The Electric Explosion

Take a card, a quire of paper, or the cover of a book; and keep it

close to the outside coating of a charged jar: put one knob of the

discharging-rod upon the card, quire of paper, &c., so that, between

the knob and coating of the jar, the thickness of that card or quire

of paper only is interposed; lastly, by bringing the other knob of the

discharged rod near the knob of the jar, make the discharge, and the

electric s ark will pierce a hole (or perhaps several) quite through

the card or quire of paper. This hole has a bur raised on each side,

except the card, &c., be pressed hard between the discharging-rod and

the jar. If this experiment be made with two cards instead of one,

which, however, must be kept very little distant from one another,

each of the cards, after the explosion, will be found pierced with one

or more holes, and each hole will have burs on both surfaces of each

card. The hole, or holes, are larger or smaller, according as the

card, &c., is more damp or more dry. It is remarkable, that if the

nostrils are presented to it, they will be affected with a sulphurous,

or rather a phosphoric smell, just like that produced by an excited

electric.



If, instead of paper, a very thin plate of glass, resin, sealing-wax,

or the like, be interposed between the knob of the discharging-rod and

the outside coating of the jar, on making the discharge, this will be

broken in several pieces.