The Ba Gua mirror is among the most well-known and commonly used of all the Feng Shui protection spells, remedies, or magical cures for improper placements of houses -- placements that may attract bad luck or lead to sorrow or illness in the dwelling. Buildings placed near graveyards, bridges, railroads, or overpasses, ot those at a T-intersection or with a large tree bocking the entrance are said to be at a disadvantage from "poison arrows" of sha that damage those inside the dwelling or place of business.
The Ba Gua is extremely powerful and should be used with care and also respect for others, as when you hang one they deflect the bad energy onto the offending object.
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