(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "The Chemical News and Journal of Industrial Science; with which is ..."

This is a digital copy of a book that was preserved for generations on library shelves before it was carefully scanned by Google as part of a project 
to make the world's books discoverable online. 

It has survived long enough for the copyright to expire and the book to enter the public domain. A public domain book is one that was never subject 
to copyright or whose legal copyright term has expired. Whether a book is in the public domain may vary country to country. Public domain books 
are our gateways to the past, representing a wealth of history, culture and knowledge that's often difficult to discover. 

Marks, notations and other marginalia present in the original volume will appear in this file - a reminder of this book's long journey from the 
publisher to a library and finally to you. 

Usage guidelines 

Google is proud to partner with libraries to digitize public domain materials and make them widely accessible. Public domain books belong to the 
public and we are merely their custodians. Nevertheless, this work is expensive, so in order to keep providing this resource, we have taken steps to 
prevent abuse by commercial parties, including placing technical restrictions on automated querying. 

We also ask that you: 

+ Make non-commercial use of the files We designed Google Book Search for use by individuals, and we request that you use these files for 
personal, non-commercial purposes. 

+ Refrain from automated querying Do not send automated queries of any sort to Google's system: If you are conducting research on machine 
translation, optical character recognition or other areas where access to a large amount of text is helpful, please contact us. We encourage the 
use of public domain materials for these purposes and may be able to help. 

+ Maintain attribution The Google "watermark" you see on each file is essential for informing people about this project and helping them find 
additional materials through Google Book Search. Please do not remove it. 

+ Keep it legal Whatever your use, remember that you are responsible for ensuring that what you are doing is legal. Do not assume that just 
because we believe a book is in the public domain for users in the United States, that the work is also in the public domain for users in other 
countries. Whether a book is still in copyright varies from country to country, and we can't offer guidance on whether any specific use of 
any specific book is allowed. Please do not assume that a book's appearance in Google Book Search means it can be used in any manner 
anywhere in the world. Copyright infringement liability can be quite severe. 

About Google Book Search 

Google's mission is to organize the world's information and to make it universally accessible and useful. Google Book Search helps readers 
discover the world's books while helping authors and publishers reach new audiences. You can search through the full text of this book on the web 



at |http : //books . google . com/ 



?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. 

*** Our Notes and Queries column was opened for the purpose of 
giving and obtaining information likely to be of use to our readers 
generally. We cannot undertake to let this column be the means 
of transmitting merely private information, or such trade notices 
as should legitimately come in the advertisement columns. 
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. 

— BOI?».A.OIO-Cry»t. and powder. 

OITI^IO— Cryst. made in earthenware. 

Q-A-XjXjIO— Pfom best Chinese galls, pure. 

S-A-XjIOITXiIO— By Kolbe's process. 

T-A-^TINriO— I'or Pharmacy and the Arts. 

LIQUID CHLORINE 

(Compressed in steel cylinders). 

FORMALIN (40^ CHaO)— Antiseptic and Preservative. 

POTASS. PERMANGANATE— Cryst., large and small, 

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&7, CROSS LANE, LONDON, E.G. 



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- 
try, will be forwarded 00 application. 
The SESSION COMMENCES OCTOBER xst. 

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



Wanted, General Manager to a Limited 
Company, principally engaged in the manufaAure of Alkali 
sad Bleach. Mutt be thoroughly acquainted with the Chemical 
Procetses at present in nse, and also with proposed ElcArolytical 
Processes. In addition to having a thorough knowledge of Praaicsl 
Chemittry and Ble^ricity, he must be capable of takmg charge of 
the BreAion of Plant, and assome the general management- of the 
bnsiness. Permanent position and good remuneration. Any com- 
mnnication regarded as striaiy coofidential.~Addresa, giving full 
^rticttlars and salary required, to ** Alkali," care of Crotuey, Moir, 
4 Co., S7At Coleman Street, Loadooi B.C* 



CHEAP SETS OF STANDARD BOOKS. 

In good condition, and ttnt Caff%ag§ Prt$ in Groat BriUdm, 
Watte' Diay. of CbemUtry and the AUied Sciences ; eom^UUsit, 

UMAsaiDOBD BOiTiON , 9 vois. cloth, i866-8i, £iK, for £7 7s. 
Do , Niw Ed.t 3 volt.. N«w. 1888-92 {Special o/fer), £6 14a- for £4 158. 
Thorpe's Didty. of Applied Chemietry (compUti). The com- 
panion work to •• Watts." 3 vols., New, £7 79. for £s las. 
Joaroal of the Chemical Society, 1663 to 169a, 43 vols., d., £19 io«. 

Ditto, 1878 to x8qx, compute, a8 volt. £S 8t. 
Chemical News, Couplbtb Sbt, 1860—89, 60 volt, cloth, £18 los. 
ProceediojgB of the Royal Society of London, Complbtb SBt 

from X854 to X889 ; 39 volt., 8vo. cloth. Scares, £10 xos. 
Nature : complete set i860 to x888; 39 vols, cloth, £8 8t. 
Dinglera Poisrtechnieches Journal. 183Z— 1890. 231 vols., of. £30. 
Chemistry spplied to Arts and ManufaAures by writers of eminence 

{Schorlimmer and otkere) ; engravimgs, 8 vols. (1880), £4, tor 3)8/6. 
Qmelin'e Handbook of Chemistry (Organic and Inorganic), by 

Hy. Watts, complete set, 19 vols, d, scarce, £20, for £8 8s. 
Trans. Royal Soc. of Edin., 1788 to 1890, 36 vols., 4to, h.calf, £45. 
Iron and steel Instit. Journal, 1876—89, 29 vols., d., £xo los. 

WM. F. CLAY, Bookseller, Teviot Piece, EOINBUROH. 

CITY AND GUILDS OF LONDON INSTITUTE. 

PBBtiDBNT-H.R.H. the PRINCE OP WALES, K.G. 
SESSION Z895-96. 

The Courses of Instrudlion in ENGINEER- 
ING sod CHEMISTRY at the Institute's Colleges commence 
in October, and cover a period of two to three years. The Matbicu* 
LATIOM ExAMiNATiOM Of the Central Technical College will be held 
on September Z7th to aoth, and the Entbancb Exauination of the 
Day Department of the Technical College, Finsbury,on September 
17th. 

CITY AND GUILDS CENTRAL TECHNICAL 
COLLEGE 
(Exhibition Road, S.W.), a College for higher Technical Instmaioo 
for Students not under 16 years of age preparing to become Civil, 
Mechanical, or Electrical Engineers, Ghemicsl and other Manufac- 
turers, and Teachers. 

Thb Matriculation Examination will be held on September 17th 
to aoth, and the new Session will commence oa OAober xst. 

PfofessofS'.^O. Henrici, LL.D., P.R.S. ( Mathematics )» W. C 
Unwin,.F.R.8.,M.l.C.E. (Civil and Mechanical Engineering), W. E. 
Ayrton, P.R.S. (Physics and Elearical Engineering), H. £. Arm- 
strong, Ph.D., F.R.S. (Chemistry). 

CITY AND GUILDS TECHNICAL COLLEGE, Flnebury 
(Leonard Street, City Road, E.G.). The DAY DEPARTMENT 
provides Courses of Intermediate Instruction for Students not under 
14 ycers of age, preparing to enter Mechanical or EleArical Engin- 
eering and Cneroical Industries. 

Thb Entrancb Examination will be held on September xyth, and 
the new Session will commence on OAober xst. 

Professors:— S. P. Thompson. D.Sc, F.R.S. (Elsflrical Engineer* 
ing), J. Perry, D.Sc, P.R.S. (MechaoiCAl Engineering). R. Meldola* 
F.K.S. (Chemistry). 

JOHN WATNEY, 

City and Guilds of London Institute, Hon. Secretary. 
Gresham College, BasinghaU Street. E.C. 



AC£XON£ — Answering all requirements. 

.A.GXID .A-OIHj1?IO— P««»t and sweet. 

- BOI^-AuOIO— Cryet. and powder. 

CI'X'JWIO— Cryst. made in earthenware. 

Q--A-IjIjIO— Frow t>««t Chinese galls, pure. 

S-A-IilO YlilO-By Kolbe's proceaa. 

T-A-GCnSriO— Por Pharmacy and the Arta. 

LIQUID CHLORINE 

(Compressed in steel cylinders). 

FORMALIN (40^ CH20)--Antiteptic and Preservative. 

POTASS. PSRMANGANATE—Cryst., large and smaU, 

SULPHOCYANIDB OP AMMONIUM. 

BARIUM. 

POTASSIUM. 

TARTAR EMETIG-Cryst. and Powder. 

TRIPOLI AND METAL POWDERS. 

ALL CHEMICALS FOR ANALYSIS AND THE ARTS. 



Wholesale Aients— 

A. & M. ZIMMERMANN, 

6 A 7, GROSS LANE LONDON, E.O. 



< 



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. 



NOTES AND QUERIES. 

*^* Our Notes and Queries column wai opened for the purpose of 
giving and obtaining information likely to be of use to our readers 
generally. We cannot undertake to let this column be the means 
of transmitting merely private infotmation, or such trade noticea 
as should legitimately come in the advertisement columns. 

Wanted, a Retpiratoc— Can any reader supply the name of 
maker of a respirator suitable for wear in the laboratory ? ProteAion 
is desired against entrance of hydric snlpbide into tbe luogi either 
by motttli or aosc^AsrHYXU, 



ELEMENTARYQUALITATIVE ANA- 
LYSIS :suiub]e for Orgsnised Science Schools. By PRANK 
CLOWES, D.Sc. Lond., Professor of Chemistry in University 
CoUegt, Nottingham, and }. BERNARD COLBMAK. Senior 
Demonstrator; of Chemistry in University Collega, Nottiof ham* 
With Engravings. Post 8vo, ax. 6d, 

BY THE SAME AUTHORS. 

QUANTITATIVE ANALYSIS: specially 

adapted for Collegea and Schools. Third Edition, with 100 En- 
gravings, Post 8vo. r Jitti feoify. 

VALENTIN'S QUALITATIVE ANA- 

LYSIS. Edited by Dr. W. R. HODGKINSON, F.R.S.E., Pro- 
fessor of Chemistry and Physios in the Royal Military Academy 
and Artillery College, Woolwich. Eighth Edition, Revised and 
Enlarged, 8s. 6d. 

BLOXAM'S CHEMISTRY, INOR- 

GANIC AND ORGANIC, with ExperimenU. Re-written and 
Revi&ed bv JOHN MILLAR THOMSON. Piofassorof Chamia- 
try. King's College, London, and ARTHUR G. BLOXAM, 
Head of the Chemistry Departmebt. The Goldsmiths' Institute, 
New Cross, London. Eighth Edition, with a8i Engravings, 8vo, 

BLOXAM'S LABORATORY TEACH- 

ING; Or, Progressive Exercises in PraAical Chemistry. 
Edited by ARTHUR G. BLOXAM, Head of the Cbamiat^ 
Department. The Go'dsmiths' Institute, London. Sixth Edition. 
Revised and much Enlarged, with 80 Woodcots, Crown 8vo, 
6s. 6d. 

CHEMISTRY OF URINE ; a Pra<5lical 

Guide to the Analytical Examinations of Diabetic. Albuminoas. 
and Gouty Urine. By ALFRED H. ALLEN, F.I.C, F.C.S. 
With Engravings, 8vo, yi. 6d. 

London : 
J. & A. CHURCHILL, ix, Nbw Burlington Strbbt, 



yUST PUBLISHED, Largi Crown Svo.,with Diagrams 
and Working Drawings, 71. 6d, cloth, 

THE CYANIDE PROCESS 

FOR THE 

EXTRACTION OF GOLD, 

And its Practical Application on the Witwaterarand 
Gold Pielda in South Africa. 

By M. EISSLER, Minino Enoinbbr, 
Author of *' The MeUllurgy of Gold," &c. 

** This book is just what was needed to acquaint mining men with 
the aftual working of a proceaa which is not only the most popalar, 
but it, as a general rule, tbe most successful for the eztraAios of gold 
from tailings."— Affffing Journal. 

Londok: 
CROSBY LOCK WOOD & SON, 7, Stationera* Hall Court. B.C. 

UNIVERSITY COLLEGE, BRISTOL, 
CHEMICAL DEPARTMENT. 
Professor— SYDNEY YOUNG, D.Sc, P.R.S. 
LeAurer-ARTHUR RICHARDSON, Ph.D. 
The SESSION 1895-96 begins on OCTOBER 3rd. LeAures on 
Inorganic, Organic, and Advanced Chemistry will be delivered during 
the Session. The Laboratories are fitted with the most recent im- \ 
provements for the study of PraAical Chemistry in all its branches. | 
In the Evening, Ledtures on Inorganic Cbemiatry, at reduced feea, 
are delivered. Several Scholarships are tenable at tbe College. 
CALENDAR, containing full information, price xs. (by poat 

IS. s<i)> 

For ProspeAas and farther particulars apply to— 

JAMES RAFTER, Secretary. 



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. 



The Worlds Wonders Series. 

A New Serits of Popular Books treatins of the present- 
day Wonden of Science and Art. Well written, printed on 
good paper, and fuUy illustrated. 

Crown 8vo, 160 pages. Handsome Cloth Cover. 

Price ^s. ^d. each. 

** Books that should stimulate slumbering genius in those 
who read thtrn,"'- Morning Leader, 

Chemists and their Wonders. The 

Story of the Applicatioa of Chemistry to varioas Arts and Manu- 
fsaares. By P. M. Holmes. 

ASTRONOMBRS AND THEIR OBSERVA- 
TIONS. Bv Lucv TAYLoa. Revised snd Preface written by 
W. Thvnnb Limm, B.A.,P.R.A.S., formerly of the Royal Obier- 
vatory» Greenwich. 

Enqineers and their Triumphs. By 

F. M. HoLMSS, Autlior of " Four Heroes of India," dec. 

Musicians and their Compositions. 

By J. R. OSIFFITHS. 

Electricians and their Marvels. 

By Walter Jbkkolo, Author of " Michael Faraday : Man of 
Science,** Ac, 
A copy of either 0/ the above mil be sent Post Free by the Publishers 
on receipt of a Pottat Order for is, 64., or may be ordered through any 
bookseller, 

London : S. W. PARTRIDGE & CO., 
8 As 9» Fatomoster Bow. 



J. & A. CHURCHILL, 
PU BLISHER S, 

PRACTICAL CHEMISTRY AND 

QUALITATIVB ANALYSIS ; SoeciaUy adapted for CoUecet 
" ' • By FRANK CLOWES, D.Sc. Profeaaor of Che- 



and Scheoli. , 

raistry in Uoiveriity Coilege, Nottingham. 
84 Engravings, Poit 8vo, 8«. 6d. 



Siith Edition, with 



ELEMENTARYQUALITATIVE ANA- 

LYSIS ; tuitable for Organised Science Schooii. By FRANK 
CLOWES, D.Sc. Lond., ProfeMor of Chemistry in University 
College, Nottingham, and J. BERNARD COLEMAN, Senior 
Demonstrator- of Chemistry in University College, Nottingham. 
With Engravings. Pokt Svo, 2S, 6d, 

BY THE SAME AUTHORS. 

QUANTITATIVE ANALYSIS: specially 

adapted for Colleges and Schools. Third Edition, with xoo En- 
gravings, Post 8vo, 9s. i3*^ 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 Military Acaudemy 
and Artillery College, Woolirich. Eighth Edition, Revised and 
Enlarged, Ss, 6d, 

BLOXAM'S CHEMISTRY, INOR- 

GANIC AND ORGANIC, with ExperimenU. Re-written and 
Revised by JOHN MILLAR THOMSON, Piofessorof Chemis- 
try. King's College, London, and ARTHUR O. BLOXAM» 
Head of the Chemistry Department, The Goldsmiths' Institute, 
New Cross, London. Eighth Edition, with 281 Engravings, 8vo, 
i8f. 6<f. 

BLOXAM'S LABORATORY TEACH- 

INO; Or, Progressive Exercises in PraAical Chemistry. 
Edited by ARTHUR G. BLOXAM, Head of the Chemistry 
Department. The Go dsmiths' Institute, London. Sixth Edition. 
Revised and much Enlarged, with 80 Woodcuts, Crown 8vo, 

CHEMISTRY OF URINE; a Pradlical 

Guide to the Analytical Examinations of Diabetic, Albuminous, 
and Gouty Unne. By ALFRED H. ALLEN, F.I.C., F.C.S. 
With Engravings, 8vo, ?s. 64. 



London : 
J. & A. CHURCHILL, 11, New Burlington Street. 

A.CEXONE — Answering all requiremenu. 

JL.C/XJO J^OIEjTIO— P««*»t and tweet. 

- IBOIR-A-OIO— Cryst. and powder. 

OITIRIO— Cryat. made in earthenware. 

- Gh-A-IjXjIO— Fron» best Chinese galls, pure, 

S-A-XjIOYXiIO-By Kolbe'a procesa. 

T-A-I?r JbTIC— Po*" Pharmacy and the Atts. 

LIQUID CHLORINE 

(Compressed in steel cylinders). 

FORMALIN (40^ CH2O)— Antiseptic and Preservative. 

POTASS. PBRMANOANATB-Cryat., large and amaU, 

SULPHOCYANIDB 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, CROSS LANE LONDON, E.G. 



Albumens, Pastes, Gums, Glues, Prepared 

^^ Horn- Pitha, Vegetable Sixes, Ac, ftc.^W. KINO, Benaon 
Street, Liverpool.j 



CBiiue«LNiws,l 
Aoj. 9, iSjJ. I 



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. 




MESSRS. MACMILLAN & CO/S BOOKS 

FOR 

CHEMICAL STUDENTS, 

ANALYTICAL CHEMISTRY. By N. Menschuthn, 

Professor in the University of St. Petersburg. Translated from 
the Third German Edi ion, under the aupervision of the Author, 
by jAues Locks. Medium Bvo., 17s. net. 

CHEMICAL ANALYSIS OF OILS, FATS, WAXES, 

and of the. Commercial ProduAs derived therefrom. From the 
German of Prof. Dr. R. BsKaoiKt. Revised and Enlareed by 
Dr. J. Lbwkowitscu, F.I.C. P.C.S , formerly Technical Mana> 
ger at the WhitehsU Soap Works, Leeds ; Consultiog Chemist 
and Chemical Engineer. 8vo, 215. net. 

THEORETICAL CHEMISTRY FROM THE STAND- 
POINT OF AVOGADRO*S RULE AND THERMO- 
DYNAMICS. B^ Professor Walter Nbrmst, Ph.D., of the 
University of Gdttingen. Translated by Prof. Charles Skselb 
Palmer, Ph.D., of the University of Colorado. With 26 Wood- 
cuts and Two Appendices. 8vo, 155. net. 

A TREATISE ON CHEMISTRY. By Sir h. E. 

Roscoi, F.R.S., and the late C. Schorlbmkbr, PR.S. 
Vol. I. The Non-Metallic Elements. New Edition. Completely 
Revised by Sir H. E. Roscoe, assisted by Drs. H. G. ddmaa 
and A. Harden. With 374 Illustrations and t Portrait of Daltoa 
engraved by C. H. Teens. 8vo., 2ts. 

Vol. II. Part I. Meuls. i8f. Vol. II. Part II. Metala. 
iBs. Vol. III. Organic Chemistry. Parts I., II.. IV., and 
VL, 21S. each. Parts III. and V. i8j. each. 

THE RISE AND DEVELOPMENT OF ORGANIC 

CHEMISTRY. By Cakl Sohorlemmbr, LL.D., F.R.s:, Uw 
Professor of Organic Chemistry in the Owens College, Manchea- 
ter, Viaoria University. Revised edition. Edited by Arthur 
Smithrlls, B.Sc Crown 8vo., 5s. net. 

ESSAYS IN HISTORICAL CHEMISTRY, ByT.E. 

Thorpe, F.R.S., Professor of Chemistry in the Royal College of 
Science, South Kensington, London. Crown 8vo., 8s. 6d. net. 

HISTORY OF CHEMISTRY FROM THE EARLIEST 

TIMES TO THE PRESENT DAY. By Ernest von Mbtbr 
Ph.D. Translated by Gborgb McGowan, Ph.D. 8vo. 14J. set 

EXPERIMENTAL PROOFS OF CHEMICAL THEORY 

FOR BEGINNERS. By William Ramsay, Ph.D., F.R.S., 
Professor of Chemistry ia University College, London. Second 
Edition. Pot 8vo., 2S. 6d. 

OUTLINES OF GENERAL CHEMISTRY. By Prof. 

WiLHBLM OsTWALO. Translated by J. Walksr, D.Sc. Ph.D. 

8vo., los. net. 

INORGANIC CHEMISTRY FOR BEGINNERS. By 

Sir Henry Roscob, F.K.S. Assisted by Joseph Lunt, B.Sc. 
Globe 8vo , 2s. 6d. 

LESSONS IN ELEMENTARY CHEMISTRY, INOR- 

GAMC AND ORGANIC. By Sir H. E. Roscob, P.R.S. 
Sixth Edition, thoroughly Revised. 4s. 6i. 

A TEXT-BOOK OF INORGANIC CHEMISTRY. By 

Prof. Ira Rbmsen. 8vo. its. 

INORGANIC CHEMISTRY. Bythciamc. Crown 8vo., 
6s. M. 

ORGANIC CHEMISTRY. By the same. Crown 8vo.. 

65.64. 

THE ELEMENTS OF CHEMISTRY. By the same. 

New Edition. Fcsp. 8vo. . 21. 6d. 

PRACTICAL INORGANIC CHEMISTRY. By Francis 

Jones, F.R.S.E. 2s. 6d, 

PRACTICAL ORGANIC CHEMISTRY. By J.B. Cohen, 

Ph.D. 2S.6d, 

LESSONS IN ORGANIC CHEMISTRY. Part I, 

Elementary. By G. S. Turpin. M.A., D.Sc, Principal of the 
Technical School, Huddertfield. Globe 8vo., 2s. 6d. 

A SERIES OF CHEMICAL PROBLEMS, WITH KEY. 

By T. E. Thoxpi, F.R.S. Nnr Edition. Keviied by W. Tat*. 

THE ELEMENTS OF THERMAL CHEMISTRY^ By 

M. M. Fattisom Muir, M.A., F.R.S.E., EMiited by D. if. 
Wilson. With a Plate. 8vo., 12s. 6d. 

A TEXT-BOOK OF THE PHYSIOLOGICAL CHEMIS- 

TRY OF THE ANIMAL BODY, including an Account of tSe 
Chemical Changes occurring in Disease. By Arthus Gamgxb, 
M.D., F.R.S. Vol. II. The Physiological Chemistry of Dice»^ 
tion. With two Chromo-Lithographic Charts by Spxllom muI 
Wilkinson. 8vo.,i8i. (Vol. f., 8vo., x8s.). « ■»« 

MACMILLAN & CO., LONDON. 



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 





.^ 

^ 


N 














J 


"S 




«H 


■*^B»— 




d 

a 


-21 




> 


\ 












»•■■ 








'"r^ 


"fla^ 


^ 


V 




u 




\ 










s^ 

s 




o 










%. 


tt 


9- 
00 


\\ 






\ 






X 


ft 




9\ 










"8 






\\ 






c^ 


N 




o 
III 


r 

s 




1. 










2 J2 

1 


r* 


r8* 


\ 


1 






< 


\ 


< 
o 






r^ 












■*^ 


^ 


^ 


\ 










\ 


§ 




li. 






1 








n 

PS 

o 


V 


5fe^ 


•^■a. 








^ 


s. 




III 










S£ 


^ 40 


(M 

09 _ 




u 




^***V 


^SlQ^ 


^ 


sa^ 




\ 












^ 


p 


bit:} 




rl 










:f 


9 


^^ 


I;- 




r^^ 








2 




C\l~ 




i*^ 










y 


2 




J 

/- 


N 


\^ 




^- 


"w 












b. 

O 


in 

o 

s 




- 


ir<^ 




"C 




< 

i 


iL 


- A.2 

I"" 

— OlS 
Q 






rti 












^ 


r 


^v^"^ 




^^ 


V 


u 


s ^ 






_ ,-,^ 


^ 


r< 


in 
o 


1 

C3 


o> 





— 




^r' 




5 '^ 
n 






\x 


ir<^ 


<< 




(A 
C 

o 


in 

« 

5 




c 

-I 


> 






at '^ 

i 


--" 


"^ 








-1 
< 


s 




J- 








u 
fa 




fs 








\ 




« 
10 




i 












c 

\ 

< 


> 


• 






V 

1 


\\ 












>c 
i«.c 

lA 

^ 










S 




r 


0) 

in 

*^ 








^^N 


^ 


o. 

V) 

o 
s 
1- 





1 










i 


KM 

1.^ 


giC 








\ 


^ 


< 

^ 

R 


; 


f 


1 


a 
u 
1- 






, 1 


.^— 


•I 

1 








\ 




/ 




6 

CM 


c 


i 


i 

1 
f 


*5 1 


I 


ay 


^-1 

in ^ 




1 




V \ 


w 


/ 


J 

2 

o 


o 
— 6— 




8 




CD 


in 

IM 

1 




in 

1 




^^ 


x^ 


^ 


—6— 


I 


b 




; 


f -1 


■ ^ 


1 


^ 

4 


• 1 


- 1 


t 1 

H 




h + 




5^ 


^ 

H 


: ? 


f, i 


1 


1 


1 



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. 

^OIE ^GIBI'IO— Pwfest and sweet. 

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 an