DescriptionEngineer's chain scale, 12" triangular, Paragon model 1631P, made by Keuffel & Esser Company, (Hoboken, N.J.), no date, circa 1940-1960. Machined hardwood (boxwood) with applied white celluloid plastic rules; divided 10, 20, 30, 40, 50, 60 parts to the inch; black ruling; 7/8" triangle with groove on all long sides; 12" scales; overall 12-1/2" long. Marked with model number and "Keuffel & Esser Co. N.Y." and product line "Paragon." Catalogue name: Triangular Paragon Scales, Engineer's Chain Scales. (Note: this item is sometimes mislabeled as an architect's scale or rule.) Date of this item may be earlier. K&E main offices and factory were in Hoboken during the period when this was manufactured.