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Military/Government Issued Slide Rules


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These slide rules were used in Artillery and Ranging as well as Photography in scaling targets. Aviation and Flight computers, along with Load Adjuster Slide Rules used during WWII are located in the Aerospace Related Gallery as many continued to be used throughout the decades following the war for peaceful missions. The first record of U.S. Military Academy (USMA) using slide rules at West Point was in 1905. The first West Point class to be issued electronic calculators was in 1979. In 1929 the slide rule became a formal part of the U.S. Naval Academy (USNA) mathematics program and served as the midshipmen's primary calculator at Annapolis until 1976.
Some of these slide rule images are duplicated on their respective manufacturer or country pages.


WWII Submarine
Coning Tower (1943).

British RAF liaison officers at US 8th Air Force Bomber Command (1942)

Senior Sergeant Mikhail Kalashnikov (Kalasnyikov) the inventor of the automatic rifle named after him and designed in 1947

Instructor shows use of E6-B for Navigation Training at Kelley Field, TX (1942)

German Enigma Being Decoded 1940 The Secret War by Brian Johnson 1979

BBC TV Series The Great War - No25 Artillery Slide Rule

Air Traffic Controller The World At War Sep 1939-April 1944

Communications Post Fort Bragg, By Bernard Hoffman, Life

WWII British WAAF with Weather Pilot Ballon Predicting Weather. 1941 Getty Image

German Luftwaffe Crew Plotting Course Using Dreieckrechner
More military images may be found on the Historical Photos, People with SRs and Ephemera Gallery



Green Ship Length Computer

REF

Green Ship Length Computer
Made in USA by Alex. E.S. Green during WWII
Note: Designed by necessity and implemented during WWII for B-29 Crews.
For determining the size of Japanese ships, used in conjunction with the B-29 Gun sights. This slide rule was used to find the elusive Japanese battleship Yamato



Green Flight Engineers Computer

REF
Green Flight Engineers Computer
Made in USA by Alex. E.S. Green during WWII.
Note: Designed by necessity and implemented during WWII for B-29 Crews.
For maximizing the fuel range of B-29 Gun during long over-water missions. Created after the B-29 crew that found the Japanese fleet ran out of gas and had to land in Xian, China




Mo. Mattei Regolo Di Convergenza (Artllery)

ISRM 15.09.27.01
Nicola Marras - Italy. Collector, promotes through exibits and educational courses the memory of old calculating devices and ancient navigation systems. Nicola wants young people to understand that the world as we see now, skyscrapers, highways, atomic power, space exploration and the electronic computer, was possible because of simple tools like slide rules. His main event every year is the exibit at Cagliari festivalScienza. His goal is the construction of a permanent museum of calculus. Nicola Marras's Calcolatoria Website (both in Italian and English). Mo. Mattei Regolo Di Convergenza (Artllery)
Made in Italy by Mo. Mattei
Front Scale: 48cm// b [ d , β(1600-3199), β(1600-1) ϒ] b/D \\ 1:25000
Back Slide: [ Sen.ε, Cos.ε, tg.ε, L ]
Back: Instructions (Italian)
Gift of Nicola, Marras.



Nestler Aircraft Tracking (Fluggeschwindigkeit) 50cm/20in cWWII

REF

Photos of WWII Nazi Germany women tracking Allied bombing raids to provide advanced warning to German targets. They are using a Nestler Fluggeschwindigkeit slide rule for computations. The 20in (50cm) and 10in (25cm) models are shown here. Provided by Andreas Fassbender "The direction of flight of enemy formations was calculated in advance with the help of the signal box and the speed ruler. The speed ruler was in the form of a slide rule and enabled the rapid calculation of flight time, flight distance and flight speed in their dependence on each other. The reporting can was placed with its center on the location indicated in the report, and thus the presumed flight path was determined, taking into account the reported direction of flight. On the speed ruler, the time in which the endangered location could be reached was then calculated. In this way, the probable time of attack for prewarning and alarm could be determined. (42)" From the book Blitzmädchen ISBN 3-8289-0531-5.
Nestler Aircraft Tracking (Fluggeschwindigkeit) 50cm/20in cWWII
Made in Germany by Albert Nestler - Labels all in German.
Front Scale: 1:3000000 km // Entefernung km [ Flugzeit Min.Stunden, Flug-Geschw. ] Fluggeschwindigkeitkm pro Stunde \\ 1:1000000 km
Back : blank
Scan by Andreas Fassbender, Germany.




Nestler Aircraft Tracking (Fluggeschwindigkeit) 25cm/10in cWWII

ISRM 21.10.15.01
Nestler Aircraft Tracking (Fluggeschwindigkeit) 25cm/10in cWWII
Made in Germany by Albert Nestler - Labels all in German.
Front Scale: 1:3000000 km // Entefernung km [ Flugzeit Min.Stunden, Flug-Geschw. ] Fluggeschwindigkeitkm pro Stunde \\ 1:1000000 km
Back : blank





J.A. Nicholl & Co. APP OBS CF Fire Slide Rule MKVI 1917 (Artllery)

ISRM 15.06.25.01
Phillip Rodley is an avid Collector and contributor of slide rules to ISRM. Phil used a slide rule for one year at high school before calculators came in. He then spent 18 years working as a telephone linesman and later 18 years assembling and testing 11,000 volt circuit breakers. In all those years he never needed to use a slide rule, but recently has begun enjoying relearning slide rules and logarithms. J.A. Nicholl & Co. APP OBS CF Fire Slide Rule MKVI 1917 (Artllery)
Made in London, England by J.A. Nicholl & Co.
Aluminum construction
Front Scale: 3 decade (K) scale [ 3 decade (K) Minutes in apex angle, or Battery Range in Yards]
Back Scale: 3 decade (K) scale (yards) [ Sin ]
Back: Instructions (Italian)
Gift of Phillip Rodley, Upperhutt, New Zealand



K&E Short Base Triangulation Rule USArmy
ISRM 04.06.15.01


Initials: USBR
K&E Short Base Triangulation Rule US Army
Made in U.S.A. for the US Army - 20" long
Front Scale: Aux Angle "A", Mils [ Vertex Angle "t" mils, base "b" ] Range "R"
Back Scale: [ Vertex Angle "t" mils, base "b" ]
Cursor: 2 hairlines Meters/Yards


REF K&E M4 Graphical Firing Table Slide Rule - 1943
K&E M4 Graphical Firing Table - WWII
Made in U.S.A. by K&E for the US Army, 1943
18.25" long x 2.75" wide.x 0.62" Thick

Notes: The scales are obviously for artillery calculations. There are three slides for ranging the 75mm and 155mm Howitzer with various charges. There is a C and D scale which qualifies the rule as a slide rule. The rule is of the Mannheim type. The base of the rule is mahogany with a lighter wood used for the stators. The surface of the wood is painted and the scales are screened on.
Archive - Clark McCoy Collection


ISRM Howitzer 155mm Graphical Firing Table Slide Rules
Set of 5 - 1972/1974 Vietnam Era

Made in U.S.A. for the US Army, - 18" long x 3.5" wide x 0.25 Thick stock. These are more of a nomograph than a typical slide rule. The specimens were used by a Sgt. Woodard and exposure to the elements in Vietnam have caused the stock to expand and the cursor to shrink making them now unusable. The stress has caused a couple of the riveted plastic cursors to crack and break. A visitor, Paul, to ISRM explains that the hand-written black markings "B 1/230" on some of the rules stand for B(ravo) Battery (Btry), 1st Battalion (Bn), 230th Field Artillery (FA).

Howitzer 155mm Oct1972 GFT Charge 2 & 4


Howitzer 155mm Oct1972 GFT Charge 5 & 6


Howitzer 155mm Oct1972 GFT Charge 7 & 8


Howitzer 155mm Mar1974 GFT Projectile Illumination Charge 2 & 3


Howitzer 155mm Mar1974 GFT Projectile Illuminating Charge 5 & 7


Howitzer 155mm Oct1972 GFT HighAngle Charge 7P

FM 6-40 USMC Manual (27.3Mb) See Page 7-25 for info on GFTs

M114A1 155mm Artillery Crew Vietnam

Overview: To eliminate the difficulties in computing firing data that result from the need to interpolate, the graphical firing table was created. The GFT provides all the information needed to compute firing data in a slide rule form.

Parts: All GFTs are made in two parts.. The rule is a rectangular wooden base on which is printed one or more sets of scales. With a few exceptions, GFTs are printed on both sides. The second part of the GFT is the cursor. This is a transparent plastic square that slides on the rule. Engraved in the plastic of the cursor is a manufacturer's hairline used to determine values from the scales.
Types: The basic GFT format is the same for all weapons. These formats may be divided into three types: low-angle GFTs, high-angle GFTs, and shell illuminating GFTs.
Identification. All GFTs are labeled for identification. The first line of the label on low- and high-angle GFTs indicates the type weapon in bold type; that is, HOW 155mm. Immediately below the weapon type, in smaller print, is the identification of the TFT on which the GFT is based; for example, "155AM2." This is followed by the projectile type and nomenclature, such as "HEM107." The last line of identification of low-angle GFTs tells the charge for which the GFT may be used, such as "CHARGE 4." High-angle GFTs indicate the trajectory "HIGH ANGLE." Shell illuminating GFTs reverse the label with "PROJECTILE ILLUMINATING" on the top and the weapon type on the bottom.

To read more about a 155mm Field Artillery unit in Vietnam see The 1/92nd Field Artillery Association website.


155mm Ordanance




Geo. W. Richardson Ballistic Slide Rule Model of 1917
ISRM 04.11.09.01


Geo. W. Richardson Ballistic Slide Rule Model of 1917
Made in USA by Geo. W. Richardson for J. H. Weil & Co.
Front Scale: A (Yards or Meters) [ B (Mils) C ] D (Yards or Meters)
Back Scale: [ B (Mils) C ]
Note: This was not designed for a sliding cursor


Military Slide Rule, 14.5-inch No.18-6544-550-100
ISRM 22.07.06.56
Military Slide Rule, 14.5-inch No.18-6544-550-100
Made in USA under Government contract. No manufacturer's markings
Front Scale: Opposite Angle Deg, Mils [Apex Angle Mils, Deg, CI,C] D,A
Back Scale: [Tan, Sin-Tan, Tan ]
Back: Geometry formulae
Note: Same artwork as the 10-inch American Blueprint Military Slide Rule, This one has slots, with stops for a cursor, but the indicator is missing
The back is made of masonite.


Example of proper indicator (Cursor).


TM 6-240 Manual 3.35MB Pdf
Field Artillery Military Slide Rule




American Blueprint Military Slide Rule

ISRM 14.09.21.04
American Blueprint Military Slide Rule
Made in USA - by K&E for American Blueprint (Military contractor)
Front Scale: Opposite Angle Deg, Mils [Apex Angle Mils, Deg, CI,C] D,A
Back Scale: [Tan, Sin-Tan, Tan ]
Back: Geometry formulae
Gift Of Edward Wright, Texas.

TM 6-240 Manual 3.35MB Pdf
Field Artillery Military Slide Rule



American Blueprint Military Slide Rule

ISRM 22.07.06.50

American Blueprint Military Slide Rule
Made in USA - by K&E for American Blueprint (Military contractor)
Front Scale: Opposite Angle Deg, Mils [Apex Angle Mils, Deg, CI,C] D,A
Back Scale: [Tan, Sin-Tan, Tan ]
Back: Geometry formulae
Gift Of Cindy Tate, Bozeman, Montana.


D&P (Aristo) German Gr.W.34 Artillery Ranging (1943)

ISRM 18.09.17.21
D&P (Aristo) German Gr.W.34 Artillery Ranging Slide Rule (gwr Marz 1943, March, 1943)
Made in Germany by Dennert & Pape (Aristo)
Front Scales: W1 Erhohung(Elevation), E1 Entfernung(Range) [ G1, G2 Geländewinkel(angle of error in landing point ) ] W2 Erhohung(Elevation), E2 Entfernung(Range), S Flugzeit(time of flight)
Back Slide: [ G3 Geländewinkel a fur Flugzeit Aufsatzwinkel (angle at top of flight parabola) ]
MarksFace: gwr Marz 1943 - se. Gr. W. 34 - Nur fur den Dienstgebrauch!
Reverse: Instructions for use
Gift of Donald J. Bachelor Collection
Note: This specimen was used during WWII and was brought back to the U.S.A. by Colonel in Patten's Army in Stuttgart, Germany



D&P (Aristo) German GWR Artillery Ranging

ISRM 22.10.15.01
D&P (Aristo) German GWR Artillery Ranging Slide Rule
Made in Germany.. "GWR" reveals that this was manufactured by Dennert & Pape for the German Wehrmacht.
Front Scales: EM, Gerätekonst, Ablage in Winkelsekunden [ Ablage in m, Wehre e in hm ] Gerätekonstante
Reverse: (Instructions for use) Rechnungsbeispiele, 1.Messen nach Entfernung. 2.Messen nach Höhe.
Gift of Dave Zoumaras of San Diego, California. Belonged to father-in-law.

The above slide ruleis one used for correcting measurements made using rangefinders.


C01 USSR Artillery Ranging
USSR Soviet Artillery Ranging
Made in USSR
Front Scale: tg, tg, 10K [Sin1-00, Sin0-10, 10K] Tables

Archive Photo - No longer in collection


Fesenthal (Dalton) Dead Reckoning Computer (c1940-1944) Type E6B U.S. Army Version WWII

ISRM 14.07.02.12

Fesenthal (Dalton) Dead Reckoning Computer - Type E6B
Military Version made of Black Anodized Aluminum

Made in USA by G. Fesenthal & Sons, cWWII
Invented by Philip Dalton, LTJG (1903 - 1941) Patent: 2,097,116
Front Scale: Distance Naut Miles, True Air Speed (Time Min, Hrs, Density Altitude, Air Temp )
Back Scale: Wind Correction Angle( True Heading )
Original owner/user (written on sleeve): R.F. Cassidy, Lt. Col. U.S. Army (See bio below)
Gifted by the Ed Millis Collection, Dallas, Texas.
From Eyes of Artillery: The Origins of Modern U.S. Army Aviation in World War II (76MB PDF) by Edgar F. Raines, Jr.
R.F. Cassidy, Lt. Col (Later Major) is mentioned thropuight the text. [pg72] Robert F. Cassidy graduated from West Point in 1939 and was later a 1st Lt. in the 38th Field Artillery Battalion. Cassidy had washed out of primary flight training, but as battalion reconnaissance officer he often flew with the Army Air Forces observer squadrons. He knew every ripple of ground and every firing position at the Leon Springs Reservation. He had, moreover, a genuine flair for fire direction. In the comparative tests of observers before the arrival of the Army Air Forces squadron, Cassidy established the best record. Once airbornc in an L-4 he took an average of two minutes to bring fire on target. In contrast, Army Air Forces observers first had to locate the firing battalion, which sometimes proved difficult. They also did not always find the target. When they did, they required an average of twenty-five minutes to adjust fire on the first target and an additional seven minutes on another. The contrast in performance led the members of Flight B to make Cassidy an honorary member of the Class Before One. [g124] Cassidy headed the new air-observation post concept with the 2nd Division, and took the Field Artillery pilot course and graduated on 6 March 1944 with Pilot Class 17. [pg252] In the Southwest Pacific Area, June 1944-September 1945, General Douglas MacArthur did not place an artillery air officer on his staff, but during the last fifteen months of the war, he acquired two field army headquarters that exercised operational control over ground units. Each of these contained an artillery air officer - Maj. James McCord in Sixth Army and Lt. Col. Robert F. Cassidy in Eighth Army. [pg288] Cassidy as, a Major, later became the Tactics and Gunnery Division and then as a Lt. Col., the executive officer of the Division of Flight Training, a post he held until 6 May 1944, when he became the artillery air officer of U.S. Second Army with headquarters at Memphis, Tennessee. He co-authored athe manual on Technical and Tactical Training of the Field Artillery Sections 1983). Army Ground Forces Light Aviation, redesignated Army Aviation in 1949, owed its existence to the wartime exploits of thousands of air-observation-post pilots, mechanics, and observers. These men had an opportunity to contribute to the war effort because of the actions of ficld grade aviators such as R.F. Cassidy. Col. Cassidy (retired) was interviewed by the author during 1991.

Go to the Aviation Related Slide Rules Gallery to see all other military and commercial air navigation computers.



Japanese WWII Navy Bygrave Position Line Slide Rule For Navigation

REF
Japanese WWII Navy Bygrave Position Line Slide Rule For Navigation
Made in Japan - cWWII - Japanese copy of Bygraveslide rule
Bygrave scales. See Reference: "PositionLineSlideRules" By Ronald W.M. Riet.2008"
Archive - Ebay Photos
In 1920 Capt. Leonard Charles Bygrave of the Royal Air Force patented a slide rule design in which the scales formed helices wrapped around concentric telescoping tubes. This allowed the scales to be made sufficiently long (nearly 8 meters) to obtain the required calculational accuracy. Bygrave's method for solving the navigational triangle involves splitting it into two right triangles and applying Napier's rules. The required operations can then be reduced to a series of multiplications and divisions of the trigonometric functions of the relevant angles. By suitable rearrangement these can all be written in terms of cosines and cotangents, or equivalently secants and tangents, The Bygrave slide rule scales are the logarithms of these functions. Versions of the Bygrave slide rule were produced in Germany and Japan both for marine and aerial use. In German versions, a mechanism that allowed the sliding scale tubes to be locked to together during calculations was introduced. Reference: "Bygrave Scales" by Robin G. Stuart, 2014


Japanese Gunnery Correction Slide Rule

REF
Japanese Gunnery Correction Slide Rule
Made in Japan - 1936 pre WWII
Front Scale: tg, tg, 10K [Sin1-00, Sin0-10, 10K] Tables

Archive - Image from Duke University, Gessler Collection
A combination slide-rule/nomograph forcalculating ballistics corrections for temperature, barometric pressure, vertical and horizontal wind and muzzle velocities. Probably used in land-based Army operations in China. Weighing 16 pounds it measures 30x38x2.5 cm. It has a thick wooden base, thick bronze or copper dovetail slides (with matching serial numbers 26), and white brass faceplates. Three sliding scales are side-by-side, with a fourth sliding scale inserted in the center slide.


Hemmi "Sun" Type 98 Maneuvering Slide Rule c1938

ISRM 14.09.25.01


Japanese Battleship YAMATO

Another of these slide rules was discovered in a bunker, located under a mountain behind the old Taura pyrotechnic factory, which manufactered torpedos during WWII, and stored them within. The buildings are currently part of the Maritime Self-Defense Force Yokosuka Zosamu depot and Akebono Machinery Co., Ltd. The bunker with its network of tunnels is not open to the public. See Yakumo's blog (in Japanese). Google will do a decent translation.
Hemmi "Sun" Type 98 Maneuvering Slide Rule
Made in Japan by "SUN"
Background: "Type 98" denotes that it was created in AD1938 (Koki or Jimmu Era 2598), which is 1938 in western calendars. The type 98 Movement rule, is a polar coordinate measuring system and was designed to calculate tracking and range data between two moving ships (or objects) to, possibly, provide input to the Type 98 Hoiban and Shagekiban Low Angle Fire Control computer which was specially designed for the Yamato class of battleships (the Yamato and Murushi). It could also have been used as the primary calculator for the smaller guns that were not connected the the electromechanical computers on the main battery of guns. This slide rule could also have been used for Ship-to-Shore or Shore-to-Ship bombardement as well. Another feature of this slide rule is that the Maneuvering Board, with its rotating dial on the slide, can be used to determine course corrections and wind drift. Handy if the battleship Yamato or an aircraft carrier, is to launch an aircraft, it will calculate the best heading into the wind. Submarines, would also use a similar device to calculate intercept vectors. The design of this slide rule mimics the maneuvering board/tables of the Allies, designed in 1920, and is still in use today. The center of the dial is 'My' or 'Own' ship.
Scales and markings translated by Jiro Higuchi
Front Scale
Relative Coarse Angle // Speed of My Ship [ Speed of Standard Ship, Distance (Logarithmic Scale) nautical mile/Meters, ] Velocity \\ Velocity Ratio
Back Slide: Time Board, Distance by reading Hour/Nautical Mile or Minutes/Meters
Well: Velocity Ratio =>1, Angle of course alteration, Velocity Ratio =<1
Case: Naugahyde with military division "Air Armament 9/90"
Gift of Phillip Rodley, Upper Hutt, New Zealand
Phillip Rodley


V2 Rocket Ballistic Ranging Slide Rule

Reference Image from Pennemünde Museum


Replica of V2 Rocket Ballistic Ranging Slide Rule
ISRM 13.00.00.81

Note from ISRM curator, Mike Konshak, who is certified to build and fly high powered rockets: On the V-2 Rocket slide rule, all the scales are a variation of High vertical climb (maximum altitude), maximum range, burn closing speed. The V2 ballistic missile would shut off its motor at some point in its flight (burn closing speed) which was the maximum velocity at that point, which was determined by it s inertial guidance system. This would vary based on the desired range. At that point it went from the boost phase to the coast phase and begin slowing down due to parasitic drag and fell (still very fast) to its intended target. It was was not very accurate as it only went in the compass direction it was told to go. Full cutoff determined the range. This slide rule was not very different from other artillery calculators. The replica was made by the Curator from the image.

V2 Rocket Ballistic Ranging Slide Rule - c1942
Made in Germany - Heeresversuchsanstalt Peenemünde (Army Research Center Peenemünde)
Scales: Interpretation provided by Dr. Klaus Schug, as follows:
From distance from Pennemünde to London is about 950 KM or almost 600 miles. This would be the Maximale Reichweite = 950 KM. Its maximum vertical height was between 50 to 60 miles (80 to 95 KM) for long-range targets. This would be the senkrechte Steighöhe = say 90 KM.
I. zur senkr Steighohe - Vertical height in meters. Using 9.0 or 90,000 meters = 90 KM as the heigth for reaching London from Peenemünde to London
II. zur Maximale Reichweite - Using 90 KM (9x10*4) on scale I , then scale II would read about 7000 kg/m*2 = Ballistische belastung = 5163.2 lb.ft of load or stress on the rocket
III. senkrechte Steighohe - Looks like this scale was only for very short distances up to 80 KM using the top of scale IV as the distance desired and then looking at III to see how high up the rocket had to go to reach the distances on the top of scale IV.
IV. Maximale Reichweite - using this scale with III gave the maximum distance for the height in scale III.
V. zur max. Reichw. - Using the bottom of the scale, scale V, to hit longer distances, say 950 KM to hit London, yields on scale V.
VI. Brennschlussgeschwindigkeit - Yields a end of burn velocity 900 m/sec to reach London or a target at 950 KM.

V2 Rocket at Pennemünde

Archive - Image from Pennemünde Museum

Graphical Firing Table M24 No.7674035 Rule No2, Shell HE, M48


Graphical Firing Table M24 No.7674037 Rule No3, Shell HE, M48

Graphical Firing Tables for M24 75mm Howitzer
ISRM 18.04.06.62
Graphical Firing Table Slide Rule M24
75mm Howitzer Shell HE, M48

Made in USA - 1944-1953 U.S.Army for the M24 Chaffe Tank
Scales: Range, Elevation, Drift, etc
Gift of the Leroy Hausler Collection

M24 Chaffee moves on the outskirts of Salzburg, May 1945


Correction Tables insert 7674039


Graphical Firing Table M24 No.7674033 Rule No. 1

Graphical Firing Tables for M24 75mm Howitzer Shell HE, M41A1
ISRM 22.07.06.06
Graphical Firing Table Slide Rule M24
75mm Howitzer Shell HE, M41A1

Made in USA - post WWII, 1944-1953 U.S.Army for the M24 Chaffe Tank
Scales: Range, Elevation, Drift, etc
Gift of Cindy Tate. Victor B. Tate Collection

Correction Tables insert 7674039


U.S. Military 76mm Howitzer Artillery Set

ISRM 03.00.00.55
U.S. Military 76mm Howitzer Artillery 2 SR set
Made in USA - 1952 (Korean Era)
Scales: Range, Elevation, Drift, etc


Soviet-LFAI Artillery

REF S552
Soviet-LFAI Artillery
Made in USSR
Front Scale:
1:50000M, 1:25000M // β, N² [Sin, S&T, Tg, N ] NQ+1, L
Back Scale: [ Sin, S&T, Tg, N ]
Back: Position and spotter formulae
Multiple hairlined Cursor


LFAI Soviet Military Dual Circular

ISRM
Soviet Military Dual Circular - 1957
Made in USSR by LFAI, Leningrad
Left Scale: 10000 meter (Sin)
Right Scale: 10000 meter (Tg)
Back: Position and spotter formulae
Actual application unknown at this time


Royal Ordnance 81mm Mortor Ranging Slide Rule

ISRM 18.09.17.55
Royal Ordinance 81mm Mortor M252 M821 M889 HE Ranging Slide Rule - ©1986
Royal Ordnance Ammunition LTD. Series 1. 1989
19200 9354443/4, 1220-01-215-9410
Made in UK by Blundel Harling (BHL)
Range 10000 meter (Elevation)
Gift of Donald Bachelor Collection
The Watervliet Arsenal M252 81mm mortar is a crew-served, medium weight mortar which is highly accurate and provides for a greater range of 5,935 meters [3.68 miles] and lethality than the previous 81mm mortar. The M252 system consists of the M253 Cannon (tube), M177 Mortar Mount, M3A1 Baseplate, and M64A1 Sight Unit.


Vickers MK I (Aust) W.H.H..303 M.G. Slide Rule

ISRM 21.08.21.01
Vickers MK I (Aust) W.H.H..303 Machine Gun Slide Rule
Made in UK. Made of cast aluminum with duralium S.S. For MK VII Ammunition.
Front Scale: V.I. Metres To Yards [H.I.] Angle in Degrees | Range on Sights, Range Correction [ Range to Troops, Angle Required in Degrees ] Range for Wind in Yards, Line Correction.
, CI, C ] D, L
Back Scale Inch= 1 mile // Wind: [Wind 20 MPH: Head in mins, Range] Tables, Length of Cord forGraticule Purposes = 24 in [ True Base ] \\ Scale Yards
Note: Space on back for writing using a grease pen.
Acquired from Billy O'Toole,. Australia
Royal Australian Regiment of the 3rd Battalion operate a Vickers gun during fighting near Chipyong-ni during the Korean War, February 1951


Vickers MK III W.H.H. 1940 .303 M.G. Slide Rule

ISRM 21.08.05.01
Vickers MK III W.H.H. 1940 .303 Machine Gun Slide Rule,
Made in UK Made of solid wood. For MK VII Ammn.)
Front Scale: V.I. Metres To Yards [H.I.] Angle in Degrees | Range on Sights, Range Correction [ Range to Troops, Angle Required in Degrees ] Range for Wind in Yards, Line Correction.
, CI, C ] D, L
Back Scale Inch= 1 mile // Wind: [Wind 20 MPH: Head in mins, Range] Tables, Length of Cord forGraticule Purposes = 24 in [ True Base ] \\ Scale Yards
Gift of Phillip Rodley of Upperhutt, New Zealand.

1st photo:The British Army in France 1940: Troops from 2nd Battalion Middlesex Regiment, 3rd Division, training on the Vickers machine gun at Gondecourt, 21 March 1940. Imperial War Museums 2nd Photo:Vickers Machine Gun Slide Rule on hip of British Seargent in its carrying case (3rd Photo - Australian War Memorial).


Lawrence 505_U.S. Navy

REF S495
Lawrence 505_U.S. Navy
Made in USA - Peru, Ind. (Lawrence)
Painted wood body
Front Scale: A [ B, CI, C ] D, K
Back Slider
[ S, L, T ] Back: Conversion Chart


REF Lawrence - DeYOE Slide Rule, U.S. Army for Artllery Ranging
Lawrence - DeYOE Slide Rule, U.S. Army for Artllery Ranging
Made in USA by Lawrence
Front Scale: E-Mils [ R or H, R or dH ] UOE
Back: Not Shown
Archive - Scan donated by David Rance collection. Sassenheim, The Netherlands


Pickett Model 14 US Military Artillery Ranging (1959)

ISRM 18.04.06.83
Pickett Model 14 US Military Artillery Ranging (1959)
Made in USA - Round Black Logo, Stamped curved braces, Grooved flat lens.
Front Scale: LL1+/-, LL2+/-, A [ B, T Cot, ST, S Cos, K,  C ] D, LL3+/-, LL4+/-
Back Scale: Opposite angle Deg, Deg,  Mils, Mils [ Apex angle, Tan CoTan, Sin-Tan, Sin CoSin, Base C ], Distance D, A
Gift Of Leroy Hausler Collection


Pickett Model 14 US Military Artillery Ranging (1962)

ISRM 12.04.22.01
Pickett Model 14 US Military Artillery Ranging (1962)
Made in USA
Front Scale: LL1+/-, LL2+/-, A [ B, T Cot, ST, S Cos, K,  C ] D, LL3+/-, LL4+/-
Back Scale: Opposite angle Deg, Deg,  Mils, Mils [ Apex angle, Tan CoTan, Sin-Tan, Sin CoSin, Base C ], Distance D, A


US Navy Calculator For Vertical Aerial Photography, MIL-C-19729

ISRM 15.03.18.01
US Navy Calculator For Vertical Aerial Photography, MIL-C-19729
Made in USA by Fesenthal Instrument Co., Mfg Part Number FNA-82B U.S.
Front Scale: Air Speed, %Overlap (Minutes, Hours, Density Altitude, Air Temp., Pressure Altitude
Back Scale: Feet On Ground, Scale,Focal Length, Exposure, Ground Speed, etc(Feet on Negative, Altitude)
Gift of Aron J. Davidson
Aron writes: "I was an engineer for the Navy (Civil Service)for almost twenty years, and then another twenty five or so as a contractor. I spent a big chunk of my time working on R&D of tactical airborne photographic reconnaissance systems. There really isn't much of a story to go with this slide rule. It was primarily for operational use in mission planning, which I rarely got involved in, but someplace along the line it wound up in my desk drawer; and I'm a bit of a packrat." Aron gave his granddaughter a Pickett slide Rule that he used.


Union Instruments MIL-C-4318-B Type A-1

ISRM
Union Instruments MIL-C-4318-B Type A-1
Made in USA by Pickett
Front Scale: L, A, DF [ CF, CIF, T, S, C ] D, DI, K
Back Scale: Ground Size Meters, Feet, Ground Speed, [Image size, Cycling Time, Focal Length ] Altitude
USAF Manual 8.69Mb


P232 Pickett N700-T USAF Aerial Photo Type A-2
Pickett N700-T USAF Aerial Photo Type A-2
Made in USA for the USAF
Front Scale: L, A DF [ CF, CI, T, S, C ] D, DI, K
Back Scale: Ground Size Meters, Feet, Ground Speed, [Image size, Cycling Time, Focal Length] Altitude
USAF Manual 8.69Mb


Pickett N520-T USAF Aerial Photo
MIL-C-4318-B Type A-1

ISRM 14.11.04.01

Pickett N520-T USAF Aerial Photo - MIL-C-4318-B Type A-1
Made in USA by Pickett. Aluminum stock.
Front Scale: L, A, DF [ CF, CIF, T, S, C ] D, DI, K
Back Scale: Ground Size Meters, Feet, Ground Speed, [Image size, Cycling Time, Focal Length ] Altitude
Original owner used this in Rotorau, New Zealand, assumed to be part of the Royal New Zealand Air Force.
Gift of Phillip Rodley, Upper Hutt, New Zealand.
USAF Manual 8.69Mb


USAF Type A-1 Aerial Photo

ISRM 04.09.30.01
USAF Type A-1 Aerial Photo - c1950
Made in USA for Astrodyne by Precision Scale Co. (founded by Art Eckel)
Front Scale: L, A, DF [ CF, CIF, T, S, C ] D, DI, K
Back Scale: Ground Size, Ground Speed, [Image size, Cycling Time, Focal Length ] Altitude
USAF Manual 8.69Mb


Air Navigation Attack Computer Type CPU-73A/P

REF
Air Navigation Attack Computer Type CPU-73A/P (9 inch Diameter)
Made in USA by Allegheny Plastics, Inc (APAF 53). Other maker: Felsenthal Instruments.
Note: Government contract No. F34601-80-C-1560, NSN 6605-00-435-1481 MIL-C-83856 (USAF)
Front Scale: Turn Radiuis 45° Bank, Turn Radius 30° Bank (Target TAS, Interceptor TAS Minutes-Seconds, Lead Distance, LOP Angle, Temperature, Air Speed Table.)
Back Scale: Compass Rose, Wind Correction, Calibrated Air Speed Table.
Archive - Not in collection


Crichlow Circular (Artillery) Slide Rule (1936)

ISRM 04.09.27.02.D1 (In Display)
Crichlow Circular (Artillery) Slide Rule
Designed by Robert Crichlow (1936). 12in (25cm) Dia Cardboard disc - One-sided
Front Scale: A(1/sinA), B(1/cosA), C(Tan Cot), D(1/sin), E, F(Squares)
Solutions of Triangles
Per Brian Bourchers: This design was developed for the US Army coastal artillery in the pre WWII period.. Notice that the outer scale goes to 6400 as there are 6400 mils in a circle under the military system.In artillery work, all angles were given in the mil system, with 6400 mils to a full circle, 1600 mills to a right angle, and so on. The outermost scale was a simple scale of 6400 mils, allowing the slide rule to be used as a circular protractor. The remaining scales moving from the outside to the center were simply labeled A through F. See The Crichlow Circular Slide Rule by Brian Bourchers



REF Radiac Nuclear Yield Calculator Set ABC-M28A1 - Disk One


REF Radiac Nuclear Yield Calculator Set ABC-M28A1 - Disk Two
Radiac Nuclear Yield Calculator Set ABC-M28A1
Made in USA - NATO number NSN6665-00-130-3616, 4-1/2in Dia. plastic
Scales:
TIME OF ENTRY, ENTRY-EXIT TIME AFTER BURST, DOSE-RATE (RADS/HOUR), DOSE (RADS), TRANSMISSION FACTORS, YIELD-STABILIZED CLOUD BOTTOM (KT), STABILIZED CLOUD BOTTOM OR TOP OF ELEVATION ANGLE, ALIGN FLASH-TO-BANG TIME WITH ELEVATION ANGLE, READ YIELD ON APPROPRIATE SCALE UNDER POINTER, DISTANCE TO GROUND ZERO (KM), FLASH-TO-BANG TIME (SECONDS), YIELD FROM ILLUMINATION TIME, FIREBALL ILLUMINATION TIME (SECONDS).

Carrying sleeve, sample problem card
Archive - BajaRon photos placed on ebay


Rand R-1380-PR Damage Probability Computer

ISRM 21.08.07.02

Rand R-1380-PR Damage Probability Computer (1974)
Made in USA for the U.S. Air Force.
Front Scales: Yield, Weapon Radius, Single shot Damage Probability, K-Factor Adjustment
Back Scales: Yield, Weapon Radius, Single shot Damage Probability, K-Factor Adjustment
Gift of William Lisowski



BRL Radiac No1 Radiation Exposure

ISRM 21.08.07.01

BRL Radiac No1 Radiation Exposure (1951)
Designed by William Orr (1951), BRL Mod/NSN Nr.:6665-99-911-0060 made for British & Canadian Governments.
Note: There is a second PINK disk missing. See it HERE (David Rance Collection).
Front Scales: Dose, Exposure
Back Scales: Yield, Weapon Radius, Single shot Damage Probability, K-Factor Adjustment
Gift of William Lisowski


The Slide Rule at West Point by Fred Rickey (1998)

1905

"For the purpose of acquainting the cadets with the various mechanical devices used as aids in performing calculations they have received instruction in the use of the slide rule and of several calculating machines. The required use of the slide rule in the solution of the problems in connection with the daily lessons had given to a large part of the class a satisfactory facility in the use of this instrument. An arithmometer, one of the best of the calculating machines, has been purchased for the use of the department [of Ordnance and Gunnery]. This machine, together with other machines of like nature in the possession of the other academic departments, has been a subject of instruction." [Superintendent's Report, 1905, p. 41]

1906

After Echols was sent to Europe in 1905-06 he wrote a Report of Visits to Foreign Schools and Recommendations Resulting. The original of this is in the USMA Archives. Here is one comment:

"It seems advisable that time be found in the course in mathematics to resume the instruction in the theory and use of the slide-rule which was once taught in conjunction with the course in surveying and is now taken up in the course of Ordnance and Gunnery. It could be best added to the course in trigonometry of the 4th Class year, its use to continue throughout the next three years."

You will find my notes on the report of Echols at

http://www.dean.usma.edu/math/people/rickey/dms/DeptHeads/Echols-Europe.htm .

I don't know if the surveying course mentioned above was taught in mathematics or not; I will do some more checking and try to figure it out. But the way Echols expresses himself it seems that the slide-rule was taught at WP in 1906; it addition it appears that it goes back a few years. The quotation in the previous section  shows that it was indeed taught in Ordnance and Gunnery in 1905.

1914

The Slide Rule: A Manual of Instruction prepared under the direction of Gilbert A[lbin] Youngberg (1875-1962, USMA 1900, C#3947, Instructor USMA 1910-1914) by Roger G[ordan] Alexander (1883-1961, USMA 1907, C#4532, Instructor PME USMA 1912-16; First Dean of the Academic Board), was published at West Point in 1914. One copy is in the USMA library:  Textbooks-SPEC: QA73. A4

1919

"Difficulty was experienced in securing slide rules for the use in the department [of Natural and Experimental Philosophy] although they were ordered as early as practicable. These are now part of the regular equipment for the cadet in the department of philosophy and their appropriate use is obligatory in this department. [Superintendent's Report, 1919, p. 25]

1929

In 1929 the slide rule became a formal part of the mathematics program and served as the midshipmen's primary calculator until 1976. [From:"A Brief History of the Department of Mathematics" by Professor T. J. Benac] https://www.usna.edu/MathDept/_files/documents/mathdept_history.pdf]  http://www.pballew.net/mathbooks.html

1930

Notes on the Slide Rule: Notes on Precision of Measurements, Computations, and Graphical Methods. 1930. Copy in USMA Special Collections:  QA73 .N68 1930.  There were also editions of this in 1933 and 1935. [Mentioned in 1933 below.]

1933

"56. The course in natural and experimental philosophy extends throughout the second-class year. The  slide rule, precision of measurements, computations, and graphical methods, general astronomy, surveying, and a portion of technical mechanics (statics) are taught in the order mentioned during the second term." Then more details on each of these first term courses follows: "The Slide rule - Three periods only, based on Notes on the Slide Rule [see 1930 above] prepared in the department. This shout course is intended as a refresher course following theoretical instruction given in another department [which department ??] during the third class year. Following these three days' [sic] instruction on the practical use of the slide rule and after about two weeks' [sic] use in the section room, appropriate use of the slide rule for computations in the department is obligatory." [Information for Appointment, 1933, p. 19]

1934

In the Information Relative to the Appointment and Admission of Cadets for 1934 under the Department of Natural and Experimental Philosophy one finds "The slide rule . At the beginning of Academic work on September 1 and for about two weeks thereafter, a portion of each period of instruction is devoted to the use of the slide rule, and thereafter proper use of the slide rule for computations in the department is obligatory."

1943

The 1943 Superintendents Report, p. 3, indicates that "Instruction in the slide-rule will be taken over from the Department of Physics."

1945

The slide rule is not mentioned in the 1945 Information Pamphlet.

1946

The 1946 Catalog, p. 44 (image 52), indicates that the slide rule is taught in the Mathematics Department for 9 periods of 80 minutes duration, i.e., for 12 hours. No detail is given about what is taught.

1947

Class of 1947 at MIT used slide rules.

http://brownalumnimagazine.com/printerfriendly.cfm?ID=1166

1961

In a memo headed "Report of Activities, Training Aids Committee" dated 19 June 1961 there is a note of contact with K & E "regarding plastic slide rule for use with the vu-graph." There is a handwritten note that these should be in use by late fall. According to another memo (9 February 1961) Mr. Thomas "arrived with a pilot model of a plastic slide rule for demonstration and comment" on 25 January 1961. Seven suggestions are made for improving the device. There is a list of training aids. It includes 23 string models and one Mechanical Integrator and 36 Spherical Blackboards, 27 "Slide Rule and Stands (8ft)" for use in Fourth Class slide rule instruction. [Mathematics Department Diary, 1960-1961, tab 13]. One plastic slide rule for use with the overhead survives (but is it the same one mentioned above?); apparently these had a tendency to soften and twist if left on the overhead too long and were then unusable.

The 1961 Howitzer, the cadet yearbook, has a photo of a cadet who has been stabbed in the back by his slide rule.

1979

This was the first class to be issued calculators.

References:

'Catalog' is the short title used here for United States Military Academy, West Point, NY, Catalog of Information.  This began publication in 1946 and supersedes the Information for Appointment.

'Information for Appointment'  is the short title used here for Information Relative to the Appointment and Admission of Cadets to the United States Military Academy, West Point, NY.  This was published annually by the Government Printing Office. The year is specified in the citations above. This was published until 1944. In 1945 the title was Information Pamphlet. Then it is succeeded by the Catalog.


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International Slide Rule Museum