Oil the Ptitrefaction of Bones. 
531 
in a free pulverized state, should be moistened, and the Ijones 
thoroughly drenched. Finely-ground bones decay more than 
coarsely-ground. In order to ascertain every possible cause of 
failure, I procured some boiled bones, and making them up in a 
heap at the same time with unboiled bones, found that the former 
have not heated so well nor fallen to pieces nearly so much as the 
raw bones. Stale bones from a kennel, roughly pounded, would 
not heat, I am told, at all. Bulk of the heap is a decided 
advantage. Four cartloads in one heap heated much better, I 
found, than four cartloads in separate heaps. As the heat does 
not maintain itself well within a foot of the surface, it is useful to 
give the heap an external covering of the same material employed 
in the mixture. On the other hand, the quantity of ashes or sand 
employed may be reduced, I believe, to one-half of the quantity 
of bones. A bone-merchant has told me that, having made uj) a 
large heap, he turned it and watered it afresh at the end of a fort- 
night, and that at the close of a month very few whole bones 
remained. I may add the result of two trials made here this 
summer with late-sown turnips : — 
Cost. Yield. 
£. s. d. Tons. Cwt. 
5 J bushels of superphosphate per acre . 1 17 0 16 12| 
8 „ decayed bones ... 1 2 0 13 14 
No manure. Much less than . . — 10 
These bones were from a small heap and not well decomposed. 
On two other lots, where the bones employed had lain in a large 
heap, and been better fermented, the yield was just even : — 
Cost. Yield. 
£. s. (!. Tons. Cwt. ILs. 
5 J bushels of superphosphate . 117 0 15 13 67 
8 „ bones .... 1 2 0 15 12 0 
The superphosphate always pushes on the turnips faster at 
first, and therefore is best for late-sown turnips. For those that 
are sown early, though I do not think that this mode of decom- 
position will supersede the use of acid, I cannot but hope that it 
may afford the farmer, in some circumstances, a useful choice. I 
should mention that salt has been thought to check the process, 
which is not surprising, as it is an anti-putrescent. As to the 
time during which the bones should lie in the heap, I do not 
feel sure whether or not the process of heating should be allowed 
to expend itself. I need scarcely add, what seems generally 
known, that before drilling this or other manures the compound 
should be mixed with ashes or some other medium which will 
drill readily, in order to diffuse it in the soil and give each rootlet 
of the young plant a chance of finding it. 
Pusey, Dec. 2, 1848. 
