SEMI-TROPICAL CROPS. 99 



it, until the pure white starch only remains in a mass at 

 the bottom. This starch while wet is liable to ferment, and 

 the tibry matter separated from it is still more liable to 

 fermentation. Cool weather (not hotter than 70deg. in the 

 shade during the day) is desirable at the time of manufac- 

 turing. Weather of the requisite description is usual 

 during May, June, and July, during which season the 

 arrowroot is at its best stage for manufacturing. After 

 being stirred until perfectly clean a simple process, owing 

 to the weight of the starch always bringing it quickly to 

 the bottom of the vessel the starch is spread out in the 

 sun or in dry rooms upon cloth, and freed from the last 

 trace of moisture as rapidly as possible. When perfectly 

 dry, it keeps in bags, boxes, &c., for years, and is esteemed 

 as a valuable food material for the sick and healthy. 



The Australian Process. Machinery of very ingenious 

 construction has been brought to bear upon the manufac- 

 ture of this article, the cost of production being reduced in 

 proportion, while the quality is improved, as it is scarcely 

 handled from the time of leaving the field. The Messrs. 

 Grimes (Queensland) are famous for this article, their 

 arrowroot being extensively used in the colonies, in 

 England, and other countries. Instead of the laborious 

 and doubtful process of hand washing and grinding, which 

 is still the ordinary way of manufacturing this article in 

 the Indies, Cape, and other places, Australian arrowroot is 

 barely handled from first to last. The roots are shovelled 

 into long troughs, through which run continuous streams 

 of water. There is a screw in each trough with flanges, 

 which turn, roll and push the roots about, and keeps 

 gradually working them towards the upper end all the 

 time. They are perfectly clean by the time they arrive 

 there, and are pitched (by the flanges on the screws) in 

 ones, twos, and threes upon an endless chain which lifts 

 them some fourteen or fifteen feet and discharges them 

 into the hopper of a grinding machine. Here they are 

 reduced to pulp, which pulp by means of a stream of water 

 is discharged into perforated revolving drums, where it is 

 knocked about, beaten, and washed, all to separate the 

 starch from the coarser particles. The starch, as driven 



