The Origin of English Words

graham identified a series of sound changes which has occurred in a systematic way from the original indo european language through the germanic languages. And the changes became known as graam's law. But grimm did not actually call them a law. While he noticed that these consonants usually shifted in the way he described, they did not always shift that way. We see grim's law at work in how these two sets of words evolved from the same source word.