Cape Verd 



Islands should not omit to make observations at three 



circumstances will 
Canaries, Madeiras 
should be made. 



'3 



alloWj hourly readings. At the 

and the Azores, similar observations 

Vessels touching at Cape Cantin, 



^ V. ^^. .iici,-^^7. vt;?<bei« loucnmg at i^ape uantm, 

Tangier, Gibraltar, Cadiz, Lisbon, Oporto, Corunna, and 
Brest, should also make these observations while they are 
in the localities of these ports. At the Scilly Isles we 



Keports of the British Association for the Adyaneement of Science, 
184:0, p. 139. 



* 



f 



Sect. X.j 



AND BAEOMETilTC CURVES. 




31 



rr 






*,^ 



^! 



P 



y * ^ 

iW 



i 



under the snperin- 



have six-hourly observations, made 

tendence of the Honourable the Corporation of the Trinity 



H 



Shi] 



)s in nearmor 



tl 






islands and niakins* the 



observations already pointed orit, will greatly assist in 
determining the increase of osciilation proc 




ceding 
of the two CTeat European 




ward from the nodal point 
systems. We have already mentioned the service siirvey- 
ing vessels employed on the coasts of Ireland and Scotland 
may render, and the remaining portion of the area marked 
out in the report may be occupied by vessels nayigatm 




Nor 



Ham 



merfest. 

In connection with these observations, having especial 
reference to the European system of south-w^esterly atmos- 
pheric waves, the Mediterranean presents a surface of con- 
siderable interest both as regards these particular waves, 
and the influence its waters exert in modifving tLv. » wo 
great systems of central Europe, The late Professor 

r 

Daniell has shown from the Mannheim observations, that 
small undulations, having their origin on the northern 
borders of the Mediterx^anean^ have propagated themselves 
northward, and in this manner, but in a smaller degree, 
the waters of the Mediterranean have contributed to 
increase the oscillation as well as the larger surface of thi 



' i 



northern Atlantic. In most of the localities of this great 
inland sea six-hourly observations may suffice for this 
immediate purpose ; but in sailing from Lisbon through 
the Straits of Gibraltar, in the neighbourhood of Sicily 
and Italy, and in the Grecian Archipelago, we should 






scries, as 



marking more 



a-' 



recommend the three-hourl 

distinctly the effects resulting from the proximity of kind ; 



■ 






\Jm\ 



ATMOSPHERIC WAVES 



[Sect X. 



this reriicark has especial reference to the passage throuo-h 
the Straits of Gibraltar, where, if possible^ hourly obser- 
vations should be made. 



a, or Australia, observ?4ons at 



The Indiajiand Southern Oceans. Outward and home- 
ward bound. — On sailing from the Cape of Good Hope 
to the East Indies, Chin 
intervals of three hours should be made until the 40th 
meridian east is passed (homeward-bound vessels should 
commence the three-hourly readings on arriving at this 



meridian). Upon leaving the 40th meridian the six- 
hourly observations may be resumed on board vessels 
bound for the Indies and China, until they arrive at the 
equator, when the readings should again be made at 
intervals of three hours, and continued until the arrival 
of the vessels in port. 



With regard to vessels bound for 



New 



^ 



^^ 



be continued from the 4utJi to the 100th meridian, and 
upon the vessels passing the latter, the three-hourly read- 
ings siiould be com-menced and continued until the vessels 
arrive in port. Vessels navigating the Archipelago, 
between China and New Zealand, should make observa- 



X X- ^ 



tions 



s 



5 



every three hours, in order that the undulation 
arising from the configuration of the terrestrial and 
oceanic surfaces may be more distinctly marked and more 
advantageously compared with the Gulf of Mexico, the 
Caribbean Sea, and the northern portion of the African 
continent. 



lite Pacific Ocean. — As this ocean presents so vast an 
aqueous surface, generally speaking observations at in- 



I 
\ 



\ 



\ 






^<- 



tei 
its 

ap 
or 

ho 
efl 

th> 

su 

th^ 



1 



re. 
he 

ID: 

N 

bo 

th. 

re 

fo 



cc 



m 
tr 



di 

ol 
tl 
ei 
bi 



1 



ij 



vi 



v 



Sect. XO 



AND BAROMETRIC CURTES. 



333 



•^ 



■! 



^ w^i^ *"A 






f'.!<(\ 



i. 



tervals of six hours will be amply sufficient to ascertain 

*.ls, however, on 



its leading barometric phsenomena, 

approaching the continents of North and South America 

or sailing across the equator, should resort to the 




hourly readings, in order to ascertain more distinctly the 
effect of the neighbourhood of land on the oscillations of 
the barometer, as generally observed, over so immense a 
surface of water in the one case, and the phienomena of 
the equatorial depression in the other : the same remarks 
relative to the latter subject, which we offered under the 
head of South Atlantic, will equally apply in the present 
instance. The configuration of the western shores of 
North America renders it difficult to determine the precise 
boundary where the three-hourly series should commence ; 
the 90th meridian is recommended for the boundary as 
regards South America, and from this a judgment may be 
formed as to where the three-hourly observations should 
commence in reference to North America. 






■ \ 



r'r 



r^-^: 

c^?^ 



t- - 



In the previous sketch of the localities for the more 
important observations, it will be seen that within the 
tropics tliere are three which demand the greatest regard. 

I. The Archipelago between the two Americas, more 
particularly comprised within the 40th and 1 20th meri- 
dians west longitude, and the equator and the 40th degi'ee 
of north latitude. As a general principle wo should say 
that vessels within this area should observe the barometer 
every three hours. Its eastern portion includes the lower 
branches of the storm paths, and on this account is pecu- 
liarly interesting, especially in a barometric point of 



t- 



View. 



t' 



334 



ox ATMOSPHERIC WAVES 



' [Sect. X. 



Sec 



II. The Norf hern portion of the African Contineiit^ in- 
cluding the Sahara or Great Desert. — This vast radiating 
surface must exert considerable influence on the waters 
on each side northern Africa. Vessels 



sailin 



area comprised between 40^ west and 70° east and the 
equator and the 40th parallel, should also make observa- 
tions at intervals of three hours. 




III. The great Eastern Archipelago. 
somewhat similar character to the western ; like that, it 



presents .i 



is the region of terrific hurricanes, and it becomes a most 



interesting object to determine its barometric phenomena ; 



the three-hourly system of observation may therefore be 
resorted to within an area comprised between the 70th 
and 140th meridians, and the equator and the 40th 
deoTec of north latitude. 



n 



The southern hemisphere also presents three important 
localities, the prolongations of the three tropical areas. 
It is unnecessary to enlarge upon these, as ample instruc- 
tions have been already 




iven. 



^^ 



may, however, 



remark, with regard to Australia, that three-hourly 
observations should be made within the area comprised 
between the lOOth and 190th meridians east, and the 
equator and the 50th parallel south, and hourly ones in 
the immediate neighbourhood of all its coasts. 




, HUKRICANES, AND TyPHOOIsS. 

The solution of the question— How far and in what 
manner are storms connected with atmospheric waves ?— 
m.ust be extremely interesting to every one engaged in 
either the naval or merchant service. It is foreign to the 
purpose of these instructions to enter into any examina- 



f 






tio 

oh 
■f 



c 



no 

w i 1 

wi' 
thi 
he; 



an^ 



tai 
ani 
th( 
un 

M 
17 
'I 

tli 

2, 

Wi 

all 
of 

or 

of 

St( 



tl 



^i 



pa 

tic 
re 

Sl( 



Bh 



> * 



Sect. X.l 



AND BAROMETRIC CURTES, 



335 



*X;-i^" 



**,-.. 




I 1 

4 

■■,ft 



1 . ■ 



I' 



t 

1-; 



jt' 



tion of the views that exist on this head. Our great 
object here will be to endeavour to mark out such a line 
cf observation as appears most capable of throwing lights 
not only on the most important desiderata as connected 
with storms, but also their connection or non-connection 

with atmospheric waves. We shall accordingly arrange 
this portion of the instructions under the following 



heads: — D 



Localities ; Maroi 



Preceding 



jf Pressure. 



n 



The most important desiderata apper- 
taining to the subject of storms, are certainly their origin 
and termination. Of these initial and terminal points In 

e absolutely know^ nothing, 

if a round form observed \^ 

Judith and Esther, in lat. 



great 



the 



Mr. Seymour on board 
17° 19' north and long. 52 



o 



( 



CoL Reid's 



65), may be regarded 



as 



the commencement of the Anti 




ugu 



2, 1837. This vessel was the most eastern of those from 
which observations had been obtained: and it is th 



Lxiw 






absence of contemporaneous observations to the eastward 
of the 50th meridian that leaves the question as to the 
origin of the ^^'est Indian revolving storms unsolved. 
Not one of Mr. Redfield's storm routes extends eastward 
of the 50th meridian ; this at once marks out, so far as 
storms are concerned, the entire space included between 
the 20th and 50th meridians, the equator, and the 60th 
parallel, as a most suitable area for observations, under par- 
ticular circumstances hereafter to be noticed, with especial 
reference either to the commencement or termination of 
storms, or the prolongation of Mr. Redfield's storm paths. 









t-- . 



K 







m- 












ri- 

■-J 















ON ATMOSPHERIC WAVES 



[Sect. X. 



Sect 



Localities. — The three principal localities of storms 
are as follows: — I. The western portion of the basin of 



the North Atlantic ; II. The China Sea and B 



ay of 




Bengal; and III The Indian Ocean, more particularly 
in the neighbournood of Mauritius. The first two have 
already been marked out as areas for the three-hourly 
ohservations ; to the latter, the remark as to extra ob- 
servations under the head of Desiderata will apply. 

Mr. Redfield has shown that on some occa- 
sions storms have heen preceded by an unusual pressure 
of the atmosphere ; the barometer has stood remarkably 
hlgh^ and it has hence been inferred that there has ex- 
isted around the gale an accumulation of air formino* a 
margin ; barometers placed under this margin indicating 
a much greater pressure than the mean of the respective 



localities. 



With regard to ih^ West Indian and Ame- 



rican hurricanes — any considerable increase of pressure, 
especially within the space marked out to the eastward 
of the 50th meridian, will demand immediate attention. 



Upon the barometer ranfrino- 



-"! 



very high within this 
space, three-hourly observatioiis should be immediately 
resorted to ; and if possible, hourly readings taken, and 
this is thp more important the nearer the vessel mav be 
to the oOth meridian. Each observation of the baro- 
meter should be accompanied by an observation of the 



vf'ivA — its direction should 



be most carefully noted, and 



4 



the force estimated according to the scale in p. 300, or 
by the anemometer. It would be as well at the time 
to project the barometric readings in a curve even of a 
rough cluaracter, that the extent of fall after the mer- 
cury had passed its maximum might be readily discernible 



by 

rep 
2or 

pui 
nea 
po: 

att( 
cha 

win 
duc 



s 



ho 



bar 
ere; 

stor 
the 
inci 
kee 
thei 
mai 

by 

vatJ 
con 
(otl 
kee 
CHr 
ter: 

has 
son 
tJie 
a St 



I ! 



Sect. X.] 



AND BAEOMETRIC CURVES. 



3P^ 



* 



I 



t 1-ilx 



1 i 



1 



f 



•^. -' 



V 



1 . 



r J 



i 

V 



f 



-^ 



by the eye. A paper ruled in squares, the vertical lines 
representing the commencement of hours, and the auri- 
zontal tenths of an inch, would be quite sufficient for this 
purpose. The force of the wind should be noted at, or as 
near to the time of the passage of the maximum 
possible. Durir 



tf^ rt 




the fall of the mercury particular 
attention should be paid to the manner in which the wind 
changes, should any change be observed ; and should the 
wind continue blowing steadily in one direction, but gra- 
dually increasing in force, then such increments of force 
should be most carefully noted. During the fall of the 
barometer, should the changes of the wind and Its in- 
creasing force indicate the neighbourhood of a revolvino- 



torm, (independent 



-S 



the focu 



o 

o 



) 



reasons for avoiding 



to 



increase our knowledge of these dangerous vorticos 
keep as near as possible to their margins as to approach 
their centres. The recess from the centre towards the 
margin of the storm, will probably be rendered apparent 
by the rising of the mercury, and so far as the obser- 
vations may be considered valuable for elucidating the 
connection of atm.ospheric waves with rotatorv storms 
(other motives being balanced), it might be desirable to 

margin— provided she is not 



V" 



keep the ship near the 



c^irried beyond the influence of the winds which charac- 
terize the latter half of the storm— until the barometer 
has nearly attained its usual elevation. By this means 
some^ notion might be formed of the generaf direction of 
die nne of barometric pressure preceding or succeeding 
a storm. 



Should a gale be observed commencing withou 







? 



Q 



- % 



338 



ON ATMOSPHERIC WAVES 



[Sect. X. 



liavin^ been preceded by an unusual elevation of tlie 
mercurial column, and consequently no additional obser- 

made ; wben the force of the wind is 



een 



ration have b 
noted in the usual observations at or above 5, then the 

series should be resorted to, and the same 



_^ 



tliree-hmirly S( 

care taken in noting the direction, changes, and force of 

the wind as pointed out in the preceding paragraph. 

The foregoing remarks relate especially to the central 
and western nortions of the North Atlantic ; they will 
however equally apply to the remaining localities of 
storms. Under any circumstances, and in any locality, 
a Mf/h barometer not less than a low one should demand 
particular attention, and if possible, houriT/ readings taken 
some time before and after the passage of the maximum : 
this will be referred to more particularly under the next 




Preceding and Succeeding Accumulations of Pressure. 
Mr. Redfield has shown in his Memoir of the Cuba Hur- 



ricane oi Oc 



f 



tober, 1844, that two associated storms were 
immediately preceded by a barometric wave, or accumu- 



lation of pressure, the barometer rising above the usual 



or annual mean. We have just referred to the import- 
ance of hourly observations on occasions of the readings 
being high as capable of illustrating tlie marginal phe- 
nomena of storms, and in connection with these accumu- 
lations of pressure in advance of storms we woidd reiterate 



the suggestion. These strips of accumulated pressure are 



doubtl 






crests of atmospheric waves rolling forward 



s. 



In some cases a ship in its progress may cut them trans- 
versely in a direction at right angles to their lengthy m 
others very obliquely ; but m all cases, whatever section 



. i 



I 



pT 



fi 



i 



] 



^ 
K 



Sect. X.J 



AND BAR03IETRIC CURVES. 






"H 






■ 



y 

^ 



--1 






.rt 



1 



' I'i 



■ ; . 



-f 



r 



i^ 



may be given by tbe curve representing the observations 



too much attention cannot be bestowed on the barometer, 
the wet and dry bulb thermometer, the direction and force 
of the wind, the state of the sky, and the appearance of the 
ocean during the ship's passage through such an accumu- 
lation of pressure. When the barometer attains its mean 
altitude, and is rapidly rising above it in any locality, 
then hourly observations of the instruments and pheno- 
mena above noticed should be commenced and continued 
until after the mercury had attained its highest point and 
had sunk again to its mean state. In such observations 
particular attention should be paid to the direction and 
force of the wind preceding the barometric maximum 
and the same phenomena succeeding it, and particular 
notice should be taken of the time when, and amount of 
any change either in the direction or force of the wind. 
It is by such observations as these, carried on with great 



care and made at every accessible portion of the oceanic 
surface, that we may be able to ascertain the continuity 
of these atmospheric waves, to determine somewhat re- 
specting their length, to show the character of their con- 
nection with the rotatory storm, and to deduce the direction 
and rate of their progress. 



Seasons for extra Observations. 

In reference to certain desiderata that have presented 
themselves in the course of my rpsearches on this subject 
(see Report of the British Association for the Advance- 
ment of Science, 1846, p. 163), the phases of the larger 
barometric undulations, and the types of .the various 
reasons of the year, demand particular attention and call 

Q 2 



v**!"^^^- :*.■¥-' 



:^?E;'*^H*^?'-i==^ 



^ 



310 



ON ATMOSPHERIC WAVES 



[Sect. X, 



for extra observations at certain seasons : of these^ three 
only have yet been ascertained — the type for the middle of 
Novem])er — the annual depression on or about the 28th of 
November — and the annual elevation on or about the 25th 
of December. The enunciation of the first is as under : 



" That during fourteen days in November, more or less 



- ^ 



equally disposed about the middle of the month, the oscil- 
lations of the barometer exhibit a remarkably symmetrical 
character, that is to say, the fall succeeding the transit of 
the maximum or the highest reading is to a great extent 
similar to the preceding rise. This rise and fall is not 
coiitimious or unbroken ; in some cases it consists o^five, 
in others of three distinct elevations. The complete rise 
and fall has been termed the great symmetrical baro- 
metric wave of November. At its setting in the baro- 
meter is generally low, sometimes below twenty-nine 
inches. This depression is generally succeeded by two 
\^ ell-marked undulations, varying from one to two days m 
duration. The central undulation, which also forms the 
apex of the gretit wave, is of larger extent, occupying 
from three to five days ; when this has passed, two smaller 
imdulations corresponding to those at the commencement 
of the wave make their appearance, and at the close of 
the last the w^ave terminates." With but sHght excep- 
tions, the observations of eight successive years have 
confirmed the senera 



correctness of this type. On two 



occasions the central apex has not been the highest, 
and these deviations, with others of a minor character, 
form the exceptions alluded to. This type only has 
reference to London and the south-eastern parts of 
England ; proceeding westw^ard, north-westward, and 



) 



^ 



\ 



*^^ 



s 



^ ' 



• u, 



'-aJ 



! 



- I 



i( 



l 



\. 



1, iCt, 



■ tf 



I'' 



Sect. X.] 



A.ND BAROMETRIC CURVES. 



341 



Sr, 



northward, the symmetricaJ character of this type 
considerably departed from ; each locality possessing its 
own type of the barometric movement dm'hjg !No.^mber. 
The desiderata in immediate connection with the No- 
vember movements, as observed In the southern and 
south-eastern parts of England, that present themselves, 
are — the determination of the type^^ for November, espe- 
cially its middle portion, as exhibited on the oceanic 
surface within an area comprised between the SOtli and 
60th parallels, and the 1st and 40th meridians west. 
Vessels sailing M'ithin this area may contribute greatly to 



the determination of these types by making observation 



tt 

.k^ 



at intervals of thn^e liours from the 1st of November to 
the 7th or 8th of December. The entire period of the 
great symmetrical wave of November will mtist probably 



as 



the annual depression of the 28th. For the elevation 
of the 25th of December the three-hourly observations 
should be commenced on the 21st, and continued until 
the 3rd or 4th of the succeeding January. 

With respect to the gi*eat wave of November, our 
knowledge of it would be much increased by such a series 
of observations as mentioned above, being made on board 
surveying and other vessels employed off Scotland and 
Ireland ; vessels navigating the North oea ; 



^-^"'MS 




I 



sta- 
tioned off the coasts of France, Spain, Portugal, and th; 



e 



northern parts of Africa, and at all our stations in the 
Mediterranean. In this way the area of examJnation 



would be greatly enlarged, and 



diff. 



curves more fully elucidated ; and this extended aica of 
observation is the more desirable, as there is some reason 



I J -r 



*^ 



342 



ON ATrviOSFHERIC WAVES^ ETC 



[Sect. X. 



grea 



similar character. althou2:h 



est symmetry revolves 
around a fixed point, most probably the nodal point of 
the great European systems. 

It is highly probable that movements of a somewhat 

presenting very different 
curves, exist in the southern hemisphere. The November 
wave is more or less associated with stoi^ms. It hvs been 
generally preceded by a high barometer and succeeded 
by a low one, and this low state of the barometer has 
been accompanied by stormy weather. We are there- 




prepared 



to 




fb 






imilar phenomena in the 



southern hemisphere, in those localities which present 
similar states of weather, and at seasons when such wea- 
ther predominates. We have already marked out the 
two capes in the Southern hemisphere for three-hourly 
observations : they must doubtless possess very peculiar 



o 



as 



area of the Southern Ocean. It is highly probable that 
the oscillations, especially at some seasons, are very con- 
siderable, and vessels visiting them at such seasons would 
do well to record with especial care the indications of the 
instruments already alluded to. At present we know hut 
little of the barometric movements in the Southern hemi- 
sphere, and e\v,ry addition to our knowledoje in this 



respect will open the way to more important conclusions. 



/ 



^ ^ 



.i^jj 



^ 

J 



Sect. XI.] 



343 



^i 



^^ 



^k 



TL 



• ■ -. 



■■< 



iilV 



^.i 



^ 1 



> > 



.< - 



*^ 



**: 






Section XL 



z o o L o G Y. 



RTCHAUD 



C^:; -xwji^pi*" 



C*ll 



F 

Instructions f 07' Collecting and Preserving Animah. 
As water is the element in wliicli the greater number of 
the classes of animals exist, and as the sea is the scene of 
such existence and the field of research which will be 
most commonly presented to those for whom the following 



instructions for collecting and preserving animals have 



been drawn up, they will commence with the marine 
species and the lowest forms of animal life* ^ 

Alg^i, Sponges, Corallines, and Corals. 



The 



the vegetable and 



animal kingdoms is so obscurely marked in the lowly 
organized marine species, and the modes of collecting and 



preserving these are so similar, that the kindred group 



above-named are associated together as the subjects of 

the following remarks. 

Alg(B^ commonly called sea-weeds, may be divided, for 

the convenience of the collector, into three kinds, according 
to their colour : 

1. Olive-coloured {Fuci) ; generally of large size and 
leathery texture, rarely gelatinous ; usually laminate or 
leafy 5 rarely filamentous or thready. 




44 



ZOOLOGY. 



[S«5Ct. XI. 



Floridece) 



usually filamentous, sometimes membranaceous. 



gelatinous ; 



3. Green 



■) ; membranaceous or fila 



mcntous ; rarely liorny. 

Sponges are bodies usually adherent in irregular or 
amorphous masses, rarely in the form of hollow reticulate 
cones ; composed of a soft, jelly-like tissue, supported by 
siliceous or calcareous spicules, or by horny filaments. 



Thev 



" siliceous.' 



and 



(( 



calcareous" sponges. Their soft 



organic substance is commonly diffluent, and drops from 
the firmer basis when removed from the water, or it is 
easily washed away. It exhibits no sign of sensibility : no 
contraction or retraction when touched or otherwise stimu- 
lated. The evidence of life is afforded, as in the coral- 
lines and algae, by the flow of currents of water through 
canals, entering by pores, and in the sponges escaping by 
larger orifices ; and an appearance of animal life is given 
to botii alg« and sponges by the locomotion of the 
sporules or gemmule 






Corallines are plants coated with a calcareous covering 



either red or green when fresh, becomJng white and brittle 
on exposure to the air. 

Corals, though called " zoophytes," are true animals ; 
the currents which permeate them enter by " mouths," 
always provided with a crown of feelers or seizers, called 
tentacles, and communicating with digestive sacs or '' sto- 
machs," into which the pores of the nutrient canals open. 
The tentaculated mouths are called " polypes." Their 



fle 



L^ 



til em toge- 



ther into an organic whole when the coral is compound or 



; 



■t 

i 



Sect. XI.] 



ZOOLOGY. 




45 



i^^ 



'o^ 



U 



1^ 



s 



'I 



rV 



1 



M 

f 

H 



k- ; 



'1 



r 



' ^ 



has more than one mouth, is " sensitive/ or retracts and 
shrinks when touched. For the purposes of the collector 
corals may be divided into the '* fleshy " (Polypi carnosCp 
in which the flesh has no firm supporting part ; the 
" horny '' or " flexible," usually having this supporting 
substance as an external tube ; and the ^^ calcareous," in 
which the supporting substance is usually covered by the 
animal matter or flesh, forming an internal skeleton, 



usually of one piece, rarely jointed. 

The above-defined classes of organized beings, whi^^h 
all present the ^* habit ' ^ or outward form, more or less, 
of plan^^. are found from the extreme of high-water mark 
to the depth of from 50 to 100 fathoms. Living algae 
rarely descend below 50 fathoms, but corals of the 
genera Lepralia^ Retepora^ and Tlomera have been 
dredged up from 270 fathoms, and fragments of dead 
coral from 400 fathoms.* Specimens within the reach of 
the tide are to be collected at low water, especially of 
spring tides : the most interesting species occur at the 
verge of low-water mark. Those that dwell at greater 
depths must be sought by dredging, or by dragging after 
a boat an iron cross furnished with 
hooks. One or more stron 



numerous strong 




?^la 

o 



bottles 



with wide 



mouths, or a hand-besket lined with japanned tin, should 
be provided for the purpose of bringing on board the 
smaller and more delicate species in sea-water, and tliev 



should be kept in it, the 



Fioridecd'^ more especially, 



r 

until they can be arranged for drying, or other modes of 
pcrraancnt preservation can he attended to. 

In collecting alg;o, corallines, or the branched, liorny, 

* Capt- Sir James C. Ross, ' Antarctic Vojage,' Appendix, No. IV. 

Q 3 




f J 



m- 





?^ 



■"^- 



f- 



^**^_ 



_ T 



346 



ZOOLOGY. 



[Sect. XI. 



or calcareous corals, care should be taken to bring the 
entire specimen with its hasc or root. With respect to the 
coarser algae, it is merely requisite, for the purpose of 
traiisraission, to spread the specimens immediately on 
being brought fresh from the sea, without previous wash- 
ing, in an airy situation to dry, but not to expose them 
to too powerful a sun : if turned over a few times they 
will dry very rapidly. When thoroughly dried they may 
be packed loosely in paper bags or boxes, and will require 
only to be re-moistened and properly pressed, in order to 



delic^ote algae : 



i4 r 



r 

i 



make cabinet specimens. For the purpose of transmission 
it is better pM to wash the specimens in fresh-water pre- 
vious to drying, as the salt they contain tends both to 
preserve them and to keep ih^m pliable, and more ready 
to imbibe water on re-immersion. With respect to the 

The collector should have two or three 
flat dishes, one of which is to be filled with salt water and 
two with fresh ; in the first of these the specimens are to 
be rinsed and pruned, to get rid of any dirt or parasites, 
or other extraneous matter ; they are then to be floated 
in one of the dish es of fresh water for a few minutes, care 
beifig taken not to leave them too long in this medium, 
and then one by one removed to the third dish, and a 
piece of white paper, of the size suited to that of each 
specimen, is to be introduced underneath it. The paper 
is to be carefully brought to the surface of tlie water, the 
specimen rcmainliig displayed upon it, with the help of a 
pair of forceps or a porcupine's quill, or any fine-pointed 
instrument ; and it is then to Le gently drawn out of the 
water, keeping the specimen dis]>layed. These wet 
papers, with their specimens, are then placed between 



Sect. XL] 



ZOOLOGY. 



S47 






<<b. « 



>.i 



^ J. 



1 



1 



• i 



I 



^ 



- *A 



^ ■/ 



f A 



I. 



^.-.i" 



tH' 



^' 



^^' 



sheets of soft soaking-paper, and put mider presBure, and 



in most cases the specimen adheres in drying to the paper 
on which it is laid out. Care must be taken to prevent 
the blotting-paper sticking to the specimens and destroy- 
ing them. Frequent changes of drying-paper (once in six 
hours), and cotton rags laid over the specimensj are the 
best preservatives. The collector should have at hand 
four or five dozen pieces of unglazed thin calico (such as 
sells for 2d. or 3(L per yard), each piece about eighteen 
inches long and twelve inches wide, one of which, with 
two or three sheets of paper, should be laid over every 
sheet of specimens as it is put in the press. These 
cloths are only required in the first two or three changes 



of drying-papers ; for, once the specimen has begun 



to dry, it will adhere to the paper on whicii it has 
been floated in preference to the blotting-paj^r laid 

over it.''* 

For dried specimens of corallines, corals, and sponges,, 
it is advisable to soak the specimen for a time in feesli 
water before drying. They may then be packed amon 
the rough-dried sea-weeds in boxes ; but the more deli- 
cate specimens should be placed in &c>>^-ate chip-boxes. 
with cotton. 

With regard to corals, etc., it must be remembered that 
dried specimens are but the skeletons of those animals. 







and that only the "horny" and "calcareous" s|3ecie 

be so preserved. The " fleshy " kinds, comrnonly 

nal- 



can 



" sea- anemones," 



known as " polypes," 

flowers," must be preserved entire in alcohol or sahne 

Dr. Harvey, in Mr. Ball's ' Report ou the Dublin Universitv Mu, 
seum,' p. 3. 



-V 



( 






''48 



jU 



OOLOGY. 



[Sect. XL 



solution, and of the latter the following (No, I 
Goadby's recipes) has been found successful : 



of 



Solution No. I, 



Bay salt . 



4 oz. 



Alum • . . 2 oz. 



Corrosive sublimate 
Raiu- water « 



2 grains 
1 quart. 



In order to preserve the specimens expanded they 
should be removed and placed alive in a dish of sea- 
Avater; and when they have protruded and expanded 
their tentacles, the solution should be slowly and quietly 
added to the sea-water, when the animal may be killed 
and fixed in its expanded state. So prepared, the speci* 
mens should be transferred to a bottle of iresh solution. 

In like manner the minute polypes of the flexible or 
horny corals may be preserved protruded from their cells 



s 



and expanded. If a small piece of corrosive sublimate i 
put into the vessel of sea-water containing such livina* 



polypes, it will kili or paralyse them when protruded, as 
it slowly dissolves ; but they must be removed as soon as 
they have lost their power of retraction, otherwise their 
tissue is rendered fragile or is decomposed. The polypes 
or animal part of the calcareous kinds, called " madre- 






pores," " millepores," " fungire," " red coral," 
goniffi," &c., require for their preservation, ni connec- 
tion with their supporting basis, the following solution 

(No. II.) I'- 



SOLITTION No. IT, 



Bay salt • . . 

Arsenious acid, or .rhite oxide of arsenic 
Corrosire sublimate ...... 

Boilini4 rs^: \fater 



lb. 
20 grains 



DS. 



2 grai 
1 quart. 



# 



All the pol}^es concerned in the formation of coral- 



r 



- ^ 



I, 



Sect. XL] 



ZOOLOGY. 



349 



4 



v^- 



^ H 



I. 



reefs, atolls, or coral-islands, may be preserved m the 
above solution, provided they be killed by its gradual 



application as above described, and be afterwards trans 
ferred into fresh solution. With regard to the structure 
and formation and mode of observation of coral islands 
and reefs, the work by Charles Darwin, Esq., On the 
Structure and Distribution of Coral Reefs (8vo., 1842), 
should be consulted.* Never fail to ascertain, if possible, 
to what depth below the surface of the sea the corals 
descend, and on what basis they rest ; and for particular 



instructions with reference to coral reefs, see 




Bar 



win's 



remarks under the head of ' Geology.' 




« 



(i; 



Lt; 



-J . 



v-- 



If 



Infusorial Animalcules {PoJyijoMria, P olythalawia ^ 

Phi/tolitharia) ^ 

Some idea of the value and importance of attending to 
the collection of these microscopical orQ:ani2;ed beingrs 



o 



e^ 



may be had by reference to Ehrenberg's Observations 



forming Appendix No. V, of Cc 




Sir JaTnt;o C 



Eoss's ^ Antarctic Voyage/ vol. i. p. 339 ; a bett^^^ idea 
by the perusal of Ehrenberg's numerous communications 
to scientific journals, some of which have been translated 
in Taylor's ^ Annals of Science ;' and the best idea by 
the study of Ehrenberg's great work, ' Entwickelung, 
Lebensdauer uud Struktur der Magenthiere und Badcr- 
thiere,' &c., foL, 1832. The important relatioi 



"1 1 r ^ *^ 



f tl 



lese 



minutest forms of animal life to great questions in geo- 



logy, to the alteration of coast-lines, and to the phenom.ona 



See also, on this subject, Lieut. Nelson's paper ' On the Geology of 
the Bermudas;' Geological Transactions, 2nd Series, toL y. pp. 103~- 

123. 






850 



ZOOLOGY- 



[Sect. XI. 



f 



i 



i 



of oceanic luminosity, make it indispensable to include 
them in directions for collecting facts in natural history. 

Whenever the surface of the sea presents a difference 
of colour and density, in the form of pellicles, streaks, or 
shining oil-like ^nots, lift up portions by dipping in thin 
plates of mica or stout paper, and raising them hori- 
zontally : dry these and preserve them in s. book, noting 
the latitude and longitude, the time of day, and the tem- 
perature of the sea. The animalcules remain attached 
to the pieces of paper or mica employed in their capture, 

and may be determined by subsequent microscopical 
observation. 

Where the sea seems pure and colourless a bucketful 
may be raised and strained through fine linen ; by re- 



peating this act a portion will commonly remain on the 



filter, which is then generally rich in invisible animalcules, 
and should be preserved in small glass bottles or tubes, 
with a bubble of air between the cork or stopper and the 
water, Anv visible o-olaf 



nous 



re 



moved and placed in spirit of wine, or the solution No. L 
Specim^ens of sea-water thus saturated with animalcules 
should bo prepared at each degree of latiiade and longi- 
tude traversed on the voyage, by which means the geo- 
graphical distribution of these minute organisms may be 
ascertained, when the species so collected are determined, 
after the voyage, by microscopic observation. 

bottles or tubes of the water of each mineral 
spring or hot-spring should be preserved for the same 

In a deposit from melted pancake ice from the 





Barrier, in 78^ 10^ S. lat.. 162' W. loner., brought home 



Anta 



'0-' 



o 



"/oyage, Ehrenberg detected of sili- 



( 












^i^ 



" I 



.'!• 



\. 



f 



Sect. XL] 



ZOOLOGY 






ceous- shelled Polygastria fifty-one species, including four 




new genera ; siliceous Phytolitharia twenty-four species ; 
and of calcareous-shelled Polythalamia four 
Small packets of the sand of each coast that may be 
visited, and of the sand or mud brought up with the 
anchor or the sounding-line, should be preserved; the 
localities, or latitude and longitude, being precisely noted 
in each case. 






1 . 



i J'- 



» 



ii£ 



u^^ 



r\ 



AcALEPHiE {Sea-Uulher or Medus(B^ Portuguese Men-of- 
loar, Jelly-fish, and other floating marine gelatinous 



J- 



animals). 

The brilliant but evanescent hues of many of this class 
of animals can only be preserved by coloured drawings 
executed at the time of capture. The solution No. I. 
will suffice for the preservation of the animals themselves, 
provided it be changed after they have reniained in it 
about twenty-four hours, for most of the gelatinous ani- 
mals, especially the medusae, contain a gi'cat quantity of 



fluid, which, mixing with the preserving liquid, dilutes it 



and renders it unfit for long-continued preservation. The 
best preserved specimens of these delicate animals are 
those that have been placed immediately after capture in 
the solution No. I. diluted with an additional pint of 
rain water, and which have been aftorwards transferred 
to fresh solution of the proper strength. Glass- stoppered 
bottles with wide mouths 



larger Acalephse. 



s are the best adapted for the 



#■_■- 



^- 



^:: 



r 




ZOOLOGYe 



[Sect. XT, 



i 



EcHiNODERMS (Star-Jish iAsterias% Sea-urchins [Echi- 
mdaf\, Trepang or Sea-cucumhers [Holothurice]). 

For the preseryation of the entire animal with the soft 

sea-urcliin (Echinus), the 
arsenical solution (No. II.) is preferable : the softer tre- 
pangs {HohthuricB) may be preserved in either solution. 
It should be gi-adually added to the vessel of water in 
which the living specimen is at rest, in order to kill it, 
with the soft appendages protruded or elongated. This 



is particularly requisite in the 



c 




of the Holothurice, 



which, if plunged suddenly in solution, are apt to squeeze 



out and rupture their viscera. W 



■h 



'o 



{Ophiurm) 






s called 



" brittle stars," from their habit of breaking themselves 

pieces when captured, these should be instantly 



mto 



plunged into a large 1 )asin of cold fresh water, when they 



die mas 



tate of expansion, and too quickly for the acts 
of contraction by which tlie rays are broken off. After 
lying for an hour or so in the fresh water they may be 
transferred to the solution : if preserved dry they should 
be dipped for a moment in boiling water, then dried in 
the sun or in a current of air, and packed in ,.aper. 
■^Fhen the specimens have soaked in solution one or two 
days, according to the temperature, they should l)e re- 
moved into t>esh solution. The Echini should be sewed 
up each in a separate bag of muslin, and not be crowded 

F 

so as to press upon each other in the same bottle. The 
starfish and sea-urchins that are preserved dry should be 
emptied of their viscera or soft contents by the mouth or 
larger (lower) aperture, and should then be soaked in fresh 



f 



1. 




^ 



( 



f 



■^ 



'A^ 



'- 1 



W" 



Sect XL] 



ZOOLOGY. 



35^ 



o 



water, clianged two or three times, for so many hours, or 
until the saline particles of their native element have been 
extracted, before they are dried. The Echini should be 
wrapped up in cotton and sewed up, each in its separate 
bag, in order to preserve the spines, which may become 
detached in the course of a voyage, and are apt to 
become so if the precaution of soaking away the saline 

' taken. AH Echini nnd star- 
fish should be examined for small shells (Stylifer of 
Broderip, for example), which nestle in and among the 
rays and at the roots of the spines, and for otlier parasites. 
Recent Pentacrini (Lily-stars), especially their bases, 
will be valuable acquisitions. They m.ay be dredged up 
of large size in tropical seas, as those of 



X 



ousl 



G 



ipl 



> 



Entozoa (intestinal worms and other internal parasites) 

These arc to be preserved either in solution No. I. 
or in colourless proof-spirit. This class of animals has 
been too much neglected by collectors. Every animal 
that is opened and dissected, especially fishes, may pre- 
sent rare or undescribed species of Entozoa. The eyes 
of fishes are often the seat of such : the noses of sharks 
are frequently infested by them. They may be found not 
only in the alimentary canal, but in the tissues of most of 
the organs. When the parasite is adherent, the part to 
which it adheres 



should be removed 



vith it. care bein 





to secure the whole mouth or proboscis of the 
parasite. When it is encysted in an organ, the cyst is 
to be removed entire with the snrrounding tissue of the 
organ. Portions of muscle or other tissue which app^'^r 



■ 






r 



354 



ZOOLOGY. 



[Sect. XI. 






speckled with minute white spots should be preserved as 
these may be occasioned by the cysts of Trichince or 
allied microscopic Entozoa. The number attached to 
the specimen should correspond with that in the list 
having reference to the animal and part or organ infested 
by the parasite. 

Epizoa {Lernea or Fish-lice, and other external para- 
sites) ; Annelides (Leeches, Worms, Nereids, or Sea- 
cerdijpedes, Tube- worms , ^^c). 

Tliu exterior surface, the mouth, and the gills of all 
fishes should be exaramed for parasitic animals, some of 
which exhibit the most extraordinary forms and combi- 
nations of structure, as, e.g., the Diplozoon of Nordmann, 
a e:enus of Entozoa, from the gills of the bream. When 




tiie parasites adhere firmly to the part they should be cut 
out with the adhering organ entire, which sometimes 
penetrates to a great depth in the flesh. The exterior 
surface of porpoises, grampuses, and the larger species of 
the whale tribe should be scrutinized for adherent para- 
sitic animals. Rare kinds of leeches may be found on 
fishes, as, for example, the BraacheUion of the Torpedo. 
A species of leech ..Ith external tufted gills, Hirudo 
Iranchiata, has been detected on a marine tortoise or 
turtle in the Pacific, the anatomical examination of which 
is especially recommended by Cuvicr. Leeches and all 
the various kinds of sea-worms comprehended under the 
class name " Annelides," and including the Nereid 
sea-centipedes, usually found amongst sea-weed or under 
stones, sometimes attaining the length of twelve feet ;* 

* See the specimen, from Bermuda, of Leodice gigantea. No. 253 a, 
Museum, College of Surgeons, London. 



'? 



\ 



I 



^^ 



Sect XI.] 



ZOOLOGY. 



355 



usu 



in 



i 



v 



It* 



7 



J- 



], ' 



loured tentacles, may be preserved in the solution iNo. I. 

spirit. Those, however, as the Sei-puUdo^, 



¥ 
*. 



colourles 



that form calcareous tubes, should be preserved in the 
solution No. II. In all cases it is desirable that the 



specimens should be allowed to die gradually in the 
water they inhabit, when they commonly display their 
natural external form and appendages in a relaxed state ; 
they should then be immediately put into the solution or 
spirit to prevent putrefaction, which otherwise takes place 
rapidly. 

CiRRiFEDiA (Barnacles and Acorn-sheUs or Crown-shells). 

The Barnacles or pedunculated Cirripeds, with soft 
stalks, should be preserv^ed in the solution No. II. or in 



spirit; they are commonly attached to floating timber 



and the smaller species to seaweed, shells, &c. The 



sessile kinds (acorn-shells, &c.), which encrust tne coast- 
rocks all over the world, and are found parasitic on 



turtles, whales, &c., should likewise be preserved in spirit 
or solution No. II., as the included animal is necessary in 
some genera for the 



recognition 



of the sDecies. 




colours of the pedunculated kinds should be noted whilst 
fresh. If the sessile kinds are preserved dry the included 
animal ought never to be taken out. In removing all the 
kinds from their points of attachment care must be taken 
that in some specimens, at least, the base, which is either 
membranous or calcareous, be preserved. It is particu- 
larly desirable that some young as well as large specimens 
should be collected. In the tropical seas certain corals 
and shells contain embedded in them singular forms of 



t 



oob 



ZOOLOGY. 



[Sect. XI. 



cirrjpeds, which, presenting externally little more than a 
simple aperture, are easily overlooked ; such kinds had 
better be preserved in the coral. Others live embedded 
in sponges ; two genera live on whales' skin [Coronula 
and Tuhidnelld), the development of which needs to be 
studied by specimens of the ova and young ; another less 



skin of turtles : a third 







itself to the manatee 



or sea-cow; and some small and interesting species of 
barnacle are parasitic on sea-snakes. Lobsters, crabs, 
bivalve and other shells, as well as floating pieces of 
wood, or even net- corks, become the habitat of animals of 
the class Cirripedia. It should always be noted to what 
animals these parasitic cirripedes are attached, as well as 



any circumstances that may determine the period durin^T 
which they have remained attached. 



ers 



i 



m 



^>j 



Crustacea {Shrimps, Sea-mantises, Cray-fish, Lohst 

Crabs, and King-crahs). 

All the animals of this class are most profitably pre- 
erved in spirit or solution. If they be defended by a 
soft, flexible, or horny covering, the solution No. I. 
answers well ; if by hard, calcareous plates, the solution 
JS o. II. is preferable. They vary in size from microscopic 
minuteness to upwards of a yard in length. The larger 
and middle sized specimens should be kept by themselves, 
"" """' " " bag if placed with others in the ^-^mQ 



or sewea up m a 
jar or bottle. iUre and beautiful kinds, with transparent 
glass-like shells, may be captured by the towing-net in 
tropical seas. The minuter kinds have been commonly 



neglected, especially those of fresh water : any such 



\ 



i 

I 



I 



I 



! 






L i 



r 



\ 



St^ct XL] 



200L0GY. 



' = 

O 



7 



species observed darting about in the fresb water of foreign 
countries should be preserved in tubes, in spirit or solution 
No. I. The larger kinds of marine Crustacea should be 
suffered to die in fresh water before immersion in the 
preserving liquor. The different kinds of kina-crab 



{Limuhis) usually found on sandy or muddy coasts are 
particidarly worthy of preservation in spirits or solution 
with the ova or young. 

In preparing Crustacea for drying care is to be taken 
to preserve all their external parts as perfect and as ex- 
pressive of the natural progressive action as possible. 
Crabs and lobsters should be cleaned out as soon as 
practicable, i. e.^ the soft internal parts and the flesh 
should be removed, and they should be soaked in fresh 
water previous to drying. The claws when large require 
to be separated at each joint for the purposej and then 
refixed, or a small piece may be neatly removed and 
afterwards replaced- When dried, the specimens should 
be wrapped in very soft paper and then packed in cotton, 
so as not to allow of their being displaced in the case nor 
to touch one another. It is desirable, wdth regard to 



brilliantly- coloured crabs, to w^ash them over, alter they 
are dried, with a thin coat of the following varnish : 

Varnish for Crabs, Eggs. &c. No. I. 



Common gum 
Gum tragacanth . 



4 02. 

Joz. 



Dissolve these in three pints of waterj add to the solution 20 grains of 
corr- Ive sublimate, and 20 drops of oil of thyme, dissolved in 4 oz. of 
spirit of wine ; mix it well, and let it stand for a few days to sei;arate: 
the clearer part is to be used as varnish ; the thicker part forms an 
excellent cement. 

A very important subject of investigation is the develop- 
ment of the Crustacea from the earliest period at which they 



358 



ZOOLOGY. 



[Sect. XL 



Sec- 



can be observed to the assumption of the mature or parent 
form. The eggs, usually of some bright colour, attached 
beneath the tail of the female crab, lobster, or shrimp 
should be examined for this purpose : the embryo if in 
course of development may be readily seen by opening 
the egg under a moderately magnifying power (see the 



note on Microscopes). Drawings of the different forms 
or stages of the embryo should be made, if possible, and 
the egg's nnd embryos preserved in spirit or solution in 
small glass tubes. 



-1 



Insecta. 

Some specimens of all kinds of insects should be pre- 
served for anatomical examination in spirit or the suhition 
No. I. Many of the softer kinds of insects and spiders 
can only be profitably so preserved. Care must be taken 
that the softer kinds of insects are not put into the same 
bottle with the harder kinds. Gauze nets must be used 
for catching the Lepidoptera (butterflies and moths) on 
the wing, and a fine muslin net, like a landing-net, for 
the water insects. Many species may be taken by 
preading a cloak, or placing an open umbrella reversed 



under trees or bushes, and shaking or beating the latter. 

Caterpillars should be carefully placed in a perforated 

box with the leaves of the plants on which they are found 

feeding : they will often undergo their metamorphosis in 

this captivity, and no lepidoptera are more ncrfect than 
th 



so thus hred, as it is termed, if carefully watched. 
The perfect insect should be accompanied, if possible, by 
its larva (caterpillar) and jmpa (cl 



rysalis or cocoon), 
together with a specimen of the plant on which it is found 
feeding. The latter should be kept in an herbarium set 



, 



( 



\ 



ap« 
spf 
be 

of 

ani 

the 
an' 

lai 

rei 

ars 
ar( 
inc 
th( 
plf 
bu 
th( 
on 

St£ 



sa 



gr 

en 

T] 

of 
ad 



ui 



ai 



ca 
or 




fs 



is 

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f ' 



II 



,A \ 



(-' 



Sect. XI.] 



ZOOLOGY. 



359 



apart for the purpose, and should have a number corre- 
sponding with that of the insect. Larvn; and pupa; may 
be preserved in spirit or solution, as well as a specimen 
of every perfect insect that can be spared, with a view to 
anatomical investigation.- It must be remembered that 
the larvcB will very soon lose their colours when so treated, 
and, in order to retain these, a specimen or two of the 
larger ones and of their pupa? may be opened, the viscera 
removed, and the inside, "fter it has been brushed with 
arsenlate soap, stuffed with cotton. Boxes lined with cork 
are the best conveyances for dried butterflies, moths, and 
indeed for insects in general : or they may be pinned in 
the crown of the hat until they can be transferred to a 
place of safety. The more delicate insects, such as 
butterflies, moths, sphinxes, the different species of mantis, 
the locusts, dragonflies, &c., after being killed by pressure 
on the thorax, should be pinned down, while in a relaxed 
state, with the wings and legs kept close to the body, to 
save space and prevent collision. The pin should be 
greased or oiled to prevent rust, and if pointed at both 
ends the specimen more readily admits of being turned. 
The pin should be made fast so as to allow of the motion 
of the box in all directions, and the fastening must be 
adjusted to the weight of the insect. The harder winged 
insects may be killed by immersion in hot water, and 
after having been dried on blotting-paper, may be laid 
carefully in boxes upon cotton, so as not to interfere with 
or injure each other. A ready mode of preserving beetles 



'f. 






r- 



> - 



(Coleopterd) 



( 



on any foreign coast. 



is to put them, when dried, in a box, on tlie bottom of 



which a layer of fine dry sand has been strewed. 



\\Tien 





^^^ 



360 



ZOOLOGY. 



[Sect XI. 



the layor is overspread with beetles they must be covered 
with another layer of sand, and the packer must proceed 
with layers of beetles and sand alternately, till the box 
which should be water-tight, is quite fulL when it should 
be screwed dow^n and pitched at the seams. Mr. Dc 



u'wm 



preserved all his dry specimens of insects, excepting the 
lepidoptera, between layers of rag in pill-boxes, placing 
at the bottom a bit of camphor, and they arrived in an 

F 

excellent state* 



B 



I 



MoLLUSCA (Catties, Squids, Snails {land and sea), Slvgs 
{land and sea), Shell-Jish, Cowries, Limpets, and 
Bivalves, as Mussels, Oysters, Sfc), 

" A superficial towing-net, another so constructed as to 
be kept a fathom or two below the surface, and the deep- 
sea trawl, are the principal agents for capturing these 
animals. But when the tide is at the lowest, the collector 
should wade among the rocks and pools near the shore, 
and bcarch under overhanging ledges of rock as far as his 
arms can reach. An iron rake, with long close-set teeth, 
will be a useful implement on such occasions. He should 



grow 



a 



care to protect his hands with gloves, and his feet with 
shoes arui stockings, against the sharp spines of echini, the 

weevers (sting-fishes), and the stings of 
medusa (sea- nettles). In detaching chitons anApateUcB 
(limpets), which are all to be sought for on rocky coasts, 



back 




uf 



u 



the surgeon's spatula* will prove a valuable assistant 



* A case knifej in experienced hands, is even a better instrument ; but 



great cure must be taken not to wound the ngamentous border of the 
sheU ot the chiioiis, and not to injure the edges of the limpets. 



d 



pi 



^ -- ■ 



i 



JX 

^ 



r 



f 



t 



:| 



V 



r 




1 1 



v.- 



'^i 



4 



J tJ ^ 






Sect. XI.] 



ZOOLOGY. 



361 



Those who have paid particular attention to preserving 
chitons have found it necessary to suffer them to die 
under pressure between two boards. Ilaliotides (sea-ears) 
may be removed from the rocks to which they -ndhere by 
throwing a little warm water over them, and then giving 
them a sharp push with the foot sidewa} s, when mere 
violence would be of no avail without injuring the shell. 
Rolled madrepores and loose fragments of rock should be 



turned over 







other testacca are 




frequently harboured under them. Numbe 






conchifera^ and radiata are generally to be found about 
coral reefs." — Broderip. 

cVmonnj the floating moUusca likelv to be met with in 
the tropical latitudes is the spirula^ a small cephalopod 



with a chambered shell. An entire specimen of this rare 
mollusk is a great desideratum ; and if it 



should 



be 

captured alive, its movements should be watched in a 
vessel of sea water, with reference more especially to the 
power of rising and sinking at will, and the position of 
the shell during those actions. The chambered part of 
the shell should be opened under water, in order to 
determine if it contain a n;as; the nature of this <;as 



^ 



should likewise, if possible, be ascertained. As a part 
of the shell of the spirula projects externally at the pos- 
terior part of the animal, this part should be laid open 
in the living spirula, in order to ascertain how far such 

mutilation would affect its power of rising or sinking in 
the water. 

In tl- event of a living pearly nautilus {Nautilus Pom- 
pilius) being captured, the same observations and experi- 
ments should be made on that species, in which they 

E 



862 



ZOOLOGY. 



[Sect, XI. 



»»ould be attended with more precision and facility, as 
the species is much larger than the spirula^ and its shell 



external 



The towing-net should be kept overboard at all prac- 
ible periods, and drawn up and examined at stated 
hitervals. a,s some of the rarest marine animals have been 






taken by thus sweeping the surface of the sea, 

A sketch or drawing of molluscoas and radiate animals, 
of which the form and colour are liable to be matcriallv 

mi 

altered by death, or when put in spirit, will aid materially 
in rendering the description of the species useful and in- 
telligible. 

Some of each species should be preserved in spirit or 
the solution No. II. If they have died with their soft 
parts protruded, they should be suspended so as to 
prevent distortion from pressure. If the shell be of the 
spiral form 5 the whorls should be perforated with a fine 
awl so as to allow the spirit or solution to enter ; other- 
whole 



up tlie 



4 



wise, as the maiil body of the animal fills 
mouth of the shell, the deeper seated and softer parts 
would become putrid before the preserving liquor could 
get to them. 

Where the animal has been detached from its shell, 
the soft parts and the shell should be marked with corre- 
sponding rmmbers. When the animal is furnished with 
an operculum (the little door which closes the mouth of 
many turbinated shells), it should be carefully preserved ; 
and if detached from the animal should be so numbered 
as to prevent the possibility of its being attributed to the 

never be cleaned, but 



wronff snecies 



sp 



Shell 



s should 



should be preserved as they come from the sea, taking 



Sect. XL] 



ZOOLOGY 



3 




< 



^^ 



t ^ 



li 



1 



.-"^' 



^ 



> 



-^ 



W 




care only to fill the mouths of those which are turbinated 
with tow or cotton to prevent fracture. It may he some- 
times requisite to put a live shell into hot water and boil 
it a minute or two, in order to dislodge the animal^ wl 
may then he removed with a crooked pin. 

The land-shells are found in various situations ; as in 
humid spots covered by herbage, rank grass, &c. ; beneath 
the bark or within the hollows of old trees, crevices of 
rocks, wails, bones, &c- ; about the drainage of houses, 
or in the dry season by digging near the roots of trees. 



Early in the morning, especially in rainy weather, is the 
best time for taking them. The freshwater kinds may be 
sought for in quiet inlets, on the sides of lakes, rivers, and 
brooks : the greater number of univalves occur at or near 
the surface, under the leaves of aquatic plants and among 
decayed vegetables ; while the bi.^lves and certain uni- 
valves keep at the bottom, and are often more or less 
imbedded in the sand or mud, froiii wliich they may be 
raked into a landing-net. 

With regard to the marine bivalves, rocks, subma- 



rine clay-banks, 
should be carefu 



piles, 



stones, and indurated sand, 
jcted for Pho lades. Lithodomu 



and other boring species. If the collector should find 
any of these perff»rators in the ruins of an ancient temple, 
or in the remains of any ancient works of art, 
adhering shells {serpuke for instance) attached to the 
surface of such works, the specimens become doubly 
interesting, especially in a geological point of view. In 



or anv 



such cases, the situation should be acciiratelv noted, as 
well as the distance of the perforations from the surface 
of the sea, either above or below. 

By digging with a wide-pronged fork in sand-banks, at 

R 2 







364 



ZGOLOGy. 



[SfctXL 



low water, many bivalves, such as 5c>/eri.9, Cardia^ Te1lin(B, 
&c., will be procured alive ; andj if the inhabitants of the 
coast be accustomed to diving, their services should be 
secured for deeper water. Care must be taken not to 
separate the ligament which binds the hinge. When the 
animal is dead the shell will gape, and the soft parts 
may then be removed without injury. Attempts to open 
bivalves, while the animals are alive, generally terminate 
in great injury to the shells. 



the dredge is indispensable. 



For deep-sea shell 
Dredging requires experience to judge of the length of 
rope to be used ; if there be too much on a sandy bottom, 
the dredge will bury itself; if too little, it will not scrape 
properly : on rocky boitonis the rope must be kept as short 
as possible ; in deep water the dredge can only be made 

r 

to act effectually by placing a weight on the line, which. 
as a rule, may be about one-third of the weight of the 
dredge, and placed on the line at about two-thirds of the 
depth of the water ; the object is to sink the rope, and 
covmteract the tendency it has to float the dredge. The 
contents 



01 



the dredge are best examined by means 
of sieves, of which three should be used, one over the 
other, first a riddle, next a wheat sieve, and third an oat 
sieve ; these may be fastened together, the contents of 
the dredge being emptied into the riddle, and water being 
poured upon them, the mud, &c. will be washed off, and 
the contents separated, so as to be very easily examined ; 
by this plan 



a 



I 



hundred fold more will be discovered^ than 
can be found by searching in mud or sand in the usual 
manner. Besides shells, numbers of crabs, star-fishes, 
sea urchins^ worms, corals, zoophytes, alga?, &c. are 
procured by the dredge. 



i 






^^ 



Sect. XI,] 



ZOOLOGl' 



365 



i 



*\ 



■ ft 



4M 



1 



*•'■ 



\ 



* 1 



*^ 



^ ^ 



VERTEBEATA 



Fishes. 



9 



All specimeiii5 not too large to be preserved entire should 
be immediately plunged into spirit or solution. In the 
case of cartilaginous or soft-spined fishes the solution should 
be No. I. Fishes with hard spines should be preserved in 
the solution No. IL It will be found to be convenient to 
have a common receptacle for the fresh-caught specimens 
and to transfer them, after soaking a day or two, into the 
vessel, with fresh spirit or solution^ in w^hich they are to 
be sent home. As the colours are more or less eva- 
nescent, it is desirable that they should be accurately noted 

before death. 

With regard to large specimens of the shark or ray 
kind, John Hunter recommended that ^^ the :??bdomen 
should be first opened, then the head taken ofi* by dividing 
the fish below the heart across the upper part of the liver, 
by which means the mouths of th^ oviduct; 



^^ ^^ be a 



'^j IT 11 



female, the heart, and head are all preserved together. 

" The tail, if a thick one, as that of a shark^ may be 
taken off* a little below the anus, and the trunk alone 
preserved for examination. If the trunk be too large, it 
should be cut through above the pelvis, and the parts 
contained in the hinder portion, as the claspers of the 
male, should be preserved in spirit. 

" If a female, separate the two oviducts througli their 
whole length, where they run along the abdomen, on each 
side of the spine ; but keep them attached to tlie cloaca 
and surrounding parts, and preserve the whole. 



tti- 






->^ 



^*t 



366 



ZOOLOGY. 



[Sect, XL 



" If with young, or eggs, take the whole out in the 
same wav, without opening the oviducts. 

'' The peculiaritiep of the foetus in these animals should 



b 



e a 



ttended to. 



^^ If noi of the ray or shark kindj take out 6uch parts 
from the abdomen as are uncommon or singular. 

" If tish of the roe kind (u e. osseous and cyclostomous 
fishes), then cut transversely through the fiah near the 



lower nart of th 



a 



^me 



Thi 



c 



avcs part of the roe, with the connection between it and 



oncemed 



" The tail may be cut off some Inches below tiie anus. 

" The stomach a--^ intestines may be saved, if any- 
thinfy oarticular is observed in them. They should be 
examined for the presence of entozoa, which, if adherent 
to tlie coats of the intestine, should be preserved with the 
part to which they are attached. 



ff 



** Eyes oi- fishes are proper objects of preservation 

'' S^^parate and preserve the heads of such fishes as 

have anvthing singular about the teetli or gillSj and are 



too large to be preserved entire 



>? 



£ 



Preserve the jaws and teeth, toetether with the back- 



C5 



bone, or some of the vertebra, of every shark or large ray 
which is not otherwise preserved^ behig careful to keep 
the teetli and vertebrse of each individual attached toge- 
ther. Such specimens would be of great service in the 
determination of fossil teeth and vert^bree. A section of 

part of the vertebral column 



the iaws and teeth with 

should be preserved in spirits or the solution No= II 



Amongst the more interesting fishes of the Southern 



Ocean is the Fort Jackson shark {Cestracion PhilUppiy 



\ 



Sect. XI.l 



ZOOLOGY. 







I 



I 



''.I 



. ff 






'■J 



1 



Tl 



* nfU 



w 



Moderate-sized specimens of tins species should be pre- 
served entire ; and the head, vertebraj, with the dorsal 
spines, Tiscera, and especially the impreg-u-^3d oviduct, 
should be placed in spirit or solution. The Southern 
Chimara ( Catlorhyndnts 
especial attention of the naturalist. 



UUlCI 



tis) merits also 

/ 



c 



O 



Gambia, and of South 



America, contain a peculiar eeWike fish, tlie Lepidosiren 

_ x 



with filaments for fins 



5 



burrow 



in the mud during the dry season. The male and female 
of this fish, and the ova and young in different grades 
of development, preserved in spirits or the solution 
No. I., are much wanted, in order to complete its ana- 
tomical and physiological history. 

With regard to most fishes preserved in spirit or sol 
tion it is desirable to inject some of the preserving liquor 
into the alimentary canal, and, if the fish be large, to 



make a small opening into the Ijeliy. The more delicate 



u 



specimens should be sewed or wrapped in rmen, m order 

to preserve the scales. 

For dry specimens the larger kinds ma; ')e skinned, 
and the skin should be washed on the inner side with the 
arsenical soap, and then loosely filled with cotton, wool, 



or tow. With regard to the smaller or moderate-sized 
specimens, the Curator of the Dublin University Museum 
states : — " An excellent mode of preserving fishes, easily 



accomplished, may be thus described : Lay the fish on a 
table, with the side up which you wish to preserve, then 
with scissors cut it, so as to separate the fins, skin of one 
side, mouth, and tail, from the body and viscera ; spread 
the skin so obt^imed on a linen cloth, fold it over it, and 



368 



ZOOLOGY. 



[Sect. XT. 



subject It to -ome small pressure ; remove the cloth, and 
ake away any portions of flesh which may appear easily 



f 



removeahic ; then fold it in a dry cloth and subject it 



again to pressure 



ct 



board and a few weights or stones 



will do if no other press be at hand ; repeat the operation 
at intervals, until the skin becomes quite dry^ then wash 



it well at both sides with the varnish No. L When dry, 
sew it on strong paper, and you will have as it were a 



coloured drawing of your fish. The great advantages of 



this phin are the ease with which it is done, and the small 
space specimens occupy when finished ; a large collection 
does not require more room than so many dried plants/^ 



Reptiles {Crocodiles, Tortoises, and Turtles, Liza,Js, 
Snakes^ Toads. Frogs^ Salamanders^ and Newts). 

All these animals are best preserved, particularly the 
smaller kinds^ in spirit or solution No. II.. Both pre- 
serving liquors require to be changed once at least, if not 
tvv^ice ; a piece of linen being wrapped round each f^peci- 



men preserves the scales ; this is requisite at least for the 
smaller li^a. ^" and snakes. In skinning lizards the ope- 



rator must be very ca^reful not to break the tail. The 
larger snakes may require to be skinned, when care should 
be taken to preserve the head attached to the skin, and 
the skins with the h.ids attached should be put into 
spirits. In flaying serpents great care must be taken not 



to damage the scales : and the operator should be cautious, 
for his own ^ake, w^hen employed about the head of the 
poisonous species : a scratch from a fang of a rattle- 
snake or of a cobra di capello soon after death may 
DC fatal. The heads of both poisonous and innocuous 



i 



t 



. 



^ 



Sect. XI. 1 



ZOOLOGY 






4 I 



i 






t** 



■;t 



i 



species should be preserved for the examination of their 



teeth. 



Tortoises and turtles may be prepared in a dry state, 
the breastplate being separated by a knife or saw from 



t 



he back, and, when the viscera and fleshy parts have been 
removed, restored to its position. The skin of the head 
and neck must be turned inside out as far as the head, 
and the vertebrae and flesh of th.e neck should be detached 
from the head, which, after being freed from the flesh, 
the brain, and the tongue, may be preserved with the skin 

of the neck. 

must be turned inside out, and the flesh having been re 

moved from the bones, they are to be returned to their 



In skinning the legs and the tail, the skin 



places by re-drawing the skin over them, first winding a 
little cotton or tow round the bones to prevent the sl:in 
adhering to them when it dries. 



When turtles, tortoises, crocodiles, or alligators, are too 



5 



large to be preserved whole in liquor, some part 



as the 



head, the whole viscera stripped down from the neck to 
the vent, and the cloaca, should be put into spirit or solu- 
tion. The bones of such specimens are especially desi- 
rable : they may be separated and scraped clean : all 
those of the same individual should be packed in a bag 



or box with bran, paner-cuttings, hay or < 



iried seaweed. 



fc' 



The bones of the smaller species need not be sepa^:^^•^^ 
After detaching as much of the flesh as is practicable, the 
entire skeleton maybe suffered to dry in a naturally con- 
nected state, and then may be laid in a box on cotton, 
tow, or other suit material, and covered with the saixxO. 



rit 



The eggs, at different stages of development, of croco 



diles 






turtles, and tortoises, and also of the larger snakes, 

R 3 



oiO 



ZOOLOGY, 



[Sect. XI. 



should be preserved in spirit or solutioiij as also the 

of most reptiles are 



As the 



olours 



young animals, 
much altered by spirit, a coloured sketch should he 
made, v/hen practicable, of them either during life or 
immediately after death. 

Tiie batrachia or amphibia should be obtained in the 
different stages of their metamorphoses. The different 
species of the burrowing snake-like genus called CwciUa 
are especially desirable in the young state. The gravid 



oviducts of these and of the viviparous kinds of sala- 
mandci should be preserved in spirits or the solution 
No. I., together with the young of the perennibranchiat? 



a 

Vv 



amphibia of the United States, c^Jled menopom.a, am- 
phiuma, menobranchus, siren. 



Birds. 



A 1 



2 

O 



vll the rarer kinds, especially the smaller specie 
should be preserved in spirits or the solution No. IL for 
anatomical examination. Of such as are too large to be 
preserved entire, the gullet, stcTOach, or gizzard, liver, 

the male organs, should all 



iiitestines, ovary 



oviduct, or 

4-1 



be taken out as lev/ as the anus, and with the cloaca 
should be preserved in spirit or the solution No. I, The 
tongue and trachea with the lower larynx should be pre- 
served wet by themselves ; and if more than two specimens 
of a ror3 bird are captnred, the head of one should be 



presox^ved in strong spirit 



portion 



being removed to allow the spirit to get to the brain. 



The most common as well as convanient mode of pre- 
erving birds for zoological purposes is by removing and , 



preparing the dry skin, with the head and feet attached, 



i 



^ 



Sect. XL] 



ZOOLOGY. 



371 



V..., 



tl^ 



i^^ 



h. 



• * 



I 



Y 



■•'^ 



^^ i 



f 



! 



r^l 



and a few words on the mode of performing this operation 
may be found of use. First put some cotton or bits of 
blotting-paper into the mouth of the bird to abborb the 
blood that may be there, and then tie the bill close by 
passmg a thread with a needle through the nostril and 



round the lower mandible ; then, after parting the breas 



feathers, the incision for skinning should be made from 
the lower point of the sternvmi, or brea.;^t.-bone5 to the tail, 
care being taken not to cut into the body. Whilst 
removing the skin, thrust cotton-wool between it and the 
body, at the parts not being operated upon, to keep the 
feathers clean, and prevent them from coming in contact 
with the moist parts. Having detached the skin of tLosc 
parts on each side, the legs are next to be, pushed through 
and cut off at the joint that protrudes ; and then follows 
the more difficult process of separating the vertebra near 
the tail. Having detached, however, the legs, and leaving 
the flesh upon them for the present, the operator must 
continue to separate the skin from the hind part of the 
body as well as he can, and then very carefully cut 
through the vertebral column near the tail, without in- 
juring the skin above it ; that of the back is then detache .1 
with much ease, and a little practice Is now necessary to 
keep back the feathers of the breast while the skin h 
drawn over the shoulders ; the wings should then be ^epa 



s 



. J 



rated at the shoulder joint, and the skin pulled over tlie 
neck, and very gently and carefully o , ^r the head, taking 
especial caution not to enlarpre the auditory orifices or 
those of the eyes. With the majority of birds the skin 
may be drawn back over and from the head without much 
difficulty ; but there are some, as woodpeckers and ducks, 



1 



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i 



i 

1 



I 

i 

! 

i 



5 



i 



372 



ZOOLOGY. 



[Sect, XL 



in which the head is larger than the neck, and conse- 
quently could not be drawn through that part without 
stretching the skin : it is advisable to make an incision in 
tlie skin at one side of the head, and thus uncover the 
skull to remove the fleshy partSj not forgetting the tongue, 
eyesj and brain. In small birds a quill cut in a slanting 
manner will be found useful to scoop out the brain ; a 
little wool may afterwards be wound round it to remove 
any moisture that may remain in the hollow parts of the 
skull, ^^/bilst skinning the head, upon reaching the eye 
it will be necessary to cut the tough membrane that sur- 
rounds that part. The brain and flesh being thoroughly 
removed, and the skin anointed with the arsenical soap,* 
the limbs are easilv drawn back, a little cotton or tow 
being previously wrapped round the thigh-bones, and 



* 



Receipt for Arnenical Soap, 



Camphor . 
Arsenic in po'wder 
White soap . 
Salts of tartar 
Lime in powder * 



5 ounces, 
2 pounds. 
2 pounds. 
12 ounces. 
4 ounces. 



Cut the soap in thin small slices^ as tliln as possible, pat thetn in a pot 
over a gentle fire, with Tery little "water, taking care to stir it often with 
a wooc-... poon: when it is well melted, put in the salts of tartar and 
pow{lered chalk. Take it off the fire, add the arsenic, and triturate the 
whole e-'^tly. Lastly, put in the camphor; which must first be reduced 
to powder in a mortar by the help of a little spirits of wine; mix the 
whole well together. This paste ougbt then to have the consistence of 
flour paste. Put it into china or glazed earthen pots, taking care to put 
a ticket on each. 

When it is to be used^ put the necessary quantity into a preserve-pot, 
dilute it with a little cold water until it ha=: tliC consistence of cream ; 
cover this pot with a lid of pasteboard, in the middle of which bore a 
hole for the handle of the br 



-,X- 



J. 



The three first 5x.;zredients in the above receipt may be used, if the 
whole cannot be readily obtained. 




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Sect. XI.] 



ZOOLOGY. 



373 



care being taken that no feathers adhere to the interior of 
the skin of them and are drawn in with it, and then (after 
putting some cotton into the cavities of the orbits) the 
head must be pulled forth by means of the bill, an opera- 
tion requiring much caution, so as not to tear the very 
tender skin of the sides of the neck ; this is frequeiitly a 
rather difficult matter with beginners, and may be much 
facilitated by partially crushing the skull^ which is easily 
put back into shape when the skin is again over it ; bits 
of cotton should also be freely used to prevent the feathers 
being anywhere soiled by adhering to the skinned body. 



as they are extremely apt to do, despite all carCj unl 







now re- 



some such precaution be resorted to* Havir 
turned the skull wathin the skin, a little art is necessary 
in arranging the feathers of the head properly, wi 
best done with a larjre needle: the evelids should he 
neatly placed, and not stretched too large, the feather 




IS 






covering the ears disposed as they originally were, and 
the orifice of the ears contracted to its proper form ; the 
feathers before and over the eve should also be set 



«J 



nd occiput 



naturally ; and lastly, the skin of the crown t 
should be loosened or lifted from the skull, and not be 
pulled too tightly backward. The arsenical soap is to be 

skin, and the legs 



sparingly applied to the inside of the 
and beak brushed with a solution of corrosive sublimate. 
As regards the rest, it is as well to tie together, but not 
too closely, the bones of the two wings, to put a little 
cotton around these and the bones of the legs, and, in 



stuifing the bird, to avoid stretching the skin by putting 



in too much cotton, especially to avoid puffing out in 
neck, in which it is enough to prevent the skin of its tw. 






-i->'r-r_i-^ 



374 



^w 



ZOOLOGY, 



[Sect XL 



ides adhering together, and lastly, to mind that the bird 
is restored to its original length and proportions, and that 
the feathers are laid down as smooth as possible. In 
large birds, more especially, it will be found useful to put 
a reed or thin bit of stick up the neck, around which the 
stuffing of the neck may be wound, for this will prevent 
the tender skin of the neck bursting, when dry, upon the 
spcciineii not being handled with sufficient care : and in 
larsre birdsj it is also necessary to make an incision above 



the elbow-joint of the vfings extending along their under 



surface, and to remove from thence the muscles of that 

In general, it will be found more easy to skin 



part 

birds, after one or two trials, to the complete satisfaction 
of the operator, than to put thein nicely into shape afcer- 
wards, in the form they are to take on drying : and upon 
being dried thoroughly, they are to be rolled up in paper 



and tied round with a string. 

Birds should be skinned as soon as they are cold ; they 
c^^anot be kept so long as quadrupeds, and as soon as 
decomposition begins the feathers are affected, and, if the 
operation of skinning be deferred till it take place, they 
will drop off. The os coccygis, or riimp-bone, should be 
left with the skin, otherwise the tail-feathers will be liable 
to fall out. 

should be procured if pos- 



The nest. 



eQ'gs» and 



young snouio o( 



SI 



:i.i 



! 5 



SlIJL 



To preserve the eggs of birds with their nests, each 
nest should be put into a round box just large enough 
to contain it. After having made a small perforation 



at each end of the eggs, and expelled their contents, 
some cotton should be laid upon them to keep them 



\ 



( 






# 



I 

I 



Sect. XL] 



ZOOLOGY. 




75 




I 



Y.i 



1 ' 

i ■ 



from being moved aboutj and the whole coyered vdth 
the lid. 

Large eggs, as those of the ostrich and casbowarv^ 
at different periods of incubation, should be preserved in 



* • 



spirit. 

To each bird attach a note — 1. The colour of the eves, 
bill, and legs, before they fade, 2, The season of the 
year when killed, and in what locality, 
state whether male or female. 



3* If known 



The skeletons of birds may be prepared in a short time 
for sending home by removing the viscera, cutting awav 



all the soft parts, breaking down the brain with a probe 
or stick and washing it out by the " foramen magauraV or 



hole for the exit of the spinal marrow, and drying the 
skeleton with its parts naturally connected, except the 
head, which may be packed in the thorax ; and the whole, 
when dry, packed in bran or sawdust. Admit the bones 
of only one individual into each bag or box, taking care 
to label it with the ?ame number as that attached to the 

The viscera and any other soft part which appears 
curious should be preserved in spirit or the solution No, T 



skin. 



s 



Mammals {Hairy Quadrupeds, Seals, Porpoises, 

Grampuses, Whales). 

The smaller kinds, as bats, shrews- mice, may be pre- 
erved entire, in spirit or the solution No, 11., an opening 



being 



made in the skin of the belly to give the preservin_ 
liquor access to the viscera, and care being taken not to 




crowd too many specimens in the same vessel. In all 
cases, since tbe preserving liquor becomes diluted and 



deteriorated by the blood and other fluids of the recent 









r- 



t-* 



T 



376 



ZOOLOGY 



[Sect. XI 



specimeiij such specimen should be removed after a few 
days, according to'' the temperature, into fresh spirit or 
solution. 



The larger mammals must be skinned, taking care that 
the head and feet remain attached to the skin according 



to the directions subsequently glven« Such skins, if trans- 



mitted eitr^^r- in spirits or the arsenical solution No. II., 
usually arrive in excellent condition, and maybe mounted 
as well as if recently taken off tlie animal, which is never 
the case with such as hiwe been dried. If the circumstances 
under which the animal is taken will admit of preserving 
the skeleton, that ought to l>e done ; for its importance 
is of great moment in a physiological point of view, 
not only as relating to the orgaaii;^ation of the animal, 
but as a measure of comparison with other living species, 
and with those which are extinct and only found in a fossil 
state. If want of space or other circumstances forbid the 



pr 






rvation of the entire skeleton, the skull is the most 



valuable part to select, and it should be preserved when- 



. -1 



ever tne opportunity occurs. 



The mode of preparing the skull of a mam-mal for the 
.....seum is to place the head in a jar of water until the 



soft parts become detached by maceration and putrefac- 



tion ; being then washed clean, care being taken to pre- 



vent the loss of the small ear-bones^ tongue-bone, or loose 
teeth, it should bf^ placed in fresh water, and the water 

until the skull becomes free frout 

.nd 




frequently 

offensive smell : it should then be exposed to the sun a 



air, and will in a few days become beautifully white. 
But this process is not requisite for the mere preservation 
and transmit Jon of skulls : if the brain be broken down 



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Sect XL] 



ZOOLOGY. 



377 



j 
4^ 



and extracted by means of a small flattened stick through 
the " foramen magnum/' and the soft parts cut away, it 
may be simply dried, with the lower jaw and hyoid bone 
attached^ and packed in branj sawdust, or dried sea-weed. 
When the entire head of a duplicate mammal is pre- 
served in strong spirit, for the examination of the brain 
and organs of sense, a small portion of the cranium should 

r 

be removed, and the membranes of the brain carefully cut 

F 

to £rive the alcohol access to that organ. 



r 






p^- 




s 



The oesophagus and stomach should be preserved in 
pirit or the solution No. I., with a portion of the duode- 
num ; and the CcEcum, if any, with a sma.ll portion of the 
ileum and colon. If the animal be not too large, it will 
be preferable to cut ofl' from the mesentery the jejunum 
and ileum, which (after their length and circumference 
and the nature of their contents have been ascertained and 
noted) may be thrown aw^ay, and then to strip down from 
the spine the contents of the abdomen, beginning at the 



^■^ 



diaphragm, so as to have the liver, stomach, spleen, pan- 
creas, colon, &c., all with their attachments, taken out 
together as low as the rectum, where it lies in the pelvis, 
and, after being cleansed and the contents examined^ put 
into spirits or solution No, I. 

The heart and lungs may be preserved together, or, if 



too large, the heart alone with the large blood-vesse 

The contents of the pelvis, viz., the bladder and rectum, 
with the internal parts of generation, both male and 



female ; also the external parts, not separated from the 
internal, with a large portion of the surrounding skin, 
should be left attached in their natural state, and pre- 
served in spirit or solution. 



I- 



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H^ -S ^.^ 



o7 




ZOOLOGY. 



Pect XI. 



S 



If the female parte are in a state of impregnation, the 
whole are to be taken out as before described, without 
opening the uterus imless for the purpose of admitting 
the spirit for the preservation of its contents, v/here of 



large size. 

The young of very large animals, as whales, seals^ the 
walrus, elephants* -.ic, and all foetuses or abortions, should 
be preseryed entire : but if a young cetaceous animal be too 
large, the tail may be cut off below the anus, and the 
body put into spirit ; and if this should be too big for one 
cask, the head may be taken off and preserved in another. 

Of a full-grown whale, or other large animal, the fol- 
lowing part^ should be preserved :— 

The eyes^ with the surrounding 
muscles and fat. in an entirt- mass. 




skin, their 
The organs of hear- 



m 




The brain. SectiouB of the spinal chord. 



n^ 



The 



supra-renal glands. The ganglions of the sympathetic 



nerve. The beginning of the aorta and pulmonary artery 
for the valves. 

The moanmse of the female, with part of the surround- 
ing skin ; also the ovaria and uterus. The foetus, when 
found ^n the belly ^ to be taken out with the whole of the 
uterus, vagina, ovaria, &c. 



tne 



•v^ 



as 



elude the anus with it 



■3 



In skinning quadrupeds the skull and leg bones should 
pay? be retained = The first incision should be made 
from, the breast along the middle of the abdomen : the 
skin is then easily separated from the body by the finger, 
occasionally helped with the ki.Ife. Upon reaching the 
legs, they should be cut through, the fore legs by the 



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Sect. XL] 



ZOO LO G Y . 



879 



shoulder bone, and the hind legs by the base of the thigh 
bone. The whole of the leg bones are to be left in their 



places, until the operation with the other part of the body 
is completed. In skinning the neck and head the skin 






must oe 



ned 



great 




taken, in 



separating the skin fr^"^ the head, that the ears and eye 



lids be not cut. The s^^H being drawn olf the head as 

separated from the 



far as the ears, the head should be 
neck^ and then freed from every particle of flesh, such as 
the tongue, &c. ; and the brain taken out by making an 
opening at the back of the skulL The next thing is to 
skin the legs and the tail. In these parts, as in the neck, 
the skin must be turned inside out : all the flesh then 



orne 




the skin over them, firsi 



1 



n Ai.iU. 



their places by re~drawin 

ing a little cotton or tow round the bones to prevent the 

skin adhering to them when it dries. 

In animals of moderate or larsre size, it will be neces- 



s 






ary to skin the face upwards, commencing from the lips 
in order that all the flesh may be removed from the bone 
of the face. 

In most colonies native assistants may be soon taught 
this process, and nothing more is necessary beyond washing 
and then wiping the skin tolerably dry, if it h to be put 
into spirit or solution : but if int-^^ded to be sent home 
dry, then the interior surface, with the bones, must be 
anointed with arsenical soap, and likewise the nostrils, ears, 
and lips, internally ; and the hair or fur ought to be wetted 
with a weak solution of corrosive sublimate. The skin 
should then be stuffed with tow or cotton, but not t'^jhtly 
so as to stretch it. 



^ 



a^ 



■ i^ 



^^'^^ 



380 



ZOOLOGY- 



[Soct, XI. 



In warm climates of course it is necessary to skin the 
animal immediately after death, and it is very desirable 
that the skin be kept in the shade. Large quadruped 



^kins should be immersed in a strong solution of alum, in 



^ 

^ 



which they may remain three or four days, and when 
taken out of the alum-water they should be w^ashed on 
the inner side wdth arsenical soap,* especially about the 
skull and bones of the fc^t; a painting -brush may be 
used for this purpose, and the soap should be mixed with 
water until it has the consistence of cream : a very small 
quantity of soap is sufficient ; it should not be used too 
freely. When it is ineon?enient to u^e alum-water, the 
pow'dered alum may be used in a dry state, and should 
be well rubbed over the whole of the inner side of the 
sk 



4n 



PacMnQ. — Great care should be taken in packing skins 



that they be thoroughly dry* They should be packed in 
wooden boxes, and some pieces of camphor must be placed 
with them in order to prevent the attacks of moths. 
Toba< 






5*3 






is often used, but does not always answer the 
intended purpose. When soldered up in tin boxes speci- 
mens often become mouldy, and are sometimes perfectly 
destroyed by the damp. 

Labelling specimens. — The labels or numbers should 
never be placed on the paper or wrapper in which a speci- 
men is enclosed ; in this case they often become acci- 
dentally transferred, especially in the examination which 
the specimens undergo at the custom-house, &c. Small 



parchment labels, wdth the locality of the specimens, should 
be securely tied to the legs or some other convenient part ; 

* See p. 372. 



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Sect. XI.l 



ZOOLOGY. 



381 



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a number corresponding \vith the collector's notc«book 
should also be attached ; this number may be stamped on 
a small piece of sheet-lead or trebly thick tin foil ; when 
specimens are preserved in spirit the latter must be used^ 
since the former will corrode and injure the specimens. 
A set of steel dies from to 9, with a small punch, should 



be got, when the numbers may at any time be stamped in 



a line, with a hole punched in front of each, and then cut 
off with a pair of scissors as wanted. 

Notes, — The collector should note down the colour of 
the eyes or irides^ and the form of the pupil, and the 
colours of those parts, the naked parts, e. g. which are 
likely to be altered in drying : also the form of the head 
and muzzle, the habitual position of the ears and taiL 
The exact locality in which the several specimens were 
procured is of great importance in the determination of 
the laws of geographical distribution of mammalia : and 
not only the country, but the nature of the country, its 
elevation and geological character, as nearly as can be 
ascertained. Also the degree of commonness of the 



animal and 



any 



of its known habiis 



^"5 and the native 



name. 



Neither shape nor colour can be preserved in the dried 
skins of whales, porpoises, &c., nor can they be ascertained 
from skins alone, without the aid of drawings taken from 
the specimens in a fresh state. Skins of the cetaceans 
(whale and porpoise tribe), and of seals, are, nevertheless, 
great desiderata for public museums, and with the addi- 
tion of sketches and notes of the recent animal, are espe- 
cially recommended to the attention of the naturalist 



voyager. The skulls or skeletons of all the species of th 



_ ^ 



iit^. 






£>- 



r-. 



£ 



*1^ 



382 



ZOOLOGY. 



[Sect. XI. 



Seel 



soTithern cetaceans and seals slioiild be preserved, tbe sex 



oe 



I 



As the oreater portion of the smaller mammals are of 
nocturnal habits they can seldom be procured without the 
aid of traps, which must be baited some with flesh, or a 
lead bird, some with cheese, bread, fruits, ^c. ; small 
pits, widest at the bottom, and baited, often serve to 

entrap small quadrupeds. 

Necessary materiohfor determining Species. — In almost 
all cases the zoologist is desirous of examinhig more than 

pecimen— in fact, of having before him at least a 



sT)ecimen of the male, female, and young animal, and also 



one or two skulls, before he can give a satisfactory 



description of a new species, that is, such a description 
that the animal may be with tolerable certainty identified 
throush its means. When one specimen only can be 
procurcdj the skull should not be injured ; a little extra 
time is well spent in removing the brain through the 
occiplul opening, the baok part of the skull being of 
great importance. When the species are small, and 
several specimens can be procured, one at least should 
always be preserved in spirit or solution. 



The Human Race. 

The chief points to which the attention of the philo- 
sopL' J and zoological voyager should be directed towards 
the advancement of this most important branch of Natural 
History are included in the following queries : 

What is the average or general stature and weight of the individuals^ 
and ike extreme cases ? 

Is there any prevailing disproportion iu the size of the head ? ot the 

I- ^er or lo^er extremities ? 



V 

stra 

Ii 

ova 

alsc 

r 

any 

ticu 



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dis 

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rel 
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Sect. XL] 



ZOOLOGY, 






1 



V 






a 



Mti- 



l 



Aff^ 



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A 



)C 






.lU 



ytl- 



What is the prevailmg complexion, and the colour of the eyes? 

What is the coloui- of the hair, and its character, as fine or coarse, 
straight, curled, or ■wooUy ? 

Is the hoad round or elongated in either direction? Is the face broad, 
ovalj lozenge-shaped, or of any other marked form? (A profile and 
also a front view should be given.) 

Does infanticide occur, and to what causCvS is it to be referred? 

What is the practice as to dressing and cradling children ? Are there 
any circumstances connected ^vith it tending to modify the form of par- 
ticular partSj €. g.y the head or the feet? 

Are the children easily reared ? 

At Tfvhat age does puberty cake place ? 

Are births of more than one child common ? What is the proportion 
of sexes at birth and among adults ? 

To >vhut age do the females corifmue to bear children ? And for -^hat 
period are they in the habit of suckling them? 

What is the menstrual period, and what the time of utero-gestation ? 

What are the ceremonies and practices connected with marriage ? 

Is polygamy practised, and to what extent ? 

Is divorce tolerated, or frequent? 

How are widows treated ? 

What is the prevailing food of the people? Describe their modes of 
cooking, 

Yv'hat number of meals do they make, and what is their capacity for 
abstinence, and for temporary or sustained exertion ? 

Describe the kind and materials of dress; and any v-actice of tattoo- 
ing or otherwise modifying the person for the sake of ornament or 
distinction. 

Do the people appear to be long or short lived ? State the ascertained 
cases of extreme old age. 

What is the general treatment of the sick, and the superstition, if any, 
connected with it? 

What are the prevailing forms of disease ? 
Do Entozoa prevail, and of what kind? 
How are the dead disposed of? 
What is the received idea respecting a future state ? 
What are the kinds of habitations in use amongst the people ? 
Have they any monuments; and of what kind >nnd for what object? 
Wirat are the domestic animals, if any? Whence derived, and 
whether degenerated or modified ? 

Note down any illustrative particulars of the government, policy, 
religion, superstitions, or sciences of the people ; their mode of noting or 
dividing time ; their mode of carrying on war, and favourite weapons. 






^^^j^ 






i**' 



384 



^ -OOLOGY. 



[Sect. XL 



See- 



In these researclies collect and preserve the skeletons, both human 
and of other animals that may be buried or preserved with man: with 
any works of art or implements. 

Besides the skeletons, or, at least, the skulls of aborigines of foreign 
countries; plaster casts of the head, the hands, and the feet should be 
taken ; and wherever the opportunity may occur, the brain should be 
preserved in strong alcohol. 



Important aids to the advancement of zoology may be 
rendered by the transport of liying animals, and more 
especially their transmission to the Menagerie of the 
Zoological Society of London, for which purpose the fol- 
lowing remarks have been contributed by a former Vice- 
President of the Society, William John Broderip, Esq., 

" In the endeavour to bring a captured animal home 
alive, it will be well to remember that the younger 
quadrupeds and birds are, — provided they are of an age 
to be separated from the mother with safety, — the greater 
wall be the chance of success in bringing them home in a 
thriving state. There is hardly any young vertebrated 
animal which iudlcious kindness will not render familiar. 

and should be fed 




The captive should be kept 
sparingly ; that is, it should have only sufficient to sustain 
it in health ; — all trash should be kept out of its reach 
and it should not be subjected to the capricious kind- 
ness or ill-treatment of strangers. 



*^ Herbivorous quadrupeds, and hard-billed or seed- 
eating birds, are obviously most easily accommodated 

F 

during a voyage ; but carnivorous anim.als and insecti- 
vorous birds may be transported without much difficulty 
by paying attention to their food and habits. 

'' It would be far from impracticable for ingenuity to 






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Sect. XI.] 



ZOOLOGY. 



38 




devise a mode of introduciDg even humming-birds alive 
into this country. A strict attention to temperature, and 
the aid of an artificial florist, might effect this. If it be 



found that the birds will not feed out of little troughsj 
quills, or tubes of coloured paper,* the flowers which are 
observed to be their favourites might he imitated, and 
liquefied honey, or even sugar and water, might be placed 
m a little reservoir in the site of the nectarium. To take 
these brilliant creatures alive is not difficulty, if the fol- 
lowing method be adopted. Some plant (the aloe for 



\ 



instance), the flowers of which are particularly attractive 
to the humming-birds, being selected, all the bunches of 
blossom, save one or two, should be broken off in the 




evening after the birds 



have retired. These bunches 
should be enclosed in light bamboo trap-cages, with large 
open falling doors kept up by strings, to be held by a 
person in concealment. A little before the usual time of 
the appearance of the humming-birds, the bird-catcher 
must be in his hiding-place with the door-strings in his 
hand, and when he finds his prize busily employed about 
the enclosed flower, he must drop the door and secure his 

Mr. Bullock tried this plan with great success ; 
and, while on this subject, it may not be irrelevant (as 
connected with their diet) to state, that he saw these 
birds frequently take insects out of the spiders' webs, 
where they lay entangled, and swallow them ; and that 

* Captain Lyon, in his ' Journal of a Residence, &c., in the Renablic 
of Mexico,' p. 212, states that he kept a humming-bird for nearly a 
month on sugar and water, slightly impregnated with saffroij. It greedily 
sucked this mixture from a small quiil; and the Captain adds, that he is 
sure that, with constant attention, these little creatures mieht be kept for 



prey 



a long time. 



S 



^ -M- _ - >ri^ B- 




386 



ZOOLOGY. 



[Sect. XI. 



eome 




o^ 



has observed the remains of insects 



crops of some of those spec 



a 



are 




ifted with 



<- 
tt 



such 

well. Turtles 



that 



/ 

V 



r) and alligators are 



( 



^"* 

-* 



the other, wiiuuat any provisiou ; and, after 



ported almost without trouble. It is not 
uncommon for those who touch at the Gallapagos, where 
great land-tortoises abound, to put them into dry casks, 

one over 

many weeks, they are found not only ahve, but in excel- 
lent condition for the table, where they are said to exceed 
turtle in delicacy of flavour. 

" Guanas, chamajleons, together with others of the lizard 
tribe, and all serpents, bear abstinence from food for a 

time, and are brought from their native countries 

with little trouble. 

" Insects mav be taken in the caterpillar stage when 
about to enter the chrysalis state, and, in this manner, 
may attain their imago or perfect development, either on 
the voyage, or after their arrival, by attention to their 
habits, and to the temperature of their natural locality. 



lor 




(land-shells) 



"The terrestrial or pulmoniferous Mollusca 
mav be bruu^lit over alive with ease. When they show a 
disposition to bybernate, by sticking firmly to the side of 
tlie box or vessel wherein they may be, and at the same 
time throwing out the thick parchment-like secretion, 
which serves many of the species instead of a true oper- 
culum, they should not be disturbed, but must be kept 
dry, and, if possible, excluded from the air. Many 
species have been thus accidentally imported. Bulinus 



I, 



•ti,. . 



Sect, XL] 



ZOOLOGY. 




Rf 



\^' 



f 




« 1 



:" ^ ^ 



r 



• v 



I 



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1 



1 



* 






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it ■ 



yi 



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IVl V 



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r 

I. 






undatm was brought sticlcing to timber from the West- 
India islands into Liverpool, and is now nat^xialized in 



1 



iiymg 



the woods near that town. TLe author possessed 
specimens of Bidinus rosaceusy which had been brought to 



England by Captain King and Lieutenant Graves, R.N.j 




from Chiloe, and were in full vigour, thongh the animals 
had been packed up in cottOHj with the collection of shells, 
one for eighteen months^ and another for two years. lie 
now possesses one in good healthy brought h^- 
Cuming, which had been packed up for a 1 
Testacelbts and other 
viously. 

" By strict attention to changing the sea-water, which 
very soon becomes unfit for respiration when put into a 
vessel, marine conchifera^ moUusca^ and Crustacea mio'ht 
be brought home alive, and an 




had been imported pre 



opportunity given of 



studying their organization much more satisfactorily than 
can be done by a mere post-mortem examination, 

" The land-crab of the West Indies has been brought 
over with success. A pair of them were exhibited, in fall 
vigour, for a few weeks at the end of ^summer, in one of 
the enclosures open to the air, at the Zoological Gardens," 

should always be accompanied 



J 



Specimens of Fossils 

with part of the rock in which they occur, whether stone 
clay, or sand, &c. 

All fossils, without exception, may be brought home, in 
large number and ([uantity. 



gra 



ditiou as to freshness or decomposition ; whether they 
resemble those of the adjacent coast or seas ; the mode of 
their occurrence : whether rcgularlv interstratified with 



s 2 



»r^ 





2OOL0GY. 



[Sect. XL 



clay or stone ; in patches, or continuouBly, on the sides of 
hills, or of clifts. and at what altitudes above the sea. 



Stat<^ whether the fossils found in any given situation 



are all marine, terrestrialj or fluviatile : mixed, or in dis- 



tinct groims ; and, if mixed, in what proportions. 



Oh 



fresh 



water and marine shells in bodies of water near the shore, 
or in lakes at a distance from it. 

Inquire whether bones of mammalia occur among them. 



Note the brackishness of the water ; — whether it com- 
municates or not with the sea. State any differences of 
the animals from those of ])urely fresh, and of bait water. 

Observe carefully the position of fossils in the beds 

afford them. If corals, whether vertical or in- 



which 



clined ? If shells, are they disposed in layers parallel to 

the strata ? 

Notice whether testacea are carried up to cliffs by 
birds ; the quantity of shells thus accumulated, and their 
state of preservation. 

Notice the relative numbers of shells of the same species 

on the shores. 



Seek for and preserve all traces o{ fossil bones. 

Be careful to ascertain that thev are imbedded in the 

nxMmii. riof, IdnRP: or intermixed with the recent detritus. 



If any bones should be dredged up, note the place of 
tiieir occurrence^ latitude and longitude, its distance from 
any great rivers, whether within currents. 

Bones in caves. — Examine the materials forming the 

bottom of caves for bones. 

Bon: hreccia.' — Search for this in crevices. 

Observe all indications of coal, and collect specimens ; 



- 'c- 




V. 
^1 



•^ft. 




1 + 



1 
1 



^ \* 



« 1 



I 



Ji^ 



4t 



Sect. XT.1 



ZOOLOGY. 



88 J 



n 



note any traces of vegetable impresiilons In the roclcs, and 
preseiTe them oarefnlly. 

Seek with the niicrcscoBe for infusorial animals, both in 
a fossil and recent state. 



On the Use of the Microscope on board Ship. 
The following remarks embody the experience 



01 



Mr. 

Charles Darwin, F.R.S., on tliis subject, the importance; 
of which increases as the science of zoology advances. 

TliL- facility in examining the smaller invertebrate ani- 
mals, either alive or dead, depends mticli more on the form 
of the microscope used thaa would be at first expected. 
The chief requisite of a simple microscope for this purpose 
is strength, firmness, and especially a large stage ; the 
instruments generally sold in tliis country are much too 
small and weak. The 

to the upright column and have no movement ; besides 



sta2« 




V 

•I 



the strength thus gained, the stage is always at e 
the same height, which aids practice in the delicate move- 
ments of the hand. The stage should be able to receive 
saucers, three inches in internal diameter. A disc of 
blackened wood, with a piece of cork inlaid in the centre, 
made to drop into the same rim which receives the 
saucers, is usefrd for opaque and dry objects: there should 
also be a disc of metal of the same size, with a hole and 
rim in the centre to receive plates of glass, both flat and con- 
cave, in diameter one inch and a half, for dissecting minute 



lets 



objects ; a plate of glass of three inches diameter 
in too much light and is otherwise inconvenient. Close 
under the stage there should be a blackened diaphragm, 
to slip easily in and out, in order to shut off the ] 




^ 



U. 

3^^- 



^^ 






>^ 



.s 



390 



Z'^'^LOGY. 



[Sect. XI. 



completely ; in this diaphragm there may he a small 
orifice with a slide, to let in a pencil of light for small 
objects. The whole microscope should he screwed into a 
solid block of oak, and not into the lid of the box as is 

usual. 

The mirror should be capable of movement in every 

direction, and of sliding up and down the column ; on 



one side there must be a large concave mirror, and on 



the 



mirrors 



fitted water tight m caps, made to screw off and on : and 



two o 



:4Nl 



on a h~ng voyage, as salt water spilt on the mirror easl!: 
deadens the quicksilver. A small cap is very convenient 
to cover the mirror when not in use, and often saves it 
from being wet. The vertical shaft by which the lenses 



are moved up and down 




T (as ' 
form) 



^^^ 



^ s 

tX 



djiist- 



there should be on both sides large milled he 
such, there is no occasion for fine moYemeiits 
ment, which alwavs tend to weaken the instrument. The 
horizontal shaft should be capable of revolving, and 



(f 



right and left hands) , but the left milled head must be 



quite small, to allow of the cheek and eye approacliir;^ 
close to the lenses of high power. The horizontal shaft 



must come down to the stage. 



The most useful lenses are doublets of 1 inch and 
6-lOths of an inch (measiu*ed from the lower glass of the 



doublet) in focal distance ; a simple lens of 4 or 5-lOths 
of an inch is a very valuable power ; and, lastly, C:d- 
rington lenses (of the kind sold by Adie of Edinburgh), 









Sect. XI. 1 



1K)0L0GY 



391 



) 



c( 



\, 



\ 



(^ «' J 



u 



flfk 




— * 



i 



) 



1 

1 I 




.fi- 



of l-lOth, l-i5tli, and l-20th foeal dbtaiices, liaye Icen 
found most useful by two of the most eminent naturalists 
in England. With a little practice it is not difficult ^o 
dissect under the 1-lOth lens, and some succeed under 
the l"20th. A perse, not having a compound microscope 

All 



might procure a l-30th of an inch Codrington lens 



ast doublet) ghoi 
same rin^: the 



e 



made to 



on 



sheft. 



opposite end of the horizontal 
The best sauce. 3 have a flat glass bottom, with 

hould 



c biiU 



thin upright metal sides (silvered wnltbin) ; the 
be at least tour of themj being in depth (inside measure) 
S-lOthsj 5-lOths, 7-lOths, and a whole inch. Circular 

of fine-textured cork, of the size of the saucers 



i'T - -_- 



1^' 



cr»ij 



(wit 



of 




o 



bjects 



ad of transmitted light 



and 



lace-needles should 



to be dissected by direct inst 

For this end short fine pins 

b^ procured ; wherever it is possible, the animal ought 

to be fixed to the cork under water. Of the smaller 



plates of gla^:^ of an inch and a half in diameter^ some 
should be flat and some slightly concave ; the latter are 
very useful — saucers of this small diameter are incon- 
venient. 

The simplest and most useful instniments for minute 
dissection are the triangular glove-needles, which with a 
little cotton-wool and sealing wax can be easily fixed into 
pieces of large-bored thermometer tubes ; a stock of 



With 



tubes and needles should be taken on a voyage. 

these needles (by keeping the object only just immersed 

in a drop of water, which can be regidated by the suction 






392 



ZOOLOGY. 



[Sect, XI. 




-paper), wonderfully minute objects can be dis- 
sected ; needles bent at their tips are convenient for 
some purposes. Arm supports are useful in minute dis- 
sections; two blocks of wood with inclined surfaces, 
coming up a little below the level of the stage, and 
resting partly on the stand of the microscope, can be 
mr-^e by a common carpenter. As it is often rather 
dark in the cabins of ships, a large bull's-eye glass on a 
stand (such as arc sold with most compound microscopes) 
would be most useful to condense the light from a lamp 
on an opaque object, or to increase it when transmitted. 
Besides the needles, fine pointed forceps, pointed scissors, 
and eye scalpels are requisite, Tlie French use an 
instrument called a microtome, and consider it most 
useful : others prefer finely pointed scissors, with one 
leg long and thick, to be held like a pen, and the other 
quite short, to be pressed by the fore- finger, and kept 
open by a spring. A live-box to act as a compressor, or 
still better a proper compressor closed by a screw, and 
both made to drop into the rim of the stage, are valuable 



aids for making out the structure of transparent animals 



or organs. The observer should be provided with three 
slips of glass, or still better with three circular plates, made 
to drop into the stage of his microscope, and graduated 
into tenths, hundredths, and thousandths of an inch, to 
=erve as micrometers, on which to place and measure any 



fc^ 



object 



le is examining. Some watch-glasses are very 
as temporary receptacles for small sea-animals. 
Minute parts after dissection can be preserved for years 



useful 



m 






vy vjcak spirits of wine 



placed on slips of mass 



D 



by covering them, when 
by ^mall portions of very thin 



f 



^ 

Y 



[ 



Sect. XI.l 



ZOOLOGY. 



393 




glass (both sold 
edges with crold-size.* 



:)j and cementing the 




^Vhen 



opportunity concur for tlie anato- 



mical examination of an animal, the follovving notes 



or heads of observation will guide the dissector to the 




facts which it is most 
down. 




to determine and note 



F 



No. 



Date 



18 



Notes of 
Animars Name 



Sex 



Age 



Weight 



Length of body, from extremity of jaws to root of tail 



of head 



of tail 



Situation of testes 



— of preputial orifice 

— of vaginal orifice 



of anus 

and number of mammes 



Abdominal muscles 



ring 



simple 



lengrth 
Observations, 



Stomach 



compl 



number of sacs 
Ohs. 



Omentum 
Mesentery 



( length 



Intestines 



" of small 

- of caecum 

- of large 



Observations 



Anus 



greatest circumference 



relative size 



greatf^ circumference 



of small 
of cseeuni 
of large 



glands 



t^ 






* A microscope such as here described, and most of the apparatus, 

can be seen at Messrs. Smith and Beck's, opticians, of Colman Street^ 
London. 

s 3 



L^■ 



J 

I 



394 



ZOOLOGY. 



[Sect. XI. 



I 






t 

1 



Cloaca 



Liver 



situation 
number of lobes 

weight 

Ohservations 



Gall-bladder, size 

structare 

Bile, enters intestine 



situation 



Pancreas 



Spleen 



Lungs 



term 

situation 

its secretion, enters intestine 



Situation 

form 
I weight 
si^aation 
length 



breadth, right 



left 



< 



weight 



of lobes, right 
^ structure, air cells, &c. 



left 



Branchige 



Heart 



situation 

weight 

length 

shape and structure 



breadth 



Vena^ cavee 

Aorta, primary branches 

Trachea, number of rings 

Larynx 

Phary 

Epiglottis 

Thyroid Glands 

Salivary dands 



k 



Structure 



a* O 



TongoGj length 

Nostrils 
Kve-lids 

Pupil, form 
Lachrymal gland 

E 

Brain, weight 

Spinal cord, length 
Supra-renal glands 



papillae 



/ 






form, &c 




'X- >rf 



H * J 



I 



-Sect. Xl.] 



ZOOLOGY- 



39 



^ 



I 



Kidneys 



situation 
form 



length 






weight of both 

papilla*, number and form 



Ureters terminate 



Urinary bladder 



situation 

size 

shape 



Testes 



size 



structure 



Vasa detreutia terminate 



Yesicula; seminales 



size 

structure 
terminate 



prostate 



size 
structure 

terminate 

size 



Cowper's glands { structure 



I terminate 



Penis 
Urethra 



length 



muscie 



Ovaries 



situation 

size 

shape 

Observations 

length of cornua 






Uterus 



of Fallopian tubes 
of body 



Vagina 



position 



< ^ 



Oviduct 



length 

form 
termination 



Peculiarities of muscles 



air-sacs 



glandular organs 



Morbid appearances 
Calculi 
Entozoa 
Epizoa 






I 



1 



I 



t 



i 



396 



ZOOLOGY. 



[Sect. XI. 



General Directions to he observed during a VoyageJ^ 
The towing-nets should be kept overboard whenever it 



is practieabie, and the dredge should be used persever- 



ingly in soundings. 



o 



The anchor sliould be inspected as soon as it arrives 
at the surface, especially if the holding ground be mud. 



Th^ finest sheik have been lifted on the flukes of anchors. 
The cable should also undergo an examination. 

Let the arming of the lead be narrowly observed, and 
let the men have orders to preserve anything that may be 
sticking to the arming, the lead itself, or the lead line- 
Floating masses of sea*weed, especially sargasso, should 
be carefully searched ; and if one of those tangled 
natural rafts, which are often carried adrift from great 
rivers, sliovild be seen, it should be examined minutely, 
and the animals, plants^ and seeds which it may be trans- 
porting to colonize some newly-formed island, should be 
preserved, if possible, or, at all events, accurately noted. 
Whenever a new marine sp<^cies, or one whose habits 
are unknow^n, is obtained, it should be placed in sea- 






ter, and, if practicable, a drawing should be made of 



it while yet alive, with a note statin 







whether it is gre- 
or solitary — phosphorescent or not — and giving 



the locality, the temperature, the state of the weather, 
the depth of water^ and the time where and w^hen it ., 
captured. The sea w^ater in which living marine animals 



kA>*^ 



are confined 



kJ 



hould be often changed 



for it speedily 



becomes unfit for life. 



* From 'Hints -r CoUectbg/ &c., by Wm. John Broclerip, Esq., 



F,E.S. 




>, 






; 



* 




Sect. XL] 



ZOOLOGY 



397 



.^ 



i 

4 



r 



1^ 



1 



M* 



w 



n 




> 

if 



^ 



u 



^- 



the 



1 



r«r 



r 



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1„ * 



^■ 



t-. 



(, 



If a turtle {Chelone) be taken, the shell should be 



examined for parasitic barnacles {Chdonobia) and other 
adhesions. The specimens ought not to be scraped off; 
but the plate of shell to which they are affixed should be 



taken out, and the whole should be preserved together. 



Whales should be searched for CoroimlfE^ Tiihieinellc^^ 
&c- : they should be left, ''i they are founds in the skin 
and blubber of the animal, and the piece with its contents 
should be plunged in spirits. 

The stomachs and intestines of those fishes and birds 
which are killed during the voyage should be inspected 
before they are thrown away ; not only for the purpo.se of 



noting their food, but for the chance of finding undigested 
shells, &c,, and in .search of Entozoa. The feathers of 
birds should be examined with a view to ascertain whether 



any parasitic insects, any ova of fish or te 
seeds of plants, adhere to their plu 






:, or any 

Their crops 

will often be found stored with fruits and seeds, which 
they disseminate in their flight. 

Particular attention should be paid m the appearai 






ance 



V 



of birds or insects, as well as to the direction whence 

they seem to come, with a view to the elucidation of their 
migration. 

By placing in the sea clean planks of wood, iLe rate of 
growth of Teredo navalis, and of the Cirripcdia, together 
with the ravages made by the former, in a dven time, 
may be ascertained. Serpulce will probably be found on 
the board also, and, perhaps, other shells. This experi-- 
ment should be repeated whenever an opportunity occurs, 
and in different localities and climates. Some of the 
planks should be painted, others covered with pitch, 



f 



■J^ 



i 



I 



I 

i 



tJVO 



ZOOLOGY. 



[Sect. XI. 



others studded closely with copper and other nails, and 
some should be In their natural state. 

When on shore in search of terrestrial moUusca (land- 
shellsK the collector must not he content with a close 
examination of the trunks, leaves, and stems of trees, and 
other plants, but must turn up all decayed vegetable 
substnnces, especially in moist places, and there dig into 
the earth, more particularly about the roots of trees, and 
under overshadowing bushes and shrubs. Stones must 
be lifted, — herbaceous plants must be pulled up and 
their roots inspected,-— and, if the boat's crew be at hand, 
fallen trunks of trees should be turned over with hand- 
spikes. All ova must be preserved; and the height 
above the level of the sea at which the specimens were 
taken, and the plants on which any of them were feeding, 
must be noted. In the latter case the plants should be 
preserved in an herbarium, and numbered as directed 
under the head of insects. 



No 



'J 



should be passed without examining the rushes and other 
plants there growing, for fresh-water testacea. At the 
proper season their ova may be found adhering to living 
and dead stems of plants, leaves, &c. 

No bird, insect, shell, nor any other zoological spe- 
cimen should be neglected because it does not strike the 
eye as beautiful, or because it is small and appears to be 




S 



cimens 



paclced, it should never be opened till it arrives at the 
place of its destination. If it is wished to have a few 
duplicates at hand, for the purpose of •- 



xchange with other 






V 



J 






i 



.; 




! 



*^ 



^♦^ 



11 



^ 




ttoA 



1 1 



^■ 



ii 



• of 



iv 



p 



\% 



• * - 



■d 






1 I f 




[ 



•• f 






» 



I 



Sect XL] 



ZOOLOGY, 



399 



collectors who may be met during the voyage, some 
specimens should be- set aside for that purpose. All 
observations should be noted down while the impression 

with the subjects actually 



pOS; 



5 



before the observer. 



When an animal is seen afloat, and is remarkable for 



1 



.gnitude 



iS 



not captured. 



mode, course* and 



^'1 



progression 



be noted at the time with the utmost accuracy. If the 

zoological 



observer 



has not 



the 



rmininof the snecies from the 



phenomena., he should abstain from giving the animal any 
special name. A shot fired, if it do not hit, may so alarm 
the creature as to cause some sudden movement which 
may reveal more of its true naiure. 



^/»4l. 



» ■" 



1' 







^^ 







\ 



^ 



n?^ 



\ 



i 

f 



400 ) 



Section XII. 



BOTANY 



By sir WILLIAM HOOKER, K,H., D.C.L., F.R.S., &c. &c., 

AiSD Director of^ie Royal Gardens of Kew. 

Botany is a science whicK requires to be studied at 
home as well as in the field. For this reason it is highly 



• • 



o 



ign 



desirable that persons 
not only obtain information on the spot respecting the 
j>lants and their uses and properties, but that they should 
transmit to this country ample collections of welUdried 
specimens^ with the rarer fruits and seeds^ and all sorts 



of interesting vegetable products. By the latter expres- 



\^ 



sion we mean not only gums and resins^ drugs and dye- 



ffsj but whatever may be 



origin In food and clothins 




of vegetable 



_,i building (the various 
kinds of woods), utensils, &c. We therefore first offer a 
few plain instructions for collecting and transporting 
plants in foreign Ian 






Living Plants for Cultivation. 

Plants for cultivation in our Eiiropeaii gardens may be 
introduced either as seeds, bulbs, tubers, cuttings, or rooted 

plants. 

Seeds, bulbs, and tubers are easily collected, and as 
easily transmitted to Europe from very distant countries. 



\ 






^ 



4 

r 



I 



c 



\ 



I 
] 



] 

1 






] 

1 



3 



( 



< 



% 



1 






4 

i 



} 




I 



Sect. XII.J 



BOTANY. 



401 



P 




f 




» 



\ 



} * 



t . 



^ 



»t 



Ft 



t* 



. - ^ 



*f" 



u 



*' 



) 



The first, seeds^ require to be gathered quite ripe ; to be 



wrapped, a quantity of each, in paper (couxiuon brown 
paper is as good as any), done up in a parcel, and kept, if 
possible, while on board-ship in <m airy part of the cabin. 
Bulbs and tubers should be taken up when the foliaj^e 



has withered, and, if well dried, they m 
the same wav as seeds. 



be packed in 



(7w^fz/?^5.— Generally speaking it is yain to attempt 
sending cuttings of plants to a distance : they soon perish. 
But this is not the case with the greater number of suc- 
culent plants, those with thick and firm fleshv stems and 
leaves. Such are many of the Cactus tribe in South 



^Vmerica ; the various succulents of South Africa, 



Aloes y Euph 



Stapelia 

Housch 



Meserahry anther iium 
kind, &c, Manv o 



as 



or 



Bromelia^ or Pine-apple tribe, and the Agaves^ or Ame- 
rican Aloes, will sur\dve a long time as cuttings. The 
cuttings should be taken off, if possible, where there is a 
contraction or articulation of the stem, or at the settin 
on of a branch : the wound ouglit to be dried by exposure 
to the sun ; and all such cuttings may be |)acked in a 
box, with paper wrapped about them, or any dry elasti 
substance to keep them steady. 




c 



Plant 



as 



are of a succulent nature, small Cactuses, Aloes, Bromelias, 



Zamias^ &c. 



5 



( 



valued in European stoves) the various Epiphytes or Air- 
plants, those numerous orcMdeous plants and others of 
the Arum tribe, which clothe the trunks and branches of 
trees in tropical countries :— all these will bear a long 
voyage if removed with their roots and stowed in a box. 



--4 



Lrf^ 



l"- 



402 



BOTANY. 



[Sect XII, 



like the cuttings above described, the larger kinds sur- 
rounded ^ith dry straw. But plants when taken up with 
their roots (and young ones should be preferred) can 



ac 



plant-r-'^ses, now generally known and most deserve Uy 
esteemed. Tliese cabcs are glazed at the top or roof, so 
as to be in fact portable greenhouses. The plants should 
be established in the cases a few days before sending 
them off, secured by splines, so as to confiiie the roots in 
the soil in the event of the box being overturned, and 
moderately watered : the lid is then fastened with putty 
and screws, and the case being placed on the deck of a 
vessel so as to be exposed to the light, which is an in- 
dispensable rcquLsite, will require no watering nor any 



attention (unless 
the entire voyage. 




broken^ 



On Preserving Plants for the Ileroarium. 

This is by no means the difficult process which many 
have imagined. Tlie object is to prepare specimens in 
such a manner that their moisture may be quickly ab- 
sorbed, the Ciilours, so far as possible, preserved, and such 
a degree of pressure imparted, that they may not curl in 

drying. 

these purposes provide a quantity of paper of 

moderate folio size and rather absorbent quality 
brown or stout grey paper answers the purpose exceed- 
ingly well. The best of all, and it is not expensive, is 
Bentall's botanical paper, 16 inclics by 10, which costs 
(folded) 15.S. a ream, or, 
20 inches by 12, at 21s. 



For 



J 



per 



It is sold by New 



n 



t 






Sec 



ma 
ho 

th: 

IB 

pla 

pr< 

toj 
an 
oil 

jT.r 

off 

lei 
flo 
Lc 

m; 
afi 



on 



ca 

sh 
ai 
ai 

t^ 



' - ^-E. 



ci 

ti] 
til 



in 







Ul ^" 



m. 



t 



i 



r 



^' ! 



. 1 if" 



\'^ 



1. I, 



f 



( 



i 



Tl 



f 



I 

F 

f 



i 



I 



I 



* 



Sect. XII.] 



BOTANY. 



403 



man, Great Devonshire Street, Bishopsgate Street, 
London. Two boards are requisite^ of the same size as 



the 



the other for the bottom of the 



mass of papers. Some pieces of pasteboard (or millboard) 
placed between the Sj^acimens^ if these are nuinerons or 
particularly thick and woody^ are yery usefuL For 
pressure nothing is better than a heavy w^eight on the 
topmost board, or, while travelling, three leathiern straps 

transversely, and 




ather your speci 



and buckles, two to bind the board ;^ 

one longitudinally. Thus provided, 

r^^ns, if the plant be small, root and stem ; if large, take 

off portions of the branches, a foot or rather mure in 

length, always selecting those which are slender and in 

flower, or in a more or less advanced stp^^^ of fruit. 

Loijg, slender plants, as grasses^ sedges^ and maiiyjfera^-, 



may be doubled once or twice. Place them, as quickly 
after being gathered as you can, side by side, but never 



one upon the other, on the same sheet of paper, takin 



care that one part be not materially thicker than the 
other, iMi(l lay over the specimens one, two, thi 




^ee, or more 



sheets of paper, according to the thickness of your paper 
and of your plants ; and so on, layer above layer of paper 
and specimens, subjecting them to pressure. In a day or 
two, according to the more or less succulent nature of 
the plants and the heat and dryness of the soil and 



climate, remove them into fresh papers, twice or oftener 

- r 

till the moisture be absorbed, and dry the spar<^ papers in 
the sun or by a fire for future use. 

If the specimens cannot be laid down as soon as 
gathered, they should be deposited in a tin box, wl 



lich 



indeed is essential to the botanist when travellin 





^1 




^^- 



f^. 




^ ■« 



*:; 



404 



BOTANY- 



[Sect. XII. 



Seel 



tliere they may remain nmnjured for a day and niglitj 
srq.tposing the box to be well filled and secm^ely closed to 
prevent evaporation. Some very succulent plants, and 
others with fine but rigid leaves — the heath and p'nc 
tribe, for instance — require to be plunged for an instant 
into boiling water ere they are pressed. In this case the 
superabundant moisture must be absorbed by a cloth or 
by blotting-paper. 

When sufficiently dry the specimens should be put into 
dry paperSj one sheet or folio between each layer of 
plants, except they be unusually woody (which is the case 
with oaks and pines), and then more paper must be em- 
ployed, care being used to distribute the specimen? pretty 

be 



he 



V 

i. 



equally ovc^r the sheets, and thus a great many may 



safely arranged io a small compass. They are now ready for 
transport, either packed in boxes or covered with oil-cloth. 

Mosses and cryptogamous plants may be generally 
dried in the comrn^^n w^ay : those which orow in tufts 
should be separated by the hand to form neat specimens. 
Sea-weeds require a slight washing in fresh water, and 
common blotting-paper is the best for removing the mois- 
ture from this tribe of plants. 

It is almost needless to add that all plants^ whether 
living or dried, ought to be transmitted to Europe with 
the least possible delay : the latter, especially in hot or 

limates, are often soon destroyed by the depreda- 



moist c 



'.* 



n 9 



tions ot msects. 



The above short instructions refer solely to the collect- 
Ing and despatching !wi7i^ jHants and dried specimens ; m 
other words, the mec.ns of furnishing our gardens and tne 



\ 



f 



to^^ 
nie 
cal 

is 

inti 
wh: 
the 



see 



J 



ai 



s 



and 
the 
me] 
and 
ub 
Ind 

for 
1 
size 
ent] 



ft 



'Ul 



dry 
tur 



f 



r: 



bu 



{Pi 

alii 



b 



e 



(ace 



i 




m 



J 



i 



r 



•M'l 






i 
i 



I 



r 









Kibp I 


1 


1 


1 . 





K 



\ 



Sect. XII.] 



BOTANY, 



405 



herbarium. Another important branch of the science 
comes to be mentioned, hitherto much neglected, but 
towards which travellers will do well to contribute 



mean the museum of vegetable products, or it may be 
called the " Museum of Economic Botanv." 11.; desioii 



-^-^ 



is to bring together in one spot and to exhibit tho 
interesting vegetable products from all parts of the world 
which cannot be shown in the living plants of a 
the preserved ones of an herbarium. The publi 
see growing in our Botanic Gardens the 




ar 




or 



are 



i/' 



Palm 



and the Cow-tree from the Caraccas. 



'J 



'le interest of 
these is greatly enhanced when, in the same establish- 
ment, the curious and beautiful lace of the first, the fruit 
and ivory-like seeds of the second, and the cream-like 
substance of the third, used as nourishment by the 
Indians, can be inspected. 

Among the objects, therefore, which are to be collected 



for the museum are 
1. JFru 



size and possess any peculiarity of form and structure 



O 



p 



Palms, &c. &c. Ma 

( 



ture) previous to packing. Those which are about to 
burst open into valves, or to separate by their scales 
{Pvne-cones and Araucarias), should be bound round with 
a httle packthread. The soft and fleshy kinds can only 

I'lZ'!'!"''"'! '''. ^'j^^;-«^°^^^^ed bottles or jars, or casks 

m alcohol, as rum, arrack, or in 



( 



) 



meoi 



^s-- 



^ 



■-^ 



^^ 



406 



BOTANY. 



[Sect. XII. 



2. Flowers whicli are tery large or particularly fleshy, 



MS Siccus. These should 
ligneous acid. Among 
ed are, for instance, the 
Water-lilv, from the still 



tromca 



kinds 



3. Entire plants, or parts of them. Many have a very 
fleshy nature, and must be preserved whole in alcohol, or 
portions of the stem and branches, according to their ^ize, 
with flower and fruit ; such are the rare kinds of Stapelias, 



Mesemhryanthemr 



oft Pa 



Orchidacew, Misseltoe, Raffies\ 
Cactus^ Aphyteia, Balanopfiora, i 

of a similar ^ort. 

4. Trunks of tree^, portions and sections, particularly 

when they exhibit any remarkable structure, as Palms, 



otlier monocot yl edonous 



and many 
ZamiaSj Q 
play their union with the tre 



plants. 



-/^ 



\s 



e 



grow, 



5. 



J'Foods. Specimens of the kinds used in commerce, 
for veneering, cabinet-work, or other useful purposes : or 
such as recommend themselves by their beauty, hardness, 
or any other valuable quality. Specimens of wood should 
be truncheons, five or six inches long, and of such diameter 



as the plant allows. G 




it is advisable that 

(and fruit, 



t) 



proof of the precise tree or plant from which the latter 



IS 




6. Gums and resins^ eminently those employed in the 
arts or in domestic economy* 






Sect 



1 



and 



na 



^ 



ticu 

app 
am* 
dea 

pe 
diff 

whi 
tra^ 
as i 
wei 
thi? 
clot 
suh 
Th- 
ext 



of 



^ 



WOl 

a7ic 
of{ 

la 

in 

th 



1 ¥ 



a 



e 



onl 
the 



-r'^ 



tr" 



i 



• r 









^lll 



f 




il 



L 






^ , 



■^ 



^ 



W 



"i 



^J 



^ '- 



■Hit 



l^J»^ ^ ^ jj 



i 



^ y* ^^d^- 






^ 1 




\/' 



I A! 



** 



If 



I 



e^t 



^tifl; 



r 

■ F 

1' 



' '^ A 



t 






Sect. XIi.] 



BOTANY. 



407 



/ 



Dye-stuffs 



8. 3Iedicinal substances. These are of vast iinportance. 
and merit the atterition of travellers in eyery country. 
With respect to many, H is not yet known, except to the 
natiyes who collect and prepare them, what are the par- 
ticular plants that yield them. It is hoped the present 
application may be the means of dispelling this ignorance 
among scientific Europeans ; and that travellers will en- 
deavour to procure the substances and well-dried flowerino- 



.1 



specimens of the plants from which they are obtained. 

9. General products of vegetables. It is extremely 
difficultj perhaps impossible, to enumerate all of tLese 
which a museum ought to contain, but the enlightened 



traveller will form a tolerably correct judgment. Such 
as are useful to mankind cannot fail to be interesting. It 
were of course idle to exhibit every well-known object of 
this description, tea^ sugar ^ ^(ffee^ cocoa^ chocolate >, paper ^ 
clothing^ &c. ; but there are states even of these familiar 
substances which would prove both useful and instructive. 
The cane yielding sugar^ for instance, is advantageously 



exhibited, Paper^ again, is made from an infinite variety 
of vegetable substances ; and the different sort^s are well 
worth collecting, from that afforded by the papynis of the 
ancients (which gives the name) to what is manufactured 
of the inner bark of an East Indian Daphne (or Spurge- 
laurel\ and another from the pith of an unknown plant 
in China (the so-called rice-paper\ or the leaves of a 
Palm in India, or straw in North Amex^ica. Of all such, 
the several stages of preparation should be collected, not 
only as objects of .curiosity, but because they exemplify 
the progress of art and science. 



408 



BOTANY. 



[Sect. XII. 



-* 



A question will naturally suggest itself to the trav eller 
not previously versed in the vegetable productions of dif- 
ferent parts of the globe, " In what regions can I most 
iffectuallv serve the cause of botany ?" The answer is 
ready : In almost every portion of our world the inquiring 
mind will find objects for study ; though assuredly the 
less the coimtry has been tracked by Europeans and men 
of science, the more fertile it may be expected to prove 
in noveltv. But even where the coast has been visited 
and tolerablv accurately investigated, the interior, espe- 
cially if mountainous (and the loftier the mountains the 
more varied the vegetation), will afford an ample field 
for research. Even with regard to many frequented 
spots it has been truly observed that few persons visit 
them " with their eyes open." Thus, while some tra- 
vellers boldly assert that the vicinity of Aden is utterly 
destitute of vegetation, others have detected plants of 
very peculiar structure, and admirably adapted to such a 
locality •, and one estimable naturalist, Pakenhara Edge- 




has actually published a Florida entitle 
■lu-'s Botanizing Excursion at Aden,' givin 

during that brief 

tim.e, eleven of which are considered new to science. 
One has only to glance at a map of the world and it 



worthj Esq.. 
' Half an T 
an account of forty species 




will oe mstantiy se 
the botanist and th^ 



i^': 




eograpxier 



The extensive interior 



of South America, particularly towards the sources of the 




reat 



Africa 



? 



the table-lands of Thibet, with the northern declivities of 
the Himr -/lyan Mountains, the Chinese dominions, and 
many of the numerous islands of the Malayan Archi- 



i 



Sect 



%■ 



pelago 

it is »* 
look f< 



< 



ticulai 
this a 

tnany 
derive 



per 



fee 



lands, 
counti 



[N.B. ] 



ofth 



( 



sinia. 



resia 
forty- 
worth 



'esm 



come 
Specii 
are d( 



Ga 



fr 



I 



om 
G, 

afford 
this a 

indebte 



Sect XIL] 



BOTANY, 



409 



i*^ 




fe 



1 



f 



it 



i 




I r 

"the 



i 



I 



tUJU 



, i 



fX. 



Wt 



f 



r 



I ^ 



a^ 



rl^" 



T^ 1 



lk: 



• .J 
■J' 



< 



f. 



;i*' 



St 



L 



; .. 



r 



,f 



'f 



t^ 



)- 



t 

i^i*> 



4 



-^ 



1 I 



;■ 



*#" 



1, 



pelago, are still a ^crz-cz incognita to the naturalist. But 
it is not to such little traversed realms alone that wc 



nee 



d 



J, /egetable productions, par- 



look for new and interesting \ 

ticularly of the more useful kinds. The remainder of 
this article shall be devoted to a mention of some of the 
many plants, or peculiarities relating to the substances'' 
derived from them, which are yet unknown, oi 



very im- 



wn 



1 




je thenij according to their 



lands. We shall arrai: 
countries, as follows : 



Asia {including Australia). 

ilsM Being sent by way of the Red Sea, it may be remarked that some 
of the products, enumerated under this head, are derived from Abys- 
sinia, Arabia, or the East coast of Africa.! 



^ 



^- 



J 

Ammoniacum. — Determine the true origin of this f 



^ 
^ 



rsia, 



resin hy specimens of the plant yielding it in Pe 
forty-two miles south of Ispahan. Another kind is equally 
worthy of inquiry from Morocco in Africa, with the gum- 
resin and exact locality. 



-■ H 



Sagapenum. — A gum-resin 



its source ? It ^^ said to 



a Ferula. 



1 



come from Persia, and to be derived from 

Specimens of the plant with the gum-resin which it affords 
are desirable. 

Galhamim. ~^\^\iQ.iwQ obtained? It is brought to us 
from Singapore and Persia. 

6?aw%e.— Specimens in flower, and fruit of the plant 
affording the gamboge of Siam, and the mode of extracting 

this and other kinds of gamLuge, such as that of Cey- 
lon, &c. 

^ * For much of this Catalogue of Desiderata and Inquirenda I ^m 
indebted to notes from Dr. Royle, Dr. Pereiia, and Dr. E. D. Thomson. 

T 



■"-^^ 



t ? 



-^O-T 



410 



BO T ANY. 



[Sect TIL 



■^ 



r.^ 



m 



3 



Ammi Gum^ or Pw^?/ Varnish, said to be produced by 

Valeria Indica. 

Copal. — The origin of this gum-resin in India ? 

Bdellium. — The source of the Persian and African 
fahe myrrhs of this name, the locaUtics producing them, 
the native names^ and specimens both of the products and 

the plants, 

Oliba7innu — The above remarks apply to OHbanum. 

Elemi. — The source of the five varieties of Elemi, viz. : 



1. Holland Elemi. 
Elemi. in bamboos. 



2. Brazilian Elemi. 3. East Indian 

4-- Macula Elemi : and 5. Mexican 



Klem,i. Samples from the various countries, with the 
plants and native appellations, should be transmitted for 



verification. 

Tragacai 

Mount Lib^ 



Elemi 



-The tragacanths of Mount Ida and 



plants which yield them, nor has Tournefort's relation of 



the formation of this 



d 



^rroed 



It is still more important to ascertain if the tragacanth of 
Erzeroom is brought into British commerce, and whether 
it is yielded by the Astragalus strohiliferus. 

Senna--i:he source of the East Indian or Mocha 
Senna. Is it really the foliage of Cassia lanceolata? 

Catechu. — To observe the processes by which the 
various kinds of Catechu, Cutch, Terra Japonica, and 
Gambir are obtained ; and if from trees, whether from 



Unc 



Garni)! r. 



We want to identify the trees with the re- 



spective extracts. 

Cubehs.—J)QQ^ Piper Cubeba or Piper caninum 
yield cubebs ? If both, which gives the best ? 



m 



Java 



f 



\ 




^ 

J 



! ♦ 



iO V. 



^. 



'W 




0*" 



r 




» 



r 



^f 



r 1 



; rr 



ifcr 



^^lar 




, b; 



i'f.' 



J' 



flUl 



t 

fe 



t 



? 






K 



I' 



l^u. 



M 



'X 




? 



Sect. XII.] 



BOTANY. 



411 



r 



Cassia. — Botanical specimens of the plants ^^^'^n to yield 




Cassia bark in Kwagse^ China , Malabar, Egypt (and 

Cassia-buds of the OTOcers' shops.~To procure speci- 
mens of the bark in Cochiu-China and Japan^ and flower- 
ing specimens for the Her^'^rium. 

Mhuharb. —The true source of the medicinal rhubarb, 
and especially of the Batavian rhubarb. Strange to say. 
we are still in the dark respecting the real origin of this 
most valuable drug ! In this and all such cases the drug 






should be procured by one who is an eye-^witncss to it 
being gathered, and specimens of the foliage and fruit 
should accompany it, and be carefully dried for the 
Herbarium on the spot. 



Arrow-roof. — The sources of the East Indian arrow- 



X 

5 



S 



? 



^ 






root. It is made largely at Travancore. 



IP 



Salep 



•The different plants which yield salep in Asia 



Minor, Persia, and especially the best kinds. 

Aloes. — The true sources of the Soccotrine, Cleai 
Bombay, Hepatic, Eabi Indian, and Mocha Aloes. 






Minia 




orneo. — Whence is 



this solid oil or fat obtained ? Is it abundant or rare ? 

Gutta Percha, — That of Singapore is ascertained to 
be the product of a new plant, Isonandra Gutta of 
Hooker, in the ^ London Journal of Botany,' vol. vi. p, 
331, 463, tab. 17. The appearance of the inspissated 
gum which is imported from. Borneo under that name 
indicates a different source. Other Malay islar 



IS 



are 



plants. 



Percha^ but probably from yet other 



This should be 




m*'^ 



4/V-r 4 



the cliemical 



characters of the juice in a fresh state should be ascer- 
tained, and compared with those of caoutchouc. 

T 2 



L 



4:12 



feOTANY. 



[Sect. XII. 



Green Tea. — Is indigo or any other vegetable (iye used 
to colour the green tea in the northern provinces of 
China? Specimens of the plant and dye so employed 
are desiderata. Is turmeric or any yellow vegetable dye 
used in conjunction with it, or with Prussian blue ? 

Japan Wax, — The true source of this wax. 

Assafoetida. — From what species of Ferula is this 
extracted^ and bow? Does the same species yield the 
Tear Assa/wtida and the lumji ? Specimens of the one 
or several assafoetida plants should be procured, with 
the gum-resin produced by each species. 



JPatehaoiil 



Puchd Pat 



nown 



of comparatively recent introduction to Europe. It is 
referred to a plant now described by botanists under the 
name of Pogosteyrton Patchaouli ; but we are ignorant of 
the mode of its preparation and the exact locaUty where 
it is produced. 



Saqo of 



— Is it from a Cycas^ and what species ? 



Also specimens of sago in different stages of manufacture, 
with the trees yielding them^ from \h(i various parts of 
the Indian Archipelago ; so that we may identify the 
particular kinds of sago yielded by the several sago- 



palms. Is the Ceylon sago the granulated pith of the 
talipot'jjalm (Corypha umbrciculifera)9 

Korarima. — A large kind of cardamom, or aromatic 
fruit (an Amomum ?), found in the markets of Shoa, but 
probably the produce of a country farther to the west. 

^Scammon?/,— Particulars of tlie manufacture — or, to 

correctly — the adulteration of Scammony, 



speak more 



( 



carried on at Smyrna. AVhat is the purgative resin or 
um-resin fif any) v/liich i* mlrl^rl. with fhpt view of 




is added, with the view 



I 



■\ 



I 






*- 1^ w 



r^ ■- j_ 



i 



Ef ' 



•rn . 




L 



\ 




^^ 



m 



r 




k ■ 

i 



1-^ 



i 






• 



I 



* 




? 





1 



i» , 




. f.^ 



.^;', 



f 



*^ tf 



f 



F 



Sect. XTL] 



EOTAXY. 



413 



I 



Increasing tiic bi 
mixture ? 



ilk 



and 



the medicinal activity of 




C 



arnphor Oils. — There are two sorts : one 



brought 



from the East, does not deposit ci ystals by keeping ; the 
other does. Is the former the produce of Dryobalanops 
Camphora'i If so^ what is the source of the latter? Is 
it obtained from the foliage of Laurus Canqjhora (Cam- 



plwra officinariim^ Nees)^ or is it an artificially nianu 
factured article ? The camphor deposited is said to b 
similar to common camphor. 



Ki 



— All particulars of details about the 



manu- 



are desirable. 



Kino {Pterocarpus Marsupiiini) 



Turmeric. —The several commercial sorts of turmeric 

■ 

differ so much in external character as to throw doubt on 
the identity of their origin. Are they not the produce of 
several species of Curcuma ? Yv^ell-dried specimens, . 
at^cornpanying the root, 
different parts of India. 

The Grass- Oils. — The grasses used in India for afford- 



hould 



be transnntted from 



insf the oil 




srrass 



essence of verbena, or verbena-oil, to be ascertained, and 
samples sent home, with details of the manufacture. 

Storax of commerce is supposed to be obtained! from the 
Liquidamhar orieniale of Cyprus, and comes by the Red 
Sea from the Persian Gulf; but the subject requires 
investigation, for others believe the plant grows in Co- 
bross, an island of the upper end of tbe Red Sea. Pr. 
Pereira has ascertained that the liquid storax comes to us 
by way of Trieste ; the storax of the Indian A^rchipelago 
is yielded by the Liquidanthar Altiiwia of Blume, 






^ 

^ 



414 



BOTANY. 



[Sect. XIL 



by many trees and 



'< 



4i 



Adelaide Resin. — What is the source of the red resin 
from this colony of South Australia ? 

(N.B. Tlie various gums yielded 
barks affording tannin in Australia require careful in- 

vesticatiou.) 

Is the true cinnamon of Ceylon the production of one 
species, or are other kinds employed ? What occasions 
the red colour of the oil of cinnamon from Ceylon ? 

Tacamahaca of Ceylon. — Specimens obtained from 
Calophyllum Inophyllum are desirable, in order to aid 
pharmacologists in accurately determining the Tacamanaoa 

of European commerce. 

Ceylon {Long or Wild) Cardamom. — What is the 
plant so called in Ceylon, and named by Mr, Moon 
Alvinia Granum. Paradisce9 Can it be identical ^dth 
the true Gixiins of Pai^adise of the western coast of 
Africa ? 



Rice-paper of 



This has been incorrectly re- 
ferred to the vShola {j^schynomene asperafa) ; but we are 
still quite ignorant of the orisfin of this familiar and 



exquisitely delicar- substance. It is the pith of some 
plant, but wli at ? 



Africa {including Aralia and Abyssinia). 



•-^ 



Cape Aloes. — "V^^ 



particular species of Aloe 



affbrdinir the dru^ of this name ? What is the kind used 



at Bethelsdorp^ near Algoa Bay? 

Madagascar Cardamcm. — Is it Arnomum angustifo- 



linm 9 
home* 



be 



/"V • 



Fruits of Western Africa 



A full col- 



\ 



\ 



I 



\-- 



*H 



Sect. XIL] 



BOTANY* 



n *^ 






h 






« 



\^ I 



Hf^ 



1 1 



. .1 



I 



lection of these (comprismg the various kinds of carda- 
mom), the planfe, with roots and fruit, should be trans- 
mitted home, with the native names appended to them. 

Myrrh. — Is the myrrh of commerce produced by one 
vegetable species ? or several ? If by several, specimens 
of each kind and of the plant affording it are desirable, 
accompanied by the native appellations. It is particu- 
larly important to know whether the myrrh of commerce 



be the growth of Arabia or of Abyssinia and the adjacent 

parts of Africa. 

Euphorbhan Gum. — What is the species of Euphorbia 



affording the substance thus called in commerce, and 
which comes from Mogadore ? The stems foimd In the 
commercial Euphorbium are not those of the plant 
figured in Jackson's ' Morocco.' nor yet are they those of 
Euphorbia officinarum or E. Canarieiisis, 



flower 



Shea Butter. — Living plants and specimens in 
and fruit are required. 

Galam Bvttcr, — Is this identical with the Shea butter 
of Park ? 

Camwood. — The source of the dye-wood so called, 
from the Gold Coast, with specimens of the tree, are a 
desideratum. 

Biicku of the South- African Hottentots.— -To deter- 
mine the different kinds collected by the natives. 

Senna. — What plant yields the African .:>enna ? 
Richardson says it is brought from Ghat, in the Sahara. 



African Oak, or African Teak. 



This wood, though 



t? 



largely imported by our royal dock-yards from the western 
coast of Africa, is totallv unknown botanically. 

Ichaboe Resin. — The Ichaboe ships did, on more than 



\ 



> 



416 



BOTANY. 



[Sect. XII ■ 



one occaHjon, bring from ti e adjacent shores of Africa a 
gum-resinj conBtituted of the dead steips of a Geranium 
allied to, if not identical with, the South African Gera- 
ni :m spinosui^ o^ linnseus (JMonsonia Burmanni^ D, C). 
An account of this substance appeared in • Eden's 
Voyage in sea.rch for Nitre and the true nature of Guano. 
London, 1846/ None is now to be procured in England, 
and it is believed that the nature and property of this 
singular gum-resin were not examined. Perfect speci- 
mens of the gum-resin and the plant are desired. 

N.B. Much information remains to be obtained re- 
pectin 
western Africa. 



s 






the useful woods, gums, dye-stuffs, Ac, of 



America. 



SarsapariUa. — To ascertain the plants yielding the 
several sorts of commerce, especially those called Ja- 
maica Sarsaparilla (said to be the produce of the Mosquito 
lore, and to be brought to England via Jamaica), Lima 




Sarsaparilla, which comes to us from Costa Rica (can this 
be extracted from the plant which yields the Jamaica 
Sarsaparilla ?), Honduras Sarsap-^rilla, and the BraziHan 
Sarsaparilla. 

Balsam of Copaiva is imported from several parts of 
Brazil : it varies somewhat in properties, and is con- 
sidered to be the produce of several species of the genus 
Covaifera, 



It is desirable to obtain the balsam of each 
>ecies, with a specimen in flower and leaf, and, if 
possible, in fruit, of the tree affording it, and the name of 
the district where the tree 
lation there. 



?rows^ and its native appel- 



/ 



Sect. XII.] 



BOTANY. 



417 



1^ 



h^ 



*!. 



r 



m 



Balsam of Tolu and Balsam of P 



It may be said 



of these balsa^ns, as of tbe Storax and Liquidamhay^ of tii 



a 



EaBt. that much confusion exists with regard to the 



^'9 



substances so called, the same name being applied in 



i^v.v.o, and different 



respectiyely 



ferent places to different substances 
names to the same substance. The ti 
yielding^ the countries producing, the mode of obtaining, 
ihiQ native names and the local ones of these article 



2 



should be carefully sought and ascertained : samples of 
the products must accompany the specimens of the trees. 

YellotV'Bm'k^ Royal Yelloiv-Bark or Calisaya^ the 
produce of La Paz, requires to be identified with the tree 
which yields it. Specimens of the tree in fruit, in flower, 
and leaf, of the stems with the bark on and the bark 



removed, should be sent along with the description- 



Ipccacuan, Fahe.—'Yvom. Brazil (the native country 
also of the true Ipecacuan, Cephaelis Ipecacvmilia) a 
"false ipecacuan " is derived. What plant produces the 
latter? What is its native name, and may it not be 
equally valuable with the true ? 

Cascarilla Bark. — It is important to trace the cascarilla 
bark of English commerce (from Jamaica, or the Ba- 
hamas ?) and that of Continental commerce (probably of 
Vera Cruz) to their true source. Are they derived from 
a species of Croton ? and what particular kind ? 

Coca of Peru, — Ascertain the facts as to the con- 
sumption and effects of this substance (the foliage of 
Ervthroxvlon Coca : see a loi 




Botanical Mag. 



account in the Companion 



). A quantity would b 

mniation, not less than son 



e 



interesting for 



T 3 






t 

i 



418 



BOX AK Y. 



[Sect. XII. 













i 





Quassia,— Why is Sur'mam Quassia superseded by 
that from Jamaica ? A comparative examination of the 
two barks cheiuically is required. 

Angostura Bark. — To trace the different sorts to their 
true sources in Orinoco. 

Tons les Mais -—A, nutritive fecula, prepared at St. 



Kitts. From what species of Canna is it derived ? 

Contraycrva. — Is the Brazilian article yielded solely 
by Dorsteiiia Contrayerva, or by other species too ? 

Cojjaiva. — To determine what species of plants afford 
the best and worst kinds respectively in Brazil. 

To trace accurately the true kinds to the 



Cinchona. 



trees seen to produce the barks in Peru. 



False Cinchonas. — To obtain authentic samples of Qiiiu' 
quina Colorada of Brazil, St. Lucia bark of Mexico, and 

Piavi bark (of Brazil). 

Cevadilla, — To determine whether the Helonias officii 



4-1, 



e 



nalis or Veratrum SahadiUa^ both Mexican plants, is 
best adapted for the preparation of Veratrine. 

Cohoon Oil. — The source is unknown of this solid oil, 
which resembles that from the cocoa-nut : it is said to be 



( 



B 



Aloe.—Whzi 




alFords the drug thus 
called ? Is it not a plant imported from Africa ? No 
true Aloe appears to be an original native of the New 
World, any more than a true Cactus is aboriginal of the 
Old World. 

Many gums paid drugs are said, in ' Edwards's Voyage 



up 



the Amazon River,' to be exported from Para in 
f>ra;sil Whitlier are they sent ? Whtxt are they ? And 
what are the plants which yield them ? 



I 

J 



'• 



I 

\ 



^ * 




• * 1 ■! 



• ' 



J 



■ 1 



Sect XII.] 



BC)T4.N1. 



419 



By this list of Inquircnda it will be seen that they prin- 
cipally refer to the productions of warm and dry climates, 
where indeed the most valuable vegetable substances are 
foimd. Temperate regions, however, afford ample scope 
for the researches of an intelligent naturalist. In every 
country, too, certain localities offer peculiar facilities for 
tracing the articles of commerce to their soin^ces= Such 
are the capitals and principal sea-ports : Rio Janeiro, for 
example, for the products of Brazil ; Senegambia for the 
interior of North- Western Africa : and Smyrna for Asia 
Minor. The rich products of Eastern India find their 
way to Ein-ope by various channels, especially Calcutta 
and Ceylon ; those of North- Western India, some by tlie 
Levant or Trieste, .but much the greater quantity by 
Aden, Mocha, and, above all. 



M 



The latter 



places are also frequently the outlets for the productions 
of Persia, Arabia, iVbyssinia, and the east coast of Africa. 
Again, at Kurrachee, and probably better at Hyderabad, 
Dr. Boyle states that a detailed list of the articles brought 
down that river, and which are highly important to he 
ascertained, may probably be had. Travellers, who visit 
the localities where any interesting vegetable substances 
abound, will confer a great service upon science by pro- 
curing not only these articles, but the identical plants 
from which they see them collected. And it is 




to do this, even in the case of common and well-known 
productions, for many of them need to be verified, and 



to have the opinion of preceding observers confirmed. It 



^^ 



is only by this means that we shall become acquainted 



Afi 



Oak 



or TeaL and with the 



various 



kinds of Cinchonas or Medicinal Barks of Peru. Of 




I.OTANY, 



[Sect. 3:11. 



f 



the plants affording the latter, we are as ignorant :.^ 
whe'^ this invaluable medicine was first introduced into 
Europe by the Jesuits in 1632, It is a frequent and 
ju^^ subject of regretj that naturalists who make collec- 
tions in remote and little frequented countries, are ap 
to neglect the procuring of authentic specimens of the 



t 



M 



Economy, 



It is difficult to recommend botanical hooks^ useful to 



an uiiiyersal traveller* and 



form 



library. Many of the best collections of plants have 
been made without books ; and, unfortunately, there is 
no complete work published, De Candolle's ' 



R 



Candolle's ' Prodromus 
abilts ' is the best, and 

it is advancing towards a termination ; and Walpers* 

^ Repertorhtm 




SysternaticcB ^ is a valuable 
supplement to It. Don's * Dictionary of Gardening and 
Botany ' is useful, so far as it goes : it is in 4 vols., 
4to., published at 14/. 8.^, but now offered by many 
booksellers at 1/. 8=s'. 



f 



Dr. Lindlev's various intro- 



ductory w^orks on Botany ought to be in the hand of 
every student, and, above all, his * Vegetable Kingdom.^ 
• Loudon's Encyclopcedia of Plants^^ with its numerous 
wood-cuts, is an excellent travelling companion. And 
for any particular country it is desirable to ascertain 



the books that may happen to describe the vegetation 
of it. They are too numerous to allow of a list bein 
here given, 




•\ 



4 



\ 






-^ ■,— 



IT 



App.J 



BOTANY. 



421 



k 



APPENDIX. 



»» 




t 



I f 






H 



/ 



c 



Extract of a Letter to Capt. W. A. B. Hamilton^ R.N., Secretary to the 
Admiralty, on the collection of information respecting Foreign Timber 
useful for Naval and oth.r purposes, from A. P, B. Creuze, Esq. 
(Principal Surveyor at Lloyd's)? dated Lloyd's, 2, White Lion Court, 
26th January, 1848- 

A GOOD accountof the timber-produce of the world, or at least of our own 
possessions, is greatly wanted. Timber for masting and ship-buiidin 
purposes is annually becoming more scarce. In proof of this r~ ertion, 
compare the ease with which large topmasts could be got at tlie tir: . of my 
early service in Her Majesty's Yards, say 25 to 35 years ago, with the 
present difficulty; or, compare the pr— nt su])ply of trees, which will 
onvert for main pieces of rudder, stern-posts, stems, floors, second 
futtocks, &c. of large ships, with that of those years. I might multiply 
instances, but these will suffice in illustration. 

The " Memorandum " should, I submit, call the attention of naval 
officers, especially those of surveying ships^ to the timber of every 
country which they visit They should be instructed that whenever 
they meet with timber which they consider availabh-^ for the naval 
service, or generally for ship-building purposes, they are to procure 
information upon it; to the nature of which information the followin 
heads may serve as some guide : 

The average contents per tree, obtained by measuring, say ten trees 
which have apparently attained the perfection of their gro¥. ili, that is, 
are of the average size, without evident decay in the trunk or main 
limbs, and of which the foliage exhibits in every part equal freshness. 
The method of measuring may be obtained from a book called * Hoppiis's 
Mea.^.rcr/ 

The average distance from the ground to the lowest branch. 

The diameter of the trunk below and clear of the insertion of this 
brancli, and the diameter above and clear of the swell of the roots, 

A rough sketch of the growth of the main stem, and of ten or twelve 
feet in length of the principal limbs. The example selected for the 
sketch should be the tree which will give the best idea of the gein^ I 
growth of the tim^-er. 

A specimen of the flower and of the foliage. The first may be pre- 
served by placing it, stem downwards, in a jar partially filled with dry 

sand (not from ialt water, unless, previously to^ being dried, it has been 



6 




- ♦-a -fj 



422 



BOTANY. 



[App. 



thoroughly cleansed from salt), and then gently filling up the jar ^a^ith 
firie'dried sand till the specimen is completely coTored ; the foliage may 
l>e placed between the leaves of a hiotting-book. 

The fruu, or seed-vessel, which may be preserved according to its 

nature. 

A section from the truuk of a tree, say six inches in thickness (like a 

cheese), with the bark and all perfect. 

If posdble the specific gravity or weight of a very exactly cut cubic 
foot of the verfect wood of the tree taken from the butt end, and of 
another cubic foot taken from the top end of the trunk, when first fcUed ; 
these weights marked upon the specimens, and the specimens brought 
home to be again weighed and measured when seasoned. 

The uaiure of the soil in which the trees apparently flourish most, 
and whether the weeds, so far as can be a;^ ^ . . tained^ are such as grow 

in moist or dry localities. 

General observations as to the appearance of the decay in any trees 
of the species which may have fallen, and may be lying about de- 
caying ; also, if the country be inhabited, the local uses to which the 
timber is put, and the state of any of it which can be ascertained to have 
been in Ions use for any purpose which is in its nature trying to the 



durability of timber, as alternations of exposure to wet and dry. 

Observations as to the probable ^■^ppH-, and of the facilities or other- 
wise afforded by the nature of the country for conveying the logs to 

water-carriage. 

A knowledge of the particulars required under these heads would 

enable a correct judgment to be formed of the nature of the timber, and 
of the purposes for which it might be available, and therefore, whether 
it would be advantageous to ' port any for Her Majesty's service. 



I am, my dear Sir, 



Yours very sincerely 



9 



AuGiTSTiN F. B. Crecze. 






-i 



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X 




) 



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4 






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^f'l# 




>1 



Section XIII. 



ETHNOLOGY 





f 

r 



<- 



■> 



, /^---r> 



4 



r|t 



Br the late J. C. PRICHAEDj Esq., M.D. 

There are few subjects that can engage the attention of 

intelligent travellers, more worthy of interest, or on which 

any additions to our previous stock of information will be 

more generally appreciated, than ethnology. Under that 
term is comprised all that relates to hunian behigs, 

whether regarded as individuals or as members of families 



to 



or communities. The former head includeis the physical 
history of man ; that is, an account of the peculiarities of 
his bodily form and constitution^ as they arc displayed 
in difierent tribes, and under different circumstance? of 
climate, local situation. 



clothing, nutrition, and 



under 






he various conditions which are supposed to 



occasion 



diversities of organic development. The same expression 
may also, in a wide sense, comprehend all observations 
tending to illustrate psychology, or the history of the 
intellectual and moral faculties, the sentiments, feelings. 
acquired habits, and natural propensities. To the second 
division of tulo general subject, viz., to the history of man 
as a social being, must be referred all observations as to 
the progress of men in arts and civilization in different 



counti 



■civil and 



\ 

I 



^5 



u 



i 




t 






ETHNOLOGY. 



[Sect. XIIL 



relif^-iouSj their acquirements and traditions, literature* 
poetry, music, agriculture, trade and commerce, naviga- 
tion ; and, whicli of all things affords the most important 
aids in all researches as to the origin and affinities of 
different tribes or races, their languages and dialects. 



On almost every topic now enumerated our acquaint- 
ance with remote nations is at present much more exten- 
sive than it was a quarter of a century ago ; but on all it 
is still very defective. We shall touch upon tlie different 
subjects of tliiB investigation in a very brief manner, with 
a view to point out what remains to be done in each 
particular, and to offer some suggestions as to the best 
method of proceeding. 



!• Of the Physical Chaixicters of Nations. 

The physical description of any tribe or race must 

striking and 



more s 



commence with an account of the 

obvious characteristics of complexion, features, figure, and 

stature. 

In reference to the complexion or colour, it is not 
enough to know generally whether it is black or white, 
or brown. The exact shade of colour should be described 
as it prevails in the majority of persons in any tribe, and 
all the variations should be noted which occur in indi- 
viduals. If a great difference of colour shoxdd be 
observed in the people of the same communit}, care 
should be taken, by repeated inquiries, to ascertain, it 

whether such diversities are merely accidental 



possible 



varieties, or are connected with any distinction of tribe or 



caste. 



In many countries tribes exist who, while they 
preserve their ^tock distinct, by avoiding intermarnag . 



I'. 



i 






( 






T 

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i 
r 



? 



»*y. 



) 



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MSt 



1 



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t ? 



V 

A 



it 



-i 



r 



Sect. XIIL] 



BTHNOLOGY* 



425 



continue to differ from each other in colour and other 
particulars, though in other instances great varieties are 
ohserved within the limits of the same race, which appear 



•ft' 



as if they were capricious and accidental deviations, 
analogous to those varieties which appear in cattle and 
other domestic animals. A careful inquiry as to the 
h^'-^^ory of individuals and families will sometimes deter- 
mine how far the phenomena alluded to may he referable 
to either of these observations. 

The shape of the features and the form and expression 
of the countenance should be described. For this pur- 
pose words afford but very imperfect means of communi- 



cating correct ideas. It will be advisable in rJl instances 



to obtain, if possible, correct portraits of persons of both 
sexes, and these should be coloured so as to represent 
the complexion as well as the form of the countenance. 
If no artist should be present who is capable of taking a 
likeness, the form of the features may at least be described 
by a profile or shaded outline. 

The colour of the eves should be noted, as well as the 
direction of the eyebrov»o^ whether oblique, as in the 
Chinese and some Tartar races, and standing upwards 
tow^ards the temples, or straight and parallel to the axes 
of the orbits, as in most European heads. 

The hair, vvhether woolly and crisp, or curled and 
wavy, or straight and flowing, should be described, and 
specimens obtained of it. Notice should be taken of any 
varieties of the hair which occur in any particular tribe, 
there being great varieties in the nature of the hair in 
some races, while in others it is nearly uniform.. It 
i3olour should also be remarked. 



!i"- 



S 



I 



f 






ETHNOLOGY. 



[Sect. XIII. 



An account should be taken of the average stature and 
weidit in both sexes. This can onlv be obtained by the 
actual measurement and weighing of a considerable num- 
ber of iudividualsj and the number and extent of the 
measurements vshould be mentioned. The proportional 
stature of the different sexes differing in different race3. 



^ 



V 






an account should be taken of this fact. Extreme cases 
should be noticed. 

The proportion between the length of the limbs and 
the sternum, and the height of the body and the breadth 
of the pelvis, should, be ascertained, and the length of 
the fore-arm in proportion to the stature of the body. 
This is known to be much greater in some races than in 

others. 

Particular attention should be paid to the shape and 
relative size of the head, since this forms one of the 
principal characters distinguishing the several tribes of 
the human family from each other. The most authentic 
testimony in regard to this particularj and one which will 
be very a-cceptable to scientifiu men in this country, will 
be aftbrded by bringing home a collection of skulls, if 
they can be procured. In that case it would be necessary 
to select those skulls for specimens which afford the best 



idea *, 



of th" prevailing form of the head in the particular 
tribe; and if several forms are ob::rved in any race of 
people, which is the case in some islands of the Pacific 
Ocean, specimens should be sought which serve to identify 
every leading variety. If skulls cannot be procured, the 
best substitute \vili be casts of heads. Failing these, it 



will be requisite to take measurements. Such measure- 
ments should state the proportion between the longitudinal 



I 



f 



) 






I 



--"<ii 







Sect. XIIL] 



ETHNOLOay. 



427 



*4 






^ 



» 

L 



1^1 (Ut ^ ' f 



1 



au; 



1 , 



and transverse diameters of the skull, wliich will show 



whether the skulls of the tribe belong to the elongated 



form or to a rounder one. The facial angle may also be 
taken, formed by two lines, one of which falls from the 
forehead slanting over the edge of the upper jaw-bone, 
and the other passing from the meatus auditorius to the 
basis of the nose. The breadth of the face should also be 



the zygomatic 



taken by measuring the space between 
arches. In well-formed heads of the European type, the 
lateral surfaces of the zygomatic '^rches lire parallel to 
the temples or the lateral surface of the frontal bone ; so 
that the breadth of the forehead above the eyes is equal 
to the breadth of the face from cheek-bone to cheek-bone, 
measured by a line passing across the bridge of the nose. 
But in the Turanian type, common to the Chinese, Mon- 
golians, and other nations of High Asia, the forehead is 



so much more narrow than the face as to give the upper 



part of the head almost a pyramidal form. An account 
should be taken of these characteristics, w^iich most obvl« 
ously distinguish the High Asiatic from the European 
type, and likewise of the extent of the upper and lov/er 
jawn, an excess of which is the chief peculiarity in the 
head of the Negro, and of other races approaching the 



Negro type. The oval, pyramidal, and prognathous 
types, as above described, constitute the three leading 
varieties in the form of the human head, but. 



together 



with the description of these characters, notice should be 
token of every peculiarity that can be detected on a care- 
ful inspection of the cranium, or of the 'leads of living 
persons, when skulls cannot be obtained. 

Observations on the form and structure of the body 



•j* 






\ 






I 






1 
* 



428 



ETHXOLOG 



J. 4 



[Sect. XIII. 



should be followed by inquiries which belong to the 



department of physiology, which includes all that relates 
to the functions of life. Under this head we must mention 
inquiries respecting the senses or sensorial faculties. It 
is well known that there are differences between the dif- 
ferent tribes of men in regard to tlie perfection of these 
facultieSj and tliat some of the nomadic nations of Higli 
Asia^ for example^ have a remarkably acute siglit and 
liearing. while other nations are equally noted for the 
perfection of taste and smelL Observations on these par- 
ticulars belong to the pliysical character of each tribe. 

Attempts should likewise be made to obtain informa- 
tion as to the relative degrees of muscular strength in 
Yarious races. An instrument invented for this purpose 
has been termed the dynamometer. If it should not be 
at hand, the same purpose may be answered by experi- 
ments show'^g what weights a given number of men can 
raise by their individual efforts. 

. Other physiological characteristics should be investi- 
gated when opportunity can be found of obtaining infor- 
mation thrtt may be satisfactory respecting them : ^uch 
are the average length of life in any tribe ; the ages of 
puberty and of the ce&bation of child-bearing, and all 
other facts connected with the animal economy, such as 



tf ' 



the number of children in families. Various questions 
have been raised by physiologists as to the phenomena 
corrnected with the functions of the female, whether they 
are subject to simila.r laws in the different races of human 
beings ; and although, generally speakhig, the result of 
such inquiries has been to show that no important dif- 
ference exists^ it is still right to pursue the inquiry in 



t 



f 



\ 



i 



^, 



f 



\. 



Sect. XIII.] 



ETHNOLOGY. 



429 



I 



(} 



1 



1 ' 



1 1 r 



:^ 



I 



\ i 



'h 



\- 



\ 






I 



i 



. I 



regard to newly discoverefl tribes, wheneyer opportunity 
is afforded by the accidental rc~^dence of medical persons 
in any place, or other contingent causes may promise to 
afford accurate results. 

Pathological observations are nearly connected with 
physiology. It behoves the traveller to collect whatever 
information he can acquire as to the diseases prevalent in 
any tribe of people, or among the inhabitants of any 
country which it is his fortune to explore. 



Q 



II. Characteristics of the State of Society^ ^-e. 

lestions which have regard to men in their social 
state, or as members of tribes or communities, take a 
much wider scope thcUi the personal history of individuals. 
The ordinary habits of life and the modes of obtainin 
subsistence are the first topics that present themselves 
when we proceed to this branch of the subject. The 
rudest or most simple 



± 







of human society is not 



without its appropriate arts. Some of these indicate as 



much cnterp 



^te 



great activity of 



the intellectual faculties, as the practices of more civilized 
men. People who subsist on the spontaneous fruits of 
the earth, without pasture of cattle or cultivation of the 
soil, must exercise great ability in merely obtaining the 
means of subsistence. This is called the hunting state. 
It is not always a primitive condition of men. The history 
of the South African nations proves that tribes of people 
may sink into it from a higher state. The Bushmen once 
resembled the pastoral Hottentots : and even the African 



bushmen, as well as the Australian savaees and the most 




destitute of the Esquimaux and other Am-crican tribes 



430 



ETHNOLOOYe 



[Sect. xiir. 






! 



i 



,> 



display as niucli ingenuity in follomng their respective 



pursuits as nations of much more refined and artificial 
habits of life. The arts and customs of natio"-^ in this 
state form an interesting chapter in the history of man- 
kind, and in the ctb^nography of particular branches of 
the human famuy. 

Races inhabiting high steppes and open plains, such as 
Great Tartary and the plateau of Southern Africa, are 
crenerally nomadic herdsmen. Their habits of life are 
very different from those of the hunting tribes, and many 



of them diifer from the latter in physical organization. 
The pastoral nations, wandering through open plains and 



enjoying a life of leisure and contemplation, have culti- 
vated astronomy and a simple kind of poetry. Their 
history presents features of great interest to those who 
have opportunities of observing them. 



Some of the rude and hunting nations have practised 
agriculture to a limited extent, but this pursuit is pre- 
cluded by the locomotive habits of the nomadic nations. 
The indolence of savages generally throws this labour, 
as is well known, on the females of the tribe. In this 
state of things hunting continues to be the main occupa- 
tion, and the habits of the trilie are not greatly changed 
by the introduction of a scanty tillage. But when the 
cultivation of the soil becomes the chief means of sub- 
sistence, the people must cease to be hunters or wandering 
herdsmen ; they become fixed on particular spots, and 
separated into small communities. Hence agricultural 
tribes differ from each other in language, and likewise in 
pliysieal characters, more than the nomadic races;. It is 
highly desirable to inquire in every country into the facts 



I 



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i 



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Sect. XIII.] 



ETHNOLOGY. 



m 



^ 



connected with this transition^ and to observe how far the 
introduction of agri cultural habits has he^^n connected 
with agrestic slavery. The change from the free and 
'vvandering life of pastoral nomades to the toilsome 
drudgery of the agriculturist k so great a change, that 
it has probably never taken place except under circum- 
stances of peculiar kind. The earliest agriculture of 
most' countries appears to have been connected w'% 
lavery. In many places there were ' 






t- 



s 



adstri 



^ 



who performed the laborious part. In many instant -^ 
these were a conquered people reduced to the 



^ondiC 



of serfs. Such were the Sudras of Luiiaj conquered by 
the twice-born classes. The Helots of the Spartans and 
perhaps the y^copyoi of the Egyptians were the descend- 



so il is 



ants of captives. In every country where the 
cultivated, as it often is, by a particular tribe, it will be 
advisable to make accurate inquiries into the history of 



such races. In these the traveller will often find the de- 
scendants of aboriginal inhabitants, the genuine peop 



of the land, and among* them he will discover th 






1 



ncient 



and primitive language of the country, while the lords 
or feudal masters of the soil, the dominant people, wall 



5 






country. 

The methods of agriculture anywhere practised should 
be noted as well as the kinds of errain w^hich are found to 



be in use. The vvhole of the esculent plants u^ed by any 
tribe of people should be described. Few races of men, 
however rude and insulated from the rest of mankind, 
have been found without some exotic vegetables. It has 
been observed that there is scarcely a hamlet in the most 



y 



432 



KTHNOLOGY, 



[Sect. XIII 



inclement parts of Lapland ^here some garden-plant may 
not Ic discov^ered whicli has been imported from places of 



more genial cJimate. Tlie esculent plants in the posi- 
session of any remote and secluded people may often 
afford a clue as to the origin and family relations of the 
tribe. 

Light also has been tlirown on this subject by the kinds 
^^^'~'"^ -tiuments used in agricultural works. Noti 



'O 






.,1 



r 

be taken of the forms of the plough and of the different 
instnaiient.^ used in tillage, and of the pecuHar methods 
of culthaticu anywhere found to be in use. 

The L....Lanical arts practised by various nations are 
to be carefully observed, such as their preparation of 



clothing, their architecture, or the manner in which they 



construct their dwellings and their household furnitu... 

A subject v/orthy of particular inquiry is their metallurgy, 
and the degrees of skill displayed m the arts of mining 
and making metallic im.plements. Many rude nations 
are known to haye had some knowledge of the precious 
metals, of gold and silver, and even to iiave smelted 
copper long before they learned to know the use uf iron. 



Vari' 
tomb 




/**^ 



01 



old are found in the 
ho were far too rude 




-^ 



to invent the manufacture of steel, and who never du 
the iron ore which abounded in their own mountains. 
The western nations of Europe are supposed to have 
made hatchets and celts and swords of copper, long before 



th 



ey maae a sim 



1 ^ *"» i = 






use of iron. In most countries we 



trace the remains of a barbarous ai^e, when cutting^ im- 
plements of various kinds were made of flint or stone, and 
when even ornaments were manufactured from bone, or 






Se 



at 

T 



a 

be 
cc 



se 



as 

G 

m 
trj 
po 

Sc 



as 
th 
sa 
or 
th 
ta^ 
of 
cl. 



3 



res 

bel 

or 



Th 



p 






■•t 



ft 




o 




I 



I 



f 



* ' 



V 



I 






* 



I 



f 



f 



^t. 






\ 
h 



f 



1 



^ 



r^ 



r I 



Sect. XI n. J 



ETHNOLOGY. 



4 






amber, or ivory, before the use of metals was discovered. 
The names given to metals should be noted, since these 
names will often afford a clue as to the countries from 
which they were imported.^ 

The art of war, as practised by various nations, affords 
a wide field of observation. The weapons used^ whether 
bows and arrows, spears, or clubs, or swords, are often 



common to scattered tribes of the same kindred, and wi] 



1 



Bush 



serve to identify nations, or at least to suggest inquiries 
as to the probability of their relationship. The ancient 
Gauls were known by their gsesa or javelins, the Ger- 
mans by their saga or military cassocks, and the Aus- 
tralians by their woomerangs or thro wing-sticks, and the 

aen are noted among the 
South African nations. 

The sort of clothing used by simple nations, as well 
as that of the more cultivated, should be described — v/he« 
ther made of the skins of animals, as among the most 
savage nations, and especially those of arctic countries, 
or of cloth prepared by weaving, or otherwise preparing 




as 



6 



table productions. Attention should be paid to the modes 
of cultivating such plants as contribute the material of 
clothing.t 



* Thus It has been observed, that the Greek name for tin, ' Kaa-a-ir^poy,' 
resembles the Indian (Sanscrit) name Kast^hered of the same metal, 
and it has been inferred that tin was first brciight to Europe from India 
before the British mines were explored. The tin-mines of Tama-Malaga^ 
or Malucca, were celebrated at a ^ery early period. 

t A curious mistake was made by the ancients in regard to silk. 
They imagined that it was prepared from beautiful flowers. 



For clothes the barbarous tribes of Seres use 

■ 

Nor oxen hides^ nor wool of fatted ewes ; 



U 



They 



( 



) 



434 



ETHNOLO«"-Y, 



[Sect. xm. 



-^ 



In everv newly discovered country It will be an in- 

ml ^ 

terestirij; subject of inquiry, what domesticated animals 
are in the possession of the natives — who., they obtained 
such as they are found to possess — whether they are 
known as wild animals of the same region, or were brought 

from some foreign land. 

Inquiry should be made as to the art of navigation 



practised by different" races. 



Some nations appear to 



have a greater aptitude for maritime pursuits than others. 
The Polynesians in some places are almost amphibious, 
while the American natives and the Australians rarely 

Several South American nations 



venture upon the sea 



are, however, expert navigators hi their inland lakes and 



vast rivers. 

The crude notions entertained by uncivilized nations 

on subjects within the scope of physical science are mat- 
ters worthy of inquiry. Science they can be hardly said 
to possess, though this was scarcely true with the ancient 
Mexicans. All nations observe the changes of the moon, 
and mep=ure the lapse of time v^ith a greater or less 
degree of accuracy by the movements of some of the 
heavenly bodies. Inquiry should be made whether the 
motions of the planets are observed, and whether their 
bodies are distinguished from fixed stars, whether attempts 
are made to ascertain the duration of the solar year, and 
whether there are names for the constellations, and what 
thev are if thcv exist* 



L 



Thev weave sweet flow'rets of the desert earth, 
Of finest texture and of richest worth- 
Robes bright of hue as flowers which deck the mead, 

Of finer texture than the spider's thread/ 

Dionys, Perieg. 755. 



i 



J 
\ 



I 



\ 



\ 



\ 



\ 



_'■': 



i . 



Sect XIII.l 



ETHNOLOGY. 



4^ 



o 





■ \ 



^ 

» 



18 



8P- 



t. 



t 

I f 







t»t 



y'\:m 



fi-V*" 



» 



r + 






ii '^^ 






r 



.» 



ii' 






h. 






^ 



u^ 



In every nation, however barbarous, it is probable that 
some sort of moralltv exists in the sentiments of men 
some notions of right and wrong —and that some practices 
are considered lawful and praiseworthy, while others are 
forbidden. The same religious impressions and the same 

r 

superstitions prevail through all the branches of a widely 
spread race, as the superstition of the tabu among the 

Inquiry should be made as to all traits of 
this description, and all the phenomena which enter into 
the psychological character of a particular tribe. Among 
these traits are the regulations respecting marriages 



Polynesians. 



in different communities^ In som.e countries a compli- 
cated, and, as it appears, a very elaborate and artificial 
system of rules prevails, founded on the intention of 
preventing intorraarriages between families even remotely 
connected by consanguinity. The institution of the Totem^ 
as it was termed among the North American nations, has 



its counterpart among the nations of Australia. Whether 
the existence of customs so similar among these widely- 
separated races is a result of former intercourse, or a 
merely accidental coincidence, it is unnecessary to inquire. 
In both countries it constitutes a remarkable trait in the 
social and moral character of the nations among whom it 
prevails, and it may lead us to believe that nations appa- 



rently the most savage and destitute are not alwa^' 



^s 




overned merely by accidental impulses and merely ani- 
mal passions, but are capable of deep thoughts and re- 
wise and well- 



flection, and of enacting ia\\ 



witn a 



understood import. 

Inquiries should be made as to 



a 



gul 



social life, not only among civilized nations ard those who 



u 2 



m 



■^ 



J 



436 



ETHNOLOGY 



[Sect. XIII. 



are possessed of tlie external appearances of civilization, 
wealth, and conveniences, but likewise among people 
less prosperous in their condition, and having the aspect 

of barbarism. 



here polygam;/ prevails, it should be ascertained, if 



W 




possible, whether there is any real disproportion in the 
numbers of the sexes. This should, indeed, be a subject 
of inquiry in every tribe wliere statistical information can 
be procured, as a matter connected with the physical 

of the people ; but it has a particular relation to 

the prevalence of polygamy. 

The mode of civil government should everywhere be a 
subject of inquiry. The more simple nations are often 
without any common and central government, and are in 

the 

when they select for some temporary enterprise as their 

chieftain some individual whose fame and prowess inspire 



appointing a leader in time of war, 



them with confidence in his guidance. 



Some nations 



have been entirely without 



the idea of combining for 



mutual aid, and the Finnish races are said to have been 
conquered by the Germanic nations piecemeal, one family 



after another falling under the yoke, till all were sub- 



dued. The Polynesian nations have princes or chieftains, 
accordins to some well-understood laws. We are not 
yet acquainted with the social institutions of the Papuas, 
if they have any such among them, which is probable. 
It is very desira ble that the fact should be ascertained by 

inqui ry . 

The religious impressions and the superstitious practices 
of every tribe of men should be carefully investigated, 



as forming a remarkable part of the history of the par- 



) 



I 






\ 



^ 



Vl-Ml 



■ + 




t«. 



J f . ' ^ 



1 Uii 



i 



I' 



t ^ 



q 




E,- 




i 


V 

r 
1 


+ 


^ 




4 

F 

L 


m 


1 




1 

r 






r 


u 


r 


b 
1 ' 



- 1 



V. 



^ 



^ 



/r . 




4- 



I 



Sect. XIII.] 



ETHNOLOGY. 



437 



ticuiar people, and an itCiU in the psychological history' of 
mankind. It is probable that no human race is destitute 
of some belief, more or less explicit or obscure, in the 



existence of supernatural powers, good and evil, and like 
wise of a future and invisible state. 



But there are 



nations who scarcely recognise in the invisible bein^ 



» 



any 



thing like will or power to punish the guilty or reward 



the good, and who do not suppose the future state to be 
a scene of retribution. This is the account which mis- 
sionaries and other persons have given of the Polynesian 



superstitious. 

The adoration of rude nations is generally directed 
towards visible objects. From this rem.ark we must 
except most of the American nations, who are said to 
believe in the existence of a spiritual ruler of the uni- 
verse. By one class of rude nations the lieavenly bodies 
are worshipped,. and the Polynesians connect this super- 

r 

stition with a mythology which is poetical and not devoid 
of ingenuity. Others, like the African nations, worship 
fetiches, or visible objects, in which they suppose some 
magical or supernatural power to be concealed, capable 



of exercising an influence on their destiny and of ensuring 
success in any undertaking— a superstition of which traces 



are to be discovered among the vulgar in many countries. 
In every tribe of people among whom intelligent tra- 
vellers may hereafter be thrown, it should be a subject of 
inquiry how far any of these observations may be con- 
firmed and extended by the history of their superstitious 
belief and practices, and to what division of nations they 
are by such traits associated. 



438 



ETKNOLOGY. 



[Sect. XIII. 



III. Layiguage^ Poetry, Literature. 

A no other means have contributed so much to the 
increase of ethnology, and to the ascertaining of the con- 
nexions and relationship of diffijrent nations, as a compa- 



ngn 




reat care bhoiild be taken in every 
newly discovered country, and among tribes whose history 
is not perfectly known, to collect the most correct informa- 
ion as to the language of the people. 
Among tribes of people who have any poetry or other 






literature, pains should be taken to obtain the best spe- 
cimens of composition in their languages. Manuscripts 
in their languages should be procured if it can possibly be 
done ; and it would be worth while to incur even a consi- 
derable expense rather than forego such an opportunity. 

In countries where the inhabitants have no knowledge 
of letters, it may sometimes be found that they have pre- 
served oral compositions, generally in some sort of verse, 
which they have recorded in their memory, and handed 
down from one generation to another. It would be very 



case 



specimen of any such pieces, and to select any which relate 
to the ancient and primaeval history of the people. 



T 
X 



f no literature or compositions of any kind have been 
preserved, the best things that can be done will be the 
following : 

I. To get some intelligent person to translate into the 
prevailing language some continuous composition, and to 

reatest care. Get in 
the first place the Lord's Prayer, since this same compo- 
sition has been most frequently collected already, and 



copy it from his moutli with the 




/ 



I 



I 



■^■^■t^l - 






Sect. XIII.l 



ETHNOLOG Y. 



439 



i 



F 



1 



■^ ^ 



kl 






f " 



Mif 



»w 



J 



exists in a much greater number of languagr-s tliaii any 
other* Next to tlie Lord's Prayer, which does not contain 
a sufficient quantity of words, the Go6pel of St. Luke pro» 



bably exists i^i a greater number of languages than any 



other composition. The sixth, and perhaps also the seventh 
chapter, may be selected from this GospeL A good trans- 
lation of these two chapters will enable a perK^un skilled in 

4 

philology to furnish a tolerably complete analysis of almost 
any language. 

IL A vocabulary should also be taken down from the 
mouths of intelJigent natives. Care should be taken to 
compare the words given by one person with the testimony 
of others, in order to correct any defect or peculiarity of 

t 

pronunciation. 

It is very important to select properly the classes of 
words. The following should be chosen : — 

L The numeral up to a hundred or more* Ascertain 
how far the people of eacli tribe can reckon. 



2. 




denoting family relations, such as lather, 



njother, brother, sister, &c. 

3. Names of the difierent parts of the body,— head 
arm, foot, Sr\ 

lies of visible natural objects, elements, &c.,— - 



4, Na 



sun, moon, fire, water, &c. 

5. Names of aniTnRls. aj; 






6. Verbs expressive of universal bodily acts, such as 



eat, drink 



hear, &c. 



7. Personal pronouns,™!, thou, he 



? 



&c. 



Prepositions, — in, from 



obtained. 



, to. &c. — if they can be 



% 
» 



\ 



440 



ETHNOLOe^Y. 



rSect XIIL 



III. It would be useful, Iii the third place, to observe 
some of the grammatical rules of the language, if oppor- 



tunity exists of becoming acquainted with tliem ; though 
if anv composition of some length shall have been obtained, 
the grammatical analysis may be furnished afterwards. 



It will not, however, be amiss to make the following 



observations 



5 



One great feature in the gramni 



ferent lansruages, which distinguishes several classes of 




lansruasres from each other, is the peculiar position given 




'^ 



auxiliarv 



auxil 



iDeant such w^ords as have no proper meaning of their 
own. but tend to explain the relation of nouns and verbs. 
Such are prepositions in our language, — upon, in, through, 
&c. It should be observed what position such words hold 
witli relation to nouns. It is a character of one great 
class of languages— viz., the Tartar dialect, or the lan- 
guages of High Asia — to place ail such particles at the 
end of nouns : thus prepositions become postpositions. In 

as yet known, particles are placed 
at the beginnings of words ; and that is the case not only 
with prepC'sition.s, but with particles of all kinds, such as 

srular into tl 




o 



plural number, 
BB Anakosah becomes the plural of Kosah. Again, in the 



American language, particles are as it were swallowed up by 

the principal words, or are inserted in the middle of them. 

It may be right to observe also whether languages 

admit the composition of words making compound epithets 



by amalgam.ating two or more simple words 



Observe also whether the words, such as names of objects, 
are monosyllables, or consist of several syllables. 



L 

V 



J 



/ 



-^-^k 



■•'-t. 



I 






It 



■•■I; 



App.] 



ETHNOLOGY 



441 



i 



A P P E N D I X. 



1 I, 
1 



n 



r r* 



r 



•'I 



• t 



^ 



V 



By THE EDITOR, 

In compiiiDg vocabularies from the mc tbs of natives, whether of written 
or unwritten languages, but especially of the latterj and of languages 
which, though reduced to writing, are so in charactei^ (like the Chinese, 
&c.) illegible to Europeans, it is of the utmost imnortaace to secure the 
possibility of a reasonably faithful repruduction of the sounds from the 
writing when read by a third party having no persoiial communication 
with either the speaker or writer. This can only, of course, be accom- 
plished by the adoption of a system of writing very different indeed from 
our ordinary English practice of spelling (which is utterly inapplicable 
to the purpose); fixing upon a set of letters, each of which shall express 
a distinct, recognised, and as arly as possible invariable sound, and 
regulating their combination by simple and fixed rules. 

Pending the introduction of a Phonetic character free from objection, 
and bearing in mind that, after all, it is only a very imperfect repre- 



sentation of the native pronunciation which can be so conveyed (although 
amply sufficient if due care be taken to render the speech of a foreigner 
intelligible among th^mi), the voyager or traveller will find ia the 
' Ethnical Alphabet' of Mr. Ellis* a stock of characters prepared to his 
hand capable of accomplishing to a considerable extent the object 
proposed;! or he may adopt the following as a conventional systeiOj 
in which only Roman, Greek, and Italic characters are employed, and 
which therefore 

ordinary printing office. In the examples annexed the letters printed 



he at once transferred from MS. into print at any 



sounds 



Vowels. 



1. u 



long (zm) as in Engl, boot; Germ. BruAer ; Ital. verd?.ra; Pr.. 

oMvrir :— short (w) as in Engl, foot ; Germ, r^nd ; lUl. bratto ; 

very short or coalescent as in Ei^!. w^ig; Germ. q?^er; Ital. 
quale. 

* * Tli^ Ethnical Alphabet, or Alphabet of Nations, tabularly arranged for the use of 
Travellers at^d Missionaries, with Examples in ten Languages.'! 

t In thus directing attention to the « Ethnical Alphabet * of Mr. Ellis for this sp. led 
purp!)se, the Editor must be understood emphatically to protest against being con- 
sidered an advocate of the "spelling reform^' of the 'Err-'' h language /or the use 
of Englishmen, as proposed and urged by cither that gentleman, Mr, Pitman, oi 
Mr. Fsulder, 

u3 



r 






1 



f 



- ^ 



— x» 



442 



o 



3. 



4. 



6. 



9. 
10. 



11. 






14. 






16, 



o 



V 






o. o 



o 



7. a 



8. a 



a 



ETHNOLOGY, 



[App- 



long (oo) as m Engl, ghost; Germ. Sch^os ; Ital. cosa; Fr. 
Qf : — short as in Engl, resolute ; Germ, hold ; Ital. dolente ; 



Fr. Napoleon. 



: — short, 



very short (v), or in Mr, Ellis's nomenclature stopped, as in 

Engl, pert, c?^t ; Germ. Versuch. 
as in Germ. Giite : Fr. Augt^ste. 
as in Germ. Lo^.e ; Fr. lenr ? counwe. 
Ions [00^ as in End. law :— short as in Engl, hot: G&rm.Gott? 

kommen, 
long (aa) as in Engl, hard 5 Germ. Haar ; Ital. andar; Fr. char :— 



.4me 



Fr. charlatan. 



long (aa) as in Engl, waft, lawgh:— short (a) as in EngL have; 



V 

quaflF, 



as in Enel. Bank, hag ; Fr. Prince ; mnsi Yin (?) 

long (aa^ as in Engl, hail ; Germ. See, stadtehen ; Ital. Ueta; Fr, 



meme, &iit :~short (a) as in Ei- J, accurate, 
long (ee) as in Engl. Heir, Hare, Hair, were; Germ. Berg, 

Starke; Ital. himiera; Fr, lumiere :— short (e) as in EngL 

men, lemon, every; Germ. l...-r, empor; Ital, eastello; Fr. 

dangereux, effort, eloigner. 
12 t as in EngL hill, bit ; Germ. gJft, gittci' ; ItaL cinque. 

as iB EngL peel, leave, believe; Germ, L^ebe; Ital. yfno; 



Fr, qui. 
as in EngL peopZe ; Germ, liefaen (pip*!, rxb»n). 



Diphtlionijs. 



J 



as in Eng, bite; Germ, beissen. 



as in EngL hvown, bot^nd^ Germ, brawn ; Fr. saoul? 



17* 

18, 









QQ 
O*-/* 



s 



N^ 



Consonants, Sfc, 
as in EngL soft; Germ, sanft; ItaL 50I0; Fr. salle. 



Germ 



19. ^h asinE--l ?^arp; Germ. ^:':^rf; ItaL lasciare ; Fr. cMen. 

20, zh as in En^l. plea.s^.re; Fr. ?ardin. 



21, th as in EngL ^Mng; Span, ^apato, nacion. 

22. dh as in EngL thixi. 



31* f, dy p, b,f. V 



m, n, L as in the English, German, Italian, and 



F 



-h 



rr as in El.^:. pray ; Germ, ^abe : ItaL rosa; rr. erreur 



r as in Enp* 



ir 






34, p or rh m in EngL Rhatuny, Rhubarb. 



Ai» 



Ui 



I 



t 



«:: 









App, ] 



ETHNOLOGY. 



443 



o5, 
36. 
37. 



as in Eugl lian^; Germ, klin^ a; Ital. lingua franca. 



i:^.-_ 



v as m i'X\ SiVish vie?j, 

y The nasal sound in Minix, D.'zieper. 



33. k as in Engl, ^ait: Gavm. i/exe; Fr. i7altel 

39. X ^s in Germ. lacAen: Span. Ximenes, reloj ; Gael, cmac.^an. 

40. y as in Germ, gelten ; Gael. Lu^^. 

Any supplemental letters maj be usedj if exactly exemijllned and 
identified, for sounds peculiar to certain languages, as the Caffer and 
Hottentot clicks, &c. 



Rules to he ohserved. 



1. 



Do not use a running hand in writing from procTinciation, but form 
each letter separately ; take care act to confound a and a. 

For capitals use tiie small characters enlarged. 

3, A vowel sound is understood to be prolo^.^ed by repeating its 

character acccrding to the analogy of the German and Dutch. If 

the sound be really r-_^ ated, as in Oolite, insert a hyphen O-o thus 

0-0, or an apostrophe O'o. If the Yowei be simply once written, it 



^ '] 



If 



expresses the shortest sound conveying the fall vowel sound, 
intended to be very short, or to have that abruptness which has 
been called the stopped sound before a consonant, double the con- 
sonant, especially if the ** stopped sound " be really perceptibly 
difterent as a true vowel sound from the -^open," which in the 
English is sometimes the case. 
4. Two different vowels coming together, when the first is intended to 
be shortened to the utmost possible degree consistent with the 
distinct audibility of its vowel character, it is to be prefixed singly 
to the other ; as in the so-called English diphthongs ol, tu foi, iuu). 



or, as in such words as i 



^j-^^ 



qu 



a 



ff 



(uett, ii, kuaft). 



But if the 



vowels are intended to be separately and distinctly pronounced, as in 
the Italian pai^ra, an apostrophe must be interposed, as pa'uura, or, 
if still more completely separated, a hyphen. 
5. h means rdways a true aspiration, except in the combinations sh^ zh, 
th, dh— for which, if any one should prefer to write J] 5, 6, and 9 

■ and with our entire 



respectively, he may do so with much ndvantc 



among other con- 



approbation. The insertion of h in its true pi- " 
sonants is a matter of much nicety, and requires an exact and dis 
criminating car. 
6. The " obscure vowel," No. 14, represented by a large unrnistakeable 
fullpoint, occurs only in such words as T>eople, lieben (Germ.), &e. 
Its nearest representative as a prolonged sound is v (in the above 
nomenclature) ; but it is a great fault to use this character, or any 
equivalent one, in cases where a realj distinguishable^ and particu- 



» 



I 

j 
I 



I 

I 



444 



ETHNOLOGY. 



[App.. 



i 



etymological 



instance 



to write 



the words Am^v^m. (Engl.)? Stufi? (Germ.), ventura (ItaL), Je (Fr.) 



ame 



(u) appropriated to the vowel sound in the English word cwt If, 
therefore, the necessity of imitating a well-educated usage require 
us to indicate (as no doubt it often does) a certain approach to this 
obscure v, it should be done by subscribing the point beneath the 
appropriate representation of the true vowel thu?^, Amerika, stuufe, 

ventuura, zhe, Benaares. 
Compound consonants, as in church, journal, may be resolved into 

their elements (tsh and dzh). 
S. Particular attcDtion should be paid to the accentuation by a single 
mark (0 ^^ ^^^^ syllable in each word where the prominent stress 
is laid in pronunciation, nor should the intonation of the voice be 
altogether neglected, though very difficult to reduce to any regular 
system of rules or signs, and rather a matter of description or 
mu5^ical notation than of alphabetic registry. 



/ 




■i 



I 



4 
K 



i 



J 



I 



4 



V 









t 






H 



?,. 



^ % 



r>^. 



i I 




}^ 



i 



I 



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( 445 ) 



Section XIV. 



MEDICINE AND MEDICAL 

STATISTICS. 



iiiitif 




^ 



4 



f " 









I 



i 



By ALEXANDER BRYSON, Esq., M.P 



the naval force employed on 



the gre 
foreifrn 



stations, that 



amongst the first things which will attract the attention of 
a medical officer, are the effects produced on the consti- 
tution hy a change of climate ; and the question of the 
necessity or non-necessity of meeting this change by an 
alteration of personal habits or modes of living ; whether 
on entering the tropics it will be prudent to continue the 
use of the same daily amount of food, to lessen its quan- 
tity, or to adopt a diet less stimulant as regards fluids, 



^ 

and more farinaceous as regards solids. Different view 
have been adopted on this subject, some of them erro 



neou; 



, others extravagant, or only feasible were the 
human body a mere m.achine ; while there is a third clas 
founded on practical experience, and which is deserving 
of the most respectful consideration. Opportunities to 
simplify and reduce these into a more intelligible form 
will not be found wanting in the naval service. 



In noting the meteoric changes which 



are likely ^ 



to 



446 



MEDICINE AND MEDICAL STATISTICS. [Sect. XIV. 



r 



affect health, there are not, it may be assumed, any great 
difficulties to be encountered as regards instrumental 
observation ; in these mathematical precision, at all events, 
is not so essential as they would be^ were the results 
aimed at depending on the truth of a series of arithme- 
tical sums. There is, nevertheless, a proper degree of 
accuracy required in the mere registration of this kind of 
formulae, as one omission may invalidate a whole set of 
observations.— 






uch for example as the geographical po- 



sition of the ship at the time the observations were made. 
With regard to the atmosphere, the principal things to 
be observed are its heat, degree of humidity, and weight. 
That the two first greatly influence health there is not any 
reason to doubt : but with regard to the tiiird, it would be 



• 3» 



hazardous to offi^^r any decided 

who have devoted much of their time and attention to the 



v> minion. Amonget men 



V 



L 



ew who consider that it has 



at least some imluence in disturbing occr ionally the equa- 
nimity of the mental functions. Thermomctrical obbcr- 



vations with the view of noticing the influence of atmos 




pherical heat on lieaith, should be made several times a 
day, in order that the minimum, medium, and maximum 
in the shade may be ascertained ; or even more frequently 
should there be a sudden rise or fall of the mercury. On 
board a ship under wcl^li^ it is hardly possibloj in conse- 
quence of the g-.^t variety of a^p. tb In v^mch she may 



arious 



m 



place Li th' instrument; the black bulwarks and ham- 
mock-cloths rapidly absorb the heat of the sun's ravs. and 
again tlirow it out by radiatT^n for a considerable time even 









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Sect. XIV.] MEDICINE AND MEDICAL STATISTICS. 



■± 



17 



after the sun has gone down. Should the instrument there- 
fore be placed, as has sometimes happened, contiguo^is 
to these, it ^^iil give an exaggerated view of the tempe- 



rature. The under surface of the deck planks also radiates 



heat 



be 



exposed to the rays of ^' o sun, consequently the ^^m- 
perature of the cabins and between the decks of a ship 
is sometimes greatly increased ; this, however, if conti- 
nuous hi apposition with the heat in the sun's rays, and 
in the shade, it would be desirable to place on record, 
and also to state the influence it may be supposed to have 
on the general health of a ship's company, w'^^:ther the 
inference drawn be of a practical or a theoretical nnture. 
In connexion with accumulated heat from these or other 
causes, it would also be proper to state the space allowed 
to each hammock : the number of hammocks berthed on 



one deck, ard in a general way t'-e dimen?^ions of the 
deck, together with the size and disposition of the scuttles, 
ports, and windsails. 



Acute inflammatory diseases and fevers have 



most 



unquestionably been induced by a current of external air 
riTshhig from thi: lower orifice of a windsail on men 
sleeping close to its exit Are we then to suppose, in the 



t r 



absence of all terrestrial miasmata, that these diseases 
are the i^oult of the sudden abstracdon of heat from the 
system? Simple immersion in the sea, or exposure to 
the external air in a state of nudity, has not, generally 
speaking, to the same extent, an equally deleterious effect- 
These, and subjects of a like nature, are well deserving 
the attention of every medical inquirer ; as there are still 
few of the doctrines respecting the origin of disease, or 



I 



448 



Tir 



EDICINE AND MEDICAL STATiSTICB. [Sect, XIV. 



the manner in whlcli the different forms of morbid action 



( 



o 



staLlished) progress^ culminate, and decline, 



that are so clearly demonstrable as could be wished. 

As a humid state of the atmosphere, particularly 
within the tropics, seems to exercise a considerable in- 



fluence over the health of Europeans, hygrometrical 
observations are not less essential than thermometrical, to 
a full investigation into the causes and nature of anv of 
those diseases usually denominated climatoriah Various 
instniments have been used for these purposes ; but those 
which denote with ordinary accuracy the state of the 
atmosphere, and are the least liable to get out of repair, 
are the best- The appearance of surrounding object 



and our ordinary sensations may be even trusted where 
there are no better means at hand. It will naturally 



occur to the observer to guard against confounding the 





moisture arising from any local cause, such as damp 



» 



decks, or the halitus from the breath of a large body of 
men confined in a small sparse, with the natural moisture 

J 

of tlie external air. Should the disparity, however, be- 
tween the latter and the air of the deck on which the 



men generally congregate and sleep 



) 



be exeat, it will be 



incumbent on him when he uses an instrument to note 
the differeiice. From these data, viewed in comiexion with 
the results of the thermometer, the nc_assity of a more 
fi-ee ventilation in all vessels of war destined to remain 



r^ 



* = ■* « 



lor 



years witiixn the humid regions of the tropics may thus 
be made apparent. 

To a dry air wc are accustomed to attribute a bracing 
effect, to a moist air a relaxing ; and there seems to be 



little reason to doubt the general truth of the postulatu 



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Sect, XIV.] MEDICINE AND MEDICAL STATISTICS. 



449 



the fifst increases, and the second dimniishes the amount 
of watery fluid in the system ; the one as a general rule 
conduces to health, the other to disease. How far these 
conditions modify morbid action, it would be desirable to 



ascertain. 



That intermittent and remittent fevers are 



the peculiar product of moist localities, experience amply 
proves ; and although the subject yet requires to be more 
fully examined, facts are not wanting to lead to the sup- 



position that dysentery, and 




approaching to 



dysentery, are more frequently the result of atmospheric 
changes in certain dry localities within the tropics, than 
they are in moist localities in similar parallels of latitude. 
The relative degrees of health enjoyed in vessels differ- 
ing in the hygrometrical condition of the air between 



w \-^ 




decks, from whatever cause (exclusive of external causes) 
such differences may arise, is a subject which . has Ion 
eno'aged the attention of all classes of naval officers ; and 
although the majority are of opinion that a dry condition 
is the more healthy, still there are others practically ac- 
quainted with the subject, who do not admit that the 
difference is appreciable, or who altogether repudiate the 
idea of damp decks having anything whatever to do with 
the health of a ship's company. As these conditions 
reatly depend on the modes of cleaning the luv/er decks, 
it more especially belongs to the medical officers to watch 

w^ith vigilance, and report (but not without due and 
ample experience) the effects of dampness, whether from 
accident, stress of weather, or artificially produced, as 
well as the effects of dryness artificially maintained by 
swinging stoves or other contrivances. 




The great difference between the appearancr^ ox weu 



^ 



I 
k 



450 



MEDICINE AND MEDICAL STATISTICS. [Sect. XIY 



employed in the bread-room tind hold, aiid those who are 
freely exposed on deck, or in open boats, at all hours of 
the day, cannot escape the notice of the most superficial 
observer. It is therefore of importance to ascertain ^dic- 

the solar rays be not, to a 2;reater 



T exclr^'ion from 




c"'teiit tlian is generally believed, one reason why those 

wlio have in consequence acquired a pale waxy look 
from confineiur^nt below, are more susceptible to disea*=e, 
u.nd le^s capable of sustaining its shocks, than are those 
whosr^ blocd is enriched and strengthened by the free ex- 
posure to light, heat, and air, wdiich their different avoca- 



tions ensure. 



The force of these remarks, how^ever, wall 



be best understood by those who have had opportunities 
of Witnessing the rapid change which takes place in the 
human constitution by exposure for only a short time to 
direct rays of a tropical sun. Why, in a state 



1 .- js V' 



perfect rep* 



o^e, the blood should acq^idre a brighter 
tinge, and an increased force of circulation, are inquiries, 



tiie value of which the observant physiologist will not fail 



justl} to appreciate, neither will he fail, as often as oppor- 
tunities occur, to follow up these phenomena, should they 
terminate in cIiBeasej or unhappily produce death. 

Whether the stationary population at great elevations 
above 




sea-lcveL differ from those luujitually resident 
at the sea-]evel in rapidity of pulse and respiration, are 
questions respecting vvhich there Is stiil but little known. 
In coru.c-xion with this subject the following are the prin- 
cipal objects deservins the attention of medical or other 
travellers, particularly when opportunities occur of vis 






iiig places uf gi-eat altitude :— the number of pulsations 



of the I „,.:+. the number of respirations per minute, and 



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Sect. XIV.] MEDICINE AND MEDICAL STATISTICS, 



451 



the circiirriference of the chest at several places. Tt v. Ill 
also be necessary to note the height, age, sex. and colour 



1* 



of the person examined, and whether in a standiug or 



sitting pasture at the time of examination. 



The extent to which terrestrial miasmata may be con- 
veyed by the wind has been so variously estimated, 
that correct information on the subject would tend not 
only to the benefit of the public service, but al^o to the 
credit of the medical profession. In selecting a proper 
position for an encampment, or for the anchorage of 



vesbcls of war, the greatest discretion and judgment are 



required, particularly in those countries which abound 



lluric agencies inimical to man ; and 



althouofh it mav 



■iD 



ar 



are matters with 



which the medical officer has little to do, and although 
necessity and the exigencies of the service may render 
the selection of any spot but that which is the best suited 
in a healthy point of view inevitablcj still, dreading the 
suffering, loss of life, and the inefficiency that may accrue 




to the force from a position badly chosen, the ext 
geological features of any coast or island off which 
squadron mtiy require to be concentrated cannot fail to 
attr-^^t b'" attention. 

In connexion with terrestrial emanations, atmos 
currents, depending on local causes, together with a de- 
scription of land and sea breezes, are also subjects deeply 
interesting to all classes of men, whether employed in Her 




Majesty's naval service, or otherwise engaged in maritime 
pursuits. It is, therefore, much to be desired that the coun- 
try contiguous to any unfrequented creek or bay, or tlie 
eoibouchures of tidal rivers which are hkclv to become the 



t 



/ 



4 



52 



MEDICINE AND MEDICAL STATISTICS. [Sect. XIV 



resort of sliippingj shonld be examined, and, if found to 
contain lagoons or marshes, mapped in such a way that 
those spots which are the most exposed to the malaria 






■i 

'? 



oming from these localities may be known, and if possible 
avoided as an anchorage. The nature of the soil in the 
immediate neighbourhood, the kind and the depth of water 
in lagoons, the character, depth, and consistence of swamp, 
bog, or marsh land, the description of plants which snr~ 
round or grow from them, would greatly enhance the 
value of such information. These being the acknow- 
ledged sources of fever and ague, it wonld not escape the 
zeal of the inquirer to ascertain whether they were liable 
to irruptions from the sea, or floods from the interior; 
whether fogs arose from them, and if so, at what time of 
the day or year they were most observable ; and also 
whether they emitted noxions effluvia. It has sometimes 
occurred that officers and men employed on boat service 
have been rendered conscious of the fact, that certain 
particular spots emit noxious 
than others. 




uvia more perceptibly 



-A 



Ihe tides, by occasionally washing over or breaking 
down the banks of low alluvial lauds, and by spreading 
over the adjacent country, form extensive brackish la- 
oons and marshes, which greatly impair the sanitary 
condition of a country. I'hese circumstances, therefore, 
and their influence on health, should invariably be noticed 
under the head of topographical information. 




4?.^,Tr +T^; 



jro nre lew thmgs of more importance to the naval 
medical officer than the origin and characters of febrile 
diseases, as a knowledge of the facts connected with the 
former may greatly bias his judgment with regard to the 



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Sect. XIVJ MEDICINE AND MEDICAL STATISTICS. 



453 



latter, and as the expression of bis profes-v-rnal opini 
thus influenced or formed, particularly with regard to 
their being of an infectious or of a non-infectious cha- 
racter^ may involve not only the safety of the greater 
part of the men in his own vessel, but that of the crews 
belonging to other ships, or even of communities residing 
on shore, it will be admitted that these are not subjects, 
when opportunities occur, that ought to be superficially 
examined or inattentively reported. 

Besides endemic and epidemic diseases arising from 
general or terrestrial sources extraneous to a ship, there 
are others which originate in local or personal causes 
existing on board. To distinguish betv/een these is a 

matter of greater difficulty than seems to be generally 
apprehended. For instance, it has frequently occurred 
that fever has broken out in a single vessel of a squadron, 
and attacked not only the whole or the greater part of 
her crew, but all visitors who ventured on board, although 
they remained in her only a few hours. If these latter, 
after returning to their own ship or home, passed through 
the disease without communicating it to any other person, 
the opinion generally formed has been, that the fever was 
the result of exposure to some local cause unconnected 
with the personal emanations of the sick ; but if in either 
case the attendants or immediate neighbours of the vi- 
sitors were subsequently, that is, within two or three 
weeks, seized with fever similar to that of the latter and 
of the patients in the ship, and again other persons who 
had been in close communication with them w^ere attacked, 
then the conclusion arrived at has been (as indeed it 
could not be otherwise) that the disease, if it were iiot in 



f- 



ml 



I 



454 



MEDICINE ANI> MEDICAL STATISTICS. [Sect. XIV. 



the first mstaiice the result of personal contagion, had 
acquired in the course of its progress the power of propa- 

r 

gating itself, and that in all probability it would through 
a series of subjp^^ts retain that power for an indefinite 

Still, notwithstanding the most carefiil siftins" of 



time. 



every 




cu'cumsrance 



connected with the first cases, (it 



having been also ascertained that no disease of the same 
character had existed for several months previously in or 
near tLe locality, and that the men had not been on shore 
or absent in boats,) may render it necessary to conclude 
that it originated from some cause within the ship ; it will 
yet remain to be determined whether that was of a local or 
of a personal nature, or of some peculiar combination of 
the two, either with or without adjunctive predisposition. 
In a large majority of instances it most unquestionably 



w^ill be difficult, if not im.possible, to decide ; nevertheless, 
a concise narrative of the events as they occur should be 
committed to paper, in order that it may be made avail- 
able, should it be squired for any investigation in con- 
nexion with the reappearance of the fever at a future 
period either in the same or in a different locality. 

When a fever has broken out in a ^'■essel at sea, from a 
foul state of her holds, and. without her having anv subse- 
quent communication with the shore, continues to make 
progress, attacking man after man, how, it may be asked, 
is it possible to ascertain whether, as is sometimes the 



ca^e, it ] 






cquired a contagious character or not ? The 
space is small, and the whole of the men being equally 
exposed to the original exciting cause, and, if such have 
been generated, to the personal, are there any means of 
distinguishing the effects of the one from those of the 



^* 



Sect. XIV.] MEDICINE AND MEDICAL STATISTICS. 



45^ 



ul 



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other, with that degree of certainty which would warrant 



the medical officer i> Litis a conscientious opinion. 



if 



required by the arrival of the vessel in a port? The 
great ??inxilarity of all continued and remittent fevers, but 
more particularly of the fevers of the tropicB. from what- 
ever source they may have sprung, together with predis- 
position from fear, foti^ue. or deraneement of the diges 




tive organs^ and the utter impressibility of complete segre- 



gation, even in the most roomy vessel, will, it is appre« 
hended, render it extremely difficult to make such a 
distinction ; and the delivery of any opinion beyond that 
which may be h}7>othetically formed impracticable. Still 
experience, undoubtedly, 
greatly assist those who have had the benefit of its teach- 
ing ; hence the value to be attached to all such authenti- 
cated truthful data, and the suspicion with which imperfect, 
speculativCj or garbled accounts should be received- 
If we were dc^'red to write dov/n " what to observe 



in so critical a juncture, will 



99 



with respect to tropical fever, the subject might be ex- 
panded into a volume, or compressed into a few words ; 



for the occasion it may suffice to mention those things 
which would facilitate any inquiry for which it might be 
necessary to consult the medical retunis of the Navy. 
One of the first objects of the medical officer, when an 
irruption of fever occurs in a ship of war, wnll be to ascer- 
tain, if possible, whether it arises from causes internal or 



external to the ship ; for on this will depend the propriety 
of removing the cause, or removing from the cause, viz.. 



clearing out the vessel, or quitting the iocahty. If it 



arise from causes within the vessel, tliese should be stnt^d, 
and also the means tak^^n to remove them : if from causes 









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456 



MEDICINE ANP MEDICAL STATISTICS. [Sect. XIV. 



extraneous to the ship, tliey r^m^ if possible, should be 
described, as well as the manner in which the men were 
expo&ed to their influence. The treatment of the disease 
will naturally rivet the attention to the symptoms ; these 
again should lead to a more practically useful nosography 
than is generally adopted ; the disease being placed under 



one of the three following distinctive heads, viz., con 



tinned, remittent, or intermittent. This, however, should 
it be deemed of importance, need not prevent the annexa- 
tion of any other qualifying distinction, such as bilious, 
ardent, or yellow ; but to reconcile the conflicting opinions 
which the writings of discrepant authors have called into 
existence respecting tropical fever, proof of the absence or 
presence of remissions^ in some of its worst forms, may 
still be considered necessary. 

3 long as there is a British squadron on the sea, 
yellow-fever, as it is called, must claim a large share of 
attention ; and as it is seldom brought to these shores, he 



Ao 



who 



as an e 



encountere it on its own domain, profiting by the 
occasion, will do well, while it is under his eye, to examine 
carefully into its origin and character. "When it occurs 

pidemic its source should be looked for, its course 
traced, and its disappearance noted ; and whether yellow 
suffusion be present in all the cases, or only in part of 
them, whether, when black vomit occurs, the disease seems 



to acquire generally a greater degree of virulence, and 



whether, in consequence of such aggravation, marked by 
deep yellow suifusion, dark-coloured blood, hr^morrhage, 
and, in the fatal cases, black vomit, it has assumed contagi- 
ous properties. If the fever has commenced in a ship at sea. 



it will be in vain^ as already noticed, to attempt coming 



Sec 



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Sect. XIV.] MEDICINE AND MEDICAL STATISTICS. 



4f- 



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to any deeisioD as to llie qnestion of contagion^ until it 
■^^^s Loen commanicated to some person who had not hoen 
on board, fr^^ him to a 



Q' 



a se^ondj and perhaps from the 
oniH to a third. Second attacks of this disease should 



iTivariably be noted in the returns. 






tile treatment of yeilow-fever there is mo '^ assuredly 
much to ^/userve, and much to h^arn. The effects of the 
most vaunted reraedies should be comnnred, without 

JL 

I.^ing sight of the natural resiliency of the vital functions 
tG*..r(ls a stat" '^f health: this is a rule so essentially 

that not to apply it would vitiate the inferences. 



Hi 



F' ^od-]^^*''^^g, and tho nature of the blood abstracted. 



• • 



offer a fair field for observation^ w^hilst the empirical 
modes in wlu^' /e have been taught to exhibit mercury 
will perhap - some experience, induce the younger 

1 . c stigate the grounds on whi ch hi 

^^ ded these questionable practices, and to 

V with the results obtained in the present 

The c f the disease when quinine, the most 



•piA c>ician 



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Hay 



vaiur^ -'^ ":^' all our reraedies, should be commenced, and 

-f r ^trj^i-iit if; xnay be administered, are questions 



t 



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tlicU' ba V 



w :r 



J 



-.:t been settled. 



on 



Patholosdcai :..estigationB have thrown but 



little light 



->. £ 



sea! "■: 



.~*x 



^^mple idiopathic fever. To detect the 
^^ e, or to ascertain the cause of 



^ i_1 



solid -^ hnvt h^;*-n explored in vain : the vital organs 
hc..d. thf* t\ ^: 



reveal v\.. 
there il- :.. 



scienc 
anim.al 



J^ f^ j-S r- 



.9 






], the 

s 01 the 

^x, and the abdomen^ have each refused to 

:y g.^ve up their functions: to the fluids, 

: ^ ^'ifh. the additional appliances w^hich the 

> aifords, and with a better knowledge of 



■^^ -•- JS' -•■ ^ 



mistry, we must resort 



The blood, in con- 



X 



L 

I 



458 



MEDICINE AND MEDICAL STATISTICS. [Sect. XIV, 



i 
% 



'^TvS 



- VI- 

: 5 



^ 



nexion with respiration, will require to he examined to 
ascertain whetlicrtbe %nctional derangement which exists 



in the organs of oangnification and respiration, in the 
first instance, he the effect of a chemical change in the 
blood ; or whether it be the result of an impression made 
on t 






nervous system by some power exterior to the 
body : and w^hether such derangement of action inter- 
rupts the normal transfer of elementary principles bet\Yeen 
the external air and the blood, thereby leaving the latter 



so STeatlv altered and deteriorated as to be chemicallY 
defective in those constituents requisite for the repair of 
the organic structures, while it abounds in the lethal 
effete matters that are constantly received into it from the 
decav of the latter. 

In the Naval service, more perhaps than in any otlie^*^ 
there are frequent opportunities of ascertaining to a day. 



and even to an hour, the exact period of incubation ^n 
certain febrile and eruptive diseases: although this m '' 
also gri-atly depend on the disease being g^^dually ui 

F 

suddenly developed. A party of men, a boat's crew for 
instance, ni-y enter a vessel, a house, or a village in 
w^liich disease is raging ; or they may land, expose thoin- 
selves L the influence of a "homicidal marsh," and then 
retnri on board their own vessel, having intialed a ^uffi- 
ciencj of th^^ poison to establish a certain specific morbid 
action J bearing, if of a personal nature, the exact sirr/.'^i- 
tude of its parent ; and if of a terrestrial, that type of 
fe. ur v^LIcli is peculiar to the climate orL-^ulity, or to th< 



>Vr- 



1 O V *4.i 



■mg epidemic — it will of course follow that in pro- 



P 

p^'^tion to th 



e 



r^^^gth of time the patier^- have been 



exposed to the exciting miasm, so in an inverse d^^ree 



^ 



.^ 



• -viV 



' i t( 



W',. 



*U til,. 



ir. 



f I 



U] 



v> t^ .1 






to tl),. 



rat 



■tweei 



I! 



AU 



i; 



"! 



^1 t V' 



,. i.i 



) a ( 



J '^ 



-i.: 



:on 



1 ■ V 






L* - 






3 



o 






tt' ' 



ft* 



TPO '^^ 



I 



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tio 



or*'' 



i 



^e ' 



. j^ryi 



d^ 



t 



Sect. XIV.] MEDICINE AND MEDICAL STATISTICS. 



459 



will be the value of the mforrnation. 



as during a 



pro- 



tract" d exposure there 1^ not any means of even approxi- 
mately ascertaining when the system had acquired the 
reqrasite charge necessary to the evolutioij of the disease ; 
although the latent period of endemic and epidemic dis- 
eases is a subject ^yhich is both curious and interesting ; 
still as regards contagious diseases it is infinitely more so* 
as it is principally on a correct knowledge of these periods 



that the quarantine laws can be efficiently administered, 
With a know^'^dge of these facts it vvll] not be saying 



too much to aiBrm. that it greatly behoves the medical 



officer of the naval service to lose no opportunities of 

record a succinct history of every case of 



lacin 



piacmg on 



disease, which has been contracted 



exposi 



specific exciting cause for so short a period as will serve 
to mark the stage of incubation to a single day. There 
may by this means be such a mass of evidence brought to 
bear on the subject, as Mall greatly simplify our view^s on 
the doctrines of contagion, and at the same time dis- 
embarre^^ the 'laws of quarantine of many 



restrictive 



' formalities, that are not only useless in a sanitary point 
of view, but injurious to commerce, and personally vexa- 



tious. 



As the preceding observations are applicable more or 



le^ in a general way to other endemic, epidemic, or con 

tagio-is disease 






it will be unnecessary to go over the 




sr* u^ ground with respect to them. The incubative 
period of plague, and if it rage epidemically, proof of its 
having, independently of epidemic influence, acquired 
contagious properties which have been transmitted from 
(ine person to another, either simply through the medium 



X 2 



j^^ 



I 



1 



460 



MEDICINE AND MEDICAL STATISTICS. [Sect. XIV,. 



of the atmospiiere, or by mecus of fomites, are still 
question- of paramouBt interest to every nation wliieli lias 
commumcation with the shores of the Mediterranean. 
Vv^ith respect to malignant cholera, it would be difficult 



to say in what particu 



icti 



it is most deserving attention 



the causes essential to its production, the manner in which 
the fluids become poisoned, and the vital functions de- 
rano-ed are unfortunately about as little understood as 

they 



were 



the first day the malady came under the 
observation of the European physician. This disease, 
therefore, toget^Hr with the modes of treating it, offers a 
wide field for medical inquiry. 

Some curious information may be occasionally obtained 
in distant countries relative to the m.odes of treating 



diseases amongst uncivilized tribes ; not that it is likely 
to prove of much value, but as a matter of history it 
may be worth recording. It would even be interesting 
to know the virtues attached to charms and amulets, 
as well as the manner in which they are obtained, of what 
they consist, and how they are worn ;' nor would the 
methods of performing surgical operations be of less 
interest. The Alljanians, it is reported, without the 
slightest knowledge of the anatomy of the parts, perforin 



the operation of lithotomy with as much dexterity and 

as has ever vet been reached in this country. The 



succes 



Af] 



may be found, with little display, performing the initiatory 
rites of Mahomedanisra on the assembled youths of an en- 
tire village ; while the Fetish man, on another part of the 
continent, ministering to the pride of caste, makes su(^li 



fearful gashes on the faces of his patients as would 



1 



J 



^i.\ 



>*'"■ 



^ . 



I'-'- 



3 



L , 1 



^^ ^ 



l> 



r the 



i\ 



ri^r>-t^ 






I liivCiJ 



•it 



^ r 



1 1. 






1 "r i -.1? 



1,1 



of 



^ 1 



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p 



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f 



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r 






:-* to 



^n'V 



fan 



ei 



.r of tl 



cU[( 



^•OU' 



11 



1 



Sect. XIV.] MEDICINE AND MEDICAL STATISTICS 






se wounds are 



astonish our boldest practitioner. How th- 

cured mirrht be worth knownig, as the scars sufficiently 



attest the excoUence of the surgery. 

In the central parts of Africa, and in some of the 
islands of the Indian Archipelago^ there is reason to 
believe that the natives are in possession of narcotic 



poiso 



ns 



.vith which 



Wo 



fn 



'- a re sii 1 1 unacq uainted. An 



5 



account of these, and of their modes of preparing them 
would be hiteresting. And on all occasions the diseases 
most prevalent in the various foreign countries visited, 
and the most approved methods of treating them, together 
with an account of the medicinal plants, and other means 
in general use as remedies, should in conformity with the 
public instructions bo invariably reported. 



In preserving medical plants or seeds, or, in fact, any 



Zf"' 



other object of natural history, for the purpose of bnBging 
them to thi;i country, it will be found no easy matter to 
protect them from the ravages of insects, and in damp 
countries from the effects of mildew. The tin cases now- 
used for certain articles of dress are w^ell adapted for the 
safe keeping of vegetable or animal substances ; but wdien 
they cannot be procured, a tolerably large deal box, of 
a form such as will fit snudy between the beams of the 
small cabins allotted to gun-room officers, its seams 
being closed up by pasting paper inside, is the best 
substitute. From these all insects may be completely 
eicluded by placing loosely in them, scattered amongst 






the contents, several pieces of camphor, and rags 
sprinkled with turperthie : the latter will requii'e to be 



r emoistened now and then, A 



I 



oil of 



I 



Lr 

4 



-4 

r 
> 



i?*- 






462 



MEDICINE AND MEDICAL STATISTICS. [Sr-\ XIV 



SO protected neither ants nor cockroaches will enter ; and 
without some contrivance of the kind it will be in vain to 
attempt to preserve almost any object of natural history 

Lible substance ; unless it be planed 



o^ 



an ^.iiiuial 



o^. vx^getc 



tion 



of the chloride of zinc. The 
Iatt(3r5 ai= it is now generally employed in all ship?i of war 
for the destruction of vermin and fetid exhalations from 
the holJo, U not only the .ost available, but in other 
respects it is t'^^ ^ best, the d.^^apest and the mostgener*'"^^ 



V 




5eful. P^- pr ervative powers are equal to spirits, while 
even w^hen the most putrid substances have been immersed 
in it, it remains perfectly free from the noisome odour 
which animal matters impart to the latter^ and which 
renders the opening of any jar in which preparations are 
kept a nuisance, which few men would v-nture to inflict 
on their .liipmates. The strensjth used by the curator of 

the 



M 






an at Ilaslar, for fish and reptiles, or, when m 
g^nd condition, specimens of morbid anatomy, 's in the 

part of the concentrated solution to 
twenty of common water ; but when they are very putrid 

namely, 



proportion or one 






y require at liiol a much 



stronger mixture 



5 



about equal parts of each. In ^his the preparation is 



allowed to remain until tu^ &mell is qu'^c subdued, wheu 
it may be finally put up in a solution of the f -^t-men- 
tioned strength. 

It w^ould greatly enhance the value of the mediciJ 



•^r^4- 



^tunis if, in addition to those now required by the printed 
instructions, tL..: were an additional nosological returo 
sent in annually, commencing on the 1st of January, or 
on the f^^y the shin was commi?-^oned. and ending: in- 



va^riablv on 



^ V 



jlst of December. 



5 



or, m 



the event of 



her being paui ofi^, on the day she w^as put out of com- 




V. 



H 




''^ 



>* 

-*!. 



L 



y 
I 



{ 



1 ' ' 



^^•^^ 



^■^u 



) 



• rt 







--VT 



1 Vi 



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ricte 



1 retui' 



iiiar)' 







of 






c 



•oin- 



'S-^ri'* 1 f^O 



Sect. XIV.] MEDICINE AND MEDICAL STATISTS 



N-'S 



463 



miss] on. 



In this the m 



► 



i il 



TJuiuerii^aJ strength of tli 



e 



ship's company should be noticed, together with a list of 
the men dead, specifying their names and the causes of 
death, whether from "ccident, disease, or suicide : whether 
occnrri'^': on board, oi^ detached sc-vioe^ou shore, on leave, 



or in hospital. The name of each person dead is essen 
tially necessary, to prevent one deatli being twice noticed, 
an error which, were it reported both from a hospital and 
the ship to which the man belonged, it would be difficult 



to avo'uL By following out these plans the exact mortalit 



V 



of the f^'vice 



could be ascertained 



tro 



gr 



At present this cannot be 
accomplished without a long and patient examitration of 
various data, involving an unnecessary waste of time and 



much labour, which in the end is unsatisfact'Ary, inas 
much as it is impossible to arrive at anything like the 
correctness which ought to stamp the character 



fall 



5itatistieal details, as ari 





s. 




Moreovi-r, at present there is not any means of formin 
even the most distant conception of the relative loss of 
service per man from sickness in any given force, m the 



course of a year; nor of the number oj "-iays sicuness 
attributable per man to each disea^ ?-parately ; or, in 
either case, of the mean loss of service in comparison with 
the number of attacks. These are points of consider- 
able importance in a statistical point of view, and mness 
tiiey can be ascertained, it will be ira| -siblp to form any 
correct estimate of the health of the navy in comparisoi 
with other bodit>s of men. 



i 



The additional information required to carry out tli'^se 
calculations being in the hands of the medical officers oi 
the navy, it is to be hoped the time is not far distant 



» 



^^* 






V 

1.". 



V 



464 



MEDICINE AND MEDICAL STATISTICS. 



[Sect. XIV. 



whfcii it wiil be generally furnished. For the sake of 
system it will be necess'"-y to add an additional column 
to the sick list, in which to state the number of days each 
case was under treatment. 



:\dding these together at 



the close of the year, and dividing the aggregate sum by 



the mean numerical strensftl 



o-^^h 



will of course give the 



proportional number of days' sickness per man for the 

The relative proportion of sickness, with respect 



year. 

to diiferent diseases, mav also be ascertained. 



T' 



a 



additional trouble (if indeed I 
which these details would L 



expose 



id be BO -considered) 
divided aiuongst so 



many, would not be great, while the facihties they would 




5 and the correctness they w^ould insure in the com- 
pilation of the general details for the v/hole service, would 



be of the utmost importance. 



-■H* 

^ 



There is still anoth(T object which would add greatly 
to the interest and value of tlie vital and medical statistics 
of the navy, and this cannot be effected at head-quarters 
unless by the employment of an extensive staff of clerks 
namely, to class the whole of a ship's company by their 
ages into decennial periods, beginning at fifteen and termi- 

fifty-five, in order to ascertain the relative 
degrees of sickness and mortality in each of these stages 
of life. By a propt. arrangement of these and the pre- 




ceding data, in tabular 



r* 



forms, the relative amount of 



■*i 



sickness at certain ages, and from every, or, at all events, 
from the most important diseases, might be deduced, and 
the relative deg • 3 of health enjoyed not only in different 
squadrons, but in different ships, ascertained by a single 
glfsnce, and with a degree of accuracy which it is impos- 
£'He to arrive at by the present system. 



*l 



rir^^- 



.yi- 



1 



n 



)lllv>,.^ 



i 0- > 



■4 , 






I 



( 



465 ) 



Section XY. 



^ 

r 



> 



^ ■. 



M\, 






1 

T 



S T A 



I S T I C S 



By G. R. porter, Esq 



iO 



1 1 



u 



L. ■_* 



^*^ <■! T fi 






J 



ito' 



r 

t 1 



h-- 



1 ..:: 



V f 






the p" 



L - 



1 ntld 



.'^ .,.-.i^T 



.:^<Tle 



a - 



^i-^ 



y^ 



, ^'.^p^'^ 






The population of any place or country must be consi 
def 6(1 as the srroimdwork of all statistical inqiiiry concern 





ing it. We cannot form a correct juc 

any community until we shall have become acquainted 

with the number of human beings of v/iiich it is composed, 

nor until we shall have ascertained many points that indi- 
cate their condition, not only as they exist at the time of 
inquiry, but comparatively also with former periods. 
In the section of this volume which is devoted to geo- 

directions are given tor collectins 



usmo- different Ian^uai'^<^s or 




graphical observations, 

the actual numbers of the population, a branch of inquiry 

which properly falls within the pro^ance both of political 

geography and of statistics. The division of the inhabitants 

of any country into races, 

dialvots, belongs to the first named of the two section?, 

and need be no further noticed here. 

The actual numbers of any population can never be so 
saiisftictorily ascertained as by the interference of the 

a 

govenimcnt, and the first inquiries upon the subject 
should be for official enumerations. Where such do not 

t 

^ 

, exist, it may still be possible to procure data for 

; X 3 




4l 



4 

? 

\ 

L 



i 



466 



STATISTICS. 



[Sect. XV. 



m 



factory computations from governmental departments, and 
especially those connected with the taxation of the coun- 
try : but it must be evident that, to render such data 
available, the eircumsiaiices riudcr which it has been col- 



1 

JL 



ected must; as far as possible, be ascertained and recorded. 
Where no official accounts cp^ he made available, recourse 



houid be had to private ch?iimels, giving the preference 



f^ 



to siv'h Btatemeiits (if snch exist) as may have been pub- 
lished in the country, and have thereby been Biibjected to 
criticism and correction on the part of those best qnahfied 
to form a judgrnoBt on the subject. Local registers are 
sometimes to be met witii, where the central government 



has not interfered. Such were carefully kept in many 
parisliea in En^band, before any government census wab 



midertai 






From 



ncn 



fi rxri 




throusli a series of years, 



cli registers^ comparing births with 

population of a 




country may be estimated with some approach to accuracy. 
The rate of mortality is a fact of so much importance 
towards any useful knowledge of a country, that 



it IS 



natural I y am ong th e sub j ects of in qui ry that should 
earliest command attention. If registers of bui L^loj which 
record the ages at which the deaths occur, can be obtain^^''. 



they would elucidate many points of ^rreat interest nj> to 



the condition of the people and the effect of the cHmate, 
a-r 1 would besides afford means, in connexion with die 
number of births and marriages, for more nearly ap- 
proximating towards an accurate estimate of the popu- 
lation. Where a censr- '^^^ been taken, a distinction will 



doT- ^ ties? have been made between the sexes : c...l if the 
ageft also luwe been recorded, the tahles will themselves 
afford means for testing their general accuracy, as it may 



b 

ye 



a 



4 



^'"'■-.- 



■^ ^ 



^ r 



U.V 



I ^^ 






^\^v^^ 



ren-^p 



' \. 



1* V 






^t 






1 



I ^f a 






^ 1 



< 1 



V. 



v: I 



1 



k 



'1 



H 



..1 



^ ' 



--^ 






r 



^1 



ic 



If -' 



1 



-1 



'-'^' 



ll ^^^> 



-\ 



Sect. XV,] 



STATISiic^. 



467 



ba assumed that the proportion of adult males~4wcnty 



years 



of Pif^e and upv. :irds~are about one-fourth of the 



w])ole population. Where no census has heei 



4-nl 



kexi^ it 



A 

Should all other 



sources of information be wanting, it will then be neces- 



that is, of males between given ages. 




sary to have recourse to oral information, in estimatin 
the correctness of which the observer must avail liimself 
of such aids as present themselves. The question whetlier 
a community is increasing, stationary, or diminisliing, 
mav be iudged from the amount of buildings in progress, 

«/ JO 

or of houses untenanted or in a state of decay. If any 
account is talfen, for purposes of taxation or otherwise, 
of the number of inhabited houses, and especially it these 
should be divided into diflerent scales, a little personal 
ob?,ervation as to the average numl)er of inhabitants to be 
found in ear/n will furnisli valuable h.formation concerning 
the population ; but to do this, the inquirer must inform 



himself concerning the domestic habits of various cltu^es 
of the people ; the necessity for which caution will be 
made apparent by the fact, that while in all England the 
average number of inhabitante to each house is under 5 4, 
the average number in the metropolitan county exceed 
7^ ; while the number to each house in Dublm is 12|, 
which is double the average number in all Ireland, wl--re 
the house accommodation is generally of the mc... wretched 
description. 



s 



all 






Having ascertained, as well as circumstances 
the numhers of the people, it becomes of importance to 
know how they are employed. It cannot be expected that 
any one, who is without the authority of th( 



'^ L.- 



\ernment 



i 



46 8 



STATISTICS, 



[Sect. XV 



for the purpose, can succeed in ascertaining with minute- 
ness the numbers occupied in each of the various branches 
of cmploymeat, but opportunity may probably be found 
for ascertaining those numbers in certain great ieadino* 



divisions. 



fiillowing in this respect the more usual course 
of inquiry in this country, and distinguishing individuals 






n 



culture 



towards estimating the social condition of 



imfactures ; and, thirdly, in all other pursuits. By 
knovving the proportionate number of any people who are 
employed in raising food for themselves and the remainder 
of the community, we possess a very important element 

the people. 

The truth of this remark is made apparent by the fact 
shown at the census of 1^41, that while in Great Britain 
251 persons raised the food consumed by themselves and 
749 oH.er persons, or while 1000 persons engaged in agri- 
cultural labour supplied the wants of 3984 persons, 
including their own ; in Ireland, in the same year, the 
labour of 662 persons was required to supply food for 
'■■-•emselves and 338 others, so that 1000 persons supplied 



included 



The 



fbud for only 1511 persons 

deduction, to be drawn from the like facts in other coun 

tries are liable to mo 



*• 




on, and particularly if it shall 
appear that families, or any portion of them., which draw 
their chief support from agriculture, employ any portion 
of their time in domestic manufactures. Previous to the 
inventions of Arkwright and Hargreaves, the spimiiiig 
wheel was in general operation in cottn Q-es throughoiit a 
great part of Enj^land ; and the time is yet more recent 
at which the shuttle mieht be heard in those cottages 
luring the long evenings of winter, and at times when 



t: 



h 



fa 



t 



! 



■■^«M*. 



I. Xv 



ni]tr, 



1 



< 

H 



r' > 



^^■U'i 



I 



) 



10 



- li 






, f 



- -I- 






L ^ A V^ J 



P ^f ^i*^ * ' ^ 



r. ^ 



^. 






--I'S 



1 . ^■ 



T/ 



receii^ 



f 



ff 



^fli^ 



f 






< 



\. 




Sect. XV.] 



STATISTICS. 



469 



+^ 



out-of-door labour was prevented by bad weather. Hand- 
loom w^eavmg, except as the substantive occupation of the 
familv, may now be said to have ceased in tliis country, 
and the spinning-wheel has long been wholly superseded ; 
but this is far from being the case in many, or perhaps in 
most, other countries, where the females of a faoiily are 
at timus employed in spinning and weaving, at least for 
the supply of their own household, if they do not provide 
a further quantity of fabrics for sale to others. 

Where manufactures are carried on in fectories or large 
establishments, it will not be vei v difficult to obtain a 
tolerably accurate estimate of the number of such esta- 
blishments, and of the hands employed in them. In some 
countries, the government requires that a patent or licence 



shall be taken out yearly by the proprietors of manufac- 
tories, and by this means a correct account of their num- 
ber might be obtained. In the same w^ay, the number 
of dealers may sometimes be ascertained, and probably 

classified as being wholesale or retail traders, as w^ell as 
distinguished according to the branches of business pur- 
sued by them. 

It is desirable to know^ the usual and avera^ze 



size of 



farms or holdings of land, and the system under which 
they are cultivated, whether by the proprietor of the soil 
or by tenants ; and if by the latter, then upon vrhat terms, 
whether by payment of an annual rent, and 



at wnat 



rate usually for a given measure ; or by a division of the 
gross produce, and then in what proportion the landlord 
participates for the mere use of the hnd and farm- 
buildings, or whether he furnishes tlie stock or any pro- 
portion of it. Inquiry should be made as to the existence 



; 



V 



4 



( 



« 



i 
i 



4-70 



i \J 



STATISTICS. 



[Sect. XV, 



of what is iiiKierBtood by ^^ tenant-right ;'^ whether by Lv. 
or by custom the farmer is entitled to cojupensatioD for 
such inmrovemeiJits as he may have made in the condition 
of the land. The number and kinds of live animals that 



are 



tained 



bred and kept upon farms should if possible be ascer- 

the number of labourers usually em- 



as well as 



ployed upon a given extent of land ; the rate of wages 
which they receive ; whether those wages are lessened by 
reason of their being boardod by the farmer, or whether 



c 




they live and board themselves in separate 

also wliether there i- employment on the farms for women 



\ges ; and 



JL V 




or chi-'bai, with the rates of wages paid to them: and 

]f the labourers have any other advantages in aid 
of wag:es. 

If it be important to know how the people of any 
country are employed^ it cannot Ijc hjss so to ascertam 
the result of their labour. It is especially desirable to 
know the proportionate quantity of each kind of fooc 
raised upon farms of a given size, or upon any known 
measure of land of the averaii^e degree of fertility : the 

O CD y ^ 

quality of such of the cereal grains as may be raised will 



best be ascertained by learning the weight of a given 



quantity by measurement. While making inquiries con- 



cerning the supply of food of home growth, it must be 
essential to ascertain whether, in seasons of average pro- 
du'-^'vencss, that supply is equax .o or greater than the 
ordinary consumption of the country. Should it fall short 
of the requirements of the people, inquiries should be 
made concerning the quantity deficient, and the sources 
whence the same is ordinarily made good. On the other 
hand, should the home produce exceed the consumption, 



{ 



XV. 



'1 



-i 



^ 



> t 



r 






^v* 



r 






V 



it 






'IDV 



1 

1 



Mp to 



n 



J 




^ will 



5 t'fil- 



2P 



1-0- 

tlie 



i 



-I 1 U.' 






V 



J 



\. 



i 



Sect XV.] 



STATISTICS. 



471 



anne 



J 



for dispobing of it shuuid be ascertained. 




Similar inquiries should likewise be made concernm 
the mineral productions of the country. It will not be 
enough to know only the number of persons epiploycd in 
mining operations, since the value of such lalour \aries 
exceedingly in different countries. It was ?^- led at the 
meeting of the British Association in 



1844, thai 







d- 



workman empioyed in toe coal-mines of France raised no 



,ge tliajn no tons iii uie y^'ar^ wliue tL 



inmers 



was 253 tons. 



Tepa 



lal- 



Great 



four limes that made in France, while the number of 
persons employed for the purpose is actually greater m 
France than in Endand : the numbers actually so em- 



in France, 47,830, wh** mad 



ployed in 1841 were, 
377,142 tons of pig-iron, and in England 42,418, who 
produced 1,500,000 tons of that metal; so that the 
labour of each man in France produced barely 8 tors, 
while in Great Britain it sufficed to produce more than 

35 tons. 

The like inquiries should be made with reference to 



pat 



ccas 



offers or may be 



--^ 



found. Upon this subject it is essential to know the 
number of hours in the dav during which, at various 



seasons 



of th/' 



year, workm^en are ordinarily employ^^d, 
whether the routine of their occupations is disturbed by 
the intervention of hoiidavs, and to what extent such in* 
terruptions are carried in different branches of industry. 






Z^ 






A '1 




STATISTICS. 



[Sect. XV . 



Al«o, whether any and what restrictions are placed by 



law 



or custom aga-nst the employment of women or 
children in any branch of trade or manufacture. Na- 



turally connected with these inquiries is the share which 
the workpeople obtain of the value of the objects upon 
which their industry is employed. To ascertain this it is 
not only necessary to learn the usual rates of daily, or 
weekly, or yearly wages paid, but also the amount which 



a family of average industry, consisting of a man, his 
wife, and say four children, are ordinarily able to earn 
in the course of the year, including such perquisites as 
custom pro^ddes in aid of the ordinary wages, the nature 
as well as the value of which it must ^^^ interesting to 
know. It hardly needs to be said that a distinction must 

^^k — 

be draa^n between the e^mino-.^ nf tliA Qinio^i ot..i a....~.^ 



*^ 



who are unskilled, those whose qualifications are the re- 



sult of a previous expenditure of time and money, that 



IS, of 




and those who bring little more than 




their bodily strength to the performance of their task. 

does it need to be pointed out, that however 
numerically important are the classes usually understood 
by the term workmen, their condition does not comprise 
the whole of what it is desirable to know in forming an 
estimate of a community ; the circumstances of the better 
educated portion of the peoplr., including those who by 



tiieir studies and acquired skill influence so greatly the 
general ndl-being, and upon whom mainly depend the 
progress of civilizatioia, are to the full as necessary to be 
known. It will probably not be difficult to learn^ as re- 
spects these, the fees paid to professional men, such as 
physicians and advocates, the salaries of schoolmasters 



^d 



\ 



\ 









t 



.. ^ 



) 



■^ or 



u' 






>4 . 

J 



u 



*c 









:ll 



tA 



^j 



1 



li 



V. 



^ '.^ 



1 









It: 







d 



- T 



4-** 



^ /T^ 



au 



, ..]. 



. * '-'' 



ly the 



U) 



h(> 



1,3? 






i 

1 



.i 



/ 



i 



Sect. XV.] 



STATISTICS. 






as 



^^ the salaries eind other emolu- 



ments of men employed in the higher and in the mor^ 



subordinaL. offices of the government. 



Coxipl 



F*- ^ 



ed With 



these particulc.s we should endeavour to ascertain the 
necessary expenditure of families in the \ arious walks of 
life. This is a more difficult task, and it requires much 



/^ 



i^^ditions of the communitv to 



knowledge of the various 
estimate the correctness of such statements n- may be 
gathered, especially as regards the expenditure of the 
poorer classes. It is a curious ftict, that in almost 



fferv 



case 



where details of this nature were offered to the 
Commissioners of Poor Law^ Inquiry in England, the ex- 
penditure as stated was found upon examination to exceeu 
in no small degree^ ^he income of the family, altliough the 
parties affirmed that they did not run in debt. li must 



greatly help towards forming a correct estimate if the 



retail prices are ascertained of different qualities of the 

articles used and consumed in families holdini 



various 






different ranks in the scale of society. The incomes oj 






fX 



of public functionaries, the 



ilersfv 



very important class 

it may be more difficult to ascertain, especially in lands 

which have made a comparatively small progress in civi- 



avails 



ligation, and where it is understood the priest often 
himself of the superstitious terrors of the ill-informed 
peoph^ to advance his own personal interest. In other 
coimtries, comparatively free from this evil, it is, how- 
ever, no^ easy to ascertain the average rate of iT»^*ome^ oi 



AV^ »0 



source 



the clergy, wh''"h may be derived p-^rtly from o, 

and partly from another, — ^.oinetimes from the State, by 

n direct payment ; sometimes from land, the profit of 



f* 



/» 



some 



e^ 



W^ 



474 



STATISTICS. 



[Sect. XV. 



Sec 



given tor the performance of certain religious offices, such 
.., Tuarriagc, baptisui, and burial ; and sometimes also 
irom voluntary payments, or oiferlngs, in acknowledn-ment 
for the instruction and consolation imparted. Nor will 



the cases bo rare in which several of these sources are 

to make up the income. It will be 



con? 






ed, in order 



more 



:isy to learn the number of the clergy, and to 
ascertain the manner of their appointment, whether by 



election on t'^'^ part of the 



Deonle 



? 



or by nomination on 



the part of the government or of individuals ; and an esti- 
mate may be made of their general incomes by observinr^ 
the clam of the community among whom they usually live 
upon a footing of eijuHbty. 

There is no subject which v?ill so well enable us to 
judge concerning \hr- progress and probable ftiture con- 
dition of any people, as the state and decree of instruction 



which is provided for the vouthful among tham. The 



inq uL cr will therefi:)re endeavour to learn, not only the 
number of educational establish nients and of stiH^.^s 
attending them, but also the nature and quality of the 
instruction imparted ; the proportion of schools connected 
in any way with the State, and of those established and 
supi'-rted by private means. It will not be difficult to 



judge from observation, and also through conversation 
witli the inhabitants, how far the means provided have 
been effectual in fornier times in rendering the people 

•ost of 
instruction should also be learned, and whether in any 
and w'-' degree that cost is borne by the government ; 
also whether any and what degree of proficiency in the 
usual branches of knowledge is requisite to enable any 



intelligent and in warming their characters. The c 

:t ' if 4 o 



< 



V 



e 



a^ 



■vv 



1 







.f 



in 
ac 



> 



m 

ol 
1 



g 



w 

b 

c 



c 



c 

t 



1 



1 



i 



X\ 



tl.l 



■^ als 






cr- 



ftO 



-.1 



Jl' wili 



fees .V, 



♦■ ».M 



::!ll 



!)e 



^'" by 



M 



an '^^t,. 



ir 



n. T 



* 



*i'tj 



l« ■:: (0 



ufP 



at 






. T^e 



it 



'U '•* 



1 



w 



;ia 



g..)t ^0 



— f 



U' 



1 -a 



m 



?. 

>'-' 



.4 



in 



t' 



ac) 



i-ntiii^ 



nfiit ; 



,10 



t!ie 



, * 



f 









Sect. XV.] 



STATISTICS. 



475 




■lai dutica, or to 



person to take upon himself an) o 
authori - ^-mx to assume certain responsibilities in society 
Jiere the fortunes, tlie happiness, and it may be the r- 
of others, mil be intrusted to his ch 






Closely connected with this subject is the state of c:':ne 

The number of prisons, the amount ot 



in every couotry 




accommodation which they afford, and t^- number ^ 

inmates usually to be found within them, should, if possible, 

be obtained, as well as £'-ie acqudntance with the system 

of punishments pursued and the treatment of prisoncrs. 

The number of executions that have taken place within a 

given nuuihor of years, and the nature of the crimes for 

which tliat extreme punishment has been hafiic" d. should 

be ascer^-nned. If any mure general record of Wiender- 

can be had. it would be well to inquire the prices of food 

during the particular years to which those reco-ds relate, m 



order to jud 



ige c 



orrectlv concerning the m.oral c^ -"Meter 



of llie people under on: of its most important aspec' \ 
tendency towards c.hninal courses. To know the r 



its 



i -. 



i 
a 



generally, of the offenc.o committed tmII give us an ...signt 
into many subjects of interest, provided the people have 
made any considerable advances in civilization ', but li the 
country should be very backward in this respect, many 
crimes will go " unwhipt of justice/' If tl^e criminal re- 
cords of England existed for any period further back than 
half a century, we should probably se^.^h them in vain m 



order to learn the number of pickpockets ; not that 



tbe 



\ 



offence of picking pockets was unknown, but that when 
the offender %ws detected the mob took his pumshm...l 

pumping upon him, or 
horsepond, or by some otlie- 



into their own hands, 
dragging him through 



and by 



476 



STATISTICS. 



[Sect. XV. 



Sec 



more convenient summary proceeding, satisfied tlicir view. 
of justice, and let the culprit go. It is very desirable to 
knr among what classes of people offenders are chiefly 
found : whether among labourers in agriculture, or handi- 
craftsmen, or others r 



and also whether educated persons 
add in any, and in what degree, to the list of culprits. 
It is highly important to draw a distinction between male 
and femah offenders, since their proportionate numbers 
will throw light upon the general character of the com- 
munity in some of its features. In the early part, of the 
present century there were 40 females to each 100 males 
committed for trial in England and Wales : but during 

from 1838 to 1847 inclusive, the average 
^ roportion has not been quite equal to 24 in each 100, 
indicating a change in condition, manners, and morals' 
favourable to the present day. It is equally desirable tJ 
-now the proportionate numbers of juvenile otfenders 



the 10 vea 

9/ 



P 



classing under that head all under 15 years of age, or 
sucii other period of life as, under the influence of climate 
or any other cause, may determine the date at which the 
youths of the country generally assume an independent 
position and provide for their own support. It will be 
well to distinguish the sexes of these young offenders. 

By making inquiries of intelligent residents it raav be 
learned whether, with the progress of time, criminalitv 



T 



has increased or diminished in the country. The crimind 
records, if such exist, will by no means ftirnish data upon 
which reliance can be placed fbr judging upon this point, 
smce it often, or it might be said, most frequently happens 



that with advancing civilisation 

a coimtry are more strict; besides' which 



5 

the police regulations of 



increasing 



po 

llU 

na 

thi 

T! 

if 

of 



cr: 



es 
na 
es 
he 



sh 



S^ 



k^ 






It 



SC 



a> 



ai 



in 



Ti 



C( 

e< 
r( 

tl 



a: 



II 



1 



•D 



11 



f^^' JP_- ^t . 



XT 



t I 



? , 



-'Oie tn 



cV- 



p 



ii 



-J 



Onv 



per 






am 



].., 



'- w 



'- CODl- 

t of the 



t\ 



verage 

.u 100, 

morals, 
Fr' 'e to 



^jnder^ 



5 



"'^. or 



i: 



r^^ f> 



^e 



• 1 



ht!ie 



nr 



, „ ill be 



f ., 



k"- 



rs. 



-> 



.-:^qi;rv 



J" 



-nal 



ir 



oon 



P 



oi^t? 



itlO 



- 



J.>' 



f 



re^ 







ft 



^' I'-iiue I 



Sect. XV.] 



STATISTICS. 



% i-irj 



population, and increasing w 



ealth, m;^^" lead to a greater 



number of offenders, without really i ^-'ng to th^ crimi- 
nality of the community, since the nature and quality of 
the crimes committed may have bc^^ome less serious. 
The number registered in the calendars will be increased 
if two cases of petty larceny shall have taken the place 
of one murder, and yet no one would thence affirm that 
crime has increased in the country. 

The provision made for the indigent 




e 



nerally, and 



especially for the sick and the aged among them, will 
naturally call for inquiry. The number and extent of 
establishments answering to our union-houses, alms- 
houses, hospitals, dispensaries, and lunatic asylums, 
should be sought for, with every particular that can be 
o-athered concerning the manner in which they have been 
estaWished and are supported, and the number succoured. 
It would be a service rendered to an important branch of 
science if the numbers, in proportion to population, are 



ascertained of lunatics, of blind persons, and of the deaf 

and dumb. 

The length and condition of the public roads should be 
inquired into, as well as the system under which their 
repair is provided for, whether by the State, or by tolls 
collected from passengers, or by the money or labour 
contiibuted by residents in the districts through wliich the 
roads are carried. The modes of travelling, as well as 
the nature and number of public carriages ; and whether, 
as in some countries, they are the property of the govern- 
ment, or, as in England, the result of private enterprise^ 
hould also be ascertained, as they easily may be. The 
means for internal navigation, whether by rivers or os 



^ 



I 



47 



78 



STATISTICS. 



[Sect. XV 



artificial canals, it may not be difficult to learn ; recording 
the direc Lion and the length of each, and the size of 
sels in which the traffic can be conveyed. In the case of 
canals, it will be interesting to know tiie date of their 



ves- 




^^-■-uction, and, if possible, their cost, as well ds the 
nature and amount of goods conveyed upon them (and 



y 



srree 



which their construction has answered, both for the 
advantage of the community and the profit of the owners. 
ITie interest which attaches to railroads, in most places 
where they have been introduced, has been such as to 
cause every publicity to be given to their statistical 
conditions, and printed accounts, in which every question 
that it may be necessary to asls concerning them may be 



easily procurable, and should be secured. 

The manufacturing industry of a country will naturally 
claim attention from every inquirer, who, in the probable 
absence of all precise inforraation concerning its exto..t, 
will endeavour to supply its place by means of such cir- 
cumstantial information as he can bring to bear upon the 

With respect to such branches of manufacture 

raw^ material upon foreign supply, it 



as depend for their 

will not be very difficult to arrive' at a tokrably close 
approximation to the truth, in regard to the quantity of 

ch cases are comparatively fev.^, 



SI 



use 



bl 



7 
A. 



however, and with regard to those branches of iudustrj 
which derive their material partly or wholly from the 
r: tr-e soil, the person who visits any countrj^ must usually 
content himself wdth such statements as he can draw from 
trustworthy persons, preferring those accounts, if any 



such there be, which, having hcen published to the world, 






Sect- - 



have 



.-^ 



man 



a^ 



go 



I 



man 

we < 

url 



ai 



sai 



k^ 



vail 



ma. 



mm 
pre^ 



Th 

the 



i 



KK^v 



an\ 



Ti 



lI 



COIj 

the 

fir- 



car 



li 




0U1 

p- 

f; 



f. 



lot 



^^^■^-x 



■c 



■^ 



l& 



'\.. 



X\ 



Sect. XV.] 



STATISTICS 



479 



A < 



■^ai 





.-> 


' C-'^y. n 


*^l 


^UU- 


' "s the 


\"^n> f , 


\^'*u 



C^^v, ill 







T — - 



'1^,:^ 



.^t 






I * 



■-- W 



icli as to 



W 



ofi f'-^ .1 



'■^\, .. 



^ 



^-lestion 



Ll. 






\-i 



[ 



Ti 



J 



prol^ . 



jj 






i. 



■' cir- 






TiV. 



rp 



iSM- 



1 



■'^ 



,11 



■ -^ 



-J 



1 



rt 






T ' 



4 

' 



P l^au^- 



fl^fi 



L -^ 



r> 



'\ 



I'- 



r -n 



ir** 



«.*' * 



- II ' 



^hi 



VI 




have stood the test of local criticism. The 

are exainpl^'^ of the iirst- 

meutioned of these coiiciitions, while our linen and woollen 



ilk manufactures ot England 



manufacture 



s suffiuicncl" 



J explain the 



,t] 



1 



other Class. 



To 



ascertain merely the quantity of raw material used would 
o but a little way towards determhiing the value of anj/ 




manufacture to a country. This will he jjlainly seen if 
we '-all to mind the ^miliar instance of the ch-in-cahlo 



and the watch-spring, both of which arc products of the 
same material ; while one, by reason of the amount of 
labour bestowed upon it, is many thousaud fold more 
valuable, weight for weigiit, than the other. ' The cotton 
manufacture is open to the like dimculty, although in a 
minor dc>grce ; even the yarn, which is the result of a 

prelimlu...ry process, sell 

ness, from a few ^.^nce to as many shillings per pound. 



deOT 



The inquirer vxll, therefore, feel it necessary to ascertain 
the increased value that is ordinarily imparted by pro 
ce.ous of manufacture to the materials 



used, and Mhether 



any and what changes are going forward in this -spect. 



The inform ' ation here suggested may partly be gathered by 
comparing the prices of given weights and measures of 



the materials with those of the average qualities of 
finished goods ; but it must be evident that little mure 
can be done in this bv^..ch than to apply to men of intel- 
ligence and rc^pectahllity for such info^rmation and ophiions 
a:, they may be able to impart. It need hardly be pointed 
out as desirable to know in what degree the general po- 
pulation shares in the use or consumption ot home-manu- 
factured articles— whether any part of them tails to the 



clas 



V 



-^ 



480 



STATISTICS. 



[Sect. XV. 



engroB-3a by the high-born and wealtliy. It is desirable 
to kn y whether any, and what, braiiche- of manufkcturfi 
are carried on bv fore 



amers 



workmen : also, if women and children find einplo^Tiient 



gre 



which the various classes of the manufacturing popnlatiou 



S 



live, is greater or otherwise than the comiort enjoyed b\ 
those who follow other occupations. It is of importanci. 
to learn whether any manufactories are mainfr":ied ^j. 
assisted by the government, ana in what form that assist- 
ance is given ; whether by direct money-payment or by 
the grant of privileges or monopolies ; and in case any 
such system is followed, then whether in the branches 
thus favoured there is found a greater amount of success 
than ordinarily attends the employment of capital r ' I skill 
in the country. The seats of the several manufactures 
should be indi^mted ; and where any mechanical power is 
employed, the nature of the sam.e should be explained : 
and also the degree of proficiency attained in the produc- 
tion of machinery, when it is made in the country, and 
if it is brought from abroad, then the places whence 
such raachinery is r*-^riyed. 

The foreign commerce of a country is matter of especial 
interest to every other country, and more particularly to 
England, so much of whose prosperity depends upon it; 






commercial relations. Among the earliest inquiries to be 
made on this head will be the .amount and description of 
the shipping under the national flag, and whether the ^ a^'ie 



be increasing or otherwise ; whether any, and what, nrivi- 



leecs are accord 



' ^, 



1 



to tlic native marine. 



Then, w 



hat 



other flags frequent tlie ports, distinguishing those v/h:.^ 



..t XV 



>ect. 






^riic'ip 



nostly 



io the c 
The 









a''C( 



OUii.t 



P- 



'! 1 



^ 






into >H"^ 
them n 

clothinG 

obtain^. 

Jx is '^ 



*^^recii^ 

^ '' rci 



course i; 
DO proc. 



will s 
d \ 



er 






t.( 



nne 



% 



1 



if 



fr - 



,-* 



to 



'V 



-lit a 



)*^iU 



w 



"Ki 



\* 






^ '^•A 



of 
to 



i 



J -•- 



a 



■*Via 



ai 



4 



to 



T 

F 



m 



1- 

of 



* i 



< ; 



ot 



\j . 



1 



4 1 



' I'^iipl.. 



•:;' 



^r 



ID 



rl 



^VU V 



nanuf::! 



H o^ 



^, "i f n-il^ 






i. . 



I 



e/^ 



n". 



Mi^^ 



.\{^i 



1 i-r, 



r' 



r 



*,- 



■ iy 



k- 



i 



a*'- 



.; 



.er tii^ 



1 



.'1 



r 

If*' 



lIltB? ^ 



rf 



Sect. XV.] 



STATISTICS. 



481 



a-dcipate most largely in the trade, and whether they 
TDOstIv or entirely trade with their own ports. 



i 



or engage 



io the carrying trade from foreign countries. 



Tl 



n 



e 



description and quantities of goods imported and 









a 



^ V W 



learned 



iroin intelligent merchants, or, what is better, from the 
a ..,a..ts of custom-houses. Distinction should, as far as 
F"^"-''"? be drawn between goods imported for use and 

brought in transit, dividing them, in both cases 



■ 1 

Xiiv-^Jt — „. ujvii vcicta, 

into ..aw materials and finished articles, and classifying 
them according to their nature, distinguishing food, 
clothing, metals, &c. Tlie like statements should be 
obtained, and distinctions made, in regard to exports. 
It is desirable to know whether goods are imported 
rlhecily from the various countries of thpir production, or 
indirectly from third markets, and in this latter ^^e the 
rea=-ns should be sought why the apparently less desirable 
course is followed. The rate of customs-duties can always 
be procm-ed, and in most cases in a printed form. This 
will serve to show whether any differential or preferential 
do*' ^ are levied, to the hurt or advantage of particular 

their 






NT 
X 




^?. 



Co 



jtnes. 



In regard to duties upon 




■■ ' and nature should be sought equally with those 
I upon imports and consumption, 
home trade of countries, unless they be of such 



^^ 



,^^ :■_*%_ 



c..,v:nt as to include different climates, and consequently 
to s Aa different products, is usually comprised in trans- 

:g imported articles from the ports to towns in the 
luterKM- and to countr}^ districts, or in transferring articles 



J:- 



K^. 




i:^ 



o>' ^-.v.i^^e 




rowtli from the country districts to the different 
to',.o and ports. Besides this there will be, in manu- 

Y 



;-^-* 




482 



STATISTICS. 



[Sect. XV 



Sect 



X^ 



fantiirlng countries, the transmissioTi of goods from tlie 
seats of manufacture to the towns and villages, for t^'" 
supply of their inhabitants and of the neighbouring dis- 
tricts. A traffic of this kind it must be at all t'nes 



\ 



a 



difficult to register, and the most that can he done 
stranger or visitor is to learn the general nature and 
course of the trade, and to collect opinions as to its 
amount and condition at various periods of time. L 
any internal duties, answering to our excise-duties, 
are charged upon home productions brought into con 
sumption, their nature and amount should be a 

tained. 



The subject of currency and banking is oi very high 



-. r\.'\''/^ 



importance, and every information concernmg it that cm 
possibly be had should be carefully obtained. The natu, .; 
and value of coins in use, their weight and denominatl" . 
should be noted, and whether means are used to pre''>rt 
their exportation by laws passed for that purpose, or by the 
coins being made to contain any considerable portion of 
baser metaL If any auxiliaries to the use of coin should be 
established, such as bank or government notes, or trau.l.. 
in books of public account, as practised in some trading 



r 



cities in Europe ^ 



Harabur 



should be described. Until a recent period, the chitr, u 

payments in Fraui*' 



use 




was by the transmission of silver coin ; and it often i...p- 
pened that public carriages, passing between two pla- 
in opposite directions, conveyed at the same time --s 
weight of five-franc pieces. This inconvenient and ^•-- 



lesrre 



medied by the more general establishing of banks of issue 



5 



extend 
The 

the pr 
or to 

this SI 
use ar^ 
differe 

o-ard t' 
countr 

Englai 



] 



If I 
tradin! 

capita! 

and th 

interes 
Theri, 

yet clc 

be the 

and tl 

The 
publis: 
statem 
^•ith £ 

should 
will Si 

quarte 
In , 

will b 

with 11 

^egre^ 



'-.■^-j^,^ 



Sect. XV.l 



STATISTICS. 



483 




1 > 



] 



\ 



^l 



r^ 




ila • 



n 



h 



. 1 . 



L 



h] 



I 



( 



1 :• 



1 



I 



\ 



t 



vr 

r 



m 



1 






C ^ 



1 * 



V 



J- 



:it 



•w 



I 



hs. 



r- ' . 



^n. ;. 



u- 



.1 ' i 



I 



■'•I ' ■ 



whose notes are transmitted by post, as well as by the 



extended use of bills of exchange. 



The weights and measures in use should be stated, with 
the proportions which they bear to those in this country, 
or to other well known standards : and, connected with 
this subject, it is well to know what articles of general 
use are sold by weight and what by measure, and whether 
different weights or measures, or different usages in re- 
gard to them^ art adopted in different parts of the same 
country, as was at one time the case in different parts of 

England. 

If any joint-stock associations are in operation for 
trading purposes, their nature and the extent of their 
capital ; the peculiar privileges, if any, that they enjoy, 
and the effect they are judged to have upon the general 
interests of the community, should be carefully gathered. 
There may be other associations not strictly trading and 
yet closely allied to trading interests, which should equally 
be the objects of inquiry ; such as docks, insurance offices, 

and the like. 

The public revenue and expenditm-e of countrieSj when 
published at all, are put forth by the government ; an( 
statements of this kind should be made objects of enquiry 



d all 



with a view to obtaining the same. If the 




overnment 



should not think fit to publish information of this kind, it 
will seldom be of any use to seek for it in any other 

quarter. 

In every country, havhig any claim to civili2;ation, it 
will be possible to procure maps, and by conversation 
with men of intelligence the visitor m.ay get to know the 
degree of rehance that is to be placed upon their accuracy. 



Y 



^ 









484 



STATISTICS. 



[Sect. XV. 



APP'J 







The limited space that can be given in this volume to 



the subject of statistical cnquirit^s has necessarily confined 
the recommendations v/hich are offered to the more lead- 
ing or important objects, which are also noticed with the 
utmost brevity. To persons of intelligence who visit 



other lands, many peculiarities will present themselves 
which they will think worth recording, although nothini^ 
should have been said concerning them in these pages. 
One caution it appears desirable to offer ; it is, that no 
fact shall be disregarded as without value by reason of 
the incompleteness of the information it yields, since it may 
well be that this very fact may supply a link in the chain 
that will give value and completeness to former or to 
future observations* 







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PiAN and Rkoui-ations of the Establishment and Adjudication 
of Two Pkize MiiDALS for the Encouragement of the Medical 
Officers of the Royal Navy, and the Improvement of Physic and 
Surgery in that Department of the Public Service. Founded by 
Sir Gilbert Blane, Baronet^ First Physician to the King, 
F.R.SS., Lond.3 Edin., Gott., Member of the Imperial Academy 
of Sciences of Russia, of the Institute of France, &c- 

]. The Founder — considering how much it will conduce to the 
advancement of the Public Service that emulation should be excited 
among the Medical Officers of the Royal Navy by honorary distinc- 
tions fur professional merit— has vested the sum of three hundred 
pounds in the three per cent, consolidated Bank Annuities, in the 
corporation of the Royal College of Surgeons of London, in trust 
with the dividends which shalJ be from time to time receivable^ for 
the purpose of conferring, once in two years, Two Gold Medals of 
equal value on two medical officers, surgeons of ships of war iu com- 
mission, or assistant-surgeons of King's ships in commission not bear- 
ing surgeons, who, in the time required, shall have delivered into the 
proper office, Journals, evincing the most distinguished proofs of skill, 
diligence, humanity, and learning in the exercise of their professional 
duties : these journals to be delivered iu the form in which they have 
been kept from day to day, stating the symptoms as they shall have 
occurred at the time , but without prejudice or hindrance to 
making such observations, practical or theoretical, as they may jud^v 
proper to annex to them. 

2. The first selection to be made by the Medical Commissioners 
on the 12th of August, 1831, from the Journals delivered between 
the 12t.hof July, 1827, and the 12th of July, 1831. All future selee- 
tions to be made on the 12th of August, at the interval of two years 
from each other, from the Journals delivered in the two pre- 



>_ 






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486 



APPENDIX. 



L-^W' 



ceding years, up to the 12th of July immediately preceding such 
selection, 

3. In the selection of these Journals the Founder proposes that the 
Medical Commissioners of the Navy shall, out of the whole Journals 
delivered to them in the course of the intervals above specified, make 
choice of such as in their Judgment possess the highest degree of 
merits in number not more than ten nor less than five, which shall bo 
transmitted to ihe Founder during his lifetime, for his selection out of 
the number so sent, of two^ or one in case there should not be another 
of sufficient merit, the authors or author of which, in his judgment, 
may be most deserving of the prizes. And after his decease the said 
Journals to be conveyed to the President of the College of Physicians, 
whoj after due examination, is to communicate them to the President 
of the College of Surgeons, and after proper deliberation the said 
Presidents are to call to their assistance the Senior Medical Commis- 
sioner of the Royal Navy, and jointly with him select from the said 
Journals one or two, the author or authors of which, in the opinion of 
the mojority, possess the highest merit, and become thereby entitled 
to the Medal or Medals. The Medal or Medals when adjudged are 
to be put into the hands of the attending Medical Commissioner, to 



be by him presented to the successful candidate or candida^(^s. All 
the Journals of the first selection to be returned into the custody of 

V 

the Medical Commissioners. 

4, In case of the impossibility of performing the before-mentioned 
duties, through the illness or unavoidable absence of the parties 
described, the duty is to devolve on the next in rank ; that is, 
on the Senior Censor of the College of Physicians, the Ylce- 
Fresident of ihe College of Surgeons, or the Junior Medical 
Commissioner. 

6, In case it should happen at any of the periods of adjudication 
that in the opinion of the Founder, or of the two Presidents alter his 
decease, there shall not be found a Journal or Journals of adequate 
merit to entitle any candidate to the prize, the Medal or Medals shall 
be wiiaheid until the next period of adjudication ^ and the unadjadicated 
Medals are to be conferred on such as may possess sufficient merit 
over and above those subject to adjudication at that period. But this 
regulation is to be so construed and luxiited that no more than four 
prizes shall be adjudicated at any one period ; and if the unadjudged 






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oniit to 



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Medals should exceed this number, their value in money is to be 
given to the Supplemental Fund for the Children of Medical 

Officers, 

6. In case at any time the Founder or the two Presidents shall 
omit to make the adjudication for a longer period than three monthsj 
thev shall be considered as having forfeited their right, and the ulti- 
mate selection shall devolve on the Medical Commissioners, who, in 
case of difference of opinion^ may call in such a referee as they may 
judge necessary or advisable. 

7. The Founder shall provide and deposit with the Royal College 
of Surgeons the Die engraved for the Medal, from which they will 
cause the Medals to be struck at the pre^. Jbed periods, and to be 
delivered to the Medical Commissioners to be presented by them to 

the successful candidates. 

8. No successful candidate to be admitted as a competitor a second 
time. 



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9. Tbo Presidents of the Royal College of Physicians and Surgeons 
and the Senior Medical Commissioner to be considered as guardians 
of the *. I uud its equitable administration, 

10. Tu case any of those surgeons whose Journals have been given 
iu; sL,._ld have been paid off previous to adjudication, or should they 
have Li^vXi appointed to an hospital, or any other situation on shore 
^,,.-.pp|. iu..f f^j.' Medical Commissioner, such surgeons shall still be 
de ^ed eligible candidates for the Medals in case of adequate 
n.^iit. 

11. After a lapse of not less than ten years from the decease of 
the F nder it shall be competent for the Presidents of the two 
Royal Colleges and the Medical Commissioners of the Navy to hold 
an interview for the purpose of consulting whether any an 



^- 



d 



what 



additions or alterations would be advisable in the preceding plan and 
r , :.\;tions, and to adopt them in case of their being unanimous for 
the adoption : subject^ nevertheless, to the approbation of the Lord 
High Admiral, or the Commissioners fur executing the office of the 
Lord Hierh Admiral. 



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APPENDIX. 



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RECOMMENDATIONS x^ND SUGGESTIONS. 




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The Founder, with all deference to the high profesiiunal authorities 
who arc to adjudge the Medals, begs to suggest and reeommend as 

follows : 

i 

L That a book be kept in the custody of the Medical Commis- 
sioners of the Royal Navy, wherein is to be transcribed the plan and 
regulations, and to serve also as a record of the periodical adjn.diea* 
tionsj and wherein not oiily the naaies of the successful candidates 
may be inscribed, but also of all those of the first selection : amon^ 
whom it cannot be doubted that there will be found tokens of mt^It 
which may go without their due reward, from the limited number cf 
Medals, and ail of whom will, of course, possess a considerable share 
of merit above the unselected, and be deserving of consideratioii, 

2. That there be transcribed into this book of record such remarks 
as may have arisen out of the examinations, deliberations, and dis- 
cussions of those appointed to adjudge the Medals, and wiuch may 
prove a source of much valuable information not only for the Interests 



of the Nav\, 



7^ but of the community at large, while it will open a 



source of lib-ml and useful intercourse between the member? f 'I.o 
diiFerent public professional institutions of the empire, provij,/ ■.>- 
degree of publicity should be given to them. 



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THE END. 



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No Edition qf Lord Byron; s Worhs can 06 complete, unUss it i^ published 

by Mr Murray, as he alowposi.... ^ the Copyright, 



KOW READYj THE FOLLOWING COPYRIGHT EDITIOKSi OF 

LCD BYRON^S LIFE AND WORKS. 



I. 



BYRON'S LIFE AND POEMS- 

LiBRAEY Edition. Plates, 17 vols. Fcap. 8vo. GHs. 



II, 



BYRON'S LIFE AND POETRY. 

Portraits and Vignettes. 2 vols, Koyal 8vo. 15s. e&cli 



III. 



BYRON'S POETICAL WORKS 

Vignettes. 10 vols. 24mo. 265. 



■y.- 



BYRON'S OHILDB HAROLD. 

With Portrait and Sixty Vignette Engr*vings. 8vo. 21« 



BYRON'S CHILDB HAROLD 

Vienette, 24ino. 2s. Qd. 



VI. 




V 



T 

X 




'S TALES. 

2 vols, 24230. 5s 



VII. 



BYRON'S DRAMAS. 

Viijiiettes. 2 vol«. 24mo. 6s. 



Till. 



BYRON'S MISCELLANIES 



Viguettes. 3 vols, 24ino. 7s. 6d. 



IX. 



BYRON'S DON JUAN 

Vigaettae. 2 vols. 24mo. 5s. 



JOHN MURRAY, ALBEMARLE STREET. 



/ 



.ido^ 'i-'; ,eu^ 



.I'jin 



(fit'- 



*'- 



100 Pj 

,hort nobce, "1=^ 

:arietyofmiB- 

Persons com. 



Twenty aifeeni 
Salt. Price i 



s^ 



fif r varieties, i 

Whitney's tra 
Mineralogy. 

Chemical App 
Blowpipe, A^ 
^Yire ..mi Fo: 
porating Cap 
precipitating 
Crucible, Toi 
&c., fitted in 



TOiUfALJNE, 

Light. 



a 



S( 



Miscroscopii 
&c,, &c. 

^lODELS of th 

"^Veiglit and 
Models of Cr 



i'olisMng, 



A complete i 
"^^ te supplied 









*ato 



tile s 



stud 



149 



^■^RAAJ 



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av 



VO 






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[ES. 



l^iMERALOGY. 



A? it is impossible to acqaL^ a piacLIcal h ledge of Mikekalogt without the 
aid of specimens to '''^:-''''"':te the study, J. le; .xiit, Miaern^^^^lst to Her M-riestyj 
arranges a series, coii^istiug of Metals, Earths, and KockSj in u CABiNEr; -^^\h 
Catalogue, iTom T\'.o to One Hunuxed Guineas each, in the following proportion: 






100 Smal] S:: ^^nens of Metals,, Eart,hs. and Rocks, 
100 Ditto, with Bio\\^ipe, Magnet, Tuhes, Forceps, 

Borax, ond Box of Fragments for Experim 
200 Varieties, larger, with Descriptive Cataioguej 
800 Ditto, kx^ji and more select, with ditto, 
400 Ditto, ditto, 




L'* 



3 







2 12 



9* 

5 



10 10 

2i 



G 









e 



J. T., hamg recently purchased several lai-ge collections, and having extensiv 
connections in the mining districts of England and in foreign countries, can, at a 
short rii^tice, make up collections to any extent ; and is enabled to supply almost every 
variety of mineral. 

Persons commencing the study of Mineralogy, Conchology, or Geology, can be 
furnished with a great variety of specimens, carcfiiUy labelled, at %d> or 1^. each, 

FRAGMENTS FOIl ESPERIMEr^TS WITH BLOWPIPE. 



7. - 



lenty different Minerals named. 
Salt. Price 3^. 



Borax, and Microcosraic 



Fifty varieties, including the Emerald, Zircon, Platina, &c. lO^*. 

Whitney's translation of Berzelius on the use of the Blowpipe in Chemistry and 
Mineralogv. Price 9^. 



s 



Chemical Apparatus, for the Examination of Minerals, containing improved Bras 
Blowjnpe, Agate Mortal', Electrometer, Magnetic Needle, Platina Spoon-Forceps, 
Wire and Foil, Spirit Lamp, W^ax CandlC; Charcoal, Magnet, Brass Forceps, Eva- 
porating Capsule Glasses and Frame ; Knife, Forceps, and File ; Metallic Rods for 
precipitating Metals; Glass Tubes, Litmus Paper, Magnifying Glass, Hammer, 
Crucible, Touchstone, and Minerals for Experim.ents ; also, Tests, Acips, Fxuxes, 



&c., fitted in case, price 




0. 05, 




in 




^ 

TouiiMALiNE, Iceland Spar, Arragonite Selenite, &c., for E^; 

Light. 

Miscroscopic sections of Flint, Agate, Limestones, Fossil, and recent Teeth, "Wood, 
&c., &c. 

Models uf the most celebrated Diamonds in Europe, ^= ith a Description of their 
"Weight and Value. 



Models of Crystals, to illustrate Crystallography. 



Amateur Lapidary's Guide, by J. Maw^e, containing Instructions for Cutting, 
Polishing, and Slitting Hard Stones of every Description. Price 1^. 

A complete set of the Second Series of the Transactions of the Geological Society 
can be supplied at- half the published price. 



A new edition of the Geological Map of the British Isles, constructed by Professor 
Phillips, engraved by J. W. Lowry, is lately published. 



of 



f" 



Mr. TENNANT gives Private Instruction in Mineralogy, with a view to facili^ 
tate the study of Gr--,oaY, and of the application of Mineral substances fo the 
ArU illustrated bv an extensive Collection of Snecimens, Models, &c. 

149, Strand, Aprils 1848. 



Reeve. Eeuham, & Reeve, Printers, Sing WiUiam Street, Strand. 




FOR SCIENTIFIC X PROVINCIAL MUSEUMS. 

FoTiRTEKN Moi>Ei,Sj carefujlv coloured from the origmals, of Teeth and Bones of the 
Iguanodon, Ilylceosmmis, and Gavcai, discovered by Dr. Mantell, in the strata of 
Tilgate Forest, and now prcseived in the British Museum {Natv ;•' al IRsto'nj , North 
Gollery, Moow, IIL, Case— Eeptiles) , Frice of ike : v ,■ .: :Ue, lL2s,&d, 

The ahove are described in Wonders of GeoLgy, by Dr. Mantell. 

Cast of head of Crocodilufc Spenceri, from Isle of Sheppey; Figured in Bridgsvater 
Treatise by Dr. Buck^^ d, Plate 25'. Piiee 5^. 




and a half wide, of the remains of the IcUliyosaun, and Flesiosauri, from the 
Lias of Somerset^ &c., may be obtained from Mr. Tennant, 149, Strand, who is 

a series of label 



prepann^ a series oi laoeis, so that each plate may be referred to tlie original 
specimens in the cases of the British Museum. Price 21,?.; published at 50i\ 
The plates will be found useful to schoolmasters and others teaching Geology. Au 
excellent descrix)tion of the peculiar chai^acters of the fossils will be found in the 
Bridgwater Treatise by Dr. Buckland. 



^-i*V 



Saurian 



PLESIOSAURUS DOl!CHODE!RUS. 



The original Specimen of the unique Skeleton of this species of Plesiosaurus, no , 
in the British Museum, was obtained from the Lias, near Glastonbury, and is de- 
scribed and figured in the Bridgwater Treatise by Dr. Buckland (vol. ii. pL 17). 

I'he Cast, mounted on a strong Wood Frame, measuring 6ft. Sin. in length, by 
3 ft. 4 in. in width, is well adapted for Scientific and Provincial Museums, as exhibit- 
ing the remarkable characters and peculiarity of structure of this singular Keptile. 

{Frice of the Cast, U) 



-J 



DEDICATED TO THE REV. WM. BUCKLAND, D.D., F.E.S., & L.S., 

PROFESSOR OF GEOLOGY AND MINERALOGY IN THE UNIVERSITY OF OXFORD. 

These Models are constructed of various kinds of Wood, fitted together from 
actual Measurements of the Strata in tiic Coal and Lead Mining Districts of tk 
North of England. The upper part of each Model represents the surface of the 
ground ; the sides exhibit four vertical sections, each of which corresponds wth the 
sections usually drawn in Geological Works, and the base of each Model represents a 
horizontal plane at a certain depth under the s-u^face, according to scale. 

To sindents in Geolog}^, and others interested in Mineral Districts, these Models 
afibrd a clearer idea of Geological Phenomena than ordinary plans and sections, pre- 
senting a fac-sim.ile of the objects represented, which can be studied in every variety 
of position, and thus exhibit and explain the subterranean, as well as surface relations 
of the various Strata, Beds of Coal, and Mineral Veins. 




-■"^ 



cession oi . „ _ 

Districts : the eifeets produced by Faults or Dislocations ; Intersections of Minerel 

Veins. &c. ; and ai-e accompanied with a letter-press description, 

By T, SOPWITH, Esq., F.G.S., 

Memb. la^t. C.E., Author of a Treatise od Isometrical Drawing, &c. 

Sold in Cases, bound and lettered to resemble large octavo, quarto, or folio volumt;-. 

By J. Tekkant, Geologist, ^c, 149, Strand, London. 

Set of Six 3fodels, 3 inches square, £2 : 2 

Smne, 4 inches square, 2 . 10 

Twelve Models ^ -^ inches souare. 4 : 



Same, 



b mches squai'e, 
4 inches square, 



'J 







It may be proper to observe, that the train of investigation which is required to 
study these Models is wholly apart from the theoretical researches which extend to 
the original formation of th(^ rocks^ and is confined to such facts as are open to every 
day observation, and of which no doubt can possibly exist. 

The description of the Models can be had separate, price 1^-. M. 







« 



i 



I 



•I 



can t"^ A 
A Collect;'^' 

jJative mi 
Metallic Ores 

Rocks; Gr 

Limestones, r 



SliUBlAN 



1 



SECONCAli'^ 

Cretaceous Gr 

Tertiary . 



A Stratigra 
of the Bntish 

by J. Tenna? 



J. Texnan' 

Shells, begs t( 
ably reduced i 

COLLECTIO 

according to t 
Tkefolloi/ymg 

w -^ 

n'ODARCH's ] 

fte Characi 
li^au Arrai 
wMch is ad 
plates, 6^. 

Ol>ser^'atio] 




^4 ?^^?^ 



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.w«« lluseums. "^ 



GEOLOGY. 

Pfksons wishing to become acquainted witli thds iiiterestiiig branch of Science 
will find their studies greatly facDitated by means of eleru.utary collections, which 
can be had at Two, five, Ten, Twenty, or Mfty Guineas each. 

Arranged by J. Tennant, Geologist, 149, Sinmd, London. 

A Collection for Five Guineas, v^hich will illustrate the recent works on Geologv, 
coutains 200 specimens, in a MaJiogany Cabinet, with five trays : \dz. 

MiNEKALS which are either the components of Rocks, or occasionally embedded in 
them :— ftiiartz, Agate, Chalcedony, Ja^^pen Garnet, Zeolite, Hornblende, Augite, 
Asbestus, Felspar, Mica, Tde, Tourmaline, Calcareous Spar, Fluor, Seleaite^ Barvta, 
Strontia, Salt, Sulphur^ Plumbago, Bitumen, &c., &c. 

Native Metals, or METALLiFEnous Minerals; these are found in masses or 

beds, in veins, and occasionally in the beds of rivers. Specimens of the following 
Metallic Ores are put in the Cabinet:— Iron, Manganese, Lead, Tin, Zinc, Copper, 
Antimony, Silver, Gold, Platina, ^c. 

EocKS ; Granite, Gneiss, Mica-slate3 Clay-slate, Porphyry, Serpentine, Sandstones, 
Limestones, Basalt, Lavas, &c. 

Silurian Fossils from the Llandeilo, Wenlock, and Ludlow Rockse 

Secondary Fossils from the Devonian, Carboniferous, Lias, Oolite, Wealdcn, and 
Cretaceous Groups. 

Tertiary Fossils from the Plastic-clay, London-clay, Crag, &c. 



H UL 



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1^ 



JUST PUBLISHED. 



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A Stratigraphical List of British Fossils i arranged under the principal divisions 
of the British strata, with a few elementary remarks on their character and localities, 
by J. Tennant, F.G.S., price 2^, Sd. Can be sent by post for sixpence extra. 



^ 
^ 



CONCHOLOGY. 

J. Tennant, having purchased the late Mrs. Mawe's extensive Collection of recent 
Shells, begs to inform Collectors that the specimens are all re-marked, and consider- 
ably reduced in price. 

Collections shewing the Genera, from Two to Twenty Guineas and upwards, 
according to the number and qaality of the Specimens, 

The following Works on Conchology, ■published by the late Mr. Mmve, will h 

found useful to beginners ; they are all reduced in price, 

AVoDARCii's introduction to the Study or Conchology, 4th edition, describing 
the Character of the Orders, Genera, and Species of Shells, according to the Lin- 
necau An-angemcnt ; with an extensive Catalogue of Names under each Genus, to 
which is added the best mode of Collecting, Cleaning, and Preserving Shells. Seven 
plates, 6<y. plain ; or 10«y. coloxu'ed. Elegantly bound, 13,5. ^d. 

An Epitome of Lamarck's Arrangement of Testacea^ with Illustrative 
Observations. Bv C. Du Bois., F.L.S. Price 10^. 

An Illustrated Introduction to Lamarck's CoNciioLoaY; being a literal 

Translation of the Descriptions of the recent and Fossil Genera, accompanied by 
twenty-tvv'o highly -finished Lithographic Plates. By E, A. Crouch, F.L.S. Price, 
coloured, 2/. Plain, 20,?. 

Mawe's Shell Collector's Pilot, or Voyager's Companion, with a coloured 
Frontispiece and Plates of Insects. This Work is particularly adapted for voyagers 
in general, pointing out the places where the best shells were obtained during a 
voyage of discovery round the world ; also the best methods of preserving Insects, 
Birds, &c. 4th edition, 3^. 



An extensive assortment of Minerals, Shells, and Fossils, together with all the 
recent Works relating to Minf.ralogy, Geology, Conchology, and Chemistry, 
Geological Maps, Hammers, Blowpipes, and Acid Bottles &c., can be supplied by 

JAMES TENNANT, Mineralogist to Her Majesty, 149, Strand, Loadon. 



♦ I ' * 



JAMES TENNANT, 

1^0, Stimnp (three doors west of Somerset House), London", 



^ 



""•R THE 






DRAWING -I 




LIBRARY, AND DINING-ROOM; 



coinSisting oy 



^^ 



-■^ 



i 



1*^ 



ITALIAN ALABASTERS. 

r 

A superior assortment of Gwnps aad iugurns made expressly for J. T., and exad 
copies of the Adrian. Medicean, Borghcse, and >¥=> ick Vases ; Models ot the 
Leaning Tower, Baptistery, and Cathedral at Pisa ; Trajan's PiUar, Scipio's Tomb, 
and a great variety of smaller Articles. 

Glass Shades of all sizes and dimensions for Alabaster and other delicate Ornament.. 

BLACK MARBLE & DERBYSHIRE SPAR-OkMAMENTS. 

Of these a large assortment is alwavs kept on Iiand, of the finest quality, mand'ac- 
tiired into Chess and Drawing-room Tables, Library Inkstands, \\ atcb stands bar- 
cophagi. Candlesticks. Spell-holders, Tripods, and a great variety ol Vases, 
engraved and inlaid, ehicfly copied from the antique. 

Correct copies of Bankes's Obelisk with Greek Inscription; the Obelisks at Helio- 
polis and at Zan, 

MAEBtE Paper-weights and Pen-holders. 



THE ROifiAN AND FLORENTINE MOSAICS 



Have been successfully imitated in Derbyshire, 
stands, Paper- ^veights, Brooches, Crosses, and 
execution to the Italian, 



The Tables, Vases, 
Necklaces, are equal 



Boxes, Ring- 
in design and 



MISCELLANEOUS. 



Copies of Danneker's Statue of Ariadne. The Portland Vase, and other Ornan..ui3 
in Bisque China. 



Art 



Mavmfactuxcs. An assortment is constantly kept, including 
I)orotJie%, IJ-fia and the lion, Infant Neptune, &c. 
Models of Ponts, Cros:=es, &c., described by the Cambridge Camden Soci ■;;. 
u=ts of Her Majesty, Prince Albert, Wellington, Nelson, Scott, Byron, and others. 
These can also be had in white compositiou with glae-. shades, from 14- to 30^-. 



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An experienced artist is employed to model. Busts from life, of a small size, can m 



to Pive guixicas each. 



executed in white composition, from Three 
Tablets and Monuments can Lo executed to order. 
Models of Sporting Dogs, Cattle, &c., carved in Derby ?.hh'e. 
i^HATOYANT Gypsum NECiilACEs, EaT-drops, Crosses, and Brooches. 

ITALIAN, FRENCH, AND ENGLISH BRONZES. 

An assortment of Yases, Candl-^icks, Inkstands, Figures, Lotter-weigMs, &c. 



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Mr. 1^..!^ ANT having Agents in Pi^jce, Italy, and Germany, is supplied with 

every No';:Uy coanceted -with his Business. 



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Riley Dunn & Wilson 

CONSERVATORS a BOOKBINDERS 



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