90 
horhans the wood proper,—in the bark (in the usual sense of the 
word), the leaves os petioles, and pericarp; any of these, snapped 
across, and the parts drawn asunder, exhibit the silvery sheen of 
innumerable feeds of this gum 
His account continues: “The morphological relations and 
general histology of the cells which give rise to the substance, 
we hope to have the seinen of describing from specimens in 
h Dr. He 
fluid or living, which, throug enry’s kind offices, there is 
probability we may soon receiv ve.’ 
Phe se the promised specimens arrived Mr. (now Prof. 
. EK. Weiss undertook the examination of them, and from the 
cnt of his investigations, published in the Transactions of the 
innean Society — 2, Botany, iii., p. 243), the following 
sentences are dra 
“The threads of “hatin consist of caoutchoue, for they are 
nsoluble in alcohol, acids and alkalis, though they, become soft 
het treated with ammonia. They dissolve in chloroform and 
turpentine, and swell up in ether. When heated they melt, and 
they burn with the a poe smell of burning ber. 
them: t e other chiefly of bits of bark ea no doubt, smaller 
pieces of the threads. From both parts chloroform will dissolve 
out caoutchouc, a larger amount antitally from the portion which 
consists chiefly of the threads. Thus, a sample of the threads and 
bark weighing 443 mg. gave as_ mich as seg ng. 0 of ae 
ly 6m 
Taking the two quantities together, the yield ae aoutchouc was 
at at independently by Prof. F. W. Oliver with aides 
sam 
“The threads are clear and homogeneous, and the only impurity 
in the chloroform extract seems to be a little resin, which can be 
washed out with aleohol. 
“Whether the bark can be made use of commercially I must 
leave to those who are more experienced in technical ters 
cd 
ety of Hucommia, which resembles in a pearan 
that ¢ of gy some is especially rich in these oo 
