This non-commercial website was a 60th birthday present from Ros. The name stems from another family member - our daughter Siân. As a teenager she often told her friends: “My Dad? Oh, he collects expensive sticks of wood!”
When the latest PC/tablet is out-of-date in 6 months it may come as a surprise that the Englishman in the image, the Rev. William Oughtred (1575-1660), invented a calculator around 1621 that would be in continual daily use for nigh on the next 400 years. My hobby is collecting and writing about this analogue calculating wonder - the SLIDE RULE.
This site is a virtual “display cabinet” for my collection (as it gets uploaded) of
slide rules and the odd mechanical calculating aid plus a “bookshelf” for my published articles - enjoy browsing.
Anyone needing a “memory jogger” or is just intrigued how such analogue calculators of the past worked, the International Slide Rule Museum has a richly illustrated “How To Use The Slide Rule” teach yourself course. Afterwards try doing a few trial calculations with Derek Ross’ online simulation of a Pickett N909-ES slide rule. If all this gets you thinking about starting your own collection then the UKSRC/Oughtred Society’s ”Beginner’s Guide to Collecting Slide Rules” can be a great help.
For any educators looking for maths related inspiration & teaching aids/material then you need to look no further than Nicola Marras’ website. If you are just looking for reference books on slide rules try one of these: MyList 1 or MyList 2 .
This German maker made quality slide rules. They produced 300 different rectilinear wood and plastic models in 10 different stock lengths ranging from 10 to 100cm. They also made drum and specially commissioned circular models. Check out my Nestler’s here ...
Generically a slide rule can solve complex calculations but CANNOT do simple arithmetic. A rare and unusual exception is the newest addition to the collection - a System Korte slide rule that CAN add and subtract!
The world of collecting has lost two world renowned experts & compilers of two of the most legendary collections. American collector Bob Otnes (1932-2019) passed away in April and in May Swiss collector Heinz Joss (1929-2019) passed away. They will both be sorely missed.
Ace Hoffman has developed an awesome simulation of a linear, round, concentric and drum slide rule. From Ace’s Homepage download a function-rich version for your phone, tablet or desktop.
In memory of long-scale expert Ed Chamberlain (†18-10-2017) fellow collector Otto van Poelje has reissued as a free download his out of print private 2013 publication: “LONG-SCALE SLIDE RULES in LIFE-SIZE IMAGES”
Lawrence made the only known slide rule considered so vital to the WWII effort that the UK & US governments had it classified - based on research from MIT it calculated radar antenna beam patterns, beam width, gain, etc.
|A.W. Faber-Castell||4/92, 8/13, 8/14, 8/15 & 8/168|
|ALRO||Cobol Analyser, HaTex & Truck Tyres|
|Ausschuss fuer Wirtschaftliche Fertigung (AWF)||SR703, SR705-709, & SR754|
|Controller Calculator KG||200 R|
|DARGUE Bros. Ltd / Simplon||Sub-Ivory SR-1 & SR-4 + Honduras SD10, WR-2A, WR-5 & WR-7|
|Engineering Instruments Inc.||Either circular “vinylite” model|
|Fearns Calculators||Barber Shop Harmony Calculator|
|Fowler||Nautical, Artillery, Kearns & Mackay|
|Graphoplex||6245 & 6250|
|Inglis||FLASH: Pricing, Photographic Exposure, Stock Exchange, Foreign Money, Paper Trades & Health Insurance|
|L&C Hardtmuth / Classic||10" Series III|
|Lawrence Engineering Services||S-M (C.V. Ore) & Exposure (MIT)|
|Nestler||Cursor/runner for 24b (100cm), RP 75, Kreisrechner & Disc-O-Lator|
|Slide Rule & Scale Engineering Co. (S.E.&S.E.)||- any -|
|Unique||Norman, Perfectus, Dial & Junior|