Verner’s law

In HISTORICAL LINGUISTICS and PHILOLOGY, a SOUND CHANGE, first worked out by the Danish linguist Karl Verner (1846–96), which explained a class of apparent exceptions to GRIMM’S LAW. He found that Grimm’s law worked well whenever the STRESS fell on the ROOT SYLLABLE of the Sanskrit word; but when it fell on another syllable, the CONSONANTS behaved differently. VOICELESS PLOSIVES then did not stay as voiceless FRICATIVES, but became voiced plosives.