Howard Covitz - The astrolabe is an astronomical calculator dating back at least 2000 years. Once you have walked through how to use the darn thing, you will appreciate firsthand just how much "they knew back then".
You can submit your own idea at http://ignitephoenix.com/submissions
Who was changing your slides??? I wish you had more time because you actually know what you're talking about!
OKcomp 1 month ago