14 EXPERIMENT STATION" RECORD. 



The preservation of milk samples destined for analysis, G. Denig^s {Ann. 

 Falsi/., 5 (1012), No. 50, pp. 559-561) .—Desjyite the conclusion of Rocques, noted 

 above, tbat bichromate of potash is a satisfactory preservative for milk samples, 

 it is maintained thp.t the method does not work well in everyday practice. The 

 recommendation of Dubois for the substitution of a solution of 50 gm. of 

 phenol in 10 cc. of 95 per cent alcohol, using 1 cc. of this preservative to 100 cc. 

 of milk, wns found very satisfactory by the author. Some of Dubois's analyses 

 made in 1900, also an analysis made of one of the samples collected in 1900 and 

 reanalyzed in 1910, are shown. Practically no change in the composition of 

 the sample took place. 



The detection of peanut oil in olive oil, L. Abler (Ztschr. XJntersucli. Nahr. 

 u. Genussmtl, 23 {1912), No. 12, pp. 676-679, fig. i).— A description is given 

 of a modification of the Franz method in which it is possible to detect an addi- 

 tion of at least 5 per cent of peanut oil to olive oil. 



One cc. of the oil and 5 cc. of an 8 per cent alcoholic potassium hydrate solu- 

 tion (80 gm. of potassium hydrate treated with alcohol and enough 90 per cent 

 alcohol to make 1 liter) are placed in a 100 cc. Erlenmeyer flask provided with 

 an 80 cm. cooling tube. The mixture is heated for 4 minutes in a boiling water 

 bath, shaken frequently, and cooled to 25° C. ; 1.5 cc. of dilute acetic acid (1 vol- 

 ume acetic acid and 2 volumes water) and 50 cc. of 70 per cent alcohol by vol- 

 ume are added ; the mixture is then shaken and allowed to stand. 



If the solution does not clear up. it should be heated until clarification has 

 taken place, then cooled to exactly 16°, shaken repeatedly at this temperature 

 for a period of 5 minutes, and if no definite turbidity is noted, cooled to 15.5°. 

 If no turbidity is produced after another 5 minutes, the oil contains less than 

 5 per cent of peanut oil. 



The detection of peanut oil in olive oil according to the Franz- Adler 

 method, H. Luers {Ztschr. Untersucli. Nahr. u. Genussmtl., 2Ii {1912), No. 11, 

 pp. 683, 684)' — Two samples of olive oil which were examined according to the 

 Franz-Adler method showed a marked precipitate at 16° C, which pointed, 

 according to the originators of the test, to the presence of about 5 per cent of 

 peanut oil. On the other hand, when the oils were examined by the lead salt 

 method of Torelli and Ruggeri (E. S. R., 10, p. 413), peanut oil was apparently 

 absent. A chemical study then made of the oils showed that the precipitate 

 produced in the Franz-Adler test in these instances consisted of a potassium 

 salt of myristic acid, and consequently it was assumed that these oils were 

 characterized by a high myristic acid content. The amount of acid added in 

 the Franz-Adler test is considered insufficient to cause the liberation of the 

 entire acid in every instance, and consequently a precipitate of the acid salt is 

 produced at from 15 to 16°. 



On the basis of the above findings the method was modified. 



Technical accounting and chemical control in sugar manufacture, D. L. 

 Davoll, Jr. {Jour. Indus, and Engin. Chem., 5 {1913), No. 3, pp. 231-23^; 4, pp. 

 S1S-S19, figs. 6). — A detailed description of the topic, which includes the 

 chemical methods utilized in sugar control. 



The sugar content of maize stalks, G. N. Blackshaw {So. African Jour. 

 Sci., 9 {1912), No. S, pp. .^2-^S).— Continuing previous work (E. S. R., 27, p. 

 314), the author reports results of more extensive experiments with Hickory 

 King. Boone County, Salisbury White, Golden Eagle, and Sweet corn, sown 

 November 9. From a portion of each plat, the cobs were removed in a milky 

 condition on April 2, and the juice of stalks selected from the cobbed and 

 uncobbed portions analyzed periodically until the crop reached maturity. 



All of the cobbed plants, with the exception of Sweet corn, examined between 

 April 10 and May 23, i. e., from 8 to 51 days after removing the cobs, showed 



