Steve's Slide Rules

What's New or Updated


Questions and Mysteries---

- (3-13-24) Does anyone have a good idea who actually manufactured this Hungarian Military Pilot's Flight Rule? Its structure and design look very familiar and it seems I ought to be able to identify its manufacturer, but I can't quite place it.

- (10-6-23) The rule I had initially described as a Hemmi 44 remains a mystery. It is certainly not any variant of a Hemmi 44. Unfortunately, I do not yet see that it is terribly similar to any example provided in Paul Ross's excellent Hemmi Catalogue Raisonne. If anyone can provide any guidance, I would appreciate the help! Thanks!

12-21-24

- Added a BRL P1943 Hydraulic Slide Rule for Weirs, Notches, and Orifices.

12-18-24

- Added a BRL P3188 Paper Calculations Slide Rule - Metric Units.
- Added an Aristo 90103 Universal Slide Rule for Calculations Used in Wire Drawing Processes.

11-19-24

- added a Diwa 111 Electro.

11-12-24

- added a PIC 111 Rietz

10-29-24

- Added a Cox & Stevens E-1092 Load Adjuster for the Boeing B-52C & D Stratofortress.
- Added a SIDA Earth Parameters Measurement Slide Rule.
- Added a SIDA Vibration Measurement Slide Rule.
- Added a Westinghouse SA-7063 Steam Condenser Calculator.

10-18-24

- Added cover image and Table of Contents for "The Slide Rule in Everyday Use" , by Alan B. Dobson, Blundell Harling Ltd., 3rd Impression 1973, 86 pp.

10-5-24

- Added a Shanghai Open Channel Hydraulic Slide Rule.
- Added a Tianjin 6506 Log Log Duplex-type.

9-25-24

- Added a Tianjin Huge Elephant Log Log Duplex Vector-type.
- Added a Ding Feng 5571 Log Log Duplex Hyperbolic-type.
- Added a Quifan 5891 Log Log Duplex Vector-type.
- Added a Xueshi 408 Hyperbolic Log Log Duplex-type.
- Added a Shanghai Hezhong Log Log Duplex Vector-type.
- Added a Shanghai 57 5" Simplex.

9-15-24

- Added a Tapalow Heat-O-Meter/Radiometer Slide Rule.
- Added a Faber Castell 12/82 Precision Slide Rule.
- Added a F. C. Farmar's Standard Slu]ide Rle for the Entire Wine & Spirit Trade, Desk Size.

8-1-24

- Added a Blundell Omega 402 Log Log.
- Added a Blundell Harling Academy Duplex 502.

7-23-24

- Added an EasyR Hydraulic Slide Rule.
- Added a Fearns V-Belt Horsepower Calculator.

7-18-24

- Added a James Farrow Pilot Balloon Slide Rule Mk I Slide Rule.
- Added a BRL Academy Series 306 Tarrant Hydraulic Slide Rule.
- Added a Nestler 27 Prazision.
- Added a Blundell Harling Type D.26 Darmstadt.
- Added a Blundell Harling E.25 Electro.

6-29-24

- Added a Hiltpold Semi-Circular Slide Rule.

6-28-24
- Re-arranged the 'Specialty Rules' section a little bit. (just the hard-coded HTML page; the Python-generated HTML page hasn't yet been changed to match the hard-coded one.

6-26-24

- Added a Hemmi P141 Air Conditioning Duct Calculations 5".

6-23-24

- Added a Hemmi 254WS "High School Students".
- Added a Ricoh 155 Business Management Rule.

6-21-24

- Added a Loga 15M Cylindrical Slide Rule.

5-28-24

- Added an Aristo 10155 Soil Swell Pressure Slide Rule.
- Added a BRL P2361 Westechno Exmouth Westec Electronics Slide Rule.
- Added a Jiangshi Type-B Hyperbolic.
- Added a Ricoh 1051 S Engineering Rule.

4-24-24

- Added a Unique Pioneer Long Scale Rule.
- Added a Logarex 27406 Finlog.
- Added a Pickett Model 8 McGann Industries Variable Density Flow Computer.

3-13-24

- Added a Hungarian Military Pilot's Flight Rule.

3-12-24

- Added a Union Instrument Corporation Photo Interpretation Kit - Pocket Type.

3-1-24

- Added cover image and Table of Contents for "Working With A Slide Rule, a programmed learning text" , by Geerts, W. (trans by C. Van Walraven), Brandon/Systems Press, Princeton, NJ, 1969, 39 pp.

2-28-24

- Added a BRL P4366 EMEFCO Ultrasonic Slide Rule, M. Falk & Company Ltd.
- Added a Cox & Stevens E-604 Load Adjuster for the Consolidated B-24 and PB4Y-1 Liberator.
- Added a Precision Scale Inc. Air Force Aerial Photo Rule Type A-1.
- Added a Staedtler-Noris 54452 Log Log.
- Added a Stanliand Pipeline Slide Rule.
- Added a W. A. Thomas Universal Hydraulic Sliderule.

2-7-24

- Added a UTO 901 Darmstadt.

2-2-24

- Added a SIDA 1098 Electro.

1-10-24

- Added a Mear Water Flow Calculator for Bitumen Lined Steel Pipes.

1-8-24

- Added a Boots Ringplan Precision Log Log Slide Rule.

12-10-23

- Added a AcuMath 1311 Log Log Decimal Trig (Yellow over Magnesium).

12-6-23

- Adde3d a Blundell Harling Academy 302 Log-Log, 2nd Version.
- Added a SIDA Ruyi 6202 Log Log Duplex Trig.
- Added a Xuesh 6171 Hyperbolic Log Log Duplex.

11-17-23

- Added a K&E 4094 Merchant's Slide Rule

10-30-23

- Added a Graphoplex Weight of Steel Pipes Slide Rule.

10-26-23

- Added a Aristo 956 Bildflug Photogrammetry Slide Rule.

10-24-23

- Added an IWA 1638 System Wern ABC Circular Slide Rule.

10-10-23

- Added a Norton & Gregory Time/Rate Slide Rule.

10-3-23

- Added a Ding Feng 5751 Log Log Duplex Hyperbolic.

9-21-23

- Added a Haenni Humidity-Temperature Calculator.
- Added a Thornton 0552/1448 Speed-Time-Distance Nautical Slide Rule.
- Added a Cox & Stevens E-1000 Load Adjuster for the Convair B-36D Peacemaker.
- Added a Unique Harfield Weight Calculator

9-11-23

- Added a Concise Stadia Slide Rule.
- Added a Hemmi Denkishoin Electronics Engineering.
- Added a Hope 65 Closed Form Simplex Log Log.
- Added a Hungarian Military Radio Tuning Aid.
- Added a Perrygraf EG&G Judson Infrared Radiation Calculator.
- Added a SIDA Ruyi 1083.
- Added a Thornton? Clementson Steam Pipe Sizing Slide Rule.

7-11-23

- Added a Aristo 90126 Hydraulic Pressure Loss Slide Rule.

7-3-23

- Added a Dietzgen 1759-B Mannheim Phillips.

6-20-23

- Added a Blundell Blakeborough Valve Sizing Rule.
- Added a J. B. Carroll Type MB-2A Navigation and True Air Speed Computer.
- Added a K&E 68-1434 Log Log Duplex Vector.
- Added a Heath & Co. Hezzanith Carmody Navigational Slide Rule

6-13-23

- Added a BRL P3259 Wavin Pipe Friction Computer.

6-5-23
- Added a Simplon Major Log Log.
- Added a Simplon Primary Log Log.
- Added a Gerber TP-007200B Variable Scale.
- Added a Fearns Power Factor Calculator and Slide Rule.
- Added an Aristo 918 Sewer Slide Rule, system Vicari.

5-18-23

- Added a Unique Dualistic High Speed.
- Added a Nestler 0234 Rietz.

5-6-23

- Added a Teledyne Post 1414 Beginners (Hemmi P280).

4-20-23

- Added a Bosch Cos-φ Calculator.
- Added a Donald Hedberg ChemPredictor.

4-15-23

- Added a Nestler Star Slide Rule and Reference Tables for Structural Engineering.

4-11-23

- Added a Bybee Voltage Drop Calculator for Distributed Impedance Loads.
- Added cover image and Table of Contents for "A Basic Slide Rule Manual" , by Young, Neville W., West Publishing Corporation Pty Ltd, Sydney, 1973, 86 pp.

4-9-23

- Added a Thornton P.I.C. P133 Differential Electro.

4-7-23

- Added a Slyd-Rul Elemental Slide Chart.
- Added a Hemmi 401 Coiled Spring Slide Rule.

4-1-23

- Added a Novotni Flat Rolled Slide Rule.
- Added a Pickett 4-ES Dual Base Log Log Reciprocal Scale (Vector Hyperbolic).

3-30-23

- Added a BRL P4843 Lummus Hydraulic Slide Rule.

3-28-23

- Added a Gregg TAD True Position Tolerance Comparator.

3-23-23

- Added a Teledyne 44CB-260, Hemmi P452.

3-17-23

- Added an Aristo 630 Chemie, System Dr. Buckle
- Revised description of the Aston & Mander Hannyngton Extended Scale Slide Rule.
- Added a Blundell Harling Super Duplex A505.
- Added a Magnameta International Petroleum Tonnage Calculator

3-13-23

- Added a British Slide Rule Company Supreme Slide Rule.
- Added a Graphoplex Pierre Gy Sampling Slide Rule.
- Added a Perrygraf Electro-Optics Infrared Radiation Calculator.

3-11-23

- Added a Thornton 172/PC17 Student's Log Log w/differential trig scales.
- Added a W&G 454 Dualface Artillery & Survey Model.

3-7-23

- Added a Perrygraf Westinghouse Power chek✓Up Calculator.

3-2-23

- Added a Diwa 541 Businessman.
- Added a Diwa 730 Combilog/
- Added a Royal Ecola Nr.1053.
\
2-23-23

- Added a Fuji 1200 01 Darmstadt Special Ex. 2

2-18-23

- Added a UTO 901U Real Nr. 2, System H-Croon
- Added a Lawrence Flashrule 6-0p

2-6-23

- Added Dietzgen Needham's Trig-Easy Tools

2-3-23

- Added a Propellor Properties Slide Rule - Unknown Origin

1-30-23

- Added a UTO 551U Electro.
- Added a Xylem Bell & Gossett System Syzer Hydronics Calculator

1-20-23

- Added a Flat Steel Novotni Weight Slide Rule.

1-17-23

- Added a Nestler 21a Darmstadt 20 inch

12-31-22

- Added a Faber Castell 157/89 Log-Log.
- Added a Blundell Harling 805 Electro, Example 2

12-29-22

- Added a Blundell? Paper Calculations Slide Rule

12-21-22

- Added an Aristo 10127 Bosig Compressor Rule.
- Added a Charles Bruning Log Log Duplex type (sme as Dieterich-Post 3072).
- Added a Omega DT-1015 (same as Relay 153 or Relay DT-1015).
- Added a Unique Universal I, 5 inch.

12-8-22

- Added a Hemmi Foxboro Flow and Valve Rule, Ex. 2

11-17-22

- Added a Cox & Stevens E-719 Load Adjuster for the Boeing B-29 Superfortress.

10-27-22

- Added a Diwa 341 Businessman Elegant.

10-22-22

- Added an Aristo 80107 Exhaust Gas Slide Rule.
- Added an IWA 06094 Atlas Copco Compressed Air Line Properties Slide Rule.
- Added an IWA 02114 Trilux Special LIghting Slide Rule.

9-24-22

- Added a Fuji 1250S Duplex LogLog.

9-7-22

- Added a Graphoplex 640, Electric Log Log Duplex, blank back, Example 3.

8-13-22

- Added a Blundell Harling 802 Log-Log.
- Added a Hemmi 70 Rietz 20 inch, Example 2.

8-11-22

- Added a Blundell Luton Type E.3. Electro.
- Added a Nestler System Landis & Gyr Electric.

8-6-22

- Added a Blundell Harling T.11 Technician's.
- Added a Cox & Stevens Load Adjuster for the Boeing B-25 Mitchell.

7-30-22

- Added a Reiss Elektro.

7-20-22

- Added a Thomlinson Equivalent Paper Slide Scale.
- Added a Blundell Harling Academy Duplex 904.
- Added a Logarex 4542-27402 Elektro.
- Added a K&E N4133 Roy Lance Electrician's Slide Rule.
- Added a Fearns Inertia Slide Rule.

6-28-22

- Added a Gordon Co. LogLog.

6-27-22

- Added a Blundell Harling AL6 Log Log.

6-23-22

- Added a K&E 4110 Mannheim Power Trig.

6-22-22

- Added a Blundell Harling T.12 Technicians.

6-13-22

- Added an AcuMath A-60 Log Log Decimal Trig.

6-8-22

- Added a Faber Castell 4/87 Rietz 50 cm.

6-6-22

- Added a Graphoplex 698 Electronics Engineering.

6-3-22

- Added a Novotni Paper Box Board Rule.

5-27-22

- Added a VEB Mantissa 1731 178 Masse (for density/weight caculations).

5-22-22

- Added a Logarex 27608 Premiant, System Dr. Pleskot.

5-6-22

- Added a Hemmi 70 Rietz 20 inch.
- Added a Fowler's Type RX Long Scale Calculator.
- Added a Patco Mark IV Log Log.
- Added an AWF 705 Change in Spring Length Calculator
- Added an Aston & Mander Hannyngton Extended Scale Slide Rule.

4-19-22

- Added an IWA 0432 Building Heat Requirements Slide Rule (according to DIN 4701)
- Added an IWA 0778 Herion Hydraulic-Pneumatic Slide Rule

4-2-22

- Added a Blundell Harling Humidity Slide Rule, Mk. 6A - Celsius.

3-30-22

- Added a K&E N9071-3 Doric Polyphase Duplex Decitrig.

3-21-22

- Added an Aristo 90125 Acetylene Slide Rule.

3-10-22

- Added a K&E Brick-O-Meter.

2-28-22

- Added a K&E N4101 Stadia Rule 20".

2-2-22

- Added an Aristo 939/n=10 Stahlbeton.

2-2-22

- Added a Dietzgen 1778 Redi-Log 5", Example 2
- Added a PIckett N1072-ES Spring Design Slide Rule for Connecticut Spring Co.

1-26-22

- Added a Precision Scale Inc. Model 1751 Log Log 10 Hyperbolic.

1-20-22

- Added an ITAB Antenna Attenuation Value Calculator.

1-18-22

- Added a Pickett 7-T Pipe Flows, Service Pipeline Company.

1-15-22

- Added a Pickett N902-ES Simplex Trig.

1-14-22

- Added a Precision Scale Inc. Spring Design Rule for Spring Engineers Inc.
- Added an Aristo 80102 Mobil Fuel Combustion Slide Rule 5".

12-30-21

- Added a Stanley Fuller Model 1.

12-18-21

- Added a K&E 4071-3 Polyphase Duplex Decitrig.

12-15-21

- Added a J. B. Carroll Spring Design Slide Rule for Associated Spring Corporation.

12-11-21

- Added a K&E 4088-3 Polyphase Duplex.

12-9-21

- Added an Aristo 90172 Slide Rule for Pipeline Calculations.
- Added an IWA 0257 Slide Rule for Radio Technicians.

11-2-21

- Added a Logarex 27602 Log Log Duplex.

10-29-21

- Added a U. S. Army Air Force Line of Sight Indicator C-544-2, Mitchell Field, NY

10-28-21

- Added a Hemmi 86/3K 5 inch Electro with Overrange.

10-17-21

- Added a Yokogama Electric Works Gas Slide Rule

10-12-21

- Added an Aristo 970E "Nobema" Multilog.
- Added a North American Aviation Matrix Rule.

10-3-21

- Added a Graphic Calculator Co Universal Soil Loss Erosion Calculator.
- Added a Fearns Belt Conveyor Calculator


10-1-21

- Added a Nestler 0320 Oilrule by Dr. Schmeling.

9-30-21

- Added an Aristo 0903 LL Scholar - Capitol Radio Engineering Institute

9-14-21

- Added an Aristo 40140 Steel Mesh Reinforced Concrete Calculations (Baustahlgewebe-Listenmatten).

9-1-21

- Added a Deeva 720 Polylog.

8-28-21

- Added a DAYCO A-3375 DAYCOLOG II V-Belt Drive Fatigue Analyzer.

8-20-21

- Added a Pickett 550-T Warren-Knight Weight Rule No. 1373-ET.

7-20-21

- Added a Dietzgen 1750 Maniphase.

7-11-21

- Added a Logarex 4542-27403 Darmstadt.

7-9-21

- Added a Hemmi 64T Super-Rietz.

7-6-21

- Added an AcuMath 1300T Log Log Decimal Trig (yellow).

6-30-31

- Added a Concise Sama & Etani CIBA Medical Tables and Calculator.

6-28-21

- Added a K&E 4168 Polyphase Duplex 5".

6-12-21

- Added a Ricoh 153 Engineering Rule.

6-11-21

- Added cover image and Table of Contents for "How To Use a Slide Rule" , by Sackheim, George, Harper & Row, 1964, 83 pp..

6-9-21

- Added a Hemmi P37 Sales Slide Rule.

6-1-21

- Added a Jakar No. 1011 Log Log.

5-19-21

- Added an Aristo 967 Darmstadt.
- Added a BRL Met. Office M2260 Mk VI Humidity Slide Rule, Met. Ref. No. 22000.
- Added a BRL Alexander Slide Rule for Pipe Weights and Strengths.
- Added a Hemmi 44? Mannhein-type with 'C'-style cursor.
- Added a K&E 4081-3 253284, Scale Set #6 with magnifier.
- Added a Loftus Alcohol Proofing Double Slide Rule.

4-2-21

- Added an Aristo 1067U Darmstadt, 20".
- Added a Thornton P271 Log Log.

-6-21

- Added a Concise Sama & Etani Circular Slide Rule and Conversion Tables, Gulfgas.

3-2-21

- Added cover image and Table of Contents for "The Slide Rule Applied to Commercial Calculations" , by Shireby, R. M., Isaac Pitman & Sons, London, 1922, 66 pp..

2-12-21

- Added a Berger Scientific Supplies C2165 Log Log Decimal Trig.
- Added a Faber Castell 1/48 Maschinenzeit.

2-11-21

- Added cover image and Table of Contents for "The Slide Rule (a Romanian language pb)" , by Irimescu, I., Editura Tehnica, Bucharest, 1978, 112 pp.

2-6-21

- Added a PIckett 1011-ES Trig Exponential Speed Rule.

2-5-21

- Added a Perrygraf Feild's Hydraulic Calculator, based on Manning formula.

2-2-21

- Added cover image for "The Slide Rule - An Elementary Treatise", by Clark, J. J., The Technical Supply Company, 1st Edition. 1909, 62 pp.

1-25-21

- Added a Faber Castell 57/89 Log-Log.

1-16-21

- Added a Charles Bruning 2420 Mannheim Polyphase-type.

12-30-20

- Added a Concise Sama & Etani Reference Tables & Circular Slide Rule, Sylvania Lighting Products Group, Model GTE-1.
- Added a Faber Castell 3/11 for steel & concrete calculations.

12-15-20

Added a Hemmi Hydraulic Slide Rule.

12-14-20

- Added a Faber Castell 111/66 Demegraph, System Schirmer

12-3-20

- added a Cox & Stevens Load Adjuster for the Boeing B-17 Flying Fortress.

11-6-20

- Added a British Slide Rule Company Technical Aeronautical Slide Rule, Example 2.
- Added a PIC 101 Simplex.

10-14-20

- Added a Cox & Stevens Load Adjuster for the Boeing B-29 Superfortress.
- Added a Jakar No. 29 Student Log Log

10-1-20

- Added a C-Thru S-889 Log Log Duplex.

9-28-20

- Added a Concise Mallinkrodt Radiological Tables and Circular Slide Rule.

9-12-20

- Added a Cox & Stevens Load Adjuster for the Boeing B-47E.

8-26-20

- Added a Meissner KG Trim

8-10-20

- Added a Hemmi 157 General Engineering w/Log Log scales.

8-8-20

- Added an Aristo 930 System Beck Textile Rule.
- Added a Novotni Time Slide Rule.

8-6-20

- Added an IWA 0628 Control Valve Calculations Slide Rule.

7-15-20

- Added a Dietzgen 1725 Microglide Vector Type Log Log.

7-9-20

- Added a Gamma 2503 Budapest (same as Logar 2512).

6-29-20

- Added a Fuji 1201 Yamayo Tape Measure Correction Slide Rule.

6-24-20

- Added a BRL P3065 Bedford Truck Body & Payload Weight Distribution Rule.

6-19-20

- Added a Faber Castell 57/74 Textile Slide Rule, System Schirdewan.

6-15-20

- Added a Perrygraf Payne Residential Heating & Cooling Load Calculator.

6-11-20

- Added a K&E Associated Spring Corp. Belleville Spring Washer Computer.

6-5-20

- Added an Aristo 80126 Special Slide Rule for the Optical Workshop 5"

5-23-20

- Added a Faber Castell 342 Columbus, System Rohrberg Commercial Slide Rule, Variant 2.

5-6-20

- Added cover image and Table of Contents for "Electronics and Your Slide Rule, Parts I-IV", by Geiger, Darrell L., Cleveland Institute of Electronics, 3rd Edition, 2nd Revised Printing, 1965, Part I-29 pp, Part II-58 pp, Part III-88 pp, Part IV-128 pp

5-2-20

- Added a Nestler 0260 Mecanica.

4-19-20

- Added a Dietzgen 1773 Pocket Darmstadt 5".

4-11-20

- Added a Tektronix Tek-003-023 Circuit Computer.

4-10-20

- Added a BHL P4277 Nelson-Jones Circuit Designers Slide Rule.

4-7-20

- Added a Loga 30 T t duplex Log Log Circular Rule.

3-31-20

- Added a Faber Castell 67/98b Elektro.

3-25-20

- Added a BRL P2808 Sandt Ultrasonic Slide Rule.

3-23-20

- Added a BRL P1454/2 Mk II Slide Rule for Calculation of Diameters of Orifice Plates With Corner Taps.

3-18-20

- Added a Unique Slide Rule for Tube Making and Deep Drawing

2-7-20

- Added a Hemmi P402 Corporate Performance Analysis, Manufacturing Businesses.

2-6-20

- Added an AcuMath 400 Simplex Trig.

1-22-20

- Added a Tehnolemn Electrotehnica (Electro-type slide rule).

1-11-20

- Added cover image and Table of Contents for "Understanding the Slide Rule", by Hocking, A. J., Coles Publishing Company, Ltd., 1974, 114 pp.

1-6-20

- Added a K&E 4138 Morrison's Radio Engineer's Slide Rule.

12-30-19

- Added a K&E 4175 Psychrometric Slide Rule.

12-11-19

- Added a VEB Mantissa Feutron Klima 1802 Humidity/Moisture Content Calculations, 2nd Example.

12-10-19

- Added a Thornton P.I.C. 121 Differential Electro.

12-5-19

- Added a Concise Sama & Etani Reference Tables & Circular Slide Rule, Nalco Pulp and Paper Chemicals, Model NA-1.

12-2-19

- Added a Dietzgen 1757 PrimaTrig.
- Added a Mear Domestic Central Heating Calculator.

11-23-19

- Added a U. S. Army Log Log Slide Rule.

11-18-19

- Added a Lawrence Engineeering Services F. M. Coverage Calculator

10-23-19

- Added a Compass SR-909.

10-9-19

- Added a (possible) Lawrence Molecular Ratio Slide Rule (for Portland Cement calculations?).

10-5-19

- Added a Diwa 311 Electro.

10-4-19

- Added cover image and Table of Contents for "Slide Rule in Electronics", by Carper, Don, Howard W. Sams Co., 1st Ed., !st Printing, 1967, 160 pp.

9-25-19

- Added a Hemmi 642T Improved Rietz - Ahrend.

9-23-19

- Added a Ricoh 1053-1 Engineering Rule.

9-18-19

- Added a Perrygraf Pratt & Whitney Gas Turbine Computer.

9-14-19

- Added a Nestler 0291 Polymath Duplex (metal end braces).

9-12-19

- Added a Faber Castell 2/31 Stahlbeton.

9-5-19

- Added a Flying Fish Product Quality Management Slide Rule.
- Added a Flying Fish Ultrasonic Probe Slide Rule.
- Added a Faber Castell 8/168 Mobil Viscosity Slide Rule.

8-26-19

- Added a BRL P1614 TEENI Soil Density Slide Rule - Clockhouse Engineering Ltd.

8-22-19

- Added a Faber Castell 111/38 Tachymeter 400g.

7-31-19

- Added review of "The Slide Rule, A Practical Mamual", by Charles N. Pickworth, Pitman & Sons Ltd, London, England, 1930, 19nd printing, 134 pp.

7-29-19

- Added review of "The Slide Rule and How to Use It", by Charles Hoare, The Technical Press Ltd, London, England, 1953, 22nd printing, 104 pp.
- Added review of "The Use of the Slide Rule", by F. A Halsey, D. Van Nostrand Company, New York, 1903, 3rd Edition, Corrected, 84 pp.
- Added review of "Solution of Raiload Problems By the Slide Rule", by E. R. Cary, D. Van Nostrand Co., New York, 1913, 136 pp.
- Added review of "Blaine's The Slide Rule As An Aid in Calculating", ed. By A. T. J. Kersey, F. & F. N. Spon, Ltd., London, 7th Edition, Revised, 1952, 124 pp.

7-25-19

- Added an Infrared Industries, Inc. Infrared Slide Rule.

7-20-19

- Added a Concise Sama & Etani Conversion Tables & Circular Slide Rule, Baroid Division NL Industries, Model NL-1, Insert NL.

7-10-19

- Added an Aristo 958 Geodat (360°).
- Added cover image and Table of Contents for "Slide Rule Fundamentals", by Sidney Messer, Polaris Publishing Company, Sausalito, CA, 2nd printing, 1959, 42 pp.

7-6-19

- Added a K&E 4100 Stadia Rule.

6-19-19

- Added a Blundell Harling Academy 302 Log-Log.
- Added a BRL N52 Janus Series Navigator's Dual Face Slide Rule, Ex 2.

6-13-19

- Added a Staedtler-Mars 54408N Log Log Duplex.

5-30-19

- Added a Hemmi 275D Expert Electrical Engineer 20".

5-27-19

- Added a Concise Sama & Etani Mobil Lubricants Circular Slide Rule & Viscosity Conversion Factors.

5-21-19

- Added a Norma Mercuria 190.

5-7-19

- Added a Concise Sama & Etani Circular Slide Rule & Conversion Tables, Gustav Hirsch Organization, Inc.

4-19-19

- Added a BRL P.G. 54 Photogrammetry Slide Rule.
- Added a Fearns Circular Slide Rule & Trigonometric Calculator

4-15-19

- Added a Graphic Calculator Co Water Treatent Calculator.

4-11-19

- Added a Concise Sama & Etani Reference Tables & Circular Slide Rule, Dresser Magcobar, Model MAG-1.

4-10-19

- Added an Instrumentation Laboratories Inc. Blood Acid/Base Calculator.

4-9-19

- Added a PIckett N1090-ES Connor Spring Slide Rule.

4-8-19

- Added cover image and Table of Contents for "The Slide Rule As An Aid In Calculations", by Blaine, Robert Gordon, ed. By A. T. J. Kersey, F. & F. N. Spon, Ltd., London, 7th Edition, Revised, 1952, 124 pp.
- Added a S-M 544LL AV Overhead Projector Slide Rule

4-5-19

- Added cover image and Table of Contents for "The Use of the Slide Rule", by Halsey, F. A., D. Van Nostrand Co. NY, 1903, 3rd Edition, Corrected, 84 pp.

4-3-19

- Added a Concise Sama & Etani Science Tables & Circular Slide Rule, Model 600-ST.

4-2-19

- Added a Aristo 965 Commerz II.

3-2-19

- Added a Beacon 315 Hyperbolic.
- Added a Ding Feng 5810 Log Log Duplex Hyperbolic.
- Added a SIDA Ruyi 1002.
- Added a SIDA Ruyi 6201.

2-20-19

- Added a Hemmi P267 Structural Design.
- Added a Ricoh OD-151-D Engineering Rule.

2-14-19

- Added a VEB Mantissa 1731 523/4 Darmstadt II.

1-30-19

- Added a Blundell Harling Academy Duplex 905.
- Added a Concise Sama & Etani Reference Tables & Circular Slide Rule, Dresser Atlas Division, Inc., Dress Industries Inc, Model DA-2.
- Added a Hemmi 279 Mechanical Engineer 20".

1-28-19

- Added a Concise Sama & Etani Conversion Tables & Circular Slide Rule, Dow Chemical Company, Model CTCS-552.
- Added a Relay 157.

1-27-19

- Added an Aristo 0906 LL BiScholar.
- Added a Data Chart Corp. ADEL Division, De Laval Turbine, Conversion Factors and Circular Slide Rule.

1-22-19

- Added a Hemmi 274 General Engineering Rule.

1-19-19

- Added a Concise Sama & Etani (Hydraulic) Conversion Tables & Circular Slide Rule, Continental Pipe Line Company, Model CP-1.

1-18-19

- Added an Olson TL-472 Electro.

1-17-19

- Added a Boots Ringplan Log Log Duplex Slide Rule.

1-16-19

- Added a Sillcocks Miller AT&T Guy Rule.
- Added a Sillcocks Miller RHM Fluid Power Calculator.
- Added a Spirule Company Spirule.
- Added a Concise Electronic Tables Circular Slide Rule, EE-112.

1-10-19

- Added a Koh-I-Noor 10010 Techno-Log.

1-9-19

- Added a Nestler 0254 Delta.

12-21-18

- Added a Diwa 511 Elektro.

12-15-18

- Added a Fearns Circular Slide Rule.

12-14-18

- Added a Flying Fish 1009 Hyperbolic Log Log Duplex.

12-7-18
- Added an Allegheny Plastics Inc., Illinois Coil Spring Company Slide Rule.
- Added an IWA 0594 Psychrometer and Humidity Slide Rule.
- Added a SeeGee Solutions, Center of Gravity Calculator for Pilatus 12-45

12-3-18

- Added a Nobema "Durer" 5970 (Log Log type).
- Added a Coleman J. Major Liquid Flow Slide Rule.

11-29-18

- Added a Graphic Calculator Co Boeing 727 Weight and Balance Calculator.

11-27-18

- Added a Richardson Pantocrat, Example 2, with 4 slides.

11-19-18

- Added an Abbot Brown Isotope Calculator, A.E.R.E. Harwell.
- Added an Abbott Brown Isotope Handling Calculator No. 1, A.E.R.E. Harwell.
- Added a Perrygraf Giannini Controls Corporation Radiation Dose Guide.
- Added cover image and Table of Contents for "Systematic Slide Rule Technique", by Allan, R. G., Isaac Pitman & Sons Ltd., 1962, 126 pp.

11-6-18

- Added a Compass 1325.

11-1-18

- Added a Radium Chemical Company Radium Exposure Calculator 1948.
- Added a Francis T. Miles Heat of Vaporization Indices Nomograph.

10-31-18

- Added a British Slide Rule Company Technical Aeronautical Slide Rule.
- Added a Thornton P144 A. C. Electrical, Example 2.
- Added a Staedtler-Mars 54401 Darmstadt.
- Added a Gerber TP-007 Variable Scale.

10-20-18

- Added a Fuji 1250 Duplex LogLog.

10-14-18
- Added a Faber Castell 1/38 Tachymeter.
- Added a Lietz Stadia Computer No. Lietz 3626-25.
- Added a Pickett 111-ES Circular.
- Added a U. S. Army Model M1 Slide Rule for Solution of Triangles.
- Added a Brown Boveri Motor Slide Rule.

10-12-18

- Added a Mear Industrial Central Heating Calculator.

10-9-18

- Added a Blundell Omega 407 Technico.
- Added cover image and Table of Contents for "The Slide Rule", by Young, Warren C., & Niederkorn, Donald N., USAFI, Madison, WI, 1962, 91 pp.

10-4-18

- Added a Relay 158.

10-1-18

- Added a Mear Gas Flow Calculator for Cast Iron & Steel Pipes, Model G4 - Imperial.
- Added a Mear Helical Spring Calculator.

9-28-18

- Added cover image for "The Slide Rule Simplified", by Richardson, G. W. , and Clarke, J. J., Technical Supply Company, Scranton, PA, Seventh Edition, 1918., 100 pp.

9-27-18

- Added a Lawrence 10-G Cutting Speed Calculator.

9-19-18

- Added an Aristo 0903 LL Scholar.
- Added a Loga Topo 6400 A o/oo Stadia Circular Rule.

9-14-18

- Added an Aristo 915E Elektro.
- Added a Meissner KG Galvanotechnik

9-12-18

- Added a Datalizer Loren Cook Duct Designer and Fan Law Calculator.

9-6-18

- Added a Fearns Tank Capacity Calculator.
- Added a BRL Radiac No. 1 Mk 2 Slide Rule for Radiation Exposure Calculations

8-31-18

- Added an Arth-O-Graf TECOM Antenna Calculator.

8-30-18

- Added an I.T.E. Circuit Breaker Co. Interrupting Capacity Calculator.
- Added a Perrygraf Collins Radio Space Systems Calculator.
- Added a Perrygraf KDI Pyrofilm Reflectometer Calculator.
- Added a Perrygraf TACO Parabolic Antenna Calculator.
- Added a U. S. Army Course and Distance Computer.
- Added a U. S. Navy Nautical Slide Rule, Mark 1, Mod 0
- Added a Graphoplex 641 System Log Log S.

8-25-18

- Added a Dietzgen 1798 Dempster RotaRule Model AA.

8-10-18

- Added a Dietzgen 1751 Maniphase Multiplex Industrial Type.

8-6-18

-Added a Nestler 0281 Geometer 400°.

7-23-18

- Added a Graphoplex 1614 System Log Log C.A.P.

7-2-18

- Added a Gurley Cox Stadia Computer.

6-21-18

- Added an A. G. Thornton K285 198Hg Wavelength Shifts look-up tool

6-16-18

- Added a Meissner KG Electric.

6-14-18

- Added a J. H. Weil Military Slide Rule Model 1917.
- Added an AML Mk IIIa Bygrave Position Line Slide Rule.

6-4-18

- Added cover image and Table of Contents for "The Conatruction and Use of the Slde Rule", by Paul Rood, Edwards Brothers Inc, Lithoprinters, Ann Arbor, MI, 1947, 94 pp.

6-2-18

- Added a VEMCO Model 171 Dyna - Log Log Hyperlog

5-26-18

- Added a Sandia Corporation Cumulative Binomial Distribution Computer

5-8-18

- Added cover image and Table of Contents for "How to Use a Slide Rule", by Heinke, Clarence H., Merritt Printing Co., Columbus, OH, 3rd Impression, 1958, 91 pp

3-30-18

- Added an Aristo 01068 Studio, 20" (w/T1 and T2 scales)
- Added an Aristo 01070 Multilog, 20"
- Added an Aristo Federfix 920 Computational Device for Cylindrical Spring Calculations
- Added a Somar Laboratories Spectro-Rule for X-Ray Spectroscopy

2-20-18

- Added a Hemmi P403 Corporate Performance Analysis Rule, Wholesale & Retail Distributors.

2-1-18

- Added a Diwa 913 (same as Diwa 914 but with a wooden core).

1-19-18

- Added a Perrygraf Probability Slide Rule, for Measurement Analysis Corporation

12-28-17

- Added an Aristo 90193 Bopp & Reuther Venturi Slide Rule

11-27-17

- Added a Pickett N7-T Pipe Flows, Service Pipeline Company.

11-24-17

- Added a Thornton P.I.C. 131/P.C. 18 Differential Electro

11-20-17

- Added a Graphoplex 630 Surveyor's Rule 400 g.

11-16-17

- Added a Staedtler Mars 544 DLL (log log duplex type).
- Added a Pickett N610-ES Log Log Speed Rule, Hydraulic Variant, American Pipe & Construction Co., 5"
- Added cover image and Table of Contents for "The Slide Rule (pb)", Erickson, H. T., Bruce Publishing Company, Milwaukee, WI, 1924, 32 pp.

10-18-17

- Added an H. R. Potter Raw Materials Calculator

9-17-17

- Added a Monarch SLR-5 (another rebranded Relay 150).

8-8-17

- Added a Ricoh 156 (Electronics type).

9-7-17

- Added a Graphic Calculator Co Boiler Efficiency and BTU Cost Calculator.

9-5-17

- Added a K&E 4058W Beginner's Slide Rule. It was a birthday present from my daughter-in-law! Thanks, Kristen!!

9-2-17

- Replaced a older, more worn, example of a Dietzgen 1733 Polymath Decimal Trig Log Log with a newer, cleaner version.

8-28-17

- Added a Pickett N808-T Standard Marine Fuels slide rule.

8-26-17

- Added a Fuji 552P Duplex Log/Log 5".

8-22-17
- Added a Graphic Calculator Co pH Calculator.
- Added a Graphic Calculator Co Chemical Predictor.
- Added a third, and cleaner, example of a K&E 4139 Cooke Radio Rule.

8-14-17

- Added a Nestler 0250 Multimathic.

8-9-17

- Added a Faber Castell 4/98 Elektro 20".
- Added a Meissner KG Viscorule.
- Added a Pickett N3-T Power Log Exponential Log Log Dual Base.

7-29-17

- Added an UTO 551U Darmstadt.

7-28-17

- Added a Hemmi 279D Mechanical Engineer 20".
- Added a Logarex 27601 Aviation Navigation Slide Rule LNP-56, Example 2

7-27-17

- Began what will no doubt be an agonizingly slow and tedious process of adding a listing of gauge marks to each slide rule description page. This is going to take forever. I wish I had just done it as I initially added the pages one by one.

7-15-17

- Added a Hemmi 201 4-Segment Duplex - 20".
- Added a Faber Castell 152/82 Schul-D-Stab

7-13-17

- Replaced an older, more worn example of a Logar Thermotechn 2512 Darmstadt with a newer, cleaner one.

7-10-17

- Added a Diwa 551-1 Darmstadt.

6-28-17

- Added an Aristo (Dennert & Pape) MHR1 Hohenrechenschieber.

6-26-17

- Added an Aristo 968 Studio.
- Added a Hemmi 64 Rietz.
- Added a Nobema "Durer" 5970P (Log Log type).
- Added a Post 1447 Improved Mannheim.

6-8-17

- Added a Stanley Complex Number Slide Rule.

5-16-17

- Added a VEB Mantissa Pilot's Slide Rule

5-13-17

- Added a Simplon Electro Log Log.

5-12-17

- Added a Hemmi 254W "High School Student's"

5-1-17

- Replaced older, badly discolored example of a Meissner KG Darmstadt. with a newer, cleaner example.

4-27-17

- Added a Ding Feng 5471 Log Log Duplex Hyperbolic.
- Added a Flying Fish Rubber Slide Rule - Shanghai Rubber Institute.
- Added a Flying Fish Humidity Slide Rule
- Added a Haiou Pai 6681 Log Log Duplex Hyperbolic (for Aeronautical Engineers)
- Added a Tianjin 6508 Wireless and Electro-Technician (5" version of 6504)

4-21-17

- Added a K&E Short Base Triangulation Military Slide Rule.

4-19-17

- Added an Aristo 867U Darmstadt 5".

4-4-17

- Added a Flying Fish 1013 Aerospace rule.
- Added a Flying Fish 1018 Electrical rule.
- Added a Flying Fish 1200 Pocket Vector rule.
- Added a Flying Fish I-J Function rule.
- Added a Tianjin 4.5" pocket rule.
- Added a Tianjin 6504 Wireless and Electro-Technician rule.

3-25-17

- Added a Flying Fish 1017 Chemical Engineering.

3-24-17

- Added cover image and Table of Contents for "Slide Rule Manual", Bruce Alexander Simm, G. W. Green & Sons, Melbourne, AU, 194-?, 47pp.

3-23-17

- Added a Graphic Calculator Co Union Pacific Railroad Calc-U-Layer Slide Rule.

3-14-17

- Added a Concise Alpha 4300 circular slide rule.

3-10-17

- Added a Fearns Babcock and Wilcox Reactirule 5".

3-7-17

- Added cover image and Table of Contents for "Engineering Slide Rule Manual", Wilson, T. N., El Camino Cillege, Torrance, CA 1959, 110 pp.
- Added cover image and Table of Contents for "Logarithms and Slide Rule Work, Hill, T. H. Ward, Isaac Pitman & Sons Ltd, London, 1944, 32 pp.
- Added cover image for "Stanley's Slide Rule Instructions", Stanley, W. & Company 1930-40s, 24 pp.

3-4-17

- Added a Russian Pilot's Flight Slide Rule.

3-2-17

- Added a second, slightly different, example of a Novotni Weight Slide Rule.

3-1-17

- Added a Graphoplex Pressure Drop in Gas Lines slide rule.

2-3-17

- Added an Aristo 869 Studiolog 5".

1-28-17

- Added a Graphoplex Calcrude Oil Viscosity Slide Rule.
- Added a Logarex 27601 Aviation Navigation Slide Rule LNP-56.

1-23-17

- Added a Nestler 0210 Darmstadt.

1-18-17

- Added a Faber Castell 4/54 Darmstadt 50 cm.

1-11-17

- Added an Aristo (Dennert & Pape) Quadrat QR 41.

12-31-16

- Added a Boonshaft & Fuchs Direct Reading Frequency Response Slide Rule.

12-30-16

- Added an Aristo 109 Rietz 50 cm.

12-8-16

- Added a Schacht & Westerich System Cuntz.

12-7-16

- Added a Hemmi 130 Darmstadt.

12-6-16

- Added a Blundell Harling 805 Electro. This rule is missing its cursor, so it's not a completely useful rule, but I couldn't find any other picture of a BRL 805 on the web, so I added this one until a better one comes along.
- Added a W. H. Smith Log Log Trig, Example 2, with 'K' scale
- Added a Gerber GA-103 GraphAnalogue. I know this thing isn't a slide rule, but it is kind of cool and I wish I had had the use of one in graduate school.

11-30-16

- Added an Ecobra Cosmos 1711.

11-26-16

- Added a U.G.I. Contracting Company U.G.I. Gas Heating Value Computer.

11-21-16

- Added a Halden Calculex circular slide rule.
- Added a Nestler 21 Darmstadt.
- Added a PIckett Model N-1050 Fuller Traffic Slide Rule.

11-16-16

- Added a BRL N52 Janus Series Air Navigation (or Navigator's) slide rule

11-12-16

- Added a British Slide Rule Company Technical Standard Slide Rule.

11-4-16

- Added a Mear Rotoscale Circular Slide Rule.

10-24-16

- Added a BRL Janus Series JV 56 hyperbolic rule.
- Added a Gamma Pocket Artillery Slide Rule

10-6-16

- Added a Tehnolemn Politehnica (an Electro-type slide rule).

10-4-16

- Added cover image and Table of Contents for "HowTo Use the Slide Rule", Forum House Publishing Company, Toronta, CA, 1968, 100pp.

9-30-16

- Added a SIC 5510 Log Log Decatrig 5"; short version of SIC 1510.

9-28-16

- Added an Aristo 10072 Hazen-Williams Hydraulic Slide Rule.

9-27-16

- Added a BRL Vector Slide Rule.

9-26-16

- Added a K&E 4143 Kissam Stadia Rule.

9-21-16

- Added a Pickett 50-1 Gregor Lag Displacement Computer.

9-11-16

- Added a Nestler 27/a Precision (long-scale rule).

9-10-16

- Added cover image and Table of Contents for "Elementary Slide Rule", A. J. Semner, Hawthorne Club Evening School, Cicero, IL, 1948, 40 pp.

9-7-16

- Added a Aristo 80100 Steel Mesh Reinforced Calculations (Baustahlgewebe-Lagermatten) 5".
- Added cover image and Table of Contents for "The Slide Rule in Theory and Practice", by G. P. Rawlings, Percival Marshall & Co, Ltd., 1950, 127pp.

9-6-16

- Added a Guardian Multiphase Slde Rule for Checking Account Analysis.

8-26-16

- Added a Perrygraf Andrew Antenna & Propagation Computer.

8-25-16

- Added a K&E 4045 Mannheim 16".

8-24-16

- Added an American Slide-Chart Corp. Hydraulic Slide Rule.

8-18-16

- Added a Logarex 27203 Darmstadt 5"

8-12-16

- Added a K&E N4053-5 Mannheim (Polyphase).

8-10-16

- Added a Logarex 27402-III Elektro.

8-3-16

- Added a Whitehead & Hoag circular slidechart called the 'Simplex Wiring Computer'.

8-1-16

- Added a Diwa 710 Teknilog.
- Added a UTO 631U 5" (shortened version of UTO 931U).

7-25-16

- Added a second example of a PIckett Model 1084 Resistance Design Slide Rule. This one is solvent-damaged but has different scales and scale arrangements from the previous one.

7-22-16

- Added a C. T. Cooper & Sons, Baines No. 1 Slide Rule for Flamants Formula for Water Velocity in Cast Iron Pipes.

7-21-16

- Added a Graphic Firing Table, 155mm Howitzer, Illuminating Projectile, U. S. Army
- Added a Davis-Grinsted Complex Calculator Slide Rule

7-20-16

- Added a K&E 4031 Mannheim 5".
- Added a Graphic Calculator Co Stephenson-Pfahl Hardenability Slide Rule

7-18-16

- Added a Hemmi 80/1 Electro.

7-16-16

- Added a Diwa 141 Darmstadt.

7-14-16

- Added a BRL Radiac No. 1 Slide Rule for Radiation Exposure Calculations.
- Replaced an older, dirtier version of the VEB Mantissa Artillery Slide Rule with a cleaner, C4, version.

7-9-16

- Added a K&E N4102 Surveyor's Duplex slide rule.

6-27-16

- Replaced older, scratched, version of Pickett N535-ES Electronics Technician with a C2-C3 version.
- Added a Faber Castell 63/82 Biplex 5"
- Added a Ricoh 1051 SE

6-14-16

- Replaced my poor translation of the Czech instructions printed on the back of the Logarex 27730 Gas Pipeline Slide Rule
with an accurate version, provided by Zdenek Sustr, of Prague. Thanks very much Zdenek!

6-13-16

- Added a Russian Circular Slide Chart: Periodic Table Data.
- Added a Thornton P144 A. C. Electrical.

6-4-16

- Added an M. W. Kellogg Hydraulic Slide Rule.

6-3-16

- Added a General Dynamics Reliability Slide Rule,

6-2-16

- Added a K&E N4053-2 Mannheim (Polyphase) 8".

6-1-16

- Added a Nestler 0370 Electro.

5/26/16

- Added a Faber Castell 62/83 Castell Novo Duplex 5"

5-21-16

- Added a Felsenthal C-130B Take-Off and Landing Computer.

5-19-16

- Added a Nestler 37 Electro.
- Added new data on the Japanese Brass Slide Rule.

5-11-16

- Added a Hemmi 154 Electronic (with two cursors) for Expert Electrical Engineers.

5-5-16

- Added a Tecnostyl 40/D Darmstadt-type rule.

5-4-16

- Added a Pickett Model 6-T Statistical Quality Control (Aluminum) Slide Rule.
- Added a Logar Thermotechn 2512 Darmstadt.
- Added a Faber Castell 378 Elektro.

4-22-16

- Replaced partially broken cursor lens on K&E 4160 Chemist's Rule and replaced old images with new ones

4-16-16

- Added a Thornton AA 010 Comprehensive (same as PIC P221)
- Added better images of the Perrygraf Victoreen Health Physics Slide Rule

4-11-16

- Added a Kahl Scientific Instruments Culbertson Oceanograpic Slide Rule

4-4-16

- Added a Faber Castell 1/22/322 Disponent.
- Added cover image and Table of Contents for "The Slide Rule - An Audio Tutorial Program", by Hoffman amd Ellis, Bell & Howell, 1973, 241 pp.
- Added cover image for "Streamlined Methods of Computing with Slide Rule and Mathematical Tables", by Mitchell, Craftsman Press, 1944, 32 pp.

3-25-16

- Added cover image and Table of Contents for "Calculation and Slide Rule", Thomas McHale, and Paul Witzke, Milwaukee Area Technical College, repr. By Addison Wesley, 1971, 618pp..

3-17-16

- Added a Reiss 3236 Darmstadt.

3-16-16

- Added a Ridgway's 1543 Darmstadt-type rule.

3-4-16

- Added cover image and Table of Contents for Breslich and Stone's "The Slide Rule", University of Chicago Press, 1929, 4th Impression,, 1942, 35 pp.

2-28-16

- Added a Nestler 37 Electro.

2-26-16

- Added a Bill-Mar No. 24 Concrete Calculator.

2-19-16

- Added a K&E N4100 Stadia Rule.

2-18-16

- Added a Perrygraf, PRD Electronics RF and Power Loss Calculator.
- From now on, for convenienvce of viewers, I will provide hyperlinks to newly added rules.

2-8-16

- Added a Graphoplex 692b Pocket Neperlog Duplex 5".

2-3-16

- Added a Union Instrument Co., No. 2050 Air Force Aerial Photo Rule Type A-1

1-28-16

- Added a Hemmi 130W Advanced Darmstadt

1-27-16

- Added a Nestler Total KG, Foerstner Radiation Protection Slide Rule.

1-26-16

- Wrote Python program to correct hundreds of spelling errors scattered across more than 500 html files. Haven't gotten to all the errors yet, but I'm working on it. If you see any such, please let me know. Massive apologies to those for whom English isn't a first language for (accidentally) leading them to believe that the word 'Materials" was spelled "Materals'. Sorry about that and other errors. In future, I will be much more careful in my use of file templates (and I'll use a spell checker).
- Added a Weber 42968 (same as Aristo 968).
- Added a K&E 68 1617 Mannheim Polyphase (a member in the 4053-series).
- Added a Uto 931U.

1-15-16

- Added a Pickett N540-T Pratt & Whitney Aircraft.
- Added a Blundell Luton Universal U.7.
- Added two more categories on the 'Specialty Rules' page (Spring Design and Weight of Materals).

1-14-16

- Added a (probably) VEB Mantissa of unknown purpose, probably something to do with solving specific types of triangular problems, angle of fire, surveying, etc.. If anyone can help me with this, I'd appreciate it.

1-12-16

- Added a Makeba Kombinator pencil slide rule.
- Added a Faber Castell 63/83 Castell Novo Biplex 5 (shorter version of 2/83).

1-9-16

- Added another version of a Hornyak & Kelley Weight Slide Rule
- Added a Datalizer; Ductile Iron Pipe Research Association's Pipe Network and Friction Loss Calculator.

1-8-16

- Added a Perrygraf; Concrete Pipe Association of Michigan, Inc., Hydraulic Slide Rule for the Design of Sewers.
- Added new pictures and some new data for the K&E 4012 Thacher, and the Stanley Fuller Model 2.

1-7-16

- Added an unknown (to me) Chinese(?) Brass Slide Rule. Have included expanded views of the Chinese(?) lettering on the scales. If anyone can help me identify this rule or explain to me what the scale lettering means, I'd really appreciate it!!
- Added a Perrygraf, Cast Iron Pipe Research Association's Pipe Network and Friction Loss Calculator.

12-30-15

- Added an Irving Goldfein Sewer Design Slide Rule (looks like a Perrygraf but isn't labeled as such).

12-19-15

- Added a Neal Feay CR-6 Cost Reduction Slide Rule.

12-17-15

- Added a Pickett 1025-T Associated Spring Corporation.
- Added a K&E 4081-3 Decitrig, Scale Set #5.

12-10-15

- Added a Pickett X-4 Executive.

12-9-15

- Added a Diwa 351 Darmstadt.
- Added a K&E N4096 Desk Slide Rule.

12-3-15

- Added an Aristo 914 Elektro.

11-30-15

- Added a Perrygraf Boonton Electronics Resonance Slide Rule.
- Added a Perrygraf Mallory Slide Rule for Capacitor Functions.
- Added an aluminum Reiss Darmstadt.
- Edited listing for a Reiss 3223 Progress.
- Added a Meissner KG Darmstadt.
- Added a K&E 4080-3 Log Log Duplex Trig, ser # 040646, with scale set #2.
- Added a K&E 68 1210 Log Log Duplex Decitrig, Ser # 380599, with scale set #6.
- Added a Cox & Stevens E-1113 Load Adjuster for the Sikorsky Seahorse helicopter.
- Changed listing for Revere Load Adjuster E-1147 for the C-130, to Cox & Stevens for the sake of consistency. Cox & Stevens was a division of Revere Corp. of America.

11-24-15

- Added Cover and Dust Jacket images and Table of Contents for Frank Rappolt's "Simplified Mathematics for Daily Use and How to Use a Slide Rule", Doubleday, 1943, 300 pp. The section on 'How to Use a Slide Rule' constitutes about 58 pages. 11-21-15

- Added an Aristo 966 Log Log.
- Added another version of an AcuMath 150.

11-19-15

- Added an Aristo 967U Darmstadt.
- Added an additional example of an Aristo 966H Log Log; this one with metal end braces.

11-18-15

- Added a Nestler 0218 Darmstadt.
- Added a Perrygraf ARRL L/C/F and Coil Windiing Calculator.

11-9-15

- Added a Faber Castell 111/98 Elektro.

11-3-15

- Added a Nestler 0129 5" Polymath Duplex.

10-29-15

- Added a Faber Castell 111/54 Darmstadt.

10-28-15

- Added a Nobema "Durer" 5914 Elektro.

10-26-15

- Added an IWA 0658 slide rule/chart for control valve calculations.

10-24-15

- Added a Hemmi 254WN "High School Student's".
- Added a Hemmi P262 Advanced Engineering (Rietz).
- Added a Hemmi P265 Business Duplex.

10-22-15

- Added a Hemmi 264.

10-21-15

- Added a Charvoz-Roos SR-108 Dual 10"/5" rule; essentially the same as the Post 1442 and Arthur Brown 7995A rules, but with metal end braces.
- Added another example of an Aristo 0970 Charvoz Multilog.

10-15-15

- Added an AcuMath 130 Log Log Decimal Trig (Magnesium) rule.
- Added a Hornyak and Kelly Weight Slide Rule.

10-13-15

- Added a Royal 1081 (Log Log Duplex) rule.
- Added cover image and Table of Contents for J. B. Arnold's "Slide Rule Problems and Solutions", Balt Publishers, 1962, 77 pp.

10-11-15

- Added a Perrygraf ARMCO Sewer Pipe Calculator.

10-9-15

- Added an AcuMath 150 Log Log Decimal Trig.

10-5-15

- Added a Pickett Model 1080-T (35350 Pocket Calculator for Orifice Meters, for The Refinery Supply Company)

9-30-15

- Added a Novotni Weight Slide Rule.

9-28-15

- Added a Ross Engineering Pipe Size Selector for Steam and Water.
- Added a UGK (Bulgarian) Slide Rule for Reinforced Concrete Calculations.

9-26-15

- Added a Perrygaf Cast Iron Pipe Research Association Loss of Head Slide Rule.

9-21-15

- Added an American Gas Journal Low Pressure Gas Flow Computer
- Added an American Gas Journal High Pressure Gas Flow Computer

9-18-15

- Added a Hutchison Pipeline Flow Calculator, for Gas, Air, Oil, and Water
- Added an ITAB Capacitor Calculator.
- Added three Perrygraf slide charts: an Allied Parallel Resistance and Series Capacitance Calculator, an Ohmite Parallel Resistance and Ohm's Law Calculator, and a Shure Reactance Slide Rule.
- Added another variant of the Logarex 27205 5" Exponent.

9-10-15

- Added an Aristo 10132 Reinforced Concrete Calculations (Baustahlgewebe-Lagermatten).

9-9-15

- Added an American Oil Company Discounted Cash Flow Slide Rule

9-4-15

- Added a Diwa 914 Log Log rule.
- Added cover image and Table of Contents for Mittelstadt's "Basic Slide Rule Operation, A Program for Self-Instruction", 2nd Edition, 1971.

9-2-15

- Replaced a Russian LFAI Open Duplex Log Log (LFAI 5161-57, r. 1970) with damaged cursor, with a Leningrad Open Duplex Log Log (5161-72, r. 1977), in C4 condition.
- Added a BRL P1415 Water Flow Calculator (Hazen-Williams Formula) for Stanton & Staveley Limited

8-25-15

- Added a Warren-Knight Novotni Weight Rule No. 1373-B.

8-23-15

- Added a Pickett 550-ES Warren-Knight Weight Rule No. 1373-C.

8-22-15

- Added a Perrygraf Boonton Electronics Slide Rule (Chart) for Reactance, Q, and Dissipation Factor

8-6-15

- Added a Pickett 535-ES Electronics Technician

8-3-15

- Added a K&E National Union Radio Slide Rule; used to find inductive or capacitative reactance at a given frequency, and resonant frequencies given values of inductance and capacitance.
- Added cover image and Table of Contents for "The Slide Rule Simplified, A Nonmathematical Text", by Thomas H. Blandi, Book Division of The Slide Rule Training Institute, Los Angeles, 3rd Edition, revised, 1943, 138 pp.

7-25-15

- Added cover image and Table of Contents for "The Use of the Slide Rule", by Allan R. Cullimore, Keuffel & Esser Co., New York, 2nd Edition, 1920, 38 pp.
- Added images of better example of the Staedtler Mars 944-28.

7-23-15

- Corrected my misstatement in the description of the Alvin 1151 that it was was a rebrand of the Relay/Ricoh 151. It is not.

7-8-15

- Added an Omega 151 (rebranded Relay/Ricoh 151).

7-1-15

- Added images of newer and cleaner example of the Nestler 0292.

6-30-15

- Added a Pickett N906-T National Fire Sprinkler Corp. Hydraulic Rule.

6-18-15

- Added a Post 1461 Versalog II 5".

6-15-15

- Added a Favor-Ruhl A-450 (like the A-400 but plastic stators and slide, not laminated.

6-14-15

- Added a Black, Sivalls & Bryson Control Valve Size Calculator slide chart by Perrygraf.
- Added an Aristo 870 Charvoz Multilog 5".

6-7-15

- Added images of newer and cleaner example of the Simplon Bilateral Log Log.

6-4-15

- Added a Dietzgen 1779 Pocket Log 5".

6-1-15

- Added images of newer and cleaner example of the Compass 1321 (Relay/Ricoh 150).

5-26-15

- Added a Marcantoni 25 CH Chemistry slide rule.
- Added a BRL Meterological Office Mk. IV Humidity Slide Rule

5-20-15

- Added a Tacro 4595 Log Log Duplex... similar to the Micador 530 and the Kent 9680.

5-18-15

- Added Pickett N4p-ES Vector Type Log Log Dual Base Speed Rule 5".

5-16-15

- Replaced cursor runners on K&E 4139 Cooke Radio Rule serial no. 979921 because of serious KERCS issues. Re-scanned repaired rule and replaced old images with new.
- Replaced missing cursor window on K&E 4093-3 serial no.548954, re-scanned repaired rule and replaced old images with new.
- Removed images and documentation for K&E 4090-3 serial no. 385485, which was basically acquired as a 'parts' rule anyway.
- Replaced broken cursor window and missing cursor screw on a Geotec 341 3012 Versalog II; re-scanned repaired rule and replaced old images with new.

5-9-15

- Added images of newer and cleaner example of the Weil Polylog (Diwa) 1140.

5-1-15

- Corrected mistakes in physical description of Teknor Gymnasium 1081
- Added cover image and Table of Contents for 'The Slide Rule and Technical Problem Solving', by Leach & Beakley, 1963, 3rd printing 1966.

4-26-15

- Added cover image and Table of Contents for 'Slide Rule Operations' by Dana Sudborough and Harold Zeoli, 1953, revised 1954, reprinted 1955.

4-25-15

- Added a Hemmi 258 also marked as Post Versalog 1460!

4-23-15

- Added an Aristo 971 Hyperbolog; same as the 0971 but with metal end braces.

4-15-15

- Added a Logarex 27729 rule, which is apparently used to make conversions between power and voltage, decibels and nepers, etc.

4-14-15

- Added a K&E 4181-1 with an SRT instead of an ST scale, and with red colored inverted and LL0 scales.

4-13-15

- Added a Bulgarian rule identified by the anglicized descriptor 'Vetoli"; a log log hyperbolic duplex rule.

4-11-15

- Added a Russian LFAI 'Metro Irrigation' hydraulic rule of some kind, apparently calculates flow characteristics in channels.

4-3-15

- Added second example of an Aristo 0968 Studio. This one with T1 and T2 scales instead of only a single T scale

4-1-15

- Added a Faber Castell 62/83N Castell Novo Duplex 5"

3-21-15

- Added a Dietzgen G-1734 Microglide Decimal Trig Log Log, probably made by Aristo.

3-27-15

- Added a Uto 0930U branded "Chemstrand"

3-24-15

- Added a Faber Castell 62/82N and a Grizzle Orifice Meter Calculating Rule (probably made by Lawrence Engineering?)

3-23-15

- Added a Nestler 33 Chemiker

3-20-15

- Added a Pickett N3p-ES 5 inch Power Log Exponential Log Log Dual Base

3-13-15

- Added a Hemmi 149A 5 inch rule; shorter version of the Hemmi 259.

3-11-15

- Added a Nestler 5 inch 0130 Multimath Duplex (same scale set as Nestler 0292, just shorter)

3-5-15

- Added an Engineer's 1510; same as a Relay/Ricoh 151 (but with what is probably a Versalog cursor, added by a prior owner!)

3-4-15

- Added a Pickett Model 1084 Resistance Design Slide Rule, apparently used by telephone company technicians in the 1950s.

2-23-15

- Added a Spring Design Slide Rule from Mid-Continent Spring Co., of St. Louis,MO. Prob. made by Acu-Rule.
- Abandoned my previous approach of putting a date on individual 'new' or 'updated' entries on the "All the Rules" and "Specialty Rules" pages in favor of just using this "What's New" page. Much less work for me and probably just as good for the viewer.

2-21-15

- Moved the Grizzle Water line Capacity Slide Rule from the "Unknown Manufacturer" category to "Grizzle". Still don't know the actual manufacturer, just trying to be consistent in the way I've listed various rules.
- Added Mear's Ducting Calculator for Heating, Ventilation, and Pneumatic Handling, etc.

Steve K. Seale, Nashville TN, USA, 2024