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§ tw 0 s | ' -"O* 1.—The first part of the operation of join-^ >p 0 r; s botb ' n ** ie same ^ at or plane, d A and e gG ' T 3ed to be portions of the flat joining together at
c P^rt ^ eacb Is bent to a right angle, dab and E Gf ;
LW^ou rises upwards, exceeds the part g f, inHj °'2 exi 15 ’ wb * cb * s about one-third.
1, e . Part, G ^ ains the second step of this operation, exhibiting°Tv Z ° n *' F ’ kent over tbe en( l D > perpendicular to the1) 3 '
f so aj t ^ e third step, and shows the part, Dr, No. 2,f^iilent w ° be parallel to the horizon, and consequentlyJ! 8 this o U * tke sur la ce ) c D > °f the upper part ; and, soo. 4 J’^'ation has gone, it is the same as the first.V l ion. l, hits the entire finish or last step of the
p ar e t r rnet hod is by a roll of wood fixed over thesii.o.' 8 w hich descends downwards to cover the slates,
. pj. d in F mre 3, Nos. 1, 2, 3, 4, 5, 6, which aret, l 9Ur es i ain to inspection, from what has been explained
V u Wetp
in Us ed by ’ ^ lumb -Rule, or Plumb-Line , an instru-licjf^hir to ; ^S 130113 ’ carpenters, &c. to draw pei-pendiculars,T>tal , j p e whether walls, &c. be upright, planes
,a t5<eS thelike -
. e 0 £. erive <i from a piece of lead , plumbum, fastened8 0 Inatr ntnent a tkread or chord, which usually constitutes
*O et »m e8 tl
h(: Co l 'nis e ,j le string descends along a ruler of wood orAf* 68 a lePfP^^icolarly on another ; in which case it
P]^ [1 terf* UlIlniet 1® us ed by the pilot to sound the depth
to t^n th e ( ^’. tke wa " which sometimes closes the intervalsWl >cea Pod ium . Umns °f a building. The term is also applieda n e abo^U terve . n ’ n S between two orders of columns
lie*
<i^U8 . Vean »tl.er.°
>0c>„ S. Ill ..
• l|| nber i° r icttino. ^ ort ' dcat ’ on ! a Lind balance used in°inea ev ®rs dcnvn a draw-bridge. They consist of twoAi)<] r '^ctlier i° Ut tw 'ce the length of the bridge they lift,8 nh». ' v s Ct . y °^ lei ' timbers framed in the form of a St.
They are
vpo 8 Cr 0ss 3 ° tnei
!!'- & b y twn'!! UCh , Se ( ve as a counterpoise. --
e a ge's rai VP r, 6^ t jambs, on which they swing ; andthe i or i et down by means of chains joiningand bridge! J °
ab out j>, GARBLE, a sort of marble dug in great1 ? 1^ b es i n y^outh, and in some parts of Devonshire,’ttlf,, “on j a ® r y thick strata, from whence it is carriedke nut|f i^ e . quantities ; and, when wrought, looks
p 0|, n<l Ver y haS 1 tk , an some of the Italian marble.
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Nlv a 13 of and firm, and of a beautiful texture ; itsj.P'de eisa -white, and its variegations are princi-sf’ ^ihl 6 * a Verv nd ' n sma ii er quantities brown and yellow:tli^ 66 ' \&'°W 0 p °’. derl y beds, and there is often a very
is a a ' nt red diffused through the whole sub-’ ° r " ^arknLi.. , -. ,, g . . andig
lr CU UUlllOCU LlllUUgll LUtJ WIlOlO all
i ■ b Of)f> aa Pabl e ab iy even in its whole structure, andto^Ppt) ^ (Lad \ more tban ordinarily elegant polish.
- tot >a ft T a colons? i a c ? nt *nued pedestal, or plinth, servingL is So a . e : it consists of a plinth, base, die, and
tij)
I'Hia ■ M, ts sotnpi- " ‘ “ consists oi a pnntn, Dase, die, andSu ° b p ro ; ln l les ntade to break forward under each
^ 0 Q ie p ro * made to break forward under each
tl^teii Also inn 1011 bein S distinguished by the name ofcClix” Hie le theatre of the ancients, the wall that
(Lorrw? Stra bl otn Lie scene.
^ X) \ lI '0n} n tnu DBCIJC.
V ar ’° Us zvt nciu m, fonaed from pungere , to prick}, aTC iv e.’ 4cci <Fntul
'! late ad 0 p’ ^ term used by the old writers on per-Acciq ent ai t ie - vnn Fhi n g point, adopted by BrookPoints were the vanishing points in the
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horizontal line, and were thus found:—The representationof two original points being obtained, a line was drawnthrough them both, and produced to meet the vanishing lineof the horizon, and the intersecting point was called the acci-dental point, which served to draw all other lines, whoseo.iginals were parallel to the first. The method given byDr. Brook Taylor is, however, much more direct ; as thevanishing point is found by a geometrical process, viz., bydrawing a straight line through the eye, parallel to an originalline, which serves likewise for the vanishing point of all itsparallels.
Point, in geometry, according to Euclid , is a quantitywhich has no parts, or which is indivisible. Wolfius definesit, that which terminates itself on every side ; or which hasno terms or boundaries distinct from itself. This is what weotherwise call the mathematical point, and is only conceivedby the imagination ; yet it is in this that all magnitude beginsand ends, the flux or motion of the point generating a line,that of a line a surface, &c. Hence, some define a point tobe the inceptive of magnitude. Hobbes defines a point tobe a body whose magnitude is not considered ; but his falsenotions of a point, line, and surface, have led him into manyerrors. Monsieur de Crouzas also has supposed a line to becomposed of points, in his Geometry , and in his comment onthe Analyse des Infiniment Petits. One line can cut anotheronly in a point. Any three points being given out of a rightline, a circle, or part of a circle, may be drawn, that shallpass through them all.
Point, in perspective, a term used for various parts, orplaces, with regard to the«perspective plane.
Point, in physics, the smallest or least sensible object ofsight, marked with a pen, point of a compass, or the like.
This is what we popularly call a physical point, which, inreality, has parts, though those parts are not here regarded.Of such points does all physical magnitude consist.
This physical point coincides with what Mr. Locke callsthe point sensible, and which he defines to be the least particleof matter, or space, we can discern. He adds, that, to th9sharpest eye, this is seldom less than thirty seconds of acircle, of which the eye is the centre.
Point, Conjugate, is used for that point into which theconjugate oval, belonging to some kinds of curves, vanishes.
Point, Objective, a point on a geometrical plane, whoserepresentation is required on the perspective plane.
Point of Contkary Flexures, in the higher geometry,the point of a curve wherein it is inflected to a part contraryto that to which it originally tended.
Point of Distance, in perspective, the distance of thepicture, transferred upon the vanishing line from the centre,or from the point where the principal ray meets it ; and thusit is generally understood to be on the vanishing line of thehorizon.
Point of Reflection, in geometry, is commonly usedinstead of point of retrogradation, or retrogression.
Point of Sight, the place of the eye whence the pictureis viewed, according to the definition of Dr. Brook Taylor ;but, according to the old writers on perspective, the point ofsight is what Brook Taylor denominates the centre of thepicture.
Point of View (the same as the point of sight) is thesituation of the eye of the spectator when viewing an objectto be represented in a picture.
POINTED ARCH , an arch pointed at the top, resem-bling the point of a lance. See Architecture.
POINTED ARCHITECTURE, that style of architecturewhich originated in the substitution of the pointed for the