CHEMISTRY, 747 



of two waters are reported. Thene hear out Drawe's conclusion that the alkalinity 

 after hoilinar is due entirely to sodium carhonate, l)ut they also indicate that magne- 

 sium carljonate remains in solution, the latter carhonate presenting a neutral 

 reaction. 



The determination of hardness in waters, F. Auerbach (Chem. Ztg., 28 

 {1904), Xo. 2, p. 16). — Referring to a previous article hy Drawe, the author ques- 

 tions whether the permanent alkalinity is not in part at least due to magnesium 

 carboTiate as first pointed out by Pfeiffer. 



Modifications of the Pelouze-Fresenius method of determining nitric acid, 

 L. DEBoruDEAUX {Bid. ,Sor. Chim. Paris, 3. ser., 31 {1904), ^o. 1, pp. 1-3). — In the 

 modification proposed the Fresenius apparatus is used with the addition of a cooling 

 device to prevent loss of nitric acid. The air is driven from the flask containing the 

 nitrate by means of carbon dioxid. The ferrous solution is introduced through the 

 tube caiTying the gas by means of a 100 cc. pipette, care being taken to do this and 

 to lieat the solution so that a regular evolution of gas occurs. After washing the 

 tubes with boiled distilled water the excess of ferrous chlorid in the solution is 

 titrated witli potassium permanganate. 



On a new volumetric method of determining nitric acid, L. Debourdeaux 

 {Bui. Soc. Chim. Paris, 3. ser., 31 {1904), -^Vo. 1, pp. 3-6). — Previously noted from 

 another source (E. S. E., 15, p. 224). 



On the dissociation of alkaline carbonates, P. Lebeau {Compt. Rend. Acad. 

 Sci. Paris, 137 {1903), Xu. J6, pp. H55-1^57). 



Composition of commercial alkalis ("concentrated lye"), G. E. Colby 

 {California Sta. Ppt. 1902-3, p. 92). — The sodium hydroxid m 5 samples of soda lyes 

 examined was respectively 97.6, 92.2, 87.5, 82.4, and 68.5 per cent. The potassium 

 hydroxid in 2 samples of potash lyes was respectively 71.4 and 69.1 per cent. 



The conversion of calcium oxalate to the sulphate, A. N. Clark {Jour. Amer. 

 CItem. Soc, 26 {1904), Xo. 1, pjp. 110, 111). — In the method proposed the platinum 

 crucible containing the oxalate saturated as usual with sulphuric acid is partially 

 embedded in asbestos or calcium sulphate contained in a porcelain crucible about \ 

 in. larger in diameter than the platinum crucible. "The top portion of the i)lati- 

 nimi crucible is heated first and remains hotter than the l)ottom so that the excess of 

 sulphuric acid boils out from tlie toi> of the precipitate, instead of from the bottom. 

 The excess of acid is driven off in about one minute; the platinum crucible is then 

 removed from the porcelain crucible and set f)ver the flame until it is brought to a 

 red heat." 



The determination of alkalis, especially in plant substances, H. Neubauer 

 {Zlsehr. Analijt. Chem., 43 {1904), Xo. l,pp. 14-36). — To the coarsely ground material 

 add a mixture of nitric acid of 1.4 sp. gr. and concentrated sulphuric acid (30 cc. of 

 nitric acid for 5 gm. of seeds, 40 cc. for 5 gm. other materials) and allow to stand 1 

 hour without heating. Then apply heat cautiously and digest until the solution 

 becomes almost colorless. Allow to cool slightly, add about \ cc. of concentratetl 

 nitric acid, and heat again. Repeat the treatment with nitric acid to complete 

 the oxidation. Cool, add at least an equal volume of water, and warm to expel 

 nitrous fumes. Evaporate to dryness in a platinum dish and heat to redness. Take 

 up in warm water acidified with hydrochloric acid and evaporate to dryness to expel 

 hydrochloric acid. Add phenolphthalein and freshly prepared milk of lime until a 

 saturated solution of calcium hydroxid (shown by a strong red color) is obtained. 

 Make to definite volume (125 cc. for example), mix, allow to stand h hour, and filter. 



In an aliquot of the filtrate precipitate lime by adding first oxalic acid and then 

 ammonia, taking special care to secure neutrality and complete precipitation without 

 a great excess of ammonium oxalate. Filter through a small filter into a platinum 

 dish, wash with cold water c(jntaining a little ammonium oxalate, evaporate to dry- 

 ness, and drive off ammonium compounds. Take up in hot water, add ammonia, 



