534 



The other machine is called an elasto-durometer, and it is used 

 for determining the elasticity of a sample of rubber and also its 

 hardness and flexibility. The elasticity is determined by the fall of a 

 ball of chilled steel, upon a sample of the rubber. The height to 

 which the ball rebounds determines the elasticity. The apparatus 

 can be used for stone, metal, wood, leather, or any other substance 

 assuming that it can be laid flat. It can also be used to measure the 

 hardness of the sample by the aid of a steel needle which is pushed 

 slowly into the sample; by measuring the depth in millimetres into 

 which, with a given pressure, it penetrates, a certain method of 

 measuring the hardness of the rubber may be obtained. — Ed. 



PLANTING DISTANCES. 



The manager of the Bukit Rajah Estate reports that the best 

 results have been obtained in tapping from trees 27 feet by 27 feet. 

 In crowded fields the bark does not renew so thickly, and the trees 

 do not yield so much latex. Trees at Sungei Binjai planted wide 

 yielded 4 lbs. each, working out to 300 lbs. per acre. — Ed. 



A LARGE FICUS ELASTICA. 



A beautiful photograph of a very large Ficus elastic a growing in 

 forests at Tapanuly, Sumatra, is given in the Bulletin de 1' Association 

 des planteurs de Caoutchouc, Aug. 1909, p 120. The height is said to 

 be about 80 metres and it takes 36 men to surround it with their arms 

 outstretched. Its age is estimated at a hundred years. The tree is 

 growing in dense forest, and has apparently started as a seedling on 

 some forest tree at a great height from the ground. It gives a very 

 good idea of the natural growth of the plant. — Ed. 



DATE OF TAPPING IN BRAZIL. 



According to the French Bulletin above quoted, the period of 

 tapping in the Amazon seems somewhat irregular. In the districts 

 of the furthest affluents of the big river, say from the Peru border, 

 tapping commences in May, but in other parts of the State of 

 Amazon as later in July and August. The trees flower from July to 

 September, that is to say, towards the middle of the tapping season. 



Full and accurate statistics of this are still required. — Ed. 



RUBBER IN SOUTHERN INDIA. 



The subject of rubber planting came up at the meeting of the 

 United Planters Association of Southern India and Mr. T. C. Parker, 

 of Travancore, gave some information on the subject. The industry 

 was in its infancy, but there were no less than 20,000 acres under rub- 

 ber in Travancore and Cochin. They had commenced tapping and 

 got the full price for the rubber. Besides this area there were 

 4,000 acres in Coorg, 2,000 in the Nilghiris, 2,000 in Anamallays, 250 

 in Shevaroy and 2,000 in Malabar. — Ed. 



