Burning the clavie is an ancient Scottish custom still observed at Burghead, a fishing village on the Moray Firth. The clavie is a collection of casks split in two, lighted as a bonfire in the evening of 11 January, i.e. New Year's Eve (in Scotland, Hogmanay) by the Julian Calendar.
When the burning tar-barrel/casks falls in pieces, the people scramble to get a lighted piece with which to kindle the New Year's fire on their cottage hearth. The charcoal of the clavie is collected and put in pieces up the cottage chimneys, to keep spirits and witches from coming down.
This is a video of the event that I made back in 2014: