q/'l/ie Centenary of the Birth of Dr. Priestley. 397 



says, he found that water might be impregnated with carbonic acid 

 gaffe : he supposes this may be useful, and therefore he gives freely to 

 the public the result of his inquiries. 



Perhaps, after all, one of the most extraordinary features in the 

 character of Dr. Priestley was the unexampled industry with which 

 he pursued the numerous subjects that came under his observation. 

 It is really surprising that a man who was engaged in deep read 

 theological and metaphysical research, who taught languages, who 

 gave instruction in civil law, who illustrated perspective and other 

 useful arts, and attended to astronomy, should be able to do all this, 

 and conduct the numerous experiments which were requisite during 

 the progress of his History of Electricity and that of the Disco- 

 veries relating to Vision, Light, and Colours, both being elaborate 

 works, requiring immense labour and diligence. Add to these the 

 subjects which have been so well noticed by those who have preceded 

 me at this meeting, all pursued with a truly philosophic spirit, and 

 with a single-minded purpose of being useful to the world ; and we 

 must consider it as a noble example of industry, and one which is 

 calculated to inspire emulation in those who engage in similar pur- 

 suits, and to excite respect and gratitude for the memory of one who 

 so ably led the way in the field of discovery and usefulness. 



Dr. Roget, Sec. R.S., on the part of the Zoological Society and 

 himself, delivered the following address; — 



As you have done me the great honour of mentioning my name in 

 connexion with the Zoological Society, of which, I must confess, I 

 am a very unworthy member, I beg leave to return, in the name of 

 that Society, our most grateful acknowledgments for the compliment 

 you have paid us. It is quite unnecessary to adduce any argument 

 to prove that the foundation of all zoological science must be laid in 

 correct views of the physiology of animals. As cultivators of that 

 science, we certainly owe a large tribute of gratitude and respect to 

 the memory of Dr. Priestley, whose discoveries have contributed so 

 largely to elucidate one of the most important of the animal functions, 

 namely, that of respiration. It must be acknowledged by every per f 

 son who has attended to the history of physiology, that, previous to 

 his time, physiologists were in a state of the most profound ignorance 

 with regard to the real nature and objects of that function: the only 

 notions entertained were those of accounting for the phenomena on 

 mechanical principles; and, if we except Mayow, no person had an 

 idea that they were of a chemical nature ; but Dr. Priestley, by the 

 discovery of oxygen, and more particularly of its disappearance during 

 its passage through the lungs, and of the evolution of another gas, 

 threw greater light on the theory of that function than it had ever 

 received before, and cleared away the obscurities which before pre- 

 vailed. And it is very remarkable that the results which he attained, 

 instead of being invalidated by subsequent experimenters, have been 

 corroborated by every person who has examined into the subject. I 

 may appeal to a gentleman whom I have the pleasure of seeing at 

 this table on the present occasion, Mr. Pepys, who has contributed 



