A ship on the stocks was more easily preserved from decay than one in the water. With precisely the same idea the authorities at the end of the war disbanded the bulk of the _personnel_. Upon a war appearing likely, the press-gang was always available to supplement any deficiency in the rank and file not filled by allowing jail-birds to volunteer. Officering the fleet was a less easy matter. The choice lay between retired officers more or less rusty, and the best of the “prime seamen,” who had been afloat in such warships as were retained in commission. The Admiralty selected its officers from both indiscriminately. There is this much, but no more, warrant for the idea that in the old days the sailor from forward could rise to the highest ranks, while to-day he cannot do so. The fact is correct enough, but the circumstance had nothing to do with inducements and encouragements. Once on the quarter deck the tarpaulin seaman, if he had it in him, might win his way to high rank and fame, as did Benbow, Sir John Balchen, Captain Cook, and several others. But he obtained his footing on entirely utilitarian grounds which passed away when a more regular system of _personnel_ came into custom. In the year 1753, a Dr. Hales was instrumental in one of the greatest improvements ever effected in the navy. To him was due the adoption of a system of ventilation with wind-mills and air pumps. The immediate result was a very great reduction in the sickness and death-rate on shipboard, the Earl of Halifax placing it on record that for twelve men who died in non-ventilated ships, only one succumbed in the ventilated vessels. Early in 1755, a war with France became probable on account of hostile preparations made in North America. As a matter of precaution a French squadron on its way out was attacked and two ships captured. Something like three hundred French merchant ships were also taken during the year. War, however, was not declared on either side! Early in 1756, news was received of French designs on Minorca, a considerable expedition collecting at Toulon. After some delay, Byng left England with ten ships of the line, picked up three more at Gibraltar, and sailed to relieve Minorca, where Fort St. Philip was closely invested by 15,000 troops. Supporting these last was a French squadron of twelve ships of the line, under La Gallisonniére. On Byng arriving, La Gallisonniére embarked 450 men from the attacking force to reinforce his crews, and on May 20th ensued the battle of Minorca, which resulted in the defeat and retreat of Byng.[32] Ten days later the British force in the island surrendered.