118 



SCIENCE 



[N. S. Vol. LIV. No. 1388 



weight of 26 grains of sugar in 100 c.c. the vol- 

 Times of the lead precipitates in the case of the 

 Cuban sugars of polarization 90.95-96.00 varied 

 from 0.10 to 0.12 c.c. and in case of the Philip- 

 pine sugar of polarization 78.30-87.80 from 0.32 

 ■to 0.48 c.c. The volume of the lead precipitates 

 was not found to increase during deterioration of 

 the sugar. 



1. Th^ saccharimetrio graduation of polarime- 

 ters with a graduated circle which employ yellow 

 sodium light. 2. The graduation of saccharrime- 

 ters with a quartz compensattion : A. Jobin. The 

 author employs as a basis for the saecharimetric 

 graduation of his instruments the following fun- 

 damental values: _)_ 66.5 for the specific rotation 

 of sucrose for the D ray; -f 21.7182 for the 

 rotation of the standard 1 mm. plate of quartz for 

 the D ray. The variations in these fundamental 

 values with concentration of sugar solution, with 

 temperature and with source of light are con- 

 sidered, and a mathematical discussion is given of 

 the various corrections which need to be applied 

 in the saecharimetric graduation of polarimeters 

 and of quartz wedge saccharimeters. Light filters 

 should serve not for unifying, but for purifying 

 the source of illimiination. The ofiicial rules re- 

 lating to the bichromate filter should be revised. 



Examination of sugar crystals iy projection: 

 George P. Meade. Samples of raw sugar from 

 several factories are classified daily as to size 

 and regularity of crystal. A "balopticon, " with 

 vertical attachment, throws an image of a small 

 portion of the sample on a screen, magnifying ten 

 diameters. Squares drawn on the screen corre- 

 spond in size to an arbitrary scale of ten, and the 

 observer compares the image of the crystals with 

 the squares, determining the size to the nearest 

 whole number of the scale. The projection also 

 shows the regularity and form of the crystals, 

 and abnormalities are noted. 



The rare sugars, their purity and tests: E. B. 



BL.4CK. 



A study of ieet gum. (!) Separation from 

 final molasses: H. S. Paine and C. F. Walton. 



Solubility of dextrose in water: E. F. Jackson 

 and C. L. Gillis. 



Some observations from the beet sugar industry : 



H. E. ZiTKOWSKI. 



Sugar filtration in factories and refineries: H. 

 J. Eunton, Jr. 



Colloids in beet sugar house liquors and products: 

 H. S. Paine, G. G. Church and F. W. Eetnolds. 



Experiments with sugar cane seedlings in St. 

 Croix: Longpield Smith. Experiments con- 

 ducted during 1920 upon the St. Croix seedling 

 canes^S. C. 12/37, S. C. 12/4, S. C. 14/93, and 

 S. C. 13/13 — gave in comparison with the stan- 

 dard ribbon cane grown for comparison alongside 

 the following yields of cane and of sucrose per 

 acre, as obtained by a small 3 roller mill driven 

 by a 5 h.p. gasoline engine. 



Tons Cane Pounds Sucrose 



With a stronger mill such as used in a modern 

 sugar factory the above yields of sucrose per acre 

 would be at least 50 per cent, higher. The new 

 St. Croix seedlings are excellently adapted to local 

 conditions and are rapidly finding favor not only 

 in St. Croix but in Porto Eico and other West 

 Indian islands. The S. C. 12/4, when ripe, yields 

 a juice containing 20 per cent, sucrose. The 

 juice of ripe ratoons has been known to yield 

 24 per cent, of sucrose. 



A precipitate obtained from cane juice after 

 clarification with Kieselguhr and decolorizing car- 

 bon: V. BlECKNER. 



Experiments with ScJioorl's volumetric method 

 for determining reducing sugars: C. A. Browne 

 and G. H. Hakden. In Sehoorl's volumetric 

 method for determining reducing sugars, the un- 

 reduced copper of the Eehling solution is deter- 

 mined in presence of the reduced Cu^O by means 

 of n/10 thiosulphate solution after acidifying with 

 sulphuric acid and adding potassium iodide. The 

 difference between the total copper originally pres- 

 ent and the unreduced copper gives the copper 

 reduced by the sugar. Applications of this 

 method to the analysis of solutions of dextrose, 

 maltose, lactose and sucrose are given, with com- 

 parisons of the results obtained by direct weigh- 

 ing of the reduced copper. 



The continuous sampling of sugar liquors: W. 

 L. Jordan. 



Preparation of galactose: E. P. Clark. 



The manufacturing of high purity crystalline 

 anhydrous dextrose: C. E. G. PoTST. 



Charles L. Parsons, 



Secretary 



