horizontally. Of this he gives various striking instances. In fact, all the large, intensely brilliant meteors, move across the sky more or less horizontally, while those which fall near the perpendicular are always small and inconspicuous. The paths of the large and brilliant meteors of Bononia 1670, of 1719 and 1783 in England, were horizontal, while those of Weston, U.S., 1807, of Benares and of L'Aigle, which were less bright, moved in more inclined paths. He observes that the most extraordinary circumstance is the enormous apparent magnitude of the luminous mass or ball, as calculated from the ascertained distance. Thus the Weston meteor was 500 feet in diameter, and those of 1719 and 1783 were estimated at half a mile. Yet the quantity of matter known to fall has been but very small in comparison. It has been alleged that only a few fragments were attracted to the earth while the great mass rebounded from the atmosphere, a condition which the author contends is impossible. He is of opinion that the actual solid masses of these bodies are very much smaller, and then adverts to the observations of Professor Lawrence Smith (of which an account was given in the last Report), who has assigned an optical cause for this phenomenon.

The author, however, dissents from that conclusion, and alleges that the effect in the experiments there mentioned, of apparent great enlargement in the discs of luminous bodies seen at a distance, is really due not to any cause analogous to irradiation, or of an ocular kind, as there supposed, but simply to the reflective power of the atmosphere, which he considers to be made out 1858.

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by placing near the luminous body any small reflecting substance, and observing at a distance the illumination which it seems thus to spread to some distance around. In a word, he considers the effect in these experiments as due to illuminated air, which became visible as distance rendered the glare of the bright central point less overpowering to the eye.

Now this cause he contends cannot produce any effect in the case of meteors above the atmosphere, or even its higher rarefied regions.

"Meteoric stones, fire-balls, and shooting-stars are only luminous at or beyond the boundary of our aërial atmosphere, and cease to be so on their entrance into the denser air..... Of the extraordinary illuminating power of the fluid which burns around shooting-stars, we may be convinced from the vast amount of light which these objects emit, compared with their diminutive size. Although some observers, judging from their luminosity, have ascribed to them a diameter of from 80 to 120 feet, yet from the manner in which so many myriads of them have been lost in the atmosphere during the great meteoric showers of 1799 and 1833, we cannot assign to them a higher rank than hailstones or drops of rain, so far as actual magnitude is concerned." -(p. 95.)

The author is led to his explanation of the luminosity of meteors from the theory of the solar light, which assigns to the external photosphere of his globe the locality of the luminous emanation; and this photosphere he considers to arise simply from the intense condensation upon and near his surface, of the luminiferous ether, the same as the resisting medium, diffused through the planetary spaces. He rejects the idea of combustion or chemical changes being the source of the sun's luminosity; as these must in time become exhausted, and the supply of light and heat be consequently interrupted. He alludes to the query of Newton, asto why and how it was that lucid matter should be separated and made to form the sun, while opake matter was distributed among the minor bodies of the system. He then adds, -" But there is no necessity for this unnatural division of matter; since even if the sun were identical in composition with his attendants, yet in consequence of the great superiority of his attraction his surface would necessarily become the focus in which the ether of space must display its luciferous properties." (p. 98.)

The same law he conceives to apply to the fixed stars; he rejects the idea of the luminosity being due to any mechanical action on the ether dependent on the rotation of these bodies, for then Jupiter and Saturn, by reason of their far greater rotatory velocity, ought to be more self-luminous than the sun. He contends that it is due to "the chemical action which may be expected to take place in the etherial fluid as it condensed around the great sphere." -(p. 101.)

He raises other objections against the theory of Prof. W. Thompson, which was briefly described in a former Report, ascribing the solar light to the impact of innumerable meteors on his surface.

"The (etherial) fluid is so much rarefied in the interplanetary domain, that no chemical changes can take place between its elements, except where it is collected around the largest spheres and compressed by their powerful attraction. In obedience to the law of gravity, which exerts a universal control over all matter, atmospheres of the etherial fluid are collected around the earth and the other large planets, but they are not sufficiently dense for chemical action, except in cases where they receive an additional pressure from meteoric stones sweeping through them with furious rapidity. When these cosmical bodies, on falling to the earth's surface, move in adirection almost horizontal, they take a longer course through the verge of the atmosphere, and the etherial medium is stimulated to chemical activity by the pressure, not only from the meteoric mass itself, but also from the particles of air which it drives in every direction from its passage. As such a chemical action must be attended with a development of heat and light, it is not surprising that meteorites are luminous before reaching the confines of the air, and that their brilliancy is exhibited on a gigantic scale when their paths are almost parallel to the horizon." (p. 93.)

In further illustration of these views, and to correct some misapprehension which has existed respecting them, it will be desirable here to add an extract of a letter to Prof. Powell from Mr. Daniel Vaughan.

"Cincinnati, Ohio, October 9, 1858.

"I deem it necessary to offer an explanation of the main point of my theory, as the idea I have endeavoured to convey in relation to it has not been correctly understood. I therefore take the liberty to say, that I do not regard meteoric light as due to the presence of a luciferous atmosphere belonging to the meteorite itself; for I cannot believe that any appreciable quantity of ether or of inflammable gas could be confined around such small bodies, or retained by their feeble attractive power after they come in conflict with the air. On the contrary, I have maintained that the light arises from the atmosphere of luciferous ether, which envelopes the earth and which is rendered luminous by the powerful compression of meteorites as they move through it with immense velocities.

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"In obedience to the law of gravity, the ether of space must be condensed about all the large planets; but it must undergo the greatest condensation at the surface of the sun. On this vast body the density is sufficiently great to admit an incessant chemical action, giving rise to an unfailing development of heat and light; whereas, in the luciferous envelope of a planet, the same phenomenon cannot be expected, except on the fall of meteoric masses. the extent to which the compression of the ether is increased by falling meteorites some idea may be collected from the fact, that a body flying near the earth's surface at the rate of 20 miles a second, would impart to the air a pressure of 150,000 pounds to the square inch, or over ten thousand times the ordinary pressure of the atmosphere. We may therefore conclude that the etherial atmospheres of the several planets must display its illuminating power around the meteoric body, where it is compressed as intensely as it is on the sun's surface.

"A certain degree of compression or density being necessary for chemical action in the ether which maintains solar light, it cannot manifest its lightproducing energy in the wide domains of space, nor even on the planets, except in the rare cases of meteoric falls; and it must make the largest spheres above the theatres of its luminous action. My theory, therefore, not only accounts for the fact that the planets are not self-luminous, but also gives intelligence of the vast size of the fixed stars.-DANIEL VAUGHAN.”

Mr. Vaughan has given some account of his views to the British Association, 1857; see Sectional Proceedings, p. 42: also in some Essays published in 1853 and 1854, and in an article in the American Journal of Science and Art for May 1855.

No. 2. The subjoined extraordinary statement is copied from the 'Times' of Dec. 4. It bears the appearance of a simple straightforward account of fact, the nature of which seems difficult to conjecture. It is here inserted simply in the hope of attracting attention, and that in time some light may be thrown upon it by other observations.

Extract of a letter to the Editor of the Times, Dec. 4, 1858.

"... Last night (Nov. 30), at 15 minutes to 9, it being very dark and raining heavily, I was ascending one of the steep hills in this neighbourhood, when suddenly I was surrounded by a bright and powerful light which passed me a little quicker than the ordinary pace of man's walking, leaving it dark as before. This day I have been informed that the light was seen by the sailors in the harbour, coming in from the sea and passing up the valley like a low cloud.... JABEZ BROWN."

Boscastle, Dec. 1.

No. 3.

At 6 p.m. a luminous ball was seen in the region of the the moon, and higher than that luminary at the time. larger and brighter than any star of the first magnitude.

Oxford, Sept. 13. sky to the east of It appeared much It carried with it

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a train or tail like the tail of the comet now visible, and of about the same length. First was seen the ball, then the tail appeared, in a nearly horizontal line, then ball and tail disappeared. It seemed as though it came out, ran along the sky for a short space, and then entered the sky again. From a Lady in a letter to Professor Phillips.

No. 4.-The following account of a meteor was communicated by Prof. Stevelly to the British Association, Section A, at the Meeting (1858).

"On Wednesday evening, the 7th of October, 1840, as a number of us were returning from a Lecture on Storms, delivered by Mr. Espy in the rooms of the Natural History and Philosophical Society of Belfast, as we were passing along the east side of College Square, a beautiful meteor appeared for a few seconds, almost due south of us, but a little to the west, and so bright that you could distinctly read by its light. It was then within about 20 minutes to 10 o'clock; the moon was shining, though at the moment obscured by a cloud; and afterwards, when I found that others had seen the same meteor at a distance, we estimated, as accurately as we could, the altitude at which it had been seen, and found it at about 30°. On the night of Friday, the 9th, or two days after, I travelled to Dundalk by the Dublin mail coach, and the guard, Joseph Hill, asked me, had I seen the very brilliant flash of light on Wednesday evening, at about a quarter to ten o'clock. I told him I had, and inquired from him the particulars of where and how he saw it. He informed me of the place, which was about 5 miles out of Dublin, where the road was very straight, and tending to the north. He had seen it, as he explained, almost overhead, but somewhat to his right hand, and it was so bright for some seconds that the entire place around was lighted up so that a person could distinctly read by it. It had, therefore, been vertically over a place about 75 Irish miles from Belfast, and from these data it is easy to calculate its altitude above the earth, which must have been about 43 miles. A few days afterwards, the same guard, Joseph Hill, sent me the following letter and extract from the 'Warder' Dublin newspaper of Saturday the 10th, which confirms Hill's accuracy, as the correspondent of the 'Warder' must have seen it on the opposite side of the place where it had been vertical from what we did :

Belfast, 12th October, 1840.

SIR,-I had the pleasure also of seeing this phenomenon the same time as Correspondent. I was about 5 miles on this side of Dublin when it happened.-Yours, &c., JOSEPH HILL, Mail Guard.

'Extraordinary Appearance in the Sky.-(From a Correspondent.)-About a quarter before ten o'clock on Wednesday, at an immense altitude, a white ball of fire appeared in the north-eastern part of the sky for a moment, and shot downwards, illuminating the whole heavens, and causing an extraordinary sensation in those who witnessed it before its descent. The ball was tinged with a beautiful violet blue.'-From the 'Warder' of Saturday, October 10, 1840."

On some Points in the Anatomy of the Araneidea, or true Spiders, especially on the internal structure of their Spinning Organs. By R. H. MEADE, F.R.C.S.

[A Communication ordered to be printed entire among the Reports.]

It is not my intention in the present communication to enter generally into the anatomy of spiders, but to confine myself to an account of the arrangement and structure of the parts contained in the abdomen; and more especially to describe the glandular organs by which the silk forming their webs, is secreted.

I was led to undertake this investigation by the hope that an accurate examination into the minute anatomical structure of the spinning organs might clear up some important differences of opinion as to their functions. Martin Lister, Cuvier and others, contend that spiders have the power of forcibly ejecting the fluid which forms the silk from their spinnerets; and are thus able to propel a thread to a considerable distance, and in any direction. Both the above-named naturalists state that they have distinctly seen them shoot out their webs, but Mr. Blackwall (the greatest living authority on Arachnology) denies that they have any such power, and says that the tenacious fluid is simply emitted from the extremity of the abdomen by pressing it against some fixed point, and then drawn out into a thread by a current of air, and wafted to some neighbouring object to which it adheres, or left floating in the atmosphere. Should my researches fail to clear up this interesting question, they may tend to elucidate some other curious points connected with the functions of the spinning organs, such as the power which spiders have of forming different kinds of threads from the same spinnerets, some of which are adhesive, while others have no viscidity, but simply form a framework to support the others.

I met with considerable difficulties in the course of my investigations, had to make numerous dissections, and at last was unable to arrive at satisfactory conclusions on many points; for the organs are so small and delicate, and become so brittle when the spiders have been preserved any time in spirits, that it is not easy to separate them. My plan has been to dissect carefully in water or spirit, under a simple lens, and then to submit each portion separately to the action of a compound microscope.