THUS far we have been considering chiefly that branch of sympathetic magic which may be called homoeopathic or imitative. Its leading principle, as we have seen, is that like produces like, or, in other words, that an effect resembles its cause. The other great branch of sympathetic magic, which I have called Contagious Magic, proceeds upon the notion that things which have once been conjoined must remain ever afterwards, even when quite dissevered from each other, in such a sympathetic relation that whatever is done to the one must similarly affect the other. Thus the logical basis of Contagious Magic, like that of Homoeopathic Magic, is a mistaken association of ideas; its physical basis, if we may speak of such a thing, like the physical basis of Homoeopathic Magic, is a material medium of some sort which, like the ether of modern physics, is assumed to unite distant objects and to convey impressions from one to the other. The most familiar example of Contagious Magic is the magical sympathy which is supposed to exist between a man and any severed portion of his person, as his hair or nails; so that whoever gets possession of human hair or nails may work his will, at any distance, upon the person from whom they were cut. This superstition is world-wide; instances of it in regard to hair and nails will be noticed later on in this work. Among the Australian tribes it was a common practice to knock out one or more of a boy's front teeth at those ceremonies of initiation to which every male member had to submit before he could enjoy the rights and privileges of a full-grown man. The reason of the practice is obscure; all that concerns us here is the belief that a sympathetic relation continued to exist between the lad and his teeth after the latter had been extracted from his gums. Thus among some of the tribes about the river Darling, in New South Wales, the extracted tooth was placed under the bark of a tree near a river or water-hole; if the bark grew over the tooth, or if the tooth fell into the water, all was well; but if it were exposed and the ants ran over it, the natives believed that the boy would suffer from a disease of the mouth. Among the Murring and other tribes of New South Wales the extracted tooth was at first taken care of by an old man, and then passed from one headman to another, until it had gone all round the community, when it came back to the lad's father, and finally to the lad himself. But however it was thus conveyed from hand to hand, it might on no account be placed in a bag containing magical substances, for to do so would, they believed, put the owner of the tooth in great danger. The late Dr. Howitt once acted as custodian of the teeth which had been extracted from some novices at a ceremony of initiation, and the old men earnestly besought him not to carry them in a bag in which they knew that he had some quartz crystals. They declared that if he did so the magic of the crystals