two o'clock
exclaimed Walter excitedly . `` Yes , but their fire was equally harmless ; but later in the day Lawrence 's guns quickly dispersed some of Percy 's men who were attempting to cast up intrenchments , and in the same way several light boats , whose men were engaged in sounding the channel nearest the fort . `` The next day was occupied in very much the same way , but on the third the garrison perceived that an assault was to be made from both land and water . At two o'clock the vessels were seen approaching , and Lawrence called a council of officers . `` All were determined to resist to the last , and if finally compelled to surrender , to do so only on condition that officers and privates should retain their arms and private property , be treated as prisoners of war , and protected from the savages . `` The words adopted as the signal for the day were , ` do n't give up the fort . ' `` At half past four the battle began , the four vessels opening fire simultaneously , and pouring broadside after broadside upon the fort , which returned a fearful fire from its circular battery .