 A survey carried out at the end of the 1730s suggested that the castle had ten artillery positions, but that there were not enough guns on the island to arm both the castle and the other defences, and that some of the guns that were available were unusable.In 1739, the War of Jenkins' Ear broke out between Britain and Spain, and the decision was taken to improve the defences at Cromwell Castle.Abraham Tovey, the Master Gunner at the nearby fortification known as the Garrison, constructed a large gun-platform for a battery of six guns on the south-west side of the tower, possibly on top of any pre-existing 16th-century platform.