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Moncy-valac of Niyht-Soil and oilier Manures. 
VIII. — The Moncij-mlue of Nujhi-Soil and of other Manures. 
By P. H. Freiie. 
Whatever be the issue of the struggle between earth and watei* 
(as indicated in the preceding paper) for taking under their pro- 
tection that Avhich is called " night-soil," it is essential that the 
value of the substances with which they propose to deal should 
be well investigated and established ; yet on this question ardent 
reformers and scientific chemists are at the present moment much 
at variance. The former, basing their calculations on the cost of 
maq's food and remarking the very high value assigned to the 
manurial virtues of some principal cattle-foods, produce esti- 
mates Avhich, although apparently framed with great moderation 
and due allowance, may be still wide of the mark because they 
are built on an unsound hypothesis. 
In truth, the cost of an article as food is hardly any criterion 
of its value as manure. Indeed, since the refuse of a product is 
often in this respect more valuable than the extract, it might 
almost as well be asserted that the cheaper article had the higher 
manurial value ; the relation of wheat-flour to bran and of oil to 
oilcakes being cases in point, of which the former is material to 
the question before us ; since if the value of man's excreta were 
calculated on the supposed number of bushels of wheat required 
for the supply of the population, the sum arrived at would be 
too high, because that part of the wheat which has the highest 
manurial value, viz. the bran, would practically not be consumed 
by him. If, again, we look to meat, the other important ele- 
ment of his diet, it at once appears how little the price of food 
has to do with its manurial value. 
In reply to an inquiry. Dr. Voelcker has obligingly furnished 
me with the following information as to the probable manurial 
value of a ton of cooked meat which has served as food for man : — 
" Cooked meat contains, in round numbers, — » 
Fibriu 18 per cent. 
Fat and mineral matter 4 ,, 
Water 78 „ 
" Fibrin contains 16 per cent, of nitrogen ; and consequently 
1 ton of meat yields in round numbers about 30 lbs. of ammonia, 
worth 15.S'. If the meat is all consumed by full-grown men, and 
consumed with starchy food, most of the nitrogen is again found 
in the excreta. Supposing about J ton to pass off in the exhala- 
tions (I am afraid to give you positive data, for the determina- 
tions of dlfTerent experiments vary considerablv), then the ton of 
meat made into manure would be worth about 12s. ' 
