DESCENDING SMOKE.
THE SOUNDLESS BELL.
Set a bell on the pump-plate, having a contrivance so as to ring it at pleasure, and cover it with a receiver; then make the clapper sound against the bell, and it will be heard to sound very well; now exhaust the receiver of air, and then when the clapper strikes against the sides of the bell the sound can be scarcely heard.
SOUNDLESS BELL.
FLOATING FISH.
SOUNDLESS BELL.