Seite - 162 - in The Power of Urban Water - Studies in premodern urbanism

162 SophieBouffier urban function.We can just suggest that itwas able to supply themainlandquarters ofAchra- dineandTyche. Theaqueduct Tremilia The third aqueduct, Tremilia, is offset relative to the other twoand is not directed towards the ancient city, which raises several questions about the topography of Syracuse, and the alloca- tionandfunctionof thishydraulicequipment. It isknownoveradistanceofmorethan800m.24 Installed in thewesternpart of the Syracusanplateau, it also adopts anorth/southorientation andhasvertical inspectionshaftswithadepthvarying from14mtoabout34m,25which follow oneanotherat approximately 38mintervals. The inspectionshafts areenclosed in strongslabs of limestone. The angle of its slope poses a problem, because fromwhat Cavallari andHolm had determined, the slope would be only 0.03%, whichwould cause big flow problems.We can note the incongruity of the direction of the aqueduct, that travels outside of the plateau and down to the plain of Syracuse, where no habitat has been identified so far. It is unlikely that itwasused for irrigationof theplateau, as I have suggested in thepast,26 since its excep- tional depth was difficult to reach from the surface andwe do not know of an example of a similar irrigationtechniqueinaSicilianenvironment.However,weshouldquestionthepossible presence of a suburban neighbourhood such as archaeological research has begun to identify in someancient cities of Sicily.27 A technological andstylistic relationship The similarity of the three aqueducts was revealed from the first field studies.28 They exploit the slope of the Epipolai plateau towards the south inmore or less the same direction, feed fromthedepthsof the limestone layer,at the junctionof theclaysubstrate,havenowaterproof- ing coating, thus allowing the percolation ofwater through the rock. The typology of galleries is approximately rectangular and has variable dimensions that allow,most of the time, for a man to stand upright, but recent research has also highlighted in the Tremilia Aqueduct, ex- tremely reduced galleries and different depths that show, it seems, digging and fitting errors, madenecessaryby theneed to ensure the smooth flowofwater. Adoublegallery Moreover, the first publications had highlighted the presence of a double gallery: ‘Questi tre acquedotti offrono laparticolarità di avere ognunoduegallerie, una sovrapposta all’altra e sul medesimo asse […] La galleria superiore (specialmente quella dell’acquedotto del Paradiso) è profondametri 23circasotto ilpianodicampagna,epocodistantedall’altraovescorre l’acqua: 24 Cavallari–Holm1883, 123f. Itwas recently investigatedby theSyracusanspeleologistgroup:Arenaetal. 2018, 9–13. 25 But these dimensions are based on the current level of the inspection shaft and not on the original part.We must therefore take intoaccountacertain thicknessof sediments impossible toevaluatewithoutanarchaeological dig. 26 Bouffier 1987, 685. 27 AboutHimera,Vassallo 2005, 66. 28 Schubring 1865; Cavallari –Holm1883, 127f.