1] 



LESSONS m CHEMISTRY. 



which these liquids would produce when applied to the fields 

 must therefore be very different. The urine of man and of 

 the pig is specially adapted to promote the growth of our 

 seed-crops, and that of the horse and cow for the root-crops, 

 which require to be supplied with alkalies.* 



167. To fix upon your minds what I have stated respecting 

 the loss which our farmers experience by neglecting to econo- 

 mise the liquid excrements of the domestic animals, you 

 have merely to calculate, from the information which I have 

 given, the value of the fertilizing materials which are annually 

 wasted, on almost eveiy farm in this country. Thus, a 

 fanner who keeps three cows and one horse, and col- 

 lects merely the solid dung, allowing the urine to escape 

 into the drains, loses annually in the cow urine (165) 

 3069 lbs. and in that of the horse, 89 lbs. ; in all, upwards 

 of 28cwt. of dry fertilizing matter, equal in value to the best 

 Pemvian guano, and which at the usual price of that substance 

 would be worth £14, and be capable, without the addition of 

 any other manure, of keeping seven acres of land in the 

 most fertile condition. 



168. Solid excrements of the domestic animals. — The dung 

 of the cow and horse, and of the other domestic animals, is 

 found to differ materially from the urine in composition ; while 



* Mr. M'Lean, in the Transactions of the Highland and Agricultural 

 Society/, gives the following report of the comparative value of urme, 

 moss saturated with urine, and subsoil saturated with urine, in an 

 experiment upon the hay crop of 1842. 



