SOILS FERTILIZEKS. 125 



•' lu two experiments by the paraffined wire baslvet method, with white quartz 

 sand which had been digested with acid, sodium, when supplementing a 

 deficient amount of potassium, affected the growth similarly as in the solution 

 experiments." 



The partial substitution of potassium, by sodium as a plant food, K. L. 

 Hartwell, H. J. Wheeler, and F. K. Pember {Abs. in Science, n. ser., 21 

 (1908), No. 6S6, pp.' 298, 299).— This is an abstract of a paper presented at the 

 Chicago meeting of the American Chemical Society, the essential features of 

 which are given in the paper noted above. 



What is the relation of the increase in yield of barley produced by phos- 

 phatic fertilizers to the phosphoric acid content of the soil? F. 1'ilz iZtschr. 

 Landic. Versuchsiv. O.'^ten:, 11 (1908), A o, /, /;/>. 36-51; ah.s. in Chcm. Zentbl., 

 1908, I, Xo. 8, pp. 7.J9, 7()0; Jour. Clicni. H(m: [London], 9) (1908), No. .7//7, //, 

 /). .'i,23). — From the results of a large number of observations on the relation 

 Ix'tween increased yield of different varieties of barley produced by application 

 of phosphatic fertilizers and the phosphate, nitrogen, and potash contents of the 

 soils the conclusion is drawn that the higher the phosphoric acid content of the 

 soil the greater is the benefit resulting from the application of phosphatic fer- 

 tilizers. Suiierphosphates were in general more effective on rich soils (contain- 

 ing over 0.2 per cent each of nitrogen, jMitash, and i>hos|)horic acid) than on 

 poor soils (containing less than these percentages). This explains the fact 

 often observed in practice that the use of phosphatic fertilizers on poor soils 

 frequently results in a depression in yield and poor ripening of barley. 



Phosphorus and humus in relation to Illinois soils, C (J. Hopkins (Illinois 

 stfi. Cirr. 116, pp. 27). — This is an address which was delivered before the Illi- 

 nois State Farmers" Institute, and discusses the improvement of the couunon 

 prairie soils of the Illinois corn belt by means of rotations and the use of tine- 

 ground limestone, rock phos])hate, and organic manures, thi' main object being 

 to increase the phosphorus and humus content of the soils. 



On the behavior of minerals in soils, P. Vinassa ue Ivegny (Std.:. Spei: Aijr. 

 llal., Jfl (1908), No. 1, pp. J/-77). — The results of investigations, i)articularly 

 those of the Bureau of Soils of this Department, and of Delage and Lagatu 

 (E. S. R., 17, pp. 226, S41), bearing on the solubility of various mineralogical 

 constituents of soils are summarized and discussed. A bibliography of 48 refer- 

 ences to literature on the subject is given. 



Effect of lime and gypsum on the solubility of potassium in feldspars, 

 F. W. Morse and B. E. Curry (.l^^.s-. in Sriencc, n. ser., 27 (1908), No. 686, p. 

 29.')). — This is an abstract of a paper presented at the Chicago meeting of the 

 American Chemical Society. The authors found that lime and gypsum in con- 

 tact with feldspar increased the solubility of i)otassium. The fact that this 

 effect was not observed when ordinary clay soils were treated in the same way 

 is attributed to the removal of potassium from solutions by the absorbent power 

 of the clay. 



Note on the effect of lime upon the availability of the soil constituents, 

 F. B. Guthrie and L. Cohen (Agr. Gaz. N. S. M'alcs, 18 (1907), No. 12, pp. 952- 

 956; UaiKuii. Planters' Mo., 27 (1908), No. 1, pp. .i2-37).— Experiments on the 

 solubility in water and 1 per cent citric acid of phosphoric acid and potash in 

 light sandy soil, garden loam, and very stiff clay before and after treatment for 

 one month with 1 per cent of freshly slaked lime, as well as the changes which 

 the nitrogen underwent as a result of such treatment, are reported. 



The water-soluble phosphoric acid decreased during the experiment in all of 

 the soils and the potash in the clay soil. The amount of water-soluble plant 

 food, however, was larger in the limed than in the unlimed soils, but only in the 

 sandy soil did the liming increase the proportion of water-soluble phosphoric 



