The Conservation of Farm-yarcl Manure. 
839 
not altogether be very heavy, and would be partly, if not altogether, 
counterbalanced by the increasing consumption of peat-moss litter. 
Altogether, as a rough estimate in round figures, we should probably 
be fairly justified in assuming that we made at least 10,000,000 
tons of straw into manure. On an average 1 ton of straw makes 
4 tons of fresh dung, so that our estimate would work out to at 
least 40,000,000 tons as the annual production of farm-yard manure 
in the United Kingdom. At M. Grandeau’s valuation — an average 
of over 8s. per ton — this would be worth 16,000,000/. sterling. 
Even at the more moderate estimate of 5s. per ton, which would 
perhaps commend itself preferably to English farmers, the value 
would be as much as 10,000,000/. sterling. Dung on an average 
would probably contain nearly 0’5 per cent, of nitrogen, and if it 
lost from one-fourth to one-fifth of this (as M. Grandeau calculates 
to be the case) from the average ill-treatment to which it is subjected 
in production and storage, the loss would amount to between 2 lb. 
and 3 lb. of nitrogen per ton, oratotal of from 35,714 tons to 53,571 
tons of nitrogen. This would be as much nitrogen as would be con- 
tained in from about 230,000 tons to 340,000 tons per annum of 
nitrate of soda, costing, at 10/. per ton, 2,300,000/. to 3,400,000/. 
sterling. This is from twice to three times the quantity of nitrate 
of soda at present used as manure in the United Kingdom. 
As the small and thrifty French farmer is scarcely likely to be 
less careful of his manure than the average English farmer, there 
appears to be no reason to regard this estimate as an excessive one. 
On the advantages of deep feeding-boxes and covered yards it is 
unnecessary to add to what has been already said. Those who 
possess them are possessed of distinct advantages over and above 
such as relate to the conservation of their farm-yard manure. But 
even those who have not may diminish their losses by the means 
already indicated. 
It should perhaps be pointed out that the “ phosphatic gypsum ” 
used for preservation in the experiments of Holdefleiss, although an 
article to be readily and cheaply obtained abroad, is not largely pro- 
duced in this country. The. present writer only knows of one factory 
from which it can be procured in England. In this country, there- 
fore, its place would naturally be taken by the alternative material, 
viz. ordinary mineral superphosphate, which can be obtained now at 
a very low price through any manure merchant. M. Holdefleiss 
recommends, as already stated, 1 lb. to lj- lb. of cheap superphos- 
phate per day per head of stock, sprinkled on the litter. As the 
superphosphate ordinarily sold in England is probably richer than 
that referred to, it would perhaps be desirable to mix with it some 
ordinary gypsum, costing about Is. per cwt. A mixture might be 
made of, say, 1 cwt. of ordinary superphosphate and 1 cwt. of 
gypsum, and 1^ to 2 lb. used per day for the litter of each animal. 
Thus, in a feeding-box containing ten beasts, 15 lb. to 20 lb. of the 
mixture would be used in a day. If gypsum could not be readily 
and cheaply obtained, an equal quantity of sifted earth might be 
mixed with the superphosphate. 
