RESPIRATION. 



Milk, 



Urine, 



Faeces, 



Dry. 



18-7 Ibs. composed of 2-54 Ibs. -f 



18-13 . . 2-12 + 



62-63 . . 8-819 + 



Water. 



16-16 

 16-01 

 54-81 



86-98 



Total, 13-479 

 Specific gravity of milk, . . 1*035 



Specific gravity of urine, . . 1 -034 

 All of these dry substances were subjected to an ultimate analy- 

 sis, and found composed as follows : 



Potatoes. Hay. Milk. 

 Ibs. Ibs. Ibs. 



1-387 

 0-218 

 0-102 

 0-709 

 0-124 



9-08 14-22 2-54 2-111 8-818 



The cow neither gained nor lost in weight during the experi- 

 ment. The carbon taken in exceeded that in the dejections by 

 nearly 5 Ibs. Therefore 5 Ibs. of carbon must have been dis- 

 charged by respiration and transpiration , The hydrogen taken 

 in exceeded that in the dejections by nearly half a pound, which 

 must have been thrown out in the form of water by respiration 

 or transpiration. The difference in the quantity of azote taken 

 in and given out is so small that it may be only an error in the 

 experiment. But, as the quantity taken in is rather greater than 

 that given out, we have no reason to conclude that azote is ab- 

 sorbed by the lungs. 



Boussingault made a similar experiment on a horse for three 

 days, during which he neither gained nor lost weight. The food 

 per day was, 



Hay, . 

 Oats, 



Water, . 

 The dejections per day were, 



Urine, 



Fasces, 



16-54 Ibs. 



4-87 

 266-11 



2-928 Ibs. sp. gr. 1-064 

 3-45 



The composition of food and dejections, 



