330 



August I2th, igii. 



Since writing on this subject on July 19th (Page 5). I have receiv- 

 ed permission to publish the details of the tests, made on the sample 

 of plantation sheet rubber then mentioned. 



The rubber came from the Glenealy Plantations, Ltd., Perak, 

 Federated Malay States, was exhibited on the British Malayan Stand 

 and numbered /I. It was medium coloured, unsmoked sheet, 

 approximately one-eighth inch in thickness and measuring about 

 24 ins. by 12 ins. It was even in texture, translucent, of a warm 

 brown colour and outwardly of good quality, though some of the 

 sheets were slightly spotted with mould. It was kindly tested by the 

 Continental Rubber Company, of New York, in the Exhibition ; at the 

 same time and under the same conditions as the samples mentioned 

 in my previous letter ; the figures being : — 



Breaking Strain. Elasticity and Recovery. 



Permanent set 



Name of Pull after 5 after 5 



Sample. Break. Extension. Pull. Minutes. Minutes' rest 

 Glenealy 641b. 8^ ins. 25 lb. 21^ lb. 10 



Fine Para 58 lb. 9^ ins. 191^ lb. 17 lb. 8 



It will be seen that the breaking strain is 6 lb. more than for fine 

 Para; this equals 10.35 per cent, greater strength. The resistance to 

 pull is more by sVi lb. and by 4V2 lb. after five minutes extension; 

 equal respectively to 28.20 per cent, and 26.47 per cent, greater resis- 

 tance to pull. As in the former case, fine Para has the slight advan- 

 tage of 1.56 per cent, in permanent set after five minutes extension 

 and five minutes rest. 



Mr. E. T. C. Garland has kindly supplied me with the following 

 details respecting the growing and preparation of this rubber. The 

 Glenealy Estate is situated near the Perak River at Parit, six miles 

 from Seputeh. Parit is about twenty miles, as the crow flies, from 

 the sea coast, and eighty-five, following the course of the Perak 

 river. The trees are twelve years old and under, planted experiment- 

 ally by the Government in avenues on sloping ground of gentle undu- 

 lation ; the avenues had Merbau {Afzelia palemhanica) trees planted 

 between them ; which Mr. Garland had cut out in 1906-7, at the same 

 time as the lalang was eradicated, and young rubber planted in place 

 of them. The field is forty acres in extent and only about 2,500 trees 

 are now being tapped, giving an estimated yield this year of 10 lb, 

 per tree. 



Acetic acid is used for coagulating, diluted with water to make 

 a 10 per cent, solution. The general basis of mixture being one fluid 

 drachm of dilute solution to one quart of latex; equal to .031 per 

 cent, of acid. It is added gradually to a large jar of latex, whilst the 

 contents are being stirred with a stick. The latex coagulates in por- 

 celain pans within two hours, and is finished off by a hand mangle 

 the same day. Absolute cleanliness is essential, and the only metal 

 the latex touches is the galvanised spouts on the trees, the rollers of the 

 mangle being of wood. The sheets are dried in the factory for forty- 



