Collections Item Detail

DescriptionParagon Geological Survey Alidade, model 5093A, made by Keuffel & Esser Co., New York and Hoboken, (1959.) Metal and glass, 18" long x 3" wide x ca. 8-1/2" high (with striding level attached); sand color paint finish. Original wood case with hinged lid: manufacturer's printed metal plate inside lid plus a printed paper label re servicing. With: sunshade; separate striding level; screwdriver; two spare bubbles [replacement level vials]. Also printed product sheet: "New extra sensitive induction damped Compass Needle on K&E Paragon Alidades." Copyright 1951; separately catalogued, but imaged here, as archives 2009.006.0234.01. Lacking: lens cap; adjusting pins. Serial number, 163196, and manufacturer's name engraved on blade at front end. Date of manufacture determined from serial number marked on blade. The number places it as manufactured in 1959 based on "First Instruments of the Year" serial number chart in January 1991 issue of Surveyor's Historical Society magazine, "Backsights." Model number does not appear on object. Also known as a high-post alidade. Standardized instrument for use by the U.S. Geological Survey. The alidade was for use in plane table work. It is seen and described in the 42nd edition catalog of 1954 on pages 328-329. Plane tables and tripods were listed separately. Note: "Spare Bubbles" marked with plate on wood block secured to case bottom below striding level storage slot. Each bubble is marked with its replacement part number. K&E main office and factories were in Hoboken when this item was made.