is about to divide itself. The division then is made slopingly. The stripe points out the edges of the new funnel, and these are only the lips of the fresh polypus. You discover in them a pretty slow motion, which helps you to discern them. They approach each other insensibly, the body collects itself by degrees; a little swelling forms itself on the side, which is a new head. You already clearly distinguish two polypuses placed above each other. The upper polypus has the former head and a new tail; the inferior one a new head and the former tail. The upper polypus is connected with the other only by its lower extremity. By a motion it gives itself, it is at last detached from the other; and floats away in order to fix elsewhere. The inferior polypus remains fastened to the place where the funnel was before the division.

Net-polypuses likewise derive their name from the exterior form of their bodies; they pretty nearly resemble that of a fishing-net. They assemble in groups, and fasten on all the bodies they meet with in fresh water. They are very transparent. In the inside of the polypus there is formed an oblong and whitish body. As soon as it is formed, it descends by degrees, shews itself on the outside, and remains fixed perpendicularly on the polypus. It produces new ones every day; and the group they compose on the exterior part of the polypus, increases in growth. If these minute bodies be eggs, they are of a singular species; they are absolutely without any covering, and are neither membraneous or crustaceous. We cannot affirm of these eggs, that young are hatched from them, but are under a necessity of acknowledging, that these little oviform bodies unfold themselves. This developement is accomplished in a few minutes, and the polypus becomes the same as its mother imagine to yourself a bird that should issue from its mother's belly, entirely naked, rolled together like a ball, whose members should afterwards display themselves, and you will have a representation of the production of netpolypuses.

Cluster-polypuses propagate by dividing in the middle; armpolypuses do not multiply in this manner. They bring forth their young almost as a tree shoots forth its branches. A little bud appears on the syde of the polypus. Do not suppose that this bul contains a polypus, as the vegetable bud comprises a branch; it is itself the polypus in its growth. It increases in size and length, and at last separates from its mother. Whilst it is united to her, they both compose one body, as the branch with the tree. You are to understand this in the strictest sense. The prey, which the mother swallows, passes immediately into her young, and imparts the same colour to it. So that the whole

The polypus, which is partly turned back again as at first, is a real Proteus, that assumes all kinds of forms, which are all equally strange. Endeavour to represent to yourselves the polypus thus turned again. You remember that the insect is made in the form of a bowel. One part of the bowel then is turned backwards on the other; it there fastens and engrafts itself. In that case, the polypus is as it were double. The mouth encompasses the body like a fringed girdle; the arms are the fringe. They then point towards the tail. The forepart continues open; the other is usually shut up. You expect, no doubt, to see a new head and new arms, to grow out of the forepart; which you have observed in all the polypuses that have been divided transversely. But the polypus combines itself a thousand different ways, and each combination has its consequenses, which experience alone can discover to you. The forepart closes itself; it becomes a supernumerary tail. The polypus, which was at first extended in the right line, is curved more and more. The supernumerary tail lightens every day. The two tails resembles the feet of a pair of compasses. The compasses are partly open. The ancient mouth is at the head of the compasses. This mouth, which is fastened to the body, and embraces it like a ring, cannot discharge its functions. What then must become of the unfortunate polypus with two tails and without a head? How will it be able to live? Do you think that you have taken nature at unawares? You are mistaken. Towards the upper part of the polypus, near the ancient lip, there are forming not only a single mouth, but several; and this polypus, concerning which you inquired a minute ago how it could exist, is now a species of hydra, with several heads and mouths, and devours with all these mouths.

An account of the phenomena of Meteors and other fires, which arise from minerals in the earth, such as caverns, wells, and deep cellers.

AMONG fiery meteors are reckoned, thunder, lightning, ignes fatui, lambent flames, and what are called falling stars. Unless we account for these (as indeed it is easy to do) upon the principles of electricity, we must suppose they are owing to sulphureous or bituminous particles, floating in the air, which when collected in sufficient quantities, take fire by various means. If a large quantity of inflammable vapour takes fire at once, the flame tears the cloud with incredible force, as wel

an immense noise. But the light moving quicker than the sound, is seen before that is heard. Sometimes an exhalation of a milder kind takes fire, and produces lightning without thunder. When it thunders and lightens, it commonly rains too, the same shock driving together and condensing the clouds. And the wisdom of God appoints it so, for the preservation of his creatures. For if lightning falls on one who is thoroughly wet, it does him no harm at all. Not that the water quenches or resists the fire; but it conveys it into the ground.

High places are most frequently struck with lightning if they have sharp points, as spires of churches, or tops of trees, which as it were, attract the fire. It sometimes burns the clothes without hurting the body; sometimes breaks the bones without scorching the skin. It melts the sword in the scabbard, or money in the pocket, while the scabbard or pocket remains as it was. In general, it passes innocently through those things that make little or no resistance; but tears those in pieces with impetuous force which resist its passage.

One very particular effect of lightning, is what the vulgar call fairy circles. These are of two kinds. One kind is a round, bare path, about a foot broad, with green grass in the middle, and is frequently seven or eight yards in diameter. The other is a circle of the same breadth, is very green grass, much fresher than that in the middle. These are generally observed after storms of thunder and lightning. And it is no wonder, that lightning, like other fires, move circularly, and burns more at the extremity than in the middle. The second kind of circles, without all doubt, spring originally from the first: the grass, which was burnt by the lightning, growing afterward more fresh and green.

But of what kind was that meteor which appeared March 21, 1676? Two hours after sunset, it came over the Adriatic sea, from E. N. E. to W. S. W. and crossed over all Italy, being nearly vertical Rimini on the one side, and Leghorn on the other. It was at least thirty-eight miles high. In all places near its course, it made a hissing noise like a sky rocket. Having passed Leghorn, it gave a sound like that of a large cannon, and quickly after like a cart, running over stones. It was computed to move one hundred and sixty miles in a minute, which is above ten times as swift as the diurnal motion of the earth. Its smaller diameter was judged to be above half a mile. No wonder, then, that so large a body, moving with such incredible swiftness through the air, though so much rarified, should cause that hissing noise. It is much harder to conceive,how such an impetus could be impressed upon it: how this impetus should be determined, in a direction so nearly

parallel to the horizon! And what sort of substance it must be, that could be so impelled and ignited at the same time! Whatever it was, it sunk, and was extinguished in the Tyrrhene sea, to the W. S. W. of Leghorn. The great noise was heard, on its immersion into the water, the rattling sound upon its quenching.

On Thursday, March 19, 1719, there appeared at London, about eight at night, a sudden great light, moving after the manner, but more slowly than a falling star, in a direct line, a little beyond and with all below Orion's Belt, then in the south west. In its way, it turned tapering upward, and at last spherical, near as big as the full moon. It was whitish, with an

eye of blue, as bright as the sun in a clear day. It seemed in half a minute to move twenty degrees, and to go out as much above the horizon. There remained after it, for more than a minute, a track of reddish colour, such as that of red hot iron; and sparks seemed to issue from it, such as come from red hot iron, beaten upon an anvil.

Within doors the caudles gave no light; and without, not only the stars disappeared, but the moon, nine days old, though the sky was clear, and she was then near the meridian: so that for some seconds, we had perfect day. Its height was seventythree miles and a half. Hence it might be seen in all places, which were not distant from it more than two hundred and twenty leagues. Accordingly, it was seen, at the same instant over Spain, France, Great Britain, Ireland, Holland, and the hither parts of Germany.

Another appearance, which resembles lightning, in the aurora borealis commonly called northern lights. This is usually of a reddish colour, inclining to yellow, and sends out coruscations of bright light, which seem to rise from the horizon in a pyramidical form, and shoot with great velocity into the zenith. It appears frequently in the form of an arch. rises far above the regions of the clouds, yet never appears near the equator, but always nearer the poles.

Vapours of the same kind, that give rise to lightnings in the air, occasion damps in the earth. The damps usual in mines are of four sorts. The approach of the first and most common is known by the flame of the candle lessening till it goes out: as also by the men's difficulty of breathing. Those who escape swooning are not much hurt by this: but those who swoon away, are commonly on their recovery seized with strong convulsions. The second is the peasbloom damp, so called because of its smell. This comes only in summer, and is common in the Peak of Derbyshire. They who have seen the third sort of damp, describe it thus: in the highest part of the roof of those