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as draw off the electrical fire ; lay a long freely on fine wire axles. Also by little sharp needle upon the shot, and you cannot wheels of the same matter, but formed like electrise the shot so as to make it repel the water-wheels. Of the disposition and applia cork-ball. -Or fix a needle to the end of a cation of which wheels, and the various phesuspended gun-barrel, or iron-rod, so as to nomena resulting, I could, if I had time, fill point beyond it like a little bayonet ;* and you a sheet.* The impossibility of electrising while it remains there, the gun-barrel, or rod, one's self (though standing on wax) by rubcannot by applying the tube to the other end bing the tube, and drawing the fire from it; be electrised so as to give a spark, the fire and the manner of doing it, by passing the continually running out silently at the point. tube near a person or thing standing on the In the dark you may see it make the same floor, &c. had also occurred to us some months appearence as it does in the case before-men- before Mr. Watson's ingenious Sequel came tioned.

to hand, and these were some of the new The repellency between the cork-ball and things I intended to have communicated to the shot is likewise destroyed. 1. By sifting you. But now I need only mention some fine sand on it; this does it gradually. 2. By particulars not hinted in that piece, with our breathing on it. 3. By making a smoke about reasonings thereupon: though perhaps the latit from burning wood.t 4. By candle-light, ter might well enough be spared. even though the candle is at a foot distance: 1. A person standing on wax, and rubbing these do it suddenly.-The light of a bright the tube, and another person on wax drawing coal from a wood fire, and the light of a red the fire, they will both of them (provided they hot iron do it likewise ; but not at so great a do not stand so as to touch one another) appear distance. Smoke from dry rosin dropt on hot to be electrised, to a person standing on the iron, does not destroy the repellency; but is floor; that is, he will perceive a spark on apattracted by both shot and cork ball, forming proaching each of them with his knuckle. proportionable atmospheres round them, mak- 2. But if the persons on wax touch one ing them look beautifully, somewhat like some another during the exciting of the tube, neiof the figures in Burnet's or Whiston's The-ther of them will appear to be electrised. ory of the Earth.

1 3. If they touch one another after exciting N. B. This experiment should be made in the tube, and drawing the fire as aforesaid, a closet, where the air is very still, or it will there will be a stronger spark between them be apt to fail.

than was between either of them and the perThe light of the sun thrown strongly on son on the floor. both cork and shot by a looking-glass for al 4. After such strong spark, neither of them long time together, does not impair the re- discover any electricity. pellency in the least. This difference between These appearances we attempt to account fire-light and sun-light is another thing that for thus : we suppose, as aforesaid, that elecseems new and extraordinary to us. I

trical fire is a common element, of which We had for some time been of opinion, that every one of the three persons abovemen. the electrical fire was not created by friction, tioned has his equal share, before any operabut collected, being really an element diffus- tion is begun with the tube. A, who stands ed among, and attracted by other matter, par- on wax, and rubs the tube, collects the electicularly by water and metals. We had even trical fire from himself into the glass; and discovered and demonstrated its afflux to the his communication with the common stock electrical sphere, as well as its efflux, by being cut off by the wax, his body is not again means of little light windmill wheels made of immediately supplied. B, (who stands on stiff paper vanes, fixed obliquely, and turning wax likewise) passing his knuckle along near

the tube, receives the fire which was collect• This was Mr. Hopkinson's experiment, made with an expectation of drawing a more sharp and powerful spark from the point. as from a kind of focus, and he

cut off, he retains the additional quantity rewas surprised to find little or none.

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smoke, being first attracted and then repelled, carries

pear to be electrised : for he having only the off with it a portion of the electrical fire; but that the same still subsists in those particles, till they communi.

| middle quantity of electrical fire, receives a cate it to something else, and that it is never really de. spark upon approaching B, who has an over stroyed. So when water is thrown on common fire, we do not imagine that the element is thereby de.

quantity ; but gives one to A, who has an unannihilated, but only dispersed, each particle | der quantity. If A and B approach to touch of water carrying off in vapour its portion of the fire.

| each other, the spark is stronger, because the which it had attracted and attached to itself.

I This different effect probably did not arise from difference between them is greater; after any difference in the light, but rather from the parti. cles separated from the candle, being first attracted and * These experiments with the wheels, were made and then repelled, carrying off the electric matter with them; communicated to me by my worthy and ingenious and from the rarefying of the air, between the glowing friend Mr Philip Syng; but we afterwards discovered coal or red hot iron, and the electrised shot, through that the motion of those wheels was not owing to any shich rarefied air the electric fluid could more readily afflux or efflux of the electric fluid, but to various circumpass.

stances of attraction and repulsion. 1750.

such touch- there is no spark between either there will be a small spark; but when their of them and C, because the electrical fire in lips approach, they will be struck and shockall is reduced to the original equality. If they ed; the same if another gentleman and lady, touch while electrising, the equality is never C and D, standing also on wax, and joining destroyed, the fire only circulating. Hence hands with A and B, salute or shake hands. have arisen some new terms among us; we We suspend by find silk thread a counterfeit say B, (and bodies like circumstanced) is spider, made of a small piece of burnt cork, electrised positively; A, negatively. Or ra- with legs of linen thread, and a grain or two ther, B is electrised plus ; A, minus. And of lead stuck in him, to give him more weight; we daily in our experiments electrise bodies upon the table, over which he hangs, we plus or minus, as we think proper.—To elec- stick a wire upright, as high as the phial and trise plus or minus, no more needs to be wire, four or five inches from the spider; known than this, that the parts of the tube or, then we animate him, by setting the electrisphere that are rubbed, do, in the instant of fied phial at the same distance on the other the friction, attract the electrical fire, and side of him ; he will immediately fly to the therefore take it from the thing rubbing : wire of the phial, bend his legs in touching it, the same parts immediately, as the friction then spring off, and fly to the wire on the taupon them ceases, are disposed to give the ble, thence again to the wire of the phial, fire they have received, to any body that has playing with his legs against both, in a very less. Thus you may circulate it, as Mr. Wat- entertaining manner, appearing perfectly son has shown; you may also accumulate or alive to persons unacquainted : he will consubtract it, upon, or from any body, as you tinue this motion an hour or more in dry weaconnect that body with the rubber or with the ther. We electrify, upon wax in the dark, receiver, the communication with the common a book that has a double line of gold round stock being cut off. We think that ingenious upon the covers, and then apply a knuckle gentleman was deceived when he imagined to the gilding; the fire appears every where (in his Sequel) that the electrical fire came upon the gold like a flash of lightning ; not down the wire from the ceiling to the gun- upon the leather, nor, if you touch the leather barrel, thence to the sphere, and so electrised instead of the gold. We rub our tubes with the machine and the man turning the wheel, buckskin, and observe always to keep the &c. We suppose it was driven off, and not same side to the tube, and never to sully the brought on through that wire; and that the tube by handling; thus they work readily machine and man, &c. were electrised minus; and easily, without the least fatigue, especii. e. had less electrical fire in them than things ally if kept in tight pasteboard cases, lined in common.

with flannel, and sitting close to the tube.* As the vessel is just upon sailing, I cannot This I mention, because the European papers give you so large an account of American on electricity frequently speak of rubbing the electricity as I intended : I shall only men- tube as a fatiguing exercise. Our spheres tion a few particulars more.- We find granu- are fixed on iron axles, which pass through lated lead better to fill the phial with, than them. At one end of the axis there is a small water, being easily warmed, and keeping handle, with which you turn the sphere like warm and dry in damp air.-We fire spirits a common grindstone. This we find very comwith the wire of the phial.-We light can- modious, as the machine takes up but little dles just blown out, by drawing a spark room, is portable, and may be inclosed in a among the smoke between the wire and snuf-tight box, when not in use. It is true, the fers.-We represent lightning, by passing sphere does not turn so swift as when the the wire in the dark, over a china plate that great wheel is used: but swiftness we think has gilt flowers, or applying it to gilt frames of little importance, since.a few turns will of looking glasses, &c.- We electrise a per- charge the phial, &c. sufficiently.* son twenty or more times running, with a

B. FRANKLIN. touch of the finger on the wire, thus: he stands on wax; give him the electrised bottle in his hand ; touch the wire with your finger, and then touch bis hand or face; there are

To Peter Collinson, London. sparks every time.* _We increase the force

Observations on the Leyden Bottle, with Erpeof the electrical kiss vastly, thus : let A and

riments proring the different electrical State B stand on wax; or A on wax, and B on the

of its different Surfaces. floor; give one of them the electrised phial

Philadelphia, Sept.1, 1747. in hand; let the other take hold of the wire ;

The necessary trouble of copying long let* By taking a spark from the wire, the electricity ters, which perhaps, when they come to your within the bottle is diminished; the outside of the bot. lle then draws some from the person holding it, and * Our tubes are made here of green glass, 27 or 30 leaves him in the negative state. Then when bis inches long, as big as can be grasped. hand or face is touched, an equal quantity is restored to This simple easily made machine was a contri him from the person touching.

vance of Mr. Syng's.

hands, may contain nothing new, or worth from the top, by touching the wire, unless an your reading, (so quick is the progress made equal quantity can at the same time get in with you in electricity) half discourages me at the bottom.* Thus, place an electrised from writing any more on that subject. Yet bottle on clean glass or dry wax, and you will I cannot forbear adding a few observations on not, by touching the wire, get out the fire M. Muschenbroek's wonderful bottle. from the top. Place it on a non-electric, and

1. The non-electric contained in the bottle touch the wire, you will get it out in a short differs, when electrised, from a non-electric time; but soonest when you form a direct electrised out of the bottle, in this; that the communication as above. electrical fire of the latter is accumulated on So wonderfully are these two states of elecits surface, and forms an electrical atinosphere tricity, the plus and minus, combined and baround it of considerable extent; but the elec-lanced in this miraculous bottle! situated and trical fire is crowded into the substance of the related to each other in a manner that I can former, the glass confining it.*

| by no means comprehend ! If it were possible 2. At the same time that the wire and the that a bottle should in one part contain a quantop of the bottle, &c. is electrised positively tity of air strongly comprest, and in another or plus, the bottom of the bottle is electrised part a perfect vacuum, we know the equilinegatively or minus, in exact proportion; i. e. brium would be instantly restored within. whatever quantity of electrical fire is thrown But here we have a bottle containing at the in at the top, an equal quantity goes out of the same time a plenum of electrical fire, and a bottom.Í To understand this, suppose the vacuum of the same fire; and yet the equicommon quantity of electricity in each part of librium cannot be restored between them but the bottle, before the operation begins, is equal by a communication without ! though the pleto 20; and at every stroke of the tube, sup- num presses violently to expand, and the hunpose a quantity equal to 1 is thrown in; then, gry vacuum seems to attract as violently in after the first stroke the quantity contained in order to be filled. the wire and upper part of the bottle will be 5. The shock to the nerves (or convulsion 21, in the bottom 19. After the second, the rather) is occasioned by the sudden passing of upper part will have 22, the lower 18, and so the fire through the body in its way from the on, till, after 20 strokes, the upper part will top to the bottom of the bottle. The fire takes have a quantity of electrical fire equal to 40, the shortestf course, as Mr. Watson justly obthe lower part none: and then the operation serves: but it does not appear from experiends: for no more can be thrown into the ment, that in order for a person to be shockupper part, when no more can be driven out ed, a communication with the floor is necesof the lower part. If you attempt to throw sary : for he that holds the bottle with one more in, it is spewed back through the wire, hand, and touches the wire with the other, or flies out in loud cracks through the sides of will be shocked as much, though his shoes the bottle.

be dry, or even standing on wax, as other3. The equilibrium cannot be restored in the wise. And on the touch of the wire, (or of bottle by inward communication or contact of the gun-barrel, which is the same thing) the the parts; but it must be done by a commu- fire does not proceed from the touching finger nication formed without the bottle, between to the wire, as is supposed, but from the wire the top and bottom, by some non-électric, to the finger, and passes through the body to touching or approaching both at the same the other hand, and so into the bottom of the tine ; in which case it is restored with a vio- bottle. lence and quickness inexpressible; or, touch

Experiments confirming the above. ing each alternately, in which case the equilibriuin is restored by degrees.

EXPERIMENT I. 4. As no more electrical fire oan be thrown Place an electrised phial on wax; a small into the top of the bottle, when all is driven cork-ball suspended by a dry silk thread held out of the bottom, so in a bottle not yet elec- in your hand, and brought near to this wire trised, none can be thrown into the top, when will first be attracted, and then repelled : none can get out at the bottom; which hap- when in the state of repellency, sink your pens either when the bottom is too thick or hand, that the ball may be brought towards when the bottle is placed on an electric per the bottom of the bottle; it will be there inse. Again, when the bottle is electrised, but stantly and strongly attracted, till it has partlittle of the electrical fire can be drawn out ed with its fire.

If the bottle had a positive electrical at* See this opinion rectified in sect. 16 and 17 of the mosphere, as well as the wire, an electrified next letter. The fire in the bottle was found by sub-cork would be repelled from one as well as sequent experiments not to be contained in the non. I from the other. electric, but in the glass, 1748. .

| What is said here, and after, of the top and bot: tom of the bottle, is true of the inside and outside sor. * See the preceding note, relating to top and bottom. faces, and should have been so expressed.

+ Other circumstances being equal

EXPERIMENT II.

EXPERIMENT VI. Fig. 1. From a bent wire (a) sticking in Place a man on a cake of wax, and present the table, let a small linen thread (6) hang him the wire of the electritied phial to touch, down within half an inch of the electrised you standing on the floor, and holding it in phial (c). Touch the wire or the phial re- your hand. As often as he touches it, he peatedly with your finger, and at every touch will be electrified plus ; and any one stand. you will see the thread instantly attracted ing on the floor may draw a spark from him. by the bottle. (This is best done by a vine- The fire in this experiment passes out of the gar cruet, or some such bellied-bottle.) As wire into him; and at the same time out of soon as you draw any fire out of the upper your hand into the bottom of the bottle. part, by touching the wire, the lower part of the bottle draws an equal quantity in by the

EXPERIMENT VII. thread.

Give him the electrical phial to hold ; and , EXPERIMENT III.

do you touch the wire; as often as you touch Fig. 2. Fix a wire in the lead, with which

it he will be electrified minus, and may draw

a spark from any one standing on the floor. the bottom of the bottle is armed (d) so as :

The fire now passes from the wire to you, and that bending upwards, its ring-end may be

from him into the bottom of the bottle. level with the top or ring-end of the wire in the cork (e) and at three or four inches dis

EXPERIMENT VIII. tance. Then electrise the bottle, and place

Lay two books on two glasses, back toit on wax. *If a cork suspended by a silk. thread (S) hang between these two wires, it',

wards back, two or three inches distant. Set will play incessantly from one to the other, till

îthe electrified phial on one, and then touch the bottle is no longer electrised; that is, it

the wire; that book will be electrified minus ; fetches and carries fire from the top to the

the electrical fire being drawn out of it by the bottom* of the bottle, till the equilibrium is

bottom of the bottle. Take off the bottle, and

holding it in your hand, touch the other with restored.

the wire; that book will be electrified plus; EXPERIMENT IV.

the fire passing into it from the wire, and the Fig. 3. Place an electrised phial on wax; bottle is at the same time supplied from your take a wire (g) in form of a C, the ends at hand. A suspended small cork-ball will play such a distance when bent, as that the up between these books till the equilibrium is per may touch the wire of the bottle, when I restored.. the lower touches the bottom: stick the outer

EXPERIMENT IX. part on a stick of sealing-wax (h,) which will

When a body is electrified plus, it will re. serve as a handle; then apply the lower end

pel a positively electrified feather or small to the bottom of the bottle, and gradually

cork-ball. When minus (or when in the bring the upper end near the wire in the cork.

common state) it will attract them, but The consequence is, spark follows spark till the equilibrium is restored. Touch the top

stronger when minus than when in the comfirst, and on approaching the bottom with the

mon state, the difference being greater. other end, you have a constant stream of fire

EXPERIMENT X. from the wire entering the bottle. Touch the top and bottom together, and the equilibrium

Though, as in Experiment VI, a man standwill instantly be restored, the crooked wire

ing on wax may be electrised a number of forthing the communication.

times by repeatedly touching the wire of an

electrised bottle (held in the hand of one EXPERIMENT V.

standing on the floor) he receiving the fire Fig. 4. Let a ring of thin lead, or paper, from the wire each time; yet holding it in surround a bottle (i) even at some distance his own hand, and touching the wire, though from or above the bottom. From that ring he draws a strong spark, and is violently let a wire proceed up, till it touch the wire shocked, no electricity remains in him; the of the cork (k). A bottle so fixed cannot by fire only passing through him, from the upany means be electrised: the equilibrium is per to the lower part of the bottle. Observe, never destroyed : for while the communica- before the shock, to let some one on the floor tion between the upper and lower parts of the touch him to restore the equilibrium in his bottle is continued by the outside wire, the body; for in taking hold of the bottom of the fire only circulates : what is driven out at bottle, he sometimes becomes a little elecbottom, is constantly supplied from the top.t trised minus, which will continue after the Hence a bottle cannot be electrised that is foul shock, as would also any plus electricity, or moist on the outside, if such moisture con- which he might have given him before the tinue up to the cork or wire.

shock. For restoring the equilibrium in the

bottle, does not at all affect the electricity * i. & From the inside to the outside. . See the preceding note, relating to top and bottom. in the man through whom the fire passes

that electricity is neither increased nor diini- ! ed through the hook, will be discharged nished.

through the hook; the bottle charged through EXPERIMENT XI.

the coating, will be discharged through the

coating, and not otherways; for the fire must The passing of the electrical fire from the

come out the same way it went in. upper to the lower part * of the bottle, to re

5. To prove this, take two bottles that store the equilibrium, is rendered strongly visible by the following pretty experiment.

were equally charged through the hooks, one • Take a book whose covering is filletted with

in each hand; bring their hooks near each gold; bend a wire of eight or ten inches long,

other, and no spark or shock will follow; be

{ cause each hook is disposed to give fire, and in the form of (m) Fig. 5; slip it on the end

neither to receive it. Set one of the bottles of the cover of the book, over the gold line,

down on glass, take it up by the hook, and so as that the shoulder of it may press upon one end of the gold line, the ring up, but lean

pou apply its coating to the hook of the other ;

To then there will be an explosion and shock, and ing towards the other end of the book. Lay |

ay both bottles will be discharged. the book on a glass or wax,t and on the other

16. Vary the experiment, by charging two end of the gold lines set the bottle electrised: 1. then bend the springing wire, by pressing it

| phials equally, one through the hook, the with a stick of wax till its ring approaches

other through the coating: hold that by the

coating which was charged through the hook, the ring of the bottle wire, instantly there is

and that by the hook which was charged a strong spark and stroke, and the whole line

through the coating: apply the hook of the of gold, which completes the communication,

first to the coating of the other, and there between the top and bottom of the bottle, will

will be no shock or spark. Set that down on appear a vivid fame, like the sharpest lightning. The closer the contact between the

glass which you held by the hook, take it up shoulder of the wire, and the gold at one end

by the coating, and bring the two hooks toge

ther: a spark and shock will follow, and both of the line, and between the bottom of the bot

I phials be discharged. tle and the gold at the other end, the better

In this experiment the bottles are totally the experiment succeeds. The room should

| discharged, or the equilibrium within them

i be darkened. If you would have the whole

restored. The abounding of fire in one of the filletting round the cover appear in fire at

hooks (or rather in the internal surface of one once, let the bottle and wire touch the gold

bottle) being exactly equal to the wanting of in the diagonally opposite corners.

the other; and therefore as each bottle has in B. FRANKLIN.

itself the abounding as well as the wanting, the wanting and abounding must be equal in

each bottle. See 8 8, 9, 10, 11. But if a man To Peter Collinson, London.

holds in his hands two bottles, one fully elecFarther Experiments, confirming the preceding trified, the other not at all, and brings their

Observations.--Leyden Bottle analysed.-Elec- hooks together, he hos but half a shock, and trical Battery.-- Magical Picture. - Electrical the bottles will both remain half electrified, Wheel or Jack.-Electrical Feast.

the one being half discharged, and the other . PAILADELPHIA, 1748. half charged. 1. THERE will be the same explosion and 7. Place two phials equally charged on a shock if the electrified phial is held in one table at five or six inches distance. Let a hand by the hook, and the coating touched cork-ball, suspended by a silk thread, hang with the other, as when held by the coating, between them. If the phials were both chargand touched at the hook.

ed through their hooks, the cork, when it has 2. To take the charged phial safely by the been attracted and repelled by the one, will hook, and not at the same time diminish its not be attracted, but equally repelled by the force, it must first be set down on an electric other. But if the phials were charged, the per se.

one through the hook, and the other* through 3. The phial will be electrified as strongly, the coating, the ball, when it is repelled from if held by the hook, and the coating applied one hook, will be as strongly attracted by to the globe or tube; as when held by the coat- the other, and play vigorously between them, ing, and the hook appliedt.

fetching the electric fluid from the one, and 4. But the direction of the electrical fire delivering it to the other, till both phials are being different in the charging, will also be nearly discharged. different in the explosion. The bottle charg- 8. When we use the terms of charging

* i. e. From the inside to the outside.

* To charge a bottle commodiously through the coat. Placing the book on glass or wax is not necessary to ing, place it on a glass stand; form a communication produce the appearance; it is only to show that the vi. from the prime conductor to the coating, and another sible electricity is not brought up from the common from the hook to the wall or floor. When it is charged, Stock in the earth.

remove the latter communication before you take hold 1 This was a discovery of the very ingenious Mr. of the bottle, otherwise great part of the fire will es. Kinnersley, and by him communicated to me.

cape by it. VOL. II. ...21

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