C YL
225
C YZ
c °viriw
"'all ° to be adopted, as it rises from the surface of the8 prit 1(v j lc “ forms a tangent plane to the curvature at thes Priw, ® the arch ; whereas the tangent plane at thea ceiling, which is less than a semi-cylinder,He orms an angle with the plane of the wall, and excites0r| ly <7 7 lameness or imperfection. This kind is thereforec * 5f itl v ^ when the height of the apartment is not suffi-4 g S^eat to admit of a semi-cylindric ceiling.lunettes* 111 'Cylindrical ceiling admits of being pierced by•lie w liich are windows or openings of less height thanI)y tl le ■' n ^ > and consequently form cylindro-cylindric arches,jj 0 lnter section of the curved surfaces.r 'iio s rf ac ?f 0 I cylindrical ceilings are to be found among the» . . 1 Gr« '
‘°et
"■itli,
cecian edifices, but numerous instances are to be
among the Romans, in their small temples and thelarger ones. The ceiling of the templeatiu a ^ UIS ’ ' n ^ le P a l ace °1' Dioclesian , at Spalatro, in^' n drif.»i IS U Welded instance. The proper decorations for
'y ba tl q Ca ^ ceilings are coffers, separated at regular intervals
ai 'e e„ r . . or arc s doubleux, or, as called by some, soffits, whichCv ci.ed with guiUoches _
< ” Yi - i N)) RICAI ‘ ^ oldmn - See Column.a cylincl e RlCAL Faulting, a vault which is the portion of5? etin C rJ‘1 se ? tio c‘ is generally a semicircle, thoughlor want of room, it is a smaller segment. Inl0l ' Zl) ntal | Vau ^' n K> the equilibrium of the arch and the“‘rust of the piers must be attended to.
11 “'I, wl 1 i c ^ ICA ^‘ Walling, is that erected upon a circular
®yii
nd er °f course forms a cylinder, or a portion of a0t| l.v a ’ acc °t'ding as the plan is an entire circumference, or
c yiindf- ment -
JH tnot* 0 ^ Wa ^i n g ‘ s generally estimated at about half as>‘ioTY lum th « price of plain walling; but the price° re “ter a s fi lt: Yo 'lepend upon the diameter, and should be8h CY ^D R T le <llameter is less.
^ a Pe of a CAL Work, any kind of work, partaking of theOo <l, cylinder, of any material, whether stone, brick,
&c.
Dnd
Cv
itDt« . _
i '^nnprv - •>- Nee Joinery.
8| *?l*d of riOlD, (from KvXivSpog, cylinder, and eicog,form)l‘ti ’ ai ' e e UCR P ro P ert y> that a H sections parallel to eitheroff 8 ’ cnlled^tl^ anc * s ‘ rn 'h‘ r ellipses, and that a straight|Pse 8< he axis, will pass through the centre of the
^•lel to .f Xa ^ se ctions of a cylindroid, and every section
Of
r? Ua l len™ *i aect ’°ns of a cylindroid are equi-angular, and
par a u i aA section, are parallelograms or rectangles.
nl i SPOft An o aP n AT,1!nJ« n .‘d „ _.. 1_1
axis.
th^ at i obh Sfl1 to t * ie _
of a *‘s, noo Ue cylinder be cut by a plane perpendicular toVi cl* th e r t0 , eac * 1 en< l> ^ will be cut into three parts,of le Cyli t1 nn . < -‘ , He portion will be a cylindroid
- 4 8 e»^. nar °‘d f. -_ 1.--3 •
''‘OhiTSttient r* u ’ s frequently employed in vaulting, instead
the
a semi-cylinder.
half, where the heightIt is frequently em-
l '6q 1) j n 83 va 1 .y C ° ra P osit ‘ on °i' groins, and where the transverseto kn ln tlleil ' horizontal dimensions, and where it is
^ to k e "* u ‘c lr Horizontal dimensions, and where it is•j i fc v aiib s -6 ^ t ' le an gles of the groin straight, one of theSoli,ij ' s n „ ecessa rily a semi-cylindroid.
S, aet - l y of
‘istaA er ’ hy m Z' a cylindroid is found, as in the prism or
- Ti,h f; (; v u t'plying the area of one of the ends by thew een tho J
Hr sa Pe7fi e - n the ‘wo
tyiiJ'ying content of the curved surface is found bycr. girt by the length of the axis, as in the
°P finding the envelope is the same as that of
3 u
^tbod
a cylinder with an edge, so that when the envelope is lappedround the solid, its edge may coincide with a plane passingthrough three given points.
The method of finding the envelopes of cylinders and cylin-droids, is one of the most useful parts of Stereography, notonly in forming the coverings of bodies, but in forming theangles of all parts of work, where the surfaces of two differentsolids meet each other.
CYMA-RECTA. See Ctmatium.
CYMATIUM, Cima, Cyma, or Sima, (from Kvgariov,undula the diminutive of fcvjua, a wave) a moulding, whose sec-tion is a curve of contrary flexure; it is commonly denominatedby workmen an ogee. This is the strict sense in which theterm ought to be employed, though Vitruvius uses it for anysubordinate moulding which terminates a principal member,and the particular form is specified by prefixing another word,as Doric cymatium, Lesbian cymatium. In the same sense alsohe uses the word Cysis, which signifies separation. Butnotwithstanding this great authority, in the general usageof the term we shall abide by the definition as above,signifying an undulated form, as being most generallyunderstood.
When the concave part of the moulding projects beyondthe convex part, the cymatium is denominated a sima recta ;but when tiie convex part has the greatest projection, thecymatium is denominated a sima-inversa. The sima-recta isotherwise called gida-recta, or doucine, and the sima-inversa,gula-inversa, or talon. Palladio distinguishes the cymatiumof the cornice by the name intavolata. Our architects, inspeaking of the uppermost member of a cornice, call it cima,cyma, or cymatium ; but we see no reason for the word beingappropriated to this situation, as the propriety of terms con-sists in their proper application to definite forms.
The cymatia which are particularized by the terms Tuscan,Doric, and Lesbian, mentioned by Vitruvius , are not definedby this ancient author, and their meaning is only guessed atby his commentators and readers.
The Tuscan is supposed to be an ovolo, or quarter-round ;the Doric, an ovolo, or cavetto; and the Lesbian , the sima-inversa, or talon.
Philander makes two Doric cymatia, one of which, he says,is that said to be Tuscan. The projecture allowed to- theDoric and Lesbian cymatia, is subduple of the height.
CYMBIA, a fillet. See Fillet.
CYPHERING. See Chamfering, which is most in use.
CYZICENE, Triclinium, or Hall, an apartment ofancient Grecian houses, in the porticos, which look towardsthe north.
It is thus explained by Vitruvius , book vi. chap. vi.“ There are some exei, not made in the Italian manner, thesethe Greeks call cyzicenus. They are situated towards thenorth, generally have a view of the garden, and have valvedwindows in the middle. They are of such length andbreadth, that two triclinia, with their surrounding appen-dages, may be placed opposite to each other; they have alsovalved windows on the right and left, that the garden maybe seen through the space of the windows : their height isequal to one and one-half of their breadth.”
The cyzicenus or cyzicena, were of the same use amongthe Greeks, that the triclinia and ceenacula were amongthe Romans.
CYZICUM MARMOR, a species of marble, so called bythe ancients, from the great use made of it by a statuarynamed Cyzicus . It was white, with fine narrow veins ofblack, and was also called proconnessium.