‘Douglas’ Combined Protractor and Parallel Rule (c.1942). It is made in frosted plastic.
Instructions (original) for use are pasted on the cardboard case. The protractor was designed by Rear Admiral H P Douglas RN. It was used by the donor (Mr AW Turner) in an engineering drawing office.
Used for measuring angles and bearings. Although manufactured for use by navigators at sea the item was used for plotting land surveys.
The cardboard case with the original donation by Mr AW Turner was badly marked with black ink rendering the instructions for use unreadable. In September 2021 Professor Paxton donated a similar item with a clean cardbord case which has been used to replace the original.