SOILS FERTILIZERS. 129 



of the solution, wliile the second Iftwers the alkalinity and the third gives an 

 acid reaction. 



The action of podzol soils on raw phosphates, A. G. Doyarenko [Izv. Mos- 

 kov. Selsk. Ehoz. Inst. [Ann. Inst. Agron. Moscou], 15 {1909), No. 2, pp. 224- 

 229). — In view of the fact that raw phosphates give good results as fertilizer 

 on podzol soils, experiments were made to determine whether such soils exert 

 any special action upon the solubility of the phosphates. The experiments, 

 however, gave negative results since less phosphoric acid was dissolved by 

 means of acetic acid from a mixture of soil and phosphate than from the two 

 treated separately. 



Phosphorus and humus in relation to Illinois soils, C. G. Hopkins {Ann. 

 Rpt. III. Farmers' Inst., IS {1908), pp. 177-19',).— This article sets forth quite 

 fully the author's well known views regai'ding the use of raw rock phosphate 

 for the improvement of certain classes of Illinois soils. 



Florida phosphates, A. Vogt (Amcr. Fcrt., 31 (1900), Xo. -'/, pp. 5-7). — The 

 origin, formation, and discovery of these phosphates are briefly discussed. 

 The author claims to have discovered the phosphate deposits of Florida in 

 1888. 



Russian superphosphates {Chem. Trade Jour., .',5 {1909), No. 1157, p. 80). — 

 A brief note is given upon an inquiry by the Russian agricultural department 

 into the possibility of cheapening the supply of phosphatic fertilizers and on 

 extensive cooperative fertilizer experiments which have been undertaken by 

 the department. A congi-ess has been called to consider the question. 



The reduction of bones by alkalis, K. D. Sokolov (Izv. Moskov'. Selsk. Khoz. 

 Inst. [Ann. Inst. Agron. Moscou], 15 (1909), No. 2, pp. 219-223).— By treating 

 coarsely gi'ouud bones with various alkaline mixtures, either heating for 7 

 hours or treating in composts, it was found that mixtures of ashes and calcium 

 hydroxid or of alkali cai-bonate and calcium hydroxid under all conditions 

 tested increased to a marked extent the citrate solubility of the phosphoric 

 acid (77.7 to 87 per cent of the total phosphoric acid). 



The amount of free lime and the composition of the soluble phosphates in 

 basic slag, C. G, T. Mokison (Contrih. Lab. Rothamsted Expt. Sta., 1909, pp. 

 161-170, figs. 2; reprinted from Jour. Agr. Sci., 3 (1909), No. 2, pp. 161-170, 

 figs. 2). — By shaking the slag for a considerable time with distilled water free 

 from carbon dioxid and titrating with standard acid, using phenolphthalein as 

 an indicator, it was found that the free lime present varied from about 5 to 6 

 per cent. 



Further chemical studies of the slag gave results confirming Kroll's conclu- 

 sion " that the principal constituent of basic slag is a compound hitherto un- 

 known, consisting of a silico-phosphate of lime and ferrous iron." The formula 

 indicated by the analytical data is (CaO)5FeO. P^OsSiOo. 



" The absence of ci-ystals of tetracalcium phosphate, which were undoubtedly 

 obtained from basic slag by earlier observers, and the low percentages of free 

 lime now found to be present in the slag, may be correlated with the increased 

 percentage of phosphoric acid in slags of modern manufacture, less lime being 

 nowadays employed in the dephosphorization process than formerly." 



On the behavior of aluminum and iron phosphate, D. N. Fbianishnikov 

 {Izv. Moskov. Selsk. Khoz. Inst. [Ann. Inst. Agron. Moscou], 15 (1909), No. 1, 

 pp. 16-23, figs. -J). — In the pot experiments with oats, barley, and buckwheat 

 reported, the addition of calcium carbonate always exerted a depressing action 

 on the assimilability of the phosphoric acid of these phosphates. In laboratory 

 experiments it was found that the addition of calcium carbonate reduced the 

 amount of phosphoric acid dissolved from these phosphates by water alone or 

 water charged with carbon dioxid. 



