i88 THE RUBBER TREE BOOK 



should leave the factory except through the door leading to the 

 drying-shed and packing-house. Proper regulations of this 

 sort assist in keeping down petty pilferings of the manufactured 

 rubber, of which far more often goes on than managers are 

 aware of. In Ceylon, the Federated Malay States and Sumatra 

 there are nearly always dishonest dealers in the villages who 

 are ready to bribe the coolies to steal rubber if carelessness 

 affords opportunities. 



The rough macerating-mill should be nearest the door at 

 which the latex enters. This is for two reasons. In the first 

 place, latex, lump-rubber, scrap and bark-shavings are always 

 treated first in this mill, and carriage is saved by having it at 

 this end of the factory, which is also where the straining and 

 coagulating of the latex should be done. In the second place, 

 this rough macerator, with its deep-grooved rollers, is the mill 

 in which scrap and bark-shavings are worked up, and there is 

 always a lot of dirt in these which is best kept away from the 

 better-quality rubber. Dirty rubber such as these grades 

 should always be worked up at the close of the day's pro- 

 ceedings, on account of the amount of dirt brought into the 

 factory embedded in such rubber and thrown out by the rollers 

 of the macerator when the springy masses of rubber are 

 stretched springing out in passing between the rollers revolv- 

 ing at different speeds. Some planters, for this reason, prefer 

 to keep the macerator quite apart from the other mills, either 

 boarded off or outside the factory, but such a course is neither 

 necessary nor yet convenient. 



When it is proposed to make sheets of crepe-rubber the 

 lumps of coagulated rubber are first treated in the macerating- 

 mill. This mill converts the unshapely lumps of coagulated 

 latex into thick, rough sheets. In the course of the rolling 

 between the rough-cut, grooved-pattern rollers revolving at 

 different speeds (usually a gearing of 18 teeth in one roller and 

 22 teeth on the other or 17 teeth to 21 teeth), there is a tearing 

 and shredding of the mass, on which water is being constantly 

 poured from a pipe over the rollers. This washing and shred- 

 ding removes not only dirt but much of the protein and non- 

 rubber matter originally contained in the latex and gradually 

 transforms the cheesy mass into rough sheets of wet rubber. 

 These protein and starchy substances, if left in the rubber, 



