( 3-24 ) 
XXI V^. — On Siipcri)liosj>hate of Lime. By Pii. Pusey. INI. P. 
Dr. Liebig's great discovery of dissolving bones in sulphuric 
acid for the purposes of manure, has been so clearly established 
by the experiments as well of the Duke of Richmond as of other 
farmers, and so fully investigated by Mr. Hannam, that nothing 
seems now to be wanted but some plan for bringing it within the 
ordinary routine of farming. Though the mixtures hitherto pre- 
pared have answered perfectly, they have mostly been supplied to 
the turnip-crop in the shape of liquid manure. This mode, how- 
ever, requires either tedious labour by hand, or an expensive 
watcrcart made for the purpose ; and in neither way would be 
adapted, I think, to the hurry which generally accompanies 
turnip-sowing on a large farm, where on a favourable turn of 
weather a hundred acres perhaps require to be finished while the 
soil retains the suitable temper. 
It is to the drill, therefore, I have always thought we must 
look for this object; but before stating the simple plan of mixing 
and drilling which has answered with me in practice, I Avill ven- 
ture to say a few words on the theory of Dr. Liebig's discovery. 
Bones, it is well known, have been long used in England for 
the turnip crop ; still though their success on some soils was cer- 
tain, the cause of that success was by no means so clear : for fresh 
bones are made up of oil, of jelly or gelatine, and of Phosphorus 
united with lime. But when the oil was boiled out of the bones 
they still acted, and when the jelly was burnt out of them they 
still acted even more rapidly : so that without at all saying that 
either the oil did nothing or the jelly did nothing, it became clear 
that the peculiar active principle of lioncs is the Phosphorus com- 
bined with liine ; and, as the quantity of lime is insignificant, that 
it is the Phosphorus — a pale substance like wax, which has the 
singular property of giving a faint blue light when in the dark. 
This curious substance, it appears, which may be bought for a 
few pence at any chemist s, is one of the main elements with 
which nature works in compounding seeds and roots serving (or 
the food of man and of beast. 
In bones, however, the Phosphorus, in an acid state, is com- 
pounded with lime in such a jnoportion as to form a salt called 
phosphate of lime, which water does not dissolve, and which 
therefore acts slowly upon the roots of crops to which it is applied 
as manure. Dr. Liebig knew that oil of vitriol {sulplmric acid), 
if mixed with bones, would take to itself a part of this lime, 
leaving behind a new salt containing at least a double portion of 
phosphorus, and therefore called .??/y;(?rphosphate of lime, which 
salt being readily dissolved by water, he hoped would afford a 
more digestible food for the young turnip, and the result has 
