People and Their Slide Rules
Peter Hopp, United Kingdom

Paintings of People with Slide Rules
  • Ir. S.G.J.H. van Schaik
  • Sir James Hopwood Jeans
  • Unknown man, possibly an engineer or architect
  • Henry Ford?
As a change between “famous” and “not so famous” people in my selection of candidates, this time we have paintings of people, some famous and some not so famous, or maybe just unknown at this time. I never fail to be amazed at what people know, so maybe we will find definite attributions to the pictures of the two unknown subjects. If my collection of images must be categorised, then the category called “Paintings of People with Slide Rules” is probably the least well populated, with very few examples. However, it does mean that those in that category are really rather special in different ways.

The images I have chosen are of 2 named subjects, followed by a definite unknown and finally a possibly named subject. The first is a splendid portrait by the Dutch artist Carel Willink (1900 –1983) of Ir. S.G.J.H. van Schaik (Fig. 1), painted in about 1943, when he was Managing Director of AKU, (Algemene Kunstzijde Unie), later AKZU, in Holland. He is shown with a ‘Cuntz’ slide rule, made by Schacht & Westerich amongst others, (see UKSRC Gazette No 4, Autumn 2003). I was originally sent a photo of the painting by IJzebrand Schuitema with a request to include it in Skid Stick (the three monthly magazine of the UKSRC) with a plea to anyone who had such a slide rule, and might be prepared to let Mr van Schaik have it.

Next is another lovely painting, this time from “Punch”, the English monthly satirical magazine, of 27th Feb 1935, of Sir James Hopwood Jeans, (1877 – 1946) astronomer and polymath (Fig. 2), who wrote amongst many other books “The Mathematical Theory of Electricity and Magnetism”. This is a particularly nice picture as it shows the man with a 24” slide rule complete with magnifying cursor. He was obviously proud of his slide rule and had gone to the extent of “improving” its performance with a better cursor.

The third image is a recent addition to my collection, an unknown man painted by the well-known and prolific painter William Derby, (1786 – 1847). It was titled “Portrait of an unknown gentleman” (Fig. 3), possibly an architect or engineer, seated at a desk, holding a slide rule and compass (so said the auction blurb, actually a Gunter’s rule and dividers). This is a watercolour 23 x 17cm, signed and dated 1824, and featured in an art sale in London in March this year. It is rather frustrating not to know who the man is. To have been painted by Derby makes him someone of substance, and it would be nice to identify him.

Finally, courtesy of Bryan Purcell, is an image from the Detroit Institute of Arts, 2007. The panel “Detroit’s Industry” by Diego Rivera includes a business executive (apparently Henry Ford) with a slide rule in his hand (Fig. 4). The whole panel looks most impressive, and that part which includes our “Captain of Industry” with a slide rule is very strong. Whereas it is not obviously Henry Ford (at least I don’t think so) a painting such as this is extremely evocative.

Previously in this series I have included two other paintings of People and Slide Rules. The pictures of Sir Frank Whittle with the jet engine are somehow very different as they included the man and his invention. We could also have included Routledge with his slide rule and rotary steam engine, but I only have that as a monochrome image. Here we have these men painted in glorious colour with a slide rule as an integral part of the painting, which somehow adds emphasis to that all-important slide rule. The shame is that the other obvious painting, which I could have included, is of our hero The Rev. William Oughtred, who is never shown with a slide rule. How sad!

You, the readership, have continued your generosity by sending me ever more pictures. I really do appreciate every one that is sent, whether it is a repeat of an image I already have, or a new image, I am very grateful that you take the time to let me have these - many thanks.

If you have any images of famous or not-so-famous people pictured with their slide rules, please email the images to Peter, peter.hopp "at"

Peter Hopp

Ir. S.G.J.H. van Schaik
Fig. 1

Sir James Hopwood Jeans
Fig. 2

Unknown man, possibly an engineer or architect
Fig. 3

Henry Ford?
Fig. 4

A Slide Rule Friendship
Ted Hume, San Angelo, Texas

My wife and I had the pleasure to spend some time with Bob Koppany and his wife Margi during the days after the Society’s new Winter Meeting in Las Vegas this past February. But this story began seven years earlier, when I first met Bob at an Oughtred Society summer meeting in Palo Alto, California, for which he was host. I learned that he had agreed to serve as host for this meeting for ten years. This was somewhat surprising, for he lives in Hawthorne, California in the Los Angeles area, some 360 miles distant. I was even more surprised to learn that he had ridden his BMW motorcycle to the meeting! At that point, I knew I had met an unusual person.

Hosting one of these meetings is no small job. Arrangements had to be made with the hotel for the meeting room, refreshment service, tables, table cloths, chairs, morning coffee and pastries, lunch, afternoon refreshments, etc. In advance of the meeting, Bob mailed notices to all OS members in the nearby area (there are a lot of Society members in California). Then he prepared and mailed the meeting packet to attendees. At the meeting he had name tags and table place cards for each attendee and also served as auctioneer.

I learned that he had written and published eight books, and that he was a very talented graphic designer. He is a doctor of optometry by profession, but he has many other interests in addition to slide rules, including the study of Frank Lloyd Wright and his work. Bob is one of the leading scholars on Wright. He worked for eleven years on a beautiful three volume set of large coffee table sized books titled Educating Frank Lloyd Wright, which he published. His two current books are in the final editing process … a physics text and a chemistry text.

At one of the Palo Alto meetings I went with him to the Hanna House, designed by Wright and now owned by Stanford University. It is also known as the Hexagon House, for reasons you can imagine. Bob wanted to measure the sizes of numerous details of the house for his research on the grid he suspected that Wright used in his designs. Bob had deciphered Wright’s design grid and was assembling information on it for a yet another book.

About this time I began working on a project called The Oughtred Society Slide Rule Reference Manual. It was Walter Shawlee’s original idea for the Society to publish this Manual. He felt that the prestige of the Society would lend credibility to it. In fact, he insisted on the rather lengthy technical name for it for this reason. Somehow I learned about Bob’s graphic design talents. After a bit of begging by me, he agreed to do the design and typesetting for this publication.

If you have seen the Manual, you will undoubtedly agree that Bob Koppany is indeed a very talented graphic designer. He is also quite a diplomat. I had spent a lot of time formatting the basic page design using Word. Bob politely suggested that he might offer a different design for my consideration. Much later I learned that he was appalled when he saw my design efforts. I must now agree that my efforts were very amateurish compared to his final result.

Thus began a firm friendship, as we both devoted many hundreds of hours to producing the Manual. Soon thereafter, Joe Soper began writing his book on his years at Keuffel & Esser Co. After Joe finished the text, Bob did the graphic design and typesetting for it. The result … another beautiful book for the Society to publish!

I tried to show my appreciation by arriving at the summer meetings a day early to help Bob set up the meeting room. I once made the mistake of treating him to dinner and a glass of wine … and now this has become a tradition. Just kidding! It is my great pleasure to be a good friend of this amazingly talented man.

Ted Hume

Koppany conducting the auction at the Winter Meeting in Las
       Vegas, 2008
Koppany conducting the auction at the Winter Meeting in Las Vegas, 2008

Re-inking a K&E Slide Rule – A Tale of a Man and His Slide Rule
Ron Knapp, Elk Grove, California

This is a summary of the story of a man trying to get his old, faded slide rule re-inked by K+E. The correspondence between K+E (Lawson Langenheim) and Mr. J.J. Sousa, Chief Engineer of Electric Specialty Co. of Stamford, Connecticut, can be seen in its entirety by clicking on the links to the right. Mr. Sousa’s journey began in 1960 and ended in 1961.


Oct. 24: J.J. Sousa wrote a letter to K+E asking if his “old log-log vector slide rule (#490027) model #4093-3” could be re-inked, and if so, the price to renovate the rule.

Nov. 7: K+E responded to Sousa’s letter and told him it would be possible to have the slide rule re-inked. It would cost $4.50, plus shipping, and it would be done in three to four weeks.

Nov. 8: J.J. Sousa responds with acceptance, and states that, “Any reduction in the delivery date will be appreciated.”

Nov. 14: A packing list is made stating the slide rule has been repaired.

Nov. 22: After receiving his slide rule, J.J. Sousa writes back to K+E in regard to his slide rule being re-inked all in black (instead of the desired original red and black), asking if he could send it in again to have the scales inked in red, as well as black.

Nov. 25: K+E responds stating J.J. Sousa can return it for reworking.

Nov. 28: J.J. Sousa returns the slide rule to be re-inked in red and black.

Dec. 29: J.J. Sousa sends a letter to K+E stating that he received a different 4093-3 slide rule which he would use until he received his rule.

Jan 12, 1961: A receipt, originally dated 11/28/60 with J. Sousa’s name is marked “Paid”.

I have in my possession Mr. Sousa’s original slide rule. (The slide rule has the same serial number as the one listed in the paperwork and his initials scratched into the slide and the body.) Both the slide rule and the paperwork were inside of a K+E 4083-3 box. Other than a few items (the model number, several numbers, the serial number on the slide, and Keuffel & Esser), the slide rule is still inked completely in black. This leads me to ask the question, “Was K+E not able to re-ink the slide rule and just returned it to J.J. Sousa, letting him keep the substitute 4093-3?” Of course I have many other questions, but finding the answer won’t be easy, if even possible.

On a side note, the K&E 4093-3 slide rule was only made until the late 1930s. I find it interesting that around 20 years later, K&E would send a different 4093-3 while they were working on a person’s slide rule. I would very much like to hear of similar stories of people returning slide rules to K+E or other manufacturers and their experiences. If you have such a story, please contact us at

Ron Knapp

Oct. 24 Nov. 7 Nov. 8

Nov. 14 Nov. 22 Nov. 25

Nov. 28 Dec. 29 Jan 12, 1961

Re-inked K+E 4093-3 Slide Rule

Re-inked K+E 4093-3 Slide Rule

Re-inked K+E 4093-3 Slide Rule

Re-inked K+E 4093-3 Slide Rule

Slide Rule Friendships
Ted Hume, San Angelo, Texas

During the past 9 years, I have “met” many interesting and talented people who are slide rule enthusiasts. Most are members of the Oughtred Society. When I say “met” I don’t necessarily mean met in person (although I have had the pleasure to meet many in person … see below). Rather we met and often worked together on Oughtred Society projects via Email or the internet, or I sold slide rules to them when I was operating a website called Ted Hume Slide Rule Trader.

Among these people are:
  • Colin Barnes of the United Kingdom. Leader of the United Kingdom Slide Rule Circle, editor of its journal, the Gazette, and its newsletter, Skid Stick.
  • Joe Bento of Pleasant Grove, Utah. Project chairman of the Oughtred Society Slide Rule Learning Kit; very knowledgeable slide rule enthusiast.
  • Clay Castleberry of Oroville, California. Slide rule collector emeritus and educator of the public about slide rules; contributor to the OS Journal and the OS Bulletin. It was my pleasure to visit with Clay at several OS memetings.
  • Jim Cerny of New Castle, Vermont. Creator of the Oughtred Society’s website, advanced slide rule researcher and collector; has premier collections of 10 cm slide rules, Logarex slide rules, and Faber-Castell slide rules with addiators on the back.
  • Andrew Davie of Tasmania. Founder of the Slide Rule Forum discussion group on his Slide Rule Trading Post website, predecessor of the International Slide Rule Group, who began internet communication among the world slide rule community. Andrew is a hero to me and to many slide rule enthusiasts.
  • Richard Davis of Las Vegas, Nevada. Chairman and host of the new OS Winter Meeting which was held February 2008; advanced collector; has comprehensive collection of Reiss mill finish aluminum slide rules. I have enjoyed visiting with Richard at several OS meetings.
  • Bob De Cesaris of Granite Bay, California. President of the Oughtred Society and very advanced collector of slide rules and mechanical calculators. Expert on pocket watch slide rules and Fuller slide rules. I have enjoyed visiting with Bob at several OS meetings.
  • Deborah Douglas, Cambridge, Massachusetts. Curator of Science and Technology, MIT Museum. Is cataloging the K&E company slide rule collection. It was my pleasure to meet Deborah at the OS west coast meeting.
  • Barry Dreikorn, Indianapolis, Indiana. Author of the comprehensive Index of the Journal of the Oughtred Society, a project on which he worked for several months.
  • Gary Flom of Stockbridge, Georgia. Oughtred Society board member, Coordinator of the Swap Sheet Online, source of many new ideas for Society projects and activities (including the new winter meeting in Las Vegas). After many years of working together on OS projects via the computer, I had the very great pleasure finally to meet Gary at the winter meeting in Las Vegas in February 2008.
  • Paul Huff, Livonia, Michigan. Teaches slide rule to his classes at West Bloomfield High School; is thus one of my heroes. See his article in the OS Journal, Vol. 14, No.1.
  • Richard Smith Hughes, Ridgecrest, California. Prolific author of technical slide rule articles and researcher of antique Egyptian coffins. I have enjoyed visiting with Richard at several OS meetings.
  • Bill Jollie of Madison, Wisconsin. Fellow Hemmi Roid and author of the History section of the OS Slide Rule Reference Manual and the OS website. It was a great pleasure to meet Bill in person a few years ago when he came to Texas to attend the Texas Star Party with us, where we shared our mutual hobby of amateur astronomy.
  • Gerd Keuffel, Bloomfield Hills, Michigan. Great grandson of Wilhelm J.D. Keuffel, co- founder of Keuffel and Esser Company and one of the world’s nicest people. I was a distinct pleasure to meet Gerd at an OS west coast meeting.
  • Ron Knapp, Elk Grove, California. Manager of the Oughtred Society website, lead co-editor of the OS Bulletin, advanced slide rule enthusiast. It was a pleasure to meet Ron in person in 2006 at the OS west coast meeting.
  • Günter Kugel of Germany. Dean of the German slide rule collectors, trader and friend of slide rule collectors around the world. We did a trade in 2008.
  • Mike Konshak, Louisville, Colorado. Webmaster of the Oughtred Society site; founder of the widely used International Slide Rule Museum on the internet. I enjoyed meeting Mike in person at an OS west coast meeting.
  • Bob Koppany of Hawthorne, California. General genius, writer of books, designer of Oughtred Society publications, advanced slide rule collector. We met several years ago at an OS west coast meeting. See special article about our friendship and OS work together.
  • Wayne Lehnert, Antioch, California. Retired Secretary of the Oughtred Society after ten years of service; taught me much of what I know about the Society. It was a pleasure to meet Wayne at an OS meeting and to visit with him at several meetings thereafter.
  • Rod Lovett of the United Kingdom. Creator of the fantastic internet search systems for slide rule sales, literature and Herman’s Catalog; winner of the Oughtred Society Award in 2007 for outstanding service to the world slide rule community.
  • Kate Matthews of Sonora, California. First Vice President of the Oughtred Society, expert on K&E slide rules; serious researcher. I enjoyed meeting Kate at an OS west coast meeting and visiting with her at several meetings thereafter.
  • Steven Mays, Beaverton, Oregon. Co-editor of The Oughtred Society Bulletin, very advanced slide rule researcher and collector. I had an enjoyable time meeting Steven at a west coast meeting and several times thereafter.
  • Clark McCoy of Roseville, California. Membership Secretary of the Oughtred Society, very serious researcher of K&E company and slide rules, has extensive website devoted to K&E. It has been my pleasure to visit with Clark at several OS meetings.
  • Jerry McKenna, Randall, Minnesota. Regular contributor to The Oughtred Society Bulletin, lender of many slide rules for scanning for the OS Slide Rule Reference Manual, advanced collector.
  • John Mosand of Trondheim, Norway. Advanced collector and researcher of Aristo slide rules, frequent contributor to the Journal of the Oughtred Society and the Bulletin.
  • Michael O’Leary, Vermont (deceased). Beloved owner and moderator of The International Slide Rule Group discussion forum on YahooGroups (which is the successor to Andrew Davie’s Slide Rule Forum) , very serious researcher and collector of both K&E and Pickett slide rules, of which he compiled extensive archives of all known models. These archives may be viewed on the ISRG website.
  • Jürgen Nestler of Hausach, Germany. Great grandson of founder of Albert Nestler Co. in Lahr, Germany; generous benefactor of the Oughtred Society, to which he donated 50 new Nestler slide rules for inclusion at no cost to buyers in the OS Slide Rule Learning Kit. See
  • Bob Otnes of Palo Alto, California. Co-founder of the Oughtred Society in 1991, editor of the Journal of the Oughtred Society since that time, very advanced researcher and collector of slide rules and mechanical calculators. Of course it was a rare and great pleasure to meet and visit with Bob at several OS meetings.
  • David Rance of The Netherlands. Frequent contributor to the Journal of the Oughtred Society, serious researcher and collector.
  • Bill Robinson of Phoenix, Arizona. World’s expert on hyperbolic slide rules, author of the archive on these instruments, which may be viewed at in the JOS Plus section. After several years of working with Bill on his projects, it was a great pleasure to meet him in person at the OS winter meeting in Las Vegas in February 2008.
  • Dick Rose of Columbus, Ohio. Very large slide rule dealer, all around nice guy, see , I had the great pleasure to meet Dick in person for the first time at the Winter meeting of the Society in February 2008.
  • Paul Ross of Fair Grove, Missouri. World’s leading authority on Post slide rules and perhaps also Hemmi slide rules, has largest Post collection and possibly largest Hemmi collection; we co-authored the Post slide rule archive (see Slide Rule Universe website ); he authored the Hemmi Slide Rule Catalogue Raisonne, which may be viewed on his website The Slide Rule Trading Co. , he also is a world class contract bridge player. I enjoyed our meeting in person at two OS meetings in Kansas City.
  • Dave Rueb, Martinez, California. Has the most comprehensive collection of K&E slide Rules; grower and producer of Zinfandel grapes and wine.
  • Dagmar Rutzen, Des Plaines, Illinois. Teaches slide rule to her junior high school classes and is thus one of my heroes. See her article in the OS Journal, Vol. 214, No.1.
  • Warren Salomon of Miami, Florida. Fellow Hemmi Roid (he named the group) and avid researcher and collector of Hemmi 50 cm slide rules; see his article in the OS Journal Vol. 14, No.1; see also his article on his favorite slide rules in the current Spring 2008 issue of the OS Bulletin; Warren is the unlikely combination of probate litigation attorney and slide rule enthusiast.
  • Conrad Schure of Freehold, New Jersey. Treasurer of the Oughtred Society; one of the worlds most advanced researchers and collectors of rare slide rules and related instruments; prolific contributor to the OS Journal. It was my pleasure to visit with Conrad at several OS meetings.
  • Walter Shawlee of British Columbia, Canada. Proprietor of the Slide Rule Universe website, the largest and most informative slide rule site, very large slide rule dealer, avid researcher, also is amateur astronomer, with a 40 foot radio telescope dish (which he built) in his back yard! I had the very great pleasure to meet Walter in person in Dallas a few years ago when he was working on a project there. He is truly one of the world’s nicest persons.
  • Rodger Shepherd, Oakland, California. Original co-founder of the Oughtred Society, advanced researcher and collector, retired physician. I enjoyed visiting with Rodger at several OS meetings.
  • Joe Soper, Lakeville, Connecticut. Author of the book K&E Salisbury Products Division Slide Rules, for which I served as editor, published by the Oughtred Society (see; worked for K&E 29 years, managing the Salisbury Division and its slide rule manufacturing for several years.
  • John Spivey of College Station, Texas. Fellow Hemmi Roid, slide rule collector and Hemmi researcher. I had the pleasure to meet John a number of years ago and gave him a few slide rules as he was starting his collection.
  • Atsushi Tomozawa of Japan. Advanced Hemmi collector and authority; contributor to the OS Bulletin; avid aurora borealis observer, for which he travels the world.
  • Otto van Poelje of Hilversum, The Netherlands. Member of the Oughtred Society board of directors; leader of the Dutch Circle for Historical Calculating Instruments; frequent contributor to the OS Journal and to the OS Bulletin, which was his original idea for the OS to publish; creator of The Oughtred Society Award program; source of many new ideas for the Society.
  • Dieter von Jezierski of Germany. Expert on Faber-Castell slide rules; retired long time employee of Faber-Castell; frequent attendee of the Society’s west coast meeting, where I had the great pleasure to meet him and share a very enjoyable breakfast.
  • Tom Wyman of Palo Alto, California. Immediate past president of the Society, where he served in this position for 10 years; very advanced researcher and collector of 19th Century slide rules; prolific contributor to the OS Journal. I had the honor to visit with Tom in person at several OS west coast meetings and at the new winter meeting in Las Vegas in February 2008.

  • I hope you have enjoyed meeting these fellow slide rule enthusiasts as much as I have!

    There are indeed many benefits to participation in the Oughtred Society

Ted Hume