758 EXPERIMENT STATION RECORD. 



previous bulletin ( E. S. R., L4, p. 1056) a study was made of the rate of nitrification 

 of barnyard manure, dried blood, cotton-seed meal, iish, ammonium sulphate, and 

 bone in rich and poor sandy soil and in rich and poor clay soil from the college 

 farm. 



" In soils taken from the field in the natural state, the rank of the fertilizers after 

 4 or 5 weeks varied somewhat from soil to soil. The amount of nitrogen nitrified in 

 the form of cotton-seed meal being placed at 100, the variations were as follows: 

 Ammonium sulphate, 13 to 127; dried blood, 70 to 120; fish, 85 to 190; bone, 22 to 

 4.">. Some of this variation may lie due to variation in the activity of the organisms. 

 With 16.1 gm. dried barnyard manure to 500 gm. soil, less nitrification took place in 

 4 or 5 weeks in 3 of the soils than when nothing was added, in the fourth soil, 0.5 

 per cent of the nitrogen was oxidized. With smaller amounts of barnyard manure, 

 different results might be obtained." 



Nitrification of ammonia fixed by chabazite, W. A. Withers and G. S. Fkaps 

 (North Carolina Sta. llpl. 1903, pp. 55, 56). — In a study of the rate of nitrification of 

 ammonia fixed by chabazite representing zeolitic silicates of the soil it was found 

 that the ammonia so fixed was nitrified more rapidly than ammonium sulphate or 

 cotton-seed meal, indicating that zeolitic silicates in soils may possibly aid in the 

 nitrification of ammonium sulphate by fixing a portion of the salt. 



The nitrification of the ammonia of the soil, L. Grandeau (Jour. Agr. Prat., 

 v. ser., 8 (1904), No. 5 J, pp. 824, 825). — Experiments by Wagner and others are cited 

 to show that nitrification of ammonium salts is more rapid the smaller the amount of 

 the salts and the more thorough their diffusion in the soil. 



Experiments on the nitrification of various nitrogenous fertilizers, L. 

 Grandeau (Jour. Agr. Prat., n. ser., 9 (1905), No. 3, pp. 78, 79). — A brief popular 

 discussion of this subject based upon the experiments of P. Wagner on the relative 

 fertilizing value of different nitrogenous materials, and of J. Stoklasa on the relative 

 nitrifying power of different soil organisms. 



FERTILIZERS. 



Town stable manure: Its chemical composition and the changes it under- 

 goes on keeping, B. Dyer (Jour. Agr. Set., 1 (1905), No. 1, pp. 108-113). — Analyses 

 of 7 samples of London stable manure prepared with peat moss and straw or mix- 

 tures of the two as litter are reported, both in the fresh state and after storage in 

 large heaps in an open field from summer to the following spring. The variable 

 character of such manure and the changes which it undergoes in storage are briefly 

 discussed. 



Rendsburg fecal fertilizer, H. Wehnert (Milt. Prut. Landw. GeselL, 19 (1905), 

 No. 53, pp. 327-329). — This fertilizer is a mixture of fecal matter, street sweepings, 

 and garbage. It is of variable composition, containing on the average about 1 per 

 cent of nitrogen and phosphoric acid and 0.5 per cent of potash. 



The "Wonderfontein caves, H. Ingle (Transvaal Agr. Jour., 3 (1905), No. 10, 

 pp. 217-221, pis. 3). — A brief report on the bat guano deposits of these caves. 



Two years' comparative tests of Peruvian guano and ammoniated super- 

 phosphate, A. Arnstadt (Deut. Landw. Presse, 32 (1905), No. 3, pp. 17, 18).— The 

 experiments were made with barley and potatoes. The fertilizers used were crude 

 Peruvian guano containing 7 per cent of nitrogen, 18 per cent of phosphoric acid, 

 and 2 to 3 per cent of potash; a modified Peruvian guano containing 7 per cent of 

 nitrogen, 9.5 per cent of phosphoric acid, and 1 to 2 per cent of potash; and ammo- 

 niated superphosphate containing 9 per cent each of nitrogen and phosphoric acid. 

 In both years and with each crop the Peruvian guano proved superior to the ammoni- 

 ated superphosphate. 



Calcium cyanamid, A. D. Hall (Jour. Agr. Sci., 1 (1905), No. 1, pp. 146-148).— 

 The preparation and character of this material are briefly described, and experiments 



