J Halden & Co Manchester London Vintage Wood Engineers Rule Ruler Engine Divided

Vintage Boxwood Armstrong Ruler- Imperial & Metric For Architects, Engineers etc

Blundell Harling No 451 BS 1347 RIBA Conversion Scale B Ruler + Scania Vintage

UNUSUAL VINTAGE SMALL WOODEN SLIDE-RULE ADVERTISING AN AMERICAN ENGINEERING CO.

Vintage A W Faber & Castell 2722 60's Scale Rule Engineer Math Tools Measurement

Blundell Harling Verulam Scale Rule Architect No. 3 Metric 300mm RIBA Approved

Small 6" Vintage White Rule Forman of Nottingham Nice Item Engineers Scale

Vintage Eastwoods Humber Cement 6" Concrete Slide/Scale Ruler Rule Straight Edge