AGRICULTURAL CHEMISTRY AGROTECHNY. 611 



tube which allows the gradual addition of the alkali solution without loss, 

 and a means of connecting; the apimratus with the suction pumj) to in-event 

 buuipinj;. 



Some remarks about the determination of the total nitrogen by Mitscher- 



lich's method, V. Schknkk {Clinii. '/Jq., .33 (t'JO!)), No. 78, pi>. 712, 71,i). 



\Vith reference to the claim of Mitscherlich and others that up to the time 

 that the .Mitscherlich method (E. S. K., 21, p. 2()S) was described no accurate 

 method existed for the deti'rminat ion of nitro>;en in small amounts, the author 

 states that he i»ul)lished a method in 1S!)G ( E. S. 11., S, ]>. 741) which meets 

 the ri'ciuirements. 



Estimation of phosphoric acid in ashes, W. PLiiCKKK (ZtHchr. UnterKUch. 

 \(ilir. II. GenufifimtL, 17 {1909), So. S, pp. .'i/i6-.'i').'i : iilis. in Jour. Clicin. Sor. 

 [Lomlon], 96 (1909), No. r,GO, II, p. 5/8).— The results obtained by von 

 Lorenz's method (E. S. K., i:>, ji. 14) were found reliable. Iron, aluminum, 

 jind silica did not intiueuce the results. 



Determination of phosphoric acid (gravimetric molybdate method for the 

 international trade of raw phosphates) {(Jhein. News, 100 [1909), No. 2588, p. 

 1). — A full description of the mode of analysis of raw phosphates i)roposed at 

 the Internationa] Congress of Applied Chemistry. 



Fuchsin S as a standard solution for the estimation of nitrites in water, 

 J. H. Kastle and E. Elvove {Ahs. hi Clicni. Zty., 33 (1909), No. 69, pp. 626, 

 627). — The instability of the iodin-chloroform solutions employed for the 

 estimation of nitrites in water led the authors to look for a more stable reagent. 

 Fuchsin S acidified with hydrochloric acid was found to possess nearly the 

 same color and numerous tests gave favorable results. 



Polarization and saccharimetry, D. Sidersky (Polaiisation ct Haccharimv- 

 trk: Paris \190S], 2. vd., rcr. and enh, pp. 168, figs. J/O). — This is a manual 

 on polarization and saccharimetry. The initial chapter.s of the book consider 

 the physics of polarization and polarized light and the various kinds of in- 

 struments in use for polariscopy. The succeeding chapters are devoted to the 

 determination of sugars, alkaloids, ter])enes, sugar in urine, and resin in oils. 



The details of a modified method for the hydrochloric acid extraction 

 process in the polarimetric determination of starch, Thorne and Jeffens 

 (.4^.s-. ia CJicni. Ztij., 33 (190!)). Xo. 09. p. (]2'i).—\ modification of the Effront- 

 Ost-Lintner method is suggested. 



In this method 5 gm. of the material ground as fine as possible is rubbed up in 

 a mortar with water until the mass ceases to cling to the side of the vessel, 20 

 cc. of water being generally required. About 40 cc. of hydrochloric acid of 

 sjiecific gravity 1.15 is added, amid constant stirring, luitil the mass swells and 

 forms a viscous fluid. The mixture is allowed to stand for 10 minutes and 

 then transferred to a 200 cc. flask, containing 10 cc. of a 4 per cent pliosi»ho- 

 tnng.stic acid and 20 cc. of hydrochloric acid. Th(> mortar is washed out with 

 dilute hydrochloric acid and the flask filled therewith to the 200 cc. mark. 

 The flask is then shaken, the contents transferred to a wide-mouthed bottle, 

 and the whole well shaken initil a definite flocculent precipitate is obtained and 

 the supernatant fluid is i)ractically clear. The solution after filtration is 

 ready for i)olarization. If the 200 mm. tube of the Schmidt-IIaensch scale 

 is employed with white light the ijercentage of starch is calculated by the 



formula P=^ ^ The concentration of starch in this method iu>ver runs 



11.6 



over specific gravity 1.1. 



The determination of mannose, arabinose, xylose, and hydrolized milk 



sugar, K. O. IIerzog and F. Horth (Ztschr. Physiol. Chem., 60 (1909), No. 2, 



pp. tr)2-l ')-',; (lbs. in Clirm. Znithl.. 1909, U, No. 1. pp. 67, 6'.S).— Thirty cc. of 



