Generations of Irish dancers may have stepped their way across the stately homes of Ireland, modest country cottages and even bridges over a local river without ever realising there were horses skulls buried beneath them.
In some cases, the skulls had coins placed inside them.
It may seem a macabre thought but there was method in the madness, according to scholars and folklorists.
Our first reaction might be to think it was something to do with ancient Celtic traditions, superstitions or even the occult.
The real reason, however, may be more practical. The scholarly website, Daily Jstor has unearthed documents revealing that the skulls were intended simply to add an echo to the floor that would enhance the sound of dancers and the music.
It quotes Seán Ó Súilleabháin, who was an archivist at the Irish Folklore Commission. In 1945 Ó Súilleabháin published some of his research, quoting elderly people who could remember the skulls being used.
He wrote: “I used hear the old people say that it was put there for the purpose of giving a fine hearty echo (macalla) to the house when people would be talking or walking inside the house. But, particularly, they put the head (with the coppers) in the floor so that their dancing would sound better, for the old people were all for sport.”
Ó Súilleabháin revealed that a horse skull was installed under a bridge in Co Kerry “to give it a clear echo”. In Wexford, skulls were placed below church altars to “help the preacher to be heard all over the church. In some churches up to twenty of these heads were buried together.”
Superstition may also have played a part, however, with some people believing that horse skulls brought good luck and were able to ward off evil spirits.