FLUVANNA, a co. in central Virginia, on the James river, intersected by the Rivanna river; the James river canal passes along the s. border; 170 sq.m.; pop. '70, 9,875-5,097 colored. The surface is generally level, and the soil is fertile, producing corn, tobacco, wheat, and oats. Co. seat, Palmyra.
FLUX (fiat), I flow) is the term given to the substances employed in the arts which cause or facilitate the reduction of a metallic ore and the fusion of the metal. White flux is an intimate mixture of 10 parts of dry carbonate of soda and 13 parts of dry carbonate of potash, and is mainly instrumental in withdrawing the silica or com bined sand from mineral substances; black flux is prepared by heating in close vessels ordinary cream of tartar (bitartrate of potash), when an intimate mixture of finely divided charcoal and carbonate of potash is obtained. The latter F., when mixed with finely divided metallic ores, and the whole raised to a high temperature in a furnace, is not only useful in removing the silica, which the carbonate of potash it contains enables it to do, but the charcoal withdraws the oxygen from the metallic oxide, and causes the separation of the pure metal. Limestone is employed as the F. in
the smelting of iron ores. The other fluxes are fluor spar, borax, protoxide of lead, etc. See IRON, COPPER, etc.
FLUX (Lat. _fluxes, from fluo, I flow), a discharge, generally from a mucous mem brane. The term is applied more or less frequently to all preternatural fluid evacua tions from the body, but especially to those from the bowels, and from the uterine organs. Dysentery (q.v.) was loag termed the bloody F., to distinguish it from simple diarrhea. Another scientific term for F. is profluvium, which gives the name to a large order of diseases in Cullen's Hosology. See also CATARRH, MENSTRUATION, and, with respect to etymology only, RHEUMATISM.