FERTILIZERS. 515 



The percentages of lime vary uuiformly with the productiveness of 

 the soil. 



Washed soils; how to prevent and reclaim them {U. S. Bept. Ayr., Farmers' 

 Bui. 20, 2}p- ^3, Ji(/s. 6).— The uature aud extent of water erosion of agricultural 

 lands are popularlj' discussed, aud the action of orgnuic matter, humus, aud lime in 

 the soil in reducing washing is explained. The means described for preventing 

 washing and for reclaiming gullied lands are deep plowing to increase absorptive 

 power of soils, underdraiuage, hillside ditches, terracing, reforestation, and covering 

 with grasses or similar vegetation. 



Soil moisture {North Dakota Sfa. Bpt. 1893, p. 6).— Determinations of moisture in 

 the surface soils at depths of from 1 to 3 in. and in the subsoil at depths of from 5 

 to 7 in. in a cultivated field on the college farm during 7 months (Ajiril to October) 

 of 1892 and 1893 are reported. 



Moisture of the soil, J. W. Sanborn (Utah Sta. Bpt. 1803, pp. 9i-9S).— The 

 inconclusive results of moisture determinations in upper bench soil before irri'^a- 

 tion, 2 days after irrigation, and 4 days after irrigation are briefly reported. 



Marsh culture experiments conducted at the Royal Swedish Agricultural 

 College in 1893, C. G. Eggerty {Egl. Landt. Akad. Handl. TuUkr., S3 {1894), pp. 

 193-205). 



The exhaustion of soils by crops, L. Grandeau {Jour. A(jr. Prat., 58 {1894), 

 No. 47, pp. 741-744). — A reply to a correspondent, dealing especially with exhaustion 

 of phosphoric acid. 



FERTILIZERS. 



On the preservation of manure, Schmidt and Gerlach [Deut. 



landic. Prense, 21 (1894), No. 62, i^p. 597, 598). — In order to approximate 

 as closely as possible conditions which obtain in i)ractice large amounts 

 (about 3,000 kg.) of manure were used in each of the experiments here 

 reported, and the manure was exposed to the weather on a rubble floor 

 underlaid by sand. Preservative materials were added as follows: (1) 

 Peaty earth, 100 kg.; (2) kainit, 50 kg., and peaty earth, 100 kg.; (3) 

 superphosphate-gypsum, 50 kg. ; (4) " Vogel's preservative, " 50 kg. ; (5) 

 precipitated phosphate, 50 kg., and (6) gyj)sum, 50 kg. The first exper- 

 iment lasted from December 7, 1893, to April 16, 1894. None of the 

 l)reservatives appreciably prevented the total shrinkage of the manures. 

 The kainit aud peaty earth had little effect in preventing loss of nitro- 

 gen. Superphosphate-gypsum and gypsum were far sui^erior to the 

 other materials in this respect, the second giving slightly better results 

 than the first. The losses were in all cases larger than those reported 

 by Holdefleiss for similar experiments conducted during the drier fall 

 season. The results of experiments by the authors at the same season 

 confirm those of Holdefleiss. The difference is ascribed to the leaching 

 out of the preservatives and the valuable constituents of the manure. 

 The results in general indicate that whatever the preservative used it 

 is of first importance to protect the manure heap from excessive moist- 

 ure, which leaches out the valuable constituents and washes down the 

 preservatives to the lower layers of the manure and thus i^revents their 

 effective action. 



