BEET SUGAR. The manufacture of sugar from beet roots is a comparatively modern in dustry, having its inception in the investiga tions of Alargraff. who in 1747 announced to the Merlin Academy of Sciences the analyses of sev eral sugar-containing plants and predicted that the sugar beet (q.v.1, being the most saccharine of the plants examined, would become the basis of a great industry. Nearly half a century later the problem was solved by a pupil of :\largrafil, Achard, who made a considerable quantity of beet sugar and announced his methods to the Berlin Academy of Sciences and to the Institute of France in 1797 and 1799. respectively. In Germany several beet-sugar factories were built within the next decade, and beginning with 1810 the industry, being stimulated by governmental aid in both countries, developed steadily. Aston ishing improvements have been wrought in all branches. The percentage of sugar in the roots has been increased by selection from less than 7 per cent. at the beginning to an average in 1900 exceeding 14 per cent. and a maximum of more than 20 per cent.; the quality of the roots, the yield in tons per acre, and the improved proc esses of manufacture, which according to German statistics have reduced the weight of roots necessary to yield a pound of sugar from IS pounds in 1837 to 7.02 pounds in 1899, have combined to make the industry profitable both in Europe. with its cheap labor, and in America, with its cheap lands.
In the manufacture of beet sugar the roots, already trimmed of leaves, are conveyed by water in little canals which extend through the bottoms of the V-shaped storage sheds, to the washing machine, where every particle of soil is removed by revolving brushes, the roots con stantly progressing against a current of water toward the automatic machine. After the weight has been recorded the roots go to the slicer. Here they are cut by corrugated knives into little V-shaped slices (cossettes) that drop into large iron tanks (cells), a series of 12 to 14 of which constitute a 'diffusion battery,' so called because the sugar is removed from the cossettes by water into which the sugar diffuses and which passes by a complicated system of pipes and valves through all the charged cells of the series, always from the filled cell, containing nearly exhausted cossettes, to the most recently filled. thus removing the largest possible quantity
of sugar with the smallest quantity of water. One of the two uncharged cells is always being filled with fresh eossettes, the other being emptied, its cossettes containing less than 0.5 per cent. of sugar. Thus the process is continuous. The exhausted cossettes, which are used as stock fond, are pressed to remove the excess of water and in some cases are dried to enhance their transporting and storing qualities.
When the 'diffusion juice' leaves the battery the coarse particles of beet pulp are filtered out and from two to three pounds of lime added for each hundred pounds of beets used. Carbon diox ide is then forced through the liquid to precipi tate the lime, together with certain impurities, after the removal of which the operations of lim ing, carbonizing, and filtering are repeated. If the final product is to be a white sugar, the clear juice is then bleached with sulphurous acid and again filtered. The subsequent treatment cor responds more or less closely with that employed in the factories using sugar-cane.
The United States Department of Agriculture and various experiment stations, by means of special appropriations, have assisted greatly in the development of the beet-sugar industry, which is established on a firm footing in Amer ica. Especially since I S97 (see table) has the growth been rapid, the capital invested being, in 1900, more than $25,000,000.