Rarities, Olde and Rare Logarithmic Calculators
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This page contains slide rules that are very rare, hard to find or manufactured in the 1800's, earlier and later, but prior to WWII, using turn of the century materials and process. These may include Boxwood, Ivory (Bone), Brass and in many instances were hand-divided by an artisan. Thanks to the members of the UK Slide Rule Circle, the Dutch KRING and the Oughtred Society for most of the scans provided in this gallery. Some images provided by major museums.

Many of these images in the ISRM galleries, also appear in the Oughtred Society's Rarities Gallery, which displays rare, not necessarily old, specimens in collections of active members's of the Oughtred Society. This gallery is being compiled by Ted Hume and Rod Lovette.

In some cases there are historical or photographic records of logarithmic slide rules but the actual artifact has not been found. In the example on the right a photo from 1908 shows a Cylindrical Slide Rule comprising two wheels with scales on the outside edge. Each can rotate separately from the other, with a foot operated brake to lock the wheels while transfering calculations. The diameter looks to be about 4 feet which gives a scale length of 150 inches, or 15 times the length of a standard slide rule. The wheels and base appear to be made of cast iron. This unique design which is wildly different than any of the designs that made it into broad production, was quickly made obsolete by other designs that were cheaper to make and had a higher resolution in the scales like the Billeter, Loga, Thacher, Fowler and many others. One cannot be found, simply because the iron was too valuable, and was probably melted down to supply metal for the first world war.
In conjunction with the 'donors' the OS assigns a rarity rating to each item, based on the system devised by Herman van Herwijnen (1929 - 2004), renowned Dutch collector, author, and creator of Herman's Catalogue.
• RR = Rare - 1 of 25 collectors has one; it may take a year to find an example in the marketplace.
• RRR = Very Rare - only a few known to collectors; may be several years before it comes up for sale.
• RRRR = Extremely Rare - a museum piece; unlikely that an example will come up for sale.

Napier's Bones (Rods)

Lord John Napier (latinized Nepero), Baron of Merchiston, Edinburgh, Scotland. Published the logarithm in 1614, after 20 years of developing the tables, which made it possible to perform multiplications and divisions by addition and subtraction and was the foundation for all future slide rule designs. Ex: a*b = 10^(log(a)+log(b)) and a/b = 10^(log(a)-log(b)). He created this calculating tool, which is easy to build out of square dowels.

John Brown Circular Slide Rule

A circular slide rule, made by John Brown, with two brass radial arms and an astronomical quadrant engraved on the back. A spiral slide rule affords a long and therefore accurate logarithmic line in a small amount of space. The potential of spiral rules was not really utilized until the Victorian period, when several spiral and helical designs appeared on the market. Sciencemuseum.org.uk archive #1954-433.

Gunter's Scale

This is the predecessor of the modern slide rule. created by Edmund Gunter. A pair of dividers is used to measure a distance (the multiplicand and the multiplier) along the rule and add it to another distance, the multiplicand, forming the combined distance, the product, on the rule. The accuracy of an answer is limited by the length of the rule and the user's ability to resolve a number.
Gunter's Scale - Two Foot


Table of Trigonometry, from the 1728 Cyclopaedia,
Volume 2 featuring a Gunter's scale

 Gunter's Scale - Two Foot - Circa Early 1800's
Made in UK - Made of Boxwood
Front Scales: RUM, CHO, SIN, TAN, S*T, SEC, RUM, M*L, CHO, 24 inch and decimal foot, 1/2 inch and 1 inch diagonal scales.
Back Scales: S*R, T*R, NUM, SIN, V*S, TAN, MER, E*P.
Note: This is the most common Gunter Scale, used for navigation
Archive - David M. Riches Collection (UK)


Gunter's Scale - One Foot 		Gunter's Scale - One Foot - Circa Early 1800's
Made in UK - Made of Boxwood
Front Scales: (Left) RUM, CHO, SIN, TAN, S*T, (Center) SEC, (Right) S*R, T*R, NUM, SIN, V*S, TAN, MER, E*P, LEA, RUM, M*L, CHO.
Back Scales: 12 inch and decimal foot, 1/2 inch and 1 inch diagonal scales.
Note: The upper side has brass pins insert at the scale starts and some gauge points to protect the rule from the divider points at these frequently used places.
Archive - David M. Riches Collection (UK)

Sectors

Galileo Galilei (1564-1642) Popularized the sector at the very end of the 16th Century. The sector is a graduated ruler that uses trigonometric formulae and a caliper to calculate squares, cubes, reciprocals and tangents of numbers. Galileo's design of the sector as a mathematical tool can be seen as the moment when calculation aids cease to be based upon counting and instead exploit the deeper relationships among numbers. His invention is still in use as a navigation aid in the 20th century 300 years later.(ref: Oughtred Society) Sectors were frequently included in sets of drawing instruments in the eighteenth and nineteenth centuries until made obsolete by the slide rule. There are three types of scale on an English sector: sectoral ones (radiating from the hinge centre), which were used for calculation; plane scales (logarithms, sines, tangents) parallel to the edge; and rules (inches, tenths of feet). Most were six inches in length. A few images from David M. Riches website. Read this excellent paper on Edmund Gunter and the Sector written by C. J Sangwin, of the University of Birmingham, UK.


ISRM - Ivory Sector (150dpi)
Hi-res Image (300dpi)
Ivory Sector rotated open

Ivory Sector rotated straight to use as 12 inch scale 		Ivory Sector
Assumed to be made in UK by W&S Jones, No 135 Holburn, London, England Typical nineteenth century sector, having scales for inches, decimal feet, lines of sines, tangents, equal parts, chords, numbers (log scales for multiplication), polygons, secants.

Identical to the W&S Jones, David Riches Collection, shown below, but without manufacturer's identical and model markings.

Ivory Sector 3 'stars' identification marks



ISRM - Boxwood Sector (150dpi)
Hi-res Image (300dpi)
Boxwood Sector rotated open

Boxwood Sector rotated straight to use as 12 inch scale 		Boxwood Sector
Assumed to be made in UK. Typical nineteenth century sector, having scales for inches, decimal feet, lines of sines, tangents, equal parts, chords, numbers (log scales for multiplication), polygons, secants. This one, with the protractor was acquired from England.


Boxwood Sector single
'star' identification mark
Boxwood Protractor used
withe Sector in Navigation
and calculations



W&S Jones Sector 		W&S Jones Sector
Made in UK by W&S Jones, No 135 Holburn, London, England
Ivory sector. William & Samuel Jones were at this address from 1792 to 1800. This is very typical of nineteenth century sectors, having scales for inches, decimal feet, lines of sines, tangents, equal parts, chords, numbers (log scales for multiplication), polygons, secants.
Archive - Image and comments donated by David M. Riches


French Sector 		French Sector
Made in France. A brass sector dating from the eighteenth century with scales for line of equal parts, polygons, line of chords, metals, weights of shot and gun calibre. Unlike English sectors, which were used for general calculation, the French ones were generally intended for gunnery calculations.
Archive - Image and comments donated by David M. Riches


4-1/2 Inch Basswood Sector 		4-1/2 Inch Basswood Sector
Made in UK dated from the nineteenth century. Sectors were made in various sizes, but most commonly by far in the six inch size. The smaller, 4 1/2 inch ones would have been made to go with small size instruments, probably a pocket set. The scales are the usual English ones.
Archive - Image and comments donated by David M. Riches


Elliot Brothers Ivory Sector 		Elliot Brothers Ivory Sector
Made in UK by Elliott Bros, Strand, London dating from between 1854 and 1880. This is very typical of nineteenth century sectors, having scales for inches, decimal feet, lines of sines, tangents, equal parts, chords, numbers (log scales for multiplication), polygons, secants. It is a six inch size example.
Archive - Image donated by David M. Riches

Joint Rules (with Gunter Scales)

The first widely used standard form for a logarithmic slide rule is the two-foot, two-fold design devised by Henry Coggeshall around 1677. This was made in many variants by numerous makers, and is relatively easy to come by even today. Folding joint rules were in common use in the 1800's by capenters and other artisans. The addition of a sliding brass slide with logarithmic, or 'Gunter' scales to one leg of the joint rule added a calculation feature not found on the other similar looking devices. The back of the brass slide was divided into inches which allowed the user to use that part of the rule as a depth gage. When unfolded 180 degrees the rule became 24 inches long, not counting the slide length. Joint rules that are all linear, not having any logarithmic scales, are not included in the ISRM galleries.


ISRM - Carpenters Joint Rule with Gunter's scale on Slide - Unfolded


ISRM - Carpenters Joint Rule with Gunter's scale on Slide - Folded
 Carpenters Joint Rule with Gunter's scale on Slide
Made of boxwood with brass joint and Gunter's slide, c1890.
Front Scale (Top Leg): 12" decimal scale 1/16th increments || A (1-10-100) [ B (1-10-100) C ] D (4-10-40), Girt Line
Front Scale (Lower Leg): 1/2:1 Architectural scale. 1/4:1 Architectural Scale, 12" scale 1/16th increments
Back Scale (Top Leg):Fractional Measuring Scale 12 - 24 inches.
Back Scale (Lower Leg):Fractional Measuring Scale 1 - 12 inches.
Back Slide: :Fractional Measuring Scale 1 - 12 inches.
Markings: Warranted Best - Box, RD NO 28060, Improved Joint
Note 1: the D scale from 4 to 40 is based on the Coggeshall design.
Note 2: The Girt line below the slide, is used in calculating the volume of timber
('girt' is a quarter of the circumference of a round log).
Note 3: The Gunter's scale is in the format defined by Coggeshall in the 1600's


ISRM - Stanley No 15 Engineers Joint Rule with Gunter's scale on Slide - Folded
 Stanley No 15 Engineers Joint Rule with Gunter's scale on Slide
Made of boxwood with brass joint and Gunter's slide, c1890.
Front Scale (Top Leg): 12" decimal scale 1/16th increments || A (1-10-100) [ B (1-10-100) C ] D (4-10-40), Girt Line
Front Scale (Lower Leg): 1/2:1 Architectural scale. 1/4:1 Architectural Scale, 12" scale 1/16th increments
Back Scale (Top Leg):Fractional Measuring Scale 12 - 24 inches.
Back Scale (Lower Leg):Fractional Measuring Scale 1 - 12 inches.
Back Slide: :Fractional Measuring Scale 1 - 12 inches.
Markings: Warranted Box wood
Note 1: the D scale from 4 to 40 is based on the Coggeshall design.
Note 2: The Girt line below the slide, is used in calculating the volume of timber
('girt' is a quarter of the circumference of a round log).
Note 3: The Gunter's scale is in the format defined by Coggeshall in the 1600's

Issac Aston, Maker



Issac Aston 4-Sided_Box Rule 		Issac Aston 4-Sided_Box Rule
Made in UK by I. Aston Maker, 25 Old Compton Street, Soho, London c1860
Everard type made of boxwood
Side A: ? [ B ] D, on slide: { formula for cask volumes ]
Side B: SegST [ C ] SyS
Side C: A [ C ] D
Side D: Seg Ly [ B ] Sy, on slide: [ ?, Sp D, Variety]
Archive - Tom Dilatush Collection


Issac Aston Coggeshall 		Issac Aston Coggeshall
Carpenter's slide rule by Isaac Aston, London (working 1851-70), made of boxwood and brass with steel end caps. Isaac Aston (25 Old Compton Street, Soho, London) was succeeded by Aston & Mander. A two foot two-fold rule.
Archive - Tom Dilatush Collection

Aston and Mander Makers

Aston & mander Makers, 25 Old Compton St., Soho, London



Aston & mander Makers - Harrow Mark Reducer
ISRM 13.03.27.01
Slide rule, Harrow Mark Reducer, single-sided, open frame, wood / brass, straps, made by Aston & Mander, Soho, England, 1875 through 1925

According to Christopher Tyerman: A History of Harrow School, Oxford University Press, 2000. p.312. this slide rule was invented, c.1875, by Rev. William Done Bushell (1838-1917) of the Harrow School, as a special purpose slide rule to assist in the adding up of the weighted marks for school examinations. Rev. William Done Bushell who for fifty years was an assistant master and Honorary chaplain at Harrow School, was also lord of the manor of Caldey Island, Pembrokeshire. His son was Warin Foster Bushell (1885-1974).

Dimensions: The stock is 24 inches long, 1-78 inches wide, and 3/16 inch thick. The slide is 36 inches long and 5/8 inches wide.
The scales are log scales of, on the stock, two cycles and, on the slide, three cycles allow the reduction of any number from 2 - 2000 by a fraction ranging from 1 - 10.



Aston & Mander Makers - Carter's Rivet Pitch Calculator 		Aston And Mander Makers - Carter's Rivet Pitch Calculator
Made in UK, London
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle


Aston And Mander Makers- Dixon Style Slide Rule 		Aston And Mander Makers - Dixon Style Slide Rule
Made in UK, 25 Compton ST, London
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle


Aston And Mander Makers - C. Hoare Slide Rule 		Aston And Mander Makers - C. Hoare Slide Rule
Made in UK, 25 Compton ST, London
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle


Aston And Mander Makers - Ship Tonnage Calculator 		Aston And Mander Makers - Ship Tonnage Calculator
Made in UK, for G.L. Watson Co.
Naval Architects and Surveyors
141 Sauchiehall Street, Glasgow
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle


Aston And Mander Makers - 1915 Artillery 		Aston And Mander Makers - - 1915 Artillery
Made in UK, London
Front Scale: Yards [ Minutes of Angle or Battery Range ]
Back scale: Yards [ Minutes of Angle ]
Archive - Scan donated by Clay Castleberry, California.


Aston And Mander Makers - Timber & Brick Pricing Rule 		Aston And Mander Makers - Timber and Brick Pricing Rule
Made in UK, 25 Compton ST, London
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle

T.C. Ballardie



T.C. Ballardie - Merchant Vessel Speed And Power Scale 		T.C. Ballardie - Merchant Vessel Speed And Power Scale
Made in UK, by F. Robson &Co., 46 Dean Street, Newcastle on Tyne
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle

George Bousfield's "Vade Mecum Slide Rule"



Bousfields "Vade Mecum Slide Rule" (c1890)
ISRM 13.04.26.01		 Bousfields "Vade Mecum Slide Rule"
Designed Expressly for the timber Trade by George Bousfield (1856-1902) (Rawdon, Leeds), Grimsby. Patent 12806. Adaptable to the Stone, Brick, Irone, Slate, Glass, and other trades.
Made in England. Patented 9th August 1887. #12806
Note: "Vade Mecum" is latin for "Goes with me", in other words he was marketing a very portable calculator in the 1890's.
Front Scale: 2/16in scale || A [ B, 12-24in, C ] D || 0-12in
Back scale: E, F [ G, G, H(OPS)(PTS), I ] J, K
Gifted to ISRM by Phillip Rodley of Upperhut, New Zealand
The picture below shows George Bousfield in 1887 using his slide rule
Instructions (7.82MB PDF)

Dring and Fage



Dring And Fage - Excise Officers Rule (c1868)
ISRM 11.12.12.01

Note: This is one of the oldest physical slide rules at ISRM.
It was used for cask gauging with additional rods.

 Dring And Fage - Excise Officers Rule
Made in UK, Tooley Street, London - Made of Boxwood. 9-1/2" x 2" x 1/4" thick
Front Scale: A [ C, C ] SL, 2nd V, 1st V, A [ C, C ] MD (Malt Depth)
Back scale: D1 (1-3.2) [ B, B] D2 (3.2-10), H3 V, Y2 V A [ B, B ] SS. SL (Segment Lying), SS (Segment Standing), MD (Malt Depth).
Top edge Scale: L (1 in long divisions 0 - 9.5), Sphd (Speroid, Linear 0 - 6.5), Variety (Linear 1 - 6.1)
Bottom Edge Scale: log (1-10), log 1.6 - 16).
Note 1: Scale. D1 and D2 are the two halves of an 18 inch long log scale
Note 2: Gauge marks are identified by brass pins pressed into the wood stock
Note 3: MB (Malt Bushel) gauge mark at 2219 denotes a post-1824 rule.
Note 4: Embossed with the symbol of Inland Revenue, which occured after 1849
Note 5: It must be earlier than 1880 as it has the malt depth scale and they moved from Tooley street to The Strand in 1883.
Note: 6: For another example see Ron Manley's collection.
Note: 7: For more information on Gauging see Ron Manley's web page on gauging.


Dring And Fage - Brewers Slide Rule 		Dring And Fage - Brewers Slide Rule
Made in UK
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle




Dring And Fage - Brewers Slide Rule Set 		Dring And Fage - Brewers Proof Slide Rule Set
These ivory rules would have come from a Sikes Hydrometer case and are a Proof rule and a Comparative rule. Made in UK
Front Scale: TBD
Back scale: TBD

F.C. Farmar 10 Glouster Terrace, Thorpe Bay, Essex, England



Farmar's Desk Size Gauging Rule 		Farmar's Desk Size Gauging Rule
Made in England - Serial Number 8264
Front Scale (Guaging & Stocking): A [ B, C ] D, E, F
Back scale (Reducing): G [ H, I ] J, K, KK
Edges: Equations and Equivalents
Archive - Scan by Peter Fox, UK.

Froude



Froude's Slide Rule
Froude's Slide Rule
Made in England, Mfg by Stanley Great Turnstile, Holborn, London, England
Front Scale: K [ K, C ] D
Back scale: A [ B, C ] D
Edges: Equations and Equivalents
Archive - Scan by Peter Fox, UK.

Fuller



Fuller Rotary Calculator
ISRM 12.01.03.01 		Fuller Rotary Calculator
Made in United Kingdom - Designed by Prof. Fuller
Original owner in UK

Gravet Lenoir



Gravet Lenoir 		Gravet Lenoir - c1900
Made in France - 14 Rue Cassette, Paris
Front Scale
25cm // A [ B, B ] D || 25cm
Back Scale (Slide): [S, T, L ]
Well: 25-52cm
Archive - Clay Castleberry Collection

Hannyngton



Hannyngton (Astronomical) Slide_Rule

John Caufield Hannyngton
(1807-1886) 		Hannyngton (Astronomical) Slide_Rule
Made in England, Mfg by Aston-Mander
Size: 32 inchesa x 7.5 inches x 3/4 inch
Archive - Scan by Rod Lovette, UK.
Designed by Major-General John Caufield Hannyngton and is used in astronomical computations. Fellow of the Institute of Actuaries. His best known and largest work is a Table of Haversines, Natural and Logarithmic, used in computing distances for the Nautical Almanac.

Loftus



Loftus - Brewers Slide Rule 		Loftus - Brewers Slide Rule
Made in UK, London
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle

C. Mander



C. Mander Sliding Gauge Rule 		C. Mander Sliding Gauge Rule
Made in UK, London
Front Scale: TBD
Back scale: TBD
Archive - UK Slide Rule Circle

Palmer, Aaron

An early early version of the first circular slide rule published in America (first issued in 1843). Palmer and the engraver George Smith began working on their design for an "endless computing scale" in early 1841. It was copyrighted in Boston in late 1843, and versions of the device continued to be produced until at least 1852. Palmer's slide rule enjoyed only a limited success, largely because of poor marketing and the American public's fear that use of the device "[would] tend to weaken the mind, by causing it to rely upon mere mechanism to make its numbered computations" (Fuller, Key to Fuller's Computing Telegraph [1846], quoted in Feazel 1994, 15). Palmer also published A key to the endless self-computing scale, showing its application to the different rules of arithmetic (Rochester: P.S. Stoddard, 1842). Ref:Origins of Cyberspace 353.


Fullers Time Telegraph And Palmers Computing Scale 		Fullers Time Telegraph And Palmers Computing Scale
Made in Boston, United States - Pre 1840
Front Scales: Palmers Computing Scale
Back Scales: Fullers Time Telegraph
Notes: Made of cardboard, 8-1/2 inch diameter circular scale, on an 11 inch square base. Engraved by George G. Smith, 186 Washington, Boston, Massachusettes.
Archive - Scan by Clay Castleberry, California


Palmers Computing Scale - 11 Inch Square 		Palmers Computing Scale - 11 Inch Square
Made in Boston, United States - circa 1835
Front Scales: Palmers Computing Scale
Back: Instructions
Notes: Made of cardboard, 8-1/2 inch diameter circular scale, on an 11 inch square base. Engraved by George G. Smith, 186 Washington, Boston, Massachusettes.
Archive - Photo from 2009 Philip Weiss Auction


Palmers Pocket (endless) Scale 		Palmers Pocket (endless) Scale
Made in Boston, United States - 1845
Front Scales: Palmers Computing Scale
Notes: Made of cardboard, 80mm diameter. 143 x 91 mm. Engraved volvelle on heavy card mounted on rear pastedown of book "Palmer's Pocket Scale with Rules for its use in Solving Arithmetical and Geometrical Problems", Rochester, NY. Published by Aaron Palmer, Canfield and Warren Printers, 1845. Engraved by George G. Smith, 186 Washington, Boston, Massachusettes.
Archive - Photos by Clay Castleberry, California

McFarlane, Glasgow, Scotland


REF McFarlane's 6 inch Calulating Cylinder (1835)
 McFarlane's 6 inch Calulating Cylinder (1835)
Made by McFarlane, Glasgow, Scotland. Mid 19th century
McFarlane's Calculating Cylinder" (c. 1833), consisting of a cylinder with three separate revolving parts, on which are inserted several series of numbers, calculated to propose and answer questions to an almost indefinite extent in the first four rules of arithmetic. Note that this device does not utilize logarithmic scales. Made of paper covered turned mahogany, 6 3/8" long overall x 2 1/4" diameter, in 3 sections plus 2 threaded end pieces. There are two columns on the top section, one column on the center section, and three columns on the bottom section. The apparatus is designed facilitate calculations in interest on English money. It is one of the earliest examples of a handheld cylindrical calculating device.
Archive - Images from 2009 Phillip Wiess Auction, London Science Museum Collection, Gemmary,com
1833 at NMSI.UK

John Rabone & Sons



REF Rabone Joint (Carpenter's) Rule 		Rabone Joint (Carpenter's) Rule
Made by John Rabone & Sons, Birmingham, England. Late 19th century
It is a 2 foot, 2 fold example.The scales are few - only the 2-foot linear rule on the back and Coggeshall scales on the front: Three two-cycle logarithmic scales running from 1 to 100 above and on the slide, and a 4 - 40 "Girt line" below the slide, for calculating the volume of timber.
Archive - Image donated by Nathan Zeldes

W. Ransley



REF W. Ransley Slide Rule
W. Ransley Slide Rule
Made by W. Ransley Maker, Stangate, London, England circa 19th century
It is a 2 foot, 3 fold example.The scales are few - only the 2-foot linear rule on the back and Coggeshall scales on the front: Three two-cycle logarithmic scales running from 1 to 100 above and on the slide, and a 4 - 40 "Girt line" below the slide, for calculating the volume of timber.
Archive - Image donated by Nathan Zeldes

Edward Roberts, Makers

Edward Roberts was a British maker that produced gauger's rules from 1749-84 and his son Edward Roberts, Jr. continued the practice from 1788-96. Both father and son worked out of Dove Court, Old Jewry, London.


Edward Roberts - Everard Type Gaugers 4-sided Rule
ISRM 13.02.20.11 		Edward Roberts - Everard Type Gaugers Rule
Made in UK, London - c1749-1784
Scales: Wine and Ale Gallon Marks
Notes: The rare Roberts, London - Everard 4-sided type rule, with additional scales and tables on the back of each slide, has wine and ale gallon marks so is certainly pre 1824 and most likely second half eighteenth century as Roberts would either have been Edward Roberts (1) working 1749-84 or his son Edward Roberts, Jr. (2) working 1788-96, both at Dove Court, Old Jewry, London. In this artifact, there is no 'Jr. after the name, so it assumed it was made by the father. Ref. G C Clifton's Directory of British Scientific Instrument Makers p234. (per David M. Riches)


Roberts - Everard Type Gaugers Rule 		Roberts - Everard Type Gaugers Rule
Made in UK, London - Pre 1824
Scales: Wine and Ale Gallon Marks
Notes: The rather nice Roberts, London - Everard type rule has wine and ale gallon marks so is certainly pre 1824 and most likely second half eighteenth century as Roberts would either have been Edward Roberts (1) working 1749-84 or his son Edward Roberts (2) working 1788-96, both at Dove Court, Old Jewry, London. Ref. G C Clifton's Directory of British Scientific Instrument Makers p234. (per David M. Riches)
Archive - UK Slide Rule Circle

R.H. Smith



R.H. Smith Cylindrical Slide Rule		 R.H. Smith Cylindrical Slide Rule
Helical scales
Made by J.H. Steward
Archive - Conrad Schure Collection

Tavenier - Gravet



Tavenier-Gravet 		Tavenier-Gravet - c1900
Made in France- Rue Mayet 19, Paris
Front Scale
25cm // A, DF [ CF, CI, C ] D \\ 25cm
Back Scale (Slide): [S, L, T ]
Cursor: Brass Chisel Point
Archive - Rod Lovett Collection

K&E Thacher's Calculating Instrument



K&E 4012 Thacher's Calculating Instrument 		K&E 4012 Thacher's Calculating Instrument
Made in USA - Designed by Edwin Thacher
Archive - Michael O'Leary Collection (USA)

J. Thomlinson Ltd.


Thomlinson's Equivalent Paper Slide Rule (Version 1) 		Thomlinson's Equivalent Paper Slide Rule
Made in UK, J. Thomlinson Ltd. Publishers, Partick, Glasgow
Scales: 23in, A(Length) [ B(Breadth), Index ] C(area)[ D(Weight)] E(Standard Bulk Paper sizes L x W), Conversions
Archive - Scan donated by Peter Fox, UK
Thomlinson's Equivalent Paper Slide Rule (Version 2) Thomlinson's Equivalent Paper Slide Rule
Made in UK, J. Thomlinson Ltd. Publishers, Stanley Works, Partick, N.B.
Scales: A(Length) [ B(Breadth), Index ] C(area)[ D(Weight)] E(Standard Bulk Paper sizes L x W)
Note: Scales arranged by John Rennie
Archive - Scan donated by Peter Fox, UK

Forrest M. Towl

Forrest Milton Towl - (1836-1934) United States - Entrepenuer, Author, Petroleum Engineer. Designed and copyrighted (1889 & 1910) a Pipe Line Flow slide rule which was used in calculations involving the pumping of oil A 1910 version was used in the transportation of oil. See his expanded biography in the ISRM Who's Who Gallery


Forrest M. Towl Pipe line Flow Slide Rule

Left: Mineral Industry, 1920, Page 472
Right: Handbook of Petroleum Industry, 1922, page 403

Note: This slide rule design and layout was used as the basis for the Dow Chemical Slide Rules made by Pickett, Model 1060.

Forrest M. Towl Pipe line Flow Slide Rule
Designed Expressly for the Oil Pipeline industry by Forrest M. Towl, C.E. 1910 Made in U.S.A.
Front Scale: Capacity/hr [ AIE, SAE, Dia of Pipe (Inches), Length(Miles), Cd, Sum of Delivery Pressures ] Difference of Delivery Pressures
Back scale: [Length of Stroke, Explosions/min, H.P., Ratio of Compression ]
Archive - Scan by Rick Mandrell, his father Thomas C. Mandrell (1919-2002) used and collected these slide rules while working for Dow Chemical Co's pipeline department. .

BIBLIOGRAPHY OF THE SLIDE RULE (1620-1909) from
HISTORY OF THE LOGARITHMIC SLIDE RULE
by FLORIAN CAJORI
SCHOOL OF ENGINEERING, COLORADO COLLEGE,
Colorado Springs, Col. 1909


1620. Canon Triangulorum. Gunter (London)
1624. Description and Use of the Sector, Cross-Staff and Other Instruments. Gunter (London)
1624. L.usage de la règle de proportion en l.arithmétique et géométrie. Edmund Wingate (Paris)
1624. Construction, description et usage de la règle de proportion. E. Wingate (Paris)
1626. The Use of the Rule of Proportion. E. Wingate (London). Other editions, 1628, 1645, 1658, 1683
1626. Arithmétique logarithmique. E. Wingate
1626. Logocanon ou règle proportionnelle Henrion (Paris)
1630. Of Natural and Artificial Arithmetic. E Wingate (London)
1632. The Circles of Proportion and the Horizontal Instrument. William Forster. (London)
1633. The Circles of Proportion and the Horizontal Instrument with an Addition, etc., and an Appendix; The Declaration of the Two Rulers for Calculation
1672. The Description and Use of an Instrument called the Double Scale of Proportion. Seth Partridge (Written in 1657)
1677. Timber Measure by a Line of More Ease, Dispatch and Exactness than any other way now in use, by a Double Scale. Henry Coggeshall (London)
1682. A Treatise of Measuring by a Two-foot Rule, which slides to a Foot. Henry Coggeshall (London). (A Second edition of his 1677 book)
1690. Cursus Mathematicus. Leybourn
1696. Descriptio instrumenti Mathematici universalis, quo mediante omnes proportiones sine circino at que calculo methodo facillima inveniuntur. Biler.
1699. Pes mechanicus artificialis d. i. neu erfundener Maassstab, mi welchem alle Proportionen der ganzen Mathematik ohne mühsames Rechnen u. s. w. können gefunden werden. Michael Scheffelt (Ulm)
17.. Arithmétique linéaire. Pouchet
17.. Elémens du Pilotage. Pezenas
17.. Encyclopédia méthodique (mathématiques). Johann Bernoulli III (1744.1807)
17.. Encyclopédia Méthodique (marine), Article .Echelle anglaise.. Lalande
17.. Excise and Malt-Examiners. Assistant, Useful also for Supervisors and Officers. J. Vero (London)
17.. Mathematical Companion. Hunt
17.. Pratique du Pilotage. Pezenas
1707. The Young Mathematician.s Guide . . . , with an Appendix on Practical Gauging. John Ward (London)
1716. Lexicon Technicum. Harris
1722. The Art of Practical Measuring easily performed by a Two-foot Rule which slides to a Foot. Henry Coggeshall. (A third edition of his 1677 book; a fourth edition, revised by John Ham, was brought out in 1729, and a seventh edition in 1767)
1723. Construction and Principal Uses of Mathematical Instruments. M. Bion (Translated by E. Stone)
1726, 1743. New Mathematical Dictionary. E. Stone (London)
1727. Histoire de l.académie royale des sciences. Jean Baptiste Clairaut
1727. Theatrum Arithmetico-Geometricum. Jacob Leupold (Leipzig)
1733. The Description and Use of an Universal and Perpetual Mathematical Instrument. Benjamin Scott (London)
1740. Lives of the Professors of Gresham College. Ward
1740. Theory and Practice of Gauging. Robert Shirtcliffc (London)
1744. Mémoires de l.académie royale des sciences de l.année, 1741 (Paris)
1753. Dictionnaire universel de mathematique et de physique. Tome I, Saverien
1755. Royal Gauger. C. Leadbetter
1755. The Royal Gauger. Leadbetter. 4th Ed. (London)
1761. Beschreikung und Gebrauch der Logarithmischen Rechenstäbe. Johann H. Lambert (Augsburg). New edition published in 1772
1766. Abridge du Pilotage. Lemonnier (Paris)
1768. Nouveaux essays pour determiner les longitudes en mer par les movements de la lune et par une seule observatione. Pezenas (Paris)
1768. (Treatise on Slide Rule.no name). Flower (London)
1775. Treatise on Mathematical Instruments. John Robertson
1778. Atlas céleste de Flamsteed, translated by Fortin
1777. Lambert.s Briefwechsel, Vol. IV., p. 379
1778. A Description of the Lines drawn on Gunter.s Scale, as improved by Mr. John Robertson. William Mountaine (London)
1782. Isaaci Newtoni Opera, Tom. IV. Edit. S. Horsley (London)
1787. Philosophical Transactions. William Nicholson (London). Pt. II, pp. 246.252
1788. Arithmetic. Nicholas Pike
1792. A Complete Treatise on Practical Mathematics. John Macgregor (Edinburgh)
1794. Arithmetic. George Fisher (Mrs. Slack) (London)
1797. Nicholson.s Journal, Vol. I., p. 375
1798. De la résolution des equations numériques de tous les degrés Lagrange (Paris)
1799. Cadrans logarithmiques adaptés aux poids et mésures. A. S. Leblond (Paris)
1799. Instructions sur l.Usage des Cadrans logarithmiques. François Gattey (Paris)
18.. Dictionary of Authors. Art. .Wingate, Edmund. S
18.. Dictionary of National Biography. Sidney Lee
18.. Dingler.s .Polytechnic Journal.. (Berlin) .Many references
18.. Dyck.s .Katalog Nachtrag.
18.. English Cyclopaedia (Arts and Sciences)
18.. Instructions for the use of A. W. Faber.s Improved Calculating Rule. C. N. Pickworth 72
18.. Mem. dell. Accad. d. Scie. di Torino, T. XXV, Serie II
18.; Philosophical and Mathematical Dictionary. Hutton
18.. .Philosophical Magazine,. Vol. 45, p. 387 (London)
18.. Theorie du logarithmischen Rechenschieber. Franz Ruth
1800. Dizionario enciclopedico delle matematische delli signori. Art. .Logaritmiche. (Padova)
1802. .Mechanics. Magazine,. Vol. 5 (London)
1802. Navigator. Bowditch
1802. Nicholson.s Journal, Vol. 1, p. 452
1803. De Ingenieur
1805. .Schoolmaster.s Assistant,. by Thos. Dilworth, brought out in Philadelphia by Robert Patterson
1808. Mathematisches Wörterbuch, I. Abtheilung, 3. Theil (Leipzig)
1810. Explication et usage de l.arithmographe. Gattey (Paris)
1811. Mathematical Tables. Hutton
1813. Complete Measurer. Hawney (1st Edit. London, 1717) (Baltimore)
1813. Complete Measurer. Hawney (Baltimore) . (The first edition of this book appeared in London in 1717)
1814. Dictionary of Pure and Mixed Mathematics. Peter Barlow (London)
1815. Mathematical Dictionary. Charles Hutton
1815. .Journal des Mines,. Vol. 37, p. 101
1815. .Philosophical Transactions,. Part I (London)
1817. .Nicholson.s Journal,. Vol. 49, p. 187
1817. .Philosophical Magazine,. Vol. 49, p. 187 (London)
1820. (Treatise on Slide Rule.title not given) . Collardean (Paris)
1823. Dictionary of Mathematical and Physical Sciences. James Mitchell (London)
1823. Quarterly Journal of Science, Literature and Arts, Vol. XVI, p. 357 (London)
1827. Treatise on the Steam Engine. John Farey (London)
1827. (Treatise on Slide-Rule.no title given). J. F. Artur (2e éd., 1845) (London)
1829. Gill.s Technological Repository, Vol. IV, p. 33 (London)
1831. .Mechanics. Magazine. (London)
1832. Brewster.s Edinburgh Encyclopaedia, 1st Am. Ed. (Philadelphia)
1837. Instruction sur la manière de se servir de la règle à calcul. Mouzin. 3e éd. (Paris)
1837. (Treatise on Slide Rule.no title given). 35 éd. Ph. Mouzin (Paris)
1840. .Annales des Ponts et Chaussées.
1840. .Mechanics. Magazine,. Vol. 32, pp. 101, 102 (London)
1841. Mathematical Dictionary. Montferrier
1841. .Mechanics. Magazine
1842. Penny Cyclopaedia. (Article on .Slide Rule. by De Morgan)
1843. Anweisung zum Gebrauche des englischen Rechenschiebers. L. C. Schulz von Strasnitzki (Wien)
1844. On Coggeshall.s Sliding Rule (London)
1845. Palmer.s Pocket Scale, with Rules for its use in solving Arithmetical and Geometrical Problems (Boston)
1845. (Treatise on Slide Rule.no title given). Aug. Hadéry (Paris)
1845. On Bradford.s Sliding Rule (London)
1846. Improvement to Palmer.s Endless Self-Computing Scale and Key; . . . John G. Fuller (New York)
1847. Arithmetical Books from the Invention of Printing to the Present Time. De Morgan (London)
1850. La Tachéométrie. J. Parro (Turin)
1851. A Treatise on Slide Rule. L. Lalanne (London)
1851. Instruction sur les règles à calcul. Lalanne
1851. Règle à calculs modifieé. Mannheim (Metz)
1851. Auleitung z. Gebrauche einiger logarith. getheilter Rechenschieber (Wien)
1852. Gebrauchs-Anweisung fur Rechenstäbe (Paris)
1852. Instruction sobre das reglas de calculo. (Paris)
1853. Règle à Calcul expliquée. M. P. M. N. Benoit (Paris)
1853. Bulletin de la sociéte d.encouragement pour l.industrie nationale
1853. (Treatise on Slide Rule-no title given). P. M. N. Benoit (Paris)
1853. Nouvelles Annales de Mathématiques, 1ére série, Tome XII, pp. 113.116
1854. Nouvelles Annales de Mathématiques, Tome XIII,p.36
1854. Mittheilungen des Gewerbevereins f. d. Königreich Hannover, p. 169
1856. Ueber Visir- und Recheninstrumente. Ernest Sedlaczek (Wein)
1856. Mechanics. and Engineers. Book of Reference and Engineers. Field Book. Charles Haslett and Chas. W. Hackley (New York)
1857. Par. Comptes rendus de 1. Acad. d. Sci. 44, p. 22.
1859. Teorica e practica del regolo calcolatore Quentino Sella (Torino)
1860. Encyclopaedia Britannica. (Eighth Ed.)
1860. Atti dell. Imp. Reg. Istituto veneto di scienze (Venice)
1861. Handbook of the Slide Rule. W. H. Bayley (London)
1863. Bull. de la sociéte d.encouragement pour l.industrie nationale (Paris)
1864. .Zeitschr. des Architecten- u. Ingenieur-Vereins f. d. Königp.. Hannover, Vol. 10, p. 454
1865. (Treatise on Slide Rule.no title given). Fr. René (Paris)
1866. Report British Assn. (London)
1867. Giornale di Matem. del Prof. Battaglini (Naples).
1868. Appleton.s Dictionary of . . . Engineering, Vol. I (New York)
1868. Instruments et machines calculer (Paris)
1869. (Treatise on Slide Rule.no title given. Translation of Q. Sella.s book.1859). Montefiore Lévi (Paris)
1871. Drawing and Measuring Instruments. J. F. Heather (London)
1871. Torino Aec. Sci. Memorie
1872. (Treatise on Slide Rule.no title given). Labosne (Paris)
1872. Der Topographische Distanzmesser mit Rechenschieber. J. Stambach (Aaran)
1872. Auleitung zum Gebrauche des Rechenkreises. R. Weber
1872. Auleitung zum Gebrauch der Rechenscheibe. F. M. Clouth (Hamburg)
1874. .Annales du Gènie Civil. (Paris)
1874. .Deutsche Bauzeitung,. Bd. 8, p. 136
1874. A Treatise on Mathematical Instruments J. F. Heather (London)
1875. Die Grahpische Statik. (Zurich)
1875. Treatise on Slide Rule.no title given). Claudel(Paris)
1875. Proceed. London Math. Soc., Vol.6, p. 113 (London)
1876. Notice sur les travaux et titres scientifiques. M. Léon Lelanne
1877. Geschichte der Astronomie. R. Wolfe (München)
1877. Catalogue of Instruments manufactured by W. F. Stanley (London)
1877. Das . Stereometer, Körper-Messinstrument (Budapest)
1877. Notes pratiques pour études de tracés. I. Moinot (Paris)
1877. .Zeitschr. des Vereins Deutscher Ingenieure
1878. Méthodes graphiques pour l.expression des lois empiriques, etc
1878. Veneto Istituto Atti. A. Favaro. . Numerous references
1878. .La Nature. (Paris)
1878. Spiral Slide Rule. George Fuller (London)
1879. Statique Graphique. Favaro-Terrier. (Paris)
1880. Proc. Engineers. Society of Western Penna
1881. Knight.s American Mechanical Dictionary, Vol. II
1881. The Slide Rule Simplified. Robert Riddell (Phildelphia)
1881. .Zeitschr f. Vermessungsw.
1881. Dingler.s .Polytechnisches Journal. (Augsburg)
1883. (Booklet on Slide Rule.no title given). Prof. Cherepashinskii (Moscow)
1885. Leçons de statique graphique, 2ième partie, calcul graphique. A. Favaro, Translated into French by P. Terrier (Paris)
1885. (Treatise on Slide Rule.no title given). F. Guy, 3e éd. (Paris)
1885. (Treatise on Slide Rule.no title given). Gros de Perrodil (Paris)
1885. Van Nostrand.s .Engineering Magazine.
1886. Regolo Calcolatore. Quintino Sella. 2 ed. Ital. (Torino)
1886. Dingler.s .Polytechnisches Journal.
1886. Gewerbeblatt aus Würtemberg
1886-7. Transactions of Am. Soc. M. E., Vol. VIII, pp. 707.709
1888. .Centralblatt Bauverwaltung.
1888. .Railroad Gazette.. (New York)72
1889. A New and General Biographical Dictionary. Art. by Oughtred, quoted in .Nature,. Vol. 40, p. 458
1889. Portefeuille des Conducteure des Ponts et Chaussées (Paris)
1889-90. .Techaiker,. Vol. 12, p. 34
1890. The Slide Rule and How to Use it. Charles Hoare (London)
1890. Instruction pour la determination de la distance et de la différence d.altitude d.un objet à un point de Station. J. Stambach (Aarau)
1890. Dingler.s .Polytechnisches Journal.
1891. .Zeitschr. f. Vermessungsw..
1891. .Engineering News. 81
1891. The Mannheim Slide Rule. W. M. Cox (New York)
1891. Explanation of the Principle and Operation of the Mannheim Slide Rule. C. W. Crockett (Troy, N.Y.)
1892. International Cyclopædia. (New York) iv
1892. .Engineering and Mining Journal. (NewYork), Vol. 54, p. 130
1892-4. .Zeitschr. fur Vermessungsw.
1893. Scherer.s Logarithmischgraphische Rechentafel (Kassel)
1894. .Schweizer. Bauzeitung,. Vol. 23
1894. .Engineering News,. Vol. 32, p. 103
1894. Der Praktische Maschinen-Constructeur, Vol. 27,p.8
1894. .Engineering Record,. Vol. 30, p. 31
1895. .Nature.. (London)
1896. .Engineering,. Aug. 7p 172 (London)
1896. Engin. Ass.n of the South, Vol. 7 (Nashville, Tenn.) pp. 92-99
1897. Handbuch der Vermessungskunde. W. Jordan, Bd. II, p. 134 (Stuttgart)
1897. .Engineering News,. Vol. 38, p. 291
1897. .Mechaniker,. Vol. 5
1898. Règle à calcul, modèle spécial. A. Beghin (2e éd., 1902, Paris)
1898. .Yale Scientific Review,. Vol. 5, p. 47
1898. Logarithmicon. E. Nash, p. 43 (Dublin)
1898-1904. Encyklopädie d. Math. Wiss, (Leipzig)
1899. Zur Theorie des Rechenschiebers. (Berlin)
1899. Traité de Momographie. M. d.Ocagne (Paris), p. 361
1899. .Zeitschr. f. Vermessungsw.,. Vol. 28, p. 660
1899. The Use of the Slide Rule. F. A. Halsey, p. 74 (New York)
19.. Instructions for the Use of A. W. Faber.s Improved Calculating Rule. C. N. Pickworth (London)
19.. Instructions for the Calculating Slide Rule. Albert Nestler, p. 63 (Lahr, Baden)
19.. Slide Rule Instructor for Instruction on Chad-wick.s Improved Slide Rule. John Chadwick (London)
19... Some Quick and Easy Methods of Calculating. R. G. Blame (London).
19.. The Runnerless Slide Rule. F. F. Nickel
19.. Treatise on a Box of Instruments. T. Kentish (Philadelphia).
19.. Engineers. Slide Rule. W. Tonkes (New York) ...
1900. .Zeitschr. f. Vermessungsw.,. Vol. 29, p. 233
1900. .Zeitschr. f. Instrumentenkunde,. Vol. 20, p. 336
1900. .Comptes rendus,. Vol. 131, p. 1289
1900. .Engineering News,. Vol. 43, p. 232
1901. Le Système Métriques des Poids et Mesures. G. Bigourdan (Paris)
1901. Oesterreich. Woch. ensch. f. d. offentl. Baudienst, Vol. 7, p. 72
1901. .American Machinist,. Vol. 24, p. 339 (New York)
1901. .Journal de Physique,. Sept
1901. .Nature,. Vol. 64, p. 523
1901. Rechentafel System Proell (Berlin)
1901. Slide Rule Notes. Lt.-Col. H. C. Dunlop, R.F.A. and C. S. Jackson, M. A. (London)
1901-1903. .Engineering News. (New York)
1902. (Treatise on Slide Rule.no title given). Leclair (Paris) 58
1902. .Journal de l.Ecole Polytechnique. IIe sérié, septième cahier (Paris, p. 223)
1902. The Slide Rule. E. M. Scofield (Chicago)
1902. .American Machinist,. Vol. 25, p. 1515
1902. .Rechenblätter. (Berlin)
1902. .Technological Quarterly,. Vol. XV, pp. 250-259 (Boston)
1902. .Nature,. Vol. 67, p. 141
1902. .Verhandl. d. Vereins z. Beförderung d. Gewerbefleisses. (Berlin), Vol. 21, p. 48
1903. (Treatise on Slide Rule.no title given). Jully (Paris)
1903. Treatise on Slide Rule.no title given). Dryssé (Paris)
1903. Règle à calcul Mannheim (Paris)
1903. .Zeitschr. f. Mathematik. u. Physik.. Vol. 48, p. 134
1903. .De Ingenierer,. Vol. 18, p. 94
1903. .Engineering Record. (New York)
1903. Calculating Scale; a Substitute for the Slide Rule. W. Knowles (New York)
1903. Some Quick and Easy Methods of Calculating. R. G. Blame (London)
1903. Thacher.s Patent Calculating Instrument. Edwin Thacher (New York)
1904. .Engineer,. April 7, p. 346 (London)
1904. .Mathematical Gazette,. Vol. II, p. 337 (London)
1904. .American Machinist,. Vol. 27, Pt. II, p. 1376 (New York)
1904. .Nature,. Vol. 69, p. 485
1904. .American Machinist. (New York)
1904. .Comptes rendus,. Vol. 138, pp. 1266.1268 (Paris)
1904. Slide Rule. E. M. Scofield (New York).
1905. Calcul simplifié. Maurice d.Ocagne, 2e éd. (Paris)
1905. .Engineering News.
1905. Mannheim and Multiplex Slide Rules. L. W. Rosenthal (Chicago)
1905. .Schweizerische Bauzeit,. Vol. 45 (Zurich)
1905. .Zeitschr. f. Instrumentenkunde,. Vol. 25, p. 385 (Berlin)
1905. .Engineering News,. Vol. 54, p. 487
1906. .American Machinist,. Vol. 29, Pt. II, p. 256 (New York)
1906. The Slide Rule: a Practical Manual. C. N. Pickworth (London)
1906. Catalogue of Keuffel & Esser Co. (New York)
1906. Drawing Instruments. W. H. Harling (London)
1906. Mathematical Drawing and Surveying Instruments. W. H. Harling (London)
1906. .American Machinist.
1906. .Electric Journal,. Vol. 3, pp. 116.118 (Pittsburg, Pa.)
1907. Règle à calculs. P. Rozé, pp. 2, 3, 29.58 (Paris)
1907. Theorie et usage de la règle à calculs. P. Rozé (Paris)
1907. .Electrical World,. Vol. 50, p. 402 (New York)
1907. .American Machinist,. Vol. 30, Pt. II, p. 76
1907. Slide Rule Manual. John L. Hall (New York)
1907. Catalogue of Drawing Materials. Kolesch & Co. . (New York)
1907. Complete Mechanical Slide Rule and How to Use it. F. T. Hodgson (New York) .
1908. Der logarithmische Rechenschieber. E. Hammer. 4te Aufl. (Stuttgart)
1908. Rendiconti del Circolo Matematico di Palermo, Tomo 26, pp. 1.63
1908. Der logarithmische Rechenschieber. E. Hammer (Stuttgart)
1908. .Zeitschr. f. Mathem. u. Naturwissensch.. (Unterricht)
1908. .Nature,. Vol. 77, p. 500
1908. .American Architect,. Feb. 12
1908. .American Machinist,. Vol. 31, p. 613
1908. .Engineering Record,. Vol. 58
1908. How to Use Slide Rules. D. Petrie Palmedo (New York) .
1908. Mannheim and Multiplex Slide Rules. LW. Rosenthal (New York) .
1908. Slide Rule Calculator.
1909. Catalogue of Keuffel & Esser Co. (New York)
1909. .Colorado College Publication,. Vol. I, No. 6.
1909. .Electrical Review and Western Electrician,. Vol. 54, p. 399
1909. .Elektrotechnischer Anzeiger.
1909. .Engineering News,. Vol. 61, p. 266
1909. Ein Rechenschieber mit Teilung in gleiche Intervalle auf der Grundlaged er zahlentheoretischen Indizes. Fur den Unterricht Konstruiert (München)
1909. .Zeitschr. f. Math. u. Naturwiss.. Unterricht, Vol. 40, p. 59
1909. History of the Slide Rule. F. Cajori (New York)
1909. .Engineering News,. Vol. 62, p. 40
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