116 



SCIENCE 



[Vol. LVI, No. 1439 



Plastometer tests on alkaline thin ioiling corn 

 starches: C. E. G. PoRST and M. Moskowptz. 

 Corn starches of various fluidities ranging from 

 ten to fifty (as determined by the Corn Products 

 Refining Company's funnel method) were pre- 

 pared having alkalinities varying between acid to 

 phenolphthalein up to .12 per cent, alkali. The 

 pastes from these starches were then tested on 

 the plastometer. Results show that the paste 

 from starches which were just about neutral to 

 phenolphthalein were firmer than those that re- 

 acted acid. As the alkaUuity of the starch 

 increased, the pastes became smootlier and more 

 elastic. Methods for preparing the pastes were 

 standardized and made uniform. Two concen- 

 trations of starch pastes were used in the tests. 

 Curves were plotted in the regular manner, and 

 also on logarithmic paper. The equation for the 

 flow in cubic centimeters per second in terms of 

 a function of the pressure was- determined from 

 the logarithmic curve. 



The detennination of gums in sugar products: 

 H. T. Ruff and J. R. Withrow. The various 

 analytical methods proposed for gum determina- 

 tion in sugar products were studied and com- 

 pared for the purpose of determining the method 

 best adapted for control work. Some proposed 

 methods compared with each other on solutions 

 of pure gums in water or refined sugar solutions, 

 but were not comparable on customary sugar 

 products. The method of precipitating the gums 

 ■n-ith ethyl alcohol acidified with hydrochloric acid 

 was found to be the most suitable and was fur- 

 ther studied to determine concentrations of alco- 

 hol and acid. While we have no claim to orig- 

 inality in method adopted, the technique is 

 original and is definitely expressed to make re- 

 sults obtained rapid and reBable. It was found 

 with certain precautions denatured or wood alco- 

 hol could substitute for ethyl alcohol. Curves 

 are plotted to show the influence of concentration 

 of alcohol and acid. 



The determination of the p„ value of commer- 

 cial glucose as a substitute for the candy test: 



O. A. SjOSTROM. 



Some notes on the determination of reducing 

 : B. B. Ross. 



An improved precision refractometer for the 

 sugar industry: Wareen P. Valentine. Tliis 

 paper contains a short reference to the develop- 

 ment of the refractometer and its increasing ap- 

 plication in the sugar industry; errors and ap- 

 proximations in the present sugar tables and the 

 consequent demand for highly standardized data; 

 the construction and test by the Bureau of 



Standards on a special refractometer, and the 

 final development of an instrument to utilize new 

 sugar tables now in process by the Bureau of 

 Standards. 



The observance of mutarotation in the polar- 

 ization of raw cane sugar: M. H. Wiley and 

 C. A. Browne. In the polarization of two dete- 

 riorated sugars from the Cuban crop of 1921, the 

 direct polarization immediately after solution de- 

 creased at the end of three hours in one instance 

 from 90.85 to 90.15 and in another instance 

 from 90.15 to 89.50. The sugars had undergone 

 considerable inversion during storage from the 

 attack of micro-organisms, and the mutarotation 

 is probably due to the very perceptible drying 

 out of the sugar in the bags and the separation 

 of the high rotating modification of dextrose in 

 the sirupy films which cover the crystals of 

 sucrose. 



Note on the color range of cane sirups and 

 molasses: F. W. Zekban. Dr. Zerban reported 

 an interesting series of color measurements on 

 cane syrups made according to the Bureau of 

 Standards method with two simplifications, both 

 of which are objectionable — ^the use of Kiesel- 

 guhr to obtain an optically pure filtrate and the 

 use of the Hess-Ives instrument with white light. 

 The color values showed a general correlation 

 with the purity. 



Manufacture of plantation standard granu- 

 lated sugar with and without activated char: 

 C. E. CoATES. An outline is given of the various 

 methods for making standard granulated sugar 

 in the sugar house, including: Its manufacture 

 direct from the cane without the use of char, 

 using sulfitation or carbonation of the juice; the 

 non-chemical process using heat and Kieselguhr, 

 the clear juice being given immediately a char 

 filtration; making carbonated or suMted syrup, 

 which syrup is subjected directly by a char filtra- 

 tion; the manufacture of 96 test sugar as usual 

 and immediately remelting and treating the 

 melted sugars with char. Much improvement has 

 been made during the last few years, both in 

 quality of product and in yield. 



The decolorising power of hone char (prelim- 

 inary report) : Paul M. Horton. It has been 

 claimed by Patterson that the decolorizing power 

 of boneblack is due to a nitrogenous base which 

 can be extracted by concentrated sulfuric acid. 

 Patterson's experiments have been repeated, the 

 results leading to the conclusion that the nitroge- 

 nous base mentioned has no special decolorizing 

 power, and that the decolorizing power of bone- 

 black must be due to other causes. The extract 



