218 EXPERIMENT STATION RECORD. 



was much larger for the fertilized soils and stood in close relation to the in- 

 crease in production of dry matter by oats and peas grown on the soils except 

 in case of a fertile clay soil. The author concludes, therefore, that studies of 

 the osmotic properties of the soil may furnish a means of detecting even small 

 amounts of plant food added to the soil. 



Investigations on the water-carrying power (Wasserfuhrung') of the soil, 

 H. PucHNER ilnternat. Mitt. BodcnJc., 1 {1911), No. 2, pp. 99-137).— It is ex- 

 plained that the water-carrying power (Wasserfiihrung) of soils differs from 

 water capacity as ordinarily understood in that it takes account of the capillary 

 water, including hygroscopic water, and also the drainage water. 



In order to obtain a measure of the maximum water-carrying power of soils 

 determinations were made of the percentage by volume and weight of water 

 retained by soils in loose and in puddled (gewachsenen) condition. The so- 

 called puddled condition was obtained by wetting the soils to saturation, 

 shaking until puddled, and allowing them to dry before proceeding with the 

 determination of water-carrying power. In making this determination the soils 

 were placed in tin cylinders provided with wire gauze bottoms covered with 

 filter paper ; the cylinders were allowed to stand in water until the soil was 

 saturated, and then shaken until the soil was puddled, a certain amount of 

 drainage water leaching out through the bottom. The gains in weight of the 

 cylinder calculated in percentages of volume and weight were taken as a 

 measure of the water-carrying power of the soils. 



This method was used in the examination of a large number of tyi^ical 

 Bavarian soils, the more important results of which were as follows: The 

 water-carrying power of the soils was dependent upon other factors besides the 

 size and arrangement of soil particles and the content of colloidal substances. 

 The water-carrying power in percentage of volume was generally considerably 

 larger for the puddled soils than for those in loose condition, whereas in per- 

 centage of weight it was often smaller for the puddled soil. The larger pro- 

 portion of the mineral soils showed a higher water-carrying power in percentage 

 of volume with the loose than for the puddled condition, except in the case 

 of certain soils of peculiar texture, as for example, those rich in organic 

 matter. The surface layer of soil generally, although not always, showed a 

 higher water-carrying power than the lower layer. With the surface soil in 

 loose condition and the subsoil in puddled condition the water-carrying power 

 was higher in percentage of volume for the former, but in percentage of weight 

 the reverse was true. Emphasis is placed upon the importance of study of 

 questions of the relative proportion of capillary and drainage water of the 

 soil, and it is believed that the centrifugal method of Briggs and McLane 

 (E. S. R., 19, p. 416) gives the most promise for such determinations. In 

 several trials with soils of varying composition it was found that the drainage 

 water decreased with the clay and humus content and increased with the sand, 

 and the finer the sand the greater the drainage. 



A contribution to the subject of the hygroscopic moisture of soils, C. B. 

 LiPMAN and L. T. Sharp {Jour. Phys. Chcm., 15 {1911), No. 8, pp. 709-722). — 

 In view of the confirmation by H. E. Patten and F. E. Gallagher of the Bureau 

 of Soils of this Department (E. S. R., 19, pp. 1118) of the principle, enunciated 

 by Knop and Schiibler, " that the power of soils to absorb hygroscopic moisture 

 from a saturated atmosphere decreases with a rise in temperature and increases 

 with a decline in temperature," and the contrary conclusion by E. W. Hilgard 

 " that not only does the power of soils to absorb hygroscopic moisture not' 

 decrease with a rise in temperature, but that it actually increases provided the 

 atmosphere is saturated," the authors undertook not only to investigate 

 further the relation of temperature to absorption of hygroscopic moisture by 



