The electron, its isolation and measurement and the determination of some of its properties

by Robert Andrews Millikan

-Particles Shooting through Air

Fig. 16—Photographs of the Tracks of

-Particles Shooting through Air

Fig. 17—Photographs of the Tracks of

-Particles Shooting through Air

Since we know the size of a molecule and the number of molecules per cubic centimeter, we can compute, as in the case of the