Sept. 17, 1885 | 
NATURE 
467 
Prof. Traill, the nucleus. of a valuable local natural 
history collection has been formed. Prof. Osborne 
Reynolds’s illustrations of compression of solids was 
one of the most attractive features of the evening. 
The collection of pictures was large and highly credit- 
able, while the precious collections of old manu- 
scripts and books lent by the Earl of Crawford had 
many admirers. One of the most successful afternoon 
parties was given the same day at Tollshill Wood by Mr. 
David Stewart. Of course, of the numerous Saturday 
excursions, that to Balmoral was the most popular. In 
spite of the wretched weather 200 people must have left 
Aberdeen for Ballater at 1 p.m. and happily by the time 
the end of the railway journey was reached the weather 
greatly improved. The drive from Ballater to Balmoral 
evidently gave great enjoyment to the occupants of the 
long cavalcade of miscellaneous “machines” which 
wound along the banks of the Dee, and no less, we may 
be sure, did the sumptuous five o’clock dinner (* lunch,” 
it was called) which was provided in the ball-room of 
Balmoral. Gen. Gairdner presided at the table, and, 
atter proposing the Queen’s health, drank, by command 
of Her Majesty, prosperity to the British Association. 
Under the guidance of Dr. Profeit the guests made a 
round of the fine grounds of Balmoral, and on driving 
back to Ballater, passed Her Majesty on her return from 
a day’s outing. The excursion to Dunecht was also a 
great success, the arrangements at Lord Crawford’s 
observatory exciting much interest. 
A deputation from Birmingham is here to make ar- 
rangements for the visit to that town next year. It is 
evident that the Birmingham people mean to make the 
1886 meeting a success, though, so far as social arrange- 
ments go, it will be difficult to surpass that of Aberdeen. 
It is expected that Manchester will be the place of meet- 
ing in 1887, and for 1888 or 1889 several enterprising 
members hope to secure the selection of London, in order 
to have a meeting in common with the American Asso- 
ciation. Against this choice, however, there will probably 
be a strong protest, though of course the American Asso- 
ciation will be sure to receive an enthusiastic welcome 
whenever it chooses to visit the old country. 
Prof. Adams’s lecture on Friday attracted a large 
audience, and on Saturday evening the Music Hall was 
filled with an enthusiastic audience of genuine working 
men to listen to Mr. H. B. Dixon’s lecture and admire 
his experiments. Mr. Murray’s lecture to-night will 
certainly be of popular interest, but, summing up as it 
does the present position of aceanography, it will also be 
of the highest scientific value. The diagrams are very 
striking, and certainly original. A full report will no 
doubt appear in NATURE. 
The regret at the resignation of the secretaryship of the 
Association by Prof. Bonney is universal, though it is 
confidently expected that Mr. Atchison will be a tho- 
roughly competent successor. 
The additional arrivals up to this morning will bring 
the total number present at the meeting up to 2500. 
SECTION B 
CHEMICAL €CIENCE 
OPENING ADDRESS BY ProF, HENRY E. ARMSTRONG, PH.D., 
F.R.S., Sec. C.S., PRESIDENT OF THE SECTION } 
I Now pass to the consideration of a subject of special interest 
in this section, which I think requires the immediate earnest 
attention of chemists and physicists combined—that of Chemical 
Action. In his Presidential Address to the Association last 
year Prof. Lord Rayleigh made only a brief reference to 
chemistry, but many of us must have felt that his few remarks 
were pregnant with meaning, especially his reference to the im- 
portance of the principle of the dissipation of energy in relation 
to chemical change. A year’s reflection has led me to think 
them of peculiar weightiness and full of prophecy. I would 
* Continued from p. 453. 
especially draw attention to the closing paragraph of this portion 
of hisaddress: ‘‘ From the further study of electrolysis we may 
expect to gain improved views as to the nature of the chemical 
reactions, and of the forces concerned in bringing them about. 
Tam not qualified—I wish I were—to speak to you on recent 
progress in general chemistry. Perhaps my feelings towards a 
first love may blind me, but I cannot help thinking that the 
next great advance, of which we have already some fore- 
shadowing, will come on this side. And if I might, without 
presumption, venture a word of recommendation, it would bein 
favour of a more minute study of the simpler chemical 
phenomena,” 
Chemical action may be defined as being any action of which 
the consequence is an alteration in molecular constitution or 
composition; the action may concern molecules which are 
of only one kind—cases of mere decomposition, of isomeric 
change and of polymerisation; or it may take place between 
dissimilar molecules—cases of combination and of interchange. 
Hitherto it appears to have been commonly assumed and almost 
universally taught dy chemists that action takes place directly 
between A and B, producing AB, or between AB and CD, 
producing AC and BD, for example. This, at all events, is the 
impression which the ordinary average student gains. Our text- 
books do not, in fact, as a rule, deign to notice observations of 
such fundamental importance as those of De La Rive on the 
behaviour of nearly pure zinc with dilute sulphuric acid, or the 
later ones of Faraday (‘‘ Exp. Researches,” Series vii., 1834, 
863, e¢ seg.) on the insolubility of amalgamated zinc in this acid. 
Belief in the equation Zn + H,SO, = Hy + ZnSO, hence be- 
comes a part of the chemist’s creed, and it is generally inter- 
preted to mean that zine we// dissolve in sulphuric acid, forming 
zinc sulphate, not, as should be the case, that w/e zinc dissolves 
in sulphuric acid it produces zine sulphate, &c. In studying the 
chemistry of carbon compounds we become acquainted with a 
large number of instances in which a more or less minute quan- 
tity of a substance is capable of inducing change in the body or 
bodies with which it is associated without apparently itself being 
altered. The polymerisation of a number of cyanogen com- 
pounds and of aldehydes, the ‘‘ condensation” of ketonic com- 
pounds and the hydrolysis of carbohydrates are cases in point ; 
but so little has been done to ascertain the nature of the influence 
of the contact-substance, or catalyst, as I would term it, the 
main object in view being the study of the product of the re- 
action, that the importance of the catalyst isnot duly appreciated. 
Recent discoveries, however—more particularly Mr. H. B. 
Dixon’s invaluable investigation on conditions of chemical 
change in gases, and the experiments of Mr. Cowper with 
chlorine and various metals, and of Mr. Baker on the combustion 
of carbon and phosphorus—must have given a”rude shock, from 
which it can never recover, to the belief in the assumed sim- 
plicity of chemical change. The inference which I think may 
fairly be drawn from Mr. Baker's observations—that pure 
carbon and phosphorus are incombustible in Awe oxygen—is 
indeed startling, and his experiments must do much to favour 
that ‘‘more minute study of the simpler chemical phenomena” 
so pertinently advocated by Lord Rayleigh. 
But if it be a logical conclusion from the cases now known to 
us that chemical action is not possible between any two sub- 
stances other than elementary atoms, and that the presence of a 
third is necessary, what is the function of the third body—the 
catalyst—and what must be its character with reference to one 
or both of the two primary agents? In the discussion which 
took place at the Chemical Society after the reading of Mr. 
Baker's paper, I ventured to define chemical action as reversed 
electrolysis, stating that in any case in which chemical action 
was to take place it was essential that the system operated upon 
should contain a material of the nature of an electrolyte (Chem. 
Soc. Proc., 1885, p. 40). In short, I believe that the conditions 
which obtain in any voltaic element are those which must be 
fulfilled in every case of chemical action, There is nothing new 
in this; in fact, it practically was stated by Faraday in 1834 
(‘‘ Experimental Researches in Electricity,” series vil. §§ 858, 
8591) ; and had due heed been given to Faraday’s teachings we 
* “Those bodies which, being interposed between the metals of the voltaic 
pile, render it active, ave all of them electrolytes, and it cannot but press 
upon the attention of every one engaged in considering this subject, that in 
those bodies (so essential to the pile) decomposition and the transmission of 
a current are so intimately connected that one cannot happen without the 
other. If, then, a voltaic trough have its extremities connected by a body 
eapable of being decomposed, as water, we shall have a continuous current 
through the apparatus ; and whilst it remains in this state we may look at 
the part where the acid is acting upon the plates and that where the current 
