Benjamin Franklin's phonetic alphabet as follows: Franklin's proposed alphabet included seven letters to represent vowels. This set consisted of two new letters, in addition to five letters from the existing English alphabet: a, e, i, o, u. The first new letter was a formed as a ligature of the letters o and a, and used to represent the sound (as written in IPA). The second, ɥ, was used for . Franklin proposed the use of doubled letters to represent what he called long vowels, represented by modern phonemes thus: as the long-vowel variant for (or, in his notation, "cɩcɩ" versus "cɩ"), for ("ee" versus
Phonological history of English low back vowels Phonological history of English low back vowels The phonology of the low back vowels of the English language has undergone changes both overall and with regional variations, through Old and Middle English to the present. The sounds heard in modern English were significantly influenced by the Great Vowel Shift, as well as more recent developments such as the "cot–caught" merger. In the Old English vowel system, the vowels in the low back area were unrounded: . There were also rounded back vowels of mid-height: . The corresponding spellings were and , with the length distinctions not normally marked; in modern