CHAPTER VII 



FACTORY WORK ON THE ESTATE 



General. 



THE latex, brought to the factory in tanks or buckets 

 as it is collected from the trees, contains as a rule from 

 30 to 40 per cent, of pure caoutchouc. The latter is 

 obtained in a state of considerable purity by the 

 successive processes of coagulation, washing and drying. 

 The method of preparing biscuit rubber by hand, as 

 practised during the earliest beginnings of the industry, 

 is now of little more than historical interest. It may 

 serve however to illustrate in their simplest form the 

 nature of the chief processes concerned. 



In this method the latex is first strained through 

 a brass or copper wire sieve of small gauge, and then 

 generally diluted with one or more times its own bulk of 

 water. The diluted latex is next agitated with a dilute 

 solution of acetic acid, containing about one volume of 

 pure acid for every 1000 volumes of pure latex. The 

 acidified latex is then poured into round shallow pans to 

 set. Coagulation begins almost immediately, but the 



