In folklore, what substance can be placed at doorways to deter evil spirits?

Salt

Who is the fashion-obsessed villain of '101 Dalmatians'? Who was the king who built the first temple in Jerusalem? Which empire was led by Montezuma II when the Spanish invaded? Which running back set an NFL single-season rushing yardage record in 1984 that still stands? Which amendment lowered the voting age to 18 in the United States?