1 !'-'"! SOILS — FERTILIZERS. 127 



Potash ami hroinin in Texas lakes (Amer. Fert., 52 {1920), No. 8, pp. 12, 



IS). — It is stated that hiiiies that contain pot.nsh and bromin have been dis- 

 covered in alkali lakes in (Jaines, Lynn, land Terry Counties, Tex. These lakes 

 riin;,'e in area from about ;>;") to 7,()00 acres. The sands that form the bottoms 

 of the lakes are impre^niated to a depth of from 5 to 20 ft. or more with brhie 

 that is composed essentitilly of the chlorids of sodium, magnesium, and potas- 

 .sium. 



Analyses of samples showed potassium contents of 3.9G and 4.0S per cent. 

 Analyses made by the U. S. Geological Survey showed potassium chlorid con- 

 tents of 7.51 and 7.78 per cent from the same lakes. 



IMiosphatic slags, .T. Vandormael (Jour. Soc. Natl. Agr. Belg., 2 (1920), No. 

 9, pp. 92, 9.3). — x\.nalyses of different phosphatic slags are reported and briefly 

 Ilscussed, to show tliat, asule from the basic calcium phosjihate, phosphati<- slags 

 contain not only elements such as phosi)horus, calcium, and silicon, which are 

 norninlly necessary in the construction of plant tissues, but also diastatic ele- 

 ments such as nuinganese and sulphur in soluble form. 



A new metliod for rendering insoluble i)hosphates available, T. E. Keitt 

 and A. W. IMukkay {Georgia i<ta. Bui. 132 {1919), pp. 51-58). — Experiments are 

 reiwrted which were undertaken to determine the influence of composting com- 

 mercial organic ammoniates, ground rock phosphate, and rich soil on the avail- 

 ability of the phosi)horus content of the ground rock phosphate, and on the loss 

 of ammonia front the organic ammoniate 4ue to composting. Seven compost 

 lieaps were made, using cottonseed meal as the source of ammonia and Florida 

 pebl)le phosphate as the source of phosphate. 



The results include that any attempt at covering the heaps is valueless as far 

 as the amount of available phosphate is concerned. The highest percentage 

 was obtained where there was no attempt to control the temperature. The 

 Florida pebble showed a higher availability in the laboratory test than the Flor- 

 ida soft phosphate. However, at the end of four weeks composting the Florida 

 .soft phosphate showeil the higher availability. There was a consideral)le loss 

 <*f nitrogen from each of the heaps. This, and the fact that there was gen- 

 erally some loss ()f phosphoric acid, is taken to indicate that some loss may have 

 been due to leaching when the heaps were wetted. 



It is concluded that a part of the phosphoric acid content of raw rock phos- 

 phate can be made available by composting with cottonseed meal, some being 

 converted to a water-soluble form. There was a markeil increase over the 

 first determinations of water-solul)le phosphoric acid, which can be accoimted 

 lor i»y the water-soluble content of the cottonseed meal. 



The liberation of native soil ])otassiuni induced by different calcic and 

 mngncsic materials, as measured by lysimeter leachings, W. II. IMacIxtire 

 (.S'o(7, ^ci.,'8 {1919), No. 5, pp. 337-395, figs. 21).— Thia paper, a contribution 

 from the Tennessee Experiment Station, reports lysimeter experiments witli 

 Cumberland loam and Cherokee sandy loam soils. The Cumberland loam ex- 

 r>eriments included 46 tanks with and without subsoil receiving varying amounts 

 of nine dilTerent forms of lime and magnesia, and data were secured on the 

 total potassium leached during each of five years. Twenty-two tanks were 

 used with the Cherokee sandy loam to study the effect of single light applica- 

 tions of burnt lime, burnt magnesia, limestone, and dolomite upon the oiUgo 

 of potassium. Observations were also made on the potassium-liberating tend- 

 encies of calcium and magnesium sulphate derived from ferrous sulphate, iren 

 pyrites, or sulphur when these three materials were used alone and together 

 with light and heavy applications of lime or magnesia. 



"The results from thi<se two residual soils demonstrate that tlie oi'iginal 

 free soil-water leachings ari> richer in jiotassium salts than they are when 



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