The full name of this Class B document by Aleister Crowley is Liber 777 Vel Prolegoma Symbolica Ad Systemam Sceptico-Mysticae Viae Explicande, Fundamentum Hieroglyphicum Sanctissimorum Scientiae Summae.
It consists of roughly 200 columns, with each row corresponding to a specific Sephirah or path on the Tree of Life for a total of 35 rows. The columns cover Gematria, Mythical Gods and Goddesses, Colours, Animals, Plants, Spices, Astrology, etc.
The core of the material is a transcription from various initiation rituals and teachings of the Hermetic Order of the Golden Dawn. The rest came from his extensive study of the different religious and magical systems of the world.