5900 
is greater in amount than what existed. origi- 
nally in their food; so that as they likewise 
breathe out water in the form of vapour from 
their lungs, and evaporate it through the skin, 
they must produce water chemically from oxy- 
gen and hydrogen during the process of diges- 
tion. Their urine, on account of its small amount, 
is never collected and used by itself, but is al- 
ways taken up by the litter, and applied to the 
land along with the solid excrements; and 
though not belonging to circumstances to which 
much attention is devoted in agriculture, it is 
nevertheless interesting to learn its component 
parts. Sprengel several times submitted it toa 
superficial chemical analysis, and found that it 
is more abundant in salts than the urine of the 
cow, without, however, containing so many sub- 
stances possessing nitrogen; and that 100,000 
parts by weight of the fresh urine of sheep kept 
at grass, and which, when tested, was found to 
indicate neither acid nor alkaline properties, 
contained 96,000 parts of water, 2,800 of urea, 
along with some albumen and colouring matter, 
and 1,200 of salts of potash, soda, lime, and mag- 
nesia, with traces of silica, alumina, iron, and 
manganese. Sheep urine, therefore, contains 
4 per cent. more water than cattle urine; but 
possessing a tolerable quantity of urea, it passes 
quickly into decomposition, and developes, in 
consequence, much ammonia,—a fact which ex- 
plains the occurrence of the strong ammoniacal 
smell in the places where sheep are kept; this 
smell being much increased, however, by the 
ammonia likewise produced in the decomposition 
of the solid excrements, which contain much ni- 
trogen, and by the exhalation of a certain degree 
of ammonia through the skin of the sheep. The 
ammonia thus formed naturally evaporates the 
sooner when the manure is deficient in moisture, 
which would retain it. Hence it is obvious how 
great a quantity of the ammonia of this very 
valuable manure is lost in the ordinary ma- 
nagement of the dung when sheep are kept in 
houses. 
Horses drink less water than cattle; and as 
they lose at the same time much moisture by 
evaporation through the skin, they also dis- 
charge much less urine. According to Fourcroy 
and Vauquelin, their urine contains 94 per cent. 
of water, 0°7 of urea, 2°4 of benzoate of soda, 0°9 
of carbonate of soda, 1:1 of carbonate of lime, 
and 0:9 of muriate of potash. This analysis, 
however, as can be easily proved, is not quite 
correct ; for it ought to comprise small propor- 
tions of mucus, albumen, magnesian salts, phos- 
phate of lime, colouring matter, and some other 
less important substances. Since horse urine 
contains much less nitrogenous matter than cat- 
tle urine, it has much less value as a manure; 
and on account of its small amount it is never 
worth the trouble of being collected and em- 
ployed by itself, but is brought to the soil in 
mixture with the solid excrement and litter. 
URINE. 
The circumstance of the urine of the horse con- 
taining so few substances united with nitrogen 
explains to us how it happens that in the solid 
excrements there are found so many of these 
bodies. The nitrogen derived by the body from 
the food is again, however, partly lost by evapo- 
ration through the skin, combined with hydro- 
gen, and forming ammonia; the perspiration of 
the horse always having, from this cause, an am- 
moniacal odour. 
The urine of hogs is more copious than that of 
any other domesticated animals, in consequence 
of their using a comparatively large quantity of 
liquid food; and it acquires in putrefaction the 
most intolerable odour, occasioned by a peculiar 
volatile substance, at present imperfectly known ; 
and it is this substance probably which commu- 
nicates the unpleasant flavour to esculent roots. 
According to Sprengel’s investigation, 100,000 
parts, by weight, of the urine of pigs fed on corn 
offal, consisted of 92,600 of water, 5,640 of urea, 
with a very little mucus, albumen, and colour- 
ing matter, and 1,760 of salts, as common salt, 
muriate of potash, gypsum, carbonate of lime, 
and sulphate of soda. It results from this ana- 
lysis, that the urine of the pig contains rather a 
smaller proportion of water than the urine of 
cattle, and 1 per cent. more of urea; and this 
circumstance perfectly explains the reason of its 
being more caustic in its fresh state than that 
of cattle, a larger supply of ammonia being cre- 
ated out of the greater amount of urea; so that 
before the urine of the pig can be applied with 
propriety to growing plants, it must have under- 
gone putrefaction. To prevent, however, an 
useless escape of the ammonia, it will be very 
advisable to dilute it with a good deal of water 
before exposing it to putrefy, or to proceed with 
it as already recommended in the case of cattle 
urine. The ill effects of pig urine, not properly 
putrefied, are commonly ascribed to the presence 
of a peculiar acidity; but they arise from no 
other cause than the caustic ammonia. When 
this urine is conducted, as is generally the case, 
into the manure pit, a great loss of manuring 
matter, in the form of gas, always takes place ; 
and it is, therefore, the best plan to convey it by 
itself into a tank, and mix it with a large quan- 
tity of water. For this plan, however, a judi- 
cious arrangement of the sty is necessary; and, 
if situated near the cattle-stalls, the urine of the 
pig can be led to that of the cattle, and there 
allowed to putrefy. It is maintained that, when 
the urine of the pig gets into a pond containing 
fish, it kills them: should this actually be the 
case, the effect would probably be occasioned by 
sulphuretted hydrogen, resulting from the de- 
composition of gypsum, and constituting a gaseous 
poison, to the action of which fishes are very 
sensible, and of which a very small quantity is 
required to kill them instantly. 
Human urine contains rather more water than 
that of cattle; and as it also holds less urea and 
