Designed by Charles Spiro, a New York watchmaker, this was one of the first typewriters that allowed its user to see what they were typing, its type bars striking the paper from above, not below as in earlier designs. Unfortunately, the typist still has to peer over the type bars, which are placed between the keyboard and the paper. The machine's name comes from a mechanism that locks each bar in position when printing to prevent jamming. The double keyboard enables both capitals and lower case letters without the use of a shift key.
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