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As it is, and under no fuch apprehenfions, we part with him with regret; and were not his abfence the time for repofe, and repose indifpenfable to our wearied nature, we should never willingly forego the light of the Sun: Very justly, therefore, may he claim pre-eminence in our esteem, and the first engagement of our thoughts; accordingly, I mean, at this time, to request your attention, LADIES and GENTLEMEN, to a few remarks on the folar luminary.

That circumftance which, in the first place, distinguishes the Sun from every object around us, is his LIGHT; this first ftrikes us, and is fo neceffary, and pleasant to us, and so peculiar to this heavenly orb, that we pity those eyes that never

beheld the Sun.

It is natural, therefore, to inquire of what is this fountain. and fource of light composed? In reply to which question, I beg leave to premise, (1) that we have nothing on earth, in any degree, comparable to it, fo as to determine its properties by comparison; for as our earth is an opaque body, void of native light, it affords no example perfectly applicable; (2) what we call fire, or light, what fire or light we on earth may be fuppofed to poffefs, is not elementary, but grofs, terrestrial, and impure, even after we have made every allowance and diftinction between fuel and fire; therefore, (3) that we can only conjecture on this fubject, and fupport our conjectures by the analogy of fuch substances or circumftances as come under our examination.

We may conceive of any matter whatever as either a folid, or a fluid. Solidity, you know, LADIES and GENTLE

MEN, is such a fixity of parts, as does not permit the motion of one over others: You cannot, in pushing a folid body, pufh what parts of it you pleafe, but muft, of neceffity, push from you the whole of fuch a body; whereas, of a fluid, you may roll over and over again, may difplace and remove, any of its parts: As in water, you may agitate the furface without moving the bottom; you may even furrow one part of it, and yet a diftant part be unaffected. By the bye, we are apt, when we instance a fluid, to take up the idea of water, that fluid being our most intimate acquaintance: we ought rather to recollect that there are fluids of much greater weight and compactness (fubftance fhall I call it?) than water; oils we know are fo, quickfilver, or mercury, we know is fo (fourteen times heavier than water), and continuing this progrefs, we may easily conceive of a fluid extremely denfe and fubftantial, and yet permitting a motion of a part or parts of its quantity without disturbing the reft; whereby it will ever be diftinguished from a folid.

Of fome fuch fluid the Sun is prefumed to be compofed; a close, adhesive fluid of light; a confolidated fluid is, I acknowledge, an improper expreffion, yet it may ferve to impart an idea of a fluid fo compreffed, fo united, as to leave fcarce any vacancy between its component particles; confequently, the fame extent of space may contain a very great many more of fuch particles, than if they were loose, and at a distance, or separated, in any degree, from each other; we will only fay at prefent ten times as many; confequently alfo, if any given number of particles be fuppofed to quit this incorporated

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affemblage, in a given time, it will be ten times as long before fuch a compreffed body is exhausted.

A fluid may be thought more easily acted upon than a solid, its parts more easily separable, and, when separated, more divergent: Water is easily acted on; the very paffage of the air over it, deprives water of fome of its particles, and its vapours spread every way; very evidently, much further than duft, or any fimilar substance, flies from a folid body. The fluid, therefore, of which the Sun is compofed, is adapted to give off its particles; but, in order to improve this difpofition of the Sun to give off its particles, in order to impel these particles with vigour fufficient to quit the main body, to which they naturally adhere, and by which they are attracted, and held, there must be fome force used, fome active and vigorous motive muft drive them from their native abode; and this impulse we find in a ROTATION of the folar orb upon its proper

axis.

Give me leave here to remind you, LADIES and GentleMEN, that however adapted may be our visual powers to the nature of the globe we inhabit, yet, we must not expect to find them competent to the examination of diftant worlds; on the contrary, they often deceive us, and generally, perhaps always, fail in their information. It is true, the Sun feems round; his outline, I fay, is round, yet, for aught we know, that part of him, which more immediately faces us, might be flat he might resemble a very large dish set at a distance, and be merely a flat body of a certain thickness, without any revolutory motion. I freely confefs, I think, that had he

been

been fo, we should have had little occafion to thank him for his refplendence; it is exceedingly probable we should scarce have feen him. But, if we fuppofe him a globe, and revolving on his axis, we suppose a power which caufes inceffant agitation and motion (among his exterior particles efpecially), and which by its conftant and perpetual activity, Shoots his luminous beams every direction around him.

in

[The fun revolves about his axis in twenty-five days, fifteen hours, fixteen minutes.]

Let me here observe, that of all matter hitherto known or examined, light is compofed of the smallest particles; they are the most minute and atomical: and of all globes hitherto explored, the fun is immenfely the largest and most capacious, being 793,000 miles in diameter; his fuperficial contents 10,000 times the furface of the earth: a momentary reflection is fufficient to evince, that the rapid revolution of a globe so prodigious, must have most powerful effect upon particles fo diminutive; it must hurl them through every space of free ethereal medium, and nothing can obftruct their progress, but fuch opaque and folid bodies as forbid their penetration. Yet even by them they fcorn to be confined, and rebound, diverging every way; fuch reflected light it is which shews us the moon, and the planets of our fyftem, they stopping the paffage of fo great a quantity of light, that even when reflected on all fides, it is fenfible through a very extensive distance.

I request the attention of my auditory to what I just hinted of the MAGNITUDE of the fun; and, as closely connected with it, his SITUATION in the fyftem. I may here obferve, that according

No. 2.

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according to the advances of fcience, the magnitude of this luminary is calculated proportionally greater than formerly; which proves, not that former principles were erroneous, but that they were not perfected by fuch accuracy and advantages, as modern times poffefs.

The folid bulk of the fun is eftimated at one million times the folid bulk of the earth; his furface, at ten thousand times the furface of the earth; his diameter, feven hundred ninetythree thousand miles.-Dimenfions worthy our admiration! It seems at first fight, as if here was a waste, a redundance: might not a fun of lefs magnitude have fufficed, have equally difpenfed its beams, excited heat, and have been equally bene→ ficial? Light and heat a fun of smaller magnitude might have communicated; but it would not therefore have been equally beneficial. Recollect what was just now remarked of the impulfe of light; fmaller dimenfions muft imply smaller pow er. Besides this, modern difcovery affords a fatisfactory anfwer to the question, having demonftrated, that all large bo dies attract fmaller; that all fmall bodies gravitate toward larger; that the more are the contents of a large body (i. e. the more compact, clofe, and denfe its particles), the greater is its attractive power; it follows, that a fun of diminished magnitude would have been proportionally weakened in its effects on furrounding bodies. We will fuppofe, if you please, that the fun were fuddenly fhrunk to the dimenfions of our earth; the order of the heavens would ceafe, the fun would be drawn from his ftation, and the larger bodies around him would attract him toward themfelves. Shall we add to the fuppofition,

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