350 REPORT—1852. 
It may be observed, that in the case of the experiment with this single pig, 
the amounts of nitrogenous and non-nitrogenous constituents required to 
produce a given amount of increase—though nearly the same as the averages 
of the 24 pens, as given at the foot of Table VII.—were greater, than in many 
of the cases with the better foods. Hence, the quantities of the various con- 
stituents, represented in Table IX. as stored up in this pig for 100 of each of 
them consumed, are less than they would be in many of the other experi- 
ments, We believe, however, that the figures in the Table (IX.) may be trusted 
in their general indications; and attention may therefore be called in passing 
to the fact, that for 100 of each consumed, there is of the total dry substance 
little more than 15 stored up in the animal; of the mineral matter, little 
more than 2 per cent.; and of the nitrogenous constituents, about 83rd per 
cent. 
Again, a glance at the Table shows how very much Jarger is that propor- 
tion of every constituent of the food—excepting fatty matter—which was 
expired, perspired or voided, 7. e. which was expended in merely keeping in 
working order the living mechanism, than that which is stored up in the 
animal as increase. Of fat, however, it appears that there was nearly four 
times as much stored up in the animal, as there was of fatty matter ready 
formed in the food. There was then, in this experiment, a considerable 
formation of fat in the animal body. : 
As is seen in the Table (IX.), for every 100 lbs. of gross dry substance 
consumed as food, only about 15 lbs. were stored up in the animal; and about 
85 lbs. expired, perspired or voided. It may be convenient here to show in a 
tabular form, the composition of this 15°04 of total dry increase obtained by 
the consumption of 100 of total dry matter as food. 
Table X. 
Mineral. matter .c.scsssseeeesssecess 0:09 
Nitrogenous substance ............ 1-67 
Non-nitrogenous substance (fat)| 18°28 


Total AnGrease ws ee sesh ts 15:04 
Expired, perspired or voided ... 61°96 





_ 
Total dry matter consumed ,..... 100-00 


It must not be concluded, however, that only 15 per cent. of the dry sub- 
stance of the food was employed in the production of the 15 parts stored up 
in the fat pig. Thus, in Table X. we see, that, of the 15°04 of gross dry 
increase produced from 100 of gross dry food consumed, 13°3 were fat; and 
from Table LX. we learn, that only one-fourth of this fat could have been 
derived from fatty matter already formed in the food. As then only one- 
fourth, or about 3°3 parts of the 13°3 of pure fat, was already formed in the 
food, about 10 parts out of the 15 of dry animal substance produced, would 
be fat formed in the body from some other constituents. We may perhaps 
safely reckon, that at least 25 parts of starch, or the other non-nitrogenous 
compounds of food, would be required for the formation of one part of fat. 
It is true, that less than 24 of starch, &c. would contain all the constituents 
of one part of fat; but when we consider, that in the conversion of the 
starch series of compounds into fat a large quantity of oxygen is eliminated, 
which we may assume would not leave the body except in combination with 
matters that would otherwise serve the respiratory process, it would seem 
probable, that more than 25 parts of other constituents of food would be ex- 

