638 SCIENTIFIC RECORD FOR 1885. 



the nature of the influence of the contact-substance, or catalyst^ as 1 

 would term it, the main object in view being the study of the product 

 of the reaction, that the importance of the catalyst is not duly appre- 

 ciated. Eecent 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 simplicity of chemical change. The inference 

 which I think may be fairly drawn from Mr. Baker's observations — 

 that pure carbon and phosphorus are incombustible in pure oxygen — is 

 indeed startling, and his experiments must do much to favor that " more 

 minute study of the simpler chemical phenomena " so pertinently ad- 

 vocated by Lord Eayleigh. (See Presidential Address to the B. A. A. 

 S., at the meeting of 1884.) 



But if it be a logical conclusion from the cases now known to us, that 

 chemical action is not possible between any two substances 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 read- 

 ing of Mr. Baker's paper, I ventured to define chemical action as re- 

 versed 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. 8oc. Proc, 1885, 

 p. 40). In short, I believe that the conditions which obtain in any vol- 

 taic element are those which must be fulfilled in every case of chemical 

 action. There is nothing new in this; in fact it was stated by Faraday 

 in 1848 {Exp. Researches, series vii, § 858 and § 859) ; and had due heed 

 been given to Faraday's teaching, we should scarcely now be so ignorant 

 of the conditions of chemical change. {Chem. News, lit, 135.) 



Suggestions as to the Cause of the Periodic Law and the Nature of the 

 Chemical Elements. (By Prof. Thomas Carnelley.) — The truth of the pe- 

 riodic law of the chemical elements is now generally allowed by most 

 chemists. ^Nevertheless, but little has been done towards attaining a 

 reasonable explanation of the law. This prompts the author to offer a 

 few suggestions on this subject. Even long before the discovery of the 

 periodic law many chemists had pointed out certain numerical relation- 

 ships existing between the atomic weights of bodies belonging to a given 

 group, and had, hence, supposed that the elements belonging to the sev- 

 eral natural groups were not primary, but were made up of two or more 

 . simpler elements. These conclusions, however, were more or less frag- 

 mentary and referred only to particular groups of elements. In the 

 light of the periodic law the author has made a general extension of the 

 fragmentary conclusions of Dumas, and has brought that law into jux- 



