360The 1740s: electricity in a jar and the Celsius scale
In the 1740s, Anders Celsius proposed the temperature scale now used across most of the world. Scientists learned to store electricity in the Leyden jar, and Benjamin Franklin began his famous experiments. Montesquieu's ideas on separating government powers shaped future constitutions.
In 1742, the Swedish astronomer Anders Celsius proposed a temperature scale based on the freezing and boiling points of water, divided into 100 degrees. His original version ran backwards, with 100 for freezing. It was soon reversed, and the Celsius scale is now standard in science and in most countries.
Electricity fascinated the public. Around 1745 and 1746, experimenters in Germany and in Leiden, in the Netherlands, discovered they could store an electric charge in a glass jar lined with metal. The 'Leyden jar' was the first capacitor and made new experiments possible.
In Philadelphia, Benjamin Franklin began studying electricity in the late 1740s. He introduced terms still used today, such as positive, negative and battery.
In 1748, the French writer Montesquieu published The Spirit of the Laws. He argued that liberty is best protected when the powers to make laws, carry them out and judge them are held by separate branches. The idea later shaped the constitution of the United States and many others.
Much of Europe fought the War of the Austrian Succession from 1740 to 1748, which ended with the Treaty of Aix-la-Chapelle.
- 1742
- Celsius proposes his temperature scale
- 1745–46
- The Leyden jar is invented
- 1748
- Montesquieu's The Spirit of the Laws
- 1748
- War of the Austrian Succession ends
Sources: Britannica · Franklin Institute · Uppsala University.