Halldór Laxness said this quote
“ Can't we make a blusterer ourselves? asked Jón Hreggviðsson. Can't we scratch that damned sign with the ax-point onto the chopping block and get a beautiful, chubby woman in here tonight, right now-or preferably three? It was no easy matter to create such a sign, because in order to do so the two men required much greater access to the animal kingdom and the forces of nature than conditions in the dungeon permitted. The sign of the Blusterer is inscribed with a raven's gall on the rust-brown inner side of a bitch's skin, and afterward blood is sprinkled over the skin - blood from a black tomcat whose neck has been cut under a full moon by an unspoiled maiden. Where'd you find an unspoiled maiden to cut a black tomcat's neck asked Jón Hreggviðsson. ”