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Rapid calculator

Another one of the few American pinwheel machines, this time from Philadelphia. The machines were built by the Rapid Calculator Co., established by a German immigrant become U.S. citizen, Otto P. Schuman. in association with Richard C. Rosenthal. Two patents were taken out, one for the carriage movement mechanism, one for the clearing mechanism of the setting register. No patent appears to be available for the special locking device incorporated in the crank. The address is given as "S.W. Cor. American and Cayuga Sts, Philadelphia". The closest match in Philadelphia is West Cayuga Street, in which there is only one contemporary industrial building. Of course the Rapid Calculator company building could have been torn down. An early address is 20 S. 18th Street. That building is very small , but who knows, perhaps large enough for cranking out (excuse the pun) a few 100 calculators in the early days ?

Early incarnations of the Rapid calculator have the chunky clearing levers and special carriage movement system, but still show a regular handle. This is a later model, where the usual pinwheel cylinder lock with a rod in the crank rest shifting outwards as you pull the crank handle from its resting stop is replaced with another very chunky handle of which the lever itself tilts outwards, doing away with the support casting for the crank. Very innovative system that. Also, the input field looks very racy in these later models, as the top of the input field is slanted towards the user, instead of horizontal in most other machines, as well as the early Rapid calculators.

Rapid Calculator  picture 1

Rapid Calculator  picture 2

Rapid Calculator  picture 3

Handle extended :

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American and proud of it:

Rapid Calculator  picture 6