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with it; but no such effect followed, nor could I perceive the least difference in the smell of the electric effluvia thus collected, from what it has when collected otherwise, nor does it otherwise affect the body of a person electrized. I likewise put into a phial, instead of water, a strong purgative liquid, and then charged the phial, and took repeated shocks from it, in which case every particle of the electrical fluid must, before it went through my body, have first gone through the liquid when the phial is charging, and returned through it when discharging, yet no other effect followed than if it had been charged with water. I have also smelled the electric fire when drawn through gold, silver, copper, lead, iron, wood, and the human body, and could perceive no difference; the odor is always the same, where the spark does not burn what it strikes; and therefore I imagine it does not take that smell from any quality of the bodies it passes through. And indeed, as that smell so readily leaves the electric matter, and adheres to the knuckle receiving the sparks, and to other things, I suspect that it never was connected with it, but arises instantaneously from something in the air acted upon by it. For, if it was fine enough to come with the electric fluid through the body of one person, why should it stop on the skin of another?

But I shall never have done, if I tell you all my conjectures, thoughts, and imaginations on the nature and operations of this electric fluid, and relate the variety of little experiments we have tried. I have already made this paper too long, for which I must crave pardon, not having now time to abridge it. I shall only add, that, as it has been observed here that spirits will fire by the electric spark in the summer-time, without heating them, when Fahrenheit's thermometer is above seventy; so, when colder, if the operator puts a small flat bottle of spirits in his bosom, or a close pocket, with the spoon, some little time before he uses them, the heat of his body will communicate warmth more than sufficient for the purpose.

ADDITIONAL EXPERIMENTS J

Proving that the Leyden Bottle has no more Electrical Fire in it when charged, than before; nor less when discharged; that, in discharging, the Fire does not issue from the Wire and the Coating at the same 'time, as some have thought, but that the Coating always receives what is discharged by the Wire, or an equal Quantity; the outer Surface being always in a Negative State of Electricity, when the inner Surface is in a Positive State.

Place a thick plate of glass under the rubbing cushion, to cut off the communication of electrical fire from the floor to the cushion; then, if there be no fine points or hairy threads sticking out from the cushion, or from the parts of the machine opposite to the cushion, (of which you must be careful,) you can get but a few sparks from the prime conductor, which are all the cushion will part with. ,

Hang a phial then on the prime conductor, and it will not charge, though you hold it by the coating. But,

Form a communication by a chain from the coating to the cushion, and the phial will charge.

For the globe then draws the electric fire out of the outside surface of the phial, and forces it through the prime conductor and wire of the phial into the inside surface.

VOL. V. V

Thus the bottle is charged with its own fire, no other being to be had while the glass plate is under the cushion.

Hang two cork balls by flaxen threads to the prime conductor; then touch the coating of the bottle, and they will be electrified and recede from each other.

For, just as much fire as you give the coating, so much is discharged through the wire upon the prime conductor, whence the cork balls receive an electrical atmosphere. But,

Take a wire bent in the form of a C, with a stick of wax fixed to the outside of the curve, to hold it by; and apply one end of this wire to the coating, and the other at the same time to the prime conductor, the phial will be discharged; and, if the balls are not electrified before the discharge, neither will they appear to be so after the discharge, for they will not repel each other.

If the phial really exploded at both ends, and discharged fire from both coating and wire, the balls would be more electrified, and recede farther; for none of the fire can escape, the wax handle preventing.

But if the fire with which the inside surface is surcharged, be so much precisely as is wanted by the outside surface, it will pass round through the wire fixed to the wax handle, restore the equilibrium in the glass, and make no alteration in the state of the prime conductor.

Accordingly we find, that, if the prime conductor be electrified, and the cork balls in a state of repellency before-the bottle is discharged, they continue so afterwards. If not, they are not electrified by that discharge.

TO JAMES BOWDOIN,* AT BOSTON.

Enclosing Papers on Electricity.

Philadelphia, 25 October, 1750.

Sir, Enclosed with this I send you all my electrical papers, fairly transcribed, and I have, as you desired, examined the copy and find it correct. I shall be glad to have your observations on them; and, if in any part I have not made myself well understood, I will, on notice, endeavour to explain the obscure passages by letter. My compliments to Mr. Cooper, and the other gentlemen, who were with you here. I hope you all got safe home. I am, Sir,

Your most humble servant,

B. Franklin.

TO A FRIEND IN BOSTON.f

Account of an Occident while making an Electrical Experiment.

Philadelphia, 25 December, 1750.

I have lately made an experiment in electricity, that I desire never to repeat . Two nights ago, being about to kill a turkey by the shock from two large glass jars, containing as much electrical fire as forty common phials, I inadvertently took the whole through my own arms and body, by receiving the fire from the united top wires with one hand, while the other held a chain connected with the outsides of both jars. The company present (whose talking to me, and to one another, I suppose occasioned my inattention to what I was about) say, that the flash was very great, and the crack as loud as a pistol; yet, my senses being instantly gone, I neither saw the one nor heard the other; nor did I feel the stroke on my hand, though I afterwards found it raised a round swelling where the fire entered, as big as half a pistol-bullet; by which you may judge of the quickness of the electrical fire, which by this instance seems to be greater than that of sound, light, or animal sensation.

• Mr. Bowdoin was at this time twenty-three years old. He became distinguished afterwards as a philosopher and statesman, being one of the principal founders and the first president of the American Academy of Arts and Sciences. He took an active and prominent part in the events of the American Revolution, and was subsequently governor of Massachusetts. — Editor.

f A copy of this letter was found among Governor Bowdoin's papers, without the name of the person to whom it was addressed. — Editor.

What I can remember of the matter is, that I was about to try whether the bottles or jars were fully charged, by the strength and length of the stream issuing to my hand, as I commonly used to do, and which I might safely enough have done if I had not held the chain in the other hand. I then felt what I know not how" well to describe; a universal blow throughout my whole body from head to foot, which seemed within as well as without; after which the first thing I took notice of was a violent quick shaking of my body, which gradually remitting, my sense as gradually returned, and then I thought the bottles must be discharged, but could not conceive how, till at last I perceived the chain in my hand, and recollected what I had been about to do. That part of my hand and fingers, which held the chain, was left white, as though the blood had been driven out, and remained so eight or ten minutes after, feeling like dead flesh; and I had a numbness in my arms and the back of my neck,

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