It is not generally known that a round tower stood in the City of Dublin as late as the year 1775. This tower, which was considered one of the most ancient of its type, was known as the tower of St. Michael of the Pool, and stood beside the millrace from the Poddle River, which now runs under the gate of the Lower Castle Yard.
This early Christian ecclesiastical site can be placed at the west side of Great Ship street. The tower was in a bad way about the year 1738, but Dean Swift and others interested themselves in its preservation and some repairs were effected. Unfortunately, the steps then taken to stay the ravages of time proved ineffective, and in October, 1775, after a great storm, the tower was found to be in a dangerous condition - so bad, in fact, that it could not be repaired.
The Irish Times, March 20th, 1930.