CHEMISTRY. 551 



then sodium carbonate solution until a precipitate just forms. The chlorin is then 

 determined by titration with standard silver nitrate, using potassium rhromate as 

 indicator." 



The results of 12 analyses of mixtures of potassium iodid and bromid and sodium 

 chlorid are reported. These show a very close agreement between the calculated 

 and determined amounts of the halogens. 



On the formation of nitric acid by electrical energy, C. W. Volney ( Trans. 

 Amer. Eledro-Cheni. Soc, 1903, pp. 285-289; ahs. in Jour. Chim. Phys., 1 {1903), No. 

 4, ]). 325). — In experiments to determine the rapidity of decomposition of NO into 

 NO2 and N by means of electrical discharges, the following results were obtained: In 5 

 minutes 2.7 per cent, in 10 minutes 3.3 per cent, ni 20 minutes 3.58 per cent of NO 

 was decomposed. Various equations explaining the reaction are given. 



The oxidation of atmospheric nitrogen by electrical discharges, F. von 

 Lepel {Ber. Deut. Clievi. Gesell, 86 {1903), pp. 1251-1260; abx. in Jour. Cluui. Phys., 

 1 {1903), No. 4, p. 310) . — After a brief review of the work of other investigators on 

 this subject, the author describes a large series of experiments made to determine the 

 influence of various factors, such as the nature of the electrodes, the rapidity of rota- 

 tion of the anodes, and the nature of the solution in the apparatus, upon the produc- 

 tion of nitric acid by means of a continuous current. 



The determination of nitrogen by the Kjeldahl method, S. P. L. Sorensen 

 and C. Pedersen [Ztsdir. Physiol. Chrm., 39 {1903), Xo. 6, pp. 513-525, fig. i).— The 

 Kjeldahl method was fomid to give good resnlts with such substances as creatin, 

 creatinin, and uric acid. The results, however, were believed to be a little too low; 

 while those by the Dumas method was considered a little too high. 



Methods of analysis of separator skim milk, C. Barthel {Nord. Mejeri Tidn., 

 18 {1903), No. 35, pp. 71, 72). — A comparison of the Adams and Gottlieb methods 

 for the analysis of skim milk. The results presented show that if the fat content in 

 the skim milk is greatly increased through the application of self-cleaning pasteur- 

 izers, the stirrer of which is turned at a considerable speed, the Adams method fails 

 to show any appreciable increase in the percentage of fat in the skim milk, while 

 Gfittlieb's method gives all the fat contained therein. — f. w. woll. 



A further contribution to the methods of fat determination, M. Muller 

 {FiMinf/s Landw. Ztg., 52 {1903), Nos. 21, pp. 767-771; 22, pp. 831-834) .—The 

 author found it extremely difl&cult, if not impossible, to prepare casein free from fat 

 by ordinary methods of fat extraction. In tests with casein, beef, and yeast the Leh- 

 mann method was considered the most satisfactory. The Soxhlet method gave results 

 much too low, and the Dormeyer method much too high. The percentages in the 

 case of yeast were 1.891 by the Soxhlet method, 4.908 by the Lehmann method, and 

 5.456 T)y the Dormeyer method. In tests with the brains of horses the results by 

 the 3 methods were respectively 49.924, 50.192, and 50.75 per cent. The 3 methods 

 were therefore considered of nearly equal value on substances rich in fat. 



Olive oil and its substitutes, L. M. Tolman and L. S. Munson ( U. S. Dept.Agr., 

 Bureau of Chemistry Bui. 77, pp. 64, pis. :?).— The nature and extent of the investiga- 

 tion reported in this bulletin are outlined in an introductory note by W. D. Bigelow, 

 Chief of Food Laboratory. The bulletin proper contains statistics of the olive-oil 

 trade; an account of the manufacture of olive oil; the methods of analysis used, with 

 a full discussion concerning the interpretation of results; and analyses of a number 

 of salad oils sometimes fraudulently substituted for olive oils, olive oils of known 

 origin, and of commercial olive oils. 



A briefer account of the work relating to the pure olive oils and the olive oil sub- 

 stitutes has been noted from another source (E. S. R., 15, p. 223). The l)ulletin is 

 summarized by the authors as follows: 



"(1) The olive oil consumed in this country is largely imported from France and 

 Italy. The amount produced in California is relatively small, although reports war- 

 rant the statement that California is cai)able of supplying the entire home demand. 



