Imágenes de páginas
PDF
EPUB

east. It spoiled the corn,' which was of some height, in a circle of about twenty feet in diameter. That near the centre was burnt down to the roots, as I was informed by the owner. I did not hear of it till some days after, and when I saw the place it had been replanted with cabbages. The corn near the circumference of the circle was only scorched, and I saw the leaves withered and drooping. The place struck was about midway between a tree on one side and the well-pole and chimney of the house on the other, and as I judge about eighty feet distant from each; and there was nothing near so high on the other sides for a considerable distance. Hence, their protection did not extend eighty feet. If a person had been standing in that corn, I suppose there is no doubt that he would have been killed. And therefore a person in the midst of an open plain is by no means secure from the stroke of lightning. The best security seems to be to have something high, as a tree, for example, near him, but not too near; perhaps from thirty or forty to ten or fifteen feet, or rather to be near two such trees.

I am, etc.,

JOHN WINTHROP.

CCCCLXXXVIII

TO MRS. JAMES MECOM

LONDON, 9 March, 1773.

DEAR SISTER:-I received your kind letter of December 30th, and rejoice to find you were well. I

1 Indian corn, or maise, which is most commonly planted in this neighborhood.

may, possibly, have the greater pleasure of seeing you before the year is out. I have desired Cousin Williams to give you the money he may recover from Hall. I would only mention to you that when I was in Boston in 175 [mutilated] brother John then living, an old man, whose name I have forgotten, applied to me with a bond of our father's of about fifteen or seventeen pounds, if I remember right, desiring I would pay it, which I declined, with this answer, that as I had never received any thing from the estate, I did not think myself obliged to pay any of the debts. But I had another reason, which was that I thought the care of those matters belonged more properly to my brother. If you know that person, I wish you would now, out of Hall's money, pay that debt; for I remember his mildness on the occasion with some regard.

My love to Jenny. I am ever,
Your affectionate brother,

B. FRANKLIN.

I have not yet seen Capt. Jenkins, but will inquire him out when I next go to the city.

CCCCLXXXIX

TO THOMAS CUSHING

LONDON, 9 March, 1773.

SIR: I did myself the honor of writing to you on the 2d of December and the 5th of January past. Since which I have received your favor of November

28th, enclosing the Votes and Proceedings of the Town of Boston, which I have reprinted here, with a preface. Herewith I send you a few copies.

Governor Hutchinson's speech, at the opening of your January session, has been printed and industriously circulated here by (as I think) the ministerial people, which I take to be no good sign. The Assembly's answer to it is not yet arrived, and, in the meanwhile, it seems to make impression on the minds of many not well acquainted with the dispute. The tea duty, however, is under the consideration of Parliament, for a repeal, on a petition from the East India Company, and no new measures have been talked of against America, or are likely to be taken during the present session. I was therefore preparing to return home by the spring ships, but have been advised by our friends to stay till the session is over; as the commission sent to Rhode Island, and discontents in your province, with the correspondence of the towns, may possibly give rise to something here, when my being on the spot may be of use to our country. I conclude to stay a little longer. In the meantime I must hope that great care will be taken to keep our people quiet; since nothing is more wished for by our enemies than, by insurrections, we should give a good pretence for increasing the military among us and putting us under more severe restraints. And it must be evident that, by our rapidly increasing strength, we shall soon become of so much importance that none of our just claims of privilege will be, as heretofore, unattended to, nor any security we can wish for our rights be

denied us. With great respect, I have the honor to

be, etc.,

CCCCXC

TO M. DUBOURG

B. FRANKLIN.

LONDON, 10 March, 1773.

SIR:-As to the magnetism which seems produced by electricity, my real opinion is that these two powers of nature have no affinity with each other, and that the apparent production of magnetism is purely accidental. The matter may be explained

thus:

Ist. The earth is a great magnet.

2dly. There is a subtile fluid, called the magnetic fluid, which exists in all ferruginous bodies, equally attracted by all their parts, and equally diffused through their whole substance; at least where the equilibrium is not disturbed by a power superior to the attraction of the iron.

3dly. This natural quantity of the magnetic fluid, which is contained in a given piece of iron, may be put in motion so as to be more rarefied in one part and more condensed in another; but it cannot be withdrawn by any force that we are yet made acquainted with, so as to leave the whole in a negative state, at least relatively to its natural quantity; neither can it be introduced so as to put the iron into a positive state, or render it plus. In this respect, therefore, magnetism differs from electricity.

4thly. A piece of soft iron allows the magnetic fluid which it contains to be put in motion by a moderate force; so that, being placed in a line with the magnetic pole of the earth, it immediately acquires the properties of a magnet, its magnetic fluid being drawn or forced from one extremity to the other; and this effect continues as long as it remains in the same position, one of its extremities becoming positively magnetized, and the other negatively. This temporary magnetism ceases as soon as the iron is turned east and west, the fluid immediately diffusing itself equally through the whole iron, as in its natural state.

5thly. The magnetic fluid in hard iron, or steel, is put in motion with more difficulty, requiring a force greater than the earth to excite it; and, when once it has been forced from one extremity of the steel to the other, it is not easy for it to return; and thus a bar of steel is converted into a permanent magnet.

6thly. A great heat by expanding the substance of this steel and increasing the distance between its particles, affords a passage to the magnetic fluid, which is thus again restored to its proper equilibrium; the bar appearing no longer to possess magnetic virtue.

7thly. A bar of steel, which is not magnetic, being placed in the same position, relatively to the pole of the earth, which the magnetic needle assumes, and in this position being heated and suddenly cooled, becomes a permanent magnet. The reason is, that while the bar was hot, the magnetic

« AnteriorContinuar »