Page:Cyclopaedia, Chambers - Volume 1.djvu/858

 FUS

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FUS

The fourth, the Ancma, or Wind Furnace* call'd alfo Melting Furnace, and Metallic Furnace $ us'd in the Fufion of Metals, Minerals and Vitrifications.

It is call'd Wind Furnace, by reafon the Air drives forcibly in at the fame, to blow up the Coals : Its Form is much like that of the Reverbcratory Furnace 7 only leis.

For the Reverbcratory Furnace, /tfe Reverberators.

Furnace of a Mine, in the Art of War; fee Chamber and Mine.

FURNITURE, in Dialling, certain additional Points and Lines, drawn on a Dial, by way of Ornament. See Dial.

Such are the Signs of the Zodiac, Length of Days, Paral- lels of Declination, Azimuths, Meridians of the principal Cities, "Babylonick and Italian Hours, Points of the Com- pafs, i§c. See Dialling.

For drawing Furniture on Dials, the Jnalemma, or Tri- gon of Signs is an Inftrument of principal Ufe. See Ana- lemma.

FUROR tfteriffits, a Species of Madnefs, peculiar to Women, exciting them to a vehement Defire of Venery, and rendering them infatiate therewith. See Uterine Fury.

It is owing, according to SennertUS, to a too great Abun- dance of Semen, and a pneter natural Heat and Pungency thereof.

FURR, the Skin of divers kinds of Wild Beafts, drefs'd with the Hair on ; to be us'd as a Lining, or Doubling of Garments, Robes, &c. cither for Warmth, Ornament, or Distinction of Rank and Dignity.

The Robes of Kings, Dukes and Peers are lined with divers kinds of Furrs, and particularly Ermine, to render them more magnificent. See Ermine, &c.

The fame may be obferv'd of feveral chief Magi Urates 5 Judges, and Doctors of different Faculties in the Univer- sities.

The Kinds of FitfTS, or the Skins chiefly drefs'd in Alum, and with the Hair on, arc thofe of the Ermine, Sable, Squirrel, Cony, Caflor, Otter, 2)og, Fox, Wolf, 'Tiger, Sear, &c. See Skin.

The Word is form'd of the French Fourrure, a Lining; which c Du Conge derives from Furrura,, us'd, in the bar- barous Latin, for the fame thing. We alfo meet with For- ratura, fodcrata, fodramm, and fodratura, in the fame fen re.

Purr, in Heraldry, a Reprefentation of the Skins of cer- tain wiid Beafts, fcen, both in the Doublings of the Mantles of Coat Armour, and in the Armour it felrf

The Heralds ufe two Metals, five Colours, and two Furrs, or hairy Skins, Ermin and Vaite.

The Origin of thefe Furrs, Mackenzy afcribes to the Shield's being antiently cover'd with Skins; which Skins or Coverings were afterwards reprefented in the Shields : A more probable Derivation, in our Opinion, than to fay they were plac'd on Shields, becaufe they had been wore in Man- tles and Garments.

purrs either confift of one Colour, which is white • or more than one ; and thefe either two, or more than two.

Furrs of two Colours are either F)rminc, being white with black Spots; Ermines, black with white Spots; Er- minois, whofe Ground is yellow; or <Pean, which is black, pouder'd with yellow. See Ermine, Plan, &c.

Furrs of more than two Colours are Vair. See Vair, and Vairy.

FURRFER, a Perfon who trades, or works in Furrs, or lines Robes, &c. therewith. See Furr.

FURRING, in Architecture, the making good the Raf- ters Feet in the Cornice. See Rafter.

Thus, when Rafters are cut with a Knee, thefe Furrings arc Pieces which go {trait along with the Rafter, from the Top of the Knee, to the Cornice.

Alfo, when Rafters are rotten, or funk hollow in the Mid- dle, there are Pieces cut thickeft in the Middle, and taper- in" towards each End, which are nailed upon them to make them (trait. Such Pieces are called Furrs ; and the Put- ting them on, Furring the Rafters.

FUSAROLE, in Architecture, a Moulding, or Orna- ment, placed immediately under the Echinus, in the Tioric, Ionic, and Com polite Capitals

The Fufarole is a round Member, carved, in manner of a Collar or Chaplet, with oval Beads. The Fufarole mould always anfwer exactly under the Eye of the Volute in the Laic Capital.

The Italians call it Fufciclo ; and the French, from whom we borrow it, Fufarole. _ '

FUSEE, or Fusy, in Watch-work, is that conical Part, drawn by the Spring, and about which the Chain, or String is wrapp'd. See Watch.

The Spring of a Watch is the fir ft Mover. It is roll'd up in a Cylindrical Box, againft which it acls, and which it turns round in unbending itfelf. The String, or little Chain, which at one End is wound about the Fufee, and at the other

faftenM to the Spring-box, diferjgages itfelf from the Fufee, in proportion as the Box is turn'd. And hence the Motion of all the other Parts of the Spring Watch. Sec Spring.

Now the Effort, or Action of the Spring is continually di- minifhing from firft tolaft ; and of confequence, unlefs that Inequality was rectifyd, it would draw the String with more Force, and wind a greater Quantity of it upon the Box at one time than another; fb that the Movement would never keep equal time.

To correct this Irregularity of the Spring; nothing could be more happily contriv'd than to have the Spring applied to the Arms of Levers, which are continually longer as the Force of the Spring is weaker. This foreign AfBftanee, al- ways increasing as 'tis moil needed, maintains the Action, and Effect of the Spring in an Equality.

Tis for this reafon, that the Fujy is made of a conical Fi- gure. Its Axis, which is immoveable, is the Series of the Centres of all the unequal Circumferences, which compofe the Surface of the Fujy. According as the Part of a String which is untwifting, is applied to a larger Circumference, ir. is at a greater Diftance from the fix'd Point in the Axis, correfponding thereto; and of confequence the Power which draws by this String, viz. the Spring,acts with the more Ad- vantage. The Spring begins to draw by the Top of the Cone; the moil difadvantageous Part, by reafon its own Force is then the greateft. See Lever.

If the Action of the Spring diminifh'd equally, as the Pa- rallel Bafes of a Triangle do ; the Cone, which is generated ot a Triangle, would be the precife Figure required for the Fufee. But 'tis certain the weakening of the Spring is not in that Proportion ; and of confequence the Fujy mould not be conical.

In effect, Experience fhews, that it fhould not be ftrictly fo ; but that it be a little hollow toward the Middle, i. e, the Arm of the Lever muff be there a little fhorten'd ; by reafon the Action of the Spring is not fufHciently diminifh'd

of it felf. ■

'Tis a Matter of Inquiry among Geometricians what the precife Figure of the Fujy mould be ; that is, what the Curve is, by whofe Revolution round its Axis, the Solid,' whofe Figure the Fufy is to have, fhall be produced.

M. Varignon has detcrm'd this Curve. The Axis of the Fufee is alio the Axis of the Curve, which is convex on the Side toward the Axis, and of confequence concave all the way on the other, or outer fide; and the Ordinatcs arc the different Diftances wherein the String is to be with regard to all the fucceflive fix'd Points of the Axis.

The Force of the Spring multiplied by the Arm of the Lever it is applied to, each Moment, being always to make an equal Product; it follows that when the Solid of the Curve fhall be form'd, an Ordinate multiplied by the Sur- face of the Solid comprized between that Ordinate, and the greateft of all the Ordinates, viz. that of the Bafe, will al- ways yield a Product equal to that of any other Ordinates multiplied in the fame manner. For the Ordinatcs are only Arms of the Lever ; and the Parts of the Surface compre- hended between them and the Bafe are equal to the Lengths of the String, which cover them ; i. e. to the correfpondenr Forces of the. Spring : Which is what confKtutes the Equa- tion, and the Effence of the Curve.

Fusee, Fusil, or Fuse, in War, an Appendage of a Bomb, or Granado- Shell, by which the Powder or Cbmpo- fition in the Shell is fct on Fire, to do the defign'd Execu- tion. See Bome, and Granado.

The Fufee is a wooden Pipe or Tap, fill'd with Wild-fire,- or the like Compofition; and is defign'd to burn fo long, and no longer, as is the time of the Motion of the Bomb from the Mouth of the Mortar, to the Place, where it is to fall- which Time is about 27 Seconds: So that the Fife muft be contriv'd, either from the Katurc of the Compofition or the Length, of the Pipe which contains it, to burn juft that

time.'

The ufual Compofition of Fufees is two Ounces ofNitre* to one of Sulphur, and three of Gunpowder Duff. The Word is French, and literally denotes a Spindle. FUSIBILITY, that Quality in Metals, and Minerals, which difpofes them for Fufion. See Fusion.

Gold is more fufible than Iron, or Copper ; but lefs fo than Silver, Tin, and Lead. See Gold, Silver, &c.

Borax is frequently mix'd with Metals, to render them more fufible. SeeBoRAx.

FUSIL, in Heraldry, by the French called Fufee, q. d. Spindle, is a bearing, of a Rhomboidal Figure, more flcnder than the Lozenge jits upper and lower Angles being more acute than the two collateral or middle ones : as reprefented in the adjoining Figure.

FUSILIERS, in an Army, are the fame with Mufqueteers; and are called fo from the Word Fufil, a Fire-arm^

or Mufquet. See Musquet*

FUSIL-