Showing a fleet of steamers, caught fast in the anchor ice out in Lake Superior. Anchor ice is so called for the reason that it is jammed in together in a narrow part of a river in much the same way as a log jam occurs. The ice keeps piling up on top of itself until it is nearly a solid mass to the bed of the river. This string of boats extends back for miles and seldom are they able to release themselves without the aid of tugs or ice crushing boats. Sometimes they are held in the ice for many days.