ON THE MILK OF THE COW. 325 



The casein was obtained directly by employing skimmed milk of the same milking, coagu- 

 lating it by a drop of sulphuric acid, straining off the whey, and lightly washing the casein 

 with cold water. As I obtained by this method it agreed with that obtained by the method I 

 had usually employed. 



I infer from this analysis that oil-cake increases the amount of butter ; or at least, the infe- 

 ference that it is not dimmished, is safe. It must however be recollected that it followed im- 

 mediately the brewers' grains, which had a fine effect, and that when the oil-meal was com- 

 menced the cow was giving nearly if not quite her full amount of milk ; or in other words, 

 she had reached her full capacity for secreting butter and cheese : the casein had rather di- 

 minished. Oil-cake is fed only sparingly to cows in Albany ; brewers' grains are so cheap, 

 and being regarded too as favorable to the production of milk, they have become almost ex- 

 clusively the food of the cow. The value of oil-meal is established as a fattening substance, 

 and one that is adapted to all the wants of the animal economy. It is rich in albumen or ni- 

 trogen, and is, therefore, fitted to supply the waste which is going on in the muscular tissues : 

 it is, by far, richer in oil than Indian corn, and is, therefore, fitted to sustain the temperature 

 fully up to the normal standard. Its effects may have been modified by the extreme cold 

 which prevailed during the whole time the experiment lasted. It should have produced more 

 casein, inasmuch as it is rich in albumen. The ash is rich in phosphates, and is hence adapted 

 to supply bone and other solids which require phosphates, as most of the albuminous bodies do. 

 The ash is never pure but intermixed with sand, which adheres to the cake. 



The composition is as follows : 



Sand and silex, 48*50 



Earthy phosphates, 36'60 



Carbonate of lime, 0"50 



Magnesia ' 40 



Potash, 10-96 



Soda 2-12 



Chlorine, trace. 



99-08 



I made at this time an organic analysis of oil-cake, for the purpose of obtaining the quantity 

 or percentage of albumen and oil : it is known to be rich in both ; thus I found 100 grains to 

 contain, 



Water 9-00 



Mucilage 30-92 



Albumen, 19-70 



Oil 12-25 



Fibre 18-25 



Sand and ash, 10-10 



