Chap. IV.

ROMAN.

179

towards a pit sunk in the middle, or like a shallow basin, with acircular hole in the centre, through which might be scoured out allthe accumulations of sand or lime deposited; these holes were simply-closed or secured by a plug, or by a hard stone in the form of thefrustum of a cone.

The arch which supports the triple aqueduct of Julia, Tepula,and Martia shows the last-mentioned water conducted through thelowest channel in the section, and that of Julia in the uppermost:it is situated near the Porta Esquilina, and on it is the followinginscription : —

IMP. CAES. DIVI JULI F. AUGVSTVSPONTIFEX MAXIMVS COS. XI.

TRIBVNIC. POTESTAT. XIX. IMP. XIII.

RIVOS AQVARVM OMXIVM REFECIT.

Underneath is another inscription, showing when it was re- ^paired.

IMP. TITVS CAESAR DIVI F. VESPASIANVS AVGVST. PONTIF. MAX.

TRIBVXICIAE POTESTAT. IX. IMP. XV. CEXS. COS- VII. DESIGN. VIII.

RIVOM AQVAE MARCIAF. VETVSTATE DILAPSVM REFECITET AQVAM QVAE IX VSV ESSE DESIDERAT. REDVX1T.

Three streams, conducted by artificial channels one over theother, and differing in quality, required ‘particular care that theydid not leak one into the other, and that the better should not bedeteriorated by communicating with that which differed from itin salubrity and clearness: we consequently find that the channelfor each is based upon a thick stone, passing into the sides of theaqueduct, which is covered with tiles and a coat of cement with thegreatest care: the only chance of any rupture or crack would arisefrom a settlement of a division of the arcade, which would imme-diately be discovered by the leakage, and would speedily be re-stored. Doors from the outsides admitted the attendants occa-sionally to examine the several conduits; and it was the duty # ofthe supervisors and sub-engineers to report constantly upon theirefficiency and condition.

Viz. 197. SECTION OP AQUEDUCT OP AQUAJl'LIA TEPULA, AND. MARCIA.

Fig. 198. AQUA JULIA, TEPULA, AND MARCIA.

And below this, immediately above the middle arch upon the architrave which sup-ports the cornice, is cut another.

IMP. CAES. M. AURELIUS AXTOXIXUS PIUS FELIX AUG. PARTHIC MAXIM.

BRIT. MAXIMUS POXTIFEX MAXIMUS.

AQUAM MARCIAM VARIIS KASIBUS IMPEDITAM PURGATO FOXTE EXCISIS ET PERFORATISMOXTIBUS RESTITUTA FORMA ADQUISITO ETIAM FOXTE XOVO ANTOXIXIANOIX SACRAM URBEM SUAM PERDUCEXIJAM CURAVIT.