Page:Illustrations of Indian Botany, Vol. 1.djvu/237

Rh kingdom, and if we may judge of others from what is known of the Pinney tree ( Calophyllum } the timber of some at least must be very valuable, but little seems yet known regarding it. Roxburgh generally so attentive to the uses and applications of the plants he describes is altogether silent on this head respecting Guttiferœ, contenting himself with the mention of several, the fruit of which is eatable, such as the well known Mangosteen ( Garcinia Mangosluna ) the Garcinia cowa, of Silhet and Malabar, the fruit of which is " eatable, though not palatable" the G. Kydiana, the fruit of which is " an exceedingly sharp but pleasant acid, and the aril or pulp, by far the most palatable part," and lastly, the Garcinia pedunculala" the fleshy part of the fruit, which covers the seed, and their proper juicy envelope or aril is in large quantity, of a firm texture, and of a very sharp pleasant acid taste. It is used by the natives in their curries and for acidulating water." As it retains its qualities when cut into slices and dried, he suggests, that it might be advantageously employed on long voyages as a substitute for lemons or limes. The pulp of the fruit of Garcinia paniculata he thinks more like that of the Mangosteen, than any thing else he can compare it to. The parched climate of this portion of India renders it unlikely that we shall ever succeed in introducing many of them here : Roxburgh tried in vain for 35 years to make the Mangosteen grow and be fruitful in Calcutta. The attempts made in the gardens of Courtallum have been more successful, for there two or three trees annually ripen their fruit, few in number it is true, but the trees are still young. Plants raised from seed saved from these trees were, I learned some time ago. thriving in Mr. Huxham's plantations in Malabar. From this source therefore, it seems not improbable, the tree will extend along that coast the climate of which appears congenial to the plant.

Of those producing Gamboge, Roxburgh particularly mentions two kinds, namely, Xanthochymus pictorius and Garcinia pictoria. The juice of the former differs so very widely in its qualities from good Gamboge, that it can never be expected to prove valuable as a pigment, until its chemical constitution is better known than it was to Roxburgh, and measures can be adopted to render it more manageable in the hands of the artist. This result the imperfect analysis of Dr. Christison seems to indicate, is most unlikely, since however well known, it does not possess the elements of Gamboge : a further confirmation of the opinion, expressed above, that it is not a genuine Guttifera. That of the latter is described as affording a bright coloured superior Gamboge when recent, but the colour liable soon to fade. The tree or trees, however, which produce the Siam or Chinese Gamboge of commerce is not yet known, though the result of late enquiries on the subject in Ceylon, leave scarcely a doubt, as to it or them being members of this family — neither is the kind of preparation known, which the finer kinds undergo to fit them for the European market. The account given of the course of this article to the European market is, that it is produced in Siam and carried thence to Singapore, whence it is imported into England by the China ships.

The best account we yet possess, so far as I am aware, of the qualities and composition of Gamboge is given in a paper by Professor Christison of Edinburgh, " On the sources and composition of Gamboge, with an examination of some analogous concrete juices" published in the second volume of Hooker's Companion to the Botanical Magazine, the whole of which article I should, had space permitted, have transferred to these pages, as being so much more generally read in this country than the work in which it originally appeared. Some extracts from this masterly memoir I shall however introduce, in the hope that they may lead to still further enquiry both in this country and in the eastern Archipelago, where the tree producing it, is most probably indigenous, and prove the means of putting us in possession of flowering specimens of the plant thereby enabling us to set at rest this long agitated question, viz., what is the tree that affords the Gamboge of commerce ? — one Ceylon tree, the one here figured under the name of Hebradendron Cambogeoides, has beep ascertained to produce a Gamboge, agreeing in nearly all respects with the best Siam Gamboge, whence it is presumed, and on good grounds, that a nearly allied, if not the identical, species is the one that produces the Gamboge of commerce, which it would appear from the enquiries of Dr. Christison is altogether derived from the eastward, none having as yet been exported from Ceylon for the English market.

Of the Ceylon tree, Dr. Graham, Professor of Botany in Edinburgh, has given a very interesting account in the same volume of the Companion to the Botanical Magazine, and shown that it is totally different from the Stalagmitis Cambogioides of Murray, the tree hitherto supposed, on most insufficient grounds, to be the source of this very valuable substance.