462 
On the Composition of Oxen, Sheep, and Figs. 
Takino; the mean composition of tlie six animals assumed to 
be fit for the butcher — namely, the fat calf, the fat ox, the fat 
lamb, the fat sheep, the very fat sheep, and the fat pig — we have, 
in round numbers, 3 per cent, of mineral matter, 13 per cent, of 
dry nitrogenous compounds, and 33 per cent, of fat, in their fasted 
live-weight, = 49 per cent, total dry substance, exclusive of that 
of the contents of stomachs and intestines. 
All the experimental evidence conspires to show that the so- 
called " fattening " of animals is properly so designated. Even 
"/caw" animals have been seen to contain more fat than nitro- 
genous compounds. After the feeding or fattening process, the 
percentage of the total dry substance of the body is considerably 
increased ; and the fatty matter accumulates in much larger 
pi'oportion than the nitrogenous compounds. It is obvious, there- 
fore, that the increase of the fattening animal must contain a 
lower percentage of nitrogenous substance, and a higher one of 
both fat and total dry substance, than the entire body of the 
slaughtered animal. Moreover, with the comparatively small 
increase in the amount of bone, and the small accumulation of 
soft nitrogenous parts, we should expect the percentage of 
mineral matter also to be very small in the increase of the fat- 
tening animal. 
IV. Estimated Composition of the Increase of Fattening 
Oxen, Sheep, and Pigs. 
It is obvious that, provided we knew the composition of an 
animal when it weighed any given weight — say 100 lbs. — and 
again, when, after fattening, it had reached another weight — 
say 150 lbs. — it would be a very easy matter to calculate the 
actual and the percentage composition of the 50 lbs. that had 
been gained. The practical difficulty rests in the fact that we 
cannot know the exact composition of a fattened animal at the 
time it was put upon fattening food, or when it had reached any 
given previous weight. Exercising a careful judgment on the 
point, we have applied the composition of the respective animals 
analysed in the lean condition, to the known weights of numbers 
of animals of the same description, when assumed to be in a 
similar lean condition. In like manner the composition of the 
fat animals analysed has been applied to the weights of the same 
animals after being fattened. 
In the manner here described, the composition of the increase 
of 98 fattening oxen, 349 fattening sheep, and 80 fattening pigs 
— each divided into numerous classes, according to breed, con- 
dition of maturity, or descripti(m of food — has been calculated. 
The composition of the increase, so calculated, together with some 
