330 EXPEBIMENT STATION EECOBD. 



pirical standard was 69.14 gm. of sulphuric acid and tlie theoretical standard 

 ou the basis of tricalcium phosphate was 64,325 gm., and on the basis of apatite 

 70.424 gm. This is taken to indicate that for the phosphate used the apatite 

 content should be taken as a basis for the establishment of a standard. 



A special type of natural phosphate, I. V. Iakushkin {Iz RezuVt. Veget. 

 Opytov Lab. Rahot, 9 (1913), pp. 92-1S6, figs. iO).— Further cropping experi- 

 ments with a special type of natural phosphate (E. S. R., 29, p. 41S) are re- 

 ported. 



Tests of the inside and outside parts of this phosphate showed the outer 

 parts to be the most available. This is taken to indicate that a more intensive 

 secondary process is a necessary factor in the accumulation of semisoluble 

 phosphoric-acid compounds in raw phosphates. Samples of a relatively avail- 

 able raw phosphate taken from different depths showed no difference in their 

 behavior toward crops. 



The size of the cereal crop when fertilized with raw phosphate was found to 

 depend ou the content of phosphoric acid soluble in citric acid. In all cases 

 of apparent deficiency of phosphoric acid in the deeper layers the crops showed 

 a low content of easily soluble phosphoric acid. The transition from deficient 

 to sufficient nourishment of crops was always closely related not only to 

 the significant increase in the harvest but also to the content of easily soluble 

 phosijhoric acid compounds in the crops. The percentage of total phosphoric 

 acid, esi)ecially of phosphorus combined with protein, decreased in certain 

 cases. Excessive nourishment, while it increased the content of all forms of 

 phosphorus in the crop, did not increase tht> size of the harvest. 



Preparation of enriched superphosphate with precipitated phosphate, K. N. 

 SHNTiT.sov {Iz RezuVt. Vcget. Opytov Lab. Robot, 9 (WIS), pp. 67-.''7).— Studies 

 of the preparation of enriched superphosphate were conducted, tlie phosphoric 

 acid of a water solution of superphosphate being precipitated and treated with 

 sulphuric acid. With a sample of Viatka phosphate the author succeeded In 

 obtaining a phosphatic precipitate containing from 30 to 40 per cent pho.sphorIc 

 acid and an enriched superphosphate containing from 18.4 to 32.3 per cent 

 total phosphoric acid, of which from 14.4 to 31 .8 per cent was soluble in water. 



Palmaer's phosphate, D. N. Pbianisknikov and I. V. Iakushkin (.Iz RezuVt. 

 Yegct. Opytov Lab. Robot, 9 (19 J 3), pp. 152-159). — Cropping experiments with 

 oats, millet, and flax to determine the value of Palmaer's phosphate as a ferti- 

 lizer are reported. 



It was found in all cases that this phosphate was well utilized and was supe- 

 rior to all other sources of phosphoric acid useii, including superphosphate 

 and Thomas slag. Analyses of the millet crop showed that the phosphoric acid 

 of Palmaer's phosphate was utilized as well as that of monocalcium phosphate, 

 and it was markedly superior to superphosphate for flax. It is thought that 

 Palmaer's phosphate will have a much better effect on sandy soil tending to be 

 acid than superphosphate. In chemical studies the phosphoric acid of Pal- 

 maer's phosphate was found to be much more soluble in Potormann's reagent 

 than that of Thomas slag. 



Welter's phosphate and its components, N. A. UspenskiI (Iz RezuVt. Veget. 

 Opytov Lab. Robot, 9 (1913), pp. 359-377). — Experiments to determine the effect 

 of the Wolter process on Kasan phosphorite with reference to the uvail- 

 ablUty of the resulting phosphate are reported. This process involves the 

 fusion of the phosphorite witli sodium sulphate, carbon, and calcium carbonate. 



The Kasan phosphorite contained 40 per cent calcium oxid and 5 per cent 

 carbon dioxid. A 3-hours' fusion of this pho.'^phorlte with sodium sulphate and 

 carbon yielded a product, the phosphoric acid of which was as available to 

 millet in sand cultures as that of Wolter's phosphate or Thomas slag. An ex- 



