712 EXPERIMENT STATION RECORD. 



Some features of Iowa ground waters, W. S. IIendrixson iProc. Iowa Acnd. 

 Set., 1 'f (1907), pp. /<S'7'-/9.9). — The clmracter of these waters is briefly dis- 

 cussed on the basis of chemical analyses of a number of samples from deep and 

 shallow wells. The investigations were made in cooperation with the U. S. 

 Geological Survey. 



Methods of sterilizing water by means of permanganate of potash, Ferraud 

 and O. Lamhert (Rev. Hyg. ct Pol. f^lamt.. .W (1908). No. 7, /)/). 55S-56S) .—The 

 methods of Hy and Lambert are described, and tests of their efficiency are 

 reported. The general conclusions reached are that all reactions which involve 

 the precipitation of manganese oxid in a solution of permanganate may be used 

 as bases for processes for the sterilization of water. The bactericidal action 

 is due solely to the formation of this precipitate. The authors are of the opinion 

 as the result of these and previous experiments that the bactericidal action is 

 a phenomenon of I'adio-activity. 



The Merthyr sewage farms, T. F. Harvey (Jour. Roy. Sanit. Inst., 29 (1908), 

 No. 10, pp. 6-',8~655; Surveyor, 34 (1908), No. 862, Sup., pp. i^-ifi).— The 

 methods of sewage disposal which have been in use at Merthyr since 1858 are 

 briefly described, but i)articular attention is given to the present methods of 

 disposal on two sewage farms. The sewage from a city of about 100,000 popu- 

 lation is satisfactorily disposed of on these farms by surface irrigation. 



" It may be fairly claimed that the working of the Merthyr sewage farm .... 

 has been successful, and while the stipulation that * profit is to be subservient 

 to the proper disposal of sewage ' has been strictly adhered to, the pecuniary 

 result has been satisfactory. Taking an average over the last ten years, the 

 yearly general expenditure on all the farms has been fl,914 4s. 9d. [about 

 $9,417] and the yearly revenue £2,744 17s. 4d. [about $13,312.56] showing a 

 profit over and above the working expenses of £802 12s. 7d. [about $3,892.72] 

 per annum." 



SOILS— FERTILIZERS. 



Studies on soils, A. Atterberg (Landic. Vers. Stat., 69 (1908), No. 1-2, pp. 

 93-lJ,3, figs, 2; abs. in CJietn. Ztg., 32 (1908), No. 87, Repert., p. 554; Chem. Abs., 

 3 (1909), No. 2, pp. 220, 221). — In continuation of previous investigations (E. 

 S. R., 15, p. 549) the author studied the properties and arrangement of the phy- 

 sical constituents of soils of different types. Among the topics reported upon are 

 the size and methods of separation of different soil constituents; the hygro- 

 scopicity of fine sand: the volume, air space, and capillarity of sandy soils; 

 evaporation from sands; the relation of sand to precipitation; percolation in 

 sand ; relation of sand to root hairs of plants ; the flocculation of fine sand ; 

 Browuian motion ; the rational classification of sand ; and analyses of glacial 

 and alluvial sandy soils. 



A modified classification of the sandy particles in soils is proposed. The 

 word sand is confined to the coarse sand of dry sandy soils. The fine sand of 

 better soils is termed " mo." Sand finer than 0.02 mm. in diameter is con- 

 sidered to be clay-like in properties. The word " ler " is used to designate the 

 finest sand and amorphous clayey particles. The more important capillary 

 ])roperties of the sand particles are discussed. 



The annual fluctuations of soil temperature in different climates, W. Kxjhl 

 (Dcr jdhrliche Gang dcr Bodcntcmpcratnr in vcrschicdcncn KUmaten. Iiiaug. 

 Diss., Univ. Berlin, 1907, pp. 68, dgms. 4). — Data from a number of places in 

 Europe, Asia, Australia, and Central America are compiled and analyzed, the 

 yearly fiuctuations of soil temperature with reference to air temperature being 

 illustrated in a series of diagrams. A bibliography of 47 references is given. 



