The northern limit of the Provençal language formed a line starting from the Pointe de Grave at the mouth of the Gironde, passing through Lesparre, Bordeaux, Libourne, Périgueux, rising northward to Nontron, la Rochefoucauld, Confolens, Bellac, then turning eastward to Guéret and Montluçon; it then went south-east to Clermont-Ferrand, Boën, Saint Georges, Saint Sauveur near Annonay. The Dauphiné above Grenoble, most of the Franche-Comté, French Switzerland and Savoy, are regarded as a separate linguistic group known as Franco-Provençal, for the reason that the dialects of that district display characteristics common to both French and Provençal.[1] On the south-west, Catalonia, Valencia and the Balearic Isles must also be included in the Provençal region. As concerns the Northern limit, it must not be regarded as a definite line of demarcation between the langue d'oil or the Northern French dialects and the langue d'oc or Provençal. The boundary is, of course, determined by noting the points at which certain linguistic features peculiar to Provençal cease and are replaced by the characteristics of Northern [3] French. Such a characteristic, for instance, is the Latin tonic _a_ before a single consonant, and not preceded by a palatal consonant, which remains in Provençal but becomes _e_ in French; Latin cant_a_re becomes chant_a_r in Provençal but chant_e_r in French. But north and south of the boundary thus determined there was, in the absence of any great mountain range or definite geographical line of demarcation, an indeterminate zone, in which one dialect probably shaded off by easy gradations into the other.