From "The Wonders of Ireland" by P. W. Joyce, 1911
In the year of our Lord 1055, on Sunday the feast day of St. George, the people of Rosdalla, near Kilbeggan in the present county of Westmeath, saw standing high up in the air, a great steeple of fire, in the exact shape of a circular belfry, or what we now call a round tower. For nine hours it remained there in sight of all: and during the whole time, flocks of large dark-coloured birds without number kept flying in and out through the door and windows. There was among them one great jet-black bird of vast size; and while he remained outside the others flew round him in flocks; but whenever he entered the tower they nestled in thousands under his wings, remaining there till he returned to the open air, when they again came forth and flew round him as before.
Sometimes a number of them would swoop suddenly down, and snatch up in their talons dogs, cats, or any other small animals that happened to lie in their way; and when they had risen again to a great height they would drop them dead to the ground.
At last they flew away towards a neighbouring wood; and the moment they left the tower it faded gradually from the people's view. The birds perched on the trees, the great bird choosing a large oak for himself; and so great were their numbers that the branches bent to the ground under their weight. There they remained for some time as if to rest; when suddenly they all rose into the air; and when the great bird was rising he tore the oak tree by the roots from the earth, and carried it off in his talons. The birds then all flew away, no one could tell whither, for they were never seen or heard of afterwards.