In the foregoing cases a person is supposed to influence vegetation homoeopathically. He infects trees or plants with qualities or accidents, good or bad, resembling and derived from his own. But on the principle of homoeopathic magic the influence is mutual: the plant can infect the man just as much as the man can infect the plant. In magic, as I believe in physics, action and reaction are equal and opposite. The Cherokee Indians are adepts in practical botany of the homoeopathic sort. Thus wiry roots of the catgut plant or devil’s shoestring (_Tephrosia_) are so tough that they can almost stop a ploughshare in the furrow. Hence Cherokee women wash their heads with a decoction of the roots to make the hair strong, and Cherokee ball-players wash themselves with it to toughen their muscles. To help them to spring quickly to their feet when they are thrown to the ground, these Indian ball-players also bathe their limbs with a decoction of the small rush (_Juncus tenuis_), which, they say, always recovers its erect position, no matter how often it is trampled down. To improve a child’s memory the Cherokees beat up burs in water which has been fetched from a roaring waterfall. The virtue of the potion is threefold. The voice of the Long Man or river-god is heard in the roar of the cataract; the stream seizes and holds things cast upon its surface; and there is nothing that sticks like a bur. Hence it seems clear that with the potion the child will drink in the lessons taught by the voice of the waters, will seize them like the stream, and stick fast to them like a bur. For a like reason the Cherokee fisherman ties the plant called Venus’ flytrap (_Dionaea_) to his fishtrap, and he chews the plant and spits it on the bait. That will be sure to make the trap and the bait catch fish, just as Venus’ flytrap catches and digests the insects which alight on it.​[501] {p145} The Kei islanders think that certain creepers which adhere firmly to the trunks of trees prevent voyagers at sea from being wafted hither and thither at the mercy of the wind and the waves; the adhesive power of the plants enables the mariners to go straight to their destination.​[502] It is a Galelareese belief that if you eat a fruit which has fallen to the ground, you will yourself contract a disposition to stumble and fall; and that if you partake of something which has been forgotten (such as a sweet potato left in the pot or a banana in the fire), you will become forgetful.​[503] The Galelareese are also of opinion that if a woman were to consume two bananas growing from a single head she would give birth to twins.​[504] The Guarani Indians of South America thought that a woman would become a mother of twins if she ate a double grain of millet.​[505] In Vedic times a curious application of this principle supplied a charm by which a banished prince might be restored to his kingdom. He had to eat food cooked on a fire which was fed with wood which had grown out