Wkstropp — The Fort of Dun Aengusa in Inishmore, Aran. 13 



run harmlessly for centuries along the smooth faces of the upturned strata, 

 and the fosse died out in the grassy slope above as its diggers left it, unworn, 

 save by " the slow tooth of the sky." At the Black Fort, east from Dun 

 Aengusa, ^ve see that the headland originated from two synclinal curves, the 

 inner arches of which were constantly worked into caves, eventually falling 

 in and leaving long bays.' The destruction of the sides and even of the outer 

 end of the promontory is slow compared with that at the ends of the bays, and 

 the fort between them may be very ancient, though hardly three thousand years 

 old, as O'Donovan fancied. As we noted. Loop Head, the ancient " Leap of 

 Cuchullin" (probably from long before a.d. 850,- when the name first occurs), 

 must have been, in early times as at present, a high rocky islet divided by a 

 narrow chasm from the main cliff, to judge from the name and legend. The 

 only fall of rock recorded at Dun Aengusa for over seventy years is that of 

 a slab from which a man was fishing when it fell in 1837' ; but cliff falls are 

 more usually sudden and at long intervals than persistent and gradual. 



So far we have only dealt with the changes made by the great forces of 

 nature ; now we turn to other evidences of mutability in extensive alterations 

 by the hand of man. They give us the much-needed warning as to how many 

 features, what extensive additions and what puzzling eccentricities of plan 

 found in these forts, are not to be attributed to the original design. Probably 

 when, by the building of the greater outer wall, the defensive value of the 

 abattis and middle wall was less felt (whether at the same time or on later 

 occasion or occasions) extensive works were carried out on the inner walls. 

 The abattis, as we noted, clung even to the foot of the old outer wall (as it 

 does also at the Black Fort, at Duunamoe,* and at Ballykinvarga caher in 

 Clare) ; its divergence leaving a long open tract between it and the present 

 wall, along with the fragment of wall to the north and west, tells the story 

 clearly enough. The builders demolished the old outer wall from the ridge 

 opposite the east face of the central fort to the avenue at the north-east 

 bend, and also the eastern part of the second wall ; of the materials of these 

 they made an irregular line from the east end of the curve of the latter 

 bowed out like a bastion, and then running in a comparatively straight line, 

 from over 50 feet to about 15 feet from the abattis. It joined the old outer 

 wall rather at right angles, a new gateway being made at the sharp turn. 

 Having been built on the surface of the rock, every trace of the demolished 



'Journal K.S.A.I., vol. xxxvi.,p. liJC. 



•Ibid., vol. xxxviii., p. Sla. 



^ " 0. S. Letters," Co. Galway (ms., R. I. Acad., U d. 3.), 249. 



* If we so consider the former curious wall-loops and outwork at llie gangway and along iho 

 landward edges of the fosse, shown by tho Rpv. Tacsar (Uway in his plan, 18-41, *' Erris and 

 Tyrawley,'' p. 68. 



