ELECTRICITY TIMELINE

shows that electricity doesn't have to be made in place by rubbing but can also be transferred from place to place with conducting wires. He also shows that the charge on electrified objects resides on their surfaces.
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discovers that electricity comes in two kinds which he called resinous(-) and vitreous(+).
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discovered that electricity was controllable.
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He invented the theory of one-fluid electricity in which one of Nollet's fluids exists and the other is just the absence of the first. He proposed. the principle of conservation of charge and calls the fluid that exists and flows ``positive''. He also discovers that electricity can act at a distance in situations where fluid flow makes no sense.
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invents the two-fluid theory electricity.

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Sulzer puts lead and silver together in his mouth, performing the first recorded ``tongue test'' of a battery.
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discovers the divergence theorem in connection with the study of gravitation. It later becomes known as Gauss's law
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acting on a suggestion in a letter from Benjamin Franklin, he showed that hollow charged vessels contain no charge on the inside and based on his knowledge that hollow shells of mass have no gravity inside correctly thinking that the electric force law is inverse square.
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uses a torsion balance to verify that the electric force law is inverse square. He also proposes a combined fluid/action-at-a-distance theory like that of Aepinus but with two conducting fluids instead of one. He also discovers that the electric force near a conductor is proportional to its surface charge density and makes contributions to the two-fluid theory of magnetism.
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demonstrated what we now understand to be the electrical basis of nerve impulses when he made frog muscles twitch by jolting them with a spark from an electrostatic machine.
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