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the power of the Junto to oblige him, or encourage him as he deferves?

• Do you know, of any deferving young beginner, lately fet up, whom it lies in the power of the Junto any way to encourage?

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• Have you lately obferved any defect in the laws of your country, of which it would be proper to move the legislature for an amendment? Or do you know of any beneficial law that is wanting?

• In what manner can the Junto, or any of them, assist you in any of your honourable designs?

Is there any difficulty in matters of opinion, of juftice and injuftice, which you would gladly have difcuffed at this time?'

The fifth and last division of this valuable collection contains the miscellaneous, principally philofophical, pieces of Dr. Franklin. The firft, which is a Scheme for a new Alphabet: and reformed Mode of Spelling,' will not admit of abridgment. The fecond is a letter to a friend, witten in 1748, on perufing Mr. Baxter's Treatife on the Soul; in which Dr. Franklin opposes the common doctrine of the vis inertia of matter, as inconfiftent with the phenomena of bodies in motion. An idea of the Author's reasoning on this fubject may be collected from the fallowing cafe.

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It is acknowledged, that if a body, A, moving with the celerity, and the force 1 f, impinge against another equal body, B, at reft; the two bodies will move on together after the ftroke, each with half the celerity and force of the first body; or each will move with c, and fi but the celerity and force of both bodies added together is I c, and I f; that is, precifely the celerity and force of the body A, before the ftroke. In this cafe, there is no abatement of velocity or force:-Where then is the vis inertia? What does it, or how does it difcover itfelf?'

The next paper contains Experiments, Obfervations, and Facts, tending to fupport the Opinion of the Utility of long painted Rods, for fecuring Buildings from Damage by Strokes of Lightning-and was read at the Committee of the Royal Society, appointed to confider the erecting conductors, to fecure the magazines at Purfleet, in Auguft 1772. The experiments, though valuable on account of that luminous fimplicity which diftinguishes all the productions of this great man-in politics, as well as in philosophy, cannot eafily be described without the affiftance of the plate that accompanies them. An observation, however, of a more popular kind, and more generally intelligible, may be here inferted with propriety.

In oppofition to the advantages expected to be derived from the use of high pointed rods, it may be alleged, that the means are

not

.

not adequate to the propofed end:-that though, in our: fmall experiments, a fine pointed needle will filently, and almoft: inftantly, discharge the electric matter from a charged prime conductor, or even an electrical battery, at the diftance of a few inches; no fuch advantages are to be hoped for, in any, confiderable degree, from a pointed rod opposed to a charged cloud, many acres in extent, at the diftance of half a mile, or a mile, or more. But that high pointed rods may rob a cloud of very great quantities of electric matter; and thereby poffibly difarm it of the power of doing mifchief, is rendered evident by the following fact;

The Author's house at Philadelphia, was furnished with at rod extending nine feet above the top of the chimney. To this rod was connected a wire of the thickness of a goofe quill, which defcended through the well of the stair-cafe; where an interruption was made, fo that the ends of the wire, to each of, which a little bell was fixed, were diftant from each other about fix inches; an infulated brass ball hanging between the two bells. The Author was one night waked by loud cracks, proceeding from his apparatus in the ftair cafe. He perceived, that: the brais ball, inftead of vibrating as ufual between the bells, was repelled and kept at a diftance from both; while the fire fometimes paffed in very large quick cracks directly from bell to bell; and fometimes in a continued denfe white stream, feemingly as large as his finger; by means of which the whole ftair-cafe was enlightened, as with fun-fhine,' fo that he could fee to pick up a pin.-From the apparent quantity of electric matter of which the cloud was thus evidently robbed, by means of the pointed rod (and of which a blunt conductor would not have deprived it), the Author juftly conceives, that a number * of fuch conductors must confiderably leffen the quantity of electric fluid contained in any approaching cloud, before it comes fo near as to deliver its contents in a general ftroke.'

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The laft piece in this collection, is a paper under the modest title of Suppofitions and Conjectures towards, forming an Hypothefis, for the Explanation of the Aurora Borealis.' Some idea of the Author's attempt to form an hypothefis on this fubject, may be collected from the following short sketch of it:

The air, "heated between the tropics, and containing a great quantity of vapour, replete with electric matter, is rendered light, and accordingly rifes into the upper parts of the atmosphere; and after spreading northwards and fouthwards, onthe different fides of the equator, it finally defcends near the two poles: from whence an oppofite current of cool and denfe air is, at the fame time, put in motion towards the equator, to

* Twelve were propofed on and near the magazines at Purfeet.

Supply

fupply its place. This circulation of warm and cool, i. e. of light and heavy, air, is eafily rendered vifible, in a room where there is a fire, by means of a little smoke,

In the paffage of the electrified vapour to the northward, for inftance, in the form of clouds, great part of it is precipitated, before it arrives at the polar regions, in rain, fnow, or hail. That thefe contain electric matter, is rendered evident by receiving them in infulated veffels; to which they communicate their electricity.

In the temperate regions, this electricity is readily received and imbibed by the earth; which, in those climates, is a good conductor; and which will receive it either filently, conveyed to it by the rain, &c. or fuddenly, in the explosions, attending thunder ftorms.

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In the cold polar regions, however, the cafe will be different. That part of the electrified vapour which reaches them, and defcends with the fnow, does not fall on a conducting earth; but on a vitriform cake of ice, with which the earth is there eter-. nally covered; and which (particularly when the cold is extreme +) will not conduct electricity. The electric matter therefore not being able to penetrate through this non-conducting ftratum, will be accumulated on the furface of it, as on a plate of glafs.

This plate of ice thus becoming overcharged, the electric matter will, at different times, burst from it, as happens when a Leyden vial has been overcharged; and will break through the fuperincumbent atmosphere (lower here than at the equator) till it arrives at the vacuum, or highly rarefied air, above, which is a good conductor; where it will run along towards the equator, diverging as the degrees of longitude enlarge; and exhibiting appearances refembling those which the electric matter is known to prefent, in our experiments made on it, in vacuo.

Thefe are the principal outlines of the Author's hypothefis. The paper itself is thort, and aphoriftical; and is faid to have been read to the Royal Academy of Sciences at Paris, at their meeting after Eafter last year. The Editor has added to it feveral ingenious notes, confifting of illuftrations, queries, fpeculations, &c. and has hazarded a new conjecture on the fubject. For this, however, as well as many other pieces of the Author not noticed by us, we must refer our Readers to the volume itself; not without expreffing our hopes that the ingenious

The Author had long ago obferved, that ice, in America, would not conduct a fhock. He does not feem to have been acquainted with the late fingular experiments on this fubject, made by M. Achard; who found that, in a very confiderable degree of cold, ice acquired electric qualities nearly approaching thofe of glafs; fo as even to bear a charge, &c.

Editor will proceed in the pious task of collecting the remaining valuable relics-for many fuch, we are told, exift-of one for whom he expresses so great and well founded a veneration. B...y.

ART. V. PHILOSOPHICAL TRANSACTION of the Royal Society of London. Vol. LXIX. Part 1. For the Year 1779. 4:0. 7 s. 6d. fewed. Davis. 1779.

IT

MUSIC.

T is fortunate that the gifted mufical infant, who is the fubject of this curious Article, fhould meet with a cotemporary hiftorian fo well qualified, and fo extenfively and advantageoufly known in the literary world, as Dr. Burney, to record his marvellous mufical talents and attainments, to which he has himself been an eye-witnefs. Having had repeated opportunities of hearing and studying this extraordinary child; and after having afcertained his age by a recourfe to the parish register; he prefaces his own obfervations on him by a relation, among others, of the following extraordinary facts, preceding his acquaintance with him; and thefe are founded on evidence, the authenticity of which cannot reasonably be difputed.

When he was only a year and a half old, he would leave his food to attend to an organ built by his father; a plain man, who could barely play a few eafy tunes upon it: and when he was two years old, he had acquired fuch a knowledge of the conftruction of that inftrument, or of the fituation of the keys of it, as to touch the key-note of his favourite tunes, in order to point out the particular tune which he wanted his father to play to him. Soon after this, he would ftrike the two or three first notes of a tune, not being able to name it, when he thought that the key-note alone did not fufficiently explain which he wifhed to have played.

At the precife age of two years and three weeks, he, on a fudden, commenced practical mufician himself, to the great furprize of his father, then working in a room above; and who, on coming immediately down ftairs, heard and faw him playing (affifted by an elder brother, whom he had engaged to blow the bellows) the first part of God fave great GEORGE our King: -a melody, which had the most frequently been administered to him as a narcotic by his mother, during the first year of his life,' and which he had often been accustomed to hear his father play. It seems too that his nerves, by this time on the full ftretch, had been exceffively agitated, on hearing the fuperior performance of Mrs. Lulman, a mufical lady, who came to try his father's organ.

The next day, fays Dr. Burney, he made himself mafter of the treble of the fecond part; and, the day after, he attempted the bafe, which he performed nearly correct in every particular, REV. Mar. 1780.

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except

except the note immediately before the clofe; which being an octave below the preceding found, was out of the reach of his litele hand.'

When he was two years and four months old, (in November 1777) having heard a voluntary performed on his father's organ, by Mr. Mully, a mufic-mafter; as foon as he was gone, the child feeming to play on the organ in a wild and different manner from what his mother was accustomed to hear, fhe afked him what he was doing? And he replied, "I am play ing the gentleman's fine thing." But fhe was unable to judge of the resemblance: however, when Mr. Mully returned a few days after, and was afked, whether the child had remembered any of the paffages in his voluntary, he answered in the affirmative;-and for a confiderable time after, he would play nothing else but these paffages."

At this time, fays Dr. Burney, fuch was the rapid progrefs he made in judging of the agreement of founds, that he played the Easter-Hymn with full harmony; and in the last two or three bars of Hallelujah, where the fame found is fuftained, he played chords with both hands, by which the parts were multipled to fix, which he had great difficulty in reaching on account of the fhortnefs of his fingers.'-In making a base to tunes which he had recently caught by his ear, whenever the harmony displeafed him, he would continue the treble note till be had formed a better accompaniment."

When Dr. Burney heard him, we apprehend he was about three years and three or four months old. About this time, on first hearing the voice of Signior Pacchierotti, he did not feem fenfible of the fuperior tafte and refinement of that exquifite performer ;-refinements indeed are not to be expected in the infancy of any art :-but he called out very foon after the air was begun-" He is finging in F."-This, adds Dr. Burney, one of the aftonishing properties of his ear, that he can diftinis guish at a great distance from any inftrument, and out of fight of the keys, any note that is ftruck, whether A, B, C, &c, In this I have repeatedly tried him, and never found him miftaken even in the half notes; a circumftance the more extraordinary, as many practitioners and good performers are unable to diftinguish by the ear, at the opera or elsewhere, in what key any air or piece of mufic is executed.

But this child, Dr. Burney obferves, was able to find any note that was ftruck in his hearing, when out of fight of the keys, at two years and a half old, even before he knew the letters of the alphabet.-This faculty accidentally discovered itself in January 1778. While his father was playing the organ, a particular note hung, or in the organ-builders language, ciphered; fo that the tone was continued without the preffure of

the

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