102 



caoutchouc might be collected iu one-fourth the time, and at far less 

 cost of labour." 



The fresh milk exhales an odour of ammonia, and if it has to be car- 

 ried to any distance 3 per cent, oi liquid ammonia is added to keep it 

 unchanged, but it is much better to coagulate the rubber on the day of 

 collection, and so prevent any danger of decomposition which results in 

 impurity of the rubber, and consequently a low price in the market. 



Yield. — Each tree is said to give 2 ounces of milk in a day, and the 

 milk yields from 30 to 50 per cent, of rubber. 



Dr. Trim en states in his Report of the Eoyal Botanic Gardens for 1893 : — 

 " Though I have expressed the opinion that this is a cultivation more 

 suited to a Government Department than to private planters, yet if the 

 cultivator can afford to wait for about twelve years, there is little doubt 

 of a profitable return. After the trees are once in full bearing they are 

 said in Brazil to continue to yield for a period of 75-100 years." 



The growth of a tree in the Henaratgoda Garden in Ceylcn, a wet 

 district, has been at the following rate, the measurement being taken 

 at 3 feet from the ground : — 



Age in years. Circumference. 



feet inches. 



4 



1 



4 



5 



1 



9 



6 



2 



11 



7 



2 



6 



8 



3 







9 



3 



7 



10 



4 



1 



11 



4 





12 



5 







13 



5 



5 



16 



6 



1 



17 



6 



7J 



In the Jamaica Gardens the growth has been exceedingly slow, but 

 in other localities in the island, doubtless the increase would be as great 

 as in Ceylon. 



Methods of preparing the Rubber. — Mr. Cross gives the following 

 details of the preparations of the Para rubber : — 



1 ' The collectors of the region I visited, resorted with their milk to a 

 large shed situated on the bank of the river Guama. Here were 

 various species of palm nuts, representing Attalea excelsa and Euterpe 

 edulis, stored in heaps, and several jars for the preparation of rubber. 

 These jars were 18 inches high and the bottoms were broken out. At 

 the base they were 7 inches in diameter, bulging out in the middle to 

 1 2 inches, and were narrowed at the mouth to a breadth of 2 inches. 

 Each person wrought on his own account, and so small jars were em- 

 ployed, but where a number of men are collecting for one master much 

 larger jars are in use. The milk, on being put into a large flat earthen 

 vessel, is put down on the floor in a convenient place. Adjacent thereto 

 the jar is sat on three small stones, which raises it to 1£ inches above 

 the floor. The narrow space beteen the base of the jar and the floor 

 allows the air to enter, which causes a current of smoke to ascend with 

 remarkable regularity and force. When the fire commences to burn 



