James Frazer, The Golden Bough — Chapter 62:… (1922)
“ The remains of the log were also supposed to guard the house against fire and lightning.To this day the ritual of bringing in the Yule log is observed with much solemnity among the Southern Slavs, especially the Serbians. The log is usually a block of oak, but sometimes of olive or beech. They seem to think that they will have as many calves, lambs, pigs, and kids as they strike sparks out of the burning log. Some people carry a piece of the log out to the fields to protect them against hail. ”
