SOILS FERTILIZEKS. 619 



The penetration of the soil by frost and its importance in relation to plant 

 growth and soil culture, W. Naeglek (Wetter, 28 (1911), No. 9, pp. 210, 211).— 

 This is a brief compilation of information on this subject. 



Aeration of the soil by earthworms, J. N. Fkiend (8ci. Prog. Twentieth 

 Cent., 6 (1912), No. 23, pp. 393-401, fig. 1).—A study of the carbon dioxid 

 exhalation of Lumhricti^ rubellus, AUolobophora longa, Aporrectodea chlorotwa, 

 Octolasium cyaneum, and Dendrobaeua showed that the amount of carbon 

 dioxid exhaled was not proportional to the body weight of the worms, but 

 increased as the size of the worms decreased. It was practically the same as 

 that of human beings in a similarly quiescent state. It increased with a rise 

 in temperature and under the influence of daylight. 



The ways in which the worms mechanically and chemically promote aeration 

 in the soil are explained. It was found that the ferric oxid of the sand had 

 been dissolved in the castings of the worms, suggesting that this may be an 

 important factor in rendering plant food available. 



The flow of water and air throug'h soils, J. W. Leather (Join: Agr. ScL, 

 4 (1912), No. 3, pp. 303, 304). — Referring to a previous article by Green and 

 Ampt (E. S. R., 25, p. 620), it is pointed out that Poiseuille's formula is not 

 applicable to soils. 



Laboratory apparatus for the determination of the absolute water capacity 

 and of the complete water capacity (also rate of percolation and of ab- 

 sorption) of soils, F. Maeshall (Lcmdw. Vers. Stat., 76 (1912), No. 1-2, pp. 

 125-134, figs. 5). — Special forms of apparatus for determining "the absolute 

 water capacity," by means of the amount of water absorbed by capillarity, and 

 " the complete water capacity," measured by the amount of water retained 

 when the soil is saturated with water added at the surface, are described, and 

 their use is explained as is the application of the data thus obtained in the 

 calculation of the rate of percolation and of absorption of soils. 



Tests of the method described on different mixtures of sand and clay showed 

 that the rate of capillary rise of water decreased and the water capacity 

 increased with the proportion of clay. 



The author is of the opinion that, although laboratory determinations of 

 the water capacity of the soil have no direct practical value since the soil in 

 such cases is not in its natural state and conditions are abnormal, they may 

 be useful in studying the relationships of different soil groups. 



Investigations on the amount and composition of drainage water, M. Gee- 

 LACH (Mitt. Kaiser WiJliehns Inst. Landiv. Bromherg, 2 (1910), No. 4, pp. 319- 

 387, figs. 4; 3 (1911), No. 5, pp. 351-381; Illus. Landw. Ztg., 31 (1911), No. 80, 

 pp. 755, 756; abs. in Zentbl. Agr. Chem., 39 (1910), No. 10, pp. 647-653; Internat. 

 Inst. Agr. [Rome], Bill. Bur. Agr. Intel, and Plant Diseases, 2 (1911), No. 11- 

 12, pp. 2469, 2470). — Observations extending over several years on the amount 

 and composition of field and lysimeter drainage waters as affected by such 

 factors as precipitation, and the character of the soil, fertilizers, and cropping, 

 are reported in considerable detail. See also a previous note (E. S. R., 24, 

 p. 711). 



Ten lysimeters 2 meters square, 1.2 meters deep, and containing 4 cubic 

 meters of soil, were used. The construction of these lysimeters is fully de- 

 scribed and illustrated. Five of the lysimeters were left without fertilizer and 

 five were fertilized with calcium carbonate, ammonium sulphate, and dipotas- 

 sium phosphate. The cropping was fallow the first year, followed in order 

 during the four succeeding years by potatoes, oats, rye, oats. Five different 

 kinds of soil, varying from moor soil to light, sandy loam, were used. 



