Biquadratic Equation, one in which the unknown quantity rises to the 4th power. Bisection, the division of a quantity into two equal parts. hanging freely from two points of suspension. Catoptrics, that part of Optics which explains the laws and proper ties of light reflected from Specula. Centre of Gravity, that point about which all the parts of a body in any situation exactly balance each other. Characteristic, of a logarithm, the same as Index or Exponent. Chord, a right line, connecting the two extrems of an arc. Circumgyration, the revolving motion of any body about a centre. Coefficients in Algebra, numbers or given quantities usually prefixed to letters or unknowr. quantities, by which they are multiplied. Combinations, the alterations or variations of any number of quan tities, &c. in all possible ways. Commensurable quantities or magnitudes, such as have some com mon aliquot part, or which may be measured or divided without a remainder, by the same measure or divisor. Cominon, applied to an angle, line, measure, or the like, that be longs to two or more figures, &c. Compasses, a Mathematical instrument for describing circles, mea suring and dividing lines, &c. Complement, in general, what is wanting or necessary to complete some certain quantity or thing. Composite number, one that is compounded of, or made up by the multiplication of, two other numbers, greater than 1. Compound quantities, in Algebra, such as are connected together by the sign + or -: Concavily, that side of a figure or body which is hollow. Concentric, having the same centre. Conchoid or Conchiles, the name of a curve, invented by Nico medeg. Concreie numbers, are those that are applied to express, or denote any particular subject, as 3 men, 2 pounds. Concurring or congruent figures, in Geometry, are such as, being laid upon one another, do exactly coincide. Condensation, the compressing or reducing a body into less bulk, or space, whereby it becomes more dense. Cone, a kind of round pyramid, or a solid body having a circle for its base, and its sides formed by right lines drawn from the cir cumference of the base to a point at top, being its vertex. Conic Sections, the figures made by cutting a cone by a plane. Conoid, a figure resembling a coné, except that the slant sides from the base to the vertex are not straight lines, as in the cone, but ourved. Consequent, the latter of the two terms of a ratio. Constant quantities, such as remain invariably the same, while others increase or decrease. Construction, in Geometry, the art or manner of drawing or describ ing figures, the lines of a problem, &c. Contact, Angle of, the opening between a curve line and a tangent to it, particularly the circle and its tangent. Continued Proportion, that in which the consequent of the first ratio is the same with the antecedent of the second, &c. Converging lines, such as continually approximate until they meet. Coverging series, a series of terms that always decrease the further they proceed, or which tend to a certain magnitude or limit. Convex, round or curved and protuberant on the surface. Coordinates, the general term used, when the abscissa and ordinates of a curve are considered corresponding, whether they are at right angles with each other or not. Corollary, a consequence drawn from some proposition or principles already advanced or demonstrated, without the aid of any other proposition. Cubature of a solid, the measuring of the space contained in it, or finding the solid content of it. Cube, a regular solid body, enclosed by six equal sides or faces, which are squares. Curve, a line whose several parts proceed bowing, or tend different ways. Curvilinear Angle, figure, superficies, &c. such as are formed or bounded by curves. Cycloid, a curve, conceived to be described by a point in the cir cumference of a wheel, moving forward in a straight line. Cylinder, a solid having two equal circular ends, and every plane section parallel to the ends, a circle equal to them also. Cylindroid, a solid resembling a cylinder, but differing from it, in having ellipses for its ends or bases. Decagon, a plane geometrical figure of ten sides, and terangles. Declination, the distance of the sun, star, &c. from the Equinoctial, either northward or southward. Liagonal, a right line drawn across a figure, from one angle to another. Diagram, a scheme for the explanation or demonstration of any figure or of its properties. Differential , an indefinitely small quantity, part, or difference, called also an Infinitesimal. Differential method, a method of finding quantities by means of their successive differences. Dimension, the extension of a body considered as measurable, also used with regard to the power of quantities in equations. Diophantine problems, certain questions relating to square and eubic numbers, and to right angled triangles. Dioptrics, that part of Optics, which explains the effects of light as refracted by passing through different mediums. Directrix, a particular right line, perpendicular to the axis of a Conic Section. Dirigent, a term expressing the line of motion, along which a dis cribent line, or surface is carried in the genesis of any plane or solid figure. Disc, the body or face of the sun or moon, such as it appears to us. Divergent or Diverging lines, those whose distance is continually increasing Dodecagon, a regular polygon of twelve equal sides and angles. Duodecimals, a kind of multiplication in Arithinetic by which artifi cers square their dimensions. Duplicate ratio, the square of a ratio, or the ratio of the squares of two quantities. Dynamics, the science of moving powers. Elimination, in Algebra, that operation by which any number n of equations, containing n unknown quantities, are reduced to one equation involving only one unknown quantity. Ellipse or Ellipsis, one of the Conic Sections, popularly called an an oval. Elliptoid, an infinite or indefinite Ellipse. Epicycloid, a curve generated by the revolution of a point of the periphery of a circle, which rolls along or upon the circumference of another circle. Equation, in Algebra, an expression of equality between two dif ferent quantities. Equimultiples, the products of quantities equally multiplied. Excentric, a term applied to such figures, circles, &c. as have not the same centre. Ercess, in Trigonometry, the excess of the sum of the three angles of any spherical triangle, above two right angles. Exponent, the number of quantity expressing the degree or eleva tion of the power. Expression, any Algebraical quantity, simple or compound. Extermination, the taking away of certain unknown quantities from depending equations, so as to have only one equation and one unknown quantity. Factors, a name given to two numbers that are multiplied together. Fluent, the variable quantity, in the doctrine of Fluxions, which is considered as increasing or decreasing. Fluxion, the rate or proportion at which a flowing or varying quan tity eucreases its magnitude or quantity. Fueus, a certain point in the Ellipse, Hyperbola, and Parabola, where the rays reflected from all parts of these curves concur, or meet. Function, an Algebraical expression any how compounded of a cer lain letter or quantity with other quantities or numbers, said to be a function of that letter or quantity. Generating line or figure, that which by any kind of supposed mo tion, may generate or produce some other figure, plane, or solid. Half-Tangents, the tangents of the half arcs. Heptagon, a figure of seven sides and angles. Hexagon, a figure of six sidles and angles. Homologous, in Geometry, applied to the correspondmg sides of similar figures Horopter, in Optics, a right line drawn through the point where the two optic axes meet, parrallel to that which joins the centres of the two eyes or pupils. Hyperbola, one of the Conic Sections, being that, made by a plane cutting a cone, through the base, not parallel to the opposite side. Hypothenuse, in a right angled triangle, the side which subtends, or is opposite to the right angle. Imaginary quantities, in Algebra, the even roots of negative quan tities. Impact, the simple or single action of one body upon another to put it in motion. Incidence or Line of Incidence, the direction or inclination in which one body strikes or acts on another. Inclination, the mutual tendency of two lines, planes, or bodies, towards each other. Inclined plane, a plane inclined to the horizon, or making an angle with it. Incommensurable lines, or quantities, such as have no common measure. Increment, the small increase of a variable quantity. Infinitesimals, certain infinitely or indefinitely small parts, also the method of computing by them. Inscribed Hyperbola, one that lies wholly within the angle of its asymptotes. Interscendent, a term applied to quantities, when the exponents of their power are radical quantities ; as xv2. Intersection, the cutting off one line or plane by another. Isoperimetrical figures, such as have equal perimeters or circum ferences. Lemniscale, the name of a curve in the form of the figure 8. Marimum, the greatest value of a variable quantity. Mulliplicand, one of the two factors in multiplication, being the number to be multiplied. Negative, in Algebra, something maked with the sign Nodes, the two opposite points where the plane of the orbit of a planet intersects the plane of the ecliptic. Nonagon, a figure having nine sides and angles. Oblate, flattened or shortened. Oblique, aslant, indirect, or deviating from the perpendicular. Opaque, not admitting a free passage to the rays of light. Orbit, the path of a planet or comet, being the curve line described by its centre, in its proper motion in the heavens. Ordinates, right lines drawn parallel to each other, and cutting the curve in a certain number of points. Oscillation, the vibration, or the ascent and descent of a pendulum. Osculatory circle, the same as the circle of curvature. Parabola, a figure arising from the section of a cone, by a plane parallel to one of its sides, Parallax, an arc of the heavens intercepted between the true place of a star and its apparent place. Parameter, a certain constant right line, in each of the three conic sections; called also latus rectum. Pentagon, a figure consisting of five sides and angles. Perimeter, the limit, or outer bounds of a plane rectilineal figure. Periphery, the circumference or bounding line of a curvilineal figure. Polygon, a figure of many sides and angles. Polynomial, a quantity consisting of many terms, called a multinomial. Positive quantities, in Algebra, of a real, or additive nature. Prime numbers, those which may only be measured by unity. Prism, a solid, whose two ends are any plane figures, which are parrallel, equal, and similar, and its sides connecting those ends parallelograms. Pyramid, a solid having any plane figure for its base and its sides triangles, whose vertices all meet in a point at the top, called the vertex. Quadratic Equations, those in which the unknown quantity is of two dimensions. Quadralrir, a mechanical line by means of which right lines are found equal to curves. Quindecagon, a plane figure of 15 sides. Radical sign, the sign or character denoting the root of a quantity. Radix or root, a certain finite expression or function, which being evolved or expanded, according to the rules proper to its form, produces a series. Rational, the quality of numbers, fractions, &c. when they can be expressed by common numbers. Reciprocal, the quotient arising by dividing 1, by any number or quantity. Refrangibility of Light, the disposition of the rays to be turned aside. Root, in Arithmetic and Algebra, denotes a quantity, which being multiplied by itself produces some higher power. Series, a rank or progression of quantities or terms, which usually proceed according to some certain law. Spheroid, a solid body approaching to the figure of a sphere with one of its diameters longer than the other. Spiral, a curve line of the circular kind, which, in its progress, re cedes always more and more from a point within called its centre, Terms of a product, of a ratio, &c. the several quantities employed in forming or composing them. Variable, a term applied to such quantities as are considered in a variable or changeable state, either encreasing or decreasing. |