In the publications from the early part of the twentieth century we can find easy to follow teachings of the discoveries which led to the wonders of that modern day period, such as electricity and the telegraph.
Apparently it was Benjamin Franklin who had the first electrical invention of practical use. Or at least this was what was published in 1910.
In Franklin's own time, which was 1706–1790, there was great interest in electricity due to the strange discovery of the Leyden jar. Ben himself explored and experimented with electricity by way of the discovery of Musschenbroek.
The time period of discovery is 1746 and German professor Pieter van Musschenbroek,
a Dutch scientist of the University of Leyden, had tried a new experiment. Later he called it a terrible experiment. It is said that he had used two silk threads to suspend a gun-barrel "which received electricity from an electrical machine." Attached to one end of the gun-barrel hung a brass wire and the lower end of this wire was dipped in a jar of water. In one hand the professor held the jar and with the other he tried to draw sparks from the electrified gun barrel. And so he did!
Apparently what he got was a big shock which is reported to have seemed to him like a lightning strike. He did live to tell the story and told that so violent was the shock that he thought at that moment that it would end his life.
So, don't try this at home- as the disclaimer goes.
Out of this experiment came the Leyden jar. Over a hundred years would pass before a practical use for this jar would actually come into play. But it proved to keep the scientific curiousity flowing and for some the entertainment aspect kept growing.
We would, in our modern time, call the Leyden jar a *capacitor which is a device used to store an electric charge by way of *conductors separated by an insulator. In simple terms we can see it as a battery- see Explore More links at the end for more info
By 1910 the Leyden jar invention of Musschenbroek was recorded into history as the science which eventually formed an important part of wireless telegraph equipment.
The Leyden jar is simply a glass bottle or jar coated with tin foil inside and outside. When charged with electricity the jar will hold its charge until the two coatings are connected by a metal wire or another good conductor of electricity.
More and more people would become interested in electricity by way of this discovery made by Pieter van Musschenbroek.
What was called the friction electrical machine and also the Leyden jar were both fairly easy to make. Fashionable people of the day found these interesting and amusing, especially because of the shock that one could get to the body as the discharge from the "wonderful bottle" let go. And the fact that several people
could receive the shock at the same time was an even greater form of entertainment.
There is even a story of the Abbé Nollet discharging a Leyden jar through a line of monks standing together at the Carthusian Monastery in Paris. The mile long line of solemn monks all jumping into the air caused a show said to be ridiculous in the extreme. I guess this was the Parisian form of play of the late 1700's.
Other great electrical discoveries were also being made in this era. In the period around 1706, a physicist Stephen Gray discovered that some objects conduct electricity and others do not. He found that when a glass tube is electrified by rubbing, it will attract and repel light objects. It was clear electricity could be transferred from one object to another. Gray took it further showing that contact is not necessary, that a "hempen thread" or a wire will carry an electric charge from one object to an
other. But a silk thread will not carry the electric charge.
Gray established
"Some things convey electricity and some do not, and those which do not can be used to prevent the electricity escaping from those which do."
Perhaps he was imagining in his day what would later be a modern telegraph line with the glass insulators on the poles, which prevent the electric
current escaping from the telegraph wire. He set up a line of hempen thread six hundred and fifty feet long, and with an electrical machine at one end of the line electrified a boy suspended from the other end. His own writing on the experiment is recorded here.
A Frenchman, Charles François de Cisternay DuFay, while carrying further the experiments of Gray concluded that there are two kinds of electricity, which he named "vitreous" and "resinous".
Benjamin Franklin would later call these two kinds of electric charge "positive" and "negative."
Franklin made a battery of Leyden jars by connecting the
inner coating and outer coating of a series of jars. By increasing the number of jars he was able to get a much stronger spark than with just a single jar. He too is said to have nearly lost his life by these shocking leyden jars.
