soda jerks

Soda jerks were workers at soda fountains who prepared and served ice cream sodas, milkshakes, sundaes, and other fountain drinks.

The term comes from the jerking motion used to operate the soda fountain's dispensing handles.

The job was common from the early 1900s through the mid-20th century, when drugstore soda fountains were social gathering spots: He worked as a soda jerk during high school.