He then followed it out to the end of the work, without increasing or reducing the scale (Note 17).
[Illustration: Fig.

136 .-- Section of the Great Pyramid.[30]] The pyramids were supposed to have their four faces to the four cardinal points, like the mastabas; but, either from bad management or neglect, the greater part are not oriented exactly, and many vary distinctly from the true north (Note 18).

Without speaking of the ruins of Abu Roash or Zowyet el Aryan, which have not been studied closely enough, they naturally form six groups, distributed from north to south on the border of the Libyan plateau, from Gizeh to the Fayum, by Abusir, Sakkarah, Dahshur, and Lisht.
The Gizeh group contains nine, including those of Khufu, Khafra, and Menkara, which were anciently reckoned among the wonders of the world.

The ground on which the pyramid of Khufu stands was very irregular at the time of construction.

A small rocky height which rose above the surface was roughly cut (fig.