Thus it's obvious that Petra Sancta got the model for his system from the illustrators and publishers of his books in the Low Countries. It is possible that these engravers also knew at least two earlier hatching systems: Zangrius' in 1600 and Francquart's in 1623. The techniques might have even been carried forward by the guilds of engravers one after another. Certainly, Petra Sancta must have at least held consultations with the engravers who were preparing illustrations for his books to explain his concept or to develop a coherent method to designate tinctures by mutual agreement.