I found this story on Futility Closet here.
"James Boyle patented this hands-free hat-tipping device in 1896.
"'The hat is detachably secured to the working parts of the device that raise the hat, completely rotate it, and deposit it correctly on the head of the wearer every time said person bows his head and then assumes an erect posture.'
"There’s no record of how the ladies received it."
Surely this defeats the purpose of tipping your hat to someone at all. It's very, "Hello, madam. You are worthwhile enough for me to bow my head to you, but involving my arms? You're just asking for too much."