of the Fat of the Animal Body. 447 



Experiments 2 & 3. — In both these experiments the pro- 

 portion of nitrogenous substance in the food was very large ; 

 the relation of non- nitrogenous to one of nitrogenous substance 

 being in Exp. 2 little more than half, and in Exp. 3 little more than 

 one-third as much as is usual in the recognized good fattening 

 food of the animal. In Exp. 2 the food consisted of bran, 

 bean and lentil-meal, and Indian-meal, each given separately, 

 and ad libitum ; and in Exp. 3 of an equal mixture of bean and 

 lentil-meal only, given ad libitum. 



'^Experiments 4 & 5. — In Exp. 4 the food consisted of In- 

 dian meal only, and in Exp. 5 of barley-meal only, in each case 

 given ad libitum. Barley- meal is undoubtedly the most approved 

 staple fattening food of the pig ; and the result was, that in 

 both these experiments the proportion of non-nitrogenous to 

 nitrogenous substance in the food was very nearly, though 

 rather higher than, the average in that which is recognized as 

 the most appropriate fattening food of the animal. 



Experiments 6, 7, 8, & 9. — The peculiarity of this series 

 was, that the food contained less ready-formed fat than was the 

 case in either of the other experiments, and that a large pro- 

 portion of the non-nitrogenous substance supplied was in the 

 form of either pure starch, pure sugar, or both. In Exps. 6, 

 7 & 8, a fixed quantity of lentil-meal and bran (averaging 

 nearly 3| lbs. lentil-meal and about 9 ounces bran) was given 

 per head per day, and, in addition, in Exp. 6 sugar, in Exp. 7 

 starch, and in Exp. 8 sugar and starch, each separately, ad 

 libitum. In Exp. 9 lentil-meal, bran, sugar, and starch were 

 each given separately, ad libitum. 



The figures given in the Table show that the increase in 

 weight was in no case less than 50, and in several nearly, and 

 in one more than 100 per cent., upon the original weight of 

 the animals, the amounts ranging from 51 3 to 68*9 per cent, 

 when the experiment extended over eight, and from 85*4 to 

 106*8 per cent, when it extended over ten weeks. 



The determined or estimated amount of fat stored up in the 

 increase was also in all cases very large, amounting to 63 per 

 cent, of the total increase in Exp. 1, in which it was experi- 

 mentally determined, and calculated to be even more than this 

 in several of the other cases. The tendency to error in the cal- 

 culations would, however, be to give the proportion too low in 

 Exps. 6, 7, 8 & 9, which were conducted over a period of 

 ten weeks, and in which the proportion of increase upon the 

 original weight was very high, and to give it too high in Exps. 

 2, 3, 4 & 5, conducted only over eight weeks, but more espe- 

 cially in Exps. 2 & 4, in which the proportion of increase 

 upon the original weight was comparatively small. The rang 



