to be a corruption of the term legion. The objections we shall transcribe.

The facts which I am about to state in evidence are these: In the first place, the Welsh term used for a legion is lleng, a very common word in all the writings of the different ages; therefore, if the foregoing derivation were true, the name of the town would have been Caer Lleng; and which a critic, nay every body who knows the Welsh language, can point out to be very different in structure from Caer Lleon, a word of three syllables. The next fact is, that the proper name of the town is Caer Llion, and not Caer Lleon; and it is always found so in our most ancient manuscripts. The meaning of caer is already well known to be any inclosure of defence, or fortification, and in a secondary sense a city.

I shall proceed to state, as a third fact, the import of lion to be, streams, torrents, or floodings-a term often used, in an aggregate sense, for any great body of water; and it is derived from lli, which is the singular form of the word, implying a stream or flood, in its popular acceptation. The last fact to be adduced is, the great propriety of the name for the situation of the town on the banks of the river Usk; and probably the situation is, or was formerly, on the extremity of the range of the tides; thus rendering the plural form of the appellation still more descriptive, than if it were only (as it frequently has been used) on account of the vicinity of the river Usk to the town. As to the last-mentioned circumstance you are fully enabled to judge for yourself, which renders it needless for any remarks of mine; and as I have laid down the leading points, which make me dissent from the commonly-received etymology of Caerleon, I commit them in this brief way to your judgement, to draw such an inference as may seem consistent with reason.' P. 417.

The population of Abergavenny is said to exceed two thousand souls. The other numbers of the appendix do not admit of an abstract, or require a more particular notice.

ART. XI.-Philosophical Transactions of the Royal Society of London. For the Year 1801. Part II. 17s. 6d. sewed. 4to. Payne.

• XII. A HISTORICAL and Anatomical Description of a doubtful amphibious animal of Germany, called by Laurenti, Proteus Anguinus. By Charles Schreibers, M.D. of Vienna. Communicated by the Right Hon. Sir Joseph Banks, Bart. K.B. P.R.S.'

Dr. Schreibers seems greatly inclined to consider this animal as a perfect one, since, as he observes, there is none found in the lakes of Carniola of which it can be the larva. Naturalists well know that fishes and reptiles are distinguished as they breathe by gills or by lungs. Many years since an animal was found which had both these organs of respiration; and Linnæus.

formed a new order for its reception. Many similar ones have been since discovered: yet, as the first is probably only the larva of a more perfect animal, doubts have arisen respecting the rest. The siren lacertina is consequently removed to fishes under the genus murana, and no naturalist has yet dared to reestablish the new order. Scopoli undoubtedly thought it a peculiar genus (genus singulare, Ann. Hist. Natur. quintus, p. 74, 75), and Laurenti conceived the same. Linnæus saw only a drawing of it, and did not hesitate.' He at once decided it to be the larva of a lizard. Hermann and Schneider have adopted the same opinion, and we shall add our own reasons for following them. It must be indeed admitted that every argument on this side should be received with caution, for nature is progressive by gradual shades; and it is, a priori, more probable that animals should have been formed with both gills and lungs, than that there should be a chasm of such extent. The great question however must be, whether the present animal be of this kind?

،

We think it an imperfect one, because of its regular periodical appearance; and, though the size varies, this must be the case with larvæ of every kind, whose growth is progressive, before their change takes place. At this period too they are usually very voracious, and the proteus anguinus is remarkably so. Another discrimination of an early period is the size of the liver; to which we may add the absence of the organs of generation; for though Dr. Schreibers have described two bladders, which he calls ovaries, there is no reason assigned for considering them as such. His great argument is, that no animal is found in these lakes of which it can be the larva. This however is far from conclusive. Perfect animals are often very distant in form and appearance from larvæ. He himself allows that all the lakes of Carniola communicate by subterraneous passages; and the more perfect animal may reside in the deepest parts, where it is less subject to storms, or be strong enough to resist their power. The anatomical description is curious; and in the specimens which our author examined he discovered eyes, which were formerly supposed to be wanting. The organ however only exists. We do not know that the animal has the sensation of sight.

• XIII. Observations tending to investigate the Nature of the Sun, in order to find the Causes or Symptoms of its variable Emission of Light and Heat; with Remarks on the Use that may possibly be drawn from Solar Observations. By William Herschel, LL.D. F.R.S.'

XVI. Additional Observations tending to investigate the Symptoms of the variable Emission of the Light and Heat of the Sun; with Trials to set aside darkening Glasses, by transmitting the Solar Rays through Liquids; and a few Remarks

to remove Objections that might be made against some of the Arguments contained in the former Paper. By William Herschel, LL.D. F.R.S.'

These, like the rest of Mr. Herschel's papers, are curious— we had almost said singular; and in these, perhaps, he has more freely indulged his imagination than in any former ones.

do not object to an hypothesis to illustrate facts, nor indeed as a standard to which they may be brought to ascertain the truth or falsehood of the system; and Mr. 'Herschel scarcely aims at more, though he carries his illustrations somewhat farther than facts will support him.

The various modifications of the sun's light are distinguished into openings, shallows, ridges, nodules, corrugations, indentations, and pores.' It is enough for us to remark, that the sun's light is either defective or in excess. The two first are

of the former kind, differing in degree; and the two last are similar, but limited in extent, and differing a little in form. The third, fourth, and fifth, are of the latter class, and the forms are sufficiently discriminated by the appellations. We must detail the author's system in a synthetic form.

In some prior papers, Mr. Herschel has advanced the opinion, that the sun is an opaque body of a planetary nature, admitting of habitation, and probably inhabited. The luminous matter he supposes to be separated from the body, and the light evolved in the higher regions of its atmosphere. The sun, he thinks, has an atmosphere more dense than ours, in consequence of the increased gravitation towards so vast a mass. This atmosphere, whose density is augmented by clouds, is illuminated and seen, by us, in the shallows, from the reflected rays, while we perceive the body of the orb itself in the openings' or spots.' There must be a cause then which separates the atmospheric clouds and the luminous fluid above, so as to discover the substance of the planet. This cause, if we rightly understand our author, is the emission, of an elastic gas from the sun itself, from which the luminous matter is derived, while the power of this gas is not sufficient, when emitted with less force, to separate the clouds and render the body of the sun visible. Thus spots are connected with the ridges, &c. and the apparent want of light is the means of its accumulation. Ridges, nodules, and corrugations, are consequently the marks of accumulated light, and originally derived from the sun, through the vacuities called spots. On examination with the photometer, the surface of the atmosphere reflected 469 rays, and the body of the sun 7 only, when the luminous surface gave 1000.

When we speak of the sun's atmosphere below the luminous fluid, we must be supposed to mean the region of clouds; for our author, thinks there may be a clear atmosphere far above

the body of the sun, to the extent of some hundreds of miles; and, in reality, we must be supposed to view the body of the sun only through its atmosphere, which our author thinks to be transparent.

We have not given Mr. Herschel's system in his own words, because we have been able to compact it better, and to separate it from the observations. To those, however, who wish to examine it critically, we would recommend the paper itself.. We must add, that the author suspects the sun to be less perfectly luminous on one side than on the other; so that to an observer in another system he would appear to be a star, having periodical variations of light.

but

All this, it may be said, is hypothetical:-it is indeed so; it quadrates well with the appearances, and may rest as an hypothesis till other observations confirm or destroy it. Mr. Herschel however builds on it a superstructure, perhaps more hypothetical still. We have remarked that the accumulated light of the sun, according to our author, is connected with its spots, as the channels through which the matter affording light is derived; and that therefore, from the previous spots, fertile seasons may be predicted. He endeavours to establish this by evidence which we think very vague, viz. the average price of wheat in periods subsequent to those distinguished by numerous spots-the causes of and accumulations of light. He seems to think, that when spots have preceded, the seasons have been more genial and fertile. The evidence for this opinion must however be necessarily inconclusive and unsatisfactory. He speaks of proving it also by the meteorological register of the Royal Society, and he will prove it in this way; for the morning observation is, as we have often observed, affected by the sun's rays, and consequently the highest degree is too great. What then arises from the sun will easily appear to be owing to it. If he adopt the afternoon heat, he will be nearer the truth.

XXI. A Continuation of the Experiments and Observations on the Light which is spontaneously emitted from various Bodies; with some Experiments and Observations on Solar Light, when imbibed by Canton's Phosphorus. By Nathaniel. Hulme, M.D. F.R.S. and A.S.'

We step on to this article as to a kindred subject, though not very nearly connected with the experiments of Mr. Herschel. Dr. Hulme in this continuation,' first examines the effects of different aërial fluids on the spontaneous emission of light. Herrings and other animals, which contain light as a component part, do not, in our author's opinion, emit it, except when exposed to the air. His experiments are not however perfectly conclusive; for the bodies placed in contact with the

luminous ones are themselves capable of imbibing light, and therefore, though emitted, it may not be visible, as it is again absorbed. It is better ascertained that the blast of a pair of bellows does not increase the emission of light;-perhaps it could not have been expected. Oxygen gas rendered the light somewhat more vivid than common air, though but slightly so. Azotic gas either prevented the emission of light, or extinguished it: yet the light was preserved in this gas when previously fixed on a cork. This is by no means so remarkable as the author supposes: it may prevent the separation by impeding or checking the decomposition, while it does not effect the light already separated.

Hydrogen and carbonic acid and gas not only prevent the emis-, sion of light, but extinguish it. Yet the light is not destroyed, for it again appears when exposed to the air of the atmosphere. Sulfurated hydrogen gas is more powerful in its action of extinguishing light, which returns also more slowly in open air. Nitrous gas is more powerful still; and the light, except from the glow-worm, could not be re-produced. A vacuum destroyed light, which the return of air re-illumined.

The next section is on solar light, imbibed by Mr. Canton's phosphorus. Moderate heat rendered the light more vivid, but increased heat extinguished it. Dr. Hulme however, in no part of this paper, considers the light as occasioned by decomposition. He should have pointed out, that, in the latter case, the emission of light was at first extraordinarily vivid. In fact, the heat hastened the complete decomposition, and did not, strictly speaking, extinguish the light. He should have remarked also, that phosphorus, kept in a dark state, loses all the light that can be spontaneously emitted. It requires the assistance of heat to separate more. The solar light, imbibed by the phosphorus, is subject to the influence of heat and cold, like the light from rotten wood, glow-worms, and fishes. It remains to be inquired, whether it be affected in the same manner by different gasses?

< XIV. Observations on the Structure, and Mode of Growth, of the grinding Teeth of the Wild Boar, and Animal incogni tum. By Everard Home, Esq. F.R.S.'

Mr. Home having explained the structure of the molares of the elephant and sus Ethiopicus, was led to inquire whether the same structure were observable in the other species of sus. He was disappointed, seemingly, because the age of the animals was not mature enough for the production of the second set of teeth. In the wild boar, which had attained a more mature period, he found a similar formation. In the elephant, the sus Ethiopicus, and the wild boar, only, is found this extension of the masticating surface of the grinding teeth. In these also