Episode 1 of 1

Publication of the 1811 Memoir

When: 1811
Where: Journal de Physique
Part of: Amedeo Avogadro publishes his memoir on the molecular content of gases

Avogadro published his essay on relative molecular masses in the Journal de Physique, proposing the equality of gas volumes and molecule counts.

The memoir, titled 'Essay on a manner of Determining the Relative Masses of the Elementary Molecules of Bodies,' was submitted to the Journal de Physique, de Chimie et d'Histoire naturelle. It contained the hypothesis that equal volumes of gases at the same temperature and pressure contain the same number of molecules.

Sources

Amedeo Avogadro Wikipedia, revision of 2026-09-03
Avogadro's law Wikipedia, revision of 2026-04-30

Machine-drafted from the cited Wikipedia passages and checked by a reviewing model, not by a human editor. Every passage cites the revision it was written from; dates and places follow those passages.