
Zombies shamble. Werewolves howl. Witches cackle.
I'm not sure just when witches first began to cackle. Personally, I suspect the cackling witch to be a fairly recent development, perhaps even as late as the “Twentieth” Century. It may even be that we owe our cackling—as with so much else—to the Great Green-Faced Mother of Us All, the immortal St. Margaret Hamilton.
Still, whenever it is that we first began to cackle, we've made the sound our own. You hear “cackle” and you think “witch.” It's pretty delightful to have a verb of one's own.
It was not always thus. “Cackle” is an old word—all the Germanic languages have some version of it—denoting (probably imitatively) the sound made by a hen when she lays an egg.
The ancestors were astute observers of the world around them. If you've ever actually heard a hen cackle, you know what a distinctive sound it is: shrill, brittle, with a note of triumph to it.
The underlying metaphor here, then, is witch : hen. This actually makes a good deal of mythological sense. The sacred bird of the God of Witches is the—well, let me be coy here and say “rooster.” A cock's head figures on the coinage of the Dobunni, the Keltic tribe ancestral to the Anglo-Saxon Hwicce, the original Tribe of Witches. Witches, so they say, are hens to the Devil's cock, cows to the Devil's bull.
Oh, those earthy ancestors.