On this primitive principle, possession of a thunderbolt gives you some sort of hold, as it were, over the thunder-god himself in person. If you keep a thunderbolt in your house it will never be struck by lightning. In Shetland, stone axes are religiously preserved in every cottage as a cheap and simple substitute for lightning-rods. In Cornwall, the stone hatchets and arrowheads not only guard the house from thunder, but also act as magical barometers, changing colour with the changes of the weather, as if in sympathy with the temper of the thunder-god. In Germany, the house where a thunderbolt is kept is safe from the storm; and the bolt itself begins to sweat on the approach of lightning-clouds. Nay, so potent is the protection afforded by a thunderbolt that where the lightning has once struck it never strikes again; the bolt already buried in the soil seems to preserve the surrounding place from the anger of the deity. Old and pagan in their nature as are these beliefs, they yet survive so thoroughly into Christian times that I have seen a stone hatchet built into the steeple of a church to protect it from lightning. Indeed, steeples have always of course attracted the electric discharge to a singular degree by their height and tapering form, especially before the introduction of lighting-rods; and it was a sore trial of faith to mediaeval reasoners to understand why heaven should hurl its angry darts so often against the towers of its very own churches. In the Abruzzi the flint axe has actually been Christianised into St. Paul's arrows--_saetti de San Paolo_. Families hand down the miraculous stones from father to son as a precious legacy; and mothers hang them on their children's necks side by side with medals of saints and madonnas, which themselves are hardly so highly prized as the stones that fall from heaven.