 Only three copies of the book survived but these remained hidden for decades, the rest were burned shortly after its publication in 1553 because of persecution of Servetus by religious authorities.Better known discovery of pulmonary circulation was by Vesalius's successor at Padua, Realdo Colombo, in 1559.Finally, the English physician William Harvey, a pupil of Hieronymus Fabricius (who had earlier described the valves of the veins without recognizing their function), performed a sequence of experiments and published his "Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus" in 1628, which "demonstrated that there had to be a direct connection between the venous and arterial systems throughout the body, and not just the lungs.