It was in fact an atlas of the planet, based on the maps Pei Shan-wei and her team made at the time of the original terraforming. The master maps from which all copies in the book were made were carefully hidden away in the Temple of God, as they were considered among the Church's most valuable artifacts. (OAR)
The original Book of Hastings was made of advanced synthetics which were fireproof, waterproof, and as tough as a five-millimeter sheet of hammered copper. Within the book, it stated that it was required that copies of its maps be made available to the public, as well as the Church, in the cathedral of every bishop.