Technology
The type cylinder, like the later typeball of the IBM Selectric typewriter, was easily removed, allowing users to select among fonts. Striking a key turned the cylinder to the appropriate orientation while inking the type as it tipped downward to strike the paper. Holding the Cap or Fig keys shifted the cylinder along its axis to use either the middle row, for capital letters, or the upper row, for special characters.
Read more about this topic: Blickensderfer Typewriter