142 



PRINCIPLES OF CHEMISTRY. 



Tht affinity 

 of chemistry 

 "plained. 



Absolute or 

 complete 

 union of prin- 

 ciples, 



does not ap- 

 pear in our 

 observations. 



xnr. 



An Explanatory Statement of the Notions or Principles upon 

 which the Systematic Arrangement is founded, which wai 

 adpotedas the Basis of an Essay on Chemical Nomenclature*, 

 By Professor J. Berzelius. 



WE may consider the affinity of chemistry as a tendency 

 by which bodies are incessantly urged. By this affinity 

 they are disposed to combine, in such proportions and in such 

 numbers of each body, that they afterwards cease to manifest 

 any farther affinity of combination, which property may from 

 that period be considered as in a state of repose or inactivity. 

 Such a combination or compound, which no longer shews any 

 affinity towards ihe greater part of other bodies, may be itself 

 called an indifferent body: If, for example sulphur, caritium, 

 andoxigen, come into contact, they tend to combine in such a 

 manner, as to produce sulphate of barytes j and in this com- 

 pound the affinities of the ingredients appears to be in a state 

 of repose ; that is to say, they constitute an indifferent com- 

 pound. 



The entire tendency or activity of the affinity is, therefore, 

 exected to arrive, by an effect, which occupies a longer or 

 shorter time, according to circumstances, at this state of 

 repose or indifference. If the elementary bodies were collect- 

 ed at the same place, and all possessed an equally strong che- 

 mical affinity, an active chemical phenomenon would ensue, 

 which would terminate in eternal repose. No force would 

 tend to change this state of repose, and such different com- 

 binations as might be thus formed, being attracted by each other, 

 by the means of gravitation and cohesion, would constitute a 

 mass or aggregate of indifferent bodies. 



But this is not the construction which takes place in nature, 

 among the surrounding bodies of that small part of the universe 

 which is submitted to our observation. A series of mutations 



* The Essay was published in the Journal de Physique, of Dr. Dela- 

 metheiie, Oct. 1811, or Tome lxxxiii. 253. It ; bounds with nevv^and 

 interesting observations ; and it is with regret that i am preventer! by it* 

 length from inserting it in our work. — The present memoir, which is 

 of considerable extent, is taken from the Memoirs of the Academy of 

 Stockholm for 1812.— W. N. 



take 



