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HOW came still evening on, and twilight gray
As when the moon, refulgent lamp of night! Oer heav'n's clear azure spreads her sacred light, When not a breath disturbs the deep serene, And not a cloud o'ercasts the solemn scene; Around her throne the vivid planets roll, And stars unnumber'd gild the glowing pole, O'er the dark trees a yellower verdure shed, And tip with silver ev'ry monntain's head; Then shine the vales, the rocks in prospec. rise, A flood of glory bursts from all the skies : The conscious swains, rejoicing in the sight, Eye the blue vault, and bless the useful light.
By Dr. Johnson. (Poft Lexicon Anglicanum auctum et emenda
DORINDA's sparkling wit and eyes,
United, cast too fierce a light, Which blazes high, but quickly dies,
Pains not the heart, but hurts the sight.
Love is a calmer, gentler joy,
Sinooth are his looks, and soft his pace ;
pires, Where Comus revels, and where wine inspires, Delight no more : I seek iny lonely bed, And call on feep to soothe my languid head. But fleep from these fad lids flics far away ; Imourn all righi, and dread the coming day. Exhauled, tird, 1 throw my eyes around, To find some vacant fpot on clasick ground; And soon, vaini lope! I forn a grand design; Languor succeeds, and all my pow'r decline.
e Sec Scaliger's epigrain on the same fubiect, communicated, without doubt, by Dr. Jo! non, Gent. Mag. 1743, p. 8.
THE BOSTON REVIEW,
For APRIL, 1806.
Librum tuum legi & quam diligentissime potui annotavi, quæ commutanda, quæ eximenda, ar
bitrarer. Nam ego dicere verum assuevi. Neque ulli patientius reprehenduntur quam qur maxime laudari merentur. Pliny.
hypothesis, maintained by Sir Isaac [Concluded.)
Newton and others, light consists
of particles of matter, extremely Niemoirs of the American Academy minute, which being projected or
of Arts and Sciences. Vol. 1. thrown off from luminous bodies 1805. 4to. pp. 564.
in every direction by a repulsive Part II. PHYSICAL Papers.
force, and reflected by opaque bo
dies, produce the sensation of vi1. Observations upon an hypoth- sion by impulse on the eye. esis for solving the phenamena of The hypothesis, on which the light, with incidental observations, author of this Memoir remarks, is tending to shew the heterogeneous- contained in some queries, propos, ness of light, and of the electricked by Dr Franklin, and is in subfluid, by their intermixture, or stance the same as the former of union, with each other. By James the two preceding ; to which the Bowdoin, Esquire, President of the observations may be considered as American Academy of Arts and objections, or arguments in favor
of the other The celebrated Dr. Franklin ob- In one part of the reasoning in served, that he was much in the form of queries relative to the prodark about light. And it must be duction of light in various instances acknowledged, that, notwithstand by motion, on supposition that the ing the great progress we have hypothesis of vibration is true, made in opticks, many difficulties more seems to be assumed than is still remain relative to the nature of granted in the hypothesis. It does light, or the manner in which vis- not appear to be inferable from Dr. ion is produced. It is well known, Franklin's statement, nor from any that modern philosopliers have other, that we recollect to have proposed two hypotheses far the seen, that every kind and degree of purpose of explaining this point. motion in the elastick fluid is supIn one, adopted by Huygens, Eu posed or admitted to be productive ler, and some others, an extremely of the sensation of vision; nor subtile, elastick fluid is supposed does this seem to be a necessary to penetrate all bodies, and to fill all consequence. In the theory of space; and vibrations being excited sound, though the vibratory agenin it by the action of luminous cy of the air is clearly ascertained, bodies, are propagated to the eye, yet it is not supposed that every and produce in that organ the sen- kind and degree of motion in the sation of vision in the same man- air produces the sensation of ner, as pulsations of air pro duce in sound. the organ of hearing the se nsation The author's ideas respecting of sound. According to the other the heterogeneousness of light and of the electrick fluid may be well of light, and a waste in the matter learned from the foilowing extract, of the sun, which do not accord it being noted, that he uses fire in with experience and observation. it as synomimous with light. Mr. Bowdoin endeavours to re
“ Electricity and fire differ in move these objections. Accordmany respects, and in some they ingly the “ Observations on Light” agree ; as hath been shewn in in the former part are calculated Dr. Franklin's letters on elec- to show, that the inference relative tricity. So far as they agree in to the motion or momentum of their effects, their nature may be light is not just, and of course the presumed to be alike : or rather, objcction, raised on it, unfounded. from that agreement and simii. In the other part, after some good tude of effects, I think it may be observations on the waste of matinferred, that they are mixt with, ter in the sun by emission of light, and generally do accompany each the hypothesis is introduced, which other ; and that each produces its is announced with so much modown effect at the time of their esty and caution in the title. The jcint operation. The effects of author,apparently well apprized of electricity, similar to those of fire, the difficulty of supporting it with being produced by the fire mixt evidence, merely proposes it as a with it ; and the effects of fire, query, or subject of consideration. resembling those of electricity, be That wonderful phenomenon, the ing produced by the clectricity ring of Saturn, which appears to mixt with that : the compound the planet like a vast, surrounding, taking its name from the predom- luminous arch, suggested the idea inant principle."
of conjecturing that a hollow Is it not more probable that sphere or orb might encompass one fluid, operating in different the several systems, which commodes and circumstances, produ- pose the visible heavens. This ces those different effects ?
surrounding orb is supposed to be
fitted by its structure, and the II. Observations on light, and properties of gravity, repulsion of the waste of matter in the sun light, &c. with which it is furnishand fixt stars, occasioned by the ed to stop the rays of light, reflect constant efflur of light from them to the source, whence they thein ;, with a conjecture, propos. emanated, and thus prevent loss or #ed by way of query, and suggest waste of any matter within it, and
ng a mean, by which their sever preserve the magnitude of the sun al systems might be preserved and stars; and also to serve as a from the disorder and final ruin, counterbalance to the mutual grayto which they seem liable by that ities of the systems and bodies, invaste of matter, and by the law closed by it, thus contributing to of gravitation. By James Bow the preservation of their relative doin, Esquire, Presid nt of the distances, and the prolongation of American Academy of Arts and their regular motions. Sciences.
The following remark shows, Dr. Franklin had made some that the author was not insensible objections to the Newtonian doc- to the weight of objections. “To trine of light on the ground, that this hypothesis objections may be there most consequently be a no- made, and such as might prove it mentum or force in the particles to be, like many an one which has
preceded it, a mere philosophical light transmitted to us, exhibits reverie."
those phænomena, according to
the laws and circumstances, which III. Observations tending to regulate it.” prove, by phænomena and scripture, Sir Isaac Newton's explanation the existence of an orb, which sur- of “ the blue concave expanse, rounds the whole visible, material which surrounds, and appears to system ; and which may be necessa- Jimit visible nature,” is considered Ty 10 preserve it from the ruin, to as unsatisfactory. The opinion tohich, without such a counterbal- relatively to this phenomenon, enence, it seems liable by that universal tertained by this author, and his principle in matter, graviation. By ground for supporting it, may be James Bowdoin, Esq. President seen in the following extract. of the American Academy of Arts « Nature is simple and uniform and Sciences.
in its operations. From the same In this Memoir is adduced the cause follow hike effects; and these evidence, on which the author de indicate the same cause. Bodies pends to support his hypothesis of of every kind, through the median all-surrounding orb.
um of light, produce their respect“The evidence is phenomena ive phænomena, and these demonand scripture.
strate the reality of those bodies. « The phenomena are the lu- «From these principles we infer minous girdle in the blue expanse, the reality of those terrestrial bocalled the Milky Way ; other lu- dies, which, by reason of their situminous appearances in it ; and the ation and distance, can only be the expanse itself.”
objects of sight: and from the With respect to the Milky Way, same principles we also infer the objection is made to the opinion, reality of the heavenly bodies, the that its appearance is occasioned planets, and fixed stars. If this by the blended light of stars ; and last inference be just, is it not it is observed, to the phenomenon equally just to infer, from the same strikes us, as it may be supposed, principles, the reality of the blue such a luminous girdle would circumambient expanse ; that is, strike, . if its light were reflected that it is a real concave body, enfrom the concave surface of a far compassing all visible nature ?" distant orb; to which, on the hypo. After the statement of such eve thesis assumed, it had been pro- idence in favour of an orb surroundpelled from the numerous systems ing the visible universe, as seems which the orb enfolds."
to him to be deducible from naturQuotations are given from Fer- al phænomena, farther light is guson and Smith, containing some sought in the sacred scriptures. observations on the milkyway, His own words express his sentiand descriptions of some whitish ments on the propriety of recur: spots or luminous appearances in ring to this source of information, the heavens. And it is observed, ." In regard to the subject in “ From these phenomena it seems hand, there seems to be a happy Aot improbable, that the Milky coincidence between phænomena Way, and those 'lucid spots, are and scripture ; and therefore in parts of a concave body or orb, of further evidence of such an orb, · the same nature 'with some of the and in evidencë' of several other other heavenly bodies; and whose orbs similar, and concentrick to it,