AGRICULTURAL CHEMISTRY. 409 



Determination of nitric acid in the soil, S. Frankfurt and A. Dushechkin 

 i]'ii<-stiiik Sahli. Piomuinh., JD06, Xo. .'I'f, ijp. (jo^-660 ; abs. in Zhur. Opuitii. 

 Af/roii. \lii(s.s. .lour. Expt. Landw.], S (1907), No. 2, />. 250; Chem. Ahs., 1 

 (1907), \(). 17, I). 2285). — The conchisious of the authors are as follows: (1) 

 The hitherto accepted method of determining nitric acid in soils by digesting 

 tile soil with water during 4S Lours gives results considerably too low; (2) two- 

 hour digestion is sufficieut to extract the nitric acid from the soil. Longer con- 

 tact of water with the soil renders the use of chloroform or other similar agent 

 necessary. — p. fireman. 

 • The obtaining of the soil solution in unaltered condition, V. Ischebekov 

 (Zhur. Oiniitit. Ayntn. [Nu-ss. Jour. Expt. Landir.l, S (1907), Xo. 2, pp. 

 I'i7-166). — The method proposed consists in the disi)lacement of the aqueous 

 soil solution by another liquid, such as ethyl or methyl alcohol. The soil is 

 placed in a glass tube covered at the bottom with closely woven linen and the 

 alcohol is poured over it ; after some time, the length of which depends on the 

 height of the alcohol column and the degree of saturation of the soil, the aque- 

 ous solution begins to flow out through the linen Alter. When a layer of half 

 a centimeter of alcohol was poured on a saturated soil drops of liquid began at 

 once to flow through the linen. With a layer of 10 to 15 cm. of alcohol there 

 was a steady flow of drops of the a(pieous solution. A^'ith a soil containing, 

 for example, 2-1 cc. of water, about 23 cc. of clear aqueous solution was obtained 

 before the outflowing liquid showed any turbidity indicating admixture of 

 alcohol. The aqueous solution was perfectly transparent, without any traces 

 of turbidity or precipitate, but slightly colored yellow by the humus matter. lu 

 case of soils with varying degrees of humidity, and esiiocially with sandy soils, 

 it was found necessary to pack the soil in the tube in order to prevent the 

 flowing of the alcohol through free passages. 



In experiments described by the author 100-gram samples of a sandy soil 

 received, respectively, 10 cc. and 20 cc. of water and the aqueous solution was 

 displaced by alcohol. The hygroscopic moistui'e of the soil was 0.41 per cent; 

 hence there was in one sample 10.41 cc. and in the other 20.41 cc. of water. 

 In the former case 8 cc. and in the latter 16.5 cc. of aqueous solution was 

 obtained. Seven cubic centimeters of the first solution and 10 cc. of the second 

 were evaporated and the residue dried at 105° C. The residue from the 7 cc. 

 was 0.02(>1 gm., indicating 0.0.388 gm. of dissolved substances in the 100 gm. of 

 the soil. The residue from the 10 cc. was 0.0187 gm., indicating 0.0382 gm. of 

 dissolved substances in 100 gm. of soil. Thus the addition of more water did 

 not perceptibly increase the salt content of the solution. 



In another experiment 300 gm. of a sandy soil received 53 cc. of water. The 

 outflowing solution was collected in separate portions. I'ortion 1 contained 

 15 cc, portion 2, 20 cc, and portion 3, 17 cc, the last portion being quite turbid 

 and mixed with alcohol. The entire first portion and an equal amount of the 

 second were evaporated and dried at 105° C. There were obtained, before 

 ignition, from portion 1, 0.0411 gm., and from portion 2, 0.0425 gm., and after 

 ignition, froui portion 1, 0.0080 gm., and from portion 2, O.OOS gm. In, the third 

 portion the salt content was greatly reduced by alcohol. — p. fireman. 



The interaction between minerals and water solutions with special refer- 

 ence to geolog'ic phenomena, B. C. Sullivan (U. <S,'. Geol. Survri/ Bui. 312, 

 pp. ()9). — This bulletin reports A-ork undertaken in the chemical laboratory of 

 the I'. S. Geological Survey " in an attempt to apply chemical methods to the in- 

 vestigation of geologic jn'ocesses and especially of the secondary deposition of 

 ores," accompanied by an outline of earlier work along this line on flltraticn and 

 diffusion and clieniical reaction. 



