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The World's Commercial Products 



quickly settles to the bottom when the supernatant water is drawn off. It is again beaten 

 into a cream with water by mechanical stirrers, and when it has once more settled and the 

 water has been removed, it is found that the upper layers are somewhat, discoloured, while the 

 main mass of the starch below is of a pure white colour. The pure starch is ready for the 

 drying tables while the discoloured layers are further cleaned by repeated processes of stirring 

 and allowing to settle." 



In the more modern factories the drying is performed in kilns provided with steam heaters. 

 It is important that the wet starch should not be subjected to the full force of the heat at 

 once, or the grains would be converted into paste and rendered unfit for the market. The kilns 

 are, therefore, built with four or five floors made of narrow wooden slats fixed a short distance 

 apart, and the steam pipes are laid at the bottom of the kiln. The blocks of wet starch are 



By permission of Messrs. Cadbury Bros. 

 YOUNG CULTIVATION, WITH CATCH CROP OF BANANAS, CASSAVA, AND TANIA, TRINIDAD 



shovelled on to the uppermost floor, which is the coolest part of the kiln, and the drying com- 

 mences. After a little while the mass is raked over, and the drier portions of the starch auto- 

 matically fall between the slats on to the next floor below, where they are subjected to a higher 

 temperature. The processes repeated on each floor until the whole of the starch has reached 

 the bottom of the kiln, which is filled and emptied twice in every twenty-four hours. The dried 

 starch is finally raked into a trough and transported to warehouses where it is stored on 

 the floors, the piles resembling huge snowdrifts. During this storage the starch becomes 

 uniformly dry, and is finally packed in barrels. 



Potato starch is very largely employed in the textile industries, where it is used for three 

 distinct purposes : in the first place, it is used as a sizing for the warp yarn before it is woven, 

 the loose ends of the fibres composing the yarn being cemented down, resulting in a smooth 

 strong thread ; secondly, the starch paste is used to give a finish to the goods after they have 

 been woven ; and, thirdly, in the form of dextrin, potato starch is used to a certain extent 

 as a thickener or vehicle for applying colours to the fabric. 



