HOPPER n.
A vessel for carrying waste, garbage, etc., out to sea, so constructed as to discharge its load by a mechanical contrivance; -- called also dumping scow. Bell and hopper (Metal.), the apparatus at the top of a blast furnace, through which the charge is introduced, while the gases are retained. -- Hopper boy, a rake in…
HYDROMETER n.
An instrument, variously constructed, used for measuring the velocity or discharge of water, as in rivers, from reservoirs, etc., and called by various specific names according to its construction or use, as tachometer, rheometer, hydrometer, pendulum, etc.; a current gauge.