Now, architect Thomas Randall-Page has developed an updated version of this type of bridge for east London’s Cody Dock—a 19th-century wharf on the River Lea. Randall-Page’s proposed steel bridge will somersault over the river when boats pass through, making it equal parts acrobatic and functional. Its square frame will rock in a full revolution along the river it lies across, aided by teeth-lined railings that slot into cavities on the opposite side for a perfect fit.