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is a major-general too, and always dresses in his uniform, which still increases the resemblance. Every time I see him, he says or does something that recalls strongly to my mind the idea of our noble general. He laughs at the follies of his country, and holds these wretched prejudices in that contempt they deserve. “ What would the “ old hardy Romans think (said he, talking on “ this subject) were they permitted to take a view “ of the occupations of their progeny ? I fould “ like to see a Brutus or a Cassius amongst us 6 for a little ; how the clumsy vulgar fellows 6 would be hooted. I dare say they would soon “ be glad to return to the shades again.”
Adieu ; for some nights past we have been observing the course of a comet; and as we were the first people here that took notice of it, I assure you, we are looked upon as very profound astronomers. I shall say more of it next letter. We have now got out of our abominable inn, and. have taken a final leave of our. French landlady. The Count Bushemi, a very amiable young man, has been kind enough to provide us a lodging on the sea-shore; one of the coolest and most agreeable in Palermo.
Ever yours; &c.
L È T T E R XXVI.
Palermo, July 2d.
OUR comnet is now gone ; we first observed it on the 24th. It had no tail, but was furrounded with a faintish ill defined light, that made it look like a bright star shining through a thin cloud. This in all probability, is owing to an atmosphere, around the body of the comet, that causes a refra&tion of the rays, and prevents them from reaching us with that distinctness we observe in bodies that have no atmosphere. We were ftill the more persuaded of this two nights ago, when we had the good fortune to catch the comet just passing close by a small fixed. star, whose light was not only considerably dimm’d, but we thought we observed a sensible change of place in the star, as soon as its rays fell into the atmosphere of the comet; owing no doubt to the refra&tion in passing through that atmosphere. We attempted to trace the line of the comet's course, but as we could find no globe, it was not possible to do it with any degree of precision. Its direction was almost due north, and its velocity altogether amazing. We did not observe it so minutely the two or three first nights of its appearance, but on the 30th it was at our zenith here, (latitude 38° 10°;, longitude from Lond. 139) about five minutes after midnight, and last night, the first of July, it passed four degrees to the caft of the polar star, nearly at 40 minutes after eight. So that, in less than 24 hours, it has described a great arch in the heavens, upwards of so degrees; which gives an idea of the most amazing velocity. Supposing it at the distance of the sun, at this rate of travelling, it would go round the earth's orbit in less than a week. Which makes, I think, considerably more than sixty millions of miles in a day; a motion that vastly surpasses all human comprehension. And as this motion continues to be greatly accelerated, what must it be, when the comet approaches still nearly to the body of the sun! Last night a change of place was observable in the space of a few minutes, particularly when it passed near any of the fixed stars. We attempted to find if it had any observable parallax, but the vast rapidity of its motion always prevented us; for whatever fixed stars it was near in the horizon, it had got so far to the north of them, long before it reached the meridian, that the parallax, if there was any, entirely escaped us.
I shall long much to see the observations that have been made with you, and in other distant countries, on this comet; as from these, we shall probably be enabled to form some judgment of its distance from the earth; which, although we could observe no parallax, I am apt to believe .-was not very great, as its motion was so very perceptible. We could procure no instruments to measure its apparent distance from any of the fixed stars, so that the only two observations any thing can be made of, are, the time of its passing the polar star last night, its distance from it, and the time of its arrival at our zenith on the 30th ; this we found by applying the eye to a straight rod, hung perpendicularly from a small thread. The comet was not in the exact point of the zenith, but to the best of our observation, about fix or seven minutes to the north of it. Last night it was visible almost immediately after sunfet; long before any of the fixed stars appeared. It is now immersed in the rays of the sun, and has certainly got very near his body.
If it returns again to the regions of space, it will probably be visible in a few days, but I own I should much doubt of any such return, if it is really by the attractive force of the sun, that it is at present carried with such amazing celerity towards him. This is the third comet of this kind, whose return I have had an opportunity of watching; but never was fortunate enough to find any
of them after they had passed the fun; though those that do really return, appear at that time much more luminous than before they approached him.
The astronomy of comets, from what I can remember of it, appears to be clogged with very
great difficulties, and even fome seeming absurdities. It is difficult to conceive, that these inmense bodies, after being drawn to the sun with the velocity of a million of miles in an hour; when they have at last come almost to touch him, fhould then fly off from his body, with the same velocity they approach it, and that too, by the power of this very motion that his attraction has occafioned. The demonstration of this I remember is very curious and ingenious; but I wish it may be entirely free from sophistry. No doubt, in bodies moving in curves round a fixed centre, as the centripetal motion increases, the centrifugal one increases likewise; but how this motion, which is only generated by the former, should at last get the better of the power that produces it, and that too, at the very time this power has acquired its utmost force and energy; seems somewhat difficult to conceive. It is the only instance I know, wherein the effect increasing regularity with the cause ; at last, whilst the cause is still a&ing with full vigour; the effect entirely gets the better of the cause, and leaves it in the lurch. For, the body attracted, is at last carried away with infinite velocity from the attracting body. By what power is it carried away? Why, say our philosophers, by the very power of this attraction, which has now produced a new power superior to itself, to wit, the centrifugal force. However, perhaps, all this may be reconcilable to reason; far be it from