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NECK, is that slender part situated be tween the head and the trunk of the body. See ANATOMY.

NECTARINE. See PERSICA. NECTARIUM, in botany, according to Linnæus, is a part of the corolla, appropriated for containing honey, that oozes from the plant, and is the principal food of bees and other insects.

NECTRIS, in botany, a genus of the Hexandria Digynia class and order. Natural order of Tripetaloideæ. Junci, Jussieu. Essential character: calyx one-leafed, sixparted, coloured; corolla none; styles permanent; capsules two, superior, ovate, onecelled, many-seeded. There is but one species, viz. N. aquatica. This plant grows in ponds, lakes, and rivers, that have not a rapid current, pushing out long, knotted, fistulous stems, with a pair of leaves at each joint. The flowers come out from the axils of the leaves, on a long peduncle; the three outer leaves of the calyx are green on the outside and yellow within. It is a native of Guiana and the island of Cayenne.

NECYDALIS, in natural history, a genas of insects of the order Coleoptera. Antennæ setaceous or filiform; four feelers, filiform; shells less than the wings, and either narrower or shorter than the abdomen; tail simple. There are about forty species, in two sections. A. Antennæ setaceous; shells shorter than the wings and abdomen. B. Antennæ filiform; shells subulate, as long as the body. N. humeralis, is found in this country: shells subulate, black, yellow at the base, without lines; body and legs black.

NE exeut Regno, is a writ to restrain a person from going out of the kingdom without the King's licence. Within the realm the King may command the attend ance and service of all his liegemen; but he cannot send any man out of the realm, not even upon the public service, except seamen and soldiers, the nature of whose employment necessarily implies an exception. This writ is now mostly used where a suit is commenced in the Court of Chancery against a man, and he, intending to defeat the other of his just demand, or to avoid the justice and equity of the court, is about to go beyond sea. If the writ be granted on behalf of a subject, and the party taken, he either gives security by bond in such sum as is demanded, or be satisfies the court by answering (where the answer is not already in), or by affidavit, that he intends not to go out of the realm, and gives such reason

able security as the court directs, and then he is discharged.

NEEDLE, a very common little instrument or utensil, made of steel, pointed at one end, and pierced at the other, used in sewing, embroidery, tapestry, &c.

Needles make a very considerable article in commerce, though there is scarcely any commodity cheaper, the consumption of them being almost incredible. The sizes are from number 1, the largest, to number 25, the smallest. In the manufacture of needles, German and Hungarian steel are of most repute. In the making them, the first thing is to pass the steel through a coal fire, and under a hammer, to bring it out of its square figure into a cylindrical one. This done it is drawn through a large hole of a wire-drawing-iron, and returned into the fire, and drawn through a second hole of the iron, smaller than the first, and thus successively, from hole to hole till it has acquired the degree of fineness required for that species of needles, observing every time it is to be drawn that it be greased over with lard, to render it more manageable. The steel thus reduced to a fine wire, is cut in pieces of the length of the needles intended. These pieces are flatted at one end on the anvil, in order to form the head and eye: they are then put into the fire to soften them further, and thence taken out and pierced at each extreme of the flat part on the anvil, by force of a puncheon of well-tempered steel, and laid on a leaden block to bring out, with another puncheon, the little piece of steel remaining in the eye. The corners are then filed off the square of the heads, and a little cavity filed on each side of the flat of the head: this done, the point is formed with a file, and the whole tiled over: they are then laid to heat red hot on a long flat narrow iron, crooked at one end, in a charcoal fire, and when taken out hence, are thrown into a bason of cold water to harden. On this operation a good deal depends: too much heat burns them, and too little leaves them soft: the medium is learned by experience. When they are thus hardened, they are laid in an iron-shovel on a fire, more or less brisk in proportion to the thickness of the needles; taking care to move them from time to time. This serves to temper them, and take off their brittleness: great care here too must be taken of the degree of heat. They are then straitened one after another with the hammer, the coldness of the water used in hardening them having

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twisted the greatest part of them. The next process is the polishing them. To do this they take twelve or fifteen thousand needles, and range them in little heaps against each other on a piece of new buckram sprinkled with emery-dust. The needles thus disposed, emery-dust is thrown over them, which is agam sprinkled with oil of olives; at last the whole is made up into a roll, well bound at both ends. This roll is then laid on a polishing-table, and over it a thick plank loaden with stone, which two men work backwards and forwards a day and a half, or two days, successively; by which means the roll thus continually agitated by the weight and motion of the plank over it, the needles withinside being rubbed against each other with oil and emery, are insensibly polished. After polishing they are taken out, and the filth washed off them with hot water and soap: they are then wiped in hot bran, a little moistened, placed with the needles in a round box, suspended in the air by a cord, which is kept stirring till the bran and needles be dry. The needles thus wiped in two or three different brans, are taken out and put in wooden vessels, to have the good separated from those whose points or eyes have been broke either in polishing or wiping: the points are then all turned the same way, and smoothed with an emnery stone turned with a wheel. This operation finishes them, and there remains nothing but to make them into pack ets of two hundred and fifty each.

NEEDLE, magnetical, in navigation, a needle touched with a loadstone, and sus. tained on a pivot or centre: on which play ing at liberty, it directs itself to certain points in or under the horizon; whence the magnetical needle is of two kinds, viz. horizontal and inclinatory.

Horizontal needles are those equally balanced on each side the pivot that sustains them: and which, playing horizontally with their two extremes, point out the north and south points of the horizon.

In the construction of the horizontal needle a piece of pure steel is provided, of a length not exceeding six inches, lest its weight impede its volubility, very thin, to take its verticity the better, and not pierced with any holes, or the like, for ornament sake, which prevent the equable diffusion of the magnetic virtue. A perforation is then made in the middle of its length, and a brass-cap or head soldered on, whose inner cavity is conical, so as to play freely on a style or pivot headed with a fine steel-point.

The north point of the needle in our hemisphere is made a little lighter than the southern; the touch always destroying the balance, if well adjusted before, and rendering the north end heavier than the south and thus occasioning the needle to dip.

The needle is not found to point precisely to the north except in very few places, but deviates from it more or less in different places, and that too at different times, which deviation is called its declination or variation from the meridian.

Inclinatory or dipping-needle, a magnetical needle, so hung, as that, instead of playing horizontally and pointing out north and south, one end dips or inclines to the horizou, and the other points to a certain degree of elevation above it. Or a dippingneedle may be defined to be a long straight piece of steel, every way poised on its cen. tre, and afterwards touched with a loadstone, but so contrived as not to play on the point of a pin, as does the common horizontal needle, but to swing in a vertical plane, about an axis parallel to the horizon; and this to discover the exact tendency of the power of magnetism. See MAGNETISM.

To find the longitude or latitude by the dipping-needle. If the lines of equal dip below the horizon be drawn on maps or sea charts from good observations, it will be easy, from the longitude known, to find the latitude, and from the latitude known to find the longitude, either at sea or land. Suppose, for example, you were travelling or sailing along the meridian of London, and found the angle of dip with a needle of one foot to be 75°, the chart will show that this meridian and the line of dip meet in the latitude 53° 11', which is, therefore, the latitude sought. See LATITUDE. Or suppose you were travelling or sailing along the parallel of London, that is, in 51° 32′ north latitude, and you find the angle of dip to be 74°. The parallel and the line of this dip will meet in the map in 1° 46′ of east longitude from London, which is therefore the longitude sought.

NEEDLE stone, in mineralogy, a species of the Zeolite family, found in Iceland and Britanny. Its common colour is a yellowish white. It occurs massive, and crystallized in rectangular four-sided acicular prisms, which are generally aggregated. It is distinguished from the radiated zeolite, by being harder and more brittle, by its lustre being greater, and of the vitreous kind.

NEGATIVE, in general, something that implies a negation. Thus we say, negative

quantities, negative signs, negative powers, the human species, who are entirely black, &c. See ALGEBRA. and are found in the torrid zone, especially in that part of Africa which lies between the tropics. See MAN; SLAVE; Slave trade.

Our words and idea, says Dr. Watts, are so unhappily linked together, that we can never know which are positive, which negative ideas, by the words that express them: for some positive terms denote a negative idea, as dead; and there are both positive and negative terms invented to signify the same and contrary ideas, as unhappy and miserable. To this may also be added, that some words, which are negative in the original language,'scem positive in English, as abyss. The way, therefore, to know whether any idea be negative or not, is to consider whether it primarily implies the absence of any positive being, or mode of being; if so, then it is a negative idea, other wise a positive one.

NEGATIVE sign, the sign of subtraction, or that which denotes something in defect. The use of the negative sign in algebra is attended with several consequences that at first sight are admitted with some difficulty, and has sometimes given occasion to notions that seem to have no real foundation. This sign implies, that the real value of the quantity represented by the letter to which it is prefixed, is to be subtracted; and it serves, with the positive sign, to keep in view what elements or parts enter into the composition of quantities, and in what manner, whether as increments or decrements, that is, whe-ther by addition or subtraction, which is of the greatest use in this art. Hence it serves to express a quantity of an opposite quality to a positive, such as a line in a contrary position, a motion with opposite direction, or a centrifugal force in opposition to gravity; and thus it often saves the trouble of distinguishing, and demonstrating separately, the various cases of proportions, and preserves their analogy in view. But as the proportions of lines depend on their magnitude only, without regard to their position; and motions and forces are said to be equal or unequal, in any given ratio, without regard to their directions: and in general the proportion of quantities relates to their magnitude only, without determining whether they are to be considered as increments or decrements; so there is no ground to imagine any other proportion of +uand-b, than that of the real magnitudes of the quantities represented by a and b, whether these quantities are, in any particular case, to be added or subtracted.

NEGRO, a name given to a variety of

NEPA, in natural history, water-scorpion, a genus of insects of the order Hemiptera. Snout inflected; antennæ short; wings four, folding cross-wise, coriaceous on the npper part; fore legs cheliform; the other four formed for walking. There are fourteen species in three divisions, riz. A. Antennæ palmate, without a lip. B. Antennæ palmate; lip-short, widely emarginate. C. Lip projecting, rounded. N. linearis, described by Mr. Donovan, has a tail ending in two bristles, as long as the body; thorax of one colour; fore-shanks with a spine in the middle. The body is brown, cylindrical; abdomen red; the eggs are oblong, and armed at one end with two bristles, and are found inclosed in the culm or stem of rushes, with hairs standing out.

NEPENTHES, in botany, a genus of the Dioecia Syngenesia class and order. Essential character: calyx four-parted; corolla none: male, filament one, with many anthers, connected into a peltate head: female, style none; stigma large, peltate four-lobed; capsule four-celled, with many arilled seeds. There is but one species, viz. N. distillatoria, a native of the island of Ceylon.

The nepenthes may justly be classed among the most singular productions of the vegetable world. The plant has always excited the admiration of those who have examined its structure, with a view to the contrivance which is so strikingly exhibited in the formation of its leaves. The nepenthes is a native of India: it is an herbaceous plant, with thick roots and a simple stem, crowned with flowers disposed in bunches. The leaves are alternate, partly embracing the stem at their base, and terminated by tendrils, each of which supports a deep, membranous urn, of an oblong shape, and closed by a little valve like the lid of a box. This appendage to the leaf appears to be as designed and studied a piece of mechanism as any thing we can meet with in nature's more complicated productions. The leaf, as we have already said, is terminated by a deep oblong urn; this, in general, is filled with a sweet limpid water. In the morning, the lid is closed, but it opens during the heat of the day, and a portion of the water evaporates; this is replenished in the night, and each morning the vessel is full, and the lid shut. The

plant grows in a climate where the parch ed traveller is frequently in want of refreshment, and gladly avails himself of the water which this vegetable affords, each urn containing about the measure of half a wineglass. The use of this plant is too evident to need any comment. It is one of the many instances in nature of the bounty of Providence, who has filled the urns of the nepenthes with a treasure, of all others the most refreshing to the inhabitants of hot climates.

NEPER or NAPIER (JOHN), in biography, Baron of Marchiston, in Scotland, inventor of the logarithms, was the eldest son of Sir Archibald Napier, of Marchiston, and born in the year 1550. Having given early indications of great natural parts, his father was careful to have them cultivated by a liberal education. After going through the ordinary course of education at the university of St. Andrew's, he made the tour of France, Italy, and Germany. On his return to his native conntry, his literature and other fine accomplishments soon rendered him conspicuous; he, however, retired from the world to pursue literary researches, in which he made an uncommon progress, as appears by the several useful discoveries with which he afterwards favoured mankind. He chiefly applied himself to the study of mathematics, without, however, neglecting that of the Scriptures; in both of which he discovered a very extensive knowledge, and profound penetration. His "Essay upon the Book of the Apocalypse" indicates the most acute investigation; though time has discovered, that his calculations concerning particular events had proceeded from fallacious data. But what has chiefly rendered his name famous was his great and fortunate discovery of logarithms in trigonometry, by which the ease and expedition in calculation have so wonderfully assisted the science of astronomy, and the arts of practical geometry and navigation. Napier, having a great attachment to astronomy and spherical trigonometry, had occasion to make many numeral calculations of such triangles, with sines, tangents, &c.; and these being expressed in large numbers, they hence occasioned a great deal of labour and trouble: to spare themselves part of this trouble, Napier, and other authors about his time, set themselves to find out certain short modes of calculation, as is evident from many of their writings. To this necessity, and these endeavours it is, that we owe several ingenious

contrivances, particularly the computation by Napier's rods, and several other curious and short methods that are given in his "Rabdologia;" and, at length, after trials of many other means, the most complete one of logarithms, in the actual construc tion of a large table of numbers in arithme. tical progression, adapted to a set of as many others in geometrical progression. The property of such numbers had been long known, viz. that the addition of the former answered to the multiplication of the latter, &c.; but it wanted the necessity of such very troublesome calculations as those above mentioned, joined to an ar dent disposition, to realize the use of that property. Perhaps, also, this disposition was urged into action by certain attempts of this kind, which, it seems, were made elsewhere; such as the following, related by Wood, in his "Athenæ Oxoniensis," under the article Briggs, on the authority of Oughtred and Wingate, viz. “That one Dr. Craig, a Scotchman, coming out of Den. mark into his own country, called upon John Neper, baron of Merchiston, near Edinburgh, and told him, among other discourses, of a new invention in Denmark, (by Longomontanus, as 'tis said), to save the tedious multiplication and division in astronomical calculations. Neper, being solicitous to know further of him concerning this matter, he could give no other account of it, than that it was by proportionable numbers; which hint Neper taking, he desired him, at his return, to call upon him again: Craig, after some weeks had passed, did so, and Neper then showed him a rude draught of that he called Canon Mirabilis Logarithmorum ; which draught, with some alterations, he printed in 1614; it came forthwith into the hands of our author, Briggs, and into those of William Oughtred, from wliom the relation of this matter came."

Whatever might be the inducement, however, Napier published his invention in 1614, under the title of "Logarithmorum Canonis Descriptio," &c. containing the construction and canon of his logarithms, which are those of the kind that is called hyperbolic. This work coming presently to the hands of Mr. Briggs, then Professor of Geometry at Gresham College, in London, he immediately gave it the greatest encouragement, teaching the nature of the logarithms in his public lectures, and at the same time recommending a change in the scale of them, by which they might be ad

vantageously altered to the kind which he afterwards computed himself, which are thence called Brigg's logarithms, and are those now in common use. Mr. Briggs also presently wrote to Lord Napier upon this proposed change, and made journeys to Scotland the two following years, to visit Napier, and consult him about that alteration, before he set about making it. Briggs, in a letter to Archbishop Usher, March 10th, 1615, writes thus: "Napier, Lord of Merchiston, hath set my head and hands at work with his new and admirable logarithms. I hope to see him this summer, if it please God; for I never saw a book which pleased me better, and made me more wonder." Briggs accordingly made him the visit, and staid a month with him.

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The following passage from the life of Lilly the astrologer, contains a curious account of the meeting of those two illus trious men. "I will acquaint you (says Lilly) with one memorable story, related unto me by John Marr, an excellent mathematician and geometrician, whom I conceive you remember. He was servant to King James and Charles I. At first when the Lord Napier, or Merchiston, made public his logarithms, Mr. Briggs, then reader of the astronomy lectures at Gresham College in London, was so surprised with admiration of them, that he could have no quietness in himself until he had seen that noble person the Lord Merchiston, whose only invention they were: he acquaints John Marr herewith, who went into Scotland before Mr. Briggs, purposely to be there when these two so learned persons should meet. Mr. Briggs appointed a certain day when to meet at Edinburgh; but failing thereof, the Lord Napier was doubt ful he would not come. It happened one day, as John Marr and the Lord Napier were speaking of Mr. Briggs; Ah, John, (said Merchiston) Mr. Briggs will not now come.' At the very instant one knocks at the gate; John Marr hastened down, and it proved John Briggs, to his great content. ment. He brings Mr. Briggs up into my Lord's chamber, where almost one quarter of an hour was spent each beholding the other almost with admiration before one word was spoke. At last Mr. Briggs began: My Lord, I have undertaken this long journey purposely to see your person, and to know by what engine of wit or ingenuity you came first to think of this most excellent help into astronomy, viz. the lo

garithms; but, my Lord, being by yon found out, I wonder nobody else found it out before, when now known it is so easy.' He was nobly entertained by the Lord Napier; and every summer after that, during the Lord's being alive, this venerable man, Mr. Briggs, went purposely into Scotland to visit him."

ments in spherical trigonometry, &c. partiNapier made also considerable improvecularly by his "Catholic, or Universal Rule," being a general theorem by which he resolves all the cases of right-angled spherical triangles, in a manner very simple and easy calls the five circular parts. His constructo be remembered; namely, by what hẹ tion of logarithms too, beside the labour of them, manifests the greatest ingenuity. Napier, which were published in the year Kepler dedicated his "Ephemerides" to in his letter, about this time, that he ac1617; and it appears from many passages counted Napier to be the greatest man of his age, in the particular department to which he applied his abilities.

person, was the publication of his “RabdoThe last literary exertion of this eminent logy and Promptuary," in the year 1617, 3d of April, in the same year, in the sixtysoon after which he died at Merchiston, the eighth year of his age. The list of his works is as follows:

1. A Plain Discovery of the Revelation of St. John; 1593.

2. Logarithmorum Canonis Descriptio;

1614.

3. Mirifici Logarithmorum Canonis Con-
structio; et eorum ad Naturales ipsorum
numeros habitudines; una cum appendice,
speciæ, condenda. Quibus accessere pro-
de alia eaque præstantiore Logarithmorum
positiones ad triangula sphærica faciliore
bus aliquot doctissimi D. Henrici Briggii in
calculo resolvenda. Una cum Annotationi-
eas, et memoratam appendicem. Publish-
ed by the Author's son, in 1619.

Virgulas, libri duo; 1617. This contains
4. Rabdologia, seu Numerationis per
rods; with several other short and inge-
the description and use of the bones or
nious modes of calculation.

5. His Letter to Anthony Bacon, (the
original of which is in the Archbishop's Li-
tions, profitable and necessary in these days
brary at Lambeth), intitled Secret Inven-
for the defence of this island, and with-
standing strangers, enemies to God's truth
and religion; dated June 2, 1596.

NEPER'S rods, or bones, an instrument in

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