Geomancy is the Western equivalent of I Ching; it was originally practised by making marks with a stick in the earth and converting the marks symbols into a binary system of symbols.
It was introduced into Ceremonial practices by Aleister Crowley, and is also taught in many Wiccan traditions.
Crowley's book however, was always a little confusing, and this book by Hartmann provides a much clearer and more useful explanation of this divinatory exercise.
In addition to the thorough explanation and exploration of the 16 geomantic symbols, the book also contains 2048 answers to 16 questions. The questions themselves are a little odd and a little dated, such as : 'Are the servants honest?' and 'Will the expected letter arrive?'. They do at least provide examples of how to read the symbols in context.
Notwithstanding the above, on the whole this revised edition of an esoteric classic first published in 1913 brings an ancient art of divination into the 21st century, and any serious student of geomancy would benefit from owning it.