COMPOSITION OF ANIMAL BODIES. 25 



of the useful and the waste parts of the animal, and can 

 be studied with profit, as showing how the parts of the 

 animal change as the process of fattening goes on.* 



In explanation of this table : The carcass is that part of 

 the animal consumed as food. The offal .is made up of 

 those parts not consumed as human food, and embraces 

 skin, feet, head and all the internal organs, except the kid- 

 ney and kidney fat. The relative proportion of fat in the 

 carcasses analyzed is given ; but the nitrogenous matters 

 are found in large proportion in the offal, so that the rela- 

 tive proportions of the constituents of the whole body -are 

 considered. In a fat and fully-grown animal, there is 49 

 per cent, of water, 33 per cent, of dry fat, 13 per cent, of 

 dry nitrogenous matter muscles separated from fat, hide, 

 etc., and 3 per cent, of mineral matter. In the lean animal 

 the average proportion is 54 per cent, of water, 25 per 

 cent, of dry fat, 17 per cent, of dry nitrogenous matter, 

 and 3^- per cent, of mineral substances. 



This table contains a summary of the most important 

 experiments ever carried out to ascertain the facts here 

 stated. This clearly shows how a lean animal exchanges 

 water for fat, and how the animal may be improving most 

 profitably without gaining much in weight by a substitu- 

 tion of fat for water. He shows that during the last stages 

 of fattening the. gain may consist of 75 or more per cent, 

 of dry substance. 



We place this table in the first chapter that it may be 

 easy of reference in illustration of the feeding experi- 

 ments given in the progress of the work. 



We also print here an extensive table of proportions of 

 the various parts of cattle, sheep, and swine, from the Ger- 

 man of Wolff, for a translation of which we are indebted 



* " Experimental Inquiry into the Composition of some of the Animals 

 Slaughtered as Human Food." By John Bennet Lawes, F. R. S., F. C. S., 

 and Joseph Henry Gilbert, Ph. D., F. C. S. Philosophical Transactions 

 of the Royal Society, Part II., 1860. 



