338 ILLUSTRATIONS OF THE BOTANY OF [Artocarpee. 
with an acrid principle. Many species yield tenacious juice, of which bird-lime is 
frequently made, as Artocarpus integrifolia and Lakoocha, Ficus indica and. religiosa ; 
also, F. Tsiela, Roxburghii, glomerata, and oppositifolia. From some of these an inferior 
kind of caoutchouc has been obtained; but in considerable quantities, and of a very 
good quality, from Dr. Roxburgh’s F. elastica, which he describes as being of the size 
of a mango-tree, or full-grown sycamore; the older trees yield a richer juice than 
the younger, from incisions cut in the bark all round the trunk from its base to 
the top. Of this milky juice, 500z. yielded 1530z. of the clean-washed caoutchouc. 
With the milk the natives pay the insid 2s of their vessels and baskets, so as to enable 
these to hold liquids: the caoutchouc furnishes them with candles and flambeaux. 
Dr. Roxburgh discovered many years ago that it was perfectly soluble in Cajeputi oil, 
rather an expensive medium,but sufficient to indicate the kind of menstruum of a 
cheaper nature which would dissolve it. The other plants made known by Dr. Roxburgh 
as secreting caoutchouc are, Urceola elastica, which yields in Penang the cee kind, 
oo edulis, and Melodinus monogynus (v. p. sdaneaace 
eas det. ) . = The 
* Since the above passage was in type, I have received specimens of the Caoutchouc of Fi s elastica, 
from Mr. G. Swinton, late Chief Secretary to the Bengal Government, who had it collected so long ago as 1826 
in Silhet, and sent it to Sir D. Brewster for experiment ; but it never attracted the notice of commercial men, 
either in India or England. Notwithstanding that Professor Seddon, at. the desire of the late Mr. D. Scott 
(so well known for his zealous endeavours to elicit the resources of the districts committed to his charge): 
sent it from Assam to a principal house of agency in Calcutta ; but was informed that ‘the article being unknown 
, in this (the Calcutta) market, we are sorry We fe can give you no idea of its value:” and this, in March 1828, 
when it was selling in London for two shillings a-pound. As Caoutchouc has now become an extensive 
article of commerce, and a Company has been formed in London called the London Caoutchouc Company, 
of which one of the objects is to encourage the collection of this substance in India, so that the home 
manufactures may not be dependent upon too limited a field of supply, it cannot but be highly gratifying to 
Mr. Swinton to have his early anticipations of its value so completely substantiated. This, the more so, as so few 
were found either here or in India, who perceiv d the importance or encouraged the prosecution of his exertions, 
to bring not only this, but many other Indian products into notice; several of which might by this time 
have become important articles of commerce. It is curious that Mr. Swinton should also have been the 
medium of communication with Mr, Scott, for announcing the fact of the Tea-plant being both indigenous 
and cultivated within our then newly-acquired territories in Assam. As the Caoutchouc was pronounced to 
be of no value, so the Tea was said to be only a Camellia; and as the former has come to be so desirable an 
article for a commercial body here ; so has the latter om e an object of solicitude even to the Indian Govern- 
ment: a scientific expedition, headed by Dr.Wallich, having been sent into Upper Assam to explore the Tea 
country, whose report the scientific world are anxiously expecting. 
I have been favoured with a letter from my friend, Professor Christison, of Edinburgh, who obtained 
specimens of the above East-India Caoutchouc, after it had been eight years in the country, and employed 
it in making a flexible tube for conveying coal-gas. Respecting it, he says ‘“ I can most decidedly state, that 
80 far as my trials go, it is a far better article than is commonly thought, and quite fit for many most 
ae seeciomical uses.” Since the arrival in London, from Mr. Swinton, of the specimens of this 
! they have been submitted to experiment by Mr. Sievier, the Sculptor, so well known for his 
numerous 5 experiments on, and important applications of, this substance. He pronounces the India-rubber 
from Silhet, though carelessly collected, and so long ago as eleven years since, to be equal in elasticity to the 
best 
