Some reaction ferries operate using an overhead cable suspended from towers anchored on either bank of the river. Others use a floating cable attached to a single anchorage that may be on one bank or mid-channel. Where an overhead cable is used a "traveller" is usually installed on the cable and the ferry is attached to the traveller by a bridle cable. To operate the ferry either the bridle cable is adjusted or a rudder is used, causing the ferry to be angled into the current, and the force of the current moves the ferry across the river.