OF ANIMALS FED AND SLAUGHTERED AS HUMAN FOOD. 
877 
ruminants, whilst figures obtained in the same way do not indicate a similar result in 
the case of the pigs. In the ashes of the pigs the phosphoric acid is considerably in 
excess of the quantity required to give tribasic phosphates with the whole of the lime 
and magnesia; the former of which is in relative deficiency. The result is that, upon 
the whole ash of the pigs, the figures show a deficiency rather than an excess of base, 
especially in the case of the fatter animal, 
The consistency of the result with the ruminants, and again the consistency, but in 
the opposite direction, with the pigs, would lead to the conclusion that the indication 
is not simply due to the conditions of incineration, or to error of any kind. As bearing 
upon the point it is in the first place to be borne in mind that fluorine was not deter¬ 
mined in the ashes ; but certainly its amount would not be sufficient to turn the 
scale. Then there is the question whether organic acid salts, and carbonates existing 
as such, are adequately represented by the amount of carbonic acid determined in the 
ashes ; and there is the further question whether sulphuric acid, and possibly phos¬ 
phoric acid, may have been reduced, or sulphuric acid or chlorine expelled, in the 
burning. 
According to direct experiments of Way and Ogston (Jour. Roy. Ag. Soc. Eng., 
vol. ix.), sulphuric acid is expelled by silica, but not by acid phosphates, in incinera¬ 
tion. They conclude, however, that there is no loss of phosphoric acid; nor of 
chlorine in careful burning. Others have concluded that the expulsion of both sul¬ 
phuric acid and chlorine is dependent both on the character of the ash, and on the con¬ 
ditions of the incineration ; and in this Mr. Richter’s experience leads him to concur. 
On the other hand it has to be considered whether the phosphoric acid and sulphuric 
acid found in the ashes are not in excess of the amounts existing as such in the 
substances burnt. On this point Way and Ogston and others have long ago con¬ 
cluded that sulphur is oxidated in incineration in very variable amounts according 
to circumstances ; and quite recently Grouven has concluded that sulphur is converted 
into sulphuric acid in the ordinary methods of incineration in free air, and that under 
the same circumstances sulphates existing in the organic substance burnt are not 
reduced. Grouven concludes that about half of the sulphur may be converted into 
sulphuric acid in the burning. Again, according to Dr. Yoelcker’s experiments (Rep. 
Brit. Ass., 1857, abstract, p. 60) at any rate a large proportion of the sulphur and 
phosphorus is not oxidated in the incineration; and Fresenius has obtained similar 
results so far as phosphorus is concerned. Lastly, with regard to the question 
whether sulphuric acid is reduced by charcoal in the burning, Mr. Richter has found 
in some parallel experiments with wheat grain ashes high sulphuric acid with high 
charcoal, and low sulphuric acid with low charcoal; but on the other hand he has not 
observed sulphuretted hydrogen on dissolving such ashes in hydrochloric acid. 
It may be stated that the foregoing observations as to the relation of base and acid 
in the ashes apply generally to those of the collective carcass, of the collective offal, 
and of the entire bodies of the different descriptions of animal. But where, as in the 
5 u 
MDCCCLXXXIII. 
