FLUTE-SHRIKE. 768 FLUTE-SHRIKE. One of the brightly col- ored African shrikes of the genus Laniarius, so called from the clear whistle uttered by all of the species, one of which is locally called 'canarie- byter' because it preys upon certain small birds locally known as canaries. FLUTING. The moldings in the form of hol- lows or channels cut vertically on the surface of columns. They were adopted by the Greeks as ornaments to their Doric, Ionic, and Corinthian columns, and were retained by the Romans in their architecture. The Tuscan is the only style without flutes. In Doric there are usually twenty flutes on the circumference, and the curves meet with a sharp edge. These curves, in Greek Doric, are elliptical, and they are carried up across the necking to the base of the cap. In the other styles their are regularly twenty-four flutes on the circumference. These are semicircular, and are separated by a vertical band: and. before reaching the necking and the base, are terminated with semicircular top and bottom. Flutes are said to be cabled when they are filled in to about one-third of their height from the base with a convex bead. This is done to strengthen the column and protect the flutes. In countries where Roman remains were abundant, as in the south of France, fluting was sometimes adopted by the early mediaeval architects, as at Aries and Autun. In Italy, also, traces of this decoration are visible during the Middle Ages; but the flutes soon ceased to be vertical, and in Roman- esque architecture assumed many varieties of forms, such as curves, zigzags, etc., twisting round the shafts. FLUT'TER. A gossiping fop in Mrs. Cow- ley's comedy The Belle's Stratagem. FLUTTER, Sir Fopling. An affected beau, the hero of Etherege's comedy The Man of Mode, designed to ridicule Hewit. a fop of the period. FLUX (OF. flux, from Lat. fluxus, a flow, from fl/uere, to flow). The name given to sub- stances which facilitate the reduction of ores and the fusion of metals ami other bodies fusible with difficulty. The name 'white flux' i> applied to a mixture of the carbonate and nitrate of sodium or potassium. 'Black flux' is prepared by heating in close vessels ordinary cream of tartar (bitartrate of potash) with half its weight of potassium nitrate, when an intimate mixture of finely divided charcoal and carbonate of potash is obtained. The latter flux, when mixed with finely divided metallic ores, and the whole raised to a high temperature in a furnace, is not only useful iii 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, l.i stone is employed as the flux in the smelting of iron ores. Other fluxes are fluor-spar, boras, oxide of lead, etc-. See Iron nil. Metallurgy of; Copper, etc. FLUX, or Profluvium. discharge, gener ally from a mucous membrane. This old term is applied to all abnormal fluid evacuations from the body, bul especially to those from the bowels and from the uterine organs. Dysentery fq.V.) was long termed 'the bloody flux,' to distinguish it from simple diarrhcoa. Sec also Diakkikea : Menstruation. FLY. FLUXIONS. The name 'method of fluxii as' was given by Sir Isaac Newton to his calculus, and was generally employed in England and America until well along in the nineteenth cen- tury. The name, the symbolism, and the fun- damental idea upon which the method rests, were then supplanted by those of the Leibnitz calculus. Newton defined a 'fluent' as a quantity considered as gradually and indefinitely increas ing (flowing, fluxing), and added: "The velocities at which these fluents move I call fluxions" — "Quas 1 i /"i itates appello Flu-xiones,aut simplici- ter Velocitates vel Oeleritates." (Colson edi- tion. London. 1736, vol. i.. p. 54.) Briefly, his plan was this: Consider a curve described by a moving point P = (x,y), and let the rate at which x increase- | flows, fluxes) be designated by ,<-, and be called the fluxion of x. In the same way let y be called the fluxion of y. Then — is the tangent of the angle made by the tangent to the curve at P. with the c axis. It is therefore seen that t- is merely the -=- of the Leibnitz calculus. The fundamental objection to the prin- ciple is that it is based upon the idea of veloc- ity, which involves that .if time. To this ob- jection must be added that of the unfortunate notation employed by Newton. While this has some advantages in certain problems in physics, it becomes unwieldy when one desires to express successive differentiations. The method of flux- ions was used by Newton as early as 1666, and is found in the MS. of his De Analysi per 7Eqaa- tiones Numero Termvnorum Infinitas, which was circulated among his students in 1669, and in the Methodus Fluxionum ei Serierum Infinitarum, which he wrote about 1675. The term 'fluxion' seems to have been suggested to him by Cava- lieri's work. See Calculus; Newton. FLUXION TEXTURE. See Igneous Rocks. FLUX OF LIGHT. See PHOTOMETRY. FLY (AS. fleoge, led. fluga, OHG. flioga, tier. Fliege, from AS. fleogan, to fly. Icel. fljuga, OHG. fliogan, tier, fliegen; ultimately, perhaps, connected with I.at. pluma, feat her I. An insect of the group which constitutes the order Diptera, a group of very great extent and of great eco- nomic importance. Members of the order are char- acterized mainly by having only two wings, the hind wings being so abbreviated as to be repre- sented only by two small, slender rods known as halteres, or poisers, believed to be of service in assisting the insect to I eep its balance and direc- tion in flight. The only other insects which pos sess but I wo wings are the males of scale-insects of the family Coccidte. The mouth parts of the Diptera are titled for sucking and piercing, but not for gnawing. REPRODUCTION. The flies form a very large group, comprising more than 40,0(10 described
