The strain of this bombardment, said to have been greater than any recorded in the previous history of artillery, proved more than the Spanish ordnance could stand. By the 20th of May the brass guns began to droop at the muzzle, the iron guns to burst, and ammunition to run short. Gradually the enemy’s fire died down, and when there were but nineteen pieces left in action against them the British restored their shattered works, and mounting thirteen new guns and more than a hundred mortars poured upon the Spaniards a storm of projectiles almost equalling that which had scourged the defenders of the Rock. By dint of tremendous exertions a hundred guns were placed in position at the beginning of June, and then the tables were turned, for this mass of ordnance opened upon the Spaniards with such a crash that not a single gun was able to reply; the trenches became a heap of ruins; the parapets of the batteries took fire, and the magazines blew up. The first day’s cannonade drove the enemy from their forts, and gradually the whole line of works was completely knocked to pieces. On the 23rd of June the news reached Gibraltar that a suspension of hostilities had been arranged between the Governments of England and Spain: all fighting then ceased; the soldiers had played their part, and it was now for the diplomatists to settle the differences between their respective countries. The British losses were remarkably small. Five officers were killed or wounded; in the other ranks 69 were killed; 49 died from wounds or disease, and 207 were wounded. It is not known how many of the XVIIIth were injured, as the casualties of the Minorca contingent are given as a whole. To the Spanish army, on the other hand, the siege proved very costly. Fifteen officers were killed, 42 wounded: of the other ranks 346 were killed, 1119 were wounded, and more than 5000 died of sickness or were permanently invalided by the hardships they had undergone. No less than 875 Spaniards deserted during the siege, some of whom surrendered to our piquets and brought much useful information to the Intelligence officers of the garrison.
When the siege was over, the detachment of the XVIIIth rejoined headquarters at Minorca, where the regiment remained until 1742. Nothing would have been known of the life of the Royal Irish during this period had not copies been preserved of a curious correspondence between Major Gillman, who was in command, and Major-General Armstrong, the Colonel of the regiment.[72] The officers were greatly disturbed at the quality of the recruits received from home, and Gillman in 1729 thus reports on a recently joined draft of sixteen men. “They are the worst I ever saw; two of them the officers would not draw for: one of them wanting above half of his right foot, the other having his backbone and ribs of both sides distorted in a prodigious manner, by which means he is an object of compassion, both of which are to be sent back to England at the expense of the person that recruited them.”