OGANOG0106011
Fuller's Cylindrical Slide Rule London England Early 20th Century
Fuller's Spiral Slide Rule
Fuller's cylindrical slide rule. It consists of an outer wooden cylinder that slides up and down and rotates, covered with paper marked with a graduated spiral logarithmic scale; inside is a longer wooden cylinder, also covered with paper marked with decimal tables. A brass index is screwed to the top of the neck, a second, longer brass index is screwed to the mahogany base and marked with a scale. The outer sliding cylinder is marked near the top: “FULLERS SPIRAL SLIDE RULE”; at the bottom it's marked: “ENTD. STATS. HALL / STANLEY, Maker, LONDON". The upper part of the long brass index is engraved: 1791 (/) 1903, for which it can be assumed (as for another similar specimen, preserved at the National Museum of American History) that the first is the serial number, while the second the year of completion. George Fuller, professor of civil engineering at Queen's University in Belfast, Ireland, patented this instrument in 1878; the Stanley firm produced about 14,000 Fuller spiral slide rules in nearly a hundred years.