Definition:Electron/Historical Note/Mistake

Source Work

 * Chapter $\text {I}$: Preliminary Survey
 * $\S 1$. Electrostatics
 * $\S 1$. Electrostatics

Mistake

 * The smallest electric charge which it is possible to obtain is that of the ordinary electron, discovered and measured for the first time by in $1897$.

Correction
Technically speaking, did not measure the electric charge on the electron.

Instead he measured the Electron Charge to Mass Ratio.

The actual electric charge on the electron was measured by and  in $1909$.