3. (Mining)
Defn: See Slime, 4. Sludge hole, the hand-hole, or manhole, in a steam boiler, by means of which sediment can be removed.
SLUDGE ACID
Sludge acid.
Defn: Impure dark-colored sulphuric acid that has been used in the refining of petroleum.
SLUDGER
Slud"ger, n.
Defn: A bucket for removing mud from a bored hole; a sand pump.
SLUDGER
Sludg"er, n.
Defn: A shovel for sludging out drains, etc.
SLUDY
Slud"y, a.
Defn: Miry; slushy.