512 RESPIRATION. 



vegetable matter by the action of fire, and thus 

 preparing it for entering into new combinations 

 in the living body, but greatly changes its taste, 

 odour, and other sensible properties. 



The all-important function of respiration, so 

 essential to animal life, is, strictly, a chemical 

 process, by which a portion of atmospheric 

 oxygen unites with carbon to form carbonic 

 acid, with an evolution of caloric. Who then 

 can say at what precise point the operations 

 of chemistry are merged in the affinities of life, 

 as in germination, spontaneous generation, the 

 nourishment of plants, &c. ; or when the latter 

 terminate in the actions of ordinary chemistry, 

 as during the ripening of fruits ? 



There is nothing more calculated to excite our 

 admiration of the infinite wisdom by which the 

 universe is governed, than the intimate relation 

 that exists between all its physico-chemical and 

 vital operations. By the mechanical diffusion 

 of water through the atmosphere, organized 

 bodies are supplied with the greatest part of 

 their substance. The carbonic acid generated 

 by chemical action during the processes of com- 

 bustion, fermentation, and the respiration of 

 animals, affords nourishment to plants being 

 decomposed in the tissue of their leaves, where 

 crude sap is converted into cambium by the 

 evaporation of water, and the absorption of car- 

 bon ; then into starch, sugar, oils, &c. which in 



