A steady fire from the fortress delayed the work for some days, but the boom was eventually fixed and the remains of it could be seen at low water so late as 1787.

The castle was next bombarded from the cathedral, but still the brave defenders held out. Then mines were begun in three places, the roofs being propped with dry timber smeared with tar. When completed this was ignited and the cavern falling made a large breach in the wall of the castle.

Seeing defence was no longer possible Captain Courtenay capitulated on the 21st of June, obtaining honourable terms for himself and the garrison. Lord Muskerry took possession the next day.

The captured cannon were used to reduce the neighbouring castles. It is said that the great gun which was mounted on the platform next the town took 35 yoke of oxen to draw it.

Ireton arrived at Limerick in 1651, and began to bombard the castle from the foot of Thomond Bridge. As soon as a breach was effected twenty dragoons, in complete armour, led by Captain Hackett, rushed in, followed by infantry. The Irish fled across the bridge into the further town, breaking two of the arches to prevent pursuit. Barrels of gunpowder were found in the vaults of the castle with lighted matches ready to ignite them.

It seems from the following inscription which was inserted in the south-west tower near the platform that repairs were carried out after these sieges: “Contrived by Lef. Vanderstam, General of their Majesties’ Ordnance, Anno 1691-2.”

In 1787 infantry barracks for about four hundred men were erected within the old walls.

The castle is now used as a Government ordnance store.

Authorities Consulted.
M. Lenihan, “Limerick: Its History and Antiquities.”
J. Ferrar, “History of Limerick.”
J. Dowd, “Limerick and its Sieges.”
FitzGerald and M’Gregor, “History of Limerick.”
Proceedings of Kilkenny Archæological Society.
Joyce, “Irish Place Names.”
Parliamentary Gazetteer.
State Papers.
Carew MSS., with Book of Howth.
State Documents.