Grassmann's law in Greek and its diffusion in waves

The present paper aims at discussing the chronology of Grassmann’s law (GL), bearing in mind the possibility, put forward by KIPARSKY (1973), of a backdating of its operativeness. Thanks to the comparison between some “relic” forms and data taken from 2nd millennium Greek, we will try to speculate in relation to the chronology of this phonetic change. In particular, the hypothesis here advanced is that we are dealing with different “waves” of a single phenomenon, whose effects were prolonged over time, surfacing sporadically in time and space.