60 ELEMENTS OF APPLIED MICROSCOPY. 
rated with comparative ease, and is the cheapest of all 
the starches; but in wheat and rice the union between 
carbohydrates and albuminoid matter is so close as to 
introduce serious difficulties. In the latter case it is nec- 
essary to use strong alkalies; and with wheat the same 
end has generally been obtained by moistening and thus 
swelling the grain, bruising it and then allowing it to 
stand and ferment until the nitrogenous substance has 
been partly rotted and disintegrated. The unfortunate 
feature of this method lies in the necessary loss of the 
glutinous constituents of the grain which possess high 
nutritive value; in certain processes the fermentation is 
omitted and gluten and bran are obtained as by-products. 
The cost of the various starches depends both on the 
difficulty of separation and on the value of the raw ma- 
terials. Its range is indicated by the following list of 
prices compiled by Dr. H. W. Wiley for the year 1899: 
MEAN WHOLESALE PRICE OF VARIOUS STARCHES. 
Cents per pound. 
Comic: aiitaotes ees 1.46-1.61 
Sago flour.................00. 3.73-3.98 
POtatOvcgciein 4s ssesedes . 4.21-4.57 
Tapioca flour..........00 2.02. 4.63-4.96 
Wheat: :c5saueuey deers Sees 509-9 .00 
Rice’ wives ee awed Ailes & 7 .50-9.00 
3. Commercial Uses of Starch.— Wheat-starch was 
well known to the ancient Greeks and Egyptians, having 
been first produced, it is said, in Chios, but it was not 
