BOTANY. 419 



The precipitation of solid particles in solutions and the mechanical analysis 

 of soils, G. Nefeuof (Zhin: Oputtn. Agron. [Jour. Expt. Latulw.], 3 {1902), No. 4, 

 pp. 421-449, figs. 7).— To secure a rapid and satisfactory separation of the different 

 grades of soil particles in mechanical analysis of soils, the author recommends rub- 

 bing up the sample with water in a porcelain mortar with a rubber-covered pestle, 

 stirring the thin paste so obtained in water, and measuring the amount of material 

 failing to the bottom of a long narrow cylinder during succesi^ive intervals of time. 

 An apparatus by means of which the successive precipitates may be removed and 

 weighed is descriljed. 



On the combustion of nitrog-en, E. Salvadori (Car. Chim. lUd., SO {1900), II, 

 pp. 3S9-404; (tl'x- in Bnl. Six: Cli'nn. Paris, 3. ser., 28 {1902), No. 18-19, p. 770). — 

 Experiments on the oxidation of nitrogen by burning in a mixture of oxygen and 

 hydrogen are reported, which show among other things that within certain limits an 

 increase of pressure and of the proportion of nitrogen in the gaseous mixture increases 

 the production of nitric acid. A high temperature of the gas at the beginning of the 

 operation and a notable excess of oxygen retard the combustion of nitrogen. 



The artificial production of nitrates, Maizieres {L'Engrais, 17 {1902), Nos.41, 

 pp. 975, 976; 42,jjp.999, 1000). — A discussion of this subject apropos of the announce- 

 ment of the formation of a company to utilize power from Niagara Falls in the pro- 

 duction of nitrates from atmospheric nitrogen by the Bradley and Lovejoy process 

 (E. S. R., 14, p. 119). 



Determination of lactose in milk, Dkgrez {Rer. Gin. Lait, 1(1902), No. 20, pp. 

 469-474)- — Comjiarative tests of several methods are reported. 



A method for the quantiti-ve estimation of ergot in flour, W. Mitlacher 

 (Ztschr. Allg. Oesierr. A path. Yer., 1902, No. 5, pp. 115-126; abs. in Bat. Centhl, 89 

 {1902), No. 14, pp. 411, 412). — Criticises the method of Max Gruber and describes a 

 means foi estimation that is claimed to give results less liable to error. 



On the cause of the injury of platinum crucibles in analysis of phosphates, 

 W. C. Heraeus (Ztsdir. Angeu: ('hem., 15 {1902), No. 37, pp. 917-921). — Investiga- 

 tions are reported which indicate that in the process of igniting precipitates in plati- 

 num crucibles a certain amount of ])hospliorus may be set free, which then combines 

 with the platinum, to the injury of the crucibles. 



Laboratory work, P. Bon.Ime {Rap. An. Sta. Agron. [Muuriliu.'i'], 1901, pp. 9- 

 ^4)- — A brief summary of the chemical work of the Agronomic Station of Mauritius 

 on fertilizers, soils, sugar cane and its products, and miscellaneous materials. 



Directions for laboratory work in physiological chemistry, H. C. Jackson 

 {New York: John Wileij & Sons; London: Chapman d: Half, Ltd., 1902, pp. Y-^62). — 

 According to the author, this book was specially designed as a laboratory guide for 

 students in physiological chemistry, especially the medical students in the University 

 and Bellevue Hospital Medical College, New York. The chemical bodies most 

 important from a physiological point are discussed, and a number of experiments are 

 described in considerable detail. 



Proceeding's of the eighteenth annual convention of the Association of 

 Official Agricultural Chemists ( V. S. Depi. Agr., Bureau of Clionistnj Bnl. 67, pp. 

 184). — This is a detailed report of the proceedings, edited by H. W. Wiley, a sum- 

 marized account of which has appeared (?]. S. R., 13, p. 406). 



BOTANY. 



Report of the consulting botanist, W. Carruthers {Jour. Bath and West and 

 Southern Counties Soc. [England], 4. ser., 12 {1901-2), p. 208). — A brief report is 

 given on several inqui lies which were made by the consulting botanist at the request 

 of members of the society. A seed mixture for permanent pasture was prepared, 

 which consisted of timothy, rough-stalked meadow grass, orchard grass, meadow 

 fescue, meadow foxtail, white clover, and yarrow. A number of weeds are reported 



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