SOILS — FERTILIZERS. 631 



mated that 190 lbs. of potassium chlorid per tou of feldspai- could be obtained 

 by this process. 



" The residue left after the potash has been removed, by aqueous extraction 

 or otherwise, contains all the essential elements of a cement into which it 

 could be transformed by ignition, supplementing the deficiency of calcium oxid 

 with limestone, if required. No previous grinding would be necessary in this 

 instance, since with the temperature kept reasonably low the mass does not 

 clinker and disintegrate easily in water. Moreover, both the silica and the 

 alumina of the original feldspar have been rendei'ed extremely reactive and 

 should therefore readily form cement on the subsequent operation." 



Potash in China {Chem. Trade Jour., 49 {1911), No. 1259, p. 20).— Brief 

 extracts from reports of British consuls in China are given, showing that there 

 is no evidence of the occurrence of natural deposits of potash in that country. 



The use of fine ground raw phosphate as a substitute for Thomas slag', 

 T. Remy (Lamlw. Jahrb., JfO (1911), No. 3--'i, pp. 5-5.0-677).— Comparative tests 

 of Thomas slag and Algerian, Lahn, and Florida phosphates in field and pot 

 experiments with grasses, grains, peas, lupines, and mustard are reported. 



Except in a few cases with winter grain and lupines the raw phosphate 

 was inferior as a fertilizer to Thomas slag. Thomas slag was from 63.8 

 to 76.6 per cent as effective as superphosphate, and Algerian phosphate 

 from 5.5 to 12.8 per cent as effective. The results with Florida and Lahn 

 phosphates were not materially different from those with the Algerian phos- 

 phate. The use of the insoluble phosphates in connection with decaying organic 

 matter or sodium bisulphate greatly increased their efficiency. 



Analysis of phosphates as a guide to their conversion into superphos- 

 phates, P. Hardy and J. Vandormael {Bui. Soc. Chim. Bclg., 25 {1911), No. 



1, pp. fi3-57 ; (lbs. in Bid, Imp. Inst. [80. Kensington}, 9 {1911), No. 1, pp. 52, 

 53; Chem. Trade Jour., J,8 {1911), No. 1255, p. 613).— The authors show as a re- 

 sult of an elaborate study of 3 natural phosphates and of superphosphates 

 made from them " that for industrial purposes the quantity of sulphuric acid 

 necessary to convert a given quantity of natural phosphate into superphosphate 

 may be calculated if the following constituents of the natural phosphate are 

 known, viz, total lime, phosphoric acid, sulphuric acid, ferric oxid, and alumina, 

 and in making analyses of phosphates from new sources it is sufficient for ana- 

 lysts to determine these constituents." 



The pyrophosphates, new phosphatic fertilizers in th.e cultivation of 

 sugar beets, E. Voglino {Coltivatorc, 56 {1910), No. 30, pp. 370-372; abs. in 

 Internat. Inst. Agr. [i?ome], Bu}. Bur. Agr. Intel, and Plant Diseases, 1910, No. 



2, p. 233). — Experiments with 2 commercial products, one simple pyrophos- 

 phate, the other acid pyrophosphate, containing 17 and 19 per cent, respectively, 

 of phosphoric acid soluble in dilute citric acid, are reported, the results showing 

 that the first was inferior, the second superior, to suijerphosphate as regards 

 effect upon the yield of beets. There was, however, no difference in the sugar 

 content in the two cases. 



Calcium requirements of plants and the different relations of the cal- 

 cium and magnesium in nutritive solutions, N. I. Konovalov {Land 10. Vers. 

 Stat., 74 {1911), No. 3-5, pp. 3.'t3-360; abs. in Jour. Chem. Soc. [London], 100 

 {1911), No. 581, II, p. 222). — Pi'eviously noted from another .source (E. S. R., 

 25, p. 127). 



[The lime-magnesia ratio and chlorosis of citrus fruits], C. B, Lipman 

 and R. R. Snowden {Pacific Rural Press, 81 {1911), Nos. 21, pp. Jfl2, 413; 24, 

 pp. 4'^2, 47s ). — These articles attack and defend certain conclusions drawn 

 by R. R. Snowden in an article previously noted (E. S. R.. 24, p. 525) regarding 

 the relation of the lime-magnesia ratio and chlorosis of citrus fruits. 



