1875 E. H. KnightAmer. Mech. Dict. III. 1847/2Quenching-tub, the vessel in which the heated iron or steel from the forge is plunged, in order to cool or temper it.
1999 Herald Sun (Durham, N. Carolina) (Nexis) 7 Nov. g3 Gone are the hammers, fireboxes and quenching tubs of the blacksmith's forge.