A merchant had done a good business at the fair; he had sold his wares and lined his money-bags with gold and silver. Then he wanted to travel homeward and be in his house before nightfall. So he packed his trunk with the money on his horse and rode away. At noon he rested in a town, and when he wanted to go farther the stable-boy brought out his horse and said: “A nail is wanting, sir, in the shoe of its left hind foot.” “Let it be wanting,” answered the merchant; “the shoe will certainly stay on for the six miles I have still to go; I am in a hurry.” In the afternoon, when he once more alighted and had his horse fed, the stable-boy went to him and said, “Sir, a shoe is missing from your horse’s left hind foot; shall I take him to the blacksmith?” “Let it still be wanting,” answered the man, “the horse can very well hold out for the couple of miles which remain; I am in haste.” He rode forth, but before long the horse began to limp. It had not limped long before it began to stumble, and it had not stumbled long before it fell down and broke its leg. The merchant was forced to leave the horse where it was, and unbuckle the trunk, take it on his back, and go home on foot. And there he did not arrive until quite late at night. “And that unlucky nail,” said he to himself, “has caused all this disaster.” Hasten slowly. II. THE HORSE-SHOE AS A SAFEGUARD Your wife’s a witch, man; you should nail a horse-shoe on your chamber-door.—SIR WALTER SCOTT, _Redgauntlet_. As a practical device for the protection of horses’ feet, the utility of the iron horse-shoe has long been generally recognized; and for centuries, in countries widely separated, it has also been popularly used as a talisman for the preservation of buildings or premises from the wiles of witches and fiends. To the student of folk-lore, a superstition like this, which has exerted so wide an influence over men’s minds in the past, and which is also universally prevalent in our own times, must have a peculiar interest. What, then, were the reasons for the general adoption of the horse-shoe as a talisman? It is our purpose to consider the various theories _seriatim_. Among the Romans there prevailed a custom of driving nails into cottage walls as an antidote against the plague. Both this practice and the later one of nailing up horse-shoes have been thought by some to originate from the rite of the Passover. The blood sprinkled upon the door-posts and lintel at the time of the great Jewish feast formed the chief points of an arch, and it may be that with this in mind people adopted the horse-shoe as an arch-shaped talisman, and it thus became generally emblematic of good luck. The same thought may underlie the practice of the peasants in the west of Scotland, who train the boughs of the rowan or mountain-ash tree in the form of an arch over a farmyard gate to protect their cattle from evil.