eight o'clock
The lights in the fort served as a mark by which he could note his progress ; and an hour after starting he was well abreast of them , and knew that the current must be helping him more than he had expected it would do . Another hour , and he began to swim shorewards ; as the current might , for aught he knew , be drifting him somewhat out into the bay . When he was able to make out the dark line ahead of him , he again resumed his former course . It was just eight o'clock when the guard had passed through the gate . He had started half an hour later . He swam what seemed to him a very long time , but he had no means of telling how the time passed . When he thought it must be somewhere about twelve o'clock , he made for the shore .