Large map with full information on Telsur subjects
Map 4 is based on the impressionistic analysis of the Telsur interviews with 603 subjects, focusing on that part of the interview that elicits the pronunciation and minimal pair judgments of hill and heel. As in all the studies of mergers in this and preceding maps, this elicits information on production and perception: whether the two words are pronounced and/or judged to be distinct, the same, or somewhere in the middle.
Because the progress of the merger is more limited than the mergers presented in Maps 1-3, the focus here is primarily on the speakers who show the merger. Data is obtained from almost every speaker: the small black dots indicate people who clearly make a difference between /il/ and /iyl/.
The red circles are the speakers who are completely merged, in both production and perception. The heavest concentration is found in the Southern States. 22 of the 35 subjects who show complete merger are in the Southern States, concentrated in two main areas: central and western North Carolina, centering around the Research Triangle of Raleigh and Durham, and in central and West Texas. Throughout the West and the North Midlandthere are scattered examples, but no geographic concentration. The partial evidence for merger illustrated by the orange, magenta and yellow circles show roughly the same distribution. The North, Eastern New England, mid-Atlantic States and Florida are free of any sign of the merger.
The relative numbers of the orange and magenta circles show one of the constant principles of the mechanism of merger: it takes place in perception before production. Of the asymmetric cases, 14 show merger in perception, and only 4 in production. At the same time, it is interesting to note that there are no orange circles in the Southern States, suggesting that the mechanism of merger in the West is somewhat different from that in the South. This is in fact the case
. In the West and in Texas, the merger of heel and hill. feel and fill , generally takes place with a lax vowel in both word types. In the Southern States, the merger is a reflection of that stage of the Southern Shift that raises and fronts the nuclei of the short front vowels /i/, /e/ and /æ/. Before /l/, the nucleus of /i/ is a high front vowel. The nucleus of /iy/ does not centralize and lower as it does in other environments, but remains in high front position and merges with /i/. The acoustic studies to follow will illustrate this difference in detail.
For the parallel merger of the high back vowels before /l/, see Map 5.