Demonstration Slide Rules
Used for Teaching Classes


These are enlarged versions of popular slide rule models that the manufacturers produced and provided to schools to aid in teaching the use of slide rules. They were excellent advertising tools for promoting the sales of the brand.

Note: Images included here were photographed, scanned from catalogs, submitted by collectors, or found on the web to document all the varieties that exist. My apologies if pictures are not properly credited. Let me know so I can better document everything.

One of the most comprehensive collections I've seen are located in the office of Radiologist Dr. 'Dalai' (nickname) in Columbia, South Carolina, graduate of Baylor University, who first posted these on his interesting blog .

Aristo/Faber Castell Schul-Rechenschieber

Shown are Aristo Junio, Aristo Bi-scholar,
Unknown, and Faber Castell 52/80

Pictures courtesy of Segeo.de
(Stephan Georgi) - Hamburg, Germany

This 120cmx40cm Aristo Tri-Log is from the
Tweed Library Archive (UK).

Aristo TriLog 308 Courtesy of Prof. Dr. Jörn Lütjens

Faber Castell Model 315-83N Novo Duplex Demonstration Slide Rule. Located At Powerhouse Museum.

This picture is from a 1954 Aristo (German) catalog.
Rechenschieber-Online-Museum (Ahrensburg, Germany)

Xu Guisheng in Shangia, China shows his Aristo teaching slide rule that obtained from a professor in Germany.

Courtesy of W. Girbardt University of Grifswald (Germany)

Aristo 203 Projection Rule for use in a Slide Projector. Projector model Lietz Prado is shown.


REF Early Dietzgen Demonstration Slide Rule
Early Dietzgen Demonstration Slide Rule
Made in Bavaria. Has Railroad Track style divisions
It appears to be a 4 foot long model.
Ebay Photo

REF 1760 Series Demonstration Slide Rule
1760 Series Demonstration Slide Rule
The 7 foot long 1760 Series Demonstration Slide Rule was equivalent to a Mannheim Type 1768, with scales A, [ B, CI, C ], D, K, and [ S, L, T ]
This one was owned by the IBM company and shows an asset tag.
Archive - Photo donated by Darryl Willis

Keuffel & Esser

K&E demonstration slide rules, with Mannheim scales, date back as early as 1930, when they appeared in the 1933 K&E catalogs as Model 100 and 101. (contributed by Clark McCoy). the slide rules were typically made of Redwood, which is lighter in weight than many other woods.

The 1936 catalog, although listing just the Model 100 and 101, has a note at the bottom of the page stating Demonstration slide rules, with the scales of the K&E Log Log Trig (equivalent to the 4080) and Log Log Decitrig Slide Rules (equivalent to the 4081), are also available.

The 1962 catalog, calls the 4053 Model 100 now as 69-1944, the 4081 Log Log Decitrig Slide Rules as 68-1923, and a new Demonstration Slide Rule for the Decilon 68-1100, called Model 68-1929 is now available.

1933 K&E Catalog

1936 K&E Catalog

1962 K&E Catalog

1967 K&E Catalog

Model (Unknown)- Mannheim Type , 7ft 1/2in long

This Demonstration Slide Rule was found by Monroe Postman and is unique. Although it looks like a Model 100 it is missing the K scale on the lower face. This may be a match to a K&E 4053 prior to 1926 when the K scale was on the bottom edge instead of on the face. Scales A, B, CI, C, D, S, L and T.

Model 100, 68-1944 - Mannheim Type , 7ft 1/2in long

The model 100 was equivalent to a 4053-3, with scales A, B, CI, C, D, K, S, L and T. By 1962 it was called Model 68-1944.

Model 101 - Polyphase Duplex, 7ft 10-3/4in long

The model 101 was equivalent to a 4070-3, with scales DF, CF, CIF, A, B, CI, C, D, K, S, L and T. It was not mentioned in the 1962 catalog

This Model was found on Flickr belonging to the cousin of Mark and Bert.

Model 68-1923 - Log Log Duplex Trig, 8ft

The model 68-1923 was equivalent to a 4081, with front scales: LL02, LL03, DF, CF, CIF, CI, C, D, LL3, LLL2. Back scales: LL01, L, K, A, B, T, SRT, S, D, DI, LL1.

Mike Konshak collection www.SlideRuleMuseum.com

North Carolina State University School of Mathematics
John Wesley Cell, NSCU, 1960

Model 68-1929 - Decilon, 6ft long

This model was equivalent to the Decilon 68-1100/68-1130, with front scales: Sq1, Sq2, DF, CF, CIF, L, CI, C, D, Ln0, Ln1, Ln2, Ln3. Back scales: Ln-3, Ln-2, Ln-1, Ln-0, A, B, T, SRT, S, C, D, DI, K.

Scans courtesy of Clark McCoys K&E Catalogs

Above Pictures courtesy of Sphere Research

Col. Seeley (USAF) points to K&E Decilon in his office in the Mathematics Department at the US Air Force Academy, Colorado Springs, CO. Decilons were standard issue from 1967-69. Post Versalogs were issues before and after that time. Picture courtesy of Fred Malmstrom, NMI Civ USAFA/CWCH.

Pickett Trainers

Pickett 4ft and 7ft slide rules are the most abundant and varied that one can find. They were made of plywood with sheet aluminum bars holding the stock together. Pickett gave one to every school that ordered 24 standard size slide rules, consequently doing a great job of placing free advertising in every school in America.

From the Pickett Wall Mount Teaching Guide by Maurice Hartung

Down load the 48 page teacher's guide
Pickett Teaching Guide (17.7MB)

Model 2 (circa 1945) - 7 ft

Dagmar's class photos by Craig Kielhofer ISRG

Model 500-ES - 4 ft

Mike Konshak collection www.SlideRuleMuseum.com

Model N803-ES Speed Rule - 7ft

Model 902-ES Trig - 4ft

Model 1010-ES - 7 ft

Donated to www.SlideRuleMuseum.com by Tom Grosh (on right), now located at the Computer History Museum. Notice another Pickett Trainer, a 4ft 500-ES reflected in the mirror with hoards of slide rules in the lower right corner.

Donated to ISRM by Thomas Corby (on right). Tom wrote: " I acquired the slide rule about 40 years ago from a friend in Pottsville, Pa. (My Birthplace). I was attracted to it since it was identical to one used at Indiana Institute of Technology in Ft. Wayne, IN where I obtained a BSME in 1959. "

Model N4-ES - 7ft

Courtesy of Ken, CEO, Acorn Product Development
This is mounted in their office in Fremont, CA

N1010-ES Trig Details


Hemmi Model 101 - 48 inches x 10 inches

Sitting in ODELCO factory in the Phillipines.

Pictures courtesy of Oscar de Leon, president of ODELCO

Model 1447D - Student, 4ft

The model 68-1923 was equivalent to a 1447, with front scales: A, B, CI, C, D. On the back was S, L, T.

Courtesy of Paul Ross The Slide Rule Trading Co

Model 1447DA - Student, 6ft

The model 1447DA was equivalent to a 1447, with front scales: A, B, CI, C, D. On the back was S, L, T.

Courtesy of Paul Ross The Slide Rule Trading Co

Model 1460 Versalog - Student, 7ft

The model 1460 was the most advanced Post Slide Rule, with Front Scales: LL/1, LL/2, LL/3 [ T/T, SecT/ST, Cos/S, C ] D, LL3, LL2, LL1 and Back Scales: LL0, LL/0, K, DF [ CF, CIF, CI, C ] D, R1, R2, L

This one found its way into Peter Owen's hands in the UK

Hemmi Model 260 - 5ft

Collector Amedeo Muscelli, found this  in a local Venezuelan shop. The 5 foot overall Hemmi 260 slide rule is made of wood and painted with an air brush using a template. The cursor is a one sided frame with a wire in the middle, this frame work hooked onto the top of the rule and had to be re-hung when the rule was reversed.

Pictures courtesy of Sphere Research

W.M. Welch Manufacturing Company, Chicago

Welch demonstration slide rules were made of 3 layers of masonite boards that were riveted together with five rubber feet on the back, for desk top manipulations. They are the only training slide rules with a black background and white scales. There are two known models, the most common have the divisions boxed in a 'railroad track' scheme, which was popular in pre-1940 slide rules. The second model has modern divisions as shown in the following photos. The modern scale divisions seem rarer than the boxed scales as the only one that has been found is here at ISRM. It is not known which is the earlier version. Very few models are found with original cursors and the model at ISRM has a replicated version made by the curator.

Material: painted Masonite,, multilayer boards
Front Scale: A [ B, C ] D
  • Overall length: 47 -3/4"
  • Width of stock: 8-3/4 to 9"
  • Width of slide face: 3-1/2 - 3-3/4"
  • Width of slide tongue: 4"
  • Thickness of lamination stack: 5/8"
  • Thickness of top face (with scales): 1/8"
  • Thickness of slide spacer: 1/8 to 3/16"
  • Diameter of finger pocket: 1" (some are through holes, others are pockets, cut just in the top layer. Through holes could hurt your finger if you moved it too fast to one side).

Students Study Physics Clark College, Atlanta.Welch Demonstration Slide Rule On Blackboard. c1950 Getty Images. Note: Cursor design.

Welch - 4ft Standard Divisions

ISRM Collection

Welch - 4ft Boxed (RR Track) Divisions

Most of these pictures were found on eBay.

Williamsport War Models

Williamsport War model Demonstration Slide Rule


  • Overall length: 92"
  • Width of stock: 7"
  • Width of slide face: 3-1/2"
  • Width of slide tongue: 4-1/4"
  • Thickness of lamination stack: 1-1/8"
  • Thickness of top face (with scales): 3/8" (This appears this may made of three 1/8" laminated pieces.)
  • Thickness of slide spacer: 1/4"
  • Diameter of finger pocket: 3/4"
  • Weight: ~30 lbs.
Material: Painted Masonite
Front Scale: A [ B, CI, C ] D

John Samson, PhD, writes: "I attended the Illinois Institute of Technology (IIT) in Chicago, IL from 1966 to 1970. One of the IIT Homecoming events in December 1969 was a Slide Rule contest, which I happened to win. My prize for winning the contest was an 8-foot long Willamsport War Model slide rule. When I inquired about the source and origin of the slide rule, I was told it was found in the basement of Siegel Hall (at that time home of the Physics and EE Departments) and, reportedly, it was used to train navigators and pilots at IIT during World War II. The slide rule is made out of pressed-board/Masonite.". Note Illinois Institute of Technology (Illinois Tech or IIT) is a private research university in Chicago, Illinois. It was established from the merger in 1940 of Armour Institute and Lewis Institute.
John (in left photo holding slide rule) received his BSEE from IIT (1970), two degrees from MIT (Massachussettes Institute of Technology) SMEE (1972) and EE (1973), and his PhD (1992) from USF (University of South Florida). He used a K&E Decilon during school. John spent his entire career in industry and has been a part-time faculty at several universities along with being a guest lecturer at various universities. John is currently a Research Affiliate at MSU (Morehead State University).
Prof. Harris Lecture On Slide Rules, Mentions LARGE Slide Rule. Armour Tech News March 1, 1938 Prof. Harris Lecture On Slide Rules, Mentions LARGE Slide Rule. Armour Tech News March 8, 1938 Slide Rule Course announcement, mentions Large Scale Slide Rule. IIT Tech News Oct 5,1951 Slide Rule Course announcement, mentions Large Scale Slide Rule. IIT Tech News March 21, 1952

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