Hitchhiking is a combination of two words.
The term has two origins that collided in 1923 as an inexpensive way of traveling.
Hiking means to “walk vigorously” and has been around forever.
In 1578 the word hitch surfaced as a nautical description of “fastening with a hook” but eventually gained broader use as in “hitching a team of horses to a wagon” or “hitching a trailer to a car.”
Hitchhike was first employed in 1880 to describe hitching a sled to a moving car.
The use of the thumb by someone looking for a ride is a symbolic “hook” to signal the hitchhiker’s wish to become attached to a passing car.
You state that hitchhike was first employed in 1880 to describe hitching a sled to a moving car.
Can you provide a site in a newspaper, magazine etc where it was used inthis way?
Thanks for any additional information you may be able to provide.