ten o'clock
The Rifle Works had but a single guard . They could be taken in five minutes . Once inside these enclosures , he had unlimited guns and ammunition at his command . The town would be asleep at ten o'clock when he arrived at the Maryland end of the covered bridge across the Potomac . Eighteen armed men were an ample force to capture the unsuspecting town . Not a single policeman was on duty after ten . The people were not in the habit of locking their doors .