The portcullises which invariably close the entrances of the sepulchral chamber in the pyramids are among the most curious and ingenious of the arrangements of these buildings. Generally they consist of great cubical masses of granite, measuring 8 or 10 ft. each way, and consequently weighing 50 or 60 tons, and even more. These were fitted into chambers prepared during the construction of the building, but raised into the upper parts, and, being lowered after the body was deposited, closed the entrance so effectually that in some instances it has been found necessary either to break them in pieces, or to cut a passage round them, to gain admission to the chambers. They generally slide in grooves in the wall, to which they fit exactly, and altogether show a degree of ingenuity and forethought very remarkable, considering the early age at which they were executed.
In the Second Pyramid one chamber has been discovered partly above-ground, partly cut in the rock. In the Third the chambers are numerous, all excavated in the rock; and from the tunnels that have been driven by explorers through the superstructures of these two, it is very doubtful whether anything is to be found above-ground. It is observable that the measurements of the Third Pyramid are as nearly as possible the exact halves of those of the Second. This cannot have been unintentional.
The exceptional pyramid above alluded to is that of Saccara, shown in the annexed plan and section (Woodcuts Nos. 8 and 9), both to the scale of 100 ft. to 1 in. It is the only pyramid that does not face exactly north and south. It is nearly of the same general dimensions as the Third Pyramid, or that of Mycerinus; but its outline, the disposition of its chambers, and the hieroglyphics found in its interior, all would seem to point it out as an imitation of the old form of mausolea by some king of a far more modern date. Some, however, of the more recent authorities seem inclhied to consider this pyramid as the oldest, instead of the most modern, and to ascribe it to Mnevis, the 4th king of the First dynasty, assuming that the hieroglyphics, etc., were added afterwards. Further research will be required to settle this point. For the present it is sufficient to know that it lies outside the regular series of pyramids, and is of a date either anterior or posterior to them; but most probably the latter.
All the old pyramids do not follow the simple outline of those of Gizeh. That at Dashoor, for instance, rises to half its height with a slope of 54° to the horizon, but is finished at the angle of 45°, giving it a very exceptional appearance; and that of JMeydoon has more the appearance of a tower, its angle being 74° 10'. Two smaller towers rise from its summit, in the manner in which it is supposed Assyrian pyramids were usually constructed. It indeed seems not to have been unusual to build pyramids in stories or stages, each less than the other; though it is possible that in this case it may have been only