Patrick Weston Joyce

Dalkey Island near Dublin. The Irish name is Delg-inis (O'Clery's Calendar of Irish Saints, or, The Martyrology of Donegal), thorn island; which the Danes, who had a fortress on it in the tenth century, translated to the present name, by changing Delg into their word Dalk, a thorn; and substituting the northern word ey, an island, for inis.