DescriptionArchitect's Convertible Y [Wye] Level No. 5115 made by Keuffel & Esser Co., New York (Hoboken), 1911. Instrument and accessories in mahogany fitted case with lock. Serial number 24952. Level with dust cap; sunshade; 2 trunnions (used as removable axis for vertical sighting; metal trivet with two (lacking one) removable legs; plumb box; an accessory tool whose function is not yet determined. Non-brass metal parts have gun metal finish. Box: 13" wide x 5-1/4" deep x 8-1/4" high; remants of leather strap attachements on sides; hinged lid with clasps and lock with escutcheon plate (original?); manufacturer's plate with serial number 24952 on lid above lock (Montreal is last listed branch); printed paper label inside lid with ink stamped model number and serial number (label has vignette depiction of Hoboken buildings.) Date of item established from list of serial numbers published in January 1991 issue of "Backsights," Surveyor's Historical Society Magazine. List records the first used serial number of the year which places this instrument in 1911. Keuffel & Esser Co. main office and factories were in Hoboken in the period when this item was made.