Where does the Ignotum Press logo come from and what does it signify?

Our logo is derived from a printing mark used by Henricus Petrus. He and his son ran a celebrated printing house in Basel in the 16th century.

The stone is a reference to the family name.

It also depicts a biblical motto from Jeremiah 23:29 which they would sometimes print in Latin, Greek or Hebrew in their books.

'Is not my word like fire, like a hammer that shatters stone?'

The frontispiece above comes from The Complete Book on the Judgement of the Stars. Other books printed by Petrus and his son included Copernicus De revolutionibus orbium coelestium and RegioMontanius and Santbech's De Triangulis Planis et Sphaericis libri quinque, the first systematic treatise on plane and spheric trigonometry to be published in Europe.

More here.