parabolicpyramidoid

A solid generated by supposing all the squares of the ordinates applica 'ble to the parabola so placed that the axis shall pa through all their centers at right angles, in which case the aggregate of the planes will form the solid called the parabolic pyramidoid, the solidity of which is equal to the product of the bases and half the altitude. parabolic-reflector, s. A cone of gla with a paraboloidal depre ion which concentrates the rays an object placed in focusinatinal dismounted on an axial pin forms a dark background behind the semi-translucent object, which is illuminated by an annular pencil of rays pa ing around the edge of the disk. parabolic-spindle, subst . A solid generated by revolving a portion of a parabola, limited by a straight line perpendicular to the axis of the curve, about that line as an axis. The volume of a para bolic spindle is equivalent to ff of its circumscribed cylinder. parabolic-spiral, subst . A curve whose polar equation is u2 = 2pt , in which u denotes the radius vector of any point, and t the corresponding angle. păr-a-bol-ic-al, a. [Eng. parabolic ; -al .] 1. Ord . Lang .: Of or pertaining to a parable; of the nature of a parable; allegorical, figurative. 2. Geom .: [PARABOLIC, 2.] păr-a-bol-ic-al-ly, adv. [English parabolical; -ly.] 1. Ord. Lang. In a parabolic manner; in manner of a parable; allegorically. 2. Geom.: In manner or form of a parabola. păr-a-bol-i-form, a. [Eng. parabola, and form.) Having the form of a parabola. ( Harris: Math. Dict.) pa-răb-ô-li-na, 8. [PARABOLA.] Palæont .: A genus of Paradox ide, containing Trilobites (Oleni) with only twelve body rings. It is wholly Upper Cam brian. [OLENUS.] *pa-rab-o-lism, s. [English parabol ( a ); -ism . ] Alg .: The division of the terms of an equation by a known quantity that is involved or multiplied in the first term. ( Bailey .) pa-rab-o-list, s . [Lat. parabola =a parable; Eng. suff. -ist .] A writer or narrator of parables. pa-răb-8-16id, s. [Eng., ., parabol ( a ); -oid ; Fr. para bolo ide .] Geom.: A volume bounded by a surface of the second order, such that sections made by planes pa ed in certain directions are common parabolas. It is a characteristic property of paraboloids that they have no centers except in the extreme cases, when they have an infinite number of centers. There are three varieties of paraboloids, elliptical, hyperbolic, and parabolic. păr-a-bo-161d-al, a. [Eng. paraboloid; -al.] Pertaining to or resembling a paraboloid. păr-a-brom-a-lide, s. [Pref. para-; Eng. bro IMG:content-0630.png:[blocks in formation] IMG:content-0631.png:[blocks in formation]