The castle of knowledge. To knowledg is this trophy set,/ All learninges friendes will it support./ So shall their name great honour get,/ And gaine great fame with good report ...
Lettering continues: "Though spitefull Fortune turned her wheele/ To staye the sphere of Urayne,/ Yet dooth this sphere resist that wheele,/ And fleeyth all Fortunes villayne./ Though earthe do honour Fortunes balle,/ And bytells blynde hyr wheele advaunce,/ The heavens to fortune are not thralle/ These spheres surmount al fortunes chance". On the left, a woman standing on a cube holding a compass holds up a gyroscope labelled: "The sphere of destinye. Whose governor is knowledge. Sphæra fati". On the right a blindfolded woman standing on a sphere holds up a wheel on on which is written: "Ovi modo scandit corruet statim". The wheel is labelled: "The wheel of Fortune. Whose ruler is ignoraunce. Sphæra fornæ"
Verso contains lettering detailing the contents of the four treatises in the book: 1. introduction to the sphere; 2. the making of the sphere; 3. use of the sphere 4. further demonstrations. It ends with a poem: "If ought here want, that you desire,/ Remember where this work was wrought:/ In Plutos forge with scarse good fier/ This rustye sphere to eande was brought./ But if I may it fyle agene,/ The ruste I truste to scour of clene"
