If, on the other hand, it be true, that all substances of which organised bodies are found to consist, must of necefsity have existed in that state before they entered into their composition, then it must follow as a necefsary consequence, that calcareous matter cannot be of animal origin, but must have existed in this globe before either animals or vegetables were formed, and that calcareous matter must not have been deposited in mighty masses here and there like the Alps, which extend for many hundred miles in length, and in some places for at least one hundred miles in breadth, and for the greatest part of the way more (nobody can say how much more) than one mile in depth (what a monstrous congeries of animals must this have been!), but have been universally difseminated in every place where either animals or vegetables were to be found. I do not push this reasoning farther. These hints are perfectly sufficient to shew, that the present age has no claim to infallibility in reasoning, more than those that are past; and that, therefore, they have no title to arrogate to themselves that claim of infallibility which the system whereon they at present repose with such ineffable complacency must necefsarily presuppose. I see no reason to believe that any human being, at the present hour, has discovered even a single elementary substance in nature; and if so, he cannot be possessed of data to form any one name, upon the principles of the new nomenclature, that shall be entitled to hold its place, according to the principles of their system, one moment after the fallacy in which the present name had

then, is absurd, and impiously extravagant; because it rests upon a supposition, which not even the confidence of modern philosophy will dare to avow; viz. that the inventors of it were pofseised of a perfect knowledge of the real primary elementary substances in nature.

Neither let it be conceived, that I wish to throw out any insinuations tending to detract from the merits of the person whose reasoning I have thus ventured to analyse. It was, in truth, because I respected the talents and the dispositions of the man, that I made choice of his work for an illustration. It would by no means have answered the purpose of the illustration if I had chanced to lay hold of some careless, insignificant draggler, in his heedlefs, ill-directed rambles through the seductive walks of literature. But if a man of the very first talents will mount his Pegasus, and urge him forward at the full top of his speed, through a country with which he is unacquainted, without taking the trouble first deliberately to explore the way, ought we to be furprised, if he should chance to run his head against a post, or get into a hobble, out of which he may find some small difficulty fairly to extricate himself. My aim in this efsay is, not so much to inform the ignorant, as to moderate the impetuosity of those who feel the superiority of talents; for I am fully convinced, that superiority of talents much more frequently betrays the possessor into error, than the want of them; and as men in general are afraid to correct these aberrations, they are suffered long to remain as sources of error to the weaker but well-intentioned portion of the com

munity. Who, I ask, but myself, would venture to publish this essay in the present day? I contend in the cause of truth; and in that cause I will stand unmoved, although, like Abdiel, I stood alone, and all others ranged themselves on the opposite side; nothing afraid of the decision of the age which many who read this will live to see.

Botanical Description of the Plant that produces the East-Indian Coutchouc. By Dr. Roxburgh.

AGREEABLE to my promise, I now proceed to give Dr. Roxburgh's description of the plant that produces the Coutchouc of Sumatra and Pulo-pinang, with farther remarks on that valuable substance.

Having obtained, he says, from Mr. FLEMING, very complete specimens, in full foliage, flowers, and fruit, "I was enabled to reduce it to its clafs and order in the Linnæan system. It forms a new genus in the clafs pentandria and order monogynia, and comes in immediately after tabernaemontana; conséquently belongs to the thirtieth natural order, or clafs, called by LINNEUS, in his natural method of classification or arrangement, contorta. One of the qualities of the plants of this order is, their yielding, on being cut, a juice which is generally milky, and for the most part of a poisonous nature.'

Dr. Roxburgh denominates this plant URCEOLA elastica, or coutchouc vine of Sumatra and PuloPinang, and gives the following reasons for this denomination." The generic name, Urceola," says

structure of the corol; and the specific name from the quality of its thickened juice."

"It does not appear," Dr. Roxburgh says, "that this vine has been taken notice of by any European till now. A substance of the same nature with the Coutchouc, and probably the very same, was discovered in the island of Mauritius by M. POIVRE, and from thence sent to France; but, so far as I know, we are still ignorant of the plant that yields it.

"The impropriety of giving to Coutchouc the term gum, resin, or gum-resin, every one seems sensible of, as it possesses qualities totally different from all such substances as are usually arranged under those generic names: yet it still continues, by most authors I have met with, to be denominated elastic resin, or elastic gum. Some term it simply Coutchouc, which I wish may be considered as the generic name of all such concrete vegetable juices (mentioned in this memoir) as possefs elasticity and inflammability, and are soluble in the efsential oils without the afsistance of heat;" and, although the name be not so pleasing to pronounce as some others, yet we wish the same rule may be adhered to universally.

Description of the Plant Urceola.

PENTANDRIA MONOGYNIA.

"GEN. CHAR. Calyx, beneath five-toothed; corol one petaled, pitcher-shaped, with its contracted mouth fivetoothed: nectary entire, surrounding the germs; follicles two, round, drupacious; seeds numerous, immersed in pulp.

URCEOLA ELASTICA.

Shrubby, twining, leaves opposite, oblong, panicles terminal; is a native of Sumatra, Pulo-pinang, and Malay countries.

"Stem, woody, climbing over trees, &c. to a very great extent, young shoots twining, and a little hairy, bark of the old woody parts thick, dark coloured, considerably uneven, a little scabrous, on which I found several species of mofs, particularly large patches of lichen; the wood is white, light, and porous.

Leaves, opposite, short-petioled, horizontal, ovate, oblong, pointed, entire, a little scabrous, with a few white scattered hairs on the under side.

"Stipules, none.

"Panicles, terminal, brachiate, very ramous.

"Flowers, numerous, minute, of a dull greenish colour, and hairy on the outside.

"Bracts, lanceolate, one at each division and subdivison of the panicle.

Calyx, perianth, one-leaved, five-toothed, permanent. "Corol, one-petaled, pitcher-shaped, hairy, mouth much contracted, five toothed, divisions erect, acute, nectary entire, cylindrick, embracing the lower two thirds of the germ.

"Stamens, filaments five, very short from the base to the corol. Anthers narrow-shaped, converging, bearing their pollen in two grooves on the inside near the apex: between these grooves and the insertions of the filaments they are covered with white soft hairs.

Pistil, germs two; above the nectary they are very hairy round the margins of their truncated tops. Style single, shorter than the stamens. Stigma ovate, with a circular band, dividing it into two portions of different colours.