The Tomb under the Ancient Empire. 2 I Two walls of fine limestone blocks inclose a fillins;- in of rubble, to which they are bound by perpend stones which penetrate its substance. This method of construction has its faults, but it is so rapid that its employment is not to be wondered at. JJ ZO JO *o So Fig. 143.— Section of the Stepped Pyramid at Sakkarah ; from Lepsius.^ Do these parallel walls reach from top to bottom ? A detail discovered by Minutoli would seem to indicate that a base was first constructed of sufficient extent for the whole monument. In the lower part of the Stepped Pyramid Minutoli"^ shows concave Fig, 144. — Construction of the Pyramid of Abousir in parallel layers; transverse section in perspective from the geometrical section of Lepsius.^ courses of stone laid out to the segment of a circle. These courses formed a kind of inverted vault, abutting, at its edges, upon ^ Fig. 5 of his paper, Ueber den Ban der Pyramiden. 2 Voyage an Temple de Jupiter Ammo7i et dans la Haute- Egyte. (Berlin, 1824, 4to. and folio; pi. xxvii. fig. 3.) 3 Fig. 8 of his paper, Ueber den Ban der Pyramiden.