The date is between twenty and thirty years ago. The place is an English sea port. The time is night. And the business of the moment is dancing. The Mayor and Corporation of the town are giving a grand ball, in celebration of the departure of an Arctic expedition from their port. The ships of the expedition are two in number the Wanderer and the Sea mew. They are to sail (in search of the Northwest Passage) on the next day, with the morning tide.