Thursday, September 16, 2004
Explanation:
This is a woodblock print dating from 1690. It seems to be a common print from that era for a couple of copies have appeared on eBay over the last two years. It shows a delightful, well-composed scene, with a long aerial telescope aimed at the Moon from within a courtyard filled with people apparently in line for a view. The map is a pretty good copy and simplification of Hevelius' 1647 full Moon map. Comparison of the length of the telescope tube with people standing near it (assumed to be 5'6" tall) gives a length of 40 ft (~13 m). Hevelius did have telescopes of 60 and 70 ft focal length (according to King's The History of the Telescope), and he used wooden tubes as shown. I deduce this print shows Hevelius' work, both the map and telescope. At the bottom of the print are some words in Dutch that were partially translated using a neat capability associated with the Apple OS. I believe it says: A view of the Moon following the newest information from the largest telescopes. It could almost be a recent NASA press-release! In the last 5 minutes, I've found a web site that confirms my translations and identifies the book the print was in as Joodsche Oudheden of Voorbereidselen tot de Bybelsche Wysheid en Gebruik der Heylige en Kerkelyke Historien by Willem Goeree (1635-1711). You will have to go to the website to find out more. By the way I have observed the Moon with a telescope like this. My friend Alan Binder built a 17 ft focal length, 2.5" aperture Hevelian single lens telescope. I was impressed with the resolution - it was comparable to a similar aperture modern achromat, but a lot more fun to use!
