The usual construction of pyramids is a mass of masonry composed of horizontal layers of rough-hewn blocks, with a small amount of mortar; and this mass in the later forms became more and more rubbly, until in the VIth Dynasty it was merely a system of retaining walls of rough stones and mud, filled up with loose chips, and in the XIIth Dynasty the bulk was of mud bricks. There was always on the outside a casing of fine stone, elaborately finished, and very well jointed; and the inner cham bers were of similarly good work. Indeed, the construction was in all cases so far sound that, had it not been for the spite of enemies and the greed of later builders, it is probable that every pyramid would have been standing in good order at this day. The casings were of massive blocks, usually greater in thickness than in height. Inside each pyramid, always low down, and usually be low the ground level, was built a sepulchral chamber; this was reached in all cases by a passage from the north, sometimes beginning in the pyramid face, sometimes descending into the rock on which the pyramid was built in front of the north side. This chamber, if not cut in the rock altogether (as in Menkaura's), or a pit in the rock roofed with stone (as in Khafra's), was built between two immense walls which served for the east and west sides, and between which the north and south sides and roofing stood merely in contact, but unbonded. The gable roofing of the chambers was formed by great sloping slabs of stone, projecting from the north and south walls, on which they rested without pressing on each other along the central ridge; thus there was no thrust, though it had been provided for in the sloping form of the roof, so as to delay as long as possible the collapse of the chamber. This is best seen in the pyramid of Pepi (Petrie), opened from the top right through the roof. The roofing is some times of more than one layer; in Pepi's pyramid it is of three layers of stone beams, each deeper than their breadth, resting one on another, the thirty stones weighing more than 3o tons each. In the king's chamber (Gizeh) successive horizontal roofs were interposed between the chamber and the final gable roof, and such may have been the case at Abu Roash (Howard Vyse).
The passages which led into the central chambers have usually some lesser chamber in their course, and are blocked once or oftener with massive stones. In all cases some part, and generally the greater part, of the passages slopes downwards, usually at an angle of about 26°, or i in 2. These passages appear to have been closed externally with stone doors turning on a horizontal pivot, as may be seen at South Dahshur. This suggests that the interiors of the pyramids were accessible to the priests, probably far making offerings.
The pyramid of Medum was the first true pyramid. It was begun as a mastaba. This mastaba was then enlarged by heighten ing it and adding a coating, and this process, repeated seven times, resulted in a high stepped mass of masonry. Such had been made before, at the step pyramid of Saqqara; but for the first time it was now covered with one uniform slope of masonry from base to top, and a pyramid was the result. The chamber is peculiar for being entered by a vertical shaft in the floor. The great pyramid of Gizeh (Khufu's) is very different in its internal arrangements from any other. The pyramid covers upwards of 13 ac. and is about 15o ft. higher than St. Paul's cathedral. The greater number of passages and chambers, the high finish of parts of the work and the accuracy of construction all distinguish it. The chamber which is most normal in its situation is the sub terranean chamber; but this is quite unfinished. The upper
chambers, called the "king's" and "queen's," were completely hidden, the ascending passage to them having been closed by plugging blocks, which concealed the point where it branched upwards out of the roof of the long descending passage. Another passage, which in its turn branches from the ascending passage to the queen's chamber, was also completely blocked up. The object of having two highly-finished chambers in the mass may have been to receive the king and his co-regent (of whom there is some historical evidence) and there is very credible testimony to a sarcophagus having existed in the queen's as well as in the king's chamber. The accuracy of work is such that the four sides of the base have only a mean error of 9- in. in length and 12" in angle from a perfect square.' The second pyramid of Gizeh, that of Khafra, has two separate entrances (one in the side, the other in the pavement) and two chambers (one roofed with slabs, the other all rock-hewn) ; these chambers, however, do not run into the masonry, the whole bulk of which is solid so far as is known. This pyramid has a part of the original casing on the top; and it is also interesting as having the workmen's barracks still remaining at a short distance on the west side, long chambers capable of housing about 4,00o men. The third pyramid, that of Menkaura, was cased around the base with red granite for the 16 lowest courses. Its design has been enlarged at one bound from a small pyramid (such as those of the family of Khufu) to one eight times the size, as it is at present, the passages needed therefore to be altered. But there is no sign of gradual steps of enlargement : the change was sudden. The basalt 'With respect to the construction of this and other pyramids, see Howard Vyse ; on measurements of the inside of the great pyramid and descriptions, see Piazzi Smyth ; and on measurements in general mechanical means, and theories, see Petrie.
sarcophagus of this pyramid was ornamented with the panel decoration found on early tombs, unlike the granite sarcophagi of the two previous pyramids, which are plain. Unhappily it was lost at sea in 1838.
Farther south are the pyramids of Abusir, described in the work of Col. Howard Vyse, and since excavated by the Germans. Next come those of Saqqara. The construction of the step pyramid or cumulative mastaba has been noticed above; its passages are very peculiar and intricate, winding around the principal chamber, which is in the centre, cut in the rock, very high, and with a tomb-chamber built in the bottom of it, which is closed with a great plug of red granite. A doorway faced with glazed tiles bearing the name of King Neter-khet of the IIIrd Dynasty existed here; the tiles were taken to Berlin by Lepsius. Beyond these come the pyramids of Dahshur, which are in a simple and massive style, much like those of Gizeh. The north pyramid of Dahshur has chambers roofed like the gallery in the great pyramid by successive overlappings of stone, the roof rising to a great height, with no less than II projections on each side. The south pyramid of Dahshur has still the greater part of its casing re maining, and is remarkable for being built at two different angles, the lower part being at the usual pyramid angle, while the upper part is but Beyond the Memphitic group are the scattered pyramids of Lisht (Senusert I.), Illahun (Senusert II.) and Howara (Amenemhat III.), and the earliest pyramid of Medum (Sneferu). Illahun is built IA ith a framework of stone filled up with mud bricks, and Howara is built entirely of mud bricks, though cased with fine stone like the other pyramids.