CHEMISTRY. 1015 



13 gm. of ainmoniniii nitrate; then the nioly])dic sohition can be added imnu'(hately, 

 for tlie aninioninni nitrate eools the Mointion down to wliere it is sale to preciiiitate 

 and no waiting to cool is necessary as is tlie case if anuuoninni nitrate is ailded before 

 the exc^ess of acid is nentraHzed." 



The determination of calcium, strontium, and barium as oxalate, C. A. 

 Pktkks [Ztuchr. Anorgnu. (JJicm., 20 {1001), No. 1, pp. 145-155). — -Methinls in which 

 these substances are deterniinetl Ijv titration of tlie oxalates with permanganate solu- 

 tion are described in detail and a number of determinations are reportetl. From 

 these the conclusion is drawn tiiat calcium may be accurately determined by titration 

 of the oxalate with permanganate solution if hydrochloric acid (with the addition 

 of a manganous salt) is used as a solvent. Practically complete pri'cipitati(jn of 

 strontium by ammonium oxalate may be obtained in solutions containing one-fifth 

 l)y volume of 85 per cent alcohol. Almost complete precipitation may be ol)tained 

 in water solutions if the dilution does not exceed 250 cc. The strontium oxalate may 

 be accurately titrated with permanganate solution either when sulphuric acid or 

 hydrochloric acid (with the addition of manganese oxalate) is used as the solvent. 

 Barium may be practically completely iirecipitated V)y means of ammonium oxalate 

 in solutions containing one-third by volume of 85 per cent alcohol. The oxalate 

 may be accurately titrated with permanganate solution when dissolved in hydro- 

 chloric acid with the addition of manganous salt. The strontium and barium oxa- 

 lates may be converteil into carljonate l)y ignition and weighed as such. 



On the determination of sulphur in soils, T. Pfeiffeu and R. Riecke {Mitt. 

 Landw. Inst. Univ. Breslau, 1 {1001), No. 5, pp. 47-51). — The presence of large 

 amounts of iron was found to interfere with the accurate determination of sulphuric 

 acid by the ordinary method of removing iron with ammonia and iirecipitating sul- 

 phuric acid with barium chlorid in acid solution. The tests of different methods 

 reported indicate that accurate results can be obtained only by fusion of the soil with 

 potassium liydroxid and oxidizing substances. 



Determination of nitrogen, F. Jean {Ann. Chim. Anahjt., 6 {1001), ji. 441; ahs. 

 in Chem. Cenlbl., 1002, I, No. 5, p. 333). — A distilling apparatus, especially a device 

 for preventing solutions from being carried over into the condenser, is descrit:)ed. 

 For decomposition of the mercury compounds the author uses sodium hypophos- 

 phite instead of sodium sulphid. 



Analysis of -water, H. Potell {Bol. Agr. SCio Paulo, 2. scr., 1001, No. 10, pp. 

 635-640). — This article discusses methods of analysis. 



The evolution of the oxygen absorption test in water analysis, J. B. Weems 

 {pp. 8). — This is a paper read before the Iowa Engineering Society at its thirteenth 

 annual meeting at Davenport, January 16-19, 1901. A brief review of the history of 

 this test is given, with a list of references to literature. 



A delicate method for the detection of formaldehyde, C. Arnold and C. 

 Mentzel {Ztsdir. Untersuch. NctJir. n. Genus.'^mtL, 5 {1002), No. 8, pp. 353-356). — To 

 5 cc. of an alcoholic extract of the material under examination are added 0.08 gm. of 

 phenylhydrazin chlorid and 4 drops of a solution of ferric chlorid. Upon the addi- 

 tion of 10 to 12 drops of concentrated sulphuric acid, with cooling of the solution, a 

 red color appears. 



The quantitative estimation of formaldehyde, L. V.\nino and E. Seitter 

 {ZtscJir. Anah/t. ('hem., 40 {1001), No. 0, pp. 587-580). — The estimation of formalde- 

 hyde by the proposed method is made l)y the use of potassium permanganate, as 

 often previously employed, and the use of strong suli)huric acid and hydrogen 

 peroxid. 



In carrying out the method 35 cc. of two-tenths normal potassium permanganate 

 solution is placed in a glass stoppered flask of about 250 cc. capacity. There is added 

 a previously mixed and cooled solution of 30 gm. of concentrated sulphuric acid and 

 50 gm. of water. There is then added slowly, with constant shaking, 5 cc. of about 



