Appendix 3: A K&E Cursor Study

Within a single decade during the 1910s, Keuffel & Esser redesigned and implemented new cursors within their rules to the point of confusion among today’s collectors.  In this section, we’ll study the various types of cursors across the K&E body of rules, make some conjecture regarding what K&E might have been thinking, and discuss some of the important factors as it concerns the slide rule collector.

This is presently a running timeline rather than a full write-up — as with the rest of this book, expect it to grow into a proper discussion of each design and why K&E moved on from it.  In the meantime, see the “K&E Rotting Cursor Syndrome” sidebar in Chapter 1 for why the celluloid-rail generations of this timeline are the ones to inspect most carefully before buying.

• All-metal (brass) chisel indicator (1883 to 1906)
• Glass indicator — single line
• Glass indicator — double line (special)
• Decimal-keeping cursor (special)
• Clamshell metal-framed glass (1901 to 1913)
• Column metal-framed glass (1913)
• Frameless glass with metal rails (1914)
• Frameless glass with celluloid rails (1915)
• Bent celluloid with metal spring (1915)
• Frameless glass cursor with wooden rails (1926 to 1940)
• All-celluloid cursor (1930, for the Model 4058 and the Ever-There series)
• Metal-framed plain glass cursor (1936)
• Flanged plastic cursor rails (1933)
• Improved glass cursor (1936)
• Improved glass cursor with ivorite rails (~1950)
• Unbreakable Indicator (1953)
• Magnifying Cursor
• Custom glass indicators (see the 1936 catalog)
• K12/GP-12 runner

Continue to Appendix 4: Bibliography · Back to Table of Contents