1917] SOILS — FERTILIZERS. 325 



feeding." It is further concluded tliat organic matter is not lost so rapidly and 

 more accumulates in the soil when it is incorporated in the soil than when ap- 

 plied to the surface. 



The utilization of the nitrogen of manure in relation to the time of manur- 

 ing' the soil, A. Sabashnikov {Selsk. Khos. i Liesov., 249 {1915), Dec, pp. 

 499-512). — ^The general question of the utilization of manure nitrogen by crops 

 is discussed, and 11 years of experiments with rye and 4 years of experiments 

 with wheat are reported which showed that larger increases in the rye crop were 

 obtained when manure was plowed under in June than when plowed under in 

 May. The opposite was the case with wheat. A decrease in the rye crop and 

 the smallest increases in the wheat crop resulted from plowing under manure 

 in April. It was further found that in years in which the summer and autumn 

 were rainy and the rye grew thickly and was beaten down the following spring 

 by wind or rain, manure lowered the yields. 



Bat guanos, P. L. Gile and J. O. Cakrero (Porto Rico Sta. Rpt. 1915, pp. 13, 

 14)- — On the basis of the results of analyses of 200 samples of bat guanos for 

 nitrogen and phosphoric acid and experiments on the availability of the phos- 

 phoric acid of the guanos as compared with acid phosphate, bone meal, and 

 basic slag it is stated that " the greater part of the guanos are to be considered 

 as low-grade phosphatic fertilizers." The total phosphoric acid is very variable, 

 ranging in the samples analyzed from 1 to 42 per cent. 



" By vegetation tests it appears that if the availability of the phosphoric acid 

 in acid phosphate is taken as 100 per cent, the effectiveness of the phosphoric 

 acid in different guanos ranges from zero to 100 per cent. With most guanos 

 the solubility of the phosphoric acid in neutral ammonium citrate parallels 

 very closely its availability as determined by vegetation tests with corn and 

 millet. As phosphatic fertilizers the guanos are equally effective for corn and 

 mUlet. Most of the deposits contain but little nitrogen, although there is a 

 small amount of material in nearly every cave, generally the first 2 to 3 in. of 

 the deposits, that contains considerable nitrogen. The very fresh material 

 that has undergone no decomposition may contain 10 to 11 per cent of nitrogen." 



The availability of nitrogen in garbage tankage, J. P. Schboeder {Amer. 

 Pert., 45 (1916), No. S, pp. 21-23).— The results of pot culture tests on the avail- 

 ability of the nitrogen of garbage tankage are briefly compared with those ob- 

 tained by the alkaline permanganate method. The conclusion is drawn " that 

 a higher availability should be accorded the nitrogen in garbage tankage than 

 that indicated by the permanganate methods." 



Potash in Salduro salt deposit, H. S. Gale (Engin. and Min. Jour., 102 

 (1916), No. 18, pp. 780-782).— A brief description of the Salduro salt deposit on 

 the western border of Utah is given, together with analyses of the salts and the 

 brine from the Salduro salt marsh. The deposit covers an area of over 100 

 square miles and varies in thickness from 3 to 5 ft. The brine analyses show 

 a potassium content of from 2.85 to 4 per cent of the dissolved salts or from 0.76 

 to 1.03 per cent of the original solution, which is said to be about half the potas- 

 sium content of the Searles Lake brine and twice that of the Great Salt Lake 

 water. 



Action of calcium carbonate on acid phosphate, E. W. Mageudeb (Amer. 

 Fert., 45 (1916). No. 8, pp. 30-32). — Further experiments, similar to those re- 

 ported by Brackett and Freeman (E. S. R., 34, p. 26) on the effect of mixing 

 calcium carbonate in the shape of ground oyster shells with acid phosphate a 

 month old and acid phosphate only a few days old, are reported. 



It was found that new acid phosphate was acted on more readily by the 

 oyster sliells than the older acid phosphate, the reaction beginning at once and 



