W ATER SOILS. 8 5 7 



Fresenius (Jour. Lamlir., 52 i 1904), No. }, pp. S55-S93; abs. in Chem. Centbl., 1905, 

 /, No. 2, i>. 115). — The water requirements of oats, beets, and clover were studied in 

 large vegetation boxes, a record being kept of the precipitation, drainage water, 

 fluctuations of weight of the boxes (evaporation), and temperature of air ami rain- 

 fall from April, 1002, to March, 1903, inclusive. The fertilizing matter (sulphuric 

 acid, nitric acid, phosphoric acid, lime, magnesia, and potash) removed in the 

 drainage water was also determined. Detailed data are reported and summarized, 

 but no general conclusions are drawn. 



Soils, E. Ramann ( Bodenkunde. Berlin: ./"/ins Springer, wo:,, /,/,. All I 431). — 

 The second revised and enlarged edition of this work, which first appeared in 1895. 

 The main subdivisions of the hook are soil constituents, weathering, the most impor- 

 tant rocks and minerals and their decomposition, soil organisms, organic residues of the 

 soil, chemistry of soils, physics of soils, soil covering, physiography of soils, mapping 

 of soils, principal soil types, climatic soil zones, and relation of soils and plant, life. 



Judging the more important physical properties of soils on the basis of 

 mechanical analysis, J. Hazard ( Landw. Vers. Slat., 60 ( 1904), Nos. 5-6, )>/>. 449- 

 474,. fi'j- 1; abs. hi Chem. Centbl., 1905, I, No. 4, p. 291).— Using the results of 350 

 examinations of soils made by methods described in a previous publication (E. S. 

 R., 12, p. 1023), the author attempts to trace the relation between tin- size and phys- 

 ical character of the particles and the productiveness of a soil. 



The principal conclusions reached are that the soil skeleton (particles 20 to 0.15 

 nun. in diameter) of sand and loam soils is of little importance as affecting water 

 capacity and capillarity; the particles less than o. ol mm. in diameter separated by 

 the Schone apparatus from clay and humus soils are not alone responsible for the 

 productiveness of such soils, the latter being favorably influenced also by the silt 

 (0.01 to 0.05 mm. in diameter), sand (0.15 mm.), and the capillary spaces due to 

 coarser particles. Coarse sharp-angled rock fragments (20 mm. in diameter) increase 

 the water capacity and cultural value of soils so long as they do not exceed one- 

 fourth of the air-dry weight of the soil; rounded stones produce like results so long 

 as they do not exceed one-eighth of the air-dry weight of the soil. 



The most important constituents to be determined by mechanical analysis are 

 stones and pebbles (over 20 mm. in diameter), gravel and sand (2.0 to 0.15 mm. in 

 diameter), particles less than 0.15 mm. in diameter, and, when necessary, the tine 

 sand (0.15 to 0.05 mm. ). The cementing power may be determined with satisfactory 

 accuracy by allowing a weight to fall on dried briquettes of the soil. The amount of 

 easily determined iron compounds gives a measure of the permeability of the subsoil. 

 In the chemical determination of the lime requirements of the soil, account must be 

 taken of lime aggregates due to previous liming which may occur in the unsieved 

 soil. 



The available plant food in soils, II. Ingle (Jour. Chun. Soc. [London], S7 

 (190')), No. 507, pp. 43-55, jigs. 2). — Pot experiments during 1001 and 1002 with bar- 

 ley, turnips, and horse beans on soil from the (iarforth Experimental Farm extracted 

 for 7 days with 1 per cent citric acid, as in Dyer's method, are reported. Experi- 

 ments were also made with the original soil, water-washed soil, and extracted soil with 

 lime, lime and potash, lime and phosphate, and lime, potash, and phosphate. The 

 citric-acid soluble plant food in the soil, and the yield and the potash, phosphoric 

 acid, and silica content of the whole plants and of the straw and seed are reported. 



"The general conclusion to be drawn from the results of this investigation is that, 

 whilst Dyer's method affords a satisfactory means of measuring the relative amounts 

 of available plant food in two soils at a given time, it may not accurately gage their 

 relative fertility, inasmuch as it leaves undetermined the relative rapidity with which 

 the available plant food is renewed by the processes of weathering and decay. How- 

 ever, under similar climatic conditions, the rate will probably be approximately the 

 same for most soiis. 



