The electron, its isolation and measurement and the determination of some of its properties — John Stuart Mill — John Shaqi
The electron, its isolation and measurement and the determination of some of its properties
John Stuart Mill · en
Their second contention is the same as that originally advanced,
namely, that, in some instances, when is determined with the aid
of Stokes’s Law of fall (equation 12, p. 91), even when Cunningham’s
correction or my own (equation 15, p. 101) is employed, the result
comes out very much lower than . Their third claim
is that the value of , determined as just explained from the
Brownian movements, is in general higher than the value computed from
the law of fall, and that the departures become greater and greater
the smaller the particle. These observers conclude therefore that
we oil-drop observers failed to detect sub-electrons because our
droplets were too big to be able to reveal their existence. The minuter
particles which they study, however, seem to them to bring these
sub-electrons to light. In other words, they think the value of the
smallest charge which can be caught from the air actually is a function
of the radius of the drop on which it is caught, being smaller for
small drops than for large ones.
Ehrenhaft and Zerner even analyze our report on oil droplets and find
that these also show in certain instances indications of sub-electrons,
for they yield in these observers’ hands too low values of ,
whether computed from the Brownian movements or from the law of fall.
[Pg 168]
When the computations are made in the latter way is found,
according to them, to decrease with decreasing radius, as is the case
in their experiments on particles of mercury and gold.
III. CAUSES OF THE DISCREPANCIES