BENJAMIN FRANKLIN 'jz 



is the same in both cases, it consisting in the different proportion 

 of electricity in the electrified body, and that common mass. But 

 the force, with which the electrified body retains its atmosphere by 

 attracting it, is proportioned to the surface over which the particles 

 are placed ; that is, four square inches of that surface retain their 

 atmosphere with four times the force that one square inch retains 

 its atmosphere. And, as in plucking the hairs from the horse's 

 tail, a degree of strength not sufficient to pull away a handful at 

 once, could yet easily strip it hair by hair, so a blunt body presented 

 cannot draw off a number of particles at once, but a pointed one, 

 with no greater force, takes them away easily, particle by particle. 



These explanations of the power and operation of points, when they 

 first occurred to me, and while they first floated in my mind, appeared 

 perfectly satisfactory ; but now I have written them, and considered 

 them more closely, I must own I have some doubts about them ; yet, as 

 I have at present nothing better to offer in their stead, I do not cross 

 them out ; for, even a bad solution read, and its faults discovered, has 

 often given rise to a good one, in the mind of an ingenious reader. 



Nor is it of much importance to us to know the manner in which 

 nature executes her laws ; it is enough if we know the laws themselves. 

 It is of real use to know that China left in the air unsupported, will fall 

 and break ; but how it comes to fall, and why it breaks, are matters of 

 speculation. It is a pleasure indeed to know them, but we can pre- 

 serve our China without it. 



Thus, in the present case, to know this power of points may pos- 

 sibly be of some use to mankind, though we should never be able to 

 explain it. The following experiments, as well as those in my first 

 paper, show this power. I have a large prime conductor, made of 

 several thin sheets of clothier's pasteboard, formed into a tube, near 

 ten feet long and a foot diameter. It is covered with Dutch embossed 

 paper, almost totally gilt. This large metallic surface supports a 

 much greater electrical atmosphere than a rod of iron of fifty times 

 the weight would do. It is suspended by silk lines, and when charged 

 will strike, at near two inches distance, a pretty hard stroke, so as 

 to make one's knuckles ache. Let a person standing on the floor 

 present the point of a needle, at twelve or more inches distance from 

 it, and while the needle is so presented, the conductor cannot be 

 charged, the point drawing off the fire as fast as it is thrown on by the 



