124 PHYSIOLOGY OF ORGANIC LIFE. 



aptitude in the latter, that the various processes 

 of secretion and nutrition are carried on. In- 

 stead, however, of supposing that the changes 

 which are produced on the blood, arise from 

 the agency of the glands, or of the part in which 

 it is deposited ; the change, for the most part, is 

 referred to the; power of the blood upon the 

 gland ; the act is stated to be a chemical, rather 

 than a living one ; and the aggregating princi- 

 ples of physiology have been abandoned to the 

 decomposing powers of chemistry. Every so- 

 lid and every fluid have in consequence been 

 analysed with the utmost accuracy, and from 

 bodies, whose elements were found to be the 

 ame, effects which are altogether different, 

 are attempted to be explained. 



If I proceed to detail the opinions which are- 

 entertained respecting the function of the or- 

 gans which subserve the office of meliorating 

 the blood from the deterioration which it con- 

 stantly sustains, they will be found most erro- 

 neous and contradictory. Instead of consider- 

 ing the lungs, (as I conceive they ought to be 

 considered,) as much organs of digestion as the 

 stomach itself, the one acting upon, and digest- 

 ing particular kinds of air, as much as the other 

 is known to do particular kinds of food ; that 

 while the latter restores the waste which the 

 blood sustains in point of quantity, the former 

 meliorates it in point of quality; and, by the 



