646 RESULTS OF MULLER, BERGMAN, 



giving the analyses of Michaelis, Macaire, and 

 Marcet, they have generally omitted to state 

 from what animals the blood was obtained. 



Now if it be true, that carnivorous animals 

 consume from 20 to 50 per cent, more oxygen by 

 respiration than is returned in the form of car- 

 bonic acid, as shown by the experiments of 

 Dulong, Despretz, Edwards, and Treviranus, 

 (the latter makes the difference still greater in 

 fishes,) what, I repeat, becomes of the surplus 

 oxygen? Does it unite with the hydrogen ex- 

 haled from the lungs ; or with the blood, as sup- 

 posed by Edwards and others? That it com- 

 bines with hydrogen to form water, and con- 

 tributes largely to the evolution of animal heat, 

 would appear from the fact, that the temperature 

 of carnivorous animals is not inferior to that of 

 herbivora, although the former generate much 

 less carbonic acid ; whereas it has never been 

 proved that the combination of oxygen with the 

 blood is attended with an elevation of tempe- 

 rature, unless carbonic acid be formed. Ed- 

 wards maintains that carbonic acid is formed in 

 the general course of the circulation, because he 

 found it to be exhaled in notable quantities from 

 the lungs of frogs and young kittens, when con- 

 fined in vessels of pure hydrogen, and from 

 fishes placed in water deprived of oxygen. 

 Miiller also states, as the result of his own, and 

 the experiments of Bergman, that frogs exhale 



