Chapter 28 shoe found on a road or field, and nailed either on or above the door of a house or stable, was considered a protection from spells.

I have seen horse-shoes hanging by a string above a door, and likewise nailed with the open part upwards, on the door lintel, but quite as often I have observed that the open part is downwards; but however hung, on enquiry, the object is the same, viz., to secure luck and prevent evil.