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XXIV. " Experimental Inquiry into the Composition of some 

 of the Animals fed and slaughtered as Human Food." 

 By J. B. LAWES, Esq., F.R.S., F.C.S., and J. H. GILBERT, 

 Ph.D., F.C.S. Received June 17, 1858. 

 (Abstract.) 



After alluding to the importance of the chemical statistics of 

 nutrition in relation to physiology, dietetics and rural economy, and 

 explaining that the branch of the subject comprehended in the pre- 

 sent paper is that of Animal Composition, the authors proceed in 

 the first place to state the general nature of their investigations, and 

 the manner in which they were conducted. 



To ascertain the quantitative relations, and the tendency of deve- 

 lopment, of the different parts of the system, the weights of the 

 entire bodies, and of the several internal organs, also of some other 

 separated parts, were determined in several hundred animals oxen, 

 sheep and pigs. 



To determine the ultimate composition, and in a sense the proxi- 

 mate composition also, of oxen, sheep and pigs, and to obtain the 

 results in such manner that they might serve to estimate the pro- 

 bable composition of the Increase whilst fattening, was a labour 

 obviously too great to be undertaken with a large number of ani- 

 mals. Those selected were a fat calf, a half-fat ox, a moderately 

 fat ox, a fat lamb, a store or lean sheep, a half-fat old sheep, a fat 

 sheep, a very fat sheep, a store pig, and a fat pig. 



It is to the methods and the results of the analysis of these ten 

 animals, to the information acquired as to the quantitative relation of 

 the organs or parts in the different descriptions of animal, and their 

 relative development during the fattening process, and to the appli- 

 cation of the data thus provided, that the authors chiefly confine 

 themselves in the present paper. 



The analyses of the ten animals were planned to determine the 

 actual and per-centage amounts of water, of mineral matter, of 

 total nitrogenous compounds, of fat, and of total dry substance in 

 the entire bodies, and in certain individual and classified parts of 

 the animals. The water and mineral matter were for the most part 

 determined in each internal organ, or other separated part. But, to 



