09-015. American, after 1895, and stamped on the front "PERFECTION SELF-ADDING RULER, PAT, JAN. 8th 1895, COLUMBIA NOV. CO., MANUFACTURERS, NEW YORK." Made of hardwood, 15" long x 1 1/2" wide with a brass ruling edge, an inset celluloid strip divided 1-45 and 46-90 with a slit in the center; a dial face graduated 1-5 with brass pointer, and an internal cloth ribbon that can be moved with a stylus for adding a column of numbers. The reverse has a inset celluloid strip with detailed instructions. This unusual early American-made column adder is in fine display condition; however, the brass pointer on the dial does not move.
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