220 EXPERIMENT STATION RECOED. 



It was observed that the actiou of the sulplaiirous acid depended very largely 

 upon the amount and character of the soil bases. When the soil was given an 

 acid reaction as a result of the addition of the sulphurous acid the growth of 

 the plants was retarded, but when the soil contained a sufficient amount of 

 bases to neutralize it no injurious effect was observed. A high content of cal- 

 cium carbonate reduced the solvent power of the sulphurous acid on copper 

 compounds and thus diminished the injurious effect resulting from this cause. 



Contribution to the knowledge of humus compounds, 1{. Miklauz (Ztschr. 

 Moorkultur a. Turfvcrwcrt., h (IDOS), pp. 285-S27 ; ahs. in Ztschr. Angew. Chcm., 

 22 {1909), No. 16, pp. 7.39, 77,0; Chem. Zenthl., 1909, I, No. 11, pp. 937, 938).— 

 The results of a study of the action of acids and alkali solutions on jieat and 

 do])plerite and of the products of solution are reported. 



The catalase of soils, I). W. May and P. L. Gile {Porto Rico -S7«. Circ. 9, 

 pp. 3-13). — The occurrence of catalase in various vegetable substances and in 

 soils w^as investigated by Loew and May several years ago (E. S. R., 13, p. 11.5). 

 Investigations by Konig et al. (E, S. R., 17, p. 1138) indicate that the evolution 

 of oxygen on treating soils with hydrogen peroxid is dne to catalase produced 

 by soil bacteria. Pursuing this line of investigation further the authors con- 

 clude that " the power of a soil for decomposing hydrogen peroxid depends 

 upon the catalase content, enhanced in special cases only by the colloidal actiou 

 of the mineral constituents. 



"This property is not a measure simply of the bacterial content, but is a 

 rough measure of the combined quantity of bacteria and organic matter present 

 in the soil. 



" The most accurate method of comparing different quantities of catalase is 

 on the basis of the time required to evolve a certain volume of oxygen from a 

 certain quantity and concentration of peroxid. 



" The speed of the reaction between catalase and hydrogen peroxid is depend- 

 ent upon: (1) The amount of catalase present; (2) the concentration of the 

 peroxid used; (3) the amount of peroxid used; (4) the acidity or alkalinity 

 of the solution in which the reaction takes place; (.5) the temi)e.rature at which 

 the reaction takes place; and ((>) the frequency with which the tiask contain- 

 ing the catalase and peroxid is agitated. 



" In the method adopted the catalase contents were compared on the basis 

 of the number of minutes required by 5 gm. of soil to evolve 100 cc. of oxygen 

 from 60 cc. of neutral 0.92 per cent peroxid, the flask being shaken continually 

 during the reaction. 



" Exposure to a high temperatui-e for a short time had less eftect in destroy- 

 ing catalase in soils than the action of a lower temperature for a longer time. 



" Carbon bisulphid inhibits materially the catalytic action. 



" Treatment of soil with manures was without effect on the activity or amount 

 of catalase." 



Increasing- the soil's nitrogen content {Sci. Aiiirr. Sup., 67 {1909), No. 17^0, 

 pp. 296, 297, flgn. 8). — This is a brief account of investigations by Bottomley 

 on seed and soil inoculation for leguminous and nonlegumuious croi)s. 



Inoculation with nodule-forming' bacteria, W. S. Sayer {Michigan 8ta. 

 Circ. 5, pp. .'/, figs. 3). — This circular explains briefly the value, need, and 

 method of inoculation with nodule-forming bacteria. 



General fertilizer experiments, T. F. Hunt {Pcnnsitlrania Sta. Rpt. 1908, 

 pp. 68-93. pis. 8). — This is substantially a reprint of Bulletin 90 of the station 

 (E. S. R., 20. p. 1017), but giving more detailed data. See also a previous note 

 (E. S. R., 15, p. 143). 



Action of fertilizers on woody plants, Ciiancerel {Bui. Soc. Nat. Agr. 

 France, 69 {1909), No. 3, pp. 235-2-'il). — Experiments in water cultures and 



