The passion for identifying existing earthworks with sites mentioned in ancient Irish history or legend has been a most serious hindrance to the progress of real archæological knowledge in Ireland. It is not until one begins to look into this matter that one finds out what giddy guesswork most of these identifications of Irish place-names really are. O'Donovan was undoubtedly a great Irish scholar, and his editions of the _Book of Rights_ and the _Annals of the Four Masters_ are of the highest importance. The topographical notes to these works are generally accepted as final. But let us see what his method was in this part of his labours. In the _Book of Rights_, he says very naïvely, about a place called Ladhrann or Ardladhrann, "I cannot find any place in Wexford according with the notices of this place except Ardamine, on the sea-coast, where there is a remarkable _moat_."[1053] No modern philologist, we think, would admit that Ardamine could be descended from Ardladhrann. In the same way O'Donovan guessed Treada-na-righ, "the triple-fossed fort of the kings," to be the motte of Kilfinnane, near Kilmallock. But this was a pure guess, as he had previously guessed it to be "one of the forts called Dun-g-Claire." To the antiquaries of that day one earthwork seemed as good as another, and differences of type were not considered important.[1054] * * * * * The following list of early Norman castles in Ireland was first published in the _Antiquary_ for 1906. It is an attempt to form a complete list from contemporary historians only, that is, from Giraldus Cambrensis and the "Song of Dermot," and from the documents published in Sweetman's _Calendar_, of the Norman castles built in Ireland, up to the end of John's reign.[1055] Since then, the task has been taken up on a far more philosophical plan by Mr Goddard H. Orpen, whose exceptional knowledge of the history of the invasion and the families of the conquerors has enabled him to trace their settlements in Ireland as they have never been traced before.[1056] Nevertheless, it still seems worth while to republish this list, as though within a limited compass, consistent with the writer's limited knowledge, it furnishes an adequate test of the correctness of the Norman theory, on a perfectly sound basis. The list has now the advantage of being corrected from Mr Orpen's papers, and of being enlarged by identifications which he has been able to make.[1057] *ANTRIM[1058] (_Cal._, i., 88).--A royal castle in 1251. Present castle modern; close to it is a large motte, marked in 25-inch O.M. AQ'I (_Cal._, i., 13).--Unidentified; perhaps an _alias_ for one of the Limerick castles, as it was certainly in the county of Limerick. ARDFINNAN, Tipperary (_Gir._, v., 386).--Built in 1185, immediately after John's coming to Ireland. No motte; castle is late Edwardian and partly converted into a modern house; one round tower has ogee windows. [B. T. S.]