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Section B.— CHEMISTRY. 



Peesident oe the Section. — Professor R. Melbola, F.E.S., Foe.Sec.C.S, 



THURSDAY, SEPTEMBER 12. 

 The President delivered the following Address : — 



The State of 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 Section B on that occasion. Perhaps the best way of performino- 

 this retrograde feat will be to confront the fundamental doctrines of modern 

 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 

 conceptions have survived to the present time or not — may be taken as the 

 abstract summation of the facts, i.e., of the real and tangible knowledge existin"- 

 at the period chosen as the standard of reference. 



"Without going too far back in time I may remind you that in 1811 the 

 atomic theory of the cheraists was grafted on to the kindred science of physics 

 through the enunciation of the law associated with the name of Avoo-adro di 

 Quaregna. The rationalising of this law had been accomplished in 1845fbut the 

 kinetic theory of gases, which had been foreshadowed by D. BernouUi in 1738, and 

 in later times by Herapath, Joule, and Kronig, lay buried in the archives of the 

 Royal Society until recently 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, 

 viz., 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 signi- 

 ficance 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 1814; but no substantial chemical reasons for its adoption were 

 adduced until the year 1846, when Laurent published his work on the law of 

 even numoers of atoms rr.d the nature of the elements in the free state.* 



The so-called ' New Chemistry ' with which students of the present time are 

 familiar was, in fact, being evolved about the period when the Britisli Association 

 last assembled at Ipswich ; but it was not till some years later, and then chiefly 

 through the writings of Laurent and Gerhardt, that' the modern views became 

 accepted. It is of interest to note in passing that the nomenclature of organic 

 compounds formed the subject of a report by Dr. Daubeny at that meetino- 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 



' Ann. CMm. Plujt. [.S]. 18, 206. 



