Kk^E—The Black Fig's Dyhe. 313 



appear in the map on the road from Lisnadill about 4,000 ft. to south of the 

 " Cast." The Tain Bo Ciialnge preserves a reference perhaps to this entrench- 

 ment, the object of whose erection must have become quite forgotten at the 

 period at which that epic was composed, the earliest version of which is 

 thought to date about the eighth century. It is as follows : — " Then the bull 

 went and fifty heifers with him to Slieve Culind (Gullion), and his keeper, 

 Forgemen by name, followed him. He threw off the three-fifties of boys who 

 used always to play on him ; and he killed two-thirds of his boys, and dug a 

 trench in Tir Marcceni in Cualnge before he went."^ 



And again : — He " went on Slighe Midluachra in Cuib . . . and made a 

 trench there : hence Gort Buraig, the field of the trench." If this earthwork 

 was a westerly continuation of the Glen Eee entrenchments from Scarva, it 

 is evident that they could never have been designed as a protection against 

 an inroad from Ulidia to Emain Macha. I consider it as possibly a detached 

 inner line of defence near the capital, where a last stand could be made in 

 case a Southern enemy succeeded in forcing their way north by the Forkhill 

 pass. Emania, however, after above 150 years' struggle against the ambition 

 of the Kings of Tara, fell a prey to the invading host of the Collas in the 

 year 332. 



If, therefore, we must dismiss this hypothesis as to the Dane's Cast in 

 Glen Eee having been erected to confine the Ultonians, we must next 

 consider whether there is any other historical topographical boundary with 

 which these Irish earthworks coincide. It would be presumption on my 

 part to differ from the conclusions of that great master of Irish topography, 

 O'Donovan, if it were not that his researches, during the progress of the 

 Survey of Ireland, were cut short by the parsimony of the Government of 

 his day, so that certain additional lengths of the structure in the West, 

 hitherto unknown, were wanting to unravel the mystery of this prehistoric 

 work, which he would without doubt have done. His first suggestion was 

 that while the Dane's Cast was the defensive frontier of Oriel against Ulidia, 

 the other known part of the Black Pig's Valley, namely, the Worm Ditch, 

 constituted its southern frontier. Now, Oriel was formed in the fourth 

 century, after the destruction of Emania and conquest of Ulster by the 

 three Collas ; and its territory comprised the three counties of Monaghan, 

 Armagh, and Louth, together with portions of Tyrone and Fermanagh. 

 We have already traced the course of the Worm Dyke from near Wattle 

 Bridge, at the western extremity of the southern verge of Monaghan, to 



1 " The Cattle E.aid of Cualnge," translated by Winifred Faraday. Grimm Library. London : 

 David Nutt. 



