1018 EXPERIMENT STATION RECORD. 



"The double application of carbon bisulpbid showed, two uionths later, the 

 following effect on the soil : 



"(1) Ammouiflcation had evidently been retarded at first, but subsequently 

 became more intense, not sufficiently so, however, to equal the effect of the 

 other treatments. (2) Nitrification was more intense than in the imtreated 

 soil. (.3) Denitrification was much less prominent than in the untreated soil, 

 (4) Nitrogen fixation was markedly superior to that in the untreated soil. 



" The treatment with acid phosphate led to a conipai'atively largo increase in 

 animonification ; a comparatively small increase in nitrification; a decrease in 

 denitrification, and a decrease in uitrogen fixation. 



" The treatment with acid phosphate and single quantity of carbon bisulpbid 

 led to a marked increase in ammonification ; an increase in nitrification; a small 

 decrease in denitrification ; a decrease in nitrogen fixation. 



"Muriate of potash led to a decrease in ammonification; increase in nitrifica- 

 tion : slight decrease in denitrification ; slight decrease in nitrogen fixation. 



" When used in combination with the single quantity of carbon bisulpbid, 

 muriate of potash led to an increase in ammonification; increase in nitrifica- 

 tion; decrease in denitrification; increase in nitrogen fixation. 



" The lime treatment led to a pronounced gain in ammonification ; a gain in 

 nitrification ; a decrease in denitrification ; and an increase in nitrogen fixation." 



Ammoniflcation in culture solutions as affected hy soil treatment (pp. ISG- 

 204). — The effect of applications of calcium and magnesium carbonate alone and 

 in combination, acid phosphate, Thomas slag, bone meal, sodium nitrate, cal- 

 cium nitrate, calcium cyanamld, ammonium suli)hate, cyanate (a by-product in 

 the manufacture of illuminating gas), and dried blood was studied in pot and 

 culture experiments. 



The results of the experiments with calcium and magnesium carbonates have 

 already been reported in detail (E, S. R., 19, p. 828). 



The effect of applying acid phosphate, as measured by the culture experi- 

 ments, was irregular and inconclusive. Thomas slag, on the other hand, in- 

 creased the production of ammonia to a considerable extent. Nitrate of soda 

 in the larger amounts (5 gm. per pot) increased the ammonification coefficient, 

 while anniionium sulphate depressed it. Dried blood greatly increased the 

 ammonifying power of the soil, and calcium cyanamid at first increased and 

 later depressed it. Cyanate was distinctly injurious to the ammonification bac- 

 teria in the soil. 



In pot experiments with millet the cyanate depressed the yield of dry matter 

 and particularly of nitrogen. Nitrification was apparently slightly stimulated 

 by the larger applications of nitrate of soda. Ammonium sulphate also slightly 

 favored nitrification. The effect of dried blood on nitrification was not clearly 

 shown. The cyanamid and cyanate were unmistakably injurious to the nitri- 

 fying bacteria. 



On the influence of bacteria on the conductive capacity of soils for heat, 

 R. Stigell (Ccntbl. Bakt. [etc.], 2. Aht., J!) {1H07), Xo. 16-J8, pp. .',90-502).— 

 Observations on soils inoculated with cultures of Bacillus suhtilis, B. coli com- 

 munis, B. mesentericus fuscus, and Proteus vulgaris, and subjected to alternat- 

 ing higher and lower temperatures, are reported. While the differences in tem- 

 perature conditions of inoculated and uninoculated soil similarly treated were 

 small, the conclusion was reached that bacteria, at least under the most favor- 

 able conditions for development, retard the conduction of heat in soils and 

 thereby reduce the temperature changes due to variations in the outside 

 temperature. 



