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?K/1 



THE CHEMICAL NEWS, January io, 1896, 



THE 

CHEMICAL NEWS 



AMD 



JOURNAL OF PHYSICAL SCIENCE. 

WITH WHICH It INCORPOKATBD THB **CHBMICAt. OASBTTB." 

% |0ttrnal af ^tactual C^tmbtrj; 

IN ALL ITS APPLICATIONS TO 

PHARMACY, ARTS, AND MANUFACTURES. 



\a^ 



BOITBO BY 

WILLIAM CROOKES, F.R.S., &c. 



VOLUMB LXXII^iStfj. 



LONDON: 
PUBLISHED AT THE OFFICE, BOY COURT, LUDGATE HILL, B.C. 

AND SOLD BY ALL BOOKSBLLBRS. 

MPCCOXCV. 



IObuiicalNsw*, 
I Jaa. 10,1896. 



hf NE«A' York] 



/public 



i^RARY/ 



49186 






^on ,^ 



'^ 









LONDON: 

k>ltINTtD BY EDWIN JOHN DAVBYt 

BOY COUIIT9 LUDOATB HILL, B.C 






THE CHEMICAL NEWS. 



VOLUME LXXII. 



EDITED BY WILLIAM CROOKBS, F.R.S., &c. 



No. 1858.— JULY 5, 1895. 



NEW COMBINATION OF ARGON: SYNTHESIS 

AND ANALYSIS. 

By M. BBRTHELOT. 

Thi knowledge of the a^on of carbon disulphide upon 
nitrogen when submitted to the eledric effluve led me to 
try the same influence upon argon. The experiment has 
been fully successful ; it gives nse to a combination more 
rapid and complete than that produced with benzene, and 
not apparently limited like that of phenomena of equili- 
brium. In each case the mercury intervenes chemically, 
as I have recognised in my recent experiments. 

I operated upon 6*55 c.c. of argon, as pure as possible, 
and such that benzene, employed once, did not determine 
(under the influence of the effluve) a dired absorption 
exceeding nine-hundredths. I brought the gas into con- 
tad with liquid carbon disulphide at about 20**, a temper- 
ature at which the tension of the sulphide rises to 0*98 
metre. This fad has been taken account of. 

After three hours of the effluve, under the conditions 
described in case of nitrogen, the absorption of the argon 
rose to zx per cent of its initial volume. After eight hours 
it increased to 17 per cent. 

The gases of the recipient were changed, and a new 
dose of carbon disulphide was added. 

A third readion of the effluve raised the absorption to 
aa per cent ; a fourth readion to 34 per cent ; and a fifth 
readion to 39 per cent. 

The gases of the recipient were changed again ; a fur- 
ther dose of carbon disulphide was added, and the experi- 
ment was resumed. The total absorption increased then 
to 56 per cent. The argon represented only 2*9 c,c. An 
accident prevented me from prolonging this experiment, 
which had lasted about sixty hours. 

But it is scarcely doubtful but that it would have ended 
in total absorption. It did not appear limited by an in- 
verse readion, and it is not accompanied at the ordinary 
pressure by a fluorescence visible in full daylight, and 
capable of giving rise in diffused light to special spedro- 
BCopic rays. 

These charaders distinguish the absorption of argon by 
carbon disulphide from its absorption by benzene. In fad, 
the latter is slower, and is limited by readions of dissoci- 
ation which stop the dired adion, effeded once, at about 
9 or zo per cent with pure argon. Indeed, on separating 
the unabsorbed argon from its produds, we mav renew the 
adion* but always with difficulty. After sixty hours, with 



renewal, I have not gone beyond 16 per cent. Lastly, the 
absonption of argon by benzene determines the formation 
of a fluorescent vapour, giving at atmospheric pressure a 
fine green, visible in full daylight, in which we distinguish 
among others the rays of the vapour of mercury, f.#., the 
indication of the presence of a volatile compound of 
mercury formed in the readion of argon with the nydroffen 
carbide. On the contrary, no fluorescence of this kind at 
this pressure is observed during the absorption of argon 
by carbon disulphide. 

I shall soon return anew to the study of this extraordi- 
nary fluorescence. But at present I may mention that it 
constitutes an essential difference between the combina- 
tion of argon with the elements of carbon disulphide and 
its combination with the elements of benzene. Nitrogen 
gives nothing analogous. 

I submitted the produd of the readion to a special ex- 
amination. The compound naturally contains mercury, 
but we cannot decide whether this element is associated 
with argon in one and the same compound. If treated 
with sodium sulphide it does not give readions analogous 
to those of sulphocyanide, except a slight yellow colour- 
ation (after acidification) with ferric salts. 

I have succeeded in regenerating argon from the com- 
pound just mentioned. In this new research I avoided 
taking the produd which had absorbed the first doses of 
the gas, as it might contain nitrogen if any remained in 
the argon used for the experiment. 

I operated upon the second produd, which had absorbed 
1*2 c.c. of argon ; I submitted this produd at once to the 
adion of heat, in the same tubes m which it had been 
condensed over the mercury after the complete evacuation 
of the gases, and operating as it had been done in case of 
carbon disulphide. 

Whilst this operation performed on the produd of the 
absorption of nitrogen by carbon disulphide yielded only 
an insignificant residue, with the produd of argon I ob- 
tained o'6a c.c, !.#., equal to about half the volume of 
the gas absorbed. This number, however, is too low, 
considering that a very considerable part of the condensed 
produd escapes the adion of heat, because of the impos- 
sibility of causing the mercury to boil as far as the lower 
and expanded part of the test-tubes, whereby a portion of 
the transformed matter is deposited. The contraded 

Eart alone is raised to about 500**. Thus the figures given 
ave a merely qualitative meaning, being intended to give 
some idea of the order of greatness of the phenomena. 
I will add that I have caused the condensed produd, in 



Preparation and Properties of Pure Melted Molybdenum. {'^']niy5^i%^"' 



the annular intervals of the two tubes, to undergo three 
successive heatings to dull redness, evacuating each time 
the gases produced and coUeaing them again separately. 
Their gross volume amounted to several c.c. by reason of 
the regeneration of the carbon disulphide, a circumstance 
which ensures the most complete elimination of the other 
gases. 

The first heating yielded, after the readion of the alco- 
bolised potassa and acid cuprous chloride, and final purifi- 
cation by potassa, volume « 0*41 c.c; the second heating, 
0*20 c.c. ; the third heating, o*ox c.c. 

The decomposition of heat is thus exhausted in the 
portion of the substance capable of being heated to dull 
redness. 

To verify if the gas thus regenerated is really argon, I 
had recourse to the only positive charaAer obtainable in 
my apparatus, f.#., the produdion of the fluorescent 
spedrum developed by benzene at the ordinary pressure. 
I used effluve-tnbes of reduced dimensions, such that 0*40 
c.c. of the regenerated gts occupied in the first place a 
length of 5 or 6 cm. Bv operating thus I succeeded, in 
fad, in obtaining most distmdiy, at a pressure bordering 
upon that of the atmosphere, the green fluorescence cha- 
raderistic of the compound of argon and benzene. The 
OH^y c.c. were reduced thus in eight hours to 0*35 c.c, the 
absorption taking place with the slowness charaderistic of 
argon, and reaching the same limit. I repeated the same 
test with 0*12 c.c. of the gas regenerated by the second 
heating with the same success, and I established in both 
cases the existence of the specific rays of this fluores- 
cence, developed in diffused light and near the normal 
pressure. 

This experiment seems to me capital, since it demon- 
strates that argon can enter into combination and be 
regenerated with its original properties. — Comftes Rendus, 
cxx., p. 1316. 



PREPARATION AND PROPERTIES OF 

PURE MELTED MOLYBDENUM, 

By UBNRI MOISSAN. 

IR a former paper we have shown that it is easy to pro- 
duce cast molybdenum, by heating in the eledric furnace 
a mixture of charcoal and of the oxides of this metal. 
We shall now give the continuation of our researches on 
this question. , ^ , , . ^ . ^ 

We must first mention that molybdenum, which is ob- 
tained in a pulverulent state by the redudion of the 
binoxide in hydrogen, was fused by Dcbray before the 
blowpipe only in the form of small globules containing 4 
to 5 per cent of carbon. 

To prepare molybdenam we set out from pure ammo- 
nium molybdate, reduced to powder and placed in a crucible 
of refradory earth. No. Z2, capable of containing i kilo. 
The crucible, covered with its lid, is heated for one and a 
half hours in a Perrot furnace. After cooline, the oxide 
is a dense powder of a violet-grey, corresponding to the 
formula M0O2. One heating yields from 760 to 770 grms. 
of oxide. This oxide was mixed with sugar-charcoal, in 
powder, in the following proportions :— 

Oxide 300 grms. 

Charcoal •• .. 30 » 

In this mixture the oxide is in decided excess compared 
with the charcoal. The powJer is heaped up in a crucible 
of coke and submitted to the adion of an arc produced by 
a current of 800 amperes and 60 volts for six minutes. 
We must avoid the complete fusion of the metal, so as to 
leave a solid layer in contad with the crucible which 
would be strongly attacked by the liquid molybdenum. 
Under these conditions we obtain a metal perfedly pure 
and free from carbon ; it is easy in one hour to prepare 
more than i kilo. 



If this preparation lasts more than six minutes, the 
molybdenum obtained is liquefied, corrodes the crucible, 
becomes carburetted, and we obtain a grey cast metal, 
very hard and brittle. 

Cast Molybdenum, 
This cast metal has a specific gravity of 8*6 to 8*9, 
according to its proportion of carbon. When satu- 
rated with carbon it is much more fusible than molyb- 
denum. When rich in carbon it is grey and brittle ; at 
i2'5 per cent of carbon it becomes white, and can be 
broken up upon the anvil only with difficulty. It presents 
all the charaderistics of the molybdenum studied by 
Debray. It rapidly dissolves carbon, and abandons it on 
cooling in the state of graphite, precisely as does cast- 
iron. Nevertheless, when saturated with carbon it yields 
a carbide, crystallised in fine needles. Grey cast-molyb- 
denum is very hard ; it scratches steel and quarts. When 
melted, it becomes a very mobile liquid, which can be 
poured whilst giving bright sparks and abundant fumes of 
molybdic acid. We have been able to melt and cast 
ingots of from 8 to 10 kilos. These castings had the fol- 
lowing compositions : — 

White. Grey. 

Molybdenum •• .. 95'83 92*46 

Combined carbon.. 3*04, 319, 254 4*90, 5*50 

Graphite.. .. •• 0*00 0*00,171 

Slags 0*74,0*53,0*62 — — 

Molybdenum Carbide* 

This compound is prepared by heating in the eledric 
furnace molybdenum binoxide with an excess of charcoal. 
The best proportions are : —Binoxide, 250 grms. ; charcoal, 
50 grms. The duration of the heating is from eight to 
ten minutes with a current of 800 amperes and 50 volts. 
If we use an excess of charcoal it is found in the mass in 
the state of graphite. 

The regulus obtained is of a brilliant white and has a 
crystalline fradure ; it splits readily. It is readily crushed 
on the anvil, and we may separate from it small elongated 
prisms of a distind crystallisation. Its specific gravKy 
is 8'9, and its composition is MojC. 

Analysis^ 
In the various specimens described in this memoir, the 
molybdenum, after treatment with nitric acid, has been 
precipitated as mercurous molybdate, and finally deter- 
mined as bioxide. When the carbide contains no graphite, 
the carbon was separated by pure dry chlorine, and then 
determined by combustion in oxygen, according to the 
weight of carbonic acid coUeded. According to this 
method, the portions of carbon are always rather low. 
We have obtained the following figures :— 

Theory for 
Mo,C. 

Molybdenum . .. 93*82 — — . 94x2 

Combined carbon . 5 62 5*53 5*48 5*88 

Graphite — — — — 

Slags 0*17 

9961 

If the carbide contains graphite it is attacked in a flat* 
bottomed flask traversed by a current of oxygen. The 
gases evolved pass into a tube filled with copper oxide, 
the watery vapour is retained in a tube filled with sul- 
phated pumice, and the carbonic acid is fixed in potassa. 
The increase of the weight of the potassa tube shows the 
carbonic acid, and, consequently, the carbon. The acid 
liquid of the flask, after filtration and washing, shows the 
graphite, and the molybdenum is next determined by 
mercurous nitrate. This novel method gave as results : — 

9. xo. 

Molybdenum .. •• •• •• 92*60 9i'90 

Combined carbon .. •• •• 5*15 5*45 

Graphite • •. 1*61 i*^ 



*^"r5?«89'r*'} Prepare n and Properties of Pure Melted Molybdenum. 



On taking account of the graphite and calculating the 
proportion o( molybdenum to the carbon we find :~ 

9. 10. Theory Mo,C* 

Molybdenum 94*45 94'xo 94*^2 

Combined carbon •• .. 5*55 5*90 5-88 

Pure Fused Molybdenum. 

Pure molybdenum has a specific gravity of 9*01. It is 
a metal as malleable as iron. It can be easily filed and 
polished, and forged hot. It does not scratch either 
quartz or glass. When free from carbon and silicon, it 
scarcely oxidises in the air below a dull redness. It may 
be kept for several days unchanged in water, whether or- 
dinary or charged with carbonic acid. In presence of air 
below dull redness, it is covered with an iridescent film, 
as is steel. About 600° it begins to be oxidised, and 
yields molybdic acid, which is slowly volatilised. 

A fragment of molybdenum heated for some hours in a 
sloping porcelain tube over an analytical furnace yields, 
in the upper part of the tube, a felted mass of crystals of 
molybdic acid. The metal is not covered with any other 
oxide, and finally disappears, leaving a fine crystallisation 
of molybdic acid. If heated before the gas-blowpipe, a 
fragment of molybdenum emits vapours in considerable 
quantity. If heated before the oxyhydrogen blowpipe, it 
burns without melting, giving off abundant fumes of mo- 
lybdic acid and leaving a blue oxide, sparingly fusible. If 
heated in a current of pure oxygen, it takes fire between 
500" and 600* ; and if the current is rapid the combustion 
may continue without the intervention of any extraneous 
source of heat. 

This combustion ensues with intense incandescence, 
and may serve as a fine ledure experiment. 

Melting potassium chlorate attacks molybdenum with 
violence. The chlorate is melted, and a fragment of mo- 
lybdenum thrown upon its surface, when it becomes in- 
candescent and revolves upon the surface of the liquid. 

The temperature of the reaAion rises rapidly, the 
molybdenum burns with flame, and there escape abundant 
white fumes of molybdic acid, which remain suspended in 
the air in the form of white floating filaments. Some- 
times the fragment of molybdenum is raised to a tempera- 
ture high enough to perforate the side of the capsule, 
which is melted in contadl with the metal. 

Melting potassium nitrate under similar conditions 
yields a readiion similar, though less violent, with forma- 
tion of an alkaline molybdate. 

A mixture of molybdenum and lead peroxide heated in 
a test-tube produces a great liberation of heat and light. 

Sul(^ur has no adion at 440*, but hydrogen sulphide 
at 1200'' transforms molybdenum into a bluish grey 
sulphide, amorphous, having the properties of molyb- 
denite, and leaving, on friaion, a black mark upon paper. 

Fluorine does not attack molybdenum in fragments, but 
if the metal is coarsely powdered, there is formed, without 
incandescence, a volatile fluoride. 

Chlorine attacks molybdenum at dull redness, but with- 
out incandescence. With bromine, the adion takes place 
at a cherry- red heat, but without great intensity. 

Iodine has no adion at the temperature of softening 
glass. 

Silver, zinc, and lead fluorides are decomposed, but 
without the formation of volatile fluorides. 

Phosphorus perchloride, if slightly heated, readily at- 
tacks molybdenum, forming a volatile chloride, which is 
easily modified in presence of atmospheric moisture, 
taking a fine blue colouration. 

This readion is produced with most of the compounds 
of metallic molybdenum — the oxides, the sulphide, 
molybdic acid, and the molybdates. It may serve for the 
rapid detedion of metallic molybdenum or its compounds. 
It is effeded in the following manner ;— 

Into a small test-tube we put a fragment of the sub- 
stance in question, adding a little phosphorus perchloride, 
and heating gently. There are formed reddish fumes of 
molybdenum chloride and oxychloride which condense in 



a brown ring more or less intense. If the quantity of 
molybdenum is very slight, the ring tnay be scarcely 
visible. It will then be sufficient to expose it to moisture 
to see it take an intense blue tint, due to the formation of 
hydrated chloride. 

The adion of hydracids upon pure molybdenum is 
almost similar to that which they exert upon cast molyb- 
denum. These experiments, however, have been described 
by different observers, Bucholz, Berzelius, and Debray. 
We merely mention that hydrofluoric acid does not attack 
it, but on adding a drop of nitric acid the adion sets in 
and continues with energy. In presence of a mixture of 
equal parts of the two acids the solution is complete, and 
there remains a rose-coloured liquid which, with ferro- 
cyanide, gives an intense red-brown colour, but no pre- 
cipitate. The mass some hours afterwards coagulates to 
a jelly. 

In a current of nitrogen at 1200^ molybdenum, whether 
in fragments or in powder, does not form a nitride. 

It does not combine with phosphorus at the tempera- 
ture of melting glass. 

Boron combines with molybdenum at the temperature 
of the eledric furnace, yielding an iron-grey melted mass 
containing cavities lined with prismatic needles. 

Under the same conditions, silicon yields a crystalline 
silicide not fusible before the oxyhydrogen blowpipe. 

The adion of carbon deserves to arrest our attention for 
a few moments. 

Pure molybdenum, as above described, is a soft metal, 
which is easily filed and which does not even scratch 
glass. If we heat a fragment of molybdenum for some 
hours to a temperature close on isoo** in the midst of a 
mass of charcoal in powder, it becomes cemented, takes 
up a small quantity of carbon, and its hardness increases 
so that it can scratch glass. If we then heat it to 300° 
and plunge it suddenly into cold water, it is tempered, 
becomes brittle, and hard enough to scratch rock costal. 

Inversely, if we take cast molybdenum containing 4 per 
cent of carbon, very hard and brittle, and heat a fragment 
for some hours with molybdenum binoxide in a lined cru- 
cible, it becomes refined, and its surface may then be 
readily filed and polished. 

I attribute this decarburation of the solid cast molyb- 
denum at a temperature very remote from its melting, 
point to the ready diffusion of vapours of molybdic acid 
through the metal. I consider that these properties may 
find applications in metallurgy. 

If, in a metal saturated with oxygen, such as is ob- 
tained in the first period in the Bessemer converter, 
we wish to remove this oxygen, we add manganese, 
which is oxidised more easily than iron, and then 
passes into the slag (Troost and Hautefeuille). It has 
been also proposed to employ aluminium, which has givea 
good results, because it is combustible, i.^., because it 
seizes on the oxygen, but which has the inconvenience of 
producing solid alumina. I think that molybdenum may 
be used under the same conditions; it would have the 
advantage — 

z. Of yielding a volatile oxide, molybdic acid, which 
would be liberated immediately in the gaseous statOi 
stirring up the whole mass. 

2. Used in a slight excess it would leave in the bath a 
metal as malleable as iron, and capable of being tempered 
along with the latter. 

The powder of molybdenum, which it has been 
attempted to use already, cannot render the same services, 
because it burns rapidly upon the surface of the bath in 
contad with the air without having yielded any useful 
effed. 

Analysis of Pun Molybdenum, 

II. xa. 13. 14. 

Molybdenum .. 99*98 99'37 99*89 99*78 
Carbon .. .. 0*00 o*ox 0*00 0*00 

Slag 0T3 0*28 o*o8 o'i7 

-^Comptfs Rendus, cxx., p. 1320. 



New Gas obtained jrom Uraninite. 



f CBIMI^At NlWt, 

1 Jttiy 5i X895. 



ON THB 

NEW GAS OBTAINED FROM URANINITE.* 
(Fifth Note). 

By J. KORMAN LOCKYBR, C.B., F.R.S. 

Ik a former commuoication I pointed out the spedro^ 
Bcopic evidence, famished by the isolation of lines in 
certain minerals, which indicates that the complete 
speArnm obtained when brdggerite is submitted to the 
distillation method is produced by a mixture of gases. 

In order to test this view, I have recently made some 
observations, based on the following considerations :— 

I. In a simple gas like hydrogen, when the tension of 
^e eledric current given by an indudion coil is increased, 
by inserting first a jar, and then an air-break into the circuit, 
the effed is to increase the brilliancy and the breadth of 
aU the lines, the brilliancy and breadth being greatest 
when 4he longest air-break is used. 
' a. Contrariwise, when we are dealing with a known 
compound gas; at the lowest tension we may get the 
coinplete spedrum of the compound without any trace 
of its constituents, and we may then, by increasing the 
tension, gradually bring in the lines of the constituents, 
until, when complete dissociation is finally reached, the 
spedmm of the compound itself disappears. 



The unequal behaviour of the lines has been further 
noted in another experiment, in which the produds of 
.distillation of brdggerite were observed in a vacuum tube 
and photographed at various stages. After the first heat- 
ing, D3 and 447Z were seen bright, before any lines other 
than those of carbon and hydrogen made their appear- 
ance. With continued heating, 667, 50x6, and 492 also 
appeared, although there was no notable increase of 
brightness in the yellow line ; still further beating intro- 
duced additional lines 5048 and 6347. 

These changes are represented graphically in the follow* 
ing diagram (ng. a) :— 

It was recorded further that the jrellow line was at times 
dimmed, while the other lines were brightened. 

In my second note communicated to the Royal Society 
on the 8th instant, I stated that I had never once seen 
the lines recorded by Thal6n in the blue, at A 4932 and 

4715- 

It now seems possible that their absence from my pre- 
vious tubes was due to the fad that the heating of the 
minerals was not sufficiently prolonged to bring out the 
gases producing these lines. 

It is perhaps to the similar high complexity of the gas 
obtained from cliveite that the curious behaviour of a 
tube which Professor Ramsay was so good as to send me 
must be ascribed. When I received it from him, the 



*I7I' 


9875. 


c 

6565.667. 


1. 










:--ll 









FlQ. z. 

Diigram thowiog chtngei in inteniitiei of Hdm brought aboat by varying the tension of the 

■park. X. Without air-break, a. With air-break. 



.«7. 



Iflf.TO 
SOf 



6B70. 



694^ 



667. 



FlQ. a. 
Diagram showing order in which linei appear in tpeAmm of vaeuum tube when broggedte is heated. 



Working on these lines, the spedrum of the spark at 
atmospheric pressure, passing through the gas, or gases, 
distilled from brdggerite, has been studied with reference 
to the special lines C (hydrogen), D3, 667, and 447. 

The first result is that all the lines do not vary equally, 
as they should do if we were dealing with a simple gas. 

The second result is that at the lowest tension 667 is 
relatively more brilliant than the other lines ; on increas- 
ing the tension, C and D3 considerably increase their 
brilliancy, 667 relatively and absolutely becoming more 
feeble, while 447, seen easily as a narrow line at low ten- 
sion, is almost broadened out into invisibility as the ten- 
sion is increased in some of the tubes, or is greatly 
brightened as well as broadened in others (fig. x). 

The above observations were made with a battery of 
five Grove cells ; the redudion of cells from 5 to 2 made 
no difference in the phenomena except in reducing their 
brilliancy. 

Reasoning from the above observations, it seems evi- 
dent that the effed of the higher tension is to break up 
a compound, or compounds, of which C, D3, and 447 
represent constituent elements ; while, at the same time, 
it would appear that 667 represents a line of some com- 
pound which is simtiltaneously dissociated. 

* A Paper read before the Royai Society. 



glorious yellow effulgence of the capillary, while the cur- 
rent was passing, was a sight to see. But after this had 
gone on for some time, while the coincidence of the 
yellow line with D3 of the chromosphere was being in- 
quired into, the luminosity of the tube was considerably 
reduced, and the colours in the capillary and near the 
poles were changed* From the capillary there was but a 
feeble glimmer not of an orange tint, while the orange 
tint was now observed near the poles, the poles them- 
selves being obscured by a coating on the glass of brilliant 
metallic lustre. 

After attempting in vain for some time to determine the 
cause of the inversion of D3 and 447 in various photo- 
graphs I had obtained of the spedra of the produds of 
distillation of many minerals, it struck me that these re- 
sults might be associated with the phenomena exhibited 
by the tube, and that one explanation would be rendered 
more probable if it could be shown that the change in the 
illumination of the tube was due to the formation of 
platinum compounds, platinum poles being used. On 
Mayazst I accordingly passed the current and heated 
one of the poles, rapidly changing its diredion to assure 
the adion of the negative pole, when the capillary shortly 
gave a very strong spedrum of hydrogen, both lines and 
strodure. A gentle heat was continued for some time 
and apparently the pressure in the tube varied very con- 



CasnicALllBwrtl 

July 5. 1895. I 



Standard Acid Solutions. 



siderably, lor as it cooled the hydrogen disappeared and 
the D3 line ehone out with its pristine brilliancy. The 
experiment was repeated 00 May 24th and similar 
phenomena were observed. 



ON THE 

OCCLUSION OF OXYGEN AND HYDROGEN 

BY PLATINUM BLACK.* 

(Part L). 

By LUDWIG MONO. P.R.S., WILLIAM RAMSAY, 
VhD., F.R.Sn mod JOHN SHIELDS, D.Sc, Ph.D. 

The authors describe some preliminary experiments on 
the occlusion of oxygen and hydrogen by platinum spbnge 
and foil, which in general confirm the results obtained by 
Graham. At most only a few volumes of these gases are 
occluded by the more coherent forms of platinum. 

After giving details of what they consider the best 
method of preparation of platinum black, they next de- 
scribe some experiments which had for their objed the 
determination of the total quantity of water retained by 
platinum black, dried at 100* C.^and the amount of water 
which can be removed from platinum black at various 
temperatures in vacuo. As the result of these experi- 
ments they find that platinum black dned at 100* retains 
in general 0*5 per cent, of water, and this can only be re* 
moved in vacuo at a temperature (about 400**) at which 
the black no longer exists as such, but is converted at 
least partially into sponge. At any given temperature 
the water retained by platinum black seems to be con- 
stant. The density of platinum black dried at loo** C. is 
19*4, or allowing for the water retained by it at this tem- 
peratuie, 21*5. 

The amount of oxygen given off by platinum black at 
various temperatures was determined. Altogether it 
contains about xoo volumes of oxygen ; the oxygen begins 
to come off in quantity at about 3000 C. in vacuo, and 
the bulk of it can be extra€ked at 4000 C, but a red heat 
is necessary for its complete removal. Small quantities 
of carbon dioxide were also extraded, chiefly between 
100— 200PC. 

In determining the quantity of hydrosen occluded by 
platinum black the authors have carefully distinguished 
between the hydrogen which goes to form water with the 
oxygen always contained in platinum black, and that 
which is really absorbed by the platinum pir se. Alto- 
gether about 3x0 volumes of hydrogen are absorbed per 
unit volume of platinum black, but of this aoo volumes 
are converted into water, or only z zo volumes are really 
occluded by the platinum. Part of it can be again re- 
moved ;it the ordinary temperature in vacuo ; by far the 
larger portion can be extraAed at about 256^3000 C, but 
a red heat is necessary for its complete removal. The 
amount of hydrogen absorbed by platinum is very largely 
influenced by slight traces of impurity, pi'obably grease 
or other matter which forms a skin over the platinum. 

Platinum black in vacuo absorbs a certain quantity of 
hydrogen. On increasing the pressure of the hydrogen 
up to abont aoo— 300 m.m. a further quantity is absorbed, 
but after this pressure is almost without tHt€t, By in- 
creasing the pressure from one atmosphere up to four and 
a half atmospheres, only one additional volume of hydro- 
gen was absorbed. On placing platinum black charged 
ynih oxygen in an atmosphere of oxygen, and increasing 
the pressure to the same extent, eight and a half additional 
volumes were, however, absorbed. 

Platinum black charged with hydrogen and placed in an 
atmosphere of hydrogen kept approximately at atmo- 
spheric pressure, and platinum black charged with oxygen 
and confined in an atmosphere of oxygen behave quite 
difiierently when heated. In the former case hydrogen is 

* bstraA of a paper read before the Royal Society. 



immediately expelled on raising the temperature, whilst 
in the latter case oxygen is steadily absorbed until a tem- 
perature of about 36g^ C. (the temperature of maximtmi 
absorption) is reached, when, on further heating, oxygen 
begins to come off again. 

Incidentally it was noticed that mercury begins to com* 
bine with oxygen at 2370 C, and that a mixture of plati- 
num black and phosphorus pentoxide absorbs oscygen at 
a high temperature, probably with the formation of a 
phosphate or pyrophosphate. 

In the discussion of the results special refcreace is 
made to the work of Berliner and Berthelot, and it is 
pointed out that there is not sufficient evidence for the 
existence of such chemical compounds as PtjoHs and 
PtsoHa. Moreover, the authors are of opinion that the 
heats of combination of hydrogen and platinum as deter- 
mined by Berthelot and Favre are valueless, and that the 
heat which they measured is due, for the most part if not 
entirely, to the formation of water by the oxygen always 
contained in platinum black. It has yet to hefrovid 
that the absorption of hydrogen by pure platinum black 
is attended by the evolution of heat, and as regards the 
formation of supposed true chemical compounds, solid* 
solutions, or alloys, the authors prefer to wait Until suffi- 
cient data have been accumulated for an adequate inquiry 
before coming to any definite conclusion. 



ON THB 

FORGING OF FLAT CRUCIBLE STEEL INGOTS 

FOR TOOL MANUFACTURE. 

By SEROIUS KERN, M.E. 

In the Chemical News (Ixxi., p. 187) I gave a descrip- 
tion of my system of casting crucible steel ingots. I 
may add that the forging of ingots is going well, and the 
loss through piping is remarkably smaU. Capt. Trou- 
chanoff, manager of the forge of the New Admiralty, St. 
Petersburg, thus reports about my system :— 

** In many cases, during the manufadure of various 
tools at works, having for such work crucible steel ingots, 
it is much preferable to use flat ingots, cast by Mr. Kem*s 
system." 

St. Petertborg, June 2, 1895. 



NOTE ON "STANDARD" ACID SOLUTIONS. 
By H. DROOP RICHMOND. 

Dr. Perman and Mr. John describe (Chemical News, 
Ixxi., 296) a new method for standardising solutions. 
Seeing that it has been used for at least eight years, and 
has been exhaustivelv studied by Rimbach {atr,, xxvi., 
164), who even used the method of titration of borax with 
acid, methyl orange being employed as indicator, for the 
determination of the atomic weight of boron, it is not 
corredl to call it a new method. 

The process is certainly very convenient, and much 
more accurate than the results of Messrs. Perman and 
John would indicate — e,g,,& difference between duplicates 
of o'4 per cent is shown ; certain precautions are, how- 
ever, necessary, to which the authors have not drawn 
attention. From the very fad of the method being 
described as new, it is evidently not so well known as it 
should be, and consequently no excuse need be offered for 
describing the necessary precautions. 

It does not do to trust to the borax having the compo- 
sition Na2B407.ioOH3. The water of crystallisation 
should be estimated at the time of weighing out the 
borax ; half-an-hour's ignition in a muffle is usually neces- 
sary to drive off all the water. 

Commercial methyl-orange sometimes contains an 



Determination . of Water in Sulphate of Ammonia. 



i Chihical Nbws, 
t July 5. 1895. 



objediooable brown colouring-matter, which can, however, 
be removed by one or two crystallisations from alcohol. 

The solution of the borax should not be too strong ; 
about ao cc of water for each x ffrm. is convenient. If 
too large a proportion of neutral salts be present, the 
delicacy of the end readion is impaired ; this is probably 
the reason for the difference of 0*4 per cent in Messrs. 
Perman and John's results. 

An excellent method of preparing standard sulphuric 
acid is to weigh a quantity of acid of known density (best 
about 96 per cent HaS04), and dilute to a definite volume. 
The excellent work of Pickering {yourn. Chitn, Soc, 
Ivii., p. 64) has given us data for the calculation of the 
strength of sulphuric acid from the density with great 
exaditude. 

It must be remembered that, whether the sulphuric 
acid is weighed, or titrated with borax, or estimated with 
barium chloride, that the strength of our acid is expressed 
in terms of the aAnal sulphuric acid present ; when we 
come to use this acid in pradice, employing, as is very 
frequently the case, phenolphthalein as indicator, we 
have not only the acidity of the sulphuric acid, but also 
that of the dissolved carbonic acid, entering into the 
readiOD. We are usually very careful in keeping our 
alkali solutions free from carbonates (where they are of 
minor importance, as the alkali solution is always stan- 
dardised af;ainst acid solution), while we utterlv negleA 
all precautions for keeping our acid solutions free from 
carbonic acid. 

The atomic weight of boron seems to be from the de- 
terminations of Ramsay and Aston, and Rimbach, who 
both used borax, zo'95, and, adopting this and the atomic 
weights given by Clarke for sodium, oxygen, hydrogen, 
and sulphur and chlorine, z grm. of anhydrous borax is 
equal to 0*48575 grm. sulphuric acid and 0*36115 grm. 
hydrochloric acid. 



THE DETERMINATION OF WATER IN 

COMMERCIAL SAMPLES OF SULPHATE OF 

AMMONIA. 

By JOHN HUGHES, F.I.C. 

It is not generally usual to state the percentage o- 
water present in commercial samples of sulphate o- 
ammonia. 

Occasionally chemists are asked to do so, also to state 
the amount of acidity, and in such cases the figures are 
given ; but usually only the percentage of nitrogen equal 
to ammonia is reported. 

The writer thinks that it would be desirable and useful 
that the percentage of water lost at a 12^ F., and the 
acidity expressed as H2SO4, should always accompany 
the figures for nitrogen and ammonia on the certificate. 

Sulphate of ammonia, when ground up in a mortar, 
rapidly loses moisture in a hot dry atmosphere. 

Consequently, in order to make a correA report on the 
percentage of nitrogen contained in the sulphate of am- 
monia in its natural state as received, it becomes neces- 
sary to make two water determinations. One in the 
sample as turned out in its rough damp state before 
srinding, and one in the finely ground portion prepared 
for the purposes of analysis ; the analytical results beine 
afterwards calculated into the natural state as received 
and reported accordingly. 

The question of water really is a most important one, 
bearing in mind the commercial value of the material and 
the fad that every i per cent of water lost represents an 
increase of 0*25 per cent of ammonia. 

It is true that the introdudion of centrifugal machines 
has largely reduced the proportions of water and acidity 
in the sulphate of ammonia as sent out ; but there is still 
sufficient difference between the dampness, respeAively 
at the top and the bottom of the bags, to make the sam- 
pling a matter of great importance. 



The following twelve samples, representing one de- 
livery of yellow sulphate of ammonia, were furnished 
the writer by a large London manure firm, six bags 
being seleded, and samples drawn respedively, from the 
top and bottom of each. 

The proportions of water and acidity were then care- 
fully determined as above suggested, a weak solution of 
litmus being employed as indicator in titration for 
acidity. 

Top Samples. 

Water Free acid 

Water as Water h loit during calcaUtedas 

received, analysed. preparation. HaSO«. 

X.. •• 1*98 1*26 0*72 o'gy 

a*. •• x*8i 1*42 0*39 0*63 

3,. •• 1*59 1*20 o*39 0*65 

4.. •• 0*87 0-48 0*39 o*8i 

5., .. 1*12 0*50 0*62 0*79 

6., •• 1*32 0*72 060 1*03 



Average. • x-45 



X •• 
a •• 

3- 

5.- 

6.. 



0*93 0-52 o*8x 

Bottom Samples. 

Water Free acid 

lost daring calculated ai 

preparation. HaSO«. 

0*98 X*24 

071 0*8i 

0*77 0'8o 

x*oa X*22 

0*73 07X 

0-55 1-07 



Water at 


Water aa 


received. 


analysed. 


2*62 


164 


2*65 


1-94 


2*53 


176 


3-14 


3*13 


x*97 


1-34 


a-39 


1-84 



Average.. 2*55 x*76 079 0*97 

It will be noticed that the differences are considerable* 
the top samples being much drier than the bottom ones, 
in No. 4 the difference being as much as 2*27, representing 
0*56 ammonia; and the water lost during preparation 
amounting in some cases to over x per cent, representing 
0*25 ammonia. 

Of course this loss during preparation will vary with 
the degree of grinding, the time exposed, and the temper* 
ature and humidity of the atmosphere. 

The following figures in seven other samples, each 
representing a different delivery and analysed at a dif- 
terent time, will serve to indicate the variation that may 
be expedked :— 









Water 


Free acid 


Colour. 


Water ae 


Water ai 


lost during calculated at 




received. 


analyted. 


preparation. 


H,SO.. 


White.. 


• . 2*20 


X*8o 


0*40 


0*29 


Yellow.. 


.. 1*94 


X50 


044 


0*31 


Yellow.. 


.. 2*31 


2*o6 


0*25 


o'X5 


Grey .. 


.. 296 


274 


0*22 


0*38 


White.. 


.. 1*70 


x*xo 


o*6o 


0-X5 


White.. 


.. x*90 


1*40 


0*50 


0*23 


White .. 


.. x-89 


X*32 


0-57 


025 



Average •• 2'X3 x*70 0*42 0*95 

The amount of acidity is of importance, because if not 
excessive, say not more than 0*5 per cent, the sulphate 
of ammonia can safely be shipped m double bags instead 
of in the more expensive casks which were formerly used. 

If the certificate of the analyst contains information 
as to the percentage of water and acidity, in addition to 
the figures for nitrogen equal to ammonia, the identity of 
the sample with the bulk can be more readily established 
than when the figures for ammonia only are stated. 

In a paper published in the Chemical News (Ixii., 
p. 325) the writer drew attention to the importance of 
stating the percentage of water when reporting on the 
quality of wool waste, and pointed out that the omission 
to do so, and to state the percentage of nitrogen for the 
sample as received, had no doubt caused Uie serious 
differences between analysts, which up to that date was 
of frequent occurrence, but which since then have dis- 
appeared. 



( HffMICAIr NBVt, I 

July 5. >895- ' 



Nature and CompoUHdn of Commercial Russian Kerosene. 



He trusts that this communication niay be received by 
analysts in a similar favourable manner. 

79, Mark Lane, Loodon, B.C., 
June 20, 1895. 



ON THE NATURE AND COMPOSITION OF THE 
COMMERCIAL RUSSIAN KEROSENE. 
By ?. ALFRED WANKLYN and W. J. COOPBR. 

In December, 1893, and in January, 1894, in the Pkilo- 
iopkUal MagoMim and in the Chemical News, the an- 
nouncement was made that, by most persistent and 
methodical fradionation, a homologous series of hydro- 
carbons had been separated into its terms, and that its 
terms differed from one another, not by the common 
increment 14, but by the common increment 7. In fol- 
lowing papers we have disclosed that the hydrocarbons in 
question are the hydrocarbons existing in mixture in the 
commercial Russian kerosene, and have published further 
details. 

On the present occasion we publish a tabular nsumi of 
the work. The hydrocarbons of this series we have named 
keroses, and in the table the Roman numeral expresses 
the nomber of atoms of carbon (the atomic weight of car- 
bon being 6) in the molecule of the kerose. 

We have obtained an acetic compound of almost every 
individual kerose, one molecule of kerose being united 
with one little molecule of acetic acid. The preparation 
of such compounds was described in the Chemical News 
of May 24 (vol. Ixxi., p. 250). 

Percentage of 
V. D. Sp. gr. Boili Hydrocarbon in 

at at Acetic K. 

^ * ■ > xs'S^'C. •€. ^- « s 

Theory. Foaad. Theory. Found. 

Ay xiu. 3-144 3192 07350 

As »v. 3*386 3*43 07460 85 62*04 62*33 

Att XV. 363 3'^ 07510 96*5 6363 6275 

Ab xvL 3*87 391 07576 X06 65'i2 64*48 

B xvii. 4*ix 4*08 0*7606 ii6'5 66*48 65*9' 

Bb xviii. 4*35 4*36 0*7711 127 6774 6784 

Be xix. 4*59 4*59 0-7768 138 68-91 6906 

C XX. 4*84 4-84 0-7843 148 70-00 6970 

D xxi. 5-08 5*02 0-7975 158 71-01 70-94 

Vd xxii. 5-32 5*20 0*8057 168 71*96 72*00* 

D# xxiii. 5*56 5-5 X 0*8090 276 72*87 7299 

E xxiv. 5-80 5*77 0-8185 186 73-68 7401 

F XXV. 6*04 6*08 0-8240 197 74-47 74-64 

tf xxvi. 6*28 08255 205 75*2 X 75-28 

xxvii. 6*52 6-53 0*8270 2x4 75-90 77*02 
O^ xxviii. 6-77 682 08287 222 76*56 77 -3 X 
H xxix. 0*8338 230 77*x8 7753 
HA XXX, 08392 237 7777 77*53 

1 xxxi. 0*8430 246 78-34 78-34* 
K xxxii. 0-8470 253 7887 79-43 
L xxxiii. 0*8520 260 79-38 79*95 
II xxxiv. 0*8560 267 79-87 79-83 
N XXXV. 0-8590 274 8o*33 80-63' 
O xxxvi. 0*8603 280 8o*77 80*55 

•Mean. 

2 residue, dark coloured liquid, sp. gr. 0-880, amounting 
to about X3 per cent of the total kerosene. 

The circumstance that the specific gravity of the liquid 
keroee always rises as the molecule increases in weight 
will be noted. This rise is small, but invariable, and 
afiords an argument in favour of there being substantially 
only one hydrocarbon scries present in the Russian kero- 
sene of commerce. Apparently, however, the rise (though 
it always occurs) is not always equal in extent. 

The boiling-points of the keroses must be looked upon 
na to some extent provisional. We are in possession of 
the liquids and have not used them up in making the 
acetk compounds, and we purpose to re-determlne the 
boUtag-points. 



A REFORM IN CHEMICAL, PHYSICAL, AND 

TECHNICAL CALCULATIONS. 

By C. J. HANSSBN, C.B. 

(Continoed from p. 309). 

Thi Dynamic Equivalutt of Heat, 
If X cbm. hydrogen of atmospheric pressure and 273° N. 
absolute temperature is heated to 546*^ N. absolute (273^ 
increase of temperature), it expands to 2 cbm. of x atmo- 
sphere pressure ; it would, enclosed in a cylinder with 
movable piston of x sqr. m. area, by expanding, move the 
piston X m. against the pressure of the atmosphere ; and, 
consequently, as atmospheric pressure upon x sqr. ro. is 
SB 10330-442 kg., perform xo330*442 m.kp^r. of work. 
To heat x cbm. of hydrogen 273^ N., is required* 



At constant pressure 
At constant volume . 



273° X X7/56 cal. 
273°xx2/56 „ 



The difference 273" x 5/56 cal. — 

X365/56 « 24I calor. >■ 24*375 cal. has performed 
xo330'442 m.kgrs. of work ; consequently, — 

X cal.- '^330-44^ „ ^,3.3,3 ^.^g^ 
24*375 
Exaaiy the same result do we get by calculating with 
oxygen, nitrogen, or other simple gases, and likewise 
with CO and with air; but, by making the calculation 
with a compound gas which, in combining, has contraded 
its volume, the result is apfanntly different. 

For carbon dioxitU (of which x cbm. contains x| cbm. 
of simple gases, are required— 

At constant pressure •• •• 273^x51/1x2 cal. 
At constant volume •• •• 273*^x36/1x2 „ 

The difference 273°xx5/xx2 cat. — 

4095/xx2aB36|», calor., moves the piston x m., and perw 
forms X0330-442 m.kgrs. of work. This compound gas nat 
consequently absorbed exadly x| times as much neat at 
the simple gas, to perform the same amount of work, bat 
in this case,i of the 36,^ cal. — X2^0 cal., is absorbeid to 
counterad the chemical affinity which contraded x cbm. 
O and I cbm. C into x cbm. COa, and the remaining 
I X 36/^ = 241 calor. perform the same amount of dynamic 
work as in the first case. The same calculation made 
with many other gases, gives, with absolute accuracy, the 
same result: x calor. >■ 423*8x3 m.kgrs. 

Water evaporates in vacuum at 219}^ N. absolute 
(~53fl° N.), because, by very careful investigation of 
Regnault's experiments on evaporation of water, the 
author finds that in all cases, from the highest to the 
lowest temperature, — 

W X T 
y^^ - 219I 

Here T denotes the absolute temperature of the steam 
(°N.), W the weight of the steam (kgr. per cbm.), and P 
the absolute pressure of steam in atmospheres ; and for 
all weishts, pressures, and temperatures of stean ascer- 
tained by those experiments, the coefficient— 

2x9-375-2x91 -!Z55 

is the result. For every known pressure and weight of 
steam we consequently find the corresponding absolute 
temperature, T, by the equation— 

T - '-255P . jjo jj absolute. 
8W 

Aeriform substances increase in weight in inversi pro- 
portion to their absolute temperature; consequently, 
vapour of water (steam) of x atmosphere and 273° N. 
absolute, of which i cbm. weighs 45/56 kg., would weigh 
56/56 kg. (=: I kg.) if cooled, as proportion — 

56 : 45 - 273"* absolute : tt9t^ N. absotate. 



8 Reform in Chemical, Physical, and Technical Calculations. {^"^JVAST^ 



If at 219$° N. absolute x cbm. steam of x atmosphere 
weighs I kg., then i cbm. of o'oooooooi atmosphere must 
weigh O'OOOOOOOI kg. If we insert these values for P and 
W in the equation, we find the temperature — 

T ^1755 X O'OOOOOOOI atm. ^^ o n. abs.- -5310 N. 
8 X 0*00000001 kg. 

where water will commence to evaporate in absolute 
vacuum. By increasing the temperature, the pressure of 
steam increases in the following ratio : — 

Abtolate. 

2198 =- 53t 
2204? = - 5A\ 



Atmotpheret. 

0*00000001 . 
O'OOOOOOI • • 

0*000001 .. 

0*0000 X . . 
0*0001 

0*001 •• .. 



2205?+(\,VX 
2252 +(tf/X 
232I +(V7'X 

243 +(Wx 
+(Wx 

+ ('5VX 

+(V,Vx 
+(Wx 
+ (V/x 



259 

283 

3'9 
373 
454 



1.50) = 

I5») = 

iV) = 
I5») = 

iV) = 
1-5 •). 

i*5^)« 
i-5') = 



2255 

232i 

243 

259 

283 

>3i9 

'373 
•454 
= 5754 



= -471 
= - 40I 
«- 30 
= -14 
= + 10 
= +46 
« + ioo 
= + i8i 
= +302i 



0*01 .. .. 

0*1 .. .. 

X'O •• •• 

10*0 • • . . 

100*0 . . • . 

By calculating the temperatures due to 83 intermediate 
pressures, and of these construct a diagram, the author 
obtained a curve, which agrees well with Regnault*8 ex- 
periments ; in fadl, so well that the small deviations must 
be caused b^ ex1>erimtntal errors. 

The specific heat of liquid water, as usually taken, si ; 
the specific heat of ice (which is condensed HaO at con- 
stant volume), of vaporised water (steam), and of HaO ^as 
it ■:o*4. Melting i kgr. of ice absorbs 79^ calors, which 
become latent. Evaporating i kgr. of liquid water absorbs 
8x79^^634 calor., which become latent, minus 01 cal. 



'4. 



Heat rtquirtd to Mtlt Ice^ Vaporist and Decompose Water, 
1 kgr. solid HaO (ice) at absolute zero of temperature 
(0° abs.) contains no heat ;— 

Heated to 273° abs. (-f 0° N.) it con- 
tains 273x0*4 cal. .. 

Latent heat of Itquefadion of ice 



Total heat in x kgr. liquid water of 
273^ N. abs. (0° N.) 

Latent heat of evaporation per i kgr. 
liquid water of 273*^ N. absolute con- 
verted into vapour of 273 ** N. abs., 
634 cal. - (273° X 0*1 cal.) .. .. 

Total heat in i kgr. steam of 273° N. 
absolute (o® N.) 



xo9*20 calor. 
i88*45 „ 



60670 



79515 H 



These examples, which also hold good for lower and 
higher pressures, show that although if «o*4 calor. are re- 
quired to raise the temperature of x kgr. saturated steam 
x° N., only 0*3 calor. are to be supplied from outer sources 
of heat, while 0*1 calor., taken from the 634 calor. latent 
heat of evaporation, is converted into sensible heat or 
temperature. 

These 0*3 calor. are, in the process of evaporation, ap- 
plied thus : — 

\ B 10/90 calor. per x^ N. is used to overcome atmo- 
spheric resistance. 

i^ff^ 5/90 calor. is used to overcome chemical affinity 
of H and O. 

^ a 12/90 calor. is used to overcome physical cohesion 
of atoms. 



Heat required to evaporate i kgr. liquid water of 273^ N. 
absolute (0° N.) into steam of atmospheric pressure and 
373® N. absolute (xoo«* N.)— 

Latent heat of evaporation, 634 cal. 

- (373*' X 0*1 cal.) = 59670 calor. 

X kgr. steam heated 100° N. and 0*4 cal. <■ 40*00 „ 

To convert i kgr. water of o" N. into 
steam of 100^ N. requires •• .. 63670 „ 

To evaporate i kgr. water of 273° N. absolute into 
steam of xo atmospheres pressure and 454° N. absolute 
(181® N.), is required :— 

Latent heat of evaporation 634 cal. 

- 454°xo'i cal) «s 588-60 calor. 

X kgr. steam heated x8i° N. and 0*4 cal. = 72*40 ,« 



To convert i kgr. of water of 273° N. 
absolute (o** N.) into steam of 181^ 



N. requires . 



66x'oo 



27/90 calor. B 0*3 calor per 1° N. to be supplied 
from outer sources of heat. 
The 791 calor. + 634 calor « 713*25 calor. latent melt-, 
ing and evaporating heat required to evaporate x kgr. ice 
0° N. abs., decrease 0*3 calor. for every i* N. tempera- 
ture above absolute zero ; consequently, the absolute 
temperature, where water is converted into permanent 
HaO gas, is found by proportion :— 

o*3 cal. : 713 : 25 cal. — i'' N. : 2377*5° N. absol. 
Heating i kgr. HaO at constant pressure x° N. reqairet 
\l calor. ; consequently, raising the temperature from o* 
absolute to 2377*5** N. absolute requires — 

23775" N. X II cal. « X347J calor., 
which is equal to-~ 

(iH-84-8)X79jcal.= i7X79lcal.«. 13474 calor. 

Water Decomposed into Simple Hydrogen and Oxygen Gas. 

If we heat i kgr. of solid water (ice)« of o' N. absolute, 
to x| X 23771° N. absolute = 3566J* N. absolute, we 
have brought it to the temperature where the molecules 
of HaO decompose into simple H and O gas. To heat x 
kgr. of solid water of o^ N. absolute to this temperature 
are required— 

3566^'' N. X II cal. « 2020} calor. 
But in order adually to split the HaO molecules into 
simple hydrogen and oxygen gas of 3566I** N. absolute 
temperature, are required per x kgr. :— 

2 X 2020I calor. B 4041} calor., 
which is equal to^ 
3X(i+8+8)X79ical.-3Xi7X79l= 

=51 X 79i«404ii c*Jof* 

By this operation, the x kgr. of ice of o** N. abeolnte is 
dissolved into I kgr. of hydrogen and { kgr. of oxygen, 
which, at that temperature (3566^^ N. absolute), are 
*■ 634/39 cbm. hydrogen and 3x7/39 cbm. oxygen ■« total 
951/39 cbm. -r 24^y cbm. of simple gases of 3566I'' N. 
absolute and atmospheric pressure. 

As dissolving x kgr. of ice of o*" N. absolute temperature 
into its components requires 404x1 calor., it follows that 
the combustion of | kgr. hydrogen with $ kgr. oxygen 
(which form x kgr. of water), must likewise develop 404it 
calor. ; and, consequently, the combustion of i kgr. of H 
with 8 kgrs. of O, forming 9 kgrs. of water, will pro- 
duce : — 

9 kgrs. X 4041} calor. absolute « 36375 75 calor. total heat 
9 kgrs. of water of 273" N. abs. 

contain 9 x 188*45 ^^^* • • "■ 1696*05 „ 

Consequently— 
X kgr. hydrogen burnt with 
oxygen produces 34679*70 „ 

if the initial temperature of the gases has been 273° N. 
absolute, and the produdts of combustion are cooled down 
to that temperature ; and the temperature of combustion 
of H with O is 3566J' N. absolute, and 3566J' - 273" - 
+3293f N. 



CasmeAL Niwt, I 
July 5, 189s. f 



Relation between Valence and A tomic Volume. 



Pntsurg exirUd by FruBtng iVaUr.^Thig prestore the 
avtbor fiodt to be ■> 1904 atmosphercf • 

Water hermetically enclosed in a strong vessel 
renains liqatd at —34* C. (249^ C. absolute), as proved 
1^ M. Bouaingault's experiment ; andprobablv it remains 
liquid at all lower temperatures down to aigg^ N. abso- 
lute if expansion is absolutely prevented. 
(To bt contioQcd.) 
3, VaMmaracade, Copenhaffea, V. 
May 6, iSgs. 



SPBCTROSCOPIC STUDY OF THE CARBONS 

OF THE ELECTRIC FURNACE. 

By n. DESLANDRBS. 

H. M018SAN has recently annoanced (CompUt Rindus, 
cxix., p. 1245) ^^1*^ ^^® carbons of the arc in his eledric 
furnace are purified by the passage of currents of great 
intensity, and are thus freed from the foreign matters 
which they always contain in notable proportion. 

We know that it is very difiicult to purify charcoal b^ 
chemical means. This property of the eleAric furnace is 
therefore important, and in particular it interests spedro- 
acopiau who in their researches of qualitative analysis 
often employ eledrodes of carbon as pure as possible. I 
have thus been led to a special study of the carbons of 
the oledric furnace, to ascertain on the one hand their 
▼aloe in analysis, and on the other to determine the com- 
plete speArom of pure carbon. 

Mottaan having placed at my disposal two carbon poles, 
a positive and a negative (leneth of 0*20 metre and thick- 
Beaa of 0*05 metre), which had served in his experiments, 
I took from each pole small portions of charcoal at 
variable diatances from the arc (0*15, o'xo, 0*05, and 0*01). 
Now the specimens the most remote from the arc still 
showed the rays of the ordinary impurities of charcoal, 
if., the alkaUne and earthy-alkaline metals, with copper, 
iron, and ailicoa ; but on anproaching the arc, the rays of 
the imporities gradually diminishedf and finally disap- 
pearad, excepting only the rays of calcium, which, although 
OMch reduced, are still visible; this fad being due to the 
proxtmity of the sides of the furnace consisting of lime. 
These sides are themselves volatilised by very intense 
cnnenta. 

This purification of carbon seems to depend on a purely 
physical cause; the foreign matters, much more volatile 
than the carbon, are thrown off in the state of vapour. 
In fad, the purest parts of the two poles are the caps 
("mushrooms," aa the author calls them), which are 
lormed at the negative pole of transportation from the 
poaitiw pole to the opposite pole. With one of the caps 
the following spedrum of carbon has been obtained, con- 
tatniog fewer ravs than the aimilar spedrum published by 
Uveiog and Dewar, Hartley and Adeney, Eder and 
ValelKa^- 

laiesaitits. Wave-toogtba. 

8 426*70 

5 392«7l 

4 39i'97i> 

a 3«6-83r 

X 3>6'57i 

a •• • 29954 

X 29677 

8 28375 

8 28369 

4 ^7475 

3 864*12 

8 251-19 

8 25079 

10 24788 

8 • 22970 

■ Cam pus Riudui. 



RELATION BETWEEN VALENCE AND 

ATOMIC VOLUME. 

By HOLLAND CROMPTON. 

In these {Biruhtit xxvii., p. 2178 —compare also Ziii, /• 
Anorg, ChemUt viii., p. 127) J. Traube shows the exist- 
ence of a relation between valence and atomic volume, 
and that the '* change of valence of an elementary atom 
is mostly attended with a change of the atomic volume," 
the atomic volume here in question being the atomic 
solution volume. 

In a memoir which I have recently submitted to the 
Chemical Society of London, I showed that there exists 
an intimate relation between the molecular (or atomic) 
latent heat of fusion, p, and the valences of the atoms 
present in the molecule, so that it is pORsible, by means 
of certain simple rules laid down in the memoir, to deduce 
from the valences a number £V, such that p To ■" CSV, 
where To signifies the melting-point in absolute degrees 
of temperature, and C is a constant which haa the same 
value for all substances. The connedion of the latest 
heat of fusion with the valence leads to the following 
confirmation of Traube*s results :^ 

In the year 1870 Goldberg ICompt, Rend., Ixx., p. 1349) 
established the following relation between the vapour- 

f pressure p* of a solution of the melting-point T in abso- 
ute temperature, and the vapour-pressure P of tho 
solvent of the melting-point To: 

p' R To T 

where R is the constant of the Boyle-Gay Lussac equa- 
tion. It may now be shown, thermo-dsmamically (Nemst, 
"Theoret. Chemie, p. 125), that if P is the osmotic 
pressure of a solution in which a change of volume if « is 
efieded by the removal of dx grms. of the solvent, the 
equation holds good : — 

P milRTlnt. 

dv p' 

If this formula Is combined with that of Goldberg, we 
have— 

P 

dx 



^^^ ^- - CSV. 



To-T dx To 

Here dv/dx is the volume occupied by i mol. of the 
solvent in the given solution; therefore the molecular 
volume of the solvent, or that part of the solution which 
separates out at the point of fusion, is the dissolved salt 
in solutions near on saturation for which Traube*s rela- 
tion is applicable. Consequently the molecular volume of 
a salt is a fundion of the valences of the atoms forming 
the molecule. — BtrichU, xxviii., No. 2, p. 148. 



EXAMINATION OF BLOOD-PIGMENT 

AS TO ITS POWER OF ABSORBING THE 

VIOLET AND ULTRA-VIOLET RAVa* 

By H. GRABBB. 

As the source of light, the author used in part sunlight 
and in part the light of the eledrical spark, the spedrum 
of which extends to six or seven times the length of the 
visible spedrum beyond H. The indudion current of a 
Ruhmkorff apparatus was excited by four Bunsen ele- 
ments, and served to charge a battery of nine Leyden 
jars. In most of the investigations an iron and a copper 
pole were used. The division of the spedrum thus ob- 
tained was effeded by comparison with the photograph of 
the spedrum of a spark obtained under exadly the same 

• Aa Inavcoral Diiscnattoo at Dot pat, 1891. 



10 



Examination of Blood Pigment. 



f CntMICALNlWI, 

1 July 5. 1895. 



conditions, and which had passed between the poles of an 
alloy of lead, tin, and cadmium ; the wave-lengths of the 
lines of the latter spedirum were obtained from a paper of 
Hartley's {Phil. Trans., 1885). As the achromatic colli- 
mator lens generally employed for photographs extending 
beyond H (consisting of a plano-convex lens of calcareous 
spar and a bi-convex quartz lens) was not at hand, the 
author used a chromatic quartz lens, which certainly 
showed only one part of the spedrum distin^ly, whilst 
the other parts could be successively adjusted sharply by 
a corresponding rotatory movement of the quartz prism. 
The displaceable slit of the spedroscope constru^ed by 
the author was placed, accurately centred, at double the 
focal distance of the lens. Immediately behind the lens 
was the prism, so adjusted on a movable axle that its 
requisite rotation could be regulated by means of a scale 
and index. As troughs there were used vessels of rock 
crystal, with plane parallel sides. 

For the proofs there were used the Lumi^re*s ordinary 
silver-bromide plates. The time of exposure varied ac- 
cording to the state of the sunlight, from 30 to 120 
seconds, and for the light of the spark between 200 and 
xoo elediric discharges. The proofs were developed with 
iron oxalate, and fixed with a 15 per cent solution of 
hyposulphite. 

Soret (Comptes Rtnins, xcvii., 1269) had observed the 
absorption of blood in the violet, and mentions also two 
absorption bands, '* one of which, at Cdxa, is probably 
due to haemoglobine, whilst the other, at Cdi7, is evidently 
produced by the serum.** D*Ar8onvaI has also recognised 
the absorption band of oxyhsemoglobine in the violet. 
The author, whilst making use of these former researches, 
has studied, by the aid of photographs, the absorptions of 
oxyhaemoglobine, hsmoglobine, methaemoglobine, cyan- 
methsemo^lobine, sulphomethiemoglobine, carbonic oxide 
haemoglobme, haematine, hsemochromogen, and haemine, 
in the violet and ultra- violet. He observed the following 
absorptions :~ 

a. Oxyhamoglobini,—A defibrinised solution of blood 
(20 per cent in a stratum of i m.m. in depth) absorbed 
the rays of the wave-lengths A 465 to X 358 ; a solution of 
10 per cent absorbed from A 450 to X 381. If blood was 
diluted to 5 per cent the band extended from X 440 to 
X 396. A I per cent solution of blood showed in the 
yellow and the green merely a faint darkening, whilst 
there appeared a distind band between X 427 and X 405. 
On further dilution the breadth of the absorption band 
decreases little ; it declines in intensity, and entirely dis- 
appears at a dilution of x : 600. 

b. Hamoglobint.-^V 01 reducing oxyhaemoglobine there 
was used ammonium sulphide, or a solution of x part 
ferrous sulphate and x part tartaric acid in xo parts of 
water, to which, shortly before use, 6 parts of '* officinal 
liquid ammonia*' are added. (Why does not the author 
express the strength of his ammonia in some standard 
universally understood ?) Both redudion liquids must be 
as nearly colourless as possible before use, as they will 
otherwise darken the violet. A solution of hsemoglobine 
diluted to xo per cent is impervious to the rays from X 450 
to X 398, and one at 5 per cent from x 447 to x 408. The 
absorption in the violet here undergoes, in comparison 
with oxyhsemoglobine, a displacement towards the less 
refrangible part of the spedrum. The middle of the 
absorption band coincides with Frauenhofer's G line, 
and with a i per cent solution the absorption band- 
sharply defined on both sides— is visible in the violet be- 
tween X 437 and X 417. Hsemoglobine has therefore, in 
the visible part of the spedrum, not one absorption band, 
but two bands. In the ultra-violet haemoglobine is dis- 
tinsuished from oxyhaemoglobine merely by a stronger 
darkening of the most refrangible rays. A 6 per cent so- 
lution is transmissive to about X 240. 

c. Mtihamoglobin was generally obtained by adding 
potassium ferricyanide to a solution of blood. The 10 per 
cent solution, in which the four absorption bands may 
still be distindlly recognised in the visible spe^um, ab- 



sorbs in the violet from X 440 to X 358. The band seems 
washed out towards the ultra-violet on diluting the solu- 
tion. If mixed with equal parts of distilled water, this 
solution absorbs from X 430 to X 382 ; if diluted to i per 
cent it allows all the light to pass through without hin- 
drance as far as the violet rays from X 420 to X 400. In 
the ultra-violet, except a darkening of the most refran- 
gible rays, there occurs no independent absorption. 

By the addition of a small quantity of ammonia or 
potassium hydroxide the above* described image charac- 
teristic for methaemoglobine (in the so-called acid solution) 
disappears, and there appears a speArum similar to that 
of oxyhaemoglobine, though the first absorption band is 
split into two. 

Besides the two or three bands the author observed, on 
sufficient concentration, also an absorption band in the 
green between X 555 and X 525, which he has not found 
already described. The band in the violet in a xo per 
cent solution extends beyond H to X 3751 and the side 
situate towards the red extends to X 445. If the solution 
is diluted to 5 per cent only traces of absorption are to 
be found in the yellow and the green, whilst the space 
between the Frauenhofer lines G and H is darkened. In 
a X per cent solution the band recedes on one side to 
X 415 and on the other to X 405. In the invisible spedrum 
the only difference between methaemoglobine in an acid 
solution and in an alkaline solution is that by the latter 
the extreme ultra-violet is more strongly darkened. 

if. Cyanmethamoglobinit readily obtained by the addi- 
tion of hydrocyanic acid to solutions of methaemoglobine, 
behaves like haemoglobine ; but in a i per cent solution, 
in a stratum of x m.m. in depth, absorbs the light rays 
from X 580 to X 523. The darkening of the violet extends 
beyond H, gradually fading from X 450 to X 381. On the 
addition of hydrocyanic acid the methaemoglobine band 
in the violet is therefore displaced towards the red. This 
phenomenon is observed more distinAly in a x per cent 
solution where the chief absorption is situate between 
X 430 and X 410. The photographic image of the ultra- 
violet show6 that the most refrangible rays are absorbed 
by cyanmethaemoglobine, which increases with the in- 
creasing concentration of the solution. 

i. Sulphomethirmoglobim, obtained by the adion of hy- 
drogen sulphide upon oxyhaemoglobine or haemoglobine, 
besides the absorption band in the red, displays a band in 
the violet, and a darkening in the ultra-violet similar to 
that of methaemoglobine. A 10 pir cent solution absorbs 
from X 452 to X 400 : in a 5 per cent solution the limits 
of the band are seen at X 440 and X 408. A x per cent 
solution of blood treated with hydrogen sulphide absorbs 
from X 427 to X 4x5. 

/. Carbon monoxide hamoglobim likewise displajrs an 
absorption in the violet, even at so great a dilution that 
the bands in the yellow and the green are no longer visible. 
A 10 per cent solution of carbon monoxide blood shows 
on the photographic plate an absorption from X 440 to 
X 388. A 5 per cent solution absorbs from \ 430 to X 407. 
If the solution contains x per cent of carbon monoxide 
blood the two charaderistic bands in the yellow-green 
disappear, but the band in the violet is seen between 
X 425 and X 41X. 

g, Hamatint was obtained by boiling an ammoniacal 
solution of blood, or one mixed with acetic acid. The 
absorptive power of acid haematine is exceedingly feeble 
for the violet rays on this side of H. Beyond H, both 
when the sun or the eledric spark is used as a source of 
light, a very slight darkening, beginning at H and ex- 
tending to about Cdx2. 

The alkaline solution of haematine, even if much 
diluted, shows a band, certainly much washed out ; its 
limits for a 10 per cent solution may be fixed between 
X 432 and X 348 ; a 5 per cent solution displays merely a 
darkening of the rays between X 425 and X 358. Besides 
an absorption of the extreme ultra-violet rays, there 
occurs in both cases a faint darkening at Cdu and Cdi7. 

h, Hamochromogin is formed on treating soliitions o 



CBBMICALNlWf, I 

nly 5. X895. f 



Chemical Notices from Foreign Sources. 



II 



hsmatioe with alkaline reduAive agents. In the forensic 
demonstration of blood this substance plays a great part, 
on account of its uncommonly visible absorption bands ; 
since solutions of blood*spots many years old, whose 
hasmatine bands would be visible only in the red, and 
visible only in very concentrated solutions if converted 
into hjemochromogen, show distin^ absorptions in the 
green even when strongly diluted. Haemochromogen is 
the more sharply charaAerised by its absorption band in 
the violet, which becomes visible on great dilution, and is 
therefore still more valuable for a judicial investigation. 
A solution at li per cent which transmits yellow and 
green light without hindrance, and consequently does not 
allow the recognition of the well-known absorption 
spe^mm, still absorbs strongly the rays from A 430 to 
X 418. A X per cent solution causes the disappearance of 
the rays between O and H in the spedrum ; a zo per cent 
solution absorbs the rays from A 443 to A 400. 

The most refrangible ultra-violet rays are strongly ab- 
sorbed by haemochromogen ; a 4 per cent solution is im- 
pervious to rays more refrangible than Cdiy. 

f. Hamn^ or haematine hydrochlorate, dissolved in 
methyl alcohol, shows in the violet an absorption band, 
the middle of which coincides with H. The hsemin solu- 
tion is perfedlly transmissive for ultra-violet light. 

According to all the above the absorption band of the 
blood-pigment, as well as of its derivatives, is more per- 
roanent than the already more generally known and 
repeatedly described absorption bands in the visible part 
of the spedrum. 

Hence it appears the more important that in hsemo« 
globtne, carbon-monoxide haemoglobine, and haemochro- 
mogen, the absorption band in the violet enters into the 
visible part of the spe^rum, and can be observed by the 
employment of diffused sunlight as a band defined on 
both sides. According to the observations of d'Arsonval 
the violet of the spe^rum can be strongly extended to- 
wards the ultra-violet if the sunU dired rays or the light 
of an arc, concentrated by a lens of 10 cm. in diameter 
with a very short focus, are allowed to fall into the slit of 
a speAroscope, and the dazzling rays from red to blue 
are eliminated by means of a disc of deep blue glass. 
In this manner of observation prisms and lenses of glass 
may be used, which is of the greatest importance for 
pradical detedlion. 

In connexion with this subjed I may mention two re- 
marks of A. Wetzel (Chemiktr Zeit.^ xiv.. Rep, 87) on 
the recognition of blood containing carbon monoxide. 
He shakes gently 10 c.c. of the substance in question 
with 15 c.c. of a 20 per cent solution of potassium ferro- 
cyanide and 2 c.c. of acetic acid of medium strength 
(t vol. glacial acid and 2 vols, water), whereon the blood 
coagulates to a mass which gradually solidifies. Normal 
blood yields a black-brown clot, blood containing carbon 
monoxide a light red. Or we dilute i part blood with 
4 parts water, add thrice the volume of solution of tannin, 
and shake round. The difference of colour between nor- 
mal blood and that containing carbon monoxide increases 
on standing. After twenty*four hours the normal blood is 
grey, and that containing carbon monoxide crimson red. 
The difference is still to be distinguished after ten months. 
— Zeiiichrift fur Anal, Chem,t xxxiii., p. 771. 



CORRESPONDENCE. 

USB OF MINERAL OIL FOR EXCLUDING 
AIR IN PAVY TITRATIONS. 

To th< Editor of the Chemical News, 
Sir, — I have delayed replying to Professor Brauner*s 
letter published in the Chemical News (vol. Ixxi., p. 292) 
until I had ascertained whether there was any foundation 
for his suggestion that one of the secretaries of the Che- 



mical Society, ** who alont are responsible for the 
abstrads in the Procudings,** had taken the astounding 
course of substituting the name '* Allen " for that of 
" Soxhlet *' in the abstrad in (question. 

I am now in a position to inform your readers, upon 
official authority, that the Secretaries of the Chemical 
Societv are not responsible for the above change of name, 
alleged by Professor Brauner to have been made. 

Professor Brauner says that '* instead of charging him 
with dishonest adion, I should have sent him a copy of 
my paper, and given him private information." Unmrtu- 
nately, at the time when the abstraA appeared I was not 
aware of the existence of Professor Brauner, whom I 
know simply as the reader of certain papers before the 
Chemical Society on March 2xst. I did all I could to 
communicate with Professor Brauner. I wrote to the 
Secretaries of the Chemical Society, informing them that 
the device had been previously described by me in three 
different journals, and I added : ** The prior publication 
of the suggestion has evidently been overlooked by 
Professor Brauner, to whom I shall be obliged if you will 
forward this letter or communicate its substance.*' I am 
informed by the Secretaries that this request was promptly 
complied with, and have learned later that their letter 
did not receive any acknowledgment from Professor 
Brauner, who now states that he did not receive it. 

As to the value of the use of mineral oil to exclude air 
in performing Pavy titrations, it is curious that the device 
is the only point in the paper communicated by Professor 
Brauner which the Secretaries of the Chemical Society 
appear to have considered worth including in the abstra^ 
which they prepared.— I am, &c., 

Alfred H. Allen. 

Sheffield, July x, 1895. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

NoTs.— All degrees of temperature are Centigrade unless otherwise 
expressed. 

Comptes Rendus Hebdomadaires des Seances, de V Academic 
dcs Sciences, Vol. cxx., No. 24, June 17, 1895. 

Professor Newcomb was eleAed as a Forei jn Associate 
of the Academy, vice the late Prof, von Helmholtz. 
Herr Bachlund was eledled a correspondent of the SeAion 
of Astronomy, vic$ the late R. Wolff; and Dr. Kowalewski 
correspondent of the Sedion of Anatomy and Zoology, 
vict the late M. Cotteau. 

Law of Absorption of the Bands of the Spedtrum 
of Oxygen.— J. Jansen.— The law is that the absorbent 
power of oxygen gas, relatively to these bands, is propor- 
tional to the thickness of the gaseous mass multiplied by 
the square of its density. 

Combination of Free Nitrogen with the Blementr 
of Carbon Oisulpbide.^ M. Berthelot.~The author, 
whilst pursuing his researches on argon, has recognised 
the diredl combination of free nitrogen with the elements 
of carbon disiilphide. This combination takes place by 
the influence of eledricity employed in the form of sparks 
or of the effluve. When operating on 15 c.c. of nitrogen 
at normal pressure, the volume having been increased to 
25 c.c. bv the addition of a small quantity of liquid car- 
bon disuiphide, carbon and sulphur are precipitated mixed 
with condensed carbon subsulphides ; at the same time, 
nitrogen is fixed on the products. 

New Combination of Argon : Synthesis and 
Analysis. — M. Berthelot. — (See p. i). 

Preparation and Properties of Pure Melted Molyb- 
denum.— Henri Moissan.- (See p. 2). 

A<5\ion of Phen>l Isocyanate upon the Campholic. 
Carboxyl-campholic, and Phthalic Acids.— A. Haller. 



12 



Immunity against the Poison of the Cobra. 



i CRBMICAI. NlWS, 

1 July 5. 1895. 



— The compounds obtained arc the hydroxycampho- 
carbonic, iso-, and terc-phthalic acids. 

Discovery of a Third Permanent Radiation of the 
Solar Atmoaphere in the Qas of ClSveite. — H. 
Deslandres.— The permanent radiation of the solar atmo- 
aphere, X 706*55, 18 emitted by the gat of cl^veile, and U 
even seems to announce a new element common to the 
solar and terrestrial atmospheres. There is now only a 
sinele permanent radiation of the solar atmosphere which 
has not been recognised on the earth ; that is the green 
ray \ 531-16, called the ray of the corona. It is distm- 
guished as being peculiar to the most elevated regions of 
the atmosphere, which allows us to suppose that it be- 
longs to a gas lighter than hydrogen. 

Molecular Transformations of Chromic Hydrate. 
—A Recoura.— The author has previously shown {Ann. 
di Chim. ei de Physique, Scries 7, vol. iv.) the existence 
of two varieties of chromium hydroxide, differing from 
each other by their capacity of saturationfor acids, i. The 
normal hydroxide is the precipitate produced by alkalis in 
the solution of a normal salt of chromium. It can fix 6 
mols. of hydrochloric acid, evolving 41 '4 pal. " « X og, 
and regenerating normal chromium chlorute. The chro- 
mium hydroxide of the green solution is formed by de- 
composing by an alkali a solution of a salt of chromium 
previously rendered green by ebullition. It fixes only 4 
mols. of hydrochloric acid. Chromium hydroxide, a 
hexatomic base, is transformed into a monatomic base, 
like the alkaline bases, after remaining for three hours in 
soda. If left for a longer time, it becomes a mixture of 
monatomic hydrate and of a hydrate ol no atomicity. 

Certain Basic Haloid Compounds of the Alkaline- 
Earthy Metals.— M.TaMilly.— The author has prepared 
and examined the strontium oxybromide and oxyiodide, 
and the corresponding barium salts. 

A<5tion of Heat upon the Double Alkaline Nitriles 
of the Metals of the Platinum Group : Compounds 
of Iridium.— A. Joly and E. Leidy.— The study of the 
double nitriles of iridium and the alkaline metals presents 
more difficulties than that of the corresponding com- 
pounds of ruthenium and rhodium. The double insoluble 
iridium and potassium salt is not remote from 
(IrO)60<(OK)2, which would be the potassium salt of a 
hexairidious acid. On operating at incipient ledness in 
a muffle, the authors obtain a salt approximatmg to the 
formula lalrOa.KaO, the potassium salt of a dodec^iridious 
acid. 

On the Acid Ammonium Sodium Tungstates.— 
L A. Hallopeau.— The author has obtained two salts, 
i6WO«.^Na203(NH4)aO-»-22HaO. which loses 15 mols. 
ifSr at i^'; and iiWOs^NaaO.CNHJaO+asHaO. 
losing 19 mols. of water. 

Rotatory Powers of some Amylic Derivatives in 
the State of Liquid and of Vapour.— Ph. A. Guyeand 
A. P. do Amaral.— The results of the authors are given m 
the form of tables. 

BulUtin dela SocUte a'Encouragerrunt pour V Industrie 
Nationale, Series 4, Vol. x.. No. xii. 

New Process for the Purification of a large number 
of Organic Substances. Alimentary and Otherwise ; 
in particular, Sugars, Alcohols, Potable Waters, &c. 
— E. Maumene.— The author^s invention is the employ- 
ment of a permanganate (potassium or calcium). The 
novelty of the process, as far as water is concerned, needs 
no discussion, since it is admitted in a foot-note that it is 
used by several London water companies. 

Alloys of Iron and Chrome.— R. A. Hadbeld.— 
{Journal of the Iron and Steel Institute). Abstraded by 
R. Masse. 

Composition and Constitution of certain Alloys. 
— C. R. A. Wright.— From the Journal of the Society of 
Chmical Industry. 



Progress of the Blast Furnace.- Paul Bayard.— It is 
here remarked that it is in Germany where the Thomas 
and Gilchrist process has made the most rapid and the 
most considerable progress. In 1883 it was onder 500,000 
tons, and has now reached 2| miilioDS. 



MISCELLANEOUS. 

Immunity against the Poison of the Cobra.— Ac- 
cording to a paper read before the Royal Society of 
Edinburgh by Prof. T. R. Fraser, animals— man included 
—can be made non-susceptible to the venom of the cobra 
by the injedion of minimal doses, gradually increased. 
He determined firstly the minimum dose fatal to rabbiu, 
and then gradually increased the quantity until he reached 
an amount fifty times greater than the original fatal limit. 
A rabbit which he exhibited had thus received, in one 
hundred and fifty days, cobra poison enough to kill two 
horses 1 The effe^ on the general health of the subjed 
was favourable; it had increased in weight from 2000 
grms. to 3000 ; whilst its strength, and especially its virile 
power, was signally aufl[mented. A successful antidote 
for the poison of the cobra is found to be a mixture of 
niv c.c. of the serum of a rabbit immunised up to thirty 
times the minimum fatal dose. We fear, however, that 
the shrieks of the zodphilists will render this process use- 
less in the British Empire. 



NOTES AND QUERIES. 

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of transmitting merely private information, or such trade notices 
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EleAric Furnace.— I shall be pleased if any correspondent can 

supply me with information relating to eleAric furnaces for laboratory 

purposes. --Chbm ist . 



ACETONE — ^Answering all requirements. 

J^CXX^ J^CETIO-Purest and sweet. 

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LIQUID CHLORINE 

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FORMALIN (40^ CHaO)— Antiseptic and Preservative. 

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FOR SALE. — The Chemical Gazette. 
Complete Set (ant)ound and uncut), 17 volumes ; from Novem- 
ber. 1842. to December. iSw.-AddreM. " PublUber," CaaiciCAL 
Naws Office, Boy Court, LrOdgate Hill, Loadoa, B.C. 



July la, 18,5. 



I 



New Studies on the Fluorescence of Argon. 



13 



THE CHEMICAL NEWS. 

Vol. LXXII.. No. 1859. 



NEW STUDIES ON THE FLUORESCENCE OF 

ARGON, AND ON ITS COMBINATION WITH 

THE ELEMENTS OF BENZENE. 

By M. BERTHELOT. 

I RAVB thoaght it useful to study in a more thorough 
mmnner the conditions of the combination of argon with 
beaxene under the influence of the eledrie efflave, and 
those of the special fluorescence which accompanies it. 

M. Dcslandres, whose special competence in questions 
of photography is known to the Academy, has kindly lent 
me his assistance for these new determinations effedled 
by means of stronger dispersions and defined by accurate 
photographs. It is my duty to express to him my thanks 
for this prolonged and difficult study. 

We must remember that the combination of argon with 
the elements of beniene under the influence of the efHuve 
U efleAed slowly ; according to the present research it is 
effeAed with the cooperation of mercury, which intervenes 
in the state of a volatile compound. The use of dis* 
charges of great frequency does not appear to modify the 
general chara^ers of the rea^ion. 

At the outset we perceive nothing in diffused light ; it 
is only in the dark room that we perceive a feeble violet 
light, similar in its intensity to that which the effluve 
generally develops in gaseous systems. After the lapse 
of an hour in the dark room we see a green light ap- 
pearing, which occupies the middle of the interval 
Mlween the spirals of the band of platinum coiled 
around the efBuve tube ; the luminous spe^rum presents 
two yellow rays, 579 and 577 (in wave-lengths), a green 
ray, 546, and a green band, \ 516*5, These various rays 
will be defined presently. 

The photographic spedrum now taken, with an hour*s 
exposure, shows the principal bands of nitrogen, as well 
as a blue ray, 436, a violet ray, 405, and an ultra-violet 
ray, 354; these latter are fainter than the bands of 
nitrogen. 

During the successive hours the green light augments 
without ceasing, the yellow rays and the ray 546 increase, 
and the band 516*5 diminishes. After eight hours the 
bands of nitrogen have almost disappeared in the photo- 
graphs, doubless because the corresponding nitrogen has 
been absorbed by the bensene. 

Several further hours of effluve bring the fluorescence 
to a brilliant emerald light, visible in full daylight : the 
intensity of this phenomenon is not comparable with the 
fluorescence developed by the effluve in any known gas. 
The yellow and green rays may be seen and defined by 
spedroscope in full daylight. 

The photographs have shown the rays 579, 577, and 
546; 436, 405, 354, 313. and 31a (ultra-violet). We per. 
ceive, further, two violet rays, 420 and 416, scarcely 
visible, and the rays 385 and 358. 

The speArum observed at the end of fifteen hours 
remained constant during thirty consecutive hours. 

Although we have had recourse to photography to 
register these phenomena, we must not confound such 
emAs observable in full daylight, and at a normal 
pressure, with the lights developed by the effluve on 
highly rarefied gases, such as are commonly observed 
with the speAroscope. 

This is the signification of these rays : — 

The ray 579 is precisely one of the rays visible in full 
daylight, and at normal pressure which I have mentioned 
iCamPtiS RtnduSf cxx., p. 800), indicating its probable 
fission. We must approximate to it the rays 580*1 and 



577*1, mentioned in the speArum of rarefied argon by Mr. 
Crookes (Jan. 24, 1895). The ray 546 has also oeen indi* 
cated (547) in my former paper, and corresponds to a 
strong ray, 545*6, exhibited by Mr. Crookes to the speArum 
of rarefied argon. M. Deslandres has recognised these 
same rays in the spedrum of a specimen of rarefied argon 
which he had prepared by means of lithium. I have veri- 
fied, by juxtaposition, the coincidence of the latter ray of 
rarefied argon with that of my effluve* tube. I have also 
pointed out the ray 436, found in the photograph, and 
very near to the 4345 of the rarefied argon by Crookes. 
The rays 420 and 416 coincide with the very strong rays 
420*1 — 4198 and 415*96 of the rarefied argon of Crookes. 
The ray 405 may be identified with the ray 404*4 of 
Crookes (argon) ; I have verified the coincidence. The 
ray 385 coincides with a strong ray 385*15 of Crookes 
(argon) ; the ray 354 with a group of 3547— 353*4 of 
strong rays of rarefied argon (Crookes), and the ray 358 
with a group of strong rays 3587—357*5, observed by 
Crookes (in argon); A 516*5 is a band of rarefied hydro- 
carbides; 313 and 312 are rays of the rarefied vapour of 
mercury. 

None of these rays, as I have already remarked, coin- 
cides either with the ray of helium (587*5) or the principal 
ray of the aurora borealis (557), though this latter falls 
very near to a strong ray of argon (555.7). If the present 
fluorescence is not tne same as that of the aurora, yet its 
development and the approximation of the rays above 
mentioned establish a probable relation between this 
meteor and the occurrence of ar^on in the atmosphere. 

There appears here a very important drcumstance. 
Already, on examining the table of the rays of rarefied 
argon given by Mr. Crookes, we recognise that certain of 
these rays coincide with certain of the rays of the rarefied 
vapour of mercury. The same coincidence is obserred 
also in the finest rays visible in full daylight, at the nor- 
mal pressure, .in the fluorescence developed during the 
readion of benzene upon argon. Such are, according to 
M. Deslandres, the yellow rays 579 and 577 ; such is the 
charaderistic green ray 5461 such are the blue ray 436,' 
the violet ray 405, and the ultra-violet ray 354. On the 
contrary, the rays 420, 4x6, 385, and 358, belong only to 
argon, and the rays 313 and 3x2 to mercury. 

M. Deslandres attributes the presence of the common 
rays to the presence of the vapour of mercury either in 
the rarefied argon or in the fluorescent light obtained with 
benzine at a normal pressure. 

Nevertheless, as no known gas furnishes either this 
fluorescence or these rays, under the normal pressure, 
when operating over mercury, it is not possible to explain 
its formation) by the mere presence of this vapour. 
Otherwise we could not comprehend why they do not 
equally originate with pure argon in presence of mercury 
at the normal pressure, and why they are not produced at 
the first moments of the effluve neither with argon satu- 
rated with benzene or carbon disulphide over mercury, 
nor with nitrogen under the same conditions in which it 
combines with benzene and carbon disulphide. On the 
contrary, with argon saturated with benzene they are 
developed only after the lapse of several hours, and con- 
sequently of the progressive transformation of the benzene 
into one of a series ofcompounds more and more condensed. 
It is one of these compounds which, at the moment of its 
formation, commences to unite simultaneously with argon 
and mercury, associated possibly in virtue of their common 
charaaer of monatomic molecules. The fluorescence 
begios whilst there still exists in the^tubes a considerable 
proportion of liquid benzene ; it is then accompanied by 
a decrease of the gaseous volume. 

This fluorescence subsists for a very long time, even 
after the benzene is no longer perceptible ; finally the 
fluorescence ceases to manifest itself in full daylight, in 
consequence of the very prolonged aAion of the effluve» 
which at length causes the green tint to disappear, and 
brings back this gaseous system to a luminosity like that 
of ordinary gases. This happens doubtless in consequence 



14 



On Argon. 



of the total destrudlion of the last traces of benzene and 
of the intermediate condensation products, which would 
maintain the equilibrium of dissociation of the system. 

When once the green fluorescence is well established, 
the compounds which develope it are stable, per st ; for it 
suffices, even after twelve hours of rest, without having 
disarranged the apparatus to cause the efHuve to adl anew, 
to re-establish the fluorescence, in all its splendour, in 
less than a minute. It is. however, extinguished imme- 
diately as soon as the ele<^ric a^ion is suspended. 

But if we separate the gas from the condensed matter, 
the phenomenon can be no longer reproduced immediately 
either upon the one or the other. The gas alone, if sub- 
mitted to the aAion of the effluve, acquires almost imme- 
diately a peculiar violet fluorescence, visible in the dark, 
and which precedes the development of the beautiful 
green fluorescence. Still this is not then reproduced, 
which seems to indicate that the condensed matter may 
contain one of the produAs necessary for the equilibrium. 
If, on the other hand, we re-introduce fresh argon into the 
tube containing the condensed matter (free from visible 
benzene) the green fluorescence is not reproduced in its 
totality, but at the end of some time we see appear near 
the surface of the mercury, there where the rain of fire is 
most intense, a localised green tint which presents specific 
rays, though in a manner not very distinct. Their appear- 
ance is due, no doubt, to the existence (or the regeneration) 
of a trace of benzene, more or less modified. In fadt, if 
we then introduce a few drops of liquid benzene into the 
tube containing the condensed matter and the fresh argon 
over the mercury, the adtion of the effluve for half an hour 
is sufficient to cause the green tint to re-appear in full 
splendour. But if there is an excess of benzene the phe- 
nomenon requires several hours for its re appearance. 

These various observations, in conjundion with the 
limited charader of the absorption of argon, show the 
existence of a complex equilibrium in which there intervene 
at once argon, mercury, and the elements of benzene, or 
rather a condensed compound derived from them.— 
Comftes Rendu$t cxx., p. 1386. 



t Chemical Nbws, 
\ Joiy la, 1895. 

admissible. Hence the assumption of an atomic weight 
A a 40 is scarcely probable. 

To the second supposition, A2. there corresponds an 
atomic weight a 20, and argon must be introduced into 
the eighth group of the second series, i. /., immediately 
after fluorine and before sodium, which is also not too pro- 
bable, though more so than the case A =40. If we accept 
A3, and if its atomic weight is consequently about 14, argon 
would appear as a condensed nitrogen, N3. In favour of 
this view speaks the common existence of argon and ni- 
trogen in Nature ; many lines of their speAra fall very 
near to each other, and the inert chara^er of argon is 
intelligible if formed from Na with liberation of heat, and 
lastly, its formation from chemical nitrogen. This hypo- 
thesis, that A B N3, might be tested by the introduaion 
of boron or titanium into an atmosphere of argon through 
which eledirlc sparks are caused to strike, and with strong 
heating. 

If we assume A4 or A5 the atomic weight of argon 
would be s 10 or 8, and it would find no place in the 
periodic system. If we finally accept A6, and assume 
6 atoms in a mol. of arf^on, there results an atomic weight 
of about 6*5, and the element falls in the first series, pro- 
bably in the fifth group. 

Hence the two most probable assumptions are:— 
I. That argon is a polymer of nitrogen a N3. 2. That 
the argon molecule is hexatomic, of course admitting 
that it is a pure elementary substance. 

A. Gorbow remarks that the chemical inertness of argon 
is possibly due to its absolute dryness, since its discoverers 
have always dried it with PzOy He is of opinion that 
argon is possibly a nitrogen compound, ^.^., nitrogen 
silicide.— Atfma;i Physico-Chemical Sociityt 1895, PP- ^7 
to 20, and JSiiL Anorg» Chemit, 



ON ARGON. 
By D. MBNDELBBFF. 



COMPARISON BETWEEN THE SPECTRA OF 

THE GAS OF CLEVEITE 

AND OF THE SOLAR ATMOSPHERE. 

By H. DBSLANDRES. 



Is argon a chemical individual or a mixture ? is it a 
simple or a complex body ? Mendeleeff replies as fol- 
lows : — ^The assumption that argon is a mixture appears 
quite improbable, as is especially shown by the experi- 
ments 01 Olszewski. The assumption of the composite 
charaAerof argon has also little probability, though its 
exceptional stability is to a certain extent charadleristic 
of some compounds. If we accept argon as an element, 
and further assume that its molecular weight is — 40, we 
must discuss a series of suppositions as to the atomic 
weight of this substance, which will evidently depend on 
the number of atoms in the molecule of argon corre- 
sponding to the series A, Aa, A3, . . . A». To the first 
case there would correspond an atomic weight of about 
40, when argon would appear as a monatomic element 
and as an analogue of Cd and Hg. For this view we 
have the relation K of the specific heats, which for argon 
has been found a x*66. We must, however, consider 
that for the biatomic molecule of chlorine K a 1*3 in- 
stead of 1*4. If so adive an element as chlorine possesses 
a smaller K, the extremely inactive argon must have a 
greater K, although its mol. consists of two or more 
atoms. For the atomic weight A » 40 there is no corre- 
sponding place in the periodic system. If the density of 
argon is below 20, it would come, according to its atomic 
weight, between chlorine and potassium, and must find 
its place in the eighth group of the third series ; though 
in this series the existence of the eighth group is scarcely 



The great discovery, by Prof. Ramsay, of a method of 
obtaining the gas helium, previously recognised only in 
the sun*s atmosphere, equally interests astronomers and 
chemists. 

At the outset the gas of cllveite and the sun's atmo- 
sphere have been respectively identified merely by the 
yellow ray D3. which they emit strongly ; still the last 
communication irom Prof. Cleve seems to indicate other 
common radiations. I have therefore resolved to com- 
pare carefully the two lights over the greatest possible 
extent of the spedrum. 

A capillary spe<flral tube, closed with a plate of quartz, 
was prepared and arranged so as to receive the gases 
emitted by a small crystal of cl^veite, first heated and 
then brought in contact with pure rectified sulphuric acid. 
The spectra of the tube were accurately taken down be- 
fore heating, after heating, and after the aAion of the 
acid, so as to recognise the gases successively liberated 
and to eliminate alien lights. 

Before heating, the spe^ral tube, the pressure on which 
was about ^^ m m., showed some of the rays referred to 
argon ; then on heating (to about 300°; there was a plen- 
tiful liberation of an oxygen compound of carbon, appa- 
rently derived from a dissociated compound ; for when the 
heat was continued the interior pressure increased and 
diminished on allowing the tube to cool. The yellow ray 
Dj appeared only when the sOlphuric acid had been in 
conta^ with the cleveite, at the same time with other 
strong rays, luminous and ultra-violet. 

The author has collocated in a tab'e the strongest new 
rays with their intensities (from i to 10, xo signifying the 
strongest), and, in a parallel column, the rays already in- 



CitBUlCALNtWS,) 

July xa, 1895. f 



Determination of Sulphur in Cast Metal^ &c. 



15 



dicated by Prof. Cl^ve. He remarks, in a note, that after 
the ray D3 he has not detedted the rays announced by 
Mr. Crookes. Opposite the above he has placed the 
nearest rays of the solar chromosphere, as determined by 
Mr. Young in the luminous region and by himself in the 
ultra-violet region. The intensities are represented with 
a scale of i to xoo, and another column shows the fre- 
quency of these chromospheric rays, i.«., the number of 
times that they occurred in the atmosphere in xoo obser- 
vations. The rays which occur always are thus followed 
by the number too ; they are called permanent rays. They 
are not numerous, as we find only 11 in the luminous 
region, 5 being due to hydrogen and 2 to calcium. The 
four others, among which is the ray Dj, are not referred 
to known elements. 

The gas of cl^veite emits, therefore, besides the ray D3, 
several other strong rays of the chromosphere, and in 
particular the ray 447*18, which is permanent, so that the 
number of the sun's permanent rays not recognised upon 
the earth is reduced to two. 

Lastly, other strong rays of cl^veite, such as the green 
ray \ 501-60 and the ultra-violet ray \ 3888, have in the 
sun's atmosphere neither the same relative intensity nor 
the same frequency as the ray D3 ; thus we are led to 
think that the gas is a mixture or a compound. 

I will mention two other fads in support of this 
opinion : — 

' The ray D3 in the speAral tube is seen only in the 
capillary part and at the positive pole ; it is wanting at 
the negative pole, whilst the green ray \ 501 is there very 
brilliant. 

Lastly, Prof. Lockyer has found, in broggerite, a mine- 
ral closely allied to cliveite, only a part of the foregoing 
rays. — Comptes Rendut, cxx., p. xiza. 



I 



DETERMINATION OF SULPHUR IN CAST- 
METAL, IN STEELS, AND IRON. 
By LOUIS CAMPREDON. 

Principles 0^ the Method, 
I. Liberation of the sulphur in the form of gaseous 
compounds, by attacking the metal with dilute hydro- 
chloric and sulphuric acids. 

2. Passage of the gases, with the addition of carbonic 
.acid and hydrogen, into a tube of porcelain heated to 
-redness, according to the indications of Rollet to trans- 
form the sulphurous compounds disengaged into hydrogen 
sulphide. 

3. Causing the gas to bubble through a slightly acid 
solution of zinc acetate, to retain the hydrogen sulphide 
in the state of zinc sulphide insoluble in weak acetic acid. 

4. Sulphydrometric titration of the zinc sulphide formed 
by means of a standard solution of iodine and a solution 
of sodium thiosulphate, to determine the quantity of 
iodine present in excess. The end of the reaaion is 
marked by the very distind disappearance of the blue 
colour of the solution in presence of starch (added as 
indicator), when no trace of free iodine remains. 

The zinc sulphide formed, submitted to the adion of 
an excess of iodine, gives ZnS-l-I = ZnI-f-S. 

This reaaion, the exaditude of which has been veri- 
fied, if efieded in a neutral liquid or in an acid liquid 
without adion upon the zinc sulphide. 

Description of the Apparatus. 
It includes two continuous appliances for the produc- 
tion of carbonic acid and hydrogen. These gases pass 
-into a solution of silver nitrate, to hold back the sul- 
phuretted compounds which they may contain ; they then 
anive in the solution flask, where they mix with the 
gaseous produds resulting from the adion of the acid 
employed upon the metal. The gases are cooled by their 



passage into a condensing flask immersed in water, and 
which retains the greater part of the Watery vapour. 
The gaseous mixture then traverses a tube of porcelain 
heated to orange redness or to incipient whiteness, and 
bubble into a Durand flask containing xoo c.c. of solution 
of zinc acetate, prepared according to the diredions given 
below. Finally, the gases traverse a solution of lead 
acetate (slightly acidified with nitric acid), which must 
not be rendered turbid by the passage of the easeout 
current, thus proving that all the hydrogen sulphide hat 
been kept back. 

Method of Manipulation, 

We operate upon 2, 5, or xo grs. of the metal, according 
to its supposed proportion of sulphur. 

The apparatus having been fitted up, as shown above 
(the current of carbonic acid being established and 
that of hydrogen arrested), we introduce the metal in 
fine filings into the solution flask, taking all the 
due proportions to avoid the formation of an explosive 
mixture, for which purpose it is suflicient to maintain in 
the tube, at the beginning of the operation, an atmosphere 
of carbonic acid. 

The stopper of the solution flask is inserted, and we 
introduce, by means of a tube-funnel fitted with a cock, 
100 c.c. of sulphuric acid at i : 5, or of hydrochloric acid 
at 1 : 3. The adion is kept up in the cold for two or three 
minutes, still maintaining the stream of carbonic acid ; 
heat is then applied, and the current of hydrogen is 
allowed to enter. 

In the first Durand flask there is formed a white floe* 
culent precipitate of zinc sulphide. 

When the readion is completed we remove the conical 
solution flask, as also the first Durand flask containing 
the zinc sulphide. The tubulures are washed by means 
of a jet from the washing-bottle, to remove any adhering 
portions of sulphide, and we separate the tubulure. The 
titration is eflfeaed in the Durand flask itself, so as to 
dispense with any transfer of the precipitate. 

We add, from a burette, a known quantity of iodine, 
more than sufficient to decompose the zinc snlphide ac- 
cording to the equation indicated above; we leave the 
reagents in contaA for two or three minutes, stirring the 
mixture, and then add 2 c.c. of liquid starch-paste, which 
produces a greenish colouration. We then run into the 
flask from a burette, stirring the liquid gently, sodium 
thiosulphate, until the colouration — which was at first 
deep green and then indigo-blue— disappears entirely. 
The iodine aAing upon the sodium thiosulphate in pre- 
sence of water produces sodium tetrathionate and hydri- 
odic acid. 

Preparation of the Solutions, 
X. Zinc Acetic Solution, — Dissolve 10 grms. pure 
zinc oxide in 25 c.c. of crystallisable acetic acid, dilute 
to about half a litre, add an excess of ammonia until the 
precipitate of oxide formed re- dissolves, and then render 
it slightly acid with acetic acid. 

2. Solution oj Iodine. — Dissolve 7*9 grms. of triply 
sublimed iodine and 25 grms. potassium iodine in i litre 
of water. 

According to the formula of the rea^ion^ 

HS -f I 
x6 127 
we see that— 

£i7 « 79 
x6 T' 

so that 7*9 grms. of iodine correspond to i gnn. of 
sulphur. 

3. Starch Liquor,^Take i grm. of wheat starch, pul- 
verise in a mortar, add a little water to obtain a thin 
paste, which is poured into a beaker of Bohemian glass 
containing 150 c.c. of boiling water ; let settle, and de- 
cant the clear liquid. 

Fresh starch liquor ought to be prepared daily. 



HI + S, 



i6 



Chemistry of the Lignocelluloses. 



1 July 12. 1895. 



4. Solution of Sodium ThiosulphaU. — Dissolve logrms. 
thioBulphate in water, adding 2 grms. ammonium car- 
bonate and water enough to make up x litre. The am- 
monium carbonate increases the stability of the thio- 
Bulphate. 

The iodine and the thiosulphate solutions are preserved 
in the dark in boiiles of yellow glass. 

Concluiion, 
The process just described is very expeditious ; the sul- 
phur is determined in thirty minutes at most. For cast 
metal 'he aAion must be prolonged a little, to make sure 
that it is complete. This we ascertain by changing the first 
Durand flaskj and substituting a second one containing a 
clear solution of zinc acetate. If in this second flask 
there is produced a precipitate of zinc sulphide, it is 
titrated like the former. — Comptes Rendus, cxx., X051. 



ON A NEW FORM OF CHEMICAL BALANCE. 
By H. JOSHUA PHILLIPS, F.I.C., F.C.S. 

Ths writer has recently been experimenting with hydro- 
meters, to ascertain to what extent they could be applied 
to adt as a chemical balance ; the result of which was, 
after several trials, the making of an instrument which 
for certain purposes will be found to be useful. The fol- 
lowing is a sketch and description of the instrument :— 



It consists of a glass cylinder upon the top of which 
can be fixed a portable brass ring containing two upright 
guide-Tods of brass, 6 inches high and J inch in diameter. 
The balance proper consists of gilded brass bulbs into 
which is screwed an aluminium stem. Screwed on to 
the top of the stem there are arms, also of aluminium, 
which are perforated at each end so that the guide-rods 
can pass through them. Upon the centre of the arms 
there is a receptacle for a small aluminium scoop or pan 
to hold the substance to be weighed. Underneath the 
arms it will be seen there are projeAing needle-points; 
there is also a movable point upon one of the guide-rods. 
The manner of using the instrument is as follows :— The 
cylinder is first filled with cold recently-boiled water; 
the bulbs and attachments are then dropped in, the 
guide-rods passing through the perforations of the arms. 
The balance sinks into the water until the bulbs are just 
covered. Supposing 0*2 grm. of steel drillings are desired 
to be weighed. A 0*2 grm. weight is dropped into the 
portable pan; the bulbs then sink to a definite depth, and 
which can be ascertained by bringing the movable needle- 
point upon the guide-rod so as to face the point fixed 
upon the arm. The weight is now taken off, and the 
bulbs rise again. The sample of steel drillings is now 
gradually introduced into the empty pan until the needle- 
points are again opposite each olberj— {jently tapping the 



instrument to remove any fridlion, — and the 0*2 grm. of 
steel is thus quickly obtained. The range of weight that 
such an instrument is capable of recording must of 
necessity be of narrow limits. The depth to which the 
instrument will sink in the liquid with a given weight, 
and also its delicacy, will depend upon the diameter of 
the stem. The diameter of the stem of the balance 
shown in the sketch is ^g inch, and a load of 0*2 grm. 
will sink it about 3I inches. The height of the cylinder 
is 10 inches, and its diameter xj inches, and the total 
length of the stem 5I inches. An instrument of these 
dimensions will be found useful for weighing steel for 
carbon tests, &c., and also for weighing certain precipi- 
tates, &c. The sole makers are Messrs. Townson and 
Mercer, of 89, Bishopsgate Street, London, E.C. 
PaUce Chambers, Wettmioster, S.W. 



CHEMISTRY OF THE LIGNOCELLULOSES: 

A NEW TYPE. 

By W. C. HANCOCK and O. W. DAHL. 

The pith-like stem ol Aeschynomtne Aspera* offers a very 
exceptional instance of wood formation. Although, from 
considerations of external resemblance, it is often described 
as a pith, its morphological charaderistics are those of a 
true wood (De Bary, ** Comparative Anatomy of the 
Phanerogams," p. 499). The readions of this wood- 
substance, on tlie other hand, show important exceptions 
from those characteristics of the lignocelluloses. Solutions 
of aniline salts and of phloroglucol in HCl give the 
faintest colouration only with the main mass of the 
cellular tissue, reading stronglv with only a few' cells 
situate near the central axis, and certain vessels disposed 
at intervals and concentrically in the radial line of cells. 

In this preliminary microscopical examination oar re- 
sults were confirmed by competent botanists, who 
described this wood as consisting in the main of cellulosic 
tissue, with a small proportion of lignified elements dis- 
posed as described. 

Having submitted the material to exhaustive chemical 
investigation on the lines laid down by Cross and Bevan 
(** Cellulose," p. 94), we find it to be a lignocellulose of 
normal constitution. Those readions and decompositions 
which are related to constitution are identically those of 
the typical members of the group. But these typical cha- 
raderistics are associated with divergence in minor points, 
and particularly in regard to the absence of those con- 
stituents upon which the colour-readions in question 
depend. It has previously been shown (Cross and Bevan, 
Chem. Soc. Traus,, 1883, p. x8) that the yellow readlion 
with aniline sulphate is a readlion of an aldehydic or 
quinonic by-produd. Thus the jute- fibre substance, after 
boiling in a solution of sulphite of soda, or when re-preci- 
pitated from solution in ZnCIa— Aq, no longer reads with 
aniline salts. 

Similarly the phloroglucol readion is that charaderistic 
of pentosanes, and is no doubt due to their presence in 
the majority of lignocelluloses. In the particular instance 
of Aeschynomtne we have a wood giving the large yield of 
furfural charad eristic of the group, but the pentosan re- 
adion only in scattered cells. 

The wood of Aeschynotnene affords, therefore, another 
and striking instance of furfural yielding constituents of 
tissues not pentosans {comp. Ber., X894, xo6i). 

The following are the results of experimental deter* 
minations of the more important reaAions and constants. 

Physical Characteristics, 
The cylindrical stems are made up chiefly of thin- 



* The pUnt is 00c of the Leguminosee, of aquatic habit, the wood 
being modified to serve at a float. The product has eztentive iodua- 
trial uses, e.g., in the raannfaAure of pith belmeti. See ** DiAiooary 
of Economic FroduA^ of India," Watt, vi., p. 125. 



July la, 1895. ' 



Chemistry 0/ the Lignocelluloses. 



17 



walled, air-filled cells ; i grm. of the substance having 
the enormous volume of 45 to 50 c.c. 

The substance in its natural form appears opaque 
white ; on compressing to denser masses it is seen to have 
a yellowish colour. 

Reactiont, 

With solution of aniline salt a faint yellow, giving the 
readion of the lignocelluloses only in isolated cells. 
With phloroglucol and HCl, a faint pink ; the full red 
colouration charaderistic of the lignocelluloses (pentosane 
constituents) in isolated cells only, as with the preceding 
reagent. 

With Schulze*8 solution (I in KI -f ZnCl2) a brown 
colouration, giving place to greenish-blue in washing. 

With a solution of iodine in strong aqueous hydriodic 
acid (1*5 sp'gr.) it it stained a pure blue, not removed by 
washing. 

The ordinary woods are stained purple-brown with 
t))is reagent, which is changed to brown on washing. In 
this reaSion, therefore, there is a decided resemblance to 
the celluloses. 

With the aniline colours the tissue is dyed in most 
cases uniformly. So also with ferric ferricyanide {infra). 
In this reaAion the tissue shows the distindive charader- 
istics of the lignocellulose group. 

The tissue, unlike the majority of lignocellulose?, does 
not reduce Fehltng*s solution on boiling. 

Composiiion, 

In the air-dry condition the substance retains only 8*6 
per cent moisture. The mineral constituents amount to 
1*9 percent. 

BUnuntary Analy sis. —Tht following results were ob- 
tained, calculated in the dry ash-free substance :— 

C •• •• 46*9 46'a 

H .. .. 7*1 6*4 

These numbers are approximately those of the jute fibre 
substance. 

Alkalint Hydrolysis. — On boiling with alkaline solu- 
tions (i per cent NaOH) the substance rapidly loses 29*0 
per cent of its weight. On prolonged boiling (60 minutes) 
the further adion of the alkali is only slight, the total 
loss of weight being 29*8 per cent. 

Cillulost. — After boiling with alkaline solutions as 
above, and washing, the substance gives with chlorine the 
ordinary reiidion of lignocelluloses, forming a yellow 
quinone chloride, dissolved by sodium sulphite (sol.) to a 
deeply coloured solution. The cellulose isolated by this 
treatment amounted to 54*4 per cent. 

Constants of Chlorination, 
Determinations were made of the volume of chlorine 
absorbed in the above readion, and of the hydrochloric 
acid formed ; the quantities being calculated to the re- 
duced weight of the produd, t. r., the weight after boiling 
with the alkaline solution (Cross and Bevan, Chem, SoCt 
55> 199)* 
{a,) Weight of wood, 1*24 grms. ; reduced weight, 
0*966 grm* 
Conditions : Moist CI gas at 21*5" and 760 m.m. 
Tine in minutes: o 5 10 15 ao 25 40 50 60 210. 
C.c. gas absorbed : o 44 55 60 64 66 70 72 79 94. 
Total absorption calculated to chlorine at o", 760 
m.m.~84'5 cc. 
(6.) Weight of substance, 2*062 grms.; reduced weight, 
x*6io grms. 
Conditions : Moist CI gas at 19*5* and 766 m.m. 
Time in minutes : 0*5 xo 15 20 25 30 35 40 50 60. 
C.c. gas absorbed : 0*71 79 86 91 95 97 98 99 X02 

X06. 
Total absorption calculated to CI at o^ 760 m.m. 
-93-3 c.c. 
The main readion reaches its limit after about thirty 
minutes* exposure) the subsequent exposure is due to 



secondary readions, attended by decompositions of thd 
chlorinated derivatives. 

This conclusion is confirmed by the following deter* 
minations : — 

(«) (*.) 

Chlorine as HCl formed in 

the readion 0*1526 grm. 0*1278 gnu. 

Chlorine in combination with 

wood constituents • • . . 0*0750 0*1633 

Total chlorine .. •• 0*2276 0*29x2 

Total CI estimated by 
absorption 0*2782 0*2964 

It is evident that the abnormal figures of experiment (a) 
are due to the prolonged exposure of the substance to 
the halogen. 

Taking the figures for the total absorption after thirty 
minutes* exposure to the gas, when the main readion 
may be regarded as completed, they are, calculated 00 the! 
weight of the lignocellulose taken : in (a) 20 per cent, in 
{b) 16 per cent ; mean 28*55 P^r cent. 

The combined chlorine estimated in (6), also calculated 
on the lignocellulose, is xo per cent. This readion, 
therefore, is shown to be that generally charaderistic of 
the lignocelluloses; the quantitative results being inter- 
mediate between those obtained for the jute fibre, on the 
one hand, and the woods on the other (** Cellulose," 
p. 180). 

Furfural, 

The furfural constants, determined by the method of 
Flint and Tollens {Landw, Vtrs. Stat,, xlii., 381). The 
furfural was estimated in the entire wood substance, and 
also in the produds of the alkaline hydrolysis. Results 
were as follows :— 

Poifara]. 

Whole wood substance • •• •• xx'6p.c. 

Produds of alkaline hydrolysis, soluble •• 3*6 
f, I, „ insoluble. • 8*0 

Of the total furfuroids, therefore, 69 per cent remain in 
the residue unattacked by the alkaline solution. As the 
proportion of residue is 70 per cent of the original wood 
(supra), it will be seen that the ratio to the other consti- 
tuents, or, in short, the distribution of the furfuroids, is 
unaffeded by the alkaline treatment. The furfuroids 
therefore are not present as pentosanes, or at least are in 
small proportion. 

Methoxyl, 

The substance was treated according to the method of 
Zeisel : OCH3 estimated =« 2*9 per cent, calculated on 
the dry ash-free substance. This number is considerably 
less than for the woods generally, and 20 per cent less 
than for jute. (See Benedikt and Bamberger, Monatsheft, 
ii., 260—267.) 

Ftrrie Ftrricyanidt Reaction, 
The readion of the lignocelluloses with the solution, 
obtained by mixing ferric chloride with potassium ferri- 
cyanide in equivalent proportions, is a distinguishing 
charaderistic ; and the wood of Aeschynomtm gives an 
equally pronounced readion, being dyed evenly to the 
deepest colour with a very large increase of weight, due 
to the fixation of the ferroso-ferric cyanide. The following* 
results were obtained :— 

(a.) X grm. lignocellulose increased to 1*958 grms. 

(*•) I 1. I. It 1747 M 

the lignocellulose being boiled in water to expel air, and 
digested some hours with excess of solution of ferric- 
ferricyanide, obtained by mixing normal solution of 
FeaCle and K3Fe(CN)6 in equal volumes. The gain in 
weight, due to absorption of the blue cyanides, ex- 
ceeds xoo per cent, calculated on the dry aah-ftve ligno- 
cellulose. 
In the resulting produds the Fe was determiMd u 



18 



Revision of the A tomic Weight of Strontium. 



! CHtmcAL Ntwk, 
I July X2, 1895. 



FeaOj and the N as NH3, and the molecular ratio Fe : CN 
found to be 1 : 2*4. The blue cyanide fixed by the ligno- 
cellulose has the co.:^ position Fe5(CN)x2* 

Nitrates. 
The substance shows the usual readion of the ligno- 
celluloses with nitric acid in presence of sulphuric acid. 
It is coloured 10 a red-brown, which gives place to a 
bright yellow on washing. It gives low yields of nitrate 
(ixo per cent), and in this respeA is shown to be consti- 
tutionally more really related to the woods than to the 
fibrous lignocelluloses. The nitrates, moreover, contain 
a low proportion of O.NO2 groups, yielding on analysis 
N a 7— 9 per cent— and are insoluble in the usual solvents 
of these compounds. 

Tkiocarhonate Rtaction {J, Chem»Soc.t 1893,837). 
The lignocellulose yidds to a certain extent to the joint 
adion of the caustic alkalis and carbon disulphide, the 
reaAion which ensues resembling that of the jute fibre. 

The substance is gelatinised, but only a small propor- 
tion — 20 to 30 per cent of its weight — passes into 
solution when treated with water. This affords addi- 
tional evidence of the small proportion of free alcoholic 
OH groups. 

By the foregoing results this peculiar produd of growth 
is completely identified as a lignocellulose. To botanists 
tnis identification will have a special significance as pre- 
senting a type of lignification of unique charaderistics. 
Regarded from the chemical point of view, the most im- 
portant points established and confirmed are : — 

X. The existence of a lignocellulose having the essen- 
tial constitutional features of the group, but devoid 
of free aldehydic groups and charadlerised by colour 
readions, which are only in part those of the ligno- 
celluloses generally ; in others showing a close 
resemblance to the celluloses. 
2. Certain colour reactions, frequently regarded as es- 
sentially charaderistic of the lignocelluloses proper, 
are in efled due to by-produds. 
' 3. Owing to the unusual conditions of growth, and 
metabolism obtaining in a tissue, specialised to 
lerve an exceptional fundion, these by-produds are 
not formed in a large proportion of the cells, which 
are nevertheless shown to consist of true ligno- 
celluloses. . 
4. That the true lignocelluloses contain furfural-yielding 
constituents— furfuroids— which are not pentosans. 
Note. — We are indebted to the authorities of the 
Imperial Institute for a liberal supply of the raw material^ 

Laborttoryof Menrs. CroM and Bevan, 
London, W.C. 



A REVISION OF THE ATOMIC WEIGHT OF 

STRONTIUM. 

First Paper : The Analysis of Strontic Bromide.* 

By THEODORE WILLIAM RICHARDS. 

Earlier Work, 
A GLANCE at published results shows that the atomic 
weight of strontium has not been investigated for thirty* 
five years. The early determinationsi eood enough for 
their time, show variations which render them quite un- 
satisfadory to-day ; and the case is parallel in every 
resped to that of barium, which has formed the subjed 
of two recent papers (Proc, Amer, Acad.^ xxviii., i; 

xxix.i 55 ^« 

The oldest experiments of any note upon the atomic 
weight of strontium are those of Stromcycr [Schteeig, y., 

^ Contributioos from the Chemical Laboratory of Harvard Col- 
lege. Proro the Frocetdingi of the AmericaH Academy. 



xix., 228; Meyer u. K. Seubert*^ " Atomgewichte," p. 123), 
who measured, in x8i6, the gas evolved from strontic 
carbonate upon its decomposition by an acid. The result, 
which is only of interest historically, gives Sr ^ 873, if 
a litre of carbon dioxide weighs 1*977 gnns* under normal 
conditions. 

At about the same time Rose (Poggendorjps AnnaUut 
viii., i8g) found that 181*25 parts of argentic chloride 
could be obtained from 100 parts of strontic chloride,— 
data which indicated Sr « 87*31. Twenty-seven years 
afterward, in 1843, Salvetat {Comptes Rendus, xvii., 318) 
determined by loss of weight the carbon dioxide in strontic 
carbonate, and concluded that the metal must be 88*0,— 
a result which scarcely improved the situation. 

Subsequently, in 1845, Pelouze (/6i<f., xx., X047) found 
the amount of silver necessary to precipitate a weighed 
amount of ignited strontic chloride ; his results give the 
value Srs 87*70. Thirteen years later Marignac {Liehig'i 
Annalen, cvi., z68) repeated these experiments, deter- 
mining also the amount of crystal water in crystallised 
strontic chloride, as well as the amount of strontic sul- 
phate obtainable from the salt. Thus he found that 
15*000 grms. of crystallised strontic chloride yielded 
89164 grms. (correded by L. Meyer u. K. Seubert, 
" Atomgewichte," pp. 78, 79) of the anhydrous salt and 
10*3282 grms. of strontic sulphate; moreover, 15*000 
grms. of hydrated strontic chloride required 12*1515 grms. 
of silver for precipitation. Another similar series of ex- 
periments upon the water of crystallisation made its 
amount appear 3 m.grms. more than before. These data 
give basis for a number of possible values for the atomic 
weight of strontium, ranging from 87*17 to 87*55, ^^^ ^^^^* 
vidual figures being tabulated below. 

In 1859 Dumas {Liebig^s Annalen, cxiii., 34) published 
another determination of the ratio of strontic cnloride to 
silver, the salt having been fused in a stream of hydro- 
chloric acid. Altogether, 27*3435 grms. of strontic 
chloride required in his hands 37*252 grms. of silver, the 
individual values for strontium varying from 87*3 to 87*8. 
Since this time the subjedt has remained untouched. 

Below is tabulated a list of the various determinations, 
grouped according to the ratios determined. 

The Atomic Weight of Strontium. 
Oxygen » 16*000. 

From the carbonate : — 

Stromeyer, 1816 • 87*30 

Salvetat, 2843 8S*oo 

Ratio of strontic and argentic chlorides: — 
Rose, 18 16 ? 87*31 

Ratio of anhydrous strontic chloride to silver : — 

Pelouze, 1845 87*70 

Marignac, 1858 87*48 

Dumas, 1859 87*53 

Ratio of crystallised strontic chloride to silver :— 
Marignac, 1858 87*52 

From the crystal water in strontic chloride: — 
Marignac, 1858 8735 

Ratio of anhydrous and crystallised strontic chloride to 
strontic sulphate :— 

Marignac, 1858 •• •• 87*2 to 87*6 
SeleAed by Clarke . . • . 87*58 
Seleaed by Meyer and Seubert 87*5 
Sele^cd by Ostwald*. . . . 87*5 

A critical review of the list reveals a great lack of 
trustworthiness in all the figures. The values deduced 
from the carbonate, and those involving water of crystal- 
lisation, may all be thrown out at once ; and the results 
yielded by the displacement of hydrochloric by sulphuric 
acid are but little better. The series upon which most 



* Much assistance in preparing this list has been obta'ned from 
the well-known works of these authors. The figures have all been 
based upon the most recently accepted atomic weights. 



1 



CttSMICALNtirtyl 

Jnljr 12, 1895. f 



RevMon 0' the AtonUc Weight of Strontium. 



chemists have relied— the one based on the titration of 
the chloride by means of silver— is hopelessly vitiated by 
the imperfed execatioo of the method of analysis {Proc, 
Amtr, Aead.f xxix., 80 et stq,). If any farther proof of 
this uncertainty were needed, the following table, giving 
a comparison of the work of different experimenters upon 
other chlorides, would furnish it :— 

MoUcular Wtight of Chhridts by the Method of 
Gay-L 



NaCl , 
KCl . 
NH4CI < 



PeloiiM. 
53*4^4 



'Lussac. 
Ilarifiuc. Damn. 

— 58468 

74*539 — 

53450 — 



Stai. 
tat. 2nd. 

58*506 58-503 
74*583 74600 
53530 53532 



Thus Pelouxe, Marignac, and Dumas all obtained low 
results with the method of Gay-Lussac ; in fad, the error 
sometimes exceeded the tenth of i per cent. The cause 
of this error, which appeared also in the work of these 
experimenters upon barium, has already been pointed out 
in another paper {Proc. Amer, Acad., xxxix., 80.). 

We are thus led to infer that the true molecular weight 
of strontic chloride must exceed the uf ually accepted 
▼alue, I58'4, by about one-tenth of i per cent, and that 
the true atomic weight of strontium must be nearly 877. 
This inference is confirmed by the result of the investi- 
gation now to be described. 

The balance and weights, and the methods of weighing 
and of tabulating results employed in the work recounted 
below have already been described in sufficient detail 
iProe. Amir. Aead.t xxvi., 242; also xxviii., 5). The 
balance seems to have increased slightly in sensitiveness 
during its four years* work, owing perhaps to the smooth- 
ing of microscopic roughnesses in the bearings. It is 
almost needless to say a^ain that the weights were care- 
fully standardised from time to time, and the small, sur- 
prisingly constant corrections were alwa3rs applied. The 
corredion to the vacuum standard was calculated by the 
asoal formula :^ 



( "^"93 - 0000156) -5 
\8p. gr. substance / 700 



273' 



7^ 273°+!*' 

•B corredion in grms. for i grm. of substance.* 

The values thus calculated for the appropriate sub- 
waaces at ao* and 760 m.m., were as follows :— 

Comction to be Applied to One Orm. of Substance. 

Silver ' -0*000031 grm. 

Argentic bromide . . . . +0*000043 „ 
Strontic bromide .. .. +o'ooox4X „ 

The general plan of the following work was similar to 
that adopted in the case of barium. For obvious reasons 
the bromide of strontium was chosen as the starting- 
point ; and the investigation began with a study of the 
properties of the salt, in order to determine its fitness for 
the purpose. 

The atomic weight of silver is assumed to be 107*93, 
snd that of bromine 79'955t unless a definite statement to 
the contrary is made. 

PfOperH$s of Strontic Bromide, 
The • properties of the bromide of strontium resemble 
very ck>sely those of the corresponding salt of barium. 
As is well known, however, the strontium salt usually 
crystallises with six instead of with two molecules of 
w^ter. The crystals, unlike those of the barium salt, are 
_,^ siticeably hygroscopic in ordinary air, so that they can- 
icwho^t be weighed with great accuracy ; they melt easily in 
Atiustr*^ own water of crystallisation at about 100*. This 
IfcboOter faa renders more difficult the quantitative drying 

•fi^^K »l «* fctmotpheric prcraare ; r^rtmoipherk temperatnre «t the 
r, e ot weigh.ng ) 0000136 « ttaoiUtd weight of air ditplaced by 



J9^ 

of the salts ; indeed, in the few cases where the water of 
, crystallisation was determined, it was necessary to allow 
I the crystals slowly to lose their water in a desiccator be- 
I fore ignition. Thus it was found in the following experi- 
ment that five molecules of water were given off, the 
sixth having very little, if any, tension at ordinary tem- 
peratures. 

Grms. 
Initial weight of strontic bromide .. .. X'3305 
Constant weight after three weeks over 

H2SO4 0*9926 

Heated to 200^ for three hours . . • • . . 0*9246 

Loss of weight in dry air, found .. •••* 25*41 

M •• M calc. for 5HaO -25*33 

Additional loss on ignition, found •• •• « 5*11 

M M If calc •« 5*o6 

A week's standing in the air of the laboratory sufficed 
to supply again all the water which had been lost. These 
results point without doubt to the existence of a definite 
substance having the formula SrBra. HjO, which is hygro- 
scopic in the air and corresponds to the compound 
BaBra . HjO, obtained in a similar way {Proc. Am. Acad., 
xxviii., 12, footnote). The existence of this substance has 
already been inferred by Lescoeur (^fi. de Chim. et dePhys. 
[6] ,xix., 553, 1890) from observations of the vapour tension 
of the crystal water. Anhydrous strontic bromide is per- 
haps even more hygroscopic than the corresponding salt 
of barium. 

Strontic bromide melts to a transparent liquid at 630° 
(Carnelley), losing bromine in noticeable.quantities if ex- 
posed to the air for some time at this temperature. Fused 
m a current of dry hydrobromic acid the salt soon 
recovers this lost bromine, and upon subsequent solution 
in water shows itself to be wholly neutral both to phenol- 
phthalein and to methyl orange. It will be seen that this 
faA is of the utmost significance. The cold fused trans- 
parent or translucent mass is much less hygroscopic than 
the powder from which it was made. 

The importance of driving out every trace, of water 
from the salt before weighing cannot l>e .over-estimated. 
Systematic experiments (Proc. Amer. Acad., xxviii., 12 ; 
xxix., 58) with baric bromide and chloride led to the con- 
clusion that probably neither of these salts retains water 
at a red-heat, and it was to be exi>eded that the same 
fa^ might be true of the substance in hand. In order to 
test the point, 4 grms. of very pure strontic bromide dried 
at about 400° were fused in a stream of hydrogen bromide. 
The mass gained nearly 6 m.grms. in weight, showing 
that the loss of bromine in the air at 400° much more 
than counterbalanced a possible trace of water. Again, 
XI '2610 grms. of the same specimen, dried at 305^ until 
constant in weisht, were found to wei^h 11 "2630 grms. 
after fusion as before. Since these gains corresponded 
closely with losses of bromine found alkalimetrically io 
similarly heated but unfused samples, it is evident that 
very little if any water can be held by the dried salt. It 
has already been pointed out that no absolute proof of 
such a U€t is possible {Proc. Amer. Acad, xxviii., 14) ; and 
these experiments, together with the analogy furnished by 
the more manageable barium salts, seem to be the last 
resort. The apparatus used for these experiments will be 
described under the heading '* Method of Analysis.*' 

The specific pavity of anhydrous strontic bromide has 
been found by Bddeker to be 3*96. Since no more recent 
data regarding this constant could be found, another 
determination, described below, seemed to be needed. 
3*2560 grms. of a pure specimen which had been fmed in 
the air and dried at 200° in the pycnometer were found to 
displace 06678 grm. of toluol at 24°. Since the specific 
gravity of the toluol under these conditions, referred to 
water at 4*, was found to be 0*8618, that of the strontic 
bromide referred to the same standard must be 4*203. 
Again, 2*3065 grms. of strontic bromide which had been 
used in a stream of hydrobromic acid displaced 0*4699 
grm. of toluol, thus having a specific gravity ol 4*229. 



26 



Electric Properties of Selenium. 



t CbKMICAL NiW8) 

1 Jaljf 12, 1893. 



The mean of these determinations, 4*216, was adopted as 
the basis of the reda^ion of the weighings to the vacuum 
standard. 

Strontic bromide, like baric bromide and chloride, may 
be evaporated to apparent dryness over a free flame in a 
platinum dish without losing a trace of halogen. Experi- 
ment showed that, upon mixing pure bromide of strontium 
with small quantities of bromide of calcium and barium 
and crystalfising the mixture, both impurities tended 
toward the mother liquors. Hence simple crystallisation 
affords a method of diminating tire two most likely im- 
purities. 

The other properties of strontic bromide do not pertain 
especially to the present work. 

(To be continaed.) 



PROCEEDINGS OF SOCIETIES. 

PHYSICAL SOCIETY. 
Ordinary Met ting , yunt 28fA, 1895. 

Dr. Gladstone, Vice-President, in the Chair. 

Mr. BowDEN read a note on ** An Electro'htagnttic 
BffecV 

A long glass tube containing mercury, and fitted with a 
small stand-pipe to indicate the hydrostatic pressure, is 
passed between the poles of an eledro-magnet. On 
passing a current of about 30 amperes through the mer- 
curt in this tube, the stand-pipe being turned so as to 
indicate the pressure either perpendicular or parallel to 
the lines of force of the field of the eleAro-magnet, 
movements of the mercury in the stand-pipe take place. 
When the stand-pipe is perpendicular to the lines of force 
of the field, the mercuryfrises or falls according to the 
diredion of the current. When the stand-pipe, however, 
is parallel to the lines of force, the mercury always r'nes 
whatever the diredion of the current. 

Prof. S. P. Thompson said there appeared to be three 
tinexplained effeds^ne proportional to the current and 
the field, and reversible ; another, independent of the di- 
redion of the current or of the field ; and a third, which 
only occurred while the current was changing in strength. 
In addition there may be a fourth effed, which up to now 
has not been noticed. The motion of the mercury column 
ill Fig. I was in the opposite diredion to that of the drag 
On a condudor carrying the current. An apparent rise in 
pressure might be due to a decrease in the density of the 
mercury due to the heat developed by the current. 

Mr. Blakbsley a^ked if the author had noticed any 
changes in level in the mercury reservoirs at the ends 
of the tube. 

The author, in his reply, said the reservoirs at the 
ends were so large that no changes of level were appre- 
ciable. 

Mr. Rhodes read a paper on <* Tht Armature Reaction 
on a Single Phase Alternating Current Machine.** 

In this paper the author gives the investigations that 
were the subjedl of a verbal addendum to a paper read 
before the Society on a previous occasion. He investi- 
gates the lag or lead of the E.M.F.'s over the current, 
and applies the results to examine whether the field ex- 
citation of the generator or the motor is strengthened or 
weakened by the readion of the armature currents. 

Mr. TuNZSLMANN expressed a hope that the author 
would amplify parts of his paper. 

Mr. Blakbsley said the conclusion of the author, that 
** either of two alternate current machines may be driven 
as a motor by the other, irrespedive of their relative 
E.M F.*8,*' is not invariably corred. The fads of the case 
were these:— The E.M.F. of the motor may exceed that 



of the other machine to a certain extent ; but that E.M.F. 
multiplied by the cosine of the angle of eledric lag must 
yield a produd not greater than the E.M.F. of the gene- 
rator, — i. e.t using Mr. Rhodes's symbols, e cos $ must not 
be greater than E. Mr. Blakesley gave a geometrical 
proof of this ; but the same proposition had been given 
by him some ten years ago, in the course of investigating 
the subjed generally. This was at a time when Dr. 
John Hopkinson was, with less than his usual perspicuity, 
teaching that synchronous alternate current machines 
could not be run in series with stability, both doing work. 
Referring to the author*8 diagrams, Mr. Blakesley said 
that in a problem involving so many elements' as that 
under consideration, it was impossible, with the limited 
dimensions of space, to represent the results with the 
complete generality of a formula. Some elements had to 
be taken as the independent, others as the dependent, 
variables. The author had considered the power trans- 
mitted to the motor, the E.M.F. of the generator, and the 
angle of eledric lag, as independent ; the E.M.F. of the 
motor as dependent. In Mr. Blakesley's original dia- 
grams the E.M.F. *s were both considered independent, as 
well as the eledric lag, and the powers applied or trans- 
mitted as dependent variables. In any case the formuls 
properly derived from such diagrams became perfedly 
general, and it did not appear to him that the change of 
method indicated could properly be called a new theory 
on the subjed. As a matter of fad, diagrams based on 
the independence of the E.M.F.'s and the eledric lag would 
furnish a better means of discussing the question of the 
stability of the motion than Mr. Rhodes*s plan, and this 
might account for the. entire omission from the paper of 
this important matter! 

Prof. S. P. Thompson said it was impossible to discuss 
the question of stability till the subjed of armature re- 
adion had been thoroughly investigated. The terms lag 
and lead had been used by Mr. Rhodes in a constant 
manner; but this was not always done, and he recom- 
mended that the phase of the current which was common 
to both generator and motor be taken as the standard. 

The author, in his reply, said he agreed with Mr. 
Blakesley that there was a limit to the extent to which 
the motor might be excited, and this upper limit could 
easily be obtained from the figure given in the paper. 
The question of armature readion was, however, most 
important, as it might excite the field two or three times- 
more than the original excitation. Since motors were de- 
signed to do a certain amount of work, and not the work 
to fit the motor, it was most natural to take the output of 
the motor as fixed. 

Mr. Shelford Bidwell read a paper on '* The Elec* 
trical Properties of Selenium" 

The author has continued his investigations on this 
subjed, and has come to the following conclusions: — 
(x). The condudivity of crystalline Se appears to depend 
principally on the impurities which it contains in the 
form of metallic selenides. It may be that the selenides 
condud eledrolytically, and that the influence of light in 
increasing the condudivity is to be attributed to its pro- 
perty of facilitating the combination of Se with metals 
in contad with it. (2). A Se cell having platinum elec- 
trodes and made with Se to which about 3 per cent of 
cuprous selenide has been added, is, even thou|^h un- 
annealed, greatly superior both in condudivity and 
sensitiveness to a similar cell made with ordinary Se and 
annealed for several hours. (3). Red Se in contad with 
copper or brass is quickly darkened by the adion of light, 
owin^, it is suggested, to the formation of a selenidtj. 
(4). Crystalline Se is porous, and absorbs moisture fro{|8 
the air, and it is this moisture that causes the polarisatiojc 
of Se after the passage of a current. (5). The preseni^t 
of moisture is not essential to sensitiveness, but appeaC- 
to be in a slight degree favourable to it. (6). If cuprobm 
selenide is made the kathode in an eledrolytic cell, andpa 
strip of platinum the anode in water, red Se mixed wi^ 



01ICM1C41. MlWl, I 

Joly I a, ii95. • 



'John Dallon and the Rise of Modern Chemistry. 



21 



detached particles of the selenide is deposited in the 
water. (7). The photo-eledric currents sometimes set up 
when lignt falls upon Se are dependent upon the presence 
of moisture, and are no donbt of voltaic origin. (8). Per- 
.feAly dry Se is below platinum in the thermo-eledric 
series. 

Prof. MiNCHiN (communicated) suggested that the 
selenium *'cell,'* should be called a selenium "resistance." 
A grid having one terminal made of aluminium and the 
other of copper might form a true cell, and might gene- 
rate an E.M.F. when light fell on it. He (Prof. Minchin) 
would like to know if the author had tried any such cell 
in which light, simply and solely, generated an E M.F. 
He could not agree that chemical aSion must necessarily 
foHow the aAion of light in a cell. For take the case of 
the oldest photo-eleAric 'cell, — the thermopile, — what 
chemical adion can we show here for all the energy of 
the incident heat ? Chemical aAion due to light may or 
may qot occur, according to the nature of the cell. 

Mr. Applbyard asked whether the author had submit- 
ted these selenium resistances to the adlion of elediric 
osdllatioos. Prof. Minchin*8 ** impulsion ** cells were 
greatly influenced by eleAric oscillations. The great 
variation in the resistance with time of the author's cells 
pointed rather to an effed of contact between the sele- 
nium and the eleArodes than to an elementary change in 
the struAure or composition. He (Mr. Appleyard) had 
recently tried to crystallise a supersaturated solution of 
sodium sulphate by elcdric oscillations, as well as by 
dired sparks, and by currents of several amperes ; but no 
crystals could be induced to form. Change of contaA 
rather than change of strudlure appeared to him to be the 
most promising dire^ion in which to look for an adequate 
theory of selenium resistances. 

Prof. Ramsay said the quantity of Se liberated in the 
eleArolvtic experiment was much too great to be ac- 
cotintcd for by oxygen dissolved in the water. The study 
of Se was very interesting, for this substance was on the 
border-land between those bodies in which the eledric 
coodoAion was metallic and those in which it was known 
to be eleArolytic. 

The author, in his reply, said he agreed that the name 
** selentum cell " was not an appropriate one. He had 
not tried the effed of eledric oscillations. 

The Society then adjourned till the autumn. 



NOTICES OF BOOKS. 

Tk€ Cimtury Scitnet Strits. jfohn Dalton and th$ Risi 0} 
Uodtm Chimistry, By Sir Hbnry E. Roscob, D.C.L., 
LL.D., F.R.S. London, Paris, and Melbourne : Cassell 
and Co., Ltd. 1895. 
Thb position of Dalton in the history of science is now 
so fully established and so universally conceded that it 
reqairea no discussion, especially as his career has been 
alreadv described by W. C. Henry, R. A. Smith, H. Lons- 
dale, J. Harland, C. Wheeler, and F. Espinasse. 

The author pronounces Dalton to be the *' founder of 
modern chemistry,'* and Joule to be the " founder of 
modern physics.'* 

Bat it is strange that thes^ two illustrious savants are 
pronounced to be ** Manchester's two greatest sons," to 
be the '* great twin brethren of Manchester," while all the 
lime Dalton was bom in the remote Cumberland village 
of Eftglesfield, and did not become a dweller in Manchester 
sintil the age of twenty-seven. Hence, whatever may 
be said concerning Joule* Dalton was certainly not one 
g-wbo ** aroee in the midst of a population given up to in- 
dustrial pursnits, . . and where most men's 
fcboogbts are engrossed in what shallow minds often look 
I poo as common trade avocations." We must here note 
tfith regret the political and semi-political remarks in* 
trodoced. the more gratuitously since Dalton was not a 



politician, but seems to have wisely felt that the position 
of the philosopher, as of the poet, '* should be higher than 
on the battlements of party." 

It is interesting to find that Dalton, in his pre-Man* 
Chester days — if we may coin such an expression, in addi* 
tion to meteorology, gave some attention to botany and 
entomology, and his colledions remained for tome time 
in the Keswick Museum. 

After arriving in Manchester, Dalton published an 
English grammar, which soon disappeared from circula* 
tion. But a Sheffield man re-published it some years after- 
wards as his own. 

Dalton seems to have predi^d, before the earliest ex* 
periments of Faraday in that direAion, that the gasei 
would ultimately be condensed by low temperature and 
strong pressure. 

A chapter is devoted to his remarkable optical defed of 
colour-blindness, to which he drew attention in a memoir. 
By a singular piece of bad taste, not a few Continental 
authorities thought fit to call this defed '* Daltonism." 

The investigations which led to the ** atomic theory '* 
were entered upon early in the present century. In a 
ledure delivered in January, x8co, he expressed the 
opinion that the elements are periodical and absolute :•« 
** I should apprehend," he writes, ** that there are a con- 
siderable number of what may properly be called «/#M#fi- 
tary principles which can never be metamorphosed one 
into another by any power we can control." Still he holds 
that ** we ought to avail ourselves of every means to re- 
duce the number of bodies or principles of this appearance 
as much as possible." 

An account is given of the reception of the atomic 
theory by other chemists and of the attitude of Dalton 
towards the theories of others, such as Oay-Lussac and 
Avogadro. This attitude was generally onfavourable. 
He would not admit that there are the same number of 
particles of a gas in a given volume and under a given 
pressure. 

The remaining chapters contain much intereiting 
matter. We learn that, being once unwell, ** hit doAor 
ordered a dose of James' powder. Next day the patient 
was better, and the dodor attributed the result to his pre- 
scription. * I do not well see how that can be,* said 
Dalton, * for I kept the powder until I could have an 
opportunity of analysing it.*" Though not a total 
abstainer, he seems to have come praAically to the same 
opinion as yon Helmholtz, who found that the slightest 
quantity of alcohol drove away any chance of his ** arriv- 
ing at any new and good scientific idea." 

It is recorded that he was the first to introduce the pro- 
cess of volumetric analysis. He became a Fellow of the 
Royal Society in 1822, and received the first Royal Medal 
in 1826. It almost sets one's teeth on edge to learn that 
when Dalton was presented at Court, King William the 
Fourth could think of nothing more appropriate to say 
than : — ** Well, Dr. Dalton, how are you getting on at 
Manchester— all quiet, I suppose ? " 

Notwithstanding the existence of other memoirs of * 
Dalton, this little work deserves warm recommendation. 



A Tnatisi on Practical Ckimiitry and Qualitativi Analy* 
sis. Adapted for Use in the Laboratories of Colleges 
and Schools. By Frank Clowbs, D.Sc, Professor of 
Chemistry at the University College, Nottingham; 
Member of the Councils of the Institute of Chemistry 
and of the Society of Chemical Indust^ ; Fellow of 
the Chemical Societies of London and Berlin. Sixth 
Edition. Crown 8vo., pp. 469. London : J. and A. 
Chnrchill. 1895. 
This work holds a convenient intermediate position be- 
tween the bald epitomes which are now so common and 
the elaborate woiks of Fresenius, Rose, ftc. Having 
already passed through the ordeal of six editions, it may 
be considered as in narroony with general reqairementt. 



22 



Law of Copyright in Designs. 



r CttftMtCAL >BWI, 

» July 12, 1895. 



h has the advantages that the rarer elements are not 
tgaored, special tables being famished for their recogni- 
tion. Instrudions are given for the deteAion of organic 
acids, alkaloids, and other organic substances. The use 
of the blowpipe, the microscope, and the speAroscope is 
kept in view. The student is recommended to buy pure 
reagents, rather than to attempt their preparation, which 
will in general involve a great outlay of time. 

In nomenclature little need be said. Glucinum has, 
we believe, the claim of priority, as against beryllium, 
used by the author. '* Mercuria acid *' must, however, we 
ittbmit, be merely a compositor's error. 

The illustrations of apparatus and of laboratory ar- 
rangements are eicellent, as are also the accompanying 
remarks on manipulation. 

Theoretical explanations are very properly relegated to 
wotks on descriptive chemistry. The work, in short, 
merits almost unqualified recommendation, though we 
may regret the homage paid to the Chinese system in the 
preface. 

The Law of Copyright in Designs ; together with the 

PraAice relating to the Proceedings in the Courts and 
. in the Patent Office, and a full Appendix of Statutes, 
. Rules, and Forms, the Internationa) Convention, &c. 
■ By Lewis Edmunds. D.Sc, LL.B., F.C.S., and 

F.G.S., Barristerat-Law; assisted by T. M. Stevens, 
. B.C.L., and Marcus W. Sladb, B.A., Barristers-at- 
. Law. London: Sweet and Maxwell. Manchester: 

Meredith, Ray, and Littler. Dublin : Hodges, Figgis, 

and Co. ; and Ponsonby. Melbourne and Sydney : 

C. P. Maxwell. 1895. 8vo., pp. 291. 
Thb registration of designs is a method for securing a 
proprietary right, complementary to patents for inven- 
tions. The number of designs registered annually is here 
Stated as about 20,000. It appears that, after several 
tentative enadments, copyright for three years was 
granted to any new and original design, whether such 
design be applicable to the ornamenting of any article or 
for the shape or configuration thereof, and however it is 
produced or applied. The classes of manufadure are 
articles of metal, wood, glass, earthenware, paper- 
hangings, carpets, shawls, tissues, &c. In 1883 the pre- 
vious Ads were repealed, and the provisions of the 
Patents, Designs, and Trade-marks Ads substituted. The 
decisions under these Ads have been few, and it is ad- 
mitted that many ambiguities still remain. 

The question fs raised, What is a design ? Then arises 
the question of novelty. 

Next follows publication, which may be effeded in a 
variety of ways. We come then to the question of pro- 
l^rfetorship. There are, it seems, five classes of persons 
who may be considered proprietors : the author of the 
design ; any person who employed the author to execute 
the work for good and valuable consideratibn ; any person 
acquiring the design for such consideration ; a person 
acquiring the right to apply the design to articles ; and, 
lastly, persons on whom the design on these rights may 
devolve. 

There is an elaborate sedion on infringement and the 
remedies. 

In Part II. is given the text of the Patents, Designs, 
and Trade-mark Ads from 1883 to x888, so far as they 
relate to designs, followed by the designs rules of 1890 
and 1893, and the details of the International Convention 
for the Protedion of Industrial Properly. 

The Appendices include the Statutes concerned; the 
forms ; instrudions to persons wishing to register designs ; 
and Orders in Council applying the provisions of the 
Patents, &c., Ads, to British Possessions and Foreign 
States. 

Lastly, follows a bibliography of the literature of copy- 
right in designs. 

The book, though of less interest to the majority of our 
readers than the authors* companion volume on Patents 



for Inventions, will prove highly valuable to counsel and 
solicitors, and more especially to patent agents. 



The Prospector^s Handbook, A Guide for the Prospedor 
and Traveller in Search of Metal'bearing or other J 
Valuable Minerals. By J. W. Anderson, M.A., * 
F.R.G.S., F.I.Inst., Author of " Fiji and New Cale- 
donia." Sixth Edition, thoroughly Revised and much 
Enlarged. Fcp. 8vo., pp. 176. London : Crosby Lock- 
wood and Son. 1895. 
This handy little book ought to be the pocket-companion 
of every frontier-man and explorer of the Far South. It 
will, we believe, guard the prospedor against two opposite 
evils, viz., colleding and carrying away matter of no 
value and overlooking precious deposits. Both these 
mistakes have been very often made ; yellow micas and 
certain pyrites have been taken for gold, and, on the 
other hand, platinum, nickel, and cobalt have been tossed 
aside as worthless. The author*s advice is the more 
valuable because he is not a mere compiler, reproducing 
the work of others in different language, but a field- 
geologist, who has gained experience in New Zealand, 
New Caledonia, Mexico, and the Western States of 
America. 

A valuable feature of this little book is, that it makes a 
minimum demand upon the scientific or technical know- 
ledge of the prospedor, as well as upon his funds and 
upon his means of conveying apparatus. Processes which 
are excellent in a fixed laboratory are worthless if they 
require the use of heavy and delicate instruments. The 
use of the blowpipe is very justly recommended. But we 
would suggest that a pocket spedroscope and a good lens 
will occasionally prove useful without making an objec« 
tionable addition to the traveller's impedimenta. 

We are glad to notice that, among the substances to be 
sought for, coal and petroleum are not disregarded. 

Vanadium has been overlooked ; but it is perhaps more 
likely to occur among furnace-produds,&c., than in native 
rocks. Nor do we find any mention of potash. Our 
present commercial supply of this requisite, so necessary 
alike to the chemical manufadurer and the farmer, is 
confined to Germany. Hence we suggest that it should 
be earnestly sought for in the Dominion, Australia, and 
Africa. 

An excellent feature of the work consists in the pradical 
hints which are scattered through it, and which will often 
dired the prospedor to search in right places. 

Another useful feature is the glossary of terms used in 
different countries by miners, metallurgists, &c. 

But there is the less reason for us to enlarge on the 
striking merits of Mr. Anderson's work as it has already 
reached its sixth edition. 



Year-Book of Electro-chemistry, (*• Jahrbuch dcr Elektro 

chemie.") Reports on the Advances of the Year 1894 

The scientific part elaborated by W. Nernst, Professor 

in Ordinary at the University of G5ttingen, Diredor of 

the Institute for Physical Chemistry and Eledro- 

chemistry. The technical part elaborated by Dr. W. 

BoRCHBRS, Teacher at the Duisburg Royal School for 

Machinery and Foundnes. Vol. I. 8vo., pp. 274. 

Halle : W. Knapp. 1895. 

This work affords a useful summary of the progres! 

effeded in eledro-chemistry during the year 1894. Prof J 

W. Nernst first expounds the general scientific points 0} 

view which are now accepted. 

We find a notice of the researches of Kohlrausch anc 
Heydweiller on the condudivity of pure water. It ha 
been previously shown by the former that water becomes 
less condudive the more carefully it is purified. It ij 
now proved that finally a limit is reached, or, in othei 
words, that water has a specific condudivity. 
' In the second part of the work Dr. Borchers discussei 
the applications of eledro-chemistry. He begins wit] 



CbsmicalNbws,! 
July 12, 1895. / 



City and Guilds 0/ London InsMute. 



an accooot of the produ^ion of eleAric energy from 
chemical energy. 

Prof. Ostwald, in a brilliant discourse delivered before 
the Congress of German Ele^ro-technicists {Ziit, EUktro- 
tech, nnd Electrochtmit^ 1894, Parts 3 and 4), expressed 
himself to this effed:— ** The way in which may be solved 
the greatest of all technical questions, the produdiun of 
cheap energy, must be discovered by eledro- chemistry. 
If we have a galvanic element which furnishes diredly 
eledric energy from carbon and the oxygen of the atmo- 
shere, in a quantity fairly proportionate to the theoretical 
valne, we have a technical revolution in comparison with 
which the invention of the steam-engine must vanish. 
Only conceive what will be the aspeS of our industrial 
places in view of the incomparably convenient and flex- 
ible distribution of which ele^city is susceptible. No 
amoke, no soot, no boilers, no engines, even no fire, since 
fire will be needed only for the few processes which can- 
not be conduded eledrically.** Every chemist will hope 
that this ultimate prosped is not too fascinating to be 
realised. 

In discussing eledrolytic depositions and separations 
the author qua'.es (Ztit. Eltktrottch. und EUcirochem,, 
1894, 6 and 9, and Chtm. Zeit., 1894, Nos. 59 and 71) the 
complete worthlessness of Riidorf*s diredions concerning 
the current to be applied. The author is of opinion that 
the prolonged adion of Meidinger elements, as recom- 
mended by Riidorf, is not sufficiently constant. He 
recommends the use of illuminating currents as used for 
eledro-chemical analysis in the laboratory of the High 
School at Stockholm. Few laboratories possess the 
motive power for dynamos, and still fewer are not deterred 
by the expense and the inconvenience of accumulators. 

Concerning Hermite*s *' so>called disinfeding and sani- 
tary processes," — treatment of sewage, — the most trust- 
worthy accounts are not favourable. 

Id the application of eledrolysis to dyeing there is no 
novelty of value to be mentioned, the patented processes 
of Skuzeck and Zelen having been long previously antici- 
pated by Goppelsroder. 

No one can doubt that we are, to say the least, on the 
threshold of surprising modifications and improvements 
which will be due to the applications of eledricity in the 
chexntcal arts. 



Cify and Guilds of London Institute for the Advancement 
of Technical Education, Report to the Governors, 
March, 1895. Gresham College, Basinghall St., B.C. 
1895. 
Most of our readers will already be acquainted with the 
general constitution of the City and Guilds of London 
Institute, and with the movement of which it is at once 
the seat and the embodiment. We have here a list of the 
Governors, including the ex-officio members of this body, 
the Presidents of the Royal and the Chemical Societies, 
of the Council of the Society of Arts, and of the Institu- 
tion of Civil Engineers. The President of the Institute 
of Chemistry is not here included. Then follow the 
representatives of the Corporation and of those Guilds 
who are taking part in the promotion of technical educa- 
tion, i^e,f the Mercers*, Grocers', Fishmongers*, Gold- 
smiths*, Merchant Taylors*, Salters*, Ironmongers*, 
Vintners', Clothworkers', Dyers*, Leather-sellers*, Pew- 
terers', Cutlers', Armourers' and Braziers', Saddlers*, 
Carpenters*, Cordwainers*, Plumbers*, Coopers*, and 
Plasterers* Companies. In these lists figure among others 
the honoured names of Mr. G. Matthey, F.R.S., Sir F. 
Abel, F.R.S., Sir J. D. Hooker, F.R.S., &c. Next follows 
the Council, comprising most of the above, and the 
£xecQtive Committee. 

The Staff of the Institute's Colleges includes, in pure 
chemistry. Prof. H. E. Armstrong, F.R.S. ; and H. A. 
Miers, M.A., as instrudor in crystallography, besides 
vssistants and a demonstrator. The Staff for applied 
Chemistry comprises Prof. Raphael Meldola, F.R.S., &c.| 
ith two demonstrators gnd a ledure assistant. 



f 



We notice certain very encouraging features* Unlike 
the majority of British schools, the Institution gives as 
its ** results," not the names of pupils who have ** passed **. 
some examination, but of former students who have 
proved, and are still proving in after life, the soupdnes^ 
of the training they have received. Among these sixteen 
former students in the chemical department receive pro* 
minent mention. Chemistry is, however, by no means a 
favourite subjed. Thus of the 186 ordinary students fo^ 
the Session 1893-94 ^^^y ^^ ^^^ studying chemistry, as 
compared with 71 engaged in engineering and 95 in 
physics. 

The total number of students attending the dayrclasses 
shows a falling-off as compared with the previous session, 
when the number was 2x3. Of the day-students, 197 in 
number, 70 had been previously educated at grammar and 
other endowed schools ; at middle class schools, 69 ; at 
private schools, 48 ; and at public elementary schools, t.^., 
board and church schools, only xo. Of the 992 evening^ 
students attending the College, 39 were engaged by 
day in the chemical industries. This number is small, 
but we must remember that these industries occupy in 
London only a relatively small number of persons. 

A glance at the sums presented and subscribed in sup- 
port of the Institution by the City Companies might be a 
wholesome lesson for some persons who are in the habit 
of telling their ignorant hearers that the Guilds expend 
their resources in riotous living, and that their funds 
ought to be confiscated for the promotion of fads. It 
appears that the total. amount contributed by these much- 
slandered bodies, and some of their leading members, has 
t>^Q ;£^453H35 X9^* 6d. Oi' this total £78,964 have been 
contributed by the Goldsmiths, ;(68,250 by the Cloth- 
workers, and j^66,55o by the Fishmongers. These figures 
do not include the sums contributed by, e,g , the Cloth- 
workers* Company, towards the technical departments of 
the Yorkshire College. We find, to our great satisfac- 
tion, that the Salters' Company have placed at thedisppsal 
of the Institute a sum of £1^0 yearly, to be applied to 
founding one or more Fellowships, to be entitled the 
Salters' Company's Research Fellowships, for the encou- 
ragement of higher research in manufaduring chemistfy» 
The first award under this scheme was made in January 
last, to Martin O. Forster, Ph.D., F.C.S. Dr. Forster 
had been a chemical student at the Finsbury Technical 
College during the Sessions 1888—91, and has subse* 
quentiy graduated at the University pf Wiirzjurg. 

Mr. F. H. Carr is now a Salters' Company *s Research 
Fellow, in the Research Laboratory of the Pharmaceuti- 
cal Society. 

But though satisfadory progress is being made, we 
must not, as a nation, forget the immense ground we have 
to recover, and the energy and means which we hava 
wasted over the cram and the examinational systems. 

How much good might be effeded if the friends of sci- 
entific instrudion had at their disposal the large sums 
which are still being squandered by the various *' anti ** 
movements, and in the promotion of valueless fads. The 
City and Guilds of London Institute is, we are happy to 
say, not a cramming school. 



CORRESPONDENCE. 



MYSTERIOUS DISAPPEARANCE OF PECTOSE. 

To the Editor of the Chemical News, 
Sir, — Would some of your readers kindly inform me why 
have pedose, pedosic acid, and all the other pedose 
bodies, disappeared from all modern works on organic 
chemistry, except the last edition of ** Watts' Didionary 
of Chemistry " ? Had they ever any existence except in 
text-books, or were they mere mixtures of gums and 
sugars ?— I am, &c., 

Cahbo-Hydratb. 



44 



Chemical Notices from Foreign Sources. 



t Chbuical News, 
1 ulyi2. 1895. 



USE OF MINERAL OIL FOR EXCLUDING 
AIR IN PAVY TITRATIONS. 

To the Editor of the Chemtcal News. 

Sir,— In my letter on the above subjea (Chemical News, 

Ixxii., p. II) there is an erratum of a rather important 

nature. Instead of saying that " at the time when the 

abstrad appeared I was not aware of the existence of 

Professor Brauncr," what I aAually wrote was that •* I 

was not aware of the residence of Professor Brauner.**— 

I am. &c., ^ TT A 

Alfred H. Allen. 

ShefiBeld, July 6, X895. 

BRAZILIAN MONAZITE. 

To the Editor of the Chemical News, 
Sir,— My attention has just been called to an article in 
the Chemical News (vol. Ixxi., p. 181) entitled •• North 
Carolina Monazite." by H. B. C. Nitze. In it he remarks 
that monazite is found in paying quantities in Brazil. 

May I venture to ask that gentleman, through your 
columns, ifjie knows in which State of Brazil that mine- 
ral is founo? If so, would he have any objedion to 
furnishing me with the information ? — I am, &c., 

J. Macdonald Kyle. 
The Laboratory. 
Usina Wigg, Miquel Burnier, 
Minas Geraea, Brazil, J aae xa, 1895* 



CHEMICAL 



NOTICES FROM 
SOURCES 



FOREIGN 



NoTB.— All degrees of temperature are Centigrade unleBt otherwise 
expressed. 

Zeitschrift fur Analytische Chemie. 
Vol. xxxiil., Part 5. 

Crystalline Hard Combinations in Cementation 
Steel, and in Alloys of Iron with Chromium, Tung- 
Bten, and Manganese.— H. Behrens and A. R. von 
twinge. — This article commences with an account of the 
microscopic examination of the metals in question, viz., 
of crude cement steel, obtained from puddled Dannemara 
iron; of ferro-tungsten and tungsten- steel ; of ferro- 
chrome, chrome-steel. Then follows an account of the 
analysis of the metals, qualitative and quantitative. 

Sensitiveness of some Zone Rea^ions, and their 
Application in the Recognition of Acids.— Hcin. 
Trey. — If the more frequently occurring inorganic acids, 
including oxalic acid, are grouped in such whose silver 
compounds are precipitated from acid solutions, such as 
hydrochloric, hydrobromic, and hydriodic acid, iodic 
acid, hydrocyanic, hydroferrocyanic, ferricyanic, sulpho- 
cyanic, and hydrosulphuric acid ; and, further, in such 
whose silver salts are only deposited in neutral solutioiis, 
such as phosphoric, arsenic, arsenious, chromic, oxalic, 
boric, sulphurous, thiosulphuric, and silicic acids. If we. 
secondly, divide the acids precipitable by barium, or cal- 
cium chloride again into such whose barium salts are pie- 
cipitated from hydiochloric solutions, i.e., sulphuric and 
selenic, and hydrofluosilicic acid ; and into such whose 
barium or calcium salts are sparingly soluble in acetic 
acid, i.e., oxalic, chromic, and hydrofluoric, their detec- 
tion may be more easily and simply efleaed as follows : — 
If the alkaline solution obtained by boiling in sodium 
carbonate, the original substance— supposed to be soluble 
in water or other acids — and if silver nitrate is then 
added in excess, the first mentioned silver compounds of 
the acids insoluble in nitric acids are precipitated. If we 
then filter, and add to the filtrate ammonia in such a 
manner as to superstratify the solution, so that the am- 



monia, which is specifically lighter, remains floating in 
the upper part of the test-tube, there appears at the 
surface of contaA of the two liquids a neutral zone, in 
which place, in presence of the above-mentioned silver 
salts of the acids precipitable only in a neutral solutioui 
either as a precipitate or as a slight turbidity. If, in the 
same manner, we add to another part of the alkaline 
solution hydrochloric acid until the readion is acid, and 
then barium chloride, the precipitate formed shows the 
presence of the above-named acids, which precipitate as 
barium salts from a hydrochloric solution. If we now 
add to the filtrate calcium chloride, in order to obtain 
any oxalic acid or hydrofluoric acid as calcium salts, 
which are much less soluble than their barium com- 

f>ounds, and if we convert the solution into an acetic 
iquid by the addition of sodmm acetate, we obtain the 
precipitates of the barium or calcium compounds of the 
above-named acids, i.#., barium chromate, calcium oxa« 
late, and barium or calcium fluoride. If we set aside 
those of the acids previously enumerated which have 
already been detected in searching for the bases, or in 
dissolving or acidifying the original substance, such as 
sulphurous acid, thiosulphuric acid, iodic acid, and hy- 
drogen sulphide, the presence of which, moreover, is not 
possible in an acid solution ; if we boil, after the addition 
of nitric or hydrochloric acid, the proposed method for 
deteaing the groups of acid in question may be given 
thus:— 

Acids Precipitable by Silver Nitrate, 
From nitric solution. From neutral solution. 

Hydrochloric acid. Phosphoric acid. 

Hydrobromic acid. Arsenic acid. 

Hydriodic acid. Arsenious acid. 

Hydrocyanic acid. Chromic acid. 

Hydroferrocyanic acid. Oxalic acid. 

Hydroferricyanic acid. Silicic acid. 

Hydrosulphocyanic acid. Boric acid. 

Acids Precipitated by Barium Chloride, 
From a hydrochloric solution. 
Sulphuric acid. 
Selenic acid. 
Hydrosilicofluori% acid. 

Acids Precipitated by Barium and Calcium Chloride, 
From an acetic solution. 
Chromic acid. 
Oxalic acid. 
Hydrofluoric acid. 

If the liquid is boiled after the addition of nitric acid 
(boiling is to be recommended after the addition of silver 
nitrate, in order to obtain a clear filtrate more easily and 
quickly), the solution must be allowed to cool before add- 
ing the ammonia, as on superstratifying the hot filtrate 
with ammonia at the ordinary temperature the lower cur* 
rent will stream into the upper, and thus render the 
superbtratify an illusion. This method is satisfadory and 
easy, only the students are supplied with binormal solu- 
tions ; that is, such as contain per litre double the equiva- 
lent-expressed in grms. — of acid alkali, or salt. 

Detedtion of Iodine in Urine.— Dr. A. Jolles.^-Tbe 
author has obtained satisfadory results by the two fol- 
lowing methods indicated by Sandland (Archiv der 
Pharmacie) :— i. Precipitating with silver nitrate the speci* 
mens acidulated with silver nitrate, reducing the pre- 
cipitate with zinc and hydrochloric acid, distilling the. 
solution obtained with ferric chloride, receiving the dis-^ 
tillate in solution of potassium iodide, and titrating with 
centi-sodium thiosulphate solution. 2. Evaporating the 
urine in a platinum capsule on the water-bath after the^ 
addition of sodium carbonate, charring and incinerating ^ 
the residue, slightly acidulating the aqueous solution ] 
with dilute hydrochloric acid, and distilling with ferric | 
chloride. 

On OiU.— G. de Negri and G. Fabris (translated from^ 
the original Italian by Dr. Holde). 



CRBinCAL Niwt. \ 



Helium. 



2^ 



THE CHEMICAL NEWS. 



Vol. LXXII., No. x86o. 



HELIUM. 
By WILUAM HUGGINS, P.R.S. 

Wrra Um advaotace of a bluer skv than I had during 
mf fbrmer obttrvations, I saw the fainter component of 
Ds to-day. In the chromosphere, close to the limb, both 
liMS arensnally expanded, so that the interval between 
them is very small, and on that account less easy to see. 
At a little distaoce from the limb, and especially in snit- 
abla piominences, the lines become thin, when the fainter 
component it easily overpowered if there is much 
scattered light from haae or thin cloud. D3 was seen 
doable both near the limb and in a prominence. 

I hear that Professor Hale has already seen the solar 
line doable in the United States. 

90, Upper tnlM Hill, S.W., 
Joly 10, iBgs. 



THE ANALYTICAL CHARACTERS 

OP A MIXTURE OF SALTS OF BARIUM, 

STRONTIUM, AND CALCIUM. 

By H. BAUBIGMY. 

In the determination of the elements present in a saline 
•olatioo, the deteAion of the three alkaline earthy metals, 
barimn, strontium, and calcium, is often regarded as 
delicate. The fad is due merely to the defeaive charac- 
ter of the methods employed, or to a want of precision 
in tba procedures indicated. 

Let as suppose that all the metals precipitable by am- 
noninm sulphide are eliminated, operating in presence of 
•al-ammoniac to favour their separation. In the liquid 
we transform, as usual, the three alkaline earthy metals 
into insoluble carbonates by means of ammonium car- 
bonate. We filter and wash with a dilute hot solution of 
ammoniam chloride. The filtrate will then contain 
merely the alkaline metals, and magnesium if present. 

The mixture of the three insoluble carbonates is re- 
dissolved with hydrochloric acid, which is added slowlv 
and drop by drop, so as to have a liquid which is neutral, 
or approaimately so. A small excess of acid may be 
correaed, if needful, by the addition of a proportionate 
qoantity of an alkaline aceute. Under these conditions 
potaatiom dichromate precipitates merely the barium, 
and indeed all the barium, the chromate of which is in- 
soloble in free chromic acid or in very dilate acetic acid. 
We cannot, in a neutral medium, operate with the yellow 
alkaline chromate, which precipitates equally the salts of 
•irontiom, and even those of calcium if concentrated. 

We then recognise the strontium by adding to the fil- 
trate a solution of potassium sulphate containing 2*5 
grmt. of the salt per litre, and in the sole case of the 
pretence of strontium there is a precipitate after agitating 
lor a few seconds. 

The concentration of the solution o( alkaline sulphate 

' ta Boch, in faa, that the calcium sulphate which might be 

lonned is in presence of a quantity of water more than 

.saflicient to keep it in solution. If there is only calcium 

/present there is the less trouble ; moreover, the use of the 

J alkaline sulphate, substituted for that of calcium lul- 

? phate, has the advantage of permitting the search for 

1 calciam in the same liquid. The strontium sulphate thus 

I' ( obtained has always a yellowish cast, due to a little 

V ' stftMitiam chromate carried down, in spite of the solu- 

iM bilicy of tbia latter salt in the conditions of the process. 



To detea the calcium it is necessary to eliminate the 
chromic acid, as it would vitiate all the remaining opera- 
tions. To this end, in the filtrate fi'om the strontium 
sulphate we precipitate in heat the calcium and the resi- 
due of the strontium by means of potassium carbonate ; 
we re-dissolve the carbonate, little by little, with hydro- 
chloric acid, correaing the excess of acid, if requisite, 
with ammonium acetate. To the solation we add a large 
excess of sal-ammoniac, either in crystals or In a concen- 
trated solution, and a few drops of potassium ferro- 
cyanide. 

There is formed at first a turbidity, then a precipitate, 
which increases rapidly, and which, according to Rose, is 
a double compound of potassium and calcium ferrc- 
cyanide, sparingly soluble in water, and insoluble in 
ammonium chloride. The sensitiveness is such that a 
solution of calcium sulphate, with the addition of three 
to four times its volume of water saturated with sal- 
ammoniac, is rendered strongly turbid, and precipitated 
after bein^ stirred up for a minute with a little potassium 
ferrocyanide. 

The salts of strontium produce nothing similar even in 
a highly concentrated solution ; the liquid remains per- 
feaiy clear. Still we cannot think of employing this 
method for the separation of the two metals, since stron- 
tium is always carried down, and even if the calcium is 
in decided excess the totality of the strontium is found in 
the precipitate. 

Barium gives with ferrocyanide the same reaaion as 
calcium, althovgh the sensitiveness is much less even 
with the use of sal-ammoniac. It is therefore preferable, 
for greater accuracy, to separate firstly the barium. 

These faas having been explained, it is easy to under- 
stand the necesssty of removing chromic acid after the 
separation of the barium, in order to detea calcium in 
presence of strontium. Free chromic acid oxidises ferro- 
cyanide to the state of ferricyanide, and finally there 
remains merely neutral alkaline chromate, which occa- 
sions the formation of insoluble strontium chromate, 
whilst at the same time there Is produced double potassiiim 
and calcium ferrocyanide by the slightest excess of ferro- 
cyanide, the ferricyanide having no aaion, and thus every 
conclusion is wanting in the desirable accuracy. 

In the case where the existence of calcium is the only 
question of interest, we heat at first with a concentrated 
solution of alkaline sulphate ; the filtrate then contains 
sufficient calcium to permit of its deteaion by ferro- 
cyanide. 

This remark leads to a variation in the method indi- 
cated for the deteaion of the three alkaline earthy metals. 
After having recognised barium by potassium bichromate, 
and then strontium in the filtrate by the standard solution 
of potassium sulphate (2*5 grms. per litre), we precipitate 
the rest of the strontium with a concentrated solution of 
the same sulphate, filter, saturate the liquid with ammo- 
nium chloride, and add ferrocyanide in excess to destroy 
the free chromic acid. As strontium then no longer exists 
it cannot form a chromate, and conseouently if there is a 
precipitate it is exclusively due to calcium by the aaion 
of the ferrocyanide. 

The solubility of the carbonates of these metals in am- 
monium chloride has been an objeaion to the precipitation 
of the earthy alkaline metals bv ammoniam carbonate 
in presence of a large excess of sal-ammoniac. If this 
faa is important in a quantitative respea, there is no 
reason to exaggerate this importance in ordinary qualita- 
tive determinations. In faa, a solution of calcium 
chloride at x part in 1000, and containing 50 per cent of 
the sal-ammoniac which it can dissolve— that is to say, 
half saturated—certainly gives only a scarcely percep- 
tible turbidity with ammonium carbonate ; but if we add 
ammonia to destroy the bicarbonate which always exists, 
and apply heat, there is produced a very appreciable 
aaion. It is the same with barium and strontium. 

Even when reduced to these slight proportions the 
qualitative analysis is not always defeaive. Still exp^ 



.38 



Volumetric Estimation of Phosphoric Acid. 



{ 



SliSMieAL NbWSi 

July 19. 1895. 



rience has taught me that in these limits it is advanta- 
geous to modify the process a little. Let us suppose 
that the liauor charged with sal-ammoniac contains 
quantities of barium, strontium, and calcium, only in the 
proportions of thousandths of the weight of that of the 
solvent. Under such conditions neutral chromate preci- 
pitates neither lime nor strontia. If this reagent gives 
a precipitate it is because barium is present. After 
stirring and waiting for a few moments we filter. All the 
barium having been separated, we treat with a drop of 
sulphuric acid ; if strontium is present, a precipitate of 
sulphate is quickly formed. 

Lastly, in another portion of the liquid, which must be 
saturated with ammonium chloride, we try the readion 
with potassium ferrocyanide ; a solution of barium (x part 
in xooo) giving nothing, whilst with calcium, even at a 
strength considerably inferior, we have still a very decided 
opalescence. 

Another difficulty in presence of a great excess of sal- 
ammoniac, if we have a solution very rich in magnesium, 
is, that on the addition of ammonium carbonate and am- 
monia, there may occur a separation of the double 
ammonium and magnesium carbonate. But it is very easy 
to obviate this inconvenience by diluting the liquid or re- 
dissolving the precipitate and then adding a hot and dilute 
solution of ammonium chloride, which re-dissolves the 
double carbonate. Hence I recommend the precipitate to 
be washed with hot water slightly charged with sal- 
ammoniac. Let us add, e.g., to 5 c.c. of a solution of 
ammonium chloride saturated in the cold, 3 to 5 c.c. of a 
solution of magnesium chloride (at i part in 10) ; then a 
little ammonium carbonate and ammonia ; the liquid be- 
comes turbid, and in heat the precipitate increases, 
whilst it disappears if we double the volume by the addi- 
tion of water. If we have employed only x c.c. of mag- 
nesium chloride (the proportions of the other substances 
remaining the same), the precipitate formed in the cold, 
on the contrary, disappears in part without the addition 
of water, and the liquid then remains perfedly clear. 
The proportion of magnesium has, therefore, its im- 
portance. 

In conclusion, I must point out that no method for the 
separation of strontium and calcium can be founded upon 
the simultaneous use of potassium oxalate and carbonate, 
so that the strontium would be converted into carbonate 
and the calcium into oxalate, and, after washing, sepa- 
rating by the aid of acetic acid, in which calcium oxalate 
is distindly insoluble. 

The adion in the cold varies, in fad, with the propor- 
tions of the two alkaline salts employed. For an excess 
of oxalate (3 parts to i of carbonate), we have only 
oxalates ; for an excess of carbonate (3 parts to x of 
oxalate), almost all the calcium is in the state of car- 
bonate, and the adion does not seem more distind with 
a mixture of equal parts. 

At a boiling heat, in all cases, even if there is a decided 
excess of oxalate, the adion of the alkaline carbonate 
always predominates both for calcium and strontium. — 
Bulletin Je la Soc, Chim, de Paris. 



ON AN EXPLOSION: AS A WARNING. 
By BUG. BAMBERGER. 

My assistants have since last summer prepared the crys- 
talline /-nitrodiazobenzene nitrate dozens of times, 
pressing the substance energetically on the clay plate and 
robbing it with the horn spatula without the slightest ex- 
plosive phenomenon having ever been perceptible. The 
salt is extremely less explosive than the ordinary diazo- 
benzene nitrate. Whilst a very small quantity of the 
latter detonates loudly if heated, an equally small quan- 
tity of the nitro<4erivative deflagrates only with a rela* 
tively feeble report. We have frequently rubbed up the 



salt upon porous earthen plates in quantities of 30 to 40 
grros. without any precaution. 

Unfortunately a fearful explosion has lately occurred 
which seems scarcely to be reconciled with previous ex- 
perience, and the causes of which are not explained with 
certaintv. F. Goose had prepared about 20 grms. of the 
salt by the diredion of my private assistant, Dr. Meimberg, 
and was gently turning the crystals over on a smooth 
earthen plate with a glased porcelain spatula, which bad 
no sharp corners or edges, when suddenly there ensued 
an explosion with a fearful noise and the most destrudive 
effed. F. Goose lost eight fingers— some entirely, and 
others partially. The sight of his left eye has suffered 
severely. He cautiously, as he had to do with a diazo- 
salt, avoided all pressure or rubbing. Since this mis- 
fortune we have repeatedly rubbed the nitrate with the 
porcelain spatula upon clay without any explosion. 

F. Goose remembers distindly that his preparation 
contained some black sandy grains, which he had chiefly, 
though not entirely, picked out, and which— as he believes 
—were derived from the snow used for refrigeration. 

Dr. Meimberg has, in fad, been able to produce an ex- 
plosion by a prolonged grinding up of the salt with 
remnants of gritty snow. It is merely remarkable that 
F. Goose should encounter this misfortune on gently and 
loosely turning it over. 

By this opportunity I should wish to give a warning 
against paranitroisodiazobeosene hydrate. This sul^ 
stance has recently exploded, although nothing of the 
sort was apprehended, as it was being laid in a pulverised 
and dried state upon a card paper for the purpose of 
weighing. There ensued merely a deflagration with a 
dull report; still it will always be advisable, when 
working with this substance, to proted the eyes.-- 
Berichte, xxviii., No. 6. 



A METHOD FOR THE VOLUMETRIC 

ESTIMATION OF THE PHOSPHORIC ACID. 

SOLUBLE IN WATER, PRESENT IN 

SUPERPHOSPHATES.* 

By W. KBLMAN and K. MEISSELS. 

On titrating a solution of phosphoric acid with some 
normal soda and methyl-orange as an indicator, the final 
readion occurs as soon as the salt NaHaP04 is formed, 
—that is, when one-third of the acid is saturated. If we 
use phenolphthalein as the indicator, the red colour ap- 
pears on the formation of the salt NaaHP04. In the 
acidimetric titration of a solution of acid calcium phos- 
phate, which has a neutral readion with methyl-orange, 
there occurs the following transposition : — 

3CaH4(P04)2+8NaOH=Ca3(P04)a+4NaaHP04+8HaO, 

when the calcium phosphate is eliminated; 8 mols. 
NaOH here, therefore, behave as equivalent to 3 mols. 
P2O5. On titrating superphosphates with the assumption 
of the above transposition, we sometimes, however, ob- 
tain differences which show that the various salts presenj 
in the superphosphates behave differently to the li 
salts, and that a calculation according to the above equi 
tion is not valid. 

This difficulty can be overcome on the basis of thi 
following consideration: — If we titrate a solution ci 
taining acid calcium phosphate, with phenolphthaleii 
as the indicator, and assume, according to the rul 
of saturation, that i mol. NaOH saturates | molj 
PaOsi we obtain on titration too high results ; bur; 
if, after obtaining the final readion with phenolphthalein 
we filter the liquid off from the precipitate, add methyl 
orange, and titrate back with acid, the results of thii 

'* Communication of the Technol. Museum of Vienna, 1894 (Zrt/l 
fur Anal, Chemie, xxxAl, p. 7^A' 



Clia«ICAL2ClWt,l 
Jaly 19* 1895. / 



Revision 0} the Atomic Weight of Strontium. 



29 



titrmtioQ will be as much too low as those of the former 
operatioD were too high. The arithmetical mean of both 
titrations will give the corred result. 

On the basis of these considerations the authors pro- 
ceed as follows :— ao grms. superphosphate are dissolved, 
ucundum arttm, to x litre, {a,) xoo c.c. of the filtrate 
are mixed with methyl-orange, and exaAly neutralised 
with some normal lye. Phenolphthalein is then added to 
the same solution, and semi-normal l3re is added until the 
change of colour and the quantity required are accurately 
noted. This titration requires great attention, since the 
precipitate during its formation interferes with the recog- 
nitioo of the final rea6ion. (fr.) Further, zoo c.c. of the 
solution of superphosphate are mixed in a 250 c.c flask 
With a sufficient excess of semi-normal lye, filled up to 
the mark, shaken up, and filtered. 100 c.c. of this filtrate 
are mixed with phenolphthalein, neutralised with semi- 
oormal acid, methyl-orange is added, and the liquid is 
exadly titrated with semi-normal acid. The number of 
cc. used must be multiplied by 2*5, in order to obtain the 
quantity representing 100 c.c. solution of superphosphate. 

The arithmetical mean of (a) and {b) multiplied by 
0*0355 gives the grms. of PzO^ in 100 c.c. of solution of 
•operphosphate >■ 2 grms. of the substance. 



SIMPLIFIED METHOD FOR DETERMINING 

PHOSPHORIC ACID BY MEANS OF 

MOLYBDENUM SOLUTIONS. 

By Dr. J. IIANAMAMN. 

As the molybdic method permits the most accurate deter- 
minatioo of phosphoric acid in phosphoric liquids, and 
serves as a check-method for all other determinations of 
phosphoric acid, but has merely the defed of a double 
precipiution and of the tedious conversion of the molyb- 
dcoam precipitate into magnesium pyrophosphate, the 
eSorts of analysts have for some time been direded to its 
simplification and its conversion into a volumetric form. 
Bat the gravimetric determination of phosphoric acid is at 
prcaeat so generally demanded that we have been com- 
pelled in case of superphosphates to adopt, in plac% of 
the molybdic method, the citrate method, which requires 
ooe precipitation only, though in ceitain phosphoric 
liquids rich in lime it gives values in excess. 

The yellow phospho-molybdic compound has hitherto 
Bd been esteemed of constant composition, because, on 
beating the phosphoric precipitates, molybdic acid in ex- 
cess is added to the subsiding precipitate, and is thrown 
down conjointly. We have either to precipitate a part of 
the molybdic acid by previous repeated boilings from a 
molybdic solution obtained on Sonnentchein*s method, 
and then e0e^ the precipitation of the phosphatic solu- 
tion in beat, with the molybdic solution overcharged with 
nitric acid,— or we mtist make use of such a molybdic so- 
lution as deposits, in the cold and after prolonged agita- 
tion of the mixed liquids, all the phosphoric acid of the 
solotioo as a molybdic precipitate of a constant compo- 
sition. 

In CsA, it is pradicable to throw down in the cold, and 
after vigorous stirring for thirty minutes at common tem- 
peratures, from a solution containing to xoo grms. 
tnolybdic -acid, x litre of 10 per cent ammonia, and 
li litres of nitric acid at 1*246 sp. gr., as also from the 
Maercker solution after the addition of ammonia. This 
ia efieded in such a manner that the precipitate, washed 
with ammonium nitrate and nitric acid and dried, and 
gently ignited, has a pure black-blue colour, a constant 
composition, and contains— in xoo parts by weight — 
4*ot8 phosphoric acid. The differences in weight of the 
precipitate at the various changes of colour from yellow 
to black are aa follows :— 



Orint. 



Orange 35*2335 

Greenish •• 35*2140 

Black, blue, greenish in the middle 35*2050 

Uniform black-blue •• 35*20x0 



Tare 



33'95go 
X'2490 



Twenty- five c.c. of the solution of sodium phosphats 
used, treated with the above-named molybdic solution in 
the manner described, gave a black-blue precipitate 
weighing x*245 J^ins., which, multiplied by 0*040x8, 
0*050 a 184x2, therefore in 500.0.* 0*10036 phosphoric 
acid ; 50 of this solution contained o'x grm. phosphoric 
acid. By this method we may examine high-class super- 
phosphates, and such as contain iron, as well as arable 
soils. 

The recent smooth dense filters of the firms Dreverhoff. 
and Schleicher and Sch&ll, permit of a very complete re- 
moval of the precipitate from the filter, and the separate 
treatment of each, the filter being well incinerated. If the 
precipitate has not the ccrreA black-blue colour after a 
slight ignition, it is moistened with a little ammonia, dried, 
and again ignited. Organic matter is destroyed by previous 
ebullition in nitric acid or chromic acid. The molybdic 
precipitate is heated in a platinum crucible, preferably on 
platinum wire-gause. The bottom of the crucible must 
not become red-hot, though the wire-gauze should display 
redness. At the same time this method of working allows 
the use of very small quantities of the average liquids. 
20 grms. superphosphate were dissolved in x litre of water, 
and xo cc. of the solution were poured into 35 cc. of the 
molybdic liquid, stirred for half an hour, and filtered 
cold ; the precipitate washed, dried, heated, and weighed. 
It weighed :— 

No. 1.-0*9182 grm. 

No. 11.-0*9180 grm. 
o*9i82X4'Ot8=3*6893276X5 = x8*446 p.c. PaO^. 
o*9t8ox 4*018 >»3'6885240X5« 18*442 „ 

After converting the molybdic precipitate into magne* 
sium pyrophosphate, and ignition according to the usual 
method of Fresenius, there were obtained :*- 

No. III.- 
0*03763 X 0*64 - 0*0368832 X 500 - x8*44i6 p.c PfOs. 

Twenty grms. of an arable soil, in which there had 
been obtained gravimetrically, according to the most 
trustworthy method, 0*140 per cent phosphoric acid, gave 
by the cold method, when treated with xo per cent cold 
nitric acid, after elimination of silica, and calculated on 
xoo c.c. of the acid solution, (0*7009x0*040x8. in which 
therefore 0*028162 PaOs x 5) in xoo grms. of fine earth 
0*14082 per cent V^Oy^Chtmiktr Zeitung^ vol. xix., 
No. 25. 



A REVISION OF THE ATOMIC WEIGHT OF 

STRONTIUM. 

First Papbr : The Analysis op STROirric Broiiidb.* 

By THEODORE WILLIAM RICHARDS. 
(Contioned from p. 20), 

PrifaraiioH ofMaUriats, 
Strontic BfOfNiif#.— Six different specimens of the salt 
were analysed, in order to establish tht presence or ab- 
sence of accidental imparities. 

In the first place, 500 grms. of the potest ttrontk 
nitrate of commerce were dissolved in 2 litres ol pure 
water, and four times in succession a cnbic centimetre of 
pare solphuric acid dilated with mach water was added 

* CooltibtttioDt from the Chemical Laboratory o( Harvard Col* 
lege. From tht Fnueduigs of Uu AauTHum Ac^dtimy, 



30 



Revision of the A tomic Weight of Strontium. 



• CRBkieAL NbW8» 

I July 19. 1895. 



to ti.e solution. Each time only a. small amount of pre- 
cipitate appeared at once, the rest appearing slowly. 
After waiting in each CAse three or four days, the clear 
liquid was decanted. No l)arium could be found even in 
the first precipitate of strontic sulphate ; but it is true that 
the spe^roscope is not a . very .satisfa^ory means for the 
detedion of barium under these circumstances. The acid 
solution of strontic nitrate, which had been thus almost 
if not quite freed from a possible trace of barium, was 
evaporated to small bulk, filtered from the precipitated 
strontic sulphate, and twice successively brought to crys- 
tallisation. Each mass of crystals was washed three 
times with alcohol upon the filter-pump, to free it from 
the moihcr-liquor, which mi^ht contain calcium or mag- 
nesium. After having been converted into pure carbonate 
by precipitation with ammonic carbonate and long-con- 
tinued washing, the strontium was combined with bro- 
mine. For this purpose hydrobromic acid remaining 
from the barium work, obtained by repeated fra^ional 
'distillation of the common acid, was used. 

The strontic bromide was evaporated in a platinum 
dish. This was slightly attacked, bromine having been 
set free by a little occluded strontic nitrate in the car- 
bonate. After evaporation to dryness the bromide was 
fused at a bright red heat in platinum. The alkaline so- 
lution of the fused cake was treated with hydric sulphide, 
'filtered, acidified with hydrobromic acid, warmed, filtered 
from the platinic sulphide, boiled to free it from sulphur- 
etted hydrogen, again filtered, and crystallised twice 
from water. The crystals were washed with alcohol, 
and the strontic bromide thus obtained is numbered I. 
below ; it was used for the three preliminary experiments, 
as well as for Analysis 13. 

The second sample of strontic bromide was prepared 
from similarly treated strontic nitrate which had been re- 
crystallised four times instead of twice. The nitrate was 
converted into oxide by ignition in a nickel crucible ; and 
the dissolved residue was filtered to get rid of a small 
amount of nickel. Ammonic sulphydrate gave no trace 
of colouration to a portion of the nitrate. Two re-crystal- 
lisations in a platinum bottle sufficed to free the strontic 
hydrate from a trace of undecom posed oxides of nitrogen, 
and the last crystals dissolved to form an absolutely clear 
solution in pure hydrobromic acid (see Proc» Atmr^Acad., 
xxviii., 17, bottom of page). The solution of strontic bro- 
mide was evaporated to crystallisation, the crystals were 
dehydrated, and the anhydrous salt was fused ; finally, 
after solution, standing, and filtration, a fresh crop of 
crystals was obtained. This sample, labelled No. II., 
was used for Analysis 14. 

Among several different methods for obtaining pure 
strontic salts, that recommended by Barthe and Falieres 
{youm. Chtm. Soc, Abs., 1892, p. 1277 ; Bull, Soc, Chim., 
[3]f vii., 104) seemed to promise well, and accordingly 
the third preparation was based upon their work. The 
so-called " pure " strontic chloride of commerce was dis- 
solved in water, treated with ammonic hydrate and a little 
carbonate, and filtered from the precipitate containing 
iron, aluminium, and so forth. To the filtrate was added 
an excess of sulphuric acid, and the precipitated strontic 
sulphate was thoroughly washed with dilute sulphuric 
acid and then with pure water, in the hope of freeing it 
from magnesium and calcium. When the wash water be- 
csune neutral to methyl-orange the precipitate was treated 
with enough ammonic carbonate solution to convert 
about half of it into carbonate, and the mixed precipitate 
was then washed with water by decantation until only a 
very small constant trace of sulphuric acid (due to strontic 
snlphate) was found in the decantate. The carbonate 
was then decomposed by pure hydrochloric acid, and the 
solution was allowed to stand in a glass flask for nine 
months over the undecomposed sulphate, with occasional 
shaking. The strontic chloride was decanted, the sulphate 
was washed once with water, and the filtered decanted 
liquid was evaporated in a platinum dish until most of 
the free hydrochloric acid had been expelled. The dis- 



solved residue was neutralised with ammonia, shaken 
with a little ammonic carbonate, and then filtered. To 
the greatly diluted filtrate was added an excess of pure 
ammonic carbonate, and the precipitate was washed nntil 
the wasli-water was free from chlorine. The strontic car- 
bonate was dissolved in nitric acid which had been twice 
distilled in platinum, and the nitrate was crystallised 
twice successively in a platinum dish. Each quantity of 
crystals was washed with small quantities of water and 
three or four additions of alcohol. The first mother- 
liquor, upon being fradionally precipitated by means of 
alcohol, showed distindt traces of calcium in the extreme 
solution ; thus Barthe and Fali^res*s method was not 
capable of freeing the substance wholly from calcitim. 
The second mother-liquor showed no trace of calcium 
upon the most careful scrutiny. 

200 grms. of the purest crystals, after having been dried 
at 130°, were dissolved in about a litre of the purest 
water and filtered into a large platinum dish, into which 
was passed first pure ammonia gas and then pure carbon 
dioxide through a platinum tube (see "Ammonic Car* 
bonate *'). The pure strontic carbonate was washed by 
decantation eight or ten times, dried on the steam-bath, 
and ignited in a double platinum crucible over m spirir- 
lamp. 

Part of this carbonate was converted into bromide by 
means of the purest hydrobromic acid (prepared from 
pure baric bromide and re-distilled many times ; see Proc. 
Atrnr, Acad., xxviii., 17), and the produA was digested 
for a long time with a considerable excess of carbonate. 
After filtration and evaporation the strontic bromide was 
fused in a platinum dish over the spirit-lamp ; the salt 
being perfe^ly clear while liquid. The translucent cake 
was dissolved, allowed to stand, filtered, faintly acidified 
with hydrobromic acid, and crystallised twice from water. 
Each time the crystals were washed with the purest 
alcohol. The resulting bromide of strontium was used 
for Analyses i, a, 3, 5, 6, 7, 12, 15, 16, 17, and 18. 

The next sample was prepared from the strontic car* 
bonate which had been digested with the strontic bromide 
iust described. It was dissolved in the purest hydro- 
bromic acid, and purified much as before, except that the 
salt was fused twice with intermediate crystaUisatioBs, 
instead of only once. This fourth preparation was used 
for Analysis 9. 

The fifth sample was made by the repeated crystallisa- 
tion of the combined mother-liquors obtained from the 
four previous preparations. It was used for Analyses 4, 
8, and 19. 

The sixth preparation of strontic bromide was made 
from the strontic sulphate remaining from the third. This 
residue was treated with enough ammonic carbonate to 
convert all but about 20 grms. of the sulphate into car- 
bonate. The washed strontic carbonate having been dis- 
solved in a slight excess of hydrochloric acid, the residual 
sulphate was allowed to remain in the solution for a week. 
After filtration, evaporation to dryness in platinum, sola- 
tion, a second filtration, treatment with a little ammonic 
hydrate and carbonate, and yet another filtration, the 
strontic chloride was converted into carbonate by means 
of purified ammonic carbonate (see *' Ammonic Car- 
bonate '*). After a very complete washing the strontic 
carbonate was dissolved in pure nitric acid in a platinnm 
dish. The nitrate was crystallised, dried at 150°, re-crys- 
tallised, washed with alcohol with the aid of the pump, 
dried, dissolved, and stirred with a little pure strontic car- 
bonate for a week. The filtrate containing pure strontic^ 
nitrate was diluted, brought to boiling in a platinum dish, 
and poured in a fine stream into a boiling solution of pare 
ammonic oxalate (see *' Ammonic Oxalate ") also con- 
tained in platinum. The strontic oxalate was washed 
with the purest water upon the filter-pump, until no am- 
monia could be deteded upon boiling the filtrate with 
sodic hydroxide. Nessler*s reagent still showed a trace 
of ammonia ; but since this could easily be expelled by 
ignition, and the precipitate was very hard to handle, the 



''■"/"'Sir* } Formation 0/ Citric A ci d by Oxidation of Cant-Sugar, 



31 



WMbtnf WM not carried further. After drying and 
powdering, the oxalate was converted into carbonate by 
ignition at a full red heat. The produA was now ground in a 
mortar with an equivalent amount of pure amnionic bromide 
(tee **Ammonic Bromide"), and the whole was gently 
ignited in a large platinum dish until no more ammonia 
was evolved. The too grms. of strontium bromide thus ob- 
tained formed a pure white translucent cake upon fusion 
in a large platinum crucible. The cake was dissolved in 
water, and the alkaline solution, after having been boiled 
for tome time, was neutralised with sulphuric acid. The 
clear filtrate from the stronttc sulphate was now evapo- 
rated to a volume of about 120 c.c, and diluted with 2O0 
C.C of the purest alcohol. The mixture was allowed to 
stand for a day, in order that the stronttc sulphate and 
any trace of baric sulphate which might remain should 
be precipitated, and then filtered. After three successive 
crystallisations from water, the substance was used for 
Analysis 10; a further crop of crystals from the purest 
motber-liquor served for Analysis 11. 

Considering the pains taken in the purification of even 
the least pure sample, it is not surprising that all of these 
aamplea gave quantitative results which proved them to 
be essentially identical. 

Si7««r.— The preparation of pure silver has been re- 
peatedly detailed. The most elaborate method described in 
the paper upon barium was used in the present case {Proc, 
Amir, Acad,, xxix., 64, 65). A few improvements were 
imrodttced, notably the purification of the sodic hydrate 
need for the redudion of the argentic chloride by means 
of a strong nlvanic current, instead of by hydrogen sul- 
phide. Little but iron was found in it, however. The 
noal crystals of eledroly tic silver were usually fused upon 
pore sugar charcoal or lime, in a reducing flame ; once, 
fc ow e t ef (for Analysis 10) the crystals contained in a lime 
boat within a stout porcelain tube were fused in a Spreneel 
vacuum by means of a Fletcher furnace. Two holes 
bored through the furnace at right angles to the flame 
entrance served to admit the tube. The heat was very 
nadoally applied, and after the silver had been melted all 
the apertures of the furnace were closed and the tube was 
allowed to cool very slowly. A wide glass tube set into 
Ibe porcelain tube on one end served as a convenient 
window for the observation of the fusion. 

Anunonic CarboHaU,^Two varieties of ammonic car- 
bonate were used for the work just described. The first 
consisted of ordinary pure " ammonic carbonate,'* which 
bad been dissolved, treated with a small amount of a pure 
strontium salt, and filtered. This treatment undoubtedly 
removed anv substance which could seriously interfere 
with the preliminary purifications for which this ammonic 
carbonate was used. For the final stages of the purifica* 
lion of the strontium preparations, ammonic carbonate 
was made by saturating the purest water in a platinum 
vessel with ammonia gas obtained by boiling the pure 
strong ammonia of commerce, and then passing into this 
saturated solution pure carbon dioxide. This latter gas 
was prepared bv the action of dilute nitric acid on marble ; 
it was purified by passing through washing flasks contain- 
ing water and a meter of glass tube packed with moist 
beads. Upon delivering the gas into a Bunsen flame, no 
traoe of calcium could be deteAed spearoscopically. 
Both gases were conduced into the solution through a 
platinum tube made for the purpose. The resulting 
AOUttonic carbonate undoubtedly contained more or less 
of the amines common in ordinary ammonia, but it 
coald not have contained a trace of non-volatile impurity 
capable of contaminating the strontic carbonate for whose 
preparation it was designed. 

Ammonic OxalaU.— This salt was made by neutralising 
pof« ammonia water with pure oxalic acid, which had 
been still further purified by manv re-crystallisations from 
Hydrochloric acid and water. The ammonic oxalate was 
,x crystallised twice in a platinum dish, the crystils being 
iboioughly washed each lime. The salt was wholly free 
from chlorine. 



Ammonic Bromide was prepared in the usual fashion 
from ammonia prepared in platinum and bromine purified 
according to Stas. The readion was naturally condoded 
in a flask of hard glass; but the crystallisation was 
carried on as usual in platinum. A slight excess of the 
pure white substance precipitated 3*97970 grms. of 
argentic bromide (fused, reduced to the vacuum standard) 
from a solution containing 2*28616 grms. of pure silver. 
From this experiment AgBr :Aga 100:57*4455. Stas 
found 57*445, hence the purity of the ammonic bromide is 
proved. 

A very simple and convenient platinum condenser was 
used for the preparation work described above. The tube, 
almost a centimetre in diameter, and perhaps twenty-five 
centimetres in length, is bent, somewhere contracted near 
one end, and surrounded with a condenser jacket. It is 
easy to draw out the neck of a round-bottomed flask to 
fit outside of the conical end, and if the jundure is not 
absolutely tight a thin film of condensed liquid soon 
makes it so. If the glass neck be prolonged somewhat 
above the point of jundure, evaporation from this film is 
very slow. Of course pure filter paper may be used to 
tighten the joint if water is to be distilled. The apparatus 
has the great advantages of cheapness and transparency 
over the ordinary platinum still. All the hydrochloric, 
hydrobromic, sulphutic, and nitric acids, water, and 
alcohol used in the imoortant stages of the work were 
distilled with the help of this contrivance. 

Platinum vessels have been used wherever it was 
possible to use them in the work detailed above, although 
the fad is not always mentioned. They were cleaned In 
the usual fashion. 

(To be contiooed.) 



NOTE ON TUB 

FORMATION OF CITRIC ACID BY THE 

OXIDATION OF CANB-SUGAR. 
By ALFRED B. SBARLB acd ARNOLD R. TANKARD. 

In the Cmbmical News (Ixxi., p. 296) Dr. T. L. Phipson 
announces the formation of citric acid by the adion of 
potassium permanganate, at 25* C, on cane-sugar in 
aqueous solution containing free sulphuric acid. We 
have carefully followed the diredions given by Dr. 
Phipson, and, like him, obtained no precipitate on adding 
calcium chloride to the cold neutralised liquid resulting 
from the treatment with permanganate, but on boiling a 
copious white precipitate was thrown down. 

The precipitate obtained by us differed from that 
described by Dr. Phipson in the fad that it consisted 
wholly of hydrated calcium sulphate. Thus, the precl« 
pitate, after washing with hot water and drjring at 100^ C, 
lost 20 per cent of water on ignition, and did not darken 
during the process. The residue was not alkaline to 
litmus, and did not effervesce with acid. It contained 
sulphate and calcium in the proportions required by the 
formula CaS04. 

When the precipitate produced by calcium chloride was 
treated with dilute sulphuric acid, and the filtered liquid 
concentrated somewhat, small but well-formed crystals 
were obtained ; but analysis and microscooical examina- 
tion showed that they also consisted entirely of hydrated 
calcium sulphate, (CaS04.2HiO). 

On treatment with boiling acetic acid the precipitate 
dissolved somewhat, but the precipitate produced by 
neutralising this solution with ammonia and boiling con* 
sisted entirely of hydrated calcium sulphate. 

In order to avoid any confusion from precipitation of 
calcium sulphate, we have also employed nitric neM 
instead of sulphuric acid for acidulating the cane-lugar 
solution. In this case we obtained no precipitate on 
addition of calcium chloride to the neutralised liquid, even 



Monazite — a Mineral containing Helium, 



_32 

on boiling, showing that no citric acid had been formed by 
the treatment with permanganate. 

We have also added potassium permanganate to a so- 
lution of sodium sulphite, acidulated with sulphuric acid, 
until the colour was no longer discharged. The clear 
liquid was neutralised by ammonia, and calcium chloride 
added. On boiling the liquid a copious white precipitate 
was thrown down, but this evidently could have contained 
no citrate. 

We are reludant to believe that so experienced a 
chemist as Dr. Phipson would mistake a precipitate of 
calcitim sulphate for one of calcium citrate, but it is evi- 
dent that the essential conditions must be described more 
precisely before other chemists can repeat Dr. Phipson's 
experiment with success. 

62, Surrey Street, Sheffield. 
July 13, 1895. 



( ClItlllCAL NtWS, 

I July 19, 1895. 



MONAZITE — A MINERAL CONTAINING 

HELIUM. 

By ALBERT THORPE. 

The following figures represent the results of a recent 
analytis of a sample of monazite from North Carolina : — 

Lanthanum oxide • •• •• 23-62 

Cerium oxide •• •• •• 25*98 

Thorium oxide zS'oi 

Phosphoric acid • • • • . • 28-43 

Tin oxide •• x-62 

Manganoas oxide •• •• 1*33 

Lime • •• •• 0*91 

99-90 

As this mineral is known to contain helium, the above 
results of a careful analysis may be of interest to the 
readers of this journal. Due to the far-reaching le- 
searches of Ramsay, it is probable that chemists may 
find coironium and the primordial ** material ** in some of 
the rarer minerals, and the ** lavas *' eje^ed from a^ive 
volcanoes. 



ON CERTAIN PHENOMENA OBSERVED IN THE 

PRECIPITATION OF ANTIMONY FROM 

SOLUTIONS OF POTASSIUM ANTIMONYL 

TARTRATE.* 

By J. H. LONG. 

I HAVE elsewhere called attention to the behaviour of 
solutions of tartar emeiic when treated with solutions of 
other salts (see Am, jfourn, Sci., Oa., 1889, and OH., 
1890), and with Mr. H. E. Sauer have determined the 
conditions of precipitation by carbonates, acetates, and 
phosphates (y. Anal, AppU Chem., March, 1891). 

When to solutions of the antimony sale sulphates, 
chlorides, nitrates, and oxalates of the alkali metals are 
added no precipitation occurs, even with elevation of tem- 
perature. With carbonates, acetates, phosphates, borates, 
thiosulphates, sulphites, tungstates, and some other com- 
pounds, clear solutions can be made at a low temperature, 
but precipitation follows at a higher point. The precipi- 
tate, in nearly all cases, consists of h;^drated antimony 
oxide, and its amount is a fun^ion of time, temperature, 
and amount of added salt. 

With mixtures of the tartrate and sodium carbonate, 
for instance, it was found that in the cold, at the end of 
twenty-four hours, amounts were precipitated as shown 
in the following table. In each test 5 grms. of the tar- 
trate were dissolved in 60 c.c. of warm water and cooled 



* Jountal of the A nuricaH Chemical Society, vol. xvii , No. 2. 



to 20°. Then different weights of pare sodium carbonate 
were dissolved in 35 c.c. of water ; these solutions were 
added to the others and the mixtures were brought up to 
100 c.c. They were allowed to stand until precipitation 
was complete, usually over night or longer. An aliquot 
part of the clear supernatant liquid was taken and the 
amount of antimony in solution determined. This was 
calculated to tartrate in the whole. 



No. of 


Ni,CO, 


KSbOC.H^O. 4H,0 


experiment. 


added. 


left in solution. 




Gnn. 


Per cent. 


X. 


0*1 


99'93 


2. 


0'3 


85*22 


3- 


0-5 


7036 


4- 


07 


5676 


5- 


0-9 


40-87 


6. 


1*2 


2917 


7. 


1-5 


i:iS 


8. 


2*0 



In another series of experiments the solations of car- 
bonate and tartrate were mixed as before at 20° and then 
brought to 100°, and maintained at this heat one hour. 
The precipitates formed immediately, and at the end of 
the hour were separated by filtration. The filtrates were 
tested for antimony remaining. The results are shown in 
the third column below. 



No. of 


N.,CO, 


KSbOC«H«Oe.iHftO 


experiment. 


added. 


left in solution. 




Grm. 


Per cent. 


9- 


0'2 


79*23 


xo. 


^'1 


4670 


XT. 


0-8 


2174 


12. 


I'X 


869 


13- 


1-5 


6-33 


14. 


2'0 


442 


15. 


3*5 


4-66 


16. 


5*o 


474 



On comparing the two tables it will be seen that at first 
the precipitation is much more rapid in hot solution than 
in cold, but that finally, with excess of carbonate, a more 
complete decomposition of the tartrate is effeded in the 
cold solution. Two equations can be given, according to 
which the reaAion may take place. The first of these is— 

2KSbOC4H406 + 2NaaC03 + 2HaO « 

= 2KNaC4H406 + SbjOs.HaO -»- 2HNaC03. 
The second is — 

2KSbOC4H406 + NaaCO, + HaO « 

2KNaC4H406 + SbaOj.HaO + COa. 

The first, probably, takes place in the cold solution, as 
no carbon dioxide escapes. The loss of carbon dioxide 
from the hot solution is less than called for by the equa- 
tion, because an excess of neutral carbonate is present 
and the solutions are not a^ually boiled. In any case the 
precipitation is incomplete, and by addition of increased 
amounts of sodium carbonate, a condition is reached in 
which a part of the oxide at first thrown down appears to 
go into solution aeain. 

Precipitation with sodium acetate takes place imper- 
fedly in the cold, but by heat a stronger reaAion follows. 
In both cases it was found that the results may be ex* 
pressed by the following equation :— 

2KSbOC4H406 + 2NaCaH30a + 2HaO « 

= 2KNaC4H406 + SbaOs.HaO -f 2HCaH30a. v 

With phosphates the experiments led to the conclusion! 
that precipitation takes place in a manner represented by \ 
this equation :— 

2KSbOC4H406 + HNaaP04 -|- 2HaO - 

« 2KNaC4H406 + SbaOj.HaO -f- H3PO4. 
With cold solutions precipitation is very slow, but by heat 
an amount of the antimony oxide corresponding to 75 per 
cent of the tartrate originally in solution is obtained. 



July 19, 1895.. 



} Phenomena observed in the Precipitation oj Antimony. 



33 



I have since inveitigated the behaviour of several other 
talu as ptecipitants, with the results which follow. 

Rioction with Sodium Bihorate, 
A very sharp reaAion takes place between solutions of 
botax and tartar emetic, which was studied ia the fol- 
lowing manner. In the first series of experiments 5 grms. 
of the tartrate were dissolved for each test in 60 c.c. oi 
irater, the solutions being brought to 20^ To these were 
added definite weights of borax dissolved in 30 to 35 c.c. 
of water at the same temperature. The mixtures were 
made up to xoo c.c. exaAly, and allowed to stand over 
night in a place with nearly constant temperature. In all 
cases a precipitate formed which was separated by filtra- 
tion. The analsrsis of the precipitate showed it to have 
the same composition as that formed by the sodium car- 
bonate; via., SbaOj.aq. On drying at a high temperature 
most of the water is lost, leaving pradically SbaOt. 

In each case the precipitate was separated by filtration, 
and the filtrate made up to 250 c.c. 25 c.c of this was 
taken and precipitated by hydrogen sulphide, after addition 
of tartaric and hydrochloric acids in small amount. The 
precipitation was finished on a hot water-bath, and the 
precipitate colleded on a Gooch filter, washed, dried at 
120° and weighed. The sulphide was calculated to tartrate 
on the supposition that all the antimony in solution was 
left in the original form (Sb » 120, O i» 16. The results 
<»btained are shown by these figures :— 

KSbOC«H.O,.iH,0 

left in soratioii. 

Percent. 

98-81 

9474 
8778 
74-98 
4684 

3'3X 

In another series of tests the solutions containing the 
borax and tartrate were made up to 250 cc. instead of to 
xoo cc. They were allowed to stand, filtered, and treated 
as before, giving these results:— 



No. of 


Bonx 


experiment. 


added. 




Gm. 


I. 


O'l 


2. 


0-2 


3. 


®*t 


4- 


©•8 


5- 


1-6 


6. 


3-2 



No. of 
experiment. 

7. 
8. 

9- 
10. 
XX. 
12. 

«3. 



Bonx 



Grm. 
O'X 
0*2 
0-4 

0-8 
x-6 
3"2 
6-4 
xr8 



KSbOC«Hf O. iH«0 

left in •oTution. 

Per cent. 

lOO'OO 

9715 
89-05 

75-29 
49-09 

6-01 

2-03 

099 



KSbOC«H.O.iH,0 
left in aoTuuoa. 



In a third set of experiments the liquid containing the 
borax and tartrate was diluted to 100 c.c in a flask, as in 
the first set. The flask was closed with a perforated rubber 
stopper having a long glass tube attached, and then heated 
in boiling Water one hour. The liquid was allowed to cool, 
was filtered, and the filtrate made up to 250 c.c. An ali- 
quot part, on analysis, gave results which are shown 
below. 

No. of Borax 

experiment. added. 

Grm. Per cent. 

X5. 0*x 99 88 

x6. 0-2 95-37 

X7. 0*4 88-81 

x8. 0-8 7478 

19- »'^ 47*03 

20. 3'2 3*96 

21. 6-4 1-76 

In these tables several things are immediately ap- 
parent. It appears that the precipitation is less perfed 
id hot solution than in cold, although for equal weights of 



borax the differences are not great. It is seen also that 
the amounts precipitated are greater in the strongest 
solutions. These effeds of temperature and concentra- 
tion are far less marked, however, with borax precipitation 
than with that by the sodium carbonate. 

With borax we have, in each case, a very regular rate 
of precipitation. By platting the weights of borax in the 
above table as abscissae, and the amounts of tartrate left 
as ordinates, we obtain a curve which is almost a straight 
line. 

It seems pradically impossible to precipitate all the 
antimony by excess of borax, although the amount left in 
solution is much less than when sodium carbonate waa 
used as the precipitant. Dired trials showed that the 
solubilitjr of the antimonous oxide in excess of borax 
solution is very slight, but is a trifle greater in the excess 
of sodium carbonate. The solubility in the Rochelle salt 
solution formed in the latter case will not account for this 
difference, as will appear below. 

In order to gain further insight into the readion I 
measured the amount of rotation of polarised light in 
a number of solutions before and after the separation of 
the precipitate of antimonous oxide. Some exceedingly 
interesting results were obtained, a few of which will be 
explained in detail. I dissolved 5 grms. of the tartrate 
in 50 c.c. of hot water and added 3 grms. of borax in 25 
c.c. of water, made tip to 90 cc, and heated half an hour 
in the water- bath. The solution was allowed to cool to 
20* and made up to 100*5 cc (on account of volume of 
precipitate), and filtered through a dry filter. The filtrate 
was polarised in a 200 m.m. tube giving 

«D - 3-596'. 

Seventy-five cc of the filtrate, after the addition of a 
little hydrochloric and tartaric acids, was precipiuted by 
hydrogen sulphide. The precipitate was colleaed. 
washed, and dried in the usual manner in the Qooch 
funnel. I found 0*119 g^ni. of the sulphide, correspond- 
ing to 0-3x2 grm. of KSbOC4H406.iH20, in the whole 
filtrate. 4 688 grms. had, therefore, been precipitated. 
From the outset it would naturally occur to one that the 
precipitation of antimonous oxide must be accompanied 
by the formation of sodium potassium tartrate, and that 
the polarisation tfft€L observed must, in part, be due to 
this as well as to the potassium antimonyl tartrate left. 
I have elsewhere given the results of very accurate tests 
in which the rotation constants of these tartrates were 
determined by the use of the large Landolt-Lippich 
polarimeter with the 400 m.m. tube {Am. Jonr. Set. and 
Arts, loc. cit.) From these it appears that the rotation 
of 0*3x2 grm, of the KSbOC4H4H406.iHaO, and 3-982 
grms. of KNaC4H406.4HaO (this latter corresponding to 
the tartar emetic decomposed) in xoo c.c. should not be 
over 2*6^ In the dired polarisation of the filtrate I 
found, as given above, 3*596'. It is evident, therefore, 
that something else must be present to modify the 
result. 

It is well known that the presence of boric acid in* 
creases the rotation of tartrates in a marked degree, and 
this can be readily accounted for here if we assume that 
the readion takes place according to the following 
equation :— 

2KSbOC4H406+NaaB407+6HaO- 

-2KNaC4H406+Sba03+4H3B03. 

On applying tests for free boric acid its presence was 
readily shown. We have here apparently a readion 
similar to those in which acetic and phosphoric acids are 
liberated from acetates and phosphates. 

In the last experiment it was shown that antimony, 
corresponding to 03x2 grm. of the potassium antimonyl 
tartrate was still in solution, or that 4-688 grms. had been 
decomposed. Tu do this according to the above equation 
would require 2 697 grms. of crystallised borax, and 
would leave in solution 3982 gims. of KNaC4H406.4HaO 
and x*75x grms. of H3BO3. An excess of 0*303 grm. of 



34 



Iniernaiional CcUalague Committee. 



f CtttmcAL Hwm% 
1 July i9t 189s. 



borax would be left in solution. To test the corredness 
of this view I prepared a solution containing in xoo c.c, 
at 20"— 

0-312 grm. of KSbOC4H406.iH20, 

3982 grms. of KNaC4H406.4HaO, 

175X grms. of HjBOa, 

0*303 grm. of NaaB407.xoHaO. 

This solution was polarised in the 200 m.m. tube, and 
gave- 

«D=3*590» 
which agrees very well with the result of the first experi- 
ment. Another solution, containing in xoo c.c, at 20*^ — 

0-X50 grm. of KSbOC4H406 JHaO, 
41 ig grms. of KNaC4H406.4H20, 
X'Sxx grms. of H3BO3, 

gave aD=3'66i°. While boric acid increases the rotation 
of tartrates and tartaric acid, I have elsewhere shown 
that borax decreases the rotation of Rochelle sah slightly. 
The equation probably represents the fads properly. 
(To be cootiaaed). 



PROCEEDINGS OF SOCIETIES. 



ROYAL SOCIETY. 

Internatmnal Catalogue Committ£B. 

The following Report was presented to the President and 
Council on July 5th ; the reoomnieotlalionB contained in 
it were approved of, and the Secretary was direded to 
send copies to the several correspondents, and to certain 
scientific papers :— 

Report, 

At the first meeting of this Committee (February 8, 
X894) the Memorial to the President and Council (July, 
X893) which led to the appointment of the Committee, 
and the Minute of Council of December 7, X893, ap- 
pointing the Committee, having been read, it was resolved 
to request the President and Council to authorise the 
Committee to enter diredly into communication with 
societies, institutions, &c., in this country and abroad, 
with reference to the preparation, by international co- 
operation, of complete subjed and authors' catalogues of 
scientific literature. 

Subsequently a draft circular letter was prepared, 
which, on February 22, X894, received the approval of the 
President and Council, who also authorised its issue. 

This letter was sent to 207 societies and institutions 
seleded from the exchange list of the Royal Society, and 
to a few others. It was also sent to the Diredors of a 
number of Observatories and of Government geological 
surveys, to the Foreign Members of the Royal Society, as 
well as to those of the following Societies:— Chemical, 
Geological, Physical, Royal Astronomical, Linnean, 
Royal Microscopical, Entomological, Zoological, Physio- 
logical, and Mineralogical, and of the Anthropological 
Institute. A special letter was addressed to the Smith- 
sonian Institution. 

More than a hundred replies to the letter have been 
received ; several of these are reports of committees 
specially appointed to consider the suggestions put for- 
ward by the Royal Society. A list of answers received 
up to December, X894, with brief excerpts from the more 
suggestive, was issued to members of the Committee 
early in this year. It should, however, be added that 
from some important institutions no answer has as yet 
been received. 

It may be said at the outset that in no single case is 
any doubt expressed as to the extreme value of the work 
contemplated, and that only two or three correspondents 
question whether it be possible to carry out such a work. 



It is a great gratification to the Committee that the 
matter has been taken up in a most cordial manner by the 
Smithsonian Institution, the Secretary of which, in his 
reply, refers to the desirability of a catalogue of the kind 
suggested as being so obvious that the work commends 
itself at once. The importance of having complete sub- 
jed catalogues, and not mere transcripu of titles, is also 
generally recognised. 

Some bodies and individuals take the matter up veif 
warmly, and ur^e that steps be taken forthwith to put the 
scheme into adion, this being especially true of the replies 
received from the United States ; others, while giving a 
general approval, dwell upon the difficulties of carrying 
out the suggestions put forward ; and others, again, ask 
for more details before committing themselves to any 
answer which may seem to entail future responsibili^t 
especially of a financial charader. 

Incidentally it may be pointed out as very noteworthy 
that over and over again reference is made to the great 
value of the Royal Society's " Catalogue of Scientific 
Papers." There is abundant evidence that considerable 
use is made of this on the Continent of Europe. And it 
is clear that a proposal to carry out a more comprehensive 
scheme initially under the diredion of the Royal Society 
of London is likely to meet with general approval owing 
to the fad that the Society is credited with having already 
carried out the most comprehensive work of the kind yet 
attempted. Indeed, the Academy of Natural Sciences of 
Philadelphia, U.S.A., dire&ly advocates the establishment 
of a central bureau under the Royal Society ; and several 
others more or less clearly imply that they would favour 
such a course. 

Over and over again, it is-s^ted that the produdion by 
international co*operation of a catalogue such as is con- 
templated is not only desirable, but pradicable. The 
Americans, who, as already stated, are the most enthusi- 
astic supporters of the scheme, especially dwell on the 
importance of early adion being taken. Prof. Bowditcb, 
of Harvard University, in particular, points out that if- the 
Royal Society of London wish to guide the enterprise, it 
ought to announce its views and put forward a compre* 
hensive scheme with the least possible delay. It may be 
added here that he also urges that in determining the scope 
of the catalogue a very wide interpretation shonTd be given 
to the word •• Science." 

No very precise information as to the best mode of 
putting the scheme into operation is to be gathered from 
the replies as a whole. 

It is generally agreed that the enterprise should be an 
international one. Many think that international financial 
support should and would be accorded to it, but no method 
of securing this is indicated ; others express the view that 
the cost may be met by subscriptions from societies, 
libraries, booksellers, and individuals, without Govern* 
ment aid ; and this is perhaps, on the whole, the prevailing 
feeling among those who have discussed the matter from 
a financial point of view. But in no case is any attempt 
made to form any exad estimate of the cost. 

A number of scientific bodies and institutions express 
themselves prepared to work in such a cause. The 
Secretary of the Smithsonian Institution suggests that, 
as the Institution receives all the serials and independent 
works published in America, a branch-office might be 
established there, and that it is not impossible that a sum 
of money might be given yearly in aid. The Royal 
Danish Academy is willing to render as much assistances 
as possible. It would charge an official of one of the 
Danish chief libraries in receipt of all Danish publications . 
with the task of editing slips, and would defray the cost! 
of this work. The Soci^tfe des Sciences of Helsingfors ) 
would furnish the Central Office with information as to I 
the scientific work done in Finland. The Kongl. Veien- 
skaps Akademie of Stockholm would organise a Committee I 
for Sweden. 1 

As regards language, there appears to be more unani. i 
mity than could have been expeded. Over and over again 



ICAI. NlWB, I 

J«ly 19* tin- f 



Manufacture of Explosives. 



35 



the opinioo is cxpretied that English should be the Un- 
gornge of the subjeA catalogne. Frequent reference it 
made lo the importance of quoting titles in the original 
langoage, although tome toggest that this should be done 
only io the case of those published in English, French, or 
German, and perhapt Italian. 

Some form of card catalogne appeart to be generally 
Caroored, especially in America, at the basis of the 
scheme; the Committee of Harvard University, whose 
reply is very full, in particular discuss this point in detail. 

In an interview with the Committee in March last, 
Prof. Agassis spoke very warmly in favour of the scheme, 
and of the support which it would meet with in the 
United States, especially from libraries. As others have 
done, he strongly urged that the co-operation of book- 
sellers and authors should be secured. Prof. Agassis also 
expressed the view that the regular issue to libraries and 
scwntific workers from the central office of cards or slips 
which would afford the material for the construdion of 
card catalogues would form an important source of in- 
come, at all events in his country. 

From various sides tt is urged that an International 
Congress should be held to discuss plans* This is advo* 
cated as a first step in a reply received from the Kdnigl. 
Gesellschaft der Wissenschaften in Qdttingen, a reply to 
which, not only as regards this point, but also in resped 
to the whole matter, the Committee attach very great 
weight, since it embodies in an official form views arrived 
at by the Academies of Vienna and Munich, and by the 
scientific societies of Leips ic and Gdttingen, who have 
considered the matter in common. Prof. Agassis strongly 
orged the calling of a Conference; and, among others 
who share this view, Dr. Oill, of the Cape Observatory, 
in his letter particularly dwells on the great value of such 
meetings as the means of securing unanimity of adion. 

Sach being the tenor of the correspondence, your 
Committee are convinced that initial steps of a definite 
aatare in furtherance of the scheme ought now to be 



They accordingly request the President and Coimcil to 
Hike measures with the view of calling together, in July 
of Best year (1896), an International Conference, at 
which representatives of the several nations engaged in 
scientific work should be invited to attend, with the view 
of discussing and settling a detailed scheme for the pro- 
duAion by international co-operation of complete authors* 
and subjeift catalogues of scientific literature. 

London will probably be found the best place in which 
to hold such a Conference. It may be desirable to sum- 
mon the representatives of the different countries through 
their respedive Governments, and it will obviously be 
necessary that a detailed scheme be prepared, to serve as 
a basis for discussion at the Conference. These and 
other points will require much consideration before any 
adion at all can be taken ; meanwhile it is desirable that 
a beginning should be made during the autumn, before 
the winter session of the Society. The Commiitee there- 
fore recommend that the President and Council should 
give the Committee (which includes the President and 
Officers) executive powers in order that they may take, in 
the name of the Society, such steps as they may think 
desirable with the view of calling together the above- 
mentioned Conference. 



Determination of Snlphnr in the Leads of Com- 
i merceand in Work-lead.— W. Hampe {CksmikirZiit), 
j ..^The author describes two methods :— (a) Combustion 
of the specimen in a current of dry chlorine, and employs 
two receivers filled with water containing hydrochloric 
acid, ib) The oxidation of the lead is effdSted by means 
of melting saltpetre, and the sulphuric acid formed is de- 
termindl. The reagents must be very carefully tested for 
sulphuric acid. Harope's results place it beyond doubt 
that copper may contain copper semi-sulphide even in 
presence of oxygen. 



NOTICES OF BOOKS. 



Ths Manufacturt of Explosives, A Theoretical and Prac- 
tical Treatise on the History, the Physical and Chemical 
Properties, and the Manufadure of Explosives. By 
Oscar Guttmann, Assoc. M. Inst. C.E., F.I.C« 
Member of the Societies of Civil Engineers and Archi- 
teds of Vienna and Budapest, Correspondent of the 
Imperial Royal Geological Institution of AustriSt ftc 
In Two Volumes, 8va Vol. I., pp. 348 ; Vol. II., pp. 
444. London : Whittaker and Co. 1895. 

Thb author of this thorough-going work makes in his 
Preface a somewhat alarming statement. The book, he 
tells us, *' is written for manufaAurers and experts alone* 
and anarchists and such like will find nothing new in it.** 
This sentence is certainlv open to the construAion that 
anarchists, dynamitards, &c., are, to say the least, fully 
e^ual to manufadurers and experu in their knowledge of 
high explosives. If this is true— and we are not in a po- 
sition to contravert it—'* pity *t is *t is true.** 

The first subjed taken up is that of new materials. 
Here it is not without interest to note that diversities of 
opinion prevail concerning the best method of prepara- 
tion, even in case of so anciently known a substance as 
charcoal. Another interesting faA is the case of a work- 
man secretly drinking about half a pint of glycerin 
every day, because the burning in the stomach gave him 
the same sensation as bran^. This fad may throw a 
light upon the unaccountable disappearance of glycerin 
sometimes complained of in print- and colour-works. 

The preparation of nitric acid for the mannfaAure of 
explosives is given in detail. The sale of this add by 
specific gravity it shown to be untrustworthy, especially 
if the scale of Baum^ is used, since '* an exaa definition 
of this hydrometric scale does not exist.** It is remarked 
that it is becoming more and more the custom to de- 
signate commercial nitric acid in a rational manner, 
namely, by the percentage of pure nitric monohydrate 
which it contains. 

The general properties of explosives are discussed in 
the second chapter. They are classified by Colonel Hess 
into low or dired explosives (ordinary gunpowder being 
the type), and high or indired explosives (the type gun- 
cotton), the highest effed of which is obtained by means 
of an intermediate agent. 

The views of Berthelot, and their criticism by Sir P. 
Abel and Nobel, are given, and in addition we have cer- 
tain fantastic methods for increasing the force of ^n- 
powder, dating back to the year 1563. Tables are given 
showing the composition of gunpowder at different times 
and in different countries. The manufacture and the pro- 
perties of prismatic and compressed powders are descnbed 
and illustrated. There are also a number of powders in 
which potassium nitrate is partially or entirely replaced 
by other nitrates, or by potassium chlorate. The number 
of powders in which some other substance is substituted 
for charcoal is wonderful, though in most cases with no 
definite advantage. 

The points to which attention is direded in the ex- 
amination of powders are external condition, solidity of 
grain, sise of grain, density as ascertained with a variety 
of densimeters, hygroscopic properties, and determiiution 
of moisture. Then follows the determination of the 
various ingredients. 

Next we have an examination of what are called the 
mechanical properties of the powder, via., the ioflamma* 
bility (it being shown, according to the experiments of 
Dr. bupr^, that there is scarcely any explosive which will 
not explode if spread in a thin layer on a wooden floor, 
and struck a glancing blow with, e.g,^ a broom -handle), 
rapidity of ignition, combustion, and produAs of com- 
bustion. 

The second volume opens with the manufadure of 
gun-coiioo, and its treatment from every point of view. 



36 



Petroleum. 



f Cbbmical Nivt, 

I Jaiy 19. 1895- 



It is followed by picric acid and the picratet. Picric acid 
re-melted seems to be the much-vaanted ''melinite** of 
the French, known in Britain as " lyddite.** Picric acid 
in contad with the metal walls of projediles seems to 
undergo changes which interfere with its stability. In its 
place sodium, potassium, and ammonium picrates have 
been proposed. A mixture of 432 parts of ammonium 
picrate with 568 parts of potassium nitrate is under ex- 
amination on behalf of the French Government. 
. Trinitro-cresol is used in France, under the name of 
cresylite, for filling shells and torpedoes, and is ignited 
by means of a gun-cotton primer. 

In Austria the ammonium salt of trinitro-cresol is used 
under the name of ** ecrasite,** and is said to be twice as 
powerful as dynamite. 

Blasting-gelatin is a solution of soluble gun cotton in 
nitroglycerin, and has the advantage o< being less suc- 
ceptible to mechanical shocks than dynamite; but its 
manufadure is not at all easy. 

Cordite, which has recently obtained political notoriety, 
is made by adding 58 parts nitroglycerin to 37 parts gun- 
cotton and 5 parts of vaselin. The accidents with this 
compound which have occurred at Waltham Abbey do not 
seem due to any defed in the composition. 
' A point which does not seem to have been made suffi- 
ciently prominent concerns the propagation of the shock 
from explosions of the higher explosives. This takes 
place not merely through the air, but through the earth. 
Thus, at the gun-cotton explosion at Stowmarket, the 
windows of houses at the distance of a mile from the 
maeaxine, and looking in the opposite diredion, were seen 
falhng out of their frames be/on the noise of the explo- 
sion had reached the spot. Hence belts of trees, tra- 
verses of earth, &c., are no complete protedion against 
the eStStM of explosions. 

This work commends itself most strongly to all manu- 
fadurers and users of explosives, and not less to experts, 
\rho may be called on to examine the causes and results 
of disasters of the kind in question. 



Petroltum : Us Divelopmnit and Uses. By R. Nblson 

Boyd, Member of the Institution of Civil Engineers. 

Whittaker and Co. 1895. Crown 8vo., pp. 85. 
IVe have here a most useful manual of the origin, com- 
position, properties, and uses of mineral oils. On many 
of these points consumers and dealers are lamentably 
ignorant — an ignorance greatly to be regretted concerning 
an article so valuable, if rightly used, so perilous in care- 
less hands, and introduced into trade in such enormous 
quantities. We learn here that the imports of " petro- 
leum oils *' into the United Kingdom in 1893 reached a 
total of X55,i26,667 gallons, whilst in addition 20,000,000 
gallons of oils are obtained from the shales of Scotland. 

The number of accidents due to petroleum lamps badly 
construded or foolishly managed is very serious, and if 
we consider that as much as 4,000,000 gallons have been 
stored at one time at a single wharf in London there is 
always a possibility of a conflagration on a gigantic scale. 
Concerning its storage and safe-keeping British law is 
singularly lax. There is no regulation as regards the 
quantities which may be stored at or near one place ; 
nor, apparently, as to the construdion and security of 
the magazines. It is indeed enaded that the oil kept for 
sale must have a flashing-point of 73^ F. close test. It is 
generally admitted by pradical men that this point is too 
low for public safety. In Russia the standard fl xed is 
82^; in India, iio% on account of the high temperature 
to which the oil may be exposed. Germany ventures 
upon a lower standard than our own, t.#., 70^ If this 
'figure is really degrees Fahrenheit, and not Centigrade, 
we cannot help feeling surprised. 

A very important point to which the author invites con- 
sideration is the supply of petroleum. At present our 
imports are almost exclusively derived from the United 
States and from Russia. There is here an element of 



danger, since the consumer may suddenly find the cost 
price raised by dint of combinations. It is therefore veiy 
important that other sources should be sought for, and, if 
pradicable developed. Mr. Boyd mentions here Mexico, 
Venezuela^ and the La Plata regions. In addition, there 
is Burmah, Java, and Borneo. The use of heavy mineral 
oils and of petroleum residues for heating engines is a 
sober reality which deserves to be kept in view as a 
countercheck to the manoeuvres of the coal merchants 
and the unions of the coal miners. 

The origin of petroleum is duly discussed. The theories 
of its inorganic origin, as advocated by Professors Ber- 
thelot and Mendeleeff, are now generally laid aside in 
favour of the view of Bischoff, that all the mineral hydro- 
carbons are produced by the decomposition of organic 
matter, of vegetable origin in Pennsylvania, and of animal 
origin in Canada. It is now concluded to have been 
formed, not by destrudive distillation, but at the normal 
temperatures of the earth. 

The fad that petroleum is often accompanied by brine 
is not fully explained. The heaviest mineral oil here 
mentioned is that of Baku (sp. gr. o 954), and the lightest 
that of Pennsylvania (0*730). 

This excellent little work is furnished with appendices 
showing the percentages of theoretical heat converted 
into useful work by dimrent motors ; the flashing-points 
of mineral oils permitted in different countries ; the sug- 
gestions as to the construdion and management of petro- 
leum lamps issued by the London County Council, but 
not extending to *' benzoline ** lamps ; thermic values of 
different mineral oils; and import duties on petroleum 
in foreign countries and throughout the British Empire. 
We find that, except the home kingdoms and India, 
mineral oils are nowhere admitted free. 



Chimistry, Organic and Inorganic^ with Experiminis. By 
Charles Loudon Bloxam. Eighth Edition. Re- 
written and Revised by J. Millar Thompson, Professor 
of Chemistry, King's College, London, and Arthur G. 
Bloxam, Head of the Chemistry Department, the Gold- 
smiths' Institute, New Cross, London. London: 
J. and A. Churchill. 

The work before us, which has now reached its eighth 
edition, is an excellent specimen of what we may call the 
intermediate type of chemical treatises. It does not 
aspire to the encyclopaedic charader of such works as 
those of RoBCoe and Schorlemmer, Watts, and others, 
but, on the other hand, it avoids the bald fragmentary 
charader of the manuals written in accordance with some 
syllabus. 

The subjed-matter has been modified in accordance 
with the present state of science. Argon and helium 
have been duly noticed, as far as their properties are 
already determined. Hydrazine and its derivatives are 
considered on p. 16. The periodic classification of the 
elements is expounded ; so, likewise, are the fundamental 
principles of thermo-chemistry, the static method of 
measuring chemical energy, mass adion, the kinetic 
theory of gases, and dissociation. Such matter, the theo- 
retical asped of the science, has been placed after the 
consideration of the non-metallic elements. 

After each group of metals there follows a general re* 
view of its constituents. , 

In organic chemistry, the usual division of the sub-^ 
stances discussed into fatty and aromatic derivatives has^ 
not been retained. 

Under the physical properties of organic compounds | 
we find mention of the absorption*spedra, which are 
thus mentioned detached from the general view of spec* 
trum analysis on p. 303. 

The respedive applications of chemistry, inorganic and 
organic, are very fairly explained as far as the bulk of the 
work can allow. 

The rare earths are not ignored, as is too frequently 



^^TS^S^^y GhmiciU Notices from Foreign Sources. 



e, though the elementary ch trader of some of them 
it not regarded at fully etttblithed. 

A few overtightt caonot etcape notice. Thus, in 
tpeaking of the Stephenson and Davy safety-lamps— 
recognitcd tt not tbsolulely tnistworthy^t is mentioned 
that a Davy lamp mav show as little as 0*25 per cent of 
fife-damp, whilst on the next page (p. 109) we find it ob- 
tcrved that ** the Davy lamp will not indicate less than a 
percent*" 

«^ The sonrcet of diamond are said to be Qolcondt, 
Borneo, and Braxil, thouffh the two former deposits are 
acarly exhausted, and all three together yield a much 
gaailer supply than does South Africa. 

Absinthe is mentioned without any due condemnation 
of iu use. 

Passing over, however, such trifling omissions, we must 

Sronounce Bloxam*s work to be deserving of the full con- 
deace of teachers and students. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

RoTX.— All degrees of teraperxtnre are Ceoticrade nnleu otberwiM 

SSpTMSad* 

Ziitschrift fur Analytitche Chimii. 
Vol. xxxiii.. Part 5. 

New Apparatus for Evolving Sulphuretted Hydro- 
l^eo.— F. W. Kiister (yonni. PrakL CA^iwiV).— This paper 
requires the accompanying cut. 

Vacuam Desiccation Apparatus.— L. Storch (B#r. 
OisUrr. G. and Zeit, Angew, CA#iMf#).— This paper cannot 
be intelligibly reproduced without the illustration. 

New Apparatus for Extraction.— H. W. Wiley.— 
yomrm. Anal, and AfpL Chimisiry. 

Truttwortby Still-heads.— Max Miiller and also 
L. L. de Koninck. 

Determination of Ammonia by Dittillation. — Fr. 
Stolba (Ckimiktr Ziitung). 

Watbiog-bottle for Qatet.— J. Habermaon {Ziit. 
AmgiW, Ckimie), 

Abtorptioa Apparatus for Determining Sulphur in 
Iron and Steel.— E. M. {Stakl und Eis4H). 

Fixed Abtorption Receiver for Permanent Ute.— 
Kenneth Mackensie {y<mrm» Anal, and AfpL ChimiUry). 
—All these papers require the accompanying illustrations 

Aatomatic Safety Clamp for the Rider of Balances. 
— O. A«*Richter (a circular issued by the author).— The 
arrangement is a claw which secures the rider and rises 
automatically if it has to be taken off or put on. 

Ute of Glycerin at a Heating Liquid in Soxblct*t 
Drying Apparatus.— Karl Seubert [Zeit, Angiw, Cktm,). 
'—The author shows that if a solution of common salt is 
wed as a heating liquid, leakages appear, even after a 
tbortose. This it a consequence of the galvanic cootad 
of the different metals which occasions decomposition of 
the sodium chloride and solution of the soldering. 
Glycerin is free from these disadvantages. The author 
uses it in a 60 per cent solution, boiling at 108—109*, 
when the escaping current of air indicates X04*. 

Safety Gat Jet.— F. Manoschek {DingUr's Polyieck. 
,' yoimtat, cdxxxiv., 43).— If the flame is extinguished from 
f any cause the flow of gas is arrested. 

New Form of Clay Triangle for supporting 
I Platinum Crucibles. — J. B. Coleman. — From the 
b yaumal of the Society of Ckemicai Induttry, 
§ Indicators tor Use in Titration with Normal Solu« 
tlont of Sulphide.- P. Williams.- From the Chemical 
. News. 



37_ 

Preparation of Zinc free from Arsenic. — II. 
Lescoeur.— From the CompUt Rmdus. 

Occurrence of Ammonia in Zinc Powder.— P. 
Robineau and G. Rollin.— This is said to be partially 
soluble, and can be recognised by treatment with hot 
water, and tested with Nessler*s reagent. In part it 
exists in combination, and can be lil^rated by boiling 
with soda-lye. A produd free from ammonia can be ob- 
tained by boiling and washing with dilute sulphuric add 
(X : zoo). The formation of ammonia ensues on the oxt* 
dation of the finest xinc powder in contaA with air. 

Occurrence of Sodium Cyanide in Potattium 
Cyanide.— T. B. Stillman. — From the jfoufnal pf 
Analytical and Applied Chemistry, 

Detection and Determination of Lead in Tartaric 
and Citric Acids.— R. Warington.— Prom the youmal 
of the Society of Chemical Industry, 

Determination of Chlorine in Commercial Iodine. 
— F. UUxer and A. Friedrich.— Ifi//. k. k, Qewerbe Museum 
and youmat^ the Society of Chemical Industry, 

Detedlion of Iodic Acid in Nitric Acid. — Loof 
{Apotheker Zeit, and Rep, Chem, Zeitung), ---To 5 c.c. of 
the officinal acid the author adds 0*1 grro. calcium and 
sodium hypophosphite. If iodic acid is present a coloura- 
tion appears in a few minutes, and can' be made more 
distinA by means of chloroform. 

Preparation of Pure Concentrated Hydrobromic 
Acid in Quantity.— B. L^ger.- From the Comptet 
Rendus, 

Volatility of Stannic Chloride.— T. M. Drown and 
G. F. Eldridge.— From the Technological Quarterly, 

Pretence of Arsenic and Antimony in Ores of the 
Upper Harx.— W. Hampe {Chemiker Zeitung),^0( 
interest chiefly to chemists and metallurgists of the Harx 
distriA. 

Attraction of Water by Iodine and Determination 
of Water in Iodine.— C. hitintckc^Chemiher Zeitung^ 

Detedtion and Determination of Alkyl combined 
with Nitrogen.- J. Herstp and H. Meyer.— The authors 
observed that the alkyl-iodine derivatives of pyridin and 
quinolin on heating were decomposed into the bases and 
the iod-alkyls, and determine the latter according to 
ZeisePs method. The decomposition is nearly quantita- 
live, and the quantity of alkyl found diffj.s from the cal* 
Qulated amount only by 0*8 per cent. 

Separation of VolatUe Patty Acids.- M, Wcohsler 
(Afofta/i*A4r//tf).— Liebig found that on the partial neutral- 
isation of a mixture of volatile acids and subsequent dis* 
tillation, the acid with the higher proportion of carbon 
passed over first into the distillate, whilst that with the 
lower proportion of carbon was left behind as a salt. 
Wechsier has examined in this manner mixtures of formic, 
acetic, propionic, butyric, isobuiyric, isovaleriaoic, and cap- 
ronic acids. With one exception (the separation of butyric 
and isovalerianic acids), the first fradion always contained 
the pure acid with the higher proportion of carbon, whilst 
the constituent of the last fradion was the acid poorer in 
carbon. 

Simultaneous Determination of Carbon and Nitro« 
gen. — Felix Klingeroann. — The author uses the process 
proposed by Frankland for the determination of nitrogen. 

Determination of Nitrogen in Organic Subttaocet. 
—A. Petit and L. Moufet. — From the Joum, de PharmacU 
and youmal of the Chemical Society, 

Determination of Nitrogen in Nitratet and in 
Admixture with Organic Nitrogen Componodi.— V. 
Schenke.— CA^miiUr Zeitung. 

Determination of Glycerin.— S. Salvatori (Sfoa. 
Sptr, Agrar, and youm, Chem, Soc, 

Atomic Weight of Palladium.— E. H. Keiser and 
Mary B. Breed {Amefican Chemital youmal), -^Tht result 
obtained was Pd • 106*246. 



38 



Ch&nUcMl Notices from Far&igH Sources. 



I Chbuical Niwi, 
1 July tg, i8<)s> 



DetermioAtion of Solubility of different Salts.— H. 
Landaa (Monats*hefU), — The author proceeds in the 
tame manner as Deszathy, and gives his results in the 
form of a table. 

Determination of Nitrogen in Organic Nitro-com- 
pounds, i.g.^ Nitro-glycerin.<— P. Rubtzoff.^y. Russ, 
Chitn, Soc, and youm, Chitn, Soc, 

Determination of the Solubility of Barium and 
Calcium Butyrate. — A. Deszathy Udonats*htJt€), — 
This paper requires the accompanying Ulustratipn show- 
ing the author's apparatus. 

AAion of Sodium upon Water.— M. Rosenfeld 
{y^umaljur Prakt. CA«iftt#).— Concerning the explosion 
which occurs under certain circumstances when sodium 
ads upon water, the author arrives at a conclusion 
antagonistic to previous conjedures. It was formerly 
supposed that peroxide was formed, and induced explo- 
sion by the development of oxygen. Proceeding on this 
view, Rosenfeld thought that large quantities of detonat- 
ing gas might be obtained by passing watery vapour over 
sodium without the occurrence of explosion. No explo* 
sion occurred ; but no trace of oxygen accompanied the 
bydrogen escaping. He considers that *' sodium, in its 
adion upon water, whether in open vessels or in those 
with a water-joint, is dissipated from the interior out- 
wards, as in the phenomenon of spitting ; the centre of 
the explosion lies in the interior of the metal, and the 
probable cause of the explosion is not the formation of 
detonating gas, but of a sodium hydride which is suddenly 
decomposed. The author deduces from hie experiment 
a new method of preparing caustic soda and hydrogen. 
Sodium is placed in an iron pan, which can be closed with 
a lid, and watery vapour is introduced. If the access of 
watery vapour is cut off when the development of hydro- 
gen ceases, we obtain solid caustic soda mixed with finely 
divided iron. Roienfeld considers that there is first 
formed a sodium>iron alloy, which is then decomposed 
with the liberation of iron. Vessels of silver are also 
attacked. 



yUST PUBLISHED^ Large CrowH 8vo., wiih Diagrams 
and Working Drawings, 71. 6^. cloth. 



THE 



PROCESS 



CYANIDE 

FOR THB 

EXTRACTION OF GOLD, 

And its Practical Application on the Witwatersrand 
Gold Fields in South Africa. 

By M. EISSLER, Mining Engineer, 
Author of ** The MeUllurgy of Gold," &c. 

** Thii book it just what wu needed to acquaint mining men with 
the sAual worlciog of a proceaa which it not only the mott popular, 
hot if, at a general role, the mott tuccettful for the extraAion of gold 
from tailing 8."— Af >ii»»g Journal, 

London : 
CROSBY LOCKWOOD ft SON, 7. Stationera' Hall Court. B.C. 



OWENS COLLEGE, VICTORIA UNI- 
VBRSITY, MANCHESTER. 

CHEMISTRY COURSE. 

Full particulars of this Course, qualifying for 
the Victoria University Dbokii8 with Hnnourt in Chemittry 
and for Higher Technical Oourtea in Inorganic and Organic Chemis- 
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The SESSION COMMENCES OCTOBER xst. 

H. W. HOLDER. M.A.. Registrar. 



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CITY AND GUILDS OF LONDON INSTITUTE. 

PBBtiDBNT-H.R.H. the PRINCE OP WALES, K.G. 
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The Courses of Instrudlion in ENGINEER- 
ING sod CHEMISTRY at the Institute's Colleges commence 
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< 



Jolya6.iVS* I 



Detection of Sutphates^ &c. 



39 



THE CHEMICAL NEWS, 



Vol. LXXII., No. i86i. 



A METHOD OP TRANSFERRING GASES TO 

VACUUM-TUBES FOR SPECTROSCOPIC 

EXAMINATION. 

By JAMBS YOUNG, A.R.C.Sm FC.S., and 
CHAALBS R. DARLING, Wh.Sc , A.R.C.S. (IrcUod). 

Wbilb engi^ in an examination of the gases evolved 
by ctrtain minerals^ we found it necessary to devise a 
BMtbod of filling vacuum-tubes, using small quantities of 
gas, to as to recover all excess. The subjoined sketch 
•howt the method adopted, and which we found to be 
more convenient than any other method we have tried. 

A three-way capillary tap has one of its arms, b, bent 
at right angles. The tube D, containing the gas to be 
admitted over mercury, and possessing a plain tap, e, is 
cooneded to b by means of a mercury joint. Both taps 
moat be perfedly vacuum-tight. The arm c is conneAed 
with the Sprengel or other pump, whilst the arm a is 
foaed to the aide-piece of the vacuum tube, which latter 






■ 



U made of snflScient lenph to allow of convenient fusion. 
After Joining to a, the side*piece is drawn out so that it 
nay m readily sealed off after filling. The operation is 
tJsea coododM as follows : — The three-way tap is turned 
BO aa to conneA A aod c, and pumping continued until as 
food a vacuum as possible is obtained. The tap b being 
cf^osed, B and c are then conneded, and the space between 
1^^ two taps pumped free of air. The tap is now turned 
^ BS to conned a and b, and the tap b turned on, so as 
adflsit a little of the gas into the vacuum tube. The 
ma A and c are again connedcd, and the excess of gas 
iDped oot and colleded over mercury at the bottom of 
! uUi-tabe, all loss being thoa avoided. This process 



is repeated two or three times to wa^h out the tube. The 
tubes may be sparked in ii/ii, so that the pumping may 
be discontinued at any desired moment, and the tube 
sealed off. 

We may mention that in a specimen of samarskite 
examined the residual gas obtained, after exploding with 
oxygen (to remove hydrogen and a hydrocarbon present), 
absorbing with potash, and removing excess of oxygen 
with alkaline pyroRallol, was found to be pure nitrogen. 
This was mixed with oxygen, and sparked for a consider- 
able time over potash. There was a steady diminution 
of volume during the sparking ; but at no period could 
any trace of helium be deteded spedroscopically. 

Whilst sparking the tubes with a strong current, with a 
fairly high vacuum, we obtained brilliant mirrors of plati- 
num deposited on the sides of the tube adjacent to the 
platinum eledrodes. This was particularly the case with 
those containing nitrogen, and when several strands of 
thin platinum wire twisted together were used as elec- 
trodes. With a single piece of thick wire as eledrode, 
only a slight blackening was obtained. With hydrogen 
and oxygen, using the same current, there was only a 
very slight deposit in all cases. In the nitrogen tubes, 
when the deposit attained a certain density, the current 
flashed across radially from the eledrodes, and after a 
time began to eat away the mirror from the edges, re- 
depositing a portion of it on the walls of the tube at the 
dark spaces. At the moment when the mirror began to 
condud, a brilliant yellowish-green fluorescence was ob- 
served in the glass, which was scarcely visible previously. 
We have also noticed the phenomenon mentioned by 
Prof. Ramsay, viz., that with the deposition of the mirrors 
in nitrogen tubes the gas appears to be carried down by 
the platinum, a verv high vacuum being in some cases 
obtamed, which refused to allow the passage of the 
current. 

Chemical Laboratory, Royal Military Academy, 
Woolwich, Jaly z6, 1893. 



THE DETECTION OF SULPHATES. SULPHITES. 

AND THIOSULPHATES, IN PRESENCE OF 

EACH OTHER* 

By R. QRBIG SMITH, B.Sc 

Thb separation of the acids has long been recognised as 
a matter of great difficulty by chemists and uncertainty 
by students, and it is with the intention of simplifvingtbe 
detedion of the commonly-occurring sulphur acids that 
the following method is given. Though it mav not be 
altogether new, the process does not appear to be com- 
pletely given in text-books on qualitative analysis. 

Preliminary testing will probably have indicated the 
presence of thiosulphate, in which case a dilute solution 
of the substances under examination must be employed, 
or a decomposition of the thiosulphuric acid into sulphur 
and sulphuric acid will speedily take place. Barium 
chloride in excess is added, together with a good quantity 
of ammonium chloride, which, like many salts of ammo- 
nium, potassium, and calcium, ads as a flocculant or 
coagulant, and facilitates the filtration of the barium sul« 
phate. Hydrochloric acid is next added, drop by drop, 
until it is evident that there is no further solution of 
barium sulphite and thiosulphate, and that only the sul- 
phate remains undissolved ; the solution is then filtered 
through a moistened double filter-paper, which should be 
free from ** pin-holes." 

The filtrate will probably be clear; but if not it should 
be returned to the filter for a second filtration. When too 
much thiosulphuric acid is present, the clear filtrate will 
visibly become clouded, or from being whitish will t)ecome 
more opaque : if this occurs the solution shotild be thrown 
out, and a fresh portion made more dilute. A solution of 
iodine is added to half of the filtrate oatil the colour is 



40 



Production of Cyanides. 



{ 



of a penntnentjrellow tinge ; a white precipitate indicates 
the pretence of a sulphite which has been oxidised by the 
iodine to sulphate. In the absence of a decided precipi- 
tate, traces of sulphite may be readily deteded by com- 
paring the treated and the untreated halves of the filtrate 
— a procedure which very often saves a good deal of time, 
at it is unnecessary to wait until a clear filtrate is obtained. 
The two halves are mixed, and if the jrellow colour dis- 
appeart more iodine is added ; the solution is filtered, and 
the filtrate divided into two halves as before. With a 
sUgbt turbidity filtration may be omitted. Bromine water 
is added to one of the halves when any thiosulpbate in 
the original solution shows itself as a white precipitate 
of barium sulphate, readily seen on comparing the two 
test-tubes. The thiosulpbate is by the iodine converted to 
tetrathionate, which is oxidised by the bromine water to 
sulphate. Hydrosulphuric acid would interfere with 
these readions, and ought to be eliminated by bubbling 
carbon dioxide through the solution until the gas escaping 
from the tube no longer darkens lead-paper. 



Dorfaam College ol Science, 

Newcastle-npon-Tyoe. 



THE PRODUCTION OF CYANIDES, 
By U. N. WARRBN, Research Analyst. 

SiNCB the establishment of the cyanide process for the 
separation of gold from itt ores, the race for the produc- 
tion of that compound, in quantity and at cheap rates, 
has been almost as keen as were the previous attempts to 
reduce the alluvial deposits, and thus place upon the 
market the aluminium of to- day. Potassium nitrate, 
KNOj. has long been experimented with in the hopes of 
replacing the oxygen equivalent by carbon, and by so 
doing produce KCN ; but the large percentage of oxygen 
which is in every case set free at once determines the 
destruAion of any cyanides thus formed, although traces 
of cyanides are alwajrs observed to be present after the 
partial reduAion of commercial nitrates by means of car- 
ix>o, owing to the secondary adion of the ammonia thus 
formed, due to the moisture present. 

Rochelle salt, mixed with a quarter of its weight of 
potassium nitrite, KNOa, and ignited, has given 5 per 
cent at the highest yield of cyanide obtainable, while 
most hydrated carbonaceous substances yield a still lower 
per ceat. Anhydrous sodium acetate, in admixture with 
a nitrite, has yielded as much as 30 per cent of alkaline 
cyanide ; whilst in a more recent experiment a mixture 
of 4 parts of wheaten flour to x part of nitrate, and the 
whole thoroughly mixed with 3 of magnesia and 
compressed into blocks, yielded, after ignition, from a 
varying percentage up to 15 per cent of cyanide. The 
produdion of tulphocyanides and the reduAion of the 
same by means of lime and carbon, have on several occa- 
sions given valuable results in accordance with the 
following equation :^ 

KCNS-fCaO+C-KCN+CaS+CO ; 
but at other times, in consequence probably of the diffi- 
culty in regulating the temperature, has resulted in the 
formation of worthless substitutes. 

On returning to the old method for the produdion of 
cyanides, by the incineration of nitrogen compounds, a 
valuable addition will be found in the use of lime or 
barium oxide; probably both the barium and calcium 
cyanides are more readily formed than alkaline cyanides ; 
and in lixiviation, in contad with the alkaline carbonates 
present, they at once form alkaline cyanides and earthy 
carbonates or ferrocyanides, as arranged for. 

Again, potassium and sodium cyanide together are much 
easier to produce than either separate, fusing at a much 
lower temperature, and contaim'ng more cyanogen, in con- 
sequence of the difiFerence in the equivalent of sodium 



CitBMICAL MSlN, 

J oIya6,i8^5. 

when compared with potassium. A mixture of eqaal 
weights of the two alkalis reads well in every reaped, and 
yields good results. 

Liverpool Research Laboritory. 
18, Albion Street, Evertoo, Liverpool. 



THE DETERMINATION OF URIC ACID, 

AND OF THE 

SO-CALLED XANTHIN-SUBSTANCES IN URINE. 
By F. HOPMBISTER. 

The precipitate obtained, according to Salkowski-Lodwig, 
on precipitating the uric acid with silver nitrate, contaioi 
more nitrogen than correspoonds to the uric acid obtain* 
able from the specimen of urine. W. Cameron hai 
utilised this behaviour for an approximate determination 
of the xanthin-substances. A process indicated by £• 
Salkowski can be applied for the same purpose. 

The silver precipitate obtained (Salkowski-Ludwig) 
from 500 or zooo c.c. of urine, after being carefully washed, 
is decomposed with hydrogen sulphide, and the filtrate it 
evaporated to dryness and extraded with sulphuric add 
at 2 or 3 per cent. The uric acid then remains almost 
entirely undissolved ; it is filtered off, washed, and 
weighed. The filtrate is rendered alkaline with ammonii, 
and again precipitated with a solution of silver. The 
precipitate obtained contains the so-called xanthine-sab* 
stances along with minimum quantities of uric acid. 
Salkowski estimates its quantity at 8 to xo per cent of the 
weight of the uric acid. 

M. Krilger and C. Wolff {ZeU. PhvsioL ChimU) have 
obtained in their experimenu decidedly higher values (u 
a mean 0*26 per cent of the weight of the uric aciA. 
Their process is founded on the precipitabilty of unc 
acid and of the xanthin-bases (Kossel and Kriiger name 
them alloxur-bases) by copper sulphate and bisulphite. 
100 c.c. of urine, free from albumen, are mixtd when 
boiling with 10 per cent of a solution of sodium bisul- 
phite, containing, in zoo cc, 50 grms. of the salt, and 
immediately afterwards with zo c.c. of a Z3 per cent so- 
lution of copper sulphate, and then again heated to ebul- 
lition ; 5 c.c. of a zo per cent solution of barium sulphate 
are then added to promote settlement. After standing 
for two hours the precipitate is brought on a filter u 
Swedish paper, completely washed with water which hat 
been previously boiled and cooled down to 50% and then 
used, along with the filter, for determining the nitrogen by 
the Kjeldahl process. The value obtained gives the ni- 
trogen of the uric acid pltis that of the xan thin- bases. 
A simultaneous determination of the uric acid by the 
Salkowski Lud wig process permits a calculation of the 
nitrogen belonging to the uric acid. The nitrogen of the 
xanthin-bases is found from the difference. 

A process for determining uric acid, given by Dentg^s, 
differs from that of Haycraft only in the manner of ti- 
trating the silver. The author uses a process depending 
on the formation of potassium silver cyanide in an amroo- 
niacal solution, using potassium iodide as indicator.— 
Zeitschrift fur Analytiscke Chemii^ xxxiii., p. 767. 

====== 1 



Atomic Weighta of Nickel and Cobalt.^Clemi 
Winkler.^The author has undertaken this re-determil 
tion in consequence of the published results of Q. Krv^ 
and F. W. Schmidt, and of H. Remmler. These re«u] 
indicate that nickel and cobalt, as known at present, 
contaminated with an unknown element, so that the ci 
nickel and cobalt are not known in a pure state, and tl 
atomic weights are not determined. Winkler gives 
atomic weight of nickel as 58*90, and that of cobalt] 
S9'^.—ZeUschn/t fur Analytiicfu ChimUt vol. xxjcil 
Part 5. 



CBBMfCAL 2CKWt» \ 

July 26, 1895. / 



Revimn of the Atomic Weight of Strontium. 



41 



LONDON WATER SUPPLY. 
Report on thb Composition and Quality of Daily 
Samples op thb Watbr Supplied to London 
POR THE Month Ending June 30TH, 1895. 

By WILLIAM CROOKES, F.R.S., 

and 

PROFESSOR DEWAR. F.R.S. 

To Major-General A. De Courcy Scott, R.E., 
Wattr Examiner, HitropoUs Water Act, 1871. 

London, July izih, 1895. 
Sir, — We submit herewith, at the request of the 
Dire^ors, the results of our analyses of the x66 samples 
of water coUeaed by us during the past month, at the 
several places and on the several days indicated, from the 
mains of the London Water Companies taking their 
supply from the Thames and Lea. 

In Table I. we have recorded the analyses in detail 
of samples, one taken daily, from June ist to June 30th 
indtisive. The purity of the water, in resped to organic 
matter, has been determined by the Oxygen and Com- 
bustion processes; and the results of our analyses by 
these methods are stated in Columns XIV. to XVXIL 

We have recorded in Table IL the tint of the several 
samples of water, as determined by the colour-meter 
described in a previous report. 

In Table IIL we have recorded the oxygen required to 
oxidise the organic matter in all the samples submitted 
to analysis. 

Of the z66 samples examined one was recorded as 
** slightly turbid,'* the remainder being clear, bright, and 
well filtered. 

June has been a very dry month. Three-hundredths of 
an inch of rain fell at Oxford on the xst, and eight-hun- 
dredths on the nth. With these trifling exceptions no 
rain fell till the 26th, when there was a downpour of ihrec- 
quarters of an inch. On the sSih nearly a quarter of an 
inch fell, followed on the 29th by two-hundredths addi- 
tional, making a toUl of 1*12 inch. The mean of 25 years 
being 2-21, the deficiency is 1*09 inch. Unfortunately 
neither the river nor the country is much the better for the 
Z'xa inches falling in June, The bulk of this coming down 
on two stormy days near together, little time was allowed 
for the water to sink into the ground. The consequences 
being, swollen water courses for a few hours, a sudden 
flood in the river followed by as rapid a subsidence, and 
little if any permanent good, as compared with what 
would have been occasioned by the same amount of rain 
distributed over a greater number of days. 

The purity of the Thames- derived waters is now at a 
very high level, and there is not much room for improve- 
ment in chemical quality ; but that it is kept up and some- 
what improved in all respeds, the following table, giving 
the comparison between the composition of the waters in 
May and June of this year, is a satisfadory proof. 

iSg$.— Averages 0/ the Five Supplies derived from the 
River Thames, 
Coomon Nitric Oxygen. Organic Organic 

Salt. Add. Hardneif. reqd. Carbon. Carbon. Colour. 
Per Per Per Per Per 

gall. gall. Degrees, gall. gall. gall. Br'n:Blue. 
Meant. Meant. Meant. Meant. Meant. Maxima. Meant. 
May 1*994 0*908 14*41 0*045 o'^^^ 0206 13*5:20 
June 1*951 0*903 13*85 0*034 o"o8x o-xoo xx*4:2o 

Comparing the composition of the waters in June with 
that of the corresponding month last year shows an almost 
equally satisfaAory result. 
Baderiological examinations of the waters from the 

Sineral wells of the Water Companies, and from the un- 
tered water of the river, have been proceeded with 
throughout the month. At the works the average number 
if microbes was 19, and in the river the average was 
7625 microbes per c.c. The amount of impurity commu- 



nicated to the river by a heavy storm following a long 
drought is shown by baderiological examinations before 
and after the heavy storm on the 26th. Before the storm 
the Thames contained 3230 microbes per c.c, and imme- 
diately after the numbers rose to 29,032. This large 
increase produced no perceptible augmentation of the 
number of baderia in the clear water wells of the 
respeAive Companies. A careful baderiological examina- 
tion of the water at the Companies' works on the days 
succeeding the storm showed that the filtration was 
effedive, no appreciable increase being deteAed in the 
number of microbes present. 

We are. Sir, 

Your obedient Servants, 

William Crookis. 
James Dbwar. 



A REVISION OF THB ATOMIC WBIQHT OP 

STRONTIUM. 

First Paper : The Analysis of Strontic Bromide.* 

By THEODORE WILLIAM RICHARDS. 
(Continaed itom p. 31). 

Method of Analysis, 
As in the case of baric bromide {Proc, Amer. Acad., 
xxviii., 23), the silver required to precipitate all the bro- 
mine in strontic bromide was determined, aw well as the 
amount of argentic bromide formed by the precipitation. 

The chief problem which presented itself was the pre- 
paration of pure dry neutral bromide of strontium for 
weighing. In preliminary analysis the salt was ignited 
or fused in a platinum crucible, and weighed as the baric 
bromide had been. The decomposition of the salt wal so 
great, however, that the uncertainty of the alkalimetric 
corre&ron sometimes amounted to two or three tenths of 
a m.grm. ; hence this method was clearly inadmissible. 

The fusion of the salt in a platinum boat in a stream of 
nitrogen gave much better results, and two or three 
further preliminary determinations by this method gave 
promise of much greater accuracy. It is probable that 
the slight decomposition which occurred even in the at- 
mosphere of nitrogen was diie to the presence at 250—300'' 
of a slight trace of moisture. 

The presence of an excess of hydrobromic acid must 
necessarily lessen or prevent this decomposition ; hence 
in three succeeding determinations (Nos. 13, 14, 15, 
below) pure dry hydrogen bromide was added to the 
nitrogen in which the combustion was conduced. 

In these cases, however, the platinum boat, which had 
previously remained quite constant in weight, was evi- 
dently attacked, since upon one occasion (Exp. 15) it lost 
over two-tenths of a m.grm., and the pure white strontic 
bromide became tinged with a brown colour. The weight 
of the boat after each fusion was taken as the true weight, 
because the bromide of platinum, if formed, must precipi- 
tate nearly as much silver as the bromide of strontium. 

In order to avoid the corrosion of the boat, hydrogen 
was added in small quantities to the mixture of gases. 
This, by preventing the dissociation of the hydrobromic 
acid, efiedlually preserved the platinum, and the boat re- 
mained constant in weight. The pure translucent or 
transparent colourlessness of the fused salt left nothing 
to be desired. A somewhat complex piece of apparatus 
was needed for the purpose. (See Fig. i). A mixture of 
six volumes of pure nitrogen (made by passing Itir and 
ammonia over red-hot copper) and one volume of pure 
hydrogen was delivered from a gas holder through a succes- 
sion of tubes of red-hot copper, dilute chromic and sulphuric 

* CoDtributioos from the Chemical Laboratory of Harvard Col- 
lege. From the Frouidingi 0/ the Amtrican Atademy. 



42 



Revision of the Atomic Weight of Strontium. 



'CBRIliCAL NlWB, 

I Jul'- 26, 1895. 



acids, concentrate*^ alkaline pyrogallol, and fused potash, 
into the arrangtit.cnt fur preparing hydrobromic acid. 
This, as well as all the apparatus following, was without 
rubber connexions, the ground joints being made tight by 
means of syrupy phosphoric acid (Mo ley) and flexible by 
means of fine glass gridirons (Finkener). The pure dry 
nitrogen and hydrogen were led in il.e first place into a 
flask containing bromine, and then over asbestos and red 
phosphorus saturated with pure fuming hydrobromic acid. 
The bromine and hydrobromic ; cid were proved to be 
pure by the usual quantitative analysis, and the red phos- 
phorus was ground and washed many times with pure 
water to free it as much as possible from chlorine (Stag). 
The mixture of pure slightly moist hydrogen bromide, 
nitrogen, and hydrogen was now dried by calcic bromide 
free from chlorine anu .odine, and thus became ready for 
use. 

The hard glass tube used for heating the platinum 
boat containing the strontic bromide was ground very 
tightly into its socket of soft glass, since it was not ad- 
visable to risk the presence of phosphoric acid here. The 
powdered nearly anhydrous strontic bromide, having been 
packed tightly into the boat and carefully pushed into 
position in the fusion tube, was thoroughly dried at 200^ 
in a stream of pure air. The elaborate apparatus for pre- 
paring the mixture of gases was now connected with the 
fusion tube, and when all the air had been expelled the 
boat was slowly heated to cherry* redness until the strontic 
bromide was wholly fused. The temperature was then 
allowed to fall a little below 600°, and the solidified bro- 
mide of strontium was freed from any possible excess of 
hydrobromic acid by a current of dry hydrogen and nitro- 
gen free from acid, delivered through a short-cut tube 
(see Fig. 1). 

The almost red-hot boat was now transferred as quickly 
at possible to the light weighing bottle, within which it 
was allowed to cool. In the preliminary work (and in 
Analyses 13 and 14) this bottle was stoppered at once and 
cooled in an ordinary desiccator. Subsequently an im- 
proved desiccator was devised for this purpose. A wide 
glass tube capable of containing the weighing-bottle was 
drawn out at one end to a fine tube, which was fitted 
with a ^ound glass stopper. The other open end was 
made slightly conical and ground into a receptacle which 
was in its turn attached to a drying tube containing fused 
potash. The accompanying sketch supplements this 
description (Fig. 2). 

While the boat was still hot within the fusion tube, the 
stopper of the weighing bottle was placed in the horizontal 
desiccator tube. The moment after the transference of 
the boat into the bottle, both together were slid into the 
momentarily opened desiccator tube by means of a glass 
rod which projeded from the receptacle. The bottle was 
held by means of a glass carriage during this manipula- 
tion. 

The open weighing bottle, with its stopper and fused 
contents, could now be heated indefinitely in a current of 
pure dry air at any temperature below the softening-point 
of soft glass. At the moment when it was desired to 
close the bottle, it was only necessary to elevate the 
desiccator tube from the horizontal to the vertical posi- 
tion, and the hot stopper fell automatically into the 





Fig. 2. 



equally hot bottle. The desiccator tube was now closed 
above, and allowed to cool at least four hours in the 
balance room. It is needless to say that before taking 
the final weighing of the bottle its stopper was loosened. 
Having thus obtained as nearly as possible the true 
weight of the typical salt of strontium, the remainder of 
the analysis was conduced in a manner essentially simi- 



lar to that adopted in the case of baric bromide {Proc. 
Amer» Acad,, xxviii., 24). Since it is unnecessary to de 
scribe again most of the precautions, nothing will bi 
noted below excepting those particulars in which the de'^ 
tails of the work differed from those already given. Twoj 
analyses, which were vitiated by known errors, are 
omitted from the tables. 



ClIBMICALflBWf,! 

Joly a6, 1895. f 



Phenomena observed in the Precipitation oj Antimony. 



43 



(Pare dry nitrogen and hydrogen enter the apparatus 
through the tuhe at the left. The arrangement for pre- 
paring this miiture is not shown. Upon closing the 
pinchcock in the upper left-hand corner, the gases are 
driven through the flasks and charged with dry hydro- 
bromic acid; upon opening the pinchcock, the hydro- 
static pressure below causes the gases to flow through the 
upper short-cut tube and efledually sweep out the acid 
from the fusion tube. This latter tube, containing the 
boat in which the strontic bromide is fused, is at the right 
of the figure). 

(To be contiooed). 



ON CERTAIN PHENOMENA OBSERVED IN THE 

PRECIPITATION OF ANTIMONY FROM 

SOLUTIONS OF POTASSIUM ANTIMONYL 

TARTRATE.^ 

By J. H. LONG. 

(Contiooed from p. 34). 

Ill the above nothing has been said about certain pecu- 
Karitiea observed in the formation of the precipitates. 
When cold dilute solutions of borax and the tartrate are 
mixed 00 reaAion takes place immediately, but with warm 
atrong solutions, a precipitate seems to form as soon as 
the two liquids are poured together. In a former paper 
(youm* Anak ApfL Cksm,, loc. cit,) I pointed out the 
important and exceedingly curious fadl that in the reac- 
tion between carbonates or acetates on the one hand, 
with the tartrate on the other, while no precipitate may 
appear immediately, perhaps not in hours, indicating a 
decomposition, the polarimeter shows that such has taken 
place. Here, also, we have evidence that a readion has 
taken place even without precipitation, and this the 
polarimeter furnishes. The matter can be best explained 
by giving the details of several experiments. 

I made five solutions by dissolving 5 grms. of the tar- 
trate as before in 55 to 60 c.c. of warm water, cooled to 
so*t and added certain weights of borax in small volumes 
of water, making the solutions finally to 100 c.c. at 2o^ 
These solutions were polarised immediately in the 200 
m.m. tube, with the following results :— 



No. of KSbOC«H«0«.iH.O Na,B«0,.ioH.O 
•JKpt. taken. added. 

s •• •• 5 grms. 0*5 grm. 

a •• .. 5 ft 1*0 „ 



2*0 grms. 
4'o w 



•0. 

1208« 

5-53^ 
4x0° 

375° 



The normal rotation of the tartrate at 20* in the 200 
m^m. tube, with a concentration of 5 grms. in xoo c.c, I 
hare shown to be- 
no - I4'i03*. 

The cfled of the borax is therefore marked, but the ex- 
tent of the decrease in rotation depends on the number of 
miaates intervening between the mixing of the solutions 
mad the completion of the observation in the polarimeter. 
A gradaal decrease in the readings was in all cases ob- 
•enred, ontil the solutions became finally too turbid for 
obeenration from the beginning precipitation. The first 
•olotiofl, for instance, in the above table was read as fol- 



io hours, 30 minutes, ao <■ 12*08* 
10 „ 45 M .» - ii-S?" 
10 „ 55 r n - "'So* 

AlUr standing some hours, the solutions deposited a pre- 
cipitate and cleared up. On again polarising I found :— 

* Jcumml oflht Amirifan Chemica' iOiirtjft %ol. xvii , No 2. 



No. 

I 
2 

3 
4 
5 



ao. 
IX*52* 

9*0 1* 
5-a9* 
3-9a** 
365^ 



These observations were made in a 200 m.m. tube, but 
similar solutions were polarised in a 400 m.m. tube with 
perfect sharpness, the readings agreeing within 0*02*, as 
IS possible with the large and excellent instrument used. 
I mention this to prove the perfeA transparency of the 
liquids, and to show that the decreased rotations observed 
at the start were not due to any loss through precipitation, 
but were in consequence of changes preceding precipita- 
tion, these changes taking place very gradually. 

We have here a phenomenon reminding one of the bi- 
rotation of solutions of certain sugars, but depending on 
a different cause undoubtedly. In the readion between 
the same tartrate and sodium carbonate the same change 
was observed, but through a longer period. A solution 
containing in 100 c.c. one-tenth grm. of the carbonate 
and 5 grms. of the tartrate gave, at the end of five minutes 
in a 400 m.m. tube, a rotation of 25*582^ after thirty 
minutes, 25*580*^ ; that is, praAically the same ; but after 
twelve hours, 24*480°. A perfedlly clear mixture can be 
made containing 5 erms. of the tartrate and nine-tenths 
grm. of sodium carbonate in xoo cc When polarised 
immediately, I found with this in the 400 m.m. tube 
ao B 11*57°; s^ter ten minutes, xx*50*; after twenty-five 
minutes, 1 1*132°; and after sixty-five minutes, xo*55°. 

In the normal readion between carbonates or boratea 
and the potassium antimonyl tartrate a precipitate should 
be formed, but we find that at a low temperature this is 
much delayed. If precipitation alone were taken ata the 
indication of a readion it would neceasarily appear that 
at the outset no readion takes place, but the behaviour 
with polarised light shows the error in this view. It 
is evident that a read ion begins immediately and pro- 
gresses far toward completion in some of the cases con- 
sidered before even the first polarisation can be made ; 
that is, within two or three minutes. This first part of 
the readion is the beginning stage of precipitation and 
may consist in the formation of some intermediate pro* 
dud, which finally decomposes. I have elsewhere shown 
{Am, Joum, Sci, and Aris, loc. ciL) that the rotation of 
potassium sodium tartrate is decreased by the addition of 
sodium, thallium, and lithium salts, but is increased by 
the addition of potassium and ammonium salts, and that 
this readion is fully accounted for if we assume the form- 
ation of sodium tartrate, sodium-thallium tartrate, or 
sodium-lithium tartrate in the one case, or of potassium 
or potassium-ammonium tartrate in the other. In the 
present instance we evidently must admit the formation 
of sodium-potassium tartrate from the instant the solu- 
tions are mixed, but that the readion is a progressive one. 
The potassium antimonyl compound with a high rotation 
gives place to the potassium-sodium compound with a 
much lower rotation. There is nothing to show, how- 
ever, in what form the antimony is held. 

Possibly the readion may be explained by assuming 
the formation of an intermediate produd according to this 
equation :— 

2KSbOC4H406+NaaB407-2KNaC4H406+(SbO)«B«07. 

If the last compound is formed it must break up in this 
manner — 

(SbO)sB407 -h 6H3O + XHaO « 4H3BO3 -k- SbtOs. XH2O, 

leaving a hydrated oxide of antimony with more water 
than the final precipitate contains. By loss of water, 
possibly, this hydrated compound must, in time, settle out 
as a precipitate. It has been explained that, by boiling, 
the precipitate forms and subsides soon. At 20°, even 
after what I have called the preliminary stage of precipi- 
tation, may have occupied hours, the adual formation of 
the precipitate may consume an equally 1 ng time. The 



u 



Phenomena observed iu the Precipitation of Antimony . 



j44 

precipitate is a growth through an invisible and a visible 
stage, and what is tme here is true of the next case to 
be given. 

Rtaction with Sodium Tuiigstati. 

Cold solutions of the tartrate give no immediate pre- 
cipitate when mixed with cpld solutions of ordinary 
sodium tungstate, but on standing the mixtures gradually 
become turbid, and finally deposit a sediment. The com- 
position of this depends largely on the temperature and 
concentration. The precipitate formed in the cold, col- 
leded, and dried at 105—110° C, consists essentially of 
antimony oxide. A precipitate formed by mixing hot so- 
lutions has praAicaliy the same composition, but if ob- 
tained after long heating it contains a relatively larger 
amount of tungstic acid. 

In a series of tests made by mixing hot solutions of 
the two salts, and allowing the mixtures to stand several 
hours to cool, the following results were obtained : — 



f Chbmical Ntws, 



KSbOC«H«Oe.}H.O 
in xoo c.c. 


SbiS. Per cent 
Na,W0«.2H,0 Weight of from ofSbia 
in 50 c.c. precipitate, same, precipiute. 


1 grm. 

2 gnns. 
4 >• 

5 H 


2 grms. 0*3087 0*3467 8022 
2 „ 0*6442 07291 8084 
2 „ 0*5728 0*6486 8o*88 
2 „ 0*7222 0*8170 80*79 



The mixtures were made in platinum dishes holding 
about 200 c.c, and as the precipitates formed as a 
coherent coating on the dishes they were easily washed, 
dried at zzo^ and weighed. They were then dissolved in 
diluted hydrochloric acid, which left a small amount of 
tongsttc acid in each case in ilocculent form. The solu- 
tions were then filtered, and, after the addition of some 
tartaric acid, were precipitated by hydrogen sulphide in 
Che usual manner. The sulphide precipitates were col- 
leded on a Gooch, dried at xio% and weighed. It will be 
seen that the results are a little low to correspond to pure 
antimony- oxide as the composition of the white precipi- 
tate. This compound contains 83*3 per rent of antimony. 
The compound SbaOs.HaO contains 78*4 per cent. The 
lower results are doubtless due to the small amounts of 
tnngstic acid left in each case on treatment with hydro- 
chloric acid, and referred to above. 

In a second series of experiments constant amounts of 
the tartrate in hot solutions were mixed with varying 
amounts of the tungstate, likewise in hot solution. The 
white precipitates which formed were colledled and 
weighed as before, with the following results, which show 
the efiedt of excess of tungstate on the amount of precipi- 
tate. In each case 2 grms. of the tartrate were taken in 
100 C.C., and the tungstate in 50 c.c. 



Tungatate taken. 


Precipitate obtained. 


0*5 grm. 


0*1070 


10 „ 


04598 


a-o grms. 


0.5762 


3*0 i> 


0*5861 


4-0 .. 


0*6143 


5*0 „ 


0*6185 



From this, it is plain that the amount of precipitate is 
not mnch increased by great excess of the tungstate be- 
yond a certain point. In the cold, precipitation is much 
less perfed, while, by boiling, fully three-fourths of the 
theoretical yield of oxide from the tartrate can be ob- 
tained. 

By working with cold solutions a mixture may be made 
which remains clear long enough to permit polarimeter 
observations to be taken. I dissolved 5 grms. of the tar- 
trate in 60 c.c. of water, cooled to 20**, and added five- 
tenths grm. of the tungstate in 20 c.c. of water. The 
mixture was made up quickly to 100 c.c. at 20^ and 
polarised in the 200 m.m. tube immediately and after 
inteivals of five minutes. I found without re-filUng the 
tube:— 



First observation an « xx'66^ 
Second „ X2*03' 

Third „ xa*i3** 

Fourth „ 12*53*' 

The solution became now too turbid, from separation of 
a precipitate, for further tests. On standing some honrs, 
the remainder of the solution in the flask cleared after 
subsidence of its precipitate. A portion of this examiDod 
gave— 

OD ■■ xa*74*. 

Another portion of the same solution, heated and then 
cooled to 20°, gave the same. A new solution prepared 
in the same manner gave, after standing some time, — 

OD = X3*ix°. 
I made next a solution containing in xoo c.c. 5 grms. of 
the tartrate and x grm. of the tungstate. This escamined, 
immediately, at 20", gave— 

OD= 9•4a^ / 
but it soon became turbid and deposited a precipitate. 
After clearing, I found — 

an « ix*48^ 
which increased to xi*87*' ^V heating the liquid. 

These reaAions are especially interesting when com^* 
pared with those between the tartrates and other salts. 
We have here, as before, a marked decrease in the 
specific rotation on mixing the solutions of the adive and 
inadive substances. But in the case of the tungstate, on 
standing, there is an increase instead of a decrease in 
the rotation observed in the other cases. This behavioor 
finds its explanation probably in the adion of the liberated 
tungstic acid. The reason between the two salts un* 
doubtedly follows this equation : — 
2KSbOC4H406+NaaW04= 

-2KNaC4H406+Sba03+(W03)*. 
The precipitation of the tungstic acid is very slow and 
incomplete. While in solution, it may combine with the 
soluble tartrate to form a body with increased rotation, 
the possibility of which is shown by the researches of 
Gernez and others. The delay in the appearance of the 
precipitate may be due to the formation and slow break- 
ing up of intermediate produAs containing the antimony 
and tungstic oxides in temporarily soluble condition. 
With liberation of the tungstic acid we have a gradual 
increase in the already decreased rotation. This chans^ 
in the rotation, before precipitation, is well shown in the 
following observations. I dissolved 5 grms. of the tar- 
trate and 2 and five-tenths grms. of the tungstate, mixed 
at a low temperature and made up to xoo c.c. as .before, 
and at exadly 20^ C. A reading with the 200 m.m. tube 
was made as soon as possible, and, without changingthe 
solution, this was repeated at frequent intervals. The 
results were as follows : — 

3 hours 28 minutes an « 5*66^ 

„ - 6*45° 
.. = 6*83<» 
„ - 7-15° 

3 hours 44 minutes „ » 7*43° 
3 hours 58 minutes „ » 7*90*^ 

At this point the liquid began to grow sliehtly turbid, so 
that the observations could not be continued. The re* 
mainder of the liquid was then heated in a closed flask to 
complete the precipitation, cooled to 20^, and tested. I 
found now — 

CD = 9*X3''. 
The liquid still remaining was filtered, 50 c.c. of the fil- 
trate taken and precipitated with hydrogen sulphide, 
yielding finally 04045 grm. of antimony sulphide. From 
this it appears that, of the tartrate originally taken, 1*599 



OntuiCAL Mtwt, I 
joly a6, tags-: f 



Action of Diastase on Starch.. 



4S 



grms. remained in solution in the zoo c.c. (no allowance 
being made for the volume of the precipitate). 
From this we have — 

KSbOC4H406|HaO decomposed « 3*401 grms. 

II II remaining 1*599 h 

KNaC4H406.4HaO formed 2*888 „ 

Now» the rotation corresponding to the tartar emetic 
rcmaiotng is 4*50% and that to the Rochelle salt formed 
is 1*25% from which we should expe^ a total rotation of 
5*75^ This, in fad, corresponds very nearly to what was 
observed at the beginning of the test, and seems to bear 
oat the suggestion made above : viz., that the principal 
reaAion here occurs before adual precipitation appears. 
A splitting of the tartar emetic is indicated by the imme- 
diate decrease in the rotation, and then the complex effeA 
of addition of the liberated tungstic acid to the alkali 
tartrate in solution appears from the gradually increased 
rotation. Precipitation finally follows as the end of the 
readion ; the separated part assumes the insoluble form. 

It will be recognised that the phenomenon in this case 
it much more complex than in the other. There is 
nothing to show that while the rotation is being increased 
by the adion of the tungstic acid there is not also a ten- 
dency toward decrease because of progressive decomposi- 
tion of the potaatitim antimony! tartrate. In all proba- 
bility the observed rotation is a resultant effed. 
(To bo cootioued.) 



PROCEEDINGS OF SOCIETIES. 

CHEMICAL SOCIETY. 
Ordinary Matingt yunt 20th, 1895. 

Mr. A. G. Vbrmon Harcourt, President, In the Chair. 

Extraordinary General Meeting. — The following change 
in the Bye-laws was proposed from the Chair, and passed. 

In Bye-law z, the last paragraph, beginning ** The life 
composition fee/* was struck out and the following in- 
serted:— 

** The life composition fee shall be Thirty Pounds, ex- 
cepting that Fellows who have paid ten annual subscrip- 
tions shall pay as life composition fee Twenty Pounds ; 
Fellows who have paid fifteen annual subscriptions shall 
pay Fifteen Pounds; Fellows who have paid twenty 
annual subscriptions shall pay Twelve Pounds ; and 
Fellows who have paid twenty-five annual subscriptions 
shall pay Ten Pounds.** 

At the ordinary Scientific Meeting which followed, 
Messrs. George J. Ward, John Wilson, E. S. Barralet, 
and W. A. Greaves, were formally admitted Fellows of 
the Society. 

Certificates were read for the first time in favour of 
Messrs. Edward Henry Farr, Uckfield ; Edward Henry 
Grossman, 12, Alfred Place West, S.W. ; C. E. Harrison, 
53, Lansdowne Road, W. 

The following were duly ele^ed Fellows of the 
Society :— John Croysdale, Joseph Lones, James Morison, 
Arthur E. Potter, M.A. B.Sc, Edwin James Read, B.A., 
Albert Joseph Simons. 

. Of the following papers those marked * were read :— 
•82. **On ihi •Isomaltou' of C. J. Lintmr:* By 

Horace T. Brown, F.R.S., and G. Harris Morris, 

Ph.D. 
The paper gives a detailed account of the authors' 

investigations into the nature of Lintner's <* isomaltose," 

and their results are summed up in the following conclu- 

8i(>n8:— 
jz. When the produAs of a starch-transformation by 

d^stase are submitted to any known process of fradion- 

iKioD, the properties of each and every fraAion stri^ly 



1 



conform to the ** law of definite relation '* of opticity and 
reducing power. 

2. The *' isomaltose " of C. J. Lintner is not a chemical 
entity, but can be further split up by careful fradionation 
with alcohol and by fermentation, in such a manner as to 
indicate that it is a mixture of maltost and dextrinoos 
substances of the malto-dextrin or amyloin class. We 
must therefore cease to use this term ** isomaltose" in 
relation to any of the produds of the diastatic conversion 
of starch. 

3. The crystallisable osaxone which Lintner has 
described as ** isomaltosazone,** and upon which he has 
mainly founded his belief in the existence of <* isomaltose,*' 
is nothing but ** maltosazone ** modified in its crystalline 
habit and melting-point by the presence of small but 
variable quantities of another substance. 

4. The substance or substances which are capable of 
thus modifying maltosasone are the prodnAs of the 
aAion of phenylhydrazine on the dextrinoos substances 
mentioned in 2. 

5. This can be shown (i) analytically, by careful frac- 
tionation of the starch-produas by alcohol, and also by 
fermentation ; and (2) synthetically , by the re-crystallisa* 
tion of pure maltosazone in the presence of the non- 
crystallisable produds of the aAion of piieoylhydrazine 
on the maltodextrins. 

6. The only substance amongst the produds of starch- 
transformation by diastase which is capable of yielding a 
crystallisable osazone, is maltost, 

7. The results of the investigation bring out very 
clearly the danger of attempting to identify the carbo- 
hydrates in mixtures solely by the properties of their 
osazones, as these properties are liable to considerable 
modification by other substances of the same class which . 
may not in themselves be crystallisable or readily sepa- 
rable from aqueous solutions. 

Discussion. 
Mr. Arthur R. Lino claimed priority on behalf of him- 
self and Mr. J. L. Baker In having pointed out that ' 
Lintner's so-called isomaltose is not a homogeneous 
compomid {Proc, Chem, Soc.^ 1895, 3)* In this commu- ^ 
nication they had also adduced strong evidence in fiavour 
of the view that the so-oalled isomaltose is a mixture of 
maltose and the simple dextrin, CxaHjoOio, and they had ' 
proved that the osazone melting at 150—252^ has the * 
composition of a hexatriosazone. 

82. •* Action of Diastase on Starch : Nature of Lintner* t • 
Isomaltose,''* By Arthur R. Lino and Julian L. Baker. 

In a previous communication (Proc, Chem, Soc, 1895, 
No. 146, 3) the authors have described the isolation of a 
substance from the transformation-produds of starch by 
the diastase prepared from low-dried or green malt. This 
substance had approximately the optical and cuptic re- 
ducing powers of Lintner's so-called isomaltose. Analyses 
and cryoscopic determinations made with this substance 
indicated that it had the molecular formula CtzUzzOu ; 
but the essential difference between it and the so-called 
isomaltose of Lintner was that it yielded maltosazone 
together with a very small quantity of an osazone melting 
at 145^x52° on treatment with phenylhydrazine acetate, 
whereas Lintner states that his compound yields a singit 
charaaeristic osazone melting at 150—152^ The authors 
have examined the low melting osazone obtained from 
their produA, and conclude that it is merely impure 
maltosazone. More recent experiments carried out by 
the authors support their view that Lintner's so-called 
isomaltose consists of a mixture of maltose and the 
simple dextrin, CxaHaoOzo {loc, cit,). No glucose is 
present among the produdls of the a^ion of diastase 
from low-dried malt on starch, and diastase from this 
source is without ad ion on maltose. 

It was previously shown {loc, cit.) that when starch is 
transformed at 70*" with the diastase prepared from kiln- 
dried or brewer's malt, the fradtion which should corre* 
spond with Lintner's isomaltose gives, 00 treatment with 



46 



Transformation of Ammonium Cyanale into Urea. 



fCRtmCALBlBWt, 
1 Joly a6, x89S. 



phenylhydracine acetate, glucosazone together with an 
osazone agreeing io crystalHne appearance and melting- 
point with the 80*ca]led isomaltosazone of Lintner, but 
having the composition Ci8H3oOx4(NaHPh)2t as if derived 
from a hixatriosit CxsHsaOxe. A diligent search has 
therefore been made for this triose among the transforma- 
tion produds last mentioned, but no crystalline compound 
has Deen isolated from them with the exception of maltose. 
Glucose was invariably present in small amount, and the 
Authors find that when maltose is treated at 7o° for two 
hours with the diastase prepared from high-dried malt, 
the presence of about 20 per cent of glucose is indicated 
by the increased cupric reducing power and the diminished 
optical adivity; glucose was also detedled qualitatively 
by the produdion of glucosazone. Bearing in mind the 
presence of glucose, as also their suggestion that Lintner*s 
isomaltose contains the simple dextrin, it occurred to the 
authors that the triosazone was possibly produced by the 
interadion of this dextrin and glucose with phenyl- 
hydrazine ; and this turns out to be the case. When the 
supposed isomaltose is treated with phenylhydrazine ace- 
tate in presence of glucose, the portion of the produdl 
soluble in hot water consists of a mixture of the trios- 
azone and maltosazone. 

'83. '* Thi TransformatioH of Ammonium Cyanats into 
Una:* By Jambs Walker, D.Sc, Ph.D., and F. J. 
Hambly. 

The transformation of ammonium cyanate into urea is 
re?ersiblei about 5 per cent of urea in decinormal aqueous 
solution at 100* being re-transformed into ammonium 
cyanate. The dired transformation obeys the laws of a 
bimoleculer readion, and not of a unimolecular readion, 
as might be expeded. This is accounted for by the as- 
sumption that the ammonium cyanate is largely dissoci- 
ated into ammonium ions and cvanic ions, and this 
assumption is confirmed by the influence of ammonium 
sulphate, potassium sulphate, potassium cyanate, and 
other substances, on the rate of the readion. The dis- 
sociation theory also enables us to calculate the quanti- 
tative phenomena taking plnce when the transformation 
of urea into ammoninm cyanate occurs in presence of 
silver nitrate. The speed of the readion varies greatly with 
the temperature, and the variation may be expressed by 
means of van *t Hoff's formula. 

'84. '* NoU on thi Transformation of Ammonium 
CyanaU into Urea:* By H. J. H. Fbnton, M.A. 

Some years aeo the author made a short communica- 
tion to the Canabridge Philosophical Society upon this 
subjed. (** The Metameric Transformation of Ammonium 
Cyanate/' Proc, Camb, Phil. Soc, 1888, 307.) Details of 
these experiments were not published, as it was intended 
to make further experiments. The reason for giving these 
details in the present note is that, in the list of papers to 
be read*at the present meeting, there is one which has the 
above title, and it was thought that the obtervations 
might be of interest to the authors. Unfortunately the 
Prociidings of thi Cambridge Philosophical Sociity are 
not often seen by chemists outside Cambridge, so that it 
is hardly to be expedted that these authors should be 
aware of this communication. 

In a previous paper {Trans, Chim, Soc.t 1878) I showed 
that urea when treated with sodium hypochlorite, in pre- 
sence of caustic soda in the cold, evolves only one-half of 
its nitrogen in the free state, the remainder being retained 
in form of cyanate. The latter gives no nitrogen with 
hypochlorite or hypobromite. 

Ammonium cyanate was prepared by dired union of 
cyanic acid vapour and dry ammonia. Weighed portions 
of this salt were aded upon by sodium hypobromite and 
hypochlorite, and excess of soda, with the following 
results :— 

With sodium hypobromite— 

I. 0*0544 grm. AmCyO gave 9*3 c.c. nitrogen (corr.). 
II, 0-0562 „ „ „ 9»93 „ „ 



Since with hypobromite estimations, as conduced io 
the usual way, there is a deficiency of about 8 per cent 
in the nitrogen evolved, a correAion for this was applied, 
giving (I.) lo'io c.c, and (II.) 10*79 c.c. Theory for haljf 
the nitrogen requires lO'Zi c.c. and 10*45 c.c. respedively. 

With sodium hypochlorite- 

Theory 

0*0620 grm. AmCyO gave zx*89 cc. nitrogen (corr). 11*53 
00692 „ „ 13*08 „ „ 12-87 

00905 „ „ i6*34 f. 1. »683 

It is evident, therefore, that this salt evolves only half its 
nitrogen in the free free state with either reagent. 

These fads obviously suggest a method by which it is 
possible to estimate the extent to which ammonium cya- 
nate has been transformed into urea. 

Let V s volume of nitrogen obtained by the adion of 
hypobromite when a given weight of ammonium cyanate 
is taken and partly or entirely converted into urea ; and 
let Vt = total volume of nitrogen contained in the sub- 
stance taken, Then the nitrogen due to the urea formed 
will be 2V— Vx. For convenience the percentage trans- 
formation may be expressed as 2V— Vx/Vxxzoo. 

Applying this method, the following results were ob- 
tained : — 

0*7632 grm. AmCyO was dissolved in water and the 
solution made up to 100 c.c. 10 cc. were taken 
for each experiment. 



Temp. 
I. Ordinary 
(about 19*) 

III. 37' 



Vol. of N, Theory for Trant- 
Time, (corr.) | N,. formakioa. 

Immediate 14*14 14*19 None 



x8 hours 19*0 — 33*8 

3 days 20*54 — 447 

0*5561 grm. AmCyO dissolved in water and made up 
to 100 c.c 10 cc taken. 



I. Ordinary 
II. — 
III. ioo« 



20 hours 



10*34 2o*3 



II. 
III. 



Z2*6o 
Z2*28 

17-57 — 69^ 

I9'03 -^ 84*0 

19*50 — 88*5 

0*9495 AmCyO in xoo c.c. 10 cc taken. 

70° I hour 25*9 17*66 46*6 

4 hours 28*5 — 61*3 



100" 
100** 



I hour 
2i hours 
20 hours 



7o« 



40 hours 



30-4 — 



72" I 



In each case the liquid was measured into a small, 
partly drawn off test-tube, which was .afterwards sealed. 
A corredion for the loss of 8 per cent is made in the 
stated volumes of nitrogen. 

These results indicate that the change proceeds rapidly 
at first, then becomes slower, and finally reaches a limit 
which is a fundion of the temperature. In no case 
examined was the transformation complete. 

These fadls suggest that the aAion may be a reversible 
one ; urea and ammonium cyanate are perhaps tautomeric 
forms transformable one into the other. This hypothesis 
would account for some of the properties of urea which 
are otherwise difficult to understand. For example, the 
difference in the aaions of hypobromite and hypochlorite 
(in presence of soda), mentioned above, might be explained 
in the following way :~The adion of hypobromite is 
nearly instantaneous, whereas that of hypochlorite is ex- 
tremely slow. The solution of urea may contain ur^ 
and ammonium cyanate in a state of equilibrium, lift 
urea, of course, largely preponderating. Hypobromit t 
therefore evolves nearly all the nitrogen — all from th 1 
urea, and half from the ammonium cyanate. Hypochlorite ^ 
however, it may be supposed, attacks only the ammoniui' i 
cyhuate, liberating half of its nitrogen, the other half r^ > 
maining as cyanate which is not further decomposer i 
This would destroy the equilibrium of the system, and \ r t 
further transformation of urea into ammonium cyanat< \ 
would result. The latter would be removed as before, anr ( 






CHIMlCAt NlWf, \ 



New Formation of Glycollic Aldehyd. 



47 



i 



finally one-half ol the total nitrogen would be evolved in 
the free state, 

There are indications also that cyanate is produced 
when nrea solution, mixed with potash in excess, is left 
to stand for several weeks in a bell-jar over sulphuric 
acid. This fad could be explained in a similar manner. 

*85. " Somi Dtrivativn of HumuleneJ'^ By Alfred 
C. Chapman. 

In a former communication (Trans, Chtm, Soe., 1895, 
Uvii., 54) the author described a sesquiterpene obtained 
from the essential oil of hops by fradional distillation, for 
which he suggested the name humulene. In that paper a 
nitrosochloride (m.p. 164—165°) was described, and also 
m aitrol-piperide obtained from it (m.p. 253°). 

In the present paper the author gives an account of the 
following additional humulene derivatives : — 

Hydrockloridt of humuUm nitrolpiperide — 
(C,3Ha4NONC3Hxo.HCI). 
»-This was obtained by passing dry hydrogen chloride into 
a solution of the nitrol-piperide in ether. The platini- 
chloride of this salt crystallising from alcohol in reddish 
needles was also prepared (m.p. 187 — 189**). 

HumuUm nitrol-benMylaming — 

(C,3Ha4NONHCHaC6H5). 
^This compound was obtained by heatin£| humulene 
nitrosochloride with an excess of bensylamme. After 
crystallisation from boiling alcohol it melted at 136*. 
The hydrochloride of this base was prepared by passing 
hydrogen chloride into an ethereal solution of the com- 
pound (m.p. 187— 189*"). 

Hnrnultm niirosati (Cx3H22Na04).~ Prepared by ading 
with nitric acid upon a mixture of humulene and amyl. 
nitrite in glacial acetic acid. It crystallises from benzene 
in small colourless needles, melting at 162 — 163^ 

Humuhni nitronti (Ci3H24Na03). — This compound 
was prepared by allowing nitrous anhydride to combine 
with humulene dissolved in petroleum ether. After one 
rc-crystallisation from boiling alcohol the compound was 
obtained in the form of magnificent deep blue needles, 
melting at about 120*). The mother-liquor from which 
this compound separated deposited colourless needles, 
which, after re-crystallisation, melted at x66 — 168^, and 
were found to be isomeric with the blue compound. This 
Utter could be almost completely converted into the 
white substance by the long-continued boiling of its alco- 
holic iolntion. 

•86. •• Not4 on Thlo-dtfivatiats from Sulphanilic Acid,'* 
By L. Edna Walter. 

When diazotised sulphanilic acid and potassium xan- 

thate are allowed to interad, following Leuckart*s 

diredions {jf, Pr, Chem., 1890, xli., 179), the parasul- 

phonate-xanthate of the formula SOjKCsHvS'CS-OEt 

IS readily formed as an easily soluble crystalline sale. On 

hydrolysis this xanthate undergoes change in two ways, 

and yields both the sulphydride, SOsK*C6H4*SH, and the 

sulphethide, SO^K*C6H4*SEt. As the former, however, is 

very readily oxidised, the corresponding disulphide is 

nscally obtained. When acid is used in efleding hydro- 

lyiis, the disulphide is the only produA ; but when alkali 

it used the produA is a mixture which apparently is the 

richer in sulphethide the more concentrated the alkali. 

^ When the dried xanthate is heated at about 200* it 

loses considerably in weight, being converted into the 

jbnlphethide, which is more easiljr prepared in this way : 

, only a small amount of disulphide is produced in this 

case. 

The potassium disulphide crystallises in needles ; it is 
. very soluble in water, and sparingly soluble in alcohol. 
' ft yields a crystalline sulphochloride melting at 142% and 
a aalphonamide melting at 253*. 

The potassium sulphethide is very soluble in water and 

; in alcohol ; it crystallises in six-sided plates. The ba- 

rltttn salt crystallises in very charaderistic rhombic 

J plates ; its sulphochloride melts at 33% and its sulphon- 

■ amiae at i34'. 



The sulphethide is converted by oxidation with per* 
manganate into the corresponding sulphonate, which is 
soluble in water, and yields a sulphochloride melting at 
103-5^ 

The sulphide, on the other hand, very readily yields 
benseneparadisulphonate when oxidised by permanga- 
nate. The xanthate may also be dtredly converted into 
paradisulpbonate by oxidation with permanganate, and it 
is easy in this manner to prepare any desired quantity of 
bcnzeneparadisulphonic acid. 

One disulphochloride, C6H4(S02Cl)a. prepared from the 
produA, fuses at 136*5, several degrees higher than the 
melting-point assigned by Kdmer and Monselise. 

*87. **ffWfNM, a Constiiuint of drialn Minerals.** 
Part II. By William Ramsay, F.R.S.t J. Norman 
Collie, Ph.D., and Morris Travers, B.Sc. 

The first part of this communication contains an ac- 
count of the sources of helium. About thirty minerals 
have been investigated, mainly those containing uranium, 
and of these fifteen contained helium in greater or less 
amount. Many, in addition, evolved hydrogen, s hydro- 
carbon, and carbon dioxide. 

The second part treats of the densities of samples 
from different sources. After purification, the value a*a 
was obtained for three samples— one from d^veite, one 
from brdggerite heated alone, and one from br6ggerite 
fused with hydrogen potassium sulphate. It was proved 
during these experiments that hydrogen is not evolved in 
combination with helium by the a^ion of acid on mine- 
ral containing helium. The density of all these samples, 
united and carefully purified, was 2*ai8 ; a second puri* 
fication made the density 2*228, pradically an identical 
number. 

The wave-length of sound in the gas corresponds sccu* 
rately to the ratio x : i}, implying monatomicity, if that 
be granted to mercury on the same and on different 
grounds. The atomic weight would therefore be 4*4. 

The solubility in water is 0*007 at x8*. Helium is 
therefore the least soluble of gases. It is insoluble in 
alcohol and in benzene. 

The paper concludes with a discussion of the relations 
of helium towards other elements. 

88. ** Niw Formation of GlycoUie AUUhydi.** By H. J. 
H. Fenton, M.A. 

The properties of the acid C4H406*2Ha0, which was 
described by the author in a previous paper {Trans, Chnm* 
Soc, 1894), A>^ Btill being investigated with a view of 
establishing the constitutional formula for the acid. The 
present paper deals with the decomposition which the 
acid undergoes when heated with water. It is shown 
that, under these circumstances, glycollic aldehyde and 
carbon dioxide are produced, the change taking place 
almost quantitatively according to the equation — 

C4H406= CaH40a-h2COa. 
The glycollic aldehyde was identified by oxidation to 
glycollic acid and by the adion of excess ol phenyl- 
hydrazine acetate, which gave the phenylosasone of 
glyoxal.— 

CHNaHCeHj 



c!. 



HNaHCsHj. 

This decomposition affords a very simple method for 
the preparation of glycollic aldehyde. 

Bv spontaneous evaporation of the aqueous solution 
(and purification from a trace of glyoxylic acid produced) 
the aldehyde was obtained in an isolated condition as a 
viscid syrup, pure, except for a trace of ether or alcohol, 
which is obstinately retained. On removing this ether by 
heating under reduced pressure, the aldehyde undergoes 
polymerisation, a sweet-tasting solid gum being the re- 
sult. Molecular weight determinations indicate that this 
substance is a form of hexose, C^HiaO^. It reduces 
Fehling's solution in the cold, and gives an osazone 
melting at 162—163". 



48 



Dissociation of Gold Chloride. 



f CamtcAt Riwt, 

I July 26, 1895. 



89. " Ethertal Salts of Ethanetttracarhoxylie Acid,'** 
By James Walker, Ph.l>., D.Sc, and J. R. Appleyard. 

Symmetrical dimethylic dihydrogen ethanetetracat- 
boxylate should, according to Btereocnemical theory, exist 
in an inadive and a racemic modification, and the corre- 
sponding potassium salts should yield, on eleArolysis, 
dimethylic maleate and dimethylic fumarate respedively. 
An attempt was made to separate the two modifications, 
but it was unsuccessful. The mixed dimethyl dipotassium 
salts, on eledrolysis, gave a small quantity of dimethylic 
fqmarate. The following derivatives of tthanetttracat' 
hdxylic acid were prepared in the investigation. Tetra- 
methylie ialt, m. p. 104*, symmetrical. Dihydrogtn 
dimethylic saltf m. p. 158— 160*^ with decomposition. 
Tfii'thylic moHomethylic salt, m. p. 58'. Die thy lie dime- 
ihylic salt, liquid. 

90. *' On the Occurrence 0/ Argon in the Gases Enclosed 
in Rock Salt, By P. Phillips Bedson, M.A., D.Sc., and 
Savillb Shaw. 

The brine obtained from the wells sunk in the rock salt 
deposit on the north bank of the Tees, in the neighbour- 
hood of Kf iddlesbrough, when pumped to the surface is 
found to be strongly effervescent. The gas, the liberation 
of which gives rise to this phenomenon, had been ana- 
IjMed by one of us some years ago (7. Soc, Chem, Ind,, 
1888, 660 to' 667), and found to consist ol^ 

By volume. 
Methane •• •• •• •• 2*05 

Nitrogen 97*95 

100*00 
It was thought that a re- examination of this gas, with 
a view of testing its freedom or otherwise from argon, 
would be of interest. Through the kindness of Mr. 
Alfred Allhusen, a fresh sample was accordingly procured 
in May of the present year, when it was found to have 
slightly altered in composition and to contain- 
By volame. 

Oxygen x*3 

Nitrogen .. •• •• •• 9^*7 

lOO'O 

only a minute quantity of methane being present, and the 
small amount of oxygen ptobably due to air leakage. 

Professor Ramsay kindly furnished details of the sim- 
plest method for ascertaining the presence of argon in 
the gas—'* sparking '* over caustic soda in presence of 
oxygen, and submitting the residue after contraAion 
ceased to spe^roscopic examination. A small indu^ion 
coil, giving a fin. spark in air and aduated by the cur- 
rent from a battery of storage cells, was employed. 
About 40 c.c. of the gas was submitted to examination 
in each experiment. The sparking was continued in 
presence of an excess of oxygen until no further contraAion 
was noticeable. After this it was found necessary to 
continue the sparking for an hour or two, until examined 
spedroscopically the nitrogen lines, which grew fainter 
and fainter, finally disappeared. After absorbing the 
excess of oxygen present with alkaline pyrogallate, the 
small residue was added to an already measured volume 
of pure oxygen, and the whole accurately measured, using 
the apparatus of Professor Dittmar in conjundion with a 
form of Lunge volumeter. 

Two estimations gave results as follows :— 

II I'aeol ^**° "^ '^ P^^ ^^^^ ®^ argon. 
The amount of argon present in the nitrogen from the 
rock salt is thus pradiically identical with the amount 

Cisent in the nitrogen of ordinary air as determined by 
rd Rayleigh and Professor Ramsay. This is to the 
authors* knowledge the first recorded analysis of a sample 
of naturally occurring nitrogen which has been stored up 
for some thousands of years under conditions which prac- 
tically preclude the possibility of change. The nitrogen 
was probably in the first instance derived from the atmo- 



sphere, and it is of considerable interest to note that 
atmospheric nitrogen at the present day is still associated . 
with the same percentage of argon as when in remote 
ages it was first occluded in cavities in the rock salt. 

As Professor Ramsay has shown that argon is soluble 
to a considerable extent in water, it is proposed to exa- 
mine the gas given off on boiling the orine after effer- 
vescence has subsided. In this way a gas would probably 
be obtained much richer in argon, and, as there would be 
little difficulty in procuring it in quantity, it might prove 
a useful source of the new gas. It is also proposed to 
submit the nitrogen found enclosed in coal to a similar 
examination. 

91. " On the Dissociation of Gold Chloride.'^ By T. K. 
Rose, D.Sc, A.R.S.M. 

The tensions of dissociation of trichloride of gold at 
various temperatures up to 332° were measured, the 
limited chemical adion investigated being expressed by 
the equation — 

AuCls;^AuCl + Cla. 

The total pressures observed when a mixture of AuClj 
and AuCl is heated in a closed space are higher than the 
tensions of dissociation, owing to the vapour- pressure of 
AuClj, which becomes considerable between 200" and 
390**. The attainment of the maximum pressure is greatly 
delayed if the substances are carefully dried. 

An investigation by means of Deville*s ** hot and cold 
tubes'* showed that AuClj undergoes continuous volatili- 
sation in chlorine gas at atmospheric pressure at all temper- 
atures between x8o^and xxoo"*, the limits of temperature 
employed. The curve illustrating the rate of volatilsation 
under these conditions passes through a maximum at about 
30oS and a minimum between 800^ and 900^ Reasons 
for the shape of the curve are adduced. 

The results afford evidence that Kriiss's statements on 
the decomposition and volatilisation of gold chloride can- 
not be substantiated, but that those of Boyle and of Debray 
are in accordance with fad. It is pointed out that, ac- 
cording to the laws of chemical equilibrium, compounds 
formed with evolution of heat cannot be included in the 
class of bodies which are completely decomposed at mo- 
derate temperatures and again formed at much higher 
temperatures. The statements of Kriiss regarding the 
behaviour of gold chloride at various temperatures, and 
those of Langer and V. Meyer regarding platinum 
chloride, are therefore at variance with theory, and in the 
former case have been shown to be unfounded. 
(To be continued.) 



NOTICES OF BOOKS. 

Chemists and their Wonders, The Story of the Applica- 
tions of Chemistry to various Arts and Manufadures. 
By F. M. Holmes. London: S. W. Partridge and 
Co. Crown 8vo., pp. x6o. 
The reader will find here a readable, bright, and moM 
instrudive survey of the services which chemistry ^ 
rendering to civihsation. It is drawn up in the form of 4 
conversation between several interlocutors, one of whom', 
aptly spoken of as ** Mr. Flippant,*' does not think much 
of chemistry until fairly beaten off the field. He pleads * 
that ** chemists don*t build bridges or make railway 
trains ! " We may here mention that there exists in the 
minds of County Councillors, &c., a delusion that 
chemists are inferior to engineers, and they even hand 
over to the latter work which can be done aright only by 
the former. Thus, when the manner of disposing of the 
sewage of London was under discussion, it was proposed 
that the task should be assigned to the engineer who had 
construded the Tay Bridge! 

Another school of unqualified censors accuse us of 
*' imperfed drainage, of devising benumbing poisons, and 



'""yAi«!ST*'> Chmtcal Notices from Foreign Sources, 



•49 



cobtrtviog infernal machines." Whilst a third, though 
kindred, fadion think that we might be good and happy 
without any knowledge of rare earthi, or even if they had 
no existence. Our author does much to sweep such cob- 
webs out of the heads of all sensible people. 

In his sketch on the rise of alchemy, however, he con- 
cede! too much to the old notion that this romantic delu- 
sion was the parent of chemistry. This question has 
be6n of late exhaustively discussed by the great French 
savant Berthelot. A little further Mr. Holmes touches 
on the peculiarly English error that chemistry is especially 
conneded with drugs and medicines. This mistake is 
due to the unfortunate fad that in these realms the 
dealers in, and compounders of, medicines have contrived 
to appropriate the term ** chemists" in place of their 
legitimate name, ** pharmacists." 

In the vork we find an exposition. of the most salient 
features of the lives and researches of Boyle, of Lavoisier, 
Chevreul, of John Young (of ** paraffin " celebrity), of 
John Walker, of Schcele, of W. Murdoch (the gas manu- 
fadurer), with his predecessors, Shirley and Clayton, the 
latter dating back to 1739. Winzer, or Winsor as he re- 
named himself, receives mention, and though he did not 
invent gas, was the inventor of gas companies— a blessing 
for which chemical science can scarcely be held respon- 
sible. 

The expression here used of " enriching " coal-gas with 
both oil-gas and water-gas is misleading. Water-gas, 
sometimes spoken of as " Dowson gas," enriches coal- 
gas chiefly in the deadly produd carbon monoxide. A 
speaker here doubts whether it would answer well in 
England if used alone. The reason is because our sani- 
tary laws are more stringent than those of the United 
States. 

'** High " explosives receive a very full notice. As a 
set off to the fearful dangers consequent upon any over- 
sight or irregularity in their manuiadure and use, it it 
here pointed out that the dynamitards and anarchists are 
liable to fail from the difficulty of manufaauring a safe 
article without an amount of care not easily secured when 
the process is carried on illegally. It is, however, to be 
again remembered that the dangers of ill-made dynamite 
do not always fall upon the guilty parties. It may be 
asked whether the economy of time and labour from the 
> use of the high explosives in place of gunpowder, is a 
sufficient compensation for the destrudion of life and pro- 
perty attending upon their employment. 

Other ably-written and luminous chapters treat of the 
coal-tar colours, of photography, of indiarubber and its 
transformations, of chemical manures, of aerated water, 
and of disinfedants and germicides. 

Few of the outside public, even of the so-called " intel- 
ligent and respedable classes," can read these chapters 
without having their eyes opened, literally and, even still 
more, figuratively. It might, of course, have been briefly 
pointed out that our disgraceful inferiority in the manu- 
fadure of the coal-tar colours is due to the joint adion of 
two causes : the fad that our students instead of being 
trained in discovery, are compelled to waste their time 
and energ;ies in '* preparing for exams." ; and, secondly, 
to the laxity of our laws, which allow an alien to hold a 
British patent without attempting or intending to put it 
IB use on British soil. 

The work before us merits the warmest recommenda- 
tion. 



CHEMICAL 



NOTICES FROM 
SOURCES. 



FOREIGN 



CompUs Rendus Ilebdomadaires des Seances, de VAcademie 
des Sciences, Vol. cxx., No. 25, June 34, 1895. 
Farther Studies on the Fluorescence of Argon and 
0n its Combination with the Elements of Beosene. 
^*M. Berthelot.— (See p. 13). 



On the Ladtones or Campholenic Olidea.— MM. 
Berthelot and Rivals. — It results from the author's re« 
searches that the ladones have formation-heats notably 
superior to those of the isomeric acids ; the deviation 
measured between the liquid acid and the inadive ladone 
being 143*8 - 1317 « +I2'i. 

Solution of Neutralisation Heats of the Campho- 
lenic Acids.— M. Berthelot.^The author has determined 
the heats of the liquid and solid campholenic acid and of 
campholic acid. 

Redudtion of Silica by Charcoal.— Henri Moissan. 
— M. Moissan has obtained a very decided redudion by 
heatine a mixture of rock-crystal and of carbon in powder 
in a cylinder of coke closed at one end. If the tempera* 
ture is not very high a part of the silicon escaper the 
adion of the carbon, and is found in the state of crystals 
or of fused globules. This procedure may be applied to 
the preparation of silicon by refrigerating its vapour at the 
moment of produdion. 

Condensation-produdts of Valeric Aldehyd (Methyl 
a-Butanal-4). Observations concerning the Paper of 
Barbier and Bouveault.— C. Friedel.— The author has 
been for some time engaged with a study of the conden* 
sation-produds of valeric aldehyd by the adion of dilute 
soda, aqueous or alcoholic. One of these produds is the 
substance which Barbier and Bouveault regard as di- 
me ihyl-26-heptene-3-methylal-3, and which they have 
further condensed with acetone. 

Properties of Solid Carbonic Acid.— P. Villard and 
R. Jarry.— Dry carbonic acid was distilled and solidified 
in a wide refrigerated tube in which a* thermometer had 
been introduced axially. The melting-point of the solid 
acid was -567^ The pressure at the time was 5*1 atmo* 
spheres. The point of refrigeration was then observed 
and found to be —56*7° at the pressure of 3'x atmospheres. 
This result agrees substantially with the figures found by 
Faraday. The point of ebullition of solid carbonic acid is 
at -79^ Regnault found -78*16 and Pouillet -7^. 
Ether mixed with solidified carbonic acid (carbonic snow) 
does not reduce the temperature. Methyl chloride behaves 
quite differently: setting out from -65^ the carbonic 
snow dissolves without liberation of gas, and^ at the mo- 
ment of complete saturation the thermometer macks -^ 85^ 
The lowest temperature reached by means of carbonic 
snow m vacuo is -1x5^ a point which was maintained 
for neariy three hours. 

On a Formula of M. Quye.— A. Colson.— Referring 
to a paper by Guye and Jordan (CompUs Rendustp. 1274) 
the author holds that the simplified formula of Quye is 
unfounded, and that the diredion of the rotatory power is 
not indicated in a satisfadory manner by a formula 
founded solely upon chemical hypotheses. 

On the Alcohols Derived front a Dextro-Tersbea- 
thene, Bncalyptene.— G. Bouchardat and Tardy.— An 
attentive study of the derivatives of the various natural 
terebenthenes with different rotatory powers will probably 
enable it to be established that these carbides are merely 
mixtures of two adive turpentines, dextro- and lasvo* 
rotatory, meeting each other in variable proportions. 

Condensation of the Non-saturated Aldehyds of 
the Patty Series with Dimethylacetooe ; Synthesis 
of Aromatic H>drocarbons.— Ph. Barbier and L. Bou- 
veault.— The authors consider the condensation of methyl- 
ethylacroleine with acetone and the condensation of aiso- 
propyl-j3-isobutylacroleine with dimethylketone. 

Double Combinations of the Nitriles belonging to 
the Fatty Series acd to the Aromatic Series with 
Aluminium Chloride. — Q. Perier.— This memoir is not 
adapted for useful abridgment. 

Ad\ion of Air upon the Must of Grapes. — V. Mar- 
tinand. — Of all the elements of must the red soluble 
colouring matter is the most readily oxidisable. In grapes 
of the type of the Petit-Bouschet there eaists a colouring 
matter oxidisible by air, and one which is less BO or n(U 



i'' 



50 



Chemical Notices from Foreign Sources. 



{Chbiucal Nbwi, 
Jaly26, X895. 



tt all, and which does not hinder the a^ion of the air 
from proceeding upon the other elements of the must. 
The bouquet of wine is due not only to the bouquets which 
exist pre-formed in the grape and to those developed 
daring the fermentation, but also, in some varieties, to the 
elements contained in the mutt. The colouration of white 
wines and their taste are due to an oxidation of the must, 
and are not derived from fermentation. It is possible to 
prepare white wines with black grapes by extrading the 
total Juice which they can yield, and submitting it, before 
fermentation, to the following operations : — Refrigeration 

■ to check fermentation, aeration to precipitate the colouring 
matter, and, lastly, filtration of the liquid to prevent its 
fe-cokmration during fermentation. 
Treatment of the Bites of Venomous Serpents by 

' Chloride of Lime and by Anti-venomous Serum. — A. 
Calmette. — MM. Phisalix and Bertrand erroneously as- 
cribe to the author a view which he repudiates, i. e,, that 

~ chloride of lime has a vaccinal adtion. Conclusive experi- 
ments with chloride of lime have been made successfully 
upon human subjeAs, especially by Prof. Halford, at Mel- 
bourne. He is now sending out immunising serum in 
considerable quantities to India, the Antilles, and Aus- 
tralia. It is sufficient to injeA into rabbits a dose of the 
serum equal to i-io,oooth of their weight to enable them 
to bear afterwards, without danger, a dose of venom 
capable of killing check specimens in from three to four 
hours. 



J. & A. CHURCHILL, 
PU BLISHER S. 

PRACTICAL CHEMISTRY AND 

QUALITATIVE ANALYSIS; SpeciftUy adapted for CoUena 
and Scbaols. By FRANK CLOWES. D.ScMJProfMaor of cCe- 



mistry in Univeraity College, Nottingham. 
84 Engravings, Poat 8vo, &. 6d. 



Sixth Edition, with 



MISCELLANEOUS. 

Inttttttte of Chemistry.— The following Candidates 
have passed the Examinations for Membership, July and 
to July 5th, 1895 :—Fcr tkt Fillowthip : Fuerst, Alexander 
Frankenbacher (Ph.D.» Heidelberg), The University of 
Heidelberg. For thi Atiociattship (under Regulations in 
force prior to OAober ist. 1893) : Andrews, Ernest Robert, 
Finsbnry Technical College; Barnes, Charles Kepler, 
University College, Liverpool ; Bodey, Augustus Charles, 
University College, Bristol, and Pharmaceutical Society's 
Research Laboratory; Bowie, James Girdwood, Mason 
College, Birmingham ; Bowles, Horace Edgar, Finsbury 
Technical College ; Buchanan, John, Glasgow and West 
of Scotland Technical College ; Burbridge, James Kerry, 
King's College, London ; Desch, Cecil Henry, Finsbury 
Technical College ; Dodd, Frederick Robertson, Glasgow 
and West of Scotland Technical College, and Registered 
Student under A. Smetham, Esquire, F.I.C. ; Guthrie, 
Thomas, Yorkshire College, Leeds ; Hill, Charles Alex- 
ander. Pharmaceutical Society's Research Laboratory, 
and King's College, London (Physics); Hirst, Henry 
Reginald, Yorkshire College, Leeds; King, Herbert, 
Yorkshire College, Leeds ; Meggitt, Loxley, University 
College, Nottingham ; Ridding, Howard Charles (Assoc. 
R.S.M.). Royal College of Science, London ; Warden, 
John Blair, Glasgow and West of Scotland Technical 
College, and School of Mines, Freiburg; Wharton, Fred- 
erick Malcdlm, Mason College, Birmingham; Woollatt, 
George Henry, University College, Nottingham, and 
Royal College of Science, London. Final Examination 
for thi Associatiship (New Regulations) : Robins, Walter 
(B.Sc Lond.), Finsbury Technical College. 



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O BMICAX. NBWt, I 

Aug. a, 189S. I 



Possible Compound of Argon. 



51 



THE CHEMICAL NEWS. 



Vol. LXXII., No. z86a. 



A POSSIBLE COMPOUND OF ARGON. 
By WILLIAM RAMSAY, P.R.S. 

There are three ways of forming an endothermic com- 
pound. First, by choosing such a readlion as shall on the 
whole give rise to heat-evolution ; as when potassium 
hypochlorite is produced by passing chlorine into a solu- 
tion of caustic potash ; water and potassium chloride are 
produced simultaneously with great heat-evolution, so 
that the algebraical sum of heat is positive. A second 
method is to use the silent discharge ; and by this means 
oxygen can be oxidised into ozone. A third method de- 
pends on the faA that an endothermic compound is more 
stable at high than at low temperatures, and that if it can 
be suddenly withdrawn from a hot region a certain pro- 
portion, at least, will escape decomposition. By this 
means acetylene can be produced by causing an arc to 
play in an atmosphere of hydrogen. 

The first of these methods would appear to be impos- 
sible with argon. No definite compound is known ; much 
less one produced with heat-evolution. 

The second method has been used apparently with 
tome success by M. Berthelot. 

The third method has recently been tried ; and though 
much remains to be done, circumstances render it de- 
sirable that I should record in a preliminary note certain 
results which I have recently obtained. 

The arc was made m vacuo between two thin carbon 
rods, enclosed in a globular bulb ; this was in order to 
expel, to a certain extent at least, occluded gas. The 
bulb was then filled with argon, and placed in communi- 
cation with a graduated reservoir of dry argon. After 
some four hours, in which the pressure was always some- 
what above that of the atmosphere, so that leakage in- 
wards could not have occurred, all was allowed to cool. 
The volume of the gas had increasid by about one-fifth. 
No alteration of volume was caused in this gas on ex- 
posure to water, to caustic soda, or to ammoniacal 
cuprous chloride; hence the gas contained no carbonic 
anhydride or oxide. The spedrum of this gas, while 
showing a faint argon spe^rum, exhibited a very finely 
channelled speAruro, so luminous as to give the im- 

{iression of a continuous spedlrum, together with certain 
ines which are not coincident with arson lines, judging 
by a careful comnarison in which both speara were in 
the same field. Mr. Crookes has kindly undertaken to 
examine the spearum, and will doubtless report on it. 

Further experiments will be made ; but I must content 
myself at present with chronicling the few fads which I 
have observed. 

UoiverBity College, Qower Street, 
jBly a^ X895. 



OPENING UP 
PURE 



SILICATES BY MEANS OF 
LEAD CARBONATE. 
By P. JANNASCH, 



The first chemist who made a successful attempt to de- 
compose silicates quantitatively by fusion with lead oxide 
was,G. Bong (Zeit.f, Anal, Chtmitt xviii., p. 270). Sub- 
seqiAently W. Hempel and R. F. Koch {Ibid. , xx., p. 496) 
gavel the preference to bismuth oxide. Recently I had 
the opportunity to experience the advantages of the use 
of lejid oxide when effe^ng the analysis of some speci- 
men*^ of topaz ID concert with H. Jas. Locke. The many 



eat) ( 

i 



experiments which I have lately made on incinerating 
and weighing lead- and bismuth-oxides in platinum 
vessels, induced me to attempt the opening up of silicates 
by direa mixture with pure lead carbonate and subsequent 
fusion in a platinum crucible. From these very success- 
ful experiments there originated the following general 
procedure for the analysis of silicates. 

The requisite chemically pure lead carbonate is snitably 
obtained by precipitating a hot solution of lead acetate 
with the calculated quantity of ammonium carbonate. 

The granular precipitate obtained is first washed in a 
tall beaker by repeated decantation, then distributed on 
!*^yf ^?^ ?P'^ ^^'*" <"^*^® ^y I^esaga. of Heidelberg) not 
Jolded filten, perfeAly washed with boiling waters, 
finally with sudion, carefully removed from the paper 
without injuring it, and finally completely dried in a 
capacious porcelain capsule at the heat of the water-bath 
and With stirring. 

For opening up silicates I use a large thick-sided 
platinum crucible, of 52 to 53 m.m. in height, 45 m.m. in 
width at the top, and weighing, together with its cover, 
72 grms. We thus obtain better melts, and most com- 
pletely avoid the volatilisation of traces of alkali. 

For effeding the fusion we put into the crucible from 
ten to twelve times the quantity of dry lead carbonate, 
add the very finely pulverised and air-dried specimen 
(which has been weighed in a small tube), and mix iho- 
roughly with the glass rod, and heat the whole— under 
cover, at first gradually, approaching the crucible with a 
flame of an inch in height for about fifteen to twenty 
minutes, whereby the greater part of the carbonic acid 
escapes ; it is then more strongly heated to fusion at red- 
ness, but only about one-third of the height of the 
crucible must be adlually red-hot. It is remarked that if 
the silicate contains organic matter, this must be first 
destroyed by gentle ignition before admixture with lead, 
carbonate. It is also stated that the platinum crucible 
is less attacked than by a fusion with sodium carbonate 
or an alkaline hydrosulphate. 

Care must be taken to use a thoroughly non-luminous 
flame, so as completely to obviate any aaion ol redudive 
gases upon the contents of the crucible. After fusion for 
ten to fifteen minutes the crucible, when as glowing hot 
as possible, is plunged into cold distilled water, dis- 
placing the cover of the crucible by the tongs as little as 
possible. To prevent the projeaion of any small par- 
tides of the melt, with the aid of tapping the bottom of 
the crucible and gentle pressure of the sides, the cake of 
melt is caused to fall into a large flat Berlin capsole, 
corresponding quantities of pure concentrated nitric acid 
and hot water are added, and the whole is evaporated 
down on the water-bath, continually comminnting all the 
fragments of the melt as they are gradually disintegrated 
add softened, until there remain at last more or fewer 
light-coloured flocks of silica floating in the liquid. In 
the meantime the residue of the melt, which (brms only 
a slight coating in the crucible, is placed, along with 
water and some strong nitric acid, in a boiling water-bath, 
and after a short time the solution obtained, including 
some silica, can be mixed with the chief quantity. The 
saline mass, after being sharply dried on the water-bath, 
IS again moistened with at least 20 to 25 c.c. of concen- 
trated nitric acid, and again evaporated down until as dry 
as dust. This residue when cold ii moistened with 
10 c.c. concentrated nitric acid, allowed to stand at rest 
for ten minutes, and then mixed with from 750 to 1000 c.c. 
of water, heated for fifteen minutes on the waterbath, 
and filtered from the silica, which is finally jnost carefully 
wasJied with boiling water, to which at first a little nitric 
acid is added. 

The filtrate fi-om the silica is mixed, in the cold with a 
large excess of concentrated hydrochloric acid, in order 
to separate the bulk of the lead as a chloride, which, after 
subsidence, is then filtered with luaion and washed with 
cold hydrochloric acid (i vol. concentrated acid and i vol. 
water). This filtrate it agala evaporated .to diyneis id a 



52 



Novel Reactions of Morphia. 



\ 



Aug. 2, XS^S' 



capacious capsule, especially for the complete expuliioa 
of any free nitric acid. The residue is mixed with 30 c.c. 
dilute hydrochloric acid (i : 4), and as much water heated 
on the water-bath for fifteen minutes and allowed to cool, 
when any residual traces of lead chloride are colleAed 
upon a very permeable filter, and quickly washed with 
cold water. The resulting filtrate now contains unim- 
portant quantities of lead, which are finally quantitatively 
precipitated with hydrogen sulphide. To this end the 
gas is first introduced in the cold ; it is then heated for 
«ome lime until the lead suljphide has settled, and the 
liquid is finally allowed to cool in a current of sulphuretted 
bydrogen. 

The precipitate, which is generally slight, is filtered off 
ftod washed with warm water, to which fresh sulphuretted 
bydrogen water is constantly added. Above all, care must 
be taken that the precipiution of the lead is really com- 
plete, as otherwise the further course of the analysis will 
be disturbed in the most troublesome manner, or inaccu- 
rate results will be obtained. 

Then from the filtrate Irec from lead all hydrogen sul- 
phide must be removed, by concentrating the solution 
before the iron is oxidised, by means of nitric acid or hy- 
drogen peroxide, on undertaking the general procedure for 
separating iron, alumina, manganese, lime, magnesia, 
potash, and soda. 

I have already had several analyses of rocks executed 
by a number of my pupils according to the above method, 
which agreed in their results most satisfadtorily with the 
combined results of sodium carbonate fusion and opening 
up with hydrofluoric acid. 

After further elaboration of the lead oxide method for 
the case of the simultaneous presence of titanium and 
phosphoric acid, I propose communicating all the analy- 
tical material in connexion. I cannot sufficiently extol 
the use of lead carbonate in the analysis of silicates As 
compared with the former methods, it means a very con- 
siderable economy of time, and it need fear no comparison 
with them as regards the accuracy of the results.— Z^i^ 
Anofgan, Ckitnti, viii., p. 364. 



NOVEL REACTIONS OP MORPHIA. 
By O. BRUYLANTS. 

On heating morphia or one of its salts in a steam- bath 
with a little pure concentrated sulphuric acid, and adding 
a drop of Frdhde-Buckingham reagent (x c.grm. molyb- 
date to z ex. of acid), th^re is produced a splendid green 
colour, which lasts for some time and then disappears. 

This rea^ion is almost as sensitive as the Frdhde re- 
aftioo properly so called. It seems to me to have some 
importance, because we see the same reagent produce 
two distinft reaaions with the same substance placed in 
different conditions, and also because this green coloura- 
tion is charaderistic of other alkaloids of opium. 

To produce It we heat, for two or three minutes, the 
watch-glass on which we have placed the morphia and the 
sulphuric acid, then spread out a drop of the mixture on 



a plate of white porcelain, and add a drop of the re- 
agent. 

We may combine the lilac readion of Piohde, the green 
colouration and the readion of Huseman, when operating 
on the same product. To this end we dissolve the mor- 
phia on a watch-glass in one or two drops of snlpburic 
acid. We spread out a part on the porcelain, and add to 
equal Quantity of Frdhde*s reagent, obtaining thus the 
lilac colour. Then we heat the watch-glass in the steam- 
bath, take a fresh portion of the mixture, and with a 
further quantity of the. reagent we obtain the green 
colouration. Having observed this, we introduce into the 
liquid while still green a grain of nitre, when we imme- 
diately see the green tint give place to a red colour, which 
grows paler in time, and lastly turns yellow. 

I take this opportunity to remark that it has been erro- 
neously recommended to heat the mixturo of morphia 
and sulphuric acid in the steam-bath for half an hour, to 
obtain Huseman*s reaaion ; one or two minutes will be 
sufficient. Whatever may be the purity of the acid and 
the morphia, there always is produced, after heating for 
half an hour, a violet colour more or less intenae,— a 
colouration which, in fad, has no influence upon the 
ulterior rea^ion with nitre when it Is required to identify 
pure morphia. But it is no longer the same case if the 
morphia has been extraded from some part of a dead 
body in the course of a toxicological investigation. It is 
then always more or less contaminated with foreign 
matters which sometimes colour the test-liquid in a very 
intense manner, so that it becomes very difficult to seixe 
upon the play of colours produced by the nitre. 

If we heat the produd only for one minute or two 
minutes, the mixture is very slightly coloured, and is veiy 
suitable for the readion. 

I arrange below, in a table, the colours produced bj 
morphia and some of the other bases of opium, by the 
adion of Prohde's roagent on a solution ot morphia ia 
sulphuric acid before and after being heated in the steam- 
bath, as well as the colours produced by the addition of 
nitre to the produA of the last operation. 

II. It is known that, on adding an a<)neou8 solution of 
iodic acid to a solution of morphia m sulphuric acid, 
there Is produced a deposit of iodine. On adding iodic 
acid to the sulphuric solution of morphia previously 
heated in the steam-bath, we obtain, according to thie 
proportions, a lilac which turns slowly to red and then 
disappears, or else a red at once. The former result ii 
with a trace of iodic acid, the second is with a large pro- 
portion of that reagent. This charader has some 
importance. — BuUiiin dt la Soc, Ckimiqut, Series 3, 
xiii.-xiv.. No. 9, p. 498. 



ATOMIC WEIGHTS OP NICKEL AND 

COBALT. 

By CLEMENS WINKLER. 

The author has undertaken a revision of the atoostc 
weights of nickel and cobalt, with the obje& of ascer- 
taining which of the two has the higher atomic weight. 



I. 
Fr5hde't Reaffent 
Kind of Alkaloid. on the Sulphuric bolutioo 

bifore beating. 
Morphia •« •• •• Lilac colour. 

Apomorphia •• •• Green-blue. 

Oxidomorphia •• •• Blue. 

Codeia • Dirty green, then blue. 

Narceia •• •• •• Brown, turning to green and 

then to blue. 

Narcotina Green, then greenish-brown. 

Papaveria •• «• •• Green, then blue and then 
red. 

MeconIa «• «• •• Green, very fueitive. 

Cryptopia •« «• •• Dirty green, then brownish- 
green. 



IL 

FrShde't Reagent 

00 the Sulphuric Solution 

a/Ur heating. 

Green colour. 

Do. 
Do. 
Do. 
Dirty green. 

Green. 

Green, then blue and red. 

Greenish blue. 
Dark green. 



III. 

Aa in IL, followed by the 
addition ot a grain of Nitre, j 

Green colour, changes to 
which fades and disappes 
Do. 
Violet, turning to red. 
As morphia. 
Do. 

Violet, then a fugitive red. 
Green colour, disappeara j 
once. 
Do. 
Do. 



Cmsmical IVswr» I 
Aoc. a, 1895. I 



Phenomena observed in the Precipitation oj Antimony. 



53 



The experiments were effeded by treating the meta]i 
with a solution of auro-potatsium bromide, dissolving the 
metals in hydrochloric acid, determining the hydrogen 
evolved, treatment with solution of iodine in excess, and 
titrating back the excess of iodine. 

The average of the determinations showed, for nickel, 
the value 587155 ; and for cobalt, 59'3678. 

The author thinks that these fisures roust be accepted 
as the true atomic weights of nickel and cobalt, referred 
to H=x and l^i2t'^^,^Ztit. Anorg, Chimii andCA#M. 
Ziitung, 



RECENT ANALYSES OF LEUCITE BASALT 

FROM VESUVIUS. 

By ALBERT THORPE. 

1 HAVS recently analysed samples of leacite basalt from 
Vesavitts, and the following results may be of interest to 
the reader! of the Chemical Nbws, as Vesuvius is now 
in a state of eraption. 

L IL 

Silica 47*23 4732 

Alomifia .. .. .. 18*23 18*06 

Ferric oxide .. .. 4*21 4*23 

Ferrous oxide • • .. 4*49 4*31 

M anga nous oxide •• 1*36 1*42 

Lime 8-63 8*51 

Magnesia 4*68 5*03 

Potash •• .. .. 8*00 7*92 

Soda.. • 2*63 2*70 

Titanic acid .. .. 0*23 0*36 

Phosphoric acid .. 0*31 0*20 

xoo'oo 100*00 

' The specific gravities of the basalt varied from 2*653 ^0 
2*721. 

ON CERTAIN PHENOMENA OBSERVED IN THE 

PRECIPITATION OF ANTIMONY FROM 

SOLUTIONS OF POTASSIUM ANTIMONYL 

TARTRATE.* 

By J. H. LONG. 

(Coododed from p. 45). 

Reaction with Sodium ThiosulphaU. 
Cold dilate solutions of the thiosulphate and potassium 
antimonyl tartrate can be mixed without immediate pre- 
cipitation. Application of heat, however, produces a 
light yellow precipitate, which grows deeper and finally 
b^omes bright red. This precipitate is the substance 
commonly known as antimony cinnabar, used aw a pig- 
ment, and on the large scale is made by decomposing the 
thiostilpbale by antimony chloride. In the readion be- 
tween the thioiolphate and tartar emetic the precipitate 
appears very heavy, bat the decomposition is far from 
complete, as shown by the figures given below. 

There seems to be some doubt as to the composition of 
this precipitate. Roscoe and Schorlemmer (ii., Part 2, 
324) give it as, probably, SbSaO ; referring, however, to 
other formalse. Dammer's ** Handbuch *' gives^ 

SbaOaSbaSs 
as the probable formula. Others are also given. Recently, 
Baubigny (Comptis Rendus, No. 17, 1894) has given 
reasons why the formula SbaSj should be considered the 
corred one, and the proof he presents appears to be satis- 
faAory. There remains a possibility, however, that the 
comiiosition may, under certain circumstances, vary with 
the ijiethod of preparation. In fa^, some of my own re« 



^f7 



• f Journal of the Ammcan Chemical Society^ vol. xvii., No. a. 



i 



suits seem to show this, and I am now engaged in stady« 
ing the question further. But, as made in the reaAion in 
hand, the composition seems to be 2SbsS3.HaO. This 
was determined by the following considerations :— The 
precipitate dissolves in hydrochloric acid withoat libera- 
tion of sulphur, yielding a perfe^ly clear solution. A so* 
lution made in this way was heated, mixed with a little 
tartaric acid solution, and precipitated by hydrogen sul- 
phide in the usual manner. On filtering oflf the orange- 
yellow precipitate so obtained in a Goodi crucible, drjring 
at i2o^ and weighing, the weight was always found less 
than that of the antimony cinnabar taken. 

Sulphur determinations were made by dissolving a grm. 
or less of the substance in strong S-free solution of potas- 
sium hjrdroxide, and then oxidising the sulpho-talt 
formed by washeid chlorine gas (method of Rivot). The 
results of these tests were as foUows : — 



Calculated for sSbaSrHtO. 

Sb 69*56 

S 2783 



Foend. 
€9-80 
ayya 



No determination of the water was made, but its pre- 
sence was shown in the substance dried at X20° by heat*, 
ing to a higher temperature in a narrow glass tube. 

In a series of experiments on the precipitation a 
number of portions of the tartrate, of 5 grms. each, were 
weighed out and dissolved in 150 c.c. of water. Varying 
amounts of the thiosulphate in 50 c.c. of water were 
added, and then water enough to make exadly 250 c.c. 
The flasks holding the mixtures were closed with per- 
forated stoppers containing long glass tubes, and then 
heated in the water-bath one hour. In this way evapora- 
tion was pradically avoided. At the end of the hour the 
precipitates were colleded on a Gooch funnel, dried at 
120^ and weighed with the following results : — 



No. of 
eiperimeot. 


Weight of 

ira,S,0.5H«0 added. 

Gmu. 


WelRhtof 
Grm. 


z. 
2. 


0*1 
0*2 


0*0039 
0*0068 


3. 


0-4 


0*011 X 


4- 


08 


0*0x78 

0*2XZ2 
04809 


1: 

I: 


2-6 
3-2 

12*8 



In a second set of tests I dissolved, in each case, zo 
grms. of the tartar emetic in 100 cc of hot water and 
added the thiosulphate in 50 cc of hot water. The 
mixtures were kept at xoo^ two hours and then filtered. 
Results as follows : — 



No. of 
experimtat. 

9- 
10. 
XT. 
12. 



Weight of 
Na,S,0,.5H.O added. 



5 

zo 

20 



Weieht o£ 
precipiute. 

0-I9I5 
0*4041 
0*5162 
0*68x8 



It IS evident from these figures that in both sets of ex* 
periments the readion is far from complete and not easily 
determined. It is, perhaps, quite comijlex. I noticed in 
no case the escape of hydrogen sulphide or sulphurous 
oxide, and the gradual change in colour during precipita- 
tion from very light yellow to bright red suggests that it 
takes place in two stages. Vortmann {Bir. d. Ch$m. 
Ois,t xxii., 2307) has studied the general problem of de- 
composition of thiosulphuric acid, and states that it 
breaks up into HaS, O, and SOa* In presence of certain 
metals, tetra- and pentathionates seem to be formed. It 
is certain that no sulphate is formed in the readion in 
hand, but the proof of formation of the several thionic 
acids is difficult because of the incompleteness of the re- 
adion and the presence of the great excess of thiosul- 



Phenomena observed in the Precipitation of Antimony. 



J4 

pbate. In cases of complete readion , however, Vortroann 
and Vaobel, also (Btr. d, Ckem, Gis., xxii., 2703), have 
shown that these acids are formed. 

I suggest, therefore, this explanation of the present re- 
aAion. At the outset there may he, as with borax, a de- 
composition according to this equation — 

2KSbOC4H406+ Na2Sa03+ H2O » 

«= Sba03+aKNaC4H406+ HaSaOs 
then— 

Sb203+2HaSa03«SbaS3+aHaO+SOa+05, 

the oxygen and sulphur dioxide being held, however, to 
form polythionates. 

The gradual change of colour can be accounted for by 
the gradual change of oxide into sulphide of antimony, 
and it seems possible that under certain conditions of 
concentration and temperature a part of the oxide should 
remain unchanged, accounting for the results of some of 
the analysts who have examined the precipitate. In 
several instances I modified the experiment by mixing 
warm solutions of the tartar emetic with warm thiosul- 
phate solutions, and then throwing the mixture into a 
large volume of cold water the instant a precipitate began 
to fqrm, to check the reaaion. The precipitate which 
now settled was very light coloured instead of red, and 
appeared to be a mixture of oxide and sulphide. The 
microscopic appearance of this precipitate is distindly 
difierent from that of the antimony cinnabar. 

As explained at the outset, some time elapses after 
mixing cold solutions before a precipitate appears. In 
the beginning of the interval the solution may be so clear 
that accurate polarimetric observations are possible. But, 
contrary to expedations, based on the behaviour in other 
cases recorded, I find the specific rotation of the tartar 
emetic, in this stage of the readion, quite unchanged. 
After precipitation a marked decrease was observed as 
usual. This is shown in the following table in which the 
filtrates from the last precipitates referred to were made 
made up to 250 c.c. before polarisation : — 



r CBsMieAt. Ntvs, 
\ Aug. a, 1895. 



ETo.of 


TbiosDiphate 
added. 


ao 


ao 


erimeot. 


olMerved. 


ciIculAted 




Grint. 






9- 


5 


I0-90*' 


1089^ 


10. 


10 


10-43° 


10-46'' 


11. 


15 


10*07** 


10-24° 


12. 


20 


969° 


9-93'' 



In the last column the rotations were calculated on the 
assumption that antimony is precipitated and Rochelle 
salt formed according to the last eouations. In the 
eleventh and twelfth experiments the thiosulphate is pre- 
sent in amount much in excess of that necessary to com- 
plete precipitation by these readions, and it is evident 
that a decomposition of the adive molecule has taken 
place not indicated by the amount of precipitate. 

There seems to be a fundamental difference between 
the readion with the thiosulphate on the one hand, and 
those with the borate, carbonate, phosphate, acetate, and 
tungstate on the other. In the first case we appear to 
have no breaking up of the complex tartrate until adual 
precipitation occurs, while in the others the stages are 
quite distindl. I have shown that in these last readtions 
acids are liberated which may be readily recognised. It 
is also true that these acids are pradlically without adion 
on antimonouB oxide, from which it would follow that this 
substance might remain a long time, possibly in the hy- 
drated form, in contadt with the liberated acids without 
change. This would not be the case with liberated thio- 
sulphuric acid. If set free in the presence of antimonous 
oxide, even the dry precipitate, it soon converts it into 
sulphide. Any cause, therefore, which ads to destroy the 
equilibrium in the solution of tartrate and thiosulphate 
must lead to the almost immediate formation of a pre* 
cipitate. 

In many of our most familiar cases of precipitation the 
foimation of the precipitate is so rapid that we are accus- 



tomed to look upon it as instantaneous. But by varjring 
the conditions of precipitation it may be shown that even 
the readion between barium chloride and sulphuric acid 
is one which consumes an appreciable interval. In such 
cases, however, we have no means of knowing what takes 
place before the precipitate becomes adually visible. It is, 
doubtless, true that the liquid regarded as supersaturated 
for BaS04 does not begin to throw this out in solid form 
until a relatively large number of these molecules com- 
bine to produce a particle of a certain size, but at what 
rate the Ba and SO4 ions combine cannot be shown. 

But in the cases before us we have evidence, first, of 
the gradual breaking up of the complex potassium anti- 
monyl tartrate, and then, also, that a relatively large 
amount of the antimony may be separated before any of 
it falls as a precipitate. The stage of precipiution seems 
to follow as a perfedly distinA and also progressive one. 
It is hastened, as in other cases of supersaturation, by 
heat or agitation. One of the reaAions shows, also, that 
a relatively long time is consumed in combination as well 
as in dissociation. In the case of the mixture containing 
the tartrate and tungstate we have evidence of the splitting 
of the first molecule, and then, from the slowly increasing 
rotation, evidence of the addition of an element from the 
second to the adive part of the first. Both of these 
phenomena are observed before precipitation appears. 

It must be remembered that the several acids shown to 
be liberated in these experiments are all so-called weak 
acids, or acids but slightly dissociated in solutions. It 
is also true, as a test of their eledric condudiyities 
shows, that the solutions of tartar emetic are relatively 
little dissociated (see in this coonedion Hugo Haedrich, 
Ziit, Phys. Chem,, xii., 496). There is doubtless, there- 
fore, a close connedion between the phenomena Outlined 
above, and others depending on the degree of dissociation 
of the ions in solution. A study of the behaviour of 
weaker solutions would doubtless lead to interesting re- 
sults not brought out in the above experiments which 
were undertaken mainly to show the charader and amount 
of precipitates formed. A discussion of the behaviour of 
dilute solutions will follow. 



A REVISION OF THE ATOMIC WEIGHT OF 

STRONTIUM. 

First Paper : The Analysis of Strontic Bromidb.* 

By THEODORE WILLIAM RICHARDS. 
(Continued from p. 43). 

Thi Rnfio of SUver to Strontic Bromidg. 
First Stfri#5. —In this series a slight excess of silver was 
taken, dissolved, and diluted with at least a hundred 
times its weight of water, and added to the strontic bro- 
mide in glass-stoppered flask. After the usual long-con- 
tinned shaking, the precipitate was coUeded upon a 
Gooch crucible, and the excess of silver in the evaporated 
filtrate and first five or six wash waters was determined 
after Volhard's method {Proc. Amtr. Acad., xaria., 66), 
Upon sobtrading this small excess of stiver from the total, 
the amount corresponding to the strontic bromide re- 
mains. This method is not a very satisfadory one, 
final result being probably too low, because of loss 
portion of the slight excess of silver. 

Second S/n>i.— Here the end point of the readion 
determined by titration after the method of Abral 
{Proc. Amir. Acad., xxviii., 24), very weak solution 
silver and hydrobromic acid being used to titrate b 
wards and forwards. The mean reading was taken in t 
case, and the method of procedure resembled exadly 
work with barium. These results are much more 



♦ Contributions from ihe Chemical Laboratory of Harvard 
lege. From the ProteaUkgi of the Amtricau Acaitmy. 



1 ■•■icAi. MBwm, 1 



Aof. a, 1895. 



Revmon of the Atomic Weight of Strontium. 



worthy tfaas the last. la tevenl cases the sample of 
Btrontic bromide was first analysed by this method, and 
•nbseqnently an excess ol silver nitrate was added and 
the preceding method was applied. 

Third S$rus. — For this series a new method was de- 
vised. According to Stas [Mim, de PAcad, Belg., xliii.. 
Part ii., Introdadion), argentic bromide is wholly insoluble 
in water; according to Goodwin {Ztit.f. Phys, Chem., 
ziti.,645), it is only yery slightly soluble ; while according 
to Kohlraosch and Rose {Ztit.f. Pkys. Chim,, xii., 234), 
it is solaUe to the extent of three-tenths of a milligramme 
in a litre. The time doring which chloride of silver 
is shaken makes an enormons difference in the solubility, 
and it is not impossible that a similar effed may occur 
here. Perhaps Kohlrausch and Rose did not agitate their 
prodpiute so thoroughly as Stas did. According to the 
present experience the purest silver bromide was capable 
•f yielduig a filtrate which would give a very faint opales- 
coDOe with both silver and hydrobromic acid ; and this 
tOtA usuallv diminished upon long continued agitation. 
The method of determination used in this series was based 
upon this fad. Somewhat less silver than the amount 




Fig. 3. 

required was added to the Btrontic bromide, and a very 
weak standard solution of argentic nitrate (the cubic 
centimetre contained a milligramme of silver) was dropped 
in until equivalent solutions of silver and hydrobromic 
acid produced equal opalescence in two similar pipetted 
portions of the supernatant liquid. Since the opalescence 
was so faint that one could only with difiiculty see it at 
all oader ordinary conditions, a piece of apparatus which 
may be named a ** nephelometer " (vi^ifi a cloud), was 
devised for deteding it. Two test- tubes, holding each 
just JO C.C., were arranged in a wooden frame so that 
a centims. of the top of the tubes were in darkness. The 
bottoms of the tubes were fitted into the top of larger 

3>aque tubes containing water, and were provided with 
osely fitting cylindrical shades, which could be raised or 
towered independently over a graduated scale. All these 
contrivances prevented disturbing side refledions from the 
meniscus at the top of the tube and the rounded glass at 
^wtho bottom. The two test-tubes were slightly inclined 
Itowards one another, so that the eye at a distance of 8 
■nches could look diredly into both without change of 
X>osition. Filled with pure water the tubes appear abso- 
llutely blacky even when exposed to a strong light ; but an 



55 

absurdly small amount of precipitate, which no ordinary 
means could discover at all, makes a very evidoot doadt* 
ness. By sliding the shades up and down a point may bo 
found where the two tubes, containing solutions of dif* 
ferent cloudiness, appear equal in depth of tone. The 
reason of this is that only the portion of the opalescence 
is visible upon which light is allowed to fall. Of course the 
intensities of the opalescence, and hence the quantities of 
precipitate, are then inversely as the length of the lighted 
portions of the two tubes. 

If care is taken to dired the light horisontally upon the 
tubes, considerable accuracy may be obtained with the 
apparatus, especially if tlie columns are neariy equal in 
cloudiness. 

A pointed blackened roof with a small hole in the top 
for the e3re is useful in excluding light from the surface of 
the liquid, thus rendering the comparison easier. The 
chief advantages in the apparatus lie in the fads that the 
two disks of light to be compared remain equal in sixe 
throughout the comparison, and that the eye is not con* 
fused by bright surface refledions. Two typical test series 
are given below. In each case one shade was adjusted at 
10 centims. and the other was run backward and forward 
until apparent similarity was obtained. 

{a). One tube contained o'oio m.grm. of silver, and the 
other 0*0x25 m.grm., measured by means of a very dilute 
standard solution. Both amounts were made up to 25 cCy 
and I c.c of hundredth normal hydrochloric add was 
added to each. The opiUescence in each was then com- 
pared after a thorough stirring and a short delay. 

H tights ofColumiu afpiering AUhi* 

Stronger Solutioo. Weaker Solotion. 

da. Cm. 

87 lO-O 

7 "9 lo'o 

6*9 xo-o 

7*6 xo*o 

8*4 xo^o 

8-6 xo-o 

8-9 xo*o 

Found .. 8*1 xo'o 

True value 8*0 xo*o 

(6). In a similar experiment one tube cootil«ed 0*025 
m.grm. of silver, the other 0*0225 m.grm. 

H tights of ColufHHS apptoHng Alikt. 

Strooger Solatioo. Weaker Sdation. 

Cm. Cm. 

8'8 XO'O 

8-9 xo-o 

8*2 X0*0 

9*5 XO'O 

8*9 XO'O 

8*7 XO'O 

8*9 xo*o 

9*4 XO'O 

Found •• 8*9 XO'O 

True value 9*0 xo*o 

Some series were more accurate, others less so, than 
these, which serve to give a fair idea of the probable error 
of the method. 

The details of the analysis must be evident from what 
has been said. The method is similar to Stas's third 
method for the determination of chlorine (Proc, Amtr, 
Acad,t xxix., 86), except that of course the opalesceoce is 
very much fainter. 

Below are given the tables containing the data and 
results of the threp series ; these will be comprehensible 
without further remark. 



1 



56 



Revision of the Atomic Weight of Strontium. 



« CBIMICAL NBA 

1 Aug, a. X895. 







Ratio of Strontic Bromide to Silver. 

First Series. Volhard's Method. 

Weight Total Weight of Ratio 

of Weieht ExceM Silver 
Strontic ot of corret. to SrBr, 




&o. 


No. 


Atomic 


of 


of 


Weight 




Bromide Silver Silver. Strontic 


Sr. 






taken. uken. Bromide. Ag.. 








Grma. M.g. 




X. 


III. 


1*49962 1*30893 1-38 1-30755 II4'689 


87658 


2. 


HI. 


2-4x225 2 10494 1-43 210351 1x4-677 


87633 


3- 


111. 


2-56153 2*23529 1*72 2*23357 114*683 


87*645 


4- 


V. 


6*15663 5*3686 0-2 5*3684 114*683 


87*644 



12*63003 



xx*oi303 X 14*683 87*644 



Ratio of Strontic Bromide to Silver, 
Second Series. Abrahall's Method. 



No. 

of 

Anid. 


No. 

of 

Spec 


weight 

Strontic 

Bromide 

taken. 


Weight 

Silver 
required. 


Ratio 

SrBr, 
Ag. 


At. wt. 

of 

Strontium. 


1: 

.7- 
8. 


III. 

III. 

III. 

V. 


Grms. 
X*49963 
2*41225 


Grma. 
X*30762 
2*10322 


X 14-683 
X 14-693 

114-694 
114*691 


87645 
87*667 
87668 
87663 






15'3X577 


13-35386 


XX4*692 


87-663 






Third Series. New Method. 




9. 
xo. 

XX. 
X2. 


IV. 
VI. 
VL 
III. 


2*9172 
3-8946 
4-5426 
5-2473 


2-5434 
3-3957 
39607 

4-5750 


114*697 
XI4-692 
XX4-692 
1x4-695 


87-675 
87665 
87-664 
87*671 






x6'6oi7 


14-4748 


114-694 


87*668 






(To be cootinaed.) 







PROCEEDINGS OF SOCIETIES. 

CHEMICAL SOCIETY. 
Ordinary Meetings jfune 20th 1 1895. 

Mr. A. O. Vbrnon Harcourt, President, in the Chair. 

(Concluded from p. 48). 
02. **^n some Physical Properties of the Chlorides of 
Gold:' By T. K. Kobe, D.Sc, A.R.S.M. 

The roelting-f>oint of trichloride of gold is found to be 
288° C, under a pressure of about two atmospheres of 
chlorine. Its density is 4*3, and that of the monochloride, 
7*4. These determinations tend to show that the atomic 
volume of chlorine when in combination with gold is 
4X5*x, instead of 3x5*1, the volume assigned to it by 
Schrdder in the case of some of its other compounds. 
Mr. W. J. Pope found that volatilised crystals of tri* 
chloride of gold are crystalline aggregates, but that they 
cannot be referred to any system as they do not transmit 
the light from a sodium flame. 

93. *• The Dissociation oj Liquid Nitrogen Peroxide. 
Part II. The Influence of the Solvent:' By J. Tudor 

CUNDAI^L. 

The author measures colorimetrically the dissociation 
at different temperatures of solutions of nitrogen peroxide 
in fourteen " indifferent '' solvents, viz. :— Chloroform, 
ethylene chloride, ethylidene chloride, methylene chloride, 
carbon tetrachloride, benzene, monochlorobenzene, mono- 
bromobenzene, ethyl bromide, ethylene bromide, bromo- 
form, silicon tetrachloride, carbon disulphide, and acetic 
acid. He finds that the dissociation takes place in the 
same way, though to a different extent, in the various sol- 
vents ; the extent of dissociation at any temperature 



being in the main an additive property, though probably 
modified by constitution. Thus the carbon atoms in a 
compound have very little influence on the dissociation 
power ; those of hydrogen have more ; then those of bro- 
mine and chlorine, whilst those of sulphur and silicon 
have most. Ethylene chloride is not so effeAive at 
ethylidene chloride. 

The author compares his results with those^ 
Mentschutkin {Zeit, Phys, Chem,, i., 61 x, and } 
brings evidence to show that, if the heat oflltssociatton 
of liquid nitrogen peroxide is the same as that calculated 
by van't Hofffor the gas, any read ion that may take 
place between the dissolved substance and ** indifferent *' 
solvent is probably not exothermic. 

94. **Condensation of Ben»il with EthyUc AcetoacetaU:* 
By Francis K. Japp, F.R.S., and Q. Drucb Lamdxr, 
B.Sc. 

By heating a mixture of benzil and ethylic acetoacetate 
with sodium ethoxide in alcoholic solution, the two first- 
mentioned compounds condense according to the equa- 
tion 2Cx4HioOa-f C6Hio03=rC34H2806+H20. This con. 
densation produdt is obtained as a sodium compound con- 
taining alcohol of crystallisation : C34H27Na06,CiH60. 
Acetic acid liberates from this compound ethylic anhydro* 
dibenjuilacetoacetatet C34H28O6, which crystallises from 
alcohol or from a mixture of ethylic acetate and light 
petroleum in flat needles or prisms, with bevelled edges, 
melting with decomposition at 2xo~2XX^ Although this 
compound contains the carbethoxyl group, it was not 
found possible to hydrolyse it to the corresponding acid, 
owing to the ease with which it is decomposed with re- 
generation of benzil. 

By boiling this compound with alcohol containing a 
little sulphuric acid ethylic ethylanhydrodibenMilaceio* 
acetate, C34H37(C2H5)06, was obtained, which was de- 
posited from alcohol in slender prisms melting at X97*. 
It was readily hydrolysed by caustic potash. Ethyl' 
anhydrodihentylacetoacetic acid, C32H2s(C2H5)06, is de- 
posited from benzene in microscopic matted needles 
melting at 2x6^ It is isomeric with the condensation 
compound. 

Substituting isobutylic for ethylic alcohol in the fore- 
going etherification, ethylic isobutylanhydrodibenMilacetc- 
acetate, C34Ha7(CiH9)06, was obtained. It crystallised 
from a mixture of benzene and light petroleum in minute 
needles, melting at 202^ On hydrolysis it yielded iio- 
butylanhydrodibenxilacetoacetic acid, C3aHa^(C4H9)06t 
which was deposited from a benzene solution m slender 
needles melting at 237''. 

When the condensation compound was oxidised with 
chromium trioxide in acetic acid solution it yielded a 
monobasic acid, C2aHi604, which crystallised from a 
mixture of ethylic acetate and light petroleum in needles 
melting at 200** with evolution of carbon dioxide. In this 
process of decomposition by heat the acid is converted 
into a compound CaxHxeOi, which is deposited from 
alcohol in needles melting at 1x9— xao**. The constitu- 
tion of these two compounds may possibly be expressed 
by the formulae — 



C6H5CO 

CeHc-C-COOH 

I 
C6H5CO 

Phenyldibenioylacettc acid. 

Fuming hydriodic acid at 
condensation produd into 



and 



C6H5-CO 
C6H5-CH 



M 



C6H5CO 

Phenjldibenxoyloiethaoe* 

ts boiling-point converts t^e 
compound C3XH24O, which 
crystallises from a mixture of ethylic acetate and ligbt 
petroleum in short prisms melting at X87 — xgB^'T— "■ *7 

C34Ha80fl+3Ht-C3,H240 + CaH60+COj+2HaO. V 

Suspeding that the condensation produA was a carb^ 

ethoxyl derivative of anhydracetonedibenzil (Japp an^ 

Miller, Tram., 1885, xlvii., 34), the authors reduced th^ 

latter compound with boiling hydriodic acid, and obtainej** 



■^ 



I 



t 



Colouring and other Constituents contained in Chay Root. 



ft c»^ 



Cbmiical Niwa* i 
Attf. it iS^s. f 

tbe foiegoiog redudion compound CjiHa40 (m. p. 187 — 
i8ft^ together with an itomeride crystallising from a 
mixture of ethylic acetate and light petroleam in pyramids 
melting at X55--i59°. 

The restUts do not permit of a conclusion being drawn 
aa to the constitution of the condensation prodoA. The 
constitution of anhydracetonedibenzil is also unknown. 

95. ** On a Method for Preparing tki Formyl Diriva- 
Uvet of tht Aronatic Amines,** By H. R. Hirst and 
J. B. CoHBN, Ph.D. 

Formamide rea^ with the aromatic primary amines in 
presence of cold glacial acetic acid, forming formyl de- 
rtvatives. The mixture is allowed to stand for a few 
boars, and the produd poured into water. The resulting 
derivative is nearly pure, and the yield is very satisfadory. 
The readion takes place according to the equation — 
R'NH + HCONHa+CH.COaH- 

- R'NHCOH + CH3COaNH4. 

The secondary aromatic amines containing an alkyl 
radicle only read on heating, whereas the tertiary amines 
and diphenylamine do not read even after continued 
boiling. 

The formyl derivatives of the following bases have been 
prepared : — Aniline, ortho- and para-toluidine, a- and ^- 
oaphthylamine, phenyl- and orthotolyl-hydrasin, methyl- 
and ethyl-aoiline, paraphenylenediamine, and bensidine. 

96. 'M Modification of Zincke*s Reaction.*' By H. R. 
Hirst and J. B. Cohrn, Ph.D. 

A small piece of aluminium foil coated with mercury, 
which is prepared by dipping the foil into a solution of mer- 
curic chloride, is capable of bringing about a readion be- 
tween beoayl chloride, chloroform, &c., on the one hand, 
and aromatic hydrocarbons on the other. This readion 
closely resembles that of Ziocke, but takes place at the 
ordioarr temperature. With bensyl chloride and benseoe 
m satisfadory yield of pure diphenylmethane may be ob- 
tained. In a similar manner phenyl tolyl methane and 
pbeoylxylylmethane have been prepared. 

• 97. ''i4 Method for Preparing Cyanuric Acid,** By 
W. H. Archdeacon, B.Sc., and J. B. Cohbn, Ph D. 

When area in fine powder is heated in a sealed tube 
whh the calculated quantity of phosgene in 20 per cent 
toluene solution, little adion occurs until the temperature 
rises above iSo*'. A tube which had been heated for four 
boura at 170*180° showed very little pressure on 
opening ; but after being re-sealed and heated for seven 
boars at 190° and eight and a half hours at 230^ great 
pressure was observed on opening the tube, and hydro- 
chloric acid fumes were copiously evolve J. The brownish 
microcrystalliae produd was separated by filtration and 
dried tn vacuo* It amounted in two experiments to 133 
and 127 per cent of the urea used. It dissolved without 
change in cold concentrated sulphuric acid, being re-pre- 
cipitated in a crystalline form by water. It dissolved also 
in alkalis, and from the neutral solution in ammonia silver 
nitrate threw down a white amorphous precipitate. 

Tbe cbaraderistic needles of the sodium salt, and the 
araethyat-coloured precipiute with copper ammonium 
solphate solution, served to identify the compound as 
cyannric acid. 

Tbe crude prodod gave the following result on analy- 
sis:* 
I« 0*095 grm. gave 28*2 c.c nitrogen at 17^ and 737 m.m. 
IL o' 1753 grro. gave 0*040 grm. Had and 0*179 grm. of COa. 
Tb«oryfor(CONH).. Foond. 

C •• •• •• 27*91 27*85 

H 2*33 a-53 

N ^256 33*38 

The readion probably occurs according to the equation 
5CO(NHa)a+3COCla-3(CONH)s+6HCl. 

98. *' The OximeiofBenMldehydand their Derivatives,** 
By C M. LuxMOORi, B.Sc. 
Tbe paper contains an account of experiments tinder- 



57_ 

taken with a view to throwing further light on the iso- 
merism of the aromatic aldoximes. As already mentioned 
in a preliminary note by Professor Dunstan and the 
author (Proc, Chem, Soc, 1893, 253), in exaniniag tb« 
mechanism of the change of benxantialdoxime into 
beossynaldoxime by hydrogen chloride, the previoasly 
unknown bensantialdoxime nydrochloride has been iso- 
lated; on solution it is converted into the Sjm-bydro- 
chloride. The two isomeric sulphates have also been pre- 
pared. Since the change of the antiosime into its iso- 
me ride is always preceded by the formation of a deriva- 
tive of the former, which then passes into the more staUe 
syn-derivative, a stereo-chemical explanation of the iso- 
merism is rendered probable. 

Bv the adion of methyl bromide on bensantialdoxime 
the hvdrobromide of its ** nitrogen ** methyl ether is pro* 
duced (m. p. 67"). This ether yields the same produds 
of hydrolysis and redudion as the " nitronn '* methyl 
ether obtained from benssynaldoxime. It diners from tbe 
latter in its lower melting-point and in tbe extreme readi 
nesB with which it is hydrolysed. The hydrobromide is 
stable, but the ether itself rapidly pssses on standing into 
the isomeric syn- nitrogen ether. Strndoral formula are 
insuflficient to explain the existence of the four isomeric 
ethers (two ** oxvgen " and two ** nitrogen ") which are 
known. Probably, therefore, the aldoximes themselves 
are stereo-isomeric ; but both ad tautomerically, and the 
synaldoxime reads more readilv in the sense of tbe 
isoximido formula than the antialdoxime does. 

Treated with phosphorus pentacbloride both oximes 
yield a little formanilide, but chiefly bensonitrile. Phos- 
phorus trichloride converts bensantialdoxime into an ex- 
tremely unstable chlorine derivative; with benssyn- 
aldoxime it yields benxonitrile and hydrogen cblonds 
instantaneously. 

Almost all the stereo-chemical hypotheses equally wdl 
explain the isomerism of oximido-compounds of triad 
nitrogen ; but in the case of derivatives with pentad nitro- 
gen Pickering's theory is more in accordance with tbe 
fads than any other. 

99. **Ona Cotouring-matterfrom * LomoHa itici/olia * 
and *Lomatia longifolia,' ** By Edward H. RBNMn, 
M.A. (Sydney), D.Sc. (Lond.). 

The author describes a yellow colotiring-matter adhering 
to the seeds of two different species of Lomaiia, a plant 
belonging to the order Proteacese. The colouring-matter 
is easily extraded by hot water, and is rsgarded by tbo 
author as hydroxylapachol. Its barium denvative closely 
resembles the barium derivative of hvdroxyhydrolanacbol 
described b^ Hooker. When treated with sulphuric acid 
under certam conditions, it is converted into hydroxy 'fi* 
lapachone. Other derivatives are described in the paper, 
and also an isomeric hydroxylapachoU 

loa " The Colouring and other Constituents contained 
in Chay Root,** Part II. By A. Q. Pbrkin and I. I, 
Hummel. ^ ^ 

A previous examination of chay root {Trans, Chem. 
Soc, 1893, 1160) showed that it contained robicbloric 
acid, two waxes, cane-sugar, ruberytbric acid, alisarine, 
two dimethyl ethers of antbragallol (A) and (B), m. p. 
209% and 225—227^ ; an alisarine monometbyl ether, and 
M-bydroxyanthraquinone. By the investigation of very 
large quantities of the root, a cwts«, obtained tbroogb 
the Imperial Institute, two new snbstances have been 
isolated. 

One substance, CX5H10O4, was obtained as orange- 
coloured needles melting at 232^ When heated witb 
hydrochloric acid to 180* it yielded hystasarin, and waa 
found to contain one methoxyl group. It is tbertlore an 
hystoMarinmonomcthyl ether, — 
CO ^ 

OCH5 
OH- 




58 



'Six Dichloro toluenes and their Sulphonic Acids. 



I CHSlflCAL NbWS, 

1 Aue a,!i8g5. 



A second constituent, CX6H13O5, formed minute oraoge- 
red needles melting at 2x2—2x3% and its acetyl compound 
at x6o°. It contained two metboxy groups, and by the 
adion of hydrochloric acid at z8o^ was converted into 
anthragallol. It was consequently an anthragallol dime- 
thyl ether, and it is interesting to note that chay root 
therefore contains the three dimethyl ethers of anthra- 
gallol. 

Since the publication of the previous communication 
{loc, cU,)t Schunclc and Marchlewski {Trans. Chem, Soc, 
1894, 1S2) b^vc prepared the alizarine /Smonomethyl ether 
from alizarine. This is not identical with that found in 
ehay root, which must consequently be the a-compound, 

CO OCH3 



UJJ 



OH 



CO 

The readiness with which this is decomposed into aliza- 
rine by boiling with dilute alkalis, readily accounts for its 
non-produdion by the usual methods. 

xoi. '* Thi Six Dichlorotolutnti and thtir Sulphonic 
Acids,^* By W. P. Wynne and A. Oreeves, Assoc. 
R.C.S. 

Sulphonic derivatives of the i : 2: 5- and i : 3 : 4 di- 
chlorotoluenes were described in a previous paper {Trans, 
Chim* Soc, 1892, 1050, it seqJ) ; the present communica- 
tion deals with the remaining isomerides and their 
sulphonic acids. 

1:2: yDicklorqtoluen* was prepared by three methods : 
{a) from 1:2: 5-nitrorthotoluidine by chlorination, (6) 
from Lellman and Wurthner*s x : 2 : 3-nitracetortho- 
toluidide (m. p. 158°, cf, Annaltn, ccxxviii., 239), and {c) 
from orthochlorotoluenesulphonic acid by nitration. It 
boils at 207—208° under 760 m.m. pressure, and on oxida- 
tion yields a dichlorobenzoic acid melting at 164" {cf, 
Seelig, Annaltn, ccxxxvii., 162). On sulphonation two 
isomeric acids are obtained, which can be separated by 
means of their barium salts. The acid from the less 
soluble barium salt forms a very soluble chloridi, crystal- 
lising in radiate needles, melting at 45% and an amidet 
melting at 221% whilst that from the more soluble barium 
salt is the 1:2:3: 5-derivative, and like this yields a 
chloride, crystalli'sing in well-defined prisms, melting at 
85^ and an amide, melting at 183*. 

X : 2 : 4'DichlorotolueHi was prepared (a) from meta* 
tolylenediamine by Erdmann*s method (B^rnxxiv., 2769), 
{b) from 1:2: 4-nitrorthotoluidine, and (c) from ortho- 
chlorotoluenesulphonic acid by nitration. It boils at 
199 — 200* under 760 m.m. pressure. On sulphonation, it 
yields the x : 2 : 4 : 5>acid, charaderised by the chloride 
crystallising in elongated scales, melting at 71°, and the 
amide, melting at 177". 

1:2: 6-Dichlorotoluene was prepared from the 1:2:6- 
nitrorthotoluidine of Green and Lawson {Trans, Chem, 
Soc, 1891, 10x3). It boils at 199— 200* under 760 m.m. 
pressure, and on oxidaHon yields a dichlorobenzoic acid 
melting at 139^ {cf, Claus and Stavenhagen, Annalen, 
cclxix., 228). On sulphonation, an acid is obtained which 
gives a fA/orii#, crystallising in piismatic needles, melting 
at 6o% and an amide, melting at 204*. 

1:3: S'Dichlorotoluene was prepared from the x : 3 : 4 : 5- 
dichloroparatoluidine by Lellmann and KIotz*s method 
{Annalen, ccxxxi., 321) and from the i : 2 : 3 : 5 dichlor- 
orthotoluidine of Claus and Stapelberg {Annalen, cdxxiv., 
292). It boils at 201 — 202" under 760 m.m. pressure. On 
sulphonation, an acid is obtained which forms a very 
soluble chloride, melting at 45**, and an amide, melting 
at 168°. 

To aid in the determination of the constitution of the 
dichlorotoluenesulphonic acids, the nitro-derivatives of 
the five known chlorotoluenesulphonic acids have been 
prepared and examined. For example, 1:2: 4 ortho- 
chlorotoluenesulphonic acid on nitration gives as chief 



produd the 1:2:4: 5-nitro-acid, since the dichloro* 
toluenesulphonic acid obtained from it is identical with 
that obtained from 1:2: 5-dichlorotoluene {Trans. Chem, 
Soc, 1892, 1052). In like manner, 1:2: 5-orthochloro- 
toluenesulphonic acid is shown to give as chief produd 
the 1:2:4: 5-nitro-acid, and as subsidiary produd the 
1:2:3:5 nitro*acid. 

1:2: 3-Nitrorthotoluidine is converted by Sandmeyer*s 
method into the nitrorthochlorotoluene, which boils at 263" 
under 760 m.m. pressure. On redudion, this yields the 
1:2: i-orthochlorometatolutdine, which boils at 228—229" 
under 760 m.m. pressure, and forms an acetyl derivative 
melting at 132^ 

1:2: 4-Nitrorthotoluidine in like manner yields the 
nitrorthochlorotoluene, which crystallises in pale yellow 
needles, melting at 65°, and the orthochloroparatoluidinct 
which boils at 245^ under 760 m.m. pressure, and forms 
an acetyl derivative melting at 86% 

X : 2 : 5- Nitrorthotoluidine on chlorination in the pre- 
sence of iodine yields a chloronitrorthotoluiJine melting 
at i68% This is the 1:2:3: 5-derivative, since, by eli- 
minating the NHa-radicle, it forms the i:3:5-nitro« 
chlorotoluene melting at 61°, the x : 3 : 5-chlorometa- 
toluidine, charaderised by its acetyl derivative melting at 
151° {cf. Honig, Ber., xx., 24x9), and 1:3: 5-dichloro* 
benzoic acid melting at x82% By Sandmeyer's method 
the corresponding nitrodichlorotoluene, which ciystallises 
in pale yellow needles melting at 83^, was obtained, and 
from this, by redudion, the dichlorometatolmdinc, which 
crystallises in needles, melts at 88^, boils at 292° under 
760 m.m. pressure, and forms an acetyl derivative melting 
at 187°. 

1:2: e.Nitrorthotoluidine yields a chlororthotoluidine, 
which boils at 245"^ under 760 m.m. pressure, and forms an 
acetyl derivative melting at 154% 

The mixture of dichlorotoluenes obtained b^ chlori- 
nating orthochlorotoluene under Seelig*s conditions {loc, 
cit.) is being examined with the objed of determining 
its constituents. 

X02. '* The DiiuUhonic Acids of Taluem attd ofOrtkO' 
and Parachloro'toluene," By W. P. Wynne aod J. 
Bruce. Assoc. R.C.S. 

As is known {cf. Trans, Chem* Soc,, 1892, X082), para* 
chlorotoluene, on sulphonation, forms a produd containing 
both the X : 2 : 4- and 1:3: 4-sulphonic acids. Experi- 
ments have been undertaken with the objed of estimating 
the relative proportions of these acids, both diredly and 
by an examination of the disulphonic acids obtained by 
sulphonating parachlorotoluene with 20 per cent anhydro- 
sulphuric acid. For the purposes of comparison, chloro* 
acids have been prepared by Sandmeyer's method from 
the paratoluidinemono- and di-solphonic acids of known 
constitution. 

The paratoluidinedisulphonic acids obtained by Richter 
from the x : 3 : 4- and the 1:2: 4-paratoIuidioemoDo- 
sulphonic acids {Annalen, ccxxx, 314, 331) are shown to 
be the 1:3:4:6- and 1:2:4: 6 derivatives resped- 
ively. The former, by elimination of the NHa-radicle, 
gives a toluenedisulphonic acid identical with that ob- 
tained from the 1:2: 5-orthotoluidinesuIphonic acid by 
the xanthate method. 

X : 2 : 4 • Parachlorotoluenesulphonic acid, prepared 
from the corresponding amido-acid, gives a sparingly 
soluble barium salt, a chloride melting at 23 — 24^, and an 
amide melting at 142°. On sulphonation with 20 per cent 
anhydrosulphuric acid, it yields, as sole produd, an acid 
identical with that obtained from the 1:2:4: 6-para* 
toluidinedisulphonic acid. 

1:3:4- Parachlorotoluenesulphonic acid, obtained 
from the corresponding amido-acid, gives an easily soluble 
barium salt, a chloride crystallising in plates melting at 
54°, and an amide melting at X54°. On sulphonation with 
20 per cent anhydrosulphuric acid, two disulphonic acids 
are obtained, the chief produd being the xT3\:4:6- 
derivative, since it is identical with the acid obh^ned 
from the X : 3 : 4 : 6-paratoluidincdi8uIphonic acid. 



Crimicax. Nbwi, ) 
Ang, 2, 1895. I 



Constitution of Pseudaconitine. 



59 



Parachlorotolaene, on salphonation with 20 per cent 
anhydrosulphuric acid ander similar conditions, gives a 
mixture of the 1:2:4:6- and 1:3:4: 6-di8ulphonic 
acids in the proportions of about three parts of the former 
to one of the latter. 

The 1:2:3: 5-orthoteluidinedi8ulphonic acid prepared 
by Hasse's method {Annalent ccxxx., 286), and shown to 
be identical with Hasse's produd by conversion into the 
bromotoluenedisulphonic chloride, gives, by the hydrazine 
method of eliminating the NHa-radicle, a toluenedisul- 
phonic acid, which differs from that described by Hasse, 
since its chloride (CI found 24*5, Hasse 25*9, theory 24*6) 
melts, not at I32^ but at 95°. 

I : a : 5-Orthochlorotoluenesulphonic acid gives, on 
farther sulphonation, a produd which seems to differ from 
that obtainable from Hasse*s acid by Sandmeyer*8 
method, and is being farther examined. 

In addition to the known 1:2:4-, 1:2: 5-, and 
1:3: 5-toluenedisalphonic acids, the following have been 
prepared : — 

1:2: t-Tolutnidisulphonic aeid, obtained from the 
1:2:4: 6-paratolaidinesalphonic acid, by eliminating 
the NHa-fA^icle, forms a potassium salt crystallising with 
liH^O in minute prisms, and a chhridi, crystallising in 
scales, melting at 99^ 

1:3: ^'Toluentdisniphonic acidf obtained from the 
1:3: 4-paratoluidinemetasalphonic acid by the xanthate 
method, forms a mono-hydrated potassium salt crystal- 
lising in needles, and, on treatment with phosphorus 
pentachloride, yields the chloride^ which crystallises from 
benzene with i mol. proportion of benzene in large prisms 
melting at about 60°, and from petroleum spirit in scales 
melting at 1x1°. 

103. *' ContribuiioHs to our Knowledgi of the Aconiti 
Alkaloids.'' Part XII. •• The Constitution of Pseudaconi- 
tine, Preliminary Notice,*' By Wyndham K. Dunstan, 
P.R.S., and Francis H. Carr. 

Pseudaconitine is the name given by Alder Wright to 
the highly toxic alkaloid contained in Nepaul aconite 
{Aconitum ferox). It is a crystalline base, melting at 
Z04 — 105^ whose composition is expressed by the formula 
C36H49NOia* When hydrolysed it furnishes, according 
to Alder Wright and Luff (Trans, Chem. Soc, 1878), 
pseudaconine and one molecular proportion of dimethyl- 
protocatechuic acid (veratric acid), — 

C3«H4gNO,a+ HaO « Ca7H4iNOg -h CgHio04. 
The authors are engaged in a re-investigation of this 
alkaloid in the light of their recent work on the constitu- 
tion of aconitine derived from Aconitum napellus (Trans, 
Chem, Soc., 1894, 176, 290). 

The pseudaconitine employed by the authors was ex- 
traded from the roots of Aconitum ferox, some of which 
were provided by the Qovernment of India through the 
Impenal Institute. The highly-purified crystalline base 
melted at 201", that is, nearly zoo^ higher than the point 
recorded by Wright and Luff; this melting-point waft not 
changed by fradional crystallisation. 

When heated slightly above its melting-point, pseud- 
aconitine loses a molecular proportion of acetic acid, 
leaving a new base, which it is proposed to name pyro' 
psiudaconitint. This alkaloid, on hydrolysis, loses a 
molecular proportion of dimethylprotocatechuic acid, 
fomishing pyropseudaconine. 

On complete hydrolysis with alkali, pseudaconitine 
yields, in addition to the dimethylprotocatechuic acid ob- 
served by Wright and Luff, a molecular proportion of 
acetic acid, which was identified and estimated in the 
manner described in the authors' previouk paper on 
aconitine. 

When pseud aconitine sulphate is heated in a closed 
tnbe with water, it suffers, like aconitine, partial hydro- 
lysis, the acetyl group alone being eliminated, producing 
a molecular proportion of acetic acid. In this aAion a 
new alkaloid is formed, corresponding with the benzaco- 
nine derived in a similar manner from aconitine, which 



the authors propose to name viratrylpsiudaeonim. This 
substance is a crystalline base (m.p. z8i^) which, when 
hydrolysed, furnishes pseudaconine and dimethylproto- 
catechuic acid (veratric acid). 

There is therefore a close resemblance between the 
constitution of aconitine and of pseudaconitine, both 
alkaloids undergoing hydrolysis in a similar manner. The 
molecile of each alkaloid contains an acetyl group ; but 
in psnidaconitine the benzoyl group of aconitine is re- 
placed by the veratryl group, aconitine being acetyl- 
hentaconine, and pseudaconitine acetylveratry^seudaco' 
nine. As far as the authors' investigation has proceeded, 
pseudaconine appears to be distinAly different from the 
aconine derived from aconitine. There is little reason at 
present to doubt that the crystalline highly adive alka- 
loid isolated by the authors is identicau with Wright's 
pseudaconitine, but further evidence on this point is being 
obtained. 

Library, 

The Library will be closed during the last fortnight in 
August for cleaning and the annual revision of the 
Catalogue. Fellows are requested to return all books in 
their possession not later than August Z5th. 

Research Fund, 

The following grants have been made by the Council 
on the recommendation of the Research Fund Com- 
mittee : — 

£30 to Messrs. J. J Hummel and A. G. Perkin, for 
the investigation of certain nattiral colouring- 
matters. 

£10 to Dr. H. Ingle, for the purchase of variotis alde- 
hydes, ketones, and hydrazine, to continue his work 
on stereoisomeric psazones. 

£zo to Dr. J. J. Sudborough, to continue his work on 
diortho-substituted benzoic acids. 

£1$ to Mr. £. Haworth, for the synthesis of an acid 
having the composition C8Hx4(COOH)af and the 
comparison of its properties with those of cam- 
phoric acid. 

£$ to Mr. R. B. Doran, for a research on the prepara- 
tion of mustard oils by the readtion of chloro- 
carbonic esters with lead thiocyanate. 

£15 to Dr. W. A. Bone, to continue a research on the 
substituted succinic acids, and on the behaviour of 
various trimethylene compounds on treatment with 
the sodium compound of ethylic malonate. 

;f xo to Dr. B. Lean, to extend his work on the deriva- 
tives of ethylic butane tetracarboxylate. 

;f20 to Dr. J. Walker, for an investigation of the con- 
ditions of equilibrium between the cyanates and 
the corresponding ureas. 



NOTICES OF BOOKS. 

Th4 Mechanical Auxiliaries of Chemical Technics, (** Die 
Maschinellen Hilfsmittel der Chemischen Technik "). 
By A. Parnickb, Civil Engineer, formerly Head- 
Bngineer at the Grielheim Chemical Works. With 
337 Illustrations. Frankfurt-on-Mayn : H. Bechold. 
1894. Svo., pp. 320. 
That a work of this charader should have been found 
requisite is a striking proof of the development of the 
chemical industries in Germany. It is now found neces- 
sary that the technical chemist should possess a clear and 
comprehensive acquaintance with the mechanical auxili- 
aries which he has to employ. On the small scale in the 
laboratory, the skilled hand of the chemist brings into 
mutual contad in their due proportions and conditions 
the substances which have to read. But when we transfer 
the process from the laboratory to the works, and employ 
hundred-weights in place of grms., there arises a new task. 



6o 



Heating'^power of Wyoming Coal and Oil. 



I CttBMICAL N.BWS, 

I Aug. a. X895. 



Mechanical au^tiliaries have to be devised which may 
take the place of the skilled hand, and on their presence 
Qr absence, or rather on their perfeiSlion or defedkiveness, 
the whole question of successor failure may turn. 

To take an instance. The ammonia-soda process was 
invented and patented in Britain long before the days of 
Solvay. But the mechanical appliances for carrying 
out the rea^ion were so imperfeA that the process was a 
commercial failure until better appliances were devised 
by Solvay and his coadjutors, when ammonia-soda be- 
came a formidable rival to the Leblanc process. Other 
similar cases might readily be found, and it will strike the 
reader that readions have been conceived which remain 
a dead-letter because the arrangement and construdion of 
the proper plant has presented difficulties not yet sur- 
pounted. 

Hence the technical chemist, without seeking to become 
a jack-of-all-trades, ought to have a general acquaintance 
with the appliances used for the various types of chemi- 
cal processes, so that he may seled such as are likely to 
suit his exad purpose. He must be able to come to an 
understanding with the mechanical engineer, and to ex- 
plain precisely what he wants. Hence the work before 
us, compiled as it is by an experienced specialist, will be 
of great service to graduates of universities and poly- 
technics on their entrance into a pradical career. 

After a few useful generalities, the author treats 
systematically of sources of power, of the transmission of 
power, and of contrivances for the conveyance of material 
produAs. Under this last heading is included the re- 
moval of offensive or pernicious vapours. These, it is 
said, are not to be conveyed into the soil, though the 
author^ very questionably, seems to sanction their dired 
introduAion into water. 

The fourt^ sedion discusses machines for comminution, 
including disintegrators, indigo-mills, and colour-mills. 
Mixing machines are described adapted for solids alone, 
liquids alooe,and for incorporating solids with liquids and 
gases. 

* Next follow appliances for fusion, solution, and lixivia- 
tion, for concentration and vaporisation, for mechanical 
separations (Including extradion and fradionation). Here 
are included filter-presses, appliances for separation by 
crystallising, by sublimation, and by refrigerating 
machines. 

Mention is made of the increasing preference shown 
for the ammonia process as compared with the use of car- 
bonic acid. 

- Desiccatory apparatus forms the subjeiSt of the ninth 
chapter, and in the tenth we have an account of appara- 
tus for determining weight, temperature, pressure, and 
draught of gaseous current. An instrument devised by 
Arndt bears the remarkable name of the ** econometer," 
and is here figured. It consists of a gas balance depend- 
ing on a novel principle, and fixed in an air-tight case. 
The illustrations of the work are not only numerous, but 
for the most part very well drawn. Many of them, how- 
ever, have a very annoying fault ; the lettering is done, not 
with printing charaders, but with script, and to make 
matters worse, with German script. As instances we 
may mention Figs, aoa, 203, 224, &c. This is the more 
remarkable as the larger portion of the illustrations are 
lettered in a rational manner with printing cbaraAers. 



How Shall Young Men be Educated in Applied Chemistry ? 
By P. T. Austen, Ph.D., F.C.S., Prolessor of Chemis- 
try in the Brooklyn Polytechnic Institute. 

Concerning this essay we may say that, in part, Prof. 
Austen's advice to students is exceedingly judicious, and 
his demands thoroughly rational. But in part it must 
be confessed that his requirements are exorbitant, leading 
merely to a waste of time and of brain-power. What 
must be thought, e.g.^ of the following programme ? "A 
thorough grounding in history, the elements of law, 



political economy, metaphysics, logic, ethics, and litera- 
ture should be effeded.'' We submit that to the man of 
science history, other than the history of discovery and 
invention and their treatment by the world, is little better 
than fossil gossip; political economy and metaphysics 
must rank as a waste of time. The same should be re- 
marked concerning mere ratiocinative logic, ethics, and 
literature. The elements of law are admissible merely as 
far as patents and sanitary regulations are concerned. 
On other matters, and on general principles, in as far as 
such can be said to exist, the technical chemist may well 
be referred to solicitors and counsel, remembering that 
his opinion on legal questions will only be received by the 
courts with derision. 

The technical chemist will, of course, require to be well 
grounded in physics, especially in thermotics, optics, and 
eleiStricitjr. Nor should mathematics be overlooked ; but, 
on the principle of the division of labour, the ** business 
side of industrial chemistry " had better be left to book- 
keepers and accountants. 

A knowledge of the German and French languages is, 
of course, indispensable. 

Much more useful to the technical chemist than meta- 
physics, ethics, and literature, will be botany and zoology. 
He may often be called upon to study the applicability 
of newly-discovered animal or vegetable produAs and the 
ways of combatting new parasites. 

The author gives also moral lessons. The young works* 
chemist is told to be ** honest to a fault "—an expression 
difficult to understand. He certainly should not cook 
results, but for telling the whole truth and nothing but 
the truth he may earn scant gratitude. We could point 
out a chemist who in his young days got into dire dis- 
grace for reporting the presence of a serious percentage 
of arsenic in a sulphur ore just taken into stock* and 
was cautioned in future to determine nothing in the 
ores but sulphur, copper, and silver. If we, in turn, 
may give a piece of advice, we would caution every 
young technical chemist to shun any industrial establish- 
ment where a '* self-made man " is in course of formation. 

An excellent recommendation given by Prof. Austen is 
that the more advanced students in technical chemistry- 
should not merely seek to make new substances by well- 
known methods — as is largely done, especially in Ger- 
many—but should be praAised in producing known sub- 
stances by new methods. 

The author's essay abounds in suggestions of the 
highest importance, but we are led to (question whether 
in these days the chemical student, if tramed on his lines, 
would not be overwhelmed with matter of very secondary 
value. 



University of Wyoming, Laramie, Wyoming, Depart- 
ments of Chemistry and Mechanical Engineering. 
Special Bulletin. January, 1895. ^''' Heating Power 
of Wyoming Coal and Oil ; with a Description of the 
Bomb Calorimeter. By Edwin E. Slosson, Professor 
of Chemistry, and L. C. Colburn, Professor of 
Mechanical Engineering. 
The authors give a table of the heating-power of Wyom- 
ing coal, and its proximate analysis. They discuss the 
varied efficiency of bodies, mentioning that only from 45 
to 85 per cent of the theoretical evaporation power is 
adually obtained. 

The Wyoming mineral oils are said to possess nearly 
double the heating capacity of the coals from the same 
region. The oils are said to be much like the Baku oils. 
The methods of determining heating-power are next 
considered. Concerning the boiler test it is admitted that 
approximately accurate results can be obtained only from 
an experimental plant. The disadvantages are that the 
experiment is always a test of the efficiency of the furnace 
and boiler, and of skill in firing, rather than a determina- 
tion of the absolute value of the fuel. 
Elementary chemical analysis is a tedious and delicate 



CWBMICAt NlWf , I 

Aof.a, fSgs. f 



Chemical Notices from Foreign Sources. 



61 



process, the rather as the carbon may exist in different 
stated which hare not identical heats of combustion. 

The aothort recognise calorimetry as the most satisfac- 
tory method of determining the heating*power of a fuel, 
For this purpose they prefer the apparatus of Mahler, a 
cheaper modification of the celebrated bombe calori- 
aetnqoe of Bwth^lot. Mahler's instrument is described 
and figured, and the corredions necessary in its use are 
giTen. 

YiMT'Book of Organic Chunistfy, Edited bv Gabtano 

Miififi^Nt, of Palermo. Vol. I., 1893. With a Preface 

by Ernst von Msybr. Large 8vo., pp. xiv. and 88a. 

Leipxig : J. A. Barth. 1895. 

The author endeavours to colled in a single volume all 

newly-obsorved fads in organic chemistry, the results 

both of experiments and speculation. The volume for 

18^ has alreadv appeared, and that for 1894 will, it is 

hoped, be issoed in the course of the present year. 



CHEMICAL 



NOTICES FROM 
SOURCES 



FOREIGN 



l^OTB.— AU dcfrces of temperatare are Centisrade anleii otberwiae 
cxpratMd. 

CompUs Ratdns Htbdomadaira d€S Seances^ de VAcademU 
da Sdemes, Vol. cxxi., No. i, July x, 1895. 

At the meeting of July ist Herr Schwarz was ele^ed a 
correspondent of the Sedion of Geometry, viVi; the late 
Neumann ; Baron Muller was ele&ed a correspondent of 
Botanical Sedion, via the late Pringsheim; and Dr. 
Engelmann was eleAed a corretpoodent of the Sedion of 
Medicine and Surgery, via Herr Heidenhain. 

This issue contains a short obituary notice of Professor 
Huxley, a correspondent of the Sedion of Anatomy and 
Zoology. 

Determination of Small Quantitiet of Arsenic— 
Ad. Camot.— This paper will be inserted in full. 

Oxidation Produ^s of Bensyliden-campbor and of 
Benxyl-campbor. Nttrotate and Nitronitrite of 
BenxvUden-camphor. — A. Haller. — If bensyliden-a- 
benzyl-camphor are submitted to the adion of oxidising 
agenu they are ruptured at the point of attachment of the 
arumatic radicle, and the two nuclei behave then in the 
oxidising medium as if they were free. 

On Paraiungatic Acid.^L. A. Hallopeau.^It is easy 
to obtain solutions of paratungstic acids presenting all the 
known readions of the paratungstates, and becoming con- 
verted into metatungstic acid on ebullition, just as the 
paratungstates are transformed into metatungstates. 
Paratungstic acid therefore really eiists as Laurent main- 
tained, but the little stability of its molecule caused it to 
be split up into tungstic acid and water on the simple con- 
centration of its solutions. This fad alone distinguishes 
it from Qraham*s colloidal tungstic acid, which may be 
evaporated to dryness and heated to 200^ without decom- 
position. 

Determination of Alumina in Phosphates.— Henri 
Lasne.— This paper will be inserted in full 

On Sodium Amidide.— M. de Forcrand.— A thermo- 
chemical paper, not adapted for useful abstradion. 

Phosphoric Bthers of AUylic Alcohol. Allylphos- 

Siboric Acid. — J. Cavallier. — Allylnhosphoric acid 
as the composition P04C3H5Ha. With coloured rea- 
gents it behaves like most of the oay-acidsof phosphorus. 
Neutrality with methyl orange is obtained by the addition 
of I moL of soda and neutrality with phenolphthalein by I 
a mole. It forms tvro series of salu: nentnl laltSi I 



P04CtH3Ma, and acid salU, PO4C5H5MH. The author 
describes the most important salts of l>oth series. 

Preparation and CondoAivity of New Cyanometb* 
inic Ethers.— J. Ouinchant.— Not admitting of useful 
abstradion and not of sufficient moment to claim insertion 
in full. 

No. a, July 8, 1895, 

Adiion of Zinc Chloride upon Retorcine. — B. 
Orimaux.— The author obtains a substance fusible at 
225^. It forms small colourless needles soluble in alco- 
hoi, acetone, sparingly soluble in ether, and soluble in 100 
parts of boiling water. Its cold watery soletioo has a 
blue fluorescence, which is stronger if dissolved in alkalisi 
in ammonia, or in concentrated sulphuric acid. This sub* 
stance is identical with umbelliferone, CqHsOi. Another 
substance formed, Ca4Hi805, is fusible at 264^ It is in- 
soluble in water, soluble in alcohol, acetone, and ether. 

Volumes of Salts in their Aqaeoat Solutions.— 
Leco<| de Boisbaudran.— This paper requires the accom- 
panying diagram. 

On Dipbenylantbrone.— A. Haller and A. Quyot.— 
The researches of the authors show that the compound 
C26H18O obtained by various procedures enumerated may 
be considered as diphenylanthrone. As the constitution 
of this substance is established, we are warranted in at* 
tributing to phthalyl tetrachloride, fusible at 88*— a 
scheme which makes of it a disymmetric molecule* 
Phthalyl dichloride contains tetrachloride. 

DireA Spedral Aoalyais of Minerals and of ceruin 
Melted Salts.— A. de Gramont. 

Determinationa of the Solubility of Some Organic 
Compounds in Carbon Diaulphide at very Low Tem- 
peratures.— Henryk Ardowski.— This memoir cannot be 
inserted without the insertion of the complicated diagram 
of curves. 

Certain Oxiditing Properties of Osonised Oxygen, 
and of Oxygen exposed to the Sun't Rays.— A. 
Besson.— The author has formerly shown that osonised 
oxygen ads upon perchloric ethylene, CaCl^ forming, as 
the main produd, trichloracetyl chloride, CCltCOCl, and 
as an accessory produd carbonyl chloride, COCla. He 
has since found that the same produds are equally 
formed if dr^ oxygen is caused to ad upon CaCl4 in pre- 
sence of dirsd solar light. Osonised oxygen and dry 
oxygen, in presence of sunlight, read energetically upon 
the phosphorus iodides, setting free iodine, and forming 
complex produds containing phosphorus, oxygen', and 
iodine. 

Adion of Nitric Oxide upon certain Metallic 
Chlorides, i.^., Ferrous Chloride and the Bismuth 
and Aluminium Chlorides. — V. Thomas. — The 
yellowish brown compound formed from the ferrous 
chloride corresponds in composition with the compound 
obtained by saturating a solution of ferrous chloride with 
nitric gas at temperatures between 22*5* end 25*. Bis- 
muth chloride exposed to the adion of nitric oxide takes 
a yellowish colour, but the readion is complete only after 
the lapse of several days. The compound ultimately ob- 
tained has the composition B1CI3NO. The corresoonding 
aluminium compound has the composition AlaClsNO. It 
has a pale yellow colour. Both the above compounds are 
highly hygroscopic, and the aluminium compound fumes 
on exposure to the air. 

Adion of the Halogeoa upon Methylic Alcohol.— 
— A. Brochet. — This paper is not adapted for abstradion. 

On a Phyaical Theory of the Perception of 
Colours. — Georges Darxens. 



Jievtu UnivfrseiU dts Mims ei de la MtiaUmr^if, 
VoL XXX., No. a. 
This issue contains no cheoitcal matter. 



62 



City and Guilds 0/ London Institute. 



I CRBurcAL Nswt, 
« Aug. a, 1895. 



MISCELLANEOUS. 



PrelimfDaijf Retearchet on the Hydrolysis of the 
Aqueous Solutions of Mercuric Chloride. — Henryk 
Arctowski. — The author has the ultimate purpose of 
expounding our entire knowledge on the chemical adkion 
of water upon salts. For the present he restriAs himself 
to the case of mercuric chlondt.-^ZiUschrift fur Anorg, 
Chimit* 

Preseryation of Wheat.— M. Balland.— The author, 
quoting Duharoel du Moncesu, mentions an experiment 
made on 94 cubic feet of wheat of the crop of 1743, which 
he had preserved for more than six years with the sole 
precaution of occasional ventilation, and which was not 
in the least impaired. Parmentier mentions that in 1774 
the King and the royal family tasted bread made of wheat 
which had been kept for 221 years, and which had been 
deposited in the citadel of Metz since 1523. The method 
of preservation is not mentioned.— Com^/#5 Rendus, cxx., 
No. 35. 

City and Guilds of London Institute. — The 
Diploma of ** Associate of the City and Guilds of London 
Institute " has been conferred by the Council of the 
Institute upon the following matriculated students, who 
have this year successfully completed the full course of 
instrudion at the Central Technical College :— 

Civil and Michanical fifi^iit#^riit/.—H. S. Andre wes, 
F. G. Arnould, J. E. Chapman, H. £. Fenwick, C. S. 
Hainworth, E. W. Haioworth, B. H. M. Hewett, E. W. 
Hummel, F. T. W. Lewis, F. E. Morgan, R. E. Reeves, 
H. Robinson. 

Appliid Physics and Electrical Enginaring. -^J. M. 
Bsrr, S. Beeton, C. Brandeis, W. M. Carver, A. D. Con- 
stable, S. Gilford, F. S. Grogan, A. C. Hanson, G. S. 
Hewett, C. D. Le Maistre, P. G. Phelps, W. Reilly, W. 
Roberts, H. G. Solomon, R. J. J. Swann, C. P. Taylor, 
E. L. Thorp, E. L. Webb, N. J. Wilson. 

Applied Chemistry.— W. G, Bennett, W. A.. Davis, 
W. T. Gidden, C. Revis, E. M. Rich, P. Spencer. 



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Qualitative Analysis of Solution containing Hydric Sulphide. 63 



THE CHEMICAL NEWS. 

Vol. LXXII., No. 1863. 



A SCHEME FOR QUALITATIVE ANALYSIS 

OP A 

SOLUTION CONTAINING HYDRIC SULPHIDE. 

HYDROSULPHIDE, SULPHIDE. POLY- 

SULPHIDE, THIOSULPHATE. SULPHITE, 

AND SULPHATE. 

By W. P. BLOXAlf , B.Sc (Lond.). 

In the Chemical Nxws (Ixxii., p. 39) there appears a 
commaoication from R. G. Smith, B.Sc, entitled ** The 
Detedion of Salphates, Sulphites, and Thiosulphates, in 
Presence of B^ Other.*' In this commanication the 
author provides for the deteAion of sulphates, sulphites, 
and thiosulphates, and in conclusion states that ** Hydro- 
solphnrtc acid would interfere with these readions, and 
ought to be eliminated by bubbling carbon dioxide through 
the solution until the gas escaping from the tube no longer 
darkens lead-paper.** 

Without ofifering further criticism than that the presence 
of hydric sulphide vitiates entirely any attempt to sepa- 
rate sulphate, sulphite, and thioiulphate, whilst the 
method recommended for its removal is tedious, an 
outline of process it here given which has proved satis- 
fadory in dealing with solutions containing normal 
•olphides, polysulphides, hydrosulphide, free hydric sul- 
phide* stilpnite, sulphate, and thiosulphate. 

The necessity for such a process arose in the course of 
an investigation of the produds of decomposition, on air 
espoanre, of the laboratory agent known either as ammo- 
nium sulphide or ammonium hydrosulphide. The results 
of this investigation were communicated to the Chemical 
Society on June X5th, 1893, the paper being entitled 
"The Sulphides and Polysulphides of Ammonium.*' An 
abstrad of this paper appeared in the Proceedings of the 
Ckem'ual Society, Od. 19th, 1893. '^^^ P^P^i* appeared at 
length in the yonmal of the Chem, Soc, Trans, (Ixvii., 
April, 1895). In it the following statement occurs 
(p. 278):—** The first point was to determine what am- 
monium compounds, other than sulphide and polysul- 
phide, were present, and this involved the removal of 
•olphide and polysulphide, and the recognition in the 
filtrate of sulphite, thiosulphate, and sulphate. A scheme 
for separation is given by Fresenius (' Chemical Analysis 
—Qualitative, translated by C. E. Groves from the X5th 
German Edition,' p. 194), but it was found to require mo- 
dification before successful results could be obtained, 
owing to the difficulty of removing the last traces of hy- 
drogen sulphide. An account of the modified method of 
anuysis will appear in another journal." 

Tne author had in view publication in the Chemical 
News, and the appearance of Mr. Smith's paper induces 
him to make good his negled. 

The statement of Fresenius is as follows :— ** When, as 
is often the case, it is reijuired to find sulphites and hypo- 
sulphites of the alkalies m presence of alkaline sulphides, 
solution of sulphate of zinc is first added until the sul- 
phide is decomposed ; the sulphide of sine is then filtered 
off. and one part of the filtrate is tested for hypo- 
solphnrous acid by addition of acid, another portion 
for sulphurous acid with nitroprusside of sodium, &c.*' 

The treatment prescribed by Fresenius [Ibid,, p. 193)^ 
for the detedion of sulphurous acid is as follows : — *' If 
an aqueous solution of an alkaline sulphite is carefully 
neutralised with acetic acid, or bicarbonate of soda is 
added to it, according as it has an alkaline or acid readion 
(esc€M of the bicarbonate is without effed, but excess of 



caustic alkali or simple carbonate, or of carbonate of 
ammonia, prevents the readion), and a relatively large 
amount of solution of sulphate of sine, mixed with a very 
small quantity of nitroprusside of sodium, be then added, 
the solution will become red if the quantity of the sul- 
phite present is not too small; when, however, the 
amount of sulphite is very minute, the colouration makes 
its appearance only after the addition of some solution of 
ferrocyanide of potassium. If the quantities are not 
altogether too minute, a purple-red precipitate will form 
on the addition of the ferrocyanide of potassium 
(Bodeker). Hyposulphites of the alkalies do not show 
this readion." 

Being unable to obtain by purchase ammonium sulphite 
or ammonium thiosulphate in a state of purity, Mr. 
>y. B. Giles, JF. I.e., kindly undertook their prepara- 
tion, and was eminently successful Analysis of the pure 
salts showed the following composition :— 

a(NH4)aS03+3HaO and (NH4)aSa05. 

Experiments were made with mixtures of these salts 
according to the method of Fresenius. It was found, 
however, that contrary to the statement of Fresenius 
(loc, cit,) the presence of excess of ammonia enhanced 
the delicacy of the test for sulphite. Experiments de- 
monstrated the possibility of deteding very small traces 
of sulphite mixed with excess of thiosulphate 

On enlarging the scope of experiments so as to deted 
sulphite and thiosulphate in a solution containing sulphide 
and polysulphide, difficulty was experienced in getting rid 
of the last traces of hydric sulphide by precipitation as 
sine sulphite. The solution being treated as recom- 
mended with sine sulphate, and the precipitate removed 
by filtration, any trace of hydric sulphide left in the fil- 
trate effedually masks the red colouration given fay 
sulphite, the ordinary readion of sulphides with sodium 
nitroprusside taking its place; experiments showed that ad- 
dition of solution of cadmium sulphate would determine 
the complete removal of hydric sulphide. It was conse- 
quently employed in place of zinc sulphate, but the 
sulphite readion was not obtained on adding nitro- 
prusside and ferrocyanide. On addition to the filtrate of 
zinc sulphat^, however, the readion for sulphite was ob- 
tained, showing that the presence of cadmium sulphate 
did not prevent the detedion of sulphite, whilst it eneded 
the complete removal of hydric sulphide. Solution of 
cadmium chloride was employed with similarly successful 
results, and solution of zinc chloride was successfully 
substituted for one of zinc sulphate, with a view of elirat- 
nating sulphur compounds from the reagents used. 
Using mixtures of sulphide, polysulphide, sulphite, and 
thiosulphate, the influence of the following substances on 
the test was investigated, viz., ammonium chloride, 
ammonium carbonate, and free ammonia, the results 
indicating that they did prevent the detedion of sulphite. 
A modified method of testing was accordingly adopted. 
A mixture of solutions of zinc chloride, cadmium chlo- 
ride, ammonium chloride, and ammonia, was made in a 
stoppered cylinder. To this was added the solution con- 
taining sulphide, polysulphide, sulphite, and thiosulphate 
of ammonium. From time to time the mixture was 
gently agitated, and the air of the cylinder tested with 
paper moistened with solution of ammoniacal plumbic 
acetate. When the air was proved free from hydric sul- 
phide, filtration was effeded, and a few drops of the clear 
filtrate tested with solution of ammoniacal silver nitrate. 
If no colouration or precipitation was observed, the tests 
for sulphite and thiosulphate were then made. It was 
found by this method that even very small traces of sul- 
phite could be deteded with certainty. Experimenting in 
this fashion upon laboratory samples of coloured ammo- 
nium sulphide, it was determined that they contained 
thiosulphate, but only traces of sulphite. Under these 
circumstances it was suspeded that during the progress 
of the test oxidation had taken place, sulphite becoming 
sulphate. Accordingly the fiHratee, after separation (m 



64 



Quantitative Separations of Mttals. 



f CRIUICAL NBWt, 

I Aug. 9« 1895. 



sulphide and polysulphide, were rendered strongly acid 
with hydric chloride (free from chlorine), and boiled to 
expel sulphur dioxide. The deposited sulphur was fil- 
tered off, and the filtrate tested for sulphate. Only the 
Slightest traces could be detected, and these were attri- 
buted to the hnperfed washing of hydric sulphide during 
saturation of anmionia with gas generated by the aAion 
of hydric sulphate on ferrous sulphide. 

It being established that oxidation of sulphite did not 
occur in the course of analysis, experiments were now 
made upon mixtures containing sulphide, hydrosulphide, 
polysulphide, sulphite, thiosulphate, and sulphate of am- 
monium. 

The solution was treated as previously described, with 
the mixture of zinc chloride, cadmium chloride, ammonic 
chloride and ammoniai and the filtrate (containing sul- 
phite, thiosulphate, and sulphate) divided into two por- 
tions. One portion was treated as previously described 
for the detedion of sulphite and thiosulphate. The other 
portion was treated as follows, for the detedion of sul- 
phate in presence of sulphite and thiosulphate : - The 
solution, after addition of a small quantity of pure sodic 
hydric carbonate, was placed in a flask, the cork of which 
was pierced by three boles. Through an inlet tube a cur- 
rent of washed carbon dioxide was admitted, and an outlet 
tube was provided dipping below the surface of water. 
Through the third hole, a small stoppered separating 
funnel passed, the tube reaching nearly to the bottom of 
the flask. 

Through the cold solution a current of washed carbon 
dioxide was passed, and the liquid gradually raised to the 
boil. When all air was expelled, hydric chloride (free 
from chlorine) was cautiously admitted by the stoppered 
separating funnel. When excess of acid had been added 
the solution was boiled down to one-fifth of its original 
bulk, the current of carbon dioxide being maintained. 
The concentrated liquid was filtered from deposited 
sulphur, and a portion of the filtrate tested with ammo- 
niacal silver nitrate to guard against undecomposed 
thiosulphate. If found to be free the remainder was tested 
for sulphate. 

By these methods mixtures containing sulphide, hydro- 
sulphide, polysulphide, sulphite, sulphate, and thiosul- 
phate, have been successfully treated. 

Some experiments have been made with a view to 
deteding the constituents of mixtures containing poly- 
Ihionates in addition to the sulphur compounds already 
dealt with, and the results will be communicated to the 
Chemical Nbws in due course. 

Royal Naval CoUege» Greenwich, S.E. 



PREPARATION OF THIOACETIC ACID, 

AND ITS IMPORTANCE FOR CHEMICO-LEGAL 

INVESTIGATIONS. 

By ROBERT SCHIFF. 

Some months ago I proposed to abandon, in analytical 
operations, the unpleasant and tedious use of sulphuretted 
hydrogen, and to apply in its stead thioacetic acid. 

This convenient procedure has hitherto been adopted in 
but few laboratories, chiefly, as I learn, from the difficulty 
of preparing large quantities of thioacetic acid by the 
known methods. The methods of preparation described 
in chemical literature are all useless. Even that of Ktkul^ 
and Linnemann with phosphorus pentasulphide and 
glacial acetic acid gives enormously bulky black tumid 
masses, which at once fill the largest vessels, and compel 
the distillation to be broken off. By the following pro- 
cedure we may work with any quantity at pleasure. . 

One part by weight of powdered phosphorus pentasul- 
phide is mixed with i part by weight of fragments of glass 
(not tOQ small) and i part of glacial acetic acid, and the 



mass is placed in a glass vessel fitted with a thermometer 
and an ascending condenser, and heated upon the wire 
gauze with a luminous flame. The readion begins with* 
out any troublesome tumeiadtion, and is easily regulated 
by means of the flame. 

When the temperature of the vapours has risen to about 
103**, the process is interrupted. The yellow produiSl is 
redified, and the portion which passes over between .92^ 
and 97*'~pure thioacetic acid — is used, either in the (^ee 
state as a 6 per cent aqueous solution, or as a salt in a 
30 per cent feebly ammoniacal solution. We thus obtain 
pure thioacetic acid amounting almost to one-third of the 
acetic acid used. For each operation I use in a 2 litre 
flask 300 grms. phosphorus pentasulphide, 150 grms. 
broken glass, 300 grms. glacial acetic acid, and obtain 97 
to 100 grms. of reSified thioacetic acid. This quantity, 
which does not require an hour to prepare, forms 300 c.c. 
of thioacetic solution, and suffices for more than 150 
ordinary qualitative operations. 

In the glass vessels there is left a hard black mass, 
which can be removed by heating with soda-lye. To save 
the trouble of cleansing, I use the well-known wine flasks- 
common in Tuscany. These, without their straw cases,- 
cost about 7 centimes ; they are made of good thin green 
glass, and contain 2| to 2i litres. I cut off two-thirds of 
the neck, melt off the aperture, inserting it in an ascend- 
ing T-tube. When the reaAion is completed the flask is 
thrown away. 

All the operation is performed under a good draught- 
hood with a large flame burning in order to burn all 
escaping gases of an evil odour. 

This thioacetic method is, as it appears to me, impor- 
tant for the qualitative and quantitative recognition of 
arsenic in chemico-legal investigations. I have formerly 
mentioned that if a hydrochloric solution of arsenious or 
arsenic acid is boiled with thioacetate for about a minute, 
when the liquid is cold the arsenic is found to have been 
quantitatively precipitated from the clear liquid. 

The difficulty of maintaining a long-continued current 
of hydrogen sulphide, absolutely free from arsenic — as 
required for judicial purposes— is well known. On the 
contrary, rediified thioacetic acid is always absolutely free 
from arsenic— B«rff/(/^, xxviii., p. 1204. 



QUANTITATIVE SEPARATIONS OF METALS 

IN ALKALINE SOLUTIONS BY HYDROGEN 

PEROXIDE. 

By P. JANNASCH and E. v. CLOEDT. 

Separation of Bismuth. Lead, and Manoanbsb 
FROM Mercury. 
X. Separation of Bismuth J rom Mercury, 
As an initial point for their experiments the authors 
used pure metallic bismuth and mercuric oxide. The 
weighed quantities were heated in a covereJ porcelain 
capsule with 10 c.c. of concentrated nitric acid and 
50 c.c. of water on the water-bath, until completely di*. 
solved. The liquid is then slowly poured into a mixttire 
of 25 to 30 c.c. of concentrated ammonia, 25 c. c. of hy- 
drogen peroxide at 3 to 4 per cent, and 50 c.c. of water. 
There ensued a brisk effeivescence of escaping oxygen, 
and the bismuth subsided as a yellowish-grey deposit of 
hydrated peroxide. It was then dissolved on the Alter in 
dilute hot nitric acid, again precipitated as before, filtered, 
and weighed in a platinum crucible as bismuth per- 
oxide. 

Since for precipitatinjg the bismuth we used hydrogen 
peroxide purified by distillation in vacuo, no corredoft for 
silica, alumina, &c., is needed. Siill we must advise that 
the pure hydrogen peroxide should be used as fresh as 
possible, since its solutions on prolonged standing seem 
to attack sensitive kinds of glass, and may thus be anew 
contaminated with silica. 



Chimical Nbw8» { 
Aug. 9, ia95. / 



Absorption-Spectrum of Liquefied Air. 



If the first deposit of bismuth is washed with extreme 
care, a single precipitation is sufficient for accurate sepa- 
ration. We have proved this in a couple of special 
experiments. 

For the determination of the mercury the entire ammo- 
ntacal filtrate is evaporated down for the complete 
expulsion of the excess of ammonia, strongly acidified 
with sulphurous acid, the liquid poured into a larger 
beaker, diluted to at least 300 c.c, and Ustly precipitated 
at a moderate heat with sulphuretted hydrogen. The 
further treatment of the mercury sulphide and its weighing 
are e ffeded in the usual way. 

2. Separation of Lead and Mercury, 
. The separation is efTedled by pouring the solution of 
the nitrate, acidified with nitric acid, into the ammoniacal 
oxidising liquid. The results are very satisfactory. It 
must be observed that, prior to filtration, the lead preci- 
pitate is allowed to stand for some time (thirty minutes to 
one hour), with occasional stirring, as otherwise traces of 
lead may remain in solution. The lead hydro- peroxide is 
filtered off, well washed with cold water, dissolved on the 
filter in dilute nitric acid (equal to about 10 c.c. of the 
concentrated acid), with a simultaneous addition of hy- 
drogen peroxide, and precipitated again in the same 
manner, 

3. Separation of Manganese and Mercury, 
The separation of these metals is effeiSted with great 
ease, which appears the more remarkable as manganese — 
in consequence of its tendency, when in the state of per- 
oxide, to carry other oxides down with it— is apt to frus- 
trate the smooth course of an analysis. The authors took, 
as their initial point, manganese-ammonium sulphate and 
mercuric oxide. From 0*3 to 0*4 grm. of each substance 
was dissolved in 50 c.c. water and zo c.c. of concentrated 
nitric acid. This mixture is added to a liquid of 30 c.c. 
hydrogen peroxide, 30 c.c. strong ammonia, and 50 c.c. 
water. After heating for thirty minutes in a covered 
beaker on the water-bath, the precipitate is filtered and 
washed with a mixture of water, ammonia, and hydrogen 
peroxide, and finally with hot water. The precipitate 
may be ignited in a platinum or porcelain crucible, either 
whilst still moist or after a partial drying. The coarser 
particles are carefully crushed, and the ignition is conti- 
nued until the weight becomes constant. — Zeitsckri/t fier 
Anorganitche C hemic. 



ON THE 

ABSORPTION - SPECTRUM OF LIQUEFIED AIR. 
By Profetiort LI VEIN G and DEWAR. 

In a recent conversation on the absorptlon-spedrum of 
liquefied oxygen, M. Cornu suggested to us that it would be 
interesting to examine if the diffused absorption bands 
would develop as well when the density of oxygen is pro- 
duced by a reduction of temperature at atmospheric pres- 
sure, as when the gas is compressed at higher tempera- 
tures. 

M. Janssen has found that the intensity of these bands 
increases as the square of the density of oxygen, and has 
recently verified this result by observations of the solar 
spe^rum in the desert of Sahara. This law, as we have 
already pointed out {Proc, Roy, Soc, xlvi.,p. 228), seems 
to indicate that these bands are due either to CQmplex 
molecules produced by condensation, or to the encounters 
of molecules of an ordinary mass— encounters which are 
more frequent when their free path is diminished. 
. To reply to M. Cornu*8 question, we obtained liquefied 
air diredly from the atmosphere by the cold due to the 
rapid evaporation of liquid oxygen under a low pressure. 
The method and the apparatus have been already de- 
scribed by Prof. Dewar {Proc, Royal Institution, xx., 
January, 1893). 

The absorption due to liquefied air of the thickne&s of 



1*9 cm. was then compared diredly with that of liauid 
oxygen, of the thickness of 0*4 cm. The light which had 
traversed this latter medium was introduced, by means 
of a refle(Slion-prism, into the field of vision of the speiSlro- 
scope at the same time as that which had traversed the 
liquid air. The position of the lamps was then regu- 
lated so that the brightness of the spedral regions 
free from bands was the same in the two spedra. 
Under these conditions it was observed that intensity 
of the absorption-bands was developed much more by 0*4 
cm. of liquid oxygen than by a depth of liquid air five 
times greater. 

The vessels containing the liquids were open, the liquid 
air evaporated gradually, and as the boiling-point of 
nitrogen is below that of oxygen the nitrogen evaporated 
more rapidly, and the residual liquid contained a greater 
and greater proportion of oxygen. Therefore the absorp- 
tion-bands become more and more intense, until they sur- 
passed in intensity that of the slighter depth of oxygen. 

Another portion of air liquefied like the former was 
rapidly mixed with an equal volume of liquid oxygen, and 
the absorption of this mixture was compared as above 
with that of liquid oxygen. We recognised that the ab- 
sorption of 2*4 cm. of the mixture was much greater than 
that of 0*4 cm. of liquid oxygen. The density of the oxygen 
in this mixture was, in fadt, three times greater than that 
of the oxygen in pure liquefied air, and, according to the 
law of Janssen, the absorption ought to become nine 
times greater. Our observations, therefore, agree with 
this result. 

These observations agree also with the theory of the 
continuity of the liquid and the gaseous states. We must 
remember that air boils at a temperature lower than does 
oxygen, so that the two liquids to be compared were not 
at the same temperature by about 10°. 

If the diffused absorption-bands of oxygen are produced 
by their mutual collisions in the gaseous and liquid states, 
it is permissible to suppose that they would be profoundly 
modified if the oxygen assumed the solid state. Hitherto 
oxygen has not yet been solidified in a state of purity, but 
liquid air is easily brought to the solid state by rapid 
evaporation under a low pressure (Dewar, Proc, Royal 
Institution, January 19, 1894). 

Whether the solid thus obtained is homogeneous, or 
merely formed of a paste of solid nitrogen mixed with 
liquid oxygen, may be open to discussion, but in any case 
it is beyond doubt that the oxygen is at the lowest tem- 
perature which has been attained. Consequently, we 
have examined if a difference can be perceived between 
the absorptions of solid and of liquid air. There was no 
difference in the charadter of the absorptions, and very 
little in the intensities. 

To gauge the efiefis of the temperature, we compared 
the absorption of a depth of 3 cm. of liquid oxygen, boil- 
ing under a pressure of about i cm., with that of an 
equal depth of the same liquid at the atmospheric pres- 
sure. With the coldest liquid, the bands in the orange 
and the yellow were appreciably elongated, enlarged 
especially on the more refrangible side. The weak 
band in the green was darker, and the band in the 
blue seemed also somewhat stronger. The difference 
of temperature might be about 17^, which does not 
seem much, though it is about the fifth part of the tem- 
perature of the warmer liquid. — Comptes Rendus, cxxi., 
p. 162. 

Examination of Seed-lac— A. Gascard (youmal dt 
Pharmacie),^Co\^ alcohol at 95 per cent extrads from 
the lac its most important resmous ingredient, which is 
important for the varnish manufadure, and is said to be 
a mixture of several acids of the fatty series, and to con- 
tain nitrogen. The portion soluble in boiling alcohol of 
the srme strength separates out on cooling in the form 
of needles, and has the properties and composition of the 
waxes. It is a mixture of several esters of myricyl alcohol 
with mote than 50 per cent of free myricyl alcohol. 



66 



Spectra of Argon. 



[ Cbbmical Rbws, 
I Aog. ^ 1895- 



ON THE SPECTRA OF ARGON .• 
By WILLIAM CROOKES, F.R.S.. *c. 

T (I ROUGH the kindness of Lord Rayleigh and Professor 
Ramsay I have been enabled to examine the spedrum of 
this gas in a very accurate spedtroscope, and also to take 
photographs of its spedtra in a spe^rograph fitted with a 
complete quartz train. The results are both interesting 
and important, and entirely corroborate the conclusions 
arrived at by the discoverers of argon. 

The results of my examination are given in a table of 
wave-lengths, which follows, and on a map of the lines 
accurately drawn to scale, accompanying this paper. The 
map is 40 ft. long, and the probable error of position of 
any line on it is not greater than i m.m. 

Argon resembles nitrogen in that it gives two distind^ 
spedra, according to the strength of the indudtion current 
employed. But while the two spedra of nitrogen are dif- 
ferent in charadter, one showing fluted bands and the 
other sharp lines, both the argon spedra consist of sharp 
lines. It is, however, very difficult to get argon so free 
from nitrogen that it will not show the nitrogen flutings 
snperposed on its own special system of lines. I have 
used argon prepared by Lord Rayleigh, Professor Ramsay, 
and myself, and however free it was supposed to be from 
nitrogen, I could always at first detedt the nitrogen bands 
in its spedtrum. These, however, soon disappear when the 
indudion spark is passed through the tube for some time, 
varying from a few minutes to a few hours. The vacuum 
tubes l>e8t adapted for showing the spedra are of the 
ordinary PHicker form, having a capillary tube in the 
middle. For photographing the higher rays which are 
cut off by glass I have used a similar tube, ** end on,'' 
having a quartz window at one end. I have also used a 
Pliicker tune made entirely of quartz worked before the 
oxy-hydrogen blowpipe. I have not yet succeeded in 
melting platinum or iridio-platinum wire terminals into 
the quartz, as thev melt too easily, but a very good spec- 
trum is obtained by coating the bulbs outside with tin- 
foil, conneded'with the terminals of the indudiion coil. 

The pressure of argon givingthe greatest luminosity and 
most brilliant spedkrum is 3 m.m. At this point the colour 
of the discharge is an orange-red, and the spedlrum is rich 
in red rays, two being especially prominent at wave- 
lengths 696*56 and 705*64. On passing the current the 
traces of nitrogen bands disappear, and the argon 
snedrum is seen in a state of purity. At this pressure the 

Eiatinum from the poles spatters over the glass of the 
ulbs owing to what I have called *'eleArical evapora- 
tion,"! and I think the residual nitrogen is occluded by 
the finely- divided metal. Similar occlusions are fre- 
quently noticed by those who work much with vacuum 
tubes. 

If the pressure is further reduced, and a Leyden jar 
intercalated in the circuit, the colour of the luminous dis- 
charge chan<;es from red to a rich steel blue, and the 
spedfum shows an almost entirely different set of lines. 
The two spedlra, called for brevity red and blue, are shown 
on the large map, the upper spedrum being that of 
" blue " argon, and the lower one that of " red " argon. 
It is not easy to obtain the blue colour and spedtrum 
Entirely free from the red. The red is easily got by using 
a large coil) adlualed with a current of 3 ampires and 
6 volts. There is then no tendency for it to turn blue. 

The blue colour may be obtained with the same coil by 
aduating it with a current of 3*84 amperes and 11 volts, 
intercalating a jar of 50 square inches surface. The 
make-and- break must be screwed up so as to vibrate as 
rapidly as possible. With the small coil a very good blue 



* Prom the Philosophical Transactiom of the Royal Society, vol. 
clxxxvi. (1895), Am pp. 243.251. 

f Roy. Soc. Proc., vol. I , p. 88, June, i8pr. 

t The coil used has about sixty miles of secondary wire, and when 
fully charged gives a torrent of sparks 24 inches long. The smaller 
coil gives six-inch sparks when worked with six half-pint Grove cells. 



colour can be obtained by using three Grove cells and a 
Leyden jar of Z20 square; inches surface, and a very 
rapid make-and-break. It appears that an ele&ro- 
motive force of 27,600 volts is required to bring out the 
red, and a higher E.M.F. and a very hot spark for the 
blue. It is possible so to adjust the pressure of gas in the 
tube that a very slight alteration of the strength of the 
current will cause the colour to change from red to blue, 
and vict versa, I have occasionally had an argon tube in 
so sensitive a state that with the commutator turned one 
way the colour was red, and the other way blue. Indoc> 
tion coils aduated by a continuous current are never sym- 
metrical as regards the polarity of the induced current, 
and any little irregularity in the metallic terminals of the 
vacuum tube also ads as a valve. The red glow is pro- 
duced by the positive spark, and the blue by the negative 
spark. 

I have taken photographs of the two spedra of argon 
partly superposed. In this way their dissimilarity is 
readily seen.* In the spedrum of the blue glow I have 
counted zxg lines, and in that of the red glow 80 lines, 
making 199 in all; of these, 26 appear to be cooamon 
to both spedra. 

I have said that the residual nitrogen is removed by 
sparking the tube for some time when platinum terminals 
are sealed in. This is not the only way of purifying the 
argon. By the kindness of Professor Ramsay I was 
allowed to take some vacuum tubes to bis laboratory and 
there exhaust and fill them with some of bis purest argon. 
On this occasion I simultaneously filled, exhausted, and 
sealed off two Pliicker tubes, one having platinum and 
the other aluminium terminals. On testing the gas 
immediately after they were sealed off, each tube showed 
the argon spedtrum, contaminated by a trace of nitrogen 
bands. The next day the tube with platinum terminals 
was unchanged, but that having aluminium terminals 
showed the pure spedlrum of argon, the faint nitrogen 
bands having entirely disappeared during the night. 
After an hour's current and a few days' rest the tube with 
platinum terminals likewise gave a pure argon spedrum. 
When a mixture of argon with a very little nitrogen is 
submitted to the induced current in a tube made otfused 
and blown quartz, without inside metallic terminals, the 
nitrogen bands do not disappear from the argon spe^rum, 
but the spedra of argon and nitrogen continue to be seen 
simultaneously. 

A vacuum tube was filled with argon and kept on the 
pump while observations were made on the spedrum 
of the ^as as exhaustion proceeded. The large coil was 
used with a current of 8*84 amperes and ix volts ; no jar 
being interposed. At a pressure of 3 m.m. the spedrum 
was that of the pure red glow. This persisted as the 
exhaustion rose, until at a pressure of about half a m.m. 
flashes of blue light made their appearance. At a quarter 
of a m.m. the colour of the ignited gas was pure blue, 
and the spedrum showed no trace of the red glow. 

A striking instance of a change of spedrum from nitro- 
gen to argon was shown in a tube filled with argon 
kindly sent me by Lord Rayleigh. It had been prepared 
from the atmosphere by sparking, and it was considered 
to contain about 3 per cent of nitrogen. Thfs argon was 
passed into an exhausted tube and then rarefied to m 
pressure of 75 m.m. and kept on the pump. At this 
pressure the nitrogen conduded all the indudlon cur- 
rent, the spedrum showing nothing but the nitro- 
gen bands. The pump was slowly kept going, and 
spedrum observations were continuously taken. When 
the pressure fell to about 3 m.m. a change came over the 
spedrum, the nitrogen bands disappeared, and the 
spedrum of argon took its place ; the only contamina- 
tion being a little aqueous vapour, due to my not having 
sufficiently dried the gas. I took photographs of th^ 
spedrum given by this tube in the two stages, one show- 



♦ Photographs of the different speftra of argon, and other gaseous 
spedra for comparison, were prujedted on the screen. 



CasMicALfltwrii 

_ Aug. 9, 1895^ f 

ing the pure nitrogen bands and the other the argon 
lines, each being compared with the spe^rum of argon 
prepared by Professor Ramsay. Observations have shown 
that the spe^ra given by argon, obtained by the sparking 
method of Lord Rayleigh and by the magnesium method 
of Prof. Ramsay from the atmosphere, are identical. 

U was of interest to see how little argon could be 
dete&ed in admixture with nitrogen by combined pumping 
aniil passage of the current. Some argon prepared by 
myselA* having 60 to 70 per cent of nitrigen with it, was 
put into a small tube furnished with large platinum 
terminals. Exhaustion was carried to 3 m.m., and the 
tube was then sealed off. The spark from the large coil 
aduated with a current of 3*84 amperes and 11 volts was 
then put on, and the spedrum examined continuously. 
At first it showed only the nitrogen bands. In about half 
an hour the nitrogen began to fade and the ar^on lines 
appear, and in a few minutes later the tube was just short 
of non-conduAing, the colour of the gas was rich steel- 
blue, and the spedruro was that of the blue argon glow. 
Here the small diameter of the bulbs of the tube and the 
large platini^m v^ires facilitated much spattering or 
** eledrical evaporation '' of the platinum. The pres- 
sure also was the one most suitable for that phenome- 
non. To this I attribute the rapid occlusion of the 
residual nitrogen. 

An experiment was now made to see if the small 
quantity of argon normally present in the atmosphere 
could be deteded without previous concentration. Nitro- 
gen was prepared from the atmosphere by burning 
phosphorus, and was purified in the usual manner. This 
gas, well dried over phosphoric anhydride, was passed 
into a vacuum tube, the air washed out by two fillings 
and exhaustions, and the tube was finally sealed off at a 

greisure of 52 m.m. It was used for photographing the 
and spedrum of nitrogen on several occasions, and alto- 
gether it was exposed to the indudion current from the 
large coil lor eight hours before any change was noticed. 
The last time I used it for photographing the nitrogen 
spedrum difficulty was experienced in getting the spark to 

J»as8, so I increased the current and intercalated a small 
ar. The colour immediately changed from the reddish 
yellow of nitrogen to the blue of argon, and on applying 
the spedroscope the lines of argon shone out with scarcely 
any admixture of nitrogen bands. With great difficulty 
and by employing a veiy small jar I was able to take one 
photograph of this changed spedrum and compare it with 
the spedrum of argon from Professor Ramsay, both being 
taken on the same plate, but the tube soon became non- 
conduding, and I could not then force a spark through, 
except by employing a dangerously large current. When- 
ever a flash passed it was of a deep blue colour. Assuming 
that the atmosphere contains i per cent of argon, the 
3 m.m. of nitrogen originally in the tube would contain 
0*03 m.m. of argon. After the nitrogen had been oc- 
cluded by the spa^ttered platinum, this pressure of argon 
would be near the point of non-condudion. 

In all cases when argon has been obtained in this 
manner the spedrum has been that of the blue-blowing 
gas. Very little of the red rays can be seen. The change 
from red to blue is chiefly dependent on the strength and 
beat oi the spark : partly also on the degree of exhaustion. 
Nitrogen, when present, conduds the current easiest. As 
the exhaustion increases and the condudivity of the nitro- 
gen diminishes, that of the red-glowing argon rises, until 
at a pressure of about 3 m.m. its condudivity is at the 
greatest and the luminosity is best. Beyond that point the 
condudivity of the red form seems to get less, and that of 



Spectra oj A rgon. 



67 



the blue form to increase, till the vacuum approaches a 
fradion of a m.m., when further pumping soon renders it 
non-cooduding. It is not improbable, and I understand 
that independent observations have already led both the 
discoverers to the same conclusion — that the gas argon is 
not a simple body, but is a mixture of at least two ele- 
ments, one of which glows red and the other blue, each 
having its distindive spedrum. The theory that it is a 
simple body has, however, support from the analogy of 
other gases. Thus, nitrogen has two distind spedra, 
one or the other being produced by varying the pressure 
and intensity of the spark. I have made vacuum tubes 
containing rarefied nitrogen which show either the fluted 
band or the sharp line spedrum by simply turning the 
screw of the make-and-break: exadly as the two spedra 
of argon can be changed from one to the other. 

The disappearance of the red glow and the appearance 
of the blue glow in argon as the exhaustion increases also 
resembles the disappearance of the red line of hydrogen 
when exhaustion is raised to a high point. Pliicker, who 
was the first to observe this occurrence, says* : ** When 
RuhmkorfiTs small indudion coil was discharged through 
a spedral tube enclosing hydrogen, which was gradually 
rarefied to the highest tenuity to be reached by oceans of 
Geissler*s exhauster, finally the beautiful red colour of 
the ignited gas became fainter, and passed gradually into 
an undetermined violet. When analysed by the prism, 
Ha (the red, C, line) disappeared, while H/3 (the green, 
F, line), though fainter, remained well defined. Accord- 
ingly* light o^ A greater length of wave was the first 
extinguished.** 

The line spedrum of nitrogen is not nearly so 
striking in brilliancy, number, or sharpness of lines as are 
those of argon, and careful scrutiny fails to show more 
than one or two apparent coincidences between lines in 
the two spedra. Between the spedra of argon and 
the band spedrum of nitrogen there are two or three 
close approximations of lines, but a projedion on the 
screen of a magnified image of the two spedra partly 
superposed shows that two at least of these are not 
real coincidences. 

I have looked for indications of lines in the argoa 
spedra corresponding to the corona line at 531*7, the 
aurora line at 557*1, and the helium line at 587*5, but 
have failed to deted any line of argon sufficiently near 
these positions to fall within the limits of experimental 
error. 

I have found no other spedrum-giving gas or vapour 
yield spedra at all like those of argon, and the apparent 
coincidences in some of the lines, which, on one or two 
occasions are noticed, have been very few, and would 
probably disappear on using a higher dispersion. Having 
once obtained a tube of argon giving the pure spedra, I 
can make no alteration in it except that which takes 
place on varying the spark or increasing the exhaustion, 
when the two spedra change from one to the other. As 
far, therefore, as spedrum work can decide, the verdid 
must be that Lord Rayleigh and Professor Ramsay have 
added one, if not two, members to the family of ele- 
mentary bodies. 



* When a carrent of 65 volts and 15 amp^rei altematiog 130 times 
A second it pMsed through the primary of my Uree ctfll, an arcbiog 
flame, coositting of baming nitrogen, itauea from each of the 
Mcondary polea, meeting in the middle. When once aurted the 
poiet can be drawn asunder, till the flame bridgea acrosi aia m.m. 
When the terminali are more than 46 m.m. apart the Hame will not 
atrike acroaa. By enclosing this flame in a reservoir over alkaline 
water, and feeding it with air and oxygen, 1 can burn up a litre of air 
an botir. 



BLUff. 



Red. 



Wave-length. Intensity. Wave-length. 
7646 


Intensity. 
2 


7506 


4 


7377 
726-3 

70564 


3 

a 
10 

9 

2 


675'4 
666*4 


6 
6 



* " On the Spears of Ignited Gases and Vapours," by Drs. Pliicker 
and Hiltorf, Pktl. Tram., Part 1, civ., p. 21. 



e:8 




Red. 

1 





Spectra oj Argon. 








fCKBMtCALMBWt, 
1 Ang. 9, 1895. 


Blui 

* t 


. 




Blus. 


Rbo. 






Wave-length. 


Intensity. 


Wave-length. 


Intentitf. 


Wave-length. 


Intensity. 


Wave.length. 


Intensity. 


662-8 


4 








426*60 


6 


426*60 


4 


Coincident. 






640-7 


9 




425-95 


8 


425-95 


9 


^Coincident. 






6377 


3 




425-15 


3 


425-15 


3 


Coincident. 






630*3 


4 




422*85 


6 












628*1 


3 




420* XO 


XO 


430* xo 


xo 


Coincident. 


623*2 


4 








4x9-80 


9 


4x9*80 


9 


Coincident 






62X*0 


6 




419*15 


9 


4X9*X5 


9 


Coincident. 


617-3 


6 


6x7*3 


6 


Coincident. 


418-30 


8 


4x830 


8 


Coincident. 






6X4*3 


3 




416-45 


8 


416-45 


4 


Coincident. 


6X2*0 


6 


609-9 
605*6 
604-5 


4 
3 

3 




415-95 

4I3-X5 
4x0*50 


xo 

3 
8 


415*95 
4x5*65 


xo 
6 


Coincident. 


603-8 


8 


603-8 


8 


Coincident. 


407-25 


8 












593*5 


X 




404*40 


8 


404-40 


9 


Coincident. 


592*6 


4 


592-6 
590-9 

IS? 


4. 
6 
6 

4 


Coincident, ' 


403-30 
40X-30 

397-85 
39678 


X 

8 

X 

3 












583-4 


3 




394-85 


9 


394-85 


xo 


Coincident. 






580-3 


X 




394*35 


3 












577-1 


2 




393-18 


3 












574-6 


6 




392-85 


9 












5683 


3 




392-75 


3 












565*1 


9 




391-50 


X 












561*0 


9 








390*45 


8 








556-7 


3 




389-20 


5 












555-7 


XO 




357'55 


3 












552-0 


X 




387-X8 


3 












550-1 


3 




38685 


8 












549-65 


8 




385-15 


xo 












545-6 


6 




384-55 


X 












544-4 


3 




38355 


3 


383*55 


3 


Coincident. 






542-1 


4 




382*75 


3 












5258 


6 




380-95 


4 












522-3 


7 




380*35 


X 












518-58 


XO 




379*95 


X 












5x6-5 


9 




37808 


9 








5x4-0 


xo 












377*15 


X 




506*5 


10 


506-5 


4 


Coincident. 


37705 


3 








50X-2 


3 


501-3 


4 


Coincident. 


37660 


8 








500-7 


9 








37385 
372*98 


3 








496-55 


9 


496-55 


4 


Coincident. 


xo 








493*8 


10 


493-8 


3 


Coincident. 


371-80 


4 








487*9 


10 


487-9 


4 


Coincident. 






363*25 


3 




484-75 


I 








363-17 


X 








48050 


7 












362-37 
362-28 


X 




476*30 


I 












X 




473-45 
472-66 


6 








361-75 


3 








2 








360*50 


3 


360*50 


5 


Coinctdeot. 






470* X2 


8 




35870 


xo 








46565 


5 


462*95 


5 




35803 
357*50 


9 
9 








46080 


8 


459*45 


3 




35665 
356-40 


3 
3 


356*65 


4 


Coincident. 


45869 


6 












35628 


X 




457*95 


6 








356*00 


3 








454*35 


7 








355*82 


7 












451-40 


2 




355*45 


4 


355*45 


6 


Coincident. 


45095 


8 


450-95 


9 


Coincident. 


354*75 


4 








447-83 


6 








354*45 


7 








442-65 


10 








353*43 


4 








44225 


xo 








35205 


3 








439*95 


10 








351-92 


4 








43765 


9 








35**35 


6 








43690 


9 








35088 


4 








434-85 


xo 


434-50 


5 




349-00 
347*57 


xo 
7 








433-35 


9 


433*35 
43005 


9 

9 


Coincident. 


345*35 
338-80 


X 

X 








42990 


9 








309*27 


5 








42770 


3 








308*48 


4 








42720 


7 


42720 


8 


Coincident. 


30647 


2 









;i 



Blub. 
Wav^lcogtb. louwitj. 



Chromates of the Rare Eartlis : Chromates of Strontium. 



69 



30427 
299*82 
29786 

294*27 
292*96 
283*02 

279'44 
a73'45 
27072 
269*30 
266*12 
265*26 
262*95 
257*12 
256*07 
248*49 

24385 
224*66 



3 

I 

z 
2 

X 

I 

2 
2 

0*5 

z 
2 

3 

I 
2 
z 
z 
2 
3 



IZ9 lines in the " Blue " spedram. 
80 lines in the ** Red *' spedram. 

Z99 total lines. 
26 lines common to the two spedra. 



CHROMATES OF THE RARE EARTHS: 

CHROMATES OF THORIUM. 

Bf CHASB PALMER. 

BBLimviNO that a study of the adion of an acid of feeble 
energy upon the weak bases of the tin group— or Fourth 
Ofoup of Mendeleeffs Periodic System — would throw new 
light upon this interesting family of elements, I have 
ttDdertaJcen a comparative study of the adion of chromic 
mdd upon the oxides of the rarer metals of this group, and 
of the condud of their salts towards the alkaline chro- 



The chromates of the rare elements of this group have 
hitherto received but little attention from chemists. The 
earliest allusion to a chromate of a rare earth was made in 
1863 by J. J. Chydenius ('* Thorerde und deren Verbind* 
QOgeo," Ann, dir Pkfs, Pogg.t cxix., 43). This author 
obaervei that thorium hydroxide is soluble in chromic 
acid. He states that from the resulting solution, evapo- 
rated over sulphuric acid, he obtained normal thorium 
chromate as a soluble salt containing eight molecules of 
water of crystallisation. Chydenius further states that 
potassium dichromate produces no precipitate when 
added to a solution of thorium chloride, until after the 
mixture is neutralised with ammonia, whereby a basic 
•alt of thorium is thrown down. The only other allusion 
to a chromate of a rare metal of the Fourth group, in the 
literature accessible to me, is made by Pattison and 
Clarice fCBSM. News, xvi., 259). These chemists ob- 
served that by heating the residue from an evaporated 
solution of the hydroxides of cerium, lanthanum, and 
didyminm in chromic acid, the cerium compound was 
rendered insoluble ; but there is no evidence that they de- 
termined the composition of the insoluble produd. 

Thorium was chosen as the first element for the present 
research on account of the highly developed basic pro- 
perties of its oxide. Contrary to the observations of 
Chydenius, I have found, not only that a difficultly soluble 
salty having the composition of normal thorium chromate, 
separates spontaneously from a solution of thorium 
hydroxide in chromic acid, but also that the same com- 
poood is precipitated by potassium dichromate from 
thorium nitrate without the aid of a neutralising alkali. 
I have also found that potassium chromate produces the 
same compound indiredly from a soluble thorium salt. 

Thorium Hydroxid* and Chromic i4ci<f.— Pure freshly 



precipitated thorium hydroxidej was added in portions 
to a solution of pure chromium trioxide in water. The 
quantity of the trioxide was slightly in excess of the 
amount required to form the normal chromate. The hy- 
droxide was quickly dissolved at first, but afterwards the 
acid attacked it more sluggishly. A flocculent orange 
precipitate soon appeared, and finally settled as a fine 
powder. Under the microscope this produd shows a 
crystalline strudure. The formation of the orange pre- 
cipitate takes place more quickly at 90^ C. than at the 
ordinary temperature. 

Dried at 120" C. to constant weight the produd was 
analysed : — 

0*2016 grm. substance at 180* lost 0*0072 grm. HsO 
and gave o*tzz4 grm. ThOa and 0*0626 grm. CrtO|. 



H2O 
Th . 
Cr 



Calcalated for Th(CrO«VHtO. 

373 

, .• .. 4805 
2I*7Z 



Found. 

357 
4855 

2Z*29 



Thorium Chromatifrom Chromic Acid Solution, — Pore 
freshly-precipitated thorium hydroxide, in small portions 
at a time, was stirred in a cold solution of chromic acid 
as long as it was taken up. At the first appearance of 
the orange precipitate, the latter was filtered off, and the 
solution evaporated over sulphuric acid in vacuo. From 
the concentrated solution thorium chromate separated 
out in orange-coloured scales containing two molecules of 
water of crystallisation and one molecule of water of con- 
stitution. 

Dried to constant weight over sulphuric acid the salt 
was analysed. 

I. 0*215 grm. substance lost o*oz48 grm. H^O at Z2o° ; 
at iSo*" it lost 0*007 grm. HaO additional, and gaveo*zi04 
grm. ThOa and 0*0631 grm. CraOj. 

H. 0*2x55 grm. substance lost 0*0x5 grm. HaO at Z20^ ; 
at 180° it lost 0*0068 grm. HaO additional, and gave 0*1 ti 
grm. ThOa and 0*0622 grm. CraO^. 

Found. 





Calculated for 








Th(CrO«),.3H.O. 


I. 


II. 


2HaO .« 


690 


6*88 


6*96 


HaO .. 


-. 346 


3-25 


3-15 


Th •• 


.* 4471 


45" 


45*26 


Cr 


• . 20-20 


20*X2 


Z970 



Thorium Nitrate and Potassium Dichromate,'-' On 
mixing the boiling solutions of these salts in the propor- 
tion of one molecule of the nitrate to two molecules of the 
dichromate, hydrated thorium chromate was precipitated 
at once as a fine orange powder. In this way 78 per 
cent of the theoretical yield was obtained. 

0*1986 grm. substance, dried at I20^ lost 0*0073 grm. 
HaO at iSo'^ and gave 0*1095 grm. ThOa and 0*0068 grm. 
CraOj. 

Found. 

HaO 367 

Th 4835 

Cr 2X*34 

When the cold solutions of thorium nitrate and potas- 
sium dichromate were mixed no immediate precipitation 
occurred, but in a short time a precipitate began to form. 
After standing twenty-four hours the orange precipitate 
that bad formed meanwhile was filtered off, washed, and 
dried at X2o^ 

o*z8x7 grm. substance lost 0*0064 grm. HaO at z8o^ 
and gave o*xoo8 grm. ThOa and o*o5(^ grm. CraO^. 



HaO 
Th., 
Cr .. 



FODOd. 

3-52 
4875 

21*47 



The filtrate from this precipitate was heated to 90^. 
At 60"^ a second precipitation of the thorium chromate 



The Wet Assay for Copper. 



fCRBMIC4L *^BWS, 

I Aus. 9, 1895. 



occurred. The first yield was 65 per cent, and 14 per 
cent additional was obtained by heating the filtrate. The 
total yield (79 per cent) closely corresponds with the yield 
obtained by precipitating the compound at once from a 
boiling solution. 

The mother-liquor from the second precipitate was re* 
duced to small volume, but no further precipitation oc- 
curred. Bv evaporating it to dryness a very soluble crys- 
talline produd was left, but it couM not be isolated for 
examination. 

ThQrium NitraU and Potassium Chromati, — There are 
two stages in the formation of hydrated thorium chromate 
from thorium nitrate and potassium chromate. When a 
solution of tliorium nitrate is treated with a solution of 
potassium chromate (one molecule of the former to three 
molecules of the latter), the precipitate, which at once 
forms, dissolves immediately until the mixture is com- 
plete. Then a dense golden yellow precipitate separates 
from the solution. The liquid meanwhile becomes red, 
owing to the formation of potassium dichromate. By 
promptly removing the yellow precipitate from conta^ 
with the fluid it was found, on analysis, to be basic 
thorium chromate. 

0*2367 arm. substance dried at 100° gave 0*1635 grm. 
ThOs and 0*0459 grm. CraOj. 



Th 
Cr 



CalcaUted for Th(OH)sCrO«. 
.. .. 6o*66 
.. .. 1370 



Pouod. 
60*70 
1329 



. If the basic thorium chromate be allowed to remain in 
contaft with the supernatant liquid, it is gradually changed 
into the orange precipitate, which, upon analysis, proved 
itself to be the same hydrated thorium chromate already 
described. During this transformation the red liquid is 
changed to the bright yellow colour of potassium chro- 
mate. 
Analysis of the final produd dried at 120^: — 
0*2136 grm. substance at 180* lost o*oo8x grm. HaO and 
gave 0*1175 grm. ThOi and 0*0678 grm. CrjOj. 



HiO 
Th.. 
Cr .. 



Foand. 

379 
48-34 
2177 



The complete reaftion may be expressed by the two 
equations : — 
J. Th(N03)44-3KaCr04-|-HaO- 

=Th(OH)aCr04+KaCra07+4KN03. 
2. Th(OH)aCr044-KaCra07=-Th(Cr04)a.HaO + KaCr04. 

The hydrated thorium chromate always has a full 
orange colour, which it does not lose even after prolonged 
heating at 130®. The colour of the anhydrous salt is 
ochrcous yellow. At 22^ i part of the salt is soluble in 
284 parts of water. It is readily soluble in hydrochloric 
acid and in ammonium carbonate. At a dull red heat it 
is decomposed into thorium dioxide and chromic oxide. 
Heated in a platinum crucible over a Bunsen lamp the 
substance lost 10*41 per cent in weight. For the loss of 
.three oxygen atoms to form ThOa and CraOj the required 
loss in weight is 10*32 per cent. 

Constitution of the Orangi Chromate — It is noteworthy 
that the orange chromate of thorium always contains one 
molecule of firmly bound water, whether the substance be 
formed by slow crystallisation from a chromic acid solu- 
tion, or by precipitation from a soluble salt, or formed 
from the insoluble basic chromate. The substance may 
be regarded simply as hydrated normal thorium chromate, 
Th(Cr04)aHaO, or it may be a basic dichromate of 
thorium having the constitution expressed by the formula 

^**^(OH)a • 
Before expressing an opinion as to the more probable 
co nstitut i on of the orange chromate, I shall attempt to 



gather more knowledge of these chromates and of the 
compounds of chromic acid with the related elements. 

Zirconium hydroxide is attacked by chromic acid less 
readily than iv thorium hydroxide. It can be completely 
dissolved in an excess of the acid. A yellow precipitate 
was obtained by boiling this solution. From an analysis, 
the produA appears to oe a basic salt. 

A similar yellow precipitate is obtained by the adion of 
potassium dichromate on zirconium chloride. The pre- 
cipitate, dried over sulphuric acid, gave 41*24 per cent Zr 
and 16*38 per cent Cr. It is probably a basic salt. 

I intend to make a thorough study of the chromates of 
zirconium and of the other elements of the Fourth Group. 

I wish to express here my hearty thanks to Professor 
Edgar P. Smith, through whose generous hospitality I 
have enjoyed the facilities of the John Harrison Chemical 
Laboratory of the University of Pennsylvania, whc^e the 
work described in this paper has been dont.^ A mnican> 
Chemical Journal^ xvii.. No. 5. 



THE WET ASSAY FOR COPPER. 
By R. S. DULIN. 

It seems difficult for the metallurgical chemists of this 
country to settle upon a uniform method for the rapid de- 
termination of copper. We should have a standard 
method, applicable for all commercial work, which would 
be fairly accurate under as many possible varying condi- 
tions, so that results obtained from the same ore, hy 
different chemists, should be substantially uniform. For 
about nine months past I have been engaged npoo an 
extended series of experiments, having for their objeA a 
determination of the chief causes for variation and error 
in the methods most generally employed, and for the pur- 
pose of finding a modification of common methods which 
would be an improvement upon those now used. At the 
same time I have made myself conversant with much of 
the current literature upon the subject, and the obeerva- 
tions herein offered, while based upon my individual es- 
perimenu, are corroborated, in most part, by the published 
results of others. 

There are at present three well-recognised methods 
employed in the United States for the determination of 
copper. Each method has its own advocates, and it is 
perfedly fair to say that either method, in the hands of a 
skilled chemist, thoroughly understanding the reaAions of 
the methods, working with all due care, will yield sub- 
stantially the same results. The methods referred to 
are: — 

I. The cyanide method. 2. The iodide. 3. The 
eledrolytic. A colorimetric method is also employed for 
the determination of copper when the percentages fall 
below 2 per cent. I have made no particular study of 
this method, and, as it is only employed in special cases, 
I shall make no further reference to it. 

The cyanide method depends upon the fad that, wheo 
a solution of potassium cyanide is run into an arnmont* 
acal solution of copper, the blue colour is discharf^ed. 
The readion is as follows : — 

(NH4)a(NH3)a,CuO(N03)a+4KCN+3HaO= 

«KaCu(CN)4-|.2KNOj+4NH40H. 

This method is fullv described in Forman's " Manual 
of Pradical Assaying.'^ The following precautions should 
always be carefully observed :— i. The bulk of the liquid 
titrated should always be uniform ; by inattention to this 
an error of from 2 to 3 per cent is possible. 2. The so- 
lution should alwa3rs be cooled to the temperature of the 
laboratory before titrating, otherwise an error of about 
3 per cent is possible. 3. The amount of ammonia 
added should be nearly constant, otherwise the possible 
error may amount to as much as 5 per cent, or even 



OltlMICALNBVt,1 



The Wet Assay for Copper. 



71 



These precautions are general, and mast always be 
carefully observed in every modification which may be 
made in the method. In the ordinary modification of the 
method, ferric hydroxide is almost certain to be precipi- 
tated upon the addition of the ammonium hydroxide. If 
the amount be small, no error is apt to occur, but it 
should always be filtered off. If the amount be large, it 
is not easy to wash out all of the copper salt, thereby 
causing lower results, unless large quantities of wash- 
water are employed, thus increasing and varying the 
bulk. The error arising from increased bulk may be ob- 
viated, by taking, after mixing, an aliquot part of the 
solution ; if the solution be not thereby made very dilute 
the error is so slight that it may be negleAed. If salts 
of manganese are present the end readion cannot be 
determined, owing to the liquid first turning green, finally 
black. The presence of large quantities of calcium, I 
found, confused the end readion, causing error of im- 
portance. Experiments made showed that magnesia did 
not interfere, and the presence of antimony and arsenic 
was found to cause no sensible variations. 

Zinc, which is almost certain to be present in varying 
amount, is a possible source of great error. The fol- 
lowing results were obtained from a large number of 
carefully conduced experiments. Only the averages are 
given, and they are substantially the same as the 
extremes. In these experiments the bulk of the liquid 
varied from 25 to as much as 50 c.c, thereby causing a 
slight error, for which no corredion has been made. 
This error would not substantially change the results. 
Careful attention was paid to the precautions previously 
enumerated. 



Weight of 


Weight of 


Cyanide 




copper. 


zinc. 


used. 


Increase. 


0-05 


O'OO 


Io*4 C.C. 


— 


<ro$ 


O'OI 


iro „ 


0^6 C.C. 


005 


0*02 


"7 .. 


1-3 .. 


005 


0-03 


12-3 M 


1*9 .. 


005 


0'04 


12*9 .. 


2*5 H 


0*05 


0-05 


14-0 „ 


36 „ 


0*05 


o*o6 


161 „ 


57 .. 


0-05 


0*07 


i8-9 n 


8-5 n 


0*05 


0'o8 


21-6 „ 


11-2 „ 


0*05 


o'og 


243 n 


13*9 .» 



These results show that there is a gradual increase o 
about six-tenths c.c. in the amount of the cyanide solu* 
iion required, until the amount of zinc present nearly 
equals the amount of copper, when the increase becomes 
variable, until the amount of zinc becomes greater than 
the amount of copper to the extent of 20 per cent, when 
the increase, though larger, about 2^0 c.c, again be- 
comes regular. 

The effcds of cadmium are similar, as shown by the 
following results, which are also the averages of a large 
number of experiments, in which the extremes are farther 
removed from the mean than was found with zinc. As 
in the preceding experiments, the precautions previously 
enumerated were very carefully observed, except in the 
case of bulk, in which the variations were identically the 
same as with the experiments with zinc. 

Weight of Weight of 
copper. cidmiom. 

0*05 0*00 

0*05 0*0 X 

0*05 0*02 

0*05 0'03 

0*05 0x4 

o'05 0*05 

0*05 0*06 

0*05 0*07 

0*05 0*08 

These results show that there is a gradually accumu* 

latiog increase in the consumption of cyanide due to the 

presence of cadmium. As cadmium is a constituent 



Cyanide 




oied. 


Increase. 


10*4 c.c 


— 


10-6 „ 


0'2 C.C 


10-8 „ 


04 .. 


in „ 


07 M 


iz'6 „ 


1*2 „ 


120 „ 


1-6 .. 


I2'4 » 


2-0 „ 


135 .. 


3-1 M 


14*5 .. 


41 .» 



usually found associated with copper, it must be removed 
if reliable results be required. Silver also interferes, but 
in a regular way. If the amount of silver be known, by 
previous assay, it is best allowed for by calculation. 

The following modification of the cyanide method has 
been thoroughly tested, under the immediate superviiion 
of Prof. Seamon, and it is recommended as giving results 
equal in value to those obtained by the eledrolytic 
method. 

The ore is treated according to the method described 
on page 161 of Purman's *' Manual of Assaying.'* In 
this way a solution of the copper salt is obtained, prac- 
tically free from lead and silver. This solution is boiled 
with strips of aluminum foil, resulting in the complete 
precipitation of the copper together with any silver which 
may remain in the solution, which is always so small as 
to be negligible, as I have demonstrated by a number of 
experiments upon different ores. If cadmium be present 
it IS only partially precipitated, beginning after the copper 
is thrown down. If care be taken to stop the boiling, 
immediately after the copper is precipitated, which can be 
determined with constant pra&ice by the eye, the amount 
of cadmium precipitated is so small as not to cause 
sensible error. The liquid is decanted from off the 
aluminum foil and copper, quickly washed several times 
with hot water, care being taken not to wash away any 
particles of the copper ; 3 c.c. of nitric acid are then added 
to the flask, and boiled to dissolve the copper ; the solu* 
tion is then treated with ammonium hydroxide as in 
the usual way, and titration is made with the usual solu- 
tion of cyanide. 

This method has been very carefoUy tested, and the 
results were so satisfa^ry, and nearly uniform, that I 
recommend it as being as accurate as the ele^rolytic 
method, under the conditions in which the latter is usually 
employed. 

The iodide method is most commonly employed in the 
Lake Superior Distridt and in foreign countries, where it 
is regarded with much favour. Many chemists regard it 
as more accurate than the cyanide or eleArolytic methods, 
and there is no doubt from my experiments that it is 
more accurate than the ordinary modification of the 
cyanide and equal to that of the eledrolytic. The method 
depends upon the following readions : — 

2CuS04-|-4KIaCu2la+2l+2KaS04 
2NaaSt03+2l»2NaI-|-Na3S406. 

The best results are obtained when the copper is preci- 
pitated with aluminum foil, as previously described under 
the cyanide method. The method is fully described in 
Furman*s ** Manual of Assaying," and I only desire to 
call attention to the necessity for attending to the fol* 
lowing precautions :~ 

I. The presence of iron in about equal amounts with 
the copper requires more ** hypo,** increasing the amount 
of copper to the extent of 2 to 3 per cent. 2. The solu- 
tion should be titrated cold. 3. The presence of large 
amounts of alkaline salts, particularly sodium sulphate, 
decreases the amount of copper. 4. The presence of 
bismuth clouds the end reaAtons. My experience with 
the modification of this method, in which the copper is 
first precipitated with aluminum foil, convinces me that 
with this change the results are as accurate as those ob- 
tained with the modified cyanide method ; but it is not 
so rapid, owing to the time lost at various stages : this is 
an important fador in the adoption of any method for 
metallurgical work, when thirty and forty assays must be 
completed every day. The method is a little more diffi- 
cult to manipulate than the cyanide method. 

The eledrolytic method is perhaps the most highly 
favoiued in this country. It has the reputation for greatest 
' accuracy. It requires more time than either of the other ; 
but since it is easy to regulate the work, so that the bat- 
tery will precipitate during the night, this is not of so 
much importance. In regular routine work, after solution 
is effeded, the copper should bo precipitated with hydro* 



72 



Revision of the Atomic Weight of Strontium. 



jCBBMICAL NbW», 

I Aug, 9, 1895. 



gen sulphide, othenvise many interfering metals are apt 
to be present and deposited with the copper. I have 
found that errors from this source are largely, if not en- 
tirely, eliminated, if deposition be made from a solution 
containing a large amount of nitric acid. My best results 
were obtained when I added 20 c.c. of strong nitric 
to about 150 c.c. of solution. This holds up the other 
metals, but a stronger current is required to precipitate 
all of the copper, and more attention must be paid to 
proper and rapid manipulation after precipitation. This 
method is much improved by previously precipitating the 
copper from its solution by boiling with aluminum foil 
and then re-dissolving the copper in nitric acid. The 
following results, obtained from the same sample, care- 
fully prepared, obtained by the three methods, furnish a 
fair idea of the relative values of the several methods. 

A copper matte, containing 20*15 per cent of copper, as 
determined by a large number of analyses, made by seve- 
ral different assayers and by different methods, was run 
by each method. The amount of copper in the second 
matte, determined from the same data, was found to be 
28 per cent, while the per cent of copper in the ore 
was 30*18. 

The results obtained by the cyanide method were 
respe^ively 20*15, 27*95, and 30*20 per cent. The copper 
was first precipitated with the aluminum foil. The same 
substances, with the iodide method, first precipitating 
with aluminum foil) gave, respedkively, 20*25, 28*35, ^"^ 
36*3 per cent. By the eledirolytic method the same 
substances gave, respe^ively, 20*045, 28*15, and 30*05 
per cent. 

These results justify the statement that the iodide 
method, with the aluminum modification, gives results 
usually one-tenth to three-tenths per cent too high, 
while the elearolytic method is too high or too low, 
according to the amount of metallic substances present 
precipitable by the eledlric current; and the cyanide 
method gives results which are pradically corred. — 
youmal of the American Chemical Society, xvii., p. 346. 



A REVISION OF THE ATOMIC WEIGHT OF 

STRONTIUM. 

First Paper : The Analysis of Strontic Bromide.* 

By THEODORE WILLIAM RICHARDS. 
(Condaded from p. 56). 

Ratio of Argefttic to Strontic Bromide, 
In many of the preceding determinations the bromide of 
silver resulting from the decomposition was weighed. 





Ratio 


0/ Strontic and Argentic 
First Series, 


Bromides 




No. 
of 

Anal. 


No. 

of 

Spec. 


Weight 

of 
Strontic 
Bromide 

Uken. 


Weight 
of fased 
Argentic 
Bromide 
found. 


Ratio 

SrBr, , 
2Agbr • 


At. wt. 

of 
Strontium. 


J3» 
14- 
15. 


I. 

II. 

111. 


Grmi. 
r6o86 
1*8817 
4*5681 

8*0584 


Grma. 

2*4415 
2*8561 

6*9337 
12*2313 


65*886 
65*884 
65-883 

65*8834 


87669 
87*662 
87*657 




87660 


16. 

17- 
18. 

19. 


III. 

III. 

III. 

V. 


Second Series. 
1*49962 2*27625 
2*41225 3*66140 
2*56153 3*88776 
6 15663 9-34497 


65*881 
65-883 
65887 
65882 





12*63003 19*17038 65-883 87659 

^ CoDtributioos from the Chemical Laboratory of Harvard Col- 
lc«e. From the Proceedings of the American Academy. 



In every case a slight excess of silver nitrate was 
added, to render the argentic bromide wholly insoluble in 
the filtrate. The very slight amount which may have 
been dissolved by the wash water during its brief contaA 
with the precipitate was not considered. The precipitate 
was colleded upon a Gooch crucible; and the traces (0*04 
to 0*2 m.grm.) of asbestos carried through were colle^ed 
upon a small washed filter, ignited separately, weighed, 
and added to the gain in weight of the crucible. From this 
was subtrad^ed the loss in weight of the precipitate upon 
fusion in a covered porcelain crucible. A descrip- 
tion of the dark room used for the experiments, and many 
other precautions and details, will be found in other 
papers {Proe. Amer, Acad,, xxviii., 24; xxxix., 74). The 
results are tabulated below. 

It remains only to bring together the results into one 
table. 

Final Averages, 
Oxygen = 16*000. 



I. 

II. 
III. 
IV. 

V. 



Average, rejeding I. above «■ 87*663 

The last average is probably most nearly corred. 

The analysis of strontic chloride has already been begun , 
and the prelimmary results indicate that the results given 
above are certainly not too high. For the present, then, 
the atomic weight of strontium may be taken as 87*66 if 
oxygen is 16*00, 87*44 if oxygen is 15*96, and 87*01 if 
oxygen is 15*88. 







Strontinm 






equala 


2Ag : SrBra 


First Series 


87*644 


ti II 


Second Series 


87*663 


ti It 


Third Series 


87-668 


2AgBr : SrBr^ 


First Series 


87*660 


II II 


Second Series 


87*659 


Total 


average • • . . 


• • «= 87*650 



NOTICES OF BOOKS. 



A Text-Book of the Science and Art 0/ Bread-Making, in- 
cluding the Chemistry and Analytical and Practical 
Testing of Wheat, Flour, and other Materials used in 
Baking. By William Jagg, F.I.C, F.C.S., Chemist 
to the National Association of Master Bakers and Con« 
fedlioners of Great Britain and Ireland ; Honorary Con- 
sultative Examiner in Bread-Making to the City and 
Guilds of London Institute for the Advancement of 
Technical Education ; Cantor Ledurer on ** Modem 
Developments of Bread-Making ** to the Society of Arts, 
London, &c. London : Simpkin, Marshall, Hamilton, 
Kent, and Co., Ltd. 1895. ^^^'i PP* ^4^* 
Thb baker holds a position essentially distindl from that, 
e.g., of the grocer, draper, &c. He does not merely boy 
in the wholesale market and sell by retail ; he obtains raw 
material and supplies it to his customers after it has 
undergone changes necessary to its general use as food. 
Hence he has not merely to make a judicious seledion of 
raw materials, but to carry oui the changes involved in 
the conversion of flour into bread. 

To effed these changes successfully and economically 
he must have acquaintances with certain principlea, 
mainly chemical, micro-biological, and physical. With- 
out such knowledge he may certainly, by rule-of-thumb, 
turn out good bread from January to December ; but he is 
at the mercy of accidents. An unusual sample of float 
or of yeast may any day show him to his cost that he is 
not master of the situation. 

The adulteration of flour is judiciously dealt with ; 
but we see here nothing to shake our belief that the 
intentional sophistication of flour and breads is less pre« 
valcnt than it was formerly. 



Aog. 9. 1895. f 



Chemical Notices from Foreign Sources. 



73 



The remarks on aluminous baking-powders (p. 489) 
convince us that, as long as our Courts tolerate quibbling 
in defence of frauds, Britain will not for some time witness 
the complete extirpation of sophistication. 

Perhaps the presence of the seeds of corn-cockle, 
darnel, ergot, &c., in flour, is more apt to occur than that 
of any adulterant purposely added. Due attention is here 
called to the examination of yeasts by microscopic and 
biological teste. 

The author shows that, contrary to what may be almost 
called a superstition, white bread is more nutritious than 
the so-called whole-meal breads. The reason of this is 
that bran contains no gluten. Whole-meal bread, fur- 
ther, by the irritating adion of the bran, accelerates 
the peristaltic movement of the bowel. Hence an excess 
of unutilised nitrogenous matter is found in the excreta 
of persons who have been fed on brown breads. The 
irritation of the bran may occasion unpleasant, and even 
dangerous, diarrhoea. 

Mr. Jago dwells, in a very instrutUve and convincing 
manner, on the sanitary defeats of urban bakeries, — on 
their underground situation, their defective ventilation, 
their frequent proximity to privies and other sources of 
nuisance. Nor does he forget to show the importance of 
kneading by machinery in place of hand-labour, which 
involves certain features most unappetising and possibly 
anti-sanitary. In the interest alike of the consumer and 
the working- baker, underground bakeries and hand-labour 
in kneading should be superseded. In these days of gas- 
engines, and of the eledric transmission of power, this 
can be done without burdening the masier-baker. 

Mr. Jago*s work is the more welcome because alien 
bukers succeed in finding a footing in this country — a (a€t 
unpleasant to all who believe in the good old principle 
■* Britain for the British," and especially to all who have 
had the opportunity of closely observing Continental 
nastiness as existing in most countries except Holland. 

We hope that the *' Text-book of the Science and Art 
of Bread-Making" will be widely circulated and care- 
fully studied." 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES 



NoTi.— All degrees of temperature are Ceotigrade unlets otherwise 
ezpretted. 

Coinptes Rmdus HAdomadaires des Seances^ de VAcademU 

des Sciences, Vol. cxxi.. No. 3, July 15, 1895. 
' Nominations.— As correspondent of the Sedion of 
Anatomy and Zoology, Sir William Flower was eleded, 
via Prof, van Beneden. Prof. Ramsay was eleded a 
correspondent for the Sedion of Chemistry, vice Dr. E. 
Fraokland. Singularly enough. Prof. Mendeleeff received 
only one vote. 

Deposit of Aluminium and Potassium Phosphate, 
and on the Genesis of these Minerals found in 
Algeria.— Ad. Carnot. — The deposit in question is found 
in the territory of Misserghin, near Tour Combes. It is 
found in a cavern of no considerable extent. It contains : 
Phosphoric acid, 35'i7 ; alumina. i8*i8; potassa, 5-80; 
ammonia, 0*48; lime, 0*31; silica, 11*60; water, with a 
Utile organic matter, volatile at loo', 13*40; do. ioo~ 
i8o*, 10*55; do. at redness, 4*35*; magnesia, fluorine, 
chlorine, sulphuric acid, traces; total, 9984. AH the 
fads observed may be explained by the in&ltrations of 
water. 

Ab8orption-8pe(5\rum of Liquefied Air. — Professors 
Liveing and Dewar.— (See p. 65 ). 

K€i\on of the Inra-rcd Rays upon Silver Sulphide. 
— lU. RigoUot.-*-ThiB paper will he inserted in full. 



Detection and the Presence of Laccase io Plants 
— G. Bertrand. — The author has discovered laccase in 
beetroot, carrots, and turnips, in the tubers of dahlia aodT 
potatoes, in asparagus, in lucerne, trefoil, rye-grass, in 
plums, pears, quinces, and chestnuts, and in the flower of 
the gardenia. 

Essence of Linalde.— Ph. Barbier and L. Bouveault. 
— : The essence in question contains diatomic and 
tetratomic terpenes, methylheptenone, licareol, licarhodol, 
and sesquiterpene. 



MISCELLANEOUS. 



Distindion between Coniin and Nicotin,— G. Heut 
(Archiv, der Pharmacie), — These substances behave dif- 
ferently with phenolph^halein. If we add to nicotin, 
dissolved in dilute alcohol of 0*95 to 0*96 sp. gr., a drop 
of a saturated solution of phenoiphihalein, the liquid is 
not coloured red, as it is at once m case of coniin. 

The German Association of Naturalists and 
Physicians.— We learn that the 67th Congress of this 
Association will be held at Liibeck from September i6th 
to 23rd. Scientific and medical men of all nations are 
invited, but the proceedings will be conduded exclusively 
in the German language. The subjeds treated of are 
resolved into two main groups, that of the natural sciences 
and that of medicine. The former resolves itself into 
three subordinate groups. The firftt of these includes 
the sedions for mathematics, astronomy, physic?, che- 
mistry, agricultural chemistry, agricultural experiments, 
and the lore of instruments. The second comprises the 
sedions for mineralogy, botany, zoology, anthropology, 
and geography. In the third group are the sedions for 
instrudion in mathematics and natural science. A great 
advantage of the German Association is that it is not 
encumbered with a sedion for political economy, a subjed 
for which there is ample ftcope elsewhere. 

Australasian Association for the Advancement of 
Science. — The Seventh Session of the above Association 
will be held in Sydney, from the 3rd to the zoth January, 
1897, under the Presidency of A. Liversidee, M.A., 
F.R.S., Professor of Chemistry, University of Sydney. 
The Presidents and Secretaries of the Sedions are as 
follows : — 

Astronomyt Mathematics ^ and Physics. — R. L. J. EUery, 
C.M.G., F.R.S.. Government Astronomer, Vid., Presi« 
dent; R. Threlfall, M.A., Professor of Physics, and 
J. Arthur Pollock, B.Sc, Demonstrator in Physics, Syd- 
ney University, Secretaries. 

CA«w«/ry.— T. C. Cloud, A.R.S.M., F.C.S., Manager 
Wallaroo Copper Works, South Australia, President; 
W. M. Hamlet, F.C.S., F.I.C., Government Analyst, 
N.S.W., Secretary. 

Geology and Mineralogy* — Captain F. W. Hutton, MA., 
F.R.S., F.G.S., Diredor of Canterbury Museum, and 
Ledurer in Geology, Christ Church, New Zealand, Pre- 
sident; T. W. £. David, B.A., F.G.S., Professor of 
Geology and Physical Geography, Sydney Univeisity, 
and £. F. Pittman, A.R.S.M., F.G.S., L.S., Government 
Geologist, N.S.W., and Ledurer in Mining, Sydney Uni- 
versity, Secretaries. 

Biology,— T, J. Parker, B.Sc, F.R.S., Professor of 
Biology, Otago University, Dunedin, New Zealand, Pre- 
sident ; W. A. Haswell, M.A., D.Sc, F.L.S., Professor 
of Biology, Sydney University, and J. H. Maiden, F.C.S., 
F.L.S., Curator, Technological Museum, Sydney, and 
Superintendent of Technical Education, N.S.W., Secre- 
taries. 

Geography. — H. S. W. Crummer, Secretary of the 
Royal Geographical Society of Australasia (N.S.W. 
Branch), Secretary. 



74 



Australasian Association /or the Advancement of Science. {^^Ani%%^y^ 



Ethnology and Anthropology.^ A, W. Howitt, F.G.S., 
Secretary for Mines, VIA., President ; John Fraser, B.A., 
LL.D., Sydney, Secretary. 

Economic Scienct and Agriculture, — R. M. Johnston, 
F.L.S., Government Statistician, Tasmania, President ; 
Walter Scott, M.A., Professor of Greek, Sydney Univer- 
sity, and F. B. Guthrie, F.C.S., Consulting Chemist to 
the Department of Agriculture, N.S.W., Secretaries. 

Enginetring and Architecture. — H. C. Stanley, M.I.C.E., 
Chief Engineer, Southern and Western Railway L'nes, 
Queensland, President ; J. W. Grimshaw, M. Inst. C.E., 
M.I. Mech. £., &c., Supervising Engineer, Harbours and 
Rivers Department, N.S.W., Secretary. 

Sanitary Science and Hygiene. — Hon. Allan Campbell, 
M.L.C., L.R.C.O., South Australia, President ; J. Ash- 
burton Thompson, M.D., Chief Medical Inspe^or, Board 
of Health, N.S.W., Secretary. 

Mental Science and Education, — John Shirley, B.Sc, 
Distrid Inspedor of Schools, Brisbane, Queensland, Pre- 
sident; Francis Anderson, M.A., Professor of Logic and 
Mental Philosophy, Sydney University, Secretary. 

Communications and Papers for the Meeting, or 
inquiries, may be addressed to the Permanent Hon. 
Secretary, The Chemical Laboratory, The University, 
Sydney, N.S.W. 

SOUTH WEST LONDON POLYTECHNIC, 

MAURESA ROAD, CHELSEA. S.W. 

The Governors are desirous of appointing a 
CHEMICAL DEMONSTRATOR to the above Institution. 
Salaiy /too per annum. The Demonstrator will be required to lee- 
ture to Junior ClaMea and help in the laboratory, under the super- 
vision of the Head Master. Knowledf^e of Applied Chemistry is 
desirable. AppUcationi, with three testimonials, must be received 
by Anguat a2. 

An ASSISTANT for the CHEMIOAL LABORATORY will also 
be appointed. Salary 25/- per week. Applications to be received by 
Aufust 20. 

Applications should be endorsed " Chemical Department." 

H. B. HARPER, Aaing Secretary. 

JufASON COLLEGE BIRMINGHAM. 

FACULTIES OP ARTS AND SCIENCE. 
8E88I 0N 189 5-96. 

THE SESSION WILL COMMENCE ON TUESDAY, 
OCTOBER I. 

Complete Courses of Instrudtion are provided for the various Ex- 
aminauons in Arts and Science and the Preliminary Scientific (M.S.) 
Examination of the Universit^f of London; for Students of Civil, 
Mechanical, or Ele^rical Engineering ; and for those who desire to 
obtain an acquaintance with some branch of applied science. 
Students may, however, attend any class or combination of classes. 

There is also a Faculty of Medicine. A Syllabus containing full 
particulars is publishtd by Messrs. Cornish^ New Street, Birmingham. 
Price 6d. ; by post yd, 

A SYLLABUS of the Faculties ol Arts and Science, containing 
full information as to the various leAure and laboratory courses, 
lecture days and hours, fees, entrance and other scboUrships, prizes, 
&c., is published by Messrs. Cornish, New Street, Birmingham. 
Price 6d.; by post 8d. 

Further information may be obtained on application. 

R. S. HEATH, Principal. 

GEO. H. MORLBY, Secretary and Registrar. 



OLD PLATINUM 

In ANY FORM PURCHASBD FOR CASH. 

Highest prices allowed by 

ROBERT PRINGLE & CO., Gold and Silver 

Refiners, &c., 40 and 42, Clerkenwell Rd., E.C. 

^ ^^ Send for Price List. 

,Mm^ Photogrsphic Residues reduced and purchased. 

ilicates of Soda and Potash in the state ol 

Soluble Glass, or in CONCENTRATED SOLUTION of first 
analitv. suited for the Manuiadture of Soap ana other purpoBes« 
5SSpHedoX«? terms by WILLIAM GOSSAGE AND SONS, 
Umitrd, Soap Works, Widnes, Lancashire. 

London Agents, COSTB and Co 19 ■nd ". Water Lane, Tower 
Strett, B.C., who bold stock ready for delivery. 




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CatMiCALNnrt,! 
Aug. 16, 1895* I 



Fuming Sulphuric Acid. 



75 



THE CHEMICAL NEWS. 



Vol. LXXIL, No. 1864. 



MOTB ON THB 

HBXYLENB, dtHu. and HBXYL-HYDRIDE, CiaH^, 
DERIVED FROM MANNITE BY REDUCTION 
WITH HYDRIODIC ACID.* 
^ By j. ALFRED WANKLYN. 

To- DAT it pQbltthed, in the Philosophical Ma^aMim, by 
Cooper aod myself ao ioTettigation of American petro- 
leom parallel with our inTetti^atioo of RuMian kerosene. 
The hydrocarbona exiating in American petroleum are 
aaembcr a of the marth-gaa family, at was shown by the 
dettifiil researches of Cahonrs and Pelonze, dating back 
to the years t86a and 1863. 

We now show that these marsh gases rise by incre- 
neots of 7. and not 14 as has hitherto been maintained. 
Oar investigation is at present confined to the more vola- 
tile part of the American oil, and we exhibit seven con- 
•ecative terms. 

Having in our hands the corresponding terms of the 
Rasstaa and American series, we are in a position to make 
a comparison of the physical charaders of the two sett 
of Isqnids. 

One of the most obvious fads brought oat by this com- 
ttarisoo ist that the Russian hydrocarbon is always a little 
bMvier than the American with the same carbon* 
ooadeosatkm. The increment of density is about 0*025 

lo o*<^s* 

More than thir^ years ago, when I was working with 
Erlenmeyer, it fell to my lot to investigate the two hydro- 
carbona, h«cylene and hexyl.hydride derived from man- 
Bite. Our account of these substances is published In the 
yommtil of ikt Chemical Sociiiy for the year 2863, in our 
ooojotnt paper entitled *' On the Hexyl Group." 

Ii happens that by accident (although the sp. gr. of 
bexylene waa determined with great care, in a thoroughly 
aatisladofy manner) it was never published. I now place 
it on record. ^ ^ . 

The spedmen of hexylene was prepared in the labora- 
tory of the University of Edinburgh, by decomposing the 
iodide of hexyl (from mannite) by alcoholic solution of 
potash. The purity of the hexylene was shown by very 
satisfadory combustions of the substance ; and here the 
remark nuy be made that good combustions afford deci- 
sive evidence of purity in a case of this kind, where no 
qoestioo of the presence of neighbouring homologues can 
arise. 

Two determinations of sp. gr. at 4*8'' C. and 45*5'' C. 
were made thus :— 

Sp. gr. at 4-8*» « 0*6972 
ft 455^ - 0-6604. 
water at a* C. being taken as unity, and the expansion of 
the glass being idlowed for. 

The sp. gr. of hexyl-hydride is given in our paper pub- 
Kabed in 1863, as 0*6645 at 16*5'' C. 

In the year 1864 I prepared the substance agam, and 
Bade another determination of the sp. gr^ at o^ C, and 
Soood It to be 0*6759 ; and, taking into account the cir- 
comstance that the temperature is lower than that in the 
former experiment, it is corroborative of the former. 

By a simple calculation we are able to compare the 
p. gr. of hexylene at o* with that of hexyl-hydride at the 



matt temperatoie :— 

Sow gr. of hexylene, daHn. at o* . . 

\, of hexyl-hydride, CuHmi •« ©• 



Difference 



—0*7017 
-0*6759 

—0*0258 



* !• ikisfvir lbs itomicwtight of cartoon is wtittea Si 0. 



It would thus appear that—whether the hydrocarbons 
are extraded by fradional distillation from a complex 
mixture of homologues, such as petroleum, or whether 
they are obtained by such a process as redudion of poly- 
atomic alcohols with hvdnodic acid--the relation be- 
tween the sp. gr. of CnHfi and the sp. gr. of CnHn-h, it 
the I 



Aegost X, 1895. 



CONCERNING FUMING SULPHURIC ACID. 
By R. W. HILL. 

The so-called Nordhausen or fuming sulphuric acid, 
HaSa07, is a compound of a molecule of ordinary sul- 
phuric acid, HaS04, with a molecule of sulphuric anhy- 
dride or sulphur trioxide, 80^. By heating the faming 
acid, the molecule of SO3 It readily driven off. 

Nearly everv text-book on chemistrv informs the student 
that this acid is still manufadured in Nordhausen, ia 
Saxony, Germany. As a matter of fad, it was never 
manufadured in the said town, but in Qoslar, a couple of 
miles from Nordhausen. At the present time, however, 
this acid is not manufadured at all either in or near that 
place ; but this particular chemical branch is, pradically 
speaking, monopolised by the large chemical ooncera of 
Johann D. Starck und S5hne, near Prac, Bohemia. They 
produce it in the old-fashioned manner by distilling green 
vitriol or ferrous sulphate,— 

Fea(S04)s - FeaOj +3SO3. 
The anhydride thus aiven off is absorbed by rain-water 
or sulphoriG add, 66^ Beaum^, thus producing laming 
acid. 

About twenty-five vears ago Professor CI. Winkler, of 
Freiberg, suggested toe use of platinised asbestos as a 
*' catalytic" substance for the union of pvrite— or brim- 
stone—kiln gas, SOa (sulphur dioxide), with the oxygen of 
air. The most favourable proportions are 29*6 vol. 
SOa +70*4 vol. atmospheric air (containing 14*8 vol. oxy- 
gen) ; but for pradical purposes it is advisable to employ 
a dry gaseous mixture of 25 per cent SOa+75 per cent 
air ; the dry anhydride does not attack cast* or tinned- 
iron. In some works in Russia and Germany this process 
is adually carried out on a commercial scale, with some 
modifications and improvements in the old idea. 

In Kalk, near Cologne, Germany, Wolter*s process is 
used, by distilling bydric sodic sulphate, — 

aNaHS04- NaaS04-|-SOs-|-HaO. 
The sulphate of soda is then treated with salphnric add, 
in order to get again bydric sulphate,-^ 

NaaS04+HaS04-aNaHS04. 

About five years ago a German chemist produced th^ 
fuming add from the ordinary sulphuric acid by meana 
of an eledric current. Carbon plates, about ith inch 
apart, were immersed into sulphuric monohydrate, and an 
eledric current passed through the fluid. The water of 
the acid is decomposed into hydrogen and oxygen, and 
the SOj is absorbed by the eledrolyte, this forming fuming 
sulphuric acid, S05-hHaS04— HaSaO;. As soon as a 
layer of sulphur is observed on the eledrodes, the current 
is reversed. As far as the writer knows, this eledrical 
process has never been tried on a commercial scale. 

Maocheiter, Angott j, tSss* 



German Ataociation. — Dr. H. KrCiss will read a 
paper on a ** New Procedure in Quantitative Spedral 
Analysis ** at the forthcoming Con^ss of the German 
Association of Naturalists and Physidans. At the same 
Congress Prof. W. Ostwald will read a paper 00 the 
** Vanquishing ol Scientific Materialism*'; and Prof. 
Svante Arrhenius will explain the fludnationa of climate 
in Geologic Epochs by aunnltaneout modifications in the 
proportions of Carbonic Add in the Air. — CA#mltfr 



76 



Gold and Silver in Copper and in Copper Matte. 



I CnBIIIC4L NlWt, 
I Aug. I6, 1895. 



GOLD AND SILVER IN COPPER AND IN 

COPPER MATTE. 

By ERNBST A. SMITH, Auoc. R.S.M., F.C.S. 

In averyinteresting paper* **0n a Uniform Method of Assay 
of Copper and of Copper Materials for Gold and for Silver,** 
by Dr. Albert R. Ledoux, of New York City, the author 
referred to the discrepancies which often occur in the re- 
sults obtained by different assayers working on the same 
sample, and suggested that some uniform method for 
assaying these materials should be arrived at, somewhat 
similar to the movement initiated by Prof. J. W. Langley, 
of Pittsburg, in 1888, which resulted in the general adop- 
tion of standard methods in the determination of carbon 
and other important elements in iron and steel. He pro- 
posed that a number of samples of gold- and silver- 
bearing copper material should be distributed to as many 
assayers as were willing to take part in the movement. 
In response to Dr. Ledoux*s paper, a large number of 
establishments and assayers expressed their willingness 
to co-operate in the plan he proposed. The necessary 
•amples were prepared by Dr. Ledoux, and distributed to 
the various parties co operating. The results obtained 
have been received recently and tabulated, in a paper pre- 
sented at the Florida meeting of the American Institute 
of Mining Engineers, and should be of interest to all 
those who have to assay similar materials in England. 
In discussing the various methods of assay in his paper, 
Dr. Ledoux draws attention to the fad that there is a 
divergence in the methods usually employed in the East 
and West for the assay of these copper materials. He 
points out that some of the Eastern public assayers use 
the ** wet ** method, which consists in tieating one assay- 
ton (about 30 grms. or 500 grains) of the sample of 
copper borings or matte in a (No. 5) beaker with a mix- 
ture of xoo c.c. water and 50 c.c. nitric acid of sp. gr. 1*42. 
When the violent adion has ceased, 50 cc. more of nitric 
acid is added, and the solution heated until everything 
soluble is dissolved. It is then boiled until the free nitric 
acid is expelled ; then diluted with 400 c.c. water and 5 
cc. sulpbttric acid, and xo c.c. of a concentrated solution 
of acetate or nitrate of lead added. The precipitate of 
lead sulphate is allowed to settle, filtered, and washed, 
and the filter and its contents are partially dried, then 
wrapped in thin lead-foil, and transferred to a scorifier. 
Cupellation is conduced in the usual manner. 

This method is intended for the determination of gold, 
but enough silver may be present to allow the bead to 
be parted. 

For silver the usual method in the East is to dissolve 
the sample in dilute nitric acid, as described above, and, 
before adding the lead salt, enough chloride of sodium is 
added to precipitate all the silver. The rest of the pro- 
cess is conduaed as for gold. 

In the West, the ** all-fire *' method of assay is em- 
ployed almost exclusively. 

At one works, ten portions'of the samples, each of one- 
tenth assay-ton (about 2| grms. or 50 grains), are scorified 
with 50 grms. of test-lead and a cover of i grm. of borax. 
The lead buttons obtained are cupelled separately, but 
the ten beads of precious metals obtained are weighed 
together. The cupels are then ground up and fused in 
five lots, of two cupels to each lot, with— 

Litharge • 90 grms. 

Boron glass • • • . 50 „ 

Soda carbonate • • 50 „ 

Argol 3 „ 

The silver obtained, after cupellation of the resulting 
lead buttons, is added to that from the first assay. All the 
beads are then parted for gold. 

Dr. Ledoux remarks that each of these methods in the 

* Read before the Bridgeport Meeting of the Amertcto lostUute 
of Minios Engineeni O^ber, 1894. 



hands of assayers skilled in its application will produce 
fairly uniform results, yet any assayer running the two 
methods side by side will get divergent figures for gold. 
It is stated that the results obtained by this method are 
usually higher than those obtained by the *' wet ** method. 
For mattes the same method is employed, but sometimes 
a second scorification is necessary, which is usually per- 
formed in a 2i-in. scorifier, with the addition of lead to 
make up the total to 35 grms. 

The necessary samples distributed to the various 
assayers were prepared in the following manner : — 

Copper MatU,—A carload of matte was put through a 
Blake crusher, then automatically sub-divided into tenths 
by a** Taylor and Brunton'* sampler, and one tenth 
passed through Cornish rolls, and then through a 12 mesh 
screen. This was again sub divided by an automatic 
sampler into tenths, and a final tenth, representing i per 
cent of the original lot, was finished by hand sampling on 
an iron floor until 100 lbs. remained. This was pulverised 
to pass a 40-me8h screen, and then thoroughly mixed and 
divided, in the presence of an assistant, for distribution 
to all tliose co-operating. 

Copptr Borings, — These were taken from a lot of 
anodes, the dip samples from several batches having been 
united, re-melted, and cast into a plate, which was proved 
by assay to be of uniform quality in its different parts. 
Borings from this plate were intimately mixed and divided 
in the presence of an assistant. 

The samples were stated to have approximately the fol- 
lowing compositions :^ j 



Copper , 
Gold . 
Silver < 



Copper •• 
Gold •• 
Silver • • 



Copper Matte, 

50 to 60 per cent. 

• • 2 to 3 ozs. per ton. 
.. xoo to 150 „ I, 

Coppir Borings. 

• • o'ao to 0*50 oss. per ton. 

• • 140 to 180 y, „ 



The detailed methods employed in each case are given 
in the paper presented to the Institute at the Florida 
meeting, and are substantiallv the same as those 
described. The restilts returned by the various assayers 
are as follows : — 



Returns for Sample of Copper Matte. 

Silver. 
O28. per ton< 



Gold. 
On, per too. 



Coppxa. 
Percent 



Com- EleAro- 



Com- 

Direa bined wet Diredt bined depod- Cyanide Iodide 
Bcorifica- andtcori- tcori- wetsnd tion method, method, 
tion. ficatkm. ficatioD. icori- method. 
ficatioD. 

I. i27'oo 130*68 2*22 2*310 55*o8 54*8o 55*00 

«• 135*38 127*60 2'35 2240 55*17 53*70 

3. 129*99 125-20 2*33 1*850 54*96 5272 

4. 131*89 129*72 2*41 2*260 55*04 50*55 

5. 128*95 12303 209 2*325 54*50 54*37 

6. 127*60 125*31 2*22 2*215 54'86 50*75 

7. 12875 12806 2*27 2*240 54*6o 

8. 122*88 128*27 228 2-260 55*o8 

9. 131*22 125*95 2*29 2*050 
10. 126*80 128*70 226 2' 160 
XX. 127*44 2*36 2*270 

12. 127*02 2*27 

13. X2870 2*33 
X4. 130*42 

Means 128*86 127*25 2*28 2*198 54*91 52'8x -55*00 

One " crucible " assay gave :— 

X 23^60 b^ES. of silver per ton. 



2*26 



geld 



C«RMICAt.NBWt,l 

Attf. |6, 1895. / 

Ooe combined *' wet and crucible ** assay gave :~ 

126*20 0Z8. of silver per too. 
a-og „ gold „ 

Ritumsfor SampU of Copper Borings* 



Purification of Glucinum Salts. 



77 





Silver. 


Gold. 


C0PP£B. 




On. per ton. 


Ozs. per ton. 


Per cent. 




' 


Combined 


Combined Eleftro- 




Dirta 


wet and 


Oirea 


wet and deposition Cyanide 




tconfica* 


•corific«- 


tcori- 


scorifica- 


method, method. 




tiOD. 


tion. 


ficatioo 


tion. 




I. 


159-33 


155-34 


0*30 


0*29 


97*45 9798 


3. 


15968 


160*78 


0*32 


0*24 


9704 


3. 


16435 


156-31 


0-35 


0*22 


98*19 


4- 


15912 


148*50 


040 


0*205 


98*46 


5- 


14740 


157*30 


0*35 


0*21 


9750 


6. 


«5575 


156*92 


0-35 


028 


97*37 


7- 


16405 


157-04 


0*30 


0-24 




8. 


154*40 


153*65 


0-40 


0-317 




9- 


15690 


161*40 


0*37 


0*30 




la 


160*63 


156 10 




0*25 




II. 




156*97 




0*22 




12. 




15967 




0*22 




»3. 




156*72 




0*501 




»4. 




159-27 




0*40 




15. 




14878 




0*26 




16. 




15900 




0*28 





Meani 158* 16 156*49 0*35 0*277 97*66 97*98 

One combined ** wet and crucible " assay gave : — 
i6i'35 ozs. of silver per too. 
0*42 ,• gold „ 
Prom the above tables the differences between the 
highest and lowest results returned are as follows :~ 

For Copper MatU, 

DIreA Combined wet and 

•corificatioD. acorification. 

Sihrer, oss. per ton 12*50 7*65 

Gold „ „ o*32o«6-4dwts. 0-475-9*5 dwts. 

For Copper Borings, 
Silver, ozs. per ton 16*95 12*90 

Gold „ „ 0*100 » 2*0 dwts. 0'296>a5 92 dwts. 

As Dr. C. B. Dudley remarks (in a paper read before 
the Chemical Sedlon of the Engineers* Society of Western 
Pennsylvania, 1892) :— ** There are four main causes of 
error to which may be attributed the discrepancies in 
analysis between the results of different workers :— 

1. The sample may not be uniform in composition, 
although supposed to be so. 

2. The degree of purity of the chemical reagents 
always varies. 

3. There is a ^ personal error " in manipulation, and 
there are various causes which prevent any particular 
method from being carried out in the usual way. 

4. The results given by each method may be regularly 
hi^er or lower than the truth.** 

The first cause of error is one which frequently occurs 
in commercial samples, and would lead to the suggestion 
that more uniform methods of sampling be adopted for 
the various materials under treatment, although in the 
copper materials under discussion the discrepancies are 
probably doe in a very minor degree to errors of sampling, 
and much more probably due in most cases to careless 
work and the use of inaccurate methods of analysis and 
assays. For assays in which assay lead is employed it 
is a matter of importance to take into account the amount 
of silver present, and to test every fresh sample of lead 
received for silver, as test-lead supplied as being •• free 
from silver ** can never be relied upon. Gold is invariably 
Trreseot (see esperimcnts by Richard Smith, Phil, Afag., 
Feb., 1854) in lead, but generally in such minute quant*. 



ties that it may be disregarded. The question of the 
silver in the lead used for the assay is often disregarded 
by assayers— a fad which may account for some of the 
discrepancies in the quantity of silver present in the 
copper materials operated upon. 

Other, and perhaps more important sources of error, are 
the temperature at which the cupellations are conduced 
and the subsequent treatment of the buttons in the 
** parting ** operation. Many assayers treat the buttons 
in one acid only in the *' parting*' process, and in some 
cases do not hesitate to use strong acid instead of dilute. 
The discrepancies may also be due to the want of a suf- 
ficiently accurate balance, a piece of chemical apparatus 
which is not always kept in the most perfed condition at 
metallurgical works. The errors likely to occur from this 
source cannot be too strongly impressed, when we bear 
in mind the comparatively small quantity of material 
operated upon, and the large increase in the error when 
the results are calculated to represent a ton of material. 

Mr. J. W. Westmoreland, an assayer with considerable 
experience in the assa^ of copper materials, in referring 
to the assay of gold m bar copper {youm, Soe. Chem, 
Ind.t Feb. 27, 1886), remarks that ** the general tendency 
is for the gold produce to be low, sometimes to a serious 
degree. ... I believe this is due to some extent to 
the insufficient weight of material operated upon.*' In 
using } oz. (240 grams) of copper chips for assay an error 
of o*oot grain in the weight of the gold would amount to 
3 dwts. of gold per ton (of 2240 lbs.) of copper. In the 
case of I oz. (480 grains) of copper chips, 0*001 grain 
would represent 14 dwts. per ton, but by careful weighing 
this could be reduced one-half, or to 18 grains per ton. 
He also remarks that ** one assayer made his gold assay 
on 100 grains of copper chips. In this case o'ooz grain 
in the weight of the gold, representing 6*5 dwts. per ton ; 
and it must be remembered that the value of this gold- 
varies from 2/- to 3/6 per dwt. ; hence the necessity for 
careful and accurate work.*' 

The results colle6ed by Dr. Ledoox are extremely 
interesting, and should be of value to all those engaged 
in assaying copper materials for silver and for gold. 
Royal School of Mioet, Loodoo. 



NOTE ON THE PURIFICATION OF GLUCINUM 

SALTS.* 

By BDWARD HART, 

Twenty years a|o I found glucinum in a clay brought to 
Dr. Drown*s private laboratory, in Philaidelphia, for 
analysis. The experience gained then in making the 
separation from alumina showed clearly that none of the 
methods then known gave a satisfadory separation. In 
dissolving the carbonate we found that alumina also 
dissolves, and that in treating the oxides with solution of 
ammonium chloride, alumina as well as glucina dissolves. 

In beginning the purification of glucina from beryl, 
which I have undertaken for a more careful study of the 
me^l and its alloys, I determined, if possible, to prepare 
it in some other way than by the use of the time- 
honoured ammonium carbonate method, which, besides 
giving a material of doubtful purity, is expensive and 
tedious. Such a method has been found based on the 
properties of the mixed sulphates from beryl, and which 
seems not to have been used for this purpose. Perhaps 
it will be best to describe the method now used in full, 
without describing the failures through which the work 
passed. 

The powdered beryl is first fused with mixed car- 
bonates, and then ground and washed with water. The 
powdered mass is then mixed with sulphuric acid and 

* Head at the Bostoo lleciiof of the Amcricaa Chsmkal Souct)r, 
U'.ccmbcriS. it<)%. 



78 



Fluorescent Spectrum of Argon described by Berthelot. 



I Cnbmical !!■»•, 
i Attf. l6, 1895. 



evaporated to make the silica insoluble. The sulphate 
solution obtained from this material is evaporated and 
treated with an excess of potassium sulphate. Alum 
crystallises oat, and is purified by re-crystallisation. The 
motber-li<}uor contains the glucinum along with the iron 
and alkaline sulphates. Potassium chlorate is added in 
excess, and the solution heated to peroxidise the iron. 
Sodium carbonate solution is now added, little by little, 
the solution being boiled after each addition until a fil- 
tered sample shows no yellow colour. The whole solution 
is then filtered, and the glucinum which will be contained 
in the filtrate is precipitated by further addition of sodium 
carbonate. 

The method, of course, depends upon the fad that it 
is impossible to throw down the glucinum until the greater 
part of the acid has been saturated, the glucinum remain- 
mg in solution as basic sulphate. Iron and aluminum, on 
the contrary, are easily separated. Some care is needed 
in order to get rid of the last trace of iron, which 
persistently remains in solution until the point at which 
the precipitation of glucinum begins is almost reached. 

A sample prepared in this way was perfedlly soluble in 
hydrochloric acid, gave no rea6ion for iron with potassium 
ferrocyanide, was completely soluble in an excess of am- 
monium carbonate and caustic potash. The ammonium 
carbonate solution gave no precipitate on the addition of 
ammonium oxalate. The method is exceedingly simple, 
convenient, and cheap, and leaves nothing to be desired. 
'^ Journal of thi American Chemical Society t xvii., 604. 



ON THS 

FLUORESCENT SPECTRUM OF ARGON 
. DESCRIBED BY PROFESSOR BERTHELOT. 

Berthelot has submitted a specimen of argon sent him 
by Professor Ramsay to the adion of the efiluve. In the 
speftrum of the fluorescent light Berthelot was able to 
distinguish four lines, the wave-lengths of which, as 
measured with a speAroscope of low dispersive power, 
were as follows :— 

579 millionths •• •• •• m.m. 

547 » — 

438 — 

436 ft — 

The limit of error was given as 3 to 5 of the last 
figures. 

The line 579 made the impression of a double line, as 
also 547. Besides there were also bands in the green and 
the violet, and especially in the red and the orange, the 
feeble illumination of which did not admit of a determina- 
tion of the wave>length. 

Berthelot ascribes the observed lines to argon, and 
thinks that he can recognise the following lines indicated 
by Crookes ; the degree of brightness of which is shown 
by the number in a bracket, where (10) expresses the 
greatest brightness. 

574*06 (6) 

J555-70 (10) 

1549-65 (8) 

433*35 (9) 

430-05 (9) 

It is. In the first place, highly improbable that among 
the numerous bright lines of the argon speArum only 
these should be left under the aAlon of the effluve. Why, 
e,g.f did not the lines — 

603*8 (8) 

565« (9) 

561-0 (9) 

518-58 (to) 

make their appearance ? 



The interpretation of Berthelot's observations is prob- 
ably this : That he has observed the spectrum 0/ mercury , 
and probably traces of the nitrogen speAtnm, 

The brightest lines of the mercurial spedrum, according 
to Thal^n are^ 



57896 
576-81 
54606 
435-81 



(10) 
(10 
(10 
(lol 



and agree with Berthelot's value as closely as might 
be at all expe^ed. Thal^n's first two lines correspond to 
line 579, seen double by Berthelot. We should ascribe 
Berthelot's line 438 to mercury, and 436 to nitrogen, 
which has a bright band at 734*60. 

We have further satisfied ourselves, by our own ob- 
servations, that at high pressures a small addition of nitro- 
gen to argon suffices to suppress almost entirely the argon 
spedrum. 

The bands observed by Berthelot in the red, yellow, 
green, and violet have probably belonged to nitrogen. 

We have repeatedly prepared argon, and in some cases 
we have also obtained a mercuriferous gas which showed 
Thal^n's four above-mentioned lines in full lustre. The 
conditions under which the metallic mercury used in the 
apparatus is taken up by the gas we are not yet able to 
give, but acetylene seems here to play a part which in 
Berthelot's experiments may have been formed from the 



effluve 



[)anying ti 
,'-Liehig's 



Annalen, cclxxxvii., p. 230. 



QUANTITATIVE ANALYSIS OP GALENA. 
By P. JANNASCH and H. KAM MBRBR. 

One of the present writers has formerly proposed several 
methods for the analysis of galena. The precipitation of 
the alkaline (sodium) solution of the sulphide oxidised to 
sulphate by the dired addition of bromine, and also the 
precipitation by hydrogen peroxide of an ammoniacal so- 
lution in ammonium acetate, were recommended as 
especially simple ; and, finally, as the most expeditious, 
the decomposition of the mineral in a current of bromine* 
The precipitation of the lead in an alkaline solution 
(potassic) by means of bromine was subsequently also 
used bv L. Medicus, the halogen being applied in the 
form of vapour. 

07 to 075 grm. of finely pulverised galena is placed in 
a porcelain capsule and moistened with dilute nitric acid, 
allowed to stand in the cold for some minutes, treated 
there with 10 c.c. of concentrated nitric acid, heated on 
the water-bath, and suitably evaporated. Nitric acid and 
water are added afresh, along with 10^x5 drops of bro- 
mine, and heated, with frequent stirring, until all the sul- 
phur is completely oxidised to sulphuric acid. 

For the certain destrudion of any bromate formed as a 
subsidiary produd, we evaporate the saline mass three 
times with concentrated nitric acid until dry as dust. 
When this has been efieded, the dry residue is boiled for 
a short time in a covered capsule with 60 c.c. of water 
and 20 c.c. of concentrated hydrochloric acid, so as to 
dissolve all the lead sulphate. The residual gangue is 
filtered off (using a tall beaker), the filter and the tube of 
the funnel are well washed with boiling water, incinerated, 
and weighed. 

For precipitating the lead, the filtrate is heated to 
ebullition on a free flame until complete solution has 
been effeded, and the liquid is poured into a previously 
prepared miiture of 25 c.c. water, 50 c.c. hydrogen per- 
oxide, and 50 c.c. concentrated ammonia. The lead is 
thus precipitated as a fine yellowish red partially crystal- 
line deposit, the composition of which will be determined 
subsequently. The whole is allowed to stand covered 
for several hours, with occasional stirring, filtered, washed 



Quantitative Determination oj Hydrazin and its Salts. 



Chbhical N«Wf,f 
Ang. i6, 1895. I 

carefully with cold water, dried, and weighed in a platinum 
crucible as lead oxide. 

For the determination of the sulphuric acid, the filtrate 
from the lead precipitate is evaporated on the water-bath 
until the odour of ammonia has disappeared ; 5 c.c. of 
concentrated hydrochloric acid, and the same volume of 
alcohol are added, and the whole is gently heated for 
tome time in order to re-generate certain quantities of 
persulphuric acid and to destroy with certainty any hydro- 
gen p^oxide still present. The sulphuric acid is then 
precipitated with the calculated quantity of solution of 
barium chloride. If this precaution is omitted, the results 
are much too low, in consequence of the solubility of 
barium persulphate. 

Small impurities of a galena, consisting of copper, 
nickel, zinc, or arsenic, will be found in case of the hy- 
drogen peroxide method in the ammoniacal filtrate, and 
after the separation of the sulphuric acid maybe separately 
determined by barium chlonde.-- Berichte, 1895, ^o. 11, 
p. 1409. _ 

ON THE RECOGNITION OF BLOOD SPOTS 

IN JUDICIAL CASES. 

By FRIED. GANTTKR. 

The detedion and demonstration of traces of blood upon 
rusty iron is known to be hindered, and in many casea 
rendered impossible, by the circumstance that it is not 
pradicable to obtain crystals of baemine, or to tfft6t other 
readioni for the demonstration of blood from the sub- 
stance which has been rendered insoluble by the ferric 
oxide. As a rule, in such cases, the result of the inveiti- 
gation^specially if it has had to be undertaken after 
prolonged conta^ with the rusty iron — is to this effed, 
that it has not been possible to show the presence of 
blood with certainty ; but that this, in view of the great 
difficulty of recognising blood under such conditions, isffo 
proof of the total absence of blood upon the article in 
question. But very often it is not merely to show the 
pnsiHCt of blood, but quite as important to give a certain 
proof of its entire absena, i. e., to prove that the spots in 
question are certainly not due to blood. 

For the latter purpose the behaviour of the blood- 
substance with hydrogen peroxide is a good means. If a 
drop of the solution of hydrogen peroxide is brought in 
contad with the slightest trace of the substance of blood, 
there occurs immediately a distindly visible evolution of 
oxygen gas proceeding from the blood, and gradually in- 
creasing, so that the drop is very soon converted into a 
white frothy mass, which retains its froth-like charader 
for a long time. This readion is most distindly mani- 
fested as follows : — 

Upon a port-objed — which for the sake of greater 
distindness we lay upon black paper — we place a drop of 
the solution of the blood substance, or, if such a solution 
cannot be obtained, as in case of spots on rusty iron, a 
small portion of the scrapings of the rust, which is 
covered with a drop of a very weak alkaline water, and 
allowed to stand for some minutes to soften the blood 
substance. We then add a drop of solution of hydrogen 
peroxide, when, if the smallest trace of blood substance 
is present, relatively large gas-bubbles are evolved ; in 
case of sanguiferous rust, we see that the development of 
gas does not proceed uniformly from all parts of the rust, 
but merely from certain points, i. e., from such only to 
which particles of blood adhere. The gas-bubbles, after 
some time, coalesce to a tender froth, which on the black 
paper appears snow-white, and which remains for some 
hours without melting away. It is a charaderistic feature 
that this froth contrads from the margin of the drop to- 
wards the middle, so that the sharply limited white foam 
appears surrounded by a ring of clear liquid, 

To mistake the phenomenon for ordinary air-vesicles is 
scarcely possible. Certainly, on moistening the rust with 



?9_ 

the feebly alkaline water, single air-babbles often appeart 
but they soon disappear if touched with a slender glass 
rod before the hydrogen peroxide is added. 

If the readion does not appear it is certain evidence 
that the rust-spots contain no blood. Inversely, how* 
ever, the appearance of the readion is no positive evidence 
of the presence of blood, since the animal fluids, #. g,, 
pus, behave with hydrogen peroxide in the same manner 
as blood. 

The readion may also be usefully applied for the closer 
examination of the crystals of hsemioe, if, as it some- 
times happens, we are in doubt whether the crjrstals 
obtained are really those of hsemine. If we treat the 
microscopic preparation containing the crystals in the 
manner described above, there occurs at once a strong 
development of gas, whilst no change occurs if the crys* 
tals are other than those of haemine. 

The readion is also suitable for a convenient prelimi- 
nary examination of spots supposed to be blood. The 
age of the spots upon rusty iron does not seem to have 
any marked influence on the distindness of the readion ; 
at least spots six months old showed the readion as 
sharply as those freshly obtSilntd.^ZeU fur Anal, Chim.t 
vol. xxxiv., p. 159. 



QUANTITATIVE DETERMINATION OF 

HYDRAZIN IN ITS SALTS. 

By JULIUS PBTERSOff. 

For this purpose Peterson utilises its well-known reduc- 
tive adion with Fehling's solution or with potassium 
permanganate. 

Curtius {yourn Prnkt, Chimii, N. S., xxxviii.« p. 4x8) 
recommends boiling the hydrochlorate with hydrochloric 
solutions of platinum chloride, and colleding the nitrogen 
evolved. The process takes place according to the 
equation — 

NaH4,2HCl + aPtCl4 = Ni+6Ha + aPtCls» 

The author's experiments show that the proportion of 
nitrogen obtained is too high by about x per cftnt. 

The volumetric method depends on the use of iodine, 
and is founded on the following readion :— 

5NaH4HaO -J- 4I - 4(NaH4,HI) + sHjO + N,. 
It is applicable only for the hydrate, and is therefore of no 
universal importance. 

Peterson's attempts to determine hydraxin with 
boiling Fehling's solution show that the proceas takes 
place according to the equation— 

N2H4 -I- O2 = 2HaO + N2. 

The author was not able to obtain constant resnlts by 
titration ; but a perfedly accurate determination of hy- 
drazin can be efteded by colleding and measuring the 
nitrogen liberated. 

Peterson proceeds in the same manner as Stracbe in 
his determinations of the carbonyl-number. 

The determination is effeded as follows :— 

In a small flask, holding about 25 c.c, and capable of 
being closed with a caoutchouc stopper having two per- 
forations, there is introduced a quantity of Fehling's 
solution, excessive in proportion to the substance to be 
used, and previously diluted with water to about 60 cc, 
and heated to boiling. The stopper of the flask contains, 
in one of its perforations, a small glass tube, introduced 
from below, containing the weighed substance, and a 
small glass rod introduced from above. In the other 
perforation is a gas-delivery tube, through which the air 
is first expelled by wgtery vapour. When this has been 
effeded, a measuring tube (hlled with water previously 
boiled out) is placed over the gas-delivery tube, the lamp 
beneath the flask is withdrawn for a moment, and the 
little tube containing the substance is thrown into the 



8o 



Chemistry of the Cyanide Process. 



I Chbmical M|W8, 
I Aug. i6t i&gs. 



liqaid by pushing in the glass rod. After a brief ebullition 
all the nitrogen is driven over, and can be measured in 
the usual manner. The tube used for introducing the 
substance contains about ^ c.c. As it cannot be entirely 
filled, a corredion of about iV c*c* i^ made in the volume 
of the nitrogen, 

Hydrasin may also be determined by titration with 
potassium permanganate in a hot solution. 

The titrations must be tSe&td at 60^ to 70*^, and the 
solution roust contain from 6 to 12 per cent sulphuric 
acid. We titrate in the ordinary manner. The titration 
is completed when, on further addition of the solution of 
permanganate, the liquid becomes more and more deeply 
coloured, when we titrate back with oxalic acid. 

The oxidation, according to the author's experiments, 
takes place according to the equation — 
X7(NaH4,HaS04) + 13O « 

-i3HaO + 7(NH4)aS04 + loNa + ioHaS04. 
The accuracy of the equation is proved by the consump 
tion of the permanganate, the determination of the 
ammonia formed, as well as by measuring the nitrogen 
liberated,— Z#i7. Anorg. ChimU, vol. v., p. x. 



ACTION OP THB INFRARED RAYS UPON 

SILVER SULPHIDE. 

By H. RIQOLLOT. 

It is known that silver sulphide, sensitive both to lumi- 
Dous and obscure radiations, may be employed as an 
eledro-cheroical adinometer. I have studied the adion 
of the infra-red rays upon this compound, and have 
examined if the sensitiveness of silver sulphide to radia- 
tions is a thermo-eleAric aAion or depends on some other 
cause. 

Two plates of silver sulphide, immersed in a dilute 
saline solution, formed an eledro-chemical aAinometer. 
The sulphuretted plates were prepared by eleArolysing a 
solution of sodium sulphide by a feeble current for two 
minutes. They were about 2 m.m. in width by 40 m.m. 
in length ; they were paraffined on the sides facing each 
other, one only being exposed to the radiations studied. 
The a^nometer, conneAed either to a Thomson gal- 
vanometer of the resistance of 25,000 ohms, or to a 
Lippmann eledrometer, was successively exposed to the 
various radiations of a prismatic spedlrum of the length 
of 55 m.m. from the rays D to G. 

Under these conditions the sensitiveness of silver sul- 
phide for the infra-red radiations is recognised to a great 
distance from the last visible radiations. The galvano- 
meter still gives indications for the wave-length fi 1*32, 
and we find in the solar spedra the two minima at /i 0*96 
and /A z*i6, and the chief maximum fi 1*04 as signalised 
by Langley. The eledromotive force developed by the 
most adive part of the infra- red spedrum, the slit having 
only the width of 1*4 m.m., is of 3 to 4 thousandths volt. 
In the visible spedrum the sensitiveness decreases very 
rapidly from the ray A to the ray F, becoming then neg- 
ligible. The illuminated plate is always negative with 
reference to the other, whatever may be the solution 
employed. 

In another series of experiments, in order to compare 
the thermo-eledric eflfeds with the luminous effeds, there 
were employed plates of a greater breadth, about 6 m.m. ; 
each of the two plates plunged into one branch of a 
U-tube of glass, containing a veiy dilute solution of silver 
nitrate or of sodium chloride. One of the limbs of the 
tube was surrounded with a glass jacket, and by filling 
the annular space with hot water we could establish be- 
tween the two limbs of the U-tube a difference of tem- 
perature, ascertained by means of thermometers immersed 
in each limb. On the other hand, in the tube itself, the 
plate intended to be heated might be illuminated by a 
Bengel burner, the luminous intensity of which corre- I 



sponds to that of a Carcel lamp, placed at the distance 
of 0*20 metre. The li{p;ht fell upon the plate only for a 
very short time, the efifed produced being instantaneous. 
The eledromotive forces developed, whether by the 
difference of temperature or by light, were recorded at 
above. 

It was observed that the light instantly produced a 
negative eledromotive force of about x^Vb ^^^U and that, 
on heating, it was necessary to establish between the two 
plates a difference of temperature of 6^ to 7% to develope 
the same eledromotive force, negative in silver nitrate, 
positive in sodium chloride. 

On taking as liquids dilute solutions of NaBr, Nal, 
KBr, KI, K2SO4, MgS04, AgS04, CaH^AgOa. it was 
found that the illuminated plate is always nep;ative with 
relation to the other, whilst the heated plate is negative 
only in solutions of salts of silver, and positive in solu* 
tions of the other salts tried. 

The two series of experiments are certainly not iden- 
tical, but I believe that they have a sufficiency of points 
in common, so that there being the difference of tem- 
perature necessary to develope an eledromotive force 
of o'oo2 volt, it would be difficult to admit that the adion 
of the infra-red rays it merely thermic— Bk/Z. d4 la Soc 
Chim. 



REPORT OF EXPERIMENTS ON THB 

CHEMISTRY OF THE CYANIDE PROCESS, 

AND NOTES ON ITS WORKING. 

New Procbss for Dbtbrmimino Cyanides. 

Solubility of Gold in Double Cyanidbs and in 

Hydrochloric Acid. 

Phbnolphthalein as an Indicator in Titrating 

Potassium Cyanidb.* 

By O. A. QOYDER, F.C.S., 

Analyst aod Assayer to the South Anitralian School of llioet 

and Industries. 

When at the Government cyanide works at Mount 
Torrens in April last I noticed that the process in general 
use for determining the amount of ** available " or simple 
cyanide of potassium, namely, titration of a known 
volume of solution by means of a standard solution of 
nitrate of silver, with the addition of a little potassium 
iodide to give a sharper end reaAion, although it gave 
accurate results with ordinary solutions of potassium 
cyanide, in the presence of double cyanide salts the end 
readion was ill-defined, and after making numerous ex- 
periments it appeared that in titrating the sump solutions, 
which contain much of their cyanogen as the double 
cyanide of zinc and potassium, the end readion was not 
only ill-defined, but that the quantity of nitrate of silver 
required to produce a permanent turbidity increased with 
the dilution, with the temperature, and also with the 
amount of simple cyanide added to a greater extent than 
was calculated. Thus a sump solution, which titrated 
cold indicated 0*015 per cent of simple cyanide of potas- 
sium, after heating quickly on a water-bath indicated 0*07 
per cent, or nearly five times as much. If, however, the 
heating and titration are done slowly much of the cyano- 
gen is decomposed and lower figures obtained. A cold 
sump solution, to which nitrate of silver has been added 
to permanent turbidity on shaking, always clears on being 
heated. A i per cent solution of crystallised double 
cyanide of sine and potassium on titration as above ap* 
peared to contain one-thirtieth of its total cyanogen as 
simple cyanide of potassium ; on diluting to sixteen times 
the bulk it indicated one-third of the total as simple 
cyanide, and by further diluting to two hundred and fifty 
times the bulk the whole of the cyanogen appeared by 
titration to be simple cyanide. 



• From ihe Sixth Annual Report of the Council. AachUde 1693. 



CBBMICAI.N«Wt,l 



Chemistry of the Cyanide Process. 



8i 



As regards the indcfioiieoets of the reaAion, a sample 
of sump solution was divided iDto three equal portions. 
To No. a an eqaal volume and to No. 3 two volumes of 
distilled water were added, and these were given to an 
expert, well acquainted with the process, but not knowing 
how the solutions were made up, to test. He reported 
that No. I contained 0*04 per cent, No. 2 0*05 per cent, 
and No. 3 0*04 per cent of simple cyanide. It is evident 
that if No. I contained 0*04. No. a could only have con- 
Uined half, and No. 3 one-third of that amount if the 
process were reliable. 

Again, a sample of sump solution, which by the above 
test contained o'oa per cent of simple cyanide, was 
strengthened up by pure cyanide of potassium, so that it 
was calculated to contain 0*09 per cent, but it now ap- 
peared to contain 0*15 per cent, so that at least 0*06 per 
cent of double cyanide was returned as simple cyanide. 
There may, however, be cases in which the addition of 
cyanide of potassium to sump liquors would not have this 
efled. Thus, supposing the solution to contain the double 
cyanide of iron and potassium, the addition of the proper 
amount of cyanide of potassium to this would produce 
lerrocyanide of potassium, KaPeCy^+aKCy»K4PeCy6, 
and on titration the cyanide of potassium would be found 
to have disappeared. In aAual work, therefore, the re- 
sults obtained by this method are only comparative, and 
it would indicate to some extent where a large excess of 
cranide was used in lixiviation. If the solutions were 
alkaline the indications would again be interfered with, 
at will be shown b^ what follows. 

I therefore modified the above process by adding a 
decided excess of caustic soda to the sump solutions be- 
lore testing. If a precipitate is produced it is better to 
add, say, 10 c.c. of 5 per cent caustic soda to ao c.c. of 
sump solution, shake, pass through a dry filter, and take 
15 c.c. of the filtrate for titration. When this solution 
is titrated with nitrate of silver after the addition of a 
little potassium iodide the end readion is exceedingly 
sharp ; a decided excess of caustic alkali does not inter- 
fere, and the precipitate is not dissolved by heating. This 
method, however, not only indicates the simple alkaline 
cyanide present, but also the cyanogen present in the 
original solntioo as sine-potassium cyanide. This pro- 
ccsa was used by roe at Mount Torrens last April in 
watching the progress of lixiviation, and its indications 
gave much more exad information as to the progress than 
could be obtained by the ordinary process. According to 
an extrad from the youmal Chemical Industry^ Nov., 
1894 ("The Cyanide Process"), W. R. Fcldtmann 
{Bmgintit and Minitig yourtial, Iviii., 1894, 318—319) ^*s 
experimented with this process, and states :—** Addition 
of alkali to working solutions which have become some- 
what weak in alkali biiogs up the strength by regenerating, 
i./.,decomoosiog the zinc cyanide, ... so that, as 
a matter of fad, when the solutions are pretty strongly 
alkaline they contain no zinc as cyanide, but only as hy- 
drate dissolved in alkali (zincate of potash, &c.).*' 

But I believe that caustic alkali is never added in large 
excess 10 the lixiviating solutions, and when added in 
small qtuntities the double decomposition would not be 
complete, and its amount could only be calculated by ap- 
plying the laws of chemical mass a6ion after finding the 
relative ptoportion of the double cyanide of zinc and 
potassium to caustic alkali, and the velocity of combina- 
tion of the resulting salts. As in pradice this problem is 
complicated by the pretence of the double salts and 
caustic potash as well as other salts, its solution is prob- 
ably impossible. It may, however, be taken for granted 
that when caustic alkali is added to a solution of double 

Sanide of potassium and zinc in molecular proportions 
D resulting soluUon will after a little time contain 
zincate of potash, cyanide of potassium, and the double 
salt. 

Having recently found that hydrocyanic acid does not 
dccoloarise phenolphthalein, and that cyanide of notas- 
ftiuro is alkaline to that indicator, while the doable , 



cyanides are neutral, I have endeavoured to bate 00 theia 
readions a new process for finding the amount of aimple 
cyanide of potassium present in sump liquors, &c. In the 
presence of caustic alkali or alkaline carbonates this pro- 
cess could not be applied ; bicarbonates do not inteifere 
if the titration is made in a stoppered bottle with the 
necessary precautions. The titration is made by measur- 
ing 100 c.c. of sump solution, or solution after pasting 
through the tailings, into a stoppered bottle, adding i c.c. 
of one-twentieth per cent phenolphthalein and running in 
decinormal hydrochloric acid till the pink colour is 
destroyed ; i c.c. of the acid«o-oo65 per cent of cyanide 
of potassium present. By this readion I have found that at 
a rule the sump solutions do not contain more than 0*0004 
to 0*003 per cent of simple cyanide of potassium as a 
maximum amount, and that from this amount any caustic 
alkali or alkaline carbonate present must be deduded, so 
that it would appear that the solutions after passing the 
zinc boxes contain pradically no simple cyanide of potas- 
sium, but that it is all converted into double salts. The 
following analysis of sump liquor from Mount Torrent 
confirms this opinion :— 

Analysis of Sump Liquor from Mount Tomnt afiir 
Passing Zinc Box$s, 

Analysis. 

Psrccat. 

Copper 0*0030 Ferrocyanide of 

Zinc 0*0178 potassium •• 0*0400 

Iron •• •• •• 0*0001 Copper-potassium 

Calcium .. •• 0*0145 cyanide •• •• 0*0073 

Magnesium . .. 0*0043 Zinc • potassium 

Potassium •• •• 00609 cyanide •• •• 0*0676 

Sodium 0*0645 *Calcium carbonate 0*0363 

Chlorine .. .. 0*0875 'Magnesium carb. 0*0147 

Cyanogen •• .. 0*0477 *Potassiumcarb... 0*0035 

Sulphuric acid Potassium tul- 

radicle •• .. 0*0401 phate . •• •• 0*0431 

Carbonic acid Sodium sulphate • 0*0341 

radicle •• •• 0*0333 Sodium chloride • 0*1442 



Assumed composltioa of salts 
insoiotloD. 

Ptfosnt. 



Total.. 



0*3796 



Total.. 



0*3796 



* The carbooatei woald b« in the solntioo as WcarbooatM, bat art 
here fivrn at timple carbooatea to laciHtatt conparisoo. 

In addition to the above, the solution also contained 
traces of cobalt, mercury, silver, and gold. The flour 
mercury retained in the tailings from the battery is dis- 
solved by the cyanide ; some of it is again precipitated in 
the t.iilings by any soluble sulphide present in the solu- 
tion, and the bulk of the remainder is precipitated in the 
zinc boxes. The quantity of mercury in the gold slimes 
from the zinc boxes is sometimes large in amount, and 
makes the fumes rising from them during ignition 
decidedly poisonous. 

When discussing with Mr. L. W. Orayson, the manager 
of the Government plant at Mount Torrens, the altera- 
tions necessary to the old plant, I suggested that the 
3-in. pipes leading from the lx>ttom of the lixiviation vats, 
which are 8 ft. in diameter, should be reduced to l-in., and 
that syphon bottles should be attached to the lower ends of 
these pipes by indiarubber tubing, the neck of the bottles 
being also furnished with indiarubber tubes, which could be 
direded into the openings of main lines of pipes leading 
respedively into the waste water tanks, the weak solution, 
and strong solution zinc boxes. These suggestions were 
carried out by Mr. Grayson, and it was found on testing 
them, that these small pipes, as soon as the solutions 
started running from the vats, became filled, and exerted 
a sudion equal to between 4 ft. and 5 ft. of water^their 
vertical height — and thus hastened the rate of lixiviation, 
or permitted of tailings with a larger proportion of slimes 
being treated than would have been possible had the 3-in. 
pipes been retained, as the solutions could not be run 
through the tailings at such a rate as to fill 3-in. pipes. 



82 



New Bacterial PigmttU. 



f Chbmical Nbwi, 
I Auff. i6, 1895. 



and unless fall ihey could not produce any sudion. The 
progress of lixiviation can be readily judged by the 
appearance of the solution passing through the syphon 
l)ottle8, and the rate of flow adjusted by taps at the lower 
end of the pipes near the bottles. With tailings of 
moderate fineness these taps are only one-third to one- 
half open to produce the requisite rate of flow. 

The method of conducing the lixiviation suggested by 
me as suitable for the Mount Torrens plant was as fol- 
lows : — During the filling of a vat the tap of the draw-off 
pipe was left open, and the syphon bottle removed, so that 
as much water as possible was drained off from the 
tailings. Each truck-load was levelled down with a rake 
until the vat was nearly full ; the top was then levelled as 
accurately as possible, and strong solution of about 0'2 
per cent cyanide of potassium to the amount of about 
one*third the weight of the ore was run in at the top. 
This solution, if the vat had been well and evenly filled 
with tailings, sank slowly and almost without a bubble, 
driving the interstitial air before it, and out by the draw- 
off tap at the bottom, whence it escaped with considerable 
force, and displacing the residual water which, after a 
time, escapes by the draw-off pipe in general quite clear 
and colourless. As soon as the air has all escaped and 
the water flows in a steady stream, the syphon bottle is 
attached and the stream direded to the waste water 
tank. After a further interval, the liquid in the bottle 
begins to assume a yellowish tint, wh^n the stream is 
direded into the small zinc boxes, and the rate of flow 
reduced, so that the strong solution displaced by the ad- 
dition of an equal bulk of weak or sump solution at the 
top, would flow through in the time found by experience 
to afford the best payable extradion. When the last of 
the weak solution has sunk to the level of the top of the 
tailings, w^sh water is added to displace it, and the rate 
of flow may be now increased to save time. When the 
solution in the syphon bottles has again become nearly 
colourless, the lixiviation process is finished. The im- 
portance of having the draw-off pipe at the lowest point 
of the vat, and having the bottom of the vat sloping to- 
wards it from all directions, may be noted here. In such 
a case the water and different solutions have scarcely any 
tendency to mix, and the line between them is sharp, and 
therefore the bulk of the residual water first coming out 
can be run away without danger of loss of gold, instead 
of being mixed with the cyanide solution, diluting it, and 
increasing its bulk. At the end, too, the last of the weak 
solution IS displaced with much less admixture of water, 
and as the bulk of solutions in stock is always kept about 
the same, the care exercised in properly coostruding the 
vats is more than repaid by a saving of gold and of 
cyanide. 

(To be continaed.) 



A NEW BACTERIAL PIGMENT. 
By ALBERT THORPE. 

As the chemistry of the baderial pigments is a subjed 
which has been veiy little investigated, the present note 
may be of interest. 

I have isolated the brown pigment from infusions of 
maize undergoing putrefadlion by means of the Bacterium 
brunntum. This pigment is soluble in alcohol, and is pre- 
cipitated from an alcoholic solution by the addition of 
water. The precipitate, after filtration, was re-dissolved 
in alcohol, and the solution evaporated to dryness at 40*^ 
C. The following figures were obtained on the analysis of 
this pigment :— 0-4764 grm. of substance gave i'358 grm. 
of COa and 0*232 grm. of HaO. 





Fouod. 


Calculated for Cj,H|«Oa 


Carbon • . 


•. 7774 


7769 


Hydrogen , 


5'62 


503 


Oxygen . . 


• . ^"^ 


17-28 



From the foregoing percentage composition* C18H14O3 
represents the formula of this brown pigment. 

The alcoholic solution of the pigment gave no 
charaderistic absorption-bands when examined by means 
of the spedroscope. 

This pigment is soluble in alcohol, ether, and chloro- 
form, insoluble in water and carbon disulphide, and acids 
appear to destroy it. 



NOTICES OF BOOKS. 



Life and Labour of the Peofle in London, Edited by 
Charles Booth. Vol. VI., Population Classified by 
Trades (continued). 8vo., pp. 383. London and New 
York : Macmillan and Co. 1895. 

This work contains much interesting matter, but also 
much that cannot come under our cognisance at aU. 

The total number of persons employed in the manufac- 
tures of surgical, *' philosophical " — we strongly objed to 
this term^and electrical instruments is 8258, more than 
half of whom are engaged in the produdion of eledrical 
appliances, and 2000 of whom nre under 25 years of age. 

As regards surgical instruments, we are not sorry to 
learn that the hospitals and the leading operators do not 
approve of importations from the Continent. Microscopes 
of German make are, on the contrary, highly appreciated. 
In this and the kindred trades a really good workman is 
at a premium. 

Concerning the manufadure of spedroscopes, chemical 
balances, and other requisites for the physical and chemical 
laboratory, we believe that an increasing proportion are 
of German make. The same fad must, beyond doubt, be 
admitted concerning glass and porcelain scientific appa- 
ratus. In the coloured glass manufadure we find it re- 
marked that an Italian or French working man might 
perhaps develope an artistic sense of his own, but this, 
apparently, an Englishman can rarely do. This is a faA 
gravely to be regretted. Concerning the poUery trade, 
we learn that ** betting, even more than drink, is now the 
ruling extravagance.*' 

The persons employed in the chemical arts amount to 
5836, a portion of whom are merely manufadurers of 
blacking, of matches, and of ** proprietary " medicines. 
The rank and file of the chemical workmen earn little 
more than 25s. per week. There is no complaint of un- 
healthiness, save in the white-lead works. Among the 
match-makers necrosis in the jaw is greatly decreasing. 
Still it is very desirable that the use of white phosphorus 
should cease entirely. Indeed the entire elimination of 
phosphorus in the match-trade, and that of white-lead in 
pigment-making, rank among the most important problems 
of chemical industry. 

Concerning soap, we think that Mr. G. H. Duckworth 
goes too far in asserting without qualification that ** the 
fats used are of the most disagreeable nature." What of 
the Russian and Australian tallows, the palm- and cocoa- 
nut oils ? The total of the persons employed in this 
business, and in bone-boiling, candle-making, &c., amoant 
to 2195, and their wages rarely exceed 30s. weekly. 

The unsavoury businesses of the tanner, fellmongcr, 
currier, furrier, &c., employ 15,739 persons. The men 
employed are accused— we fear truthfully— of a tendency 
to drink to excess. The employment, especially of those 
who prepare furs for the hatters, is unhealthy, and no type 
of respirator hitherto devised has been found suitable. 

As for the textile trades we are, of course, most con- 
cerned with the dyeing and cleaning departments. 
Dyeing on the large scale, as applied to new goods, can 
scarcely be said to exist in London, though the garment 
dyer, once numerous, is gradually diminishing. Leaving 
out of the question provincial competition, the London 
garment dyer is now poached upon by the monopolist 






Manufacture of Aluminium Sulphate. 



83 



draper and by the jobbing tailor. Tbe nomber of persons 
employed in the trade is now given as 1946. Concerning 
health there is little room for complaint. Indeed, in the 
manoiaaoring distrids of Yorkshire and Lancashire, it is 
a common saying that a dead dyer is as great a rarity as 
a dead donkey. Tbe chief peril to the dyer and cleaner 
aprioga from the ignition or explosion of the vapoor of 
**bcnsoline spirit." Two injarions substances encoon- 
tered in the waterproofing business are sulphur chloride 
and carbon disulphide. Hitherto no method of obviating 
Iheir hurtful effeas, or of superseding them by means of 
any harmless substance, has been elaborated. 

The general impression produced by a perusal of this 
work is far from pleasing. We see a number of trades 
declining, and in many others the average remuneration 
obtained by the workers is not sufficient Tor the demands 
ol a healthy life. 

ThiMamttfactnu of Aluminium Sulphate (Die Pabrikation 

von Schwefelsaurer Thonerde). By Dr. Konrad W. 

B. JuaiscH. Docent at the Royal Technical High 

School, of Berlin. Berlin : Fischer & Heilmann. 
Wb have here a useful monograph of aluminium sul- 
phate, or, as it is sometimes called, ** concentrated alum.*' 
The author describes the raw materials, their sources, the 
process of manufadure, tbe properties and applications of 
the finished produd, and the statistics of the trade. 

Analyses are given of native sulphates from various 
paru of the world, the best being apparently that from 
Adelaide. The alum-shales and native alum-earths are 
corredly pronounced of little value for the manufadure 
ia qoMUon. 

The number of patents for the produdion of aluminium 
talphate is truly appalling. But it is evident that the 
early attempts to use clays and felspar for the manufac- 
Ittte either of alum or of aluminium sulphate are being 
more and more restrided, since bauxite — a far preferable 
material— is now obtainable in increasing quantities. 
Cryolite (6NaF,AlaF6) is indeed an excellent material ; 
but the only locality where it is obtained in quantity 
and in full purity is Arsak, in the south of Greenland. 
A sample from Miask was found not free from ferric 
oside. Ccyolite is at present used only at the Oeresund 
works, near Copenhagen, and at the Natrona works near 
Pitubvrg, in Pennsylvania. 

Egliaton clay is mentioned as a raw material, but its 
composition is not stated. The produd contains 0*15 to 
o*ao per cent Fe, and is consequently unfit for the uses of 
the paper-maker and tbe tissue-printer. We fear that 
•ome confusion in terminology has crept in, since we have 
beard the name Eglinton clay used as a synonym for 
gibbsite. 

Bauxite is described as the leading material for the 
prodndion of sulphate of alumina. The best quality is 
that from the neighbourhood of Belfast, as used by 
P. Spence and Snence Brothers of Manchester, and 
latsed by the Irish Hill Mining Co. The best quality, the 
ao-called ** Gertrude-bauxite,** contains only 0*53 per cent 
of FeaOs, whilst many French sorts contain upwards of 
20 per cent of this ver^ troublesome impurity. 

lo working up bauxites the process generally followed 
ia that of LechateHer, which consists essentially in igni- 
tion with toda, lixiviation with water, filtration, and pre- 
cipitation with carbonic acid, which of course throws 
down aluminium hvdroaide ; filtration and re-solution in 
sulphuric acid, which 00 cooling yields the commercial 
** cake-alum.** For the details we must refer to the work 
of Dr. JuriKh. The outlook of the manufadure is very 
fairly summed up in the words that the present task of 
the cake-alum maker is to produce regularly and certainly 
an alnmininm sulphate as free at possible from iron, con- 
taining from 14 to X4.5 per cent AlgOj, containing neither 
free acid nor excess of alumina, and giving a clear solu. 
tioo in water. 

There is given an extended table showing the specific 



gravities and the percentage contents of solatioos of cake- 
alum from 1*005 'o I '341* 

The basic sulphate Ala(H0}a(S04)a is precipitated on 
dilution. 

The impurities most dreaded in commercial cake-alum 
are iron and free acid. Samples containing from 0*0(9 
to 0*01 per cent of iron are commonly said to be free from 
iron, though many dyers and tissue printers dread evea 
these traces. In the case especially of pink and rose 
shades, and hence prefer ordinary alum. Traces of iron, 
not exceeding 0*05 per cent can be determined colori- 
metrically. The free acid in cake-alum rarely exceeds 0*5 
per cent. It is allowed by the maker to remain, not on 
account of the difficulty of its removal, but to give the 
produd a better colour. In presence of free acid, 0*05 
per cent of ferric oxide does not occasion a yellowish 
colour. 

The uses of cake-alum are as a mordant — or material 
for mordants^n dyeing and tissue-printing, in paper- 
making, in the sixing process, and in tawing hides fin 
these applications the absence of iron is most essential), 
and as a purifier for sewage and waste waters containing 
organic pollution. For this last purpose the presence of 
ferric sulphate — as in Spence*s alumino-ferric cake — is 
not at all objedionable. We may remark that where 
hydrochloric acid is available, an aluminium hydro- 
chlorate, obtained either from hydrargyllite or from iron 
slags, is preferable to the sulphate for the treatment of 
sewage. 

Dr. Jurisch, by the publication of this work, has con- 
ferred a substantial benefit upon the producers and coo- 
sumers of cake-alum. 



Cap$ of Good Hopi, Dtparlminl of AgricuUun. Repori 
of thi Siuior Analyst on thi Analytical Laboratory for 
tk* Yiar 1894. Cape Town : W. A. Richards and 
Sons. 1895. 

Thb Analyst reports that the work of the Department 
has increased progressively from 47 In 1889 to 506 to 
1894. '^^^ xhxt^ Government Laboratories of Cape 
Town, that conneded with the Adulteration Ad, with 
the Department of Agriculture, and with the Geological 
and Irrigation Office, have been amalffamated. 

Tbe subsunces given in for analjrsu were very promis- 
cuous, samples of milk being the most nnmeroos. Of the 
ia4 samples 4a were found to be adulterated, and of tbe 
38 coffees 10 had been sophisticated. In case of milk, 
the fraud has consisted In skimming and in the addition 
of water. The milk of a cow, in an advanced stage of 
phthisis, showed: — Total solids, 9*39; milk fat, a*6o; 
solids not fat, 679; and water, 90*61. 

The adulteration of coflfoe was solely with chicoiy, 
which in one case— from Kimberley— reached the alarming 
proportion of 67 per cent 1 One sample of whiskv was 
totally faditious. The samples of pepper examined were 
all found to be genuine. 

Of gold-quarts 54 samples were examined, of fdiich 
25 showed not a trace of gold. Of the aamplea received 
from Mashona Land two contained i{ ounces per ton, 
and one as much as 6| ounces. 

Three samples of coal were found to be of fair qnalitv, 
and an anthracite from Xalanga, in Tembaland, is likely 
to prove of great value. 

The only sample of nitre sent in was one from Prieska, 
containing 98*9 per cent of potassium nitrate. 

A lode of sulphur in admixture with graphite may be 
valuable if the finder is not mistaken as regards its 
extent. 

The waters were not satisfadory. That from the 
Gamtoas River Bridge is more saline than the Indian 
Ocean. Out of 33 samples of water only 5 were fit for 
use, 7 doubtful, and the rest polluted and unfit for 
use. Out of 81 samples of well-water 71 were bad, io* 
eluding 39 from Cape Town aod its distrid* 



84 

The foils show generally a deficiency in phosphoric 
acid, and in many instances also in potash. 

A sample of peat-ash from Durban was found exceed- 
ingly poor. 

Two native barks contained respedively 25 and 26 per 
cent of tannin. If abundant they may be exported to 
advantage. 

Two samples of Cape tea have been examined. These 
were not ordinary teas grown in Africa, but were obtained 
from native shrubs. They contained no theine or any 
similar alkaloid. 

Vlnduitrii Chimique (Chemical Industry). By A. 
Haller, Diredor of the Chemical InKitute of the 
Faculty of Sciences of Nancy, Correspondent of the 
Academy of Sciences and the Academy of Medicine. 
Pp. 348. Paris , J. B. Bailli^re et Fils. 1895. 
This compaA work forms the first volume of a series 
entitled the " Encyclopaedia of Industrial Chemistry and 
Metallarsy." It treats more especially of higher instruc- 
tion in different countries ; of the produds of the heavy 
chemical industry, the works, and their recent improve- 
ments ; of chemical and pharmaceutical produds, espe- 
cially the produds little known or recently discovered ; 
artificial colouring matters ; essential oils, and raw mate- 
rials for perfumery. 

The first of these heads is of the deepest and roost 
general interest. It is admitted that the German che- 
mical manufaaurers are constantly growing at the expense 
of those of France and Britain. The causes of this su- 
periority are manifold ; but first and foremost stands the 
organisation of the German Universities, who are here 
aptly pronounced to be ** the makers of the national glory 
and prosperity.** There is no restraint, no subjedion to 
any narrow pre-arranged " syllabus." The professors 
enjoy that freedom of spirit which is moat favourable 
to high culture, and which is not met with in any 
other country. The interference of the public authorities 
in questions of the penonnel of a university is as restrided 
as possible. The universities, though dependent on the 
State and paid by it, enjoy an autonomy which enables 
them to choose their redors, their deans of faculty, and 
their professors, and present them to the Minister of 
Public Instrudion for formal nomination, and it is very 
-rare for the Government to interfere with the choice of 
the Senalus Academicus, 

To be called to the occupation of a chair it is not ne- 
cessary to produce numerous certificates, to undergo 
depressing competitions which throw no light on the 
originative power of the candidate. It is merely requi- 
site for him to have given proof of originality in research, 
and 10 have manifested himself a pioneer in Science. A 
Rector htagnificus — sl dignitary essentially equivalent 
to the Chancellor of an English University or to the 
Lord Redor in Scotland — has not to undergo, like the 
latter, eledion on the principles of political fadion, or to 
be seleded by a body consisting mainly of half-pay 
officers. A candidate for a professorship of experimental 
science has not to be ••heckled *' on points of theological 
controversy or to sign a confession of faith. The student 
has not to waste precious time and priceless brain-power 
in preparing for successive examinations, and the inventor 
has not to meet the interference of alien patentees who 
obtain patents without any intention of pradising them 
upon German soil. To meet with competition so 
arranged our industrialists, bound as they are by a vicious 
system, would have to be superhuman. 

It is interesting to find that the institutions of higher 
instrudion cost only sd. annually per head of the popula- 
tion. Are they not an incomparably better investment 
than the Board Schools of Britain ? 

Besides the twenty-two Universities of the German 
Empire, the Polytechnic Schools of Aix-la-Chapelle, 
Carlsruhe, Brunswick, Charlottenburg, Darmstadt, Dres- 
den, Hanover, Munich, Stuttgart, the Mining Schools of 



Chemical Notices from Foreign Sources. 



{ 



Chrhical News, 
Aug, 16, 1:^5. 



Berlin, Clausthal, and Freiberg, and the Agricultural 
Schools, are almost all well provided with laboratories 
where researches in pure chemistry are carried on along 
with studies in applied chemistry. And these institutions 
are confided to men of proved scientific authority, who 
make it their task not merely to initiate the young stu- 
dents in the pradice of chemistry, but to rouse in them 
the spirit of research and guide them into the track of 
discovery. 

By means of the influx of foreign students, German 
science and German ideas are diffused, and at the same 
time German merchandise and German produds. In the 
years 1891 and 1892 there were not fewer than 446 stu- 
dents of American nationality studying at German 
Universities ; and not fewer than 800 at the Polytechnics, 
the Mining and Agricultural Colleges of Germany. 
Shall we reconsider our ways, or shall we go on examining 
and being examined, until we arrive at a universal collapse 
such as our Chinese models and forerunners in examina- 
tionism have just reached ? 



CORRESPONDENCE. 



BORAX AND STANDARD ACID SOLUTIONS. 

To the Editor of the Chetmcal News. 
Sir, — If our method of standardising acid solutions by 
means of borax is not new, as Mr. Droop Richmond says 
in Chbmical News, vol. Ixxii., p. 5, we at least have 
discovered it independently, and have done something to 
make it better known. 

Our aim was not to show to what accuracy the method 
could be carried, but rather to point out that, without 
taking any special precautions, results of very fair accu- 
racy could be obtained. 

We do not consider it necessary to estimate the water 
of crystallisation if large clear crystals of borax are used, 
but as this may be open to question, we intend making 
further experiments to test this point. The results we 
obtained were certainly good enough for ordinary analyti- 
cal work. One of the results is evidently a little incor- 
red, but probably through no fault of the method em- 
ployed. We do not know why Mr. Richmond should have 
dragged carbon dioxide into the question. — We are, &c., 

E. P. PSRUAN. 

W. John. 

University College. Cardiff, 
Augott 6, 1895. 



CHEMICAL 



NOTICES FROM FOREIGN 
SOURCES. 



NoTi.— All degrees of temperature are Centigrade anlets otherwise 

expreMed. 

Zeitschrififur Analytische Chtmie. 
Vol. xxxiii., Part 6. 

(This part has appeared only after vol. xxxiv. has already 
commenced appearing). 

Wine Statistics of Germany. VII.— A continuation 
of a voluminous report interesting exclusively to the wine 
trade. 

Acid Potassium Tartrate aa a Fundamental Sab- 
stance for Volumetry.— A. Bomtrager.— The pure acid 
tartrate has come into use for standardising alkaline 8ola> 
tions, and is giving satisfadion. 

Experiments on the Speed of Filtration of various 
Solutions. —K. Leze.— From Comptts Rtndus^ CKi^^t p. 
X440. 



CaSMlCAL MBWf 1 1 



Chemical Notices from Foreign Sources. 



85 



On Pyrometry.— Various construaiont have been dis- 
Ctt«fled or proposed by Roberts- Austen (paper at Chicago 
loternatioDal Congress, 1883), C. Gabb \Stahl undEistn), 
Uehliog and Steim>art {Stahl und Bistu). 

A small Air Thermometer for Laboratories. — 
Lotbar Meyer (BwUhU^ xxvi., X047) proposes a modifica- 
tion, here figured, of Bottomley's thermometer (see Phil. 
Mag., z888). 

Volumeter for Determining the Volames of large 
Samples, especially Soils.^Tacke (Zeit AngiwandU 
CAnRM#}w— Readers are referred to the originals for details. 

New Form of Weighing Pipette.— H. Schweitzer.— 
From the youmal of iht Amtrican Chimical Sociity. 

Self-aaing Apparatus for Filtration and for 
Washing Precipitates with Cold or Hot Water.— 
P. N. Ratkow (Ch€mik$r ZW/im^).— This paper requires 
the two accompanying figures. 

A Minimum Qas Blast.— Hugo Schiff (Chtmikir 
Ziihmg), — ^Tbis paper also cannot be reproduced without 
the accompanying illustration. 

Protedive Capsules for Platinum Crucibles.— H. 
Petrzilka.~The author uses platinum capsules, gilt with- 
oQt, so as to withstand smoking flames, of such a shape 
and sise as to completely cover the bottom of the cru- 
cible as far as the flame extends. 

Determination of Carbon in Iron.— A conspedus 
of the most general methods for determining the carbon 
contained in iron, as proposed by A. Ledebur (Vert in Mur 
Bel/ord. di Oewirb Fleisses); Regnault, JQptner, and 
Gmelin (** Handbuch fiir Eisenhiitten Chemiker *') ; 
Samstrdm, UUgren and Elliott, McCreath, Ruriip 
ICkimiker Zeitung) ; Barba (Stahl und Bisin) ; Langley, 
Blair, Dudley, and Shimer (Zeii. Ang$wandU Chtmii^ 
Mining youmal); Lorenz (Zeit. AngewandU Chtmii); 
Woehler, Eggertx, Ukena {Stahl und Eisen). 

Melting and Boiling Points of the Phenols and 
their Beosoates. — ^A. B^hal and E. Choay.— From the 
Comptis Rindus, czviii., p. Z2xz. 

Determination of Nitrogen.— W. P. Keating Stock. 
— From the Analyst, xviii., 58. 

Determination of the Thioureas, and their Separa- 
tion from the Sulphocyanides. — H. Salkowski 
{Bsruhti).—lQ solutions of pure thioureas the total sul- 
phur is precipitated as silver sulphide by ammoniacal 
Mihrtt nitrate. It is filtered off", washed, and heated, first 
over the simple Bunsen flame, and then fused over the 
gas blast. All the silver sulphide is thus converted into 
sUTer, from the weight of which the quantity of thiourea 
is calcolated. a atoms of silver represent i mol. of 
thiourea. For separating thioureas from the sulpho- 
cjranides, the clear solution is mixed with an excess of 
ammoniacal solution of silver. A mixture of silver sul- 
phide and sulphocyanide is precipitated, though a part of 
the latter remains in solution. After some hours the 
conversion of the thioureas is completed, when the precipi- 
tate-is filtered and washed. The filtrate is acidified with 
aulphuric acid, and the precipitate of silver sulphocyanide 
is allowed to stand in darkness. The washed precipitate 
is digested in the cold with solution of potassium cyanide 
ontil all the silver sulphocyanide is dissolved. After 
dilution it is filtered, and the washed silver sulphide 
is weighed as silver in the manner mentioned above. The 
filtrate is acidulated with sulphuric acid and heated on 
the water-bath ontil all the hydrocyanic acid is expelled. 
If this is delayed, silver sulphocyanide remains in solu- 
tion. The silver sulphocyanide thus obtained, along with 
that which had been set aside in the dark, is filtered on a 
filler which has been dried at 203^ After filtering and 
drying at 105* the silver sulphocyanide is weighed. 

DeteAton of the Pat of the Ox in Lard.—W. F. 
Keating Stock.— From the Analyst, xix., a. 



Determination of Hubl's Iodine Number. » W* 
Fahrion {Chtmikcr Zeitung, xvii., p. xioo). — The author 
observes that methylic alcohol is preferable to ethylic 
alcohol for the preparation of Hi^brs iodine solution. The 
solution of sublimate-iodine in methylic alcohol certainly 
becomes weaker in time, but not to the same extent as 
the solution in ethylic alcohol. Fahrion shows also 
that along with the addition of iodine atoms to the double 
combinations of the non-saturated fatty acids there ensue 
other processes, so that in general the iodine number is 
found rather higher than would correspond to the proper* 
tion of non-saturated fatty acids in the oil. A high 
temperature and exposure to light increases the numl^r 
considerably. 

Determination of the Melting-point of Solids.— E. 
J. Bevan. — From the Analyst, xviii., p. 286. 

Determination of Fatty Matter in Milk.— The pro- 
cess of Leo Liebermann and S. Ssekely has been verified 
and recommended by Long (Pharm. Ziitung). 

Arrangemement for a Rapid Approximate Deter- 
mination of the Quantity and Purity of Carbonic 
Acid in Mineral Waters, ftc— Th. Kyll (Ziit. Angtw. 
Chemii), — Apparently a hollow corkscrew ending m a 
three-way cock. 

Chemistry of Vegetable Fibres.— C. F. Cross, E. J. 
Bevan, aod C. Beadle.— From the Chemical News, 
Ixviii., p. 227. 

Examination of the Ethereal Oils.— Schimmel and 
Co.— A very extensive paper, not suitable for abstraAion. 

Method for the Volumetric Determination of the 
Phosphoric Acid, Soluble in Water, contained in 
Superphosphates. — W. Kalman and K. Meissels. — 
Already inserted. 

Determination of Uric Acid, and of the so-called 
Xanthine-substances in Urine. — £. Salkowski (C#ii- 
tralblatt /. Mtd. Wissenschaft).^T\i\% paper will also be 
inserted in full. 

DeteAion of Glucose and other Csetohydrates in 
Urine.— K. Baisch (Ztit. Physiol. CA#iini/).— This paper 
will also be inserted in full. 

Examination of Blood-pigment as to its Absorbent 
Power for the Violet and Ulira-Violet Rays.— H. 
Grabe. — Already inserted. 

The Atomic Weight of Barium. — T. W. Kichards 
(Anur, Acad. Arts and Sciences), — Already inserted. 



MISCELLANEOUS. 

The Drug and Chemical Trades Exhibition.— We 
have the pleasure of announcing that, on the zoth, nth, 
X2th, and 13th of next month, there will be held in the 
Royal Agricultural Hall, N. (Islington), an Exhibition of 
the Drug, Chemical, and Allied Trades. The promoters, 
subscril^rs to the British and Colonial Druggist, hope 
to render this demonstration a periodically recurring dis- 
play, so that it may bring under the notice of the trades 
and of their customers all improvements, new produAs, 
and procedures which may present themselves. The 
promoters admit that former exhibitions in connexion 
with the drug and chemical trades have not proved suc- 
cessful. On the present occasion the management will 
not only be entiiely new, but a general attendance of the 
trade is praAically guaranteed, and most of the leading 
firms concerned have already promised their support to 
the undertaking, and intend to be represented. No de- 
partment of our national industry and commerce requires 
to be more energetically and prudently supported than 
that in question. We hope that enlightened self-interest, 
not less than patriotism, will combine to ensure the suc- 
cess of the present Bahibitloo. 



86 



Award of the Hodgkins Prize. 



{ Chemical Ntwt, 
( Aug. i6, 1895. 



Award of the Hodgkins Prize of xo,ooo Dollars 
to Lord Rayleigb and Professor Ramsay. — In 
March, 1893, >^ ^^^ announced by the Smithsonian Insti- 
tntion, in furtherance of the wishes of Mr. Thomas 
Hodgkins, who had presented a large donation to the 
Institution for the ** increase and diffusion of more exadl 
knowledge in regard to the nature and properties of 
atmospheric air, in connexion with the welfare of man," 
that a prize of zo,ooo dollars would be given for a treatise 
embodying some new and important discovery in regard 
to the nature and properties of atmospheric air. The 
competing treatises had to be sent in before the end of 
December, 1894. We have much pleasure in announcing 
that this prize has been awarded to Lord Rayleigh and 
Professor Ramsay for their treatise on the discovery of 
Argon. 

Clay Filters, and their Use in Chemical and 
Baderiological Laboratories.— W. Pukall {BerichU).-^ 
The author has produced filters which have not the soft 
sensitive surface of the Chamberland or the Berkefeld 
(Kieselguhr) filters, but have in a high degree the power 
of transmitting gases or liquids on the application of ex- 
haustion from below or pressure from above. The filters 
consist of a suitable composition of china clays of different 
beds (aluminium silicate with ouartz), which can be 
sharply burnt though remaining sufficiently porous. The 
construAion recommended by Pukall is figured in the 
original. 



HARRIS INSTITUTE, PRESTON. 

Wanted, an Assistant to the Professor of 
Chemistry. A praAicml knowledge required of General and 
Agricoltnral Chemietry, with some experience in Analytical work. 
Salary, £100 a year. Applications, stating qualifications, and accom- 
panied by copies of three Testimonials, to be forwarded before the 
jst of September, 2895, U>~- 

T. R. JOLLY, Secretary. 

SOUTH WEST LONDON POLYTECHNIC, 

MAURESA ROAD, CHBLSKA, S.W. 

The Governors are desirous of appointing a 
CHEMICAL DEMONSTRATOR to the above Institution. 
Salary £100 per annum. The Demonstrator will be required to lec- 
ture to Junior Classes and help in the laboratory, under the super- 
vision of the Head Master. Knowledge of Applied Chemistry is 
desirable. Applications, with three testimonials, must be received 
by August 22. 

An ASSISTANT for the CHEMICAL LABORATORY will also 
be appointed. Salary 23/* per week. Applications to be received by 
August 20. 

Applications should be endorsed ** Chemical Department." 

H. D. HARPER, AAing Secretar>'. 

J^ASON COLLEGE BIRMINGHAM. 

FACULTIES OP ARTS AND SCIENCE. 
8E88 iON 189 5-96. 

THE SESSION WILL COMMENCE ON TUESDAY. 
OCTOBER X. 

Complete Coorses of Instrudtion are provided for the various Ex- 
aminations in Arts and Science and the Preliminary Scientific (M.B.) 
Examination of the University of London: for Students of Civil, 
Mechanical, or Electrical Engineering ; and for those who desire to 
obtain an acquaintance with some branch of applied science. 
Students may, oowever, attend any class or combination of classes. 

There is also a Faculty of Medicine. A Syllabus containing full 
particulars is published by Messrs, Comish^New Street,Birmingham» 
Price 6d. ; ^ post yd. 

A SYLLABUS of the Faculties of Aru and Science, containing 
foil information as to the various le^ure and laboratory courses, 
le^nre days and hours, fees, entrance and other scholarships, prizes, 
ftc, is published by Messrs. Cornish, New Street, Birmingham. 
Price 6d.s by post 8d. 

Farther information may be obtained on application. 

R. S. HEATH, Principal. 

GEO. a. MORLBY, Secretary and Regiatntr. 



J. & A. CHURCHILL, 
PU BLISHER S. 

PRACTICAL CHEMISTRY AND 

QUALITATIVE ANALYSIS; Specially adapted for Colleges 
and Scheols. By FRANK CLOWES, D.Sc, Professor of Che- 
mistry in University College, Nottingham. Sixth Edition, with 
84 Engravings, Post 8vo, 85. 6d. 

ELEMENTARYQUALITATIVE ANA- 
LYSIS ; suitable for Organised Science Schools. By FRANK 
CLOWES, D.Sc.Lond., Professor of Chemistry in University 
College, Nottingham, and J. BERNARD COLEMAN, Senior 
Demonstrator,of Chemistry in University College, Nottingham. 
With Engravings. Post 8vo, ar. 6d, 

BY THE SAME AUTHORS. 

QUANTITATIVE ANALYSIS: specially 

adapted for Colleges and Schools. Third Edition, with 100 En- 
gravings, Post 8vo, gi. [jutt ready, 

VALENTIN'S QUALITATIVE ANA- 
LYSIS. Edited by Dr. W. R. HODGKINSON. F.R.S.E., Pro- 
fessor of Chemistry and Physics in the Royal MiliUry AcademT 
and Artillery College, Woolwich. Eighth Edition, Revised and 
Enlarged, 8r. 6d, 

BLOXAM'S CHEMISTRY, INOR- 

GANIC AND ORGANIC, with ExperimenU. Re-written and 
Revised bv JOHN MILLAR THOMSON, Professor of Chemia- 
try. King^i College, London, and ARTHUR G. BLOXAM, 
Head of the Chemistry Department, The Goldsmiths' Institute, 
New Cross, London. Eighth Edition, with 281 Engravings, 8vo, 
z8i. 6d. 

BLOXAM'S LABORATORY TEACH- 
ING; Or, Progressive Exercises in PraAical Chemistry. 
Edited by ARTHUR G. BLOXAM, Head of the Chemist^ 
Department. The Go.dsmiths* Institute, London. Sixth Editioa, 
Revised and much Enlarged, with 80 Woodcots, Crown 8to, 
6s. 6d, 

CHEMISTRY OF URINE; a Praaical 

Guide to the Analytical Examinations of Diabetic, Alburaiooua. 
and Gouty Urine. By ALFRED H. ALLEN, P.I.C., P.C.S. 
With Engravings, 8vo, ys. 6d. 

London : 
J. & A. CHURCHILL, 11, New Burlington Strebt. 



ACETONE — Angwcriog all reqairements. 

A.CIX) .A.OETIC— Pwreat and sweet. 

- BOIR A.CIO-Cryat. and powder. 

OIT3aiC— Cryst. made in earthenware. 

C3-.A.IjXjIO— From best Chinese galls, pure, 

S.A.XiIO YXilO-By Kolbe's process. 

T.A.I?r2fTIO-For Pharmacy and the Arts. 

LIQUID CHLORINE 

(Compressed in steel cylinders). 

FORMALIN (40^ CHaO)— Aniiscpiic and PretcrvaUve. 

POTASS. PBRMANGANATB— Cryst., large and small. 

SULPHOCYANIDE OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EM ETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THE ARTS. 



A. 



Wholesale Agents— 

& M. ZIMMERMANN, 

6 & 7, CROSS LANE LONDON, E.C. 



Albumens, PasteSi Gumsy Glues, Prepared 

f^ Hom.Piths. Vegetable Sisei, dc, ftc.— W. KOHQt Bwmb 



* ^ Horn-Piths. 
Street, LiverpoolJ 



ClIBlftCALNBWt,! 
Aug, 23, l8w- I 



Spectrum of Helium. 



87 



THE CHEMICAL NEWS. 



Vol. LXXIL, No. 1865. 



THE SPECTRUM OF HELIUM. 
By WILLIAM CROOKES, F.R.S. 

Ik the Cbbmical News for March 29th last (vol. lxxi.» p. 
I5i) I pablithed the resalts of measuremeots of the 
wave-lengtht of the more promiDent lines seen in the 
tpe^ftmm of the cm from cl^veite, now identified with 
helinm. The gaa nad been given to me by the discoverer, 
Profeator Ramsay ; and being from the first batch prepared, 
it contained other gases m impurities, such as nitrogen and 
mqueons vapour, both of which gave spcAra interfering 
with the purity of the true helium spedtrum. I have since, 
thanks to the lundness of Professors Ramsay and J. Norman 
Lockyer, had an opportunity of examining samples of 
helium from difFerent minerals and of considerable 
purity as far as known contamination is concerned. 
These samples of gas were sealed in tubes of various 
kinds and exhausted to the most luminous point for spec- 
trum observations. In most cases no internal eledrodes 
were used, but the rarefied gas was illuminated solely by 
induAion, metallic terminals being attached to the outside 
of the tube.* For photographic purposes, a quarts window 
was attached to the end of the tube, so that the spedrum 
of the gas could bo taken '* end on." 

My examinations have chiefly been made on five 
tamplea of gas. 

I. A sample from Professor Ramsay in March last. 
Prepared from Cldveite. 

a* A sample from Professor Ramsay in May last. Pre- 
pared from a specimen of Uraninite sent to him by 
Professor Hillebrand. Qas obtained by means of 
sulphuric acid ; purified by sparking. 

3. A sample from Professor Ramsay in June last. Pre- 

pared from BrogKcrite. 

4. A sample from Professor Lockyer in July last. Pre- 

pared by a process of fradional distillation from a 
sample of br6ggerite sent to him by Professor 
Brogger. 

5. A sample of gas from Professor Ramsay, '* Helium 

Purissimum." This was obtained from mixed 
sources, and had been purified to the highest 
possible point. 

lo the following table the first four samples of gas will 
be called:^!. "Cliveite, R."; a. "Uraninite, R."; 3. 
*• Br6ggerite, R."; and 4. ** Brdggerite, L.*' Only the 
strongest of the lines, and those about which I have no 
doobt, are given. The wave-lengths are on Rowland's 
•cale. 

The photographs were taken on plates bent to the 
proper corvattire for bringing the whole speftmm in 
sccorate focus at the same time. The spedruro given by 
m spark between an alloy of equal atoms of mercury, 
cadmium, ainc, and tin, was photographed at the same 
time on the plate, partially overlapping the helium 
■pedram ; suitable lines of these metals were used as 
standards. The measurements were taken by means 
of a special micrometer reading approximately to the 
i/ioo,oooth inch, and with accuracy to the i/io,oooth of 
an inch. The calculations were performed according to 
Sir George Stokes's formula, supplemented by an addt- 
tiooal formula kindly supplied by Sir George Stokes, 
giving a correAion to be applied to the approximate 



• JctmuUt^ths ItutihiUon cj Bliclrical Enginttn^ Part 91, vol. 
sx^ tBancoral Address by the Fresideat, William Crocket, F.R.S., 
|aa.i3tb»i89i. 



wave lengths given by the first formula, and greatly in- 
creasing the accuracy of the results. 

Wave-: 

leogth. Intensity. 

7005*5 5 A red line, seen in all the samples of gas. 

Young gives a chromospheric line at 

7o65'5. 
6678*1 8 A red line, seen in all the samples of gas. 

Thal^n gives a line at 6677 <^nd Lock- 

yerat6678. Young gives a chromO' 

spheric line at 6678*3. 
5876 30 The charaaeristic yellow line of helium, 

seen in all the samples of gas. Thal6n 

makes it 58759, and Rowland 5875-98. 

Young gives a chromospheric line at 

.^ 5876. 

5062*15 3 

5047*1 5 A yellow.green line, only seen in " Helium 
Puriss." and in •• Brdggerite, R/» and 
**L.*' Thal6n gives the wave length 
as 5048. 

50x5-9 7 A green line seen in all the samples of 
gas. Thal6n gives the wavelength 
50x6. Young gives a chromospheric 
line at 50x5*9. 

49319 3 

4922*6 xo A green line, seen in all the samples of 
gas. Thal6n gives the wave-length 
4922. Young gives a chromospheric 
line at 4922*3. 

4870*6 7 A green line, only seen in " Uraninite, 
R." Young gives a chromospheric 
line at 4870*4. 

48473 7 A green line, only seen in •• Uraninite, R." 
Young gives a chromospheric line at 
4848*7. 

4805*6 9 A green line, only seen in " Uraninite, R." 
Young gives a chromospheric line at 
480525. 

4764*4 a There is a hydrogen line at 4764*0. 

4735*1 10 A very strong greenish blue line, only seen 
in •• Uraninite, R." 

4713*4 9 A blue line, seen in all the samples of gas. 
Thal6n's measurement is 4713*5. 
Young gives a chromospheric line at 
47»3*4« 

4658*5 8 A blue line, only seen in «« Uraninite, R." 

4579' X 3 A faint blue line, seen in ** Uraninite, R.** 
Lockyer gives a line at 4580, from cer- 
tain minerals. I can see no traces of 
it in the gas from Br6ggerite. A hydro- 
gen line occurs at 4580* x. 

4559*4 3 Young gives a chromospheric line at 
4558'9- 

A faint blue line, seen in " Uraninite, R.*' 
Lockyer gives a line at 4522, seen in 
the gas from some minerals. Young 

fives a chromospheric line at 4522*9. 
t is absent in the gas l\rom Brdggerite. 
A blue line, seen in •• Uraninite, R," but 
not in the others. It is coincident with 
the strong head of a carbon band in the 
COa and Cy spearom. 
There is a hydrogen line at 4498*75. 
A very strong blue line, having a 
fainter line on each side, forming a 
close triplet. It is a prominent line in 
all the samples of gas examined. Young 
gives the wave-length 4471 8 for a line 
in the chromosphere, and Lockyer 
gives 447X for a hne in gas from Brog. 
gerite. 
44357 9 Seen io ^ HeUom Purist*" 
4437' I X Young gives a chromospheric liae at 
4437^. 



4544-1 
4520*9 



45"H 



4497*8 
447«'5 



3 
XO 



88 



Spectrum of Helium. 



I Sbbmical RIWSi 

I Aug. 23. 1895. 



Wave- 
length. 



Inteotity. 



4428'X 10 
44240 10 

4399*0 10 



43863 



4378-8 

4371-0 


8 
8 


4348-4 


10 



4333*9 10 



42987 



4281*3 
4271-0 


5 
5 


4258*8 
4227*1 


7 
5 


41986 
41899 

4i«i*5 


9 
9 
9 


4178-1 


X 


4169-4 
4157-6 


6 

8 



4143-9 



4xax-3 


7 


404**3 


9 


4026* X 
4024-15 


xo 
6 


40x2*9 
40092 
3964-8 


7 

7 

10 


3962*3 
39482 


4 

10 



3925*8 
3917*0 
3913-2 



These two lines form a close pair. I can 
only see them in •• Uraninite, R." No 
trace of them can be seen in the gases 
from other sources. Young gives 
chromospheric lines at4426 6 and 4425*6. 

A strong line, only seen in ** Uraninite, 
R.'* Absent in the gas from the other 
sources. Lockyer gives a line at 4398 
in gas from certain minerals. Voung 
gives a chromospheric line at 4398-9. 

Seen in all the samples of gas. Young 
gives a chromospheric line at 4385*4. 

{These two lines form a pair seen in 
** Uraninite, R," but entirely absent in 
the others. 

Seen in " Uraninite, R." Lockyer finds 
a line at 4347 in the gas from certain 
minerals* 

Probably a very close double line. Seen 
in " Uraninite, R '* and •• Cleveite, R." 
Not seen in the other samples. Lock- 
yer gives a line in the gas from certain 
minerals at 4338. 

Only seen in "Uraninite, R.*' Young 
gives a chromospheric line at 4298*5. 

Only seen in " Uraninite, R." 

Only seen in " Uraninite, R." The 
strong head of a nitrogen band occurs 
close to this line. 

Seen in all the samples of gas. 

Only seen in ** Uraninite, R.*' Young 
gives a chromospheric line at 4226*89. 

1 These three lines form a prominent group 
in «• Uraninite, R," they arc very faint 
in " Cleveite, R,** and in ** Brdggerite, 
L,'' but are not seen in *• Brdggerite, R." 

An extremely faint line. Lockyer gives 
a line at 4177, seen in the gas from 
certain minerals, and Young gives a 
chromospheric line at 4179*5. 

Seen in <* Helium Puriss.'* 

A strong line in ** Uraninite, R,'* very 
faint in " Brdggerite, R," and »* L,*' not 
seen in " Cldveite, R." 

Strong in "Cleveite, R," in "Helium 
Puriss.," and in ** Broggerite, L.** 
It is faint in ** Uraninite, R,'* and not 
seen in "Brdggerite, R." Lockyer 
gives a line at 4145 in gas from certain 
minerals. 

Present in all the gases except " Cleveite, 
R." 

Present in " Uraninite, R," and "Cleveite, 
R." Absent in the others. 

(These lines form a very close pair, seen 
in all the samples of gas, except 
"Brdggerite, R." Lockyer finds a 
line in Brdggerite gas at 4026*5. 

Seen in all the samples of gas. 

Seen in " Helium Puriss." 

The centre line of a dense triplet. Only 
seen in •• Cleveite, R," in •• Helium 
Puriss.," and " Brdggerite, L." Hale 
gives a chromospheric line at 3964. 

Seen in all the samples of gas. 

Very strong in " Uraninite, R,*' very faint 
in "Cleveite, R," and noTseen in the 
others. Lockyer finds a line in gas 
Irom Brdggerite at 3947. There is an 
eclipse line at the same wave-length. 

Seen in " Helium Puriss." 

Seen in " Helium Puriss." 

Only seen in ** Uraninite, R," and 
" Helium Purisa." Hale gives a 
chromospheric line at 3913*5. 



Wave- 
length. 



38905 
3888*5 

3885-9 

38746 
3867*7 
3819-4 

3800-6 
37325 

3705-4 

3642-0 

3633*3 
36278 

3613*7 
35870 
3447*8 
3353-8 
3247*5 
3187-3 



29449 

25365 

2479*1 
24464 
24x9*8 



Intensity. 

9 
10 

9 

6 

8 
10 



A very strong triplet, seen in all the 
samples of gas. Lockyer finds a line 
having a wave-length 3889 in gas 
from Brdggerite. Hale gives a chromo- 
spheric line at 388873. There is a 
strong hydrogen line at 3889*15. 

Only seen in " Uraninite, R." 

Seen in " Helium P4iriss." 

Seen in all the samples of gas. Deslandres 
gives a chromospheric line at 3819*8. 

4 Seen in " Helium Puriss." 

5 Seen in " Helium Puriss." Hale gives a 

chromospheric line at 3733*3. 

6 Seen in all the samples of gas. Deslandfes 

gives a chromospheric line at 3705*9. 
8 Only seen in " Uraninite, R." 

8 Seen in " Helium Puriss." 

5 Only seen in V Uraninite, R." 

9 Seen in " Helium Puriss." 
5 Seen in " Helium Puriss." 
8 Seen in " Helium Puriss." 
5 Seen in " Helium Puriss." 
2 Seen in " Helium Puriss." 

10 The centre line of a close triplet. Very 
faint in " Cleveite, R," and " Uraninite, 
R," and strong in " Helium Puriss." 
and in " Brdggerite, L." It is not 
seen in " Brdggerite, R." 

8 A prominent line, only seen in " Heliam 
Puriss." and in •• Brdggerite, L." 

8 Seen in " Helium Puriss." A mercury 
line occurs at 2536*72. 

4 Seen in " Helium Puriss." 

a Seen in " Helium Puriss." 

2 Seen in " Helium Puriss." 



Some of the more refrangible lines may possibly be dae 
to the presence of a carbon compound with the helium. 
To photograph them a long exposure, extending over 
several hours, is necessary. The quartz window has to be 
cemented to the glass with an organic cement, and the 
long-continued adion of the powerful indudion current 
on the organic matter decomposes it, and fills the more 
refrangible end of the spedrum with lines and bands in 
which some of the flutingt of hydrocarbon, cyanogen, 
and carbonic anhydride are to be distinguished. 

There is a great difference in the relative intensities of 
the same lines in the gas from different minerals. Be- 
sides the case mentioned by Professor Kayser of the 
yellow and green lines, 5876 and 50x6, which vary in 
strength to such a degree as to render it highly probable 
that they represent two different elements, I have found 
many similar cases of lines which are relatively faint or 
absent in gas from one source and strong in that from 
another source. 

Noticing only the strongest lines which I have called 
" Intensity 10," " 9," or " 8," and taking no account of 
them when present in traces in other minerals, the fol- 
lowing appear to be special to the gas from uraninite : — 

4735-1 
4658*5 
4428X 
4424*0 
4399-0 
4378*8 
437X-0 

4348*4 
4198*6 
4x899 
4x81*5 
4x57*6 
39482 
3642*0 



CHBafCALMlvt,! 
Aoc.as. 1895- f 



Helium and Argon. 



89 



The following strong lines are present in all the sam- 
ples of gas :— 

70655 
66781 
5876-0 
50159 
4922*6 
47134 
447«'5 
43863 
4258-8 
4012*9 
39623 

38905 
38885 

3885-9 
3819-4 
3705*4 

The distribution assigned to some of the lines in the above 
Tables is subjeA to corredion. The intensities are deduced 
from an examination of photographs, taken with very varied 
exposures ; some having been exposed long to bring out 
the fainter lines, and some a short time to give details of 
strudure in the stronger lines. Unless all the photographs 
have been exposed for the same time, there is a liability of 
the relative intensities of lines in one pidure not being 
the same as those in another pidure. Judgment is needed 
in deciding whether a line is to have an intensity of 7 or 
8 assigned to it ; and as in the Tables I have not in- 
cluded lines below intensity 8, it might happen that another 
series of photographs with independent measurements 
of intensities would in some degree alter the above 
arrangement. 

In the following Table I have given a list of lines which 
are probably identical with lines observed in the chromo* 
sphere and prominencies : — 



Vave-lengtht 




Wave-lengths of 


obsenredot 


lotendties. 


cbromotpberic lines,* 


beliam. 




Rowland's scale. 


70655 


10 


70655 


66781 


10 


66783 


58760 


30 


5876-0 


5015-6 


6 


50x5-9 


49"-6 


XO 


49223 


48706 


7 


48704 


4847*3 


7 


4848-7 


48056 


9 


480525 


4713-4 


9 


47»3-4 


4559'4 


2 


4558-9 


45209 


3 


4522-9 


4471-5 


XO 


4471*8 


4437' 


X 


44372 


4428-1 


XO 


44266 


44240 


XO 


44256 


4399-0 


10 


43989 


4386-3 


6 


4385-4 


42987 


6 


42985 


42271 


5 


422689 


4178-1 


I 


3^4-5 H.f 


39648 


XO 


3948-2 


XO 


3945-2 H. 


3913-2 


4 


3913-5 H. 


38885 


XO 


3888-73 H. 


3819-4 


XO 


3819-8 D. 


3732-5 


5 


3733-3 ^ 


3705-4 


6 


3705 9 D. 



* ** A Treatise on Astronomical Spedroscopy," by Dr. J. Scheiner, 
translated bj E. B. Frost, Boston, 18914. 

t Tbe wa¥e>leogths to wbicb the initials D. and H. are added are 
wave-lengths of lines photographically deteded in the spedrum of 
the cbromoapbere by Deslandres (D) and Hale (H). Their photo- 
graphs do not extend beyond wave-length 3630. Professor Lockyer 
(Roy. Soc, i'roc,, vol. Iviii., p. ti6. May, 1895) has already pointed 
out fourteen coiocidencea between the wave-lengths of lines in terres- 
trial beliam and in those observed in the chromosphere, the eclipse 
lines, and stellar spcdra. 



NOTE ON HELIUM AND ARGON. 
By Prof. H. KAYSBR, of Bocw. 

HiTHBRTo helium has been found only in a lew mineralt, 
and we do not know as yet in what atate it ezista there. 
It may therefore be interesting that I have found it in a 
free state in Nature. Some time ago I received informs* 
tion that in the springs of Wildbad, in the Black Forest, 
bubbles of gas rise up which— according to an old analysts 
of Fehling— contain about 96 per cent of nitrogen. As 
in all such cases it is possible that considerable quanti- 
ties of argon may be found, I submitted the gas to analjrsis. 
About 430 c.c. were mixed with oxygen, and sparks were 
caused to strike through it in presence of potassa-lye. 
Tbe excess of oxygen was then removed by means of 
potassium pyrogaUate. After desiccation there remained 
9 c.c, which were filled into Geissler tubes for a spedro- 
scopic examination of the gas. It showed the lines of 
argon and helium, the latter not in a small quantity, as 
its lines appeared very bright and could be readily photo- 
graphed. Range and Paschen have found that the gas ' 
evolved from deveite and broggerite is a mixture of two 
substances, one of which, helium, is most highly repre- 
sented in the visible spedrum by the yellow line Dj, 
whilst the other, not as yet named, is represented by the 
green line \ss^of6 fiji. Both these elements are also 
represented in the Wildbad gas, though it seems to me 
that the second element is here in a smaller proportion 
than in broggerite, as the green line is relatively feebler. 

In this result it seems to me especially interesting that 
thus for the first time a place has been discovered where 
the two gases included under tbe name '* helium ** are 
liberated and stream out into the atmosphere. Hence 
free helium must be found in the air along with argon. 
In fad, I have found in Geissler tubes which I had per* 
sonally filled with the purest argon possible, — and that at 
a time when I had not yet worked with heliumt so that 
no admixture with it could have occuned in my labora* 
tory, — on dired comparison with helium tubes the 
presence of D3 in the argon spedrum ; and I have ob- 
tained photographically the strong lines at 388*9 /i^. The 
lines are certainly veiy faint, but I consider the presence 
of helium in the air of Bonn ais beyond any doubc 
Whether this presence of pases in the springs of Wild- 
bad has any connedion with their hygienic efficacy, and 
whether the gases occur in similar springs, the future 
must show. 

Bono, Aognst 10, 1895. 



SYSTEMATIC ARRANGEMENT OF THE 

CHEMICAL ELEMENTS. 

By JULIUS THOMSEN. 

After D. Mendeleeff and Lothar Meyer, twenty-six years 
ago, had represented the properties of the chemical ele* 
ments as a periodic fundion of the atomic weights, the 
attempt was made to arrange the elements in a somewhat 
different manner, so that their periodicity might come to 
light as completely as possible. The original form which 
both Mendeleeff and Meyer employed in their tables for 
the exposition of periodicity contained the elements dis- 
tributed in groups of seven members (partly, also, of ten 
members), and the tables contained eleven such groups. 
But it soon appeared that this division of the entire 
number of elements did not present the desired periodicity 
in a fully satisfadory manner, and the tables were modi- 
fied in such a manner that only the two first groups re- 
tained each the number of seven members, whilst the re- 
maining elements were arranged in five groups each of 
seventeen members, but of these groups only the two first 
were approximately complete. But this form also had 
considerable defeds; it is especially difficult to find for 



go 



Systematic Arrangement 0/ the Chemical Elements. {^AuglV^^ i^T' 



EUctroposiiivi EUments 



H I- 




EUctroHegaiivt EUmtnts, 



the elements of the numerous rare earthi a place suitable 
to thecharaderof the entire svstem, since these substances 
are closely conneded, and their atomic weight fall very 
near together. 

The arrangement which I have used, and which is given 
in the following table, seems to me more satisfaAory. 

Few words only are needful to explain the significance 
of this arrangement. Hydrogen, as usual, forms the head 
of the table. The other elements are divided into three 
main groups, of which the first contains 2 + 7 elements, 
the second 2+17, and the third 31 elements ; after which, 
then, probably follows a corresponding series of 31 ele- 
ments, of which, as yet, only two elements are known 
(thorium and uranium). 

The first two groups, each containing two series, quite 
correspond to the arrangement now customary. But the 
table shows an essential difference in the collocation of 
the remaining elements in one series, beginning with 



eleAropositive csesinm and concluding with the metalt 
corresponding to the eledronegative members, hitherto 
known only as far as bismuth. A division of the elements 
of this group into two more classes is not possible if we 
wish to carry out the charader of the entire arrangement 
according to valence and eledrical charader. 

The tau)le shows in perspicuous manner the relationship 
of the elements. From hydrogen the lines coaneding the 
kindred elements lead, on the one hand, to the eledro- 
positive lithium, and, on the other, to eledronegative 
fluorine, and between these two members the other two 
members of the first series arrange themselves in the 
known manner. The members of the second series of the 
first group conned also in a known manner, each to a 
kindred member of the first ; but in the transit from the 
second to the third series, t.^., from the first to the second 
group, the division already observed in hydrogen repeats 
itself, each member of the second series being related to 



CsratoAt Rtwr, I 
Aug. aj, 1895. I 



Determination 0} Small Quantities of Arsenic. 



9* 



the members of the third ; that is, with one member be- 
longing to the eleAropositive part and another belonging 
to the eledronegative part of the third series. Thus, 
iodiam is related to potassium and copper, magnesium to 
calcium and zinc, aluminium to scandium and gallium, 
&c., and, lastly, chlorine with manganese and bromine. 
There then remain three members of the third series 
(iron, cobalt, and nickel), which form the transition from 
manganese to copper. 

The fourth series conneds itself in a known manner to 
the third, just m in the first group the second series con- 
neAt itself to the first. On the transition from the second 
to the third group a similar behaviour takes place as on 
the transit from the second to the third. Hence, also, 
the affinity of the elements appears to be demonstrable in 
two diredions ; partly in an electropositive and partly in 
an eledronegative dire^ion. Just as we are led from 
silicon of the first group on the one hand to titanium, and 
on the other to germanium of the second group, so pass the 
lines of affinity between the second and third group, #.^., 
from xirconium on the one hand to cerium with the atomic 
weight 140, and on the other hand to an element not 
definitely determined, with an atomic weight of about 
i8x. Between these two elements are grouped a great 
number of elements corresponding to the rare earths 
which all display a close relation, as also the intermediate 
elemenu of the third series from manganese to zinc. 

Many of the elements of the fifth series have onl;^ been 
partially investigated, and their nearest affinities in the 
fourth series cannot be indicated with certainty ; yet we 
tee various analogies among the better known elements. 
The table gives an indication, by means of dotted lines, 
such as that of cadmium and ytterbium (known by the 
pecaliar formula of the sulphate). 

The atomic weights in the table are carried to the 
nearest whole numbers, and are merely to serve as 
guides. 

Of the elements of the rare earths, I have included in 
the table all contained in the table of atomic weights pub- 
lished by F. W. Clarke (yourn. Amer. Chtm, Soc, 1894, 
«vi, 3). 

Finally, I wish to draw attention to a curious fad, t.#., 
that the number of elements in the single series, i, 7, 17, 
and 31, may be expressed by 1 + 2. 3 + 2. 5 + 2. 7. Prob- 
ably this occurrence of the prime numbers x, 3, 5, 7, is 
merely accidental. 

Although the table here given differs from the customary 
tablet only in its arrangement, I believe that it presents 
in a very perspicuous manner the fadts which may be de- 
duced from the periodic tytitta.—Ziitschrifi fUr Anorg, 
ChemUt ix., p. 190. 



QUANTITATIVE SEPARATION OF METALS 

IN ALKALINE SOLUTION, BY MEANS OF 

HYDROGEN PEROXIDE. 

By P. JAVNASCH and H. KAMMERER. 

I. Stparation of hianganisi and Silvir* 
For leparating thete two metals we put into a small 
beaker 0*7 to 0*8 grm. silver nitrate and an equal quantity 
of manganeae-aromonium sulphate, with 10 c.c. concen- 
trated nitric acid and the same volume of water. The 
•oluiton is pouted into a mixture of 20 c.c. water, 50 hy- 
drogen peroxide, and 40 concentrated ammonia, and the 
wbde is covered and heated upon the water-bath for ten 
to twelve minutes, whereupon the precipitate of hydrated 
manganeae peroxide, which rapidly deposits, is filtered 
off. The precipitate is most carefully washed, firstly with 
a mixture of 8 parts by voluipe of water, 17 of hydrogen 
peroxide, and 17 of strong ammonia, and finally with liot 
water, incinerated, and lastly ignited before the blast 
until the weight is coostant. The filtra.e. containing all 



the silver, is heated on the water-bath until the ammoni- 
acal odour disappears, acidified with concentrated nitric 
acid, an J the silver is separated as chloride in the ordinary 
manner. 

The separation of manganese and silver proceeds ex- 
tremely easily and smoothly. A single precipitation of 
the manganese is perfe^ly sufficient, as the precipitate on 
examination was found perfedly free from traces of silver. 
In more complicated mixtures, #. ^., an alloy of silver, 
bismuth, manganese, and nickel, the new process is de- 
cidedly to be preferred to a preliminary precipitation of the 
silver. 

2. Separation of Bismuth and Cobalt, 
As our initial material we used cobalt-ammonium sul- 
phate and pure metallic bismuth. About 0*5 grm. of the 
cobalt salt and 0*35 grm. bismuth are heated in a cruciblo 
upon the water-bath with xo c.c. concentrated nitric acid 
and 10 c.c. water until dissolved. In a second large por- 
celain capsule we have in readiness a mixture of ao cc. 
water, 50 hydrogen peroxide, and 50 concentrated ammo- 
nia, into which we pour the metallic solution after the 
addition of 10 c.c. concentrated nitric acid. After subai- 
dence the bismuth precipitate (still including traces of 
cobalt) is filtered off, and waahed first with a mixture of 
hydrogen peroxide and ammonia, as above, then with 
dilute ammonia (i : 2), and lastly with hot water. When 
this has been thoroughly done the precipitate is dissolved 
on the filter with hot dilute nitric acid (i : 3), noting the 
quantity thus consumed, and then add to the cold bia- 
muth solution so much concentrated nitric acid that ao c.c« 
of it may again be present in the liquid. The bismuth is 
then precipitated a second time exadly as before, the pre- 
cipitate washed precisely as above, dried at 90% incine- 
rated, and weighed as bismuth oxide in a platinum 
crucible. 

The precipitate, containing all the cobalt, is dried per- 
feAly on the water-bath, and then heated strongly in a 
large nickel air-bath until all the ammonium salts are 
expelled. The residual cobalt salt is now taken up with 
a little hot water, to which a few drops of hydrochloric 
acid and a little hydrogen peroxide have been added, di- 
luted to at most 100 c.c, and finally precipitated at a 
boiling heat with a slight excess of pure soda, with the 
simultaneous addition of some bromine. The precipitate 
obtained is well washed, dried, incinerated (the filter 
separately), and weighed as cobalti-cobaltous oxide. Or 
the cobalt may be diredly precipitated from the original 
ammoniacal solution with ammonium sulphide. This 
precipitate must be heated for some time on the water- 
bath until completely deposited, when it is filtered and 
washed with hot water containing ammonium sulphide. 
By the use of warm dilute aqua regia alternately with 
hydrogen peroxide, it is easily pradicable to re-diasolve 
the sulphide for the precipitation of the cobalt with toda 
and bromine.— B#mAr#, 1895, No. ix, p. X407. 



DETERMINATION OF SMALL QUANTITIES 

OF ARSENIC. 

By AD. CARNOT. 

We possess already numerous methods for the determina- 
tion of arsenic ; but these procedures, if convenient for 
large proportions, leave much to be desired in the case of 
slight quantities. But in a number of instances it is im- 
portant to determine the latter with accuracy. We know« 
for instance, that various metals — copper, iron, nickel, &c. 
— lose in part their industrial value if they contain a pro- 
portion of arsenic amounting to one part in a thousand. 
Great precision is also necessary for the determination of 
arsenic in mineral waters, where it sometimes plays a 
most important part, although its proportion scarcely ever 
attains some tenths of a m.grm. per Hue. 



Volumetric Estimation 0/ Nickel. 



I CBBMICAL KiBWt, 

1 Aug. 23. X895. 



The metbod which I am about to explain consists In 
precipitatinji: the arsenic in the state of sulphide, trans- 
forming the latter into arsenic acid by means of ammonia, 
silver nitrate, and hydrogen peroxide. The arsenic acid 
is then determined as bismuth arseniate, a compound very 
insoluble in dilute nitric acid, the weight of which is 
nearly five times equal to that of the element to be 
determined. 

The first operation is almost always the necessary com* 
plement of the treatment required for isolating the 
arsenic from other substances. According to the cases, 
the precipitation of the arsenic is effeAed either by the 
adion of sulphuretted hydrogen upon an acid solution 
where it is present as arsenious or arsenic acid, or by the 
decomposition by means of an acid of a solution in which 
the arsenic is present as a sulpho-salt. Hence the pre- 
cipitate is composed of a more or less important quantity 
of free sulphur. 

This mixtuie, after having been well washed, is treated 
with hot ammoniacal water; this readily dissolves the 
arsenic sulphide, leaving on the filter nearly all the free 
sulphur ; the surplus will be precipitated by the following 
operation :— We pour into the solution a sufficiency of 
silver nitrate, which produces a precipitate of silver sul- 
phide, and at the same time ammonium arsenite or 
arseniate, according as the precipitate contained arsenic 
trisulphide or pentasulphide. For the trisulphide, e^g., 
the transformation is represented by the following 
equation : — 

AsaS3+3AgaO.Na05-3AgaS.*.A8aOj-h3Na05. 

It is heated with stirring for some minutes to colledl the 
precipitated sulphide, and we satisfy ourselves that the 
liquid is not tendered turbid by a furher addition of a 
silver salt. We then add a few drops of pure hydrogen 
peroxide (or at least containing no other acid than the 
hydrochloric), which is without adion on silver sulphide, 
but which, at once, in presence of an excess of ammonia, 
converts arsenious acid into arsenic acid. 

We heat again to near loo^ until the odour of ammo« 
nia has totally disappeared, and we add a few drops of 
nitric acid so as to slightly acidify the liquid. We thus 
re'dissolve any silver arseniate which has been deposited 
on the expulsion of the ammonia, and we precipitate in 
the state of silver chloride all the chlorine which may 
be derived from an imperfed washing of the arsenic sul- 
phide at the outset, or from an impurity in the hydrogen 
peroxide employed. 

We co\\t€t on a filter the precipitates of silver sulphide 
and chloride, and, after washing, pour into the filtrate a 
nitric solution of bismuth subnitrate, containipg at least 
five or six times as much of this reagent as there may be 
arsenic in the substance under analysis. 

We saturate with ammonia, and allow to boil for some 
minutes. The white precipitate of bismuth hydroxide 
and arseniate is allowed to subside, and the liquor Is de- 
canted through a small tared filter. The precipitate on 
the filter and in the flask is then dissolved by water con- 
taining i/i5th of its volume of nitric acid at 1*310, and 
the solution is caused to boil. This degree of dilution is 
the most suitable for gradually dissolving the bismuth 
hydroxide and leaving the arseniate ccmpletely insoluble. 
Tl ere is formed a heavy crystalline precipitate, which is 
colleaed on the small tared filter, and washed first with 
water acidulated to ^\t and then with pure water. It is 
dried at xio% and weighed. 

The analysis of the precipitate leads to the formula— 
AsaOjBiaOs -*- HaO. 
It contains, therefore, in 100 parts, 21*067 of arsenic, or 
32*303 parts of arsenious acid. The precipitate must be 
weighed, diied, and not ignited, on account of the losses 
produced at a red-heat by the redudive adlion of the 
paper. A series of experiments prove that this method 
'^ veiy certain and accurate.— Cow^/^j Rendui, cxxi., 20. 



LONDON WATER SUPPLY. 
Report on thb Composition and Quality op Daily 
Samples op the Water Supplied to London 
FOR THE Month Ending July 31ST, 1895. 

By WILLIAM CROOKES, F.R.S., 

and 

PROFESSOR DBWAR, F.R.S. 

To Major-General A. De Courcy Scott, R.E., 
Watif Examimr, MitropoUs Water Act^ 1871. 

London, Angoit latb, iSgS' 
Sir, — We submit herewith, at the request of the 
Diredors, the jpesu|ls of diir analyses of the 189 samples 
of water colle6MdFby (is*flu^ng; the past month, at the 
several places and on the several days indicated, from the 
mains of the London Water Companies taking their 
supply from the Thames and Lea. 

In Table L we have recorded the analyses in detail 
of samples, one taken daily, from July zst to July 3xst 
inclusive. The purity of the water, in reaped to organic 
matter, has been determined by the Oxygen and Com- 
bustion processes ; and the results of our analyses by 
these methods are stated in Columns XIV. to XVIII. 

We have recorded in Table IL the tint of the several 
samples of water, as determined by the colour-meter 
described in a previous report. 

In Table III. we have recorded the oxygen required to 
oxidise the organic matter in all the samples submitted 
to analysis. 

Of the x8g samples examined one was recorded as 
** slightly turbid," and one as "clear, but dull;*' the 
remainder were clear, bright, and well filtered. 

July has been the wettest month since November Iast» 
when an excess of 2*49 inches of rain fell in the Thames 
valley. The adual amount of rain during the month just 
passed was 3*41 inches, and as the mean of 25 years is 
2*58 there has fallen an excess of 0*83 inch. With the 
exception of a heavy storm on the zst, the first half of 
July was dry ; after the ist scarely any rain fell till the 
i8th, the greater part falling between the i8th and 25th. 

The high level of purity of the Thames-derived waters, 
to which we drew attention in the report for June, was 
sustained in July, notwithstanding the fad that turbidity 
and peaty colouring-matters are always washed from the 
land into a river by heavy rain following a drought. A 
comparison of the chemical composition of the waters io 
July and in June shows that the constituents are almost 
identical in quantity. 

We have continued to examine the samples drawn 
from the clear water wells of the water companies at 
their works, and from the unfiltered river water. The 
unfiltered Thames water contained an average of 3425, and 
the filtered water at the works contained 30 microbes per 
cubic centimetre. 

We are. Sir, 

Your obedient Servants, 

William Crookbs. 
James Dbwar. 



THE VOLUMETRIC ESTIMATION OF NICKEL 
By THOMAS MOORE. 

In a former number of the Chemical News (lix., t6o, 
293) I described a volumetric method for the now indus- 
trially important metal nickel. A great many assays 
made by this process amply proved its reliability, and in 
this communication it is proposed to describe a modifica- 
tion by means of which ii is rendered one of the 
most exad processes in analytical chemistry. Those 
chemists who have employed the original method must 
have noticed that its weak place lay in the use of cupric 
ferrocyanide as indicator ; this, however, is now dispensed 



CataicAL Ntwt, 

Aof . aj, 189s 



I 



Report 0/ Committee on Atomic Weights. 



93 



with, and argentic iodide substituted. The principles 
apon which the process depends may be thus described : — 
li to an ammoniacal solution of nickel containing Agl in 
suspension (argentic iodide being almost insoluble in weak 
anunonia) there is added potassic cyanide, the solution 
will remain turbid so long as all the nickel is not con- 
verted into the double cyanide of nickel and potassium, 
the slightest excess of cyanide being indicated by the 
clearing op of the liquid, and, furthermore, this excess 
nay be exaAly determined by addins a solution of silver 
oDtil the turbidity is reproduced. It is a fortnnate cir- 
cumstance that the complicated sidereaAions existing in 
Parke's copper assay do not appear to take place with 
nickel solutions, at least not when the temperature is 
kept below ao^ C. This is fully borne out by the fad 
that the potassic cyanide may be standardised on either 
silver or nickel solutions with equal exadness. In 
pradice it has been found bett to proceed in the following 
manner : — 

Solution of argentic nitrate, containing about 3 grms. 
of silver per litre. The strength of this solution must be 
known with as much accuracy as possible. 

Potassic iodide, zo per cent solution. 

Potassic cyanide, 22 to 25 grms. per litre. This solu* 
tion must be tested every few days, owing to its liability 
to change. 

Standardising the Cyanide Solution, 

This may be accomplished in two ways : (a) on a solo- 
lion of nickel of known metallic contents, or (6) on the 
argentic nitrate solution. 

(a). First accurately establish the relation of the 
cyanide to the silver solution, by running into a beaker 
glass 3 or 4 cc. of the former ; dilute this with about 
150 CO. of water, render slightly alkaline with ammonia, 
and then add a few drops of the potassic iodide. Now 
carefully run in the silver solution until a faint permanent 
opalescence is produced, which is finally caused to dis- 
appear by the further addition of a mere trace of cyanide. 
The respedive volumes of the silver and cyanide solutions 
are then read off, and the equivalent in cyanide of i cc. 
silver solution calculated. A solution containing a known 
quantity of nickel is now required. This must have suffi- 
cient free acid present to prevent the formation of any 
precipitate, on the subsequent addition of ammonia to 
alkaline readion ; if this is not so, a little ammonic 
chloride may be added. A carefully measured quantity 
of the solution is then taken, containing about o'X grm. 
of nickel, and rendered distindly alkaline with ammonia, 
a few drops of potassic iodide added, and the liquid di- 
luted to 150 to 200 cc. A few drops of the silver solution 
are now mo in, and the solution stirred to produce a uni- 
form turbidity. The solution is now ready to be titrated 
with the potassic cyanide, which is added slowly and with 
constant stirring until the precipitate wholly disappears ; 
a few extra drops are added, after which the beaker glass 
is placed under the argentic nitrate burette, and this solu- 
tion gently dropped in until a faint permanent turbidity 
to again visible; this U now finally cansed to dissolve by 
the mere fradion of a drop of the cyanide. A corredton 
most now be applied for the excess of the cyanide added, 
by noting the amount of silver employed, and working 
onl its viuue in cyanide from the data already found ; this 
excess must then be deduded, the correded number of cc 
being then noted as equivalent to the amount of nickel 
MBmoyed. 

(k). Having determined the relative value of the potas- 
sic cyanide to the argentic nitrate, and knowing accurately 
the metallic contents of the latter, then Agx 0*27x96 
gives the nickel equivalent. This method is quite as 
accvrate at the dired titration. 

A modification of the above process, whereby one bu- 
rette only is necessary, has been found verv convenient, 
and has given most excellent results. It is based on the 
following :^Wben a solution of potassic cyanide, con- 
taining a small quantity of argentic cyanide dissolved in 



it, is added to an ammoniacal solution of nickel contain- 
ing potassic iodide, it is seen that argentic iodide is preci- 
pitated, and the turbidity thus cansed in the solution 
continues to increase up to the point where the formation 
of the nickelo-potassic cyanide is complete ; any further 
addition after this stage is reached will produce a clearing 
op of the liquid, until, at last, the addition of a single 
drop causes the precipitate to vanish* This final disap- 
pearance is most distind, and leaves no room for doubt. 
Such a solution ma^ be prepared by dissolving ao to 2$ 
grms. potassic cyanide in a litre of water, adding to this 
about 0*25 grm. arffentic nitrate previously dissolved in a 
little water. For urge quantities of nickel the quantity 
of silver may advantageously be diminished, and vic4 
versd. The value of the cyanide is best ascertained in 
the manner already described, on a nickel solution. 

Small quantities of cobalt do not seriously affed the 
results, but it must be remembered that it will be esti- 
mated along with the nickel; its presence is at once 
deteded by the darkening of the solution. Manganese 
or copper render the process valueless, so also does sine ; 
the latter, however, in alkaline pjrrophosphate solution 
exercises no influence. In the presence of alumina, 
magnesia, or ferric oxide, citric acid, tartaric acid, or pyro- 
phosphate of sodium may be employed to keep them in 
solution. The adion of iron is somewhat deceptive, as 
the solution, once cleared up, often becomes troubled 
again on standing for a minute ; should this occur, a fur- 
ther addition of cyanide must be given until the liquid is 
rendered perfedly limpid. The temperature of the solu- 
tion should never exceed 20° C. ; above this the results 
become irregular. The amount of free ammonia has also 
a disturbing influence ; a large excess hinders or entirely 
prevents the readion; the liquid should, therefore, be 
only slightly but very distindly alkaline. A word of 
caution must be given regarding the potassic cyanide, as 
many of the reputed pure samples are very far from being 
so. The most hurtful impurity is, however, sulphur, as 
it gives rise to a darkening of the solution, owing to the 
formation of the less readily soluble argentic sulphide ; 
to get rid of the sulphur impurity it is necessary to 
thoroughly agitate the cyanide liquor with oxide of lead, 
or, what is far more preferable, oxide of bismuth. 
. As regards the exadness of the methods, it is unneces- 
sary to give an array of figures. This much, however, 
may be said, that, after a prolonged experience, extending 
over many thousands of estimations, they have been 
found to be more accurate and reliable than either the 
eledrolytic or gravimetric methods, and when time is a 
consideration the superiority is still more pronounced. 
The employment of organic acids or sodic pyrophosphate 
in the case when iron, sine, dc, are present, allows us to 
dispense with the tedious separation which their presence 
otherwise entails ; and this is a matter of considerable 
importance in the assay of nickel mattes or German 
silver. 

Noomla, New Caledoaia. 



REPORT OF COMMITTEE ON ATOMIC 

WEIGHTS, PUBLISHED DURING 1894-* 

By F. W. CLARKB. 

To THi Mbmbsrs of thb Ambeicam Cbbmical Socxbty : 
Your Committee upon Atomic Weights respedfuUy sub- 
mits the following report, which summarises the work 
done in this department of chemistry during 1894. Al- 
though the volume of completed determinations is not 
large, it is known that several important investigations 
are in progress, from which valuable results may be ex- 
peded in the near future. It is in this country that the 

• From the Jourmat of the A mtncan Chemual Soeittyt vol. xvii.. 
No. 9. Rtad at the BoitOQ MMtim;, Dec aa. 1894. 



94 

greateal a^ivity exisU, and that the greatest progress is 
being made at present; and the preparation of these 
reports is therefore a peculiarly appropriate fundion of 
the Society. The data for 1894 are as follows : — 

The H : O ratio,^Kn interesting attempt at the indi- 
red measurement of this ratio, which is the base line upon 
which our system of atomic weights depends, has been 
made by Julius Thomsen (Zeit, Phys, Chem,, xiii., 398). 
His determinations are really determinations of the ratio 
NHj : HCl, and were conduced thus: — First, pore dry 
gaseous hydrochloric acid was passed into a weighed ab- 
sorption apparatus containing pure distilled water. After 
noting the increase in weight, gaseous ammonia was 
passed thronght to slight excess, and the apparatus was 
weighed a^ain. The excess of ammonia was then mea- 
sured by titration with standard hydrochloric acid. In 
ureighing, the apparatus was tared by another as nearly 
like it M possibl^ containing the same amount of water, 
Three sets of weighings were made, with apparatus of 
different size, and these Thomsen considers separately, 
giving the greatest weight to the experiments involving 
the largest masses of material. The data are as follows, 

HCl 
with the ratio jf^ in the third column. 



Report of Commit tee on Atomic Weights. 



* Cbkmical Nbws, 
t Aug, 23, l»95. 





First Series, 




Wt. HCl. 


Wt. NH,. 


RaUo. 


5*1624 


2*4x20 


2*1403 


3*9425 


1*8409 


2*14x6 


4*6544 


2*1739 


2*14x1 


3*9840 




2*1409 


5*3295 


2*4898 


2*1406 


4*2517 


1-9863 


2*1405 


4-8287 


2*2550 


21414 


6-4377 


3*oo68 


2*1411 


4-1804 


1-9528 


2*1407 


5*0363 


23523 


2*1410 


4*6408 


2*1685 
Second Series. 


2*14x1 


11*84x8 


55302 


2*14130 


14*30x8 


6*6808 


2*14073 


12*1502 


5*6759 


2*14067 


"•5443 


5*3927 


2*14073 


12-36x7 


5*7733 
Third Series. 


2*14118 


193455 


9*0360 


2*14094 


19*4578 


9*0890 


2*14081 



N = 14 and CI -35-5, it gives H = 1*0242; which is 
most unsatisfadory. In short, the method followed by 
Thomsen is too indired and subjed to too many possi- 
bilities of error to entitle it to much weight in fixing so 
important a constant as the atomic weight of oxygen. The 
dired processes, followed by several recent investigators, 
and giving O « 15*87 to 15*89 are much more trustworthy. 
Meyer and Seubert {Ber, d, Chem. Ges,^ xxvii., 2770 ; see 
also abstrad by Ostwald in Zeit. Phys, Chem., xv., 705), 
in their criticism of Thomsen's work, have pointed out 
some of its uncertainties. 

In this connedion it may be noted that Scott's research 
upon the composition of water by volume, cited by abstrad 
in the report of last year, has been published in full in the 
Philosophical Transactions , 1893, dxxxiv., 543. 

Strontium. 
The atomic weight of strontium has been re-determined 
by Richards {Proc. Amer. Acad.^ 1894, 369) from analyses 
of the bromide. The first ratio measured, after a careful 
preliminary study of materials and methods, was that 
between silver and strontium bromide. Of this ratio, 
three sets of determinations were made, all volumetric, 
but with differences of detail in the process. The weights 
are as follows, with the ratio Aga : SrBra : : 100 *. x in the 
third column :~ 

First Series. 



From the sums of the weights Thomsen finds the ratio 
to be 2*14087, or 2*13934 in vacuo. From this, using 
Ostwald's redudion of Stas*s data for the atomic weights 
of nitrogen and chlorine, he gets the ratio— 

O : H : : 16 : 0-99946, 
or almost exadly 16 : 1. In a later paper {Zeit. Phys. 
Chem., xiii., 726), Thomsen himself re-calculated Stasis 
data, with O » 16 as the basis of computation, and derives 
from them the subjoined values for the elements which 
Stas studied :— 

Ag 107*9299 

CI 354494 

Br 799510 

I 1268556 

S 32-0606 

Pb 206*9042 

K 39*1507 

Na 23*0543 

Li 7*0307 

N 14*0396 

Combining these values for chlorine and nitrogen with 
his ratio HCl : NH, he gels O : H :: 16: 0-9992. This, 
however, is only an apparent support of Prout*s hypo- 
thesis, for it depends on the aniiProutian determinations 
of Stas. If we calculate from Thomsen's new ratio with 



Wt. Ag. 


Wt. SrBr,. 


Ratio. 


«*30755 
210351 

2-23357 
536840 


1*49962 
24x225 

6*15663 


114-689 
114-677 
1x4-683 
114-683 


Sura 11-01303 


12-63003 


1x4-683 


1*30762 
2*10322 
4*57502 
536800 


Second Series. 
1*49962 
2-41225 


114*683 
114*693 
1x4*694 
1x4*691 


Sum 13*35386 


15*31577 
Third Series. 


1x4*692 


2-5434 
3*3957 
39607 
4*5750 


2*9x72 
3-8946 
4*5426 
5*2473 


114*697 
114*692 
114*692 
114695 


Sum 14*4748 


16*6017 


114-694 



From these data we have, if Ag a 107*93, and Br « 
79*955 iP ^ '6), the following results : — 

From first series .. •• Sr a 87*644 
„ second series •• 87*663 

„ third series .. •• 87*668 

In two additional series, partly identical with the fore- 
going, the silver bromide thrown down was colleded and 
weighed. I subjoin the weighings with the ratio 2AgBr : 
SrBra in the last column. 

First Series. 

aAgBr. BrBr,. Ratio. 

2-4415 16086 65*886 

2*8561 1*88x7 65*884 

6-9337 4*5681 65*883 



65*8834 



Sum 12*2313 


8-0584 


227625 
3-66140 
3-88776 
9*34497 


Second Series 
1*49962 
2*4x225 

2*56x53 
6*15663 


Sum 19' 17038 


12*63003 



65*881 
65*883 
65*887 
65-882 

65-883 



/ 



CBBMICAL NftW8,l 

Aof. 23, itk.5. I 



Chemistry of the Cyanide Process. 



95 



Frcm the firbt series •• 
,, second leries*. 



Sr 



87*660 
87-659 

The average of all five series is Sr « 87*659. 
(To b« cooUaaed.) 



REPORT OF EXPERIMENTS ON THE 

CHEMISTRY OF THE CYANIDE PROCESS, 

AND NOTES ON ITS WORKING. 

Nbw Process for Dbtbrminimg Cyanides. 

Solubility op Gold in Double Cyanides and in 

Hydrochloric Acid. 
Phbnolphthalbin as an Indicator in Titrating 

Potassium Cyanide.* 

By O. A. OOYDER, F.C.S., 

Aoalytt and Asuyer to the Sooth Aastralian School oi llinet 

and Indnstriet. 

(Oosdaded from p. 82). 

Another method of working the lixiviation process con- 
•ists in closing the draw-off pipe and filling the vat with 
water to the top of the filter bed ; the tailings are then 
filled in and levelled, and the strong solution run on. As 
the air cannot escape below it bubbles up vigorously 
through the solution, and appears to form channels in the 
tailings, which result in irregular percolation afterwards ; 
as the solution sinks, more is added from time to time 
ontil the vat is full, when a little of the water is drawn off 
from below, and the solution it then left standing for 
about twelve hours. The vigorous bubbling which takes 
place in the vat also causes the mixture of the strong 
solution with the residual water in the tailings, and thus 
increases its bulk. The solution displaced by weak liquor 
is ran off at a quicker rate than above, the rest of the pro- 
cess being the same as there described. Judging the two 
processes by the appearance of the solutions in the syphon 
bdtlet, the former process gave a clearer effluent with 
quicker changes from one solution to the other, and the 
aolatioo became colourless at the end with less wash 
water than the latter. As in the latter process the bulk 
of solution had already been increased at the begin- 
Ding the quantity of wash water at the end would have to 
be reduced, or the volume of solution would become un- 
manageable, and thus gold would be left in the tailings. 

The importance of the above, and especially of a 
thorough washing of the tailings after treatment by 

granide, is emphasised by an instance described by 
aldccott, Johannesburg Chem. and Met. Soc, July 28, 
1894, in which he says : — ** In the re-treatment of a mass 
ef residues by the African Gold Recovery Company, from 
which on the average 70 per cent of the original gold had 
already been extraded, the extraordinary fad was dis- 
covered that their value was no longer 15 dwts., but 
9 dwts. only. Explanations as to the reason of this dis- 
crepancy were sought for in vain, until, when all the 
residues had been re treated, the site they had occupied 
was sampled, with the result that the top 3 ins. was found 
to assay 38 dwts. of fine gold per ton, evidently derived 
from the soluble gold produced by the cyanide solution 
contained by the residues continuing to ad after dis- 
charge, and being washed downward by the rain." 

It is evident that the above was due to imperfed wash- 
ing. Whether the cyanogen compounds left in the tail- 
ings had already dissolved the gold when these were 
thrown out or afterwards dissolved it is quite another 
question ; but I believe the former was more nearly the 
case than the latter, as assumed by Mr. Caldecott. 

The time necessary for the lixiviation of a vat of tailings, 
Ac, varies from tweniy-four hours, where the gold is very 
fine and the solutions pass readily through tailings con- 
taining little injurious mineral, to a week or even a fort- 
night, where the gold is coarser, as in concentrates; but 
in any case I believe that, wheie possible, it is advan- 



tageous to let the solutions run through slowly and regu- 
larly,so that they will all pass in the least time necessary 
for the best payable extradion, reducing the strength of 
the solution and increasing its bulk where the gold is 
coarse, rather than to let the solution stand for some 
time in the ore and then run it off qnicklv. In the former 
case the solution is less liable to form channels, and the 
rate of flow between the coarse and fine interstices is 
more even than in the latter case. Also where the solu- 
tion is always moving fresh cyanide is being constantly 
brought into contad with the small particles of gold, 
whereas when the solution is standing all the cyanide 
near a small particle may soon become exhausted, and 
fresh cyanide is only able to approach to the attack by 
the very slow process of diffusion. In the experiments I 
have made on the small scale the slow even flow gave the 
best extra^ion in the least time, and no doubt it would 
be the same on the working scale. 

In the following Table the progress of lixiviation of a 
vat is shown by analyses of samples drawn from the 
syphon bottle at intervals of an hour, the solutions being 
allowed to run continuously, the whole process occupying 
less than twenty-four hours. The percentages of cyanide 
given were determined with the addition of excess of 
caustic soda, as above described, and therefore indicate 
cyanide of potassium plus cyanide of zinc and potassium 
plus some other double cyanides formed during the ex* 
tradlion, but not including ferrocyanide of potassium, or 
mercury, or copper-potassium cyanide. The strong solo* 
tion used contained 0*3 per cent of potassium cyanide and 
0*3 per cent of xinc-potassium cyanide, and the weak so- 
lution 0*3 of xinc-potassium cyanide. Both solutions 
contained between z dwt. and a dwts. of gold per ton re- 
maining from previous operations. 



Analysts of 
BoitU at 
of a Vat 

No.ol 

•ample. 



Samplis of Solution takin from Syfkon- 
Intervals of an Hour during the Lixiviation 
of Tailings, 



Appearance Per* 
10 syphon- eentage of 
bottle, cyanide in 
•ample. 



Gold per 
ton of Solatioo mo to 
•ample. 

Nil 1 Waste water 
Trace / tank. 
Owu. On. 



\ Small sine 
I boxes. 



X White Nil 

a White o'ooa 

3 '^^ti r<><>" 

4 "^ S^ 0*056 

5.. .. .. 2*1! oioa 

6 i m| ^ 0270 

8 « e o 0*424 

9 S-i ^'441 10 13 .L«fge line 

10 5 Jew 0499 6 la " boxes. 

" >.%%t 0*540 

13 ^^^l «*5oo 

14 ^i"S.^ <^*404 

15 1*2= ^ 0*302 

16 *S^i 0228 

17 °"rtS 0-200 

18 V %^'^ 0180 2 14 I Small sine 

19 ^- ^'^ o*'5o — I boxes. 

20 -S ^- S 0095 

21 j 0N 1^0*061 

Left draining.. — — 

I twill be noticed that the solutions do not pass as rapidly 
from one to the other as they should do. This is in con- 
sequence of the bottoms of the vats not sloping towards 
the draw-off pipe, and causing a mixture of the solutions 
in the vats. Had the vats been properly construded in 
this respeA I believe the water, at the commencement, 
could have been run off for another hour or more before 
the gold appeared, and similarly at the end of the process 
No. 16 to 18 should have shown 0*3 per cent cyanides, 
and the percentages then run down rapidly ontil not more 
than 0*005 should be contained in the tweilty«first hour, 



9 x8 

10 13 

6 la 

4 ao 

a 14 

■-'1 

a 6 



96 



Chemistry of the Cyanide Process. 



I ntBMICAL N BWt, 
I Aug. 23, ifcg5. 



while the gold in the same sample should not be more 
than a trace. It is also very evident that had the first 
two hoars* mnning been added to the cine boxes in addi- 
tion to another hour's running of water at full speed, not 
included in the table, the same amount would have been 
left in at the end, and that all the gold indicated from 18 
to 21 would thus have been left in the tailings in solution, 
or the bulk of solution duly increased. 

The next Table, which gives the result of a laboratory 
experiment, is not stridly comparable to the last one, as 
the ore was dry at the start and had not had the coarse 
gold removed by the battery. The bottom of the appa- 
ratus, however, sloped properly to the draw-off pipe, and 
it will be noticed how rapidly the strength of the solution, 
both in cyanide and gold, decreases after No. 15, when 
the wash -water began to appear, and on the large scale 
I believe it would decrease even more rapidly than this. 
The percentage of cyanide in the solutions was determined 
by the ordinary process, without the addition of caustic 
alkali. It will be noticed that the solutions contain rather 
more gold after standing than l>eforr, but much of the gold 
in this stone was much coarser than would obtain in an 
ordinaiy tailings, and a larger excess of cyanide was pre- 
sent than would be the case on the working scale ; 3000 
c.c. of cyanide solution, 0*2 per cent, was gradually poured 
on the ore, and was colleded in lots of 200 c.c. for ana- 
lysis. 

Analysis of Solutions running from Experimental Perco- 
lator during ihs Lixiviation of a Rich Sample con- 
taining Coarse Gold, 

Per cent of 
200C.C. cyanide ID Gold per ton in' Rematks. 

•ample. aample. 

OzM, Dwtt. Grt. 
!•• •• 0*044 490 

2., •• OTO3 5 16 O 

3.. •• 0-147 4 10 O 

4.. •• 0*165 3 I o Stopped and left 

standing 17 
hours. 
5.. .. o'i58 3 II o 

6.. .. o*i8o 260 Stopped for 46 

hours. 
7.. .. 0154 2 20 o 

8.. .. 0*172 2 12' o 

9.. .. 0-172 180 

10.* •• 0*172 o 19 o Stopped for 18 

hours, and 
wash • water 
added. 
II.. •• 0*145 o 12 o 

X2.. .. 0*154 o 6 12 

13.. .. 0-176 o 4 21 

14. • .. 0*165 o 4 21 

15.. .. 0*091 o 3 20 Wash- water be- 

gins to show. 
16 •• •• 0*015 o x8 Cyanide solu- 

tion nearly 
all gone. 
17,. •• 0*005 trace 

Some experiments were made at Mount Torrens to de- 
termine whether by allowing each lot of solution added 
to the tailings to drain away before adding more solution, 
and so causing the air to penetrate the tailings intermit- 
tently with the solution, a more perfeA extradion could 
be attained. As, however, the results were no better than 
by the usual method, and as unnecessary aeration pro- 
motes loss of cyanide, it appears better to add the solu- 
tions until the last wash water has been added as soon as 
the previous lot has sunk to the surface of the tailings. 

A sample of concentrates, mostly pyrites, received here 
for testing as to its suitability for treatment by the cyanide 
piocess, was found by a preliminary washing to contain 
so much ferrous sulphate as to decompose cyanide of 
potassium af the rate of about 150 lbs. per ton of con- 



centrates. After washing, however, 67 per cent of its gold 
contents were extracted without undue consumption of 
cyanide. In last year's report I alluded to the Eureka ore 
as requiring too much cyanide to be profitably treated by 
that process. The basic salts in this ore are not readily 
removed by washing ; but when the ore is passed through 
the battery these salts are so effeAually removed as to 
make the tailings readily amenable to treatment by cy- 
anide. A sample analysed by me contained about \ per 
cent of copper. W. R. Feldtmann {loc, cit.) recommends 
that where tailings require a preliminary wash before 
treatment by cyanide, that the washing should be done in 
a separate vat reserved for that process only, as ** when a 
water wash charged with acid out of the ore comes in 
contad with residual quantities of cyanide solution lying 
in the bottom and adhering to the sides of the tank, a cer- 
tain (quantity of hydrocyanic acid gas is liberated, which, 
diffusing through the whole tank, is capable of dissolving 
a not inconsiderable amount of gold from the ore ; such 
dissolved gold is not precipitated even if passed through 
zinc, and is consequently run to waste with the water 
wash.'* In this explanation Mr. Feldtmann appears to 
assume that the solvent adton of hydrocyanic acid on 
gold is at least equal to that of cyanide of potassium. As 
I have seen no records of experiments on this point I 
have just made one, placing a gold leaf in a bottle and 
adding 50 c.c. of i per cent cyanide of potassium, to 
which an equivalent of hydrochloric acid had just been 
added to set free the hydrocyanic acid : after being left in 
the bottom for four days, with occasional violent shaking, 
the solution was filtered off from the undissolved gold, 
and the gold dissolved was found to amount to 65 per 
cent of the whole taken. The solvent adion of hydro- 
cyanic acid on gold in the presence of air is therefore 
decided, but very slow. A solution of cyanide of 
potassium of 0*1 per cent would have dissolved the 
whole of the gold leaf under similar circumstances in 
about five minutes. 

Judging, however, from the complete removal of soluble 
salts from the Eureka ore in passing through the battery, 
it appears to me that with a sample of tailings containing 
deleterious soluble salts, and not requiring to go through 
the battery, these salts could be most effedually removed 
by passing the tailings over a shaking table, using plenty 
of water. 

The large quantity of cyanide of potassium decomposed 
by ferrous and other soluble metallic salts points to the 
advisability of transferring the tailings, and especially 
those containing pyrites, from the pits to the vats with 
as little exposure to damp air as possible, and also of 
testing the water running from the vats before the addi« 
tion of cyanide to ascertain whether a preliminary waeb 
is required. 

In order to ascertain whether the gold left in the 
tailings after treatment by cyanide could be extraded by 
further treatment, I procured from Mr. L. W. Grayson a 
sample from the tailings heap at Mount Torrens, and 
treated a portion of it with excess of i per cent cyanide 
of potassium by continuous percolation for forty-eight 
hours, thoroughly washing out the cyanide at the end. 
The tailings before treatment contained gold at the rate 
of X dwt. 13 grs. per ton, of which 8 grs. were extra^ed 
by the above treatment. The same sample was again 
treated in a similar manner by fresh solution, but only 
yielded i gr. per ton. The same sample was then treated 
with a large excess of strong bromine water during three 
days, percolating during the day and stopping with the 
percolator full during the night. During this treatment 
the small quantity of pyrites present was oxidised, bat 00 
gold was dissolved. 

The sample was then removed from the percolator, 
dried, and separated by sieves into three grades, which 
were assayed separately with the following result — the 
number of the sieves represent holes per linear inch : — 
Two per ctnt, retained by 3o-sieve, assayed 8 dwts. 3 gis. 
of gold per ton ; 29 per cent, retained by 6o-sieve, a&> 



CaiMICALMtWfil 



Chemtcal Notices from Foreign Sources. 



97 



•ayed a dwts. 7 grs. of gold per ton ; 69 per ceot, which 
pasMMi 6o-tieve» auayed 14 grs. of gold per ton, from 
which it was calculated that the gold would be divided as 
Ibllowt in a ton of the tailings : — Three grains of gold 
would be contained in 45 Ibt. of coarse tailings ; 17 ^. 
of gold would be contained in 650 lbs. of medium 
tailing!; xi grt. of gold would be contained in 1545 lbs. 
of fine tailings. 

Another sample treated in a similar manner yielded :~ 
ao'6 per cent, retained by 4o*Bieve, assayed 3 dwts. 7 grs. 
of gold per ton; ia*o per cent, retained by 6o-8ieve, 
assayed a dwts. of gold per ton ; 67*4 per cent, that 
passed 60-sieve, assayed x dwt. 4 grs* of gold per ton. 
Tbeiefore, 16 grs. of gold would be contained in 460 lbs, 
of coarse tailings ; 5 grs. of gold would be contained in 
ayo lbs. of medium tailings ; x8 grs. of gold would be 
cootained in X5X0 lbs. of fine tailings. 

Another sample of tailings which had been treated by 
cyanide contained 3 dwts. of gold per ton, and yielded 
I dwt. to further treatment as above by cyanide, and the 
gold remaining was equally distributed in the coarser and 
iner portions. 

It would therefore appear that this rebidual gold cannot 
be extraded by solvents without further comminution of 
the tailings, and must therefore be surrounded by matrix 
impermeable to the solutions. It is further evident that 
in the above-cited cases the tailings could hardly pay the 
cost of concentration, re-crushing, &c., necessary to ex- 
txMA some of the balance of the gold. 

During my stay at Mount Torrens in April, I inferred 
from the method in which the cyanide process worked 
that the double cyanide salts present in the sump liquors 
must have a considerable solvent adion on gold, and 
ibnnd on testing some of these sump liquors that they 
dissolved gold leaf at about a third of the rate of alkaline 
cyanide. After my return, therefore, I prepared some of 
these double cyanides and purified them by crystallisation, 
several times repeated, and found that zinc potassium 
cyanide dissolved gold in the presence of oxygen with the 
produdion of gold potassium cyanide and oxide of zinc ; 
part of the cyanide also appeared to be transformed into 
aorocyanide of potassium and auricyanide of zinc, zincate 
of potash being also produced thus :— 

K2ZnCy4-|-Au2+OaaKAuCyt+2nO, and 
4K«ZnCy4+4Au+30a- 

« Zn( AuCy4)a+ aKAuCy4+ 3Zn(0K)a. 

The cyanide of copper and potassium readed in a 
similar manner, but somewhat more slowly. 

The double cyanide of mercury and potassium does not 
appear to dissolve gold, even after four months* contad, 
with occasional shaking. This experiment, however, is 
not yet finished. 

I have not yet tested the double cyanide of calcium and 
potassium, which may be present in sump liquors from 
double decomposition, but probably it would be a better 
solvent for gold than the zinc double salt. 

Accordin|( to W. R. Feldtmann (Bngin4tr and Mining 
yaumalt Iviii., X894. ^'S* ^ig) the African Gold Recovery 
Company have made sone experiments recently, showing 
that zinc potassium cyanide has a solvent adion on gold 
in its ores and in the absence of any free potassium 
cjraoide. 

I have not yet had time to investigate the nature of the 
double salts formed in the lixiviation process apart from 
those formed in the zinc boxes, but believe there must be 
some double salt (or salts) formed which is more adive as 
a solvent for gold than the double zinc salt. Possibly it 
may l>e the double iron salt, KaFeCy4, but this is quickly 
converted by excess of cyanide of potassium into ferro- 
cyanide of potassium, which I find takes months to dis- 
solve gold leaf. I have not had time to determine the 
rcadtons involved. 

To the solvent adion of these double salts on gold, 
especially on ores containing copper or other ** refradory*' 
miAeials, the success of the cyanide process is without 
doubt to a large extent to be attributed. 



NOTICES OF BOOKS. 



Thi Chsmistry of Urim, A Pradical Guide to the Ana« 

lytical Examination of Diabetic, Albuminous, and Gouty 

Urine. By Alfred H. Allbn, F.I.C, F.C.S., Past 

President of the Society of Public Analysts, ftc. 8vo., 

pp. 3X2. London : J. and A. Churchill. X895. 

The author of this manual tells us that he has been led 

to take up thoroughly the chemical examination of urine, 

with especial reference to the requirements of physicians 

called on to ad as referees for Life Assurance Companies 

as well as in questions of diagnosis and prognosis, tience 

Mr. Allen has given special attention to the examination 

of diabetic, albuminiferons, and gouty urines. It has not 

been his objed to produce a complete manual of urinary 

analysis. 

The various methods for the scrutiny of urines are 
critically examined, and the conditions of their trust* 
worthiness or fallibility are carefully expounded. Hence 
the book will be of sterling value not merely to phjrsicians, 
but also to analysts, especially such as have not made 
this department of chemistry a leading study. 



Thi ConmUnct-MiUr^ Oirman PattnU No. 81,265. 

(Der Consistenz-Messer, D.R.P. 8x,a65). Berlin: 

Bernhard Paul. 
This pamphlet is in substance the very voluminous spe- 
cification of a German patent. The author, Dr. Weiss, 
has devised an instrument by which the amount of solids 
contained in an extrad, solution, &c., is estimated by the 
sinking of a suspended disc. Tne procedure is applied to 
fatty oils, solutions of gums, sugars, milks, t>eers, to 
the determination of starch in grain, in potatoes, seed* 
cakes, ftc. 

The general question arises, whether patents for 
any analytical or other scientific appliance are not ob- 
jedionable on the same principle as is a patent for an 
analytical procedure. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

NoTB.~AU degrees of temperature ate Centigrade ooless otberwist 
expressed. 

CompUs Rendm Htbdomadairts des Skances^ de VAcademii 
des Scientti. Vol. cxxi.. No. 4, July 22, 1895. 

Osmotic Phenomena produced between Ether and 
Bt hylic Alcohol, through different Diaphragms.—F. 
M. Raoult.— The author's experiments prove that the 
osmose between two given liquids may not merely vary 
greatly in ener^, but even change its diredion with the 
nature of the diaphragm, and that the osmotic naovement 
of substances through the diaphragm may be absolutely 
independent of their molecular weight and of their ftmdion 
as dissolved bodies or as solvents. 

Adion of Phenyl Isocyanate upon certain Acids 
and Ethers.-— A. Haller.— Not suitable for useful abstrac- 
tion. 

On Crystalline Anhydroua Manganese Hydrate.** 
A. Bourlot. — This paper will be inserted in full. 

Certain Properties of Compounds of Ferrous Chlor- 
ide and Nitric Oxide.— V. Thomas.— The author seeks 
to ascertain whether the compounds which he has recently 
obtained {Comptis Rendus^ Feb. 28th and July 8th, 1895) 
are or are not dissociable. He concludes from his experi- 
ments that none of the three compounds described has a 
tension of dissociation appreciable at the ordinary temper- 
ature. There is a very decided difference between the 



Chefnical Notices from Foreign Sources. 



I Chbhical News, 
• Aug. as. 1895. 



bmpounds obtained by M. Gay in the state of solution 
and thoie which the author has obtained by the dry way. 

On some Alkaline Phosphides.— C. Hngot.— The 
two phosphides P5K and P3K, the preparation of which 
he describes, are decomposed by moist air with disengage- 
ment of hydrogen phosphide. If an excess of ammonium 
is caused to an upon red phosphorus we obtain new com- 
pounds which the author is studying. 

Specific Heats of Superfased Formic and Acetic 
Acids. Modifications to be introduced into Reg- 
naolt's Thermo-calorimeter for the Determination of 
the Specific Heats of a great number of Superfused 
Liquids. — MM. Massol and Guillot.— The specific heats 
in the solid state are much higher than the specific heats 
in the liquid state. The specific heat in the liquid state 
decreases with the temperature. In the state of super- 
fusion the specific heat augments slightly. 

Synthetic Formation of Mixed Alcohols.— Louis 
Henry. — The reaaional capacity of methanal with nitro- 
methane, nitro-ethane, and nitro-isopropane corresponds 
to the number of hydrogen atoms enclosed in the carbon- 
itic system. 

-i- (NOa). 
I 
Oxidation of Inadive Campholenic Acid. — ^A. Behal. 
— Not suitable for abridgment. 

Constitution of Vegetable Albumenoid Substances. 
— E, Fleurent.— The failure of the proportion— 
N determined 

— — a I 

N calculated 
is due to the presence in gluten, caseine, and vegetable 
fibrine of a glutamine group, and in legumine and vege- 
table albumen of an asparagine group. 

No. 5, July 29, 1895. 

Adtion of Aniline upon Mercurous Iodide. — 
Maurice Francois. — The decomposition of mercurous 
iodide by aniline is limited, andjt is the same with the 
combination of mercuric iodide and mercury in presence 
of aniline. The author finds that when a state of equili- 
brium is reached the liquid always contains, at the 
boiling-point of aniline (iSa*), 26*35 &tas. mercuric iodide 
in 100 grms. of the mixture. The adion of aniline upon 
mercurous iodide is comparable to the adion of water 
upon bismuth nitrate, mercuric sulphate, ftc, studied by 
M. Ditte, and follows analogous laws. 

Adtion of Hyponitric Anhydride upon Campho- 
lenic Acid.— MM. A. B6hal and Blaise.— If we fix a mol. 
of NOa. and treat the blue liquid with a saturated solu- 
tion of potassium bicarbonate, there remains a blue 
insoluble oil, which soon solidifies. When re-crystallised 
from alcohol at 80° it forms slender blue laminae, fusible 
at 134*5, havine the composition CX0HJ5NO3. It is neu- 
tral, does not decompose alkaline bicarbonates, and may 
be obtained in two modifications, which may be named 
cemleonitrosocampholcnolide and leucooitrosocaropho- 
lenolide. 

The Condensation • ProduAs of Isovaleric Al- 
dehyd. — L. Kohn. — The author has obtained two pro- 
duds ; the one, boiling at 82** under a pressure of 15 m.m., 
seems identical with that studied by Kekul^, Fittig, 
Beilstein, and others, and probably with the produd ob- 
tained by Barbier and Bouveault. The second produd is 
an oil of feeble odour, colourless, boiling at 140° under a 
pressure of 18 m.m. It seems to be a polymer of valerol. 

The Determination of Boric Acid.— MM. H. Jay 
and Dupasquier. — This paper will be inserted in full. 

Ifevtie VnivcrselU des Mints et de la MetallurgU, 
Vol. XXX., No. 2. 
Tbii iiaue contaiai no chemical matter. 



MISCELLANEOUS. 

Responsibilities of Manufadurers in Germany. — 
The following remarkable decisions against employers 
have been lately given by the ** Reichs versicherungs 
Amt *' :— a. The death of a workman in consequence 
of drinking, at the Works, out of a bottle containing 
hydrochloric acid, in mistake for a bottle of " schnaps** 
which the deceased had brought with him. 6. Malicious 
poisoning by a fellow* workman, on the pretext that 
the quarrel was due to a disagreement over work. c. 
Injuries from the explosion of a dynamite cartridge 
which workmen on strike had left on the premises 
with criminal intent. d, A workman was over- 
whelmed with stones, &c.,in a quarry; afellow-workman, 
suffering from palpitation, was so excited that he died, 
e. In order to cure an injury to the fingers, received whilst 
at work, a labourer was sent by his employers to a medi- 
cal institute at Hamburg. Whilst there (in autumn, 
1892) he died of cholera, and his death was decided to be 
a working disaster. (Waich of these decisions is the 
most signally inequitable might be the subjed of a pro- 
longed discussion.) - Chimikir Ziitung* 

On Periodical Fludtuations of the Intensity of the 
Earth's Gravity, and their Influence on Determina- 
tions of Atomic Weights.— Dr. G. Paul Drossbach. — 
If a metallic cone with a very obtuse optical angle is 
brought in contadwith a mercurial horison, the slightest 
fluduations of the level of this cone must present the 
most different resistances conceivable to a quantity cur- 
rent. For the experiment the cone is suspended to a 
metal spring. The resistance varies from morning to 
evening, all accessory causes being of course taken mto 
account. The difference of gravitation was compensated 
by the addition of weights and thus diredly determined. 
The difference between morning and evening seems to be 
o'oo8 grm. per 100 grms. This indicates a speed of the 
movement of gravity of about 380 to 400 ni.m. The 
difference between midnight and noon seems to be 
rather greater, so that the maximum effed of gravitation 
falls at midnight and morning. — Chimikir Ziitung, 



DEPARTMENT OF SCIENCE AND ART. 
ROYAL COLLEGE OP SCIENCE, DUBLIN. 

Required a Demonstrator of Chemistry and 
AMaying.— For particulars apply to Sbckbtary. Royal Col- 
lege of Science, Doblin. 

HARRIS TnSTITUTE, PRESTON. 

Wanted, an Assistant to the Professor of 
Chemistry. A pra<ftical knowledge required of General and 
Agricultural Chemistry, with some experience in Analytical work. 
Salary, £100 a year. Applications, stating qualifications, and accom- 
paniel by copies of three Testimonials, to be forwarded before the 
ist of September, 1895, xo— 

T. R. JOLLY, Secretary. 

N OTICE. 

The STUDENTS* NUMBERof the Chemical 
News will be published on Friday ^ September 
6th, Gentlemen holding official positions in 
the Universities f Medical Schools ^ ^., of the 
United Kingdom, where Chemistry and Physi- 
cal Science form a part of the education, who 
have not yet forwarded the necessary informa- 
tion to our Office for publication in that 
Number, will confer a favour by sending it 
with the least possible delay. 

Advertisements for this Number should reach 
the Office not later than Wednesday^ th^ 
Sept. 



Ctmouti. 
A«(. JO, >I9S 



rtS^} Spectrum of Ramsay's Compound of Argon and Carbon. 



99 



THE CHEMICAL NEWS. 

Vol. LXXII.. No. 1866. 



THB SPECTRUM OF RAMSAY'S COMPOUND 

OF ARGON AND CARBON. 

By WnXIAM CROOKES. F.R.S., fte. 

In the Chbmical News for the and of Augait last (vol. 
honi., p. 51) Profetfor Ramsay aoDounced the probable 
esisteDce of a compound of argon and carbon formed by 
an eledric arc between purified carbon poles in an atmo- 
sphere of argon. Professor Ramsay kindly filled a quart- 
ended tube for me with the resulting gas at the requisite 
degree of exhaustion for the greatest luminosity, and I 
have taken several observations on its spedrum, both by 
the eye and photographically. 

The eye obeervations show an extremely luminous 
■peamm, in which many of the stronger lines of argon 
are visible. Measuremenu were taken of the following 
arfoo lines:— 



7646 


5909 


51858 


7506 


5887 


5165 


7058 


5834 


4879 


6965-6 


5803 


45095 


6664 


5771 


4335 


6407 


5651 


4272 


6173 


5610 


42595 


6045 


5557 


4201 


6038 


54965 


4159*5 



On comparing these with the extended table of the 
arfoo spedbrum given in the Chbmical News for August 
9th, it will be seen that they include all the strongest 
lines in the visible speArum. Others, less intense, would 
probably have been seen bad not the luminosity of the 
continuous spedrum interfered with vision. 

Examination of the photographs show that in the ultra- 
Ttolet portion of the spedrum there are also many argon 
lines, but a little above wave-length 3400 the strong lines 
diM to water-vapour interfere too much to allow the argon 
lines to be deteded. 

The higher portions of the visible spedrnm show 
finely channelled groups. These are very prominent 
in the photographs, and on superposing them on photo- 
graphs of beniene vapour, carbonic anhydride, and cyano- 
gen, taken under identical conditions, it is seen that the 
channelled bands are due to a carbon compound, the 
argon-carbon bands being identical with some of those 
of cyanogen and carbonic anhvdride, and not so strong. 

I have looked in vain for hues which are not in the 
argon, carbon, or water-vapour spedra, and have not 
Ibund any. . ^ 

The spedrum of water-vapour is due to moisture, the 

IS not having been perfedly dried before it was sealed 
J the tube. 

The argon lines are probably caused by excess of argon 
Mixed with the argon-carbon compound, the mode of 
Ibrmation making it very unlikely that all the argon had 
nnited with carbon. 

Professor Ramsay informed me that the nitrogen had 
all been removed from the aigon before it was sub- 
niued to the adion of the arc, and special precautions 
were also taken to remove occluded gases from the carbon- 

^Tbe coincidence of some of the bands of the new com- 
poond with those of cjranogen must not be used as an argu- 
nent in favour of the theory that argon is a condensed 
form of nitrogen. Most volatile compounds of carbon 
have very simuar spedra. If photographs of the spedra 
oC carbonic anhydride, carbonic oxide, bensine-vapour, 



Eu 



cyanogen, dc, are superposed, there will not only be seen 
a general resemblance between them, but in many of the 
systems of fluted bands there is absolute identity. All 
that can be said, therefore, is that the compound of argon 
and carbon gives a similar spedrum to that of most carbon 
compounds. 

I have looked in vain lor any line of helium in this 
spedrum. 

London, Aofvst 14, 1895. 



THB BLUE SPBCTRUM OF ARGON. 
Br Prof. H. KAYSBR. 

In the following Table I give a preliminary list of the 
wave-lengths of the lines of the blue argon-spedrum 
between X>b340 /i/a and X»52o /i/i. 

The gas was prepared from atmospheric air, first by 
copper and magnesium, then by sparking in the presence 
of caustic potash and absorbing the oxygen by pyrogallic 
acid and caustic potash. Finally, the gas wis dried by 
phosphorus pentoxide. At different times small quantities 
of argon were thus prepared, and many Geissier tubes 
filled at a pressure of 2*2 m.m., which seemed to give the 
best results. With a Leyden jar and air break a TOautiful 
blue light is produced. The spedrum was photographed 
with a large Rowland concave grating of 2X feet radius. 
The different tubes all gave the same lines, only one tube 
showed the hydrogen lines, and in another appeared the 
strongest lines of the red argon spedrum. I have photo- 
graphed also the red spedrum, which appears without a 
Leyden jar, but have not yet finished the measurement 
and calculation of the plates. The two spedra have no 
lines in common, as far as I see. 

For the calculation of the wave-lengths in every case 
the spark spedrum of iron was photographed at the 
same time on the plates, so that no shifting of the two 
spedra could occur. For the wave-lengths of the iron 
lines Rowland's standards were taken. 

The numbers in the Table are means of 3 to 6 inde- 
pendent measures ; the stronger lines may have an error 
amounting to o'oox /i/a. but the weaker ones are less ac- 
curate, and it is not impossible that in a few cases there 
may be an error of o*ox ><^ 10 signifies the greatest in- 
tensity, X the weakest. The lines of the blue argon 
spedrum do not appear among the Frauenhofer lines, as 
appears from a comparison with Rowland's publications 
on the lines of the solar spedrum. 

I shall soon add the red, yellow, and the remaining 
ultra-violet part of the blue spedrum, and also the red one ; 
then I shall also discuss these spedra for series. I wish 
only to state yet, that the red argon line at 7067 fifi is 
not coincident with the red helium line at 706*5 ^i/i, but 
has a greater wave-length. 



3454*291 

3464-387 
3466333 
3476*92 1 

3478385 
3480643 
349x019 
3491-420 

349«705 
34998x2 
3502342 
35037«5 
3509475 
3509-962 
35» 1-284 
35 "790 
35«4-354 
35x4-561 

3517*942 
3520x79 





3521-428 




3522098 




3535-517 




3545-778 




3546-0x6 




3548705 




3559707 




356x2x8 




3565-223 




35768x0 




358x804 




3582550 




3588634 




3592-23 X 




3606*072 
3622*362 






3638-025 




3640024 




3651x32 




3655-465 



2 
X 

3 
5 
5 

2 
8 

7 

a 
8 
4 
7 
9 

X 

2 
2 

7 

a 
I 
3 



lOO 



Separation of Gold and Stiver from Iron and Steel. { ' 



Aug. 30, 1895. 



3656*264 
3660*636 
3669632 

3678*476 
3680-075 

3692736 
3712963 
3716667 

3717316 

3718 393 
3720609 

3724563 
3729464 
3738-084 
3750-294 
3753768 
3756529 
3763718 
3765-461 
3766-3x7 
3770721 
3776885 
3781*022 
3786558 
3795*512 
3799-615 
3800-429 

3803383 
3808754 
3809645 
3825-831 
3826-983 
3830-603 
3841706 
3844-905 
3845536 
3850-721 
3858467 
3868700 

3872345 
3874288 

3875*4«3 
3880*432 

3891547 
3892-118 
3900750 
3907896 
3911-678 
3914-918 

3925897 
3928750 
3931-348 
3932705 
3937'2o8 
3944-4x2 
3946275 
3952-868 
3960-620 

3968499 
3974-662 

3979 5«7 
3992-208 

4013997 
4023730 
4034-0C9 
4035 630 
4038-968 

4043-047 
4053-118 
4072-158 
4072587 
4076-869 
4077207 
4079732 
4080-850 
4082553 



z 
I 

X 
2 
X 
X 
X 
I 
I 

3 
I 
I 
9 
3 

X 
X 
X 

3 
5 

2 
2 

X 

6 

2 

3 

2 

X 

2 
I 
3 

X 

3 

I 
I 

X 
X 

8 

2 
6 

2 

X 

3 

X 

2 
4 

X 
X 
X 

3 
3 
7 

X 

4 

X 

4 
3 

X 

2 
3 

X 

3 

2 
6 

X 

2 
2 
2 

4 
I 

7 
3 

2 
2 
2 
z 

X 



4089*041 
4ii»4-io2 
4112-915 
4131-919 
4x46*761 
4156-293 
4x78*477 
4179-478 
4183-109 
4199-226 
4202-1x5 
4203592 
4218-867 
4222848 
4227-142 
4228*30 X 

4229*059 
4229-874 

4237*397 
4266-385 
4275330 
4277-720 
4283*084 
4298-215 
4300-817 

4309*317 

4331-359 
4332-205 

4333-701 
4335*471 
4337-258 
4343-912 
4345-330 
4348*231 

4352-374 

4362*240 
4367*963 
4370-92X 

437i'504 
4375*266 

4376*129 
4379-832 
4383*900 
4400*269 
4401 *x65 
4408*102 
4421*102 
4426-170 

4430-365 
4431*176 
44340x0 
4439-541 
4443-545 
4449-128 
4460*683 

4475035 
4482-000 
4498874 
4503*099 
4545-231 
4579-531 
4589087 

4609750 
4658-070 
4727*032 
4736069 
4765*030 
4806' 185 

4847965 
4897*997 
4965-234 
5009*615 
50X7-42X 
5062-258 
5145-659 
Bono, July la, 1895. 



I 

7 
I 

4 
I 

2 
I 
I 
2 
I 
2 
1 
3 

3 

2 

5 

X 
X 

3 

6 

X 

6 

3 
I 

2 
2 
6 

3 
2 

X 

I 

2 

I 

10 

4 

2 

X 

4 
4 

X 

3 
6 

2 
3 
5 

X 
X 

9 
6 

4 

2 
X 
I 
2 
2 
2 

5 

X 

I 
5 
5 
5 
6 

4 
4 
5 
3 
6 

3 

4 

2 
2 
X 
2 
2 



ON THE PRODUCTION OF CITRIC ACID 

FROM CANE-SUGAR. 

(Second Note). 

Br Dr. T. L. PHIPSON. 

When I published my recent note on this sabjeA I should 
have remarked that Prof. Maumen6 {CompUs Rtndus, 
April 8, 1895) had already obtained two new organic acids 
by the a^ion of permanganic acid on cane-sugar ; and 
that Liebig formerly announced that he had obtained 
tartaric acid by the adion of dilute nitric acid on sugar. 

I have found that in the grape, the apple, &c., these 
acids disappear as the sugar is formed, from the outside 
to the inside of the fruit, and that the remaining acid is 
concentrated around the seed, probably aAing as an anti- 
septic until germination ensues. It is thus evident that 
organic acids are formed in fruits before the sugar it 
formed, and that the sugar may possibly be derived from 
them. Nevertheless, the ease with which sugar is con- 
verted into carbonic acid, formic acid, oxalic acid, &c., 
and its original produAion from the starch of the seed 
during germination, points to the possibility of all other 
organic acids devoid of nitrogen being obtainable from 
sugar. 

In treating cane-sugar in the cold with permanganic acid 
as described in my first note, I obtained an acid having 
some resemblance to citric acid, but no sufficient quantity 
was obtained to prove its real nature, and I have since 
been unable to repeat this experiment, but hope to do so 
shortly. I found, however, that other acids are liable to 
be formed at the same time, according to the degree to 
which oxidation is allowed to proceed. 

Some chemists who have repeated my first experiment 
have only succeeded in obtaining sulphate of lime. Pro- 
bably they used too much sulphuric acid, and did not 
separate the organic acid by alcohol as I did. 

The Cau Mia Laboratory, Putney, 
London, Augutt 20, 1893. 



SEPARATION OF GOLD AND SILVER FROM 
IRON AND STEEL. 
By H. N. WARREN, Retearch Analyst. 

To make an accurate and complete analysis of either iron 
or steel, as is well known, frequently requires a consider- 
able quantity of the sample under examination to become 
dissolved or otherwise aded upon, in order to ascertain 
the various constituents present, which are otherwise 
rendered latent by the large excess of iron associating 
them. But cases are few and far between where 4 lbs. 
in weight have to be operated upon, as was the case last 
week at the Research Laboratory, when an extraordinary 
examination was required in order to ascertain the relative 
amounts of both gold and silver present. For examina- 
tion and estimation of stiver 4 lbs. in weight of each 
sample were seleded, the produA being bar iron of one 
inch circumference ; each bar was attached to the posi- 
tive of a battery of 3 volts 40 amperes, whilst a carbon 
eledrode furnished the negative, dilute vitriol being 
employed as the solvent. Dissolution was completed in 
forty-eight hours, save a thin wire of iron, which was 
allowed to remain in order to ensure retention of the 
silver present in the carboniferous residue. 

The residue was next dried and intimately mixed Mrith 
an excess of chemically pure litharge and reduced in the 
usual way. The silver separated by cupellation, and gold 
by parting. 

Of the four samples thus treated, the stiver, being esti- 
mated as percentage of the carboniferous residue, 
amounted to as follows: — Iron of Swedish origin, 0*8; 
silver from Shortridge and Howel, 0*055 t ^^ Moor iron, 



CSBMICAl. MBWS, I 

Anc. so, 1895. I 



Reform in Chemical, Physical^ and Technical Calculations. 101 



o'loo; Dannemora, 0*064; i° c^ch case traces of gold 
were obtained by partiofi;. 

BarB of steel Bimilarly treated yielded percentages 
approximating o 078, 0*043, 0*098, 0*032. 

Liverpool Resemrch Laboratonr, 
i8,Albioo Street, £vertoo, Liverpool. 



GRADATION IN PRESSURES. 
By Dr. L. C. LEVOIR. 

Thb principle of gradation in pressures, ntilised in so 
prolific a manner by Cailletet, in condensing such gases 
ma oxygen and hydrogen, is useful in organic chemistry 
for saving the life of sealed tubes and viduable prepara- 
tions. 

** Krakatooing *' was the term which my students used 
when in the Bomb Room sealed tubes in the apparatus of 
Carius, &c., fell to ruin. Bursting can easily be prevented 
by heating the sealed tube by means of a coil glowing by 
ele^ricity. The condudor passes through isolated plugs 
hermetically sealed in inward conical tubes. By a 
hydraulic pump the pressure outside of the sealed tube is 
iacreased. I used a series of ends of boiler tubes, and 
they worked as a vault or arch to charge or burden the 
breakable tube outside. In this way, in five successive 
small boilers, and the coiled tube in a vessel of earthenware 
without bottom, rolled in vulcanised indiarubber cloth, I 
have saved the lives of many tubes. I heated water satu- 
rated at o* with hydrochloric acid to 250° without loss. 

Ryevidc sear The Hague, 
Augnet 10, 189s. 



A REFORM IN CHEMICAL. PHYSICAL. AND 
TECHNICAL CALCULATIONS. 
By C. J. HANSSBN, C.E. 
(Oootiaaed from p. 9). 

Evaporation of Wattr {Steam). 
Ip water is heated in a hermetically closed vessel, the 
•team produced is under the condition ** constant 



volume.*' In the working of steam boilers, this is only 
the case while a boiler is started or ** fired up,'* or during 
interruptions of the working ; in boilers in regular work 
the steam flows out as fast as it is produced, and the 
quantity of water in the boiler and the quantity of heat 
stored up in the water fismain unaltered, although new 
water is fed into the boiler to make ap for the water 
passing off as steam. 

The quantity of heat required to evaporate i kgr. of 
water, and which passes away with that i kgr. of steam, 
has only passed from the fire through the water stored up 
in the boiler; and to find the quantity of heat theoreti* 
cally required to produce i kgr. of steam, of any desired 
density, we have only to ascertain how much heat that 
I kgr. of steam is able to contain. The specific heat of 
water at various temperatures has no influence in the 
question, and has only to be considered if we were to 
ascertain the exaA quantity of heat required to ** fire ap *' 
a boiler. 

In a boiler in regular working the condition is " #va* 
f oration at constantprissun,** just the same as evaporation 
in an open vessel would be if the atmosphere of our globe 
had the pressure or density existing in the steam boiler; 
and the temperature of saturated steam in a boiler is 
equal to the temperature at which water would boil in an 
open vessel, in an atmosphere equal in density to that 
in the boiler. 

Although steam, for praAical purposes, is generated by 
the evaporation of water, it is useful for the mvestigation 
of its properties to consider the produdion of stesm by 
combination of hydrogen and oxygen, which enables us, 
in a very simple way and more accurate than by experi- 
ment, to find volume, weight, pressure, and other proper- 
ties of steam, due to any temperature, &c. 

In the former chapters it is shown that z cbm. steam of 
atmospheric density and 273° N. absolute temperature 
(0° N.), formed of combined H and O, must weigh 45/56 
kg., that I kg. of similar steam is » 56/45 cbm. in volume, 
and that heated to 373^ N. absolute (+100* N.), the 
proper temperature of saturated steam of atmospheric 
pressure, the volume of i kg. of steam will be increased 



cbm. a 17002849 cbm.. 



56x573° . 2984 
45x273^ 1755 

and the weight of 1 cbui. of such steam will consequently 



Tablt 0/ Saturattd Sttam. 



Preunrt. 

Atmocpberes. 
0*0042 
0*010 
0050 
0*100 
0*200 
0*300 
0*400 
0*500 
0*600 
0*700 
0-800 
o'goo 
1*000 
2 000 
3*000 
4*000 
5'ooo 
6*000 
7*ooo 
8*000 
9'ooo 

XO'UOO 

15*000 
20*000 



Temperatnre. 

io'ooo 

-f lOUOO 

+33*960 

+46*000 

+ 59*997 

+68*328 

+ 76.327 

+ 81*940 

+86-592 

+90*591 

+94*091 

+97 '201 

+ 100*000 

+ 120*996 

+ «34*993 

+ 145*491 

+ 153*889 

+ 160*888 

+ 166*886 

+ 172*135 

+ 176*801 

•f 181*000 

+ 199*033 
+ 212*500 



Weight of 
I cbm. in kg. 

0003375 

0*007750 

0*035734 

0*00877 

0*13x76 

0*19281 

0*25120 

0*30903 

0*36604 

0*42235 

0*47808 

0*53333 

0*588137 

rii359 

1*61308 

2*09682 

2*56946 

303362 

3-49096 

3*94262 

4*38944 
483204 
697096 
9*03708 



Heat reqaired to 
Volame of ovaporAtc 1 kg. liqaid 
X kf. in cbm. water of o^ N. 
CaL 



Heat required to 
V X P. produce 1 cbm. of tteam 
from water of o* N. 
Calor. 



296*296 
129*003 
27985 

«4 54» 
7*590 
5*186 
3981 
3236 
2732 
2368 
2*092 
1*875 
X 7002849 
0.8 8 
0*620 
0*477 
0*389 
0*330 
0*286 
0*254 
0*228 
0207 . 
0*143 

O'XII 



606*700 
6x0*700 

616-888 

620*500 

624699 
627*189 
629*598 
631*282 
632*678 

633877 
634*927 
635 860 
636*700 

642*999 
647*198 

650*347 
652*867 
654*966 
656*766 

658*340 
659740 

661*000 
666*410 
670*450 



« 24444 

1*29003 

139925 

«*454t 
1*5180 

t*5558 

1-5924 

1*6180 

1-6392 

1*6567 

1*6736 

1*6875 

1*7002849 

1*7960 

1*8597 

1*9080 

1-9460 

1*9776 

2*0048 

2*0312 

2*0502 

2*0696 

2*1510 

2*2 1 20 



2*04658 

4*80377 

22*04264 

42 67230 

8230747 
120*93928 
X58-I5II8 
185*08x79 
231*58120 
267 68231 
3035X042 

339*12458 
37446665 
7X6*03X80 

«043*84457 
X363-45964 
x678*3o68o 
X987*xo798 

2293*08974 
259590064 
289609214 

3*93*4334 
46468807 
6059 X322 



102 Reform in Chemical, Physical, and Technical Calculations, <*l"y.",5r 





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Chbmical Nbws, I 
Ang. 30, 1895. f 



Physical Theory oj the Perception of Colours. 



i03 

00 the contrary, in the case of salts, complex spedra 
charaderistic of the chemical species, and due probably 
to the non-dissociated molecule. They vary therefore 
from one compound to another. This fad has been al« 
ready brought to light for salts, melted or dissolved, in 
numerous researches, especially those of A. Mitscherlich, 
Diacon, and Lecoq de Boisbaudrao. 

As a general method of investigation, and especially in 
the deteaion of the non-metals or in the examination of 
minerals, it is, in my opinion, really advantageous to 
make use of the condensed spark, the elements being 
always represented in it by the same rays, the principal of 
which are easily recognised at first sight. 

In the case of salts the non-condensed spark gives, on 
the other hand, precise and very sensitive indications for 
deteding the presence of certain compounds by means of 
the band spedra. 

It is, moreover, easy to suppress the condensation in 
the experimental arrangement employed. 

For these researches we may make use of all coils ; it 
is merely necessary to take condensers with surfaces much 
more considerable in proportion to the size of the coil 
than is generally done. For apparatus giving sparks of 
3 to 5 cm. in length, I use two, three, or four Leyden 
jars, each surface of which presents about la square 
decimetres. 

It is curious to observe the effed of condensation upon 
the spark striking between eledrodes coated with free 
non-metals : if the spark is condensed, it gives fine line- 
spedra of these substances without igniting them ; if not 
condensed, it kindles them immediately, giving a conti- 
nuous spedrum scarcely visible. This experiment is par- 
ticularly striking with sulphur, arsenic, and selenium. — 
Comptts Rindust cxzi., p. X2Z. 



-~g^ kg. -0-5881367 kg. 

From these data, other properties of steam may be 
Iband by the following simple equations, where in all 



V denotes the volume of x kg. steam of any pressure in 
cbm. 

W denotes the weight of z cbm. steam in kilogrms. 

P denotes the pressure of steam in atmospheres abso- 
lute. 

T denotes the absolute temperature of steam in ^N. 



V X W 

8T 
1755 P 
'755 P 

8r 

8W 
1755 



» z 


5. 


-'75^5 P , X fN.) 


- V (cbm.) 

- W(kg.) 


6. 
7. 


^T .PxV (coeff.) 
1755 

-^ - V (cbm.) 


- P(cbm.) 


8. 


4- - w (»^«-) 



The accompanying Table gives, as a sample, a few of 
the results obtained by these formulae, which also, in 
diminished scale, are shown in the diagram, and which 
agree very closely with M. Regaault's experiments. 
(To be cootinned.) 

S$ Valdemartgade, Copenbagtto, V. 
July S3, 1895. 



ON THB 

DIRECT SPECTRUM ANALYSIS OF MINERALS 

AND OF SOME FUSED SALTS. 

By A. DB ORAMONT. 

I floucrr the Academy for permission to summarise the 
general resulu not only of the papers which I have al- 
ready had the honour of presenting, but also of researches 
which are now in the course of execution. 

A great number of minerals are sufficiently conducive 
or capable of volatilisation to give passage to the eledric 
•park between two of their fragments conneded resped- 
ively to the poles of an indudion>coil with a condenser 
intmalated. Under these conditions the spark produced 
behaves in the spedroscope like that of a metallic alloy, 
hot giving along with the rays of the metals contained in 
the mineral those of the non-metals with which they are 
combined. 

On suppressing the condenser the spedra of the non* 
metals disappear, and those of the metals are reduced to 
their most brilliant rays, showing out in general upon the 
laminous ground produced by the incandescence of the 
frasments. 

A certain number of melted salts, the study of which I 
have undertaken, especially the haloid salts, have given 
the same results, which may be generalised thus : — 

The condensed spark, playing on the surface of a com- 
pound, dissociates it, giving a line-spedrum generally 
very bright, where each substance — metallic or non- 
metaUio— is represented by the charaderistic rays of its 
individual spedrum. We have thus a composite spedrum, 
which may be considered as formed by the simple super- 
position of the spedra of its individual components. 

The raya of the air in the condensed spark are much 
•nleebled in presence of the volatilised elements, espe- 
cially when the explosive distance is very short ; they are 
then reduced, pradically, to the lines first signalised by 
Massoo. These atmospheric rays have even the advan- 
tage of serving as marks for the position of the micro- 
metric scale. 

Without a condenser and with the coil alone we have. 



ON A 

PHYSICAL THEORY OF THE PERCEPTION 

OF COLOURa 

By GEORGES DARZENS. 

In order to explain the perception of colours. Young, and 
subsequently Helmholta, admitted that each fibre of the 
optic nerve which enters into a cone of the retina is com- 
posed of three fibrils, one of which is strongly excitable 
by the red and little by the green and the violet ; the 
second strongly excitable by the green and little by the 
red and the violet ; and lastly, the third is strongly ex- 
cited by the violet and little by the red and the green. 

This hypothesis accounts for the existence of three 
elementary colours ; it equally explains a certain number 
of other fads, such as some peculiarities observed in 
dyschromatopsies, the phenomena of saturated colours, 
&c. But it is unable to explain many other fads not less 
important. Why should light having a wave-length of 
fi 0*620 strongly excite one of these fibres and have 
scarcely any effed upon the two others ? 

Here is a new theory of luminous perceptions which 
seems to me to agree better with the progress of physical 
optics and of physiology. 

A luminous ray, after having traversed the dififerent 
strata of the retina, impinges normally upon the pigment- 
ary layer of this membrane ; there it is refleded, and in- 
terferes with the incident ray. Hence we must have 
there in front of the pigmentary layer, and consequently 
in the adual thickness of the retina, a system of sta* 

. A. 
tionary waves distant by -, as in the experiments of O. 

Wiener, or in those of Lippmann on the photography of 
colours. It is further probable that these stationary 
waves can exist only in a feeble thickness, on account of 
the absorption by the medium which constitutes the 
retina. 



I04 



lUumination by Luminescence. 



f CasaicAi. NBWi, 
1 Aug. 30, t895- 



Let as remark, in passing, that this specalar faodion of 
the pigmentary layer exists in an unquestionable manner 
10 the ox, where it constitutes the ** carpet." These su- 
tionary waves excite the nervous terminations of the optic 
nerve. These terminations are of two orders, the rods 
and the cones. 

The rods being constituted by cylindric fibrils, resped- 
ively parallel, we can conceive that the stationary waves 
will excite them all, whatever may be their position — 
that is, whatever may be the X of the incident light. 
Hence we conclude that the rods give to the brain the 
general notion of light, without enabling us to judge of 
its colour. We know that the brain always conveys its 
excitements to the circumference, whatever may be the 
place where the nerve has been excited. 

The cones, on the contrauy, being formed of fibres, 
parallel,, but unequal in length, will be excited differently 
according to the X ; they will enable the brain to take 
account of the colour. 

These two conclusions are fully verified by experiment. 

It is known that we do not perceive all the colours well 
except by the central part of the retina (the yellow spot). 
Now it is there where the cones are found, the rods being 
turned towards the equator of the retina, which gives 
merely the sensation of light without the notion of 
colour. 

On the other hand, oodumal animals which do not 
distinguish colours have no cones, whtUt in birds which 
feed on coloured insets the retina is rich in cones. 

Finally, if this theory is correa, whenever the pigment- 
ary layer disappears, whether by old age or disease, 
there must result a parallel enfeebling of sight (a chroma- 
topsv). This is apparently confirmed by experience. 

This new theory can be brought to harmonise with 
the hypothesis of Young and Helmhohz. We need 
merely admit that the fibrils of the cones are divided into 
three groups proceeding to three different centres of 
perception. Still more, it explains why the wave-length 
which strongly excites one of these groups of fibrils must 
excite the other two groups feebly, it explains that 
curious arrangement of the retina when the excitable 
elements (cones and rods) are found placed in the deepest 
stratum, turned, so to speak, away from the side of the 
pigmentary layer which has hitherto appeared inex- 
plicable. 

It is remarkable to note that the procedure employed 
by the eye, in taking account of the wave-length of a ray 
of light, is quite comparable with the procedures hitherto 
employed by physicists. 

To me this theory appears satisfaAory to reason, since 
it reduces the perception of colours to the appreciation 
of a wave-length which is a magnitude of an order com- 
parable to the dimensions of the anatomical elements of 
the retina. It further seems to me to throw a clear light 
on the explanation of a number of the peculiarities of 
the eye. 

To dte merely a single instance, in the study of the 
achromatism of the eye we must no longer consider the 
retina as a simple screen like those of our laboratories, 
but a screen which perceives the different colours in 
different zones. — Comptn Rgndus, csxi., p. 133. 



ILLUMINATION BY LUMINESCENCE. 
By A. WITZ. 

Luminous foci are constituted by an incandescent solid 
or liquid, the temperature of which, according to Draper, 
must exceed iioo*^, in order that the light may be white 
and the speArum complete. The visible has for its 
boundaries the wave-lengths 0*38 and 076 /t, but the infra* 
red extends, so to speak, indefinitely towards the less re- 
frangible radiations, giving out a heat sensible to 
Laogle> 's bulumeter as far as to waves of the length of 



30 fi, and consequently including more than five odaves 
of luminous radiations. If we trace the curve of energy 
of the speara, plotting out the wave-lengths as abscissas, 
and the intensities of the radiations as ordinates, we find 
that it presents only a single maximum, situate generally 
at the beginning of the infra-red, but which is displaced 
progressively and advances towards the most refrangible 
region as the temperature of the focus increases. This 
curve is not symmetrical with reference to the maximum 
ordinate, and the greater part of its area lies on the side 
of the dark heat-spedrum. A large proportion of the 
energy belongs, therefore, to these invisible and hot radia- 
tions. This IS the reason why fod of light are all at the 
same time foci of heat, the photogenic yield of which is 
extremely slight. I have calculated this jrield in a paper 
inserted in the CompUs Rtndus (cxii., June 29, 1891). 

To improve this yield would be an important scientific 
discovery, and a great number of investigators have made 
it the objed of their researches. 

It has appeared to some that the solution of the problem 
might be furnished by luminescent foci, in which the tem- 
perature of the rarefied gas is, according to Herr Warburg, 
mcluded between ai° and 132°. These foci, it must be 
admitted, radiate but little light, but their thermic emis- 
sion is still more feeble. 

The luminescence of the tubes is effeded either by the 
high tension currents given by Volu-Faradaic induAion 
apparatus, or by the currents supplied by a Holts machine. 
In the former case we may determine the watts con- 
sumed in the tube; in the second case we measure 
the kilogrammeters expended to set the generating 
machine in aAion, both when at liberty and when 
burdened. 

I have experimented with several tubes, and especially 
with a lamp intended for miners and a tube for physicians 
(for illuminating deep cavities of the body). 

The lamp for miners is illuminated without difficulty by 
the induAion current of a small Ruhmkorff coil, yielding 
a spark of 20 m.m. ; it yields enough light to read a table 
of logarithms at the distance of 40 cm. from the source 
of light. Mr. Laogley has been content with this very 
rudimentary photographic measurement. The pale 
greyish blue tint oi the light does not lend itself to the 
methods of comparison used in photometry. I have found 
between the terminal electrodes a difference of potential 
of 4190 volts, the current having then an intensity of 0*27 
milliampere, which makes 1*13 watt. The energy con- 
sumed is large in comparison with the light produced ; 
we might hope for a better yield. 

The results obtained with a Holtz machine are more 
interestins. I have used Hirn*s Uansmission dynamo- 
meter to determine the work necessary to make the glass 
plate of the machine rotate 726 times per minute, under 
the following conditions : — 

Movement. 

^ * Sparks of 

CkMcd 145 m.m. Miner's Medical 
Free, circuit od 8 per iamp. tube, 
machine, second. 
Work per second 
in kilogrammeters 1*043 ^7^5 2*174 i'7iz 1*763 

Hence the illumination of the miner's lamp requires 
z*7xz — 1*043 vO'CCS kilogrammeters, or 6 6 watts. The 
yield is still less than that above. The incandescence of 
a lamp with a carbon filament in a vacuum only requires 
3 watts per candle. Our miner's lamp absorbs more 
energy and gives much less light — a ruinous method of 
lighting. Still the quantity of heat radiated is slight. 

Having plunged the medical tube into a calorimeter, 
we have observed a liberation of 0*00033 cal. per second, 
which corresponds to o 00033 x 425 as 0*140 kilogrammeter. 
Now, the illumination of this tube requires 0*720 kilo* 
gram metre, whence the heat produced corresponds only 
to the fifth part of the energy expended. From this point 
of view no other source of light gives so favourable a 
result. 



Cbbhical Mbws, I 
Ang. 90, 1895. I 



Report of Committee oft Atomic Weights. 



105 



The figures which we produce are evidently only a first 
approximation, since they vary with the nature and the 
form of the tubes employed, and have no absolute 
charader. But we may learn from our experiments that, 
in lighting by luminescence, the proportion of thermic 
energy with reference to the entire energy is smaller than 
in any other source of light. By reducing to a minimum 
the losses of eledricity, by concentrating the light in a 
limited space, by utilising the fluorescence of certain sub- 
stances, by inventing certain special arrangements, we 
may hope to obtain foci the photogenic yield of which 
will be ereater than that of our best sources of light. At 
present luminescence at low temperatures gives but very 
mediocre results, but at least enables us to reduce the 
invisible and useless portion of emission spe^ra. — Comptes 
RtnduSt cxxi., p. 306. 



ANG-KHAK, A CHINESE FUNGOID PIGMENT 

USED FOR COLOURING ARTICLES 

OF FOOD. 

By H. C. POINSBN. 

This colouring- matter is imported into Java from China, 
for giving a fine purple colour to foods and beverages. It 
is the produA of a special fungus which is propagated in 
the province of Quant-tuog for preparing the colouring- 
matter. Rice, thoroughly boiled, is spread out upon 
plates to cool, and when quite cold is sprinkled over 
with ang-khak of a former preparation. The plates, with 
itaeir contents, are then kept for six days in a dark, cold 
place. It then has a red colour, which afterwards be- 
comes darker. 

In what manner the Chinese obtained the first ang- 
khak fungi is unknown. The colouring-matter dissolves 
readily in alcohol with a splendid garnet-red colour. 
The lungus belongs to the group of the Telebolse. It 
vegetates upon any kind of carbohydrate in the presence 
of oxygen. The chief difficulty in its preparation is to 
keep away other fungi and baAeria, especially a species 
not yet examined. This is effe^ed by means of a trace 
ol arsenic, which prevents the growth of other baderia 
without interfering with the development of the ang- 
khak. 

The colouring-matter can be extraded with chloroform. 
In a state of purity it dissolves in methyl- and ethyl- 
ether, glacial acetic acid, aceton, and ethyl acetate, but 
very sparingly in water and dilute acids, and not at all in 
benzene, petroleum ether, oil of turpentine, carbon-disul- 
phide, and glycerin. It melts at 50% and at a strong heat 
It is decomposed without subliming. The alcoholic solu- 
tion displays a narrow absorption band at D, and a broad 
band in the blue between D and G. The colouring- 
matter behaves like most of the aniline colours, but it is 
distinguished by its precipitability with mercuric oxide. 

(The manufa^ure of ang-khak is probably the first 
instance of the technical use of microbia}.— C/i#miA#r 
Ziitung, 



PREPARATION AND PROPERTIES OF 

HYDRAZIN HYDRATE. 

By C. A. LOBRY dk BRUYM. 

Thb isolation of hydrazin hydrate without the use of 
•ilver vessels is effe^ed as follows :• 

The commercial Hydrate is first converted into the more 
readily soluble hydrobromic compound by means of 
barium bromide ; the precipitate is filtered off, and the 
filtrate is concentrated by evaporation and gradually 
mixed with the calculated quantity of concentrated 
potaasa lye. After the liquid has been dilated with an 



equal volume of alcohol it is allowed to cool ; the potas- 
sium bromide is filtered off with the aid of the pump, 
rinsing out with a little alcohol. The filtrate is distilled 
at ordinary pressure until the ebullition point reaches 
108°. We have thus the chief part of the base in the 
residue, in which potassium bromiJe further separates 
out on cooling. 

After filtration it is distilled at first at the ordinary 
pressure, and then at a pressure of i2Z to 122 m.m. Of 
the six fradions colleded the three last contain from 77 to 
97*5 per cent of hydrazin hydrate. To this mixture there 
is added, after heating to 50^, rather more than the cal- 
culated quantity of barium oxide to combine with the 
water present, when a strong heat is developed. After 
cooling there is added, to each 150 grms. of the hydrazin 
sulphate employed, 20 to 25 c.c. of absolute alcohol ; it 
is filtered and washed with a little absolute alcohol. The 
solution is then fradionaied at a reduced pressure, when 
about 22 per cent of the theoretical yield contains 997 
per cent of hydrazin hydrate, free from silicon. 

The boiling-point of hydrazin hydrate, at a pressure of 
26 m.m., is constant at 47°. There is no perceptible de- 
composition. In air free from carbonic acid, hydrazin 
hydrate is slowly oxidised with an escape of gas. The 
substance dissolves various salts, such as potassium 
bromide, iodide, and cyanide ; ammonia, sodium chloride, 
and salts of lead with difficulty, whilst potassium and 
zinc sulphates are scarcely taken up at all. Sulphur is 
gradually dissolved, even by dilute solutions; salts of 
lead gives a black deposit with the solution. 

On boiling hydrazin hydrate at 22*8 per cent with sul- 
phur the liquid takes a reddish-brown colour, whilst 
sulphuretted hydrogen escapes. From this solution sul- 
phur is thrown down, not by water, but by an excess of 
hydrochloric acid. Phosphorus ads slowly upon hydrazin 
hydrate, and an odour of hydrogen phosphide is given off. 
Sodium decomposes hydrazin hydrate with the formation 
of hydrogen and ammonia, and there separates out a 
crystalline substance soluble in water and alcohol. The 
solution of the substance gives the hydrazin reaAions. 
— Rte, Trav, Chim, dts Pays Bos and Chem. Zeitung, 



REPORT OF COMMITTEE ON ATOMIC 

WEIGHTS, PUBLISHED DURING i894.' 

By F. W. CLARKB. 

(Continued from p. 93). 

Barium. 
Richards has corroborated his earlier determinations of 
the atomic weight of barium, which were made with the 
bromide, by means of additional series of experiments 
upon the chloride {Proc, Amer, Acad., xxix., 55). The 
work was carried out in the most elaborate and thorough 
manner, and for details the original paper must be con- 
sulted. First, barium chloride was titrated with standard 
solutions of silver, and the several series represent dif- 
ferent methods of ascertaming accurately the end point. 
The data are as follows, with the ratio Aga : BaCla : : 100 :;r 
in the third column. 





First Strits, 




Wt. Ag. 


Wt. B«CI,. 


Rftdo. 


6 1872 
5-6580 
3-5988 
9*4010 
07199 


5-97>7 
5*4597 
3-4728 
9-0726 
06950 


96-517 
96495 
96499 

965 7 
96541 




Mean . 


. 965 '2 



* From the Journal of the American Chemical Society, vol. xvii., 
No. 3. Read at the Boston Meeting, Dec. 28, 1^94. 



io6 



Report of Committee on Indexing Chemical Literature. 



i Cbbhical Mbw», 
I Aug, 30. X895. 





Sicond Striis, 




6-59993 


6-36974 
5-360x0 

392244 


96-512 

96539 
96522 




Mean . 


• 96-5H 




Third SerU$. 




4-4355 
27440 
6-1865 
3-4023 


4-2815 
2-6488 
5-9712 
32841 


96-528 

96-531 
96*520 
96526 




Mean . 


• 96-526 




Fourth Siriif, 




67342 
10*6023 


6-50022 
10-23365 


96525 
96523 



Mean 



96524 



AU the weights represent vacaum standards. From the 
four series the atomic weight of barium is deduced as 
follows ; when O » 16. 

First series Ba » 137-419 

Second ,. •• .^ 137*445 

Third „ „ 137-449 

Fourth „ ,. 137*445 

In three more series of experiments Richards deter- 
mined the ratio between aAgCl and BaCla. The data are 
subjoined, with the ratio aAgCl : BaCIa : : xoo : x ap- 
pended. 

First Siriis, 



Wt. AgCl. 
8-7673 
5-«979 
4-9342 
20765 
4-4271 


Wt. B«CI^ 

63697 
37765 
35846 
1-5085 
3*2x63 


Rmtio. 

72653 
72*654 
72-648 
72*646 
72*650 




Mean 


.. 72649 




Stcond Siriis, 




2-09750 
7376x0 
5-39906 


1-52384 
5-360x0 

3*92244 


72-669 
72650 




Mean 


• • 72-6563 




Third Series. 




8-2189 
4-5x99 


5-97123 
3-28410 


726524 
726587 



Hence we have for Ba— 



Mean 



726555 



First series Ba » 137*428 

Second „ , 137*446 

Third „ 137*444 

The mean of all is X37'440, as against 137*434 found in 
the work on the bromide. By combining the two chloride 
ratios, Aga : BaCla and 2AgCl : BaCla. the ratio Ag : CI 
can be computed. This gives Ag » X07-930, a value 
identical with that of Stas. 

(To be continaed). 



Detection of Ergot in Bran. — The method of E. 
Hofmann, according to Ulbricht, is useless if bran con- 
tains the seeds of Polygonum convolvulus. The author 
finds that o 2 per cent of ergot, and even smaller (quanti- 
ties, can be deteded microscopically if the bran is pre- 
viously digested for two hours on the water-bath with 
sulphuric acid at 1*25 per cent, then with sodalye of the 
tame strength, and, lastly, treated in the cold with abso- 
lute alcohol and ether. — Zeit, Anal. C^ai.,sxxiii., Part 6. 



THIRTEENTH ANNUAL REPORT 

OF THE COMMITTEE ON INDEXING 

CHEMICAL LITERATURE.* 

Thb Committee on Indexing Chemical Literature pet- 
sents to the Chemical SeAion its Thirteenth Aoniisl 
Report. 

During the twelve months which have elapsed 
the last report the following bibliographies have 
printed: — 

X. ** Indexes to the Literature of Cerium and Lantha- 
num." By W. H. Magee. Smithsonian Miseelkmtous 
Collections, No. 97X. Washington, X895. 4.3 pp. 8vo. 

2. ** Index to the Literature of Didymtum, X842— 
X893.*' By A. C. Langmuir. Smithsonian Miscellaneous 
Collections, No. 972. Washington, X895. 20 pp. 8vo. 

These bibliographies of three associated metals fill an 
important gap in chemical literature. That by Dr. 
Langmuir is reprinted from the School of Mines Quarterly 
(vol. XV.), at the request of your Committee. Both 
indexes are arranged chronologically and provided with 
author-indexes. 

3. '* Bibliography of Aceto-Acetic Ester." By Paul H. 
Seymour. Smithsonian Miscellaneous Collections, No. 
970. Washington, x894. 148 pp. 8vo. 

This bibliography was compiled by the author under 
the diredion of Prof. Albert B. Prescott, and by him 
submitted to the Committee who recommended its pub- 
lication Aug. 22, x892. It consists of a series of carefully 
prepared, critical abstraAs of original papers arranged 
chronologically with author- and subjed-indexes. 

After issuing the twelfth Annual Report the attention 
of the Committee was direAed to two contribntioos to 
the bibliography of chemical and pharmaceutica I period- 
icals by Dr. Friedrich Hoffmann, editor of PAomui- 
ceutische Rundschau^ vis. : — 

4. *< Die Deutsch-sprachlichen pharmaceutischen Zeit- 
scriften.'* Pharm, Rundschau, New York, vol. xii., pp. 
7 — 10 (Jan., 1894), <^n<l P* 28 (Feb., x894). 

5. ** Enplish-sprachliche pharmaceutische, chemiscbe 
und botanische Zeitschriften Nord-Aroerika's.*' Pharm. 
Rundschau, New York, vol. xii., pp. X3X— X36 (June, *94). 

Several chemists have made reports of progress : — 

Prof. Henry Trimble, of Philadelphia, states he con- 
tinues to colled references to the literature of the Tan- 
nins with the expedation of further publication at no very 
distant date. 

Prof. Arthur M. Comey reports that his *' Didionary of 
Solubilities,'* vol. i., is nearly all in type, and should ap- 
pear early in the autumn. 

Dr. Alfred Tuckerman expeds to complete the MS. of 
his ** Index to the Mineral Waters of all Nations ** in a 
few months. 

Prof. F. W. Clarke is making progress with a new 
edition of the ** Re-calculation of the Atomic Weights." 

Dr. H. Carrington Bolton reports having done much 
work on the Supplement to his ** Bibliography of Che- 
mistry," the MS. now comprising about 6500 titles. 

Mr. C. LeRoy Parker, of the Columbian University, 
Washington, has undertaken an " Index to the Literature 
of Attempts to Decompose Nitrogen." 

Mr. George Estes Barton, of the same Institution, is at 
work on a ** Bibliography of Glycerol " ; and Mr. George 
Baden Pfeiffer, also of the Columbian University, is en- 
gaged on a " Bibliography of Picric Acid and the Nitro- 
phenols." 

At the request of the Smithsonian Institution Dr. H. 
Carrington Bolton has undertaken to edit a new edition 
of his *' Catalogue of Scientific and Technical Period- 
icals, 1665— 1882," published in X885 in the Smithsonian 
Miscellaneous Collections, The new edition will bring 



• Advance aheeU from Proctedings Amer, Assoc, Adw^Sdemee, 
vol. aliv., Gonunnnicated by ProCesMr U. Caniactoa Boltoa. 



CBB1I1C4L News* I 
Aug* so, iSgs. f 



Disinfection and Disinfectants. 



107 



down to date the old periodicals and iodade new ones 
ettablisbed since 1882. The work is well aoder way. 

Mr. W. D. Bigelow, of the Chemical Division of the 
U.S. Department of Agriculture, has completed the MS. 
of an '* Index to Methods for the DeteAion and BBtima- 
tion of Fusel Oil in Distilled Liquors.** The channel of 
publication has not been determtoed. 

In a communication to the chairmao. Prof. W. Percy 
Wilkinson, of Melbourne, sutes he is engaged on an 
" GSnological Biography,** to include works relation to the 
Yine, viticulture, wine-making, vine-diseases, and wine- 
nnidysis, published in Germany, France, England, 
America, Italy, Portugal, and Spain. He expeds tlM 
bibliography to number 2000 titles, and will give falf de- 
details as to date, size, editions, &c. It is to be published 
by the Royal Society of Vidoria. 

Monsieur Q. Fr. Jacques Boyer, Editor of the Rivus 
SasHtijiquij Paris, announces tho preparation of a 
** Bibliography of Physical and Chemical Science ** ; in- 
formation as to its scope and period is lacking. 

Those interested in the chemical applications of elec- 
tricity should note the following : — 
. **Elektrotechniaehe Bibliographie ; monatliche Rnnd- 
■chau iiber . . . der Blektrotechnik.** Von Georg Maas. 
Leipsig, X893. 

Also : *' Lelber*s Blektrotechnischer Katalog . • • von 
1884 bis 189I.** Leipsig, 1893. 8vo. 

The foll#wing special bibliography has recently ap- 
peared in Prance: — ** Bibliographie de la technologie 
chimique des fibres textiles. Propri^t^s, blanchiment, 
teinture, mati^res colorantes, impression, apprftts.** Par 
J. Garfon. Paris, 1893. S^* '^^is ^^^^ ^^ ^>^° 
honoured with a prixe by the Sociit6 Industrielle de 
Mulhouse. 

Although not pertaining to chemistry, we may briefly 
note the appearance of another special bibliography : — 
** Bibliographie der psycbo-physiologischen Litteratur des 
Jabres 1803.*' Hamburg, 1894. 8vo. Published in the 
Zniuhrififurd$4 Psychology und Pkysioiogis dtr SinmS' 

OTgOmH* 

Attempts to establish a comprehensive Index to Che- 
mical Literature ih the form of a periodical are not alto- 
gether successful, lacking the important element of 
permanence. Tbe ** Index " announced by Dr. Bechhold, 
of Frankfort-on«Main, noticed in our Twelfth Report, has 
not made its appearance ; the BiblioUca Polyteenica, by 
Sxcsepanski, ceased at the close of one year; the 
Umv€rsal ImUxt by Wien and Brockhaus, reached only 
nineteen numbm. Dr. J. Bpbraim advertises the fol- 
lowing, ** Index der gesammten chemischen Litteratur 
(Wissenchaft und Teoinologie), Berlin,** but no number 
has yet appeared. 

Committii : — 

H. Carrington Bolton, Chairman, 

F. W. Clarke, 

Albert R. Leeds, 

Alexis A. Julian, 

John W. Lamolby, 

Albert B. Frescott, 

Alfred Tuckerman. 
Aocotti X895. 



On Hezamethylenetetramine. — R. Cambier and A. 
Brochet. — Among the interesting properties of hexa- 
methyleneamine, the authors mention the formation with 
bromine and iodme of the addition-compounds C6HiaN4Xj 
and C6HUN4X4. The compounds with X4, being very 
unstable, lose in part their haloid element on mere expo- 
sure to air. Nitrous acid reads upon hexamethyleneamioe 
and forms in the first place dinitrosopentamethylene- 
teuamine, which is decomposed by acids and yields nitro* 
gen, ammonia, and formic aldehyd. Hexametbyleneamtne, 
if treated by acids, is easily split up by hydration into its 
Gomponenu.— B»//. Soc. Ckim, ds Paris, xiii.-xiv.a No. 4. 



NOTICES OF BOOKS. 



An IntroducHon to ths Study of Disinfgction and Distn* 
fictants. Together with an Account of the Chemical 
Substances used as Antiseptics and Preservatives. By 
Samuel Ridbal, D.Sc., F.I.C, F.C.S., ftc 8vo., pp. 
3x6. London : Charles Griffin and Co., Lim. 1895. 

The author of the work before us seu out with distin- 
guishing between disinfedants, antiseptics, and deodor- 
ants, classes of substances often confounded. Charcoal 
he classes not among disinfedants, but with the deodor- 
ants. The problem of disinfedion he shows is a struggle 
for existence between men and the pathogenic microbia, 
which, despite their minuteness, rank among our most 
formidable enemies. The methods of solving this 
problem are classed under the heads of excXusion, 
removal, and destrudion. 

Under the head of Mechanical Disinfedion the author 
enumerates a number of substances used as filter-beds, 
or in the treatment of fcecal matters and of impure 
waters. It is mentioned that light has a destrudive 
aAion on baderia, and even to some extent on their 
spores. Hence, as Dr. Percy Frankland rightly insists, 
every opportunity should be used for insolation in the 
construdion of water- works, and, we must add, of works 
for the treatment of sewage. 

The value of charcoal, animal and vegetable, is duly 
recognised. The former is credited with removing the 
ptomaines and a number of other hurtful organic com- 
pounds. The adion of certain residual carbons is very 
similar. The remark that ** a large number of processes 
have endeavoured to recover the phosphate (of sewage) 
by using the sludge as a fertiliser, but they have 
all met with little commercial success,** we must pro- 
nounce utterly mistaken. Soot is rightly said to have no 
great power, and coal-dust is with equal correAness 
proclaimed to be almost inert. The value of peat is fully 
recognised, but in the treatment of sewage care, wo 
must urge, should be taken to avoid pyritic samples, 
such as those of some distrids of Berks. 

Sterilised sand, according to Friiakel and Piefke, does 
not retain microbia. 

The Chamberland and Berkefeld filters — the latter made 
of infusorial earth, compressed and baked— are recom- 
mended for household use, but filters of stone and of 
asbestos are condemned, views which our experience 
enables us fully to endorse. 

The process of Scott Moncrieff has been tried and 
abandoned at Aylesbury. 

The process of disinfedion by means of hot air and 
steam is described at some length, with the addition of 
illustrations showing the plant employed. Incinerators, 
or destrudors for dust, ftc, are also noticed. 

The fourth chapter discusses chemical disinfedants. 
The opinions recorded concerning different agents and 
processes are far from agreeing. The Hermite process is 
judged unfavourably by Sir H. Roscoe and Lunt (p. 69), 
and by Dr. Kelly, the medical officer of health at Wor- 
thing, who incorporates the chemical and baderiological 
analyses of Drs. Dupr6 and Klein. Chamberland and 
Fembach allege that eau de Javelle (x : lao) and com- 
mercial hydrogen peroxide are more effedive than mercu- 
ric chloride against pathogenic microbia. 

The important caution is given that sodium chloride is 
not a disinfedant, and that brine sometimes acquires a 
high degree of toxicity. This is the more important as 
we have observed that stale brine is often kept and used 
for salting successive quantities of bacon, hams, fish, ftc. 

On the comparative value o( the halogens opinions 
differ. 

On chloroform, which has even been proposed for the 
treatment of sewage, Dr. Rideal remarks that its cost and 
its poisonous adion on animals render it of very limited 
application. 



io8 



Annual Report on Alkali Works. 



f Ohbmical Mbv9. 
1 Aapr. 30. 1895. 



The author recognttet that ** polluted water flowing 
over weirs and waterfalls is oxidised and becomes clear 
and brilliant,*' and again that " the self-puri6cation of 
rivers in this way is now accepted by most chemists, the 
natural aeration being aided by Infusoria and vegetation 
in removing most of the dead organic matter, and in re- 
ducing the number of micro-organisms present." These 
conclusions will meet with the approval of observant and 
unbiassed students of the sewage question. 

Sulphate of lime is rightly condemned as an ingredient 
in mixtures for the precipitation of sewage. It has the 
serious disadvantage— not mentioned here— of injuriously 
afifeding the health of the men employed in sewage- 
works. To find zinc salts still used in the disposal of 
•ewage is deplorable. 

The process Patent No. 11641 (1884), is travestied so 
as to give a very misleading impression of its nature. 
The summary of sewage precipitation processes given by 
Parkes and Corfield (p. 129) must be taken with a very 
large grain of salt. 

We regret that we cannot further examine this able and 
interesting work. Its weakest side is its criticism of pro- 
cesses for the treatment of sewage. 



Alkali, &»€., Works Rtgulation Act, 1881. Thirly-firs* 
Annual Rtport on Alkali, &»c,. Works by tht Chief 
Inspector. Proceedings during the Year 1894, presented 
to the Local Government Board and to the Secretary 
for Scotland. London : Her Majesty's Stationery 
Office. 
This Report is drawn up with great care and accuracy, 
and contains both alarming and reassuring features. 
The number of works in England, Ireland, and Wales, as 
now registered, is 1056, of which only xoa are alkali- 
works proper, whilst 954 fall within the schedules of other 
establishments recently included under the provisions of 
the Aa. Since 1893 there has been an increase of one 
alkali-works and nine other works. In Scotland there 
are za6 registered works, making a grand total of 1182. 

The number of processes of manufadure which fall 
within the provisions of the Aa is now 1520. The sepa- 
rate processes are : — Alkali, copper (wet process), sul- 
phuric acid, chemical manures, gas liquor, nitric acid, 
sulphate and muriate of ammonia, chlorine and bleaching- 
powder, sulphur recovery, salt, cement, alkali waste, 
barium and strontium, antimony sulphide, bisulphide of 
carbon, Venetian red, lead deposit, arsenic, nitrate and 
chloride of iron, muriatic acid, fibre separation, tar and 
zinc smelting. 

One most offensive process, of no national importance, 
has escaped attention,— to wit, ballast-burning, which, in 
most of the outskirts of London, fills the air with nause- 
ating fumes, and which ought to be totally suppressed in 
all urban distrids. 

The visits of inspedion to scheduled works are made 
about once monthly, unless there is apparent need for a 
closer investigation. In alkali w>Tks and sulphuric acid 
woiks definite limits are fixed as to the amount of acid 
fumes which may lawfully escape. In other cases the Ad 
merely requires that the best pradicable means for pre- 
venting the escape of noxious gases and vapours should 
be employed. 

The Report shows that the amount of hydrochloric acid 
in the chimney gases is less than one-half, the limit al- 
lowed by law ; whilst in case of sulphuric acid the escape 
is only about one-third of the legal margin. These fads 
are doubly satisfadory, as showing, on the one hand, that 
the standards fixed are reasonable, and, on the other hand, 
the watchful attention of the inspedors and the loyal 
compliance of the manufadurers. 

Two successful prosecutions have been conduded and 
fines inflided for evasions of the enadment that the in- 
spedor is to have full access to all apparatus used in 
carrying out the operations. 

It is satisfadory to learn that the Leblanc works hold J 



their own in virtue of the chloride of lime which they 
only are as yet able to produce. 

The effeds of the coal-strike of 1893 ^^^ b^*!' ^^'^ 
The salt decomposed in the Leblanc process was in 
the year 1892 519,593 tons, but has now fallen to 
434,298 tons. On the other hand, the salt consumed in 
the ammonia process has risen in the same time from 
304.897 tons to 361,603 tons. Thus the gain of the am- 
monia process is far from explaining or compensating the 
decline of the Leblanc process. The eledric alkali pro- 
cess, if the required energy has to be obtained from coal, 
is an amusing scientific version of the ** House that Jack 
built.** But the writer shows that where water power is 
cheap and abundant,— #. ^., Italy, Switzerland, South- 
eastern France, Norway, as well as the Dominion and 
the United Stalest,— both Leblanc and Solvay may find 
themselves in jeopardy. 

The ammonia lost by our wasteful system of coal- 
burning was estimated by Dr. Angus Smith at£'50,ooo,ooo. 
A yearly economy in this diredion, to the extent of 
£'2,000,000, has already been secured. 

In the treatment of tank-waste the Chance-Claus pro- 
cess works successfully. At Widnes, St. Helens, &c., 
raw waste is no longer deposited on the land — a subjed 
for public congratulation. But old beds of tank-waste, 
where they have been used for filling up. hollows and 
making embankments, still remain, and if they come in 
contad with acid leakage serious accidents may occur. 
A fatal case took place lately at Irvine, and is here re- 
corded. 

The manufadure of nitric acid is experiencing exten- 
sion. Mr. Manning Prentice, of Stowmarket, has made 
the process continuous, thus effeding at once economy 
and a suppression of possible nuisance. 

Coal-smoke is not a substance of which the inspedors 
under the Alkali Ad have to take official cognisance. 
But they are obliged to examine it, as its effeds are too 
often ascribed by the public to the emanations from che- 
mical works. About a million ton» of coal are burnt 
yearly at Widnes. This coal contains about i| per cent of 
sulphur, and thus generates 30,000 tons of sulphurous 
acid, which is diffused over the country. The effeds of a 
sooty atmosphere and ol sulphurous acid are rightly 
considered by Mr. Fletcher, the chief inspedor, as 
taking no small share in the injury to vegetation. He 
thinks that the ** open fire is incorrigible,*' and he fears 
that the love of an Englishman for the cheerful blazing 
fire will stand in the way of any reform. He men- 
tions, however, the case of " one house, inhabited by 
a large family, where recently, during a week of frosty 
weather, twenty-one open fires and five oil or gas stoves 
were kept burning." He thinks that one of the twenty- 
one fires, if burnt in a properly construded stove, would 
have heated the whole house better than the twenty-one 
in open grates. 

In a passage quoted from Die Chemische Industrie, on 
the health of the workmen employed by the Griesheim 
Chemical Co., it is declared, on the authority of Dr. C. 
Wolff, for ten years medical officer to the works, that— 
*' As in former years, artisans such as carpenters, coopers, 
smiths, &c., show a higher percentage of sickness than 
the process men,'* t. e , those employed in the manufac- 
ture of sulphuric acid, hydrochloric acid, nitric acid, 
soda-ash, caustic soda, nitrobenzene, picric acid, cbrom- 
ates, &c. 

We have every reason to conclude that the present 
Chief Inspedor, Mr. A. £. Fletcher, and his colleagues 
are proceeding on the lines laid down by his distinguished 
predecessor, Dr. R. Angus Smith. 



Report of the Dairy Commissioner of the Stat* of New 

Jersey, For the Year 1894. New Jersey : Trenton. 
This Report will be of the greatest value t o un itary 
chemists. We find that in the United States the liasility 
of milk to pollution and its danger to public h.al^^art 



A 



Crbhical Kiws, I 
Ang. so. xb95. f 



Chemical Notices from Foreign Sources. 



109 



fully recognised by the Courts, by men of Science, and 
even by the general public. We fear that in this last 
respeft we, in this country, do not hold the first rank. 
Strid legislation and analytical skill, chemical and micro- 
biological, fall short of their aim unless supported by 
enlightened public opinion* 

But in America very much remains to be done. We 
learn that ** the standard of Z2 per cent solids is so low 
that most whole milk can be watered — and much is— with 

f^reat precision, so as just to escape the penalties of the 
aw.** In Hudson and Essex counties nearly 2500 stables 
were found by the inspedors, in most of which the cattle 
Were kept in a crowded and unhealthy condition, and in 
which the principal food was wet and soured brewers* 
grains. The Commissioner proposes raising the standard 
to 12*5 per cent total solids, with a minimum of 3*5 per 
cent of fat. 

The importance of cleanliness in cow-houses and 
dairies is now beginning to be appreciated. In some 
establishments the cattle are groomed previous to milk- 
ing ; their udders are washed ; the milkman is required 
to exchange his ordinary working clothes for a clean- 
washed smock, and to wash his hands and remove the 
ofifensive dirt from his finger-nails (which is otherwise — 
horribilt dictu — washed out by the warm milk and 
carried into the pail). But even this improvement falls 
short of what is needed. It is truly remarked that when 
atraw becomes damp and filth-stained, and then raised to 
the temperature of blood-heat by the cattle lying upon it, 
such straw becomes a most prolific breeding-ground for 
baderia. '* Every movement of the cow and the milkman 
4'aises up a cloud uf baderial dust from the bedding, and 
until a substitute is provided this dust will continue.*' 

It may be asked whether peat. litter might not be found 
in this resped preferable to straw? It is proposed to 
dispense with bedding altogether, and let the cows lie on 
a clean inclined plank floor, made waterproof and with 
the seams caulked, all excreta being forthwith removed. 

Ao interesting fad here mentioned is that, with a nearly 
identical food, the best cow produced a| times more milk 
and 3 times more butter than the poorest cow (referring 
to certain experiments performed at Kildebrdnde, in 
Denmark). 

From fads ascertained we learn the importance of re- 
frigerating milk before being conveyed to consumers. 

Mention is made of pasteurised milk, of sterilisation, 
and of a ** certified milk ** the preparation of which has 
been described in a former repon, and in which the num- 
ber of baderia per c.c. is only a few hundreds instead of 
from 10,000 to 60,000 baderia. The alleged sterilisation 
is sometimes illusive. 

None of the brands of condensed milk here described 
are known in Britain. 



CHEMICAL 



The Pharmaceutical youmal of Australasia, Vol. VIII., 

No. 5. 
Thb interesting fad in this issue is the opening of 
chemical works by Messrs. Elliott, at Brisbane. The 
immediate objed of the firm is the produdion of sul- 
phuric acid, the freight of which from Britain may be 
considered prohibitory. No information is, however, given 
as to the supply of pyrites, its quantity and quality. 

Ulterior objeds of the firm are the manufadure of 
potassium cyanide, the nitrogenous matter being the refuse 
from the meat works ; the produdion of compressed car- 
bonic acid, and that of superphosphate. For all these 
produds there cannot (ail to be a large opening in 
Australia. 

The Atomic Weights of Nickel^ and Cobalt.— 
Clemens Winkler. — The author finds the atomic weight 
of nickel, as calculated from the mean result of his ex- 
periments, 587433, and that of cobalt 59*3507» These 
atomic weigntn are referred to H«bx and 10x26*53. — 
ZtU, Anorg, Chemn. 



NOTICES FROM 
SOURCES. 



FOREIGN 



NoTB.— All degrees of temperature are Centigrade anless otherwise 
expretted. 

Comptes Rmdus Hebdomadaires dts Seances, de VAcademU 
des Sciences, Vol. cxxi.. No. 6, August 5, 1895. 
Illumination by Luminescence.— A. Witz.— (See 
p. X04). 

Bulletin de la SocUU Chimiaue de Paris, 
Series 3, Vols, xiii.-xiv., No. 4, 1895. 
Nickel and Cobalt Sulphides.— A. ViUiers.— Already 
noticed. 

Qualitative Separation of Nickel and Cobalt. — A. 

ViUiers. — Already noticed. 

Protomorphic States of Zinc and Manganese Sul- 
phides.— A. ViUiers. — Already noticed. 

Researches on the Basic Nitrates.— M. Athanesco. 
— The author finds that the process of which he has 
spoken in a former paper is not novel, but had been pre- 
viously employed by other chemists. His objeds have, 
however, been dififerent. He seeks to show that the basic 
compounds contain hydroxyls attached to the metals 
which they completely saturate, and that very often in the 
conditions of the formation of the basic salts the pluri- 
valence of the atoms takes always a preponderating part 
in the diredion that, in place of obtaining compounds 
derived frum anhydrides of the first, second, or third 
degree, we may obtain them corresponding to the highest 
degree of hydration of the non-metal. He turns his 
special attention to the lead nitrates. 

On the 2-Ethy]-4-Methylpentanoic OAylic Acid. — 
Ph. A. Guye and J. Jeanprfttre.- Not adapted for useful 
abstradion. 

A<5tive Amylacetic Acid and some of its Deriva- 
tives.— MdUe. I. Welt.— The chief result of these experi- 
ments relates to the ethers of amylacetic acid. If we cal- 
culate the values of the produd of asymmetry of the 
methylic and ethylic ethers, we find decreasing numbers ; 
it is the same with the rotatory powers. We cannoti 
then, meet with in this series an ether with a maximum 
rotatory power, as the first term is already on the 
descending branch of the curve. 

Contribution to the Study of the Tartaric Ethers. 
—Ph. A. Guye and J. Fayollot.— Already noticed. 

New Process of Preparing a-Naphtholsulphonic 
Acid, C10H6.OH.H.SO3 x-4.— Fred. Reverdin.— None of 
the procedures hitherto employed are founded upon the 
dired sulphonation of a-naphthol. The author and his 
colleague, De la Harpe, have found the carbonic ether of 
a-naphthol an excellent primary material for the prepara- 
tion of naphtholsulphonic acid 1-4. In the industrial pro- 
dudion, carbon oxychloride is passed at the common tem- 
perature into a solution of — 

a-Naphthol.. •• 60 kilos. 
Soda-lye .. .. 60 „ 
Water xooo „ 

Sulphonated Colouring Matters derived from Tri- 
phenylmeihane. — Maurice Prud*homme. — The author*8 
experiments establish the complete parallelism between 
the series of rosaniline and its derivatives and the corre- 
sponding series of sulphonated rosaniline, and support the 
constitutional formulae which Rosenstiehl has proposed 
for these two classes of substances. All the properties 
of magenta which I have pointed out re*occurin the bases 
of malachite green and of hexamethylated violet. All 
those of acid magenta re-occur in acid green and magenta 
and in Nicholson blue. The alkaline salts of sulphonsted, 
uianiido, and triamido iriphenylcarbinols are colourless. 



no 



Chemical Notices from Foreign Sources. 



f Crbmical Nswt, 
I Aug. 30. 189J, 



These substances may be considered as hydrated organic 
bases. The salts of these bases, where the hydroxy] 
may be replaced by an acid radicle, are coloured. Acid | 
magenta is, or may be, according to proportions of hy« ' 
drocbloric acid added to the colourless alkaline salt, a ! 
mixture of HO— C^CCeHs.SOaNa.NHa)) (colourless) and 
of coloured CI— C=(C6H3.S03NaNH2)3, or even of this 
latter body and CI— C=(C6H3.S03H.N 113)3 (coloured). 

Insufficieocy of Kjeldahrs Method for DetermiDing 
Nitrogen in the Chloroplatinates.— M. Del6pine. — 
Already noticed. 

No, 7, X895. 

This issue contains a long notice of the life and re- 
searches of E. A. Rtgout, a distinguished chemist who 
died in August last at the age of seventy-five. During the 
year 1S71 he had remained alone in charge of the Ecole 
des Mines, and at no small risk to his life he contrived to 
save this establishment from destrudlion. 

On the Cryohydrates. — A. Ponsot. — After a careful 
and prolonged examination the author concludes that the 
cryohydrates of Guthrie do not exist, but are merely mix- 
tures of pure ice and of a solid salt, hydrated or 
anhydrous. 

Influence of Temperature and of the Ambient 
Medium on the Transformation of Amorphous Zinc 
Sulphide.— A. Villiers. 

Method of Determining the Crystallisation of Pre- 
cipitates, Zinc and Manganese Sulphides, Man- 
ganese Hydroxide. — A. Villiers.— Already noticed. 

Oxides and Sulphides having an Acid and a Basic 
Pun(5tion. Zinc Sulphide.— A. Villiers. — The study U 
the properties 0/ oxides and sulphides has led us to think 
that the acid and alkaline fun^ions which may be fulfilled 
by indififerent oxides and by some sulphides do not 
belong, at least in a number of cases, to one and the 
same substance, but to two varieties, distind in their 
chemical and physical properties. In the case of precipi- 
tated zinc sulphide, we may distinAly recognise the exist- 
ence of two varieties. 

Analytical Characters of a Mixture of Barium, 
Strontium, and Calcium Salts.— H. Baubigny. 

Non-Existence of the Mixed Anhydrides.— L. 
Rousset. — When proceeding on the usual method the 
author has obtained merely a mixture of two anhydrides. 
This was found to be the case with the alleged acetyl- 
butyric, acetyl-valerianic, and acetyl -benzoic acids. 

Adiion of the Asymmetric Ketonic Compounds 
upon the Primary Aromatic Amines. — Louis Simon. 
— In the adion of pyruvic acid upon a primary aromatic 
amine, there are formed simultaneously several com- 
pounds, but they are neither stereoisomers nor even 
strudtural isomers. 

A<5tion of the Chlorides of Acida upon Hezachloro- 
phenol-a in presence of Aluminium Chloride. For- 
mation ot Ethers of Pentachlorophenol. — E.Barral. 

Adion of Aluminium Chloride on a*Hexachloro- 
phenol.— E. Barral.— These two memoirs are not adapted 
for useful abstraAion. 

On Piperonylidene-acetone. — L. Rousset. — If 20 
grros. of pure piperonal, regenerated from its bisulphite, 
are dissolved in 50 grms. dimethylketone, and if to this 
solution there are added 500 grms. water and 50 grms. 
soda at 10 per cent, on stirring the mixture heats, and 
there is produced a light yellow precipitate. This pre- 
cipitate, if re-crystallised from alcohol, forms the compound 
in question. 

Compound of Hexamethyleneamine with Bismuth 
Iodide. — M. Del^pine. — This compound conuins— Bis- 
muth, 16*83 ; iodine, 58*24 ; nitrogen, 7*35 ; and hwaier, 
5*82 per cent. 

On Hexamethyleneamine. (Further Continuation). 
— M. Del^pine. — An account of the salts of the ammo- 



niums:— The iodamylate, the adion of adds, and th« 
formation of primary amines. 

On Hexamethyleneamine. (A ContinnaCton).— M. 
Del^pine.— The author describes here the solnblUties, the 
hydrate, bromide, sulphate, and phosphate. 

Oxidising Power of Laccate.— G. Bertrand.— The 
author has opined from the latex of the lac tree of 
Tonkin a newloluble ferment, which he names i^rn tff. 
This new ferment has the specific cbarader of setting up 
the direa oxidation of the substances upon which it ads. 
It is thus distinguished from all the ferments previously 
known which occasion merely hydration and splitting np. 
The results cannot be ascribed to the adion of micro- 
organisms, as the media in which the experiments were 
conduced were antiseptic. 

Watering Milk. Its Detedion by an Examination 
of the Whey.— H. Lescoeur.— Every sample of milk 
which gives a serum of specific gravity below 1*027, '^^ 
the solid matter of which does not amount to 67 grms. per 
litre, may be declared as ** watered.'* 



DEPARTMENT OP SCIENCE AND ART. 
ROYAL COLLEGE OP SCIENCE, DUBLIN. 
O equired a Demonstrator of Chemistry and 

, ^ , AMtying^For particuUn apply to SicasTAar. Royal Col- 
lege of Science, Dublin. 



yUST PUBLISHED, Large Crown Svo., with Diagrams 
and Working Drawings, 7s. 6rf. cloth. 

THE CYANIDE PROCESS 

FOR THB 

EXTRACTION OF GOLD, 

And its PraAical Application on the Witwatersrand 
Gold Fields in South Africa. 

By M. EISSLER, Mining Enoinebr, 
Aulbor of ** The Metallurgy of Gold," ftc. 

** This book ia jutt what was needed to acquaint miniog mro with 
the aaual working of a proceaa which it not only the most popular, 
but if, aa a general rule, the roost tncceaaful for the extraaioo of cokl 
from Uilings."— iftiiMig Journal. 

LOMDOM : 

CROSBY LOCKWOOD & SON, 7. SUtionets* HaU Coart, B.C. 



AC£/XON£ — Answering all reqairementa. 

-A-OIX) -A.OETIC— Purest and aweet. 

IBOIR-A-CIO— Cryat. and powder. 

CXTErlC—Cryat. made in earthenware. 

-^ G-A-XiIjIO— From beat Chineae galla, pore. 

S.A.IjIOirijIO— By Kolbe'a proceaa. 

T.A.IiT:KriO— For Pharmacy and the Arta. 

LIQUID CHLORINE 

(Compressed ia steel cylinders). 

FORMALIN (407^ CHaO)— Antiseptic and Preservative. 

POTASS. PBRMANOANATB-Cryst., large and small, 

SULPHOCYANIDB OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICAtS FOR ANALYSIS AND THB ARTS. 

Wholesale Agents— 

A. & M. ZIMMERMANN, 

6 « 7, CR0S8 LANE LONDON, E.G. 



CvtancALNtwt,! 



Address to Students. 



Ill 



THE CHEMICAL NEWS. 

Vol. LXXII., No. 1867. 
(STUDENTS' NUMBER). 



ADDRESS TO STUDENTS. 

Perhaps a majority of the students to whom we 
venture to address our annual remarks look forward 
to the utilisation of the knowledge they are 
acquiring in some art or manufadture with which 
they hope to be specially conne<5ted ; but there are 
others— too many we fear— who regard chemistry 
as the basis of an independent profession. Such 
men, in Britain, labour under the inconvenience of 
having as a body no recognised and distinctive 
name. In France they would be known as 
•• Chemistes," and in Germany as ♦* Chemikcr," but 
the English equivalent of these terms has been in 
our country appropriated by the profession who are 
more suitably known in France as " Pharmaciens " 
and in Germany as " Apotheker," but who, with us, 
thow no disposition to abandon the name of 
chemists. Nay, if " Tom Brown's " exposition of 
the law be correct, even such qualified designations 
aa " analytical chemist " are the exclusive prpijerty 
of the compounders and dispensers of medicines. 
Some suggest the name " Analysts," which, how- 
ever, connotes only a portion of the fundtions of the 

Profession whose cause we are pleading. Professor 
luxley, were he still living, might perchance have 
invented for us an unobje<5tionable name, which for 
the present must be allowed to stand over as a 
desideratum. . 

Concerning the relative rank of the profession 
our esteemed contemporary the Chemiker Zeitung 
is much exercised. It contends that if all chemists 
before being entitled to exercise their profession 
were obliged to pass a '* Staat's examen,'* after their 
University career, they would no longer be regarded 
aa inferior (!) to engineers and law>*ers. What effea 
such an examination might have upon German 
public opinion we cannot presume to decide. But 
in the opinion of the world German chemists rank 
incomparably higher than any lawyers or engineers. 
No names among the latter classes carry with them 
the spell which adheres to the names of Liebig, 
Wcebler, Bunsen, or Hofmann. We are painfully 
conscious that in Britain, as no doubt also in 
Germany, the emoluments of the lawyer and of the 
engineer exceed those of the chemist. With us 
neither the engineer nor the chemist is a State- 
official. The latter is indeed relatively poor, since 
when he gives advice, whether to a private firm or 
to a public body, he is not paid by a percentage on 
the outlay which his schemes necessitate. Could 
he claim a percentage on the economy which he 
renders possible, he would be a more prosperous 
man than he is at present. Moreover, he is beset 
with difficulties to which, eg., the engineer and the 
lawyer are strangers. He is, if we may use the 
expression, trespassed upon in all possible dire<5tions. 
As an instance, the difference between pure water 
and contaminated water is purely chemical and 
micro-biological. Only the chemist and the micro- 
biologist can appreciate such difierencci can know 



how to encounter it, and can judge if and in how 
tar the methods used are successful. Yet, when the 
treatment of the sewage of London was under dis- 
cussion, it was actually suggested that the engineer 
who had designed the Forth bridge — a matter purely 
mechanical — should be consulted ! Why, had he 
even succeeded in building a railway across the 
Straits of Dover, that fadt would have been no evi- 
dence of his power of purifying a single gallon of 
sewage. It is a strange thing that the Rivera' 
Pollution Commission included only one chemist 
to two engineers, and no microscopist or physician. 
In a very like manner, when question arises before 
any municipal body concerning the treatment of 
polluted waters, it is forthwith proposed to consult 
some eminent enpnur. 

But the chemist fares almost as badly at the 
hands of the legislature and its officials as does the 
experimental physiologist. The ukase ordering the 
addition of coal-naphtha to methylated spirits still 
exists, and causes a great hindrance to scientific 
research. The addition of a mere trace of Dippel's 
animal oil — as it is sanctioned by the German law— 
would have rendered the spirit more thoroughly un* 
drinkable, without inflidting such annoyance on tha 
chemical manufacturer and the scientist engaged in 
research. It further appears that a chemist is, 
strictly speaking, liable to a tax on every retort, &c., 
in his laboratory, of what material soever, and 
however incapable of being used for the illicit dis- 
tillation of spirits. 

Further, there is a chronic agitation kept up by 
some medical men( especially medical officers of 
health) and by a few pharmacists, to encumber the 
sale of the ordinary mineral acids with red-tape pre- 
cautions. Any such ena<5tment cannot have other 
than an unfavourable adtion upon chemical research. 
" Free research *' should be the watchword of every 
man of Science, and it is in the long run essential 
to the welfare of the community. 



UNIVERSITIES_AND COLLEGES. 

UNIVERSITY OF LONDON. 
Candidatxs for any Degree in this University must have 
passed the MatricuUtion Examinatioo. No exemption 
from this mle is allowed 00 account of Degrees obtained 
or Examioations passed at any other University. This 
and all other Examinations of the University, together 
with the Prises, Exhibitions, Scholarships, and Medals 
depending upon them, are open to Women upon exaAly 
the same conditioos as to Men. 

There are two Examinations for Matricolatlon in each 
jrear ; one commencing on the second Monday in January, 
and the other on the second Monday in June. 

The Examination is conduded by means of Printed 
Papers; bat the Examiners are not precluded from 
putting, for the purpose of ascertaining the competence of 
the candidates to pass, viva voc# questions to any candidate 
in the iubjeds in which they are appointed to examine. 
These Examinationi may be held not only at the Uni- 
versity of London, but also, under special arrangement, 
in other parts of theUnited Kingdom, or in the Colonies. 

Every candidate for the Matriculation Examination must, 
not leii than five weeks before the commencement of the 
Examination, apply to the Registrar for a Form of Entry, 
which mutt be retamed not less than four weeks before 
the commencement of the Examination, accompanied by 
a Certificate showing that the candidate has completed 
hts sixteenth year, and by bis Fee (or the Examination. 



112 



Schools oj Chemistry. 



ICMBMIGALNlWt, 
Sept. 6. 1894. 



As no candidate can be admitted after the List is closed, 
any candidate who may not have received a Form of 
Entry within a week after applying for it must communi- 
cate immediately with the Registrar, stating the exadt 
date of his application and the place where it was posted. 
Every candidate entering for the Matriculaiion Exami- 
nation for the first time mnst pay a Fee of £2 to 
the Registrar. If a candidate withdraws his name, or 
fails to present himself at the Examination, or fails to 
pass it, the Fee shall not be returned to him, but he shall 
be allowed to enter for any subsequent Matriculation 
Examination upon payment, at eveiy such entry, of an 
additional Fee of £1, provided that he comply with 
the Regulations in the preceding paragraph. 

Candidates are not approved by the Examiners unless 
they have shown a competent knowledge in each of the 
following subjeds : — Latin. Any one of the following 
Languages : — Greek, French, German, Sanskrit, or 
Arabic. The Ehglish Language, and English History, 
with the Geography relating thereto. Mathematics. 
Mechanics. One of the following branches of Science : — 
Chemistry, Heat and Light, Magnetism and Ele^ricity, 
Botany. 

The Examination in Chemistry is — Chemistry of the 
Non-metallic Elements ; including their compounds, 
their chief physical and chemical charaders, their pre- 
paration, and their charadleristic tests. 

A Pass Certificate, signed by the Registrar, will be 
delivered to each successful candidate after the Report of 
the Examiners has been approved by the Senate. 

If in the opinion of the Examiners any candidates in 
the Honours Division of not more than twenty years of 
age at the commencement of the Examination possess 
sufficient merit, the first six among such candidates will 
leceive an Exhibition of thirty pounds per annum for 
the next two years ; the second among such candidates 
will receive an Exhibition of twenty pounds per annum for 
the next two years ; and the third will receive an Exhibi- 
tion of fifteen pounds per annum for the next two years ; 
such exhibitions are payable in quarterly instalments 
provided that on receiving each instalment the Exhibi- 
tioner declares his intention of presenting himself either 
at the two Examinations for B. A., or at the two Examina- 
tions for B.Sc, or at the Intermediate Examination in 
Laws, or at the Preliminary Scientific M.B. Examina- 
tion, and Intermediate Examination in Medicine, within 
three academical years from the time of his passing 
the Matriculation Examination. 

Under the same circumstances, the fourth among such 
Candidates will receive a prize to the value of ten 
pounds in books, philosophical instruments, or money ; and 
the fifth and sixth will each receive a prize to the value of 
five pounds in books, philosophical instruments, or money. 
Any candidate who may obtain a place in the Honours 
Division at the Matriculation Examination in January is 
admissible to the Intermediate Examination either in 
Arts or in Science in the following July. 

Intirmbdiate Examination in Scibncb. 
_ The Intermediate Examination in Science will com- 
mence on the third Monday in July. 

No candidate (with the exception of such as have 
obtained Honours at the Matriculation Examination in 
the preceding January^ is admitted to this Examination 
within one academical year of the time of his passing the 
Matriculation Examination. 
The Fee for this Examination is £$. 

Examination for Honours, 

Candidates for Honours in Chemistry will be examined 
in Inorganic Chemistry, treated more fully than in the 
Pass Examination. In addition, they will be examined 
pra^ically in Simple Qualitative Analysis. This Ex- 
mination will consist of six hours' examination* by 
two printed papers and of six hours* pradtical work. 

In the Examination for Honours, the Candidate, not 



being more than 22 years of age at the commencement of 
the Pass Examination, who most distinguishes himself 
will receive an Exhibition of £^0 per annum for the next 
two years. 

B.Sc. Examination. 

The B.Sc. Examination will be held on the third Monday 
in Odober. 

Candidates for this Examination are required to have 
passed the Intermediate Examination in Science at least 
one academical year previously. 

The Fee for this Examination is £5, 

Examination for Honours, 
The examination for Honours in Chemistry will take 

f>lace on Monday, Tuesday, and Wednesday in the week 
bllowing the Examination for Honours in Mathematics ; 
on Monday by printed papers (chiefly on Organic Che- 
mistry), and on Tuesday and Wednesday by pradical 
examination in Qualitative and Quantitative Analysis. 

The candidate, being not more than 23 years of ape, 
who most distinguishes himself in Chemistrv, will receive 
£50 per annum for the next two years, with the style of 
University Scholar. 

Doctor op Scibncb. 

'X*he examination for the Degree of Dodor of Science 
takes place annually within the first twenty-one days of 
June. 

No candidate is admitted to the examination for the 
Degree of D.Sc. until after the expiration of two Aca- 
demical Years from the time of his obtaining the Degree 
of B.Sc. in this University. 

Every candidate for tliis Degree niuf^t state in writing 
the special subjed within the purview of the Faculty of 
Science, asset out in the Programme of the B.Sc. Ex- 
amination, upon a knowledge of which he rests his 
qualification for the DoAorate ; and with this statement 
be shall transmit an original Dissertation or Thesis (at 
least six copies), printed, type- written, or published 
in his own name, treating scientifically some special 
portion of the subjed so stated, embodying the 
result of independent research, or showing evidence 
of his own work, whether conduced independently or 
under advice, and whether based on the discovery of new 
fads observed by himself, or of new relations of {2t€L% 
observed by others, or, generally, tending to the advance- 
ment of Science. Every candidate may further specify any 
printed contribution or contributions to the advancement 
of Science which he has at any time previously published. 
If the Dissertation or Thesis be approved by the 
Examiners, the candidate shall be required to present 
himself at the University upon such day or days within 
the first twenty-one days of June as may be notified to 
him, and shall, at the discretion of the Examiners, be 
further tested, either orally or pradically, or by printed 
questions or by all of these methods, with reference both 
to the special subjeA selected by him and to the Thesis. 

Preliminary Scientific (M.B.) Examination.* 
This Examination takes place twice in each year, — 
once, for Pass and Honours, commencing on the third 
Monday in July ; and once for Pass Candidates only, com- 
mencing on the third Monday in January. 

No candidate shall be admitted to this Examination 
unless he shall have passed the Matriculation Examina- 
tion. Not less than five weeks before the commencement 
of the Examination be must apply to the Registrar for a 
Form of Entry, which must be returned not less than four 
weeks before the Examination, accompanied with the 
candidate's fee. 
The Fee for this examination is Five Pounds. 



Candidates who pass in all the sobjt As of the Prelimiiutv Scicn- 
f M.B.) £xaminatioo, and also pass at the same time in tf 
and Mixed Mathtmatics of the Intermediate Examination in Science, 



Pore 



or who have previously passed the Intermediate Exaraioatioa m 
Arts, are admissible to the B Sc Examination. 



CbbmicalNew!.! 

Sept. 6, 1894* f 



Schools of Chemistry. 



"3 



UNIVERSITY OF OXFORD. 
W^nfl4U Profassar of Chemistry, ^"W. Odling, M.A., 

Every Stadent mast reside in one or other of the Col- 
leges or Halls, or in licensed lodgings, for a period of thrc« 
jrears, passing at least two examinations in Arts, and one 
in either Mathematics, Natural Science, Law, Modem 
History, or Theology, when, if he obtain a first, second, 
or third class, he can take his B.A. Degree ; if he do not 

£un such honour he has to pass a third examination in 
iUrU HwHonioribus, 

The fee for students working in the Laboratory for 
three days in the week during the Term is £'^ ; for 
students working every day, £$. 

Scholarships of about the value Oi £'j$ are obtainable 
at Christ Church, Magdalen, and other colleges, by com- 
petitive examination in Natural Science. 

More detailed information may be obtained from the 
University Calendar; the Examination Statutes, 1894; 
the Student's Handbook to the University ; and from the 
professors. 

UNIVERSITY OF CAMBRIDGE. 

Professor of Chemistry,— Q. D. Liveing, M.A., F.R.S. 

yacksonian Professor of Natural and Experimental Phi' 
losophy.—]. Dewar, M.A., F.R.S. 

The Student must enter at one of the Colleges or 
Hostels, or as a Non-collegiate Student, and keep terms 
for three years by residence in the University. He must 
pass the previous examination in Classics and Mathe- 
matics, which may be done in the first or third term of 
residence, or, through the Oxford and Cambridge Schools 
Examination Board, or through the Senior Local Exami- 
nations, before commencing residence. He may then 
proceed to take a Degree in Arts, either continuing 
mathematical and cliissical study, and passing the or- 
dinary examinations for B.A., or going out in one of the 
Honour Triposes. 

The scholarshiDt, ranging in value from £20 to £100 
a year, are chiefly given for mathematical and classical 

Sroficiency. Scholarships, or Exhibitions, are given for 
Fatural Science in King's, Trinity, St. John's, St. Peter's, 
Clare, Trinity Hall, Queen's, Jesus, Christ's, Sidney, 
Pembroke, Caius, and Downing Colleges ; the examina- 
tions being in December, at Easter, and in June and 
Odober. 

The Chemical Laboratory of the University is open 
daily for the use of the Students. The Demonstrators 
attend daily to give instrudions. A list of the ledures is 
published annually, in June, in a special number of the 
Cambridgt University Reporter^ which may be had from 
the Cambridge Warehouse, in Paternoster Row, or through 
any bookseller. 

Non-collegiate Students are allowed to attend certain 
of the College Ledures and all the Professors' Ledures, 
and have the same University status and privileges as the 
other Students. Full particulars may be obtained by 
forwarding a stamped direded envelope to the Assistant 
Registrar, Cambridge, or from the Cambridge University 
CtSendar, 

UNIVERSITY OF DUBLIN. 
Trinity Colleob. 

Professor of Chemistry,-^}, Emerson Reynolds, D.Sc, 
M.D., F.R.S. 

Assistant Lecturer.— Emil A. Werner, F.C.S., F.I.C. 

Demonstrator.— Wiilisim Early, F.I.C. 

The general Laboratories include working accom- 
modation for lao Students, and the Quantitative and 
Research Laboratories for about ^o Students. The 
Laboratories will open on the xst of Odober. Ledures 
will commence about November xst. 

The Laboratories and the Ledures of the Professor of 
Chemistry can now be attended by Students who do not 
desire to reside in the University or proceed to its Degrees. 

The full Course of General and Analytical Chemistry 



occupies three years, but a Student is free in his third year 
to devote most of his time to a special department of 
Pure or Technical Chemistry. Students can enter for 
any portion of the Course. The following Ledures are 
delivered : — 

X. Inorganic Chemistry and Chemical Philosophy. -^ 
Elementary, first year ; advanced, second year. 

2. Organic Chemistry, — General, second year ; ad- 

vanced, third 3rear. 

3. Metallurgy. — A Course for Engineering and Tech- 

nical Students. 

The Laboratories are open every day from 10 to 5 
o*clock (except Saturdays, when they close at x o*clock). 

The Summer Course of Practical Chemistry for Medical 
Students begins during the first week in April and termi- 
nates with the first week in July. 

The University of Dublin grants the Degree of Dodor 
of Science to graduates of Master's standing whose in* 
dependent researches in any branch of Science are of 
sufficient merit. 

KING'S COLLEGE. 

(Division op Bnoinbbring and Applibd Scibncb). 

Professor of Chemistry.— J. M. Thomson, F.R.S.B., 
F.C.S. 

Demonstrator of Practical Chemistry. — Herbert Jackson, 

Assistant Demonstrators.—^. H. Kirkaldy and W. H. 
Sodeau. 

Students of the First Year are admitted to the Course 
of Theoretical and Applied Chemistry. The Course 
commences with a View of the Forces which concur to 
the produdion of Chemical Phenomena, after which the 
laws of Chemical Attradion are discussed, and the Non- 
metallic Elements and their principal compounds are 
described. The Metals and their principal compounds 
are next examined, care being taken to point out the 
applications of the Science to the Arts; and the pro- 
cesses of the dififerent Manufadures and of Domestic 
Economy are explained and illustrated. Examinations of 
the Class, both vivd voce and by written papers, are held 
at intervals during the course at the usual Ledure hour. 

Second Year, — Students attend in the Laboratory twice 
a week, and they go through a course of Manipulation in 
the most important operations of Chemistry, including; the 
first steps of Analysis. Any Student of this Division 
may be admitted to this Class at any period of his study 
on payment of an extra fee. 

Experimental and Analytical Chemistty in the Labora- 
tory, — The objed of this Class is to afford to Students 
who are desirous of acquiring a knowledge of analvsis, or 
of prosecuting original research, an opportunity of doing 
so under the superintendence of the Professor and De- 
monstrator ; Students may enter, upon payment of extra 
fees, at any time except during the vacation, and for a 
period of one, three, six, or nine months, as may best suit 
their convenience. The laboratory hours are from ten till 
four daily, except Saturday, on which day the hours are 
from ten till one. 

In addition to the Laboratoiy Fee, each Student defrays 
the expenses of his own experiments. The amount oi 
this expense, which is comparatively trifling, is entirely 
under his own control. 

Special hours and fees are arranged for the convenience 
of such Third Year Students as wish to study Analytical 
Chemistry. 

Pees. — Chemistry per term, £3 3s. od. ; per ann., 
£8 88. od. ; Pradical Chemistry per term, £^^ 4s. od. ; per 
ann., ;^io los. od. ; Experimental and Analytical Chemistry 
— Daily attendance : One month, £4 4s. ; Three months, 
;(xo los. ; Six months, £x8 iSs. ; Nine months, £26 5s. 
Three days a week : One month, £2 las. fid. ; Three 
mos., £t 68. ; Six mos., ;f 11 xis. ; Nine mos., £15 158. 

Rules as to Admission of Students. 
I. The Academical Year consists of Three terms : 
Michaelmas Term, from beginoiog of Odober to the week 



"4 

before Christmas ; Lent Term, from the middle of January 
to the week before Easter; Easter Term, from Easter to 
the beginning of July. 

II. The days fixed for the Admission of New Students: 
in the Academical Year 1895-96, are Tuesday, Odober i, 
Wednesday, January 15, and Wednesday, April 2a. 
Metallurgy. 

Professor. —K. K. Huntington, F.I.C.. F.C.S., &c. 

The following suWeds are treated of in the Ledures : 
The Seledion and Economic Preparation of Fuel and of 
Refraaory Materials ; the methods by which metals are 
obtained from their ores, and the means by which they are 
rendered suitable for the various requirements of the Arts. 

Particular attention is paid to the study of the Nature 
and Properties of Metals and Alloys available for Con- 
Btrudive Purposes. 

In the Metallurgical Laboratory, which is always open 
during College hours, the relation l>etween the Chemical 
Composition of Metals and their Mechanical Properties 
may be studied by the aid of Testing Machinery. 
Photography. 

Licturer.—VtoU J. M. Thomson, F.R.S.E., F.C.S. 
. Arrangements are made for a complete Course of 
Instrudion in Photography to the students of the third 
year. A glass house has been ereded, and in connection 
with it a Laboratory for the preparation of Photographic 
Chemicals. Students entering to this department will be 
afforded every facility for pradising the Art in all its 
branches* 

In addition to the regular College Course in Photography 
occasional classes are formed, consisting each of about 
six gentlemen, who meet twice a week. The fee for 
private instrudion is £$ 5s. for ten lessons, or £10 los. 
for three courses. There is in every case a charge of £1 
each course for chemicals. 

EvEHiNO Classes. 
Classes for Evening Instrudion in various subjeds are 
held during the months from Odober to March, inclusive, 
and during the months of April, May, and June. 

UNIVERSITY COLLEGE. 
FACin*TY OF Science. 
Pro/mor.— William Ramsay, Ph.D., F.R.S. 
Assistant Professor.—]. N. Collie. Ph.D. 
Assistants,-^Uomz Travers, B.Sc., and N. T. M. Wils- 

more, M.Sc. , , ^ r „ n 

The Session is divided mto three Terms, as follows, all 
the dates being inclusive :— _ ' , ., ^.^ 

First Term, from Wednesday, Odober and, until Friday, 
December 2oth ; _ , , ». « ^ „ 

Second Term, from Tuesday, January 14th, I096, till 
Friday, March 27th ; 

Third Term, from Tuesday, April 21st, till Wedn .f day, 
July ist. Class Examinations begin on June i8th. 
yunior Courses, 

First Term : Tuesday and Thursday at 11, and Satur- 
day at 10. Third Term : Tuesday and Thursday at xo, 
Friday at 4. Fee:— j£4 48» . , ,. ,. , 

These Courses will each consist of about thirty lessons, 
partly theoretical and partly pradical, on the non-metallic 
elements. Frequent exercises will be given. 
Senior Course of Chemistry, 

First and Second Terms : The Class meets four times a 
week, on Mondays, Wednesdays, Fridays, and Saturdays, 
at 9, for Ledures, Examinations, and Exercises. 

Fee :— For the Course, £7 7s. ; Perpetual, £g 9s. ; for 
the First or Second Terms, £^ 4s. 

This Course and the Pradical Class cover the subjed 
as prescrit>ed for the Preliminary Scientific (M.B.) and 
Int. Examination in Science of the University of London. 

For the Preliminary Scientific Examination Students 
who take the three subjeds for that examination in July 
attend during the First and Second Terms. 



Schools Of Chemistry. 



f Cbbmical Rawa. 
I Sept 6, 1894. 



Advanced Course of Chemistry, 
Second and Third Terms.— The class meets twice a 
week, on Tuesdays and Thursdays, at 9, beginning on . 
January 14. The hour will be altered by special arrange- 
ment with the class if necessary. 
Fee:— For the Course, £3 3s. ; for a Term, £2 2S. 
This Course will be found suitable for those about to 
proceed to graduation as Bachelor of Science in London 
University, and to those who intend to choose Chemistry 
as a profession. Such students should also work in the 
Laboratory during as many hours as they can spare. 

Organic Chemistry, 

Tuesday and Thursday, at 9, in the First Term ; 
Tuesday, Thursday, and Saturday, at xo, in the Second 
Term ; and Tuesday and Thursday at 9, and Saturday at 
XX, in the Third Term. The hour of meeting will be 
altered should the cltfss desire it. 

This Course of Organic Chemistry is intended for those 
who in studying the subjed have not a Medical Examtoa^ 
tion chiefly in view. Candidates for Honours at the 
Int. M.B. are, however, recomuiended to attend this Course 
instead of the Special Summer Course. 

The Course includes the subjeds required at the B. Sc. 
Examination, Pass and Honours ; but no previous ac- 
quaintance with Organic Chemistry will be expeded of - 
those joining the Class. 

Fee :— For the Course, £6 6s. ; for the Second .ind 
Third Terms, ^4 14s. 6d. ; for a Term, £2 12s. 6d. ; for a 
Second Course, £z 39, 

Practical Class. 

First and Second Terms, Tuesday and Thursday, at it. 

Fee, including cost of materials, £$ 5s. ; for a Second 
Course, £3 3s. 

The Course includes the Pradical Chemistry required 
at the Preliminary Scientific and Intermediate Science 
Examinations. 

Senior Practical Class. 

Wednesdays from 2 to 4 and Saturdays from xo to X2 
during the Third Term ; also Tuesdays and Thursdays 
from IX to X2. 

Fee : — (Including cost of materials) £'5 5s. ; for a Second 
Course, £^ 3s. 

Analytical and Practical Chemistry, 

The Laboratory is open daily from 9 a.m. to 4 p.m., 
Saturdays excepted, from Odober until the middle of 
luly, with a short recess at Christmas and at Easter. 

Fees : for the Session, ;^26 5s. ; six months, ;^x8 iSs. ; 
three months, ;^io los. ; one month, £^ 4s. 

Three specified days a week : — for the Session, £15 15s. ; 
six months, ;£'ii lis. ; three months, £6 6s. ; one mootb, 
£2 I2S. 6d., exclusive of expense of materials. Students 
may enter at any period of the Session. 

The Laboratory Course includes the Pradical Chennxstry 
required at the following Examinations of the University 
of London :— Prel. Sci. (M.B.), Intermediate M.B., Inter- 
mediate Science, B.Sc. 

Students who wish to attend the Ledures on Chemical 
Technology may acquire here the requisite knowledge 
of Pradical Chemistry and Analysis. 

When accompanied by, or preceded by, attendance 00 
the Ledures on Inorganic and Organic Chemistry, the 
Laboratory Course qualifies Students in the application of 
Chemistry to Manufadures, Metallurgy, Medicine, or Agii< 
culture, &c. 

There is also a Chemical Libra.y containing the chief 
Journals and Standard Works on Chemistry. 

Certificates of Honour are granted to competent 
Students on the work done during the Session. The 
Tuffoell Scholarship Gfioo for two years) will also be 
competed for in the Session 1895-96; also the Cloth- 
worker*s Scholarship of £^0, 



CnButcAL News, ' 
Sept 6, 1895. ' 



Schools of Chemistry. 



115 



ROYAL COLLEGE OF SCIENCE AND 
ROYAL SCHOOL OF MINES. 

Professor »^y/. A. Tilden. D.Sc, F.R.S. 

Assistant Profissor.—V/. P. Wynne, D.Sc, A.R.C.S. 

Demonstrators, — H. Chapman Jones and J. W. Rodger, 
A.R.C.S. 

Assistants,— G» S. Newth, W. Tate, A.R.C.S., and A. 
Eiloart, Ph.D., D.Sc. 

The Royal College of Science at South Kensington is 
intended, primarily, for the instrudion of teachers, and of 
stadents of the industrial classes seledled by competition 
in the examinations of the Science and Art Department. 
The Royal School of Mines is incorporated with the Royal 
College of Science. Students entering for the Associateship 
of the Royal School of Mines obtain their general scientific 
training in the Royal College of Science. The instrudlion 
in the Royal College of Science is arranged in such a 
manner as to give the Students a thorough training in the 
general principles of Science, followed by advanced instruc- 
tion in one or more special branches of Science. The 
Associateship is granted in certain divisions or lines of 
study. Students who go through any one of the prescribed 
courses of instruction and pass the necessary Examina- 
tions receive a Certificate of Associateship of the Royal 
College of Science, or of the Royal School of Mines. 
Students who are not candidates for the Associateship 
are permitted to enter as occasional students in one 
or more special branches of science, and on passiug the 
examination receive a Certificate to that effcdl. The 
Associateship of the Royal College of Science is given 
in one or more of the following divisions :— Mechanics, 
Physics, Cheniistr}', Biology, Geology, and Agricultur:, 
and the Associateship of the Royal School of Mines in 
Metallurgy and Mining. 

The course of instruction, which lasts for three years, 
is the same for all the divisions during the first year, after 
which it is specialised in accordance with the Scheme 
detailed in the Prospedus of the School. 

The Session is divided into two Terms. The first Term 
begins on the 2nd of Odober and ends about the middle 
of February. The second Term begins in the middle of 
February and ends about the middle of June. 

Examinations are held at the end of each course of in- 
strudion and at such other periods as may be found neces- 
sary. On the results of these examinations the successful 
candidates are arranged in two classes, first and second. 
There are also '* Honours ** examinations for the subjects 
of the third year, the successful candidates being placed in 
order of merit. A student obtains the Associateship who 
passes in all the subjeds of the first two years and in the 
third year those of the special division he seleds for his 
Associateship. A student who goes through the prescribed 
course of instrudion in any subjed and passes the final 
examination in it receives a certificate to that effed. 

Students who do not wish to attend the lectures are 
admitted for short periods to the laboratories, at the dis- 
cretion of the Professors. The fees for the laboratories 
are £4 per month. 

Students not entering for the Associateship are admitted 
to any particular course of study, so far as there is room, 
on payment of the fees shown in the following table : — 

Lectures. Laboratory. 

Chemistry 3 13 

Physics 5 12 

Biology with Botany .... 5 12 

Geology with Mineralogy • • 4 8 

Mechanics . • 4 6 

Metallurgy 2 13 

Mining 4 

Astronomical Physics .... 2 3 

Agricultural Chemistry, jper term, £13. Mathematics 
and Mechanical Drawing, j£^ per term. Model and Free- 
hand Drawing, £1 per term. Descriptive Geometry, £3 
per session. Mine Surveying, £10, 



The fees for the first two years amount to about 
£75, and for the remainder of the course for the Asso* 
ciateship they vary from £30 to about £40. 

Both the private and the State-aided students are re- 
quired to furnish themselves with certain instruments smd 
apparatus before the commencement of the courses. These 
are enumerated in the syllabuses of the several subjeds. 

Officers of the Army, Navy, and Civil Service, recom- 
mended by their respective Departments, are admitted to 
the Lectures and Laboratories at half fees. 

Associates of the Royal College of Science or of the 
Royal School of Mines have the privilege of free admis- 
sion to the Librar>' and to all the courses of ledures. 

Bona fide teachers cjualified to earn payments for 
teaching Science accordmg to the rule of the Science and 
Art Directory may obtain permission to attend free any 
course of leCtures. 

Several valuable Exhibitions, Scholarships, and Prizes 
are attached to the studentship. 

Summer Courses for Teachers, — Short courses oi in- 
strudion are given annually, about July, in different 
branches of science for the benefit of teachers of science 
schools in the country. The courses last three weeks. 
About 250 teachers are admitted to them, and they re* 
ceive third class railway fare to and from South Kensington, 
and a bonus towards their incidental expenses of £3 each. 
(See Science and Art Dire^ory.) 

Working Men's Lectures, — Notification of these will 
be given in the newspapers. 

THE SCHOOL OF THE 

PHARMACEUTICAL SOCIETY OF GREAT 
BRITAIN. 

The Fifty-fourth Session will commence on Wednesday, 
OAober 2nd, 1895. Entries not previously arranged with 
the Dean or Secretary may be made between 10 a.m. and 
z p.m. on that day. 

Professors and Lecturers, — Prof. Dunstan, M.A., F.R.S., 
Sec. C.S.. F.I.C., Chemistry; Prof. Attfield, Ph.D., 
F.R.S., F.I.C.. Praaical Chemistry; Prof. Green, Sc.D., 
F.R.S., F.L.S., Botany (Dean); Prof. Greenish, F.LC., 
F.L.S., Materia Medica; Mr. Joseph Ince, F.L.S., Phar- 
macy and Practical Pharmacy. 

A Course of LeAures on Physical, Inorganic, and 
Elementary Organic Chemistry commences in Oaober 
and terminates at the end of March. An Advanced 
Course of Ledures on Organic Chemistry begins in April 
and extends to the end of June. The leAures will be 
given at 9.30 a.m. These LeCtures are adapted to the 
requirements of Pharmaceutical and Medical Students, 
and also those who are proceeding to degrees at the Uni- 
versity of London, or who are preparing for the examina- 
tions of the Institute of Chemistry. 

Entries may be made for single classes. A bench in 
the chemical laboratories, which are open daily throughout 
the Session, can be engaged for any period. Certificates of 
attendance at the two Courses of Ledures on Chemistry 
and at the Chemical Laboratories are accepted as evi- 
dence of chemical training by the Institute of Chemistry 
in connection with the Examinations for the Associate- 
ship, and also by the conjoint Board ofthe Royal Colleges 
of Physicians and Surgeons, as well as by other examining 
bodies. 

Prospeduses and further information may be obtained 
from Mr. Ernest J. Eastes, F.I.C, Secretary to the School, 
17, Bloomsbury Square, London, W.C. 

UNIVERSITY COLLEGE OF WALES, 
ABERYSTWYTH. 
University of Wales. 
Professor,— H. LI. Snape, D.Sc, (Lond.), Ph.D. 
(Gcettingen), F.LC. 

Assistant Lecturer and Demonstrator, — A. W. Warring- 
ton, M.Sc. (Vic)., F.I.C. 

Assistant Lecturer in Agricultural Chtmistry,—], Alan 
Murray, B.Sc. (Edin.). 



ii6 



Schools of Chemistry. 



i Cbbmicai. Niwt» 
\ Sept 6, 1804. 



The College is open to male and female students above 
the age of sixteen years. The Session commences on 
Monday, September 30, on which day all Students will 
be expe^ed to meet the Professors in the Library of the 
College. 

Lecture Courses, — (1} Matriculation Course ; three lec- 
tures weekly during the Michaelmas and two weekly 
during the Lent and Easter Terms. (2) Intermediate 
Science Pass Course; four ledures weekly during the 
Lent and Easter Terms. (3) Intermediate Science 
Honours Course ; two ledures weekly during the Lent 
and Easter Terms. (4) B.Sc. Course; three ledures 
weekly throughout the Session. (5 and 6) Courses in 
Agricultural Chemistry. For students in their first year, 
3 leAures, and for those in their and year, 2 ledures weekly 
throughout the Session. 

Laboratory Courses .—The Laboratory is open daily 
from to a.m. to z p.m., and from 2.15 to 5 p.m., except on 
Saturdays. Classes for the Systematic Study of Quali- 
tative and Quantitative Analysis will be formed, and 
Special Courses will be arranged for those who intend to 
follow Medicine or Pharmacy, or any one particular 
branch of Applied Chemistry, always provided that such 
Students possess the requisite knowledge of Theoretical 
Chemistry. The hours will be arranged, as far as possible, 
to suit the requirements of the individual Student. 

The College is recognised by the Royal University of 
Ireland, and by the Colleges of Physicians and Surgeons 
of England, Scotland, and Ireland as an institution at 
which the instrudion necessary for their respedive 
Diplomas in Medicine, in Chemistry, Physics, and 
Biology may be given. One year for graduation in Medi- 
cine and two years for graduation in Science may be spent 
at Aberystwyth. 

Fe€S, — The Fee for the whole Session, if paid in ad- 
vance, is ;f 10 ; if paid by Single Terms, for the first term 
of attendance in each Session, £j^ ; for the second term, 
£^ xos. ; for the third term, £s- These composition fees 
enable the Student to attend any or all the Classes of the 
College, with the exception that a small extra fee is 
charged for Laboratory Instrudion. Thus, for Pradical 
Chemistry, the additional fee is, for six hours* work per 
week, xos. per term, and for twelve hours, 20s. per term. 
The fees for those who desire to spend several days 
weekly in the laboratory may be learned on application 
to the Registrar. Fee for a single Ledure Course £1 
per term. 

Scholarships and Exhibitions varying in value from £10 
to £^ per annum will be offered for competition at 
examinations which commence on September 17, and 
exhibitions are awarded at the end of the Session on the 
results of the class examinations. 

The Chemical Laboratories in connexion with this 
College have been recently built, and are fitted with every 
convenience for the prosecution of chemical studies. 

Intending Students requiring further information are 
recommended to write to the Registrar for a copy either 
of the General Prospedus or of one of the Special Pros- 
peduses issued for the Agricultural and Normal Depart* 
ments. 

UNIVERSITY COLLEGE OF NORTH WALES, 
BANGOR. 

CA#iriff/fy.— Professor, James J. Dobbie, M.A., D.Sc. 
Demonstrator, Fred. Marsden, Ph.D., B.Sc. Assistant 
Lecturer in Agricultural Chemistry, F. V. Dutton. 

PA>^Wcj.— Professor, Andrew Gray, M.A., F.R.S.E. 

The Session opens 0<5tober and, 1895. All regular 
classes are open to men and women students above the 
age of 16 years. The following Courses of Lectures will 
be given. 

Matriculation Course. — Subjeds: Those prescribed for 
the London University Matriculation Examination. Fee 
for the Term £2 2S. A class for revision of Matriculation 
Work will be held during the Summer Term. Fee for 
he Term, £1 is. 



Intermediate Course, — Inorganic Chemistry and 
Elementary Physical Chemistry. Fee for the Term 
£2 2S. 

B.Sc, Course, -^Orgskuic Chemistry. Fee for the Session, 

£338. 

Medical Course. — Inorganic and Organic Chemistry. 
Fee for the whole Course, £4 4s. 

Agricultural Chemistry. — Fee, £2 28. 

Laboratory Courses, — The laboratory is open on five 
days of the week from 10 a.m. to 4 p.m. for instrudion in 
Chemical Analysis and in the Application of Chemistry 
to Medicine and the Industrial Arts. Fees : six hours 
per week, £1 is. per Term; twelve hours, £2 2S. ; 
eighteen hours, £3 3s. ; twenty-four hours, £4 4s. Com- 
position Fee for all Laboratory Classes of the Intermediate 
Science Course taken in one year, £4. 4s. 

The Chemistry, Botany, Zoology, and Physics Courses 
are recognised for Medical graduation in the Universities 
of Edinburgh and Glasgow, and students can make one 
Annus medtcus at the college. The Science Courses are 
recognised for part of the science degree course of the 
University of Edinburgh. 

UNIVERSITY COLLEGE OF SOUTH WALES 
AND MONMOUTHSHIRE, CARDIFF. 

Professor.^C, M. Thompson, M.A., D.Sc, F.C.S. 

Demonstrators, — E. P. Perman, D.Sc, F.C.S., and 
A. A. Read, F. I.e., F.C.S. 

The Session commences Odober 7th, and terminates 
on June 26th, and is divided into three terms. 

The Junior Course (delivered during the Michaelmas 
term only) consists of about 50 ledures, and will cover the 
subjeds prescribed for the Matriculation examinations of 
the University of Wales and the University of London. 
Fee, £2 2s. A revision class is held in the Summer term. 

The Intermediate Course consists of about 80 ledures 
held during the Lent and Summer terms in continua- 
tion of the Junior Course, and is the qualifying course fur 
the Intermediate Examination of the University of Wales. 
Together with laboratory pradice, it will cover the sub- 
jeds required for the Intermediate Examination in 
Science and the Prel. Sci. (M.B.) Examination of the 
University of London. Fee, £4 4s. 

The Senior Course consists of some 90 le^res deroted 
to Organic Chemistry ; Fee,^3 38. 

A course of 20 ledures on Qualitative Analysis will also 
be given. 

The following ledures on Metallurgy will be given by 
Mr. Read :— 10 ledures on Fuel ; Fee, los. 6d. 20 lec- 
tures on General Metallurgy; Fee,£i is. 30 leaureson 
the Manufadure of Iron and Steel ; Fee, £1 is. A prac- 
tical course on Iron and Steel Analysis will also be held. 

In the laboratory each student works independently, so 
that the course of study may be adapted to the require- 
ments of the individual. Hours, 9 to x and 2 to 5 ; Satur- 
day, 9 to I. Fees— Six hours per week, £3 3s. per session ; 
twelve hours, £2 2S. per term; eighteen hours, £^ 38. 
per term ; twenty-four hours £4 4s. per term. 

Registered medical students can prepare for the Inter- 
mediate M.B. Examination of the University of London, 
and spend three out of their five years of medical study 
in Cardiff. Medical students wishing to graduate at a 
Scottish University, or preparing for a Conjoint Board 
Surgical and Medical Diploma, or for the Diploma of the 
Society of Apothecaries, can spend two years in Cardiff. 
For further information see the prospeAus of the Faculty 
of Medicine, which may be obtained from the Registrar. 

The College is recognised as an institution at which 
two years of the course for the degree of Bachelor of 
Science of the University of Edinburgh may be spent. 

Students by making a payment of £10 at the com- 
mencement of each session may compound for all ledure 
fees for the whole session. Laboratory fees are not in- 
cluded in the composition fee, but Students preparing for 
the Science Examinations of the University of London 



CsmntCAi. Niwi, I 
Sept. 6, 1895. I 



Schools of Chemistry. 



117 



maj, by making a payment of £1^ 138. at the com- 
mencement of each Session, compound for both Le^ure 
and Laboratory Fees during the Session. 

At the entrance examination in September, and the 
annual eaamination in June, several scholarships and 
exhibitions are awarded. .Great importance is attached 
to special excellence in one subjea. 

The Collegs ProspedD^. oai slso further information as 
to scholarships, may be obtained from the Registrar. 

A Hall of Residence for Women Students is attached to 
the College. 

UNIVERSITY COLLEGE, BRISTOL. 

Professor t/ Chemistry, —Sydnty Young, D.Sc, F.R.S. 

Lecturer, — Arthur Richardson, Ph.D. 

The session 1895-96 will begin on Odober 4th. Lectures 
and classes are held every day and evening throughout 
tbe Session. In the Chemical Department leAures and 
classes are given in all branches of theoretical chemistry, 
and instru^on in pradical chemistry is given daily in the 
chemical laboratory. The department of experimental 
physics includes various courses of ledures arranged pro- 
Igressively, and pradical mstrudion is given in the physical 
and eledrical laboratory. The Department of Engmeering 
and the Construdive Professions is designed to afford a 
tbofongh scientific education to students intending to 
become engineers, or to enter any of the allied professions, 
and to supplement the ordinary professional training by 
systematic technical teaching. This department includes 
courses specially arranged for students intending to 
become civil, mechanical, eledrical, or mining engineers, 
sarveyor8,|orarchiteds. Those who attend the mechanical 
engineering course enter engineering works during the 
six sammer months, and, in accordance with this scheme, 
various manufaAuriug engineers in the neighbourhood 
have consented to receive students of the College into 
their offices and workshops as articled pupils at reduced 
terms. Medical education is provided by the Faculty of 
Medicine of the College. Several Scholarships are tenable 
at tbe College. Full information may be obtained from 
the Secretary. 

Day Lbcturbs. 
Inorganic Chemistry, 

The Courses treat of the principles of Chemistry, and of 
tbe Chemistry of the Non-Metals and Metals. 

yunior Course.'^Two LeAures a week will be given 
daring the First and Second Terms. 

Senior CoHrj#.— Three LeAures a week will be given 
throughout the Session. 

Adoanced Conn/.— One Ledlure a week will bo given 
throughout the Session. 

Organtc Chemistry, 

This Coarse will relate to the more important groups of 
the Compounds of Carbon. 

Two Ledures a week will be given during the Second 
Term, and three Ledures a week during the Third Term. 
Fee, £^ 3s. An advanced course of ledures will alsa be 
given one day a week during the session. 

Practical Chemistry, — Laboratory Instruction. 
The Laboratory will be open daily from zo a.m. to 5 
p.m., except on Saturdays, when it will be closed. Instruc* 
tion will be given in the Laboratory in all branches 
of Pradical Chemistry, including Qualitative and Quanti- 
tative Inoreanic and Organic Analysis, the preparation of 
Chemical Produds, and Inorganic and Organic Research. 
Special facilities will be affonled to those who desire to 
study Pradical Chemistry as applied to the different pro- 
cesses employed in the Arts and Manufadures. The 
Laboratory is under the immediate supervision of the 
Professor and the LeAurer. Fees in Guineas — 

5 Days a 4 Days a 3 Days a aDajs a t Dav a 



Week. 


Week: 


Week. 


Week. 


Wee 


Per Session . * • • 15 


"J 


10 


7i 


5 


„ Two Terms.. 11 


9 


7* 


5i 


3i 


„ One Term .. 7 


6 


4i 


31 


3i 



Students may arrange to divide their days of laboratory 
work into half-days. 

Chemical Scholarship, — Among others, a Chemical 
Scholarship of ;f25 is onered for competition. 

EvENiNO Lectures. 

Two courses of Ledures will be delivered daring 
the First and Second Terms ; they will be devoted to the 
consideration of the general Principles of Chemistry and 
Chemical Physics and the Chemistry of Non-Metallic 
and Metallic Elements. Special attention will be paid 
throughout to those produds which have a pradical 
application in the Arts and Manufadures. Fee for each 
course, 7s. 6d.- 

University College, Bristol, has been approved by the 
Council of the Institute of Chemistry as a College at 
which all the subjeAs required for the admission of 
Associates to the Institute are taught. 

MASON COLLEGE, BIRMINGHAM. 

Pro/^Mor.— Percy F. Frankland, Ph.D., B,Sc., F.R.S. 

Assistant Lecturer,^Q, F. Baker, Ph.D., B.Sc. 

Demonstrator, ^D, R. Boyd, B.Sc. 

The Session will be opened on Odober ist, 1895. 
Elementary Course, 

Forty Le^ures adapted to the requirements of beginners 
will be given in the Winter and Spring Terms. LeAure 
days — Wednesdays and Fridays at zz.30. 

Persons entirely unacquainted with Chemistry are 
recommended to attend this Course before entering for 
the General Course. Candidates for the Matriculation 
Examination of the University of London also are advised 
to attend this Course. 

General Course, 

The General Course of Ledures on Chemistry will be 
found useful by Students who are afterwards to become 
Engineers, Archite^, Builders, Brewers, or Manufac- 
turers (such as Metallurgists, Alkali, Soap, Manure, 01ass« 
or Cement Makers, Bleachers and Dyers, &c.) 

Students preparing for the Intermediate nxamination 
in Science and Preliminary Scientific (M.B.) Examination 
of the University of London should attend the Ledures 
on Inorganic Chemistry (Winter and Spring Terms). 

Candidates for Intermediate Examinations in Medicine 
will in general require only that part of the course 
(Summer Term) which relates to Organic Chemistry. 

The full course, extending over three terms, will also 
satisfy the requirements of Students preparing for tbe 
Associateship of the Institute of Chemistry, so far at 
attendance at ledures on General and Theoretical 
Chemistry is concerned. 

1. From Odober to March (Winter and Spring Terms). 
About eighty ledures on Inorganic Chemistry and 
Chemical Philosophy will be given on Mondays, Tuetdayt* 
Wednesdays, and Thursdays from October to December, 
and on Mondays, Tuesdays, and Wednesdajrs from 
January to March, at 9.30 a.m. A Tutorial Class is held 
m coonedion with this Course once a week throughout 
the Session. Fee, £5 5s. for the course. 

2. May to July (Summer Term). About thirty ledurei 
will be given on Elementary Organic Chemistry, or the 
chemistry of tbe most important series of carbon com- 
pounds. This course will include all the subjeds required 
for the Intermediate Examination in Medicine of the Unl* 
versity of London. Ledure Days — Monday, Wednesday, 
and Friday at 11.30 a.m. Fee, £1 izs. 6d. 

The General Course (including Inorganic and Organic 
ledurei) qualifies for graduation in the medical faculties 
of the universities of Edmburgh, Glasgow, Aberdeen, and 
Durham. 

Advanced Course, 

An Advanced Course for the study of Theoretical 
Chemistry and those parts of the tubjed which are 
required for the degree of B.Sc. in the University of 
London will meet twice a week. Pee for the seMton 
£3 1«- 



ii8 



Schools of Chemistry. 



f OBmmcALMBWt, 
1 Sept 6, X895. 



Laboratory Practia, 

The College Laboratory is open daily from 9.30 to 
5, except on Satardays, when it is closed at i p.m. 

Candidates for Intermediate Examination in Science, 
Preliminary Scientific (M.B.), B.Sc, and Intermediate 
Examination in Medicine of the University of London, 
may obtain in the Laboratory of the College the instruc- 
tion necessary. The three months Course of Pradical 
Chemistry for the B.Sc, Edinburgh, in the department 
of Public Health, may be taken m. the Mason College 
Laboratory. Fees :— 

.,,..„ Three houn 

^^^■y- per day. 

One Term 7 guineas •• .« 4! guineas. 

Two Terms • • • • 13 n • • • • 84 „ 

Tfareee Terms .. .. z8 „ .. •• 12 „ 

A Course of short demonstrations and exercises is 
given by the Professor or one of his Assistants once a 
week. All first-year Students are required to attend, 
unless estempted for special reasons by the Professor. No 
Fee. 

Miiallurgy. 

Three Courses of Ten Ledures will be given on the 
Principles and Pradice of Metallurgy. Fee, zos. 6d. for 
each of the first two courses, and for each of the two sec- 
tions of the third course. A more advanced course of 
about sixty ledures upon seleded subieAs is also given by 
Mr. McMillan, the LeAurer in Metallurgy. 

There is a separate laboratory for metallurgical students 
in which provision is made for fnstruaion in assa3ring, &c. 

Evening Clastts. 

Several Courses of Evening LeAures are arranged 
during the Winter and Spring Terms of each session. The 
subjeds are treated in a less technical manner and the 
fees are nominal. 

Scholarships, 
' PriistUy Scholarships,— Three Open Scholarships in 
Chemistry of the value of £zoo each are awarded annually 
in September. 

Bowtn Scholarship, — One Open Scholarship in Metal- 
lurgy of the value of ;Cioo is awarded annually in Sep- 
tember. 

Forsttr Research Scholar ship, —K Scholarship of the 
value of £50 is annually awarded. 

For particulars apply to the Registrar. 

Excursions. 
During previous Sessions permission has been obtained 
to visit some of the great fadories in or near Birmingham, 
in which chemical and metallurgical industries are carried 
on. Students have thus had most valuable opportunities 
of gaining a pradical acquaintance with some branches of 
Applied Science. The privilege thus courteously granted 
by several manufadurers will, it is hoped, be enjoyed in 
every future Session. The excursions will be conduded 
by the Professor or Ledurer. 

BRADFORD TECHNICAL COLLEGE. 
Chemistry and Dvbing Department. 

Professor,— (Vacant) . 

Demonstrator,— ^9LQtkTi\), 

Lecturer on Botany and Materia Medica, — William 
West, F.L.S. 

The school year is divided into three terms. The 
Session commences on September i6th and terminates on 
July 22nd. The course of instrudion extends over two 
years, and embraces Le^ure Courses on Inorganic and 
Organic Chemistry, the technology of the textile fibres, 
mordants, natural and artificial colouring matters, 
technical analysis, and laboratory pradice in analytical 
chemistry, chemical preparations, and dyeing. Inclusive 
fee, £^ 48. per term. 

During the first and second terms Evening Classes are 
held for the benefit of persons engaged during the day and 
for pharmaceutical students. 



ROYAL AGRICULTURAL COLLEGE, 

CIRENCESTER. 

Chemical Department. 

Professor,— ?to{, E. Kinch, F.C.S., F.I.C. 

Assistants,— Cecil C. Duncan, F.I.C, and W. James. 

Systematic courses of Ledures are given on the various 
branches of Chemistry in its relation to Agriculture, illus- 
trated by experiments, and by the coUedions in the College 
Museum. They comprise the laws of Chemioil 
Combination and the general Chemistry of mineral 
bodies, and of the more frequentlv occurring bodies of 
organic origin, with the relationships of their leading 
groups ; and, finally, the applications to pradical opera- 
tions of the Chemistry of the atmosphere, of soils and 
manures, of vec^etation and stock feeding, and of the pro- 
cesses and produds of the dairy. 

In the Laboratorv pradical instrudion is given in 
the construdion and use of apparatus and in Chemical 
manipulation and analysis, both qualitative and quantita- 
tive. After studying the simple operations and the 
properties of the commonly occurring substances, the 
Students are taught to analyse a series of compounds, 
and apply the knowledge thus obtained to the ansilysis of 
manures, soils, waters, feeding stuffs, dairy produds, and 
other substances met with in the ordinary course of Agricul- 
tural pradice. Chemico-agricultural researches are under- 
taken by the senior Students under the diredion of the 
Professor and his Assistants. 

VICTORIA UNIVERSITY. 
THE YORKSHIRE COLLEGE, LEEDS. 

Professor of Chemistry, — Arthur Smithells, B.Sc. Lond., 
F.I.C. 

Lecturer in Organic Chemistry, — ^Julius B. Cohen, Ph.D., 
F.I.C. 

Assistant Lecturer in Agricultural Chemistry, — Herbert 
Ingle, F.I.C. 

Demonstrators,— A, C. Wright, B.A., and T. Ewan, 
Ph.D., B.Sc. 

The Session begins Odober 8, 1895. 

Lecture Courses, 

1. General Course of Chemistry. — Monday, Wednesday 
and Friday, at zi.30 a.m., from Odober to the end of the 
second term, and during part of the third term. Fee for 
the Course, £4 4s. 

2. Inorganic Chemistry. — First year Honours Course, 
Non-metals. Monday, Wednesday, and Friday, at 9.30 
a.m. Fee, £3 13s. 6d. 

3. Inorganic Chemistry. — Second year Honours 
Course, Metals. Tuesday, Thursday, and Saturday at 
9.30 a.m. Fee, £3 13s. 6d. 

4. Organic Chemistry. — Tuesday, Thursday, and 
Saturday at 12 noon Fee £3 13s. 6d. 

5. Organic Chemistry Honours Course. — Wednesday 
and Friday at 12 noon. Fee, £2 Z2S. 6d. 

6. Theoretical Chemistry. — Advanced Course. Tuesdays 
and Thursdays at 9.30 a.m. Fee, £2 12s. 6d. 

7. Chemistry as Applied to Coal Mining. — Tuesday 
during the First Term, at 4 p.m. 

8. Agricultural Chemistry.— Monday, Tuesday, and 
Friday, at 3 p.m., during first and second terms. 

9. Chemistry for Teachers.— Saturdajrs from 9.30 to 
12.30 in the first and second terms. Fee, £4 4s. 

Laboratory Courses, 

The College Laboratory will be open daily from 9 a.m. 
to I p.m., and from 2 to 5 p.m., except on Saturdays, 
when it will close at x p.m. 

Fees for the Session- -Students working six days per 
week, ;f2i ; five. £18 i8s. ; four, ;f 16 i6s. ; three, ;f 13 13s. 

Class in Practical Chemistry^ Saturday mornings, from 
9.30 to 12.30. Fee £1 1x8. 6d. 

Practical Chemistry for Medical Students, — Tuesdays, 
9.30 to XX.30 Odober to end of December; Thursdays, 
2 to 4 from January to end of March. 



CataieAL If bws, i 
8«pt. 6. 1895. f 



Schools oj Chemistry. 



119 



PrtutUat Conns in Sanitary Chemistry, — At timet to 
be arranged. 

Practical Organic Chemistry for Medical Students^—At 
times to be arranged. 

Evening Clots. 

A Course of twenty Leaurei by Mr. Ingle, on the 
Chemist^ of Combustion will begin during the first and 
sccood Terms, on Wednesdays, at 7.30 p.m., beginning 
Odober 10. Fee, loe. 6d. 

Dyeing Department* 

Prcfesuff.'-J, J. Hummel. F.I.C. 

Lecturer and Research Assistant, — A. O. Perkin, 
F R.S.B. 

Assistant Lecturer. "-V/. M. Gardner. 

This Coarse extends over a period of three years, and 
is intended for those who wish to obuin a full scientific 
and pradical education in the art of dyeing. It is suitable 
for those who purpose in the future to uke any part in 
the direaion of the operations of dyeing or printingr of 
textile fat>ric8, e,g.t the sons of manutadurers, calico 
printers, managers, master dyers, Ac, 

Leather Industries Department, 

Lecturer.^H. R. Proaer. F.I.C. 

The full Course, which extends over a period of three 
years, is suitable to all who intend to become Technical 
Chemists in the Leather Industry, or managers of im- 
portant works, and is recommended to sons of tanners. 
The Courseinclttdes instraaion in chemistry, engineering, 
leather manufaaure, and praaical work m the Leather 
Indostries Laboratory. 

Agricultural Department. 

Pro/rjsor.— James Muir. 

The full Course occupies two years, and includes in- 
•tniaion in chemistry, physics, botany, engineering and 
surveying, and the principles of agriculture, as well as 
praaical work in the various laboratories and out-door 
agrtcultare. 

Research Students are admitted to the College 
Laboratories on reduced terms. 

Several valuable Scholarships are at the disposal of the 
College, vis., the Cavendish, Salt, Akroyd, Brown, Emsley, 
Craven, and Clothworkers* Scholarships, and the Leighton 
Trastees' Exhibition, and one of the 1851 Exhibition 
Scholarships. The West Riding County Council Scholar* 
•hips are tenable at the Yorkshire College. 

UNIVERSITY COLLEGE, LIVERPOOL. 

Professcr.-~J, Campbell Brown, D.Sc. 

Lecturer on Organic Chemistry, --C A. Kohn, B.Sc, 
Ph.D. 

Lecturer on Metallurgy,— T, L. Bailey. Ph.D. 

Demonstrators and Assistant Lecturers,— T. L, Bailey, 
Pb.D., C. A. Kohn, B.Sc., Ph.D., and S. B. Schryver, 
B.Sc., Ph.D. 

Assistant.-H. H. Froysell. 

The Session commences Oaober 3rd. 

The Classes meet the requirements of candidates for 
the Ordinary B.Sc. Degree, for Chemistry Honours, or 
for the M.Sc.or D.Sc Degree in Viaoria University ; for 
Degrees in Medicine of Viaoria, London, and Edinburgh ; 
for a special Technological Certificate of University Col- 
lege ; and for those studying Chemistry as a preparation 
for professional, technical, or commercial life. The Classes 

2oalify for the Fellowship of the Institute of Chemistry of 
frieat Britain and Ireland, and other Examination Boards. 

Lecture Courses, 

General Blementarv Course on the principal non* 

metallic elements and the most important metals, the 

principles of Chemical Philosophy, and an introduaory 

•ketch of Organic Chemistry. Three Terms. Fee, £4. 

Engineer*s Course of Leaures with Praaical Class. 

Two Terms. Fee, ;f4« . « ^. • „ .- 

Dental Course, Leaures and Praaical. Fee, £$ 5s. 
Coarse A.— Non-metals. Fee, £1 los. 



Course B.— Metals. Fee, £3 los. 

Course C— Organic Chemistry. Fee, £^ los. 

Course H. — Special Organic Subjeas. Fee, £1, 

Course D.^-Physical Chemistry. One Term. Fee,£i. 

Course E.— History of Chemistry and of the Develop- 
ment of Modern Chemical Philosophy. Three Terms. 
, Fee. £2. 

Courses F. — Technological Chemistry and Metallurgy : 
Leaures on Technology are given in conneaion with 
Laboratory work at hours to be arranged. The subjeas 
are varied in different years, (i) Alkali and Allied Manu- 
laaures. (2) Copper, Iron, and Steel. (3) Lead, Silver 
and Gold. Alumjnium. and other Metals. (4) Distillation 
of Coal and Tar Industries. (5) Fuel and Gas. (6) 
Chemistry Applied to Sanitation. (7) Technical Gas 
Analysis. Three terms. Fee, etch course £1 los. 
Practical Classes. 

(z) Junior. (2) Intermediate: Qualitative Analysis of 
Inorganic Substances and of some of the more common 
Organic Substances. (3) Revision Class. (4) Senior: 
Praaical Organic (Advanced Medical Class). (5) Praaical 
Exercises on Technology, Pharmaceutical Chemistry, 
Saitanry subjeas. Examination of Water and Air, of 
Animal Secretions, Urinary Deposits, Calculi, and 
Poisons. (6) Quantitative Class: Course arranged to 
suit the requirements of the London University B.Sc. 
Examinations, Pass and Honours, and for Intermediate 
M.B. Honours. 

Chemical Laboratory. 

The Chemical Laboratories provide accommodation for 
every kind of chemical work. 

Additional metallurgy furnaces have been built, and a 
department for praaical study of Elearicity applied to 
Chemical Analysis has been added during the past year, 
and a large extension of the laboratories is in progress 
this year. 

Students desirous of gaining a thorough theoretical and 
praaical acquaintance with Technical Chemistry, or who 
intend to adopt Chemical work as a profession, most 
devote three or four years to special study. 

Table of Febs. 

One Tero. Three Tennt, 

Per Week. Three Mooths. One ScMioa. 

One day £4 £S 

Two dajTS 6 10 

Three days 8 za 

Four days .••••• 9 25 

Whole week xo lot. ai 

Pharmaceutical Coarse, £11. 

Technological Curriculum, 
Preliminary y#ar. ^Chemistry, the Elementary Course. 
Praaical Classes z and 2. Mathematics, or Mechanics, 
or Physics. Elementary Engineering, Drawing, and 
Design (in this or one of the following years). German. 
Or the Viaoria Preliminary Course and Examination 
may be taken. 

First Year, — Chemistry — Courses A and B ; Chemical 
Laboratory three days per week; Praaical Organic 
Class dunng the Summer Term ; Technological Che- 
mistry, Course F. Physics, with laboratory work, one 
day per week. Mathematics (intermediate). German. 
Engineering, First Year Course, Autumn and Lent Terms. 
Intermediate B.Sc Examination may be passed. 

Second Year, — Chemistry. Leaure Course C, on Organic 
Chemistry. Leaure Course E or D, Technological Chemis* 
try. Course F, on Metallurgy. Chemical Laboratory, four 
pays per week. Engineering, Mathematics, or Physics (Ad« 
vanced). The Final Examination for the Viaoria B.Sc., 
or the Intermediate Examination of the Institute of 
Chemistry, may be taken. 

Third Year.—Co\itt% D, F, and C. Any other 
Courses omitted in a previous year. Laboratory, five 
davs per week. Students may finally choose a special 
subjea either of research or of applied Chemistry. 
The Final Examination for the Associateship of the 



120 



Schools of Chemistry. 



I Chemical News, 
I Sept. 6, 12^5. 



Institute of Chemistry of Great Britain and Ireland may 
be taken. Three years study after passing the Preli- 
minary Examination of ViAoria University are required 
for the B.Sc. Degree in the Honours School of Chemistry. 

The Sheridan Muspratt Chemical Scholarship of ;£'5o 
per annum, tenable for two years, will be competed for in 
December, 1895, on an Examination in subjects which are 
included in the first two years of the above curriculum. 
Other Scholarships, Entrance Scholarships, and Free 
Studentships are also available to Students. 
Evening Classts, 

Classes will be held on Metallurgy and on Analysis of 
Oases. 

The Prospedus containing full particulars may be 
obtained from the Registrar, University College, Liverpool. 

LIVERPOOL COLLEGE OF CHEMISTRY. 

/'riwci^a/.— George Tate, Ph.D., F.I.C., F.C.S. 

The Laboratories are open daily from 10 to 5, excepting 
Saturdays, when they close at i p.m. The course of in- 
Btrudtion is adapted to the requirements of students of 
Chemistry as a science, and in its applications to chemical 
and metallurgical industries. The fee for a three years' 
course of study is eighty guineas, or per session of 
three months eight guineas . 

Prospeduses, containing full particulars of the day and 
evening classes, may be had on application at the College. 

DURHAM COLLEGE OF SCIENCE, 
NEWCASTLE-ON-TYNE. 
Professor of Chemistry, — P. Phillips Bedson, M.A., 
D.Sc, F.I.C., F.C.S. 
Lecturer in Chemistry— S&ville Shaw, F.C.S. 
Lecturer in Agricultural Chemistry,— -R, Greig Smith, 
B.Sc. (Edin.), F.C.S. 
The Session will commence on September 23rd, 1895. 

1. Oemral Course, — This Course of Ledures will 
extend over the three terms of the Session, and is 
intended to serve as an introduction to the Science. 
The Ledures will be of an elementary charader, and 
whilst framed to meet the requirements of First Year 
Students will also be serviceable to such as intend pursuing 
Chemistry in its various applications in the arts and 
manufadures, as, for instance. Brewing, Metallurgy, the 
Manufadure of Soda, Soap, Glass, &c. The subjeds 
treated will include an exposition of the Principles of 
Chemistry, and a description of the preparation and 
properties of the chief Elementary Substances, both 
metallic and non-metallic, and their more important 
native and artificial compounds. A sedion of this Course 
will be devoted to an outline of Organic Chemistry. The 
class will meet on Mondays, Wednesdays, and Fridays, 
at zi a.m., and will commence on Wednesday, Odober 
and. Fee, £^ los. for the Session. 

2. Advanced Course, — Inorganic Chemistry, Tuesdays 

3 to 4 p.m., during the Session. Fee, £2 ; or for students 
taking Organic Chemistry, £1, 

3. Organic Chemistry, — A Course of Ledures will 
be given throughout the Session, the subjed of 
which will be Organic Chemistry, or the Chemistry 
of the Carbon Compounds. This class will meet on 
Tuesdays and Thursdays, at 11 a.m., and Fridays 3 to 

4 p.m., and will commence on Thursday, Odober 3rd. 
Fee, £^ los. for the Session. 

Advanced Classes will be formed for the study of 
Inorganic, Organic, and Theoretical Chemistry. Fee for 
the course, £3 los. 

A Ledure Course in Analytical Chemistry will be given 
on Mondays, at 3 p.m., commencing Odober 8th. 

Metallurgy and Assaying. — Ledurer, Saville Shaw, 
F.C.S. A Metallurgical Laboratory is provided, in which 
instrudion is given in the ordinary processes of Dry- 
Assaying, and in the preparation and analysis of Alloys, 
&c. Fee as for Chemical Laboratory. 

Agricultural Chemistry. — The instrudion in this branch 
of Chemistry will consist of a series of Ledures and of 



special pradical work in the Chemical Laboratory. 
Students will be expeded to have a knowledge of Ele- 
mentary Chemistry, such as may be obtained by attending 
the General Course. 

The Ledure Course in Agricultural Chemistry is 
arranged for two days a week throughout the Session. 
Fee, ^3 10. 

Practical Chemistry,— Tht Laboratory is open from 
10 a.m. to I p.m., and from 2 to 5 p.m., except on Satur- 
days, when it closes at z p.m. Laboratory Fees, — Students 
working two days, £2 zos. per term, £6 per session ; one 
day per week, j^i los. per term, £^ zos. per session. 

Courses of Study, — Students will be divided into two 
classes: — (i) Regular, or Matriculated Students, who 
are also Members of the University of Durham ; and 
(2) Non-Matriculated Students. Regular Students will be 
required to follow such a course of study in the subjeds 
professed in the College as will enable them to pass the 
Examinations for the title of Associate in Physical Science 
of the University of Durham. Non-Matriculated Students 
will attend such classes as they may seled. Every can- 
didate for admission as a matriculated student must pass 
an examination on entrance, in reading, writing from 
didation, English or Latin Grammar, arithmetic 
(including decimals), and geography. Registered students 
in medicine are exempted from this examination, or stu- 
dents who produce a certificate of having passed either 
of the two following examinations : — 

z. Durham Examination for certificate of proficiency 
in General Education, held in March and September. 

2. Durham Examination for Students in Arts in their 
first year, or any examination of a similar nature that may 
be accepted by the Council. 

Associateship in Physical Science. — Every candidate for 
the Associateship in Physical Science will be required to 
satisfy the examiners in — Mathematics, Physics, Che- 
mistry, and either Geology or Natural History— in an 
examination to be held at the end of the candidate's first 
year. Associates in Science are admissible one year after 
obtaining the title of Associate to examination for the 
degree of Bachelor of Science of the University of Durham. 

Exhibitions, — Three Exhibitions of the value of ;C25, 
£z5, and £zo respedively will be awarded in Odober next 
to Candidates desirous of attending the first year course of 
study in the College. 

The examination will be held at the College, and wU 
commence on Monday, September 23rd. 

Evening Lectures. — Courses of Evening Ledures will 
be given, with a Pradical Class for Laboratory instrudion. 

Two Exhibitions of £1$ each will be awarded at the next 
examination of '* Persons not members of the University," 
which will be held at Durham in March next. 

Several other valuable Scholarships are available for 
students. 

OWENS COLLEGE, 
VICTORIA UNIVERSITY, MANCHESTER, 

Professor and Director oj the Chemical Laboratory. — 
Harold B. Dixon, M.A., F.R.S. 

Professor of Organic Chemistry, — W. H. Perkin, Ph.D., 
F.R.S. 

Demonstrators and Assistant Lecturers, — George H. 
Bailey, D.Sc, Ph.D. ; Arthur Harden, M.Sc, Ph.D. ; P. 
J. Hartog, B.Sc; B. Lean, B.A., D.Sc; and W. A. 
Bone, B.Sc, Ph.D. 

Lecturer in Dyeing and Printing. — Ernest Bentz. 

Assistant Lecturer in Metallurgy. — Gilbert J. Fowler, 
M.Sc 

The Session begins on Odober z, Z895, ^^^ ends on 
June 23, Z896. 

The instrudion is given by means of ExperimeDtal 
Ledures and Tutorial Classes. The Chemical Classes 
form part of the Courses for Chemistry in the University. 

Chemistry Lecture Courses, 
General Chemistry Course. — Tuesdays, Thi^rsdays, and 
Saturdays, at 9.30, during the two Winter '^ 



liter ^ftraiE. 



CBMIICAL NtWBf I 

Sept. 6, 1895- I 



Schools oj Chemistry. 



121 



Iittroduction to Organic CA#mii^i7.— Wednesdays and 
Fridays, at 9.30, during Lent Term. 

These courses are intended for Medical Students and 
others beginning the study of chemistry. 

First Year Honours Course, — Mondays, Wednesdays, 
and Fridays, ix.30 a.m., during the two Winter Terms. 
The Non-Metals. 

Second Year Honours Course. — Mondays, Wednesdays, 
Fridays, 3.30 p.m., during the two Winter Terms. The 
Metals. 

Third Year Honours Course, — At times to be arranged. 
Physical Chemistry. 

Organic Chemistry {Oeneral). — Tuesdays and Thurs- 
days, 9 30, during two Winter Terms. 

Organic Chemistry (Honours). — Mondays and Fridays, 
9.30, during the two Winter Terms. 

History of Chemistry and Chemical Philosophy, — 
Wednesdays, zo.30, during the Session. 

Metallurgy, — Lectures : The Metallurgy of Copper, 
Lead, Silver, Gold, and the Metallurgy of Iron and Steel 
will be given in alternate years. Practical : Saturdays, 
9.30. 

The Chemical Laboratories are open daily from 9.30. 
a.m. to 4.30 p.m., except on Saturdays, when they are 
closed at 12.30 p.m. 

Courses for B,Sc. Degree. — To qualify for the B.Sc. 
Degree of the Vidoria University, Students have to 
attend a prescribed course of study extending over three 
years, and to pass the Preliminary Examination of the 
University either on entering or at the end of a year*s 
Course. 

The Honours Course of Chemistry is as follows : — 
First year: First year Honours Ledtures; Mathematics 
<3 hours a week) ; Physics (3 hours a week) ; a Language 
(3 hours a week) ; Chemical Laboratory (3 days per 
week). Second year : Second year Honours Ledures ; 
General Organic Ledures ; Applied Chemistry LeAures ; 
Physics Laboratory (i day per week) ; Chemical Labora- 
tory (3 days per week). Third year: Third year Honours 
LeAures; Honours Organic Ledures; History of Che- 
mistry Ledures; Chemical Laboratory (5 days per week). 

The following awards are made to successful Students 
in the Honours Examination :— A University Scholarship 
^^ £5^ f A Mercer Scholarship of £25, A University 
Fellowship of £150 is awarded annually among the 
Graduates in Science for the encouragement of Research. 
Among the College Scholarships open to Chemical 
Students are the Dalton Chemical Scholarship, £$0 per 
aonam for two years ; the 1851 Exhibition Scholarship ; 
the John Buckley Scholarship ; &c. 

Applied Chemistry. 

First Course, — Sulphuric Acid and Alkali Manufadures. 
General Principles of Chemical Engineering. 

Second Course,— Tht Chemistry of Fuel. The Manu- 
adure of Illuminating Gas and Gaseous Fuel. 

Third Coiiri£.— The Chemistry of Coal Tar. 

Fourth Course. — Natural and Artificial Dye-stuffs. 

Fifth C<mr«^.— Calico-printing. 

Certificates in Applied Chemistry. 

The course extends over a period of three years, and 
comprises systematic instrudion by means of ledures and 
pradical work in the laboratories. 

Before admission to the first year's course students are 
required to give such evidence of elementary knowledge 
of Mathematics and Chemistry as shall be considered 
•atisfadory by the Senate. 

The first year's course is the same for all students 
working for the certificate. 

In the second and third years a choice may be made 
between Inorganic and Organic Chemistry. By this 
division of the subjed a student wishing to apply himself 
specially to the inorganic side of the science, may attend 
during his second year the Honours course in Metals, and 
courses on Geology or Mineralogy, and during his third 
year, courses on Metallurgy and on Geology or 



Mineralogy; while a student wishing to apply himself 
specially to the organic side of the science, may attend 
during his second and third years the Courses on Organic 
Chemistry, and courses on the Coal Tar Colours and on 
Dyeing and Printing. 

Part of the Laboratory pradice in the second and third 
years will consist in the examination and analysis of raw 
materials, produds from chemical works, &c., in connedion 
with the special courses of ledures on Applied Chemistry. 
In the Chemistry and Physical laboratories the pradical 
work in the second year will be arranged in accordance 
with the branch of Chemistry seleded by the candidate. 

In the third year the student, if sufficiently advanced, 
will be set to work on some analytical process or problem 
in Applied Chemistry, under the diredion of the teaching 
stafif. 

UNIVERSITY COLLEGE, NOTTINGHAM. 

Departments op Chemistry and Metallurgy, 

AND OF Agriculture. 

Professor of Chemistry. — Frank Clowes, D.Sc. Lond., 
F.I.C. 

Demonstrators of Chemistry. — ^J. J. Sudborough, D.Sc, 
Ph.D., F.LC, R. M. Caven, B.Sc, F.I.C, and G. Mel- 
land, B.Sc, A.R.S.M. 

The Classes of the College are open to students of both 
sexes above sixteen years of age. 

The dates of commencement and end of Terms in the 
Session 1895-96 will be as follows : — First Term, October 
7th to December 2xst ; Second Term, January 20th to 
April 2nd ; Third Term, April 20th to July 4th. 

Lecture Courses, — The Chemistry Day Ledures extend 
over three years. In the first year a student enters for 
the course on Non-Metals for the first two terms and for 
Elementary Organic Chemistry in the third term. In his 
second year he takes the course on Metals for the first two 
terms. In his third year he attends a course on Advanced 
Organic Chemistry or Applied Chemistry. Fee for Day 
Ledures and Classes : Non-Metals or Metals 42s. ; 
Organic Chemistry (one term) 21s. ; Advanced Organic 
Chemistry, 21s. per term. 

Demonstrations and Ledures on Analytical Chemistry 
will be given in the day and evening, and should be 
attended b^ all students. 

A Chemical Calculation Class is also held. Fee per 
Term, 5s. 

Students may qualify themselves by attendance at these 
ledures and classes for the Examinations of the Univer- 
sities of London, Cambridge, or Oxford, and for the 
Medical Examinations of the Royal College of Surgeons 
and of the Universities of Cambridge and Edinburgh : 
they may also obtain instrudion in Chemistry for technical 
or other purposes, and can enter for a full Chemical 
Engineering Curriculum. Special attention is given to 
the requirements of candidates for the Associateship of 
the Institute of Chemistry. 

Practical Chemistry. — The chemical laboratory is open 
every day from 10 to 5, except on Saturday, when the 
hours are from zo to z, and on Tuesday and Thursday 
evenings from 7 to 9. Each Student works independently 
of other Students at a course recommended by the Pro- 
fessor. Instrudion is given in general Chemical Manipu-. 
lation, in Qualitative and Quantitative Analysis, and in 
the methods of Original Chemical Investigation and 
Research; Students are also enabled to work out the 
applications of Chemistry to Pharmacy, Dyeing, Agricul- 
ture, Brewing, Iron and Steel, Tanning, and other Manu- 
faduring Processes. Fees for day students: For one 
term, £7 ; for the session, ;£'i8 ; for six hours weekly 40s., 
and 5s. extra for each additional hour per week. For 
evening students, zos. for two hours per week, three 
hours 153., four hours 20s., six hours 30s., per term. 

Courses of Technical Chemistry Lectures are also given 
on Engineering, Dyeing and Bleaching, Brewing, Plumb- 
ing, Bread-making, Gas Manufadure, and on other pro- 
cesses of applied Chemistry. 



122 



Schools of Chemistry. 



t Chbuical Mbwb, 
I Aug. 30, ifc95. 



PharmaciuHcal Stndints can at all times work in the 
Chemical Laborator}', taking work suitable for the pre- 
paration for the Minor Examinations. Special leAures 
will also be given in Chemistry and Materia Medica. 

Government Lectures and Classes, — Evening Ledures 
and Laboratory instruAion will be given by the Demon- 
rators of Chemistry to Students who intend to present 
themselves for Examination by the Government Science 
and Art Department in May next. Inorganic, organic, 
and praAical chemistry, agricultural chemistry, and 
metallurgy will be taught in the elementary, advanced, and 
honours stages, each of which commences at the beginning 
of the College Session in Odober. Fee for each Le^ure 
Course, 58. ; for each Laboratory Course, los. 

An Agricultural Course of instrudion, extending over 
two years, is now organised under the general direAion 
of Mr. M. J. R. Dunstan, M.A., F.R.S.E. It includes 
instrudion in chemistry, botany, agriculture, with pra^ical 
work on experimental fields, dairy work, farriery, land 
surveying, &c. The instrudlion is designed for those who 
intend to become farmers, bailiffs, land agents, or 
colonists, and may be extended to a third year if desired. 
Fee, £'15 per annum for residents in Notts, ;^20 to 
residents in other counties. 

Full information concerning all College Classes is given 
io the College Prospedus, price one penny. 



FIRTH COLLEGE, SHEFFIELD. 

Professor of Chemistry. --V/, Carleton Williams, B.Sc. 
F.C.S. 

Demonstrators and Assistant Lecturers. — G. Young, 
Ph.D., and L. T. O'Shea, B Sc, F.C.S., 

The Session will commence on October ist. 

First Year's Course. — Chemistry of the Non-Metallic 
Elements. Tuesday and Friday from 10 to 11 a.m. Fee, 
£1 128. 6d. 

Second Year's Couri^.— Chemistry of Metals. Monday 
and Thursday from 10 to iz a.m. £2 12s. 6d. 

Third Year's Course. — Organic Chemistry, on Wednes- 
day, from 9 to 10, and Saturday, from 10 to 11. Fee, 
£2 28. Chemical Philosophy, Thursday, ix to 12. Fee, 
£t lis. 6d. 

Short Courses of Ledures are also given by L. T. 
0*Shea on Eledrolytic Analysis, and on the Chemistry of 
Coal Mining. 

A Course of Ledures is arranged for Medical Students, 
with a special class in Qualitative Analysis. 

Laboratory, — Working hours to be arranged between 
Professor and Students. 

Sessional Fees for Day Students :— Six hours per week, 
£5 5s.; Nine, £7; Twelve, £S 8s.; Eighteen, ;f 11 5s.: 
Twenty- four, ;f 14 ; Thirty-two, £ij. 

Day Students ma^ not enter for less than six hours a 
week. Students joming the Laboratory at Christmas 
will be charged two-thirds and at Easter one-third of 
the Fees for the whole Session. 

Fees for short periods (working thirty-two hours per 
week) : — For one month, £^ 3s.; two months, £$ 58. 

An arrangement has been entered into with the Science 
and Art Department, South Kensington, which will enable 
^ience Teachers to work in the Chemical Laboratory for 
three, six, or twelve hours a week on payment of one- 
quarter of the usual fee, the Department being willing 
to pay the remainder under certain conditions, of which 
full information may be obtained on application to the 
Registrar. 

Students who have worked for three sessions in the 
Chemical Laboratory are eligible for eledion to a scholar- 
ship value ;f 150 for two years. 

Evening Classes. — Ledures, Wednesday, 8 to 9. Labo- 
ratory instruction, Wednesday, 6 to 9, and another series 
to be arranged if desired. Sessional Fee, one evening per 
week, £t los. ; two, 50s. ; or Ledure Class and Labora- 
tory, on Wednesday evening, £1 zos. 



UNIVERSITY COLLEGE, DUNDEE. 

Professor of Chemistry, ^Jtimtt Walker, Ph.D., D.Sc. 

Assistant Lecturers. — F. J. Hambly, F.I.C., and J. R. 
Appleyard, F.C.S. 

Lecture Assistant and Laboratory Steward, — J. Foggie, 
F.C.S. 

The Winter Session begins on Odober Z5th, and ends 
on March 2i8t. The Summer Session extends from May 
to July. 

The First Year*s Lecture Course on Systematic Che- 
mistry is given daily during the Winter Session, and 
embraces the Elements of Inorganic and of Organic 
Chemistry. 

Advanced Courses, of about fifty ledures each, will be 
given during the year as follows: — 

Organic Chemistry; Inorganic Chemistry, including 
the more important technological applications; Theo- 
retical and Physical Chemistry ; Bleaching and Dyeing, 
including the Chemistry of the Textile Fibres. 

Pradical Instrudion in all of the above branches will 
be given in the Laboratories and Dye-house. To supple- 
ment the Pradlical work of First Year*s Laboratory 
Students a short course of LeAures on Analytical 
Chemistry will be offered. Special facilities are afforded 
to Research Students. 

The Le&ures and Laboratory PraAice in Chemistry 
are recognised by the Medical Colleges of London and 
Edinburgh, as well as by the University of Edinburgh, 
for degrees in Science and Medicine. The Courses are 
suitable for the degrees of the University of London and 
for the Civil Service appointments, and will also satisfy 
the requirements of Students in Pharmacy, and of 
Students who intend to become candidates for the 
Associateship of the Institute of Chemistrye as far as 
qualification in Chemistry is concerned. 

UNIVERSITY OF EDINBURGH. 
Department of Chbmistry. 

Professor.^Alex. Crum Brown, M.D., D.Sc, F.R.S., 
Pres. C.S. 

Lecturers.—L, Dobbin, Ph.D., and H. Marshall, D.Sc. 

Assistants.'-V/. W. Taylor, M.A., and A. F. Watson, 
B.Sc. 

The working terms are — Winter Session, from middle 
of Odlober to middle of March ; Summer Session, from 
beginning of May to end of July. 

Lecture Courses. — During the Winter Session a General 
Course of Chemistry for medical and science students it 
given by the Professor. The class meets daily ; fee £^ 48. 
An Advanced Course of twenty- five ledures is also given 
in the Winter Session ; fee, £2 as. A class on Organic 
Chemistry is held in summer ; fee, £2 2S. There is also 
a class on Chemical Theory, by Dr. Dobbin ; fee £1 if. : 
and a class on Crystallography, by Dr. Marshall ; fee, 

£2 2S. 

In addition to the above, Ledlure Courses are given by 
the Assistants on some particular branch of Organic 
and Inorganic Chemistry. These Ledlures are free to 
Laboratory Students. 

Tutorial classes are held in connexion with the 
General Course. 

Laboratories.—VmCticsLl classes for Medical Students 
meet daily during the latter part of the Winter Session 
and in the Summer Session. (Fee, ^3 3s.) The labora- 
tories for analytical and advanced pradical work are 
open daily from 10 till 4. (Fees : Whole Day — Winter 
Session, ;fio los., Odt.-Dec, Jan.-March; or Summer 
Session, £$ 5s. Half Day — Winter Session, £6 6s., Ofl.- 
Dec, Jan.-March ; or Summer Session, £3 3s. Preference 
wili be given to students in the above order. Students 
who are not Matriculated may attend the Chemical 
Laboratory on payment of the entrance fee of 5s. in aidi- 
tion to the Laboratory fees. Full Courses of instrudion 
are given in Analytical, Pradical Organic and Inorganic 
Chemistry. Facilities are afforded to advanced students 
who desire to undertake chemical investigations. 



CHByiCALMlWB.) 

Sept. 6» 1893. J 



Schools of Chemistry. 



m 



Various prizes i&nd scholarships are attached to the 
laboratory and general class. 

Graduation. — Two Degrees in Pure Science are con- 
ferred, viz., Bachelor of Science (B.Sc.) and Dodor of 
Science (D.Sc). 

Candidates for Degrees in Science, if not graduates (by 
examination) in Arts in one of the Universities of the 
United Kingdom or in a Colonial or Foreign University 
recognised for the purpose by the University Court, must 
pass a preliminary examination in (x) English ; (2) Latin, 
Greek, French, or German ; (3) Mathematics ; (4) One of 
the languages Latin, Greek, French, German, Italian, not 
already taken under (2), or Dynamics. In the case of a 
student whose native language is other than European, \ 
the Senatus may, at the Preliminary Examination, accept 
such language as a substitute for a modern European 
language. The Senatus may also in such a case accept 
as an alternative to Latin or Greek any other classical 
languages, such as Sanscrit or Arabic. 

The First B.Sc. Examination embraces Mathematics, 
or Biology (i.#.. Zoology and Botany), Natural Philosophy, 
and Chemistry. The Second B. Sc. Examination includes 
any three or more of the following subjedls: — i. Mathe- 
matics. 2. Natural Philosophy. 3. Astronomy. 4. 
Chemistry. 5. Human Anatomy, including Anthropology. 
6. Physiology. 7. Geology, including Mineralogy. 8. 
Zoology, including Comparative Anatomy. 9. Botany, 
including Vegetable Physiology. Chemistry in this 
examination includes Inorganic Chemistry, Organic Che- 
mistry, Relation between Chemical and Physical Proper- 
ties, Complex Qualitative Analysis (pradlical), Simple 
Quantitative Determinations (pradical), and Gas Analysis 
(pradical). 

A candidate for the D.Sc. Degree must submit a thesis 
00 original work done by him. The Thesis must be 
approved before the candidate is allowed to proceed to 
Examination. The candidate in Chemistry may be re- 
quired to pass a searching examination in one of the 
following branches :— (i) The Chemistry and Chemical 
Technology of Inorganic Bodies, including Metallurgy ; 
(2) Orjganic Chemistry ; and to show a thorough praiflical 
acquaintance with chemical analysis in all its branches, 
and with the preparation of pure substances. 

HERIOT-WATT COLLEGE, EDINBURGH. 

Pro/mor.—John Gibson, Ph.D., F.R.S.E. 

Assistant Professor, — ^John E. Mackenzie, Ph.D., B.Sc. 

Demonstrators. — Andrew F. King and James B. Shand. 

The Session begins October 8th, 1895. 

The curriculum of this College comprises both Day 
and Evening Classes, each department providing the 
higher general and technical education. 

The Ledure Course to day students in Chemistry is 
mainly devoted to Inorganic Chemistry. In the Labora- 
tory course each student is required to prepare and study 
the properties of the principal elementary and compound 
gases ; to perform the more important experiments shown 
by the Professor in the Ledure Room ; to make himself 
thoroughly acquainted with the preparation and purifica- 
tion of a number of salts. After a careful study of the 
readions of the principal metals and acids, he passes on 
^o a full course of systematic qualitative analysis, 
and may then, if attending a second year, take up an ex- 
tensive course of quantitative analysis (gravimetric, 
volumetric, and eledrolytic), ultimately making a 
speciality of any branch of the subjeA which may be 
most necessary for his future work. Great attention has 
been paid to the thorough equipment of the Advanced 
Laboratories, and special facilities are given to advanced 
students who may wish to engage in any class of Re- 
search (Inorganic or Organic) whether of a purely che- 
mical or of a technical nature. 

The teaching in the Evening Classes is based on the 
Syllabus of the Science and Art Department, and in- 
cludes Elementarvi Advanced, and Honours Courses in 
Jheoretical and Pra^cal Inorganic and Organic Che- 
mistry. 



GLASGOW AND WEST OF SCOTLAND 
TECHNICAL COLLEGE. 

Professor of Chemistry, — G.G. Henderson, D.Sc, M.A. 

Professor of Technical Chemistry, — E. J. Mills, D.Sc, 
F.R.S. 

Assistants.-^], Hcndrick, B.Sc, F.I.C., A. R. Ewing, 
Ph.D., and T. Gray, B.Sc, F.C.S. 

Professor of Metallurgy.— \, Humboldt Sexton, F.C.S., 
F.R.S.E. 

The main objeds of this College are to afford a 
suitable education to those who wish to qualify themselves 
for following an industrial profession or trade, and to 
train teachers for technical schools. It was founded by 
an Order in Council, dated 26th November, z886, 
according to a scheme framed by the Commissioners 
appointed under the provisions of the Educational 
Endowments (Scotland) Ad, whereby Anderson's College* 
the Young Chair of Technical Chemistry in connexion 
with Anderson's College, the College of Science and Arts, 
Allan's Glen's Institution, and the Atkinson Institution 
were placed under the management of one governing 
body. 

The Diploma of the College is awarded to Day Students 
who have attended prescribed courses of instrudion and 
passed the necessary examinations. The ordinary courses 
extend over three years, but arrangements are made for 
advanced students continuing their studies in special 
departments. 

Complete courses of instruAion in Metallurgy and 
Mining will be given in both Day and Evening Classes. 

Copies of the Calendar for 1893*94 maybe had from Mr. 
John Young, B.Sc, the Secretary, 38, Bath Street, 
Glasgow, price by post, is. 4d. 

UNIVERSITY OF ST. ANDREWS. 
United Colleob of St. Leonard and St. Salvator, 

Professor of Chemistry, --T, Purdie, B.Sc, Ph.D., 
F.R.S. 

The Session begins on OAober loth. A Competitive 
Examination, open to intending Students of Arts or 
Science, for about furty-five Entrance Bursaries, ranging in 
value from £40 to £10 each per annum, will be held 
in the beginning of Odtober. About thirty of these 
Bursaries, are restricted to Men and thirteen to Women, 
seven of the latter being intended for women who at the 
conclusion of their Arts or Science Course will proceed 
to Medicine. Two are open to students of either sex. 
Two Scholarships of ;£"ioo each, tenable for one year, will 
be open for competition to Graduates of Science at the 
close of Session 1895-96. A Hall of Residence is 
provided for Women Students. Two Degrees in Science 
are conferred by the University of St. Andrews, viz., 
Bachelor of Science (B.Sc) and Doctor of Science (D.Sc), 
and Chemistry is also included in the curriculum for the 
M.A. Degree ; the regulations will be found in the 
•• University Calendar." 

Lecture Courses, 

Two distind Courses of Ledures are given, each com* 
prising at least one hundred meetings of the class. 

First Year's Course, — This Class meets at 11 o'clock 
on five days in the week. The introdudory ledures 
treat of the Nature of Chemical Adion, the Classification 
of Substances into Elements and Compounds, the Phe- 
nomena of Oxidation, and the Composition of Air and 
Water. The Laws of Chemical Combination and the 
Atomic Theory are next discussed, after which the more 
commonly occurring elements and inorganic compounds 
are described systematically. Elementary Organic Che- 
mistry is also included in the Course. 

The chemistry of manufadures is referred to only 
cursorily ; special attention, on the other hand, ts 
given to those parts of the science which are of general 
educational value, and as much of the theory of chemistry 
is introduced as is compatible with elementary treat- 
ment. The Ledures are supplemented by a short Course 



124 



Schools 0) Chemistry. 



' CBsmcAL Nmrt, 
t Sept. 6. 1695. 



of Laboratory Pra^ice, intended to illustrate the principles 
of the science. ! 

These courses of instniAion are intended to meet the 
requirements of the Arts' Curriculum ; also of candidates ' 
for the First B.Sc. Examination, and of students of 1 
medicine, so far as Theoretical Chemistry is concerned. 

Second Yearns Coursi. — The first part of the Course 
is devoted to Organic Chemistry, and the second part 
treats of the General Principles and Theory of Chemistry, 
and of more advanced Inorganic Chemistry, the instruc- 
tion in general being such as is required for the Second 
B.Sc. Examination. 

Certificates are awarded on the results of examinations, 
and the •* Forrester Prixe " of about £10 is awarded to 
the best Student of the year. 

Fee for the Session, for each Course, £$ 3s. 
Practical Chemistry, 

The Laboratory is open daily from 9 a.m. to 4 
p.m., except on Saturdays, when it is closed at z 
p.m. The work pursued in the Laboratory comprises :— 
(i) The performance of experiments illustrative of the 
Principles of Inorganic and Organic Chemistry ; (2) 
Qualitative and Quantitative Analysis ; (3) Original 
Investigation. Each student pursues an independent 
course of study under the supervision of the Professor or 
Demonstrator, the nature of the work varying with the 
proficiency of the student and the particular objed he 
may have in view. Suitable courses of instruction in 
Pradical Chemistry are provided for candidates for 
the First and Second B.Sc. Examinations, and for 
Students of Medicine. 

The fees for Pradical Chemistry vary according to the 
number of hours taken weekly. A certain number of 
working places in the Laboratory will be available with- 
out fee for students who are capable of undertaking 
original investigation. 

QUEEN'S COLLEGE, BELFAST. 

Professor.— E, A. Letts, Ph.D., D.Sc. F.R.S.E., &c. 

I. — Chemistry, — The ledures are delivered at 3 p.m., 
on the first five days of each week until the beginning 
of April, and on three days of each week after May ist, 
at 2 p.m. The course is divided into three parts : — (i) 
Chemical Philosophy; (2) Inorganic Chemistry; (3} 
Organic Chemistry. 

II. — Advanced and Organic Chemistry, — Ledures on 
these subjeds are given during the first or second terms, 
or from May ist until the middle of July, as may suit the 
convenience of the class. Fee, £1, 

III. — Practical Chemistry, — In this course the Students 
are instruded in the general methods of conduding 
Chemical Analyses. Fee, £'3. 

IV. — Laboratory Pupils, — The Chemical Laboratories 
is open from November until the end of March, and from 
May zst until the third week of July, on the first five 
days of the week, from 10 a.m. until 4 p.m. Students are 
admitted as working pupils on payment of a fee of £5 
for the first period, or of £2 zos. for the second period (or 
for a single term). 

Scholarships, — In addition to various Scholarships 
awarded in the Faculties of Arts and Medicine in which 
Chemistry forms a part of the examination, there are other 
valuable Scholarships awarded specially in connedion 
with the schools of Chemistry and Ph3'sics. 

QUEEN'S COLLEGE, CORK. 

Professor, — Augustus E. Dixon, M.D. 

Assistant,— D, J. O'Mahony, F.C.S. 

The College Session begins on Odober zyth, zSgs, and 
ends on June 8th, Z895. The classes are open to male 
and female students. 

Systematic Chemistry, ^1) General course of Inorganic 
Chemistry, Elementary Organic Chemistry, and Chemical 
Philosophy. — Fee for each Sessional Course, £2, Each 
subsequent Course,j£'z. (2) Advanced Organic Cbemis- 
try, and Chemical Philosophy. 



Practical Chemistry,— (i) The General Course of Pradi- 
cal Chemistry, consisting of about forty Ledores of two 
hours each, begins on January 7th, Z895.— Fee ^^^ ^^^ 
Sessional Course, £^, (2) A Course for Pharmaceuttcal 
Students. (3) Special Courses. 

The Chemical Laboratory is open daily from zo to 4 
o'clock (except during class hours and on Saturdays) 
under the Superintendence of the Professor, to Students 
entering for special courses of qualitative and quantitative 
analysis ; organic chemistry ; or for the purpose of original 
investigation. 

QUEEN'S COLLEGE, GALWAY. 

Professor,— AUrtd Senier, Ph.D., M.D., F.I.C. 

Dtmonstrator,—k, J. Walker. 

The College Session is divided into three terms. The 
First Term extends from Odober Z5 to December ai, the 
Second Term from January 6 to March a8, and the Third 
Term from April Z3 to June Z3. 

Chemistry is studied by attendance at Ledures, by 
work in the Laboratories, and by the use of the College 
Library. The Courses in the several faculties mre 
arranged with a view to the requirements of the Royal 
University of Ireland, but are adapted also to those of 
other Universities and licensing bodies. 

Lecture Courses, — z. First year's Course, Arts and 
Engineering, embraces Inorganic and the Elements of 
General Chemistry. 2. First year's Course, Medicine, 
includes Inorganic and Elementary Organic Chemistry. 
3. Third year's Course, Arts, is devoted to Advanced 
Ore:anic Chemistry. 

Laboratory Courses. — z. Second year's Course, Arts 
and Engineering, consists of Exercises in Inorganic 
Qualitative Analysis. 2, Second year's Course, Medicine, 
includes Inorganic and Elementary Organic Qualitative 
Analysis and the Chemical Examination of Urine. 
3. Third year's Course, Arts, embraces Quantitative 
Analysis and other experiments to suit the requirements 
of individual Students. 4. The Laboratories are also 
open to Students for work in other branches of Che- 
mistry. 

For Fees and other particulars apply to the Registrar, 
from whom the Calendar, published in December, and 
the Extrads from Calendar, published in advance in July, 
may be obtained. 

ROYAL COLLEGE OF SCIENCE FOR IRELAND, 

Stephen's Green, Dublin. 

(Science and Art Department), 

Professor of Chemistry,— Vf. N. Hartley, F.R.S. 

Assistant Chemist,— HMg\i Ramage, F.I.C, Associate 
of the Royal College of Science, Dublin. 

Demonstrator of Chemistry and Assaying,— iy%cmnx\. 

The Session commences on Monday, Odober ist, 1894, 
and ends on June 21st, 1895. 

The Royal College of Science for Ireland supplies, as 
far as pradicable, a complete course of instrudion in 
Science applicable to the Industrial Arts, and is intended 
also to aid in the instrudion of teachers for the local 
Schools of Science. 

Diplomas are awarded in the Faculties of Mining, 
Engineering, and Manufadures. The Diploma of Asso- 
ciate of the Royal College of Science in the Faculty of 
Manufadures is recognised by the Council of the Insti* 
tute of Chemistry of Great Britain and Ireland as 
qualifying candidates for admission to the pradical ex* 
amiuations of the Institute. 

The instrudion in Chemical Science includes (z) General 
Chemistry ; (2) Advanced Chemistry, including Chemical 
Manufadures and Metallurgy ; (3) Analytical and Experi- 
mental Chemistry ; (4) Instructions in Chemical Research. 

Fees payable by Associate Students in the Faculty of 
Manufadures :— For the entire Course— first vear, £z9 ; 
second year, ^25; third year, ;(Z2. y 

Fees payable by Non- Associates :— ;(a foc^jpiaiieparale 



Cbrmical Niwb, I 
Stpt. 6, 1895. I 



Schools oj Chemistry. 



"5 



Course of Le^ures. For Analytical Chemistry and 
Research— ;f2 for a special course of one month ; £5 for 
three months; £g for six months; ;£'i2 for the entire 
session. For Assaying— ;f 5 for three months ; £^ for six 
months £'ia for the entire session. 

Note. — Important changes have been made in the 
Curriculum by which the First Year's Course of study 
has been simplified. Full particulars are contained in the 
Direaory of the College, which may be had on application 
to the Secretary. 

The following are supplementary courses of instrudion 
arranged for those who are attending a Course of 
Ledures : — 

(i) Laboratory Instrudion in the Theory of Chemistry. 

(2) An Analytical Course for Students in Engineering. 

(3) A Course of Pradical Chemistry for Medical Students. 

(4) The Analysis of Water, Air, Food, and Drugs, in 
tended for the instrudion of Public Analysts and Medical 
Officers of Health. (5) Assaying. 

There are four Royal Scholarships of the value of £$0 
each yearly, with Free Education, including Laboratory 
Instrudion, tenable for two years; two become vacant 
each year ; they are awarded on the results of their 
examinations to Associate Students, not being Royal 
Exhibitioners, who have been a year in the College. 
There are also nine Royal Exhibitions attached to the 
College, of the yearly value of £$0 each, with Free 
Education, including Laboratory Instrudion, tenable for 
three years; three become vacant each year, and are 
competed for at the May Examinations of the Depart- 
ment of Science and Art. 



CHEMICAL LECTURES, CLASSES, AND 
LABORATORY_[NSTRUCTION. 

City and Guilds of London Institute for the 
Advancement op Technical Education.— The opera- 
tions of the City and Guilds of London Institute are 
divided broadly into four branches : the educational work 
of three London Colleges, and of the Technological 
Examinations. Programmes of the London Colleges 
may be had on application to the Head Office of the 
Institute, Gresham College, Basinghall Street, London, 
E.C.. or from the respedive Colleges. The Technolo- 
gical Examinations (Examinations Department, Exhibition 
Road, S.W.), are conduded once every year at various 
centres throughout the kingdom. Programme, with 
Syllabus of Subjeds, &c., may be obtained of Messrs. 
Whittaker and Co., Paternoster Square, London, or 
through any bookseller, price lod., net. — City and 
Guilds Technical ColUgf, Exhibition Road, — Professor 
of Chemistry, H. E. Armstrong, Ph.D., F.R.S. The objed 
of this Institution is to give to London a College for the 
higher technical education, in which advanced instrudion 
shall be provided in those kinds of knowledge which bear 
upon the different branches of industry, whether Manu- 
ladures or Arts. The main purpose of the instrudion 
given is to point out the application of different 
branches of science to various manufaduring industries. 
In order that this instrudion may be efficiently carried 
out, the Institution, in addition to the ledure theatres 
and class rooms, is fitted with laboratories, drawing 
offices, and workshops ; and opportunities are afforded 
for the prosecution of original research, with the objed of 
the more thorough training of the students, and for the 
elucidation of the theory of industrial processes. The 
courses of instrudion are arranged to suit the require- 
ments of— I. Persons who are training to become 
Technical Teachers ; 2. Persons who are preparing to 
enter Engineers* or Architeds' offices, or Manufaduring 
works ; 3. Persons who desire to acquaint themselves with 
the scientific principles underlying the particular branch 
of industry in which they are engaged. The Matriculation 
Examinations will begin on Tuesday, Sept. zjth, and 



the Winter Session opens on Tuesday, October ist. 
City and Guilds Technical College, Finsbury. — Professor 
of Chemistry, Raphael Meldola, F.R.S. The operations 
of the Technical College, Finsbury, are divided into two 
distinct portions : Day Classes for those who are 
able to devote one, two, or three years to 
systematic technical education ; Evening Classes for 
those who are engaged in industrial or commercial 
occupations in the daytime And who desire to receive 
supplementary instruction in the application of Science 
and of Art to the trades and manufactures in which they 
are concerned or employed. Each Professor is assisted 
by Demonstrators. Besides these there are Lecturers 
and Teachers in special subjects. An examination for 
the admission of Students will be held at the College 
at 10 o'clock on Tuesday, September 17th, 1895. 
South London Technical Art ScAoo/.— Classes in Model- 
ling, Design, Wood Engraving, Drawing and Painting, 
House Decoration, Machine Dr4wing and Design, 
Plaster-work, &c. 

Addey*s Science and Art School, Church Street, 
Deptford.— Head Master, William Ping, F.C.S.— Day 
and Evening Classes in Theoretical and Pradical Che- 
mistry, Physics, &c. The Classes are approved by the 
County Council. 

BiKKBBCK Literary and Scientific Institution: 
Bream's Buildings, Chancery Lane. — Chemistry , 
Courses will be conduded, commencing September 24th, 
adapted for the Elementary, Advanced, and Honours 
Examinations of the Science and Art Department, and for 
the Matriculation, B.Sc, and M.B. Degrees of the London 
University. /nor^arair Chemistry: Mr. J. Woodward, B.A., 
B.Sc. Lectures — Elementary, Tuesdays, 8.15 p.m.; 
Advanced, Thursdays, 6.15; Practical, Tuesdays, 6—8 
p.m.; Thursdays, 7.30— 9.30 p.m. Organic Chemistry : 
Mr. F. Gossling, B.Sc. Lectures — Elementary, Wednes- 
days, 6 to 7 p.m. ; Practical, Wednesdays, 7 to 9 p.m. 

The Central School of Chemistry and Pharmacy, 
173, Marylebone Road, London. — Dr. A. B. Griffiths, 
F.R.S.E., F.C.S., &c.. and Mr. Lionel Cooper, F.C.S. 
Lectures are given on Chemistry, Physics, Botany, 
Materia Medica, Pharmacy, &c. Laboratory Instruction. 

South London School op Pharmacy, Lim., 325, Ken- 
nington Road, S.E. — Ledures on Chemistry and Physics, 
by Dr. John Muter, F.R.S.E., F.I.C., Daily, at 9 a.m. 
(Organic) and 10 a.m. (Inorganic). Lredures on Botany 
daily at 12 noon, and at 2 p.m. on Materia Medica and 
Pharmacy, by Mr. Dodd, F.C.S. The Laboratories for 
Qualitative and Quantitative Analysis open daily from 9 
till 5, under the diredion of Mr. de Koningh, F.I.C., 
F.C.S. The Students' Laboratory of this Institution is 
specially designed to accommodate 40 Students. The 
Technical Laboratory is open daily from 9 till 5, and is 
fully fitted with all apparatus for teaching the manufadure 
of drugs and chemicals. Periodical Examinations of the 
Students are held by Visiting Examiners appointed by 
the Council of Education, and Medals and Certificates 
are awarded on the results thereof. Fees for the first 
three months 12 guineas ; afterwards 2i guineas per month 
respedively, inclusive of all departments. 

The Goldsmiths* Institute, New Cross, S.E,<— Head 
of the Chemistry Department, Mr. A. G. Bloxam, F.I.C. ; 
Assistants, Mr. H. C. L. Bloxam and Mr. Percy Tarver, 
A.R.C.S. Ledures and Pradical Classes in General 
Chemistry, also in Chemistry applied to Leather Manu- 
fadure and Gas Manufadure, are held in the evenings 
from 7.30 to 10.0, and are open to bo'.h sexes. 

People's Palace, Mile End Road, E. (Draper's Com- 
pany's Institute).— Professor, J. T. Hewitt, M.A , D.Sc, 
Ph.D.; Assistant, Mr. F. G. Pope. The classes are 
open to both sexes without limit of age. Evening classes 
in Theoretical and Pradical Chemistry. The Session 
commences on Monday, September 23rd. A course for 
the London University B.Sc. Degree, including Honours, 



126 



Schools Of Chemistry. 



I ClIftMICAL llBWt« 

I Sept. 6« 1895. 



is now offered, and the Chemical Laboratory has been 
newly equipped. Every facility is offered to Students 
desiring to undertake Research work. 

PoLYTBCHNic Institutb, 309, Regent Street, London, 
W.— Mr. R. A. Ward and Assistants.— Evening Classes 
in Theoretical and Praaical Chemistry, &c.. The Classes 
are open to both sexes. The next term commences on 
October ist, 1894. 

Univbrsity Tutorial Collbgb, 32. Red Lion Square, 
Holbom, W.C. (Science Department of the Univ. Corr. 
Coll.). — The large Chemical, Biological, and Physical 
laboratories have been found admirably suited to their 
purpose, and the proportion of passes in the London 
University Science Lists has increased rapidly. Students 
may work either for long or short periods. 

Westminster Collbob of Chemistry and Pharmacy, 
Trinity Square, Borough, S.E. — Messrs. Wills and 
Wootton. Day and Evening Classes. 

Bristol Medical School.— Mr. T. Coomber, F.C.S. 

The Clifton Laboratory, Berkeley Square, Bristol.— 
Students are received either as Piivate Pupils or Members 
of a Class. Instruction is given to those requiring to use 
science or scientific methods in Commercial and Indus- 
trial pursuits, or in preparing for Examinations. Every 
effort is made to produce thorough chemists rather than 
successful examinees. 

Leeds School of Scibncx and Tbchnolooy, 
(Mechanics' Institution, Leeds).— There is a three years* 
course of ledures in Inorganic Chemistry, and a two 
years' course in Organic Chemistry and Metallurgy. 

Institute op Chemical Technology, Hackins Hey, 
Liverpool (A. Norman Tate and Co.).— Principal, Mr. 
F. H. Tate, F.C.S. The course of instrudion is intended 
more especially for students who wish to gain a know- 
ledge of chemistry and the allied sciences in their relation 
to industrial and commercial pursuits, and embraces a 
thorough preliminary course of theoretical chemistry and 
pradical laboratory work, followed by instrudlion in 
chemical technology fitted to the requirements of each 
pupil. In addition to these chemical studies, students 
who desire it can enter upon a special course calculated 
to afford them knowledge useful in the eredion and 
arrangement of manufactories and plant, and construc- 
tion of apparatus. 

The Municipal Technical School, Princess Street, 
Manchester.— Theoretical and Pradical Chemistry, Mr. 
E. Knecht, Ph.D., F.I.C., and Mr. J. Grant, F.I.C.. 
F.C.S. Metallurgy, Mr. E. L. Rhead. At this important 
Municipal School, with an attendance of upwards of 3000 
Students, there are organised Day Courses in Pure 
Chemistry, with applications to Dyeing, Bleaching, and 
Printing. In addition there are Evening Courses, not 
only in Pure Chemistry, but in Metallurgy, Iron and 
Steel Manufadure. Brewing, Oils, Colours and Varnishes, 
Oils and Fats, Soap Manufacture, Bleaching, Dyeing, 
and Printing, Coal Tar Produds, Paper Manufaaure, 
and Photography. The complete Syllabus (4d., by post 
6d.) may be obtained on application to Mr. J. H. Reynolds, 
Diredor and Secretary, Princess Street, Manchester. 

Higher Grade School, Patricropt.— Science and 
Art Day and Evening School, and Institute for Women. 
Demonstrator in Chemistry, Mr. R. J. B. Sanderson. 

Technical Institute, Birley Street, Beswick,— 
Demonstrator in Chemistry, Mr. R. J. B. Sanderson. 

Sheffield Borough Analysts* Laboratory, i, 
Surrey Street. — Mr. A. H. Allen, F.C.S. Day and 
Evening Classes. 

Stockport Technical School. — Department of 
Chemistry and Dyeing.— Principal : Mr. R. J. Brown, 
M.Sc. A syllabus with full particulars of the courses of 
instrudion, hours, fees, &c., is obtainable on application. 



Technical Institutb, Swansea. — Classes in 
Theoretical and Pradictl Organic and Inorganic Chemis- 
try, Metallurgy, Hygiene, Mathematics, &c., from Octo* 
ber to May. Principal, W. Morgan, Ph.D., F.I.C. 

Aberdeen University.— Prof. Japp, 

School of Medicine, Edinburgh. — Dr. S. Macadam, 
Mr. King, Mr. I. Macadam. Mr. Patersoo, and Drt. 
Aitken and Readman. 

SuROEON*s Hall, Nicolson Street, Edinburgh. — Mr. 
Ivison Macadam. Laboratory work and deroonstrations 
in Agricultural Chemistry. Chemistry Class for Women. 

St. Mungo's College and School of Mboxcinb, 
Edinburgh. — Dr. Marshall. 

City Analyst's Laboratory and Class Room, 138, 
Bath Street, Glasgow.— Messrs. Wallace and Claik. 

Glasgow University.— Prof. J. Ferguson, 

Glasgow Veterinary Colleqb.- Professor Cooke. 

Anderson's College. Glassow.— Mr. J. R. WatMMi. 

Royal College op Surgeons in Irbland, Dublin. — 
Professor of Chemistry and Hygiene: Sir Charles A. 
Cameron, M.D., F.R.C.S.I. InstruAion is given in the 
College Laboratory in General, PraAical, and Analytical 
Chemistry, and in the subjeAs (Physical, Chemical, and 
Microscopical) required for Examinations in Public Health 
and to educate for the position of Public Analyst. 

Dublin, Catholic University. — Dr. Campbell. 



CORRESPONDENCE. 



NEW GROUPING OF THE ELEMENTS. 

To the Ediior of the Chemical News, 
Sir, — I suppose some of your readers, before this letter 
can reach you, will have drawn your attention to the fad 
that the ** New Grouping of the Elementu,** given by 
Thomsen in the current volume of Zeitich,/, Anorganitcke 
Chemiet pp. 190—193, is identical with the one given by 
Carnelley (Chemical News, vol. liii.), and by him 
accredited to Bayley {Phil, Mag,, 5, xiii., p. 26). These 
latter authors divide the third group of Thomsen. 

It seems strange that Thomsen should have overlooke4 
the previous publication of the table. — I am, &c., 

F. P. Vbnablb. 
Department of Chemistry, 

Uoivertity ot North Carolina, 
August 17, 189s. 



The Drug, Chemical, and Allied Trades BxhK 
bition. — This useful Trade Exhibition will be opened at 
the Agricultural Hall, Islington, N., on Tuesday next, 
September loth, and will be continued on the three (oU 
lowing days. Exhibits have been received from roost of 
the leading houses, and should form an interesting and 
varied display. The Manager will forward invitation 
tickets to any gentlemen conneded with the trade who 
desire to attend. The Offices of the Exhibition are at 
4a, Bishopsgate Without, E.C. 

The Manner of the Adtion of Dry Hydrocblorie 
Acid upon Serpentine.— E. A. Schneider. — In this re- 
adion there is a formation of water. A part of the water 
formed escapes with the hydrochloric acid ; another por* 
tion is retained by the residual silicate. This residue, on 
treatment with dry hydrogen chloride, behaves like the 
otiginal mol. of serpentine. Water is formed along with 
magnesium chloride. A part of the water formed is re- 
tained by the residual silicate, and there ensues an absorp- 
tion of water. In the experiments of Clarke and Schneider 
the hydrogen chloride used was sufficiently dried to bo 
regarded as "dry,"— ^W#, Anorg. Ckem^ 



CiMyicAi. News, ) 
Sept. 13. 1895. f 



British Association.— The President's Address. 



127 



THE CHEMICAL NEWS. 



Vol. LXXIL, No. iSaS. 



BRITISH ASSOCIATION 

FOR THB 

ADVANCEMENT OF SCIENCE. 

Ipswich, 1895. 

INAUGURAL ADDRESS OP THE PRESIDENT, 
Sir Douglas Galton, K.C.B., D.C.L.» P.R.S. 

My first duty is to convey to yoa, Mr. Mayor, and to the 
inhabitants of Ipiwich, the thanks of the British Associ- 
ation for your hospitable invitation to hold our sixty-fifch 
meeting in your smcient town, and thus to recall the 
agreeable memories of the similar favour which your 
priedecessors conferred on the Association forty-four 
years ago. 

In the next place I feel it my duty to say a few words 
on the great loss which science has recently sustained— 
the death of the Right Hon. Thomas Henry Huxley. It 
is unnecessary for me to enlarge, in the presence of so 
many to whom his personality was known, upon his 
charm in social and domestic life; but upon the debt 
which the Association owes to him for the assistance 
which he rendered in the promotion of science I cannot 
well be silent. Huxley was pre-eminently qualified to 
assist in sweeping away the obstmaion by dogmatic 
anthority, which m the early days of the Association 
lettered progress in certain branches of science. Por, 
whilst he was an eminent leader in biological research, 
bis intelleAual power, his original and intrepid mind, his 
vigorous and masculine English, made him a writer who 
explained the deepest subjed with transparent clearness^ 
And as a speaker his lucid and forcible style was adorned 
with ample and effedive illustration in the ledure«room ; 
and his energy and wealth of argument in a more public 
arena largely helped to win the battle of evolution, and 
to secure for us the right to discuss questions of religion 
and science without fear and without favour. 

It may, I think, interest you to learn that Huxley first 
made the acquaintance of Tyndall at the meeting of the 
Association held in this town in 185 1. 

About forty-six years ago I first began to attend the 
meetings of the British Association, and I was eleded 
one of your general secretaries about twenty-five 
years ago. 

It is not unfitting, therefore, that I should recall to 
your minds the conditions under which science was pur- 
sued at the formation of the Association, as well as the 
very remarkable position which the Association has occu- 
pied in relation to science in this country. 

Between the end of the sixteenth century and the early 
part of the present century several societies had been 
created to develop various branches of science. Some of 
these societies were established in London, and others in 
important provincial centres. 

In 183 1, in the absence of railways, communication 
between different parts of the country was slow and diffi- 
cult. Science was therefore localised ; and in addition 
to the universities in England, Scotland, and Ireland, 
the towns of Birmingham, Manchester, Plymouth, and 
York each maintained an important nucleus of scientific 
fcsearch. 

Origin of thb British Association. 

Under these social conditions the British Association 
was founded in September, 183 1. 

Tho general idea of its formation was derived from a 
migratory society which had been previously formed in 



Germany ; but whilst the German society met for the 
special occasion on which it was summoned, and then 
dissolved, the basis of the British Association was 
continuity. 

The objeas of the founders of the British Association 
were enunciated in their earliest rules to be :— 

**To give a stronger impulse and a more systematic 
diredion to scientific inquirjr ; to promote the intercourse 
of those who cultivated saence m different parts of the 
British Empire with one another, and with foreign philo* 
sophers ; to obtain a more general attention to the oojeds 
of science, and a removal of any disadvantages of a 
public kind which impede its progress." 

Thus the British Association for the Advancement of 
Science based its. utility upon the opportunity it afforded 
for combination. 

The first meeting of the Association was held at York 
wiih 353 members. 

As an evidence of the want which the Association sop- 
plied, it may be mentioned that at the second meeting, 
which was held at Oxford, the number of members was 
435. The third meeting, at Cambridge, numbered over 
900 members; and at the meeting in Edinburgh in 1834 
there were present 1298 members. 

At its third meeting, which was held at Cambridge in 
X833, the Association, through the influence it bad 
already acquired, induced the Government to grant a sum 
0/ £500 'or the reduaion of the astronomical observa- 
tions of Baily. And at the same meeting the General 
Committee commenced to appropriate to scientific re- 
search the surplus from the subscriptions of its members. 
The committees on each branch of science were desired 
**to selea definite and important objeas of sciencot 
which they may think most fit to be advanced by an 
application of the funds of the society, either in compen- 
sation for labour or in defraying the expense of apparatus, 
or otherwise, stating their reasons for their seledion, and, 
when they may think proper, designating individuals to 
undertake the desired investigations." 

The several proposals were submitted to the Committee 
of Recommendations, whose approval was necessary be- 
fore they could be passed by the General Committee. 
The regulations then laid down still guide the Associa- 
tion in the distribution of its grants. At that early 
meeting the Association was enabled to apply £600 to 
these objeas. 

• I have always wondered at the foresight of the framers 
of the constitution of the British Association, the most 
remarkable feature of which is the lightness of the tie 
which holds it together. It is not bound by any complex 
central organisation. It consists of a federation of 
Seaions, whose^ youth and energy are yearly renewed by 
a succession of presidents and vice-presidents, whilst in 
each Seaion some continuity of aaion is secured by the 
less movable secretaries. 

The governing body is the General Committee, the 
members of which are seleaed for their scientific work ; 
but their controlling power is tempered by the law that 
all changes of rules, or of constitution, should be sub- 
mitted to, and receive the approval of, the Committee of 
Recommendations. This committee may be described as 
an ideal Second Chamber. It consists of the most expe- 
rienced members of the Association. 

The administration of the Association in the interva 
between annual meetings is carried on by the Council, an 
executive body, whose duty it is to complete the work of 
the annual meeting (a) by the publication of its proceed- 
ings; (6) by giving effea to resolutions passed by the 
General Committee ; {c) it also appoints the Local Com- 
mittee and organises tktptfionnA of each Seaion for the 
next meeting. 

I believe that one of the secrets of the long-continued 
success and vitality of the British Association lies in this 
purely democratic constitution, combined with the com- 
pulsory careful consideration which must be given to 
suggested organic changes. 



128 



British Association. — The President's Address. 



! Chbiiical Nswt, 
\ Sept. 13. 1895. 



The Association is now in the sixty-fifth year of its 
existence. In its origin it invited the philosophical 
societies dispersed throughout Great Britain to unite in a 
co-operative union. 

Within recent years it has endeavoured to consolidate 
that union. 

At the present time almost all important local scien- 
tific societies scattered throughout the country, some 
sixty- six in number, are in correspondence with the 
Association, Their delegates hold annual conferences at 
our meetings. The Association has thus extended the 
sphere of its adion : it places the members of the local 
societies engaged in scientific work in relation with each 
other, and bnngs them into co-operation with members 
of the Association and with others engaged in original 
investigations, and the papers which the individual 
societies publish annually are catalogued in our Report. 
Thus by degrees a national catalogue will be formed of 
the scientific work of these societies. 

The Association has, moreover, shown that its scope 
is coterminous with the British Empire by holding one 
of its annual meetings at Montreal, and we are likely 
toon to hold a meeting in Toronto. 

Condition of certain Sciences at the formation 
OF the British Association. 

The Association, at its first meeting, began its work 
by initiating a series of reports upon the then condition 
of the several sciences. 

A rapid glance at some of these reports will not only 
show the enormous strides which have been made since 
J831 in the investigation of fadls to elucidate the laws of 
Nature, but it may afford a slight insight into the impe- 
diments offered to the progress of investigation by the 
mental condition of the community, which had been for 
to long satisfied to accept assumptions without under- 
going the labour of testing their truth by ascertaining the 
real faas. This habit of mind may be illustrated by two 
instances seleAed from the early reports made to the 
Association. The first is afforded by the report made in 
1832, by Mr. Lubbock, on " Tides.»» 

This was a subjed necessarily of importance to 
England at a dominant power at sea. But in England 
records of the tides had only recently been commenced 
at the dockyards of Woolwich, Sheerness, Portsmouth, 
and Plymouth, on the request of the Royal Society, and 
no information had been coUeded upon the tides on the 
coasts of Scotland and Ireland. 

The British Associaton may feel pride in the fad that 
within three years of its inception, via., by 1834, it had 
induced the Corporation of Liverpool to establish two 
tide gauges, and the Government to undertake tidal ob- 
tervations at 500 stations on the coasts of Britain. 

Another cognate instance is exemplified by a paper 
read at the second meeting, in 1832, upon the State of 
Naval Architedure in Great Britain. The author con- 
trasts the extreme perfedion of the carpentry of the 
internal fittings of the vessels with the remarkable 
deficiency of mathematical theory in the adjustment of 
the external form of vessels, and suggests the benefit of 
the application of refined analysis to the various pradical 
problems which ought to interest shipbuilders— problems 
of capacity, of displacement, of stowage, of velocity, of 
pitching and rolling, of masting, of the effeds of sails, 
and of the resistance of fluids ; and, moreover, suggests 
that large scale experiments should be made by Govern- 
ment, to afford the necessary data for calculation. 

Indeed, when we consider how completely the whole 
habit of mind of the populations of the Western world 
has been changed, since the beginning of the century, 
from willing acceptance of authority as a rule of life to a 
universal spirit of inquiry and experimental investigation, 
it it not probable that this rapid change has arisen from 
society having been stirred to its foundations by the causes 
and consequences of the French Revolution ? 

One of the earliest pradical results of this awakening 



in France was the convidion that the basis of scientific 
research lay in the accuracy of the standards by which 
observations could be compared ; and the following prin- 
ciples were laid down as a basis for their measurements 
of length, weight, and capacity : viz. (i) that the unit of 
linear measure applied to matter in its three forms of 
extension, viz., length, breadth, and thickness, should be 
the standard of measures of length, surface, and solidity ; 
(2) that the cubic contents of the linear measure in deci- 
metres of pure water at the temperature of its greatest 
density should furnish at once the standard weight and 
the measure of capacity.* The metric system did not 
come into full operation in France till 1840, and it is 
now adopted by all countries on the continent of Europe 
except Russia. 

The standards of length which were accessible in 
Great Britain at the formation of the Association were 
the Parliamentary standard yard lodged in the Houses of 
Parliament (which was destroyed in 1834 in the fire which 
burned the Houses of Parliament) ; the Royal Astrono- 
mical Society's standard; and the zo-foot bar of the 
Ordnance Survey. 

The first two were assumed to afford exad measure- 
ments at a given temperature. The Ordnance bar wat 
formed of two bars on the principle of a compensating 
pendulum, and afforded measurements independent of 
temperature. Standard bars were also disseminated 
throughout the country, in possession of the corporations 
of various towns. 

The British Association early recognised the importance 
of uniformity in the record of scientific fads, as well at 
the necessity for an easy method of comparing standards 
and for verifying difftsrences between instruments and 
apparatus required by various observers pursuing similar 
lines of investigation. At its meeting at Edinburgh in 
1834 it caused a comparison to be made between the 
standard bar at Aberdeen, construded by Troughton, and 
the standard of the Royal Astronomical Society, and re- 
ported that the scale ** was exceedingly well finished ; it 
was about ,^oth of an inch shorter than the 5- feet of the 
Royal Astronomical Society's scale, but it was evident 
that a great number of minute, yet important, circum- 
stances have hitherto been negleded in the formation of 
such scales, without an attention to which they cannot 
be expeded to accord with that degree of accuracy which 
the present state of science demands." Subsequently, 
at the meeting at Newcastle in 1863, the Association ap- 
pointed a committee to report on the best means of 
providing for a uniformity of weights and measures with 
reference to the interests of science. This committee 
recommended the metric decimal system — a recommend- 
ation which has been endorsed b^ a committee of the 
House of Commons in the last session of Parliament. 

British instrument-makers had been long conspicuous 
for accuracy of workmanship. Indeed, in the eighteenth 
century pradical astronomy had been mainly in the hands 
of British observers ; for although the mathematicians of 
France and other countries on the continent of Europe 
were occupying the foremost place in mathematical 
investigation, means of astronomical observation bad 
been furnished almost exclusively by English artisans. 

The sedors, quadrants, and circles of Ramsden, Bird, 
and Cary were inimitable by Continental workmen. 

Lord Kelvin said in his Presidential Address at Edin- 
burgh, ** Nearly all the grandest discoveries of science 
have been but the rewards of accurate measurement and 
patient, long-continued labour in the sifting of numerical 
results." The discovery of argon, for which Lord Ray- 
leigh and Professor Ramsay have been awarded the 
Hodgkin prize by the Smithsonian Institution, affords a 
remarkable illustration of the truth of this remark. In- 

* The litre is the voJume of a kilogramme of pure water at its 
maximum density, and is slightJy less than the litre was intended to 
be, viz., one cubic decimetre. The weight of a cnbic dedmetre of 
pore water is 1*00013 kilognni. 



CrbmicalNbwb,) 
Sept. 13, 1895. / 



British Association. — The President's Address. 



I2Q 



^eed, the provision of accurate standards not only of 
length, but of weight, capacity, temperature, force, and 
energy, are amongst the foundations of scientific investi- 
gation. 

In 1842 the British Association obtained the oppor- 
tunity of extending its usefulness in this dire^ion. 

In that year the Government gave up the Royal Observa- 
tory at Kew, and offered it to the Royal Society, who 
declined it. But the British Association accepted the 
charge. Their first obje^ was to continue Sabine's 
valuable observations upon the vibrations of a pendulum 
in various gases, and to promote pendulum observations 
in various parts of the world. They subsequently ex- 
tended it into an observatory for comparing and verifying 
the various instruments which recent discoveries in 
physical science had suggested for continuous meteor- 
ological and magnetic observations, for observations and 
experiments on atmospheric eledricity, and for the study 
of solar physics. 

This new depairture afforded a means for ascertaining 
the advantages and disadvantages of the several varieties 
of scientific instruments; as well as for standardising and 
testing instruments, not only for instrument makers, but 
especially for observers by whom simultaneous observa- 
tions were then being carried on in different parts of the 
world ; and also for training observers proceeding abroad 
on scientific expeditions. 

Its special objed was to promote original research, and 
expenditure was not to be incurred on apparatus merely 
intended to exhibit the necessary consequences of known 
laws. 

The rapid strides in eledrical science had attra^ed 
attention to the measurement of electrical resistances, 
and in 1859 the British Association appointed a special 
committee to devise a standard. The standard of resist- 
ance proposed by that committee became the generally 
accepted standard, until the requirements of that ad- 
vancing science led to the adoption of an international 
atandanl. 

In 1866 the Meteorological Department of the Board 
of Trade entered into close relations with the Kew 
Observatory. 

And in 1871 Mr. Gassiot transferred £xo,ooo upon 
trust to the Royal Society for the maintenance of the 
Kew Observatory, for the purpose of assisting in carrying 
on magnetical, meteorological, and other physical obverva- 
lions. The British Association thereupon, after having 
maintained this Observatory for nearly thirty years, at a 
total expenditure of about ^ Z2,ooo, handed the Observa- 
tory over to the Royal Society. 

The *' Transadions '* of the British Association are a 
catalogue of its efforts in every branch of science, both to 
promote experimental research and to facilitate the appli- 
cation of the results to the praAical uses of life. 

But probably the marvellous development in science 
which has accompanied the life history of the Association 
will be best appreciated by a brief allusion to the condition 
of some of the branches of science in 1831 as compared 
with their present state. 

Geox^oical and Geoqraphical Science. 
Geology. 

At the foundation of the Association geology was assu- 
ming a prominent position in science. The main features 
of English geology had been illustrated as far back as 
z8ax, and, among the founders of the British Association, 
Marchison and Phillips, Buckland, Sedgwick, and Cony- 
l>eare, Lyell and De la Beche, were occupied in investi- 
gating the data necessary for perfeding a geological 
chronology by the detailed observations of the various 
British deposits, and by their co-relation with the Con- 
tinental strata. They were thus pieparing the way for 
those large generalisations which have raised geology to 
the rank of an indudive science. 

In 183 1 the Ordnance maps published for the southern 
counties had enabled the Government to recognise the 



importance of a geological survey by the appointment of 
Mr. De la Beche to affix geological colours to the maps 
of Devonshire and portions of Somerset, Dorset, and 
Cornwall ; and in 1835 Ly^^lf Buckland, and Sedgwick 
induced the Government to establish the Geological Snr* 
vey Department, not only for promoting geological science^ 
but on account of its pradical bearing on agricultnre, 
mining, the making of roads, railways, and canals, and 
on other branches of national industry. 
Gtography. 

The Ordnance Survey appears to have had its origin in 
a proposal of the French Government to make a joint 
measurement of an arc of the meridian. This proposal 
fell through at the outbreak of the Revolution ; but the 
measurement of the base for that objed was taken as a 
foundation for a national survey. In 183 1, however, the 
Ordnance Survey had only published the z-inch map for 
the southern portion of England, and the great triango- 
lation of the kingdom was still incomplete. 

In 1834 ^^^ British Association urged upon the Govern- 
ment that the advancement of various branches of science 
was greatly retarded by the want of an accurate map of 
the whole of the British Isles ; and that, consequently, 
the engineer and the meteorologist, the agriculturist and 
the geologist, were each fettered in their scientific investi* 
gations by the absence of those accurate data which now 
lie ready to his hand for the measurement of length, of 
surface, and of altitude. 

Yet the first decade of the British Association was 
coincident with a considerable development of geographi- 
cal research. The Association was persistent in pressing 
on the Government the scientific importance of sending 
the expedition of Ross to the Autarkic and of Franklin 
to the Ardiic regions. We may trust that we are approach- 
ing a solution of the geography of the North Pole ; but 
the Antardic regions still present a field for the researches 
of the meteorologist, the geologist, the biologist, and the 
magnetic observer, which the recent voyage of M. 
Borchgrevink leads us to hope may not long remain un» 
explored. 

In the same decade the question of an alternative route 
to India by means of a communication between the 
Mediterranean and the Persian Gulf was also receiving 
attention, and in 1835 the Government employed Colonel 
Chesney to make a survey of the Euphrates valley in 
order to ascertain whether that river would enable a 
pradicable route to be formed from Iskanderooo, or 
Tripoli, opposite Cyprus, to the Peraian Gulf. His valu- 
able surveys are not, however, on a sufficiently extensive 
scale to enable an opinion to be formed as to whether 
a navigable waterway throagh Asia Minor is physically 
pra^icable, or whether the cost of establishing it might 
not be prohibitive. 

The advances of Russia in Central Asia have made it im- 
perative to provide an easy, rapid, and alternative line of 
communication with our Eastern possessions, so as not 
to be dependent upon the Suez Canal in time of war. If 
a navigation cannot be established, a railway between the 
Mediterranean and the Persian Gulf has been shown by 
the recent investigations of Messrs. Hawkshaw and 
Hayter, following on those of others, to be perfedly 
praAicable and easy of accomplishment ; such an under- 
taking would not only be of strategical value, bat it is 
believed it would be commercially remunerative. 

Speke and Grant brought before the Association, at ita 
meeting at Newcastle in 1863, their solution of the 
mystery of the Nile basin, which had puzzled geographers 
from the days of Herodotus ; and the efforts of Living- 
stone and Stanley and others have opened out to us the 
interior of Africa. I cannot refrain here from expressins 
the deep regret which geologists and geographers, and 
indeed all who are interested in the progress of discoveiy, 
feel at the recent death of Joseph Thomson. His exten- 
sive, accurate, and trustworthy observations added much 
to our knowledge of Africa, and by his premature death 
we have lost one of its most competent explorers. 



130 



British Association. — The President's Address. 



I Cbimical Nbwi, 

\ Sept. 13, 1895. 



Chbmical, Astronomical, and Physical Scibncb. 
Chemistry. 

The report made to the Association on the state of the 
chemical sciences in 1832, says that the efforts of investi- 
gators were then being direded to determining with accu- 
racy the true nature of the substances which compose the 
various produds of the organic and inorganic kingdoms, 
and the exad ratios by weight which the different con- 
stituents of these substances bear to each other. 

But since that day the science of chemistry has far ex- 
tended iU boundaries. The barrier has vanished which 
was supposed to separate the produds of living organisms 
from the substances of which minerals consist, or which 
could be formed in the laboratory. The number of dis- 
tind carbon compounds obtainable from organisms has 
greatly increased ; but it is small when compared with 
the number of such compounds which have been artifi- 
cially formed. The methods of analysis have been per- 
feded. The physical, and especially the optical, properties 
of the various forms of matter have been closely studied, 
and many fruitful generalisations have been made. The 
form in which these generalisations would now be stated 
may probably change, some, perhaps, by the overthrow or 
disuse of an ingenious guess at Nature's workings, but 
more by that change which is the ordinary growth of 
science — namely, inclusion in some simpler and more 
general view. „ . , 

In these advances the chemist has called the spedro- 
scope to his aid. Indeed, the existence of the British 
Association has been pradically coterminous with the 
comparatively newly-developed science of spedrum ana- 
lysis, for though Newton,* Wollaston, Fraunhofer, and 
Fox Talbot had worked at the subjed long ago, it was 
not till Kirchhoff and Bunsen set a seal on the prior 
labours of Stokes, Angstrdm, and Balfour Stewart that 
the spedra of terrestrial elements have been mapped out 
and grouped; that by its help new elements have been 
discovered, and that the idea has been suggested that the 
various orders of spedra of the same elements are due 
to the existence of the element in different molecular 
forms^allotropic or otherwise— at different temperatures. 

But great as have been the advances of terrestrial che- 
mistry through its assistance, the most stupendous ad* 
vance which we owe to the spedroscope lies in the celes- 
tial diredion. 

Astronomy. 

In the earlier part of this century, whilst the sidereal 
universe was accessible to investigators, many problems 
outside the solar system seemed to be unapproachable. 

At the third meeting of the Association, at Cambridge, 
in X833, Dr. Whewell said that astronomy is not only the 
queen of science, but the only perfed science, which was 
•* in so elevated a state of flourishing maturity that all 
that remained was to determine with the extreme of accu- 
racy the consequences of its rules by the profoundest 
combinations of mathematics; the magnitude of its data 
by the minutest scrupulousness of observation.'* 

But in the previous year, viz., 1832, Airy, in his report 
to the Auociation on the progress of astronomy, had 
pointed out that the observations of the planet Uranus 
could not be united in one elliptic orbit ; a remark which 
turned the attention of Adams to the discovery of Nep- 
tune. In his report on the position of optical science in 
1832, Brewster suggested that with the assistance of ade- 
quate instruments ** it would be possible to study the ac- 
tion of the elements of material bodies upon rays of arti- 
ficial light, and thereby to discover the analogies between 
their affinities and those which produce the fixed lines in 

* lomonet Marcui Marci, of KronUnd in Bohemia, wm the only 
Dredeccsaor of Newton who bad any knowledge of the formation of a 
anedrom by a piiim. He not only obMrved that the coloured raya 
diverged aa they lelt the prism, but that a coloured ray did not change 
in o^oor after tranamittion through a prism. His book, •* Thau- 
mantias, liber de arcu coelesti deque colorum appareniium nalura," 
Prag, 1648, was, however, not known to Newton, and had no infla- 
cBcc upon future discoveries. 



the spedra of the stars ; and thus to study the effeds of 
the combustions which light up the suns of other 
systems." 

This idea has now been realised. All the stars which 
shine brightly enough to impress an image of the spedrum 
upon a photographic plate have been classified on a 
chemical basis. The close connedion between stars and 
nebulae has been demonstrated ; and while on the one 
hand the modern science of thermodynamics has shown 
that the hypothesis of Kant and Laplace on stellar forma- 
tion is no longer tenable, inquiry has indicated that the 
true explanation of stellar evolution is to be found in the 
gradual condensation of meteoritic particles, thus justify- 
ing the suggestions put forward long ago by Lord Kelvin 
and Professor Tait. 

We now know that the spedra of many of the terres- 
trial elements in the chromosphere of the sun differ from 
those familiar to us in our laboratories. We be^in to 
glean the fad that the chromospheric spedra are similar 
to those indicated by the absorption going on in the 
hottest stars, and Lockyer has not hesitated to affirm that 
these fads would indicate that in those localities we are 
in the presence of the adions of temperatures sufficiently 
high to break up our chemical elements into finer forms. 
Other students of these phenomena may not agree in this 
view, and possibly the discrepancies may be due to default 
in our terrestrial chemistry. Still, I would recall to yoo 
that Dr. Carpenter, in his Presidential Address at 
Brighton in 1872, almost censured the speculations of 
Frankland and Lockyer in 1868 for attributing a certain 
bright line in the spedrum of solar prominences (which 
was not identifiable with that of any known terrestrial 
source of light) to a hypothetical new substance which 
they proposed to call ** helium," because ** it had not re- 
ceived that verification which, in the case of Crookes's 
search for thallium, was afforded by the adual discovery 
of the new metal." Ramsay has now shown that this gas 
is present in dense minerals on earth ; but we have now 
also learned from Lockyer that it and other associated 
gases are not only found with hydrogen in the solar 
chromosphere, but that these gases, with hydrogen, form 
a large percentage of the atmospheric constituents of 
some of the hottest stars in the heavens. 

The spedroscope has also made us acquainted with the 
motions and even the velocities of those distant orbs 
which make up the sidereal universe. It has enabled us 
to determine that many stars, single to the eye, are really 
double, and many of the conditions of these strange sys- 
tems have been revealed. The rate at which matter is 
moving in solar cyclones and winds is now familiar to us. 
And 1 may also add that quite recently this wonderful 
instrument has enabled Professor Keeler to verify Clerk- 
Maxweirs theory that the rings of Saturn consist of a 
marvellous company of separate moons^-as it were, a 
cohort of courtiers revolving round their queen— with 
velocities proportioned to their distances from the planet. 

Physics. 

If we turn to the sciences which are included under 
physics, the progress has been equally marked. 

In optical science, in 1831 the theory of emission as 
contrasted with the undulatory theory of light was still 
under discussion. 

Young, who was the first to explain the phenomena 
due to the interference of the rays of light as a conse* 
quence of the theory of waves, and Fresnel, who showed 
the intensity of light for any relative position of the 
interference-waves, both had only recently passed away. 

The investigations into the laws which regulate the con- 
dudion and radiation of heat, together with the dodrine 
of latent and of specific heat, and the relations of vapour 
to air, had all tended to the conception of a material heat, 
or caloric, communicated by an adual flow and emission. 

It was not till 1834 that improved thermometrical appli- 
ances had enabled Forbes and Melloni to establish the 
polarisation of heat, and thus to lay the foundation of an 



CatmciL Newt, I 
S«pc 13. 1893. f 



British Association. — The President's Address. 



131 



nndnlatory theory for heat similar to that which was in 
proKresa of acceptation for light. 

Wbewell's report, in 1832, on magnetism and eleari- 
city shows that these branches of science were looked 
upon as cognate, and that the theory of two opposite 
eiedric fluids was generally accepted. 

In magnetism, the investigations of Hansteeo, Gauss, 
and Weber in Europei and the observations made under 
the Imperial Academy of Russia over the vast extent of 
that empire, had established the existence of magnetic 
poles, and had shown that magnetic disturbances were 
nmoltaaeous at all the stations of observation. 

At their third meeting the Association urged the 
Qovemrocnt to establish magnetic and meteorological 
obeervatories in Great Britain and her colonies and 
dependencies in different parts of the earth, furnished with 
proper instruments, construded on uniform principles, 
and with provisions for continued observations at those 

In 1839 the British Association had a large share in 
iadadng the Government to initiate the valuaole ceries of 
experiments for determining the intensity, the declina- 
lioo, the dip, and the periodical variations of the magnetic 
needle, which were carried on for several years, at numer- 
cma seleded stations over the surface of the globe, under 
the dircdioos ol Sabine and Lefroy. 

In England systematic and regular observations are still 
made at Greenwich, Kew, and Stonvhurst. For some 
yeart past similar observations bv both absolute and self- 
recording instruments have also been made at Falmouth 
—dote to the home of Robert Were Fox, whose name is 
inseparably conneAed with the early history of terrestrial 
magnetism in this country — ^but under such great finan- 
ciaidifficulties that the continuance of the work is seri- 
ously Jeopardised. It is 10 be hoped that means may be 
fortbcommg to carry it on. Cornishmen, indeed, could 
loond no more fitting memorial of their distinguished 
ONiDtryman, John Couch Adams, than by suitably en- 
dowing the magnetic observatory in which he took so 
lively an interest. 

Far more extended observation will be needed before 
we can hope to have an established theory as to the mag- 
netism of the earth. We are without magnetic observa- 
tions over a large part of the Southern Hemisphere. And 
Professor Riicker's recent investigations tell us that the 
earth seems as it were alive with magnetic forces, be 
they doe to eledric currents or to variations in the state 
of magnetised matter ; that the disturbances affed not only 
the diurnal movement of the magnet, but that even the 
small part of the secular change which has been observed, 
aad wnicb has taken centuries to accomplish, is interfered 
with by some slower agency. And, what is more impor- 
taott hie tells us that none of these observations stand as 

Jet upon a firm basis, because standard instruments 
ave not been in accord ; and much labour, beyond the 
power of individnal effort, has hitherto been required to 
ascertain whether the relations between them are constant 
or variable. 

In eledricity, in 1831, just at the time when the British 
Association was founded, Faraday's splendid researches 
io eleAricity and magnetism at the Royal Institution had 
begun with his discovery of magneto- eledric indudlion, 
his investigation of the laws of eledro-chemical decom- 
position, and the mode of eledrolytical adion. 

Hot, the praAical application of our eledrical knowledge 
was then limited to the use of lightning-condudiors for 
bnOdings and ships. Indeed, it may be said that the 
applicaiions of eledricity to the use of man have grown 
«p side by side with the British Association. 

One of the first pradical applications of Fataday's 
d is coveries was in the deposition of metals and eledro- 
plating, which has developed into a large branch of 
national industry; and the dissociating effed of the 
eledric arc, for the redudion of ores, and in other pro- 
ossses, is daily obtaining a wider extension. 

But probably the application of eledricity, which is 



tending to produce the greatest change in oor mental* 
and even material condition, is the eledric telegraph and 
its sister, the telephone. By their agency not only do we 
learn, almost at the time of their occurrence, the events 
which are happening in distant parts of the world, but 
they are establishing a community of thought and feeling 
between all the nations of the worid which is inflaendng 
their attitude towards each other, and, we may hope, may 
tend to weld them more and more into one family. 

The eledric telegraph was introduced experimentally 
in Germany in 1833, two years after the formation of the 
Association. It was made a commercial success by 
Cooke and Wheatstone in England, whose first attempts 
at telegraphy were made on the line from Euston to 
Camden Town in 1837, ^^^ on the line from Paddingtoo 
to West Drayton in 1838. 

The submarine telegraph to America, conceived in 18561 
became a pradical reality in x86x through the commercial 
energy of Cyrus Field and Pender, aided by the mechan- 
ical skill of Latimer Clark, Gooch, and others, and the 
scientific genius of Lord Kelvin. The knowledge oi 
eledricity gained by means of its application to the tele- 
graph, largely assisted the extension of its utility in othst 
diredions. 

The eledric light gives, in its incandescent form« a vsiy 
perfed hygienic light. Where rivers are at hand the dec- 
trical transmission of power will drive railway trains and 
fadtories economically, and might enable each artisan to 
convert his room into a workshop, and thus assist In 
restoring to the labouring man some of the individuality 
which the fadory has tended to destroy. 

In 1843 Joule described his experiments for determiniag 
the mechanical equivalent of heat. But it was not nntH 
the meeting at Oxford, in 1847, ^^^^ ^^ ^olly developed 
the law of the conservation of energy, which, in con- 
jundion with Newton's law of the conservation of 
momentum, and Dalton's law of the conservation of che- 
mical elements, constitutes a complete mechanical 
foundation for physical science. 

Who, at the foundation of the Association, would have 
believed some far*seeing philosopher if he had foretold 
that the spedroscope would analyse the constitneats of 
the sun and measure the motions of the stars ; that we 
should liquefy air and utilise temperatures approachingto 
the absolute zero for experimental researco; that, uko 
the magician in the *< Arabian Nights," we ^lould anni- 
hilate distance by means of the eledric telegraph and the 
telephone; that we should illuminate our largest buildings 
instantaneously, with the clearness of day, by means of 
the eledric current ; that by the eledric transmission of 
power we should be able to utilise the Falls of Niagsra 
to work fadories at distant places ; that we should es* 
trad metals from the crust of the earth by the same 
eledrical agency to which, in some esses, their depositioo 
has been attributed ?^ 

These discoveries' and their applications have been 
brought to their present condition by the resesrches of a 
long line of scientific explorers, such as Dalton, JottlOt 
Maxwell, Helmholtz, Hers, Kelvin, and Rayleigh, aided 
by vast strides made in mechanical skill. But what will 
our successors be discussing sixty jrears hence ? How 
little do we yet know of the vibrations which communicate 
light and heat ! Far as we have advanced in the applica- 
tion of eledricity to the uses of life, we know but little 
even yet of its real nature. We are only on the threshold 
of the knowledge of molecular adion, or of the conttltti- 
tion of the all-pervading aether. Newton, at the end of 
the seventeenth century, in his preface to the <* Prindpia,*' 
says :— *' I have deduced the motions of the planets by 
mathematical reasoning from forces ; and I would that 
we could derive the other phenomena of Nature from 
mechanical principles by the same mode of reasoning. 
For many things move me, so that I somewhat soaped 
that all such ma^ depend on certain forces by which the 
particles of bodies, through causes not yet known, are 
either urged towards each other according to regular 



132 



British Association. — The Presidents Address. 



fCaBiiiCAtNiwt, 
I Sept. 13. 1895. 



figures, or are repelled and recede from each other ; and 
tbeae forcet being unknown, philosophers have hitherto 
made their attempts on Nature in vain.'* 

In 1848 Faraday remarked :— " How rapidly the know- 
ledge of molecular forces grows upon us, and bow 
strikingly every investigation tends to develop more and 
more their importance. 

**A few years ago magnetism was an occult force, 
aiffeding only a few bodies; now it is found to influence 
all bodies, and to possess the most intimate relation with 
ele^ricity, heat, chemical aAion, light, crystallisation ; 
and through it the forces concerned in cohesion. We 
may feel encouraged to continuous labours, hoping to 
bring it into a bond of union with gravity itself." 

But it is only within the last few years that we have 
begun to realise that eledricity is closely conneded with 
the vibrations which cause beat and light, and which 
teem to pervade all space— vibrations which may be 
termed the voice of the Creator calling to each atom and 
to each cell of protoplasm to fall into its ordained posi- 
tion, each, as it were, a musical note in the harmonious 
symphony which we call the universe. 

Meteorology, 

At the first meeting, in 1831, Prof. James D. Forbes 
was requested to draw up a report on the State of 
Meteorological Science, on the ground that this science 
is more in want than any other of that systematic 
direAion which it is one great objed of the Association 
to give. 

Professor Forbes made his first report in 1832, and a 
subsequent report in 1840. The systematic records now 
kept, in various parts of the world, of barometric 
pressure, of solar heat, of the temperature and physical 
conditions of the atmosphere at various altitudes, of the 
heat of the ground at various depths, of the rainfall, of 
the prevalence of winds, and the gradual elucidation not 
only of the laws which regulate the movements of 
cyclones and storms, but of the influences which are 
exercised by the sun and by eledricity and magnetism, 
not only upon atmospheric conditions, but upon health 
and vitality, are gradually approximating meteorology to 
the position of an exadl science. 

England took the lead in rainfall observations. Mr. 
J. G. Symons organised the British Rainfall System in 
z86o with 178 observers, a system which until 1876 re- 
ceived the help of the British Association. Now Mr. 
Symons himself conduds it, assisted by more than 3000 
observers, and these volunteers not only make the ob< 
servations, but defray the expense of their redudion and 
publication. In foreign countries this work is done by 
Government officers at the public cost 

At the present time a very large number of rain-gauges 
are in daily use throughout the world. The British 
Islands have more than 3000, and India and the United 
States have nearly as many ; France and Germany are 
not far behind ; Australia probably has more — indeed, one 
colony alone. New South Wales, has more than iioo. 

The storm warnings now issued under the excellent 
systematic organisation of the Meteorological Committee 
may be said to have had their origin in the terrible storm 
which broke over the Black Sea during the Crimean War, 
on November a7th, 1855. Leverrier traced the progress 
ol that storm, and, seeing how its path could have been 
reported in advance by the eledric telegraph, he proposed 
to establish observing stations which should report to the 
coasts the probability of the occurrence of a storm. 
Leverrier communicated with Airy, and the Government 
authorised Admiral FitzRoy to make tentative arrange- 
ments in this country. The idea was also adopted on 
the Continent, and now there are few civilised countries 
north or south of the Equator without a system of storm 
warming.* 

* It has often been supposed that Leverrier was also the first to 
issue a daily weather map, but that was not the case, for in the 
Great Exhibition of 1851 the EieAric Telegraph Company sold daily 



Biological Science. 
Botany, 

The earliest Reports of the Association which bear on 
the biological sciences were those relating to botany. 

In 183 1 the controversy was yet unsettled between the 
advantages of the Linnean, or Artificial system, as con- 
trasted with the Natural system of classification. 
Histology, morphology, and physiological botany, even if 
born, were in their early infancy. 

Our records show that von Mohl noted cell division in 
1835, the presence of chlorophyll corpuscles in 1837; and 
he first described protoplasm in 1846. 

Vast as have been the advances of physiological botany 
since that time, much of its fundamental principles 
remain to be worked out, and I trust that the establish- 
ment, for the first time, of a permanent Sedion for 
botany at the present meeting will lead the Association 
to take a more prominent part than it has hitherto done 
in the further development of this branch of biological 
science. 

Animal Physiology, 

In 1 83 1 Cuvier, who during the previous generation 
had, by the collation of fadts followed by careful indudive 
reasoning, established the plan on which each animal it 
construded, was approaching the termination of his long 
and useful life. He died in 1832; but in 1831 Richard 
Owen was just commencing his anatomical investigations 
and his brilliant contributions to palaeontology. 

The impulse which their labours gave to biological 
science was refieded in numerous reports and communi- 
cations, by Owen and others, throughout the early 
decades of the British Association, until Darwin pro- 
pounded a theory of evolution which commanded the 
general assent of the scientific world. For this theory 
was not absolutely new. But just as Cuvier had shown 
that each bone in the fabric of an animal affords a clue 
to the shape and strudure of the animal, so Darwin 
brought harmony into scattered fads, and led us to per- 
ceive that the moulding hand of the Creator may have 
evolved the complicated strudures of the organic world 
from one or more primeval cells. 

Richard Owen did not accept Darwin's theory of evo- 
lution, and a large sedion of the public contested it. I 
well remember the storm it produced— a storm of praise 
by my geological colleagues, who accepted the result of 
investigated fads ; a storm of indignation, such as that 
which would have burned Galileo at the stake, from those 
who were not yet prepared to question the old authorities ; 
but they diminish daily. 

We are, however, as yet only on the threshold of the 
dodrine of evolution. Does not each fresh investigation, 
even into the embryonic stage of the simpler forms of 
life, suggest fresh problems ? 

Anthropology, 

The impulse given by Darwin has been fruitful in lead- 
ing others to consider whether the same principle of evo- 
lution may not have governed the moral as well as the 
material progress of the human race. . . . Evolution, 
as Sir William Flower said, is the message which biology 
has sent to help us on with some of the problems of 
human life, and Francis Galton urges that man, the fore- 
most outcome of the awful mystery of evolution, should 
realise that he has the power of shaping the course of 
future humanity by using his intelligence to discover and 
expedite the changes which are necessary to adapt cir- 
cumstances to man, and man to circumstances. 

In considering the evolution of the human race, the 
science of preventive medicine may afibrd us some indi- 
cation of the diredion in which to seek for social improve- 
ment. One of the earliest steps towards establishing that 

weather maps, copies of which are still in existence, and the data for 
them were, it is believed, obtained by Mr. James Glaisher, F.R.S., 
at that time Superintendent of the Meteorological Department at 
Greenwich. 



British Association. — The President's Address. 



Cbsmicai. Nbws, I 
Scpi. 13, 1895. I 

science upon a secure basis was taken in 1835 by the 
British Association, who urged upon the Government the 
necessity of establishing registers of mortality showing 
the cause of death ** on one uniform plan in all parts of 
the King's dominions, as the only means by which 
general laws touching the influence of causes of disease 
and death could be satisfadorily deduced." The general 
registration of births and deaths was commenced in 1838. 
But a mere record of death and its proximate cause is in- 
sufficient. Preventive medicine requires a knowledge of 
the details of the previous conditions of life and of occu- 
pation. Moreover, death is not our only or most dangerous 
enemy, and the main objed of preventive medicine is to 
ward off disease. Disease of body lowers our useful 
energy. Disease of body or of mind may stamp its curse 
on succeeding generations. 

The anthropometric laboratory affords to the student of 
anthropology a means of analysing the causes of weakness, 
not only in bodily, but also in mental life. 

Mental adions are indicated by movements and their 
results. Such signs are capable of record, and modern 
physiology has shown that bodily movements correspond 
to aAion in nerve-centres, as surely as the motions of 
the telegraph indicator express the movements of the 
operator's hands in the distant office. 

Thus there is a relation between a defedive status in 
brain power and defeds in the proportioning of the body. 
Defeds in physiognomical details, too finely graded to be 
measured with instruments, may be appreciated with 
accuracy by the senses of the observer ; and the records 
Bhow that these defeds are, in a Urge degree, associated 
with a brain status lower than the average in mental 
power. 

A report presented by one of your committees gives the 
results of observations made on 100,000 schoolchildren 
examined individually in order to determine their mental 
and physical condition for the purpose of classification. 
This shows that about 16 per 1000 of the elementary 
school population appear to be so far defective in their 
bodily or brain condition as to need special training to 
enable them to undertake the duties of life, and to keep 
them from pauperism or crime. 

Many of our feeble-minded children, and much disease 
and vice, are the outcome of inherited proclivities. 
Francis Galton has shown us that types of criminals 
which have been bred true to their kind are one of the 
saddest disfigurements of modern civilisation ; and he 
tays that few deserve better of their country than those 
who determine to lead celibate lives through a reasonable 
convidion that their issue would probably be less fitted 
than the generality to play their part as citizens. 

These considerations point to the importance of pre- 
venting those suffering from transmissible disease, or the 
criminal, or the lunatic, from adding fresh sufferers to 
the teeming misery in our large towns. And in any case, 
knowing as we do the influence of environment on the 
development of individuals, they point to the necessity 
of removing those who are born with feeble minds, or 
under conditions of moral danger, from surrounding 
deteriorating influences. 

These are problems which materially affed the progress 
of the human race, and we may feel sure that, as we 
gradually approach their solution, we shall more cer- 
tainly realise that the theory of evolution, which the 
fenius of Darwin impressed on this century, is but the 
rst step on a biological ladder which may possibly even- 
tually lead us to understand how in the drama of creation 
man has been evolved as the highest work of the Creator^ 

Bacttriology, 
The sciences of medicine and surgery were largely 
represented in the earlier meetings of the Association, 
before the creation of the British Medical Association 
afforded a field for their more intimate discussion. The 
close connedion between the different branches of science 
is causing a revival in our proceedings of discussions on 



133 



some of the highest medical problems, especially those 
relating to the spread of infedioos and epidemic disease. 

It is interesting to contrast the opinion prevalent at 
the foundation of the Association with the present poaition 
of the question, 

A report to the Association in 1834, by Professor Heoiy, 
on contagion, says :— 

"The notion that contagions emanations are at all 
conneded with the diffusion of animalculae through the 
atmosphere is at variance with all that is known of the 
diffusion of volatile contagion.*' 

Whilst it had long been known that filthy conditiona in 
air, earth, and water fostered fever, cholera, and many 
other forms of disease, and that the disease ceased to 
spread on the removal of these conditions, yet the reason 
for their propagation or diminution remained nnder a 
veil. 

Leeuwenhoek in 1680 described the yeast-cells, but 
Schwann in 1837 ^^^ showed clearly that fermeota* 
tion was due the adivity of the yeast-cells ; and* 
although vague ideas of fermentation had been 
current during the past century, he laid the founda- 
tion of our exad knowledge of the nature of the 
adion of ferments, both organised and unorganised. It 
was not until i860, after the prise of the Academy of 
Sciences had been awarded to Pasteur for his essay 
against the theory of spontaneous generation, that his in- 
vestigations into the adion of ferments* enabled bim to 
show that the effeds of the yeaat-cell are indissolubly 
bound up with the adivities of the cell as a living 
organism, and that certain diseases, at least, are due to 
the adion of ferments in the living being. In 1865 he 
showed that the disease of silk worms, which was then 
undermining the silk industry in France, could be success- 
fully combated. His further researches into anthrax, 
fowl cholera, swine fever, rabies, and other diseases 
proved the theory that those diseases are conneded in 
some way with the introdudion of a microbe into the 
body of an animal ; that the virulence of the poison can 
be diminished by cultivating the microbes in an appro- 
priate manner; and that when the virulence has been 
thus diminished their inoculation will afford a protedion 
against the disease. 

Meanwhile it had often been observed in hospital 
pradice that a patient with a simple-fradured limb was 
easily cured, whilst a patient with a compound fradnre 
often died from the wound. Lister was thence led, in 
1865, to adopt his antiseptic treatment, by which the 
wound is proteded from hostile microbes. 

These investigations, followed by the discovery of the 
existence of a multitude of micro-organisms and the re- 
cognition of some of them— such as the bacillus of tubercle 
and the comma bacillus of cholera— as essential fadort 
of disease ; and by the elaboration by Koch and others of 
methods by which the several organisms might be iso- 
lated, cultivated, and their histories studied, have gradu- 
ally built up the science of baderiology. Amongst later 
developments are the discovery of various so<cafled anti- 
toxins, such as those of diphtheria and tetanus, and the 
utilisation of these for the cure of disease. Lister's treat- 
ment formed a landmark in the science of surgery, and 
enabled our surgeons to perform operations never before 
dreamed of ; whilst later discoveries are tending to place 
the pradice of medicine on a firm scientific basis. And 
the science of baderiology is leading us to recur to strin- 
gent rules for the isolation of infedious disease, and to 
the disinfedion (by superheated steam) of materials which 
have been in contad with the sufferer. 

These microbes, whether friendly or hostile, are all 
capable of multiplying at an enormous rate under favour- 



* In speaking of fennenti one must bear in mind that there are 
two classes of ferments : one, living beings, such as veast— ** organ- 
ised " ferments, as they are sometimes caJled—the other the prodnda 
of living beings themselves, such as pepsin, Ac.,— >** onorganiaed '* 
fermenu. Pasteur worked with the former, vary littlt with the 
latter. 



U4 



British Association. — The Presidents Address. 



I CRsmcAL News, 
I Sept. 13, 1895. 



able cooditions. They are found in the air, in water, in 
the soil ; but, fortanately, the presence of one species ap- 
pears to be detrimental to other species, and sunshine, or 
even light from the sky, is prejudicial to most of them. 
Our bodies, when in health, appear to be furnished with 
special means of resisting attacks, and, so far as regards 
their influence in causing disease, the success of the 
attack of a pathogenic organism upon an individual 
depends, as a rule, in part at least, upon the power of 
resistance of the individual. 

But notwithstanding our knowledge of the danger 
arising from a state of low health in individuals, and of 
the universal prevalence of these micro-organisms, how 
careless we are in guarding the health conditions of 
every-day lifel We have ascertained that pathogenic 
organisms pervade the air. Why, therefore, do we allow 
our meat, our fish, our vegetables, our easily-contaminated 
milk, to be exposed to their inroads, often in the foulest 
localities ? We have ascertained that they pervade the 
water we drink, yet we allow foul water from our dwel- 
lings, our pig-sties, our farmyards, to pass into ditches 
without previous clarification, whence it flows into our 
streams and pollutes our rivers. We know the conditions 
of occupation which foster ill-health. Why, whilst we 
remove outside sources of impure air, do we permit the 
occupation of foul and unhealthy dwellings ? 

The study of badeiiology has shown us that although 
some of these organisms may be the accompaniments of 
disease, yet we owe it to the operation of others that the 
refuse caused by the cessation of animal and vegetable 
life is re-converted into food for fresh generations of plants 
and animals. 

These considerations have formed a point of meeting 
where the biologist, the chemist, the physicist, and the 
statistician unite with the sanitary engineer in the appli- 
cation of the science of preventive medicine. 

Enoinbbrino. 
Sewage Purification, 

The ear^y reports to the Association show that the 
laws of hydrostatics, hydrodynamics, and hydraulics, 
necessary to the supply and removal of water through 
pipes and conduits, had long been investigated by the 
mathematician. But the modem sanitary engineer has 
been driven by the needs of an increasing population to 
call in the chemist and the biologist to help him to provide 
pure water and pure air. 

The purification and the utilisation of sewage occupied 
the attention of the British Association as early as 1864, 
and between 1869 and 1876 a committee of the Associa- 
tion made a series of valuable reports on the subjedt. 
The dired application of sewage to land, though efieAive 
as a means of purification, entailed difficulties in 
thickly settled distrids, owing to the extent of land 
reouired. . . . 

It was not till the chemist called to his aid the biologist 
that a scientific system of sewage purification was 
evolved. The valuable experiments made in recent years 
by the State Board of Health in Massachusetts have 
more clearly explained to us how by this system we may 
utilise micro-oreaoisms to convert organic impurity in 
sewage into food fitted for higher forms of life. 

To effed this we require, in the first place, a filter 
about 5 feet thick of rand and gravel, or, indeed, of any 
material which affords numerous surfaces or open pores. 
Secondly, that after a volume of sewage has passed 
through the filter, an interval of time be allowed, in which 
the air necessary to support the life of the micro*organisms 
is enabled to enter the pores of the filter. Thus this 
system is dependent upon oxygen and time. Under such 
conditions the organisms necessary for purification are 
sure to establish themselves in the filter before it has 
been long in use. Temperature is a secondary consider- 
ation. 

Inperfed purification can invariably be traced either 
to a lack of oxygen in the pores of the filter, or to the 



sewage passine through so quickly that there is not suffi- 
cient time for the necessary processes to take place. And 
the power of any material to purifv either sewage or 
water depends almost entirely upon its ability to hold a 
sufficient proportion of either sewage or water in cootad 
with a proper amount of air. 

Smoke Abatement, 

Whilst the sanitary engineer has done much to improve 
the surface conditions of our towns, to furnish clean 
water, and to remove our sewage, he has as yet done 
little to purify town air. Fog is caused by the floating 
particles of matter in the air becoming weighted with 
aqueous vapour ; some particles, such as salts of ammo- 
nia or chloride of sodmm, have a greater affinity for 
moisture than others. You will suffer from fog so long 
as you keep refuse stored in your towns to furnish ammo- 
nia, or so long as you allow youf street surfaces to supply 
dust, of which much consists of powdered horse manure, 
or so long as you send the produds of combustion into 
the atmosphere. Therefore, when you have adopted me- 
chanical tradion for your vehicles in towns you may 
largely reduce one cause of fog. And if you diminish 
your black smoke, you will diminish black fogs. 

In manufadories you may prevent smoke either by care 
in firing, by using smokeless coal, or by washing the soot 
out of the produds of consumption in its passage along 
the flue leading to the main chimney-shaft. 

The black smoke from your kitchen may be avoided 
by the use of coke or of gas. But so long as we retain 
the hygienic arrangement of the open fire in our livioff 
rooms I despair of finding a fireplace, however well 
eonstruded, which will not be used in such a manner as 
to cause smoke, unless, indeed, the chimneys were 
reversed and the fumes drawn into some central shaft, 
where they might be washed before being passed into the 
atmosphere. 

Eledricity as a warming and cooking agent would be 
convenient, cleanly, and economical when generated by 
water power, or possibly wind power, but it is at present 
too dear when it has to be generated by means of coal. 
I can conceive, however, that our descendants may learn 
so to utilise eledricity that they in some future century 
may be enabled by its means to avoid the smoke in their 
towns. 

Mechanical Engineering, 

In other branches of civil and mechanical engineering 
the reports in 1831 and 1832, on the state of this science, 
show that the theoretical and pradical knowledge of the 
strength of timber had obtained considerable develop- 
ment ; but in 1830, before the iotrodudion of railways, 
cast-iron had been sparingly used in arched bridges for 
spans of from 160 to 200 feet, and wroughto'ron had only 
been applied to large-span iron bridges on the suspension 

Srinciple, the most notable instance of which was the 
lenai Suspension Bridge, by Telford. Indeed, whilst the 
strength of timber had been patiently investigated by 
engineers, the best form for the use of iron girders and 
struts was only beginning to attrad attention, and the 
earlier volumes of our Proceedings contained numerous 
records of the researches of Eaton Hodgkinson, Barlow, 
Rennie, and others. It was not until twenty years later 
that Robert Stephenson and William Fairbairn ereded 
the tubular bridge at Menai, followed by the more scien- 
tific bridge ereded by Brunei at Saltasb. These have 
now been entirely eclipsed by the skill with which the 
estuary of the Forth has been bridged with a span of 
1700 feet, by Sir John Fowler and Sir Benjamin Baker. 

The development of the iron industry is due to the 
association of the chemist with the engineer. The intro- 
dudion of the hot blast by Neilson, in 1829, in the manu- 
fadure of cast-iron, had efieded a large saving of fuel. 
But the chemical conditions which affed the strength and 
other qualities of iron, and its combinations with carbon, 
silicon, phosphorus, and other substances, had at that 
time scarcely been investigated. 



Casuic4L Niws, I 
Sept. 13, 1895. f 



British Association. — The President's Address. 



135 



In 1856 Bessemer brought before the British Associa- 
tion, at Cheltenham, his brilliant discovery for making 
tteel dire^ from the blast furnace, by which he dispensed 
with the laborious process of first removing the carbon 
from pig-iron by puddling, and then adding by cementa- 
tion the required proportion of carbon to make steel. 
This discovery, followed by Siemens*s regenerative fur- 
nace, by Whitworth*s compressed steel, and by the use of 
alloys, and by other improvements too numerous to men- 
tion here, have revolutionised the conditions under which 
metals are applied to engineering purposes. 

Indeed, few questions are of greater interest, or possess 
more industrial importance, than those conneAed with 
metallic alloys. This is especially true of those alloys 
which contain the rarer metals; and the extraordinary 
effeds of small quantities of chromium, nickel, tungsten, 
and titanium, on certain varieties of steel, have exerted 
profound influence on the manuCaAure of projediles and 
on the construdion of our armoured ships. 

Oi late years, investigations on the properties and 
ttiuAure of alloys have been numerous, and among the 
more noteworthy researches may be mentioned those of 
Dewar and Fleming on the distindiive behaviour, as re- 
gards the thermo-ele^ric powers and eledrical resistance, 
of metals and alloys at the very low temperatures which 
may be obtained by the use of liquid air. 

Professor Roberts-Austen, on the other hand, has care- 
fully studied the behaviour of alloys at very high temper- 
atures, and by employing his delicate pyrometer has 
obtained photographic curves which afford additional evi- 
dence as to the existence of allotropic modifications of 
metals, and which have materially strengthened the view 
that alloys are closely analogous to saline solutions. In 
this connexion it may be stated that the very accurate 
work of Heycock and Neville, on the lowering of the 
solidifying points of molten metals, which is caused by 
the presence of other metals, affords a valuable contribu- 
tion to our knowledge. 

Professor Roberts-Austen has, moreover, shown that 
the effed of any one constituent of an alloy upon the 
properties of the principal metal has a diredk relation to 
the atomic volumes, and that it is consequently possible 
to foretell, in a great measure, the effeA of any given 
combination. 

A new branch of investigation, which deals with the 
niicro-strudure of metals and alloys, is rapidly assuming 
much importance. It was instituted by Sorby in a com- 
munication which he made to the British Association in 
1864, and its development is due to many patient workers, 
among whom M. Osmond occupies a prominent place. 

Metallurgical science has brought aluminium into use 
by cheapening the process of its extradion ; and if by 
means of the wasted forces in our rivers, or possibly of 
the wind, the extradiion be still further cheapened by the 
aid of eledricity, we may not only utilise the metal or its 
alloys in increasing the spans of our bridges, and in 
affording strength and lightness in the coostrudion of our 
ships, but we may hope to obtain a material which may 
render pradicable the dreams of Icarus and of Maxim, 
and for purposes of rapid transit enable us to navigate 
the air. 

Long before 183 1 the steam-engine had been largely 
osed on rivers and lakes, and for short sea passages, 
although the first Atlantic steam-service was not esta- 
blished till 1838. 

As early as 1820 the steam-engine had been applied by 
Gomey, Hancock, and others to road tra&ion. The ab- 
surd impediments placed in their way by road trustees, 
which, indeed, are still enforced, checked any progress. 
But the question of mechanical tradion on ordinary roads 
was pradically shelved in 1830, at the time of the forma- 
tion of the British Association, when the locomotive 
engine was combined with a tubular boiler and an iron 
road on the Liverpool and Manchester Railway. 

Great, however, as was the advance made by the loco- 
motive engine of Robert Stephenson, these earlier engines 



were only toys compared with the compound engines of 
to-day which are used for railways, for ships, or for the 
manufadure of eledricity. Indeed, it may be taid that 
the study of the laws of heat, which have led to the in- 
trodudion of various forms of motive power, are gradoally 
revolutionising all our habits of life. 

The improvements in the produdion of iron, combined 
with the developed steam-engine, have completely altered 
the conditions of our commercial intercourse on land ; 
whilst the changes caused by the effeds of these improve- 
ments in ship-building, and on the ocean carrying trade« 
have been, if anything, still more marked. • • • 

The use of iron favours the construdion of ships of a 
large size, of forms which afford small resistance to the 
water, and with compartments which make the ships prac- 
tically unsinkable in heavy seas, or by collision. Their 
size, the economy with which they are propelled, and the 
certainty of their arrival cheapens the cost of transport. 

The steam-engine, by compressing air, gives us control 
over the temperature of cool chambers. In these, not 
only fresh meat, but the delicate produce of the Antipodes, 
is brought across the ocean to our doors without deterior- 
ation. 

Whilst railways have done much to alter the social con- 
ditions of each individual nation, the application of iron 
and steam to our ships is revolutionising the international 
commercial conditions of the world ; and it is gradually 
changing the course of our agriculture, as well as of our 
domestic life. 

But great as have been the developments of science is 
promoting the commerce of the world, science is asserting 
its supremacy even to a greater extent in every depart* 
ment of war. And perhaps this application of science 
affords at a glance, better than almost any other, a con* 
venient illustration of the assistance which the chemical, 
physical, and eledrical sciences are affording to the 
engineer. 

The reception of warlike stores is not now left to the 
uncertain judgment of **pradical men,** but is confided 
to officers who have received a special training in chemt* 
cal analysis, and in the application of physical and elec* 
trical science to the tests by which the qualities of explo- 
sives, of guns, and of projediles can be ascertained** 

For instance, take explosives. Till quite recently black 
and brown powders alone were used, the former as old at 
civilisation, the latter but a small modem improvement 
adapted to the increased size of giins. But now the whole 
famfly of nitro-explosives are rapidly superseding the old 
powder. These are the dired outcome of chemical 
knowledge; they are not mere chance inventions, for 
every improvement is based on chemical theories, and 
not on random experiment. 

The construdion of guns is no longer a haphazard 
operation. In spite of the enormous forces to be con* 
trolled and the sudden violence of their adion, the re- 
searches of the mathematician have enabled the just pro- 
portions to be determined with accuracy; the labours of 
the physicist have revealed the internal conditions of the 
materials employed, and the best means of their favour- 
able employment. Take, for example, Longridge's coiled* 
wire system, in which each successive layer of which the 
gun is formed receives the exad proportion of tension 
which enables all the layers to ad in unison. The che- 
mist has rendered it clear that even the smallest quanti* 
ties of certain ingredients are of supreme importance in 
affeding the tenacity and trustworthiness of the 
materials. 

The treatment of steel to adapt it to the vast range of 
duties it has to perform is thus the outcome of patient 
research. And the use of the metals — manganese, chro- 
mium, nickel, molybdenum— as alloys with iron has re- 
sulted in the produdion of steels possessing varied and 
extraordinary properties. The steel required to resist the 
conjugate stresses developed, lightning-fashion, in a gun 
necessitates qualities that would not be suitable in the 
projedile which that gun hurla with a velocity of some 



136 



British Association, — The President's Address. 



I Orbmical Niwt, 
1 Sept. 13, ifc95. 



8500 feet per BecoDd against the armoured side of a ship. 
The armour, again, has to combine extreme superficial 
hardness with great toughness, and during the last few 
years these qualities are sought to be attained by the ap- 
plication of tne cementation process for adding carbon to 
one face of the plate, and hardening that face alone by 
rapid refrigeration. 

The introdudion of quick-firing guns from 0*303 (f.«., 
about one-third) of an inch to 6-inch calibre has rendered 
necessary the produdtion of metal cartridge-cases of com- 
plex focms drawn cold out of solid blocks or plate of the 
material; this again has taxed the ingenuity of the 
mechanic in the device of machinery, and of the metal- 
lurgist in producing a metal possessed of the necessary 
duSility and toughness. The cases have to stand a pres- 
sure at the moment of firing of as much as twenty-five 
tons to the square inch— a pressure which exceeds the 
ordinary clastic limits of the steel of which the gun itself 
is composed. 

There is nothing more wonderful in praAical mechanics 
than the closing of the breech openings of guns, for not 
only must they be gas-tight at these tremendous pres- 
sures, but the mechanism must be such that one man by 
a single continuous movement shall be able to open or 
close %ht breech of the largest gun in some ten or fifteen 
seconds. 

The perfed knowledge of the recoil of guns has enabled 
the readion of the discharge to be utilised in compressing 
air or springs by which guns can be raised from concealed 
positiooB in order to deliver their fire, and then made to 
disappear again for loading; or the same force has been 
used to run up the guns automatically immediately after 
firing, or, as in the case of the Maxim gun, to deliver in 
the same way a continuous stream of bullets at the rate 
of ten in one second. 

In the manufadure of shot and shell cast-iron has been 
almost superseded by cast and wrought steel, though the 
hardened Palliser projediles still hold their place. The 
forged-steel projediles are produced by methods very 
similar to those used in the manufadture of metal cartridge- 
cases, though the process is carried on at a red heat and 
by mSichines much more powerful. 

In every department concerned in the produAion of 
war- like stores eledricity is playing a more and more im- 
portant part. It has enabled the passage of a shot to be 
followed from its seat in the gun to its destination. 

In the gun, by means of eledrical contads arranged in 
the bore, a time curve of the passage of the shot can be 
determined. 

From this the mathematician construds the velocity- 
curve, and from this, again, the pressures producing the 
velocity are estimated, and used to check the same indi- 
cations obtained by other means. The velocity of the 
shot after it has left the gun is easily ascertained by the 
Boulang6 apparatus. 

Eledricity and photography have been laid under con- 
tribution for obtaining records of the flight of projediles 
and the effeds of explosions at the moment of their occur- 
rence. Many of you will recoiled Mr. Vernon Boys' 
marvellous photographs showing the progress of the shot 
driving before it waves of air in its course. 

Eledricity and photography also record the properties 
of metals and their alloys as determined by curves of 
cooling. 

The readiness with which eledrical energy can be con- 
verted into heat or light has been taken advantage of for 
the firine of guns, which in their turn can, by the same 
agencv, be laid on the objed by means of range-finders 
placed at a distance and in advanta|;eous and safe posi- 
tions ; while the eledric light is utilised to illumine the 
sights at night, as well as to search out the objeds of 
attack. 

The compad nature of the glow-lamp, the brightness of 
the light, the circumstance that the light is not due to 
combustion, and therefore independent of air, facilitates 
the examination of the bore of guns, the insides of 



shells, and other similar uses— just as it is used by a 
dodor to examine the throat of a patient. 
(To be continaed). 



A REFORM IN CHEMICAL. PHYSICAL, AND 

TECHNICAL CALCULATIONS. 

By C. J. HANSSBN, C.B. 

(Continaed from p. 103). 

The ixlirnal caloric work of steamy which is overcoming 
atmospheric or other outer resistance, and is able to do 
mechanical or dynamic work, is, pro x cbm. steam pro 
X atmosphere pressure, at any temperature b 24I calors. 
pro X kg. steam - absolute temperature. consequenUy- 
9 

At ai9l» absol » ?i?l* . 24! calors. 

9 

Atays** M «^° -30J „ 

At 373* „ (I atmoBph.) - ^1^ « 4x5 „ 

9 

At 454° „ (10 atmosph.) - 15£ „ ^^ ^^ 

9 
The produd of absolute pressure x volume per kg. 
(V X P) increases in dired ratio to the absolute temper- 
ature of steam, as shown by the diagonal straight V P 
line in the diagram. 

ComhustioH. 
When a substance is burnt we feel the heat produced, 
and see flames and light emit from the burning objed, 
and we have been thus led to imagine that it is the 
visible objed only which burns, and the heat developed 
in the process of burning we commonly consider to be 
the quantity of heat which the burning substance — for 
instance, x kg. of coal — is able to produce ; we may, 
however, just as well reverse the case, and consider the 
heat developed in the process of combustion as produced 
by combining a certain quantity of oxygen with the 
burning substance, and measure the heat produced by the 
quantity of oxygen which combines with the burning 
substance. 

All substances combine with other substances in 
simple definite proportions, and this rule also holds 
good in the chemical process termed combustion ; we 
may therefore be sure that x kg. of oxygen, when com- 
bining with any other substance, always will produce the 
same quantity of heat^ just as well as x kg. of carbon, if 
in combustion or by any other chemical process combined 
with oxygen, always produces a certain and definite quan- 
tity of heat. If experience in some cases seems to coo- 
tradid this rule, and apparently gives different results, 
this can only be caused by imperfedions in the metlK>d 
and apparatus used in the research, and such anomalies 
will by-and-bye be found out and correded. 

Of all substances at our disposal, capable of producing 
heat, carbon, hydrogen, and oxygen are the most gene- 
rally applicable ; and a corred determination of the value 
of their compounds as producers of heat will therefore be 
of the highest importance for science and industry, bat 
as yet the chief authorities disagree on this subjed. 

The quantity of heat produced by combustion of x kg. 
of hydrogen of 273*^ absolute, with 8 kg. of oxygen of the 
same temperature, is found by — 

Calora. 

Andrews » 33881^ 

Humphrys . • . • • . « 34722 | The vapotir pro- 
Favre and Silbermann « 344621 duced condensed 

Dulong (V 34742 Y to liquid water 

Thomsen » 34x8i ofo°Nsa73**b- 

Fischer .. .. •• » 34384 solute. . 
Berthelot * 34600 J \ 



S«pt. 13. 1895. I 



Re/arm in Chemical, Physical^ and Technical CalculatiMS. 137 



and tht qaantity of heat produced by combustion of i kg. 

of carbon monoxide with oxygen it found by— 

Favre and Silbermann . . » 2403 calors. 

Dolong - 2489 „ 

Fischer • .. « 2440 », 

Ferguson Bell .. •• •• » 2444 •» 
Homphrys « 2489 ,, 

As not two of these agree, it seems evident that all are 
more or l^s erroneous. 

The author has shown (Chbmical Nbws, Ixxii., p. 8) 
that I kg. hydrogen of o^ N (273^ N absol.) burnt with 
8 kg. oxygen, and the produ^ of combustion condensed 
to toe initial temperature of the components, produces 
3467970 calors., which in all following calculations is 
roanded off to 34680 calors. 

This figure, being the mean of Messrs. Humphrys, 
Favre and Silbermann's, Dulong, and Berthelot's deter* 
ninations, the author considers to be a corred standard, 
from which the heating power of other substances may 
be calculated, and consequently we find that — 

I cbm. of hydrogin of atmospheric density and o^ N, 
which weighs ^ kg., will produce 34680 x A»3096| 
calors; that» 

s kf. otoxfgim will produce li|§2»4335 calors., and» 

o 

I cbm. of oxygiH of atm. density and o* N-4335 x V » 

61921 calors., and x litre oxygen r'^' •■ 6^/^ « 

1000 

fIS calors ; and further — 
t kg, of aliform carbon, burning with ik kg. oxygen, 

will produce 4335 x xl »578o calors., forming 2k kg. 

CO. 
I cbm. of atriform carbon (atmospheric density and o^ N), 

bof nt with X cbm. oxygen 01 equal density and tem- 
perature, will produce 6x92! cal. x i cbm. 0*6192! 

calors., fof ming 2 cbm. CO. 
I kg. [of atriform carbon, burning with 2} kg. oxygen, 

will produce 4335 X 2} ax 1560 calors., forming 3} kg. 

COa; and— 
s cbm aeriform carbon^ burning with 2 cbm. oxygen, will 

produce 6192I cal. x a * 13385! calors., forming 2 

cbm. COa. 
I kg. ot carbon monoxide, which contains f kg., of aeriform 

carbon, burning with f kg. oxygen, will produce 

I X 4535 cal. a 2477f calors., forming 1% kg. COa; 

and— 
I cbm. of carbon monoxide, which contains k cbm. of 

airiform carbon, burning with \ cbm. ox3rgen, will 

produce 6192! X i » 3096I calors., forming x cbm. 

COa. 
The heat produced by x kg. pure fixed carbon^ burnt 
with x} oxygen to CO, and with 2| kg. O to COa» is given 
differently 1^ various authorities ; but the mean of their 
lesttlts is f of the heat produced by burning atriform 
carbon ; and this leads to the following simple relation x-^ 

I kg. of aeriform carbon^ burnt to COa, pro- 
duces sensible heat mi 1560 calors. 

I kg. of solid carbon produces likewise 
XX560 calors., but in gasifying the fixed 
carbon | x 1x560 become latent •• * 3302( „ 

And only f X XX560 cal •• s 8257^ m 

are set free as sensible heat. 
I kg. of soUd carbon, burnt to CO, pro- 

duces i X X 1560 cal «578o calort. 

In gasifying become latent .. •• »3302| „ 

And the sensible heat produced it •• •■2477! „ 
Combustion of Hydrocarbons, 
If hydrocarbon gases burn with oxygen or air the case 
ia different, because the compound must be decomposed 
belore its components can unite with the oxygen to form 
the new compounds COa ^d HgO. 



Decomposing a hydrocarbon gas, or separating the by* 
drogen contained in it from the carbon, by the united 
action of heat and the chemical affinity of oxygen, will 
absorb half the heat produced by the H in the hydro- 
carbon ; consequently is absorbed or becoming latent :— 

Pro X cbm. H of atm. density and o® N (273* abeol.)^ 

and pro x kg.H— 



being 



a 

We find thus, the produas of combustion 
cooled down to o« N (273* N absol.), that— 
X cbm. methane of x atm. and zyz"" N absol., 
burnt with a cbm. oxygen, produces 

2x6i92fcal. -i3385fcalorfc 

Separating 2 cbnf. H from C absorbs 
axx548,\cal - 3096I ,» 

Consequently x cbm. methane produces 

sensible htSLi gaSol 

or exaaiy f of what would be due for 

the 2 cbm. O burnt with it. 
X kg. methane, burnt with 4 kg. O, produces 

4x4335 cal. • X7340 calors. 

Separating ^ kg. H from C absorbs 

ixx7340cal - 4335 » 

Consequently x kg. methane produces 
sensible heat m X3005 

Or likewise } of what would be due to the ' 

4 kg. O consumed, while } of the heat 
adually produced becomes latent. 

In a similar way we find the sensible heat produced by 
combustion of the total heat due to the O. 



xcbm. ..barot Sentible 
with heat. 
Cbm.O. Calors. 
Acetylene • . 2| X3933f| 



I kf . barat Seniibla 



Ethylene 
Ethane •• 
Allylene • . 
Propylene.. 
Propane . . 
Botylene •• 
Butane • , 
Pentane • • 
Benxenegas yk 



Coal gas, 
absolute :— 



CoQtaioi Utret 

Methane .. 370*0x2 
Ethylene .. 25-0x3 
Propylene .. 12-0x4* 
Bensene .. X3-oX7« 
Carbon monoxide 52*5 x h 
Hydrogen ,. 490*0 x h 



x/xo 
1/6 

x/8 
1/6 



with heat. Saotib. Latest 
Kf.O. OUort. 

___._, 3iV 12004A 

3 X548af 3l "385! 
3» 17030A 3!1 X27X6 

4 21685 3} iax38 
4J 23223A 31 ia385f 
I H77II 3fr ia6xoff 
6 30964? 31 I2385» 
6* 32512* 3» 12556*: 
8 402531 31 12523* 

418OXH Zi*M I2004A 
Combustion of Mixed Oases. 
X7 candles, x cbm. atm. density, 273^ N 



9/10 
5/6 

ax/26 5/26 

a5/3a 7/3* 
9/10 x/io 



Carbon dioxide 
Nitrogen 
Oxygen .. .. 



40 

32-5 
x-o 



Requires 
oayfeo 
Litres. 

- 7400 

- 75-0 

- 540 

- 97*5 
•■ 26*35 

- 845-0 

"3775 
t-oo 



Prodocei tcaiible 

heatcqnalio 

UtreaO. 

7400 Xi »555'oo 

750x1 - 6a-50 

54-OXf » 4500 

975 X A- «775 

a6*a5 

a45*oo 



1*00 



X cbm. gas* xooo-o requires xa3675 O, of which 1032*30 
litres O only produce sensible heat, and develope— 

1036-5 X ??? „ 6332 •X96 calors. sensible heat. 
X40 

One cbm. of this gas weight 5853/11200 kg.; x kg. there- 
fore contains xxaoo/5853 cbm., will for combustion 



fcqoire 2*36565 cbm. Omsy^ygs kg. O, and will produce 
131x6-965 calort. of sentible heat. 

Wai4r Oatt H+ CO.— This mixed gat, which consists 
of equal volomei of H and CO, is formed when steam 
through glowing carbon ; the H of the steam is 



138 Reform in Chemical, Physical, and Technical Calculations. {^U^^ivSl^' 

be decided until chemically pure titanium has been ob- 
tained. 2. The assumption that this redu^on*prodod 
consists exclusively of a lower stage of oxidation of tita- 
nium is opposed to the following fads:^<i. No such 
lower oxides of titanium have been hitherto isolated. 
b. The melting-point of titanium lies at a very high tem- 
perature, as may be learnt from the difficulty of alloying 
It with copper. 3. There are probably two titaoinm 
nitrides. The higher, indigo-blue nitride, passes at a 
white* heat into the lower and more stable bronxe-yellow 
nitride. 4. The higher nitride can be easily converted 
into a crystalline titanium sulphide by heating to redness 
with sulphur in a current of hydrogen. 5. A '* titaninm 
chloroform ** has not yet proved obtainable. In this 
respedt titanium behaves like tin. On the aAion of dry 
hydrochloric acid upon elementary titanium there arises 
achlorinised produd, not volatile. It must be kept in 
mind that this readion may depend upon the presence of 
a titanium hydroxide or a solid titanium hydride in the 
elementary titanium. 

The Influence of Hydration upon Solubility. — N. 
Kumakow.— This paper requires the two accompanying 
diagrams. 

The Solutions of Qreen Chromium Chloride^ 
CrCl3.6HaO. — A. Piccini. -^ The inferences following 
from the author's results are :— Silver fluoride has, in re- 
ference to the green chromium chloride, the property of 
precipitating that portion of chlorine— or causing it to 
assume the fnndion of an ion— which is not precipitable 
by the other silver salts, and in their presence does not 
ad as an ion. In solutions in which the method of the 
boiling-point indicates little or no dissociation of the green 
chromium chloride, all the chlorine is precipitate by 
silver nitrate, whilst in solutions in which dissociation 
ensues the precipitation is only partial. The solutions of 
green chromium chloride in methylic alcohol take, in pre- 
sence of silver nitrate, an intermediate position between 
the watery solutions and those on ethyltc alcohol. 

On some New Methods of obtaining Platinous 
Chlorides, and on the Probable Sxistence of Plati- 
num Subchloride.— M. Carey Lea. 

The Caesium Double Chlorides, Bromides, and 
Iodides, with Cobalt and Nickel.— G. F. Campbell. 

It is understood that these two papers have appeared 
also in the English languages. 



tel free, and the O combines with C, forming CO. 

One kg. steam of xoo* (373® N absol.) consists of 1/9 kg. 
H and 8/9 kg. O, and forms when passed through glowing 
carbon, and the produd cooled down to o^ N, at at mo. 

a bene density; x/9 kg. « 56/4^ cbm. H ; 8/9 kg. O com. 
les with 6/9 kg. C, forming 14/9 kg. « 56-45 cbm. CO ; con- 
sequently X kg. steam and 6/9 kg. C form 15/9 kg. «! 12/45 
cbm. water gas of o^ N (273^ N absol.) and atm. density ; 
consequently* 

I kg. water gas » 1x2/75 cbm., and x cbm. » 75/xia kg* 

s kg. water gas contains 3/f kg. steam + 2/5 kg. C. 

1 1^. water gas contains x7x5 kg. H+X4/X5 CO ; -> 56*75 

cbm. H+ 56*75 cbm. CO. 
I cbm. water gas contains i cbm. H + i cbm. CO ; »5/ix2 

kg. H+ 5/8 kg. CO. 
Prodoaion of i kg. of water gas of 273*" N. absol. 
requiies:— 

3/5 ^' o^ liquid water of 273* N absol. dis. 
solved into H and O by the united 
adion of heat and the chemical affinity 
of carbon, absorbs, separating x/x5 kg. 
H from O, x/15 X X7340 cal •1x56 calors. 

9/5 kg. solid carbon to gasify absorbs 

«/lX33oa|cal -X3at^ tt 



a/5 kg. C, burnt with 8/X5 kg, O. to form 
' • " 8^x5: 



^77 f 



14/15 ^K' CO, produces 8/X5 x 4335 cal. » 23 12 „ 

s kg. water gas requires for its produdion a x65^ „ 
I cbm. of atm. density requires x65f X75/112 kg. a 

exiofil calors. 

Combustion of i kg. of Water Gas, 

For x/x5 kg. H is required 8/X5 
n 14/15 .. CO „ 8/15 



kg o) '^''5 kg. O. which 
nr produces 4624 
" ^) calors. 



Combustion of s cbm. Water Oas. 

n.Hi 
•» i/a M CO 



For x/2 cbm. HJsrequired x/4cbm. o| "^^ce^; ^^S 



calors. 



(To be oootinasd). 



% Valdesiarinde, Copenhacen, V. 
July a;, r 



.1895. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NOTS.— All degrees of temperature are Centifrade onlets otherwise 
eipresied. 

Zeituhrtfl fiir Ancrgamsche Chtmie^ 
Vol. viii., Parts x and 2. 

The Atomic and Molecular Solution Volumes.— 
J. Traube. -* This extensive paper has been already 
noticed. 

The Foundations of a New System of the Ele- 
ment8.»J. Traube.— Already inserted. 

Critical Studies on the Chemistry of Titanium. 
— B. A. Schneider. — The results of the above studies 
may be briefly summarised as— x. The produa obtained 
from potassium titano-fluoride by redudtion with sodium 
in a current of hydrogen contains not only oxygen, but 
also hydrogen. Whether we have here a titanium by- 
dride» hydroxide, or a case of simple absorption, cannot 



ACCTONB — Answering all requirements. 

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ZBOKr-A-GIO— Cryat. and powder. 

- CI1*IRIO~Cryst. made in earthenware. 
— — <jf A T.T. Tn—Prom best Chioeee galls, pure. 

S^XilGYIjIC-By Kolbe'a process. 

I'-A-IEsT^ETIC—Po'' Pharmacy mod the Arts. 

LIQUID CHLORINE 

(Compreued in steel cylinders). 

FORMALIN (40?^ CHjO)— Antiseptic and Preservative. 

POTASS. PBRMANQANATE-Cryst., large and small. 

SULPHOCYANIDB OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIG-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THE ARTS 



Wholesale Agents— 

A. & M. ZIMMERMANN, 

6 a 7, CROSS LANE UONDON. E.G. 



CWUCALNlWtil 

8«pt.ao,i89S. f 



British Association. — The President's Address. 



139 



THE CHEMICAL NEWS. 

Vol. LXXII., No. 1869. 



BRITISH ASSOCIATION 

FOR THB 

ADVANCEMENT OF SCIENCE. 

Ipswich, 1895. 

INAUGURAL ADDRESS OF THB PRESIDENT, 

Sir Douglas Qalton, K.C.B., D.C.L., F.R.S. 

(Condoded from p. 136). 

Imflurncb op Intbrcommunication afforded by 

British Association on Scibnce Progress. 
Thb advances in engineering have prodaced the steam- 
engine, the railway, the telegraph, as well as our engines 
of war, may be said to be the result of commercial enter- 
prise rendered possible onlv by the advances which have 
taken place in the several branches of science since 1831. 
Having regard to the intimate relations which the several 
sciences bear to each other, it is abundantly clear that 
BBQch of this progress could not have taken place in the 
past, nor could further progress take place in the future, 
without intercommunication between the students of 
different branches of science. 

The founders of the British Association based its claims 
to ntUity upon the power it afforded for this intercommu- 
BicatioB. Mr. Vernon Harcourt (the uncle of your 
present General Secretary), in the address he delivered 
m 1832, said :^'* How feeble is man for any purpose 
when he stands alone— how strong when united with 
other roenl" • . . 

I claim for the British Association that it has fulfilled 
the ofejeas of its founders, that it has had a large share 
io promoting intercommunication and combination. 

Our meetmgs have been successful because they have 
maintained the true principles of scientific investigation. 
We have been able to secure the continued presence and 
concurrence of the master-spirits of science. They have 
been willing to sacrifice their leisure, and to promote the 
welfare of the Association, because the meetings have 
mfforded them the means of advancing the sciences to 
which they are attached. 

The Association has, moreover, justified the views of 
its founders in promoting intercourse between the pur- 
suers of science, both at home and abroad, in a manner 
which is afforded by no other agency. 

The weekly and sessional reunions of the Royal 
Society, and the annual soirits of other scientific socie- 
ties, promote this intercourse to some extent ; but the 
British Association presents to the young student, during 
iu week of meetings, easy and continuous social oppor- 
tunities for making the acquaintance of leaders in science, 
and thereby obtaining their direding influence. 

It thus encourages, in the first place, opportunities of 
combination, but, what is equally important, it gives at 
the same time material assistance to the investigators 
whom it thus brinn together. 

The reports on the state of science at the present time, 
MB they appear in the last volume of our Proeudings, oc> 
copy the same important position, as records of science 
progress, as that occupied by those Reports in our earlier 
We exhibit no symptom of decay. 



Scibncb in Gbrmany postered by the State and 
Municipalities. 
Our neighbours and rivals rely largely upon the guidance 
of the State for the promotion of both science teaching 



and of research. In Germany the foundations of tech- 
nical and industrial training are laid in the Realschulen, 
and supplemented by the Higher Technical Schools. In 
Berlin that splendid institution, the Royal Technical 
High School, casts into the shade the facilities for edu- 
cation in the various Polytechnics which we are now 
establishing in London. Moreover, it assists the prac- 
tical workman by a branch department, which is available 
to the public for testing building materials, metals, paper, 
oil, and other matters. The standards of all weights and 
measures used in trade can be purchased from or tested 
by the Government Department for Weights and 
Measures. 

For developing pure scientific research and for pro* 
moting new applications of science to industrial purposes 
the German Government at the instance of von Helm- 
holts, and aided by the munificence of Werner von 
Siemens, created the Physikalische Technische Reichan* 
suit at Charlottenburg. 

This establishment consists of two divisions. The 
first is charged with pore research, and is at the present 
time engaged in various thermal, optical, and eleArical, 
and other physical investigations. The second branch 
is emplo3red in operations of delicate standardisiuff to 
assist the wants of research students—for instance, dila- 
tation, eleArical resistances, eledric and other forms of 
light, pressure gauges, recording instruments, thermo- 
meters, pyrometers, tuning-forks, glass, oil-testing appa- 
ratus, viscosity of glycerin, ftc. 

Dr. Kohlrausch succeeded Helmholts as president, and 
takes charge of the first division. Professor Hagen, the 
diredor under him, has charge of the second division. A 
professor is in charge of each of the several sub-depart- 
ments. Under these are various subordinate posts, held 
by youneer men, seleded for previous valuable work, and 
usually lor a limited time. 

The general supervision is under a Council, consisting 
of a president, who is a Privy Councillor, and twenty-four 
members, including the president and diredor of the 
Reichsanstalt ; of the other members about ten are pro- 
fessors or heads of physical and astronomical observato- 
ries conneded with the principal universities in Germany. 
Three are seleded from leading firms in Germany repre- 
senting mechanical, optical, and eledric science, and the 
remainder are principal scientific officials conneded with 
the Departments of War and Marine, the Royal Observa- 
tory at Potsdam, and the Royal Commission for Weights 
and Measures. 

This Council meets in the winter, for such time as msf 
be necessary, for examining the research work done in the 
first division during the previous year, and for laying down: 
the scheme for research for the ensuing year ; as well as 
for suggesting any requisite improvements in the second 
division. As a consequence of the position which 
science occupies in connedion with the State in Conti- 
nental countries, the services of those who have distin- 
guished themselves either in the advancement or in the 
application of science are recognised by the award of 
honours ; and thus the feeling for science is encouraged 
throughout the nation. 

Assistance to Scientific Rbbbaech in Qexat 

Britain. 
Great Britain maintained for a long time a leading 
position among the nations of the world by virtue of the 
excellence and accuracy of its workmanship, the result 
of individual energy; but the progress of mechanical 
science has made accuracy of workmanship the common 
property of all nations of the world. Our records show 
that hitherto, in its efforts to maintain its position by the 
application of science and the prosecution of research, 
England has made marvellous advances by means of 
voluntary effort, illustrated by the splendid munificence 
of such men as Gassiot, Joseph Whitworth, James Msson, 
and Ludwig Mond; and, whilst the increasing field of 
scientific research compels us occasionally to seek for 



140 



British Association. — The Presidents Address. 



f Cbbhical Niwt« 



Qovernment asBistance, it would be unfortunate if by any 
change voluntary effort were fettered by State control. 

The following are the principal voluntary agencies 
which help forward scientific research in this countfy :~ 
The Donation Fund of the Royal Society, derived from 
its surplus income. The British Association has contri- 
buted /6o,ooo to aid research since its formation. The 
Royal Institution, founded in the last century, by Count 
Rumford, for the promotion of research, has assisted the 
investigations of Davy, of Young, of Faraday, of Frank- 
land, of Tyndall, of Dewar, and of Rayleigh. The City 
Companies assist scientific research and foster scientific 
education both by dired contributions and through the 
City and Guilds Institute. The Commissioners of the 
Exhibition of X85X devote ;(6ooo annually to science 
research scholarships, to enable students who have passed 
through a college curriculum and have given evidence of 
capacity for original research to continue the prosecution 
of science, with a view to its advance or to its applica- 
tion to the industries of the country. Several scientific 
societies have promoted dired research, each in their own 
branch of science, out of ther surplus income ; and every 
scientific society largely assists research by the publica- 
tion, not only of its own proceedings, but often of the 
work going on abroad in the branch of science which it 
represents. 

The growing abundance of matter year by vear increases 
the burden thus thrown on their finances, and the Treasury 
has recentl}r granted to the Royal Society £1000 a year, 
to be spent in aid of the publication of scientific papers 
not necessarily limited to those of that Society. 

The Royal Society has long felt the importance to sci- 
entific research of a catalogue of all papers and publica- 
tions relating to pure and applied science, arranged 
systematically both as to authors' names and as to subjed 
treated, and the Society has been engaged for some time 
upon a catalogue of that nature. But the daily increasing 
magnitude of these publications, coupled with the neces- 
sity of issuing the catalogue with adequate promptitude 
and at appropriate intervals, renders it a task which could 
only be performed under International co-operation. The 
officers of the Royal Society have therefore appealed to 
the Government to urge Foreign Governments to send 
delegates to a Conference to be held next July to discuss 
the desirabiilty and the scope of such a catalogue, and 
the possibility of preparing it. 

The universities and colleges distributed over the 
country, besides their fundion of teaching, are large pro- 
moters of research, and their voluntary exertions are aided 
in some cases by contributions from Farliament in allevi- 
ation of their expenses. 

Qertain executive departments of the Government carry 
on research for their own purposes, which in that resped 
nay be classed as voluntary. The Admiralty maintains 
the Greenwich Observatory, the Hydrographical Depart- 
ment, and various experimental services ; and the War 
Office maintains its numerous scientific departments. 
The Treasury maintains a valuable chemical laboratory 
for Inland Revenue, Customs, and agricultural purposes. 
The Science and Art Department maintains the Royal 
College of Science, for the education of teachers and 
students from elementary schools ; it allows the scientific 
apparatus in the National Museum to be used for research 
purposes by the professors. The Solar Physics Committee, 
which has carried on numerous researches in solar physics, 
was appointed by and is responsible to this Department. 
The Department also administers the Sir Joseph Whit- 
worth engineering research scholarships. Other scientific 
departments of the Government are aids to research, as, 
for instance, the Ordnance and the Geological Surveys, 
the Royal Mint, the Natural History Museum, Kew 
Gardens, and other lesser establishments in Scotland and 
Ireland ; to which may be added, to some extent, the 
Standards Depaitment of the Board of Trade, as well as 
municipal museums, which are gradually spreading over 
the country. 



For dired assistance to voluntary effort the Treasury 
contributes £4000 a year to the Royal Society for the 
promotion of research, which is administered under a 
board whose members represent all branches of Science. 
The Treasury, moreover, contributes to marine biological 
observatories, and in recent years has defrayed the cost 
of various expeditions for biological and astronomical 
research, which in the case of the Challtngir expedition 
involved very large sums of money. 

In addition to these dired aids to science, Parliaoieot, 
under the Local Taxation Ad, handed over to the County 
Councils a sum, which amounted in the year 1893 to 
£615,000, to be expended on technical education. In 
many country distrids, so far as the advancement of real 
scientific technical progress in the nation is concerned, 
much of this money has been wasted for want of know- 
ledge. And whilst it cannot be said that the Government 
or Parliament have been indifferent to the promotion of 
scientific education and research, it is a source of regret 
that the Government did not devote some small portion 
of this magnificent gift to affording an objed-lesson to 
County Councils in the application of science to technical 
instrudion, which would have suggested the principles 
which would most usefully guide them in the expenditure 
of this public money. 

Government assistance to science has been based 
mainly on the principle of helping voluntary effort. The 
Kew Observatory was initiated as a scientinc observatory 
by the British Association. It is now supported by the 
Gassiot trust fund, and managed by the Kew Observatory 
Committee of the Royal Society. Observations on mag- 
netism, on meteorology, and the record of sun-spots, as 
well as experiments upon new instruments for assisting 
meteorological, therroometrical, and photographic pur- 
poses, are being carried on there. The Committee has 
also arranged for the verification of scientific measuring 
instruments, the rating of chronometers, the testing ot 
lenses and of other scientific apparatus. This institution 
carries on to a limited extent some small portion of the 
class of work done in Germany by that magnificent insti- 
tution, the Reichsanstalt at Charlottenburg, but iu 
development is fettered by want of funds. British 
students of science are compelled to resort to Berlin and 
Paris when they require to compare their more delicate 
instruments and apparatus with recognised standards. 
There could scarcely be a more advantageous addition to 
the assistance which Government now gives to science 
than for it to allot a substantial annual sum to the exten- 
sion of the Kew Observatory, in order to develop it on 
the model of the Reichsanstalt. It might advantageously 
retain its connedion with the Royal Society, under a 
Committee of Management representative of the various 
branches of science concerned, and of all parts of Great 
Britain. 

Conclusion. 

The various agencies for scientific education have pro- 
duced numerous students admirably qualified to pursue 
research; and at the same time almost every field of 
industry presents openings for improvement through the 
development of scientific methods. For instance, agricul- 
tural operations alone offer openings for research to the 
biologist, the chemist, the physicist, the geologist, the 
engineer, which have hitherto been largely overlooked. If 
students do not easily find employment, it is chiefly attri- 
butable to a want of appreciation for science in the nation 
at large. 

This want of appreciation appears to arise from the 
fad that those who nearly half a century ago direded the 
movement of national education were trained in early life 
in the universities, in which the value of scientific methods 
was not at that time fully recognised. Hence our elemen- 
tary, and even our secondary and great public scbools« 
negleded for a long time to encourage the spirit of investi* 
gation which develops originality. This defed is 
diminishing daily. 

There is, however, a more intangible cause which ma^ 



y^- 



CSBMICAL NtWt, t 

Sept. ao, 1893. f 



British Association. — Pro/. Meldola's Address. 



141 



have had lailaence on the want of appreciation of science 
by the nation. The Government, which largely profits 
by science, aids it with money, but it has done very little 
to develop the national appreciation for science by recog- 
nising that its leaders are worthy of honours conferred by 
the State. Science is not fashionable, and science stu- 
dents— upon whoee efforts our progress as a nation so 
largely depends— have not received the same measure of 
recognition which the State awards to services rendered 
by its own officials, by politicians, and by the Army and 
\>y the Navy, whose success in future wart will largely 
depend on the effedive applications of science. 

The Reports of the British Association afford a complete 
chrooide of the gradual growth of scientific knowledge 
since 1831. They show that the Association has fulfilled 
the objeAs of its founders in promoting and disseminating 
a knowledge of science throughout the nation. 

The growing connexion between the sciences places 
our annual meeting in the position of an arena where 
representatives of the different sciences have the oppor- 
tunity of criticising new discoveries and testing the value 
of fresh proposals, and the Presidential and Sedional 
Addresses operate as an annual stock-taking of progress 
in the several branches of science represented in the Sec- 
tions. Bvery year the field of usefulness of the Associa- 
tion is widening. For, whether with the geologist we 
seek to write the history of the crust of the earth, or with 
the biologist to trace out the evolution of its inhabitants, 
or whether with the astronomer, the chemist, and the 
physicist we endeavour to unravel the constitution of the 
sun and the planets or the genesis of the nebulae and stars 
which make up the universe, on every side we find our- 
selves surrounded by mysuries which await solution. We 
are only at the beginning of work. 

I have, therefore, full confidence that the future records 
of the British Association will chronicle a still greater 
progress than that already achieved, and that the British 
nation will maintain its leading position amongst the 
nations of the world, if it will energetically continue its 
voluntarv efforts to promote research, supplemented by 
that additional help from the Government, which ought 
never to be withheld when a clear case of scientific utility 
has been established. 



ADDRESS TO THE CHEMICAL SECTION 

OP THE 

BRITISH ASSOCIATION. 
Ipswich, 1895. 

By Prol. RAPHAEL IIBLDOLA, F.R.S., F.I.C., Foa. See. C.S., 
Prceid«ot of the Seaioo. 

The State op Chemical Science in 1851. 
In order to estimate the progress of chemical science 
since the year 1851, when the British Association last 
met in this town, it will be of interest for us to endeavour 
to place ourselves in the position of those who took part 
in the proceedings of Se^ion B on that occasion. Per- 
haps the best way of performing this retrograde feat will 
be to confront the fundamental doArines of modem 
chemistry with the state of chemical theory at that 
period, because at any point in the history of a science 
the theoretical conceptions in vogue — whether these con- 
ceptions have survived to the present time or not— may 
be taken as the abstrad sommation of the fads, i.#., of 
the real and tangible knowledge existing at the period 
chosen as the standard of reference. 

Without going too far back in time I may remind you 
that in 18 11 the atomic theory of the chemists was 
grafted on to the kindred science of physics through the 
enunciation of the law associated with the name of 
Avogadro di Qoaregna. The rationalising of this law 
had been accomplished in 1845 ; but the kinetic theorv of 
gascSf which had been foreshadowed by D. Bernoulli in 



X738, and in later times by Herapath, Joule, and Krdnig, 
lay buried in the archives of the Royal Society until re« 
cently unearthed by Lord Rayleigh and given to the world 
in 1892 under the authorship of Waterston, the legitimate 
discoverer. The later developments of this theory did 
not take place till after the last Ipswich meeting, vis., 
in 1857— 1862, by Clausius, and by Clerk Maxwell in 
1860—1867. Thus the kinetic theory of gases of the 
physicists had not in 1851 acquired the full significance 
for chemists which it now possesses ; the hypothesis of 
Avogadro was available, analogous conceptions had been 
advanced by Davy in 1812, and by Ampere in 18x4; but 
no substantial chemical reasons for its adoption were ad- 
duced until the year 1846, when Laurent published his 
work on the law of even numbers of atoms and the 
nature of the elements in the free state (i4fifi. Chim, Pky$, 
[3],xviii., 266). 

The so called <* New Chemistry," with which students 
of the present time are familiar, was, in fad, being evolved 
about the period when the British Association last assem- 
bled at Ipswich ; but it was not till some years later, and 
then chiefly through the writings of Laurent and Ger« 
hardt, that the modern views became accepted. It is of 
interest to note in passing that the nomenclature of 
organic compounds formed the subje^ of a report by 
Dr. Daubeny at that meeting, in which he says :—** It 
has struck me as a matter of surprise that none of the 
British treatises on Chemistry with which I am acquainted 
should contain any rules to guide us, either in affixing 
names to substances newly discovered or in divining the 
nature and relations of bodies from the appellations 
attached to them. Nor do I find this deficiency supplied 
in a manner which to me appears satisfa^ory when 1 lam 
to the writings of Continental chemisU.'* In a sobeo- 
quent portion of the report Dr. Daubeny adds :— ** No 
name ought, for the sake of convenience, to exceed in 
length six or seven syllables." I am afraid the require- 
ments of modern organic chemistry have not enabled us 
to comply with this condition. 

Among other physical discoveries which have exerted 
an important influence on chemical theory, the law of 
Dulong and Petit, indicating the relationship between 
specific heat and atomic weight, had been announced in 
18 19, had been subsequently extended to compounds by 
Neumann, and still later had been placed upon a sure 
basis by the classical researches of Regnanlt in 1839. 
But here, again, it was not till after 1851 that Canttixsaro 
(1858) gave this law the importance which it now possesses 
in conneaion with the determination of atomic weights. 
Thermo-chemistry as a distinA branch of our science mav 
also be considered to have arisen since 1851, althongh 
the foundations were laid before this period by the work 
of Favre and Silbermann, Andrews, Graham, and espe« 
cially Hess, whose important generalisation was announced 
in 1840, and whose claim to just recognition in the his* 
tory of physical chemistry has been ably advocated in 
recent times by Ostwald. But the elaboration of thermo* 
chemical fads and views in the light of the dynamical 
theory of heat was first commenced in 1853 by Julius 
Thomsen, and has since been carried on concurrently 
with the work of Berthelot in the same field which the 
latter investigator entered in 1865. Eledro-chemistrv in 
185 X was in an equally rudimentary condition. Davy bad 

Sublished his eledro-chemical theory in x8o7, and in x8x2 
lerselias had pot forward those views on eledric affinity 
which became the basis of bis dualistic system of formu* 
lation. In 1833 Faraday announced his famous law of 
elcaro-chemical equivalence, which gave a fatal blow to 
the conception of Berzeltus, and which later (X839— X840) 
was made use of by Daniell in order to show the untena* 
bility of the dualistic system. By X85X the views of 
Berielius had been abandoned, and, so far as chemical 
theory is concerned, the whole subjed may be considered 
to have been in abeyance at that time. It is of interest 
to note, however, that in that year Williamson advanced, 
on quite distind grotmds, his now well-known theory ojf 



Uritish Association.— Prof. Meldota's Address. {*'"se'Ji:^?4J*' 



«4>» 

HlUMilv iMl»ri')iiinK« between molecules, which theory io a 
fiHii* «Nl<>fMl«(i form w«t developed independently from 
llm j'hyiiUiil ftide and applied to eledrolytes byClausius 
In in57. The modern theory of eledrolysis associated 
with Ihn names of Arrhenius, van *t HofT, and Ostwald, 
In of (omparatively recent growth. It appears that Hit. 
lorf, In lii'j^t was the first to point out the relationship 
between eledtrolytic condudtivity and chemical adlivity, 
this same author as far back as 1856 having combated 
the prevailing view that the eledlric current during eledlro- 
ivsia does the work of overcoming the affinities of the ions. 
Arrhsnlus formulated his theory of eledlrolytic dissocia- 
tion In 1887^ Planck having almost simultaneously arrived 
at similar views on other grounds. 

Closely connedted with cleArolysis is the question of 
tha constitution of solutions, and here again a convergence 
of work from several dlstin^ fields has led to the creation 
of a new branch of physical chemistry which may be 
considered a modern growth. The relationship between 
the strength of a solution and its freexing-point had been 
discovcrtd by DIagden towards the end of the last 
century, but in 1851 chemists had no notion that this 
observation would have any influence on the future deve- 
lopment of their science. Another decade elapsed before 
the law was rc'dlscovcred bv RudotfT (1861), and ten years 
later was fufther elaboratea by de Copper. Raoult pub- 
lished his first work on the freosing-point of solutions in 
f N8s, and two years later the relationship between osmotic 

CtenMUre and the lowering of (reeiing-point was established 
y ft. de Vrlfs, who first approached the subieA as aphy* 
llologlsli through obstrvAiions on the cell-contents of 
llvlriK plantSi As the work done in connexion with 
tfArttdllc preniure has had such an important influence on 
the " dlssuciatloh *' theory of solutions, it will be of inte- 
rest lu rtote that at the last Ipswich meeting Thomas 
(irsham msde a communication on liquid diffusion, in 
Which he "gave a view of some of the unpublished results, 
tu Ascertain whethei solutions of saline bodies had a power 
rtf dltrunlun emung liquids, especially water.** In 1877 
PrefTer, who, like de Vrivs, entered the field from the 
botanical physiological side, succeeded in effe^ing the 
Htiesurviiieiit of usmoilc pressure. Ten years later 
vart 'I Iti'fT rolliiulslsd the modern dissociation theory of 
sifhriliih by ftJ«plyli^K 1^' dissolved substances the laws of 
|1i<ylf« (Uy iiUHMKi*. and Avogadro, the law of osmotic 
lUfiitMriFi artil H«i«»ult'« law conneding the depression of 
llHc^lMg pMiMt wilh molecular weight, thus laying the 
iMurhiaiiMM Mf fi iliK'lilne which, whether destined to sur- 
VUf* \\\ M« pissoiil loiin or not, has certainly exerted a 
|i»iHf h<ilM''it»*> »'H M^niemporary chemical thought. 

r»«Hftl*l**»i hMtl)oit Iho »tate of knowledge in 1851 con- 
i.»;tMhu{ ftu^h It'Milloo principles as dissociation orthermo- 
ivaio, iM4«ii h*'UhI) ttiul chemical equilibrium. Abnormal 
^.^^t.i.t >lMt*iMiiii hfiil ht^pn observed by Avogadro in 1811, 
^\\^\ I I n.jio 1^ 1N14. Qrove had dissociated water 
S^Y'^m 1^1 iii^fit l^t ini7, but the first grest advance was 
liuttv I (ail ^^iii \M'\ ity Hsinte-Claire Deville, from whose 
^ii«k 4{4S liHMH^li I our existing knowledge of this sub- 
\h^ i m^i^ ^'lil Mill ihe application of this principle to 
li^^kiu ihki ^4»tt ^1 abnormal vapour density was made 
4|j \^\k V^ ^"y\u K^kuiO, and Canniisaro, almost simul- 
iiiHt'i'if^i I I'l^^ utiHu^sly enough, this explanation was 
tiT^i^^Uffi ^^ livutt*. hiiiuttlf. The subsequent stages are 
fti*mt4* Ml lUM'ttaiH iMtoiory. The current views on mass 
4Al'4fi V^istu Mi««li" l«v^ed» as is well known,|by BerthoUet 
iD M« " ^lAii^iif' * uimique,** published in 1803, but no 
i^f»it 4(4t4Mvc li€x\ i'Lto made when the British Associa- 
imn Um tMU iriH t ho sublcCl first began to assume a 
■iUiit^lliil<\«« Mi'«^ Uuough the rtpstarches of Bunsen and 
ntbiii ill lft,vi 41) I was much advAnctd by Gladstone in 
|A|. fciiJ ^) H^fk iui And U«aoit a ypat later, QoKlberg 
4^^rWuf* ffiMiilud |h«M vUavivil work on thia subjec\ 

fatiMii iliikiPi^ Mil A)>)««A( Iho advancss msile »inco 

t»hi«t^'^ b'iiM^r^ ih.4l iti»! \Ou«)p iiit)«jc»i*^ o( nprCliuin 

,,- wi.uli biui^aoiii ft^i,.t(»o iMiu iirUnvMtftliip with 



t astronomy, has been called into existence since that date. 
I The celebrated work of Bunsen and Kirchhoff was not 
; published till 1859. Neither can I refrain from reminding 
you that the coal-tar colour industry, with which I have 
been to a small extent conneded, was started into adivity 
by Perkin's discovery of mauve in 1856 ; the readion of 
this industry on the development of organic chemistry ia 
now too well known to require further mention. In that 
diredion also which brings chemistry into relationship 
with biology, the progress has been so great that it is not 
going beyond the fad to stat that a new science has been 
created. Pasteur began his studies on fermentation in 
1857, and out of that work has arisen the science of 
baderiology, with its multifarious and far-reaching conae- 
qoences. As this chapter of chemical history forms the 
aubjed of one of the evening discourses at the present 
meeting, it is unnecessary to dwell further upon it now. 
One other generalisation may be chronicled among the 
great developments achieved since 1851. I refer to the 
periodic law conneding the atomic weights of the che- 
mical elements with their physical and chemical proper- 
ties. Attempts to establish numerical relationships in 
the case of isolated groups of elements had been made 
by Ddbereiner in 18x7, by Qmelin in 1826, and again by 
Ddbereiner in 1829. The triad system of grouping was 
furtser developed by Dumas in 185 1. I am informed by 
Dr. Gladstone that at the last Ipswich meeting Dumas' 
speculations in this diredion excited much interest. All 
the later steps of importance have, however, been made 
since that time, viz., by de Chancourtois in 1862, the 
*' law of odaves " by Newlands in 1864, the periodic law 
by Meodeleeff, and almost contemporaneously by Lothar 
Meyer, in 1869. 

I have been tempted into giving this necessarily frag- 
mentary and possibly tedious historical sketch because it 
is approaching half a century aince the British Associa- 
tion visited this town, and the opportunity ^ seemed 
favourable for going through that process which \n com- 
mercial affairs ia called "taking stock." The result 
speaks for itself. Our stodenu of the present time who 
are nourished intelledoally by these dodrinea should be 
made to realise how rapid has been their development. 
The pioneers of our science on whose shoulders we stand 
— and many of whom are happily still among ua— will 
derive satisfadion from the retroeped, and will admit 
that their labours hare borne goodly fruit. It is not, 
however, simply for the purpose of recording this enor- 
mous progress that I have ventured to assume the office 
of stock-taker. The jrear 1851 may be regarded as occur- 
ring towards the close of one epoch and the dawn of a 
new era in chemical history. Consider broadly the state 
of organic chemistry at that time. There ia no occasion 
for going into detail, even if time admitted, because our 
literature has recently been enriched by the concise and 
excellent historical worka of Schorlemmer, and of Ernst 
von Meyer. It will suffice to mention that the work and 
writings of Liebig, Berzelius, Wohler, Dumas, Gay- 
Lussac, Bunsen, and otben, had given us the leading 
ideas of isomerism, substitution, compound radicles, and 
types. Wurtx and Hofmann had just discovered the 
organic ammonias; Williamson that same year made 
known his celebrated work on the ethers ; and Gerhardt 
discovered the acid anhydrides a year later. The newer 
theory of types was undergoing development by Gerhardt 
and his followers; the mature results were published in 
the fourth volume of the *' Trait6 de Chimie '* in 1856. 
In this country the theory was much advanced by the 
writings of OdUng and Williamson. 

Subsequent DsvsLonnNT op Cbbmistry axjoko 
Two Lines. 

The new era which waa dawning upon na in 185 1 waa 
that of strudural or constitoticnal chemistry, based on 
the doifltine of the valency of the atoms. It is well known 
that this conception was broached by Frankland in 1852, 
at the tc^uU of h.s investigations on the organo* metal lie 



CRKinCAL KiWt, I 

Sept. M, 1895. J 



British Association. — Prof. Meldola^s Address. 



143 



compounds. But it was not till 1858 that Kekul6, who 
bad previously done much to develop the theory of types, 
and 6onper, almost simultaneously, recognised the quad- 
f ivalent charader of carbon. To attempt to give any* 
thing approaching an adequate notion cf the subsequent 
influence of this idea on the progress of organic che- 
mtsuy would be tantamount to reviewing the present 
condition of that subjed. I imagine that no conception 
more prolific of results has ever been introduced into any 
department of science. If we glance back along the 
stream it will be seen that shortly after the last meeting 
here the course of discovery began to concentrate itself 
into two channels. In one we now find the results of 
the confluent labours of those who have regarded our 
science from its physical side. In the other channel is 
flowing the tide of discovery arising from the valency 
doArine and its extension to the strudure of chemical 
molecules. The two channels are at present fairly paral- 
lel and not far apart ; an occasional explorer endeavours 
now and again to make a cross-cot so as to put the 
streams into communication. The currents in both are 
ninning very rapidly, and the worker who has embarked 
on one or the other finds himself hurried along at such a 
pace that there is hardly breathing time to step ashore 
and see what his neighbours are doing. It speaks well 
for the fertility of the conception of valency that the 
current in this channel is flowing with unabated vigour, 
although its catchment area— to pursue the metaphor— is 
by 00 means so extensive as that of the neighbouring 
stream. 

The modern tendency to specialisation, which is a ne* 
cessity arising from the large number of workers and the 
rapid multiplication of results, is apparently in the two 
direAions indicated. We have one class of workers deal- 
ing with the physics of matter in relation to general 
chemical properties, and another class of investigators 
concerning themselves with the special properties of indi- 
vidoal compounds and classes of compounds— with atomic 
idiosjrncracies. The workers of one class are differenti. 
atiog while their colleagues are integrating. It would be 
nothing less than unscientific to institute a comparison 
between the relative merits of the two methods ; both are 
necessary for the development of our science. All me- 
thods of attacking the unknown are equally welcomed. 
In some cases physical methods are available ; in other 
cases purely chemical methods have alone been found of 
Dse. There is no antagonism, but co-operation. If the 
results of the two methods are sometimes at variance it 
is simply because we have not known how to interpret 
tbem. The physical chemist has adopted the results of 
the application of chemical methods of determining 
** constitution," and is endeavouring to furnish us with 
new weapons for attacking this same problem. The che- 
mist who is seeking to unravel the architedure of mole- 
cqIcs is dependent at the outset upon physical methods of 
determining the relative weights of his molecules. The 
wockcr who is bringing about new atomic groupings is 
furnishing material for the further development of gene- 
ralisations from which new methods applicable to the 
problem of chemical strudure may again be evolved. 
The physical chemist sometimes, from the broadness of 
bis view, is apt to overlook or to minimise the importance 
of chemical individuality. On the other hand, the chemist 
wbo is studying the numberless potentialities of combina- 
tion resident in the atoms, and who has grasped to the 
full extent their marvellous individualities, is equally 
liable to forget that there are conneding relationships as 
well as specific differences in the properties of elements 
and compounds. These are but the mental traits — the 
unconscious bias engendered by the necessary specialisa- 
tion of work to which I have referred, and which is 
observable in every department of scientific labour. 

Ths Pkbsknt Stats of Strxjctxjral Chemistry. 
The success attending the application of the doArine 
of valency to the compounds of carbon has helped its 



extension to all compounds formed by other elements, and 
the student of the present day is taught to use strudnral 
formulae as the A B C of his science. It is, I think, gene* 
rally recognised among chemists that this dodrine in its 
present state is empirical, but it does not appear to me 
that this point is sufficiently insisted upon in chemical 
teaching. I do not mean to assert that for the last thirty 
years chemists have been pursuing a phantom ; neither do 
I think that we should be justified in applying to this 
dodrine the words applied to its iorerunner, the ** types" 
of Gerhardt, by Lothar Meyer, who says that these 
" have rendered gre:.t service in the development of the 
science, but they can only be regarded as a part of the 
scaff^olding which was removed when the ere&ion of the 
system of organic chemistry had made sufficient progress 
to be able to dispense with it " (" Modern Theories of 
Chemistry,*' p. 194). It appears to me, on the contrary* 
that there is a physical reality underlying the conception 
of valency, if for no other reason because of the con- 
formability of this property of the atoms to the periodic 
law. But the dodrine as it stands is empirical, in so far 
that it is only representative and not explanatory. Frank- 
land and Kekul6 have given us a great truth, but its very 
success is now making it more and more obvious that it 
is a truth which is pressing for further development from 
the physical side. If we are asked why CO exists, and 
why CHa and CCI2 do not, together with innumerable 
similar questions which the inquisitive mind will raise, we 
get no light from this dodrme. If any over-sanguine 
disciple goes so far as to assert that all the possible com- 
pounds of the elements indicated by their valency are 
capable of existence, and will sooner or later be prepared, 
he will, I imagine, find himself rapidly travelling away 
from the region of fad. 

There is something to be reckoned with besides valency. 
The one great desideratum of modern chemistry is un« 
questionably a physical or mechanical interpretation of 
the combining capacities rf the atoms. Attempts at the 
construdion of such theories have been made, but thus 
far only in a tentative way, and these views cannot be 
said to have yet come within the domain of pradical 
chemical politics. I have in mind, among other suggestions, 
the dynamical theory of van *t Hoff, published in i88t 
(" Ansichten liber die organische Cbemie "), the theory 
of eledric charges on the atoms broached by Johnstone 
Stoney in 1874, and so ably advocated by the late 
Professor v. Helmholts in his Faraday ledure in i88i, 
and the eledric polar theory of Vidor Meyer and R^ecke, 
published in 1888 ('*Einige Bemerkungen iiber den 
Kohlenstoffatom und die Valenz," Btr,^ xxi., 946, x6ao). 

Pending the rationalisation of the dodrine of valency, 
its promulgation must continue in its present form. Its 
services in the constiudion of rational formulss, espe- 
cially within the limits of isomerism, have been incalcu- 
lable. It is the ladder by which we have climbed to the 
present brilliant achievements in chemical synthesis, and 
we are not in a position to perform the ungracious task of 
kicking it away. In recalling attention to its weaknesses 
I am only putting myself in the position of the physician 
who diagnoses his patient's case with the ulterior objed 
of getting him strengthened. There can be no doubt 
that renewed vitality has been given to the dodrine by the 
conceptions of tautomerism and desmotropy, formulated 
bv Conrad Laar in 1885, ^^^ ^7 PauI Jacobson in 1887. 
The importance of these ideas is becoming more evident 
with the advancement of chemical discovery. Any attempt 
to break down the rigidly statical conception of our 
strudural formulas appears to me to be a step in the right 
diredion. Then, again, I will remind you of the prolific 
development of the dodrine in the hands of Le Bel and 
van 't Hofi' by the inuodudion of the stereochemical 
hypothesis in 1874— unquestionably the greatest advance 
in strudural chemistry since the recognition of the quadri- 
valent charader of the carbon atom. If evidence be 
required that there is a physical reality underlying the 
conception of valency, we need only point to the close 



144 



British Association. — Frof. Meldola^s Address. 



rOHlMlCALKBWt, 
I Sept. 20» 169s* 



accordance of this notion of the aBymmetric carbon atom 
with the fads of so-called ** physical isomerism " and the 
splendid results that have followed from its introdudiion 
into our science, especially in the field of the carbo- 
hjrdrates, through the investigations of Emil Fischer and 
his pupils. In other diredions the stereochemical hypo- 
thesis nas proved to be a most suggestive guide. It was 
applied by Professor v. Baeyer in 1885 (^'''•1 xviii,, 2277) 
to explain the conditions of stability or instability of cer- 
tain atomic groupings, such as the explosiveness of poly- 
acetylene compounds and the stability of penta- and 
bexa-cyclic systems. Again, in x888 this eminent chemist 
showed its fertility in a series of brilliant researches upon 
benaene derivatives (Ann., cxzxvii., 158, and subsequent 
papers). Nor can I omit to mention the great impetus 
given in this field bv the classical work of Wislicenus, 
who in 1887 applied the hypothesis to unsaturated com- 
pounds and to cyclic systems with remarkable success 
(** Ueber die riiumliche Anordnung der Atome in organ- 
ischen Molek&len,'* &c.). Quite recently Vidor Meyer 
and J. Sudborough have shown that the ability of certain 
derivatives of benzoic and naphthoic acids to form ethers 
is governed by stereochemical considerations (B/r., xxvii., 
510, 1580, 3146, and zzviii., 182, 1254). But I must avoid 
the temptation to enlarge upon this theme, because the 
whole subjed has been recently brought together by 
C. A. Bischoff in his ** Handbuch der Stereochemie " 
(Frankfurt, 2893-94), ^ work to which all who are inte- 
rested in the subjed will naturally turn for reference. 

While the present advanced state of strudural che- 
mistry may thus be looked upon as the outcome of the 
conceptions of Frankland and Kekul6, it may be well to 
bear in mind that the idea of strudure is not ntassarify 
bound up with the hypothesis of valency in its present 
form. Indeed, some advance had been made in repre- 
senting ** constitution," especially by Kolbe, before the 
formal introdudion of this hypothesis. The two ideas 
have grown up together, but the experimental evidence 
that in any molecule the atoms are grouped together in 
a particular way is really independent of any theory of 
valency. It is only after this evidence has been acquired, 
either by analysis or synthesis, that we proceed to apply 
the hypothesis in building up the strudural formula. It 
is of course legitimate to assume the truth of the hypo- 
thesis, and to endeavour by its use to convert an empirical 
into a rational formula ; but this method generally gives 
us a choice of formulae from which the true one can only 
be seleded by further experimental investigation. Even 
within the narrower limits of isomerism it is by no means 
certain that all the modifications of a compound indicated 
by hypothesis are adoally capable of existence. There 
is, for example, evidence that some of the ** position 
isomeridcs " among the derivatives of mono- and poly- 
cyclic compounds are too unstable to exist— a fad which 
in itself is sufficient to indicate the necessity for a revi- 
sion and extension of our notions of valency. Thus, by 
way of illustratioc, there is nothing in the hypothesis 
to indicate why orthoquinones of the benaene series 
should not be capable of existence ; yet it is a fad that in 
spite of all efforts such compounds have never been ob- 
tained. The conditions essential for the existence of 
these compounds appear to be that the hydrogen of the 
benzene ring should be replaced by acid substituents such 
as oxygen, hydroxyl, chlorine, or bromine. Under these 
circumstances, as Zincke has shown (firr., xx., 1776), 
tetrachlor and tetrabrom-orthobenzoquinone are stable 
compounds. So also the interesting researches of Nietzki 
have proved that in such a compound as rhodizonic acid 
{Bir,, xix., 308, and xxiii., 3136) orthoquinone oxygen 
atoms are present. But there is nothing in the dodrine 
of valency which leads us to susped that these ortho- 
quinone derivatives can exist while their parent compound 
lesists all attempts at isolation. I am aware that it is 
dangerous to argue from negative evidence, and it would 
be rash to assert that these orthoquinones will never be 
obtained. But even in the present state of knowledge it 



may be distindly affirmed that the methods which readily 
furnish an orthoquinone of naphthalene completely fail ia 
the case of benzene, and it is just on such points as this 
that the inadequacy of the hypothesis becomes apparent. 
In other words, the dodrine fails in the fundamental re- 
quirement of a scientific theory; in its present form it 
gives us no power of prevision — it hints at possibilities of 
atomic groupings, but it does not tell us d priori which of 
these groupings are likely to be stable and which un- 
stable. I am not without hope that the next great 
advance in the required diredion may yet come from the 
stereochemical extension of the hypothesis, although the 
attempts which have hitherto been made to supply its de- 
ficiencies cannot but be regarded as more or less 
tentative. 

The New Theory of Abstract Types. 
I will venture, in the next place, to dired attention to a 
modern development of strudural chemistry which will 
help to illustrate still further some of the points raised. 
For many years we have been in the habit of abstrading 
from our strudural formulas certain ideal complexes of 
atoms which we consider to represent the nucleus or type 
from which the compound of known constitution is derived. 
In other words the hypothesis of valency which was de- 
veloped originally from Gerhardt*s types is now leading 
us back to another theory of types based upon a more 
intimate knowledge of atomic grouping within the mole- 
cule. In some cases these types have been shown to be 
capable of existence ; in others they are still ideal. Used 
in this way the dodrine of valency is most suggestive, but 
at the same time its lack of prevision is constantly forcing 
itself upon the attention of chemical investigators. The 
parent compound has sometimes been known before its 
derivatives, as in the case of ammonia, which was known 
long before the organic amines and amides. In other 
instances the derivatives were obtained before the type 
was isolated, as in the case of the hydrazines, which were 
charaderised by Emil Fischer in 1875, and the hydrazo- 
compounds, which have been known since 1863, while 
hydrazine itself was first obtained by Curtius in 1887. 
Phenylazimide was discovered by Griess in 1864, and 
many representatives of this group have been since pre- 
pared ; but the parent compound, hydrazoic acid, was 
only isolated by Curtius in x89a Derivatives of triazole 
and tetrazole were obtained by Bladin in 1885 ; the types 
were isolated by this chemist and by Andreocci in 1892. 
Pyrazole derivatives were prepared by Knorr in 1883 ; 
pyrazole itself was not isolated till 1889, by Buchoer. 
Alkyl nitraroides were discovered by Franchimont and 
Klobbie many years before the typical compound, nitra- 
mide, NOa.NHa, which was isolated last year by Thiele 
and Lachman {Btr,, zxvii., 1909). Examples might be 
multiplied to a formidable extent^ but enough have been 
given to illustrate the principle of the eredion of types, 
which were at first imaginary, but which have since 
become real. The utility of the hypothesis is undeniaUe 
in these cases, and we are justified in pushing it to its 
extreme limits. But no chemist, even if endowed with pro- 
phetic instind, could have certainly foretold six jrears ago 
that the type of Griess's ** triazobenzene would be capable 
of free existence, and still less that when obtained it would 
prove to be a strong acid. The fad, established by Car- 

tins, that the group ^N- fundions in chemical m<de- 

cules like the atom of chlorine is certainly among the most 
striking of recent discoveries. Only last year the list of 
nitrogen compounds was enriched by the addition of 
CO(Ns)a, the nitrogen analogue of phosgene (Cunius* 
Bit., xxvii., 2684). 

These illustrations, drawn from the compounds of 
nitrogen, will serve to bring out the wonderful develop- 
ment which our knowledge of the chemistry of this element 
has undergone within the last few years. I mi^t be 
tempted here into a digression on the general besnog of 



CflBHtCAL NtWSt ) 

Sept. ao, 1895. f 



British Association. — Prof. Meldola's Address. 



H5 



HCv 



the Tery striking fad that an element comparatively in- 
adUve in the free state should be so remarkably adive in 
combination, but I must keep to the main topic, as by 
means of these compounds it is possible to illustrate still 
further both the strength and the weakness of our modern 
conceptions of chemical strudure. Consider some of the 
undiscovered compounds which are foreshadowed by the 
process of ideal abstradion of types. Theazoxy-compounds 
contain the complex 

\/ or •• . 

O O 

The types would be^ 

HN-NH HN-NH 

\/ or 

O O 

The first of these formulas represents the unknown dihydro- 
nitrous oxide. The azo-compounds are derivatives of the 
hypothetical diimide HN : NH. An attempt to prepare 
this compound from azodicarbonic acid (Thiele, Ann,, 
cclxxi., 130) resulted in the formation of hydrazine. The 
diethyl- derivative may have been obtained by Harries 
(Ber,, xxvii., 2276), but this is doubtful. It is at present 
inexplicable why compounds in which the group * N : N * 
18 in combination with aromatic radicles should be so 
remarkably stable, while the parent compound appears to 
be incapable of existence. The addition of two atoms of 
hydrogen converts this type again into a stable compound. 
There is nothing in the strudural formulas to indicate 
these fads. The amidines are stable compounds, and the 
so called ** anhydro-bases," or imidazoles, are remarkably 
stable ; the parent compound — 
.^NH 

has not been obtained, while its amido-derivative — 

is the well-known substance, guanidine. The isodiazo- 
compounds recently discovered by Schraube and Schmidt 
and by Bamberger (Ber,, xxvii., 514, 679, &c.) are possibly 
derivatives of the hypothetical substance O: N.N Ha, 
which might be named nitrosamide. Why this compound 
should not exist as well as nitramide is another question 
raised by the principle of abstrad types. The carbizines 
were formerly regarded as derivatives of the compounds— 
yNH .NH 

COC. and CSC. 

^NH ^NHa 

(Fischer, Ann,, ccxii., 326; Freund and Goldsmith, Ber,, 
xxu, 2456). Although this strudure has now been dis- 
proved the possible existence of the types has been sug- 
gested. Carbisine and thiocarbizine differ from urea and 
thiocarbaroide only by two atoms of hydrogen. These 
types have not been isolated; if they are incapable of 
existence the current views of molecular strudure give no 
auggestion of a reason. The diazoamides are derivatives 
of the hypothetical HaN.NH.NHa or HN : N.NHa, com- 
pounds which Curtius speaks of as the propane and 
propylene of the nitrogen series. The latter complex was 
at one time thought to exist in diazohippuramide {Ber,, 
xxtV; 3342 ; this has since been shown to be hippurazide, 
». #., a derivative of NjH {Ber,, xxvii., 779), and a biacidyl 
derivative of the former type has also been obtained {Ber., 
3344). Both these types await isolation if they are capable 
of existence. I may add that several attempts to convert 
diaaoamides into di hydro-derivatives by mild alkaline 
redndion have led me to doubt whether this nitrogen 
chain can exist in combination with hydrocarbon radicles. 
The bisdiasoamides of H. v. Pechmann and Frobenius 
(Ber,, xxvii., 898) are derivatives of the 5-atom chain 
HaN.NH.NH.NH.NHa or HN : N.NH.N : NH, a type 
which hardly seems likely to be of sufiScient stability to 
exist. The tctrazones of Emil Fischer have for their type 



the 4.atom chain HaN.N : N.NHa or HaN.NH.NH.NHa, 
of which the free existence is equally problematical, al- 
though a derivative containing the chain — N:N.NH.NH — 
has been obtained by Curtius {Ber,, xxvl., 1263). Hydra- 
zoic acid may be regarded as a derivative of triimide— 

yNH 

HN^I , 

\nh 

but this type appears to be also incapable of isolation 
(Curtius, Ber,, xxvi., 407). The hydrazidines or formazyls 
of Pinner {Ber,, xvii., 182) and of H. v. Pechmann {Ber,, 
XXV., 3175) have for their parent compound the hypothetical 
substance HaN.N : CH.N : NH. In z888 Limpricht de- 
scribed certain azo-compounds {Ber,, xxi., 3422) which, if 
possessing the strudure assigned by that author, must be 
regarded as derivatives of diamidotetrimide — 

HN-NH HaN.N-N 

II I II 

HN-NH HaN.N-N 

Both these types are at present imaginary ; whether it is 
possible for cyclic nitrogen systems to exist we have no 
means of knowing— all that can be said is that they have 
never yet been obtained. It is possible, as I pointed out 
in 1890 at the Leeds meeting of the British Association^ 
that mixed diazoamides may be derivatives of such a 
4-atom ring. 

Any chemist who has followed the later developments 
of the chemistry of nitrogen could supply numerous other 
instances of undiscovered types. A chapter on the un- 
known compounds of this element would furnish quite an 
exciting addition to many of those books which are tamed 
out at the present time in such profusion to meet the 
requirements of this or that examining body. I have 
seleded my examples from these compounds simply 
because I can claim some of them as personal acquaint- 
ances. It would be easy to make use of carbon com- 
pounds for the same purpose, but it is unnecessary to 
multiply details. It has frequently happened in the history 
of science that a well-considered statement of the short- 
comings of a theory has led to its much-desired extension. 
This is my hope in venturing to point out one of the chief 
deficiencies in the strudural chemistry of the present time. 
I am afraid that I have handled the case badly, but I am 
bound to confess that I am influenced by the same fetlinn 
as those which prevent us from judging an old and wefi- 
tried friend too severely. 

The theory of types to which we have reverted as the 
outcome of the study of molecular stmdnre is capable of 
almost indefinite extension if, as there is good reason for 
doing, we replace atoms or groups by their valency ana- 
logues in the way of other atoms or groups of atoms. The 
fads that in cyclic systems N can replace CH (benzene 
and pyridine), that O, S, and NH are analogues in fnrfn- 
rane, thiophene, and pyrrole, are among[the most familiar 
examples. The remarkable iodo- and iodoso-compounds 
recently discovered by Vidor Meyer and bis colleagnes 
are the first known instances in which the trivalent atom 
of iodine has been shown to be the valency analogue of 
nitrogen in organic combination. Pushing this principle 
to the extreme we get further suggestions for new group- 
ings, but, as before, no certainty of prevision. Thus, if 
nitrogen formed the oxide NaOa the series might be 
written— 

Nv >Nv N : O yN-O 

..>0 0<f.>0 or . O^. . 



N : o 



or 



N : o 



&c. 



Of course these formulas are more or less conjedural, 
being based on valency only. But since nitrous oxide is 
the analogue of hydrazoic acid, they hint at the possibility 
of such compounds as— 



146 



BriHsh Association. — Prof. Meldola's Address. 



i CasiiiCAL Nbws, 
1 Sept. 20, 1895. 






Hn/.NnH, &c. 



If a student produced a set of formuls corresponding to 
the above, in which NH had been substituted for O, and 
asked whether they did not indicate the existence of a 
whole series of unknown hydrogen compounds of nitrogen, 
we should probably tell him that his notions of chemical 
stroaure had run wild. At the same time I am bound to 
admit that it would be very difficult, if not impossible, to 
furnish him with satisfadory reasons for believing that 
such groupings are improbable. Compare again the 
series — 



o : c<N«^ (,) 
o:c<.. 

„c/NH, 



(3) 



yNH 
C<l 






(a) 



(4) 



H.O 



N 






(5) 



(7) 



.NH 






(6) 



(8) 



The first is urea; the second, third, fourth, fifth 
(methylene diamine), and sixth are unknown ; the seventh 
is the remarkably interesting diazomethane discovered 
last year by H. v. Pechmann {Ber,, xxvii., x888). The 
last compound, dinitromethanc, is known in the form of 
its salts, but appears to be incapable of existence in the 
free state. There is nothing expressed or implied in the 
existing theory of chemical struaure to explain why 
dinitromethane is unstable while trinitromethane is stable, 
and mono- and tetranitromethane so stable as to admit 
of being distilled without decomposition. Chemists will 
form their own views as to the possibility or impossibility 
of such a series as this being completed. Whether there 
would be a concordance of opinion I will not venture to 
iay : but any chemist who expressed either belief or dis- 
belief with regard to any special member would, I 
imagine, have great difficulty in giving a scientific reason 
for the faith which is in him. At the most he would have 
only the very unsafe guide of analogy to fall back upon. 
Perhaps by the time the British Association holds its 
next meeting at Ipswich it will have became possible to 
prove that one particular configuration of certain atoms 
IS possible and another configuration impossible. Then 
will have been achieved that peat advance for which we 
are waiting — the reunion of the two streams into which 
our science began to diverge shortly after the last Ipswich 
meeting. 

The present position of struaural chemistry may be 
summed up in the statement that we have gained an 
enormous insight into the anatomy of molecules, while 
our knowledge of their physiology is as yet in a rudimen- 
tary condition. In the course of the foregoing remarks 
I have endeavoured to indicate the direaion in which our 
theoretical conceptions are most urgently pressing for 
extension. It is, perhaps, as yet premature to pronounce 
an opinion as to whether the next development is to be 
looked for from the stereochemical side; but it is not 
going too far to exprei s once again the hope that the 
geometrical representation of valency will give us a deeper 
insight into the conditions which determine the stability of 
atomic configurations. The speculations of A. v. Baeyer, 
Wislicenus. Viaor Meyer, Wunderlich, BischoflF, and 
others have certainly turned the attention of chemists to- 
wards a quarter from which a new light may eventually 
dawn. 

The Proorbss of Synthetical Chemistry. 

If, in my earnest desire to see the foundations of struc* 
tural chemistry made more secure, I may have unwittingly 
given rise to the impression that I am depreciating its 



services as a scientific weapon, let me at once hasten 
to make amends by direaing attention to the greatest 
of its triumphs, the synthesis of natural produas, 
i.#., of compounds which are known to be produced by 
the vital processes of animals and plants. 

Having been unable to find any recent list of the 
natural compounds which have been synthesised, I have 
compiled a set of tables which will, I hope, see the 
light at no very distant period. According to this census 
we have now realised about xSo such syntheses. The 
produas of Baaeria have been included in the list be- 
cause these compounds are the results of vital aaivity 
in the same sense that alcohol is a produa of the vital 
aaivity of the yeast plant. On the other hand, the various 
uro-compounds resulting from the transformation in the 
animal economy of definite chemical substances admin- 
istered for experimental purposes have been excluded, be* 
cause I am confining my attention to natural produas. 
Of course, the importance of tracing the aaion of the 
living organism on compounds of known constitution from 
the physiological point of view cannot be over-estimated. 
Such experiments will, without doubt, in time shed much 
light on the working of the vital laboratory. 

The history of chemical synthesis has been so thoroughly 
dealt with uom time to time that I should not have 
ventured to obtrude any further notice of this subjea 
upon your patience were it not for a certain point which 
appeared to me of sufficient interest to merit re-considera- 
tion. It is generally stated that the formation of urea 
from ammonium cyanate by Wdhler in 1828 was the first 
synthesis of an organic compound. There can be no 
doubt that this discovery, which attraaed much attention 
at the time, gave a serious blow to the current concep- 
tions of organic chemistry, because urea was so obviously 
a produa of the living; animal. It will be found, however, 
that about the same time Henry Hennell, of Apothecaries' 
Hall, had really effeaed the synthesis of alcohol— that is 
to say, had synthesised this compound in the same tense 
that Wohler had synthesised urea. The history is toon 
told. In 1826 Hennell (through Brande) communicated 
a paper to the Ro^al Society which appears in the Philo* 
sophtcal Transactwns for that year ('* On the Mutual Ac- 
tion of Sulphuric Acid and Alcohol, with Observations on 
the Composition and Properties of the Resulting Com- 
pound,'* Phil, Trans.f 1826, p. 240). In studying the 
compounds produced by the aaion of sulphuric acid on 
alcohol, and known as ** oil of wine,'* he obtained sulpho- 
vinic acid, which had long been known, and gave fairly 
good analyses of this acid and of some of its salts, while 
expressing in the same paper very clear notions as to its 
chemical nature. Having satisfied himself that sulpho- 
vinic acid is a produa of the aaion in question, he then 
proceeded to examine some sulphuric acid which had ab- 
sorbed eighty times its volume of olefiant gas, and which 
hsd been placed at his disposal for this purpose by 
Michael Faraday. From this he also isolated sulpho- 
vinic acid. In another paper, communicated to the Royal 
Society in 1828 ('* On the Mutual Aaion of Sulphuric 
Acid and Alcohol, and on the Nature of the Process by 
which Ether is formed," Phil, Trans, ^ 7828, p. 365), he 
proves quantitatively that when sulphovinic acid is dis- 
tilled with sulphuric acid and water the whole of the 
alcohol and sulphuric acid which united to-form the sulpho- 
vinic acid are recovered. In the same psper he shows 
that he had very clear views as to the process of etherifi- 
cation. Hennell's work appears to have been somewhat 
dimmed by the brilliancy of his contemporaries who were 
labouring in the same field ; but it is not too much to 
claim for him, after the lapse of nearly seventy years, the 
position of one of the pioneers of chemical synthesis. Of 
course, in his time the synthesis was not complete, be- 
cause he did not start from inorganic materials. The 
olefiant gas used by Faraday had been obtained from 
coal-gas or oil-gas. Moreover, in 1826-1828 alcohol was 
not generally regarded as a produa of vital aaivity, and 
this is, no doubt, the reason why the discovery failed to 



ill«afiCAL2<iwt,t 
Sept. 90, iSds- * 



British Association. — Prof. Meldola^s Address. 



147 



woduce the tame excitement a$ the formation of urea. 
Bat the synthesis of alcohol from ethylene had, neverthe- 
less, heen accomplished, and this hydrocarbon occupied 
at that time precisely the same position as ammonium 
cyanate. The latter salt had not then been synthesised 
from inorganic materials, and the formation of urea, as 
Schorlemmer points out ('* The Rise and Development of 
Organic Chemistry,'* p. 195), was also not a complete 
synthesis. The reputation of Wohler, the illustrious 
fnend aad colleague of the more illustrious Liebig, will 
lose not a fradion of its brilliancy by the raising of this 
historical question. Science recognises no distindion of 
nationalitv, and the future historian of synthetical che- 
mistry will not begrudge the small niche in the temple of 
Fame to which Hennell is entitled. 

Like many other great discoveries in science, the arti* 
6cial formation of natural produds began, as in the case 
of alcohol and urea, with observations arising from ex- 
periments not primarily direded to this end. It was not 
till the theory of chemical strudure had risen to the rank 
of a scientific guide that the more complicated syntheses 
were rendered possible by more exad methods. We justly 
credit strudural chemistry with these triumphant achieve- 
ments. In arriving at such results any defeds in the 
tbeorv of stmdure are put out of consideration, because 
—and this point must never be lost sight of — all doubt as 
to the possibility of this or that atomic grouping being 
stable is set aside at the outset by the actual occurrence 
of the compouhd in nature. The investigator starts with 
the best of all assurances. From the time of Wdhler and 
Hennel the course of discovery in this field has gone 
steadily on. The announcement of a new synthesis has 
ceased to produce that excitement which it did in the 
early days when the so-called ** organic " compounds 
were regarded as produds of special vital force. The in* 
terest among the uninitiated now rises in proportion to 
the technical value of the compound. The present list of 
180 odd synthetical produds comprises, among the latest 
discoveries, gentisin, the colouring-matter of the gentian 
root {Qtntitma luUa), which has been prepared by 
Kostanecki and Tambor, and caffeine, synthesised by 
Basil Fischer and Lorens Ach, starting from dimethylurea 
and malonic acid. 

1 have allowed myself no time for those prophetic 
flights of the imagination which writers on this subjed 
generally indulge in. When we know more about the 
stmdure of highly comolex molecules, such as starch and 
albumen, we shall probably be able to synthesise these 
compounds. It seems to me more important just at pre- 
sent to come to an understanding as to what is meant by 
an organic synthesis. There appears to be an impression 
asDong many chemists that a synthesis is onlyeffeded 
when a compound is built up from simpler molecules. If 
the simpler molecules can ht formed diredly from their ' 
elements, then the synthesis is considered to be complete. 
Thus area is a complete synthetical produd, because we 
can make hydrogen cyanide from its elements : from this 
we can prepare a cyanate, and finally urea. In didioo- 
aries and text-books we find synthetical processes gener- 
ally separated from modes of formation, and the latter in 
their turn kept distind from methods of preparation. The 
dtstindion between formation and preparation is obviously 
a good one, because the latter has a prsdical significance 
lor the investigator. But the experience gained in draw- 
ing op the tables of synthesised compounds, to which I 
have refeired, has resulted in the conclusion that the 
terma " synthesis " and *' mode of formation *' have been 
eitfaMer onnecessarily confused or kept distind without suf* 
Scicat reason, and that it is impossible now to draw a 
liard*and-fast line between them. Some recent writers, 
aocb, for example, as Dr. Karl Elbs, in his admirable work 
on this subjed (** Die Synthetischen Darstellungs- 
methoden der Kohlenstoffverbindungen,*' Leipsi^, x8^), 
have espandcd the meaning of the word synthesis so as 
to comprise generally the building up of organic mole- 
cules by ths combination of carbon with carbon, without 



reference to the circumstance whether the coropoood 
occurs as a natural produd or not But although this 
definition is sufficiently wide to cover the whole field of 
the produdion of carbon compounds from less complex 
molecules, it is in some respeda too restrided, becanse it 
excludes such well known cases as the formstion of hy« 
drogen cyanide from its elements, or of urea from ammo- 
nium cyanste. I should not consider the discussion of a 
mere question of terminology of sufficient importance to 
occupy the attention of this Sedion were it not for a 
matter of principle, and that a principle of the very greatest 
importance, which I believe to be associated with a clear 
conception of chemical synthesis. The great interest of 
all work in this field arises from our being able, by labors* 
tory processes, to obtain compounds which are slso msoa* 
fadured in Nature's laboratory— the living organism. It 
is in this diredion that our science encroaches upon bio* 
logy through physiology. Now, if we confine the notion 
of synthesis to the building up of molecules from simpler 
molecules or from atoms, we exclude one of Nature's 
methods of producing many of these very compoondi 
which we claim to have synthesised. There can be no 
manner of doubt that a large proportion, if not a maiorityt 
of the natural produds which have been prepared arti* 
ficially are not synthesised by the animal or plant in the 
sense of building up at all. They are the resnlu of the 
breaking down->of the degradation->of complex molecules 
into simpler ones. I urge, therefore, that if in the labora- 
tory we can arrive at one of these produds by decom- 
posing s more complex molecule by means of iuitsble 
reagents, we have a perfed right to call this a ssmthesit* 
provided always that the more complex molecule, which 
gives us our compound, can be in its turn sjmthesised, 
by no matter how many steps, from iu constituent atoms. 
Thus, oxalic acid has been diredly synthesised from car- 
bon dioxide by Kolbe and Drechsel by passing this gat 
over potassium or sodium amalgam heated to 3&®. 
Whether the plant makes oxalic acid diredly out of car* 
bon dioxide we cannot at present state ; if it doss it cer* 
tainly does not employ Kolbe and Drechsel*8 process. On 
the other hand, this acid may, lor all that is known, exist 
in the plant as a produd of degradation. Many more 
complex acids, such as citric and tartaric, break down 
into oxalic acid when fused with potash. Both citric sad 
tartaric acids can now be completely synthesised ; there* 
fore the formation of oxalic acid from these by potash 
fusion is a true sjrnthesis. 

The illustration given will make clear the point which 
I am urging. The distindion between a synthesis 
and a mode of formation vanishes when ws can 
obtain a compound by the breaking down of a more com* 
plex molecule in all those cases where the latter can be 
completely built up. If we do not expand the meaning of 
synthesis so as to comprise such cases ws are simply 
shutting the door in Nature's face. It must be borne in 
mind that the adual yield of the compound fiornished by 
the laboratory process does not come into considsretion, 
because it may be generally asserted that in most cases 
the artificial processes are not the same as those which go 
on in the animal or plant. The information of real value 
to the physiologist which these syntheses give is the sug- 
gestion that such or such a compound may possibly re- 
sult from the degradation of this or that antecedent com* 
pound, and not from s process of building up from simpler 
molecules. 

The Bbaiumo op Chbmical Symtbesis on VrraL 
Cbxmistry. 

With these views^the outcome of atmdoral chemistry 
— the chemist and physiologist may join hands and move 
fearlessly onwards towards the great mystery of vital 
chemistry. In considering the results of organic synthe- 
sis two questions always arise, as it were sponuneonsly : 
How does Nature produce these complicated molecules 
without the use of strong reagents and at ordinary tern* 
peratores ? What bearing have omr laboratofy achieve* 



148 



London Water Supply. 



f CrimicalNiwi, 
I Sept 20, i69S* 



mentB on the roechaDism of vitality ? The light shed 
upon these queittoDB b^ experimental investigation has 
as yet flickered only m fitful gleams. We are but 
dwellers in the onter gates, waiting for the guide who is 
to show us the bearing of modern research on the great 
problem which confronts alike the physicist, the chemist, 
and the biologist. The chemical processes that go on in 
Che living organism are complex to an extent that is diffi- 
cult to realise. Of the various compounds of animal or 
vegetable origin that have been produced synthetically, 
some are of tne nature of waste produAs, resulting from 
metabolic degradation ; others are the result of zyinolytic 
sdion within the organism ; and others, again, are se- 
condary produds arising from the adion of associated 
Batfteria, the relationship between the Baderia and their 
host being as yet imperfedly understood. The answer 
to the Question how Nature produces complicated organic 
molecules will be much facilitated when the physiologist, 
by experiment and observation, shall have made possible 
a sound classification of these synthetical produds based 
on their mode of origination in the organism, 

The enlargement of the definition of organic synthesis 
which I have advocated has been rendered necessary by 
the consideration of certain questions which have arisen 
in connedion with the present condition of chemical dis- 
covery in this field. What evidence is there that any one 
of the z8o compounds which have been prepared artifi- 
cially is produced in the organism by a dired process of 
building up ? Is not the opposite view quite as probable ? 
May they not, from the simplest to the most complex, be 
produds of the degradation of still more complex mole- 
cules? I venture to suggest — not without some teme- 
rity, lest our colleagues of Sedions I and K should treat 
me as an intruder— that this view should be given a fair 
trial. I am aware that the opposite view, especially as 
regards plant assimilation, has long been held, and espe- 
cially since 1870, when v. Baeyer advanced his celebrated 
theory of the formic aldehyd origin of carbohydrates. It 
is but natural to consider that the formation of a complex 
molecule is the result of a building-up process. It must 
be remembered, however, that in the living organism 
there is always present a compound or mixture, or what- 
ever we like to call it, of a highly complex proteid nature, 
which, although at present indefinite from the purely 
chemical point of view, is the essence of the vitality. 
Of course I refer to what biologists have called proto- 

f>lasm. Moreover, it is perhaps necessary to state what 
s really nothing more than a truism, viz., that protoplasm 
is present in and forms a part of the organism from the 
very beginning of its existence— from the germ to the 
adult, and onwards to the end of life. Any special che- 
mical properties pertaining to protoplasm are inseparable 
from the animal or plant until that period arrives which 
Kekul^ has hinted at when we shall be able to '* build up 
the formative elements of living organisms " in the labor- 
atory {Naturit xviii., 212). But here I am afraid I am 
allowing the imagination to take a flight which I told you 
a few minutes ago that time would not admit of. 

The view that requires pushing forward into a more 
prominent position than it has hitherto occupied is that 
all the chemical transformations in the organism — at any 
rate all the primary changes — are made possible only by 
the antecedent combination of the substances concerned 
with living protoplasmic materials. The carbon dioxide, 
water, &c., which the plant absorbs, must have formed a 
compound or compounds with the protoplasmic material 
of the chloroplasts before starch, or sugar, or cellulose 
can be prepared. There is, on this view, no such pro- 
cess as ikt dinct combination of dead molecules to build 
up a complex substance. Everything must pass through 
the vital mill. The protoplasmic molecule is vastly more 
complex than any of the compounds which we have 
hitherto succeeded in synthesising. It might take up and 
form new and unstable compounds with carbon dioxide or 
formic aldehyd, or sugar, or anything else, and our pre- 
sent methods of investigation would fail to reveal the pro- 



cess. If this previous combination and, so to speak, 
vitalisation of dead matter adually occurs, the appear- 
ance of starch as the first visible produd of assimilation, 
as taught by Sachs, or the formation of a z2-carbonatom 
sugar as the first carbohydrate, as shown by the recent 
researches of Horace Brown and G. H. Morris, is no 
longer matter for wonderment. The chemical equations 
given in physiological works are too purely chemical ; the 
physiologists have, I am afraid, credited the chemists 
with too much knowledge — it would appear as though 
their intimate familiarity with vital processes had led 
them to undervalue the importance of their prime agent. 
In giving expression to these thoughts I cannot but feel 
that I am treating you to the strange spedacle of a 
chemist pleading from the physiologists for a little more 
vitality in the chemical fundions of living organisms. 
The future development of vital chemistry rests, however, 
with the chemist and physiologist conjointly ; the isola- 
tion, identification, and analysis of the prodods of vital 
adivity, which has hitherto been the task of the chemist, 
is only the preliminary work of physiological chemistry 
leading up to chemical physiology. 
(To be continued). 



LONDON WATER SUPPLY. 
Report on the Composition and Quality of Daily 
Samples of the Water Supplied to London 
FOR THE Month Ending August 31ST, 1895. 

By WILLIAM CROOKES, F.R.S., 

and 

PROFESSOR DEWAR, F.R.S. 

To Major-general A. De Courcy Scott, R.E., 
Watif Examiner t Metropolis Water Actt 1871. 

London, September loth, 1895. 
Sir, — We submit herewith, at the request of the 
Diredors, the results of our analyses of the 182 samples 
of water coUeded by us during the past month, at the 
several places and on the several days indicated, from the 
mains of the London Water Companies taking their 
supply from the Thames and Lea. 

In Table L we have recorded the analyses in detail 
of samples, one taken daily, from Aug. xst to Aug. 31st 
inclusive. The purity of the water, in reaped to organic 
matter, has been determined by the Oxygen and Com- 
bustion processes ; and the results of our analyses by 
these methods are stated in Columns XIV. to XVIII. 

We have recorded in Table II. the tint of the several 
samples of water, as determined by the colour-meter 
described in a previous report. 

In Table III. we have recorded the oxygen required to 
oxidise the organic matter in all the samples submitted 
to analysis. 

Of the 182 samples examined two were recorded as 
*' clear, but dull ;" the remainder being clear, bright, and 
well filtered. 

The rainfall in the Thames Valley during August has 
been close upon the average. The adual amount is 2*28 
inches, and the twenty-five years* mean is 2*24, showing 
an excess of 0*04 inch. By far the greater part of the 
rain fell in the first part of the month, only 0*36 inch 
having fallen since the 14th. 

The Thames- derived waters still maintain the high 
degree of purity we had to record in the reports for June 
and July. Compared with the waters in July, there is 
scarcely any analytical difference. Compared with the 
waters for the corresponding month last year, there is an 
appreciable diminution in some of the constituents, as 
seen by the following table. 

Our baderiological examinations of the unfiltered 
Thames waters and of the clear water drau n from the 
general wells of the Water Companies show that the mi- 
crobial life in the river is diminishing, whilst the Com- 



CaBMicAL News, I 
Sept. ao. 1895* f 



British Association jor the Advanument 0/ Science. 



149 



Companson of th4 Avnofis of ihi Fivt Thamis-dirivid 
SuppUisfor thi Months o/Augustt 1894 ^^ 1^95* 
CoanDOO Nitric Oiygen. Organic Organic 

Salt. Add. Hardness, reqd. Carbon. Carbon. Colour. 
Per Per Per Per Per 

gall. gall. Degrees, gall. gall. gall. Br'n:Blne. 
Means. Means. Means, Means. Means. Maxima. Means. 

1894 2*077 0*589 22*30 0*048 0*105 0*138 21*5*. 20 

1895 1*994 0740 13*09 0*039 0*093 0x08 1x7:20 



pantet* filters continoe to work with efficiency. The 
unfiltered waters contained an arerage of 1720, and the 
dear filtered waters flowing into the pipes contained an 
average of 34 baderia per c.c. These were all harmless 
river microbes. 

We are, Sir, 

Your obedient Servants, 

William Crookbs. 
Jambs Dewar. 



CORRESPONDENCE. 

DISINFECTANTS. 

To ih€ Editor of the Chemical News. 
Sir, — In yoor reviewer*s notice of my book on ** Disinfed- 
ants '* he adds to the following quotation from p. xi the 
words which I have italicised :—*' A large number of 
processes have endeavoured to recover the phosphate 
of uwiig€ by using the sludge as a fertiliser, but they have 
all met with little commercial success ;'* and then pro- 
ceeds to say, this statement *<we must pronounce as 
utterly mistaken.'* His own additional words are those 
which have led him to express this opinion, as the context 
shows the phosphate referred to is not the phosphate of 
sewage, but the phosphate of animal charcoal, the whole 
of this sedion being devoted to remarks on the use of 
this material for purifying and deodorant purposes. — I 
am, &c., 

Samuel Ridbal. 
Chemical Laboratory, 
28, ViaorU St., WettniaBter. S.W., 
September a, 1895. 



MISCELLANEOUS. 

British Association for the Advancement of 
Science.— The following are the names of the Officers 
and Committee of Sedion B (Chemical Science) at the 
Ipswich Meeting of the British Association :— 

President^Frof. R. Mcldola, F.R.S., Foreign Sec C.S. 

Vice-Prisidents—Frof. P. P. Bedson. D.Sc. ; Prof. H. 
B. Dixon, M.A., F.R.S.; Prof. E. Frankland, D.C.L., 
F.K.S.; Dr. J. H. Gladstone, Ph.D., F.R.S. ; Prof. Ira 
Remsen. Ph.D.; Sir H. E. Roscoe. D.C.L.. F.R.S. 

SecretarUs—E. Herbert Fison, C. A. Kohn. Arthur 
Harden (Recorder), J. W. Rodger. 

Commtttii^Ftof. H. E. Armstrong, F.R.S.; R. N. 
Atkinson ; J. Carter Bell ; C. H. Bothamley ; Prof. J. 
Campbell Brown; Prof. F. Clowes; T. Fairley; A. E. 
Fletcher; C. J. Fowler; Prof. Franchimont; A. G. 
Vernon Harcourt, F.R.S., Pres. C.S.; Prof. Liveing, 
F.R.S. ; Prof. H. McLeod, F.R.S. ; H. Forstcr Morley ; 
Manning Prentice ; Lord Rayleigh, Sec. R.S. ; A. 
Richardson; Prof. A. Smithells ; J. Spiller; Prof. R. 
Warington, F.R.S. ; W. Marshall Watts; Prof. W. 
Carleton Williams; G. Young. 

The Papers brought before the Sedion were as fol* 
lows : — 

President's Address. 

Sir H, B. Roscoe and Arthur Harden— A New View of 
the Genesis of Dalton's Atomic Theory, derived from 
Original Manuscripts. 



Dr, y. H, Gladstone — Report of the Committee on the 
Teaching of Science in Elementary Schools. 

G. y. Fowler— Tht Adion of Nitric Oxide on some 
Metallic Salts. 

Prof. F. Clowes— The Respirability of Air in which a 
Candle Flame has Burnt until it is Extinpiished. 

D. 7. P. Berridge—The Adion of Light upon the 
Soluble Metallic Iodides in presence of Cellulose. 

Dr. C, A, Kohn— RtpoTtof the Committee on Quantita- 
tive Analysis by means of Eledrolysis. 

Sir H, E. Roscoe — Report of the Committee Appointed 
to Prepare a New Series of Wave-length Tables of the 
Spedra of the Elements. 

A Discussion was held in conjundion with Sedion K 
(Botany^ on the Relation of Agriculture to Science. The 
Discussion was introduced by the following papers : — 

Prof. R. Warington— How Shall Agriculture best ob* 

tain Help from Science ? 
r. Hendrick — Agriculture and Science. 
Af. y. R, Dunstan—Tht Application of Science to 

Agriculture. 

r. B. Wood— V/ovk at the Experimental Plots in 
Norfolk and Suffolk. 

Report of the Committee on the Preparation of Pore 
Haloids. 

Report of the Committee on the Bibliography of 
Spedroscopy. 

Dr. H. W. Vogel—Somt Remarks on Orthochromatic 
Photography. 

C. H. Bothamley — The Sensitising Adion of Dyes on 
Gelatino-bromide Plates. 

Report of the Committee on the Adion of Light on 
Dyed Colours. 

Dr. y. y. Sudborough—Somt Stilbene Derivatives. 

Dr. y. y. Sudborough—H oit on the Constitution of 
Camphoric Acid. 

Dr. M, iyi7<frrm<iNn— Experimental Proof of Van't 
Hoff*s Constant, of Dalton*s Law, &c., for very Dilute 
Solutions. 

H. y. H. Finton—Tht Formation and Properties of a 
New Organic Acid. 

Dr. M. Wildermann — On the Velocity of Readion be- 
fore perfed Equilibrium takes place. 

C. F. Cross and C. Smith— Tht Chemical History of the 
Barley Plant. 

Joint Sitting of Sedions A and B x— 

Lord Rayleigh, See. R.S.—Oa the Refradion and Vis- 
cosity of Argon and Helium. 

Dr, y. H, Gladstone, F.R,S.— On Specific Refradion 
and the Periodic Law, with reference to Argon and other 
Elements. 

A Discussion *< On the Evidence to be gathered as to the 
Simple or Compound Charader of a Gas, from the Con- 
stitution of its Spedrum.'* The Discussion was opened 
by Prof. A. Schuster, F.R.S. Lord Rayleigh, Sec. R.S., 
and Prof. Runge and others joined in the Discussion, and 
Dr. Johnstone Stoney, F.R.S., read a paper on ** The 
Interpretation of Spedra.*' 

The Chemical Laboratory of Wie8baden.^In the 
Summer Term, 1895, there were fifty-four students on the 
books. Of these, thirty-four were from Germany, four 
from England, four from Norway, two from Aostro- 
Hungary, two from Holland, two from Belgium, two from 
Australia ; also one from each of the following countries — 
Switzerland, Italy, Russia, and United States of America. 
In place of Professor Bor^mann, deceased in April, Dr. 
L. Griinhut has been nominated as teacher of chemical 
technology. Other changes in the teachers have not taken 
place. Tne assistants in the instrudion laboratory were 
three in number, in the Versuchsstationen (private labora- 
tories) twenty. The next Winter Term begins the 15th 
of Odober. The Versuchsstation has been appointed as 
one of the institutions where chemists can receive the 
pradical instrudion in the analysis of food necessary for 



150 



The People's Palace. 



I CVBMtCAL MSWt, 

1, Sept. 90^ 189s. 



the admission to the examinatioo for food analysts. 
Daring the last term, besides the scientific researches, a 
great number of analyses were undertaken in the different 
departments of the Laboratory and the Versuchsstation 
on behaU of manufadure, trade, mining, agriculture, and 
hygiene. 

The People's Palace.— In the South Kensington Ex- 
aminations last year, the Day School obtained 2 Honours 
First, 4 Honours Second ; 56 Adv. First, 131 Adv. Second; 
455 Elementary Passes. Evening Classes, 4 Hon. First, 
7 Hon. Second ; 23 Adv. First, 139 Adv. Second ; 200 
elementary Passes in science subjeds. In addition to 
these, zx First, 68 Second, and 47 Elementary Passes 
were obtained by the Day School in Mathematics, and 
3 First 26 Second, and 7 Passes by the Evening Class 
students. Among the latter are included 10 students who 
were successful in the Department Examination in Conic 
Sedions and Differential and Integral Calculus. In Art, 
the Day School obtained 121 First and 138 Second, and 
the Evening Classes 2 Excellent, 104 First, and 135 
Second. In the Evening Classes successes were like- 
wise obtained in the City and Guilds Examination and 
in those of the University of London. Out of 50 London 
County Council Evening Exhibitions awarded to students 
from various polytechnics, 21 were obtained by those from 
the People's Palace. The chemical laboratory has been 
entirely re-fitted through the generosity of the Drapers' 
Company. 

Charterhouse Science and Art Schools and Literary 
Institute. — The Winter Session will commence on 
Saturday, September 28th, under the Presidency of the 
Rev. Henry Swann, M.A. During the late Session up. 
wards of 1200 students, mostly elementary teachers, 
availed themselves of the privileges offered by this Insti- 
tution. Of this number, 682 presented themselves for 
examination, and were successful in obtaining a large 
number of certificates awarded by the Science and Art 
Department of South Kensington. Several students 
prepared for the Lond. B.Sc. (Int.) Examination. In- 
strudion of a pradical charader is given in most of the 
sciences at a very nominal fee, whilst in Art at an equally 
low rate students, under the diredion of competent in- 
strudors, can be advanced in their studies. Those 
who have leisure can, at a very moderate charge, 
attend the Day Classes in Art. Day Classes will be held 
to prepare candidates for Matriculation (Lond.), the 
Clericid, Medical (including Dental), and other Examina- 
tions. Students who aim at becoming proficient in 
Chemistry (Organic and Inorganic) have the opportunity 
of working in a well-fitted laboratory. Aspirants for 
university honours can, at a very small expense, be 
assisted in their studies. Classes for Matriculation, 
Microscopy, Latin, Greek, French, German, Shorthand, 
and Music are taught by well-qualified teachers. Oppor- 
tunities for the study of photography, &c., are to be 
continued this Session. Full particulars of the classes 
are to be obtained from C. Smith, Organising Secretary. 
An organised Day Science School for Boys and Girls is 
now in full operation. A special course of ledures on 
Agriculture, Hygiene, and Physiology is arranged for the 
coming Session. 

Battersea Polytechniclnstitute.— This Institute has 
been built and equipped at a cost of over ;f 55,000, the 
greater part of which has been raised by voluntary sub- 
scripttons. It is at present in possession of a fixed endow- 
ment of £2500 per year from the City Parochial Founda- 
tion. The London County Council also contributes an 
annual sum, estimated to amount to about ;£'25oo. It is 
under the diredion of a Governing Body consisting of 
representatives of the South London Polytechnics Com- 
mittee, the City Parochial Foundation, the London 
County Council, and the London School Board. The 
principal work of the Institute is the provision of Evening 
Classes for both sexes in all subjeds of Technology, Pure 
and Applied Science, Art, Commerce, Domestic Economy, 



and Music ; but it also provides a Technical and Science 
Day School for Boys and Girls, a Training School of 
Domestic Economy, and a Domestic Economy School for 
Girls. During the last Session, 1894 95, the Evening 
Classes were attended by over 2930 persons, while x6o 
students were in regular attendance at the Day Schools. 
The Institute is provided with well equipped workshops, 
and also with laboratories for Engineering and Mechanics, 
Eledrical Engineering, Physics, Chemistry, and Natural 
Science. Classes will commence on September 23rd. 



CHEMICAL LABORATORY, 

WIESBADEN, GERMANY. 

Director— Prof. R. FRESENIUS, Ph.D. 

tProf.R.PRBSBNIUS, Ph.D. 
Prof.H.FRESBNIUS, PhJ>. 
W. FRESENIUS, Pb.D. 
E. HINT2, Pb.D. 

LECTURES. 
Experimental Chemistry (Inorganic) Prof. H. FRESENIUS, Pb.D. 

s&m""' ?.''''•'." :: :: :: ::}w.FRESENius.Ph.D. 

Organic GhemUtry E. HINTZ, Ph.D. 

Chemical Technology L. GRUNHUT, Ph.D. 

Microtcopy, with exercises in Micro- 1 xi/ » wm^ nu t> 

scopicwork | W. LENZ, Ph.D. 

( Prof.H. FRBSSNIUS.Ph.D 
Chemistry and Analysis of Foods .. \ W. FRESENIUS, Ph.D..mnd. 

Le. HINTZ, Ph.D. 

PraftlJal ei'ercises'in Bkctiriology ! '. } ^'- "®**- °* PRANK. 
Technical Drawing, with exercises . . J. BRAHM. 

The next Session commences on the xsth of OAober. The Rafnla- 
tions of the Laboratory and the Syllabus of Leaures will be forwarded 
gratis on application to C. W. Krbidbl's Verlag, at Wiesbaden, or to 
the undersigned. 

Prof. R. FRESENIUS, Ph.D. 

THE 6LAS60W AND WEST OF SCOTLAND 

TECHNICAL COLLEGE. 
qphe DIPLOMA of the COLLEGE is granted 

**- in the following departments of Engineering and other 
branches of APPLIBD and GENERAL SCIENCE. 

Cnemical Engineering. 

w 

Engl 



Civil Engineering 
Mechanical Engineering. 
Naval Architedture. 
Eledtrical Engineering. 
Architedture. 



Metallurg 

Mining Engineering. 

Agriculture. 

Chemistry. 



Mathematics and Physics. 

Special Courses of Study extending over Three Aeademical Yeara 
have been arrsnged in each of the above departments. Average fee 
per Session £14 14s. 

Students may enrol in any of the Separate Courses of LeAures, or 
in any of tht Laboratories, provided they are qualified to take advan- 
tage oi the instrudtion given. 

The LABORATORIES for Pra«ical InstruAion in PHYSICS. 
CHEMISTRY, TECHNICAL CHEMISTRY, METALLURGY, 
and ELECTRICAL ENGINEERING, and the ENGINEERING 
WORKSHOP are liberally equipped with the most approved 
apparatus. 

Session X895-96 commencet on TUESDAY OCTOBER xst. 

ENTRANCE EXAMINATION begina on Tuesday, Septem- 
ber 24tb. 

For CALENDAR (price xs. 4|d. by post), containing detailed syl- 
labuses of each course, particulars of fees, scholarships, &c., apply to 

JOHN YOUNG, B.Sc. 
38, Bath Street, Glasgow. Becreury. 



NOTICE TO ANALYSTS AND LABORATORY 
DIRECTORS. 

Rest METHYLATED SPIRIT, manufac- 

J-' turcd by A. & J. WARREN, Wholesale Druggists, Dealers 
in Chemicals for Analytical Work, and Methylated Spirit Makers. 
23 and 24, Redcliff Street, Bristol. For Four-pence a Pamphlet on' 
Methylated Spirit, written by Algernon Warren, is obuinable from 
the Publisher, J. W. Arrowsuitk, Quay Street, Bristol: and 
SiMFXiN, Marshall, Hamiliom, Kimt, and Co., Ltd.^ London. 



' ut!^^. tl^'' \ British A ssociation.—Prof. Meldola's Address. 



THE CHEMICAL NEWS 



Vol. LXXIL, No, 1870. 



ADDRESS TO THE CHEMICAL SECTION 

OP THE 

BRITISH ASSOCIATION. 
Ipswich, 1895. 

By Prd. RAPHAEL MBLDOLA. F.R.S., P.I.C.Pob. Sbc. C.S.. 
Pretidant of the Seftion. 

(CoDcloded horn p. 148). 

Pbotgplasiuc Theory op Vital Synthesis. 
The soppotition that chemical synthesis 10 the or- 
Kanism is the result of the combination of highly 
complex molecales with simpler molecules, and that 
the anstable compounds thus formed then undergo 
decomposition with the formation of new produas, 
may be provisionally called the protoplasmic theory 
of TiUl synthesis. From this standpoint many of the 
preinuling doarines will have to be inverted, and the 
formation of the more complex molecules will be consi- 
dered to precede the synthesis of the less complex. It 
may be urged that this view simply throws back the pro- 
cess of vital synthesis one stage, and leaves the question 
ol the origin of the most complex molecules still unex- 
plained. I grant this at once; but in doing so I am 
simply acknowledeing that we have not yet solved the 
enigma of life. We are in precisely the same position as 
is the biologist with resped to abiogenesis, or the so-called 
'* spontaneous generation." To avoid possible miscon- 
ception let me here state that the protoplasmic theory in 
BO way necessitates the assumption of a special " vital 
force.*^ All that is claimed is a peculiar, and at present 
to us mysterioos, power of forming high-grade chemical 
combinations with appropriate molecules. It is not alto* 
gether absurd to suppose that this power is a special 
property of nitrogen in certain forms of combination. 
The theory is but an extension of the views of Kuhoe, 
Hoppe -Seyler, and others, respeding the mode of adion 
of enxymes. Neither is the view of the degradatiooal 
origin cf synthetical produds in any way new.* I merely 
have thought it desirable to push it to its extreme limit 
in order that chemists may realise that there is a special 
chemistry of protoplasmic adion, while the physiologists 
may exercise more caution in representing vital chemical 
transformations by equations which are in many cases 
purely hypothetical, or are based on laboratory experi- 
ments which do not run parallel with the natural process. 
The chemical transformations which go on in the living 
organism are thus referred back to a peculiarity of proto- 
plismic matter, the explanation of which is bound up 
with the inner mechanism of the process of assimilation. 
If, as the protoplasmic theory implies, there most be 
combtnation of living protoplasm with appropriate com- 
pounds before synthesis is possible, then the problem 
resolves itself into a determination of the conditions 
which render such combination possible,— i. #., the con- 
ditions of assimilation. It may be that here also light 
will come from the stereochemical hypothesis. The first 
step was taken when Pasteur found that organised fer- 
ments had the power of discriminating between physical 
isomerides; a similar seledive power has been shown to 
reside in enxymes by the researches of Emil Fischer and 

• See, i. g.t Vlnet's " Leanres on the Phyiiolosy of Plants.** pp. 
145. atS, aa7 tw, and 234. Prmaically all the great clasies of syf- 
tbatkal prodoaa art regai ded at the resulti of the deitruAive meU- 
boUtm oi proloplaana. A iptcial plea (or protoplaimic aaion hat 
•lao btto urctd, from tbt biolofical tide, by W. T. Tbiteltoa-Dvcf. 
7o«ni. Ckm. 5#r., 1693 ; Trant., pp. 680, Mi. ' ' 



151 

his coadjutors. Fischer has quite recently expressed the 
view that the synthesis of sugars in the plant is preceded 
by the formation of a compound of carbon dioxide, or of 
formic aldehyd, with the protoplasmic material of the 
chloroplast, and similar views have been enunciated by 
btohmann. The question has further been raised by 
van'tHoflF, as well as by Fischer, whether a stere<^ 
chemical relationship between the living and dead com- 
pounds entering into combination is not an absolutely 
essential condition of all assimilation. The settlement 
of this question cannot but lead us onwards one stage 
towards the solution of the mystery that still surrounds 
the chemisty of the living organism. 

Recent Discoveries of Gaseous Elements. 
The past year has been such an eventful one in the way 
of startling discoveries that I must ask indulgence for 
trespassing a little further upon the time of the Seaioo. 
It was only last year, at the Oxford meeting of the BriUsh 
Association, that Lord Rayleigh and Prof. Ramsay so. 
nounced the discovery of a gaseous constituent of the 
atmosphere which had up to that time escaped deteaion. 
The complete jiistification of that announcement is now 
before the world in the paper recently published in the 
Phtloiophical TransacHoHi of tht Royal Soci$ty. The his- 
tory of this bri liant piece of work is too recent to require 
much recapitulation. I need only remind you how, as 
the result of many years' patient determinations of the 
density of the gases oxygen and nitrogen, Lord Rtyleigh 
established the faa that atmospheric nitrogen was heavier 
than nitrogen from chemical sources, and was then led to 
suspea the existence of a heavier gas in the atmosphere. 
He set to work to isolate this substance, and succeeded 
in domg so by the method of Cavendish. In the mean- 
time Prof. Ramsay, quite independently, isolated the eas 
by removing the nitrogen by means of red-hot magnesium, 
arid the two investigators, then combining their labours, 
followed up the subjea, and have given us a memoir 
which will go down to posterity among the greatest 
achievemcnu of an age renowned for its scientific 
aaivity. 

The case in favour of argon being an element seems 
to be now settled by the discovery that the molecule of 
the gas IS monatomic. as well as by the distinaness of its 
elearic spark spearum. The suggestion put forward soon 
after the discovery was announced, that the gas was an 
oxide of nitrogen, must have been made in complete 
Ignorance of the methods by which it was prepared. The 
possibility of its being Nj has been considered by the 
discoverers and rejeaed on very good grounds. Moreover, 
Peratoner and Oddo have been recently making some ex- 
periments in the laboratory of the University of Palermo 
with the objea of examining the produas of the elearo. 
lysis of hydrazoic acid and its salts. They obtained only 
ordinary nitrogen, not argon, and have come to the con- 
clusion that the anhydride N3.N3 is incapable of existence, 
and that no allotropic form of nitrogen is given off. It 
haa been urged that the physical evidence in support of 
the monatomic nature of the argon molecule, vix., the 
ratio of the specific heats, is capable of another interprets* 
tion— that argon is, in laa, an element of such exW>r. 
dinary energy that its atoms cannot be separated, but are 
bound together as a rigid system which transmits the 
vibrational energy of a sound-wave as motion of trans* 
lation only. If this be the state of affairs we must loak 
to the physicists for more light. So far as chemistry is 
concerned, this conception introduces an entirely new set 
of ideas, and raises the question of the monatomic cha- 
raacr of the mercury molecule which is in the same 
category with respea to the physical evidence. It seems 
unreasonable to invoke a special power of atomic linkage 
to explain the monatomic charaaer of argon, and to 
refuse such a power in the case of other monatomic 
molecules like mercurv or cadmium. The chemical 
inertness of argon has been referred also to this same 
power of self-combination of its atoms. If thisexplana. 



152 



British Association. — Prof. Meldola^s Address. 



f Crbmical, Niws, 
I Sept. 37.1895. 



tion be adopted it carries with it the admission that those 
elements of which the atoms composing the molecule are 
the more easily dissociated should be the more chemically 
aAive. The reverse appears to be the case if we bear in 
mind Vidor Meyer's researches on the dissociation of the 
halogens, which prove that under the influence of heat 
the least adive element, iodine, is the most easily disso- 
ciated. On the whole, the attempts to make out that 
argon is polyatomic by such forced hypotheses cannot at 
present oe considered to have been successful, and the 
contention of the discoverers that its molecule is mon- 
atomic must be accepted as established. 

In searching for a natural source of combined argon 
Professor Ramsay was led to examine the gases contained 
in certain uranium and other minerals, and by steps which 
are now well known he has been able to isolate helium, a 
gas which was discovered by means of the spedroscope 
in the solar chromosphere, during the eclipse of x868, by 
Professors Norman Lockyer and E. Frankland. In his 
Address to the British Association in 1872 {Reports, 1872, 
p. Ixxiv) the late Dr. W. B. Carpenter said :— 

** But when Frankland and Lockyer, seeing in the 
spedrum of the yellow solar prominences a certain bright 
line not identifiable with that of any known terrestrial 
flame, attribute this to a hypothetical new substance 
which they propose to call helium, it is obvious that 
their assumption rests on a far less secure foundation, 
until it shall have received that verincation which, in the 
case of Mr. Crookes*s researches on thallium, was 
aflbrded by the adual discovery of the new metal, whose 
presence had been indicated to him by a line in the 
spedrum not attributable to any substance then known.*' 

It must be as gratifying to Professors Lockyer and 
Frankland as it is to the chemical world at large to know 
that helium mav now be removed from the category of 
solar myths and enrolled among the elements of terres- 
trial matter. The sources, mode of isolation, and pro- 
perties of this gas have been described in the papers 
recently published by Professor Ramsay and his col- 
leagues. Not the least interesting fad is the occurrence 
of helium and argon in meteoric iron from, Virginia, as 
announced by Professor Ramsay in July {Nature^ vol. lii., 
p. 224). Like argon, helium is monatomic and chemically 
inert, so far as the present evidence goes. The conditions 
under which this element exists in cleveite, uranioite, and 
the other minerals, have yet to be determined. 

Taking a general survey of the results thus far oh- 
laised, it seems that two representatives of a new group 
of monatomic elements charaderised by chemical inert- 
ness have been brought to light. Their inertness 
obviously interposes great difficulties in the way of their 
further study from the chemical side ; the future develop- 
ment of our knowledge of these elements may be looked 
for from the physicist and spedroscopist. Prof. Ramsay 
has not yet succeeded in effeding a combination between 
argon or helium and any of the other chemical elements. 
M. Moissan finds that fluorine is without adion on 
argon. M. Berthelot claims to have broueht about a 
combination of argon with carbon disulphide and mer- 
cury, and with <* the elements of benzene, . . . with the 
help of mercury," under the influence of the silent elec- 
tric discharge. Some experiments which I made last 
spring with Mr. R. J. Strutt with argon and moist 
acetylene submitted to the eledric discharge, both silent 
and disruptive, gave very little hope of a combination 
between argon and carbon being possible by this means. 
The coincidence of the helium yellow line with the D3 
line of the solar chromosphere has been challenged, but 
the recent accurate measurements of the wave-length of 
the chromospheric line by Prof. G. E. Hale, and of the 
line of terrestrial helium by Mr. Crookes, leave no doubt 
as to their identity. Both the solar and terrestrial lines 
have now been shown to be double. The isolation of 
helium has not only furnished another link proving com- 
dTunityof matter, and, by inference, of origin between the 
earth and atm, but an extension of the work by Professor 



Norman Lockyer, M. Deslandres, and Mr. Crookes has 
resulted in the most interesting discovery that a large 
number of the lines in the chromospheric spedrum, as 
well as in certain stellar spedra, which had up to the 
present time found no counterparts in the spedra of ter- 
restrial elements, can now be accounted for by the spedra 
of gases contained with helium in these rare minerals. 
The question now confronts us, Are these gases members 
of the same monatomic inert group as argon and helium ? 
Whether, and by what mechanism, a monatomic gas can 
give a complicated spedrum is a physical question of su- 
preme interest to chemists, and I hope that a discussion 
of this subjed with our colleagues of Sedion A will t>e 
held during the present meeting. That mercury is capable 
under different conditions of giving a series, of highly 
complex spedra can be seen from the memoir by J. Nl. 
Eder and E. Valenta, presented to the Imperial Academy 
of Sciences of Vienna, in July, 2894. With resped to 
the position of argon and helium in the periodic system 
of chemical elements, it is, as Professor Ramsay points 
out, premature to speculate until we are quite sure that 
these gases are homogeneous. It is possible that they 
may be mixtures of monatomic gases, and in fad the 
spedroscope has already given an indication that they 
contain some constituent in common. The question 
whether these gases are mixtures or not presses for an 
immediate answer. I will venture to suggest that an 
attack should be made by the method of diffusion. If 
argon or helium were allowed to diffuse fradionally 
through along porous plug into an exhausted vessel there 
might be some separation into gases of different densities, 
and showing modifications in their spedra, on the assump- 
tion that we are dealing with mixtures composed of 
molecules of different weights. 



THE REFRACTION AND VISCOSITY OF ARGON 

AND HELIUM.* 

By The Right Hoo. Lord RAYLBIGH, Sec.R.S. 

As compared with dry air, the refradion (11 - z) of argon 
is 0*961 and that of helium (prepared by Prof. Ramsay) is 
as low as 0*146. 

Dry air being again taken as the standard, the viscosity 
of argon is x*2i, and that of helium is 0*96. 



ON THB 

PRESENCE OF ARGON AND OF HELIUM 

IN CERTAIN MINERAL WATERS. 

By Dr. C. H. BOUCHARD. 

The escape of very fine gaseous bubbles occurring in cer- 
tain sulphuretted waters from the Pyrenees has been ob- 
served long ago. It begins a short time after such water 
has been drawn, and continues for a time variable accord- 
ing to the springs, sometimes for hours. In these waters, 
rendered slightly alkaline by sodium sulphide and silicate, 
these gases can neither be oxygen nor carbonic acid. It 
has been admitted, doubtless in consequence of the nega- 
tive charader of this substance, that it can only be 
nitrogen. 

Spanish physicians have especially fixed their attention 
on this feature. They have named the waters which 
evolve nitrogen *' azoades." They are found on the 
Spanish slope of the Pyrenees at Panticosa. On the 
French slope they are found at several stations, especially 
at the medicinal springs of BagnereS'de-Bigorre and at 
Cauterets, at the source of the Raillidre. 



* Read before the British A&io€iatioo (Sedion B), Ipswich 
Meeting, 2895. 



CntMicALNtwtfi 
Sept. 27. 1895. f 



Reactions 0/ Pormaldehyd. 



153 



Other springs in the Pyrenees which do not show any 
eflfenrescence allow at intervals the escape of large 
bubbles of gas which are also considered as nitrogen. 

During a recent stay at Cauterets, I had the curiosity 
to colled information of the gases which occasion these 
two kinds of phenomena. I succeeded in collediog some- 
what considerable quantities of these gases at the point of 
issue, before any cootad with the atmosphere, at the 
source of the Railliire and at two of the springs which 
feed the source of the Bois. 

I have, thanks to the kindness of M. du Perron, the 
diredor of the waters, been enabled to examine the gas 
tiuaded from the bottled water of the Railliire, obtained 
by means of the mercurial pump, and also by ebullition. 

Our colleague, M. Troost, who was present at my first 
experiments, has kindly offered his assistance for the 
determination of the physical and chemical charaders of 
these gases, and the results which I now communicate to 
the Academy have been obtained with his assistance and 
ander his direAion. 

These gases, when dried over potassa and phosphoric 
anhydride, have the charaders of nitrogen ; if heated to 
redness over magnesium wire for forty-eight hours, they 
lose their original volume. At the same time the wire 
is covered with a yellow layer, which on exposure to the 
air becomes white and evolves ammonia. 

If the gas thus reduced is introduced into Plucker 
tubes with magnesium wires, and if under a low pressure, 
and with an efiluve capable of heating the magnesium 
soflSctently, we exhaust the last traces of nitrogen (the 
spedrum of which disappears), we observe that the residual 
gases from the different springs are not identical. 

The gases colleded at the spring of the Railliere or 
extraded br boiling the waters of the same spring have 
given the charaaeristic rays of argon as well as those of 
helium. 

The gases coUeded at the springs of the source of the 
Bois have all given both the charaderistic rays of helium. 

The gases colleded at one of the two springs of the 
Bois (the one having the lowest temperature) lead us to 
suaped, on account of the abundance of rays in the red 
and the oranee, that they contain some other element 
along with helium. 

In our present ignorance of the physiological properties 
of argon and helium, we may ask if there is any relation 
between the medicinal properties of the waters of the 
Pjrrenees and the composition of the gases which they 
evolve. The fad seems to me improbable. 

The idea proposed twenty-five years ago by the Spanish 
physicians that the ** azoades *' owe their virtues to the 
nitrogen which they evolve has been abandoned. May 
these virtues, in default of nitrogen, depend on gases 
which are chemically less adive than nitrogen, and which 
are present in the waters in a smaller proportion ? It 
ia, stridly speaking, possible ; but the question ought not 
even to be raised iiit is demonstrated that these gases are 
found also, and in analogous proportions, in the waters 
which flow or remain on the surface of the earth, and 
which serve os for dietetic purposes. 

We are not absolutelv certain concerning the origin of 
all the gases of mineral waters, and it may be that those 
with which we are concerned have their origin in the air 
carried down into deeper regions by the superficial waters. 
These waters, itfter beine alkalised by a sulphide, may 
rc-ascend towards the surface necessarily deprived of oxy- 
gen and carbonic acid, and containing merely nitrogen 
and argon. Nevertheless, it seems at present that to the 
possible atmospheric origin of a part of the argon, and 
perhaps of the helium, there must be added some subter- 
ranean adion, since if one of our springs contains both 
gates, another contains only helium, and a third contains 
along with helium something which is not argon. 

The investigation which we have just made involves a 
research into the composition of the Keses contained in 
waters on the surface of the earth. The results of this 



study, which is in progress, will be communicated to the 
Academy.— Coi»i^</« R$ndus, cxxi., p. 39a. 



THE COMBINATION OF MAGNESIUM WITH 

ARGON AND HELIUM. 

By L. TROOST aod L. OUVRARD. 

If it is requisite to examine if there exists argon or helium 
in nitrogen gas it is not indispensable to pass the mixture 
over magnesium heated to redness or over lithium heated 
to dull redness in order to absorb the larger part of the 
nitrogen before causing the effluve to ad on the gaseous 
mixture. The use of Plucker tubes with magnesium wire 
and a Rhumkorff coil fitted with a Marcel Depres inter- 
rupter, enables us to ad at once upon a mixture contain- 
ing only very small proportions of argon and helium. 

This we have observed especially with the gases col- 
leded by Dr. Bouchard at the spring at the source of the 
Railliere, and at those of the Bois (at Cauterets). 

We may at once Introduce the dried gases in(g Pliicker 
tubes with magnesium wires, and pass into thein strong 
efHuves. The nitrogen is only slowly absorbed at first, 
but when the pressure is sufficiently decreased the tem- 
perature of the magnesium wires rises sufficiently to oc^ 
casion a commencement of evaporation which gives a 
metallic deposit in the state of a mirror 00 the ^ass of 
the tube around the wires. The combination of nitrogen 
with the magnesium vapour, which takes place with ex- 
treme rapidity, and the spedmm of nitrogen disappears. 
After this moment, the red rays charaderistic of argon 
may be distindly seen, or the red ray, D4, and the otner 
rays charaderistic of helium. 

The brightness of these spedra may be increased bf 
introducing at intervals fresh quantities of the gas into tbn 
Plucker tube, fitted with a good glass cock, and passing 
in again strong efiluves. 

If we continue the passage of strong effioves for somn 
hours, the luminous intensity of the rays diminishes by 
degrees, and a complete vacuum is formed. The Argon 
and helium which do not seem to combine in a sensibkB 
manner with magnesium heated to redness, combine with 
this metal, or rather with its vapour, under the prolonged 
influence of powerful efiluves. 

As Berthelot as pointed out, the use of the effluve con- 
stitutes the most efiedive procedure to determine these 
combinations. 

In argon, platinum presents phenomena of evaporation 
and combination analogous to those presented by magne- 
%\xim*^Comptei Rindus, cxxi., p. 394. 



SOME REACTIONS OF FORMALDEHYD. 
By T. H. LBB. 

Formalin (40 per cent formaldehyd) from Schering, of 
Berlin, was taken. 

Permanganate of potassium immediately reduced. The 
formaldehyd folly oxidised to COf and water. Ferric 
chloride solution (hot) is somewhat deepened in colour 
when formaldehyd is added. On allowing to cool, then 
re-heating and adding a little ammonium hydrate, a bulky 
red precipitate of baste ferric formate appears. 

Ammoniacal silver solution appears to be reduced in 
two stages, viz. : — 

1. Ag|0+H.COH a Aga+H.COaH. In this stage 
the silver falls in the specular form. 

a. AgaO+H.COaH « Aga+HaO+COa. In this stage 
the silver falls in a pulverulent form. 

A hot solution of potassium ferricyanide was made 
ammoniacal and a little formalin and sulphate of copper 
solution added. A brown precipitate immediately ap« 



154 



Rejraction and Dispersion of Liquid Oxygen. 



i CRBHICAL NlWt, 

1 Sept. 27. 1895. 



peared. The same reagents minus the formalin gave a line 
green solation. This I regard as evidence of the redadion 
of ferricyanide to ferrocyanide. 

Hot Fehling*8 solution is rapidly reduced by formalde- 
hyd. 

Ammoniacal copper sulphate pir se is not reduced. 
Mercuric chloride is not reduced. 

Alkaline mercuro-potassium iodide is immediately re- 
duced to metal in the cold. 

Bdgcombe VilUt Clevedon. 



ON THE REFRACTION AND DISPERSION 

OF LIQUID OXYGEN.* 

By Profetsori LIVEINQ mad DEWAR. 

In August, 1892, we published in the Philosophical Maga- 
tint (vol. xxxiv.. p. 208) a measure of the refradive index 
of liquid oxygen at its boiling-point for the yellow sodium 
rays, made by means of a prism. In the following year 
(vol. xxxvi., p. 330) we published a measure of the same 
quantity made by a different method. For the reasons 
stated, we could only obtain measures more or less ap- 
proximate to the truth. Since then we have made several 
attempts, but hitherto in vain, to make hollow prisms with 
vacuous jackets, in which the liquid oxygen could be kept 
In a tranquil state while the observations were going on. 
We have also attempted unsuccessfully other methods of 
tflikiog the measures. 

The chief difficulties which we encountered in making 
our former measures arose from the irregularities and 
striations of the glass vessels, and from the continual 
ebullition of the liquid oxygen. These difficulties have 
now b^n to a great extent obviated. We have come back 
to the method we used in 1893, which we then described as 
the method of MM. Terquem and Trannin, but which 
bad previously been suggested by Prof. E. Wiedemann 
(Archivts de GenHe, li., p. 340. 1874). However, for the 
cylindrical vessel before used we substituted a globular 
vessel having the inside of its vacuous jacket silvered all 
over except a narrow vertical strip about 4 m.m. wide, 
which was left unsilvered to allow of the passage of 
light. This vessel was used, exadly as the cylindrical 
vessel had been used in the former experiments, as a lens 
by which an image of a source of light was thrown on 
to the slit of a spedroscope. The pair of glass plates, 
separated by a thin stratum of air and fixed to a rod 
which was the prolongation of the vertical axis of a 
theodolite, were arranged at about the centre of the 
globe. The oxygen in the globe was very tranquil, and 
the silvering cut off all light which did not pass nearly 
centrally through the globe. The result was that the 
light of the rays observed was cut off, when the glass 
plates were turned through the proper angle, much more 
sharply than before, and the measures are so much more 
trustworthy. 

We found the spark between cadmium eledlrodes a 
convenient source of light, both because the rays are 
bright, and because they are dispersed through a consider- 
able range in the visible spedrum, and it was possible 
to watch their extindion one after another as the glass 
plates were- slowly turned. Even with this arrangement 
the extindion of the rays when liquid oxygen was in the 
globe was not quite so sharp as when the experiment was 
made with alcohol. This was probably due to the scat- 
tered light from the bubbles in the oxygen, and was more 
troublesome in regard to the brightest rays. 

We obtained, as the mean of several observations, for 
the blue ray of cadmium, A. 4416, /i«> 1*2249; for the red 
ray, A 6438, /x~i'22ii ; for the green ray of thallium, 
A 535, /u»i'22i9. Also, by using a flame, we obtained 

* From the Philoiophical Magazine tor September, 



for the red ray of lithium, A. 6705, /is 1*2210, and for the 
yellow rays of sodium, A. 5892, /iax'2214. 

The last figure is less than we had foand in 1892 by 
the prism method, which was 1*2236, and still less than 
than that found in 1893, which was 1*226. It is also less 
than thst recently found by Olszewski and Witrowski, 
(Bull, d$ VAcad, dt Cracovit, July, 1894, p. 246), which 
was between 1*2222 and 1*2235. The values we have 
now found for the refradive indices corresponding to the 
red ray of lithium and the green ray of thallium are also 
less than those found by Olszewski and Witrowski, which 
were about 1*22x3 and 1*2235 respeAively. We think, 
however, that our measures for the red and blue rays of 
cadmium are better than those made for the thallium and 
sodium rays. 

These give, for the mean green, /i nearly equal to 1*222, 
and, taking the density of oxygen at its boiling*point as 
Z'X37, the refradion-constant by Gladstone's formula — 

^^« •01953, 
and by Lorenz's formula— 

Jl =0*X242. 

(fi*+2)rf ^ 

Takine RegnauU's value for the density of oxygen gas 
at 0° and 76 cm., viz., 0*00143, and Mascart's value for 
the mean refradive index, viz., 1*000271, we find for 
gaseous oxygen the refradion-constant — 



and— 



''.J -0*18947. 






B0*Z263i. 



It will be seen that this last is nearly equal to the 
refradion-constant as above determined for the liquid. 

In Mascart*8 paper ** Sur la Refradion des Gaz '* 
{Annalts VEcoU Normale Experimintal, 1876) some ob- 
servations on the ** Dispersion of Oxygen and other 
Gases *' were given, which enable a comparison to be 
made between this property in the gaseous and liquid 
states. Taking Cauchy's formula— 



.-.-«(. +jj.) 







z 


I 










»•-« 


h 


Aa 


X* 








n + 1 




1 + 


6 



then— 



A* 

From this b is calculated by Mascart, and is called the 
Coefficient of Dispersion. The blue and red cadmium 
lines represent the extremest difference of wave-lengths 
employed. This gave for oxygen the maximum and 
minimum values 0*0049 and 00078, and mean value 
0*0064 for the Constant of Dispersion. Taking the values 
for the liquid state given above, the value of b becomes 
0*0064. It seems, therefore, that the Dispersion Constant 
in the liquid state is identical with that of the gas. 



The Examinational System.— At the recent Con- 
gress of the Society of Chemical Industry, held at 
Leeds, July sist to August 2nd, Dr. T. E. Thorpe, F.R.S., 
in his Presidential Address, expressed the timely opinion 
that we need institutions of research where young men, 
no longer haunted by the spedra of the ever-threatening 
examination, may find time and scope to pradise their 
minds in real investigations and try their powers in 
attempts to promote Science and extend its domain. 



Cmbmical Nmm% \ 
Sept. 27, 1893. I 



Calaverite from Cripple Creek. 



155 



CALAVERITE FROM CRIPPLE CREEK, 

COLORADO.* 

By W. F. HILLBBRANO. 

Thb occurrence of tellurium in the ores of the mining 
distrid of Cripple Creek, Colorado, has been known from 
an early day in the as yet brief industrial history of that 
region. That it was, in part at least, associated with 
gold was likewise known from the observance of a crys- 
tallised gold- tellurium mineral. Although the ores of the 
distrid are chiefly gold carriers, they contain also a little 
silver, and since recognised silver minerals had not been 
observed, or at most only in minute amount, it seemed 
probable that the silver was associated with the gold in 
the tellurium compound. Indeed, Mr. R. Pearce, of 
Denver, came to the conclusion, from his examination 
iProc, Colo, ScL Soc, Jan. 8 and April 5, 1894) of certain 
ore concentrates, that this mineral was sylvanite. It is, 
however, of very sparing occurrence, so that it was only 
by dint of much effort that material in sufficient purity for 
decisive tests was obtained by Prof. R. A. F. Penrose, 
jun., who transferred it to me for chemical examination. 
The material was derived from three different mines in 
order to ascertain whether it was of constant or varying 
composition, or, in fad, whether there might not be more 
than one specific telluride. That the composition does 
vary within narrow limits the analyses show, but there is 
no reason apparent for assuming more than one species. 

The material from the Prince Albert mine, the first 
received, was with little trouble brought into an almost 
ideal condition of purity. It was in part apparently fairly 
well crystallised, but the measurements made by Prof. 
S. L. Penfield, of New Haven, are unfortunately not deci- 
sive as to the system of crystallisation, as shown by his 
notes at the close of this paper. The specific gravity of 
this material was 8*91 at 24° C, which becomes 9'oo when 
correded for a small admixture of silico-ferruginous 

fangue of assumed specific gravity 270 (probably low), 
he other samples were imperfedly crystallised and held 
too much foreign matter of uncertain composition to make 
specific gravity determinations of any value. 

Analyses of CalavtriU, 

I. II. III. 

AuS?! R*ven C. O. D. 

^nfl »i°«- »'"«• 
mine. 

Tellurium (Tc).. .. 5727 47*69 53'89 

Gold(Au) 3895 33*93 39*3 » 

Silver (Ag) 3*2X x-47 © «5 

Insoluble 0*33 5-80 0-91 

Ferric oxide (FcaOs) . . 0*12 (n) 

Iron(Fe) 5*4i 1*67 

Sulphur (S) 6-17 (*) 1-58 (2-96 FeSa) 

Manganese (Mn) • . 0*23 (c) 

Calcium (Ca) .... 0*51 

Magnesium (Mg) .. 0*10 
Oxygen, fluorine, and 

soluble silica, by 

difiierence . # . . 0*95 (rf) 

99*88 100*47 zoo'oo 
{a) This was included with the insoluble matter in ar- 

riving at the correded density. 
(6) Calculated from the Fe to make FeSa. 
(c) AsMnOa? ^ . ^ 

(a) A part of the calcium found in solution was derived 
from fluorite, which likewise constituted some of 
the soluble matter in this instance. 
Selenium has been reported to occur in traces in the 
distrid (F. C. Knight, Proc. Colo, Set, Soc, Od. i, 1894), 
but it could not be deteded in the amount of mineral 
taken for the above analyses. 

♦ Prom the Amifican Journal of Siunce, vol. 1., August, 1895. 



Excluding everything but gold, silver, and tellurium, 
and re-calculating to zoo, the following comparison is ob« 
tained : — 

III. RaUo. 
5730 2-09 
41-801 
o-9o| 



I. 
Te .. 57*6o 
Au . . 39' 
Ag.. 3' 



i7l 
23/ 



Ratio. 
2*OI 



100*00 




1*00 



ZOO'OO 



ZOO'OO 



The ratio here obtaining is that for sylvanite and cala* 
verite, but the very low percentage of silver shows that 
the mineral is calaverite. Indeed, the first analysis 
agrees almost exadly with Genth*s analysis of the species. 
Interesting is the slight variation in the ratio between 
gold and silver, end the very low percentage of silver in tbp 
mineral from the C. O. D. and Raven mines. Calaverite, 
the lowest silver carrier of the gold-silver tellurides, has not 
heretofore been known to carry less than 3 per cent of 
silver. 

The pyrognostic charaderists of the mineral from the 
Prince Albert mine were essentially those ascribed to 
calaverite. In the closed tube it fuses, giving a white 
coating near the assay, and a globular grey coating just 
above, which latter by strong heat can be in part driven 
higher up, leaving the glass covered with the same white 
fused coating as lower down. This latter is yellow while 
hot. On charcoal the mineral fuses with a green flame, 
giving a white coating and similar fumes, and leaving a 
yellow bead. The colour is pale bronze yellow, in powder 
greenish grey. The hardness is not less than and perhaps 
a little over 3. Specific gravity, as given above, 9*00. 

The identity of the telluride occurring at Cripple Creek, 
which in oxidising gives free gold and oxidised tellurium 
compounds,* seems thus satisfadorily established, but 
unless there is another richer in silver the mode of occur- 
rence of the silver in some of the ores is still in large 
part unaccounted for. It may be derived from a very rich 
argentiferous tetrahedrite of which Prof. Penrose sub- 
mitted a small specimen for identification. This carries 
over II percent of silver, but is said to be excessively 
scarce, and therefore hardly to be considered in this con- 
nedion, unless indeed this should have been the original 
source of most of the silver and later have sufifored oxida- 
tion to a great extent, whereby the silver hsw become more 
evenly distributed throughout the ore. 

Professor Penfield has kindly contributed the following 
notes on the crystallography of the mineral :— 

** The crystals of calaverite which were examined were 
developed with prismatic habit, but the prismatic sone 
was striated to such an extent that it was impossible to 
identify a single face in the zone, and on the refleding 
goniometer almost an unbroken band of signals was ol^ 
tained in a revolution of 360°. Owine to oscillatory com- 
binations the crystals were also much distorted, so that 
they did not present regular cross sedions. 

The prisms were attached so that doubly terminated 
ones were not observed, while the faces at the free end 
were small and developed with so little symmetry that 
after a study of a number of ciystals it was found impos* 
sible to determine with certainty the system of crystal- 
lisation. 

The crystals do not exhibit the perfed cleavage ascribed 
to sylvanite and krennerite, but are similar to the former 
in some of their angles. When placed in position to 
show their relation to sylvanite they have their prismatic 
development parallel to the b axis. One crystal, which 
owing to its development was more carefully measured 
than any of the others, was apparently a twin about loi, 
and showed at the end the forms iii and no. The 
measurements compared with the corresponding ones of 
sylvanite are as follows : — 

* From tests made by rovaelf on a number of specimens coUeded 
by Prof. Penrose the combination seems to be chiefly, it not alto- 
gether, with iron, bat whether as tellurite or tellurats could not be 
ascertained. 



156 



Reduction of the Adds of Selenium by Hydriodic Acid, {^^^t^ 



Sylvanite. 
iiiA(ixi)overtwinniogpIane93^35' 94*^30' 
no A (no) „ „ 35 2 34 43 

no A in 3<5 35 37 3 

X 10 A nx in twin crystal 36 33 37 3 

Other forms which were measured could not be referred 
to the sylvanite axes, and it seems probable from their 
development and lack of symmetry that the crystals are 
triclinic ; but no satisfadion was obtained after a long 
and careful study of the limited supply of material on 
hand. 

In conclusion, therefore, it may be stated that the crys- 
tals are probably triclinic, but near sylvanite in angles 
and axial ratio.*' 



THE REDUCTION OF THE ACIDS OF 

SELENIUM BY HYDRIODIC ACID.* 

By F. A. GOOCH mad W. G. REYNOLDS. 

A MBTHOD for the iodometric determination of selenious 
acid has been recently announced by Muthmann and 
Schaefer {Birichti d, D, Chem. OtselL, xxvi., xoo8) which 
is based upon the reduAion of selenious acid by hvdriodic 
acid and the dired titration of the iodine thus liberated. 
To determine the selenious acid it is only necessary to 
add it in solution to an acidulated solution of potassium 
iodide, when iodine and selenium are both set free in ele- 
mentary form, the former being diredly determinable by 
titration with sodium thiosulphate after addition of starch. 
The difficulty in the process is said to be the nncertaintv 
as to the exad point in the titration at which the starch 
blue disappears from the liquid in which the finely divided 
and opalescent selenium is held in suspension. For this 
reason the process is recommended for use only when 
great accuracy is not essential. 

Evidently if the readion between the acidulated iodide 
and lelenious acid is single and complete, the process 
should be capable of improvement by removing the 
selenium before the titration is attempted. This we have 
succeeded in doing without difficulty. We find the most 
convenient and rapid way to remove the finely-divided 
selenium is to filter the liquid containing it by means of 
the vacuum pump upon a thick felt of asbestos in a per- 
forated crucible or cone of large filtering surface. With 
a properly prepared filter of this description there is no 
difficulty in separating the selenium in a very few 
moments so completely that it is possible to determine 
the iodide remaining dissolved in the excess of potassium 
iodide with all the accuracy charaderistic of this most 
exad of titration processes. We find, however, that 
when the difficulty of determining the end*rea6ion in the 
titration of the iodine by the thiosulphate is overcome, it 
becomes apparent that the readion upon which Muthmann 
and Schaefer depend is not perfect Either the redudion of 
the selenious acid to selenium is not complete, or else the 
iodine remains in combination to a slight extent with the 
selenium and so fails to appear in the filtrate. This is 
evident from the results of the experiments of Table I., in 
which the selenious acid and potassium iodide acidulated 
with hydrochloric acid were brought together, the liquid 
thrown upon the asbestos filter, the selenium washed 
until free from soluble iodine, and the filtrate containing 
the iodine treated as usual with sodium thiosulphate in 
presence of starch. The details of treatment are described 
sufficiently in the table. The selenium dioxide was pre- 
pared for the work from the so-called pure elementary 
selenium by dissolving it in strong nitric acid, evaporating 
off the excess of the last, treating the solution of the residue 
n water with barium hydroxide, filtering to remove sclenic 

• Contributions from the Kent Chemical Laboratory of Yale Col- 
lege. From the American JouvntU of Suence, vol. 1., Sept., 1895. 



acid formed in the oxidation and traces of sulphuric add 
possibly present as an impurity, recovering the selenium 
dioxide b^ evaporation, and purifying; it by subliming and 
re-subliming it in a current of dry air until it was clean 
and white. 

Table I. 



SeO, 

taken. 



Volume 
KI HCl used before 
• (Sp. sr. I ao). filtering. 



Grm. Qrme. Cm.* C.m.t 



SeO. 
found* 
Grm. 



Brror. 
Grm. 



0'0499 X 5 xoo 0*0479 o'oo20— 

0*0499 X 5 100 0*0477 0*0022 — 

0*2035 3 5 100 0*1896 0*0x39— 

From these fibres it is plain that iodine was not found 
in the filtrate m amount corresponding to the selenium 
dioxide present. In the following experiments of Table 
II. an excess of the thiosulphate was added before filter- 
ing off the selenium so that there should be every oppor- 
tunity for the iodine and thiosulphate to interad before 
the removal of the selenium. In two experiments the 
proportion of hydrochloric acid was increased ten-fold for 
the purpose of seeing whether the presence of a large 
amount of free acid influences the result. 

Table II. 
Volume 



SeO, 


KI 


HCl uaed. before 


SeO. 
found. 




taken. 


used. 


(Sp.gr. i*ao). filtering. 
Cm.* C.m.t 


Brror. 


Gnn. 


Grmi. 


Grm. 


Grm. 


0*0499 




5 100 


0*0489 


0*00x0 


0*0499 




3 XOO 


0*0485 


0*00x4 


0*0499 




50 100 


0*0489 


0*00x0 


0*0499 




50 100 


0*0488 


O'OOXX 


0'2006 




5 xoo 


0*1925 


0*0081 


0*2030 




5 100 


01945 


0*0085 



These results show improvement over those obtained 
when filtration is made before adingwith the thiosul- 
phate, but it is obvious that the presence of a large pro- 
portion of free hydrochloric acid is without efifeft upon the 
readion, and that the iodine set free and measured is atill 
deficient in proportion to the amount of selenium dioxide 
present. Plainly the reduAion of the selenium dioxide ia 
incomplete, or else there is formed between the seleniam 
and iodine a combination, such as was noticed by Haute- 
feuille (Comptei Rindus, Ixviii., 1554) in the interaaion of 
iodine tipon hydrogen selenide. In either case it should 
be possible to push the readion farther toward completion 
by submitting the mixture of selenious acid, potassiam 
iodide, and hydrochloric acid to distillation. We have 
used for this purpose an apparatus emplojred atod 
described in connexion with previous similar work in 
this laboratory. The distillation flask is a Voit gas- 
washing flask, and this is sealed to the inlet tube of a 
Drexel wash-bottle used as a receiver, to the outlet tube 
of which is sealed a Will and Varrentrapp absorption ap- 
paratus to serve as a trap. The mixture to be distilled 
was introduced into the flask, a solution of 3 grms. of 
potassium iodide in 100 cm.* of water was put into the 
receiver and trap and during the distillation a slow cur- 
rent of carbon dioxide was passed through the apparatoa 
to keep the boiling regular. Naturally the acidified solu- 
tion of the iodide in the flask retains with great tenacity 
traces of dissolved iodine, so that, in order to determine 
all the iodine liberated in the rea^ion, the residue in the 
flask as well as the distillate in the receiver and trap was 
titrated in the usual way with sodium thiosulphate. The 
details of treatment and the results are recorded in 
Table III. 

These results are all fairly good, though all a little de- 
ficient, for amounts of seleninm dioxide up to 0*2 gnn. ; 
but when the amount of the dioxide reaches 0*5 grm. ihe 
iodine found in the distillate and in solution in the reandue 
falls far below the theory based upon the assumfl^Eooihat 
the produas are selenium, iodine, and water, '^^t sele- 
nium in the residue was left after the boiling in f^ot dense 



Cbbmi 

Sept, 


CAt MBWt, 1 

27. 1893. 1 


Report of Co 


mmittee 




Table III. 










HClin 


Total 








ScO, 


Klio 


flatlc 


volaroe 


Time 


ScO, 
foond. 




taken. 


flatk.(8p.er.r20). boileJ. 


in 


Error. 


Grn. 


Grou. 


0.m.» 


am.* 


minatei. 


Qnn. 


Grm. 


0-0499 


X 




60 


5 


0*0497 


0*0002- 


0-0499 


X 




60 


5 


0-0497 


0*0002 - 


OXM99 


X 




60 


xo 


0*0496 


0*0003- 


0*3000 


3 




60 


10 


0-X995 


0*0005- 


O*30OO 


3 




60 


xo 


0-I99X 


0*0009- 


o*ao23 


3 




60 


10 


0*20x8 


0-0005- 


0*50x8 


3 




60 


xo 


0*4635 


0*0383 - 



cryttalline condition in the experiments with the smiller 
amounts, so that it did not interfere with the titration of 
the free iodine ; bnt in the last experiment, in which ap- 
proximately 0*5 grm. of the dioxide was treated, the 
■eleniam remained in pasty form adhering to the flask. 
Subsequent examination proved that the pasty selenium 
held iodine, which was liberated slowly to water, and 
more rapidly to an aqueous solution of potassium iodide. 
The largest errors have been found (excepting that of the 
last experiment from the discussion) when the free iodine 
was filtered off from the reduced selenium ; better results 
were obtained when the precipitated selenium was first 
treated with the thiosulphate before filtering; and in the 
distillation process the best approximations are made to 
true indications. It is obvious that as the proportion of 
selenium and iodine increase, the tendency to form a 
combination is more manifest. The error thus introduced 
in the determination of the selenium dioxide by the dis* 
filiation procest is allowable up to the limit of 0*2 grm. 

Potassium iodide in hydrochloric acid ads much less 
readily upon selenic acid than upon selenious acid. 
When the hydrochloric acid is present in small propor- 
liooa in the mixture of selenic acid and the iodide the 
rcdoAion is very imperfeA, but it tends to approach 
completion as the strength of hydrochloric acid is in* 
creased. 

It is obvious, in the li^ht of the previous experiments 
with selenious acid, that it is unreasonable to exped the 
full liberation of iodine in the aAion of selenic acid upon 
the iodine when the free iodine is not removed from the 
sphere ol aAion as it is liberated. In the distillation 
process the case is otherwise, and there is no reason to 
anticipate that the determination of selenic acid should 
present greater difficulty than is encountered in treating 
selenious acid under similar circumstances. The experi- 
ments of Table IV., in which selenic acid (obtained by 
oxidising known amounts of selenium dioxide by means 
d potassium permanganate in the manner described in a 
previous paper from this laboratory— Gooch and Clemens, 
Awuf, yonm, ofScitna, 1. 51) is treated according to the 
distillation method outlined above for the determination 
of selenious acid, show that this expedation is realised, 
and that the analytical results are fairly good. 



Table IV. 



S«0. 
takes. 
Grm. 

0*0593 
00593 
0-0593 
0-X779 
01779 
0*1779 



HClin 



Total 

KI in fla»k. volume 

(Sp. gr. i'2o). iKriled. 

C.m.» 



Gmt. 
I 
I 
3 
3 
3 
3 



C.m.s 
60 
60 
60 
60 
60 
60 



Time 
io 

minutes. 

5 
5 

10 
xo 
xo 

ID 



SeO. 

found. 
Grm. 

0*0593 
0*0591 
0*0596 
o*X769 
0*1780 
o*X764 



Error. 
Grm. 

0*0000 
0'0002 — 
0*0003 + 
0*0010- 
0*0001 + 
0*00x5 - 



In conclusion, it is plain that while the simple contad 
of solutions of selenious acid or selenic acid and potassium 
iodide acidified with hydrochloric acid does not determine 
the liberation of the full amount of iodine which would 
be expedked if selenium, iodine, and water were the sole 
produds of adion, it is possible to bring about such adion 
with a close approximation to completeness, when the I 
aatotmts of selenium present are not too large, by sub- / 



m Atomic Wetghts. 157 

mitting such mixtures to distillation. We prefer, la 
applying the readion to analytical purposes, to work with 
the apparatus and under the conditions described,— 
treating, preferably, not more than 0*3 grm. of the sele- 
nium oxide, usiuK from x grm. to 3 grms. of potassium 
iodide in the distilling-flask with 5 cm.* of strong hydro- 
chloric acid in a total volume of 60 cm.*, sod continaing 
to boil for ten minutes. 



R£PORT OF COMMITTEE ON ATOMIC 

WEIGHTS, PUBLISHED DURING 189+* 

By P. W. CLARKB. 

(CoDtioaed from p. xo6). 

Cobalt and Nickbi*. 
The atomic weights of these two metals have been re- 
determined by Winkler (Z«f7. Anorg. Chtm, viil., z), who 
adopts a radically new method, using the pure eledrolytfc 
elements as a starting-point. In each case the weighed 
metal, deposited upon platinum, is treated with a weighed 
excess of iodine dissolved in potassium iodide. The metals 
are thus converted into iodides, and the excess of iodine 
is then measured by titration with thiosulphate solution. 
Thus the dired ratios, Co : I, Ni : I, are determined. Two 
series of estimations are given for each metal, with results 
as follows. The atomic weights used in calculation are 
H-x, 1^x26*53. 

First Str'm^CohaU, 



Wt. Co. 


Wt.I. 


AtwtCo. 


0-4999 
05084 
0-5290 
0*6822 
0*67x5 


3*xa8837 
2*x66750 
a-a54335 
2-908399 
2*86x6x7 


59;4a4a 

59-3M8 

59-35«a 
59-3824 




Mean •• 


593849 




Second Smis-^obalt, 




0*5185 
05267 
0*53x9 


2*209694 
2*246037 
2*268736 


59-3798 
593430 
59-3294 



Mean of all, Cob 59*3678 



Mean 



593507 





First SiriiS^Nickil. 




Wt.Ni. 


Wt.1. 


At.wt.Ni. 


0-5144 
04983 

0*6876 


2*217494 
2*148502 
3*268743 

3*970709 
2*965918 


58*6703 
58-69x8 

58*6838 
58*6678 




Mean .. 


58*6878 




Second Scrics^Nickel, 




0*5120 
0*5200 
0*5246 


2*205627 
2*204x07 
2*259925 


587436 
587732 
587432 



Mean of all, Niss58*7i55. 
For OsBi6 these become — 



Mean 



587433 



Co* 

Ni- 



'59-517 
58*863. 



(To be coQtinned>. 



* From the Journal of tht American Chtmicai Socittjf, vol. svii^ 
No. 3* Resd At th« Bottoa If tstiog, Dec. a8, 1B94. 



158 



Determination oj Antimony as Antimonic Antimoniate. 



{Cbbmical News, 
Sept. 27* «8»5- 



WARNING AGAINST THE USE OF 

FLUORIFEROUS HYDROGEN PEROXIDE IN 

ESTIMATING TITANIUM. 

By W. F. HILLEBRAND. 

DuNNiNGTON {youm. Am. Chitn, Soc, xiii., 210) has 
pointed out a source of error to be guarded against in 
estimating titanium in rocks and minerals by Weller*s 
method, due, as he believes, to the partial reversion, in 
certain cases, of ordinary titanic to meta-titanic acid, 
which does not afford a yellow colour with hydrogen per- 
oxide. It remains for me to indicate another source of 
error in the possible presence of fluorine in the hydrogen 
peroxide. 

For two years the colorimetric method has given reason- 
able satisfadion in this laboratory, but recently a new lot 
of hydrogen peroxide was purchased, of a different brand 
from that hitherto used, and, after a time, it was noticed 
that the results obtained were in some instances far too 
high, and that no two determinations agreed. 

It is known that hydrogen peroxide does not produce a 
yellow colour in titanium solutions carrying hydrofluoric 
acid or fluorides, and, moreover, the addition of even a 
drop of the dilute srcid to an already peroxidised titanium 
solution weakens the colour. For this reason it is necessary 
to take the greatest care to ensure the complete expulsion 
of all fluorine when dissolving rocks or minerals by means 
of hydrofluoric and sulphuric acids prior to the colorimetric 
estimation. A drop of hydrofluosilicic acid ads simi> 
larly, but the latter reagent cannot be made to completely 
discharge the colour even if added in great excess. 

This, however, was not suspeded as the cause of our 
trouble until, on referring to the circular of one of the 
leading makers of hydrogen perexide in America, whose 
produd has always given satisfaAory results in titanium 
work, it was found that among the various acids enume- 
rated as usually to be found in the commercial article, 
hydrofluoric acid appears. Talbot and Moody, in the 
Technology Quarterly, v., 123, mention hydrofluosilicic acid 
as of frequent occurrence in the peroxide manufadured a 
few years ago. On examining the suspeAed peroxide by 
neutralising with fixed alkali, evaporating to dryness, and 
heating wiOi strong sulphuric acid, fluorine was deteded 
bv the odour of the acid evolved and by its adion on 
gUss. 

It is therefore imperative to use only hydrogen peroxide 
which is free from fluorine in estimating titanium, for its 
presence may utterly vitiate the results, even if only 2 or 
3 c.c. of the peroxide are employed. — ydumal of the 
American Chemical Society, xvii.. No. 9. 



DETERMINATION 
ANTIMONIC 



OF ANTIMONY 
ANTIMONIATE. 



AS 



iBy OTTO BAUNEK. 



The method of determining antimony as antimonic anti- 
moniate devised by Bunsen has for some time fallen into 
discredit, after having been formerly in almost universal 
use and being recommended in the last edition of the 
text-book of Fresenius as decidedly trustworthy. The 
cause is chiefly a subsequent publication of Bunsen*8, in 
which he completely abandons as untrustworthy the 
method which he had previously recommended, and su- 
persedes it by a new procedure — the determination of 
antimony as pentasulphide. According to his investiga- 
tions the temperature of the decomposition of the 
tetroxide is not much higher than that of its formation, 
so that it is difficult to seize the point when the weight of 
the contents of the crucible corresponds to the tetroxide 
of the antimony taken. On continued ignition the weight 
of the crucible progressively diminishes, and even 



0*1 £rm. of the substance can be completely volatilised in 
six hours. 

This observation is diredly contradidory to the state- 
ments of most text-books and manuals of chemistry, even 
the most recent, which charaderise the tetroxide as 
infusible and fixed on ignition. This contradidion, as 
well as the circumstance that the above method is still in 
extensive pradice and has been recommended in various 
recent manuals of quantitative analysis, induced me to 
examine thoroughly the permanence of antimony tetroxide 
on ignition, and the consequent trustworthiness of the 
above method of determination. 

Chemically pure antimony, obtained by reducing the 
purest potassium antimoniate with potassium cyanide.* 
was weighed off and oxidised with nitric acid, whilst the 
crucible was covered with a watch-glass. After the latter 
had been rinsed out the contents were evaporated to dry- 
ness, and the residue heated in an uncovered crucible — at 
first gently, and then at redness, until the weight is con- 
stant. The weight of the contents of the crucible exadly 
corresponded to the weight of the antimony employed as 
calculated from the formula Sba04. The crucible was 
then left uncovered for several hours at a bright red-heat 
without the slightest loss of weight. 

In this manner an entire series of determinations was 
effeded with different quantities of antimony. Hence it 
appears that, on proceeding as above, the antimonic anti- 
moniate can be used as a form of weighing antimony. 

I then sought to ascertain under what conditions anti- 
mony tetroxide may be volatilised on ignition. 

A weighed quantity of antimony was oxidised in the 
manner above described, and ignited until the weight was 
constant. The lid of the crucible was then put on, and 
the ignition continued under otherwise similar conditions. 
On taking off the cover, after five minutes, its inside was 
found covered with shining needles of teroxide, whilst a 
white fume ascended from the crucible, the weight of 
which had naturally considerably decreased. The sintered 
residue was then pulverised, weighed off in a porcelain 
crucible of equal size, and ignited apain with the same 
flame but without cover. After ignition for an hour not 
the slightest decrease of weight was perceptible. If the 
ignition was then repeated in the covered crucible the 
former phenomenon reappeared, and there was again a 
sublimate of teroxide on the inside of the lid. 

As the tetroxide is persistent on ignition, even on the 
exclusion of air,— as it appears from its behaviour on 
ignition in a closed tube, when there appears not the 
slightest trace of a sublimate,— its decomposition into 
teroxide and oxygen on ignition in a covered crucible 
can be referred only to the redudive a^ion of the flame 
gases — an assumption which is verified by the following 
experiment :— 

A porcelain crucible, such as was used in the previous 
experiment, was suspended in a circular disk of asbestos- 
pasteboard in such a manner as to include tightly the 
edge of the crucible. The antimonic acid was then 
converted into tetroxide by ignition in an open crucible 
until the weight was constant. The cover was then put 
on, and the crucible heated for one hour to bright redness 
without any loss of weight or the appearance of a trace 
of sublimed teroxide. If the disk was then removed the 
same flame, in a very short interval, occasioned a strong 
redudion to teroxide. 

In this manner the volatilisation of antimony tetroxide 
— with decomposition into teroxide and oxygen — as ob- 
tained by Bunsen is easily explained. The flame-gases 
are caught under the projeding edge of the cover of the 
crucible, displace the air in the interior of the crucible, 
and exert a redudive adion. This is also the case if the 
flame does not enwrap the entire crucible, but merely 

* This reduAion can be effedted without fear of an explosion if a 
•mall quantity of the mixed substancee is fused in a capacious por- 
celain cmcible, and the rest is added to the glowiof mdt in small 
portions, waiting each time until the violeot rcaAion it at an end. 



Sept. «7 »ig«. I roisons. 

its lower part. Bat if the interior of the crucible can 
freely communicate with the atmospheric air, the adion 
of the flame- gases is suppressed. 

Volatilisation may also be avoided in a covered crucible 
if it is very large, and if the bottom only is touched by 
the point of the flame. But as, on evaporating the nitric 
acid, some of the substance generally adheres to the 
8i4cs, this method of ignition is impraAicable. We have 
now indeed found that — 

I. On igniting antimonic acid with access of air a con- 
stant weight is quickly reached. 

a. The antimony oxide thus obtained corresponds to 
the formula Sb804. 

But 1 have further effeAed some determinations of 
antimony as tetroxide with previous precipitation of the 
antimony as sulphide, the results of which demonstrate 
tbe accuracy of the method. 

In order to prevent an oxidation of the precipitate 
along with the filter, the washed antimony sulphide was 
riosd with a little water into a small capsule, and the 
panicles still dineing to the filter are dissolved in hot 
ammonium sulphide, which is easily effe<2ed whilst the 
precipitate is moist. The solution is evaporated to dry- 
ness in a weighed porcelain crucible ; the main bulk of 
the precipitate is also rinsed into the crucible, and again 
evaporated. The precipitate is then moistened with 
coocentrated nitric acid and oxidised with fuming nitric 
acid, osing instead of the cover a watch-glass, which is 
then rinsed off. The solution is then evaporated to dry- 
ness, the sulphuric acid which has been formed is 
cantioQsly driven off by heat, and the residue strongly 
heated in an open crucible until the weight is constant. 
Tbe method is, in accuracy, at least equal to the other 
methods of determining antimony, and surpasses them in 
simplicity and promptitude of execution. 

In presence of small quantities of antimony, when the 
inaccuracies attending weighing a precipitate along with 
the filter have a considerable effeA upon the result, 
Bnnsen's old method may be considered preferable to all 
others. — Ztit* Anal, Chtm., xxxiv., p. 171. 



159 



NOTICES OF BOOKS. 



PoUoHS : Thiif EfftcU and Detiction, A Manual for the 

Use of Analytical Chemists and Experts. With an 

Introdudory Essay on the Growth of Modem Toxico* 

lonr. By Albxandbr Wynter Blyth, M.R.C.S., 

F.LC, F.C.S., &c., Barrister-at-Law, Public Analyst 

for the County of Devon, and Medical Officer of Health 

and Public Analyst for St. Marylebone. Third Edition, 

Revised and Enlarged. With Tables and Illustrations. 

8vo., pp. 724. London : Charles Griffin and Co., Ltd. 

1895, 

Wk have here before us an excellent treatise, instrudive 

and suggestive, not merely to chemical experts and 

students, to medical praditioners and pharmacists, but to 

chemical mannfaAurers, to legislators, and lawyers, and, 

if we may presume to make the suggestion, even to 

novelists and play-wrights and to the writers of the daily 

press. 

The work has already passed through two editions, but 
it has undergone such enlargements and revisions—in 
accordance with the advance of science — that it may 
fitW be treated as a new publication. 

In the ** Old Poison Lore '* Mr. Blyth holds that the 
traditions of poisons which, though producing no imme- 
diate dffed, might yet prove ultimately fatal, were more 
than fables. Have we not a too familiar instance of this 
phenomenon in the bite of a rabid dog ? Our author 
thinks that " the Asiatic poisoners were well acquainted 
with the infedious properties of certain malignant 
It might be added that they seleded poisons 



whose effeas might simulate the symptoms of nataral 
disease. 

In connexion with the detedion of poisoning, we may 
mention that it is to the Popes that science was indebted 
for the sandion, in the Fifteenth Centnry, to dissed 
human subjeds. 

The account given in the following chapter of the 
developnient of our modem methods for the detedion of 
poisons in the body. As an epoch in toxicology U 
mentioned the discovery of the Marsh method of deted- 
ing arsenic, which '* for the first time rendered the most 
tasteless and easily administered poison in the world at 
once the easiest of detedion.'* 

We come to that difficalt qoestion^the definition of 
poison. The author comments on the British law 
(Criminal Consolidation Ad, x86i) the German statute, 
and the present French law. The author's own definition 
of poison, as given in the first edition of the present work, 
Is— **A substance of a definite chemical composition, 
whether mineral or organic, may be called a poison if it 
is capable of being taken into any living organism and 
causes by its own inherent chemical nature impairment 
or destrudion of fundion.** 

As to the classification of poisons, the anthor admits 
that no perfed classification is yet possible. 

In considering the statistics of poisoning, the author 
holds that the higher the mental development of a nation 
the more likely are its homicides to be caused by subtle 
poison, and its suicides by chloral, morphine, or hemlock. 
The two leading poisons in South Britain for the decade 
ending 1892 are opiates and lead ; carbolic acid coming 
third. Out of xooo attempts in France to injure or destroy 
human life by poison, arsenic accounts for 331 and phos- 
phorus for 301— two of the most painful poisons ordin- 
arily available. 

The connedion between toxic adion and chemical 
composition is discussed at some length. The researches 
of Dr. Blake and of Rabuteao on the comparative toxic 
adion of metals seem to have been overlooked. The 
more attention has been given to the organic poisons. 
The author considers that the occurrence of hydroxyl 
appears frequently to confer poisonous properties upon 
the substance. In aromatic compounds tne toxic power 
increases with the number of hydroxyls. 

The substitution of a halogen for hvdrogen is apt to 
produce narcotic substances. This sedion, and especially 
the general theory of Oscar Loew (p. 39), deserve the 
most careful study, experimental if possible. 

The chapter on ** Life Tesu "—the identification of 
poisons by experiments on animals— has been greatly 
abridged, since, in consequence of the deplorable ** Vivi- 
sedion Ad," this method of research is pradically out of 
the reach of British chemists and physiologists. If the 
Society for the Advancement of Medicine by Research is 
still in existence, we would ask why it has never organ- 
ised a laboratory, say at Calais, Boulogne, or Antwerp, 
where such experiments might be performed ? 

As regards the identification of the several poisons, the 
author gives some most useful precautions, and pieces of 
information which the expert may be suddenly called to 
produce. Thus, it was adnally asked of a witness in the 
Tawell case, whether hydrocyanic acid might not have 
been introduced by eating apples. Now, Mr. Blyth men- 
tions here that apple-pips contain 0*035 per cent of HCN ! 
Attempts have in like manner been made to explain the 
presence of oxalic acid in the matter vomited by a patient 
and found in the stomach of a corpse by the hypothesis 
that the vidim had been eating rhubarb pie or a salad 
containing sonel. 

A real difficulty arises in a case of nicotine poisoning 
if the deceased has been a heavy smoker or tobacco- 
chewer. How much nicotine may be introduced in this 
manner into a human subjed it might be impossible to 
decide with any accuracjr. 

Under ** Arsenic," we find a recapitulation of the salient 
points of the Maybrick casei 



i6o 



Chemical Notices from Foreign Sources. 



1 CmbmicalNbwi, 
I Sept. 27, 189s. 



Want of space does not allow US to extend our notice 
of Mr. Wynter Blyth*s work, but we may decidedly re- 
commend it to every professional man who has not already 
familiarised himself with its contents. 



Camhridgi Natural Science Manuals, Physical Series. 
General Editor, R. T. Glazebroor, M.A., F.R.S., 
Assistant Diredor of the Cavendish Laboratory, Fellow 
of Trinity College, Cambridge. Solution and Electro- 
lysis. By William Cecil Dampier Whbtham, M.A., 
Fellow of Trinity College, Cambridge. Cambridge : 
The University Press. 1895. Pp. 296. 
As a clear compad^ exposition of solution and eledrolysis 
as now understood this little work will be found very 
valuable to students of physics and chemistry. After an 
account of the general properties of solution, the author 
goes on to describe the solutions of gases in gases, of 
liquids in gases, and of solids in gases. 

In the third chapter the author proceeds to consider 
solutions in liquids, and solubility, snowing the solubility 
of gases in liquids ; the measure of solubility ; Henry's 
law, the solutions of gases in saline solutions ; the solu- 
bility ol liquid and of solids in liquids ; the influence of 
pressure and of temperature ; the analogy between solu- 
tion and evaporation; the solubility of mixtures, and 
solubilities of mixed liquids; followed by a Table of 
Solubilities. 

In the fourth chapter we have an account of the prin- 
ciples of dififusion and dialysis. Mr. Whetham then pro- 
ceeds to treat of the freezing-points of solutions, the 
determination of molecular weight, of cryohydrates, and of 
the melting-points of alloys. 

The vapour pressures of solutions are discussed in the 
sixth chapter, after which, in the seventh, eighth, and 
ninth chapters, the author enters upon the eledrical pro- 
perties of solutions. Here the reader meets with an ac- 
count of the ions, their migrations and velocities, the 
theory of dissociation, and eledrical endosmose. 

In the tenth chapter is shown the connexion between 
eledrical and other properties, such as chemical adivity 
and osmotic pressure. 

In the concluding chapter we find the theories of elec- 
trolysis, an interesting account of the colours of saline 
solutions, the general case of chemical equilibrium. 

There is an appendix on freezing-points and a table of 
the eledro-chemical properties of aqueous solutions. 

The work will be found accessible to a wider circle of 
minds than might have been at first sight expeded. 



*' Sanitas.** How to Disinfect. A Guide to Pradical 
Disinfedion during Cases of Infedious Illness, and in 
Every- day Life. London : The Sanitas Company, 
Limited. 
This pamphlet may be considered as essentially an 
abridgment of Mr. Kingzeti's *• Nature's Hygiene "—a 
work which we have had much pleasure in examining. 
The author adduces testimonies in favour of the Sanitas 
preparations from the most varied authorities, from 
eminent physicians and surgeons down to sporting 
charaders and dog-fanciers. He declares war against 
the didum that every disinfedant, to be efficacious, must 
be poisonous. He contends that the " Sanitas " prepara- 
tions aie of the highest value, not merely in combating 
cholera, yellow fever, diphtheria, &c., but in destroying 
or banishing aphides and other scourges of our gardens 
or orchards, though he makes no mention of their success 
or failure in the treatment of the phylloxera. The Sanitas 
oil is recommended for banishing mosquitoes or other 
analogous pests. We should like to ask Mr. Kingzett 
whether he has ever made a comparative trial with the 
extrad of Marsh-rosemary {Ledum pahntre)^ which has 
done such good service against mosquitoes and sand-flies 
{e.g,^ Simulium columbaczense) in every climate where it 
has been tried. 



It must be remarked that the Sanitas Company, Limited, 
do not confine themselves to the manufadure of the pre- 
parations patented under the name of '* Sanitas." They 
are manufadturers of, and dealers in, hydrogen peroxide, 
a mercuric badericide, corrosive sublimate pellets, and 
sulphur fumigating candles, and even of carbolic acid, of 
chlorides of lime and zinc, the permanganates, and of iron 
and copper sulphates. 

For disinfedants, indeed, the field is still large, if we 
may judge from the recent prevalence of epidemics. 



CORRESPONDENCE. 



[DISINFECTANTS. 

To the Editor of the Chemical News. 

SiR,~The remark with which Dr. Rideal seems dissatis- 
fied was applied to the words which he quotes in hit 
letter. He cannot, of course, deny that sewage contains 
phosphates, precipitable by salts of iron, aluminium, &c. 
He must admit that his words, ** to recover the phosphate 
by using the sludge as a fertiliser," were open to the con- 
strudion which I placed upon them, as referring to the 
total phosphates in the sewage sludge of what origin 
soever, and he is of course well aware that valuable 
quantities of phosphates may be found in sludges to 
which neither animal charcoal nor mineral phosphates 
have been added. Animal charcoal is now rarely, if ever, 
used in the treatment of sewage. 

Utterly disclaiming any intention to disparage Dr. 
Rideal's work, I am, &c.. 

Your Reviewer. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NoTB.— AH degrees of temperature are Centigrade unless otherwit* 
ezpreued. 

Comptes Rendus Hebdomadaires des Seances^ de VAcademit 
des Sciences. Vol. cxxi.. No. 7, August 12, 2895. 
Special Microscope for the Observation of Opaque 
Bodies.— Ch. Fremont. — The author, after pointing out 
the defeds of previous devices, e.g.^ that of Lieberkiihn, 
describes his invention, which consists in illuminating the 
interior of the tube of the microscope through the objed- 
glasses. The arrangement cannot be described intelligibly 
without the accompanying figure. The arrangement is 
said to afford a vertical illumination, very intense and 
perfe^ly defined, and to be especially adapted for micro- 
photography. 

Potassium Derivatives of Qainone and Hydroqui- 
none.— Ch. Astre.— The author has studied the adion of 
potassium upon quinone in ethereal or benzenic solutions 
and upon hydroquinone in a benzenic solution. The 
author, in concert with M. Ville, purposes extending his 
observations to other metals. 

No. 8, August 19, 1895. 

On Matches with Explosive Compositions. — T. 
Schloesing.— The author's results impress upon us the 
necessity of avoiding accidental ignitions during the 
operations after drying. We may indeed proscribe pastes 
of antimony and lead, although their compounds figure 
in all the pastes whether ancient or of recent invention, 
but we cannot proscribe phosphorus, and if this body | re- 
duces the fumes of its acid in the workshops we lose— at 
least in part— the essential advantage of the suppression 



Cbbmical News, I 
Septa?, 1895. I 



Chemtcal Notices from Foreign Sources. 



161 



of white phosphorus. Hence the substitution of ex- 
plosive pastes for pastes with white phosphorus is not so 
simple a matter as we may be tempted to believe. 

Researches oa the Compouads of Mercury Cya- 
nide with Chlorides. — Raoul Varet. — Mercury cyanide, 
when a^ng on metallic chlorides, forms compounds of the 
type aHECyaM"Cla.iiHaO. The author has made a thermo- 
chemicsl study of the mercury and sodium chloro- 
cyanide, the corresponding compounds of mercury and 
ammonium, mercury and barium, mercury and strontium, 
mercury and calcium, mercury and magnesium, mercury 
mnd sine, and mercury and cadmium. 

Thermic Researches on Cyanuric Acid. — Paul 
Lemonlt.-— A thermo-chemtcal study, not suitable for ah- 
stradion. 

Combustion-Heat of Certain ^•Ketonic Ethers.^ 
J. Ottinchant. — Not suitable for abstraAion, 

Determination of the Heat Liberated in Alcoholic 
Fermentation.— A. Bouffard.— The heat liberated is be- 
tween 34 and 32 cals. We must not calculate in the 
construaion of refrigerators npon 71 cals. 

On the Qum of Wines. — G. Nivi^re and A. Hubert. 
— The authors, in opposition to Pasteur and Bechamp, 
show that there exists a marked difference between the 
gum of wines and eum-arabic. The latter, when 
oxidised with nitric acid, only yields 35 per cent of mucic 
acid, whilst the gum of wine yields 70 to 75 per cent, If 
we boil the gum of wine with dilute sulphuric acid it 
yields no arabinose, but it is transformed into galadose, 
whilst reduAive agents change it into dulcite. Gum- 
arabic, if heated with dilute sulphuric acid, yields arabi- 
nose, and with redudive agents it forms arabite. 

No. 9, August 26, 1895. 

Heat of the Solution and of the Formation of 
Sodium and Potassium Cyanurates.— Paul Lemoult. 
— The author's studies do not reveal any essential differ- 
ence between the sodium and potassium salts. They 
show, further, that these salts are not decomposed by 
water. 

On ApicoUted Fermentation, and on the Influence 
of Aeration in Elliptical Fermentations at High 
Temperatures. — M. Rietsch and M. Henselin. — The 
refrigeration of musts below 30° has more decided effeds 
than aeration. The combination of these two agencies 
gives the best pradical results ; this combination is the 
more indicated the more concentrated are the musts. 

Utensils of Aluminium.— M. Balland.— The author's 
investigations have been undertaken with reference to 
military uses, for which the low specific gravity of alumi- 
nium is especially suitable. In the ordinary conditions of a 
soldier's life aluminium utensils offer a sufficient resistance 
to wear and fridion, to the adion of foods and of potable 
liquids. The metal takes a clouded appearance, but its 
weight after four months' use does not vary appreciably. 
Their contad with foods, &c., is of brief duration. On 
prolonged contad the adion is more considerable. The 
behaviour of impure samples of aluminium— containing, 
as sometimes occurs, as much as 8 per cent of foreign 
matter— cannot be inferred from the author's experi- 
ments. Aluminium vessels should never be cleansed with 
soda, and solderings should be avoided as much as 
possible. 

No. 10, September 2, 1895. 

Presence of Argon and Helium in Certain Mine- 
ral Waters.— Dr. Ch. Bouchard.- (See p. 252). 

Combination of Magnesium with Argon and 
Helium.— (See p. 153). 

Researches on the Compounds of Mercury Cy- 
nnide with the Bromides.— Raoul Varet. — The author 
has continued his researches on the combinations of mer- 
cury cyanide with the bromides of the alkaline and 
alkaline-earthy metals, of sine and cadmium. The re- 



sults, thermo-chemical data, do not admit of useful 
abridgment. At ordinary temperatures the solutions of 
the bromo-cyanides, mixed with the picrate of the same 
bases, yield, in course of time, traces of an isopnrpurate. 
Mercury cyanide does not ad upon tindure of litmus. 
On the contrary, the cyanides of the alkaline and 
alkaline-earthy metals turn the red tindure to a bine. 
The solutions of the bromo-cyanides, contrary to the 
chloro-cyanides, turn litmus slightly blue even in the 
cold. 

Formation of Hydrogen Selenide.— H. Pdadon.— 
This paper requires the accompanying diagram. 

Adtion of Carbonic Acid, of Water, and of Al- 
kalis upon Cyanuric Acid and its Dissolved Sodium 
and Potassium Salts. — Paul Lemoult. — This paper, 
essentially thermo-chemical, does not admit of useful 
abstradion. 

The Eclipsoscope, an Apparatus for observing 
the Chromosphere and the Solar Protuberances.— 
Ch. V. Zenger. — The description of this instrument 
should be accompanied by diagrams. 



Bulletin de la Societi d^Bncouragtmint pour Vlnduslrii 
Nationali, Series 4, Vol. x.. No. 113. 
Report presented by M. Jordan on behall of the 
Committee of the Chemical Arts on F. Osmond's 
Paper entitled **A General Method for the Micro- 
graphic Analysis of Carbon Steels." — The method in 
question was in the first place due to Dr. H. C. Sorby, of 
Sheffield, who in 1864 laid before the British Association 
micro-photographs of various sorts of steel and iron, and 
elaborated a process for the study of the sedioos of the 
metals as preferable to fradures. Prof. Maters, of Ber- 
lin, in 1878, seems to have independently taken up the 
same line of research. MM. Osmund and Wertb, of 
Cieusot, further developed microscopic metallography. 
The former, in a paper here inserted, summarises the re- 
sults hitherto obtained, and gives an account of the pro- 
cedure to be adopted. In polishing the sedions the author 
was induced to make use of liquorice* water in conjundion 
with jewellers' rouge and precipitated calcium sulphate, 
and K>und that it coloured certain constituents, leaving 
others untouched. After the polishing the adion is con- 
tinued by means of acids, halogens, principally nitric 
acid and tindure of iodine. The charaderistics of iron 
and steels, with their peculiar constituents, ferrite, mar- 
tensite, troostite, cementite, and sorbite, are shown in an 
illustration. 

Report presented (by M. Jordan on behalf of the 
Committee of Chemical Ant on the Researches of 
Mr. Hadfield on the Alloys of Iron with Silicon, 
Aluminium, and Chrome.— Mr. Hadfield's researches 
on chrome-steels are pointed out as of exceptional prac- 
tical importance. 

No. 114. 

Elimination of Foreign Metals during the Produc- 
tion of** Best Selected" Copper.— Allan Gibb. — From 
the InstituU of Michanical Enginars, 

Preparation and Properties of Pure Melted Mo- 
lybdenum. — Henri Moissan. — The substance of this 
paper has already been noticed in connedion with the 
CompUs Rendus, 

No. X15. 

The meeting of June 28th, 1895, was taken up with a 
notice of the prizes awarded for various inventions. 
Very few of these interest the chemist. F. Osmond ob- 
tained a prize of 2000 francs for a study of the physical 
Jropeities of alloys in common use, especially steels, 
ules Garcon obtained a prize of 500 francs for an account 
of the machinery employed in bleaching and dyeing tex- 
tile fibres. The prize for the purification of potable 
waters, amounting to 2500 francs, has been divided 



l62 



Chemical Notices from Foreign Sources. 



{Chbmical Ntws, 
Sept. 27» 1895* 



ftmoDg four candidates— MM. Tellier, Lacroix, Schlum. 
berger, and Meignen. Tellier proposes to sterilise water 
by the combined aAion of heat and pressure. Lacroix 
decomposes water by the eledric current, liberating hy- 
drogen, and generating ozone and '* ele^rolytic oxygen.** 
Schiumberger passes the water over pumice saturated 
with alnminium benzoate, and then over charcoal coated 
with manganese peroxide ; this double filtration is said to 
destroy the greater part of the organic matter and almost 
all the baAeria. The process of Meignen is not 
described. 

Communication by C. Bardy on the Process for 
Treating Crude Turpentines.— Gabriel Col.— The ad- 
vantages of this process depend entirely on the strudure 
of the plant employed. 

The Determination of Small Quantities of Arsenic. 
— Ad. Camot. — Noticed under the Comptes Hindus. 

Redndtion of Silica by Coke.— H. Moissan.— Also 
noticed under CompUs Hindus, 

MISCELLANEOUS. 

Special Manures.— Messrs. W. H. and L. Collingridge 
have just published a book on '* Special Manures for 
Garden Crops," by Dr. A. B. Griffiths, F.R.S.E., F.C.S. 
The work contains about eighty analyses of plant-ashes 
(which represent over eighteen hundred separate weigh- 
ings), performed by the author and his pupils. The work 
is quite unique and original. 

Serpent Venoms. — According to Professor T. D. 
Fraser {Transactions of thi Royal Society of Edinburgh), 
the venom of the cobra is sixteen times more powerful 
than that of the rattle-snake (Crotalus horridus). The 
** diamantine snake " of South Australia — a species not 
sufficiently identified — is intensely virulent, as of its venom 
0*00x5 grm. is equivalent to 0*004 &^* of rattle-snake 
poison. 

y^CEtf70NEtf — Answering all requirements. 
A.OTT> JV-CIEJTIO—Pureit and sweet. 

— BOIR JLOIC— Cryst. and powder. 

— ^ CITIRIC— Cryit. made in earthenware. 

— Gh-A-XiXilO— Fro™ !>«•* Chinese galls, pure. 

S.A.IilCTTIilO-By Kolbe't process. 

— t T j^ItsTZfTIO—For Pharmacy and the Arts. 

LIQUID CHLORINE 

(Compretied in steel cylinders). 

FORMALIN (407^ CHaO)— Antiseptic and Preservative. 

POTASS. PERMANOANATB-Cryst., large and imall, 

SULPHOCYANIDE OF AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THE ARTS 

Wholesale Agents— 

A. ^ M. ZIMMERMANN, 

6 A 7, CROSS LANE LONDON, E.G. 



NOTICE TO ANALYSTS AND LABORATORY 
DIRECTORS. 

Best METHYLATED SPIRIT, manufac- 
tared by A. & J. WARREN, Wholesale DruRgisti, Dealers 
in Chemicals for Analytical Work, and Methylated Spirit Makers, 

a and 24, Redcliff Street, Bristol. For Four- pence a Pamphlet on 
ethylated Spirit, written by Algernon Warren, is obtainable from 
the PabUsher, ). W. ARRowsMrtH, Quay Street, Bristol; and 
SmrsiM, MAitBALL, 1Umiltoii» KiMT, a&d Co., Ltd., London. 



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CHEMICAL ANALYSIS OF OILS, FATS, WAXES, 

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Crbmical NlWt, I 



Action of Nitric Add on certain Salts. 



163 



THE CHEMICAL NEWS. 

Vol. LXXII.. No. 1871. 



THB 

ACTION OF NITRIC ACID ON CERTAIN SALTS.* 
By H. A. AUDBN, B.Sc, and O. J. FOWLBR, If .Sc. 

Tbb experinraU here recorded are part of a systematic 
iavesiigation into the conditions of stability of the oxides 
of aitrogcn. They are by no means complete, hot the re* 
tnltt so far obtained appear to be of sufficient interest to 
warrant a preliminary notice. 

The rea&ioos of nitric oxide have so far alone been 
■todied. The gas was prepared by Emrich's method, vix., 
the interaaion of sodiam nitrite, strong sulphuric acid, 
and mercury. The mixture was kept in continual agita- 
tsoo by a specially contrived stirrer worked by a turbine. 
la this way a regular stream of gas is obtained, which 
aaa^fsis showed to be of a high degree of purity. 

In order to study the adion of nitric oxide upon the 
talu seleded, a weighed amount of the salt was placed 
in a boat contained in a Lothar Meyer constant tempera- 
tore furnace. Bv means of a thermostat, also devised by 
Lothar Merer, the temperature can be kept to within one 
degree. Temperatures above the range of an ordinary 
instrument were measured by means of a high tempera- 
tnre thermometer, conitruded by Max Kaehler and 
Martini, of Berlin, which would give accurate readings to 
over 400^ The salt was heated gradually in a stream of 
nitric oxide and the phenomena noted as the tempera* 
tore rose ; the salt was weighed at different intervals of 
ttmperatoro, so that it was possible to tell at what tem- 
perature readion began, and at what point it attained a 
Maximum velocity. 

So far. oxy-aalts have been chiefly studied. It was 
tbooght that by comparing their behaviour under the 
above conditions some light might be thrown on their 
•lability and thence on their constitution. One or two 
oxides were fixed examined, the results agreeing with 
those of Sabatier and Senderens, i^,, PbOa forms a basic 
nitrate of lead when heated in nitric oxide; the adion 
b^ins at a temperature as low as 25^ but does not attain 
its maximum till over 130^. 

MnOa behaves similsriy, but the change is not so rapid 
m» in the case of PbOat probably owing to the smaller 
•lability of manganese nitrate. The change is most rapid 
at ax6°. In neither case with a peroxide are any but 
traces of a nitrite formed. 

Silver oxide, however, at any rate if at all moist, yields 
a mixture of almost equivalent parts of silver nitrite and 
aaecallic silver at the ordinary temperature. At higher 
temperatures, with the dry oxide, nitrate and metallic 
silver are formed almost entirely. 

Silver permanganate begins to be attacked at the or- 
dinary temperature, and at 80° the alteration is very 
rapid. On analjrsis of the residue it was found to consist 
of metallic silver, silver oxide, silver nitrate, and man- 
ganese dioxide. Very little, if any, manganese nitrate 
was formed. 

Potassium permanganate is much more stable than the 
•ilver salt. It is not appreciably attacked till over xoo*, 
and the increase in weight becomes rapid at igo^. The 
imaidoe on moistening was not alkaline, and no man- 
ganese could be dissolved out. The potassium is con- 
verted into nitrate and the manganese into oxide. 

Interesting differences were noted in the behaviour of 



• RMd btfor* the BHtiih Asiociatko (SsAion B), Ipiwkb 
MMtiag, 1895. 



Other silver and potassium salts, notably the chlorates 
and iodates. 

Potassium chlorate is attacked by nitric oxide at the 
ordinary temperature, chlorine being evolved in consider- 
able quantitv, and nitric peroxide being formed. The 
gaseous produd was condensed in a tube immersed in a 
freexing mixture, and the percentage of chlorine in the 
brown liquid obtained was determined. It was found to 
be much in defisd of that required to form nitiosyl or 
nitroxyl chloride, so that the readion does not consist 
simply in the formation of an oxy*chloride of nitrogen* 
On analysis of the residue in the boat no chloride of 
potassium was found to be present. Nitrate was ibnaed* 
and also a slight trace of perchlorate. This seems to be 
dired proof that in potassium chlorate the potassium and 
chlorine are separate. 

With barium chlorate a similar readion took place. 

With silver chlorate (prepared according to Stas's 
method), chlorine was given off, but a considerable 
amount of silver chloride was also formed — nearly one- 
third of the silver present being found as chloride. This 
may be due to a difference in constitution between the 
chlorates of silver and of potassium, or to a difference in 
stability of the produds of readion. That some difference 
of constitution exists between the silver and potassium 
salts appears to derive confirmation from the behaviour of 
their iodates when treated with nitric oxide. 

Potassium iodate, heated to 80P in nitric oxide, begins 
to give off iodine, and the readion becomes rapid at 
zio^ crystals of iodine condensing on the cool portion of 
the tube. No trace of iodide, however, is formed, as 
is shown by there being no liberation of iodine on acidi- 
fying a solution of the residue after adding some potas- 
sium iodate. The residue is not alkaline, the poUssinm 
being converted into nitrate, recognised by the evolution 
of ammonia when the residue is warmed with sinc-dost 
and caustic soda. 

Silver iodate, on the other hand, is stable up to a rather 
higher temperature than the potassium salt, and when 
heated above this temperature, about xio^, no trace of 
iodine is given off, but all the silver is converted into 
iodide, none being dissolved out b^ water, and the yellow 
residue being insoluble in dilute nitric acid. 

The perchlorates and periodates which have been ex- 
amined show themselves more stable than the corres- 
ponding chlorates and iodates. 

Potassium perchlorate does not begin to be attacked 
till above aoo*. A small quantity of chloride was found 
in the residue, but the high temperature (over 300^ em- 
ployed mav have induced secondary changes. The potas- 
sium for the most part is converted into nitrate, there 
being considerable lou of chlorine. 

Barium periodate is stable up to aoo*', when iodine is 
given off. On heating to 388^ much iodine is given cff, 
and barium iodide found in the residue. 

Of the salts so far examined, chromates have shown 
themselves the most stable, being analogous in this resped 
to the sulphates. 

Lead chromate was unaltered at a temperators esoeod- 
ing4oo*. 

Silver chromate did not suffer appreciable change titt 
above 300°. Metallic silver was found to be present in 
the residue as well as silver nitrate. The chromium was 
all converted into the sesquioxide. Some amount of 
nitrite of silver was also formed. Silver sulphate is only 
slightly attacked at the highest temperature of the 
furnace. 

It was found in certain cases, #.£., with lead nitrate, 
that the intermixture of a decomposable oxide, #.f ., PbOs 
or MnOa with the salt caused the latter to be attacked at 
a temperature below that at which adion begins with 
either the salt or oxide taken separately. 

Bxperimenu have also been in progress on the inter- 
adion of nitric oxide and various gases, but the lesults 
are not yet quite complete enough for publicatioii. 



1 64 



Data for the True Atomic Weight of Carbon. 



\ 



Chemical h^ws. 



THE FORMATION AND PROPERTIES OF A 

NEW ORGANIC ACID.* 

By HENRY J. HORSTMAN FBNTON, M.A 

When tartaric acid is oxidised under certain conditions 
in presence of a ferrous salt a substance is produced 
which ads as a powerful reducing agent, and which gives 
a beautiful violet colour with ferric salts in presence of 
alkali. This substance has after considerable difficulty 
been isolated, and proves to be a dibasic acid having the 
formula C4H4O6.3H2O. 

The constitutioo of this acid is now under investiga- 
tion. 

Heated with hydrogen iodide it gives succinic acid, 
racemic acid being an intermediate produd. Bromine in 
presence of water oxidises it quantitatively to dioxy- 
tartaric acid. Heated with water it is resolved into car- 
bon dioxide and glycoUic aldehyd. 

Thrs aldehyd has been obtained as a viscid liquid, pure 
except for a trace of ether ; and, on removing the latter 
by heating in a vacuum, the aldehyd undergoes polymer- 
isation, a sweet-tasting solid gum being the result. Ana- 
lysis and molecular weight determinations show that this 
gummy substance has the formula CfiHxaOe {Journ, Chem, 
Soc, 1894, 899 ; X895, 48 and 774). 

Further observations have recently been made as to 
the conditions under which this new acid may be obtained 
from tartaric acid. The presence of a firrous salt is 
essential. Ferric, manganous, and various other salts 
have been tried with negative results. 

If moist ferrous tartrate be exposed to the air for a short 
time a certain quantity of the new acid is produced, and 
may be indicated by the charaderistic violet colour given 
when caustic alkali is added. The effed is much more 
intense if the exposure be made out of doors, and the in- 
creased result was at first attributed to some constituent 
of the fresh air (/.^., hydrogen dioxide ; ozone seems to 
be inoperative). But later experiments show conclusively 
that light is the cause. Air which has been purified by 
passing through potassium iodide and caustic potash 
solutions gives an efifed about equal in intensity to that 
produced by fresh external air, if the exposure to light is 
the same in both cases. That oxygin (or some oxidising 
agent) is essential is shown by the fad that exposure in a 
vacuum, even to bright sunlight, gives a negative result. 



DATA FOR THE ASCERTAINMENT OF THE 

TRUE ATOMIC WEIGHT OF CARBON. 

By J. ALFRED WANKLYN. 

In December, 1893, 1 wrote in the Philosophical Maga* 
Mine : — 

*'An investigation which has occupied me for the 
greater part of the year has yielded the following result. 
There is a series of hydrocarbons the successive members 
of which rise in molecular weight — notbyCH2 = T4 — but 
by i (CH2) = 7. If this result cannot be overturned, the 
consequence follows that the atomic weight of carbon 
is 6." 

The series concerning which I wrote at the close of the 
year 2893 ^^^ ^^^ hydrocarbons existing in Russian 
kerosene imported into this country. That series would, 
according to the prevailing knowledge of the day, be 
termed a series which was only imperfedly understood. 
Continuing our work, my colleague Cooper and myself 
have recently published (Philosophical MagaMine^ August, 
Z895) a parallel investigation with a parallel result, 
given by a series of hydrocarbons which the knowledge 
of thfe day pronounces to be comparatively well explored 

* Read before the British association (Sedion B), Ipswich 
Meeting, 1S95. 



and well understood. The series is the marnr^n aeries, 
which is now regarded as the backbone of organic 
chemistry. 

The paper published last month in the Philosophical 
MagaMine contains a concise statement of our work, and 
we proceed to quote from it as follows : — ... 

The first term of the marsh gas series which figures in 
our table is the fifteenth member of that series. In an 
admirable paper of Schorlemmer's, published in the 
Journal of the Chemical Society for the year 2863, a liquid 
is described under the name of hydride of heptyl, which 
we believe contained at least 50 per cent of our marsh xv. 
(formula CijHx^). Quoting from that paper we find that 
a combustion of the liquid gave 83*93 per cent of carbon, 
26*13 per cent of hydrogen, and the determination of 
vapour density 3*59, which is a figure between that 
required for hydride of heptyl and our marsh xv., and 
which indeed approaches nearer to that required by 
marsh xv. than to the figures required by hydride of 
heptyl. 

The figures are theoretical V.D. of marsh xv. 333*597 ; 
theoretical V.D. of heptyl hydride 3*455. Obviously 
therefore the figures obtained by Schorlemmer, 3*59, 
agrees better with our view than with that held by him- 
self thirty years ago. 

As I hold that the only datum given in Schorlemmer's 
paper which is valid as a piece of evidence capable of 
deciding between the two formulae is the V.D. deter- 
mination, I hope I may be pardoned for going over 
Schorlemmer's calculation, the correAness of which I 
am able to confirm. I make, however, this note, there is 
no mention made of the size of the inevitable air-bubble 
in the Dumas-determination, and if we suppose that this 
air-bubble was of the usual size when the workmanship 
is excellent (as Schorlemmer's workmanship always was), 
the corredion for the air-bubble would bring Schor- 
lemmer's figures very close to marsh xv. 

A consideration of all the circumstances of the case 
leads me indeed to the belief that Schorlemmer's hydride 
of heptyl of the year 1863 consisted mainly of marsh xv., 
mixed with hydride of heptyl. 

The main body of Schorlemmer's paper, which I am at 
present quoting, is occupied with an account of the 
chlorination of the hydrocarbon and the various derivatives 
of one of the produds of the cblorinatioa. It is an 
admirable piece of chemical workmanship, and deserves 
proper appreciation. 

There are two classes of readion in organic chemistry, 
viz., the complete and the incomplete. 

Chlorination of such a body as marsh xv., or heptyl 
hydride, is notoriously an incomplete readion. This 
fad becomes very apparent in Schorlemmer's account of 
the operation. It is impossible to take a quantity of the 
hydrocarbon and transform the whole of it, or anything 
like the whole of it, into a monochlonde. Only a portion 
of the hydrocarbon undergoes chlorination in this opera- 
tion and the *' unattacked hydride," as Schorlemmer 
says, was distilled off after the termination of the 
chlorination. The monochloride was then separated by 
fractional distillation from the accompanying di-chloride, 
and from the still more highly chlorinated produds which 
are the inevitable companions of the mono-chloride as 
yielded by the process of chlorinating a hydrocarboo. 
The mono-chloride (which is described as a liquid boiling 
at 150°) does not appear to have been submitted to 
analysis, but was employed in the preparation of the 
acetic ether by readion upon acetate of potash. Great 
difficulty was experienced in pushing the readion to com- 
pleteness, and, furthermore, only a portion of the monc- 
chloride underwent transformation into the acetic ether. 
The olefine heptylene as well as acetate of heptyl are 
described by Schorlemmer as arising from the readiofl 
upon acetate of potash. 

The acetate of heptyl described by Schorlemmer wai 
therefore derived from the original hydrocarbon by two 
incomplete readions, and is not a fair representative of 



'"SS'^1^7*' ) Formation of Citric Acid by the Oxidation oj Cane-iugar. 



165 



the whole of the original hydrocarbon. The acetate was 
analysed and its analysis agreed with the forroala for 
acetate of heptyl. It was also converted into the corres- 
ponding alcohol by a process which is known to be com- 
plete when applied to the acetate. The alcohol was 
also converted in a thoroughly satisfa^ory manner into 
the iodide, and both alcohol and iodide were analysed 
with good resalts, the iodide especially being beautifully 
in agreement with the theory. When these results are 
fairly considered they indicate the probability that some 
portion of the original hydrocarbon consisted of heptyl- 
hydride, but they afford no ground for the conclusion that 
the whole or even the greater proportion of it consisted of 
that hydride. There is a curious piece of evidence 
pointing in the other diredion. The olefine (which 
accompanies the acetate of heptyl) was investigated. It 
was sealed up with hydriodic acid and heated to the 
boiling point of water for twelve hours and converted 
Into an iodine compound, which on analysis was found 
to contain only 5573 per cent of iodine instead of 56*19 
required by the iodide of the heptyl series. 

The circumstance that the other iodide gave almost 
exadly the theoretical result, viz., 56*18 per cent of 
iodine, lends importance to this discrepancy, which 
Schorlemmer does not in any way explain. 

A by no means unlikely explanation of the discrepancy 
is that the iodine compound was a mixture of the deriva- 
tive from our marsh xv. with the derivative from hexyl> 
hydride. 

In criticising this work of Schorlemmer's nothing is 
further from my intention than to belittle it. A very 
important general U6t is established by it and by the 
researches of Cahours and Pelouxe and Carius. That 
fad it, that one atom of hydrogen in the marsh gas 
series of hydrocarbons is replaceable by chlorine, which 
in its turn suffers replacement by other radicals so as to 
yield the alcohol, the mercaptan and the various ethers. 
Until, however, the chlorination process has been much 
improved it cannot be valid as a method of distinguishing 
between heptyl-hydride and the fifteenth term of the 
marsh gas series. 

In due time we exped to exhibit the intermediate 
alcohols and their various derivatives, but at present we 
have no intention of taking in hand this branch of the 
investigation. We are at present engaged with the 
physical side of the subjed, and with only such chemical 
changes as do not involve the destruAion of the hydro- 
carbons. 

Inasmuch as the process by which we have been able 
to separate the hydrocarbons from one another is 
fraAional distillation, we have applied ourselves to the 
task of measuring the vapour-tension of the individual 
hydrocarbons at different temperatures. 

Every chemist knows that the every day operation o^ 
taking the boiling point of a liquid is in point of fad a 
special vapour-tension observation, and that the boiling 
point is another name for that point of temperature at 
which the tension of the vapour of the liquid is equal to 
760 m.m. of mercury, the average pressure of the atmo- 
sphere. Instead, therefore, of using a distillatory 
apparatus and observing the temperature registered by 
the thermometer immersed in the vapour of the liquid 
during distillation, we might arrive at the same result 
by the employment of the apparatus for measuring the 
tension of the vapours evolved by liquids at different 
temperatures. 

The apparatus which we employ we have ourselves 
construded, and one of its peculiar advantages is that by 
its aid we are able to ascertain the boiling point of a very 
minute quantity of liquid. A single decigramme of a 
specimen of liquid is amply sufficient for such determina- 
tions. 

Our work in this diredion is only just at the com- 
mencement, and this map of vapour tensions is a pre- 
liminary chart (a chart accompanies the paper), exhibit- 



ing part of the curve of tension of eleven consecutive 
terms of the kerose series. 

The Tmsio-meUr (as we name our new instrument) 
has a future rich in promises. In carrying out the 
fradionation of a mixture of liquids boiling very near 
together, it provides a criterion indicative of the com- 
pletion of the fradionating process. When the distilla- 
tion has been pushed to complete dryness there will 
always be a few drops of residual liquid on allowing the 
retort to cool. When the tension of those few drops 
approximates to the tension of the original liquid — that 
is a sign that the fradionation has reached completeness, 
and the Tensio-meter enables that comparison to be 
made. 

Light on the question whether, in a given instance, 
there is specific adhesion between the constituents of a 
mixture may be looked for by having recourse to this 
instrument, which imparts a degree of certainty and 
completeness to the fundamental operation of fradional 
distillation which has hitherto been altogether wanting. 

In conclusion I exhibit four terms of the marsh gas 
series, viz.: — 

Marsh xi. formula CnHij 
Marsh xv. „ C15HX7 

Marsh xvi. „ CxgHis 

Marsh xvii. „ Cx7Hiq 

In presence of these substances chemists will be com- 
pelled to revert to that atomic weight of carbon which 
was all but universally admitted forty years ago. 

Laboratory, New Maiden, Sorrey. 



ON THE FORMATION CM? CITRIC ACID BY 

THE OXIDATION OF CANE-SUGAR, 

By EDWIN F. HICKS. 

Some time ago Dr. Phipson, in the Chbmical Nbws 
(vol. Ixxi., p. 296) announced that he had obtained an 
acid which he regarded as citric acid, as a result of the 
oxidation in the cold of an acidulated (HaS04) solution of 
cane-sugar with permanganic acid. After the solution 
became clear, it was carefully neutralised with ammonia, 
calcium chloride solution was added, and the solution on 
boiling gave the precipitate which was described as con- 
taining citric acid. 

Soon after this announcement, Messrs. Searle and 
Tankard repeated Dr. Phipson's work with great care 
(Chemical News, Ixxii., 31), and although they obtained 
a precipitate on neutralising, adding calcium chloride and 
boiling, it did not in any way resemble calcium citrate. 
On the contrary, this precipitate was proved, by analysis 
and microscopical examination, to consist in every case 
of hydrated calcium sulphate, CaS04.aH20. Further, 
when nitric acid was used for the acidulation in place of 
sulphuric, no precipitate was obtained on treating and 
boiling the solution as before. 

Previously to the work of Searle and Tankard I had 
done some few experiments according to the direAions 
given in Phipson's note. Owing to lack of time my 
results obtained then were not eoodusive as to the nature 
of the precipitate, except that I could not confirm it at 
being calcium citrate according to any of the ordinary 
tests for citric acid. 

Recently, having more time at my disposal, I again 
undertook to repeat the experiments, following out the 
diredions given by Dr. Phipson as exadly as possibloi 
but varying the conditions in order to note any difference 
in the course of the readion with different relative 
amounts of acid and permanganate, as well as the con- 
centration of the solution. My results in every way 
corroborate those anticipated by me in the work of Searle 
and Tankard. 

The results of my experiments may be briefly sum- 



166 



Determination oj Boric Acid. 



I CatHtCAt News, 
1 oa. 4f 1895. 



marised. When the solution contains a greater quantity 
of H^04 than z to zoo, precipitation takes place on 
standing in the cold ; and for eqnal concentration and 
permanganate added, is greater the more acid present. 
On filtering and boiling further precipitation takes place. 

When the amount of acid present is less than z to zoo, 
no precipitation takes place in the cold, but on boiling a 
finely crystalline white precipitate is formed, its relative 
amount bearing the same relation to the amount of acid 
present as in the first case. On adding alcohol to the 
filtrates from these precipitates a further precipitate is 
thrown down. All the precipitates obtained were 
thoroughly washed with boiling water. 

One description will suffice for all, whether obtained by 
precipitation in the cold, after boiling, or on treating the 
filtrates with alcohol. In every case they consisted 
entirely of pure hydrated calcium sulphate, CaS04.2HaO. 
No trace of any organic acid was found. All the pre- 
cipitates were finely crystallised and easily identified with 
the microscope, which was supplemented by obtaining 
the confirmative chemical tests. 

I also used a nitric acid solution and obtained results 
identical with those described by Searle and Tankard 
{he. eit.). 

In conclusion, it would seem that this work, although 
iBXftly a repetition, is not altogether out of place, as Dr. 
Phipson in a second note (Chbmical Nbws, vol. Ixxii., 
zoo), not having repeated his experiments, seems to 
doubt the conclusions, and has pointed out certain possible 
errors of conditions in the work of the two chemists 
mentioned above. 

I think my work has completely covered these con- 
ditions, and can leave no doubt as to the composition of 
the precipitate, and has further shown that it is obviously 
futile to look for the formation of citric acid, unless other 
conditions than those specified are admitted. 

$tt Beaver Street, New York City. 
September 16, 1895. 



ON THB 

VOLUMETRIC DETERMINATION OF METALS. 
By M. LBSCCEUR. 

L. Barthb has recently given a process for determining 
the free acid and the metal in a salt of zinc containing 
acid in excess. To this end he uses a normal alkali and 
two indicators, phenolphthalein and the colouring matter 
of the red hollyhock. He ascribes to the precipitate 
formed by the alkaline solution in the salt of xinc at the 
moment when the phenolphthalein turns of a rose colour 
the composition of a basic salt, (ZnO)4S04Zn. Hence it 
is necessary to multiply the number of c.c. of the normal 
solution of potassa by f in order to calculate the metal in 
the manner usual in volumetry. 

For several years I have employed for the volumetric 
determination of metals in salts in presence of an excess 
of acid a method almost identical with that of Barthe. As 
an indicator I use simultaneously methyl-orange (Orange 
No. 1 1 1, of Poirrier) and phenolphthalein. The former indi- 
cating by its gooseberry tint the presence of a free acid, 
and looming decolourised by the addition of alkali at the 
exaA moment when neutrality is reached; the second in- 
dicating the moment when free potassa exists in the 
mixture, and showing by its change the end of the pre- 
cipitation. As for sine, I have not observed the forma- 
tion of a sub-salt. Analysis shows that the produd col- 
leAed at the moment of the change of colour of the 
phenolphthalein, after washing and desiccation, is xinc 
oxide. Perhaps the washings efieAed after precipitation 
have destroyed the basic salt ? 

The following experiment shows that this is not the 
case, and destroys the hypothesis of Barthe :— 

One grm. of commercial zinc sulphate, titrated with 



normal soda (caustic), required 6 c.c. of the solution to 
turn the colour of the phenolphthalein (a result corre- 
sponding only to o*86z grm. of ZnS04.7HaO). The pre- 
cipitate is coUeAed upon a filter, washed with boiling 
water, and re-dissolved in hydrochloric acid. But on the 
one hand, the washings do not contain Mine, and on the 
other hand, thi hydrochloric solution docs not contain sul^ 
phuric acid. 

The precipitate is therefore xinc oxide free from sul- 
phate. The method is only rendered more simple, no 
corredion beine necessary, and the normal solutions of 
soda and xinc being volumetrically equivalent.— B«/l« d$ 
la Soc, Chim, de Paris, 



ON THE DETERMINATION OF BORIC ACID. 
By H. JAY and M . DUPASQUIER. 

Amonq all the procedures for determining boric acid, that 
with methylic acid is the most trustworthy, as it enables 
us to isolate with accuracy the total produd to be deter- 
mined. The modification which we have introduced into 
this method, which consists in the manner of distillation, 
and the peculiarity of the titration, enables us to apply it 
in all cases, which was not pradicable with the opera- 
tion as hitherto described. 

The substance in question, dried and pulverised, after 
being freed from any organic matter, is acidulated with 
hydrochloric or sulphuric acid in very small excess, intro- 
duced, along with 2$ to 30 c.c. of methylic alcohol, into a 
flask fitted with a cork having two perforations. One of 
these orifices admits a perpendicular tube bent at its 
lower end, descending almost to the bottom of the flask 
and traversing a refrigeratory at its upper part. The 
other orifice admits a delivery-tube leading into a second 
flask, like the former, and plunging to the bottom. A 
second delivery-tube, sealed to the perpendicular tube, 
enters the second flask, which before the commencement 
of the operation receives z, a, or 3 c.c. of a normal solu- 
tion of potassa or soda (freed from carbonic acid), accord- 
ing to the supposed quantity of boric acid, and having 
always an excess of alkali. 

The two flasks, when conneAed, are heated separately io 
the water- bath. The methylic alcohol conveys the boric 
acid from the first flask to the second, in which it is re- 
tained by the alkalis, finding its way into the refrigerator 
to re-descend again, effeaing in a continuous manner the 
complete extradion even of large proportions of the boric 
acid. The time consumed by the operation is variable, 
but for 300 m.grms. it does not exceed ninety minutes. 

After having experimented with various indicators, we 
prefer litmus paper and the blue C. L. B., the latter 
already indicated by Engel. 

The alkaline liquid containing the boric acid is gently 
heated so as to expel the methylic alcohol and to be con- 
centrated to a constant volume; it is then rendered 
slightly acid by means of a few drops of dilute hydro- 
chloric acid, warmed afresh to volatilise any traces of 
carbonic acid which have been introduced during the dis- 
tillation. We cool to Z5~20^ and titrate with a deci- 
normal solution of potassa or soda free from carbonic 
acid until a small drop placed upon litmus paper is found 
neutral. Then follows the titration of the boric acid. We 
add to the liquid two drops of an aqueous solution of blue 
C.L.B., at zo grms. per litre, and pour anew the titrated 
liquid until the first change of tint. The quantity of 
liquid employed, after dedu&ng o*a c.c. or 0*3 cc, ac- 
cording to volume, indicates exadly the proportion of 
boric acid present. 

The conditions necessary for obtaining exad results are 
uniform volumes and constant temperatures, as also the 
elimination of the carbonic acid and of methylic alcohol. 

In a series of experiments on wines to which known 
quantities of boric acid had been added along with, in 
some cases, hydrochloric acid and fluorine compounds, 



C«IMlC4t NBWt^f 

Oa. 4* ■895- I 



Report of Committee on Atomic Weights. 



167 



the aathors found that hydrofluoric acid alone effeaed a 
slight excess of the proportion introduced, and falsified 
the results to that extent. But they believe that this 
slight excess may be negle^ed in pradice. The process 
has been further verified upon wines of different growths, 
apon ciders, perries, and wines. — Comptes Rendus^ cxxi., 
p. 260. 

REPORT OF COMMITTEE ON ATOMIC 

WEIGHTS, PUBLISHED DURING 1894.* 

By P. W. CLARKE. 

(Continaed from p. 137)* 

Palladium. 
In Z889 Keiser published his determinations of the atomic 
weight of palladium, for which, since then, other investi- 
gators have found somewhat different values. He has 
now, jointly with May B. Breed, given a new set of deter- 
minations, which confirm his former series (i4m.CAtfffi.y., 
xvi., 20). As before, palladi ammonium chloride was re- 
duced in hydrogen, the salt being prepared by two 
methods and carefully examined as to purity. Two series 
of experiments are given, with the following weights of 
material :« 

First Striis, 
Pd(lf H.CI),. Pd. Al. wt. Pd. 

1*60842 0-80997 106-271 

208295 1*04920 X06-325 

2-02440 1*01975 106 334 

2*54810 1-28360 106-342 

^•75505 0-88410 106*341 





From sum of weights • • Z06-325 
Reduced to vacuum • • X06-246 






Sicond Sifiis. 




i-5oa75 
1-23672 

I-34470 

1-49059 




067739 
075095 


106*297 
X06-296 
J06-343 
106*353 




From sum of weights • • 106-322 
Reduced to vacuum • • 106-245 



The atomic weight was computed with H ■■ i, N « 14*01, 
and Cla35*37. If O* 16 this becomes Pda 106*51. This 
U onljr 0-02 lets than the value obtained in the earlier 
investigation. 

TUNOSTBN. 

A new determination of the atomic weight of tungsten, 
by Pennington and Smith (read before the American 
Philosophical Society, Nov. 2, 1894), leads to a much 
higher value than that commonly accepted. The older 
work seems very probably to have been done upon material 
cootaminated with molybdenum, an impurity which was 
eliminated in this investigation by Debray's method,-— 
that is, by volatilisation bv means of gaseous hydrochloric 
acid. The metal, carefully purified, was oxidised in 
porcelain crucibles, with all necessary precautions, and 
the following data are given : — 

Wt. W. Wi. o,. At. wt. W. 

0*862871 0*223952 184-942 

0-650700 0-Z68900 184*923 

0*557^54 0-155 143 184909 

0*060820 0-173 103 184-902 

0*428228 o* z I X 1 68 184*900 

0*671920 0*174406 184*925 

0*590220 0153x93 184*933 

0*568654 0x47588 184*943 

1-080973 0*280600 184-913 

Mean • . 184-921 

* From the Journal of the American Chemical Society, vol. ivii.. 
No. 3. Read at ths Box too IfectioK. Dec. 28, 1894. 



All weights are reduced to a vacuum, and Oai6 is 
taken as the standard of reference. 

Another paper, by Smith and Desi, was read at the 
same meeting with that just cited. In this research, the 
tungstic oxide was purified in the same way, and reduced 
by heating in a stream of pure hydrogen. The water 
formed was weighed, and all weights reduced to a vacuum. 
Computed with Oaz6and H« 1*008, the results are as 
follows : — 

Atwt. W. 

X84-683 

184-709 

X84-749 

184*678 

184704 
Z84-706 

Mean • • 184-704 

Why this result should be lower than that previously 
found by Pennington and Smith remains to be explained 
(To be continued). 



Wt. wo,. 


Wt. H,0. 


0-983024 


0-22834 


0-998424 


0-23x89 


1*008074 


0-23409 


0-911974 


0*21 184 


0*997974 


0-23x79 


1-007024 


023389 



ON THE VAPOUR-TENSIONS OF MIXTURES 

OF VOLATILE LIQUIDS/ 

By C. E. LINBBARGBR. 

Introductory, 
The investigation of the elastic forces or tensions of 
vapours emitted by a solution of a fixed substance in a 
volatile liquid has received much attention, especially 
within recent years. The impetus for investigations of 
this kind is, in a great measure, due to the new notions 
that have been introduced into science in regard to the 
nature of solutions. The possibility of ascertaining the 
molecular mass of a substance from a determination of 
the amount of the depression of the vapour*tension of a 
liquid, occasioned bv its being dissolved therein in knowa 
proportions, has induced chemists to study carefully this 
field of scientific inquiry, which it may truly be said bat 
been gone over very elaborately. 

In the greater part of the work that has been done, 
both theoretical and experimental, it has been assumed 
that the dissolved substance is not appreciably present in 
the gaseous state, and but sparingly present in the liquid 
state ; in other words, the dissolved substance is supposed 
to be involatile, and the solutions are made dilute. 

Now, absolute involatility in any body whatsoever 
cannot be afiSrmed ; there must always be, at every tern* 
perature, some degree of power of assuming the gaseous 
state, although it mav be so slight as to be imperceptible 
to our senses. Still, for all pradical purposes, the 
assumption of non-volatility in many substances can be 
admitted, as our means of experimentation are not 
sufficiently delicate to deteA any small amount of 
volatility. 

Although so much has been done on the vapour-tensions 
of solutions of fixed substances in volatile liquids, com- 
paratively little attention has been paid to the study of 
the vapour-tentions of mixtures of the volatile liquids ; 
yet this is the general case, of which the restriaion that 
the dissolved substance be fixed makes only a special 
application. It must, indeed, be allowed that the con- 
sideration of a mixture of vapours, instead of a single one, 
introduces certain complications into the problem ; and 
this is, perhaps, just the reason so little work has been 
done on this part of the subjea ; still difficulties of this 
sort are probably not uniurmountable. 

The limitations of work on vapour-tensions to dilute or, 
at most, moderately concentrated solutions cannot bo 

• Abridmd from the Joufmal of tk$ Amritun Chimicai Soctety. 
vol. XTii., No. 8, Angnst, 189s. 



i68 



Vapour-tensions of Mixtures of Volatile Liquids. 



{ Chimicai. Niws, 
1 Oa. 4. X895. 



said to be satisfadory. True, the theory of solutions has 
been developed on the hypotheses that dtssolyed matter, 
in analogy with gaseous matter, is in a state of con- 
iiderable dilution; and experimental confirmations of 
theoretical predidions can be expeded only when such a 
state of affairs is realised. Nothwithstanding that cir- 
cumstance, it seems of importance to extend our line of 
operations and attack the problems presented by con- 
centrated solutions ; perhaps they will be found to exhibit 
fewer anomalies than has been supposed. 

There are two circumstances which render work that 
has hitherto been done on the vapour tensions of mixtures 
of volatile liquids of all concentrations unsatisfadory ; 
they are to be found in the choice of the liquids investi- 
gated, and the kinds of vapour- tension measured. The 
liquids chosen were almost invariably those which are 
now recognised to be made up of associated molecules ; 
thev are just those which exhibit the greatest abnor- 
malities in resped to most of their properties, and it 
cannot be cxpeAed that simple relations, if they exist at 
all, will be discovered when such liquids are used as 
material of investigation. All investigators also, almost 
without exception, have measured only the total pressure 
of the mixtures of liquids examined, which is the sum of 
the partial pressures, these, however, being entirely 
unknown. But more important is it to know the share 
which each vapour has in the exerting of the total 
pressure, and only when this is learned can our knowledge 
of the matter be said to be in any adequate measure 
complete. 

This paper seeks to fill in some degree this gap in the 
tubjed^ of vapour-tensions. The method employed is 
such as to permit of the specification of the partial 
pressures of a mixture's components, and also of their 
concentrations in the gaseous phase. The choice of the 
liquids has been made with an eye towards employing 
those which have been found to be most ** normal,'* so 
that in the examination of more complex liquids, that is, 
those consisting of associated molecules, the simplicity 
to be expeded in the phenomena of the former may aid 
us in getting some light on the possible intricacies of the 
latter. All the mixtures examined are freely soluble in 
one another, so that no disturbing influence from layer- 
formation can take place. 

In reality, we have before us a case of equilibrium ; the 
equilibrating system consists of two substances, each 
present in two phases, the liquid and gaseous. We have 
to ascertain at the points of equilibrium the temperature, 
the partial pressures of the two substances in gaseous 
phase, and their concentration in both liquid and gaseous 
phase. 

Description of Apparatus, 

It is of prime importance in the determination of vapour- 
tensions that the temperature be kept uniform ; accord- 
ingly I describe, first of all, the apparatus employed for 
that purpose. 

Thtrmostat, ^Thit consisted of a cylindrical copper 
vessel holding nearly forty litres of water. It was heated 
by means of a ring burner ; the pressure of the gas was 
kept constant by means of a pressure-regulator, and a 
thermo-regulator as described by Ostwald {Ztschr, Phys, 
Ckim,, ii., 565, x888), controlled by combustion of the 
gas. To insure uniformity of temperature in all parts of 
the bath, the water was kept in constant agitation by 
means of a number of fine streams of air blown np through 
it, the laboratory being provided with air under pressure. 
Such a means of agitation gives very satisfadory results ; 
it takes up but very little room, and permits of the exami- 
nation of the pieces of apparatus plunged in the water by 
shutting off for a few seconds the flow of the air. 

The temperature of the bath remained constant to 
within 005° during an experiment; the thermometer 
employed was one graduated to tenths of degrees, and 
had recently been tested by the '* Physikalische Reichsan- 
stalt'* of Berlin. 



The apparatus consisted of three principal parts, each 
made up from material easily found in almost every 
chemical laboratory. The first part consists of those 
pieces required to measure a dennite volume of air, to 
compress it enough to force it through the apparatus, and 
to dry it thoroughly ; the second part is the contrivance 
for saturating the volume of air with the vapour of the 
liquid under examination ; and the third is the arrange- 
ment for the analysis of the gaseous mixture. 

First Principal Part of Apparatus, — This consists of a 
measuring vessel, a vessel for regulating the internal 
pressure, a manometer, and a system of drying tubes. I 
pass to the description of each. 

The Measuring Vessel consists of an ordinary bottle of 
a capacity varying from one to three litres, according as 
it is required to employ a larger or a smaller volume of 
air ; the height of the bottle should be such that only the 
neck is above the water; in its neck is fitted a good 
rubber stopper through which passes one branch of a 
T tube. This branch of the T tuoe is made of tubing of 
about a quarter inch bore, and is about eight inches long, 
while the other branch has only half this bore, with a 
length of about 3 inches. The wider branch of the tube is 
pushed through the stopper so that its lower edge is just 
flush with that of the rubber, and care is taken that this 
adjustment is in every experiment maintained, as well as 
that the stopper is always inserted to the same distance 
in the neck of the measuring vessel. In the upper end of 
the wider branch of the T tube is inserted (an air-tight 
joint being assured by the use of rubber tubing) a tube 
somewhat drawn out and narrowed at its lower end, and 
provided with a stop-cock at its upper end. The end of 
the lower part must be about a half inch above level of 
the stop of the measuring vessel, and the upper end is 
put, by means of a piece of rubber tubing, in communica- 
tion with a water supply at constant level about a yard 
above the thermostat. If the stop-cock be opened water 
will flow into the vessel, and displace the air therein con- 
tained which escapes through the side branch, which, 
being in the middle of the vertical branch, is an inch or 
so above the orifice of the tube introducing the water. 

Sufficient mercury is poured into the vessel to make it 
sit firmly on the floor of the thermostat. The residual 
volume of the vessel is carefully determined by pouring 
into it from graduated vessels, enough water to fill it up 
to the level with the upper surface of the stopper. If the 
adjustment of the stopper and the tubes be always the 
same, duplicate determinations of the capacity do not 
differ by more than one-half c.c If the same volume of 
mercury always be taken, the volume of water will repre- 
sent the volume of air passed through a liquid or mixture 
of li(^uids undergoing investigation in all determinations. 

It IS superfluous to make corredions for the expansion 
of the mercury and the glass when determinations of 
vapour-tensions are made at higher temperatures, as the 
error of the estimation of the capacity exceeds the 
amount of the corredions. 

The Pressure Regulator consists of a bottle of any con- 
venient size, provided with enough mercury to make it 
stand steadily under water, and fitted with a twice per- 
forated rubber stopper. Through one of the holes of the 
stopper passes a tube nearly to the level of the mercury 
and furnished with a stopcock at its upper end; this 
tube is conneded by means of rubber tubing with the same 
water source as the measuring vessel. In the other hole 
is fitted a T-tube, of which one of the horizontal branches 
is conneded by means of a bit of stout rubber with the 
narrower branch of the T*tube belonging to the measuring 
vessel, while the other is attached by rubber tubing to 
the other parts of the apparatus. If water be run into 
the bottle serving as pressure regulator, the air in it is 
compressed until it can force itself through the liquid 
with the vapour of which it is to be saturated. 

The Manometer is intended to measure the amount of 
this compression or the internal pressure ; it is made of 
ordinary glass tubing bent into (j-shape, with the branches 



CatmcAL Ntwi, I 

oa. 4. X895. r 



Vapour-tensions of Mixtures of Volatile Liquids. 



169 



about two feet long. It may be put between the meas- 
uring vessel and the pressure regulator, or between the 
drying tubes and the latter ; I have found it most con- 
venient, however, to melt it into the vertical branch of 
the T-tube of the measuring vessel just opposite the 
horisontal branch, as shown in Fig. i. The manometric 
liquid is water, and the differences of the heights of the 
liquid columns of the two branches, is read to a milli- 
metre by means of a metric rule ; the readings are then 
easily exaA to a tenth m.m. of mercury. 

Th4 Drying Tubtsctm, of course, be of various shapes 
and filled with various drying agents. Liquids, such as 
strong sulphuric acid, must be rejeded, however, as they 
increase the Internal pressure, and often cause an irregu- 
larity in the flow of the gas. I found tl-^ubes to be the 
best shape, and grains of pumice stone, soaked in con- 
centrated sulphuric acid, the best drying ag^nt ; a length 
of at least 60 cm. is to be taken, and the pumice must 




= jj»-* AMf af, M^jml^tk 



Fig. I. 



be changed often. When it becomes necessary, in work 
on acid solutions, to remove the carbon dioxide from the 
air, an additional tube filled with soda-lime is taken. At 
the end of the last U tube, a mercury valve is attached to 
prevent the backward diffusion of the vapours ; this is of 
the smallest siae convenient, and the delivery-tube dipping 
into the mercury of capillary dimensions. 

Sicond Principal Part of ApfaratMs,^Th'\% is the 
absorption vessel, which may consist of a simple potash 
bulb according to Mohr. I found it better, however, to 
add two more bulbs, making five small and two large 
ones. As liquids which dissolve rubber somewhat were 
often introduced into the apparatus, and as it was neces- 
sary to let it stand some time before weighing, the outlet 
and inlet tubes were provided with tiny ground glass 
stoppers. At first the bulbs were shut up in a copper 
case set in the thermostat ; the case had holes in its sides, 
below the surface of the water, for the condnaion and 



abduAion of air, platinum capillaries and ground glass 
caps being employed to make the connedioos. This 
arrangement was not, however, found satisfa^ory, since 
one was never sure, air being such a bad condudor of 
heat, that the contents of the bulbs had the same tern* 
perature as that of the bath. Also, the platinum tubes 
proved to be very delicate, breaking readily if bent often, 
which was inevitable. It was accordingly found best to 
plunge the absorption vessel diredly into the water of 
the bath, connexion with the system of drying tubes 
being made with a bit of stout rubber tubing of small 
bore. When the vessel was removed from the water it 
was carefully wiped dry and set in the balance case, the 
atmosphere of which was kept dry by means of con- 
centrated sulphuric acid. 

Third Principal Part 0/ Apparatus, ^In order to analyse 
the mixture of vapour issuing from the absorption vessel 
two modifications of this part of the apparatus are 
required— one to be employed when the gaseous mixture 
contains a halogen compound of carbon, and the other 
when it contains an acid. In the first, the compound was 
decomposed by heated lime, and, in the second, the acid 
was absorbed by a solution of potash or baryta. In the 
following lines a description of each is given. 

X. The outlet tube of the absorption apparatus is fitted 
by means of a good cork into one branch of a (J-^^^ of 
rather thick glass; this branch is bent at right angles at 
about the middle of its length, while the other branch is 
left straight. The latter branch is held clamped to a 
heavy, and hence steady, retort-stand set beside the 
thermostat, and is conne^ed by means of a narrow lead 
tube to a tube of hard glass placed in the gutter of a 
combustion furnace. In the further end of the hard 
glass tube, a Maquenne absorption apparatus, containing 
a little dilute nitric acid, is inserted, the connexion being 
made with a rubber stopper ; this outlet of the absorption 
apparatus is in communication with a suAion pump, and 
in the rubber tube making this conneAion a T-tQl>c ** 
interposed, over the open end of which is slipped a piece 
of rubber tubing long enough to reach to the thermostat. 
When this tube is open, the interior of the apparatus, up 
to the liquid in the absorption vessel, is under atmo- 
spheric pressure ; if it be pinched together a little so as 
to prevent enough air to feed the sudion pump from 
entering, the pressure in the apparatus may be made lesa 
than that of the atmosphere; by this little device it is 
possible to regulate the pressure with great nicety. 

2. This analjrsing apparatus consists simply ol a potash 
bulb, according to Liebig, made ol thick glass; one 
branch is flared out to receive the outlet tube of the 
absorption vessel, and the other is straight so at to glide 
up and down in a clamp of a retort-stand. 

The pieces of apparatus just mentioned will receive 
complementary description in the diredions for perform- 
ing experiments. 

Perjormanci of an Experiment when the Mixture con- 
tains an Organic Halogen or Sulphur Compound. — ^The 
hard glass tube (about 80 cm. long) is filled with lime or 
sodium carbonate just as in a determination of halogens 
in organic analysis, joined to the lead tubing which 
establishes communication with the U*^ubes held in a . 
clamp just above the surface of the water in the thermo- 
stat, and placed in the furnace. The gas is now lighted 
and the tube with its contents heated up to a red heat, 
while a current of dried air is passed through it to remove 
all moisture. 

The measuring vessel, the pressure regulator, and the 
system of drying tubes are joined air-tight together, and 
so set in the thermostat that as much room as possible 
is left for the absorption vessel. 

The absorption vessel is filled with the liquid or solu- 
tion under examination, a few bubbles of air drawn 
through so as to get the liquid beforehand in the right 
position, and carefully weighed. It is then conne^ed 
with the U-tube (of course, no air is now being passed 
through the analysing tube}, and after a couple of 



170 



The late Louis Pasteur. 



i CRBM ICAL, NbWS, 
\ Oa.4,i89S* 



minutei of half-Bubmertion in the bath, it is attached to 
the system of drying-tubes. It is now wholly submerged 
in the bath and air is made to pass through it as fol- 
lows :— 

The stopcock of the pressure- bottle is opened so that 
water majf be run in slowly and, by compression of the 
air, gradually increase the internal pressure. As soon as 
bubbieB of air commence to pass out of the absorption 
vessel, the stopcock of the pressure-regulator is closed, 
and that of the measuring vessel opened. The water 
issues in drops or a fine stream in full sight of the 
operator, and its rapidity of flow can be very easily regu- 
lated. Experience has taught me that about a litre an 
hour was aoout the best rate ; after a brief acquaintance 
with the apparatus, it is possible to judge very closely 
from the rate of the flow how long it will take for the 
measuring vessel to become filled. While the operation 
is proceeding, the height of the manometric column is 
read off at several different times ; if the rate of flow is 
constant this does not vary by more than i or 2 m.m. 
of water, or less than one-tenth m.m. of mercury. 

The barometer is also read off at the beginning and at 
the end of the experiment ; in all my determinations, the 
difference of the two readings was less than one m.m. of 
mercury. 

A minute or so before the measuring vessel is full, the 
absorption*bnlbs are lifted out of the water enough to bring 
the end-tubes about 2 inches above the surface, and there, 
together with the joining tube on one side and the cork 
and end of U*tube on the other, are carefully dried with 
filter-paper. When the water in the measuring flask has 
reached the mark on the T-tube (level of cork), the absorp- 
tion vessel is detached from the drying-tubes, and the 
little glass stopper fitted into its inlet tube. Immediately 
after this operation the connexion between the absort)tion 
vessel and the lj*tube is broken, and as soon as this is 
done a perforated cork, through which passes a narrow 
glass tube so bent at right angles that a long vertical 
branch is obtained, is fitted into the U-tube, its objed 
being to prevent the escape by diffusion of any portion of 
vapour contained in the (l-tube. A current of air is now 
drawn through the tubes, slow at first to avoid causing 
too much vapour to pass over upon the heated lime all 
at once, as, if there be a deficit of air, the combustion is 
incomplete, and free carbon colleds in the cooler portion 
of the tubes ; in a well-conduded experiment, the lime 
should remain perfeAIy white. Towards the end of the 
determination, a more rapid stream of air is drawn through 
the apparatus, so that one may be sure that all the halo- 
gen compound has been brought into contad in the de- 
composing agent. If any free carbon collets in the tube, 
or if the dilute nitric acid in the Maquenne absorption- 
bulb shows on the addition of silver nitrate the slightest 
trace of cloudiness, the determination ought to be rejeAed 
as untrustworthy. 

The absorption vessel, as soon as possible after its re- 
moval from the water in the thermostat, should be closed 
with the second tiny stopper, wiped dry, and set in the 
balance case, where it takes on the temperature of the 
room. When this is thought to have taken place, it is 
weighed, and the loss of weight set down as the eva- 
porated quantity of solution. When the furnace has 
cooled down the lime tube is removed, and its contents 
washed out with water and nitric acid into a flask, which 
is set over a flame and boiled until complete solution 
ensues, more nitric acid being added if necessary. If 
more than a half grm. of the halogen compound has eva- 
porated, the solution is brought to a certain volume and 
an aliquot portion of it taken for analysis. 

Most of the analyses were made by the gravimetric 
method of determination of halogens by precipiution 
with silver nitrate; some, also, were analysed volume- 
trically, Volhard's method being employed. 

Pifformanci of an Bxfttiwunt wkin iki Mixture con- 
taini an Acid.^ht absorption vessel is filled with the 
mixlara being investigated, and weighed as described 



above. It is then joined by means of a good cork to the 
analysing apparatus, into which are run from a pipette 
10 c.c. of a stock solution of potash or baryta ; the 
pipette being provided with a straight calcium chloride 
tube filled with soda-lime, all contamination from the 
carbonic acid of the breath is avoided. The alkaline 
liquor is of such strength that it is more than sufficient 
to neutralise the vapourised acid. The further end of the 
analysing arrangement is closed with a U-tube filled with 
soda-lime, so that the alkaline solution may be in contaA 
with an atmosphere free from carbon dioxide. 

The two pieces of apparatus thus filled and joined to- 
gether are submerged in the water of the thermostat, the 
whole being held in place with a clamp embracing the 
upright tube of the analysing contrivance and attached 
to a heavy retort stand. The other end of the absorption 
vessel is then placed in communication with the drying 
tubes, &c., by means of a short bit of stout rubber tubing. 

The internal pressure is regulated and the air passed 
just as described in the preceding sedion, note being 
taken of the amount of internal pressure, the volume of 
the air, and the barometric height. A slight corredion 
has to be made to the barometric reading for the following 
reason :— After the air passes the liquidcontained in the 
absorption vessel, and comes into the analysing tube, it is 
under a pressure equal to that of the atmosphere plus 
that due to the weight of a column of liquid corresponding 
to the difference of level between the two surfaces of the 
alkaline solution ; this, in my apparatus, was determined 
to be equal to i m.m. of mercury, which was added to all 
barometric readings. 

When the measured volume of air has passed through 
the apparatus, the stopcock, through which water enters 
into the measuring vessel, is closed, the absorption and 
analysing vessels are lifted nearly out of water, and after 
the joint between the absorption vessel and the system of 
drying tubes has been wiped dry, it is broken. Both the 
pieces of apparatus are wiped dry with bibulous paper, 
and agitated somewhat so that any acid vapours m the 
bulbs may be brought in contad with and absorbed by 
the alkaline liquor. 

The pieces are then disconneAed, the absorption vessel 
stoppered and set in the balance-case, while the contents 
of the analysing vessel are poured into a beaker, rinsing 
being done with water free from carbon dioxide. Without 
delay, the excess of alkali is estimated by titration 
against decinormal acid solution, and by a simple calcu- 
lation the quantity of evaporated acid is obtained. 
(TobecoDtinoed). 



OBITUARY. 



THE LATE LOUIS PASTEUR. 

On September 29th Science, and especially the science of 
France, underwent a severe loss in the person of Louis 
Pasteur, one of the most successful students of that world 
of wonders, *' the infinitely little.*' In our brief notice of 
the illustrious deceased we must first point out that he 
was not a medical praditioner, not even in the strid sense 
of the word a biologist. He was essentially a chemist — 
of course, in the French and German acceptation of the 
term. His earliest scientific studies and his first dis* 
coveries were on chemical questions. His scientific 
education was developed at the Ecole Normale, an insti- 
tution which permits and even encourages individual 
effort He observed for the first time the charaderistic 
difference between tartaric and paratartaric acid, the crys- 
tals of the former having no plane of symmetry in common 
with those of the latter. He separated the double sodium 
and ammonium paratartrate into two salts having an in- 
verse aaion on the plane of polarisation of light. The 
welcome which this capital discovery received from Biot 



ChbmicalKiws»\ 
Oa. 4f 1895. I 



Genesis of the Elements. 



171 



and other leading AcademicianB won for Paateur the 
position of Assiatamt Professor of Chemistry at the Uni- 
versity of Strashurg. His researches now led him to the 
coodnsion that ail the produds of inorganic nature are 
not dissymmetrical, while vegetable and animal prodads 
are atomically dissymmetrical. In this charaderistic he 
hoped to find the key to the problem of animating inor- 
ganic matter. He discovered a connedion between the 
researches of chemistry and crystallographic physics, and 
the dawning results of physiological chemistiy. His at- 
tention was now turned to the study of fermentation. He 
was nominated Dean of the Faculty of Sciences at Lille. 
As the distrid is largely interested in the manufadure of 
alcohol, he resolved to devote a course of ledures to the 
study of fermentation. He soon recognised the influence 
of the presence of a living organism. This view involved 
him in a controversy with Liebig, which ultimately ter- 
minated in the recognition of the new theory which was 
found applicable in the manufadure of vinegar. Liebig, 
it must be added, declined Pasteur's challenge to submit 
the question to an experimental investigation before an 
Academic Commission. 

Next arose the question of spontaneous generation. 
Redi, Spallanzani, and Swammerdam denied the possi- 
bility of this alleged process. Aristotle, Buffbn, and 
Pouchet affirmed it. It became the duty of Pasteur to 
take a decisive part in the contest. He had just been 
entrusted with the scientific studies at the Ecole Normale. 
But he had no laboratory, and had to furnish one at his 
own expense in a garret at the Ecole Normale 1 At last 
Pouchet and Jolv, his opponents, withdrew from the con- 
test. It must be remembered that the cause of spon- 
taneous generation — heterogeny—sufiered severely from 
the experiments of Tyndall. 

The importance of Patsteor's researches has since been 
extending. They have thrown a new light on the manu- 
fadure of wine and beer, and on the propagation of 
disease, both in man and in the lower animals. At the 
present time we are on the point of recognising in a 
development of Pasteur's researches, a means of confer- 
ring on man immunity against malaria and against the 
bites of the most deadly serpents. 

Surely we may pronounce the life-work of Louis 
Pasteur glorious, alike from the point of view of pure 
science, and that of pradical utility ; glorious to himself 
and to his country. 



NOTICES OF BOOKS. 



Die QiMsis dit BUmente von William Crookes. Bin 
Voftrag gehalUn in dit *' Royal InBtitution " mu London, 
am i^in Fibruar, 1887. ('* The Genesis of the Ele- 
ments, by William Crookes : a Discourse delivered at 
the Royal Institution of London, on February z8th^ 
1887.") Brunswick : Friedrich Vieweg and Son. 2895, 
Wb have before us the second edition of the German 
version of Mr. Crookes*s Discourse on the " Genesis of 
the Elements.'' 

The translation is from the pen of Prof. Dr. W. Preyer, 
who is not merely a thorough English scholar, but whose 
researches have been to a considerable extent devoted to 
kindred subjeds. Hence he has been able and willing to 
present to the German scientific public the views of Mr. 
Crookes not only accuraUly but fairly. 

This double qualification is no mere tautology. Just 
as an orator can lead his hearers astray without ever 
being guilty of technical falsehood, so a writer in trans- 
ferring profound scientific speculations into a foreign 
tongue may discredit them without laying himself open 
to the charge of inaccuracy. The author, without ac- 
cepting the views of Mr. Crookes as a creed outside of 
which there is no salvation, admits that the pidure which 
he has drawn of the development of the chemical ele- 



ments is worthy of the highest attention. He considers 
that " whatever objedion the physicist may take, there 
is, from a purely chemical point of view, in the chain of 
thought neither a chasm nor a sin against recognised 
fads." He tells us, in his Preface, that *' there is pro- 
bably no single living chemist who, #. g,, assumes that 
e.g. cerium and lanthanum have always existed in the 
quantity now present." It appears to him quite inad- 
missible that each of the several elements of the earth's 
crust must have existed at all times in exadly the present 
quantities. ** Hence elementary mutations of matter 
must have occurred, or must still occur, in regions of the 
universe other than the small cold crust of our earth, 
mutations by which new elements have arisen and may 
arise from simpler materials." 

We cannot, however, help pointing out that both Mr. 
Crookes in his original discourse (p. a, line 3) and Prof. 
Preyer seem to assume— the former overtly and the latter 
by implication — that Prof. Mendeleeff recognises the 
evolutionary origin of the elements. 

Prof. Preyer contends further, in his Preface, that even 
if the entire cosmogonic hypothesis of condensation, 
rendered probable by Kant and Laplace, is superseded by 
something preferable, the discourse of Mr. Crookes has — 
for the present at least — a special value, on account of 
his peculiar method of utilising the method of fradional 
precipitation and of spedral synthesis. 

Prof. Preyer's preface will be valuable to German 
students as showing his exad position in reference to the 
views of Mr. Crookes, and to elemental evolution in 
general. 

We find here, also, a series of appendices of great in- 
terest. In the first of these, concerning elements and 
meta-elements (see a Discourse delivered by Mr. Crookes 
at the Annual Meeting of the Chemical Society, March 
28th, z888), Prof. Preyer writes:— ** A fad hitherto over- 
looked is in a remarkable connedion with the hypothesis 
of Prout, resting as it does on a purely evolutionary 
foundation. The atomic weights of hydrogen and the 
seven elements of the first stage of condensation (hence 
the eldest and those of the simplest strudure) come 
nearest to whole numbers (Li, G, Bo, C, N, O, F). In 
the elements of the second stage only four display this 
approximation ; in those of the third stage only three ; 
and in those of the fifth only two. Hence in the simpler 
elder elements the meta-elements play a quite subordinate 
part, but become more prominent in those formed subse* 
quently, as the hypothesis of Crookes would demand." 

A second appendix discusses the identical spedra of 
different substances. The identity of the spedra obtained 
by Crookes on a prolonged fradionated precipitation of 
the yttrium derivatives reminds him of the spedral 
identity of the hsemoglobines colouring the blood of all 
red-blooded animals. Prof. Preyer has found the absorp- 
tion spedra of the red blood-pigment of certain insed 
larvae (Chironomus), of a moUusk (Cardita sulcata)^ and 
the common earthworm (Lumbncui)^ are identical with 
the red blood-crystals of vertebrate animals. Notwith- 
standing this universal agreement in a fundamental pro- 
perty, the haemoglobines differ from each other physically 
and chemically. Their solubility, crystallisability, and 
their proportion of crystalline water differ. They crys- 
tallise in at least two systems. Their quantitative com- 
position, their coagulability, their liabili^ to decompose, 
differ according to the species. If species have been 
modified in the course of long eras, the hssmoglobines— 
though fulfilling all the conditions of a true chemical 
compound— must have become modified step by step with 
the species (in a morphological sense). Hence we see 
that the conception of evolution must necessarily find a 
place in chemistry, not merely as regards the elements, 
but as regards the formation of highly complicated though 
crystalline compounds. 

The scheme of the pedigree of the elements is ex- 
pounded and illustrated in a third appendix. 

A fourth appendix relates to Radiant Matter and the 



172 



Chemical Notices from Foreign Sources. 



f Chbmical News, 
1 Oa. 4. i89S' 



Phoftphoroscope, as displayed by Mr. Crookes at the 
Meeting of the British Association held at Sheffield, on 
August 22nd, 1879. 

The Organic Elements form the subje^ of a fifth 
appendix. Hence Prof. Preyer raises the question why 
only the organic elements, H, C, N, O, F, Na, Mg, Si,P, 
S, CI, K, Ca, and Fe, in the living vegetal and animal 
tissue, can keep up the vital process. He refers to the 
treatise " On Chemism in Living Protoplasm," by him- 
self and Wendt (See Himmel und Erde for October ist, 
189X ; Berlin, Hermann Pretel). 

The last appendix treats of Argon and Helium. Prof. 
Preyer thinks the assumption that argon is a modification 
of nitrogen not more improbable than that of its disco- 
yerers, who regard it as a totally new element. But he 
holds that there are no 6uch objections to the elementary 
charader of helium. In conclusion, he remarks that the 
main difference between our present systematic chemistry, 
on the one hand, and our present systematic natural 
history on the other, in comparison with the former che- 
mistry and natural history, is that we were formerly con- 
tent with artificial, i, e., arbitrary systems, whilst in our 
present systems we have to regard not merely that which 
now exists, but that from which it has been evolved. 
Such systems are not arbitrary, but natural, since they 
follow the course of Nature : they are genetic. 



Pofytichnic Instituti of Brooklyn, The Course in Prac- 
tical Chemistry, 
This prospedus gives an account of the equipment and 
organisation of the Brooklyn Polytechnic. Foremost 
stands a body called the*' Corporation" — equivalent, we 

f^resume, to the Senatus Academicus in German seats of 
earning. Next comes the '* Faculty," in which chemistry 
is not too copiously represented. There is only one Pro- 
fessor of the science, the widely-known Dr. P. T. Austen. 
The two '* InstruAors" in quantitative and qualitative 
analysis, and the assistants in chemistry, take apparently 
a lower rank. Some departments seem, on the contrary, 
to be over-represented. Thus we find a professorship of 
history and philosophy, a principal of the academic de- 
partment, a professorship of ancient languages, a profes- 
sorship of physical science and engineering, besides 
another of applied mathematics and engineering, and one 
of physics and eledrical engineering. Doubts may arise 
as to the respective boundaries of these departments. 

In the studies of the Chemical Course we find some — 
as it seems to us — superfluous matter, such as logic, 
moral philosophy, rhetoric, debates, perspedive. We fear 
that such an introdudion of extraneous matter will in- 
fringe upon the time and the brain-power needed for 
Science. We are glad to see that, in the laboratory work , 
of the Chemical Course, spe6rum analysis is not 
omitted. Nothing is said about microscopy and micro- 
biology. 

There is an illustration showing a corner of the library, 
the chemical ledure*room, the laboratory for qualitative 
analysis, in which the students have their faces all turned 
in one diredion, and of the laboratory for qualitative 
analysis. 

Wehave full confidence in the efficiency of Prof. Austen 
as the head of a chemical college, but we fear his hands 
will not be quite free. 

Programme of the Royal Technical High School at Aix- 
la-Chapille for the Year oj Studies 1895 — 1896. 
(** Program der Kdniglichen Technischen Hochschule 
zu Aachen.") Opening Odiober ist and ending July 
31st, 1896. Aix-la-Chapelle : C. H. Georgi. 
This eminent Polytechnic School continues to prosper. 
The number of students for 1894 — 1895 ^^^ 259 as 
against 236 in the previous year. The divisions are — 
I. Architedure; H. Constructive Engineering ; HI. Me- 
chanical Engineering; IV. Mining and Metallurgy, 



Chemistry, and Eledro-chemistry ; V. General Sciences, 
especially Mathematics and Natural Sciences. 

In Faculty IV. the professorial staff includes Dr. 
Andreas Arzruni (mineralogy and petrography), Dr. Lud- 
wig Claisen (organic chemistry). Dr. Classen (inorganic 
chemistry and eleC^ro-chemistry), F. Diirre (metallurgy 
and assaying), Dr. Holzapfel (palaeontology and geology), 
and Dr. Stalschmidt (technical chemistry). In addition 
there are two docents and ten assistants. 

In Faculty VI. we find that H. Storp gives instrudion 
in industrial hygiene, Dr. W. Miiller in first assistance in 
sudden accidents, and Anton Lieven, M.D., gives a course 
of practical bacteriology. 

The school has a mineralogical institute, comprising a 
museum and laboratory ; a laboratory for analytical and 
inorganic chemistry, including eleCtro-chemistry ; a labor- 
atory for organic chemistry ; a museum of chemical 
preparations ; a laboratory for technical chemistry ; a 
physical museum and laboratory; and a botanical in- 
stitute. 

The full course of study in each faculty extends over 
four years. The leCtures and the practical work in botany 
are compulsory only for '* food-chemists." 

During the autumn recess (August and September) 
there take place excursions to mines, metallurgical and 
chemical work, conducted by professors of the depart- 
ments concerned. No expert can examine this prospectus 
without being impressed with the complete and thorough- 
going character of the courses of instruction given at 
Aachen. It may even be questioned whether the courses 
of study prescribed are not in some cases so comprehen- 
sive as to sin against the principle of the division of 
labour. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NoTB.— All degrees of temperature are Centigrade anlett otherwise 
expressed. 

Comptes Rendus Hebdomadaires des Seattces, de VAcademie 
des Sciences, Vol. cxxi., No. 11, September 9, 1895. 
NitroSubstitutions.—C. Matignon and M. Deligny. 
— The authors give a comparative table of the combustion- 
heats with those of the substances in which substitution 
is effected, and they propose the law that the isomers of 
position have the same combustion-heat, excepting errors 
of experiment. It is therefore sufficient in these thermic 
studies to operate upon a single one only of the three 
terms, the ortho, meta, or para. The differences oscillate 
around 4*5 cal., and are sensibly constant. 

Explosion of Bndothermic Gases. — L. Maquenne.— 
Not suitable for useful abstraction. 

No.^i2, September z6, 2895. 
Researches on the Phosphates of Algeria. Case 
of a Pbosphatic Rock of Bougie presenting the Cona- 
positioQ of a Superphosphate. — H. and A. Malbot. — 
The authors have made a comparative study of several 
phosphates from the Department of Constantine, some of 
which are remarkable for their richness in phosphoric 
acid, such as thosk of Bordj-bou-Arreridg, and others for 
their friability, which renders them fit for immediate 
utilisation as plant food. The phosphatic rock of Bougie 
is extremely interesting, as containing phosphoric acid 
in three different conditions. The white portion con- 
tains 13*29 per cent of phosphoric anhydride soluble in 
water, 8'5Z per cent insoluble in water but soluble in 
ammonium citrate, and 11*70 per cent insoluble in water 
and in ammonium citrate; in all 33*50 per cent of phos- 
phoric anhydride. The red portion of the rock contains 
2*03 per cent of phosphoric anhydride soluble in water, 



Crbmical Nbws, I 

oa.4.1895. f 



Chemical Notices from Foreign Sources. 



*73 



and 12*39 per cent soluble in ammonium citrate. The 
white or exterior portion, after desiccation in the stove, 
loses 22*42 per cent at dull redness. Unless this is done, 
there is an error in deficiency if the phosphoric acid is 
determined by precipitation as magnesium-ammonium 
phosphate in a citric solution, as compared with the re- 
sult obtained by precipitation as ammonium phospho- 
molybdate. After ignition at a red heat the two methods 
agree absolutely. 

BtUletin dt la Sociiti CHmiauc dt Paris, 
Series 3, Volt. xiii.«xiv., No. 8, 1895. 

Cryatalline Compouiid of Ferrous Chloride with 
Nitric Oxide.— V. Thomas. 

Ammoniacal Salts of Silver.— A. Reychler. — The 
author gives a table showing the results of his cryoscopic 
experiments on these salts, proving that the addition of 
a mols. ammonia per equiv. of silver or copper scarcely 
at all modifies the molecular lowering of the congelation- 
point. He adds theoretical considerations on the con- 
stitution of the ammoniacal silver salts. 

AtfUon of Formic Aldebyd upon the Amines and 
on their Salts.— R. Cambier and A. Brochet. 

Hesachlorobenzens Parabicbloride. — £t. Barral.— 
The decomposition of carbon chloride, CeCls, by heat or 
by the majority of reagents into hexachlorobenzene and 
chlorine, CeCls^CeClfi+Cla, shows that it is an addition 
produd of hexachlorobenzene, in which the position of 
the two CI is given by (i) its transformation mto tetra- 
chloroquinone under the influence of oxidising agents ; 
(2) its preparation by means of tetrachloroquinone and 
phosphorus pentachloride. 

Constitution of a - Hexachlorophenol and of 
Quinone. — Et. Barral. — The author shows that the 
formula of Fittig gives the constitution of quinone, and 
that it is a diketone, possibly of a peculiar kind. 

Basic Properties of the Rosanilines and their Sul* 
phonic Derivatives. A Reply to M. Prudhomme. — 
A. Rosenstiehl. — The author explains the formulae which 
he has assigned to acid magenta and to sulphonic rosani- 
line. He shows what he has said in his former publica- 
tions of the basic fundions of the rosanilines, and he 
lastly examines whether the magentas should be regarded 
as ethers or as salts. 

Are the Magentas Ethers or Salts ? — A. Rosenstiehl 
— There exists in the derivatives of triphenylmethane an 
assemblage of compounds in which the alcoholic fundion 
varies in a continuous manner between two extremes, as 
in the mineral oxides the acid function and the basic 
fuodioo vary, though it is not easy to draw a boundary. 
To unite the formulae of an ether and to call it a salt is 
to collide against a word. 

Analysis of the Gastric Juice.— J. Winter. 



Rome Unhrrsel/e (Us Mines et de la Metailurgie, 
Series 3, Vol. xxx.. No. 3. 
Rapid Determination of Phosphorus in Steels.— 
The most pradical procedure consists in transforming the 
phosphorus into phosphoric acid, precipitating it with 
molybdic reagent, and determining the apparent volume 
of the precipitate after having effected its rapid settlement 
and its regular heaping up by means of centrifugal force. 
Thia method, proposed by Eggertz in x86o, was not at 
fir^t appreciated as it deserved, but since 1887 it has been 
studied and improved, and is now in regular use. Various 
authors describe methods of operating slightly different. 
Von Jiiptner proceeds as follows:— He weighs out, for 
medium proportions, 2 grms. of the sample (more for low 
percentages, and less for highly photphidic steels), dis- 
solves in 30 c.c. of nitnc acid (sp. gr. 1*2), completes the 
oxidation by means of permanganate, and then causes 
the manganic precipitate to disappear by means of a 



small quantity of oxalic acid. To the solution is added 
075 grm. of ammonium nitrate, the mixture is heated to 
60°, and treated with 50 c.c. of the molybdic solation. 
The temperature is kept at 60^ until the precipitation is 
completed, and then left to settle until the liquid is per* 
fe^ly clear. The liquid is decanted, and the precipitate 
is washed into a special vessel by means of a washing- 
bottle charged with ammonium nitrate. The receiving 
vessel is contraded at its lower part and terminates in a 
narrow tube graduated in cubic millimetres in which the 
precipitate is coUedted. The graduated vessels, thus 
charged, are introduced into a small turbine, which is set 
in motion at the rate of 1000 rotations per minute, a speed 
which is kept up for four minutes. After stopping the 
rotation, the volume of the precipitate is read off on the 
graduated tube. If the surface of the precipitate is not 
perpendicular to the axis of the graduated tube, we read 
the level of the lower part and that of the upper part 
and take the mean. To find the proportion of phosphoric 
acid in the steel assayed from the volume of the precipi- 
tate, Ledebur gives the figure of 0*0025 P^^* cent per cubic 
millimetre, when operating on 0*882 grm. of steel, which 
is equivalent to 0*0022 per cent if we operate upon i g^m., 
or o'ooii for 2 grms. 

ZtUschrift fur Analyiisthi Chemie, 
Vol. xxxiv.. Part 3, 1895. 

Contributions to the Analysis of Must and of 
Wine. — A. Halenke and W. Moslinger. — This paper is 
too voluminous for insertion. 

Contributions to the Isolation, Quantitative Sepa- 
ration, and Chemical Diagnosis of Alkaloids and 
Qlykosidous Substances in Forensic Cases, with 
especial reference to their Detedlion in Putrescent 
Human Bodies.— Dr. Kippenberger.— This memoir also 
does not admit of abstradion. 

New Process (or the Determination of Indigotin. 
— Josef Schneider (Casopis pro Prtimysl Chimicky, 1893). 

Remarks on the Sweet Wines of Austria-Hungary. 
— Leonhard Roesler. — A memoir not calculated to interest 
our readers. We mention merely the fadl that more than 
half of the samples of Tokay and analogous wines con- 
tain per litre more than 0*55 grm. of phosphoric acid. 

Determination of Sulphur and Chlorine by means 
of Sodium Peroxide. — A. Edinger. 

New Method of Separating Copper and Cadmium 
in Qualitative Analysis.— AUerton S. Cushman.— 
Already inserted. 

Analysis of the Nitrogenous Components occur- 
ring in Meat Eztra^s and in Commercial Peptones. 
— A. Stutzer. 

Dete<5tion and Determination of Metals in Patty 
Oils.— H. Fresenius and A. SchattenCroh. 



MISCELLANEOUS. 

City and Guilds of London Institute.— At the re- 
cent Matriculation Examination of the City and Guilds 
Central Technical College, 76 candidaten presented them- 
selves, and 62 have been admitted to the College. The 
highest place was taken by M. Solomon, to whom the 
Clothworkers* Scholarship of £60 a year and free educa- 
tion has been awarded. 

Spontaneous Combustion of Wool. — It is not 
sufficiently known that wool, if packed in bales whilst in 
a damp state, is, like cotton, liable to what is called 
spontaneous combustion. The adiun is not as violent in 
wool as in the case of vegetable fibre, and it has never 
yet been known to spread to other kinds of goods in the 
same ship or warehouse. But wool sometimes arrives in 
England scorched, and seriously deteriorated in value. 



174 



New Safety Paraffin Lamp. 



{Crbmical lliwt. 
oa.4.1895. 



Steam-BoUer Etplosions.— Daring the year 1894 no 
fewer than 35 such calamities occurred in Germany. The 
number of the infferers was 3^, of whom 12 were killed, 
o severely wounded, and 13 slightly injured. The most 
frequent causes are said to have been insufficient supply 
of water and local weakness of the plates from age. — 
Chimikif Ziitung. 

New PoitODS.— The Cape Agricultural youmal is 
calling attention to a poison not yet fully understood. It 
is obtained from Acocanitura vtmnaia (or Tpxieophlaa 
ThunbirgiH, known to the colonists as Gift-boom or 
Poison*tree. The leaves have proved rapidly destruaive 
to many soats, and a decoAion of the bark of the root is 
used medicinally by the native quacks, sometimes with 
fatal effed. In one case, where the m^icine was admi- 
nistered as an enema, death ensued in about two minutes. 
It is conjeAured that the a^ive principle is not an 
alkaloid, but a glucoside. No analysis of the poison has 
been published, nor have its readions been studied. The 
arrow-poison used by the Bushmen is said to be prepared 
by mixing the venom of the African cobra with the gum- 
resin which exudes from the rhizomatous base of the 
" gift-boll,*' Brunsvigia toxicaria. Whether the latter 
ingredient has any effed beyond preventing the cobra 
poison from bein^ rubbed off the point of the arrow has 
yet to be ascertained. 

Max Dreverhofi'a Filter-papers.— We have received 
from Max Dreverhoff, of Dresden, a price-list and a num- 
ber of samples of excellent filter*papers. No pains 
appear to have been spared to produce papers to meet 
the requirements of all departments of chemistry. M. 
Dreverhoff has succeeded very well in the great aim of 
all manufadurers of filters, to produce a paper that will 
allow liquids to pass rapidly and at the same time retain 
very fine precipitates. We notice the special filters that 
have been treated with HCl and HF : these appear to be 
quite strong, and a 9 cm. circular paper on incineration 
leaves only 0*00006 grm. of ash. Filters of this quality, at 
the very reasonable prices at which they are offered, will 
prove a great boon to the chemist. We also note the 
ready-folded filters as being neatly made, and not un- 
reasonable in price. M. Dreverhoff*s price*list is very 
complete, giving minute particulars of all his manufac* 
tares, and, for the greater convenience of foreign cus- 
tomers, some of the more important announcements are 
given also in French and English; but in this latter 
endeavour the writer.has unfortunately got a little mixed 
—for after various slips in the body of the list, he gravely 
expresses a belief that " the filters must satisfy the 
highest pretensions of the most painful analytical 
chemist.'^ We trust they will prove of better quality 
than the English. 

A New Safety Paraffin Lamp. — We are glad to find 
that manufadurers are becoming alive to the dangers that 
accompany the majority of cheap paraffin lamps, and, 
taking warning from the terrible accidents that are too 
frequently recorded, especially in the houses of the 
working classes, are bringing to the front lamps that are 
within the reach of all, and are at the same time de- 
signed upon true principles with a view to reducing, as 
far as possible, the risk of accident accompanying their 
use. In this direAion the little lamp that has been 
sent to us by Messrs. Kiesow and Co. is a happy 
example. The reservoir is made entirely of metal, fur- 
nished with two convenient handles (the value of which 
is often overlooked) ; the burner, instead of fitting into 
the oil-chamber with the usual loose screw, has a simple 
and efficient bayonet fitting. An ingeniously devised 
8-shaped tube, attached to Uie burner, carries the wick 
down into the body of the reservoir, diminishing to a 
ffreat extent the danger of the oil escaping in case of the 
lamp getting overturned. On the whole we consider the 
lamp to be a good step in the right dire^ion, and hope 
it will meet with the appreciation it deserves. 



NOTES AND QUERIES. 



*«* Oor Notes and Queries colamn wu opened for the purpose of 
fiviog and obtaining information likely to be of aie to our readers 
generally. We cannot undertake to let this colomn be the means 
of tranimittiog merely private information, or inch trade notioee 
as shoald legitimately come in the advertisement oolnmoe. 
Assaying.— Can any of yonr readers tell me of any book snitable 

for the pramcal aeeaying of toch things as brass ashes, aioc ashea, 

type ashes, tin ashes, ftc.? I have ** Beringer," bot he does not treat 

of these.— S. J. HaBeooD. 



J. & A. CHURCHILL, 
PUBLISHERS. 



PRACTICAL CHEMISTRY AND 

QUALITATIVE ANALYSIS : Soecially adapted for CoUegts 
and Schools. By PRANK CLOWBS, D.Sc, Piofettor of Che- 
mistry in University ColU — • - 
84 Engravings, Post 8vo, 



ana ocovois. oy r aaxviv ^LtUWdOf u.oCm rroiespor oi i#iic- 
mistry in University College, Nottingham. Sixth Edition, with 



ELEMENTARYQUALITATIVBANA- 

LYSIS: suitable for Organised Science Schools. By FRANK 
CLOWES, D.Sc. Lond., ProfcMor of Chemistry in Universtty 
College, Nottingham, and J. BERNARD COLEMAN. Head of 
the Chemical Department, South- West London Polytechnic. 
With Engravings. Post 8vo, 21. 6i. 

BY THE SAME AUTHORS. 

QUANTITATIVE ANALYSIS: specially 

adapted for Colleges and Schools. Third Edition, with 106 En- 
gravings, Post Bvo, 9s. 

VALENTIN'S QUALITATIVE ANA- 

LYSIS. Edited by Dr. W. R. HODGKINSON, F.R.S.E., Pro- 
fessor of Chemistry and Physics in the Royal Military Academy 
and Artillery College, Woolwich. Eighth Edition, Revised and 
Enlarged, 8s. 64. 

BLOXAM'S CHEMISTRY, INOR- 

GANIC AND ORGANIC, with EaperimenU. Re-writteo and 
Revised bv JOHN MILLAR THOMSON, Piofessorof Chemia- 
try, King^s College, London, and ARTHUR O. BLOXAM, 
Head of the Chemistry Department. The Goldsmiths' Institate* 
New Crou, London. Eighth Edition, with 281 Engravinga, 8vo, 

BLOXAM'S LABORATORY TEACH- 

ING; Or, Progressive Exercises in PraAical Chemistry. 
Edited by ARTHUR G. BLOXAM, Head of the Chemist^ 
Department. The Go dsmiths' Institute, London. Sixth Editioa. 
Revised and much Enlarged, with 80 Woodcnts, Crown 8vo, 
6s. td, 

CHEMISTRY OF URINE; a Practical 

Guide to the Analytical Examinations of Diabetic. Albuminous, 
and Gouty Urine. By ALPRED H. ALLEN, F.I.C., P.C.S 
With Engravings, 8vo, 7s. 6d, 



London : 
J. & A. CHURCHILL, 11, Nbw Burlington Strbbt. 



TO MANUFACTURING CHEMISTS. 

qPHE LONDON COUNTY COUNCIL is 

•^ prepared to receive Tenders for the Supply and Delivery at the 
Barking and Crossness Outfall Works of S350 Tons of PROTO* 
SULPHATE OP IRON (Commercial Green Vitriol). Persona 
desirins to submit tenders may obuin the Form of Tender and other 

Sirticulars on application at the Engineer's Department, Connty 
all, Spring Gardens. Tenders must be upon the official forms, and 
the printed mstruAions contained therein must be striAly complied 
with. Tenders are to be delivered at the county Hall in a sealed 
cover, addressed to the Clerk of the London County Couodl, and 
marked ** Tender for Proto-Sulphate of Iron.'* No tender will be 
received after xo a.m. on Tuesday, the i<th Oaober, 1805. Any tender 
which does not comply with the printed instraAiooa tor tender may 
be rejeAed. 

The Council does not bind itself to accept the lowest or any tender, 
and it will not accept the tender of any person or firm who shall 00 
any previous occasion have withdrawn a tender alter the aame baa 
been opened, unless the reasons for the withdrawal were aatiafaAoiy 
to the Council. 

H. 01 LA HOOKE, Clerk of the CooaciJ. 
Spring Gardens, S.W., 
a7th September, iSgS' 



y 



CsnocttNiw*,! 



Action of Light upon the Soluble Metallic Iodides 



»75 



THE CHEMICAL NEWS 

Vol. LXXII., No. 187a. 



THE ACTION OF LIGHT UPON THE 

SOLUBLE METALLIC IODIDES IN PRESENCE 

OF CELLULOSE.* 

Bj DOUGLAS J. P. BBRRIOOE, B.A., llalvero CoUefo. 

The lAioB of light apoo the metallic iodides appetrt not 
to have been thorooghly investigated by any chemist, 
and, althongh it has frequently been taken for granted by 
eome eipenmenters that potassium iodide suffers decom- 
position when exposed to sunlight, others have passed the 
•ttbjeft over in silence, and, so far as I am aware, no 
text-book upon chemistry mentions the U6t. The experi* 
ments, sn account of which I have to-day to lay before 
the Seaion, were commenced in the year 1884, and it was 
not until eight years later, daring most of which mterval 
I had been prevented from finishing my work, that I heard 
of Videau*s investigations ; in 189a I came across a notice 
of them in Prof. Meldola's book, •* The Chemistrv of Pho- 
tography,'* but as, by a reference to the original paper, I 
found that Videau had worked upon an altogether different 
principle from my own, and his results left much to be 
cleared op, I have continued to prosecute my experiments. 
Last year a paper was read before the Chemical Society, 
by Dr. Cook, upon the tfMt of heat upon iodates and 
bromates, in the course of which he mentions {y. Chim, 
Soc.t 1894, p. 804) that ordinarv purified potassium iodide 
'* liberates iodine when exposed to air and light," but that 
if the iodide be previously purified by crystiUlisation from 
abeolute alcohol no such decomposition takes place. Dr. 
Cook does not mention in his paper the precautions he 
took to prevent the access of carbon dioxide from the air 
to his solution, which was contained in a test-tube, and 
as impurities would be probably more abundant in the 
open air than in a dark cupboard it seemed to me, after 
reading his paper, that a more satisfadory method of ex- 

Kriment would be to seal the solution of the iodide in a 
lb with a known quantity of air, thus preventing any 
COj from reaching the liquid and disturbing the results. 
I may, however, say at once that after doing this my ex- 
periments fully confirm Dr. Cook's. Solutions of the so- 
called pure salt, which, when tested with starch and 
tartaric acid, gave no immediate colouration, were 
always decomposed when exposed in sealed tubes con- 
taining air to the sunlight ; the amount of iodine liberated, 
however, varied considerably ; on the other hand, a solu- 
tion made with potassium iodide which had been pre- 
viously fixed with charcoal gave no colouration upon the 
addition of starch, even after an exposure to sunbght for 
■everal weeks. 

It is, however, to the decomposition of the iodide in 
pretence of cellulose that I more especially wish to call 
your attention ; in the earlier experiments my method was 
to saturate a sheet of psper with a solution of the desired 
iodide, and to expose this to the sunlight in a printing 
frame under a negative ; in my later experiments I have, 
however, confined myself to the use of sealed bulbs, 
since by this method only can any qoantiutive results be 
obtained. I at first exp<^enced a certain amount of diffi- 
culty in obtaining a form of cellulose suited for the pur* 
pose, and many experiments in which cotton-wool was 
used fsiled, owing to the presence of sodium thiosulphate 
in the material, from which it could only be removed with 
great difficulty. When, however, I substituted filter- 
paper which had been exUaAed by hydrochloric and 

• R«ftd btfbrt the British AitociatioD (S«aion B), Iptwich 
Msscioc, tSM* 



hydrofluoric acids for the cotton- wool, much more satis* 
fador^ results were obtained. The paper used was that 
supplied by Schleicher and Schtill, and was in aU cases 
tested for acid, from which it was, however, ptrfedly free ; 
after reducing a certain quantity of this paper to pulp, 
and well washing with distilled water, it was introduced 
into a bulb ; the solution of potassium iodide, generally 
containing a known weight of the salt, was added, and 
the bulb sealed. After exposuro to sunlight the bulbe 
were opened, a little starch added, and the amount of 
iodine liberated determined by a ceatinormal solution of 
thiosulphate of sodium. 

In a typical experiment 85*7a4 grms. of potassium 
iodide wera dissolved in 500 cc of distilled water and five 
sheets of the puro filter-paper, xa'< cm., treated as 
described, were introduced into a bulb of about 100 cc. 
capacity and 50 cc. of the iodide solution added. la 
another bulb, of the same sise, 50 cc of the solotioo 
were sealed without the addition of pulp. After an ex* 
posure of about four hours to diffused sunlight, the former 
had acquired a decided reddish colour, whilst the latter 
remained perfedljr colourless ; at the end of twenty-five 
days, during which ihe bulbs bad been exposed in a 
window, they were opened, when 0*00x778 grm. of iodine 
was found to have been liberated in the former, whilst ia 
the latter only 0000635 S^m. of free iodine was found. 

When a solution of half the above strength was used, 
U,^ one contsining 4*a86 grms. of potassium iodide dis- 
solved in 50 cc. of distilled water, the influence of the 
cellulose was even more marked, for in the bulb coouin- 
ing 50 cc. of solution and five sheets of extraded paper 
o*ooz^a4 grm. of free iodine was found, whilst io one 
containing the same quantity of solution but no pulp, 
only 0*000x91 grm. of iodine had been liberated. In a 
fifth bulb the same quantity of paper pulp was placed, 
and the solution of potassium iodide was poured off after 
the pulp had become thoroughly soaked with it. In this 
case the liberation of iodine occurred much sooner than 
in the previous cases, but considersbly less was liberated 
during an exposure of five and twenty days, the total being 
only o*ooo76a grm. The contents of sll these five bulbs 
were tested for slkali with a solution of phenolphthalein ; 
the two in which there was no pulp gave decided colour- 
ation with this resgent, whilst the three containing cellu- 
lose proved to be quite free from alkali. 

In another series of experiments a stronger solution of 
potassium iodide was used, vis., one containing 76*936 
grms. of the salt dissolved in i$o cc of water, and this 
waa sealed in bulbs containing a varying quantity of the 
paper pulp. Four bulbs were taken ; in the first, half a 
sheet of paper reduced to pulp was placed, in the second 
one sheet, in the third two sheets, and in the fourth four 
sheets ; 40 cc. of a solution of the strength above 
described, and therefore containing xa*3o8 grms. of the 
salty were added. These were exposed in a window for 
ten davs, at the end of which time the followtag resulu 
were obtaiaed upon analysis :~ 

Bulb A. 



B. 
C. 
D. 



0*00x397 grm. iodine, trace of alkali. 
0-00x935 „ 
o*ooaa86 „ 



, no free alkalL 

oooa54 „ „ 

As far as it was possible to judge from the colooratioo of 
the pulp, all these bulbs had liberated their maximum 
quantity of iodine some days before analysis. It will be 
noticed that the total weight of iodine liberated is very 
small in the above instances, never exceeding o'oay per 
cent of the total iodine present, or x*xao per cent of the 
quantity the oxygen in the bulb was able to liberate. 

In an experiment made with potassium iodide which 
had been previously fused with charcoal, about 30 grms. 
of the salt were fused and dissolved in xoo cc of water. 
40 cc. of this solution was sealed in a bulb, and found 
after twenty-five days to be entirely free from iodine ; 
50 cc. were sealed in another bulb with five sheeu of 
paper reduced to pulp, and in this case alter the eaae 



176 



Action 0/ Light upon the Soluble Metallic Iodides. 



I CBSMXCAL, NBWt, 

I oa.zi, 1893. 



exposure 0*001651 grm. of free iodtoe was found, the 
liquid being free from alkali. 

If the air above the iodide solution in the tube is dis- 
placed by means of oxygen more iodine is liberated, and 
the maximum effe^ seems to be reached earlier ; but I 
have not at present made sufficient experiments to trace 
any relation between the total quantity of oxygen present 
and the amount of iodide decomposed. Hydrogen, on 
the other hand, reduces the quantity of la liberated, and 
if the oxygen is entirely removed from both the bulb and 
the solution I have no doubt that the iodide would remain 
perfeAly undecomposed, although at present I have not 
•necked in obtaining this theoretical result. 

The equation for the reaAion is most simply written :~ 

2KI+HaO+0»2KOH+Ia. 

I hope to show presently that this does not completely 
represent the reaAion, but, allowing that it gives the first 
stage of the decomposition, the reason for the very 
marked increase in the quantity of iodine liberated when 
cellulose is present becomes apparent, for the iodine set 
free by the above rea^ion should, and doubtless to a con- 
siderable extent does, re-combine with the potassium 
hydrates formed, producing a mixture of iodide and 
iodate. If, however, any substance is present which will 
combine with the alkali, removing it from the sphere of 
aAion, the oxidation is enabled to proceed without the 
subsequent combination of the liberated iodine. The 
absence of alkali in the solutions containing sufficient 
cellulose, and its presence when cellulose is either absent 
or present in small quantities, seems conclusive evidence 
that the increase in the amount of the iodide decomposed 
in presence of this substance is due to the removal of the 
alkali. 

In order to obtain prints on paper by the decomposition 
of potassium iodide, I at first used a frame like that sold 
in toy-shops as a drawing-slate; more recently, however, 
I have used one exadly like the ordinary photographic 
printing- frames. The paper must not be too absorbent, 
and one with a smooth surface answers best ; although I 
have been able to obtain fine proofs from ordinary nega- 
tives, the detail is too rough for these to be satisfadory, 
and consequently I have generally employed a negative 
made by cutting out a device in paper, fastening this to a 
sheet of glass, and varnishing. The best strength for the 
solution appears to be one containing about i part of the 
salt dissolved in 8 parts of water, a weaker solution re- 
quiring a much longer exposure, whilst if a stronger 
solution is used the ground of the resulting print is apt 
to become too dark. If a sheet of note-paper is moistened 
with the solution, and at once placed in the frame, it 
will, in about five minutes in diffused daylight, become 
printed in a light chocolate and pink colour, with the 
device cut out of the negative ; if the exposure is pro- 
longed the colour becomes much darker, and at the same 
time, owing to the spontaneous decomposition of the salt, 
the parts unexposed to the light become more or less 
deeply tinted ; the exposed part is, however, always so 
much darker than the rest that the print stands out well. 
If the paper is allowed to dry in the dark after being 
saturated, it assumes a faint chocolate tint, and when 
placed in the frame and exposed for about four hours be- 
comes printed in a dark chocolate, although it shows no 
signs of darkening for some time after a similar sheet of 
damp paper has become deeply marked. If a piece of 
paper, after being printed to a chocolate colour, is 
moistened with water, the colour of the print at once 
changes from chocolate to blue, and even if it is still 
damp when removed from the printing- frame the colour 
is never blue until water has been added to it. In order 
to arrive at some definite conclusion concerning the 
nature of the change occurring, I attempted, by means of 
a solution of iodine, to imitate the colour produced during 
exposure of the saturated paper to light ; using at first a 
aolution of iodine in an aqueous one of potassium iodide, 
I obtained, when it was poured over a sheet of writing- 



paper, a stain which varied according to the concentration 
of the solution from blue to bluish-black ; even when the 
solution was so dilute that in some lights it was difficult 
to see any mark, the stain upon the paper was always 
blue. I next used solutions of the element in benzene, 
carbon disulphide, chloroform, and alcohol : when these 
solutions were poured over paper, stains were produced 
which varied with the strength of solution from 
yellowish. brown to walnut. In other words, whilst the 
colour of the exposed paper was always tinged with 
pink in all attempts to imitate this, I obtained a blue 
colour if I used an aqueous, or a yellow colour if I used 
an anhydrous, solution of iodine. 

I may here mention that all the note-paper I have ex- 
amined contained starch, and that this solution only pro- 
duces the well-known so-called iodide of starch in the 
presence of water; this latter fad may be shown by 
passing an anhydrous solution of iodide over paper 
coated with starch, when a brown stain is produced, 
which becomes blue, however, upon the addition to it of 
water. This explained the difference in the colour of the 
stains produced in the various solutions of iodine, but it 
did not help to indicate the adlion of light upon the potas- 
sium iodide ; in fad, it made it rather more difficult, as it 
appeared to show that the colour of the prints was not 
due to the presence of free iodine ; the only probable con- 
clusion was, therefore, that the iodine combined at the 
moment of liberation with the still unaltered potassium 
salt, forming the tri-iodide or some similar compound. 
If this compound colours paper a pinkish chocolate, and 
is decomposed into its constituents by water, an explana- 
tion is at hand to account for the observed phenomena. 
To test whether this was the case, a little iodine was 
added to a solution of starch, and to the blue liquid thus 
obtained a concentrated solution of potassium iodide was 
added ; the colour, however, remained unaltered, and after 
a large number of experiments I came to the condusiofi 
that the amount of water necessary to bring the starch 
into solution was more than enough to decompose any 
higher iodide which might be found ; the experiment was 
therefore varied by adding to a piece of solid starch which 
had been coloured pink by the addition of iodine in 
alcoholic solution a few drops of a saturated solution of 
potassium iodide ; the colour of the starch deepened, but 
did not turn blue. I then took apiece of paper which was 
coloured blue by the presence of a small quantity of starch 
iodide, and added to it a very concentrated solution of 
potassium iodide ; the blue colour changed to one approxi- 
mating very closely indeed to that obtained by the aftion 
of light upon the iodised paper. This experiment seemed 
to justify the hypothesis that the colour of a piece of 
iodised paper after exposure is due to the presence of 
potassium tri-iodide or some similar compound. 

In order to fix a print obtained upon the iodised paper, 
it is washed for a short time in running water; if the 
washing be too long continued, or if the paper be allowed 
to remain in a dish of water, the iodine dissolves and the 
proof is, of course, lost ; lead acetate in very dilute solu- 
tion is now poured over the paper, which is then again 
washed. If the print fixed in this manner is left it will 
begin at once to fade, and in a few days, or even hours, 
no trace of the design will be visible ; if, however, a coat 
of size is put over it, and this followed by one of a hard 
varnish, the stability of the print is very much increased, 
and I have specimens which are more than three years old 
and are still distind. 

I have up to this point mentioned only the behaviour of 
potassium iodide when exposed to light, as the salt is the 
most easily obtained in a comparatively pure condition ; 
it is the one with which I have chiefly worked. I have, 
however, made qualitative experiments upon the iodides 
of sodium, calcium, strontium, barium, sine, cadmium, 
and iron. 

Sodium iodide was bought as pure, and was probably 
no more impure than the ordinary potassium salt ; it 
yielded a print of the same depth of colour as that ob- 



C»«inc*l.MBWt,\ 
Oa. II, 1895. I 



Chemical Researches and Spectroscopic Studies. 



177 



Utned from potMsiam iodide in considerably less time. 
As far, however, as coald be jadged from qualitative ex- 
periments, the maximum iodine was liberated about the 
same in each case. 

Calcium, strontium, and barium iodides were obtained 
by adding the metallic carbonate to hydriodic acid which 
was free from iodine ; the solutions, after filtering, were 
neutral and gave no colouration with starch. 

Barium iodide gave a decided print in about ten minutes, 
and after an exposure of about two hours a strong print 
was obtained, which was, as in the case of the potassium 
salt, at first chocolate-coloured, turning blue on the addi- 
tion of water. 

Strontiom iodide appears to be more sensitive to the 
adion of light than the barium salt, a strongly-coloured 
proof being obtained after an exposure of about an hour. 

Calcium iodide appears to be even more sensitive to the 
light than the strontium salt; in fad, the amount of 
ic^ioe liberated seemed to vary roughly inversely as the 
atomic weight of the metal with which it is combined. 
I have experiments now in progress with a view to testing 
this. 

Zinc iodide was obtained by placing 4 grms. of iodine 
in a flask together with metallic zinc and a little water. 
After standing in a warm place for a couple of days, the 
colour of the solution was discharged and when filtered 
and at once tested for iodine, it proved to be free from 
this element. The solution was made up to about 50 
c.c, and paper was saturated with it as in the previous 
experiments. In all cases distind proofs were obtained, 
bat as the solution is exceedingly unstable, the unexposed 
portions were much discoloured, making the device more 
difficult to read. 

Ferrous iodide was obtained in a similar manner to the 
sine salt ; iron-filings and iodine being warmed together, 
the filtered liquid was colourless, and gave no colouration 
with starch. It is, apparently, less sensitive to the adion 
of light than the other soluble iodides, but I have obtained 
distinA prints when using it. The exposed parts are, of 
conrte, as in the case of the sine salt, much discoloured 
owing to the spontaneous decomposition of the compound. 

Cadmium iodide differs from all the other iodides I 
have examined, inasmuch as it gives a blue and not a 
pink print, it would thus appear that this element alone 
It unable to form a higher iodide. 



THE RBSPIRABILITY OF AIR IN WHICH A 

CANDLE-FLAME HAS BURNT UNTIL 

IT IS EXTINGUISHED.* 

By FRANK CLOWES, D Sc. 

At the last meeting of the British Association the author 
stated the composition of artificial mixtures of nitrogen 
and of carbon dioxide with air, which were just able to ex- 
tinguish various flames. It was found that the flames of 
ordinary candles and lamps were extinguished by mix- 
tures which contained on an average about 16*5 per cent 
of oxygen and 83*5 per cent of the extindive gases. A 
flame of coal gas, however, required for its extinAion a 
mixture still poorer in oxygen, and containing 11*3 per 
cent of oxygen and 887 per cent of the exti naive gases. 
Thete results have since been confirmed by a different 
method. 

The method consisted in allowing the flames to burn 
in air inclosed over mercury until they were extinguished; 
the remaining extindive atmosphere was then subjeded 
to analysis, when its composition was found to be praAi- 
cadly identical with that previously obtained from the 
artificial mixtures. An analysis of air expired from the 
lungs proved that it was also of the same composition as 

* Read before the Biitish Aiiociatioa (Seaion B), Ipawicb 
Mcstiiiffi 1895. 



that which extinguished the flame of an ordinary candle 
or lamp. 

The average percentage composition of expired air 
and of air which extinguishes a candle-flame is as fol- 
lows :— Oxygen, 15*9 ; nitrogen, 80*4 ; carbon dioxide, 3*7. 

Now an atmosphere of this composition is undoubtedly 
respirable. Physiologists state that air may be breathed 
until its oxygen is reduced to xo per cent. The maximum 
amount of carbon dioxide which may be present is open 
to question, but it is undoubtedly considerably higher 
than 3 per cent. Dr. Haldane maintains that the above 
atmosphere is not only respirable, but would be breathed 
by a healthy person without inconvenience of any kind ; 
he further states that no permanent injury would result 
from breathing such an atmosphere for some time. 

The conclusion to be drawn from these fads is, that an 
atmosphere must not be considered to be dangerous and 
irrespirable because the flame of an ordinary candle or 
oil-lamp is extinguished by it. The view is very generally 
advanced that a man must on no account venture into air 
which extinguishes the flame of a candle or of a bundle 
of shavings. It will be seen that this precaution may 
deter one from entering an atmosphere which is perfedly 
safe and respirable, and from doing duty of a humane or 
necessary charaaer. 

An atmosphere which extinguishes a coal-gas flame, 
however, appears to approach closely to the limit of 
respirability, as far as the proportion of oxygen which it 
contains is concerned. Hence the coal-gas flame appears 
to be a more trustworthy indicator of respirability than the 
flame of a candle or oil-lamp. 

Undoubtedly the candle and lamp flames should be dis- 
carded as absolute tests of respirability of air. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By JEAN SBRVAIS STAS. 

[Thb complete works of the late J. S. Stas have recently 
been published at Brussels. They contain several me* 
moirs on important points of chemistry and physics which 
are there published for the first time. Among these none 
equal in interest that entitled ** Recherches Chimiques et 
Etudes Spearoscopiques sur diff6rents Corps Simples.'* 
In the following pages we commence the translation of 
this memoir, and we propose to continue its publication 
from week to week till completed]. 

Chapter I. 
Chemical Researches and Spectroscopic Studies op 

Sodium, Potassium, Lithium, Calcium, Strontium, 

Barium, and Thallium. 

Introduction, 

In undertaking these chemical works and spearoscopic 
studies, my objea was to ascertain whether I could cause, 
by increasing the temperature or the intensity of the elec- 
tric current, and contrary to what is generally admitted, 
a correlation among the charaaeristic bands of the lumi- 
nous speara of compounds of sodium, potassium, lithium, 
calcium, strontium, barium, and thallium, in such a state 
of purity as the improvements in the methods of chemical 
analysis permit me to aaually obtain these bodies. 

I was well aware that if my experiments failed, after 
having taken great pains* and having devoted to this 
work an amount of time which I might pet haps have used 
more profitably, I should add nothing to the sum of our 
spectroscopic knowledge. Still, I should free science (rom 
an hypothesis which has led astray, and may again lead 
astray, many clever men ; it seemed to me that this was 
just as much helping to advance nal knowledge. 

Chemical analysis is generally recognised as being 



178 



Chemical Researches and Spectroscopic Studies. 



fOHBUICALMlVt, 

1 oa. XI, 1895. 



unable to deted the presence of sodium, still less to find 
the percentage of this metal, when it exists in a very small 
proportion in a given compound. 

Smce the memorable works of Messrs. Hansen and 
Kirchhoff on spe^rum analysis, chemists have almost 
invariably used this method of deteding the presence of 
•odium. 

Whilst applying their method to the examination of 
soluble compounds obtained by the mtihod of fractional 
erystallisatioHS, the illustrious authors have found that, 
by this process, one can never entirely separate the sodium 
from the body with which it is mixed ; one must employ 
simultaneously a chemical readkion by which one can ob- 
tain an absolute separation. M. Buosen and then M« 
Diehl were the first to pradise this method, the latter on 
the advice of his illustrious master. 

The occurrence of the sodium line in the spedrum of 
nearly all compounds led Mr. Lockyer to believe that this 
metal is evolved by the dissociation of the elements of the 
bodies on which one is working. This hypothesis, if it 
were verified, would necessitate the overthrow of all the 
fundamental notions of the physico-chemical sciences. 

However improbable it has appeared, as regards the 
majority of chemists who have done accurate work, the 
name of Mr. Lockyer, and the brilliant services which he 
has rendered to science by his ^pedroscoptc researches, 
have induced me to submit his hypothesis to a critical 
examination, about which he has done me the honour of 
writing to me (1878). 

The work that I have undertaken with potassium has 
also had as an objed the solving bv its means the problem 
of ascertaining if it is really possible to procure a chloride 
of potassium which does not give, under any circumstances, 
any indication of the presence of sodium, and of obtaining 
this compound in such a state of purity, that the result 
arrived at in determining its atomic weight in regard to 
that of silver would leave no doubt in anybody's mind. 

My investigations have included the compounds of 
potassium, sodium, thallium, lithium, calcium, strontium, 
and barium. 

I have borne in mind the fad that the results depend as 
much on the medium in which the metallic compounds 
are enclosed, as on their accidental impurities. 

This medium being, for example, air, I have found or I 
have not found sodium, according as the air gives or does 
not ffive indications of the presence of this metal. This 
U6t has led me to examine the air by means of the 
speAroscope. 

Respecting the Characteristics Impressed bf the Sur- 
rounding Air on Hydrogen Flames^ Illuminating Oas, 
Hvdrogen Blowpipe Flame f Oxy 'hydrogen Blowpipe 
Flame, Oxy-carho'hydrogen Blowpipe Flame, and 
Ordinary Flame, and on the Electric Discharge and 
Electric Arc, 

I must commence my statement with the observations 
which I have made on air. 

What I am about to say relates exclusively to the air 
of Brussels, to that in the " Mus^e de I'lndustrie,*' where 
I have worked, and in my own laboratory. Amongst the 
observations which I have to mention are many familiar 
to chemists engaged in speArum analysis ; but I must re- 
capitulate them in order to make my statement as com- 
plete as possible. 

The room in the Mus^ de l*Industrie in which I have 
earned on my spedroscopic researches measures about 
Z143 cubic metres. It can be made into a dark room, as 
I have had occasion to do daily during my researches. 

During the time occupied by my work the room was 
placed entirely at my disposal. 

When the external air is quiescent, and has been for 
several days saturated with moisture, a state of things 
which occurs in Brussels from the end of Odober to the 
middle of December, and the room, previously washed out 
with a copious supply of water, and properly ventilated 



from the external saturated atmosphere, has been kept 
closed for twelve or eighteen hours, a time necessary for the 
deposition of particles of dust, mineral matters, ftc, the jet 
of gas, mingled with a suitable supply of air, issuing from 
a well made Bunsen burner, terminated by a pipe of 
platinum, silver, or gold, free from sodium, or even a pipe 
of brass, well cleansed inside and out, burns with a flame 
of pure rich blue, in which it is impossible to deteA the 
presence of sodium bv any spedroscope. Let one then 
make a prismatic analysis of the top, middle, and baue of 
the lummous cone, the diameter of which varies from z to 
i\ cm. and the height from 10 to 25 cm. 

If one introduces, by means of a loop of fine platinum 
wire, into the middle of the height of the flame, some 
dilute hydrochloric acid or some pure chloride of ammo- 
nium, the colour of the upper half changes immediately ; it 
turns green, and the intensity of the colour varies in pro- 
portion to the quantity of hydrochloric acid or chloride 
of ammonium introduced. In the flame thus rendered 
visible, it is impossible to recognise by prismatic analysis 
the slightest trace of the spedrum of sodium, or of a par- 
tially burnt hydrocarbon. 

Having substituted for the Bunsen burner a blowpipe 
of platinum or silver, previously cleansed from all sodium 

g articles, and for the illuminating gas properly purified 
ydrogen, one notices that this gas burns in pure air with 
a flame so colourless, and with such a faint luminosity, 
that in the dark the eye can scarcely perceive it. One 
cannot discern in any part of this flame the slightest indi- 
cation of the sodium ** D *' line, or of a continuous spec- 
trum. 

The introdudion of hydrochloric acid or of pure am* 
monia into hydrogen burning in pure air, gives direAly to 
its colourless flame a tint of a livid greenish yellow, similar 
to that seen when burning hydrogen in chlorine. The 
prismatic analysis of this flame does not enable one to 
deted the presence of the sodium line or of a continuous 
spedrum. 

In the blowpipe, with a pipe of pure platinum, cleansed 
inside and out from sodium particles, fed with a mixture 
in proper proportions of illuminating gas, or of hydrogen 
and air, or of pure hydrogen and oxygen, spedroscopic 
observation demonstrates in all cases the complete 
absence of the sodium *' D ** line, whatever may be the 
part of the flame examined. After the introdudion of 
hydrochloric acid, which greatly alters the colour of these 
flamesi one can find no trace of the sodium line. 

To complete these proofs, I must adkl that, in the 
darkened room, with pure air, spedrum analysis does not 
enable one to deted the appearance of any spedrum, not 
even a glimmer from the upper two-thirds of a flame from 
a well made Bunsen burner,* terminated by a platinum 
tube, or from a flame of from zo to 25 cm. length issuing 
from a platinum blowpipe supplied with air or with pore 
oxygen. 

The spedrum only appears from this part of the flame 
or blowpipe flame when one puts there a solid non-vola- 
tile body, and in this case the spedrum produced is con- 
tinuous, as we know. 

As regards the blowpipe flame which restUts from the 
combustion of an excess of pure hydrogen in equally pure 
oxygen issuing under pressure from a platinum burner, 
frequent observations permit me to state that, in the 
portions of this flame where the temperature is not high 

* Wheo the barner it faultily made, as ia often the caae, the flame, 
instead of GontittinK ot a singU cone aurrounded by a barely viaiblo 
but very hot envelope, reaolvea itaelf into two conea, exteodinf from 
the bate almott to the apex ; an internal cone, tltghtty luminoua and 
purpltt aurmounted by a aecond cone of purt blue in pure air, aur- 
rounded again by a barely vltible envelope where the combuttion of 
caibon takea place* In the flame from thia badly-made burner, tha 
second cone agreea with the conditiona mentioned above ; that ia, 
in the abtence of any ape^mm, although the intide cooe gtvca to 
apeftrum analyait the partial tpeArum of burning hydrocarbona. to 
which I aha 11 return later on. Whichtvtr was tnt bumtr luctl, / 
hawe always placed in tkt barely visible external envelope o/tkeJUme 
the body wkuh I wished to put im it for the pmfou oj avaAtiir a sPeC' 
tmm analysis. 



J 



CVSIMCUi MBVM^ I 

oa. ii» 189s. I 



Report of Committee on Atomic Weights. 



179 



enough to brioe the platinnm well ap to melting-point, 
speAnim aoelytis does not enable me to see a spednim. 
The place of the speAram is occupied entirely by a dark 
band, even when the width of the slit in the collimator of 
the spearoicope eaceeds the limit necessary for distina 
▼ision of the dark lines in the solar spedrum. As soon 
aa the temperature of the flame reaches the fusing-point 
of platinnm, the hydrogen becomes incandescent; its 
colour becomea a pale or sky blue. Spedrum analysis 
then shows the appearance of a continuous spedtrum, yet 
without the formation of bands or lines. It resembles 
that from the upper third of a blowpipe flame in which 
the hydrogen has not reached the point of incandescence. 
As a matter of fad, the flame which issues from an oxy- 
hydrogen burner under more or less pressure, is composed 
of two cones superposed, as in the case of a badly made 
Bunsen burner, of a lower internal cone coloured light 
blue in pure air, merging into the upper colourless cone, 
when it consists of the oxyhydrogen flame fed with an 
excess of hydrogen and oxygen. 

Spednim analysis of this lower internal cone gives 
a continaous spedrum, destitute of bands or lines, and 
whose brightness increases continuously from the point 
np to the part where the temperature is at a maximum 
and ID a condition to keep iridium and rhodium fused. I 
shall return later on to the subjed. 

On substituting for the hydrogen some illuminating gas 
or a very volatile hydrocarbon, — for instance, petroleum 
naphtha or similar body in the state of vapour, issuing 
from a platinnm burner,— one notices analogous fads as 
regards the lower cone, which is always coloured blue. 
The ipedrum analysis of this cone allows one to see a 
continuous spedrum crossed with bands and lines of ex- 
ceeding brilliance. The bands and lines are numerous. 
Towards the portion of the lower cone, where the light of 
the spedrum is most dassling, the temperature is so high 
that rhodium and iridium can be kept fused. I shall re- 
turn to this spedrum later on. 

To resume — If one makes a prismatic analysis of that 
part of the blowpipe flame of hydrogen and air, of 
oxyhydrogen, or of oxy hydrocarbon, in which platinum 
begins to melt or in which it is quite melted, or in which 
iridium can be kept in a state of fusion, whether there 
be either no spedrum or one of great brilliance ; in any 
case the spedrum analysis does not enable one to deted 
the presence of the sodium D line, when the air in which 
the experiment takes place is pure, or at least has a given 
relative degree of purity ; when the elements used 
to produce the flame are pure; and, lastly, when the 
apparatus itself yields no trace of sodium. 

I ihall certainly not surprise those who have done any 
■pedrum analysis when I say that I have met with the 
greatest diflBcnlties in verifying, under the conditions 
given, the fads written above, simple as they seem. 
(To be continaed). 



REPORT OF COMMITTEE ON ATOMIC 

WEIGHTS, PUBLISHED DURING i894-* 

By F. W. CLARKE. 

(Coodaded from p. 167). 

Thallium. 
Two determinations of atomic weight were made by 
Wells and Penfield to ascertain the constancy of the 
element as such {Am. Journ. Sci., 3, xlvii , 466). The 
nitrate was fradionaily crystallised until about z.2oth 
remained in the mother-liquor, while another twentieth 
had been subjeded to repeated re-crystallisation. Both 
fradions were converted into thallium chloride, which 
was dried at Ioo^ and in both the chlorine was estimated 

• From the %mmal of the Ammam Chmical Society, vol. xvii.» 
No. 3 . Read at the Boston BlevtinK, Dec. a8, 1894. 



by weighing as silver chloride 00 a Gooch fiktr. The 
results were as follows : — 

TlCl. AfQ. At.wt.TL 

Crystals .. •• 3*9146 S3393 304*47 
Mother-liquor •• 3*3415 X'9968 904*47 
Calculated with Ag= 107*92 and Cla35-45. 

In the report for 1893 Lepierre'i work 00 thalHom was 
given, and the last value cited was T1b203*oOy varying 
widely from the rest of the series and affeding the laean. 
The mean stated by Lepierre was 103*62, and as found 
by me was 203*57. Lepierre {BulL Soc. Ckim^ 3, m^ 
423) now calls attention to the fad that his value 203*00 
was a misprint for 203*60, and that his mean was there- 
fore corredly given. He also gives additional detaila 
relative to his work. 

Bismuth. 
The long- standing controversy between Schneider and 
Classen over the atomic weight of bismuth has led to a 
new set of determinations on the part of Schneider (^buni. 
Praki. Chim,, 2, 1., 461). The old method was still used ; 
namely, of converting the metal into the trioxide by means 
of nitric acid and subsequent ignition of the nitrate ; but 
the metal itself was carefully purified. Results aa fol* 
lows:— 

Wt. Bi. • Wt. Bi,0,. P.c. Bl in BisO.. 

5*0092 5*5868 89*661 

3*6779 4*1016 89*648 

7*2493 80854 89659 

9*2470 10*3x42 89*662 

6*0945 67979 89653 

12*1588 13*5610 89*660 



Mean 



89*657 



If Oa i6« Bi ranges from 207*94 ^o 3o8*X5, or id mean 
208*05, confirming the earlier determinations. 

Tin. 
Incidentally to his paper on the white tin sulphide 
Schmidt gives one determination of the atomic weight of 
the metal [Btr.d, Chsm. Ois,, xxvii., 2743). 

6659 SnOa. Hence Sd« 1x8*48. 



0*5243 grm. Sn gave o'( 



Anomalous Nitroobn. 
An important discovery has been made by Lord Rav« 
leigh, who finds that nitrogen obtained by purely 
chemical methods is perceptibly lighter than that from 
atmospheric air (Chbm. Nbwb, Ixix., 231, May 18, 1894). 
Equal volumes of the gas, variously prepared, weighed as 
follows :— 

By passing NO over hot iron 2*30008 

•> N.O „ 2*29904 

„ AmNOa ,1 2*29869 

For nitrogen from air he found:— 

From air passed over hot iron 2 '3 1003 

„ „ through moist FeOaHa 2*31020 
„ „ over hot copper ,. •• 2*3x026 

Investigating the cause of this anomaly, with the co- 
operation of Ramsay, Kayleigh came to the astonishing 
results communicated a few months later to the British 
Association. It was found, in short, that atmospheric 
air contains a gas heavier than nitrogen, and hitherto 
unknown. Its density, in a sample as pure as could be 
obtained, was X9'09, and it was charaderised by extraor- 
dinary inertness. Whether it is a new element, or allo- 
tropic nitrogen, Nj, remains to be determined. The 
work is cited here because it shows that the density of 
nitrogen as hitherto determined can give no trustworthy 
value for the atomic weight of the element. 

Miscellaneous Notes. 
Some data bearing upon the atomic weight of tellurium 
are given by Gooch and Howland (Am, y. Sei, [3], 



i8o 



Lecture Apparatus. 



fOauficALNnrtf 
I Oft. iz, 1805. 



slvii^M 375)* At the homogeneity of teUorimn it ttill 
uncertain, I omit their details. 

Wanklyn's attempt to show that the atomic weight of 
carbon is not 12, bat 6, was noted last year. He has 
since published more on the subjed in a paper on Russian 
Kerosene {Phil. Mag,, [5], xjucvii., 495), and the matter 
was also discnssed at the Oxford meeting of the British 
Association (Chbm. News, Ixx., 87, Aug. 24, 1894). 

In a communication apon the Stasian determinations 
(CompU Rgnd., cxviit., 528), Hinrichs discusses the avail- 
ability of silver as a secondary standard in the scale of 
atomic weights. He makes silver, chlorine, bromine, 
iodine, and sulphur all Prontian in value. Hinrichs also 
has published his views upon atomic weights in ixtinso 
in book form (** The True Atomic Weight of the Che- 
mical Elements, and the Unity of Matter," by Quttavus 
Detlef Hinrichs, St. Louis, 1894). 

In conclusion I submit a table of atomic weights re- 
vised to January x, 1894. O-16 is still retained as the 
base of the system ; but I hope that in another year it 
will be prafticable to return to H "• x. 

Name. Atomic wsifht. 

Aluminium •• •• •• •• 27* 

Antimony • .. •• lao* 

Arsenic •• •• • 75* 

Barium •• •• •• •• •• X37'43 

Bismuth 208* 

Boron •• •• •• •• •• xx* 

Bromine •• •• •• •• •• 79*95 

Cadmium • xxa* 

CsBsium • •• •• 132*9 

Calcium •• •• 40* 

Carbon xa* 

Cerium •• •• • X4o*a 

Chlorine 35*45 

Chromium* • •• •* •• •• 52*x 

Cobalt 59*5 

Columbium •• •* •• •• 94* 

Copper 63*6 

Erbium x66*3 

Fluorine •• • •• X9* 

Gadolinium •• X56*x 

Gallium •• •• •• •• •• 69* 

Germanium •• •• •• •• ^^'l 

Glucinum.. • *• 9' 

Gold 197*3 

Hydrogen x*oo8 

Indium • •• 1x37 

Iodine .. •• • X26*85 

Iridium •• •• •• •• •• X93*x 

Iron 56* 

Lanthanum •• •• •• •• X38*2 

Lead 206-95 

Lithium •• •• •• •• •• 7*02 

Magnesium 24*3 

Manganese •• •• •• •• 55* 

Mercury •• •• •• •• •• 200* 

Molybdenum •• •• •• •• 96* 

Neodymium •• .. •• *• 140*5 

Nickel 5S7 

Nitrogen «• .. 14*03 

Osmium •• •• •• •• •• X90*8 

Oxygen •• •• •• •• •• x6' 

Palladium.. .. •• .. •• xo6*5 

Phosphorus .. • 3X* 

Platinum •. •• X95* 

Potassium •• 39'XX 

Praseodymium •• •• •• X43*5 

Rhodium X03* 

Rubidium 85*5 

Ruthenium xoi*6 

Samarium • •• 150* 

Scandium • • • • 44* 

Selenium • •• •• 79* 

Silicon • •• •• 284 



Name. Atomic wdght. 

Silver •• •• •• •• •• 107*92 

Sodium •• •• •• •• «• 23*05 

Strontium •• •• •• •• 87-66 

Sulphur .. •• • 32*06 

Tantalum 182*6 

Tellurium. • X25* 

Terbium •• x6o* 

Thallium •. •• 204*18 

Thorium • • 232-6 

Thulium 170*7 

Tin X19* 

Tjtanium 48* 

Tungsten •• •• •• .. •• x84*9 

Uranium .. .. •• •• •• 239-6 

Vanadium. • •• •• •• •• 51*4 

Ytterbium.. .. •• .. .. X73* 

Yttrium • •• 89*1 

Zinc 65*3 

Zirconium 90*6 



LECTURE APPARATUS. 
By Dr. W. R. HODQKINSON, F.R.S.B. 

In the AnnaUn d$f Chime (vol. cdxxxiv., p. 3) Volhard 
describes an apparatus for certain ledure purposes. I 
have had an apparatus of very similar form and for the 
same purposes in use in my le^ures at the Royal Military 
Academy for the past eight years or more. 




One or two additions or improvements were added some 
time ago by my assistant, Mr. J. Young, A.R.C.S. 



CanpcAL Mbwb* I 
oa. XI, iSgs* I 



Constituents of the Gas in Cleveite. 



i8i 



The tabflUoce to be barnt can be fired by the eledric 
wires; the particalar form of gaage obviates any danger 
of gases escaping owing to eacesstve expansion at the 
moment of horning. It is, as will be seen, only a large 
distilling flask with a stopcock sealed on the tube. Oxy- 
gen may be driven in and through by means of the two 
taps, i^Ur the sabstaoce has been put in the cup. This 
is an advantage generally. 

As a rule the rubber stopper is wired down and mercury 
nsed in the gauge. 

The apparatus can be used in a rough quantitative way. 

Koyal Military College, Woolwich. 



ON THB 

CONSTITUENTS OF THE GAS IN CLEVEITE. 

Br C. RUNGS and F. PASCHEN. 

Wb have invettisated the spe^rum of the gas discovered 
in the mineral cleveite li^ Ramsay, and have found it to 
be most regular. It consists of six series of lines, the in* 
tensity of the lines in each series decreasing with 
d^reasing wave-lengths. Similar series of lines have 
been obs^ed in many spe^a. The first series was dis- 
covered by Dr. Huggins in the ultra-violet spedra of a 
number of stars. It proved to belong to hydrogen, and to 
be the continuation of the four strong hydrogen lines in 
the visible part of the speArum. Johnstone Stoney had 
already shown that three of the wave-lengths of the 
visible hydrogen lines were most accurately proportional 
to the values g/5, 4/3, 9/8, when Balmer discovered that 
these Taloes were given by the formula— 

for M >■ 3, 4, 6, and that the other wave-lengths of the 
•eries were proportional to the values obtained by substi- 
ting for m tne other entire numbers greater than three. 
The series has now been followed from m*3 tomB2o, 
the lines growing weaker and weaker to the more refran- 
jjgble aide, and approaching each other closer and closer. 
The fonnola shows that they approach a definite limit for 
large Yalaes of m. This is seen more clearly when 
we consider wave-numbers instead of wave-lengths, which 
according to the formula would be proportional to— 

m 

Many series of lines similar to the hydrogen series 
were discovered by Liveing and Dewar. They have 
called them harmonic series, and have compared them to 
the series of over-tones of a vibrating body. They have 
been further studied by Rydberg and by Kayser and 
Rnoge. We cannot here enter into any detailed account. 
We only want to explain so much as to make the 
cooclnsions understood which we have drawn from the 
mAram of the ^as in cleveite. The wave-lengths X of 
the lines beloogmg to the same series are always ap- 
proximately conneaed by a formula somewhat similar to 
bnlmer's— 

x/X«A-B/iM*-C/m«. 
A determines the end of the series towards which the 
fines approach for high values of m, but does not influence 
the dinerence of wave-numbers of any two lines. B has 
■early the same value for all the series observed, and C 
ougr be said to determine the spread of the series, 
oorresponding intervals between the wave-numbers being 
larger for larger values of C. As B is approximately 
known, two wave-lengths of a series suflBce to determine 
the constants A and C, and thus to calculate approxi- 
mately the wave-lengths of the other lines. It was by 
this means that we succeeded in disentangling the spec- 
tmm of the gas in diveite, and showing its regularity. 



In the spedrum of manv elements two series hava 
been observed for which A has the same valoe, so that 
they both approach to the same limit. In all these cases 
the series for which C has the smaller value, that is to say 
which has the smaller spread, is the stronger of the two. 
In the spedrum of the gas in cl^eite we have two in- 
stances of the same occurrence. One of the two pairs 
of series, the one to which the strong yellow double line 
belongs, consists throughout of double lines whose wave* 
numbers seem to have the same difference, while the lines 
of the other pair of series appear to be all single. Lithium 
is an instance of a pair of series of single lines approach- 
ing to the same limit. But there are also many instances 
of two series of double lines of equal difference of wave- 
numbers ending at the same place as sodium, potassinm* 
aluminium, &c. There are also cases where the members 
of each series consist of triplets of the same difference of 
wave-numbers as in the spednim of magnesium, calcium, 
strontium, sine, cadmium, mercury. But there is no in- 
stance of an element whose spedrum contains two pairs 
of series ending at the same place. This suggested to ns 
the idea that the two pairs of series belonged to different 
elements. One of the two pairs being hv far the stronger, 
we assume that the stronger one of tne two remaining 
series belongs to the ssme element as the stronger pair. 
We thus get two spedra consisting of three series each, 
two series ending at the same place, and the third leaping 
over the first two in large bounds and ending in the more 
refrangible part of the spedrum. This third series we 
suppose to he analogous to the so-cslled principal series 
in the spedra of the alkalis, which show the same 
features. It is not impossible, one may even say not un» 
likely, that there are principal series in the spe€tra of the 
other elements. But so far they have not been shown to 
exist. 

Esch of our two spedra now shows a close analogy to 
the spedra of the alkalis. 

We therefore believe the gas in cllveite to consist of 
two, and not more than two, constttnents. We propose 
to call only one of the constituents helium, the one to 
which the bright yellow double line belongs, whose 
spedrum altogether is the stronger one, while the ether 
constituent ought to receive a new name. 

We have confirmed this rather hypothetical condosioa 
by the following experiment :— The connexion leading 
from our supply of cfeveite gas to the vacuum tube con* 
tained a side branch parting from it and joining it again. 
There were stopcocks on either side of the side branch, 
and a third one in the side branch. In the main tube be- 
tween the ends of the side branch a plug of asbestos was 
tightly inserted. To prepare the vacuum tube only the 
tap leading to the supply wss closed, the whole space np 
to this tap beins carefully evacuated. Now the side 
branch was closed, end the tap leading to the supply was 
opened. Then we observed that the liaht of the eledric 
discharge in the vacuum tube was at first greenish, and 
after a while grew yellow. By cutting off the current of 
gas after a suflSciently short time, we succeeded in 
making a vacuum tube which remained ereenish. On 
examining it in a small spedtroscope with which we could 
overlook the whole spedmm, we found that the intensi- 
ties of the lines had changed. The yellow line was 
scarcely as bright as the green line 5016, and the red line 
7065 had apparently decreased relatively to 728a and 
6678, although it was still stronger than 7282. The two 
lines that had decreased in intensity belong to the 
second set of series, while the others are meml^rs of the 
first set The other visual lines of the second set could 
not very well be examined, because they are more in the 
violet part. 

This observation confirms our speAroscopic result. The 
gas in cleveite may be taken to be a mixture of two gases 
of different density, of which the lighter one is more 
rapidly transmitted through the plug of asbestos. There 
is, however, the objedion to be raised, that in the green 
tube the pfessora is less, and that the difference of inteo- 



l82 



Vapour-tensions of Mixtures of Volatile Liquids. 



* CBBIilCAL NbWS, 

1 Oft. II, 1895. 



•hies is due to the presBore being different. This mast 
be further inquired into. 

We were not satisfied with the visuaJ observation of 
the change of intensities in our green tube, but thought 
it desirable to test the conclusion by the bolometric 
OBeasorement of the two lines that we have discovered 
in the ultra-red part of the spe^rum. If we were right, 
the ultra-red line of smaller wave-length, which belongs 
to the second set of series, ought to have decreased in 
intensity relatively to the other ultra-red line. This we 
foond to be so indeed. In the yellow tubes the intensity 
of the smaller wave-length was to that of the other on an 
average as 3 to x, while in the green tubes it was as 1*8 
to I. This confirmation we consider the more valuable as 
it does not depend on any estimation which may be biassed 
by the personal opinion of the observer, but is based on 
an obje&ive numerical determination. 

Another confirmation may be gathered from the spec- 
trum of the sun*s limb and that of several stars. Let us 
confine our attention to the six strongest lines in the 
visible part of the spedrum : — 

7066, 6678, 5876, 5016, 4922, 4472. 

The first, third, and sixth belong to the second set of 
series ; the second, fourth, and fifth to the first set. These 
six lines have all been observed in the spedrum of the 
8un*s limb, as Norman Lockyer and Deslandres have 
pointed out. Now, according to their appearance in the 
speArum of the sun's limb, they may be classed in two 

groups, one group being always present, the other group 
eing sometimes present. C. A. Young long ago called 
attention to the difference in the frequency of appearance 
of the chromospheric lines. He has given them fre- 
quency numbers, roughly estimating the percentage of 
frequency with which the lines were seen during the six 
weeks of observation at Sherman in the summer of 2872. 
According to Young, 7066, 5876, 4472 have the frequency 
number xoo, while 6678, 5016, 4922 have the numbers 25, 
30, 30, showing that one of the two constituents w^ 
always present, while the other was only seen about once 
in every four cases. 

The lines of both constituents have been observed in 
the speftra of a considerable number of stars, fi, i, t, C 
y Ononis, a Virginis, $ Persei, $ Tauri, ri Urss majoris, 
/3 Ly rs. In the spedrum of fi Ly rse thirteen lines have been 
identified with certainty. But the most interesting case 
in point is the spedrum of Nova Anrigse, that wonderful 
star whose sudden appearance was announced to astrono- 
mers in 1892 by an anonymous post card. In the spec- 
trum of Nova Aurigs the two lines 50x6 and 4922 were 
very strong, while 4472 was weak, and 5876 has only 
been seen by Dr. Huggins, we believe only on one occa- 
sion, and appears to have been very weak. Now 50x6 
and 4922 belong to the lighter constituent, and are to- 
gether with 6678 the strongest lines in the visible part of 
the spearum ; while 5876 and 4472 are the strongest lines 
of the other constituent in the visible part of the spec- 
trum. In Nova Aurigs, therefore, the lighter constituent 
gave a much brighter speArum than helium proper. But 
there may here be raised an objedion, which indeed we 
do no not know how to refute. Why has the line 6678 
not been observed ? It is a pity that the red part of the 
speftrum cannot be more easily photpgraphed. Nova 
Anrigs has now become very weak, and besides the spec- 
trum is quite altered, so that we shall never know 
whether the red line 6678 was really absent or has only 
escaped notice. 

From the faa that the second set of series is on the 
whole situated more to the refrangible part of the spec- 
trum, one may, independently of the diffusion experi- 
ment, conclude that the element corresponding to the 
second set is the heavier of the two. In the spedra of 
chemically related elements like Li, Na, K, Rb, Cs, or 
Mg, Ca, Sr, or Zn, Cd, Hg, the series shift to the less 
refrangible side with increasing atomic weight. But it 
appears that in the spedra of elements following each 



other in the order of their atomic weights in a row of the 
periodic system like — 

Na,Mg,Al; 
K.Ca; 
Cu, Zn ; 
Rb, Sr; 
Ag, Cd, In ; 

the series shift the opposite way, so that the spedrum of 
the element of greater atomic weight is as a whole 
situated further to the more refrangible side. Now in 
our case the density of the gas has been determined by 
Langlet f published by Clhvt) and by Ramsay to be about 
double the density of hydrogen. Assuming the atomic 
weights of the two constituents to be between that of 
lithium and that of hydrogen, they would both belong to 
the same row of the periodic system, and therefore the 
more refrangible set of series would correspond to the 
greater atomic weight. 

For convenience of reference all the observed lines are 
given in the following table, the wave-lengths being 
abridged to tenth-metres. 

Lightif Con$titutnt, 

First Second 

Priadpal series* sobordiDsta series, sabordioatc series. 

20400 6678 728a 

50x6 4922 5048 

3965 4388 4438 

36x4 4x44 4x69 

3448 4009 4024 

3355 3927 3936 

3297 387a 3878 

3258 3834 3838 

3231 3806 3808 

3a «3 3785 

Htavitr ConsHtuint (HtUum propn). 



3889 
3x88 

2945 
2829 
2764 
2723 
2696 
2677 



Double lines. 


DoQble Hoes. 


5876 


7066 


447a 


4713 


4026 


4X2X 


3820 


3868 


3705 


3733 


3634 


365a 


3587 


3599 


3555 


3563 


353 « 


3537 


3513 


35x7 


3499 


3503 


3488 


3491 


3479 


3482 


3472 




3466 




3461 





--Natun, September 26, 1895. 



ON THE VAPOUR-TENSIONS OF MIXTURES 
OF VOLATILE LIQUIDS.' 

By C. E. LINBBARQBR. 
(OoDtinaed from p. 170). 

Ca!culaiion o/Risuiis^ 
In the calculations it is assumed that the laws of perfeA 
or ideal gases may be applied to the mixtures of vapours ; 
that is, the laws of Boyle, Gay^Lussac, and Dalton. 
Where not too much vapour is present in the gaseous 
mixture the legitimacy of this assumption is unquestion- 
able ; and even though this condition be not fulfilled, the 



* Abridged from the Joutnal of the American Ch^icat Socistf 
vol. xvii.. No. 8, Aogust, 1895. 



^Sa^, SS^*' } Vapour-tensions of Mixtures of Volatile Liquids. 

Tablb \.^Vapouf-Unsion$ of Pure Liquids, 

LoM Volomo of Volume Internal Bare- Tentioo of 
Name of liqiiid. Temperatore. io loaa of air preetore meter io vapour in 

tftma. in c.c. in cc. in m.m. m.m. m.m. Hg. 
Hg. Mg. 

Bemene 34*8'* 1*3805 443* 1876 5 760 145-4 

Monocblorobensene 34*8^ o'^igi 51 1883 xo 757 203 

Monobrombenzene 34*8** oi28g 20 1888 xo 757 8-o 

Toluene 34*8'* 0-2451 67-6 1014 xi 754 468 

34'8'' 0-4672 128-9 1949 XI 754 467 

MeUzjlene (not especially purified) .. 34-8<' o«xo8o 258 x2ox 17 757 4x7 

„ .• •. 34-8° 0-X085 25-9 X20X X7 758 4x8 

Nitrobenxene 34*8** 00090 1-85 x2io 23 757 xx6 

„ 34-8*^ 00088 x-83 X207 2X 757 X-X5 

Carbon tetrachloride 34*8** 33803 555 1913 20 758 169-4 

„ „ 27-8** 2-403X 3-96 X908 18 756 1300 

Chloroform 350** 3*0320 6448 X033 25 755 29o-x 

Ethyl iodide 34 '8** 4*209X 683- X913 20 756 X99-0 

27-8'' 2-9760 483- X918 22 756 X52-2 

Carbon bisulphide 20-o<» 2-454X 7774 X2o6 2x 756 2964 

Methyl formate 20-o«> 51000 X95'8 XX96 x6 756 469-4 

Acetic acid 35*0^ o'^goo 700 X960 20 760 263 

NoTB.^Y) » Young, Chem. Sec., Iv., 486, X889 ; (R) » Regnault, Mhmoifis d$ VAcadimUt xxvi., 
(R ft Y) B Ramsay and Young, Chtm, Soc, xlix., 790, x886. 



183 



Tfloaion acoord* 

inf to other 

ooeenrers. 



X47-2 

20*0 

8-0 



G9 



172-6 


(R) 


X30-8 


(Ri 


30X-X 


<*^!> 


206*0 


|Ri 


1547 


(RJ 


298' X 


(R) 


26-5 (R&Y) 


239, 1862; 





approximation to accuracy may be sufficient (see '* Com* 
parison of the Vapour-teosions," ftc.)» 

Calculation of Volum$ of Air passid through a Mixtun. 
— In order to force the air in the measuring vessel through 
the liquid in the absorption-vessel, it is necessary that it 
be brought under a pressure equal to that of the atmo* 
sphere plus that required to vertically displace the liquid 
contained in the bulbs, the latter pressure varying with 
the denaity and amount of the mixture. The volume of 
the air under atmospheric pressure may be obtained then 
aa follows : — 

Let P represent the pressure of the atmosphere. Let 
P* represeut the pressure which forces the air through the 
liquid. Let V represent the volume of air under the 
presaore P+ P'. Let V represent the volume of air imder 
the pressure P. 

According to Boyle's law, and inasmuch as the tem- 
perature remains constant, — 

P 

CakultUion of Composition of Mixtun of Liquid Vapot' 
is$d, — As this calculation is simply one of quantitative 
analysis, it is not necessary to treat of its details. 

Calculation of Partial Volumis of Mixtuns of Vapours, 
— Let m represent the quantity of one component in the 
saseous mixture. Let M represent its molecular mass. 
Let 22*32 represent the volume in litres of a grm.-molecule 
of hydrogen at the temperature o^ and under the pressure 
760 m.m. Let a represent the coefficient of expansion. 
Let vi represent the volume of vapour at the temperature 
of the determination, ^ and under the atmospheric pres- 
sure, p. We then have — 

760 (X -fttf) 

P 

Calculations of Partial Prtssuns of Components of 
Vapour Mixtun, — Let Vx represent partial volume of one 
component. Let Va represent partial volume of the other. 
Let 9 represent partial volume of air. Let /x represent 
partial pressure of one component. Let pa represent par- 
tial pressure of the other. Let p represent the atmo- 
spheric pressure. 

In accordance with Dalton*s law, — 



vi « 22-32 -- X 



Pi 'P 



Vi 



and^ 



{V + Vi+ Vz) 



Pt-'p 



Vi 



(• + »! + »a) 



Comparison of the Vapour'tensions obtained by the Method 

herein Described and those obtained by other Methods. 

Probably the best way to judge of the accuracy of the 
results obtained in the determination of the vapour*ten- 
sions of liquids according to the method described in thia 
paper is to compare them with the results obtained by 
other investigators working by other methods. Also a 
criterion of accuracy is to k^ found in the more or lets 
close concordance of duplicate experiments. In Table L 
are given the necessary data of my experiments to- 
gether with the results obtained by others. It was in 
some cases necessary to interpolate the results of others 
inasmuch as my results referred to a limited number of 
temperatures; the interpolations were made on a large 
scale, so as to avoid any slight inaccuracy. The original 
papers of Young and Regnault I am now unable to con* 
suit, and have to take their data as given in Landolt and 
Bdrnstein*s '* Physikalische * Chemische Tabellen" or 
other reprodudions. 

An inspedioo of the table shows a most excellent cor* 
respondence between my determinations of vapour-ten* 
sions and those of others, when the liouid is but slightly 
volatile, as in the case of the halogen substitution-produds 
of benxene. But when, at the temperature taken for a 
determination, the elastic force of the vapour exceeds xoo 
m.m. of mercury, the correspondence becomes less close ; 
and it is at once seen from the data that the greater the 
volatility of a liquid, the greater the discrepancy. Let ns 
take carbon tetrachloride and ethyl iodide for examples, 
since determinations of their vapour-tensions were carried 
out at two different temperatures. For carbon tetra- 
chloride the difference between Regnault's results and 
mine is 3^ m.m. of mercurv at 34*8° and ^g m.m. of 
mercury at 27*8*^; for ethyl iodide, the difference at 
34*8° is 7^0 m m. oSr mercury, and at 27*8* x/g m.m. of 
mercury. Other examples point to the same result. 

The cause of this want of concordance between my 
results and those made by other methods has been hinted 
at in a discussion of the errors to which this method is 
subjed. The assumption, made in the calculations, that 
the vaporous mixture may be treated as a mixture of 
ideal gases, cannot be maintained when the volume of 
the vaporised liquid forms more than a small fradion of 
the total volume of the gaseous mixture that leaves the 
absorption vessel. The vapour of ethyl iodide that was 
carried off by the air, occupied more than a fourth of the 
total volume, and the other volatile liquids also occupied 
relatively lar^e volumes ; the volumes of the vapours of 
the less volatile liquids, however, were but a small part 
of the volume of the air pasted through the liquid. And, 



\ 



I Si] 



Analytical Chemistry. 



t OlIKMICAL HBWB, 

I oa. XI, 1805. 



M has been shown, the less volatile liquids give results 
perfedly concordant with those obtained by others. 
Duplicate determinations of the vapour-tensions of some 
of the liquids, as toluene, nitrobenzene, &c., give almost 
identical results. 

It would not be difficult to apply a correAion taking 
into account the greater volatility of some of the liquids. 
This I have not, as yet, done, as in certain details I wish 
to alter the apparatus so as to obtain even more accurate 
results ; thus the use of mercury as the liquid for expel- 
ling the air from the measuring vessel would render the 
system of drying-tubes unnecessary ; also, ground-glass 
joints are undoubtedly preferable to rubber connexions. 
Although it is my intention to study and modify the ap- 
paratus further, I do not want to seem to ** reserve ** this 
subjed of investigation ; on the contrary, I would be 
most glad to see the apparatus tried and tested by others. 

Although the results obtained by the employment of 
this method do not have, in the case of the more volatile 
liquids, the same degree of accuracy attainable by other 
methods, still they are suited to the rec|uirements of an 
investigation of the vapour-tensions of mixtures of liquids, 
since both liquids, if their vapour-tensions be not too dif- 
ferent, are affeded alike by any weaknesses in the method, 
and the phenomenon observed permits of the drawing of 
theoretic conclusions. Yet I have been careful in the 
discussion of results to limit myself as much as possible 
to such as were of the same accuracy as results obtained 
by others ; thus, my method can be counted upon to give 
results accurate to less than z m.m. of mercury when the 
vapour- tension does not exceed xoo m.m. of mercury, and 
to less than 2 m.m. of mercury when the vapour-tension 
is less than 150 m.m. of mercury ; as can at once be seen 
by a comparison of the data due to Young {loc, cit) and 
Regnault (loc, cit.) in the greater number of cases a closer 
correspondence than to within 2 m.m. cannot be found. 
However, the conclusions which I draw from my experi- 
ments would still hold if the error in the determination 
were several times greater than that admitted above, in- 
asmuch as it affeas each liquid in the same way, so that, 
while it may affed the absolute accuracy, its relative tQe€t 
is but slight. 

(To be coDtioaed). 



NOTICES OF BOOKS. 



Analytical Chemistry. By N. Mbmschutkin, Professor 
in the University of St. Petersburg. Translated from 
the Third German Edition, under supervision of the 
Author, by James Locke. London and New York : 
Macmillan and Co. 1895. Svo., pp. 512. 
In noticing this work we must distinguish between the 
matter and the language. The author^s instruaions will 
be pronounced excellent by all competent chemists who 
may give them the necessary examination. We do not in- 
deed, see that the author proposes any novel reaaion or 
brings forward any new general method. But he lays due 
weight on the acquisition of the hMt of chemical thought, 
which he justly pronounces the most important objea of 
praaical work. Mere mechanical study he appraises at 
a very low value, considering that it cannot in a single 
instance teach how to make a correa analysis, to say 
nothing about developing the faculty of chemical thought. 
He condemns the praaice of allowing the student to enter 
upon analysis before he has been prepared by a thorough 
training in general chemistry. He insists that the neces- 
sary knowledge should be estimated not by the number 
of single and isolated faas with which he is familiar, but 
by the clearness with which he understands fundamental 
chemical phenomena and theories, — points not always 
duly appreciated by the routine examiner. 
, The work consists of two main parti, a qualitative and 



a quantitative. The author holds that the student should 
in the outset devote himself to the former branch alone. 

In a supplement to the seaion on qualitative analysis 
the author explains the use of the blowpipe, — which he 
remarks has almost completely disappeared from the la- 
boratory with the introduaion of the Bunsen gas-burner, 
though for the prospeaor and the traveller it retains all 
its former value, — of Bunsen's flame-readions, which are 
here very fully expounded, and of spearum analysis, 
which receives here an attention unusual in analytical 
manuals. 

Prof. Menschutkin describes the spedroscope of Bunsen 
and Kirchoff (not Kirschoffl), the reversal of the spec- 
trum, the dependence of the spearum upon the conditions 
of the experiment, the flame speara, the spark spedtra, 
the phosphorescence speara, and absorption speara. 

The recent results of Crookes, and of Kruss and 
Nilson, are mentioned, but with the remark that the 
subjea has not yet obtained the wide attention which it 
requires and merits. 

In the quantitative part of the work elearolytic deter- 
minations are mentioned somewhat briefly, with a recom- 
mendation of thermo-batteries, or of Meidinger and 
Bunsen elements. We find no reference to gas analysis, 
which is now of growing importance. 

The subjea-matter of this work is of unquestionable 
value, but the language employed is not incapable of 
amendment. Thus we find the term '* metalloids ** con- 
stantly used. The element which we commonly, in 
virtue of priority, name ** glucinium," is here termed 
*' beryllium,** and selenium and . tellurium are made to 
rank as metals. In the very first sentence of the book 
we read :~** the analytical branch of the science is given 
a sharply-defined position.*' ** Is given ** and kindred ex* 
pressions have come to be tolerated in newspaper para- 
graphs, but they are painful in a scientific treatise. 



Continuity of the Colligative Properties and the Polymer- 
isaiion of Matter through its Three Conditions, By 
JuLiEN Delaite. Brussels : F. Hayex. 1895. 
The author formulates the following law: — 

** The density of a mixture of several solutions, having 
no chemical aaion upon each other, is, if the temperature 
remains constant, the sum of the densities of the compo- 
nent solutions, if we refer their density to the total 
volume and accept as true the law of Boyle-Mariotte ap- 
plied to the dissolved salt.*' 

He gives a table of all the atomic volumes, showing 
that the condensation is inversely as the chemical aaivity 
of the elements. Potassium, sodium, calcium, bromine, 
all very aaive substances, have low atomic coefficients, 
whilst the heavy metals and carbon are most strongly 
condensed. Diamond is said to have the strongest con- 
densation, s 3271. 

Another table gives the ** integral weights ** of the ele- 
ments, not at all coincident with their atomic weights, 
and ranging from Hsz to Osa>2498**. Helium and argon 
do not appear to have come under the author*s investiga* 
tion. By combining the atomic coefficients and the inte- 
gral weights, Dr. Delaite arranges tbe elements in eight 
series. He remarks that though carbon possesses the 
highest atomic coefficient, yet its integral weight is rela- 
tively low, which partly explains the great aaivity of this 
substance in organic compounds. He believes that the 
chemistry yet to be constituted will be better entitled 
than that of Sterry Hunt to the title of a ** New Che- 
mical System.** 



A New Bactericide.— German medical and hygienic 
papers are now discussing a new badericide bearing the 
utterly misleading name of *' argonine." We hasten to 
inform our readers that this novelty is not a compound or 
derivative of argon, with which it has not the remotest 
conne^on. It is a compound of silver and caseine« 



y 



CHtUICAl NtWS, I 

OA. ir, 1895, r 



Chemtcal Noitces from Foreign Sources. 



185 



CHEMICAL NOTICES FROM FOHEIGN 
SOURCES. 



NoTS.— All degrees of temperature are Centigrade unless otherwise 
expressed. 

CompUs Rendus Hihdomadairei des Seances^ de V Academic 
<Us Sciences, Vol. cxxi., No. 13, September 23, 1895. 
Specimen of Black Ctrbon from Brazil. — Henri 
Moissan.— This carbon is a variety of black diamond 
which sometimes exhibits a confused crystallisation, and 
sometimes presents a shagreeny asped. M. des Cloixeau 
in his study on carbon has mentioned various crystals, 
among which is a complete cube with rounded edges. 
Such carbon is met chiefly in the province of Bahia and 
in small quantities in Borneo. It is much valued for 
tipping the crowns of boring apparatus. When of good 
quality its value is about 65 francs per carat. The sample 
which I have the honour of submitting to the Academy 
was found in the region between the Rio a Rancador and 
the brook das Bicas in the territory of the town of Len- 
goes. It weighs 630 grms. » 3073 carats, and is conse- 
quently the largest specimen which has been hitherto 
found. It is of a rounded form, distindly black. On ex- 
amination with a low microscopic power it has the appear- 
ance of a substance from which gases have escaped whilst 
in a pasty state. It is porous, and has lost about 19 grms. 
in weight since being taken out of the earth. The Bra- 
zilian miners have to pay to the owners of the lands on 
which they work a royalty of 25 per cent on the gross 
yield of stones and also a tax to the Government. 

Compotttion of Pelageiae. — Dr. A. B. Griffiths and 
C* Piatt. — The authors have determined the chemical 
composition of the violet pigment of the Medusa {Pelagia). 
The pigment and fatty substances are soluble in boiling 
alcohol and ether. The filtered solution is evaporated to 
dryness ; the residue is treated with a solution of soda, 
and the pigment rapidly extraded with carbon disulphide. 
On spontaneous evaporation the violet pigment is left as 
an amorphous residue. Of this pigment 0*2058 grm. 
yielded 0*47325 c.c. (?) of carbonic acid and 0081 of water. 
0*4605 of the pigment yield 15*15 c.c. of nitrogen at the 
barometric pressure of 742 m.m. and the temperature of 
I5^ The results answer to the formula CaoHi7N07. This 
pigment, which we name pelageine, is soluble in alcohol, 
ether, and acetic acid, insoluble in water, and very soluble 
in carbon disulphide. In an isolated state pelageine is 
bleached by light, and on spe(5lroscopic examination it 
does not show any charaderistic absorption-bands. 



Bulletin de la Societi Chimique de Paris, 
Series 3, Vols. xiii.>xiv.. No. 9, 1895. 

Thermic Study of the Anhydrous Barium and 
Strontium Iodides.— M. Tassily. 

Researches on the Combining-beats of Mercury 
with (other) Elements. — Raoul Varet. — A determina- 
tion of combining-heat of mercury with iodine (a +2^7 
cal.), bromine (» +40*7 cal.), oxygen (■■ +21*3 caL), 
and chlorine (» +49*8 cal.). 

Amorphous State of Melted Bodies.— C. Tanret.— 
Not all crystalline bodies re-crystallise on becoming solid 
after fusion^ Some remain amorphous; and many, which 
crystallise under ordinary conditions, become amorphous 
if cooled abruptly. Among those which are thus rendered 
amorphous after fusion, the author mentions the pent- 
acetines of glucose and the hexacetines of the adive 
inosites. 

Contribution to the Study of the Dissociation of 
A<5live Salts in Solution. — Ph. A. Guye and B. Rossi. 
. — This voluminous paper is not adapted for useful abstrac- 
ion, and does not merit insertion in extsnso. 



Calcium Phosphate in Milk.— L. Vandin. 

Isomeric States of Mercury Oxide.— Raool Varet. 

Volumetric Determination of Zinc. — L. Barche. — 
A reply to the criticisms of H. Lescoeur, who has operated 
upon a sample containing 13*9 per cent of impurities. 

Preparation of Ethylamine by the Redudtion of 
Ammonium Aldehydate. — Ferdinand Jean. — The 
author puts in a flask zo grms. ammonium aldehydate, 
recently prepared, along with a little water and ao grms. 
zinc powder. He then adds, in ten minutes, 150 grms. 
of hydrochloric acid (1:2), and after ten more minutes, 
30 grms. concentrated hydrochloric acid, moderating the 
readion by cooling the flask in a current of water. After 
forty* five minutes, it is heated for half an hour 00 the 
water bath. To obtain the ethylamine a large excess of 
soda is added so as to dissolve the zinc salt, and a violent 
current of steam is passed into the flask whilst heat is 
still applied. 

Adtion of the Primary Aromatic Amines on the 
Non-symmetric Ketonic Compounds. — L« Simon. — 
This memoir is not adapted for useful abstradion. 

Dimetbylamido-a-caprolc Acid. — E. Dunvillier.— 
Also not adapted for abstradion. 

Propionic Etbylhydantoine (Etbyluraminodopro- 
pane).— E. Dunvillier. — Ethylamidopropionic acid yield- 
ing merely a hydantoine and not the corresponding by- 
dantoic acid, and the amidic acids of the amines of the 
fatty series yielding merely a creatinine and rarely a 
creatine, the author is led to believe that the same amido* 
acids generally yield merely hydantoines. 

Three Odlocblorophenols.— £t. Barral.— These odo- 
chlorophenols possess certain identical properties which 
are also common to hexachlorophenol :— (z) Redudion to 
pentachlorophenol by tin and hydrochloric acid ; (3) de- 
composition by heat into chlorine and produds containing 
perchlorodioxyphenylene ; (3) formation of pentachloro- 
phenol acetate with acetic anhydride. These isomeric 
odochlorophenols are much more stable than hexachloro- 
phenol. They are perchloro* acetones, differing from 
hexachlorophenol by CI3 ; that is, trichlorides of p$nta» 
chlorO'CyclO'hexa-ditneont in which the position of the 
three atoms of chlorine has yet to be determined. 

Hezamethyleneamine. Adion of Pbenylhydrasin 
Hydrocblorate. — M. Delepine.— Here we have the total 
elimination of the typical hydrogen. Methylenepheoyl- 
hydrazin, CHaCHa-N— NH-CeHj, which would cor- 
respond to the general formula of the phenylhydrazin 
aldehyds, still reads upon formic aldehyd to yield tri« 
methyleoe-diphenyldihydrazin. 

Hezamethyleneamine Cbloromercurates and lodo- 
mercurate.— M. Delepine.— The author has obtained 
three cbloromercurates and one iodomercurate, and con> 
aiders it certain that by varying the conditions we may 
augment their number on account of the multiplicity of 
basic fundioos in the molecule. 

Novel Readions of Morphia. — G. Bruylants. — ^Al- 
ready inserted. 

Untrustworthiness of Cremometers for Deter- 
mining the Patty Matter in Pasteurised Milk.— P. 
Cazeneuve and £. Haddon. 

Sterilisation of Milk, and on Ladtic Permentatioo. 
P. Cazeneuve. — The author's conclusions are : — z. If it 
is true that a heat of zzo" (Pasteur, Hueppe) for half an 
hour is required to kill the ladic ferment, a temperature 
of 98** to 100*^ applied for an hour often destroys it, and 
in all cases attenuates it so far as to render it sterile in 
deoxygenated milk. As for the pathogenic ferments they 
are certainly destroyed. 2. In industry the apparatus 
which I have described permitting the complete immer- 
sion in boiling water of the sterilising bottles and the total 
deoxygenation of the milk and the containing vessel secures 
its indefinite preservation without any savour of rancidity 
and without coagulation. 3. Milk at 98^x00* has 



i86 



Chemical Notices from Foreign Sources. 



f Crbmigal Nbws, 
I Oa. XX, 1895. 



digestive properties, as demonstrated by clinical observa- 
tion and experiment (Dr. Rodot), at least equal to those 
of raw milk, whilst it has the well known superiority of 
not being the vehicle of certain contagious microbia fDr. 
Budin, &c.). It has the advantage over milk boiled at 
xzo— 120^ of not turning yellow, and not taking a taste 
of burning or of peptone so frequently met with in milks 
sterilised at this temperature. 4. My observations have 
permitted me to establish that the ladic ferment appears 
little dififused in the air. Milk is chiefly contaminated by 
contad with impure objeds. 

Mordant of Glucina.— Maurice Prudhomme.— In pre- 
paring the mordant the author sets out with a crystalline 
glucinium sulphate, free from iron, and containing merely 
traces of alumina. 10 grms. of this sulphate were dis- 
solved in 75 C.C. of distilled water, precipitated with am- 
monia, and pure ammonium carbonate is added to the 
solution. After twenty-four hours, it is filtered and 
heated in the water-bath to expel any excess of ammonium 
carbonate. The deposit of glucinium carbonate is re- 
dissolved in acetic acid and the mordant is made up to 
zoo c.c. The cloth worked in this bath is dried in the 
stove, aged for twenty-four hours in a moist atmosphere 
at about 35S and dunged in a dilute solution of ammonia 
at 6qP. The swatches took a garnet shade corresponding 
to violit-nd z, 4/10 black of Chevreul's chromatic circle. 
The author concludes that glucina behaves as a protoxide 
and not as a sesquioxide from a tindorial point of view* 



MISCELLANEOUS. 

Impurities in Milk.^The Medical Press of Odlober 
and quotes Dr. Buckhaus, of Berlin, that this city con- 
sumes in its milk-supply 3 cwts. of cow-dung. Whether 
this is the daily consumption of so unsavoury an addition 
we do not learn. 

Diamonds. — According to the Chemiker Zeitung a 
diamoodiferous rock has been discovered on the River 
Kamanka, in the Southern Ural. The diamonds are said 
to resemble those of Brazil, having a purer water than 
those of South Africa. 

Discovery of Saltpetre at the Cape. — Attention 
has been called from time to time to the importance of 
searching for deposits of potassium salts in the Colonies 
and India. According to South Africa it appears that 
beds of earth rich in potassium nitrate have been dis- 
covered in the Cape Colony, and are now being worked 
on a pradical scale. Samples have been found containing 
as much as 70 per cent of this valuable salt, but the 
average seems to range from Z2 to Z5 per cent. Of course 
the extent of the deposits has not yet been determined. 
The value of this discovery, if the supply is considerable, 
is beyond question. 

Influence of the Presence of Lead Acetates on the 
Results of the Determination of Inverted Sugar by 
the Pehling-Soxhlet Method.— Arthur Borntrager.— 
The author confirms the statement of C. H. Gill, which 
appeared in a paper on the examination of glucose-con- 
taining sugars, read before the Chemical Society, March 
z6, z87Z. Gill arrived at the conclusion that in presence 
of basic lead acetate, solutions of invert sugar seem to 
have a less redudive power than in the absence of the 
lead salt. Borntrager expresses his regret that he did not 
meet with Gill's original paper, but only imperfeA, and to 
some extent misleading abstraAs. — Deutsche Zucker- 
Industrie t August 9, 1895. 



Bbrata.— The title of the paper by Messrs. Auden and Fowler 
(p. X63) should read *' The Aaion of Nitric Oxide on Ceruin 
Salts/instead of" Nitric Acid:* P. 114, Queen's College, Cork, /or 
•* Assistant— D. J. O'Mahonjr, F.C.SV'fM^*' Deffloottrator— R. B. 
Doran, F.C.S." 



J. & A. CHURCHILL, 
PU BLISHER S, 

PRACTICAL CHEMISTRY AND 

QUALITATIVE ANALYSIS: Specially adapted for Colleges 
and Scbeols. By FRANK CLOWES, D.Sc, Professor of Che- 
reistry in University College, Nottingham. Sixth Edition, with 
84 Engravings, Post 8vo, 8s. ^, 

ELEMENTARYQUALITATIVE ANA- 
LYSIS; suitable for Organised Science Schoola. By FRANK 
CLOWES, D.Sc. Lond., Professor of Chemistry in Uniyenity 
College, Nottingham, and J. BERNARD COLEMAN, Head of 
the Chemical Department, South* West London Polytechnic. 
W ith Engravings. Post 8vo, 2s. M, 

BY THE SAME AUTHORS. 

QUANTITATIVE ANALYSIS: specially 

adapted for Colleges and Schools. Third Edition, with 106 En- 
gravings, Post 8vo, 9s. 

VALENTIN'S QUALITATIVE ANA- 

LYSIS. Edited by Dr. W. R. HODGKINSON. F.R.S.B., Pro- 
fessor of Chemistry and Physics in the Royal MiliUry Academy 
and Artillery College, Woolwich. Eighth Edition, Revised and 
Enlarged, 8s. 6^. 

BLOXAM'S CHEMISTRY, INOR- 

GANIC AND ORGANIC, with Experiments. Re-written and 
Revised bv JOHN MILLAR THOMSON, Piofessorof Chemis- 
try. KingVi College, London, and ARTHUR G. BLOXAM, 
Head of the Chemistry Department, The Goldsmitha* Inatitnte, 
New Cross, London. Eighth Edition, with 282 Engravings, 8vo, 
i8i. 6<f. 

BLOXAM'S LABORATORY TEACH- 

ING; Or, Progressive Exercises in Praftical Chemistry. 
Edited by ARTHUR G. BLOXAM, Head of the Chemistry 
Department, The Goldsmiths' Institnte, London. Sixth Edition. 
Revised and much Enlarged, with 80 WoodcnU, Crown 8vo, 
6s. 6d, 

CHEMISTRY OF URINE; a Pra«5lical 

Guide to the Analytical Examinations of Diabetic, Albaminoua. 
and Gouty Urine. By ALFRED H. ALLEN, F.I.C., E.G^S. 
With Engravings, 8vo, ys. 6d, 

London : 
J. & A. CHURCHILL, 11, New Burlington Street. 

ACETONE — AoBwcring all reqnirementt. 

.A.CXZD J^OETIO— Pure»t and sweet. 

- BOiR-A-OIO— Cryit. and powder. 

OI'-L'_fcOlO— Cryil. made in earthenware. 

Q--A.IjIjIO— From best Chinese galla, pore. 

S-A-IilOYIjIO-By Kolbe'a process. 

- T-A.K"3^IO— For Pharmacy and the Arta. 

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FORMALIN (4075. CH3O)— Antigeptic and Preservative. 

POTASS. PBRMANGANATE-Cryat., large and anuOU 

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BARIUM. 

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CbbmicalNbws,! 



Constitution of Camphoric Acid. 



187 



THE CHEMICAL NEWS 

Vol. LXXIL, No. 1873. 



ON THE SENSITISING ACTION OF DYES ON 

GELATINOBROMIDE PLATES.* 

(Abstract). 

By C. H. BOTHAMLEY, F.I.C.. P.C.S. 

Although many dyes have been examined since H. W. 
Vogel's discovery in 1873, very few of them exert any 
marked tBt£t in making gelatinobromide plates sensitive 
to the less refrangible rays of the spearum. Only 
cyanin and the dyes of the eosin group (including the 
rhodaminet), with perhaps malachite-green, alizarin-blue, 
and chrysoidine, exert any praftically useful eflfeia. 

The main points established by previous observers may 
be summarised aa follows :~(x) all the dyes that ad as 
sensitisers are readily affeded by light when in contaa 
with paper, fabrics, &c. ; (2) in order that a dye may ad 
as a sensitiser it must have the power of entering into 
intimate union with silver bromide, forming a kind of 
lake ; and (3) it must show a strong absorption-band for 
the particular rays for which it is to sensitise. It is 
important to observe that the converse of these state- 
ments is not necessarily true, since several dyes that 
have all these properties show no appreciable sensitising 
adion. 

Experiments by Dr. E. Vogel on the rate of fading and 
the sensitising adion of the eosin dyes, led him to the 
conclusion that the order of sensitising effed coincides 
with the order of fadine when the dyes are exposed to 
light. The order in which he places the dyes does not, 
however, correspond with the order of fading as observed 
in dyed fabrics, and the experimental method that he used 
is open to criticism. . , ,. 

The author's observations on the fading of the various 
sensitisers when exposed to light in contad with gelatin 
alone, led him to the conclusion that, although all the 
sensitisers are readily affeded by light, the order of sensi- 
tising efifea does not necessarily correspond with the 
order of fading, whether the dyes belong to the same 
chemical group or not. . 

There are two chief hypotheses as to the mode m 
which the dyes ad, namely, (i), the view held by Abney, 
that the dye itself is oxidised by the adion of light, the 
oxidation produd remaining in contad with the silver 
bromide ; and when the plate is treated with the deve- 
loper, the latter and the oxidation produd, ading simul- 
taneously on the silver bromide, bring about its redudion ; 
and (a), the view first definitely formulated by Eder and 
endorsed by Vogel, namely, that the energy absorbed by 
the dyed silver bromide is partially used up in bringing 
about the chemical decomposition of the silver bromide, 
instead of being almost entirely converted into heat as 
when absorbed by the dye alone. 

The author has found that the less refrangible rays will 

Sroduce a photographic image on the sensitised gelatino. 
romide plates when they are immersed in powerful 
reducing solutions, such as a mixture of sodium sulphite 
and pyrogallol. This holds good for cyanin, the eosm 
dyes, the rhodamines, and quinoline-red, whether the 
sensitiser has been added to the emulsion or has been 
applied to the plate in the form of a bath. It is therefore 
impossible to attribute the sensitising effed to any inter- 
mediate oxidation of the dye. 

Experiments with various reagents, such as potassium 
bromide, potassium dichromate, mercuric chloride, and 

* Read before the British Asiociatioo (Sedton B), Iptwich 
Meeting, 1895. 



dilute hydrogen peroxide, seem to show that the chemical 
nature of the latent image produced by the less refiran- 
gible rays on the specially sensitised plates, is precisely 
the same as that of the latent image produced by the more 
refrangible rays in the ordinary way. 

Further proof in the same diredion is afforded by the 
fad that the effed of the sensitisers extends to the 
produdion of a visible effed by the prolonged adion of 
light. 

The balance of evidence is therefore greatly in favour 
of the view that the dye absorbs the particular groups of 
rays, and, in some way which is not at all clear, hands on 
the energy to the silver bromide with which it is inti« 
mately associated, and which is thereby decomposed. 



MOTE ON THE 

CONSTITUTION OP CAMPHORIC ACID.* 

By J, J. SUDBOROUGH, D.Sc.. Ph.D., F.I.C.. 
Ledorer 00 Organic Cbemittry, UniversKy College, Nottingham. 

The behaviour of camphoric acid on esterification (J. W. 
Briihl, Ber,, 1893, xxvi., 2S4) is very similar to that of 
some of the aromatic polycarboxylic acids investigated by 
V. Meyer and Sudborough (B#r., 1894, xxvii., 3x46). 
These authors have shown that a carboxylic group which 
has substituting groups in the two ortho-positions is in- 
capable of yielding an ester under the usual treatment 
with alcohol and hydrogen chloride. Thus, mellitic acid — 

COOH 



COOH.C /\ C.COOH 
COOH.C I J C.COOH 



y 



COOH 

gives no ester. Pyromellitic acid— 
COOH 

C 
HC /\ C.COOH 

COOH.C [} CH 

COOH 

gives a neutral ester, C6Ha(COOEt)4. 
acid— 

C.COOH 

C.COOH 

CCOOH 

COOH 

gives a dialkvlic ester, C6Ha(COOH)2(COOEt)a. 

Wegscheider {Monaishift, 1895, xvi., 75) has since 
shown that hemipinic acid^- 

C.OMe 



And prehnitic 





* Read before the British Association (Scdioo B), Ipawich 
Meeting 1895. 



188 



Chemical Researches and Spectroscopic Studies. 



fOBnacALllBvs, 
1 Oa.t8,ifl9s- 



which is a dicarboxylic acid, yields a mono- alky lie ester, 
and thus resembles camphoric acid very closely indeed. 

It if true of both herotpinic and camphoric acid that if 
the esterification is carried out for some time at the 
boiling-point of the alcohol, small quantities of the neu- 
tral ettert are also formed ; the main produd, however, 
is always a mono-alkylic ester. 

The reason for such behaviour is, bejrond doubt, to be 
sought for in the stereo-chemistry of the molecule, the 
ortho-substttuting groups hindering the adion of the 
reagent which is employed. 

This view has received support from the recent investi- 
gations of V. Me3rer on the esterification of many other 
aromatic acids, and also from those of the author on substi- 
tuted benaoyl chlorides and bensamides (youm. Chtrn, 
Soc., Z895, 5^ *^^ ^i)* Whether we regard the substi- 
tuting groups as filling up the space and thus preventing 
the formation of some intermediate additive compound, as 
Wegschetder suggests, or whether we regard them as 
simply preventing the entrance of the alkylic groups into 
the molecule, is of no importance in the present dis- 
cussion. 

We are thus, to some extent, justified in concluding 
that the charaderistic behaviour of camphoric acid on 
esterification is due to stereo- chemical causes. Any con- 
ttitutional formula proposed for the acid should therefore 
indicate stereo-chemical grounds for such behaviour. 

If we take three of the formula which have been more 
or less generally accepted, viz.— 



CHa 
HaC /\ CILCOOH 

MeHC IJ C(Me)COOH 
CHa 

Armstrong* 

CMea — 



CHa CH.COOH 



CHa 



CMea 

C.Me.COOH 
Bredt 



J 



CH.COOH 

CHa 

HMe CH.COOH 

TiimoHH. 



we find that in no case have we a carboxylic group which 
has substituting groups in the two ortho- positions. In 
the formulflB of Armstrong and of Bredt, however, one 
carboxyl is ortho-substituted on the one side, and then 
has a methyl ^oup attached to the same carbon atom to 
which it is united. It may be that this methyl group has 
a similar influence from a stereo-chemical point of view 
as a methyl group in the ortho position. If this is really 
so, then we can see sufficient grounds for the analogy 
between camphoric acid and hemipinic acid. If, however, 
we take the formula recentlv suggested by Tiemann {Btr., 
1895. xxviii., 1079) we see that both carboxylic groups are 
similarly situated ; they both have substituting groups in 
one ortho position, but not in the other; and, further, 
neither has a substituting group attached to the same 
carbon atom to which it is united. We thus see no reason 
why one carboxyl should behave differently from the other 
on esterification. It must be pointed out that hemipinic, 
mellitic, and the other acids are all benxene derivatives, 
whereas camphoric acid, according to Armstrong, is a 
hexamethylene derivative, and according to Bredt and to 
Tiemann a pentamethylene derivative. J. van Loon has 
recently shown {Btr,, 1895, xxviii., 2270) that polycarb- 
acids of the hexamethylene series, #.^., hvdromellitic and 
isohydromellitic acid, behave very similarly to the acids of 
the bensene series, except for the difference that is caused 
by cis- and trans-isomensm. 



ON SOME STILBENE DERIVATIVfiS.* 
By J. J. SUDBOROUGH, D.Sc, PhJ)., FJ C. 

Thb author has prepared monocbloro-, methyl-chloro-, 
and ethyl-chloro-stilbene by the adion of phosphorus 
pentachloride on deoxybenxoln and on its methyl and ethyl 
derivatives. The monochloro-stilbene differs from that 
described by Zinin (AnnaUnt cxlix., 375), as it is a solid, 
which crystallises from alcohol in large colourless plates* 
It melts at 53°— 54^ and yields additive compounds with 
bromine, with chlorine, and with " nitrous acid." These, 
together with the corresponding compounds obtained from 
methyl- and from ethyl-chloro-stilbene, are described. An 
oily monochloro-stilbene, corresponding to that of Zinin, 
has also been prepared, and is being subjeded to further 
examination in order to determine whether it is merely an 
impure form of the crystalline compound or a true stereo- 
isomeride. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 
STUDIES OP VARIOUS ELEMENTS. 
By JBAN SBRVAIS STAS. 
(Ooatinoad from p. 179). 

To have the air motionless, at the tame time, outside and 
inside a closed room, however large, is a condition so rare 
that almost all spedroscopists acknowledge that the so- 
dium D line is always seen in a Bunsen oumer or in a 
blowpipe fed with hydrogen. 

When one has a chance of having the air relatively 
pure, the disturbance which one is obliged to make one's 
self in the room in order to work soon stUltes the purity 
of the medium. 

I have ascertained that the time suitable for the »• 
periments themselves is vei^ small ; it is at the most an 
hour and a half a day ; and it is only in the morning, from 
9 to II o'clock, when the external air has been saturated 
with moisture for several days, that we can hope to find 
it at Brussels, on condition of having taken care to wash, 
with plenty of water, the floor and the walls of the room 
the previous evening, in order to rid one's self, so far as 
may be, from dust accumulations, of having admitted 
thither air saturated with moisture, of keeping the floor 
wet, of refraining from walking about the room, and of 
only being helped by a single assistant or a single witneaa. 
When the floor is dry and the air of the room is disturbed 
by walking about, or by draughts caused by the doors, 
by the window-shutters, and above all by the roof of the 
room, the pure deep blue colour charaderistic of the flame 
of a Bunsen burner alters towards indigo, to become 
finally a distind violet, and even reddish ; one then often 
observes in it bright points which give a yellow light. 

The prismatic analysis of the flame shows in it the 
existence of sodium and calcium in an intermittent or 
continuous manner, according to the magnitude of the 
disturbance of the air. The introdudion of hydrochloric 
acid in this flame allows one to see the spedrum of cal- 
cium with great relative clearness. 

In air disturbed b^ motion, the invisible flame of pure 
hydrogen, the blowpipe flame of hydrocarbon in air, or of 
oxyhydrogen, turns distindly yellow, often even red, 
and becomes very bright. The colour and brightness of 
this flame increases with the magnitude of the dis- 
turbance. 

The difficulties against which one has to strive whilst 
one is attempting to ascertain the truth of fads, do not 
include simply such impurities as the ordinary air may 
contain, but depend equally on the state of purity of the 
ga&es employed and of the apparatus through which one 



* Read before the British AMOciation (Sedioo B), Iptwich 
Meeting, 1899. 



Chemical Researches and Spectroscopic Studies. 



CBUMtOALNEWf,! 

oa. 18, 1895. / 

passes them, or on the burner in which one completes 
the combustion of them. 

It is essential that the illominating gas, hydrogen, air, 
and oxygen which feed the blowpipes shoald themselves 
be entirely freed from suspended particles of sodium or 
calcium. 

I have fonnd that one of the best and surest methods 
of purifying illuminating gas, hydrogen, oxygen, and air 
from all suspended particles, is to let them pass through 
pure boiling water, and to pass them into and store them 
for at least twenty-four hours undisturbed in large gaso- 
meters, over water free from volatile bodies and made 
alkaline by lime or baryta. 

When afterwards used they do not show any trace of 
the spedrum of sodium or calcium* 

It is so difficult to deprive dry air in motion of sus- 
pended matter, that one distindly notices the presence of 
sodium in the flame of a platinum or silver blowpipe 
when fed with hydrogen or purified illuminating gas, and 
either external or internal air supplied and purified by 
its passage through water-bellows or a water-pump. I 
have only succeeded in removing the sodium which is 
contained in insoluble suspended particles from the exter- 
nal or internal atmosphere, even with the assistance of a 
water-pump, by passing it through a metal heater con- 
taining pure boiling water. 

Havinf regulated the supply of purified air and the 
boiling of the water, so as to obtain a supply of air and 
water vapour in nearly equal volumes, the condensation 
of steam, during its passage along a condenser of well- 
polished tin, ensures the deposit of such insoluble par- 
ticles as ma^ have survived the purification by the pump, 
and thus gives, when using either illuminating gas or 
pure hydrogen, a blowpipe flame in which spedlrum 
analysis does not enable one to deted the sodium line, it 
being well understood that the air of tht room or of a lofty 
and comparativily confimd clont^ with damp walls, in 
which one is working, is itself entirely freed from sodium 
particles. 

The steam, when condensing, deposits with itself the 
insoluble matter suspended in the air supplied by the 
bellows or the pump. 

I have tried an experiment, on s very large scale, for 
the purpose of ascertaining the weight of sodium parti- 
cles thus eliminated. I worked during a moderate 
southerly breeze, on air taken from the street in which I 
live, running from east to west, 9 metres above the 
frround, which is about 50 metres above the surface of the 
river running through the town, and about 67 metres 
above sea-level. Whilst the apparatus was working I 
took pains to satisfy myself, by several repetitions, that 
after the condensation of steam the air mixed with it was 
completely free from sodium particles. 

The condensed water, as it was formed, was passed 
through a double filter-paper that had been freed by a 
simple process from all traces of mineral matter, and held 
in a covered platinum funnel. I found that the combus- 
tion, in a closed vessel and at the lowest possible temper- 
ature, of the double filter, through which had passed tin 
lUns of water after the pump had been working for six- 
teen hours, only left 0*00023 grm. of brown ferruginous 
Mh,~that is to say, 23/10,000,000 of its weight, sup- 
posing, be it understood, that not a particle* of suspended 
matter had been retained in the well-polished tin con- 
denser. The volume of air supplied by the pump to the 
distilling apparatus amounted to about 17 cubic metres. 

In whatever manner the water was colleded into a 
glass jar, it was impossible for me to deted in it, by 
spedrum analysis, the slightest sign of the sodium line. 
The water-pump, therefore, had robbed the air of its 
soluhU compounds of sodium ; on the other hand, the 
brownish ash, having been moistened with hydrochloric 
acid freshly prepared in the platinum dish, and intro- 
duced into an hydrogen flame on the end of a platinum 

•A filter of good paper, treated succettively with hydrochloric and 
bydroflaoric sods, left no trace of ath when burnt. 



189 



loop, at once coloured it a brilliant yillow^ and with the 
spedroscope I recognised the presence of calcium and 
sodium. 

The last remaining cause of the difficulties which one 
meets in spedrum analysis, when one attempts to %6ivt 
important questions, rests in the apparatus used for pro- 
ducing the flames. 

As regards platinum, experience has taught me that by 
melting and refining one rids it entirely of sodium. As 
a matter of fad I have never succeeded in deteding the 
appearance of the sodium line in platinum which has 
been purified by re-melting in the air in an oxyhydrogen 
blowpipe. I have noticed, on several occasions, t^at 
platinum which had been melted in a lime crucible, on 
being re-melted in an oxyhydrogen flame, gave temporarily 
a calcium spedrum. Whatever the reason might be, 
when made into either sheet or wire, the re-melting in air 
got rid of the calcium. 

If platinum which has been kept for some time in air, 
iVin protected from dust, be put into the flame of a Bunsen 
burner or an hydrogen flame, it at once colours them 
yellow and shows the sodium line, but never a calcium 
spedrum, not even when moistened with ' hydrochloric 
acid. The fad that these flames turn yellow, first noticed 
by Messrs. Bunsen and Kirchhoff, is known by all spedro- 
scopists. This colour disappears when ths metal is raised 
to a white heat. 

If platinum which has been lying in air, either in a 
room or outside, and unproteded from the dust, be put 
into the flame of a Bunsen burner or an hydrogen flame, 
it colours them yellow tinged with red : this colour lasts 
so long as the platinum has net been melted and refined 
in a lime crucible, or even if it has not been treated when 
warm with a mixture of hydrofluoric and hydrochloric 
acids diluted with their own weight of water. I have 
ascertained that the particles suspended in the air, both in 
the room and outside in the town of Brussels, which are 
insoluble in water, include, besides organic salts, silicates 
of alumina, calcium, iron, and sodium, carbonate of cal- 
cium, and silica. I have looked for potassium without 
being able to find it. 

Experience has taught me that the tubes and fittinn 
of platinum intended to be used in accurate spedroscopic 
researches ought to be kept proteded from atmospheric 
dust, and before making use of them it is essential to give 
them a cleaning with dilute hydrofluoric and hydrochloric 
acids, and then with distilled water. I have ascertained 
as a fad that it is in the form of a fused silicate that the 
sodium remains on the surface of dusty platinum which 
has been raised to a white heat. 

I have mentioned above that pure platinum, if kept 
some time in air and protected from dust, colours the 
flame of a Bunsen burner yellow, and gives the sodium 
line. 

I tried some experiments to make sure of this fad, and 
found that pure platinum— either wire, sheet, or spongy — 
can be kept a great length of time in the damp open air, 
as well as in an air current issuing from a gasometer 
where it has been stored over water for twenty-four 
hours, and whence it issues saturated with water*vapour, 
without acquiring the power of colouring an hydrogen 
flame yellow, or giving the slightest trace of the sodium 
line. 

It is the same with air purified by passing it through a 
metal boiler filled with boiling water, as I have explained 
above. This air is so completely free from sodium that 
not only can one leave platinum in it without contami- 
nating it with sodium, but one can pass a spark from a 
powerful indudion-coil through it, between platinum 
points or points of platinum covered with iridium free 
from soda, and still a spedrum analysis of the spark does 
not show the sodium lines among the atmospheric lines 
{see Note). This image can always be seen in the spark 
made in so-called pure air, even when hydrogen and tllU' 
minating gas can be burnt in it without showing th$ 
I presence 0/ sodium in the spectroscope. When describing 



190 



Citric and Tartaric Acids from Cane-sugar. 



i Cbbmical Nbws, 
T oa. i8, 1895. 



the t[ 
last faa. 



ipeArotcopic study of lithium I shall return to this 
faa. 



(Note.— I made this experiment in an apparatus the 
details of which are known. It consisted, shortly, of a 
tube of hard colourless glass, 12 cm. long, 8 cm. internal 
diameter, and zo cm. external diameter. 

A disc of hard glass, ground and polished on one side, 
2 cm. thick and 10 cm. diameter, was fixed on either 
open end of the tube by means of clamps held together 
by metal rods with screwed ends. Each disc was pierced 
in the middle with a slightly conical hole, about z cm. 
diameter, into which was carefully fitted a plug of pure 
silver, terminating outside in a small ring, meant for 
making conta^ either with the coil or the condenser. In 
the end of the conical silver plugs which pierced the discs 
was drilled a deep cylindrical hole i\ m.m. in diameter, 
and tapped, for screwing in one of the ends of a platinum 
rod of the same diameter, whose end was also screwed. 
To the other end of the platinum rod was attached a ball 
of the same metal, 3 m.m. in diameter, or a ball of plati- 
num coated with pure iridium which had been fused on 
with the oxy-coal-gas blowpipe. 

The distance between the platinum balls is adjusted 
by screwing the ends of the platinum rods more or less 
deeply into the screw holes in the silver plugs, which are 
kept in the discs by fridional grip. After some trials I 
varied this distance between 5 and zo m.m. 

In the middle of the space between the hole pierced in 
each disc and the inner surface of the tube is drilled a 
second hole, 6 m.m. in diameter, into which is fitted, by 
grinding with emery, a hard glass tap, so as to provide 
each disc with a tap for letting the air to be submitted to 
the ele^ric discharge into the tube. 

With the exception of the silver plugs and their exten- 
sions, the platinum rods and balls used as eledrodes, the 
apparatus was made of hard glass, of which all the parts 
in mutual contact were ground and polished with emery, 
and kept pressed one against the other in such a manner 
as to form an air-tight chamber, and preserve by atmo- 
spheric pressure the air which was contained in it. 

In order to rid the apparatus of all traces of free sodium 
compounds I made the following arrangements. After 
having washed the apparatus, snort of its silver plugs, 
several times with pure water, I put it, whilst it was still 
wet, by means of the taps fitted to it, in communication 
with the gasometer containing the air which I wished to 
examine, and passed a rapid current of this air through it. 
I then adjusted the silver plugs and their extensions, the 
platinum rods and balls, which had just been washed, first 
with dilute hydrofluoric acid and then with pure water, 
which had been distilled and condensed into the platinum 
funnel. 

The balls of pure platinum, or of platinum coated with 
pure iridium, having been first set to the required interval, 
and the apparatus having been fixed vertically in front of, 
and as near as possible to, the slit of the spe^oscope, I 
passed alternately sparks and a brush discharge between 
the balls, whilst a current of the air under examination 
passed through the apparatus. 
This current of air was fupplied :— 
z. By a gasometer in which the external air, washed 
simply by the pump, had remained for twenty-four 
hours over water made alkaline by baryta. 
2. By a gasometer in which was received aired the air 
delivered by a water-pump into boiling water con- 
tained in a copper boiler surmounted by a chamber 
communicating with a tin refrigerator, which was 
kept at a low temperature by ice constantly re- 
newed in order to condense the steam mixed with 
an almost equal volume of air from the pump. 
When working in this manner, I observed that spec- 
trum analysis, whether of the spark or brush discharge, 
however powerful they were, showed a spedrum without 
the double D line. With the spark long or short I ob- 



served only the spedrum of atmospheric lines, and with 
the strong spark the speArum of these latter lines, near 
to which appeared some bright lines, due either to 
platinum or iridium, according to the material of the tor* 
face of the balls used. 

For this purpose I used in succession M. Hilger's direA- 
vision spedroscope, Steinheil's spedroscope, and lastly, 
M. Dubo8cq*s large speAroscope with three prisms. 

The absence of the yellow sodium line in the spedmm 
of the eledric current passing through air saturated with 
moisture and purified by the methods described above, 
surprised the spedtroscopists to whom I told my results. 
I will say in support of the perfed accuracy of this re- 
search, that during the revision of my spedtroscopic 
studies with M. Depaire, we both decided, after several 
trials, that we could not see the yellow sodium line in the 
spedrum of a discharge passed through the partially 
saturated air in his spedroscopic laboratory. 

Trying one day if we could obtain a compound of mag- 
nesium sufficiently free from sodium as not to show the 
sodium line on speArum analysis of the spark through it, 
we not only ascertained the possibility of attaining this 
entire freedom, but we found also that the surrounding 
air, which fed the tube on which we were engaged, was 
free of sodium. 

With the hope of being able to learn something of the 
nature of the substance which occasionally gave to the 
hydrogen made by water eledtrolysis, or by the decom- 
position of xinc or of xinc and lead by dilute sulphuric 
acid, the property of burning with a ruddy ytllow flame, 
I filled the apparatus described above with hydrogen 
having this property, and whilst the current was passing 
through it I made a spedroscopic examination of the 
spark, weak or strong, passed through it. 

I noticed that near the sodium line and the C and F 
hydrogen lines, the spedrum showed some faint lines, 
both red and distindly green, grouped like nitrogen lines, 
and whose position coincided with that of nitrogen lines. 

The presence of nitrogen is accounted for, since the 
hydrogen was colleded and stored over aerated water. 

Having replaced the gas with hydrogen deprived of 
the power of burning with a slightly visible flame, I proved 
by a spedroscopic examination of the spark through this 
gas the absence of the sodium line in the spedrum; but 
the presence, fully as noticeable, of the faint red and 
green lines seen in the gas endued with the property of 
burning with a visible flame. 

The nature of the substance which, in certain condi- 
tions, gives hydrogen the property of burning with a ruddy 
flame remains to be discovered). 

(To be coatiaaed). 



CITRIC AND TARTARIC ACIDS FROM 

CANE-SUGAR. 

(THiitD Note). 

By Dr. T. L. PHIPSON. 

Although I have not finished my investigations on this 
subjed, I hasten to reply to those chemists who have not 
succeeded in obtaining the results alluded to in mv former 
notes. It is easy to point out where their error lies, but 
it will perhaps not be so easy to get them to acknowledge 
it. They have failed to obtain the produds by oxidation 
because they have not employed a sufficient quantity of 
permanganic acid. If they had jotted down the propor- 
tions requisite to supply the needful quantity of oxygen 
in order to convert cane-sugar to citric acid, they would 
have found that it requires at least as much permanganate 
as the weight of sugar employed. No lime precipitates 
of organic acids are obtained with small quantities, and 
hence the errors of observation alluded to. 
. These gentlemen all assert that the precipitate on boil- 



Cbbmical Nbws, \ 

oa. i8, 1895. f 



Separation of Arsenic from other Elements. 



191 



iog consiBts of sulphate of lime with 00 trace of organic 
acid, and that when nitric acid is used instead of sul- 
phuric acid to acidify the sugar solution, no precipitate is 
obtained. 

Here is an experiment made without sulphuric acid, in 
which nitric acid alone was used : — 

Equal weights of sugar, nitric acid, and permanganate 
of potash are taken, and the mixed solution is left for 
twenty-four hours in the cold. The clear solution is 
neutralised by carbonate of lime, which occasions a 
copious precipitate. The clear liquid from this precipi- 
tate, when boiled, yields a further smaller precipitate. 
The first contains tartaric acid, and perhaps saccharic 
acid, which has the same composition as citric acid. It 
is soluble without effervescence in acetic acid, and there- 
fore contains no oxalic acid nor carbonic acid. The 
second precipitate is citrate of lime. 

If the clear liquid, instead of being neutralised by car- 
bonate of lime, is almost neutralised by carbonate of 
potash, and stirred with a glass rod whilst still acid, bi- 
tartrate of potash is precipitated. The liquid filtered from 
the lime salts contains the whole of the manganese. 

The Cata Mia Laboratory, Putney, 
Oaober 20, 1895. 



THE SEPARATION OF ARSENIC FROM 

OTHER ELEMENTS BY MEANS OF METHYLIC 

ALCOHOL AND HYDROCHLORIC ACID. 

By CARL FRIEDHEIM and PAUL MICHAELIS. 

Thb method proposed by Schneider and almost simulta- 
neously by Fyfe, subsequently repeatedly tested and 
modified,-*!. #., to separate arsenic from other elements 
in the state of a volatile trichloride, by means of hydro- 
chloric acid or sodium chloride and sulphuric acid, — has 
been re-modelled in a much more useful and generally 
applicable state by E. Fischer, who effeds the distillation 
in certain conditions after the addition of ferrous chloride 
and hydrochloric acid. Hufschmidt, as also Classen and 
Ludwig, expedite the elimination of the arsenic in an 
extraordinary degree by the introduAion of gaseous 
hydrochloric acid. 

If this method is used for separating arsenic from other 
metals precipitable in an acid solution by means of sul- 
phuretted hydrogen, the presence of ferric chloride at most 
presents the disadvantage that sulphur is carried down 
along with the sulphides. But if nickel, cobalt, and 
other elements of the ammonium sulphide group are 
present, their determination in the same specimen becomes 
very difiScult, and that of iron impossible. 

Also in the separation of arsenic from tungsten, vana- 
dium, and molybdenum, in company with which it is found 
in numerous so-called complex combinations, the above- 
mentioned method would be as good as inapplicable. 
Tungsten would be in part separated out during the dis- 
tillation, and have a disturbing influence. On the other 
hand, in consequence of the presence of the great quan- 
tity of ferrous chloride, it could scarcely be precipitated by 
concentration. The determination of vanadium by pre- 
cipitation with mercurous nitrate would be rendered diffi- 
ctilt by the simultaneous precipitation of mercurous 
chloride, and molybdenum could be separated from iron 
only by means of ammonium sulphide, which is neither 
accurate nor convenient. 

In nearly all these and in numerous other cases we 
have found it preferable to substitute for ferrous chloride, 
methylic alcohol, because after distillation it leaves behind 
no fire-proof substance, but at most some carbon which is 
easily filtered or burnt off. 

I. Behaviour of Arstnic Acid with Mtthylic Alcohol and 
Oastous Hydrochloric Acid. Modus operandi. 
Arsenic acid, on treatment with methylic alcohol and 
hydrochloric acid, is not esterified as such, but reduced to 



arsen-trioxide, which then seems to evaporate in the form 
of its ester, a view supported by the circumstance that an 
anhydrous distillate is not precipitated by hydrogen 
sulphide unless decomposition has first been set up by the 
addition of water. 

If the methylic solution of arsenic acid saturated with 
hydrochloric acid gas (0*2 to 0*3 grm. AsaOs, in 40 to 50 
c.c. CH3.OH) is heated in a distillation flask on the 
water-bath, arsenical vapours are given off at 40° to 50^ 
(thermometer in the flask), the main quantity following 
at 65° to go**. A repetition of the operation yields only 
small quantities of arsenic, and on a third distillation 
the contents of the flask and the distillate are usually free 
from arsenic. 

As the distillatory method it is convenient to use a 
round flask holding 250 c.c, which can be closed by 
means of a cap, ground to fit, and melted on to the con- 
denser. Through this there passes (ground to fit) a 
dropping-funnel, which reaches almost to the bottom of 
the flask. The liquid distilling over flows into a flask of 
the capacity of about } litre through a tube, ground in as 
a stopper and extending to the middle of the flask, and 
also ground to fit the outflow of the refrigerator. 
Laterally, on the neck of the flask, there is a ground 
jundion for a three-ball receiver. 

In carrying out the distillation we proceed as follows :^> 

The solution of the substance to be analysed is mixed 
in the distillatory flask with 50 c.c. methylic alcohol, as 
nearly anhydrous as possible, and, after the reception 
flask has been charged with 20 c.c. of concentrated nitric 
acid and the three-ball receiver with distilled water, the 
development of hydrochloric acid is introduced, in order 
to prevent the reflux of the methylic alcohol. 

The dropping funnel certainly serves for the reception 
of the re-ascending methylic alcohol, but in some cases 
the liquid may spirt over into the dry bottle between the 
generating flask and the distillatory vessel, if the cock 01 
the funnel is not closed soon enough. The distillation 
flask is kept cool by means of cold water, as otherwise the 
methylic alcohol might be heated to ebullition in conse- 
quence of the absorption of the hydrochloric gas. After 
complete saturation it is distilled off from a water-bath, 
whilst a very weak current of hydrochloric gas is 
kept up. 

According to the quantity of the arsenic acid the dis- 
tillation must be repeated once or twice, or even three 
times if the methylic alcohol has been diluted with much 
water. To this end the funnel cock is closed, the distil* 
latory flask is refrigerated, the dropping funnel is filled 
with the corresponding quantity of alcohol, which is 
allowed to flow into the distillation flask. 

When all the arsenic has passed over the contents of 
both receivers are transferred to a porcelain capsule 
holding z litre, and the receivers are rinsed out with 
water, covering the capsule with a clock-glass on account 
of the rather brisk development of gas. After the addi- 
tion of 20 to 30 C.C. of concentrated nitric acid it ii 
heated on the water-bath, keeping the capsule covered 
with a clock-glass until the violent escape of chlorine hat 
come to an end. The liquid is then evaporated down to 
100 c.c. After again adding an equal quantity of nitric 
acid, and complete evaporation, the residue is taken up 
with water, filtered, and precipitated with magnesia 
mixture. 

II. Distillation of Pun Arsenic Acid, 

Weighed portions of pure arsen-trioxide were oxidised 
to arsenic acid by means of concentrated nitric acid, the 
solution completely evaporated down, the residue mixed 
with water into the distillation flask, the water evaporated 
down to 5 to zo c.c, and generally a threefold distillation 
is effeded with 50, 40, 30 c.c of methylic alcohol. The 
fourth distillate and the residue were always tested, and 
found free from arsenic. 

III. Separation of Vanadic Acid and Arsenic Acid, 
A direct separation of arsenic from vanadic acid has 



192 



Separation of Arsenic from other Elements. 



I CBBMIClt, NmvB, 



hitherto been pradicable only by reducing the latter to 
Va04 by boiling with SO21 and precipitating the arsenic 
by solphnretted hvdrogen under pressure, re-oxidising the 
vanadium in the nitrate, and, according to the nature of 
the base present, separating with HgNOj or other agents, 
or titrating in the reduced solution with permanganate. 

For the experiments we used ammonium vanadate, 
AmVOs, repeatedly re-crystallised, and containing 77*82 
per cent VaOs, and pure arsenic acid. 

On distilling AmVOs alone with methylic alcohol and 
hydrochloric acid, there passes over firstly a dark liquid 
containing vanadic acid. By degrees the distillate be- 
comes lighter, and finally clear as water, whilst the colour 
of the liquid in the distillation flask changes from dark 
brown to a blue-green. 

If 20 c.c. of water are added to the methylic alcohol 
only the first drops of the distillate have a violet colour. 
To prevent this the vanadic acid, before the addition of 
methylic alcohol, is reduced by heating with a little sul- 
phurous acid, when the distillate is from the commence- 
ment clear as water, and contains no vanadic acid. 

Before the second distillation of arsenic the water 
remaining in the flask is evaporated away as far as pos- 
sible, since a volatilisation of vanadium is no longer to be 
dreaded. 

In the following analyses the distillation was repeated 
four or five times, using at first 50 c.c. and afterwards 30 
to 40 c.c. of methylic alcohol. 

For determining the vanadic acid in the residue the 
contents of the flask were rinsed into a porcelain capsule 
by means of nitric acid, evaporated to dryness, transferred 
with ammonia into a weighed platinum capsule, and after 
evaporation and ignition the weight of the vanadic acid 
was determined. 

IV. Separation of Arsenic and Molyhdic Acids, 

In the analysis of their alkaline compounds these arse- 
nic and molybdic acids are generally separated by super- 
saturating the solution with ammonia and adding 
magnesia mixture. The precipitate of ammonium-mag- 
nesium arseniate thus obtained is allowed to stand for 
forty-eight hours, and filtered, dissolved in nitric acid, 
again precipitated with ammonia, and converted into 
magnesium pyroarseniate. 

To the colleSed nitrates are added ammonium sulphide 
and sulphur, and the molybdenum sulphide precipitated 
by acid is converted into disulphide or metal by redudlion 
in a current of hydrogen. 

Though this method, on account of the ready entrance 
of molybdic acid into the double magnesium salt, does 
not give the most accurate results, it is still preferable to 
an indireA method in which both acids are precipitated 
together as mercury salts and ignited in a current of hy- 
drogen. The arsenic then escapes and the molybdic acid 
is reduced to metal, but a part of the molybdenum is apt 
to be volatilised, and, on the other hand, its complete re- 
dudion is difficult to effed. 

The authors* experiments were made with ammonium 
paramolybdate, three times re-crystallised, containing 
8z'55 per cent M0O3. 

This salt, on distillation with anhydrous methylic alco- 
hol and hydrochloric acid, behaves similarly to ammonium 
vanadate, but an addition of water is here sufficient to 
prevent molybdenum from passing over. 

For the management of the distillation everything 
holds good which has been said concerning vanadic acid. 
The determination of the molybdic acid in the residue is 
effe^ed in the manner described for vanadic acid. But 
the temperature must not be raised to redness. Hence 
the residue of evaporation is dissolved in ammonia and 
filtered into the platinum capsule, in order to remove the 
carbonaceous matter derived from the alcohol. 

V. Determination of Arsenic Acid and Tungstic Acid, 
The separation of arsenic acid from tungstic acid in- 
volves the greatest difficulties, as the former cannot be 



entirely removed by ordinary precipitants, nor even by 
sulphuretted hydrogen under pressure. 

It is best to follow Kohmann*s diredions. boiling the 
salt in question for half an hour with the double calcuJited 
weight of soda-lye, in order to split up the two compo- 
nents, and then with twice as much ammonium chloride 
as is necessary to combine with the alkali present ; ^ vol. 
of ammonia and magnesia mixture are added : the natx- 
ture is filtered after the lapse of two hours, washed with 
a mixture of ammonia and ammonium nitrate, and the 
precipitation is several times repeated. Certainly the 
total quantity of the tungstic acid can scarcely be sepa- 
rated from the ammonium-magnesium arseniate. 

The coUeded filtrates are evaporated down with hydro- 
chloric acid when the quantity of magnesium salt has a 
very disturbing effeA. 

We succeeded in the following manner in separatiog 
both acids with great accuracy : — 

The principle of the method is that we determine in 
one portion of the substance the joint weight of 
both acids, and in a second the weight of the tungstic 
acid alone, and calculate the arsenic acid from the 
difference. 

As we find, the determination of the total weight can 
be thus accurately effeded : — The aqueous solution of the 
arsenic tungstate is heated on the water-bath, and whilst 
diligently stirring a solution of mercurous nitrate is added 
until no further precipitation takes place, whereupon the 
free nitric acid is neutralised by pure mercuric oxide sus- 
pended in water. After heating the whole (still covered 
with a clock-glass) for twenty minutes on the water-hath, 
it is allowed to cool, the precipitate is filtered off, washed 
with water containing nitric acid, dried, removed from 
the filter as completely as possible, and the rest still ad- 
hering to the paper is dissolved into a platinum crucible 
with warm dilute nitric acid. After evaporating away 
the acid the bulk of the precipitate is introduced into the 
crucible, covered with a large quantity (15 to 20grms.) of 
weighed, anhydrous, normal sodium tungstate ; the cru- 
cible is filled with water and evaporated to dryness on the 
water-bath, whereby the precipitate is intimately pervaded 
by the sodium tungstate. 

The covered crucible is then gradually heated to 200° 
in the air-bath — whereby the rest of the water escapes 
— and cautiously ignited (under the draught-hood), first 
with a single burner, and then with a sixfold burner. A 
constant weight is obtained after a single ignition for half 
an hour. 

The filter, to which a small quantity of tungstic acid 
still adheres, is burnt separately. 

For determining tungstic acid alone, the precipitation 
and drying of the precipitate are effeAed exadly in the 
same manner, but, after its removal from the filter, the 
latter is burnt at once without a previous treatment with 
nitric acid ; the main quantity of the precipitate is added, 
and ignited at once with the addition of the normal 
sodium tungstate. 

The results obtained possets an exaditude which is not 
even remotely approached by any other method of deter- 
mination. The analyses are also convenient and expe- 
ditious in execution, and gain further in simplicity if, in 
determining the tungstic acid, we use the Gooch crucible 
and thus dispense with the incineration of the filter. 

The above method of the distillation of arsenic with 
methylic alcohol in hydrochloric acid is available also for 
the separation of arsenic from many other elements, 
especially from iron, cobalt, nickel, and copper, which it 
accompanies in numerous minerals. — Berichte, xxviii., p. 

Synthesis by means of Cyanacetic Ether. — T. 
Klobb.— In this manner the author has obtained the pbeo- 
acylcyanacetic and phenacylacetic acids and the methyl- 
methyl phenacylcyanacetate and the analogous ethyl 
compound. He has also studied the aAion of cbloracetone 
upon sodium cyanacetic tthtu-^Comptes Rendus, No. 14. 



Ckkmical Nbws, I 
Oa. x8. 1895. f 



Th$ Science of Examining. 



193 



THE SCIENCE OF EXAMINING. 
By PETER T. AUSTEN, Ph.D., F.C.S. 

Much severe criticism is being direded against examina- 
tions and much of it is timely and fully deserved. And 
yet when the criticisms are carefully considered they ap- 
pear to be direded not so much against examinations as 
a method in education as against certain forms of exam- 
inations which are very prevalent and which certainly do 
not show anything more than evanescent memorisation, 
adroitness, or trickiness on the part of the student. No 
one will deny, however, that much of adual life is a kind 
of examination, and that we are being continually pressed 
to solve problems of all kinds, apply knowledge, and in 
general to a^, and that on the success of our efforts will 
depend the positions we will attain, or at least maintain. 
There seems to be no reason why examinations should 
not be made an extremely important part of education, 
instead of being, as I fear they often are, an unmitigated 
nuisance to both student and teacher, a bone for the peda- 
gogical critics continually to snarl over, and, when all is 
done, to be of no real use to either teacher or student, 
and to show nothing as to the real nature of the teaching 
done and the mental development of the student. 

For the teacher who teaches from love of teaching, and 
who knows that successful teaching calls for the applica- 
tion of psychological principles far more than is generally 
supposed, there is a peculiar fascination in an examina- 
tion paper. An examination may be made a test of the 
contents, capacity, quality, and adion of a mind under 
defined conditions; but the paper must be a good one; 
I do not refer to the work of an inexperienced hand. The 
idea seems to be prevalent that anyone can write an ex- 
amination paper. This is a great mistake. The elabora- 
tion of a paper that will really test not only the contents 
of the mind, but also its different fundions as developed 
by a particular study under the guidance of a particular 
teacher, requires experience and ability. It is true that 
m man may be a good teacher and a poor examiner, but 
this usually arises from a lack of attention to the science 
and art of examining. My experience in this branch of 
pedagogical science leads me to believe that there are not 
very many really good examiners, and that the average 
examinations do not test the minds of the students as 
they ought to be tested. The average examination calls 
mainly for an exercise of memory, and for some proof that 
the student understands the matter he has studied. No 
man values the faculty of memory more highly than I do, 
or requires a better understanding of a given subjed. But 
memory and mere understanding are only the foundations 
of education. More than this is called for. Some exam- 
inations require skill in observation, others accurate 
definition ; while others bristle with problems. Some call 
for knowledge in which the teacher is weak. Almost 
every pedagogic earmark may be found in examination 
papers, but rarely is the paper construAed on such a plan 
that it tests not only the quality and- quantity of know- 
ledge in the mind, but also the various workings of the 
mind, and ascertains what the mind can do when set in 
aAion by the particular subjed. 

In my own speciality of chemistry there is an excellent 
opportunity for examination papers which may test the 
mind qualitatively and quantitatively, and probe both 
absorptive and produAive powers. I have always taken 
a great interest in working out examination papers and 
in studying the minds as they appear in the answers. I 
am accustomed to work out questions under various heads. 
The following example will serve to indicate my meaning, 
and may also encourage others to experiment in examina- 
tional science ; and I think that the method will be found 
so interesting that the investigation will not be hastily 
dropped. I should add that in the examination paper as 
givtn to the students the questions are mixed up, so that 
the classifications given as follows do not appear. 



Questions for Ttsting : — 

Memory. — (i) Give a brief history of oxygen. (2) Out- 
line the theory of phlogiston. (3) What are *• copperas," 
••bluestone,*'"t!ncal"? 

Accuracy of Definition. — (4) State concisely the laws of 
Dalton, Charles, Mariotte, and Avogadro. (5) Define a 
mechanical mixture. (6) Define an element. 

Observation of Experimentally Demonstrated Facts,* — 
(7) Describe and sketch an apparatus for producing 
acetylene from calcium carbide, and explain the working 
of it. (8) Describe and sketch the combustion of nitric 
acid in iodohydric acid. 

Accuracy of Detail.^(g) Explain with the aid of 
sketches the redudion of hot cupric oxide by hydrogen, 
heating the oxide in a combustion- furnace and preparing 
the hydrogen in a Kipp generator.! (zo) Make a sketch of 
a seaion of Pepy gasometer, and explain how the ap* 
paratus works. 

Acquaintance with the Properties of Matter, — (11) De- 
scribe the properties and chemical behaviour of nitrogen, 
sulphur, zinc, silica, and iodine. 

Retention of Oral Instruction, — (12) Explain the con- 
tamination of water by sewage. (13) Describe the pro- 
cess for making open hearth steel. 

The Faculty of Comparison.^(i^) State similarities and 
differences between the properties of oxygen and hydro- 
gen. (15) What substances resemble lead sulphide in 
colour and solubility in nitric acid ? 

Lucidity of Statement, — (16) Describe minutely and 
without sketches the apparatus and method of preparing 
phosphine. (17) Prove by analysis of stibine by volume 
that the molecule of antimony is tetratomic. 

Recognition of Substances, — (x8) A yellowish green gas 
with a suffocatmg odour. What may it be f (19) A 
colourless gas, very soluble in water, gives white fumes 
with hydrochloric acid. What may it be ? (20) A white 
powder, insoluble in water; heated with concentrated 
nitric acid it evolves red fumes and yields a solution, 
which, when excess of acid is evaporated off, and it is 
diluted with water, yields a precipitate which is insoluble 
in concentrated nitric acid. What may this white sub- 
stance be ? (21) A chemist wishes to fill a jar with red 
liquid. What substance may he use ? 

The Ability to Observe, -- {22) Give four examples of 
chemical change which you observe in this room. (23) 
Describe an ordinary red building-brick, stating dimen- 
sions and properties of surface, weight, fradure, &c. 
(24) Water expands 00 freezing. Give five examples of 
results caused by this expansion which you have person- 
ally observed. 

The Application of Facts to Proofs, — (25) Prove that 
water is formed by the combustion of a kerosene lamp. 
(26) Prove that hydrogen sulphide contains sulphur. 

The Interpretation of Phenomena, — (27) A piece of 
white paper on being held for an instant in the flame of 
a candle and at right angles to it, a black ring is formed 
on the paper. Explain what the ring indicates, and how 
the particles of carbon are formed, and why they are de- 
posited on the paper. (28) A Roman candle on being 
ignited and then thrust under water continues to burn. 
How can this be accounted for ? (29) Why cannot fish 
live in lakes on the tops of very high mountains ?| 

The Application of Knowledge. — (30) The iodine falls 
into the sand box. How can the iodine and sand be sepa- 
rated ? (31) A mixture consists of barium carbonate, 
sodium sulphate, and sulphur. How can they be sepa- 
rated ? (32) A manufadurer has a waste produa con- 
sisting of a liquid containing 40 percent of sulphuric acid, 
10 per cent sodium sulphate, and 5 per cent ferric sul- 
phate. How can he treat it so as to convert it into other 
produAs that have commercial value ? 

* Given ID leAtires and not in text- book, 
f Given in text-book and demonstrated in leAure. 
} Compare London University Matricnlation Examiaatioos, 
Stoker and Hooper, p. 31. Q. 6. 



194 



The Science oj Examining. 



I Cbsmical Rbws, 
I 0&. 18, 1895. 



Dectptivi or MisUading Qtffx^ioni.— (33) Dilute sul- 
phuric acid ia poured upon zinc. A gas with a slight 
oluish* colour is evolved, which burns with a red* flame. 
What is it ? (34) Chlorine gas is colledled in a jar over 
mercuryt in the usual manner. It is then brought into a 
eudiometer, mixed with twicej its volume of hydrogen, 
and exploded. How many volumes of hydrochloric acid 
gas will be produced ? 

The Imagination. — (35) Filthy water of the gutter, 
warmed by the sun*s rays, escapes from a foul environ- 
ment, and, condensing, sparkles like diamonds on the 
f>etal of the violet. Use this as basis for an allegory in 
ife. 

These questions do not by any means represent all the 
possible divisions of mental adion, and I have purposely 
avoided those of a very technical nature, most of which, 
however, would fall under the heads given ; but they will 
serve to indicate what opportunities there are to construd 
examination papers that shall test a student's knowledge 
and the working of his mind. It may be urged against 
the questions I have given that several of them might fall 
as well under one head as another, or that a few more 
elaborate questions could be made out and each question 
marked under the several beads. My experience, how- 
ever, has not been that the real ends are best attained in 
this way. The question that is distinguished by its defi- 
nite nature and objed gets a clearer answer and gives a 
more tatisfadory insight into the student's mental equip- 
ment and a^ion than a long or complicated one. If, 
after teaching a student a subjea for a certain time, an ex- 
amination shows that he can bring forth nothing more than 
that which has been put into him, it may be inferred either 
that the teacher is incomptent, or that the student is in- 
telleAually deficient; assuming, of course, that the system 
in the particular institution permits the teacher to do his 
best, does not assign him more pupils than one man can 
teach, and requires the student to do the work assigned 
to him. In such case I think that the fault usually lies 
with the teacher. Still I admit that there are institutions 
in which educational work of a high pedagogical order is 
impossible, and mind development, as distinguished from 
mind cramming, is out of the question. In such a case 
students are produced who are saturated with knowledge, 
but who are incapable of utilising it. Like water-logged 
vessels they roll about aimlessly, and are unable even to 
keep out of the way of craft which are taking the 
fullest advantage of wind and tide. In such an institution 
the earnest teacher, when he fails, deserves sympathy 
more than blame. 

The results of examinations, conduced on some plan 
like the one I have attempted to describe, are very inte- 
resting. Such examination papers are far more difiScult 
to write than the calls for mere memorisation that are so 
frequently made on the student, and which a hasty cram 
will enable a fairly bright candidate to pass. The 
answers are more difficult to rate ; and often an attempt 
to mark them according to the usual rules is unsatisfac- 
tory. It is quite easy to assign a mark to the amount 
that a student knows, or even to discriminate as to the 
quality of his knowledge. To assign a figure to his 
ability to apply this knowledge, to originate, to create, to 
a6l under its instigation, is more difficult ; yet it can be 
done with a fair degree of success. 

It must always be borne in mind that a man's value in 
this life does not depend merely on what he knows, but 
upon what he can do. Cateris paribus^ the more he 
knows, the more he should be able to do ; for so much 
the greater should be the incentive, if the knowledge 
imparted to him ads on him as it should. Until tech- 
nical education was introduced, this fad was not well 
understood, and it is still far from appreciated in many 
schools. 

For instance : A shows in his paper an encyclopaedic 

* Coloorleii. 

t Chlorine cannot be colleded over mercury. 

X Once. 



knowledge. In his answer to Q. 11 h6 recites with great 
precision the properties of silica and iodine. But he fails 
to answer Q. 30, which calls for a conclusion dependent 
upon this knowledge. He is like a recruit who has been 
given a gun, but has not been taught how to fire it off. 
Such a student demands the teacher's attention at once. 
His mental inadion is usually the result of poor teaching. 

It may not be amiss for me to say parenthetioUly 
here that teaching is the most difficult of all pro- 
fessions. It is not usually regarded so, but I believe 
that it is. Much of what is called teaching is nothing 
more than a kind of pumping. Knowledge is forced 
in through the most convenient intelledual orifice, a 
great deal being lost in transitu^ and not a little 
leaking out afterwards. The engorged recipient is like a 
boiler whose feed-pump is too big for it and will not cease 
pumping, but fills the boiler entirely full of water and 
leaves no space for steam ; whereon the engine slows 
down and stops, or throbs soggily with its cylinder filled 
with lukewarm water instead of hot expansive steam. 

Again, a student may fail in his attempts to state any- 
thing corredly or exadly ; but he fills pages with attempts 
to apply his knowledge, suggesting all sorts ot ideas and 
applications. Most of them may be impossible, some 
even ridiculous. But no matter, let the teacher take hold 
of this boy at once, for the mind of an Edison, a Siemens, 
or an Ericsson may be seeking nourishment and develop- 
ment. Happy is the teacher who can discern what mean 
the instindive strugglings of the embryonic master mind, 
and who can liberate it from the thraldom of routine — 
who can guide its first weak attempts to walk and climb, 
until it becomes hardy and venturesome, and fearlessly 
scales cliffs heretofore inaccessible : and so clambering by 
hitherto unknown ways to the peak discovers new fields 
for human adivity, and cuts a wide path by which thou- 
sands may enter and take possession. 

What man gets closer to the Creator than the teacher, 
who can discern and understand His idea as shown in the 
youth and who clears away the obstacles in the way of 
its development, nourishes it until it is strong and inde- 
pendent, and itself becomes creative ? Verily such m 
teacher has his reward. 

Examination papers construded on the basis I have 
suggested, viz., to test not only the knowledge possessed 
by the student, but also the working of his mind upon 
the particular subjed, will show more clearly the nature 
and condition of a mind than the daily recitation, because 
the case is more capable of systematic study and can be 
made to cover larger fields of mental adivity. While I do 
not intend to suggest that such examinations should re- 
place the regular recitation, I believe that they should be 
held frequently, and should serve a far wider purpose than 
that of merely noting the quantity of knowledge absorbed 
by the mind. Such an examination is not a mere matter 
of testing and registering; it is a creative exercise of the 
mind. — Science^ 



THE PRECIPITATION AND GRAVIMETRIC 
DETERMINATION OF CARBON DIOXIDE.' 
By F. A. QOOCH and I. K. PHELFS. 

The method upon which reliance is most confidently 
placed for the determination of carbon dioxide in solid 
carbonates, involving as it does the liberation of that gas 
by the adtion of a strong acid and its absorption in 
weighed potash bulbs, demands as conditions of the at- 
tainment of good results the careful observance of precau- 
tions and the expenditure of much time and attention. 
In the method described below we have sought to secure 
equal accuracy with greater economy of time and care. 



* Contributions from the Kent Chemical Laboratoty of Yale CoU 
lege. Prom the A mtrican jfoumal 0/ Science^ vol. 1., Aug., 1895. 



CBBMICAL NBWSt I 

oa. x8, i8g5. r 



Precipitation and Determination of Carbon Dioxide. 



195 



Oar plan is to effedi the rapid absorption of the carbon 
dioxide, evolved by the aAion of acids upon carbonates, 
in barium hydroxide contained in a specially devised appara- 
tus, to filter and wash the precipitated barium carbonate 
under a protediog layer of xylene, to dissolve in hydro- 
chloric acid the washed carbonate upon the filter or 
adhering to the receiver, to convert the barium chloride 
thus obtained into the form of the sulphate, and from the 
weight of the last to calculate the carbon dioxide origin- 
ally liberated by acid from the carbonate. 

The apparatus which we use, and which is shown in 
the figure, consists of a flask for the evolution of the car- 
bon dioxide, properly conne^ed with a receiver in which 
the gas is retained until absorption is perfeA. It is a 
form of a similar device employed by one of us (^m«r. 
cium. y<nlm,t t., 450) for the absorption of ammonia in 
hydrochloric acid and the complete retention of the am- 
monium salt thus formed, but so modified as to avoid the 
danger of diffusion of carbon dioxide through the rubber 
balloon — a source of error which we have foun(^by experi- 
ment to be considerable when large amounts of the gas 
are handled. 




The evolution flask (p) has a capacity of about 50 cm.", 
and is fitted with a rubber stopper through which passes 
a tube (a) wide enough (about 0*7 cm. in interior 
diameter) to prevent the formation of bubbles, and ex- 
panded just above the stopper to a small bulb. The ab- 
sorption cylinder consists of a wide glass tube (c), fitted 
at either end with a rubber stopper. The stopper at the 
lower end of the cylinder, placed vertically, carries a short 
tube, about 1*5 cm. in diameter, to which is secured a 
smaller rubber balloon. The cylinder and balloon together 
hold about 100 cm.". The upper stopper is perforated 
with two holes, through one of which passes the tube of 
a glass stopcock, while through the other hole passes a 
long tube reaching to the interior of the balloon and pro- 
vided with a valve (v) — preferably a modified Bunsen 
valve, of the pattern recently devised by Kreider {Am, 
Journ. Sci„ 1., p. 13a). 

In using this apparatus a saturated solution of barium 
hydroxide (which is made hot, filtered into a syphon- 
bottle, and preserved from atmospheric a&ion by a floating 
layer of kerosene) is introduced by pressure upon the air 
in the syphon-bottle or by sudion applied to the stopcock 
of the cylinder. Such a solution contains about 5 per 
cent of its weight of the hydroxide, and we find it best 
to use in every case an amount at least a fourth in excess 
of the quantity theoretically required to absorb the carbon 



dioxide, and to fill the cylinder and balloon nearly full of 
liquid. The carbonate is weighed, introduced into the 
flask, and washed down with 15 or 20 cc of boiled water, 
which is prote^ed in the wash-bottle from carbon dioxide 
in the breath by a balloon attached to the inlet tube. A 
small tube, holding enough hydrochloric acid to effe^ the 
decomposition of the carbonate to be analysed, is placed 
in upright position in the evolution flask. The stopper 
is inserted in the flask, and connexions are made as 
shown in the figure ; the little tube containing the acid it 
overturned by inclining the flask ; the acid mixes with 
the water, and effervescence begins. Heat is applied, and 
the liquid in the flask is boiled until that in the cylinder 
is heated by the steam nearly to the boiling-point, in order 
that the precipitated barium carbonate may become as 
granular as possible. The carbon dioxide evolved and 
the air in the flask are transferred in the process to the 
absorption cylinder, the valve serving to prevent the back 
flow of the liquid, while the balloon expands to give room 
to the air and condensed steam. When the boiling is 
done the flask and tube are disconneded at the rubber 
joint, the cylinder is shaken to insure the absorption of 
the carbon dioxide, and the liquid carrying the greater 
part of the precipitate is transferred through the stopcock 
to a filter carefully fitted to its funnel, moistened with 
water, and containing about 5 cm.' of xylene (which we 
found to be preferable to benzene, kerosene, or amyl alco- 
hol), the fundion of which is to rise to the surface when 
the aqueous solution is added, so as to proted the barium 
hydroxide from the adion of the carbon dioxide of the 
air. By manipulating the balloon and the stopcock (to 
which a little funnel maybe attached by a piece of rubber 
tubing for convenience in introducing wash-water) the 
cylinder may be emptied and washed out with hot boiled 
water, though, of course, a very considerable portion 
of the precipitate remains adhering to the walls of the 
absorption apparatus. 

We prefer to prepare the filter for use with the sudion 
pump, but in the early stages of filtration and washing 
very little sudion should be applied. When the barium 
hydroxide has been nearly washed out of the precipitate, 
the xylene is dissolved in a little hot alcohol, the suAion 
is applied, and the washing is completed with hot water. 
The emulsion of xylene and water found in the filtrate is 
readily cleared up by alcohol. Finally, the barium car- 
bonate in the absorption appr.ratas and upon the filter is 
dissolved in hydrochloric acid and precipitated in hot so- 
lution by sulphuric acid ; the resulting barium sulphate is 
filtered, washed, and ignited upon asl^stos in a perforated 
crucible, and from its weight the carbon dioxide which 
originally precipitated the barium, now in the form of 
the sulphate, is calculated. The results of a series of 
determinations made in this manner are recorded in the 
following table : — 

(Ba- 137*43, S«3a'o6, 0»i6, C = i2.) 







CO, 






CaCO, 


BaSO« 


aAoally 


CO, 


Error in 


Uken. 


found. 


present. 


calcnlated. 


CO.. 


Gnn. 


Grm. 


Grm. 


Gim. 


Grm. 


0*0500 


O'llSo 


0*0220 


0*0222 


0*0002 -(- 


0*0500 


OI183 


0*0220 


0*0223 


0*0003 + 


0*1000 


0*2329 


0*0440 


0*0439 


O'OOOI- 


IZOOO 


0*2347 


0*0440 


0*0442 


O'O0O2-(- 


0*2000 


0*4660 


0*0880 


0*0878 


0*0002- 


0*2000 


0*4653 


0*0880 


0*0876 


00004- 


0*5000 


I* 1650 


0*2200 


0*2196 


00004- 


0*5000 


I 1657 


0*2200 


0*2197 


0*0003 - 


I'OOOO 


23323 


0*4400 


0*4396 


00004- 


zoooo 


2-3309 


0*4400 


0-4394 


0*0006- 



Various modifications of method and manipulation 
were put to the test of experiment, but the process which 
we have described has proved on the whole the most 
satitfaAory. It is fairly rapid and accurate. 



196 



Vapour-tensions of Mixtures of Volatile Liquids. 



i Cbbmical Nswb, 
I Oa. x8, 1895. 



ON THE VAPOUR.TENSIONS OF MIXTURES 
OF VOLATILE LIQUIDS.* 

By C. E. LINBBARGER. 
(GoDtinaed from p. 184). 

Choici and Purification of Liquids, 
As stated previously, the liquids employed in the course 
of this investigation were those recognised to be stridtly 
normal ; and of those only such were chosen as can be 
gotten in a state of great purity. The only associated 
liquid taken was acetic acid, whose degree of association 
as well as whose physical properties are to a certain ex- 
tent known. 

An associated liquid was investigated for the purpose 
of applying the regularities and ** normalities " discovered 
in mixture of normal liquids to mixtures of a normal 
Siquid with an associated liquid. Great pains were taken 
to purify the liquids in the highest possible degree, it 
being the testimony of all those who have occupied them- 
selves with experimental work on the vapour-tensions of 
liquids that even very slight impurities have a remark- 
ably disturbing effedl upon the accuracy of results ; this 
is especially the case in results obtained by the static 
method ; in the method employed by me, the influence 
of a slight amount of impurity is not so marked ; still, 
for all that, it has been thought best to employ such 
material as had been most thoroughly purified. 

In order that the readers of this paper may judge for 
themselves the degree of purity of the liquids examined, 
a somewhat detailed account of the method of purification 
of each liquid is given together with a statement of cer- 
tain charadteristic physical properties of each. All of 
the liquids, it may be stated beforehand, were bought as 
chemically pure from the dealers (Poulenc Fr^res, Paris, 
and Billault, Paris), and at least one pound — generally 
two or three pounds — subje^ed to the purifying opera- 
tions. 

BtnMine, — Nearly three pounds of benaene— labelled 
chemically pure and free from thiophene — were treated a 
half-dozen times with sulphuric acid to remove last traces 
of the sulphur compound. The liquid was then repeatedly 
fradionally crystallised until about a pound was obtained 
melting at 5 3^ This purified produdl when partially 
solidified showed, no matter what the proportion of 
liquid and solid was, the same melting point. The whole 
was then distilled over a few pieces of sodium, no varia- 
tion from the boiling-point 80* i** under a pressure of 756 
m.m. of mercury being observed. Its specific gravity at 
25° referred to water at the same temperature was found 
to be 0*8766x1. 

Toluene.—Oi the quantity of toluene taken for purifica- 
tion (about two pounds) more than four-fifths distilled at 
109*8° to xzo-z^ an indication that the commercial article 
was nearly pure. After a couple of distillations over a 
little sodium, more than a pound was obtained boiling 
constantly at zio'i** under a pressure of 758 m.m. of mer- 
cury. Its density at 25° referred to water at 25*0° was 
ascertained to be 0-86288. 

MonochlorbenMtnt. — A couple of pounds of monochlor- 
benzene were repeatedly distilled in fra^ions until a con- 
stant boiling product resulted. About three-quarters of 
a pound were obtained, boiling at 131*8° to 131*9° under 
a pressure of 757 m.m. of mercury, and having a density 
of 25*0** (referred to water at same temperature) of 
1*10362. 

MonohromhinMem. — Nearly a pound of brombenzene 
was fra6ionally distilled until a distillate was obtained 
boiling between nairow limits. About 150 grms. of the 
produd, boiling at X54*3° to 154*5° under a pressure of 
761 m.m. of mercury were obtained. The density at 25* 
referred to water at 25*0° was 1*49852. 

Nitrobensem, — The commercial article was repeatedly 



crystallised until an almost colourless liquid was obtained, 
which, when solidified, showed the same temperature 
during the re-melting. It possessed a melting-point of 
3*6°, and its density was z'202oz — 



(S)- 



* Abridged from the Joufnal of tht American Chemical Society ^ 
vol. svli., No. 8, Augait, 1895. 



Chloroform. — About two pounds of ** chloroform 
anesth^tique ** of commerce were washed a dozen timea 
with water, dried thoroughly by means of fused calcium 
chloride, and distilled. The larger distillate boiled at 
60*8° to 6i'o' under a pressure of 751 m.m. of mercury ; 
and, finally, nearly a pound was obtained boiling at 60*9* 
under a pressure of 755 m.m. of mercury. 

Carbon Tetrachloride, ^Tv/o pounds were washed with 
water, and thoroughly dried by means of concentrated 
sulphuric acid. The produA was then reAified, and 
nearly a pound boiling throughout the operation at 76*6^ 
under a pressure of 756 m.m. of mercury uken for the 
preparation of the mixtures. The specific gravity of this 
produdi at 25*0° referred to water at the same tempera- 
ture was 1*58828. 

Acetic Acid, — Two pounds of glacial acetic acid were 
repeatedly fra&ionally crystallised until a portion 
melting at 16*7° was obtained. The bottle containing it, 
as well as the mixtures made from it, were kept under an 
air-tight bell-jar by the side of very strong sulphuric acid. 

Preparation of the Mixtures, 

The mixtures were prepared by weighing out to a milli- 
grm. on a balance turning with a tenth m.grm.the liquids 
in a flask ; the corked flask was tared, the less volatile 
liquid poured in and weighed, and then the more volatile. 
As from 40 to 100 grms. of the mixture were weighed out, 
the composition of the mixture was thus known to a ten- 
thousandth at least. The mixtures were preserved in 
bottles or flasks fitted with the finest corks, and kept in 
a dry cool dark closet. As, almost invariably, the neces- 
sary' vapour-tensions of a liquid were made immediately 
after its preparation, no change of concentration occurred 
even with the most volatile liquids employed. 

In the case of some of the mixtures of benzene and 
carbon tetrachloride, the residues of the investigated mix- 
tures were united, and the amount of chlorine in the re- 
sulting mixture determined according to Carius's method. 

The mixtures of benzene or toluene with acetic acid had 
their concentration controlled by an analysis. 5 to xo 
c.c. of the mixture were carefully weighed out in a glass- 
stoppered flask, water was added, which took pra^cally 
all the acetic acid from the benzene, and then standard- 
ised baryta-water run in to point of neutralisation. In no 
case did the analvsis give results sensibly different from 
those calculated from the dired weighings. 
(To be continned). 



NOTICES OF BOOKS. 

Eiements of Modem Chemistry. By Charles Aoolphe 
WuRTZ. Fifth American Edition, Revised and En- 
larged. By W. H. Greene, M.D., and H. F. Keller, 
Ph.D. (Strassburg). With a Portrait of the Author and 
numerous Illustrations. Philadelphia and London : 
J. B. Lippincott Company. 1895. ^P* 808. 
In examining this work, we have firstly to consider the 
original as it issued from the pen of the late illustrious 
Prof. Wurtz, and secondly the version executed by 
Messrs. Greene and Keller. 

The original must be recognised as an admirable sum- 
mary of chemical science down to the death of the author 
(1884). Though it was more especially adapted to the 
requirements of medical students, it may be recommended 
as one of the best elementary works on chemistry of a 



CHByicAL Nbws, 1 

oa. i8, 1895. I 



Chemical Nottces from Foreign Sources. 



197 



moderate compass. Professor Wurtz does not discuss the 
nature and possible origin of the elements ; he gives them 
his provisional acceptance without speculating on their 
possible ultimate nature. Hence Prout's hypothesis is 
Ignored, and the periodic classification of the elements 
with its consequences is ascribed exclusively to Mendeleeff, 
without any reference to Lothar Meyer or Newlands. 

At many discoveries of the highest importance have 
been effeded within the last twelve years, the task of the 
translators has not been easy. They have added notices 
of the isolation of fluorine, of argon and helium, of hydra- 
sine, hydrazoic acid, and their principal derivatives, of 
stereoisomerism, and of some of the more recent dis- 
coveries in the chemistry of the rare earths. The locali- 
ties occasionally given, «.^., for the occurrence of mineral 
waters, are almost exclusively American and little known 
to European readers. The language employed is not in 
all cases idiomatic English as spoken to the east of the 
Atlantic, but a moment's reflexion enables the reader to 
deteA the meaning. 

The work before us deserves an honourable position in 
the library of the chemical student. 



Oh Dangers to Mtn Bmphyid in Chtmical Workst Means 
of Preventing Accidents^ and Conditions of Work, A 
Critical Discussion of English and German Industrial 
Relations, occasioned by the English Parliamentary 
Report of 1893. ('* Ueber Gefahren fiir die Arbeiter in 
Chemischen Fabriken, Unfallsverhiitungsmittel und 
Arbeitsbedingungen Eine durch den Englischen Parla- 
ments bericht von 1893, veranlasste kritische 
Besprechung Englischer und Deutscher Industrie 
verhaltnisse "). By Konrod W. Jurxsch, Doceot at 
the Royal Technical High School of Beriio. beriin : 
R. Gaerntner. 1895. 
The report presented by the Chemical Works Committee 
of Enquiry of 1893 is» ^^ course, well known in this 
country. Still, it is interesting to see how its conclusions 
mnd recommendations appear to a foreigner who has the 
advantage of personal acquaintance with the heavy che- 
mical trades, and has resided for some time at St. 
Helens and Widnes. The Committee of Inquiry, unlike 
the late Rivers* Pollution Commission, had the advantage 
of including two physicians, whose special reports on 
the physiological anions of the conditions to which the 
workmen are exposed are eminently judicious. 

As remedies for the effedis of chlorine and of corrosive 
gases, the men have recourse to brandy or whisky. Dr. 
Jurisch found that they were ignorant of the employment 
of ammoniacal vapours, and could not be taught to use 
them. The present writer has often found personally and 
observed on others much benefit from sips of the strongest 
vinegar or dilute acetic acid. That Dr. Jurisch is clusely 
acquainted with the effeds of irrespirable gases is proved 
by the fad that he advises men in such cases to retire 
slowly, taking only slight superficial breaths of air until 
reaching a purer atmosphere. To take a full breath is 
exceedingly hazardous and might conceivably be fatal. 
The fad that certain precautions m vogue on the 
Continent are neither pradised in English chemical 
works nor proposed by the Commissioners, Dr. Jurisch 
ascribes to the different conditions of work, and, above 
all, to the carelessness of the men and their aversion to be 
taught anything. He points out that the administration 
of ammonia to a man half suff^ocated with chlorine unless 
effedcd with judicious care may increase the mischief. 

To a careful sober man the manufadure of chloride of 
lime presents far less dangers than has been represented 
by sensational writers. It is shown that relatively 
shallow layers of lime in the chloride chambers, which do 
not require to be turned over, are in reality, preferable, as 
well from an industrial as from a hygienic point of view. 

Small quantities of hydrochloric acid in the air do not 
interfere with respiration, improve the appetite, and oc- 
casion no inconvenience beyond ** setting the teeth on 



edge.'* Vapours of sulphuric acid are more pernicious. 
It is remarked that boys under eighteen years of age are 
not employed in the manufadure of chloride of lime and 
of sulphuric acid, and that women are altogether ex- 
cluded. 

Caustic soda presents its dangers ; a fall into the melting- 
pans is almost inevitably fatal. Hence it would be wdl 
if care were taken in British works, as in those of France 
and Germany, to exclude any man from work in this 
department who is not sober. 

It is here remarked that in Continental works the mix- 
ture of lime-water and linseed oil, invaluable as a remedy 
for burns, is kept ready for use on a large scale. In 
England and Scotland it has been in use to our certain 
knowledge since 1857, under the name " Carron oil." 
The Commission did not think it necessary to mention so 
well known a remedy. 

The use of lead acetate as an application to the eyes 
in case of a spirt of acid or alkali dates back to the same 
year, and that at a works in Widnes which certainly made 
no speciality of care for the sanitary well-being of the 
workmen. 

This Report, both in its original form and in the 
German annotated and critical version, will be of great 
service in leading to hygienic improvements which can 
be introduced without interference with the manufadure. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NoTB.^AU degrees of temperature art Ctatigradt onless otherwiss 
expreMed. 



Comptes Rendus Htbdotncuiaires des Heanc^St de VAcademie 
des Sciences. Vol. cxxi., No. 14, September 30, 1895. 

The Death of Louis Pasteur.— A. Cornu, the Presi- 
dent, delivered an eloquent discourse on the eminent 
merits of the discoverer whom the world, and more especi- 
ally France, has just lost. 

Remarks on the Discourse of Lord Salisbury on 
the Present Limits of our Science. — Emile Blanchard. 
— In the shape of a notice of the Presidential Address 
delivered by the Marquis of Salisbury at the Oxford 
Meeting of the British Association (1894), M. Blanchard 
has repeated the threadbare challenge of the anti-evolu- 
tionists, that if anyone will show an instance of the trans- 
formation of a species he will confess himself mistaken I 
He knows perfedly well that his challenge presupposes 
the impossibility of a naturalist living and observing for a 
few thousand years. 

New Nitrogenous Manure: Calcium Cyanate. — 
Camille Faure. — The substance in question is calcium 
cyanate, Ca(CN0)3, hitherto a laboratory curiosity, 
but now promising to become an important substitute 
for nitrate of soda, and even containing a larger proportion 
of assimilable nitrogen. A mixture of limestone and coke 
is submitted to a preliminary temperature of 1500° in an 
eledric blast furnace, and is then superheated in the same 
furnace to 2500° in presence of a large excess of pure 
nitrogen, and finally to oxidation by means of air, the oxy- 
gen of which is retained by the produd, whilst the nitrogen 
conveys the heat due to the oxidation into the eledric 
chamber. The operation must be conduded in a large 
furnace, so that the calorific yield may be sufficiently 
economical. The assimilation of the nitrogen of this 
produd by vegetation does not appear to be doubtful. 

Conbtitution of the Acids produced in the Oxida- 
tion of loatflive Campholenic Acid. — A. B^hal.— The 
author claims the priority of the synthetic preparation of 
diroethylglutaric acid as against Dr. Tiemeni. 



igS 



Chemical Notices from Foreign Sources. 



I Crbmicai. Nsirtv 
t oa. x8. X895. 



Bulietin de la Sociiti Chimique dt Paris, 
Series 3, Vols, xiii.-xiv., No. 10, 1895. 

Tioaorial Properties of Glucina. — M. Prudhomme. 
The author explained the different tin^orial properties of 
sesquioxides and protoxides. The former do not become 
■aturated with alixarin in distilled water ; in order to form 
a solid lake they reouire the co-operation of lime. The 
■econd dye np equally well with or without lime. Glocina 
at regards dyeing behaves like a protoxide. 

AmmoDium Manganoas Phosphate, and its Use in 
the Volumetric Analysis of Phosphoric Acid.~MM. 
Lindemann and Motten. 

Preparation of Monomethylamine.~A. Brochet and 
R. Cambier. — The authors place 2 kilos, of commercial 
formic aldehyd in a three-litre flask, conneded to a good 
refrigerator by a Wurtz tube fitted with a thermometer, 
and X kilo, of ordinary crystalline sal-ammoniac. On 
heating gently the liquid becomes strongly acid and takes 
a yellow colour. At 40° there is produced a brisk ebulli- 
tion, when the heat is reduced. Methylal distils over in 
abundance. We then raise the temperature by degrees 
to 95°. The receiver is changed and the distillate con- 
tains 60 to 70 per cent of methylal. The solution is con- 
centrated until the excess of sal-ammoniac begins to pre- 
cipitate, and on refrigerating this salt is deposited almost 
entirely. It is drained by sudion ; the filtrate is a solu- 
tion of monomethylamine almost pure. 

Two Combinations of Mercuric Sulphate with 
Thiophene, allowing of the Determination of this 
Substance in Commercial Benzines.— G. Denig^s. — 
The author describes in detail the determination either 
in an aqueous or a methylic solution. 

Ammoniated Derivatives of Hexamethyltriamido- 
triphenylmethan, its Carbinol, and its Mixed Ethers. 
— A. Rosenstiehl. — This voluminous paper does not admit 
of a complete abstradion. We may see that experimental 
proof is given that the leucobases, the magentas, and the 
rosanilines contain amidic-groups with the same func- 
tions. All three are triamines of the same degree ; in all 
the three classes of compounds the three groups NHa 
fulfil the same fun^ions without a single rea^ion leading 
to the admission that one of them is retained in the mol. 
of any other bond than that which retains the atom of H 
which it replaces in the mol. of phenyl. 

The Question of Acid Magentas. — Maurice Prud- 
homme. — A polemical paper. The author considers 
that the conceptions on the nature of the acid magentas 
may thus be summarised : — x. The colouring and coloured 
matter exists as a neutral salt or an acid salt of the sul- 
phonated carbinol. a. The addition of a mineral acid to 
the salts of rosaniline liberates the latter, which is 
coloured. 

No. II. 

Researches on Manganese.— Charles Lepierre.— 
Already inserted. 

Hydrated Metallic Chlorides. A Reply to H. 
LescoBur. — Paul Sabatier. — A polemical paper. 

Composition of the Wines of Samoa used in the 
Manufadture of Vermuth.— P. Cazeneuve and M. 
Hugounenq.— A paper of no scientific interest. 

Present State of the Produdion and Consump- 
tion of Phosphates. — David Levat.— A statistical ac- 
count of the produaion of natural mineral phosphate in 
Florida, Carolina, Algeria, and Tunis, and of the phos- 
phatic slags obtained by the Gilchrist process. 



MEETINGS FOR^ THE WEEK. 

FaiDAT, 2Sth.^Phvsicftl, 5. '* The Radial Cursor," by F. W. Laa- 
cbester. " The Development of Arbitrary Fuoc- 
tiont," by Prof. Perry and Mr. Hunt. 



EaaATUM.— p. X85, col. x, line 31 from bottom, /or *' 0*47325 cc." read 
•* 0*47335 gnn.** 



J. & A. CHURCHILL, 
PU BLISHER S. 

PRACTICAL CHEMISTRY AND 

QUALITATIVE ANALYSIS : Specially adapted lor CoUegea 
and ScheolB. By FRANK CLOWES. D.Sc, Profesior of Cbe- 
mistry in University College, Nottingham. Sixth Bditioot with 
84 Engravings, Post 8vo, 8«. 64. 

ELEMENTARYQUALITATIVEANA- 



LYSIS ; suitable for Organised Science Schools. By FRANK 

- • ~ - — • in Un 

ige, Nottingham, and J. BERNARD COLEMAN, I 

the Chemical Department, South- West London Polytechnic 



CLOWES, D.Sc. Lond., Professor of Chemistry in Uni' 
'^ "LEI 



College, Nottingham, and J. BERNARD COLEMAN, Head of 
the Chemical Department, South- "- - ^ . . . 

With Engravings. Post 8vo, 2i. 6<1. 

BY THE SAME AUTHORS. 

QUANTITATIVE ANALYSIS: specially 

adapted for Colleges and Schools. Third Edition, with xo6 Bn- 
gravingSy Post 8vo, 9«. 

VALENTIN'S QUALITATIVE ANA- 
LYSIS. Edited by Dr. W. R. HODGKINSON. F.R.S.B., Pro- 
fessor of Chemistry and Physics in the Royal Military Academy 
and Artillery College, Woolwich. Eighth Edition, Revised and 
Enlarged, 84. td. 

BLOXAM'S CHEMISTRY, INOR- 

GANIC AND ORGANIC, with Eiperiments. Re-writtca smd 
Revised by JOHN MILLAR THOMSON, Piofeaaorof Chemia- 
try. King's College, London, and ARTHUR G. BLOXAM, 
Head of the Chemistry Department, The Goldsmiths' Institate, 
New Cross, London. Eighth Edition, with 281 Engravings, 8vo, 
x8x. &/. 

BLOXAM'S LABORATORY TEACH- 

ING; Or, Progressive Exercises in PraAical Chemistry. 
Edited by ARTHUR G. BLOXAM, Head of the Chemistry 
Department. The Goldsmiths' Institute, London. Sixth Editioo, 
Revised and much Enlarged, with 80 Woodcuts, Crown 8vo, 

CHEMISTRY OF URINE; a Pra<5lical 

Guide to the Analyticsl Examinations of Diabetic, Albamioooa, 
and Gouty Urine. By ALFRED H. ALLEN, F.I.C., F.C.S. 
With Engravings, 8vo, 71. 6<^. 



London : 
J. & A. CHURCHILL, xx, New Burlington Strbbt. 

SULPHUROUS ACID. 

SULPHITES AND BISULPHITE OF LIME. SODA, &c. 

HYDROGEN PEROXIDE, 10/30 vols. 

CARAMELS, Llqtild and SoUd. 

BENNETT d J EN NER^ Stratford, London. 



MICA 



Talapbooc 

F. WIGGINS & SONS. JSi.'^i^nSIc* Lcndoa. 
MICA MERCHANTS, ' 

Manufaetufifs of Hica Goods for EUctricai and ALL pmrpotn. 
Contractors to Her Majesty's Oovernment 



SILICATES OF SODA and POTASN. 

In THK STATtt OF SOLUDLB GLASS OR IN CONCINTEATBD 80LUT10H 

OLDEST AND MOST RELIABLE MAKB. 

FULL STRENGTH GUARANTEED. 

Soited for the Maoofaaure of Soap and other purposes. 

Supplied on best terms by 

WILLIAM OUS8AGB ft SONS, Ltd., Soap Works. Widnea. 

London Aobnts^COSTE & CO., i8 & 19, Water Laos, Tower 

Street, E.C., who hold stock ready for delivery. 



Water-Glass, or Soluble Silicates of Soda 
and Potash, in large or small quantities, and sltber solid 
or in solution, at ROBERT RUHNBY'S, Ardwick Cboflucnl 
Works* Manchester. 



Cbsmicjo. Niwb, I 
oa. as. 1895. I 



Observations by Aid 0/ the TensiometeK 



199 



THE CHEMICAL NEWS. 

Vol. LXXII., No. 1874. 



OBSERVATIONS BY AID OF THE 

TENSIOMETER. 

Br |. ALFRED WANKLYN and W. J. COOPER. 

Thb paper which one of as prepared for (but did not read 
at) the Ipswich Meeting of the British Association (see 
Chemical Nbws, vol. Ixxii., p. 164) mentions our Tensio- 
meter. 

We emploj two modifications of the instrument, viz., 
one modification designed for the measurement of tow 
tensioni , and another modification designed for compara- 
tively high tensions. 

The modification designed for low tensions is original 
only in some seemingly trifling deiails, which we hope to 
mention more particularly on another occasion. We con- 
fine ourselves at present to the publication of some of 
the earliest results which we have obtained. 

Eleven consecutive terms of the Russian series of 
hydrocarbons, to igjiich we have given the name kerose, 
as set forth in oumcent papers on this subjed, have been 
taken for investigation. Our results are as follows :— 

Tension oi the vaponr 
Name ol the evolved m vacuo at 15^ C. 

bydroGStboo hqoid. M .m. of mercnry . 

Kerose axiii • •• z'a 



nil. 
xxi. 

XX. 

xix. 
xviii. 
xvii. 
xvi. 

XV. 

xiv. 
xiii. 



35 
6*9 

8-9 
10*0 
14-8 
i8'0 
3ro 
48*0 
59-0 
82*0 



The first of these hydrocarbons boils under ordinary 
atmospheric pressure at 176^ C, and the last at 76" C. ; 
and it will be observed that the gradual drop in the boil- 
ing point is shadowed forth by a continual increase of the 
tension of the liquid at ordinary temperatures. 

We have also measured the tensions of valerianic acid, 
acetic acid, and formic acid at 1$" C. as follows :— 

M.m. of nercory. 
Valerianic acid • • • • . . 6*0 

Acetic acid •• 9'o 

Formic acid .. .. •• .. lo'o 

Now, valerianic acid has about the same boiling-point 
as Kerose xxiii., and acetic acid nearly the same boiling- 
point as Kerose xvii., and formic acid comes between 
kerose xv. and Kerose xvi. There is utter want of 
parallelism between the fatty acid and the hydrocarbon in 
the matter of tension at ordinary temperatures. 

Teoiiofl of add. Corresponding tension of kerose. 

6 ra 

9 x8*o 

zo 40*0 

The drop from the boiling-point of valerianic acid to the 
hoiling-point of formic acid is shadowed forth by the in- 
crease from 6 to zo. But among the keroses a like drop 
in boiling-point is indicated by the increase from z 2 to 
40*0. 

The first term in onr table of the eleven keroses has a 
tension of z*2 mm. at zs*" C. If we gradually raise the 
umperature, the tension will gradually increase, attaining 



to 80 m.m. at about 96" C. When any of these keroses 
attain to a tension of 80 m.m., we are able to describe the 
comparatively steep se^ion of the tension-curve with 
approximate accuracy. Given the point in temperature 
at which the tension attains to 80 m.m. we can name the 
boiling-point under ordinary atmospheric pressure. The 
rule is, add on 80° in the case of Kerose xxiii. ; add on 
nearly 60^ in the case of Kerose xiii., and add on inter- 
mediate numbers in the instance of the intermediate 
keroses. 



THE LATEST DISCIPLE OF HERMES ' 
TRISMEGISTUS. 
By H. CARRINGTON BOLTON. 

Thb persistence with which a belief in the transmutability 
of metals clings to common people in these days of universal 
education shows that there are still individuals in whom 
avarice linked with superstition are stronger characteristics 
than honesty in thought and a^ion. In France the pub- 
lication of alchemical processes continues, scarcely a 
twelve-month elapsing without an addition to thia litera- 
ture; in that country, too, as well as in England, 
claimants of the secrets of Hermes occasionally appear. 
Often their first appearance in public takes place in a 
police-court to answer charges of fraud, for the law does 
not recognise the veridity of alchemical professions. The 
case of the ingenious American who endeavoured to 
swindle the Bond Street jeweller a few years ago, by 
borrowing gold sovereigns with a promise to *' multiply ** 
them, is fresh in the minds of readers of the Chbmical 
News. 

In September of this year an extraordinary exhibition 
of faith in alchemy occurred in New York City, the details 
of which remind us of similar transaaions reported in the 
Middle Ages. 

The persons in this domestic drama are four in number 
— a small tradesman, Qustav Hammer by name, and his 
wife, who became the dupes of two conspirators na;ned 
Stanley Glass and Max Pearlman. In the spring of Z895 
Glass confided to Hammer that a friend of his possessed 
a wonderful secret which would make them all rich ; his 
friend, he explained, vras an alchemist, and with a little 
brass, some copper, and a few platinum filings, and the 
wonderful secret, he could procure any amount of gotd. 
These representations interested Hammer and his wife, 
who consented to go into the business. Soon after, Glass 
introduced his friend Pearlosan as the possessor of the 
Philosopher's Stone, and these two indttced Hammer to 
furnish the money accessary for an. experiment ; the latter 
gave the reputed alchemist 4.50 dols. for platinum and 
234 dols. for other materials. After some delays and 
procrastination on the part of Pearlman, the great work 
was undertaken in his house. ... 

The experiment was conduded in a aemi«dark room, 
and began at midnight. The metals were placed in a 
crucible over a very hot fire, and Pearlman stirred them 
with a rod, at the same time pouring in a white powder 
—the Philosopher's Stone. The heat was maintained for 
a long time until the metals fused. After cooling the 
crucible, Pearlman took out the alloy and gave it to 
Hammer, saying it was pure gold. The tradesman took 
the fused mass to an assayer, who informed him the lump 
contained z8 dols. worth of gold. 

So far this resembles a page from the career of 
Sendivogius, but the sequel is very different. Hammer, 
indignant at the swindle, sought relief in the courts, and 
on his representations the Grand Jury indiaed Stanley 
Glass and Max Pearlman. During the taking of testimony, 
it appeared that Mary Pearlman, the alchemist's wife, had 
sought to have the case dropped by offering various sums 
of money — beginning with 60 dols. and rising to zoo dols. 
This was corroborated by Mrs. Louisa Hammer. 



200 



The Period-Table. 



Oft.^iig$. 



At tlM Ust accoonu, GUtt had been arretted, but 
PMrlman coold not be found. Verily, the good old timet 
of Ca g i i oet f o have departed I 



QUANTITATIVE ANALYSIS BY MEANS OP 
ELECTROLYSIS.* 

A PKBLnmiAKT report was fnmiahed by the Committee 
fa^rear in which the contemplated plan of work was oat- 

The bibliography of the tobjea hat been completed and 
is appended. 

The experimental work hat been carefoUy organited, 
and the retolu on the determination of btamnth and of 
tin are nearly complete. Other work it in progrett, bat 
the Committee prefer to hold overthete retolu until next 
year in order that they may be added to and may include 
mcthodt of teparation of tome of the metalt. 

Contiderable attention hat been given to the choice 
and arrangement of the special apparatat required. A 
detailed description of tome of the arrangemenu adopted 
will be given in the next report. 

At the bibliography it completed, the Committee pro- 
pose to devote tMir attention daring the coming year 
exchitively to experimental enqoiriet. 

Bibliography on Methods of QuantitaHvi Analysis by 

waans of BUctrolysis, 
The bibliography has been compiled from the following 
joomalt, and is complete np to the end of 1894 :~ 

Period 
JonnMl. abttraaed. AbbrevUtion. 

I. Joomal of the Chemical 

Society Z847-1894 J. Chem. 80c. 

2* Joamal of the Society 

of Chemical Indottry Z882-X894 J. Soc Chem. 

Ind. 
3. Chemical Newt • • • • z86o>z894 Chem. Newt. 
4* American Chemical Joar« 

ntl 1878-1894 Amer.Chem. J. 

5* Journal of Analytical and 

Applied Cbemittry.. 1887-X894 J. Analyt. and 

App. Chem. 

6. Joamal of the American 

Chemical Society •• 1879-1894 J. Amer.Chem. 

Soc 

7. Zeitschrift f&r Analyt- 

ischeChemie •• .. 1862-1894 Zeitt. anal. 

Chem. 

8. Berichte der Deattchen 

chemitchen Qetell- 

icbaft z868-x894 Ber. 

9. Zeittchrift fiir anorgan* 

itcheChemie •• •• 1892-1894 Zeitt. anorg. 

Chem. 
to. Zeittchrift f^ phytikal- 

itcheChemie •• •• z887*i894 Zeitt. phys. 

Chem. 
iz. Zeittchrift fur Eledro- 
chemie. (Organ der 
deattchen elearocbe- 

mitchen Getelltchaft) 1894 Zeitt. Eledro- 

chem. 
Referencet to papers of importance pnblished in jour- 
nals other than the above are also included. 

Books of Rffifinci, 
z. " Quantitative Analyse durch Eledrolyse." A. Clat- 
ten. 3rd edit., 1892. Publithed by J. Springer, Berlin. 

* Read before the Britieh 4uociation (SeAion B), Iptwich 
Meeting, xSqs. (Second Report of the Committee, coneiitiof of 
Prof. J. fimerton Revnolde, CbeirmaD, Dr. C. A. Kohn» Secretary, 
Prof. P. Frankland. Prof. F. Clowea, Dr. Hugh Marshall, Metin. 
A. B. Fletcher, D. H. Nagel, T, Toriier* and J. B, Coleman). 



Translation, by W. H. Herrick, of and edition, 1887, 
** Quantitative Chemical Analysis by Eledrolysis." Pub- 
lished by 1. Wiley. New York. 

2. •• Elearo-chemical Analysis.*' Edgar P. Smith. 1890. 
Published by P. Biakiston, Philadelphia. 

3. " Jahrbuch der Eledrochemie." W. Nemtt and W. 
Borchert. 1894 (^i^t year of publicatioo). 

Arrangiwunt of Bibliography, 
The bibliography it divided into the foUowing tec- 
tiont:— 
z. General conditiont for eledn^Ttic analytia. 
a. Special apparatus employed. 

3. Quantitative metbodt, for the determination of metab 

by meant of eledrolytit. 

4. QuanUutive methods, for the separation of metals 

by meant of eledrolytis. 

5. Special applications of eledrolysit in quantitative 

analytis. 

6. Applications of eledrolysit to qualitative analytia. 



THE PERIOD • TABLE.* 
By F. RANG. 

The space in the Table between C, Si, and A, j:WJb^ 
it not a real one, but only an unavoidable defoa aimilar to 
that encountered when a globe it mapped on a plane 
surface. 

Every sign in this Table signifies not only its ntnal ele- 
ment, but also every other element in the same aeriet. 
valency, and part of the Table. La and Yb aignifiM! 
therefore. La, Ce, Ny. Py, Sm, Tb, Ho, Er, Tm, Yb, and 
perhapt at many more yet imknown elementa. Their 
atom-volumet and chemical adivity thow that they do 
not make a series. 

Several fads indicate that H it here put in itt right 
place. Now when A is found we no longer have anyrieht 
to be incredible about the existence of the elemenu 
marked (+), and, moreover, we are able in aome 
places of the Table to predid where they are to be found 
€,g,t which elements the explorer could use as ores. We 
are also able in some degree to predid their general pro. 
perties. *^ 

What is now known about A, together with iu periodic 
arrangement, tells ut that it hat the molecule— 
A 
A^l 
^A 
atomic weight 13, and valence IV. A glance at the mofo. 
cular formula of A will explain iU resistance to chemical 
adion ; its molecule is not easily broken, but whap iu 
atoms are once separated, it it likely to get an extended 
chemittry. 



TabU ofHalfforgotUn EUments. 
Atomic weightt. 



Refierence. 



Frohable. Derivation. Chsm. Niws. 
C. •• 



9*44t «.-p. 350° C. .. 64 

Attstriacum, (Ast) .. .. aia 

Neptunium, Np .. .. 236 

Ilmeniuro, II ? 

Polymnestum, Pm.. ., ? 

Erebodium, £b •• .. 94-5 

Gadenium } 

X,X'X' ? 



lix., 295 
XXXV., 197 
XXXV., 197 




♦ See Cbbm. Nbws, vol. Ixvii, p. 178. 



Cbemical Ntwt, I 
Oa.«5,l895. f 



Vapour-pressure of Concentrated Solutions oj Salts. 



201 



VkleiiM. I. 


II. 


III. 


IV. 


V. 


VI. 


VII. 




VIII. 




I. 


II. 


III. 


8criet« 
X. •• 






• • 


• • 


• • 


• • 


• • 


• • 


• • 


• • 


• • 


H 


a. Li 


Be 


B 


c 


• • 


• • 


• • 


,, 


• • 


• • 


• • 


• • 


• • 


3. Na 


Mg 


Al 


Si 


, , 


,, 


• • 


• • 


• . 


• • 


• • 


• • 


• • 


t K 


Ca 


Sc 


Ti 


V 


Cr 


Mn 


Fe 


Ni 


Co 


Ca 


Zq 


Ga 


5. Rb 


Sr 


Y 


Zt 


Nb 


Mo 


Da 


Ra 


Rh 


Pd 


ar 


Cd 


In 


6. Ct 


Ba 


La 


Yb 


Ta 


W 


Url 


08 


Ir 


Pt 


Au 


Hk 


TI 


7. (+) 


Mt 


(+) 


Th 


Np 


U 


(?) 


I?) 


(?) 


(?) 









IV. 


V. 


VI. 


VII. VIII 


He 


• 


(+) 


(+) P) 


A 


N 





P (?l 
CI (?) 


(+) 


P 


S 


Ge 


At 


Se 


Br (?i 


Sn 


bb 


Te 


<i.lD 


Pb 


Bi 


Alt 



4IIIUI • Sc, Pp. 4L6 • Ca, Ng. ellLa and 6lV.a • La, Ce, Ny, Py, Sm, Qd, Tb, Ho, £r, Tm, Dc, Yb. . . . 

^ UnoftinM! element accomptnyioc helinm. 



A most of all known tubttancet violates Dulong and 
Petit's law, and also the general application of Avogadro's 
law ; it has next to H the highest specific heat of all ele- 
ments; its light-refraaion is low in proportion to its 
specific eravity, bat its aiomU volums corresponds ixactly 
to its place in the diagram of the atom-vola me- series. 
(The atomic volumes for C, A, and N are 3*4, 87, and 

X5-5)- 

As some of the elements in my Table have not been 
introduced before in any period-table, and are therefore 
unknown to many, I have, for what good it might be, put 
together the Table in preceding column. 

The sp. gr. of Da and Url give a peculiar and verifying 
■hape to the corresponding parts of the diagram over the 
atom-volume- series. Probably He and its side-elements 
give similar diagram verifications. 

I claim that my period«table is the truest and best 
tabular arrangement of the elsments yet produced ; that 
the table has place for all elements, and fulfils every 
proper requirement of to*day. 



EXPERIMENTS ON THE VAPOUR-PRESSURE 

OF CONCENTRATED SOLUTIONS OF 

SEVERAL SALTS. ESPECIALLY LITHIUM 

AND CALCIUM NITRATES. 

By JOHir WADDBLL, B.SC. (Load.), Pta.D. (Heidelberg), 
Profeetorof Chemistry, Rqyml lliliury College of Canada. 

Thb experiments, of which those described here are a 
few, were undertaiken at *he suggestion of Dr. Goodwin, 
who had himself sent some reports to the British Associ- 
ation, recording the relative amounts of water-vapour 
absorbed by sodium and potassium chlorides, when ex- 
posed to the same atmosphere, They were begun before 
the late development of the theory of solutions and the 
law of vapour-pressure had been enunciated, and a good 
deal of the work done is not now of much value, and I 
therefore do not go into the detail that I should otherwise 
have considered advisable. The majority of experiments 
on vapour-pressore have, however, been made with very 
dilute solutions ; in these which I describe solutions much 
nearer the saturation-point were employed. 

Tbe method adopted was that to which the name 
Invaporation was applied, I believe, by Qraham, and was 
carried out in the following manner : — 

Into a wide-mouthed closely-stoppered bottle, of about 
200 to 300 cc. capacity, three small test*tubes were in- 
troduced, one of which contained water or alcohol, and 
each of the others one of the salts to be experimented 
with. Kiitt some experience had been gained, the liquid 
was frequently added diredly to the salts, and the third 
test*tube dispensed with. 

The salts first chosen for experiment were calcium and 
lithium nitrates; nitrates being seleAed because Dr. 
Goodwin had worked with two chlorides, and these parti* 
cnlar nitrates being chosen because both soluble in alcohol 
as well as water* 

The qoantities of salts taken were molecular, weighed 
in iii.grms. ; but i, 2, or 4 mols. of one salt was taken to 



z mol. of the other, so that in some experiments there 
was a larger amount of calcium nitrate, in others of 
lithium nitrate. So far as the results recorded here are 
concerned there was no necessity for this variation, be* 
caase the numbers retained are all reduced so as to show 
the quantity of liquid invaporated p$r moUcuU of the 
salts. When there was a great excess of one salt, how* 
ever, and a small amount only of the liquid, it sometimes 
happened that the latter was entirely absorbed by the 
salt which was in relatively large quantity ; for example, 
when there were 8 mols. of calcium nitrate to either 2 or 
4 mols. of lithium nitrate, and only about 2 decigrms. of 
water, the latter was all absorbed by the calcium salt, 
and the result was nearly the same when alcohol was the 
liquid. 

Tabu of Quantiiiis of WaUr tak$n ub by 0*164 g^^» ^f 
Calcium Nitratt and 0*069 grm, of LUkium Niirati, 

1 Ca(N05)2 0*189 0*299 0*367 
I LiNGj .. 0'i42 0*232 0*299 
These numbers obtained from experiments in which 

there were 4 mols. of calcium salt to z mol. of 

the lithium. 

z Ca(NOs)a o*z25 0*144 o*i6z o-24Z o*3Z7 
iLi(NOj).. 0*089 o*zo8 o*Z24 o*Z94 0*265 
From experiments in which the ratio of calcium to 
lithium was 2 : z. 

z Ca(NOs)a. o*Z50 o*22z o'2z8 0*295 0*423 
z LiNGj •• o*zo5 0*167 o*Z7Z 0*230 0*339 
From experiments in which the ratio of calcium to 
lithium was z : 4. 

z Ca(NG3)2 o*z37 o*z8o o*2Z7 0*264 0*459 0*521 
z Li(N03) O'zoo 0*135 0*172 0*202 0*327 0*403 
From experiments in which the ratio of calciam to 
lithium was z : 2. 



z CaCNGJa 



, -,- o*z23 o*z29 o'z88 0*246 0*248 
zLiCNGj).. 0*044 0*093 o*Z45 o*Z96 o*Z98 

z Ca(NGa)a 0*365 0*476 0*952 4*228 
z LiNOj •• 0*298 o*4ZO 0*819 3'6Z9 
From experiments in which the ratio of calcium to 
lithium was z : z. 

If a curve is plotted whose ordinates are the quantities 
of water absorbed respeftively by the lithium nitrate and 
the calcium nitrate, it does not differ very much from a 
straight line, though it is slightly concave towards the 
axis of the lithium nitrate. 

The three cases given in which the amount of water 
absorbed by the molecular weight of lithium nitrate waa 
less than o'l grm. represent what was found to be the gene- 
ral phenomenon, namely, that the calcium nitrate absorbed 
between o*z2o grm. and 0*130 grm. of water, and had a 
vapour*pressure equal to that of the saturated solution of 
lithium nitrate. Hence, while the amount of water ab- 
sorbed by the calcium nitrate remained praaically con- 
stant, the quantity absorbed by the lithium nitrate was 
different in the different experiments, there being moie or 
less of the salt undissolved. After this limit had been 
passed, the ratio of the water absorbed by the lithium 
nitrate to that absorbed by the calcium nitrate rangad 
from about four*fi(ths to five-sixths. 



202 



Vapour-pressure of Concentrated Solutions of Salts. {^^'oS!^t^ 



The formula of lithium nitrate being LiNOj, and of 
calcium nitrate Ca(N03)ai if all the molecules of each 
were dissociated into their ions there should be the same 
▼apoor pressure when the amount of water absorbed per 
molecule is in the ratio of 2:3. 

It is therefore plain that the lithium nitrate is dissoci- 
ated to a greater extent than the calcium nitrate. The 
ratio of 5 : 6 would be obtained if two-thirds of the 
lithium nitrate were dissociated and one-half of the 
calcium nitrate. 

In an experiment made with potassium nitrate and 
calcium nitrate, it was found that 1*932 grms. of water 
was absorbed by a molecular weight of the former, and 
2*836 grms. of water by a molecular weight of the latter. 

Suppose half of the calcium nitrate to be dissociated, 
it would follow that one-third of the potassium nitrate is 
dissociated. If it is known to what extent any one of the 
three is dissociated, then it would be known to what 
extent the others are dissociated, but otherwise the ratios 
give rise to indeterminate equations only. 

Experiments were also made with alcohol as the liquid 
invaporated. There was less uniformity than in the case 
when water was employed, partly because the alcohol 
doubtless contained water, as it had not been dried with 
sodium, but was what had either been bought as absolute 
or what had been twice distilled over lime. The result 
may have been partly produced, also, by the fad that it 
was difiScult to make the bottles tight enough to prevent 
the escape of a little alcohol-vapour. Burnt rubber 
digested in alcohol was found to be the most satisfa&ory 
of the different substances tried for the purpose of keeping 
the stopper tight. 

The numbers given were calculated in the same way as 
in the preceding case with water. It will be seen that 
not only does the lithium nitrate absorb more alcohol 
than it should if the calcium nitrate were equally dissoci- 
ated, but molecule for molecule an amount absolutely 
greater. Each molecule of lithium nitrate absorbs ap- 
proximately four-thirds as much alcohol as each molecule 
of calcium nitrate. This condition would be fulfilled 
if all the lithium nitrate were dissociated, and one quarter 
only of the calcium nitrate molecules. 

TabU of Quantities of Alcohol taktn up by 0'x64 grm, of 

Calcium Nitrate and 0*069 grm,of £ithium Nitrat4. 
I Ca(N03) 0*194 0*3x2 0*408 o 6x2 
xLiNOj.. 0*324 0*427 0*575 0*889 
From experiments in which the ratio of calcium to 
lithium was 4 : x. 

I Ca(N03)3 o'X78 0256 0*341 0*474 06x8 0*935 

xLiNOj.. o'220 0*332 0*460 0*696 0*896 1*388 

From experiments in which the rauo of calcium to 
lithium was 2 : i. 

X Ca(N03)t 0*224 o*2^ 0*372 ^'^^ **236 
X LiNOj.. 0280 0*331 0*469 0*845 1*552 
From experiments in which the ratio of calcium to 
lithium was x : a. 

I Ca(N03)a 0*204 0*283 0*360 0*533 
X LiNOj . . 0*244 0368 0*480 0*726 
From experiments in which the ratio of calcium to 
lithium was x : 4. 

X CaCNOsh 0*482 0*7x8 
I LiNOs .• 0*657 0*987 
From experiments in which the ratio of calcium to 
lithium was x : x. 

In order to compare the members of the calcium group 
of metals among themselves and with lithium nitrate, a 
series of experiments was instituted. Barium and stron- 
tium nitrates being less soluble than calcium nitrate, a 
larger quantity of water was needed than for the calcium 
and lithium salts, and within the limits in which I have 
hitherto worked the results are not very concordant ; but 
I give the numbers without delaying the paper for the 
further investigations which I propose making, and which 



will take some time. There seems to be little dooblt 
from what has been done, that the barium nitrmte is the 
most absorbent ; that the calcium salt comes next ; mnd 
that the strontium compound, instead of being inter- 
mediate between the others, is less absorbent than either. 

Tabic of Quantities of Water absorbed by each Moleculmr 

Weight expressed in Milligrammes, 
I LiNOt. . — — 0*460 fx82 — 

X Ca(NOs)a 0*590 x*x66 — — 0-797 

I Sr(N00a 0*504 x*xi5 0*470 1*320 0-685 
X BafNOjlj 



BaCNOjja 

X LiNOt • • 0*327 

I Ca(NOs)a - 

I Sr(NOs)a 0'33X 

I Ba(NOs)a — 



o*76x 
0*830 



— 1-339 
8*205 [* ^1 

— [1495] 
8*994 x-^?" 



The relationship spoken of above will be seen in the last 
column. The unbracketed numbers are the result of 
dired experiment ; of the bracketed numbers that Cor 
calcium nitrate is obtained by calculating the water ab- 
sorbed by that salt as six-fifths the amount absorbed by 
lithium nitrate, and that for strontium nitrate is deduced 
from the figures in the fourth column, where it will be 
seen that strontium nitrate absorbs x*32o grms. of water 
for x*x82 grms. absorbed by lithium nitrate. 

Finally, a series of experiments was made in which tbe 
metal was the same, but the salt radical varied. The 
haloid salts of potassium were chosen for experiment. 
It appears that these salts are very nearly equally disso- 
ciated, even in rather concentrated solutions, but if any- 
thing the bromide is more dissociated than the others. 

Table of Quantities of Water taken up by the Milliptatnmg 
Molecular Weight of Potassium Chloride^ Bromide, 
and Iodide, 
I KCl o*o6o 353 553 126 506 797 
X KBr 0229 377 588 — — — 
X KI 0*229 373 581 229 522 797 
X KCl* 2*070 0088 0*312 747 2*237 
X KBr — 0*229 0*326 784 2*339 
X Kl* x*933 0*229 ©•328 802 2*5x0 

X KCl 0*595 295 248 411 605 1*190 

X KBr o*6o6 3xx 351 — — — 

X KI — — — 428 624 x*ao5 

X KCl 200 407 x*027 266 690 376 

X KBr — — _ 296 — 396 

X KI 226 43 X x*057 — — — 

X KCl 78X 401 78X 769 x88 560 238 
I KBr 827 — — — _ _ 25a 
xKI — 4x5 789 775 233 589 — 

(NoTB.— The numbers marked with the asterisk are 
peculiar, as in no other case does the KCl absorb 
more water than the KI. In this instance aiore 
water had been added originally to the chloride 
than to the iodide, and invaporation does not seem 
to have been complete even after a lapse of two 
years. It turned out that some water- vapour escaped 
from the bottle, for a weighing made since this 
paper was written, and six months after the one 
recorded above, gave KCl 2*033 and KI ''93 1* Thus 
tbe main loss was from the chloride, and I have no 
doubt that now that the stopper has been made 
tight the anomaly will disappear. 

When the quantity of water to be divided among the 
salts was small, a phenomenon, similar to that observed 
with the lithium and calcium nitrate, is again prominent. 
The bromide and iodide absorbed the water, the chloride 
apparently being left dry until the other salts bad ab- 
sorbed a considerable quantity of water. 

In two cases the bromide and iodide have 229 m.grmp. 
of water each, while the amount of water with tbe 
chloride is in one case 60 m.grms. and in another 88 



CHB1IICA& NlWt, I 



Chemical Researches and Spectroscopic Studies. 



203 



m.grm8. In another experiment the same number lag is 
found for the iodide, while the chloride has 126. Still 
another experiment gives 326 with the iodide and 200 
with the chloride. We may therefore conclude that the 
bromide and iodide would probably absorb a constant 
amount of water whenever the quantity is more than 
450 m.grms. and less than a little over 650 m.grms., snd 
that the chloride absorbs what is left over. 

So soon as this limit is passed, the three salts absorb 
nearly the same amounts of water, as shown by the case 
in which the bromide absorbed 257 m.grms. and the 
chloride 348 m.grms. It appears, then, that the bromide 
and iodide of potassium both absorb enough water to 
make a solution, while the chloride is still in the solid 
condition, and when the vaponr-pressure from the bromide 
and iodide comes to be as large as that of the saturated 
solution of the chloride it remains constant until the 
chloride is all dissolved. 

The peculiarity of the lithium nitrate, as compared 
with calcium nitrate, is the most noticeable feature in the 
experiments, and I have therefore begun some experi- 
ments with chlorides and sulphates, which, however, will 
require time for completion. Meantime I made a rough 
set of experiments, on the eledrical resistance of strong 
and dilute solutions of lithium and calcium nitrates. 

6*9 grms, of lithium nitrate were dissolved in 100 grms. 
of water, and to 10*277 grms. of this solution 349 grms. 
of water were added. 

In the same way, a strong and a dilute solution of cal- 
cium nitrate was made. 8*2 grms. of calcium nitrate were 
dissolved in 100 grms. of water, and to 10*377 grm** of 
this solution 352*4 grms. of water were added. 

The resistance of these liquids was determined in the 
following manner i — 

The vessel containing the solution was put in circuit, 
wHh Lord Kelvin's composite balance and his set of anti- 
tndoaive resistance-coils. An alternating current, such 
as used for incandescent lighting purposes, was employed, 
and its eledromotive force was determined by a statical 
voltmeter. The current was read direaiy from the 
balance, the difference of potential was given by the volt- 
meter, and therefore the resistance could be calculated. 
Since the resistance in the box was known, the resistance 
of the solution could be calculated by subtraaing it from 
the total resistance. The vessel in which the liquid was 
contained, whose resistance was measured, was a U-tube 
of about 30 c.c. capacity. The eleArodes were kept at 
the same distance, m the diflerent experiments, by resting 
on the ledges produced by the narrowing of the tube at 
the bend. , , 

The average resistance of the strong solution of cal- 
cinm nitrate was 238 ohms. The average resistance of 
the dilute solution was 3690 ohms. In the case of the 
Uthiom nitrate the resistance of the strong solution was 
167 ohms, and of the dilute solution 4114 ohms. If the 
salts had been equally dissociated in the strong and dilute 
solutions, and if the current is carried only 1^ the disso- 
ciated ions, the resistance of the dilute solutions of the 
calcium nitrate should have been 8100 ohms, and of the 
lithium nitrate 5827 ohms. The resistance of the cal- 
ciam nitrate aaually increases in a much less ratio than 
the dilution, while the lithium nitrate does not show so 
great a divergence. 

The amount of dissociation of the calcium nitrate is 
about 45 per cent as great in the strong solution as in the 
weak, whue the amount of dissociation in the case of the 
lithium salt is about 83 per cent. 

Owing to several sources of error, such as the fludua- 
tion of the elearomotive force of the circuit, and the 
difiSculty of taking accurate readings, when the current 
was small, the results attained do not pretend to close 
exadness; but they show the nature of the change pro- 
duced by dilution, and that in the strong solution calcium 
nitrate is much less dissociated than lithium nitrate. 
Moreover, the result obtained for the latter salt does not 
diff^ very greatly from that given for lithium chloride in 



Ostwald's ** Outlines- of General Chemistry *' (English 
edition, p. 261). 

Nearly all of the experiments in invaporation recorded 
above were with solutions more concentrated than even 
the nearly normal solutions, which were the strongest 
employed for the determination of elearical resistance. 

It was stated that the ratio obtained between the 
quantities of water absorbed by the two salts, when the 
vapour-pressure was the same, would be satisfied if two- 
thirds of the lithium nitrate were dissociated and one-half 
of the calcium nitrate. 

The table given by Ostwald shows that in the normal 
solution of lithium chloride the dissociation is about 61 
per cent, and my experiments on the elearical resistance 
seem to show that lithium nitrate is somewhat similar to 
the chloride. Very probably, then, this calculation is not 
very far astray. 

I should perhaps add that the bottles containing the 
tubes with which the invaporation experiments were 
made were at the temperature of the laboratory, which 
varied between 10* C. and 25^ C. at different times of the 
year. I have weighed the same tube, however, in spring 
and autumn, and the weight was within a m.grm or two 
the same, so that the variations of temperature had no 
appreciable effea. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 
STUDIES OF VARIOUS ELEMENTS. 

By JBAN SBRVAIS 8TA8. 
(Oootisned from p. 190). 

So long as a speAroscopic examination enables one to 
detea the presence of sodium in a flame burning in air, 
either ai rat or in motion, this air imparts to platinum, in 
whatever state it may be, the property of colouring the 
flame yellow. Spon^ platinum possesses this property 
in a marked degree. 

The time necessary for the deposit of sodium on plati- 
num is very variable; with the ordinary air of the 
laboratory from ten to fifteen minutes are sufficient, 
whilst several days* exposure are necessary for producing 
the yellow colour in the flame when the air only shows 
slight traces of sodium. 

Even spongy platinum, when kept lying in a glased 
cupboard m dry air, in which spearum analysis is unable 
to detea the presence of sodium, only acquires the pro- 
perty of turning a flame yellow after several days' 
exposure ; but a speArum analysis of the flame be/on it 
has changed colour shows a faint image of the sodium 
D line. 

It follows from these experiments that it is always the 
air which deposits sodium on platinum. 

Silver behaves like platinum. When properly refined, 
as I have described, it shows no trace of the sodium 
spearum. After having been left in air in which spearum 
analysis shows a bright yellow sodium line, it impacts a 
distinaiy yellow tint to a Bunsen burner flame, and 
shows a strong sodium line. This colour quickly disap- 
pears ; but if the metal be covered with atmospheric dust 
It colours the flame vellow, and this property remains 
until it has been melted and properly refined in a lime 
crucible. 

The tubes and silver fittings, when kept in air, should 
be carefully washed with water mixed first with hydro- 
fiuoric acid, then with hydrochloric acid, and afterwards 
with pure water. 

Bone-black when refined behaves exaaiy like platinum 
and silver. It attraas the deposit of sodium. It should 
be kept in air-tight fars^ and should never be used until 
after having been raised to white heat. 

Platinum, silver, and carbon, when kept protected from 
atmospheric dust in cupboards, well-closed glass cases, 
under bell-jars, &c., acquire a deposit of sodium on their 



204 



Chemical Researches and Spectroscopic Studies. 



IGBBIIICALllBWt. 
1 Oa. J5. 1^95* 



sarfjtces. The sodium is evidently contained in the out- 
side air which continuously mixes by diffusion with the 
air inside the cupboards, cases, and jars. The rapid 
deliquescence of highly soluble compounds, when left in 
these confined spaces, is evidence of the rapid rate of 
diffusion. This fad, moreover, is known to everybody 
who puts drying agents into cases, however air-tight they 
may be, to preserve instruments or chemical compounds 
from the adion of water vapour in air. 

Bxperience has taught me that one must moisten the 
inner surface of the tubes and metal or rubber fittings 
used to bring the gas from the reservoir to the apparatus^ 
and never to use rubber tubes desulphuretted by placing 
them in a boiling solution of dilute hydro-oxide of sodium. 
When undertaking this desulphuretting one day I lost 
time in looking for the reason of the presence of a great 
deal of sodium. The soda penetrates into the rubber; 
the illuminating gas, by attacking it, charges itself with 
sodium when passing through a rubber tube desulphur- 
etted with hydrate of sodium, even although the tube has 
been washed with water containing a little acid and then 
dried. 

It was by pondering over the above fads and conclu- 
sions that I sought to solve the problem of ascertaining 
if it be possible to obtain metals and metallic compounds, 
which, at the highest temperature attainable, should not 
show the charaderistic spedrum of sodium on spedro- 
scopic examination, and whether one could thus change 
the spedrum of metals the one to another, or at least 
produce the charaderistic rays of the spedram of one 
metal by using a compound of another metal. 

Having described my researches on the spedra of the 
metals on which the experiments were conduded, I must 
describe the method used to vapourise them and the in- 
strnments I used. 

On the Methods of Volatilising Metals and their 
Compounds, 
I have used, one after the other, all known methods for 
attaining this end: they consist of the introdndion o 
the bodies into — f 

I. The outer envelope of the Bunsen burner flame. 
a. The outer envelope of a pure hydrogen flame issuing 
from a platinum blowpipe. 

3. A blowpipe jet of pure hydrogen and pore air. 

4. A jet of pure hydrogen raised to incandescence by 

the admixture of oxygen. 

5. A jet of coal-gas rendered colourless by the ad- 

mixture of oxygen. 

6. The internal cone of an oxyhydrogen blowpipe. 

7. The internal cone of an oxy-coal-gas blowpipe. 

8. An indudion-spark from 2 to 5 m.m. between the 

points, with or without condensers capable of giving 
respedively sparks of 5, 15, and 45 cm. length, 
the substance being either solid, or melted, or in 
solution in pure or acidulated water, and either in 
air or hydrogen. 

9. A discharge from 5 to zo m.m. between the 

points, capable of giving sparks from 15 to 45 cm. 
long, having from one to five very large Leyden 
jars intercalated, the substance being either solid or 
dissolved in acidulated water, and either in air or 
hydrogen, 
zo. An eledric arc formed successively between pure 
carbon eledrodes : zst, by 30, 50, 100, or 200, of 
the very largest Bunsen cells ; 2nd, by a battery of 
33 Julien accumulators, giving at the terminals of 
the lamp zo amperes and 30 volts, and forming an 
arc 9 m.m. long by about 8 m.m. diameter ; 3rd, by 
a Gramme and Siemens dynamo coupled, giving at 
the terminals of the lamp from 28 to 30 amp%res 
and from 60 to 80 volts, and forming an arc 2\ cm. 
long by about 8 m.m. diameter; 4th, by a zo,ooo 
candle power dynamo.* 

* io the deacriptlont of the lumiooas spedtra of sodium, Ittbinm, 
caicium, Btrontinm, barium, and thallium, 1 give details of the use 
made of the arcs from different batteries anddynamos 



These methods having been previously used, and their 
applications being known, I can limit my description to 
pointing out some fads that long pradice has taught me. 

Oo the Position to be given to Flames when Examining 
their Spectra, 

Messrs. Bunsen and Kirchhoff recommend placing the 
dark part of an ordinary gas flame or a hydrogen flame 
in front of the slit in the collimator, and putting the 
platinum wire loop, or coil, with the compound to be 
vapourited, in the middle of the outer envelope of the 
flames on the side opposite the slit. 

It is a well-known fad that, with a minute quantity of 
incandescent vapour, we can produce spedra which leave 
nothing to be desired on the score of distindness, when 
the light thus obtained is sufficiently intense ; but this 
condition can only be realised when working with very 
volatile bodies. It is not the same with less volatile 
compounds. In this case it seems better to set the jets 
beside the collimator so that the right or left edge of the 
flames is exadly opposite the slit with the centre of the 
edge in the axis of the collimator. By arranging it thus, 
one gets all the rays proceeding from a compound 
vapourised in the middle of the outer envelope of the 
flames. To satisfy oneself that this arrangement intensi- 
fies the light, it is sufficient to compare the spedrum of 
chloride of barium in both positions in the same flame, 
whether Bunsen burner or hydrogen. I am aware that 
under these conditions the rays have not all the same 
focus ; but the same inconvenience is found in the usual 
method, because, when introducing the subsunce to be 
volatilised, one almost always pierces through the dark 
envelope and penetrates too far into the flame. I am wil- 
ling to admit that the method I have adopted is less con- 
venient than the one generally used, and that it requires 
pradice to do it quickly. The difficulty of doing it is a 
good guarantee for the accuracy of the result. It is, in 
fad, necessary to place the flame so that the centre of iu 
dark envelope is exadly on the axis of the collimator ; 
this necessitates the absolute immobility of the flame — 
an immobility hard to obtain in a room where the air is 
more or less in motion, but still it may be obtained by 
using screens to shield the flame from air-currents, or, 
better still, by maintaining a constant pressure of from 
2 to 4 cm. of water by means of a hvdrogen and air or 
coal-gas and air blowpipe, with a Durner ending in a 
platinum noxzle with a hole from | to z m.m. in diameter. 
With the flame in this position, using a sufficiently nar- 
row slit, one avoids, as far as possible, oblique rays, 
and the background of the spedrum is always dark, 
whether there be lines or no. By the usual method a 
continuous spedrum appears so often 'that all spedro- 
scopists imagine potassium and sodium to have a con- 
tinuous spedrum, although I have proved that the parts 
in the neighbourhood of the sodium D line or potassium 
lines are completely free from luminosity, even although 
the potassium and sodium compounds be put into almost 
incandescent hydrogen, such as an oxyhydrogen blowpipe 
fed with a proper quantity of oxygen. The easiest 
method of adjusting the flames is as follows :— On one 
side I arrange on a board, on the table of a strong 
camera-stand used to carry the spedroscope, the Bunsen 
burner, and the hvdrogen, hydrogen and air, oxyhydrogen, 
or oxy-coal-gas blowpipe, surrounded by screens to pro* 
ted them against lateral air-currents. This board, the 
length of which is nearly half the width of the table, moves 
by means of an endless screw at right angles to the axis 
of the collimator of the spedroscope. To efled this the 
worm works in an easily turned screw, which is fixed by 
its collar in a bearing on the left side of the table. 

On the other side, on a second board, which occupies 
the right half of the table, I arrange the holder used in 
putting the compounds into the outer envelope of the 
flames. The second board also moves at right angles to 
the axis of the collimator, by means of an endless screw 
attachment on the right side of the table. 



CBBMICAL NlWl, \ 

oa. as. 1895. f 



London Water Supply. 



205 



By this metna the endless screw attached to the board 
on the itft causes the burner or blowpipe on it to advance 
or recede from Uft to right, whilst that on the right causes 
the holder on the other board to move forward or back from 
right to U/t. 

As the pitch of the screw is very fine, a millimetn at 
ths outsidt, one can bring the rays from the incandeseent 
vapour under spedroscopic examination into the axis of 
the collimator of the spedroscope with great accuracy. 

This arrangement enables the observer to move either 
the flame or the holder without removing his eye from the 
eyepiece of the speAroscope ; this is necessary when he 
only has small quantities of matter to deal with, because 
be can work alone without injuring the relative purity of 
the air, and at the same time avoid any error following 
the appearance of a line caused by disturbing the flame. 

Experience has taught me that in order to completely 
avoid a continuous spedrum, one must eliminate rays 
from the incandescent holder. These rays extend farther 
than is generally thought. In many cases they extend more 
than a cm. along the holder. One effeas this by putting 
the compound into the flame at least two aniimttres from 
the edge of the slit through which the rays pass, and by 
arranging in front of the slit in the collimator movable 
platinum diaphragms which can be opened or closed at 
will, according to the height of the luminous beam re- 
quired to pass the slit. Many spedroscopes a^ually have 
an attachment for this purpose, especially the large in- 
stroments made by M. Hilger. 

I have already described the Bunsen burner as much 
as is necetsaty, so I need say nothing further about it. 

On thi Bl<mpipt,^K% for the apparatus used for pro- 
ducing the hydrogen jet, or the hydrogen and air, oxy- 
hydrogen, coal-gas and air, or oxy-coal-gas blowpipe, it 
consists of a tube of platinum, silver, or copper, accord- 
ing to circumstances, bent near its free end to a right 
angle, ending in a nozsle of platinum, silver, or pure 
gold. The bore of the nozzle is from I to z m.m. dia- 
meter, according to the length of flame I want to 
obtain with a constant pressure of 2 or 4 cm. of water, 
measured by a manometer inserted between the blowpipe 
and the gasometers. I use a platinum nozzle, with an 
opening ^^ m.m. wide and x cm. long, when I want a 
simple sheet of burning hydrogen. Before being adjusted 
to the bent tube, the nozzles are always washed with 
dilute hydrofluoric and hydrochloric acids, then with pure 
water, and finally heated to redness. 

To guard against explosions, I use as a blowpipe ther 
well-known apparatus employed by Mr. O. Matthey fo 
fusing platinum. The mixture of gases used in it may 
be varied at will, by the taps fitted to it. 

I think I ought to mention that it is necessary to wash 
and keep moistened with pure water the inside of the 
blowpipe, so as to prevent the presence of, and conse- 
quently avoid detaching, adherent sodium dust. The 
terminal tube of the blowpipe is held in a vice working 
on a rack on a vertical stand. The arrangements are 
such that I can have at will, at a pre-arranged height, a 
vertical, horizontal, or sloping jet, according to the con* 
ditions I have to satisfy. 

In the note on the thallium line in the flame and elearic 
spearum, I fully explain the use of the hydrogen and air 
and coal- gas and air blowpipe flame. 

(To be coDtioQed). 



A New Black Ink.^Mr. Q. Vickers, of Angel Court, 
Strand, is introducing a new blue-black non-corrosive ink 
having properties that should recommend it to the writing 
public. It is very fluid and dries a fine black, works well 
with ordinary steel pens, and does not go s icky ; it will 
therefore be useful for stylographic pens, ftc Acids 
appear to have less effed upon it than upon many of the 
aniline inks now on the market. 



LONDON WATER SUPPLY. 

RSPORT ON THB COMPOSITION AND QUALITY OP DAILY 

Sauplbs op THB Watbr Supplibd to London 
POR THB Month Ending Sbptbubbr 30TH, zSgs* 

By WILLIAM CR00KB8, F.R.S.. 

and 

PROFESSOR DBWAR, F.R.S. 

To Major-Qbnbral A. Db Courcy Scott, R.E., 
Wattr Bxamifiir, Mitropolis Wat$r Act, 1871. 

London, Oaober lotb, iSgs. 
Sir, — We submit herewith, at the request of the 
DireAors, the results of our analyses of the 175 samples 
of water colleaed by us during the past month, at the 
several places and on the several days indicated, from the 
mains of the London Water Companies taking their 
supply from the Thames and Lea. 

In Table I. we have recorded the analyses in detail 
of samples, one taken daily, from Sept. ist to Sept. 30th 
inclusive. The purity of the water, in reaped to organic 
matter, has been determined by the Oxygen and Com- 
bustion processes; and the results of our analyses by 
these methods are stated in Columns XIV. to XVIII. 

We have recorded in Table II. the tint of the several 
samples of water, as determined by the colour-meter 
described in a previous report. 

In Table III. we have recorded the oxygen required to 
oxidise the organic matter in all the samples submitted 
to analysis. 

Of the 175 samples examined all were found to be 
clear, bright, and well filtered. 

The weather during September has been in every reaped 
remarkable, the rainfall in the Thames valley having 
dropped from 3*66 inches (the average of 25 years), to 
0*57 inch, leaving a deficiency of 2*09 inches. Rain fell 
on six days only, the bulk of it, 0*39 inch, on Sept. 6th. 

This, together with the excess of sunlight, has had a 
marked efled on the quality of the water, as can be seen 
by the following table : — 

Comparison of ih$ Av$rag4S of th$ Fivt Tha$n$s*difiv$d 
Supplitsfor thi Months of August and Stptsmbn, 1895. 

Common Nitric Ozygea. Organic Orfsnie 

Salt. Add. HardncM. reqd. Carbon. Carbon. Cokmr. 
Per Per Per Per Per, 

gall. gaU. Degrees. g«ll. gall. gall. Br'n:Blne 
Means. Meana. Meana. Ileane. Meant. Max. Means. 
Aug. 1*994 0*740 13*09 0*039 0093 o'zoS zi7:20 
Sep. 1*980 0*685 13*97 0*032 0*081 0*098 10*4:20 
Baderiological examinations of the filtered and uo* 
filtered samples have been carried 00 uoremittedly 
throughout the month, and we find that the average of raw 
unfiltered Thames water contained 2432 microbes per 
cubic centimetre, and river Lea water 17 10 microbes per 
cubic centimetre ; whereas the filtered samples from the 
five Thames Companies contained only 62 microbes per 
cubic centimetre, and the filtered Lea water 73 microbes 
per cubic centimetre. 

We are. Sir, 

Your obedient Servants, 

William Crookxs. 
Jambs Dbwar. 



Researches on the Essence of Bergamot and on 
its Sophistications. — Dr. Ignaaio Campolo. — This 
essence is an oily mobile liquid of a dark yellow colour, 
an acrid and pungent taste, and a pecuhar, delightful, 
and penetrating odour. It has a slightly acid readion, 
and a specific gravity at 15° of 0887. Like the other 
essences of the Aurantiacess it is optically aAive, de- 
flediog the plane of polarised light to the right. The 
principal sophisticants to which essence of bergamot is 
liable are fatty oils and resin. The weight of residue 
left by the genuine essence on evaporation does not ex- 
weed 6 per cent. The increase of the weight in sophisti- 
cated samples is equal to the quantity of olive oil added. 



2o6 



Determination of Uranium. 



i Cbbmicai. Nbw«« 
1 Oa. as* i89S- 



DETERMINATION OF URANIUM 

IN ORES CONTAINING PHOSPHORIC AND 

ARSENIC ACIDS. 

By R. PRS8ENIUS aod B. HINTZ. 

iN^the determinttion of uranium in ores containing phos- 
phoric and arsenic acids, copper, and iron, by means of 
ordinary methods various difficulties were encountered. 
In the first place, the precipitate consisted chiefly of 
arsenic and copper sulphides, and sulphur could only be 
obtained free from uranium after repeated precipitations 
by hydrogen sulphide in an acid solution. Secondly, the 
presence of phosphoric acid greatly increases the difficulty 
of separating iron from uranium. 

A method was therefore sought for of precipitating 
uranium from an acid solution, in order thus to effeA the 
separation of phosphoric and arsenic acid. For this pur- 
pose precipitation with potassium ferrocyanide seemed a 
suitable means. But if the precipitation of the uranium 
is efieaed in the ordinary manner, the result is that the 
precipitate of uranium ferrocyanide scarcely subsides and 
cannot be filtered oiT. But if, after the addition of the 
potassium ferrocyanide, the liquid is saturated with 
sodium chtoride, the precipitate quickly subsides, and can 
be easily filtered and washed with water containing sodium 
chloride. 

On the basis of these fads, the determination of 
uranium in ores containing the above-mentioned in- 
gredients can be executed as follows without difficulty :— 

We first separate as usual the silica from the solution 
in nitric or hydrochloric acid or aqua regia, add an excess 
of potassium ferrocyanide to the slightly hydrochloric 
solution, and saturate the liquid with sodium chloride. 
The precipitate, which subsides quickly, and contains 
uranium-, copper-, and iron-ferrocyanides, is first washed 
by decantation, and afterwards on the filter completely 
with water containing sodium chloride, and is then 
treated in the cold with dilute potassa-lye. After the 
transformation of the ferrocyanides is completed and the 
hydroxides have deposited, the liquid is poured off through 
a filter, washed once more by decantation with water, 
rinsed on to a filter With a little water containing ammo- 
nium chloride and ammonia, and washed with the same 
liquid without interruption until potassium ferrocyanide 
can no longer be recognised in the filtrate after acidula- 
tion. 

The hydroxides are then treated with hydrochloric acid, 
in which they dissolve completely if the above-mentioned 
operations have been correAly carried out. If there re- 
mains an insoluble residue of ferrocyanide it must be 
washed and again treated with potassa-lye, as above 
direaed. 

The solution of the metallic chloridos which no longer 
contain phosphoric or arsenic acid, if the precipitated 
ferrocyanides have been well washed, is concentrated if 
necessary, the greater part of the free acid is neutralised 
with ammonia; the Hquid (still clear) is mixed with am- 
monium^carbonate in moderate excess, allowed to stand 
for some time ; the ferric hydroxide which remains undis- 
solved is filtered off, washed with water containing a little 
of the filtrate with the addition of the washings, heated 
in order to expel the chief part of the ammonium car- 
bonate, acidified with hydrochloric acid — whereby the 
yellowish flocculent precipitate formed on boiling, and 
containing a part of the uranium, is re-dissolved — and the 
copper remaining in the solution is precipitated with sul- 
phuretted hydrogen with the application of heat. The 
copper sulphide was always obtained free from uranium. 
The liquid filtered from the former is concentrated, the 
uranium precipitated with ammonia, and the precipitate 
of uranium hydroxide is converted into uranicuranous 
oxide by ignition in an uncovered crucible, and weighed 
as such. As a check-experiment, it is then converted 
into utanous oxide by ignition in a current of hvdrogen, 
and the weight is again determined.— Z#i^«An/( fur 
AnafyUschi Chemist xxxiv., p. 4370 



NOTICES OF BOOKS. 



KufMes Handbuch der KohUnhydraU, (II. Band). By 
B. ToLLBNS. Breslau : E. Trewendt. 1895. 

Modern chemistry is like modem music in acknowledging 
more and more the sway of the UU-motif, Reading the 
history of the science backwards, it is always easy to 
give a '* too, too solid form " to that which is only a ghostly 
presence ; in other words, to discover the dominant theory 
of a period long before it existed. But in dealing with 
tht forward movement of our own present time, the 
ordering and systematising of the group of carbohydrates, 
there is no doubt that the results in this case are begotten 
of the theory. Nor could there be any better exemplifi- 
cation of the charaAer of the movement than a careful 
comparison of the volume before us with its predecessor 
(I. Band, 1888), of which it is a substantial amplifica- 
tion, and in some reipefts a revision. The Uit-mot^, it 
is hardly necessary to premise, is the theory of the asym- 
metrical satisfadion of the four combining positions of 
the C-atom ; this, as the basis of the ** new isomerism,^ 
which specially charaderises the carbohydrates. 

Nor is it necessary to make more than a passing allu- 
sion to the ** Seer " of the movement. Emil Fischer's 
position in relation to the subjed-matter of the book is 
duly recognised in the author's preface. His work as a 
pioneer investigator has about it, we may remark, much 
that is unique. For while it has undoubtedly carried with 
it a number of discoveries of compounds and metbodtt 
with perhaps the attendant stimulus of novelty, its main 
purpose was the laborious verification of a striAly matbe* 
matical or geometrical forecast. Such **high academical *' 
work is rare in our science, and it has a moral aspeft 
which ought to give pause to those who talk lightly of 
** finde siicU evolution.'* 

We may contrast the "sugar movement" with the 
great development which preceded it — the chemistry of 
the aromatic series. This involved the elaboration of an 
equally striking chapter in isomerism, but the principles 
were in this case evolved aposUriori, The ** inwardness *' 
of this movement, ^moreover, centred in large measure 
round the peculiar, but extrinsic, attraAiveness of the 
particular compounds which were brought to light with a 
prolific fertility. No one so far as suggested any striking 
development of art or industry as likely to follow from the 
discovery of the thirteenth hexanpentolal. Still, the 
melancholy conclusion that *' there may be no money in it 
after all ** — a finally destrudive argument in many spheres 
of adivity — would have had no more deterrent effect upon 
the pursuit of this particular No. 13 than it has had in 
damping the ardour of North Pole enthusiasts. 

But, to the book. The author needs no introduaion to 
English chemists. His researches in special chapters of 
the now great volume of carbohydrate chemistry are well 
known ; and his contribution of experimental methods 
has been especially valuable. No one will question his 
qualifications for the task of chronicler of the movement 
in which he has taken so adive a part, and, with the two 
monographs which he has produced before us, we are 
justified in saying the work could not have been in better 
hands. A preliminary idea of the scope and magnitude 
of the present volume (Part II.) will be gathered from the 
fad that there are over laoo references to original 
papers. The systematic arrangement of the subjed- 
matter is necessarily based upon the classic work of 
Fischer, of which the Maestro himself has given a com- 
prehensive digest in his papers entitled " Synthesen in der 
Zuckergruppe " {Bert, Bir., 1890, p. 2114; 1894, p. 3189), 
The general relationships of the group, as disclosed by 
systematic synthesis and dissedion (Abbau), the broader 
questions of constitution, and the more refined conclu- 
sions as to configuration, are dealt with in a preliminary 
sedion, which also includes a general account of the 
more special charaderistics of the group, e.g,^ optical 



Oa. aSf 1895. * 



Justus von Liebig. 



207 



Eroperties, thermal constants, fermentation, and other 
ydrolyses. This sedion is admirably condensed into 55 
pages of the text. Candidates for competitive examina- 
tions will rejoice in the prosper hereby afforded of 
*' getting up '* this great subje^ in the compass of, say, 
one evening I 

The table of genealogical descent of the typical hexoses, 
^•glucose and d-fruAott, from formaldehyd, acrolein 
bromide, and glycerin, will appeal with force to the 
** cram *' school of students. In the more serious view, 
it affords an excellent perspedive of a whole campaign 
of methodical struggle. We will not, however, discuss 
the author's preamble according to its ** location,*' but, to 
follow an excellent precedent, after the encyclopaedic por. 
tions of the work have been noticed. In dealioe with 
this, the experimental subjed-matter, the author follows 
the received order : — (a) The carbohydrates proper 
(aldoses and ketoses) are dealt with as mono-, di-, and 
tri-saccharides, i,e., generally the crystal Usable sugars, in 
order of molecular weight, and lastly, the poly-saccharides ; 
(6) the mannites or mannitols, or corresponding alcohols; 
U) derivatives of the cyclic hexamethylene (inosite, 
quercite, ftc.) ; and lastly, {d) the diversified group of 
saturated poly-hydroxy-acids derived from, or constitu- 
tionally related to, the carbohydrates. 

There is little to be said in criticism of these sedions. 
It is difficult to see how the work could have been more 
carefully done. To have seleded the subjed-matter from 
over 1200 original papers, and reproduced their essential 
features in 300 pages of text, is an invaluable effort of 
digestion and concentration. Specialists will possess 
themselves of the book at once, as a matter of course, 
and their judgment of its value will not be influenced by 
** these presents " ; nor would its value as a work of refer- 
ence be materially lessened by any objeAions on points 
of detail. Those who are not specialists can afford to 
believe in a ftw substances of doubtful identity, and ac- 
cept some conclusions which they may have to unlearn, 
without prejudice to the advantage of taking a categorical 
survey of a careful census of this well-marked province of 
chemical individuals. 

Thus, on the doubtful side. Some of the conclusions 
as to the identity of isomaltose will, in view of Brown 
and Morris's recent work, require revision. The author's 
view of the molecular strudure of cellulose may be 
summed up as that of an *' acetal " union of unit Ce- 
groups, against which there appears to be a good deal of 
experimental evidence. This particular sedion, which 
includes the ligno-celluloses, has an amorphous charader. 
But so have the compounds themselves, and hence the 
** Cinderella " position they continue to enjoy. II we 
wished to be oracular, we should prophesy concerning 
Ibis sroup of OQt*casts and the Twentieth Century* 

It IS evident that no useful purpose would be served by 
an examination in detail of the encyclopssdic matter of 
the text. It is of necessity a compilation : no pains have 
been spared in the coUedion and ordering of the experi- 
mental material, and considering the difficulty of photo- 
graphing an expanding group — if we may be allowed the 
simile — the author is very much to be congratulated on 
the result. 

What is perhaps of greater moment is the general plan 
of the work as sketched in the preamble, which is, or 
aims to be, coextensive with the present development of 
the subjed. This we think is somewhat too narrow; 
possibly the author has circumscribed it with intention. 
Those who follow the literature of the subjed are aware 
that it is overflowing in every diredion into the province 
of the physiologist. In fad, the sugar chemist is tx officio 
a physiologist. Fischer himself having laid his strudural 
foundations on the most purely academic lines, now finds 
nnexpeded relationships of configuration to both the 
construdive processes of assimilation and the destrodive 
processes of hydrolysis and ferment re-solutions. Brown 
and Morris, in this conniry, have contributed a memoir of 
fundamental import upon the root problems of assimila- 



tion. ToUens, also, and his students past and present, 
are doing valuable work in physiological problems. 

Of course the inevitable consequence of exbaustiva 
investigation of the carbohydrates is to open out the 
whole province of plant chemistry. But there are farther 
consequences in view. The whole science of carbon 
chemistry is becoming involved. We have had a 
century of "pure chemistry." We have learned to 
treat matter as matter, wtth a resped which our 
mediseval ancestors failed even to anticipate. At this 
date we take Matter very much for granted (writing 
it with a capital M), and find our fascinations in 
problems of form. So far as these are purely geometrical 
they tend to finalities. Of course we could go on multi- 
plying analogues to the end of time. But there enters 
the question of brain or mind exhaustion, and the anti- 
dote of new objedives. The new objedive of organic - 
chemistry is the chemistry of living organisms. We see 
its operation in all hands ; there is no need to enforce the 
conclusion by demonstration. At the same time we do 
not feel ** superfluous " in calling attention tb this general 
convergence or divergence of research in connedion 
with the subjed of the book before us. As we have in- 
dicated, the author is sparing in his treatment of the 
physiological relationships of the subjed-matter. The 
suggestive conclusions of Fischer, as to the relationships 
of assimilation and ferment resolutions to the configura- 
tion of the assimilating substance or ferment, are very 
sparingly noticed. There is no mention of the observa- 
tions of A. J. Brown on the cellulose- forming properties 
of Bacttrium xyUnum, There are no special references 
to that most interesting problem presented by the natural 
history of the carbohydrates, vis., the passage from satu- 
rated to unsaturated compounds. On the other hand, a 
glance at the Index will show that particular references 
to plant produds are extremely numerous, and, as a know- 
ledge of the author's researches, leaves us in no doubt as to 
his being a great student and patient investigator of the 
chemical problems of plant-physiology, we must conclude 
either that the plan of the work is not to admit of the 
discussion of physiological problems which is perhaps 
conveyed by the title, or that the task of dealing with 
these is deferred to a third volume. 

If, therefore, the work in its present state of develop- 
ment leaves us with this one impression of shortcoming, 
it may be the result of a little trop d$ mU$ on our part. 
Still we can all of us afford to be a little over-xealous 
when not engaged in putting ourselves **on record "; and 
it will be well if our teachers will put all their spare en- 
thusiasm into a definite shaping of the careers of pro- 
mising students towards the new fields of investigations 
now opening np. 

Prof. ToUens's work is perhaps too stridly academical 
to be diredly suggestive of fruitful subjeds of research. 
But with the interpretations and forecast of the teacher it 
cannot fail to exert a most valuable influence in furthering 
the progress of the newest " New Chemistry," which is 
the chemistry of the plant cell. 



yustus von Liihig : His Lift and Work (1803 to 1873). 
By W. A. SUENSTONB, F.I.C., Ledurer on Chemistry 
in Clifton College. Small 8vo., pp. 220. London, 
Paris, and Melbourne : Csssell and Co., Limited. 1895. 
Mr. Shbnstonb is right. Though not a quarter of a 
century has elapsed since Justus von Liebig joined the 
majority, and great as had been his services to Science 
and to the roost useful of all the Arts, he is, save in 
scientific and technical circles, nearly forgotten. Our 
author mentions two instances showing how little he is 
known even among the ** educated and respedable" 
classes. One current notion is, that Liebig was a man 
who gained a large fortune by maldng ** extrad of meat." 
Others think they have heard his name mentioned in con- 
nedion with agriculture. A very common mistake is the 
notion that Liebig's father was a pharmacist, and that 



208 



Chemical Notices from Foreign Sources. 



I Crihical NBWt» 

1 oa. 23. 1895. 



the great luminary of Giessen and Munich himself was 
brought up to the same career. He had certainly been 
placed for a short time with an *' apothecary,** or, as he 
would be termed in England, a ** chemist and druggist ;** 
but after ten months bis non-pharmaceutical experi- 
ments proved so alarming that his master was glad to get 
rid of him. 
The work before us deals not so much with Liebig*s 

Srivate life as with his career and his influence upon 
rermany and upon the world. But there is one point to 
which attention cannot be too forcibly and too frequently 
drawn. In the earlier part of the century in Germany — 
as it is still to a deplorable extent in Britain— the mental 
calibre of a youth was judged solely by his power of 
assimilating the ''classics," of remembering long strings 
of rules and exceptions, and of playing with ** longs and 
shorts.** Liebig had little verbal memory, and no taste 
for word-mongering. Hence he was denounced as a 
dunce, likely to be a disgrace to his teachers and his 
parents. What an instrudkive mistake ! The classical 
scholars who were considered so greatly his superiors 
have passed, leaving the world no wiser than they found 
it, whilst Liebig has bequeathed to future generations a 
solid inheritance of research which is still continuing to 
grow and to bear fruit. 

After an Introdudion, and an account of his friendship 
for Woebler and of their joint researches, the author goes 
on to describe Liebig's discoveries in pure chemistry, his 
relations with Dumsis, — which were not uniformly har- 
monious,~his acceptance of the fruitful dodrine of sub- 
stitution, his researches on fermentation — involving a 
dispute with Pasteur, of which Mr. Shenstone speaks 
perhaps too favourably. We have then his epoch-making 
contrioutions to the chemistry of agriculture and to phy- 
tiological chemistry. 

A special chapter is worthily devoted to his educational 
work. To him, more perhaps than to any other man, is 
due the splendid upburst of intelledual life which has 
made the German universities foci of discovery, and has 
even contributed powerfully to the development of 
German manufaAuring industry. It has been said that 
the first Napoleon was able to *' spit ** generals. In like 
manner it may be said that Liebig could ** spit '* disco- 
verers, inventors, professors, full of originality and 
carrying on the work of their great master. 

Liebig*s " Familiar Letters on Chemistry ** are not 
overlooked. It is very truly said that these letters " had 
much to do with the present intelligent attitude of the 
German * practical man * towards Science, which has 
contrasted so strangely with that of his average English 
brother for many years past, much, it is to be feared, to 
the material disadvantage of the latter.** The German 
has learnt that, to ensure manufaAuring superiority, 
abundant capital, business tad, and energy are not suffi- 
cient without a knowledge of the scientific principles on 
which the various industrial arts are based. 

Mr. Sbenstooe deserves hearty thanks for the produAion 
of a work so opportune and so useful. 



A Short Manual of Analytical Chemistry ^ Qualitative and 
Quantitative, Inorganic and Organic : following the 
Course of Instrudion eiven in the South London School 
of Pharmacy. By John Muter, Ph.D., F.R.S.E., 
F.I.C., &c. ; Analyst to the Metropolitan Asylum 
Board; Public Analyst for Lambeth, Wandsworth, 
Southwark, Newington, Rotherhithe, and the Lindsey 
Division of Lincolnshire ; Past President of the Society 
of Public Analysts ; late Editor of the Analyst, Sixth 
Edition, Illustrated. London : Simpkin, Marshall, 
Hamilton, Kent, and Co. (Limited) ; and Baillidre, 
Tindall, and Cox. 1895. 

The work before us, though primarily intended for the 
guidance of pharmaceutical students, will be found widely 
useful. Setting out with a view of the processes em- 
ployed by praoical chemists, the author proceeds to the 



deteaion of the metals in which cerium is included, 
though indium, rhodium, thallium, and uranium are 
omitted, doubtless as not being used in medicine. 

Next follow methods for the deteaion and separation of 
the acid radicles, the qualitative analysis of mixtures of 
unknown salts, the qualitative dete^ion of alkaloids of 
some other organic substances used in medicine, and a 
general sketch of procedure in toxicology. 

Successive chapters treat of weighing, measuring, and 
specific gravity, no notice being taken of the very uselesa 
hydrometer of Beaum^ Next follow instruaions for 
volumetry and the use of the nitrometer, the gravimetric 
determination of metals and acids, for the determination 
of phosphates in soils and manures, and for the full 
analysis of the organic matters in potable waters. In- 
strudions are given in ultimate organic analysis, the 
nitrogen being determined according to the processes of 
Dumas, of Varrentrapp, and of Kjeldahl. 

In Chapter X. there are given special processes for 
the sanitary examination of waters, of air, and of the 
more usual articles of food. Referring to Pepper, we 
cannot help asking why the importation of '* poivrette *' 
is still permitted ? Special processes are laid down for 
the analysis of the more important drugs, of urine, and 
urinary calculi. 

In the concludiue chapter there are instrudions, neces- 
sarily rather brief, for gas analysis— now of rapidly 
increasing importance— and of polariscopic and spedro- 
scopic analysis. The sedion on the analysis of urine U 
enriched with illustrations, showing the microscopic 
aspedts of pus, micrococci, uric acid, cystin, blood discs, 
triple phosphates, &c. 

Dr. Muter*s work is, in short, a useful work of reference. 



CHEMICAL 



NOTICES FROM 
SOURCES. 



FOREIGN 



NoTB.— All degrees of temperature are Centigrade uoleu otherwiae 
expreMed. 

Compiei Rendus Hebdomadaires des Siances, d€ V Academic 
des Sciences, Vol. cxxi.. No. 15, Oaober 7, 1895. 

An Ascent to the Summit of Mont Blanc, and on 
the Researches Executed during the Summer of 
Z895. — ^J. Janssen.— The author has studied the presence 
of watery vapour in the atmospheres of the sun. The 
spedrum was entirely deprived of its rays of an aqueous 
origin ; all the group near D was absent, as well as that of 
C ; a was so pale that it was difficult to decide if it was 
in its place. It was evident that on another step every 
aqueous manifestation would have disappeared. 

Study of certain Meteorites.— Henri Moissan. — The 
author has resumed the study of certain meullic or holo-> 
sideric meteorites in consequence of the discovery of a 
transparent diamond in the meteorite of Cafion Diablo. 
He arrives at the following conclusions :~In some holo* 
sideric meteorites there is no carbon ; in others we find 
either amorphous carbon, or a mixture of this variety and 
of graphite. In a single meteorite, that of the Cafion 
Diablo, the author has found together the three varieties 
of carbon— diamond (black and transparent), graphite, 
and amorphous carbon. 

Inflammability of '* Fire-damp." — R. L. Devaux 
proposes to annul the in6ammability of '* fire-damp '* by 
an admixture of carbon dioxide. 

Mechanical Properties of the Alloys of Copper and 
Zinc— Georges Charpy.— This paper can scarcely be re- 
garded as a chemical communication. The most advan* 
tageous alloys are those containing from 30 to 43 percent 
of zinc, and their value then diminishes rapidly. The 
elongation before rupture also increases with the pro- 
portion of sine, and then decreases rapidly. 



Cbxmical Niwt, I 
oa. 15, 1895, f 



Chemtcal Notices from Foreign Sources. 



209 



Qlociottm Carbide.— P. Lebeau.— On heating in the 
ale^ic furnace a mixture of glucinom oxide and of coke 
we have obtained, not the metal, but a definite carbide. 
Pore glucina wa« intimately mixed with half its weight of 
ssgmr charcoal. The mixture was agglommerated with 
m little oil and compressed into the form of small cylinders, 
which were then heated to incipient redness. The 
cylinders were then introduced into a tube of coke, closed 
at one end, and arranged in such a manner that the mix- 
two was in the hottest part of the furnace. The current 
employed was of 950 amperes and 40 volts. The experi- 
aarat required from eight to ten minutes. In a series of 
cxperimenu with a current of 350 ampdres and 50 to 60 
▼Mts, there was only obtained a nitride, or produds con- 
Cmining nitrogen and carbon. Pure glucinum carbide ap- 
pears in the form of yellowish brown microscopic crystals 
presenting hexagonal facets. It easily scratches quarts, 
and its specific gravity at 15° is x '9. Chlorine attacks it 
readily at a doll red heat, forming a volatile chloride and 
m black residue of amorphous carbon and graphite. Bro- 
mine reads at a rather higher temperature, and iodine 
has no aAion at 8oo^ Pure oxygen at dull redness pro- 
duces a superficial oxidation. Vapour of sulphur reads 
below 1000°, forming a sulphide. Phosphorus and carbon 
bave no apparent adion at dull redness. The composi- 
tion of the carbide appears to be C3Be4. The atomic 
weight of glucinom should be close upon 14, and glucina 
should be a sesquioxide, BejOs. 

Reaearcbet on the Combinations of Mercury 
Cyanide with the Iodides. — Raoul Varet. — A thermo- 
chetuical paper not of sufficient importance to warrant its 
insertion m full. 

Double Decompositions ensuing between Mercury 
Cjanide and tbe Alkaline and Alkaline-eartby Metals. 
— >Raool Varet.^The fluorides, chlorides, sulphates, 
nitrates, carbonates, acetates, and picrates of these metals 
do not oodergo double decomposition with mercury 
cyanide. With the bromides there is a slisht double de- 
composition. With the iodides there is double decom- 
position, regulated by the produdton of the triple salu 
HgCya, MCya, Hgla. With the sulphides there is com- 
plete double decomposition. 



Bml'€tin dt la SocUU Ckimiquc de Paris. 
Series 3, Vols, xiii.-xiv.. No. xa, 1895. 

Certain Derivatives of the Bromides in Cj.— R. 
Lespieau.— An account of x . a . 3-tribromopropane ; of 
1 . 3-dibromopropane ; of 1*3. 3*tribromopropaoe oxy- 
methane ; i . a-dibromopropene oxymeihane ; and i- 
bromopropine oxymethaoe. 

Bensinesulpboortbotoluidine and some of its 
Denvative8.---Ch. Rabout.—We see the great resistance 
of this sulphamide to oxidation, and its great stability in 
heat to the presence of dilute acids, notwithstanding its 
amidic charader. 

Determination of Organic Nitrogen by tbe Kjeldabl 
Process, m tbe absence of Nitrates.— H. Causse. 

Volatile Acidity of Wines.— H. Jay.— The propor* 
taona of volatile acids found in French and Spanish wines 
of reliable origin oscillates between 0*38 and 080 grm. 
per litre, calculated as monohydrated sulphuric acid. On 
(Oe contrary, all the Algerian wines which have been sub- 
mitted to me contain per litre at least x-30 grms., and in 
a majority of cases exceeding x*6o grms. 

Determination of VolatUe Acids in Wines.- £. 
Barcker. 

No. X3. 

Mew Tube for FraAiooated Distillations Modified 
bj M. LcbeL— G. Berleroent.— This apparatus cannot 
be described intelligibly without the accompanying figure. 



New Researches on tbe Combination-beats of 
Mercury with other Elements.— Raoul Varet. — The 
heat disengaged in the combination of mercury with 
gaseous chlorine is -1-53*3 cal. ; with liquid brominei 
+40*6; with iodine, solid, +25*2 cal (for the red com- 
pound) and 22*2 cal. (for the yellow compound); with 
oxygen, gaseous, -hsx'S cal. 

Isomeric Transformations of tbe Mercury Salts.— 
Raoul Varet.— A list of the heats developed by the mer* 
corial compounds in their respedive transformations. 

Separation of Lime from Strontia and Baryta.— J« 
Dupasquier. 

AAion of Halogens on Methylic Alcohol.— A. 
Brochet. — This paper is not adapted for useful abstrac* 
tion, and cannot claim insertion fit gxtgnso. 

Preparation of tbe Amines of tbe Patty Series.— 
A. TriUat.— Tne author gives an account of the prepare? 
tion of monomethylamine, of the adion of ammoniacal 
salts upon formaldehyd, the influence of redudioo 00 the 
preparation of ethylamine. 

Recognition of Alum in Wines.— M. Georges. — 
The author proposes the two following solutions :^x« 
Solution of pure tannin— Pure, 3*40 grms.; distilled 
water to make up xoo c.c. Bach cc. of this solution 
precipitates 0*005 grm. alumina, i,#., the quantity con* 
tained in 00463 grm. of alum. 2. Solution of sodium 
acetate— (C4HsNa04.3HaOa) or (CsH3Na02,tHaO) ; 
neutral sodium acetate, crystalline, 24 grms. ; distilled 
water to make up xoo cc. Bach c.c. of this solution 
contains a weight of combined acetic acid corresponding 
to o*to grm. monohydrated sulphuric acid. The author 
measures 20 cc. of wine into a wide test-tube, and adds 
a c.c. of the solution of tannin. After agitation, he pours 
into the mixture 3 c.c. of the solution of sodium acetate, 
stirs again, and then leaves the mixture to settle, observ- 
ing the phenomena produced. If, after five minutes, 
there appears a clotty precipitate we may assert the pre- 
sence of alum. If the wine remains clear, or is at most 
slightly cloudy, the wine is genuine, or contains less than 
X decigrm. of alum per litre. 

Existence of a Sulphuretted Substance in CottOD 
Oil. — J. Dupont. — American food-fats containing 
cotton oil have often become rancid, and in that state 
have a deceptive adion with the silver nitrate. The 
author distils cotton-oil in a strong current of steam. The 
water coUeded has a disagreeable smell of a sulphuretted 
produd. On successive treatments with ether there is 
obtained a small quantity of an oily matter which is 
attacked in the water-bath with nitric acid and potassium 
chlorate. If the excess of acid is driven ofi* and the residue 
taken up in water the addition of barium chloride deter- 
mines a strong precipitate of barium sulphate 

Use of Superphosphates. — Jules Joffre. — The 
author's experiments warrant the conclusion that the 
preferable aidion of superphosphate is not merely due to 
a more thorough dissemination in the soil, but to absorp- 
tion of a part of the phosphoric acid in the state of com- 
pounds soluble in water. There is no proof that reverted 
phosphoric acid exists in the soil in the state of tricalcic 
phosphate. 

Exposition of some Points concerning the Ana- 
lysis of Patty Substances. — O. Halphen. — The author 
gives, firstly, an examination ol the physical charader- 
istics, specific gravity, viscosity, spedroscopic behaviour, 
polarisation, solubility, congelation, expansion, and 
elastic condudivity. The physical methods just enume- 
rated are not of themselves sufficient. Among the che- 
mical methods, it is pointed out that Faur6*s test, the ac- 
tion of chlorine gas, is not decisive ; some vegetable oils 
are not bleached by this reagent, but turn brown ; whilst 
some animal oils, especially that of the feet of Dorses, are 
blackened. The Welman*s test and the phosphoric acid 
method are not trustworthy. 



2IO 



Hygienic Decision on Potable and Household Waters. 



MISCELLANEOUS. 

Hygienic Decitloo on Potable and Household 
Weters.~Prof. FlQgge.— At the General Meeting of the 
German Attodation for the Care of Public Health, Prof. 
Fli&gge put forward the following propositions :— z. The 
ctistomary hygienic decision on waters simply on the basis 
of a chemical, baderiological, and microscopic examina- 
tion of samples sent, is in almost every case to be 
lefeded. a. A sinsle examination of water as to its ad- 
missibility for drinxing or domestic consamption must, 
above all things, be followed by a visit of inspedion to 
the place where the sample was taken. In many cases 
this examination alone leads to a conclusion that it may be 
supplemented by macroscopic inspeAion, and a deter- 
mination of the hardness and the iron. In new installa- 
tions the freedom of the water from micro>organisms 
shoold be ascertained. 3. The hygienic significance of 
remarkable analytical results can be generally ascertained 
only by repeated inspedion and examination. — Zsit, /*. 
Angiwandti Chsmis. 

ACSXONS— Answering all requirements. 

ArOXJ^ .A-OIB3TIO— Pu>*st and sweet. 

— BOI^-A.OIO— Cryst. and powder. 

— OITI&IO— Cryst. made In earthenware. 
— • Gh.A-XjXjIO— Prom bett Cbtoeie c*ll>» part, 

S.A.XjIO'X'XjIO— By Kolbe's process. 

— T^innO— Pe*" Pharmacy sod the Arts. 

LIQUID CHLORINE 

(Compressed in steel cylioders). 

FORMALIN (40J& CHaO)~Antiseptic and Preservative. 

POTASS. PBRMANOANATB-^Cryst., large and small. 

8ULPH0CYANIDE OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THE ARTS 




Wholesale Agents— 

A. & M. ZIMMERMANN, 

6 A 7, GROSS LANE LONDON, E.G. 

OLD PLATINUM 

M ik^ In any form PuacHAssD for Cash. 

Hif best prices allowed by 
ROBERT PRINGLB ft CO., Gold and Silver 
/ISl^^ Refiners, ftc., 40 and 42, Clerktowell Rd., B.C. 

^O ©^^ Send for Price List. 

Photographic Residues reduced and porchased. 

THE CHEMICAL NEWS 

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DeUrmination of Argcn. 



an 



THE CHEMICAL NEWS. 



Vol. LXXII., No. 1875. 



NOTE ON THE REDUCTION 

OP THE OXIDES OF IRON BY MEANS OF 

CARBON MONOXIDE. 

By ISAAC BRAITHWAITB. 

Fbkkic oxide, formed by igniting the precipitated hjrdrate, 
in grannlar powder which woald ptBt through a sieve of 
x8 nieahei to the inch, but not through one 28 to the inch, 
was heated in a porcelain tube to a Tow red heat. Suc- 
cessive small portions of CO were passed over it, each 
portion being passed back and forward repeatedly (from 
ten to twenty times) during a period of about five minutes 
(in some cases much longer). The proportion of COa in 
each portion was determined by absorption in notash 
and weighing. This was repeated until the oxide was 
completely reduced to metallic iron. The results were 
DOt sufficiently accordant to warrant the giving of exaa 
figures. Probably this may have arisen from several 
causes. The temperature may not have been sufficiently 
miform, although one or two direA experiments showed 
BO marked change in the results when the temperature 
was raised considerably above that usually adopted. The 
CO employed was not quite pore, and probably varied a 
little. The time durins which each portion was allowed 
to aft certainly affeded the results ; the most accordant 
ones being obtained when the aftion was prolonged many 
boors ; but as some hundreds of successive portions were 
used, it was impraaicable to allow so much time for 
Mch. 

The fads ascertained may be stated generally thus :— 
At a low red heat, in presence of excess of Fea03, CO is 
completely (or almost completely) oxidised to COa. With 
excess of Fej04, rather more than two-thirds is oxidised 
to COai the resulting mixture of gases being nearly 
CO+aCOa. With excess of FeO, about one-third is 
oxidised, leaving the mixture nearly aCO+COa. When 
the iron is completely reduced, if the temperature falls 
below a dull red heat, there is considerable formation of 
COa and deposit of carbon, probably from the formation 
and decomposition of iron carbonyl. The experiments 
were reversed by passing COa over iron, and the adion 
was proved to be reversible ; that is, COa passed over red- 
hot iron became two-thirds reduced ; over FeO, one-third 
reduced ; over Fe304, not reduced at all. 

I am indebted to Mr. 8. R. Rowling for the carrying 
oot of these experiments. 



A NEW FORM OF ACCUMULATOR. 
By H. N. WARREN, Research Analyet. 

Tbk invention relates to accumulators of a special type, 
whereby an extraordinary large surface of material is ex- 
posed. The negative element, consisting of a plate of 
pure porous lead, is manufadured for the purpose by partial 
compression in suitable moulds of spongy lead obtained 
by the slow precipitation of lead from a solution of the 
acetate by means of xinc; around this is compressed, 
again, an intimate mixture of metallic lead and litharge, 
made by melting lead in a deep clay crucible, and intro- 
ducing into the same about 40 per cent of litharge, the 
whole being well stirred until cold. By this means a 
thorough incorporation of the litharge is obtained, the 
metallic appearance of the lead present being entirely 
masked* The metallic lead as produced in the first in* 



stance, together with the litherode lining, is tightly com- 
pressed into thin flat porous pots, each plate thus 
forming one negative element. For the constmdion of 
the positive plates is prepared an intimate mixture of lead 
peroxide, by first incorporating with the lead, as in the 
former instance, instead of litharge* barium carbonate ; 
the resulting granular powder thus obtained being after- 
wards freed from the barium carbonate by digesting the 
same in hot hydrochloric acid, thus leaving the lead in a 
state of purity, which is afterwards mixed with a suffi- 
ciency of the plumbic peroxide and used as a charge for 
the positive cell, or to constitute, in other words, the 
positive plate. The resistance in such accumulators is 
very small, whereas at the same time they compare mote 
favourably with others as regards their amperage. Plates 
of this description are now to be obtained at most of 
the leading eiedricians, and will be found highly bene- 
ficial to those requiring to demonstrate the pradical con* 
strudion, and at the same time the charging, of accumu* 
lators to classes or others ; being rapidly charged by 
small batteries, and retaining the current admirably. 

Liverpool Research LaboratofF. 
18, Albion Street, Bverton, Liverpool. 



ON THE DETERMINATION OF ARGON. 
By Tb. SCHLCESING. Jun. 

SiNCB argon has been discovered the question has been 
raiaed whether, like the other elements of the atmosphere, 
it interferes in the phenomena of life. 

The experiments hitherto made on this point have given 
negative results. Q. McDonald and A. M. Kellar have 
sought for argon in the composition of certain animals 
and certain seeds, but they have not met with it in an 
appreciable quantity. Nevertheless the subjed is not 
exhausted, and it will doubtless be further examined, es- 
pecially if argon plays a part in vegeuble synthesis. 
For such a study it may be useful to determine with pre- 
cision the argon contained in a given atmosphere. I have 
attempted this determination, to which I have been the 
more attraded because, independently of any physiolo- 
gical research, the determination of argon applied to 
normal air is doubtless of interest. 

In consequence of its rarity we are naturally led to de- 
termine argon in very large volumes of air. But the mea- 
surement in the manifeststion of large volumes of gases 
generally involves bringing them in contad with water, 
whence there result nearly siways sensible errors. It is pos- 
sible to obtain good results by operating only on volumes 
of air corresponding to 1*5 litres of nitrogen, and efieding 
all the measurements over mercury. We then employ 
for the separation of argon and nitrogen a system of ap- 
paratus 01 limited capacitv, when it becomes easy to 
produce a vacuum, as well before the introdudion of the 
gas to be measured as after its extradion, which consti- 
tutes a most precious resource. 

After the example of Lord Rayleigh and Prof. Ramsav, 
to isolate the argon contained, #.^., in normal air, I ab- 
sorb the nitrogen of the air by means of magnesium after 
having eliminated the oxygen and the carbonic acid. 

The arrangement for this purpose cannot be described 
intelligibly without the accompanying figure. The 
author's procedure has been carefully verified. 

It has been enquired if argon treated in this manner is 
sufficiently purified. To ascertain this point I have taken 
specimens of the gas obtained in the determinations. 
Oxygen hss been added, and the mixture has been sub« 
mitted to the adion of the spark in presence of potassa 
for eight hours. The oxygen has then been eliminated by 
means of pyrogallol and the gaseous residue measured 
anew. I have, i»g,, found : — Initial volume, 15*796 c.c. ; 
final volume, 15*802 c.c. The difference is very smallt 
and is of the degree of the errors of measurement 



213 



Vapour-Unsians of Mixtures of Volaiile Liquids. 



f CBBMIC4L MlWa, 

1 Nov. I, iflgs. 



I have made a global verification (so to apeak) of the 
procedure. I prepared chemical nitrogen by pasting over 
copper and copper oxide, at a red-heat, nitrous oxide ob- 
tained bf the decomposition of ammonium nitrate. I 
measured this nitrogen after having added an accurately 
estimated volume of argon obtained from a determination 
condoded on my method. The proportions of the two 
gases was of the same degree as in the atmosphere. The 
mixtore hat undergone afi the operations and manipula- 
tions indicated. I compared the volume of argon intro- 
doced to that of the argon recovered. Three experiments 
of this kind gave :» 



Oueoas mixtore introduced. 



Percentage 
of the 
▲fgOQ Loee. Arcoo 

recof w ed. Total, iatrodoced. 



Cheadou 
Afgoo. Nitfogea. 

!• 18*138 cc 1395*6 cc 18*008 ex. 0*130 0*72 cc. 
a. 18*155 M MOQ'a ,1 18*083 •• 0*072 0-40 „ 
3.' 16-930 „ xa88*x „ 16*809 „ 0*127 Q75 „ 

These figures give an idea of approximation obtained. 
I shall retom to the cause of the small loss observed, and 
give an account of the determinations efieded both of 
normsl air and of other gaseous mixtures, such as those 
extradced from the soil. At present I will merely sa^ that 
normal air yielded as a mean (number obtained without 
corredion) X'x83 vol. of argon to xoo vols, of atmospheric 
nitrogen (nitrogen and argon), or 0-935 vol. to xoo vols, 
air, figures which approximate in deficiency to less than 
xoo 01 their value.^Cam>f#s Rindus^ cxxi., p. 525. 



DETERMINATION OF HEAVY METALS BY 

TITRATION WITH SODIUM SULPHIDE. 

By O. NEUMANN. 

It Is known that most alkaline metals are precinitated 
quantitatively from their solutions by an alkaline sulphide. 
This reaAion is utilised by mixing the metallic solution 
In question with a known excess of the precipitant, and 
titrating back the excess of sulphide. As the alkaline 
sulphides have an alkaline reaaion, we might expeA that 
the ofajea might be attained without using an excess of 
alkaline sulphide by taking litmus or phenolphthalein as 
an indicator as in the titration of acids. Experiments in 
this direaion, however, proved useless, since alkaline 
sulphides, like hydrogen sulphide, destroy the colour of 
the indicator. 

On this account the neutral metallic salt to be analysed 
was placed in a measuring flask along with a considerable 
excess of a dilute standardised solution of an alkaline 
sulphide, and the flask was filled up to the mark with 
water. As the precipitates formed are sometimes not 
very dense and do not readily subside, there was added 
in molt cases a 20 per cent solution of sodium chloride 
hi/oTi filling up to the mark, and the liquid well ahaken 
and thus qutcldy clarified. An aliquot part of the clear 
liquid was boiled with a measured excess of decinormal 
sulphuric acid until the vapour on being tested with moist 
lead paper was found free firom hydrogen sulphide, and 
was then titrated back with decinormal potassa, using 
phenolphthalein as an indicator. The quantity of metal 
originally present may then be calculated. An example 
may explun these general indications. For standard- 
ising the sodium sulphide there were taken decinormal 
potassa, (?) decinormal sulphuric acid. i7*x cc of the 
solution of sodium sulphide was boiled with 30 cc. 
sulphuric acid until all sulphuretted hydrogen was 
expelled, and used with phenolphthalein as indicator, 
XX -Sec potassa for neutralisation, whence the sodium 
sulphide was calculated as x-os/xo normal. 

With this solution we titrated, i,g,, 1/5 normal solution 
of potassium chrome alum. 25 cc. of this liquid were 
mixed in a 200 cc. flask with 20 cc. of a 20 per cent 



solution of sodium chloride and 50 cc of the aboTO 
solution of sodium sulphide, and filled up to the mark. 
After shaking up the contents of the flask, green chromioa 
hydroxide quickly subsided. 50 cc of the liquid were 
poured through a folded filter and boiled with 5 cc of 
sulphuric acid until the complete exptilaion of the sulphur- 
etted hydrogen, and titrated back with 4*8 cc potassa. 

From these data there was calculated a proportion of 
0*526 per cent CraOj as against 0*5 x per cent theoreti- 
cally. 

The author has shown that the method ta widely 
applicable, as he has made experiments with ordinary 
alum, potassium-chrome alum, ferro-ammonium sulphate, 
ferric chloride, manganese- ammonium sulphate, nickel 
ammonium sulphate, cobalt, sine, and copper sulphates, 
lead and silver nitrates, and cadmium sulphate 

With metals, the sulphides of which are readily sepa- 
rated in a granulated state, the addition of eodiom 
chloride was sometimes omitted. In some metals, the 
salts of which are precipitable by sulphuretted hydro- 
gen in an acid solution, and those, such, t^., 
as copper, form colloidal sulphides on the addition 
of sodium sulphide, the separation of the sulphide 
was efie^ed by the addition of an acid. The 
analysis was then effeded by heating the mixture of 
metallic salt and sodium sulphide in a measuring flaak 
with a measured excess of sulphuric add until the 
readion of sulphuretted hydrogen no longer appeared, 
filling up to the mark when cold and titrating a filtered 
aliquot part with potassa. The author has applied this 
method in determinations of lead as well as of copper. 

The method is of course only applicable if the 
salts under examination are neutral. If acid the free 
aciditv must be expelled prior to titration. Most chlorides 
lose their excessive hydrochloric add if thev are dried op 
on the water-bath, taken up in alcohol and again dried. 
Such experiments were effeded with an acid solution of 
sine and copper. Here a three- fold evaporation with 
alcohol at 97 per cent was the most favourable. After a 
fourth evaporation from alcohol, the residue did not yield 
a clear solution. The evaporation is efleded very rapidly 
if air is blown upon the surface of the liquid. Sulphates 
are previously converted into acid chlorides by treatment 
with barium chloride and hydrochloric add. This is 
best efieded in a measuring flask, and an aliquot part ta 
then drawn off with a pipette as above described. 

Nitrates must be twice evaporated down with con- 
centrated hydrochloric acid, and then made neutral aa 
already described. » ZHtschri/t fur AnalyU CfumU^ 
xxxiv., p. 454. 



ON THE VAPOUR-TENSIONS OP MIXTURES 
OF VOLATILE LIQUIDS.' 

By C. E. LINBBARGBR. 
(Gootioaed from p. 196). 

Bxpifiminial RaulU with Mixtmns qf Normal Liquids. 

In the ioUowing Tables (II. to IX.) are given those data 
of the experiments necessary for the calculation of the 
vapour-tensions. The superscriptions over each column 
of data render any preliminary mention here tmneceasary. 

Rtlatitnu bstwuu thi Va^r4iHsionSt Partial and Totals 
and thi Concentration of th$ Liquid Phaus. 

We remark first, that the tension of the mixed vaponr 
emitted by any of the mixtures of volatile liquida 
examined is always greater than the tension of the leas 
volatile liquid and always less than that of the more 
volatile liquid ; also, that the partial tension or pressore 

• Abrideed from the JoumuU of th$ Amtricon Chemital Soctc^, 
vol. xvti., MO. 8, Aogtut, iSgs* 



Chimical Niwt, I 
Nov. 1, 1895. I 



Vapour 'tensions of Mixtures of Volatile Liquids. 



213 



Tablb Ih—Vapouf'Tifisions of Mixtuns of Benzent and Monochlorhenzine at 34*8'. 



Vapour-tension of Benzene at 34*8^ is 145*4 n>*»^* of Mercery. 
Vapour-tension of Chlorbeocene at 34-8 is 20*3 m.m. of Mercury. 



lfola.G,H«Olin 

too mols. of 
liquid miitnrt. 


Molt. C«H«01 in 

100 molt, of 
gaseoui mixture. 


29*08 
65*06 
79*21 


6*11 
19*37 
35-15 



Grmt. 

C«H«C1 in 

vapour. 


Qrmt. 

C.H.in 

vapour. 


Tension of 
C.H.Cl 
in m.m. 


Tention of 
C.H, 
in num. 


Volnme of 

air 

in m.m. 


0*0454 
0-0857 
0*1800 
0-3572 


23075 
0*9143 
0*5202 

0*4750 


12*3 

19*1 


124*6 

101*3 

5»'3 

27*9 


3782 
X900 
2032 
3787 



Barometer 

in 

m.m. 

763 

757 
758 

756 



Internal 
pretture 
in m.m. 

II 

17 
18 
12 



Tablb III. — Vapouf'Tinsions of Mixtuns of Toluim and Monochlorbenxtm at 34*8^. 

Vapour-tension of Toluene at 34-8^ is 46 8 m.m. of Mercury. 

Vapour-tension of Chlorbeoxene at 34*8° is 20*3 m.m. of Mercury. 

Mols. C«H«C1 in If ols. C,H«C1 in 

too mole, of too molt, of 

liquid mixture. gaaeoui mixture. 

18*96 9*84 

41*82 22*66 

76*71 67*79 



Grmt. 

C«H«C1 in 

vapour. 


Grma. 

CH.iu 

vapour. 


Tention of 
C.H.CI 
in man. 


Tension of 
m m.m. 


Volume of 
air 
in CO. 


Barometer 
in 
m.m. 


Internal 
pressure 
in m.m. 


0*0510 
00985 
0-2089 


0*3821 
02754 
0*0821 


«7'5 


38*2 


1963 


757 


17 
21 
18 



lfols.C«H«Brin 

too mole, of 
liquid mixture. 

3033 



Tablb IV, ^Vaponr-Tinsions of Mixtuns ofBenxim and MonobrombtuMim at 34-8*. 

Vapour- tension of Benzene at 34*8** is 145*4 ni.m. of Mercury. 

Vapour-tension of Brombenzene at 34*8° is 8*0 m.m. of Mercury. 

Mole. C«H«Br in Grma. Grmt. Tention of Tention of Volume of Barometer Internal 

100 molt, of 0«H«Brin C«H« in C«H«Br C«H« air in pressure 

gateottt mixture. vapour. vapour. in m.m. in m.m. in ex. m.m. In m.m. 

24*30 00395 0-4975 2*6 103*1 1018 757 13 



Tablb V.—Vapour-Tinsions of Mixtuns of Btnxtni and Chloroform at 34*8^. 

Vapour-tension of Benzene at 34*8° is 145*4 m.m. of Mercury. 

Vapotir-tension of Chloroform at 34-8° is 289*2 m.m. of Mercury. 

Molt. CHCI, in Molt. CHCl. in 

100 molt, of 100 molt, of 

liquid mixture. gateout mixture. 

l6*97 24*30 

50*53 63-74 

59*47 n'2S 



Qrmt. 
CHCl. in 
vapour. 


Grmt. 
C,H« in 
vapour. 


Tention of 
CHCl. 
in m.m. 


Tentioaof 
C.H. 
in m.m. 


Volume of 
air 
in C.C. 


Barometer 
in 
m.m. 


Internal 
pretture 
in m.m. 


0*3243 
II513 
1*4770 


0*6607 
0*4187 
0*3531 


39*6 
1307 
1622 


123*5 
74*3 
59*a 


1032 
1030 
1030 


?S8 

749 


25 
^5 
85 



Tablb Vh^Vapour-Tinsions of Mixtuns of Tolmne and Chloroform at 34*8^. 

Vapour-tension of Toluene at 34*8'' is 46*8 m.m. of Mercury. 

Vapour- tension of Chloroform at 34-8° is 289*2 m.m. of Mercury. 

IColt. CHCl. in Molt. OHCl/in Grmt. Grmt. Tention of Tention of Volume of Barometer 

iooaBolt.of xoomolt.of CHCl. in 0,H«in CriOl. CfH. air in 

liquid mixture. gateout mixture. vapour. vapour. in m.m. in m.m. in c.c mjn. 

28*74 <55*29 0*4856 0*1994 64*7 34*4 1040 747 
60*43 89*20 1*3578 0-1270 i6o'9 19*5 1031 754 



Internal 
pretture 
in m.m. 

24 
23 



Tablb \ll. —Vapour-TinsioHs of Mixtuns of BiUMsm and Carbon Titrachloridi at 34*8**. 

Vapour'tension of Benzene at 34*8^ is 14^^*4 mm. of Mercury. 

Vapour* tens ton of Carbon Tetrachloride at 34*8^ is 169*4 m.m. of Mercury. 



Molt.CCl«in 


Molt.CCl«in 


Grmt. 


Grmt. 


Tention of 


Tention of 


Volume of 


Barometer Internal 


too molt, of 


too molt, of 


CCl«in 


C.H.in 


COI. 


O^H. 


air 


in pretture 


liquid mixture. 




vapour. 


vapour. 


in m.m. 


in m.m. 


incc. 


m.m. in m.nu 


iS-68 


9-66 


0*1741 


0*8260 


»4*5 


X35-4 


1205 


762 18 


20-54 


6*3931 


0*7561 


32-5 


125*5 


1205 


758 20 


2800 


35'7« 


0-6267 


0-5730 


60-0 


i05'o 


1016 


756 12 


5019 


5503 


1*1231 


0*4666 


91-3 


75-6 


. 1201 


762 19 


63-88 


5527 


1-2699 


0-3431 


103*1 


54'5 


1219 


760 27 

754 26 


7789 


83-01 


1*5321 


0*1669 


117*6 


31*8 


1034 



Tablb VllL^Vapour-ttusions of Mixtures of Toluent and Carbon Tstrachloridi at 34*8°. 

Vapour-tension of Toluene at 34*8^ is 46*8 m.m. of Mercury. 

Vapour-tension of Carbon Tetrachloride at 34*8^ is 169*4 in*in- of Mercury. 



Mo*sCCI«in 
too molt, of 
liquid mixture. 


Molt.CCl«in 

100 molt, of 

gateout mixture. 


3069 

5385 
60-00 
91-87 


58-19 
67*86 
8367 

9r22 



Grma. 
CCl«in 
vapour. 


Grmt. 

C,H.in 

vapour. 


Tention of 

ecu 

in m.m. 


Tention of 

C,H. 

in m.m. 


Volume of 
air 
in C.C. 


Barometer 

in 

m.m. 


Internal 
pretture 
in m.m. 


0-4754 
09305 
09624 


1*2046 
0*1260 
0*1126 
0*0281 


78-3 
99*1 

155I 


37-0 

22*3 

19-4 

45 


1016 
1022 
1020 
IOI7 


756 
758 
759 
756 


12 
«7 
X4 
13 



214 



Vapour-tensions of Mixtures of Volatile Liquids. 



f CBBMIC4L NsWtt 
\ . KoT. 1, 1895. 



Mola. Oa« in 

xoo moll, of 

liquid mixture. 

5*37 
5073 
73*54 
95-21 



Tablb lX,'-'Vapour-Tinsions of Mixtuns of NifrobiHMim and Carbon TitraekUmdi at 34-8^ 

Vapour-tension of Nitrobenzene at 34-8° is z*z6 in.in. of Mercniy. 

Vaponr-tension of Carbon Tetrachloride at 34-8^ is 169-4 <n.m. of Mercury. 

Mols. CCl«in Grmt. Grmt. Tension of Tension of Volameof 

loomols. of CCl«in CiH^NOain CC1« C«H«NOa eir 

gaseons mixtnie. vaponr. Tsponr. in m.m. in m.m. in cc. 



93*5X 
94*47 
96-09 
98*61 



Grms. 
CC1« in 
vaponr. 


Grms. 

C«H«NO,in 

▼aponr. 


0-3095 
z-iizz 


0*0175 
00489 


1*4420 
2*7798 


0-0471 
0*0190 



z8*9 
"3*9 
141-5 
167-6 



1*3 
6*2 

5-6 
2-3 



1973 
1020 

7022 
1022 



Barometer 
in 
mjn. 

760 
756 
753 
753 



Internal 



in ni.fli« 
20 
12 

x8 

18 



of either component, of any mixture, is always less than 
the vapour* tension of the component in a state of purity ;* 
these |wo properties belong to all the mixtures investi- 
ffated. In the discussion of the other properties, we shall 
nnd it convenient to divide the mixtures into classes. In 
the first class we put the mixtures of benzene and toluene 
with monochlor- and monobrombenzene ; in the second, 
the mixtures of chloroform with benzene, and with 
toluene; in the third, the mixtures of carbon tetrachloride 
with toluene, and with benzene ; and in the fourth and 
last, the mixture of nitrobenzene and carbon tetrachloride. 

Now the mixtures of the first class are made up of 
liquids which are very simular in their chemical con- 
stitution, and it is natural to exped that they will exhibit 
the very simplest phenomena when mixed with one 
another. And, indeed, this expeftation is realised, for 
the vapour-tensions of their mixtures are seen to be linear 
funaions of the concentration: in the graphic repre- 
sentations (abscissae B molecular percentages; ordinates 
* vapour-tensions) of the determinations, these fall upon 
or very close to the straight lines conneding the points 
on the axes of ordinates corresponding to the vapour- 
tensions of each of the pure liquids. In order to find the 
vapour-tension of any mixture of these liquids, all that is 
necessary to do is to conned on the axis of ordinates, the 
points representing the vapour-tensions of the two liquids 
m a state of purity, by a straight line, and where the 
perpendicular to the axis of abscissae cuts this line, the 
value of the ordinate corresponding to the point of inter- 
sedion gives the vapour-tension of the chosen concentra- 
tion ; of course, partial tensions can be found in a similar 
way. Also, by the application of the *' rule of mixtures," 
it IS easy to calculate the total or partial tensions. It 
may be worth while to remark, in passing, that these 
four liquids, which we have put in a class by themselves, 
are just those which verify by far the best the generalisa- 
tions of van derWaals; undoubtedly, these liquids are 
to be reckoned as in the highest degree ** normal," as 
their behaviour approaches most nearly that theoretically 
predided. 

In the second of our classes we find a difierent 
behaviour. When chloroform is added to benzene or to 
toluene, the total vapour-tension is less than that result- 
ing from the calculation by the rule of mixtures ; the 
variation reaches a maximum when 100 molecules of the 
mixture contain from 50 to 60 molecules of chloroform ; 
the curve then tends to approach the straight line con- 
neding the points on the axis of ordinates representing 
the vapour. tensions of the pure liquids, pradically coin* 
tiding with it when the number of chloroform molecules 
has passed 80. The depression of the vapour-tension of 
chloroform, caused by the addition of either benzene or 
toluene, is linearly proportional to the concentration only 
in solutions containing less than 20 molecules of either 
hydrocarbon to 100 molecules of the mixture. 

When we consider the partial tensions of these mixtures, 
we see that the same regularity as was observed in the 

* Th\% obeervation does not nem to t>e confirmed in the case of 
tlie partial preiture of nitrobenxene in ita mixture with carbon tetra- 
chloride. This exception, however, I am inclined to attribute to 
experimental errors, whicli made themielvet particularly felt in the 
invcitigation of miiturea of thete two liquidt. Indeed, if the allow- 
ance be made for the degree of accuracy which we have decided the 
method capable of yielding, it will be seen that the discrepancy can 
be made to disappear almoat entirely. 



first class of liquids is found here, but only for toluene 
and benzene; the partial tension curve for chloroform 
resembles closely in its contour that for the total tension 
of the mixture. The departure of chloroform from the 
straight line is not, however, very marked. 

In the third class of mixtures we meet with a difierent 
behaviour. When benzene or toluene is added to cafhoo 
tetrachloride, we observe that the curve of total tension 
follows closely the line conneding the points correspond- 
ing to the vapour-tensions of the mixed liquids until 
towards the abscissae value of 80 ; the curve then com- 
mences to fall, only to rise again, and pass above the 
straight line, when, finally, it changes its diredion to 
fall upon the axis of ordinates at the point standing for 
the vapour-tension of the pure hydrocarbon, benzene, or 
toluene, as the case may be. As is seen, the curve has 
three turning points. The curve of the partial tension of 
the carbon tetrachloride resembles in every detail, in each 
mixture, that of the total tension ; but once more it is 
observed that the partial pressure curve for the hydro- 
carbons is, so to say, a straight line. It is truly a 
remarkable result that in the mixtures which have such 
different total tension curves, the curve for these two 
liquids should turn out so simple. There is but little 
doubt that the above instances are sufficient to render 
very probable the sissumption that this behaviour is 
general, and that in all biniarv mixtures made up of 
benzene or toluene, with any other volatile liquid what- 
soever, the same normalitv in the behaviour as regards 
partial vapour-tension of these two hydrocarbons wul be 
found. It is even possible to go a step farther, and claim 
that, inasmuch as in the mixtures of the first class, 
normality of the partial pressure was found in the case of 
each component of the mixture, this normality will per- 
sist in mixtures of the halogen compounds of benzene 
with any other liquids. 

The fad that benzene and toluene possess ** straight 
line " partial pressure curves will enable us to get reliable 
and important information as to the partial pressures of 
other liquids mixed with either of the hydrocarbons, from 
a knowledge of the total pressure of the mixtures ; for all 
that is necessary to do is to draw, in the coordinate 
system adopted in this paper, the total pressure curve and 
a straight line from the point, representing, on the axis 
of ordinates, the vapour-tension of benzene at the tem- 
perature at which the determination has been made, to 
the foot of the opposite ordinate ; the value of any ordinate 
comprised between these two curves gives, then, the 
partial pressure, to a very close approximatioo, of the 
other component of the mixture. 

Furthermore, it is apparent that the partial tensions of 
either chloroform or carbon tetrachloride is the same 
when mixed in the same proportions with either benzene 
or toluene ; the simplicity of the behaviour of the latter 
liquids permits of the free exhibition of the peculiarities 
in that of the former. 

(To be continued). 



Experiments on the RedaAive Power of Pare 
Yeasts : Means for its Measurement. — M. Nastukoff. 
Taking the power of the ferment of champagne as 1*00, 
that of the wines of Portugal is 075, of Saecharomyas 
pastor ianus 0*50, that of 5. apiculatus 0*25, and that of 
the yeast of Brussels beer 0*25.^0. /?., cxxi., No. z6. 



CBkmicalNiws,! 
Not. 1, 1895. f 



Chemical Researches and Spectroscopic Studies. 



215 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 1 
STUDIES OF VARIOUS ELEMENTS. I 

By JBAN SERVAIS STAS. | 

(Ooatioaed from p. 905). 

Oh ike Gasis ustd, — In all my fundamental experiments 
I used none but air, ozyeen, hydrogen, and coal-gas, 
stored for at Utut twenty-fimr hours in large gasometers 
over water free from organic matter, and made alkaline 
with lime or baryta to absorb carbonic anhydride. The 
gasometer used to bold oxygen was one of Pepys*s ; it 
held about z cubic metre ; it was made of copper, and 
would stand a pressure of 5 atmospheres. The gasome- 
ters used for storing air, hydrogen, or coal-gas were bell- 
shaped and properly counterpoised ; they were built of 
galvanised sheet-iron ; they held about 5 cubic metres, 
and were placed in the basement of the large laboratory, 
where the tank of alkaline water was put in winter to 
keep it from freezing. 

All tubes connefting the gasometers to the burner were 
made of lead ; they were long and very flexible, so as to 
yield easily to all requirements ; they were washed suc- 
cessively with ammoniated water, pure water, water 
acidulated with sulphuric acid, and, lastly, with pure 
water, taking care to leave their inner surface damp. 

It was only by the above means that I succeeded in 
obtaining air, oxygen, and hydrog|en completely free from 
sodium. I always found illuminating gas free from sodium 
when taken dire A from the main. 

Oh th€ Air, — I have already explained the methods 
I adopted for obtaining air free from sodium ; I need not 
repeat them. 

On the OxygiH. — The oxygen was prepared by the 
aAion of heat on a mixture of chlorate of poussium and 
r^ oxidg of moHgoHtu, calcined and washed. Before 
letting it into the gasometer filled with alkaline water, it 
was made to pass through three tubulated bottles, the 
first containing a concentrated solution of hydrate of 
potassium, and the other two pumice-stone broken up and 
soaked in a saturated solution of the same hydroxide. 
After twenty-four hours rest, it was free from all trace of 
sodium or potassium compounds. 

On thi HydrogiH, — I have had great difficult in getting 
pore hydrogen, — that is to say, hydrogen burning in pure 
air with a colourlas flamie, and showing neither the so- 
dium line nor any trace of a continuous spedrum. 

I will begin by confessing that I utterly failed to obtain 
hydrogen which would bum with a colourless flame so 
long at I used it as fast as I made it. Therefore hydro- 
gen made by the eledrical decompostion of water, acidu- 
lated with sulphuric acid, in the presence of pure sine 
amalgam to retain the oxygen, did not fulfil this condi- 
tion. It was absolutely necessary to pass it through pure 
hoiling water, to condense the steam in a metallic refri- 
gerator, and to colled and store it for at least twenty- four 
hours over pure water. I will say the same for hydrogen 
prepared from xinc and a xo per cent solution of sulphuric 
acid. However pure the metal, acid, and water might be, 
the resultant hydrogen, when ignited at the end of a 
platinum tube, ^e from dost, which had been raised to 
White-beat and then suddenly cooled, burnt in pure air 
with a reddish-yellow flame, unless it had been passed 
through pure boiling water and then stored over pure 
water. The hydrogen used in all my principal experiments 
was obtained from zinc specially prepared for these re- 
searches. More than 40 kilogrammes of this zinc was used. 
It was freed from all traces of carbon, arsenic, and other 
bodies likely to form compounds when in a gaseous state. 
It was made from pure calamine, and had b^n re-distilled 
in hulk with well^calcined oxide of zinc, to remove all 
traces of carbon, and condensed in a fire-clay retort.* 



* The hydrogen used io tbe bydrocen and air blowpipe wm made 
iron pore csltmine sioc kept melted for eome cine, end well etinvd 
ap with s Ptf ccat of its weight of powdered fated litharge. The 



I faciliuted the produdion of hydrogen by making tbe 
zinc read ion take place in pure boiling water, to which 
was added, little by little, sulphuric aad mixed with an 
equal volume of water saturated with sulphate of coffer^ 
so as to yield a steady current of gas. 

By placing the receiving vessel, sometimes glass but 
genenilly lead, in a bath of water kept running to prevent 
rite in temperature, one can obtain hydrogen free from 
sulphurous or sulphuric acid. In addition to this, during 
my first trials, I took care^ before passing the hydrogen 
into the gasometer, to pass it through a large flask fiUed 
with pumice-stone, broken into very small pieces and 
moistened with a solution of caustic potash, and a second 
large flask filled with small pieces of pumice-stone 
moistened with an acid solution of sulphate of silver. 
Whenever the rate of evolution of hydrogen did not ex- 
ceed 100 litres an hour — and care was taken to keep the 
glass or lead generator at a low temperature — I was un- 
able to deted tbe formation of either sulphate or sulphide 
of potassium or sulphide of silver. 

This hydrogen, when received into the gasometer, and 
tested direaiy after its preparation, even after passing 
through pure boiling water, bums with a slightly luminous 
flame, sometimes slightly yellow, sometimes slightly 
orange or even reddish ; but it is noticeable that, in pro- 
portion as it is left over water made alkaline by lime or 
baryta, so it loses this property until it is entirely deprived 
of it. Notwithstanding the numerous trials to which I 
have subjeded it, I have not succeeded in determining 
the nature of the substance which gives hydrogen the 
property of burning with a slightly reddish flame.* So long 
as the flame has the least yellowish tint, spedrum analysis 
shows the sodium D line in it. In order to guard against 
atmospheric impurities I took the precaution, during my 
experiments, of efleding the combustion of hydrogen in 
an inverted bell-jar holding 20 litres, with a neck the edge 
of which was ground and polished, closed by a flat metal 
lid, which was also ground and polished, kept at a low 
temperature by cold running water. The bell-j]ar, whose 
surface was damp, was filled with air continually re- 
newed from the top, and freed from sodium by the method 
mentioned above. A metal tap was screwed into a hole 
in the centre of the cover, so as to enable me to renew 
the air conveniently, and the tap was pot into dired com- 
munication with the domed gasometer filled with purified . 
air. I was thus able to satisfy myself that the colouring 
of the hydrogen flame was as often due to the surround- 
ing air as to the hydrogen itself, and that this latter case 
occurs always when one tries to bum the gas as soon as it 
is made. 

In pure air and complete darkness, pure hydrogen — 
issuing from a clean platinum burner — ^burns with a flame 
so devoid of brilliancy, so little luminous^ that I was often 
obliged to put a piece of platinum wire in it in order to 
see it. The invisibility of the hydrogen flame is further- 
more shown by the introdudion of oxygen, and even of 
pure air. Thus when the height of the flame is diminished 
one-half by the presence of oxygen, tbe hydrogen becomes 
iHcandesceHt^Xhat is to say, luminous — ^when burning, 
and one notices a deep and very pure blue light, always 
supposing that the air and oxygen supplied are free from 
sodium. If the hydrogen or the air show traces of so- 

alloy of rioc and lead made that ia free from all trace of carbon ; 
with a 10 per cent lolation of tnlphonc acid it givea off with great 
eaie hydrogen, which, after remaioiof twenty-four hoara in a eaao- 
meter in contaA with alkaline water free from organic nuttert, boms 
in pore air with a colonrleaa flame. Having atcertained that hydro- 
Sen tet free 1^ the aAion of cine and lead on dilate solpharie acid 
wat, by remaining over alkaline water, entirely deprived of the pro* 
perty of bomiog with a tlightly lominoat flame, I henceforth nte4 
only hydrogen prepared in thit manner in the hydrogen aad air blow- 
pipe. Bat in thit case I have alwaya interpoted a glata bottle, 
za Htret capacity, with two ttopcocka filled with tmail piecea of 
pamice-ttone moituned with a strong eolation of cauttic potath, and 
a coanterpoited zinc-domed gatometer, i cnbic metre capacity, 
charged with baryta water, between the leaden flask with stopcocks, 10 
wbico tbe gat was prodnced, and the barner oted to bum it. 

* For researches made on this tabjea, tee Notb(Chbm. Nbws, 
vol. IzxiJM P« 190). 



2l6 



DeUrminatioH of Selenious Acid by Potassium Permanganate. {^"JlSJfJJiSr** 



diuro, the light is a pale and slightly greeniBh blue. I 
have already mentioned that as soon as hydrogen is 
brought to incandescence, platinum melts in it, and spec- 
trum analysis of the flame shows a conttHuous spedrum. 
On increasing the volume of oxygen, so as to reduce the 
flame to about four-fifths of its height, the blue colour is 
not increased — on the contrary, it appears diminished ; at 
the same time the continuous spedrum gains in clear- 
ness ; one sees indications of the appearance of lines ; 
but in spite of all eflbrts it wsts impossible for me to 
determine their position in a spedrum which, I repeat, was 
too strongly luminous, 

I did not succeed in getting hydrogen to bum in an 
excess of oxygen by the method I employed ; every time 
I supplied oxygen sensibly in excess of half the volume 
of hydrogen, combustion started in the platinum nozzle 
and from thence extended to the pipe of the burner itself, 
which, although of platinum, began to melt. I consider 
the combustion of hydrogen in a sensible excess of oxygen 
to be impradicable with the blowpipe used by Mr. G. 
Matthey, even under a pressure of two atmospheres. 

(To be continned). 



THE DETERMINATION OP SELENIOUS ACID 

BY POTASSIUM PERMANGANATE.* 

By P. A. GOOCH and C. P. CLEMBNS. 

Thb fad that sulphurous and tellurous acids may be 
oxidised quantitatively by a sufficient excess of potassium 
permanganate suggests naturally the application of the 
same general method to the determination of selenious 
acid. It is the objed of this paper to record the results 
of experiments in this diredton. 

Brauner {youm, Cktm, Soc, 1891, p. 238) found that 
in the adion ot the permanganate upon tellurous acid, 
whether in a solution acidified with sulphuric acid or 
made alkaline by caustic soda, the redudion of the per- 
manganate does not proceed to the lowest degree of 
oxidation, the tellurous acid being unable to reduce the 
higher hydroxides of manganese which separate. In 
employing the readion quantitatively it is necessary, 
therefore, to add the permanganate in distind excess, and 
then to destroy the surplus by means of standard oxalic 
acid added to the solution acidified with sulphuric acid, 
subsequently determining the excess of oxalic acid m the 
warmed solution by addition of more permanganate. 
The difference between the amount of permanganate ac- 
tually used and that required to oxidise the known 
amount of oxalic acid introduced should naturally be the 
measure of the tellurous acid aded upon. Brauner found, 
however, an error in the process, by no means inconsider- 
able, due to the decomposition of the permanganate out- 
side the main readion. In a subsequent paper from this 
laboratory (Gooch and Danner, Amir, yourn. ofSciince, 
xliv., 30Z) it was shown that if the precaution is taken to 
restrid the amount of sulphuric acid present in the solu- 
tion when the permanganate ads, the secondary decom- 
position involving loss of unutilised oxygen is kept 
within narrow bounds. In our work upon the oxidation 
of selenious acid we have followed the suggestions 
gained in the treatment of tellurous acid by Brauner*s 
method. 

The selenium dioxide which we employed was prepared 
from so-called pure selenium by dissolving the element in 
strong nitric acid, removing the nitric acid by evaporation, 
treating the aqueous solution with barium hydroxide to 
throw out any selenic acid formed in the oxidation, eva- 
porating the solution to dryness, and subliming and re- 
subliming the residue in a current of dry air until the 
produd was white. The oxide thus prepared was weighed 

• Contributions from the Kent Chemical Laboratory of Yale Col- 
leee. From the A miricaH Journal 0/ Science^ vol. I., July, itJgj. 



out for individual experiments or was dissolved in m 
standard solution from which definite portions were drawn 
for use. 

In the first series of experiments, the results of which 
are recorded in Table I., the selenium dioxide was dis- 
solved in xoo cm.* of water, zo cm.* of sulphuric acid 
of half strength were added; an approximately deci- 
normal standardised solution of potassium permanganate 
was added until the cbaraderistic colour predominated 
over that of the brown hydroxide deposited during the 
oxidation ; oxalic acid in solution of known strength was 
introduced until the excess of permanganate had been 
destroyed and the insoluble hydroxide dissolved ; and, 
finally, after heating the solution to about 80^ C, more of 
the permanganate was added to the colour readion. The 
final volume varied from 250 cm.* to 350 cm.*, so that 
the sulphuric acid (absolute) present varied from about 
5 per cent at the start to from x} to a per cent at 
the end. 

When the permanganate is first introduced into the 
acidified solution the colour vanishes, leaving a clear 
colourless liquid; but as more is added the solution be- 
comes vellow, and deepens gradually in colour to a 
reddish-brown, until turbidity, due to the deposition of a 
brown hydroxide of manganese, ensues, and finally the 
cbaraderistic colour of the permanganate is plainly dis- 
tinguishable. The exad point at which precipitation of 
the manganic hydroxide negins depends upon the dila- 
tion, acidity, and temperature of the solution. In ex- 
periments (x) and (2J the permanganate was added to the 
cold solution at the first, but the liquid was heated after 
the addition of oxalic acid, and before the final titration 
with the permanganate. The remaining determinations 
of the series were made in solutions kept hot throughout. 



SeO, 
taken. 
Grm. 
(x) O'XOOO 

(a) o'looa 

(3) 0-0997 

(4) 00999 

(5) O'XOOO 

(6) O'XOOO 

(7) O'lOOI 

(8) o'aooi 

(9) 0x997 
(xo) 0x997 
(XI) 0-5x78 
(xa) 0-5197 



[Se- 

Oxygen 
eauivalent 
ot perman- 
ganate uied. 
Grm, 
0*03026 
0*03038 
0-02634 
0*03568 
0*02536 
0*03226 
004455 
005448 
o'052X9 
0*052x5 
o'X32X5 
o'X4X05 



Table I. 
791. 0-16.] 




Oxygen 






equivalent 






to oxalic 


SeO. 




acid naed. 


found. 


Brror. 


Grm. 


Grm. 


Grm. 


0'0I57X 


O'ZOZO 


0*00x04- 


0*0x578 


o'zox4 


o'ooxa+ 


0'0ZX82 


o*zoo8 


o*ooxx + 


0*01 X 22 


01004 


0*00054- 


o'oxo77 


o*ioia 


000x34- 


o'ox765 


0*10x5 


000154- 


02992 


o*zoz6 


0*00x54- 


0*02543 


o'aoz8 


000174- 


002318 


o'aoi4 


000174- 


0-023x8 


o*aoix 


0*00x44- 


o'0572X 


o*5ao3 


o'ooa54- 


006541 


0*5353 


003554- 



An examination of these results develops the fad that 
the adion proceeds regularly in the main under the con- 
ditions of experimentation, but that there is an apparent 
waste of permanganate in the process. It was observed 
that the addition of a little permanganate beyond the exadt 
amount necessary to produce the end-readion occasioned 
the precipitation of manganese hydroxide, evidently, ac- 
cording to Quyard's readion, by interadion between the 
fermanganate and the manganous sulphate present, 
lainly the amount of sulphuric acid present, which we 
kept purposely low to obviate the spontaneous decom- 
position of the permanganate, was not sufficient to pre- 
vent the ultimate formation of the hydroxide at the 
temperature of adion. The natural inference is that the 
difficulty in the determinations may have been due rather 
to an interference with the colour readion at the end of 
the oxidation process, due to the incipient tendency of 
the permanganate to ad upon the manganous salt, than 
to dired loss of oxygen from the permanganate. If thie 
is true, the obvious and simple remedy should be found 
in eifeding the oxidation of the oxalic acid at the end of 
the process at a temperature so low that the inclination 



Cbshical NlWt, I 
Hov, I, iSgs* f 



Estimation of the Halogens in Mixed Silver Salts. 



217 



of the permanganate and manganoas Bulpbate to interad 
•hall be diminished. Table II. contains the record of 
experiments in which this precaution was taken. The 
entire process of oxidation, which was otherwise similar 
to that of the previous experimeots, was brought about 
between the temperature of 75** C. at the beginning and 
50^ C, or even a little less, at the end. The end-rea^ion 
was in every case sharp, and the final colour was perma- 
nent for several minutes at the least. 





Table II. 








Ozygea 


Ozysen 








equivalent 


equivalent 






8eO, 


of permen- 


to oxalic 


found. 




taken. 


ganate need. 


acid used. 


Error. 


Grm. 


Grm. 


Grm. 


Grm. 


Grm. 


(13} 0*XOOO 


0*03506 


0*02065 


0*I00X 


0*OOOX + 


(14) O'lOOO 


0*035x9 


0*02073 


0*X004 


0*0004+ 


(25) 0*1000 


0*03706 
0*03853 


002255 


o*xoo7 


0*0007+ 


(16) O'XOOO 


0*02422 


0*0994 


o*ooo6- 


(17) O'XOOO 

(x8) 0*2000 


0*035x2 


0*02065 


o'xoo5 


0*0005 + 
0*0006— 


006x24 


0-03256 


o*X99i 


(xg) o*aoxx 


0*06069 


003x77 


0*2008 


0*0003 - 




0*06072 


0*03x77 


0*2010 


0*0006+ 


(ax) o*ao2o 


0*06083 


0*03x85 


0*20x2 


o*ooo8- 


(22) 0*2038 


0*06106 


0*03x85 


0*2028 


0*00x0- 



These results are evidently an improvement upon those 
of the first series of experiments, and are fairly satisfadory 
so far as concerns the estimation of the amounts of sele- 
nium dioxide discussed. The determination of large 
amounts of selenious acid by this method is somewhat 
less advantageous than it would be if the redudion of 
the permanganate proceeded farther in the first adion. 
One hundred c.c. of a standard solution is as much as can 
be conveniently handled in a single process of titration, 
and that volume of decinormal permanganate (which is 
about as strong as the standard solution should be when 
accurate work is expeded) is capable of oxidising about 
0*25 grm. of selenium dioxide. 

The process which we recommend consists, in brief, in 
the addition of standard potassium permanganate to the 
solution of selenious acid containing not more than 5 per 
cent of its volume of strong sulphuric acid, the introduc- 
tion of standard oxalic acid until the liquid clears, 
and the titration of the excess of oxalic acid by 
permanganate, at a temperature not much exceeding 50^ 
or 60^ C. The permanganate and the oxalic acid should 
be standardised under similar conditions of itcidity and 
temperature, and for a standard of final reference we 
prefer pure crystallised ammonium oxalate. 

We have made experiments in which the initial oxida- 
tion of the selenious acid was made in alkaline solution, 
bot inasmuch as the amount of permanganate required 
for the oxidation is about three times as great as that 
needed in the acid solution, the treatment in alkaline 
solution is pradically inferior. 



THE ESTIMATION OF THE HALOGENS IN 

MIXED SILVER SALTS. 

By F. A. GOOCU and CHARLOTTE FAIRBANKS. 

Known methods for the estimation of chlorine, bromine, 
and iodine in mixed silver salts depend either upon the 
redodion of the salts to metallic silver or their conver- 
sion to a single definite silver salt. The old but by no 
means ideal methods for the determination of chlorine 
and bromine in mixed silver chloride and bromide, by re- 
dudion of the salts to silver in hydrogen at high temper- 
atures or conversion to silver chloride in an atmosphere 

* Contributions from the Kent Chemical Laboratory of Yale Col- 
lege. From the Ammcan Journal 0/ Scitttc*, vol. i., July, xSgs* 



of chlorine, are typical. Perhaps the best of all are the 
eledrolytic method of Kinnicutt {Am, CA#m. yoiif.,iv., 22) 
for the redudion of the fused chloride and bromide, the 
battery process of Whitfield {Am,Cksm,youm.,viii,,^2i)t 
which involves the eledrolysis of the solution of the silver 
salts in potassium cyanide, and the method of Maxwell- 
Lvte (Chbu. Nbws, xlix., 3), according to which the 
silver in the cyanide solution of the silver salts is thrown 
down by potassium iodide and sulphuric acid. Even in 
these processes there are points against which objedioa 
may be raised with reason. Thus, in the processes of 
Whitfield and Maxwell -Lyte, it is next to impossible to 
secure complete and speedy solution of the aried silver 
salts in potassium cyanide without recourse to interme- 
diate washing and treatment with nitric acid; and in 
Kinnicutt'a method, which has been applied only to the 
analysis of the mixed chloride and bromide, difficulty is 
found in the speedy removal of all sulphuric acid from 
the spongy mass of silver formed in the redudion. 

We have tried many experiments with a view to sim- 
plifying the analysis of the mixed silver salts. Ignition 
with mercuric cyanide according to Schmidt's method for 
sulphides {Ber. d. Chim, OmU., xxvii., 225) ; treatment 
with cuprous chloride dissolved either in ammonia or in 
hydrochloric acid ; the adion of ferrous oxalate dissolved 
in potassium oxalate, Eder's reagent (B#r. d, Chim. 
Oes.f xiii., 500) ; treatment with chromous chloride or 
chromous acetate; contad with powdered magnesium 
under dilute acid ; and many other plans of adion with 
powerful reducers have failed to yield analytical results 
comparable with those of the known methods. Hydrogen 
sulphide, dry or moist, and ammonium sulphide attack 
the halogen salts of silver with varying intensity, the 
chloride very easily, the bromide with less ease, and the 
iodide most difficultly — as might be predided from a 
knowledge 01 the thermal values involved in the readions. 
A current of hydrogen sulphide charged with ammonium 
sulphide effeds the complete conversion of silver chloride 
to silver sulphide at a temperature below 200^ C, ; but we 
have never succeeded in securing absolutely complete 
conversion of the bromide to the sulphide by similar 
treatment, even at much higher tem|>eratures, and the 
iodide resists conversion more obstinately than the 
bromide. Nor have we been able to find conditions under 
which the chloride may be converted while the bromide 
and iodide remain unattached. In a study of the conditions 
best adapted to the redudion of silver salts eledrolytic- 
ally, we have obtained results which point to advantageous 
modifications of the methods heretofore known. We find 
that the treatment of the fused salts may be simplified, 
made more accurate, and extended to mixtures containing 
silver iodide. 

In Kinnicutt*s process the difficulties lie, first, in the 
impossibility of destroying the paper upon which the 
silver salts have been colleded and washed, without 
affeding the redudion of the salts ; secondly, in the ob* 
stinacy with which the spongy silver holds the sulphuric 
acid during washing; and thirdly, in the tendency of the 
chlorine liberated, when a chloride is present, to attack 
the eledrodes. 

Upon the first point nothing need be said ; the difficulty 
is obvious and well known. As to the second source of 
error, our experience shows that rapid washing is not 
sufficient to remove the sulphuric acid included in the 
reduced silver, even when excessive amounts of wash- 
water are used ; but that a considerable time is indispen- 
sable for the escape of the acid from the silver to the 
wash-water by diffusion. In several cases we have found 
errors, ranging from a single milligramme to six or seven, 
due to inclusion of the acid in residues which had been 
washed freely but rapidly, and which even after ignition, 
yielded slowly hot- water extrads, which gave the test 
for a sulphate by barium chloride. 

The results of some experiment made to test the effed 
of the halogens set free in eledrolysis are shown in the 
accompanying table :~ 



3i8 



Estimation ofihe Halogens in Mixed Silver Salts. 



fCHBMlCAL NbwS, 

I Hov. I, 1695. 



BltArolyte 

iSc.m.a of 

H«S04(M per 

cent) with 

tbe ■obttance 

samed. 



Change in 
weight of 
Strength of Time the con- 
current io in taining 
ampteca. hoare, 



Change in 

weight of Connec- 

wire tion of 

electrode, crucible. 



crucible. 
Grm. Grm. 

Z7gnn.KI 0*46—0*25 24 o'oooo coooo Cathode 
I ,, KBr o'5o 0*18 35 O'OOOO 0*0000 Cathode 
X „ KCl 0*48—0*18 26 00008- 0*0001 - Cathode 
0:5 M HCl — — ♦o'ooog- 0*0000 Cathode 

0:5 H HCl 0*3 48 0*0004- 0*0004+ Anode 

* Platinnm teeted for and fonnd in lolntion. 

So it appears that while neither bromine nor iodine at- 
tacked the platinum perceptibly under the conditions of 
the experiments, though set free in abundance, an appre- 
ciable amount of the metal did dissolve under the adion 
of chlorine. Moreover, the solubility seems to depend 
chiefly upon the area of surface exposed, and not upon 
the eledric polarity. The metal dissolved was re-precipi- 
tftted by the aaion of the current only in the experiment 
in which, by reversing the diredion of the current, and 
thus making the area of the anode large while that of the 
cathode was diminished, a corresponding increase of 
current density upon the cathode was brought about. It is 
obvious that, under ordinary conditions of eledrolytic re- 
duaion, the solvent eifed of the chlorine upon the platinum 
will naturally produce an apparent deficiency in the weight 
of silver reduced. 

These sources of error in the eledrolytic redudion of 
the fused silver salts we have endeavoured to overcome. 
The d anger of change in the constitution of the salts 
during preparation for weighing we avoid by colleding 
them upon asbestos in a perforated crucible instead of 
upon paper; but in order to secure perfed eledrical con- 
dudivity throughout the mass of silver salts subsequently 
colleAed, dried, and weighed, we place a disc of perforated 
platinum foil upon the prepared felt of asbestos. In this 
way perfea elearical contad is obtained, though the ra- 
pidity of filtration is somewhat impaired. The diic also 
aerves the useful purpose of preventing the disturbance of 
the felt by the gas evolved from the walls of the crucible 
In the eledrolytic process.* When the silver salts have 
been colleded, washed, dried, and weighed, their fusion is 
effeded by placing the capped crucible upon an anvil and 
direding the flame of a small blowpipe with care upon 
the mass from above. The anvil keeps the crucible cool, 
and tends to prevent the soaking of the asbestos with the 
fused silver salts, which would be disadvantageous in the 
washing process which follows the redudion. A rubber 
band, cut from rubber tubing of suitable diameter, is ad- 
Justed so as to cover the jundion between the cap and 
crucible and make a water-tight eledrolytic cell. When 
the eledrolytic redudion is finished the band and cap are 
removed, the crucible is put upon the pump, the liquid is 
drawn through, and the precipitate washed in the usual 
manner. 

It is obvious that the difficulty of washing out the sul- 
phuric acid from the reduced silver may be avoided if it is 
possible to substitute for the sulphuric acid an eledro- 
lyte which, even if it were not easily removed by washing, 
should be volatile at gentle heat without affeding the 
silver; and the danger arising from free chlorine may be 
obviated by taking care to have the chlorine absorbed by 
the eledrolyte as soon as it is liberated. We find that 
25 per cent alcohol containing a tenth of its weight of 
oxalic acid meets all the conditions for the eledrolytic 
redudions of the mixed chloride and bromide of silver. 
Such a solution, while possessing sufficient condudivity, 
absorbs the free chlorine to such an extent that, as we 



* This device hai been luggested by Puckner [Joum. Am. Chem. 
Soc.t 1893. 7x0) for holding down the asbeitot in an ordinary filtra- 
tion, and It no donbt of value when suitable asbestos is not at hand. 
A fairly good asbestos properly prepared, and deposited upon a per- 
forated surface in which the holes are sufficiently numerous— best, as 
numerous as can be— does not. however, tend to rise during a filtra- 
tion 10 long as the iuAion-damp is in aaion.— F. A. O. 



have found experimentally, no perceptible solvent adion 
takes place upon the platinum, and nothing remains in 
the silver reduced under such a solution, which is not 
volatile at gentle heat without affeding the weight of the 
silver. 

In the test-experiments recorded in the accompanying 
table known amounts of silver chloride and bromide were 
precipitated, colleded, washed, dried at 150** C, and 
weighed in the filtering crucible, provided as usual with a 
layer of asbestos, which was in this case covered with the 
perforated platinum disc. The cap was put in place, the 
crucible set upon an anvil, and the salts fused with a 
blowpipe flame in the manner described. The rubber 
band was adjusted, the crucible nearly filled with the 10 
per cent solution of oxalic acid in 25 per cent alcohol, 
and the currsnt passed in the usual manner, the crucible 
serving as the negative eledrode. When the redudion 
was judged to be complete the band and cap were re- 
moved, the crucible set upon the pump, and filtration of 
the liquid and washing of the residue carried out as 
usual. Finally the crucible, cap, and residue were ignited 
at a very low red-heat and weighed. The entire treat- 
ment was repeated until the constant weight of the resi- 
due showed that the redudion was complete. 



LgCl taken. 


AgBr taken. 


Ag calculated 


Ag found. 


Error. 


Grm. 


Grm. 


Grm. 


Grm. 


Grm. 


1*0608 


— 


0*7985 
1*0823 


07990 


0*0005 + 


1*4380 


— 


1*0823 


O'OOOO 


09998 


— 


07525 


0*7522 


0*0003— 


— 


0*9959 


0*5721 


0*5723 


0*0002+ 


— 


0-9979 


0*5731 


05732 


00001 + 


10044 


0*4988 


1*0426 


I 0422 


0*0004— 


0-4933 


0*4966 


0*6559 


0*6568 


0*0009+ 



The manipulation of the method is very easy, and the 
results show that it is capable of yielding accurate results. 
The current ranged from 0*5 to(o*25 ampere, and for con- 
venience the process was continued over night, though 
the redudon of amounts such at we treated is usually 
complete in six or seven nours. 

Unfortunately this process, which works so well with 
the mixture of chloride and bromide, is not applicable to 
the redudion of silver iodide or to mixtures containing it. 
Experiment proved that the iodine set free in the eledro- 
lysis works over and over again upon the spongy silver, 
constantly regenerating silver iodide to a greater or less 
degree. As the result of many attempts to destroy the 
liberated iodine without inroducing anything objedionable 
into the solution, we finally settled upon a mixture made 
by neutralising two parts by volume of ordinary (40 per 
cent) acetic acid with ammonia, adding one part of am- 
monia, one part of alconol, and one part of aldehyd (75 
per cent). Such a solution we found to work very well 
on the whole, but as the redudion progresses it frequently 
happens that a deposit of white ammonium iodate forma 
upon the anode, which introduces too great resistance to 
the current. This deposit of iodate is, however, easily 
removed from the eledrode by dipping it into hot water. 
Whenever the solution is so exhausted that free iodine 
begins to appear, the liquid should be carefully decanted 
and replaced by fresh ; and before the operation is ended 
the decanted solutions and the washings of the eledrode 
should be filtered throngh the crucible and the residue 
submitted again to the adion of the current, to make it 
certain that loosened particles of silver or silver salt, 
possibly poured off or removed on the eledrode, shall not 
be lost nnally. The necessity of keeping the process 
under occasional supervision renders it undesirable to con- 
tinue the adion over night. In some cases of prolonged 
adion without attention, we have noticed the formation of 
gummy carbonaceous matter, which could not be subse- 
quently removed without the application of a degree of 
heat which might endanger the platinum in contad with 
the reduced silver. Many of the experiments recorded 
in the following table were completed within stvea 
hours with a current not exceeding 0*5 ampere. 



OBBifiCAt. Msiri, I 
Nov. 1, 1895. I 



The Radial Cursor. 



219 



takHB. 
Gnn. 

0-477? 
0*6096 

06774 



AcBr 
tans. 
Gnu. 



Agl 
taken. 
Grm. 



0*9969 

2-3703 



0-5035 
Z*0020 
0*4939 
— 0*5000 



0*4984 
09998 



1*0613 
Z*062I 

1*0140 
i*aoi2 
1*5031 

0*6561 
05304 



Ag 

calcQlated. 
Grm. 
03596 
0*4588 
0*5098 
0*5727 
07872 
0*4878 
0*4882 
0*4661 
0*5521 
0*69x0 
06653 
1*3285 
06734 
0*5310 



Ac 




foond. 


Brror. 


Gmu 


Gnn. 


0*3591 


0*0005- 


04591 


0*0003 + 


0*5099 


0*00014- 


0*5726 


0*0001- 


07875 


0*00034- 


04877 


0*0001- 


tt^ 


0*0007- 
0*000x4- 


0*5530 


0*00094- 


0*69x4 


0*00044- 


0*6653 


0*0000 


1*3283 


0*0002- 


0*6733 


0*0001- 


05316 


0*00064- 



These retulu show that the process affords an acctirate 
redoAion of the chloride, bromide, and iodide of silver 
and mistures of these salts* When the problem concerns 
the redudion of the chloride and bromide only, we give 
the preference to the redudion in alcoholic oxalic acid as 
being the simpler process. The latter process we have 
also applied snccesmly on a larger scale to the recovexy of 
the aih^ in chloride residues. 



PROCEEDINGS OF SOCIETIES. 

PHYSICAL SOCIETY. 
Ordinarf MitUng, Oetobir 25M, 1895. 

Mr. Walter Baily, Vice-President, in the Chair. 

Prof. J. Pbrrv read a paper by himself and Mr. H. F. 
Htmr on the ** DiVilopmtnt of Arbitrary Punctions,^* 

Daring the discnssion on Prof. Henrici's psper (April 
i3tb, i^). oxie of the antbors described a graphical 
method of developing snv arbitrary fundion in a series 
of other normal forms than sines and cosines, such as 
Bessels or sonal spherical harmonics. The method con- 
sisted in wrspping the curve which represents the funAion 
round a specially-shaped cylinder, not circular, and pro- 
jeAing this curve into a certain plane. Many months 
were wasted in finding with great exaAness a sufficient 
number of co-ordinatei of the trace of the cylinder suit- 
able for a Zeroth Bessel development. The labour, how- 
ever, was unnecessary, since the co-ordinate most trouble- 
some to calculate is not really needed, the projedion 
only taking place in one direAion. To develop any 
arbitary funAion of x (say y) in normal forms, the real 
difficolty consists in finding the value of an integral, such 



/' 



^.Q {x).djti 



where Q (x) is some tabulated fundlon. If now, x is 
another tabulated fundion, which is the integral of Q (jt), 
the required integral is— 



/' 



i". 



If the values for y for twenty-five equidistant values of x 
are known, from xso to x^a, I^t the corresponding 
values of jr be tabulated, and let a curve be drawn with 
the values of y as ordinates and the values of m as 
abscisic ; the area between the axis of m and this curve 
gives the value of the integral required. The authors 
give four tables containing the abscissae for the four fiist 
teims in the development in Zeroth Bessels. They have 
tested the method by applying it to the calculation of a 



known fundion in terms of sonal spherical harmooics, 
and the asreement between the true value of the coeffi* 
cients and those found is very satisfadory. 

Prot Hbnrici said the method was a new departure, 
since in the place of an instrument of complicated desigOt 
the authors only used a planimeter and pencil and paper, 
and obtained the same degree of accora^. The fad that 
the series employed to test the method consisted of a 
finite number of terms seemed to him an objedion. Prof. 
Carl Pearson had, in a recent conversation, informed bios 
of a method for the development of fondions which hm 
(Prof. Pearson) had recently discovered. This method 
was not, however, so simple, at least in most cases, as 
that of the authors. 

Prof. MiNCHiN thought it would add to the intelligibility 
of the paper if it were stated that the method was similar 
to that employed when expanding in terms of a Fourier 
series or in spherical harmonics. In these cases ^ou 
have a fundion which, when multiplied by other fundions 
of diffSerent orders, kills all the terms except one. Graphic 
methods ought, in his opinion, to be very much oftener 
employed, and he considered that there was no problem in 
physical mathematics of which the solution could not be 
obtained by graphic methods. He would like to know 
if Prof. Perry had obtained a graphic method of calcu- 
lating Bessels. 

Mr. Trottbr agreed with Prof. Miochia as to the 
negled of graphic methods. He regretted that Prof. 
Perry did not continue to consider the method as the pro- 
jedion from a cylinder, as he had found the methoa of 
wrapping curves round a cylinder most useful. 

Prof. Pbrrt, in his reply, said he had adopted the ex« 
pansion they had employed under the impression that the 
test was a particularly severe one. He had not discovered 
a graphic method of calculating Bessels. The reason 
they gave up the cylinder was the immense labour involved 
in calcttlating the y, co-ordinates of the trace, which 
would afterwards be of no use in the development of the 
fundion. 

Mr. F. W. Lamchbstbr read a paper on <* Thi Radial 
Cursor: a Niw Addition to thi SUdi-ruU.'* 

The ordinary form of slide*rule enables calculations to 
be made which involve multiplication and division ; also 
involution and evolution where the indices are integers. 
The radial cursor allows of the solution of problems in 
which fradional indices occur; for example, in questions 
involving the adiabatic expansion of a gas, where an ex- 
pression of the form pv" m const, has to be dealt with, 
and where y is not an integer, nor is it constant for all 
gases. In this case it is necessary to provide some ready 
means of dividing the scales on the rule and slider propor- 
tionally to the value of y, which corresponds to the divi- 
sion and multiplication of the respedive logarithms of 
the quantities dealt with in the proportion of the indices 
of p and V, i.#., 1 and y. This proportionate division of 
the scales is effeded in the new cursor by a radial index- 
arm, which is arranged to swing about a stud fixed to a 
sliding bar running m guides at right*angles to the rule. 
All readings are taken at the points of intersedion of a 
line on the radius arm and the edges of the slide. The 
distance of the pivot on which the radius-arm turns from 
the slide, snd therefore the value of the index employed, 
is read off on a scale fixed to the transverse bar. 

Mr. C. V. Boys said that owing to the kindness of the 
author be had been able to try the cursor snd had found 
it of great service in dealing with questions of adiabatic 
expansion. The new addition to the slide rule suflbrs 
under the same disadvantage as the mle itself, namely, 
that a verbal or written description seems so very much 
more complex than is the adual operation when using the 
rule. The author's device might be described as an india- 
rubber slide- rule, for it performed the fundion of a slide- 
rule, in which the graduations of the slide were made on 
indiarubber, so that the ratio of the length of the scale on 
the rule to the length of the scale on the slide might be 



220 



Notices of Books. 



i CBBmCAL NftWtf 



altered at will, and thus involution and evolution with 
fradional indices performed. 

Mr. Blakbslby asked how powers less than unity were 
dealt with. 

Prof. S. P. Thompson and Mr. TROtTBR expressed 
their admiration, for the author's method of ** stretching " 
the scale. 

. Mr. BuRSTALLsaid he had attempted to apply a similar 
method to the Fuller rule, but did not succeed, since in this 
mle there was only one scale. He hoped the author's 
method coold be applied in a form such that a greater 
accuracy than z in 300 could be obtained. 

Mr. Bourne thought the fad that the point of inter- 
■eAion of two lines inclined at an acute angle had to be 
read was likely to limit the accuracy. 

The author having replied, the Society adjourned till 
Hovember 8th. 



NOTICES OF BOOKS. 



A Laboratory Manual of Organic Chemistry} a Com- 
pendium of Laboratory Methods for the Use of 
Chemists, Physicians, and Pharmacists. By Dr. 
Lassar • CoHN, Professor of Chemistry in the 
University of Konigsberg. Translated, with the 
Author's sandion, from the Second German Edition by 
Albxandbr Smith, B.Sc, Ph.D., Assistant Professor 
. of General Chemistry in the University of Chicago. 
Small 8vo, pp. 403. London and New York: Mac- 
millan and Co. 1895. 
Thb work before us is not one of those manuals of che- 
mistry, organic or inorganic, which during the last few 
years have become almost painfully numerous. Dr. 
Alexander Smith is quite justified in saying that it ■* covers 
a field not previously occupied," and that it ** does not 
take the place of any of the text-books of organic chemis- 
try, but bears towards them the relation of an almost in- 
dispensable complement." It expounds the method used 
in the laboratory, whether in original research or in veri- 
fying results already obtained. 

The work consists of two parts, a general and a special. 
The former treats of baths (for the regulation of tempera* 
tures) ; of crystallisation and dialysis ; of decolourising 
liquids ; of distillation, whether ordinary, fraAionated, dry, 
or in vacuo ; of drying ; of extraAion ; filtration ; of the 
determination of melting-points ; of molecular weights ; of 
work in sealed tubes ; and of sublimation. 

The special methods include condensation, the prepara- 
tion of diaxo- bodies of esters ; fusion with caustic alkalis ; 
the preparation of halogen compounds and of nttro- 
derivatives ; oxidation ; reduAion ; the preparation of 
salts ; saponification ; the preparation of sulphonic acids ; 
and remarks on ultimate organic analysis. We note the 
remark that in the case of methylene*di-^.toluidine the 
Kjeldahl method gives the nitrogen 3 per cent too low, 
whilst the Will-Varrentrapp method gives a result in ac- 
cordance with the theoretical composition. 

We think that both teachers and students of organic 
chemistry will fird this book a most satisfadory guide to 
research. 



Quantitative Chemical Analysis, Adapted for Use in the 

Laboratories of Colleges and Schools. By FrankClowbs, 

D.Sc, F.LC, Professor of Chemistry in the University 

College, Nottingham, and J. Bbrnard Colbman, Assoc. 

Royal College of Science, Dublin, F.I.C, Head of 

Chemical Department, South-West London Polytechnic 

Third Edition. Post 8vo, pp. 534. London : J. and A. 

Churchill, 1895. 

Thb work of Messrs. Clowes and Coleman has evidently 

given satisfaAion to teachers and students, since a third 

edition is already required. It is admittedly an improve. 



ment on its two predecessors, having been again enlarged 
and enriched with new methods of determination. Addi- 
tional figures have been introduced for the sake of clear- 
ness, and the table of contents has the valuable feature 
of giving references both to paragraphs and pages. 

The bibliography of analytical works will 1^ found of 
value not merely to students, but even to experienced 
praftitioners. 

Part I. treats ably and thoroughly of general and pre- 
liminary operations. 

Part IL instru^ in gravimetric analsrsis, the variona 
methods being placed in the order of their increasing 
difficulty. 

Part in. treats of the volumetric analysis of liquids. 

In Part IV. we find accounts of more complex deter- 
minations, both gravimetric, volumetric, and of a mixed 
charader. Here are included the analysis of ores, of impor- 
tant industrial prodoAs, waters, foods, and various or- 
ganic substances. 

The simple methods of gas analysis are described in 
PartV. 

The onljr eledrolsrtic method is that described for the 
determination of copper. 

Upon spedroscopic quantitative analysis the authors 
do not enter. Methods for the determination of the 
metals of the so-called rare earths have not been inserted. 
In the appendix we find what may be called typical re- 
sults of analyses. 

There are also a series of tables of constants for calcu- 
lating the results of analyses. These, however, seem to 
us by no means preferable to the tables given in ** Roae'e 
Quantitative Analysis," though many of the latter require 
re-calculating, on account of the more accurate deter- 
minations of atomic weights made since 1849. 

On the subjeAs which it includes the work before us is 
an excellent guide. 



The Forces of Nature; a Study of Natural Phenomena* 
By Hbrbbrt B. Harrop and Louis A. Wallis. 
Pp. 160. Columbus, Ohio, U.S.A. : Harrop and Wallis. 
1895. 

Thb work before us is a necessarily sketchy survey of the 
phenomena of the universe, intended, not for the student, 

General or special, but for the general reader who ia 
esirous of a better acquaintance with the cosmos which 
he inhabits. 

In successive chapters, they consider the solar system, 
the earth, the atmosphere, and sound, chemistry fwith 
the strudure of matter), radiant energy, light, heat, 
and adinism, eledricity and magnetism. 

The second part consists of what the authors term 
" disconneAed essays and paragraphs on scientific ques- 
tions." such as the nebular hypothesis, spontaneous com- 
bustion, spontaneous generation, argon and helium, and 
scientific theories in general. 

In most instances the authors may be accepted as 
trustworthy guides ; but in speaking of the dodrine of 
abiogenesis, they overlook the capital part taken in its 
refutation by the illustrious French philosopher whom the 
world has just lost. They accept Huxley's prophecy that, 
in the future, protoplasm will be formed artificially £rom 
its lifeless elements, Thejr are believers in the nebular 
hypothesis and in organic evolution. On the great 
question of chemistry, whether the elements are absolutely 
primordial and inconvertible they give no certain sound. 
They consider the *' canals " on the surface of Mars at 
artificial. The description of snow as rain froxen is 
much more applicable to hail. 

The explanation given of " hypothesis'* as a guess 
having no material foundation cannot be accepted. Most 
of all must we hesitate at the bold assertion that the 
simple laws of mechanics govern ** the complicated func- 
tions of organic life." 

We perceive that the authors announce a companion 



CSBMICAl NlWSt \ 

Hov. 1. 189s. I 



Chemical Notices from Foreign Sources. 



331 



Tolome on the ** Forces of Life," iDcludiog the evidences 
ot organiq erohition. 

Bxawnnation of Watit for Sanitary and Ttchnic Pwr- 
ftn* By Hbmrt Lbfpmaiin, A.M., M.D., Ph.D. 
Tbtrd Edition, Revised and Bolarged. With lUostra- 
tioos. Philadelphia : P. Blakitton, Son, and Co. 1895. 
Tbb aathor classifies waters as rain-water, surface-water, 
sobeoil-water, and deep water; the latter being chiefly 
that obtained from Artesian wells. The instrudions coo- 
ceming taking samples of waters and their analytical ex- 
amination do not differ essentially from those to be met 
with in other manuals of the same kind. The instruc- 
tiona for the determination of saline and organic ammonia 
(known respedively as '* free " and *' albamenoid ** am- 
osooia) are substantially those p;iven by Wanklyn. The 
^eldahl process is described with the remark that it was 
first incceesfnlly applied in water analysis by Drown and 
Martin. Concemmg the Prankland and Armstrong pro- 
cess we read that, *' it requires complex and expensive 
apparatus and special skill, has been shown also to be 
Uahle to inacctiracies, and has not come into general 
«se.** 

For the determination of the nitrogen present as nitrates, 
the aothor recommends Ilosway's modification of the 
Qtiess process. The oxygeuoconsuming power of a water 
mav be determined by Tidy's method, modified by Dapr^, 
nod for the oxygen existing in solution that of Blares is 



ror the determination of phosphates — a point deemed 
nnessential by many chemists, including Wanklyn —Dr. 
Leffmann tesu with molybdenum solution. We are glad 
to find that among the poisonous metals chromium is not 
overfc>oked — a dangerous impurity which may possibly 
occur in industrial localities. We can scarcely accept the 
ipiew that Beggiatoa— commonly called ** sewage fungus " 
—indicates suspended organic matter. It occurs in deep 
springs charged with sulphur and in sulphuretted indus- 
trial waste waters not charged with organic matter. 

The author enters to some extent upon the presence, 
detoAion, and possible effeds of micro-orsanisms ; a sub- 
jeA overlooked in the earlier manuals of water analysis, 
but upon which biologbu and chemists have not yet come 
to a loU and clear agreement. 

The work before us is, however, one which the sanitary 
chemist may with some advantage include in his library 
of reference. 



CHEMICAL 



NOTICES FROM 
SOURCES. 



FOREIGN 



M OTC^AU dccrsat of ttmpsratttro ai • Ceotigradt voltM otharwii* 



Campus Rmdus UMomadaires des Sianca^ di l*AcademU 
des Scimca. Vol. cxxt., No. 16, OAober 14, 1895. 

The perpetual Secretary read a letter signed by the Due 
de la Broolie, of the French Academy, lipoid Delisle, 
of the Academy of Inscriptions and Literature, Ch. Har- 
mite, of the Academy of Sciences, Ambroise Thomas, of 
the Academy of the Fine Aru, and O. Picot, of the 
Academy of Moral and Political Sciences, inviting the 
naembers to be present at a religious ceremony to be cele- 
brated 00 OAober 23rd in the Church of St. uermain des 
P161 in memory of tbose of the members who have died 
since the foundation of the Institute. The service will 
be conduced by the Bishop of Autun. 

The President announced the death of Baron Larry, a 
** free member/* which took place onlOdober 8th. Emile 
Blanchard took occasion to claim lor Baron Larry the 



honour of having been the advocate of conservative snr 

Determination of Argon.— Th. Schlossing, Jun«— (See 
p. an). 

A^ton of Hydrochloric Acid upon Copper. — R. 
Engel. — The decomposition of hydrochloric acid by cop- 
per with the liberation of hydrogen is so slow and so 
inconspicuous that it has been often overlooked. This 
acid, in a solution saturated at 15^ is decomposed by 
copper so rapidly that the liberation of hydrogen mav be 
shown in a ledure. If a little platinum chloride is added 
to the acid the readion becomes tumultuous, but soon 
slackens, so as to be almost imperceptible, though it con- 
tinues for several years. The deoompoeittoa of the hydro- 
chloric acid by copper ceases when the solution contsins 
less than 48*8 to 49 milli-mols. of HCl. Such a solution 
has a sp. gr. of 1*083 <^d ^^ composition HCl-|-xoHaO. 
The aaion becomes extremely slow when the liquid is 
saturated with cuprous chloride. If we pass a current of 
gaseous hydrochloric acid into water in presence of copper 
and cuprous chloride the aftion is rapid. Anhydrous 
hydrochloric acid is always decomposed by copper. 

Action of Potassa and Potassiam Bthylate upon 
Benzoquinone. — Cb. Astre. — The author has isolated a 
compound formed by the union of a mols. of alcohol and 
X mol. of bipotassic quinone. This derivative is interesting 
as being formed in presence of an excess of potassa, which 
seems to indicate that bensoquinone contains only 2 atoms 
of hydrogen capable of being replaced by potassium. 

Combinations of Antipyrin with the Oiphenols; 
Influence of the respective Positions of the Hy- 
drozyls.~G. Patein and B. Dufau.~The diphenols, pyro- 
catechin, resorcin, and hydroquinone behave in diflferent 
manners with antipyrin. The ortho- and para-diphenols 
combine with two mols., but the meta- with one only. 
The fixation is effeded upon one of the atoms of nitrogen 
by the intervention of phenolic hydroxyl, which loses this 
property in proportion as its hydrogen is replaced by a 
metal or a radicle. 



Ziituhrijt fur AnorgOHiuht Cktmii. 
Vol. viii.. Fart 3. 

A Contribution to the Constitution of Inorganic 
Compounds.— Alfred Werner (Second Communication). 
—This valuable paper requires the eight accompanying 
figures. We can merely remark that it is mainly of a 
controversial charaAer, with especial reference to the 
recent memoir of Jdrgensen on the bases of cobalt, 
chrome, and rhodium. 

A further paper, by the same author, discusses the rela- 
tion between the co-ordination and valence compounds. 
Itr is laid down that the fundamental law regulating the 
formation of these elements is the effort of the central 
element to group around itself four radicles. 

Atomic Weight of Tungsten. — Mary £. Pennington 
and B. F. Smith.— The mean value obtained from nine 
determinations ia ■■ x84'9ax, the maximum result having 
been x84'943, and the minimum x84*9oo. The details 
of the experimenu have appeared in the Amaricam 
Chimical jfoumal. 

In another paper on the same subjed, by £. F. Smith 
and £. D. Deai, the mean atomic weigbt of tungsun 
is given •- x84'704- 

Specific Heat of Metallic Tungsten.— A. W. Grod- 
speed and £. F. Smith.— The autbors give the value 
» 6-25, taking the atomic weight of tungsten as 184-921, 
or a 6*243, on the basis of Smith and Dasi*s atomic 
weight. 

Double Tranaposition of Gaseous Bodies. — 
Henryk Ardowski. — This paper (a translation from the 
French^r Flemish ?) requires tbe two accompanying 
figures. Tha law laid down is an extension of that of 



222 



Chemical Notices from Foreign Sources. 



Berthelot—'* If the mixtura of the Trnpoiirt of two com- 
pooad bodies cao ^ve oa doable dccompoiition e produd 
■olid et the prevaiUng tenperatore aod pressure, whilst 
the three other prodods remain saseous, this will always 
tdidlfsr in a solid form outside of this atmosphere." 



BulUUn di la SociStS d^Bncouragtmini four PlnduiMs 
NoHoHoli. Series 4, Vol. a., No. zi6. 

Review of Improvements recently introduced in 
the Industry of Dittillattoo.^L. Lindet.— This bulky 
memoir does not admit of useftal insertion, the rather as 
the improvements concerned largely relate to the menu- 
fadnre of a spirit from beet- root. 

Review of the Progress recently efiedled in the 
Milling Industry.— M. Colson Blanche. — ^We are snr* 
prised at finding the prodndion of meals and flour classed 
among the ** chemical '* indnstriet. 



MEETINGS FOR THE WEEK. 

lloiiDAT,4tb,— Rojrtl lottitotioo, 5.. Qtoerml Mootbljr Mattiiif. 
— » Society of Cbtmicallndottry, 8. ** FUtntioo of Sew- 

age BflBaeot.*' by W. J. Dibdio, F.I.C., F.C.S. 
WaOMBftDAT, 0th.^Society of Public Aoalyett, 8. <* Note on tbe 
Bromine end Iodine Abeorptiooe of Lioeeed 
Oil." by Rowland Williams. ** The Determi- 
nation of Oxycen in Commercial Copper," bv 
Bertram Bloant. ** Mote 00 a Recent Milk 
Caie involving an example of Abnormal Milk" 
and ** Mote on • Filled Cbeeae,'" by R. Bod- 
mer. '* Tbe Compoaition of Condeaaed Milk,** 
by Messra. Peannain and Moor. ** Note on 
tne Oompoaition of Commercial Condenaed 
Milk," by A. H. Allen. " Note on tbe Eatima- 
tion of minute qoantitiea of Metala in Liqnida** 
and ** Note on a Convenient Form of Polari* 
meter for Bxamining Eiaential Oila," by 
f ' Meeara. Budden and Hardy. *' Note on a aeriea 

of Analyaea of a Private W^ter Sopplyif by 
B. Rneeell Budden. 
TBUiaoAT, ytlw— Chemical, 8. '* Tbe Temperaturea of Flamee and 
the Acetylene Tbeory of Lomhioeity/' bir Prof. 
Smitbella. ** Tbe AAion of Acidic Oxidea on 
Salta of Hydroxy*acida," byProf.G. G. Hender- 
Bon and D. Prentice. ** Sodium Mitroeoanlpbate, 
and tbe Conttitution of N itrosoaulpbatea," by 
Profs. Divers and Haga. And other papera. 
FaiDAT, 8tb.— >PbyBicaI. 5. ** Tbe Magnetic Field of any Cylindrical 
or Plane Coil,** by Mr. Everett. *' Tbe Latent Heat 
of Volatilisation of Benaene,** by Mr. GrifBtha and 
Miaa Marshall. " Tbe Comparison of Latent Heata 
of Volatilisation,** by Prof. Ramsay and Miaa Mar- 



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I 9ov. 1, 1893. 

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CRBMICAt NBWt, ) 

Kov. 8, 1895. f 



Discussion on Argon and Helium. 



223 



THE CHEMICAL NEWS 

Vol. LXXIL, No. 1876. 



BRITISH ASSOCIATION. 

Ipswich Mebtino. 

Sections A and B (Joint Meeting). 

Discussion* on Argon and Helium. 
The first item 00 the agenda was a paper by Lord 
Raylsigh, Sec. R.S., ** On thi Refraction and Viscosity 
of Argon and Helium,'* His lordship stated that what 
be had to bring forward consisted of little more than cer- 
tain measurements of the physical properties of these 
gases. With regard to argon, he might say that the gas 
Ee nsed was prepared from air, at the Royal Institution 
in London, by what he might call the oxygen method — 
that was to say, the nitrogen of the ordinary air was re- 
moved by the aid of oxygen and with a series of eledric 
sparks. As the proportion of argon in the air, however, 
was so small — only i per cent — the process of separation 
was extremely slow anJd tedious. By means of an eledric 
arc, kept up for several weeks in a mixture of oxygen 
and atmospheric nitrogen, he finally obtained more than 
3 litres of argon at atmospheric i>ressure. Having done 
this, bis primary objeft was to weigh the gas on the same 
acale that othor gases had been previously weighed, in 
order to see whether the gas prepared by the oxygen 
method had the same density as gas prepared by the magne- 
stom method. He might say at once that the density proved 
to be exadly the same. The other physical properties that 
remained available for measurement were the refraAive 
index and the viscositv. The refradive index was mea- 
sured by the interference method. The eyepiece 
was construaed of cvlindrical lenses. To avoid 
the use of cross-wires, the tubes containing the gases 
under comparison were arranged so as not to occupy 
the whole field of view, some light passing parallel to 
ajnd outside them; two sets of fringes were thus 
obtained, which could be brought to coincidence by 
varying the pressure of either gas. Adjustments were 
nuide for several pressures, one of the tubes always con- 
taining air. The refradive index of argon proved to 
be 0*961, only about 4 per cent less than that of air. 

The next question arose as to the corresponding pro- 
pertv of helium. For this purpose he used gas which 
Pfofesor Ramsay had separated from d^veite, and he 
was astonished to find that the refradive index of this 
gas was as low as 0*146. Dry air was in both instances 
taken as the standard, so that the refradion of helium 
was about one-seventh part only of that of the air. It 
might be that at the present time a precisely accurate 
value of the physical properties of these gases was not of 
much consequence ; but if it should be proved, as was 
probably the case, that either or both of these gases were 
mixtures, then a precise knowledge of these properties 
would be of the utmost importance. The refradion of 
helium was far below that of any known gas. 

The other property that he took up was the visco- 
sity of these gases. By viscosity one meant the force 
that was called into play when one layer of gas tended 
to slide upon another ; in pradice viscosity was 
usually measured by the rate at which the gas or the 
liquid could be caused to flow through a very fine capil- 
lary tube* There were some difficulties attending this 
experiment, which he explained, but the results were not 
very importantly affeded. To put the matter shortly, and 
again taking dry air as the standard, be found that the 

* Fov>portioot of thit Report we are Indebted to the East Anglian 
Timu, VtotifM have been sent to each epeaker for corredioo. 



viscosity of argon was z*ai, and of helium 0*96. These 
figures, though less striking than those referring to the re. 
fradive index, threw some light nevertheless upon the 
charader of the gases. If thev compared oxygen and 
air, they would find that the ratio was I'li, oxygen being 
the most viscous gas previously known ; bnt the figures 
he had just given showed that argon was more viscous 
than oxygen, and therefore stood at the head of the list of 
viscous gases. He hoped that some other members pre- 
sent would point out the chemical conclusions that were 
to be drawn from these fads. 

There was one other point that he should like to men* 
tion. Some time last year — in fad almost immediately 
after Professor Ramsay and himself had established the 
existence of argon— they obtained, with the assisUnce 
of Dr. Arthur Richardson, some gas from the Bath 
spring which had hitherto been supposed to be nitro* 
gen. At that time he thought that this gas might prove to 
be in large degree composed of argon. That anticipation 
was not verified. When the Bath gas was treated in the 
same way that atmospheric air was treated, in order to 
isolate what was supposed to be pure nitrogen, it was 
found that the weight of nitrogen so obtained was not 
so great as the weight of nitrogen obtained from the 
atmosphere. The conclusion wM that the Bath gu con* 
tained less argon than might have been expeded ; and this 
rather puzzled him, because argon was more soluble in 
water than nitrogen. The matter rested for a while, un- 
til, in the course of the spring, Dr. Ramsay isolated 
heUum, and found that its density was exceedingly low- 
only about double that of hydrogen. So far as was yet 
known, the chemical properties, or want of chemical 
properties, of argon and helium were about the same, so 
that any process by which ar^on was separated, either 
from air or from the gas of mmeral springs, would also 
separate helium. It was then suggested that the fad 
which had puzzled them with regard to the Bath gas was 
explained by the presence of helium, which had obscured 
by its abnormal lightness the extra density of argon; 
and he had since ascertained by spedrum analysis that, 
as a matter of fad, the Bath gas did contain helium. 
(Applause.) 

Dr. J. H. Gladstone, F.R.S., who was received with 
applause, next read a paper on " Specific Refraction and 
the Periodic Law, with reference to Argon and othet BU^ 
ments." In doing so, he said that in 1869, 1877, and 
1883, he had shown that the specific refradive energy 
of the metallic elements was usually in the inverse 
order of their combining proportions, and that the specific 
refradive energies of the elements in genentl were to a 
certain extent a periodic fundion of their atomic weights. 
The present communication referred to some develop* 
ments of these old observations. With regard to (1) argon, 
the specific refradive energy of argon gas, as reckoned 
from Lord Rayleigh's data, u 0*158. Deeley suggested 
that this might throw light upon the question whether the 
atomic weight is 19*94 or double. If the atomic weight 
be X9*94 the molecular refradion will be 3*15. This figure 
is almost identical with that belonging to oxygen and 
nitrogen gas. Taking the specific refradive energy of the 
elements with atomic weighu between 12 and 23, includ- 
ing argon, as ao; viz., carbon 0*417, nitrogen 0*336, oxy- 
gen 0*194, fluorine 0*03, argon 0*158. sodium 0*209 ; argon 
appears in place on the rise after the great descent from 
carbon to fiuorine. On the other hand, it would seem to be 
out o( place in the neighbourhood of calcium, which has 
a molecular refradion of xo'o, and a specific refradive 
energy of 0*248. (2) The fad that the specific refradive 
energies of the univalent metals are generally inversely 
as the square root of their atomic weights is confirmed by 
further research, the produd of the two being about x-3. 
The same was shown to hold good of the earthy 
metals in the second column of Mendeldeff*s table, the 
produds in that case being fully 1*4. The role does not 
apply to the halogens in colunm VII. As to column Vlll., 
iron, palladium, platinum, and gold all give produds 



234 



DiscussioH OH Argon and Helium. 



iCBElflCAl* NsWt, 

I Nov. 8, 1895. 



which are far higher. This confirms the belief that gold 
18 not rightly placed in colamo I. (3) It is known that 
the refraaion of a salt when dissolved in water is often 
slightly modified by the proportional amount of the 
solvent. The author said that he and Mr. Hibbert had 
recently found that salts of the metallic elements, in 
^columns I. und II. of Mendel^efiTs table, showed generally 
an increased refraAion on dilution, those of metals in 
column VIII. a diminished refradion. 
' Professor Schustbr, F.R.S., then opened a discussion 
•* On ih$ Evidtnct to bt gathsnd as to the simple or com- 
'hound character of a Qas from the Constitution of its 
'Spectrum:* The purpose they had in introducing this 
'subjeft, he said, was to inquire whether they could, from 
the spedrum of a body, draw any conclusions as to the 
pri^bable nature of the gas, as to whether it was compound 
'or simple, or as to the group of chemical elements to 
which it belonged. It might appear at first sight that 
'spedroscopists ought by this time to be able to draw some 
defiiiite conclusions upon these points ; but, in order to 
show the very great difficulties with which they had to 
contend, he woiUd draw attention to the analogous case— 
taking the vibrations of sound instead of those of light. 
If an organ pipe were examined it would be a pretty easy 
'thing to calculate and to learn what different tones that 
pipe would emit. Supposing, however, that thcv were 
outside a room in which bells were placed, possibly half- 
a-doxen, and that they were asked, simplv from the sound 
of those bells, to conclude how many bells there were, 
and what was their shape, and the constituents used in 
making them, then they would be face to face with a 
problem exceedingly difficult, if not incapable, of solution. 
It was a difficulty of this kind in which they were placed 
in regard to the spedrum. He would not go so far 
as to say that every element behaved differently; but 
they certainly did not always behave exadly alike, and 
any conclusions that might at present be drawn from the 
spedrum of a body must therefore be exceedingly uncer- 
tain. Dealing at considerable length with somewhat 
•abstruse fads and theories, the first points presented for 
consideration were these :— What is it that vibrates in a 
body which sends out rays and vibrations of light, and how 
is it possible that bodies which are called monatomic— 
like mercury vapour, for instance— could show not only 
a simple vibration of a definite period, but a great 
multiplicity of lines and a very complicated spedrum ? 
The learned Professor considered that discussion was not 
likely to be produdive of much useful result, simply be- 
cause they had at present so little knowledge of the fads. 
His conclusions were that they required in the first place 
«n accurate mapping of the spedra of compound bodies, 
Und some kind of mathematical theory as to the very 
curious distribution of the wave lengths of both the bands 
and the lines revealed by the spedrum. 

The despondent view of Prof. Schuster was not shared 
by Prof. RuMOS, of Hanover, who at this point contributed 
an account of the researches of himself and Prof. Paschen 
on the spedrum of cl^veite gas— undoubtedly the most 
complete tmalysis of spedra hitherto made— proving that 
helium is not a simple element, but consists of two, and 
not more than two elements. They had proved that the 
spedrum of cleveite gas consists of two systems, each 
with three series of lines, six in all ; the two systems 
can be distinguished by the fad that one of them con- 
sists of double, the other of single, lines. Prof. Runge 
described the method of diffusion by which he and Prof. 
Paschen have altered the relative intensities of the lines 
in these two systems. They find that the double*line sub- 
stance, which gives the line D3, and ought therefore alone 
to be called heHum, is always present in the sun's chromo- 
sphere, and diffuses more slowly than the single-line 
substance. The lattter substance only occurs in spedra 
of the snn*s chromosphere about once in four observa- 
tions. As he resumed his seat, the young Professor, 
whose work in this department is well known to those 
most ileeply interested, was loudly cheered. 



Lord Ravleiqh said the audience had already shown 
their appreciation of the remarkable results ihat Professor 
Runge had put before them with such great lucidity, 
speaking almost as freely as though he had been speak- 
ing in his native tongue. (Applause). There could be 
no doubt that these results were of the highest order of 
interest. He was not himself an expert in spedroscopic 
matters ; those who were would tell them that there was 
little work which could be compared in precision and 
value with that which had now been put before the meet- 
ing. The strong evidence given them as to the compound 
charader of the gas from cleveite was a point of the 
utmost interest. He (Lord Rayleigh) had supposed that 
the probabilities were not against such a conclusion. The 
gas was almost of unknown origin ; the chemical charader 
of it was unknown, and the manner in which it was held 
in the mineral was still entirely a matter of speculation. 
Its division into two elements, and the fad that there 
were no indications of more than two, seemed to be a 
point very well made out, so far as one could exped in 
matters of this kind. He did not know whether Professor 
Runge could tell them anything of the same sort about 
argon— whether he had any presumptions from the spedra 
as to the charader of the element or elements it might 
contain. Without going further, he would leave the con- 
sideration of the matter in more competent hands. 

Dr. G. Johnstons Stonby, F.R.S., said that his ad- 
miration of the splendid piece of work which had been 
carried on by Prof. Runge and his colleague, dated from 
the original publication of the results of their invest^a- 
tion some six weeks ago. Then he was so deeply im- 
pressed with its importance, in the present position of the 
investigations with reference to these elements, that be at 
once wrote to the editors of the Philosophical Magazine, 
and they had inserted a translation (PAi/.ifn^., Sept., 
1895) of the principal memoir for the better information 
of residents on this side of the German Ocean. Dr. Stoney 
was just touching upon the paper he had to read, when 
Prof. Lodge made a private communication to him. 
Turning aside for the moment. Dr. Stoney said it would 
be very advisable at that Jundure to call attention to the 
unfortunate position in which scientific investigation in the 
British Islands stood in comparison with that of at least 
one other country in Europe. These was no scientific 
man in these Islands who possessed a laboratonr 
furnished with the appliances for carrying on such 
investigations as those which had just been placed 
before the meeting. Their knowledge of the subjed was 
therefore in a somewhat correspondingly backward posi- 
tion. This was a difficulty for which a remedy should, 
he thought, be found as soon as possible. An apparatus 
which would measure the half or the third of a tenth 
metre would really do nothing in an investigation of this 
kind ; they must procure apparatus, like the splendid ap- 
paratus in Hanover, which would measure to the fiftieth 
part of a tenth metre with certainty. 

Dr. Armstrong (intervening) said he should like, on be- 
half of the chemists, who had not said anything up to that 
time, to express the universal admiration which they must 
all have of the communications just made to the meeting. 
He had risen at that jundure not merely with the objed 
of saying this, but also in order to corred the impression 
which Dr. Johnstone Stoney had just endeavoured to 
make, at the instigation of Professor Lod^e, that tbey 
were not capable of doing this kind of work m the British 
Isles. 

Professor Lodge— It was not my instigation. I was 
just reminding Dr. Stoney of something that I knew, from 
what he said to me last night, he was anxious not to for- 
get to say. (Laughter). 

Dr. Armstrong— And that happens to agree rather 
curiously with your particular views. (Renewed laughter). 
The Dodor went on to say that this work had been done 
in Hanover by individual effort, after the fashion usual in 
England. If the idea of making such investigations as 
these oocurred to men in this country, who had the 



CHUIICAL If BW8, I 

Not. 8t 1895. I 



Discussion on Argon and Helium. 



225 



requisite capacity for undertaking them, he was sure 
that the effort would always be made. 

Dr. Johnstone Stoney then read his paper on •• Tkt 
Interpr$tat%on of Linear Spectra," The abslrad of his 
argument was as follows : — 

In most of the spe^ra that consist of lines, very re- 
markable groups present themselves, in which the lines 
are seen to be associated into definite series. In such 
cases, except under special circumstances, we may safely 
presume that all the lines of a group arise from the motion 
of a single elt^ron in each molecule of the gas. Very 
striking examples of such groups are present in the 
absorption-spedrum of oxygen and in the bright line 
BpeArum of carbon. The oxygen of the earth*s atmo- 
sphere produces the great A group of double lines in the 
solar spedrum, as well as the very similar great B group, 
aind the a group. It also produces a group more refrangible 
than D, about which we know less. This group is much 
fainter than the others, and it is only under exceptional 
circumstances that it can be seen at all in the solar spec- 
trum. Each of the other three groups can be distinguished 
into two sub-groups ; which from their appearance have 
been called a head and a train. The general features of 
these three groups are the same, and Mr. Higgs has made 
a careful geometrical analysis of one of them, the great 
B group {Proceedings of the Royal Society, March, 1893, 
p. 200). From his analysis we may infer that the head 
and the train are due to motions in the molecules which 
are distind, although related to one another. This con- 
clusion receives further support from the circumstance, 
that in the double lines of " the head,** it is the violet com- 
ponent of each pair which is the stronger; while in the train 
It is the red component of each pair which is the stronger. 
In a paper in the Scientific Transactions oj the Royal 
Dublin Society for xSgx, p. 563, the present author pointed 
out that if we proceed on the probable supposition that 
the motion of each eledron is an orbit of some kind going 
on within the molecules, it can be shown that the partials 
of the motion of the eledron which causes the lines are 
elliptic partials, and that where an elliptic partial suffers 
an apsidal perturbation, it divides into two circular sub- 

Sartials, giving rise to the two constituents of a double 
ne^ We may infer from this that the sub-partials cor- 
responding to the red constituents of the fourteen or more 
double lines of the train of B are circular motions revolv- 
ing one way, and that all the violet constituents of these 
double lines result from circular motions revolving the 
other way. In order to advance beyond this point, it is 
necessary to make two further hypotheses which probably 
are both true. Two hypotheses must here be ventured 
upon, because observations with the speAroscope give us 
no information as to the phases of the elliptic partials or 
the planes in which they lie. One hypothesis that recom- 
mends itself is that the circular sub-partials belonging to 
a conneded series of double lines, e.g., to the train of the 
great B group, lie in one plane. Another hypothesis 
which we may venture to make, as a preliminary working 
hypothesis, is that the amplitude of the motion of the 
^fedron has its maximum value at starting, i.e., when 
that event has occurred at the close of a struggle between 
two molecules which has set up that motion of the eledron 
which continues during the comparative repose of the 
quiet, undisturbed journey in which the molecule is in- 
dulged after its encounter. With these assumptions it is 
possible to synthesise all the motions causing the red con- 
stituents of the double lines into one motion, which is, 
however, not circular, but a slowly contradiog spiral ; 
and a similar resultant spiral motion turning the opposite 
way is furnished by the sub-partials forming the violet 
constituents. While these spirals are being traversed, the 
radii or semi-amplitudes of the circular motions of which 
they are composed, and which correspond to the individual 
lines in the spedrum, are becoming shorter or longer, 
owing to the escape of energy to the ether or absorption 
of energy from it ; so that the adual orbits are spirals 
lying somewhat inside or somewhat outside those which 



result from the assumption that the radii retain their 
length. These two spiral motions combine at each 
instant into a single elliptic motion so elongated that it 
is nearly a linear vibration, and this elliptic motion con- 
tinues to represent what occurs, if subjeded to the five 
following perturbations :~ 

X. A decrease of amplitude. 

a. A diminution of periodic time. 

3. A slow apsidal motion in a diredion opposite to that 
in which the revolution of the eledron in the orbit takes 
place. 

4. A slight fluttering motion which may be represented 
by a very shallow wave running rapidly round the ellipse. 

5. A further slight modification of the form of the 
ellipse which takes the form of a secular perturbation. 

Accordingly we arrive at the conclusion that an elli|>tic 
motion undergoing these perturbations is such a motion 
of an eledron as would produce the entire series of lioet 
in the train of B. A similar motion would produce the 
train of A, of a, and of each of the other similar groups* 
if such exist in the spedrum of oxygen. These elliptic 
motions undergoing perturbations may be appropriately 
called mega-partials in their relation to the adual orbit 
described in oxygen by the eledron that produces all these 
trains of lines, since that orbit is the resultant which we 
should get by superposing the motions in these few mega- 
partials. A similar treatment applied to *' the head '.' of 
any of the oxygen groups shows that it, too, arises from 
an elliptic motion subjed to perturbations, the chief dif* 
ferences being in the law conneding the falling-off of 
amplitude and the periodic time, and that the quick 
fluttering perturbation is absent; also that the apsidal 
motion takes place in the opposite diredion. In oxygeo« 
the strength of the lines of each sub-|roup fades out to- 
wards the red. When the fading is in this diredion, it 
can be shown that the periodic time decreases as the 
amplitude falls off. Where, as in the carbon groups, the 
lines fade out towards the violet, the periodic time be- 
comes longer as the amplitude decresses. And, finally, 
if the lines present themselves, when plotted on a map of 
oscillation frequencies, as disposed symmetrically on 
either side of a common centre, this indicates that the 
periodic time continues unchanged during the shortening 
of the amplitude. This suggests the cause of the width 
of spedral lines in general, so far as their width is not 
merely apparent, f.#., due to the Doppler effed of the 
translational motions of the molecules, or to the breadth 
of the slit of the spedroscope. The rest of the width of 
the line, as seen, is its true physical width, and seemf 
to be due to the interchanse of energy between the mole- 
cule and the ether. This leads to diminished amplitude ; 
.and this redudion of the amplitude may be accompanied 
by either a redudion, or an increase, or a persistence un- 
altered of the periodic time; according to the way in 
which the motion of the eledron is dynamically 
associsted with the rest of the events which go on within 
the molecule. If the periodic time decreases, this giveft 
rise to a ruling fading out towards the red ; if there be 
an increase of the periodic time, the shading is towards 
the violet; while if the line fades out both ways sym- 
metrically, there is no change in the periodic time. The 
relative intensities and the spacings of the lines of the 
ruling depends on the law which conneds the escape of 
energy, and the shortening of the semi-amplitude ; and in 
its turn this law depends on the dynamical relations in 
which the parts of the molecule stand to one another. 
The excessively fine rulings of which the widths of indi* 
vidual lines consist, can probably not be seen otherwise 
than as a shading, unless perhafjs in soine verv few ex- 
ceptional instances, owing to their being blurred together 
by the Doppler effed. We have attributed these very fine 
rulings to the interchange of energy with the ether. On 
the other hand, the more conspicuous rulings, stich aa 
those we have been studying in oxygen and carbon, seem 
to be associated with the transference of energy from one 
motion within the molecule to another. This may be 



226 



Chemical Researches and Spectroscopic Studies. 



i CBlMf CAL KbWS, 

I Nov.'B, 1895. 



briefly described by saying that the widths of the indi- 
vidual lines and their being in various ways shaded off, 
are doe to radiation, while that they are arranged in series 
is dne to conduaion. 

A Discussion followed (the audience having by this time 
become very thin), the speakers includine Professor 
Liveing, Lord Kelvin, Professor Fitxgerald, and Dr. 
Macfanane Gray. Two or three papers on "Ortho- 
chromatic Photographv '* were held over to a later meet- 
ing, probably in the Chemistry Sedion. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By JEAN SBRVAIS STAS. 

(Cootinned from p. 216). 

On ihi Coof-Gox.— When the air is pure, coal-gas taken 
direa from the main burns in a Bunsen burner, or blow- 
pipe, or blowpipe fed with air or oxygen, without showing 
a trace of the sodium line on spedroscopic examination. 
During my examination of the coal-gas spedrum, I tried 
whether the presence of compounds of ammonia or cyan- 
ogen modified it. With this view I examined the spec- 
trum of oxy-coal-gas, made with gas either taken dired 
from the main or kept in a gasometer where it was 
stored, having been previously deprived of compounds of 
ammonia and cyanogen by its passage through flasks 
filled with broken pumice-stone, and moistened resped- 
ively with a strong solution of caustic potash and sul- 
phuric acid diluted with its volume of water. I have 
never deteded any difference between the spedrum shown 
by ordinary gas and that by the gas purified as above. 

With the objea of economising oxyhydrogen-gas as 
much as possible, on account of the difficulty of preparing 
hydrogen fulfilling all requirements, I often used oxy- 
coal-gas to eliminate, from compounds, the sodium which 
is accidentally contained in them. I also used the oxy- 
coal-gas blowpipe, which is very much easier to manipu- 
late, to check the results given by the oxyhydrogen burner. 
These requirements led me to examine the oxy-coal gas jet 
formed from coal-gas under pressures respeAively of four 
and fivi cm. of water. The results having been the 
same, I shall limit myself to mentioning here those ob- 
tained under constant pressure otfour cm. of water. 

When iki internal surfaces of the service-^ipe and burner 
were thoroughly moistened, the gaf-jet issuing from a 

{>latinum burner, with a hole z m.m. diameter, formed a 
ominous flame 35 cm. high and i\ cm. diameter. 
When the supply of oxygen was regulated so that all lu» 
minosity disappeared from the flame, its height was 
reduced to 17 cm. and its diameter to 7 or 8 m.m. 

In pure air this flame is deep pure blue, without an 
inner cone ; speamm analysis of it shows an absolutely 
dark spedrum. On gradually increasing the supply of 
oxygen, the colour intensity of the flame decreases and the 
light intensity increases ; instead of deep blue it becomes 
sky'blue. It develops at the same time a highly lumi- 
nous inner cone, pure light blue in the absence of sodium, 
and pale blue tinged with green whenever it has the least 
trace of sodium in it. Spedrum analysis of the sky.blue 
flame and of the inner cone reveals a hydrocarbon spec- 
trum. I found that the luminous intensity was greatest 
and the spectrum most complete when the inner cone was 
reduced from its original height of 9 or zo cm. to about 
^ cm. Whatever the height of the inner cone might be, 
the appearance of its spedrum is the same ; it consists 
of six well-marked bands, shaded from left to right : one 
reddish-brown band, two bands of different shades of 
green, and three pure blue bands. The bands are defined 
by lines, the number of which varies with the luminous 
intensity of the cone. With maximum intensity, ex- 
amining the apex or one side of the cone, the bands are 
nade up as follows : — 



z. The red band— composed of four sharp very bright 
lines, situated between 43 and 49*00 the micrometer 
of my Steinheil speAroscope. Farther on I shall 
give its value as a fundion of FraCinhofer*s " A, B, 
C, D, E,6, F, G. H'Mines.* 

2. The first green band—composed of four sharp very 

bright lines, situated between 56 and 66 on the 
same micrometer. 

3. The second green band — composed of three very 

bright lines, situated between 72 and 77 on the 
same micrometer. 

4. The first blue band — composed of five sharp nnes« 

less bright, situated between 90 and 96 on the mi- 
crometer. 

5. The second blue band — composed of four faint lines, 

situated between Z13 and 115 on the micrometer. 

6. The third blue band — nebulous and very faint, extend- 

ing from Z17 to 1x8 on the micrometer. 

When the luminous intensity was not at its maximum, 
but yet the bands were broken up into quite distinA lines, 
the second green band consisted of only two lines and the 
first blue band of only four lines, instead of three and five 
lines respedively. 

The coal-gas spedrum generally recognised appears 
then to be an incomplete spedrum. The connedion be- 
tween the number of lines in the coal-gas S{>edrum and 
its luminous intensity is undoubted, and the influence of 
a rise of temperature on them both seems to me in- 
disputable. 

I made a set of experiments to ascertain what influence 
the lines in the coal-pas spedrum had on the spedra I 
was studying under different conditions, and I found out 
definitely that the spedrum of sodium, potassium, thal- 
lium, lithium, calcium, strontium, and barium is thi sam$ 
when rendered incandescent either in an oxyhydrogen or 
oxy»coal'gas blowpipe. Having obtained the coal-gas spec- 
trum, it suffices to place a compound of sodium, potassium, 
thallium, lithium, calcium, strontium, or barium in the de- 
sired part of the jet, in order to extinguish completely all 
lines in the coal-gas spedrum, and replace its charaderistic 
bands and lines by the lines of each of these metals, f 
Doubt is only possible in the case of the green lines shown 
at a very high temperature by barium compounds. This 
metal itself has a band made of very fine green lines, as 
observed by M. Bunsen, that might be mistaken for the 
green lines in the coal-gas spedrum. I shall be more 



* I refrain from giving the exadt position of each band and Ihia in 
the coal-gas ape^rum. because in many cases the limit of error 
in assigDUig the position is greater than the distance between two 
adjacent lines. 

t I call the appearance of the coal-gas spedmm the titxbUUy oi 
the charaderiitic lines and banda seen during spe<ftnim analysfs of 
the hiner cone of an oxy-coal-gas blowpipe, and in the same way I 
designate by the term extinction the non^vUihili^ of lines of bands 
previously seen. I hold that a apedtrum formed of lines and bands 
can exist in the background of the speAmm without being visible to 
the sharpest eye. Thus, when one makes, by means of a speAro- 
scope of low abiorption power, and fitted with a micrometer wiUi a 
luminous scale, a spedlroscopic examination of a short indndibn 
apark without a condenser, between two platinum pointa, in air /ivs 
from sodium^ and when one refrains from illuminating the spe&rum, 
one always sees a spectrum of atmospheric lines and bands on ma 
absolutely dark background. By then illuminating the speAram, 
whether by coal-j^as or by the radiation from an incandescent plati- 
num ball, one instantly masks the spcArum of the atmospheric 
bands ana linea ; the eye ceases to see them. The banda and linea 
are in this case replaced by a continuous spectrum, the intensity of 
which is in proportion, at the same time, to the intensity of the spec- 
trum of the atmospheric lines and to the intensity of the source of 
light. The observer can at pleasure, and without limit aa to the 
number of repetitions, cause to appear or disappear the two kinds of 
phenomena. During the revision of my speAroscopic studies with 
Prof. Depaire, we frequently had occasion to verify the perfeA troth 
of the fafts stated above, and we convinced ourselves that it was not 
possible to obtain by spectrum analysis, even of a short induAion 
spark without a condenser^ a speArum free from atmospheric lines 
and bands, when we reframed from lighting the micrometer with a 
laminooB scale. The light from the micrometer, whilst extinguishing 
the speArumof the atmospheric lines, always replaced it either by 
diffused light or by a more or less well-defined continuous apedtrom. 
In my opinion it is proved to be impossible to obtain a spark spectrum 
mithout atmospheric lines and bands when the background is darjc. 



f Mov. 6, 1895. I 



Estimation of Simple Cyanides. 



227 



expltctt ott this point when I describe the results of my 
stodtet on these last compounds. 

Tho ravs from the metallic compounds I have just 
meatioaed extinguish—that is, render invisible— the rays 
from coal-gas burning in oxygen. The vapours of thallium 
mad sodium, especially thallium, extinguish the lines of 
coal-gas most easily, but one must raise the vapour of 
barium compounds to the highest possible temperature 
bclofft it will make a coal-gas speArum completely dis- 

Besides this, one finds in some of these bodies this 
pfo p ci ty of extisguishing others. Thus the thallium 
flame extinguishes barium rays even to the point of 
nsasking the spedrum of a spark through barium. I shall 
feluni to this subj«ft when describing my studies on the 
tkalUam speArum. 

Experience has taught me that, whilst conforming to 
the conditions mentioned above, I can use indiffierently — 
M I have done— an oxy hydrogen or oxy.coal-gas blow- 
pipe* In every case I checked my observations the one 
tj the other. 

Spedrom analysis of the ele^ric arc passing between 
pmn carbon eledrodes, and charged with a compound of 
one of the metals mentioned above, led to results differing 
from those yielded by spedrum analysis of the oxy-coal- 
gas t>lowpipe charged with a compound of the same 
metals. 

However Intense the current producing the arc might 
be, the charging of it by the metallic compounds men- 
tioned did not extinguish the eleAric carbon lines when 
they appeared. The speArum seen showed at the same 
time, with pitftci cUamess, the charaAeristic carbon lines 
and bands, and the charaderistic lines and bands of the 
metallic compound pat into the arc. This spedrum showed 
the lines and bands of both spedra superposed. 

When using carbon eledrodes for forming the arc I had 
•ome work to do to pick out the lines belonging to the 
carbon spedrum and those belonging to the spedrum of 
the body put into the arc. I did this sorting with an arc 
charged with a compound of each of the metals. 

In order to be able to make the seleAion, I first studied 
the spedrum of carbon in the arc, employing the spedro- 
scope I had used to examine the inmr com of an oxy- 
coal-gas blowpipe flame brought to its gnatest luminous 
intensity ; I have given above the results of this latter 
examination. 

When carrying on this delicate work I found, |ust as 
II. Fievex has done,* that the numbtr and fosiiion of the 
lines and bands in an eledric spedrum of carbon were 
identical with the numbir and position of the lines and 
bands in the flame spedrum of oxy-coal-gas. 

I found this identity with an arc varying from 4 to 25 
m^oi* in leitfth, both with the spedroscope I originally 
need and with different spedroscopes, as I shall mention 
later on. 

When superposing a coal-gas spedrum on an eledric 
spednm of carbon, and showing, by this means, the 
identity of the number and position of the lines and 
bands in the two spedra, I found that the lines and bands 
in an eledric spedrum of carbon invariably stood out on 
a caniinmout spedrum. This continuous spectrum was 
9mtif€lf wantinf in the appearance of a coal-gas spectrum, 
whichever spedroscope might be used. 

On account of the presence of a continuous spedrum, 
more or leu intense, according to the luminous intensity 
of the arc passing between carbon eledrodes, when 
pottiiig into the arc a compound of which one wishes to 
form an eledric spedrum, I have always placed the 
spedroscope at a suitable distance for diminishing, as far 
aa possible, its intensity, whilst leaving to the lines and 
bands of the metallic compound sufficient luminosity to 
permit the identification of the eledric carbon lines and 
bands, which retain sufficient luminosity, varying with 

• **Ncw RetMfcb«t 00 tbt Carbon Spearatn/* by Cb. Ficvcs 
OotmuU of the Royal AMdtmy of Bitgium, 3rd Series, vol. ziv , p. 
100). 



the distance, to allow of a perfedly accwra f identi* 
fication. 

One knows, besides, that when nsln^ a strong ihomgk 
short spark, or an eledric discharge m air or nydrogeo 
charged with a metallic compound, it is equally necessarjr 
to sort out in the spedrum seen the lines doe to the me- 
tallic compound, the atmospheric lines and bands, and 
the hydrogen lines, which are produced at the same time. 
In my opinion the identification of the carbon bands and 
lines m the spedrum of an arc made by a cnrrttti though 
very trving to the eye, is easier, on account of the clear- 
ness of the lines, than that of the atmospheric bands aad 
lines of the spark and eledric discharge, which, howeiw 
one makes it, always remain more or less diffused, very 
often masking the sharp definition of lines of the metallic 
compounds in their neiehbourhood. 

Notwithstanding all these difficulties, I used, as a wuthod 
of chechifig, all these different means of producing an 
Sedric spedrum of the bodies on which I was carrying 
on my investigations. 

(To be oontioQsd). 



ON TRB 

ESTIMATION OF SIMPLE CYANIDES 

IN PRESENCE OF COMPOUND CYANIDES AND 

CERTAIN OTHER SUBSTANCES. 

Bjr J. E. CLBNNBLL, B.Sc.. 

Cbief Cbenitt, Raod Central Ore Redaction Co., 

Johannetbarg, Sovtb Africa. 

Thb presence of other cyanogen compounds mav interfere 
very seriously with the corred estimation of the simple 
alkaline cyanide in a given solution. In the treatment 
of ores by cyanide, various compounds, snch as lerfo* 
cyanides, sulphocyanides, &c., may be formed. 

It is desirable to know the extent to which the presence 
of such bodies interfere with the estimation of the simple 
cyanide. A determination of the double cyanides them- 
selves is also useful at times, since it may enable as to 
judge of the nature and extent of the decomposition of 
cyanide occurring during the leaching process, and to 
suggest a suitable means of diminishing this decomposi- 
tion. It is also sometimes desirable to determine the 
quantity of the various cyanogen compounds in the solo* 
tions leaving the " precipitation-boxes,*' in order to ascer* 
tain the nature of the losses occurring in precipitation, 
and to decide what means may be adopted for recovering 
the cyanogen from the compound cyanides contained in 
these liquors. 

I. 

The following experiments were therefore made to 
determine the mfluence of various subsunces liable to 
occur in pradice on the estimation of the simple cyanide. 

K.^Influence of Ferrocyamidis, 
The presence of ferrocyanides interferes with the cor* 
red estimation of the cyanide by means of silver nitrate* 
causing the indications to be somewhat too high. The 
error is of importance, however, only when the percent- 
age of cyanide is relatively small. The efled 01 varying 
quantities of ferrocyanide of potassium on the estimation 
of potassium cyanide is shown below. The standard ferro- 
cyanide solution contained 0*5 per cent K4FeCys.3HsO. 

Potaatlon Poiaatinm Standard SttwuRb 

No. of cyanide, ferrocjrftnide, AgNO. ofKCy Psfosntags 

test. 0*1 per cent. 0*5 per cent, reqoired. indicated, of error. 
O.c. C.c. 



I. 

t. 
3. 
4. 
5. 



25 
25 

25 
25 
25 



5 

10 

«5 
ao 



"81- 
25 

a-6 
2t5 

29 



Per cent. 
O'X 

o'X04 
0*11 
o*xi6 
0*1 16 



+4 
+10 
-I- 16 
+ 16 



228 



Estimation of Simple Cyanides. 



t Cbbmical Nbvs, 
\ Kov. 8, i8g5. 



The error introduced by the presence of ferrocyanide is 
less when the ** iodine '' method of titration is used, as 
shown by the following experiments :— 



Potauiom 
No. ot cyanide, 
test. 0*0954 per 

cent. 

0.C 

1. 25 

2. 25 

3- 25 

4- as 

5- as 



Potauinm 

ferroqrftnide, 

o'sper 

cent. 

O.c. 



S 

zo 

IS 
20 



Standard 

iodine 
required. 

O.c. 

7*45 
7-50 

7'6o 
7-SS 



Streo£th 

of KC^ Percentage 
indicated, of error. 

Per cent. 
0-0954 
0*0960 
0-0954 
0-0973 
0-0966 



+0-63 

+ 1-99 
+ 1-27 



B.^InfluiHCi of Ferricyanides, 

The presence of ferricyanides interferes very slightly 
with the correA estimation of cyanide either by the silver 
nitrate or by the iodine method. When silver nitrate is 
ns^t a reddish brown precipitate of ferricyanide of silver 
at first appears instead of the white precipitate of cyanide 
of silver, and re-dissolves as long as an excess of cyanide 
is present. 

A decinormal solution of ferricyanide of potassium was 
prepared, containing 32*9 grms. per litre. 

A mixture was made of zo c.c. 0*905 per cent potassium 
cyanide and zo c.c. N/io potassium ferricyanide. 

This required 9 c.c. standard silver nitrate, indicating 
0*9 per cent KCy. 

The following tests were made by the iodine method :— 



Potaatiom 


Potaaaiam 


SUndard 


Strength 
.ofKQf^ 




No. of cyanide. 


ferricyaoidc. 


iodine 


Percentage 


teat. 0-0947 per 


3*a9Per 


required. 


indicated. 


of error. 


cent. 


cent. 








O.C. 


C.C. 


C.C 


Per cent^ 




Z. 25 


— 


7-40 


00947 


— 


2. 25 


S 


73S 


0-094Z 


-0-63 


3. a5 


zo 


7*3S 


0094Z 


-0-63 


4- a5 


IS 


730 


0-0934 


-1-37 


S. a5 


20 


7-25 


00928 


-2 



The amount of cyanide may be estimated with toler- 
able accuracy by the iodine method in presence of both 
ferro- and ferricyanide in the same solution. 

A mixture was made of 25 c.c. 0-5 per cent ferrocyanide, 
zo C.C. 3*29 per cent ferricyanide, and 25 c.c. 0*098 
per cent cyanide. 

This required 7-3 c.c. standard iodine, indicating o-z 
per cent potassium cyanide, the end-point being quite 
sharp. The same mixture, tested by silver nitrate, re- 
quired 3-z c.c. indicating o*z24 per cent KCy, the end- 
point being rather indefinite. 

C.-^Influenci of Suiphocyanidis. 
Sulpbocyanide (thiocyanate) of ammonium interferes 
with the estimaticn by silver nitrate, rendering the end- 
point somewhat obscure. It does not appear to interfere 
with the iodine method. 

An approximately decinormal solution of ammonium 
sulpbocyanide was prepared, 
(a) 25 c.c. 0-092 per cent KCy and zo c.c. standard 
sulphocyanide required 23 c.c. AgNOs, indicating 
0-092 per cent KC;y. 
(6) 25 c.c. 0*092 per cent KCy and 25 c.c. standard 
sulphocyanide required 2*05 c.c. AgNOj, indicating 
0*082 per cent KCy. 
(c) zo c.c. 0-092 per cent KCy and zo c.c. standard 
sulphocyanide required 2-75 c.c. standard iodine, 
indicating 0*092 per cent KCy. (z c.c. iodines 
0-00334 grs. KCy). 

D. — Influtnci of Ammonium Carbonate, 

It has been pointed out by J. S. McArthur that the 

indications by the silver method are too high in presence 

of ammonium carbonate, and that the error may be redi- 

fied by the addition of potassium iodide, which forms 



iodide of silver, insoluble in ammonium salts. This state- 
ment was verified by the following experiments :— 



KCy Deci- 

No. of (0*094 per normal 
teat. cent). (NH«),COs.Ha0.reqnired. indicated. 



Standard Percentage 
AgNO, of KCy 



RomaikB. 



Z. 
2. 
3- 
4» 

s. 

6. 



O.C. 

as 
as 
as 

as 
as 
as 



C.C. 

zo 
20 
30 
SO 
SO 



C.C. 
2-35 
2-45 
2*55 
2*60 
2-65 
2-40 



0-094 
0-098 

0*Z02 

0-Z04 
o*zo6 
0-096 



Without KI. 



WithKI. 



E,^Influinci of Zinc DouhU Cyanide. 
In the presence of the alkaline double cyanides of xinc 
the indications by both methods are quite indefinite. 
When any appreciable quantity of xinc is present it is 
praAicall^ impossible to obtain a corred readine. When 
no other impurity is present the amount of simple cyaiude 
may be arrived at from an estimation — 

z. Of the " total cyanide," ».e., the equivalent in potato 

sium cyanide of all the cyanogen present ; 
2. Of the zinc, from which the amount of doable 
cyanide {e,g*, KaZnCy4) may be calculated. 

II. 
We have now to consider the estimation of the varions 
compound cyanides, in presence of one another, and of 
the simple cyanides. For pradical purposes no method 
is admissible which is not easily and rapidly executed, 
and which does not give perfe^ly definite and unmistake- 
able indications. Many of the methods commonly de- 
scribed in the text-books are therefore excluded. 

A,^EsHmation 0/ Ftrrocyanidis, 
In the absence of other reducing agents, the estimation 
of ferrocyanides may be carried out by the method off 
De Haeo, which consists in diluting a measured volume 
of the solution, acidifying with sulphuric acid, and titrating 
with potassium permanganate. The presence of cyanides 
and ferricyanides does not interfere seriously with this 
readion, but it is doubtful whether it would vield reliable 
results with the impure solutions from the leaching vats 
and ** zinc- boxes." Probably Erlenmeyer's modificatioii« 
in which the ferrocyanide is first precipitated as Prussian 
blue, would yield better results, but the estimation wookl 
be too tedious for general use. 

A standard permanganate solution was prepared, such 
that— 

z c.c. —0*04 grm. ferrocyanide (KiFeCyC'SHaO). 
The following tests were made :— 

0*5 per cent ferrocyanide taken 
N/zo ferricyanide taken • • • • 
0*9 per cent cyanide taken 
0*095 per cent cyanide taken • • 
Permanganate re(]uired • . • • 
Ferrocyanide indicated • . . . 

B. — Estimation of Ferricyanides* 

The estimation of ferricyanides mav be made by 
Lenssen's method, with Moht's modification. 

The presence of ferrocyanides does not interfere 
seriously. In the presence of cyanides the indications 
were found to be somewhat too low. 

A decinormal solution of potassium ferricyanide was 
prepared. (32*9 grms. per litre). 

The following tests were made (see Table next column). 

CSstimation of Zinc Double Cyanides. 
An approximate idea of the quantity of zinc in the 
solution may be obtained by adding a known excess of 
standard ferrocyanide, and titrating the acidulated solu- 
tion with permanganate, as in De Haen*s method. On 



(fl). 


(fr). 


(c). 


25 c.c. 


50 c.c 


25 cc. 


— 


zo „ 


zo M 


as .. 


— 


— 


— 


— 


zo „ 


3*1 », 


6-2,. 


3'05 » 


0*496^ 


0-496^ 


o-4885t 



/ 



CnsmcAL Miwt, 1 
Mov. 8, 1895- » 



Estimation of Simple Cyanides. 



229 



(a), 
zo 



(ft). 

10 



(c). 
10 



(rf). 

zo 



10 — 



25 



— zo — 



N/ioferricyanide taken, c.c. 
o'5 per cent ferrocyanide 

added, c.c. ~ 

0*9 per cent cyanide 

added c.c. — 

oroQS per cent cyanide 

added c.c. — — — 25 

Potafaium iodide added, gnn. z z z z 

Coac. hydrochloric acid 

added c.c. 222a 

Zinc SQlphate (o*z per cent 

Zn) added (neutralised 

with NaaCOs) .. c.c. zo 20 20 20 

Nmnber o? determinations 

made 3 2 6 z 

Mean N/zo thiosolphate re- 
quired C.C. zo*03 9*68 9*67 zo*o5 

Perricjranide indicated, p.c. 3*28 3*27 3'Z7 3*3 

addition of ferrocyanide to the zinc cyanide solution no 
precipiute is formed at first, but on acidulating the zinc 
It thrown down as an insoluble ferrocyanide which is un- 
afibded by potassium permanganate. The difference be* 
tween the amount of ferrocyanide added and the amount 
foQod therefore indicates the equivalent of the zinc pre- 
•eat. The percentage of zinc found, multiplied by 4, in- 
dicates the percentage of potassium cyanide (KCy) which 
baa entered into combination with zinc to form the double 
cyanide fKaZnCy4). 
The following tests were made :— 

(fl). (6). (c). (d), 
o'9 per cent cyanide taken, 

cc* 25 25 25 25 

Zinc sulphate solution 

added c.c. z 2 3 4 

Containing zinc ..grm. o*oz 0*02 0*03 0*04 
•'5 per cent ferro^anide 

•ohitiott added .. c.c. 25 25 50 50 

Coolaining ferrocyanide, 

grms o'Z25 o*z25 0*25 0*25 

Parmanganate required, c.c. 2*z z 2*85 Z75 
fiquhralent to ferrocyanide. • 0*084 ^'04 o*zz4 0*07 
Panocyanide combined with 

ainc o'04Z 0*085 o'>3^ o*z8o 

Parrocyanide per grm. of 
«uic 41 4'g5 4'5 4 5 

Mean 4*34 grms. 

Taking the atomic weight of zinc as 65, and the mole! 
colar weight of potassium ferrocyanide (K4FeCy6.3HaO' 
at 482, then— 

3Zn : a{K4FeCy6.3HaO) : : z : 4*33. 
The nean of the four tests quoted above showed a pro- 
portion of z : 4*34. 

It therefore appears probable that the following readion 
takes place :— 

3KflZnCy4+aK4FeCy6+ Z2H2S04» 

<-KaZo3(FeCy6)a+i2KHS04+i2HCy. 

D. — Ditirmination of " Total Cyanidt ** in pr$unct 

of Zinc, 
If an excess of potassium ferrocyanide be added to a solu- 
tion containing the zinc double cyanide, and the resulting 
solution be titrated with standard iodine, a few drops of 
dilute starch solution being used as indicator, we may 
determine the equivalent in potassium cyanide of the 
free alkaline cyanides and the zinc double cyanide. The 
cyanogen present as ferro- and farricyanide is, of course, 
not determined. This method or estimating the ** total 
cyanide " is much simpler and more rapid than the 
method by precipitation with sodium sulphide previously 
described (see Chemical Nbws, vol. Ixxi., 274), and ap- 
pears to be equally accurate, provided that other sub- 



stances capable of reading with iodine are absent. Un- 
fortunately, the solutions which pass through the zinc- 
boxes are subjeded to the powerfully reducing adion of 
nascent hydrogen, so that any indications obtained from 
them by the iodine method are of questionable value. 
The presence of alkaline sulphides, sulphites, or thio- 
sulphates would be fatal to the estimation of cyanide by 
this method. 

Solutions containing free hydrocyanic acid must first 
be neutralised by the addition of caustic soda. Solutions 
containing free caustic or monocarbonated alkali must 
first be neutralised by the addition of the necessary quan- 
tity of hydrochloric acid (see Chemical News, vol. Ixxi., 
PP- 93. 274). 

The following equation affords a simple explanation of 
the observed result, though several others are possible :— 

2KaZnCy4-|-K4FeCy6+8l2"Zna(FeCy6)+8KI-|-8ICy. 

In any case the cyanogen of the zinc double cyanide is 
determined as though it existed as free KCy. The zinc 
ferrocyanide comes down as a dense white precipitate 
before the end of the readion, which, however, does not 
interfere with the observation of the end-point. 

With the limitation pointed out above this method 
yields excellent results. 

(a) A mixture was made of zo c.c. 0*093 per cent KCy 
and z C.C. pure ZnS04 (containing o'ooz grm. Zn). 

This required from 2*3 to 2*55 c.c. of standard iodine, 
indicating; 0*074 to 0*082 per cent KCy, the end-point 
being quite indefinite. 

The same mixturet to which 5 c.c. of 0*5 per cent ferro* 
cyanide were added, required 2*9 c.c. of standard iodine, 
the end-rea^ion being perfe^ly sharp, indicating 0*093 
per cent KCy. 

{h) A mixture was made of zo c.c. 0*25 per cent KCy 
and 0*5 C.C. pure ZnS04 (containing 0*005 S^o* 
Zn). 

By dired titration with iodine the indications were quite 
indefinite, from o*zz to o*z5 per cent. After adding zo 
c.c. of 0*5 per cent ferrocyanide and titrating, 7*65 c.c. 
iodine were required, indicating 0*245 per cent KCy. 

(c) A mixture was made of 40 c.c. 0*25 per cent KCy 

and zo c.c. pure ZnS04 (containing o*oz grm. Zn). 

zo c.c. of this liquid should therefore contain 0*02 grm. 
KCy and 0*002 grm. Zn. 

The mixture was shaken up with lime and filtered, 
zo c.c. of the filtrate were mixed with Z'5 c.c. standard 
silver nitrate, which gave a strong turbidity, and titrated 
with N/zo hydrochloric acid, using phenolphthalein as 
indicator. z*9 c.c. of acid were required. Another zo 
c.c. of the filtrate were mixed with z*9 c.c. N/zo hydro- 
chloric acid, and zo c.c. of 0*5 percent ferrocyanide. This 
was titrated with standard iodine, 6*Z5 c.c. of which vrere 
required, indicating o*oz97 grm. KCy (by theory, 0*02). 

(d) A solution from the ** zinc-boxes " was tested as fol- 
lows : — zo C.C. of solution and zo c.c. of 0*5 per 
cent ferrocyanide required 2*5 c.c. standard iodine. 
25 c.c. of solution and zo c.c. of 0*5 per cent ferro- 
cyanide required 6*25 c.c. standard iodine. 

Both tests indicating 0*0825 per cent KCy. 
JohaoDeaburg. July 3, 1893. 



Stody of certain Varieties of Graphite.— Henri 
Moissan.— The author has compared the graphite de- 
scribed in the foregoing paper with the graphite of Ceylon, 
Borrowdale, Ticondoroga, Greenville, Omesnack (Green- 
land), Mugrau (Bohemia), Scharzbach, and South 
Australia. He concludes that the graphites occurring 
in nature may be classified, as proposed by Sn. Lnzzi, 
as sprouting and non-sprouting varieties. The former 
seem to have been produced oy the adion of melted 
baths, especially metallic baths. The latter may be due 
to the adtion of a high temperature 00 any kind of 
amorphous carbon.— Com^^/s Rtndut^ cxxi., No. 17. 



230 



specific Volume and the Genesis of the Elements. 



fORBMICALMBWt, 

I Mot. 8, 1695. 



SPECIFIC VOLUME AND THE GENESIS OF 

THE ELEMENTS. 

By C. T. BLANSHARD, M.A. 

As I anticipated in a recent article in this joarnal (Chem. 
News. Ixxi., p. 285), on ** Melting-points of the Elements 
as a Clue to their Genesis/* the question of Atomic and 
specific volumes provides a further clue. The atomic 
volumes of certain of the elements will be found to alter- 
nate in two different ways. It will also be found that the 
specific volumes, as calculated from observed specific 
gravities, in certain series of organic compounds, offer 
striking parallels to various conditions that maintain with 
the elements. 

To take the first case of alternation of atomic volumes 
of the elements. 

If the chemical elements are arranged in numbered 
series, we find in the eight series represented, that the 
atomic volumes (with the exceptions of the last three ele- 
ments in series 2, 6, and 10, and the first two in series 3) 
alternately rise and fall ; i.«., in the odd-numbered series 
the atomic volumes regularly rise, whilst in the even- 
numbered series the atomic volumes regularly fall. 



z. Hydrogen 1 


series. 












a. 


Li 


Be 


B 


C 


N 





F 


At. vol. 


ix-9 


4-9 


4-13 


3-41 


xs-6 


14-3 


— 


3* 


Na 


Mg 


Al 


Si 


P 


S 


CI 


At. vol. 


23-8 


13-9 


10-4 


irS 


141 


15-4 


a4'3 


4* 


K 


Ca 


Sc 


Ti 


V 


Cr 


Mn 


At. vol. 


44'9 


25*6 
Fe 


Co 


Ni 


9'3 


7-45 


7M5 


»» t> 




71 


6-9 


6-5 








5' 


Cu 


Zn 


Ga 


Ge 


As 


Se 


Br 


At. vol. 


70 


9-2 


ir8 


13*2 


15-9 


X7-6 


250 


6. 


Ru 


Sr 


Y 


Zx 


Nb 


Mo 


— 


At. vol. 


564 


33-9 
Ra 


Rh 


21-8? 

Pd 


13-3 


IX-2? 


~" 


ft »* 




80 


8*5 


8*8 








7- 


Ag 


Cd 


In 


Sn 


Sb 


Te 


I 


At. vol. 


I0'2 


X3*x 


153 


l6'2 


17-9 


19-5 


85-6 


8. 


Cs 


Ba 


La 


Ce 


Nd 


Pr 





At. vol. 


707 


365 


22'6 


2I'X 


— 


— 


— 


9. 


Sa 


— 


Gd 


Tb 


— 


Er 


— 


10. 


Dp 


Yb 


..^ 


— . 


Ta 


W 





At. vol. 




Os 


Ir 


Pt 


xr6 


9-8 




If »» 




8-5 


90 


9-x 








ZI. 


Au 


Hg 


Tl 


Pb 


Bi 


— 


— 


At. vol. 


10*2 


147 


17*2 


x8-2 


2X'4 


— 


— 


12. 


_ 


... 





Th 


— 


U 





At vol. 


— 


— 


— 


21X 


— 


X2-8 






Series 9 should prove to possess rising atomic volumes; 
that is to say, as the atomic weight increases there will 
be less and less corresponding increase in specific gravity. 
The figures for the atomic volumes are those calculated 
for a table given in Chem. News, vol. Ixx., p. 271, except 
that more recent values of barium (Ba = 137*43) and cad- 
mium (Cd = 1x2*06) are taken. 

The second way of showing the alternation of atomic 
volume is by comparing the elements in their natural 
groups and noting the diJ}erenc4S between the atomic 
volumes, as Bazaroff has done in the case of atomic 
weights. It will be seen that— 

X. The differences between the atomic volumes of ele- 
ments, taken in natural groups, alternate in groups I. and 
II., and probably also in III. and IV. 
2. In V. and VI. the differences increase with the in- 
case in atomic weight. 



3. In group VII. the differences are constant. 

4. In all the a and in all the b gronps the differeneei 
become less with increase in atomic weight. 

Diff. 
ii'9 
ax*i 
ix'5 
«4-3 



9-0 
117 

8-3 
127 



-15 

+1-8 

2*0 

35 
X15 

2'X2 
3*42 



07 
0*6 

3-25 
—0*05 

3*9 
1*6 

3*5 
1-9 

30 

2*0 



Groop. 
I. 


Element. 
Li 


At. vol. 
II-9 




Na 


238 




K 


449 




Rb 


564 




Cs 


707 


IL 


Be 


4*9 




Mg 


139 




Ca 


25-6 




Sr 


33'9 




Ba 


36-6 


IV.) 


Data too defeaive. 


V. 


N 


X5-6 




P(red) 


14X 




As (am.) 


X5-9 




Sb 


17*9 




Bi 


21-4 


VI. 





14*3 




S (rhom). 


1545 




Se (cryst.) 


I7'57 




Te (cryst.) 


19-99 


VII. 


F 


— 




CI 


24-3 




Br 


25-0 




I 


25*6 


I.n. 


Cu 


70 




Ag 


IO*25 




Au 


10*20 


II.fl. 


Zn 


9*2 




Cd 


X3'x 




Hg 


"47 


Ill.a. 


Ga 


xi-8 




In 


153 




Tl 


17*2 


IV.n. 


Ge 


X32 




Sn 


16*2 




Pb 


i8-2 



/ 



ChivicAlNbws,! 
Nov. 8,1895. 1 


VapouT'U 


Oronp. 


Element. 
V 


At. vol. 
9-31 




Nb 


13-3 


VLrt. 


Cr 


7'45 




Mo 


ii'iy? 




U 


12-79 


VILo. 


Mn 


7-45 


II.fr. 


Fe 


7-1 




Ro 


8-05 




o« 


8-50 


IV.6. 


Co 


6*89 




Rh 


850 




Ir 


8-97 


VIA. 


Ni 


6-53 




Pd 


8-77 




Pt 


9*o6 



Vapour 'tensions of Mixtures of Volatile Liquids. 



231 



Diff. 

3*99 

372 
I'Sa 



0*95 
0-45 

I -61 
047 

2*24 
0*29 



The c groaps do not supply any data, as, being Preyer's 
series xo and xx, at most each c group contains two ele- 
ments. Bnt it may be noted, in confirmation of Prof. 
Pre3rer'8 classification, which places Tantalum in what I 
term group V.c, instead of with Vanadium and Niobium 
in V.a; that the atomic volume of Ta, 17*6, shows a 
diilerence of 4*3 from that of Nb ; whereas, by the above 
laws of differences of atomic volumes, were Ta the third 
member of the group V.a, it would show a difference of 
considerably Uss than 3 '99, namely, a difference of about 
x-fi. The h groups in the above classification are Men- 
deleeCPs group, VIII. 

The a groups may be aptly termed the copptr, and b 
the iron groups. With regard to the differences in atomic 
vdume, it may be further noted that — 

5. In the ordinary groups the first differences are low, 
succeeded by higher ones. 

6. In the copper and iron groups (or a and b groups) 
the first diffierences are high, succeeded by lower ones. 

(To be continued). 



curves are, if we regard the right hand ordinate first, at 
the beginning parallel with the straight line connedinf 
the pomts representing the vapour-tensions of the pure 
liquids ; they then turn upwards, reach a maximum dis- 
tance from the straight line at about the abscissae value 
of fifty, and then gradually turn downwards towards the 
origin. I was curious to see if this behaviour was 
charaderistic of the mixtures of liquids investigated 1^ 
Raoult. B / 

Accordingly I have re*calculated his data so as to get 
them into a form comparable with mine. These re-calcu- 
lated data are given in the following small Tables :— 

Table A.^Vapour'TiHiions 0/ Solutions ofTurptntint in 
Eihir at 16-2^ 

Vapour-tension of Turpentine at 16*2° is 4 m.m. of 

Mercury. 

Vapour-tension of Ether at 16*2° is 377 m.m. of Mercury. 



ON THE VAPOUR-TENSIONS OF MIXTURES 

OF VOLATILE LIQUIDS.* 

Bz'C B. LINEBARGBR. 

(Continaed from p. 2x4). 

THe fouith class of mixtures, of which the only repre- 
sentative here is the mixture of nitrobenzene and carbon 
tetrachloride, does not, in reality, belong to our subjedt 
of investigation, which is to study mixtures of volatile 
liquids only, and not those of a volatile with an almost 
involatile one. Still it was thought advisable to find out 
what the partial tensions of mixtures of such liquids 
would be, inasmuch as Raoult {loc, cH.) has made an 
elaborate study of the total vapour-tension of mixtures of 
ether and several almost non-volatile liquids. As is seen 
in the curve, the partial pressure of the carbon tetra- 
chloride and the total pressure of the mixture are almost 
identical, just as would naturally be expeded. The 

* Abridced from the Journal of the American Chemical Society, 
vol. xvU., No. 8, August, 1895. 



Mols. of Turpentine in 


Vapour- tension in m.m! 


xoo molt, of solution. 


of Mercury. 


5-9 


354 


X2'X 


33a 


23-4 


294 


35-5 


255 


47*9 


212 


645 


159 



Tablb h.^Vapour-Tinsion of Solutions of Nitrob$n*tn$ 
in Ether at i6'oP. 

Vapour-tension of Nitrobenzene at x6'o^ is 4 m.m. of 

Mercury. 

Vapour-tension of Ether at 160° is 374 m.m. of Mercury. 

If oil. of Nitrobenzene in Vapour-tension in m.m. 

xoo mols. of solution. of Mercury. 

6*0 353 

17-9 32X 

35*5 278 

56*2 232 

75*9 x66 

84'o X32 

Table C.'-Vapour -Tensions of Solutions of Aniline in 
Ether at lyz"". 

Vapour-tension of Aniline at X5*3® is 4 m.m. of Mercury. 
Vapour-tension of Ether at 15*3° is 364 m.m. of Mercury. 



of Aniline in 


Vapour- tension in man. 


Is. of solution. 


of Mercury. 


3-8 


349 


77 


335 


148 


308 


30'5 


292 


49-6 


210 


687 


«47 



Table D.-'Vafour-Tension of Solutions of Methyl 
Salicylate in Ether at X4'2^ 

Vapour-tension of Methyl Salicylate at 14*2° is 4 m.m. of 

Mercury. 
Vapour-tension of Ether at 14*2'' is 306 m.m. of Mercury. 

Vapour- tension in m.m. 
of Mercury. 

344'6 



Mols. of Metbyl Salicylate in 
xoo mols. of solution. 



21 
4-8 
92 
15-1 
232 
49'0 
770 
85-0 



343*6 

3320 

3i6'0 

301-0 

28X 

208 

125 

lOX 



2i2 



Scientific Foundations oj Analytical Chemistry. 



fCBsyicALNiwi, 
t Nov. 8, 1895. 



Table E.—Vapouf'Tinsions of Solutions of Ethyl Btnzoate 
in Ether at 117°. 

Vapour- tension of Ethyl Benzoate at 117^ is 3 mm. of 

Mercury. 
Vapour-tension of Ether at 117° is 313 m.m. of Mercury. 

Vapour-tention in mjn. 
of Mercury. 

396 
286 
235 



Molt, of Ethyl Beozoate is 
xoo molt, of tolotton. 



4*9 
9-6 
27*1 
530 
75*5 
94'4 



167 
94 
39 



If these results be plotted in a system of co-ordinates, 
the curves will be found to have a close resemblance to 
the one which I have found for the mixture of nitroben- 
zene and carbon tetrachloride. It seems likely that this 
form of curve is the general one for the total tension of 
mixtures of a volatile with an almost fixed liquid. 
(To be cootiDoed). 



NOTICES OF BOOKS. 



The ScUntific Foundations of Analytical Chemistry treated 
in an Elementary Manner. By Wilhblm Ostwald, 
Ph.D., Professor of Chemistry in the University of 
Leipzig. Translated, with the Author's sanaion, by 
Gborob McGowan, Ph.D. 8vo., pp. 208. London and 
New York : Macmillan and Co. 1895. 
Professor Ostwald*s work here before us is clearlv 
distind from the other analytical manuals, large or small, 
with which we have come in contad. It is concerned 
not with technical details, but with fundamental principles. 
Hence, whilst it would not be consulted with reference to 
the best method of analysing a complex phosphate or 
titaniferous iron, or a cobalt ore, it may, and should be, 
considered not merely by the student, but by the experi- 
enced pra^itioner. 

We are here reminded that no substance is absolutely 
insoluble, and that none of our methods of separation and 
determination are perfed. Suggestions are thrown out 
which deserve notice. Thus, when speaking of the sepa- 
ration of solids from each other, the author mentions that 
mixtures of different substances in powder are eledrified 
on shaking, one constituent becoming positive and the 
other negative. If the mixture is thrown upon an eledri- 
fied non-conduAor, the oppositely charged particles are 
attraded to it and the others repelled. Again, in a non- 
homogeneous ele<5trical field the substances with the 
higher dieledric constants are driven to those spots where 
the intensity of the field is greatest. No analytical appli- 
cation of this fadi has yet been made. 

In speaking of the treatment of precipitates, attention 
is called to the phenomena of ncfsorption— not to be con- 
founded with adsorption. 

In the separation of gases from each other we are re- 
minded that not all possible methods have been tried in 
analysis. 

The theory of removing a dissolved substance from the 
solvent by shaking it up with another is clearly ex- 
pounded. It is shown that with a given quantity of sol- 
vent a more perfeA separation is effeded if the shaking up 
is done with many small successive portions rather than 
with a few large ones. 

Concerning heterogeneous equilibrium, the law is laid 
down that — ** In two contiguous spaces or phases the 
concentration of each substance present in both spaces 
must bear a constant ratio.'* 

It is admitted that the attempts made to determine the 
amount of a precipitate without washing it, from the 
mean specific gravity of precipitate plus liquid and the 



specific gravity of liquid alone, have led to no satisfadocy 
results. 

The second part of the book shows the application of 
the principles already laid down. Professor Ostwald re- 
peats that ** students who read this book will do so, not 
so much with the objeA of learning analytical chemistry 
from it, as of pondering over the scientific principles 
which underlie what they have already been taught by 
aaual praAice, so as to be able to apply this knowledge 
with greater freedom and certainty.** 

We can only hope that many students will thus ponder 
over these principles. 

We regret to find that Dr. McGowan uses as an abridg* 
ment for ** cubic centimetre,*' not the simple and unmis- 
takeable c.c, as used in France and hitherto in Britain, 
but the more prolix German expression ccm. 



Report of the Trinidad Government Analyst. Minute 
(No. 63) from the AAing Governor, accompanying the 
Annual Report of the Government Analyst for x894« 
Trinidad : Government Printing Office, Port-of- Spain. 
The total number of samples examined during the year 
was 653, of which 626 were official samples. The official 
samples were sent in by the police in connexion with 
cases before the Courts of Justice, from the sanitary police 
(food and drugs), the Customs, the Board of Health, the 
receiver-general, the surgeon -general, and Public Works. 
Of the official samples 78 were conneded with charges of 
murder, wounding, and indecent assaults ; and 69 were 
cases of susped^ed poisoning. In 38 of these samples 
poisons were deteded, namely arsenic, mercuric chloride, 
potassium cyanide, creosote, and preparations of opium. 
None of the insufficiently known poisonous prodnds of 
tropical countries seem to have been used. 

The adulteration of milk still requires constant vigilance, 
as 36 per cent of the total samples had been let down 
with water in the proportion of 25 per cent. Oleomarga- 
rine is sold at the same price as butter. 

We regret to find that the Colony is adopting the rec^t 
error of the home-kingdoms in requiring an addition of 
mineral oils to methylated spirits. Why not, as is done 
in Germany, make the methylated spirit undrinkable by 
the addition of a trace of DippePs animal oil ? 

The question of a regular baaeriological exaroinatioa 
of water supplied to Port-of-Spain is still under con- 
sideration. 

Some samples of water from wells in Tacarigoa dis- 
tria were found to be worse than many sewage effluents. 



Agricultural jfournal. Published by the Department of 

Agriculture of the Cape Colony. Vol. viii.. No. 17. 
Attention is emphatically called to the value of the sun- 
flower to farmers. It is found to bear the intense heat of 
central Australia better than any other crop. The seed 
is an excellent food for poultry. An acre of land yields 
50 bushels of seed, from which 50 gallons of oil may be 
obtained. The oil is excellent for lubricating, and for the 
manufacture of superior toilet soap, as well as for a clean- 
burning lamp-oil. The cake left after the expression of 
the oil is a good cattle-food, being considered in Eastern 
Europe as the best available cattle-food, superior to rape 
or hemp cake : 1000 lbs. of dried stalks have been found 
to yield 57 lbs. of ash, chiefly potash. Hence the stalks 
and leaves should always be ploughed into the soil. 

Particular attention is called to the war against the 
scale-insets {Coccida), which have already destroyed the 
orange and lemon plantations of South Africa. For 
dealing with these pests an emulsion of paraffin is recom- 
mended. A favourite formula is^ 

Paraffin 2 gallons. 

Soap lib. 

Water i gallon. 



CHBiaCAL Nbws, I 
Nov. 8, 1895. I 



Chemical Notices pom Forngfi Sources. 



233 



The water is heated to boiling, the soap stirred in until 
dissolved; when the mixture is just below a boiling heat 
the paraffin is stirred in with violent agitation for ten 
minutes. 



DftirminatioH oftk$ Atomic W tight of Cobalt, An In* 
angnral Dissertation presented to the Philosophical 
Faculty of the University of Basle for obtaining the 
Degree of Ph.D. By Hermann Thiblb. Submitted 
December 15th, X894. Basle: Kreis Printing Works. 
1895. 
Thb author, in criticising the researches of Remmler 
{Zeitsch. /. Anorg, Chtmii, ii., p. 222), points it out as a 
singular fad that the atomic weight of the several frac- 
tions operated on by the latter does not rise or fall pro- 
gressively, but fluftuates up and down. Remmler explains 
this fad by the presence in the fradions of different qnan- 
titles of an unknown element, as admitted by Kruss. 
Hence the investigation had even a greater importance 
than might have been supposed at first sight, though 
Dr. Tbiele did not find it useful to fraaionate the speci- 
mens employed in most of his experiments. 

He used three methods:—!, weighing cobaltous oxide 
and the metal; 2, cobaltous chloride and the metal; 
and 3, weighing the metal and silver chloride. The three 
determinations made by the first method give an average 
atomic weight = 58*849. By the second method, six de- 
terminations show an average a 58*64 ; and by the third 
method, four determinations gave a mean value of 58-801, 
or, with a corredion for the solubility of AgCl in water, 
58770. All the results are calculated for • 

a 15-96, C1^5'37, and Aga 107*66. 
The author's researches point to a probable value :— 
€0^58765. This result is compared with the most 
trustworthy recent determinations, f.#., those of Russell 
58*59, Lee 58*97, Zimmermann 5874, and Winkler 59 67. 
Hence it is pointed out that the author's result agrees ex- 
ceedingly well with that of Zimmermann, whilst the 
values of Russell and Lee diverge equally far on each side. 
Dr. Thiele*s results cannot be at all reconciled with that 
of Winkler. It is stated in a final note that this disser- 
tation was handed in to the Philosophical Faculty of 
Basle on December I5tb, 1894. Hence no reference could 
be made in it to the subsequent investigations of Winkler 
{Ziitseh.f, Anorg, Chtmit^ viii., p. 292). 
. Incidentally it is remarked that we can depend but 
little upon weights, originally extremely accurate, if they 
have been used for some time, however carefully. 

A careful examination of this pamphlet will convince 
the reader that Dr. Thiele has used every precaution. 
His weights (made by Verbeck, of Dresden) displayed, as 
far as those below xo grms. are concerned, only in two 
cases an error of 0-02 m.grm. The weights above 
zo grms. were used only for counterpoises, so that their 
absolute accuracy does not come in question. The balance 
was made by Bekel, of Hamburg, and had been carefully 
tested at regards the constancy of its zero-point. The 
vessels employed were of platinum, or, where this mate- 
rial was impraaicable, of Meissen porcelain, or of the 
so-called ** resistance glass *' of Koehler and Martini. 



Traniactions of the Wagner Free Institute of Science of 
Philadelphia. Vol. iii.. Part 3, March, 1895. Phila- 
delphia : Wagner Free Institute of Science. 
Thb issue before us is entirely devoted to geology and 
paleontology, and consequently contains no matter which 
rightfully falls within our purview. 

The Free Institute has a faculty comprising depart- 
ments of chemistry, botany and forestry, geology, physics 
and astronomy, literature and history, and engineering, 
Biology seems to have been overlooked. If we might so 
far presume we would suggest that a biological depart- 
ment should be established, and literatnre and history 



eliminated. We throw out this hint because we observe 
that in the so-called ** literary and philosophical societies'* 
of England, literature monopolises the lion's share of at- 
tention, and finds a space in the Transactions, 



Practical Proofs of Chemical Laws, A Course of Experi* 
ments upon the Combining Proportions of the Chemical 
Elements. By Vauohlan Cornish, M.Sc, Associate 
of the Owens College, Manchester. London and New 
York : Longmans, Green, and Co. 1895. Pp* 9^ 
If the multitude of works destined to throw a guiding 
light upon the course of the chemical student has any 
prophetical meaning, we ought soon to have a most luxu- 
riant harvest of discoverers and discoveries. Mr. Cornish 
admits, in his Preface, that the '* experimental proofs " 
might more properly be called ** verifications." Without 
doubt they constitute a useful series of exercises for stu- 
dents who are already acquainted with the qualitative 
composition of the substances employed, and as such the 
book deserves recommendation. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NoTB.~AII degrees of temperature are Centigrade unlets otherwise 
eipreued. 

CompUs Rmdus Hebdomadaires des Seances^ de VAcadetnie 
des Sciences, Vol. cxxi., No. 17, OAober 21, 1895. 

The Secretary announced the death of Dr. Hellriegel, 
a correspondent of the Sedion of Rural Economy, who 
died on September 24th last at Bernburg (Anhalt). M. 
Berthelot added that the deceased is distinguished for 
his beautiful researches on the fixation of nitrogen by 
leguminous plants, a phenomenon which he successfully 
traced to the aAion of baderia inhabiting certain nodosi- 
ties on the roots of the vegetables. 

Study of a Graphite Extra^ed from a Pegmatite.— 
Henri Moissan. — This paper will be inserted in full. 

Study of the Latent Heats of Evaporation of the 
Acetones of the Patty Series, OAaoe, Decane, and of 
the Two Ethers of Carbonic Acid.— W. Louguinine. — 
From his experiments the author concludes that for each 
of the groups which have been studied the volume of 
MS . . . 

—^ IS approximately constant. In this expression M 

represents the molecular weight of the substance, S its 
latent heat of evaporation, and T its absolute tempera- 
ture of ebullition. For different groups of substances it 
varies in a decided manner (from 26*5 to 19*8). 

Potassic Peroxidic Derivatives of Benxoquinone. 
— Ch. Astre. — The author's results show the diketonic 
nature of benzoquinone. 

Composition of the Rices Imported into Prance. — 
M. Balland. — Rice is a more nutritive aliment than is 
commonly supposed, and it would be advantageous to 
restrid the use of glazed rices, and to favour the consump- 
tion of the natural grain simply deprived of its husk. 

Toxicity of Acetylene.— M. Or6hant.— The author 
infers from his experiments that acetylene is poisonous if 
inhaled in large quantities. This gas can be easily de* 
teded in the blood by means of the ** grisometer.** It is, 
however, much less poisonous than coal-gas. Its mixtures 
with oxygen ate highly explosive. 

Bul'.eHn de la Societi Chimique de Paris. 
Series 3, Vols, xiii.-xiv.. No. 14, 1895. 
Aaioa of Nitrogen Peroxide upon the Haloid 
Salts of Antimony.— V. Thomas.— On dissolving a 



234 



Chemical Notices from Foreign Sources. 



I Chsmjcal Niwti 
I Nov. 8, 189s. 



haloid antimony salt either in chloroform or in carbon di- 
Bulphide, and passing into the solution a current of nitric 
oxide, we generally obtain a white crystalline precipitate, 
which, however, ceases to form after a certain time. The 
author thought that it might be due to traces of nitrous 
vapour. He took a stoppered flask, from which the air 
bad been carefully expelled by a current of carbonic acid, 
and containing a chloroform ic solution of antimony tri- 
chloride. Into this was passed a current of dry nitrous 
oxide, perfedly free from peroxide. No precipitate was 
formed until the flask was unstoppered, when it was im- 
mediately formed. The precipitate had the composition 
Sb40xxNaCl4. With tribromide dissolved in chloroform 
the result is analogous, but the precipitate contains no 
bromine, and has the composition Sb40z5N. 

Molecular Modifications of Glucose.—C. Tanret.— 
The author calls the ordinary glucose a, that which when 
crystallised gives the highest rotatory-power ao » + 106^ ; 
glucose P is the modification of a constant rotatory- power 
AD »+52*5°; and glucose y is that which gives at once 
the lowest rotatory-power ao « -f-aa'so*^. 

New Synthesis of Some Aromatic NitrileB.~A. 
Desprez. — The author has supposed that cyanogen, like 
chlorine, might be substituted for hydrogen in organic 
compounds. He applied the process for the present to 
five carbides, which he succeeded in transforming into 
nitriles, namely, benzene, toluene, two xylenes, and 
mesitylene. 

Causes of the Colouration and Coagulation of Milk 
by Heat. Formation of Formic Acid at the Expense 
of Laaose.— P. Cazeneuve and £. Haddon.—Already 
noticed. 



BulUtin de la SocUU d'Bncouragtment po 
NaiionaU. Series 4, Vol. x.. No 



Pour VIndustrit 
\o, 1x6. 

Combustion of Mineral Oils in Common Lamps.— 
P. Kouindjy. — This paper cannot be reproduced without 
the four accompanying figures. 

Matches with Explosive Pastes.— Th. Schloeting.— 
The entire replacement of phosphorus in the manufadure 
of matches does not seem to be as yet very near. Even 
the substitution of explosive pastes for those with white 

Ehosphorus is not so simple a matter as it might seem at 
rst sight. 



MISCELLANEOUS. 

Royal Institution.— A General Monthly Meeting of 
the Members of the Royal Institution was held on 
November 4th, Sir James Crichton-Browne presiding. 
The following were ele^ed Members :—H.R.H. Prince 
Louis Philippe, Due d'Orleans, Sir John Evans, K.C.B., 
F.R.S., The Hon. Adrian Verney Verney Cave. Mr. Walter 
Allcroft, and Mr. James Beale. The Managers reported 
that the late Mr. John Bell Sedgwick. M.R.I., had be* 
queathed £300 to the Royal Institution in aid of the Fund 
for the Promotion of Experimental Research at Low 
Temperatures. The special thanks of the Members were 
returned to Sir Frederick Abel. Bart., for his donation of 
£50 to the Fund for the Promotion of Experimental 
ReselEtfch at Low Temperatures. 

Conversazione at the Melbourne College of Phar. 
macy . — This veiy successful demonstration comprehended 
an exhibition of specimens and appliances bearing on 
pharmacy, such as plants of medicinal and technical in- 
terest, polariscopes and micro-spediroscopes (both instru- 
ments which ought to be more familiar to the pharmacist 
than they generally are), coUeaions of useful and destruc- 
tive inseds, baderiological specimens, fluorescent liquids, 
ftc. As an instance of utter irrelevance there figured a 
*< philatelic " coUeaion. A short ledure was given by 
Dr. F. Howell Cole on ** Toxins and Antitoxins," and one 
by Mr. Plowman on ** The Romance of Cocaine.*^ A 



prolonged investigation on a case of arsenical poisoniag 
did not involve any analytical question. In a prosecution 
at Adelaide, under the Food and Drugs Ad, the question 
was raised •• What is vinegar ? " The City Analyst held 
that vinegar for dietetic use should be composed of alco- 
hol, mucilage, extradive matter, acetic acid, and acetic 
ether. The University Analyst maintained that the term 
vinegar was a generic one, and should mean a naturally 
fermented vegetable infusion. Mr. Scammell declared 
that pure acetic acid and water was vinegar, and that fer- 
mentation was not necessary. — Tht Pkafmaautical 
youmal of Australasia, 

THIS DAY. Crown 8vo. 370 pages, 9s. cloth. 

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Explosive, and other Dangerous Compounds, their Storage and 
Transport, Official Claasifications. Parliamentary Boaaments. ht. 
By H. J. PHILLIPS, F.I.C., Author of '« Engineering Cfaemiftry.'* 

London: 
CROSBY LOCKWOOD and SON, 7, SfUone n' HaU Court, E«a 

Fourth Edition, Revised and EnUirged.i 

DESTRUCTIVE DISTILLATION : 

A Manualette of the Paraffin, Coal Tar, Rosin OiJ, sad kindied 

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By Professor E. J. MILLS, D.Sc., P.R.S. 

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} 



Graphite Extracted from Pegmatite, 



235 



THE CHEMICAL NEWS. 

Vol. LXXII., No. 1877. 



NOTE ON THB 

FORMATION OF CITRIC ACID BY THE 

OXIDATION OF CANE-SUGAR. 
By ALFRED B. SEARLE and AR^OLD R. TANKARD. 

SiNCB the publication of Dr. Phipson's third note on the 
formation of citric acid by the oxidation of cane-augar, 
we have continued our experimenta on this aubjed, and 
have attempted to obtain citric acid by a atrid adherence 
to the conditions last prescribed by Dr. Phipson (Chbm. 
News, vol. Ixxii., p. 190). 

Equal weights of cane-sugar, concentrated nitric acid 
(ap. gr. 1*42), and potassium permanganate were taken, 
the last-named reagent being added in the form of a 
strong aqueous solution. The liquid became as clear 
as water in about half an hour after the last addi- 
tion of permanganate. This solution was then allowed 
to stand for twenty-four hours, and at the end of that 
time was neutralised by the cautioua addition of chalk, 
the liquid being frequently agitated. When the liquid 
ceased to have an acid readion to litmus, it was filtered 
and the filtrate boiled for some minutes. No precipitate 
was produced even after the addition of a strong solution 
of calcium chloride and further boiling, thus showing the 
absence of any notable quantity of citrate. 

The mauer on the filter diasolved with iffitvisanci in 
acetic acid, showing that an excess of calcium carbonate 
had been used. We fail to see how Dr. Phipson avoided 
the use of an excess of calcium carbonate in neutralising 
the acid solution. 

Wflgfeve also used sulphuric acid in place of nitric 
aciiVflncidulating the cane-sugar solution. In this case, 
the cleaf solution, after standing in the cold for twenty* 
four hoars, was neutralised by the addition of chalk, and 
filtered. This filtrate, on boiling for some time, deposited 
a white crystalline precipitate, which was filtered off 
and washed with hot water. It was then dried at 100^ C, 
and BubjeAed to such tests as were described in our pre- 
vious paper (Chbmical Nbws, vol. Isxii., p. 31). 

The results in every resped confirmed those formerly 
obtained, and showed the substance to be composed 
entirely of hydrated calcium sulphate, CaS04.2HaO. 

Dr. Fhipaon, in his third note (Chemical News, vol. 
Izxii., p. xoo),statea that it is easy to point out where our 
error lies, but that it will perhaps not be so easy to get 
OS to acknowledge it. We do not deny that citric acid 
may be formed by the oxidation of cane-augar under 
suitable conditions, but we do assert that the mode of 
operating prescribed by Dr. Phipson fails to produce citric 
acid. 

We notice that Dr. Phipson's first note on this subjed 
(Chemical News, vol. Ixxi., p. 296) was entitled ** The 
Produdion of Citric Acid by the Oxidation of Cane<8ugar.** 
His second note was headed **0n the Prododion of 
Citric Acid from Cane-sugar." His third note, however, 
has the heading '* Citric and Tartaric Acids from Cane- 
sugar,*' and, indeed, this note seems to be mostly con- 
cerned with the formation of tartaric acid, whilst citric 
acid receives very bare mention. We do not dispute the 
fad that tartaric acid is a produd of the oxidation of cane- 
augar. Many obaervers have confirmed this ; in fad, in 
hia second note. Dr. Phipson gives references. But Dr. 
Phipson appears to be diverging from the question 
originally at issue, namely. Can citnc acid be produced by 
the oxidation of cane-sugar und$r tht abovi conditions ? 

Dr. Phipson states (Chemical News, vol. Ixxii., p. zoo) 
that we firat failed be^auae we used too much sulphuric 



acid ; then, because we did not separate the organic acid 
by alcohol ; and thirdly, because we used an insufficient 
quantity of permanganate (Chemical News, vol. Ixxii., 
p. 190). The first and last of these objedions, which 
have reference to the relative amounts of reagents em- 
ployed, are now removed by the description of the pro- 
cess given by Dr. Phipson in his third note, hot still wo 
obtain no citric acid 1 

Regarding the use of alcohol for the separation of the 
organic acid, if it is so necessary for the success of the 
experiment as Dr. Phipson implies in his second note, it 
is strange that all mention of alcohol is omitted from his 
third note. 

From the results of our experiments we are bound to 
conclude that citric acid cannot be obtained by the oxida- 
tion of cane-augar in the manner preacribed by Dr. 
Phipson, and we observe that Mr. E. F. Hicks (Chem. 
News, vol. Ixxii., p. 165) has independently arrived at the 
same conclusion. 

67, Snrrey Street, Sbeffieldi 
November 4, 1895. 



STUDY OF THE GRAPHITE EXTRACTED 

FROM PEGMATITE. 

By HENRI MOISSAN. 

We have established in previous researches that a suffi- 
cient rise of temperature at the ordinary pressure converts 
every variety of carbon into graphite. We have further 
shown that all the graphites produced in a bath of melted 
metal (iron, chrome, tungsten, molybdenum, vanadium, 
platinum, ftc.) aprout. On the contrary, the graphites 
obtained by the volatilisation of carbon in the eledric arc 
or by a simple thermic tranaformation do not present the 
propertv of sprouting when heated after the addition of a 
trace of nitric acid. These researches have led us to re« 
sume the study of some natural graphites. 

It is known that Berthelot has given the following 
definition of graphite :— ** Every varietv of carbon capable 
of yielding a graphitic oxide on oxidation." 

This graphitic oxide is most commonly obtained by 
Brodie's method on submitting graphite to the aAion of 
a mixture of potassium chlorate and nitric acid. We ob- 
serve that on projedin^ very dry potassium chlorate into 
very concentrated nitnc acid it dissolves instantly with 
an orange-red colouration, and under these conditions, 
whatever variety of graphite is used, we obtain at the 
temperature of 6o^ after an adion of ten hours, an entire 
transformation into graphitic oxide. The slightest trace 
of moisture prevents this red colouration, and greatly 
diminishes the speed of the transformation. 

The specimen of graphite which I have studied was ob- 
tained from a pegmatite from America without specifica- 
tion of the locality. 

This pegmatite is highly interesting, since we know 
that this eruptive rock has reached the surface after 
having reached a high temperature. 

In this specimen the graphite appears in fine laminar 
crystals, the sides of which often measure more than a 
centimetre, and are intimately distributed throughout the 
enrire mass. It is easy to separate the graphite by treating 
the rock in its native state repeatedly in the water-bath with 
hydrofluoric acid at a concentration of 50 per cent. All 
the felspar and silica quickly disappear. The residual 
matter is washed with boiling water and dried in the 
stove. 

The pegmatite studied contained Z377 per cent of 
graphite. The fine laminn thus obtained are flexible, 
specular, and present a surface showing strin and eqoi- 
lateral triansular impressions, perfedly characteristic. 

This graphite takes fire in oxygen at the temperature 
of 690*; it yielded 5*01 per cent of ashes, composed 
chiefly of silica, alumina, and lime, and traces of iron. 



236 



Detection and Determination oj Calcium Chlorate. 



rCMBMicAt Nbw>. 
I Nov. 15, 1895. 



Thii last metal bat bMn deteAed by means of potassium 
snlpbocyanide and ferrocyanide. The ash is white, and 
retains the form of the crystals of graphite. Its tempera- 
ture of combustion is higher than that of the graphites 
of Scharsbach or of Ceylon. 

This graphite sprouts. If it is moistened with mono- 
hydrated nitric acid, as Sn. Luzzi recommends, and then 
heated to dull redness, it sprouts abundantly. 

If this graphite is treated with the oxidising mixture of 
potassium chlorate and of monohydrated nitric acid in 
large excess, there is presented a very curious pheno- 
menon. We placed 6 grms. of graphite in a flask holding 
500 C.C along with a pinch of potassium chlorate and 
about 30 c.c. of nitric acid. At the outset of the readion 
the graphite takes a fine greenish tint, due to a super- 
ficial readion, and after some hours it increases in bulk 
in the liquid so as to fill half the flask. On a second 
attack it continues to sprout, and its bulk increases so 
that the vessel must be changed. This is the only 
eraphite which in a liquid like nitric acid gives such an 
mcrease of volume at the temperature of 6o^ After the 
deflagration of the graphitic oxide and its destruftion, we 
did not find in the residue any trace of diamond, either 
black or transparent. 

On the seventh attack with the oxidising mixture, the 
transformation into light green graphitic oxide is com- 
plete, but on a succeeding attack the graphitic oxide is 
absolutely decolourised. 

On examining with a low microscopic power the frag- 
ments of quartz or of felspar to which the crystals of 
graphite were attached, I was much surprised to see that 
they presented impressions the exad image of the surface 
of these crystals. There are the same strise and the 
same triangles, which a very energetic fridion cannot re- 
move. 

This fad leads us to think that the graphite existed 
prior to the rocks which produced pegmatite by their 
crystallisation. This graphite, by its charaderistic pro- 
perties, completely recalls the specimens obtained in 
metals in a state of fusion in an eledric furnace. It must 
have been produced under the same conditions, and at 
the moment of formation of pegmatite it has been 
moulded by the crystals of quartz and of felspar, and has 
left upon the latter the impression found upon its surface. 
— CompUs Hindus^ csxi., p. 538. 



A NEW SPECTRAL PHOTOMETER. 
By A. KCENIG. 

Betwbbn the collimator* tube, which has the superjacent 
slits always of equal width, and the eye-tube there is 
introduced a flint-glass prism, and further towards the 
eye-piece a twin>prism ; that is, a combination of two 
flat prisms, touching each other with their thick ends (such, 
#.^., as are used in Fresnel's interference experiment), 
and towards the collimator a so-called Rochon*8 prism. 
By means of this arrangement there are produced eight 
spedra, in one plane of which three times two each coin- 
cide with each other, and of which each pair are polarised 
vertically to one another. In the plane in which the 
spedra appear there is a diaphragm which, at the spot 
where two spedra polarised vertically to each other coin- 
cide, postetses a slit, through which therefore a given 
colour it cut out of both prisms. If we look through the 
slit towards the twin prism its entire surface is illuminated 
with spedral light, and we see the upper half of the field 
of vision illuminated with light of the one spedrum, and 
the lower half with the light of the other. By turning 
the telescope we can see through the slit another colour 
of both spedra, so that the observation can be effeded for 
each colour. If we have only one source of light for both 
slits, or if we cause two sources of light of equal bright- 
ness to ad upon one of the slits, there ensues a shght 



loss in consequence of therefledion within the apparatus, 
and the two semicircles are not equally illuminated. If 
we now interpose a Nicol prism between the telescope 
and the slit in the diaphragm upon which the spedra fall, 
we can produce an e(}ual brightness of both fields of 
vision by turning the Nicol prism. If the sources of light 
which throw the light into each of the two slits are of 
different intensity, we can have an equal intensity by 
another rotation of the Nicol prism. The proportion of 
the illuminations can be deduced from the angle of deflec- 
tion.— i4iiiia/«fi d$f Physik und Chimii, and Zeit, fur 
AnalytUchs ChimU, 



ON THB 

INFLUENCE OF SALTS UPON THE 

BEHAVIOUR OF INVERT-SUGAR WITH THE 

ALKALINE SOLUTION OF COPPER. 

By ARTHUR BORNTRAGBR. 

The author gives an experimental study of the questioa 
whether the presence of salts has any effed upon the de- 
termination of invert-sugar by the Fehling - Soxhlet 
method. He concludes that of the salts which are here 
concerned those having a neutral readion with litmos 
(sodium and potassium chlorides, sodium sulphate and 
acetate) have no effed upon the redudive power of solu- 
tions of invert-sugar, either immediately or on prolonged 
con tad in the cold, or on evaporation. 

On the contrary, it appears that the salts having an 
alkaline readion with litmus (such as sodium carbonate 
and phosphate) can, by their mere presence, increase the 
redudive adion of invert-sugar. In the case of soda« it 
further appeared that a prolonged adion in the cold hat 
the opposite effed, decreasing this power. Sodium phos- 
phate has no such effed on prolonged adion in the cold, 
but on evaporation. — Diutschs Zucktr Industriit 1894, 
pp. 1529. 1563. 



DETECTION AND DETERMINATION 

OF CALCIUM CHLORATE IN CHLORIDE 

OF LIME. 

By R. FRBSENIUS. 

Even in recently-prepared chloride of lime caldam 
chlorate is often present when the calcium hvdroxide ex- 
posed to the chlorine contained calcium carbonate. In 
this case hvpochlorous acid is liberated, and is quickly 
decomposed, with formation of chloric acid. Lunge and 
Schoch found [Btrichttt 1887, p. 1477) in a very carefully 
prepared chloride of lime 0*20 per cent of chlorine in the 
state of chlorate. In old chloride of lime calcium chlorate 
is almost always present, as appears from the experiments 
of Pattinson {jfoum, Soc» Chem, Industry ^ 1888). He pre- 
served specimens for a year in twelve small stoppered 
bottles, each holding xao grms. at 21 i^ and 266^, and 
determined every month the chlorine present in the state 
of chlorate in one of the bottles. The chlorine present in 
this state increased from 0*09 to 0*43 per cent in the 
samples preserved at 21'x'*; and in thuse kept at 26*6^ 
up to 1*37 per cent. The striking circumstance that in 
the former series the samples examined in April, May, 
June, and July contained no chloric acid; and in the 
second series mere traces of chloric acid were found in 
April and May ; and that in the second series, in Odober 
1*45 per cent, in November z-29, and in December 1*37 
of chlorine were found in the state of chloric acid 
might be due to the manner in which the chloric acid 
was determined. Pattinson added to the specimen of 
chloride of lime suspended in water aqueous sulphurous 



Mov. 15, 1895. f 



specific Volume and the Genesis of the Elements. 



237 



add, heated to ebullition, added after the expulsion of 
the chief part of the excess of the sulphurous acid a few 
drops of nitric acid for its complete elimination, neutral- 
ised with calcium carbonate, determined the total chlorine 
by titration with silver nitrate, and subtraded from this 
value the sum of the chlorine present in the bleaching 
sute and as a chloride. The small quantity of chlorine 
present in the state of a chlorate was calculated from the 
difiereoce ; that is, by a method in which the inevitable 
inaccuracies in the determination of the large quantity 
of chlorine present in the bleaching state and of the 
chlorine found as calcium chloride must greatly interfere 
with a precise estimation of the small quantity of chloric 
add. 

As the ouestion often occurs to chemists whether a 
chloride of lime contains calcium chlorate, and if so, what 
quantity ? 1 have sought to elaborate a simple procedure 
for its direA detedion and determination. 

It depends upon the fad that the hypochlorites are de- 
composed by lead acetate with the simultaneous forma- 
tion of lead peroxide, whilst chlorates remain unchanged ; 
it is convenient to proceed as follows : — 

We grind up finely 10 grms. of chloride of lime with a 
little water, adding gradually more water, rinse the whole 
into a litre flask, fill up to the neck, shake up well, allow 
It to subside, filter through a dry filter-paper, and use 50 
cc of the filtrate for the detedion of chloric acid, or for 
its determination. 

In either case we mix the measured 50 c.c. of the solu- 
tion in a boiling flask with a solution of neutral lead 
aceute in some excess. There is formed at first a white 
predpitate of lead chloride' and lead hydroxide, which, in 
cooaeqoeace of the adion of the hypochlorite upon the 
lead chloride, becomes yellow and then brown, with libera- 
tion of chlorine, and passes into lead peroxide — 

Ca(C10)a+ PbCla« PbOa+CaCla+Cla. 
When the precipitate has subsided, we add a little more 
solution of neutral lead acetate in order to be certain that 
the lead salt is present in excess, and if a further precipi- 
tation takes place we add still more of the solution of 
lead acetate. 

We now allow the mixture to stand, preferably in an 
unstoppered boiling flask, with fre<iuent agitation^ when 
the odour of chlorine gradually disappears; in part by 
evaporation, but chiefly by ading upon the excess of lead 
acetate, forming lead chloride and peroxide and free 
acetic acid^ 

aPb(CaHsOa)a+Cla+2HaO-PbCla+PbOa+4CaH40a. 
The odour of chlorine disappears completely in about 
eight to ten hours. 

If it is merely requisite to recognise chloric acid, we 
filter off the predpitate, remove the lead oxide from the 
filtrate t>y adding dilute sulphuric acid in slight excess, 
filter, mix the filtrate with a small quantity of solution of 
indigo, and then add, drop by drop, a small quantity of a 
solution of sulphurous add in water. If chloric acid is 
present, it is reduced by the sulphurous acid and the 
lower oxides of chlorine, or if the redu^on hat proceeded 
farther the chlorine destroys the indigo blue. 

That an excess of sulphurous add must be avoided is 
manifest, since in that case the a^on of the chlorine must 
be annulled ; the chlorine being converted into hydro- 
chloric acid by the decomposition of water and the forma- 
tion of sulphuric acid. 

Of the fad that no chloric add is formed in the above 
process I satisfied myself by repeatedly preparing solutions 
of chloride of lime by mixing chlorine water with an ex- 
cess of milk of lime, filtering, and treating the filtrate 
with solution of lead acetate, as above direded. In the 
solutions of chloride of lime thus obtained no chloric acid 
was ever deteded. 

If chloric acid is to be determined quantitatively, we 
wash the precipiute of lead chloride and lead peroxide 
until the washing water has no longer an acid readion. 
The washings are somewhat concentrated by evapora- 



tion, added to the filtrate, the litjuid is mixed with a 
solution of sodium carbonate in slight excess ; after some 
time the precipitate of lead and calcium carbonates is 
filtered off, washed, evaporated nearly to dryness on the 
water-bath, introduced into a small flask, and the 
chloric acid is determined according to Bunsen's method, 
by heating with concentrated hydrochloric acid, convey- 
ing the gases given off into a solution of potassium 
iodide, and determining the iodine liberated with sodium 
hyposulphite or by Fiokener*s modification. Six equiva- 
lents of iodine liberated correspond to one equivalent of 
chloric add. — Ziii. f. Analytisehi Chimii, 



SPECIFIC VOLUME AND THE GENESIS OF 

THE ELEMENTS. 

By C. T. BLANSHARD, M.A. 

(Concluded from p. 231). 

Wb will now enquire, though with very meagre data to 
work upon, what light organic chemistry has to throw on 
the evolution of the elements, from the point of view of 
differences in specific volume. All specific gravities are 
taken at 15° C. 

Normal Primary Alcohols, 

(Sp. grs. in this list and the next from Meyer and Jacobsoo» 
Lihrbuch dsr organ. Chimii^ Leipsig, 1893). 

Formula. Sp, icr. Sp.vol. Diff. 

CH3.OH o-8i2 3970 

«737 
CaHs-OH o-8o6 57'07 

16-54 
C3H7.OH 08x7 73 6x 

16*30 
C4H9.OH 0823 89-91 

16*20 
C5H11.OH 0829 Z06-X 

X63 

C6H13.OH 0-833 X22-4 

x6*3 
CyHij.OH 0836 1387 

i6*a 
C8H17.OH.. •• .. 0839 X54'9 

X7*i 
C9H19.OH 0*842 i7X*o 

«r3 

CioHai.OH .. .. 0*839 x88*3 
The differences are nearly constant. 

Normal Halogtn EsUn. 

Fonnula. Sp.gr. Sp.vol. Diff. 

CH3.CI 0*952 5299 

17*22 
CaHs.Cl 0*9x8 70*21 

«579 
C3H7.CI 0*9x2 86-00 

15*93 
C4H9.CI 0*907 iox'93 

X5'94 
CsHu.Cl 0901 X1787 

X7*x6 
CeHtj.Cl 0*892 X35-03 

X7-58 
C7H15.CI 0-88X 15261 

1609 
C8Ht7.CI 0*880 x68*70 

Differences nearly constant ; with the exception of the 
fourth and fifth they alternate. 



238 



Vapour-tensions of Mixtures of Volatile Liquids. 



I Cbkmical Ntwt, 
1 Not. 15, 1895. 



Normal Fatty Acids. 

(Specific gravities from Landolt and Bftrnstein, Pkys, 
chimischi TabilUn, Berlin, 1894 ; except the last four, 
from Meyer and Jacobson). 



FormaU. 


Sp.gr. 


Sp.vol. 


Diff. 


H.COaH 


r245 


3695 


18-60 


CHs.CO,H .. .. 


i'o8o 


55-55 


X875 


CaHj.COaH .. ., 


0-996 


7430 


17-46 


CsHyXOaH .. ., 


0-959 


91-76 


14-71 


C4H9.COaH .. .. 


0958 


106-47 








16-28 


C5H„.C0aH.. .. 


0-945 


12275 


18-40 


C6H,3.COaH .. .. 


0*921 


141-15 


16-23 


CyHisXCaH .. ., 


0-915 


157*38 


Z6-64 


C8Hx7.COaH .. .. 


9-908 


174-02 








9*35 


CgRxg-COaH .. .. 


9938 


183-37 





The differences alternate, except the fourth. Ostwald, 
in his Lekrhuch dir Alg. Chtmii, vol. ii., Stocbiometrie, 
p. 360, &c., ffives a few sach tables; but they differ 
rather widely uom these calculations, nor are they nearly 
so complete. 

To take as an example the fatty acid series ; Ostwald 
gives- 



Formic acid • 
Acetic acid 
Propionic acid. 
Butyric acid • 
Valeric acid . 



Sp. vol. 
41-4 

637 

854 
107*1 
130-7 



Diff. 
22*3 
21-7 
2X-7 
23-6 



According to Ostwald, and all other observers hitherto, 
the specific volumes of organic compounds are regarded 
as rising by constant increments ; or, in other words, the 
differences between the specific volumes are regarded as 
approximately constant. 

But we have seen that, whilst in the case of the normal 
primary alcohols the differences are nearly constant, there 
is a more marked alternation of differences in the chlorin- 
ated and oxidised series of compounds. Further, we shall 
find in certain fatty acid esters, and in certain aromatic 
series, whether chlorinated or not, the same alternation 
noticeable. 

Normal Aettic Esttrs, 

(Specific gravities from Landolt and Bdmstein). 
Sp. gr. Sp. vol. Diff. 



Methyl 


acetate 




0-956 


7739 


ao-59 


Ethyl 


>• 




0-898 


97-98 


I4'xx 


Propyl 


f» 




0-910 


z 12*09 


20-z8 


Butyl 


II 




0-877 


132*27 


12*82 


Amyl 


»i 




0896 


145-09 





We learn from these tables of specific volumes, the 
most representative that I have been able to collate, that 
— z. Organic groups behave like the a and b groups of the 
elements, havmg their first differences high ; 2. Except 
the fatty acid series and the chloro-benxene series. 



Normal Binuitu Hydrocarbons. 

(Specific gravities in this and the next Table are from 
Beilstein, Handbuck d$r organ, CkimU^ Hamburg and 
Leipzig, Z895). 



FormoU. 



CeHe .. 
C6Hj.CHs 
CeHj-CaH, 
CeHj.CjH, 

C6H5.C4H9 
C6H5.C5H1Z 



Sp.gr. 
0*884 

0-871 

0-866 

0*870 

0*864 

0*864 



Sp. vol. 
88-2X 

105*62 

X22*40 

137-93 

Z55ZO 
Z7Z-3t 



The differences alternate, except the first. 

Cklorobinuems. 
Fortnnla. Sp. gr. Sp. vol. 

C6H5.CI Z-Z26 99*87 

C6H4.Cla, Z.2.. .. Z*320 ZZZ*29 

C6H3.CI3, Z.24 .. 1*465 Z25*25 



CeHa.CU, z.a.3.4 
C6H.CI5 .. .. 



Diff. 

1742 

z6*78 

15-53 

X7*Z7 
z6-2z 



Difl; 
IZ*42 
Z396 

5-4? 



z-842 Z35*86 



It is intelligible that in a highly oxidised series like the 
fatty acids, or a highly chlorinated one like the cbloro- 
benzenes, the specific volumes should be strongly modified 
by the chlorine or oxygen respedively. 

When I began this article— which has involved many 
hours' work— I had hoped to be able to demonsUate the 
greater or less degree of complexity of the so-called ele- 
ments by comparison with specific volumes of organic 
substances of known amounts of complexity ; but no such 
conclusions have been arrived at. I hope, however, that 
my partial success in the solution of this question niay 
lead other workers into the field. 



ON THE VAPOUR-TENSIONS OF MIXTURES 

OF VOLATILE LIQUIDS.* 

By C. E. LINEBARGER. 

(CooUnued from p. 232). 

Relations b§twe$n tke Concentrations in tke Gaseous and 

Liquid Pkases, 
The relations between the concentration in the gaseous 
and liquid phases is clearly shown by curves drawn in a 
system of co-ordinates, of which the axis of abscissA is 
taken for the representation of the molecular percentage 
composition of the liquid phase, and the axis of ordinatea 
for that of the gaseous phase. These curves are drawn 
in the figure, the data being taken from the first two 
columns of tables. 

As is seen, the curves prove to be very regular, and 
group themselves on either side of the diagonal of the 
square, according as the component chosen to increase 
from left to right in the diagram is more or less volatile 
than the other ; as this was taken to be the component 
containing a halogen, the curve is below the straight line 
when the halogen-containing liquid is less volatile than 
the other, and above when it is more volatile. 

Furthermore, the greater the difference in the volatility 
of the two liquids in the mixture the greater the curve* 
ture. It is very probable that mixtures of two normal 



* Abridsed from the Joutnal of the American ChemieeU Sode^ 
vol. zvii.. No. 8, Aufutt, 1693. 



CauftcAL Raws, I 
Nov. 15, 189s. I 



Chemical Researches and Spectroscopic Studies. 



239 




RBLATION8 BBTWBBN THB CONCBNTRATIONS IN LIQUID AND GaSBOUS PhASBS. 



liqaids with the same vftpoar leniion would give off 
▼apoora with identical composition in both liquid and 
gaeeons state. 

Ditcription of th$ Figun, 
AbicistA ■■ molecalei of one liquid in zoo molecules of 

mixture of liquids. 
Ordinates ■■ molecules of one vapour in 100 molecules 
of mixture of Vapours. 

Curve I Toluene-chloroform. 

„ II. •• .. •. Toluene-carbon tetrachloride. 

M III Benxene-chloroform. 

„ IV. .. .. •• Bensene-carbon tetrachloride. 

„ V Toluene-monochlorbensene. 

„ VI Benscne-monochlorbenxene. 

(To be coottoned). 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By JEAN SBRVAIS STAS. 

(Contioued from p. 227). 

On thi Holdns used for Fneing Bodies meant to he 

Volatilised^ from Accidental Contamination by Sodium* 
I PLACED on sheets of platinum, or on plates of purified 
carbon, plane or concave, fixed horisontallv, the metallic 
compounds on which I wished to turn a hydrogen and air, 
coal-gas and air, oxyhydrogen, or oxy -coal- gas blowpipe 
jet, to free them from accidental sodium impurities. 
When coming to each case in particular I shall mention, 
with necessary details, the measures I took for attaining 
this end. I will say, however, that the heat and draught 
produced by the flame of a hydrogen and air or an oxv- 
coal-gas blowpipe are amply sufficient to completely 
eliminate the sodium ; that the pressure of gas instde the 
blowpipe ought never to be more than four cm* of water, 
and that as a general rule a pressure of two cm, is ample. 



When one exceeds a pressure of <i cm., as is almost al- 
ways the case when using air delivered dired from a 
water-pump, the current carries away with it disintegrated 
particles of the compound, and involves thus the loss of 
the greater part of the body beine purified. 

When one uses a hydroeen and air or coal-gas and air 
blowpipe, the gases ought to be fed from gasometers 
counterweighted to exert the constant pressure wanted. 

The same remark applies to oxyhydrogen and oxy-coal- 
gas blowpipes, when they are used either to eliminate 
the sodium contained in compounds being experimented 
on, or to volatilise them for the purpose of making a 
speArum analysis of the flame saturated with their 
vapour. 

On the Holders used for introducing Compounds into 
Flames, Electric Sparks, Electric Discharges, and 
Electric Arcs, 

I necessarily had to adapt holders to the various condi* 
tions I had to satisfy. I will now describe shortly the ar- 
rangements I made with this objeA. 

A. On the Clips used to introduce and Volatilise Com* 
pounds in Flames whose Temperature is lb88 than the 
Melting-point of Platinum, — When it is required to intro- 
duce a compound to be vaporised into the flame of a 
Bunsen lamp, or into hydrogen burning in air, or into a 
vertical flame of a hydrogen and air or coal-gas and air 
blowpipe, I used an ordinary holder; that is to say, a very 
fine pure platinum wire, with the end simply turned up 
into a hook, or ending in a loop a or 3 m.m. diameter, or 
in a truncated spiral ; but when I forced the jet of hy- 
drogen burning in air, or of hydrogen and air, or of coal- 
gas and air, on to a compound to saturate the jet with its 
vapour, I placed the compound on a thin, plane or concave, 
plate of pure platinum. If the compound were friable 
and infusible, I coUeAed it into a conical heap from 5 to 
zo m.m. hi^h, on a plane platinum sheet, and having made 
the jet hortMontal I forced it on to the apex of the cone ; 
when the compound was fusible, whether decomposable 
or not by heat, I used a very concave sheet of pure platt* 



240 



Chemical Researches and Spectroscopic Studies. 



|cbbiiicai.nsws, 

\ Not. 15. 1*9$. 



num. In the centre of the hollow I pot a cone of very 
fonmt pure spongy platinum. The apex of the cone was 
from 5 to 6 m.m. above the plane snrface of the platinum 
iJieet. After having made the platinum sheet and the 
cone of spongy platinum red-hot, to get rid of accidental 
sodium impurities, I poured the melted compound on 
which I wished to operate over the cone, so as to com. 
pletely saturate it. I then forced the jet against the apex 
of the cone, taking care to begin with the point of the 
flame and end with the hottest part. 

B. On thi Holdin used to introduce and Volatilise 
Compounds in Flames whose Temperature approaches or 
equals the Fusing'point of Platinum. — The dark flame 
of hydrogen made incandescent by the introduAion of 
oxygen, without forming in it an inner cone, and the 
deep blue flame of coal-gas made light blue by the intro- 
dudion of oxygen, without making an inner cone, have 
the temperature mentioned above. For introducing a 
compound into these blowpipe flames, when vertical, I 
used a fine wire of pure platinum or of iridio-platinum 
containing 20 per cent of iridium, ending in a loop, and 
both overlaid with pure iridium, so as to stand a tempera- 
ture considerably above the melting-point of platinum. 
The iridio-platinum wire was made in 1878, by Mr. George 
Matthey, for the use of the International Committee on 
Weights and Measures. The iridio-platinum alloy con- 
taining 20 per cent of iridium is as malleable and dudile 
as pure platinum.* 

I succeeded in plating the platinum and the iridio- 
platinum wire witn a suitable coating of white iridium, 
perfedly adherent and partially combined with the plati- 
num and iridio-platinum, by powdering the wire— first 
moistened with glycerin — with iridium-black, and then 
putting it into a coal-gas and air blowpipe jet. By re- 
peatine this several times, according to the thickness 
wished, one can obtain wires ending in a loop or spiral, 
which stand perfe^ly well in an oxy-coal-gas blowpipe in 
which pure platinum wire melts. But if wires thus pre- 
pared have the advantage of resisting very high tempera- 
tures, they have the disadvantage of being brittle, or of 
becoming so after use, and of being very difficult to 
handle without breaking when one tries to make the body 
to be volatilised adhere to the loop, or to introduce it into 
the truncated spiral. 

Pure platinum wire does not alter the blue flame of a 
Bunsen burner, but a wire of platinum overlaid with 
iridium gives it a persistent violet-hlue tint ; this latter 
wire does not alter the light blue colour of incandescent 
hydrogen. SpeArum analysis of this last flame shows a 
continuous speArum identical with that shown by incan- 
descent hydrogen without an iridium-covered platinum 
wire — a clear proof that, at this extreme temperature, 
iridium neither oxidises nor volatilises, as is the case at a 
lower temperature, just as Sainte-Claire Deville, Debray, 
and I have found. 

One can procure iridium black suitable for this purpose 
by reducing chloro-iridiate of ammonium by hydrogen or 
coal-gas, at the low temperature of the volatilisation of 
chloride of ammonium, and replacing the hydrogen hy 
pure nitrogen as it cools. 

When I had to force a horisontal jet of incandescent 
hydrogen, or the light blue jet of an oxy-coal-gas blow- 
pipe on to a compound, in order to volatilise it, I made 
different arrangements, according as the body was 
fusible or infusible. When the body was friable aud 
infusible I made it into a conical heap on a plane 
sheet of platinum, or on a dish of purified retort carbon ; 
when, on the other hand, the compound was fusible, I 
poured it in a melted state over a cone of very porous 
spongy iridium, placed in a hollow formed in the middle 
either of a sheet of pure platinum or iridio-platinum, or 
plate of purified retort carbon, the top of the spongy 
iridium cone being from 5 to 6 m.m. above the sheet or 

* ** Report of the lotemational Committee on Weifbts asd Mea- 
•nrei." Meetiogt dariof 1878; Parie 1879. 



plate, exadly as I have described above. It is only 04 
sary to substitute a cone of spongy iridium for the 
of spongy platinum used in the former case. 

C. On the Clips used for introducing and VolatHisimg 
Compounds in Flames whose Temperature approaches or 
equals the Fusing-point of Iridium. — The inner cone of an 
oxyhydrogen or oxy-coal-gas blowpipe flame, when broo^t 
to a minimum length, is at the temperature mentioned 
above. When I introduced a compound into the in- 
terior of the inner cone of a vertical blowpipe flame, I 
completely covered with the compound either a strong 
filament of purified carbon ending in a sharp point, or m 
small rod of iridio-platinum with 80 per cent of iridiam 
forged at white heat, ending in a fine point overlaid with 
pure iridium. 

When the carbon filament is properly covered with m 
compound, which remains almost entirely on the surface, 
it resists, before being completely burnt, a sufficient length 
of time to permit a speArum analysis of the flame in 
which the compound is vaporised. 

The small-pointed iridio-platinum rods withao percent 
of platinum, and overlaid with pure iridium, resist mach 
longer before melting. The pointed end bends when ap- 
proaching the point of fusion, and thus tells automatically 
when it is necessary to remove it from the inner cone in 
order to save it from melting. 

When I wished to force the inner cone of an oxyhydro- 
gen or oxy-coal-gas flame, horijtontally, or nearly so, on 
to a compound to volatilise it, without contaminating ths 
holder with sodium, I met with great difficulties : to over- 
come these I had to resort to complex methods, which 
involved me in a long and expensive work, because it 
necessitated the preparation and employment of very 
considerable quantities of pure white iridium, of welded 
iridium jplates, and even of a cup of fused iridium. 

The first method consisted in the use of a flat plate of 
pure white iridium, 5 m.m. long, completely covering a 
disc of carbon which had been purified and freed from 
sodium, 3 cm. diameter by 5 m.m. thick, let in, to the 
depth of 6 m.m., to a hole made in a small block of pore 
magnesia compressed and hardened by being exposed to 
a white heat, made by the late Colonel Caroo. The 
magnesia block, before receiving the carbon disc, waa 
heated for some time in a coal-gas and sir blowpipe, to 
drive off the sodium obstinately held by magnesia even 
when it is free from silicic acid. 

Having warmed the white iridium plate, which waa 
raised from a to 3 m.m. above the top of the block of 
magnesia, in a coal-gas and air blowpipe, until all the 
sodium deposited by the air was driven off, I put in the 
middle ofthe plate, with platinum forceps, a small iridium 
dish, which had been welded in an oxv-coal-gas blowpipe 
flame, carrying either a core of an infusible compound or 
a hollow core of welded iridium, covered externally with 
the compound (oxychloride, sulphate, or carbonate) that 
I wanted to put into the inner cone of an oxyhydrogen or 
oxy-coal-gas blowpipe, in order to volatilise it and make 
a spedrum analysis of its vapour. 

The second method consisted in replacing the plate of 
white iridium, permeable by liquids, by a cup of 
fused iridium, not permeable by liquids, let in for half its 
height to a small block of pure magnesia, compressed 
and hardened at a sustained white heat, and heated in an 
oxy-coal-eas blowpipe until accidental sodium impurities 
were entirely driven off. The fused iridium cup was 
3 cm. diameter by 8 m.m. high. It was dished in the 
centre to a depth of 4 m.m., and weighed 102*800 grms. 
I owe the possession of this unique cup — without which 
it would have been impossible to raise the vapour of 
potassium, sodium, and lithium compounds to the tem- 
perature of the inner cone of an oxyhydrogen blowpipe 
flame — to the kindness of Mr. G. Matthey. When I used 
the cup, a hollow cone of welded iridium was put in the 
bottom of it. The top of this cone was about 2 m.m. 
above the edge of the cup. Having raised the cup and 
the contained cone in an oxy-coal-gas blowpipe flame to 



CsamoAL Nbwi, i 
Nov. t5» 1895. / 



Quantitative Determination of Perchlorates. 



241 



a temperature near the fusing- point of platinum, I filled 
it with the liquid compound meant to be volatilised ; at 
the same time I turned the inner cone of an oxyhydrogan 
biowfip^ flatms on to the top of the cone saturated with 
the liquid, whilst, with a conveniently placed spe^roscope, 
M. Rommelaere and 1 proceeded with the spedrum 
analysis of different parts of the flame charged with 
▼apoor. It several times happened that, on turning an 
oacyhydrogen blowpipe flame on to the top of the iridium 
cone in the iridium cup containing an alkaline chloride or 
sulphate heated to the fusing-point of platinum, these 
compounds exploded, and were thrown to some distance, 
scattering fiery drops about. To guard ourselves from 
danger, and to proted our instruments, we covered our- 
selves and the spedroscopes with wet cloths. 

Iridium undergoes no alteration by contad with 
chlorides and sulphates of potassium, sodium, and 
lithium, or even lithium oxide, when raised to the highest 
temperature attainable in an oxyhydrogen blowpipe 
flame. On the other hand, compounds of calcium, stron- 
tium, and barium always attack the surface of iridium, 
whether welded or fused. It produces thus at first 
coloured compounds, containing calcium, strontium, and 
barium. These compounds decompose finally, leaving 
the iridium with a roughened surface. 

I cleansed the articles which had been used in ex peri - 
menu by treating them first with very dilute hydrochloric 
acid, and then by keeping them for at least one hour in a 
mixture of equal parts of anhydrous bisulphates of 
potassium and sodium at a dull red heat. After having 
washed them thoroughly with water, I heated them in a 
coal gas and air blowpipe flame, until the^ showed no 
trace of the spedrum of the compound which had been 
in cootad with the iridium. 

(To be continued). 



THE QUANTITATIVE DETERMINATION OF 

PERCHLORATES* 

By D. ALBERT KRBIDER. 

The method usually employed for the quantitative deter- 
mination of perchlorates, by igniting to the chloride and 
weighing the halogen as the stiver salt, is indired and 
subjeA to error, especially as my experience proved, where 
the free acid is to be determined, and where, consequently, 
an alkali which is apt to contain chloride is used to form 
the salt for the ignition. To purify the salt for this me- 
thod only adds to the complication, and therefore a more 
satisfadory process was sought. In a recent article 
(Am$r, youm. of Sciinci^ vol. xlviii., p. 38) from this 
laboratory, by Prof, Oooch and myself, a method for the 
deletion of alkaline perchlorates sssociated with chlorides, 
chlorates, and nitrates was detailed, with mention of cer- 
tain efforts towards a quantitative determination. As 
throwing light upon the peculiar properties of per- 
chlorates, and as an introdu^ion to the satisfaAory 
method which I have finally developed, some of the re- 
sults of these earlier efforts will here be given. 

In studying the properties of perchloric acid in the form 
of its potassium salt, we found that when treated with 
potassium iodide in the presence of boiling phosphoric 
acid, no redudion of the perchlorate is efleded,— unless 
indeed, the boiling be continued till the temperature rises 
to 2x5® to 220° C, where the meta-phosphonc acid begins 
to form. But when the meta- phosphoric acid (made by 
heating the syrupy ortho-acid to 360° C.) is diredly ap- 
plied in the presence of potassium iodide, and kept at a 
temperature of about 200^ C, iodine is copiously evolved. 
To test this readion quantitatively, a number of experi- 
ments were made in an apparatus consisting of a retort, 



* Contributions from the Kent Chemical Laboratory of Yale Col- 
lege. From the Ammcan Joumai 0/ 5ci4nc4, vol. 1., OAober, 1893. 



KCIO« 
uken. 



into the tubulature of which a glass tube was carefully 
ground and prolonged so as to reach to the bottom of the 
bulb and serve for the passage of a current of carbon di- 
oxide, used to expel the air and carry the iodine into the 
receiver. The neck of the retort was bent so as to reach 
to the bottom of an Erlenmeyer receiving vessel, con- 
taining a solution of potassium iojide, which was trapped 
by a side-necked test-tube. After introducing the per- 
chlorate with the iodide and meta- phosphoric acid, all 
air was expelled by carbon dioxide and heat applied* 
The iodine colleded in the receiver was titrated with 
decinormal thiosulphate, from which the perchlorate was 
calculated. 

Table I. gives the results of several experiments per- 
formed in this way, which prove that even with a large 
excess of potassium iodide the perchlorate is so slowly 
reduced that the hydriodic acid escapes before the reduc- 
tion is completed. In order to delay the distillation of 
hydriodic acid until the perchlorate had been completely 
reduced, the potassium iodide of experiment (3) was intro- 
duced in a short tube sealed at one end, so that the 
meta-phosphoric acid could attack it only slowly, and the 
heat quickly raised to about 300*^ C , but evidently 
without advantage. In experiment (4) the iodide was 
introduced in the same way, but the heat was applied 
gradually and more moderately, with considerably im- 
proved results. 

Tablb I. 

HOPO, KI KC10« 

•*Md. Qted. found. Error. 

Ormt. Cm.* Grmi. Grm. Grm. 

(1) 0*1000 15 5'0 0*0741 0*0259- 

(2) 0*1000 17 ZO'O 0*0844 0*0156- 

(3) 0*1000 15 5*o 0*0364 0*0636- 

(4) o*xooo 15 5*0 0*0977 0*0023- 

A complete reduAion of the perchlorate evidently ne- 
cessiuted the means of introducing the iodide in sufiScient 
quantity and at will. 

For this purpose the tube serving for the introduAion 
of carbon dioxide was enlarged so as to hold the iodide, 
which could then be added to the solution at any time by 
a manipulation of the rubber conduAingtube for carbon 
dioxide, which would draw the acid up to the iodide, and, 
retreating, would carry back an easily regulated quantity 
of the latter. 

Table II. 
KCIO« taken. K I used. KCIO« foond. Error. 

Grm. Grmi. Grm. Grm. 

{5) 0*1000 5'0 0*0984 0*0016 — 

(6) O'looo 3*o 0*0924 0*0076- 

(7) 0*0500 2*0 0*0508 0'OOo8-|- 
(8» o*05«>o 2*0 0*0479 0*0021 — 
(9) o'looo 7*o 0*0977 0*0023- 

(10) 0*1000 3*o 00925 0*0075- 

(IX) O'XOOO 30 0*0999 O'OUOX- 

(X2) 0*1000 2'0 0*0994 O'00O6 — 

(X3) O'XOOO 4*o 00966 0*0034— 

Table II. gives a number of results obtained in this 
way. Experiments (xo), (zx), and (is) differed from the 
others only in the employment of a bulb pipette instead 
of the retort ; one end being bent so as to reach to the 
leceiver, and the other cut off rather short with a tube 
ground into it, serving the same purpose of conduding 
carbon dioxide and holding potassium iodide— the greater 
inclination of the potassium iodide tube made possible by 
this change appearing to offer advantages for the more 
gradual and regular mtrodudion' of the iodide. The 
amount of meta-phosphoric acid used was in all cases 
15 cm.". In experiment (X3) beat was applied by means 
of a bath kept at 230**. 

While several of these determinations gave only ad- 
missible errors, the irregularity of the remainder, and the 
uncertainty in striking just the proper conditions for 
good results, proved the method worthless, at least in, 
that shape. 



242 



Quantitative Determination oj Perchlorates. 



I CBBMtcAL Nswa, 
I Nov. 15, 189s. 



The experimeDti of Table III. record the results of 
adding the acid drop by drop to an intimate mixture of 
the powdered perchlorate and iodide kept hot. 





Table III. 




KC10« taken. 


KI taken. 


KC10« found. 


Error. 


Grm. 


Gnne. 


Grm. 


Grm. 


(14 O'XOOO 
(15) 0-0500 


40 


0*1036 


0*0036 + 


. 2*0 


0*0502 


0*0002+ 


(16) 0-0500 


30 


005x5 


0*00x5 + 



The high results of this Table doubtless point to the 
dissociation of hydriodic acid or to the partial reduftion 
of the meta-phosphoric acid in the temperature, which 
would na turally nse higher where so small an amount of 
liquid was present. But when the meta-phosphoric acid 
was there in greater amount, the distillation of the hy- 
driodic acid before the complete reduAion of the per- 
chlorate could not be prevented. 

An ordinary mixture having thus been found insufiScient 
to hold the hydriodic acid to the reduAion of perchlorates, 
a search for some compound in which the perchlorate 
could be fused with an excess of potassium iodide and the 
mixture thus obtained subjeAed to the adion of meta* 
phosphoric acid resulted m the employment of sine 
chloride. Anhydrous sine chloride was found to fuse at 
about 200° C. The perchlorate and iodide could be added 
to this fusion, and the whole melted, thoroughly diffused 
and cooled, without any evolution of iodine. This mass, 
when treated with meta-phosphoric acid in the apparatus 
previously employed, melted gradually with a copious 
evolution of iodine. 

Table IV. shows the quantitative a^ion. The amount 
of sine chloride used was roughly taken about equal to 
that of the iodide. 

Table IV. 



KC10« taken. 


KI taken. 


KC10« found. 


Error. 


Grm. 


Ormi. 


Grm. 


Grm. 


(17) 0*0500 


50 


0*0552 


0*0052 + 


(18) 0*0000 


50 


0*0044 


00044 + 


(xg) 0*0000 


4-0 


0*0057 


0*0057 + 



In (19) a mixture of cadmium iodide and potassium 
iodide, taken in the proportion of their molecular weights, 
was substituted for the sine chloride. The known salt 
corresponding to the formula Cdl3.2KI+2HaO was not 
so convenient, because of its high melting-point — 230° C. ; 
but when the two iodides are taken in the proportion of 
their molecular weights, the mixture fuses at about 200* C. 
Although this mass, after fusion, was more easily soluble 
than the xinc residue, the blank determination revealed a 
source of error equally disparaging. 

Gaseous hydriodic acid passed into a mixture of the 
perchlorate and meta-phosphoric acid at a temperature 
between aoo° and 300° C, was markedly less effedive 
than the generation of the acid on the spot ; and the dis- 
tilling of the perchloric acid by meta-phosphoric acid into 
a receiver of potassium iodide yielded oolv a trifling 
amount of iodine, while the passage of hydriodic acid 
over the fusing perchlorate in a short combustion tube was 
precluded by the high meltin|-point of the perchlorate 
endangering the dissociation of the halogen. 

The invariably high results obtained by the use of meta- 
phosphoric acid in all those experiments in which there 
was a reasonable assurance that the hydriodic acid was 
held till the perchlorate was completely broken up — 
experiments (X3), (14), (X5), (X7), (18). and (19) — indicated 
either a dissociation of hydriodic acid or a partial reduc- 
tion of the meta-phosphoric acid. Of the latter cause 
there were some grounds for suspicion, but, as its deter- 
mination ltd too far from the objed of the investigation, 
the use of phosphoric acid was abandoned. So far as our 
experience extended there remained, then, nothing among 
the reagents of the wet methods which was sufficiently 
aAive and stable enough to warrant its application. 
Fusion alone seemed capable of extrading the oxygen 



from the perchlorate. A number of preliminary tests 
were therefore made on certain salts of the halogens, us 
the hope of finding one which would be aded upon by 
the oxygen of the perchlorate with the liberation of thm 
halogen, which latter could be colleded in a receiver of 
potassium iodide and titrated with thiosulphate. 

The double chloride of aluminum and aodtom, 
AlaCl6.2NaCl, melu at about 200° C, and was in other 
respeds desirable. When fused with potassiom per- 
chlorate, chlorine was copiously evolved. The aAion of 
air on the fusion also liberated chlorine ; but blank deter- 
minations in an atmosphere of carbon dioxide proved that 
under these conditions not a trace of chlorine was 
evolved. The apparatus employed for a quantiutive teet 
of this reaAion on perchlorates consisted of a small dis- 
tilling flask of about 20 cm.* capacity, into the tubnlatare 
of which was ground a piece of glass tubing reaching 
well into the bulb, and serving for the passage of carboo 
dioxide. The side neck was sealed to one of two coo* 
neded Will and Varrentrapp absorption bulbs containing 
a solution of potassium iodide to receive the chlorine. 
After weighing the perchlorate into the flask, and adding 
a sufficient amount of the powdered double chloride, ell 
air was expelled by carbon dioxide, and heat applied 
till the fused mass was raised considerably above the 
melting-point and kept there for some time. Table V. 
contains the results of a number of experiments per- 
formed in this way. 

Tablb V. 



KC10« Uken. KC10« foond. 



(20) 
(21) 
(22) 
(23) 
(24) 
(25) 
(26) 



Grm. 
00500 
0*0500 
0*0500 
OII93 
0-X039 
0*0500 
0*1003 



Grm. 
0*0438 
0*0482 
p*046o 
OXX75 
o*xox8 
0*0477 
00946 



Error. 
Grm. 
0*0062- 
0'00X8- 
0*0040- 
0*00x8- 
0*002 X - 
0*0023 - 
0*0057 - 



These results came so close to beine quantitative that 
a little help in the form of free acid seemed all that 
would be necessary to complete the readion. But the 
addition of meta-phosphoric acid to the cooled mass after 
the fusion in (22) gave no additional evolution of iodine. 
In (25) gaseous hydrochloric acid was passed in with the 
carbon dioxide in the hope of meeting the deficiency, 
but was evidently no improvement. One test, in which 
meta-phosphoric acid was added to the fusion, restilted 
in such a violent evolution of hydrochloric acid that the 
whole contents of the flask was forced into the receivers. 

(To be continned). 



PROCEEDINGS OF SOCIETIES. 

PHYSICAL SOCIETY. 
Ordinary Mettingt Novtmhir 8M, 1895. 

Prof. A. W. ROcKBR, Vice-President, in the Chair. 

Mr. W. H. Evbrbtt read a paper on ** Thi Magmtic 
Field of any Cylindrical Coil or Plant Circuit." 

The method of treatment is based on the formula for 
the force due to an element of current. A single integra- 
tion applied to one component of this force gives for any 
point in the field due to a plane circuit the force perpen- 
dicular to its plane; and a double integration gives the 
longitudinal force at any point due to a cylindrical coil of 
any cross-sedion, the depth of winding being supposed 
inconsiderable. For coils in which the latter condition 
does not hold, an approximate solution can readily be 
found. THe force parallel to the plane of a circuit, and 
the transverse force due to a coil, are investigated in a 



CBBMICAL NbWS, 1 

KoT. xs» 1845. ' 



Latent Heat of Evaporation of Benzene. 



243 



■tmilar manner. The general resnlts are of a very simple 
form and admit of easy approximate calculation. Special 
formulae are deduced for coils of redaogular crosssedioo, 
the general expressions being in this case integrable. 

Appended to the paper are some numerical results 
giving the values of the forces at different points due to 
coils of various dimensions. 

Prof. Pbrry said he considered the paper to be a 
rmluable one, particularly as illustrating a praAical 
mathematical method of integrating. 

Mr. Trottbr said the paper was of interest to him, as 
he considered that several of the author's results might 
be applied to the solution of problems on illumination, 
cf., the illumination of a room by a circle of lamps. 

Mr. Rhodbs regretted that it had not been possible to 
supply a proof of the paper before the meeting. The 
method in which the author obtained the force outside a 
solenoid as the difference of the forces due to two 
solenoids reminded him of the method employed in cal- 
culating the attradion of, say, a truncated pyramid. 

Prof. SiLVANUS Thompson said the author had men- 
tioned several previous papers on the subjeA, but had not 
referred to one by Prof. Viriamu Jones, in which the force 
due to a solenoid is obtained in terms of elliptic integrals. 
Another method of attack was to calculate the work done 
when a unit pole is carried through the solenoid and back 
outside to the starting-point. 

Prof. Ayrton said he also regretted the absence of a 
proof of the paper. He considered it of great importance 
to have exa^ and simple methods of calculating the forces 
due to a solenoid. 

The Chairman (Prof. RdcxsR) said he had made a 
somewhat similar calculation in connexion with the 
magnetic effed of sheets of basalt below the surface of 
the earth. 

Mr. B. H. Griffiths read a paper, by himself and 
Miss Dorothy Marshall, on ** Thi Latint Hiat of 
Evaporation of BenMitti,^^ 

The method employed is similar to that used by one of 
the authors in the determination of the latent heat of 
evaporation of water (Phil, Trans* , 1895). The loss of 
heat due to the evaporation is balanced by (a) the heat 
supplied by an eledric current ; (6) a secondary supply 
due to the work done by the stirrer ; (c) a slight gain or 
loss due to small unavoidable changes in temperature of 
the calorimeter. The comparative values of the various 
sources of heat (if we denote the supply due to the 
eledrical current by 1000) is approximately : — Eledrical 
mooo; stirring dx; changes in calorimeter tempera- 
ture, ^. The eledrical supply could be measured with 
extreme accuracy, and the above table shows that small 
errors in the determination of the remaining thermal 
quantities are of little importance. The results may be 
summed up in the formula — 

L ■■ I07'05 — 0*1581 0; 
where B is the temperature, and the thermal unit at 15" C. 
is used. 

The discussion on this paper was postponed till after 
the reading of the following paper. 

•* On a Method of Comparing thi Heats of Evapora- 
tion of different Liquids at their Boiling-points," By Prof. 
Ramsay and Miss Marshall. 

The method employed has already been described be- 
fore the Society (Jan. nth, 1895). '^^^ liquid to be 
experimented on is put into a glass bulb enclosed in an 
outer jacket filled with the vapour of the same liquid. 
An open tube is attached to the top of the bulb, so that 
there is free communication between tke interior and the 
vapour-jacket, and no loss of material. Inside the bulb 
is a spiral of fine platinum wire, attached to stout plati- 
num terminals which are sealed into the glass. The 
temperature of the liquid in the bulb is raised to the 
boiling-point by the vapour-jacket ; thus when a current 
is sent through the wire the whole of the heat developed 
is spent in converting a portion of the liquid into vapour. 



Two such bulbs are conneded in series, and the ratio of 
their losses of weight is the inverse ratio of the heats of 
evaporation of the liquids. A corredion is made for the 
inequality in resistance of the spirals, and the ratio of the 
differences of potential between the ends of the spirals, 
when the current is passing, is determined in each experi- 
ment by PoggendorfTs method. Results are given for 
fourteen liquids. 
Prof. Ramsay drew special attention to the table 

ML 
giving the values of the quotient -t^, where M is the 

molecular weight, T the absolute temperature, and L the 
latent heat. Very curious differences are noticeable in 
the case of water, alcohol, and acetic acid. 

Prof. Carry Foster expressed his admiration for the 
method, since it obviated the necessity of knowing the 
specific heat of the liquid or vapour. 

Prof. SiLVANUS Thompson said the difficulty expe- 
rienced in the case of water, due to eledrolysis, might be 
obviated by the employment of a spiral of lower resist- 
ance and a larger current, so that the difference of poten- 
tial between the ends of the spiral should be less than 
17 volts. 

The Chairman said Captain Abney had asked him to 
enquire to what extent the temperature of the liquid was 
affeded by radiation. 

Mr. J. W. Rodger asked if any dired experiment had 
been made to determine if the temperature of the liquid 
was not above its true melting-point. In some cases 
differences of as much as 2^ might exist between the 
temperature of the liquid and that of the vapour given 

off. The differences in the value of -^ in the case of 

water, alcohol, and acetic acid might be due to the fad 
that the vapours of alcohol and water were simple, while 
the vapour of acetic acid was complex. 

Mr. R. Appleyard suggested that the differences ob- 
tained in the case of water might be due to the presence 
of dissolved air. 

Mr. Griffiths said that the objedion to the adoption 
of Prof. Thompson's suggestion was the fear that, with 
short wires, an excessive difference in temperature be- 
tween the wire and the liquid might exist. 

Mr. Rhodes asked if Mr. Griffiths could trust his 
determinations of temperature to to^oo^^ o( a degree ? 

Mr. Griffiths, in reply, said that he thought there was 
no limit to the accuracy with which a difference of tem- 
perature could be measured; the absolute temperature, 
however, he only relied upon to xo^oo^h o^ ^ degree. 

Prof. Ramsay said the fad of superheating existing 
would not affed the results, since near the temperatures 
at which they were working the latent heat did not vary 
appreciably with the temperature. In reply to Captain 
Abney, he said some previous experiments by Dr. Young 
and himself had shown that the vapour-jacket was quite 
impervious to radiant heat from without. 

Royal Institution. — The Christmas Course of Lec- 
tures, adapted to a juvenile auditory, at the Royal 
Institution, will be delivered this year by Professor John 
Gray McKendrick, M.D., LL.D., F.R.S., Professor of 
Physiology in the University of Glasgow, and formerly 
FuUerian Professor of Physiology in the Royal Institu- 
tion. The subjed will be " Sound, Hearing, and Speech,*' 
and the Ledures will be experimentally illustrated. The 
first Ledure will be delivered on Saturday, December aStb, 
at Three o'clock, and the remaining Ledures on Decem- 
ber 31st, 1895, ^°^ on January aod, 4th, 7th, and gtb, 
1896. 

Illuminating Apparatus for observing the Changes 
of Colour in Volumetric Analyses.— This apparatus 
has been construded by A. Lupp, and can be obtained 
from Kahler and Martini, of Berlin. In principle it is 
like an arrangement often employed in disseding micro- 
scopes. 



244 



Principles and Practice of Agricultural Analysis. [ 



Chmicai. Nswa, 
Kov. 15, i8qs 



NOTICES OF BOOKS. 



Aids to thi Analysis of Food and Drugs. By T. H. 

Pbarmain and C. O. Moorb, M.A., F.C.S., Members 

of the Society of Public AnalyitB. London : Bailli^re, 

Tindall, and Cox. Pp. 160. 
This little book at once commends itself to oar good 
wishes by its Preface. The authors say : — ** This work 
is not intended to be used as a cram-book for examina- 
tional purposes. We cannot emphasise too strongly the 
faA that food analysis is not to be taught in a few weeks, 
as is frequently attempted in the interest of public health 
students. A competent knowledge of the analysis of 
food and drugs is only to be obtained by some years of 
aAive praAical laboratory work." 

In treating of the analysis of milk, the authors remind 
us that the disgraceful state of the milk trade in this 
country is fostered, if not adually created, by the 
** absurdly low standard '* adopted by the Somerset House 
chemists who have been constituted the referees in adul- 
teration cases. They have fixed upon 275 per cent as 
the minimum for fat, and 8*5 for ** solid not fat." If we 
compare this standard with that adopted elsewhere, we 
find that it is exceptionally low. The State of New York 
requires fat 3 per cent ; New Jersey demands total solids 
X2 ; in Massachusetts the standard is 13 solids ; and in 
Berne total solids 12*5, and fat 3*5. 
. But there are other, and not less grave, errors in the 
** Sale of Food and Drugs Ad.'* Its scope needs to be 
enlarged, so as, e,g,, to bar the way to such quibbles as 
the well-known plea that baking powder was neither food 
nor a drug. The penalties are most absurdly low, and 
have merely a maximum limit which magistrates can 
and do at times reduce so as to render the punishment of 
the sophisticator pradically nil. 

In the matter of vinegar the authors seem to participi- 
pate in the common English notion that this condiment 
should be made from malt. Now the nitrogenous matter 
in malt or other grain cannot at all contribute to the pro- 
duAion of vinegar. It seems not improbable that the 
presence of dextrine tends to prevent the formation of 
those ethers which constitute the aroma of wine*, cider-, 
and sugar-vinegars. This theory, which merits experi- 
mental investigation, would account for the flatness of 
malt-vinegar. 

As regards pepper, it would be well if the importation 
of *'poivrette" and of its raw material—to wit, olive- 
stones—were totally prohibited. The estimation of the 
woody fibre seems to be a capital point in the analysis of 
peppers. The presence of lead chromate in any sub* 
stance intended for introduAion into the human system 
is a crime for which no money penalty is at all adequate. 

The analytical procedures here recommended are 
trustworthy, and indicate that the authors are not com- 
pilers, but men of experience. 



Tki Splash of a Drop. By Prof. A. M. Worthington, 
M.A., F.R.S. Being the Reprint of a Discourse deli- 
vered at the Royal Institution of Great Britain, May 
i8th, Z894. Published under the Diredion of the Gene- 
ral Literature Committee. London : Society for Pro- 
moting Christian Knowledge. 1895. Crown 8vo., pp. 76. 
Thb curious work before us discourses on the phenomena 
observed when a drop of water falls into milk; of a drop 
of mercury falling upon a hard, polished surface ; and of 
a drop of milk falling upon smoked glass. The author 
treats only of the mechanical phase of the question, 
leaving, for the present at least, the eledrical aspeA to 
other investigators, such as Lenard and J. J. Thomson. 
As to any possible chemical phenomena produced, the 
author is silent. 

Prof. Worthington has succeeded in reproducing the 
effeds produced by means of the instantaneous photo- 



graphic process. Thus the illustrations show* e.g., the 
appearances respeAively 0*0262, 0*0391, and oxox 
second after the contad of a drop of water with a surface 
of milk. Some of these figures decidedly remind us of 
the lunar craters as seen with the telescope. 



Principles and PracHci of Agricultural Analysis. A 

Manual for the Estimation of Soils, Fritilisers, and 

Agricultural ProduAs. For the Use of Analysts, 

Teachers, and Students of Agricultural Chemistry. 

Volume Ih^Fertilisers. By Harvey W. Wiley. 

Chemist of the U.S. Department of Agriculture. 

Svo,, pp. 332. Easton, Pennsylvania : Chemical 

Publishing Co. 1895. 
The appearance of this work is a striking proof of the 
great and enlightened attention paid to agriculture by the 
Government of the United States. The author's objed 
has been ** to present to the busy worker a broad view of 
a great subjed *' Those who merely want a book for 
routine work or in preparing for an examination are 
warned that they will here find little to attrad them. 

The present volume comprises four parts. The first 
treats of phosphates and phosphatic manures ; the second 
is concerned with nitrogen in manures and their com- 
ponents ; the third discusses potash as a manurial con- 
stituent ; and the fourth speaks of such minor fertilising 
materials as lime, gypsum, common salt, copperas, and 
wood-ashes. 

It will be at once seen that Mr. Wiley, like most 
British agricultural chemists, but unlike an eminent 
French authority, is far from placing lime in any form ia 
the same rank as the three great plant foods — nitrogen, 
phosphates, and potash. Whilst giving the general pre- 
ference to the molybdic method, Mr. Wiley points out 
certain sources of error which must be avoided ; such as 
the occlusion of silica. One method of evading this 
difiSculty is dissolving the original substance in sulphuric 
acid with a little nitric acid. Silica is not soluble 10 hot 
concentrated sulphuric acid. Error may, though rarely, 
arise from the presence of arsenic, and more ft'equently 
from the occlusion of magnesia and the volatilisation of 
phosphoric acid. 

Basic phosphoric slags have come into such extensive use 
that they have attraded the notice of sophisticators. Hence 
their analysis, and the detedion of adulterations (some 
of which have been adually patented I), becomes an im- 
portant question. It must be noticed that the substance 
known in Europe as Thomas slag is called in America 
•'odourless phosphate.*' 

For the determination of nitrogen in manures and their 
crude materials, the author gives the process of Dumas, 
available in all cases, but now rarely used except as a 
check; the soda- lime process of Varrentrapp and Will, 
very generally used until of late for the determination of 
nitrogen not in the nitric form ; and the Kjeldahl method, 
also not available for nitric nitrogenous bodies. The pro- 
cess of Wanklyn is pronounced to be of no pradical use 
whatever. 

For the detedion of potash in manurial matters, we 
find mention of a spedroscopic method. Potassium gives 
three faint and rather broad bands, two red bands, and 
one of a plum colour. If these bands are not deteded, 
we may at least conclude that the substance does not 
contain a ponderable quantity of potash. In addition to 
the ordinary platinum chloride method for the determina- 
tion of potash in its various modifications, we find the 
process for its estimation as perchlorate, which is pro- 
nounced quite as accurate as the platinum process, 
simpler, more expeditious, and cheaper. 

Mr. Wiley expresses the hope that deposits of potassiom 
salts may be discovered in the Uiut«d States. 

The fourth part of this excelligl )et^ treats of miscel* 
laneous fertilisers. The author cM.Acrs — in our opinion, 
rightly — that a soil good enough to grow crops will con* 
tain sufficient lime to furnish that ingredient of plant 



CllBlllCAL NbWB, I 

Nov. 15, 1895. > 



Chemical Notices jrom Foreign Sources. 



245 



food for many yean. The aAion of lime is certainly most 
favourable to those plants which are of value to men, 
whilst the plants which avoid lime, though often very 
beautiful, such as the heaths, azaleas, ftc. , are of little 
economical value. 

We are struck with a passage to the effed that lime is 
not capable of ading as a fungicide. ** As a rule fungi 
prefer acid readion in the substances in which they 
grow.'* With the morbific microbia this rule hardly 
applies. Most disease germs seem to prefer an alkaline 
medium. Thus the use of liquids containing a trace of 
sulphuric acid seems a safeguard against the infedion of 
Asiatic cholera. Yellow fever, on the contrary, prefers an 
acid habitat. 

Gypsum, it appears, has the strange synonym of '* land- 
plaster.** 

Under the name -" Stall manures,*' the author includes 
farmyard manures, night-soil, the excreta of poultry, ftc. 
Mr. Wiley very truly declares that such manures have a 
higher roanurial value than is deducible from the pro* 
portions of phosphorus, nitrogen, and potash which they 
contain (p. 3x1). This opinion we can confirm from our 
own observations, and we must regret that it has been 
ignored by many authorities in pronouncing on the value, 
i.g.t of sewage manures. 

Mr. Wiley's work must be regarded as a splendid con- 
tribution to the chemistry of agriculture. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NoTB^— All degrees of temperature are Centigrade anleM otherwise 
expressed. 

C^mpta Rmdus Hibdomadaires des Siatues, de VAcademit 
des Sciences, Vol. cxxi., No. 18, Oaober 28, Z895. 

Lord Kelvin, as a Foreign Associate of the Academy of 
Sciences, read the Address of the Royal Society of 
Liondon congratulating the Institute of France on its 
centenary, and further delivered a speech recognising 
France as his alma mattr of science. 

On the Chemical Equivalents.— M. Margfoy.— The 
aAual equivalents of chemistry are the prime numbers 
comprised in the natural series of whole numbers between 
I and 300. The author gives a table of his new equiva* 
lents in columns parallel with the present equivalents 
and the atomic weights. The equivalents of boron and 
sulphur he makes identical, as also those respedively of 
magnesium and glucinum, of chrome end psUadium, of 
tin and cobalt. That of nickel he makes 149, as against 
the equivalent 29*5 at present accepted. Gold and 
platinum he makes alike, as also tungsten and lanthanum, 
and iridium and osmium. The number of prime numbers 
which exist among the 300 whole numbers is 63. M. 
Margfoy adds that he has established the constitutive 
theory of substances founded on the unity of matter, he 
introduces into the consideration of the volumes the ele- 
ment of porosity, and thus succeeds in combatting the 
law of Dulong and Petit and the hypothesis of Avogadro. 
He puts forward the following law : — The specific heat 
multiplied by ihi dtnsity is equal to the porosity^ the 
porosity of hydrogen under the existing conditions of 
temperature and pressure being taken as unity. 

Thermo-chemical Researches out Lithium, Magne- 
sium, and Copper Cyanides. — Kaoul Varet.— The 
author's results are that the heat evolved from Li in solu- 
tion with gaseous cyanogen and water is +65*12 cal. ; 
that from magnesium under the same conditions is 
+ iia'0 cal. ; and that for copper i*29'8 cal. 

Glucinum Carbide. — Louin Henry. — If we ascribe to 
gluciuuin tiie atomic weight 903, and tu carbon that of 



ii*97> glucinum carbide must be represented by the for- 
mula CGI. Lebeau*s investigation gives us no reason for 
modifying the atomic weight and the valence generally 
attributed to glucinum. 

Analysis of Emerald. — P. Lebeau.— The author hat 
operated on the emerald of Limoges (Chanteloube, Haute 
Vienna). He gives the following results :-- 

Loss at a red heat . . . . 
Silica .. .. «. .. .. < 

Alumina 

Glucose (? should be glucina) . 

Ferric oxide 

Mn304 

Magnesia .. .. .« •• , 

Lime 

Phosphoric acid 

Alkalis — 

Titanic acid traces 



I. 


IL 


1-46 


z*4i 


6606 


6580 


z6i 


Z640 


1433 


1421 


I -a 


0-9 


055 


061 


o'i7 


0x4 


O'lX 


0*09 



100*11 



traces 



9967 



Oeterminatioo of Argoo.--Th. Schloesing, jon.-* 
This paper will be inserted in full. 

Syuthetic Formation of a New Ketonic Acid.— -£• 
Burker. — The compound in question has been obtained 
by the adion of camphoric anhydride upon benaene in 
presence of aluminium chloride. Its composition is 
C15H20OJ. It forms white crystals of a nacreous lustre 
which melt at 135—137* and boil at 320^ at a pressure of 
760 m.m. They are almost insoluble in water, sparingly 
soluble in ligroine, but readily soluble in acetic acid, 
alcohol, ether, benaene, chloroform, and carbon disul- 
phide. The author has formed and examined its ammo- 
nium, barium, silver, copper, cobalt, nickel, ainc, and 
lead salts. He has also obtained iu etbylic and methylic 
ethers, its anhydride, amide, and hydraside. 

Liquefa^ion of Gelatin; its Saline Digeation. — 
A. Dastre and N. Floresco.—Gelatin is transformable 
into a kindred substance, gelatose or protogelatose, 
charaAerised by want of the property of forming a jelly 
and of being precipitated by a standard solution of sodium 
chloride. In cultures of liquefadive miciobia it is ob- 
served in the first moments that the gelatin is changed 
into gelatose. Gelatin loses the property of jellifying if 
left in contaa with an alkaline chloride or iodide. With 
the fluorides, the transformation is only partial. The 
change may be named saline digestion. 



Zeitsehrift fur Analytische ChtmU. 
Vol. xzxiv.. Part 2, 1895. 
Researches on the Amorphous Nitrogenous 
Organic Compounds present in Beer Worts. — H. 
Scbjerning. 

Determination of Sulphurous and Sulphuric Acids 
m the Produ^s of the Combustion of Coal-gas.^ 
Uno Collan.^The author hopes to have demonstrated 
that the sulphur of coal-gas, both in the luminous and in 
the non-luminous flames, is chiefly converted into dioxide. 

Demonstration of the Blood-spots in Judicial In- 
vestigations.-^M. Gantter.— (See voJ. Ixxi., p. 238). 

Improvements in Glass Cocks.-- H. Wolpert.— 
This paper requires the nine accompanying figures. 

Retardation of Ebullition, and on the Ejection of 
Liquids. — H. Wolpert. 

New Burner for Sodium Light.— Richard Pribram. 
Simple Apparatus for Extraction. — Richard 
Pribram. 

Apparatus for Measuring off Small Quantities of 
Mercury in the Kjeldahl Nitrogen Process.— Paul 
Liechtli. — These three above papers cannot be intelligibly 
reproduced witnout the accompanying figures. 



246 



Chemical Notices from Foreign Sources. 



t CflBMICAL NSWt, 

\ Kw. 15, 1895* 



Detennloation of Antimony as Antimonic 
Antimoniate. — Otto Brunek. — Already inserted. 

Examination of Butter.— Carl Th. Mdrner.^The 
author finds the baryta number for twenty samples of 
fresh butter from Central and Southern Sweden on the 
average 200*7, <•'•> ^ ^i^^^^ lower than the values obtained 
by Kdnig and Hart. 

Introdu(5tion to Microcbemical Analysis. — H. 
Behrens. — This work is noticed in a brief but highly 
laudatory manner. 

Use of the Eledric Current as a Source of Heat. 
— A conspeAus of the methods devised by Saladin {Soe, 
Chim. di Paris), Ducretet and Lejeune {Ibidem)^ H. 
Moissan, Jules VioUe, and Lagrange, and Hohe (CompUs 
Rindus), 

Sources of Current, Resistance, and General 
Arrangements for BleArolysis.— A compilation in- 
cluding notices of a new dynamo for metallurgical labora- 
tories and ledure rooms, by W. Borchers (Comptes 
Rindus). — As the most convenient source of eledricity for 
chemical laboratories Karl Elbs {Chemikir Zeitung) recom- 
mends accumulators which may be readily charged by a 
Giilcher thermo battery of 66 elements. Felix Oettel 
{Chimikif Ziitung) shows that in diredlions for the eledro- 
deposition of metals it is necessary to specify the strength 
of the current per unit of surface ; as such unit he seleAs 
the square decimetre. Communications follow by J. S. 
Stillwell and Prof. P. T. Austen on the use of eledric 
lamps in eledrolysis. The authors use glow-lamps as 
resistances, which, as the Editorii point out, is no novelty. 
The contents of RiJdorff*s paper are purely polemical. 

Use of Sound Vibrations in the Analysis of 
Gaseous Mixtures. — E. Hardy. — From the Comptes 
Rendus* 

Apparatus for Purifying Oxygen and Air in Ele- 
mentary Analysis. — Hugo Schiff —A description of the 
apparatus would require the two accompanying figures. 

New Urometer.— Th. Lohnstein (^4//. Med. Central- 
Ziitung), — A special form of hydrometer. 

Some small Laboratory Apparatus.— Andr6 Bidet. — 
These appliances cannot be satisfadorily described with- 
out the accompanying figures. 

Motor for Laboratory Purposes.— Ewald Saor.— 
This apparatus is an application of Henrici*s hot-air 
motor, and cannot be described without the illustration 
here given. 

New Cock for Vacuum Exsiccators. — O. Ernst. 

Determination of Carbon in Iron. — A critical com- 
pilation of known methods. 

Distind\ion between a- and iB-Naphthols.— Aymonier 
{Repert. Pharm, and Zeit. des Allgem. Oesterr. Apotheker 
Vereins) uses a solution of x grm. of potassium dichro- 
mate and x grm. nitric acid in xoo c.c. of distilled water. 
If a few drops of Wiis solution are added to an aqueous 
or dilute alcoholic solution of the naphthols there appears 
a black precipitate in the absence of a-naphthol. 



MEETINGS FOR^THE WEEK. 

Wbonisoat, 20tb.— Society of Arts, 8. Open'ng Addreti of the 
142nd Session, by Major- General Sir John 
Donnelly, K.C.B., Chairman of the Council. 
Thursday, 2iit.~Cbenitc«l, 8. •• The Evolution of Carbon Mon- 
oxide by Alkaline Pyrogalloi Solutions during 
Absorption of Oxygen,** by Prof. Clowes. " The 
Composition of the Limiting Explosive Mix- 
tures of various Combustible Gases with Air." 
'* Barium Butyrate, and the Estimation of 
Butyric Acid," by W. H. Willcox. And other 
papers. 
FtiDAY, aand.— Physical, 5. An Exhibition of Photographs of 
SpeAra, by G. Johnstone Stoney. ** A DiteA- 
reading Platinum Thermometer.*' by R. Appleyard. 
** Historical Note on Reaiatance and its Change 
with Temperatare," by R. Apple>ard. 



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CRBMICALNlWt,) 
SOV. 32, 1895. t 



Determination 0/ Argon. 



247 



THE CHEMICAL NEWS 



Vol. LXXII., No. 1878. 



ON ARGON. 
By R. NASINI. 

Ths aathor it of opinion that the mooatomic cbarader of 
argon, at deduced from the kinetic theory of gatea, can- 
not yet be regarded at irrefragably ettmblithed. If the 
kinetic theory of gatet allowt ut to prediA for monatomic 
gateoas molecnlee with great probability a valoe for k 
approximating to 1-67 (k being the relation of the specific 
molecular heat at a conttant pretture to the ipecific heat 
at a conttant pretture), according to the author, the 
reciprocal relation is not to be regarded at necettary ; 
that is, it cannot be generally concluded that k has the 
same value for every monatomic molecule. It is sufficient 
to assume that the energy of the rotatory movements 
represenu a very small and negligible part of the progres- 
sive movements, and that no— or only very slight — move- 
ments take place between the several atoms within the 
molecule in order to justify the assumption that also 
in polyatomic gaseous molecules the value 1*67, or an 
approximate number, can be obtained for k. If, further, 
the value 40 were absolutely demonstrated as the atomic 
weight of argon, this element would find no place in the 
periodic system, and the system itself would be subverted ; 
as would alto be the case if a value were found for tel- 
lurium higher than that for iodine. 

If we assume the value ao for argon, it may find a place 
in the 8th group between fluorine and sodium. This 
place in the periodic system seems very suitable, especi- 
ally as the transition from fluorine to sodium is not at all 
mediated. Ii; according to the conjeAure of the discoverers, 
argon consists of two elemenu with the atomic weights 
37 and 82, we could no longer admit the eighth group in 
the sense now admitted, ft would then be necessary to 
assume the existence of a new element after each halogen, 
ao that, i,g,9 an element of the atomic weight ao would 
follew after fluorine, and another between iodine and 
csBsium. These elements would then form an eighth 
group and conclude the period, whilst the pretent eighth 
group must form a new group— the ninth. 

In the present position of the question we must abandon 
either the conclusions universally deduced from the kinetic 
theory of gases or the periodic system. 

As long as more cogent evidences cannot be brought 
forward, the author does not believe that 40 represents 
the true atomic weight of argon.— Goss. Chim. Ualiana 
and Ckimktf Ziitung. 



ON THE DETERMINATION OP ARGON. 
By TH. SCHLOSSING, Jan. 

The procedure for the determination of argon described 
in my last paper {Comftss Rtndus, cxxi.. No. z6 ; Chbbi. 
News, Ixxil., p. azi) yields, according to the verifications 
submitted, results too low by an average of 0*6 per cent. 
This error is not great ; we know its direAion and we 
may accept it. I have sought to ascertain its cause, not 
so much in order to arrive at a closer approximation, as 
in the hope of deteAing some readion which is the origin 
of the slight loss observed. 

In the apparatus which I have described, argon is 
brought in contad at a red heat with magnesium, copper, 
cupric oxide, steel, porcelain, and asbestos. Can it be 
some one of these substances which has a slight adion 



upon argon ? In order to answer this question I have 
performed a methodical series of experiments, causing 
volumes of argon, accurately measured, to circulate 
in the apparatus for a certain time, then extraaing them, 
and re-measuring them after having been submitted to 
the ipark in presence of oxygen and potassa, the condi- 
tions of the experiment having been successively modi- 
fied, so that we may perceive the influence of each. 

Thete experiments, which it would be too tedious to 
describe in detail, have shown that the total of the some- 
what complex manipulations of a determination involves 
a small lots of about o*a5 per cent of argon, when the 
magnetium tube hat not been heated ; that the total loss 
is between 0*5 and i per cent if the tube is heated as for an 
ordinary operation ; that it increases slightly with the 
duration of the experiment, and also with the tension of 
the argon in the apparatus ; and that it does not appear 
distindly due either to the steel, the porcelain, the 
asbestos, the copper, or the cupric oxide. It followed 
already from the experiments of Lord Rayleigh and Prot 
Ramsay that argon is not appreciably absorbed by copper 
or by cupric oxide, and here the fad is verified with all 
needful precision. 

Among the experiments which I mention, those in 
which the tube of steel or of porcelain is heated, as in 
the majority of the determinations, for an entire hour 
have given the following losses : — 0*70, 1*13, 0*66, 0*69, 
0*63, 0*43* 0*51, or a mean of 0*68 per cent of the argon. 
This figure, o'68 per cent, agrees well with that (o*6a) of 
the experiments of verification referred to above. In fine, 
we may admit that for a series of determinations the 
mean error is approximately 0*7 per cent. 

I have applied the procedure in question to the deter- 
mination of argon in normal air. It has given the fol- 
lowing results: — 

Normal Air tak$n in Paris at about zo wutrts 
abovi thi Ground. 

Argon 



Sept. as 
.. a6 

oa. z 

•f 4 



In 100 vols, sir 
In 100 volt, of cootsinioc 79*04 
aunotpheric nitrogen. ofnitrogoa. 

ZZ85 0*9369 

z«z83 0-9349 

Z'z85 0*9367 

z*z8o 0*9335 

z«z85 0*9363 



Mean. 



z*i84 



0*935 



In zoo vols, of 
stmotpheric nitrocta. In 100 vols, of sir. 
Air taken in Normandy, on 



a hill of 305 metrei high 


I'zSa 


o'9343 


Air taken at 300 metres 






high on the Eifiel Tower 


i*z8o 


0*9338 


Air taken in an iron mine 


i*z83 


o'9354 



Mean. 



z*z8a 



0-934 



The slight respeaive diflferences shown by these results 
are of the rank of experimental errors. They do not 
necessarily correspond with real variations of the amount 
of argon in the air. If such variations occur they are 
probably very slight. Thus it roust be laid down for 
argon as for the two most abundant elements of the atmo- 
sphere, oxygen and nitrogen, its proportion varies only to 
a degree scarcely perceptible on analysis. The constant 
composition of our atmosphere is explained, as it is 
known by the incessant stirring to which it is submitted. 
As regards argon, its chemical inadivity, if confirmed, 
would be another reason why it should not vary. 

If we make the corredion of 0*7 per cent in addition to 
the above means as regards normal air they become i*Z9a 
and o*94Z. We may easily calculate the difference with 
this figure of z*z9 per cent (the first cause of the discovery^ 



248 



Chemical Researches and Spectroscopic Studies. 



i iJBBiiiau. !>{•«•, 



Nov. ast 1895. 



of argon) between the weight per litre of atmoBpheric 
nitrogen and that of chemical nitrogen^a difference 
which Lord Ray lei gh and Professor Ramsay determined 
diredly by measurements of great precision, and found 
equal to 1*2572 grm. — x'2505 grm., or 0*0067 grm. If, in 
f|ta, Dx, Da, and D3 are respedivelv the weights per litre 
Qf argon, of chemical nitrogen, and of atmospheric nitro- 
gen we shonld have — 

o'ozig Dx+(x -0*0119) Da'Dj, 
whence— 

D3 - Da - o'oi 19 (Di - Da). 

'■ Now, the experiments of Rayleigh and Ramsay show 
ns Dz and Dz* They have given Da "Z '2505 grm., and 
for the density of argon with reference to hydrogen 19*9, 
or for the weight per litre 19*9x0*0896 grm., or 0*783 



We have, therefore, with a sufficient precision 
Di — Daao*5325 grm. and Da — Da""0'oo63 grm. This 
yalue of 0*0063 grm. of the difference in question ou^ht to 
be, ^n consequence of the procedure by which it is oh- 
tmined, a closer approximation than the foregoing 0*0067 
grm. 

^ Here follow some results referring to gases extraAed 
from agricultural toils. 

Argon for 100 volt. 

of nitrogen 
accompftnied with 



Gas taken at a depth of 0*20 metre in the 

soil of a pine forest 1*170 

Gas taken at a depth of 0*40 in a ploughed 

' soil Z'x69 

Gas taken at a depth of 040 in a ploughed 

soil 1*155 

Gas taken at a depth of 0*40 in the »oil of 
a garden 1*118 

The mean of these figures is lower than that corre- 
sponding to normal air, which depends in part on the sol- 
vent a^ion of water (argon, according to Rayleigh and 
Ramsay, about 2i times more soluble in water than is 
nitrogen), always supposing that the rain reaches the soil 
before it has uken up from the air all the proportion of 
argon which it can dissolve. — Comptes Hindus, cxxi., p. 
604. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By J BAN SBRVAIS STAS. 

(Continued from p. 241). 

D. Oh thi Holders used to hold Compounds in an Electric 
spark or Discharge. — ^^I'o hold the compounds to be vola- 
tilised I used platinum or iridium ballsj m.m. in diameter, 
at the end of a platinum wire i m.m. in diameter, or, 
better still, small cones of purified carbon fixed to a 
platinum wire. The platinum or iridium balls, and the 
small * carbon cones, 'were completely covered with the 
compounds in the form of anhydridis or hydrates, or 
sometimes merely soaked in a saturated solution of the 
compound to be volatilised. 

I made different arrangements according as I passed the 
spark or current in the surrounding air, or in purifiid air, 
or in pure hydrogen. 

When I worked in the outer air I clamped, and held bv 
acrew clips, the platinum wires, ending m balls or small 
carbon cooes covered with the compounds, between two 
separate and insulated metal rings. The two metal rings 
were attached to a varnished glass stem by means of 
insulated supports. The glats stem was mounted on a 
metal stand ; it could be raised or lowered by means of a 
rack with which the stand was furnished. Thanks to 
these arrangements, one could raise to any height required 
lhe two rings attached to the stem^ adjust the, distance 



between the balls or saturated carbon cones, and pasa 
the spark or discharge between them. 

Having arranged the apparatus in front of, and aa near 
as possible to, the slit of the speAroscope, and having 
guarded it against spattering by interposing a thin sheet 
of mica, one can at will let through the slit of the spedr(>« 
scope the rays from either the middle of the spark or from 
either of its ends. 

When the platinum balls or the carbon cones were 
completely covered by the compounds to be volatilised, 
spedrum analysis of a* spark, or even a discharge, showed 
no lines due to platinum or carbon. 

When working in purified air, or, better still, in pnrg 
hydrogen, I used the same platinum wire holders, ending 
in balls of this metal or of iridium, or carbon conea» 
completely covered with the compounds to be volatilised 
in the spark or discharge ; but in this case I arranged the 
platinum wires by means of well^wasbed corks in a glaaa 
tube open at both ends, from 2 to 3 cm. diameter b^ zo 
cm. in length. 

At a distance of a cm. from each end was fixed a small 
glass tube, furnished with a cock meant to admit and 
maintain a ctirrent of purified air or pure hydrogen whilat 
the sparks or eledric discharges were passing. 

Whatever care might be used in fitting; the apparatna, 
it was impossible to prevent the outer air from diffusing 
into the gas in the tubOi especially when this gas was hyw 
drogen. For this reason it was necessary to maintain the 
current during the experiment, and at least to eompUUfy 
cover the corks fitted to the tube, as well as a part of the 
tube itself, with a layer of melted shellac or wax« 

When working with a spark in the open air 1 sometimee 
did and sometimes did not see atmospheric lines. In a 
note* I give the reason of the appearance and disappear* 
ance of atmospheric linea. 

SpeArum analysis of the discharge in air enabled me to 
deted the constant presence of atmospheric lines superposed 
on the lines of the compound volatilised in the discharge. 
This constant presence makes observations of a discharge 
painful and uncertain. 

Passing a short spark in hydrogen showed only the red 
hydrogen line with the spedrum of the volatilised com* 
pound, whilst a discharge in hydrogen constantly shows 
the red and bluish green C and F linea superposed on the 
spedrum of the volatilised compound, the F line appear* 
ing as a band shaded on both sides. However intenae 
the discharge might be, I could not deted the other hy» 
drogen lines. 

To put a saline solution into an eledric spark or dis- 
charge, I took a clear glass tube, open at both ends, zo 
cm. long by 3 cm. diameter, fitted with glass taps in the 
sides, towards the top and bottom^ to admit a current of 
pure air or hydrogen. In the lower end of the tube I 
fitted a plug of pure rubber, very slightly tapered, pierced 
by a platinum rod 3 m.m. diameter, terminating above in 
a tripod of the same metal, and having a hole below to 
make contad with the positive eledrode. 

I placed on the tripod a platinum dish slightly smaller 
than the diameter of the tube, containing a hollowed cone 
of this metal with a capillary hole through it* the top of 
which was about 2 m.m. above the top of the dish. I 
filled this dish with the saline solution to be put in a 
spark or discharge which flashed from the liquid covering 
the top of the cone 

The upper end of the tube was fitted with a slightly 
tapered plug of pure rubber, pierced by a pure platinnm 
rod 3 m.m. diameter, terminating below in a point, and 
with a hole above to make contad with the negative 
eledrode. 

Before receiving the saline solution to be put into the 
eledric spark or discharge, the dish as well as the plati- 
num cone held in it were washed with very dilute hydro* 
chloric acid, then with pure water, and finally made 
white-hot. 

* Chsmical Nsws, vol. Uiii., p. 326 (and footootc). 



• ClIsiiiCAt Hurt. I 

Nov. 22, 1895. t 



Chemical Researches and Spectroscopic Studies. 



24^ 



The terminal point of the platinum rod, before being 
adjaated vertically above, and from 2 to 3 m.m. from the 
top of the platinom cone, wai treated in the lame way as 
the dish. 

Thanks to the pare rubber plug, this apparatus preserved 
perfedly the pure air and hydrogen contained in it. 
When working in air, the liquid, being in contaa with 
platinum only, yielded, on spedrum analysis of the spsrk 
aaturated with the liquid which rose by capillarity to the 
top of the cone, the spedrum proper to the compound, to 
which nevertheless was often added the red hydrogen line. 
SpeArum analysis of a spark showed the same spedrum, 
to which was added some atmospheric lines. When 
passing a spark or discharge in hydrogen, one saw the 
spedrum of the saline liquid, to which was added either 
the red hydrogen line or the reddish and the bluish green, 
or more frequently greenish blue, hydrogen lines. 

When one substitutes, as is generally done, for the ap- 
paratus arranged as described above, a glass tube which 
18 itself used to hold the saline solution, and when one 
prolongs for some time the sparks, and, better still, the 
discharge, one notices that the spedrum seen shows the 
sodium D line and some calcium lines, even though the 
saline solution in the tube contains mithtr sodium nor ccU- 
eium. As a matter of fad, in the apparatus utuallv used, 
the calcium and sodium are obtained from the g^ass by 
the attack on the tubes near the platinum wires, and 
especially on the small glass cone, which admits the 
wire used for the positive eledrode. 

When using apparatus of which all parts to be put in 
contad with a saline solution are made of platinum, the 
method of analysing a spark or discharge saturated with 
a saline solution shows an advantage over the analysis 
of a spark or discharge passed between balls or cones 
coated with solid compounds, whether anhydrous or by- 
drated. In fad, in the former apparatus, one can make 
the compounds with which one wishes to saturate the 
apark or discharge^ in a close tube filled with air or hydro- 
gen. Relying on this possibility I tried to ascertain 
whether one could get, by means of calcium oxide, hydro- 
chloric acid, or nitric acid, /r## frofk sodium t some 
dissolved chloride or nitrate of calcium, which, when in- 
troduced into a spark or discharge, would not show the 
sodium line on spedrum analysis, a thing I could not 
accomplish with compounds made in the open air. I 
showed this possibility, and I satisfied myself absoluttfy 
that the presence of sodium in a chloride or nitrate pre- 
pared in the open air is due to the sodium contained in 
the air. In the notes on the flame and eledric spedra of 
chloride and nitrate of calcium I describe my observations 
on this point. 

The method of experimenting described above has a 
fault which I ought to mention. It is, in many instances, 
a fad that spedrum analysis of a spark or discharge, in a 
strong or weak, neuUal or acid, solution of any of the 
metallic compounds, fails to show always a spedrum con- 
taining all th$ charaetiristic lin$s of thiu compounds. 

In many cases the spedrum is incomplete. Thus, 
whatever spedroscope be used, spedrum analysis of a 
spark through a sodium salt only shows on$'third of 
the lines seen in the eledric spedrum of sodium salts. 

Experience has taught me that the greater or less vola 
tility of the compounds is not the reason of the appear- 
ance of complete or incomplete spedra ; for a spark, 
which only shows one-third of the lines in the eledric 
spedrum of sodium, shows a barium spedrum identical 
with that of an eledric arc saturated with barium. 

According to my experience and the checks to which I 
have submitted my researches, in collaboration with M. 
Depaire, this method of spedroscopic research, whatever 
services it may have yielded, is not competent to give a 
decisive indication as to the frestnce or ahsinc$ of a given 
body in a compound submitted to analysis. 

£. On thi Holdifs used to Volatilist Difftnni Bodi$s in 
an BUcirie Arc—To volatilise the different bodies in 
which I was carrying on my investigations in an eledric 



arc, I first aded in the same way as when placin|| thd 
same bodies in an eledric spark or discharge, — that is to 
say, I used rods of pure carbon, of considerable length 
and diameter, with their extreme ends covered with these 
bodies, just as I have already described in notes on my 
studies of different metals and metallic compounds. But 
I soon learnt the weak points, or I might even say the 
errors of principle, which are associated with this method 
of experimenting. The voltaic current being established 
by connedins the poles and the volatilising of the com- 
pounds which covered them, the poles were brought at 
once to the brightest incandescence. This incandescence 
was less or greater according as the eledrodes were rn 
contad or were separated to make an eledric arc. The 
sum of the light from the poles and from the eledric arc 
proper are said to form thi iUetric ligj^t. 

But in his researches ** On the Temperature of the 
Carbon Poles at the Instant they make the Eledric Light, 
and on the Temperature of the Elednc Arc,"* Rossetti 
found, at the end of the positive pole, a maximum tem- 
perature of 3900°, at the end of the ntgativi pole a 
temperature of about 3X5o^ and in the arc itself a 
temperature of 4800^ whatever might be the diameter 
of the arc and the intensity of the current which pro- 
duced it. 

Besides, when looking closely into an arc which passes 
between two poles, one sees at once that its strudure is 
not simple. At the beginning— that is to say, in the crater 
whence the arc springs — it emits sky blue rays. The 
arc proper is of a purplish blue colour. This difference 
of colour between the arc at its origin and the body of it 
shows it to be surrounded by a pink* red gaseous envelope, 
of which the colour deepens gradually from the outside of 
the arc towards the skf'blue part. 

The arc, at its origin, appears to me to consist of car- 
bon vapour, whilst the centre is composed of the same 
current of carbon vapour, but partially oxidised by its 
contad with the air which flows continually round the 
arc. The colour of the envelope of the arc closely re- 
sembles the tint which the inner cone of an oxyhydrogeo 
blowpipe assumes when one puts a filament of pure car- 
bon into it. Since an oxyhydrogen blowpipe supplies a 
considerable excess of hydrogen mingled with oxygen, 
the carbon bums in it with the greatest brilliancy, and the 
flame produced thus is either red or pink, according as 
one looks at it near the point where the filament is held 
in the blowpipe, or at a part distant from that point. I 
have seen the same pink-red colour when distilling silver 
contained in a pure carbon retort in an oxyhydrogen or 
oxy-coal-gas blowpipe. The flame which issues from the 
retort is pink-red, in spite of the large quantity of silver 
vapour it contains. 

The temperature of the gaseous envelope surrounding 
the arc is excessive. It greatly exceeds the fusing-point 
of pure platinum, which is that of the inner cone of an 
oxyhydrogen flame. In fad, pure iridium attached to a 
carbon filament melts rapidly when put into it. 

Pure iridium which one drops into the crater of an arc 
two and a half cm. long, with a carbon spatula, is vola- 
tilised at once, and in a very short time covers the 
negative pole with small drops of melted iridium. 

The poles emit heat rays ; the arc emits both electric 
and heat rays ; as determined in my researches on the 
heat and eledric spedra of sodium in an eledric arc. 
When one projeds into the slit of a spedroscope, a beam 
of parallel rays from the poles and the arc at once, 
and saturates the arc with a volatilised compound which 
has a different heat and eledric spedrum, the image has 
the charaderistic lines of both spedra. 

It follows from these fads that, when using an eledric 
arc to study the spedrum of a body, one ought to throw 
parallel rays coming from the poles, and parallel rays 
coming from the arc, separately on the slit of the spedro- 

• AnnaU* de Chtmie et de Phytique, Fifth Series, vol. xvfii.. 9.476 
Paris, 1879. 



250 



Vapour -tensions of Mixtures of Volatile Liquids. 



f CBBMCAL VlWBy 



Mot. 22, i8^ 



scope, as I have taken care to do since I have nnderstood 
the complexity of the ele^ric light. 

(To be continned). 



ON 



THE VAPOUR.TENSIONS OF MIXTURES 
OF VOLATILE LIQUIDS.* 
By C E. LINBBAROBR. 

(Contintied from p. 239). 



VapouT'tSHMums ofMixtuns of Aettie Acid with Binsins 
and with Tolutne. 

Two series of determinations were carried out on the 
mixtures of benzene and acetic acid, one at 35^ and one 
at 20% but one, however, for the mixtures of toluene and 
acetic acid, at 35^ In order to apply to the experimental 
reiults of the work oar mode of calculation of the vapour- 
tenstoni, it is necessary to know the molecular mass of 
gaseous acetic acid at the above two temperatures. 

* Abridced from the Joutnal of the Americnn Chemicat Society, 
vol. svii., No. 8, Aofiist, 1895. 



Now acetic acid even in the vaponrons condition is made 
up in part of polymerised molecules, so that it is not 
legitimate to set its molecular mass equal to that corre- 
sponding to the formula C2H40a. What the adual mole- 
cular mass of the gaseous acid at 35° and 20° is can be 
easily calculated by the aid of the vapour-density deter* 
minations of Bineau ('* Recherches sur les Relations des 
Densit6s des Vapeur avec les Eqnivalenu Chimiqoes;" 
Ann, Chim. Phys., xviii., 226, 1846), which are the more 
applicable to the case in band as his vapour-density 
measurements were made under the same conditions as 
my vapour-tension determinations ; that is to say, Bineau 
measured the amount of acetic acid that diffused into a 
definite volume of air at a fixed temperature. The mole* 
cular mass of acetic acid as deduced from Bineaa*s obser- 
vations is Z04 for 35° and xxo for 20^ It may be worth 
while to remark that an error of five in the molecular mass 
will not entail an error of z millimetre in the vapour- 
tension ; we may with all confidence then adopt the above 
molecular masses of acetic acid in state of vapour as quite 
accurate. 

The necessary data of the experiments are given in 
Tables X. to XII.; the superscription to each vertical 
column renders any explanation of them here superfluous. 



Table X,^Vapour 'Tensions of Mixiuns of Benzene and Acetic Acid at 35° 

Vapour-tension of Benzene at 35^ is Z46 m.m. of Mercury. 

Vapour- tension of Acetic Acid at 35° is 26*5 m.m. of Mercury. 



P.c.ofC.lI«0« P.cofC.H^O. 
in liqoid mUt. in gaMout mut. 



644 
1517 
37x0 
43*99 
4986 

5324 
5465 
5660 

7387 
80*00 



P.c.ofC,H«0. 
in liquid mist. 



5324 
80*00 
97*28 



2*45 

474 
8*25 

IX*02 
12*26 

13-33 
13-82 
14*62 
20'l8 
26*91 



Orms. CaH«Oft 
in vapour. 

0*0461 
0*0834 
0*0700 
0*0867 
0*0931 
0*0969 
0*0990 
0*1063 
0*1x56 
0-I35X 



Onns. C«H, 


Tension of 


Tension of 


Volume of 




Internal 


in vapour. 


CiH«0, in m.m. 


CfH, in m.m. 


air in mjn. 


in m.m. 


prea. mji 


X-3759 


3*5 


X40-0 


X955 


758 


X4 


1*3580 


6*4 


129*2 


X958 


758 


X5 


1*5840 


10*5 


1x7*0 


X020 


767 


16 


05243 


13-2 


xo6-5 


10x9 


766 


x6 


0*4849 


14*0 


X03*i 


1020 


766 


X7 


0-473X 


14*9 


97*6 


1020 


766 


X7 


0*4630 


X5-3 


973 


1020 


766 


X7 


0*4677 


x6*4 


96*0 


X020 


766 


X7 


0*4585 


18*4 


727 


ZOI9 


766 


16 


o*275X 


22*3 


593 


X020 


766 


X7 



Tablb XI. — Vapouf'Tensions of Mixtures of Benzene and Acetic Acid at 20^. 

Vapour-tension of Benzene at 20° is 75*6 m.m. of Mercury. 

Vapour-tension of Acetic Acid at 20^ is 11*7 m.m. of Mercury. 

P.C. ofC,H«OB Ormt. C,H«0, Orma. Call, Tension of Tension of Volume of Barometer Internal 
m f aaeobs mixt. in vapour. in vapour. CsH«0, in m.m. CgH, in m.m. air in c.c. in m.m. prea. m. 

iz*99 0*0440 0*2291 6*6 487 10x8 760 x6 

21*97 0*0576 0*2100 9*1 33*o 1018 760 z6 

64*66 0*0674 0*0276 11*4 6*2 ioz8 760 x6 



Tablb XII. — Vapour-Tensions of Mixtures of Toluene and Acetic Acid at 35^ 

Vapour-tension of Toluene at 35'' is 47*2 m.m. of Mercury. 

Vapour- tension of Acetic Acid at 35° is 26*5 m.m. of Mercury. 



P.c.ofC«H«0, P.c.ofC4H40, 
in liquid mixt. in gaseous mixt. 
32*66 



49-00 
60*88 
83-37 



3r9X 
56*36 



Orms. C,tI«Os Orms. CfHa Tension of Tension of Volume of 

in vapour. in vapour. C,H«Otin m.m. CrH, in m m. air in cc. 

0*09x1 o*x66i X5*o 31*8 X020 

0-X025 0*1485 X7*4 28*5 X020 

0*1252 0*0858 22*2 i6'7 X020 



Barometer 
in m.m. 



760 
760 
760 



Internal 

X8 
X8 
x8 



Tablb XIII. — Partial Pressures of Benxene^ Acctie Acid, and Toluene. 

Per cent of C,H«0, Partial preaaure of Partial preasure of Partial pressure of Partial pressure of Partial preaaore of 

in liquid mixture. C«Ha at 33^ in m.m. CtH«0, at 33° in m.m. C, H, at 35** in m.m. CaH, at 20*" in m m. CftH«Oa at ao* in m.8K 

xo X38*4 2*8 44*5 71-4 x*2 

20 X30*9 5*6 41*6 67*5 2*3 

30 122*2 8*2 38*6 63*1 3-5 

40 XX2*6 ii*i 35*o 582 48 

50 io2*4 13*6 3X*9 53*2 6*0 

60 90*7 i6*2 27*8 47* X 7'2 

70 76*7 X9*i 23*x 40*1 8*4 

80 59*x 2X*7 18*4 3X*x 9^6 

90 35*x 24*2 xx*i 18*5 xo*7 



CflSMICAL ftlWt, I 

4pY. as, 189s. f 



Quantitative Determination of Perchlorates. 



251 



From these data curvet were constraded on a large 
■cale with percentage! of composition as abscissae and 
vapour-tensions as ordinates (i inch on the axis of ab- 
■cisf se corresponded to 5 per cent ; z inch on axis of ordi- 
nates to 10 m.m. of pressure) ; these proved to be perfedly 
tegular, and passed diredly through most of the points. 

The points for acetic acid either fell upon or very close 
to the straight line conoeAing the left hand origin of the 
co-ordinate system with the point on the right hand axis 
of ordinates corresponding to the value of the vapour- 
tension of pure acetic acid at the temperature in question, 
vix., a6'5 for 35°, and 1x7 for 20°, the acetic acid vapour- 
tension curve is simply a straight line, then, when the 
composition is expressed in percentages. An interesting 
conclusion to be drawn from this fad is that the partial 
tension of acetic acid is the same, be it mixed with ben- 
xene or with toluene ; the specific influence of the diluting 
liquid seems to be extremely slight, if, indeed, there is any 
at alL This circumstance also indicates that the mole- 
cular condition of the acid is the same when it is dissolved 
in either of the hydrocarbons so as to form solutions of 
^e same strength ; this insight into the molecular struc- 
ture of acetic acid enables us to determine by a little cal- 
culation its molecular mass not only in the dissolved but 
also in the pure state. In the following seAion will be 
■ec forth the modus operandi. 

From the curves drawn as just described above, the 
partial pressures of the various constituents of the mix- 
tores were taken for concentrations corresponding to zo, 
20, 30, .... 90 per cent of acetic acid ; the data thus 
obtained are given in Table XIII. 

(To be oostintied) 



THE QUANTITATIVE DETERMINATION OF 

PERCHLORATES.* 

By D. ALBERT KRBIDER. 

(Contioued from p. a4a). 

The results obtained by substituting (a) cadmium iodide 
and (6) anhydrous xinc chloride for the double chloride 
of aluminum and sodium are recorded in Table VI. In 
(27), (28) and (29) cadmium iodide was used, and the 
iodine obtained by treating the cooled mass with dilute 
sulphuric acid (i : 6) and potassium iodide for the reduc* 
tion of cadmium oxide in each case added to that of the 
receivers. In (30) and (31) zinc chloride was employed, 
but no additional iodine was obtained by treatment with 
sulphuric acid and potassium iodide. 



(27) 

(28) 
(29) 



KCIO^ 
Orm. 
O'lOOO 
O'lOOO 
O'lOOO 
0*1000 
01653 



Table VI. 
KC10« found. 
Orm. 
00745 
0*0693 
0*0679 
0*0245 
0*1156 



Error. 

Grm. 
0*0255- 
0*0307 - 
0*0321 - 
0-0755- 
00497- 



In (31) manganous chloride was mixed with the zinc 
chloride in the proportion of a : i, in the hope of 
strengthening the reducing adion. The black colour of 
the fission revealed the formation of manganese dioxide, 
the equivalent of which in iodine was obtained by dis- 
solving the cooled mass in water, adding dilute sulphuric 
acid and a Imown amount of ammonium oxalate, titrating 
the residual oxalate with permanganate solution, and cal- 
culating the difference into iodine, which was added to 
that obtained by titrating the contents of the receivers. 
This addition of manganous chloride to the fusion of the 
double chloride of aluminum and sodium was forestalled 



* CoBtribvtiont from the Kent Chemical Laboratory of Yale Col- 
lece. FrosB the Amtrican Journal oj Science, vol. I., OAober, 1895. 



by the necessity of subsequent solution of the fused 
mass, which contained an impurity in the form of ferric 
chloride, which of course in the presence of hydriodic 
acid would be reduced with evolution of iodine. 

It was evident from all these results, as well as those 
obtained by use of other salts not necessary here to 
record, that fusion with salts of the halogens would not 
suffice for the complete redudion of perchlorates, or at 
least would not quantitatively register the result in the 
halogen liberated. The well-known readion of the 
oxidation of chromic oxide by fusion with alkaline car- 
bonates was also applied, A combustion- tube was used 
for the fusion, sealed at one end, and, after the insertioii 
of chromic oxide with a mixture of sodium and potassium 
carbonate, restrided at the other end so as to admit a 
small tube by which carbon dioxide could be entered to 
expel all air. A blank determination gave no chromate. 
When 0*1 grm. potassium perchlorate was mixed with an 
excess of chromic oxide and alkaline carbonate, and care* 
fully fused from the top, and kept in a state of fusion 
throughout its length in an atmosphere of carbon dioxide, 
the fusion subsequently dissolved in water, and the 
chromic oxide removed by filtration, an amount of 
chromate was obtained on titration equivalent to only 
0*0347 grm. of potassium perchlorate. 

Powerful as were the various reducing agents employed 
for the decomposition of perchlorates, they were td\ suc- 
cessfully resisted, even at the highest permissible tem- 
peratures ; and if anything is proved by the results of the 
experiments above recorded, it is that perchloric acid is, 
in combination, one of the most powerful and stable acids 
known. Certainly nothing short of high temperatures 
is capable of overcoming the remarkable affinity by which 
the oxygen of this acid is held by its salts. At about 
400* C. the potassium salt fuses with evolution of oxygen, 
and as a last resort an attempt was made to have the oxy- 
gen thus obtained ad on hydriodic acid by intervention of 
nitric oxide. It was the application of this principle that 
led to the final method, which, both as to manipulation 
and results, leaves nothing to be desired. 

The method is essentially the collodion of the oxygen 
of the perchlorate ; its subsequent passage into an atmo- 
sphere of nitric oxide over a strong solution of hydriodic 
acid, and the titration of the iodine thus liberated with 
decinormal arsenic in alkaline solution. The apparatus 
employed consisted of a piece of combustion tubmg 10 or 
12 cm. in length, drawn out at one end to a narrow 
restridion of length sufficient to prevent the adion of the 
heat on the rubber tubing connediog it with a receiver 
filled with caustic potash. The tube must of course bo 
cleansed from all organic materials, and cannot be safely 
employed for more than three fusions. A platinum t>oat 
(porcelain fusing to the glass) served for the introduaion 
of the perchlorate to the combustion-tube, and, in order to 
bring about a gradual and quiet fusion, the perchlorate 
was covered with a small amount of an equal mixture of 
dry and pure sodium and potassium carbonates. CarboQ 
dioxide obtained from a Kipp generator, the acid and 
marble of which had been previously boiled to expel all 
traces of air, and to which a little cuprous chloride had 
been added to take up any oxygen which might be ab- 
sorbed from the top, was passed through a solution of 
iodine in potassium iodide to remove a trace of reducing 
agent which it was found to contain, and then washed 
with potassium iodide solution before being used. The 
larger end of the combustion-tube was closed with a per- 
forated rubber stopper by which it was attached to the 
carbon dioxide apparatus. Af^er all air had been expelled 
from the inclined tube by means of carbon dioxide, it was 
conneded bv a short glass capillary and vacuum tubing 
joints with the receiver, into which about 50 to xoo cm.* 
of gas was allowed to flow before the combustion was 
started, and thus, when only a small but inevitable bubble 
remained insoluble in the caustic potash, the complete 
removal of air was indicated. To prevent the caustic 
potash from drawing into the combustion' tube, a httk 



252 



Quantitative Determination oj Perchlorates. 



I CBxmcAL Niwt, 
I Nov. as, 189s. 



more carbon dioxide was entered, when the current was 
doted by a pinchcock on the side towards the generator, 
and heat gradually applied-^with perforated asbestos cards 
on either side to check its radiation to the rubber — and 
continued till the contents of the platinum boat was in a 

auiet state of fusion. By lowering one of the bulbs of 
^e caustic potash receiver^ the oxygen was evolved under 
slightly diminished pressure, and thus the chances of loss 
decreased. Then the tube was again inclined and care- 
fully annealed, while a current of carbon dioxide carried 
a]l of the oxygen into the receiver, which was then closed 
and disconneaed. As a receiver, two levelling bottles 
were found vastly su{>erior to a burette, the glass stop- 
cocks of the latter giving continual trouble by the aAion 
of the caustic potash upon them. I found that gas could 
be removed from a levelling bottle without the loss of a 
particle, if a perforated rubber stopper containing a capil- 
lary tube, which reached just even with the narrower 
end, was by a slight twist forced tightly into the neck of 
the bottle. In this way a regular funnel- shape was ob- 
tained, and the oxygen could be withdrawn without the 
slightest bubble remaining. The other end of the capil- 
lary was fitted with a short piece of vacuum tubing and 
screw pinchcock, which worked incomparably better than 
the glass stopcocks. The larger capacity of the bottle 
was favourable for the volume of oxygen evolved, and its 
8)iape offered superior facilities for the absorption of car- 
hpn dioxide. 

For the aAion of the oxygen on hydriodic acid through 
the medium of nitric oxide, various devices were tested. 
Passing it diredly into nitric oxide over a solution of 
hydriodic acid in a Hempel absorption bulb was found to 
yield low and irregular results, due doubtless to the 
formation of nitric acid wherever the nitrogen trioxide or 
peroxide, as the case might be, met water in which the 
nvdriodic acid had been exhausted, — as, for instance, 
silong the sides of the bulb. Shaking the bulb as the 
oxygen entered improved the action, but was not sufiS- 
cient. It was evident that, for a complete adion, the 
hydriodic acid solution must be strong; and on the spot 
where the higher oxide of nitrogen is formed; and to 
avoid excessive use of the iodide the volume of water 
must be kept at a minimum. Letting a solution of hy- 
driodic acid saturated with nitric oxide flow slowlv into 
the Hempel bulb in which the oxygen was contained over 
water, was so slow in its adion that a quantitative test 
was not applied. The plan of mixine the two gases 
iinder a strong solution of hydriodic acid by means of two 
capillaries with adjoining openings, was more effedive 
and rapid, but it was wasteful of nitric oxide, which for 
complete adion would have to flow in continual excess, 
whereas only a small amount of nitric oxide would really 
be necessary for the readion, since it could be used and 
rie-used for the transfer of free oxygen to the hydriodic 
i^cid. A simple piece of apparatus was then devised to 
meet all these conditions. It consisted of a xoo cm.* 
bulb pipette, cut off short at either ends with stopcocks 
sealed to both stubs. The delivery-tube of one of the 
stopcocks was cut off rather short after being tapered and 
restriaed so as to hold a rubber conneder tightly, while 
the other delivery-tube was left long enough to reach to 
the bottom of an Erlenmeyer beaker. It is a convenience 
to have these conduding tubes 3 or 4 m.m. in diameter 
rather than capillaries, since for the various connexions 
all air may be expelled from them by displacement with 
wMer, which is easily accomplished by using a long- 
nozzled wash-bottle. By attaching the shorter end to an 
ordinary water-pump the air was partially exhausted, 
when the stopcock was closed, and the bulb disconneded 
and lowered into a solution of hvdriodic acid of approxi- 
mately known strength, obtained by acidifying potassium 
iodide with hydrochloric acid. When the desired amount 
of liquid had been drawn in, the stopcock was closed and 
connexion made with the carbon dioxide, by which all 
residual air was expelled. Then the bulb, held so as to 
prevent the escape of the liquid, was again exhausted by 



attachment to the pump. After about 10 cm.* of nitric 
oxide were admitted, attachment was made to the receiver 
containing the oxygen, which was allowed to enter slowly 
under the diminished pressure within the bnlb, and with 
continuous shaking of the contents of the latter. The 
latter precaution is essential to the process, as otherwise 
there is imperfed distribution of the hydriodic acid and 
the danger of forming nitric acid. But when the solution 
of hydriodic acid is kept strong, and the shaking continued 
while the oxygen enters and for a minute or two after- 
ward, depending on the rapidity with which it was ad* 
mitted, the oxygen may be allowed to enter quite rapidly 
without any fear of imperfed adion. The oxygen being 
immediately utilised, the partial vacuum is effeded only 
by the heat generated, which is scarcely noticeable. As 
a rule, the bulb and contents were well cooled before the 
oxygen was admitted. 

(To be continued). 



PROCEEDINGS OF SOCIETIES. 



CHEMICAL SOCIETY. 

The following are the abstra^s of papers received during 
the vacation, and published in the Transactions : — 

X04. ** HomonucUal Tri-divivativis of Naphthalint,^ 
By Raphael Meldola, F.R.S., and Frederick William 
Streatfeild. 

Dibromonitronaphthalene, CioHsBr'NOa'Br (1:2: 4), 
m. p. 1x7% has been prepared by the authors and submitted 
to further study. The corresponding dibromo-iS-naphthyl- 
amine consists of white silky needles melting at xo6*io7* ; 
the acetyl-derivative melts at 220—221^. When this 
dibromo-/9*naphthylamine is diazotised in the presence of 
an excess of mineral acid and the diazo-salt solution 
boiled with water, the NHa-group is not replaced by 
hydroxyl, as in the normal Oriess readion, but bromine 
is displaced, and a diaxoxide formed in accordance with 
the scheme — 

Br O 

C,oH4Br<.?.f.^. -> C,oH4Br<| +HBr. 
Ma'Uln Na 

The diazoxide has the constitution O : Na : Bra i : 2 : 4. 
It consists of ochreous needles, soluble in boiling water, 
and decomposing at 148 — 151^. It is reduced by tin and 
hydrochloric acid to ^-amidoni-naphthol, and bromine 
and glacial acetic acid converts it into dibroma<i-naphtha« 
quinone, m. p. 2i6^ 

Chlorobromo • fi - naphthylamine, CxoHcCl'NHa'Br 
{1:2: 4), was obtained in the form of white silky needlea 
melting at xo2 — 103°; the acetyl derivative at 218^, the 
benzoyl derivative at 185—186". By nitrous acid this 
chlorobromo - 3 - naphthylamine is converted into the 
diazoxide, above described, in the presence of excess of 
mineral acid ; in its absence the diazoamide, 
CxoHsClBr-Na'NH'CioHsClBr, is formed. This com- 
pound is very stable for a diazoamido«compound, and 
crystallises from toluene in yellowish needles melting at 
205—210% with decomposition. The authors also show 
that iodine chloride is an excellent reagent for preparing 
iodine derivatives of the acetnaphthalides, both a and fi. 
They give the melting-points of the following com* 
pounds:— CxoH4l-NH Ac (4;!). 197'; CxoHs'NOa-I NHAc 
(2:4:1); CxoHs'NOa'I'OH (2 : 4 : i), 150'* (shrinking at 
147°) ; CxoHj-NOal-OCaHj (2 : 4), 104— 105% The potas- 
sium sail of the nitroiodonaphthol has also been prepared 
and analysed. 

X05. ** Thi Ethtreal Salts of the Optically Active Lactic 
Chloropropionic, and Bromopropionic Acids," By J. Wax<* 
LACE Walker, M.A. 

The methyltc, ethylic, and propylic ethereal saHt of 



lfov.tt,l8«S- f 



Derivatives of Beta-Resonylic Acid. 



253 



adhre UAic acid were prepared by the adion of the alkyl 
iodidea on the anhydrona ailver salt. From the ethereal 
ladJktea the corretpooding bromopropionic salts were pre- 
pared by the adion of phosphorus pentabromide. For 
ootb series of salts there is a constant difference in rota- 
tory power, in the first case of 5*5^ in the second of 14*2^ 
between two adjacent members. The ethereal chloro- 
propionates were prepared by the adion of phosphorus 

Gmtacbloride on ladic acid. These bodies possess a 
gb degree of optical adivity, and the values given in 
this paper are much higher than those found by Le Bel, 
Waldeo, and Frankland and Henderson for such of the 
aabetanoes as they have examined. The observed results 
do not agree with Guye's hypothesis. 

' X06. **Sotiu N$w AMocompounds,** By Charles 

lflI.L8. 

By the adion of nitrosobenzene on aniline dissolved 
in acetic acid aaobenzene is produced (Baeyer, Bir,, vii., 
1638). The author has extended this readion, and has 
picpared the following substances : — 

m-AutyUmidooiohtntint^ m. p. 130 — 131" C. On 
bjrdfolytta with caustic soda it gives m^amidoagohtnttni^ 
ciystauising from light petroleum spirit in long, silk^, 
orange ncMlea, m. p. 56—57* C. Readily soluble in 
alcohol, acetic acid, ethyl acetate, acetone, chloroform, 
beoaeoe, and ether. C6H5*Ns*C«*H4*Ns*C6H5, Jipara- 
diptumyldisoMOpkin^UtUt prepared by the adioo of nitroso- 
boDsene on ^•amidoasobensene. p^BenjintaMotolugng 
formed by the adion of nitrosobenzene on ^-toluidine, 
also by the adion of ^ nitrosotoluene on aniline. 

The following compounds are also described :~ 

P'B4nMinia9otolu€n4Sulphonic Chloridt, p-BtnMituaMO' 
otu4Uolmd4, C6H,*CH,NHAcN:N CeHs (1:2:4). 
m-Amido p^binxeMaMotofuint. Binzem - o • omo • o • actt* 
Ulmdi. C6H4*NHAc,CH,*N:NC6H5 (1:2: 3). m^Amido- 
h9mK4n€'0-aMotolu4ni, CeH^NHa'CHj-Na'CeHs (i : 2 :3). 

X07. ** Sotm Derivativis of Maclurin,** By C. S. Bbd- 
roao and A. G. Pbrkin. 

When an aqueous extrad of old fustic {Morus Unctoria{ 
is treated with a solution of diazobenzene sulphate, a 
•olooriiig-matter is produced. Tbe chief constituents of 
old fostic are, morin, Ct3Hio07, and maclorin, CxjHxoOei 
only the latter reads readily with diasobenzene. 
Beozeneaiomaclurin,— 

C,3H806(C6H3-Na)a, 
o- and ^tolueneazomadurin, /-nitrobenzeneazomaclurin, 
and roaclurinazobenzene-/-sulphonate of sodium have 
also been prepared. These substances dye wool and silk 
orange-coloured to deep brown shades. Maclurin, by the 
adion of reducing agents, yields phloroglucin and proto- 
catechnic acid, and ts considered to be a pentahydroxy- 
benzophenone, C6H,(OH)2'CO*C6Ha'(OH)3. 

Phloroglucin combines with 2 mol. props, of diazoben- 
zene, while no readion takes place between this latter and 
protocatechoic acid. The constitution of benzeneazo- 
madnrin should therefore be thus represented, — 
OH 
CfiHaCOHjaCO ^^ N:NC6H3 

OH 'vJ OH 
C6H3N;N 

108. ** Tk$ Consiituints of ' Ariocarpus inUgrifolia.* '* 
By A. O. Pbrkin and F. Cope. 

Ano€itrpus iniigrifolia is the well-known Jack Fruit, 
cultivated in India, Burmah, and Ceylon, it is much 
esteemed for carpentry, and is used in conjuodion with 
alum as a yellow dye. It contains a yellow colouring 
matter of the formula CicHioO^, identical with morin, and 
a substance of the formula Cx3Hxa06, to which the name 
tfomomMclurin has been given. With diazobenzene it 
^Ids a compound, Ci3Hie06(C6H3Na)ai crystallising in 
scarlet needles, which dyes unmordanted wool and silk 
orange to orange-red shades, but which does not dye with 



mordants. When boiled with dilute acids, cyanomaclurin 
yields red-brown produds, resembling in charader -the 
so-called "anhydrides** of catechin, which can be pro- 
duced from this latter substance in a similar way. That 
first formed dissolves in hot water and dilute alkalis, but 
by longer treatment becomes more sparingly soluble, and 
the final produd obtained is insoluble in dilute alkalis and 
the usual solvents. No glucose is produced during this 
readion, so that cyanomaclurin is not a glucoside. The 
study of this substance will be continued. 

109. " Optically Activt Miihoxy- and Propoxy'iuccinic 
Acids.'* By T. PuRWB. F.RS., and H. W. Bolam, B.Sc, 

The authors have resolved inadive methozy* and 
propoxy-succinic acids into their adive components, the 
cinchonine and strychnine salts being made use of in the 
case of methoxysuccinic acid, the strychnine salts in the 
case of the propoxysuccinic acid. 

Rotations of the acids in water and different organic 
Bolvenu are given, with the rotations of aalu of both 
acids in aqueous solution. 

xxo. '* BthiTial Salts of AcH9i Mitkoxy- and Btkoxy- 
Snccinic Acids." By T. Purdib, F.R.S., and S. William. 
SON. Ph.D. 

Inadive methoxy- and ethoxy-succinic acids were re- 
solved into their adive components by means of thdr 
strychnine salts. Observations on the adivity of the 
various strychnine salts in aqueous solution were made, 
and results obuined in accordance with the law of 
Oudemans. 

Methyl., ethyl-, propyl-, and butyl-, methoxy-, and 
ethoxy-succinates, and the isopropvl and isobutyl salts of 
ethoxysuccinic acid, were prepared by the adion of their 
respedive iodides upon the silver salu of the acids, and 
their rotations observed. 

The specific rotations of the adive acids in water and 
various organic solvents were also taken. A discussion 
of the results obtained is contained in the paper. 

xxz. '* Not$ on thg Production of Potassium Platmi* 
chloride,** By E. Somstadt. 

Dry potassium platinichloride, when heated with mer- 
cury, ts decomposed according to the proportion of 
mercury used. 

(I). 2KCl,PtCl4+4Hga2KCl«»-Pt+4HgCl. 
(2). 2KCl,PtCl4+2Hg-2KCl-|-Pt-|-2HgCla. 
The decomposition begins even below 100^ C, and ia 
complete at a lower temperature than is required to expel 
from the containing vessel the mercurous or mercuric 
chloride produced. 

In treating small quantities of the platinichloride, the 
mercury is placed in a porcelain crucible, and covered 
with platinichloride, in the proportion of about two parte 
of mercury to one of aalt. Heat is applied very gently, 
to avoid loss through boiling, till the readion is coropletCt 
when the heat is raised to expel the mercurous chloride. 

When larger quantities are decomposed, the salt ia 
preferably triturated with the mercury, and gently heatedt 
so as to avoid a too sudden or violent readion. 

Additional Note by Author. — Dry ailver chloride is not 
decomposed by mercury, even at a red heat ; nor when 
mixed or combined with a platinum salt. 

X12. ** Orthobcnzoic Suiphinide.*' By Wiluam J. PoPB. 

The author finds that pure orthobenzoic aulphioide in 
large well-defined crvstals may be obtained from the 
commercial mixture known aa '* aaccharin,'* by crystal- 
lisation from acetone. Crystallographical meaaurementa 
aie given. 

113. •* Dirivativis of fi-Rcsorcylic Acid.** By A. O. 
Pbrkin. 

The principal produd of the adion of methylic iodide 
upon /S-resorcylic acid is a substance crystallising in 
needles melting at 76~77°« and having the constitution 
C6Ha'Me(OMe)*OH*COOMe. It appears probable that 



254 



Freezing-paints of Stiver and Gold. 



I CpftlllCAL MSW«, 

I Hov. as« 1805. 



the hydroxyl group in /S-resorcylic acid, which resists me- 
thyUtion, is in the o-position to the carboxyl group. 
' The principal produd of the adion of ethylic iodide 
upon /Sretorcylic acid is insoluble in alkalis, and contains 
but two ethoxy groups. It has the formula — 
C6Hs(OE0(OH)COOEt. 

The adion of methylic iodide upon resacetophenone 
has been stiidied, but the results have been anticipated 
by Qregor {Monatsk., 1894. ^^*t 437)* T^^^ principal pro- 
dud is a substance having the constitution — 
C6Ha(OMe)*Me(OH)COCH3. 
insoluble in alkalis, and resembling the results of the 
adion of methylic iodide upon /8-resorcylic acid. 

It appears probable that the insolubility of the methyl 
and ethyl ethers of /3-resorcylic acid and resacetophenone, 
which apparently contain a free hydroxyl group, is due to 
the fad that the oxygen of this latter has assumed the 
ketonic form. The constitution of the two former sub- 
stances would therefore be — 

OCH3 OCaHj 



n 



H-CHj 



J O 
^COOCHs 



COOCaHj. 



Preliminary experiments on the methylation of gall- 
acetophenone have yielded a substance melting at 76— 77^ 
apparently a dimethyl ether, C6H2(OMe)a'OHCO'CH3. 

QalUu9tophtfum$ oxim$, C6Ha(OH)3*C:NOH*CH3, and 
qmnacitofhinoM oxims, C6H3(OH)a'C:NOH*CH3, were 
also obtained. 

1x4. ** Not$ on th4 Gravimitrie Estimation of hialtou 
by Pihling*s Solution.** By T. A. Glbndinnino. 

The specific cupric- reducing power of maltose possesses 
a different value according to whether potash or soda is 
the alkali employed in the preparation of Fehling*s solu- 
tion. Under the conditions of experiment given, the 
reducing powers to be attributed to maltose are- 
Soda, K3^a6z. Potash, K3.86"64. 

On making comparative analyses of starch -transforma- 
tion produds with the two kinds of Fehling's solution, 
identical results were obtained, provided the respedive 
values of K were used. 

No such difference occurs in the case of dextrose or of 
invert sugar. 

X15. " Studies in th$ Malonic Acid Siriis.** By 8. 
RuHBHANM, Ph.D., M.A., and K. J. P. Orton, B.A. 

The authors have investigated the adion of ammonia, 
hydrazine, and phenylhydrazine on dibromomalonamide. 
Ammonia yields diaminomalonamide,C(NHa)a(CONH2)a; 
and hydrazine and pbenylhydraxine give the hydraaone 
and phenylhydrasone respedively of malonamide. 

Fuming nitric acid ads on malonamide, forming nitro- 
malonamide. Aniline, when heated with nitromalon- 
amide until ammonia ceases to come off, yields diphenyl- 
nrea. 

On redudion of nitromalonamide with sodium amalgam, 
aminomalonic acid is obtained. 

By permission of Professor Claisen, the authors have 
investigated the adion of hvdraxine hydrate on ethyl 
ethoxymethylenemalonate. They obtain a result which 
does not agreee with that of V. Rothenberg. 

116. ** Mireury P4rchlorat4s,** By M. Chika8hio&. 

Mercuric perchlorate is not anhydrous, its composition 
being Hg(C104)a.6HaO. It slowly loses, in a desiccator, 
acid and water, and effloresces. In the air it is very deli- 
quescent (SeruUas). When heated, it melts completely 
at 34^ (in drv air) ; as the temperature rises to 150", it 
very slowly decomposes, giving off water and perchloric 
acid, while a white basic perchlorate, Hg30a(C104)2» is 

ft, permanent at that temperature. If the salt is heated 
a long narrow tube, it may be kept in a bath at 400^ 



for any time, without permanent decomposition, boiling 
freely and retaining its transparency, and, when cooled, 
solidifying unchanged. Whilst heated it is, however, 
continuously decomposing into basic salt and acid and 
water ; but as the acid and water vapours condense and 
flow back, the salt is continuously re-formed, and preaenta 
only the phenomena of ebullition. 
Mercurous perchlorate has the composition — 
(HgC104)a,4Ha0, 
according to the author; Roscoe found 6HaO. lo a 
vacuum desiccator it loses in two weeks 2HaO and a 
very little acid, and then ceases to lose weight. It is 
slowly decomposed by heat, even at looP or Im, in dry 
air, first losing water and perchloric acid ; then gradually, 
from 150^ upwards, becoming mercuric salt, and yielding 
chlorides and a little chlorate. It resembles mercuric 
perchlorate in its decomposition, but does not show the 
phenomena of fusion and ebullition. According to 
Roscoe, mercurous perchlorate does not lose weight in a 
vacuum over sulphuric acid, or at zoo*. 

117. '*«-£lAyf#iM Dihydroxylamim Dikydrokrotmidg.** 
By C. M. LuxicooRB, D.Sc 

When ethylene bromide ia heated with a solution o£ 
hydroxylamine in methyl alcohol to zoo**, two moto. of the 
latter combine with one of the former to form the dihy* 
drobromide of ethylene dihydroxylamine, a white crjratal- 
line substance, soluble in water and alcohol, insolable in 
ether. When reduced with hydriodic acid, all the nitro- 
gen is obtained as ammonia. The constitution of ihn 
subsunce is therefore— 

CHa-ONHa-HBr 

CHa'ONHa-HBr, 
and its formation lends some support to the view that 
free hydroxylamine has the strudure 0=:NH3. 

Ethylene oxide also reads with hydroxylamine, forming 
apparently the base correponding with the hydrobromide 
described above. 

118. *• Thi alligid Isomsrism of Potassimm Niiroto* 
sulpkati. By C. M. Luxmoorb, D.Sc 

rotassium nitrosotulphate, whether prepared by the ab- 
sorption of nitric oxide, by potassium sulphite, or by the 
absorption of a mixture of sulphur dioxide and nitric 
oxide by potassium hydroxide, has always the same pr«^ 
perties. Hantxsch's silver salt, (KAgSNaOs), baa been 
obtained from specimens prepared m these diffierent 
ways, and showed the charaderistic behaviour deacribed 
by him. 

Potassium nitrososulphate reaches a temperature of about 
134** (as indicated by a thermometer embedded in the salt) 
before it explodes, the gradual and quiescent decomposi- 
tion into potassium sulphate and nitrous oxide that pre- 
cedes the explosion furnishing the heat that raiaea the 
temperature of the aubstance above that of the bath in 
which it is heated. 

Pelouxe's account of the properties of this substance 
can be completely reconciled with the recent observationa 
of Hantxsch and of Divers and Haga, with the exception 
of the statement that it loses no weight when heated to 
zio% which is evidently a mistake. Five minutes* heating 
below 105** causes a loss of weight of 2k per cent. 

There is no evidence to warrant the suggestion of 
Hantxch that Raschig's first salt is isomeric with potas- 
sium nitrososulphate, nor can it be regarded as identical 
with the salt prepared by Davy and Pelouae. 

X 19. •« On thi FruMing.points of Sitvir and Gold,** By 
C. T. Hbycock, F.R.S., and F. H. Nevillb. 

The authors draw attention to the close agreement be- 
tween the determination of the freezing-point of gold, by 
Callendar, in 1892, and their own determinations in 1894. 
The platinum temperatures differ by a few degrees, but, 
when reduced to the scale of the air thermometer by the 
tame method, the two results do not diffitf by more than 



/ 



CBBHJCAL NbWS. I 

Nov. 23, x8«5. f 



Colliery Explosions. 



255 



one degree. The anthors farther consider the influence 
of various gases on the freezing-point of silver. They 
find that the highest and steadiest freesing-points are oh- 
Uined in the presence of free hydrogen or of coal-gas, and 
that nitrogen or carbon dioxide produce little or no depres- 
sion. They find that the well-known effed of oxygen on 
the freeaing* point of silver may amount in extreme cases 
to a depression of 20^ C, but that the oxygen can be re- 
moved by the adion of nitrogen or hydrogen. 



NOTICES OF BOOKS. 



The Origin and RationaU of Colliery Explosions: 
Founded upon an Examination of the Explosions at 
the Timsbury, Albion, Malago Vale, and Llanerch 
Collieries ; and upon the principal phenomena of the 
Disasters at the Abercame, Alltofts, Altham, Apedale, 
Blantyre, Bryn, Clifton Hall, Dinaa, Elemore, Hyde, 
Llan, Mardy, Morfa, Mosafields, National, Penygraig, 
Risca, Seaham, Trimdon Grange, Tudhoe, Udstone, 
and West Stanley Collieries. By Donald M. D. 
Stuart, F.Q.S., Mining and Civil Engineer, Author of 
•* Coal- Dost an Explosive Agent.*^ Bristol : J. Wright 
and Co. London : Simpkin, Marshall, and Co., Lim. 
New York: Hirschfeld Bros. 1895. Crown 4to., pp. 
144. With two Plans. 
When colliery explosions first began to attrad public 
attention, they were considered solely due to so-called 
** fire-damp,'* t.#., methane or light hydrogen carbide, 
which if minaled with atmospheric air forms, of course, a 
violently explosive total. To combat this serious evil, 
two distind methods were devised. On the one hand, 
the ventilation of the mines was improved so that methane 
might be swept away as rapidly as it was generated, and 
might not be anywhere present in the mine in an explo- 
aive quantity. On the other hand, there was the safety- 
lamp in Its various modifications which was to prevent 
any inflammable gas from being ignited by the lights used 
by the colliers in working. That much disaster was pre- 
vented by these two agencies is beyond all question ; but 
still expioaioos occurred ftom time to time, though less 
frequently in proportion to the number of men employed 
underground and the weight of coal raised. To account 
for these calamities it was alleged that the ventilation 
was defedive, or that the men carried down matches or 
picked the lock of their aafety-lamps. Both these charges 
were doubtless true in not a few cases; but there still re- 
mained a balance of mischief not yet accounted for. It 
was therefore suspeAed^and it was ultimately demon- 
strated—that there must exist some other agent which 
might give rise to explosions, either alone or in conjunc- 
tion with methane. This was found to be coal-dust, 
which has been studied by Prof. Galloway, and to a greater 
extent by the present author. Still, however, it was con- 
tended hy some experts that coal- dust alone, in the total 
absence of methane, could not occasion an explosion. 
The Timsbury disaster, however, supplied the needed 
crucial instance. The Timsbury collieries have been 
worked with open lights for about seventy years, and 
during all the working no fire-damp has been deteded. 
The charaAer of the explosion, which took place in the 
present year, differed entirely in its features from those 
unquestionably due to fire-damp. In the latter, a blast 
seems to have swept through the workings, from end to 
end, occaaioning wreckage everywhere. In the Timsbury 
disaster we have a series of eighteen distind explosions at 
very considerable distances from each other. At the 
points of these explosions there was the usual devastation, 
falls of roof, shattered doors, &c., but in the intermediate 
spaces there was no evidence of violent forces. 

A further charaAeristic of the two kinds of explosions 
appears on comparing the afterdamp. Where carbonic 



acid is present in quantities exceeding 2*2Z per cent, 
candles are instantly extinguished. The first physiologi- 
cal adion encountered is difficulty of breathing, which 
becomes very marked if the proportion of carbon dioxide 
reaches 3*38 per cent. Persons who have been exposed 
to such an atmosphere compare its effieds to those pro* 
duced by violent running ; whilst, according to Dr. Hal- 
dane, a proportion of 8 per cent is fatal. 

The efiieds of ** white-damp " are different ; lights are 
not extinguished, so that the only indication of danger is 
the physiological adion. There is felt a smarting in the 
eyes and nose, the legs tremble, and giddiness is experi- 
enced, and there is imminent danger unless an instant 
retreat into the air is pradicable. In the spaces inter- 
mediate between the points of explosion some of the men 
were found lying dead, but not mutilated, and their lamps 
had not been extinguished, but in some cases had gone 
on burning until all their oil was consumed. 

At an explosion in a similar non-fiery mine (Malago 
Vale colliery) ** the night bailiff was found unconscious, 
his safety-lamp in his hand, still burning, though it had 
been exposed to the entire gaseous produds of the explo- 
sion for nearly two hours." 

The immediate cause of the explosion at the Timsbury 
colliery seems to have been the remarkably dry condition 
of the mine and the error of James Carter, who seems« 
in firing a " shot,'* to have used a much larger quantity 
of powder than was necessary, and to have used as 
tamping a mixture of coal-dust and oil. The excessive 
charge was partly blown out into the dry coal-dust, and 
set up a process of destrudive distillation, liberating com- 
bustible gases. It will be perceived on inspeding the 
plan that the successive explosions took place where the 
gases met with a sufficient volume of air (f.#., oxygen) to 
form an explosive mixture. 

Mr. Stuart's recommendation for the prevention of 
similar catastrophes is highly judicious. He proposes 
that in such dry mines the coal-dust should be kept well 
and permanenthr moist ; especially at the spots where a 
shot is to be fired the floor and the sides should be 
rendered quite sloppy. The evaporation of such a quan- 
tity of moisture would consume any unnecessary and 
dangerous heat-energy. 

Concerning the proposed use of *'high " explosives in 
place of powder for blasting, the author does not consider 
that our experimental knowledge is sufficient to admit of 
a decision. 

Mr. Stuart, by the produdion of this unpretending work, 
has laid the mining interests of this country under deep 
obligation. 



Our Chemistry of Nutrition: a Contribution to the 
Dodrine of Foods and Nutriments. (** Unsere 
Nahrungs • Chemie : ein Beitrag zur Futter und 
Nahrungs-mittel lehre "). By Emil Pott. Munich : 
Theodor Ackermann. 1895. 8vo., pp. 104. 
Thb author, whilst duly recognising the value of the 
initial steps taken by Boussingault and Liebig towards 
a chemico-physiological development of the principles of 
animal nutrition, complains, with the fullest right, that 
we have come to a lamentable stand* still. The attempt 
to decide summarily on the nutritive value of the different 
foods according to their percentage of certain constituent 
groups is, he reminds us, as one-sided as that to deter- 
mine the fertility of a soil simply by the proportions of 
nitrogen, potassium, and phosphoric acid. He submits 
the following propositions: — In order to determine the 
value of a food, it is necessary to ascertain in what forms 
it contains those substances which diredly or indiredly 
take part in the nutrition of the animal body. Nor must 
we forget that we have not yet even an approximate 
knowledge of the individual constituents of foods. 

The nutritive effed of a food varies according as it 
is to be supplied to ruminants, to horses, or to swine* 
Nor must the physical stmdure of a food be negleded. 



256 Inadequacy of Aids and Facilities for Scientific Research. 



f OUBMICAL MBVS, 

• liov. at, 1695. 



' Different races, and even individuals of one and the 
same race, have a different power of utilising food. 

The value of the constituents of food is very unequal, 
according as the animals consuming them are destined to 
yield milk, flesh, fat, to exert mechanical power, or are 
reserved for propagation. 

* Finally, before we can decide on the nutrient value of 
any substance, we must learn in what state or admixture 
it is supplied for consumption. 

The author shows that digestion is a far more compli- 
cated process than it is commonly supposed. In addition 
to that form of digestion effe^ed by the secretions of the 
animal concerned, there is also a ** microbic digestion,** 
effeded by the micro-organisms which accompany the 
food, especially of the herbivora. We have never met 
with an account of the results of a course of experiments 
made— or proposed to be made?~by Pasteur to decide 
on effeds of diet completely sterilised. 

In connexion with these propositions, the author puts 
forward a number of interesting questions concerning the 
known adion of minimal quantities of certain foods or 
condiments. Here there is urgent need for careful experi- 
mentation. This brings Herr Pott to the question of the 
flavours and odours of foods, and to the consumption of 
articles which can scarcely be comprised under the two 
categories of frame-foods or heat* foods. The recent out* 
cry against so-called excitants or stimulants (coffee, 
beer, wioe, &c., in the case of man) applies also to the 
lower animals, and with equal injustice. Von Pettenkofer, 
in reply to the agitators who proscribe all '* stimulants," 
trrespedive of proportion, points out that these substances 
adk like lubricants in machinery, which do not enable 
us, #.^., to dispense with steam-power, but increase its 
efficiency and save the machinery from needless wear and 
tear. The common sense of mankind has shown us— as 
the author quotes from C. von Voit — that what we eat 
with repugnance, or even with indifference, is of little 
value to the S3r8tem. 

This little book is so full of passages which suggest, 
not merely refledion, but experiment, that we must here 
conclude our scrutiny. We can merely glance at a 
passage in which it is pointed out that ** irrigation hay " 
IS deficient, not merely in odoriferous appetising 
principles, but also in albumen and phosphoric acid. 



CORRESPONDENCE. 



ON THB 

INADEQUACY OF AIDS AND FACILITIES 
FOR SCIENTIFIC RESEARCH. 

To the Editor of the Chemtcal News, 
Sir,— I have just read in the Chemical News (vol. Ixxii.i 
p. 224) that, in eulogising very deservedly the work of 
Professor Runge, it was remarked by Dr. Johnstone Stoney 
that *' it would be very advisable at this jun&ure to call 
attention to the unfortunate position in which scientific 
investigation in the British Islands stood in comparison 
with that of at least one other country in Europe. There 
was no scientific man in these islands who possessed a 
laboratory furnished with the appliances for carrying on 
such investigations as those which had just been placed 
before the meeting.'* " An apparatus which would mea- 
sure the half or the third of a tenth-metre would really 
do nothing in an investigation of this kind ; they must 
procure apparatus like the splendid apparatus in Hanover, 
which would measure to the fiftieth part of a tenth-metre 
with certainty.** 

Dr. Armstrong (intervening) said he should like, on be- 
half of the chemists, who had not said anything up to 
that time, to express the universal admiration which they 



must all have of the communications just made to the 
meeting. He had risen at this junAure not merely with 
the objed of saying this, but also in order to corre^ the 
impression which Dr. Johnstone Stoney had just endea- 
voured to make at the instigation of Professor Lodged 
that they were not capable of doing this kind of work in 
the British Isles.*' The DoAor went on to aay that thia 
work had been done by individual effort after the fashion 
usual in England. ** If the idea of making such investi- 
gations as these occurred to men in this country, who had 
the requisite capacity for undertaking them, he waa ante 
the effort would always be made." 

I can quite appreciate the justice of the remarks of Dr. 
Johnstone Stoney, than wnom no one could be better 
qualified to speak on this subje^, of the small encourage^ 
ment and the inadequacy of the aids given to such acieo- 
tific investigations in Great Britain and Ireland. 

According to my experience Dr. Armstrong was not 
happy in his remarks. 

It must be now some eight or ten years since Dc 
Johnstone Stoney and I had a conversation on the desira- 
bility of having a ao-foot Rowland concave grating 
mounted in Dublin, and fitted with all appliances for the 
investigation of spedra. Such an apparatus being necea- 
sary for the determination of certain physical constants, 
ought certainly to be provided. There were no funda 
and no building available. This has a bearing on the 
following circumstances :— In March, 1882, there waa 
published in the youmal of thi Chemical Society a paper 
of mine, entitled ** Note on Certain Photographs of the 
Ultra-violet Spedra of Elementary Bodies," in which it 
was shown that by photographing the spedra of certain 
well-defined groups of elements in series, the grouping 
and the charaders of the principal lines are referable td 
the Periodic Law. 

This paper was merely the preface to two others; the 
first, *' On Homologous Spedra," published in September^ 
1883, in ^hc 7oum, Chem, Sac. ,* the second, ** On the 
Spedrum of Beryllium, with Observations relative to th4 
Position of that Metal among the Elements," published 
in June, 1883. Owing to some untoward circumstance 
the former paper, which was read first, was long delay^ 
in publication, and finally an uncorreded proof was 
printed. On drawing attention to this, the remark was 
casually made to me that it did not matter, as no one 
would ever read the paper. 

It is now necessary to mention that this paper contains 
the following passage with reference to homologons 
spedra—that is to say, those spedra which are similarly 
constituted : — 

** The foregoing data present a considerable addiiion to 
the body of tvidence in sujbport of the view that elementi 
Ufhose atomic weights dijjtr by a constant quantity^ and 
whose chemical character is similart are truly homologous, 
or, in other words, an the same kind of matter in dijfereni 
states of condensation. Their particles are vibrating in the 
same manner, but with different velocities," (See ** British 
Association Report, 1883"). 

J. R Rydberg, in 1890, contributed to the Transaetiotts 
of the Royal Academy of Sweden a paper entitled 
** Recherches sur la Constitution des Spedres d'Emissioo 
des Elements Chimiques,** in which he states that among 
the special contributions to the knowledge of the consti- 
tution of spedra, ** the observation of M. Hartley npoa 
the constant differences of the number of the oscillaticms 
of the components of the double rays of an element is of 
very great importance.'* 

M. Rydberg had remarked upon the double raya of a 
number of elements in 1885, b"^ recognised the fad that 
I had already called attention to this subjed ; and he ttien 
enunciates the law as follows : — 

"The difference between the oscillation- frequencies (or 
numbers proportional to them) of the component of a 
double ray is constant for all the double rays of the same 
species in the same element.** He adds the words^ ** this 
relation applies also to the components corresponding to 



ClIBMICAI. NbW8»I 



Ckemtcal Notices jrom Foreign Sources. 



257 



triplets." My paper dealt with triplets and other groups, 
as well as with doable lines ; it further treated of rays 
with certain charaAers in common ; hence it became ne- 
cessary, in order to include the cases of triplets, to modify 
the statement of the law. 

Mr. J. & Ames, in the Phil. Mag., vol. zxx., p. 33, 1890, 
recognised the law of homology in the spedra of the 
elements as pointed out in my paper, and to him, as well 
as to M. Rydberg, my thanks are due. M. Rydberg, 
however, remarks that, as Mr. Hartley has not made fur- 
ther use of the excellent materials which he has obtained 
by his measurements in the ultra-violet speAra, it may 
be concluded that he has not attributed much importance 
to the relations found. The previous quotation, which for 
the purpose of easy reference is in this letter printed in 
italics, will, I think, show that I was fully alive to the 
importauce of the fads observed, and, indeed, at a later 
date it led to the enunciation of the following modification 
of the Periodic Law:— TA* propertits of the atoms are a 
periodic function of their masses ;*' and, further, it led to 
the view which I have taken care to inculcate at various 
leaures during the past ten years, that, in well-defined 
nonps, the properties of the atoms are absolutely a 
fandion of their masses. 

In other words, one element in a group differs in its 
properties from another, not htcause it consists of anothtr 
kUd of matter, hut because the quantity of matter in an 
atom if it is different. 

No one can study homologous spedra without being 
convinced of the enormous importance to the chemist of 
a thorough investigation into their constitution. To this 
end it was my particular desire to obtain the use of a 
large dynamo and gas-engine for producing arc spedra on 
ao adeauate scale, and by Rowland's method to photo- 
l^raph them for the purpose of carefully studying the 
nnmerical relations between the oscillation frequencies of 
similarly constituted groups of lines both in arc and spark 
spedra. For some time there seemed to be a prosped of 
the Science and Art Department supplying the eledric 
current suitable for such researches; but it was found 
that, even had this been done, there was no place within 
the Royal College of Science where the grating could be 
mounted and used. 

. * An application was made to the Committee of Sedion B 
of the British Association, when it met at Southampton, 
lor a ^um of money in aid of the investigation of arc 
apedra of the elements; but this was not granted. I 
had already spent a considerable sum in such researches, 
pad had used, for instance, a 6 foot concave grating, but 
it was found to be of little value. 

After fruitless endeavours to obtain the means to carry 
on the wQrk in a proper manner, the projeded investiga- 
tion went into abeyance. In the meantime Messrs. 
Kays^r and Runge commenced their work ** Ueber die 
Spedren der Elemente.** In the Pierte Absehnitt, 189X, 
jthey refer to my previous investigation, and of course 
have greatly extended it. 

The recital of the foregoing fads will, I think, be found 
contradidory to the statement of Dr. Armstrong, which, 
as he admits, was intended to reverse the effed of Dr. 
Stoney's Yemarks, and which happened to be singularly 
inappropriate. 

The assistance which I had sought in more than one 
quarter was not forthcoming, and it certainly appears as 
if this was due to a want of appreciation among chemists 
in England of the importance to be attached to an accu- 
rate study of spedra. 

I may add that it has been a source of the greatest 
pleasure and satisfadion to me, for the last four years, to 
observe that. the results published by Professors Kay ser 
and Runge have realised what I had been led to exped 
from observations made years ago with the imperfed 
means at my command — I am, &c., 

W. N. Hartley. 
Boyal College of Science, Dublin. 
^ November 9, 1895. 



CANE-SUGAR AND CITRIC ACID. 

To the Editor of the Chtmical Ntws. 
Sir,— If your readers will kindly compare my three notea 
on this subjed with that published by Messrs. Searle and 
Tankard (Chbicical News, vol. Ixxii., p. 235), they will 
see that these gentlemen, who profess to have repeated 
my experiments, have not done so at all, or at least only 
partially and unsuccessfully. 

I hope to publish later a more complete account, but I 
have not been able to work for more than six weeks past* 
I may state, however, that according to the respedivo 
quantities of permanganic acid and sugar, according as 
sulphuric or nitric acid is used, and according to the tern* 
perature of the day, the produds vary considerably. 

In my experiments tartaric acid, citric acid, sacchario 
acid, and formic acid have been certainly produced, and 
the two first have been separated -and crystallised from 
alcohol. It is perhaps needless to add that citrate of lima 
is not precipitated by boiling unless the liquid is of a 
proper degree of concentration and neutral. 

It would be interesting if Messrs. Searle and Tankard 
would tell us what becomes of the sugar in their experi« 
ments. If they d) not get the acids I have mentioned, 
what do they get ? — I am, &c., 

T. L. Phipson, Pb.D. 

The Cms Mia Laboratory, Patney, 
November 16, 1895. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

NoTB.— All degrees of temperature ate Ceatif rade uolesa otherwise 
eipreated. 

Zeitschriftfur Analytische Chemie. 
Vol. xxxiv., Part 2, 1895. 

Reagent for Monovalent Alcohols.— Beta von Bitto 
{Chtmiker Zeitung), — The author mentions that Schdnn's 
readion takes place only with absolute alcohol, whilst the 
readions of Lieben and Landwehr indicate other sub* 
stances. Hence he proposes a solution of 0-5 methyl violet 
in xooo c.c. water. He adds x to 2 c.c. of this solution to 
the liquid in question, adds } to x c.c. of the solution of 
an alkaline polysulphide, and shakes up. In presence of 
monovalent alcohols the liquid turns cherry-red to violet- 
red, and remains clear. If no monovalent alcohols are 
present the solution takes a greenish blue colour, and 
after some time deposits reddish violet flocks, whilst the 
supernatant liquid becomes yellow. Bi- and polyvalent 
alcohols, carbohydrates, acids, aromatic compounds^ 
phenols, &c., do not yield this readion. With methylic 
and ethylic alcohols, normal and isopropylic alcohol, the 
colour is a cherry-red ; with tertiary butylic alcohol, iso- 
butylic alcohol, isobutylcarbinol, and allylalcohol the 
colour is a violet-red. 

Comparative Studies on the three Isomeric Nitro- 
benzoic Acids. — Oechsner de Coninck. — Prom the 
Comptes Rendus. 

Distinction between Aldebyds and Ketones, 
especially Aldebydic and Ketonic Sugars. —From the 
Comptes Rendus. 

Differences in the Behaviour of Tannin Sub« 
stances with Reagents. — R. Proder (Der Gerber). — 
The author divides the tannins into the following four 
classes :— Those related to pyrocatechin ; those of mixed 
or unknown origin ; those derived from pjrrogallol ; and 
those containing ellago-tannic acid. As reagents he 
uses the foliowing solutions: — {a) Iron-alum, a x per 
cent solution, instead of ferric chloride; the colour 
produced is observed at once, {b) Bromine water 
added to the unnin solution until it smells dis* 
tindly of bromine, observing whether a precipitate is pro- 



«58 



Chemical Notices from Foreign Sources. 



daced or not. (e) Copper sulphate, a i per cent solution 
in slight excess, observing whether the precipitate is 
soluble in ammonia or not. (d) Nitrous acid ; to a few 
ex. of the dilute tanning solution there are added a few 
crystals of potassium nitrite and then 3 to 5 drops of 
decioormal sulphuric or hydrochloric acid. The solution 
is either at once red, and passes through violet slowly 
into deep indigo-blue, or there appears only a yellow or 
brown colouration or a precipitate (see tables), (e) Stan- 
nous chloride and hydrochloric acid ; xo c.c. of the con- 
centrated solution is added to i cc. of the solution of the 
tannin; the colour is observed after standing for ten 
minutes. (/) Pine shavings and hydrochloric acid. 
Reaction for Phloroglucol, — ^A shaving of pine wood is 
moistened with the tanning solution, and, when dry, is 
moistened again with concentrated hydrochloric acid ; in 
presence of phloroglucol, there appears at once alight red 
colour ; catechin and gambler give the readion distinAly. 
{g) Sodium sulphite ; to a few drops of the solution of 
tanning matter there is added a crystal of this salt ; with 
valonia, there appears at once a purple-red colour, (k) 
Concentrated sulphuric acid ; a small test-tube is rinsed 
out with the solution of tannin, which is then poured out so 
that only a small drop remains, and the sulphuric acid is 
cautiously substratified. The coloured ring at the plane 
of oontsA is observed, the liquids mixed and diluted with 
water, (t) Lime water ; the readions are preferably ob- 
tained in a porcelain capsule ; an excess of the reagent 
is not injurious, but it must then be allowed to stand for 
some time. The strength of the tannin solution mutt be 
so adjusted that o'6 grm. solid residue are contained in 
100 c.c. The author's observations are given in detail in 
the form of tables. Upon them follow, also in tabular 
form, the earlier observations of Andreasch. 

Detedion of Hvdroxylamine. — A. Angeli (Gagu. 
Chtmica Italiana), — The author mixes the neutral solu- 
tion with sodium nitroprusside and renders it strongly 
alkaline with soda-lye. On applying heat there appears 
at once a fine magenta colour. An excess of ammonium 
salts interferes. Hydrasin and other inorganic reducing 
agents do not give the above readion. Phenylhydrazin 
gives in the cold a red colour, which disappears on 
heating. 

Elementary Analysis of Highly Volatile Organic 
Substances.— G. Perrin.— The author makes use of a 
special apparatus resembling that used by Zulkowsky and 
Lepez for halogens and sulphuretted substances. 

Quantitative Determination of Hydrazin in its 
Salts. — Julius Petersen (Z«i7. Anor^. Chtmii). 

Determination of /3-Naphthol. — Ktister (Berichte), — 
The author appends a table of corredions to his former 
method. 

Volumetric Determination of Naphthalin, Ace- 
oapbthen, a- and 3-Narbthol, and Analogous Sub- 
itancts.— F. W. KCister (Birichte).^The author's method 
depends on the circumstance that these substances form 
insoluble compounds with picric acid. 
' Determination of Antipyrin.— F. Schaak {AmgrUan 
youmal of Pharmacy), — The author has devised a colori- 
metric process depending on the formation of nitroso- 
antipyrin; its bluish green colour can be recognised in 
dilutions oi x : aoooo. 

Qravimetric Determination of Sugar witb Pehling's 
Liquor. — O. Gaud.— From the Comptes Rendus. 

Determination of the Atomic Weight of Bismuth. 
— R. Schneider. — From the youm, Prakt, Chcmie. 

Atomic Weights of Nickel and Cobalt. — R. 
Schneider.— The mean value obtained for nickel is 
5S7433» an<J t*»*» '»' cobalt 59'3507' 



fCatMICAL Nsws, 
I Hov. as, 189s • 



JUST PUBLISHED. 
446 PH**f»td 104 JUustrtUiomt, Price %%t,^, 

A TREATISE ON THE MANUFACTURE 



MEETINGS FOR^THE WEEK. 

WaoMBsoAV, sTth.— Soci«ty of Arts, 8. ** Locomotive Csrrisces 
for Common Roads,** by H. H. Cuayngbame. 



SOAP AND CANDLES, 

LUBRICANTS, AND GLYCERIN. 

By WM. LANT CARPEKTER, B.S0. 
SMond Bditioo. Revised and Bnlargedby HENRY LBASK. 

CONTENTS. 

Historical Epitome sod Re'ereoces. Theoretical Principles. 

Raw Meteriale : Their Sources and Preparmtioo. 

Raw Materials : Refiaiog, Clarifying, and Bleaching. 

Raw Materials : Their Proximate Analysis. 

Caustic Alkali and other Mineral Salts. 

ManutaAtire ot Household Soaps t The Process of SapontBcatioo. 

Treatment of Soap after its Removal ft'om the Soap Copper: CooUoCi 
Cutting, Drying, Moulding. 

Soap;-Filling and Sophisticating. 

Special Soaps : Household. Laundry, Floating, Disinfeaant, Hard- 
water, Sand, Cold-water, Powders, Maaufsaaren*, Toiki, 
Transparent, Fancy, Solidified, Olvcerin, Ac 

Theory of the AAion of Soap— Its Vafnation and Aaalyaia— Distii- 
btttion and Position of the Trade. 

Lubricating Oils. Railway and Waggon Grease, &c. 

Candles— Raw Materials, their Sources and Preliminary Treatment. 

Processes for the Conversion of Neutral Pau into Patty Acid»— The 
ManufaAore of Commercial Stearin. 

The ManufaAure of Candles and Night-lights— Their Valaa as lUe- 
minants. Glycerin. Bibliography. Index. 

E. & F. N. SPON, X25, Strand, London, 

INSTITUTE OF CHEMISTRY OF GREAT 

BRITAIN AND IRELAND, 

30. Blooicsbury Squarb, London, W.C. 

qPhe NEXT EXAMINATION for the MEM- 

^ BERSHIP of this Institute will be held on TUBSOaY, tae 
7th day of January, 1896. and three following days. 

Two Baamina'ions sre held annnally^ — via.: one in Jaanaryand 
one in July. 

All Candidates must produce evidence of hsving passed a prs- 
limtoary examination in subjeAs of general education, and of having 
taken a syttemstic course of at least three years* study in one of the 
Colleges spproved by the Council ; or having been engaged for two 
years in the laboratory of a Fellow of the Institute, and for two othsr 
years in one of the approved Colleges. 

The Council desire it to be understood that the right to ose the 
letters A.I.C. snd F.I.C. belongs to persons who havepaased through 
the course of study and the examinations prescribed by the Institute. 

A prospedtus containing full particulars of the regulationa for 
admission to the Membership of the Institute, may be obtained from 
Messrs. Blundell, Taylor, and Co., 173, upper Thamea Street, 
London, B.C. Price One Shilling. 

(By Order of the Council) 
J. MILLAR THOMSON, RegSettBT. 

ACETONE — Answering all requirementt. 

.A-CIID -A-OETIO— Ptirest and aweet. 

— IBOIR-A-OIO— Cryat. and powder. 

OITErIC— Cryat. made in earthenware. 

— — Gh-A-XiZLiIO— Froa* b«»t Chineae galls, pbtb. 

S-A.IilOlTIjIO-By Kolbe'a procetfc 

— T-A.IinN"IO— For Pharmacy and the Am. 

LIQUID CHLORINE 

(Compressed in steel cylinders). 

FORMALIN (40)t CHaO)— Antiseptic and Preservative. 

POTASS. PERMANGANATE— Cryst., large and amaU, 

SULPHOCYANIDB OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EM ETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THB ARTS 

Wholes&le Agents— 

A. ^ M. ZIMMERMANN, 

6 A 7. CROSS LANE LONDON, E.O. 



CbbiiicaIi Niwtt I 
Kw. 39. 1895- 9 



Atomic Weight 0/ Helium. 



*5^ 



THE CHEMICAL NEWS 



Vol. LXXIL. No. 1879. 



ON THE ATOMIC WEIGHT OF HELIUM. 
By N. A. LANGLET. 

Although the unitary chartder of helium may still ap- 
pear questionable, it will be not uninteresting to ob- 
USD an approximate determination of its atomic weight, 
or at least of the mean atomic weight of its constituents, 
in order thus to obtain some light on the position of this 
peculiar substance with relation to known elements. 
Alter succeeding in obtaining pure helium, f.#., a gas 
which displays in Geistler's tube only the spedral lines 
ascribed to the hypothetical solar element ** helium." I 
have undertaken a determination of its density as accu- 
rately as the small quantities of the gas at my di&posal 
permitted. 

The helium used in the determinations was prepared 
and purified as follows :— A tube of a metre in length, of 
sparingly fusible glass, was charged with a layer of man- 
ganese carbonate of xo cm. in length, and then filled up 
almost to one-half with a mixture of (3 parts) pulverised 
d^veite and (2 paru) potassium pyrosulphate. At about 20 
cm. from the mouth a plug of asbestos was introduced, and 
the tube was then filled with a stratum of zoc.m. of coarsely 
granular copper oxide. After the mixture was spread out 
m the tube, the copper oxide was heated to redness, and 
the air, as far as possible, expelled by carbonic acid. The 
mixture was then heated for a few momenu in its entire 
length, and the gas evolved at first was expelled by car- 
borne acid to remove any air which might be present. 
The mixture was then, as in organic analysis, slowly 
heated to full redness (commencing at the front), and the 
na which is briskly evolved was colleded in an apparatus 
TOsembling Schifi's nitrometer over potassa-lye at 50 per 
cent. In order to be freed from the last Uaces. of nitro- 
gen, hydrogen^ and water, the gas was passed through a 
long tube of i cm. in thickness (of sparingly fusible 
glass) which contained, in succession, layers of copper 
oxide, phosphorus peotoxide, and powdered magnesmm. 
The copper oxide and the magnesium were heated to 
strong redness. From this tube the gas passed diredly 
into a glass globe holding xoo cc, and previously care- 
fully adiausted. In this manner the density was found 
to be 0-I39 (air-i), or 2-00 (H«i). After weighing, the 
globe was evacuated, the gas pumped back into the gaso- 
meter, and again led through the ignited tube into the 
globe. The weight of the gas had not varied, and the 
density was again determined as 0*139. A small quantity 
of the gas was passed from the globe into a Geissler tube, 
and its purity was tested spearoscopically. It was found 
perfeaiy free from nitrogen, hydrogen, and argon. A 
determination (made by opportunity of an examination of 
the apecific heat of helium) of a quantity of the gas ob- 
tained and purified by the same method gave the value 
0*140. Though these determinations cannot claim any 
greataccuracy, on account of the small quantities of the 
gates employed, we may, without much error, fix the 
specific gravity at 0-14 (air- 1), or 2-0 (H - 1). 

The atomic weight will then be either 2 or 4, according 
aa the mol. contains 2 or x atoms. To decide this ques- 
tion, the speed of sound in helium was determined, and 
from this the proportion was calculated between the 
specific heat at a constant pressure and at a constant 
volume. For this purpose the gas was placed in a tube 
closed at one end by means of a perforated caoutchouc 
•topper. Over the other end a membrane of caoutchouc 
waa extended air-tight, upon which a plate of glass was 
cemented with tallow. The tube was then evacuated by 
of a nanow tube inserted in the caoutchouc stopper 



and filled with helium. After the glass plate had been 
removed, a powerful stream of air was direded rather 
obliquely through a narrower tube against the membrane, 
and thus sounds were obtained, the wave-lengths of which 
could be measured by means of some silicon dioxide in- 
troduced into the tube and set in motion by the vibrations. 
From the speed of the sound found in this manner the 
relation between the two heat capacities was calculated 
as x-67. The low density of helium renders the deter- 
minations uncommonly difficult and somewhat uncertain. 

The molecule of helium contains, therefore, like that of 
argon, only i atom. The atomic weight must therefore 
be taken as — 4. 

Ramsay, after having in a preliminary communication 
indicated the specific gravity of helium as 3*88 (H a x), 
has lately published an extended examination of the 
helium obtamed from different minerals. The numbers 
which he obtains do not differ greatly from each other, 
the mean of all the determinations being 2*x8, t.#., 8 or 9 
per cent higher than the value which I have found. It 
helium, as Lockyer and Deslandres have assumed, is not 
a simple gas, but a mixture of several, the difference 
would be easily explained. But as Ramsay appears to 
have made no spedroscopic examination of the purity of 
the helium which he experimented upon, it is naturally 
not impossible that, in spite of careful purification, it mav 
have retained slight impurities of nitrogen or argon. If 
the density which I have obtained can be regarded as 
correa, Ramsay's helium would contain a mean of 1*5 per* 
cent by volume of nitrogen, or x vol. per cent of argon. 

When this research was undertaken, Ramsay had ob- 
tained from his cliveite merely a mixture of helium with 
argon, and it seemed not possible to separate both gases 
from each other. But as I obtained pure helium (as far 
as it can be ascertained with the speAroscope) from the 
mineral at my disposal, and it was scarcely possible to 
assume that the argon studied by Ramsay could be found 
to be derived from the atmosphere, its absence can be 
attributed only to an accident which may possibly never 
recur. 

I submit that by these circumstances the apparent 
intrusion into a region which belongs to the discoverer of 
helium will be explained and pemuttcd.— ZWtocAn/l/iir 
Anorganischs Ckimi$, x., p. 287. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By J BAN SBRVAIS ETAS. 

(Oootinoed from p. sso). 

Chaptbb II. 

On tub Naturb and Amount op Soliiblb and 
Insolublb Minbral Mattbrs, in thb Aib at 
TUB HioHBR District op Brussbls, and in Rain 

WaTBR. at given times and under OIVEN 

conditions. 

One knows, from researches made in diffsreiit nlaces at 
given times, that air may contain soluble and insoluble 
compounds of sodium, calcium, and potassium, together 
with many insoluble silicatea. The late Robert Angus 
Smith reviewed our knowledge of this snfaje^ in his 
standard work ** Air and Rain.*' * 

Judging by the ver^ great trouble experienced during 
spedroscopic observations of flames burning in the air of 
Brussels and the neighbourhood, one is tempted to be- 
lieve in the existence of large quantities of sodium com- 
pounds, such as sulphates and chlorides, in the air of this 
town. Researches that I have undertaken at very diffierent 
periods have convinced me that this opinion is erroneoos, 

• *< Air and Rsia,** by RobMt Aagas Smith. 
aadCo. 187s. 



26o 



Chemical Researches and Spectroscopic Studies. 



JCRBIIICALMlWt, 

I Nov. 29, 1895. 



at least as regards the higher part of the town, where my 
experiments were made. As a matter of fad, when 
taking from Un to fiftttn cubic nutrts of air as a unit of 
volume, one cannot measure the amount of soluble so- 
dium compounds present It is not so with insoluble 
compounds of sodium and calcium. 

In order to ascertain the quantity of solids suspended 
in free air, when it was as still as possible, I condensed 
the water vapour which exists in such variable quantities. 
It seemed to me, in faA, that, during the process of con- 
densatioHt the water ought to entrap all particles, 0} what- 
ever material, suspended in thb layer of air in contact 
with a surface chilled below dew-point. I effeded this 
condensation on the outer surface of a polished platinum 
apparatus which had been recently washed and then 
heated to redness. The apparatus I used consisted of a 
cylindrical platinum refrigerator with a domed top, 
ao cm. diameter by 30 cm. height. 

The domed top, ntting loosely on the vessel, reached 
a cm. down it, and was provided with a long collar and 
a large tube in the centre. The vessel was two-thirds 
filled with disulphide of carbon ; in the opening in the 
lid was fitted a cork, pierced by a glass tube for bringing 
a current of dry air to the disulphide of carbon, and by a 
thermometer registering j'^th of a degree C. The air 
current was made by bellows or a water-pump, and was 
dried before reaching the disulphide of carbon. When 
the water-pressure was constant, the bellows were able to 
regulate the current so as to obtain and keep a sufiSciently 
low temperature to bring the walls of the vessel below 
dew-point, and as near as possible to 0° C, without 
freezing the condensation water.* 

To the collar of the domed top was fitted a cork pierced 
by a glass tube, meant to condud away the air saturated 
with disulphide of carbon vapour. 

During use the apparatus was freely suspended in a 
slightly inclined position, in order to assist the fall of the 
water. A platinum sheet served to lead the water, as it 
was condensed, into a platinum funnel containing a double 
filter-paper washed in succession with dilute nitric acid, 
with pure water, with dilute hydrofluoric acid, and again 
with pure water, touched at one point the lower part of 
the bottom of the vessel. 

The spout of the platinum funnel passed through a hole 
in a glass plate which supported the funnel, and was 
itself supported by a small platinum dish recently washed 
and ignited to redness, meant to receive the filtered water 
of condensation. 

I then ascertained the amount of water colleded, by 
weighing it in a covered platinum crucible. 

To determine the nature and weight of the bodies left 
in the filter, I made the following arrangements :~ 

Into a platinum dish, of no cubic cm. capacity, pre- 
viously washed and ignited to redness and furnished with 
a spout, was measured one hundred grms, of filtered 
water, which was then evaporated on a bath. When the 
water was evaporated down to about x cc, the liquid 
was transferred into a very small well-polished platinum 
dish, weighing about one grm,, and the weight of which 
I had determined to within two or three thousandths of a 
m,grm. After evaporating the liquid from the very small 
platinum dish on the bath, I put into it the washings from 
the larger dish, and evaporated the whole to a constant 
weight. I then weighed and determined the nature of the 
lesidue. I tested for chlorides with nitrate of silver, and 
for sulphates with chloride of barium. 

The filters, through which the condensation water had 
been passed, were then dried. The inner filter was com- 

* Dariog theu ejcperimentt, when the pressure of the water 
working the bellows was increased, the water ot condensation, in- 
stead ot being deposited in a liquid state, was froxen. The ice pro- 
uced was either quite transparent or opaqut, but tinted either with 
black, like smoky quartx, or with yellowuh gray. An examination 
under the microscope of this ice, or of the water got by melting it, 
plainly showed the shape of the foreign bodies mixed with it. 1 call 
the attention of any one engaged in researches on the nature of tl|e 
particles floating in the air to this point. 



pared with the outer, and both were examined under a 
microscope. After this examination the inner filter was 
folded and re-folded and tied in a fine platinum wire, and 
carbonised at a low temperature ifi a closed platinum 
vessel. 

The carbon was carefully put into the outer envelope 
of a gas jet, to burn it. During combustion one could 
ascertain, by spedrum analysis, the nature of the spec- 
trum produced. 

After combustion I weighed the ash, and determined 
its constituents by using successively chloride of ammo- 
nium,Jluoride of ammonium, and sulphuric acid, all pure. 

The results arrived at were as follows : — 

A. Outer Air.-'Tht condensing apparatus was freely 
suspended outside a window with a south-west exposure, 
looking on to a garden, 9 metres above the ground, which 
is 49 metres above the lower part of the tower and 77 
metres above sea-level, at about 45 cm. from the wall,— 
and a board was used to support articles to be placed out- 
side the window. The apparatus was sheltered from wind 
from the front and sides, from sun, and rain« by movable 
screens, also 45 cm. away from it. Nevertheless the sur- 
rounding air could freely penetrate from above and below, 
as well as circulate in and escape from this enclosed 
space. 

A Bunsen lamp, which could be lighted from inside by 
opening one of the movable window-panes, was put 00 
the board. This lamp was surmounted by a very large 
sheet- iron funnel, communicating with a sheet-iron pipe 
fixed to the wall, to carry off the produas of combustion 
of the coal-gas feeding the lamp. By opening the movable 
pane in front of the lamp, and bringing forward the 
spearoscope, one could at any time make a spedrum 
analysis of the flame, which assisted, as I satisfied my- 
self, to a great extent in the supply of air to the enclosed 
space. 

A thermometer in the shade, and identical with that in 
the top of the apparatus and reaching into the disulphide 
of carbon, showed the outside temperature. 

Having made all arrangements for my experiment, I 
started the pump slowly, so as to bring dry air through 
the disulphide of carbon and lower the temperature to 
dew-point. Owing to the considerable sixe of the appa- 
ratus and the care I took, I was able, at every attempt, to 
fix this point to within about 0*2^. 

ist. With a light west wind :— 

Temperature of the air •• .. iS's** 

Dew point , ,, ,. la'b** 

Weigiit of water condensed .. 125 grms. 

Whilst the pump was working, the temperature of the 
disulphide of carbon was between cP and 3% and an 
analysis of the flame of the Bunsen lamp showed a de- 
cided sodium spedrum. 

Five drops (| c.c) of a 10 per cent solution of 
nitrate of silver nad a perceptible effed on xo c.c of the 
filtered water contained in a stoppered glass tube, with 
its bottom flattened and polished, 15 m.m. diameter, 
and surrounded for its whole length by paper blacken^ 
with lamp-black,— a condition in which the least opales- 
cence is easily noticed. 

One drop of a saturated solution of chloride of barium 
had no effed on ten ex. of the filtered water. After eva- 
porating the mixture down to about half a c.c, the liquid 
was perceptibly clouded. 

The evaporation of xoo cc of the filtered water, 00 a 
bath in the outer air, left a small yellowish transparent 
stain, perceptibly hygroscopic, the weight of which wai 
less than the limit of error of weight, — that is, two or 
three thousandths of a m,grm. ; when heated, this residue 
perceptibly blackened ; when dissolved in a few drops of 
pure water, it made a solution of which a part, when pot 
on to a fine platinum wire loop recently ignited to redness 
was entirely volatilised, colouring a Bunsen jet yellow, 
and showing co analysis a brilliant, though temporary, so- 
dium spedrum without a trace of a calcium spedrum. 



Kov. 39, 1893. f 



Quantitative Determination of Perchlorates. 



261 



even after having moistened the loop with a solution of 
chloride of ammoninm. 

The inner filter, throngh which the condensation water 
had passed, showed, after desiccation, a greyish tint. 
With a microscope one could see numerous black specks 
and bright grey specks, as well as a great number of 
filaments. 

The introdudion of the carbon, made by carbonising 
the inner filter in a closed vessel, into the envelope of a 
B«nsen jet, coloured a great part of it yellow. 

During the combustion of the carbon, spedrum analysis 
showed a sodium spedrum, and a faint and incomplete 
calcinm spedrum, but no trace of the potassium line. 
The weight of the deep brown siliceous ash was about 
0*000085 grm. 

The aim, when dissolved in a saturated solution of 
chloride of ammonium adhering to a fine platinum wire 
loop, and introduced, after slow desiccation, into a 
Bonsen jet, showed a strong sodium spedrum and a faint 
calciam spedrum. but no trace of the potassium line. 

The loop, coated with the ash, was moistened thrice 
with a saturated solution of volatile fluoridt of ammonium^ 
heated each time to a dull red heat, to volatilise the sili- 
ceous sand and the silica from the silicates, and then put 
into the envelope of a Bunsen flame; it immediately 
ooloored it yellow. Spedrum analysis of this envelope 
ahowed the sodium line, but no trace of a calcium or 
potaasium spedrum. 

The platinum wire loop, when moistened with sul- 
phoric acid and pnt into the flame, coloured it yellow, but 
spedrum analysis of the flame did not show the potassium 
line. 

Thus the water of condensation contained a trace of 
soditam in the form of chloride and sulphate, and sodium 
and calcinm in the form of various silicates, whilst silicate 
of potaasium was not present. 

2nd. With a total absence of wind : — 

Temperature of the air . • • • 8*20" 

Dew-point 7*95° 

Condensed water 125 grms. 

At the time of commencing to condense the vapour, fine 
rain had alternated for three days with damp fog, and 
the sheltering screens were quite damp. During the 
time occupied in condensing, which was considerable, 
the temperature of the disulphide of carbon varied from oP 
to 2*5^, and spedrum analysis of the flame burning in air 
failed to show the sodium line. 

Five drops of the 10 per cent solution of nitrate of 
athrer, after waiting for thirty minutes, produced no 
cloadinesa in xo c.c. of filtered water. When the volume 
oi the mixture was reduced by evaporation to about 
half a c.c, a cloudiness appeared on cooling it. This 
was re-disaohred by ammonia. 

The liquid formed by the evaporation of xo c.c. of 
filtered water down to about half a c.c, was slightly 
clouded hy one drop of a saturated solution of chloride of 
barium. 

One hundred cc. of filtered water left, on evaporation, 
a small brown stain, quite distind under a microscope, 
and perceptibly hygroscopic. The weight of it was 
within the limit of error in the weight of the dish (0*003 
m.gnn.). The stain perceptibly blackened when heated ; 
the ressdoe was dissolved by two drops of water, and the 
solotion« when put into a Bunsen flame, showed the 
sodinm line only. 

When the inner filter through which the water passed 
waa dried, it was decidedly grey ; when examined under 
amicroscooe, it showed numerous small black specks, 
and also filaments of various lengths. Combustion of 
the carbon, made by carbonising the filter in a closed 
ireasel, left a trace of decidedly brown ash. During the 
whole period of combustion I saw the sodium spedrum 
to the exclusion of any other. 

Thus, although I was not able by spedrum analysis to 
deled tta« presence of the sodium Ime in the Bunsen 



flame burning in the air which furnished the water of 
condensation, I nevertheless ascertained that it contained 
sodium in the form of chloride and sulphate, since the 
water of condensation contained a trace of these bodies. 
3rd. Favourable atmospheric conditions occurring, I 
checked these latter observations. After fiv$ days* 
drizzle, without Sinsiblt wind, and whilst it continued 
raining, — 

The air temperature being 9*45° 

And the dew-point 9*i5* 

I colleded by condensation X35 grms. of water. 

The screens sheltering the apparatus were thoroughly 
soaked by the rain. Throughout the time the apparatus 
was working, the temperature of the disulphide of carbon 
was between o® ana 2*8^ Spedrum analysis of the 
Bunsen flame burning in the outer air did not show a 
glimpse of the sodium line. 

Five drops of a xo per cent solution of nitrate of silver 
in xo c.c. of filtered water showed no appreciable preci- 
pitate after waiting twenty minutes. When the mixture 
was evaporated down to about half a cc. it perceptibly 
clouded on cooling ; this was re-dissolved by ammonia. 

Ten c.c. of filtered water were evaporated down to 
about half a cc The liquid was slightly clouded by one 
drop of a saturated solution of chloride of barium. 

One hundred cc of filtered water left, on evaporation, 
a small sparkling brown stain, absolutely unweighable. 
When heated, the stain turned black ; the residue, when 
dissolved by two drops of water, and put, in the form of 
a solution, into a Bunsen flame, coloured it yellow. 
Spedrum analysis of the flame showed a brightly* 
coloured, but temporary, sodium line. 

The inner filter through which the water passed, when 
dried and compared with the second filter, also dried, had 
a distind grey tint on the side which received the water, 
and showed under the microscope a number of black 
specks, and also filaments, some long, others short. 
After burning the carbon made by carbonising the inner 
filter, there remained a minute trace of brown ash. 
During the combustion I saw a very faint and transient 
sodium spedrum. 

Thus, although I was not able at any time to deted the 
sodium line in a Bunsen flame burning in the air, never- 
theless the air contained sodium in the form of chloride 
and sulphate, but in an absolutely unweighable quantity 
in X5 cubic metres of air. 

(To be conttoacd). 



THE QUANTITATIVE DETERMINATION OF 

PERCHLORATES* 

By D. ALBERT KRBIDBR. 

(Concluded from p. 2$!), 

It is necessary of course to prevent the access of air 
into the bulb until the acid has been neutralised, to ac- 
complish which, without loss of iodine, potassium car- 
bonate must be used, at least for the end readion. To 
remove the contents of the bulb for titration the two 
delivery- tubes were filled with water, after removing all 
sodium hydrate from the one through which the oxygen 
was entered ; the shorter end cooneded to a supported 
funnel containing a saturated solution of bicarbonate, 
and the longer one inserted into an Erlenmeyer beaker 
containing a saturated solution of bicarbonate in amount 
sufficient— as previously determined — to neutralise all the 
acid taken. By opening that stopcock the delivery-tube 
of which reaches below the liquid in the beaker, the bi- 
carbonate is drawn in by the partial vacuum, with 
liberation of sufficient carbon dioxide to force all the 

* Coatribations from the Kent CbcmicAl Labormtory of Yale Col- 
lege. From the AmiHcam fotmtal oj Scmmm, vol. 1., Odober, 1893* 



262 



Quantitative Determinatian oj Perchlorates. 



I Cbbmical Nbwi, 
I Not. 29, 189$. 



liquid out. Owing to the conteqnent effervescence as 
the liquid gains its exit, the flow must be regulated by 
the stopcoclc so as to avoid loss of iodine, which is pre* 
vented by inclining the beaker so that the bubbles strike 
against its side instead of being allowed to splatter out 
of the opening. To wash out the bulb it is raised almost 
horisontally, so as to prevent the liquid from running 
through, and the upper itopcock opened to admit the bi- 
carbonate from the funnel. Both stopcocks are then 
closed, the bulb disconneded and agitated, after which it 
may be washed with water and admission of air without 
any fear of liberating more iodine. An excess of deci- 
normal arsenic is then run into the beaker and titrated 
back with iodine. 

The many little precautions essential to note for the 
manipulation are in pradice accomplished in a few mo- 
ments. Seven determinations (not counting one which 
was all but completed, when an accident terminated it), 
from the weighing of the perchlorate to the titration, 
were completed in one day : and the results recorded in 
Table VII. show with what reliability. In making the 
series of experiments recorded in Table VII. it was found 
expeditious to have a partial vacuum always accessible 
instead of waiting each time for the exhaustion. This 
was obtained by conneding a vacuum flask with a two- 
holed stopper to an ordinary water pump, and having the 
other perforation fitted with a glass stopcock. The bulb 
was merely attached to the vacuum by a piece of rubber 
tubing ; the stopcock opened and closed immediately, by 
which means a sufficient exhaustion was secured. To 
have the vacuum always in readiness, a valve, described 
in a former article of mine {Amir, yourn, of Science, 1., 
p. 132), was placed in the rubber leading to the pump, 
and when lubricated with glycerin would hold the vacuum 
perfeaiy. The nitric oxide employed was supplied by a 
Kipp generator, in which globules of copper were aded 
npon ^ nitric acid mixed with an equal volume of water. 
To purify the gas evolved from any possible trace of the 
higher oxides, it was first passed through an acidified so- 
lution of potassium iodide in Geissler absorption bulbs, 
the latter one of the three being alkaline. This method 
of generating nitric oxide in a Kipp generator (preferably 
charged with dilute acid and kept warm by immersion in 
hot water when large amounts of the gas are to be drawn 
at frequent intervals) was devised by Professor Oooch, by 
whom it has been employed for some time. It is auto- 
matic and eminently satisfadkory. The hydriodic acid 
was obtained from a solution of potassium iodide con- 
taining I grm. in 10 c.c. ; 30 c.c. being taken for each 
experiment, and acidified with the required amount of 
hydrochloric acid immediately before using, so as to 
prevent any liberation of iodine by the oxygen of the air. 
In those experiments in which more than this amount of 
potassium iodide was employed a correspondingly stronger 
solution of the latter was used, so that the volume of 
water was in all cases 30 c.c. 



KClO« 




Table VII. 






KI 


HCI 


KC10« 




Ukeo. 


takeo. 


found. 


Error. 


Onns. 


C.m.« 


Orm. 


Gra. 


30 


30 


0*1003 


0*0003 + 


30 


30 


O'lOOfi 


0*0006 + 


3-0 


3-0 


O'oggS 


0*0002- 


40 


4-0 


0*1003 


0*0003 + 


30 


3'o 


0*1003 


00003 + 


30 


4-0 


00999 


0*000 X — 


30 


30 


0*1003 


0*0003 + 


30 


4-0 


0*1001 


00001 + 


I-: 


4-0 


01493 


0*0007- 


60 


01999 


0*000Z - 


6-0 


6-0 


02009 


0*0009 + 


30 


30 


0*0099 


O'OOOX — 


30 


30 


0*0100 


0*0000 


30 


3-0 


0*0003 


0*0003+ 



In experiments (40) and (43), during a momentary pause 
in the shaking of the bulb during the absorption, a black 
deposit of iodine began to form on the glass, and the re- 
sult proves the importance of the precaution previously 
given, that the hydriodic acid should be kept hurling 
about the bulb until the adion is completed. The blank 
determination (45) shows a constant error of the process, 
which is about 0*0003+, and will be seen to correspond 
very closely to the average error of the determination. 
The cause is doubtless to be attributed to the trace of air 
which may remain in the bulb or be dissolved in the 
water. Since it can easily be determined and the correc- 
tion made, it does not detrad in any degree from the 
reliability of the determination. 

To determine perchloric acid associated with other 
oxidising agents, it is only necessary to treat the mixture 
with the reagents which this investigation and the one 
referred to has shown to accomplish the redudion without 
affeding the perchlorate; subsequently evaporaUng to 
dryness and treating the residue according to the above 
process, viz., by heating in a current of carbon dioxide 
until decomposition is complete ; colleding the oxygen 
over caustic potash ; allowing it to enter a partial vacuum 
bulb containing a solution of potassium iodide, hydro- 
chloric acid, and nitric oxide under constant agitation ; 
and determining by means of a standard solution of 
arsenic the amount of iodine set free. The method is 
proving applicable also to the determination of oxygen in 
air, or wherever it may be obtained in the free state, 
unless diluted to such an extent with other gases that the 
vacuum would be filled by the diluent ; even this contin- 
gency could be met by enlargement of the absorption- 
bulb. 

Many helpful suggestions are to be credited to Prof. 
Gooch. 



LONDON WATER SUPPLY. 
Report on the Composition and Quality op Daily 
Samples op the Water Supplied to London 
POR THE Month Ending October 3X8T, 1895. 

By WILLIAM CROOKBS, F.R.S.. 

and 

PROFESSOR DBWAR, F.R.S. 

To Major-General A. De Courcy Scott, R.E., 
Water Examiner, Metropolis Water Act, zSyt. 

Loodoo* November nth, 1895. 
Sir, — We submit herewith, at the request of the 
Diredors, the results of our analyses of the 289 samples 
of water coUeAed by us during the past month, at the 
several places and on the several days indicated, from the 
mains of the London Water Companies taking their 
supply from the Thames and Lea. 

In Table L we have recorded the analyses in detail 
of samples, one taken daily, from Od. xst to OA. 31st 
inclusive. The purity of the water, in resped to organic 
matter, has been determined by the Oxygen and Com- 
bustion processes ; and the results of our analvses by 
these methods are stated in Columns XIV. to XVIIL 

We have recorded in Table II. the tint of the several 
samples of water, as determined by the colour-meter 
described in a previous report. 

In Table III. we have recorded the oxygen required to 
oxidise the organic matter in all the samples submitted 
to analysts. 

Of the 189 samples examined all were found to be 
clear, bright, and well filtered. 

We have this month to record an excess of rainfall, the 
quantity measured at Oxford being 285 inches, compared 
with 2*56 inches (the average for 25 years), showing an 
excess of 0*29 inches. The rain was fairly well d^tri- 
buted throughout the month, though more fell in the first 
ten days than later on. There were fifteen days on which 
no rain fell. 



CHuncAf. Hiwtt I 
Not. 19, 1893* I 



Vapour-tensions of Mixtures of Volatile Liquids. 



263 



Compared with the corresponding month of last year, 
the quality of the Thames derived waters shows a marked 
inprovemeot in every resped ; and, in spite of a mach 
heavier rainfall than in September last, the results are 
almost identical 

Our baderiological examinations give the following 
ffMults:^ 

Colonies 
per c.c. 

Thames water, nnfiltered 2603 

Thames water, from the clear water wells of 

the five Thames-derived supplies • • highest 108 

Ditto ditto lowest 30 

Ditto ditto mean 68 

New River water, unGltered 1577 

New River water, from the Company's clear 

water well • • • . . • 41 

River Lea water, unfiltered 3018 

River Lea water, from the East London Com- 
pany's clear water well • • • • 48 

These results show that the Water Companies are able 
to successfully cope with the extra strain put upon them, 
their filtering appliances being in excellent condition. 

We are. Sir, 

Your obedient Servants, 

William Caooxxs. 
Jambs Dbwar. 



ON THE VAPOUR.TENSIONS OF MIXTURES 

OF VOLATILE LIQUIDS.* 

Br C E. linebargbr. 

(Concluded from p. 231). 

Tk$ MoUcular Mass of Liquid Acetic Acid and a Gimral 

Method of DiUrmining Molecular Masses of Liquids, 
Thb data ffiven in the preceding sedion on the vapour- 
tensions of mixtures of acetic acid and benxene, taken in 
connexion with thefaA that the partial tension of benxene 
in its solutions is diredly proportional to its concentration, 
permit of determining the molecular mass of the acid 
when diluted to any degree whatsoever with the hydrocar- 
bon ; and this special case may be generalised so as to 
permit of universal application. Furthermore, if the 
molecular mass of a substance be known in solutions of 
every degree of concentration, it is possible by a little 
extrapolation to pass over to the molecular mass of the 
pore Lquid. It is, of course, assumed in making such an 
extrapolation that no break occurs in the continuity of 
the phenomenon, that is, the addition of very small quan- 
tities of a normal liquid to an associated one occasions 
correspondingly small changes in the degree of complexity 
of the molecules of the latter. 

The way in which I have gone about to get at the 
molecular mass of acetic acid in benxene and toluene 
solution is as follows : — 

In a system of co-ordinates, molecular masses of acetic 
acid from o to zoo were laid off on the axis of abscissae 
(20 inches long), and on the axis of ordinates, the vapour- 
tensions were taken from o to 150 m.m. of mercuiy (15 
inches long). A straight line was drawn from the point 
100 on the axis of abscissae and o on the right-hand axis 
of ordinates to the point o on the axis of abscissae and 146 
(benxene at 35^ 75 6 (benxene at 20*), and ^7*2 (toluene 
at 35*). Upon this straight line must lie all the points 
corresponding to the partisl tensions of benxene or toluene 
dissolved in acetic acid. So points were marked along 
it giving the value of the partial tensions of benxene and 
toluene in solutions containing 10, 20, 30, ftc, per cent of 
acetic acid, the data being taken irom Table XIII. 

* Abridxed from the Joutnal of the American Chemical Society ^ 
VOL sviLTno. S, AoBott, 1895. 



The value of the abscissae which these points determine 
give the number of molecules of acetic acid contained in 
xoo molecules of the mixture. All that has to be done 
now is to solve for every case this problem : Given a mix- 
ture containing m parts of a liquid A, having a molecular 
mass X, and n parts of a liquid B, having a molecular mass 
y ; the mixture is made up of r molecules of A and 1 mole- 
cules of B. What is the value of ji in the terms of y, m, 
M, r, and s ? 

In the case before us we will take acetic acid for the 
liquid A, and benxene, or toluene as the case may be, for 
B; then n is equal to (100— m) and 1 to (loo-r). 

It is easily found that the solution of our problem is— 



m sy 



m(ioo— r)y 
(xoo— fn)r 



In the accompanying Tables, XIV., XV., and XVI., the 
values of m, r, and x are given. 

Table XIV. 
MoUcular Mass of Acetic Acid dissolved 



Per cent ot C,H40, Moll. CaH^O, in xoo 
in liquid mlxtare. mole, of liquid mixture. 



10 
20 
30 
40 
50 
60 
70 
80 
90 
ZOO 



5-2 
106 
x66 
23X 
30*0 
377 
472 
593 
75*6 

lOO'O 

Table XV. 



in Bengem at 35^. 

Molecular mass of 
acetic acid. 

158 
X64 
X67 

173 
X82 

193 
203 
2x3 
227 
240 



Molecular Mass of Acetic Acid dissolved 
Per cent of C«H«0, Moli. C,H«Os in xoo 
in liquid mixture, molt, of liquid mixture 



XO 
20 
30 
40 
50 
60 
70 
80 
90 
XOO 



5-1 

X6*2 
22*6 
29*6 

37*2 

467 

587 
752 

XOO'O 



ill Bengene at 20^ 
Molecular maaa of 
acetic acid. 

x6i 
166 
X72 

»77 
x86 

198 
208 
2x8 
23 X 
244 



Table XVI. 
Molecular Mass of Acetic Acid dissolved in Toluene at 35° 
Per cent of CSH4O, Moli. CsH«0, in too Molecular ma»t of 



in liquid mixtuie. 


molt, of iiquia mixture. 


acetic acid. 


XO 


6x 


159 


20 


X2-4 


X63 


30 


ig-o 


x68 


40 


265 


\1^ 


50 


32-8 


60 


4x3 


196 


70 


51-2 


204 


80 


6x-x 


213 


90 


784 


228 


XOO 


loo-o 


240 



Considering Tables XIV. »nd XVI. first, we see that 
the values of x are approximately the same, the molecular 
mass of the acid becoming less and less as it is more and 
more diluted with bexisene or toluene. It is remarkable 
that these two series of values for x fall out so nearly the 
same, for in the mixture of toluene and acetic acid the 
differences of their vapour tensions is so slight that the 
line of partial pressures of toluene is nearly horiaootal, 
and an error of one millimetre in the determination of the 
partial pressure may occasion an error of four units in the 
molecular concentration ; in the mixture of benxene and 



264 Vapour-tensions of Mixtures of Volatile Liquids. 

Acid, however, the error ftriting from this source is not t «;. A re-calculation of Resnau 
more than three-tenths of a unit, the angle made by the 
line of partial pressures being considerably greater than 
in the case of the other mixture. 

For the determination carried out at ao^ on the mixture 
of benzene and acetic acid, it is seen that the number of 
molecules of acid is less, and hence their molecular mass 
is greater than when the determinations were carried out 
at 35^ This is just what is to be expeded, for the 
lowering of temperature has been found to be invariably 
accompanied by an increase in the condensation of the 
molecule. 

I have sketched the curves corresponding to the values 
of m and x given in the foregoing tables in a system of 
co-ordinates with percentage composition as axis of ab- 
scissae and molecular masses as axis of ordinates. 

The curves for the mixture of acetic aeid and benzene 
at 35° pradically coincides with that of the mixture of 
acetic acid and toluene at 35^ while the curve for the 
mixture of benzene and acetic acid at 20° is parallel and 
slightly above the other two. The curves are perfeAly 
regular in form, and if prolonged to cut the right*hand 
axis of ordinates cannot give values varying by more than 
one unit ; accordingly it may be claimed that the point 
where the axis of ordinates is cut by the extrapolated 
curve gives to about one unit the molecular mass of acetic 
acid in the liquid state at the temperature taken for the 
determinations. The results of my extrapolations gives 
as the molecular mass of liquid acetic acid at 35^ 240, 
and at ao^ 244. 

It is interesting to compare these results with those 
obtained by Ramsay and Shields (** Ueber die Molekular- 
gewichte der Fliissigkeiten," Ziit,phys. Chem., xii., 470, 
1893). These investigators found by the determination 
of the superficial tension of acetic acid that its molecular 
mass between the temperature limits, 16^ and 46°, was 
equal to 217*2 (60 x 3 '6a) ; although this result leaves 
room for considerable uncertainty as to what the molecu- 
lar mass of the acid is at any given temperature between 
these limits, it is in corroboration of my results ; for, as 
has been well established, the degree of association in the 
molecules of a complex liquid is greater the lower the 
temperature, and my results pertain to temperatures which 
are lower or about the same as the mean of the two ex- 
treme temperatures given by the two English chemists. 

The method of determining the molecular masses of 
liquids described in this sedion is the only one as yet de- 
vised which permits of the determination at any given 
temperature of the mass of the molecule. 

It is founded on empirical results and depends upon no 
hypothesis other than the universally recognised one of 
Avogadro. It is applicable to all cases where the sub- 
stances under examination can be accurately analysed. 
It calls for no special apparatus, even a modest laboratory 
being provided with the necessary pieces. It requires no 
great amount of manipulative skill, and the results are 
obtained in relatively short time. I hope that it will be 
rigidlv tested by chemists, and any omissions of this mere 
sketch be supplied. 

Rtsumi, 

The main results of this article may be summed up as 
follows : — 

I. A method of determining the partial pressures of 
mixtures of liquids has been elaborated, and its sources 
of error discussed. 

a. Although the method can be said to give the vapour- 
tensions of pure liquids with an accuracy equal to that 
obtainable by the best of other methods only when the 
liquids are not very volatile, the results obtained by it 
for mixtures of liquids of not too different volatilities 
are accurate enough to serve as the experimental basis 
for theoretical deduAions and generalisations. 

3. A number of mixtures of representative liquids have 
been investigated as regards their vapour- tensions. 

4. In some cases extremely simple relations were found ; 
iu others, certain complexities presented themselves. 



fCnaiacaLKBWSy 
I Mot. 29. 1895. 

5. A re-calculation of Regnault*s determinations of the 
vapour-tensions of some mixtures of normal liquids, as 
well as a consideration of Raoult*s condusions and 
Brown's work on the boiling-points of solutions, showed 
that it was permissible to apply what was found true for 
any one temperature to any other. 

6. The relations between the concentrations in the 
gaseous and liquid phases were found to be quite simple 
and entirely in accordance With the provisions of the 
relations established by Planck and Nernst. 

7. The changes of temperature occurring when certain 
liquids were mixed were found to be very small, and the 
resulting mixtures were those which exhibited the simplest 
relations in their vapour-tensions. 

8. The vapour tensions of mixtures of acetic acid with 
benzene and with toluene were determined, and the re- 
sults were such as to permit of the determination of the 
molecular mass of the dissolved and liquid acid. 

9. A general method for the determination of the mole- 
cular masses of associated liquids at any given tempera- 
ture was developed and illustrated with acetic acid. 

The experimental part of this investigation was done 
in a laboratory in the School of Mines at Paris, placed 
at my disposition by the authorities of that noble institu- 
tion ; and I here take the pleasant privilege of thanking 
them for the courtesy thus extended to me. My cordial 
thanks are also due to M. Emilio Damour, Ing^nieur 
Civil des Mines, for his foreseeing kindness in furnishing 
me with apparatus and material; especially are my 
thanks due, however, to M. H. Le Chatelier, Inc6nieur 
en Chef des Mines, whose wise diredion and good 
counsel have been of great value to me throughout the 
work. 



PROCEEDINGS OF SOCIETIES. 

CHEMICAL SOCIETY. 
Ordinary M Siting ^ Novembtr yih^ 1895. 

Mr. A. G. Vernon Harcourt, President, in the Chair. 

Messrs. A. F. Fuerst, T. F. H. Gilbard, E. T. Read, and 
A. Stansfield were formally admitted Fellows of the 
Society. 

Certificates were read for the first time in favour of 
the Earl of Berkeley, Boars Hill, Abingdon; Messrs; 
Arthur Jenner Chapman, Burleigh House, Yerbury Road, 
Upper Holloway ; George Bertram Cockbum, B.A., St. 
George's Hospital, S.W.; Charles Croeker, St. Peter's 
Road, Cockett, Swansea; Gumey Cuthbertson, 69, 
Shoreham Street, Sheffield ; William Dixon, 102, Spring 
Street, Bury, Lanes. ; Patrick Joseph D. Fielding, 8, St. 
Joseph's Place, Cork; James Gardner, 80, Heaton Ter- 
race, Middleton, near Manchester; Edward Graham, 
B.Sc, Dalton Hall, Manchester; Edgar Septimus Hanes, 
X08, Alexandra Road, St. John's Wood, N.W. ; Thomas 
Hawkins Percy Heriot, 23, Wolseley Road, Crouch End, 
N.; Frederick Arthur Hillard, B.A., x, Upper Tichborne 
Street, Leicester ; Arthur Edward Holme, M.A., 3, Ash 
Terrace, Savile Town, Dewsbury ; Alfred James, 18, St. 
Andrew's Drive, PoUokshields, N.B.; Frederick Edward 
Johnson, 16, Stanley Terrace, West Park, Hull ; Leonard 
P. Kinnicutt, Ph.D., &c., Worcester, Mass., U.S.A.; 
Walter Mansfield, Trafalgar House, Broughton, Lanes. ; 
Cecil Massey, Lyndon House, Lenton Boulevard, Not« 
tingham; James McCreath, 4, Lombard Court, B.C.; 
David James Morgan, 10, Northampton Place, Swansea; 
Herbert Peck, Wigan Road, Ormskirk ; William Round, 
45, St. Peter's Road, Handsworth, Birmingham ; Clarence 
Arthur Seyler, B.Sc, 31, Windsor Terrace, Swansea; 
Matthew Smith, B.A., Aston Hall, Preston Brook. 
Cheshire ; Frank Robert Stephens, Idris and Co., Camden 
Town, N.W. ; George Stone, Sydney, N.S.W.; Albert 



CHBUtCAL NBW8,I 

Nov. 29, 1895. I 



New series of Hydrazines. 



265 



Thorpe, Cham wood Hoase, Sleaford Road, Preston ; John 
Willimms, B.A.. Wesley College, Sheffield; Thomas 
Rowland Wingfield, 43, Dorset Street, Bolton ; William 
Chattaway, Apothecaries Hall, Blackfriars, E.G. ; Martin 
Priest, Apothecaries Hall, Blackfriars, B.C.; William 
Oakes Kihble, Norton Villa, Buckhurst Hill, Essex. 

The Prbsidbnt announced that the following telegram 
had been sent to Madame Pasteur on the death of her 
husband, M. Louis Pasteur, in OAober last : — 

** Madame Pasteur, Institut Pasteur, Rue Dutot, Paris. 

"The Chemical Society of London, in common with 
the entire scientific world, mourns the loss of its illus- 
trious Foreign Member, and begs to express to you its 
deepest sympathy. 

"Vbrnon Harcourt, President, 

"T. E. Thorpe, Treasurer, 

"John M. Thomson, ] 

•• Wyndham R. Dunstan, [ Secretaries," 

" R. Mbloola, J 

and that the following Address had been presented on 

behalf of the Society by Dr. Frankland to the Institute of 

France on the occasion of its Hundredth Anniversary : — 

** The leading men of the French nation in Literature, 
Science, and Art celebrate to-day the hundredth anniver- 
sary of a great event. There had perished in the throes 
of the revolution a group of Academies which for more 
than a hundred 3rear8 had shed lustre upon France, and 
had contributed among the foremost to the general ad- 
vance of mankind. It was an eclipse of which the dark- 
ness could not last long. Two years later, on the 25th of 
OAober, 1795, the law was passed which revived the 
Academies and combined them in the Institute. 

** The Chemical Society of London, born half a century 
later, and representing one of the sciences which are 
united under the Academie des Sciences Matb^matiques 
et Physiques, desire on this occasion to record their sense 
of the splendid additions to chemical knowledge and 
thought which have been made by members of the 
French Academy. They respedfully offer to the Institute 
their congratulations on what has been achieved, to which 
they must now add their sympathy and regret for those 
who have passed away, thinking especially of the recent 
loss which science and humanity have sustained by the 
death of the illustrious Pasteur. 

** President, A. Vernon Harcourt- 

•• Treasurer, T. E. Thorpe. 

.. Honorary S....MW„.{ J-^^J^'.^^"-^^^^^^ 
'* Foreign Secretary, Raphael Meldola." 
October 25th, 1895. 

Of the following papeis those marked * were read : — 

*I20. **0n FUtme Temperatures and the Acetylene 
Theory of Luminosity. By Arthur Smxthellb, B.Sc. 

The author has submitted to experimental and critical 
examination the acetylene theory of luminous hydrocarbon 
flames advocated by Lewes {Trans, Chem, Soc, 1895, lxi*» 
32a ; Proc. Roy. Soc, 1895, ^vi*** 45o)t ^^^ concludes that 
it is untenable. 

Details of the measurement of the temperatures of dif- 
ferent parts of hydrocarbon flames by means of the Le 
Chatelier thermo-couple are given. It is shown that, to 
obtain readings of any value, the wires constituting the 
couple must m bent so as to fit the particular region of 
the flame in which the meaaurement is desired, and that 
if the sheet of flame be thin even this precaution is in- 
sufficient. The exploration of an ordinary flat coaUgas 
flame gives evidence of no sudden change of temperature 
in a vertical plane. Sudden changes are found, however, 
when the couple is moved from the middle of the flame 
outwards in a horizontal plane, and the mantle has a 
temperature higher than the melting>point of platinum. 

The author considers Lewes*s description of the distri- 
bntton of cones in flames to be based on erroneous tern* 



perature measurements, and finds no evidence of such a 
local condition of temperature as would point to the 
decomposition of acetylene. The conclusion in favour of 
the acetylene theory, based on the comparative luminosity 
of the ethylene and acetylene flames, is attributed to 
negled of the consideration that in the latter there is a 
higher temperature and a greater relative amount of 
carbon. The indired evidence derived from the behaviour 
of cyanogen is stated to arise from the yellow ammonia 
flame having been mistaken for one containing solid 
carbon. The theoretical arguments based on thermo- 
chemical considerations are adversely criticised. 

The author maintains that the luminosity of hydro* 
carbon flames, including the flame of acetylene, can be 
adequately explained on the older theory of their struc- 
ture confirmed and extended by his earlier experiments 
(Trans. Chem. Soc, 1892, Ixi., 2x7). According to this 
view, a luminous flame is invested by a sheath of gas in 
non-luminous combustion^ This sheath, which is double 
at the lower part, corresponds to the two cones of a 
Bunsen flame, and produces an exceedingly high temper- 
ature. The gas within this sheath is intensely heated as 
it ascends, and is gradually decomposed so as to furnish 
a sheet of carbon particles, becoming more and more nu- 
^merous. These glow partly by heat and partly by com- 
bustion ; the higher the temperature of the non-luminous 
sheath, and the greater the relative number of particles, 
the brighter will be the flame. This is well seen in the 
case of acetylene. The author believes that the precise 
steps in the decomposition of a hydrocarbon by which 
carbon is deposited are at present unascertainable by any 
dire^ means, but, as the glow of the carbon particles in 
a hydrocarbon flame is in no case greater than that ac« 
quired by a platinum wire immersed in the same region, 
he considers that there is no ground for supposing that 
the endothermic decomposition of acetylene (of which 
substance only a very small quantity has been found in 
the flame gases) plays any appreciable part in the 
phenome non. 

•121. **A New Series of Hydragines." By Frederick 
D. Chattaway and Harry Inolb, B.Sc. 

Primary and secondary hydrazines have proved such 
important substances that other substituted derivatives of 
hydrazine have scarcely been studied. 

Theoretically, hydrazine should yield five series of sub- 
stituted derivatives, of which only three are known, the 
primary, the secondary symmetrical, and the secondary 
unsymmetrical. No simple method of obtaining members 
of the other series has hitherto been described, and the 
authors have undertaken their investigation. 

The quaternary hydrazines, which are dealt with in the 
paper, can be obtained by a simple general readion from 
the secondary amines. 

The secondary amine is treated with sodium or sodium 
ethylate, whereby the hydrogen atom is replaced by 
sodium, RaNH-|-Na=RaNNa-|-H. The equivalent quan- 
tity of iodine is then allowed to aa upon the sodium 
compound, when the sodium atoms are withdrawn, and 
the two substituted amido-groups unite to form the 
quaternary hydrazine, — 

RaN-Na+Ia+Na-NRa=RaN-NRa+aNaL 
The aromatic quaternary hydrazines which have been 
so far more especially studied are stable well-crystallised 
compounds, which are not easily oxidised, and are 
scarcely, if at all, basic. Their percentage composition, 
and the molecular weights obtained by Raoult's method, 
using benzene as a solvent, agree well with the theo- 
retical. 

Tetraphenyl hydrazine, (C6H5)aN-N(C6H5)a, obtained 
by the above readion from diphenylamine, crystallises in 
long orthorhombic prisms, m. p. Z47^ It is easily soluble 
in benzene, chloroform, and acetone, and dissolves in 
cold concentrated sulphuric acid, giving a deep purple 
solution. 
Tetra-p-lolyl hydrazine, (C6H4CH3)aN-N(C6H4CH3)a, 



266 



Conshtution of Nitrososutphates. 



I CHsmcAL Nswg, 



prepared from di-^-tolylamine, crystallitee in large pale 
yellow monoclinic prisms or tables, m.p. Z38^ It is 
easily soluble in bensene, acetone, and chloroform, and 
dissolves in cold concentrated sulphuric acid, giving a 
brilliant asure-blue solution. 

122. " Tki Action of attain Acidic Oxidts on Salts of 
Hydroxy-acids. (Part II.). By G. G. Henderson, D.Sc, 
M.A., and David Prentice. 

The adion of antimonious and arsenious oxides upon 
salts of citric, malic, ladic, and mucic acids has been 
studied, and several new salts have been prepared, the 
oxide being heated with solutions of salts of those acids for 
varying periods, and the compounds formed precipitated 
by alcohol or separated by crystallisation. 

With citrates of potassium, sodium, and ammonium, 
antimonious oxide gave compounds of the general formula 
SbOM'3(C6H607)a*;rHaO, which are all crystalline and 
readily soluble in water. A sparingly soluble barium 
salt, SbOBa,(C6H607)3ioHaO, was obtained by precipi- 
tation, and from it a very soluble crystalline compound of 
the probable formula OH-Sb: (CcHyOyJa was prepared. 
Arsenious oxide gave similar compounds with citrates of 
the alkalis. They have the general formula - 
AsOM'3(C6H607)a'*HaO, 

are crystalline, and dissolve freely in water. 

Both antimonious and arsenious oxides dissolve in 
boiline aqueous solutions of alkaline malates. A well- 
crystallised antimony compound, whose simplest formula 
is (SbO)3K4H(C4H505)6*3HaO, was prepared, but no cor- 
responding arsenic compounds have yet been obtained, 
owmg to their instability. 

Boiling solutions of ladates of the alkalis and of 
barium readily dissolve both antimonious and arsenious 
oxides, and alcohol precipitates colourless syrups, con- 
taining large quantities of unaltered ladates. 

Compounds of the oxides with mucates were also pre- 
pared, though with some difficulty. Two antimony 
compounds of the formulae — 

2SbOKC6H80rKC6Hg08-6HaO and SbOKC6H808-4HaO 
were obtained in the form of sparingly soluble crystalline 
powders. An arsenic compound corresponding to the 
second of these was likewise obtained. 

These substances might be regarded as double citrates, 
malates, &c., containing the radicles (SbO)' and (AsO)', 
but, if so, then in all probability those radicles replace 
the hydrogen of alcoholic hydroxyl groups, and not the 
hydrogen of carboxyl groups as in the formation of salts, 
for otherwise it is difficult to undertsand why hydroxy- 
acids alone seem to have the power of forming such 
compoonds. On the other hand, they might be regarded 
as salts of acids derived from antimonious or arsenious 
acids by replacement of two of the hydroxyl groups of 
those acids by organic acid radicles, as is the case with 
the ^antimonio- and arsenio-tartrates. The formulas of 
such acids would be, for antimonio-citric acid — 

GHSbrCCfiHyOyja, 
for antimonio-malic acid GH'Sb : (CiH505)a, for anti- 
monio-mucic acid GH-Sb : CfiHsOs ; the formulas of the 
arsenious acid derivatives would be similar to these. In 
the case of some at least of the new compounds this view 
appears preferable. 

123. ** Sodium Nitrososuiphati:' By E. Divers 
F.R.S., and T. Haga. , ui , ^ 

Sodium nitrososulphate, being a very soluble salt, does 
not crystallise out when even the strongest solution of 
sodium sulphite is treated with nitric oxide. But if the 
solution, after this treatment has been continued long 
enough, be deprived of most of its sodium sulphate by 
freesing out, and be then evaporated in a vacuum to a 
very small volume, sodium nitrososulphate is deposited 
in crystals. , 

It is an anhydrous salt, forming very minute crystals, 
which in the tolation adhere together in opaqoe cnitU. 



The salt is slightly alkaline to litmus, and tastes veiy 
much like common salt. It is exceedingly soluble in 
water and very unstable, wet or dry. In the dry state, 
in which it can be obtained in a desiccator, and at the 
common temperature, it rapidly decomposes 00 exposure 
to (damp) air, becomes nearly as hot as slaking lime, 
and gives off Ivge quantities of nitrous and nitric oxides. 
The residue consists of sodium sulphate and sulphite. It 
thus behaves at the common temperature as potassium 
nitrososulphate only does when heated to about loo^ 

In solution in water it continuously decomposes, like 
the potassium salt, into sulphate and nitrous oxide. A 
little sodium hydroxide greatly retards this decomposition 
in water, but if a solution of the salt containing sodium 
hydroxide is heated to boiling, the salt decomposes freely 
into nitric oxide and sulphite. This behaviour is unlike 
that of the potassium salt. 

Its composition, which was indiredly determined quan- 
titatively, is Na*GN:N0'S03Na. 

124. ** The Constitution of Nitrososulphaiis,** By E. 
Divers, F.R.S., and T. Haga. 

Potassium nitrososulphate in aqueous solution becomes 
strongly alkaline when mixed with a little alcohol. This 
is due to the salt and the alcohol partly decomposing into 
potassium ethyl sulphate, nitrous oxide, and potassium 
hydroxide. The primary readion is, beyond a doubt, one 
in which potassium hydrogen hyponitrite is produced, 
along with the potassium ethyl sulphate, although none 
can be deteded ; but then its formation proceeds here 
very slowly, and certainly not faster than it is known to 
decompose of itself into potassium hydroxide and nitrons 
oxide. 

This readion is peculiarly interesting, for in it alcohol 
decomposes a sulphate in alkaline solution, and liberates 
potassium hydroxide, though indiredtly. The occurrence 
of this readion, taken with other properties, solves the 
problem of the constitution of the nitrososulphatea. They 
are an hydro-double salts of hyponitrous and sulphuric 
acids, which hydrolyse into the acid salts of these 
acids, the acid salts simultaneously changing into normal 
sulphate, nitrous oxide, and water. They are analogous 
to the thiosulphates, the hyponitrite radicle ading as sul- 
phur does in them. Thus we see calcium thioaolphate 
and sodium nitrososulphate forming themselves from the 
sulphite of their metal and decomposing into it again, 
under precisely similar conditions. Nitrososulphates are, 
however, true sulphates, as their readions with alcohol 
and with acidified barium chloride show, their nitrogen 
being united to their sulphur only though an atom of oxy- 
gen, KGNa'0*S03K. 

(To be continued). 



PHYSICAL SGCIBTY. 
Special Meetings November 22Hd, 1895. 

Captain W. db W. Abnbv, President, in the Chair. 

The following resolution with reference to the Articles 

of Association was passed : — 

** In Article 33 to strike out the words * by the pay- 
ment of £10 in one sum,' and in place of this to insert 
the words * the composition fee shall be for every 
member who shall not have paid ten annual subscrip- 
tions, fifteen times the amount of the annual subscrip- 
tion payable by such member ; and for any member who 
shall have already paid ten or more annual subscrip- 
tions, ten times the amount of the annual subscription 
payable by such member.* *' 

The Grdinary Meeting then took place. 

Dr. G. Johnstone Stonby exhibited a Print of Profs. 
Runge and Pascheo's Photograph of the Spedrum of the 
Gas obtained from Cl^veite, together with a Diagram 



CaBMICALNtWlyl 

Nov. 29, 1895. I 



Direct-reading Platinum Thermometer. 



267 



illustrating the Manner in which these Observers have 
arranged all the Lines obtained in two Sets, each Set 
containing Three Series of Lines. 

Dr. Stoney also drew attention to the resemblance be- 
tween each of these sets of three series of lines and the 
similar triple series obtained in the case of the metals of 
Mendeleeff s first group. The lines of the different series 
in the case of the gas obtained from cl^veite have certain 
definite peculiarities, which permit of their identification 
and seledion. The two gases, to the presence of which 
the two sets of lines are presumably due, can be partly 
separated by diffusion through a plug of asbestos. Prof. 
Ramsay's observation that by suitably altering the pres- 
sure of the gas the predominance of the lines in either 
of the two sets can bie increased is, however, against the 
theory that the two gases are really separated by dififusion. 

Three of the original negatives taken by Prof. Rowland 
when preparing his map of the solar spedruro were also 
exhibited. 

Dr. Gladstone said he had examined the spedrum of 
the gas in two tubes, one of which had been filled by dif- 
fusion through an asbestos plug, and the helium line (Dj) 
was certainly brighter in one tube than in the other, 
though the brightness of the remaining lines appeared 
about the same in both tubes. As to the difficulty of 
allocating the new gases in MendeleefiPs table, it ap- 
peared to him (Dr. Gladstone) that they would have to 
be put in the first group, between hydrogen and lithium. 
An examination of the successive differences between 
adjacent members of the metals in the first group showed 
that these differences increased as we go downward. If, 
then, the new gases have atomic weights of, say, a 
and 4, we should have for these differences 2, a, 3, 16, 
z6, 26, &c., instead of 6, z6, 16, &c., as at present. The 
important point which required investigation was whether 
these two gases were really simple bodies or not. 

Prof. SiLVANUS Thompson asked if Runge and Paschen 
had performed a similar analysis of the lines in the 
spe^a of other elements besides the members of the first 
group. He would also like to know if, in the case of 
any element besides hydrogen, the lines could be arranged 
in a single series. 

Dr. Stonby, in reply, said that the spedra of most of 
the metals had been analysed ; the chief exceptions being 
iron, nickel, cobalt, and manganese. There was no 
other element besides hydrogen which gave a single series 
of lines. 

Prof. Herschbl gave an account of a line of reasoning 
which had led him many years ago to a formula resem- 
bling that expressing Balmer's law for the hydrogen lines, 
namely, — 

i - I - ^ . 
A n« 

The Chairman (Captain Abnby) drew attention to the 
fad that Runge expressed his results to t»*»9^^ of an 
Angstrom unit, although Dr. Stoney had said the measure- 
ments could only be made to within ^gth of a unit. There 
was great lack of uniformity in the method of drawing 
speAra in general ose; he strongly recommended the 
placing of the red end of the spedrum to the right, so 
that the wave-lengths increased from left to right. As to 
the three series of lines obtained in the case of most ele- 
ments, it was not conclusiveljr proved that they were not 
due in each case to three distind kinds of molecules, and 
it will probably be found that there are more than two 
simple gases present in the gas evolved from d^veite. 

Mr. R. Applbyard read a ** Nott on tk$ Action of SuU 
phur Vapour on Copptr:* 

When a copper wire is exposed for some time to the 
adion of sulphur vapour it becomes entirely converted to 
snlpbide of copper, and it is found that there is a fine 
axial hole running down the rod of sulphide formed. 
Rods of copper of square sedion, cut from a block of 
copper after exposure to the adion of sulphur vapour, also 



exhibited the axial hole, the rod of sulphide formed being 
of circular cross-sedion. In every case the diameter of 
the rod of sulphide formed is about twice that of the 
original rod of copper. Delta metal was found to be un- 
aded upon by the sulphur vapour. 

Mr. Applbyard then read a paper on **A y Direct' 
rtading ' Platinum Thtrmomttsr,** 

This form of platinum thermometer has been devised 
with the view of determining the temperature of the di- 
eledrics employed in some experiments on the variation 
of the eledrical resistance of dieledrics with temperature. 
The thermometers consist of six platinum coils, each of 
about 7 ohms resistance, attached to thick copper leads. 
A slide-wire Wheatstone*s bridge is employed to measure 
the resistance. The stretched wire is 3 metres lone, and 
the moving contad so arranged that it is impossible to 
damage the wire. The auxiliary coils used in connedion 
with the bridge are immersed in a bath of paraffin oil, 
the temperature of which is maintained constant, and a 
little above that of the air, by means of a glow-lamp im- 
mersed in the oil. 

Mr. Applbyard also read ** A Historical Note on 
Resistance and its Change with Temperature,** 

He showed that the earliest measurements of the 
variation of resistance with temperature were made by 
Lenta in 1833. Some experiments on this subjed made 
by Davy were also referred to, and some of these experi- 
ments repeated before the Society. 

Mr. Trotter said he agreed with the author that the 
" reserve of precision ** at our disposal, on account of the 
delicacy of some of our modem instruments, ought to be 
made use of to facilitate the rapid performance of many 
measurements where the utmost accuracy is not neces* 
sary. He had the impression that platinum silver was 
not now considered the best material for use as the bridge 
wire. 

Mr. H. F. BuRSTALL explained the differences between 
the temperature as measured on the mercury, air, and 
platinum thermometers. At a temperature of about 40* 
the platinum thermometer read about 0*4% and the mer- 
cury thermometer about 0*1* below the air thermometer. 
Prof. Callendar had obtained measurements of tempera- 
ture corred to within 0*1° by using a Weston voltmeter 
and an ordinary Wheatstone bridge; the variations of 
resistance, and hence the temperature, being read diredly 
from the defledions on the voltmeter. 

Mr. Rhodbs thought that, except where extreme accu- 
racy was necessary, the mercury thermometer was very 
much more convenient than the platinum thermometer. 

Mr. BuRSTALL said the great convenience of the 
platinum thermometer lay in the fad that the scale could 
be read at a distance of many yards from the point where 
the temperature was being measured, and hence could 
be used in many places where it would be impossible to 
read a mercury thermometer. 

Mr. Blakbslby considered that the author was some- 
what bold to state that for general purposes it was never 
necessary to measure temperature to nearer than one- 
tenth of a degree. 

The author having replied, the Society adjourned till 
December 13th. 



Appointment.— Mr. W. Lincolne Sutton, A.I.C., hat 
been appointed Public Analyst for the city of Norwich. 

Pasteur's Successors. — According to the Chemiker 
Zeitung a dispute has arisen in the Pasteur Institute as 
to the succession to the presidency of this establishment, 
Duclaux or Roux. Duclaux ranks high in the scientific 
world, whilst Roux figures as a physician. The Council 
of the Institute finally decided in favour of Duclaux, 
whilst Roux is appointed Second Diredor. It is not 
generally known that Pasteur, in addition to his scientific 
eminence, was distinguished as a financier. 



268 Production of Citric A cid by the Oxidation of Cane-sugar. { ""C:^ ?5^ 



NOTICES OF BOOKS. 



A TrMtisi on thi Manufacture of Soap and CandUs, 
Lubricants^ and Glycerin, By Wm. Lant Carpenter, 
B.A., B.Sc., F.C.S., &c. Second Edition, Revised 
and Enlarged by Henry Lbask. London: E. and 
F. N. Spon. New York: Spon and Chamberlain. 
1895. Crown 8vo., pp. 446. 

It is satisfaAor^ to find that this work has not under- 
gone any detenoration from the regretted death of its 
author. The second edition, now before us, has been 
entrusted to Mr. Henry Leask, a recognised authority on 
paraffin refining and on the manufadure of candles. 

In the first chapter we are rightly told that though soap 
was in use prior to the Christian Era, yet the modern 
development of the soap manufadure dates only from the 
early part of the present century, and is substantially due 
to two French inventors, Chevreul and Leblanc. 

We regret the recent decline in the consumption of 
palm-oil, since in vegetable fats we are substantially safe 
from the presence of the morbid produAs of microscopic 
life. The author refers to the liability of cocoanut-oil and 
palm-oil to turn rancid. We once knew of a cask of the 
latter oil reaching the consumer, in Yorkshire, perfedly 
free from rancidity. This was pradically no advantage, 
since the greater part was eaten by the workmen. Con- 
cerning linseed oil, the author mentions a fraud pradised 
in the Russian ports, viz., the addition of 1 measure of 
hemp seed to every 39, or latterly 19, measures of linseed. 
In India the oil seeds are often grown promiscuously. 
Indeed to obtain absolutely pure oils for any scientinc 
purpose is a difficult and doubtful matter. 

The vegetable tallows, the produds of species of 
Hopea, and of Stillingia saUfera, are found, as lubricants, 
superior even to olive oil. 

The following remark is gravely significant : — *' The 
soap-pan appears to be the natural destination of any 
rough fat-containing matter which can be turned to no 
other purpose." 

It is interesting that laree quantities of Fuller's earth 
are yet exported from this country to America to 
serve in the purification of lard. The bleaching of oils 
and fats still ofiFers scope to the inventor, since many 
agents which decolourise at the same time promote 
rancidity. 

The problem of recoverin|r glycerin from spent lyes is 
rightly pronounced very difficult, and it is regarded as 
probable that in the future all glycerin will be obtained 
diredly from fats prior to saponification. 

The difficulty of corred sampling solid and semi-solid 
fats is insisted upon. The identification of oils in mix- 
tures — and there are few samples which may not be re- 
garded as mixtures — is discussed at some length. The 
spedroscope assists us only in some cases. Maumen^'s 
test, according to Allen, sometimes gives unaccountable 
results. 

When soap-makers manufadure their own alkali, their 
operations are much complicated, and require more plant 
and space ; hence whether such causticising is economical 
or not must depend on local conditions. The Solvay 
alkali process will not, it is considered, commend itself 
to the adoption of soap-boilers, though the ammonia-soda 
is excellent. It is to be regretted that in the English 
alkali trade the false atomic weight 24 is still used instead 
of 23, the corred figure. We may here regret the 
countenance given to Baum6*B hydrometer in this work, 
though two pages are given up to its inconsistencies (pp. 
278 and 279). 

The common opinion that a soap-work is necessarily a 
public nuisance is totally erroneous. Such an establish- 
ment, if well-conduded, is far less offensive than, tf.^., 
a fried-fish shop. 

Space will not allow us to extend our notice of thU 
book to the remaining portions, which treat of lubricants 



and of the manufadure of candles. Upon the whole, 
this second edition may be regarded as an improvement 
upon its predecessor. It will be found a useful manual 
by the student of those departments of technical chemis- 
try which discuss the applications of the oils and fats. 



Perken, Son, and RaymenVs Illustrated Catalogue of 

Photographic Apparatus, Magic Lanterns, and Optical 

Instruments : contains numerous Redudions in Prices, 

many Novelties, and Fresh Matter. '* Optimus,*' 99, 

Hatton Garden, Holbom Viadud, and 141, Oxford 

Street, W., London. 

The photographer, be he professional or amateur, will 

find here ample scope for choice of cameras and all other 

fittings and accessories. The lanterns shown are a great 

convenience for scientific ledurers, as well as for their 

hearers. 

The old "sketching ledure," in which an awkward 
representation of apparatus, of specimens, or dissediona, 
was given by dint of chalk and black-board, is evidently 
and deservedly fading into the ** infinite aaure,'* whilst 
the ledurer can, by means of the lantern and of appro- 
priate slides, give a far clearer and more accurate view of 
the objeds to be explained. 

The catalogue before us gives a wonderful assortment 
of slides, suitable for illustrating all kinds of ledures, 
astronomical, historical, geological, antiquarian, biologi- 
cal, and miscellaneous. 

In this catalogue, as we believe in all others issued by 
opticians, we notice that the spedroscope does not figure 
prominently, if at all. This is a proof that an instrument 
so necessazy for research in various sciences is very rarely* 
as yet, in demand by investigators. 



CORRESPONDENCE, 

PRODUCTION OF CITRIC ACID BY THE 
OXIDATION OF CANE-SUGAR. 

To the Editor of the Chemical News, 
Sir, — We certainly ** profess to have repeated" Dr. 
Phipson's experiments, and have taken care to follow hia 
instrudions implicitly. We fail to see why he should 
state that we have not done so. 

Dr. Phipson now says that the produds of oxidation of 
cane-sugar by permanganate vary considerably, ** accord- 
ing to the respedive quantities of permanganic acid and 
sugar, according as sulphuric acid or nitric acid is used, 
and according to the temperature of the day." We have 
employed the reagents in the proportions Dr. Phipson 
recommended, and have failed to produce any citric acid, 
as we also did on previous occasions when we used our 
own discretion as to the proportions of the materials. 

If Dr. Phipson will tell us any better way of recof*- 
nising citric acid in a liquid also containing tartaric acid, 
saccharic acid, and formic acid, than that based on the 
precipitation of calcium citrate by boiling a neutral solu- 
tion, we shall be glad to try his process. We confess 
that we do not know any better plan. 

Dr. Phipson, in conclusion, asks us what becomes of 
the sugar, if saccharic acid, tartaric acid, formic acid, and 
citric acid are not formed. Saccharic acid is well known 
to be a produd of the oxidation of cane-sugar, and tartaric 
acid, we have reason to believe, can be obtained under 
suitable conditions. The question of formic acid is open. 
It is for Dr. Phipson to prove that citric acid is formed, 
as asserted by him, and to prescribe a method by which 
other chemists can repeat his experiments successfully. — 
We are, &c., 

Alfrbd B. Sbarlb, 
Arnold R. Tankard. 

, 67, Surrey Street, Sheffield* 
November 23, 189s • 



Chbiiical Nbws, I 
Nov. 29, 1895. I 



Chemical Notices from Foreign Sources. 



269 



CHEMICAL EDUCATION. 

To ihi Editor of the Chunical News. 
SiRt— In your *' Address to Students " in the number last 
to hand (Chemical News, vol. Izxii., p. ixz), you refer 
to the chemical education obtainable and appreciated, 
and therefore paid for, in Germany. I have seen the 
same matter often written of for some years, and the want 
of progress in chemical industries in Great Britain 
ascribed to the want of appreciation of such trained skill, 
by British manufaAurers. It is always advantageous to 
trace things to their first cause ; and I think that in this 
case it may be found in a remark made to me in the early 
sixties by Dr. £. Ronalds, then in Edinburgh. I had 
formerly been hit assistant, he being managing partner in 
the Bonnington Chemical Works, where the tar from 
Edinburgh and Leith was treated, and I made some 
mauve from aniline in a fradionated series of coal-tar 
bases shortly after Perkins patented his process — about 
1857, I think — and on the occasion referred to, whilst 
speaking of the coal-tar colours, he said :— '* The Excise 
will drive the business out of the country, so there is no 
use touching it." 

Adually this is what has happened, as the Government 
by the duty on alcohol, and the rigorous regulations as to 
its use, have driven a trade worth £20,000,000 per annum 
out of Great Britain. For the greater part of the thirty- 
eight years since the industry began, the greater portion 
of the raw material was provided by the United Kingdom, 
and all the first colours were discovered and made there, 
showing that the chemical knowledge was there. The 
nse of free alcohol then transferred the manufadure to 
Germany. The manufadurer demanded technical 
chemists ; and technical chemical schools arose, not only 
supplying the demand, but leaving a surplus of trained 
men which has overflowed into every branch of chemical 
industry. And now the supply of the raw material for 
that manufadure is curtailed to the United Kingdom, in 
consequence of German improvements in coke making, 
80 that beosine, which used to be 15/- per gallon, is 
now i/-. 

In the first half of this century the great strides in in- 
dustrial chemistry were made in bleaching and light pro- 
dudion, and that in the United Kingdom ; and that as the 
Government did not interfere with them they took root 
and flourished. In the second half of the century, the 
great stride has been in colours ; but here the Government 
insisted on its pound of flesh, so this industry fled, and, 
in consequence, other British chemical manufadures are 
threatened. 

To support technical schools there must be a demand 
for those trained in them, and good positions in view ; and 
this can only come from a rapidly growing industry in 
which a few have drawn prizes and hundreds think they 
may do the same. Other industries which have arrived 
at the rule-of-thumb stage are benefited only indiredly, 
and it must be remembered that what is the highly scien- 
tific to-day becomes the rule-of-thumb of a few years 
hence.— I am, &c., 

W. A. D. 

Sydney, OAober az, x89S* 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

KoTi.— All degrees of temperature are Centigrade anleis otberwiie 
tipreued. 

Comptes Rmdus Hebdomadaires des Siances, de VAcadtmie 
des Scietues, Vol. cxxi., No. 19, November 4, 1895. 

AdtioD of Silicon upon Iron, Chromium, and Stiver. 
— H. Moissan. — This paper will t>e inserted in full. 

Spe(5tral Researches on the Star Ahmir (a-Aquilae). 
— H. Deslandres. — The bulk of this memoir is purely 



astronomical, but it may be here mentioned that, unlike 
the other white stars, Altair has iron and calcium rays 
almost as broad as the rays of hydrogen. They have 
been deteded on seeking for, among the broad black rays 
of the spedrum, the small brilliant reversed rays which 
constitute the bulk of the atmospheric spedrum. 

Treatment of the Emerald and the Preparation of 
Pure Glucina.— P. Lebeau.— This memoir will be in- 
serted in full. 

On m Group of Mineral Waters containing Am- 
monia; Bituminous Waters.— F. Parmentier.^ The 
waters in question are obtained from springs in the 
neighbourhood of Clermont. Ammonia can be deteded 
in them by means of the Nessler reagent. Beyond bitu- 
minous matter, recognisable by the smell and taste, there 
is no other organic matter. 

Determination of Tannin in Wines.— E. Manceau. 
— The author's method is as follows : — About 100 c.c. of 
wine are placed in a small flask with a ground glass 
stopper, and i grm. of gut-string. In a week, at about 
15^ all the tannin will have been taken up. He then 
titrates with a solution of permanganate, x c.c. of which 
corresponds to 0*2 m.grm. of pure ^allo-tannin, using as 
indicator a sulphuric solution of indigotin. The difference 
of the volumes of permanganate taken to decolourise 25 
C.C. of the original wine and 25 c.c. of the same wine de- 
prived of tannin shows the weight of gallotannin corre- 
sponding to 25 c.c. of the wine. To prepare the gut- 
strings, violin strings (not oiled) are submitted in succes- 
sion to prolonged washing in alcoholised water, acidulated 
water, and pure water, until they no longer yielded to 
these solvents any substance capable of reducing perman- 
ganate in the cold. 

Adtion of Chlorine upon Normal Propylic Alcohol. 
— ^Andr^ Brochet. — The author has made an especial 
Btudy of a-chloropropionic aldehyd and of chlorodipro- 
pylicpropional. 

Ozotoluene. — Adolphe Renard. — If pure toluene is 
submitted to the adion of ozone, there is formed an ex- 
plosive produd, ozotoluene, analogous to ozobenzene. It 
forms a white translucent mass, of a gelatinous asped. It 
decomposes at from 8** to zo^ Its composition is prob- 
ably C7H8O6, whence it is the higher homologue of ozo- 
benzene, CeHeOfi. With pure xylene (ortho-xylene) sub- 
mitted to ozone at 0° there is also obtained a white ex- 
plosive produd. 

Study of the Nitration of Menthone.— M. Konava- 
loff. — The author has obtained a produd of the composi- 
tion Cx6Hx7(NOa)0. 

Fermentation of Cellulose.— V. Omelianski.- This 
phenomenon has generally been ascribed to the adion of 
Bacillus amylobaettr. This organism the author regards 
as a ** colledive species." The pure bacillus he considers 
to be slender, consisting of straight and sinuous joints, 
from 6 to 7 /A in length and 02 to 0*3 /a in breadth. It 
forms regular round spores. 

Bxperiments on the Direct Production of Pure 
Ethylic Alcohol by the Fermentation of Asphodelus 
ramosus and Scilla maritimm by the Aid of Pure 
Wine Ferments.— G. Riviere and M. Bailhache.— The 
nature of this paper appears sufficiently from the title. 

Bulletin de la Societe d* Encouragement pour PIndmtrie 
Nalionale. Series 4, V^l. x.. No. 117. 

The Expansion of Glass, and on Soldered Glasses. 
— A Report presented by Dr. Schott. — For siliceous 
glasses the expansion increases with the proportion of 
alkali. Boric acid produces a striking decrease of expan- 
sion. In superposing upon each other two glasses of dif- 
ferent compositions, it is requisite that there should exist 
a certain relation between tne relative thickness of the 
two layers of glass and their coefficients of expansion. 
Thus at Jena they solder normal thermometer glass, the 



270 



Chemical Notices from Foreign Sources. 



f Cbsmical Niwb, 
1 Hov. 29. 189s- 



coefficient of cubic expansion of which between o^ and 
xoo°siO*ooooa44, to an aluminous sodium borosilicate the 1 
expansion of which es 0*0000177. The former kind of 
glass must be placed externally and the second internally 
in order to form a hollow vessel or a tube. We may also 
join together three or more layers of two or more glasses. 
Of two layers of glass with different expansions, after 
cooling, that with Qit greatest expansion will be in a state 
of tension, and the other in a state of compression. Ex- 
ternal layers in a state of compression increase in a 
striking manner the resistance of glass to mechanical 
adions and to rapid changes of temperature. Flasks thus 
manufadured may be strongly heated (to a temperature 
of 184°), and may then be sprinkled with cold water with- 
out injury. Such glasses are not liable to the sudden 
rupture presented by glass tempered by the process of 
De la Bastie« 

MEETINGS FOR THE WEEK. 

MoNDAT, and.— Society of Aitt, 8. ** Mechanical Road Carriages," 
by H. Worby Beaamoat, M. Init.C.E. (Oaator 
LeAarei). 
— Society of Chemical Industry, 8. ** Alkali Manufac- 

ture by the Hargreavet Bird System of Eledtro- 
lysis/by Mr. J. Hargeavcs, F.C S. •' The Ana- 
lysis of Chrome Iron Ore, Perrichrome, and 
Chrome Steel," by Dr. S. Rideal and Mr. S. 
Rosenblum. 
— — Royal Institution, 5. General Monthly Meeting. 

Wbombsdat, 4th.— Society of Arts, 8. " Mural Painting, with the 
Aid of MeUllic Oxides and Soluble Silicates," 
by Mrs. Anna Lea-Merritt and Prof. W. C 
Roberts-Austen, C.B., F.R.S. 
Thursday, sth«~Chemical, 8. " The Constitution of Terpenes,'* 
by Prof. Armstrong, F,R.S. ** New Denvatives 
from a-Dibromo-camphor," by M. O. Forster. 
"The Chemistry of Dibromopropylthiocarbimide, 
and the Action of Bromine and Iodine on Allyl- 
thionrea," by Prof. A. E. Dixon. Ballot for the 
EleAion of rellows. 

NOTICE. 

JOHN CLIFF& SONS, Exchange Chambers, 
LiBOS, wish to SELL (preferred) or LET their Chemical 
Stoneware and Pipe Pottery, at Runcorn, upon Manchester Ship 
Canal (and scheduled for purchase), with view of OPENING AT 
LEEDS, near their headquarters. 

Either Trade Plant or Works separate if desired. Part can re- 
main on Mortgage. In Chemical trade centre, and next door to 
larg e ChemicalWorks. 

Telepbone 
No. aa4b 

P. WIGGINS ft SONS, |;i;^iTnSr""l'f;c* Lon^oi.. 

MICA MERCHANTS, 

UanufactUTtri 0/ Utca Goods for EUctncai and ALL p^tpoui 

Contractore to Her Maiesty'sOovernment 



MICA 



rater-Glass, or Soluble Silicates ot boaa 

and Potash, 10 large or small quantities, and sither soiid 
or in solution, at ROBERT RUMNEY'S. Ardwick Cbemicsl 
Works. Mancoester. 



w« 



JUST PUBLISHED. 
446 Paget and 104 lUustraiiont, Price 12s. &<• 

A TREATISE ON THE MANUFACTURE 

SOAP AND 'candles, 

LUBRICANTS, AND GLYCERIN. 

By WM. LANT CARPENTER, B.S0. 
Second Edition, Revited and Enlarged by HENRY LEASK. 

CONTENTS. 

Historical Epitome and Re erences. Theoretical Principles. 

Raw Materials : Their Sources and Preparation. 

Raw Materials : Refining, Clarifying, and Bleaching. 

Raw Materials : Their Proximate Analysis. 

Caustic Alkali and other Mineral Salts. 

Manutaaure ol Household Soaps : The Process of Saponification. 

Treatment of Soap after its Removal from the Soap Copper: Cooltngt 
Cuttini^, Drywg, Moulding. 

Soap— Filling and Sophisticating. 

Special Soaps : Household, Laundry, Floating, Disinfeaant, Hard- 
water, Sand, Cold-water. Powders, Manaf«anrers', ToUct* 
Transparent, Fancy, Solidified, Glvcerin, &c. 

Theory of the Aftion of Soap— Its Valuation and Ajialysis— Distri- 
butioo and Position of the Trade. 

Lubricating Oils, Railway and Waggon Grease, ftc. 

Candles— Raw Materials, their Sources and Preliminary Treatment. 

Processes for the Conversion of Neutral Pats into Patty Adds— The 
Manufadture of Commercial Stearin. 

The Manufaaure of Candles and Night-lights— Their Value aa lUa- 
minanu. Glycerin. Bibliography. Index. 

B. ft F. N. SPON, zas, Strand, London. 
FOREIGN SCIENTIFIC BOOKS. 

IMPORTERS OF FOREIGN BOOKS, 

Receive regularly all Foreign Scientific Books. 

Catalogues and lists post free on application. 

14, Hbnribtta Strbbt, Covbmt Qardbn, London; 

20, South Frbdbriok Strbbt, Edimbueoh ; 

and 7, Broad Strbbt, Oxford. 

OLD PLATINUM 

In any form Purchasbd for Cash. 

Highest prices allowed by 
ROBERT PRINGLB & CO., Gold and Silver 
Reiin^rs, &c., 40 and 42, Clerkenwell Rd., B.C. 

Send for Price List. 
Hhctographic Residues reduced and purchased. 

SULPHUROUS ACID. 

SULPHITES AND BISULPHITE OF LIME, SODA, &c 

HYDROGEN PEROXIDE, 10/30 vols. 

CARAMELS, Liquid and SoUd. 

BENNEU d JENNER, Stratford, London. 




J-TJST IPTJBIilSHIEID- I=»S.IOE £± 58. 



A HANDBOOK OP 

INDUSTRIAL ORGANIC CHEMISTRY 

Adapted for the use of Manufacturers, Chemists, and all Interested In the Utilisation of 
Organlo Materials In the Industrial Arts, 

By SAMUEL P. SADTLER, Ph.D., F.C.S. 

SECOND REVISED AND ENLARGED EDITION. 

Pp. 637. With 127 Illustrations. 

London : J. B. LIPPINCOTT COMPANY, 10, Henrietta St., Covent Garden. 



CbBMICAL NBWtt I 

Dec. 6, 1895. I 



New Gases obtained from Uraninite. 



THE CHEMICAL NEWS 



Vol. LXXII., No. 1880. 



ON THB 

NEW GASES OBTAINED FROM URANINITE.* 
(Sixth Note). 

By J. NORMAN LOCKYER, C.B., F.R.S. 

As Mr. Crookes has now pablished (Chemical News, 
vol. Ixxii., p. 87) the wave-lengths of the lines in the 
spedra of the new mineral gases observed by him in the 
tabes supplied by Professor Ramsay, I propose in the 
present paper to bring together some notes I have made 
^ (some of them some time ago) on the same subjed. 

The researches made at Kensington in connexion with 
the new gases obtained from brdggerite and other 
minerals has consisted, to a large extent, of comparisons 
, of the lines in their speAra with lines in the spedra of 
the sun and stars. Preliminary accounts of these com- 
parisons have already been given, and they show that the 
bright yellow line seen in the gas from brdggerite is by 
00 means the only important one which appears. 

Although the general distribution and intensities of the 
lines in the gases from brdggerite and cliveite sufficiently 
corresponded with some of the chief ** unknown lines '* 
in the solar chromosphere and some of the stars to render 
f identity probable, it was desirable to see how far the con- 
clusion is sustained by detailed investigations of the wave- 
lengths of the various lines. 

TA# Yellow Line X 5875*9. — Immediately on receiving 
from Professor Ramsay, on March 28th, a small bulb of 
the gas obtained from cliveite, a provisional determina* 
tion of wave-length was made by Mr. Fowler and myself, 
in the absence of the sun, by micrometric comparisons 
with the D lines of sodium, the resulting wave length 
' being 5876*07 on Rowland's scale. It was at once 
apparent, therefore, that the gas line was not far re- 
moved from the chromospheric D3, the wave-length of 
which is eiven by Rowland as 5875*98. 

The bulb being too much blackened by sparking to give 
sufficient luminosity for further measurements, I set 
ftbout preparing some of the gas for myself by heating 
brdggerite tn vacuo, in the manner I have already de- 
scribed. A new measurement was thus secured on 
March 30 with a spe^oscope having a dense Jena glass 
prism of 60^ ; this gave the wave-length 5876*0. 

On April 5th, I attempted to make a direa comparison 
with the chromospheric line, but though the lines were 
shown to be excessively near to each other, the observa- 
tions were not regarded as final. 

Proiiessor Ramsav having been kind enough to furnish 
me, on May x, with a vacuum tube which showed the 
yellow line very brilliantly, a further comparison with the 
chromosphere was made on May a. The observations 
were made by Mr. Fowler, in the third order speArum of 
a grating having 14438 lines to the inch, and the observing 
telescope was fitted with a high-power micrometer 
eye-piece ; the dispersion was sufficient to easily show the 
difference of position of the D3 line on the east and west 
limbs, due to the sun's rotation. Observations of the 
chromosphere were therefore confined to the poles. 

During the short time that the tube retained its great 
brilliancy, a faint line, a little less refrangible than the 
bright yellow one, and making a close double with 
it, was readily seen, but afterwards a sudden change took 

Elace, and the lines almost faded away. While the gas 
ne was brilliant, it was found to be ** the least trace more 



* A Paper read before the Royal Society, November az, 1895. 



271 

refrangible than D3, about the thickness of the line itself, 
which was but narrow '* (Observatory Note-book "). The 
sudden diminution in the brightness of the lines made 
subsequent observations less certain, but the instrumental 
conditions being slightly varied, it was thought that the 
gas line was probably less refrangible than the-Dj line by 
about the same amount that the first observation showed 
it to be more refrangible. Giving the observations equal 
weight, the ^au line would thus appear to be probably 
coincident with the middle of the chromospheric line, but 
if extra weight be given to the first observation, made 
under much more favourable conditions, the gas line 
would be slightly more refrangible than the middle of the 
chromosphere line. 

Pressure of other work did not permit the continuation 
of the comparisons. In the meantime, Runge and 
Paschen announced {Nature, vol. Hi., p. za8) that they 
also had seen the yellow line of the cl^veite gas to be a 
close double, neither component having exadly the same 
wave-length as Dj, according to Rowland. 

They give the wave-length of the brightest component 
as 58^8*883, and the distance apart of the lines as 0*323. 

This independent confirmation of the duplicity of the 
gas line led me to carefully re-observe the D* line in the 
chromosphere for evidences of doubling. On Jane 14, 
observations were made by Mr. Shackleton and myself 
of the D3 line in the 3rd and 4th order spe^a under 
favourable conditions ; ** the line was seen best in the 
4th order, on an extension of the chromosphere or promin- 
ence on the north-east limb of the sun. The D3 line was 
seen very well, having every appearance of being double, 
with a faint component on the red side, dimming away 
gradually ; the line of demarcation between the compo- 
nents was not well marked, but it was seen better in the 
prominence than anywhere else on the limb." (** Obser- 
vatory Note-book "). 

It became clear, then, that the middle of the chromo- 
sphere line, as ordinarily seen, and as taken in the com- 
parison of May 4, does not represent the place of the 
brightest component of the double line, so that exad coin- 
cidence was not to be expeded. 

Though the observations are not yet quite completed, 
the circumstance that the line is double in both gas and 
chromosphere spedrum, in each the less refrangible com- 
ponent being the fainter, taken in conjundion with the 
dired comparisons which have been made, render it 
highly probable that one of the gases obtained from 
cl^veite is identical with that which produces the Dj line 
in the spednim of the chromosphere. 

Other observers have since succeeded in resolving the 
chromospheric line. On June 20, Professor Hale found 
the line to be clearly double in the spedrum of a pro- 
minence, the less refrangible component being the fainter, 
and the distance apart of the lines being measured as . 
o'357 tenth-metres {AsL Nach., 3302). 

The doubling was noted with much less distindhess in 
the spedrum of the chromosphere itself on June 24. Pro- 
fessor Hale points out that Rowland's value of the wave- 
lensth (as well as that of 5875*924, determined by him- 
selion June 19 and 20) does not take account of the fad 
that the line is a close double. 

Dr. Huggins, after some failures, observed the D^ line 
to be double on Tuly xo {Ast, Nach,, 3302) ; he also notes 
that the less refrangible component was the fainter, and 
that the distance apart of the lines was about the same as 
that of the lines in the gas from cl^veite, according to 
Runge and Paschen. 

It may be added, that in addition to appearing in the 
chromosphere, the D« line has been observed as a bright 
line in nebulss by Dr. Copeland, Professor Keeler, and 
others ; in fi Lyre and other bright line stars ; and as a 
dark line in such stars as Bellatrix, by Mr. Fowler, 
Professor Campbell, and Professor Keeler. In all these 
cases it is associated with other lines, which, as I shall 
show presently, are associated with it in the spedra of 
the new gases. 



272 




New Gases obtained from Uraninite. 




1 Cbmical Nbwi, 
1 Dec6»i89S. 


^ave-Iength 


Wave-length 


Chromosphere 


Eclipses 1893. 


Ohon nebula. 


Bellatrix. 


Crookes'a 


(Rowland). 


(Angstrdm), 


(Young). 


Max. intens.-iio. 


Max. intenB.=s6. Max. intens.3>6. 


measures. 






Frequency. 


\R. 


XR. 


XR. 


XR. 


7065-5 


7064-0 


100 


• • 


.. 


• • 


7065-5 


6678-3 


66769 


25 


• • 


.. 


• • 


6678-1 


6371-6 


6370"5 


5 










6347"3 


63462 


10 










6141-9 


6140*6 


15 










6122-43 


6121-43 


5 










60657 


6064-5 


5 










5991 -6 


59900 


15 










5875'9 


5^74-9 


100 


5876-0 


5876-0 


5876-0 


5876-0 


5449-9 


54288 


8 










5404'i 


5403-1 


5 










5048-2 


5047*8 


2 


• • 


• • 


• • 


5047-1 


5015-8 


5015-0 


30 


5016-0(41 
4922-0(4 


.. 


50x6*0(1) 


50x5-9 


4922-3 


4921-3 


30 


4924(3) 


4922-0(2) 


4922^6 


47i3'4 


4712-5 


2 


4713-2(5) 


4716(2) 


4715-0(3) 


4713-4 


4471-8 


^^Zo** 


100 


4471-8(10) 


4472(4) 


4472-0(6) 


4471-5 


43895 


4388-5 


I 


43900(1) 


4390(21 


43890(5) 


43863 


40265 


4025-9 


• 


4026*0^6) 


4026(3) 


4026-0(6) 


4026 'X 


3964-0 


3963*5 


— 


3963-8 , 


.. 


39640(3) 


39648 


3888-7 


3888-0 


— 


probablet 


• • 


probable 


38885 


* Professor Young has recently called attention to the faA that although this line was not included in his chromoanheric list, he 


observed and published it in 1883 ; 


its frequency is about 15. (Natun, vol. 


Hi.. P. 4S8). 






f Tbu line is 


too close to a hydrogen line to enable 


a definite lUtement to be made. 







The Blut Lim, A 4471*8.— A provisional determination 
OQ April 2 of the wave-length of a bright blue line, seen 
in the spedrum of the gases obtained from a specimen of 
cleveite, showed that it approximated very closely to a 
chromospheric line, the frequency of which is stated as 
100 by Young. 

This line was also seen very brilliantly in the tube 
supplied to me by Professor Ramsay on May x, and on 
May 6 it was compared diredly with the chromosphere 
line by Mr. Fowler. The second order grating spcArum 
was employed. The observations in this region were not 
so easy as in the case of D3. but with the dispersion em- 
ployed, the gas line was found to be coincident with the 
chromospheric one. In this case also, the chromosphere 
was observed at the sun's poles, in order to eliminate the 
effeas due to the sun's rotation. 

In a former note (Roy, Soc, Proc, vol. Iviii., p. 114), I 
have pointed out that this line does not appear in the 
spedra of the gases obtained from all minerals which 
give the yellow line. 

Besides appearing in the spedrum of the chromosphere, 
the line in question is one of the first importance in the 
spedra of nebulae, bright line stars, and of the white stars 
such as Bellatrix and Rigel. 

Thi Infra-red Line, Xjods'S'— In addition to D3, and 
the line at 4471 '8, there is a chromospheric line in the 
infra-red which also has a frequency of 100, according to 
Young. On May 28, 1 communicated a note to the Royal 
Society stating that this line had been observed in the 
spedrum of the gases obtained from broggerite and 
euxenite {Roy, Soc, Proc, vol. Iviii.), solar comparisons 
having convinced me that the wave-length of the 
gas line corresponded with that given by Young ; and I 
added ** it follows, therefore, that besides the hydrogen 
lines, all three chromospheric lines in Young's list which 
have a frequency of xoo have now been recorded in the 
spedra of the new gas or gases obtained from minerals 
by the distillation method." 

M. Deslandres, of the Paris Observatory, has also ob- 
served the line at 7065 in the gas obtained from cleveite 
{Comptes Rendus, June X7, x895» P- ^3S^)' 

Other Lines. — Determinations of the wave-lengths of 
many other lines in the spedra of the new gases have 
been made, chiefly with the aid of a Steinheil spedro- 
scope having four prisms, and the results leave little 
doubt as to the coincidence of several lines with those 
appearing in the chromosphere, nebulas, and white stars. 



It seems very probable, also, that many lines which 
have been noted, and for which no origins have yet beeo 
traced, belong to gases which have not hitherto been re- 
corded in the chromosphere. 

The accompanying table summarises the chief lines which 
have so far been recorded in the new gases from varioiu 
minerals, some of which show D3 while others do not. 
Only those lines which also appear in the spedrum of 
the chromosphere, nebulas, or Orion stars, are given in 
the first instance. There are other lines which are pro- 
bably also associated with chromospheric ones, but further 
investigation of them is considered desirable before they 
are included in the list. 

The first column of the table gives the wave-lengths of 
the lines on Rowland's scale, wbiie the second gives the 
wave-lengths on Angstrom's scale ; the third gives the 
frequency of the lines in the chromosphere according to 
Young. In the fourth column lines photographed with 
the prismatic camera during the total eclipse ot April x6, 
1893, ^fc shown ; these have been included because in 
some cases lines which appear to be comparatively unim- 
portant in Young's list were photographed as important 
lines. The fifth column indicates probable coincidences 
with lines in the spedrum of the Orion nebula ; the acca- 
racy of these wave«lengths is of necessity less than in the 
case of the chromosphere ; with the exception of Dj they 
are taken from my paper on the photographic spedrom 
of the Orion nebula {Phil, Trans,, X895, vol. clxxxvi. A, p. 
76). The 8 xth column shows probable coincidences with 
dark lines in the spedrum of Bellatrix, this being taken 
as an example of the Orion stars {Phil, Trans,, Z893, vol. 
clxxxiv. A, p. 695)1 ^bc lines 4922*3 and 50x5-8 have been 
photographed since the date of the paper to which refer- 
ence is made. 

The last column gives the wave lengths, from Mr. 
Crookes's table, of the lines observed by both of us. 



Royal Institution. — A General Monthly Meeting of 
the Members of the Royal Institution was held 00 
December 2nd, Sir James Crich ton-Browne presiding. 
The following were eleded Members : — Messrs. C. H. 
Berners, T.P., J. M. Bruce, M.D., F. Chambers, A. M. 
Chance, J.P., A. E. Fletcher, F. Fox, J.P , H. Sevmonr, 
K. T. Stewart, M.D., G. H. Strutt, F. Tendron, F.O.S., 
W. H. Warner, M. Webb, J.P., and Mrs. S. H. Phillips. 



CliBinc4i. Htvt, I 
Dm. 6* 1695- I 



Experimental Proof of van U Hoff^s Constant^ &c. 



273 



EXPERIMENTAL PROOF OF VAN 'T HOFF'S 

CONSTANT, OF ARRHENIUS»S GENERALISA- 

TION, OF OSTWALD'S LAW OF DILUTION. 

OF DALTON»S LAW, &c., 

IN VERY DILUTE SOLUTIONS* 

By Dr. MEYER WILDERMANN. 

Thb followiDg forms the foandation of the new theory of 
eolations : — 

1,— Proof of van H Hoff'% Constant 
It was van *t HofiF who first drew attention to the fad 
that the equations representing the generalisations 
arrived at by Boyle, Gay-Lussac, and Avogadro in the 
case of gases are equally applicable to dissolved sub* 
stances, if the osmotic pressure of the molecules of the 
dissolved substance be substituted for the pressure of the 
gas. Van 't Hoff deduced these laws for solutions from 
thermodynamical considerations {Ztit, Phys, Chim,, i., 
1887) — a method which gives them increased validity — 
and illustrated them from the osmotic experiments of 
Pfeffer and de Vries. Soon after, Prof. Max Planck de- 
duced van *t Hoff *s laws in a very elegant way, also from 
thermodynamical considerations {Wied. Ann., xxxii., 
1887). Lorentz (Z#tf. Phys, Chtm,, vii.), Boltzmann 
{Ztit. Phys. Chtm,, vi., vii.), Riecke (Ztit, Phys, Chtm,, 
vi.), and Van der Vaals {Ztit, Phys, Chtm,, v.) have de- 
duced the gaseous laws from the kinetic theory. 

At the tame time van 't Hoff was able to establish a 
thermodynamical relation between the osmotic pressure 
of a dissolved substance and the molecular lowering of 
frcesing-point of the solution, thereby furnishing a rational 
basis for the empirical generalisations of Raoul, Babo, 
and WuUner, who had previously investigated the same 
point (Ztit. Phys, Chtm,, i.) ; later on Planck deduced 
the same thermodynamical relations IWitd, Ann,, xxxii., 
1887). 

In van 't Hoff's thermodynamical argument the solu- 
tions are assumed to be very dilute, and hence their ex- 
perimental verification is of special importance in very 
dilute solutions. The determination of the molecular 
freesing-point is the safest and the most convenient 
method of testing the validity of these generalisations ex- 
pcrimentallv, and this has been done for moderately 
dilute solutions by van 't HofiF himself, and by Eykmann, 
and the equation — 

0*02 7* . 

w 

where T ■> absolute temperature, w » latent heat of 
fusion of the solvent, has been experimentally verified 
and confirmed for several solvents. The method of deter* 
mining the freezing-point in venf dilute solutions of my 
late friend P. B. Lewis (Trans. Chtm. Soc, 1894 ; a fuller 
account has been given in Ztit, Phys, Chtm,, xv., p. 358), 
m^ investigations on the same matter (** On the Deter- 
mination ot the Freezing-point of Water," Zeit. Phys. 
Ch4m,, zv., p. 365. See ** On the Real and Apparent 
Freezing-CKDints and the Freezing-point Methods,*' then 
** On the Determination of Freezing-point in Dilute Solu- 
tions to 0*4^ Depression,'* which I shall publish shortly in 
Phil, Mag. and in Ztit, Phys. Chtm,) give us the possibility 
of sobmitting van 't HofiT's equation, — 



I « 



o'oa T« 



to a more accurate verification. I give a full account of 
the freezing-point method, since it is important to know 
not only what one gets, but how it is got. This is 
especially necessary in view of the different contradidory 
resulu which have been published and are due to insuffi- 



* Rsad bcforv the British Association (ScAion B), Ipswich 
If Mtiof , 1893. 



cient, and often more than insufificient, development of 
the method used. Last year I investigated a series of 
bodies (Phil. Mag., July, 1895) ; this year I investigated 
cane-sugar, urea, alcohol, dextroset resorcin, maltose, 
milk-sugar, glycerin, with the convergence temperature 
above and below the freezing temperature, with the 
YoVo^and thex^o*' thermometer, with different parts of 
the scale. The obtained results are in excellent agree- 
ment with van *t Hoff *s theory. 

2. — Arrhtnius*s Otntralisation. 
Van 't Hoff showed, by four different methods, that a 
generalisation analogous to that of Avogadro was valid 
for solutions of non-elearolytes, like cane-sugar ; it then 
became of importance to account lor exceptional cases, in 
which the depression of the freezing point was abnormal, 
and in particular the cases of salts, acids, and bases in 
aqueous solutions. The explanation was given when 
Arrhenius showed that, by two independent, quite dif- 
ferent, methods, the observation of the lowering of 
freezing-point and of the eleArical condu^ivity of a solu- 
tion, the same value would be obtained for the fador i, 
which denotes the ratio of the pressure adually exerted 
by the substance to the pressure which the substance 
would exert if it consisted entirely of undissociated 
molecules. Arrhenius made determinations on about 
forty bodies in moderately dilute solutions of various 
concentrations, and verified his generaliiation. From 
the intimate connedion which exists between van *t 
Hoff*s laws and the dissociation theory, it follows also 
that the generalisation of Arrhenius may find a more 
exad experimental confirmation in dilute solutions. 
This is not only important on account of the great light 
which the theory of dissociation has thrown upon the two 
provinces of chemistry and physics, but it is also impor- 
tant inasmuch as thereby the laws of van *t Hoff will 
find in every point their more exad confirmation (see 
also Max Planck, Witd, Ann., xxxiv.). 

Last year I investigated sulphuric acid, potassium 
chloride, dichloracetic acid, orthonitrobenzoic acid, 
trichloracetic acid, with the convergence temperature 
above the freezing temperature (Phil. Mag,, July, 1895); 
this year, with the convergence temperature t>elow the 
freezing temperature. Besides these bodies I investi- 
gated nitric acid, hydrochloric acid, potassium chloride, 
sodium chloride, ammonium chloridOt &c., with the con- 
vergence temperature below the /reezing temperature. 
Arrhenius*s generalisation finds the most wonderful con- 
firmation. 

3. — The Law of Dilution. 
This forms one of the most important foundations of 
the theory of dissociation. It was Ostwald who first showed 
the relation between the dissociated and undissociated 
molecules to depend upon the aAion of masses, and took 
pains to verify the same in the case of about two hundred 
acids by means of their eleAric conduAivity (see, also, 
Max Planck, Witd. Ann., xxxiv.). 

From the above-mentioned generalisation of Arrhenius 
it follows that the law of dilution ought also to be 
deducible from the freezing-points, since the freezing- 
points, as well as the ele^ric condudivity, enable us to 
know the degree of dissociation, and it may be interest- 
ing inasmuch as we have not here to do with velocity of 
ions or with the theory of eledric condudivity. 

From the intimate connexion which exists between 
van *t Hoff*s laws and the theory of dissociation, it fol- 
lows that the law of dilution must find its experimental 
confirmation in dilute solutions ; the freezing-point 
methods have not been till now sufficiently exad for this 
purpose ; now we are able to undertake it under favour- 
able conditions. 

I investigated orthonitrobenzofc acid, dichloracetic 
acid, trichloracetic acid, with the convergence tempera- 
ture above {Phil. Mag. July, 1895) and below the freezmg 
temperature, and found that the law of dilution finds a 
good confirmation also by this second way. 



274 



Chemical Researches and Spectroscopic Studies. 



CBBNICAi. KbWS, 

Dec. 6, 189s. 



4. — DaltofCs Law in Solutions, 
Dalton'8 law, at we know, declare! that the total prei- 
■nre of a mixture is equal to the sum of the partial pres- 
sures exerted bv the constituents of the mixture in the 
given space. This law, for the same reason as the law of 
Boyle and Gay*Lus8ac, holds good only in the case of 
dilute gases. Since van 't HofiF has shown that the law of 
Boyle and Gay-Lussac is to be applied for dilute solu- 
tions (see van't Hoff's constant), the conclusion may 
logically be drawn that the third gaseous law— the law 
of Dalton — exists in solutions also. For some reasons, 
which cannot be further discussed here, the best mode of 
testing Dalton's law in solutions is the freezing-point 
method. I investigated, for this purpose, mixtures of 
urea and resorcin, of urea and cane-sugar, of urea and 
dextrose, of dextrose and cane sugar ; the obtained results, 
in very dilute solutions (with the convergence tempera- 
ture under the freezing. point), are very satisfadory— no 
less than in the case of the proof of van't Hoff's 
constant. 

5. — On ik$ Degr$e of Dissociation in Solutions whin 
Non^tUctrolyies an present. 

It has been found that the degree of dissociation of a 
gas does not change in the presence of an indifferent gas. 
This is also to be regarded as a consequence of Dalton*s 
Law for the partial pressures of the constituents of a 
mixture. I find the relations to be quite analogous in 
the case of eledrolytic dissociation. I investigated the 
influence of glycerin upon dichloracetic acid, upon ortho- 
Ditrobenzoic acid, &c. ; the result is, that no change (at 
any rate no considerable change) in the degree of di8so> 
ciation takes place, even in the case of dichloracetic acid 
and orthooitrobenzoic acid. These investigations of the 
influence of non>eleAroIytes on the degree of dissociation 
if the method of freezing-points is of special interest, 
since, besides the phenomena under consideration, the 
theory of eledric condudivity can be more easily sur- 
veyed and understood by this than bv using the method 
of eleAric condudivity (as has been done by Arrhenius) 
where the above phenomenon is complicated by the 
change of the velocity of ions, owing to the change of 
the inherent viscosity (*' innere Reibung '*) of the liquid. 
Using the method of freezing-points, we are able to 
isolate the phenomena and to come to a clear conception 
of both of them. At any rate no considerable redu^ion 
of the degree of dissociation, I find, takes place when 
non-eledrolytes are present, and the diminution of the 
eledric conduAivity of a dissolved eledrolyte in the pre- 
sence of a non-eledrolyte must, more or less, be entirely 
attributed to the change of the inherent viscosity. 

6.— Ofi the Reduction of the Degree of Dissociation 

by introducing a Common Ion. 
I have already drawn attention to the importance of the 
law of dilution as a proof of the theory of dissociation, 
which shows that the relation between the dissociated and 
vndissociated molecules depends upon the well-investi- 
gated and established law of adion of masses. A second 
proof of the theory of dissociation, based upon the same 
law of adion of masses, is the redudion of the degree of 
dissociation by the introdudion of a common ion. In 
the case of a dissociated gas, a redudion of the degree of 
dissociation takes place if one of the dissociated parts is 
introduced. It was Arrhenius who first, in his paper, 
«' Theory of Isobydric Solutions " (Zeits, Phys, Chem., ii.), 
drew attention to this important point, as a proof of the 
theory of dissociation. Arrhenms himself proved this 

Suestion but little, usin^ the method of eledric con- 
udivity. A more searchmg investigation of this matter 
by the method of eledric condudivity has been under- 
taken at the same time by Prof. Ostwald in Leipzig, and 
myself in Oxford. It is important to mention that the 
agreement between the theory and the obtained results is 
very satisfadory . Here I give the results which I obtained 



by the investigation of the same matter in dilute solu- 
tions by a second method — the freezing-point method* 
I investigated the redudion of dissociation in the case of 
mixtures of hydrogen chloride and orthonitrobenzoic 
acid, hydrogen chloride and dichloracetic acid, nitric acid 
and orthonitrobenzoic acid, nitric acid and dichloracetic 
acid, nitric and hydrochloric acid. &c. I have calculated, 
owing to want of time, only a part of my experimenul 
results, and, as £sr as my calculations have been carried 
out, the agreement between the theory and the experi- 
ments is quite satisfadory. I draw attention to the fad 
that, while non-eledrolytes did not produce redudion of 
dissociation in the case of dichloracetic acid and ortho- 
nitrobenzoic acid, we, quite in accordance with the law 
of adion of masses, have been able for the same bodies, 
by introducing common ions, to observe redudions of dis- 
sociation which amount even to 60 or 70 per cent of the 
total value of the degree of dissociation. 
Chriit Church, Oxford. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 
STUDIES OF VARIOUS ELEMENTS. 
By J£AN SERVAIS STAS. 
(Oontiooed from p. 261). 

B. Air of the Laboratory, — The laboratory, situated on 
the second floor, consisted of two rooms, one of which 
looked on to the street and the other on to the garden. 
These rooms communicated with each other by a door, 
and had in addition a door opening on to the landing, 
which supplied them with air coming from the roof or 
basement, according as the door of the loft or basement 
was open or shut. 

The apparatus for condensing vapour from the air was 
freely suspended in the back room, in a very large glass 
cage, havmg in its upper part a large opening which could 
be lessened at will, conneded with a ventilating shaft, 
and receiving air from the room through a large opening 
70 cm. above the floor. 

The spedroscope was placed in the same room, 1*5 
metres from the condensing apparatus. The front room, 
the landing'door of which was open, supplied air to the 
back room. 

I St. The wind was blowing from the east, the air 
came from the yard in the south-west, by the staircase 
well and the landing. The temperature of the air in the 
glass cage was 22*5°; dew- point was 15*2*'. The weight 
of water condensed was 132 grms. During the penod 
of condensation of water vapour, the temperature of the 
disulpbide of carbon was between o^ and 3**. The flame 
of a gas-lamp burning close to the apparatus was blue 
slightly tinged with violet, and spedrum analysis of this 
flame showed a persistent weak sodium line masking any 
other spedrum. 

I only succeeded in realising these conditions by the 
care I took in dusting both rooms, and everything in them, 
two days previously, in having the floors carefully washed 
as well as the stairs, and in abstaining from working in 
the laboratory. When I did not take these precautions I 
always saw bright points in the flame. 

Five drops of a 10 per cent solution of nitrate of silver 
caused a slight precipitate in 10 c.c. of filtered water. 
One drop of a saturated solution of chloride of barium, 
added to 15 c.c. of filtered water, gave no precipitate ; 
but the mixture, when evaporated down to about half a 
c.c, became perceptibly clouded. 

One hundred cc of filtered water left, on evaporation, 
a rich yellow stain weighing 0*000065 grm. The stain 
turned black when heated ; the residue was dissolved by 
two drops of water, and the solution when put into the 
flame coloured it yellow, intensely but temporarily. 
Spedrum analysis showed the sodium line and a very 
faint calcium spedram. 



CVBMtCAL NbW% I 

D«c. «, 1895. f 



Chemical Researches and Specotrscopic Studies. 



275 



The ioner filter, throagh which the water pasied, when 
dried, WM the same colour at paper exposed to the atmo- 
•pberic doBt of the laboratory. Under the microscope I 
taw a number of black and sparkline grey specks, as well 
at filaments. After burning the carbon made by carbon- 
iting the inner filter in a closed vessel, there remained a 
brown ash weighing 0*000105 grm. Daring combustion, 
the part of the flame afieded was coloured deep yellow. 
The atb, when moistened with chloride of ammonium 
and pot into the flame, showed sodium and calcium 
tpedra, bat not a trace of a potassium speAnim. The 
fisidae, when treated thrice with fluoride of ammonium 
to eliminate the silica, and put into the flame, still 
showed the sodium line without the potassium line. 
Lastly, the brown marks left on the fine platinum wire 
loop, when treated with pure sulphuric acid and put once 
more into the outer envelope of the flame, showed the 
todium line still, with a veiy faint calcium spedmm, but 
no trace of the potassium line. 

2nd. Air from tht stnet, running east and west, en- 
tering by an opening on the south, by way of the roof 
and loft : — 

The air brought into the laboratory by the draught of 
Ibar ventilating shafts with which it was famished, 
coloared a Bunsen flame distindly violet ; on speArum 
anal3rsit, a faint but decidedly yellow sodium line was seen, 
without m trace of the calcium spedrum ; outside, the air 
temperature was 27*3^ ; in the glass case it was 23*8*, and 
dew-point was 17*7* ; there were coUeded 135 grms. of 
filtered water, neatral to litmus-paper. 

Five drops of a 10 per cent solntion of nitrate of silver 
made m tcntible precipitate in 10 c.c. of filtered water. 

Twenty c.c. of filtered water were evaporated down to 
about half a c.c. This liquid was sensibly clouded by 
adding one drop of a saturated solution of chloride of 
barium. 

One hundred c.c. of filtered water, when evaporated to 
drynett, left a sparkling brown stain, weighing 0000057 
grm. This residue blackened when heated; when dis- 
solved in two drops of water, and put into a flame, the 
solution coloured it yellow. SpeArum analysis showed 
the sodium line, as well as a faint calcium spedrum. 

The inner filter, through which the water passed, when 
dried, waa the same colour as paper exposed to the dust 
of the laboratory; under the microscope it showed 
sparkling and transparent black and grey specks, stains 
iust like day, moistened and dried, aa well as organic 
filaments, some long, others short. 

After burning the carbon made by carbonising the filter 
in a closed vessel, there remained a brown siliceous aih, 
weighing 0*000147 grm. During combustion, spedrum 
analysis showed a strong sodium line. This ash, when 
moistened with chloride of ammonium, coloured the 
flame intense yellow, showed a sodiam spcArum and a 
faint calcium spedmm all the time, but no traces of a 
potaasium spedrum. 

Having eliminated the free and combined silicic add by 
means off fluoride of ammonium, then treating the reai- 
doewith solphnric acid, I deteded in the produd faint 
indications of the presence of sodium, calcium, alumi- 
nium, and iron ; but I utterly failed to find any trace of 
potassium. 

If we admit that the methods I adopted for ascertaining 
the nature and amount of sodium and calcium compounds 
in the air give correa results, we must conclude from 
them that air, when deprived by rain of the dust it had 
in sntpention, and kept saturated or nearly so by rain, 
does not contain in from zo to 15 cubic metres an amount 
of toluble sodiam compounds capable of being weighed 
fai a balance weighing to thru thousandths of a m grm. 
There is sodium in it nevertheless, although speArum 
analysis of a Bunsen flame burning in it does not show 
the sodium line. 

In this manner the presence of sodium is accounted for 
in hygrotoopic bodies, other than todiam compounds, ex- 
posed to the air and sheltered from dust partides ; for 



they— by liquefying it by absorption of, and depositing It 
by condensation of; the water in the air— persistently give 
indications of the presence of the metal sodium. Such 
are undoubtedly the chlorides of calcium and lithium, at 
I show in chapters devoted to the chemical and spearo- 
scopic studies of these bodies. Neither outside nor inside 
air, whin still, contains a measurable amount of soluble 
sodium compounds in from xo to 15 cubic metres, although 
they give the sodic charaderistics to flames. The quantity 
of insoluble sodium and calcium mineral matters in this 
amount of air varies from six to fifttin hundrtdths of a 
m.grm* 

I have noted the presence of potassium amongst the 
mineral matters in free air in certain distrids. 

In spite of all efforts I cannot deted a trace of either 
soluble or insoluble potassium compounds in thi airoj iht 
higher part of Brussels. 

Rain Water,— I thought it useful to check my re- 
searches in air by making a comparative examination of ft 
the water condensed from saturated air, and rain water 
colleded when there was no wind, 1 worked with rain 
which fell by day as well as by night, in order to better 
understand the part played by chimneys in contaminating 
the air. 

The rain water was colleded in the middle of the 
garden, i metre above the ground, after the air had been 
washed by several days' drizzle. Under these conditions 
it teemed that the rain water ought only to contain 
tracet of the mineral matters in the clouds suppljriog the 
rain, to which would be added the compounds emanating 
from chimneys. 

To colled the rain water, I put on a board, i metre 
above the lawn, five Bayeux porcelain dishes, 40 cm. 
diameter. In addition I arranged, at a side of the yard 
leading to the garden, a cloth to shelter the spedro- 
scope, Bunsen lamps, and everything I wanted to filter 
and evaporate the colleded rain water. All experiments 
on rain water wtre conducted in the open air, which was 
saturated with moisture but not misty. As it was col- 
leded the water was poured into a covered platinum 
vessel, and filtered after weighing. I used for this pur- 
pose double filter-papers, which were first treated with 
dilute and pure nitric and hydrofluoric acids, and finally 
with water. The double filter- papers were arranged In a 
platinum funnd passing through a hole in a sheet of po- 
lished glass on a platinum retort, in which was colleded 
the weighed and filtered water. 

To ascertain the nature and quantity of matters either 
dissolved or left in the filter, I did as I have described 
above with water condensed from the vapour in the air. 

Whilst I was coUeding the rain water I worked the 
condensing apparatus outside the window on the second 
floor and sheltered from the rain, so as to be able to com- 
pare both results. 

Rain Water fallen during the Day. — Wind, none; 
temperature of the air, 8*13^; rain water colleded be- 
tween 8 a.m. and 3 p.m., 153 grma. 

All day long the Bunsen lamp burnt in the yard, umd^r 
the canvas, which was quite soaked with the rain, withont 
showing a trace of the todium line on spedrum anal3rsit. 
It was the same outside the second floor window under 
cover, where the apparatiu for condensing the atmospheric 
moisture was working. Dew-point was 7*90*. The water 
colleded weighed 138 grms. # 

The filtered rain water was colourless, and neutral to 
litmus-paper. When sprayed into a Bunsen flame, bum* 
in the court under the wet canvas, by means of a metallic 
injedor with steam from pure water, it turned the flame 
disrindly yellow, Spedram analysis of the jrdlow flame 
showed the sodium line, hitherto invisible in the flame 
burning in air, or in the flame with pure water coming 
from the apray, which had been purified from sodiam 
dust. 

Five drops of a xo per cent solution of nitrate of silver 
made a very decided precipitate in 20 c.c. of filtered rmn 
water. Five drops of a 10 per cent solution of nitrate of 



276 



Chemical Researches and Spectroscopic Studies. 



i Chkmical Ncwty 
I Dec. 6, 1895. 



■liver made a very slight cloadinesB in 20 c.c. of filtered 
waUr of condensation. One drop of a saturated solution 
of chloride of barium gave no precipitate in 10 c.c. of 
filtered rain water. After evaporating 20 c.c. of rain 
water down to about half a c.c, the residue was very 
slightly clouded by one drop of a saturated solution of 
chloride of barium ; whereas after evaporating 18 c.c. of 
watiT of coniUnsation down to about half a c.c, the 
residue was not affeAed in the slightest degree by one 
drop of a saturated solution of chloride of barium. 

Filtered rain water, when being evaporated on a bath, 
emitted a smell of fog similar to that noticed after rain. 
One hundred cc of this water, when evaporated down 
to about z cc, yielded a cloudy brownish yellow liquid. 
This liquid, when evaporated to dryness on the bath, left 
a brown hygroscopic residue weighin|r 0*000x91 grm., 
whilst zoo cc. of water of condensation left a brown 
stain weighing only 0*000027 grm. The residue left, 
after evaporating the rain water to dryness, turned very 
black, and emitted a smell like coal-tar, when raised to 
a dull red heat in a closed vessel. This residue, when 
dissolved by a few drops of water and put into a Bunsen 
flame, coloured it yellow, and showed on spedrum 
analysis a brilliant but temporarv sodium spedrum, as 
well as a weak and incomplete calcium spedrum, but no 
trace of the potassium line. 

The filter through which the rain water had passed, 
when dried, showed a dark grey tint all over its surface, 
a vast number of black specks, and also filaments. 
When carbonised in a closed vessel, and then burnt, it 
left a reddish brown siliceous ash, weighing 0*000225 
grm. per 100 cc. of filtered water. 

During combustion I saw the sodium line, but no trace 
of a calcium or potassium spedrum. When moistened 
with chloride of ammonium, the ash showed an ill- 
defined sodium and a very weak calcium spedrum. After 
eliminating the free and combined silicic acid by means 
of fluoride of ammonium, and then treating it with sul- 
phuric acid, I still saw a sodium and a very weak calcium 
spedrum, but no potassium line. 

The inner filter, through which the water of condensa- 
tion from atmospheric vapour had passed, when dried, 
carbonised, and burnt, left 0*000042 ^rm. of brown sili- 
ceous ash, containing sodium and slight traces of cal- 
cium ; but I could not deted the presence of potassium 
in it by spedrum analysis. 

Rain Water fallen during the Night, — There had been 
a fine rain all night, but no wind. The results of the 
experiments were of the same nature as those above. 
For instance, it was necessary to concentrate the filtered 
water to jio^^ of its volume in order to deted, with ni- 
trate of silver, the presence of chlorine, and to ,'oth of 
its volume to prove the presence of sulphuric acid by 
means of chloride of barium. 

The residue, after evaporating 100 c.c. of filtered 
water, was brown and weighed 0*000x15 grm., and con- 
sisted chiefly of tarry matters, with traces of volatile 
compounds of sodium and calcium, but not of potassium. 

The filter through which the nodumal rainfall had 
passed was considerably less stained than that used to 
filter rain fallen during the day, and the weight of the 
brown ash left on burning it was only 0*000098 grm. 
per 100 c.c. of filtered water, — that is to say, less than 
half the weight of the ash of the filter through which an 
equal volume of rain water colleded by day nad passed, 
wnich was 0*000225 grm. 

This last fad tends to show that, when there is no wind, 
the chimneys contribute largely to the contamination of 
the air by the mineral matters which are found in it near 
crowded neighbourhoods, and that the remainder may per- 
haps be attributed to rain clouds. But before coming to a 
general conclusion these experiments ought to be tried a 
great number of times, and this can hardly be done 
excepting in a building fitted up for meteorological re- 
search. 

I ascertained, besides, by many trials, that the rain 



entrapped the soluble and insoluble matters suspended in 
the air so thoroughly, that, after very heavy rain, the last 
showers gave water so free from chlorides and sulphates 
that I had to evaporate it down to ^Joth of its original 
volume before I could deted chlorine and sulphuric acid 
in it by nitrate of silver and chloride of barium. During 
the summer of x88x I not only found that chlorine and 
sulphuric acid were not present in the rain which fell at 
the end of a very heaw storm, but after the rain ceased 
I found the outer air left for several hours during the day 
in such a state of purity that it was absolutely impossible 
to deted a trace of the sodium line in the spedrum of m 
Bunsen flame burning in it. 

With very rare exceptions coal and coke are used in 
Brussels as fuel ; I attribute to this the absence of 
potassium, for it has been deteded in the atmospheric 
dust of other distrids. 

I think it is scarcely necessary to mention that the 
results given above are only applicable to the atmospheric 
conditions existing at the time of my experiments. In 
truth, long experience has taueht me the great variation 
in the nature of atmospheric dust, according to the pre- 
vailing winds. I cannot say that I have on a single occa- 
sion found the air of the higher part of the town the 
same twice running as regards dust. The air appears 
most free from mineral dust after a fine rain without 
wind, and whilst it continues raining. In this case the 
suspended dust particles are always blackened by coal- 
smoke. 

I have ascertained beyond a doubt, by observations 
extending over more than a third of a century, that the 
dust brought by the air, with or without rain, shows a 
density of colour, always varying according to the direc- 
tion of the wind which brings it. 

The air which passes over the town from the north or 
north-west, towards the south or south-west before reach- 
ing the street in which I live, always brings with it a fine 
siliceous dust more deeply blackened by coal-smoke than 
that entrapped by the fine rain which falls when there is 
no wind. The air brought by a south or south-east wind, 
with or without rain, brings a greasy, more or less 
yellow, dust. 

Lastly, the air brought by an east wind, with or without 
rain, brings a grey dust, with a sandy, clayey charader. 

According as buildings are raised in my neighbourhood, 
which was originally quite open, on the east, south, or 
south-west, so have the physical properties of dust depo- 
sits remarkably changed, without, however, attaining each 
other's specific charaderistics. 

The fads I have mentioned here ought to be met with 
in all distrids. Whenever accurate observations are 
made everywhere, no doubt we shall find that they are due 
to the dust of the air as well as to the water which flows 
along the ground, abstrading from it the soluble bodies 
it contains, no matter what may be the nature or origin 
of these bodies. 

The nature of the dust particles ought to have some 
connedion with the composition of the soil swept by the 
wind, and the smoke poured into the air by fadories and 
chimneys. 

(To be continued). 



King's College.^Free Ledure.^On Monday next, 
the 9th inst., a Free Leduie will be given to the Public, 
in the Theatre of the College, by Prof. Thomson, F.C.S., 
&c., on ** Movements of Gases and Liquids " (Experi- 
mentally Treated), commencing at 8 p.m. 

On the Neutral Crystalline Calcium Cbromite.—E. 
Dufau. — At a sufiiciently high temperature chromium 
sesquioxide combines diredly with lime, forming a chro- 
mite of the formula Cra03CaO. It is crystalline and 
stable at the highest temperatures. Its specific gravity 
is 4*8 at xS^and it resists the adion of the most powerful 
^Qid:—Comptes Rendus, cxxi., No. 20. 



Chemical NEWt,l 
Dm. 6, 1895. f 



A ctdylthiocarbimides. 



277 



PROCEEDINGS OF SOCIETIES. 

CHEMICAL SOCIETY. 
Ordinary Meeting, Novtmbtr yth, 1895. 

Mr. A. G. Vbrnon Harcourt. President, in the Chair. 

(Ooncluded from p. 266). 

135. '* Normal Hexans from Light Peirolium (PetrO' 
UmmBtk^r).** By G. L. Thomas, B.Sc., and Sydnby 
YouMO, D.Sc., F.R.S. 

Having devised an improved form of depblegmator 
(Chemical Nbws, Ixzi., 177) we determined to attempt 
the separation of a pore paraffin from ** petroleum ether *' 
in the same waj that ethyl acetate was separated from a 
inixtnre of methyl, ethyl, and propyl acetates {Phil, Mag*, 

'^94. 8). ..... 

Each fraAion was weighed, and its temperature range 
noted and correAed for the thermometric error and for 
the difference between the barometric reading and 760 
n.m. The ratio of the weight of any fradion (Anr) to its 
temperature range {At) gives, as a rule, a measure of the 
parity of the liquid, though in the early fradionations of 
a complex mixture this csnnot be relied on. 

Thus, in the 4th fradionation the fradion coming over 
between 65*0* and 66*0* had the highest value of AwjAt, 
whereas in the x6th fradionation the corresponding frac- 
tion (65*0^ to 66*85°) had the lowest value. At an early 
stage of the work it appeared, therefore, as though a 
single substance boiling at about 65^ or 66^ was being se- 
parated from liquids boiling at much higher and lower 
temperatures (above 90^ and below 40*") ; but the later 
fradtonations showed that instead of a sinsle substance 
boiling at about 65° or 66°, there were really two liquids 
— one boiling at 69*, and the other at about 61* (normal 
and iso-hexane). 

As the number of fradions was very large, it was de- 
cided after the z6th fradionation to proceed only with ^he 
separation of normal hexane, and after 31 preliminary 
fradionationa it was considered that the separation had 
proceeded far enough for the final series of fradionations 
to be underuken, as in the case of ethyl acetate {loc, cit.). 
The hexane obtained by the final fradionation of the frac- 
tions boiling at and above 69*05**, when distilled from 
pfaosphoras pentoxide, boiled at 69*1*, or only o'l** higher 
than the hexane prepared from propyl-iodide, but its 
sp.gr. at o* (0*68478) was 1*15 per cent higher. The 
bcxane was then treated with a mixture of concentrated 
snlphuric and nitric acids, when considerable heat was 
evolved, and the acid became yellow, and was found to 
contain some wi-dinitrobenxene in solution. The impu- 
rity present was therefore benzene or possibly hexanaph- 
thene, or both. 

The remaining high-boiling fradions were treated with 
the mixed acids and were refradionated ; the low-boiling 
fradions also were treated in the same manner before 
tbeir final fradionation, and in every case it was found 
that M-dinitrobenxene was formed. 

By farther long-continued treatment of the two speci- 
Bseos of hexane with the mixed acids and subsequent 
distillation, a quantity was finally obtained boiling at 
69'05° and with the sp. gr. 0*67813 at o^ or only 0*17 per 
cent higher than that of pure hexane. 

The vaponr pressures and specific volumes — as liquid 
and as saturated vapour — were determined at a few tem- 
peratures, and the critical temperature and pressure were 
also observed ; the results differed but slightly from those 
obtained with the hexane from propyl iodide. The critical 
constants of both specimens are given below : — 

Critical Critical 
temperatart. preaaare. 

Hexane from petroleum ether . . 235*15 22560 
Hexane from propyl iodide.. .. 234*8 22510 

The hexane waa evidently very nearly pure, but the 



separation of this paraffin from petroleum ether is only 
possible by long-continued fradional distillation with an 
efficient depblegmator, and by removal of benzene or 
hexanaphtbene with nitric and sulphuric acids. 

126. •• The Vapour Pristuns, Specific Volumes, and 
Critical Constants of Normal Hexane,*^ By G. L. 
Thomas, B.Sc., and Sydney Youno, D.Sc., P.R.S. 

The normal hexane employed was obtained from Kahl- 
baum, and prepared bv the adion of sodium on propyl 
iodide. It was purified by treatment with concentrate 
nitric and sulphuric acids and subsequent fradional dis- 
tillation. 

The boiling' point at 760 m.m. is 69*0^ and the sp. gr. 
at 0° is 067696. The critical constants are — 
Critical temperature • • .. 2348^ 
Critical pressure •• •• 225x0 m.m. 
Critical volume of a grm. • • 4*268 c.c 

The vapour pressures and the volumes of a grm. — as 
liquid and as saturated vapour — were determined, and a 
limited number of observations of pressure and volume 
of unsaturated vapour were made at a series of tempera- 
tures with the objed of finding whether the isochors 
showed any indication of curvature. As in the case of 
isopentane (in about the same volume region) the isochors 
were found to be very slightly curved, the values of dpjdi 
diminishing ;vith rise of temperature. The deviations 
from constancy become smaller as the volume increases. 

The absolute temperatures and molecular volumes of 
liquid and saturated vapour were read from the curves at 
a series of pressures ** corresponding '* to those given in 
previous papers, and the ratios of the absolute tempera- 
tures and of the volumes to the critical constants were 
calculated. These ratios agree with those of isopentane 
and benzene ; normal hezane therefore belongs to Group 
I. in the classification of substances previously adopted 
{Trans, Chem. Soc, Ixiii., 1257; ^A'^* ^^^'* i^t Of ^^^ 
the molecules of the liquid are probably simple like those 
of the gas- 

The absolute temperature ratios at corresponding 
pressures are higher for hexane than for isopentane ; in 
this retped the paraffins seem to resemble the esters 
{Trans. Chem, Soc, Ixiii., 1252), for which the ratios in- 
crease without exception with rise of molecular weight. 
In the case of the esters, the volume ratios appear to be 
independent of molecular weight, but—for isomeric com- 
pounds — to depend to some extent on the constitution. 
It seems probable that this may also be the case for the 
two paraffins studied, but an investigation of other 
paraffins will be necessary before these points can be 
decided. 

The ratio oT the adual to the theoretical density at the 
critical point is 3*83, the mean value for the other members 
of Group I., including carbon dioxide (Amagat) and iso« 
pentane, being 375. 

127. ** AcidylthiocarbimidesJ'* By Augustus £. DixoM, 
M.D. 

This paper gives an account of further experiments (see 
Dixon and Doran, Trans. Chem. Soc, 1895, Ixvii., 565) on 
the produdion of thiocarbimides containing acidic radicles. 
By heating the chloride of valerianic or of cinnamic 
acid with lead thiocyanate in presence of anhvdrons ben- 
zene, valeryl or cinnamoyl thiocarbimide is formed, and 
passes into solution. Both these thiocarbimides have a 
slightly pungent odour, and attack the eyes, causing a flow 
of tears, the former being especially adive. They are 
readily desulphurised by lead or silver salts, but decom- 
pose in presence of water, yielding thiocyanic acid, to> 
gether with the acid charaderistic of the thiocarbimide,— 

Ph-CH:CH*CO*NCS -I- HaO - 

- HSCN + PhCH:CH*COOH. 

By bringing the solutions into contad with ammonia, 
amines, or ethyl alcohol, the corresponding thioureas, 
thiocarbimides, or tbiourethanes, respedively, are pro* 
duced. 



278 



Piperovatme. 



ICbbmicalNbws. 

I Dec. 6, 1805. 



The following compounds are described : — 
ab-VaUrylphtnyUhtocarbamidt, BuCONH-CSNHPh ; 
•ym. vaUiylphtnylurta, BuCO'NH-CONHPh ; ab-va- 
liryhrthotolfUkiocarbamidi, BaCONH*CS'NH^.To ; 
sym. vaUffiorthotolylufia ; ah-vaUrylparatolyUkiocarba- 
midg, Ba-CONH'CS'NH-^-To; vaUryl^ naphtkylthio- 
ciir6amuir,BuCO-NH-CS*NH'a*Napt ; n-vaUryl-vbtHMyU 
pksnylthiourea, PhCHa'N(Pb)-C(SH:NCOBu ; vaUryl- 
thioHna, CSNaHjCOBu ; val^ryl - $ • thumr$thans, 
BaCONH-CS-OCafis ; %h * cinnamoylph§nyltkiocaTba- 
mUs, PhCH:CH'CONHCSNHPb; ah^nnamoylortho' 
tofyUkioearbamidg, PhCH:CH*CONHCSNHo-To; ab. 
cinnamoylparatolylthiocarbamide, — 

PhCH:CH-CONHCS NH-^-To ; 
9h'CiHnamoylalphanaphthyUhiocarbamide, — 

PhCHrCHCONHCS-NHaNapt ; 
ctHHamoylthiourta.^- 

CSNaHa'COCH.CHPh ; PhCH:CHCONH CSOCaHj, 
cinnamoyl p4hiour$than€. All the thioureas above named, 
with the exception of the valeryl benzoylphenyl com- 
pound, are desulphurised by heating with alkaline lead 
tartrate. 

It is proposed to extend these experiments with lead 
thiocyanate, in the hope of obtaining tbiocarbaraides de- 
rived from other adds than those only containing the 
group CO'Cl ; for example, picric, phenylsulphonic, and 
ethyl sulphuric acids. 

128. ** Som$ ConstituiHts of th§ Root of * Polygonum 
euspidatum.' " By A. Q. Pbrkin. 

Polygonum euspidatum is a native of China and Japan, 
and flourishes in parts of India and Russia. The freshly 
gathered roots consist of a thick, succulent bark, of an 
orange-red colour, and a central woody portion of a light 
yellow tint. 

The principal constituent of the root bark was found to 
be a glucoside, CaxHaoOio* crystallising in lustrous yellow 
needles melting at 202—103°. On hydrolysis, this yielded 
61*82 per cent of a produ^ which was recognised as 
imodin, the reaAion— 

CaiHaoOio+HaO-CxsHioOs-l-CeHiaOe 
requiring 62*5 per cent of emodin. This glucoside, for 
which the name cuspidatin is proposed, differs consider- 
ably in properties from frangulin, CaxHaoOg, the glucoside 
of emodin which is contained in tbe bark of the Kkamnus 
frangula, 

A second glucoside was also isolated, but in too small 
quantity for analysis. On hydrolysis it yielded a crystal- 
hne substance melting at 199°, which by treatment with 
■ulphuric acid at 160* was converted into emodin. It 
was found to be identical with the emodin monomethyl 
ether previously isolated from the root bark of VtntUago 
madraspatama (Trans. Chtm. Soc., 1894, 923). The other 
substances found were a small amount of free emodin 
and a wax which crystallised in colourless leaflets melting 
at Z34 — 135^ This latter was found to be identical with 
the wax CisHasO, present in the root bark of the Morinda 
umbtUata {Trans, Chem, Soc, 1894, ^54)* 

An examination is being carried out of the constituents 
of the roots of the Polygonum bistorta and Rumex mpal- 
fusis, which are closely allied to this plant. 

Z29. " Not€ on thi Action of Hydrofluoric Acid upon 
Crystallistd Silicon," By G. S. Nbwth. 

It is generally stated that hydrofluoric acid is without 
adion upon crystallised silicon; that while amorphous 
silicon is attacked by it, this acid is incapable of ading 
upon the crystallised element. 

This statement, however, requires to be made with 
some reservation, for although it is doubtless true of the 
aqueous acid, and possibly of the liquid acid, it is not true 
of^the gas. 

If acid potassium fluoride be heated in a platinum 
retort, and the pure gaseous hydrofluoric acid so produced 
be allowed whilst hot to blow upon a little heap of crys- 



tallised silicon supported on a porcelain crucible lid« the 
silicon at once takes fire and bums brilliantly in the gaa» 
forming silicon fluoride and hydrogen. 

If the neck of the retort be mote than an inch or 
two in length, it is necessary to heat it in order to keep 
the gas sufficiently hot, but if it be quite short, the tem- 
perature of the gas as it is disengaged from iu compound 
is sufficiently high to enable it to attack the silicon. 

The importance of this observation lies in the fad that 
the spontaneous ignition of crystallised silicon is generally 
regarded as in all cases a sufficient test for free fluorine ; 
but it is evident that unless the temperature of the gas is 
below a certain point the combustion of silicon is not a 
safe criterion. 

130. **Notc on th$ Pcriodidis of Thsobroming" By 
G. £. Shaw. 

Apparently only one periodide of theobromine has been 
previously described, viz., that having the formula 
C7H8N40a'HI'l3, prepared by Jorgensen by exposing a 
solution of theobromine hydrochloride, mixed with potas- 
sium iodide, to the air. By varying tbe amounts of 
hydrochloric and hydriodic acids present, the author has 
obtained compounds having the formulae — 

(C7H8N40a)aHI-HCI-Ia and (C7H8N40a)3HI(HCl)aIs. 
and by re-crystallisation of a mixture of the three froin 
weak alcohol containing hydriodic acid and iodine, a auti- 
stance of tbe composition (C7H8N40aHI)a+Ha0 was ob- 
tained. 

A solution of theobromine in saturated hydriodic acid 
deposited on standing crystals having the composition 
(C7H8N40aHI)al3. 

131. ** A Synthtsis of DiphcnyloxytriaMoUng.'* By 
Georob Youno, Ph.D. 

The readion between bencaldehyd and phenylaemi- 
carbazide described in a previous notice {Proc. ClUm. 
Soc.t 1894, 95, 124), and represented by the equation 
C7H9N30-|-C7H60-|-0»Cx4HxxN30-|-2HaO, is shown in 
the present paper to take place in the following two 
stages : — I. C7HgN30 + O - C7H7N3O -I- HaO ; 
II. C7H7N30-|-C7H60«Cx4HxxN30+HaO. The inter- 
mediate produd, C7H7N3O, is phenylazocarbonamide, 
CfiHsNtN'CO'NHa. It is formed immediately by tbe 
adion of ferric chloride in aqueous solution, or potassium 
permanganate in dilute sulphuric acid. It is also 
formed, but very slowly, by the adion of moist air on 
phenylsemicarbazide. It forms red needle-shaped crys- 
tals, m. p. xz4°. The second stage of the above readion 
does not take place so easily when the intermediate pro- 
dud is isolated as when tbe benzaldehyd is added 
to the phenylsemicarbazide before oxidation. In 
the latter case, the whole readioo takes place in boiling 
alcohol ; in the former, the azo-derivattve and the 
benzaldehyd require to be heated in alcohol in a sealed 
tube at Z20° C. The benzoyl-derivative, — 

Cx4HxoN30(C7H50), 
has been prepared, in addition to those previously men- 
tioned, by the adion of benzoyl chloride on diphenyloxy- 
triazoline and its silver salt. It forms flat needles, m. p. 
133-5^ 

132. **Nof€ on Piperovatim." By Wyndham R. 
DuMSTAN, F.R.S., and Francis H. Carr. 

The method previoufily used (Trans., 1895) (orextrading 
piperovatine from Piper ovatum being exceedingly tedious, 
the authors experimented with tbe view of finding a 
better method. The following process is a considerable 
improvement, and with its aid the adive constituent can 
now be extraded and crystallised in the course of a few 
hours. The method consists in percolating with ether; 
the dark- coloured extrad thus obtained is freed from 
ether and the adhering volatile oil, and then extraded 
with hot dilute alcohol (13 per cent) ; on cooling this ex- 
trad, crystals separate, which may be re-crystallised £roffl 
40 percent alcohol. 



i 



CBMIICAI.MtWBtl 

D«c6, X895. I 



Dtbenzaconine and Tetracetylaconine^ 



279 



Forther experiments have been made on the hydrolysis 
of piperoYatine with the small remaining quantity of 
material. A small quantity was heated with water in a 
sealed tube to 160°, with the result that a volatile base, 
probably a pyridine derivative, a substance smelling like 
anisol and giving phenol, on treatment with sodium 
hydroxide, and also an acid were produced. 

X33. ** DibenMaconint and Tttracetylaconine.*^ By 
VTymdham R. Dunstan, F.R.S., and Francis H. Carr. 

The authors having failed so far to produce aconitine by 
the acetylation of benxaconine have tried to form bens- 
aconine by introducing a benzoyl group into aconioe ; 
this, however, has not yet been contrived, but new aconine 
derivatives have been obtained. When equimolecular 
proportions of aconine and benzoic anhydride are dissolved 
together in chloroform and allowed to stand at the or- 
dinary temperature, reaaion occurs with produdion of 
dtbenzaconine. 

DibtHMOConini, Ca4H37(Bz)aNOxoi is unlike aconine in 
being insoluble in water and soluble in ether ; it crystal- 
lises from ether in rosettes of needles, m. p. 265°. I>t- 
btnMactmint hydrobromidi crystallises well from a mixture 
of alcohol and ether, m. p. a6I^ DibenMoconine aurichloridt 
is precipitated by adding a solution of gold chloride to a 
solution of the hydrochloride of the base, and may be 
crystallised in yellow tables from a mixture of alcohol, 
ether, and petroleum, m. p. 212^ This salt contained z8 2 
percent of gold; calculated forC24H37(Bz)2NOxoHAuCl4, 
1871 per cent. Hydrolysis of the base furnished 33*3 per 
cent of benzoic acid ; the calculated quantity for 
Ca4H37(Bz)aNOio is 34-4 per cent. 

By the adion of a large excess of benzoic anhydride, a 
crystalline base, m. p. 190°, soluble in ether and insoluble 
In water, is formed, which has not been further exam- 
ined. Benzoyl chloride dissolved in chloroform does not 
read with aconine even when heated with the base. 

Titracityl'aeonim is formed when a solution of aconine 
hydrochloride and acetyl chloride in chloroform is allowed 
to stand for thirty-six hours at the ordinary temperature. 
It is insoluble in water, but readily soluble in ether and in 
alcohol, from either of which solvents it crystallises in 
small prisms, m. p. I96^ 

On hydrolysis, aconine and 35*2 per cent of acetic acid 
are formed, the formula C24H35(Ac)4NOio demands 35-8 
per cent of acetic acid. 

134. •' MoUadar Volumi Change during th$ Formation 
of DiluU Solutions in Organic Liquids.** By A. Wbnt- 
woRTH Jones, M.A. 

The author has determined the volume changes during 
the formation of several solutions in benzene and carbon 
disulphide, and calculated the molecular volume change 
asrxmxW/VxMxtt»-;t. 

Where v » observed volume change. 



V - 



W- 

M B 

and X a 



volume of solution, 

molecular weight of substance, 

weight of substance taken, 

„ solvent „ 

molecular weight of solvent, 

„ expansion or contradion. 



The values for molecular weights of several ** non- 
associating " liquids are very different, and sometimes 
change their sign, and if the phenomena of these solutions 
In organic liquids are comparable with those of aqueous 
solutions of organic compounds, it is impossible to admit 
that these volume changes are measurements of the at- 
tradion of substance for solvent and equal for molecular 
weights of difi'erent substances, as is stated by Traube 
{Bir., X895, xxviii., 410). 

The author suggests that these volume changes occur- 
ring on solution are of the same nature as the smaller 
changes occurring when a moderately strong solution is 
diluted, and that both are analogous to the deviations 
from Boyle's law observed in the case of gases. 



The following values have been obtained by the use of 
the specific gravity method : — 

Carbon Disuipkidt Solutions 
at 15" C. 



Methyl formate 
Ethyl acetate .. 
Ethyl acetoace- 

tate 

Paraldehyd 
Nitrobenzene .. 
Benzaldehyd . . 
Aniline . • • . 
Benzene . . • . 
Ethyl iodide . . 
Phosphorus tri* 

chloride 



MolecaUr 
expantion. 

0-0797 
0-0809 

0-1072 
0*0972 
0-0349 
0*0305 
0-0310 
0*0320 
-0*0632 



.. -0-09x3 

A contradion occurs in 
the last two. 



BenMtni Solutions at 15** C. 




Molecalar 




expansion. 


Methyl formate 


0*0156 


Ethyl acetate . . 


0*0076 


Ethyl acetoace- 




tate 


0*0120 


Paraldehyd .. 


0*0x41 


Nitrot>enzene .. 


-0*0040 


Benzaldehyd . . 


-0*0042 


Aniline • • • . 


-0-0067 


Carbon disul- 




phide .. .. 


0*0188 


Piperidine 


0*0020 


Phosphorus tri- 




chloride . .. 


0*0041 



A contradion occurs in the 
5th, 6th, and 7th cases. 



NOTICES OF BOOKS. 



Milkt its Natur$ and Composition : a Handbook on the 
Chemistry and Baderiology of Milk, Butter, and 
Cheese. By C. M. Aixman, M.A., D.Sc. Crown 8vq. 
Pp. 180. London : A. and C. Black. 1895. 

A TREATISE en milk, as a commercial article of food, 
without a notice of the baderia which affed its preserva- 
tion, modify its properties, and in some cases serve as a 
mattries morbi, would in these days be rightly set aside as 
comparatively worthless. Dr. Aikman has therefore done 
well to devote a chapter to the baderia of milk, and else- 
where to notice the presence and the influence of micro- 
organisms on butter and cheese. 

We find here, in the first place, an account of the 
strudure of the cow's udder and of the secretion of milk. 
Dr. Aikman refutes the old theory that milk is filtered 
blood. He points out the important chemical difference 
that sodium salts predominate in the blood, whilst potas- 
sium salts are more abundant in milk. 

An important chapter is devoted to the percentage 
composition of milk. A table shows the variation in the 
composition of cows* milk, as determined by different 
authorities. The average of fat in the German samples 
is, according to Fleischman, 3-40; according to Kirchner, 
3*4; whilst in American samples it is 4*00; and in English 
milks the average of 120,540 samples is, according to 
Vieth, 4*10. 

Milk, the author rightly holds, should be defined under 
a Sale of Foods Ad as the " normal secretion of the 
mammanr glands of the cow, and that a person selling 
abnormal milk should be treated as a sophisticator." 

The official standard in England is only 3 per cent, 
whilst in Massachusetts it is 3*70, in Vermont 3*25, and 
in Philadelphia 3*50. 

The three largest mineral constituents found in milk 
are potash, lime, and phosphoric acid, each forming from 
20 to 26 per cent of the total ash. 

The fat in the milk of different herds of cows varies no 
little. In the milk of short-horns it is 3*73, in Jerseys 
5*02, in Guernseys 4*90, and in Ayrshires 4*15. We have 
not been able to meet with an analysis of a trustworthy 
specimen of the milk of Lancashire long-horns, but we 
believe it is at least as rich in fat as that of the Ayr- 
shires. 

Dr. Aikman does not accept the view that the richness 
of a milk in fat is shown by the depth of the layer of 
cream. He rejeds the belief that thunder turns milk 
■our. 



28o 



Chemical Notices from Foreign Sources. 



1 Dec. 6, x8q5- 



On the importaoce of cletnlineti in every department 
of the milk trade the author intiiti most emphatically, 
thowing how the hands of milkmen, the teats of cows, 
and the milk pails become rapidly contaminated. 

The importance of milk as a vehicle of various diseases 
is carefully shown. Tuberculosis, typhus, diphtheria, and 
cholera are thus conveyed. According to Hart, of fifty 
epidemics of typhus investigated in England, twenty-eight 
were traced to infeded milk. 

We cannot prolong our survey of this valuable work, 
but we can conscientiously recommend it to all persons 
conneAed with the milk industries. 



Thi Handling of Dangtrous Qoodt : a Handbook for the 
Use of Government and Railway Officials, Carriers, 
Shipowners, Insurance Companies, Manufadurers and 
Users of such Goods, and others. By H. Joshua 
Phillips, F.I.C. F.C.S. Crown 8vo., pp. 362. London : 
Crosby Lockwood and Son. 1895. 

Thb number of substances dangerous from one or other 
point of view which are met with in modem commerce 
18 great. As a consequence, accidents to property and to 
human life are constantly occurring, due sometimes to the 
ignorance or the recklessness of manufadurers and mer- 
chants, and perhaps more frequently to the negligence of 
their servants. Hence Mr. Phillips has done well in pre- 
senting the public with the work before us. He is already 
favourably known to many of our readers by his works on 
** Engineering Chemistry ** and on ** Fuels, their Analysis 
and Valuation," and in his former capacity as consulting 
chemist to the Great Western and Great Eastern Rail- 
ways he has enjoved special opportunities of studying the 
classes of goods here under consideration. 

The first part of the book treats successively of com- 
bustible acids, alkalies, salts, and gases, of coal-tar and 
its produAs, of petroleum and its produds, of fixed oils 
and fats, of volatile oils and of various highly inflam- 
mable liquids, of inflammable solids, of substances liable 
to spontaneous combustion, and of explosives. These 
chapters are exceedingly well written, and, i/ duly studied 
and aded upon by the interests concerned, will be pro- 
dudive of much good. Some substances, however, are 
mentioned which are of little importance, such as 
vasolene. As for roasted and ground coffee, their im- 
portation and carriage by railway, if it ever occurs, is an 
evil ; and as for date-stones and olive-kernels, they should 
never be allowed to be landed. The author does not 
mention ground dye-woods, the storage of which is often 
dangerous. Worst of all substances liable to spontaneous 
combustion are weighted or loaded silks, of which 
Insurance Companies should beware. The methods laid 
down for ascertaining the safety of explosives are those 
in pradical use. 

The Explosives Ad of 1875 is here given at some 
length, together with the comments of Sir F. Abel. In 
some cases the penalties enaded for the offences against 
the provisions of the Ad are unreasonably low. 

The second part of the work narrates a series of acci- 
dents which are well named ** instrudive," and which 
may serve as a salutary lesson to persons who have to 
handle dangerous goods. It appears, from the Bombay 
calamity of 1891, that blasting gelatin is—especially in 
hot climates— liable to spontaneous decomposition. The 
dynamite catastrophe of Santander (1893) seems to show 
that the possible gains derived from high explosives are not 
enough to compensate for their evil results. 

The number of accidents from mineral oil lamps is 
alarming, and it is especially to be regretted that such 
lamps while burning are frequently thrown at each other 
by persons quarrelling. 

The intentional outrages efiPeded in many cases by 
*' Atlas powder A " exhibit a black record. Here, also, 
the perpetrators when deteded too often escape with in- 
adequate punishment. 



The third part of the work gives the special railway 
classification, mode of packing, &c., for the conveyance of 
explosives by goods trains. Some of these classifications 
are open to objedions. 

An Appendix, containing a variety of useful tables, 
concludes the work. 

The '* Handling of Dangerous Goods '* merits a wide 
circulation, and an intelligent, appreciative study. 



Laboratory Manual of Inorganic PnparaHons. By H. 

T. VuLTi and Gborgb M. S. Nbustadt. New York : 

1895. Pp. ii., 180, iii. 12 mo.. 111. 
The authors of this useful handbook observe that the 
study of organic chemistry is usually conduded on a more 
logical plan than that of inorganic, synthetic work pre- 
ceding analytical, and researches, and they propose that 
this work should be placed in the hands of students be- 
fore they begin the study of analytical chemistry. It 
shows '* how compounds, often very complex in charader, 
rare in occurrence or expensive in preparation, may be 
produced from simple substances, or from those which 
are comparatively plenty and cheap, and how the bye- 
produds may be saved.'* The substances to which the 
attention of the student is direded embrace water (am- 
monium-free), ethyl-alcohol, oxygen, hydrogen, nitrogea, 
chlorine, hydrochloric acid, nitric acid, nitrous oxide, and 
after several other mineral acids and oxides, compounds 
of calcium, lead, bismuth, of the alkalies, &c., as well as 
hydroxylamine, hydrazine, chydrazaine, and carbonoxy- 
sulphide. 

The instrudions for preparing all these substances are 
clearly worded ; perhaps the quantities taken are unne- 
cessarily large in some cases, but this is a minor fault. 
References to original papers are often introduced, and 
equations expressing readions are generally given when 
advisable. 

In certain instances it is difficult to understand the 
reasons for seleding a given substance for study ; but this 
remark would apply to any work of similar charader, an- 
less the reviewer happened to be the author as well. 

The authors generally place the chemical formula off 
the substance under discussion at the head of each sec- 
tion, but not uniformly ; they have taken pains to inform 
the student that hydrochloric acid has the formula HCl, 
but they negled to inform him as to the composition of 
hydrazine, and of platinoso-chlorides, bodies presumably 
less known. 

The work has an index, but lacks a table of contents. 

The first-named of the authors has had experience in 
teaching large classes in the School of Mines, Columbia 
College, and undoubtedly knows the needs of students 
beginning the study of chemistry. 

The handbook can be cordially recommended. — 
H. C. B. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

NoTB.— All degrees of teroperAture are Centigrade ooleM otherwiM 
expreMed. 

Compits Rmdus Htbdomadaires dts Siafues, de VAcademU 
des Sciences, Vol. cxxi.. No. 20, November xx, X895. 
On Tempering Extra-Hard Steels.— F. Osmond. — 
If we take an ingot of steel carburetted by cementation in 
which the proportion of carbon varies in a continuous 
manner from end to end (say from X'yo to 0*35 per cent), 
submit it to very energetic tempering, and then try with 
a sewing needle to scratch a polished surface, we find, as 
might be expeded, that the needle scratches the softest 



Cbbmical Nbw8, I 
Dae 6, 1895. f 



Chemical Notices from Foreign Sources. 



281 



parti up to about 070 per cent ; the mark is then inter- 
rupted, but, contrary to all received ideas, it re-appears 
when the proportion of carbon exceeds z'30 percent. On 
examining this scratch in the most highly carburetted 
parts with the microscope it is found to be not con- 
tinuous, but presents frequent interruptions. The region 
in question is therefore not homogeneous, and contains at 
least two constituents which we may call A and B. A, 
which is not scratched bv tne needle, scratches glass and 
orthose ; B is scratched oy apatite and perhaps by fluor- 
spar. A has a slight greyish tint, whilst B is of a silvery 
whiteness. 

On Nickel and Cobalt Silicidet.— M. Vigouroux. 
— M. Moissan has recently made known the adion 
of silicon upon iron, chromium, and silver. The author 
now describes nickel and cobalt silicides obtained in a 
similar manner. These silicides have a distindly metallic 
asped and a steel-grey colour perfedly crystalline. Nickel 
silicide has a specific gravity of 7*2 at 17° ; cobalt silicide 
is yi at the same temperature. They are more easily 
fusible than silicon or than the pure metals, but they resist 
the highest temperatures without decomposition. Fluorine 
attaclu them with incandescence at the ordinary tempera- 
ture. In dnr chlorine they burn with incandescence at a 
red heat. The composition of the nickel compound is 
SiNia, and that of the cobalt silicide is analogous. 

On the Alcoholatea.— H. Lescoeur.— The author de- 
scribes the compounds CaHcNaO.aCaHfiO, CaH5NaO, 
NaHO.CaHeO, and NaHCaCaHfiO. 

Properties of the Bmulaine of Mushrooms.— Em. 
Bourquelot and H. H^rissey.— One and the same emul- 
sine appears to exist in the mushrooms, but we have as 
yet no evidence that it differs from the emulsine of 
almonds. 

Constancy of the Congelation-point of some 
Liquids of the Organism.— J. Winter. — As regards 
milk the constancy of its congelation-point seems to me 
to afford a simple and certain check on its state of purity. 
This study reveals to us a novel and unknown fundion of 
the blood-globules or of the fibrine. 

Fermentations induced by Friedland's Pneumo- 
Bacillus. — L. Grimbert. — The author's pneumo- 
bacillus differs from that of Frankland by its property of 
attacking glycerin and dulcite, by the nature of its fer- 
mentation-produds, and by the energy of its aAion. 

Diredt Fixation of certain Metallic Oxides by Vege- 
table Fibres.— A. Bonnet.— The author finds that the 
copper, zinc, cobalt, and iron (ferric) hydroxides may be 
diredly fixed upon vegetable fibres in conditions similar 
to those observed with the lead oxides. 



Zeitschrtft fur Anorganische Chemie, 
Vol. viii., Part 6. 

Occlusion of Barium Chloride by Barium Sul- 
phate.— T. W. Richards and H. G. Parker.— The occlu- 
sion af barium chloride by barium sulphate occasions 
considerable errors. The occlusion is greater in concen- 
trated than in dilute solutions, greater In presence than 
in the absence of hydrochloric acid, and greater if the sul- 
phate is added to the btrium than in the inverse case. 
In the ordinary conditions of careful precipitation in 
presence of a slight quantity of free acid, the error occa- 
sioned by occlusion is nearly compensated by the solu- 
bility of barium sulphate in water or acids ; this solubility 
must be taken into account in careful determinations. 
The error occasioned by occlusion can be corrected with 
great accuracy if the chlorine retained by the precipitate 
is determined and the corresponding weight of barium 
chloride is deduded from the total weight of the precipi- 
tate. 

Colour, Specific Gravity, and Surface Tension of 
Hydrogen Peroxide.— W. Spring.— Hydrogen peroxide 



is a liquid of the same colour as water, though of a darker 
shade. Its specific gravity is 1*4996 and its surface tension 
smaller than that of water by more than one-half— 3*583 
as against 7750. The colour which is shovm by oxygen, 
in a higher degree by ozone, reappears in water and in 
hydrogen peroxide. All the fads seem to show that in 
HaOa the oxygen has lost its charaAeristic attributes to a 
less extent than in HaO. In a word, hydrogen peroxide 
seems in a chemical point of view to be rather a non- 
saturated compound between Oa and Ha than a true 
atomic compound. Hydrosen peroxide in a pure dry 
state decomposes no less violently than nitrogen chloride 
or nitro-glycerin. 

Atomic Weight of Molybdenum.— Karl Seubert and 
William Pollard.— The authors find from molybdenum 
trioxide by the acidimetric process Mo s 95 729, and by 
the reduAion of the trioxide to metal Mo s 95 •735. The 
results of Dumas, Debray, Liechti and Kempe, Smith and 
Maas, and Seubert and Pollard yield a mean of 95*77, or 
if he bear in mind the uncertainty of the second decimal, 
Moa95*8. 

Heavy Metallic Salts of Bichromic Acid.— Gerhard 
Kriiss and Oskar Unger.— The authors did not succeed in 
obtaining bichromates of the heavy metals in a definite 
form, but were merely able to produce crystalline double 
Saks of metallic and alkali bichromates. The bichromates 
of the heavy metals are in general not capable of crystal- 
lisation. 



BtUleHn de la Sociiti d* Encouragenunt pour P Industrie 
NationaU. Series 4, Vol. x.. No. ii8« 

The Smokeless Pyro-collodion Powder of Prof. 
Mendeleeff.^This lengthy paper does not admit of ab- 
stradion. It concludes with the well-known diAum : Si 
vis pacem para bellum. 

Industrial Preparation of Liquid Air and Oxygen 
by means of the Linde Process.- This memoir requires 
the accompanying figures and the table of curves. 

Tar of Naphtha.— This paper does not admit of useful 
abridgment. 



MISCELLANEOUS. 

Royal Society.— The following President, Officers, and 
Council were eledted on November 30th last :— 

Pr»sidtn%—^\t Joseph Lister, Bart., F.R.C.S.. D.C.L. 

TT$aiurer—%\x John Evans, K.C.B., D.C.L., LL.D. 

Sicretaries—FtoL Michael Foster, M.A., M.D.; The 
Lord Rayleigh, M.A., D.C.L. 

Fortign Sicntary^Edwud Frankland, D.C.L., LL.D. 

OthiT Mimbtrs of tht Comm^i/ — William Crookes, 
F.C.S.; Sir Joseph Fayrer. K.C.S.I. ; Lazarus Fletcher, 
M.A. ; Walter Holbrook Gaskell, M.D. ; William Hug- 
gins, D.C.L. ; The Lord Kelvin, D.C.L. ; Prof. Alex- 
ander B. W. Kennedy, LL.D.; Prof. Horace Lamb, 
M.A. ; Prof. Edwin Ray Lankester, M.A. ; Proil Charles 
Lapworth, LL.D.; Major Percy Alexander MacMahon, 
R.A. ; Prof. Jonn Henry Poynting, D.Sc. ; Prof. Arthur 
William Rucker, M.A. ; Osbert Salvin, MA.; Prof. 
Harry Marshall Ward, D.Sc. ; Admiral William James 
Lloyd Wharton, C.B. 

Royal Institution. — The following are the Ledure 
Arrangements before Easter : — Professor John Gray 
McKendrick, Professor of Physiology in the University of 
Glasgow, Six Ledures (adapted to a juvenile auditory] 
•* On Sound, Hearing, and Speech'* (experimentally illus- 
trated) ; Professor Charles Stewart, Fullerian Professor of 
Physiology, R.I., Eleven Ledures on **The External 
Covering of Plants and Animals: its StruAure and 
FunAions '*; The Rev. Philip H. Wicksteed, Four Ledures 



282 



Meetings for the Week. 



fOBSaUCALllMfl, 

1 D«.6,ia». 



on •• Diuite " ; ProfesMr H. ManhaU Ward, ProfeMor of 
BoUny in the UniTertitr of Cambridge, Three Ledarea 
on •• Some Atpeda of Modern Botany" ; The Rev. Wil- 
liam Barry, D.D., Foor Ledarei, ** Masters of Modern 
Thought " — Voltaire* Rovsseao, Goethe, and Spinoza ; 
Professor C. Hubert H. Parry, Professor of Musical His- 
tory and Composition at ithe Royal College of Music, 
Three LeAores on '* Realism and Idealism to Musical 
Art '* (with musical illostrations) ; The Right Hon. Lord 
Rayleigh, Professor of Natural Philosophy, R.I., Six 
Lednres on *' Light." The Friday Evening Meetings will 
begin on January zyth, when a Discourse will be given by 
the Right Hon. Lord Rayleigh, on ** More about Argon." 
Succeeding Discourses will probably be given by Professor 
Burdon Sanderson, Mr. W. S. Lilly, Dr. John Murray, 
Mr. J. J. Armistead, Dr. Edward Frankland, Mr. A. R. 
Binnfe, Mr. Sidney Lee, Professor T. R. Eraser, Profetsor 
Dewar, an d other gentlemen. 

MEETINGS FOR THE WEEIL 

Monday, 9tb.~8ocietir of Aru, 8. '- If echaoicsl Roftd Carriages," 
hf H. Worby Beaamoot, M. Inat.C.E. (Oaator 
LeAnrcs). 

WaoHBSDAY, iitb.- Society of Arte. 8. Ad(oomed Discauion oo 
Iff. Oooyncnane's Paper oo ** Locomotive 
Csrrisces for Common Roede." 

FaiDAY. isth.— Pbyeical, 5. ** A Mechanical Device for Performing 
the Temperature Correaiont of Barometert," by 
Dr. John Shield. '* On the Existence of Earth> 
Air Elearical Oarrenu,** by Prof. A. W. Rucner, 
P.R.S. 



ACETONE — Answering all requirements. 

JiiC?TT> .A-OETIO— Puw*^ •nd sweet. 

— BOE»-A-OIO— Cryst. and powder. 

OITIRICHCryat. made in earthenware. 

Q.-A-X1X1IO— Prom beet Chinese gallt, pure. 

S-A-XiIOlTXilO— By Kolbe's process. 

^^ T-A- JCT JCTIC— Po*" Pharmacy and the Arte. 

LIQUID CHLORINE 

(Compressed in steel cylinders). 

FORMALIN (40)t CHaO)-Aniiseptic and Preservative. 

POTASS. PERMANOANATE-Cryst., large and small. 

8ULPHOCYANIDB OF AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THE ARTS 

Wholesale Agents— 

A. & M. ZIMMERMANN, 

6 A 7, GROSS LANE LONDON. E.G. 



PETROLEUM JELLY, 

PARAFFINUM MOLLE, B.P. 
(PIONEER BRAND) Registered Trade Mark. 

Equal to and Cheaperthan VASELINE. 

FOR MEDICAL AND PHARMACEUTICAL PURPOSES. 

WuiTB, Yellow, Vbtbrinary, and Waterproof. 

All kinds put tip in i-lb., 5-lb., 7-lb., 14-lb., 28-lb., and 
561b. Patent Tins, and in 300.1b. Barrels. 



Sind for SampUs and Pric4s to 

GRIHDLfcY AID CO.,LIM., POPUR LONDON, E. 
(EatiOiliidied 1868). 



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_1 



CnsMicAL News. ) 
Dec. 13, 1895. 1 



Gases obtained from the Mineral Eliasite. 



283 



THE CHEMICAL NEWS 



Vol. LXXII.. No. 1881. 



ON THE GASES OBTAINED FROM THE 
MINERAL ELIASITE. 

By J. NORMAN LOCKYER, C.B., F.R.S. 

Observations have been made of the gases obtained 
from ihe mineral eliasite heated in vacuo, in the manner 
which I have descril^d in a former paper {Roy, Soe, Proc, 
Iviii., p. 68), and, in addition to hnes of known gases, 
others have been noted, fur which no origins can be traced, 
at the following wave-lengths : — 



An^^uom. 
6l21'2 
6064-5 
59900 

5»74*9 
58457 
54288 
5403' X 



Rowland. 
6l22'4 
60657 
5991-6 

58759 (D3) 
5846-8 
54299 
5404- 1 



The wave-lengths of these lines have been determined 
by means of a Sieinheil speAroscope having four prisms, 
comparisons being made with adjacent metallic lines, and 
the positions interpolated by micrometric measurements ; 
the accuracy may perhaps be taken to be within o*x tenth 
metres. Other lines have been noted, but they are not 
' included ta the list, ior the reason that their wave-lengths 
have not yet been determined with the dispersion stated 
above. 

Of the lines in the foregoing list, six are in all proba- 
bility coincident with chromospheric lines, as shown 
In the following table, whichralso indicates the frequencies 
and brightnesses of the lines according to Young: — 



WQve length ofChromosphiric Lines, 



(AQg«tr5m't 
scale). 

6xaz'2 
6o6^*5 

5990-0 
58749 (Da) 
5428-8 
5403 I 



(Rowland's 
scale). 

6122*4 
6065-7 
59916 
58759 
5429-9 
54041 



Frequency. 

5 
5 

xo 

100 

8 

5 



Brightness. 

3 

2 

4 
90 

3 
3 



It is important to point out that all these lines do not 
appear in the speArum at the same time. For instance, 
in the first two specimens of the mineral no trace of D3 
was noted, but in the third portion examined, all coming 
from the same specimen, D3 appeared as a pretty bright 
line. Again, as in the case of a previous operation on 
broggerite {Roy. Soc, Proc. Iviii., p. 194), in one experi- 
ment with eliasite the produds of distillation, colleAed in 
four stages, gave difiPerent spedra. 

These fadts seem to indicate that the gas obtained from 
eliasite is either a compound or a mixture of gases, just 
as is that obtained from broggerite according to former 
experiments. 

It is also to be remarked that among the lines in the 
eliasite spedrum, those at 6x22*4 and 6065*7 have been 
recorded in the gases obtained from cl^veite, and 6122*4 
has also been noted in the gas obtained from gummite. 

It seems to me more than probable, therefore, that the 
lines observed in eliasite indicate a new gas, in some way 
associated with those given off by cliveite and brdggerite, 



• A Paper read before the Royal Society, November 21, 1895. 



and the fad that D3 is not necessarily present in the 
spedrum furnishes an additional argument in favour of 
the view that the gas obtained from cT^veite or brdggerite 
is complex. 



THE HISTORY OF MOND»S NICKEL 

EXTRACTION PROCESS.' 

By LUDWIG MONO. 

In the present paper I give an account of the history of 
my process of extrading nickel from its ores, as an in- 
stance of an investigation undertaken in pursuit of pure 
science, which has led unexpededly, in a few years, to an 
important industrial application. I have often been asked 
by scientific men how I came to discover nickel carbonyl, 
and can now explain. Soon after I had satisfied myself 
that the ammonia soda process was far cheaper than the 
Leblanc process for producing carbonate of soda, it be- 
came evident to me that a time would come when the 
Leblanc process would produce carbonate of soda, as a 
by-produd of the bleaching powder manufadure, which it 
would have to dispose of at any price it would fetch. I 
therefore undertook a series of experiments, with the 
objed of producing bleaching powder as a by-produd of 
the ammonia soda process. You all know that the usual 
form of this process consists in treating a solution of 
common salt in which caustic ammonia has been dissolved 
by carbonic acid, with the result that bicarbonate of soda 
is precipitated, while a solution of ammonium chloride is 
formed. In the ordinary course of things this solution of 
chloride of ammonium is distilled with caustic lime, 
yielding gaseous ammonia, which returns to the process 
and a solution of calcium chloride. Other investigators 
had endeavoured to produce chlorine from the chloride of 
calcium obtained by evaporating these solutions ; others 
have proposed to substitute magnesia for the lime in dis- 
tilling the solution of ammonia chloride, and to produce 
chlorine or hydrochloric acid from the MgCla obtained by 
evaporating its solution. I gave my attention to pro- 
ducing the chlorine dired from the ammonium chloride, 
separated from the solution in which it is originally ob- 
tained by refrigeration. 

Ammonium chloride when vapourised is, as is well 
known, dissociated into ammonia and H4CI ; thus, if the 
vapour of NH4CI is passed over a metallic oxide, this 
oxide is converted into a chloride and the ammonia passes 
on altogether with the steam formed by the readion. 

I found that nearly all metallic oxides, with the excep- 
tion of the alkalies and alkaline earths, and that even a 
large number of metallic salts, were aded upon in this 
way by NH4CI vapour, and that a large number of the 
metallic chlorides so formed would give up their chlorine 
by re-converting them into oxides by submitting them to 
the adion of the air at a suitable temperature. I found 
that, of all the substances investigated, oxide of nickel 
yielded the best results, and that the next best were ob- 
tained by magnesia mixed with a certain amount of 
chloride of potassium. 

In developing this process I had to construd a plant for 
volatilising NH4CI, which I found an extremely difficult 
problem, as the vapour of this substance not only ads on 
oxides and salts, but also violently attacks the large ma- 
jority of metals. I succeeded in lining iron vessels with 
glazed tiles in such a way that they would withstand this 
adion, but I required valves for changing from the current 
of ammonium chloride vapour to hot air, and via v$rsa^ 
which had to be very tight to prevent a large loss of am- 
monia. I found that nickel was one of the few substances 
suitable for the construdion of these valves, and that it 
was not at all attacked by ammonium chloride vapour. 



• A Dstrad of Paper read before tbe New York sedion of the Sodstjr 
of Chemical Industry. 



284 



Chemical Researches and Spectroscopic Studies. ^^^oSS^IiiS*' 



These worked perfeAly on a Uboratoiy scale, but whea 
applied on a manufaAuring scale they became leaky, and 
the faces became covered with a bltck crust, which on 
examination was found to contain carbon. The source of 
this carbon seemed mysterious ; the only difference be- 
tween the work on the small scale and that on the Urge 
was that on the small scale we swept the ammonia out of 
the apparatus before admitting the hot air by means of 
pure COa, while on the large scale we used the gases from 
the lime-kiln containing a few per cent of CO. We found 
nickel to have the remarkable property of splitting off 
carbon from CO at a moderate heat, transforming it 
into COa. 

In the course of the experiments finely divided nickel, 
formed by reducing nickel oxide at 400^ C. by hydrogen, 
was treated with pure CO in a glass tube at varying tem- 
peratures for a number of days, and was then cooled down 
tn a current of CO before it was removed from the tube. 
In order to keep the poisonous CO out of the atmosphere 
of the laboratory we simply lit the gas escaping from the 
apparatus. To our surpnse we found that, while the ap. 
paratus was cooling down, the flame of the escaping gas 
became luminous, and increased in luminosity as the 
temperature got below 100^ C. On a cold plate of porce- 
lain put into this luminous flame, metallic spots were 
deposited, similar to the spots of arsenic obtained with 
the March apparatus, and on heating the tube through 
which the gas was escaping we obtained a metallic mirror 
while the luminosity disappeared. Upon examination of 
the mirrors we found them to consist of pure nickel. As 
it seemed improbable that so heavy a metal as nickel 
should form a readily volatile compound with CO we 
purified our CO as perfeAly as possible, but still obtained 
the same results. 

We now endeavoured to isolate this curious and inte- 
resting substance by preparing the nickel with great care 
at the lowest possible temperature, and treating it with 
CO at about 50" C, and thus we greatly increased the 
amount of the volatile nickel compound in the gases 
passing through the apparatus. We observed the excess 
of CO by cuprous chloride solution, and thus obtained a 
residue of several c.c. containing the volatile nickel com- 
pound mixed with a little nitrogen. By passing this gas 
through a heated tube we separated the nickel and ob- 
tained an increased flame of gas, and found in this a 
Siuantity of CO corresponding to about four equivalents 
or one equivalent of nickel. By further improving our 
method of preparing the finely divided nickel, and by 
passing the resulting gas through a refrigerator cooled by 
snow and salt, we at last succeeded in liquefying this 
compound, and were able to produce it with ease and 
facility in any quantity we desired. 

This nickei carbonyl is a colourless liquid, boiling at 
43** C, and which solidifies at -25' C, forming needle- 
shaped crystals. It is soluble in alcohol, petroleum, and 
chloroform ; it is not aaed upon by dilute acids or alkalis, 
and can be readily distilled without decomposition. But 
on heating the gas to 150^ C, it is completely dissociated 
into its components, pore CO being obtained and the 
nickel being deposited in a dense metallic film upon the 
sides of the vessel in which it is heated. 

After continued investigation I came to the conclusion 
that it ought to be possible to make use of the ease with 
which nickel is converted into a volatile gas by CO for 
separating nickel from cobalt and other metals on a manu- 
faAuring scale, and for obtaining it in a very pure state. 
We have now succeeded in producing nickel at the rate of 
li tons per week, from the Canadian nickel matte im- 
ported into England. We ereded a plant near Birming- 
ham fur this purpose. This matte, which contains about 
40 per cent nickel and an equal quantity of copper, is 
carefully roasted, to drive out the sulphur as far as pos- 
sible, and is then subjeAed to the aaion of hydrogenous 
gases, either water gas or producer gas rich in hydrogen, 
in an apparatus which is called the " reducer," the tem- 
perature of which is under perfed control, so that 400^ C. 



is never exceeded. Prom this apparatus the substance 
which is now reduced to the metallic state is taken, 
through air-tight conveyors and elevators, into another 
apparatus called the " volatiliser,'* in which it is subjeded, 
at a temperature not exceeding 80® C, to the adionof CO 
gas. This apparatus consists of an iron cylinder divided 
into numerous compartments by shelves, and provided 
with a stirring device which moves the material nrom the 
top to the bottom, while the CO gas passes through in an 
opposite diredion. The CO gas, which should be as rich 
as pradicable, we prepared by passing pure CO3 through 
incandescent coke ; the pure COa we make by passing the 
flue gas of a boiler or of a fire through a solution of car- 
bonate of potash, and subsequently boiling the solution. 
The CO gas, charged with nickel carbonyl leaving the 
volatiliser, is passed through a series of tubes or chambeis 
heated to about 180* C. in which the nickel is deposited 
in various forms, according to the speed of the gas cur- 
rent, the richness of the gas, and the existing temperature. 
The CO gas, thus almost completely free from the nickel, 
is taken back by means of a blower into the volatiliser, 
where it takes up a fresh quantity of nickel, and is coo- 
stantly used over and over, so that the quantity consumed 
is limited to the very small amount of unavoidable loss 
through leakage of the plant. 

The material under treatment is repeatedly dumped 
from the volatiliser to the reducer, and via vsrsat by 
means of air-tight conveyors and elevators, until the 
amount of nickel volatilised begins to fall off. It is then 
roasted again, to remove the sulphur which it still con- 
tains, and is treated by sulphuric acid to dissolve part of 
the copper. The remaining mass, containing all the 
nickel, some copper, and the other impurities of the matte, 
is again subjeded to the previous treatment until the 
nickel has been extraded as far as pradicable, and the ul- 
timate residue, still containing a few percentage of nickel, 
is melted up into matte again. 

If the nickel is allowed to deposit slowly, at a carefully 
regulated temperature, it can easily be obtained from the 
gas as a coherent metallic flim, so that it is possible to 
coat any substance which can stand heatine to 150* C. 
with a perfed covering; of metallic nickel, and luso to make 
articles of metallic nickel for dired use. 

Hollow nickel goods can be made in this way, which at 
present either cannot be made at all or only by the use of 
very powerful hydraulic machinery, and this will give a 
great impetus to iht manufadure of nickel utensils for 
domestic purposes, the use of which is so very desirable 
from a sanitaiy point of view. The cost of the process, 
if carried out on a sufficiently large scale, is inconsider- 
able. — Enginiiring and hiining JoumaL 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 
STUDIES OP VARIOUS ELEMENTa 

By JEAN SBRVAIS STAS. 
(Continaed from p. 376). 

Chaptbr III. 

Chemical Rbsbarchbs on thb Chloriob. Culx>ratb, 
Perch loratb, and Chloroplatinatb of Potas- 
sium.* 

Introduction, 

AccoRDiNO to my experience up to the present, the mole- 
cular weight of chloride of potassium does not agree with 
Prout's hypothesis. Does this depend on the fad that 
the atomic weight of potassium is not a simple ratio of 
that of metallic silver which is used as the standard for 
comparison ; or is it rather due to accidental impurities 
which might be in the chloride tested; oris it, lastiyt that 

• Tbia research was commencod in the month ol Decefflber, 18A 
and completed in 188a. 



Cbbmical Nbws. I 
Dec 13, 189s. I 



Chemical Researches and Spectroscopic Studies. 



2^5 



poUitiam it not an element ? Sacb it the problem I 
endeavoured to tolve by re*opening the ttady of chloride 
0/ potattiom, which had already been the tubjed of 
kmgthy invettigationt on my part. 

In my Niw rtstarchts on tht laws of ehunieal propor^ 
tions I taid ** I mutt admit then that I could not prepare, 
try meant of chlorate of potattium, a chloride which I 
coold contider abtolutely pure." In fad, after having 
tttccettively eliminated the foreign mattera contained in 
the poreat chlorate of potastium, I deteded, in the 
chloride made from it, the pretence of ailicon in the form 
of tilica and alkaline tilicates, and amongtt them tilicate 
0/ tedium in varioua quantitiet according to the conditiont 
under which the chloride wat produced. The total weight 
of tilica and alkaline tilicatet wat at much at x-2o,oooth 
of the whole. When changing thit chloride into chloro- 
platinate of potattium, I wat able to decreaae to one-half 
the weight of the retidue left by volatiliting chloride of 
potattium. At far at regarda the tilica and alkaline tili- 
catet, the minimum limit wat then i-40,oooth of the 
whole* It wat impottible for me to tell exadly the quan- 
tity of todium exitting in the chloride, or even the ttate 
in which the whole of thit metal exitted. I have alwayt 
believed that the bulk wat in the form of a tilicate. 
Farther on I thall give the reaton for thit opinion. From 
my experience I can ttate that it it not alwayt in the 
form of todium chloride. In fad, by uting a tilver talt, 
it it pottible, and even eaty, to atcertain the presence of 
l-zo,oooth part of chloride in a tolution of chlorate or 
perchlorate of potastium in pun water. Now, a tolution 
of tbete taltt in abtolutely pure water, which, on tpedrom 
analytit, givet pertittent and ttrong indicationt of the 
pretence of todium, remaina abaolutelv clear, and, when 
expoted to MghttProUcttdfrom atmospheric dust, remaint 
colonrlett, after having received a proper amount of nitrate 
or tolphate of tilver, — a phenomenon which it it not pot- 
tible to obtain with a tolution of chlorate or perchlorate 
containing i-xo,oooth of thete taltt. Bunten, moreover, 
hat shown that tpedrum analytit ditclotet an amount of 
chloride of todium 300,000 timet lest than that thown by 
atang tilver taltt. The failure of chemittt to procure, by 
cryttallitation or otherwite, potattium taltt which do not 
ahow the potattium line when volatiliaed in a colourlett 
ftame or in an eledric tpark, hat led Mr. Lockyer to be- 
lieve in the tplitting up of potattium into todium and 
another metal. I do not altogether agree with thit hypo- 
tbesit ; the work I describe farther on it for the purpose 
of seeking what foundation it can have on fad, at much 
with regard to potattium at to other bodiet, toch at 
htbinm, calcium, ttrontium, barium, thallium, tilver, 
mercury, platinum, iridium, ftc. Whilat admitting the 
postibility of procuring chloride of potattium abtolutely 
ttee from todium, tilica, alkaline tilicate, and all other 
known forei|{n bodiet, what guarantee have we that the 
metal contained in it it truly an element ? 

When regarding it from the ttandpoint of experience 
adoally acquired, there are at many reatont for con- 
sidering the metallic bate of thit chloride to be an element 
as there are for considering the hydrogen in hydrochloric 
tcid to be an ondecompotable body. In thort, the com- 
binationt and decompotitiont of the metal uted in the 
vsadiont are alwayt done in tuch a manner at to re- 
produce a body identical with ittelf, when tubmitted to 
chemical forcet,— quite at powerful, in a different way. at 
pbytical forcet,^xadly the tame at hydrogen, no more, 
no lett. The chloride from chlorate, and the chloride 
from chloroplatinate of potattium, though formed under 
very different conditiont, are identical in all their proper- 
tiea. By my previout work I know that potastium, 
though it may form a chlorate, chloroplatinate, nitrate, or 
tartrate of potaatioro, it the tame ; it is repretented by a 
consiemt. I think I am right in concludins, with mott 
chemittt, that potattium it at much an undecompotable 
body aa hydrogen. 

Witbing, however, to tnbmit thit condution to a new 
proof, 1 have had recourte to a tecond method of invetti- 



gation. Before publishing, I beg to tay that I had no 
confidence in the tuccett of my undertaking. The aearch 
for knowledge and truth hat throughout influenced my 
work. 

If the metal contained in the chloride of potattium, 
formed by the dittociation of pure chlorate by the adion 
of heat, be a timple undecompotable body, it teemed to 
me that, when tubmitting the chlorate to the adion of 
heat, in tuch a manner at to reduce it partially into oxy- 
gen, chloride, and perchlorate of potattium, the propor- 
tion of chlorine to metal ought to be invariably the tame 
in the chloride and in the perchlorate formed timulta- 
neously with a timilar chloride. The chloride which wat 
made by the formation of perchlorate, and the chloride 
given off by the subsequent decompotition of thit per- 
chlorate, ought to be identical in every resped. 

If, on the other hand, the metallic base of pure chlorate 
of potassium it a compound body, capable of being tplit 
up, the chloride and the perchlorate made by the dittoci- 
ation of pure chlorate of potattium by the adion of heat, 
ought to combine chlorine and the metal in different pro- 
pot tions, and the chloride made at the tame time at the 

Krchlorate ought to be different from the chloride made 
, the decomposition of thit perchlorate. 
' At a matter of fad, chemical readiont do take place in 
thit manner when we tubmit chlorate of potattium con* 
taining chlorate of todium to the adion of a tuitable 
heat. When heating chlorate of potattium, mixed with 
5 per cent of itt weight of chlorate of aodium, in a plati* 
num vettel, we find, after complete dissociation of the 
chloratet, nearly all the todium in it in the form of chloride 
of todium, in the resultant chloride of potattium. The 
platinum vessel it tlightly attacked, forming a noticeable 
amount of chloroplatinate of todium, at is alwayt the 
cate when one decompotet chlorate of todium in 
platinum. 

The perchlorate formed at the tame time as the 
chlorides of potattium and todium, containt only potat- 
tium. By a tuitable treatment with alcohol, followed by 
auccettive cryttallitationa, repeated tufficicntly often, in 
platinum vetselt theltered from atmotpheric todium, one 
can make the teparation in tuch a manner at to ob« 
tain, on the one band, chloride of potastium containing 
all the todium, and, on the other, a perchlorate of potaa* 
tium which behaves under spedrnm analysit like all 
potaatium perchlorate which haa been long in contad 
with air, or rather in contad with a todium compound 
more toluble than ittelf, and from which one has elimi- 
nated — by meant of tuccettive cryttallitationt and 
wathingt in alcohol— >the todium talt which wat mixed 
with it. 

Now if the metallic bate of chlorate of potastium, in 
tuch a ttate of purity at I have been able to prepare it, 
it a compound body, one can reaton by analogy inat, by 
a properly regulated heat, the teparation ought to take 
place in such a manner at to concentrate in tbe chloride 
or perchlorate, the whole— or at least a part— of one of the 
components of the metallic bate of the chlorate. 

The chemical constant of bodiet being different, expe- 
rience tbowt that the proportion of chlorine to metal in 
a chloride and a percnlorate ought conteqoently to be 
different, and to be between the limitt of thete con- 
ttantt. For the purpote of atcertaining what the real 
fadt are, I started a long course of investigation. 

I tried first whether it wat pottible to obtain chlorate 
of potastium which would not thow the todium line, and 
would be capable of being made to yield a chloride quite 
free from bodiet, whether tolid or volatile, foreign to itt 
normal compotition. Having had a chance of tucceed- 
ing in thit delicate retearch for a chlorate containing tilica 
and todium in the form of tilicate of potattium and to- 
dium, I subjeded the purified chlorate to the adion of 
heat in such a way as to form at the tame time at the 
chloride : — 

Itt. The greatest pottible quantity of perchlorate. 



286 



Technical Analysis of Cyanide Solutions. 



I CVSMIOAL NBWI, 

I Dec. I3« 1895. 



and. A quantity of perchlorate just sufficient to make 
the chloride necessary for determining its pro* 
portional combination with pore silver. 

I will describe all these researches and the results at 
which I arrived as shortly as possible. 

On thi Mithods usid to BliminaU thg Solid Fonign 
BodUs ginsrally found in Commireial ChloraU of 
Potassium. 

It follows, from sufficiently well-known fads, that 
chlorate of potassium purified by means of successive 
crystallisations to the point of no longer clouding a 10 per 
cent solution of silver may yet contain iron, manganese, 
copper, and silver, and always has in it some sodium, 
aluminium, calcium, and silicon. 

Copper and silver are eliminated at once by the addi- 
tion of a sufficient quantity of sulphide or hydrosulphide 
of potassium to a saturated solution of chlorate at zoo^ 
At first almost all the iron and manganese remain in so- 
lution : they are only precipitated when one keeps the 
saline solution slightly boiling for from fifteen to thirty 
minutes ; but in this state the liquid, which is alkaline, 
perceptibly attacks the porcelain or glass dish in which 
the operation is carried on. 

The salt which crystallises out on suddenly cooling the 
filtered liquid from which the copper and silver have been 
thus eliminated is often slightly tinted pink. This colour 
disappears on carefully washing the salt with a solution 
containing i-ioooth part of hydrosulphide of potassium 
cooled nearly to aero, followed by a wash in pure iced 
water. When losing its colour, the chlorate loses the 
greater part of the iron and manganese, as well as the 
aluminium, sodium, calcium, and silicon. 

On dissolving the salt thus obtained in pure boiling 
water, to saturation, and on adding to the solution a suffi- 
cient quantity of pure hydrosulphide of potassium to give 
it a strong alkaline readion, one obtains, on suddenly 
chilling the filttred liquid, a white, powdery, crystalline 
chlorate, from which a wash in a solution containing one 
thousandth part of hydrosulphide of potassium, followed 
by a second wash in pure iced water, eliminates the re- 
maining iron, manganese, and aluminium, but not all the 
silicon, sodium, and calcium contained in it. On repeat- 
ing the dissolving, crystallisation, and washing a great 
number of times under the same conditions, — that is to 
say, in porcelain or glass dishes, and in tk^ prestmt of air 
containing sodtum and silicon,-~ont can certainly diminish 
to a great extent the proportion of sodium, calcium, and 
silicon in the chlorate ; but it appears to me that at the 
fourth treatment one reaches a limit at which the porce- 
lain or glass dishes, and the surrounding air, supply as 
much silica, sodium, and calcium as the treatment suffices 
to eliminate. 

After the third treatment one is therefore obliged to work 
in platinum vessels of a proper shape, and in air enclosed 
OMd purified. By ading thus, I have been able, by six 
successive crystallisations, of which the last three were in 
platinum, to obtain chlorate quite free from silicon, from 
all solid bodies whatever, and from sodium, provided this 
metal exists entirely in the raw chlorate in the form of 
silicate of sodium, as has been the case in all the samples 
of chlorate, save oii#, supplied to me. If, on the other 
hand, the sodium contained in it is partially in the form 
of sodium chlorate, there is a limit which one cannot 
practically pass, so long as one causes the separation of 
the silica by means of sulphide, or hydrosulphide of 
potassium* or potash, in addiuon to carefully washing the 
trystals with alcohol^ in enclosed air. 

I have tried this method of eliminating from chloride, 
sulphate, and nitrate of potassium, the silicon, aluminium, 
and calcium, which are nearly always met with in these 
compounds when purified by successive crystallisations. 

With proper care, the elimination of these bodies is 
very easy, especially sulphate of poussium. After five 
successive ciystallisations, of which the last three were 
effeded in platinum and in air enclosed and purified, I 



have succeeded in obtaining a sulphate and a nitrate 
which, when warmed with just enough pure sal ammoniac, 
formed a chloride which volatilised without leaving a 
trace of solid residue. This study enabled me to prove 
that after the elimination of silicon, aluminium, and cal. 
cium, the sulphate, nitrate, and chloride still retain 
sodium, the chloride and nitrate in very minute quantitiea, 
the sulphate, on the other hand, in comparatively large 
quantities, — an evident proof that, in the compounds 
submitted to purification, the metal sodium existed 
respedively in the forms of sulphate, nitrate, and chloride. 
I repeat that the use of sulphide, hydrosulphide* and 
hydroxide, to catch the sodium, is only effective pro- 
vided this metal is in the potassium salt exclusively as a 
silicate.* 

I describe farther on, with necessary details, the pre« 
paration of the chlorate, perchlorate, and chloride of 
potassium used in my researches. 

(To be cootinoed). 



ON THE TECHNICAL ANALYSIS OF CYANIDE 

WORKING SOLUTIONS.t 

By W. BETTEL. 

For some time past I have felt the need of some quick 
method of analysis which would in a reasonable time give 
the composition of working cyanide solutions, so that the 
chemist- in-charge, or the foreman, in a cyanide works, 
could trace to its source any irregularity in the working 
of such solutions with a view to its corredion. After 
many fruitless trials I have pleasure in drawing your 
attention to some volumetric processes, which, although 
not all that could be desired, are still sufficiency 
accurate to be used for technical work, and have this 
advantage, that the work may be performed by men wbo 
have not had the advantage of a technical or scientific 
training. I do not lay claim to any novelty in this 
analytical process, it is merely pieced up ftom well known 
analytical methods and chemical readions; but, never- 
theless, I hope it will be useful to those of our members 
who have to examine cyanide solutions. 

It is necessary to state at the outset that my remarks 
have reference to the MacArthur-Forrest working solu- 
tions containing xinc, an element which complicates the 
analysis in a truly surprising manner. Before dealing 
with the analysis proper, I will draw your attention to the 
peculiarities of a solution of the double cyanide of sine 
and potassium, usually written KaZnCy4. As is stated 
in works on chemistry, this cyanide is alkaline to indi- 
cators. Now here lies the peculiarity. To phenolphtha- 
lein the alkalinity, as tested by N/zo acid, is equal to I9'5 
parts of cyanide of potassium out of a possible 130*1 
parts. With methyl-orange as indicator, the whole of 
the metallic cyanide may be decomposed by N/io acid, 
as under: — 

K«ZnCy44.4HCl - ZnCl2+ 2KCI •f>4HCy. 

On titration with nitrate of silver solution the end-readtion 
is painfully indefinite. If caustic alkali in excess (a few 
cc normal soda) be added to a known quantity of potassic 

* I am certain that the ptinciple involved in eliminatinf the eitlca 
and alnmininm always contained in chlorate <rf potatatom crystalliaed 
from pore water, by meana of cryataUitatioos made in water rendered 
alkaUtte by potaah or bydroaalphtde of pocassiom, ta applicable to the 
elimination of the ailica and alaminiam contained in ralphate of ao- 
dium crystallited in pare water. By transforming satphate thns 
parioed, by means of chloride of ammoniam, I have obtained chloride 
of sodium capable of being volatilised witboot leaving a trace of re* 
sidae,~a thing 1 had not previoualy socceeded in doing. In fatore. 
one will be able to ase the proportional combination with ailver and 
chloride of sodium, and ascertain, withonc hypothesia. whether the 
atomic weight of ailver and the molecular weight of chloride of ao> 
dium are integral multiples of that of hydrogeo.— January, 1^9. 

f A Paper read before the Chemical and Metailnrgical Sk>cisty, 
Johannesburg, S.A.R., August, 1895. 



i nitCAI» llBWS« I 

Dec. 13, 1895. • 



Convenient Form of Universal Hand-clamp. 



287 



sine cyanide solution together with a few drops of potassic 
iodide, and standard silver solution added to opalescence, 
the reaaion will indicate sharply the total cyanogen pre- 
aant in the double cyanide even in presence of ferro- 
cyanides. If to a solution of potassic zinc cyanide be added 
a amall quantity of ferrocyanide of potassium, and the 
silver solution added, the flocculent precipitate of what 
I suppose to be normal cmc ferrocyanide (ZnaFeCye) 
appears, the end-rea^ion is fairly sharp, and indicates 19 5 
parts of cyanide of potassium out of the adual molecular 
contents of 130*2 KCy. If, however, an excess of ferro- 
cyanide be present, the flocculent precipitate does not 
appear, but in its place one gets an opalescence which 
speedily turns to a finely granular (sometimes slimy) pre- 
cipitate of potassic sine ferrocyanide, KaZnjfFe^Cyxa. 
This introduces a personal equation into the analysis of 
such a solution, for if the silver solution be added rapidly 
the results are higher than if added drop by drop, as this 
ferrocyanide of zinc and potassium separates out slowly in 
dilute solutions alkaline or neutral to litmus paper. 

This ferrocyanide is decomposed by— 

(a) Potassic sodic, or calcic cyanide, &c. ; 
(6) Potassic or sodic hydrate ; 
(c) Potassic or sodic carbonate ; 
as shown by the following equations : — 

(a) KaZn3FeaCyxa+i2KCy=2K4FeCy6-f-3KaZnCy4. 

(This equation is proved by mixing solutions of potassic 
sine cyanide with one of potassic ferrocyanide, no precipi- 
tate occurs. Potassic zinc ferrocyanide is dissolved by 
cyanide soltition). 
(ft) KaZn3Fe2Cyia+X2KHO-> 

«-2K4FeCy6+3ZnK20a+6HaO. 

(Potassic zinc ferrocyanide is readily dissolved by 
caustic alkali. If potassic (or sodic) zinc oxide in solu- 
tion be added to potassic ferrocyanide no precipitate 
occurs even in absence of free alkali). 
(tf) KaZn3PeaCyia+i2NaaC034-6HaO= 

-2KNa3FeCy6-|- x2NaHC034-3ZnNaaOa. 

(This is similar to the (6) reaaion, with the difference 
that carbonates are converted into bicarbonates). 

I will now draw your attention to the equations in- 
volved in the readion previously described. As the per- 
centage of alkalinity is definite, and consists of a portion 
of potassic cyanide loosely combined with zinc cyanide 
more firmly united with less cyanide than corresponds 



in carbonates and bicarbonates, by reversing the process, 
adding bicarbonate of soda, free from carbonate, to the 
solution to be titrated for hydrocyanic acid and free 
cyanide. This is the one instance where hydrocyanic acid 
turns carbonic acid out of its combinations, and as such 
is interesting. 
2KHC03-hAgN03-|-2HCya 

= KAgCy3+KN03-f>2COa+2HaO. 

I will now proceed to describe the method of analysis. 

X. FY$t Cyantdt, — 50 cc. of solution is taken and 
titrated with silver nitrate to faint opalescence or first in- 
dication of a flocculent precipitate. This will indicate (if 
sufficient ferrocyanide be present to form a flocculent pre- 
cipitate of zinc ferrocyanide) the free cyanide, and 
cyanide equal to 7*9 per cent of the potassic zinc cyanide 
present. 

2. Hydrocyanic Acid.^To 50 cc of the solution add a 
solution of bicarbonate of potash or soda, free from car« 
bonate or excess of carbonic acid. Titrate as for free 
cyanide. DeduA the first from the second result 

-HCy I cc AgN03« Q'^HHS,^ 000829 p. c HCy. 

3. DouhU Cyanides,^ Add excess of normal soda 
(caustic) to 50 cc. of solution and a few drops of a 10 per 
cent solution of KI, titrate to opalescence with AgN03. 
This gives i, 2, and 3. Dedud x and 2BKaZnCy4 as KCy 
less 7'9 per cent. 

A corteAion is here introduced. The KCy found in 3 
is calculated to KaZnCy4. FaAor : KCy (as KaZnCy4) 
Xo'9^93sK2ZnCy4. Add to this 79 per cent 01 total, ur 
for every 92*1 parts KaZnCy4 add 7*9 parts. If this frac« 
tion, calculated back to KCy, be deauded from x, we get 
the true free cyanide (calculated to KCy). 

(To be contioaed). 



A CONVENIENT FORM OF UNIVERSAL 

HAND-CLAMP. 

By PETER T. AUSTEN and W. A. HORTON. 

The various holders and hand-damps nsed for holding 
test-tubes and smaller forms belong, as a rule, to two 
classes. The bite is effeded either by a spring or by 

A 




with KaZnCy4, I venture to propose for provisional adop- 
tion the following equations representing the neutralising 
of KaZnCy4 by acid and silver nitrate respedively : — 

(a) xoKaZnCy4 -1-31101 » 1 

-3HCy-f.3KCl.KZnCya)xo,(KCy),7. 

(h) 2oKaZnCy4-f-3AgN03= I 

-3KAgCya+3KN03-f.2[(ZnCya),o,(KCy),7]. ' 

Here is a point for investigation, as to whether there is | 
more than one definite crystallisable salt containing 
K-hZn-|-Cy, neutral to phenolphthalein, and soluble in | 
water, or whether ZnCya is soluble in a solution of , 
KaZnCy4 and produces neutrality to phenolphthalein. 

For the estimation of free hydrocyanic acid I have made 1 
use of Siebold*s ingenious method for estimating alkalis ' 



pressure exerted by the hand. The difficulty with the 
first class of holders is that the spring is often inconve- 
niently strong for delicate tubes, and not strong enough 
for flasks. The second class often fails when long-con- 
tinued holding is involved, as muscular pressure relaxes 
after a time. 

The following little device was worked out to afibrd a 
convenient holder that should take from nothing up to a 
diameter of an inch and a half, and yet allow a grasp 
which corresponds to the weight of the objeA held, and 
also not tire the hand, no matter how long it is held. 

The clutch b slides on the parallel bars b, and is 
slightly smaller than the counter-clutch A. This, with 
its curvature, allows it to grasp any objea, no matter how 
small, that is placed between B and a. A double bearing, 



288 



Influence of Temperature an Refractive Power. {^IX^.^ST'^ 



to insure ease of movement, it effeded by winding the 
wire at d. Tlie double arch c allowi the thumb to 
press easily and comfortably against it, and ad as a 
knee-joint. The swell o keeps the handle in the grasp, 
and the rubber strap f brings the travelling clutch back 
and opens the clamp as soon as the pressure is removed 
from c. 

To nse the apparatus, the handle is securely grasped 
and the end of the thumb is placed against c. On 
straightening the thumb, in the manner of a knee-joint, 
the objed is tightly held between the clutches. The 
hand does not tire on continued holding, because the 
pressure is taken in a straight line on the bones of the 
thumb, and hence calls for so slight a muscular adion as 
to be pradically inappreciable. 

The clamp is manufadured by Ermei and Amend. — 
youmal of iki Amtriean Chemical Sociity. 



PROCEEDINGS OF SOCIETIES. 

CHEMICAL SOCIETY. 
Ordinary Muting, Novimbtr 2Ut, 1895. 

Mr. A. G. Vbrnon Harcourt, President, in the Chair. 

Cbrtificatbs were read for the first time in favour of 
Messrs. Joseph Edwin Alger Blyde, Nether House, 
Ranmoor, Sheffield; Arnold Eiloart, 2, Lansdowne Road, 
Bast Croydon; Walter Thomas Grice, 9, Dalhousie 
Square, Calcutta; James William Helps, 3, Tavistock 
Road, Croydon ; Laurence W. Matthieson, 104, Grove 
Road, Bow, E.: Thomas Francis Rutter, The Huisb 
School, Taunton ; Arthur Philip Salt, Sunnyside, Pinner 
Road, Harrow; Amrita Lai Sircar, 51, Sankaritola, 
Calcutta; Benjamin Bernard Turner, a8, Lady Somerset 
Road, N.W. ; and of Cass L. Kennicott, 4050, Ellis Arc, 
Chicago, 111., U.S.A., approved by the Council under By- 
laws I, 3. 

The Prbsidbnt announced that a letter of thanks had 
been received from the French Academy, for the Address 
presented by the Society on the occasion of the centenary 
of the Academy, on Odober 25th. 

Of the following papers those marked * were read : — 

*I35. " The Influence of Temperature on Refractive 
Power, and on the Refraction Equivalents of Acetyl- 
acetone and of OrthO' and Para»toluidine,** By W. H. 
Pbrxin, Ph.D., F.R.S. 

The author points out that whilst he has proved that 
the refradion equivalent of certain compounds is subjed 
to variation at different temperatures, and Briihl has ob- 
served the same fad, his numbers, and those Obtained bv 
Briihl, are not in agreement. In the case of acetyf- 
acetone, the toluidines, and other compounds, it is ob- 
served that the two sets of determinations agree closely 
for ordinary atmospheric temperatures, but at higher tem- 
peratures Briihrs numbers show an increase, whilst the 
author obtains smaller numbers at higher temperatures. 
The author has satisfied himself that the apparatus used 
by him {Trans., 1892, 288) consisting of a hollow prism 
heated in an air-bath, furnishes uniform results, and bv 
making observations with different specimens of material, 
he has proved that the differences between his numbers 
and Briihrs cannot be ascribed to impuritv. Since the 
results for higher temperatures obtained by Nasini and 
Bemheimer, and by Kettler, using more or less indepen- 
dent methods, agree with the author's, he concludes that 
there must be some hitherto undiscovered error in the 
use of BrCihrs refradometer at any temperature much 
above that of the atmosphere. 



^136. " The Evolution of Carbon Monoxide by Alkatim 
Pyrogallol Solution during Absorption of Oxygen.** By 
Frank Clowbs, D.Sc. 

It has long been known that under certain conditions 
carbon monoxide is evolved during the absorption of oxygen 
by alkaline pyrogallol. When a solution, 100 c.c. of which 
contains xo grms. of pyrogallol and 24 grms. of potassium 
hydroxide, is used for the absorption of oxygen, it evolves 
no carbon monoxide until the percentage of oxygen in 
the gaseous mixture exceeds 28. The carbon monoxide 
evolved, however, increases in amount as the percentage 
of oxygen rises above that limit, until the carbon monoxide 
finally reaches about 6 per cent of the volume of oxygen 
absorbed. 

The process of estimation of oxygen is rendered per- 
fedly accurate if the carbon monoxide which has been 
produced during the absorption is removed by means of 
cuprous chloride solution before the reading is taken. 

Experiments with pyrogallol solution containing larger 
proportions of potassium hydroxide than that given above 
proved that the evolution of carbon monoxide may be en- 
tirely prevented under all conditions if the potassium 
hydroxide is present in sufficiently large proportion. 

A solution, 100 C.C. ofwhich contains 10 grms. of pyro- 
gallol, and 120 grms. of potassium hydrate, proved per- 
fedly satis fadory in this resped ; the weight of pyro- 
gallol may be reduced to 5 grms. in this solution. 

A solution containing 18 per cent of quinol (hydro- 
quinone) and 24 per cent of potassium hydroxide absorbed 
oxygen slowly, but the absorption was complete, and no 
carbon monoxide was evolved. 

It is therefore evident that serious error may arise la 
estimating the proportion of oxygen present in a mixture 
containing only small proportions of other gases, unless 
the absorbent pyrogallol solution is prepared of suitable 
strength, or unless the absorption of oxygen is followed 
by the treatment of the residual gas with cuprous chloride 
solution. 

•137. **The Composition of the Limiting Explosive 
Mixtures of various Combustible Oases with Air.** By 
Frank Clowes, D.Sc. 

A series of experiments were made with mixtures in 
varying proportions of each combustible gas with air. A 
flame was brought into contad with each mixture, some- 
times above and sometimes below, and it was noted 
whether the mixture burnt back independently of the ex- 
ternal air. For each combustible gas there was thus ob- 
tained a lower percentage below which the mixture would 
not burn independently, and a higher percentage, above 
which the gas burnt independently only when it was sup- 
plied with mote air. 

The limiting percentages were as follows :~For me- 
thane, 5 and 13 ; for hydrogen, 5 and 72 ; for carbon 
monoxide, 13 and 75 ; for ethylene, 4 and 22 ; for water- 
gas, 9 and 55 ; for coal-gas, 5 and 28. 

It was also proved that many mixtures which were out- 
side but close to the above limits, and which could not be 
fired from above could be fired from below. 

Hence it is inferred : — 

z. That the limiting explosive mixtures for difieient 
combustible gases vary widely. 

2. That methane shows the narrowest limits, hydrogen 

the widest limits. 

3. That the risk of a mixture being fired explosively in- 

creases with the different gases in the following 
order: — Methane, ethylene, coal-gas, water-gas, 
carbon monoxide, hydrogen. 

4. That the risk of explosion is greater when the mix- 

ture is kindled from below than when it is kindled 
from above. 

Discussion. 
Mr. Bennett H. Brough considered that it would have 
been a valuable addition to Professor Clowes*s investiga- 
tions if the adion of other methods of firing had been 
tried. For it had to be remembered that coUiery ezplo- 



CsnacAL NBWt,! 



Red Spectrum of Argon. 



289 



■ioBB were sometimes due to inflammatioD by sparks such 
as were produced by picks. Some interesting experi- 
ments bad recently been made in the Moravian Ostrau 
coalfield in Austria with an apparatus for testing the 
linbility of gaseous mixtures to inflammation in that way. 
A wheel was mounted on a vertical axis inside a casing, 
which was hermetically sealed and provided with a large 
removable cover. Definite proportions of gas were intro- 
doced and mixed with the air by revolving the wheel. An 
iron bar sliding through the casing was brought against 
the revolving wheel, and in case of an explosion the 
coiver, which was secured by a chain, was blown off wi th- 
orn farther damage. 

*X38. **Not0 OH th$ Estimation of Butyric Acid.*' By 
W. H. Wilcox, B.Sc. 

In the estimation of butyric acid in the presence of 
acetic and formic adds, the acids were neutralised by a 
known excess of calcium carbonate. Hydrochloric acid 
was added in sufficient amount to neutralise the free cal- 
cium carbonate and to liberate the butyric acid from the 
calcium salt. The solution was distilled, and when the 
greater part had passed over, steam was passed through 
tlie liquid as long as the distillate continued acid. The 
distillate, which contained the butyric acid, was boiled 
with pure barium carbonate, the solution filtered, and 
•vaporated to dryness. 

It was found that when dried at 100^ C, the salt did 
did not attain a constant weight even after it had been 
heated for several weeks, diminutions of about a m.grms. 
(with I to 2 grms. of salt) occurring after heat had been 
applied for three hours. This loss of weight did not 
occur at and below 8o^ 

Some barium butyrate was prepared, and was found to 
lose weight in a similar manner. At 90—100^ C. losses of 
about a m.grms. occurred with three hours heating of 1*5 
grms. of salt, and even at 85^ C. loss of weight occurred 
on continued heating. When the salt was kept at 80® C, 
however, it speedily arrived at a constant weight, which 
was not altered by continued heating. 

These results show that in the estimation of mixtures 
of the volatile fatty acids, when butyric acid is present, 
the fradion of salts containing the butyrate must be dried 
at a temperature not exceeding 80° C. ; if this tempera- 
tore is exceeded, loss of weight occurs owing to the de- 
composition of the butyrate. 

Z39. ** Some Derivative of Anthraquinonc,** By 
Edward Schuncx, Ph.D., F.R.S., and Lbon March- 
LBWSXI, Ph.D. 

The authors have prepared the three hitherto unknown 
methyl purpuroxanthins. One of them was obtained by 
condensation of o-toluic acid with m- hydroxy benzoic 
acid. It crystallises in orange-coloured needles (m. p. 
246^). Its diacetyl derivative is nearly colourless (m. p. 

The other two methylpurpuroxanthins were obtained 
by condensation of m-toluic acid and m-hydroxybenzoic 
acid. The mixture of methylpurpuroxanthins produced, 
3rielded two distind compounds by fradional crystallisa- 
tion from a mixture of alcohol and benzene. The con- 
stitution of these compounds was determined by studying 
the produ^ of their oxidation. The more soluble one 
gave, on treatment with nitric acid, trimellitic acid, while 
the other one gave, on similar treatment, hemimellitic 
add. 

The authors point out that the constitutional formulas 
proposed 1^ them (Trans., 1894, 186) for the ethers of 
alizarin are supported by the work of Lagodzinski {Bit., 
1895, Z427), who obtained a monomethyl ether of alizarin 
by the condensation of hemipinic acid with benzoic acid. 

The authors give a more precise account of the ethers 
of anthraquinoneoxime, mentioned by them in a prelim- 
inary paper previously published IBcr,, 1894, 2125). The 
methyl ether melts at 247^ the ethyl ether at 97*, and the 
bMueyl ether at 8a^« 



X40. *' Efflortscencc of DoubU Ferrous Aluminium Suh 
phati on Bncks exposed to Sulphur Dioxide.** By David 
Patbrson. 

The author has analysed the efflorescence which ap- 
pears on bricks composing chambers in which wool is 
bleached with sulphur dioxide. Four analyses were made, 
and the results agree well with the percentages required 
by the formula Ala(S04)3,FeS04,a4H20. The salt forms 
white fibrous crystalline masses resembling asbestos in 
appearance. It is evidently identical with the salt often 
found in volcanic regions, and the author's analyses 
agree well with those made by Forchammer of a specimen 
obtained from Iceland. 

Collective Index of the Transactions, Abstracts, and 

Proceedings of the Chemical Society, 

Volume II., 1873 to 1882. Volume III., 1883 to 1892. 

The Council, having determined to publish a ColleAive 
Index of their publications from 1873 to 1892 inclusive, 
will issue copies to Fellows who may notify their wish to 
receive them. Both volumes will be sent to those who 
were Fellows of the Society before the end of 1882. 
Volume III. will be sent to Fellows who have joined the 
Society between ist January, 1883, aQ<1 3^8^ December, 
Z892. Fellows who are ineligible to receive copies gratis, 
and those who may have negleded to apply for them 
within the prescribed period, may obtain them by pur* 
chase at a price to be hereafter fixed. Fellows who desire 
the Index should notiff their wish by letter, enclosing i/* 
for cost of distribution, &c., to the Assistant- Secretary, 
Mr. Robert Steele, Chemical Society, Burlington House, 
W., before 3xst December, 1895. ^^^ Fellows resident 
abroad, who should remit 2/-, which may be paid with 
their annual contribution, the time will be extended to 
March zst, 1896. 

A few copies of Vol. I. (1841—72) can still be obtained, 
price 3/- post free. 

Research Fund, 
A meeting of the Research Fund Committee will be 
held in December. 



IMPERIAL ACADEMY OF SCIENCES OF 

VIENNA. 

Session of the Mathematical and Natural Science Section, 
of October 24th, 1895. 

•• On the Red Spectrum of Argon.** By Dr. J. M. Edbr 
and Dr. E. Valbnta. 

By the kindness of Lord Rayleigh we obtained a speci- 
men of argon gas which had been carefully introduced 
into vacuum tubes by Herr Goetze, of Leipzig. The 
pressure in the tubes which we used in our experiments 
was from z to 3 m.m. For the speAroscopic analysis of 
the argon we used a concave grating having a radius of 
curvature of | metre, employing the photographic method. 
We examined the red and the blue speArum obtained by 
working according to the dire^ions of Mr. Crooke's, with 
weak sparks without Ley den jars, or with sparks from 
the jars. 

For the red spedlrum of argon we obtained the numbers 
quoted below. The lines marked with asterisks in the 
author's tables are present also in the blue spedrum of argon. 
The other lines are peculiar to the red argon spedrum. 
The especially charaderistic lines of the red argon spedrum 
are:— X 462856, 4596*22, 4522'49. 4510-85, 4300-18, 
4272*27, 425942, 4251*25; especially the group 420076, 
4x98*42, 4198*07, 4x64*36, 4158*63 *, and further, 4044*56, 
3949*13, 3834*83. Further measurements will appear in 
the Transactions of the Imptrtal Academy. It must also 
be remarked that the red argon spedrum is well resolved 

when the double line {Ij^.lf appears clearly separated. 



2go 



Simple Methods for Detecting Pood Adulteration. 



If the blue and the fed argon spedrum belong to two ele- 
ments, which is by no means improbable, the above lines- 
woald be the main charaderistic lines of one of them. 



NOTICES OF BOOKS. 



A Handbook of Industrial Organic Chemistry : adapted 
for the Use of Manufadurers, Chemists, and all inte- 
rested in the Application of Organic Materials in the 
Industrial Arts. By Samuel P. Sadtlbr, Ph.D., 
F.C.S., Professor of Chemistry in the Philadelphia 
College of Pharmacy, and in the Franklin Institute of 
the State of Pennsylvania, &c. Second and Revised 
Edition. 8vo., pp. 537. Philadelphia : J. B. Lippincott 
Company. London: 10, Henrietta Street, Covent 
Garden. 1895. 
PaoF. Saotlbr admits that there is, on the one hand, no 
lack of technological manuals for separate chemical in- 
dustries, such, i,g,, as tanning and dyeing ; and, on the 
other hand, of encyclopasdic works embracing the entire 
compass of the chemical arts, but that there is a scarcity of 
works which attempt to give, within the compass of a single 
volume, a general view of the various industries based 
Qpon the applications of chemistry to the arts." The 
reason of this rarity is not difficult to find. The chemical 
industries are now so numerous and so elaborate that to 
give in a single volume anything beyond a mere sketch of 
each, of comparatively little praAical value, is indeed an 
arduous task. To escape this difficulty the author confines 
himself in the volume before us to the organic arts, and 
promises to give an account of the inorganic chemical 
industries in a future volume. This expedient certainly 
reduces the bulk of the matter to be dealt with, but it 
encounters the difficulty that there is no hard and fast 
boundary line between the organic and inorganic chemical 
arts. 

If we turn to the subjeds discussed in this volume—' 
such as tanning, soap-making, dyeing, bleaching, and 
tissue-printing — we find that they are at once organic 
and inorganic. The same must be said of the manufac- 
ture of chemical manures, of painters* colours, and 
writing inks, which are not mentioned in the work before 
at, aod each of which would likewise overstride the 
boundary line. Again, when the companion volume ap- 
pears the work will no longer give a view of the chemical 
Industries within the bounds of a sinele volume. 

If we iriight suggest, a principle of division preferable 
to that of ** organic and inorganic*' might be found, 
though it would not be easy to find scientific names for the 
two respedive groups of industries. Let us suppose, by 
way of explanation, that on visiting some strange town 
we were to enquire what chemical works there were in 
the distria. We should then feel startled if we were told 
of a number of dairies, bake-houses, breweries, and sugar- 
works. Yet the processes carried on in these establish- 
ments are unquestionably chemical. Still we feel, however 
difficult it may be to put the distindion in words, that 
they do not belong in the same category as bleach-works, 
soap-works, or tanneries. 

Passing from questions of arrangement to the subjed- 
matter itself, we must congratulate Dr. Sadtler on the 
rare felicity with which he has condensed into so small a 
space so large an amount of valuable matter. Oversights 
and errors are indeed rare. We note merely a passage 
which seems to convey the impression that indigo is al- 
ways applied to textile goods by means of the cold vat, 
whilst in fad the warm vats arc chiefly used in woollen- 
dyeing. ... .. , 

A most valuable feature of this book is the biographical 
department subjoined to each sedion. The student is 
thus furnished with a master-key which opens to him all 
the details of technical chemisuy. 



f CatMicAL Ntvt, 

1 Dec 13, 1605. 

Hints on th4 Teaching of Elementary Chemistry in Schools 
and Science Classes. By W. A. Tilden, D.Sc, F.R.S. 
Crown 8vo., pp. 76. London and New York : Long- 
mans, Green, and Co. 1895. 
Manuals of elementary chemistry are far from rare,— > 
too plentiful, indeed, as we are sometimes tempted to 
think. But the little work before us is exceptional in its 
charader. It is addressed not to students, but to teachers, 
and thoroughly good lessons does it convey. Pity, 
though, we must add with bated breath, that any teacher 
of chemistry, or of any science, should need such hints. 

In the first sentence of the Preface Dr. Tilden rejoices 
over the issue of a new " Syllabus.** It may be a very 
important advance in the teaching •! chemistry, as giving 
more scope to the discretion of the teacher. But there 
would be still greater room for congratulation if the new 
** Syllabus '* were the last of the race I It is appropriately 
urged that the teacher should devote some part of bis 
time to extending and consolidating his own knowledge. 
Should he need any such reminder ? We find a denun- 
ciation of the " crammer,** but due refledion will tell us 
that this unlovely being is a bye-prodnd of exam- 
inationism. 

We are inclined to agree with Prof. Tilden when he 
expresses the opinion that the study of chemistry, when 
rightly taught, is the best means of cultivating the 
faculty of observation. The general incapacity of dis- 
tinguishing objeds unless they differ markedly in sise or 
colour is duly regretted. This incapacity is, we fear, 
most striking in those who have '* enjoyed *' a classical 
education. 

The author points out that chemistry cannot be learnt 
by reading alone. The eye and the hand must first be 
trained. One of the dangers of working frona text-books 
is that ** the student imbibes the idea that the subjed is 
complete, rounded off, and finished, and that he sees 00 
room for further inquiry.** 

It will not, we hope, be deemed irrelevant if we poiot 
out the fatal blow which the examinational system has 
just received. In the Chinese Empire, for ages, all 
statesmen, generals, judges, and magistrates have been 
seleded by competitive examination. The outcome has 
been the collapse which the world has just witnessed. 
Intelledually and morally the examinee has been weighed 
in the balance and found utterly wanting. 



SimpU Methods for Detecting Food Adulteration, By 
John A. Bower. With 36 Illustrations. Published 
under the Diredion of the General Literature and 
Education Committee. Small post 8vo., pp. xx8. 
London : Society for Promoting Christian Knowledge. 
X895. 
Time was when the publications of the Society for Pro- 
moting Christian Knowledge were spoken of with scanty 
resped, but the number of valuable works by writers of 
acknowledged merit which have appeared with the 
imprimatur of the Society have done away ¥fith such an 
unjustifiable feeling. Mr. Bower*s work is not intended 
as a guide for the student or a work of reference for the 
professional analyst, but it is calculated to guard the 
general public against frauds which affed their pocket, if 
not their health. 

The author concludes that '* adulteration is decidedly 
on the decrease,'* and again, that '* our food is not adul* 
terated to an alarming extent.** Yet he qualifies these 
disclaimers by the admission that, as recently as the year 
1891, ** about 12 per c^nt of all the food sold in this 
country was adulterated,** that coffee is sometimes sophis- 
ticated ** to the amount of 75 per cent,'* that milk may 
contain from 20 to 30 per cent of added water. Now 
these fads show, we submit, that adulteration is still 
carried on to an ** alarming extent,*' and that the apathy 
of the public — the persons thus defrauded — is in itsell 
almost criminal. 



^fs^} Plac^ of Helium in the Classification of Elementary Substances. 291 



Dm. 



Mr. Bower qaotes several eUuset of the *' Sale of Food 
and Drugs Ad,V which has many deficieDciei. Thus, in 
the case of coffee, to sell mixtures of coffee and chicory 
not contpicuously labelled as such is undoubtedly punish- 
able ; but if an enterprising tradesman wishes to sell 
cbkory at the price of coffee, and of course to people 
who prefer coffee and do not want chicory, he needs 
merely sell his mixture as ** French coffee,** or ** Coffee as 
in France,** and he escapes the provisions of the Ad I 
It would be easy to put a stop to this disgraceful fraud. 
Until lately it was prsdicable to avoid this fraud by 
always buying coffee unground ; but criminal ingenuity 
now manufaAures spurious coffee-beans, as well as spu- 
rious peppercorns, nntme^^s, and, we believe, gall-nuts. 
Such devices require a punishment heavier than fines. It 
should be enaded that any person designing, construding, 
vending, offering for sale, or using any machine, mould, 
stamp, or die for making up any powder, paste, or pulp 
into the shape of any berry, nut, or seed used in food or 
medicine, or selling any produds thus moulded, shall on 
coovidion be sentenced to imprisonment for not less than 
six OMMiths. 

A fraud in the sugar- trade has escaped the author's 
notice. Continental growers of beet-sugars colour some 
of their unrefined produd with yellow coal-tar dyes, and 
export the precious mess to England under the name of 
Demerara sugar 1 Thus they kill two birds with one 
atone. They sell their rank tasting produce for more than 
\l is fairly worth, and they damage the reputation of 

Knuine Demerara sugars. Even the bees and the wasps 
ow the difference between beet- and cane sugars, and 
rejed the former if the latter is accessible. 

We believe that this work, addressed as it is to the 
general public, will aid in the necessary task of creating 
a healthy hostility to sophistication and sophisticators. 

An Exgrcise Book of BUmtntary Practical Physics, By 
Richard A. Gregory, F.R.A.S. (Oxford University 
Extension Ledurer). Pp. 172. London and New 
York: Macmillan and Co. 1895. 
Tbis book, we are told on the title-page, is intended for 
** organised Science schools under the Department of 
Scteoce and Art, evening continuation-schools and ele- 
mentary day-schools." We further learn that it has been 
** arranged according to the Head-masters* Association 
Syllabus of Pradical Physics.** The table of contents 
reproduces the Head-masters* Association Syllabus, with 
a few chaogea and additions. 

The reader will perhaps find the term *' physics ** here 
used in a sense which he scarcely expeded. 

Light, eledridty, and magnetism are not touched upon 
at all, and heat very slightly. The main subjed of the 
work is mechanics, with meteorology. What the book 
undertakes to teach, however, is well taught, and thoae 
who have made use of it, whether teachers or students, 
will not find that they have anything to unteach or un- 
learn. 



Franklin Instituti : Announctmcnt and Programme of 
Ltcimns. 1895—1896. No. 15, South Seventh Street, 
Philadelphia. 
Tbb organisation of this Society is rather complex. It 
haa a board of trustees ; a staff of officers and managers ; 
a board of management ; two curators ; four professors 
for the respedive departments of mechanics, physics, 
chemistry, and economic geology ; and a number of com- 
mittees. There are five classes of members, via., contri- 
buting members, stockholders, life members, permanent 
members, and non-resident members. 

Among the ledures in the ensuing session the following 
•re, from our point of view, the most interesting:^ 
*« Metallurgical and other Features of Japanese Swords,*' 
by Mr. B. S. Lyman ; ** Recent Improvements in the 
Chemical Treatment of Fibres and Fabrics,*' by L. J. 
Mates ; ** Modem Theories of Fermentation/* by Dr. P. 



Wystt; *' Eledro-metallurgy of Aluminium,** by Dr. J. 
W.Richards; ** Some Recent Work in Molecular Phy. 
sics,'* by Prof. R. A. Fessenden; "What constitutes a 
Good and Safe Drinking Water?** by T. M. DrowOi 
M.D., LL.D., of Lehigh University. 

Craft Instruction : Photography and Process, 
This pamphlet, which is issued at the Polytechnic Insti- 
tution, W., bears no suthor's name. It consists of an 
elaborate prospedus of the photographic department of 
the Polytechnic Institution, which is now in its fourteenth 
session. There are also the advertisements of a number 
of manufadurers of, and dealers in, cameras, lenses for 
photogrsphy, and accessory appliances. 



CORRESPONDENCE. 

ON THE 

PLACE OF HELIUM IN THE CLASSIFICATION 
OF ELEMENTARY SUBSTANCES. 

To the Editor of the Chemical News, 
Sir, — In the report of the recent meeting of the Physical 
Society of November 22nd in the Chemical News (vol. 
Ixxii., p. 266), in which the investigstions of Profs. Runge 
and Paschen on the spedrum of the new gases from 
cliveite are referred to, I observe that Dr. Gladstone 
places these gases between hydrogen and lithium, in order 
that they may come into a classification based on a sup- 
posed periodicity of chemical properties when the ele- 
ments are arranged in seriatim order of their atomic 
weights. I have shown elsewhere why the new gsses 
cannot be allocated to the places assigned to them by Dr. 
Gladstone, end have to express my surprise thst this 
chemist should, by loose arithmetic and still looser 
assertions, endeavour to controvert the reasons I have 
given for placing the new gases at the head of the second 
and third series of my table of elementary substances. 
The mis-statements to which I take exception as hindering 
the progress of chemical science are — 
(x). That the successive differences between the 
atomic weights of adjacent members of the metals 
in the first group in MendeleeflPs table showed that 
these differences increased as we go downward. 
And (2). '* That if the new gases have atomic weights of, 
say, 2 and 4, we should have for these differences a, 
2, 3. 16, x6, 26, ftc, instead of 6, x6, 16, ftc.« as at 
present.** 
Now the incorredness of these alleged increasing dif« 
ferences in the atomic weights will be at once apparent 
from a simple inspedion of the first group in Mendeleeff*s 
table, in which I have included Dr. Gladstone's numbers 
for the new gases. 

DiC 
H - I 



HI, - 
Hla - 4 
Li « 7 



— 2 



Na 



- 3 

- x6 



23 



K - 39 
Cu «- 63 



- x6 



- ^4 



Rb 
Ag 
Cs - X33 



85 
to8 



- 22 



- 23 

- 25 



ngs 



Chemical Notices from Foreign Sources. 



iCHBMICAL MBWft, 

' ft Dec 13. 189s 



It will, moreover, be evident that, even if the successive 
differences between the atomic weights in the first groap 
increased as Dr. Gladstone alleges, the numerical relation 
would afford no ground for placing the new gases above 
lithium, as they might for the same reason be placed 
above the typical members of any other group in Men- 
deleefi^s table. 

In my paper on '* Some New Relations of the Atomic 
Weights" published in the Chemical Nbws (vol.xxxviii., 
p. 66, ftc), I have shown that in the first group or series 
H» all the atomic weights after Na have a constant differ- 
ence of 23 ; and in the second series Han a common differ- 
ence, after Mg, of 24. As these series are of considerable 
interest at the present time, I will, by your permission, 
reproduce the part of my table containing them, with the 
addition of the accepted atomic weights for the purpose of 
comparison. 



-f-Hii- 



+ H2W- 



a. 


Li - 7 
.. .. 7» 




Gl « 8 
.. .. 9a 




3. 


Na» 23 
.. .. n 


F - 19 
.. .. 19 


Mg- 24 
.. .. 24 


0-16 

.. .. 16 


4- 


K - 39 
.. .. 39 


CI- 35 
.. .. 355 


Ca a 40 
.. .. 40 


S ■> 32 
.. .. 3a 


5- 


Cu « 62 
.. .. 633 




Zn « 64 
.. .. 65 




6. 


Rb» 85 

.. .. 85 


Brs 81 

.. .. 80 


Sr « 88 
.. .. 87-5 


Se - 80 
.. .. 79 


7. 


Ag -X08 
.. .. 108 




Cd =1x2 
.. .. 112 




8. 


Cs «i3i 
.. .. 13a 


I eZ27 
.. .. U7 


Ba -136 
.. .. 137 


Te -X28 
.. .. xa8 


9. 


M =154 




X sx6o 




10. 


* -177 




X -X84 




zx. 


Hg B200 

.. .. aoo 




Po =208 
.. .. ao7 





* Accepted atomic weights. 

In this table it will also be seen that the negative ele- 
ments of the first and second series after CI and S have 
constant differences of 46 and 48 respedively, or double 
the differences of the atomic weights of the members of 
each adjoining positive series of elements. The common 
difference of x6 of the atomic weights in the table above 
K, CI, Ca, and S are equally interesting and significant. 
I have already, in the paper referred to, direded attention 
to the common difference of 4 between the halogens and 
the alkaline metals in homologous positions, and the 
common difference of 8 between the oxygen series and the 
alkaline-earth metals in similar positions : while the fad 
that the theoretic atomic weights of the members of the 
four series, when taken together, differ by less than half 
of one per cent from the aAual determinations establishes 
the law of the multiple relations and constant differences 
of the atomic weights of these series on a solid and im- 
mutable basis — the heritage of chemical science for all 
time. — I am, &c., 

Henry Wildb. 

December 3. 1893- 



CHEMICAL EDUCATION. 

To thi Editor of iht Chemical News. 
Sir,— Your correspondent '* W. A. D." has certainly 
pointed out one of the causes why chemical research is 
not more abundant in Britain, and why many of our che- 
mical arts are declining. The evil faAor is the exorbitant 
price of alcohol, a reagent constantly required both in 
research and in manufadures as £ar as organic produAs 
are concerned. Methylated spirit did, indeed, to a great 



extent lighten the burdens of the chemist, but, suadmU 
diavolo, this concession has now been stultified by the 
excise ukase demaoding the further addition of mineral 
naphtha. Whether this stipulation has been made in the 
fancied interest of the revenue or of '* temperance " it has 
been decided without any regard to the interests of Science 
or Industry. If it is necessary to render methylated spirit 
absolutely uodrinkable the addition of a mere trace of 
DippePs animal oil, as the German Government allows 
for alcohol to be used in the colour industries, would have 
met the difficulty. 

It is perfe Aly true that a methylated spirit may be obtained 
free from mineral naphtha, by dint of a sufficient unrolling 
of red tape, and with the pleasant condition of rendering our 
laboratories or works open to the visits of the exciseman. 
I'he only marvel is not that the Government took a 
foolish step, but that the interests threatened did not at 
once rise on the defensive and insist on the withdrawal of 
the oppressive regulation.— I am, &c., 

W.S. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



Note.— All degrees of temperature are Centifrade onless otherwiie 
expressed. 

Compta Rendus HMomadaires des Seances, de t^Academk 
des Sciences, Vol. cxxi., No. 2X, November x8, 1895. 

On an Element, probably Novel, existing in the 
Terbias. — Lecoq de Boisbaudran.— I solicit the Academy 
for permission to submit a paper which I have written 
formerly (May 3, x886) on an absorption-band observed 
in certain portions of a fradionation of terbia, and which 
I believe to be charaAeristic of a peculiar element. I had 
hoped to continue the study of this band, but having sue- 
cessively used up my samples of terbia in various experi- 
ments, there remains so little of this earth that further 
fradionations have become impossible. My memorandum 
of x886 is: — My present terbia is an earth of a deep 
reddish brown, the hydrochloric solution of which gives 
only a weak absorption spedrum, entirely composed 0^ 
the bands of dysprosium, and of a band which appears to 
belong to a new element. This is a brief description of 
this band :-> Micrometer, 140*8 ; X, 4877. Observations : 
Apparent medium of a nebulous band, a little more in- 
distind on the left than on the right. Breadth, from 2 to 
2} degrees of the micrometer ; intensity, moderate. The 
band X40*8 does not appear to belong to TatOs, since it 
is seen at least as strongly in earth of a little brightet 
colouration, as in my purest terbia. It does certainly nor 
belong to dysprosium, being more or less strong than the 
band Dy /9 148*3, according to the produds examined. 
Provisionally I shall name the earth producing the band 
X40-8 (X-4877) ZZ, 

Origin of Atmospheric Oxygen.—Dr. T. L. Phipson. 
The author's views on this subjed have already appeared 
in the Chemical News for the years 1893 and 1894. 

Synthesis of Metbyleogeool. Congtitution of 
Eugenol — Ch. Mooreu. — The author causes allyl iodide, 
ICHa — CHsCHa, to read upon veratrol in presence of 
xinc powder. The method admits of generalisation, and 
he intends to apply it to the synthesis 0/ safrol, anethol, 
and estragol. 

Choleaterines ol the Cr3rptogam8.~E. Gerard. — The 
chloresterines existing in the lower plants all belong to 
the group of ergosterine. 

Distribution of Petftase in the Vegeuble Kingdom, 
and on the Preparation of ibis Dtaataae. — G. Beruand 
and A. Mallevre. — Pedase may be considered as occur- 
ring oniversally in green planu. It is eapecia)^ aboa* 



CHmMICAL NBWt,| 

Dec 13, 1895. f 



Chemical Notices from Foreign Sources. 



293 



dant iD the leaves, from which it is extended into the 
other organs. The richness of certain leaves in pedase 
allows us to realise for the first time the proportion of 
this ferment. 

Retting of PUx, and on itt Microbian Agent.— S. 
Winogradsky.— The organism in question is relatively 
large, forming spores in the terminal swellings (tadpole 
abape). Its joints are from 10 fito 1$ /i in length by 0*8 fi 
in thickness. The retting of flax may be considered as a 
pedic fermentation in the microbiological sense of the 
word. 



Zeitschrtft fur Anorganische Chemie^ 
Vol. viii., Parts 4 and 5. 

The late Professor Q. Kriiss. — A faithful record of 
the life and adivity of the late founder and editor of the 
Z^itsehri/t fur Anorganische ChemU, with a bibliography 
of his memoirs and publications, truly wonderful con- 
sidering his early death. 

Revision of the Atomic Weight of Strontium. — 
Th. W. Richards.— Already inserted. 

Determination of Carbon in Iron.— P. Foerster.— 
Among the procedures which give trustworthy values for 
the determination of carbon in iron, the copper- 
ammonium chloride can be executed with the simplest 
appliances at hand in every laboratory, and does not make 
each demands on the experience ot the analyst as does, 
g,g,^ the chlorine process. Sometimes its general appli- 
cability is interfered with by the fad that some sorts of 
wrought irons, especially tungsten-steels if in contad 
with a quite neutral solution of copper-ammonium 
chloride, give a violent escape of gaseous hydrocarbons. 
In snch cases the author, instead of a solution of copper- 
ammonium chloride, uses a solution of copper-ammonium 
oxalate. This is obtained by mixing a 10 per cent solu- 
tion of copper sulphate with a solution of ammonium 
oxalate saturated in heat until the initial precipitate is 
re-dissolved. Of this solution, 250 c.c. are poured upon 
a to 3 grms. of the tungsten- steel to be analysed, and 
heated together in the water-bath at 80* for five hours. 
Copper separates out, and the liquid takes a green colour. 
It is decanted away from the residue, the copper is dis- 
solved away with a solution of copper-ammonium 
chloride, when the residual carbonaceous substance, after 
filtration and drying, is burnt in a current of oxygen. 

Atomic Weights of Nickel and Cobalt.— Clemens 
Winkler. — Already inserted. 

Acidimetric Determination of Molybdic Acid. — 
Karl Seubert and W. Pollard. — In the summer of 1890, 
by occasion of the analysis of a hydrated molybdic acid 
which had crystallised out of a molybdenum solution, we 
made the experiment of determining the proportion of 
free acid in the precipitate by supersaturation with soda- 
lye and titrating back with hydrochloric acid, using 
phenolphthalein as indicator. The results were satisfac- 
tory. Various indicators were used, but only phenol- 
phthalein and litmus proved satisfadory. The lye must 
be carefully prepared, and should be preserved from car- 
bonic acid. 

Qnantitative Separation of Metals by Hydrogen 
Peroxide in Alkaline Solutions.— P. Jannasch and A. 
Rdttgen. 

Action of Heat upon Carbon Sulphide.— Henryk 
Ardowski.— By the adion of beat upon the vapour of 
carbon sulphide, the author obtains the substance which 
occasions the unpleasant odour of carbon disulphide. It 
is probabiy the same as Bela v. Langyel's carbon sesqui- 
Bulphide. 

New Nitroso-compounds of Iron.— K. A. Hofmann 
and O. P. Wiede. — The authors have succeeded in ob- 
taining well-charaderised salts of an acid of the formula 
Pe(NO)2SSOaOH« 



Cause of Osmotic Pressure and of lonisation 
(Eledlrolytic Dissociation).— J. Traube.— A continua- 
tion of a very extensive memoir, not suitable for abstrac* 
tion. 

Determinations of the Molecular Weights of 
Solids, Liquids, and Solutions.— J. Traube.~Not 
capable of useful abridgment. 

AAion of Dry Hydrogen Chloride upon Serpen- 
tine.— R. Brauns.— This paper is chiefly a critique of the 
researches of Clarke and Schneider. It is concluded that 
the hydrochloric gas employed by those chemists was 
mixed with traces of water, and hence could not be re- 
garded as sufficiently dry. It was rendered capable of re- 
adion by the presence of watery vapour, and has thus 
occasioned the decomposition of the magnesium silicate. 
Water was formed by the decomposition of these sili- 
cates, and promoted further decomposition. It cannot 
be concluded from the occurrence of the readion in 
hydrogenous minerals in what manner their hydrogen is 
combined. The number of the Mg— OH groups cannot 
be inferred from the quantity of the chlorides formed. 
Hence the experiments of Clarke and Schneider— in as 
far as they refer to the adion of hydrogen chloride upon 
silicates— are not adapted to yield a decision on the con- 
stitution of the silicates examined. 

Simple Method of General Applicability for the 
Determination of Water in Silicates.— P. Jannasch 
and P. Weingarten, — This paper requires the accom- 
panying figure. 

The Chemical Composition and Constitution of 
Vesuvian.- P. Jannasch and P. Weingarten.— A tabular 
view of the analytical composition of vesuvian from 
various localities, distinguishing the specimens containing 
fluorine and those from that halogen. 

Opening Up Silicates by the use of Pure Lead 
Carbonate.— P. Jannasch. 

Crystalline Copper Perrocyanides.— J. Messar.— A 
full account of the formation, composition, and properties 
of sodium cuproferrocyanide, sodium cuprocyanide, potas- 
sium cuproferrocyanide, ammonium cuproferrocyanide, 
ammonium cupriferricyanide, magnesium cuproferro- 
cyanide, magnesium cupriferrocyanide, calcium cupriferro- 
cyanide, strontium cupriferrocyanide, barium cupriferro* 
cyanide, and ferrocyancuprammonium. 

J^evue Uniuersille des Mines H de la Mdallurgie. 
Series 3, Vol. xxxi., No. 3. 

This issue contains no chemical matter. 



MISCELLANEOUS. 

Salters' Company's Research Pellowship. — The 
Executive Committee of the City and Guilds of London 
Institute are inviting applications for the appointment to 
the Salters* Company's Research Pellowship for the en- 
suing year. The Fellowship was founded by the Salters* 
Company for the encouragement of higher research in 
chemistry in its relation to manufadures, and particulars 
of the scheme under which the award is made may be 
had on application to the Honorary Secretary, at the 
Head Office of the Institute, Gresham College, Basingh all 
Street, B.C. The results of the researches by Dr. Martin 
O. Forster, the Salters' Research Fellow for the current 
year, at the Institute's Central Technical College, were 
communicated to the Chemical Society at its last meeting. 

Mercury-thymolo-acetate.— E. Merck.— The Che- 
mical Nbws not being a medical organ, we cannot give 
instrudion for the use of any medicine, especially one of 
the ** proprietary " class. The only point we can notice 
is that the bacillus of tuberculosis is very similar to that 
of syphilis. 



294 



Meetings for the Week. 



knvicAL Mbwi, 



HEETIICGS FOR^THE WEEK. 

tictnAW, tftku— Society of Aru, 8. *' Mgchaoiail BMd C«rrift«M.'* 
br H. Wortor Beaomoot, If . Inat.C.E. (C«iitor 
LcAvrttt). 

iTovcoAr, iTtk.— iMtitoto of ChriJ BagiMOfS, t. 
— Potbo'oficAl, 8 30, 



FlMtOfrapbic, 8. 
Socioir Of Af 



\ Arts, 4.50. ** Januioi in tho Past and 
Pnmm,** br Fraak CnndalJ. 
WBOSBsnar, i8cb,- Society off Arts, 8. ** Machines lor Oomposinc 
Letter-prcas Printioc Sorfaces,'* by John 
Sootbwarda 
— ^ British Astrooooiical, 5. 

— » If cteorolocical, 7.90. 

— Geolofficsl, 8. 

^-^ Micfoscoptcsf, 8. 

Tmvuoav, I9th«— Cbenical, 8. ** Liqacfsaioo of Air '* and ** Pro- 
Mrtieft of Liquid Air," by Prof. Dewar. F.R.S. 
Uiscassioo 00 ** The Constitution of Terpeoes 
and t'amphor/* *' Derivatives of Dimethyl- 
sailine/' by If iss Evans, B.Sc 
FsfDAT, toih.-^9tk»u Club, 8. 



TO CORRESPONDENTS. 

C. B. B.— It is doobtfnl whether the proponnder of the question 
whether P should rank a'oof with CI, Br, and I could give a atriaiy 
■deatiftc answer. He asks why is it not ** usually included in that 
gronp ?** He does not say *' iutnrallv*or " legiumately." Fluorine 
was dll verjr lately an element of unknown properties, and hence it 
WM commonly excluded from the group of the halogens. Its chief 
I is (mat its oside has not yet been obtained. 



JUST PUBLISHED. 
446 Pagsi and X04 lUuitratiom, Price 12' 6^* 

A TREATISE ON THE MANUFACTURE 

SOAP and'candles, 

LUBRICANTS, AND GLYCERIN. 

B7 WH. LANT GARPENTER, B.So. 

Second Edition. Revised and Enlarged by HENRY LEASK* 

CONTENTS. 

Historical Epitome and References. Theoretical Principles. 

Raw Materials : Their Sources ani Preparation. 

Raw Materials : Refining, Clarifying, and Bleaching. 

Raw Materials : Their Proximate Analysis. 

Caustic Alkali and other Mineral Salts. 

Mannia^ure oi Household Soapa 1 The Process of Saponification. 

Treatment of Soap after its Removal from the Soap Copper: Cooling, 
Cuttin|(, Drying, Moulding. 

Soap;— Filling and Sophisticating. 

Special Soaps : Household. Laundry, Ploatinff, Disinfedtant, Hard- 
water, Sand, Cold'Water, Powders, Manuf«Aurers', Toilet, 
Transparent, Fancy, Solidified, Glyceriu, &c. 

Theory of the AAion 04 Soap— Its Vahiation and Aaalysis— Distri- 
bution and Position of the Trade. 

Lubricating Oils, Railway and Waggon Grease, &c. 

Csndles— Raw Materials, their Sources and Preliminary Treatment. 

Processes for the Conversion of Neutral Fats into Fatty Adds— The 
MsnufsAure of Commercial Stearin. 

The Msnufadture of Candlen and Night-lights— Their Value as Illu- 
minants. Glycerin. Bibliography. Index. 

E. ft P. N. SPON, 125, Straod, London. 
CITY AND GUILDS OF LONDON INSTITUTE 

FOR THE ADVANCEMENT OF TECHNICAL EDUCATION. 
SALTERS* COMPANY'S RESEARCH FELLOWSHIPS. 

The Court of the Salters' Company having 
placed at the disposal of the City and Guilds oi London Insti- 
tute a Grant of ^150 a Year for founding one or more Fellowships 
for the encouragement of Higher Research in Cheroittrv in its rela- 
tions to ManufaAures, tne Executive Committee of the Institute are 
prepared to receive applications from candidates for appointment. 

Candidates must be British- born subjects. Preference will be 
given to students of the Institute who have completed s full Three 
Years* Course of instruAion in the Chemical Department of the 
Central Technical Lolle^e, hut other candidates dulv qualified in the 
Methods of Chemical Research in its relation to Maoufadturea are 
also eligible, without restriction as to age or place of previous study. 

A Copy of the Scheme, giving particulars of tenure, &c., under 
which the Fellowships will be awarded, may be had 00 application at 
the Head Office of the Institute, Greshsm College, Basinghsll Street, 
London* B.C. 

JOHN WATNEY, Honorary Secretary. 



QHEMICAL WORKS FOR SALE. 

To be Exposed, within the Facahy Hall, St. George's Place, 
Glasgow, on Friday, notb December, 189S. ^ » o'clock Noon,— 

The WORKS of DONALD'S CHLORINE SYNDICATE, ai 
LONGFORD, KILWINNING, AYRSHIRE. 

The Works have been ereAed In a most sohatantial manner for 
the purpose of mannfaAuring Bleaching Powder by the Dooild*! 
Process, Chlorate of Potaah. Chlorate oi Soda, and Sahcake. 

The Buildings and Plant are extcnstre, and inclade CUorioe Plant, 
Drying Towers, Oxidising Towers, Decomposing Plant, Recovery 
Plant, Bleach Chambers, Refrigerator. Lime Mill, Engines, Boilers, 
Steam Pipes. Laboratory, and other Apparatus and Plant. There is 
a railway connc^on, with ample siding accommodation throogboot 
the Works. Any Movable Plant and Stock remaining on the Preau> 
see may he taken by the Purchaser at a Valuation. 

The Ground, extending to s| acres, is held on lease at a moderate 
rent, with right to obtain a perpetual feu, but if desired by the 
Purchaser it may be relinquished at Whitsunday first 

A Break-up Valuation of the Works by an experienceo Andioacer 
amounted to about ^4200, but they will be exposed at the Low Upset 
Price of £4000. 

Folly-deuiled Inventories may be seen in the hands of, and ordeis 
to view may be obtained from, J. M. Taylor and Foolte. Wiitcn, 
180, St. Vincent Street, Glasgow. 



PATENTS, DESIGNS. AND TRADE HARKS ACTS, 
1883 TO 1888. 

TSJOTICE IS HEREBY GIVEN that 

'^^ HaiNsiCH Baum, of No. 28, Forsthausstrasse. Frankfbrt-oo- 
the Main, in the Empire of Germany, haa applied for leave toameed 
the Specification of the Letters Patent No. 19942 of 1893, for ** Im- 

frovements in the ManafaAure of Ortho'halogen- phenol, and in ths 
*rodudion of Pvrocatechine therefrom." 

Particulars of the proposed Amendments were set forth in the 
Illustrated Official Journal (Patents) issued 00 the 4th December, 
1895. 

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Expansion 0/ Argon and oj Helium. 



295 



THE CHEMICAL NEWS. 



Vol. LXXII., No. 1882. 



EXAMINATION OF GASBS FROM CBRTAIN 
MINERAL WATERS.* 

By ALSXANOBR KBLLAS, B.Se., mnd 
WILLUM RAMSAY. Pb.O., FJl.S. 

A SAMPLB of gas of an inflammable nature, sent to Mr. 
Crookes by Mr. C. Lowthian Bell, of Middlesbrough, 
from ** AUbusen's Well," was sent on to us to be tested 
for argon. The usual constituents, nitrogen, hydrocar- 
bons, AC, were removed by the usual absorbents, magne- 
sium, copper oxide, &c., and finally by sparking with 
oxygen over caustic soda. The only noticeable Mature 
was the great difficulty in removing the hydrocarbon, 
which for lonj( resisted the aAion of red-hot copper oxide. 
The circulation had to be continued for two days before 
sibsorption was nearly complete. In one case (Kellas) 
555 c.c. of gas gave a c.c. of residue, and in another 
(Ramsay) 950 c.c. gave 4*5 c.c. This corresponds to 
about 0*4 per cent of indifferent gas. The first portion 
was unfortunately lost, but the spe^um of the second 
portion was carefully compared with that of argon, and 
the lines were all found to be coincident. No new tines 
appeared, nor was any helium yellow visible. 

An incombustible gas from another well at the same 
place was also tested, and was found to contain 0*5 per 
cent of argon (Kellas). 

Some gas from a boihng spring near Reykjavik, Iceland, 
was colleded last autumn (Ramsay), and, on removing 
the combinable constituents, 7*45 c.c. were obtained from 
660 cc of the gas. This is a greater proportion of argon 
than is present in air, being x*X4 per cent. No helium 
could be deteded in the gas, nor were there any lines 
which could not be recognised as belonging to argon. 

It has been thought worth while to place on record 
these experiments, although they show nothing remark- 
able. We have to express our indebtedness to Mr. Noel 
Heaton for help kindly rendered. 



THE EXPANSION OF ARGON AND OF HELIUM 

AS COMPARED WITH THAT OF AIR AND 

HYDROGEN.* 

By J. P. KUENEN, Ph.D., 
Professor of Phjrtica io Uoiveraity College, Dundee, tad 

W. W. RANDALL. Ph.D., 
Leftvrsr io Johns Hopkiai Uoivertity. Bitltimoce, U.SUk. 

Accurate comparisons of temperatures, as read with the 
aid of thermometers filled with different phases, have not 
often been made. The history of the subjed may be said 
to have begun with the classical researches of Regnault 
(** Relations des Experiences," &c., 1847—62). Of recent 
work of this kind, that of Chappuis (Archivti dt Qtnivt 
[3]. vol. XX., pp. 5— 36, 153—179. 248—262; also TraiUi 
9t iiimoins au Sun^u International, vol. vi.) was per- 
formed entirely at temperatures below xoo^ the gases 
employed being hydrogen, nitrogen, and carbon dioxide. 
The experiments ol Grunmach and Fernet {Mitronomischg 
Biitrdge, No. 3) were also condudedat temperatures below 
Ioo^ Crafts (CompUs Rendus, vol. xcv., pp. 836—839), 
has compared the readings of a number of mercury ther. 
mometers with those obtained by Regnault and by himself 
with a hydrogen thermometer. Wiebe and Bdttcher 

* A Paper lead before the Royal Society. 



(Zettschriftjut Instrumintinkundi, vol. x., pp. 16 and 233) 
have determined the boiling-points of a number of liquids 
in terms of the expansion of air. 

In connexion with the work on argon and helium io 
progress at University College, it was suggested by Prof. 
Ramsay that a comparison should be made between 
the readings shown by thermometers containing respe^. 
ively argon, helium, hydrogen, and air. The temperatures 
used were :— the melting-point of ice and the boiling, 
points of water, chlorbenzene, aniline, quinoline, and 
bromnaphthalene respeaively. The gas to be experi- 
mented upon was contained in a bulb about 12 cm. long 
and 2*2 cm. wide, sealed atone end to a fine capillary tube 
about 12 cm. long ; this, in turn, was conneded with a 
piece of thick-walled glass tubing, having an inside 
diameter of about 0-2 cm. The wider tube was fitted 
with a stopcock, for convenience in filling the bulb, and 
at its lower end was cooneded with a stout rubber tubb, 
which led to a movable mercury reservoir. Near the 
point at which the fine capillary tube was sealed to the 
wider tube, a mark was made on the latter : the mercury 
was always brought up to this mark in the experiments, 
and the difference of level in the tube and in the meccury 
reservoir was read off, with the aid of a telescope^ from a 
glass scale graduated in millimetres, which stood direaiy 
behind the apparatus. 

The bulb of the gas thermometer was heated in one of 
Ramsay and Young's vapour-jackets, the mark on the 
stem being just below the cork closing the bottom of the 
jacket : consequently a small portion of the stem was not 
heated to the temperature of the vapour in the jacket. 
The error thus introduced was taken into account. No 
part of the mercury column which compressed the gas io 
the bulb was heated more than a few degrees above the 
temperature of the room, screens being employed to cut 
off radiation : the temperature of the mercury was, how- 
ever, always determined as accurately as circumstances 
would permit, and the readings reduced to o®. In order 
to protea the thermometer bulb from the effeds of radia- 
tion, the jacket was shielded by an outer cylinder of thick 
pasteboard, with an air space between. 

Since the mercury was always brought to the same 
point on the stem of the thermometer bulb, the volume of 
the gas, except for the change produced by the expansion 
of the glass, was in all the experiments the same, while 
the pressure was, of course, different for each temperature 
employed. For convenience the bulb was filled, in the 
case of each gas, at from two-thirds to three-fourths at- 
mospheric pressure : under these circumstances the bulb 
was never subjeaed to an internal pressure greater than 
about li atmos. 

Corr#r/i<ww.— All pressures were reduced to o*. The 
coefficient of expansion of the glass of the bulb was 
carefully determined, and was found to be 0*00002804 : its 
effea was allowed for. The effea of capillarity in de- 
pressing the mercury in the narrow tube was determined 
and taken into account. The volume of that part of the 
stem of the bulb which was not in the ice or vapour, as 
the case might be, was found to be 0*0003 of «he whole, 
and was allowed for in the calculations. The change of 
volume in the bulb due to change of pressure was found 
to be negligible. 

Oaws.— The first gas experimented with was hydrogen. 
This was prepared from pure sine, was washed with 
potassium permanganate solution and then with strong 
sulphuric acid, and was dried with phosphoric anhydride 
before it entered the previously exhausted bulb. The 
thermometer was successively filled and exhausted seve- 
ral times, in order to remove impurities, and was heated 
while vacuous to dislodge any gas clinging to the surfa9e 
of the glass. Finally, the purified hydrogen was allowed 
to enter slowly until the required pressure was obtained. 

Two sets of experiments were made with air. In the 
first set no effort was made to remove carbon dioxide, 
although the air was of course carefully dried. The read- 
ings were made by one of us alone, and, on account of 



296 



Expansion of Argon and of Helium. 



t CaiMtcAL Hwm9t 
1 Dec. so, 1895. 



CorreAed 

Klod of thermometer. prtMare o^. 

I. Hydrogen •• •• — 

9b Air I — 

3. Helium 567*02 

4« Argon 1 5x7*02 

5* Argon II 5^9*54 

6. Air II 5XZ'68 

Air<Wiebe) — 

Temperature (R. and Y.) — 



In iteftm kt khoat 
100*, the temper- 
ature being 
tccuratelv 
' calculated. 

7x2-56 
73774 
775x8 
706*06 

698*79 



CoeAcient 

of expansioo 

at constant 

volume 0—100°. 



0*003665 
0*003668 

0003663 

0*003670 



Temperatures calculated. 



Cblor. 
benzene. 

X3l*6 
X3i*8 

X32*2 

132*15 



1321 



Brom* 



Aniline. 
183*9 
x83*6 
184*1 
184*1 



184-3 
184*4 



Qaio<dine. 

236-35 
Ca34'9J 
2369 

237*8 
237*1 

«35'9 
237*4 



lene. 

281*65 

[«^-3l 

28x*5 



280-4 



the numerous details to be attended to which adaally 
require the attention of two observers to be put beyond 
question, are probably not as accurate as the other series. 
The second series had to be brought to a close after the 
pressures corresponding to o*' and the boiling-points of 
water and quinoline had been determined. In this series 
care was taken to use air free from carbon dioxide. 

The helium used was some of that prepared and purified 
by Professor Ramsay. Its density was 2*13, that of oxy- 
gen being taken as x6. 

The argon employed was prepared from atmospheric 
air by the method of Professor Ramsay. A large gas- 
' bolder was filled with air which had been slowly drawn 
through a long combustion-tube filled with red-hot copper. 
This gas was dried, passed again over the hot copper, and 
then over red-hot magnesium shavings until absorption of 
nitrogen ceased. By these processes a gas was obtained 
consisting of about equal volumes of argon and nitrogen. 
Passage of this gas, backwards and forwards, through 
tubes containing respedively red-hot magnesium, red-hot 
copper oxide (to remove the hydrogen given off by the 
' magnesium on heating), soda lime, and phosphoric anhy- 
dride, failed to remove the nitrogen completely. Finally, 
with the aid of a circulating apparatus (See Rayleigh and 
Ramsay, Phil. Trans,, 1895, A. p. 212), which ensured the 
passage of all the gas over the hot magnesium, a produd 
was obtained whose density was found to be 19*99, oxygen 
being x6. The thermometer was filled with this gas. 

After the pressures exerted by the argon when the bulb 
was surrounded by melting ice and by the vapours of 
water, chlorbenzene, and aniline, successively, had been 
determined, the thermometer was heated in the vapour of 
quinoline, when for some unknown reason, it cracked. A 
new bulb, of the same glass and as nearly as possible of 
the same size, was prepared, cleaned, and filled with 
argon, and a second series of readings made. 

Finally, the argon was replaced by air, and the second 

series of readings for air, referred to above, begun. On 

account of the closing of the laboratory for the summer, 

this series was not carried as far as would have been 

' desirable. 

TtrnpitaiHtis. — ^The temperature of the jacket, when 
filled with steam from water boiling smoothly under 
atmospheric pressure, was taken from Kohlrausch's 
'* Physical Measurements.*' The samples of the boiling 
liquids used were re- distilled, and were found to pass 
over without a rise in temperature of more than a tenth 
of a degree, in three cases ; of a fifth of a degree in the 
fourth case. 

The results of our observations are laid down in the 
table. In three cases (3, 4, and 6) the reading was taken 
at o^ as well as at the boiling-point of water; this 
enabled us to calculate the coefficient of expansion be- 
tween these two points. The result is shown in the 
fourth column. The higher temperatures determined 
with these thermometers have been derived from the ob- 
served pressures by using the coefficients thus measured. 
As the barometric pressures differed, more or less, from 
the normal value, the boiling-points had to be reduced to 
normal pressure, for which operation we made use of the 
differences in Ramsay and Young's well-known tables 



{Chtm. Soc, yourn., vol. xlvii., p. 640 ; vol. !▼., p. 483). 
In calculating the temperatures of air thermometer I., 
where the reading at 0° had been omitted, and of argoo 
thermometer II., where we did not take the reading in 
steam, we used the coefficients found with air thermo- 
meter II. and argon thermometer I., respedively, in the 
first case basing our calculations on the reading in steam. 
With the hydrogen thermometer, where the reading at 0* 
had not been taken, we accepted 0*003663 as the coeffi- 
cient of that gas, and based our calculations of the tem- 
peratures again on the reading in steam. 

Since the readings of the mercury surfaces, with the gas 
thermometer as well as the barometer, were taken on a 
millimetre scale, an occasional mistake in the final 
pressure of o*x or 0*2 m.m. is by no means excluded. 
Uncertainties of that amount do not, however, account 
for the difierences between the results obtained with the 
different thermometers. The readings of air thermo- 
meter I. are, perhaps, somewhat less to be relied upon than 
the others, because they had to be observed, as was stated 
above, by one of us in the absence of the other. The 
boiling-point of bromnaphthalene, as determined with the 
helium thermometer, is also very uncertain, because the 
position of the mercurv was not at all stable, probably ou 
account of the difficulty of obtaining rapid and smooth 
boiling of the liquid. Vet, even if these values are not 
taken into account, the differences are very remarkaUe, 
especially with quinoline, and the agreement with Wiebe's 
result is also not quite satisfadory. Part of these differ- 
ences may be doe to impurity in the liquids used in the 
jacket. Pains were taken at the beginning of our esperi- 
ments to have them quite pure, but as the values shew, 
apparently, a tendency to rise, it may be that continaout 
boiling produced slight decomposition. In the case of 
bromnaphthalene this is more than possible. If more 
time had been at our disposal we should have tested the 
purity of our substances during the operations. As it is 
now, it would be unwise to draw conclusions from our 
figures about the exad behaviour of any of the gases used 
at high temperatures. The coefficients of expansion be^ 
tween o** and xoo*' found for argon and helium agree very 
well with the values usually found for gases, and there is 
no indication of anything extraordinary happening to 
these gases at high temperatures. When areon ther- 
mometer I. was heated in the vapour of qomoline, a 
remarkable expansion of the gas was observed, continuing 
for two hours until a maximum value was reached ; this 
gave an apparent temperature of 243*5'' for the boiling- 
point of quinoline. On cooling the thermometer, how- 
ever, it was found to be cracked, and some drops of 
quinoline were noticed inside the bulb. The meaanre- 
ments made in this case were therefore rejeded, and a 
new series was begun with argon thermometer 11., whydh 
gave a value about normal. How the quinoline ^tM 
have found its way into the bulb while an interior n^f^ion 
of about 970 m.m. existed within it, without OWs iffoa 
escaping rapidly at the same time, is not qnit<y^ f^. It 
may be the vapour passed through the crac^ \ ^^ tbe 
temperature was rather low, and that the cOJUt L^iM «ti 
closed by the later expansion of the glass, ibttf^ 

For completeness sake, we give io th/ , tibls 1^ 



CiibiiicalNiws»I 
Dec. 20, i89S« I 



Helium and Argon : their Places among the Elements. 



297 



boiling-points of the tame anbttances determined with a 
mercory thermometer, as calculated from Ramsay and 
Yonng's Cables. Bat the irregularities of the thermo- 
meters prevent our giving any definite numbers for the 
reduaion of those tables to accord with any of the gas 
thermometer scales. A d'lrtA comparison, such as was 
executed by Wiebe and Bottcher, with a mercury thermo- 
meter of known constitution, like the Jena glass thermo- 
meter, would have been desirable. Differences of 
boiling-point resulting from impurities would have affe^ed 
both thermometers in the same wav, and would have 
enabled us to ascertain how much of the differences found 
resulted from that source of error. But here also want 
of time prevented our extending our programme beyond 
cbe limits fixed beforehand. 

Notwithstanding the incompleteness and want of per- 
§t€t\on of our work, we do not hesitate to publish our 
results; the difiSculties to be overcome in experiments of 
this kind are serious, and we did not make it our objed 
to obtain results of remarkable accuracy. The real mo- 
live of the work was to discover whether argon and 
helium show extraordinary behaviour at high temper- 
lores, or not, — and our results apparently establish the 
U6k that they do not. Their behaviour, so far as ex- 
pansion is concerned and within the limits of temperature 
which we ifsed, is apparently the same as that of so-called 
perfed gases or mixtures of them. 

Finally, it is a great pleasure to record our hearty ap- 
preciation of the kindly assistance of Professor Ramsay, 
at whose suggestion, and under whose supervision, these 
experiments have been conduced. 



HELIUM AND ARGON: 

THEIR PLACES AMONG THE ELEMENTS. 

By R. M. DBBLBY. 

Thb discovery by Lord Rayleigh and Professor Ramsay 
of two new elements having small atomic weights has un- 
doubtedly had the effed of greatly shaking the confidence 
of chemists in the periodic classification of the elements. 
Indeed, a disposition is often shown to place the Periodic 
Law altogether in the background and put undue 
faith in physical evidence, which is admitted to be incon- 
clusive. 

Although we cannot hope, in the present state cf our 
knowledge, to pronounce a definite opinion in favour of 
any one of the hypotheses advanced, it may not be out of 
place to review the fads from the standpoint of the 
Periodic Law. 

In Table I. all the best known elements are placed in 
the order of their atomic weights. To bring elements 
having similar properties into the same vertical lines, it 
has been necessary to leave many blanks. For instance, 
on the first line sixteen such blanks have been left, hydro- 
gen and helium falling on the last two spaces. 



** Every element,*' according to Mendeleeff (** The 
Principles of Chemistry,'* vol. ii., p. 33^, ** occupies a 
position determined by the group and series in which it 
occurs. For instance, Se occurs in the same group as 
S«>32 and Te = ia5, and in the same series as As ays and 
Br a 80; hence the atomic weight of selenium should be 
|(33-f x25+75-h8o)«78, as it is in reality." ** In this 
manntr it is potsibU to fonttll tk§ propgrtiis of still mn- 
known ilimsnts.** As Mendeleeff does not arrange the 
elements as they are placed in the first three lines of 
Table I., his argument does not apply to them. Indeed, 
he expressly omits elements having atomic weights 
smaller than aluminium from his calculations, and calls 
them typical tUmtnts, We must not, therefore, suppose 
that because argon and helium do not fall satisfadorily 
into his system that his arrangement is altogether wrong. 
These elements should fall among his typicaTiltmints, the 
classification of which is admittedly imperfed. Even as 
placed in Table I., grave fault ma^ be found with the ar- 
rangement. Hydrogen, althoush it may be conveniently 
classed with F, CI, Br, and I, is a metallic element. 
Beryllium and magnesium may also, with some reason, 
be placed in the column with zinc and cadmium, and 
lithium and sodium with copper and silver. There is 
consequently grave doubt whether the blank spaces in the 
first three lines are really blanks for elements not yet dis- 
covered. It would be rash to suggest that there are six- 
teen elements having smaller atomic weights than hydro- 
gen, for instance. 

I have elsewhere* shown that there are good reasons 
for supposing that no such blanks really exist, the typicai 
elements occupying the whole of the first line above that 
commencing with potassium, as in Table II. 

In my paper published in 1893 I showed that there was 
a blank for om element between H and Li. To this ele- 
ment I gave an atomic weight of about 2*5 (p. 86x). If 
the element be monatomic, this is about half as large as 
it should be ; but if diatomic, it is not far wrong. Pro- 
fessors Runge and Paschen have suggested that helium !• 
really a mixture of two gases, but the spedroscopic evi- 
dence cannot be regarded as very satisfadory. 

The difficult]^ of placing argon in position in the 
Periodic Table is, however, much greater. Is it mon- 
atomic or diatomic ? If monatomic, as is generally sup- 
posed, its atomic weight would place it between potassium 
and calcium— a position which would not agree with our 
present reading of the Periodic Law {Naturit Sept. 26, 
1895, p. 537). Its refradion equivalent also indicates 20 
rather than 40, and places it between fluorine and sodium, 
as shown on Table II. The only argument supporting 
the monatomic view is that derived from a consideration 
of the ratio of specific heats. This is often regarded as 
conclusive. Such, however, is not the case. Mr. J. W. 

* *' A New Diagram and Periodic Table of the Elenentt ** (Trtmt, 
Chem. Soe,, 1893); ** The Oxides of the Blementt an<l_the Periodic 
Lmw*' {Trans. Chem, Soc.ti9^ 
the Elements and the Periodic 



1894); **Tbe Refradion BqotvalccU of 
lie Law " {Trans, Chtws, Soc., 1894)* 



Tablb I. 

-.— — -. — — ^- — -- — — -. — -H He 

LiBe- — — — — — — — — — B CNOPA 

NaMg— — — — — — — — — — Al Si P SCI — 

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Qa Qe As Se Br — 

Rb Sr Y Zr Nb Mo — Ru Rh Pd Ag Cd In Sn Sb Te I — 

CtBaLaCeDi — — — — — — — — — — — — — 

— — Yb — Ta W — Os Ir Pt Au Hg Tl Pb Bi — — — 

__-«Th— U — — — — — — — — — — — — 



















Tablb II. 


















H 


He 


Li 


Be 


B 


C 


N 





F 


A 


Na 


Mg 


Al 


Si 


p 


S 


CI 


(?) 


K 


Ca 


Sc 


Ti 


V 


Cr 


Mn 


Fe 


Co 


Ni 


Cu 


Zn 


Qa 


Qe 


As 


Se 


Br 


(?) 


Rb 


Sr 


Y 


Zr 


Nb 


Mo 


? 


Ru 


Rh 


Pd 


Ag 


Cd 


In 


Sn 


Sb 


Te 


I 


(?) 


Cs 

? 


Ba 

? 


La 

Yb 


Ce 

? 


Di 
Ta 


? 
W 


? 

? 


? 
Os 


? 
Ir 


? 
9t 


? 
Au 


i. 


? 
tl 


? 

in> 


i 


? 
? 


? 


0) 


? 


? 


? 


Th 


? 


u 


? 


? 


? 


? 


? 


? 


? 


? 


? 


? 


? 


(?) 



sgS 



/ Cbbmical NBWB, 
I Dec. 10, 189$* 



Capstick iSci4nci Prognss, 1895, vol. iii., p. aSx) says :— 
*' After all, in our present state of ignorance regarding the 
status of the atom in the molecule, the argument drawn 
from the ratio of the specific heats is little more than an 
argument from analogy. The question at issue seems to 
be just the sort of case where the argument may break 
down, for argon differs in such a remarkable way from all 
other known substances that it would be unsafe to deny 
the impossibility of further eccentricities in the dynamics 
of its molecule.** 

Under such circumstances would it not be well to 
follow the indications of the Periodic Law and refrac- 
tion equivalents rather than a doubtful theory concerning 
the dynamics of the molecule ? 



Technical Analysis 0/ Cyanide Solutions. 

After estimating KCNS and K4FeCy6, a simple caU»*^ 
lation gives the oxygen to oxidise organic matter. This 



ON THE TECHNICAL ANALYSIS OF CYANIDE 

WORKING SOLUTIONS.* 

By W. BETTEL. 

(Ooododed firom p. 287). 

4« Firrocyanidis and Sulphocyanidis* — In absence of or- 
ganic matter, I have found that an acidified solution of 
a simple cyanide, such as KCy, or a double cyanide (as 
KaZnCy4), t.#., solution of HCy, is not affeded by dilute 

{>ermanganate. On the other hand, acidified solutions of 
errocyanides and sulphocyanides, are rapidly oxidised — 
the one to ferrocyanide, the other to H2S04+HCy. 

aK4FeCy6+0+ HaS04» K6Fc2CyM+ KaS04+ HaO. 
aKCNS+2HaO+30a-2KHS04+2HCy. 

If now, the ferrocyanogen be removed as Prussian blue, 
by ferric chloride in an acid solution, the filtrate will con- 
tain ferric sulphocyanide and hydric sulphocyanide, both of 
which are oxidised by permanganate as if iron were not 
present ; by deducing the smaller from the larger result, 
we get permanganate consumed in oxidising ferrocyanide, 
the remainder equal permanganate consumed in oxidising 
sulphocyanide. 

The method of analysis is as follows (in presence of 
Mine) !— A burette is filled with the cyanide solution for 
analysis, and run into 10 or 20 c.c. N/ioo KaMuaOs 
strongly acidified with HaS04 until colour is just dis- 
charged. Result noted (a). 

A solution of ferric sulphate or chloride is acidified 
with HaS04 and 50 c.c. of the cyanide solution poured in. 
After shaking for about half a minute, the Prussian blue 
is separated from the liquid by filtration and the precipi- 
tate and filter paper washed. The filtrate is next titrated 
with N/ioo KaMnaOs (6). 

Let e ■> c.c. permanganate required to oxidise ferro- 
cyanide. 
Thena-6-c. 

(c) I c.c. N/ioo KaMnaOs ="0*003684 grm* K4FeCy6. 
(b) X c.c. N/ioo KaMnaOs-ooooxfizS grm. KCNS. 

5. Oxidisabli Organic MatUr in Solution* — In treating 
•prait tailings, or material containing decaying vegetable 
matter, I offer the following method for testing coloured 
Bolations :— 

{a) Prepare a solution of a sulphocyanide, so that i c.c. 

sulphocyanide = z c.c. N/zoo KaMuaOs. 
(6) To 50 c.c. solution add sulphuric acid in excess, 

and then a large excess of permanganate, N/ioo. 

Keep at 60 — 70® C. for an hour. Then cool and 

titrate back with the KCNS solution. 

Result O consumed in oxidising organic matter. 
» O „ „ K4FeCy6. 

„ O „ „ KC NS. 

* K Paper read before the Chemical and Metallorgical Society, 
Jobanneabarg, S.A.R., August, 1895. 



result multiplied by 9 will give approximately the amount 
of organic matter present. 

In order to clarify such organically charged solutions, 
I shake them up with powdered quicklime, and filter ; the 
solution is then of a faint straw colour, and is in a proper 
condition for analysis. In such clarified solution the 
oxidisable organic matter is no longer present, and the 
ferro* and sulphocyanogen estimations are readily per- 
formed. 

6. i4 /ifca/mify .—Potassic cyanide ads as caustic alkali, 
when neutralised by an acid ; the end-reaAion, however, 
is influenced to some extent by the hydrocyanic acid pre* 
sent, and is therefore not sharp. We can, however, esti- 
mate — 



By 



N/ro acid zoo f> KCy 



N/zo acid 7*9 ft of I^ZnCy4 
N/zo acid zoo ^ of zinc in 

KaZnCy4 
N/zo acid zoo f> of Zn+K 

in ZnKaOa 
N/zo acid the KaO in 
^ ZnKaOa 



With phenolphthalein 
as indicator. 

With methyl-orange 
as indicator. 

With phenolphthalein 
as indicator. 



It will be necessary to point out the decompositions 
which result from adding alkali, or a carbonate of an 
alkali, to a working solution containing cine. 

KaZnCy4+4KHO->Zn%Oa+4KCy. 
KaZnCy4+4NaaCOs+2HaO- 

-2KCy+2NaCy+2nNaaOa+4NaHC03. 

Bicarbonates have no adion upon potassic or sodic xinc 
cyanide. 

Potassic or sodic zinc oxide (in solution as hydrate) 
atts as an alkaii towards phenolphthalein and methyl- 
orange. 

ZnKaOa+4HCl-2KCl+ZnCla+aHaO. 

Calcic and magnesic hydrates decompose the double 
salt of KaZnCy4 to some extent, but not completely, so 
that it is possible to find in one and the same solution a 
considerable proportion of alkalinity towards phenol- 
phthalein, due to calcic hydrate in presence of KaZnCw. 

The total alkalinity as determined by N/zo acid with 
methyl-orange as indicator gives, in addition to those 
before mentioned, the bicarbonates. If to a solution con- 
taining sodic bicarbonate and potassic zinc cyanide be 
added lime or lime and magnesia, the percentage of 
cyanide will increase, the zinc remaining in solution as 
zinc sodic oxide. 

7. Firricyanidt BsHmation,— Thin is effeded by allowing 
sodium amalgam to ad for fifteen minutes on the solu- 
tion in a narrow cylinder, then estimating the ferro- 
cyanide formed by permanganate in an acid solution* 
Dedud from the results obtained the ferrocyanide wmd 
sulphocyanide previously found, z cc N/zoo perflton- 
ganate — 0*003293 grm. KeFcaCyxa. 

8. Sulpkidis,— It rarely happens that sulphides are 
present in a cyanide solution ; if present, however, shake 
up with precipitated carbonate of lead, filter, and titrate 
with permanganate N/zoo. The loss over the previous 
estimation (of K4FeCy6KCNS, &c.) is due to elimination 
of sulphides, 

z c.c. N/zoo KaMnaOs « 0*000 1 7 grm. HaS 
or — 

I i» »f »> «= 0*00053 y, KaS. 

The hydrogen alone being oxidised by dilute permanganate 
in acid solution where the permanganate is not first of all 
In excess. 

9. Ammonia, — If sufficient nitrate of silver be added to 
a solution (say 10 c.c.) to wholly precipitate the cyanogen 
compounds and a drop or two of normal hydrochloric be 
added in addition, the whole made up to zoo c.c, and 



C SIII6AL News,) 
Dec.20, xSgs. I 



Boiling-point and the Genesis oj the Elements. 



2J99 



shaken, then filtered, and zo c.c. filtrate distilled with 150 
ac. water from a tubulated fiask, and the steam condensed 
in a Liebig*8 condenser (glass), the ammonia coming over 
may be readily estimated by colour test with Nessler solu- 
tion and comparison with distilled water free from am- 
monia and standard ammonic chloride solution containing 
o*oz m.grm. per litre, treated with Nessler solution. 

Then 10 c.c. taken diluted to 100 c.c. 

10 „ from 100 c.c. = i c.c. original 

= 1000 m.grms., then every 1 c.c. standard solution 

of ammonic chloride taken ■■O'ooi per cent 

NH3. 

Urea, Qxamidi, and Formates,—! am still investigating 
a method for the determination of these substances. 

Although these rea^ions and processes take some time 
in describing, the 'whole of the operations can be per- 
formed ivitbin one hour, and once the operator has a 
g radical knowledge of the process, the results, provided 
e is sure of the accimicy of the titre of his stock solu- 
tions, Inre most accurate. Most valuable information can 
in this way be obtained. • •! give «• few^ instances of the 
analyst£of working solutions : — 

X. Solutioii^ \origirf8flly KCy) in' contad with clean 
pyrites from Robinson concentrates for twenty- eight 
months ynth a^imited ^u^tly of air t— • • 

Per cent. 

JPotassid ferrod^anMe .'..•'..•.. 0*77 

iPotassic .sulphocyanide •• .. •• 0*14 

Pptasstc cyant)ft , .* * . .' . ." . . . • 0*005 

Pbtassic carbonate 0*33 

Potassre ' form'ifte, ' t>reS6nt but' not 

* 'estimated — 

AanmoniA .;•..•.."..'.. .. o'2i 

Sulphides, absent — 

Sulphate^, conbiderEd>le, not estimated — 

2. Solution from it€aiih^ dry crushed Robinson G. M. 
Company's pre without addition of neutralising agents 
after passing th tough' tine box : — 



^otassic c}rani\Ib.. " .. .. .. 

Potassic-zmc cyanide 

Potassic-iinc Hydrate. •' . . • • 

Potassic ferrocyanide 

^otassic sulphbtyawide . . . . 

Totassic bicarbonate 0*566 

Ammonia . .' * • • o-8o8 



Per cent. 
0*085 
0*25 
0*15 
0x74 
0*004 



3. As abov6, but with use of lime, not passed through 
zinc box :— 



Potassic cyanide, original 0*3 per cent 

Potassic ferrocyanide 

Potassi9 ferricy/inide . , ^ . . • • • • 

JPotassic sulphocyanide 

Ammonia 0003 

Calcic hydrate o'o67 



Per cent. 
0*24 
trace 

0*033 
o'ooS 



4. As in No. 2, but with lime in small quantity, after 
passing zinc box :— . . 

Potassic cyanide, original 0*45 percent 

Hydrocyanic acid 

Potassic-zinc cyanide . •• •• •• 

Potassic ferrocyanide 

Potassic sulphpcyanide 

Potassic sulphate 

Potassic bicarbonate 

Ammonia o"oo6 

It will be unnecessary to quote more analyses. A 
better way will be for chemists and cyanide works 
managers to adopt the process and compare results from 
analysis of their different solutions. 



Per cent. 
0*23 
0*04 
0154 
0*059 
0*004 
nil 
0-547 



APPARATUS FOR THE ESTIMATION OF 

SULPHUR IN IRON. 

By E. J. READ, B.A. 

In the estimation of sulphur in iron the following 
apparatus is very efficient and convenient, and could 
probably be. used for other purposes: — 

The sample is placed in A, the acid in B. The side-tube 
of A is connedted with the wash- bottle c, to which a cal- 
cium chloride tube D, filled with glass beads, is attached. 
The tube of o dips a regulated distance below the surface 
of the absorbing liquid, so that this is forced up among 




the beads by the passage of the evolved gas, and a most 
efficient absorption is obtained with the use of only a 
small quantity of absorbent. If the inlet tube of c dips 
below the surface of the liquid, it must be raised before 
disconnedling the apparatus, to prevent loss of liquid. 
The operation is preferably conduced under reduced pres- 
sure, and a current of pure air may be run through the 
apparatus at the conclusion to sweep out the remaining 
traces of gas from a. 



BOILING-POINT AND THE GENESIS OF THE 

ELEMENTS. 

By C. T. BLANSHARD, M.A. 

In a late number of the Chemical Nbws (vol. Ixxi., p. 
285) I drew a parallel between the elements and certain 
organic compounds, establishing a connexion between 
melting-point and periodic groups on the one hand, and 
melting point and strudture on the other. In the following 
article I hope to show that the physical property of vola- 
tility is equally valuable as a clue to the relationship of 
the elements to one another. 

Data as regards the boiling-points of elements are still 
very defedive ; but, if we examine into the elements 
group by group, we shall soon see that definite laws of 
volatility hold. Thus we have in— 



30O 



Boiling-point and the Genesis of the Elements. 



f CMITil ll«Wt 
1 Dce.10, ttgs. 



Oroap. 


Blemeot. 


B. p. out 


ObM 


I. 


N« 


74a« 


Pennan. 




K 


«f »" 


Perman. 


11.0. 


Zn 


940- 


VioUe. 




Cd 
Hg 


1700 
770° 

ax3® 
357° 


Carnellej. 
Regnault. 



Meao ditL • • 191* 
In Groapt II., III., Ac, there are not data enough. 
Group. Blement. B. p. DUL 



VI. 



vn. 



N 
P 
As 

Sb 
Bi 

O 

S 
Se 

Te 

F 
CI 

Br 

I 



-194^ 

+289* 

360° 

1440° 



483* 

xo8o<' 
340** 



1700" 
Mean •• 496* 
-i8i<» 



+448** 
680* 



629* 
a3a* 



Mean .. 434^ 



? 

? 

-34° 

+^° 

184" 



9f 



lai' 



Wroblewski ; Olsxew- 

Bid. 
Dalton; PelleUer. 

Eogel. 

Camelley ft Williams. 

Mensching and V. 
Meyer; Bilta and 
V. Meyer. 

Okaewtld; Wroblew- 
ski. 
Kegnanlt 

CanieUey. 



Regnanlt. 

Pierre ; Stat ; ?an der 

Plaatt. 
Ramsay and Young. 



Mean .. X09P 



The values are from Landolt and B5mstein, '* Physik* 
alische-chemische Tabellen," 1894; except that for iodinoi 
which is from the last edition of *• Watts' Did. Chem.** 

From the above tables we may fsirlv induce the fol- 
lowing laws for the elements regarding boiling-point : — 
X. u the metallic groups (1. #., I. to IV. inclusive) the 
volatility varies diredly as the atomic weight, 
whilst the differences between the successive 
boiling-points are more or less constant. 
2. In the non-metallic groups (i. #. V. to VII. inclusive) 
the volatility varies inversely as the atomic weight, 
whilst the differences between successive boihng- 
points alternate to a marked degree. 
' 3. The mean di£Ferences gradually increase up to Group 
v., or group of the highest general atomicity, and 
then again gradually diminish. 
Let us now, with these fads in view, see what main- 
tains in various groups of organic compounds, taking some 
of leu, others of grMter complexity. 

Karl Windisch, in his '* cesiehungen zwischen den 
Siedepunkt u. der Zusammensetxuns Chem. Verbindun- 
gen," Berlin, 1889, quotes the researches of the following 1 
(the abbreviations are those used in ** Watts' Didionary") 
—Kopp (A. 41, 79 ; A. Sopp. 5, 321 ; A. 96, x ; 50, 79 ; 
Schorlemmer (A. 161, 28x); Linnemann (A. 163, 41); 
Hanuch (A. 115, 36); Schmidt (B. 5, 597; 6, 498); 
Michaelis (B. 8, 499); Goldstein (j. R.); besides Nau- 
roann, Scbreiner, Henrv, Deoxel, Sabseneyeff', Kahlbaum, 
Staedel, and Mills. He finds that all these researches 
point to the comparative constancy of the diffmncts 
between the boiling-points in various organic series* Each 



organic series, he shows, has iu own eonslant difiereoc« 
for every increment of CHj. Thus for (i) 25 akobols bt 
finds the average difference to be x9-5^ ; (2) 71 hxtf adda, 
average difi*. b 2V9P\ (3) mercaptans, average diff. « agP. 

Windisch remarks on these figures that ** the dtfEerenoet 
in nearly all cases are very near the average dlfl ef en c ca 
pven." But the fads reaUy point to a different and moA 
mteresting conclusion. 

I will take certain org^c series which are tolerabhr 
complete at to boiling-points, bcwides being well aatheati- 
cated. The temperatures are from Vidor Meyer and Paol 
Jacobson, ** Lehrbuch der organ. Chemte " (Vett and Co., 
Leipsig, 1893). I have added the differences, aeleding 
only the norwud compounds to base them iqpoo. 

x. Normal Pmaffint. 

FbnBUnU B**p« I/iffi 

c4H,o ; ' 

36 

CsHu 37 

3* 

C6H,4 69 

CyHrt 98 ^ 

CsHis XS5 

C9HJ0 X50 

n 

CioHaa •• •• •• •• •• 173 

23 

CnHs4 •• X9S 

19 

CxaHiS 2x4 

20 

CxsH,8 234 ^ 

X8 

CmHjo 252 

x8 

CxsHaa •• 270 

Ct6H34 287 

x6 
C17HJ6 3<^ 

H 
CisHjs 3«7 

Avenge •• 23*3 

2. Normal Primarf Akokolu 

FonBoU. B.-p. Di& 

CH3.OH .> •• & * 

St 

CaHs.OH 78 

19 

CSH7.OH 97 

20 

C4Hg.0H •• XX7 

2X 

C5HII.0H X38 

C6H,3 0H X57 

19 
C7H1S.OH •• X76 

X9 
C8H,7.0H 195 

x8 
C9H19.OH 213 

x8 
CioHai.OH 23X 

Average • • X9*5 



CRBMICALNBWft,! 
Dec. to, 189s. I 



Chimical Researches and Spectroscopic Studies. 



301 



$• Normal Primary Aldihfds, 

Fonnnla. B.-p. Diff. 

CHs.COH 

CaHj.COH 

C3H7.COH 

C4Hg.C0H 

C5H11.COH 

C6H,3.COH 



21 


28 


49 
73 


34 
29 


128 


26 


155 


27 

16? (25?) 



C7HX5.COH 171? 

Average • • 26*5 
4. Normal Fatty Acids, 



FormolA. 



H.COaH .. 
CHs.COaH 
CaHj-COaH 
C9H7.COaH 



B.-p. Diff. 

• o 

XOX 

zz8 



Z62 



C4H9.COaH Z85 

CsHit.COaH .. •• •• .. 205 

C6H,s.C0aH 223 

C7Hi5.COaH 236 

Average •• 
5. Primary Ethyl Bstirs. 



17 
X3 

21 

23 
(eiceptional). 



20 
18 
13 

z8 



Formula. 
HCOa.CaHs .. 
CHaC0a.CaH5 
CaH5COa.CaH5 
CsHyCOa-CaHs 



B.-p. Diff. 

o o 

55 



C4H9COa.CaH5 
C5H„COa.CaH5 



77-5 
99 

Z2Z 



22*5 
21-5 
22 



145 
167 



24 
(exceptional). 



CcHiaCOa-CaH, 187 

CyHisCOaCaHs 206 

CsHiyCOa-CaHs 2275 

Average . • 
6- Normal Primary Mircaptans. 



22 

20 

19 
21-5 

21'5 



Fonnola. 
CH3.SH •• •• •• . 


B.-p. 

• •• 6 


Diff 




C«H>.SH.. •• •• • 


• •• 36 


30 


CSH7.SH 

C4H0.SH • • t • ■ • • 


. •• 67 

. .. 97 


3X 
30 



Average 



303 



7* Normal Primary Kitonts, 



Formula* 

(CH3)a.C0 •. •. 

(CaH5)a.C0 •• .. 

(C^Uyh.OO .. .. 

(C4H<,)a.C0 .. .. 

(C6H„)a.C0 .• .• 

(C6H,5)a.CO .. .. 



B.-p, 

o 

56 

X03 

144 
181 
227 
264 



Diff. 

o 

47 
4X 
37 

46 
37 



Average • • 42 

In the above aeries we notice : — 
z. Following Windiach'a method, the average dififer- 
encea in boiling-point are as follows : — 

Mean diff. 

1. Normal primary acida.. •• •• z8 

2. I, „ alcohols •• •• Z9*5 

3. v n ethyl esters • . 2z*5 
4* I, ,t paraffina •• •• 23*3 

5. I, I, aldehyde •• •• 26*5 

6. „ „ mercaptana •• 30*3 

7. „ n ketones •• •• 42 



2. The more complex the members of any series, i,$,f 
the more they deviate from the simple stmAnre of the 
water type, the greater the mean difference. 

3. In all the above series the differences alternate with 
more or less regularity ; bat in the series of least differ- 
ences the alternation is least, the differences approaching 
a constant ; whilst the series of greatest differencea show 
the greatest alternations. 

In all organic series the volatility varies inversely as 
the atomic weight. 

With the above>mentioned exception, the laws relating 
to the difference of boiling-point of organic compounds, 
and the alterations of the same, show a close connexion 
with Laws z and 2 applying to the elements. 

A comparison of the data so far brought to bear on the 
subjeA and the laws induced from these data, leads us 
to the conclusion that, of the elements. Groups I. to IV. 
—of general valency one to four — are less highly evolved 
than Groups V. to VII.— of increasing valency with 
regard to oxygen, and of decreasing valency with regard 
to hydrogen. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By JEAN SBRVAIS STAS. 

(Contiooed from p. a86). 

On thi Mtthods used to ascertain whether Solid Bodies 
were Present in or Absent from Chlorate ^ Perchlorate, 
and Chloride of Potassium, 

To verify the absence or presence of iron, manganese^ 
copper, aluminium, and silicon, in chlorate, perchlorate, 
and chloride of potassium, I argued from the following 
fkas:— 

Chlorate and perchlorate, when dissociated by the 
adion of heat in a pure polished platinum dish, are 
clearly transformed into chloride and oxygen without 
liberating a trace of chlorine. The evolution of chlorine, 
deteAed bv all chemists during the decomposition of thesto 
salts by the adion of heat, is due to the pretence of 
foreign bodies in the compounds submitted to dissocia- 
tion, and especially to the presence of iron, manganese, 
copper, aluminium, or silicon.* 

* Id a memorandom iddedto the cbftpter on the " t^reparitioo of 
Pare Chlorate, Perchlorate, and Chloride of Potaujomr I dcaciibo 



30i 



Chemical Researches and Spectroscopic Studies. 



{ 



(■pancALllBwt,! 
Dec so, 1895- 



FuMd chloride of potatsium is colourlisSt or more or 
lets colotred nd^ fink, or gngn, according as it is free 
from or contains iron, manganese, or copper. 

When heated beyond its fustng-point, colourless 
chloride of potassium — except it contains aluminiam, 
silicon, or calcium—volatilises without leaving a trace of 
residue. 

If the quantity of aluminium and silicon, in the form 
of aluminous silicate or silica, exceeds about i-50ooth of 
the whole in weight, the chloride of potassium when 
melted immediately shows brilliant specks floating on 
the liquid, caused by alumina or silica, or silicate of 
aluminium. In the other case, one only sees the bril- 
liant specks appear on volatilising chloride b^ heat, 
when the proportion of alumina or silica, or silicate of 
aluminium, is brought to about 1.5000th of the weight of 
chlorine. 

. II the silicon is in the chloride in the form of silicate 
of potassium or sodium, as is generally the case, the 
chloride when melted is a homogeneous liquid, even 
though the proportion of silicate be raised to a consider- 
able percentage of the weight. 

Dull platinum, and even this metal when polished, are 
wetted by melted chloride of potassium. Thus, when 
volatilising a chloride containing either silicate of 
potassium or silicate of sodium, you may see that— in 
proportion as it evaporates — the chloride leaves concen- 
tric circles of solid silicate, which keep increasing in 
thickness. 

The appearance of these concentric circles is so con- 
stant that one can rely on them, as I have done during 
the preparation of pure chlorate, to judge of the degree 
of purification as regards the elimination of silica com* 
bined with potassium and sodium. 

When applying this method of research to the chloride 
obtained from so-called pure chlorate of potassium from 
chemical manufadories, I have relied on the same rings 
to show me the large quantity of solid matters left on 
evaporation. 

To verify the above fads, I have volatilised the chloride 
of potassium in a concave lid of a large pure platinum 
retort with wide flat edges, holding 10 or xa grms. of 
melted chlorate. This lid rested by its border on a ring 
made of very thick platinum wire, supported by three 
blocks of fire-clay. These blocks were arranged so as to 
form a passage shut on one side, opened on the other, in- 
tended to hold a coal-gas blowpipe worked by bellows, 
and to serve for carrying off the produds of combustion. 
The coal-gas and air blowpipe was arranged so as to give 
the highest possible temperature at the centre of the 
platinum lid, whilst raising its flat rim to a red heat so as 
to unite it to the ring which supported it. The flat rim 
completely covering the ring, the produds of combustion 
could not escape around the dish, and were obliged to 
pass away by the upcast channel. 

When working the apparatus in a closed room, the air 
of which has been purified by remaining still for at least 
twelve hours, one can go on with the volatilisation of the 
chloride without it being necessary to place, at a certain 
distance above the lid, a sheet of platinum to prevent the 
dust, known to be always in air in motion, from falling 
into the chloride. I will add that I have proceeded in 
this manner during the numerous qualitative analyses I 
have made, as well for ascertaining the degree of purity 
of the chloride got by dissociating so called pure chlorate 
supplied by dealers in chemicals, as to judge of the state 
of progress in purifying the chlorides got from the decom- 
position of those chlorates of potassium. 

When I have been makins a quantitative analysis I 
have taken care to suspend, by a platinum wire, a large 
sheet of this metal in a very inclined position, and near 
enough to the surface of the dish to diminish the current 
which exists whatever one may do, and to prevent the 
projedion into it of foreign bodies by draughts. 



the method 1 used 10 aBcertain whether chlorine were present in or 
absent from oxygen prodaced by the decompotitioa of tbtolately 
pure chlorate an perulot ate of potaMium by heat. 



By regulating the blowpipe, both for the amount of gas 
burnt and for its position, one can volatilise in free air 
about 10 grms. of chloride of potassium in from eighteen 
to twenty minutes, by the method I have just described. 
On the other band, it requires at least thirty minutes when 
placing a large sheet of platinum at a great inclination 
above and near the surface of the evaporating dish. In 
this case a certain part of the volatilised chloride is depo- 
sited in a crystalline, transparent, and colourless state, in 
the centre of the sheet, surrounded by a snowy border. 
One could use this deposit for obtaining chloride free 
from all solid bodies, if it were not easier and more cer- 
tain to obtain it free from all solid bodies, and from the 
sodium of the air, by the method described above, which 
I have twice done on a large scale, as I shall describe 
further on. 

I have compared the result arrived at by this quick 
method with that very much longer one I described in my 
** New Researches on the Laws of Chemical Proportions,** 
and which consists in performing the volatilisation in a 
platinum boat, placed in a porcelain tube covered inside 
with platinum, and raised to white heat, and causing a 
current of dry- nitrogeir to pass through it. * 

When applying purified nitre with the greatest care to 
part of the chloride in which I- had found, by the latter 
method, 0*00056 grm. of solid residue, I found by the 
new method o'Ooo6or grm*. per 10 grms. experimented 
on. Both methods are evidently of equal value. 

To finish this description i ought to add that experience 
has shown me that one cannot rely on the weight of the 
platinum vessel keeping constant when heated tn the coat* 
gas and air blowpipe. I haVe oftten found the 'weight 
slightly increased, but more often decidedly decreased. 
When one wishes to git ii accurate results as possibloi 
one roust weigh the platinum vessel on which one has 
evaporated the chloride, ahd weigh i( again after having al- 
lowed hydrofluoric acid mixed with its own volume of water 
to remain in the cavity in the cbld; and then hydrochloric 
acid diluted to i-20th ; and lastly, after having washed it 
enough with pure water. Under these conditions pore 
platinum does not change in weight. 

By taking the difference between the first and second 
weight of the platinum vessel when heated to white heat 
and then cooled under a bell-jar in air of the same dry- 
ness, as the weight of the residue, one is bound to get a 
result as accurate as a research of this nature permits of. 

To look for calcium in the chlorate and chloride of 
potassium I employed speArum analysis ; but the quan- 
tity of this metal being seldom enough to be seen in the 
compounds put into the flame, I have, after having trans- 
formed the chlorate into chloride, volatilised it down to 
a few hundredths of its volume. I then put the residue 
into a Bunsen flame or into an oxyhydrogen blowpipe 
flame, to look for the charaderistic lines of the calcium 
spedruro. By doing this, one is easily convinced of the 
extreme difiSculty of obtaining chlorate or chloride of 
potassium absolutely free from calcium. 

On the Preparation of Chlorate of Potassium. 

After having ascertained that, by means of a very dilute 
solution of sulphydrate or hydroxide of potassium, one 
can transform the silicon and sodium in chlorate of potas- 
sium to a silicate^ I have, on two different occasions, pro- 
ceeded with the purification of commercial chlorate, 
which I had submitted to a preliminary analysis, working 
the first time on three kilogrms, and the second time on 
two kilogrms, of this salt from different sources. The 
chlorate to be purified contained irdn, manganese, copper, 
a great deal of sodium, silica, aluminium, magnesium, 
calcium, chloiides and sulphates, as well as organic dust. 
I effeded the purification m the following manner : — 

To a sufficient quantity of water; kept at about loo* in 
two large porcelain dishes, was added, to saturation, the 
powdered chlorate, and the solutibn was filtered to get 
rid of the dust in suspension. The filtered liquid, having 
been again brought to about xoo°, received an excess of a 



Cbbmical Riwi, 
Dec. ao, 1895. 



} 



Chemical Researches and Spectroscopic Studies, 



303 



dilate solution of salphydrate of potassium,* and was 
filtered immediately. On suddenly cooling it the solution 
precipitated a salt in small fink flakes. The mother- 
liquor, which was coloured, was completely separated. 
The salt was put into a large shallow funnel, fitted with a 
clean linen plug, and a smooth ground-glass cover with 
a hole in it. The funnel was fitted on to a large fiask 
with two tubes communicating with a water-pump. After 
straining the salt in pure air it was sprinkled with iced 
water containing about one per thousand of sulphydrate 
of potassium, keeping the pump at work until the 
chlorate was rendered completely colourless. The 
sulphydrate solution was followed by pure iced water, to 
remove the alkali and foreign salts as much as possible. 

The colourless saline fiakes were finely powdered in a 
Wedgewood moitar, and the powder was replaced in the 
large funnel and washed afresh with pure iced water. 

The chlorate, when treated thus, had a very decided 
sodic reaaion. It was saturated with water at xoo^ The 
BoltttioD, not being clear, was filtered, and to the liquid- 
heated to re-dissolve all the chlorate which had been 
crystallised by cooling— was added a solution of sulphy- 
drate in sufiBcient quantity to give it an alkalins nacHon, 
The liquid was neither cloudy nor coloured, and the 
chlorate which was precipitated on suddenly cooling it 
was in fine colourless flakes. 

The salt was strained and washed with a wash-bottle, 
first with iced water containing one per thousand of 
sulphydrate of potassium, and then with pure iced water. 
The sodium lines were distinaiy visible on analysis, but 
by no means so clearly as in the case of the chlorate 
from which the salt was made. 

When dissolved in water it did not cloud a solution 
of chloride of barium, but it did very sensibly nitrate of 
silver. 

I repeated a third time, in porcelain, the treatment I 
have juftt described, and, although I was obliged to work 
in the soda-contamioated air of the laboratory, the 
chlorate showed the sodium charaderistics in a Bunsen 
burner so faintly that it was necessary to resort to spec- 
trum analysis before being able to detea with certainty 
the presence of sodium in it. 

The solution of salt no longer clouded nitrate of silver, 
but the chlorate, when decomposed by heat, evolved a 
sensible amount of chlorine, and the chloride formed 
from it— when volatilised by the method mentioned above 
—left a small residue in which I deteded the presence of 
silica, potassium, sodium, aluminium, and calcium. 

Having learnt, as I have described above, by prelimi- 
nary trials, that, by continuing the treatment in porcelain 

* The preparation of a solution of hydroxide and salphydrate of 
potasslnin, as free as possible from sodium, is a verv delicate opera- 
tion. I procured the compounds used in my researches by means of 
oxide of potassium made by Wdhler's method.-that is to say, by 
heating a mixture oi nitre and pore copper in excess, in a large 
copper crucible made by dedrohrus from pure sulphate of copper. 
The nitre came from nitrate purified for powder-making. I cryiul- 
lised it thrti times in a one per thousand solution of solphydrate of 
potassium, stven timet in a one per thousand solution of hydroxide 
of poussium, working in enclosed and purified air, in a large plati- 
num retort, and fcna ly twice in pure water. The nitrate, which was 
crystallised three times in the sulphydrate converted into chloride, 
Was completely volatilised ; but when put into a flame it showed, on 
spearum analysis, the sodium line with a comparatively great in- 
tensity. It therefore still contained some sodium, without doui:t in 
the form of a nitrate. After having crystallited it four times more in 
water made alkaline tty hydroxide of potassium, and twice in pure 
water, it gave the flame a blue tint slightly tinged with violet, and 
showed the sodium line very faintly until it was completely vola- 
tilised, which was done with very great rapidity. 1 must confess 
that when working with nitre already purified 1 was not able to pre- 
pare nitrate of potassium absolutely free from sodium by means ot 
successive crysUUisations in alkaline and pure water. But, judging 
by the faintness of the sodium line, the amount of sodium held by the 
nitre did not exceed the amount often found in dry air, when undis- 
turbed for eighteen hours in a very large room. The solution of 
hydroxide otpoUssiom resulting from the absorption of water by 
oxide of potassium always contained copper, owing to the a^ion of 
copper on nitre. The separation of copper from the solution was 
tfleAed by means of a proper quantity of bydrotulphuric acid. The 
transformation of hydroxide free from copper into sulphydrate, and 
the preservation of the hydroxide and sulphvdiate solutions, are done 
in cfcted platinum vessels, to protect them from contact with the air. 



or glass tubes, one introduces as much silica and sodium 
into the chlorate as the use of sulphydrate of potassium 
enables one to eliminate from it, I continued the opera- 
tions entirely in platinum, and, as far as possible, in en- 
closed and purified air. For this purpose I dissolved it in 
boiling water in a large platinum retort with a lid, ths 
neck of which contaimd a large cotton plug washed with 
a mixture of ether and alcohol^ dried^ and then soaked m 
a saturated solution of chlorate of potassium. 

As soon as the water was saturated the liquid was made 
alkaline by sulphydrate of potassium, and immediately 
cooled by plunging the retort into running cold water, and 
finally into snow. By inclining the retort to one side the 
mother-liquor was drained off by the opening in the neck 
of the dome, from which the cotton plug soaked in the 
chlorate solution was removed. By plunging a hard 
rubberiube, treated successively with 'a dilute boiling so- 
lution of pure potassium with dilute acetic acid, and then 
with pure water, into the saline mass, the remaining 
mother-liquor was drawn by su^ion ; this was replaced 
several times with small quantities of iced water contain- 
ing hydrate of potassium, and then with pure iced water, 
until the ii<]uor was quite neutral to litmus-paper. 

After this fourth treatment, the salt, when introduced 
into a Bunsen flame, gave it a pale blue colour. At the 
time of n>aking this experiment the air of the large room 
in which I was working gave no trace of the sodium spec- 
trum ; nevertheless, after the introdudion of chlorate on 
the end of a loop of fine platinum wire recently heated 
to redness, the sodium line was seen, though very faintly. 

Several grms. of this chlorate were reduced to chloride 
by the adion of heat, and this was volatilised by the 
method mentioned above. When it was reduced to about 
i-iooth of its original volume, the residue began to form 
very weak concentric rings of silicate fusible at the 
highest temperature. On carrying volatilisation to com- 
pletion, the chloride was evaporated without depositing 
any brilliant specks, though a series of rings, very thin, 
colourless, transparent, and ver^ fusible, was deposited. 
These little rings, when heated in the oxy hydrogen blow- 
pipe, gave it a vioUt colour. SpeArum analysis of the 
flame enabled me to deted the presence of the sodium 
line, side hy side with the potassium spedrum, but the 
charaAeristic calcium lines were entirely absent, althongb 
the temperature was high enough to melt the platinum in 
which the chloride was volatilised. 

In face of this result I repeated the solution and crys- 
tallisation of the chlorate in water containing one per 
thousand of hydroxide of potassium, made from nitre as 
pure as I could get it. I washed the salt first in this 
same alkaline iced water, and then with pure iced water, 
working, as I have mentioned above, in a large room 
apart from the laboratory. 

The chlorate from this fifth treatment coloured a Bun- 
sen flame pure pale blue, and on spedrum analysis of the 
flame I could not see the sodium line any stronger than 
in air without chlorate. 

I once more reduced part of the sslt to chloride. Its 
dissociation was effeded without evolving chlorine. Ten 
grms. of absolutely colourless and neutral chloride were 
volatilised without leaving a trace of residue visible under 
the microscope, 

Fearing, nevertheless, the presence of traces of dust 
and alkali in this salt, I made the solution in almost 
boiling pure water, and I passed the saturated liquid 
through small filter-papers, m platinum funnels, purified 
with water acidulated by hydrofluoric and hydrochloric 
acids, and then with pure water. The filtered liquids 
were received into platinum vessels, all of which were 
placed on smooth sheets of glass, and covered with a bell* 
far, with a ground and polished edge and with its surface 
moist4ned, to stop contamination by dust. 

After filtration and carefully washing the filters with 
water, I was unable to deted on the surface of the paper 
the slightest trace of dust, or any deposit whatever. 

The filtered solution, which was no longer saturated a 



304 



Constitution of Pyrazole. 



iChihical fiiwt, 
I Dec. 20. 1895. 



boiling-point, was put back into the large platinum cm- 
cible, the neck of which reached very far into a flask, and 
was concentrated down almost to dryness, and then 
quickly cooled. The niother-liquor, although colouring a 
name pale blue and noi showing tht sodium line, was en- 
tirely separated. The chlorate was dried in the platinum 
crucible covered by a lid, the long neck of which reached 
far into a flask full of purified air, by placing the crucible 
in an air-bath heated to 100°. 

Out of five kilogrms. of commercial salt, worked upon 
in two operations, I only saved four hundred grms, of 
chlorate that I could consider pure, — that is to say, only 
eight per cent of the weight of salt used. 

I made, with the greatest care, an experiment on the 
chlorate obtained in each operation, to ascertain the 
quantity of solid matters left after evaporating the chloride 
made by dissociating it in a covered platinum retort. I 
took 5*007 grms. of chloride from the first chlorate, and 
8*190 grms. of chloride from the second chlorate ; in both 
cases the material experimented upon was volatilised 
without leaving a trace of residue^ I do not say ** weigh' 
abUt** hut not even visible under the microscope. 

These two researches, the execution of which was as 
laborious as delicate, enable me to state that under suit- 
able conditions, it is possible, contrary to my previous 
Opinion, to obtain chlorate, and therefore chloride, of 
potassium absolutely free from sodium and solid matters. 
(To be contiotted). 



PROCEEDINGS OF SOCIETIES. 

PHYSICAL SOCIETY. 
Special Meetings December i^th, 1895. 

Prof. RsiNOLD, Vice-President, in the Chair. 

Thb Resolution with reference to the change in the 
amount of the life-composition fee, passed at the Special 
General Meeting held on November aand last, was con- 
firmedi 



The Ordinary Meeting was then held. 

Dr. John Shield read a paper on "A Mechanical 
Device for Performing the Temperature Corrections of 
Barometer s.^^ 

The form of barometer to which the author has adapted 
his device is that devised by Dr. Colley ; it is intended 
for general laboratory use, and is capable of being read to 
within 0*1 m.m. The barometer tube can be moved in a 
vertical direAion, so that the lower meniscus can be 
adjusted to the zero of the scale. Attached to the baro- 
meter tube is a thermometer with a horizontal stem, 
passing in front of a scale which is fixed to the vertical 
■cale of the barometer. The graduations of this thermo- 
meter scale, with the exception of the one passing through 
the o^ C* mark on the thermometer, are inclined to the 
vertical, and are so spaced that the reading opposite the 
end of the mercury column of the thermometer gives 
diredly the correAion to be applied to the observed 
height of the barometer (BO in order to obtain the re- 
duced height (Bo) ; that is, the reading on the thermo- 
meter scale gives the value of B| (/3 -7)^ ; where fi and y 
are the coemcients of expansion of mercury and of the 
material of which the barometer scale is composed respec- 
tively, and t is the temperature. 

Mr. Boys admired the simple method the author had 
adopted for plotting the correAions, and said that he 
always felt that the trouble involved in applying small 
conedions ought, if possible, to be avoided, or the correc- 
tions would often be omitted. 

Mr. Appleyard advised the placing of the bulb of the 
thermometer within the barometer tube. 



iteMm 



,.-1 



Dr. Shield, in his reply, said as the barometi 
only intended to read to 0*1 m.m., the placing of the 
thermometer within the tube did not appear necessary. 

A paper by Prof. Rocker on " The Resistance of Vertical 
Earth-air Currents in the United Kingdom " was, in the 
absence of the author, read by Mr. Kay. 

In a paper read before the British Association, at 
Oxford, Dr. Schmidt stated that he had expanded the 
components of the earth's magnetic force in series, and 
had deduced expressions, two of which give the magnetic 
potential on the surface of the earth, in so far as it 
depends on (i) internal and (2) external forces. ** The 
third series represents that part of the magnetic forces 
which cannot be expressed in terms of a potential, but 
must be due to eleAric currents traversing the earth'a 
surface." 

Dr. Schmidt concluded that such currents amount on 
the average to about o'l ampere per square kilometre. 
The author has tested this conclusion, drawn from the 
state of the earth as a whole, by means of an examina- 
tion of the line integral of the magnetic force round 
a re-entrant circuit, taken in the United Kingdom. The 
necessary data have been obtained from the results of the 
magnetic surveys for the epochs 1886 and 1891, carried 
out by the author and Dr. Thorpe. Two circuits called 
the a and fi circuits were seledled, having their greatest 
extension north and south and east and west respedively. 
The work done by a unit magnetic pole on traversing 
these circuits was calculated for the epoch 1886 by means 
of the terrestrial lines found for that date, and also for 
the epoch 1891 by means (i) of the same lines when due 
allowance was made for secular change, and (2) of the 
independent set of lines found by aid of the 1891 survey. 
The same calculation was made for a third circuit (7) 
using, instead of the calculated terrestrial lines, the true 
values of the forces and delineations as deduced from the 
nearest stations. The following table gives the results 
in amperes per square kilometre : — 

a. /3. y. 

i886 -0*026 -0*004 — 

1891 fi) +o*ooi -0*005 — 

1891 (2) — — -0*008 

From these figures the author concludes that there is 
not, in the United Kingdom at any rate, a vertical current 
amounting on the average to 0*1 per square kilometre. 

Mr. Watson said a few words on the difficulty experi- 
enced in determining the line integral in South Wales, 
due to the presence of closed curves. 

The Society then adjourned till January a4tb, 1896. 



EDINBURGH UNIVERSITY CHEMICAL 

SOCIETY. 

Second Ordinary Meetings Monday, December and, xSgs* 

Dr. Mackenzie in the Chair. 

Dr. Macdonald read a paper on the <' Constitution of 
PyraMole," beins an account of the work done by himself 
at Jena, of which the following is an abetrad. 

It was pointed out that three constitutional formula 
had been proposed for pyrazole, and these by Knorr, 
Buchner, and Bamberger, modelled on the benzenej for- 
mulae of Kekul^, Claus, and Baeyer respeAively. For 
derivatives with a substituting atom or group on one of 
the nitrogen atoms an unsymmetrical formula accounts 
for all observed phenomena; but otherwise, according to 
results obtained by him in the Chemical Laboratory at 
Jena, each of the above-mentioned formtilae is in- 
applicable. 

A methylpyrazole, necessarily 3- or 5-methylpyrazoIe, 
which showed no trace of isomers, was prepared synthetic 
callv. Next both 3- and 5-methylpyrazole were prepared 
analytically by burning away, by means of permanganate 



ClUIIICAL NlWt, I 

D«c. ao, 189s. I 



Place Of Helium in the Classification 0/ Elements. 



305 



of potatb, the phenyl-group from i-phenyl-s-methyl- 
pyraxole and z-phenyl-5-inethylpyrazole respe^ively — a 
readioo which was found to go better on the introdndion 
of a nitro-groap into the benzene ring, and subsequent 
reduAion. These analytically prepared substances were 
both identified with the synthetically prepared methyl- 
pyrazole by the boiling-point and by the preparation of 
loar derivatives— the corresponding pyrazole carboxylic 
acid and nitromethylpyrazole, and the double salts with 
AgNOj and HgCla. Of some twenty derivatives of the 
ssmthetical produA, these four had been seleAed as the 
liest adapted for the identification. 

According to this result, the molecule is synthetical, 
and each of the three formulas — 

NH 



NH 



NH 

N,f^CH 

I y 

HC CH 





Bochoer'a. 



HC CH 

Bamberger*!, 



Koorr't. 
is impossible. 

The difficulty of disposing of the H atom, which in the 
above formulae is attached to a nitrogen atom, makes it 
hard to say what the correA formula may be. It seems 
that this H atom must move from atom to atom in the 
ring. As to whether it visits every atom in the ring, or 
only the two nitrogen atoms and the middle carbon atom, 
or the two nitrogen atoms merely, cannot at present be 
decided. 



Third Ordinary Mating, Monday , Dtamhtr gth, 1895. 

Dr. Mackbmzib in the Chair. 

Dr. Marshall read a paper on ** Of Heal Activity and 
Crystalline Form,*' of which the following is an abstrad. 

In an ordinary ray of light the vibrations take place 
successively in all possible diredions perpendicular to its 
axis. By certain means it is possible to restrid the 
vibrations to one particular plane. The ray is then said 
to be plane- polarised. 

This may be accomplished by means of certain crystals, 
anch as calc-spar or tourmaline, which have the property 
of double refraAion. 

While studying the adion of plane-polarised light on 
crystalline plates, Arago noticed that a plate of quartz 
cut at right-angles to the optic axis, rotates the plane of 
polarisation of light transmitted through it. He further 
noticed that some specimens of quartz rotate the plane of 
polarisation to the right, and some to the left. This re- 
markable phenomenon was carefully investigated by Biot, 
who deduced the following laws : — 

I. The amount of rotation is proportional to the thick- 
ness traversed by the ray. 

a. The roution effeaed by two plates is the algebraic 
sum of the rotations produced by each separately. 

3. The rotation is approximately proportional to the 
inverse square of the wave-length of the light used. 

Biot soon discovered that many organic liquids, solu- 
tions, and vapours also rotate the plane of polarisation. 

It was soon noticed that the optical adivity of crystals 
wafr a quite distind phenomenon from the optical 
adivity of liquids. Thus Herschel, by dissolving quartz 
in fused potash, found that the optical adivity disappeared. 
Herschel also observed that there was a connexion be- 
tween the diredion of rotation and the arrangement of the 
piagihedral faces on quartz crystals. Here the optical 
adivity is due to crystalline strudure. 

In the case of liquids, solutions, and gases, Biot*s ex- 
periments on oil of turpentine showed that here the 
^ optical adivity is due to individual molecules. 



Substances which are optically adive only in the solid 
state, such as quartz, sodium chlorate, sodium bromate, 
Schlipp's salt, cinnabar, &c., are without exception iso- 
tropic or uniaxial. Substances which are optically adive 
only in the liquid state, such as tartaric acid and ite 
salts, are all compounds of carbon. 

Pasteur carefully investigated the two optically adive 
tartaric acids. When in solution, they rotate the plane 
of polarisation equally, but in opposite diredions. The 
crystals are hemihedral and enantiomorphous ; though 
this is the case with all optical isomers, the converse is 
not true, since many substances are known which, though 
crystallising in forms devoid of planes of symmetry, are 
not optically adive in solution. 

Some substances, such as strjrchnine sulphate and 
rubidium tartrate, are optically adive both in the crystal- 
line state and when dissolved. 

Wyrouboff has studied numerous allied compounds, and 
has tried to apply Mallard's theory of the rotatory power 
of crystalline substances to solutions. He arrives at the 
following conclusions : — 

1. That the rotatory power of substances in solution, 

like the rotatory power of crystalline bodies, de- 
pends on the strudure of the crystalline molecule, 
as distinguished from the chemical molecule. 

2. In solution the crystal molecules are not broken up, 

and therefore there can still less be dissociation 
into ions. 



CORRESPONDENCE. 

ON THE PLACE OP HELIUM IN THE 
CLASSIFICATION OF ELEMENTS. 

To thi Editor of tht Chitnieal News. 
Sir,— In the CHSMrcAL News (vol. Ixxii., p. 291) Mr. 
Wilde accuses me of loose arithmetic and looser asser- 
tions. This charge is founded on a short report of some 
extempore remarks which I made at the Physical Society 
on November 22nd, during the discussion of a paper by 
Dr. Johnstone Stoney. 

My first impulse on reading that report was to write a 
letter explaining that it was inaccurate. On second 
thoughts I refrained, for the arithmetical mistakes were 
so obvious that I thought every reader who knew anything 
of the subjed would put them down as a reporter's or 
printer's error. The figures given were certainly not 
those which 1 wrote on the black board. If they had been 
corredly given there would have been little difficulty in 
understanding my previous statement, notwithstanding 
its very condensed nature. 

My objed was to show that if the two new gases of 
which helium is probably composed are really analogous 
to the alkaline metals, as Prof. Runge's photographs of 
the spedra seemed to indicate, there was no serious diffi. 
culty in placing them in the same group. It is evident 
that the difference of atomic weight between hydrogen 
and lithium is only 6 ; between lithium and sodium it 
rises to 16; and after two terms it again rises to 24. 
Subsequently it is probable that the difference is still fur- 
ther increased. There would therefore be no difficulty in 
supposing that the first difference might be less than 6. 

Excepting in their bearing 00 the position of helium, 
the views expressed by me are by no means new. As far 
back as 1853 I showed {Phil. Mag.^ May, 1853) that the 
atomic weights of several series of analogous elements 
differed by certain increments like those in the well-known 
organic series, and I drew special attention to the occur- 
rence of the numbers 16 and 24. In an address to the 
Chemical Sedion of the British Association, in 1883, 
sneaking of the atomic weights in Mendeleeff's table, I 
observed that " those in the vertical series differ from one 



3o6 



Chemical Notices from Foreign Sources. 



I Ohimical HWMt, 
I Dec 20» 1895. 



another, as a rule, by the before-mentiooed multiples of 8, 
namely, 16, x6, 24, 24, 2±, 24, 32, 32, the elements being 
generally analogous in their atomicity and in other che- 
mical charaders.'* 

I have no desire to discuss Mr. Wilde's ingenious spe- 
culations, whether in his paper of 1875 or that of 1894 ; 
and, as far as the position of helium is concerned, it 
would seem desirable to wait for further light on its 
natare.^I am, &c., 

J. H. Qlasstonb. 
t7, Pembridge Sqoare« 

Movember 17, 1895. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 

NoTB.->AJl dogrsM of tsmptratare are Centigrade unlets otherwise 
espresaed. 

ComtUs Rendut Hebdomadaires des Stances, de VAcademU 

aes Sciences, Vol. cxxi.. No. 22, November 25, 1895. 

M. Launelongue has been eleded a Member of the Sec- 
tion of Medicine and Surgery, viti the late M. Verneuil. 

On Para-ethoxyqainoleine. — C. Grimaux. — The 
author describes the preparation and properties of quin- 
etbol, CixHiiNO, its hydrochlorate, sulphates, and ni- 
trate. Quinethol is a weak base ; its salts with the organic 
adds are dissociated by water. By dissolving quinethol 
in sulphuric acid and adding two mols. of fuming nitric 
acid we obtain nitroquinethoT, CxxHxo(NOa)NO. It has 
feeble basic properties. Amidoquinethol, CxxHxo(NHa)NO, 
is obtained by reducing the nitro-compound with stannous 
chloride in a hydrochloric solution at a temperature below 
50^ It is easily diazotised, and yields tindlorial diazo- 
compounds. Quinethol has no aAiou upon intermittent 
fevers, and has no anti- periodic properties. 

Rapid Determination of Nitric Nitrogen in Vege- 
table Substances. — P. Pichard. — This paper will be in- 
serted in full. 

Action of Phenol upon Mercurous Iodide. — Maurice 
Francois. — At the temperature of ebullition the decom- 
position of mercurous iodide by phenol is limited by the 
3uantity(of mercuric iodide existing in solution. The 
ecomposition always ceases when xoo parts of liquid 
contain 275 grms. mercuric iodide. In presence of me- 
tallic mercury if a solution of mercuric iodide in phenol 
contains more than 2*75 grms. of mercuric iodide in xoo 
grms. of solution, there is found mercurous iodide. 

Manganese Silicide. — M. Vigoureux.— Manganese 
silicide has a metallic lustre, and is very hard, brittle, and 
perfeAly crystalline. Its specific gravity at 15° is 6*6. It 
IS unalterable in air and fusible in the reverberatory fur- 
nace. Fluorine attacks it at the ordinary temperature, 
forming white fumes of silicon fluoride. If heat is applied 
there ensues combustion, with flame and incandescence. 
Dry chlorine ads at 500" with lively incandesccence, sili- 
con chloride being evolved. Iodine and bromine read 
lets readily. Caustic potassawith the aid of heat attacks 
this compound energetically. Its composition is SiMna. 

Toxicity of Acetylene. — L. Brociner. — Acetylene 
exerts merely a very feeble poisonous adion, not more 
marked than that of the ordinary hydrogen carbides, such 
as formene, ethylene, or propylene. Animals exposed to 
the adion of mixtures containing considerable proportions 
of acetylene for several hours do not succumb if we are 
careful to operate in presence of a considerable quantity 
of oxygen, and to renew the gaseous mixture so as to pre- 
vent the produds of the animal's respiration from accumu- 
lating. 

Some Readtiona of Tartaric Acid and the Alkaline 
Tartrates. — L. Magnier de la Source.~If to a concen- 
trated solution of potassium acetate we add a relativelv 
small proportion of tartaric acid (though more than snf* 



ficient to precipitate with an equal volume of solution of 
potassium sulphate) there is no immediate precipitate. 
The addition of a mixture of ether and alcohol renders the 
precipitation more rapid, and the addition of acetic acid 
renders it immediate. 

Presence of Laccase in Fungi. — Em. Bourquelot and 
G. Bertrand.— Laccase exists not merely in green plants, 
but in such as are devoid of chlorophyll. 

Distribution of the Nitrogenous and Mineral Sub- 
stances in Bread. — There exists no more nitrogenous 
and saline matter in the crust of bread than in the crumb 
if both are brought to the same degree of dehydration. 
The baking of bread does not effed any destmdion of 
matter. There is a loss of fatty substances and an increase 
of saccharine matter, but the total weight does not vary 
to an appreciable extent. Dry bread does not contain 
more nutritive matter than the dry flour used in its pro* 
dudion. 

MISCELLANEOUS. 

Corrugated Packing Paper and Boards.— We have 
received, from Messrs. Bracht and Friedlaender, speci- 
mens of an improved packing material which they are 
introducing to the English market. From a careful 
examination we think that its use will be found very 
convenient and safe for packing breakable goods, as well 
as for forwarding samples for analysis, specimens of dry 
colours and other fine chemicals, eledros for the illustra- 
tion of books and journals, &c. The double corrugated paper 
is calculated to supersede other materials as an enclosure 
for phials, specimen tubes, and glasses, as it combines light- 
ness with great resistance to pressure and concussion. 
It is manufadured in a variety of colours and shapes 
adapted for various purposes. 

NOTES AWD QUERIES. 

Glass Cloth for Acid Filtering.— Will lome reader kindly aUto 
where the article known as glats cloth for acid filteriof porpotet can 
be obtained, and who are the nunufadarert ?— W. 



TO CORRESPONDENTS. 

H. P, y.—Vfc are of course aware of the two views you mootioa 
concerning the electrodes in voltaic cells ; but we cannot trace n^o la 
originally responsible for each opinion. 



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6 A 7, CR038 LANE* LONDON; E.G. 



"'dS!^.,^*') Investigations oj the Chemical History 0/ the Barley Plant. 



THE CHEMICAL NEWS. 



Vol. LXXII., No. 1883. 



INVESTIGATIONS OP THE CHEMICAL HISTORY 

OF THE BARLEY PLANT/ 

Bj C. P. CROSS mnd CLAUD SMITH. 

It it becoming evident that atefal research in matters 
agricultural mast henceforth take the form of physiological 
diagnoais. The investigation of crops in relation to soils 
and fertilisers has of course rendered incalculable service, 
and in this country the distinguished group who have pre- 
sided over the Rothamstead Experimental Station have 
done much to lay the foundation of sound scientific prac- 
tice. At this date, however, we have to confess that the 
fundamental problem of Asstmilation is, so far as the 
agriculturist is concerned, so much '* virgin soil.*' While 
experience and the vast accumulation of observations fur- 
nish more or less accurate impressions of the results uf 
the process, the process itself is one of those fadors of 
produdion which are still ** taken for granted." We may 
except, perhaps, from this general statement certain 
positive results which have followed the application of 
methods of seledion based upon observation of variations 
of particular produds of assimilation, such as the improve- 
ment of the sugar beet in relation to the produdion of 
sugar. But even here the methods pursued are empirical 
and involve no consideration of the adual mechanism of 
assimilation. 

Now that methods of more exad proximate resolution 
of mixtures of carbohydrates are in our hands, the time 
has arrived for their application to growing crops as the 
necessary basis of a knowledge of the course of assimila- 

• Read before the British Auociatioa (Sedion B), Ipswich 
Meeting, x8^. 



307 

tion, or more generally of the chemical life history of the 

Slant. It would be out of place to prejudice the enquiry 
y asking what are the useful resulu likely to follow from 
such investigations. It must be positively assumed that 
such results will certainly issue, and the work must be 
begun upon the convidion. 

On this view we have carried out for two years periodical 
investigation of barley crops growing upon the experi* 
mental plots of the Royal Agricultural Society at Wobum. 
We seleded two plots giving respedively the minimum 
and maximum yields of grain over a succession of years, 
viz. — 

Plot I. Permanently unmanured. 

Plot 6. Manured with 200 lbs. sulphate of potash, 100 
lbs. sulphate of soda, 100 lbs. sulphate of magnesia, 
3I cwts. superphosphate of lime, and 275 lbs. nitrate 
of soda* 

Our observations have been chiefly direded to the cellu 
lostc basis of the straw. It has been previously shown 
that the celluloses of cereals are widely differentiated from 
the normal type in the presence of a large proportion of 
furfural yielding constituents. While there are in part 
pentoses or pentosan groups, they consist in the main of 
oxidised derivatives of the hexoses ; and being the most 
charaderistic constituents of the permanent tissue it was 
clearly necessary to study the history of their assimilation 
as the basis of a systematic investigation of the history of 
the plant. 

We now give without further preliminary explanation 
the adual experimental numbers arrived at, as the scope 
of the investigation will be grasped from a mere inspedion 
of the tables of figures. 

In reference to the methods of observation, the results 
of which are embodied in the table, it is perhaps necessary 
to explain what is meant by ** permanent tissue.*' The 
plant may be regarded as made up of cellular and fibrous 
tissue, cell contents, and excreted produds. To eliminate 
the tatter and isolate the tissue the foUow.ng process has 
been employed : — 

I. After reducing the plant to <* cha0,*' exhaustive 6x- 
tradion with boiling alcohol, a. The residue is digested 



Barlby Samflbs.— Woburn. 



Date. 



Age 

of 
Crop. 



1894. May 7. 6 weeks | 
June 4* 10 weeks | 

July 10. 15 weeks I 

Aug. ai. 21 weeks | 

An« «* 22 weeks) 
Aug. 31. J j^y, j 

1895. May 15. 7 weeks j 

June z8. 12 weeks 1 

July 16. 16 weeks | 

Aug, 16. 20 weeks | 
22 weeks j 



Sept. 3. 



Plot j,-^ Minimum Yitld, 



4 days 



Plot. 



I 
6 

X 

6 

X 

6 

X 

6 

X 

6 

X 

6 
I 

6 

X 

6 

I 
6 

X 

6 



Total Dry Forforal. 
If alter, (a) Per ceot of 
Per cent. dry weight 



19-4 
176 

42*0 

32*9 
64*0 
64*6 
84*0 
864 

30*6 

17-8 
346 
33-4 
52-8 

54*4 
668 
65*0 
848 
86-3 



7*0 
70 

V 
8-x 

90 

zo*6 

irg 

I3'4 
127 

12*4 

6-6 

5-8 
80 
7-6 

X2*X 

xo'6 
9-2 
9-8 

xo-4 

IO'2 



Plot e^'-Maximum Yield. 



Parmanont 


Furfaral from 


TiMoe. 


Permanent Tiuoe. 


P.c. of dry 


(6) P.c. on (c) P.c. i 


weight. 


tissue. total 


53-4 


X27 6-8 


55-9 
529 


\ri IT 


58-5 


X3*4 7-8 


657 


9-8 6-4 


657 


12'5 8-2 


70*0 


14-5 lOI 


70-5 


i5'o io*6 


750 


165 X2-4 


78-4 


I5'X ii'8 


539 


xo-2 55 


567 


9-6 54 


38-2 


147 5-6 


44*5 


150 67 


55-6 


163 91 


46*2 


19* I 8-8 


^'i 


X70 8-3 


49-8 


191 9'4 


457 


17-6 8-0 


453 


17-3 7-8 



Ratio. 



X*03 J 
X-23J 
X'26: 
104 J 
1-40; 
1-30: 
x-i8: 
x'26: 
x*o2 : 
roSJ 

x*2o: 
x*07: 
x-42: 
XX4: 

1-33: 
x*2o : 
x»io: 
1*04 : 
i-3x: 
X'3o: 



NoTB.— The experimental results are expressed throughout upon the whole plant. For the agricultural bearings 
of the numbers it is necessary to further analyse the later numbers in reference to grain and straw. These 
points will be dealt with elsewhere. Our scheme of experiments for 1896 includes an examination into the 
effeds of preventing the formation of seed upon the permanent tissue of the stem. 



3o8 Percentage of Argon in Atmospheric and in Respired Air. 1^d2^:^S^'' 



four hoars at the ordinary temperature with dilute caustic 
soda (a'o per cent NaOH) and then washed, at first with 
cold, lastly with boiling water. 3. The residue is then 
digested with dilute hydrochloric acid (2 per cent HCl) in 
the cold, and then washed with cold, lastly with boiling 
water. 

The residue we take as approximately representing the 
tissue constituents. The process being one of hydrolysis 
is of empirical and somewhat arbitrary value. The value 
of the results will be estimated by their own internal evi- 
dence. If the definition *' permanent tissue *' be objeded 
to, it is easy to substitute the more corred description, 
which is **the residue from treatments by chlorophyll 
solvents and by hydrolytic agents, alkaline and acid, under 
carefully regulated conditions." The produd has served 
the purposes of these investigations, and will, we think, 
be seen to have the value of a " constant.*! 
We draw a number of conclusions from the result : — 
X. The conditions of soil nutrition are seen to have very 
little influence upon the composition of the plant. Com- 
parison of the numbers for the two plots taken in pairs 
show certain fluduations, it is true, and these are most 
marked at the most aAive period of growth, t./., at the 
flowering stage. Contrasted with this, the final condition 
of the tissue, f.#., at maturation, maybe taken as identical 
under conditions of minimum and maximum soil nutrition, 
as it may also at the initial stages of germination and 
early growth. The plant, in other words, is, as regards 
soil nutrition, constant or invariable in respeA of the 
relation of its produdls of assimilation. 

2. If we had had the seledion of extreme variations of 
' season we could not have chosen better than as between 

X894 and 1895. The influence upon the experimental 
numbers is extreme, more especially in regard to ** per- 
manent tissue." In the comparatively wet season of 1894 
there is a steady increase of permanent tissue ; in 1895 
the brilliant and continuous sunshine of the period up to 
and Including that of flowering determined a totally dif- 
ferent course. The proportion of easily hydrolysable 
carbohydrates shows ^ steady increase during the matu- 
ration period at the expenst of permanent tissue. The total 
dry matter t on the other hand, was influenced only in the 
stages up to and somewhat after the flowering period. 
Dehydration was for obvious reasons much more a&ive in 
1895, and the difference of condition in this resped in the 
case of plot 6 is quite remarkable. Certain industrial 
consequences follow from the history of the tissues 
(see foot note to table) : (x) the feeding value of 
straws grown in dry seasons is high : and (2), conversely, 
the paper-making value of such straws is low. More- 
over, while we may well assume a diminishing feeding 
value 6f the 1894 straw during the period of maturation, 
It would appear that in 1895 there is an adusl increase of 
feeding value of the mature straw over the straw taken at 
the flowering period. It is of course to be admitted that 
artificial hydrolysis is only a crude measure of digesti- 
bUity, and it would be important to confirm the conclusion 
by adual feeding experiments. That must be deferred to 
future opporttmities. 

3. The furfuroids have been diagnosed in various ways. 
Chiefly with the view of detetmining their distribution as 
between hydrolysable and non-hydrolysable (permanent 
tissue) constituents. In the early and late periods of 
growth the furfuroids are in the main of cellulosic cha- 
rader. The greatest divergence is seen to occur at the 
most adive period of growth, and here there is an accumu- 
lation of easily hydrolysable furfuroids. The maximum 
proportion was similar in the two seasons ; in both crops 
there is a gradual rise to and falling from the maximum ; 
in the 1895 ^^^P there was a marked change after cutting, 
and the change in the charader of the furfuroids was 
accompanied by a retrograde change in the '* permanent 
tissue." This retrograde movement, it will be noted, was 
continuous from the flowering period and in exad contrast 
to the history of assimilation in 1894. 

A fair interpretation of the results appears to be this : 



the furfuroids are by no means excreted produds, but 
available for assimilation, and they are in fad continuously 
assiniilated to permanent tissue (cellulose). Owing to the 
deficient moisture in the period to July z6th the building 
up of new matter (growth) was interfered with, and the 
'* permanent tissue" was put under contribution for 
nutrient material which, under ordinarv conditions, would 
have been drawn from cell-contents and not from tissue. 

In the month July z6ih to August i6th there is, in fad, 
a notable falling off in the total quantity (proportion) of 
furfuroids, which confirms the view that these constitu* 
ents were put under contribution seledively, to the general 
needs of the plant. 

Viewed broadly and generally these investigations show 
how very different are the results of physiological study of 
the history of crops from those of investigations of soil 
nutrition. The essential charaderistics of the plant are 
maintained independently of the fadors of soil nutrition. 
The comparative study of the two crops proves this con- 
clusively. 

In our opinion systematic investigation of the adual 
physiological, i.#., chemical, constants of the plant, will 
lead to results of which at present it is impossible to pre- 
did the import. 

Take it that we had been able to make a complete 
proximate resolution of the straw substance from time to 
time, instead of confining ourselves to one group of the 
carbohydrate constituents : it is easy to see that much 
wider and more positive conclusions could have been 
drawn. 

But private enterprise has its obvious limits, and ex* 
haustive investigations of this charader can only be tmder- 
taken by institutions fully equipped and supported by 
adequate funds. 

Vve hope this preliminary contribution will serve as an 
indication of the results likely to follow from the syste- 
matic work of such an institution. 



ON THE 

PERCENTAGE OF ARGON IN ATMOSPHERIC 
AND IN RESPIRED AIR.* 

By ALEXANDER KELLAS. B.Sc., 

Assistant in the Chemical Department of University 

College, London. 

Although blood invariably contains a small amount of 
dissolved nitrogen, it appears that with animals no absorp- 
tion of that gas takes place than what is due to its solu- 
bility in the serum of the blood. Nor is nitrogen eliminated 
from the system in the elementary state. 

At Professor Ramsay's suggestion, experiments have 
been made on the comparative amount of argon in or- 
dinary air, and in air which had been frequently breathed, 
with the view of ascertaining whether, if the proportion of 
oxygen and carbon dioxide in air be very much altered, 
argon would either enter into, or be expelled from the 
respiratory system. The result of the experiments to be 
described is to show that the proportion of argon to nitro- 
gen remains nearly normal, even when the air has been 
greatly altered in composition by respiration. 

I. Percentage of Argon in A tmospheric Air, — A mercury 
reservoir, the capacity of which was accurately determined 
by weighing with water, held 555*2 c.c. The upper end 
was fitted with a three-way tap, sealed on to the glass. 
Through this tap was admitted air, purified by passage 
over soda-lime and phosphoric anhydride, to remove 
water-vapour and carbonic anhydride. This reservoir 
was jacketted with water of known temperature, so that 
the volume of the air could be measured with great exad* 
ness. The other branch of the three-way tap led -to a 
tube filled with copper, in order to absorb oxygen ; one 

* A Paper read before the Royal Sodtty. 



Dec. Z7, 1895. f 



Argon and Helium in the Gases Jrom Sulphurous Springs. 309 



containing copper oxide to desuoy any organic matter 
which might have been present, and one filled with roag- 
nesiaro turnings to absorb nitrogen ; these tubes were 
kept red hot. Other tubes were filled with soda-lime and 
phosphoric anhydride, so as to remove water and carbon 
dioxide, which might have been produced. The air was 
circulated over these absorbents until little but argon 
was left. The gas-holder was filled three times at i8*8° 
C, and 752*1 m.m. pressure. After absorption had nearly 
ceased, the remaining gas was pumped out of the tubes, 
mixed with oxygen, and sparked for many hours in pre* 
sence of caustic soda, to remove the last traces of nitro- 
gen. The residue, after absorption of oxygen with potas- 
sium pyrogallate, measured 15*91 c.c. at 21 V C, and 
754*5 m.m. pressure. 

Reducing both volumes to standard temperature and 
pressure, it appears that— 

Z542'o c.c. of air yielded 14*45 c.c. of argon, or 
xoo'o c.c. of air contain 0*937 c*c* ^^ argon. 
Calculating the percentage in atmospheric nitrogen, we 
have — 
xoo c.c. of mixed atmospheric nitrogen and argon con- 
tain 1*186 c.c. 

Owing to the avoidance of the presence of water during 
these experiments, they are probably more accurate than 
the original experiments of Lord Rayleigh and Professor 
Ramsay. They found ("Argon," Phil, Trans,, 1895, A, 
pp. 221 and 214) 1*04 and 1*03 in two experiments in 
which the nitrogen was removed by sparking with oxygen 
in presence of dilute caustic soda; and i*ix when the 
nitrogen was removed by means of magnesium. 

Owing to the vacation, it has not been possible to put 
this result on record before now. And Th. Schloesing, 
jun., has recently published Comptes Rendus, vol. cxxi., p. 
605) the results of a series of estimations in which the 
percentage of argon in atmospheric nitrogen was found to 
be i*x8o to 1*185, or as a mean x*x83 per cent, a number 
almost identical with that just recorded. M. Schlcesing 
has re-calculated the ratio which ought to subsist between 
the densities of atmospheric and *' chemical '' nitrogen on 
the basis of his determinations ; but in doing so, he has 
made use of the value 1*2505 grm. as the weight of one 
litre of the latter, instead of 1*2511 {Phil, Trans., 1895, A* 
p. 189). Moreover, he has assumed Regnault's value, now 
superseded, for the weight of i litre of hydrogen, viz. , 
0*0896 grm., instead of that given by the more recent 
determinations, 0*0899 (Phil, Trans., 1895, A, p. 292). 
These are not serious errors, but it is more satisfaAory to 
calculate the corre^ number. The question is :— If the 
weight of a litre of pure nitrogen is X'25xx grm., and of 
argon 1*7818 grm., and if atmospheric nitrogen contain 
I 185 per cent of argon, what should be the weight of a 
litre of the latter? The answer is 1*2574. Lord Rayleigh 
found the number x*2572, one almost exa&ly identical. 

For material for the second part of this research, I have 
to express my thanks to Dr. Marcet, F.R.S., and his 
assistant, Mr. Floris. The air was analysed before 
having been breathed, and had the normal composition : — 

Nitrogen and argon. • •• 79*02 per cent 

Oxygen 20*93 » 

Carbon dioxide 0*05 ,» 



The air was breathed over and over again by Mr. Floris, 
until after ten minutes* respiration its composition had 
become : — 

Nitrogen and argon.. ,. 80*96 per cent 

Oxygen 5-40 »i 

Carbon dioxide X3'^4 ft 



An estimation of the argon was carried out in precisely 
the same manner as before, on x 297*8 c.c. of breathed air. 



measured at X7'2° C. and 759 m.m. pressure. But the 
air was breathed over water, the requisite change of 
volume on respiration having been secured by breathing 
into one of Dr. Marcet's counterpoised gas-holders. The 
argon found measured at 177° C. and 752*3 m.m. pressure 
12*85 c.c. These numbers correded give — 
1 196 c.c. of breathed air yielded xi'72 c.c. of argon. 
100 c.c. „ „ 0980 c.c. of argon. 

Calculating the percentage on the nitrogen, we have :— 
xoo c.c. of nitrogen and argon of breathed air contains 

1*210 c.c. 
This percentage is larger than that in normal air. One 
of two suppositions may be made: — Either the increased 
amount is due to the air having been confined over water 
during breathing, or argon is given off from blood in 
greater amount than it is absorbed, when the composition 
of the air in the lungs is so much altered ; the former 
appears the more probable supposition. In any case the 
difference is not great ; and it would appear that argon, 
like free nitrogen, plays no important part in the animal 
economy, save as a diluent. 



ON THE 

ORIGIN OF THE ARGON AND THE HELIUM 
IN THE GASES ESCAPING FROM CERTAIN 
SULPHUROUS SPRINGS. 
By L. TROOST and L. OUVRARO. 

In his communication concerning the presence of argon 
and helium in the gases liberated from the sulphurous 
springs of Cauterets, Dr. Bouchard has indicated the 
importance of examining, from the same point of view, 
the gases in solution in waters which flow or stand 
on the surface of the ground. 

We might, in fad, put forward the idea that the gases 
liberated by the sulphur waters are derived exclusively 
from the atmosphere. The solubility of argon might 
cause us to admit that the gases carried down by the 
waters from the surface into the depths of the earth, re* 
ascend with the same waters which have been rendered 
alkaline by a sulphide. 

To throw a light on this question we have examined 
the gases from the water of the Seine (supplying the 
laboratories of the Sorbonne), and from sea- water, col* 
le^ed at high tide on the shore of the ocean. We have 
there sought for helium, independently of argon, which 
we were certain to find, since it is more soluble than ni- 
trogen, which always exists in waters in contad with 
the atmosphere. 

These gases, colleAed with the ordinary precautions 
and freed from carbonic acid by means of potassa, were 
treated in two different manner^. The nitrogen was 
removed either by causing it to be absorbed by magne- 
sium heated to redness, or by combining it with oxygen 
under the influence of eledric sparks in presence of 
potassa. 

This latter procedure is more tedious but more trust- 
worthy, since the gas, constantly enclosed in the same 
glass tube over mercury, and without any transferences, 
is preserved from any mixture, even with very minute 
quantities of atmospheric air. 

The gaseous residue obtained was dried over melted 
potassa and placed in connedtion, as in our former experi- 
ments {CompUs Rendus, cxxi., p. 394), with a Pliicker 
tube with eledrodes of raagnesmm in which a vacuum 
had been made by means of the mercurial pump. 

The tube was repeatedly swept out with the gases in 
question, the vacuum being made each time anew. Then, 
after a final introduAion of the gases, the efHuve was 
caused to pass between the magnesium eledrodes. 



310 



Manufacture and Commercial Separation of Glucinutn. 



I Cbimical Niwi, 
I Dec ^« 1895. 



The speAroBCope from the first constantly indicated 
the presence of traces of nitrogen, but on prolonging the 
experiment they disappeared. We were then able to de- 
cide that the spedira furnished by the gases from the wells 
of Cauterets were strikingly different from those afforded 
by the gases extraded from the water of the Seine and 
from sea-water. 

These Utter give the spedlrum of argon, and merely 
traces of the spe^rum of helium scarcely perceptible and 
often doubtful, whilst the gases colleded at the well-head 
of the Bailli^re, or extradled by boiling the water from the 
same spring, give very distinAly the charaderistic rays 
of argon and those of helium, and that the gases colle^ed 
at the well-heads of the sources of the Bois give espe- 
cially the charadkeristic rays of helium. 

The helium contained in the gases liberated from the 
mineral springs of Cauterets does not consequently seem 
to us to be due to the atmosphere. The gas is derived 
probably from the rocks in the strata which these mineral 
waters have traversed. 

The presence of helium lately proved in a certain 
number of minerals, such as cllveite, brdggerite, orangite, 
monazite, &c., renders* this conclusion at least possible, 
to that, outside of any medical consideration, the study 
of the gases evolved by mineral waters would derive an 
especial interest from the fadk that these gases may 
supply us with new information concerning the elements 
of the rocks which these waters encounter in the strata 
whence they issue. 

With reference to the above communication, Dr. 
Bouchard added the following observations :— 

I have stated in the paper to which M. Troost refers 
that, in all probability, the therapeutic adivity of the 
mineral waters in which I showed the presence of argon 
and helium is not due to these gases. I added, that if 
these gases were present in the waters which flow or 
stand on the surface of the earth, the question would be 
decided, since these (surface) waters have not the thera- 
peutic value of the mineral springs in question. But if 
argon and helium are inert, it may not be the same with 
mineral substances with which they are in combination. 

It is established, by the communication of M. Troost, 
that helium at least is derived from the depths of the 
waters. Among the mineral compounds of helium there 
may be some wnich, even in minimal cases, may exert a 
physiological a6ion upon the organism. On this hypo- 
thesis the effeA would be due not to helium, but to the 
metal with which it was combined, always supposing 
that such a compound or its derivatives were sufficiently 
soluble.— Com^</j Rendus, cxxi., p. 798. 



ON THE 

PRESENCE OF ARGON AND OF HELIUM 

IN A SOURCE OF NATURAL NITROGEN. 

By CH. MOUREU. 

Quite recently M. Bouchard has po'nted out the presence 
of helium in the gases of the springs of Bois (Cauterets), 
and that of helium and argon in the gases of the Railli^re. 
Whilst studying the same subjedt, MM. Troost and 
Ouvrard have discovered an important property of argon 
and helium— that of being absorbed by magnesium at a 
very high temperature. 

I have Just recognised the same two elements together 
in another natural gas which escapes abundantly in large 
bubbles from the spring of Maizieres (Cdte d*Or). The 
water of Maizieres is a lithium water containing a little 
calcium sulphate, and it has at the source the temperature 
of +12^ Thanks to the courtesy of M. Communaux, 
the direAor of the company, I have had at my disposal 
several litres of the gas. The specimens had been col- 
leAed with all the usual precautions, so as to avoid cen- 



tal with air, which would necessarily have introduced 
argon. 

The analysis over mercury showed me at once that the 
gas contained a small proportion of oxygen (about a per 
cent), the residue presenting all the negative charaAers 
of nitrogen. 

To deted argon and helium I had recourse to the kind- 
ness of M. Deslandres, who has kindly undertaken these 
delicate experiments. After absorbing the nitrogen by 
lithium at a dull red heat, the gaseous residue was intro- 
duced into Pliicker tubes at a low pressure, and, on being 
submitted to the effluve, it gave the charaderistic rays of 
argon and of helium. 

We may add that the proportion of these gases hu 
been found rather considerable ; the volume of the gaseous 
residue not absorbed by lithium is between one-tenth and 
one-fifteenth of the total volume. 

Although the analysis has not been carried further, it 
seemed to me interesting to communicate these results to 
the Academy, not only on account of the presence of 
argon and of helium in a source of natural gas, but be- 
cause of the relatively high proportion of these two 
elements in the gaseous mixture. — CompUs Rindus^cxxu 
p. 819. 



THE MANUFACTURE AND COMMERCIAL 

SEPARATION OF GLUCINUM. 

By H. N. WARREN, Research Analyst. 

Probably one of the most eccentric metallargical orders 
of the times has been recently executed at the Research 
Laboratory, in the method of manufaAuring glucinum for 
jewellery purposes. In order to ensure a large percentage 
of glucinum in the ore seleAed, six pounds of emerald- 
dust and stones of dull water were specially imported 
from various patts of the world ; ground to a fine powder, 
and the finer qualities separated by lixiviation and re- 
grinding. The powder so prepared was next thoroughly 
incorporated with four times its weight of sodic carbonate, 
and finally fused for three hours at the highest tempera* 
ture of a powerful blast-furnace, and afterwards cast into 
square plates for further treatment. The second opera- 
tion consisted in dissolving the melt thus formed as near 
as possible by the aid of supersaturated steam; and 
further effeding a complete decomposition by the iotro- 
dudlion of an excess of hydrochloric acid, and evaporating 
it to dryness in order to render insoluble the silica present. 

The siliceous residue having been washed and squeezed 
in a suitable press, was now rejeded ; the washings, to- 
gether with the filtrate, being rendered alkaline by means 
of an excess o( sodium carbonate, the solution having 
previously been freed from iron and chromium by 
acetates, in accordance with the usual separation of these 
metals. 

The precipitate obtained by the introduaion of the 
sodium carbonate was now thrown into a comroodions 
glass receptacle, and heated with an excess of gaseous 
sulphurous acid, in which both the alumina and glucina 
dissolve. The solution thus obtained, upon being raised 
to ebullition, precipitates the alumina in a granular form, 
in place of the tedious gelatinous deposit obtained by the 
old ammonia process, which in the former case is washed 
with the greatest of ease. To the second filtrate thus 
obtained was added an excess of ammonium carbonate, 
and the solution well boiled ; the glucinum carbonate 
being thus completely precipitated, also in a granular 
form, and admitting of being readily washed. The pre- 
cipitate thus obtained being further intimately mixed with 
an excess of lamp-black and ignited out of contad^ with 
the atmosphere, the mass thus obtained being afterwards 
converted into bromide by aAing upon it with .bromine* 
vapour at a full red heat in clay retorts. The bromide 
distils over, and is readily reduced to the metallic form 



C«bmicalNbws,\ 
Dec. 27. »»95. I 



Chemical Researches and Spectroscopic Studies. 



311 



by decompoftiog the tame with an eleAric current of 12 
volts 8 amperes. 

The metal thus obtained, having been worked into 
articles, is now in the possession of the Ameer of 
Afghanistan. 

Liverpool Research Laboratory, 
18, Albion Street, Evertoo, Liverpool. 



CHEMICAL RESEARCHES AND SPECTROSCOPIC 

STUDIES OF VARIOUS ELEMENTS. 

By JEAN SERVAIS STAS. 

(Continaed from p. 304). 

Pftparation of Ptrehlorate of Potassium, 
The chlorate of potassium, the preparation of which I 
bave described above, is used for the pteparation of pure 
perchlorate and chloride of potassium. 

As I said above, my objed^ was to decompose the 
chlorate in such a way as to make on, the one hand, the 
greatest possible quantity of perchlorate, and, on the other 
hand, a quantityof perchlorate just sufficient to make the 
chloride required to estimate its molecular relation to 
silver. 

M. Marignac has published in his works the methods 
of obtaining this result, and to them I have nothing to 
add. I will confine myself to saying that I effeaed the 
reduAion of chlorate into perchlorate and chloride in a 
large platinum retort, tht inside of which was first polishid, 
the neck on the lid of which entered into a large tube 50 
cm. long, containing a roll of asbestos packing, as I shall 
describe farther on in a special memorandum. 

The retort rested on an earthenware tripod, which was 
strengthened by iron wires ; it was heated by means of a 
singli Bunsen flame through two pieces of wire gauze, to 
distribute the heat evenly, which is indisptnsablt, 

I redaced it in four operations ; two being for the pur- 
pose of getting from about 50 to 60 per cent of perchlorate 
of potassium, and two for getting 10 per cent only of this 
salt, entirely decomposing the chlorate experimented on. 

The first operation was done at the lowest possible tem- 
perature, and occupied as much as twenty-six hours. I 
found that by keeping the fused chlorate at the tempera- 
ture at which oxyeen is slowly disengaged, and the vessel 
makes a noise or decrepitation similar to that heard when 
fresh water is heated beyond So** in a metallic vessel, dis- 
sociation took place with an evolution of heat ; the fused 
mass was eventually agiuted, and finally became pasty. 
When it reached this state, all the chlorate was destroyed, 
and the maximum of perchlorate was obtained. The 
•eparation was effeded without liberaiing a trace of 
chlorine, but the oxygen disengaged smelt of oxom. If, 
during the dissociation, which is exothermic, one does 
not sufficiently reduce the supply of heat, the mass heats 
itself until the platinum vessel becomes incandescent, as 
I have often found when reducing chlorate in a covered 
platinum crucible. In this case, not only does the 
chlorate decompose without forming perchlorate, but the 
greater part of the salt already formed decomposes, and 
leaves chloride only. This decomposition is, therefore, 
slightly explosive, and may, if one does not take care, 
cause the loss of part of the salt submitted to the adion 
of heat. Whether the separation be made slowly or 
quichly, the chloride and perchlorate formed are white ; 
there is no evolution of free chlorine, the chloride is 
nentrml to litmus paper, and the platinum vessel is not 
altered at all. 

I took the greatest pains to satisfy myself of these faas, 
M mentioned in the special memorandum on this subjed, 
because, daring my previous work, when working on 
siliceous chlorate, I always noticed a sensible evolution 
of chlorine, a very slight attack on the platinum, and tne 
presence of this metal in the form of chlorbplatinate in 
the chloride made. 



I then turned my attention to obtaining the greatest 
possible quantity of perchlorate. 

In two operations successfully carried on for this pur- 
pose, I warmed the chlorate to a temperature just suffi- 
cient to induce a very weak evolution of oxygen, and I 
kept the temperature constant from 8 a.m. to 6 p.m. for 
two days and a half consecutively, the length of time 
necessary to reduce the mass to a pasty condition, and 
obtain at the constant temperature the cessation of the 
evolution of oxygen, and the absence of very light lames 
in the large long tube into which the neck of the retort lid 
entered. 

To procure the perchlorate necessary for producing the 
amount of chloride required for estimating its molecnlar 
relation to silver, I noted the time requir^ for the total 
decomposition, at tht lowest ^ssibU conttant temperaturif 
of the perchlorate, effeAed by working on a mixture of 
almost equal weights of chloride and this salt, made from 
about 100 grms. of chlorate. 

After oxygen ceased to be evolved at constant tempera- 
ture— which is coincident with the complete dissociation 
of the chlorate, and the formation of the greatest amount 
of perchlorate compatible with this readion— I gently 
raised the temperature until I caused once more a slight 
evolution of oxygen, and the appearance of the saline 
fume ; I then kept the temperature constant for six hoort. 
I found, by a preliminary trial, that at least twelve hours 
were required to decompose the whole of the perchlorate 
in the mixture at this temperature. 

Separation of Pirchlorate and Chloride of Potassium, 

I effeded this separation by dissolving the salt in pore 
cold water and using then just enough water to make a 
saturated chloride solution. Diredly the chloride was 
dissolved, which was done in enclosed and purified air, 
the liquor coloured a Bunsen flame blue, though a very 
much lighter tint than chlorate gives. The solution waa 
drawn off each time, and, although quite clear, it was 
poured into a filter-paper which had been most carefully 
washed with dilute hydrofluoric and hydrochloric acids 
and pure water, arranged in a platinum funnel covered by 
a belljar, the surface of which, as well as the glass plate 
on which it stood, was wetted. The solution was evapo* 
rated nearly to dryness in a loosely covered platinum dish, 
under a bell-jar filled with air saturated with moistivei 
so as to prevent, as far as possible, the saturated solution 
from rising up to the edge of the dish and depositing solid 
chloride on it. 

The mother - liquor from chloride, crystallised by 
cooling, was neutral to litmus paper; it was drawn off 
into a platinum dish, and again evaporated down to satu- 
ration point under a damp bell-jar. The chloride 
deposited by cooling was separated from the mother- 
liquor, and this was evaporated to dryness under a damp 
bell-jar, carefully separating the chloride on the edge of 
the dish. By working thus, I obtained, in decreasing 
quantities, three samples of chloride made at the same 
time as the perchlorate. 

I have most carefully examined the spedrum of each 
of these three samples, and found them to be identical. 

I used the second sample to find out what residue it 
contained, and found none. 

I shall describe further on how I treated each of these 
chlorides when estimating their molecular relation to pure 
silver. 

Without removing the crystalline powdered perchlorate 
from the retort, I crystallised it three times, changing 
the mother-liquor and the water with which it was par- 
tially washed each time ; they yielded a salt which 
coloured a hydrogen flame pale blue, and gave a potassium 
spedrum without the sodium line, similar to that of the 
chloride made at the same time as the perchlorate. 

The boiling perchlorate solution, when put into a 
Bunsen flame on the end of a fine platinum wire spiral, 
coloured it a very pale blue. Spectrum analysis did not 
show the sodium line. This experiment was repeated 



3i« 



Chemical Researches and Spectroscopic Studies. 



I CRimcAi, >>wi. 



Dec 27, 1895* 



several timet— whenever the state of the air allowed it — 
and always with the tame result. 

I have plunged into thit boiling perchlorate tolution 
several fine platinum wire spirals, coated with spongy 
platinum, previously heated to redness. I have left them 
under a large bell-jar filled with the air of the room 
where I was workmg, for the purpose of showing to 
several people that pure perchlorate coloured a flame blue 
and had no sodium line in its spedrum. I found that 
after from twenty-five to thirty minutes the crystallised 
perchlorate on the platinum spiral had absorbed enough 
sodium from the air to thow the sodium line, very faintly 
it it true, but ttill unmittakably. In fad, from the 
moment I left the spirals under the bell-jar, the air of the 
room, which took the place of the air in the bell-jar by 
diffusion, became charged with sodium owing to the 
draughts in the room. One must be well acquainted with 
all the difficulties met with in a research of this nature in 
order to get a true idea of them. I express myself more 
fully on this subjedk in my ** Study of Atmospheric Air," 
to which I beg to refer my readers. 

The perchlorate of potassium which had been crystal- 
lised three separate times in a platinum retort covered by 
its domed top, and filled with enclosed and purified air, 
was reduced to chloride in it. This decomposition, when 
carefully done, is not difficult ; tht separation into chloride 
and oxygen was effected without evolving any chlorine, and 
the chloride was neutral to litmus paper, 

I treated the chloride made from perchlorate in exadly 
the same way as chloride made at the same time as this 
salt ; that it to tay, I put it into just sufficient cold water to 
dissolve it. The solution was passed through carefully 
cleansed filter-papers without leaving any residue after 
the filter was washed. The clear liquid was evaporated 
to saturation at xooS in a platinum dish loosely covered 
with a sheet of the same metal, and under a damp bell-jar. 
The mother- liquor, when poured off from the crystallised 
chloride, was in its turn evaporated to saturation at zoo°; 
and, finally, this last mother-liquor was dried in a loosely 
covered platinum dish under a damp bell-jar. 

I have thus obtained three samples of chloride made from 
perchlorate under conditions which yielded by dissocia- 
tion of chlorate, on the one hand, the greatest possible 
amount of this salt and the least possible of chloride ; 
and on the other hand, one-sixth part, at the most, of per- 
chlorate, and the rest chloride. 

The second sample of chloride made from perchlorate 
was used for showing the spedrum of the metal in it. I 
found the f pedrum to be identical with that of chloride 
made at the »ame time as the perchlorate. 

Lastly, I have worked on three samples, in decreasing 
quantities, of chloride made by crystallisation during the 
course of an experiment undertaken for the purpose of 
studying the conditions to be fulfilled in order to partly 
decompose the perchlorate formed by the complete disso- 
ciation of the chlorate. 

All these chlorides, when dissolved in water, gave clear 
solutions, neutral to litmus paper ; nevertheless, when 
heated in a platinum dish with pure chloride of ammo- 
nium, with an acid reaction, to a sufficiently high tem- 
perature to evolve white fumes, they gave off vapour which 
turned red litmus paper distindly blue. 

Fearing that traces of sulphate of potassium were pre* 
sent in these chlorides, I submitted them all to special 
treatment. 

Treatment of Chloride oj Potassium by Pure Chloride 
of Ammonium, 

All the samples of chloride of potassium mentioned 
above were melted in pure sal-ammoniac, which was pre- 
pared by passing ammonia and hydrochloric acid gases 
through pure water in a large platinum apparatus, sup* 

g lying always an excess of ammonia. The gases were 
rought through purified rubber tubes, weighted with 
platinum to keep the open end down. 
The solution, which smelt strongly of ammonia, was 



evaporated to saturation in the platinum apparatus. After 
cooling it quickly, the mother- liquor was poured off and 
entirely changed. 

The chloride of ammonium left in the apparatus gave no 
sodic reactions^ proof that, under the above-mentioned 
conditions, neither the ammonia nor hydrochloric acid 
gas brought any trace of sodium. I emphasize this point, 
because the use of this sal-ammoniac to reduce oxides 
free from sodium into chlorides always forms compounds 
which eive conclusive evidence of the presence of sodium 
when these chlorides are hygroscopic, I shall return to 
this subjed when describing my researches on chloride of 
calcium. 

Having found that sal-ammoniac, when separated, was 
quickly contaminated by sodium from the air, I sublimed 
part of it in a platinum retort in an atmosphere of dry am- 
monia. In order to do this, I put the platinum retort con- 
taining the salt to be sublimed on an iron plate in a gas- 
stove that I have described and illustrated on page 553 
of my '* New Researches on the Laws of Chemical Pro- 
portions,** taking care to leave the upper two-thirds of the 
retort outcide the stove, and to shield this part from the 
gases at the temperature of the volatilisation of sal- 
ammoniac, by means of a second iron plate. 

Having ground the neck of the retort lid, as far as pot* 
sible into a long tube, I passed a tube for the supply of 
dry ammonia, which was admitted through a cork at the 
other end of it, through it, as far as the entrance to the 
dome of the lid. 

The air in the retort being entirely replaced by dry am- 
monia, I regulated the heat imparted to the gases by the 
combustion of coal-gas in the following manner, so as to 
sublime the sal-ammoniac slowly :~I put an open tube 
containing sal-ammoniac, with the upper end protruding 
from the stove, in the bottom of the retort, to ad at a 
thermometer. When, by reason of the high temperature 
of the gas, I saw the sal-ammoniac crystallising slowly in 
rings on the upper part of the open tube, I kept the 
supply of coal-gas burning in the stove constant for five 
hours by means of a regulator. Five hours were adually 
required for slowly subliming about 150 grms. of sal- 
ammoniac, the quantity on which I was working. 

I have gone into these minute details because I have 
been asked to do so by certain chemists who, having 
wished to obtain some sal • ammoniac sublimed in 
platinum, have failed to do so, though they followed the 
diredions given on page 473 of my " New Researches on 
the Laws of Chemical Proportions." 

Sal-ammoniac volatilised as I have just described, con- 
denses in the same retort in the form of a very thiek^ 
transparent t colourless, and elastic ring, which becomes 
detached after cooling for some time, becoming entirely 
opaque. The domed top is filled with powdery sal- 
ammoniac, smelling strongly of ammonia, and rapidly 
taking up sodium from the air. 

Sublimed chloride of ammonium gives no sodic charac- 
teristics to flames ; but when kept under a bell-jar 
shielded from atmospheric dust, it slowly condenses 
sodium compounds on its surface, as all solids do under 
similar conditions. 

Coming back to the treatment of chloride of potassium 
by chloride of ammonium. 

To fuse chloride of potassium, I put in the bottom of a 
large platinum crucible, quite free from iron,* first of all 
a layer of alkaline chloride in powdered crystals, then a 

* A crucible made ol pare platinum it deprived of tbe iron intro- 
duced into it by welding, by treating it, at a low red heat, with 
chloride of ammonium. This treatment ia continued until one gets 
a colourless button of melted chloride on fusing a mixture of pure 
alkaline chloride and sal-ammoniac. So long at the platinum retaiM 
traces of iron, an alkaline chloride melted in it with tal-anunoniac 
forma a red or pink mats, and looses the ferric oxide when ditaolved 
in water. Alkaline chlorides dissolve ferric oxide when melted, and 
loose it when cooled. It it only necessary to dissolve melted 
ferriferout chlorides in cold water to obtain, on filtering the aolntioa 
and evaporating the liquid, a perfedtiy white saline mass, which one 
can melt in a pure platinum crucible with sal-ammoniac, and foriB, 
on solidification, an absolutely COlourlett button. 



Cbmiical Niwtt I 
D«c. S7. r8^. I 



Researches on the T&rpenes. 



313 



piece of sal-ammoniac, and finally I filled the crucible 
with melted chloride mixed with small pieces of sal- 
ammoniac. 

After patting the lid on the crucible, I warmed it 
slowly to a dull red heat, then 1 kept it at least fifteen 
miniitet at a bright red heat, until, on lifting the lid, the 
gaks bubbles seen round the edge of a crucible containing 
^ ao alkaline chloride melted with sal-ammoniac, had en- 
tirely disappeared. I quickly poured the chloride into a 
receotly heated and cooled platinum dish. If the opera- 
tion has been properly conduced— that is to say, if the 
chloride has been kept fused at a high temperature for a 
sii£Scient length of time — the button is eolourltss^ limpid^ 
amd trantfanntt and contains no gas bubbles. 

When I found bubbles present, a sign of the existence 
of sal-ammoniac or of the produds of decomposition,/ 
r^-mglted tkt button in a double crucible of pure platinum, 
and I then turned the melted chloride into a platinum 
dish. 

The buttons, when cold, were broken in an agate 
nortar, and the pieces, the edges of which had become 
milky, were put into flasks with ground glass stoppers. 

Since they were made from chlorates and perchlorates 
which left no trace of solid residue on volatilisation, I 
( natarally dispensed with testing the chlorides afresh. The 
▼ery great care that I took during the work to prevent 
siliceous and sodic atmospheric dust from falling into the 
aalt is a suflScient guarantee for its purity. 

(To be continacd). 



PROCEEDINGS OF SOCIETIES. 

CHEMICAL SOCIETY. 
Ordinary Metting, Decimbtr 5M, 2895. 

Mr. A. O. ViKMON Harcourt, President, in the Chair. 

Cbktificatbs were read for the first time in favour of 
Messrs. John Allan, 242, Moss Lane East, Manchester ; 
Herbert Lister Bowman, 13. Sheffield Gardens, Kensing- 
ton, W. : James Kerry Burbridge, Moor's Lea, Winchmore 
Hill ; Frank Dixon, 73, King Edward Road, South Hack. 
oey, N.E. ; Joseph Edward Morrison, Montreal ; Harold 
Roatfon,70, Davenport Street, Bolton ; Peter 6. Scotland, 
30, Stirling Street, Airdrie, N.B. ; Aitken Migget Simp- 
son, 4, Kitto Road, St. Catherine's Park, S.E. ; Henry G. 
Smith, Technological Museum, Sydney, N.S.W. 

Mr. Otto Hshnbr called the attention of the Society 
to what he regarded as unprofessional conduA on the part 
of a Fellow 01 the Society whose name appeared on the 
certificates of certain candidates who were to be ballotted 
for that evening. 

Professor Armstrong then moved, and Mr. Groves 
seconded, that the Council be requested to consider this 
caae. Professor Tildbn having spoken in support of the 
motion, it was put to the meeting and carried. 

The following were duly eleded Fellows of the 
Society >— George Percy Bailey. B.A., The Earl of Berke- 
ley, Anbnr Jenner Chapman, Wm. Chattaway, George 
Bertram Cockburo, B.A., Charles Crocker, Gurney Cuth- 
befftaon, William Dixon, Edward Henrv Farr, Charles 
Jamea Fauvel, Patrick Joseph D. Fielding, Jervis E. 
roakes, Stanley Fox, James Gardner, Edward Graham, 
B.Sc., Edward Henry Grossmann, The Rev. Henry Arthur 
Hall, M.A., Edgar Septimus Hanes, C. E. Harriton, B. A., 
Jamea Henderson, B.Sc, Thomas Hawkins, Percy 
Hertot, Frederick Arthur Hillard, B.A., Arthur Edward 
Holme, M.A. (Oxon.), Alfred James, Frederick Edward 

Johnson, William Oakes Kibble, Leonard P. Kinnicut, 
amea McCreath, David James Morgan, William Henry 
Pcfinington, Martin Priest, W. T. B. Ridge, William , 



Round, William Augustus Rugginz, Clarence Arthur 
Seyler, B.Sc, Mathew Smith, B.A., Frank R Stephens, 
George Stone, W. J. Tibbals, John Williams, B.A., 
Thomas Rowland Wingfield, and Harold E. Wright. 

Of the following papers those marked * were read — 

•141. •* Researchis on the Ter perns, VI. Products of 
the Oxidation of Camhhene : Camhhoic Add ahd its D$» 
rivatives," By J. E. Marsh and J. A. Gardnbr. 

In this paper some of the oxidation produAs of cam* 
phene are described, among them being camphoic acid, 
CX0H14O6, as chief produd, camphoric acid in small quan- 
tity, terephthalic acid, and succinic acid. 

From camphoric acid were obtained :—Anhydrocam« 
phoic acid, C10H14O5; cis- and trant-camphopyric acids, 
C9H14O4; camphopyric chloride, CgHijClsOa; chloro* 
camphopyric chloride, CgHnCljOa; chlorocamphopyric 
anhydride, C9HX4CIO3 ; camphopyranilic acid,— 

CgHxaOalNHCeHs); 
and salts of camphoic and camphopytic acids. With 
camphopyric acid is compared camphoric acid in reaped of 
their both existing as cis- and trana-isomers, and also as 
regards the acid chloride, chloroacid chloride, and chloro- 
anhydride, producible from both camphoric and campho- 
pyric acids. 

The redudion of camphopyric acid to hexahydrometa* 
xylene has also been accomplished, while the constitution 
of camphene is discussed from the general analogy of 
camphoric and camphopyric acids, from the probability 
of their both containing a hexamethylene nucleus, from 
the fad of the produdion of both acids from camphene 
and from the probability that neither camphoic acid nor 
camphopyric acid is producible from camphoric acid. 
Discussion. 

Professor Armstrong inquired whether Mr. Marsh 
could give any further information as to the isomeric 
bromocamphor described by him on a previous occasion, 
since he (Profesor Armstrong) had not been able to con- 
firm Mr. Marsh's results. 

If a molecular proportion of bromine be added to Cam- 
phor heated on the water-bath, using i or 2 per cent in 
excess, so as to ensure the absence of camphor, an almost 
theoretical yield of bromocamphor (m. p. 7^°) is obtained. 
If, to purify the produd, it be dissolved in hot alcohol, 
the greater part of the bromocamphor at once crystallises 
out as the solution cools, and if tne small amount of oily' 
residue obtained from the mother-liquor^a mixture of 
mono- and dibromocamphor — be digested with alcoholic 
potash, so as to reduce the dibromo*compound, this also 
is conveited into well-crystallised bromocamphor. 

According to Marsh [Trans, Chem, Soc, x8go, 828), if 
camphor be brominated in presence of sJcohol, almost 
half the produd consists of an isomeric bromocamphor 
of ill-defined crystalline form and very low rotatory poWer. 
A produd such as he describes can undoubtedly be ob- 
tained, but it is not difficult to separate bromocamphor 
from it, and its properties are certainly those of an impure 
material. It is desirable that this produd should be more 
fully examined, and its nature definitely established, in 
view of the interest attaching to isomeric cis- and trans- 
modifications of camphor derivatives ; the account given 
by Marsh is incomplete as it stands, and it is to be hoped 
that he will study further the adion of bromine on cam- 
phor in presence of alcohol. 

Mr. Marsh, in reply, said he had no doubt as to the 
existence of the second bromocamphor. He regarded the 
adion of bromine on camphor as very considerably modi- 
fied by the presence of alcohol, which, by reading at once 
with the bydrobromic acid to form ethyl bromide, favoured 
the existence of the unstable isobromocamphor. The 
isobromocamphor has been obtained in crystals having a 
definite melting-point. Its specific rotation is more than 
100^ lower than that of the ordinary modification, while 
it is also lower than that of camphor itself. When dis- 
tilled it it converted partially, without appreciable decern* 



New Derivaiiveifrom AlphA-Dibromocamphor, 



314 

position, into the ordinary modification, the rotatory 
power after one diBtilUtion being raised about 50®, whilst 
ordinary broniocamphor may be readily obtained from the 
distilled produA by crystallisation from alcohol. 

•14a. "N/w Derivatives from a-Dibromocamphor,'* 
By Martin O. Forster, Ph.D. . . . ^ • 

Early in this year a preliminary note was published in 
the Proceedings (p. 4), describing the behaviour of a-di- 
bromocamphor towards nitric acid, an investigation 
undertaken at the suggestion of Professor Armstrong. 
It appears desirable to place on record the results which 
have since been obtained in this connexion. 

It has been already stated (loc. cit.) that a compound 
of the formula CoHuBraOa is produced when o-dibromo- 
camphor is aded on by fuming nitric acid {d, i'52), and 
that redudion with zinc dust and alcoholic ammonia 
converts this substance into a compound of the formula 
CxoHi3Bt02. A fuller investigation has shown that the 
composition of theie produas is represented by the 
formula C,oHx4BraOi and CioHxsBrO, respeaively, 
which, in fad, correspond more closely to the analytical 
results already published than do the formulas previously 
chosen. 

The compounds CioH^BraOa and CioHxsBrOa having 
given rise to numerous derivatives, it has been found ne- 
cessary to adopt some system of nomenclature by means 
of which they may be designated, and the scheme which 
is now proposed has been seleAed because it aims at re- 
presenting in the name of a derivative the class of com- 
pounds to which it belongs- It having been found that 
the initial compound CioH^BraOa has the properties of a 
laaone,this substance will be referred to as dibromo- 
eampkolid; the produa of its reduaion, CloHisBrOa, is 
an unsaturated (carboxylic) acid, and will be called 
bromocamphcnnic acid, the termination "olid ' being 
significant of Uaones, whilst eihylenic linking is repre- 
senied by the syllable •* en." . . ^ ,. u 

Dibromocampholid, CxoHuBraOa, is obtained by the 
aaion of fuming nitric acid (rf. 1*52)00 a-dibromocam- 
phor in quantity amounting to about 10 per cent of the 
material used ; it crystallises in long, colourless, trans- 
parent needles, and melts at 15a**. Alcoholic potash 
converts it into the lactone, CX0HX4O3, which melts an 
174% *n<l y»«*^» *^* ^"'' CxoHx604on hydrolysis; the 
laaone is readily converted by bromine into the bromo- 
lactone, CioHxsBrOa, which crystallises from alcohol m 
lustrous silky needles, and melts at 196—197% 

Bromocamphorenic acid. C.oHxsBiOa. is formed when an 
alcoholic solution of dibromocampholid is reduced with 
line dust and ammonia ; it crystallises from alcohol in 
thin, lustrous, six-sided plates, and melts at 159 . The 
barium salt contains aHaO, and the Mine, copper, and 
silver salts are also crystalline; the methyltc salt is a 
fragrant oil, which boils at 255° under a pressure of 767-5 
m.m. The unsaturated charaaer of bromocamphorenic 
acid is indicated by its behaviour towards potassium per- 
manganate, which is immediately decolourised by the 
solution in sodium carbonate, a dicarboxylic actd being 
produced having the formula CxoHxeOe. and melting 
at 184*; a cold solution of bromine in chloroform is at 
once decolourised by the acid in the same medium, hy- 
drogen bromide and dibromocampholid being formed. 

Campkorenic acid, CxoHxcOa, i« obtained by reducing 
a boiling alkaline solution of bromocamphorenic acid 
with sodium amalgam ; it crystallises from alcohol in 
colourless needles, and melts at i6x% The sodium salt 
crystallises from strongly alkaline solutions in silky 
needles ; the mcthylic salt is a colourless oil, which boiU 
at ax5' under a pressure of 7675 m.m., and has the odour 
of camphor. The anhydride. CaoHaoOj, melts at 84-85 



fCBBIIICALNBWa, 

\ Dec. a?. i8«5- 



a-Bromocampholtd, CxoHxsBrOai 



is obtained by the 
acid on bromocam- 



aaion of concentrated sulphunc 
phorenic acid, and is isomeric with that substance ; the 
produaion of an isomeric Uaone under the influence of 
sulphuric acid, and the formation of a bromoUaone on 



treatment with bromine, are features which charaaerise 
/Sy-unsaturated acids. a-Bromocampholid crystallises 
from alcohol in lustrous plates, and melts at 9a— 93*^; it is 
indifferent towards bromine, and is hydrolysed by a 
boiling aqueous solution of barium hydroxide. 

fi'Bromocampholid is isomeric with the foreeoing sub- 
stance, and is formed from camphorenic acid or the sodium 
salt and bromine ; it crystallises from ether in transparent 
prisms, and melts at 63% It is indifferent towards bromine, 
and when the alcoholic solution is reduced with zinc dost 
and ammonia, camphorenic acid is fnrmed. 

Campkolid, CxoHxeOa* is obtained by dissolving cam- 
phorenic acid in concentrated sulphuric acid, the change 
being parallel with that attending the conversion of 
bromocamphorenic acid into a-bromocampholid ; it is 
very readily soluble in most organic solvents, but sepa- 
rates from petroleum in minute white crystals, and melts 
at 176—177°. Campholid is very volatile, and sublimes 
slowly below 100° ; it resembles camphor in appearance, 
and has the odour of that substance. It is indifferent 
towards bromine, but yields an acid, CxoHxsOj, on hydro- 
lysis, which crystallises from ethylic acetate in magnificent 
lustrous needles, melting at 179. 

♦143. " Isomeric it - Bromo -a • nitro Camphors.*^ By 
Arthur Lapworth, D.Sc, and F. Stanley KiPPtNG, 
Ph.D., D.Sc 

It has already been shown by one of the authors {Prac, 
Chem, Soc, cxlviii., 39) that ir-dibromo-camphor is at- 
tacked by concentrated nitric acid, and that the produd 
consists partly of a bromocamphoric acid and partly off 
an oil, which, by the aaion of alcoholic potash, yields a 
bromonitro-camphor. 

It has now been found that if this oil be boiled with 
concentrated nitric acid until it is free from ir-dibromo- 
camphsr ; it subsequently solidifies to a crystalline cake, 
from which bromonitro'Camphor can be easily isolated. 
(Found C= 34*05 ; H =4*21; Br =44-98 per cent. Calc 
C«33-8o; H=3*67; Br =4505 percent). 

This compound separates from cold light petroleum m 
the form of long flat needles, meling at 54% and is inso- 
luble in water, but soluble in most of the usual organic 
solvents. When boiled with alcoholic potash it loses 
I atom of bromine, and affords the potassium salt of the 
bromonitro-camphor previously described (^loc, cit.)^ The 
further investigation of this bromonitro-camphor leads to 
the conclusion that it is polymorphous. The crystals 
from chloroform and petroleum melt sharply at 133— «34% 
and solidify on cooling to a crystalline mass, which 
fuses at 126®; this is also the melting-point of crystals 
obtained from alcoholic or dilute acetic acid solutions, 
whereas large pyramidal crystals deposited from a mix- 
ture of ethylic acetate and chloroform melt at io8% im- 
mediately solidify, and melt once more at 126% A 6 per 
cent solution gave [a] d = + 33*04« 

Reduaion of v-bromo-a-nitro-camphor with sine dnst 
and acetic yields an amido-compound with a strong am- 
moniacal odour, which is probably ordinary amido-cam- 
phor, as it contains no bromine, and agrees in properties 
with the compond described by Schiff {Ber,, xiii., 1404). 

If, however, the bromonitro-camphor be carefully re- 
duced with sodium amalgam in aikaline solution, it is 
converted into a new v-bromo-a-amido-camphor.-— 

CxoHx4BrONHa. 
the hydrochloride of which crystallises from water or ace- 
tone in colourlesss needles or plates. (Calculated for 
CxoHx4BrONHaHCl, 0=42-46; H =603 ;Br+Cl«:40'8i. 
01 = 12*56. Found, 0=42-57; H=6-05; Br+Cl=40-36. 
01 = 1270). 

The oxalate is almost insoluble in water, and melts at 
201**; the platinichloride forms silky yellow needles, melt* 
ing with decomposition about 2x9^ 

v-Bromr-anitro-camphor dissolves in hot hydrochloric 
acid, and the solution on cooling deposits crystals of a 
new compound, which is soluble in hot sodium carbonate 
solution, and separates from bensene in flat needles melt* 



GtoufiCAL Hmrt, I 
Dec S7, 1095. ' 



w-Bromocampkoric Acid. 



315 



log at X37". This sobstance is an isomeric ir-bromo-a- 
nitro-caraphor. (Found, C » 43*57 ; H « 5*32. Calculated, 
C">43*47; Ha 5*07 per cent). 

It differi from its isomeride inasmuch as it dissolves 
readily in hot water, crystallising from the solution in thin 
plates melting at xo8' ; it is also much less soluble in 
tthylic acetate and in benzene, and it yields a blue copper 
salt, that of its isomer being pink. Its specific rotation 
ia also much greater, viz., [a]o » +52*7. 

That these two v-broroo-a-nitro-csmphor are struc- 
turally identical is probable from the fadk that they both 
yield v-bromo-campboric acid on oxidation with nitric 
acid ; it is concluded, therefore, that the difference be- 
tween these two substances is of the same nature as that 
•obeisting between cis-and trans modifications of cycloid 
derivatives. 

•144. •• Dtfivaiivtt of w-Bromocamphoric Acid.** By 
F. Stanlbt Kippino, Ph.D., D.Sc 

ir>Bromocamphoric acid, CioHisBr04, prepared by 
oxidising ir-dibromo- camphor (Proc. Chim* Soc,, cxlviii., 
33), is readily aded on b^ alkalis giving, according to the 
conditions of the experiment, a laAonic acid, C10H14O4 

!m. p. 164^x65*'), or ir-hydroxy camphoric acid, CX0H16O5 
Proc.. cli.. 88). 

The ladonic acid is the initial, and not the final, pro- 
do A of the aAion, as was at first supposed ; when heated 
with excess of aqueous potash it is converted into a salt 
of the vhydroxy acid. The hydroxy acid, treated with 
acetic chloride, yields an acetyl derivative of its anhy- 
dride ; this substance crystallises from ethereal petroleum 
10 prisms melting at 89—90^, and is dimorphous, another 
modification mehing at 86— 87^ When the hydroxy acid 
is distilled, it yields as principal produA a ladonic acid, 
CxoHt404 (m. p. about 226% isomeric with the compound 
referred to above, and identical with that obtained by 
beating ir-bromo-camphoric acid with quinoline {he, cit.). 
The ladonic acid of lower melting-point is also converted 
on distillation into the isomeride of higher melting-point, 
whereas the latter, on fusion with potash, gives the 
v-hydroxy acid. 

v-Hydroxycamphoric acid and the ladonic acid melting 
at 164—165*' are readily oxidised by nitric acid, giving an 
acid of the composition CX0H14O6 (he. cit,), but the lac- 
tonic acid of higher melting point is exceedingly stable, 
and teems not to be attacked by boiling nitric acid ; on 
prolonged treatment with alkaline permanganate, how- 
ever, either at ordinary temperatures or at loo*', it yields, 
amongst other produds not yet investigated, a small quan- 
tity of a derivative of dihydroxycamphoric acid, 
CtoH|o06f namely, a hydroxy ladonecarboxylic acid of 
the composition CtoHi405. This substance crystallises 
from hot water, in which it is readily soluble, in long, 
slender needles, and from a mixture of moist ether and 
ethylic acetate in well-defined transparent prisms melting 
at about 265^; these crystals lose iHaO, and become 
opaque when heated at zoo*, so that the substance is 
probably a monohydroxyladonic acid of the composition 
CfoH 14054- HaO, and not a dihydroxy compound. Its 
identity wiih the acid obtained from v-dibromocamphoric 
anhydride (see following note), and the fad that the lac- 
tone ring in the substance (m. p. 226 ) from which it is 
derived is very stable, lead to the conclusion that it is 
the ir-hydroxy group which has taken part in the ladone 
formation. 

It leems probable, from the fads already established, 
that the fr-bromine atom in ir-bromocamphoric acid is a 
Gonstituent of a - CH«Br group. 

145. ** w-Dihfomocampkofic Acid and its Derivatives,** 
By F. Stamlby Kippimo. Ph.D., D.Sc. 

The derivatives of v-bromocamphoric acid, which have 
been referred to in the preceding and in previous notes, 
are to stable that attempts to obtain from them simple 
oxidation produds containing less than 10 atoms of car- 
bon have so far been unsticcessful ; as they also resist the 
adUoA of bromine, or give with it ilMefined substances. 



experiments were made with the objed of brominating 
ir-bromocamphoric acid itsel/, in the hope of obtaining a 
dibromo-derivative which, on treatment with alkuit, 
would yield produds more easily oxidisable than those 
prepared from the monobromo acid. 

W'Dibromocamphoric anhydride, CioHiaBraOj, it ob- 
tained on treating dry v-bromocamphoric acid with 
bromine and amorphous phosphorus under the usual 
conditions ; it crystallises from chloroform in large trans- 
parent plates, melts at about axo* without decomposing, 
and is readily soluble in warm chloroform, but very 
sparingly in cold ether, and insoluble in cold water and 
cold sodium carbonate solution. 

W'Dibromocamphoric acid, CioHi4Bra04, is deposited in 
small plates when the anhvdride is dissolved in hot con- 
centrated nitric and the solution evaporated on the water- 
bath; it melts and decomposes at axo— an", and ia 
readily soluble in cold ether, but insoluble, or nearly so, 
both in chloroform and in hot water. It dissolves in dilute 
sodium carbonate solution with effervescence, and on 
acidifying the solution after heating for a few minutes 
ir-bromocamphanic acid (see below) is orecipitated* 
ir-Dibromocamphoric acid is stable at xoo°, but when 
heated at its melting-point, part is re-converted into the 
dibromo-anhydride and part is transformed into v-bromo- 
camphanic acid with liberation of hydrogen bromide. 

it'Bromocamphanic acid, CxoHi3Br04, is formed when 
the dibromo-anhydride is boiled for some hours with water 
and a little alcohol ; it separates from cold dilute alcohol 
in fern- like crystals which contain water, but from hot 
water and from a mixture of chloroform and ethyl acetate 
anhydrous crystals are deposited ; it melts at x^ — XTT^t 
and is soluble in sodium carbonate aolution with effer- 
vescence. 

On prolonged boiling with water, or on heating with 
aqueous alkalis, r-dibromocamphoric acid is converted 
into an acid melting at about 265^ and identical with the 
oxidation produd described in the preceding note. 

X46. ** w-Bromocamphorie Acid. By F. Stanley Kip* 
PINO, Ph.D.,DSc 

The fad that ir-bromocamphoric acid is obtained di- 
redly on oxidising irdibromocamphor, whereas the 
v-dibromocamphoric acid can be prepared from the cor- 
responding anhydride (see preceding abstrad), led the 
author to try and isolate the unknown bromocamphoric 
acid corresponding with Wreden's bromocamphoric anhy- 
dride : this was accomplished by hydrolysing the 
anhydride with concentrated nitric acid under suitable 
conditions, but the yield was comparatively small, mott 
of the anhydride bein^ recovered. 

The bromocamphoric acid, which, it is proposed, should 
be distinguished from the isomeric ir-acid by using the 
initial letter of Wreden's name (he having first prepared 
the anhydride), crystallises from a mixture of chloroform 
and ether in large transparent orthorhombic pyramids, 
having the composition CxoHt5Br04. (Found, CaB4a*9 
H«5*4 ; theory, C«43*o, H-i5*4 per cent). It dissolves 
freely in ether, but is almost insoluble in bensene and 
chloroform, and melts at 195— xgd^, charring slightly and 
effervescing; it is readily soluble in todium carbonate 
solution, by which it is rapidly decomposed, yielding or- 
dinary camphanic acid. When heated for a short time 
with acetic chloride the acid is re-converted into the an- 
hydride from which it is derived. 

Aschan (B#r., xxvii., 2xt2, and xxviii. ; Ref.Qaa) has 
recently isolated an acid, which he designates /-bromiso- 
camphoric acid ; this compound appears to be different 
from the acid which forms the subjed of the present com- 
munication, but Aschan's original paper being at present 
inaccessible, this point cannot be nnally settled. 

The author also refers to a curious phenomenon ob- 
served in crystallising sv-bromocamphoric anhydride from 
chloroform ; in some cases the solution becomes highly 
supersaturated, and crystallisation ultimately takes place 
with almost explosive violence. 



3t6 



Modern Copper Smelting. 



f Crbmical MBWt,- 
1 Dec 27. S895. 



^ 
^ 



X47. •• wChlorocampkoric Acid,** By F. Stanley 
KiPPiNO, Ph.D., D.Sc., and William J. Pope. 

Optically inadive camphor Bulphonic chloride (Kipping 
and Pope, Trans. ^ 1893, ixi"., 548) yields, on distillation, 
two produds, namely, a crystalline inadive v-chloro- 
camphor and an oil {Trans., 1895, Ixvii., 371). 

When the mixture of these two compounds is heated 
with nitric acid the oil is rapidly oxidised and passes into 
solution, but ir-chlorocamphor, like ir-dibremocamphor, is 
attacked and dissolved rather slowly. 

On cooling the solution, crystals and an oil are deposited. 
The crystalline substance is ir-chlorocamphoric acid, the 
oil being probably ir-chloro-a-nitrocamphor, the forma- 
tion of which, under the above conditions, would be ana- 
logous to that of ira-dibromc-a-nitrocampbor from iro-di- 
bromocampbor (see preceding note by Lapworth and Kip- 
ping) ; other substances are present in the filtrate from 
nitric acid, but they have not yet been examined. 

Inadive ir chlcrocsmphoric acid,CioHi5C104, resembles 
v-bromocamphoric acid very closely in ordinary proper- 
ties. It is very sparingly soluble in hot water, from which 
it crystallises in small lustrous prisms, melting at about 
Z95^ It is almost insoluble in chloroform, but dissolves 
freely in ether, methyl alcohol, and acetone. 

This chloroacid is doubtless struAurally similar to w- 
bromocamphoric acid, but whereas the latter is a deriva- 
tive of an optically aAive ir- bromocampbor, the chloro- 
acid is derived from an inadive or racemic halogen deriva- 
tive of camphor. 

A chlorocamphoric anhydride has been recently de- 
scribed by Aschan {Ber., xxviii., Ref. 922), but this sub- 
ttanct is derived from an acid strudurally as well as opti- 
cally different from ir-chlorocamphoric acid. 

(To be cootinued). 



NOTICES OF BOOKS. 



Modern Copper Smelting. By Edward Dyer Peters, 
Jun. Seventh Edition, Re-written and greatly En- 
larged. London and New York : The Scientific Pub- 
lishing Company. 1895. ^^o., pp. 642. 
When a work of this character has passed through the 
ordeal of seven editions, we may feel sure that it has 
given satisfadion to pradical men. 

The present edition takes due account of certain capital 
improvements in the metallurgy of copper, such as the 
introduAion of automatic calcining furnace, the rapid de- 
velopment of the copper Bessemer process, the improve- 
ments in blast-furnaces and reverberatories, and " per- 
haps, above all, by the gradual dawning of the idea that 
although copper is worth fifteen times a« much as iron it 
is not absolutely necessary to expend fifteen times as 
much money in handling and treating its ores." 

This is a specimen of the dry humour which crops out 
here and there in this work. Thus we read that ** it is 
easier to run a furnace on a novel plan with men who 
know nothing about it than with those who know too 
much.'* 

On again speaking of cliques among workmen, Mr. 
Peters writes :— ** A judicious mixture of nationalities will 
often prevent the deceptions and the attitude of passive 
resistance to all improvements which charadlerise a body 
of experienced workmen of any one nationality. A mix- 
ture of Irish and Cornish furnace-men with an American 
foreman usually works well, as the men all dislike and 
distrust each other so much that they find it impossible 
to combine against the common enemy.*' 

The chapter on the distribution of the ores of copper 
loses much in value by its being confined to the North 
American deposits. 

Automatic sampling is an improvement which must do 
away with some very unedifying disputes and recrimina- 



tions, not merely in metallurgy, but in all the " heavy ' 
chemical industries. 

The Cornish fire assay of copper ores — a *' Pi'erde- 
methods'* as we have heard it called in Germany — is 
spoken of with too great leniency. A process which gives 
results short of the truth, not by a constant value, but by 
a proportion which fluAuates in different ores, ought no 
longer to be recognised. It is an error to say, as the 
author does in a foot-note, that *' in England all analytical 
chemists are called assayers," though the exaA connota* 
tion of the two terms has never been authoritatively de* 
fined. The eledtrolytic process for the determination of 
copper is very fully described and illustrated. 

Under the cyanide assay, attention is called to the sub- 
stances which interfere with the result. Arsenic and 
antimony rank as the most dangerous substances, as also 
zinc in proportions exceeding 4I per cent. Ferric 
hydroxide, if present in quantity, occludes copper and in- 
troduces a serious error. Yet we once met with a chemist 
who considered he had effedled an improvement in this 
process by omitting to filter off the precipitate of ferric 
hydroxide before titrating with cyanide. 

In the improved cyanide method of A. H. Law, the 
copper is first precipitated from the solution of the ore by 
meansof metallic aluminium, the deposit is re-dissolved 
by means of nitric acid. Silver, if any, is precipitated as 
a chloride and filtered off. For the subsequent titration 
care is taken that all the conditions shall be identical, 
such as the total volume of the solution, the proportion of 
ammonia used, and the working temperature. 

The iodide process is very highly spoken of. After 
giving a table of results, the question is put — ** Can the 
eleArolytic method improve upon this ? " 

Pyritic smelting, in the strid sense of the term, t./., 
without the use of any carbonaceous fuel, is not, the 
author considers, sufi5ciently developed to warrant its 
introduAion, except experimentally. 

The Bessemer treatment of copper forms the subjeA of 
a very interesting chapter. 

The most harmful substance which may be present in 
a matte is bismuth, as it adheres to copper most ob- 
stinately ; and, according to the experiments of Hampe, 
renders it red-short even when occurring in such small 
proportions as 0*02 per cent. 

The eledrolytic refining of copper seems to have proved 
very successful in America, as shown by the enlargement, 
of existing eleArolytic works, and the establishment of 
new ones on the same principle. 

A most valuable feature of the work must be recognised 
in the numerous and elaborate illustrations. 

It is scarcely needful to add that the present edition of 
this book must be welcomed as a boon by all persons con- 
neAed with the copper industry. 



Treatise on Distillery. Distillers* Microbiology. Ferments 
and Fermentation, (•• Trait6 de Distillcrie. Micro- 
biologie du Distillateur. Ferments et Fermentation ")• 
By M. P. GuiCHARD, Member of the Chemical Society 
of Paris. Paris : J. B. Bailliire et Fils. 1896. Pp. 
392, i6mo. 

The study of fermentation is not merely a technological 
question. It was the earliest subjea which led us to a 
clear conviaion that chemical phenomena may involve 
and depend upon biological processes. This fad is of. 
profound scientific importance. It shows us that the 
simpler sciences of Comte's hierarchy may and do require 
a knowledge of those more complex and less general. 

But the work before us does more than it promises. It 
considers the animal and vegetable proteic matters, the 
soluble and figured ferments, and the industrial analysis 
of fermented produds. 

The author gives a historic study of the process of fer^ 
mentation. He traces the discovery of alcohol to Abucasi 
and Arnold, of Villanova, and quotes a recipe from 



c>«2»<^f^*'} Place of Helium in the Classification of Elements. 317 



Ramon LuUy for its prodoaion. He briefly traces the 
gradaal development of the theory of fermentation and 
putrefaaion down from those early experimentalists to 
the fall light thrown upon the subjea by Pasteur. 

In the second part, M. Guichird considers the albo- 
nenoid substances in the widest sense of the word, the 
albumens, globulines, peptones, coUagens, caseins, to- 
gether with the genesis and transformation of the 
albumenoids in the organic economy. 

The third sedion is devoted to the soluble ferments, 
diasuses, xymoses or enzymes, and the theory of their 
aAion. 

In the fourth sedion, we pass to the figured ferments — 
moulds, their aerobic and anaerobic life; yeasts, their 
origin, purification, and chemical composition. There is 
alto an account of the reagents and pigments used in their 
microscopic examination. The microscope here figured 
and recommended is that of V6rick. For photographing 
Che ferments we find the instruments of Dr. Roux (manu- 
fadured by V€rick) and of Nachet recommended and 
ahown in the illustrations. As useful reagents, the 
author recommends a hot solution of glycerm, diluted 
•odium sulphate, and alum in veiy dilute solution, potas- 
sium acetate in an aqueous solution, the reagents of Bar- 
foed, Fehling, Millon, and Ehrlich. The last-mentioned 
consists of 2 parts of potassium dichromate and 0*50 part 
copper sulphate in zoo parts water. The stains or dyes 
found most useful are described at some length. 

In the fifth sedion we have the classification of fer- 
mentations, as the alcoholic, the baderial (under which 
head are given some interesting fads as concerning the 
vital conditions of the Schizomycetes and the low tem- 
peratures which they are able to support), the acetic, the 
ladic, butyric, panary, gluconic, and mannitic. 

The sixth sedion is occupied with the industrial ana- 
lysis of the produds of fermentation. 

A seledion of useful tables conclude the work. 

M. Ouichard's book may be regarded as useful, both 
from a pradical and a theoretical point of view. Few 
chemists can now afford to overlook the multiform and 
far-reaching agency of fermentation. 



CORRESPONDENCE. 

ON THB 

PLACE OF HELIUM IN THE CLASSIFICATION 
OF ELEMENTARY SUBSTANCES. 

To tki Editor of thi Chemical News, 
Sir,— In the Chbmical News, vol. Ixxii., p. 305, 1 notice 
that Dr. Gladstone maintains his wrong assertion ** that 
Ihe successive differences between the atomic weights of 
adjacent members of the metals in the first group in 
Mendeleeff's table showed that these differences increased 
at we go downwards,*' notwithstanding that the assertion 
was disproved by reference to this table, at well as to the 
one set forth in my former letter. 

Judging from the remarkable statements now made by 
Dr. Gladstone, it would appear to be much more probable 
that he has forgotten the numbers he wrote on the black- 
board of the Physical Society than that the official record 
of these numbers is incorred. 

As Dr. Gladstone, at the meeting of this Society, ex- 
pressed doubt as to the elementary charader of helium, 
he is hardly entitled to have an opinion on its place in 
any classification until he has first convinced himself on 
this point. ... 

His observations on the relations of the atomic weights 
10 the year 1853 have little in common with those set 
lorth in my tables in the Chemical News of 1878 (vol. 
axxviii.), which, as will be seen, anticipated everything of 
value that Dr. Gladstone advanced retpeding the atomlg 



weights in his Address to the Chemical Sedion of the 
British Association in 1883. No chemist knows thlt 
better than Dr. Gladstone himself.— I am, &c., 

H. WiLDB. 
Decembtrsi, iBgs. 



CHEMICAL NOTICES FROM FOREIGN 
SOURCES. 



NoTB.«AU decrees of tsmperature are Csotlgrads aalsss otherwise 

eipreitsd. 

Combes Rendus ffeMomadaires des Sianca, de VAcademii 

des Sciences, Vol. cxxi., No. 23, December 2, 1895. 

Pretence of Sodium in Aluminium produced by 
Ele^rolyait. — Henri Moissan. — This memoir will be 
inserted in full. 

Origin of Argon and of Helium in the Gates given 
off by certain Sulpharout Springs.— L. Troott and L. 
Guvrard.— (See p. 309). 

Studies in Molecular Phyaies.— Ch. V. Zenger.— 
The author announces that he has found a simple relation 
between the density and the specific heat of the elements. 
This relation seems to him to throw a new light 00 the 
molecular adions which have governed the formation of 
the elements. Perhaps by imitating the charaderistic 
conditions of the most remote geological epochs we may 
succeed in transforming the physical and chemical proper- 
ties of the elements themselves. 

Relation between the Intensity of Light and the 
Chemical Decompotition which it producet. Bx* 
periment with Mixturet of Ferric Chloride and 
Oxalic Acid. — Georges Lemoine.— The decomposition 
occasioned by light in solutions of ferric chloride and 
oxalic acid may serve for measuring the intensity of the 
light although the readion is exothermic, for the heat dis- 
engaged is rapidly dissipated in the ambient medium, and 
the chemical transformation takes a permanent course. 
We may conclude approximately that the chemical de- 
composition of the mixture of ferric chloride and oxalic 
acid is proportional to the luminous intensity. 

Pretence of Argon and Helium in a Source of 
Natural Nitrogen.— Ch. Moureu.— (See p. 310). 

Experimental Determination of the Agglutinatiof 
Power of Coal.— Louis Campredon. — There is no corre- 
lation between the oom position of a coal as established 
by analysis and its caking power. 

On Chromium Amalgam and on tome Propertiet 
of Metallic Chromium.— J. F€rH.— The author obtains 
chromium-amalgam by the eledrolytic method. The pro- 
dud obtained had the composition rlgjCr. On submitting 
this compound to a pressure of 200 kilos, per square centi- 
metre between folds of filter-paper another amalgam wat 
obtained of the constant composition of HgCr. 

Synthesis of Complex Amides.— Albert Colton.— 
Not suitable for useful abridgment. 

New Instances of Superpotition of the Optical 
Effetftt of Atymmetric Carbons.— Ph. A. Guye and 
Ch. Goudret.— Not suitable for abstradion and not of 
sufficient importance for insertion in exUnso. 

RevM€ UniverseiU des Mines ei de la MdaUur^ie, 
Series 3, Vol. xxxi.. No. 2. 

Detulphuration of Catt Metal by the Saniter Pro- 
cess.— Krewtxoff.— The ingredient used is chiefly calcium 
chloride. In samples obtained the proportion of sulphur 
before the addition of the calcium chloride was from 
0*029 to 0*035. ^^^ ^ procett it wat reduced to 0*019 
to 0*016. 



3i8 



Determioation of Salpbar in Organic Subttancet. 
L. L. de Koninclc and £d. Nihoal. — The aothors submit 
the specimen operated apon to combustioo with a mixture 
which they call nitro-lime. At least 5 parts of quicklime 
are incorporated with x part of dry calcium nitrate. The 
5 parts of quicklime, in minute fragmeats quite anhydrous 
and free from sulphate and silicate, are placed in a porce- 
lain capsule and gradually sprinkled with z part of dry 
calcium nitrate dissolved in | part water, applying a 
moderate heat if needful to set the readion in progress. 
The method of operation has a general resemblance to 
that used in the Varrentrap and Will process for deter- 
mining nitrogen. 



Meetings for the Week. 



I Cbbmical If •«•• 
I .Dec 97, 189s- 



MISCELLANEOUS. 

The Bast London Bzhibition. — It is announced 
that in June next there will be held, in the People's 
Palace, a General Exhibition of the Trades, Industries, 
and Arts of East London, and of the work of the Poly- 
technics and Technical Institutes. It includes the fol- 
lowing SeAions : — Exhibits of manufaduring aud trading 
firms, the work of individual craftsmen ; exhibits by indi- 
vidual students and apprentiees; exhibits by students, 
colledively and by institutions ; women's work, and loan 
exhibits of works of art. The first Sedion comprises the 
following groups :— The building trades ; the silver trades, 

{goldsmiths, jewellers, &c. ; printing and allied trades ; 
eather trades ; clothing trades ; engineering and metal 
trades ; food and cookery ; furnishing and brush and basket 
trades ; shipping and navigation ; tobacco trades ; glass 
and pottery trades; coach-makers, wheelwrights, and 
auxiliary trades ; textile trades ; horticulture ; aero- 
nautics ; brewing, and manufadure of aerated waters ; 
fuel furnaces, stoves, and fireplaces ; india rubber ; photo- 
graphy ; educational and physical training appliances ; 
toys and games ; bicycles and tricycles ; coopering ; mu- 
sical instruments ; chemical manufadures— a department 
in which we have still much to learn ; fire-arms and ex- 

J>losives ; and, lastly, taxidermy. This last item will, we 
ear, include much that is injurious, if not absolutely 
criminal, f. #., the destrudion of harmless and useful birds 
and inseds at the bidding of fashion. Under Sedion II. 
we find scientific instrument making, a department in 
which we have, nationally speaking, no little room for 
improvement. Prixes will be awarded in the various 
groups for excellence of workmanship. We hope that the 
Exhibition may prove successful in every sense, and that 
it may revive the original objed of the People's Palace. 



MEETINGS FOR^THE WEEK. 

Tuesday. Dec. 3itt. ) Royal Institution, 3. {The Christmas Lee* 
Truksday, Tan. and. > tares). " Sound, Hearing, and Speech," 
Saturday. Jan. 4th . ) by Prof. J. G. McKendrick, B^.D., F.R.S. 
Friday, 3rd.— Quekett Club, 8. 

— Geologists' Association, 8. 

FOREIGN SCIENTIFIC BOOKS. 

IMPORTERS OP FOREIGN BOOKS, 

Receive regularly all Foreign Scientific Books. 

Catalogues and lisu post free on application. 

24, Henrietta Street, Covert Garden, London ; 

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and 7, Broad Street, Oxford. 



MICA 



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P. WIQQINS ft SONS. };i;^SiTn;riesI'l;cf, Loodoft. 

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JUST PUBLISHED. 
446 pagts aud loi lUustratioms, PriuUs,^. 

A TREATISE ON THE MANUFACTURE 

SOAP AND 'candles, 

LUBRICANTS, AND GLYCERIN. 

By WM. LANT GARPEKTER, B.Sc. 

Second Bditioo, Revised mod Enlarged by HENRY LEA8K 

CONTENTS. 
Historical Epitome and Re''exences. Theoretical Principles. 
Raw Materials : Their Sonrcet and Preparation. 
Raw Materials : Refininc, Clarifying, and Bleaching. 
Raw Materials : Their Proximate Analysis. 
Canstic Alkali and other Mineral Salts. 

Manntaaure of Household Soaps : The Process of Saponificatioa. 
Treatment of Soap after its Removal from the Soap Copper: Codioc. 

Cutting, Drying, Moulding. *• 

Soap-~Filling and Sophisticating. 
Special Soaps : Household, Laundry, Floating, DIsinfeaant. Hard. 

water. Sand. Cold-water, Powders, Manuf«aiirers', Toilet. 

Transparent, Fancy, SolidiBed, Glycerin, &c 
Theory of ihe Aaion of Soap-Its Valuation and Aaalytis^Dtatri- 

bution and Position of the Trade. 
Lubricating Oils. Railway and Waggon Grease, &c. 
Candles— Raw Mai- rials, their Sources and Preliminary Treatment. 
Processes for the Conversion of Neutral Pats into Fatty Acids— The 

Maoufaaure of Commercial Stearin. 
The Manufaanre of Candles and Night-lights— Their Valne ea Ula* 

minanu. Glycerin. Bibliography. Index. 

E. ft P. N. SPON, las, Strand, London. 




OLD PLATINUM 

In any FORM PURCHASRD FOR CASH. 

Highest prices allowed by 

ROBERT PRINGLB ft CO., Gold and SUver 

Refiners, &c., 40 and 4a, Clerkenwell Rd., E.C. 

Send for Price List. 
Photographic Residues reduced and porchnsed* 

SULPHUROUS ACID. 

SULPHITES AND BISULPHITE OF LIME, SODA. Ac. 

HYDROGEN PEROXIDE, 10/30 vols. 

CARAHELS, Liquid and SoUd. 

BENNETT d JENNER, Stratford, London. 

AC£XONE# — Answering all requirementR* 

.A-OIID JLCETIO— Purctt and tweet. 

IBOIR-A.OXO— Cryit. and powder. 

CITIRIO— Cryat. made in earthenware. 

C3-.A.XiXjXO— From best Chinese galls, pnie, 

S-A-IiiaYIilO-By Kolbe'a ptoceea. 

TJLlSTlSTXO—^or Pharmacy and the Arta. 

LIQUID CHLORINE 

(Compreued in steel cylinders). 

FORMALIN (405^ CHaO)— AntigepUc and Preservative. 

POTASS. PERMANOANATB-Cryat., large and amaU. 

SULPHOCYANIDE OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIC-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AMD THE ARTS. 

Wholesale Agents— 

A. & M. ZIMMERMANN, 

6 A 7, CROSS LANE. LONDON, E.G. 



|aa. 10, 1898. 



INDEX.— SUPPLEMENT TO THE CHEMICAL NEWS. 



319 



INDEX. 



A BBRDBBN Univenity, 126 

Aberyttwyth College, uk 
Absorptioa speftra of liqaefied 

air, 65 
Accumulator, oew form, 2x1 
Acetic and formic acidt, ipecific 

heats of snperfosed. 98 
Acetones of the fatty series, 

latent heatt of evaporation 

of. 223 
Acetylene, toxicity of, 233, 306 
Acid. aAive amylacetic, 109 
ammoniom sodiam tungsutes, 

12 

Mchromtc, heavy metallic salu 

of, 281 
bone, dctermtoation of, 166 
bromocamphoric. 315 
botyric, estimation, 289 
camphoric, coostitution, i^ 
chlorocamphortc, |i6 
citric, formation of, 31, 165, 190, 

335. a57. aW 

from cane'tufar, 100 
cyannric, preparing, 57 
ethaneutracarbosylic, ethereal 

salts of, 48 
filtering glass cloth for, 306 
hydrochloric, aaion of, 221 

aAioQ of dry, 126 
hydrofluoric, aaion of, 278 
magentas, 198 
malonic aeries, 254 
moljrbdic, determination of, 



Mphtl 



aapbtholsislphonic, 109 
new ketonic, 245 

0itnc det^ioo of iodic acid 
in, 37 

of selenium, redaaion of, 156 

oxalic, and ftrric chloride, ex- 
periment with mixtares, 317 

paratungstic, 6z 

phosphoric, volumetric estima- 
tion, 28 

properties of solid carbonic, 49 

resorcylic, 233 

•elenions, determination, 2to 

solutions, ** standard,** 3, 84 

solphanilic, thio-derivatives of, 

totphoric, fomlng, 73 
urtaric. some readtions of, 

306 
thtoacetic, preparation of, 64 
uric, determioatioo of. 40 
Acidic oxides, aaion 01 certain, 

966 
Acidity of winet, Tolatile, 209 
Acids, tormic and acetic, specific 
heats ot soperfused, 98 
of toluene, disolphonic, 58 
optically aaire methoxy and 

propoxysuccioic, 233 
Mpnratioo of Tolatile fatty, 37 



Acids, succinic, 253 
sulphonic, six (Qchlorotolucnes 
and their, <8 

Acidylthiocsrbimides, 277 

Addey's Science and Art School, 
125 

Agricultural College. Cirencester, 
Royal. ixS 

"Agricultural Analysis*' (review), 
244 

"Agricultural Journal" (review), 
233 

* 'Agriculture, Cape of Good 
Hope Department of (re- 
view), 83 

Aikman, C. M., **Milk, its Na- 
ture and Composition*' (re- 
view), 279, ^ 

Air, aaion of on the must of 
graces, 49 
liquened absorption speara of, 

65 
percentage of argon in, 308 
respirabiiity in which a candle 
flame has burnt, 177 
"Aix-la-Chapeile, Programme of 
the Roysl Technical High 
School at" (review), 172 
Alcohol, elhylic, osmo ic pheoo- 
mena produced between ether 
and, 97 
Alcohols derived from a dextro- 
terebenthene eucslyptene, 49 
reagent for monovalent, 237 
synthetic, formation of mixed 
98 • 

Aldehyd, condensation prodoas 
of isovaleric, 98 
new formation of glycollic, 47 
valeric, 49 
•*Alkali Works Regulation Aa, 

Report" (review), 108 
Atkaline phosphides, 98 
AllQrl combined with nitrogen, 

deteaion of, 37 

Allen, A. H., ** C^iemistry of 

Urine" (review), 97 

use of mineral oil for excluding 

air in Pavy titrations, 11, 24 

Ally lie alcohol, phosphoric ethers 

of, 61 
Aluminium and poUssium phos- 
phates, certain deposits of, 

■ulphate, e£Bofescence of double 

ferrous, 289 
utensils, 161 
"Aluminium Sulphate, Manufac- 

ture of" (review), 83 
Alum in wines, 209 
Amalgam, chromium, 417 
Amines of the fatty smes, prepa- 
ration ol, S09 
Ammonia, determination of water 
in sulphate of, 6 
in sine powder, 37 
Amnumiacal aalta of lilvcr, X73 



Ammonium cyanate, transforma- 
tion into ures, 46 
sodium tungstates, acid, 12 
Amorphous state ot melted 

bodies, 185 
Amylacetic acid, aaive, 109 
Analyses of leucite basalt, recent, 

volumetric apparstus for ob- 
serving changes of colour in, 
243 

Aiulysis snd synthesis of argon, i 
of carbon steels, microscopic, 

report on paper on, i6x 
of cyanide solutions, technical, 

286, 29S 
of emerald, 245 
of fatty substances, 20Q 
qualitative, of a solution con- 
taining hydric sulphide, Ac, 
63 
quantitative, by means of elec* 
trolysis, 200 
of galena, 78 

**Analysis, Agricultural '* (re- 
view), 244 

**Analysis of Poods and Drugs, 
Aids to" (review), 244 

"Analysis, Prsaicsl Chemistry 
and Qualitative" (review), at 

"Analysis Quantitative Chemi- 
cal*' (review), 220 

"Analyst, Report of the Trinidad 
Government" (review), 232 

Aiulytical charaaers of a mix- 
ture of salts of barium, stron- 
tium, and calcium, 27 

"Analytical Chemistry, Manual" 
(review), 208 

"Anal7tical(;bemistry" (review), 
X84 

"Analytical Chemistry, Specific 
Foundations of (review), 
232 

Anderson, J. W., "Prospeaor's 
Handbook" (review), 22 

Anderson's College, 126 

Angeli, A., deteaion of hydroxyl- 
amine, 258 

Ang-khak, 103 

Anhydride, hypoiaitric, aaion of, 
98 

Anhydrides, non-existence of 
mixed, xto 

Aniline, aaion of, 98 

Anthraquinooe, some deriva- 
tives, 289 

Antimony, determination, 138 
phenomena observed m the 
precipitation of, 32, 43, 33 

Antipyrin, determination of, 238 
with di phenols, combinations 

of,22X 

Apiculated fermentation, x6i 
Apparatus, illuminating, for ob- 
serving the changes of colour 
in volnnatric analytea, a43 



Appleyard, I. R., and I. Walker, 
ethereal salts of ethanetatra- 
carboxylic acid, 18 
R., aaion of sulphur vapour, 
267 

direa-reading platinum ther- 
mometer, 267 
resistance and its change with 
temperature, 267 
Appointments, 23, m7 
Aqueous solutions of mercuric 

chloride, hydrolysis of, 62 
Archdeacon, W. H., and J. B. 
Cohen, preparing cyanoric 
acid. <7 
Araowski, H., aaion of heat 00 
carbon sulphide, 293 
double transposition of gaseous 

bodies, 221 
hydrolysis of the aqueous solu- 
tions of mercuric chloride, 62 
Argon, 14, 48, 247 
' determination of, 21X, 247 
fluorescence of, 13 
fluorescent spearum of, 7 
in air, percentage of, 308 
possible compound of, 31 
red spearum of. 289 
speara of, 66, 99 
synthesis and analysis, i 
and carbon, spearum of Ram- 
say's compound of, 99 
and helium, 89, 207 
combination of mainieslaffl 

with, X33 
discussion on, 223 
expansion of. 293 
in certain mineral wattn, 152 
in natural nitrogen, 310 
in the gases froin snlphnroat 

springs, 309 
refraaion and visooiity of, 

XS2 

Armature reaAion. so 
Aromatic amines, rormyl dariva- 
lives of, 37 
hydrocarbons, synthesis of, 49 
nitriles, new syndesis of soma, 
t34 
Arsenic, determination of small 
qusntities, 91 
separation from other ele* 
menta,igx 
Art and Science, Charterhouse 

Schools of, 130 
Artocarpus integriMia, conatito* 

ents of, 233 
Assay, wet, for copper, 70 
Assaying. 174 

Association, Bntiab, xay, 139, 
X4X, X49« 223 
address to the Chemical aae- 
tion, X4X, X31 

President's address, 127, X39 
Astre, C, aaion of potaaaa, asi 
potassium derivativaa of quti^ 
000 and bydroqaiBOoe» i6q 



3*> 



INDBX«-^UPPLBMBNT TO THB CHBMICAL MBWfi. 



|a».iOktf06. 



Atynmetric ketonic compoandt, 

aAion of, ito 
Athftoetco, ai., bMic nitrates, 

109 
Atmotpbere, third permanent 
radiation of the solar, 12, 14 
Atomic volume, relation between 

valence and, 9 
'*Atomic Weight of Cobalt, De- 
termination of** (review), 
333 
Atomic weight of carbon, 164 
of heliam. as9 
of molybdenum, 281 
of nickel and cobalt, 40 
of Btrootinm, revision, 18, 29, 

4«i 54. 7a 
of tungsten, 23X 
weights of nickel and cobalt, 
5t, 109 ^ 

report of committee, 93, 103, 
X57t i67t 179 
Auden, H. A., and O. J. Fowler, 
aAion of nitric oxide on cer- 
uin salts, 163 
Austen, T. P^ "How shall Yonng 
Men be Bdocated in Applied 
Chemistry" (review), 60 
P., the science of examining, 

P. T., and W. A. Horton, con- 
venient form of universal 
hand«clamp. 287 

Australasian Association for the 
Advancement of Science, 73 

Aso-compoonds, 133 



DACTBKIAL pigment, new, 

Baaeridde, new, 184 
Baker. J. L.. and A. R. Liog, 
aaion oi diastase on starch, 

Bautnd, M., composition of the 

rices importea into France, 

333 
preset vation of wheat, 62 
utensils sf aluminium, 161 
Bamberger, B., an explosion— >as 

a warning, 28 
Bangor, University College, xi6 
Barbier, P., and L. BouveauJt, 

essence of linal5e,73 
synthesis of aromatic hydro> 

carbons, 49 . 

Barium chloride, occlusion of, 

381 
Barley plant, chemical history 

of, 307 
Baromctera, temperature cor- 

redliona,304 
Barral, E., hexachlorobeoxene 

parachloride, 273 
Bthroe oAochlorophenola, 185 
asalt. recent analyses of leu- 

cite, S3 
Baaic nitrafba, too 
propartiea of the roaanihnes, 

Battcrsea Polytechnic Institute, 
130 

Banbigny.H., analytical charac 
ter of a mixture of aalu of 
barium, stvootium, and cal- 
cium, 37 

Baunek, O., determination of 
antimony, 138 

Bayard, P., progreaa of the blast 
furnace, 12 

Bedford. C. S., and A. O. Par- 
kin, derivauvea of madurin, 
233 

Benson, P. P.. nnd S. Shaw, 
argon in the gases of rock 

Iml. A., and M. Blaiae. attion 
of hyponitric anhydride, 08 
Behreos, H.. and A. R. Von 
Linge, microscopic examina- 
tion uf erode cement steel, 

Belfast, Queen's College, 123 
Beoxsldebyd, oximes of, 57 
Benzene, latent beat of evapora* 

tion of, 243 
Benxil,- condensation of, 36 



fienxyliden-campbor, oxidation 
produAs, 61 

Bergamot, essence of, 205 

Berthelot, D., combination of 
free nitrogen, zi 
description of fluorescent spec- 
trum of argon, 78 
new combination of argon, z 
new studies on the fluorescence 

of arson, Z3 
and M. Rivals, lactones or 
campbolenic olides, 49 

Berridge, D. J. P., adion of 
light on soluble meuUic iod- 
ides, 173 

Beitrand. u., deteAion of lac- 
case in plants, 73 
oxidising power of laccase, izo 
and A. Mallevre, distribution 
of peAase, 292 

Besson, A.^ oxidising properties 
of oxomsed oxygen, 61 

Battel, W., technical analysis of 
cyanide solutions, 286, 298 

Bichromic acid, heavy metallic 
salts of, 38x 

Bidwell, S., elearical properties 
of selenium, 30 

Birkbeck Literary and Scientific 
Inatitotion, 123 

Bismuth and cobalt, separation 

, •^t 91 

from mercury, separation of, 

64 
Bituminous waters, 269 
Blaise. M., and A. B£hal, aaion 

of hyponitric anhvdride,98 
Blancbsrd, £., remarks on i^ord 

Salisbury's address to the 

British Association, 1894, 

Blanshard, C. T., boiling point 
and the genesis of the ele- 
ments, 299 
specific volume and the genesis 
of the elements, 230, 237 
Blaat furnace, progress of, xa 
Blood pigment, examination of, 9 

spots, recognition of, 79 
Bloxam,C. L., J. M, Thompson, 
and A. O. Bloxsm, '* Chemis- 
try. Organic and Inorganic, 
Experiments" (review), 



W. P., qualitative analysis of 
solution containing hydric 
sulphide, hydrosulphide, &c., 

63 

Blue spaArum of argon, 99 

Blytb, A. W., ♦• Poisons • (re- 
view), 159 

Bodies, melud, amorphous sUte 
of, 183 

Boiling point and genesis of the 
elemenu, 299 

Bolam, H. W.. and T. Purdie. , 
optically a^ive methoxy and 
propoxysuccinic acids, 253 

Bolton, H. C, the latest disciple 
of Hermes Trismegistus, 

199 

Bonnet, A., direA fixation of 
certain metallic oxides, 281 

Booth, C, *' Life and Labour of 
the People in London" (re- 
view), 83 

Borax and standard acid eola- 
tions, 84 

Borchera, W., and W. Nernst, 
" Year-book of Elearo-Che- 
mistry** (review), 22 

Boric add, determination, x66 

Bomtrager, A., experiments with 
invert sugar, 236 
influence of lead acetates on the 
determination of inverted 
sugar by the Febting-Soxh- 
lei method, 186 

Bothamley, C. H , sensitising 
aaion of dyes on getati no- 
bromide plates, 187 

Bouchard, 0. H., argon and 
helium in certain mineral 
waters, 132 

Bottchardat, G , and M. Tardy, 
alcohols derived from a dex- 
tfo-terebenthene encalyp. 
tene, 49 



Bouveault, L., and P. Barbier, 
essence of linalde, 73 
synthesis of aromatic hydro- 
carbons, 49 

Bowden, M., elearo-magnetic 
effea, 20 

Bower, J. A., ** Simple Methods 
for Deteaing Food Adulter- 
ation" (review), 290 

Boyd, B. N., *• Petroleum" (re- 
view,36 

Bradford Technical College, xi8 

Braithwaite, I., redoaion of the 
oxides of iron. 21 X 

Bran, deteaion of ergot in. xo6 

Brauns, R., aaion of dry hydro- 
gen chloride^ 293 

Bread, distribution of the nitro> 
genons and mineral snb- 
stancea in, 306 

** Bread-Making " (review), 172 

Bristol Medical School, 126 
University College, xxy 

British Asaodation, X27, 139, 
X4X, X49, 223 
President's addreaa, 127, X39 

Brochet, A., and R. Cambier, 
haxametnylenetetramine, X07 
preparation of monomethyl- 
amine, X98 

Brociner, L., toxicity of acetyl- 
ene, 306 

Bromocamphoric acid, deriva- 
tives, 313 

Brown, H. T.. and G. H. Morris, 
the isomaitose of C. J. Lint- 
ner, 43 

Bmce, J., and W. P. Wynne, 
disuiphonic acids of toluene, 
38 

Bruylants, G., novel reaaions of 
morphia, 32 

Burker, £., new ketonic acid, 

Batter, examination, 246 
Butyric acid, eatimation, 389 



PALAVBRITB from Cripple 
^ Creek. 155 

Calcium chlorate, deteaion and 
determination of, 236 
chromite, neutral crystalline, 

370 
strontium, and barium salts, 
analjTtical charaaer of a 
mixture of, 37 
cyanate, 197 
Calmette, A., treatment of the 
bites of venomous serpents, 
30 
Cambier, R., and A. Brochet, 
hexamethyienetetramine, X07 
preparation of mocomethyl- 
amine, 198 
*< Cambridge Natural Science 

Series" (review^, x6o 
Cambridge University, X13 
Camphoric acid, constitution of, 

187 
Camphors, bromo-nitro-, iso- 
meric, 314 
Campredon, L., determination of 
sulphur in cast metal, &C., 
X3 
Campolo, I., easence of berga- 
mot, 303 
Candle flame burnt, respirability 

of air in which, 177 
** Candles and Soap, Manufac- 
ture " (review), 368 
Cane-sugar, citric acid from, xoo 
*'Cape of Good Hope, Depart- 
ment of Agriculture" (re- 
viewj. 83 
Carbide, glndnum, 209, 243 
Carbon and argon, speamm of 
Ramsay's ^impound, 99 
atomic weight of, 164 
black, a specimen, \^ 
dioxide, precipitation and de- 
termination, 1^4 
in iron, determination of, 83, 

293 
monoxide, evolntion of, 288 
sulphide, aaion of heat on, 293 
Carbonic add, propertiea 01 so- 
lid, 49 



Carbons of the elearic fnmace, 
I spearoscopic study, 9 
Cardiff University College, xi6 
Carnot, A., ceruin deposita of 

aluminium and potassium 

phosphate, 73 
determination of small quanti- 
ties of arsenic 91 
Carpenter, W. L., and H. Leaak* 

'* Manufaaure of Soap and 

Candlea" (review). a6x 
Carr, F. H., and W. R. DnnaUn, 

constitution of paeadacooi- 

tine, 39 

dibenxaconine, 279 
note on piperovatine, 378 
Caat metal, desnlphuratioo, 3x7 
metals, Ac., determination of 

sulphur in, X3 
Catholic Univeraity, Doblin, xaS 
Cavallter, J., phosphoric elhon 

of allylic alcohol, fix 
Caxeneuve, P., ateriiiaatioa of 

milk, 183 
Cellulose, fermentation of, 369 
Chapman, A.C., derivatives of 

bumulene, ^ 
Charpy, G.. alloys of copper and 

xtnc, 308 
Charterhouse Sdence and Art 

Schools, and Literary Inati- 

tute, X30 
Chattaway, F. D., and H. Insrle, 

new series of hydraxines, 3ft! 
Cbay root, colouring matter 01, 

Chemical balance, new form, xfi 

education, 269, 292 

elements, systematic arrangie* 
ment of, ft) 

equivalents, 343 

history of thebarley plant, 307 

laboratory of Wiesbaaen, 149 

literature, report of committee 
on indexing, xofi 

physical, anatechnlcal calcola* 
tioos, reform in, 7, xoi, X35 

researches and spearoacopic 
studies, vn, 188, 203, 3x3, 
226, 239i 348, 339. 374i 284f 

„30i,3«x 

Seaion of the British Associ- 
ation, Addreu, 141, 131 

Society, 43, 36, 203. 264, 377, 
ao8, 3EX 
of Bdioborgh University, 304 

tradea and drugs exhibition, 
83, 136 * 

** Chemical Analysis, Quantita- 
tive " f review), 320 
'* Chemical Indttsti7 " (reviewX 

** Chemical Laws, Pnakal 

Proof of »» (review), 333 
** Chemical Technics, Mecban- 

ical Anxiliariea '* (review), 30 
" Chemical Woraa, Dangers to 

Men employed in " (review), 

197 
Chemistry and phannacy, 

schools of, X23, 130 

Institute o^ 30 

Liverpool College of, jao 

of tiuninm, critical atudiea on. 

138 
of the cyanide process, report 

of experiments, 60, 93 
of the lignocelluloses, x6 
schools of, xxs 
" Chemistry, Analytical " (re- 
view), 184 
'< Chemistry, Analytical, Specific 
Foundations of" (review), 
333 
*■ Chemistry, Applied, How shall 
Young Men be Edncated in '* 
(review), 60 
**Chemiatry. Elementary, Hints 
on Teaching, in Schools and 
Science Clasaes" (review), 
290 
<* Chemistry, Elements oi Mo- 
dern " (review), 196 
*< Chemistry, lodosuial Organic** 

(review), 200 
'* Chemistry, John Dalton and 
the Rise of Modam'* (re- 
view), 2X 



Jsn. 10, 1896. 



INDBX. — SUPPLBMENT tO THE CBBUIOAL NBWS. 



301 



** CheiDittry, Labontoiy MadhaI 

of Orgaoie ** (review). 310 
'* ChemntfT, Manoftl of Anaiy* 

tIcaJ *• (review), 208 
" Cheroittry, Orftoic and loor^ 

ganic"(reTiew)y36 
** Chemiitry, Pradical and Qua- 

litative Aoalytia" (review), 

at 
** Cbemistiy, Year* Book o( Or- 

CAoic " (review), 61 
•• Chemistry of Nntrition " (re- 

view;, 855 
•• Chemiitrx of Urine " (review), 

«• Chemista and their Wonders " 

(review), 48 
Chikashig6, M., mercnry per- 

chlorates, 354 
Chlorate ol calcinm, determioa- 

tion of, 236 
Chloride, aftfon of dry hydrogen, 
293 
cotnpoanda of ferroai, 97 
of sioc« a^ioD of, 6x 
Chlorides of gold, 56 
Chloro-camphoric add, 3x6 
Chromatea of rare eartha, 69 

of thorium, 69 
Chromic hjrdrate, molecular 

transformations of, xa 
Chromium amalgam, 3x7 

chloride* solutions of i;reen, 138 
Cirencester, Royal Agricnltoral 

Colie^, xx8 
Citric acid, formation of, 31, 165, 
i90,«35,a57iaM 
from caoe->^sagar, xoo 
City and Guilds of London, 62, 

'* City and Ouilds of London In- 

atitnte, Report " (review), 13 
Clarke. P. W., report of com- 
mittee 00 atomic weights, 
_ 93. 105, 157. X67. 179 ^ 
Claases, leAnres, and laboratory 

htatruftion, xas 
Clay filters^ and their nse in la* 

boratones, 86 
Clennell, J. B., estimation of 

simple cyanides, 227 
Clemens, C. P., and P. A. Gooch, 

determination of selenioas 

acid, ai6 
Cl^eitc, constituents of the gas 

in, i8x 
ape^rom of gas from, 2G7 
Clifton laboratorv, xt6 
Cloedc, E., and P. Jannaach, 

quantitative separation of 

meuls, 64 
Clowea, P., composition of the 

limiting explosive miaturea 

of various co mbus tible gases, 

aS8 
evolution of carbon monoiide, 

268 
respirability of air in which a 

candle flame has burnt, X77 
** Pra^cal Chemistry and 

Qualiutive Analyaia " re 

view), ax 

and J. B. Goleman, "Quanti- 
tative Chemical Analysis" 
(review), 220 
Cobalt and biamuth, aeparation, 

9> 
and nickel, atomk weight of, 

Biliade8,28x 

*' Cobalt, Determination of the 
Atomic Weight" (review), 
a33 

Cobra, immunity against the 
poison of, xa 

Cocaine, hydrochlorate, melting- 
point o^ 25 

Cohen, J. B., and W. H. Arch- 
deacon, preparing cyanurie 

and H. R. Hint, modiicstioo 
ot Ziocke's reason, 57 
prmaring the formyl deriva- 
tives of the aromatic 
amines, 57 
Cohn, L., and A. Smith, " Ma- 
nual of Organic Ohemiatiy " 
(revinw), «ao 



Colbum, L. C. and B. E. Slos- 
son, <* University of Wyo- 
ming*' (review), 60 

Coleman, J. B., and P. Clowes, 
** Quantitative Chemical 
Analvsis " (review). 220 

College, King's, free leaure, 276 
of Science for Ireland, Royal, 

134 

of Surgeons in Ireland, Royal, 

126 
Collegea and universities, itt 
Collie, J. If., M. Travers, and W. 

Ramsay, helium, 47 
*' Colliery Exploaiona, Origin and 

Rationale of*' (review), 355 
Colouring matter, imw, 57 

of chay root, 57 
Colours, physical theory of the 

perceptioni X03 
Colson, A., formula of M. Guye, 

49 
Cork, Queen's College, xa4 
Coniin and nicotin, distinction 

between, 73 
" C'Ontistence - Meter" (review), 

Cooper, W. J., and J. A. Wank- 
lyn, nature and composition 
of the commercial Russian 
kerosene, 7 

obaervstioos with a tensio- 
meter, 199 
Cope, P , and A. G* Parkin, con- 
atitueots of Artocarpus inte- 
grifolia, 253 
Copper and ainc, alloy a of, ao8 
ferrocyanides, crystalline, 293 
matte and copper, gold and 
silver in, 76 
** Copper Smelting, Modem " 
(review), 316 
wet assay for, 70 
Cornish. Y., " Praaical Proofs 
ot Chemical Laws" (review), 
233 
Cotton-oil, sulphuretted sub- 
stance in, 209 
"Craft Instrnaion" (review), 

29X 
Crompton, H., relation between 
valence and atomic volume,9 
Crookea, W., apeara of argon, 
66 
apearum of helium, 87 
of Ramsay's compound of 

argon and carbon, 99 
and J. Dewar, London water 
supply, 41, 92, 148, 205,363 
Crookes, W., ''Genesis of the 

Elements " (review), xyx 
Cross, C. P., and 0. Smith, che- 
mical hiatory of the barley 
plant, 307 
Crionydrates, xxo 
Cnndall, J. T., dissociation of 

liquid nitrogen peroxide, 56 
Cursor, radial, 2x9 
Cyanacetio ether, synthesis by 

means of, 193 
Cyanate of cakium, X97 
Cyanide mercury compounds, x6i 
process, report of experiments 

on the chemistry, 80, 95 
solutions, technical axulysis of, 
386,398 
Cyanides, estimation of simple, 

227 

proouaion of, 40 
Cyanurates, formation of sodium 

and potassium, i6x 
Cyanurio acid, preparing, 57 



r\AHL, O. W., and W. C. 

'^ Hancock, chemiatry of the 
lignocellnlosee, x6 

"Dairy Commissioner of the 
State of New Jersey " (re- 
view), 109 

*' Dalton, John, and the Rise of 
Modem Chemistry" (review) 

2X 

Darling. C, R., and J. Young, 
method of transferring gases 
to vacuum tuoes, 39 

Daraens, Q.» pfaysisal theory of 
the perception of colours, xq3 



Dastre, A^ and N. Ploresco, li- 

Suefaaion of gelatin, 345 
oisbaudran, M. L., an ele- 
ment probably new in tcr- 
bias, 392 

DoBrujm, 0. A. L., hydraain 
hydrate, 165 

Do Gramont, A., direa spearum 
snalysis of minerals, 103 

De Koninck, L. L., and E. Ni- 
houl, determination of aul- 

fihor, 3x8 
ey, R.M., helium and argon, 
their placea among the ele- 
ments, 397 

De la Source, L. M., reaaiona of 
tartaric acid, 306 

Delaite, J., " Continuity of the 
CoUigative Properties, and 
the Polymerisation of Mat- 
ter through its Three Con- 
ditions " (review), 184 

Delepine, M.« hexamethylamine, 
X85 

Deligny, M., and 0. Matignon. 
nitro-substitutions, 172 

"Designs, Law of Copyright" 
(review), 23 

Desiandros, H., compariaon be- 
tween the epeara of the gas 
oi Cliveite and the solar at- 
mosphere, 14 
discovery of a third permanent 
radiation of the solar atmo- 
sphere in the gaa of clAveite, 

12 

spearal researchea on the atar 

Altair, 269 
apearoecopic study of the car- 
bons of the elearic furnace, 9 

Desprex, A., new synthesis of 
some aromatic nitriles, 334 

Dewar, J., and W. Crookes, Loo- 
don water aupply, 41, 92, 
X48. 205, 262 
and M. Liveiag. absorption 
spear a of liquefied air, 65 
refraaion and diaperaioa of 
liquid oxygen, X54 

Diamonds, x86 

Diastase on starch, aaion of, 45 

Dibenaacooine, 279 

Oihromocamphor derivatives, 3x4 

Dichlorocoloenes, six, 58 

Diphenylanthrone, 6x 

Diphenyloxyiriaxoline, ayntheais 
of, 278 

'* Disioteaion and DisinfedUnts. 
lotroduaion to the fikody'^ 
(review). 107, X49, x6o 

** Distillery" (teview), 3x6 

Disulpbonic acids of toioene, 58 

Divers, E., and T. Haga, sodium 
niCrososulpbate, 266 

Dixon, A. B., acedylthiocarbi- 
roidea,^7 

Dreverboff, M., filtar-papera, 174 

** Drop, Splaah of " (review), 344 

Droasbach, G. P., periodical 
fluauations of the intenaity 
ol the Earth's gravity, 98 

Drag and chemical tradea axhi- 
bition, 85, 136 

" Drugs and Foods, Aids to the 
Analysis of " (review;, 344 

Dublin catholic Universaty, X36 
University, xx3 

Dutau, fi., neutral crystalline 
calcium chronite, 376 
and G. Patem. combinations of 
antipyrin with the diphenols, 

321 

DuUn, R«.S., wet aasay for Gop« 

per, 70 
Dundee, University College, X32 
Dunstan, W. R., and P. H. Carr, 
conatiiution of pseudaoonitine, 

dibenxacoome, 279 
note 00 piperovatine, 378 
Dunvilher, E^ propionic ethyl- 

hydantoine, 105 
Dupasquier, M., and H. Jay, de- 
termination of boric acid, 166 
Duponc, J., aulpburetted sub- 

sunce in cotton oil, 309 
Durham College of Science, lao 



P ARTH-AIR currents, raatat- 
'^ ance of vertical , 304 
Earth's gravity, periodical fluctu- 
ations of the intensity of» 98 
Earths, rare chromates of, 69 
Ebert, R., new syphon, 35 
Eder, J. M., and B. Valent%red 

spearum of argon, 389 
Edinburgh University, 133 

Chemical Society, t04 
Edmunds, L., T. M. Stevens, 
and M. W. Slade, " Law of 
Copyright in Designs " (tf 
view), 32 
Elearic current as a source of 
beat, use ai, 946 
furnace, 13 

spearoscopic study of the 
carbons of, 9 
Elearical propertieaof salaniom, 

30 
" Blearo-Chemistry, Year-book 

of "(review), 32 
Blearo-magnetic effea, 30 
" Elearolyaia and Solution" <ro- 

view), x6o 
Elearolyaia, general arrange- 
ments for, 346 
quantitative analysis by, aoo 
Elements, boiling point and 
genesis of, 399 
genesis of, 330, 337. 399 
new grouping of, X36 
separatiob of arsenic from 

other, 191 
systematic arranfemsat of the 
chemical, 89 
" Elementa, (veoeais of " (re- 
view), 17X 
Eliaaite, gaaes from the miMral 

283 
Emerald, analyaia of, 345 
Bngel, R., aaion of hydrochloric 

acid on copper, 331 
Ergot in bran, deteaion of, xo6 
Ether and ethyl to alcohol, osmo- 
tic p hen o m e na produced be- 
tween, 97 
cyanacetic, ayntheata by oMans 
of, X93 
Ethers, phosphoric, of nltoltc 

alcohol, 6x 
Ethereal aalta of ethanetotoi- 

carboxylic acid, 48 
Ethylamine, preparation of, 185 
Ethylene dihydroxylamine de- 

bydrobromida, 334 
Kthylhydantoine, propiopic, xOf 
Eogenol, constitution of, 292 
Everett, W. H., magaetic field 
of any cylmdneal ooil or 
plane circuit, 343 
Examinational system, 154 
Examining, the scieoce ot, 103 
Exhibition, Beat London. siiT 
Exploatan, an— aa a warning, 38 
Explosive compositions, mauhes 

with, x6o 
*' Explosives, Manufaaure of" 
(review), 35 



PAHRION, W., deteruHnatipn 

'*> of Hubl'a iodine number, 85 

Pairbanks, Charlotte, and P. A., 
Gooch, estimation of the 
halogena in mixed ailver 
ealts, 217 

Patty acida, aeparation ol vidn- 
tile,37 
aubstances* analyaia of, 209 

Faure, C, calcium cyanate, 197 

Fehling-Soxhlet method lor de- 
termining inverted sugar, 
influence of lead aoetatea on, 
x86 

Penton, H. J. H., formation of a 
new organic acid, 164 
new formation of glycoUicalde- 

hyd. 47 
transformation of ammonium 
emanate into urea, 46 

Fit€e, J., chromium amalgam, 

-, 317 

Ferric chloride And oxalic aeid, 
expcrimeata with mixtures. 
SX7 



322 



INDEX. — SUPPLBMENT TO THE CHEMICAL NEWS. 



Jao. to» i8g6« 



FerrDCsrmnldet, crytUUtoe cop- 

^ per, 293 

PerroM chloride, componndi of, 

«.. 57 

Filter papert, 174 

Filtera, day, aod their ate in 

laboratorief , 86 
Firth College, Sheffield, 12a 
Flame temperatnrea, 76% 
Flax, rettiog of, 293 
Floreico, N., and A. Dattre, 

liqoefaAion of gelatin, 34s 
FlGgge, M., hygienic decision on 

pouble and houtehold waters, 

aio 
Foerster, F., determinatioo of 

carbon in itoo, 293 \ 

'* Food Adalteration, Simple 

Methods for Deteaing" (re- 
view), 290 
*' Foods aod Drugs, Aids to the 

Analysis" (review), 244 . 
Formaldehyd, some readtions of, 

Formic and acetic acids, specific 
heau of superfnserd, 9s 

Forster, M. O., derivates from 
dibromo-camphor, 314 

Fowler, G. J., and H. A. Anden, 
aAion of nitric oxide on cer- 
tain salts, 163 .. , . , 

** Franklin Institute*' (review), 
29X 

Francois, M., aaion of aniline, 

aaion of phenol, 306 

Fraser, T. R., immunity against 
the poison of the cobra, 12 

Fremont, 0., special microscope 
for the observation of opaque 
bodies, 160 

Fresenius, R., deteaioo and de- 
termination of calcium chlor- 
ate, 236 . . * 
and E. Hints, determination of 
uranium, 206 

Friedel, C, valeric aldehyd, 49 

Friedheim, C, aod P. Michaelis, 
sepsration of arsenic from 
other elements, 100 

Friedland*s pneumo-bacillus. fer- 
mentation induced by, 281 
FunaiODS, development of 
arbitrary, 219 

GALENA, qnantiutive nalysis 
of, 78 
Galton, D., presidential address 
to the British Association, 

X37t 139 
Galway, Queen's College, 124 
Gantter, r., recognition of blood 

Gardner,']. A., and J. E. Marsh, 
researches on the terpenes, 

Gascard, A., examination of seed 

lac, 63 
Gas from d^veite, spcarum of, 

from uranintte, new, 4 
in d^veits, constituents of, i8x 
of dAveite and the solar atmo- 
sphere, comparison of be- 
tween, 14 , u J- ^ 
Oases, apparatus for the direA 
determination of the weight 
aod volume, 25 
composition of the limiting ex- 
plosive mixtures of various 
combustible, 288 
from mineral waters, examina- 
tion of, 295 ,. . 
the mineral ehasite, 283 
nraninite, 271 .. . - 

to vacuum tubes, method of 
transferring, 39 
Gaseous bodies, double transpo- 
sition of, 221 
Gelatino-bromide plates, sensit- 
ising aaion of dyes on, 187 
Gelatin, liquefaaion of, 243 
Genesis of the elements, 230,237, 

boiling point and, 299 
•* Genesis ot the Elements'* (re- 
view), 171 



Georges, M., alum in wines, 209 

German Association of Natural- 
ists and Physidans, 73, 73 

Germany, responsibilities of 
manufaaurers in, 98 

Gladstone, J. H., place ot helium 
in the classification of ele- 
ments, 303 

Glasgow University, 126 
and West of Scotland Techni- 
cal College, 123 

Glass cloth for acid filtering, 306 
tbe expansion of, 269 

Glazebiook, R. T., " Physical 
Series" (review), x6o 

Glendinning, T. A., estimation of 
maltose, 234 

Glucina, mordant of, 186 
tioaorial properties of, 198 

Glucinum, 3x0 
carbide, 209, 243 
salts, purification (rf, 77 

Glucose, molecular modifications 
of, 234 

Glycerin as a heating liquid, use 
of 37 

Glycoilic aldehyd, new formation 
of. 47 

Gold and silver, freexing points 
of, 234 
from iron and steel, separa- 

ration of, too 
in copper, 76 

chloride, aissodationof, 48 
chlorides of, 36 

Goldsmith's Institute, 123 

Gooch, F. A., and C. F. Clemens, 
determination of selenious 
acid, 216 
and Charlotte Fairbanks, esti- 
mation of the halogens in 
mixed silver salts, 217 
and I. K. Phelps, determination 
and precipitation of carbon 
dioxide, 194 
and W. G. Reynolds, reduaion 
of the scids of selenium by 
hydiiodic acid, 136 

** Goods, Handling Dangerous" 
(review), 280 

Goyder, G. A , report of experi- 
ments on the chemistry of 
the cvanide process, 80. 95 

Graebe, H., examination of blood 
pigment, 9 

Grapes, aaion of air on the must 
of, 49 f 

Graphite, study of, 333 
of varieties. 229, 233 

Gravity, earth's periodical fluau- 
ations of the intensity of, 98 

Green chromium chloride, solu- 
tions of, 138 

Greene, W. H.. H. F. Keller, 
and C. A. Wuru, " Elements 
of Modem Chemistry" (re- 
view), 196 

G reeves. A., and W. P. Wynne, 
six dichlorotoluenes, 38 

Gregory, R. A.. " Exercise Book 
of Elementary Praaical Phy- 
sics" (review), 291 

Gr6hant, M., toxicity of acetyl- 
ene, 233 

Griffiths, A. B., and C. Piatt, 

composition of pelageine, 183 

E. H., and Miss D. Marshall, 

latent heat of evaporation of 

beoxene, 243 

Grimaux, C, para-ethoxyquino- 
leine, 306 
C, aaion of zinc chloride, fix 

Grimbert, L.. fermenutions 
induced by Priedland's 
pneumo-bacillus, 28X 

Gnichard, M. P., ** Distillery" 
(review), 3x6 

Guilds of London and City, 62, 
123, X73 

** Guilds 01 London and City, 
Report of Institute** (review), 
23 

Guillot, M., and M. Massol, spe- 
cific heats of superfustd for- 
mic and acetic acios, 98 

Gum of wines, 161 

Outtmann, O., ** Manufaaure of 
Explosives" (review), 33 



Gnye, M., a formula of, 49 
Goyot, A., and A. Halfer, di- 
phenyl anthrone, fix 



H' 



AG A, T., and E. Divers. 

sodium nitrososulphate, 26(> 

Haller, A., ** L'Industne Chim- 

ique" (review), 84 

oxidation produas of benzyli- 

den csmpbor, fix 
and A. Guyot, diphenyl an- 
throne, fix 
Hallopeau, L. A., add ammonium 
sodium tungstates, X2 
paratungstic acid, fix 
Halogens, estimation of, 2x7 
Halpnen, G.. analysis of fatty 

substances, 209 
Hambly. P. J., and J. Walker, 
transformation of ammonium 
cyanate into urea, 46 
Hampe, W., determination of 
sulphur in commercial lead, 

35 
Hanamann, J., determination of 

phosphoric acid, 29 
Hancock, W. C, and C. W. 
Dahl, chemistry of the ligoo- 
cellulosei, x6 
Hand-damp, universal form of, 

287 
Hansseo, C. J., reform in chemi- 
cal, physical, and technical 
calculations, 7, tot, X36 
Harrop. H. fi.. and L. A. Wallis, 
'• Forces oi Nature" (review), 
220 
Hart, E., purification of glucinum 

salts, 77 
Hartley, W. N., inadequacy of 
aids and fadlities for scien- 
tific research, 256 
Helium, 27, 47, 239 
atomic weight of, 239 
in monaxite, 32 

place in the classification of 
elementary snbstsnces, 291, 
305. 317 
spearum, 9i7 
and argon, 89, 297 
combination of magnesium 

with, 133 
discussion 00,223 
expsntion of, 293 
in certain mineral waters, 132 
in natural nitrogen, 310 
in the gases from sulphurous 

springs, 309 
refraaion and viscosity of, 
132 
Henderson, G. G.. and D. Pren- 
tice, aaion of certain acidic 
oxides, 266 
Henry, L., glucinum carbide, 243 
synthetic formation of mixed 
alcohols. 98 
Henselin, M.. snd M. Rietsch, 

apiculated fermentation, xfix 
Heut, G., distinaion between 

coniin and nicotin, 73 
Heriot-Watt College, 123 
Hermes Trismegistus, the latest 

disciple of, X99 
Herxig, J., and H. Meyer, detec- 
uon of aikyl combined with 
nitrogen, 37 
Hetse, O., melting point of coca- 
ine hydrochlorate, 23 
Heycock, C. T., and F. H. Ne- 
ville, freexing points of silver 
and gold, 234 
Hexachlorobenxene parachloride, 

X73 
Hexamethylamioe, X83 
Hexamethylenetetramine, 107 
Hexametbyltriamidotriphenyl - 
methan, ammoniated deriva- 
tives of, 198 
Hexane, normal, 277 
Hexylene and hexyl* hydride from 

mannite, 73 
Hicks, £. F., formation of citric 
acid by the oxidation of cane 
sugar, 163 
Hill, R. W., fuming sulphuric 
add, 73 



HiUebrand, W. P„ claverita from 
Cripple Creek, 133 
warning against tbe use of flu- 
oriferous hydrogen peroxide 
in estimating titanium, 138 

Hinu, E., and R. Fresenius, de- 
termination of uranium, 206 

Hirst. H. R., aod J. B. Cohen, 
modification of Zincke's re- 
aaion, 37 

preparing the formyl deriva- 
tivea of the aromatic amiuM, 

Hodgkins prixe award, 8fi 

Hodgkinson, W. R., leaure ap* 
paratus, x8o 

Hofmeister, P.. determination of 
uric acid. 40 

Holmes, P. M., ** Chemisu and 
their Wonders" (review), 48 

Horton, W. A., and P. T. Aus- 
ten, convenient form of uni- 
verssl hand-clamp, 287 

Hiibrs iodine number, determin* 
ation of, 83 

Hubert, A., and O. Riviire, gum 
of wines, xfix 

Hoggins, W., helium, 27 

Hughes, J., determination oc 
water in sulphate of ammo- 
nia, fi 

Hngot, C, alkaline phosphides, 
98 

Hummel, J. J., and A. G. Perkio, 
colouring and other constitu- 
ents of cosy root, 37 

Humulene derivatives, 47 

Hunt, H. P., and J. Perry, de- 
velopment of arbitrary func- 
tions, 219 

Hydras in hydrate, 10$ 
and its salts, quantitative de- 
termination of, 79 

Hydraxines, new aeries, 2fi« 

Hydrste, molecular transforma- 
tion of chromic, xs 

Hydric sulphide, &c, qnaliutive 
anal^s of a solution con- 
taining, 63 

Hydrochloric add, aaion of,a2X 
dry, 126 

Hydrofluoric acid, aaion of, 278 

Hydrogen and oxygen, occlusion 
of, 3 
chloride, aaion of dry, 293 
peroxide, 28x 

Hydroxylamine, deteaion of^ 238 

Hypooitric anhydride, aaion of, 
98 

Hygienic decision on potable and 
household waters, 210 

IMPERIAL Academy of Scien- 

*■ ces of Vienns, 289 

Indexing chemical literature, re- 
port of committee, xo6 

Infra-red rays, aaion on silver 
sulphiae, 80 

Ingle, H., and F. D. Cbattavay, 
new series of hydrazines, 263 

Ink, new black, 203 

Inorganic compounds, 22t 

'* Inorganic Preparations, Labor- 
atory Manual of" (review), 
280 

Institute, Battersea Polytechnic, 
150 
of Chemistry, 30 

"Institute, Franklin*' (review), 
29X 

Institution, Royal, 23, 234* ^t 

, 272, 281 

Invert sugar, experiments with, 
236 

Iodic acid in nitric acid, deteaion 

<rf.37 
Iodides, aaion of light 00 soluble 

metallic, 173 
Iodine in urine, deteaion of, 24 
number, determination of 
Hiibrs, 83 
Iridium compounds, xa 
Iron, determination of carbon, 83, 
*93 . 
estimation of sulphur 10, 299 
oxides of reduaion, ail 
and steel, sepsration of gold 
and silver from, xoo 



Jafl. Kf 189^ 



INDBX. — SUPPLEMENT TO THE CHEMICAL NEWS. 



323 



IwiMltow of C. J. Lintoor, 4s 
lMT»leric aldsbyd, coodeatatioD 
prodoa*, 98 

J AGO, W., " Tcxt-book of the 
Science aad Art of Bread- 
naktncl* (rertew), 72 
JanDaach, P., opening ap aili- 
caiee, 51 . . 

and E. Clocdt, qaaotitative 

•ecaratioo of meuU, 64 
and H. IUoimerer,qa«ntitative 
analyait of galena, 78 
qoandutive aeparatlon of 
metalt, ot 

J., law of abtOTption 



of the bands of the tpe^rum 

ofoiTfen, II 
Japp, F. K., and O. D. Lander, 

coadenaactoo of beoxil, 56 
Jarry, R., and P. Villard. proper- 

tiea of solid carbonic acid, 49 
Jansaeo. J„ researches daring a 

jooroey np Mont Blanc, 108 
Jajr, Hm ▼olatile acidity of winest 

909 
and If . Dupaaqoier, determina- 

tioo ot boric acid, 166 
Jaan, P^ preparation of ethyl- 

amine, 183 
jcffrc, J ^ nae of aoperphospbates, 

JohoTV.. and E. P. Ptrmtn, 
borax and standard acid sola- 
tioos, 84 

Jolles, A., deteaion of iodine in 
urine, 24 / 

Joly, A., and B. Lddy, com- 
pounds of iridiom, la 

Jooes. A. W., molecular volnme 
change during the formation 
of dilute solntioos in organic 

Men Bmployedin Chemical 
Works ''(review). 197 
Jari«:h. K. W. B.,"kanttfae. 
tore of Alommiom Sulphate" 
(review), 83 

ITAMMERBR. H.,and P.Jan- 
A^ ouch, quantiutive analysis 
of galena, 78 
qoantiwtivc separation of 
metaU, 9« ^ , 

Kayscr, H.. bloe spearum of 
argon, 99 
helium and argon, 89 
Rellai, A^ pttceatage of argon 
in air, foB 
uod W. Ramaay, csaminatioa 
of gases from certain mineral 
watera,a9S 
Keller, H. F.,7:. A. WnrL 
W. H.Grcsne,- 
Modern Chemi' 
196 
Kehnan, W. 

volumsjJf-igSmatioo 
phoa^;Kacid,t8 
K«™t^^ forging iet crucible 
iUel ingou for tool maao* 
, V fidore. 5 
^' «fia nature and compoai- 



)( of 



oommcreial RuMiao.y 

*ii,ncw, t4S 

Ida, aAioo of asym* 

, xio 

•99, US 

ture,a76 

'. S., derivativea ol 

camphoric acid, 313 
Lapwonb, isomeric* 

•nitro camphors, 314 

). Pope, chloro-cam- 

i acid. 316 

, ayntneaia by means ol 

cetK ether, 19a 

., new speiAral photo- 

:.a36 

L., coodcosatioD>pro- 

t Qi iaoraleric aldehyd, 

D. A., qoantiutive de- 
daatioo of p«rchloraCea» 



Krewtaoff, M.. desolphuration of 
cast metal, 3x7 

Kmpp and Ca, apparataa for tho 
direa determination of the 
weight and volume of gaaea, 

2S 

Krfiss, G., the late Professor. 293 
and O. Unger, heavy metalUc 
salts of bichroroic acid, aSz 

Kuenen, J. P., and W. W. Ran- 
dall, expansion of argon and 
helium, 293 

•• Karze*a Handboch der Kohlen- 
hydrate " (review), 206 

Kyle, J. M., Braailian monaxite, 
t4 



LABORATORY, Uanres. 

classes, and inatruaion, 
125 
Laccaae in plants, 73 

oxidising power of, IIO 
Laaones, 49 

Lamp, new safety paraffin, 174 
Lanchester, F. W., radial cursor, 

axq 
Lander, G. D., and F. R, Japp 

condensation of benxil, 56 
Langlet, N. A., atomic weight of 

taeiiuro, 259 
Lapworth, A., and P. S. Kipping, 
iaomeric bromO'oitro-cam- 
phora, 314 
Lead aceute, influence on the de- 
termination of inverted sugar, 
186 
commercial, determination of 

aolphur in. 35 
and mercury, separation of, 65 
Leask, H , and W. L. Carpenter. 
" Manufaaore of Soap and 
Candlea '* (review). 268 
Lebeau, P., analyaia of emerald, 

glucinum carbide, 209 
Leaure apparatus, 180 
Leaures, classes, and laboratory 

instruaion, 123 
Lee, T. H.. some reaaiona of 

formaldehyd, 133 
Leffimann, H» ** Examination^ 

Water lor Sanitar 

Technical Fnrpos] 

view), 221 
Lcidy, fi., and 

pounda of i 
Lcmoine, G^^^^^pBta with 

mi itm^^^^^Bbchloride 

and 

of ao- 
potaasinm cyan- 

H., volumetric deur- 
:ion of metals, 66 
ng milk, ito 
ite baaalt, recent analyses, 

Lcvoir, L O., gradation in 

pressures, lox 
•• Life and Labour of the Peopla 

in London *' (review), 81 
Light, aaion on aoluble metallic 

iodidea,i73 ^ . . ^ 

Lignocelluloses, chemistry of. 16 
Linalde, essence of, 73 
Linebarger, C. B^ vapour un- 

siobs of mixtures of volatite 

hqatds, 167, 182. 196, axa, 

a3t. tJ?, 250, x6« 
Ling, A. R., and J. L. Baker, 

aaion of dustase 00 starch, 

Untner, C. J., the isomaltoae of, 

43 
Liquid, nae of glvcarin aa a 

heating, 37 
Liqaida, comparing the heats of 
evaporation of different, a43 
of tna organiam, constancy of 
the congeUuon point of 
some, a8t 
Tolaule, vapour-tensiooa of 
mixtntea of, 167, 182, 1981 
212,231.238,230,263 
Lithium, thermo- chemical r*- 
I •aarcbMoa,S4S 



Liveiog. M., and J. Dewar, ab- 
aorption speara ot liquefied 
air, 63 

refraaiou and dispersion of 
liquid oxvgen, 1^4 
Liverpool College 01 Chemistry, 
120 
University Colleice, xto 
Lockyer, J. N., gases from the 
mineral eliasite, 283 
new gas from Qraainite,4, 271 
London Bxhibition, East, 318 
University, lit 

water aupply, 41, 9a, 148, J05, 
262 
Long, J. H., phenomena ob- 
aerved in the precipitation of 
antimony^a, 43* S3 ^ 
Longuiaine, w., latent heata of 
evaporation of the acetonea 
of the fatty series. &c. . 233 
Loof, M., deteaion of iodic acid 

in nitric add, 37 
Luminescence, illumination by, 

X04 
Lnxmoore, C. M.. ethylene di- 
hyorosylamine dihydrobro- 
mide, 234 
isomerism of poiaasiom ni- 

trososulphate, 234 
oximes of benxaldebyd, 37 



Vf ACDONALD, M , conaUta- 
^^* tion of pyraxole, 304 
Maclunn, derivatives of, 233 
McGowan. G., and W. Ostwald. 

** Specific Poundations of 

Analytical Chemistry** (re- 
view), 232 
Magentas, acid, 198 

are they ethers or salts 7 173 
Magnesium, combination 

argon and helium, i\ai 
Magnetic field of an^^gHRcal 

coil or plane^^^l^ 
Malbot, H. a^^^MHaphates 

of Ale^^^^ 
MalluH^^IVl O. Bsrtrand, 
of peaaae, 292 
aeries, 234 

nation. 254 

u, B., tannin in winee, 

269 

Manganese silicide, 308 
and mercury, separation of, 63 
and ailver, aenaratioo of, 91 
Msnnite, hexylene and hexyl- 

hjrdride from, 73 
Mannfaaurers in Germany, 

reaponsibilites of, 99 
Manures, special. 162 
Marchlewski, L.. an . B. Schonck, 

aome derivativaa of aathra< 

qoinone. 289 
Margfoy, M., chemical eqoiva- 

IcnU, 245 _ 

Marsh, J. B., and 1. A. Gardner, 

researches on ihe urpenea, 

Manhall. M.. optical aaivity and 

crrstatline form, 303 _ 
Miss D . snd B. H. Griffiths. 

latent heats of evaporation of 

beoxene, 243 
and Prof. Kamsay, comparing 

the heats of evaporation ol 

different liquids, 243 
Martinand, V., sakm of air 00 

the moat of grapes, 49 
Mason College, Birmi gham, txy 
Maaaol, M., and M. GutHot. 

apecific heata of superfosed 

formic and acetic scids, 98 
Mauhes with explofhrs compoai- 

tioos, 160 
pim^^ 234 
Matignon. C. and M. Detigny, 

oitTO-substitutions. 172 
** Mechanical Auxiliaries of Che- 

nsicnl Technics " (review), 39 
Medicine schools, 116 
Mciatels, K , and W. Kelman, 

voiumetnc estimation of 

pho«phoric aad. s9 
Maldola, R., Addreta to the Che- 
mical Seaioo of th« Britiah 



Meldola. R , and P. W Streat- 
feild, derivativea of naphtha- 
lene, 22(2 
Mendeleefit, D , argon, tx 
** Men Employed in Chemical 
Worka, Dangers to** (review), 
197 
Menschutkin, N., "Analytical 

Chemistry " (review), 184 
Mercaric chloride, hydrolysis of 

the aqueous solutions of, 62 
Mercury, combining beau of, 183, 
209 
cyanide compounds, z6f 
double decompoaition between, 
and alkaline and allcalina* 
earthy meuls, 309 
perchlorates. 2m 
separation of bismuth from, 64 
and lead, separation of, 63 
manganese, separation of, 63 
Messar, J., crystalline copper 

fcrrocyanides, 293 
Metal, desolphuration of cast, 317 
Metallic osides, direa fixation of 

cerUin, 281 
Metala, heavy, determination of, 
212 
quantitative aeparatlon 01^64, 

91 
volumetric determination of, 
166 
Meteoritea, study of, ao8 
Meyer, H.. and J. Herxlg, detec* 
tion of alkyi combined with 
nitrogen, 37 
Michaehs, P., and C Preidhelm, 
seiMiration of arsenic fimn 
other elements, 190 
Microscopo for observing opaque 
6s, t6o 
ipic analysis of carbon- 
steels. Report on paper, i6x 
examination of cruds cement 
steel. 24 
Milk, impurities in, 186 
sterilisation of, 163 
watering, deteaion of, no 
** Milk, its Nature and Composi- 
tion •• (review), 279 
Milla, C new axo-componnda. 

Mineral eliasito, gaaea from, 283 
oil for excluding air in Pavy 

titrations, use of, 11,24 
waters, examination ot gaaea 
from, 293 
Minerala, direa apearum analy 

sis of, 103 
Minnnni, G., and B. von Meyer, 
*• Year-book of Organic Che* 
miatry** (review), ox 
Moissan, H., preparation and 
propertiea ol pure melted 
molybdenum, 2 
reduaion of silica, 49 
specimen of black carbon from 

Braxil, 183 
study of certain meteorites, ao8 
graphite from pegmatite, 233 
varieties of graphite, a29, 233 
Molecular physics, 37 
I transformations of chromic 
\ hydrate, 12 

volume change. 279 

Molybdenum, atomic weight, a8i 

preparati m and propertiee of 

pure melted, 2 

Molybdic acid determination, 293 

Mooaxite, a mineral containing 

helium, 32 
Mond, L., history of Mond*s 
nickel extraaion process, a83 
W. Ramsay, and J. Shielda, 
occlusion of oxygen and hy- 
drogen. 3 
Menu's nickel extraaion proceaa, 

history of, 283 
Mooomethylamine, preparatioo 

of, 198 
Moot Blanc, reeearchea con- 
neaed with an ascent of. ao8 
Moore, C. G.^ and T. H. Pear- 
main, ** Aida to the Anaiysia 
of Foods and Drugs'* (re* 



T., volnmetric aatimatioo of 
Bidml, 9a 



3H 



tKDBX. — SUPPLEMENT TO THE CHEMICAL NEWS. 



I*n. 10, 1896. 



Mordant of glucina, 186 
M5rner, 0. T., examioition of 

butter, 246 
Morphia, novel reaAionaof, 51 
Morria, G. H., and H. T. Brown, 

the iaomaltoae of C. J. 

Lintner, 45 
Movreu. C, argon and heliam in 

natural nitrogen, 310 
conatitntion of eagenol, aos 
Moter. J.," Manoalot Analytical 

Chemittrjr " (review), 208 

NAPHTHALENE derivativta, 

Naphtholanlpbonic idd, 109 

Naphtholi, diatinAion between a 
and 0, 246 

Naaini, R., argon. 347 

Naatnkoff, M.,redodive power of 
yeaat, 214 

Naturaliita And Physicians, Ger- 
man Association, 73, 73 

••Nature, Forces of" (review). 

Ner^, W., "Yearbook of 

Elearo-chemistry" (review), 

22 
Neumann, O., determination of 

heavy metals, 212 
Neostadt, M. S., and H. T. 

Vulte, ** Laboratory Manual 

of Inorganic Preparations '* 

(review), 280 
Newth, G. S , aAion of hydro* 

fluoric acid, 278 : 
nickel and cobalt, atomic weighta 

oi* 40, S2t 109 
rilictdes, 281 
extraAjon process, hist 

Mond's, 283 
volumetric estimation of, 92 
Nicotin and coniin, diatinAion 

between, 73 
Nihool, E.,and L. L. de Koninck, 

determination of sulphur, 318 
Nitrates, basic, Z09 
Nitric oxide, aAion of. 6x, 163 
Nitrites, new synthesis of some 

aromatic, 234 
Nitrogen, argon, and helium io 

natural, 310 
combination of free, xi 
peroxide, aAion of, 233 
diaaociatioQ of liquid, 36 
Nitro-substitutions, 172 
Nitrososulphate, sodium, 266 
Nividre. G., and A. Hubert, gum 

of wines, 161 
Nominations,73 
Nottingham, University College, 

xai 
" Nutrition, Chemistry of " (re* 

view), ass 



rvBITUARY, the late Louia 
^^ Pasteur, 170 
Oftochlorophenoli, three. 183 
Oil, sulphuretted substance in 

cotton, 209 
Omelianski, v., fermenUtion of 

cellulose, 269 
Opaque bodies, microscope for 

observing, 160 
Optical aftivity and crystalline 

form, 303 
Organic acid, formation of a new, 

X64 . 
'* Organic Chemistry, Industrial** 

(review), 290 
•* Organic Chemistry, Laboratory 

Manual of" (review), 220 
" Organic Chemistry, Year*book 

of" (review), 6x 
Organic liquids, molecular volume 

change daring the formation 

of dilute aolutiona in, 279 
Orthobenxoic aulpbinide, 253 
Orton, K. J. P., and S. Rube- 

mann, malonic acid aeries, 

Osmond, P., microscopic analysis 
of carbon steels, report on 
paper by, z6x 
tempering extra hard steels, 
280 



Osmotic phenomena produced 
between ether and ethylic 
alcohol. 97 

Ostwald. W., ** Speciflc Founda- 
tions of Analytical Chemis- 
try •* (review), 232 

Ouvrard, L., and L. Troost, 
argon and helium from the 
gases from sulphurous 
springs, 309 

combination of magnesium 
with argon and helium, tS3 

Owens College, X2o 

Oxmlic add and ferric chloride, 
experiment with mixtnrea, 
317 

Oxford Univeraitv, xx^ 

Oxide, nitric, adifon of, 6x, 163 

Oxides, acidic, aftloo of certain, 
266 
of iron, redodtion of, 2xx 

Oximea of benxaldehyd, 37 

Oxygen, law of absorption of the 

bands of the spectrum, xx 

oxidising properties of oxoolsed, 

6x 
refraftion and dispersion of 

liquid, IS4 
and nydi^ofc^n* occlusion of, $ 

Oxoniaed oxvgen, oxidlaing pro- 
pertiea of, 6x 

Oxotoluene, 269 



pALMBR, C, chromatet of 

^ rare eartha, 69 

Paper, corrugated, And boards for 

packing, 306 
Para-ethoxyquinolelne, 306 
Paraffin lamp, new safety, 174 
" iratungstic add, 6t 
"' H. G.. and T. W. 
occlusion of barium 

Ix 

Parmenfl^^Ko bitominona 




il Aux. 
Tech- 



Parnicke, i 

iliaries of ____ 

nics ** (review), f* 
Paachen, P., and C. Runge, cO^ 

Btituenu of the ga« m 

clAveite, x8x 

spedtrum of new gas from 
cidveite, 266 
Paateur's successors, 267 
Pasteur, the late Louis, X70 
Patein. G., and E. Dufau, com- 
binations of antipyrin with 

the diphenols, 221 
Pateraon, D., efiaoreacence of 

double ferrous aluminium 

sulphate, 289 
Patricroft Higher Grade School, 

X26 
Pavy titrations, use of mineral 

oil for excluding air in, xx, 24 
Pcarmain, T. H., and C. G. 

Moore, " Aids to the Analysis 

of Foods aad Drugs ** (re- 
view), 244 
Pedtase, distribution of, 292 
Pedtose, mysterious disappear- 
ance, 23 
Pegmatite, study of graphite 

from, 235 
Pelageioe, composition of. x8s 
Pennington, Mary E., and E. F. 

Smith, atomic wdght of 

tungsten, 221 
"People in London, Life and 

Labour of " (review), 82 
People's Palace, X2S, 130 
Perchlorates of mercury. 234 
qusntitstive determination of, 

241, 231, 261 
Period-table, 200 
Periodidrs of theobromine, 278 
** Perken, Sor), and Rayment's 

Illustrated Catalogue of 

Photographic Apparatua, 
. Ac." (review), 268 
Perkin, A.G , constituents of the 

root of Polygonium cospida* 

tum, 278 
resorcyiic acid. 233 
and C. S. Bedford, derivatives 

ofmadurin, 233 



A. O. Perkin and K. Cope, con- 
Btituents of Artocarpos inte- 



grirolia,233 
tnd T. J. Hi 
and other constituents oT 



and J. J. Hummel, colouring 



chsy root, 37 
W. H., influence of tempera- 
ture on refradtive power. 288 
Perman, E. P., and W. John, 
burax and standard acid solu- 
tions, 84 
Peroxide of hydrogen, 28x 

of nitrogen, sdtion of, 233 
Perry, J., and H. F. Hunt, de- 
velopment of arbitrary lanc- 
tions, 210 
Peters, B. D., jun., ** Modem 
Copper Smelting** (review), 
316 
Peterson, /., quantitative deter- 
mination oir hydraxin and its 
salts, 79 
" Petroleum** (review), 36 
Petrsilka. H., proteaive capsules 

for platinum crucibles, 83 
** Pharmaceutical Journal of Aua- 

tralasia" (review), X09 
Pharmaceutical Society of Oreat 

Britain, School, 1x3 
Pharmacy, co^tversaxione at the 
Melbourne College of, 234 
schools, 123 
Phelps, J. K, and F. A. Gooch, 
precipitation and determina- 
tion of carbon dioxide, 194 
Phenol, adtion of, 306 
Phillips. H. J., "Handling of 
Dangerous Goods'* (review), 
280 
new form of chemical balance. 
16 
Phipsoo, T. L., cane sugar and 
dtric acid, 237 
citric acid from cane sugar, xoo 
and tartaric acida from cane 
sugar. 190 
Phoaphates, certain depoaits of 
aluminium and potaaaium, 
73 
of Algeria, X72 
Phosphides alkaline, 98 
phosphoric add, volumetric esti- 
mation 01. 28 
g^M of allylic alcohol, 6x 
p^^^^us in steels, rapid de- 

^^^^|ipn of. X7| 
Phd^^^^^^Vtpectral, 236 
•« pQII^^^^BM review), 160 
Phyaioa^MtTv^ ^^9t 342. 
aWf 304 
theory of the perca^ion of 
coloura, 103 
Physicians and Naturalists, Q^r- 

man Association of, 73. 75 
«' Physics, Elementary Pradtical** 

(review), 29X 
Phyics, molecular, 3x7 
Piccini, A., solutions of green 

chromium chloride, 138 
Pigment, new badterial, 82 
Piperonylioene-acetone, iio 
Piper ovatum, note on, 278 
Plants, laccsse in detedionof, 73 
Platinichloride, produAion of 

potassium, 233 
Platinum crucibles, protedtive 
capsules for, 83 
thermometer, diredl reading, 
267 
Piatt, C, and A. B. Griffiths, 

composition of pelageine. X83 
Pneumo-bacillus, Friedland's, 
fermentations induced by, 281 
Poinseo, H. C, ang-kbak, a Chi- 

neae fungoid pigment, X03 
Poisons, new, 174 
••Poiions" (review), 139 
Pollard, W.. and K. Seubert, 
atomic weight of molybde- 
num, 2^1 

determination of molybdic 
acid, 293 
Polygomum cuspidatam,constitu- 

ent of the root of, 278 ■ 
"Polymerisation of Matter 
through its Three Conditions, 
Continuity of the CoUigative 
Properties and** (review), 184 



Polytechnic Institute, ia6 
Battertea, 130 
Polytechnic lonitote of Brook- 
lyn*' (review). 172 
Ponsoi, A , cryohydrstes, no 
rope, w. J.. orihobcMoic rolph- 
inide, 233 
and V 8. Kippiof. chtoro. 
camphonc acid, 316 
Potassa, aaion of, xai 
Potassium, derivstives of qnioooe 
and hydroqaioooe, 160 
oitrosoaulphste, isoraeriaa of, 

platinichloride, prodoftion of. 
*53 

alomiaiam 



certain deposits of, 71 
Pott, E., '* Chemittrjr of Nstri- 

tion*' (review), 255 
Prentice, D., and a G. Header. 

son, aftioo of certsio acidic 

oxides, 266 
Preasures. gradation ia, loz 
Prober, K., bekaviOQr of taaoia 

aubstances, 257 
Propionic ethyl bydaotoioe, 185 
"ProspeAor's Htodbook" (re- 

view), 22 
Prud'homme, M., s qaestion Of 

acid maeentas, X98 
mordant of glocioa, 186 
sulphoDsted coloariog mstten' 

der'ved from tripbenylnetb- 

ane, X09 
tin Aorial propettiesof ftsdoi, 

Pseudacottittae. coostitatios of, 

« 59 

Purdie, T., and H. W. Bolin, 
optically aAive methoxy tod 
propoxr^succiuic sddi, 153 
and S. Williamsoo, laccioic 
acids, 253 

Pyraxole, 304 

Pyrometry, 8$ 

QUANTITATIVB satlFiii ^ 
elearolysis, joo 
'* Quantiutive Cbemicsl Aasl^ 
Bis** (review), 220 
determiostioB of bydraxia sb^ 
its salts, 79 
Queen's College, BeUut, m 
Coik, X24 
Galway, 124 
Quinone and bydroqatoooe, pot- 
assium derivatives of, 160 

P AMSA Y'S conpeoed of irfoa 

^^ and carbon, spedram of, 99 

Ramsay, W., possible oonpoeod 

of argon, 31 

c^if\Mushail. ooopsnar 

the hSMti*^??*** 

diflferent 1^ 
J. N. Colliep 

helium, 47 "^teri 
and A. Keliaas, exa^^ 

gases fronai ccruii?L 

waters, 295 'h 

L. Mond, and /. Sbielda, ^' , 

aiOD of oxygen aad hydrogj 

•°1 ^i f •y'eigh, awar 
Randall, W. W.. and J. p. kI 

nen, expanaioo of arson 

helium, 293 
Rang. F., the period-table, ; 
Raoult, F. M„ oamotic pfavi 

meoa produced betweea et4 

and ethylic al cohol . 07 1 
Rayldgh, Lord, refradtvon J 

viscosity of argon and heHm 

X32 
and W. Ramaay. award of 4 

Hodgkins prixe, S6 
Read, E. J. ,estimation of aulpl 

in iron, 299 
Recoura, A., molecular tranf<»J 

ationa of chromic hyiSrato, 
Red apeArum of argon, aSg 1 
Runge, 0., and F. Pascben, od 

atituenta of the gmm in cl« 

ite, x8x 



Jib. 10, 1896. 



INDBX. — SUPPLBMBNT TO THB QHBMICAL NBWS. 



laS 



Rdnfttve power* inflneoM 

tempentaxe 00, a88 
R«un), A., oxotoluene, 260 
cole 



E. H., Dew coloariag 

(DA^ter, 57 
Rcecucb fond of the Balter'f 

Compeoy, ag^ 
RetUtaoce aod itt cbanfe with 



Reeorcylic acid, m 

Respirator wanted for laboratory 

nee* 50 
Rettinc of flaz» J93 
ReverdiD, P., napbtbokalpbooie 

acid, 109 
Rajrchkr, A^ amniooiacal ialta 

of tUver, 173 
Rvjroolda, W. G., aod P. A. 
Goocb. reduAion of the adda 
of seleoinm by bydriodic acid, 
X56 
Rhodes, If., armatnre readtioa 
OB a aiagle phase altematiag 
cnrreat machioe, ao 
Rices imported into France, 
I conpoaitioo of, 233 

t Richards, T. W.. revitioo of the 

atomic wetcot of atrontinm, 
18, 29, 4X>S4*73 
and H. G« Parlcer, occlusion of 
bariam chloride, aSx 
Richmond, H. D., ••standard" 

acid solntioos, s 
Ridea), S.. diaiofeaants, 149 
** IniroduAion to the Study of 
DisiofeAiOQ and DitiofeA* 
anu** (review), 107, 149 
Riettcb, M., aod M. Heoselin, 

apicnlated fermentation, x6i 
RigoUot, H.. aAiOQ of the infra- 
red rays upon silver solpbide, 
80 
Rivals, M., and D. Berihelnt, 
laaones or campboleoic 
olides, 49 
RobioesQ, K, and O. Rolhn, am- 
monia in atnc powder, 37 
RoUin, O.. and P. Kobioeau, am- 
I monis in sine powder, 37 

Rosanilinea, basic properties of, 

"73 
Roecoe. Sir H. B.. ** John Dslton 
aocl the Rise of Modern 
Cbemitnry*' (review), ai 
Rose. T. K., dissociation of goM 
cnlonde, 48 
some physical properties of 
cblondet of gold, 56 
Roeenleld, M.. sAioo of sodium 

on water, 38 
Roaentticbl, A., ammoniated de- 
rivaiivcs of hesamctbyltri- 
amidotripbenylmetbao, 198 
are the msgeous ethers or 

sahs 7 173 
basic properties of the roaani- 
lines, 173 
Ronaset, L., noo> existence of the 
mixed anhydrides, 110 
piperonylidene acetone, xio 
Royal College of Science, 113 
for Ireland, 124 
ext. Insulation, as, 234, 343, a7<i sSt 

*c«rt»«t ^ Society, 34, a«i, 

Riicker, Prof., resistance of verti- 
I SbidM^ cat earth-air currents, 304 
iatadbrMnhemano, S., aod K J. P. 
Ortoo, malonic aad series, 

^- 96 ..ange. Prof., and M. Paschen, 

from 



spectrum of 
cidveite, tM 



new gaa 



3flof«r|oe 

.^^!U«^ADTLER, 8. P., •* Industrial 



Organic Chemistry" (review). 



^^b^m. Andrew's University, 123 
*^ inlisbary, Lord, remarks on the 

gf^ d t discourse of, on the present 
^* ^ limits of our science, iqt 

'[LgWfSly^aUiowslii, H., determination of 

the thioureas, 83 
.^itrntf^'^tpctrc, discovery at the Cape, 
^to**a* 186 
TL fSf Ahar^ Conpany Reataich Pnnd, 

Psi**S ••* 



Salts of bariam, strontium, and 
caldnm, analytical charafter 
of a mixture, a? 
glucinum, purincatioo, 77 
silver, ammoniacal, 173 
vapour pressure of concen- 
trsted solutions of, aoz 
'* Saoitas ** (review), 160 
Schaak, P., determinatioa of 

aotipyrin, as8 
Schifi; R., preparation of thio- 

acetic aad, 64 
SchloBsio^ T., jun., determina- 
tioa oif argon, ail, a47 
matchea with explosive compo- 
sitions, 160 
pastes, a34 
Schneider, B. A., critical studies 
un the chemistry of titanium, 
138 
School of Mines, Royal, xis 
Schools of chemistry, X13 
medicine, ia6 
science and art. 150 
Schnnck, B., and L. March- 
lewski, kome derivatives of 
anthraquinone, 389 
Science, Australasian Associa- 
tion for the Advancement of, 

Durham College of, 120 
present limits of, remarks on 

discourse, 197 
Roy si College of, X13 
and Art Schoola ol, Chartar« 
bouse, 150 
** Science, Wagner Pree Insti- 
tute " (review). 333 
Sciences, Imperial Academy of 

Vienna, 289 
Scientific researches, insdequscy 
of Aids and facilities for, a36 
Searle, A. B.,and A. K. Tankard, 
formation of citric acid by the 
oxidation of cane-sugar, 31, 
a35,a68 
Seed- lac, eiaminatioo of, 65 
Salenious scid, determinauon of, 

ai6 
Selenium, ele^rical properties, 
ao 
reduction of tbe adds of, 136 
Sarpenu, treatment of the bitee 
of venomous, 30 
venomous, 16a 
Seubert, K., use of glycerin as a 
beating liquid 10 Soxhlet's 
drying apparatus, 37 
and W. Pollard, atomic weight 
of molybdenum, a8i 
determination of molybdic 
acid, a93 
Shaw, G. E.. periodides of theo- 
bromine, 178 
S., aod P. P. Bedioo, argon in 
the gases of rock salt, 48 
Shefield Borough Analyst's 
Laboratory, ia6 
Pirth College, laa 
Shanatooe, W. A., "Justus von 
Uebig. his Life and Work " 
(review), 107 
Shield, J., temperature corrac- 

tioiM of barometers, 304 
Shields, I., W. Ramsay, and L. 
Mono, ocdnaion of oxygen 
and hydrogen, 3 
Schneider, B. A«, aAion of dry 

hydrochloric aoid, tad 
Silica, redudioo of, 49 
Silic«tea, opening up, 3t 
Siliade of manganese, 306 
Silicides, nickel and cobaii, aSi 
Silver, anunoniacai aalu 0^ 173 
sulphide, a^oo of intra- red 

lays on, 80 
aod gold, fraesing-poiou of, 

'34 
from iron andateel. separation 

of 100 
in copper, 76 

and manganese, separatioo, 91 
Simon, L., aAtoo of asymmetric 

kctooic compounds, 110 
Slade, M. W.. T. M. Sieveoa, 
and B. Bdmonda, *' Law of 
Oopyright in Oesigna ** (ra- 
▼ltw),«i 



Sloaaon, B. B., and L. C. Ool- 
bum. ** University of Wyo- 
ming *' (review), 60 
Smith, B. A., gold and silver in 
copper and copper matte, yii 
R. G., deuaion of sulphatea, 

&c.,39 
A., and L. Coho, ** Manual of 
Organic Cbemiatry " (ro» 
view^ aao 
C, and C P. Cross, chemical 
hiatory of the barley plant, 

B. /.,and Marv B. Pennington, 
atomic weight of tungsten, 
aai 
SmithelU, A., fUme tempera- 
tures, a63 
*'Soap and (handles. Manufac- 
ture ** (review). j68 
Society, Chemical, 43, 36, a3a, 
a64.J77.a88, 311 
PharmaceutKal, School, X15 
Physica', ao, 2x9, a4a, ab6, 304 
Boyal, 34, a8t 
Sodium niuoaoanlphate, a66 
on water, aAion of, 38 
and potaasium cyannratea, for* 
roaiion of, x6x 
Solar atmosphere and the gaa oC 
cUveite, comparison between, 
14 
atmosphere, third permanent 
radiatioa of, ta, 14 
Sonstadi, E.,produAioo of potaa- 
sium pIstiDicbloride, 333 
** Specific Poundationa of Ana- 
lytical Cbemiatry " (review), 
232 
volume aixd the genesis of the 
elements, 230, a37 
SpeAroscopic studies, chemical 
researches aod, 177, 188, 203, 
ai3. 23^ 239. 248, 239. >74. 
284, 30X, 31X 
atttdy of tbe carbooa of tba 
eledric furnace. 9 
SpeAra of argon, 66, 99 
Speeiral photomster, new, 236 
researches 00 tbe star Aluir, 
269 
Spaarum aoalyaia of minerals, 
direa, t03 
iuorescent, of argon, 78 
of helium, 87 
of Ramsay's compound of argon 

and carbon, 90 
red, of argon, 289 
Spring, W., hydrogen peroaidOk 

aSx 
Standard acid solutions, 3, 84 
Staa, j. S., chemical rcsearcbaa 
and spearosoopic studiee, 
X77, x88, 203, ax3, 226. 239, 
24d,239.<74.284,3oi,3ii 
Steam*boiler exploeiooa, 174 
Steel iogota for tool manufaanrt, 
forf^ng flat croable. 3 
microecopic examination of 

crude cement, 24 
and iron aeparatioo of gold and 
ailver from, too 
Steela, rapid determination of 
pbospboma 10,173 
tempering extra hard, 280 
Stenliaation of milk, im 
Stevens, T. M., L. Edmunds, 
aodM. W. Slade, ** Law ol 
Copyright in Ocaigoa" (re- 
view). 22 
StUbene denvativee, t88 
Straatfeild, P. W., and R. Mel- 
doia, derivativea of naphtha- 
lene, 432 
Strontittm, reviaion of tbe atomic 

weight, 18,29,41,34,72 
Stnart,!). M. l5, '^Origin aod 
Rationale of Colliery Bxplo- 
sioos" (review), 233 
Students, address, 11 x 
Sudbotongh, J. J., constitution of 
c«mpbonc acid, 187 
sttlbeoe derivstivca, t88 
Sugar, inverted, tnflaeace of lead 
acetateaoo thcdetemunatioo 
of, 186 
Snlphamlic acid, Ih i odni i vn* 
tiv«,47 



Solphate, eflorescenea of doobla 

ferrous aluminium, 289 
" Sulphate of Aluminium, Mann- 

faAure of" (review), 83 
Sulphatea. detection of, 39 
Sulphide, bydric, ftc, qualiutivo 

analysis of a aoluuon coo- 

uining, 63 
of Xiao, X to 
Sulphioide, ortbobenxoic, tt3 
Sulphur, determination, 3ii7 
vapour adUoo of, 967 
in cast metal, dUn daiafmina- 

tion, 13 
in commercial lead, detemlna- 

tion, 233 
in iron, eeumatloa, 299 
Sulphuric acid, fuming, 73 
Siilphonic acida, six dichloro* 

toluenes and their, 38 
Sulphuretted subsuoce in ooctoo 

oU,ao9 
Sulphurous apriaga, argon aad 

hslium from toe gaaea, 309 
Snperphoephates, use of, 209 
Sorgeons, Royal Collega of in 

Ireland, ta6 
Swansea, Technical lMtitnlt,xt9 
Syphoo,naw,a3 



X^KARD, A. R., aod A. B. 

^ Searle. formation of citne 
acid by the oiidation of cana 
sugsr, 31, 233, 268 
Tannin in winee, 269 

substances, behaviour of, 137 

Tardy, M.. aod Q. Boocbardat, 

aJcohufs derived from a dex- 

tro-terebeoihcne eucaly ptene, 

49 

Taruric acid, soma reaAioos, 

306 
Tanret, C, amorphoua state of 
melted bodies. 183 
molecular modifications of glu- 
cose, 234 
Tecbnicsl, chemical, aod physical 
calculations, reform, 7, ^tot, 
136 
Colleee, Bradford, tt8 
Glasgow aod Wast of Scot- 

Isod, 123 
institutes, xj6 
schools, 126 
Temperature correAioos of baro- 
meters. 304 
influsnce on ref^aAiva power, 
2b8 
Tensiometer, obssrvatioos with 

x»i99 
Tsrbiat, an element in, 292 
Terpeoes, rtsearchea 00, 3x3 
Testimonial, 23 

Theobromine, periodides of, 278 
Thermo-cbemical reaearchea oa 

lithium, 243 
Thiaie, H., -^etarminatioii of 
the Atomic Weight of (3o- 
balt" (review), 133 
Thioacatie acid, preparation oi; 

fi4 
Thio^erivativaafrom solphanilic 

acid, 47 
Thioureas, determination of the, 

Thomaa, O. L., and 8. Yooaft 
normal hexaoe, ten 
Vn aatoo of nitnc oxide, fit 
adtion of nitrogen peroxide. 

US 
compounds of fetrooa chloride, 

Thompaoo, J. M., C. L. Bloxam, 
and A. G. Bloxam, ** Che- 
mistry, Organic aod lnar> 
ganic, with Bxperiesenta" 
(review), 36 

Thomseo, J , »y«tematic arranga- 
mcnu of the chemical ele- 
ments, 89 

Thorium chromaies, 69 

Yhorpe, Am mooaxite, a mineral 
coniainiog behum, 32 
new baacnal pigment, 8« 
recent aaaleea of leocita ba* 
■altfrom VaaafiMyjl 



326 



INDBX. — SUPPLEMENT TO THE CHEMICAL NEWS. 



Jan. 10, 1896. 



TUdeo» W. A., " Hints on Teach. 

ing Elementary ChemiBtry 

in Schools and Science 

Classes" (review), 290 
Tiunium, critical stndies on the 

chemistry of, 138 
estimation, z^8 
ToUens, B., '* Rnraes Handhnch 

derKohleohydrate" (review), 

206 
Toloene, disnlphonic acids of, 58 
Tool mannfaoore, forging flat 

cmcihle steel ingots for, 5 
Toxicity of acetylene, 333 
Travers, M. W. Ramsay, and J. 

N. Collie, 47 
Trey, H.. sensltiveQess of some 

aone reaAions, 24 
Trillat, A., preparation of the 

amines of the fatty series, 

ao9 
"Trinidad Government Analyst 

Report" (review), 232 
Trinity Oollege, Dublin, Z13 
Tripheoylmetbane, snlphonated 

colouring matters derived 

from, 109 
Troost, L., and L. Onvrard, argon 

and helium in the gases from 

sulphurous springs, 309 
combination of magnesium 

with argon and helium. 153 
Tubes melted into vessels, pre- 
vention of rupture of, as 
Tungsten, atomic weight of, 221 



ULLMANN, C, prevention of 
rupture of tubes melted into 
vessels, 25 
Unger, O.. and G. Kriiss, heavy 
metallic salts of bichromic 
add. 281 
Universities and colleges, iii 
University (Allege, 114 
Colleges, Z15, 117, 119, I2Z, 

122 
of Cambridge, 113 
Dub in, 113 
Edinburgh, 122 
London, iii 
Oxford, 113 
St. Andrews, 123 
Wales. IIS 
TutorisI Collegn, 126 
•* University of Wyoming" (re- 
view) 60 
Uraninite, new gas from. 4, 271 
Uranium, determination of, 206 
Urea, transformation of ammo* 

nlum cyanate into, 46 
Uric acid, determiuation of. 40 
•* Urine, Chemistry oi " (review), 
97 



Urine, deteAton of iodine in, 24 
Utensils of aluminiam, 161 

'fTALENCE and atomic volume, 

^ relation between, 9 

Valenta, B., and J. M. Bder, red 
speArom of argon, 289 

Valeric aldehyd, 49 

Vant 't HofTs constant, experi- 
mental proof of, 273 

Vapour pressure of concentrated 
solutions of salts, 20X 
tensions of mixtures of volatile 
liquids, 167, 182, 196, 212, 231, 
238. 250, 263 

Varet, R., combining heats of 
mercury with elements, 185, 
209 
compounds of mercury cyanide, 

x6i 
double decomposftion between 
mercui V cyanide and alkaline 
and alaaline-earthy metals, 
209 
thermo-chemical researches on 
lithium, 245 

Venable, P. P.. new grouping of 
the elements. 126 

Veterinary College, Glasgow, 126 

Viaoria university, xx8, 120 

Vigoreux, M., manganese sili- 
cide, 306 
nickel and cobalt silicides, 281 

Villard, P., and R. larry, proper- 
ties of solid carbonic acid, 49 

Villiers, A., sine sulphide, zxo 

Volumetric detennination of 
metals, 166 
estimation of nickel, 92 
of phosphoric aeid, 28 

V(m Bitto, B., reagent for mono- 
valent alcohols, 257 

** Von Liebig, Justus, His Life 
and Work" (review). 207 

Von Linge, A. R., and H. Beh- 
rens, microscopic examina- 
tion of crude cement steel, 24 

Von Meyer, E., and G. Minnuni, 
** Year-book of Organic Che- 
mistry*' (review), 61 

Volt6, H. T., and if. 8. Nen- 
sudt, '* Laboratory Manual 
of Inorganic Preparations'* 
(review), 280 



TXTADDELL, J., vapour pres- 
^^ sure of concentrated solu- 
tions of salts, 201 
** Wagner Pree Institute of Sci- 
ence of Philadelphia" (re- 
view), 233 



Wales, University of, 1x5 
Wslker, J., end J. R. Appleyard, 

ethereal salts of ethsnetetra- 

carboxylic acid, 48 
and F. J. Hambly, transforma- 

tioo of ammonium cyanate 

into urea. 46 
.Wallis, L. A., and H. B. Harrop, 

** Forces of Nature** (review), 

220 
Walter, L. Edna, thio-deriva- 

tives from snlphanilic acid, 

Wanklyn. J. A., dau for the true 

atomic weight of carbon. X64 

hexylene and hexyl hydride 

from mannite, 75 
and W. J. Cooper, observations 
with a tensiometer, 199 
iwture and composition of the 
commercial Russian kero- 
sene,? 
Warren, H. N.. mannfaAore and 
commercial separation of 
glucinnm.3XO 
new form ot accumulator, 2xt 
produ€kion of cyanides, 40 
separation of gold and silver 
from iron aea steel, xoo 
Water, a^ion of sodium on, 38 
determination of in sulphate of 

ammonis, 6 
supply for London, 41, 92, Z48. 
203, 262 
*• Water, Examination of (re- 
view), 22X 
Waters, bituminous, 269 
exsmi nation of gases from 

mineral, 295 
hygienic, decision on potable 

and household. 2x0 
mineral , argon and helium in 
certain, 132 
Wechsier, M., separation of vola- 
tile fatty acids, 37 
Weight, atomic, of carbon, 364 
Weights, atomic, report of com- 
mittee on, 93, X05, X57, 167, 

Welti Mdlle L , aftive amylacetic 
acid, X09 

Werner, A., inorganic com- 
pounds. 221 

Wheat, preservation of, 6a 

Whetham, W. C. D., ** Solution 
and EleArolysis" (review), 
x6o 

Wiesbaden, chemical laboratory 



Wilcox, 



of, 149 

:, W. H, 



estimation of 



butyric acid, a So 
Wilde, H., place of^helium in the 
classification of elementary 
substances, 291, 317 



Wildermann, M., cxperimenta 
proof of van't Hoff't coo- 
atant,273 

Wiley, H. W., «< Asricnltanl 
Analysis " (reriewL 244 

Williamson, S., and T. Pordie, 
succinic adds, 253 

Wines, alum in, 309 
gqm of, x6i 
tibinin in, 269 
volatile acidity of. 209 

Winkler, 0., atomic weight of 
nickel and cobalt. 40, kz, 109 

Winogradsky, 8., retting of flax, 
393 

Winter, J., constancy of the con- 
gelation-point of some liquids 
of the organism, 281 

Wits, A., illumination by Inmin* 
escence. 104 

Wool, spontaneous combnstioo 
of. 173 

Worthington. A. M., <* The 
Splash of A Drop " (reriew), 
244 

Wnru, C. A., W. H. Greene, and 
H. F„ Keller, *' Elements of 
Modem Chemistry^ (review), 
X96 

Wynne, W. P., and J. Bmce, di- 
snlphonic adds of toloene, 58 
A. Greeves, six dichlorotolo- 
enes, 58 

"Wyoming University" (review), 
60 



\rEAST, rednaive power of, 
* 214 

Yorkshire (College, Leeds, xi8 
Young, G., synthesis of diphenyl- 

oxytriaxoline. 278 
j., and C. R. Darling, method 

of transfetring gases to 

vacuum tubes, 39 
S., and G. L. Thomas, normal 

hexanee, 277 



^ENGER, C. v., molecular 

^' physics, 3x7 

Zinc and copper alloys, 208 
chloride, a^ion of, fix 
powder, ammonia in, 57 
sulphide, xio 

Zincke's reaAion, modification 
of, 37 

Zone reactions, sensitiveness of 
some, 24 



END OF VOLUME LXXII.