ALLOTMENT SYSTEM. 99 



The third circumstance remarkable in the case was, that the 

 cows are fed in the stalls, and never turned out. The principal 

 food given them was clover, tares, or rye cut green ; the leaves 

 of mangel-wurzel, and, in the winter, turnips, mangel-wurzel, 

 carrots, &c., and straw. The cows were in good condition, and 

 though evidently not of a character to promise much milk, yet 

 the health of the animals was perfect. They were not selected, 



which can be kept in the same state of fertility by the excrements of a certain 

 number of horses, cows, and sheep. 



&quot; The course I have adopted in this inquiry has been, in the first place, to 

 ascertain the average quantity of food, both animal and vegetable, consumed by a 

 certain number of individuals in a given time, and from a knowledge of the com 

 position of such food to deduce the composition of the excrements, and afterwards 

 apply this to the composition of crops ; for it is now universally admitted that all 

 those elementary constituents which enter into the composition of plants or 

 animals, are primarily derived from the air or the soil, and that whatever be the 

 quantity of elementary constituents taken in the food of an adult man, in a given 

 time, the same quantity of these constituents will again be eliminated from his 

 system by the lungs, skin, kidneys, and intestines, in the same time. If, therefore, 

 we preserve the whole of the excretions made by an individual in a given time, 

 we preserve the whole of the elements of the food he has consumed in that time, 

 and, by applying these to land, should be able to produce again the same amount 

 of food in the form of corn and potatoes, together with an extra quantity of vege 

 table matter, which, being consumed by a growing animal, Avould yield an equiva 

 lent amount of flesh ; and these changes would be continued ad inftnitum. 



&quot; It fortunately happens that those constituents of food which are eliminated by 

 the lungs are derived solely from the atmosphere, and, as there is an inexhaustible 

 supply of these in the atmosphere, no restoration of them to a soil is required. 

 On the other hand, those eliminated by the kidneys and intestines, are derived 

 exclusively from the soil, and, consequently, require restoring, in order to main 

 tain its fertility.&quot; 



*****#* 



&quot; Thus we export from the fifty acres of wheat and barley, and the fifty acres 

 of green crops, by one hundred young lambs, forty yearlings, four young cows, 

 four calves, and two horses, the following quantity of those constituents of a soil 

 which enter into the composition of plants : 



Potash and soda, 780 Ibs. 



Lime and magnesia, 948 



Phosphoric acid, 1549 &quot; 



Sulphates and chlorides, 21 &quot; 



Silica, 450 



Metallic oxides, 8 &quot; 



Nitrogen, 2681 &quot; 



&quot; It will be seen from the tables of the constituents of food, that the ingredients 

 contained in the liquid and solid excrements of one hundred individuals, and the 



