hat distance through
small wires.

THE LEYDEN JAR DISCOVERED

As yet no one had discovered that electricity could be stored, or
generated in any way other than by some friction device. But very soon
two experimenters, Dean von Kleist, of Camin, Pomerania, and Pieter van
Musschenbroek, the famous teacher of Leyden, apparently independently,
made the discovery of what has been known ever since as the Leyden
jar. And although Musschenbroek is sometimes credited with being the
discoverer, there can be no doubt that Von Kleist's discovery antedated
his by a few months at least.

Von Kleist found that by a device made of a narrow-necked bottle
containing alcohol or mercury, into which an iron nail was inserted, he
was able to retain the charge of electricity, after electrifying this
apparatus with the frictional machine. He made also a similar device,
more closely resembling the modern Leyden jar, from a thermometer tube
partly filled with water and a wire tipped with a ball of lead. With
these devices he found that he could retain the charge of
electricity for several hours, and could produce the usual electrical
manifestations, even to igniting spirits, quite as well as with the
frictional machine. These experiments were first made in October,
1745, and after a month of further experimenting, Von Kleist sent the
following account of them to several of the leading scientists, among
others, Dr. Lieberkuhn, in Berlin, and Dr. Kruger, of Halle.

"When a nail, or a piece of thick brass wire, is put into a small
apothecary's phial and electrified, remarkable effects follow; but the
phial must be very dry, or warm. I commonly rub it over beforehand with
a finger on which I put some pounded chalk. If a little mercury or a few
drops of spirit of wine be put into it, the experiment succeeds better.
As soon as this phial and nail are removed from the electrifying-glass,
or the prime conductor, to which it has been exposed, is taken away, it
throws out a pencil of flame so long that, with this burning machine in
my hand, I have taken above sixty steps in walking about my room. When
it is electrified strongly, I can take it into another room and there
fire spirits of wine with it. If while it is electrifying I put my
finger, or a piece of gold which I hold in my hand, to the nail, I
receive a shock which stuns my arms and shoulders.

"A tin tube, or a man, placed upon electrics, is electrified much
stronger by this means than in