Surely the ability to get a number for e is important in the Millikan oil
drop experiment! There are "easier" experiments for measuring e/m, h/e,
etc., but this is one where you are able to measure one of the fundamental
constants all by itself--you then obtain values for the others.
Martha Takats
Physics Department
Ursinus College
Collegeville, PA 19426
mtakats@acad.ursinus.edu