Antique 1933 Keuffel & Esser N4053-3 Polyphase Mannheim Simplex Slide Rule
Up for Sale is a Rare and Unique. Antique 1933 Keuffel & Esser N4053-3 Polyphase Mannheim Simplex Slide Rule with Black Leather Case F164. The patent number on this item indicates it was issued in 1933.
This ten-inch one-sided mahogany slide rule is coated with white celluloid. The base has A, D, and K scales.
The slide has B, CI, and C scales on one side and S, L, and T scales on the other side. The indicator is glass with plastic edges held together with metal screws. The front edge of the rule has a scale of 25 centimeters.A paper table of equivalents and slide rule settings, based on U. Bureau of Standards Circular No.
47, is pasted to the back of the rule. The top of the base is marked in red: PAT. 1,934,232 MADE IN THE USA. The left end of the slide is marked in red.The left end of the other side of the slide and the scale of centimeters have the serial number: 756968. The bottom plastic edge of the indicator is marked: PATENT 2,086,502, with KEUFFEL & ESER CO. On the back of the edge.