526 PHYSIOLOGY AT THE FARM. 



same amount of nitrogen, while in these 120 grains of urea 

 there are also of 



Carbon, . . 24 grains. 



Hydrogen, . 8 



Nitrogen, . . 56 



Oxygen, J32 



120 



If enough of oxygen be supplied to abstract a sufficient 

 amount of the carbon and of the hydrogen, then the 395 grains 

 of proteine will pass into 120 grains of urea. The residual 

 carbon is 192 grains, requiring 256 grains of oxygen for its 

 conversion into 448 grains of carbonic acid. The residual 

 hydrogen is 19 grains, requiring 152 grains of oxygen for its 

 conversion into 171 grains of water; but as the oxygen in the 

 395 grains of proteine exceeds that in the 120 grains of urea 

 by 64 grains, there will not be required jointly for the reduc- 

 tion of the proportions of carbon and hydrogen 256 + 152, or 

 408 grains, but only 408 64 grains, or 344 grains ; that is to 

 say, 344 grains of oxygen would be consumed for every 395 

 grains of proteine or muscular substance disintegrated during 

 muscular contraction, while 448 grains of carbonic acid and 

 171 grains of water would be generated. If four times 120 

 grains of urea are excreted in 24 hours, then 1580 grains of 

 proteine would be disintegrated in that period, while 1792 

 grains of carbonic acid and 684 grains of water would be pro- 

 duced ; that number of grains of carbonic acid containing 488 

 grains of carbon, and that quantity, when burnt with oxygen, 

 affording to 16,143 ounces of water one degree of Fahrenheit, 

 or one degree of Fahrenheit to 1009 Ib. of water ; but 1009 X 

 772 = 778,948 foot-pounds, that is, the combustion of 488 

 grains of carbon with oxygen represents a mechanical effect 

 equal to the raising 778,948 Ib. to the height of one foot. If 

 8 times 120 grains of urea are excreted, then there would be 

 soluble that number of foot-pounds, or 1,557,896. 



