Flux

Substance used in metallurgical and other operations as a liquid medium in which chemical reactions may take place at high temperatures. It must, therefore, be a substance fusible without difficulty and which does not act injuriously on the product. Fluorspar is largely used as a flux. IMG:content-0112.png:[merged small][merged small][merged small][merged small][graphic][merged small][merged small] IMG:content-0113.jpg:[graphic] Spotted Fly-Catcher and Pied Fly-Catcher. tropical; a few migrate n. into the U. S. The latter resemble the former in having wide mouth and rictal bristles, but differ in having leg scutellate only in front. They are also tropical, with bright markings, and include ab. 400 species.