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the
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s pot where they were' employed ; and he observes,8 re atest of them, especially, is not an entire heap of
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1 a'tont f 168 ’ ^ ecause that portion of it which lies below thef 4 ® an • Sect ' on °f the entrance, may probably be no more0 UOi} e( j Incrustation of the natural rock on which it is-8ta n<l a q'. Mr. Bryant conjectures that, like the sphynx, which!? >t Qens e rect ^y in the front of the second pyramid, they wereHt t| Je ^ c ks which stood upon the brow of the mountain ;° t0|) <sht .j'Syptians cased them over with large stones, and^ Pro 16 ®’ hy these means, to a degree of symmetry^hne Cesg P° rt i°n. At the same time, they filled up thei 1 interstices with rubbish and mortar, and made“V e , r ? and
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1 apartments, as the intervals in the rock allowed,
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’ged to humour the indirect turns and openings in.“‘era a mass, to execute what they proposed. This heth ia aCs° ni i.^ e narrowness an d unnecessary sloping of thew ®ich are often very close and steep, and also fromJ>at n,. °f the rooms in a work of so immense a structure.Pyramids were built upon a rock, in the place
Hooke.
They are six in number, each 25 feetfeet wide. The height of one in the group
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Sfe ^ t'j’iamias were built upon
H Th e y now stand, was suggested by Mr. AiWIWl ■
^bpf^^amids of Saccara, which are as many as 20 in
jj Hh g ar y in form, dimensions, and construction. They
ho?°ar a _ miles to the north and south of the village of
lilt l* 3 c 0IDe t ' lem are rounded at the top, and resemble
Ijj ®, that Ti w ‘d 1 stone. One is constructed with steps,
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c ®igh a? ' /another, built also in steps, is supposed to be<, f >o 3e ,j t ''at of Cheops. The stones whereof they arefor *eh if 6 muc h decayed, and more crumbling than those0 ’j en ce they are considered older. One of them isstr^'’ >Urnt bricks, containing shells, gravel, and
^j t(i 'ds, n ^ ra ! ^°pinion, with regard to the intention and use ofiko? Par'ti P ’, at ^ey were sepulchres and monuments of theh p r Us, c?'/ r \y °f kings. This is expressly affirmed byan< * Strabo (lib. xvii.) ; and the opinions a y, the writings of the Arabians . And the, - o p rea ves, of their erecting these magnificent
funded on the theology of the Egyptians, who,^Pui H dp 0 "^’' n Comment upon Virgil (Aineid, lib. iii.)
Co Sc , ri ' 3es the funeral of Polydorus —AnimamqueCM so ] M — believed, that as long as the bodyHr °pini° n “ t ^ le sou l continued with it; and this wasHo W* °.f the Stoics . The reason of their buildingl ®at th^ S * n t ^ le f° rm °f pyramids, was either from ac ausp t i 13 Wa s the most permanent form of structure,N ’Parti C|J , e T hereby intended to represent some of theirSb.'H tn„. ar y as Greaves conjectures, Osiris, or
o man aa greaves conjectures, vjsins, or me
"‘'sb' '''ere f ra T 3 5 for, under this form, the statues ofAjHPfid. re< iuently exhibited, and the gods themselves
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of j &yptians, the pyramid is said to have beeny the k* an 5 the beginning of which is repre-ss tl a8e ’ an< f the end by the apex; on whichat they used to erect them on sepulchres.
the
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The tomb of Porsenna, king of Etruria , at Clusium inItaly , is an ancient monument of square stone, each side ofwhich is 300 feet broad, and 50 feet high. Within thesquare base, says Pliny , quoting from Yarro, there is aninextricable labyrinth ; upon this square stand five pyramids,four in the angles, and one in the middle, 75 feet broad atthe bottom, and 150 feet high, and terminating in a point;at top, they are covered with a brass circle, from whichare suspended bells, which are put in motion by the wind,so that their sound may be heard at a great distance. Uponthis circle are four other pyramids, each 100 feet high ;above which, upon one plane, are five other pyramids.
Pyramids are found in various parts of the world;indeed, the form of structure seems to have been not un-common. Pyramidal tombs are found in Abyssinia, andeven in Mexico , and the same form is observable in theconstructed temples and pagodas of India and China . SeeEgyptian and Mexican Architecture.
Pyramid, Properties of the. 1. All pyramids and conesstanding on the same base, and having the same altitude, aredemonstrated to be equal.
2. A triangular pyramid is the third part of a prism,standing on the same base, and of the same altitude.
3. Hence, since every multangular may be divided intotriangulars, every pyramid is the third part of a prism,standing on the same basis, and of the same altitude.
4. If a pyramid be cut by a plane parallel to its base, thesection wilLbe similar to the base.
5. All pyramids, prisms, cylinders, &c., are in a ratiocompounded of their bases and altitudes: the bases, there-fore, being equal, they are in proportion to their altitudes;and the altitudes being equal, they are in proportion totheir bases.
6. Similar pyramids, prisms, cylinders, cones, &c., are ina triplicate ratio of their homologous sides.
7. Equal pyramids, &c., reciprocate their bases and alti-tudes : i. e. the altitude of the one is to that of the other,as the base of one is to the base of the other.
8. A sphere is equal to a pyramid whose base is equal tothe surface, and its height to the radius of the sphere.
Pyramid, to measure the surface and solidity of a: Findthe solidity of a prism that has the same base and heightwith the given pyramid: divide this by three; and thequotient will be the solidity of the pyramid. Or, multiplythe base by the perpendicular height; and one-third of theproduct will be the content.
The surface of a pyramid is obtained, by finding the areasof the base and of the lateral triangles. The sum of theseis the area of the pyramid. The external surface of a rightpyramid, standing on a regular polygonal base, is equal tothe altitude of one of the triangles which compose it,multiplied by the circumference of the base of the pyramid.
Pyramid, Frustum of a. See Frustum.
Pyramid, Truncated. See Truncated.
PYRAMIDOID, a solid generated by the revolution ofa pyramid about its base-
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