1919] SOILS — FERTILIZERS. 621 



Just within the glacial portion of the glacial and loessial province. Ten soil 

 types of 7 series and 2 miscellaneous types are mapped, of which the Carring- 

 tou loam and silt loam cover 48.6 and 27.8 per cent and the Webster silty clay 

 loam 15.7 per cent of the area, respectively. All of the soils of the county are 

 predominantly dark colored and well supplied with organic matter. 



Soil survey of Henry County, Iowa, A. H. Meyek and T. H. Benton {U. S. 

 Dept. Agr., Adv. Sheets Field Oper. Bur. Soils, 1911, pp. S2, fig. 1, map 1). — 

 This survey, made in cooperation with the Iowa Experiment Station, deals with 

 the soils of an area of 273,280 acres in southeastern Iowa, the topography of 

 which ranges from almost flat to steeply rolling. As a whole the county is 

 well drained. The soils of the county are mainly of glacial drift and loessial 

 origin. Thirteen soil types of 10 series are mapped, of which the Grundy silt 

 loam, Clinton silt loam, and Grundy silty clay loam cover 39.4, 26.9, and 14.9 per 

 cent of the area, respectively. 



Mississippi: Its geology, geography, soils, and mineral resources, E. N. 

 Lowe {Miss. Oeol. Survey Bui. 14 (1919), pp. 3^6, figs. 22). — This is a revision 

 of Bulletin 12, issued in 1915 (E. S. R., 35, p. 213). 



The agricultural soils of the Italian colonies, A. Maugini (Trans. S. 

 Internat. Cong. Trop. Agr. 1914, vol. 2, pp. S81-S96). — This is a summary of 

 data from a large number of sources on the physical and chemical composition 

 of the agricultural soils of Eretria, Somali, Tripoli, and Cirenaica. 



Soils, B. DE Maechand (Union So. Africa Dept. Agr. Rpt. 1917-18, pp. 113- 

 115). — Analyses of 18 samples of soils of five different general types are re- 

 ported, the general characteristics of which are deficiency in lime and phos- 

 phoric acid, together with a relative sufficiency of potash and a fair content of 

 nitrogen. 



Notes on some Poverty Bay soils, B. O. Aston (Jour. Agr. [New Zeal.], 11 

 (1918), No. 4, pp. 196-200, fig. 1). — Analyses of 16 samples representative of the 

 soils of the Poverty Bay region of New Zealand are reported, leading to the 

 conclusion that the majority of these soils show every chemical indication of 

 great natural fertility. The soils of the area are thought to be composed en- 

 tirely of river silts and coarser particles, and the mechanical analyses showed 

 no clay fractions in any case. 



The need and objects of a soil survey in the Punjab, B. H. Wilsdon (Agr. 

 Jour. India, 14 (1919), No. 2, pp. 281-290, pis. 3).— This article deals with the 

 importance of a soil survey in India, and reports mechanical analyses of differ- 

 ent Indian soils as a basis for suggested soil classification. 



A new method of analysis by washing and sedimentation, G. Wiegneb 

 (Landw. Vers. Sta., 91 (1918), No. 1-2, pp. 41-79, figs. 7).— The author de- 

 scribes a method and apparatus for wash analyses, based on the variation of 

 the specific weight of soil grains and especially of disperse particles during 

 sedimentation. A formula corresponding to the theory is given as follows: 



Pvt 

 p=-^, in which p=the weight of the soil after it has settled for a time=t, 

 n 



i;=velocity of sedimentation, 7i=distance of settling, and P=the weight of the 

 soil when t=0 at the beginning of the experiment. The curve of settling, 

 showing quantities of soil and time, could be reproduced for the same soil, 

 and was found to be independent of the height of settling or of the quantity 

 of soil used. Small additions of electrolytes such as potassium chlorid changed 

 the curve entirely. 



The chemical composition of clay obtained by the Atterberg washing 

 method, E. Blanck (Landw. Vers. Sta., 91 (1918), No. 1-2, pp. 85-91). — A study 

 of the chemical composition of clay obtained from six widely different soils 

 by mechanical analysis according to the Atterberg method is reported. From 



