Agricultural Chemistry — Turnips, 



555 



contrary to otherwise probable indications; we find however, that, 

 slight as the differences are, they are such in kind as other cir- 

 cumstances would lead us to anticipate; and we need only notice 

 that the percentage of ash is seen to be highest where the nitro- 

 genous condition of manuring w^as predominant, and lowest where 

 the carbonaceous was more characteristic. 



The variations are, however, more apparent when the per cent- 

 ages of ash upon the dry, rather than upon the fresh, matter are 

 are given. The mean percentage of the dry matter itself, and 

 of its ash, in the specimens last quoted, and of the nitrogen in 

 the dry matter of two of the specimens in each case, are here 

 tabulated : — 





Percentage 



Percentage 



P^-rcentage 





of Nitrugi-n 





of Dry 



of Asli 



in Dry 



General Descrijition of Manuring. 





Matter 



Matter in 



in Dry 



(Specimens 

 Nos. 9 and 





Bulb. 



Matter. 



22). 



1845. Mean of 13 experiments by purely mineral) 



8-34 



6-99 



1-52 







1845. Mean of 13 experiments by mineral manures) 

 1845. Mean of 13 experiments by mineral manures! 



7-97 



7-21 



1-91 



7*41 



8-24 



2-86 



1845. Mean of 13 experiments by mineral manures) 

 and ammoniacal salt and rape- cake « . J 



7-48 



8-08 



2-33 



The coincidences here brought to view are of considerable 

 interest, and clearly show a constant decrease in amount of mineral 

 matter as the deposition of solid vegetable substance progresses. 

 We have with the highest proportion of dry, the lowest proportion 

 of mineral matter ; and wdth the lowest amount of dry matter, the 

 highest of mineral substances ; and even with the slight increase 

 in dry matter exhibited in line 4, compared with line 3, we have 

 a decrease in the percentage of mineral constituents. We can 

 scarcely fail to recognise in these results a marked distinction 

 between those constituents of the bulb w^hich are as yet merely 

 circulatory and unappropriated, and those which are secreted and 

 fixed, the former being indicated by a small amount of dry matter 

 and large amount of ash, and the latter by a large amount of dry 

 matter and a small amount of ash. 



The connexion between the amount of dry matter and its per- 

 centage of ash being admitted, and that between the amount of 

 nitrogen, that of dry matter, and the condition of maturation 

 having been pointed out before, it is seen that the views taken 

 are fully confirmed by the relation of the ash in the dry matter to 

 that of the nitrogen in the same. Thus we have in the Table, 

 v/ith the most iixed matter and least nitrogen, also the least ash ; 



