The Watermarks in the Rome Editions of Ptolemy’s Cosmography and More (Quaerendo) Authors: R.H.J. Peerlings, F. Laurentius and J. van den Bovenkamp The authors conducted a study to describe the watermarks appearing in the text and map pages of the early Rome editions of Ptolemy’s Cosmography in order to date individual maps. They visited several institutions and libraries in Europe in person to study the atlases. Information and photographs concerning their atlases from institutions and libraries in the United States were collected by email correspondence. Information on some atlases was found directly on the internet. The conclusion is that each edition is characterized by its own specific watermarks. Photographs of all the watermarks found in each edition are displayed in this article. Click here to go to the article New Findings and Discoveries in the 1507/8 Rome Edition of Ptolemy’s Cosmography (Quaerendo) Authors: R.H.J. Peerlings, F. Laurentius and J. van den Bovenkamp In a previous article the watermarks in the text and map pages of the Rome editions of Ptolemy’s Cosmography were described. This article shows how they can be used to reveal hidden knowledge about the development and chronology of the 1507/8 Rome edition of Ptolemy’s Cosmography. It also discusses the discovery of new states of three maps and the appearance of the Ruysch world map in these editions. Atlases in several institutes and libraries in Europe were studied firsthand, whereas information and photographs of atlases in libraries in the United States were collected by e-mail correspondence and internet downloads. Click here to go to the article

The 1478, 1490, 1507 and 1508 Rome editions of Ptolemy's Cosmography including the Ruysch world map and their watermarks