12 
some of the West India Islands. Mr. Biffen has therefore had 
. a favourable opportunity for becoming acquainted E the con- 
ditions under which rubber is at present prepared, 
vigi to ae scientific methods for the porca of 
the ind 
While pde during ie latter part of 1896 in studying the 
functions of latex, my ention was frequently called to its 
spontaneous coagulation rene in contact with the air. 
e Bary describes the phenomenon as follows* :—“ As soon as 
butt comes in contact with the air, and still epe quiekly on 
treatment with water, aleohol, ether, or aci ids, ula appear in 
P 
and iu: e further inyontigeti 
nation of the subject was enu commenced with 
were continued, together with other researches on a larger scale, 
in Mexico, Brazil, and the West Indian Islands. 
Ru bons -yielding plants, which always have laticiferous cells, 
were for the most part chosen on account of the ease with which 
large quantities - — could be obtained, and because the various 
processes used i e preparation of crade rubber seemed likely 
to throw some light upon the subject. 
A microscopic examination of any of these scis shows that 
its milky appearance is due to the presence of innumerable small 
granules of caoutchouc, which in themselves a “soft and sticky, 
for they readily cohere to form a small mass of rubber if the 
cover-glass i is lightly d on the slide. 
Some of the — employed to prepare this rubber may be 
described here 
In the EE of = rubber, a thin layer of the latex of 
Hevea brasiliensis (Muell ae) or other species of Hevea, is 
exposed to the action of the smoke of burning * urucuri’ ' nuts 
(Attalea excelsa, Mart.) ; sae tation is immediately brought 
about, resulting in the formation of a we eoe mass of rubber, 
which on ing becomes tough and elas 
same process is now being a Hei with good results to the 
laziovii 
The 
preparation of Ceará rubber from the latex of Manihot G 
(Muell. Arg.). 
* De Bary, Comp. Anat. of uas i Peck pe IHE 
