1919] SOILS — FERTILIZERS. 323 



sodium nitrate, tended to remain neutral or become alkaline, but where no 

 sodium nitrate or only a small proportion was in the mixture the soil became 

 acid. The lime requirement increased as the proportion of sodium nitrate in 

 the fertilizer mixture used decreased. 



Nitrate in Amargosa Valley, southeastern California (Amer. Pert., Jf9 

 (1918), No. Jf, p. 32). — Investigations by the U. S. Geological Survey on the 

 nitrate deposits in the Amargosa Valley in southeastern California have led 

 to the following conclusions: 



" The nitrate in the Amargosa district occurs in a blanket of so-called 

 * caliche' about 5 in. in average thickness, which lies about 9 in, below the 

 surface of the ground. The nitrate is accompanied by other salts, chifley 

 sodium chlorid. The soil above and the bedrock below the deposits contain 

 insignificant amounts of nitrate. The high dip and the great thickness of the 

 strata covered by the prospecting make it improbable that deeper beds of 

 nitrate occur in this region. The caliche in general contains an average of 

 less than 2.5 per cent of sodium nitrate, the areal distribution of which is 

 uneven. 



" The Zabriskie field, in which the newly found deposit was reported to lie, 

 contains no commercially valuable nitrate. The Upper Canyon and Lower 

 Canyon fields, the most promising in the Amargosa district, together contain, 

 according to careful estimates, about 168 acres of niter-bearing deposits, which, 

 if worked regardless of cost, might produce about 1,980 short tons of refined 

 nitrate. 



" The quantity of nitrate available in the Amargosa district is so small and 

 the cost of production would be so great that the district as a whole can not 

 be regarded as a source of commercial nitrate. No further work on the areas 

 already examined is justified, except, perhaps, as purely scientific research. 

 The occurrence of caliche nitrate deposits in the Amargosa district, rather 

 than the usual cave or disseminated deposits, makes it seem possible, though 

 improbable, that really valuable deposits of nitrate may occur elsewhere in 

 the same general region. Prospecting should be continued until all similar de- 

 posits in other districts have been tested sufficiently to determine their value." 



IsTitrogenous fertilizers: Their use in India, C. M. Hutchinson (Agr. Jour. 

 India, 14 {1919), No. 2, pp. 203-214)^ — From this discussion, it is concluded that 

 nitrogen is required in Indian agriculture, but that other plant-food con- 

 stituents are also needed, without which, in most cases, nitrogen would do 

 more harm than good. It is stated, further, that India can not afford to 

 import nitrogenous fertilizers at the same rate as other countries having 

 greater mineral wealth and local consumption, but must depend rather upon 

 a better utilization of indigenous supplies of nitrogen and upon more intensive 

 methods of farming designed to maintain the fertihty of the soil. 



Some information and suggestions concerning the use of phosphorus, 

 M. M. McCooL, G. M. Grantham, and C. E. Millar (Michigan Sta. Bui. 284 

 {1919), pp. SO, figs. 22). — This comprises a general discussion of the terms used 

 in connection with phosphate fertilizers ; commercial phosphorus carriers ; 

 the effect of phosphate fertilization on crop growth and on the soil ; the time, 

 manner, and amount of the phosphorus application ; the removal of phosphorus 

 from different types of JNIichigan farms and the amount of commercial phos- 

 phate required to make good the loss ; the amount of phosphorus in the surface 

 layer of some typical Michigan soils ; and results secured from the use of 

 phosphate fertilizers on Michigan farms. 



Florida's soft rock phosphate (Com. Pert., 18 (1919), No. 5, pp. 36, 38).— Ex- 

 periments of one year's duration, conducted at the North Carolina Experiment 

 Station, in which soft rock phosphate was compared with 16 per cent acid 



