midnight
Frank knew that it was the work of the rebel lieutenant , and he hoped that it would soon be his fortune to meet him face to face . One evening , just after supper , the negro appeared on the bank , with some chickens in his hand , which was a signal to Frank that he had something to communicate . He immediately set off alone , in a skiff . When he reached the shore , the negro informed him that the rebel lieutenant was expected at the plantation that evening , and that he would bring with him the mail , which was to be carried across the river at midnight . After paying the negro for his chickens , in order to deceive any one who might be watching them , Frank returned to the vessel , and informed the captain that , if he would give him twenty men , he would fulfill his promise . He did not acquaint him with what he had learned , however , for fear that the captain would send an officer with him , and thus rob him of the laurels now almost within his grasp . As soon as it was dark , Frank picked out the men he wished to accompany him , and started off .