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but at an extreme heat will remain fixed in all ordinary situations. From the analogy of a variety of facts, it does not seem probable that any substances are absolutely fixed.

FLACOURTIA, in botany, so called in memory of Stephen de Fiacourt, a genus of the Dioecia Polyandria class and order. Natural order of Tiliaceæ, Jussien Essential character: male, calyx five-parted; corolla none; stamens very numerous: female, calyx many-leaved; corolla none; germ superior styles five to nine; berry manycelled. There is but one species.

FLAG, a general name for colours, standards, antients, banners, ensigns, &c. which are frequently confounded with each other. The fashion of pointed, or triangular flags, as now used, Rod. Toletan assures, came from the Mahometan Arabs, or Saracens, upon their seizing of Spain, before which time all the engines of war were stretched, or extended on cross pieces of wood, like the banners of a church. The pirates of Algiers, and throughout the coasts of Barbary, bear an hexagonal flag.

FLAG is more particularly used at sea; for the colours, antients, standards, &c. borne on the tops of the masts of vessels, to notify the person who commands the ship, of what nation it is, and whether it be equipped for war or trade. The admiral in chief carries his flag on the main-top; the vice-admiral on the fore-top; and the rearadmiral on the mizen-top. When a council of war is to be held at sea, if it be on board the admiral, they hang a flag in the main shrouds; if in the vice-admiral, in the fore shrouds, and if in the rear-admiral, in

the mizen shrouds.

Besides the national flag, merchant ships frequently bear lesser flags on the mizen mast, with the arms of the city where the master ordinarily resides; and on the foremast, with the arms of the place where the person who freights them lives.

FLAG, to lower or strike the, is to pull it down upon the cap, or to take it in, out of the respect or submission due from all ships or fleets inferior to those any way justly their superiors. To lower or strike the flag, in an engagement, is a sign of yielding.

The way of leading a ship in triumph is to tie the flags to the shrouds, or the gallery, in the hind part of the ship, and let them hang down towards the water, and to tow the vessels by the stern. Livy relates, that

this was the way the Romans used those of Carthage.

FLAG, to heave out the, is to put out or put abroad the flag.

FLAG, to hang out the white, is to ask or it shews when a vessel is arrived quarter; on a coast, that it has no hostile intention, but comes to trade, or the like. The red flag is a sign of defiance and battle.

FLAG officers, those who command the several squadrons of a fleet, such are the admirals, vice-admirals, and rear-admirals. The flag-officers in our pay are the admiral, vice-admiral, and rear-admiral, of the white, red, and blue.

FLAG ship, a ship commanded by a general or flag-officer, who has a right to carry a flag, in contradistinction to the secondary vessels under the command thereof.

FLAGELLARIA, in botany, a genus of the Hexandria Trigynia class and order. Natural order of Tripetaloideæ. Asparagi, Jussieu. Essential character: calyx sixparted; corolla none; berry one-seeded. There are two species.

FLAGEOLET, or FLAJEOLET, a little flute, used chiefly by shepherds and country people. It is made of box, or other hard wood, and sometimes of ivory, and has six holes besides that at the bottom, the mouthpiece, and that behind the neck. See

FLUTE.

FLAIL, an instrument for thrashing corn. A flail consists of the following parts: 1.The hand-staff, or piece held in the thresher's hand. 2. The swiple, or that part which strikes out the corn. 3. The caplins, or strong double leathers, made fast to the middle-band, being the leather thong, or tops of the hand-staff and swiple. 4. The fish skin, that ties the caplins together.

FLAIR, in the sea language. When a ship is housed in near the water, so that the work above hangs over too much, it is said to flair over. This makes the ship more roomy aloft, for the men to use their arms.

FLAMBEAU, a kind of large taper, made of hempen wicks, by pouring melted wax on their top, and letting it run down to the bottom. This done, they lay them to dry; after which they roll them on a table, and join four of them together by means of a red-bot iron; and then pour on more wax, till the flambeau is brought to the size required. Flambeaus are of different lengths, and made either of white or yellow wax. They serve to give light in the streets at night, or on occasion of illuminations.

FLAME. Newton and others have considered flame as an ignited vapour, or redhot smoke. This, in a certain sense, may be true, but, no doubt, it contains an inaccurate comparison. Simple ignition never exceeds in intensity of light the body by contact of which it was produced. But it appears to be well ascertained, that flame always consists of volatile inflammable matter, in the act of combustion and combination, with the oxgyen of the atmosphere. Many metallic substances are volatized by heat, and burn with a flame by the contact of the air in this rare state. Sulphur, phosphorus, and some other bases of acids, exhibit the same phenomenon. But the flames of organized substances are in general produced by the extrication and accension of hydrogen gas with more or less of charcoal. When the circumstances are not favourable to the perfect combustion of these products, a portion of the coal passes through the luminous current unburned, and forms smoke. Soot is the condensed matter of smoke.

As the artificial light of lamps and candles is afforded by the flame they exhibit, it seems a matter of considerable importance to society, to ascertain how the most luminous flame may be produced with the least consumption of combustible matter. There does not appear to be any danger of error in concluding, that the light emitted will be greatest when the matter is completely consumed in the shortest time. It is, therefore, necessary, that a stream of volatized combustible matter of a proper figure, at a very elevated temperature, should pass into the atmosphere with a certain determinate velocity. If the figure of this stream should not be duly proportioned; that is to say, if it be too thick, its internal parts will not be completely burned for want of contact with the air. If its temperature be below that of ignition, it will not burn when it comes into the open air. And there is a certain velocity at which the quantity of atmospherical air which comes in contact with the vapour will be neither too great nor too small; for too much air will diminish the temperature of the stream of combustible matter so much as very considerably to impede the desired effect, and too little will render the combustion languid.

We have an example of a flame too large in the mouths of the chimneys of furnaces, where the luminous part is merely superficial, or of the thickness of about an inch or VOL. III.

two, according to circumstances, and the internal part, though hot, will not set fire to paper passed into it through an iron tube; the same defect of air preventing the combustion of the paper, as prevented the interior fluid itself from burning. And in the lamp of Argand we see the advantage of an internal current of air, which renders the combustion perfect by the application of air on both sides of a thin flame. So likewise a small flame is whiter and more luminous than a larger; and a short snuff of a candle giving out less combustible matter in proportion to the circumambient air, the quantity of light becomes increased to eight or ten times what a long snuff would have afforded.

FLAMINGO, a bird, otherwise called phoenicopterus. See PHŒNICOPTERUS.

FLAMSTEED (JOHN), in biography, an eminent English astronomer, being indeed the first astronomer royal, for whose use the Royal Observatory was built at Greenwich, thence called Flamsteed House. He was born at Denby, in Derbyshire, the 19th of August, 1646. He was educated at the free school of Derby, where his father lived, and at fourteen years of age was afflicted with a severe illness, which rendered his constitution tender ever after, and prevented him then from going to the university, for which he was intended. He nevertheless prosecuted his school education with the best effect; and the, in 1662, on quitting the grammar-school, he pursued the natural bent of his genius, which led him to the study of astronomy, and closely perused Sacrobosco's book " De Sphæra," which fell in his way, and which laid the ground-work of all that mathematical and astronomical knowledge, for which he became afterwards so justly famous. He next procured other more modern books of the same kind, and among them, Street's "Astronomia Carolina," then lately published, from which he learned to calculate eclipses and the pla nets' places. Some of these being shewn to a Mr. Halton, a considerable mathematician, he lent him Riccioli's "Almagestum Novum," and Kepler's "Tabula Rudolphinæ," which he profited much by. In 1669, having calculated some remarkable eclipses of the moon, he sent them to Lord Brouncker, President of the Royal Society, which were greatly approved by that learned body, and procured him a letter of thanks from Mr. Oldenburg, their Secretary, and another from Mr. John Collins, with whom,

M

and other learned men, Mr. Flamsteed for a long time afterwards kept up a correspondence, by letters on literary subjects.

In 1670, his father observing he held correspondence with these ingenious gentlemen, advised him to take a journey to London, to make himself perfectly acquainted with them; an offer which he gladly embraced, and visited Mr. Oldenburg and Mr. Collins, who introduced him to Sir Jonas Moore, which proved the means of his greatest honour and preferment: he here got the knowledge and practice of astronomical instruments, as telescopes, micrometers, &c. On his return, he called at Cambridge, and visited Dr. Barrow, Mr. Isaac Newton, and other learned men there, and entered himself a student of Jesus College. In 1672, he extracted several observations from Mr. Gascoigne's and Mr. Crabtree's letters, which improved him greatly in dioptrics. In this year he made many celestial observations, which, with calculations of the appulses of the moon and planets to fixed stars for the year following, he sent to Mr. Oldenburg, who published them in the "Philosophical Transactions."

In 1673, Mr. Flamsteed wrote a small tract concerning the true diameters of all the planets, when at their greatest and least distances from the earth, which he lent to Mr. Newton in 1685, who made some use of it in the fourth book of his "Principia." In 1674, he wrote an ephemeris to shew the falsity of astrology, and the ignorance of those who pretended to it; with calculations of the moon's rising and setting, also occultations and appulses of the moon and planets to the fixed stars. To which, at Sir Jonas Moore's request, he added a table of the Moon's southings for that year; from which, and from Philips's "Theory of the Tides," the high-waters being computed, he found the times come very near. In 1674 too, he drew up au account of the tides for the use of the King. Sir Jonas also shewed the King, and the Duke of York, some barometers and thermometers that Mr. Flamsteed had given him, with the necessary rules for judging of the weather; and otherwise took every opportunity of speaking favourably of Flamsteed to them, till at length he brought him a warrant to be the King's astronomer, with a salary of 100l. per annum, to be paid out of the office of ordnance, because Sir Jonas was then surveyor general of the ordnance. This, how ever, did not abate our author's propensity

for holy orders, and he was accordingly ordained at Ely, by Bishop Gunning.

On the 10th of August 1675, the foundation of the Royal Observatory at Greenwich was laid; and, during the building of it, Mr. Flamsteed's temporary observatory was in the Queen's house, where he made his observations of the appulses of the moon and planets to the fixed stars, and wrote his "Doctrine of the Sphere," which was afterwards published by Sir Jonas, in his "System of Mathematics."

About the year 1684, he was presented to the living of Burslow in Surry, which he held as long as he lived. Mr. Flamsteed was equally respected by the great men his contemporaries, and by those who have succeeded since his death. Dr. Wotton, in his "Reflections upon Ancient and Modern Learning," styles our author one of the most accurate observers of the planets and stars, and says he calculated tables of the eclipses of the several satellites, which proved very useful to the astronomers : and Mr. Molyneux, in his "Dioptrica Nova," gives him a high character; and in the admonition to the reader, prefixed to the work, observes, that the geometrical method of calculating a ray's progress, is quite new, and never before published; and for the first hint of it, says he, I must acknowledge myself obliged to my worthy friend Mr. Flamsteed.

He wrote several small tracts, and had many papers inserted in the "Philosophical Transactions," viz. several in almost every volume, from the fourth to the twenty-ninth, too numerous to be mentioned in this place particularly.

But his great work, and that which contained the main operations of his life, was the "Historia Coelestis Britannica," published in 1725, in three large folio volumes; the first of which contains the observations of Mr. William Gascoigne, the first inventor of the method of measuring angles in a telescope, by means of screws, and the first who applied telescopical sights to astronomical instruments, taken at Middleton, near Leeds in Yorkshire, between the years 1638 and 1643; extracted from his letters by Mr. Crabtree, with some of Mr. Crabtree's observations about the same time; and also those of Mr. Flamsteed himself, made at Derby, between the years 1670 and 1675; besides a multitude of curious observations, and necessary tables, to be used with them, made at the Royal Ob

servatory, between the years 1675 and 1689. The second volume contains his observations, made with a mural arch of near 7 feet radius, and 140 degrees on the limb, of the meridional zenith, distances of the fixed stars, sun, moon, and planets, with their transits over the meridian; also observations of the diameters of the sun and moon, with their eclipses, and those of Jupiter's satellites, and variations of the compass from 1689 to 1719, with tables shewing how to render the calculation of the places of the stars and planets easy and expeditious; to which are added, the moon's place at her oppositions, quadratures, &c.; also the planets' places, derived from the observations. The third volume contains a catalogue of the right ascensions, polar distances, longitudes, and magnitudes of near 3,000 fixed stars, with the corresponding variations of the same: to this volume is prefixed a large preface, containing an account of all the astronomical observations made before his time, with a description of the instruments employed, as also of his own observations and instruments, with a new Latin version of Ptolemy's "Catalogue of 1026 fixed stars," and Ulegh-beig's, "Places" annexed on the Latin page, with the corrections; a small catalogue of the Arabs; Tycho Brahe's of about 780 fixed stars; the Landgrave of Hesse's of 386; Helvetius's of 1534; and a catalogue of some of the southern fixed stars, not visible in our hemisphere, calculated from the observations made by Dr. Halley at St. Helena, adapted to the year 1726.

This work he prepared in a great measure for the press, with much care and accuracy; but through a natural weakness of constitution, and the decline of age, he died of a stranguary before he had finished it, December the 19th, 1719, at 73 years of age, leaving the care of finishing and publishing his work to his friend Mr. Hodgson. A less perfect edition of the Historia Colestis had before been published without his consent, viz. in 1712, in one volume folio, containing his observations to the year 1705.

Thus then, as Dr. Keil observed, our author for more than forty years watched the motion of the stars, and has given us innumerable observations of the sun, moon, and planets, which he made with very large in struments, accurately divided, and fitted with telescopic sights; whence we may rely much more on the observations he has made than on those of former astronomers,

who made their observations with the naked eye, and without the like assistance of telescopes.

FLANKS of an army, are the troops encamped on the right and left, as the flanks of a battalion are the files on the right and left.

FLANK of a bastion, in fortification, that part which joins the face to the curtain.

FLANNEL, a kind of woollen stuff, composed of a woof and warp, and woven after the manner of baise. Various theories have been adopted to prove the utility of flanne as an article of dress: it is unquestionably a bad conductor of heat, and on that account very useful in cold weather; this is accounted for from the structure of the stuff; the fibres tonch each other very slightly, so that the heat moves slowly through the interstices, which being already filled with air, give little assistance in carrying off the heat. On this subject Count Rumford has made many experiments, from which it should seem, that though linen, from the apparent ease with which it receives dampness from the atmosphere, appears to have a much greater attraction for water than any other, yet that those bodies which receive water in its unelastic form with the greatest ease, or are most easily wet, are not those which in all cases attract the moisture of the atmosphere with the greatest avidity. "Perhaps," says he, "the apparent dampness of linen to the touch arises more from the ease with which that substance parts with the water it contains, than from the quantity of water it actually holds; in the same manner as a body appears hot to the touch in consequence of its pafting freely with its heat, while another body, which is really at the same temperature, but which withholds its heat with great obstinacy, affects the sense of feeling much less violently. It is well known that woollen clothes, such as flannels, &c. worn next the skin, greatly promote insensible perspiration. May not this arise principally from the strong attraction which subsists between wool and the watery vapour which is continually issuing from the human body? That it does not depend entirely on the warmth of that covering is clear; for the same degree of warmth produced by wearing more clothing of a different kind does not produce the same effect. The perspiration of the human body being absorbed by a covering of flaunel, it is immediately distributed through the whole thickness of that substance, and by that means exposed by a

very large surface to be carried off by the atmosphere; and the loss of this watery vapour which the flannel sustains on the one side, by evaporation, being immediately restored from the other, in consequence of the strong attraction between the flannel and this vapour, the pores of the skin are disencumbered, and they are continually surrounded by a dry and salubrious atmosphere." He expresses his surprise, that the custom of wearing flannel next the skin should not have prevailed more universally. He is confident it would prevent a number of diseases; and he thinks there is no greater luxury than the comfortable sensation which arises from wearing it, especially after one is a little accustomed to it. "It is a mistaken notion," says he," that it is too warm a clothing for summer. I have worn it in the hottest climates, and at all seasons of the year; and never found the least inconvenience from it. It is the warm bath of perspiration confined by a linen shirt, wet with sweat, which renders the summer heats of southern climates so insupportable; but flannel promotes perspiration, and favours its evaporation; and evaporation, as is well known, produces positive cold."

FLAT, in the sea-language. To flat in the fore-sail, is to hail it in by the sheet, as near the ship's side as possible; which is done, when a ship will not fall off from the wind.

FLATS, in music, a kind of additional notes, which, together with sharps, serve to remedy the defects of musical instruments, wherein temperament is required.

FLATTING, in gilding, is the giving the work a light touch, in the places not burnished, with a pencil dipt in size, in which a little vermilion is sometimes mixt. This serves to preserve and prevent its flawing when handled. See GILDING.

FLATULENCY. See MEDICINE.
FLAX. See LINUM.

Flax is an excellent commodity, and the cultivation of it a good piece of husbandry. It will thrive in any sound land, but that which has lain long fallow is best; which being well ploughed, and laid flat and even, the seeds must be sown in a warm season, about the middle or end of March, or at farthest the beginning of April; and if a wet season happen, weeding will be necessary. The best seed is that brought from the East country, which, though dear, yet easily repays the charge: this will last two or three crops, when it is adviseable to renew the seeds again. Of the best seed, two

bushels may serve for an acre; but more must be allowed of home-seed, because it grows smaller. When grown up, it ought not to be gathered before it be fully ripe; for if pulled before the blossom falls, it hackles away almost to nothing; and, though in appearance very fine, yet it has no substance, and the yarn spun of it is weak and ouzy: it not only wastes in the washing, but the linen made of it grows extremely thin in the bleaching. The pluckers should be nimble, tie it up in handfuls, set them up till perfectly dry and then house them. Flax pulled in the bloom proves whiter and stronger than if left standing till the seed is ripe; but then the seed will be lost.

FLAX, dressing of. When flax has been watered, and twice swingled, it is then to be heckled in a much finer heckle than that used for hemp. Hold the strike of flax stiff in your hand, and break it very well upon the coarse heckle; saving the hurds to make harder cloth of. This done, the strike is to be passed through a finer heckle, and the hurds coming from thence saved for middling cloth, and the tare itself for the best linen.

But to dress flax for the finest use of all, after being handled as before, and laying three strikes together, plat them in a plat of three rows, as hard and close together as you can; joining one to the end of another, till you have platted as much as you think convenient: then begin another plat, and add as many several ones as you think will make a roll; afterwards wreathing them hard together, make up the roll; which done, put as many as you judge convenient into a hemp-trough, and beat them soundly, rather more than less than you do hemp. Next open and unplat them, dividing each strike very carefully from each other; and so strike it through the finest heckle of all, whereof there are three sorts. Great care must be taken to do this gently and lightly, lest what is heckled from thence should run to knots; for if preserved soft like cotton, it will make very good linen, each pound running at least two yards and an half. The tear itself, or finest flax, will make a strong and very fine holland, running at least five yards in the pound.

FLEA. See PULEX.

FLEAM, in surgery and farriery, an instrument for letting a horse blood. A case of fleams, as it is called by farriers, comprehends six sorts of instruments; two hooked ones, called drawers, and used for cleaning wounds; a pen-knife; a sharp

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