872 EXPERIMENT STATION RECORD. 



The chemical examination of soils and its importance in taxing laud, F. 

 WoHLTMAXN (Zlschr. laudw. Ver. Rheinprtaasen, 05 {lSr>7), No. G, pp. 45-47). 



The conservation of soil and water supply of hill countries in cultivated 

 areas, T. J. McKie {Proc. Amn: Forest. Jssn., 11 {lS07),pp. 137-141). 



The results of efforts at soil improvement on a large scale in the Canton of 

 St. Gallen, K. Sciii'LEH {Landiv. Jahrh. Schweiz, 10 {lS9G),pp. 47-64). 



Management of swamps, R. C. Kedzie {Michigan Sta. Ept. 1S95, pp. 371-376). — 

 A reprint of r.iilletiu 115 of the station (E. S. R., 6, p. 623). 



The nitrifying organisms, A. Stutzek and R. Hartleb (Centhl. Bald, unci Par. 

 All'/., ■] {1S97), Xo. 2-3, pp. 54-57). — The behavior of the organism under various 

 culture conditions is discussed. 



FERTILIZERS. 



Experiments on the preservation of barnyard manure, B. E. 

 DiETZELL {Landw. Vers. Stat., 48 {1897), JVo. 3-5, pp. 163-187).— 1\\ 

 these experiments samx^les of manure were placed iu 12-liter flasks, 

 wbicli were closed with rubber stoppers, carrying tubes through which 

 a current of air could be drawn. In different cases the samples were 

 mixed with litter and with different preservatives, including gypsum, 

 kainit, ''precipitate" (containing 32 per cent water-soluble P^O-, and 

 15.5 ijer cent citrate-soluble P^O.-.)? and double superphosphate (con- 

 taining 38.5 per cent water-soluble P2O5 and 40.2 per cent citrate- 

 soluble P2O5). Air was admitted to some of the flasks and excluded 

 from others. The flasks were kept at a temperature ranging from 10.5 

 to 250 C. from July 5, 1803, to January 30, 1894. The samples of 

 manure were weighed and analyzed at the beginning and end of the 

 experiment, and the ammonia, passing oft" through the outlet tubes of 

 the flasks, was collected in sulphuric acid and determined. 



The details of the experiment are reported in full, and the results 

 show that a mixture of solid cattle excrement and litter supplied with 

 the i)roper amount of moisture and excluded from the access of air did 

 not lose a very large amount of nitrogen or of organic matter. The loss 

 of nitrogen from the same mixture during this period when air Avas 

 admitted varied from 1.8() to 17.13 i)er cent of the original amount of 

 nitrogen present; the dry matter, from 42.82 to 55,82 per cent; and the 

 amount of ammonia produced was from 0.45 to 0.03 per cent of the 

 nitrogen originally present in organic form. The kainit and gypsum 

 were the most ettective of the preservatives in preventing the loss of 

 nitrogen and of organic matter. 



In experiments with calf urine and litter in which the air was ex- 

 cluded the nitrogen of the urine was almost entirely converted into 

 ammonia without the loss either of ammonia or of free nitrogen. In 

 experiments in which air was admitted 16.29 per cent of the nitrogen 

 escaped in the form of free nitrogen. This loss was almost entirely 

 prevented by the use of preservatives. ''Precipitate'' and gypsum 

 appeared to be most efl'ective in preventing the destruction of organic 

 matter and the loss of ammonia, although the nitrogen was almost 

 completely converted into ammonium compounds. 



