526 



Agricultural Chemistry — Turnips, 



decomposed bone-earth would have given much the largest 

 amount of bulb as well as entire plant. 



Sulphuric acid, as the decomposing agent, indicates in every 

 case a considerably more rapid determination to bulb than either 

 the undecomposed earth or that acted upon by the hydrochloric 

 acid ; and, excepting where ammoniacal salt is superadded, there 

 is a perceptible progression as the amount of acid is increased. 

 Where the ammoniacal salt was used, though the formation of 

 hull) is not greater under an increase of acid, there was here, as in 

 the case of the hydrochloric acid, a larger development of leaf. 



The eff'ect of an equal amount of superphosphate of lime on 

 land ploughed in the ordinary way, or which had been dug 9 or 

 18 inches deep in the previous year, is here shown : — 



Plot 

 Nos. 



Land, how Tilled. 



Average weight of Bulbs. 



Drilled 

 Manures 

 only. 



Drilled 

 Manures, 



and 10 cwt. 



Rape-cake 

 per Acre, 



Drilled 

 Manures, 



and 3 cwt. 



Snlph.Am. 

 per Acre. 



Drilled 

 Manures, 

 and 3 cwt, 

 S.ilph.Am 

 and 10 cwt 

 Eape-cake 

 per Acre. 



12 

 -14 



22 



Land dug 9 inches in 1844 (11 cwt. ) 



superphosphate of lime) . . , ) 

 Land dug 18 inches in 1844 (11 cvvt, 1 



superphosphate of lime) . . . j 

 Land only ploughed (11 cwt. super-l 



1-20 

 ]-30 

 1-17 



1-39 

 1-33 

 1-33 



M9 

 1-30 

 1-06 



1-07 

 M9 

 1'17 



Excepting in column 2, the rapidity of bulb-formation is 

 slightly the greatest where the land is deeply trenched, and in 

 the exceptional case a larger development of leaf was found. The 

 land dug 9 inches deep also shows a slight superiority over that 

 which was only ploughed. The differences are not quoted as 

 offering any adequate advantage for so expensive a process as 

 spade-digging; but the facts themselves help to indicate the 

 character of the conditions required in turnip culture. 



We shall next show the result of the yearly supply of alkalis, 

 compared with that from a plot (No. 21) which had been 

 drained of them by a course of ordinary cropping, succeeded by 

 the removal of two crops of turnips : — 



In the first two columns, where, as we shall presently show, the 

 balance of organic constituents was more favourable to bulb-form-d- 

 tion than in the other cases, we find a greater development of 

 bulb in an equal period of time by superphosphate of lime alone, 

 than when the alkalis, either separately or united, were supplied 

 with it. It is remarkable, too, that in No. 17, where j^o^a^s was 

 employed, there is a general inferiority observable. Again, of 



