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dern. We have laboriously endeavoured to trace the extraordinary life of a poet, whose misfortunes add a melancholy interest to his writings.

Forcible, though minute, as a painter of domestic and of rural scenery a keen observer of character, and an affecting moralist,-Cowper, in his versification, is usually harsh. We are neither lulled by the melting euphony of Pope, nor elevated by the sonorous magnificence of Milton. Violent contrasts frequently recur. The burlesque and the solemn clash together, unharmonised by intermediate chords.

At the conclusion of these volumes, Mr. Hayley proposes that a monument in the metropolis should be raised to Cowper, from funds to arise in part by public contribution, and in part by the profits of an edition of Milton, with translations of his Italian and Latin poems, decorated with plates. These decorations, we hope, will exceed in merit the portraits introduced into the work before us. The first engraving is discreditable to the taste of the artist: the head from Lawrence is of moderate execution; and the portrait of Cowper's mother would disgrace an engraver's apprentice.

It remains for us to appreciate the merits of Mr. Hayley as a biographer. Allowing for the partiality of friendship, he has discharged his duty in a respectable manner. His compilation, however, is too diffuse: his materials are loosely arranged; and his style, sometimes elegant, is often languid and verbose, charged with epithets, and sullied by affectation.

The distressing insanity of a friend should be revealed in the language of feeling rather than of art. 'The calamitous eclipses of his effulgent mind' we select from other artificial phrases, in which we can discover no graceful propriety.

ART. II.-Philosophical Transactions of the Royal Society of London. For the Year 1802. Part II. 4to. 17s. 6d. sewed. Nicol. 1802.

WE hasten to overtake this interesting annual publication, which has, on several accounts, been too long delayed. We shall not, however, detain the reader by apologies, or a tedious introduction. The different articles are too valuable to require any assistance from our comments.

• Observations on the two lately discovered celestial Bodies. By William Herschel, LL. D. F. R. S.'

We have already announced these two new planets, discovered by MM. Piazzi and Olbers, and have remarked their appropriate situation in a place where there was a considerable

chasm in the planetary system, as well as their disproportioned size to the other planets. We, some time since, suggested, that they were perhaps comets brought into less eccentric orbs, by the joint attractions of Jupiter and the sun; and our author's observations seem to confirm the suspicion. From these observations, the diameter of Ceres seems scarcely to exceed 160 miles, and that of Pallas, taking the mean of two measures, about 130 miles. If we compare them with the planets, we shall find that-

1. They are celestial bodies, of a certain very considerable size. 2. They move in not very eccentric ellipses round the sun. 3. The planes of their orbits do not deviate many degrees from the plane of the earth's orbit.

4. Their motion is direct.

5. They may have satellites, or rings.

6. They have an atmosphere of considerable extent, which however bears hardly any sensible proportion to their diameters.

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7. Their orbits are at certain considerable distances from each other.

Now, if we may judge of these new stars by our first criterion, which is their size, we certainly cannot class them in the list of planets: for, to conclude from the measures I have taken, Mercury, which is the smallest, if divided, would make up more than 135 thousand such bodies as that of Pallas, in bulk.

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In the second article, their motion, they agree perhaps sufficiently well.

The third, which relates to the situation of their orbits, seems again to point out a considerable difference. The geocentric latitude of Pallas, at present, is not less than between seventeen and eighteen degrees; and that of Ceres between fifteen and sixteen; whereas, that of the planets does not amount to one half of that quantity. If bodies of this kind were to be admitted into the order of planets, we should be obliged to give up the zodiac; for, by extending it to them, should a few more of these stars be discovered, still farther and farther deviating from the path of the carth, which is not unlikely, we might soon be obliged to convert the whole firmament into zodiac; that is to say, we should have none left.

In the fourth article, which points out the direction of the motion, these stars agree with the planets.

With regard to the fifth, concerning satellites, it may not be easy to prove a negative; though even that, as far as it can be done, has been shewn. But the retention of a satellite in its orbit, it is well known, requires a proper mass of matter in the central body, which it is evident these stars do not contain.

The sixth article seems to exclude these stars from the condition of planets. The small comas which they shew, give them so far the resemblance of comets, that in this respect we should be rather inclined to rank them in that order, did other circumstances permit us to assent to this idea.

In the seventh article, they are again unlike planets; for it ap pears, that their orbits are too near each other to agree with the ge

neral harmony that takes place among the rest; perhaps one of them might be brought in, to fill up a seeming vacancy between Mars and Jupiter. There is a certain regularity in the arrangement of planetary orbits, which has been pointed out by a very intelligent astrono mer, so long ago as the year 1772; but this, by the admission of the two new stars into the order of planets, would be completely overturned; whereas, if they are of a different species, it may still remain established.' P. 224.

This reasoning is, however, too rigorous. By a similar argument, it might be contended that there should be no more than seven planets, seven colours, &c.: to which we may add, that the vacant space may be as aptly filled by two smaller bodies as by one larger. Had we found a large planet, three times the united diameter of the two now under our eyes, we should not have contested its title; and we see not, as we shall presently show, that we ought, from any considerations, to combat the claim of either Ceres or Pallas. The other objection is still weaker. If we admit bodies, it is said, of such great geocentric latitudes, we must resign the zodiac. But what power fixed its limits?-the motions of planets, which did not wander beyond it; and now some more eccentric are found, its limits must be, for the same reason, extended. If, however, these bodies be not planets, we may ask, What are they? We know only of three kinds of celestial bodies; planets revolving about the sun, deriving their light from it, with a determined annual parallax, and a diameter subtending a sensible angle; fixed stars shining with a light peculiarly their own, without any parallax, and subtending no sensible angle; and comets, deriving their light from the sun, which they seem to convey in a peculiar form, that of a coma, and a tail projected in a direction opposite to the sun, with a very considerable geocentric latitude-in other words, moving in a plane greatly inclined to that of the earth's orbit. Ceres and Pallas are certainly observed with come: are they not, therefore, comets?-Let us attend to our author.

1. They are celestial bodies, generally of a very small size, though how far this may be limited, is yet unknown.

2. They move in very eccentric ellipses, or apparently parabolic arches, round the sun.

3. The planes of their motion admit of the greatest variety in their situation.

4. The direction of their motion also is totally undetermined. 5. They have atmospheres of very great extent, which shew themselves in various forms of tails, coma, haziness, &c.

'On casting our eye over these distinguishing marks, it appears, that in the first point, relating to size, our new stars agree sufficiently well; for the magnitude of comets is not only small, but very unliCRIT. REV. Vol. 38. May, 1803.


mited. Mr. Pigott's comet, for instance, of the year 1781, seemed to have some kind of nucleus; though its magnitude was so ill defined, that I probably over-rated it much, when, November 22, 1 guessed it might amount to 3 or 4" in diameter. But, even this, considering its nearness to the earth, proves it to have been very small.

That of the year 1783, also discovered by Mr. Pigott, I saw to more advantage, in the meridian, with a twenty-feet reflector. It had a small nucleus, which, November 29, was coarsely estimated to be of perhaps 3" diameter. In all my other pretty numerous observations of comets, it is expressly remarked, that they had none that could be seen. Besides, what I have called a nucleus, would still be far from what I now should have measured as a disk; to constitute which, a more determined outline is required.

i In the second article, their motions differ much from that of comets; for, so far as we have at present an account of the orbits of these new stars, they move in ellipses which are not very eccentric.

Nor are the situations of the planes of their orbits so much unlike those of the planets, that we should think it necessary to bring them under the third article of comets, which leaves them quite unlimited.

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In the fourth article, relating to the direction of their motion, these stars agree with planets, rather than with comets.

6 The fifth article, which refers to the atmosphere of comets, seems to point out these stars as belonging to that class; it will, however, on a more particular examination, appear that the difference is far too considerable to allow us to call them comets.' p. 226.

In fact, the smallest coma of a comet exceeds that of Ceres or Pallas above a hundred times; and neither moves in orbs even approaching the eccentricity of a parabola, or is distinguished by a tail. It is also highly probable that the nuclei of comets are very small: they never disturb the planetary motions, though often disturbed by them.

Why then are not these bodies planets? We see no reason for any distinction: they revolve round the sun, and are not comets. We must discover another system, before we are allowed to change the appellation. Mr. Herschel would call them asteroids; but he labours for a distinction, which, in the end, will fail him.

I shall now give a definition of our new astronomical term, which ought to be considerably extensive, that it may not only take in the asteroid Ceres, as well as the asteroid Pallas, but that any other asteroid which may hereafter be discovered, let its motion or situation be whatever it may, shall also be fully delineated by it. This will stand as follows.

Asteroids are celestial bodies, which move in orbits either of little or of considerable excentricity round the sun, the plane of which may be inclined to the ecliptic in any angle whatsoever. Their motion may be direct, or retrograde; and they may or may not have considerable atmospheres, very small comas, disks, or nuclei.

As I have given a definition which is sufficiently extensive to take in future discoveries, it may be proper to state the reasons we have for expecting that additional asteroids may probably be soon found out. From the appearance of Ceres and Pallas it is evident, that the discovery of asteroids requires a particular method of examining the heavens, which hitherto astronomers have not been in the habit of using. I have already made five reviews of the zodiac, without detecting any of these concealed objects. Had they been less resembling the small stars of the heavens, I must have discovered them. But the method which will now be put in practice, will completely obviate all diffculty arising from the asteroidical appearance of these objects; as their motion, and not their appearance, will in future be the mark to which the attention of observers will be directed.' P. 229.

We shall not extend our article by enlarging on our own original idea, that these bodies may have been comets constrained to revolve within less eccentric orbits; because, in reality, we know little of the nuclei of comets, and have no criterion by which we can measure their density, nor indeed, very correctly, their diameters. The suspicion may remain on record, to be tried by future observations, with little solicitude, in the author, respecting its truth or fallacy.

IX. Description of the Corundum Stone, and its Varieties, commonly known by the Names of Oriental Ruby, Sapphire, &c.; with Observations on some other mineral Substances. By the Count de Bournon, F. R. S.'

The count de Bournon has considerably enlarged our views in mineralogy, by tracing the adamantine spar in a great variety of precious stones. In fact, it is the basis of all that are styled Oriental-an appellation not perhaps exclusively confined to the country which offers them to our notice, but attributed to gems of a peculiar hardness: yet it will appear that these are generally of eastern origin. Our author describes the corundum somewhat too diffusely. The imperfect, which seems divided into lamina, is of a greyish colour, and is found in the Carnatic. This is less hard than the more perfect coloured stones, which scarcely yield to the diamond in this respect. The red Oriental ruby is very hard, but somewhat exceeded by the sapphire.

This substance emits pretty bright sparks, when struck with a piece of steel; but they are by no means proportioned to its hardness. If a piece of flint be struck with the same force, the sparks it produces are more numerous, as well as more bright; and it is possible to obtain sparks from flint, by a very slight blow, such as would not be sufficient to produce them from perfect corundum. It is also necessary, in order to obtain sparks from corundum, that the stone should have pretty sharp edges: if the part that is struck is obtuse, it is with some difficulty that any sparks can be obtained. The imperfect corundum, however, has, in this respect, some advantage over the perfect kind.' r. 249.

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