A History of Science-2 [107]
Two more great discoveries, galvanism and electro-magnetic induction, were necessary before the practical motor became possible. The sober Gordon had a taste for the spectacular almost equal to that of Bose. It was he who ignited a bowl of alcohol by turning a stream of electrified water upon it, thus presenting the seeming paradox of fire produced by a stream of water. Gordon also demonstrated the power of the electrical discharge by killing small birds and animals at a distance of two hundred ells, the electricity being conveyed that 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, be 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 the common way. When I present this phial and nail to a tin tube, which I have, fifteen feet long, nothing but experience can make a person believe how strongly it is electrified. I am persuaded," he adds, "that in this manner Mr. Bose would not have taken a second electrical kiss. Two thin glasses have been broken by the shock of it. It appears to me very extraordinary, that when this phial and nail are in contact with either conducting or non-conducting matter, the strong shock does not follow. I have cemented it to wood, metal, glass, sealing-wax, etc., when I have electrified without any great effect. The human body, therefore, must contribute something to it. This opinion is confirmed by my observing that unless I hold the phial in my hand I cannot fire spirits of wine with it."[2] But it seems that none of the men who saw this account were able to repeat the experiment and produce the effects claimed by Von Kleist, and probably for this reason the discovery of the obscure Pomeranian was for a time lost sight of. Musschenbroek's discovery was made within a short time after Von Kleist's--in
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, be 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 the common way. When I present this phial and nail to a tin tube, which I have, fifteen feet long, nothing but experience can make a person believe how strongly it is electrified. I am persuaded," he adds, "that in this manner Mr. Bose would not have taken a second electrical kiss. Two thin glasses have been broken by the shock of it. It appears to me very extraordinary, that when this phial and nail are in contact with either conducting or non-conducting matter, the strong shock does not follow. I have cemented it to wood, metal, glass, sealing-wax, etc., when I have electrified without any great effect. The human body, therefore, must contribute something to it. This opinion is confirmed by my observing that unless I hold the phial in my hand I cannot fire spirits of wine with it."[2] But it seems that none of the men who saw this account were able to repeat the experiment and produce the effects claimed by Von Kleist, and probably for this reason the discovery of the obscure Pomeranian was for a time lost sight of. Musschenbroek's discovery was made within a short time after Von Kleist's--in