158 HISTORY OF ART IN ANTIQUITY. Acropolis on the southern declivity of Sipylus, near Smyrna (Figs. 12, 13)- Besides the principal gateway* G, there was another entrance, or rather another means of egress, towards the north-east angle of the plateau. Here a flight of twenty-four steps, cut in the depth of the cliff, extend down to the base of rocks bearing the fortress. Two- thirds of the stairway are open to the sky ; the rest is hidden under the vaulted roof and the stones which have fallen from above (A in plan). At the point where the steps break off- (M in plan), there appears a sort of housing, with a groove on either side, six centimetres wide ; which, to judge from a small hole in the roof and the upper floor, must have served to work pulleys, by means of which a portcullis could be let down or hoisted up at will. The underground passage, which from the bottom of the stairway led outside, has the appearance of a natural cavity ; its existence may have suggested the idea of scooping out the steps. It brings to mind the grotto of Aglaurus, at the foot of the Athenian Acropolis, due to a similar slit in the rock, through which the citadel could be entered. 3 As is well known, its discovery by a soldier of Xerxes led to its surrender. To return : the defenders, when sorely pressed, could escape unperceived in the gloom of night by this secret passage, or suddenly fall upon the besiegers. In doing so, however, they ran the risk of the enemy taking possession of the entrance, either by force or through a traitor, and thus have their retreat cut off. Within the citadel they had only to lower the bridge to be safe against surprise. 3 The stairway in the northern face (G in plan) is neither so well preserved, nor does it disappear in the bowels of the earth ; its purpose was simply to bring the threshold of the gateway up to the level of the platform. On the opposite side, towards the south- east angle (L in plan), two internal spurs have been reserved in the stony mass. They are cleanly cut, each with a pair of vertical 1 Width of stairway above, i m. 55 c. ; width below, i m. 300. ; height from the lowermost step to the fortress level, 7 m. 20 c. This leaves a mean altitude of 30 c. for each step. 2 E. BEUL, LAcropole tfAthenes, torn. i. pp. 27, 157. 8 With regard to secret passages, we may remind the reader of that which in Plenum ran under the wall, with outlet into the ditch (Hist, of Art, torn. iy. p. 620, Figs. 304, 308).
