2 
Fonnol ! the very coagulant preconised by Dr. C. 0. WEBER. 
When Doctors disagree &c. &c. I do not say this in disparage- 
ment of Dr. Webers’ statement; he is far too great an authority 
1 ; or me to dispute his statements, but his method has against it that 
it is open to the same objection as other chemical coagulations viz: 
that we do not yet know the behaviour of the product in its ulti- 
mate manufactured state. 
The fact is, the very nature of india-rubber in its pure state is 
so litttle known, the particular physical arrangement of molecules 
which gives it its tensility and the property of re-traction is so little 
understood : we have such dim notions of the way in which the 
various elements of the latex, which go to form the constituents of 
pure rubber, combine or separate in the act of coagulation, that we 
must be content, in the present state of our knowledge, yet awhile 
to tread the old beaten tracks of empirism. 
Take for instance, centrifugalisation of the latex. In aiming at 
producing a pure crude rubber, we strive, after all foreign impurities 
have been eliminated, to work out the destruction of the fermen- 
tescent elements or proteids ; well ! centrifugising does it, and 
what is the result? — a rubber which in the vulcanizing process loses 
its tenacity and vitality — a product inferior to that of coagulation 
by heat ! 
I will not linger on the “centrifugal” process. To obtain 7,000 
revolutions a minute — the speed required in the treatment of 
Hevea — a motor will be required — that disposes of the matter for 
the present at any rate. 
To resume this already too long letter, my invention is simply a 
mechanical and automatic adaptation of the Brazilian method. 
That method has stood the test of time ; it has answered all the 
requirements of manufacturers. It stands on proved merits, which 
cannot be said unreservedly, so far, of any other method of pre- 
paring rubber. 
The apparatus itself is extremely simple; one coolie can work it 
without effort ; it is light ; it requires no special installation and 
can be transported to the fields, if need be. 
E. MATHIEU. 
Singapore, 28th January , /903. 
PARA RUBBER TREES AT HIGH ELEVATIONS. 
In reply to an enquiry, whether Para rubber would be profitable 
if grown at an elevation of 1,600 feet to 1,800 feet, Mr. F. J. Hol- 
loway of Kepitigulla, Matale, Ceylon, writes to the Times of 
Ceylon : — I am now tapping some trees at about 1,600 feet, on a 
hillside, and am very pleased with the excellent results obtained. 
Trees at this elevation, although a good deal smaller than the ones 
of the same age at a lower elevation, are now being proved to 
yield better than those lower down. 
They only require one incision in the morning, and the cups are 
emptied at 11 a. m. and replaced under the same cut immediately, 
