1917] SOILS FEBTILIZERS. 219 



Experiments with humogen and heated peat, C. T. Gimingham (Nat. Fruit 

 and Cider Inst., Long Ashton [Eng.], Rpt. 1915, pp. 110-113). — Pot experiments 

 with tomatoes on a stiff loam soil to compare bacterized peat and heated peat, 

 when added at rates of 1 lb. 4 oz. and 1 oz. to 20 lbs. of soil, with stable 

 manure, stable manui'e and bacterized peat extract, stable manure and heated 

 peat extract, and stable manure and sodium nitrate are reported. 



It was found that large doses of both bacterized and heated peat gave large 

 increases over the control. As good results were obtained, however, with 

 ordinary treatment for tomato culture. " There seems no reason to attribute 

 the increase in yield to anything more than ordinary manurial properties. . . . 

 One oz. of humogen has apparently given as good results as 4 oz., but the 

 increase over the yield from soil only is not very great in any case and is 

 within the limits of experimental error. . . , The treatment with the water 

 extract of humogen or peat has given no increase whatever." 



Absorption and washing out of nitrogen in fertilizing with, ammonium 

 sulphate, C. H. van Haereveld-Lako {Arch. Suikerindus. Nederland. Indie, 24 

 {1916), No. 6, pp. 177-204, fig. 1; Meded. Proefstat. Java-Suikerindus., 6 {1916), 

 No. 2, pp. 17-U, fig- 1; abs. in Chem. Ahs., 10 {1916), No. 14, p. 1902).— T\\q 

 work of others bearing on the subject is briefly reviewed, and experiments are 

 reported on the absorptive power for ammonia of Java sugar-cane soils to 

 which 0.2-normal ammonium sulphate was added at the rate of 50 cc. per 

 50 gm. of dry soil. 



It was found that the absorption coeflficient of the soils for ammonia varied 

 between 15 and 219 and in most cases was above 140. Soils with a high 

 absorptive power lost less ammonia through washing than those with low 

 absorptive power. If the absorption coefficient is between 80 and 140 there is 

 thought to be little danger of ammonia loss by washing. As a rule a low 

 absorption coefficient of soil accompanied a coarse texture and vice versa. 

 There were, however, exceptions to this rule. When equal amounts of am- 

 monium sulphate of the same concentration were added to different quantities 

 of soil, the amount of increase in ammonia absorption decreased as the 

 quantity of soil used increased. The presence of humus in the soil increased 

 the absorptive power for ammonia. With reference to the exchange of ammonia 

 for calcium, magnesium, potassium, and sodium it was found that the total 

 sum of equivalents of the latter equaled the equivalent of the absorbed 

 ammonia. 



Phosphate rock in 1915, W. C. Phaxen {U. 8. Geol. Survey, Mineral Re- 

 sources of the Umted States, Calendar Year 1915, pt. 2, pp. 227-244^ P^- -?> flff- 

 1). — This report deals with the production, sale, imports, and exports of phos- 

 phate rock during 1915, describes domestic phosphate reserves, gives notes on 

 the conservation of phosphate rock, describes processes for making soluble 

 phosphates, and contains an article by W. B. Hicks on simple tests for 

 phosphate. 



"The quantity of phosphate rock mined in 1915 was 1,935,341 long tons. 

 Compared with the quantity mined in 1914 . . . this was a decrease of about 

 27 per cent. In Florida the decrease amounted to nearly 31 per cent ; in 

 Tennessee it was about 9 per cent ; in South Carolina, 31 per cent ; and in the 

 Western States, 25 per cent. No rock was reported mined in Kentucky in 1915. 

 Stocks on hand at the close of 1915 showed an increase for the entire country 

 amounting to nearly 11 per cent. In Florida the increase amounted to 14 per 

 cent ; in Tennessee it was 6 per cent ; In South Carolina there was a decrease 

 of 34 per cent." " The phosphate rock marketed in the United States in 1915 

 amounted to 1,835,667 lonsf tons, valued at .$5,413,449. Compared with the pro- 



