SUBSTANCE IS THE PHOSPHATE OF LIME. 



181 



From some recent and valuable experiments of Mr. Pusey 

 and Mr. Brooks, of Hatford,i it is probable, as we have long- 

 since elsewhere suggested, that by finely dividing bones by 

 putrefaction, and mixing them with gypsum powder, an 

 effect may be produced upon turnips similar to that of using 

 the superphosphate of lime. Mr. Pusey sajs, " I mixed 

 eight bushels of crushed bones with sixteen bushels of our 

 brick-coloured peat-ashes. In a few days, the heap began 

 to heat violently, and the heat lasted for ten days : the 

 whole was reduced to a fine reddish-grey powder. On try- 

 ing this compost by the side of superphosphate, with a crop 

 of turnips, the effect was precisely the same : the ashes cost 

 only fourpence for two bushels — the acid would have cost 

 five times as much. The superphosphate of lime appears to 

 answer very well for wheat. Mr. P. Leigh obtained the 

 following results per acre : — ^ 



It is noticeable that oil-cake, which is found so enriching 

 to the dung" of live stock, abounds with phosphate of lime. 

 In the ashes of the gold-of-pleasure cake (constituting 6'89 

 per cent, of the cake), of English linseed-cake (constituting 

 7'25 per cent.), and of American linseed-cake (constituting 

 6*35 per cent.), were found by Mr. Fromberg, — ^ 



Gold of 

 1 Pleasure. 



Alkaline salts I 30-43 



Phosphates of lime and magnesia 40-56 



Lime i 3*46 



Magnesia j 0-49 



Silica I 13*65 



Sand I 10-84 



Enslish 

 Cake. 



American 

 Cake. 



31-55 



47-67 



4-88 



1-51 



10-81 



3-86 



38-20 



56-26 



1-24 



a trace 



4-04 



' Jour. R. A. S., vol. vi. p. 327. 

 " Trans. High. Soc, 1846, p. 203. 



* Ibid. vol. V. p. 605. 



