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.

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 enter. ing 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 cru. cifixes, Virgin-Marys, &c. found in the heart of trees; as, for ex

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 horn 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.

CHAPTER VIII.

FAIRY RINGS.

THIS 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

storm passed over the western extremity of London. I was then at Battersea, and made no other remark on the phænomena than that the explosions, which were very marked and distinct, were in many instances forked at the lower end, but never at the top; whence it follows, that the clouds were in the positive state for the most part. On the following Sunday, namely the 24th, I happened to be n Kensington Gardens; in every part of which extensive piece of ground the lightning had left some marks of its agency, chiefly by discoloration of the grass in zigzag streaks, some of which were fifty or sixty yards in length. Instances of this superficial course of the lightning along the ground, before it enters the earth, are sufficiently frequent. But the circumstances which attracted my atten. tion the most was seen in a small grove of trees at the angular point of one of the walks."

[Journal of Natural Philosophy, Vol. I. p. 546.

Dr. Darwin is well known to have been one of the chief advocates for this electrical hypothesis. It is thus he adverts to it in his Botanic Garden, Canto I. 1. 369:

So from dark clouds the playful lightning springs,

Rives the firm oak, or PRINTS THE FAIRY-RINGS.

Upon which he has the following note towards the end of the volume :

"There is a phenomenon, supposed to be electric, which is yet unaccounted for; I mean the Fairy-rings, as they are called, so often seen on the grass. The numerous flashes of lightning which occur every summer are, I believe, generally discharged upon the earth, and but seldom (if ever) from one cloud to another. Moist trees are the most frequent conductors of these flashes of lightning, and I am informed by purchasers of wood that innumerable trees are thus cracked and injured. At other times larger parts or promi-" nences of clouds gradually sinking as they move along, are discharged on the moister parts of grassy plains. Now this knob or corner of a cloud, in being attracted by the earth will become nearly cylindrical, as loose wool would do when drawn out into a thread, and will strike the earth with a stream of electricity perhaps two or ten yards in diameter. Now, as a stream of electricity displaces the air it passes through, it is plain no part of the grass can be burnt

by it, but just the external ring of this cylinder, where the grass can have access to the air; since without air nothing can be calcined. This earth after having been so calcined becomes a richer soil, and either funguses or a bluer grass for many years mark the place. That lightning displaces the air in its passage is evinced by the loud crack that succeeds it; which is owing to the sides of the aerial vacuum clapping together when the lightning is withdrawn. That nothing will calcine without air is well understood, from the acids produced in the burning of phlogistic substances, and may be agreeably seen by suspending a paper on an iron prong, and putting it into the centre of the blaze of an iron furnace; it may be held there some seconds, and may be again withdrawn, without its being burnt, if it be passed quickly into the flame, and out again, through the external part of it which is in contact with the air. I know some circles of many yards diameter of this kind near Foremark, in Derbyshire, which annually produce large white funguses and stronger grass; and have done so, I am informed, above thirty years. This increased fertility of the ground by calcination or charring, and its continuing to operate so many years, is well worth the attention of the farmer; and shews the use of paring and burning new turf in agriculture, which produces its effect, not so much by the ashes of the vegetable fibres, as by charring the soil which adheres to them.

These situations, whether from eminence or from moisture, which were proper once to attract and discharge a thunder-cloud, are more liable again to experience the same. Hence many fairy-rings are often seen near each other, either without intersecting each other, as I saw this summer in a garden in Nottinghamshire, or intersecting each other, as described on Arthur's seat, near Edinburgh, in the Edinb. Trans. Vol. II. p. 3."

[Bot. Gard. Additional Note xiii. p. 26.

There are, nevertheless, various objections to this hypothesis ; and which seem rather to establish the opinion that these singular patches are the result of the insidious operation of the agaricus orcades, a fungus common to the moist wastes of our own country. Mr. Gilbert White first observed, with his usual correctness, that the cause of the Fairy-rings exists in the turf, and is conveyable with it; for the turf of my garden walks," says he, " brought from the down above, abounds with these appearances, which vary

their shape, and shift their situation continually, discovering themselves now in circles, now in segments, and sometimes in irregular patches and spots. Wherever they obtain, PUFF-BALLS ABOUND; the seeds of which were doubtless brought in the turf."

[Nat. Hist. Vol. II. p. 259.

This puff-ball has been very plausibly stated, and nearly ascer tained, by Dr. Withering, to be that of the agaric we have above referred to. An able writer in the Monthly Magazine, for April, 1803, whilst he embraces this latter opinion, states several very forcible reasons against the electrical hypothesis.

"However plausible," says he, "this idea (that of electricity) may seem to the theoretical philosopher, it is found by the observant naturalist to be inadequate to the explication of the phenomenon. Without intending to enter into any kind of controversy upon this subject, which, doubtless, will be thought by some readers already to have occupied too many pages of the most popular miscellanies, allow me to mention a few facts which appear irreconcilable with the above-mentioned theory.

"Moisture is stated as requisite for the attraction of lightning to turf-but fairy-rings are discoverable in situations which have no pretensions to moisture.

"It is next observed, that the cloud attracted by moisture, will become cylindrical, or conical ; and consequently the stream of electricity descending on the turf, by its external ring will there form the circular mark vulgarly called a fairy-ring; but instead of these marks being uniformly circular, which they would be from such a cause, they, as Mr. White accurately states, vary their shape, and shift situation continually, discovering themselves now in circles,' (though seldom entire) now in segments, and sometimes in irregular patches and spots.'

The gradual shifting of situation furnishes another objection to the phenomenon's being occasioned by lightning; as does the not mere permanency, or decrease, or dying out, of such marks, but the annual increase of size which may be frequently noticed in some; and the fact that fairy-rings originate in small patches, militates strongly against such a theory.

"It is urged on the above hypothesis, that in the rings formed by lightning the turf is thereby calcined—but it must occur to every one