The Spalding Adding Machine was first patented by inventor Cyrus G. Spalding in 1874. Initial production was by the C.G. Spalding company of Springfield, Massachusetts, then by J.R. Anderson & Company of Nassau, New York and, finally, by The Surprise Company in New Haven, Connecticut. The last company rebranded The Spalding as The Surprise Adder. Being a resident of Connecticut, I would be especially thrilled to find an example labeled as The Surprise. Though, let's be honest, any version will do.

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As of 2022, there are at least 28 known examples with serial numbers ranging from 9 to 1064.

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Have one for sale? Please email me at Antikey.Chop@gmail.com or call +1 (860) 729-2252

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