624 EXPERIMENT STATION RECORD. 



duced much smaller yields for the same application of nitrogen than that which 

 had been preserved without change. The author therefore concludes that it is 

 of practical importance to avoid carrying over a supply of the cyanamid from 

 one season to another. 



In agreement with the results of other investigators the author found that the 

 cyanamid should be well mixed with the soil before seeding and not applied as a 

 top-dressing. When thoroughly incorporated with the soil any dicyandiamid 

 which may be formed is quickly converted into ammonia and nitrified. 



On the formation and decomposition of calcium cyanamid, M. Le Blanc 

 and M. Eschmann {Ztschr. ElcUrochem., 17 {1911), No. 1, pp. 20-3.'/, figs. 5). — 

 This article discusses the theoretical reactions occurring in the formation and 

 transformation of calcium cyanamid, describes methods of analyzing the prod- 

 uct, and reports experiments on the equilibrium weights of calcium cyanamid 

 and its products. 



The need of the soil for potash, P. Hoc (Prog. Agr. et Vit. {Ed. VEst- 

 Centre), 31 {1910), No. 51, pp. 762-76^). — The author questions the correctness 

 of the commonly accepted percentage of potash considered essential to a pro- 

 ductive soil, and cites cases of soils containing much more than 0.2 per cent of 

 potash which were nevertheless much benefited by potash fertilizers. He thinks 

 the limit should be raised to from 0.3 to 0.35 per cent at least for intensive 

 culture. 



Kainit, Maurecourt {Engi'ais, 26 {1911), No. 2, pp. J/l-H). — It is stated that 

 the total amount of kainit used for agricultural purposes in 1909 was 2,578,971 

 tons. Of this Germany consumed 1,749,389 tons and the United States 404,611 

 tons. 



German potash situation {Chcin. Trade Jour., .}S {1911), No. 1236, pp 

 77-79). — The present status of the German potash industry is discussed with 

 special reference to the controversy over American contracts for potash salts. 



German potash, prices, T. J. Albert {Daily Cons, and Trade Rpts. [U. S.I, 

 n. ser., 1 {1910), No. If9, pp. 652, 653). — The prices adopted by the new potash 

 syndicate are given. 



Our supply of phosphate and its origin, A. J. Woolman {III. Agr., 15 {1911), 

 No. Jf, pp. 36-.'i2, figs. 3). — This is a compiled article on the subject, dealing more 

 particularly with Tennessee i)hosphates in view of the fact that these deposits 

 are more accessible to the inland regions of the United States and are exported 

 to a less extent. Estimates of the available supply of phosphate in the United 

 States are given as follows: South Carolina 3,000,000 tons, Florida 15,000,000 

 tons, Tennessee 103,000,000 tons, and western deposits 100,000,000 tons. Empha- 

 sis is laid upon the importance of the conservation of this resource. 



Tennessee phosphate in 1910, J. Ruhm, Jr. {Engin. and Min. Jour., 91 

 {1911), No. 2, pp. 123, 12 J/). — It is stated that there was renewed activity in 

 the Tennessee phosphate industry in 1910, and greater utilization of low-grade 

 phosphates following experiments by the U. S. Geological Survey. Methods 

 were introduced and developed for saving material formerly left unmined or 

 thrown back into the spoil banks, and a ready market was established for 

 the tailings, which were formerly dumped into the creeks or used for filling. 

 This was a result of work of several of the experiment stations showing the fer- 

 tilizing value of fine-ground rock phosphate. 



Phosphates in Montana, H. S. Gale {U. 8. Geol. Survey Bui. 470-A, pp. 9, 

 figs. 2; Amer. Fert., 3J, {1911), No. 2, pp. 15-18, figs. 2).— Deposits which have 

 recently been discovered in the canyon of the Big Hole River southwest of 

 Butte, Montana, are briefly described. 



Analyses of samples of the phosphate show phosphoric acid varying from 

 14.1 to 35.09 per cent, and indicate the presence of some high-grade phosphate 



