(Mining.) The ventilating shaft of a mine out of which the air passes after having circulated through the mine; distinguished from the downcast. Called also upcast pit, and upcast shaft.
... old was sung, And temples with your praises rung; And when the song of battle rose, Or kindling wine, or lovers' woes, The poet's spirit inly burn'd, And still to you his upcast... — Poems, &c. (1790) • Joanna Baillie
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