butterfly valve (buterflivalv)

double clack-valve used in pumps. It consists e entially of two semicircular clappers, clacks, or wings hinged to a cro -rib cast in the pump-bucket, and is named from its resemblance to the wings of a butterfly when open, as represented in section in the annexed cut. It is employed in the lift-buckets of large water-pumps, and for the air-pump buckets of condensing steam-engines. Also called butterfly - cock. See clack-valve. butterfly-weed (but'er-fliwed), n. 1. A name of the North American plant Ascle Butterfly-valve. pias tuberosa; the pleurisy-root. It has a consid. erable reputation as an article of the materia medic a. It is an expectorant, a mild cathartic, and a diaphoretic, and is employed in incipient pulmonary affections, rheum a tism, and dysentery. 2. The butterfly-pea, Clitoria Mariana.