The fifth month is regarded as the most "poisonous" of all the months in the year, and antidotes and charms of all kinds are necessary to repel the deadly influences that assail suffering humanity at this period. Children are protected from the many dangers that surround them by tying bands of parti-coloured silk threads round their fore-arms. Among the most efficacious family-charms is the mugwort plant (_Artemisia moxa_), which is hung over every doorway. Prof. Giles cites an old saying to the effect that "if on the _Tuan Wu_ festival one does not hang up mugwort, one will not eat any new wheat"; and explains it by the comment that a famous rebel named Huang Ch'ao gave orders to his soldiers to spare any family that exhibited this plant at its door. But the superstitious use of mugwort is far more ancient than any such story would imply. Its extreme antiquity is shown by the fact that this plant has been similarly used as a valued charm against evil in other parts of the world, including France, Germany and Britain.[148] The custom in such lands was to pluck the plant at the summer solstice (Midsummer Day) and to wear it on the person or (as in China) to hang it over the doorway. This is only one of innumerable examples of the strange unity that seems to underlie old popular customs and superstitions all the world over. In spite of the terrible potency of the evil things rampant during the fifth month, it is supposed in Weihaiwei that from sunrise to sunset on the fifth of the month (the festival we are now considering) all poisonous and destructive influences--material and spiritual--totally disappear, perhaps owing to the efficacy of the charms universally used against them on that day. It is believed that even poisonous plants are absolutely innocuous if plucked and eaten on the fifth of the fifth moon, while medicinal herbs attain their supreme degree of efficacy.