A “hydraulic ladder,” or mobile escalator, has been developed for use in firefighting.
According to Popular Science, the device is “a cross between a conveyer belt and a ladder,” and it “could help firefighters quickly shuttle victims out of burning buildings.”
In a rescue, firemen could extend Denison’s hydraulic ladder to windows as high as 113 feet. But rather than clamber up the ladder, the firefighter would hop on, and the rungs would roll up at 200 feet per minute—more than twice the average climbing speed of a firefighter weighed down by 130 pounds of gear. The firefighter would ride to a window, load unconscious victims into a rescue bag, hook the bag to the ladder, and shift it into reverse to bring the person to safety.
Extra “rungs” would be stored inside the firetruck down below, to be used as needed for reaching higher floors.
Beyond their role in firefighting, however, these escalators on the move—mechanical detachable staircases moving block to block—suggest interesting architectural possibilities for temporary diagonal passage through the city.