Spalding Adding Machine
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. At last count there are 23 known examples worldwide.
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