(i3 2 ) 



3014. Potato starch. — The starch extracted from the preceding. 



3015. Another sample of the same. From the New York College of Pharmacy. 



3016. Klow kow Nieu starch. — The starch of an undetermined plant of Siam. 



Sugars 



Sugars are formed by plants as a stage in the manufacture 

 of carbohydrate nutrients, and again when the carbo- 

 hydrate is used by the plant as food, as explained in our 

 account of starch. Although many varieties of sugar are 

 recognized, they all fall into two great classes, cane-sugar 

 and glucose. Cane-sugar occurs mostly in stems and roots, 

 glucose in fruits. Glucose is cheaper than cane-sugar and 

 if pure, is more healthful for human use, but the commercial 

 article is very apt to be impure. Glucose is mostly manu- 

 factured from corn. Cane-sugar is mostly manufactured 

 from sugar-cane, sugar beets and sorghum cane. 



3017. Pine sugar or manna. — A sugar that sometimes exudes naturally from the 



leaves of the great silver fir {Abies grandis Lindl.) (Pinaceae — Pine Family), 

 a native of Montana, Oregon, and British Columbia. Presented by 

 Franz Boas, in 1914. 



3018. Picture of a sugar-cane plantation. 



3019. Sugar-cane. — The stems of Saccharum officinarum L. {Gramineae — Grass 



Family). Native of eastern Asia and cultivated in all tropical and sub- 

 tropical regions. Collected by J. K. Small in southern Florida in 1904. 

 This is the principal source of cane sugar, which is obtained by squeezing 

 out the juice by passing the cane between rollers, and evaporating it down 

 by boiling, or by creating a vacuum in the container in which it is placed. 

 When partly boiled down, so as to become a thick liquid, it is called molasses. 

 After carrying the boiling as far as practicable, it is allowed to stand, when 

 the sugar forms at the bottom and molasses rises to the top. The molasses 

 is then poured off and the sugar is allowed to drain, the drainings being used 

 as syrup. A further amount of syrup may be removed by the use of a cen- 

 trifugal machine. The sugar so resulting is called "raw" or "unrefined" 

 sugar and is valued according to the percentage of pure crystallizable 

 sugar that it contains. Great quantities are consumed in this state, but 

 for ordinary use, it is subjected to various methods and degrees of refining 

 and decolorizing, and is graded and valued according to the degree to 

 which such refining is carried. 

 Numbers 3020-3069 constitute a series of raw and refined sugars representing 

 various standard grades. Unless otherwise specified, they were presented 

 by the American Sugar Refining Company. 



3020. Pinoche. — An unrefined cane sugar made and used in Mexico. Acquired 



at Torres, Sonora, Mexico, in 1902 by D. T. MacDougal. 



3021. Guatemala muscovado. — Unrefined sugar produced in Guatemala. 



