610 EXPERIMENT STATION RECORD. 



trate in a siiJpburic acid solution in the presence of copper sulphate at a copiier 

 cathode. Very comprehensive analytical data were obtained for the solution 

 and for the gases at the anode and cathode at a number of intervals during 

 electrolysis. 



The authors conclude that ammonium sulphate in a sulphuric acid solution 

 is oxidized at a platinum anode, nitrogen gas being liberated; that hydroxyla- 

 min is found as an intermediate step to ammonia in the electrolysis of nitrate 

 in sulphuric acid with copper sulphate; that nitrogen is liberated at the cathode 

 and at the platinum anode; and that nitrogen undergoing either oxidation or 

 reduction probably goes through the several intermediate stages, if not all, 

 which exist between the initial and final state of oxidation. They have defined 

 the electrical, chemical, and physical conditions under which these changes 

 take place. 



In the third paper, the authors study particularly the reduction of hy- 

 droxylamin in a sulphuric acid solution at a copper cathode with copper sul- 

 phate present, and the oxidation of hydroxylamin at a platinum anode. The 

 conditions of the experiments and single ix»tential discharge measurements 

 are given. 



It was found that hydroxylamin may be reduced to ammonia ; that nitrogen 

 is liberated at both the anode and cathode, at the anode at a fairly constant 

 rate, ammonia being left in solution, and at the cathode rapidly at first and 

 in such quantity as to suggest the formation of hydrazin as an intermediate 

 step and its subsequent oxidation to hydroxylamin, then giving free nitrogen 

 and as electrolysis proceeds the yield of free nitrogen decreasing. The same 

 high initial evolution of nitrogen is met in the electrolysis of nitrate under the 

 same conditions, and suggests that here, too, the hydroxylamin formed may be 

 reduced to a lower stage of oxidation, such as liydrazin. 



The complexity of the humus extract of soils, E. C. Shorey {Abs. in Science, 

 n. scr., 31 {1910), 'So. 807, p. 960). — "A summary of the work of the Division 

 of Fertility Investigations of the Bureau of Soils on soil organic matter. The 

 author announced the isolation by him of 23 organic compounds from soils. 

 Seventeen of these have been identified and 8 types of compounds are repre- 

 sented." 



The availability of soil phosphates, W. P. Kelley (Jour. Indus, and EngUi. 

 Clicm., .2 (1910), A'o. 6, pp. 277-2S0). — From Hawaiian soils the author was 

 able to show that the neutralization coefficient obtained with fifth-normal 

 nitric and hydrochloric acid bore a direct relation to the availability of the 

 soil phosphates. He further investigated Hawaiian air-dry soils containing 

 large amounts of iron and alumina in combination with large amounts of 

 phosphates (in which combination they would not be readily available for 

 plant growth), with particular regard to the solubility of the phosphates in 

 fifth-normal hydrochloric acid and 1 per cent sodium hydrate. The results 

 show that the fifth-normal hydrochloric acid is of value in determining the 

 phosphate deficiencies in soils of very different types, but that the strength 

 of acid generally employed is not sufficient for highly ferruginous soils. 



A method of determining' the cellulose-decomposing power of the soil, H. R. 

 Christensen {Tidsskr. Landbr. Plantcavl, 17 (1910), Xo. 2, pp. 356-359).— The 

 sample to be examined, corresponding to 50 gm. of dried soil, is placed in a 

 300 cc. Erlenmeyer flask so that it loosely covers about three-fourths of the 

 bottom. Distilled water is now carefully added with a pipette until the soil 

 is nearly saturated. Two small pieces of ash-free filter paper, 30 mm. long and 

 5 mm. wide, are next placed in the fiask and pressed down with a glass rod so 

 as to touch the soil. According to the author's experience with about 50 dif- 

 ferent soil samples, after a period varying from a few days to several weeks 



