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In page Helen Wallis:

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In 1951, she was appointed assistant to R.A. Skelton, superintendent of the Map Room at the British Museum, succeeding him in 1967.[citation needed] She was the first woman to hold the post. In 1968 she was responsible for the acquisition of the map collection of the Royal United Services Institution. She also discovered the earliest version of England's first globe, by Emery Molyneux and thought to date from 1592, at Petworth House.[citation needed]