32 SANSKRIT AND INDO-EUROPEAN the period of the Indo-Aryan invasions c t 1700-1400 b . c . and the period of the composition of the Rgveda c. 1200-1000 b . c . is not likely to be many centuries out, either one way or the other. There is some linguistic evidence to show that the Indo- Aryan invasion took place in successive phases, and not in one simultaneous movement. There are dialectal differences be- tween the Vedic language of the North West and the later classical language of Madhyadesa. The most striking of these is that the Vedic language turns l into r whereas the classical language, to a large extent, preserves the distinction between r and l. This Vedic feature is characteristic of the whole of Iranian, and furthermore it can be traced in the Aryan of the Near East and in some Aryan words in Finno-Ugrian. Clearly the fact that the more easterly dialects of early Indo-Aryan have avoided this change indicates a comparatively early separation from the main body, in comparison with the Vedic dialect which has undergone this change in common with the rest of Aryan before being introduced into India. Certain features of the Kafiri languages of the North West indicate important dialectal divergencies of ancient Aryan at a time preceding the invasion of India. In some ways these languages stand half way between Indo-Aryan and Iranian. They agree with Indo-Aryan in retaining s which Iranian changes to h, but with Iranian in the treatment of the two palatal series (e.g. zim f snow ' : Skt. himd-, jd- * kill ' : Skt. han). In this respect they form simply an intermediate dialect group, as might be expected from their position between the two main groups. On the other hand in their treatment of the sound which appears in Sanskrit as s they have preserved a form which is more archaic than anything found elsewhere in Indian and Iranian (c in cuna - 1 dog due 1 10 etc.). This can only be satisfactorily explained as the isolated preservation of a very ancient dialectal feature within Indo-Iranian. The same considerations apply to the absence of cerebralisation of s after u in words like dos * yesterday ' and musd ‘ mouse The change of s to s (>Skt. s) under specified conditions is, as we have seen, so ancient as to be shared by both Indo-Aryan and Slavonic, but it seems that some peripheral dialect of Indo- Aryan must have escaped it in connection with u, and it is from this source that the Kafiri forms are derived. The evid- ence would suggest that the Aryan dialect which preserved
