70 History of Art in Antiquity. the horizontality of its courses. Tlie units, fixed without mortar, reach sometimes 4 m. 20 c. in length and nearly 1 m. in height. They were united by iron clamps " dipped in lead," or dove- tails* (Fig. 18). The metal has disappeared almost everywhere, torn off by the pilfering hands that have been so actively busy among these ruins; but the sealing marks left in the stone are Still visible. The works undertaken on this site were no doubt interrupted by the death of the prince for whom they were made, so that the face of the wall was left in a semi-rude state. But wherever it was completed each block is surrounded by a narrow groove cut to a sharp edge. On the con- trary, where it was unfinished — in the upper part of the illustration (Fig. 18), for example —we find a double chiselling, the inner face serving but as a mark to guide the mason how to complete the work begun in the stone-yard when the units should be set up in place. There was a good reason for allow- ing the bossed*' state of the stones to subsist until the wall was finbhed, since its relief would serve to protect the faces that were to be apparent, and would screen them against accidents and rude contact whilst the work was in progress. There is no sign of cement about the core laid out in horizontal beds, which were carried up to the level of the slabs at the sides. The internal facing is vertical, but a certain amount of footing was given to the base by setting the lower courses slightly back from each other as they rose upwards, a practice of which examples abound in the constructions of the East and those of Greece.* The same constructive method was followed in setting up the platform at Persepolis. It consists of a double retaining wall. The first, next to the platform, is built of limestone blocks of I enormous size, which were united together with metal damps * . without any sign or token of cement ; the second is likewise un-
- Rick, Namtwe of a Journey to Ptnepoiis^ x8>9» 3vo, p. 243.
The damps were iron or lead," Wjrs Ridi, to whom Penot lefers.— Trs.
- DijvULAFov, LArt antique, etc, tom. i. i)p. 6 -10. Many of the blocks in
question bear inasoDs' marks, of which a number are fibred, pp. 11 and 12 of the above work.
- Rich, A^rnUlffv, p. 353.
Fir. fS.— Groom for re* ceiving cluvc-taih. n.iii and scctiun. UlEULA- FOY. UAri antifttttVanL, i. Fig. 16. Digitized by Google
