200 
Value of Earth-Closet Manure. 
other chemists ; and, accordln? to an analysis made by Professor 
Wav, the solid matter which is obtained by its evaporation to a 
perfectly dry mass consists, in 100 parts, of: — 
*Orgaiiic matter 67*54 
Insoluble siliceous Biatter '09 
Oxide of iron '05 
Lime "61 
Magnesia '47 
Phosphoric acid 4'66 
Sulphuric acid '46 
Potash 1-83 
Chloride of potassium 5"41 
Chloride of sodium 18-88 
100-00 
* Containing nitrogen 19-43 
Equal to ammonia 23*60 
Unfortunately urine enters very rapidly into decomposition, 
giving rise to foul-smelling gaseous products of decomposition, 
and to volatile carbonate of ammonia ; and, on keeping, loses 
much of its most valuable constituent. The collection and pre- 
servation of urine, in consquence, is attended with practical diffi- 
culties, which are greatly enhanced by the trouble and expense 
of getting rid of the large proportion of water which urine 
naturally contains. For these reasons, all attempts to collect urine 
and to obtain from it a solid manure by evaporation have hither- 
to proved failures in an economical point of view. 
Fresh urine contains, on an average, only three per cent, of 
solid matter, and, according to Professor Way's analysis just 
quoted, consists of : — 
Water 97-000 
•Organic matter 2-026 
Insoluble siliceous matter '003 
Oxide of iron -002 
Lime 018 
Magnesia -014 
Phosphoric acid -040 
Sulphuric acid -014 
Potash -055 
Chloride of potassium -1^2 
Chloride of sodium -566 
100-000 
• Containing nitrogen -58 
Equal to ammonia -71 
Notwithstanding this large proportion of water, the amount of 
solid matter in the urine voided in a day is just about one-third 
greater than the amount of dry matter in the daily solid evacuations. 
It is not easy to calculate with great precision what is the total 
