136), but at the level of the eighteenth course, at about forty- five feet from the ground. When the block which closed it was displaced, an inclined passage, 41.2 inches wide and 47.6 inches high, was revealed, the lower part of which was cut in the rock. This descended for 317 feet, passed through an unfinished chamber, and ended sixty feet farther in a blind passage. This would be a first disappointment to the spoilers. If, however, they were not discouraged, but examined the passage with care, they would find in the roof, sixty-two feet distant from the door, a block of granite (Note 22) among the surrounding limestone. It was so hard that the seekers, after having vainly tried to break or remove it, took the course of forcing a way through the softer stone around (Note 23). This obstacle past, they came into an ascending passage which joins the first at an angle of 120° (Note 24), and is divided into two branches. One branch runs horizontally into the centre of the pyramid, and ends in a limestone chamber with pointed roof, which is called, without any good reason, "The Queen's Chamber." The other, continuing upward, changes its form and appearance. It becomes a gallery 148 feet long and 28 feet high, built of Mokattam stone, so polished and finely wrought that it is difficult to put a "needle or even a hair" into the joints (Note 25). The lower courses are vertical; the seven others "corbel" forwards, until at the roof they are only twenty-one inches apart. A fresh obstacle arose at the end of this gallery. The passage which led to the chamber of the sarcophagus was closed by a slab of granite (Note 26); farther on was a small vestibule divided in equal spaces by four portcullises of granite (Note 27), which would need to be broken. The royal sepulchre is a granite chamber with a flat roof, nineteen feet high, thirty-four feet long, and seventeen feet wide. Here are neither figures nor inscriptions; nothing but a granite sarcophagus, lidless and mutilated. Such were the precautions taken against invaders; and the result showed that they were effectual, for the pyramid guarded its deposit during more than four thousand years (Note 28). But the very weight of the materials was a more serious danger. To prevent the sepulchral chamber from being crushed by the three hundred feet of stone which stood over it, five low hollow spaces, one over the other, were left above it. The last is sheltered by a pointed roof, formed of two enormous slabs (Note 29) leaning one against the other. Thanks to this device, the central pressure was thrown almost entirely on the side faces, and the chamber was preserved. None of the stones which cover it have been crushed; none have yielded a fraction since the day when the workmen cemented them into their places (Note 30). [Illustration: Fig. 137.--The Step Pyramid of Sakkarah.]