Routledge Rule by Bradburn

Following on from the Coggeshall design and in parallel with later versions came a number of further designs all utilising the Carpenter's rule as the vehicle for carrying the calculating elements of a number of 'Engineering' and 'Other' slide rule designs.
Chronologically we have Joshua Routledge as the creator of this Engineering standard.
Here a 1-10-100 scale is used for A, B, and C and a 1-10 D scale as per Boulton and Watt's original Soho Engineering design.