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TNOW came still evening on, and twilight gray
how beautiful is night ! Southky.
[After reviñng and enla the English Lex4. or o g ex
when scaliger, whole years of labour past, Beheld his Lexicon complete at last, And weary of his task, with wond'ring eyes, saw from words pil'd on words a fabrick rise, He curs'd the industry, inertly strong, in creeping toil that could perfia so long, And if, enrag’d he cried, Heav'n meant to shed its kcenest vengeance on the guilty head,
For the Anthology.
The drudgery of words the damn'd would know,
Yes, you had cause, great Genius, to repent ;
Yet warn'd by mc, ye pigmy wits, beware,
A mind like Scaliger's, superiour still,
My task perform'd, and all my labours o'er,
Where Comus revels, and where wine inspires,
* See Scaliger's epigram on the same subjećt, communicated, without doubt, by Dr. Johnson, Gent. Mag. 1748, p. 8.
WRITTEN AT SUNSET.
Ere long shall night assume her sway,
And thus the transient joys of life
H------, April, 1806.
DoRINDA's sparkling wit and eyes,
which blazes high, but quickly dies,
Love is a calmer, gentler joy,
Librum tuum legi & quan diligentissime potul annotavi, Quae commutanda, quae eximenda, ar
bitrarer. , Nam ego dicere verum assuevi. maxime laudari merentur.—Pliny.
Neque ulli patientius reprehenduntur quam qui
ARTICLE 1. [Concluded.]
Memoirs of the American Academy of Arts and Sciences. Vol. I. 1805. 4to. pp. 564.
I. Observations usion an hysiothesis for solving the fihenomena of light, with incidental observations, tending to shew the heterogeneousness of light, and of the electrick fluid, by their intermirture, or union, with each other. By James Bowdoin, Esquire, President of the .Mmerican Academy of Arts and Sciences.
The celebrated Dr. Franklin observed, that he was much in the dark about light. And it must be acknowledged, that, notwithstanding the great progress we have made in opticks, many difficulties still remain relative to the nature of light, or the manner in which vision is produced. It is well known, that modern philosophers have proposed two hypotheses for the purpose of explaining this point. In one, adopted by Huygens, Euler, and some others, an extremely subtile, elastick fluid is supposed to penetrate all bodies, and to fill all space; and vibrations,being excited in it by the action of luminous bodies, are propagated to the eye, and produce in that organ the sensation of vision in the same manner, as pulsations of air produce in the organ of hearing the sensation of sound. According to the other
PHYsic AL PAPERs.
hypothesis, maintained by Sir Isaac Newton and others, light consists of particles of matter, extremely minute, which being projected or thrown off from luminous bodies in every direction by a repulsive force, and reflected by opaque bodies, produce the sensation of vision by impulse on the eye. The hypothesis, on which the author of this Memoir remarks, is
contained in some queries, propos
ed by Dr Franklin, and is in substance the same as the former of the two preceding ; to which the observations may be considered as objections, or arguments in favor of the other. In one part of the reasoning in form of queries relative to the production of light in various instances by motion, on supposition that the hypothesis of vibration is true, more seems to be assumed than is granted in the hypothesis. It does not appear to be inferable from Dr. Franklin's statement, nor from any other, that we recollect to have seen, that every kind and degree of motion in the elastick fluid is supposed or admitted to be productive of the sensation of vision ; nor does this seem to be a necessary consequence. In the theory of sound, though the vibratory agency of the air is clearly ascertained, yet it is not supposed that every kind and degree of motion in the air produces the sensation of sound. The author's ideas respecting the heterogeneousness of light and *
of the electrick fluid may be well learned from the following extract, it being noted, that he uses fire in it as synomimous with light. “Electricity and fire differ in many respect... and in some they agree ; as hath been shewn in Dr. Franklin's letters on electricity. So far as they agree in their effects, their nature may be presumed to be alike : or rather, from that agreement and similitude of effects, I think it may be inferred, that they are mixt with, and generally do accompany each other ; and that each produces its own effect at the time of their joint operation. The effects of electricity, similar to those of fire, being produced by the fire mixt with it ; and the effects of fire, resembling those of electricity, being produced by the clectricity mixt with that : the compound taking its name from the predominant principle.” Is it not more probable that
one fluid, operating in different modes and circumstances, produces those different effects :
II. Observations on light, and the waste of m:atter in the sun and frt stars, occasioned by the Aconstant efflux of light from them ; with a conjecture, hrafiosed by way of query, and suggestàng a mean, by which their several systems might be fireserved from the disorder and final ruin, £o which they seem liable by that waste of matter, and by the law of gravitation. By James Bowdoin, Esquire, President of the American Academy of Arts and Sciences. Dr. Franklin had made some Aobjections to the Newtonian doctrine of light on the ground, that there most consequently be a moinentum or force in the particles
of light, and a waste in the matter of the sun, which do not accord with experience and observation. Mr. Bowdoin endeavours to remove these objections. Accordingly the “Observations on Light” in the former part are calculated to show, that the inference relative to the motion or momentum of light is not just, and of course the objection, raised on it, unfounded. In the other part, after some good observations on the waste of matter in the sun by emission of light, the hypothesis is introduced, which is announced with so much modesty and caution in the title. The author,apparently well apprized of the difficulty of supporting it with evidence, merely proposes it as a query, or .." of consideration. That wonderful phenomenon, the ring of Saturn, which appears to the planet like a vast, surrounding, luminous arch, suggested the idea of conjecturing that a hollow sphere or orb might encompass the several systems, which compose the visible heavens. This surrounding orb is supposed to be fitted by its structure, and the properties of gravity, repulsion of light, &c. with which it is furnished to stop the rays of light, reflect them to the source, whence they emanated, and thus prevent loss or waste of any matter within it, and preserve the magnitude of the sun and stars; and also to serve as a counterbalance to the mutual gravities of the systems and bodies, inclosed by it, thus contributing to the preservation of their relative distances, and the prolongation of their regular motions. The following remark shows, that the author was not insensible to the weight of objections. “To this hypothesis objections may be made, and such as might prove it to be, like many an one which has preceded it, a mere philosophical reverie.”
III. Observations tending to frowe, by finanomena and scrifiture, the eristence of an orb, which surrounds the whole visible, material system ; and which may be necessary to fireserve it from the ruin, to which, without such a counterbalance, it seems liable by that universal firinciple in matter, gravitation. By James Bowdoin, Esq. President of the American Academy of Arts and Sciences. In this Memoir is adduced the evidence, on which the author depends to support his hypothesis of an all-surrounding orb. “The evidence is—phoenomena and scripture. “The phoenomena are—the luminous girdle in the blue expanse, called the Milky Way ; other luminous appearances in it; and the expanse itself.” ... With respect to the Milky Way, objection is made to the opinion, that its appearance is occasioned by the blended light of stars; and it is observed, “the phoenomenon strikes us, as it may be supposed, such a luminous girdle would strike, if its light were reflected from the concave surface of a far distant orb; to which, on the hypothesis assumed, it had been proPelled from the numerous systems which the orb enfolds.” o o Quotations are given from Ferguson and Smith, containing some observations on the milky way, and descriptions of some whitish spots or luminous appearances in the heavens. And it is observed, “From these phoenomena it seems not improbable, that the Milky Way, and those lucid spots, are parts of a concave body or orb, of the same nature with some of the other heavenly bodies; and whose
light transmitted to us, exhibits those phoenomena, according to the laws and circumstances, which regulate it.” Sir Isaac Newton's explanation of “ the blue concave expanse, which surrounds, and appears to limit visible nature,” is considered as unsatisfactory. The opinion rehatively to this phenomenon, entertained by this author, and his ground for supporting it, may be seen in the following extract. “Nature is simple and uniform: in its operations. From the same cause follow like effects; and these indicate the same cause. Bodies of every kind, through the medium of light, produce their respective phoenomena, and these demonstrate the reality of those bodies. “From these principles we infer the reality of those terrestrial bo. dies, which, by reason of their situation and distance, can only be the objects of sight: and from the same principles we also infer the reality of the heavenly bodies, the planets, and fixed stars. If this, last inference be just, is it not equally just to infer, from the same principles, the reality of the blue circumambient expanse : that is, that it is a real concave body, encompassing all visible nature ?” After the statement of such evidence in favour of an orb surrounding the visible universe, as seems to him to be deducible from natural phoenomena, farther light is sought in the sacred scriptures. His own words express his sentiments on the propriety of recurring to this source of information. “In regard to the subject in hand, there seems to be a happy coincidence between phoenomena and scripture ; and therefore in further evidence of such an orb, and in evidence of several other orbs similar, and concentrick to it,