URINE. 



upon the nature of this solid matter, 

 and especially upon the rapid changes 

 which the organic part of it is known 

 to undergo. The preceding tahle ex- 

 hibits the average proportions of wa- 

 ter, and of the solid organic and inor- 

 ganic matters contained in the urine 

 of man and some other animals in 

 their hpalthy state, and the average 

 quantity voided hy each in a day. 



'• The numbers in the above table 

 show that the urine of the cow, esti- 

 mated by the quantity of solid matter 

 it contains, is more valuable tiian that 

 of any other of our domestic animals, ' 

 with'the exception of the pig. But 

 the quantity voided by the cow must 1 

 be so much greater than by the pig, | 

 that in annual value the urine of one j 

 cow must greatly exceed that of many 

 pigs. 



•• It might be supposed at first that ! 

 in all animals the quantity of urine 

 voided would have a close connexion 

 with the quantity of water which each 

 was in the habit of drinking. But this 

 is by no means the case. Thus it is 

 the result of experiment, that in man 

 the drink exceeds the urine voided 

 by about one tcnlh part only, while a 

 horse, which drank 35 lbs. of water 

 in 24 hours, gave only 3 lbs. of urine 

 during the same time ; and a cow, 

 which drank 132 lbs. of water, gave 

 18 lbs. of urine and 19 lbs. of milk.— 

 {Boussingaull.) 



" How very large a quantity of the 

 liquid they drink must escape from 

 the horse and the cow in the form of 

 insensible perspiration ! That this 

 should be very much greater indeed 

 than in man, we are prepared to ex- 

 pect from the greater extent of sur- 

 face which the bodies of these ani- 

 mals present. 



" Let us now examine more closely 

 the composition of urine, the changes 

 which by decomposition it readily un- 

 dergoes, and the effect of these chan- 

 ges upon its value as a manure. 



''Human Urine— The exact com- 

 position of the urine of a healthy in- 

 dividual, examined in its usual state, 

 w as found by Berzelius to be as fol- 

 lows : 



Water 9330 



Urea •*" * 



Z z z 2 



10 



J71 



(1-3 

 3-7 

 3-2 

 2-9 

 1-6 

 4.5 

 15 



M 



Uric acid 



Frt-e lactic acid, lactate of ammonia, and 

 aiiiinal niuMur iioi separable .... 



Mucu.s i)f ihe bluililer 



Sulphate of piitash 



Sulphate of sinla 



PliDsphale of soda 



Phiisphate of ammonia 



Coiimiou suit 



Sal-ainmuniac 



Phosphates of lime and magnesia, with 

 a trace of silica and of fluoride of cal- 

 cium 



lUOO-0 



"From what I have already had 

 occasion to state in regard to the ac- 

 tion upon living plants, of the sever- 

 al sulphates, phospiiates, and other 

 saline compounds mentioned in the 

 above analysis, you will see that the 

 fertilizing action of urine would be 

 considerable, did it contain no other 

 solid constituents. But it is to the 

 urea which exists in it in very much 

 larger quantity than any other sub- 

 stance, that its immediate and mark- 

 ed action in promoting vegetation is 

 chiefly to be ascribed. This urea, 

 which is a white, salt-like substance, 

 consists of, 



per cent 



Carbon 20-0 



Hydrogen ^'^ 



Nitrogen '^^^''^ 



O.xygeu 26-7 



100-0 



" It is. therefore, far richer in nitro- 

 gen than all other richly-fertilizing 

 substances. 



" But urea possesses this farther 

 remarkable property, that when urine 

 begins to ferment, it changes entirely 

 into carbonate of ammonia. Of the 

 ammonia thus formed, a portion soon 

 begins to escape into the air, and 

 hence the strong ammoniacal odour 

 of fermenting urine. This escape of 

 ammonia continues for a long period, 

 the liquid becoming weaker and weak- 

 er, and consequently less valuable as 

 a manure every day that passes. Ex- 

 perience has shown that recent urine 

 exercises in general an unfavourable 

 action upon growing plants, and that 

 it acts most beneficially after ferment- 

 ation has freely begun, but the longer 

 time we suffer to elapse after it has 

 , reached the npc state, the greater the 

 quantity of valuable manure wc per- 

 I mit to go to waste. 



821 



