Keywords: Nocturnal, Erasmus Habermel, Prague, c. 1600, tell time at night by sighting Pole Star through central hole, then align pointer with Big Dipper - Mathematisch-Physikalischer Salon, Dresden - DSC08017.JPG en Exhibit in the Mathematisch-Physikalischer Salon Zwinger Dresden Germany This artwork is old enough so that it is in the public domain Photography was permitted in the museum without restriction 2013-12-08 07 23 37 own Daderot other versions PD-old-70 cc-zero Collections of Mathematisch-Physikalischer Salon Zwinger Dresden Uploaded with UploadWizard Erasmus Habermel Nocturnal |