able is the world, in this point of view, with all its buffetings, repulfes, and rude affaults, to disturb the temper of his foul, or elfentially to wound his tranquility. I fay effentially; for I am far from thinking, that even the good man, the man who has chofen God for his portion, and who makes the law of God his meditation and delight, can, in this world of forrows, enjoy a tranquility fo unalterable as never to be ruffled by misfortune, interrupted by anxiety, or disturbed by care. Alas! alas! Such a state is unattainable by man upon earth. Those anxieties, however, are but as paffing clouds. They difcharge their contents on the furface of the foul, but it is only on its furface. Its substance they reached not. This is impervious and impaffible. It is without only that the clamour is heard; for within reigns a profound ftillness, a folemn filence, a perpetual calm; that applaufe of confcience, that fimplicity of heart, that equanimity of temper, that lively confidence, that univerfal peace, which anticipates the felicity of heaven, and begins the life of angels here below. The difquietudes infeparable from nature he feels changing themselves into a mild and gentle refignation; a ray of celeftial light darting inwards upon his mind, and reftoring its ferenity and the peace of God which paffeth understanding penetrating his heart, and fweetening all its bitternels! O happy condition of virtue! Why art thou not more studied, more coveted and more known of men? And wherefore do we paint thee in colours fo gloomy and difagreeable, thou, who only canft leffen all the miferies of this exile, and foften all its pains."

The subsequent addrefs is ftriking and pathetic:

"Frequently then, in thought, anticipate the moment of your departure from the prefent introductory state of things, and live and act precisely in fuch a manner as you will then wish to have acted and lived. Anticipate that serious and folemn period when, with respect to you, riches and every other tranfient distinction, all but your integrity, fhall be vanished and gone. Suppose it actually arrived. Suppofe yourfelves now upon a death-bed. It is an awful fuppofition; but how foon may it be realized! I ask you-and I beg that the question may be weighed, and much reflected on in your most fecret retirement.-What shall support you in this labouring hour of nature, this moment of difficulty and doubt, when remedies unattended with fuccefs, a defpairing physician, a family bathed in tears, when every thing, in fine, announces your approaching diffolution, if the retrospect of life, and the reflections which you will then be obliged to make on your paft conduct, and on the ufe and improvement of your profperity, prefent you only with a barren fcene; if they difguft you with a dreary safe, a blank, a void, a perfect vacancy; if they offer to recollection no poor man relieved, no mourner comforted, no ftranger lodged, no ignorant inftructed, no naked cloathed, no gratulations of an approving heart, but, in their ftead, reproaches loud and deep? O mifery! Mifery! Sweet is even the bittereft cup of affliction, compared with the gall of iniquity and remorfe!"

In the fourth Sermon, On the Nature and Extent of Chriftian Charity, our author hath expreffively delineated the character of a flanderer.

For the further entertainment of our readers, we will present them with the concluding paragraph of this volume of Sermons. It contains the Doctor's affectionate addrefs to his audience.

"I close this difcourfe (on the conceffions of the enemies of the Gospel a proof of its truth) by befeeching you not to rest in a bare profeffion or belief of the Gofpel, but to evidence that belief by your actions, to adorn that profeffion by a fuitable practice. Little will it avail you to have the fulleft reliance upon the merits, interceffion, and death of Chrift, if your total want of his fpirit and temper undeniably demonftrate that you are none of his. There is an infidelity of the heart and affections as obstructive of falvation as the infidelity of the understanding. A man who rerefufes to believe, notwithstanding the manifold proofs of Chriftianity, is an object not more of horror than of pity: but a Chriftian who believes, yet lives as if he did not believe, is a character for whofe extravagance it is difficult to find a name. The first refembles a madinan, who throws himself headlong into the flood; the second, a fool who ftands immoveable on the fhore, calmly fuffers himself to be drawn in by the waves, and looks for fafety in the very jaws of deftruction. See then that ye walk circumspectly, not as fools, but as wife. The foul of the fluggard, fays Solomon, defireth and hath nothing; but the foul of the diligent shall be made fat. Thus precifely fares it with the fpiritually flothful and the fpiritually induftrious. In religion there is no fuch state as that of cold, inactive neutrality; nor knows it a medium betwixt punishment and reward. We must be wholly the Creator's or wholly belong to the world. We must be covered with fhame and infamy, as the fearful, indolent, and unbelieving or be crowned with glory as the active, magnanimous, and heroic. We must be pillars in the temple of God, have the morning ftar, be cloathed in white raiment, have power over the nations, and rule them with a rod of iron, and fit down with Jefus on his throne, with thofe who have overcome and been faithful unto death: or, with the flothful and unprofitable fervant be caft into outer darkness, where is weeping, wailing, and gnashing of teeth. Begin then your work without lofs of time, now, that you are in this affembly, now, that you are under the immediate eye of God, and under the authority of his divine word. Begin, and you will find at length peace of conscience, and that reft to your fouls, which is a foretafte only of that compleater reft to be enjoyed through eternity in the paradife of God."

On the whole, we look upon our author in the light of a flimfy orator, and pronounce that this performance (though it contains fome excellencies) will by no means gain a place among the works of celebrated divines, which are worthy, Linenda cedro; et lævi fervanda cupresso.

Political

Political, Mifcellaneous, and Philofophical Pieces, arranged under the following Heads, and diflinguished by initial Letters in each Leaf; [G. P.] General Politics; [A. B. T.] American Politics before the Troubles; [A. D. T.] American Politics during the Troubles; [P. P.JProvincial or Colony Politics; and [M. P.] Mifcellaneous and Philofophical Pieces; written by Benjamin Franklin, L. L. D. and F. R. S. Member of the Royal Academy of Sciences at Paris, of the Royal Society at Gottingen, and of the Batavian Society in Holland; Prefident of the Philofophical Society at Philadelphia; late Agent in England for feveral of the American Colonies; and at prefent chofen in America as Deputy to the General Congress for the State of Penfylvania; Prefident of the Convention of the faid State, and Minifter Plenipotentiary at the Court of Paris for the United States of America: now first collected with explanatory Plates, Notes, and an Index to the Whole. 10s. 6d. 8vo. Johnson. [Concluded from page 181.]

There is no phoenomenon, perhaps, in the natural world, about which the opinions of philofophers are more divided, than that of the Aurora Borealis. Till of late, indeed, no rational or philofophical account was attempted to be given of this very ftrange and fingular appearance. Popular conjectures were almoft all that took place on the fubject; and thefe, as ufual, were in the higheft degree abfurd and ridiculous. Dr. Franklin is one of the first that has endeavoured to explain this phænomenon upon the found principles of reafon and philofophy; and with his fentiments on this topic we fhall conclude our review of this very curious and enter taining publication.

"Suppofitions and Conjectures towards forming an Hypothefis, for the explanation of the Aurora Borealis.

"1. Air heated by any means, becomes rarified, and specifically lighter than other air in the fame fituation not heated.

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2. Air being made thus lighter rifes, and the neighbouring cooler heavier air takes its place.

66. 3. If in the middle of a room you heat the air by a stove, or pot of burning coals near the floor, the heated air will rife to the ceiling, fpread over the cooler air till it comes to the cold walls; there, being condensed and made heavier, it defcends to fupply the place of that cool air which had moved towards the ftove or fire, in order to fupply the place of the heated air which had afcended from the space around the stove or fire.

VOL. XI.

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"4. Thus

66 Thus there will be a continual circulation of air in the 4. room; which may be rendered vifible by making a little smoke, for that smoke will rife and circulate with the air.

5. A fimilar operation is performed by nature on the air of this globe. globe. Our atmosphere is of a certain height, perhaps at a medium ] miles above that height it is fo rare as to be almost a vacuum. The air heated between the tropics is continually rifing; its place is fupplied by northerly and foutherly winds, which come from the cooler regions.

6. The light heated air floating above the cooler and denfer, muft fpread northward and fouthward; and defeend near the two poles, to fupply the place of the cool air, which had moved towards the equator.

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7. Thus a circulation of air is kept up in our atmosphere, as in the room above mentioned.

8. That heavier and lighter air may move in currents of different and even oppofite direction, appears fometimes by the clouds that happen to be in thofe currents, as plainly as by the fmoke in the experiment above mentioned. Alfo in opening a door between two chambers, one of which has been warmed, by holding a candle near the top, near the bottom, and near the middle, you will find a strong current of warm air paffing out of the warmed room above, and another of cool air entering below; while in the middle there is little or no motion.

9. The great quantity of vapour rising between the tropics forms clouds, which contain much electricity.

"Some of them fall in rain, before they come to the polar regions.

66 10. If the rain be received in an isolated veffel, the vessel will be electrified; for every drop brings down fome electricity with it. 11. The fame is done by fnow or hail.

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12. The electricity fo defcending, in temperate climates, is received and imbibed by the earth.

13. If the clouds are not fufficiently difcharged by this gradual operation, they fometimes difcharge themfelves fuddenly by ftriking into the earth, where the earth is fit to receive their electricity.

14. The earth in temperate and warm climates is generally fit to receive it, being a good conductor.

15. A certain quantity of heat will make fome bodies good conductors, that will not otherwise conduct.

16. Thus wax rendered fluid, and glass foftened by heat, will both of them conduct.

17. And water, though naturally a good conductor, will not conduct well, when frozen into ice by a common degree of cold;. not at all, where the cold is extreme.

"18. Snow falling upon frozen ground has been found to retains its electricity; and to communicate it to an isolated body, when after falling, it has been driven about by the wind.

64 19. The humidity contained in all the equatorial clouds that

reach

reach the polar regions, muft there be condenfed and fall in fnow.

.. 20. The great cake of ice that eternally covers those regions may be too hard frozen to permit the electricity, descending with that fnow, to enter the earth.

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21. It may therefore be accumulated upon that ice.

22.

The atmosphere being heavier in the polar regions, than in the equatorial, will there be lower; as well from that cause, as from the fmaller effect of the centrifugal force: confequently the diftance of the vacuum above the atmosphere will be lefs at the poles than elsewhere; and probably much less than the distance (upon the furface of the globe) extending from the pole to thofe latitudes in which the earth is fo thawed as to receive and imbibe electricity; (the froft continuing to lat. 80, which is ten degrees, or 600 miles from the pole; while the height of the atmosphere there of fuch denfity as to obstruct the motion of the electric fluid, can scarce be esteemed above { ] miles). 23. The vacuum above is a good conductor.

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24. May not then the great quantity of electricity, brought into the polar regions by the clouds, which are condenfed there, and fall in fnow, which electricity would enter the earth, but cannot penetrate the ice; may it not, I fay (as a bottle overcharged) break through that low atmosphere, and run along in the vacuum over the air towards the equator; diverging as the degrees of longitude enlarge; ftrongly vifible where denfeft, and becoming lefs visible as it more diverges; till it finds a paffage to the earth in more temperate climates, er is mingled with their upper air?

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25. If fuch an operation of nature were really performed, would it not give all the appearances of an Aurora Borealis ?

"26, And would not the auroras become more frequent after the approach of winter: not only because more vifible in longer nights; but also because in fummer the long prefence of the fun foften the furface of the great ice cake, and render it a conductor, by which the accumulation of electricity in the polar regions will be prevented?

may

"27. The atmosphere of the polar regions being made more denfe by the extreme cold, and all the moisture in that air being frozen; may not any great light arifing therein, and paffing through it, render its denfity in fome degree vifible during the night time, to those who live in the rarer air of more fouthern latitudes; and would it not in that cafe, although in itself a complete and full circle, extending perhaps ten degrees from the pole, appear to fpectators fo placed (who could fee only a part of it) in the form of a fegment; its chord refting on the horizon, and its arch elevated more or less above it as seen from latitudes more or less distant; darkish in colour, but yet fufficiently transpareut to permit fome ftars to be seen through it.

"28. The rays of electric matter iffuing out of a body, diverge by mutually repelling each other, unless there be fome conducting body near, to receive them and if that conducting body be at

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a greater