SOILS — FERTILIZERS. 723 



explains the soorl results obtained from the use of slag as a fertilizer. The 

 paper also deals with the natnre of tlie mineral constituents of hones and sliows 

 that the hone phosithate is a mixture of tetracalcium and tricalcium phosphate, 

 both of whicli are in hydrated condition. 



A new deposit of phosphate of lime, A. Ciiavard (Jour. Agr. I'lut.. ii. srr., /7 

 U009), No. 25, I). 119). — An important deposit of nodular phosphate suitable for 

 the manufacture of superphosphates which has recently been discovered in the 

 Department of Aude is described and an analysis given. 



Phosphate {Ann. Rpt. Mineral I'rod. Canada, J90U [piih. 1!)09], pp. IJ,'), i//6").— 

 Statistics of production and export of apatite in Canada from 1878 to 1906 

 are given. It is stated tliat at one time this mineral was mined to the extent 

 of from 20,(KX) to 30,000 tons a year, but is now obtained chiefly as a by-product 

 in the mining of mica, the amount produced being comparatively small, 850 tons 

 in 1900. 



The mineral phosphate industry, L. Aouillon (Hnf/rais, 2'i {1909), Nos. .'lO, 

 pp. 1106, ItOl; //l. pp: H.'/l-l l.'/')). — The world's production of mineral phos- 

 phates in 1908 is given as 5,218.00(t metric tons, of which the United States pro- 

 duced 2,500,000 tons and Tunis 1,2.5S,(X)0 tons. 



The manufacture of superphosphates, I^. Schucht {Die Fabrikation des 

 SupcrpJio.'iphats. Bnmsu-ick, 1909, 3. rev. and enl. ed., pp. VIII-\--'t60, pis. It, 

 figs. 153). — This is a third enlarged and revised edition of this important work 

 (E. S. R., 15, p. 4G2). The information has been brought up to date and a 

 considerable amount of new matter added, including chapters on the utilization 

 of nitrogenous industrial by-jiroducts, the utilization of the nitrogen of the air, 

 methods of analysis of fertilizers as adopted by the German Association of 

 Fertilizer ^lanufacturers in 1907, a review of investigations in the field of 

 fertilizer manufacture, and a select bibliography. 



The formation of oceanic salt deposits, J. H. van't Hoff {Zur liildung dcr 

 Ozcanisdicn Salzahlagcrungcn. Brunsicick, 1909, pt. 2, pp. Vl+90, figs. 15; rev. 

 in Chem. Ztg., 33 {1909), No. 82, p. 150). — This completes the account in book 

 form (E. S. R., 17, p. Ill) of van't Hoff's work on the formation of oceanic salt 

 deposits. This second part deals with lime salts and borates. 



On catalytic fertilizers, G. Bertkand {Ahs. in Chem. Ztg., 33 {1909), No. 11, 

 p. 653; Jour. Soc. Chem. Indus., 2S {1909), No. 13, p. 72^).— This is a note on a 

 paper presented before the International Congress of Applied Chemistry at 

 London. 



Investigations are reported on such substances as manganese, zinc, boron, 

 fluorin, etc., which occur as a rule only in traces in soils and w'hich in the 

 author's opinion affect the fertility of the soil by catalytic action. It is recom- 

 mended that manganese sulphate at the rate of 50 kg. per hectare (44.5 lbs. per 

 acre) and carbonate at 4 to 5 times this rate be employed as a fertilizer, prefer- 

 ably in mixture with manure. 



The fertilizing' value of peat, H. D. Haskins {Jour. Amer. Peat Soc., 1 

 {1908), No. 2, pp. 23-26). — This discussion of the fertilizing value of peat is 

 based upon analyses of a large number of samples of peat from Massachusetts. 



It is pointed out that the percentage of mineral matter in peat is too small to 

 be of any particular significance and that the fertilizing value is due mainly to 

 the nitrogen present. Artificial digestion of peat in permanganate solution 

 indicates that only about one-fourth of the nitrogen present is in immediately 

 available form. A much larger proportion, however, is believed to become 

 available as a result of slow decomposition in the soil. 



Composition of volcanic clay from Java, J. M. Van Kkmmki.kn {Chem. 

 Weekbl., 6 {1909), Nos. 13, pp. 199-215; 15, p. 25 Jf; Ztschr. Anorgan. Chem., 62 

 15149— No. 8—09 3 



