Edward Lovett's amulets

There is a fascinating exhibition 'Charmed Life' on at our Discovery Centre here in Winchester. Along with work by artist Felicity Powell, it includes a large collection of amulets or charms once carried in the pockets of Londoners for luck or protection, assembled by the Edwardian folklorist Edward Lovett.
They made me realize how many things I have collected and used as charms ever since I was little.
According to the exhibition catalogue circular stones
with a hole were tied to a cow to prevent fairies stealing the milk. A small stone with a hole in it (I have some on my key rings) is thought to be lucky if found unexpectedly and two stones with natural holes tied together are meant to prevent nightmares.
These are some of my holey stones collected from near and far from Dorset right down to South Island, New Zealand. I must tie two together .