804 EXPERIMENT STATION RECOED. [Vol. 38 



around the soil particles. The method, which will be described in detail in a 

 later paper, allows of the direct determination of the concentration of the soil 

 solution and of the amounts of each of the solutes contained therein, and offers 

 a means of obtaining quickly and directly large portions of the soil solution as 

 it exists naturally under field conditions when crops are growing. 



The valuation of lime for various purposes, R. K. INIeade {Jour. Indus, and 

 Engin. Chevi., 10 {1918), No. 3, pp. 214-219, fig. i).— This is a collection of ma- 

 terial on the more important uses of lime in the arts, the classification of 

 limes according to chemical composition, etc., the properties which lime should 

 possess to be acceptable in each industry, and the methods most generally 

 employed for the chemical analysis of lime. 



Notes on the analysis of molasses, H. S. Walker {Jour. Indus, and Engin. 

 Chem., 10 {1918), No. 3, pp. 198-202). — Experimental evidence indicates that in 

 Clerget sucrose determinations in waste molasses the method of clarification 

 with lead subacetate solution as recommended by the Hawaiian Chemists' 

 Association yields results from 0.5 to 0.7 per cent too high, due to the large 

 volume occupied by the lead precipitate. Clarification with dry lead subacetate 

 is apt to run a little low, especially if an excess of lead is used. A modifica- 

 tion of the dry lead method which gives more correct results is described. 



A comparison of the proximate and mineral analysis of desiccated skim 

 milk with normal cows' milk, E. P. Harding and H. Ringstrom {Jour. Indus, 

 and Engin. Chem., 10 {1918), No. 4, PP- 295-291). — Proximate and mineral 

 analyses are reported of four different samples of commercial desiccated skim 

 milk and the results compared with previous analyses of skim milk powders 

 and with normal cows' milk. The color, odor, and emulsifying power of the 

 samples were noted. 



The data show that the percentages of the mineral constituents in the four 

 samples agreed quite closely, but did not agree well with those found by other 

 analyses. The sulphuric acid, calcium and magnesium oxids, and phosphoric 

 anhydrid were higher and the ferric oxid lower than in other methods. The 

 high phosphorus and calcium content may be due to phosphate and calcium 

 added as emulsifiers. 



The proximate analyses agreed quite closely with previous analyses. The 

 color, odor, emulsifying power, high protein, low lactose, high calcium and 

 phosphorus content, and low total proximate analysis of one of the samples 

 indicated that it was not genuine desiccated skim milk powder. 



Tentative standard methods for the sampling' and analysis of commercial 

 fats and oils {Jour. Indus, and Engin. Chem., 10 {1918), No. 4, pp. 315-320, 

 fig. 1). — To the methods previously noted (E. S. R., 38, p. 206) have been added 

 methods for the determination of the iodin value according to the Wijs method 

 and the saponification or Koettstorfer number. 



The determination of arsenic in insecticides by potassium iodate, G. S. 

 .Tamieson {Jour. Indus, and Engin. Chem., 10 {1918), No. 4, PP- 290-292) .—The 

 author has applied the iodate titration method as first described by Andrews 

 (E. S. R., 15, p. 226) to the determination of total arsenic in arsenical insecti- 

 cides or fungicides, and compared the results with those obtained by the official 

 iodimetric method (E. S. R., 35, p. 207). The method is described in detail 

 and data reported of the determination of arsenic in several samples of Paris 

 green and zinc arsenite. 



The results of the test analyses agree closely with those obtained by the 

 official method. "This accurate method is not only quicker, but is simpler 

 than the iodin titration. The very definite and remarkably sharp end-point, 

 the great stability of the potassium iodate solution, and the readiness with 



