AGRICULTURAL BOTANY. 521 



readily than the potash of feldspar. From 10.37 to 14.67 per cent of the potash 

 of biotite was assimilated, as compared with from 1.66 to 2.86 per ceut of the 

 potash of the muscovite. 



Preparation of superphosphate with sulphur dioxid and chlorin, Q. Ses- 

 TiNi (Indus. C'him., 12 {1912), pp. 49-,53; abs. in Jour. Soc. Chein. Indus., 31 

 (1912), No. 6, p. 293). — Experiments are reported which showed that it is pos- 

 sible to prepare superphosphate by the combined action of sulphur dioxid and 

 chloriu on crude mineral phosphate according to the following equation : 



Ca8(P04)2+2S02+4H.O+2Cl2=Ca(H.P04)=+2CaS04+4HCl. 



Guano supply of French Somaliland, W. A. Schulz {Daily Cons, and Trade 

 Rpts. [U. 8.], 15 {1912), No. 162, p. 1S9).— It is stated that the abundant sup- 

 plies of guano on the numerous small islands along the coast of French and 

 Italian possessions in the Red Sea are beginning to be exploited, recent ship- 

 ments having been made to Antwerp and Suez through the port of Jibuti The 

 guano is stated to be of high quality. 



Fertilizer from city refuse {Municipal Jour, and Engin., SO {1911), Nos. 19, 

 p. 678, figs. 2; 26, p. 91S). — A machine which has been in operation at South- 

 wark, England, for grinding garbage and preparing a fertilizer suitable for use 

 on stiff clay soils is described. 



The utilization of sewage sludge {Engin. Rec, 65 {1912), No. 26, pp. 101, 

 702). — The practicability of the use of sewage sludge as fertilizer is questioned, 

 as is also the economy of extracting grease from the material, although the 

 latter process increases the value of the sludge for fertilizing purposes. The 

 authorities cited are G. W. Fuller (E. S. R., 27, p. 212) and \V. Naylor (E. S. 

 R., 27, p. 318). 



Annual report on fertilizers August 1, 1911, B. B. Ross {Ann. Rpt. Ala. 

 Dept. Agr. and Indus., 1911, pp. 163-316). — ^Analyses and valuations of fertil- 

 izers inspected in Alabama are reported, with the text of the state fertilizer 

 laws and a brief discussion of the nature and use of fertilizers. 



Analyses of commercial fertilizers, M. A. Scovell and II. E. Curtis (Ken- 

 tucky Sta. Bui. 158, pp. 197-328). — This bulletin reports analyses and valua- 

 tions of fertilizers inspected by the Kentucky Station during 1911. The re- 

 sults show " that in most cases the samples analyzed have come fully up to the 

 guaranty or, where there is a slight deficiency in one ingredient, it has been 

 made up by an excess in one or both of the other ingredients." 



Eussian fertilizer situation (Amer. Pert., 37 (1912), No. 1, pp. 38, 39). — 

 Figures are given which show that the amount of fertilizer used in Russia 

 nearly trebled in the 5 years 1907 to 1911, being in the latter year 360,000 

 short tons. The use of fertilizers in the Empire is, however, still comparatively 

 small. The fertilizers used are practically all imported, although considerable 

 quantities of bones, fish waste, slaughterhouse by-products, and similar mate- 

 rials are exported. Large deposits of phosphates are available. 



AGRICULTURAL BOTANY. 



Chemical effects of radiant energy in plant processes, H. A. Spoehb (Car- 

 negie Inst. Washington Year Book, 10 (1911), p. 65). — Experiments in photo- 

 chemical reactions supposedly simUar to those occurring in plants have been 

 carried out. 



It was found that aqueoais solutions of potassium and calcium nitrates are 

 reduced by means of ultraviolet light, sunlight, and diffused light to the corre- 

 sponding nitrites and ammonia, with the liberation of oxygen and the produc- 

 tion of alkalinity in the solution. It is claimed that Schimper has shown that 

 the disappearance of nitrates in the leaf takes place in the sunlight. If, there- 



