nature. But I find it has been long known in the east. Bernier, in the account of his travels into India, written above a hundred years since, mentions the custom of travellers carrying their water in flasks covered with wet wrappers, and hung to the pommels of their saddles, so as that the wind might act upon them, and so cool the water. I have also seen a kind of jar for cooling water, made of potter's earth glazed, and so porous that the water gradually oozed through to the surface, supplying water just sufficient for a constant evaporation. I tried it and found the water within much cooler in a few hours. This jar was brought from Egypt.

FROM JOHN CANTON TO B. FRANKLIN.*

The Melting of Metals by Lightning not a cold Fusion. - Compressibility of Water and other Fluids.

London, 29 June, 1764.

DEAR SIR, Your favor of the 14th of March came to my hands the 15th of May last, and gave me great pleasure. The first experiment of Mr. Kinnersley's, which you mention, is, as you observe, a beautiful one to see; and,

Mr. Canton was a very ingenious experimental philosopher, and for many years an active and valuable member of the Royal Society. His papers in the Philosophical Transactions, and other publications, contributed much to the improvement of science. His fondness for electricity was the cause of an intimate friendship between him and Dr. Franklin, which continued till the death of Mr. Canton, on the 22d of March, 1772, in the fifty-fourth year of his age. His most important discovery was that of the compressibility of water, in opposition to the received opinion formed on the celebrated Florentine experiment. For this discovery he was honored by the Royal Society with the Copley Medal, in November, 1765.- EDITOR.

I think, fully proves that the fusion of metals by lightning is not a cold fusion. I have myself several times melted small brass wire by a stroke from your case of bottles, which left a mark where it lay upon the table, and some balls of twice or three times its diameter near the mark, but no part of the wire could be found. At the time of the stroke a great number of sparks, like those from a flint and steel, fly upward and laterally from the place where the wire was laid, and lose their light in the daytime, at the distance of about two or three inches. The diameter of a piece of Mr. Kinnersley's wire, which you were so kind as to send me with the balls, I found to be one part in one hundred and eighty-two of an inch; mine was but one part in three hundred and thirty.

The second of Mr. Kinnersley's experiments, which you relate, and which seems to be a very extraordinary one, I have several times endeavoured to make, but without success. The air with you must certainly be much drier than in England; for I have never observed the enclosed pith-balls to separate by the electrized air of a room, without having first heated the phial, notwithstanding which, they always came together in the phial, before the outward air had lost its electricity, as appears by their separating again when taken out of it. I once electrified the air of my largest room to a considerable degree, and by opening the windows and doors suffered the wind to blow through for about five minutes. I then shut them and examined the air in the room, but found no sign of electricity remaining. This air I electrified to about the same degree as before, and, leaving it confined, it retained a sensible degree of its electricity for more than three quarters of an hour. Hence I entirely agree with you, that the glass in Mr. Kinnersley's

experiment received some degree of electricity from the electrized air, and so kept the balls separated after that air was blown away.

I have put your ingenious friend Mr. Bowdoin's telescope into Mr. Nairne's hands, who is making a pedestal for it, which I think will be an improvement of that which Mr. Bowdoin has described in his last letter to me, which you saw. You may depend on my taking all possible care to get it well executed and soon. I find the fitting Dollond's micrometer to the telescope is impracticable.

Since the publication of a short paper in the Transactions, which contains an account of experiments to prove that water is not incompressible, I have discovered a remarkable property belonging to that fluid, which is new to me, though perhaps it may not be so to you. The property I mean is, its being less compressible in summer than in winter. This is contrary to what I find in spirit of wine and oil of olives, which are (as one would expect water to be) more compressible when expanded by heat, and less so when contracted by cold. For, when Fahrenheit's thermometer is at thirty-four degrees and the barometer at twentynine and a half, water is compressed by the weight of the atmosphere forty-nine parts in a million of its whole bulk, and spirit of wine sixty of the same parts. When the thermometer is at fifty degrees, water is compressed forty-six parts and spirit of wine sixty-six parts in a million by the same weight; and, when the thermometer is at sixty-four degrees, this weight will compress water no more than forty-four parts, but it will compress spirit of wine seventy-one of these parts.

As I am not able at present to account for this difference in the compressibility of water myself, I should be very glad to have your thoughts upon it.

The compression by the weight of the atmosphere, and the specific gravity, of the following fluids (which are all that I have yet tried) are set down as they were found in a temperate degree of heat, and when the barometer was at a mean height.

You will easily perceive that the compressions of these fluids by the same weight are not in the inverse ratio of their densities, or specific gravities, as might be expected. The compression of spirit of wine, for instance, being compared with that of rain water, is greater than in this proportion it ought to be, and the compression of sea water is less.

Mr. Price, Mr. Rose, Mr. Cooper, and the rest of the club, desire their most respectful compliments to you, and very much regret, as I do myself, your leaving England.

I am, with the most sincere regard,

Dear Sir, &c.

JOHN CANTON.

those difficulties, have little or no pleasure in hearing this music. Many pieces of it are mere compositions of tricks. I have sometimes, at a concert, attended by a common audience, placed myself so as to see all their faces, and observed no signs of pleasure in them during the performance of a great part that was admired by the performers themselves; while a plain old Scotch tune, which they disdained, and could scarcely be prevailed on to play, gave manifest and general delight.

Give me leave, on this occasion, to extend a little the sense of your position, that "melody and harmony are separately agreeable, and in union delightful," and to give it as my opinion, that the reason why the Scotch tunes have lived so long, and will probably live for ever (if they escape being stifled in modern affected ornament), is merely this, that they are really compositions of melody and harmony united, or rather that their melody is harmony. I mean the simple tunes sung by a single voice. As this will appear paradoxical, I must explain my meaning. In common acceptation, indeed, only an agreeable succession of sounds is called melody, and only the coexistence of agreeable sounds, harmony, But, since the memory is capable of retaining for some moments a perfect idea of the pitch of a past sound, so as to compare with it the pitch of a succeeding sound, and judge truly of their agreement or disagreement, there may and does arise from thence a sense of harmony between the present and past sounds, equally pleasing with that between two present sounds.

Now the construction of the old Scotch tunes is this, that almost every succeeding emphatical note is a third, a fifth, an octave, or in short some note that is in concord with the preceding note. Thirds are chiefly used, which are very pleasing concords. I use the word emphatical to distinguish those notes which have a