These observations furnish us with an initial objection to the theory to which we have referred. Some may refuse to believe that Cheops intended from the beginning that his pyramid should have the dimensions and the internal arrangements which we now see. But why should he not have done so? If he had died at the end of a few years, his pyramid would, perhaps, have presented to us a shape like that of some other edifices of the same kind, a large base which had never received either its cope-stone or its casing. So too with those of Mycerinus and Chephren. Have not absolute monarchs existed at all times, whose infinite power seems to have made them forget the eternal limits of time and space? Sometimes Fortune has been cruel to them: but often she seems to have placed herself entirely at their disposal. Among the causes which combine to make the royal tombs of the first six dynasties so unequal in height and appearance, the very unequal length of the reigns is the most important. If we were better acquainted with the condition of Egypt in those remote epochs, we should, no doubt, be enabled to give other reasons for their want of uniformity. The chances of completion and even of preservation in its complete state enjoyed by a pyramid must have greatly depended upon the descent of the crown. When king succeeded king in one family those chances were much better than when dynasty succeeded dynasty, whether the break were due to internal revolution or to the failure of the legitimate line. It is even possible that some of those pyramids which are now to outward appearance mere heaps of _débris_ never received the mummy for whose reception they were designed and built. The pyramids differ also in the materials employed. The great pyramids at Gizeh are built of fine limestone from Mokattam and Toura; the chief one at Sakkarah of a bad clayish limestone from the neighbouring rocks; at Dashour and Abou-Roash there are pyramids of unburnt brick. Finally there are pyramids built chiefly of stone which is kept in place by a carefully constructed skeleton, so to speak, of brick. This construction is to be found in the pyramid of Illahoun, at the entrance to the Fayoum (Fig. 131).