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the cushion again, the outer surface delivers , but moving on the approach of the rubbed tube, its overplus fire into the cushion, the opposite is explained. When an additional quantity inner surface receiving at the same time an of the electrical fluid is applied to the side of equal quantity from the floor. Every electri- the vessel by the atmosphere of the tube, a cian knows that a globe wet within will afford quantity is repelled and driven out of the inlittle or no fire, but the reason has not before ner surface of that side into the vessel, and been attempted to be given, that I know of. there affects the feather, returning again into
34. So if a tube lined with a non-electric its pores, when the tube with its atmosphere be rubbed* little or no fire is obtained from is withdrawn; not that the particles of that it; what is collected from the hand, in the atmosphere did themselves pass through the downward rubbing stroke, entering the pores glass to the feather. And every other apof the glass, and driving an equal quantity out pearance I have yet seen, in which glass and of the inner surface into the non-electric lin-electricity are concerned, are, I think, exing: and the hand in passing up to take a plained with equal ease by the same hypothesecond stroke, takes out again what had been sis. Yet, perhaps, it may not be a true one, thrown into the outer surface, and then the and I shall be obliged to him that affords me inner surface receives back again what it had a better. given to the non-electric lining. Thus the 35. Thus I take the difference between nonparticles of electral fluid belonging to the in- electrics, and glass, an electric per se, to conside surface go in and out of their pores every sist in these two particulars. Ist, That a nonstroke given to the tube. Put a wire into the electric easily suffers a change in the quantube, the inward end in contact with the non- tity of the electric fluid it contains. You electric lining, so it will represent the Ley- may lessen its whole quantity, by drawing den bottle. Let a second person touch the out a spark, which the whole body will again wire, while you rub, and the fire driven out resume: but of glass you can only lessen the of the inward surface when you give the quantity contained in one of its surfaces; and stroke, will pass through him into the common not that, but by supplying an equal quantity mass, and return through him when the inner at the same time to the other surface: so that surface resumes its quantity, and therefore the whole glass may always have the same this new kind of Leyden bottle cannot be so quantity in the two surfaces, their two difcharged. But thus it may: after every stroke, ferent quantities being added together. And before you pass your hand up to make another, this can only be done in glass that is thin; belet a second person apply his finger to the yond a certain thickness we have yet no wire, take the spark, and then withdraw his power that can make this change. And, finger; and so on till he has drawn a number 2dly, that the electric fire freely removes of sparks; thus will the inner surface be ex- from place to place, in and through the subhausted, and the outer surface charged; then stance of a non-electric, but not so through the wrap a sheet of gilt paper close round the substance of glass. If you offer a quantity to outer surface, and grasping it in your hand one end of a long rod of metal, it receives it, you may receive a shock by applying the and when it enters, every particle that was finger of the other hand to the wire : for now before in the rod pushes its neighbour quite to the vacant pores in the inner surface resume the further end, where the overplus is distheir quantity, and the overcharged pores in charged ; and this instantaneously where the the outer surface discharge that overplus; the rod is part of the circle in the experiment of equilibrium being restored through your body, the shock. But glass, from the smallness of which could not be restored through the glass.t its pores, or stronger attraction of what it conIf the tube be exhausted of air, a non-electric tains, refuses to admit so free a motion: a lining, in contact with the wire, is not neces- glass rod will not conduct a shock, nor will sary, for in vacuo the electrical fire will fly the thinnest glass suffer any particle entering freely from the inner surface, without a non- one of its surfaces to pass through to the electric conductor ; but air resists in motion; other. for being itself an electric per se, it does not
36. Hence we see the impossibility of sucattract it, having already its quantity. So the cess in the experiments proposed, to draw out air never draws off an electric atmosphere the effluvial virtues of a non-electric, as cinfrom any body, but in proportion to the non- namon, for instance, and mixing them with electrics mixed with it: it rather keeps such the electric fluid, to convey them with that inan atmosphere confined, which, from the mu- to the body, by including it in the globe, and tual repulsion of its particles, tends to dissipa- then applying friction, &c. For though the tion, and would immediately dissipate in va- effluvia of cinnamon, and the electric fluid cuo. And thus the experiment of the feather should mix within the globe, they would enclosed in a glass vessel hermetically sealed, never come out together through the pores of *Gilt paper, with the gilt face next the glass, does for the electric fluid itself cannot come
the glass, and so go to the prime conductor, † See Farther Experiments, sect. 15.
through; and the prime conductor is always VOL. II. ... 2 L
supplied from the cushion, and that from the one person, why should it stop on the skin of floor. And besides, when the globe is filled another? with cinnamon, or other non-electric, non But I shall never have done, if I tell you electric fluid can be obtained from its outer all my conjectures, thoughts, and imaginations surface, for the reason before-mentioned. I on the nature and operations of this electric have tried another way, which I thought more fluid, and relate the variety of little experilikely to obtain a mixture of the electric and ments we have tried. I have already made other effluvia together, if such a mixture had this paper too long, for which I must crave been possible. I placed a glass plate under pardon, not having now time to abridge it. my cushion, to cut off the communication be- I shall only add, that as it has been observed tween the cushion and floor ; then brought a here that spirits will fire by the electric spark small chain from the cushion into a glass of in the summer time, without heating them, oil of turpentine, and carried another chain when Fahrenheit's thermometer is above 70; from the oil of turpentine to the floor, taking so when colder, if the operator puts a small care that the chain from the cushion to flat bottle of spirits in his bosom, or a close the glass, touched no part of the frarne of the pocket, with the spoon, some little time bemachine. Another chain was fixed to the fore he uses them, the heat of his body will priine conductor, and held in the hand of a communicate warmth more than sufficient for person to be electrified. The ends of the two the purpose. chains in the glass were near an inch distant from each other, the oil of turpentine between.--Now the globe being turned could draw no fire from the floor through the ma
Additional Experiments : chine, communication that way being cut off Proving that the Leyden Bottle has no more by the thick glass plate under the cushion: electrical fire in it when charged, than before : it must then draw it through the chains
nor less when discharged: that, in discharging,
the Fire does not issue from the Wire and the whose ends were dipped in the oil of turpen
Coating at the same time, as some have tine. And as the oil of turpentine, being an
thought, but that the Coating always receires electric per se, would not conduct, what what is discharged by the Wire, or an equal came up from the floor was obliged to jump quantity; the other Surface being always in from the end of one chain to the end of the a negative state of Electricity, when the inner other, through the substance of that oil, which Surface is in a positive state. we could see in large sparks, and so it had a PLACE a thick plate of glass under the rubfair opportunity of seizing some of the finest bing cushion, to cut off the communication of particles of the oil in its passage, and carry- electrical fire from the floor to the cushion, ing them off with it: but no such effect fol- then if there be no fine points or hairy threads lowed, nor could I perceive the least differ- sticking out from the cushion, (of which you ence in the smell of the electric effluvia thus must be careful) you can get but a few sparks collected, from what it has when collected from the prime conductor, which are all the otherwise, nor does it otherwise affect the body cushion will part with. of a person electrised. I likewise put into a Hang a phial then on the prime conductor, phial, instead of water, a strong purgative li- and it will not charge though you hold it by quid, and then charged the phial, and took re- the coating.-- But, peated shocks from it, in which case every Form a communication by a chain from particle of the electrical fluid must, before it the coating to the cushion, and the phial will went through my body, have first gone through charge. the liquid when the phial is charging, and re For the globe then draws the electric fire turned through it when discharging, yet no out of the outside surface of the phial, and other effect followed than if it had been charg- forces it through the prime conductor and ed with water. I have also smelt the elec- wire of the phial into the inside surface. tric fire when drawn through gold, silver, cop Thus the bottle is charged with its own per, lead, iron, wood, and the human body, fire, no other being to be had while the glass and could perceive no difference: the odour plate is under the cushion. is always the same, where the spark does not Hang two cork balls by flaxen threads to burn what it strikes; and therefore I imagine the prime conductor; then touch the coating it does not take that smell from any quality of the bottle, and they will be electrified and of the bodies it passes through. And indeed, recede from each other. as that smell so readily leaves the electric For just as much fire as you give the coatmatter, and adheres to the knuckle receiving ing, so much is discharged through the wire the sparks, and to other things; I suspect that upon the prime conductor, whence the cork it never was connected with it, but arises in- balls receive an electrical atmosphere. But, stantaneously
from something in the air acted Take a wire bent in the form of a C, with upon by it. For if it was fine enough to come a stick of wax fixed to the outside of the with the electric fluid through the body of curve, to hold it by; and apply one end of
this wire to the coating, and the other at the not but take notice of the large comazants (as same time to the prime conductor, the phial he calls them) that settled on the spintles at will be discharged; and if the balls are not the top-mast heads, and burnt like very large electrified before the discharge, neither will torches (before the stroke.) According to my they appear to be so after the discharge, for opinion, the electrical fire was then drawing they will not repel each other.
off, as by points, from the cloud; the largeIf the phial really exploded at both ends, ness of the flame betokening the great quanand discharged fire from both coating and tity of electricity in the cloud: and had there wire, the balls would be more electrified, and been a good wire communication from the spinrecede farther; for none of the fire can es- tle heads to the sea, that could have conducted cape, the wax handle preventing.
more freely than tarred ropes, or mats of turBut if the fire with which the inside sur- pentine wood, I imagine there would either face is surcharged be so much precisely as is have been no stroke, or, if a stroke, the wire wanted by the outside surface, it will pass would have conducted it all into the sea with round through the wire fixed to the wax out damage to the ship. handle, restore the equilibrium in the glass, His compasses lost the virtue of the loadand make no alteration in the state of the stone, or the poles were reversed; the prime conductor.
north point turning to the south.-By elecAccordingly we find, that if the prime con- tricity we have (here at Philadelphia) freductor be electrified, and the cork balls in a quently given polarity to needles, and restate of repellency before the bottle is dis- versed it at pleasure. Mr. Wilson, at Loncharged, they continue so afterwards. If not, don, tried it on too large masses, and with too they are not electrified by that discharge. small force.
A shock from four large glass jars, sent
through a fine sewing-needle, gives it polarTo Peter Collinson, London.
ity, and it will traverse when laid on water. Accumulation of the electrical Fire proved to be -If the needle, when struck, lies east and
in the electrified Glass.-Effect of Lightning west, the end entered by the electric blast on the Needle of Compasses, explained.-Gun-points north.—If it lies north and south, the powder fired by the electric Flame.
end that lay towards the north will continue to PHILADELPHIA, July 27, 1750. MR. Watson, I believe, wrote his Obser- fire entered at that end, or at the contrary end.
point north when placed on water, whether the vations on my last paper in haste, without having first well considered the experiments needle is struck lying north and south, weak
The polarity given is strongest when the related $ 17,* which still appear to me de- est when lying east and west; perhaps if cisive in the question, - Whether the accumu- the force was still greater, the south end, enlation of the electrical fire be in the electri- tered by the fire (when the needle lies north cal glass, or in the non-electric matter con- and south) might become the north, othernected with the glass ? and to demonstrate wise it puzzles us to account for the inverting that it is really in the glass. As to the experiment that ingenious gen- must always be found in that situation, and
of compasses by lightning ; since their needles tleman mentions, and which he thinks cond by our little experiments, whether the blast clusive on the other side, I persuade myself entered the north and went out at the south he will change his opinion of it, when he con- end of the needle, or the contrary, still the siders, that as one person applying the wire end that lay to the north should continue to of the charged bottle to warm spirits, in a
point north. spoon held by another person, both standing on the floor, will fire the spirits, and yet such ales are sometimes finely blued like a watch
In these experiments the ends of the neefiring will not determine whether the accumulation was in the glass or the non-elec spring by the electric flame. This colour tric ; so the placing another person between given by the flash from two jars only, will them, standing on wax, with a bason in his wipe off, but four jars fix it, and frequenthand, into which the water from the phial is have had their heads and points melted off by
ly melt the needles. I send you some that poured, while he at the instant of pouring
our mimic lightning; and a pin that had its presents a finger of his other hand to the spirits, does not at all alter the case; the point melted off, and some part of its head and
Sometimes the surface on the stream from the phial, the side of the bason, body of the needle is also run, and appears with the arms and body of the person on the blistered when examined by a magnifying wax, being all together but as one long wire; glass: the jars I make use of hold seven or reaching from the internal surface of the phial eight gallons, and are coated and lined with to the spirits. June 29, 1751. In capt. Waddell's account of a globe nine inches diameter to charge it.
tin-foil; each of them takes a thousand turns* of the effects of lightning on his ship, I could
* The cushion being afterwards covered with a long * See the paper entitled, Farther Experiments, fĆ. flap of buckskin, which might cling to the globe; and
I send you two specimens of tin-foil melted | may seem to many a little extravagant to between glass, by the force of two jars only. suppose.--So we are not got beyond the skill
I have not heard that any of your European of Rabelais's devils of two years old, who, he electricians have ever been able to fire gun- humourously says, had only learnt to thunder powder by the electric filame. We do it and lighten a little round the head of a cab here in this manner:-A small cartridge is bage.
B. FRANKLIN. filled with dry powder, hard rammed, so as to bruise some of the grains; two pointed wires are then thrust in, one at each end, the Queries and Answers referred to in the forepoints approaching each other in the middle
going Letter. of the cartridge, till within the distance of half an inch; then, the cartridge being placed The terms, electric per se, and non-electric, imin circuit, when the four jars are discharged,
proper.-Ner relation between Metals and
Water.--Effects of Air in electrical Experithe electric flame leaping from the point of
ments.-Experiments for discovering more of one wire to the point of the other, within the
the Qualities of the electric Fluid. cartridge amongst the powder, fires it, and the explosion of the powder is at the same in
Query. WHEREIN consists the difference bestant with the crack of the discharge.
tween an electric and a non-electric body? B. FRANKLIN.
Answer. The terms electric per se, and nonelectric, were first used to distinguish bodies,
ona mistaken supposition that those called elecTo Cadwallader Colden,* at New York, com- trics per se, alone contained electric matter in municated to Mr. Collinson.
their substance, which was capable of being
excited by friction, and of being produced or Unlimited Nature of the Electric Force.
drawn from them, and communicated to those
PAILADELPHIA, 1751. called non-electrics, supposed to be destitute I ENCLOSE YOU answers, such as my present of it: for the glass, &c. being rubbed, discohurry of business will permit me to make, to vered signs of having it, by snapping to the the principal queries contained in yours of finger, attracting, repelling, &c. . and could the 28th instant, and beg leave to refer you communicate those signs to metals and water. to the latter piece in the printed collection of --Afterwards it was found, that rubbing of my papers, for farther explanation of the dif- glass would not produce the electric matter, ference between what is called electrics per unless a communication was preserved bese, and non-electrics. When you have had tween the rubber and the floor; and subsetime to read and consider these papers, I will quent experiments proved that the electric endeavour to make any new experiments you matter was really drawn from those bodies shall propose, that you think may afford far, that at first were thought to have none in ther light or satisfaction to either of us; and them. Then it was doubted whether glass, shall be much obliged to you for such remarks, and other bodies called electrics per se, had objections, &c. as may occur to you.- I for- really any electric matter in them, since they get whether I wrote to you that I have melted apparently afforded none but what they first brass pins and steel needles, inverted the extracted from those which had been called poles of the magnetic needle, given a magne non-electrics. But some of my experiments tism and polarity to needles that had none, show, that glass contains it in great quantity, and fired dry gunpowder by the electric spark. and I now suspect it to be pretty equally difI have five bottles that contain eight or nine fused in all the matter of this terraqueous gallons each, two of which charged are suf- globe. If so, the terms electric per se, and ficient for those purposes; but I can charge non-electric, should be laid aside as improper : and discharge them altogether, There are and (the only difference being this, that some no bounds (but what expense and labour give) bodies will conduct electric matter, and to the force man may raise and use in the others will not) the terms conductor and nonelectrical
for bottle may be added to conductor may supply their place. If any bottle in infinitum, and all united and dis- portion of electric matter is applied to a piece charged together as one, the force and effect of conducting matter, it penetrates and flows proportioned to their number and size. The through it, or spreads equally on its surface; greatest known effects of common lightning if applied to a piece of non-conducting matter, may, I think, without much difficulty, be ex- it will do neither. Perfect conductors of ceeded in this way, which a few years since electric matter are only metals and water. could not have been believed, and even now Other bodies conducting only as they contain
a mixture of those; without more or less of care being taken to keep that flap of a due temperature, which they will not conduct at all.* This between too dry and too mojst, we found so much more of the electric fluid was obtained, as that 150 turns
* This proposition is since found to be too general; * This gentleman was afterwards lieutenant-go Mr. Wilson having discovered that melted wax and
vernor of New York.
rosin will also conduct.
(by the way) shows a new relation between we concluded that the air's elasticity was not metals and water heretofore unknown. affected thereby.
To illustrate this by a comparison, which, however, can only give a faint resemblance. An experiment towards discovering more of Electric matter passes through conductors as
the qualities of the electrical fluid. water passes through a porous stone, or spreads on their surfaces as water spreads on
From the prime conductor, hang a bullet a wet stone; but when applied to non-con- by a wire hook; under the bullet, at half an ductors, it is like water dropt on a greasy inch distance, place a bright piece of silver stone, it neither penetrates, passes through, nor to receive the sparks; then let the wheel be spreads on the surface, but remains in drops turned, and in a few minutes, (if the repeated where it falls. See farther on this head, in sparks continually strike in the same spot) my last printed piece, entitled, Opinions and the silver will receive a blue stain, nearly the Conjectures, &c. 1749.
colour of a watch-spring. Query. What are the effects of air in elec A bright piece of iron will also be spotted, trical experiments ?
but not with that colour; it rather seems Answer. All I have hitherto observed are corroded. these. Moist air receives and conducts the On gold, brass, or tin, I have not perceived electrical matter in proportion to its moisture, it makes any impression. But the spots on quite dry air not at all: air is therefore to be the silver or iron will be the same, whether classed with the non-conductors. Dry air as- the bullet be lead, brass, gold, or silver. sists in confining the electrical atmosphere to
On a silver bullet there will also appear a the body it surrounds, and prevents its dissi- small spot, as well as on the plate below it. pating; for in vacuo it quits easily, and points operate stronger, i. e. they throw off or attract the electrical matter more freely, and Cadwallader Colden, New York. at greater distances; so that air intervening Mistake, that only Metals and Waters were conobstructs its passage from body to body in ductors, rectified.--Supposition of a region of some degree. A clean electrical phial and electric fire above our atmosphere.-Theorem wire, containing air instead of water, will not concerning Light.- Poke-weed a cure for Canbe charged nor give a shock, any more than
cers.-Read at the Royal Society, of London, if it was filled with powder of glass; but ex
Nov. 11, 1756. hausted of air, it operates as well as if filled
PHILADELPHIA, April 23, 1752. with water. Yet an electric atmosphere and
In considering your favour of the 16th past, air do not seem to exclude each other, for we
I recollected my having wrote you answers breathe freely in such an atmosphere, and dry to some queries concerning the difference beair will blow through it without displacing or
tween electrics per se, and non-electrics, and driving it away. I question whether the the effects of air in electrical experiments, strongest dry north-wester * would dissipate which, I apprehend, you may not have re it. I once electrified a large cork-ball at the ceived. The date I have forgotten. end of a silk thread three feet long, the other
We have been used to call those bodies end of which I held in my fingers, and whirl'd electrics per se, which would not conduct the it round, like a sling one hundred times in electric fluid; we once imagined that only the air, with the swiftest motion I could pos- such bodies contained that fluid ; afterwards sibly give it, yet it retained its electric atmas that they had none of it, and only educed it phere, though it must have passed through showed our mistake. It is to be found in all
from other bodies: but further experiments eight hundred yards of air, allowing my arm in giving the motion to add a foot to the semi-matter we know of; and the distinctions of diamater of the circle.—By quite dry air, 1 electrics per se, and non-electrics, should now mean the dryest we have: for perhaps we be dropt as improper, and that of conductors never have any perfectly free from moisture, and non-conductors assumed in its place, as I An electrical atmosphere raised round a thick mentioned in those answers. wire, inserted in a phial of air, drives out none of the air, nor on withdrawing that atmos- red ink in a tea-spoon was applied to the opening of
small part of it out through the syphon. Then a little phere will any rush in, as I have found by a the outer leg of the syphon; so that as the air within curious experimentt accurately made, whence cooled, a little of the ink might rise in that leg. When
the air within the bottle came to be of the same tem
perature of that without, the drop of red ink would * The cold dry wind of North America.
rest in a certain part of the leg. But the warmth of a The experiment here mentioned was thus made. finger applied to the phial would cause that drop to deAn empty phial was stopped with a cork. Through scend, as the least outward coolness applied would the cork passed a thick wire, as usual in the Leyden ex make it ascend. When it had found its situation, and periment, which wire almost reached the bottom. was at rest, the wire was electrified by a communica. Through another part of the cork passed one leg of a tion from the prime conductor. This was supposed to small glass syphon, the other leg on the outside came give an electric atmosphere to the wire within the bot. down almost to the bottom of the phial. This phial tle, which might likewise rarify the included air, and was first held a short time in the hand, which, warm of course depress the drop of ink in the syphon. But no ing, and of course ratifying the air within, drové a such effect followed.