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The AtoZ of Slide Rules This is a fairly general AtoZ of slide rules. It is designed for people who have never used a slide rule before or who have used one in the past but largely forgotten what to do. The sections are arranged in alphabetical order. If you are a complete novice then I suggest that you go first to the "Beginners Start Here" section and then work through the individual sections of the AtoZ. After that you can tackle the book "Teach Yourself the Slide Rule" or read some of the online instruction manuals. Whilst this AtoZ tries to cover a wide range of scales, it is impossible to cover all possible types of scales or all types of rules. If you have a scale that you cannot identify then have a look at some of the sites mentioned on the resources page. If you cannot find what you want there there, post a question on the slide rule forum (http://www.egroups.com/messages/sliderule) where someone will, almost certainly, be able to be able to help you. (A word of warning  some of the participants have a rather unusual sense of humour!). The descriptions below are of two main types: descriptions of general purpose scales which you will find on many rules and descriptions of rules for special functions. In the latter case I consider how typical calculations can be performed using a range of special purpose slide rules but only consider any special scales or gauge marks. The aim is to cover enough rules so that if the actual rule you have is not included a similar one will be, which will enable you work out how to use it. (For me part of the fun of slide rule collecting is working out how to use new rules.) Much of my effort over the coming months will be to add more information on these special rules some of which is at present covered by special purpose rules in my collection. The sections are identified by the yellow background. 

Contents 
Notes 
Accuracy  How to check the accuracy of your rule. 
Addiator  A device for addition/subtraction sometimes found on the back of slide rules. 
Basics  
Business rules  See Commercial rules 
Circular slide rules (see Concise)  
Coggeshal rules  See timber rules 
Commercial rules  Six rules used as examples 
Concise 28  A common circular rule. 
Cubes and cube roots  Uses of K scales 
Cursor (indicator)  Covers use of multiline cursors 
Cylindrical slide rules (see Otis King)  
Darmstadt (see standard scale configurations)  
Decimal point  How to fix the position of the decimal point. 
Division (see Multiplication and Division)  
EasrR sewer flow rule  A hydraulic rule for sewer flow. 
Electrical  Faber Castell, Thornton PIC, W&G and Graphoplex rules are used as examples. 
Electronic  Graphoplex and Pickett rules are used as examples. 
Exponentiation  The use of loglog scales 
Financial rules  See commercial rules 
Fowler  A well known circular rule 
Gauge points  Explains the use of the p and other symbols. 
Gauging  Calculating the volume of casks when full or partly full. 
History  A very brief history of slide rules 
Hydraulics (See EasyR, Tarrant and Mears)  
Hyperbolic functions  Pickett and Keuffel & Esser rules are used as examples. 
Indicator  See cursor 
Logarithms (background)  
Logarithms (base 10)  
Mannheim (see standard scale configurations)  
Mears hydraulics rule  A circular rule for pipe and channel flow. 
Multiplication and Division  Shows use of C, D, CI, CF and DF scales. 
Nonlinear rules  
Otis King  A well known cylindrical rule. 
Pocket watch slide rules (see Fowler)  
Pythagorean  
Raising to a power (see exponentiation)  
Reading the scales  How to read the scale graduations. 
Roots and powers  squares and square roots  Basic use of A and B scales 
Roots and powers  cubes and cube roots  Basic use of K scale 
Roots and powers  calculation involving  Multiplication and division of numbers involving squares and square roots. 
Rietz (see standard scale configurations)  
Scales  How to identify the scales on a rule and how to read them. 
Sin(e) (see trigonometric calculations)  
Slide  
Squares and square roots  The use of the A and B scales. 
Standard scale configurations  
Stator  See stock 
Stock (stator)  
Tan(gent) (see trigonometric calculations)  
Tarrant hydraulics slide rule.  For pipes and channels. 
Timber rules  Instructions on a common early type of rule. 
Trigonometric calculations : scales on stock (stator)  Found on many rules from the USA. 
Trigonometric calculations : scales on front of slide  Found on many rules from Europe. 
Trigonometric calculations : scales on back of slide  Found on many early rules from all over the world. 
Trigonometric calculations : scales on Thornton/P.I.C. rules  Patented and only found on rules from this maker. 
Trigonometric scales  comparison  Comparison of different methods of presenting scales. 
Trigonometric calculations  gauge points for small angles  Common on European rules 
Ullaging (see gauging) 