212 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
When made from oat straw the manure will have a greater 
value than when wheat or barley straw has been employed as 
litter. Wheat straw is superior to barley straw in the amount 
Of potash and nitrogen it will yield. 
Use of Stable and Farmyard Manures. 
The physical effect of these manures upon soils is equally 
important with its chemical influence. The general rule 
according to which short or well-rotten dung is applied to light, 
open soils, and long fresh dung to heavy, compact soils, is 
intimately associated with the mutual physical relations of 
soils and manure. 
The fresher the dung the less ready are its constituents to 
enter into combinations available as plant -food ; and in this 
form a stiff clay soil is well adapted to hold or retain it till the 
occurrence of those chemical reactions which result in rendering 
the nutrient ingredients of the manure presentable to the plant. 
The older and the more rotten the dung before application, 
the more promptly are its fertilising ingredients available ; and 
as light, porous soils are deficient in retentive power, it is well 
they should receive dung in an advanced state of decomposi- 
tion, and at a time when the crop is ready, or almost ready, to 
make use of it, loss of manurial substance by means of the 
drainage waters being thus avoided. 
Long or ** green " manure helps to open up stiff tenacious 
soils, and the fresh straw provides air-channels, along which the 
atmosphere can find its way into the recesses of the soil, oxida- 
tion being thereby promoted. Conversely, the application of 
short or much decomposed dung to a light or sandy soil has 
the beneficial effect of making it firmer, and of rendering it less 
readily permeable by water. 
Bones as a Manure, 
For a long time bones have been used as a manure ; and as 
they contain so large an amount of organic matter and phosphate 
of lime, it is easy to understand why impoverished soils should 
be greatly improved by what is called " boning." 
At one time bones used to be roughly broken and applied 
in the proportion of 20 cwts. or 80 cwts. per acre ; but as it was 
observed that the bones did not readily crumble or dissolve when 
