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have not a copy of what I sent. If what you received before is not printed in the Philosophical Transactions, please to request Mr. Maskelyne to insert them as they are now sent, unless he should think it better to abridge or alter them, as to their dress or form, which he has full liberty to do, as he is much better acquainted with publications of this kind than I can be supposed to be.

I mentioned to our Society your proposal to purchase the Transactions of the learned societies in Europe, and they have taken the matter under their consideration. They approved of your reasoning on the subject, when I read it to them; and nothing will prevent their coming into the resolution, if their poverty does not.

I hope, that before this time Mr. Maskelyne has given you an estimate of the expense and apparatus necessary for erecting an observatory here, where we are blessed with so happy a serenity of air for astronomical observations. I have not yet mentioned this matter to our Society, but wait until I hear farther from you; and would still choose, that, when proposed, it should come from you and the Astronomer Royal, to whose judgment our Society pay the greatest respect in these matters.

Please to accept of my hearty thanks for the perusal of your last volume of the Philosophical Transactions. I shall deliver it safely to Mrs. Franklin.

When the observations of the transit of Venus come to hand from the East Indies, the North of Europe, or from South America, I shall be much obliged to you for a copy of them, as I am anxious to know how they correspond with ours.

I am, Sir, your most obedient and very humble servant,

JOHN EWING.

P. S. Please to deliver one of the copies with my compliments to the Astronomer Royal, the Reverend Mr. Maskelyne.

TO SAMUEL RHOADS.

On securing Houses from Fire.

London, 26 June, 1770. DEAR FRIEND, It is a long time since I had the pleasure of hearing from you directly. Mrs. Franklin has indeed now and then acquainted me of your welfare, which I am always glad to hear of. It is, I fear, partly, if not altogether my fault, that our correspondence has not been regu larly continued. One thing I am sure of, that it has been from no want of regard on either side, but rather from too much business, and avocations of various kinds, and my having little of importance to communicate.

One of our good citizens, Mr. Hillegas, anxious for the future safety of our town, wrote to me some time since, desiring I would inquire concerning the covering of our houses here with copper. I sent him the best information I could then obtain, but have since received the enclosed from an ingenious friend, who is what they call here a civil engineer. I should be glad you would peruse it, think of the matter a little and give me your sentiments of it. When you have done with the paper, please to give it to Mr. Hillegas. I am told by Lord Despencer, who has covered a long piazza, or gallery, with copper, that the expense is charged in this account too high; for his cost but one shilling and ten pence per foot, all charges included. I

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suppose

copper

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must have been thinner. And, indeed, it is so strong a metal, that I think it may well be used very thin.

It appears to me of great importance, to build our dwellinghouses, if we can, in a manner more secure from danger by fire. We scarcely ever hear of fire in Paris. When I was there I took particular notice of the construction of their houses, and I did not see how one of them could well be burnt. The roofs are slate or tile, the walls are stone, the walls generally lined with stucco or plaster, instead of wainscot, the floors of stucco, or of six square tiles painted brown, or of flag stone, or of marble ; if any floors were of wood, it was of oak wood, which is not so inflammable as pine. Carpets prevent the coldness of stone or brick floors offending the feet in winter, and the noise of treading on such floors overhead, is less inconvenient than on boards.

The stairs too, at Paris, are either stone or brick, with only a wooden edge or corner for the step; so that on the whole, though the Parisians commonly burn wood in their chimneys, a more dangerous kind of fuel than that used here, yet their houses escape extremely well, as there is little in a room that can be consumed by fire except the furniture ; whereas in London, perhaps scarcely a year passes in which half a million of property and many lives are not lost by this destructive element. Of late, indeed, they begin here to leave off wainscoting their rooms, and instead of it cover the walls with stucco, often formed into pannels like wainscot, which, being painted, is very strong and warm. Stone staircases too, with iron rails, grow more and more into fashion here; but stone steps cannot, in some circumstances, be fixed; and there, methinks, oak is safer than pine ; and I' assure you, that in many genteel houses here, both old and new, the stairs and floors are oak, and look extremely well. Perhaps solid oak

for the steps would be still safer than boards; and two steps might be cut diagonally out of one piece.

Excuse my talking to you on a subject with which you must be so much better acquainted than I am. It is partly to make out a letter, and partly in hope, that, by turning your attention to the point, some methods of greater security in our future building may be thought of and promoted by you, whose judgment I know has deservedly great weight with our fellowcitizens. For, though our town has not hitherto suffered very greatly by fire, yet I am apprehensive, that some time or other, by a concurrence of unlocky circumstances, such as dry weather, hard frost, and high winds, a fire then happening may suddenly spread far and wide over our cedar roofs, and do us an immense mischief. I am, yours, &c.

B. FRANKLIN.

Paper referred to in the preceding Letter.

The carpentry of the roof, being formed with its proper descents, is, in the first place, sheeted or covered with deals, nailed horizontally upon the rafters, after the same manner as when intended to be covered with lead. The sheets of the copper for this covering are two feet by four, and for covering the slopes of the roof are cast so thin, as to weigh eight or nine pounds, and for covering the flats or gutters, ten or eleven pounds each, or about one pound, or a pound and a quarter, to the superficial foot.

A string of strong cartridge paper (overlapping a little at its joints) is regularly tacked down upon the sheeting, under the copper covering, as the work proceeds from eaves to ridge. It prevents the jingling sound of hail or rain falling upon the roof, and answers another purpose to be mentioned by and by.

In order to show the regular process of laying down .the roof, we must begin with fastening two sheets together lengthwise. The edges of two sheets are laid down so as to lap or cover each other an inch, and a slip of the same copper, about three inches and a half broad, called the reeve, is introduced between them. Four oblong holes, or slits, are then cut or punched through the whole, and they are fastened or riveted together by copper nails, with small round shanks and flat heads. Indents are then cut one inch and three quarters deep upon the seam at top and bottom. The right-hand sheet and the reeve are then folded back to the left. The reeve is then folded to the right, and the sheets being laid on the roof in their place, it is nailed down to the sheeting with flat-headed, short copper nails. The right hand sheet is then folded over the reeve to the right, and the whole beat down flat upon the cartridge paper covering the sheeting, and thus they are fastened and laid in their places, by nailing down the reeve only; and by reason of the oblong holes through them and the reeve, have a little liberty to expand or contract with the heat and cold, without raising themselves up from the sheeting, or tearing themselves or the fastening to pieces.

Two other sheets are then fixed together, according to the first and second operations above, and their seam, with the reeve, introduced under the upper ends of the seam of the former, so as to cover down about two inches upon the upper ends of the former sheets; and so far the cartridge paper is allowed to cover the two first sheets. This edge of the paper is dipped in oil, or in turpentine, so far before its application, and thus a body between the sheets is formed impenetrable to wet, and the reeve belonging to the two last sheets is nailed down to the sheeting as before, and the left

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