Boston accent
On the other hand, the Boston accent merges the "short "o"" with the "aw" phoneme: the two classes exemplified by "caught" and "cot" thus both become an often long and rounded , so that "caught", "cot", "law", "wand", "rock", "talk", "doll", and "wall" all are pronounced with the same vowel. By contrast, New York accents and southern New England accents have for "caught" and for "cot" and the London accents have and , respectively. In Boston and some other parts of New England, a few words ending in , e.g., "hot" and "got", can be pronounced with an entirely different phoneme, however, sounding instead like "hut" and "gut", respectively.
Received Pronunciation
Like all accents, RP has changed with time. For example, sound recordings and films from the first half of the 20th century demonstrate that it was usual for speakers of RP to pronounce the sound, as in "land", with a vowel close to , so that "land" would sound similar to a present-day pronunciation of "lend". RP is sometimes known as the Queen's English, but recordings show that even Queen Elizabeth II has changed her pronunciation over the past 50 years, no longer using an -like vowel in words like "land". 
Some changes in RP during the 20th century include:The change in RP may be observed in the home of "BBC English". The BBC accent of the 1950s is distinctly different from today's: a news report from the 1950s is recognisable as such, and a mock-1950s BBC voice is used for comic effect in programmes wishing to satirise 1950s social attitudes such as the Harry Enfield Show and its "Mr. Cholmondley-Warner" sketches.