A Note on ¾ as 'ss' [šː] and a ruki-Rule in Ancient Greek
There are in Ancient Greek a few hints of a ruki-development (that is, the change of [s] to [š]--in Sanskrit, to [ʂ]--when preceded by k, r, i, and u).1 Till now, the change has been thought to have been limited to a few other Indo-European language families. The evidence presented here has chiefly to do with otherwise unaccountable switchings of Greek σσ with ξ and the fact that the examples occur in ruki-environments. It will become obvious that σσ (known to have represented [šː])2 and ξ had to represent the same sound at some time in this or that place: evidence will be adduced to show that ξ represented [šː] (short where long consonants were not permitted) in the relevant lects.
The crucial evidence of the alternations of ξ with σσ is qualitatively solid and very important; but like certain archaeological fossils, it is quantitatively meagre and will require detailed and at times tedious examination and argumentation. It is important to consider the psychology of an orthography as well as the probable phonetological developments behind it. That 'x' [cs] could become [š(ː)] is not in doubt: It happened in western Romance, where it was represented by 'ss' in French and by 'x' in Iberia.3____________________
However that may be, later borrowings complicated the results in French: compare current laisser