Figure 21 represents the comparative levels and dimensions of Mycerinus, Cephren, and Cheops.

The following peculiarities are noticeable:—That Cheops and Cephren are of equal bases at the level of Cephren's base;—that, at the level of Cheops' base, the latter is only half a cubit larger;—that, from the level of Mycerinus' base, Cheops is just double the height of Mycerinus;—and that from the level of Cephren's base, Cephren is just double the height of Mycerinus; measuring in the latter case, however, only up to the level platform at the summit of Cephren, which is said to be about eight feet wide.

The present summit of Cephren is 23·07 cubits above the present summit of Cheops, and the completed apex of Cephren would be 8·21 cubits above the completed apex of Cheops.

In the summit platforms I have been guided by P. Smyth's estimate of height deficient, 363 pyr. inches, for Cheops, and I have taken 8 feet base for Cephren's summit platform.

§ 6. GEOMETRICAL PECULIARITIES OF THE PYRAMIDS.

In any pyramid, the apothem is to half the base as the area of the four sides is to the area of the base.

Thus—Ratio apothem to half base Mycerinus 32 to 20
Thus—Ratio apothem to half base Cephren 33 to 20
Thus—Ratio apothem to half base Cheops 34 to 21
AREA OF THE FOUR SIDES. AREA OF THE BASE.
Mycerinus 70560· 44100
Cephren291060·176400
Cheops330777·90204304

All in R.B. cubits.

Therefore—32 : 20 : : 70560·: 44100
33: 20 : :291060· :176400
34: 21: : 330777·90 :204304