contact; the process of moulding seemed, however, to be more rapid in this, than in the infusion made with heat.

A portion of the powder was digested with sixty times its weight of alcohol: the fluid at first assumed a dull olive colour, and gradually became more brown; the brown colour was increased by applying a gentle heat, but it still retained a considerable tinge of green. The fluid was then separated from the powder, and it gradually acquired a reddish brown colour, without any mixture of olive. The powder, after being subjected to the action of the alcohol, was found to have lost exactly half its weight; the residue was not very different in its appearance from the entire powder, except that it was rather more dry and fibrous.

The warm infusion, after being filtered, and while it was still recent, was subjected to the action of different re-agents, and by way of comparison, similar experiments were performed on an infusion of kino. The kino that I employed was the species commonly used in medicine, and which appeared to agree nearly with the description of the variety that is brought from Africa. By being heated with water the greatest part of it was dissolved, but after the addition of several successive portions of water, a little remained which was no longer capable of being acted on: this undissolved part was dark coloured, hard, and gritty. The infusion became opake as it cooled, but by filtration it was rendered nearly transparent. Its colour was very different from the infusion of the coccoloba, the latter being brown with a tinge of red, while the kino was redwith a slight tinge of brown. The re-agents employed were, 1. jelly prepared from isinglass, 2. muriate of tin, 3. oxy-sulphate of iron, 4. superacetate of lead, 5. tartarized antimony, 6. lime water, 7. sulphuric acid, and 8. subcarbonate of potash; the saline bodies were all in the state of saturated solution. The results were as follow:

'Thomson's Lond. Disp. 213.

The tincture of the coccoloba bark was not affected by the addition of water. Jelly and the oxysulphate of iron threw down precipitates nearly similar to those from the watery infusion, but the muriate of tin had no effect. A quantity of the tincture was slowly evaporated, and a residuum was obtained which was brittle, and of a browner colour than the extract from the infusion. It appeared to be scarcely soluble in cold water, but in hot water the greatest part was dissolved; the solution became muddy as it cooled, it was rendered transparent by heat, and again grew opake when the heat was withdrawn. It was then filtered, and an infusion was obtained which was nearly transparent, and of a light brown colour. The tincture of kino being treated in the same manner, a residuum was obtained, which was of a deep red colour, and of a more friable texture than the kino itself. The residuum was, for the most part, readily soluble in hot water, although a small portion of a black substance remained undissolved. This part was soluble in alcohol; and the solution was not precipitated by water. Comparative experiments were then made upon these two infusions, by adding to each of them the same re-agents as in the former instance; the effects were nearly similar to those mentioned above.

A portion of the residuum of the coccoloba, after the action of water upon it, was then digested in forty times its weight of alcohol, and a light olive tincture was produced, which gradually acquired a shade of brown. By this operation the pow

der lost about one-eighth of its weight. When the converse of this experiment was tried, i. e. when the residuum of the tincture was digested in water, scarcely any effect was produced, the infusion was slightly tinged by the oxysulphate of iron, and a very minute precipitate was produced by jelly.

From the above experiments we may conclude, that the extract of coccoloba is a substance of the same nature with the kino used in medicine; but that it differs from it so far as to show, that they are not derived from the same plant. They are very similar in their external appearance and physical properties; but there is an obvious difference in the colour, both of the infusion and tincture. The effect of the re-agents is also different; jelly producing a brown precipitate with coccoloba, and a reddish one with kino; iron a black precipitate with coccoloba, and an olive-coloured one with kino. The effects of lime and sulphuric acid are much less with kino than with the coccoloba: there is no precipitate thrown down either by antimony or the subcarbonate of potash from kino, while the effect upon the coccoloba is very considerable. The soluble part of the coccoloba bark seems to consist principally of tan, which is in all respects similar to the tan of the gall nut; while the tan of which kino is chiefly composed, resembles that of rhatany, and the substance which is artificially procured by Mr. Hatchett's process. The tan of the coccoloba bark is accompanied, as is usually the case, with gallic acid, and it likewise exhibits those properties which have been ascribed to the presence of a specific vegetable product called extractive; but the existence of this I think has not been distinctly proved. The substance procured by evaporating the watery infusion, is in part rendered insoluble by the process, and the same would appear to be the case with kino, as it is probable that kino is formed by evaporation, from an infusion or decoction. Its appearance indicates that it has undergone. this kind of operation, and I am not acquainted with any in

See Nicholson's Journ. 24. 215-222.

stance in which a substance, composed principally of tan, naturally exudes from a plant.

That part of the coccoloba which is soluble in alcohol, and not soluble in water, was examined by evaporating the tincture formed from the aqueous residue of the bark. By the evaporation, a substance was left, the greatest part of which was of a greenish brown colour, and along with it a little reddish matter. Its odour was fragrant, something like that of the balsam of tolu. Water that had been digested upon it produced only a slight effect with isinglass, and the oxysulphate of iron. Neither the tincture of this substance nor of the entire extract of coccoloba were precipitated by water. The substance left, after digesting in water the residue obtained by evaporating the tincture of the recent bark, was very similar, in its colour, odour, and consistence to that procured above: it approaches to the nature of the resinous balsam, but its solution in alcohol is not precipitated by water, although it is not itself soluble in that fluid.

The following may be regarded as an approximation to the analysis of the bark of the coccoloba:

Hints relative to the most eligible method of conducting Meteorological Observations. By JOHN GRISCOM, Fellow of the Literary and Philosophical Society; member of the Medical Faculty of Queen's College, New-Brunswick, (N. J.) Professor of Chemistry in Columbia College, &c. NewYork, 4to.

[Read before the Literary and Philosophical Society of New-York, on the 8th of December, 1814.]

AN accurate register of a careful and extensive series of observations on atmospherical phenomena, under the direction of this society, might, it is conceived, very usefully contribute to enlarge our knowledge of the nature of those changes, so important to human welfare, and to throw into the common stock of philosophy, facts conducive to its advancement.

Vicissitudes of weather are regarded, by the greater part of mankind, as events altogether fortuitous in their nature, and subject to influences, the precise order of which cannot be ascertained.

Philosophers cannot, indeed, boast of much progress in this field of discovery. Governed, as those changes doubtless are, by chemical, rather than by mechanical laws, it is not to be expected that mankind will ever arrive at that perfection of knowledge, with respect to these phenomena, which has erowned their labours in relation to the heavenly bodies. But, although an acquaintance with the ultimate principles upon which atmospheric changes depend may never be attained, it is scarcely to be doubted, that a diligent course of observation and experiment, performed by men of science, in various parts of the globe, would furnish results which might serve as a foundation for a theory much more perfect than any which has been proposed.

Facts of such common occurrence, and so fully within the reach of observation, as are those of wind, rain, storms, changes of temperature, &c. are, doubtless, susceptible of arrangement and classification, as well as those in other de