SOILS FERTTLIZEES. 217 



Examinations of canal water nsed for irrigation of whoat, rice, and sugar cane 

 showed tliat during tlie tiood season tlie silt in the amount of water used on rice 

 would carry as high as 32 lbs. of nitrogen and 42 ll)s. of phosphoric acid. The 

 amount used on the wheat crop, however, would probably fvu-nish not more 

 than 5 lbs. each of nitrogen and phosphoric acid. 



The process of i)ercolation employed in Indian saltpeter works to obtain a 

 strong, almost saturated, solution of salts is briefly described, and a study of the 

 composition of " sitta," a product obtained in the process of refining the saltiK'ter, 

 is re])orted. The product is mainly sodium chlorid, but often contains adnux- 

 tures of from 2 to 14 i)er cent of saltpeter, which mainly determines its agri- 

 cultural value. 



Plan for a soil test with fertilizers, W. Freak {PcnusjiU-unia Sta. Rpi. 

 190.5, pp. 22-1'), ]il. /). — A plan of an experiment to determine the most profitable 

 kinds of fertilizing materials to a])ply to corn or wheat is descrilunl. 



Cooperative fertilizer trials in Sweden, 1905, P. Bolin {K. Laiidthr. Ahad. 

 Handl. och Tidskr., 1906, Bihanij, pp. 121). — The fertilizer trials discussed in 

 this report were conducted in 14 different counties by county agricultural so- 

 cieties in cooperation with the Royal Agricultural Academy. Two hundred and 

 fifty-four different trials, including about 7,000 plats in the aggregate, were con- 

 ducted, viz, 130 trials with spring grains, SS with root crops, 35 with pastures 

 or meadows, and 1 with winter grains. The general plan of the trials was 

 similar to that of earlier years (see E. S. R., 15, p. 5G9 ; 17, p. 654). The 

 n>i>ort contains complete details as to the conditions under which the individual 

 trials were conducted, the system of fertilization adopted, and the results ob- 

 tained, with genei'al discussions of the latter. 



Among special trials conducted during the year the following may bo noted : 



Comparative trials icith ammonium sulphate and nitrate of soda. — These 

 trials were conducted with potatoes (0 trials), mangels (5 trials), fodder beets 

 (3 trials), and oats (8 trials). The fertilizers were applied at the rate of 

 either 35 or 25 lbs. of nitrogen per acre for the crops mentioned, except for oats, 

 which received nitrogen at the rates of 25 and 12.5 lbs. per acre. In the case of 

 the former crops, 35(5 lbs. of superphosphate and 178 lbs. of potash salt per acre 

 wer(» applied, in addition to the nitrogen fertilizer, and for oats, 2()7 lbs. of 

 superphosphate and 89 lbs. of potash salt. If the increase in yields produced 

 by the nitrate of soda over that on the control plats be taken as 100, the effect 

 of the ammonium sulphate was, on the average, as follows for the various 

 crops : Heavy nitrogenous fertilization — potatoes 63, mangels 78, fodder beets 

 71, and oats, grain 97, straw, 78; light nitrogenous fertilization — potatoes 54, 

 mangels (50, fodder beets 77, and oats, grain 78, straw 03. The effect of the 

 annnonium sulphate in this year's trials, on the average for all trials and all 

 crops, was cipial to 72 per cent of that of a corresponding amoinit of nitrate of 

 soda. 



Comparative trials with cyanamid, lime niter, a>nnionium sulphate, and 

 nitrate of soda. — The first fertilizer contained about 20 per cent of nitrogen. 

 and the second one (P.irkeland and Eyde process) about 11 per cent. Only one 

 of the series of trials planned was carried through successfully, viz. with oats 

 on clay soil. The results obtained showed that for this crop and soil the fer- 

 tilizer value of the lime niter was fully equal to that of the nitrate of soda, 

 calculated on the same quantities of nitrogen, and that tlu- action ot the 

 cyanamid is quite similar to that of ammonium sulphate. 



On the best time of liming fallow ground. — A field of clay soil seeded to rye 

 on August 16, 1904, was divided into plats, some of which were manured and 

 limed, while others were either manured or limed only. The manure was 

 applied June 14, and the slaked lime (3,000 kg. per hectare) either on the same 



