Sir Cumference wrote:

Electric ball typewriters could do that, and the US government
had lots of them.


BZZZZTTT!!! Wrong! The Selectric could not do proportional spacing. I
worked for IBM and worked on the Selectric units that were use as the
output device for the System 360 mainframe console. You haven't a clue
about which you speak.



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Composing typewriters


Derogatorily called "Strike-on" composition, the composing typewriter
was used for camera-ready copy in the quick-print business, in academic
publishing, and small weeklies, where cost and turn-around were the
driving factors. The best were capable of proportional spacing,
justification, and handling multiple fonts. The familiar IBM Executive
and Selectric can be considered to be in the low-end of this family; the
IBM Composing Selectric was a computer-driven, auto-justifying, high-end
system.

* Friden Justowriters (2)
* Varitypers (2) with 60 fonts
* Densmore
* Underwood
* L.C.Smith
* NCR
* IBM Composing Selectric (4) (w/o computer or tape units, but w/
multiple type balls)
* other

http://www.museumofprinting.com/inventory/invty.html


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