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charcoal. It communicates a yellow colour, obtained with borax : but M. Bergman could scarcely visible, to the Auxes; and when the not produce this colour with microcosmic Cuantity is large, the globule, on cooling, con- salt. Copper simply sulphurated, when cautracts more or less of a white opacity. It is tiously and gently roasted by the exterior not precipitated by copper when dissolved; nor flame, yields at last by fusion a regulus sute do the metals precipitate it from sulphur in the rounded with a sulphurated crust.

The mass same order as' from the acids. When united roasted with borax separates the regulus more carbonic acid, it grows red on the first touch quickly. of the fame ; when the heat is increased it If a small quantity of iron happens to be Dels, and is reduced to a multitude of small present, the piece to be examined must first be globules. When united with phosphoric acid ronsted, after which it must be dissolved in boit melts, and yields an opaque globule, but is rax, and tin added to precipitate the copper. tot reduced. With Auxes it shows the same The regulus may also be obtained by sufficient appearance as oxide of lead. When minera- calcination and fusion, even without any prelized by sulphur, lead easily liquefies, and be- cipitant, unless the ore is

very poor. When ing gradually deprived of the volatile part, the pyrites cuniain copper, even in the quanvielis a distinct regulus, unless too much load- tity of the one-hundredth part of their weight, ed with iron. It may be precipitated by iron its presence may be detected by these experiand coppier.

ments. Let a grain of pyrites, of the size of A small piece of copper, either solid or folie a flax-seed, be roasted, but not so much as to ated, sometines communicates a ruby colour to expel all the sulphur; let it the be dissolved dures, especially when assisted by tin or tur- by borax, a polished rod of iron added, and the bith mineral. If the copper is a little more or fusion continued until the surface when cooled further calcined, it produces a green pellucid loses all splendour. As much borax is require globule, the ringe of which grows weaker by ed as will make the whole of the size of a grain cooling, and even verges towards a blue. By of hemp-seed. Slow fusion is injurious, and long fusion with borax, the colour is totally the precipitation is also retarded by too great desiroyed upon charcoal, but scarcely in the tenuity; but this may be corrected by the adspoon. When once destroyed, this colour can dilion of a little lime. Too much calcination scarcely be reproduced by nitre ; but it remains is also inconvenient; for by this the globule fised with microcosmic salt. If the calx or forms slowly, is somewhai spread, becomes metal to be calcined is added in considerable knotty when warm, corrodes the charcoal, dequantity during fusion, it acquires an opaquestroys the iron, and the copper does not precised on cooling, though it appears green while pitate distinctly. This defect is corrected by a pellucid and fused ; but by a still larger quan- sınall portion of crude ore. When the globule uitg it contracts an opacity even while in fusion, is properly melted, according to the directions and upon cooling a metallic splendour. Even already given, it ought to be thrown into cold when the quantity of copper is so small as water immediately on stopping the blast, in scarcely to iinge the Aux, a visible pellicle is order to break it suddenly." If ihe copper conprecipitated upon a piece of polished iron add. tained in it is less than one-hundredih part, ed to it during strong fusion, and the globule one end of the wire only has a cupreous apin its turn takes the colour of polished iron ; pearance, but otherwise ihe whole. and in this way the smallest portions of copper

Dr. Gahn has another method of examining may be discovered. The globule made green the ores of copper, namely, by exposing, a by copper, when fused in the spoon with a grain of the ore, well freed from sulphur by small portion of tin, yields a spherule of the calcination, to the action of the flame driven latler mixed with copper, very hard and brit- suddenly upon it by intervals. Althose instants tie: in this case the precipitated metal per- a cupreous splendour appears on the surface, sales the whole of the mass, and does not ad. which otherwise is black; and this splendour here to the surface. Cobalt precipitates the is more quickly produced in proportion as the cals of copper dissolved in the spoon by a fux, ore is poorer. The fame is tinged green by in a metallic form, and imparts its own colour cupreous pyrites on roasting, to glass, which nickel cannot do. Zinc also Forged iron is calcined, but can scarcely be precipitates it separately, and rarely upon its melted. It cannot be melted by burax, though own surface, as we can scarcely avoid melting it may by microcosmic salt, and then it beit. When mineralized by the carbonic acid, comes brittle. Calcined iron becomes inagnecopper grows black on the first contact of the tic by being heated on the charcoal, but melts fiame, and .elts in the spoon ; ou the char- in the spoon. The fluxes become green by coal the lower part, which touches the sup- this inetal ; but in proportion as the oxygen is port, is reduced. With a superabundance of more abundant, they grow more of a brownish marine acid, it ringes the flame of a beautiful yellow. On cooling, the tinge is much weakcolour ; but with a small quantity shows no ened, and when originally weak, vanishes en appearahce of the metal in that way. Thus the tirely. By too much saturation the globule beautiful crystals of Saxony, which are cubic, becomes black and opaque. The sulphureous and of a deep green, do not tinge the Aame, pyrites may be collected into a globule by fue though they impart. a pellucid greeuness to sion, and is first surrounded by a blue flame; microcosmic salt. An opaque redness is easily but as the metal is easily calcined, and changes

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P A N T O L O G I A.

FLU

FLU FLUKES. Worms of the intestinal order, which it spontaneonsly falls, resembling very

found frequently in the liver and brain of minute granulations: denominated fluor minesheep, and the chief source of the rot. See ral, or granular. Found in Britain, Norway, FASCIOLA.

Sweden, Spain, and Germany, white, smokeFLU'MMERY.s. A kind of food made by colour, green, violet, purple, rosy, honey-cocoagulation of wheat-flower or oatmeal (Loc.). lour, or varied with spots, blotches, or veins, FLUNG. The participle and preterit of semi-pellucid, or transparent, breaking into

three, rarely four-sided fragments, takes a fine FLUOR, in oryctology, a genus of the class polish, and' is manufactured into various vases earths, order calcareous. Consisting of carbo- and figures. hat of line and Nuoric acid ; somewhat ponder- 4. F. tabularis. In rhombic oblong ta ous, parasitical, never hard, shining in the dark, bles. Found in Switzerland, Alsace, and and crackling when heated to the degree of Saxony. boiling water ; not effervescing with acids; but 5. F. cubicus. Fluat of lime, Cubic fluor. if distilled with the mineral acids, emitting the Hardish, shining, smooth, lamellar, brittle, flooric acid gass which has the property of dis- breaking into pyramidal fragments, cubic... solving glass; melting before the blow pipe into Many varieties, cubes perfecı; or imperfect ; a transparent glass. Six species.

angles, or margins, or both truncate; margins 1. F. pulverulentus. Sandy or earthy fluor. terminating in a point, or in a three-sided pyEarthg fluat of lime. Whitish, without lus- ramid. Found in Derbyshire and Northumtre, powdery, with the larger particles not co- berland, Spain, France, Saxony, Germany, hering. Found at Kabola Poiana in the dis- &c. of the same variety of colours as F. spatotrict of Marmaros in Hungary, between two sus; most frequently pellucid, rarely opake ; beds of quartz; colour lighi gray, greenish the crystals solid or hollow, or containing a white, or blueish green; when strewed on an small drop of water, or some fossil, and placed iron plate a little below redness diffusing a blue in a decussate manner, laterally or irregular, or or pale yellow phosphorescent light; feels aggregate in a kidney or imperfectiy globular harsh, and stains a little.

form. 2. F. coinpactus. Solid or compact Auor. 6. F. pyramidalis. Pyramidal fluor ; fluor Hardish, compact, of an even texiure, diapho- spar, fluat of lime. nous, brittle, breaking into indeterminate frag- a With a single pyramid, inversed, or ments, of a common form. Found in Britain, straight, or ihree-sided, or truncate, or and near Stolberg and Strasburg, whitish-grey, six-sided. more or less passing into green, often spoiled; 6 With a double pyramid ; the pyramid fracture even or conchoidal, specific gravity four-sided. Found in Derbyshire, Dea from 3,190 to 3,165.

vonshire, and Cornwall; and in various 3. F. spatosus. Fluor spar. Sparry fuor. parts of Sweden, Saxony, and Bohemia: Hardish, shiniog, brittle, of a common form ihe colours vary as in F. spalosus. See breaking into pyramidal fragments, lamellar.

FLUORIC SPAR. Another variety, with the fragments into FLOOR ALBUS, a Inorbid secretion incilent. VOL. V.

B

cess.

to women, commonly known by the name of manner deposited if the gass is received ir? whites. See MEDICINE, and LEUCORRIEA. water, and this experiment, according to the

FLUORI ACID. Ser FLUORIC SPAR. circunstances under which the acid is disen

FLUORIC SP4R. (acide fluorique, French; gage!, exbibits a variety of singular and inte. fluss spathsuurp, Germ.). In the Transactions resting appearances. As soon as a bubble of of the Acadeor of Sciences at Berlin for 1703, gass pisses from the beak of the retort into the is contained a memoir by Margraaf on fluor water it is immediately eliminished in size from spar. This able chemist found that when the the absorption of a portion of the acid, and the abore ininral was distilled with sulphuric acid whole would be taken up if the globule did a volatile acid vapour way disengaged, which not instantly become coated with the earth dedeposited a white earth on coming into con- posited by ihat part of the acid which is ahtact with water; he also remarked that the sorbed, for the earthy film being interposed retort in which the distillation was carried on between the gass and the water prevents any was corroded and worn inio holes by the pro- further combination till the bubble reaches

Three years after, Schee'e published a the surface of the water, where it bursis. 18 valuable essay on the saine subject, in which this is performed in a jar full of water inverted he proved that fluor spar cousisted of lime over niercury, and care is taken to prevent the combined with a peculiar acid, many of the gass from being mixed with atmospheric air, proper:ies of which were investigated by him the whole of the gass is absorbed, and the with great success. Priestley then took up silex, in proportion as it is deposited, dilluses the subject, confining his attention for the itself through the liquor, which thus at lengilı most pare to the action of Huoric acid in the acquires a gelatinous consistence: when in state of ga-s. Since the date of these last ex- this state, the greater part of the earth may be periments but few additions have been made separates by putting the whole in a piece of io our knowledge of this acid and its various linen and squeezing i:. The acid liquor thus combinations.

procured being again inverted over mercury, The distinguishing property of Avoric acid will absorb an additional quantity of gass, and by is that when dry and in she state of giss it thus treating it three or four times successively, readily combines with silex, and still retains a strong fuming acid liquor may be obtained, its elastic form: hence arises the peculiar and consisting principally of Muoric acid and water, almost insurmountable difficulty of obtaining but still holding in solution a portion of silex, this substance in a state of purity.

and probably also alkali, from the decomposiFluoric acid is procured from Auor spar: tion of the glass of the retort

. If this saturated for this purpose a quantity of the mineral being liquor is mixed with a few drops of fluat of reduced to a fine powder is to be mixed in a silver, a slight precipitate of cornea takes place, thick glass retort with an equal weight of con- and the fuoric acid is thus separated from a centrated sulphuric acid : upon the applica- small portion of muriatic acid, which, when tion of a gentle heat the sulphuric acid will prepared in the foregoing manner, it is always combine with the calcareous base of the spar, found to contain. From the liquor thus puriand Ruoric gass will at the same time be libe. fied a considerable quantity of pure fluoric acid rated, and may be received in the mercurial gass may be obtained by heating it almost 10 pneumatic apparatus in the usual way. If the ebullition in a retort, and receiving the proheat applied to the retort is somewhat consi- duci in mercury. This gass appears to consist derable, and the gass is rapidly produced, the merely of Muoric acid, saturated with as much retort will give way in the space of a minute waier as it can hold in an elastic state, and at a or two, being eaten into holes by the action of moderately cool temperature seems to have no the acid ; if the process is conducted cautiously action on glass. It combines readily with and at as low a temperature as possible, the water without depositing in any earth, and has retort may be made to last a considerable while an astringent acidulous taste. A candle imlonger. The gass thus procured, wbile con. mersed in it is extinguished without any prefined over mercury, is perfectly colourless and vious change in the colour of the fome: it transparent; it has a pungent suffocating odour combines with ammoniacal gass, forming a like inuriatic acid, produces immediate death white cloud: it dissolves camphor, and is to animals which are immersed in it, extin- taken up in large quantity by oil of turpentine, guishes the name of a candle aster having pre- 10 which it communicates an orauge colour viously tinged its fame of a green colour, and and a pungent acid odour. If kept for some changes certain vegetable blues to red. Its time in a boule of soft glass it acts upon it specific gravity is considerably greater than though slightly, on which account it is a usethat of atmospheric air, but has not yet been ful precaution before putting the acid in, to ascertained with any accuracy. If this gass is live ihe bottle with a thin coating of a mixture mixed with atmospheric air, a white vapour of oil and wax. It has been proposed by some similar to but more copious than that occasion- chemists, as a method of obtaining pure liquid ed by the muriatie acid gass in the same cir- fuoric acid, to make use of a leaden retort and cumstances is the result; this appearance is receiver; in which case the fluor spar being partly occasioned by the combination of the previously reduced to an exceedingly fine pow. acid with the moisture of the air, but princi- der, is to be mixed in the retort with an equal pally by the deposition of silex, which takes weight of strong sulphuric acid; the applicaplace, ai the same time. The earth is in like tion of a gentle heat, not exceeding ihiat o! boiling water, will force into the receiver a mixture of one part of very fine pulverized fluor large quantity of acid gass, where it combines spar and two parts of sulphuric acid : then to saturation with water, and thus produces close the lid of the box, and place it on a stove, liquid fuoric acid. In this process, provided or in any other convenient situation where it the spar selecied was free from quartz, there may be exposed to as high a heat as it can bear is indeed 110 deposition of silex, but a very without risking ihe melting of the wax : fluoric notable proportion of lead is volatilized, and acid gass will be copiously disengaged, and in a remains for the most part dissolved in the short time (from one hour to three, according Exquor, which, on this account, is by no means to circumstances) the plate will be found sufso pure as the acid produced by Dr. Priesiley's ficiently corroded. See FLUOR. method.

FLU'RRY. s. I. A gust of wind; a hasty Fluoric acid has not yet been decomposed, blast (Swift). 2. Hurry; a violent commoits buse therefore is wholly unknown, and it is tion. only írum analogy that chemists suppose it to T. FLUSH. v. n. (frysen, Dutch.) 1. To contain oxygen. “A remarkable difference be- flow with violence (Morlimer). 2. To come iween the fuoric and muriatic acid is that the in haste (Ben Jonson). 3. To glow in the latter is incapable of becoining oxygenated : it skin (Collier). . 4. To shine suddenly: obsowill neither unite with oxygen in the state of lete (Spenser). gass nor wben digested with manganese. Flu- TO FLUSH. v. a. 1. To colour ; to redden oric acid combines with the alkalies and alka- (Addison). 2. To elate; to elevate (Atterbu.). line earths, with alumine and silex, and with FLUSH.Q. 1. Fresh; full of vigour (Cleave.). the metallic oxyds; the metals in a reguline 2. Affluent; abounding (Arbuthnot). slate appear to have no affinity for dry fuoric FLUSH. S. 1. Aflux ; sudden impulse ; acid, but when liquid it will dissolve iron, violent flow (Rogers). 2. Cards all of a sort. zinc, copper, and arsenic, hydrogen being at FLUSHING, a handsome, strong, and conthe same time disengaged. The order of its siderable town in Zealand, and in the island of afinities is as follows: lime, barytes, stron- Walcheren, with a good harbour, and a great tian, magnesia, potash, soda, ainmonia, alu- foreign trade. It was put into the hands of mine, and siles.

queen Elizabeth as a security for the money The oply use to which fuoric acid has been she advanced. It is one of the three places applied is engraving on glass. It appears from which Charles V. advised Philip II. to preserve Beckman that this was first practised by an

with care.

It is four miles S. W. of Middleartist of Nuremberg, in the year 1670, who burg. Lon. 3. 35 E. Lat. 51.29 N. This prepared his etching liquor by digesting toge- town was taken, in August, 1809, by the Enther nitrous acid and finely powdered fluor glish under the command of earl Chatham. spar for several hours on a warm sand bath, TO FLU'STER. v. a. (from To flush.) To and then using the clear liquor as aquafortis is make hot and rosy with drinking (Shakemployed by the copper-plate engravers. But speare). the knowlege and application of this liquor FLU'STRA. Horn-wrack. In zoology, a was confined to a few German artists, till, genus of the class vermes, order zoophyta. after the discoveries of Scheele and Priestley, Animal, a polype proceeding from porous the fluoric acid in a pure state was used for cells; stem fixed, foliaceous, membranaceous, the same purpose by various ingenious artists consisting of numerous rows of cells united in England and France. Puymaurin found together and woven like a mat. Eighteen spethe liquid acid prepared in leaden vessels accorle ciez ; inhabitants of the European or Meditering to Scheele’s process to answer very well ranean seas; one or two of the Indian and for this purpose in warın weather, but by cold -Atlantic ; eight found on the British coasts ; its activity is so much impaired as to produce adhering to fuci or other submarine substances, little effcct even in three or four days. The F. chartacea may serve as an example. This, gasseous acid however is much more effica- as its name evinces, is papyraceous, or of a cious; and being at the same time sufficiently thin semnitransparent texture, like fine paper; manageable with proper care, meriis the pre- of a very light straw colour, with cells on both ference. To engrave on glass, select a piece of sides: ihe tops of the branches sometimes digiplate glass of the requisite size, cover it with tated, sometimes irregularly divided, and trunhard engraver's wax, and with a needle or other cale like the edge of an axe : the cells are obe suitable instrument trace the intended design long-square. It is found on the British shores, as in common etching, observing that every adhering to sea-wrack, shells, and rocks, stroke passes quite through the wax to the sur- FLUTE, a musical instrument, the most face of the glass; which may be ascertained simple of those which are played by the breath by placing the plate on a sloping frame like a impelled from the lips. The common fute, portable readiog-desk, in which situation the or flute a bec, is a tube about eighteen inches light will shine through wherever the wax is in length and one in diameter; it has eight removed. When the etching is completed, holes along the side, and the end is formed lay the plate with the engraved side downwards like a beak, to apply the lips to. The Geron a frame, in a box lined with strong sheet man fute consists of a tube formed of several lead or thick tin foil, and place on the bottom joints or pieces screwed into each other, with of the box a few leaden cups containing a holes disposed along the side, like those of the

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