WATER SOILS. 619 



bottom land of uniform character were planted in peas, peas and corn, 

 corn, cotton, and sorghum, and one plat was cultivated like the others 

 but kept free from vegetation. Determinations of nitric nitrogen in the 

 soil of the different plats were made September 30, after about 6 weeks 

 of dry weather, by the following method: "One kilogram of soil was 

 taken about 1 ft. from the plants, in several places, but toward the 

 center of each plat. It was shaken for 6 hours with 1 liter of water, 

 the suspended clay precipitated with 5 gm. of sodium chlorid, one-half 

 liter decanted, evaporated to small balk, and the nitric nitrogen esti- 

 mated in duplicate by the Tiemann and Schulze method." 



The number of milligrams of nitric nitrogen in 1 kg. of soil is given 

 for each plat below : 



Nitric nitrogen in 1 kilogram of soil. 



Mgms. 



Fallow plat I- 010 



Plat planted in peas, growing, pods nearly grown 3.333 



Plat planted in peas, growing, pods about ripe 8. 670 



Plat planted in peas, grown and dead about two or three weeks. 10. 510 



Plat, planted in corn (bard), peas same as above 7.503 



Plat planted in corn ( bard) 340 



Flat planted in cotton, growing 423 



Plat plauted in sorgbum, growing 333 



The data show a much greater accumulation of nitrates in the soil 

 under leguminous plants than in the bare soil or that under corn, 

 cotton, or sorghum. The results indicate u that the micro-organisms of 

 the pea roots assimilate more nitrogen than the plant needs for its 

 growth." Ifthisbetrue, "peas planted with a crop would tend to increase 

 the yield of that crop, unless the peas be so thick as to interfere with 

 the crop's root development, or use up too much water in their growth." 



On denitrification, G. Ampola and O. Ulpiana (Gaz. Chim. Ital, 

 28 (1898), No. 110; abs. in Chem. Ztg., 22 {1898), No. 85, p. <?6i).— The 

 authors isolated from soil a denitrifying organism which differs in char 

 acter from the Bacterium denitrificans agilis of Ampola and Garino, as 

 well as from those of Burri and Stutzer, and Schirokikh. This organ- 

 ism grows well both in presence and absence of air. The name B. den i 

 trificans V has been adopted by the authors for this organism, and its 

 behavior in different media is described. The second organism was 

 isolated from a nitrate solution which had been exposed to the air in the 

 laboratory for some time and was undergoing decomposition with the 

 escape of nitrogen. To this organism the authors give the name B. deni- 

 trijieans VI. The conditions most favorable to the development of both 

 of the organisms are a 0.3 per cent nitrate solution, and a temperature 

 between 30 and 40 ° C. Sunlight has no effect upon them. In pure dis- 

 tilled water the organisms are capable of surviving for 7 months. 

 When dried, B. denitrificans V died within 8 weeks, and B. denitri- 

 ficans VI was alive and active at the end of 5 months. 



The mechanical composition of wind deposits, J. A. Udden (Augnstana Ubr. 

 Pubs., No. 1, pp. 60).— This is a contribution to this subject from the Augustana Col- 

 lege and Theological Seminary at Rock Island, Illinois. 



