A Collection of Slide Rules

SLIDE RULES

First, a little background:
About 1614 John Napier discovered the logarithm - a characteristic of a number which allowed addition and subtraction to be used in place of the more cumbersome multiplication and division to solve mathematical problems. He didn't invent the logarithm- it was always there, but nobody knew it. Napier found that by adding the numerical values of two logs (as they are called) the resultant value was indeed the log of the product of the original two numbers whose logs had been added up in the first place. Edmund Gunter carried it a little further by making a ruler on which the position of the numbers was proportional to their logarithms. He used a set of dividers to add two lengths together, the resultant length being the product of the original two numbers. A few years later, William Oughtred put two of the rulers together and slid them back and forth to accomplish the same thing, and voila, the slide rule. The rest, as they say, is history.

The slide rule in its many manifestations and incarnations ruled until about 1973, when electronic calculators became widely available and "cheap" ($100-200). Today, scientific electronic calculators are buyable for under ten dollars, while slide rules sometimes cost several hundred dollars. Go figure!!

THE COLLECTION

Meanings of commonly-seen scale designations:
A x^2
B x^2
C x
CI 1/x
CIF 1/(pi)x
D x
DI 1/x
DIF 1/(pi)x
K x^3
L mantissa of common log of D
LL03-LL3 log log scales
S on D, sine of angle S
T on D, tangent of angle T
ST sine and tangent for small angles
"Mannheim", "Darmstadt",and "Rietz" were names given to slide rules with certain arrangements of scales, so as to standardize them. The standards were honored as much in the breach as in the keeping.
Mannheim = the simplest: just A, [B, C], D.
Rietz = same as Mannheim, with S, T, ST and sometimes L, K, and CI added.
Darmstadt = with all the above, plus LogLog scales, and occasionally P.
"Open frame" means front and back of the slide are visible; "closed frame" means only the front is visible.
"Simplex" means only one side of the rule is used; "duplex" means both front and back sides are used.
"Linear" means the rule is straight as opposed to "circular".

ACU-Math #12, 5" scales
Yellow, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: K, A, [B, CI, C], D, L. The back of the rule is blank. Inexpensive, Mannheim-type rule with instruction booklet, all in plastic box.
ACU-Math #400, 10" scales
Linear, open-frame, simplex plastic rule. Scales are S, K, A, [B, CI, C], D, L, T. Cheaply made, common. No box, no case.
ACU-Math #400B Mannheim, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. All scales are on front of rule and slide. Scales: S, K, A, [B, CI, C], D, L, T. Rear of rule shows equivalents and settings, rear of slide has decimal/fraction equivalents. With a rather ratty scabbard. Made in USA.
ACU-Math #500, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: S, K, A, [B, CI, C], D, L, T. Back of rule has decimal equivalents and conversion tables. With leather scabbard. Made in USA.
ACU-Math #511 Mannheim Professional, 10" scales
White, wood-core, plastic-laminated (? possibly aluminum), linear, open-frame, simplex rule with plastic cursor. Scales: S, K, A, [B, CI, C], D, L, T. Back of rule has decimal equivalents, trigonometric relationships and formulae, metric equivalents, and settings. Cursor has knurling in top and bottom. Seems to be a heavy, well-made rule. With plastic scabbard. Made in USA.
ACU-Math #600, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: S, ST, K, A, [B, CI, C], D, L, T. Rear of rule has decimal/fraction equivalents, trigonometric relationships, and weights, measures, and physical equivalents and settings. With plastic scabbard.
ACU-Math #1200, 5" scales
White, plastic, linear, open-frame, simplex rule with plastic 2-hairline cursor. Scales: K, A, [B, CI, C], D, L. Rear of slide: S, T. Back of rule is blank. With leather scabbard. Made in USA.
ACU-Math #1240, 10cm scales
White, linear, plastic, open-frame, simplex rule with plastic cursor. Front scales: K, A, [B, CI, C], D, L. Nothing on the back. With leather scabbard.
ACU-Math #1300 LogLog Decimal Trig, 10" scales
White, plastic, linear, open-frame, duplex rule with plastic cursor. Front scales: LL01,K, A, [B, T, ST, S],D, L, LL1. Rear scales: LL02, LLO3, DF, [CF, CIF, CI, C], D, LL3, LL2. Rather well-made rule, with leather scabbard. Made in USA. Not listed in Hopp*.
ACU-Math #1311 Log Log Decimal Trig, 10" scales
White, plastic-laminated, wood, linear, open-frame, duplex rule with plastic cursor. Front scales: LL02, LL03, DF, [CF, CIF, CI, C], D, LL2, LL3. Rear scales: LL01, K, A, [B, T, ST, S], D, LL1. Rule is heavy, feels like metal. With a tattered, woe-be-gone leather scabbard. Made in USA. Not listed in Hopp*.
Aristo #89, 12.5cm scales
Small, linear, closed-frame, plastic rule with plastic cursor. Probably made by Dennert and Pape. Front scales are K, A, [B, CI, C], D, and L. Scales on back of slide are S, ST, and T. Has a hairline on back, also serial #G5320, and a 13cm scale. Housed in soft leather scabbard.
Aristo #0903 Scholar, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: K, A, [B, CI, C], D, S, T, L. Back of rule has resonance and reactance formulae, Ohm's law, power factor, Q, some equivalents. Ten-inch rule is at the top on scale side. Originally made in Germany for use of Cleveland Institute of Radio Electronics students. Cursor has 3 index marks. In cardboard slip-in box.
Aristo #10175 Electronic, 10"scales
White, plastic, linear, open-frame simplex rule with plastic cursor. Scales: LC, 2pi, A, [B, CI, C], D, S, T, L. Rear of rule has a variety of electronic formulae, metric, trigonometric, and unit equivalents. Cursor contains 4 hairlines. Back of rule says "Copyright 1958, Cleveland Institute of Electronics, Cleveland 3, Ohio". With slide-top box. Made in Germany.
Blundell-Harling #S150-10, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: S, T, A, [B, CI, C], D, K, L. Back of rule is blank. Made in England from 1975-82, designated as "School Education Slide Rule". With instruction booklet.
Charles Brunning Co. #2420, 10" scales
Linear closed-frame plastic. Top has beveled 10 " scale, bottom has beveled 25cm scale. Front scales A, [B, CI, C], D, and K. Back of slide are S, L, and T scales. Rear of rule shows weights, measures, settings, formulae. Housed in cardboard scabbard.
Charvoz-Roos #SR-109, 10" scales
White, plastic-laminated wood (mahogany?), linear, open-frame, simplex rule with plastic cursor. Scales: T, DF, [CF, CIF, CI, C], D, S, ST. Back of slide: B, K, L, C. Note there is no "A" scale, but 2 "C" scales. Back of rule has conversion equivalents, decimal equivalents of fractions, trigonometric values, relationships, and formulae. Made in USA.
Clifford Manufacturing Co. (no model no.), 6" scales Small white plastic linear closed-frame simplex device. Has 2 or three product selection tables on front, but also C and D scales, which qualify it as a slide rule. Back side has product advertising. Made by Whitehead-Hoag, NJ. I put it in the collection because of the name.
Concise #28N, 26cm outer scale
White, plastic, circular, simplex rule with clear plastic cursor. Scales: D, [C, CI, A, K]. Reverse side has equivalents, conversion factors, and formulae. With plastic slip-in case and instruction booklet. Made in Japan.
Concise #270, 10" outer scale
Duplex, 4" circular white plastic, 3mm thick, with clear plastic cursors on both sides. Front scales L, D, [C, CI, A, K]. Rear scales DI, D, [S, T1],T2, ST. Also labelled "Lafayette 99-7127". Lafayette was a merchandiser on the order of Radio Shack. This specimen in excellent shape, with plastic case and 36-page, 2 3/4" x 4" instruction booklet. Made in Japan, probably after 1955, when occupation ended.
Concise #1450, 25cm outer scale
White, plastic, circular, simplex rule with clear plastic cursor. Scales: D, [C, CL, A, K]. Reverse side has equivalents and conversions. With plastic slip-in case and instruction booklet. Made in Japan. Inscribed "Babcock & Wilcox". Given by Jim Walker, Barberton, OH.
C-Thru Ruler Co. #27, ca 5 3/4" scales
White, linear, closed-frame, simplex rule with plastic cursor. Scales: A, [B, CI, C], D. Reverse of slide (badly worn): S, L, T. Top and bottom of slide have inch and centimeter scales. This is a small plastic advertising giveaway rather than a serious calculating device. With instruction sheet and plastic sleeve imprinted "Elastic Stop Nut Corporation of America, Union, New Jersey". Back of rule shows decimal equivalents of fractions.
C-Thru Ruler Co. #S888, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. All scales are on the front of the rule and slide. Back sides are blank. Scales: S, K, A, [B, CI, C], D, L, T. Made in Japan. With instruction booklet and limber plastic sheath.
Dietzgen #1732 Maniphase Multiplex Deci-Trig Log Log, 10" scales
This linear,open-frame, duplex rule (nominal 10 in.) was purchased in Columbus, OH, about 1952 or -53, at University Bookstore, OSU. If memory serves, it cost about $20. The front scales are LL01, K, A, [CF, CIF, CI, C], D, L, LL1. Rear scales are LL02, LL03, DF, [B, T, ST, S], LL3, LL2. With manual, case, conversion table card. Ser. #564277
Dietzgen #1738 Multiphase Style-M Improved decimal Trig Type Log Log, 10" scales
White-enameled, aluminum, linear, open-frame, duplex rule with plastic ("fulvue") cursor. Front scales: LL01, K, A, [B, T<45, T>45, ST, S], D, DI, LL1. Rear scales: LL02, LL03, DF, [CF, CIF, L, CI, C], D, LL3, LL2. The name of the rule is a mouthful. Enameling is coming off the aluminum; rule is in "not-so-hot" condition. Made in Germany from 1955-1970. Has an excellent leather scabbard.
Dietzgen #1739-L, 10" scales
White, plastic, linear, open-frame, duplex rule.with plastic cursor. Front scales: L, K, A, [B, CI, C], D, LL1, LL2, LL3. Rear scales: T1, T2, DF, [CF, CI, C], D, S, ST. A-B, C-D, and CF-DF scales are color-coded green. Front of cursor has 4 hairlines- leftmost unmarked, center marked s, d, and kW, third (lower) marked d, rightmost marked HP- used for special calculations. With insruction booklet and scurvy-looking cardboard scabbard marked "made in Germany". Made until 1972.
Dietzgen #1745LM Maniphase, 10" scales
White, plastic-laminated wood, linear, open-frame, duplex rule with glass and metal cursor. Solid, high-quality construction and smooth slide and cursor action. Front scales: A, [B, CI, C], D, L. Rear scales: K, A, [S, T], D. Has a scuffed-up leather scabbard. Made in USA.
Dietzgen #1757 Primatrig, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: L, K, A, [B, CI, C], D, T, ST, S. Back of slide shows trigonometric relationships, decimal equivalents, quantity equivalents, and settings. With hard cardboard scabbard case. Made in USA.
Dietzgen #1759B (?), 10" scales
White, wood (mahogany or walnut?), linear, closed-frame, simplex rule with glass cursor, metal top and bottom. Scales: A, [B, R, C], D. Rear of slide: S, L, T. On the bottom of the body is an E scale, on a bevel on the top is a 10" ruler. Some cluck has attempted to repair a crack in the end of the body, and the slide is stuck. No case, no instructions, slide is immobile.
Dietzgen #1767 National, 10" scales
White, linear, open-frame, plastic, simplex rule with plastic cursor. Scales: K, S, A, [B, CI, C], D, T, L. Back of the rule is totally blank. Very readable, uncluttered design. With leather slip-in case, instruction booklet "MANIPHASE Slide Rule", and box. Made in USA. Several rules were made with #1767 but with different names (this one is "National").
Dietzgen #1767P National, 10" scales
White, wood, linear, closed-frame, simplex rule with plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. Back of rule shows weights and measures equivalents, decimal equivalents of fractions, 10" and 25cm rulers. With instruction booklet and cardboard sleeve.
Dietzgen #1768P Reliance, 10" scales
White, wood, linear, closed-frame, simplex rule, with plastic cursor. Scales: A, [B, CI, C], D, K. Back of slide : S, L, T. Rear of rule has 10", 25cm rulers, list of equivalents and decimal equivalents of fractions on badly worn and torn paper strip. With a leather-like slide-in case. Made in USA.
Dietzgen #1771 RediRule, 5" scales
White, linear, plastic, closed-frame, simplex rule, with plastic cursor. Scales: A, [B, CI, C], D, K. Back of slide: S, L, T. Front is bevelled top and bottom, with 5" ruler on bevel and 12.5cm on bottom bevel. Used as advertising give-away, says "ACF ELECTRONICS DIVISION" on back of rule. With a nice leather slip-in scabbard.
Diwa #601-1, 10 cm scales
A small (4 1/4") rule with International Rectifier logo on back, case, and slide-out box. Has inches/millimeters at top front, A, B, C, Cl, D, K, and L scales on front, and S, ST, and T scales on back of slide. Made in Denmark. In leather case and box.
Empire #240 "Pedigree", 10" scales
White, plastic, linear, closed-frame, simplex rule with plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. The slide rule is mounted on a plastic base, with a 12" ruler at the top and a 24cm ruler at the bottom. The back of the mounting base is blank white. With instruction pamphlet (2 copies). Made in USA. Two specimens, one in unopened bubble-pack, not mounted on base, with original price of $1.29.
Engineering Instruments, Inc. #10-B, 9 1/2" scales
White, wood, linear, closed-frame, simplex rule with metal-rimmed plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide has no scales. With cardboard box, no instructions. Made in USA. This specimen has a sticky slide.
Engineering Instruments, Inc. #10-BK, 9 1/2" scales
White, wood, linear, closed-frame, simplex rule with metal-rimmed plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide has no scales. With instructions, cardboard box. Made in USA. Same specs as #10-B.
Engineering Instruments, Inc. #250-V, 10" scales.
Made in Peru, Indiana. Linear closed-frame wood. Front scales are A, [B, CI, C], D. K. Back of the slide are S, L, T. Rear of rule shows equivalents, conversions, weights, instructions, et c. Plastic overlay broken, cosmetically poor. Another bad-looking rule.
Faber, A. W., #339, 25cm scales
White, celluloid-laminated, wood, linear, closed-frame, simplex rule with plastic cursor. Scales (unmarked): A, [B, C], D. on body beneath slide appears the model number, the balance scale logo, and A. W. Faber Schulrechenstab. Made in Germany. The celluloid lamination is secured with wooden pegs. Very smooth action. Not listed in Hopp*.
Faber-Castell #1/60 Standard Trig, 10" scales
White, wood, linear, closed-frame simplex rule. Scales: A, [B, CI, C], D. Rear of slide: S, L, T. Top-edge bevel has 10" ruler, bottom edge has 30cm ruler. Back of rule has conversions, equivalents, and formulae. Very well-made rule, has hard plastic flip-top case. Made in Germany. This specimen is missing a cursor (snookered again by the eBay hucksters!).
Faber-Castell #57/88 Student Advanced Rietz (probably), 10" scales
White, linear, plastic, closed-frame, true simplex rule with 1 15/16 wide plastic cursor. Scales: K, A, [B, L, CI, C], D, S, ST, T1, T2. No scales on back of slide. The rule is about 49mm wide. Some scales are color-coded. A 10" ruler is on the top bevel. Various equivalents are on the back, but worn down. With a transparent plastic case.
Festus Mfg. Co., (no model #), 10" scales
Linear, closed-frame, painted wood (boxwood?) simplex rule. Front scales A, [B, CI, C], D, and K. No scales on reverse of slide. Rear of rule has measurements, conversions, settings, et c. Says "Festus Mfg. Co., Festus, Mo." on back. Has the same physical appearance as K & E N4053-3. Cursor is missing.
Frederick Post #1441, 4" scales
White, linear, closed-frame, simplex, bamboo rule, with a metal-rimmed plastic magnifying cursor. Scales: A, [B, CI, C], D. Rear of slide: S, L, T. Slide moves on metal plate. A very small rule, not found in Hopp*. No case or instructions. Has the "Sun Hemmi" logo and "D 1" on the back.
Frederick Post #1444, 5" scales
White, wood (bamboo?), linear, closed-frame, simplex rule with a metal-edged glass cursor. Scales: A, [B, CI, C], D. Rear of slide has S, L, T. Sun Hemmi logo appears on front, as well as a 5" ruler on the bevelled top edge. Has a leather scabbard with a name and address on back. A nice little rule.
Frederick Post #1444K, 5" scales
Same as #1444 but with addition of K scale. Given by Jack Love, Buffalo, NY.
Frederick Post #1444P, 5" scales
White, plastic, linear, closed-frame, simplex rule with metal-framed glass cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. Top beveled edge has 12.5cm ruler, bottom bevel has 5" ruler. Ratty leather scabbard and rule are dirty. Hopp* doesn't list the "P" variation. Made in USA.
Frederick Post #1446, 10" scales
A linear, closed-frame, bamboo rule. Scales on front are A, [B, C], D. The slide rides on a flat metal bushing. On the back of the slide are S, L, T. The back of the rule shows weights, measures, conversion units, and some scale units. Housed in a cardboard sliding lid box. Given by Clayt Kramer, April 2000.
Frederick Post #1447, 10" scales
Linear, closed-frame bamboo rule very similar to #1446. Made in Japan by Hemmi, has "Sun" logo on front. Packed with instruction sheet indicating Sterling Co. is vendor. Front scales A, [B, CI, C], D, K. Back of slide has scales S, L, T. On the back of rule are some instructions, trig relationships, and conversion tables. Also has flat metal bushing under slide. This specimen, alas, lacks a cursor. Housed in cardboard sliding-lid box.
Frederick Post #1452W, 10" scales
Linear closed-frame plastic-coated wood. Top has beveled 10"scale, bottom shows 27cm scale on edge of rule. Back has imprinted "Sun" logo and "Hemmi JAPAN FH". Front scales are A, [B, CI, C], D, and K. Rear of slide has S, L, T scales. Rear of rule shows conversion tables, weights, measures, equivalents. et c. Housed in leather scabbard.
Frederick Post #1460 Versalog, 10" scales
White, celluloid-laminated wood, linear, open-frame, duplex rule with metal-framed cursor. Front scales: LL/1, LL/2, LL/3, [TT, Sec T ST, Cos S, C], D, LL3, LL2, LL1. Rear scales: LL0, LL/0, K, DF, [CF, CIF, CI, C], D, R1, R2, L. Serial (?) #806396. Heavy leather scabbard with belt loop. Made in Japan by Hemmi.
Hughes-Owens #341-3526, 10" scales
White, bamboo, linear, closed-frame, simplex rule with metal-framed glass cursor. Scales: A, [B, CI, C], D, K. Back of slide: S, L, T. Rear of rule has weights and measures, formulae, trigonometric relationships, and equivalents. A simple, well-made, easy-to-read rule manufactured in Japan by Sun Hemmi to Hughes-Owens specifications. Comes in a cardboard slip-top box. Not listed in Hopp*.
(innominate) #2010, 10" scales
10 inch scales. On front, scale is pencil-marked "A", another printed "P-1". Conversion units on back from US Bur. of Stds Circular No. 47. Back of slide has scales sin, 1g and 1g (smaller letters). Front of slide has 2 unmarked scales (B and C?). In cardboard box. Made in Germany. Has the name "Knox" written on front of rule.
Keuffel & Esser #4041, 10" scales
White-laminated, wood (mahogany? walnut?), linear, closed-frame, simplex rule - alas, no cursor. Scales: unmarked, but are probably A, [B, C], D. Back of slide: S, unmarked but probably L, T. On body under slide: a centimeter ruler from 28 to 52. Ten inch ruler at top of body on taper, centimeter ruler from 0-27 on bottom. The back of the rule has a list of values, ratios, and constants. Housed in a leather scabbard sans top.
Keuffel & Esser #4045, 16" scales
Top of rule has 16" beveled scale, bottom has 42 centimeter scale. Unmarked but probably A, [B, C], and D scales on front. Back of slide has S, L, and T scales. Weights, measures, and conversion units printed on back. Made of wood, probably mahogany. Cursor is missing (Damn'!). No case or manual.
K & E #N4053-2, 8" scales
White-plastic-laminated, wood (mahogany? walnut?), linear, closed-frame, simplex rule with metal-framed glass cursor. Scales: A, [B, CI, C], D, K. Back of slide: S, L, T. Referred to as Mannheim Polyphase. Serial #123496 on back of slide. Back of rule has "EQUIVALENTS AND ABBREVIATIONS FROM U. S. BUREAU OF STANDARDS CIRCULAR No. 47". Made in USA from 1909-1955. No case or box.
K & E #N4053-3 25cm scales (many K & E slide rules were made with 25cm scales, but are referred to as 10")
Linear, closed-frame, painted-mahogany, Mannheim, polyphase rule, serial #140968. Made from 1909-1955. Front scales A, [B, CI, C], D, and K. Rear of slide are S, L, and T. Back of rule shows conversions, measurements, et c. Cursor is missing.
K & E #4058, 25cm scales
Also called "Beginner's". Same as 4058 W except unpainted wood.
K & E #4058 W Beginner's Slide Rule, 25cm scales
Closed-frame, linear, white-painted wood. A, [B, C], and D scales on front. Back of slide has S, L, and T scales. Conversion units printed on back. In plastic case.
K & E #4081-3 Log Log Duplex Decitrig, 25cm scales
Open-frame linear plastic-coated wood rule. Scales on front are LL01,L, K, A, [B, T, ST, S], D,DI, LL1. Other side has LL02, LL03, DF, [CF, CIF, CI, C], D, LL3, LL2 scales. With manual, case with leather flap. Copyright 1947, ser.#898617 on slide.
K & E #4083-3, 25cm scales
White-faced wood, linear, duplex, open-frame rule with glass cursor. Front scales K, A, [CF, CIF, C], D, L. Rear scales DF, [S, T, CI], D. L-brackets at ends are tarnished. Scabbard case has no cover flap. Patent dates June 5, '00 and Dec. 22, '03.
K & E #4088-3 Polyphase Duplex, 25cm scales
White, plastic-laminated wood, linear, open-frame, duplex rule with plastic (?) cursor. Front scales: K, A, [B, S, T, CI], D, L. Rear scales: DF, [CF, CIF, C], D. Serial number 590737 on body and slide. Cardboard case with snap top (broken off). Made in USA to usual high K & E standard of quality.
K & E #4092-3 Log Log Duplex, 25cm scales
White, wood, linear, open-frame, duplex rule with plastic cursor. Front scales: LL0, A, [B, S, T, C], LL3, LL2, LL1. Rear scales: K, DF, [CF, CIF, CI, C], D, L. Serial #325530 appears on the slide and body of rule. Made in USA from 1909-1936. With leather scabbard marked 4092-3.
K & E #4097C, 5" scales
White, linear, closed-frame, plastic, simplex rule with metal-edged glass cursor. Obverse scales: A, [B, CI, C], D, K. Reverse slide scales: S, L, T. On back of rule are 13cm and 5" rulers. Serial number 89750 on body and slide. Made in USA. High quality pocket rule with nice leather scabbard. Given by Jack Love, August 2000.
K & E #4097D, 5" scales
White, linear, closed-frame, plastic, simplex rule, with metal-edged glass cursor. Obverse scales: A, DF, [CF, CI, C], D, K. Reverse slide scales: S, B, L, T. On back of rule are 13cm and 5" rulers. Serial number on slide and body 0044965. Made in USA. Typical K & E quality, with leather scabbard case.
K & E #68 1210 Log Log Duplex Decitrig, 25cm scales
White, linear, open-frame, laminated wood (walnut?), duplex rule with metal-rimmed plastic cursor. Serial #990679 on slide, #679 on each frame piece. Copyright 1947. With leather scabbard and K & E hard-cover instruction book "K & E Slide Rules Jetlog and Decitrig An Instruction Manual". Made in USA. Given by Jim Walker, Barberton, OH.
K & E #68 1608, 20" scales
White-faced, wood (mahogany?), linear, closed-frame, simplex rule with metal-framed glass slide. Scales: A, [B, CI, C], D, K. On rear of slide are S, L, T. On top bevel is 20" ruler, with 50cm ruler on bottom edge of rule. Serial #880260. Rule and scabbard in pristine condition - slide-in box is a little scuffed, but not bad. With small booklet "How to take care of your Slide Rule", by K & E. A real beaut of a slide rule.
K & E #68 1892 K-12 Prep, 25cm scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: K, A, [B, S, CI, T, C],D, L. Back of rule is blank. An inexpensive, Mannheim-type rule, with a plastic scabbard and instruction booklet. Made in USA. Not found in Hopp*.
Lafayette #F-340, 13cm scales
White, linear, bamboo, closed-frame, simplex rule with a metal-rimmed plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. A 5" ruler is on the bottom edge, and a 13cm on the bevel on the top edge. This rule strongly resembles a Sun Hemmi rule. Has a very nice leather scabbard case. Made in Japan.
Lawrence Engineering Service #10B, 9 1/2" scales
White, linear, wood, closed-frame, simplex rule with plastic, magnifying, metal-rimmed cursor. Front scales: A, [B, CI, C], D, K. No other scales appear on the rule.
Leitz #2974, 10" scales
White, wood, linear, closed-frame, simplex rule with metal-rimmed plastic cursor. Front scales: A, [B, CI, C], D, K. Back of slide: S, L, T. Rear of rule has weights, measurements, constants and equivalents printed directly on the wood. Very ordinary rule by A. Leitz Co. Made in USA.
M-41 Rules #1 & 2, 76mm gun-laying tables
White paper laminate on wood, with plastic cursor. Not a slide rule but table of values aligned by a cursor. Scales (6 sets on 2 rules): 100 YDS, RANGE, ELEV, F, DRIFT, FS. Scale sets marked N, R, and N. Both rules marked G. F. T. M41. Serial numbers 18078 (rule #1), 19078 (rule #2). Both rules housed in a canvas snap-top scabbard stencilled "CASE, CARRYING, M-67".
M-64 Rule #2, 155mm Howitzer gun-laying tables
Designated FT 155-Q-3, dated 29 JAN 60. This is not truly a slide rule, but a series of value tables aligned by means of a large, plastic, hairlined cursor (the only moving part) and used for aiming a 155mm field piece. Plastic with white paper scales laminated on each side, size about 1 1/2" x 15" x 1/8", approx. Scales (4 sets, 2 on each side) : DEFL CORR/DRIFT, 100/R, RANGE (METERS), EL, FORK, FS M520. Housed in a canvas snap-top scabbard, stenciled "CASE, CARRYING M86".
Marc #6, 13cm scales
White, plastic, linear, closed-frame simplex rule with metal-rimmed plastic cursor. Scales: Not marked, but appear to be K, A, [B, CI, C], D, L (marked). Rear of slide: S, (unmarked scale), T. Small logo on left lower front says "unis" and "France", with the numbers 48 and 18 beneath it. Has a 13cm ruler on bevelled top edge. With leather slip-in scabbard.
Micronta #505, 12.5cm scales
Linear, closed-frame bamboo rule. Front scales A, [B,CI, C], D, K. Back of slide S, L, T. Back of rule shows conversion tables, constants. Inches on bottom edge, centimeters on bevelled surface along top edge. Micronta is a house brand of Radio Shack. Made in Japan, has very smooth action. With quite nice leather case, instruction brochure, and box.
Morilla #881, 10" scales
White, wood, linear, closed-frame, simplex rule with plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. Back of rule shows equivalents, settings, and formulae. Morilla company was in New York, rule made in USA. This rule isn't listed in Hopp*.
Nestler #0232 Rietz, 25cm scales
White, linear, mahogany wood, closed-frame, simplex rule, with metal-rimmed glass cursor. Scales (not marked): K, A, [B, C], D, L. "L" scale is graduated in units slightly under 1 inch. Rear of slide: sin, sin;tg, tg. On bottom edge is a scale of units (marked 1:25) equal to approximately 1 9/16". On the top bevelled edge is a 27cm ruler. The rule is 1cm thick. The back of the rule has constants, equivalents, specific resistance, heat, gravity of various substances, all in German.
No name, no model #, 104mm scales
White, linear, closed-frame, simplex, wood rule with glass metal-rimmed cursor. Very cute little rule with minimal practical value. Obverse scales: A, [B, CI, C], D, K. No other scales. Made in Japan, with instruction sheet and clear plastic snap-top sheath. Most assuredly an "el cheapo" novelty rule.
No name, no model # New York Central, 5" scales
White, plastic, linear, closed-frame, simplex rule with a plastic, magnifying cursor. Scales: A, [B, CI, C], D, K. Back of slide: S, L, T. Sheath is marked "New York Central". Top of rule has 13cm ruler, bottom has 5" ruler. Undoubtedly a give-away for promotional purposes. Made in Japan.
Pickett & Eckel #N3-ES Power Log Exponential, 10" scales
Yellow, aluminum, linear, open-frame, duplex rule with plastic cursor. Also named "Log Log Dual Base". Front scales: Odd (digit/zero), K, A, [B, ST, S, T<45, T>45, CI, C],D, DI, Digits 1-4-7-10, Digits 2-5-8-11, Digits 3-6-9-12. Rear scales: LL0 +.001/<.001, LL1 +.01/-<.01, DF, [CF, CIF, Ln, L, CI, C], D, LL2+.1/-.1, LL3 +1.0/-1.0. Made about 1960 in USA, a complex rule. Has a very nice brown leather scabbard. Two specimens, one given by Jim Walker, Barberton, OH.
Pickett & Eckel #4-ES Dual Base Log Log Reciprocal Scale (Vector Hyperbolic), 10" scales
Yellow, aluminum, linear, open-frame, duplex rule with plastic cursor. Front scales: Digits 1-4-7-10 etc, Digits 2-5-8-11 etc, Digits 3-6-9-12 etc, DF,[CF, T, ST, S, CI, C], D, DI, Odd (digits/zero) nos. Rear scales: LL1 (+/-), LL2 (+/-), DF/M, [CF/M, TH, SH, L CI, C], D, LL3 (+/-), LL4 (+/-). With leather scabbard. This is near the top of Pickett's slide rule line.
Pickett & Eckel #80, 10" scales
Linear, open-frame, plastic simplex. Front scales are T, K, A, [B, CI, C], D. Printing on this specimen badly worn. Cursor is scuffed. In general, this rule is nasty.
Pickett & Eckel #103ES, approx. 10" outer scale.
Circular, yellow, aluminum, duplex rule with plastic cursors (2). Front scales: C, CL, A, AF, L, F. Rear: Cost,Selling Price, Cost/sell. Price % Basis. Comes in round leather case. Given by Pat and Milan Zivick, Reno, Nevada.
Pickett & Eckel #120 Trainer, 10" scales
White, plastic, linear, open-frame, plastic simplex rule with plastic cursor. Several specimens, many badly worn. Front scales are K, A, [B, T, S, CI, C], D, L. Rear of rule is blank. Many cursors are badly scuffed; nasty-looking specimens. With slip-in cardboard scabbard
Pickett & Eckel Microline #121, 10" scales
Open-frame, linear plastic simplex rule w/ plastic cursor. Scales printed on front K, A, [B, T, S, CI, C], D, L. On the rear are weights, measures, and conversion tables. This specimen has a badly-scratched cursor (definitely due to design problems), is dirty, and some printing has dimmed. Sad. No case or manual.
Pickett & Eckel #125, 10" scales
White, plastic, linear, open-frame, duplex rule with plastic cursor. Front scales: K, A, [B, CI, C], D, L. Rear scales: [S, ST, T, C], D. Back of rule has decimal equivalents. Inexpensive, made in USA. With cardboard scabbard. Not listed in Hopp*.
Pickett & Eckel Microline #140, 10" scales
Open frame, linear yellow plastic duplex rule w/ plastic cursor. Front scales are LL0, LL00 A, [CF, CIF, CI, C], D, K. Rear scales are L, LL1, DF, [B, S, ST, T, C], D, LL3, LL2. Cursor badly scratched, rule is dirty, and some printing dimmed on front and back. Cursor scratching due to design problem. No case or manual.
Pickett & Eckel Microline #160, 10cm scales
Yellow, plastic, linear, open-frame, simplex rule with plastic cursor. Front scales: K, A, [B, CI, C], D, L. Rear of rule is completely blank. With a leather-like plastic scabbard.
Pickett & Eckel #N200-ES Trig, 5" scales
Yellow, aluminum, linear, open-frame, duplex rule with plastic cursor. Front scales: K, A, [B, CI, C], D, L. Rear scales: [B, ST, T, C], D. Housed in a very nice leather scabbard, with instruction booklet and slide-in box. Given by Don Brodzik July 2000 for Meritorious Service Above and Beyond the Call of Duty (ABCD). Thanks, Don.
Pickett & Eckel #N-500-ES, 10" scales
Yellow aluminum linear open-frame duplex. Front scales are +LL1, -LL1, A,[B, T, ST,S, C], D, +LL3. Back scales are +LL2, -LL2, DF,[CF, CIF, L, CI, C], D, +LL3, -LL3. This rule is in excellent condition. Action is smooth. This specimen has a very nice leather scabbard, no instruction book. Made in USA. Second rule of this model has the leather scabbard, manual "HOW TO USE LOG LOG SLIDE RULES", and slide-in box.
Pickett & Eckel #500-T, 10" scales
White aluminum linear open-frame duplex. Front scales are LL0, LL00, A,[B, ST, T, S, C], D, K. Back scales are L, LL, DF,[CF, CIF, CI, C], D, LL3, LL2. Action is slightly sticky. This specimen has a worn leather scabbard, no instruction book. Made in USA. Given by Ted Ignatov.
Pickett & Eckel #N-515-T Electronic, 10" scales
White, aluminum, linear, open-frame, simplex rule with plastic cursor. Obverse scales (left end markings): (Lp) H, (fx) 2pi, A, [(Cr) B, S, T, (Lx or Cx) CI, xL or fp-C], D, L, Ln. (right end markings) 1/(2pi)^2x^2, x/2pi, x^2,[x^2, sin x, tan x, 1/x, xvL or fvR], xvC, logv10 x, logv6 x. Back of rule has formulae and problems in reactance, resonance, temperature, inductance, Ohm's law, decibels, frequency, wavelength, power factor, resistance, et al. Has black leather scabbard. Copyright 1962 by Cleveland Institute of Electronics, Cleveland 14, Ohio.
Pickett & Eckel #N700-T USAF Aerial Photo, (nominal) 6" scales
White, aluminum, linear, open-frame, duplex rule with plastic cursor. Front scales: L, A, DF, [CF, CIF, T, S, C], D, DI, K. Rear scales: Ground Size (feet), [Image Size (cm), Image Size (feet), Focal Length inches], Altitude (feet). Through a window on the back of the leather scabbard case are shown equivalents, settings, and geometric formulae. The rule, in pristine unused condition, comes with a USAF tech manual copyrighted 1951. The scabbard has a pocket clip. This is a specialized rule for aerial photograph analysis, is in a plastic wrapper, and the rule and manual are in a slide-in cardboard box. A beautiful set. This rule not mentioned in Hopp*.
Pickett & Eckel #800-ES Log Log, 10" scales
Yellow, aluminum, linear open-frame, duplex rule with plastic cursor. Also named "Synchro-Scale". Front scales: LL1(+-), A, [B, ST, T, S, C], D, DI, K. Rear scales: LL2(+-), DF, [CF, CIF, L, CI, C], D, LL3(+-). With excellent leather scabbard.
Pickett & Eckel #800-T Log Log, 10" scales
White, aluminum, linear, open-frame, duplex rule with metal and plastic cursor. Front scales: LL1(+-),A,[B, ST, T, S, C], D, DI, K. Rear scales: LL2(+-), DF, [CF, CIF, L, CI, C], D, LL3(+-). Same rule as #800-ES except rule is white. With leather scabbard.
Pickett & Eckel #N803-ES Log Log Dual Base Speed Rule, 10" scales
Yellow, aluminum, linear, open-frame, duplex rule with plastic cursor. Front scales: >>, K, A, [B, S, ST, T, CI, C], D, DI, DFn. Rear scales: LLO+-, LL1+-, DF,[CF, CIF, L, CI, C], D, LL2+-, LL3+-. ">>" scale on the front of the rule is a 20" scale divided at 3.165, and beneath it the second 10" from 3.165 to 10. With leather scabbard.
Pickett & Eckel #901, 10" scales
White, linear, closed-frame, simplex rule. Scales: A, B, 1/c, C, D, and K. Back (incl. slide) shows instructions for use, definitions, and Pickett & Eckel, Alhambra, Calif. USA, 21. No case or manual.
Pickett & Eckel #N902-T Simplex Trig, 10" scales
White, linear, aluminum, simplex; plastic cursor is lightly scuffed but easily readable. Front scales K, A, [B, T, S, CI, C],D, L. Back of rule shows rather detailed instructions and decimal equivalents of fractions. With sleeve case. Made in USA.
Pickett & Eckel #903-T, 10" scales
White, aluminum, linear, open-frame, simplex rule with plastic cursor. Scales: K, A, DF, [CF, T, S, CI, C], D,L. Back of slide has linear, liquid, energy and miscellaneous equivalencies and relationships. This rule has many tiny formulae written in a very tiny hand on both sides. With a slip-in cardboard scabbard.
Pickett & Eckel #1000 Ortho-phase, 10" scales
White, linear, aluminum, open-frame, duplex slide rule with plastic and metal cursor. Front scales: A,[B, T, ST, S], D, K. Rear scales: DF, [CF, CIF, CI, C], D, L. Copyright 1948, serial number on bottom of cursor D2B3046. With felt sleeve case.
Pickett & Eckel #1006-T Trig, 5" scales
White, aluminum, linear, open-frame, duplex rule with plastic cursor. Obverse scales: K, A, [B, ST, T, S, C], D, DI. Reverse scales: Ln, D, F, [CF, CIF, CI, C], D, L. Copyright 1959. With leather scabbard case w/pocket clip, two booklets "how to use ... Trig SLIDE RULES", and "how to use ... Dual Base SLIDE RULE EXPONENTIAL Ln-L SCALES", all in push-in box.
Pickett & Eckel #1010, 10" scales
Same as #1010-ES except white. This specimen has a sticky slide, otherwise in good shape. Given by Jack Love, Buffalo, NY.
Pickett & Eckel #1010-ES, 10" scales
Same as #N1010-ES except standard cursor.
Pickett & Eckel #N1010-ES, 10" scales
Yellow, linear, aluminum, open-frame, duplex rule with plastic cursor. Obverse scales: K, A, [B, ST, T, S, C], D, DI. Reverse scales: L, DF, [CF, CIF, CI, C], D, DI. Back of slide says Copyright 1959, patent applied for. Other end has Pickett logo with "74" over it. Has a gorgeous brown leather scabbard case.
Pickett & Eckel #1010-T, 10" scales
White, linear, aluminum, open-frame, duplex rule. Front scales K, A, [CF, CIF, CI, C], D, DI. Rear scales DF, [B, ST, T, S, C], D, L. Right side of slide says "Pickett & Eckel 271". Rear of slide has logo with a small "74" above it. Has a rather nice California saddle leather scabbard.
Relay #102, 10" scales
White, bamboo, linear, closed-frame, simplex rule with metal-framed glass cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. Also numbered TL-213 and H.K-4. Housed in cardboard slip-top box. Made in Japan probably after 1954. Not listed in Hopp*.
Relay #403, 4"scales
White, bamboo, linear, closed-frame, simplex rule. Scales: A, [B, CI, C], D. Rear of slide: S, L, T. Bevel on top edge of rule has 5" ruler, bottom edge has 10cm ruler. Back of rule shows conversions, equivalents, and formulae. Very nice small rule with a very nice leather scabbard. Cursor missing (snookered yet again by the hucksters). Not listed in Hopp*.
Staedtler #969, 25cm scales
White, plastic, closed-frame, linear, duplex rule with plastic cursor. Front scales: K, A, [B, CI, C], D, L. Rear scales (all stationary): Centimeter ruler, S, ST, LL1, LL2, LL3, Inch ruler. Rear of slide has a Greek alphabet with English names of the letters. Housed in a clear plastic box. Made in Germany. Not listed in Hopp*.
Sterling "Decimal Trig Log Log" (no model #), 10" scales
White, plastic, linear, open-frame, duplex rule with plastic cursor. Front scales: LL01, K, A, [B, T<45, T>45, ST, S], D, DI, LL1. Rear scales: LL02, LL03, DF, [CF, CIF, L, CI, C], D, LL3, LL2. Inexpensively made; copyright 1965, made in USA. With plastic scabbard and instruction booklet.
Sterling "Precision" (no model #), 30cm scales
Also called "10 inch Senior Mannheim". Semi-open frame, linear plastic rule, plastic cursor. Cheaply made. Scales on front are A, [B, CI, C], D, K. Back of slide shows S, L, T. With plastic scabbard, instruction pamphlet.
Sterling #584, 10" scales
White, plastic, linear, open-frame, simplex rule with plastic cursor. Scales: A, [B, CI, C], D, K. Rear of slide: S, L, T. Has a clear hard-plastic scabbard and instruction sheet. Made in USA.
Sterling #587, 5" scales
White plastic linear closed-frame simplex, plastic cursor. Front scales A, [B, CI, C], D, K. Back of slide has S, L, T. Small, simple, easy-to-read rule. This specimen has no case nor instruction book. Made in USA.
Sterling #594, 30cm scales(?)
Linear, open frame, white plastic duplex rule with plastic cursor. Front scales are LL02, LL03, DF, [CF, CIF, L, CI, C], D, LL3, LL2. Reverse side shows LL01, K, A, [B, T<45, T>45, ST, S], D, DI, LL1. With plastic slip-in sleeve case.
Sterling #684, 10" scales
White, linear, closed-frame, simplex rule with plastic cursor. Also labeled "Basic Mannheim" and "Precision". Obverse scales: A, [B, CI, C], D, K. Reverse of slide: S, L, T. This specimen still in its original packaging, with instruction sheet. Made in USA after 1968 by Sterling Plastics Co. of Mountainside, NJ. Original retail price $1.29.
Tata, E. #522, 10" scales
White, wood, linear, closed-frame, simplex rule with metal-framed glass cursor. Scales: A, [B, CI, C], D. Rear of slide: S, L, T. Top and bottom of rule joined by metal strip. Bevel at top of rule has 10" ruler, bottom edge of rule has 27cm ruler. With cardboard case. Made in Japan.
Unique #1140 Students, 5" scales
White, plastic-laminated wood, linear, closed-frame, simplex rule with plastic cursor. Scales: LU, A, [B, C], D, LL. Back of rule has sine and tangent values for each degree of angle from 1-90, to 3 or 4 decimal places. Housed in a cardboard slip-in box. Made in England rather cheaply.

*Hopp = "SLIDE RULES, Their History, Models, and Makers", by Peter M. Hopp.

Non-slide rule devices

In human history there have been many methods used to achieve addition and subtraction. The abacus is one of the more persistent and pervasive devices, having been in use in several parts of the world from ancient times until the modern day. While mainly used for addition and subtraction, it is also useful in multiplication and division. The operator uses the abacus as a memory aid for keeping track of the progress of the computation, while supplying his own brainpower for most of the work. The soroban is the Japanese version of the abacus. The origins of this tool are lost in pre-history.

Soroban #55 (manufacturer unknown). In original box
Japanese calculating device also known as the abacus. I purchased this soroban at a small stationery store in Tachikawa, Japan, about 1959. It cost 250 yen (about 70 cents, quite a high price at that time). Hand-made of a very dark wood, with lighter wood units and fives wheels on bamboo axles. About 12.5 x 2.75 x .75 inches. Objects of this nature were often hand-made in the home, rather than in a factory. Soroban users were very adept, and could do math problems with startling speed. Instruction book in English "The Japanese Abacus", by Takashi Kojima, 1954.
Soroban (manufacturer unknown).
Another Japanese calculating device also known as the abacus. This specimen is about 60x220x15 millimeters; the frame is very dark wood, lighter wood units and fives wheels on bamboo axles. As you may have guessed, the main difference in sorobans is in the size. No box or instructions with this one. A skilled user could calculate even without the soroban, making all the finger movements while IMAGINING the soroban!! Made in Japan.
Soroban (manufacturer unknown).
Smaller soroban, about 60x120x14 millimeters. Dark wood frame, very light wood units and fives wheels on brass axles. This rascal has 5 units wheel on each axle - I don't know what this variation is for. In Japan sorobans were used in retail businesses to tally the bill, and the results were then rung up on a modern cash register, which stored the money. Made in Japan.

SLIDE RULES FOR TRADE I have a number of duplicate rules in my collection which I would like to trade for rules I don't have. What have you?
Pickett N3-ES - good shape, leather scabbard, slight wearing near one end of rule.
Pickett N-500-ES (2 extra) - both very nice, with leather scabbard cases
Pickett 120 - (several) These are very bad. Mostly useable, but badly worn, with scuffed-up cursors. "Nasty" is a good operative term here. Re-inking may be possible in some cases, but don't count on it. They can be used to hold the screen door open so the cat can get out. All have plastic slide-in scabbards.
K & E 4058W - good shape, cursor has some rust specks. No case nor instructions.
K & E 4088-3 - nice rule, good shape. Case is missing top flap.
Sterling "Decimal Trig Log Log" (no model #) - Excellent shape, with sleeve case.

A listing of my slide rules

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Additional Links to Various Slide Rule Pages
Kung's Slide Rule Site
R. E. Manley's Slide Rule Site
Link to H-P Slide Rule museum
Dave's House Of Slide Rules

This page last updated on 23 Oct 2004 by Cal Clifford, page author.

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