Pyramid

(pir'a-mid.) [From Gr. pyramis. ] (Geom.) A solid body erected on a triangular, square, or polygonal base, and terminating at its upper extremity in a point termed the apex. Its lateral surface consists of three or more plane triangles.- (Archæol.) Certain structures of masonry or brickwork erected by the ancients after the manner of the geometrical form above defined. The true extraction of the term is buried in profound obscurity. The most celebrated monuments of the kind extant are the P. of Egypt, 40 in number, and distributed over a wide tract of country, having Memphis for its centre. The largest of them is that known as the Great Pyramid, said by Hero dot us to have been built by Cheops. It is 480 ft. in height, that is, 43 ft. higher than the cro of St. Peter's Church at Rome, and 136ft. higher than that of St. Paul's, London. It covers more than 13 acres of ground, and, if solid, would contain more than 3,000,000 cubic yards of stone, or, in other words, six times as much as what is contained in Delaware breakwater. It is said that in its building 100,000 men were employed for 20 years. These structures were, it is believed, raised as mausoleums for the Egyptian kings. Similar mounds of masonry, but on a smaller scale, are found in Mexico under the name of Teocalis, and in Hindostan and Java. Pyramid Lake, in Nevada, a large expanse of water inRoop co., covering an area of 420 sq. m., in the midst of which rises a pyramidal rocky island, 600 feet in height, whence its name. [s. 744]