AGRICULTURAL CHEMISTRY — AGROTECHNY. 813 



making a direct polarization and a polarization after inversion, and the resnlts 

 obtained are calculated by Ilerzf eld's method. The chemical method in which 

 the ralHnose is converted into mucic acid by oxidation with nitric acid does 

 not give satisfactory results. 



The purpose of this work was to elicit which of the methods used at the 

 present time for determining sucrose in beets, i. e., alcoholic digestion and hot 

 aqueous digestion, is the most satisfactory for estimating the amount of 

 raffinose, and in what way lead subacetato affects its estimation. The hot 

 aqueous digestion method was the method finally recommended. Where no 

 lead subacetate or an insufhcient amount was used some rallinose was detected, 

 but when as much as 10 cc. of subacetate of lead solution to the normal weight 

 was employed no ralfinose was found. In some experiments in which rafhnose 

 was added, almost the same amount was noted in the llnal calculation. The 

 conclusion is reached that there need be no fear of forming lead raffinates in 

 the hot aqueous digestion method. 



Examination of commercial starch {Ztschr. Landw. Vcrsuchs-w. Ostcrr., 15 

 (1912), Ko. 11, pp. 1217-1220) .—The methods described are those adopted by 

 the Austrian Association of Agricultural Experiment Stations, and are for the 

 purpose of supplying means for the uniform judgment of starches, especially 

 potato starch, according to the standard set up by the Vienna Stock Exchange. 

 The methods include those for color, spreading power, detection of chlorin and 

 inorganic acids, determination of water (indirect determination of the starch), 

 determination of ash, inorganic h3ading materials, aciditj', and the direct de- 

 termination of starch. 



Examination and judgment of vegetable tanning substances [Ztschr. 

 Landw. Tersuchsw. Osterr., 15 (1912), No. 9, pp. 1122-1146). — ^A discussion of 

 methods and criterions for the valuation of vegetable tanning materials as 

 adopted by the Austrian Association of Agricultural Exi^riment Stations. The 

 determinations to be made on tannin barks are tannins, nontannins, and possibly 

 moisture; in extracts, tannins, nont;annins, insoluble substances, moisture, and 

 possibly ash. The last constituent will give a clew as to whether the extract 

 has been sulphited. 



Determination of fat in feeds, with particular reference to shaking out 

 with trichlorethylene in the cold, R. Neumann (Landw. Vers. Stat., 79-80 

 (1913), pp. 701-736, fig. 1). — The results obtained from various feeds showed 

 that trichlorethylene was satisfactory for estimating the fat, etc., in this class 

 of material. It was only necessary to extract in the cold. When the material 

 under examination contains much protein, e. g., meat, fish meal, or much fat, 

 e. g., ajowan residues or millet polish meal, it must first be treated according 

 to von Hissink's method. Sesame cake, when extracted for a long time with 

 ether, yields nonfatty substances which are deposited in the extraction flask, 

 but by shaking this material with trichlorethylene in the cold, these substances 

 are not extracted. 



Homemade cider vinegar, W. G. Sackett (Colorado St a. Bui. 192 (1913), 

 pp. 3-15). — In this bulletin the use of waste apples is urged for the preparation 

 of cider vinegar. The various steps in the process are described and emphasis 

 is laid especially on the use of pure cultures of yeast and bacteria for this 

 purpose. The cultures are supplied at a nominal cost by the station. 



Pineapple vinegar, W. P. Kelley (Hawaii Sta. Rpt. 1913, p. 34)' — In the 

 canning of pineapples there results an enormous waste of juice which amounts 

 to hundreds of thousands of gallons per annum. Some of the juice is utilized 

 for making sirup and. to a limited extent, for preparing bottled pineapple juice. 



Attempts to convert the juice into vinegar with the rapid vinegar process were 

 made but the results were not entirely satisfactoiy. " On an average the 



