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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, however, did not abate our author's propensity for holy orders, and be 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 neverbefore 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 : and 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.” pub
lished 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 Observatory, 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 showing 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 strangury 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 Caelestia had before been published without his consent, viz. in 1712, in one volome folio, containing his observations to the year 1705. Thus then, as Dr. Keil observed, our author, for more than forty years, watched the motions of the stars, and has given us innumerable observations of the sun, moon, and planets, which he made with very large instruments, accurately divided, and fitted with telescopic sights; whence we may rely much more on the observations he has made than on those of formers 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 hastion, 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 baize. Various theories have been adopted to prove the utility of flannel 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 touch 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 parting 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 b
wearing more clothing of a different o does not produce the same effect. The perspiration of the human body being absorbed by a covering of flannel, 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 hale 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 MEDIcLNE. 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 advisable 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 begathered 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 hackled in a much finer hackle than that used for hemp. Hold the strike of flax stiff in your hand, and break it very well upon the coarse hackle ; saving the hurds to make harder cloth of. This done, the strike is to be passed through a finer hackle, 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 to. gether 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 hackle of all, whereof there are three sorts. Great care must be taken to VOL. V.
do this gently and lightly, lest what is hackled 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 tare 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 cleansing wounds , a pen-knife; a sharppointed lancet, for making incisions; and two fleams, one sharp and the other broad pointed. These last are somewhat like the point of a lancet, fixed in a flat handle, only no longer than is just necessary to open the vein. FLEECE, the covering of wool shorn off the bodies of sheep. See Wool. FLEECY hosiery, a very useful kind of manufacture, of late invention, in which fine fleeces of wool are interwoven into a cotton piece of the common stocking texture: the nature of the manufacture is thus described: having in the common stocking frame twisted silk, cotton-yarn, &c. begin the work in the common way of making hosiery, and having worked one or more course or courses in the usul method, begin to add a coating thus: draw the frame over the arch, and then hang wool or jersey, raw or unspun, upon the beards of the needles, and slide the same off their beards upon their stems, till it comes exactly under the ribs of the sinkers; then sink the jacks and sinkers, and bring forward the frame, till the wool or jersey is drawn under the beards of the needles; and having done this, draw the frame over the arch, and place a thread of spun materials upon the needles, and proceed in finishing the course in the usual way of manufacturing hosiery with spun materials. Any thing manufactured in this way has, on the one side, the appearance of common hosiery, and on the other side the appearance of raw wool. FLEET, commonly implies a company of ships of war, belonging to any prince or state: but sometimes it denotes any number of trading ships, employed in any particular branch of commerce. In sailing, a fleet of men of war is usuall divided into three squadrons; the admiral's, the vice-admiral's, and the rear-admiral's squadron; all which, being distinguished by their flags and pendants, are Y ~
to put themselves, and, as near as may be, to keep themselves in their customary places, viz., The admiral, with his squadron, to sail in the van, that so he may lead the way to all the rest in the day-time, by the sight of the flag in the main-top-mast-head; and in the nighttime, by his lights or lanterns. The viceadmiral, and his squadron, is to sail in the centre, or middle, of the fleet; the rearadmiral, and the ships of his squadron, to bring up the rear. But sometimes other divisions are made, and those composed of the lighter ships, and best sailers, are placed as wings to the van, centre, and rear. Merchant-fleets generally take their denomination from the place they are bound to, as the Turkey-fleet, East-India fleet, &c. These, in time of peace, go in fleets, for their mutual aid and assistance: in time of war, besides this security, they likewise procure convoys of men of war, either to escort them to the places whither they are bound, or only a part of the way, to a certain place or latitude, beyond which they are judged out of danger of privateers, &c. See Convor. FLESH. See ANAToMr. FLEXION, in anatomy, is applied to the motion by which the arm or any other member of the body is bent. It is also applied to the muscles, nerves, &c. Flexion, or flexure of curves. Flexun E. FLEXOR, in anatomy, a name applied to several muscles, which are so called from their office, which is to bend the part to which they belong, in opposition to the extensors, which open or stretch them. See ANAToMY. FLEXURE of curves, in the higher ge. ometry, is used to signify that a curve is both concave and convex, with respect to a given right line or a fixed point. FLIGHT, in law. On an indictment of treason, felony, or even petit larceny, if the jury find that the party fled for it, he shall forfeit his goods and chattels, though he is acquitted of the offence; but the jury j. find the flight, it being thought too severe a punishment for that to which a man is prompted by his natural love of liberty. FLINT. A semi-transparent hard stone, of the siliceous order, of a greyish, black, or yellowish colour, well known for its general utility in giving fire with the steel. It is commonly #. in nodules, in beds of chalk or sand, and frequently exhibits indications of its having been in a soft state.
Some specimens are hollow, and intermally lined with siliceous crystals. By long exposure on the surface of the ground, they gradually become white on their upper surface first, and afterwards all over. This whiteness, in process of time, penetrates into the substance of the flint, forming a crust sometimes one-twentieth of an inch thick, which may be scraped with a knife. It has been said, that this is a conversion offlint into calcareous earth ; but we know of no proof of the fact; and as this white matter does not appear to be affected by nitric acid, we are inclined to think that the flint is merely shattered by the weather, in a manner somewhat analogous to the effect of ignition, and quenching in water, which renders it white and friable. Weigleb found the common flint to contain 80 parts in the 100 silex, 18 alumina, and 2 lime. It is used in making glass and pottery. A solution of siliceous earth, made by fusing flints with a large proportion of fixed alkali, and dissolving the mass in water, is called liquor of flints. FLOAT of a fishing line, the cork or quill that floats or swims above water. See ANGLING. Float also signifies a certain quantity of timber bound together with rafters, athwart, and put into a river to be conveyed down the stream; and even, sometimes, to carry burdens down a river with the stream. Float boards, those boards fixed to water wheels of undershot mills, serving to receive the impulse of the stream, whereby the wheel is carried round. See Mill. FLOATING bodies, are those which swim on the surface of a fluid, the most interesting of which are ships and vessels employed in war and commerce. It is known to every seaman, of what vast moment it is to ascertain the stability of such vessels, and the positions they assume when they float freely on the surface of the water. To be able to accomplish this, it is necessary to understand the princi. ples on which that stability and these positions depend. A floating body is pressed downwards by its own weight in a vertical line passing through its centre of gravity; and it is supported by the upward F. of a fluid, which acts in a vertical ine that passes through the centre of gravity of the part which is under the water; and without a coincidence between these two lines, in such a manner as that both centres of gravity may be in the same vertical line, the solid will turn on an axis, till it gains a position in which the equilibrium of floating will be permanent. From this it is obviously necessary to find what proportion the part immersed bears to the whole, to do which the specific gravity of the floating body must be known; after which it must be found by geometrical method, in what positions the solid can be placed on the surface of the fluid, so that both centres of gravity may be in the same vertical line, when any given part of the solid is immersed under the surface. These things being determined, something is still wanting, for positions may be assumed in whic the circumstances now mentioned concur, and yet the solid will assume some other position, wherein it will permanently float. However operose and dif. ficult (says an able mechanic) the calculations necessary to determine the stability of nautical vessels may, in some cases, be, yet they all depend upon the four following simple and obvious theorems, accompanied with other well known stereometrical and statical principles. Theorem 1. Every floating body dis
places a quantity of the fluid in which it
floats, equal to its own weight; and consequently, the specific gravity of the fluid will be to that of the floating body, as the magnitude of the whole is to that of the part immersed. Theorem 2. Every floating body is impelled downward by its own essential power, acting in the direction of a vertical line passing through the centre of gravity of the whole; and is impelled upward by the re-action of the fluid which supports it, acting in the direction of a vertical line passing through the centre of gravity of the part immersed; therefore, unless these two lines are coincident, the floating body thus impelled must revolve round an axis, either in motion or at rest, until the equilibrium is restored. Theorem 3. If by any power whatever a vessel be deflected from an upright position, the perpendicular distance between two vertical lines passing through the centres of gravity of the whole, and of the part immersed respectively, will be as the stability of the vessel, and which will be positive, nothing, or negative, according as the metacentre is above, coincident with, or below the centre of gravity of the vessel, Theorem 4. The common centre of gravity of any system of bodies being given in position, if any one of these bo.
dies be moved from one part of the system to another, the corresponding motion of the common centre of gravity, estimated in any given direction, will be to that of the aforesaid body, estimated in the same direction, as the weight of the body moved is to that of the whole system. From whence it is evident, that in order to ascertain the stability of any vessel, the position of the centres of gravit of the whole, and of that part immersed, must be determined; with which, and the dimensions of the vessel, the line of floatation, and angle of deflection, the stability or power either to right itself or overturn, may be found. FLOOD, among seamen, is when the tide begins to come up, or the water begins to rise, then they call it young flood; after which it is a quarter flood, half flood, and high flood. See Tipe. Floon mark, the mark which the sea makes on the shore, at flowing water, and the highest tide: it is also called highwater-mark. FLOOR. The lower part of a mine is called the floor, and the upper the roof. FLORENTINE work. When Italy, many years past, enjoyed a state of perfect tranquillity, and the minds of all ranks of the inhabitants were under the influence of religious enthusiasm, the different orders of religious, the priests, and the nobles, each endeavoured to excel the other in the splendid decorations of churches, altars, and shrines; the arts of the architect, the sculptor, and the painter, were exhausted, and the pious almost at a loss how to dispose of their riches in honour of their numerous patron-saints. Mosaic work had been invented many centuries, but some ingenious person, disdaining the comparative ease of that beautiful and expensive manner of imitating paintings, thought of Florentine work, which is performed by inserting fragments of precious stones in cement, so as to represent any subject usually treated by the pencil. Keysler mentions a Carthusian monastery, situated between Milan and Pavia, of uncommon magnificence: “the greatest part of the altars in the church are adorned with elegant representations of birds, flowers, &c. in the Florentine manner, performed by the artful position of precious stones inlaid in the marble. The convent entertains two excellent artists, a father and son, to perform these elegant works. The son, Valieri Sac, is so eminent in these performances, that the greatest mistress of embroidery would