No. 1, August, 1921] SOIL SCIENCE 81 



529. ViLLEDiEU, M. ET Mme. De la non-toxicite du cuivre pourles moisissures en gene- 

 ral et pour le mildou en particulier. [The non-toxicity of copper for molds in general and for 

 mildews in particular.] Compt. Rend. Acad. Sci. Paris 171: 737-739. 1920. — Most ordinary 

 molds may be cultivated in 1, 2, 5, or 10 per cent solutions of cuproammonium citrate, a salt 

 which is slightly acid, very soluble in water, and contains 15 per cent metallic copper. Penicil- 

 lium lives well in nutritive agar saturated with this salt. The toxic action of copper sulphate 

 is found to be due entirely to the free sulphuric acid produced in solution. Phylophlhora 

 infestans will grow in solutions of copper ammonium citrate up to a strength of at least 0.1 per 

 cent. — C. H. Farr. 



530. Wieler, a. Rauchschaden bei Kokereien. [Smoke injury from coke ovens.] Jah- 

 resber. Ver. Angew. Bot. 16: (i4-7(). 1918. — The author finds considerable injury from fumes 

 of coke ovens within a radius of a kilometer, extent of inj ury varying with distance from ovens, 

 direction from ovens, intervening barriers, etc. Different plants vary greatly with regard to 

 their susceptibility to injury — legumes, roses, and potatoes suffering more than other crops. 

 The character of the injury is very different from that of the acid injuries produced by sulphur 

 fumes, and the writer does not believe that sulphur is responsible in this case. He indicates 

 rather that some basic compounds of the anthracene-oil fraction and possibly ammonia are 

 the toxic substances, although this phase needs further investigation. No method of preven- 

 tion has been found. — P. J. Anderson. 



ELECTRICITY AND MECHANICAL AGENTS 



531. Peck, J. L. Les differences de potential en biologie. [Differences of potential in 

 biology.] Compt. Rend. Soc. Biol. 83 : 2S2-2S3. 1920.— A growing carrot plant removed from 

 the soil and placed with its roots in water up to the middle showed a difference in potential 

 between leaves and water of about 4 volts. Under the influence of ultra-violet rays this in- 

 creased to 8 volts and became zero on adding to the water 10 drops of HNO3 per 100 gm. water. 

 Further experiments with animal tissues showed a difference in potential between muscles 

 and blood, or between muscles and water, into which they were placed. These were increased 

 by ultra-violet light or some toxins. The absorption of water by the muscles shows a close 

 relation to the potential differences between the water and muscle. — E. A. Bessey. 



SOIL SCIENCE 



J. J. Skinner, Editor 

 F. M. Schertz, Assistant Editor 



(See also in this issue Entries 11, 25, 27, 32, 34, 57, 100, 107, 112, 203, 208, 402, 437, 452, 480, 



574) 



532. Aiyer, a. R. Padmanabha, and D. V. Bal. The chemical and biological aspect of 

 Bhata soil of Chandkhuri experimental farm, Central Provinces. Agric. Jour. India 15: 644- 

 649. PL 46-50. 1920. — The Bhata or lateritic soils of Central Provinces were found to be 

 poor on account of the large per cent of coarse material they contained and to a lack of phos- 

 phorus. The addition of phosphorus improved the soil for the growth of leguminous Tops. 

 The soil has good ammonifying and nitrifying powers. When cake was applied and inoculated 

 with emulsion of a rich black cotton soil, good growth was secured. — /. /. Skinner. 



533. Albrecht, W. A. Bat guano and its fertilizing value. Missouri Agric. Exp. Sta. 

 Bull. 180. 15 p. 1921. — Chemical analyses of bat guano and pot and field experiments with 

 this material as a fertilizer are reported. The material, which is commonly found in caves 

 in Missouri, is said to have considerable value as a fertilizer, its nitrogen content varying from 

 0.31 to 10.44 per cent, phosphoric acid 2.5 to 7.9 per cent, and potash 0.36 to 1.9 per cent. In 

 ammonification tests fresh bat guano produced as much ammonia and more nitrates than 



