Here is my answer to the critisism of Gary Thompson on my 5,500 BC dating of the path-positions of the Astrolabe.  Thompson voiced his thoughts in the Internet space on his WEB Page  http://members.westnet.com.au/gary-david-thompson/page9e.html .

The story      "Koch Johannes, NABU and The Astrolabe"  Part III,   Last part of the story

The story      "Koch Johannes, NABU and The Astrolabe"  Part II

The story     "Koch Johannes, NABU and The Astrolabe"  Part I

Describes version 1.10 of Porphyrius Magus.