'38 ELEMENTS OF ' 



From the foregoing analysis it would appear, that 

 1000 pounds of human uiine contain no less than 68 

 pounds of dry feriilizing matter of the richest quahty, 

 worth, at the present rale of selhng artificial manures 

 in this country, (England,) twenty shillings per hundred 

 weight. Suppose we say that the liquid and solid ex- 

 crements of one human being amount on an average to 

 a pound and a half daily, then in one year they will 

 amount, to 547 pounds ; which, at the rate of three per 

 cent, of contained nitrogen, would yield sixteen pounds 

 of that material for the land — a quantity sufficient to 

 supply enough for eight hundred pounds of wheat, rye, 

 or oats, or for nine hundred pounds of barley. As each 

 person in reality voids at least one thousand pounds or 

 pints of urine in a year, the national waste incurred in 

 this form amounts, at the above valuation, to twelve 

 shillings a head upon every individual of the whole 

 population. And if five tons of farm-yard manure per 

 acre, yearly, will keep a farm in good order, four hun- 

 dred weight of the solid matter of urine would probably 

 have an equal effect ; in other words, the excrements of 

 a single individual are more than sufficient to yield the 

 requisite nitrogen to an acre of land, in order to enable 

 it (with the assistance of the nitrogen absorbed naturally 

 from the atmosphere) to produce the richest possible 

 yearly crop. Every town and farm might thus supply 

 itself with the manure, which, besides containing the 

 most nitrogen, contains also the most phosphates ; and 

 if an alternation of the crops were adopted, they would 

 be most abundant. By using at the same time bones 

 and wood-ashes, the excrements of animals might be 

 complettly (hspcnsc d with. ISo that the artificial, min- 

 eral, or chemical manures are no imj)crfect subi^titute^', 

 if a})plied judiciously. 



The urine alone di^-chargcd into rivers or sewers by a 

 town population of lO.Odll inhabitants, would supply ma- 

 nure to a farm of 1500 acres, yielding a return of 4500 

 quarters of grain, or an e((uivalent produce of other crops. 

 8o mucli value is attached to human excrements by the 

 Chinese, that the laws of the country forbid that any of 



