SOILS FERTILIZERS. 315 



more, the distribution of the soluble constituents is unlike in the different 

 horizons as we go down in the soil. — p. fireman. 



Variability of the concentration of the soil solution and of the content 

 of the soil of easily soluble compounds in dependence on external conditions, 

 K. K. (tEdroitz (Zlitir. Opiiifii. Aiiioii. [Russ. Jour. E.rpt. Landw.], 7 (lOOG), 

 \o. .7, pp. 5.21-561). — On the basis > of theoretical considerations the author 

 arrives at the conclusion that the total concentration of the soil solution and 

 the concentration of individual compounds therein have no constant values, but 

 undergo rapid changes. This conclusion he corroborates by a survey of the 

 literature and by his own experiments. lie finds the fluctuations even during 

 short periods of time so great that it is impossible to consider the results 

 obtained by the estimation in a soil sample of the water-soluble compounds and 

 of the phosphoric acid soluble in acetic and citric acids at a given moment as 

 indicative of the character of the soil.^p. fireman. 



Investigations on weathering processes, K. D. Glinka (Pochvovyechjenie 

 [PedoIo(/ie], 6 {190J,), pp. 293-322; 7 {1905), pp. 35-62; abs. in Zhur. Opaitn. 

 Agron. [Russ. Jour. Expt. Landic], 7 {1906), No. 6, p. 677).— By a careful 

 study of the weathering processes the author aims to clear up in detail the 

 course of decomposition mainly of the aluminum silicates under various }iatural 

 conditions, and to determine the character of the decomposition of these silicates 

 when transformed into chernozem, laterite, red earth, podzol, brown laminated- 

 columnar clay. etc. — p. fireman. 



Humus-carbonate soils, and their transition into podzols (Bleisand), A. F. 

 Lebedev {Zhur. Ojmitn. Agron. [Riiss. Jour. Expt. Lmuhv.], 7 {1906), No. 5, pp. 

 571-592). — The author distinguishes, first, a type of soils rich in humus, calcium 

 carbonate, and other calcium salts (huniic salts), in the upper horizon, but poor 

 in sesquioxids and magnesia. The accumulation of silica in the upper horizon 

 is also characteristic. Second, a type of transition of the humus-carbonate 

 soils to the podzols, which is characterized by a complete leaching out of cal- 

 cium carbonate, small humus content, an impoverishment in sesquioxids, alka- 

 line earths, and alkalis, and an enrichment in silica. Considerable quantities 

 of sesciuioxids, alkaline earths, and alkalis are. however, found in the second 

 horizon which forms the transition to the parent rock. — p. fireman. 



The geological-agronomic charting of the North German flat lands, F. 

 Wahnschaffe {Deut. Eandw. Presse, SJ^ {1907), No. 4S, pp. 399, 1,00).— The 

 agricultural features of the surveys which have been made by the Royal Prus- 

 sian Geological Institute since 1873 are described. The charts prepared from 

 these surveys show properties of the soil and the nature of the subsoil so far 

 as it bears upon the question of the cultivation of the soil. 



Soils from the Mattagami region of Canada, A. Henderson {Rpt. [Ontario] 

 Bur. Mines, 15 {1906). pt. 1. pp. 151-155, fl(j. 2). — Chemical analyses of 10 

 samples, and physical analyses of 24 samples of soil from this region are 

 briefly reported. Somewhat less than half of its soils were clays and heavy 

 clays. The percentage of phosphoric acid was very uniform, while that of 

 potash varied with the amount of aluminum present, and the nitrogen content 

 was very variable. The results in general indicate that all of the soils would 

 be comparatively easy of cultivation and show that they contain a sufficient 

 quantity of fertilizing constituents to render them quite fertile. 



The story of the soil, II. S. Williams {Appleton's, 9 {1907), No. 6, pp. 72.',- 

 733). — A popular article. 



The maintenance of fertility, C. E. Tiiorne {Ohio Htu. Bui. 182, pp. 131-19/,, 

 pis. 5, fiijti. 7). — This bulletin brings up to date the account of the investigations 

 on maintenance of soil fertility which were last fully reported on in Bulletin 110 

 of the station (E. S. R., 12, p. 127). 



