126 EXPERIMENT STATION EECORD. 



The author concludes that the standard of fine bone meal should require 

 that G5 per cent of it should pass a 50-mesh sieve, and that 90 per cent of 

 the remainder should pass a 25-mesh sieve. 



Phosphate rock, W. II. Waggaman (In The Mineral Industry: Its Statistics 

 Technology, and Trade during 1913. New York and London, 191J{, vol. 22, pp. 

 575-594). — Statistics of production and consumption of phosphate rock in the 

 United States and abroad during 1913 as compared with previous years are 

 summarized and discussed in this article. The character and possible yield 

 of the various phosphate beds are also discussed and a bibliography of the 

 subject is given. 



Potassium salts (In The Mineral Industry: Its Statistics, Technology, and 

 Trade during 1913. 'New York and London, 191Jf, vol. 22, pp. 607-621) .— Statis- 

 tics of the trade in potash salts during 1913 as compared with those of previous 

 years are summarized and. a brief account is given of the attempts to develop 

 sources of supply of potash in the United States. 



A bibliography of the subject is given. 



Potash deposits in Spain, C. B. Huest (Daily Cons, and Trade Rpts. [U. S.], 

 17 (19L't), No. 261, pp. 615-617). — It is stated that while no careful surveys 

 have been made there is evidence to warrant the belief that considerable 

 deposits of potash exist in certain provinces of Cataluna. The government 

 has granted a number of concessions covering possible deposits of potash, but 

 is undertaking to make investigations with a view to determining the extent 

 of such deposits and making reservations. 



The preparation of potash from feldspar and other sources (Chem. News, 

 110 {IDl-'t), No. 2863, p. 175). — This is a brief review of methods which seem to 

 have most promise of meeting the emergency demand for potash created by 

 the European war. Attention is called especially to a patented process based 

 upon the reduction of feldspar by fusion with fluorspar and calcium carbonate. 



Granitic soil potassium and its relation to the production of hay, B. E. 

 Curry and. T. O. Smith (New Hampshire Sta. Bui. 170 (WW, VP- 32, figs. 7).— 

 This bulletin reports a continuation of previous investigations on certain 

 gx-anitic New Hami^shire soils (E. S. R., 28, p. 30). 



These soils are, as a rule, abundantly supplied with potash. Percolation ex- 

 periments with a solution of potassium chlorid showed that in spite of this 

 fact the soils absorbed additional amounts of potash from the solution. The 

 richer the soil in clay and also in potash, the greater the absorption. The 

 absorbed potash was held so strongly that it was diflicult to recover it by 

 leaching with water. Dilute solutions of sodium nitrate, sodium chlorid, sodium 

 carbonate, and acid phosphate released considerable amounts of the soil potash, 

 the first and last named being especially active. Calcium oxid and carbonate 

 did not release potash. Calcium sulphate set free a small amount. 



A study of the results obtained in experiments in growing hay on these soils 

 indicates that nitrogen and not iwtash is the limiting factor. The supply of 

 potash is apparently suflicient even for thv^ increased growth resulting from the 

 application of nitrogenous fertilizers. The author therefore concludes that the 

 common practice of top-dressing grass land with potash fertilizers can not be 

 expected to be profitable on such soils. 



Frequent and thorough cultivation, with rotation of crops to create favorable 

 conditions for increasing the availability of the soil potash, and the use of 

 sodium nitrate, ammonium sulphate, acid, phosphate, and acidulated fertilizers 

 in general which tend to increase the solubility of the potash, are suggested as 

 preferable to applications of potash fertilizers. 



Lime in agriculture (Farmers' Ed. and Coop. Bur. [South Settlement and 

 Development Organ., Pm6.], pp. 37, pis. 2).— This pamphlet contains a series 



