314 EXPERIMENT STATION RECOED. [Vol.38 



iu a suitable burette, and after reduction of the volume obtained to standard 

 conditions the amount of formic acid is easily calculated. 



In samples which contain carbonates, bicarbonates, oxalates, etc., these ma- 

 terials are removed by precipitation with a 10 per cent solution of calcium 

 chlorid and an aliquot of the filtrate oxidized as in the regular procedure. 



Analytical data obtained in the analysis of pure solutions of sodium formate 

 and solutions with the addition of carbonate, bicarbonate, and oxalate indicate 

 that the method is accurate and reliable for technical determinations. 



The determination of salicylic acid in foods, H. D. Steenbergen {Chem. 

 Weekbl., I4 (1917), No. 39, pp. 914-921).— A modified iodometric method is de- 

 scribed which consists of treating the extract containing salicylic acid with 

 a bromate-bromid solution and a ^-^ -normal bromin solution, setting the bro- 

 min free with hydrochloric acid (.specific gravity 1.13), and after 15 minutes 

 adding an excess of potassium iodid and titrating the iodin set free with 

 standard thiosulphate. The reactions taking place are indicated as follows : 

 CeHi (OH) COOH-F8Br=CeH2Br30Br+4HBr+C02 

 C6H2Br30Br+2KI=C6H2Br30K+KBr+2I 



Comparative analytical data of the usual acidimetric and the modified iodo- 

 metric methods are submitted, together with data on the extraction of the, 

 salicylic acid from the original samples. 



A new and simple procedure for determining the fineness of wheat flour, 

 F. Pereacini {Stas. Sper. Agr. Ital, 50 (1917), No. 3-5, pp. 250-252).— A pro- 

 cedure which consists of treating a 5-gm. sample of the flour with 1 per cent 

 copper sulphate solution and comparing the color which develops with a 

 standard sample, similarly treated, is briefly described. 



Some new methods for determining the fineness of flour, G. Lo Priore (Stas!. 

 Sper. Agr. Ital., 50 (1917), No. 3-5, pp. 253-259).— The author discusses the 

 colorimetric method previously described, and also a method based on the 

 determination of the pentosans in the sample. 



The conservation of tomatoes, P. Guarnieri (Staz. Sper. Agr. Ital., 50 

 (1917), No. 3-5, pp. 245-249). — This article deals with the organoleptic, physi- 

 cal, and chemical examination of tomatoes and the consideration of the ana- 

 lytical results obtained. 



A note on the determination of the nonfatty solids in milk from the 

 specific gravity at tropical temperatures, H. A. Tempany (West Indian Bui., 

 16 (1917), No. 3, pp. 262-264).— A table showing the percentage of nonfatty 

 solids in milk corresponding to lactometer readings at 30° C. (88° F.) has 

 been constructed and is submitted, together with some analytical data which 

 indicate the accuracy attained in the use of the table. The table was con- 

 structed to obviate the usual procedure of cooling the sample to temperatures 

 required for the usual conversion tables. 



A study of the estimation of fat in condensed milk and milk powders, 

 C. H. Biesterfeld and O. L. Evenson (Jour. Indus, and Enyin. Chem., 9 (1917), 

 No. 12, pp. IIII-III4, fig. 1). — The authors have studied the usual errors in- 

 herent in the Rose-Gottlieb method and have compared it with a modified 

 method in which a small amount of acetic acid, as an aid in separating the fat 

 from the casein, mixtures of petroleum ether, ethyl ether, and ethyl alcohol 

 (which are recoverable for repeated use), and a modified Rohrig tube (E. S. 

 R., 16, p. 1050) are used. The two mixtures used in the modified method con- 

 sist of (1) 400 cc. of petroleum ether, 200 cc. of ethyl ether, and 20 cc. of 95 

 per cent ethyl alcohol, (2) 350 cc. of petroleum ether, 280 cc. of ethyl ether, and 

 63 cc. of 95 per cent ethyl alcohol. The modified procedure is as follows : 



