FERTILIZERS. 35 



physiological role which magnesium plays in the formation of seeds. 

 The opposite result was obtained with potassium nitrate, The amounts 

 of nitrogen, phosphoric acid, and ohlorin in the crop were practically 

 the same in each experiment. The relative proportions of potash and 

 soda vary to a considerable extent with the relative amounts applied to 

 the soil. Thus, in the experiment with sodium nitrate the crop took up 

 4.32 gm. of potash and 9.17 gm. of sodium. In the experiment with 

 potassium nitrate, the crop contained 9.08 gm. of potash and 5.39 gm. 

 of soda. The amount of lime which the plant contained was not appre- 

 ciably increased by the application of calcium nitrate. The proportion 

 of magnesium in the grain, however, was decidedly increased by the 

 application of magnesium nitrate to the soil. 



Bacteria obtained from manure and their physiological role in 

 the decomposition of manure, S. A. Sewerin (Centbl. Bait. u.Par., 

 2. AM., 3 {1897), Nos. 23-24, pp. 628-633; 25-26, pp. 706-718, figs. 2).— A 

 number of organisms isolated from manure are described and culture 

 experiments with them are reported. The action of some of these 

 organisms was compared with that of Bacillus pyocyaneus on mixtures 

 of horse manure and urine. The decomposition of the manure was 

 measured by the carbon dioxid produced. The results indicate that the 

 organisms were generally effective in reducing the organic matter only 

 when urine was present, but that when the activity of the organisms 

 was once started they not only reduced the organic matter in the urine, 

 but also attacked that of the solid excrement. 



Green manuring and the value of clovers and cowpeas in maintaining soil 

 fertility, H. J. Waters (Missouri Sta. lipt. 1897, pp. 20-33, figs. 2).— Reprinted from 

 Bulletin 34 of the station (E. S. R., 8, p. 969). 



The economic value of farm manures, H. J. Waters (Missouri Sta. Rpt. 1807, 

 pp. 20-25).— Reprinted from Bulletin 34 of the station (E. S. R., 8, p. 969). 



The agricultural value of Thomas slag, Cluss ( ,.'. Congres Internal. Chun. Appl., 

 1896, II, pp. 151-154). — The author quotes experiments at Halle to prove that the 

 citrate soluhility is a reliable indication of the fertilizing value of the phosphoric 

 acid in Thomas slag; th<it the phosphoric acid insoluble in the titrate solutionis 

 practically worthless for fertilizing purposes, and that fusing the slag with silica 

 increases citrate solubility and fertilizing value. 



Study on natural phosphates, II. Lasne (2. Cone/res Internat. Chim. Appl., 1896, 

 III, pp. 24-90). — This article discusses the origin, deposits, composition, and exploi- 

 tation of the principal phosphates of the world, which are grouped in two classes, 

 (1) sedimentary liuophosphates and (2) phosphates of animal origin. The method 

 of analysis used in studying the composition of the different phosphates is given in 

 detail. 



Study on the use of phosphatic fertilizers on the subcretaceous soils of 

 Puisaye, Potter (Ann. Sci. Agron., 1897, II, Nos. 1, pp. 136-160: 2, pp. 161-174). 



The phosphates of Algeria, J. Dugast {Rev. Gdn. Sci. Pares et Appl., 8 (1897), No. 

 19, pp. 769-783, figs. 11). — The origin, nature, extent, exploitation, and agricultural 

 value of these phosphates are very fully treated. 



Phosphatic slags, H. Joulie (2. Congres Internat. Chim. Appl., 1896, II, pp. 167- 

 173). — Gives analyses of different samples and their solubility in ammonium oxalate, 

 acetic acid, and ammoniacal ammonium citrate, according to Millot, with a brief (lis- 



