utilization of the Sweet Potato 41 



65.0 and 69.0 per cent and it seems that any consider- 

 able increase of this percentage is accompanied by a 

 corresponding decrease in the starch content — the per- 

 centage of starch being about as many per cent below 

 the average as the water content is above the average. 

 There are three striking examples of this, — the Polo, 

 the Arkansas Beauty and the Yellow Nansemond; all 

 of these varieties containing over 72 per cent water 

 and below 15 per cent starch." 



White-fleshed varieties would probably be better 

 suited to commercial starch manufacture, since yellow 

 kinds might discolor the starch. It is possible that with 

 care in selection, the starch-content of specific varieties 

 could be increased. This possibility and other phases 

 of starch manufacture from the sweet potato offer a 

 wide field of study for the scientific investigator. 



Alcohol manufacture. 



When a solution of sugar is fermented by mixing 

 with a certain kind of yeast (Mycoderma cervisiae) and 

 kept at a certain required temperature until carbon diox- 

 ide ceases to be given off, there is formed the familiar 

 substance known as alcohol. The sugars necessary for 

 the fermentation of alcohol may be obtained from a 

 large number of possible sources. In the commercial 

 manufacture of this product, no cheaper means of pro- 

 duction has been found than by making use of the 

 fermentable saccharine matter contained in such crops 

 as rye, barley, wheat and other grains, A number of 

 fruit juices and vegetables may be made to yield alco- 

 hol by fermenting. In addition to about 18 per cent 

 starch which is capable of fermentation by first con- 



