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NATURE 
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THE BRITISH ASSOCIATION MEETING AT 
EDINBURGA 
SECTION A. 
On Temperative Equilibrium of an Enclosure in which there is 
a Body in Visible Motion, by Prof. Balfour Stewart, F.R.S.— 
It is now several years since Prof. Tait and the author of this 
paper came jointly to entertain the belief that there is some 
transmutation of energy, the exact nature of which is unknown, 
when large bodies approach and recede from one another. It is 
desirable to vindicate an idea of this nature, both from the theo- 
retical and the practical point of view—that is to say, we ought, 
if possible, to exhibit it as a possible deduction from those laws 
of nature with which we are already acquainted ; and, on the 
other hand, it ought to be supported by observations and experi 
ments of anewkind. In our case the experiments and observa- 
tions have been of a difficult nature, and are yet in progress, it is 
therefore premature to bring them before the notice of this sec- 
tion. A theoretical vindication of the idea has been obtained by 
Prof. Tait, and more recently one has occurred to the author of 
these remarks, which he now ventures to bring before the section. 
Men of science are now sufficiently well acquainted with Preyost’s 
theory of exchanges and its recent extension. We know that in 
an enclosure, the walls of which are kept at a constant tempera- 
ture, every substance will ultimately attain the very same tem- 
perature as these walls, and we also know that this temperature- 
equilibrium can only be brought about by the absorption of 
every particle being exactly equal to its radiation, an equality 
which must separately hold for every individual kind of heat 
which the enclosure radiates. This theoretical conclusion is sup- 
ported by numerous experiments, and one of its most important 
applications has been the analysis of the heavenly bodies by 
means of the spectroscope. Let us now suppose that in such 
an enclosure we have a body in visible motion, its temperature, 
however, being precisely the same as that of the walls of the 
enclosure. Had the body been at rest, we know from the theory 
of exchanges that there would have been a perfect equilibrium 
of temperature between the enclosure and the body ; but there 
is reason to believe that this state of temperature-equilibrium is 
broken by the motion of the body. For we know both from 
theory and experiment that if a body, such for instance as a star, 
be either rapidly approaching the eye of an observer or receding 
from it, the rays of the body which strike the eye will no longer 
be precisely the same as would have struck it had the body been 
at the same temperature-and at rest ; just as the whistle of a rail- 
way engine rapidly approaching an observer will have to him a 
different note from that which it would have had if the engine 
had been at rest, The body in motion in the enclosure is not 
therefore giving the enclosure those precise rays which it would 
have given it had it been at the same temperature and at rest ; 
on the other hand, the rays which are leaving the enclosure 
are unaltered. The enclosure is therefore receiving one set of 
rays and giving out another, the consequence of which will be a 
want of temperature-equilibrium in the enclosure—in other words, 
all the various particles of the enclosure will not be of the same 
temperature. Now, what is the consequence of this? The con- 
sequence will be that we can use these particles of different | 
temperature so as to transmute part of their heat into the enerzy 
of visible motion, just as we do in a steam engine ; and if it is 
allowable to suppose that during this process the moving body 
has retained all its energy of motion, the result will be an in- 
crease of the amount of visible energy within the enclosure, all the 
particles of which were originally of the same temperature, But 
Sir W. Thomson has shown us that this is impossible ; in other 
words, we cannot imagine an increase of the visible energy of 
such an enclosure unless we acknowledge the possibility of a 
perpetual motion. It is not, therefore, allowable to suppose that 
in such an enclosure the moving body continues to retain all its 
energy of motion, and consequently such a body will have its 
energy of motion gradually stopped. Evidently in this argu- 
ment the use of the enclosure has been to enable us to deduce 
one proof from the known laws of heat and energy, and we may 
alter the shape of the body without affecting the result ; in other 
words, we should expect some loss of visible energy in the case 
of cosmical bodies approaching or receding from one another. 
Observations on Water in Frost rising against Gravity, rather 
than Freezing in the Pores of Moist Earth, by Prof. James 
Thomson, LL.D., of Belfast. In this paper Prof. Thomson, in 
continuation of a subject which he had brought before the 
British Association at the Cambridge Meeting in 1862 on the | 

Disintegration of Stones exposed to Atmospheric Influences, 
adduced some remarkable instances which he had since carefully 
observed, In one of these observed by him in February 1864, 
he showed that water from a pond ina garden had in time of 
frost raised itself to heights of from four to six inches above the 
water surface level of the pond by permeating the earth bank, 
formed of decomposed granite, which it kept thoroughly wet, 
and out of the upper surface of which it was made to ascend by 
the frost, so as to freeze as continuous columns of transparent ice 
rather than that it would freeze in the earth pores. From day 
to day during the frost the earth remained unfrozen, while a thick 
slab of columnar ice formed itself by new water coming up from 
the pond, and insinuating itself forcibly under the bases of the 
ice columns so as to freeze there, pushing them up, not by hy- 
draulic pressure, but on principles which, while seeming to have 
been previously not noticed, appear to involve considerations of 
scientific interest, and to afford scope for further experimental 
and theoretical researches. 
SECTION B. 
A REPORT On the Publication of Abstracts of Chemical 
Papers was read by the secretary (Dr. Thorpe) The com- 
mittee, which consisted of Profs. Williamson, Roscoe, and 
Frankland, having charge of the matter, said they were glad 
to be able to announce that regular monthly reports of the pro- 
gress of chemistry have been published since April last by the 
Chemical Society. These reports have been rendered as far as 
possible complete, by giving abstracts, more or less full, of all 
papers of scientific interest, and of the more important papers 
relating to applied chemistry. The abstracts have been made 
by chemists, most of whom are members of the Society, whose 
zeal for science has induced them to undertake the work for the 
small honorarium which the Council has been able to offer. A 
numerous Committee of Publication has been formed, whose 
members gratuitously undertake the revision of proofs, and a 
comparison of abstracts with the original papers. The com- 
mittee feel that their thanks are due to those gentlemen engaged 
in the work for having already so far succeeded in accomplishing 
a task of such difficulty and importance, and they confidently 
hope that their continued exertions will still further perfect the 
details of the scheme, so as gradually to increase the usefulness 
of the report. It is right to state that the funds of the Chemical 
Society, available for the purpose of the report, although so 
opportunely aided by a grant of roo/. from the British Associa- 
tion, were insufficient to defray the necessary expenses, and that 
voluntary contributions to the amount of upwards of 200/. have 
been received towards the cost of publication for the first year 
up to April 1872. There is good reason to believe that the 
expectations entertained of the usefulness of these reports will be 
fully realised by their continuance on the present system ; 
and that they will be found largely to conduce to the progress of 
the science wherever the English language is spoken. 
Prof. Williamson said it had long been felt in England that 
some equivalent was needed for those admirable annual reports 
which have long been published in Germany, and of which the 
value was so.very great to workers in chemistry. To meet that 
want was the object the committee had in view. 
A vote of thanks was given Prof. Williamson for his exertions 
in connection with the matter. 
Dr. Thorpe reada paper On Phosphorus Chlorides. He said he 
had attempted to prepare the missing oxichlorides analogous to 
those obtained from vanadium by Roscoe, but without success. 
When the phosphoryl trichloride is heated with zinc in a sealed 
tube, the oxygen is withdrawn and phosphoric chloride is obtained. 
He had also prepared sulpho-chloride of phosphorus by the action 
of sulphide of phosphorus on the penta-chloride of phosphorus. 
Mr. Pattison Muir made a communication Oz ax Antimony 
Ore from the Thames, New Zealand. The specimen analysed 
was beautifully crystallised and almost chemically pure antimony 
sulphide, containing only traces of arsenic and antimony. Mr. 
John Dalzell communicated a paper On Suphur Dichloride. He 
has repeated Hiibner’s experiments, and finds that the compound 
actually exists at low temperatures. Dr. Wright gave a révmé 
of his researches Ov the Derivatives from Codeia. An account 
of these investigations has already appeared in our columns, 
Mr. Tichborne read a paper Ox the Dissociation of Molecules by 
feat, and showed some very pretty lecture experiments on the 
subject. Mr. J. G. Buchanan read a paper illustrated by diagrams 
On the rate of Action of Caustic Soda on a Watery Solution of 
