SUGAR OF LEAD 



951 



derably, a small bit of butter or fat is thrown into it. After the molasses has been 

 drained from the concreted loaves, the sugar is not at all deliquescent, like equally 

 brown sugar from the cane. Maple-sugar is in taste equally agreeable with cane-sugar, 

 and it sweetens as well. When refined it is equally fair with the loaf-sugar of Europe. 



The period during which the trees discharge their juices is limited to about six 

 weeks. Towards the end of the flow, it is less abundant, less saccharine, and more 

 difficult to be crystallised. 



The total production of maple-sugar has been estimated at 45 millions of pounds. 



Potato-sugar. The manufacture of sugar from starch derived from potatoes, from 

 woody matter, and from rags, can be effected by treating them with sulphuric acid and 

 heat ; but the process, interesting though it is, is rarely if ever adopted at present, as 

 the sugar is inferior in quality to that obtained from the cane, and is dearer in price. 



The specific gravity of cane andbeet-root sugar is 1'577, not 1'6065 as given by Ber- 

 zolius and others ; that of starch-sugar, in crystalline tufts, is 1 '39, or perhaps 1 '40, as 

 it A r aries a little with its state of dryness. At T342 syrup of the cane contains seventy 

 per cent, of sugar ; at the same density syrup of starch-sugar contains seventy-five 

 and a half per cent, of concrete matter, dried at 260 Fahr., and, therefore, freed 

 from the ten per cent, of water, which it contains in the granular state. Thus, another 

 distinction is obtained between the two sugars in the relative densities of their solu- 

 tions, at like saccharine contents, per cent. 



One of the most important considerations for a sugar-refiner is to furnish himself 

 amply with bone-charcoal of the best quality, and to devote unsparing attention to the 

 process of revivification. The theory of the action of bone-charcoal upon solutions of 

 raw sugar and other coloured liquids need not be discussed here. See CHARCOAL. 



The following Table contains the average results of many analyses made by Dr. 

 Wallace of Glasgow, of several kinds of raw sugar as imported into Greenock and 

 Glasgow, and of the different products of a Greenock sugar-house : 



Sugar Imported in 1873 : 



Kenned or sugar equal in quality, 

 and sugar-candy 

 Unrefined sugar 



Total unrefined of all kinds 



Class 



1st 

 2nd 

 3rd 

 4th 



Cwts. 



2,273,490 

 810,934 

 3,871,492 

 3,913,725 

 5,654,177 



Value 





 3,847,271 



Duty 

 d. 



per cwt. 

 2 10 

 28,, 

 2 5 







. 14,241,328 17,066,026 



Cwts. & 



Glucose, liquid or vegetable syrup . 36,306 43,373 



Molasses 520,315 245,766 



Sugar Imported in 1874 : 



Refined and Candy 

 Unrefined 

 Molasses . 



Cwts. 



2,617,861 



14,216,728 



339,352 



Value 







4,098,638 



15,901,046 



181,544 



Export of sugar, refined and candy, in 1874 : 



930,729 cwts. ; Value, 1,227,1642. 



SUGAR OP IiEAB, properly Acetate of Lead (Acetate dc plomb ; Set de Satumc, 

 Fr. ; Essigsaures Ttttioxi/d, Bldsuclccr, Ger.j, is prepared by dissolving pure litharge, 



