522 



Agricultural Chemistry — Turnips. 



With such a mass of experimental evidence before us, it is 

 difficult to select a starting-point such as will lead us to the most 

 natural order of illustration, and the clearest comprehension of 

 their most prominent indications and conclusions. In many 

 respects these results are most interesting, confirming as they do 

 the opinions suggested by those which have preceded them ; and 

 affording at the same time data, the consideration of which enables 

 us to determine other important questions than those already 

 attended to. 



It will be recollected that the statement given of the character 

 of this third season, compared with that of the second, was, so far 

 as all the conditions shown to be essential to the vigorous growth 

 of the turnips were concerned, very much in favour of the one 

 about to occupy our attention ; and it is seen that the acreage 

 produce is pretty uniformly nearly doubled where artificial supply 

 for organic formations is much the same. It is true that the 

 number of plants per acre being much greater than heretofore, 

 some of the actual acreage increase may be attributed to this 

 cause ; but all we wish to maintain is the general effect of season 

 upon the growth of the cultivated turnip. 



The absolute necessity of a liberal supply of constituents, even 

 with the most favourable climatic circumstances, and under the 

 influence of the best observed conditions of self-reliance, or col- 

 lective power depending on mineral supply, is, however, clearly 

 proved by the results of the farm-yard dung, the unmanured 

 plot, and the mean of the purely mineral manures. They are 

 here given in illustration. 



Selected Results. 



Description of Manures. 



Bulb per Acre, in 



Average 

 weight of 

 Bulbs in 

 lbs. and 

 tenths. 



Number 

 of 

 Plants 

 per Acre. 





Tons. cwts. qrs, lbs. 

 0 13 2 24 



0-11 



13,296 



Mean by purely mineral supply 



12 8 2 3 



1-16 



23,882 





17 0 3 6 



1-61 



23,731 



Thus, in the best suited of the three seasons to which our ex- 

 periments refer, the unmanured plot gives a produce of only 13 

 cwts. per acre, an average weight of bulb under 2 ounces, and a 

 number of surviving plants little more than half that observed 

 under conditions of artificial supply. In this same season, on the 

 other hand, the farm-yard dung gives the largest acreage produce 

 obtained throughout the entire series of seasons and experiments, 

 a weight of bulb higher than any other manure in the same 



