280 CATALYSIS. 



may be occurring at the same time in the decomposition 

 of one compound by another. Such are the general 

 features of chemical science. Many peculiarities and 

 remarkable phenomena connected with chemical investi- 

 gations will be named, as the examination of the ele- 

 mentary composition of matter is proceeded with ; but, 

 although the philosophy of chemical action is of the 

 highest interest, it must not be allowed to detain us 

 with its details, which are, indeed, more in accordance , 

 with a treatise on the science than one which professes 

 to do no more than sketch out those prevailing and 

 striking features which, whilst they elucidate the great 

 truths of nature, are capable of being employed as sug- 

 gestive examples of the tendency of scientific investiga- 

 tion to enlarge the boundaries of thought, and give a 

 greater elevation to the mind, leading us from the 

 merely mechanical process of analysis up to the great 

 synthetical operations, by which all that is found upon 

 the earth for its ornament,, or our necessities, is created. 

 Among the most remarkable phenomena within the 

 range of physical chemistry are those of Catalysis, or, as 

 it has also been called, the "Action of presence"* 

 There are a certain number of bodies known to possess 



* On certain combinations of a new acid, formed of Azote, Sulphur, 

 and Oxygen; by J. Pelouze. Translated from Annales de Chiinie, vol. 

 xvi., for Scientific Memoirs, vol. i. p. 470. Some ideas of a new 

 force acting in the combinations of Organic Compounds, by Berze- 

 lius : Annales de Chimie, vol. Ixi. The conclusion come to by 

 this eminent chemist is expressed in the following translation : 

 " This new power, hitherto unknown, is common both in organic 

 and inorganic nature. 1 do not believe that it is a power which 

 is entirely independent of the electro-chemical affinities of the 

 substance. I believe, on the contrary, that it is merely a new 

 form of it; but so long as we do not see their connection and 

 mutual dependence, it will be more convenient to describe it by a 

 .separate name. I shall, therefore, call it catalytic power : 1 shall 

 also call catalysis, the decomposition of bodies by this force in 

 the same way as the decomposition of bodies by chemical affinity 

 is termed analysis. 



