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te women, commonly known by the name of manner deposited if the gass is received in? ichitos. See MEDICINE, and LEUCORREA. water, and this experiment, according to the

FLUORI! ACID. See FLUORIC STAR. circumstances under which the acid is disena

FLUORIC SPAR. (acide Nuorique, French; gager!, exhibits a variety of singular and intefluss spathsuurr, Germ.) In the Transactions resting appearances. As soon as a lubble of of the Academy of Sciences at Berlin for 1763, gass pisses from the beak of the retort into the is contained a memoir by Margraaf on fluor water it is immediately diminished in size from spar. This able chemist found inat when the the absorption of a portion of the acid, and the above ininóral 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 wbite earth on coming into con posited by ihat part of the acid which is ahtact with water; he also remarked that the sorbel, for the earthy film being interposeil retort in which the distillation was carried on between the grass and the water prevents any was corroded and worn into holes by the pro- further combination till the bubble teaches

Three years after, Schee'e published a the surface of the water, where it bursts. If valuable essay on the saine subjici, in which this is performed in a jar full of water inverted he proved that Auor spar consisted of lime over mercury, and care is taken to prevent the combined with a peculiar acid, many of the gass from bein: 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 depositei, diffuses the subject, confining his attention for the itself through the liquor, which thus at length most part to the action of Huoric acid in the acquires a gelatinous consistence: when in slate 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 separated 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 coinbinations.

procured being again inverted over mercury, The distinguishing property of fuoric acid will absorb an additional quantity of gass, and by is that when dry and in the state of guss 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 forin: hence arises the peculiar and consisting principally of Huoric 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 fuoric gass will at the same time be libe. tied a considerable quantity of pure

Almoric 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 relort, and receiving the prue heat applied to the retort is somewhat cousi- duct in mercury. This gass appears to consist derable, and the gass is rapidly produced, the merely of fluoric acid, saturated with as much retort will give way in the space of a minute waier as it can bold 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. li 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, while con- mersed in it is extinguished without any prefined over mercury, is perfectly colourless and vious change in the colour of the Home: it transparent; it has a pungent suffocating odour combines with ammoniacal gass, forming 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 name of a candle after having pre- 10 which it communicates an orange 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 line the 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 fuor 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 at the same time. The earth is in liko tion of a gentle heat, not exceeding that of boiling water, will force into the receiver a mixture of one part of very fine pulverized fluor lasze 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 Auoric acid. In this process, provided or in any other convenient situation where it the spar selected was free from quariz, there may be exposed to as high a heat as it can bear is indeed no deposition of silex, but a very without risking the melting of the wax: fuoric tiötable proportion of lead is volatilized, and acid gass will be copiously disengaged, and in a remalus for the most part dissolved in the short time (from one hour to three, according luor, which, on this account, is by no means to circumstances) the plate will be found sufso pare as the acid produced by Dr. Priestley's ficiently corroded. See FLUOR. Deihod.

FLU'RRY. s. I. A gust of wind; a hasty Fluoric acid has not yet been decomposedl, blast (Swift). 2. Hurry; a violent commoiu buse therefore is wholly unknown, and it is tion. only from analogy that chemists suppose it to To FLUSH. v. n. (frysen, Dutch.) 1. To contain oxygen. A remarkable difference be- flow with violence (Mortimer). 2. To come iven the fuoric and muriatic acid is that the in haste (Ben Jonson). 3. To glow in the latier is incapable of becoming oxygenated : it skin (Collier). . 4. To shine suddenly: obsowill deither unite with oxygen in the state of lete (Spenser). pass nor when digested with manganese. Flu- To Flush. v. a. 1. To colour; to redden cric acid combines with the alkalies and alka- (Addison). 2. To elate ; to elevate (Atterbu.). Ime earths, with alumine and silex, and with FLUSH. a. 1. Fresh; full of vigour (Cleave.). the metallic oxyds; the metals in a reguline 2. Afluent; abounding (Arbuthnot), state appear to have no affinity for dry fuoric

FLUSH. S. 1. Afflux ; sudden impulse ; acid, but when liquid it will dissolve irou, violent flow (Rogers). 2. Cards all of a sort. zine, 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 atinities is as follows: lime, barytes, stron- Walcheren, with a good harbour, and a great tian, maynesia, potash, soda, ammonia, alu foreign trade. It was put into the hands of bine, and silex.

queen Elizabeth as a security for the movey 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 1070, 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 Enibei nitrous acid and finely powdered Muor glish under the command of earl Chatham. sper for several hours on a warm sand bath, TO FLU'STER. v. a. (from To flush.) To and then using the clear liquor as aquasortis 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 Avoric 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. Paymaurin found together and woren like a mat. Eighteen spethe liquid acid prepared in leadeu vessels accordo cies; 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 warm weather, but by cold Atlantic ; eight found on the British coasts ; iis activity is so much impaired as to produce adhering to fuçi or other submarine substances, little effect even in three or four days. The F. chartacea may serve as an example. This, passeous acid however is much more effica- as its name evinces, is papyraceous, or of a cious; and being at the same time sufficiently thin semitransparent texture, like fine paper ; manageable wiih proper care, meriis the pre- of a very light straw colour, with cells on both ferelice. 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 obo suitable instrument trace the intended design long-square. li is found on the British shores, 35 in common etching, observing that every adhering to sea-wrack, shells, and rocks. stroke pa:ses 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 reading-desk, in which situation theor 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 Gerou 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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common Aute. It is stopped at the upper end, nistry, applied to those substances, oteris
and furnished with moveable brass or silver line mixtures, that are added to mineral: or
kevs, which, by opening and closing certain metallic ore, to assist in the process of reduce
holes, serve to iemper the tones to the various tion.
flats and sharps. In playing this instruinent White flur is made simply by mixing equal
the performer upplies his under lip 10 2 hole parts of tartar or cream of tartar and nitre, and
about two inches and a half from the upper deflagrating them in a clean crucible. The
extremity, wliile ihc fingers, by their action on vitrous acid burns the carbonaceous part of
the holes and keys, accommodate the tones to the tastar, and the mixed alkalies of the niir
the notes of the composition.

and iartar alone remain. This flur is, there. FLUTES, or FlutiXG5, ir architecture, fore, little else than a pure subcarbonat of poichannels or cavities running perpendicularly ash. The mixture of these substances before along the shaft of a column or pilaster. They deflagration is called crude flux. But of all are chiefly affected in the Tonic order, in the saline reducing substances that most frewhich they had their first rise ; though they quently employed is lilack flut. This is made are also used in all the richer orders, as the by deflagrating in a large crucible a mixture of Corinthian or Composite; but rarely in the one part of nitre and two of turtar; and differ3 Doric; and scarce ever in the Tuscan. Their from the former in containing, besides carbonumber is usually twenty-four, though in the nat of potash, a quantity of charcoal of the tarDoric it is only twenty. Each Aute is hollow- iar, which there may not beca nitre enough to ed exactly in a quadrant of a circie. Between

It therefore both assists in the futhe flutes are liitle spaces that separate them, sion of ores by its alkaline ingredient, and called by Vitruvius, striæ, and by us, lists; oxygenates, and reduces them to the metallic though in the Doric, the Autes are frequently state by means of its carbon. made to join each other, without any inter- In making this last tlux, the materials, premediate space at all, the list being sharpened viously well mixed, should be thrown by small off to a thin edge, which forms a part of each quantities into a red-hot crucible, and loosely flute.

covered after each projection ; and as soon as To Flute. r. a. To cut columns into hol. the last portion is defiagrated, it should be relows.

moved from the fire, and kept in well.closed T. FLUÄTTER. v. n. (zlozeran, Sixon.) bottles to prevent the deliquescence of the al1. To take short fights with great agitation of kali. Bergman however uses the term Aux in the wings (Deuteronomy). 2. To more about a much more extensive sense ; and intends by with great show and busile without conse- it not only substances useful in the reduction quence (Grew). 3. To be moved with quick of metals, but substances capable of analyzing vibrations or undulations (Pope). 4. To move by the blowpipe saline, earthy, or inflammalle irregularly (Howel).

matters. The fluxes recomniended by him for To Flu'tter. V.n. 1. To drive in disorder, this purpose are the following. like a flock of birds suidenly roused (Shake 1. The phosphoric acid, or rather the mispeare). 2. To hurry the mind. 3. To dis- crocosmic salt, as it is called, which contains order the position of any thing.

that aci partly saturated with mineral, partly FLUTTER. S. (from the verb.) 1. Vibration; with amnionia, and loaded besides with much undulation (Addison). 2. Hurry ; tumult; water. This salt, when exposed to the flame, disorder of mind. 3. Confusion; irregular boils and foams violently, with a continual position.

crachling noise, wil the water and ammonia FLUVIATICK. a. (furiaticus, Latin.) have flown oti: afterwards it is less agitated, Belonging to rivers.

sending forih something like black scoria arisFLUX, s. (flurus, Latin.) 1. The act of ing from the burned gelatinous part: these, flowing; passage (Digly). 2. The state of however, are soon dispelled, and exhibit a pelpassing away and giving place to others (Bro.). lucid sphericle encompassed by a beautiful 3. Any flow or issue of matter (Arbuthnol). green cloud, which is occasioned by the de. 4. Dysentery; disease in which the bowels flagration of the phosphorus, arising from the are excoriated and bleed; bloody flux (Mali- cxirication of the acid by means of the inflamfa). 5. Excrement; that which falls from mable matter. The clear globule which rebodies (Shakspeare). 6. Concourse; conflu- mains, upon the removal of the fame, contience (Shakspeare). 7. The state of being nues longer soft than that formed by borix, melted. 8. That which mingled with the and therefore is more fit for the addition of the body makes it melt.

matter to be dissolved. The aminonia is esa FLUX AND REFLUX

See pelled by the fire ; therefore an excess of acid Tues.

remains in what is left behind, which readily Flux (fluss, Gernian), in chemistry, any attracts moisture in a cool place. 2. Soda, substance which is added to another to assist when put upon charcoal, melts superficially, its fusion when heat is applied. Thus alkali is penetrates the charcoal with a crackiling noise, a flux for flint, as when mixed with it in due and then disappears. In the spoon it yields a proportion, and heated, it causes it to melt permanent and pellucid sphericle, as long as it into the compound called glass.

is liept Auid by the blue apex of the flane; The term flux is almost exclusively, in che. but when the heat is diminished, it becomno




opaque, and assumes a milky colour. It ate easily roll off the charcoal, especially when of Licks sereral earthy mallers, particularly those the size of a grain of pepper. Smaller pieces, of the siliceous kind, but cannot be employed therefore, ought either to be used, or they ou charcoal. 3. Crystallized Lorax, exposed should rest in hollows made in the charcoal. to the flame urged by the blowpipe, or char- On their first melting they assume a polished coal, first becomes opaque, white, and exces- surface, an appearance always retained by the sisely swelled, with various protuberances, or perfect metals; but the imperfect are soon obbranches proceeding out from it. When the scured by a pellicle formed of the calx (oxide) water is expelled, is easily collects itself into a of the metal. The colours communicated by mass, which, when well fused, yields a trans- the calces vary according to the nature of the parent sphericle, retaining its transparency metal from which the calx is produeed. Some even after cooling. If calcined borax be eni- of the calces easily recover their metallic form played, the clear sphericle is obtained the by simple exposure to fame upon the charcoal ;

others are reduced in this way with more diffiHaving provided every thing necessary, the culty; and some not at all. The reduced calces following directions are next to be attended to. of the volatile metals immediately fly off from 1. A common Lallow candle, not too thick, is the charcoal. In the spoon they exhibit glogenerally preferable to a wax candle, or w a bules; but it is very difficult to prevent them lainp. The snuff must not be cut too short, from being first dissipated by the blast. as the wick should bend towards the object. The metals are taken up by the fluxes ; bat 2. The weaker exterior flame must first be di- as soda yields an opaque spherule, it is not to be rected upon the object, until its effects are dis- made use of. Globules of borax (lissolve and covered, after which the interior Aame must melt any metallic calx; and, unless too much be applied. 3. We must observe with atten- loaded with it, appear pellucid and coloured. tion whether the matter decrepitates, splits, A piece of metal calcined in flux produces the swells, vegetates, boils, &c. 4. The piece ex- same effect, but more slowly. A portion of posed to the flanie should scarcely ever exceed the calx generally recovers its metallic form, ihe size of a pepper-corn, but ought always 10 and floats on the melted matter like one or be large enough to be taken up by the forceps. more excrescences. 5. A small piece should be added separately to The calces of the perfect metals are recluced euch of the fluxes ; concerning which it must by borax in the spoon, and adhere to it at the be observed whether it dissolves wholly or only point of contact, and there only. The microin part; whether this is effected with or with- cosmic salt acts like borax, but cloes not reduce qui effervescence, quickly or slowly; whether the inetals. It attacks them more powerfully the mass is divided into a powder, or gradually on account of its acid nature ; at the same time and externally corroded ; with what colour the it preserves the spherical form, and therefore is glass is tinged, and whether it becomes opaque adapted in a peculiar manner to the investigaor remains pellucid.

tion of metals. Having given these directions, M. Bergman The tinge communicated to the Aux freproceeds next to consider the subjects proper to quently varies, being different in the fused and be examined by the blow pipe. These he di- in the cooled globule; for some of the dissolve vides into four classes : 1. Saline ; 2. Earthy; ed calces, while fused, show no colour, but ac3. Inflammable; and 4. Metallic. As the sub- quire one while cooling ; but others, on the ject, however, is treated at considerable length, contrary, have a much more intense colour we shall reser the reader to M. Bergman's while in the state of fluidity. Should the transwritings, and confine ourselves in this place to parency be injured by too great a concentration what he has advanced concerning the last of of colour, the globule, on compressing it with these subjects, namely, metallic substances. the forceps, or drawing it oui into a thread,

The perfect metals, when calcined (oxyge- will exhibit a thin and transparent mass; but nated) in the moist way, recover their former if the opacity arises from supersaturation, more nature by simple fusioni: The imperfect metals Aux must be added ; and as the Auxes attract are calcined by fire, especially by the exterior the metals with uncqual forces, the latter prefiame; and then, in order to their being re- cipitate one another. duced, indispensably require the contact of an Metals when mineralized by acids have the inflammable substance. With respect to fn- properties of metallic salis ; when mineralized sibility, the two extremes are mercury and pla- by carbonic acid, they possess the properties of tina; the former being scarcely ever seen in a calces, that volatile substance being easily exsolid form, and the latter almost as difficult of pelled without any effervescence; but when fusion. The metals, therefore, may be ranked combined with sulphur they possess properties in this order, according to their degrees of fusic of a peculiar kind. They may then be melted, bility. 1. Mercury; 2. Tin; 3. Bisinuth; 4. or even calcined upon the charcoal, as also in Lead; 5. Zinc; 6. Antimony; 7. Silver; 8. a golden or silver spoon. The volatile parts Gold; 9. Arsenic ; 10. Cobalt; 11. Nickel; are distinguished by the smell or smoke; the 12. Irou ; 13. Manganese; 14. Platinum. The fixed residua, by the particles reduced or prelast two do not yield to the blowpipe, and in- cipitated upon iron, or from the tinge of the deed forged iron does not melt without diffi- fluxes. culty; but cast iron perfectly.

Gold in its metallic state fuses on the charBletals in fusion affect a globuluar form, and coal, and is the only metal which remains un

of copper

changed. It may be oxygenated in the moist through the glass it appears of a gold colour ;
way by solution in aqua regia ; but to calcine but care must be taken not to crack the glass.
it also by fire, we must pursue the following Calcined silver precipitaled from nitrous acid
method : To a globule of microcosmic salt, let by tixed alkali is easily reduced. The micro-
there be added a small piece of solid gold, of cosmic acid dissolves it speedily and copiously;
gold leaf, purile mineral, or, which is best of bui on cooling it becomes opaque, and of a
all, of the crystalline salt formed by a solution whitish yellow, which is also sometimes the
of gold in aqua regia containing sea-salt. Let case with leaf-silver. Copper is discovered by
this again be melied, and added while yet solt a green colour, and sometimes by that of a
to turbith mineral, which will immediately ruby, unless we choose rather to inspute that to
grow red on the contact. The fusion being guild. The globules can scarcely be obtained
afterwards repeated, a vehement effervescence pellucid, unless the quantity of calx is very
arises ; and when this is considerably diminish: small; but a longer fusion is necessary to pro-
ed, let the blast be stopped for a few moments, duce an opacity with borax. The globule,
again begun, and so continued until almost all loaded with dissolved silver during the time of
the bubbles disaj,pear. After ibis the sphe.. its fusion in the spoon, covers a piece
Jule, on cooling, assumes a ruby colour ; but with silver, and becomes itselt' of a pellucid
if this does not happen, let it be just made sost green: antimony quickly takes away

the milky by the exterior Hame, and upon hardening, this opacity of dissolved luna cornea, and separates tinge generally appears. Should the process the silver in distinct grains. Cobalt, and most fail at first, owing to some minute circum- of the other metals, likewise, precipitate silver stances which cannot be described, it will suc- on the same principles as in the moist way, ceed on the second or third trial. The ruby- viz. by a double elective attraction. This mecoloured globule, when compressed by the for. tal, when mineralized by marine and vitriolic ceps while hoi, frequently becomes blue; by acids, yields a natural luna cornea, which prosudden fusion ii generally assumes an opul co- duces a number of small metallic globules on lour, which by refraction appears blue, and by the charcoal : il dissolves in microcosmic salt, reflection of a brown red. If further urged by and render: it opaque, and is reduced, partially the fire il loses all colour, and appears like wa. at least, by borax. Sulphurated silver, called ter; but the redness may be reproduced several also the glassy ore of that metal, fused upon times by the addition of turbith mineral. The charcoal, easily parts with the sulphur it conflux is reddened in the sanie manner by the ad. tains : so that a polished globule is often prodition of vin instead of turbiih; but it has a duced, which, if necessary, may be depurated yellowish hue, and more easily becomes by borax. The silver may also be precipitated opaque; while the redness communicated by by the addition of copper, iron, or manganese. turbith mineral bas a purple tinge, and quite When arsenic makes part of the compound, as resembles a ruby. Borax produces the same in the red ore of ar-enic, it must first be freed phenomena, bui more rarely; and in all cases from the sulphur by gentle roasting, and finally the slightest variation in the management of entirely depurated by borax. li decrepitates in the fire will make the experiment fail entirely. the fire at first.

The ruby colour may also be produced by Copper, together with sulphur and arsenic copper ; whence a doubt may arise, whether it mixed with silver, called the while ore of sil. is the gold or the remains of the copper that ver, yields a regulus having the same alloy. produce this effect. M. Bergman ihinks it Galena, which is an ore of lead containing probable that both may contribute towards it, sulphur and silver, is to be freed in the saine especially as copper is often found to contain manner from the sulphur; after which the gold.

lead is gradually dissipated by alternately meltThis precious metal cannot directly be mi- ing and cooling, or is separated in a cupel from neralized by sulphur : but by the medium of the galena by means of the flame. Bergman iron is sometimes furmed into a golden pyrites. has not been able to precipitate the silver diHere, however, the quantity of gold is so small, stinct from the lead, but ihe whole mass bethat a globule can scarcely be extracted from it comes malleable; and the same is true of lin, by the blowpipe.

but the mass becomes more brittle. Grains of native platinum are not affected Pure mercury Aies off from the charcoal by the blowpipe, either alone or mixed with with a moderate heal, the fixed heterogeneous fluxes; which, however, are frequently tinged matters remaiving behind. When calcined, green by it: but platinum, precipitated from it is easily reduced and dissipated, and the fluxes aqua regia by vegetable or volatile alkali, is re. take it up with effervescence ; but it is soon duced by microcosmic salt 10 a small malleable totally driven off. When mineralized by sulglobule. Our author has been able to unite phur, ii liquefies upon the charcoal, burts with seven or eight of these into a malleable mass; a blue flame, smokes, and graduilly disappears; but more of them produced only a britele one. but, on exposing cinnabur to the fire on a poPlatinum scarcely loves all its iron, unless re. lished piece of copper, the mercurial globules duced to very thin fusion.

are fixed upon it all round. Silver in iis metallic siate easily melis, and Lead in its meialtic stale readily melts, and resists calcination. Silver leaf fastened by continues to retain a metallic splendour for means of the breath, or a solution of borax, some time. By a more intense heat it boils inay casily be fixed on it by the flame, and and smokes, forming a yellow circle upon the

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