see Appendix, Note VIII., p. 283.

[150] According to Storer, in a ton of autumn leaves of the best quality
there would be 6 lb. of potash, less than 3 lb. of phosphoric acid, and
10 or 15 lb. of nitrogen. Another substance that may be used as a litter
is sawdust. This substance is a good absorbent, but is of little value
as a manurial substance.

[151] Heiden's 'Duengerlehre,' vol. ii. pp. 34, 66. In Boussingault's
experiments the food consisted of 15 lb. _hay_, 4.54 lb. _oats_, and 32
lb. water; the total excrements amounting to 31.16 lb., containing 7.42
lb. dry matter. In Hofmeister's experiments the food consisted of 5.23
lb. _hay_, 6.18 lb. _oats_, 1 lb. _chopped straw_, and 25.57 lb. water;
the excrements amounting to 25.07 lb., containing 5.32 lb. dry matter.

[152] This is taking no account of the amount of water which the manure
will absorb, and which will probably double the quantity.

[153] See Appendix, Note IX., p. 283.

[154] The rapid fermentation of horse-manure is due to its mechanical as
well as its chemical nature. The horse does not reduce its food to such
small pieces, and its urine is rich in nitrogen.

[155] Schulze recommends one-third of a pound per day of sulphate of
lime for each horse.

[156] See Appendix, Note X., p. 284.

[157] The food consisted of 30 lb. _potatoes_, 15 lb. _hay_, and 120 lb.
_water_.

[158] For further analyses of cow-manure, see Appendix, Note XI., p.
286.

[159] This is for a pig of six to eight months old, and fed on potatoes.

[160] It has been asserted that the use of pig-manure, when applied
alone, is apt to give an unpleasant taste to the produce grown.

[161] Taken from a very large number of analyses by a number of
experimenters. See Heiden's 'Duengerlehre,' vol. i. p. 99.

[162] See Storer, 'Agricultural Chemistry,' vol. ii. p. 96.

A question of great importance is as to the amount of farmyard manure
produced on a farm in a year, and its value. This is a question which is
extremely difficult to satisfactorily deal with. Various methods of
calculating this amount have been resorted to. It may be well to state
these pretty fully. Some practical authorities estimate the amount by
calculating that every ton of straw should produce 4 tons of manure.
Another method consists in estimating the amount from the size of the
farm. Sir John Lawes has calculated the composition of farmyard manure
which should be produced in the case of a farm of 400 acres, f