SUMP, in Mining, denotes a pit sunk down in the bottom of the mine, to cut or prove the lode still deeper than before; and in order to slope and dig it away if necessary, and also to drive on the lode in depth. The sump principally serves as a basin or reservoir, to collect
VOL. XX. Part I.
the water of a mine together, that it may be cleaned out by an engine or machine.