The daughter of U.S. Attorney General Alexander Mitchell Palmer rides a three wheeled scooter on the sidewalk near her home in Washington, DC in 1920 when she was 10 or 11 years old.
Just a year before, her father was the target of a failed assassination attempt when an anarchist tripped on a series of iron wickets lining the front entrance of the home. A package bomb carried by the would-be assassin exploded in his hands.
This photo from the same time period in D.C. shows a similar scooter that appears to be driven by a treadle. These are Rita and Ruth, daughters of Danish diplomat Roger Nielson.
52 years later, an act of Congress established the Consumer Product Safety Commission, which will eventually improve the safety of sidewalk scooters and iron wickets.