1014 EXPERIMENT STATION RECORD, 



that, where filter material is cheap and of the right quality, sand filtration of 

 both water and sewage is entirely feasible and perhaps the cheapest way. Local 

 conditions always govern, and what might do in one place would possibly be 

 wrong in another." 



On the utilization of peat for the purification of sewage, A. Muntz and 

 E. Laine (Vompt. Rend. Acad. Sci. [Paris], I'/G {IDOS), xVo. 2, pp. 53-58; abs. 

 ill Her. Sci. [Paris], 5. ser., 9 (1908), No. //, /). 123). — The authors report results 

 of experiments in which they utilized in the purification of sewage waters the 

 high nitrifying power of peat. 



The apparatus used consisted of a bed of fragments of peat 1.6 meters in 

 depth. It was found that such a filter bed was able to purify in a very satis- 

 factory manner sewage added at the rate of 4 cubic meters per square meter 

 of surface. It was also found that after excessive additions of sewage water 

 the purifying power of the peat bed was very quickly renewed, so that in the 

 case of such beds there may be wide variations in the amount of sewage added 

 without notable variation in the purification. Only a part of the ammoniacal 

 and organic nitrogen which disappeared in these experiments was recovered in 

 the form of nitric nitrogen. The authors conclude, therefore, that the oxidizing 

 action is not due exclusively to nitrifying organisms. 



SOILS— FERTILIZERS. 



Soils, T. Dietrich, L. Frank, and M. P. Neumann (Jahrcsbcr. Afjr. Chem., 

 3. sci:, 9 (1906), pp. 42-118). — This section of this rejwrt reviews as usual in- 

 vestigations (up to the end of 1906) on rocl<s and minerals and their decomposi- 

 tion products, cultivated soils, including their analyses and properties, physics, 

 especially absorption of soils, the lower organisms of soils, and moor soils and 

 moor culture. A classified bibliography is given at the end of the chapter. 



The distribution of solute between water and soil, F. K. Cameron and 

 H. E. Patten (Jour. Phys. Chetn., 11 (1907), Ao. S, pp. 581-593, figs, -i).— The 

 results obtained in studies with (1) soil, gentian violet, and water; (2) quartz 

 flour, eosine, and water; and (3) manure extract, soil, and water, are briefly 

 reported and discussed in this article, the following conclusions being reached: 



"(1) The distribution of solute between solvent and absorbent presents, in 

 general, the same characteristics with soils as with other absorbents. 



"(2) For any series of soils or other absorbents the order of the absorptive 

 capacities for one solute may be entirely different from the order for another 

 solute. 



"(3) The distribution of a solute between solvent and absorbent appears to 

 be rei)resented by the formula C"/C^=K, where ii may be loss than, equal to, 

 or greater than unity. Generally, when soils are the absorbents, the change of 

 surface or ' flocculation ' introduces a modifying factor and the form of the 

 distribution equation becomes more complex." 



Soils [of north-central Wisconsin], S. Weidman (Wis. Gcol. and Nat. Hist. 

 Survcij Bui. 16, 1907, Set. Scr. ',, pp. 672-681). — This is a brief general account 

 of the soil conditions of this area which have been more fully reported upon 

 elsewhere (E. S. R., 16, p. 27). 



Soils, B. C. AsTON (Ncio Zeal. Dept. Agr. Ann. Rpt., 15 (1907), pp. 105-110, 

 pis. 2). — Chemical examinations of a number of samples of soil from different 

 Iiarts of Xew Zealand are reported, and the results of tests of Murray's long- 

 tube sedimentation process for the mechanical analysis of soils (E. S. P., 17, 

 p. 1040) are given. The process is considered esiiecially suited for use iu schools 

 to demonstrate the difference in mechanical composition of soils. 



