414 EXPERIMENT STATION KECORD. 



Rapid saponification of fats for titer determination, C. V. ZouL (Jovr. 

 Indus, (ind l'Jn(/iii. Cliciii., .1 (I'.HO), No. II, pp. //lU, //«C).— Practicully the 

 same ijioHukI a.s described above. 



Saponificatioji of fats for titer determination, A. Campbell and C. P. Long 

 (Jour. Indus, and Engin. Chern., 3 (VJll), No. 2, p. IVi). — A polemic in regard 

 to the question of priority for the Zoul method. 



The absorption spectra of oils, K. Makcille (Ann. Falsif., 3 (WW), No. 2//, 

 pp. Jf23-Ji2'j). — Some observations in regard to th(! absorption spectra of olive, 

 peanut, sesame, cottonseed, linseed, and castor oils, with particular reference 

 to the absorption spectra due to the presence of chlorophyll in these oils. 



On the interpolation method of oil analysis, J. J. Kk,sslek and G. K. Mathia- 

 SON (Jour. Indus, and Engin. Chcm., 3 (1911), No. 2, pp. 66-72, flgn. 10). — 

 This work was done with castor, cottonseed, and linseed oils and a resin and 

 mineral oil. According to the authors, " certain tests commonly used in oil 

 analysis (the viscosity, flash test, fire test, and Maumene test) have been 

 shown to follow a law of mixtures which is not an additive one, and hence if 

 Interpolations are made from the data obtained from such tests the results will 

 be in error to a very considerable amoinit in some cases. 



"These results call attention to the possibility of many other physical tests 

 being uonadditive. They also suggest the possibility that certain chemical 

 tests, in which a comr)letc chemical reaction does not occur, may not be additive. 

 The saponification number is shown to be an additive relationship even for 

 small percentages of one oil in presence of another. The MaumenC* test as 

 carried out at the present time is incapable of yielding results which can be 

 used in making a quantitative analysis by the interpolation method." 



The dimethyl sulphate test of creosote oils and creosote dips; a substitute 

 for the sulphonation test, R. M. Ciiapin (U. S. Dcpt. Agr., Bur. Anim. Indus. 

 Circ. 167, pp. 7). — Although the sulphonation lest for examining coal-tar creo- 

 sote sheep dips in theory is simple and rational, its use by inexperienced per- 

 sons is often unsatisfactory and is always disagreeable and tedious. In view 

 of these facts, the author has adopted the Valenta test" for the examination 

 of such preparations. This test is based on the assumption that dimethyl sul- 

 phate is niiscible in all proportions with the closed-chain hydrocai'bons. while 

 the open-chain hydrocai'bons are not soluble in it at all. Some comparative 

 results bctvvccMi the Valenta test and the sulphonation test are given. 



Lime-sulphur spray, J. E. IIakkis (Michigan 8 to. Tech. Bui. 6, pp. 3-0). — 

 Recognizing the need of improvements in the way of accuracy and rajtidity for 

 the analytical methods usually emi)loyed in the analysis of lime-sulphur spray, 

 the author, as a preliminary to work reiwrted elsewhere, investigated the 

 existing methods for total sulphur, monosulphid sulphur, thiosulphate sulphur, 

 sulphite and sulphate sulphur, and calcium oxid. The work is summarized as 

 follows : 



"The total sulphur is determined by oxidizing the sulphur present to the 

 sulril'.'ito form, using sodium peroxid as the oxidizing agent and precipitating 

 and weighing as barium sulphate. 



"The monosulphid sulphur is determined by titrating a 2.5 cc. sample of the 

 diluted solution with decinormal iodin until the yellow color disappears. The 

 number of grams per 100 cc. of the original solution is given by the com- 

 putation Cc. iodin X0.001GX 1000 



"The thiosulphate sulphur is determined by continuing to add iodin solution 

 after the monosulphid end point has been reached until we have one drop in 



«Chem. Ztg., 30 (1906), No. 25, pp. 266, 267. 



