264 



SCIENCE 



[N. S. Vol. LIII. No. 1368 



Befining raw sugars without ionelilaoh: 0. E. 

 CoATBS. Eaw sugars from the tropics have been 

 refined off and on in Louisiana for a number of 

 years. This was profitable on occasions when the 

 margin between raws and granulated was high. 

 During the past two years this margin has been so 

 high as to offer exceptional profits to the refiner. 

 A number of Louisiana sugar houses purchased raw 

 sugars during the last six months and refined them 

 by several different methods: Phosphoric acid and 

 lime; sulphur-dioxide and lime; fiJ tercel alone; ac- 

 tivated wood charcoals. At the beginning of the 

 campaign, the yields were several per cent, below 

 those obtained in the standard bone black refinery 

 process, but as the season went on this difference 

 was diminished until at the present time the yield 

 is about one per cent, short of good refinery prac- 

 tise. The yields by the various methods are nearly 

 the same. There is no reason why melting trop- 

 ical raw sugars can not become a part of the rou- 

 tine practise in both cane and beet sugar houses. 

 The quality of the sugars obtained is excellent 

 and in the case of the activated charcoals the 

 sugars were beyond any criticism of any sort. 



Recent advances in defecation: W. D. Horne. 

 The Dorr Clarifier has been devised to remove the 

 insoluble impurities from cane juice. Hot limed 

 juice continuously enters the central well of the 

 superimposed settling compartment equipped with 

 slowly revolving scraper mechanisms. Clear juice 

 flows from the periphery, and a thick mud is con- 

 stantly withdrawn from the bottom. The William- 

 Bon Clarifier aerates a warm defecated raw sugar 

 solution and then passes it through a long shallow 

 heating tank provided with suitable baffles, caus- 

 ing all insoluble matters to rise in a scum, which 

 is mechanically skimmed off, while clear liquor is 

 continuously syphoned out below. 



Comparative analysis of refined sugars: Fred- 

 erick Bates and associates at the Biireau of 

 Standards. A resume was given of the results of 

 an elaborate and exhaustive study of about 250 

 sam/ples of refined sugars produced in the United 

 States. One of the principal objects of this work 

 was to determine the feasibility of preparing accu- 

 rate specifications and definitions of the refined 

 sugars. The work included the determination of 

 the direct polarization, invert sugar, moisture and 

 ash. The acidity and alkalinity were determined 

 by developing a new method, using the hydrogen 

 ion concentration with gratifying results. The 

 average acidity and alkalinity was found to be 



small and indications are that the departure from 

 neutral is a powerful factor in determining the 

 properties of the sugar. In addition, the sugars 

 were screened ,to determine average size of grain. 

 A preliminary report was given on the importance 

 of improving and applying the so-caUed candy 

 test to refined sugars. 



A graphic method for estimating reducing sugars 

 in presence of sucrose: C. A. Browne. The slight 

 reducing action of sucrose upon Pehling's copper 

 solution introduces a considerable error in deter- 

 mining reducing sugars in presence of large 

 amounts of sucrose. The author proposes a general 

 graphic method which consists of a chart contain- 

 ing the reduction curves for dextrose in amounts 

 from to 250 mgs. in presence of sucrose from 

 to 5gs. The correct amount of dextrose, corre- 

 sponding to the amount found, is determined by 

 finding the curve which passes through the inter- 

 section of the coordinates for grams sucrose pres- 

 ent (as determined by Clerget) and mgs. dextrose 

 found. The starting point of this curve on the 

 base line indicates the correct amount of dextrose. 



Commercial production of d-Mannite: W. B. 

 Newkirk and C. F. Snybeb. At the request of 

 the Army, the manufacture on a commercial scale 

 of d-Mannite from manna was undertaken. The 

 crude manna was dissolved in water in a melter 

 heated by steam coils. The liquor was 17° Brix. 

 It was heated to boiling and defecated. Three 

 methods of defecation were employed. Method 1 : 

 .005 per cent, phosphoric acid added to hot liquor 

 and let stand for thirty minutes, neutralized with 

 lime, allowed to settle and the clear liquid de- 

 canted and filtered. The filtered liquor was boiled 

 in open pan to 30° Brix (hot), placed in tank and 

 crystallized. The crystals were separated in a 

 large centrifugal. Method II. : The raw liquor was 

 treated with 0.10 per cent. Kieselghur and filtered 

 and the filtrate concentrated as above. Method 

 III.: The raw liquor was treated with 0.5 per cent, 

 commercial vegetable carbon and filtered and the 

 filtrate concentrated as above. Method I. was the 

 most satisfactory. The mother liquors from the 

 first crystallization were concentrated to 40° Brix 

 and allowed to crystallize; the mother liquors from 

 the second crystallization were concentrated at 

 60° Brix and a third crop of crystals obtained. 

 The mother liquor from the third crystallization 

 was concentrated at 80° Brix and a fourth orop of 

 crystals obtained. The final mother liquors were 

 concentrated to 80° Brix and a fifth crop of 

 crystals obtained. A tabulation is given of the 



