OXYGEN DISCOVERED. 499 



but that it is the great bond of union, without 

 which matter could have no power of action. 



When commenting on Hunter's theory of life, 

 Mr. Abernethy observes, that the widely ex- 

 tended research into all the phenomena of nature 

 which the subject requires, is more adapted to an 

 ancient Greek philosopher, than to one of the 

 present day. He then declares himself at " a 

 loss to know what chemists now think res- 

 pecting heat whether they conceive it to be a 

 distinct species of matter, or mere motion ; and 

 that in this state of perplexity he could not ad- 

 vance one step further than Mr. Hunter had led 

 him." Alas! that great man left the theory of 

 life in almost as much obscurity as the chemists 

 have left that of heat, light, and electricity ; for 

 notwithstanding his numerous experiments on the 

 blood, he never explained the cause of its coagu- 

 lation and conversion into the various tissues. 



After the discovery of oxygen by Priestley and 

 Scheele, Girtanner, Blumenbach, Richerand, and 

 many other physiologists in different parts of 

 Europe, including Dr. Southwood Smith and 

 Dr. Holland, have maintained it to be " the life- 

 sustaining principle of the atmosphere." But it 

 is absolutely certain that oxygen exerts no in- 

 fluence whatever in maintaining the functions of 



natures of Hoffman and Cullen, the excitability of Brown, the 

 sensorial energy of Darwin, and the nisus formativus of Blumen- 

 bach, the conservative principle is a mere refuge for ignorance 

 in regard to the physical cause of all the vital functions. 



