372

HISTORY OF ENGINEERING.

Book I.

first course there were altogether 4 stones, in the second 13, in the third 25, in thefourth 23, in the fifth 26, and in the sixth 26; these six courses brought the platform up

IE

Fig. 374.

FIRST COURSE OF UASONRY,

level with the top of the rock, and the laying of these 123 stones occupied 61 days; thewhole were of moorstone, and cemented together with lime and puzzolana.

E

Fig. 375.

SECOND COURSE OF MASONRY.