In 1539, Vesalius acquired a large supply of bodies of executed criminals in order to work on De humani corporis fabrica. The manuscript was finished in 1542 and he took it to the printing press of Joannes Oporinus in Basel who published it the following year although a vastly improved second edition appeared in 1555. The technically (though not always anatomically) accurate illustrations were made by a Dutch artist, Jan Stephan van Calcar (1499-c. 1546), who had been a pupil of the Italian master, Titian (c. 1488-1576). There were over 300 illustrations of the skeleton and muscles, the nervous system, blood vessels and viscera. On the title page, the cadaver with the its gaping abdomen is the central figure. A skeleton points towards it. Vesalius himself looks out directly at the reader who has just opened the book as though extending an invitation to step inside the new world of anatomy.Source: Andreas Vesalius. De humani corporis fabrica. J Oporimus, 1555.