Every owner, officer, or person in charge of any vessel, craft or float navigating the harbor shall sound or cause to be sounded a steam whistle to signal bridge tenders to open and swing bridges, and such signal shall be three sharp, short sounds of the whistle, to be given in succession as quickly as possible and not to be prolonged, and the whistle used for this purpose shall be of suitable size to be heard; provided, such signal shall be four sharp, short sounds of the whistle for vessels approaching the Northwestern Railway Bridge near W. Kinzie Street, and the Chicago, Milwaukee, St. Paul and Pacific Railway Bridge near W. North Avenue from either direction, and shall be five sharp, short sounds of the whistle for vessels approaching the Lake Street Bridge from the north.
(Prior code § 38-48)