there is not very much variety, are prepared on | are not supplied by springs alone, but by brooks paper, of the size of the gold plate on which the running on the surface. That portion of the water filigree is to be laid. According to this, they begin which soaks into the earth having passed through to dispose on the plate the larger compartments of a sufficient thickness of porous strata, either by the foliage, for which they use plain flat wire of a ascent or descent, will have all extraneous mixtures larger size, and fill them up with the leaves before detained, and become clear spring water. It should mentioned. To fix the work, they employ a glu- be observed, that filtration can only produce transtinous substance, made of the redhot berry, called parency, by arresting such particles of matter as boca sago, ground to a pulp on a rough stone. are in a state of mechanical mixture with the fluid, This pulp they place on a young cocoa nut about for any matter which is held in chemical solution the size of a walnut, the top and bottom being cut in the fluid will pass with it, through the pores of off. After the leaves have been all placed in order, the most minute filter, unless the substance of the and stuck on bit by bit, a solder is prepared of gold filter itself should have a greater affinity for such filings and borax moistened with water, which they matter than the fluid which contained it. In this strew over the plate; and then, putting it in the case, a new combination will be formed, and the fire for a short time, the whole becomes united. matter in solution, leaving the fluid, will be taken This kind of work on gold plate they call carrang up by the filter, not simply because the passages papan: when the work is open they call it carrang are too small to permit its particles to pass, but on trouse. In executing the latter the foliage is laid account of the superior elective attraction between out on a card, or soft kind of wood, and stuck on, the substance of the filter and the dissolved matter. as before described, with the sago berry; and the Filtration, on this principle, cannot continue to work, when finished, being strewed over with their produce a natural spring for any great length of solder, is put into the fire, when, the card or soft time; because, by the constant addition of matter, wood burning away, the gold remains connected. the filter will at last become saturated with it, or If the piece be large, they solder it at several times. choaked up. In applying this reasoning to springs, In the manufacture of badjoo buttons, they first we shall find a reason why so few springs produce make the lower part flat, and having a mould pure water, although it is always transparent. In formed of a piece of buffalo's horn indented to reality, the great natural filters which produce several sizes, each like one half of a bullet mould, springs, are almost always on an opposite principle, they lay their work over one of these holes, and, viz. that the substance which composes the filter with a horn punch, they press it into the form of a has a great affinity for the water, and its particles button. After this they complete the upper part. are thereby taken up slowly in solution, and carried When the filagree is finished, they cleanse it by off at the same time that the extraneous matters, boiling it in common salt and alum, or sometimes which are only in mixture with the water, are delime juice; and, in order to give it that fine purple tained in the pores of the filtering strata; thus we color which they call sapo, they boil it in water find few springs which have not some mineral held with brimstone. The manner of making the little in solution by the water, although invisible to the balls, with which their works are sometimes orna- eye; and in cases where heat is generated in makmented, is as follows:-They take a piece of char- ing the new combination we have spoken of, hot coal, and having cut it flat and smooth, they make springs will be produced. The most common in it a small hole, which they fill with gold dust, mineral taint which water receives in its natural and this melted in the fire becomes a little ball. filtration, is sulphate of lime or plaster of Paris: They are very inexpert at finishing and polishing this renders the water hard, as it is called, so that the plain parts, hinges, screws, and the like, being it will not produce a lather with soap, but curdles in this as much excelled by the European artists, it. Sulphate of iron or vitriol is also frequent in as these fall short of them in the fineness and mi- springs. Add to this, that in great towns, the nuteness of the foliage. drainage water which soaks into the earth is contaminated by animal matters as well as vegetable, and in such an offensive state, that the filtration through the soil can scarcely restore its purity. From all these causes, it is found that the turbid and foul waters of rivers, where altered by art to separate from their extraneous mixtures, will be more pure and wholesome as a beverage, than the generality of spring water.

FILTER. Is an apparatus employed to clarify impure water for domestic purposes; and it is also used in many arts, to separate the impurities from other fluids. A filter acts as a sort of sieve or strainer, having innumerable small passages through which the fluid can percolate slowly; but as the passages are not sufficiently large, to allow the particles of matter which are mixed with the fluid to escape, they are detained by the filter.

Gravel, in thick beds, is the most perfect natural filter; and instances may be met with, of springs from gravel producing water very nearly as pure as distilled water. Sand, when white, such as that of the seashore, is also very good; but if colored, it generally contains iron; and where the color is deep, the iron is often in such excess, that it will be communicated to the water in passing through it. Beds of sandstone filter extremely well, and also some porous limestone.

All springs of water which we are accustomed to call pure, are only rendered so by the effect of natural filtration; for the rain falling upon the surface of the earth, soaks first into the vegetable mould with which the surface is almost every where covered; in passing through this, it takes up not only dirt or earthy particles, but the remains of vegetable substances, which are in the progress toward decomposition; the water is thus rendered turbid and unwholesome for domestic purposes: FILTRUM. In Natural History, the name of a such is the state of the waters of most rivers which stone much in use in the eastern parts of the world,

and sometimes with us, for the filtrating of water | manner with their wines. The method by which intended for drinking. The Japanese are extremely these viscous bodies act in the operation is this: fond of this stone, and impute their uninterrupted they entangle themselves among the flying lee or health, and particularly their being always free light fæculencies that float in the wine, and thus from the stone and gravel, to their drinking the forming a mass specifically heavier than the wine, water thus cleared of all its heterogeneous and they sink through the body thereof like a net, carmischievous particles. The people of this, and rying down all the foulness they meet in the way many other places thereabouts, have a settled opin- to the bottom; but when the wine is extremely ion, that most diseases arise from impurities of rich, so that its specific gravity is greater than that water, and are well assured, that these impurities of the mass formed by the ingredients used in finare all lodged in the stone-filtre, and left behind by ing and the dregs or lee, this mass then rises upthe water in its passage. The manner of using the wards, and floats at the surface of the wine, which stone is this; they form a sort of mortars with very will in this case also draw off fine. thick bottoms out of the largest pieces of it, and the water is poured into these, and the stone being of a very lax and spongy texture, it soon makes its way through, and is received into a vessel placed underneath for that purpose. It being found, therefore, an easy thing for us to have our water filtered in the same manner that the Japanese have, it remains to try whether it will have all those salutary effects which the people of that part of the world give it; and this seems not to be imagined from reason and analogy. We very well know that water is frequently impregnated with saline particles, and that it also frequently dissolves by this means earthy and other matters which it otherwise could not do. But we also know, that salts dissolved in water are not to be separated by filtration; and it is equally certain, that earthy, sparry, or other matter, that is suspended in water when clear, will in like manner pass through the filter with it.

Upon the whole, we are happy enough to have no occasion for filtering stones, since our springs and rivers afford us water already pure enough to our hands; and in places where this is not the case, it is always possible to save rain-water, which will keep a long time with proper management, and is much purer than all the art in the world can make such as has once been foul.

The only instance in which a filtering-stone can be of real use, is, when there is no water to be had but that of some muddy river; in this case, the mud being a foreign body not dissolved in, but only floating among the water, it will be left behind in its passing the close structure in the filtre; but this is always to be as well obtained by letting it stand awhile to subside.

FINERY. The furnace in which metals are refined, that is, hammered and fashioned into what is called a bloom or square bar.

FINING OF WINES. The usual method of fining down wines, so as to render them expeditiously bright, clear, and fit for use, is this:-Take an ounce of isinglass, beat it into thin shreds with a hammer, and dissolve it by boiling in a pint of water; this when cold becomes a stiff jelly. Whisk up some of this jelly into a froth with a little of the wine intended to be fined, then stir it well among the rest in the cask, and bung it down tight; by this means the wine will become bright in eight or ten days. This method, however, is found to be best suited to the white wines, for the red ones the wine-coopers commonly use the whites of eggs beat up to a froth and mixed in the same

FIRE. Under this popular name, for what is now more usually treated in works of science under the titles of caloric, heat, or combustion, we may still classify a few exploded speculations, important only for the names attached to them. The opinions of the ancients respecting fire were various and fanciful. Ignorant of the leading facts which a theory is required to account for, and unassisted by experiments or tools, they generally made use of words which conveyed no definite ideas. They called it an active fermentation, an intestine motion, a repulsive agent, &c.; but no real attempt towards a rational investigation is to be found in their works. And, though some of their assertions seem to coincide with the more rational modern theories, yet that apparent coincidence must be considered as being accidental, for it is not grounded upon any regular reasoning. It must be acknowledged, however, that almost all the opinions, either ancient or modern, respecting fire, may be divided into two classes; for some of them asserted that fire was nothing more than a violent agitation, in some unknown manner, of the parts of burning bodies; whilst others attributed it to something peculiar, and sui generis, which either existed in all combustible bodies, or was communicated to them. The former, which is called the mechanical hypothesis, was believed and maintained by the most able philosophers of much earlier and much more enlightened times. The celebrated philosophers of the sixteenth century, Bacon, Boyle, and Newton, were of opinion that fire was no distinct substance from other bodies, but that it consisted entirely in the violent motion of the parts of any body. As no motion, however, can be produced without a cause, they were obliged to have resource to a mechanical force or impulse as the ultimate cause of fire in all cases. Thus Boyle tells us, that when a piece of iron becomes hot by hammering, there is nothing to make it so, except the forcible motion of the hammer impressing a vehement and variously determined agitation on the small parts of the iron.' Bacon defines heat, which he makes synonymous with fire, to be an expansive undulatory motion in the minute particles of a body, whereby they tend with some rapidity from a centre towards a circumference, and at the same time a little upwards. Sir Isaac Newton said nothing positive upon the subject; but conjectured that gross bodies and light might be convertible into one another; and that great bodies, of the size of our earth, when violently heated, might continue and increase their heat by the mutual action and reaction of their parts.

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But while the mechanical philosophers thus By the vulgar, indeed, the matter has long ago endeavored to account for the phenomena of fire, been determined, and the rays of the sun as well upon the same principles which they judged suffi- as the electrical fluid have been promiscuously decient to explain those of the universe in general, nominated elementary fire. Philosophers, however, the chemists as strenuously asserted, that fire was a have withheld their assent. The most strange fluid of a certain kind, distinct from all others, and suppositions have been made concerning the nature universally present throughout the whole globe. of both these fluids; and on the most slender Boerhaave particularly maintained this doctrine; grounds, or rather on no grounds at all, they have and in support of it argued, that steel and flint been supposed to be phlogiston itself, or to contain would strike fire, and produce the very same degree a large proportion of it. Mr. Scheele went so far of heat in Nova Zembla, which they would do in this way as to form an hypothesis, which he enunder the equator. Other arguments were drawn deavored to support by some experiments, that fire from the increased weight of metalline calces, which is composed of dephlogisticated air and phlogiston. they supposed to proceed from the fixing of the But it is now ascertained beyond dispute, that the element of fire in the substance whose weight was result of such a combination is not fire, but fixed thus increased. By these experiments Mr. Boyle air so that this hypothesis would have been altohimself seems to have been staggered: as he pub-gether untenable, even though this discovery had lished a treatise on the possibility of making fire not been made; because the dephlogisticated air and flame ponderable; though this was directly itself is not a simple but a compound substance; contrary to his own principles already quoted. For and in all cases of combustion the one part of the a long time, however, the matter was most violently air is separated from the other. It was long ago disputed; and the mechanical philosophers, though observed by Sir Isaac Newton, that heat was certheir arguments were equally inconclusive with tainly conveyed by a medium more subtile than those of their adversaries, at last prevailed, through common air; because two thermometers, one inthe prejudice in favor of Sir Isaac Newton, who, cluded in the vacuum of an air-pump, the other indeed, had scarcely taken any active part in the placed in the open air, at an equal distance from contest. The first of the chemists who attempted the fire, would grow equally hot in nearly the same to form chemistry into a regular system, was John time. The consequence of this, had he pursued Joachim Becher; but the famous George Ernest the thought, was, that fire itself was equally presStahl, (who was born in the year 1660, and died in ent in all places, and as active where there was no the year 1734) by following Becher's plan, contin- terrestrial matter as where there was. New imued to raise the edifice, endeavoring to collect the provements in the air-pump have enabled succeedprincipal facts then known into a coherent system, ing philosophers to make more perfect vacuums, by connecting them by means of general principles. such as it has been supposed even the electric matThis intelligent man, amongst other improvements, ter cannot pass through. It is not to be doubted, formed the famous phlogistic theory of fire, which however, that even there the thermometer would was almost universally adopted, notwithstanding be heated by a fire as well as in the open air. its insufficiency to account for some of the most essential phenomena of combustion. This theory continued in vogue until towards the close of the last century. The experiments on which the modern theory of combustion was first developed were those of Dr. Black, concerning what he called latent heat; on which some other names, such as absolute heat, specific fire, &c., have been be.stowed.

From these discoveries it appeared that fire may exist in bodies in such a manner as not to discover itself in any other way than by its action upon the minute parts of the body; but that suddenly this action may be changed in such a manner as no longer to be directed upon the particles of the body itself, but upon external objects: in which case we then perceive its action by our sense of feeling, or discover it by the thermometer, and call it sensible heat. It is certain, from the experiments just mentioned, that fire may exist in substances actually cold to the touch. From this discovery made by Dr. Black, along with many others in electricity, it is now almost universally allowed that fire is a distinct fluid, capable of being transferred from one body to another. But when this was discovered, another question no less perplexing occurred, viz. what kind of a fluid it was? or whether it bears any analogy to those with which we are better acquainted? Here we find two fluids, viz. the solar light, and the electric matter, both of which occasionally act as fire, and which therefore seem likely to be the same.

FIRE-ARROW. In Naval Artillery, is a small iron dart, furnished with springs and bars, together with a match impregnated with sulphur and powder, which is wound about its shaft. It is intended to fire the sails of the enemy, and is for this purpose discharged from a musquetoon or swivel gun. The match being kindled by the explosion, communicates the flame to the sail against which it is directed, where the arrow is fastened by means of its bars and springs. This weapon is peculiar to hot climates, particularly the West Indies, where the sails being extremely dry by reason of the great heats, they instantly take fire, and of course set fire to the rigging, masts, and vessel.

FIRE-BALL. A remarkable kind of meteor. Fire-balls differ from lightning, and from shooting stars, in many remarkable circumstances: as their very great bulk, being a mile and an half in diameter; their travelling a thousand miles nearly horizontally; their throwing off sparks in their passage; their changing colors from bright blue to dusky red; and their leaving a train of fire behind them, continuing about a minute. Dr. Blagden has related the history of one of these meteors, or fire-balls, which was seen the 18th of August, 1783. This was computed to be between sixty and seventy miles high, and to have travelled a thousand miles, at the rate of about twenty miles in a second. This fire-ball had likewise a train of light left

behind it in its passage, which varied in color, and in some parts of its course, and gave off sparks or explosions where it had been brightest; and a dusky red streak remained visible perhaps a minute.

FIRE-BARRELS. A sort of small barrels used for fire-ships, of a cylindrical form, as best adapted to contain the reeds with which they are filled, and more convenient for stowing between the troughs in the fire-room. The inside chambers should not be less than twenty-one inches, and thirty inches is sufficient for their length. The bottom parts are first well stored with short double-dipped reeds placed upright; and the remaining vacancy is filled with fire-barrel composition well mixed and melted, and then poured over them. The composition used for this purpose is a mass of sulphur, pitch, tar, and tallow. There are five holes, of threefourths of an inch in diameter and three inches deep, formed in the top of the composition while warm; one being in the centre, and the other four at equal distances round the sides of the barrel. When the composition is cold and hard, the barrel is primed by filling those holes with fuse-composition, which is firmly driven into them, so as to leave a little vacancy at the top to admit a strand of quick-match twice doubled. The centre hole contains two strands at their whole length, and every strand must be driven home with mealed powder. The loose ends of the quick-match being then laid within the barrel, the whole is covered with a dipped curtain, fastened on with a hoop that slips over the head of the barrel, to which it is nailed. The barrels should be made very strong, not only to support the weight of the composition before firing, when they are moved or carried from place to place, but to keep together whilst burning: for if the staves are too light and thin so as to burn very soon, the remaining composition will tumble out and be dissipated, and the intention of the barrels, to carry the flame aloft, will be frustrated. The curtain is a piece of coarse canvas, nearly a yard in breadth and length, thickened with melted composition, and covered with saw-dust on both sides.

FIRE-ENGINE. An engine for the extinguishing of fire, which consists of two forcing pumps so combined that their joint action produces a constant and powerful stream of water, which, by means of a pipe, may be directed at pleasure to any point.

scended from heaven, first upon the altar in the tabernacle, at the consecration of Aaron and his sons to the priesthood, Lev. ix. 24. It afterwards descended anew on the altar in the temple of Solomon, at the consecration of that temple, 2 Chron. vii. 1. There it was constantly maintained by the priest, day and night, without suffering it ever to go out; and with this all the sacrifices were offered that required fire. This fire, according to some of the Jewish writers, was extinguished in the days of Manasseh; but the more general opinion among them is, that it continued till the destruction of the temple by the Chaldeans; after that it was never more restored; but instead of it they had only common fire in the second temple.

The Chaldeans had a high veneration for fire, which they accounted a divinity; and in the province of Babylon there was a city consecrated to this usage, which was called the city of Ur, or of Fire. The Persians also adored God under the image or representation of fire, because it is fire that gives motion to every thing in nature. They had temples, which they called 'Pyræa,' fire temples, set apart solely for the preservation of the sacred fire. They are said to have in that empire fires still subsisting, which have burnt many thousand years. The worship of the goddess Vesta and of fire was brought into Italy by Eneas and the other Trojans, who landed there; but the Phrygians themselves had received it from the eastern nations. Fire was held in religious veneration among the Gauls; and similar sentiments and practices have prevailed in several countries of America.

FIRE-SHIPS. In the Navy, are vessels charged with combustible materials or artificial fireworks; which having the wind of an enemy's ship, grapple her, and set her on fire.

FIRE-SPOUTS. Torrents of liquid fire have sometimes burst from the earth and overwhelmed the adjacent country, in a manner somewhat different from the common eruptions of volcanoes; and are called Fire-Spouts. In 1783, three fire-spouts broke out in Iceland, in the province of Shapterfiall. Signs of the eruptions were perceived on the first of June; the earth beginning to tremble, and a continual smoke or steam rising from it. On the eighth of June the fire became visible, and the atmosphere was filled with sand, brimstone, and ashes, in such a manner as to occasion continual darkness. The three different fire-spouts, in a short time, united into one, and rolled its billows of flame so high as to be seen at the distance of more than two hundred miles; the whole country, for double that distance, being covered with a smoke or steam not to be described. The torrent of fire took its course first down, and then up the channel of the river Skapta, and entirely consumed or dried up its waFIRE, IN THEOLOGY. God has made sev- ters: at length coming to the hill, in which the river eral revelations of himself under the appearance had its source, the fiery deluge rose to a prodigious of fire: He appeared to Moses under the form of height, and overflowed the village of Buland, which a fire burning in a bush; the Holy Ghost descend- was situated upon the top of the hill; consuming ed on the apostles in tongues of fire; and the camp the houses, church, and every thing that stood in of the Israelites was guided and conducted in the its way. It still increased, spreading itself out in night-time by a pillar of fire. The Jews kept up length and breadth for many miles, drying up other the holy fire in the temple. This holy fire de-rivers besides the Skapta, overflowing a number of

FIRE-FLY. A species of flies common in Guiana, having on each side of the head, a globular luminous body, that shines like a star. They live in rotten trees in the day, and always appear at night.

villages, and converting a large tract of country In various parts of the scripture, the middle into a sea of fire. It continued its dreadful pro-region of the air is called the firmament. gress, in different directions, till the thirteenth of August; after which the fiery lake no longer spread itself, but nevertheless continued to burn for some length of time. The smoke reached as far as the island of Great Britain, where, during the whole summer of 1783, an obscurity prevailed throughout all parts of that island; the atmosphere appearing to be covered with a continual haze, which prevented the sun from appearing with his usual splendor.

FIRE, ST. ANTHONY'S. Erysipelas was first so called, it seems, in the south of France, in the twelfth century, where, and when, this disorder was exceedingly prevalent, from the success of the monks of St. Anthony, (whose profession it was to attend the sick, and who therefore carried the figure of a crutch upon the left shoulder) in curing it. They made great use of lard in these cures, hence their pigs were allowed to range free through the neighboring grounds; and that they might be distinguished from other pigs, bells were hung round their necks. These circumstances account for the figure of St. Anthony, the Egyptian hermit of the fourth century, being represented with the pig, the bell, and the letter tau upon his shoulder.

FIRE-WORKS. Compositions of sulphur, saltpetre, and charcoal, which exhibit a handsome appearance when fired off.

It is curious to observe that whilst most writers, ancient no less than modern, seem to consider the firmament as something aerial, or fluid; others, with Ptolemy, have considered it as solid and transparent like crystal. Indeed, upon the least reflection, this last idea seems to be more consonant with the nature of the word, which suggests the idea of something firm and substantial, a sort of foundation fit to support great, heavy, and magnificent objects. In fact, some writers of note have used it in this sense, and entirely independent of astronomy. Thus Bacon speaking of the principles of every subject, which human industry always endeavors to find out, says, 'The mind of man doth wonderfully endeavor, and extremely covet this, that it may not be pensile; but that it may light upon something fixt and immovable, on which, as on a firmament, it may support itself in its swift motions and disquisitions."

Considering that striking circumstance of the fixed stars constantly preserving their relative situations; it must be allowed, that Ptolemy was, not without apparent reason, induced to consider the firmament of the stars, as something solid and permanent. Previous to the very recent most accurate observations, which have shown that very slight alterations of distances do actually take place among the stars, it was not even suspected that any such thing existed; and the daily movement which they were observed to have, was considered as the common movement of them all, or rather of their firmament, which appeared to revolve round the earth once in each twenty-four hours.

FIRMAMENT. This word has been used with great latitude by sacred writers, by astronomers, by poets, and other writers. When Ptolemy of Egypt Besides this apparent daily motion, it is to be reendeavored to reconcile the phenomena of the marked that the sun returns to the equinox every celestial bodies with the prevailing philosophy of year before it returns to the same point in the the times, he supposed that the earth was immova-heavens, hence the equinoctial points have a retrobly fixed in the centre of the universe, and that the grade motion, which, though very small, in process Moon, Mercury, Venus, the Sun, Mars, Jupiter, and of time amounts to something considerable, and it Saturn, were carried round the earth by different will complete a whole revolution, so as to return spheres of solid but transparent matter. Beyond to the same point, after a great number of years. them he supposed the existence of an eighth sphere This circumstance did not escape the notice of anwhereon the fixed stars were situated, and this he cient astronomers, and their calculations respecting called the firmament of the fixed stars. In process the quantity of the annual precession, or of the of time the absurdity of this astronomical hypoth- whole revolution, were not much less accurate than esis was clearly demonstrated, in consequence of those of later times. Ptolemy reckoned the annus which the Ptolemaic spheres were utterly disre-magnus, or the grand revolution of his starry firmgarded; yet the word firmament still remained in use, its meaning, however, became less limited; so that sometimes it was used to express the region of the fixed stars; at other times it denoted a peculiar region, or some peculiar regions of the heavens, as may be deduced from the expressions, the middle firmament, the various firmaments. It has also been used to signify the sky, or the whole expanse of the heavens. Derham says, 'what an immense space is the firmament, wherein a great number of stars are seen with our naked eye! Dr. Keill, in his astronomical lectures, says, a spectator therefore living in the sun, when he looks towards the heavens, will observe its surface to be sphericalconcave, and concentrical to his eye, in which surface he will observe an innumerable multitude of stars, which we call fixed, every where dispersed throughout the whole heavens, which like so many gilded studs, with a bright lustre, adorn the firmament.'

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ament equal to thirty-six thousand ordinary years. Hipparchus came to the same conclusion. Tycho Brahe reckoned it equal to twenty-five thousand four hundred and twelve years. And the more modern astronomers, though not quite agreeing among themselves, generally reckon it equal to about twenty-six thousand years.

FIRMAN. In the East Indies, and particularly in the territories of the Great Mogul, is the passport, or permit, granted to foreign vessels, to trade within their jurisdiction.

FIRMNESS, FIRMITAS. In Philosophy, denotes the consistence of a body; or that state, wherein its sensible parts cohere, or are united together, so that the motion of one part induces a motion of the rest. In which sense, firmness stands opposed to fluidity.