Agricultural Chemistry — Turnips. 547 



Percentages of Nitrogen in Dry Turnip Bulbs, the produce of different 

 Manures. 



a 

 "A 

 o 



9 

 22 



Description of Diilled Manures. 



Drilled 

 Manures 

 only. 



Drilled 

 Manures, 

 and Top- 

 dressiny of 

 Rape-cake. 



Drilled 

 Manures, 

 and Top- 

 dressiiiij of 

 Amm. Salt. 



Drilled 

 Manures, 

 and Top- 

 dressing of 

 Rape-cake 



and 

 Amm. Salt. 



400 lbs. calcined bone-dust, hydro-"! 

 chloric acid = 268 lbs. sulphuric > 



11 cwt. superphosphate of lime . 



1-46 

 1-58 



1-93 

 1-89 



2-82 

 2-89 



2-22 

 2-44 







1-52 



1-91 



2-86 



2-33 



the series; that its probable extent is O'lO, and its utmost range 

 0*20. Should such general deficiency pervade our results^ it is 

 dependent partly on the fact that succulent specimens cannot be 

 fully dried in air at 212° without some loss of nitrogen^ and in 

 part also upon certain practical difficulties attending the conduct 

 of the determination of nitrogen in substances in which the actual 

 percentage is so small as in the instances before us. We may 

 add that each of the results given in this paper is the mean of 

 two determinations at least, and when there has been a difference 

 of 0*10 a third has always been made. 



Referring to the results of the table, and taking the columns 

 separately, we see a very marked coincidence between the figures 

 in each, and as marked a contrast between column and column ; 

 and if we call to mind the peculiarities of the several organic 

 conditions of manuring, we shall see the influence of the nitro- 

 genous supply to be exactly opposite to that observed in the 

 case of wheat-grain, and in fact that the per centage of nitrogen 

 in the turnip-bulb bears a direct instead of an inverse relation to 

 the predominance of that substance in the manure. 



Thus in the instances quoted the percentage of nitrogen in 

 the dry substance of the produced bulb is by mineral manures 

 alone 1*52 ; by^the addition of rape- cake, which contains, besides 

 a large amount of carbon, a considerable quantity of nitrogen, we 

 have 1-91 per cent. ; by ammoniacal salts, supplying abundance 

 of nitrogen, but no carbon, 2*86 per cent. ; and when to this ex- 

 clusive nitrogenous supply rape- cake is superadded, we have 

 2'33 per cent. There is here seen, then, very evident connexion 

 between the percentage of nitrogen in the substance of the bulb, 

 and the supply of it in the manures employed. It is worthy of 

 remark, however, that it is not the actual acreage quantity of 

 nitrogen, but its proportion to other constituents that is so clearly 

 indicated. Thus in the third column, with an acreage supply of 



