The map opposite shows that, in the south west of the Gaelic speaking area, 'deug' (teen) is pronounced with a long E, something like 'jeh-k'. In other areas, to varying extents, this long vowel has been broken to be pronounced approximating to 'jeeuk'.  This feature is found in most Gaelic words which have a long E, a vowel found in Irish Gaelic and representing an earlier form of the sound.  It was investigated by the Gaelic scholar, the late Kenneth Jackson (ref 2), who selected eight Gaelic words and investigated the extent to which they had been broken. His conclusion was that there appears to have been a central innovative area, mainly in Ross-shire, where most of the long E words have been broken. Around this area, the breaking becomes progressively less in evidence the futher away from the central area one moves.   The maps opposite illustrate three of the words chosen by Jackson, viz., 'deug' (teen), 'feur' (grass) and 'Seumas' (James).  It can be seen that while 'deug' is unbroken only in Kintyre and the neighbouring islands, 'feur' (grass) is found in a sweeping zone round the perimenter of the Gaelic speaking world (as it was in the mid 20th century!), stretching eastwards from Argyll through Perthshire, Speyside and on to Sutherland (east and north coasts and the west coast to near Kinlochbervie).  There is a gap in the sweep near Inverness, where the breaking influence may have proceeded north-eastwards along the Great Glen.

In the case of 'Seumas' (James), the conservative use of long E is well preserved, being used everywhere in its unbroken form, as the map shows, apart from in Ross-shire and some adjacent parts of western Sutherland.

The 'deug' and 'feur' maps show what may be an intermediate form of breaking, taking the form of the long vowel 'i', followed by 'a'. This can be seen stretching northwards from Kintyre into the Great Glen, with branches to Speyside and westwards towards Skye. This feature does not appear with 'Seumas'.

It is of interest to note that this partial breaking is also shown, for both 'feur' and 'deug' at the northern and southern ends of the Uist-Barra island chain, perhaps a result of relative isolation from the main area of innovation.