• 455 Martinson, Los Angeles
  • 8 (043) 567 - 89 - 30
  • support@email.com
  • ARISTO 90107 specially commissioned model for calculating the lifespan of filament lightbulbs
  • Koch, Huxhold & Hannemann (KHH) - made the surprising System Korte slide rule that does addition & subtraction
  • Smallwood Folding Shoe Sizing Stick in metric for French shoe sizes 10-48 in increments of a Paris point (⅔ cm)
  • Lawrence MIT Antenna slide rule for radar antenna performance was classified during WWII by UK & US governments
  • ALRO-made ruler unusually with a cursor for analysing ECG printouts of the cardiac Sinus Rhythms
  • Hatters Gauge - for measuring the size of a hat but unusually calibrated in metric & imperial
  • Glovers Rule - for measuring the length of a glove in imperial inches
  • Unusual non-logarithmic QR 41 military model by Dennert & Pape (D&P) for training anti-aircraft gunners
  • Colour combinations slide rule made by German WH-Wohnen for Interior Designers
  • Professor Fuller’s Drum Calculator from 1878 - made by W.F. Stanley
  • Modern wristwatch with slide rule bezel calculator made by German maker Kienzle
  • Ruxton made Multi-Vider combined drop-lead pencil & slide rule
  • Rare Otis King Model N for Retail & Monetary with white scales (422 & 424) on a black background
  • Darnley’s Rotable Lightning Calculator/Pencil Case calculating aid
  • Makeba made Kombinator combination pencil & slide rule
  • Rare Carbic-made Fischer Calculator slide rule
  • Specialist slide rule for a national home cable radio broadcasting system offered in The Netherlands from 1930 to1970
  • Smallest drum (≈ 2.4m) made by renowned Swiss maker LOGA

Son of a bus driver ....


My mother always insisted he was a “coach driver” but no matter, from my father I inherited a love of motoring. I was born in England but apart from growing up and marrying Ros in the UK, since 1975 the family home has been in one of the famous bulb-growing areas of The Netherlands. Ros and I hold dual Dutch and British nationality - so no pre or post BREXIT problems!

I worked 25 years for an Oil Major – ending up as a Global I.T. Strategist. Retiring early, Ros and I enjoy travelling and watching our married daughter Siân’s family grow up – we proudly have a granddaughter and a grandson.

By harnessing the WWW to share my collection and my published articles will, I hope, provide a useful source of information to other avid collectors or just surfing visitors to the website.

I am a member of the British Slide Rule Circle (UKSRC), the Dutch Circle for Historical Calculating Instruments (KRING) and the German Rechenschieber-Sammler-Treffen (RST) online group. I am also a Fellow, 2011 Award winner and since 2021 a Director of the American Oughtred Society.

If you have any questions or you are just looking for a good home for your trusty slide rule please use the details shown in the footer below or in the CONTACT tab above to get in touch.

Eur Ing. David Rance

Retired from work but not from life!