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 anixt 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? Observations on light, and the waste matter in the sun and fixt stars, occasioned by the Constant efflux of light from them; with a conjecture, propos ed by way of query, and suggesting a mean, by which their several systems might be preserved from the disorder and final ruin, to 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 objections to the Newtonian doctrine of light on the ground, that there most consequently be a momentum 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 subject 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 light transmitted to us, exhibits reverie." those phenomena, according to the laws and circumstances, which regulate it." III. Observations tending to frove, by phenomena and scripture, the existence of an orb, which surrounds the whole visible, material system; and which may be necessary to preserve it from the ruin, to which, without such a counterbalance, it seems liable by that universal principle 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 phenomena and scripture. "The phænomena are the lu minous 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 phenomenon 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." bo 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 phænomena 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 Sir Isaac Newton's explanation of "the blue concave expanse, which surrounds, and appears to limit visible nature," is considered as unsatisfactory. The opinion relatively 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 medi um of light, produce their respective phenomena, and these demonstrate the reality of those bodies. "From these principles we infer the reality of those terrestrial bodies, which, by reason of their situ ation 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 natur al phenomena, farther light is sought in the sacred scriptures. His own words express his sentiments on the propriety of recur ring to this source of information. "In regard to the subject in hand, there seems to be a happy coincidence between phenomena and scripture; and therefore in further evidence of such an orb, and in evidence of several other orbs similar, and concentrick to it, we may recur to scripture : sev- terbalance. But if we cannot diseral passages of which appear ap- cover sufficient reason to admit plicable to that purpose. this supposition as a constituent “ It seldom happens that natural part of the fabrick of science, we philosophy is made to borrow as- think it merits a respectable place sistance from thence : but though in her collection of curious hyscripture may not be intended to potheses, formed by eminent instruct us in the philosophy of men. material nature, it may neverthe less give, and be intended to give, IV. An account of a very unsome hints of its constitution, or common darkness in the states of general system." New-England, May 19, 1780. By The passage, first adduced as Samuel Williams, A. M. Hollis Proevidence of the author's hypothe- fessor of Mathematicks and Philososis, is, he observes, “ a remarkable phy in the University at Cambridge. one, and may serve in some mea- The extraordinary darkness of sure to elucidate the rest.” “ It the 19th of May, 1780, cannot be is God that builded his stories in the easily forgotten by those who obheavens."* served it. We are happy to see From the preceding extracts, an account of that phænomenon some idea may be formed of the preserved, which we think will be hypothesis of an all-surrounding read with no small interest by the orb, the ground on which it rests, lovers of natural knowledge. The and the author's view of certain facts, which Dr. Williams had phænomena. This hypothesis is been able to collect, are related proposed for consideration in a with clearness and the general manner well calculated to engage principles of the explanation apthe attention, and secure the can- pear to us to be satisfactory. dour of the reader. We have According to this statement, the been entertained in the perusal, unusual darkness began between though our ideas do not coincide 10 and 11 o'clock in the morning, with the author's in all his reason and continued till midnight ;ings and conclusions. By enlarg- from the accounts received the exing the powers of telescopes and act boundaries of it could not be extending our views into the celes- determined, but it seemed to have tial regions, we find new evidence extended through the New-Engin favour of the opinion, that the land states.. There was some va. lucid appearance of the milky way rietysåve the appearances, the deand some other parts of the etheri- gree of darkness, and probably in al expanse, arises from the blend.. the duration at different places ;ed light of stars, and new reason « in most parts of the country peoto doubt the reality of a solid sur- ple were unable to read common rounding orb. Observation and print; determine the time of day theory render it probable, that suf- by their clocks or watches ; dine, ficient provision is made for pre- or manage their domestick busiserving the harmony of the mo- ness without the light of candles ;" tions in the various systems, which the colour of the clouds appeared. compose the universe, without the to be a mixture of faint red, yellow supposed external, enclosing coun- and brown, and most other objects appeared to be tinged with yellow; Amos ix. 6. thunder was heard in the morn ing, and rain fell in small showers, a much larger quantity of vapour which appeared to be thick, dark, arose from those large and pimerand sooty, and on the surface of it, ous fires which extended all awhen received in vessels, as well round our frontiers. As the weathas on that of rivers, &c. a light er had been clear, the air heavy, scum was observed, which on ex- and the winds small and variable amination was found to be the for several days ; the vapours inblack ashes of burnt leaves ; in stead of dispersing, must have some places the vapours seem- been rising and constantly collected to be ascending; “ in most de- ing in the air, until the atmosscending ; and in all very near to phere became bighly charged with the surface of the earth ;" « the an uncommon quantity of them, appearance and effects were such floating near the surface of the as tended to make the prospect ex. earth.” tremely dull and gloomy; candles To this account is annexed some were lighted up in the houses ; information, principally taken from the birds having sung their even- the English Philosophical Transing songs, disappeared and became actions, respecting instances of exsilent ; the fowls retired to roost; traordinary darkness, which in the cocks were crowing all around former times had been observed in as at break of day ; objects could America. not be distinguished but at a very little distance, and everything V. An account of the effects of bore the appearance and gloom of lightning on two houses in the city night.” of Philadelphia. By the Hon. ArA general view of the cause of thur Lee, Esq. F. A. A. this wonderful darkness is exhibit- The lightning, which produced ed in the following extract. the effects here described, happen “ It is well known that in this ed in the summer of 1781. One part of America, it is customary to of the houses was unprotected by make large fires in the woods, for a conductor; and the copper print the purpose of clearing the lands of the conductor of the other apin the new settlements. This was peared, on examination, to have the case this spring, in a much been melted, at some preceding greater degree than is common. time, into a form, resembling that In the county of York, in the west- of a button. The lower end of this ern parts of the state of New conductor was about two feet beHampshire, in the western parts low the surface of the ground. In of this state, and in Vermont, un- each case the Auid appeared to commonly large and extensive have passed through a considerafires had been kept up. The peo- ble extent of the building by one ple in the new towns had been or more bell-wires, which, though employed in clearing up their melted in some parts, answered lands in this way for two or three the purpose of conducting the weeks before ; and some large and charge ; the falling however of the extensive fires had raged in the fused metal on the floor occasionwoods for several days before they ed the burning of holes in it. The could be extinguished. In addi- course and effects of the lightning tion therefore, to what arises from in one of the houses is particularevaporation, and those exhalations ly marked by a figure. which are constant and natural, In some remarks, suggested by Vol. III. No. 4. 2B the facts he had related, Mr. Lee justly observes, that bell-wires in a house "ought always to be disposed with a view to the possibility of their becoming conductors." And," that the points of conductors should be examined from time to time." VI. An account of the effects of lightning on a large rock in Gloucester. By the Reverend Eli Forbes. The time, when lightning produced the effects here described, was the 18th of March, 1782. The content of the rock above the ground, on which the discharge was made near the top, is almost ten feet. The lighting, having broken off about 20 pounds of the rock, and beside cracked it in several directions to a small extent, was divided into three parts, which passed off in different directions, each producing effects, that were very striking. Dr. Forbes appears to have examined these effects with close attention, and to have described them with great accuracy. He has illustrated them by a figure. They were indeed extraordinary. It is very much to be wished, that whenever lightning strikes an object on the earth, some person, who lives near it, would examine the visible traces, and communicate all the facts, which he can ascertain, to the Academy or some other society, that, if valuable, they may become publick, and may be applied, as far as ther nature will, admit, to the purpose of improving our knowledge on this highly important subject. VII. An account of a very curious appearance of the electrical fluid, produced by raising an electrical kite in the time of a thunder shower. By Loammi Baldwing Esq. F. A. A. In this experiment, performed in the summer of 1771, an electrical kite was elevated to the height of some tall trees, or perhaps somewhat above them, at a time, when the upper edge of a highly charged cloud, rising from the north-west, had reached the altitude of 55° or 60°. Col. Baldwin was soon surrounded with the appearance of a fiery atmosphere, or bright flame of fire, with some faint flashes, visible to himself and other persons at a small distance. This electrical phenomenon continued to increase and extend itself till, the cloud having nearly obscured the heavens about the zenith, the kite was drawn down. The experimenter however was subjected to no inconvenience but surprise, and a degree of debility, which, he thinks, that surprise might possibly have occasioned. VIII. Observations and conjectures on the earthquakes of NewEngland. By Professor Williams, F. A. A. The design in writing this treatise and the plan of it are exhibited in the following extract,which is the first paragraph of it. "In looking over some of the histories of New-England, I observed, that the religious turn of mind,which distinguished the first planters of New-England, had led them to take notice of all the earthquakes which happened in the country after their arrival. Several of them seemed to be pretty well described; and in some of their phenomena there seemed to be an agreement. As several of these accounts were contained in writings but little known, I thought it might be of some service to philosophy, if a |