Site Information

This archive is based on the work undertaken by Ed Chamberlain over many years with significant additions and reorganisation by David Rance.

What are long scale rules?

Tick marks and magnifying cursors are well-known visual aids to precision. Leaving aside the manufacturing process, calculating accuracy is primarily proportional to the length of the scales used for multiplying and dividing. 'Long scales' are an alternative to just stretching out a scale for more accuracy. Such innovative single cycle long-scale designs offer more precision than comparable scales of the same physical length.

The archive is organised into the classification shown in the eleven table headings given below:

Table I Long Scale Linear Slide Rules without multiple sections
Ed Chamberlain: 1938 - 2017
Table II Long Scale Linear Slide Rules with multiple sections
Table IIILong Scale Devices with Gunter Lines, Gridirons and Graphical Charts & Tables
Table IV Long Scale Slide Linear Rules with sawtooth shaped scales
Table V Long Scale Circular Slide Rules
Table VI Long Scale Circular Slide Rules with concentric windings
Table VIILong Scale Circular Slide Rules with spiral windings
Table VIII Long Scale Circular Slide Rules with helical windings
Table IX Long Scale Cylindrical Slide Rules with linear windings
Table X Long Scale Rim, Band or Tape Slide Rules
Table XI World Record Slide Rules

The whole site may be viewed by clicking "Complete Archive", alternatively searching for specific items may be undertaken using "Search".

Currently this archive lacks photographs of the many rules itemised here.
Rod Lovett ( would be delighted to receive pictures or locations of pictures suitable for this archive.

Clicking on the "Background" tab at the top displays important related articles by David Rance, Jose Fernandez and Ed Chamberlain.

A Help File is provided whose primary aim is to discuss the use of the Search facility.

Created by Rod Lovett.