contained the power position in the Inland Sea, Malta which controlled the nar- rows between Sicily and the North African coast and effectively blocked the passage from the eastern to the western Mediterranean, and Corfu, the key that locked up the Adriatic. Minorca, Corsica and Sicily were all evacuated.
Gibraltar had been British since 1704, a naturally strong three mile rocky peninsula reared up to face the flat Spanish isthmus at almost sea level. Spanish fortifications had been inherited and modernised, but the main strength lay in the sheer character of the Rock honeycombed with galleries. The idea of tunnelling in the solid rock was not new to British engineers - they were already doing it at Minorca when, in May 1782 during the Great Siege, Sergeant Ince suggested cutting tunnels and excavating casemates in the north face of the Rock to cover the isthmus, part of which was already flooded to form an inundation in front of the main land front. Tunnelling continued at a pace to provide, according to the enemy, "works worthy of the Romans" 7 and eventually the Rock of Gibraltar was converted into a maze of warrens.
In 1787 Lieutenant-Colonel Pringle made proposals for converting part of the waterfront defences, using frontal fire from 78 muskets against any at- tempted landing and providing a projecting two-storey caponier armed with muskets. From vaulted casemates cannons were to fire out to sea.8 We see the beginning of the change from a dependance upon enfilade fire across the flanks of defences, to frontal fire made possible by the increased range of guns and the increased rapidity of their fire. Montalembert, the great innovative French engi- neer, had praised the British defences during the great siege, and, largely as a result of them, had advocated the re-introduction of gun casemates.
To hold an enemy at bay outworks at sea were proposed and, in 1808, Nel- son recommended the use of floating batteries anchored in the Bay of Gibraltar. Sea forts were not new. They go back to antiquity and the British had begun one in the Bay at Tangier.10 The Russians made full use of them before Kronstadt and the British built them in the Solent to protect the approaches to Ports- mouth11. In 1868 Colonel Jervois recommended the construction of a sea fort in the shoal water off Gibraltar. 9 12
Corfu had been long covetted, "a place of great strength much improved by art"13 where elaborate Venetian fortifications augmented by the French stood in magnificent array. Under the terms of the Treaty of Paris in 1815 the British occupied the island and held it for fifty years, a half century of procrastination about what to do with the aging existing fortifications. An early proposal called for the establishment of a triangle of defence based on the citadel, Fort Neuf, where a great central keep in the form of defensible barracks was completed in 1847, and Vido island which covered the fine roadstead. Fort George, begun in 1824 on the island, is probably one of the first examples of the pentagonal forts later built all over the world, and by the British at Portsmouth. It was fan-shaped