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of the Island, but was new among them. I hear the minister at Southhold is esteemed an ingenious man; perhaps you may know him, and he will at your request favor me with an explicit account of these fences.

The fore part of the summer here was extremely dry, and the grass in many places was burnt up. But we had a good crop of wheat; and, rains coming on about the end of July, we had in August a new spring, the grass sprouting again wonderfully thick and fast, in fields where we thought the very roots had been destroyed. Our grave-diggers said they found the earth hot sensibly at three feet depth, even after these rains; perhaps the great heat below, and the moisture above, occasioned this sudden and profuse vegetation, the whole country being, as it were, one great hot-bed. I am, with esteem and affection, dear Sir, Your obliged humble servant,

B. FRANKLIN.

DEAR SIR,

TO JARED ELIOT.

Remarks on Husbandry.

Philadelphia, 10 December, 1751.

The rector of our Academy, Mr. Martin, came over to this country on a scheme for making potash, in the Russian method. He promised me some written directions for you, which expecting daily, I delayed writing, and now he lies dangerously ill of a kind of quinsy. The surgeons have been obliged to open his windpipe, and introduce a leaden pipe for him to breathe through. I fear he will not recover.

I thank you for the merino wool. It is a curiosity. Mr. Roberts promises me some observations on husbandry for you. It is one Mr. Masters, that makes manure of leaves, and not Mr. Roberts. I hope to get the particulars from him soon.

I have a letter from Mr. Collinson, of July 19th, in which he says; "Pray, has Mr. Eliot published any addition to his work? I have Nos. 1 and 2. If I can get ready, I will send some improvements made in the sandy parts of the county of Norfolk. By the way, it is a great secret, but it is Mr. Jackson's own drawing up, being experiments made on some of his father's estates in that county; but his name must not be mentioned. I thank you for the fowl meadow grass. sowed it June 7th, as soon as I received, it, but none is yet come up. I don't know how it is, but I never could raise any of your native grasses; and I have had a variety from J. Bartram of curious species."

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In another, of September 26th, he says, "I am much obliged to thee for Mr. Eliot's Third Essay. I have sent Maxwell's 'Select Transactions in Husbandry.' If Mr. Eliot has not seen them, they may be very useful to him. I have prevailed on our worthy, learned, and ingenious friend Mr. Jackson to give some dissertations on the husbandry of Norfolk, believing it may be very serviceable to the colonies. He has great opportunities of doing this, being a gentleman of leisure and fortune, being the only son, whose father has great riches and possessions, and resides every year, all the long vacation, at his father's seat in Norfolk. After J. Bartram has perused it, I shall submit how it may be further disposed of, only our friend Eliot should see it soon; for Jackson admires his little Tracts of Husbandry, as well as myself, and it may be of greater service to him and his colony, than to yours." "The fowl meadow

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grass has at last made its appearance. Another year we shall judge better of it." Thus far friend Collinson. You may expect the papers in a post or two. If you make any use of them, you will take care not to mention any thing of the author.

The bearer is my son, who desired an opportunity of paying his respects to you in his return from Boston. He went by sea.

They have printed all my electrical papers in England, and sent me a few copies, of which I design to send you one per next post, after having corrected a few errata. I am, dear Sir,

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I received yours of the 23d of April,* as I was going on board the sloop, on my return home from New York, and could not take the pleasure of reading it before I left that place.

One so much conversant in examining any particular phenomenon, or various phenomena issuing from the same cause, must on every occasion give the pleasure of learning something new to those less conversant in them, as often as the former is pleased to answer any objections made by the latter, or explain the diversities which attend the same phenomenon in different cases or appearances.

* See this letter in Vol. V. p. 283.

Your conjecture of the electric fluid's taking place in the superior regions of the atmosphere pleases my fancy, as it in some measure confirms what I have advanced in the treatise now in the press, viz. that all the planets, in a greater or less degree, emit light, and indeed, I think, all bodies do. It does not follow, that, because we do not see the light, none is emitted. Some men can see where others are entirely in the dark; and some animals, as owls, bats, &c., see in the dark, and cannot bear so great a degree of light as is necessary for our perceptions.

When you shall see that tract you will have opportunity of judging of the validity of the reasons I ad vance for an opinion, that light is a substance or being essentially distinct from what we commonly call matter or body; that they have nothing in common between them, except that we consider or conceive both as consisting of quantity, that is, that in the same space there may be a greater or less quantity of either, and that a certain quantity of either may be confined within certain bounds, and consequently have some shape or form. Light has no power of attraction, though it be attracted by resisting matter. The vibrations of a fluid will in no manner explain the phenomena of light, as is very expressly pointed out in Sir Isaac Newton's Optics; for example, "Light proceeds always in straight lines, unless diverted by some other thing; for this reason, any opaque body placed between the eye and a luminous body intercepts all the light; but it does not intercept the sound coming from a sonorous body, because sound is conveyed by the vibration of a fluid medium, not by any emission of particles from the sounding body." Again, the separation of the distinct parts of light, which excite in us the different and distinct sensations of colors, and which, once separated

always remain the same, proves that these sensations cannot be produced by the vibrations of any medium supposed to convey the action of light from the luminous body. I am persuaded, that a careful attention to the phenomena in Sir Isaac's Optics, and to his reflections on them, will remove all doubt on this head.

On this occasion I think it proper to observe to you, that, in the treatise before mentioned, what Sir Isaac has proved is generally taken for granted and supposed to be known.

It may be proper likewise to observe to you, that pure light, without any other mixture, makes no impression on any other sense except the sight; that the sense of heat arises from the action of light united with the action of some resisting matter. So, likewise, we have no idea of fire without the union of resisting matter with light.

In considering all quantities or degrees of action or force, whether in ascending or descending, whether in considering them as continually increasing or as continually decreasing, the ratio of comparison must at last come to that of infinity. We have no idea of the absolute force of any thing, only of its comparative force or ratio of its force to that of some other thing. The force of different quantities of light does not arise from the different velocities, (for I suppose all light always moves in the same ratio of velocity,) but from the greater quantity or density of light in the same space.

If the emission of light be not continued but by distinct vibrations or pulses, and an infinitely thin surface of light be thrown off in any finite part of time, suppose in a fifth, then there cannot be any finite or determinable diminution of the light of the sun, or of the diameter of the light in the sun, in any finite time. If the intervals of the vibrations or emissions of infinitely

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