1750 - 1774

With his famous kite experiment and other forays into science, Benjamin Franklin advances knowledge of electricity, inspiring his English friend Joseph Priestley to do the same.


Steel magnets

John Michell, an English geologist, publishes A Treatise on Artificial Magnets, which describes how to make strong steel magnets and gives an account of his discovery of the inverse-square law for the attractive and repulsive forces of magnets.

Aurora borealis

Perh Vilhelm Margentin writes a letter to the Swedish Academy of Sciences in which he comments on the effect of the aurora borealis on a magnetized needle.

Franklin's electricity

Leyden JarBenjamin Franklin's letters to a colleague are published as Experiments and Observations on Electricity. The work includes Franklin’s views on positive and negative charges, the use of pointed conductors, improvements to the Leyden jar and a detailed plan for his famous kite experiment.

Kite experiment

Leyden JarThe connection between lightning and electricity is proven when Benjamin Franklin’s plan to collect the charge from a storm cloud into a Leyden jar with a key attached to a kite is successfully completed.

Mathematical magnets

Franz Aepinus, a German natural philosopher, publishes his Tentamen Theoriae Electricitatis et Magnetismi (“An Attempt at a Theory of Electricity and Magnetism”), the first book to consider electricity and magnetism in terms of mathematics.

Tongue tests

VoltaJohann Sulzer, a Swiss physicist living in Berlin, conceives and carries out an experiment that involves placing two dissimilar metals in his mouth so that they touch one another, producing a strange sensation in the tongue. This was essentially the first tongue test of a battery, and was repeated by many other scientists, including Alessandro Volta.


Leyden JarSwedish physicist Johannes Wilcke invents a simple apparatus for producing substantial amounts of electric charge, which would later come to be known as the electrophorus.

Law of force

Joseph Priestley, an English pastor and science enthusiast, deduces that the law of force between electric charges must be the same as Newton’s inverse-square law for gravitational force. His History and Present State of Electricity is released, in which all data available in the field at the time is reviewed.

Magnetic inclination

Johannes Wilcke compiles and publishes the first magnetic inclination chart that includes measurements from around the globe.

Steam condensing engine

Steam EngineScottish inventor James Watt contrives the steam condensing engine, a design he improves over the next two decades. The machine is used late in the following century for large-scale electricity generation.
More in this category: « 1700 - 1749 1775 - 1799 »
National Maglab Logo

Magnet Academy is a free resource on magnetism & electricity brought to you by the Center for Integrating Research + Learning at the National High Magnetic Field Laboratory.