Who Invented the "Newtonian Reflecting" Telescope?

OK, OK, sounds like a dumb question, but, as I was looking up information about this kind of scope I repeadedly came across tidbits like:

REFLECTING TELESCOPE
A reflecting (or Newtonian) telescope uses two mirrors to magnify what is viewed. The reflecting telescope was first described by James Gregory in 1663.

So, if JG was the first to describe it, then where does Sir Isaac fit in? Was he the first to actually build one? Or does it just use some of Newton's principles?

thanks

I believe Newtonian and Gregorian reflectors are different. Normally Gregorian optics in non-inverting and there is no virtual image formed. Cheap binoculars ($5) are often Gregorian in design because no prisms are needed. However the FOV is quite limited.

Here is some info on the Gregorian, notice the that Newtonian uses a flat secondary..
http://studio.cloudnet.com/clubowen/Arecibo.html

"What is a Gregorian Reflector System? Glad you asked. A Gregorian reflector system, named after the17th century mathemetician who devised the concept, involves a parabolic mirror with a small concave secondary reflector. The Gregorian at Arecibo uses two reflecting surfaces or mirrors, one 72 feet in diameter, the other 26 feet. The dome contains these two reflectors as well as the radar transmitter and microwave receivers."

jon isaacs

I thought Rick Singmaster invented the Newtonian. Perhaps he just perfected it.

Randy--heh, heh

Phil Rounesville built a 6" f/31.2 Gregorian (Sky & Telescope, January 1992, pages 16-17) that is usually on display at the Stellafane Convention. I've looked through it a number of times at Saturn and other targets appropriate for its long focal length.

Here's an image of a Gregorian of antique vintage:

http://www.arm.ac.uk/history/instruments/Adams-Gregorian-reflector.html

Dave Mitsky