mark nothing precise, and are therefore indefinite.

DEFINITE. S. (from the adjective.) Thing explained or defined (Ayliffe).

DEFINITIVENESS. s. (from definite.) Certainty; limitedness.

DEFINITION. s. (definitio, Latin.) 1. A short description of a thing by its properties (Dryden). 2. Decision; determination.

DEFINITION, in logic, an enumeration of the chief simple ideas of which a compound idea consists; in order to ascertain or to explain its nature and character.

Definitions are of two kinds: the one nominal, or, of the name; the other real, or, of the thing.

Definition of the name, or nominal definition, is that which explains the sense or signification appropriated to a word: or, as Wolfius more accurately considers it, it is an enuineration of certain marks, or characters, sufficient to distinguish the thing defined from any other thing; so as to leave it out of doubt. what the subject is that is intended, or denoted by the name. This is what is meant by de

finition in mathematics.

Such is the definition of a square, when it is said to be a quadrilateral, equilateral, rectangular figure.

By definition of the name, is either meant a declaration of the ideas and characters appropriated to the word in the common usage of the language; or the peculiar ideas, &c. which the speaker thinks fit to denote by that word, i. e. the special sense wherein he proposes to use it, in his future discourse. For it may be observed, that the significancy of any word depends entirely on our will; and we may affix what idea we please to a sound, which it self signifies nothing at all.

The definition of the name, therefore, in the second sense, is merely arbitrary, and ought never to be called in question; only it is to be minded, that we keep inviolably to the same signification. Hence, a definition comes to stand, or to be made use of, as an undoubted or self-evident maxim; as it frequently does, and particularly among geometricians, who, above all other people, make use of such definitions.

Definition of the thing, or real definition, is properly an enumeration of the principal attributes of a thing, in order to convey or explain its nature,

Thus, a circle is defined a figure, whose circumference is every where equidistant from its centre.

Wolfius defines a real definition to be a distinct notion explaining the genesis of a thing; that is, the manner wherein the thing is made, or done such is that of a circle, whereby it is said to be formed by the motion of a right line round a fixed point. On which footing, what was before instanced as a real definition of a circle amounts to no more than a nominal

one.

This notion of a real definition is very strict and just; and affords a sufficient distinction

between a real and nominal one. But though it has the advantages of analogy, distinctness, and conveniency, on its side; yet, being only itself a nominal definition, i. e. a definition of the term real definition, we must consider it in that light, that is, an idea fixed arbitrarily to that word, and which the author always denotes by that word in the course of his book.

Of the parts enumerated in a definition, some are common to other things beside the thing defined; others are peculiar thereto: the first are called the genus, or kind; and the second, the difference. Thus, in the former definition of a circle, by a figure whose circumference is every where equidistant from its center; the word figure is the kind, as being a name common to all other figures, as well as the circle; the rest are the difference, which specify, or distinguish, this figure from every other figure. And hence arises that rule of F. de Colonia, for the making of a definition. "Take," says he, "something that is common to the thing defined with other things, and add to it something that is proper, or peculiar to the thing; i. e. join the genus and specific difference, and you will have a definition."

The special rules for a good definition are these: 1. A definition must be universal, or adequate, that is, it must agree to all the particular species, or individuals that are included under the same idea. 2. It must be proper, and peculiar to the thing defined, and agree to that alone. These two rules being observed, will always render a definition reciprocal with the thing defined, that is, the definition may be used in the place of the thing defined; or they may be mutually affirmed concerning each other. 3. A definition should be clear and plain; and, indeed, it is a general rule concerning the definition both of names and things, that no word should be used in either of them which has any difficulty in it, unless it has been before defined. 4. A definition should be short, so that it must have no tautology in it, nor any words superfluous. 5. Neither the thing defined, nor a mere synony mous name, should make any part of the definition.

DEFINITIVE. a. (definitivus, Lat.) Determinate; positive; express (Wotton). DEFINITIVELY. ad. Positively; deci sively; expressly (Hall).

DEFINITIVENESS. s. Decisiveness. DEFLAGRABILITY. s. (from deflagro, Latin.) Combustibility (Boyle).

DEFLA GRABLE. u. (from deflagro. Latin.) Having the quality of wasting away wholly in fire, without any remains (Boyle).

DEFLAGRATION. (deflagratio, from deflagro, to burn.) Calcination. A chemical term, chiefly employed to express the burning or setting fire to any substance; as nitre, sulphur, &c.

To DEFLECT. v. n. (deflecto, Latin.) To turn aside; to deviate from a true course (Blackmore).

DEFLECTED, in botany; a branch of a tree, bowed, or bending down archwise. DEFLECTION, the turning any thing aside from its former course by some adventi tions or external cause.

The word is often applied to the tendency of a ship from her true course, by reason of currents, &c. which divert her, and turn her out of her right way.

DEFLECTION OF THE RAYS OF LIGHT, is a property which Dr. Hook observed in 1674-5, and read an account of before the Royal Society, March 18, the same year. He says, he found it different both from reflection and refraction; and that it was made towards the surface of the opacous body perpendicularly. This is the same property which sir Isaac Newton calls inflection. It is called by others diffraction.

DEFLECTIVE FORCES (from deflecto, Lat. to bend or turn aside), are those forces which act upon a moving body in a direction different from that of its actual course, in consequence of which the body is deflected, or turned, or drawn aside, from the direction in which it is moving. Such is the attractive force of the sun upon the earth in its orbit.

DEFLEXURE. s. (from deflecto, Latin.) A bending down; a turning aside, or out of

the way.

DEFLORATE, in botany. Having discharged the farina or pollen.

DEFLORATION, or DEFLOWERING, the act of violating or taking away a woman's virginity. (See VIRGINITY.) Death or marriage is decreed by the civil law in case of defloration.

To DEFLOUR. v. a. (deflorer, French.) 1. To ravish; to take away a woman's virginity (Ecclus.). 2. To take away the beauty and grace of any thing (Taylor).

DEFLOURER. 5. (from deflour.) A ravisher; one that takes away virginity (Ad.). DEFLUOUS. a. (defluus, Latin.) 1. That flows down. 2. That falls off.

DEFLUX. s. (defluxus, Latin.) Dowaward flow (Bacon).

DEFLUXION. s. (defluxio, from defuo, to run off.) In medicine, a discharge of a fluid from any part.

DE/FLY. ad. (from deft.) Dextrously; skilfully properly deftly (Spenser).

DEFOE (Daniel), a celebrated English writer, was born, we believe, at Elton, in Huntingdonshire, in the year 1660. He was bred a hosier; which profession, however, he soon forsook, and became one of the most enterprising authors that any age has produced. When discontents ran high at the revolution, and king William was obliged to dismiss his Dutch guards, De Foe, who had true notions of civil liberty, ridiculed the enemies of government in his well-known poem, called The True born Englishman, which had a prodigious sale. The next satire he wrote was entitled Reformation of Manners, aimed at some persons of high rank, who rendered themselves a disgrace to their country. When the

ecclesiastics in power breathed too much of a spirit of persecution, De Foe wrote a tract called The Shortest Way with the Dissenters: for which he was called to account, and explained himself with great firmness. He was afterwards sentenced to the pillory for attack. ing some public measures; which so little intimidated him, that, in defiance of their usage, he wrote A Hymn to the Pillory. It would be endless to enumerate all his publications; but the following are the principal: The History of the Plague in 1665; a novel entitled The History of Colonel Jack; A new Voyage round the World by a Company of Merchants, printed for Bettesworth, 1725; The History of Roxana; Memoirs of a Cavalier; The History of Moll Flanders; The Family Instructor; a book entitled Religious Courtship, which has undergone upwards of 30 editions; and the Life and Adventures of Robinson Crusoe; an admirable performance, of which there have been editions without number, but concerning which there is an anecdote that does the author of it no credit as to the better part of a writer's character, honesty. When captain Woods Rodgers touched at the island of Juan Fernandes, in the South Sea, he brought away Alexander Selkirk, a Scots sailor, who had been left ashore there, and had lived on that desolate place above four years. When Selkirk came back to England, he wrote a narrative of his adventures, and put the papers into the hands of De Foc to digest for publication; who ungenerously converted the materials into the History of Robinson Crusoe, and returned Selkirk his papers again! a fraud for which in a humane view, the disunguished merit of that romance can never atone. For the evidence on which this charge against De Foe stands, see Providence Displayed; or, An Account of the extraordinary Sufferings of Alexander Selkirk, by Mr. Isaac James, of Bristol. Daniel De Foe died at Islington, in 1731. All his productions of the romantic species, but especially the two last mentioned, are much in vogue among country readers; and, on account of their moral and religious tendency, may probably do a great deal of good. Robinson Crusoe is a performance strictly unique, both in the plan and execu tion. Our raises, however, must be confined to the first volume, which, probably, was all he intended publishing, till the second was drawn from him by motives of gain. De Foe also wrote a History of the Scotch Union, a work which does the author considerable credit: a new edition of it was published a few years ago, in 4to. by Chalmers.

DEFOEDA'TION. s. (from defœdus, Lat.) The act of making filthy; pollution (Bent.).

DEFOLIATION, or shedding the leaves. In botany, a term that implies not so much the action of unleaving, or shedding leaves; as the season in which this action is performed.

The following table, respecting the mean times in which the different trees shed their leaves, is founded upon observation:

DEFORCEMENT, in the law of Scotland, is used for resisting, or offering violence to the officers of the law, while they are actually employed in the exercise of their functions, by putting its orders and sentences in execution. The punishment of this crime is confiscation of moveables, joined with some arbitrary punishment, as fine, imprisonment, banishment, or corporal pains, according to the degree of violence, and other circumstances which aggravate the crime.

DEFORCEOR, in law, is a person that overcomes and casts forth another from his lands and tenements by force, and differs from a disseizor on this account: 1. That a man may be disseized without force. 2. A man may deforce another that never was in possession; as where many have a right to lands, as common heirs, and one of them enters and keeps out the rest. A deforceor likewise differs from an intruder, who is made by a wrongful entry only into land, &c. void of a possessor, whilst a deforceor is he that holds out against the right heir.

To DEFORM. v. n. (deformo, Latin.) 1. To disfigure; to make ugly (Shakspeare). 2. To dishonour; to make ungraceful (Dryden), DEFO'RM. a. (deformis, Lat.) Ugly; disfigured; of an irregular form (Milton). DEFORMATION. s. (deformatio, Lat.) A defacing; a disfiguring.

DEFORMEDLY. ad. (from deform.) an ugly manner.

In

DEFO'RMEDNESS. s. (from deformed.) Ugliness; a disagreeable form.

1.

DEFORMITY. s. (deformitas, Lat.) Ugliness illfavouredness (Shakspeare). 2. Ridiculousness (Dryden). 3. Irregularity; inordinateness (K. Charles).

DEFORMITY is immediately opposed to beauty, and denotes the want of that uniformity, symmetry, and variety, necessary to constitute beauty. Accordingly, Dr. Hutcheson

defines it by the absence of beauty, or a deficiency in the beauty expected in any species. Deformity and beauty may be considered either as natural or moral. These are both referred by the above-mentioned ingenious writer to an internal sense; and our perceptions of them, as he supposes, arise from an original, arbitrary structure of our own minds, by which certain objects, when observed, are rendered the occasions of certain sensations and affections.

That many objects give no pleasure to our sense is obvious. Many are certainly void of beauty; but then, says this author, there is no form which seems necessarily disagreeable of itself, when we dread no other evil from it, and compare it with nothing better of the kind. Many objects are naturally displeasing, and distasteful to our external senses, as well as others pleasing, and agreeable; as smells, tastes, and some separate sounds: but with regard to our sense of beauty, no composition of objects which give not unpleasant simple ideas, seems positively unpleasant, or painful of itself, had we never observed any thing better of the same kind.

Had there been a species of the form which we now denominate ugly, or deformed, and had we never seen or expected greater beauty, we should have received no disgust from it; though the pleasure would not have been so great in this form as in those we now admire. Our sense of beauty seems designed to give us positive pleasure; but not positive pain, or disgust, any farther than what arises from disappointment.

The chief cause of the personal deformity so frequent at present, is the neglect of paying proper attention to the clothing of infants, by which they are deprived of the free use of their limbs; and thus, in a great measure, rendered unserviceable to society. But, though deformity may apparently be prejudicial to health, it is ultimately a real advantage. Deformed persons, it is true, possess a less share of strength than others; they should, therefore, be naturally more careful to preserve it, as well as their health; which can be effected only by a strict adherence to temperance. This object will likewise be considerably facilitated by moderate exercise, which few, in such a situation, can want strength to perform; and, as they are not calculated for violent exercise, they are consequently exempt from all the disorders arising from that source; and may thus attain a mature old age.

In the work entitled Fugitive Pieces is preserved an excellent essay on bodily deformity, by the late William Hay, esq, who was himself deformed, and who, while he rallies his own figure with great pleasantry, discusses the general subject in a manner equally instructive and agreeable. He considers the natural con sequences of bodily deformity; how it affects the outward circumstances; and, lastly, what turn it gives to the mind. The reader will find much amusement and information result from consulting this admirable essay.

DEFO'RSOR. s. (from forceur, French.) One that overcomes and casts out by force (Blount).

DEFOSSION, burying alive: this was inflicted by the Romans on vestal virgins guilty of incontinency.

To DEFRAUD. v. a. (defraudo, Latin.) To rob or deprive by wile or trick; to cheat (Pope).

DEFRAUDATION. s. (defraudo, Lat.) Privation by fraud (Brown).

DEFRAUDER. s. (from defraud.) A deceiver; one that cheats (Blackmore).

To DEFRA'Y. v. a. (defrayer, Fr.) To bear the charges of (Bacon). DEFRAYER. s. (from defray.) One that discharges expences.

DEFRA'YMENT. s. (from defray.) The payment of expences.

DEFT. a. (dæft, Saxon.) Obsolete. 1. Neat; handsome; spruce. 2. Proper; fitting (Shakspeare). 3. Ready; dexterous (Dry.). DEFTERDAR, or DEFTARDAR, in the Turkish and Persian polity, an officer of state, answering to our lord treasurer, who appoints deputies in every province.

DEFTLY. ad. (from deft.) Obsolete. 1. Neatly; dexterously (Shakspeare). 2. In a skilful manner (Gay).

DEFUNCT. a. (defunctus, Lat.) Dead; deceased (Hudibras).

DEFUNCT. s. (from the adjective.) One that is deceased; a dead man or woman (Graun!).

DEFUNCTION. s. (from defunct.) Death (Shakspeare).

To DEFŸ', v. a. (deffier, French.) 1. To call to combat; to challenge (Dryden). 2. To treat with contempt; to slight (Shak.).

DEFY'. s. (from the verb.) A challenge; an invitation to fight (Dryden).

DEFYER. s. (from defy.) A challenger; more properly defier (South).

DEGENERACY. s. (from degeneratio, Latin.) 1. Departure from the virtue of our ancestors. 2. Desertion of that which is good (Tillotson). 3. Meanness (Addison).

To DEGENERATE. v. n. (degenerer, French.) 1. To fall from the virtue of our ancestors. 2. To fall from a more noble to a base state (Tillotson). 3. To fall from its kind; to grow wild or base (Bacon).

DEGENERATE. a. (from the verb.) 1. Unlike his ancestors (Swift). 2. Unworthy; base (Millon).

DEGENERATENESS. s. Degeneracy; state of being grown wild, or out of kind.

DEGENERATION. s. (from degenerate.) 1. A deviation from the virtue of one's ancestors. 2. A falling from a more excellent state to one of less worth. 3. The thing changed from its primitive state (Brown).

DEGENEROUS. a. (from degener, Lat.) 1. Degenerated; fallen from virtue. 2. Vile; base; infamous; unworthy (South).

DEGENEROUSLY. ad. In a degenerate manner; basely; meanly (Decay of Piety). DEGLUTITION. s. (deglutition, Fr.) The act or power of swallowing (Arbuthnot).

Deglutition is performed in the first place by means of the tongue, driving the aliment into the oesophagus or gullet, and then, by the contraction of the sphincter, and the fleshy fibres of the oesophagus, which, lessening its aperture, protrude the contents downward into the stomach.

DEGRADATION. s. (degradation, Fr.) 1. Dismission from an office or dignity (Ayliffe). 2. Degeneracy; baseness (South). 3. Diminution of value.

DEGRADATION, a punishment of delinquent ecclesiastics. The canon-law distinguishes it into two sorts: the one summary, by word only: the other solemn, by stripping the person degraded of those ornaments and rights which are the ensigns of his order or degree. The canonists likewise distinguish degradation from deposition; understanding by the latter the depriving a man of his clerical orders, but by the former only the removing him from his rank or degree. In the ancient primitive church, degrading a clergyman was reducing him to the state and communion of laymen. The full import of the phrase, however, is the depriving him of his orders, and reducing him to the simple condition of a layman; a punishment inflicted for several offences, as adultery, theft, or fraud: and clergymen thus reduced were seldom allowed to recover their ancient station, except upon some great necessity or very pressing reason.

To DEGRADE. v. a. (degrader, French.) 1. To put one down from his degree (Shakspeare). 2. To lessen; to diminish the value of (Milton).

DEGREE. s. (degré, French.) 1. Quality; rank; station (Prior). 2. The comparative state and condition in which a thing is (Bac.). 3. A step or preparation to any thing (Sidn.). 4. Order of lineage; descent of family (Dryden). 5. Order or class (Locke). 6. Measure; proportion (Dryden). 7. The vehemence or slackness of the hot or cold quality (South).

DEGREE, in algebra, a term applied to equations, to distinguish the highest power of the unknown quantity. Thus, if the index of that power be 3 or 4, the equation is respectively of the 3d or 4th degree.

DEGREE, in geometry or trigonometry, is the 360th part of the circumference of any circle. Every circle being considered as divided into 360 small near the top of the figure; thus 450 is parts, called degrees; which are marked by a 45 degrees.

The degree is subdivided into 60 smaller parts, called minutes, meaning first minutes; the minute into 60 others, called seconds; the second into 60 thirds; &c. Thus 45° 12′ 20′′ are 45 degrees, 12 minutes, 20 seconds.

The magnitude or quantity of angles is accounted in degrees; for because of the uniform curvature of a circle in all its parts, equal angles similar arcs in peripheries of different diameters; at the centre are subtended by equal arcs, and by and an angle is said to be of so many degrees, as are contained in the arc of any circle comprehended between the legs of the angle, and having the angular point for its centre. Thus we say an angle of 90°, or of 45° 24'. It is also usual to

say, such a star is elevated so many degrees above the horizon, or declines so many degrees from the equator; or such a town is situate so many degrees of latitude or longitude. A sign of the ecliptic or zodiac contains 30 degrees.

DEGREE OF LATITUDE, is the space or distance on the meridian through which an observer must move, to vary his latitude by one degree, or to increase or diminish the distance of a star from the zenith by one degree; and which, on the supposition of the perfect sphericity of the earth, is the 560th part of the meridian.

The quantity of a degree of a meridian, or other great circle, on the surface of the earth, is various ly determined by different observers: and the methods made use of are also various.

Eratosthenes, 250 years before Christ, first determined the magnitude of a degree of the meridian, between Alexandria and Syene on the borders of Ethiopia, by measuring the distance between those places, and comparing it with the difference of a star's zenith distances at those places; and found it to be 6943 stadia.

Ptolemy fixes the degree at 661 Arabic miles, counting stadia to a mile. The Arabs themselves, who made a computation of the diameter of the earth, by measuring the distance of two places under the same meridian, in the plains of Sennar, by order of Almamon, make it only 55 miles. Kepler, determining the diameter of the earth by the distance of two mountains, makes a degree 13 German miles; but his method is far from being accurate. Snell, seeking the diameter of the earth from the distance between two parallels of the equator, finds the quantity of a degree,

by one method 57064 Paris toises, or 342354 ft.; by another meth. 57057 .... toises, or 342342 ft.

Since the time of Snell, a degree of latitude has been measured in different places, by various mathematicians: as our limits will not allow of our indulging in a complete historical detail, we shall present our readers with a comparative table of results, and then subjoin a few remarks and eferences.

as those of colonel Mudge.

From a comparison of the measures of a degree on the meridian, at different parts of the earth, it follows that the earth is not strictly spherical, but more nearly agrees in figure with an oblate spheroid; or in the opinion of some, the segments of two rather anequal spheroids are united a the equator, See EARTH and ELLIPTI

CITY.

The great trigonometrical survey of this kingdom, originated puncipally from a memorial of M. Cassini de Thury, transmitted by the French anıbassador to Mr. Fox, then (1783) secretary of

}

1805.

state, setting forth what benefits astronomy would derive from constructing a series of triangles that should connect trigonometrically the two observatorics of Greenwich and Paris, and thus determine their relative positions, more accurately than it was supposed could be done by astronomical observations. Both nations at that time enjoyed the blessings of peace; and the scientific men of each country readily obtained from their respective governments the assistance and patronage which such an undertaking required. As the work proceeded, the objects and inten