'Talisman to vitalize the tongue. It is to be used under the sign of the thrid brand of the Twelve Earthly Branches, with corresponding symbolic animal Tiger, Zodical sign Gemini, hours 3-5 a.m., and point of compass East-North-East. It represents the Vital Energy (ch'i) of the purple clouds of the Centre of Heaven....'
I have this wonderful book which I look at quite a lot, but rarely read. Its called 'Tao Magic The Secret Language of Diagrams & Calligraphy' by Laszlo Legeza.