FEETILIZERS. 529 



diy lime (•ontaining' only traces of niag-nesia. Hungarian grass was 

 the plant grown. From the data for crop increase and nitrogen in the 

 crop the following conclusions are drawn: 



"(1 ) All application equal to 1,800 lbs. of slaked lime per acre decreased the yield 

 of grain liy 11 per cent, of straw (including roots and stubble) by 19 per cent, and 

 of crop nitrogen by about 14 per cent. 



"(2) An application equal to 3,600 lbs. of slaked lime per acre, instead of further 

 decreasing the yield, increased the yield of grain by 13 per cent and of crop nitrogen 

 by 10 percent, while the yield of straw and stubble was 14 per cent less than where 

 no lime was applied. 



"(3) Applications equal to 5,400 and 7,200 lbs. of slaked lime per acre increased 

 the croi) as follows: 



Percentage increase over crops from soil to which 'no lime was added. 



.5, 400 lbs. 

 of lime 

 per acre. 



7, 200 lbs. 

 of lime 

 per acre. 



Increase of grain 



Increase of straw 



Increase of crop nitrogen. 



Per cent. 

 36.8 

 1.2 

 38.1 



Per cent. 



43.7 



1.9 



54.1 



"In these cultures, therefore, in which hard raw bone was used as a fertilizer, 

 ap]>lications of large quantities of slaked lime (two and three times as much lime as 

 l)one) increased the grain in the crop by 36 to 44 per cent and the crop nitrogen by 

 38 to 54 i)er cent over the yield from pots to which no slaked lime was added; but 

 the yield of straw was not increased by the use of lime. From this series alone can 

 not be calculated the actual percentages of the fertilizer nitrogen recovered in the 

 crop, for the yield of crop nitrogen from the soil without fertilizer is not determined 

 nor the effect of the lime in making the soil nitrogen available. Further experi- 

 ments are being made on these points. These cultures, however, prove that slaked 

 lime has made very much more available the nitrogen of the soil, or more probably, 

 the nitrogen of the bone which without lime was almost inert as a fertilizer." 



The comparative value of nitrate of sodium and sulphate of 

 ammonium as manures, R. Warington {Jour. Roy. A(jr. Soc. Kng- 

 land, J. .s-(/'., 11 {1000), jtt. 2, No. ^'2, pp. J00-S46).—A general discus- 

 sion of this subject based largely upon the results of experiments at 

 Rothamsted and Woburn. It is shown that ammonium sulphate is 

 slower in action than sodium nitrate because it must first undergo 

 nitrification. When the conditions are unfavorable to nitrification, 

 that is, when the soil is deficient in lime and the season is dry, sodium 

 nitrate, being soluble and immediately av^ailable as plant food, gives 

 better results than ammonimn sulphate. In a wet summer, however, 

 and on a soil abundantly supplied with lime, ammonium sulphate fre- 

 quently gives better results than sodium nitrate. ' ' This influence of cli- 

 mate is most clearly seen in the case of cereal crops, or on grass lands; 

 it is less perceived in the case of crops like potatoes and mangels, which 

 have a longer period of growth.'' It is stated that the slower action of 

 ammonium sulphate as compared with sodium nitrate is not entirely 



