712 EXPERIMENT STATION EECOED. 



1, pp. XXXI^538, fiijs. 63; 2, pp. Xyi+539-1125, figs. JJ).— This is volume 3, 

 parts 1 and 2, of tlie work previously noted (E. S. R., 27, p. 609). Among the 

 subjects considered are mineral oils ; lubricants ; oils, fats, and waxes ; 

 ^special methods of analysis employed in the oil and fat industries; resins, 

 balsams, and gum resins; drugs and Galenical preparations; essential oils; 

 tartaric acid ; citric acid ; organic preparations ; India rubber and rubber 

 goods; vegetable tanning materials; leather; ink; sugar; starch and dextrin; 

 alcohol, potable spirits, and liqueurs; vinegar; wine; brewing mjjterials and 

 beer ; paper ; textile fibers ; and inorganic colors. 



The application of the paper pulp filter to the quantitative estimation of 

 calcium and magnesium, S. L. Jodidi and E, H. Kellogg (Jour. Franklin In^t., 

 181 {1916), No. 2, pp. 217-232, fig. 1). — From their investigations the authors con- 

 clude that the use of the paper pulp filter is superior to ordinary paper filtra- 

 tion, both in point of time and ease of manipulation. Experimental data in- 

 dicate that as great accuracy is possible with the pulp filter as with stand- 

 ard filter paper. 



Differential iodimetry. — I, Determination of periodates, iodates, bromates, 

 and chlorates in the presence of each, other, O. L. B.venebey (Jour. Amcr. 

 Chcni. Soc, 38 (1916), Xo. 2, pp. 330-SJtl, figs. 2).— As a result of his studies the 

 author has found that "(1) certain oxidizing agents can be determined in the 

 presence of each other iodimetrically in a differential manner by regulation of 

 the concentration of reagents, especially the acidity, the temperature, and the 

 time of reaction. (2) Periodate reacts completely with iodid in saturatetl boric 

 acid solution containing sufficient borax to diminish the acidity to a slight 

 extent, forming iodate and free iodin. (3) lodate is acted on by tenth-normal 

 iodid in fourth-normal acetic acid solution and the free iodin can be titrated. 

 (4) In fifth-normal hydrochloric acid solution containing tenth-normal iodid, 

 bromate is completely decomposed and the free iodin can be titrated. (5) 

 Sixth-normal hydrochloric acid acting in presence of tenth- to fifth-normal 

 iodid decomposes chlorate completely. Mter rendering the solution alkaline 

 and then acidifying, the iodin can be titrated with thiosulphate. (6) By com- 

 bination of (2), (3), (4), and (5), periodate, iodate, bromate, and chlorate 

 can be determined differentially in the presence of each other and in the pres- 

 ence of perchlorate." 



A simple hydrogen electrode, 11. P. Babendbecht (Biochcm. Jour., 9 (1915), 

 Xo. 1, pp. 66-70, figs. 2). — The author describes a simple arrangement for the 

 determination of the true reaction of liquids as an improvement on the electro- 

 metric titrating apparatus described by Walpole." Insiaiitancuus and accurate 

 estimations can be made in liquids which contain carbonic acid and oxj-gen. 



A method for the estimation of hygroscopic moisture in soils, W. D. Haigii 

 (Sci. Proc. Roy. Dublin Soc, n. ser., 14 (1915), Xo. 40, pp. 529-53Jf, fig. 1). — A 

 method for determining the hygroscopic moisture in soils is described, which is 

 based on the desiccating effect of calcium carbid. An apparatus is used in 

 which the soil and an excess of calcium carbid are mixed, and the acetylene 

 gas evolved, as a result of the calcium carbid taking up the soil moisture, 

 serves as a measure of the hygroscopic water in the soil. 



Comparative tests of this method witli the ordinary method of heating in the 

 water oven, using six arable soils and a sand and a peat soil, showed that while 

 the results obtained by both methods agreed quite closely, the amount of water 

 Indicated by the carbid method was always slightly lower than that indicated 

 by heating in the oven. The difference increased in a rough proportion to the 



"Biochem. Jour., 7 (1913), No. 4, pp. 410-428. 



