Willem Janszoon Blaeu, who was born at Alkmaar in 1571 and trained in astronomy and the sciences by Tycho Brahe, the celebrated Danish astronomer, founded a business in Amsterdam in 1599 as a globe and instrument maker. It was not long before the business expanded, publishing maps, topographical works and books of sea charts as well as constructing globes. Blaeu was planning a major atlas intended to include the most up-to-date maps of the whole of the known world but progress on so vast a project was slow and not until he bought between 30 and 40 plates of the Mercator Atlas from Jodocus Hondius II to add to his own collection was he able to publish, in 1630, a 60-map volume with the title Atlantis Appendix.