13.04 7.00 ... 25.0 7.72
Phosphate of soda ... 19.00 ... ... ...
Phosphate of lime }
Phosphate of magnesia } ... 8.80 ... ... 0.70
Chloride of sodium 6.94 53.10 0.30 14.7 32.01
Chloride of potassium ... trace ... ... 12.00
Silica 0.55 ... 0.35 ... 1.06
Oxide of iron and loss 1.09 ... 0.77 ... ...
------ ------ ------ ------ ------
100.00 100.00 100.00 100.00 100.00

Human urine has been accurately examined by Berzelius, although his
estimate of the proportion of urea is generally admitted to be above the
average. His analysis gives the following numbers:--

Natural. Dry Residue.
Urea 3.010 44.70
Lactic acid, lactate of ammonia,} 1.714 25.58
and extractive matter }
Uric acid 0.100 1.49
Mucus 0.032 0.48
Sulphate of potash 0.371 5.54
Sulphate of soda 0.316 4.72
Phosphate of soda 0.294 4.39
Biphosphate of ammonia 0.165 2.46
Chloride of sodium 0.445 6.64
Muriate of ammonia 0.150 2.46
Phosphates of magnesia and lime 0.100 1.49
Silica 0.003 0.05
Water 93.300
------- ------
100.000 100.00

Among the special organic constituents of the urine are three
substances, urea, uric acid, and hippuric acid, which are of much
importance in a manurial point of view. The first of these is found in
considerable quantity in the urine of all animals, but is especially
abundant in the carnivora. Uric acid is found only in these animals, and
is the most remarkable constituent of the excrement of birds, serpents,
and many of the lower animals. Hippuric acid is most abundant in the
herbivora. These substances are all highly nitrogenous. They contain--

Urea. Uric Acid. Hippuric Acid.
Carbon 20.00 36.0 60.7
Hydrogen 6.60 2.4 5.0
Nitrogen 46.70 33.4 8.0
Oxygen 26.70 28.2 26.3