88 
MANURES. 
if this is impressed on your mind, you will perceive 
tnat the chiefest things to be regarded in urine are, 
first, the circumstances which affect the quality and 
quantity; second, the best mode of promoting a 
change of urine to ammonia ; third, the time required 
for the process ; and fourth, the best mode of preserv¬ 
ing the ammonia, when formed. You will perceive, 
reader, that all along, I have endeavored to point out 
the principles on which manures act. If you go by 
general principles, then for a plain practical farmer, 
like yourself, with only chemistry enough to under¬ 
stand a few of its terms, it must be quite a thankless 
service, to point out to you in detail all the various 
things contained in urine. It would confuse you more 
than the names, ay, and hard ones too, which are 
given to the varieties of pears and apples. All you 
want to know is this, Does urine contain, as solid dung 
does, water, mould, and salts ? 
It does. The mould is so small a part, it may be 
left out of view. The salts are like those in the solid 
dung, mineral salts, and then we have the peculiar 
principle urea, which, for all practical purposes, may 
be called ammonia. We may then, with this division, 
present in a table the composition of the urine of 
various animals at one glance:— 
Cattle urine, per 100 lbs., 
Horse u u u 
Sheep “ 
Hog “ “ “ 
Human “ “ “ 
Water. 
Salts. 
Ammonia. 
92.62 
3.38 
4.00 
94.00 
5.03 
0.70 
96.00 
1.20 
2.80 
92.60 
1.76 
5.64 
95.75 
1.88 
2.36 
How cast your eye carefully over this table: the 
figures at once tell you the value of these different 
liquids. The last column gives the true value. The 
other salts vary much in quantity, and this affects the 
quality. The actual amount of ammonia in human 
urine and cattle dung is about the same; yet in actual 
