The Survey of English Dialects was undertaken between 1950 and 1961 under the direction of Professor Harold Orton of the English department of the University of Leeds. It aimed to collect the full range of speech in England and Wales before local differences were to disappear. Standardisation of the English language was expected with the post-war increase in social mobility and the spread of the mass media. The project originated in discussions between Professor Orton and Professor Eugen Dieth of the University of Zurich about the desirability of producing a linguistic atlas of England in 1946, and a questionnaire containing 1,300 questions was devised between 1947 and 1952.