CANE SUGAR. 



With this method with sugars and juices a filtrate is obtained as .much 

 decolourized as by the use of basic lead acetate. Waste molasses cannot be 

 satisfactorily observed in greater than '25 normal solution. 



Normal weights of sugars require from -5 to 1 cc. of a saturated solution 

 of alum, and molasses in *25 normal weight, from 2 cc. to 3 cc. 



3. Basic Acetate of Lead has formed the most general clarificant of sugars. 

 It is used by adding a concentrated solution to the solution of sugar under 

 analysis. For 26 grms. of refining sugars from *1 to 1 cc. of lead acetate 

 solution, sp. gr. 1'25, are necessary; for the same quantity of molasses up to 

 15 cc., and for 100 cc. of juice up to 6 cc. An excess of lead acetate must 

 not be used. The material is thus prepared : 264 grms. litharge are digested 

 with 440 grms. neutral acetate of lead until dissolved and made up to 

 2000 cc. 



4. Neutral Acetate of Lead is used precisely as the basic acetate, but its 

 use is limited to such products as are light-coloured. 



5. Calcium Hypochlorite is used by Zamaron 2 in conjunction with neutral 

 acetate of lead. 625 grms. of calcium hypochlorite are shaken with 1000 cc. 

 of water, and the filtered solution, which should mark 1 8- 20 Beaume, pre- 

 served for use. Pellet uses 20 cc. of this in conjunction with neutral lead 

 acetate to decolourize 4 grms. of molasses. 



6. Dry Basic Acetate of Lead. This material was introduced by Home 3 

 to counteract certain errors occasioned by the use of a solution of lead acetate. 

 The dry acetate, together with a little sand, is added to the solution of sugar 

 after it has been made up to definite volume. For 26 grms. of sugar about 

 0-5 grm. of this material is required. 



7. Charcoal. Bone charcoal added to sugar solutions exercises a powerful 

 decolourizing effect, but, as it at the same time absorbs an appreciable quantity 

 of sugar, it is little used. It has been recommended to filter the sugar 

 solution through charcoal and to collect separately the later runnings after the 

 charcoal has absorbed all the sugar that it is capable of doing. 



Basic Nitrate of Lead is recommended for use by Herles. Two solutions 

 are used: a. 2000 cc. water and 90 grms. caustic soda; b. 2000 cc. water 

 and 1000 grins, lead nitrate. The lead solution is added to the alkali 

 immediately before use in the proportion of 1 of lead to 1*0 to Tl of alkali. 

 "With this solution [it is stated that the readings are not affected by an 

 excess and that lead does not pass into solution. It has not come into any 

 general use. 



8. Mercuric Compounds exercise an effect similar to that of lead with 

 the distinction that they precipitate amides from solution. They are not in 

 general use in sugar analysis, but very recently Andersen 4 has recommended 

 for use as a clarificant the following solution : 220 grms. HgO, dissolved in 

 160 cc. HN0 3 , sp. gr. T39, and made up to 1000 cc. with the addition of 



448 



