Blundell Rules Ltd started making slide rules in about 1947 in Luton. UK In 1956 they moved to Weymouth. They merged with W H Harling of London, who were established drawing instrument makers, to form Blundell Harling Ltd, and moved the Harling business to Weymouth in 1964.
Blundell Rules Ltd Academy 300 open frame simplex 10” plastic slide rule. It has a blue/clear vinyl case and instruction leaflet B19. Scales are: K,A{B,C1,C}D,L.
Harling Academy series slide rule, instructions and case. Condition is "Used". Dispatched with Royal Mail 2nd Class.