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THOSE ON NATURAL HISTORY BEING FROM ORIGINAL DRAWINGS BY EDWARDS AND
OTHERS, AND BEAUTIFULLY COLOURED AFTER NATURE.
BY JOHN MASON GOOD, ESQ. F.R.S.
OLINTHUS GREGORY, LL. D.
PHILOSOPHICAL SOCIETY, NEWCASTLE U PON-TYNE; AND
OF CAMBRIDGE ;
DEPARTMENTS OF LITERATURE.
FLU - HOM.
CROSBY AND CO.; SHERWOOD, NEELY, AND JONES; SUTTABY, EVANCE, AND CO.;
PAN TO LOGI A.
FLU FLUKES. Worms of the intestinal order, which it spontaneously falls
; resembling tery tound frequently in the liver and brain of minute granulations: denominated Auor minesheep, and the chief source of the rot. See ral, or granular. Found in Britain, Norway, FASCIOLA.
Sweden, Spain, and Germany, white, smokeFLU’MMERY. $. 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 fling,
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. nat of lime and Anoric acid; somewhat ponder- 4. F. tabularis. In rhombic oblong taous, 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 fuor. if distilled with the mineral acids, emitting the Hardish, shining, smooth, lamellar, brittle, fuoric acid gass which has the property of dis. breaking into pyramidal fragments, cubic. solving glass; melting before the blowpipe into Many varieties, cubes perfect; 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 pyEarthy Huat of lime. Whitish, without lus- ramid. Found in Derbyshire and Northumtre, powdery, with the larger particies 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 light 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 pale yellow phosphorescent lighi; feels or aggregate in a kidney or imperfectly globuharsh and stains a little.
lar form. 2. F. compactus. Solid or compact Auor. 6. F. pyramidalis. Pyramidal fluor; fluor Hardish, compact, of an even texture, diapho- spar, fluat of lime. nous, brittle, breaking into indeterminate frag- With a single pyramid, inversed, or ments, of a common form. Found in Britain, straight, or three-sided, or truncate, or and near Stolberg and Strasburg, whitish-grey, six-sided. more or less passing into green, often spotted; 6 With a double pyramid ; the pyramid fracture even or conchoidal, specific gravity sour-sided. Found in Derbyshire, Defrom 3,120 to 3,165.
vonshire, and Cornwall; and in various 3. F. spatosus. Fluor spar. Sparry fluor. parts of Sweden, Saxony, and Bohemia: Hardish, shining, brittle, of a common form the colours vary as in F. spatosus. See breaking into pyramidal fragments, lamellar. FLUORIC SPAR. Another variety, with the fragments into FLUOR ALBUS, a morbid secretion inciilent VOL. V.
to women, commonly known by the name of manner deposited if the gass is received in whites. See MEDICINE, and LEUCORRHEA. water, and this experiment, according to the
FLCORIC ACID. See FLUORIC SPAR. circumstances under which the acid is disena
FLUORIC SPAR. (acide fluorique, Fr. gaged, exhibits a variety of singular and intefluss sputhsuure, Germ.) In the Transactions resting appearances. As soon as a bubble of of the Academy of Sciences at Berlin for 1763, gas passes from the beak of the retort into the is contained a memoir by Margraaf on Auor water it is immediately diminished in size from spar. This able chemist found that when the the absorption of a portion of the acid, and the abore mineral was distilled with sulphuric acid whole would be taken up if the globule did a volatile acid vapour was disengaged, which not instantly become coated with the earth dedeposited a white earth on coming into con- posited by that part of the acid which is abtact 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 into holes by the pro- further combination till the bubble reaches cess. Three years after, Scheele published a the surface of the water, where it bursts. If valuable essay on the same subject, in which this is performed in a jar full of water inverted he proved that fluor spar consisted of lime over mercury, and care is taken to prevent the combined with a peculiar acid, many of the gas from being mixed with atmospheric air, properties 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, diffuses the subject, confining his aitention for the itself through the liquor, which thus at length most part io the action of fluoric acid in the acquires a gelatinous consistence: when in state of gas. Since the date of these last ex- this state, the greater part of the earth may be periments but few additions have been made separated by putting the whole in a piece of to our knowledge of this acid and its various linen and squeezing it. The acid liquor thus combinations.
procured being again inverted over mercury, The distingnishing property of Auoric acid will absorb an additional quantity of gas, and by is that when dry and in the state of gass it thus treating it three or four times successively, readily combines with silex, and still remains a strong foming acid liquor may be obtained, its elastic form : hence arises the peculiar and consisting principally of fuoric 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 fluor 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 Auat 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 fluoric 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 fluoric gass will at the same time be libe- fied a cousiderable quantity of pure fuoric acid rated, and may be received in the mercurial gas may be obtained by heating it almost to pneumatic apparatus in the usual way. If the ebullition in a retort, and receiving the proheat applied to the retort is somewhat consi- duct in mercury. This gass appears to consist derable, and the gas is rapidly produced, the merely of fluoric acid, saturated with as much retort will give way in the space of a minute or water as it can hold in an elastic state, and at a 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 wmperature 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 in). longer. The gass thus procured, while con- mersed in it is extinguished without any prefined over mercury, is perfectly colourless and vious change in the colour of the flane: it transparent; it has a pungent suffocating odour combines with ammoniacal gass, forining a like muriatic 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 flame of a candle after having pre- to which it communicates an orange colour viously tinged its flame of a green colour, and and a pungent acid odour. If kept for some changes certain vegetable blues to red. Its time in a bottle of soft glass it acts upon specific gravity is considerably greater than it though slightly, on which account it is a that of atmospheric air, but has not yet been useful precaution before putting the acid in, to ascertained with any accuracy. If this gas is line the hottle 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 muriatic acid gass in the same cir- fuoric acid, to make use of a leaderi 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 powacid 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 that of