"Prospectiva communis domini Johannis Archiepiscopi Cantuariensis, . . Fratris ordinis minorum dicti psau ♃ ad unguem castigata per eximium artium et medicine ac juris utriusque doctorem ac mathematicum peritissimum D. Facium Cardanum Mediolanensem in venerabili colegio juris peritorum Mediolani residentem. The subject of the treatise is not what is now called perspective... but it is principally concerned with elementary propositions of optics, such as the incidence of rays of light, reflexion and refraction, the non-existence of colour without light, the construction of the eye, the appearance of objects at a distance (viz., spheres as planes, and squares as oblongs); and spherical, cylindrical, and concave mirrors, whose property of conveying heat is described. The work is divided into three parts... The third treats of the stars, the rainbow, and the milky way."