804 EXPERIMENT STATION RECORD. [Vol.40 



raisins, currants, and tomatoes are said to constitute an excellent feeding stuff 

 for live stock. 



Technical handbook of oils, fats, and waxes, P. J. Fetes and F. E. Weston 

 (Cambridge, Eng.: Univ. Press, 1918, vol. 1, 2. ed., pp. X+2S0, pis. -}2, figs. 33). — 

 This is the second edition of the volume previously noted ( K. S. it., 39, p. S). 



Technical handbook of oils, fats, and waxes, P. J. Fryer and F. E. WE8TOH 

 (Cambridge, Eng.: Univ. Press, 1918, vol. 2, pp. XVI +314, pi. 1, figs. 63).— This 

 companion volume to the one noted above deals with the practical examination 

 and analysis of the natural and hydrocarbon oils, fats, and waxes. After pre- 

 liminary sections on an introduction to practical work for technical students 

 and directions for sampling and preliminary tests, the subject matter is pre- 

 sented in the following sections: Practical methods for the standard analytical 

 determinations; specific tests for oils, fats, and waxes; Identification and deter- 

 mination of fatty acids and alcohols (including glycerin) ; testing and analysis 

 of hydrocarbon oils and waxes; testing and analysis of rosin and turpentine; in- 

 terpretation of results; and a scheme for the identification of an oil. fat, or 

 wax. A supplementary section contains the necessary tables lor use in the 

 determinations described, and appendixes in which are described the turbidity 

 test for oils and fats, previously noted from another source (K. S. R., 39, p. 

 110), and two methods for the determination of the small amounts of glycerin 

 in hard soaps and in soft soaps made from fatty acids. 



The more important operations are illustrated by means of photographs 

 showing the methods of working and details of the apparatus. 



Pectin studies. I-II, S. Oi»kn Uulcrnnt. Ztschr. Phys. Chan. Biol, 3 (1917). 

 No. 2, pp. 11-93, fig. 1; abs. in ('lam. Ah*., 11 (1917), No. ftl, p. 9923).— Two 

 papers are presented : 



I. Pectin substances ass acids (pp. 71 -S2). — By means of a method depending 

 upon slight changes in electrical conductivity which occur on the addition of a 

 small amount Of ammonium hydroxid to an aqueous suspension of plant tissues 

 previously freed from electrolytes by centrlfugallsation, the author has demon- 

 strated the presence in plants of nearly insoluble acid substances which on treat- 

 ment of these ammonium salts with dilute acids yield gelatinous substances of 

 the nature of pectin. These pectin substances, in addition to acting as the 

 binding material of the plant tissues, are considered to constitute a means for 

 regulating the content of H- and OH-ions in the circulating fluids in the tissues 

 and maintaining the cell contents in a slightly acid condition. 



II. Ah/ic and fucic acid* (pp. S.'i-93). — Algic and fucic acids treated by the 

 method noted above were shown to be true acids. From its elementary 

 analysis, molecular weight, and properties, fucic acid is considered to be a 

 dipentose-dicarboxylic acid. 



A study of the cyanogenesls in Sorghum vulgare, C. T. Dowki.i. (Oklahoma 

 Sta. nui. 122 (1919), pp. 8; Jour. Ayr. Research [U. 8.1, 16 (1919), No. ?. pp. 

 175-181). — The results are reported of an investigation of cyanogenesls in dry 

 and fresh sorghum under various conditions. The method employed for de- 

 termining the hydrocyanic acid was a modification of that used by Viehoever 

 and Johns (E. S. P., 34, p. 11) and that of Knight (E, S. R .. 33, p. 15), the 

 sorghum being digested with water distilled into sodium hydroxid, the dis- 

 tillate evaporated on an electric hot plate, and the hydrocyanic acid converted 

 into Prussian bine and determined gravimet ideally. 



Drying of the sorghum was found to remove approximately three-fourths of 

 the hydrocyanic acid, the rapidity of drying determining the percentage of 

 acid retained by the sorghum. This Is considered of Importance on account of 

 the fact that in dry seasons the sorghum is often cut after it has been par- 



