Place a nicely-adjusted pair of forceps at the top of the receiver,
communicating with the top of the outside through a hole, so that they
may be opened by the fingers. Then place on each of the little plates
a _sovereign_ and a _feather_. Exhaust the air from the receiver: and
having done so, detach the objects, so that they may fall. In the open
air the sovereign will fall long before the feather, but in vacuo, as
in the receiver now exhausted of its air, they will fall both together,
and reach the bottom of the glass at the same instant.