Rara calcolatrice Otis King modello L tipo A anni 20 con scale 416 e 417 in custodia

This is a rare example of an early Otis King's cylindrical calculator model 'L' type A, but with 416 and 417 scales, much less common then the later model L's which had 429 and 430 scales. Patentees & Sole Manufacturers, Carbic Limited, 51 Holborn Viaduct, London E.C.1.'.

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