144 
ANALYSES OF HEVEA LATEX. 
Messrs. Clayton, Beadle and Stevens have se nt ^ interesting 
naper on some Analyses of Hevea latex published in The Analyst 
L T a nuary 1911. One of the interesting points is the comparison of 
latex from the leaf stalks of the Para rubber tree with that of the 
trunks of trees four and ten years old. 
It is now many years since an attempt was made at the Botanic 
Gardens, Singapore, to extract latex from the leaf stalks of tketa 
rubber tree. M. Arnaud. the inventor of the extraction °f Gl jt 
percha Vom the leaves, was trying the same process on the leaf 
stalks and twigs of Hevea braziliemis and a large quantity of boughs 
tops etc , of Hevea was supplied to him. His process for extracting 
the Gutta percha from Dichopsis gutta leaves t0 ^‘“^y 
and twigs to powder and immerse them in water, the refuse e vent ^hy 
sank and the Gutta percha floated on the water whence it was skim- 
med off. He tried, as did I, this process on Hevea twigs and leaves 
but the only result was a dirty looking solution in which no rubb 
could be seen. 
M Arnaud got some more leaves and twigs and took them off to 
try again and some days later I met him, as I was driving out, waving 
triumphantly a piece of rubber in his hand. 
After trying many methods, he had succeeded in making the 
niece of rubber by rolling the twigs and petioles with a warmed 
wooden roller. The rubber adhered to the roller and was then 
peeled off. It was very tacky and soft, and owing to the abandonment 
of topping trees, which would have supplied material and the poo 
quamy of the rabber produced, the experiments were not carried 
further. 
Messrs. Clayton, Beadle and Stevens have been in™ s tigaflng the 
rubb-r from the leaf stalks of Para rubber, and say that the dried 
latex at first rather tacky but on keeping a month or two and 
passiim between steel rolls it is no longer adhesive and somewhat 
resembles a high class purified Guayule rubber, it is . pale mn cota nr 
but rather soft, and much weaker than rubber from the bark ot 
mature trees.” 
The authors give then the analysis of this rubber compared with 
that of four and ten years old. 
Dried latex 
from leaf stalks. 
From 4 year old. 
From 10 
year old. 
Acetone Extract (resin) ... 
Protein 
Ash 
Caoutchouc (by difference) 
7.12 
13.02 
I.19 
78.67 
4.06 
4.9O 
0.80 
90.24 
4 - 13 
5- 08 
i -75 
89.04 
