bratch (brach)

[The proper spelling of brach in this pronunciation: see brach, and cf. bratchet.] See brach. Grose. = braunite brett AS. bred, a plank: see board.] In mining, a board, plank, or brick lining or partition in a level or shaft, usually designed to form an air-pa age or confine the current of air to a certain route. Also written brettice, brettis. brattice (brat'is), v. t.; pret. and pp. bratticed, ppr. bratticing. [ The improvement of the circulation by bratticing, or separating the upward and downward currents by plates R. Wilson , Steam Boilers, p. 168. or tubes.