28 



Production of Butter. 



28 lbs. of hay contain . . . 0' 436 lbs. of fat. 

 2^ „ oatmeal „ . . . 0-050 „ 

 8 „ beans . . , 0'056 „ 



In the food 0-542 



The milk of the evening amounted to 10 -34 lbs., and contained 0*4 lbs. of 

 butter ; that of the morning to 11 'Gllbs., and contained 0*5 lbs. of butter ; the 

 whole amounting to 0-9 lbs., of which only 0*542 lbs. could possibly have been 

 furnished by the food, assuming that the fat in the food could only be converted 

 into butter. 



3. The cow received on the 4th day 14 lbs. of hay, 8 lbs. of beans, and 24 

 lbs. of potatoes. 



14 lbs. of hay contain . . 0*218 lbs. of fat. 



8 „ beans „ . . . O-056 „ 

 24 „ potatoes „ . . . 0-072 „ 



In the food 0'346 



The evening's milk amounted to 12*9 lbs., and contained 0-86 lbs. of butter; 

 that of the morning to 10-32 lbs., and contained 0- 50 lbs. The cow, therefore, 

 furnished during the day 1-36 lbs. of butter. The fat in the food only 

 amounted to 0-346 lbs., therefore 1*064 lbs. must have been obtained from 

 other sources 



4. On the 5th day the cow received 14 lbs. of hay, and 30 lbs. of potatoes. 



14 lbs. of hay contain . . . 0*218 lbs. of fat. 

 30 „ potatoes „ . . .0-090 „ 



In the food 0-308 



The milk of the evening amounted to 13 -18 lbs., and contained 0*606 lbs. of 

 butter : that of the morning to 12*20 lbs., containing 0-597 lbs. of butter. The 

 cow, therefore, furnished 1-203 lbs. of butter. The fat in the food amounted 

 only to 0*308 lbs. ; hence 0-895 lbs. of butter must have been produced from 

 other sources. 



From the preceding calculations it is presumed that the excess 

 of butter, beyond that contained in the food, has been produced 

 by a separation of oxygen from the elements of the unazotised 

 ingredients of the food, such as starch and sugar, in the manner 

 pointed out by Liebig. 



In the preceding experiments there are several variations ; this 

 will ever be found the case where so much depends upon the 

 health and disposition of the animal, over which man can possess 

 little, if any control ; many circumstances may pass unheeded by 

 the observer, which may powerfully influence the character of the 

 milk. It will be seen that in the milk of the first day there is 

 a small amount of butter. The cow had been exposed in the 

 field during the day, and hence required a greater quantity of 

 unazotised food to support the heat of her body than would have 

 been necessary had she been protected from the cold ; but in the 



