MUCH CARBON. 73 



combined, in the form of urea, 3 oz., and in the form 

 of hippuric acid, 3| oz., of carbon. 



Without going further into the calculation, it will 

 readily be admitted, that the volume of air inspired and 

 expired by a horse, the quantity of oxygen consumed, 

 and, as a necessary consequence, the amount of car- 

 bonic acid given out by the animal, is much greater than 

 in the respiratory process in man. But an adult man 

 consumes daily about 14 oz. of carbon, and the deter- 

 mination of Boussingault, according to which a horse 

 expires 79 oz. daily, cannot be very far from the truth. 



In the nitrogenized constituents of his food, therefore, 

 the horse receives rather less than the fifth part of the 

 carbon which his organism requires for the support of 

 the respiratory process ; and we see that the wisdom 

 of the Creator has added to his food the fths which are 

 wanting, in various forms, as starch, sugar, &c. with 

 which the animal must be supplied, or his organism will 

 be destroyed by the action of the oxygen. 



It is obvious, that in the system of the graminivora, 

 whose food contains so small a proportion, relatively, 

 of the constituents of blood, the process of metamor- 

 phosis in existing tissues, and consequently their resto- 

 ration or reproduction, must go on far less rapidly than 

 in the carnivora. Were this not the case, a vegetation 

 a thousand times more luxuriant than the actual one 

 would not suffice for their nourishment. Sugar, gum, 

 and starch, would no longer be necessary to support life 

 in these animals, because, in that case, the products of 

 the waste, or metamorphosis of the organized tissues, 

 7 



