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The first of these contains in the centre, and in four places within the area of the circle, large cists, or, as they now appear from the soil being removed from them, large cromlechs exactly of the same construction as that well-known Druidical structure, “Kits-Coty-House," and numberless others.* They are formed of large limestones (the general formation of the district), and have all had covers, or cap-stones of the same, but only two with these cap-stones perfect now remain.
The accompanying plan of some of these cists gives the situation of
the stones forming the sides of the large chamber; of the pasage leading to it; of the slabs which closed its entrance; and of the covers or cap-stones. The chamber is rather more than five feet in height, and the largest cap-stone about seven feet square and of great thickness. A kind of wall similar to those which have been found to encircle some of the Etruscan tumuli, forms the circle of this mound, which rises to a height of more than fifteen feet from the surface of the ground. The “ Five Wells " tumulus contains one of the most perfect examples now remaining of this kind of arrangement. “It consists of two vaults or chambers, situated in the centre of a cairn, about thirty yards in diameter, each approached by a separate gallery or avenue, formed by large limestones standing edgeways, extending through the tumulus, respectively in a south-east and north-west direction.” Another five-chambered tumulus is Ringham-Low, which has, as yet, been only partially examined.
In some instances, the barrows are formed almost wholly of earth, and where they contain examples of urn burial, or of cremation without urns, the indications are frequently very striking. It not unfrequently happens that the spot where the
* As a rule the structures known as cromlechs, Druidical altars, etc., ara these large sepulchral cists from which the earth forming the mound has at some time been removed.
funeral pyre has been lit can very clearly be perceived, and, as I have said before, in these instances the ground beneath is generally burned to some considerable depth. Where it was intended that the remains should be collected together, and placed in an urn for interment, I apprehend, from careful examination, that the urn being formed of clay-most probably, judging from the delicacy of touch, and from the impress of fingers which occasionally remains, by the females of the tribes—and ornamented according to the taste of the manipulator, was placed in the funeral fire and there baked, while the body of the deceased was being consumed. The remains of the calcined bones, the flints, etc., were then "scraped” up together and placed in the urn; over which the mound was next raised. When it was not intended to use an urn, then the remains were collected together, piled up in a small heap, and covered to some little thickness with rth (and occasionally small stones). Another fire was then lit on the top of this small mound, which had the effect of baking the earth, and enclosing the remains of calcined bones, etc., in a kind of crust resembling in colour and hardness, a partly-baked brick.
Having now spoken of the principles of construction of the Celtic grave-mounds of Derbyshire, and described the various modes of interment which they exhibit, I shall in my next paper proceed to describe the pottery and the objects of flint, bone, and stone, which they contain.
(To be continued.)
THE NOVEMBER SHOOTING STARS.
BY RICHARD A. PROCTOR, B.A., F.R.A.S.
(With a Plate.)
It is probable that there will be this year an exhibition of the November shooting stars, though it is uncertain whether the phenomenon will be so well seen in Europe as it was last year.
As a display the shower is not likely to be so splendid as it was in 1866, since on November 14th of the present year, the moon will be nearly full. However, there can be no doubt that the November meteors will be looked for again with great interest, since the discoveries which have been made respecting the orbit in which they move, have presented them to us in a new aspect.
When the shower of November last was under discussion, it was very noteworthy how indistinct were the views of many persons—I may even say of many astronomers—respecting the relations of the earth’s globe, as it travelled onwards rotating in its orbit, to the meteor stream which it encountered. I do not here refer to the doubt and obscurity under which the question of the path actually pursued by the meteors rested at that time. The investigation of this question was one of extreme difficulty, one which taxed—and not lightly—the powers of the highest modes of mathematical analysis. appeared to find considerable difficulty, or failed altogether in forming an estimate of the circumstances under which the meteors became visible to us. The existence of a “ radiant point” from which all the shooting stars appeared to travel, in whatever part of the sky they made their appearance, was a phenomenon which — although in reality it inferred the solution of the problem of the meteors' origin—yet presented difficulties to many observers. The questions that were asked and the suggestions that were offered on this and kindred points, were many and amusing. One observer, noticing the comparative absence of meteors from the immediate neighbourhood of the “radiant point,” suggested in explanation of the peculiarity, that the earth was passing through a sort of tunnel traversing a bed of meteors; thus in the path along which the earth travelled, there were no meteors or few-previous passages along the same track having cleared the waybut many meteors grazed the earth's atmosphere, the bore of the tunnel only allowing the solid globe of the earth to pass freely. And, indeed, the supposition that shooting stars are only seen when grazing our atmosphere has been commonly entertained and expressed even by astronomers of eminence. Sir
John Herschel, for example, speaks of meteors as “bodies extraneous to our planet, which only becomes visible when in the act of grazing our atmosphere.” The idea, however, is wholly erroneous, as we shall presently see. Another remarkable question which was asked soon after the occurrence of the November shower, served still more clearly to exhibit the indistinctness of the views commonly held; meteors having been seen at Cape Town at the same hour (actual time) as in England, it was asked how the same meteors could be seen in both places, unless they had travelled as satellites round the earth? An eminent chemist, who has lately published a work on meteors, speaks of the received opinion of the cosmical origin of meteors, as, after all, merely conjectural, and he evidently leans towards the theory that they are satellites of the earth. Lastly, in Guillemin's “Heavens," a view is expressed and illustrated by an elaborate figure), which is wholly inconsistent with observed appearances. I refer to the notion that a single stream of bodies could give rise to both the November and August showers.
It is evident, therefore, that there is room for a careful examination of the actual state of things during the occurrence of the November shower. By considering the position of England on the rotating earth, during the time of the display, we shall be able to form clear views on this point.
I must first, however, mention briefly the true meaning of the existence of a “radiant point.” Once this phenomenon is established, all doubt whatever respecting the cosmical origin of a shooting star shower disappears. It is not true that the theory of a cosmical origin is now a conjectural one; it is established on a thoroughly firm basis. The phenomenon of a radiant point proves in fact this, that the paths in which the meteors intersect our atmosphere, are all parallel in space throughout the time that the shower is visible. Now the display lasting several hours, during which the earth moves through a large angle round her axis of rotation, it is quite clear that the display cannot have a terrestrial origin, since if it had, the direction of the shooting stars might be expected to change correspondingly, and would certainly not change after so artificial a manner that for several places at once the effects of the earth’s rotation would be exactly compensated. An equatorial telescope, for instance, is made by clockwork always to point to the same star, but we know that no telescope fixed at random and moved at a random rate would do so. Just, therefore, as a person seeing the same star for a considerable time through the tube of a telescope, knows certainly that he is looking through an equatorial rendered artificially independent of the earth's rotation-so, seeing shooting stars moving always from a fixed point among the stars, we know for certain that the direction of their motion is independent of the earth's rotation, and therefore—there being no possibility of an artificial arrangement corresponding to that of the equatorial—that the shooting stars come from external space. The notion of a lunar origin, and the satellite theory of meteors are similarly overthrown, though indeed, at the present day, no competent person entertains either of these views, which are for other reasons, wholly untenable. When the occurrence of a “radiant point” is coupled with “annual periodicity and independence of geographical position, referring us at once to the place occupied by the earth in its annual crbit,” the most sceptical (or, in this case, we must say those least able to appreciate the mathematical demonstration of the meaning of a radiant point), must be led “ directly to the conclusion that the earth is liable to encounters or concurrences with meteor streams in their progress of circulation round the sun."
It must be mentioned that the earth's motions have their effects upon the apparent motion of bodies moving in space. The motion of rotation, however, may be neglected in comparison with the motion of revolution and the proper motion of meteoric bodies. Travelling in space, under the sun's attraction, they cannot, at the moment of encountering the earth, be moving with a less velocity than that due to a body moving circularly round the sun at the earth's distance (a rate very slightly less than the earth’s) and they may have a velocity nearly half as great again as this. Between these values their velocity necessarily lies. Further, their velocity, relatively to the earth, must lie somewhere in value between the sum and difference of their actual velocity and the earth's, or between zero and about forty-five miles per hour; the first value giving the extreme case of meteors travelling in the same direction, and at the same rate as the earth; the second giving the case of meteors travelling in a parabolic orbit, and encountering the earth directly, just when they are in perihelion.
I have mentioned these limits and considered the nature of meteors' motion relatively to our earth, because it is on this relative motion that the position of the “radiant point" depends. If we suppose the earth reduced to rest, and her motion, reversed, added to the motion of the meteoric stream, we get the same relative motion, and the same radiant point as under the actual circumstances of the case. For clearness of explanation let us suppose this to happen, and that on the night of November 13–14 the earth's motion of revolution is non-existent (her motion of rotation continuing, however), and that the meteors are sweeping towards her from their radiant point (i.e. at a rate and in a direction resulting from the