33° 
August 1 2th, 1911. 
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 71. It was medium coloured, unsmoked sheet, 
approximately one-eighth inch in thickness and measuring about 
24 ins bv 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. 
Name of 
Sample. 
Glenealy 
Fine Para 
Elasticity and Recovery. 
Permanent set 
Pull after 5 after 5 
Minutes. Minutes’ rest 
21 1 /2 lb- 10 
1 7 lb. 8 
Break. Extension. Pull. 
64 lb. 8% ins. 25 lb. 
58 lb. 9 1 / 2 ins. 1914 lb. 
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 $y 2 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 [.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 palembanica ) 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 poi- 
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 ot the 
mangle being of wood. The sheets are dried in the factory for forty- 
