Originally posted by k1man was pentax the first to bring out a fisheye zoom
Yes, with the F 17-28mm, introduced, I believe, in the mid-nineties for 35mm film cameras. About ten years later Pentax introduced the DA 10-17 for digital APS-C. There's a DFA fisheye zoom on Pentax's current roadmap, slated for 2019 or later.
Canon introduced an 8-15mm fisheye zoom a few years back. It's an expensive L lens of high quality, but, unlike the Pentax fisheye zooms, it starts out as a circular fisheye and zooms into a normal fisheye. Nikon is soon releasing a very similar fisheye lens. I honestly don't get this design, as I don't find circular fisheye images all that compelling. I vastly prefer Pentax's way of doing it, which involves starting at the normal fisheye FOV and zooming to a narrower FOV.
Another image of Smith River in NoCal with KP: