3. "Alcohol does not dissolve any portion of the wax, unless heat be applied.

"

Two fluid ounces of boiling alcohol, specific gravity 0·826, dissolve about ten grains of the wax, of which eight grains are deposited as the solution cools, and the remaining two grains may be afterward precipitated by the addition of water, or may be obtained unaltered by evaporating the alcohol.

"The solution of the wax in alcohol has a slight green tinge.

4. "Sulphuric ether, specific gravity 0-7563, dissolves a very minute portion of the wax, at the temperature of 60°.

"Two fluid ounces of boiling sulphuric ether dissolve thirty grains of the wax, of which twenty-six grains are deposited by cooling the solution, and the remaining four grains may be obtained by allowing the ether to evaporate spontaneously.

5. "The fixed oils very readily dissolve the wax at the temperature of boiling water, and form with it compounds of an interme diate consistence, very analogous to those which are obtained with common bees-wax."

From the detail of experiments, it appears, that, although the South American vegetable wax possesses the characteristic properties of bees'-wax, it differs from that substance in many of its chemical habitudes; it also differs from the other varieties of wax, namely, the wax of the myrica cerifera, of lac, and of white lac.

The attempts made by Mr. Brande to bleach the wax were conducted on a small scale; but from the experiments related, it appears, that, after the colour has been changed by the action of very dilute nitric acid, it may be rendered nearly white by the usual means. He had not had sufficient time to ascertain whether the wax can be more effectually bleached by long continued exposure; nor had he had an opportunity of submitting it to the processes employed by the bleachers of bees'-wax.

Perhaps the most important part of the present inquiry is that which relates to the combustion of the vegetable wax, in the form of candles.

The trials which have been made, to ascertain its fitness for this purpose, are extremely satisfactory; and when the wick is properly proportioned to the size of the candle, the combustion is as perfect and uniform as that of common bees'-wax.

The addition of from one-eighth to one-tenth part of tallow is

MARKS AND SUBSTANCES FOUND IN TREES.

313

sufficiently to obviate the brittleness of the wax in its pure state, without giving it any unpleasant smell, or materially impairing the brilliancy of its flame. A mixture of three parts of the vegetable wax, with one part of the bees-wax, also makes very excellent candles.

[Humboldt and Bonpland. Pantalog. Phil. Trans. Barton.

CHAP. VII.

EXTRANEOUS MARKS AND SUBSTANCES FOUND IN THE TRUNKS OF TREES.

In a preceding section, on the physiology of plants, it has been

IN

N

observed, that the trunk consist of hard wood, constituting its heart; soft wood or alburnum; inner bark or liber; and outer bark or cor tex: and that the hard wood is produced and increased by an annual formation of new alburnum or liber. Wildenow supposes the latter; and that the liber of the one year is in the next converted into alburnum, and the alburnum of the same year into hard wood. Mr. Knight conceives the liber is not concerned in this conversion, and that the alburnum alone is converted into hard wood. In either case, it is easy to foresee that any durable marks or foreign substances introduced through the bark of the tree down into the soft wood, must necessarily, as this wood becomes converted into hard wood, and covered with new annual layers of soft wood, be transferred by degrees towards the interior of the trunk' and be found in the hard wood, or heart of the tree, instead of in the alburnum or external part.

We hear curious accounts of letters, rude cuts or engravings, and foreign bodies, being found in the middle, or near the middle, of the trunks of many trees; to the great astonishment of those who have made the discovery, and have not been aware of the true nature of the growth of the trunk, which we have thus endeavoured to point

out.

The following we select from the Philosophical Transactions, as sufficient examples of this curious fact.

1. Letters found in the Middle of a Beech.

By J. Theodorie Klein, Secretary of Dantzick, F. R. S.

In the year 1727, a beech-tree was felled near Elbing, for the domestic use of John Maurice Moller, then post-master of Elbing, now secretary of his native city. The trunk being sawed into pieces, one of these, three Dantzic feet six inches long, cleft in the house, discovered several letters in the wood, about one inch and a half from the bark, and near the same distance from the centre of the trunk. Two of these, DB, show their old bark smooth and sound. The wood lying between the letters and the bark of the trunk, as well as that between the letters and the heart of the tree, is likewise solid and sound, bearing not the least trace of letters. The characters DB, being somewhat hollow, receive the mark of the letters DB.

The same letters are seen in the bark of the tree, only that they are partly ill shaped, partly almost effaced; whereas those within bear a due proportion, as if done with a pencil.

It is an ancient custom to cut names, and various characters, on the rinds of trees, especially on such as are smooth. That this has happened to our beech, the mere inspection of the bark sufficiently shows. An incision made, the tubuli conveying the nutritious juice, and the utriculi in which it is prepared, are divided and lacerated, and more of them, as the incision was made deeper and wider: and consequently the sap is not carried on in the circulation, but extravasated and stopped at the wounds. Hence the origin of the characters in the bark and wood.

Now as a new circle of fibres grows yearly on the tree, between the wood and bark, a number of these may in a process of years, more and more surround the engraved characters, and at length cover them. And this number was the greater in our beech, on account of better than half a century having elapsed since the incision, which was made in the year 1672, as appears on the outside of the bark. But while new circles of fibres are successively added, the tunicle or skin of the bark is broken each time, and the utriculi extended and dilated.

M. Klein also mentions several other instances of the same kind, and accounted for in the same manner, as treated of by different authors; viz. Solomon Reisel, John Meyer, Luke Schroeck, John Chrit. Gottwald, John James Scheuchzer, and John Melch. Verdries.

2. Large Deer's Head found in the Heart of an Oak.

By Sir John Clark, F.R.S.

BEING lately in Cumberland, Sir J. C. there observed three curiosities in Winfield-Park, belonging to the Earl of Thanet. The first was a huge oak, at least sixty feet high, and four in diameter, on which the last great thunder had made a very odd impression; for a piece was cut out of the tree, about three inches broad, and two inches thick, in a straight line from top to bottom. The second was, that in another tree of the same height, the thunder had cut out a piece of the same breadth and thickness, from top to bottom, in a spiral line, making three turns about the tree, and entering into the ground above six feet deep. The third was the horn of a large deer found in the heart of an oak, which was discovered on cutting down the tree. It was found fixed in the timber with large iron cramps; it seems therefore, that it had at first been fastened on the outside of the tree, which in growing afterwards had inclosed the horn. In the same park Sir John saw a tree thirteen feet in diameter.

3. Remarks on the foregoing.

By Dr. Mortimer.

THIS horn of a deer, found in the heart of an oak, and fastened with iron cramps, is one of the most remarkable instances of this kind, it being the largest extraneous body we have any where recorded, thus buried, as it were, in the wood of a tree. If J. Meyer, and J. Pet. Albrech had seen this, they could not have imagined the figures seen by them in beech-trees to have been the sport of nature, but must have confessed them to have been the sport of an idle hand. To the same cause are to be ascribed those figures of crucifixes, Virgin-Marys, &c. found in the heart of trees; as, for example, the figure of a crucifix, which I saw at Maestricht, in the

L

church of the White Nuns of the order of St. Augustin, said to be found in the heart of a walnut-tree, on its being split with lightning. And it being usual in some countries to nail small images of our Saviour on the cross, of Virgin-Marys, &c. to trees by the road-side, in forests, and on commons; it would be no greater a miracle to find any of these buried in the wood of the tree, than it was to find the deer's horns so lodged.

Sir Hans Sloane, in his noble museum, has a log of wood brought by Mr. Cunningham from an island in the East Indies, which, on being split, exhibited these words in Portuguese, DA BOA ORA. i. e. Det [Deus] bonam horam.

[Editor. Phil. Trans. 1739, Vol. XLI.

CHAP. VIII.

FAIRY RINGS.

THI

HIS curious phenomenon has been differently accounted for. The following is Mr. Nicholson's description and explanation: "the appearance in the grass," says he, "commonly called Fairy Rings, is well known. It consists either of a ring of grass of more luxuriant vegetation than the rest, or a kind of circular path in which the vegetation is more defective than elsewhere. It appears to be pretty well ascertained, that the latter state precedes the former. Two causes are assigned for this phenomenon: the one, which cannot be controverted, is the running of a fungus; the other, which has been considered as an effusion of theory, is grounded on a supposition that the explosion of lightning may produce effects of the same kind on the ground, as Dr. Priestley's battery was found to produce on the polished surface of a plate of metal, that is to say, a series of concentric rings. Some observations, which I find in my commonplace book, appear to show that this last effect may, in certain circumstances, take place.

"On Tuesday the 19th of June, 1781, a very powerful thunder