368 AGRICULTURAL CHEMISTRY 



fat pig and most in the half -fat ox. The offal parts, as 

 the head, feet, tail, hair, wool, and horns, are quite rich 

 in nitrogen but not so rich as the flesh. Beef -yielding 

 animals, on the whole, contain rather more nitrogenous 

 compounds than sheep, which in turn contain more than 

 pigs. A large amount of the nitrogenous compounds of 

 sheep and lambs is present in the wool (50 to 55 per 

 cent). About 75 per cent, of the carcass of the sheep is 

 consumed as food ; thus it will be seen that much less 

 than half of the total nitrogen is really made use of as 

 human food. Of the fattened pig, about three-fourths of 

 the nitrogenous compounds are in the edible carcass. 

 From 6 to 7 parts are in the bone, and about one- quarter 

 is in the offal. About 8 per cent, of the nitrogenous 

 compounds of the offal and a little over three- fourths of 

 the total nitrogenous compounds of the pig are consumed 

 as food. About two-thirds of the entire nitrogen of the 

 calf and steer are in the butcher's carcass, and about 

 12 per cent, is in the bones. From 5 to 7 per cent, of 

 the nitrogen of the offal parts and about 60 per cent, of 

 the total nitrogen of the steer are utilized as human food. 

 In the table of relative composition of animal bodies, 

 it will be noted that the mineral matter increases and de- 

 creases with the nitrogenous matter. In the carcasses of 

 all animals, it will be observed that the amount of fat al- 

 ways exceeds the amount of nitrogenous matter, except 

 in the case of the lean calf. In the bodies of animals in 

 good condition, there is usually twice as much fat as dry 

 protein. The following table is from the extensive work 

 of Lawes and Gilbert. 



