SOILS FERTILIZEES. 323 



per square meter. Clilorid of lime was often effective, but not unless used at 

 rates of 300 gm. or more per square meter. 



The daily course of atmospheric pressure in the soil, R. Bornstein 

 (Verhandl. Deut. Phijs. GeselL, 13 (1911), No. U, pp. 511, 512; Pliys. Ztsclir., 

 12 (1911), No. 18, pp. 771-776, figs. 4; Met. Ztschr., 28 (1911), No. 12, pp. 561- 

 566, figs. .',; abs. in BeiU. Ann. Phys., 35 (1911), No. 22, pp. 1230, 1231; Pro- 

 metheus, 22 (1911), No. 1143, Sup., p. 201, fig. 1). — The atmospheric pressure 

 in the soil at a depth of 1 meter was observed during 6 months (February to 

 July, inclusive) of 1911 by means of a special form of barograph. A com- 

 parison of these observations with observations made in the free air showed 

 a parallelism between variations in the soil and the air with this exception, 

 that the daily forenoon variations were greater and the afternoon variations 

 were smaller in the soil than in the air. 



An effective method of preventing the erosion of hill lands, W. B. Mercieb 

 (U, 8 Dept. Agr., Bur. Plant Indus. Doc. 706, pp. 7, figs. 5). — The author gives 

 directions for laying out a system of broad tei'races — a combination of the 

 hillside ditch and the true terrace — for the control of water on hill lands. It 

 is believed that this system is of particular value in the cotton-growing States 

 where large areas " are badly in need of some method of preventing the land 

 from washing away." 



The agricultural side of peat bog utilization, C. A. Davis (Jour. Amer. Peat 

 Soc., 4 (1911), No. 2, pp. 97-100). — The status of swamp reclamation for agri- 

 cultural purposes in the United States and Europe is briefly discussed and at- 

 tention is called particularly to the possibility of utilizing drained peat beds 

 for the production of farm power. 



Results of cooperative experiments with fertilizers on swamp soils, R. 

 HAKCorRT (Ann. Rpt. Ontario Agr. and Expt. Union, 32 (1910), pp. Ji4, 45). — 

 Coopex'ative experiments which showed especially the need of potash are 

 briefly reported. 



Stable manure as a source of nitrogen, phosphoric acid, and potash, A. G. 

 DoiAEENKo (Izv. MosTcov. Selsk. Klioz. Inst. (Ann. Inst. Agron, Moscou), 17 

 (1911), No. 2, pp. 266-275, figs. 3). — The results of pot experiments with stable 

 manure from different sources showed that the manure was poorly utilized as 

 a source of nitrogen. The phosphoric acid was more assimilable, and the 

 potash was the most readily available of the 3 constituents. Pigeon manure 

 contained nitrogen and phosphoric acid in very available form. 



[Fertilizing value of peat], A. E. Whitson (CampbeWs 8ci. Farmer, 4 

 (1911), No. 12, pp. 11, 12). — In experiments on very poor sandy soil at Sparta, 

 Wis., 25 loads of peat per acre combined with a basal fertilizer of potash and 

 phosphoric acid gave better results during 2 years than 15 loads per acre of 

 manure, indicating that peat can be used to advantage on such soils. 



The fertilizing value of certain nitrogenous substances, A. Geegoire and 

 J. Hendrick (Ann. Gembloux, 21 (1911), No. 12, pp. 595-605; abs. in Engrais, 

 26 (1911), No. 50, pp. 1385-1387). — Pot experiments on sandy soil with Prussian 

 blue, residue from the manufacture of potassium ferrocyanid, crude ammonia, 

 calcium cyanamid, ground raw and roasted leather, wool, and ammonium sul- 

 phate, showed that with timothy the nitrogen of the pure wool used was 87 

 per cent as effective during the first year as that of ammonium sulphate, that 

 of crude ammonia 36 per cent as effective, and that of calcium cyanamid 73 

 per cent as effective. Prussian blue was not only without effect as a fertilizer 

 but injured the plants slightly. The residue from manufacture of potassium 

 ferrocyanid was practically of no fertilizing value. Raw ground leather was 

 of no fertilizing value, but the nitrogen of the ground roasted leather was 20 

 per cent as effective during the first year as that of ammonium sulphate. 

 28727°— No. 4—12 3 



