[color=a7a7a7]"I think you go through here, mister, but I don''t know where you are... or where I am, for that matter..."[/color]

As you step over the books and such, you find yourself stepping on a book titled "On the Species: The Believer". It's obviously an old book, written ages ago by some gnome known as Irthorne, but it might be helpful to you in your quest. However, the button in front of you is more concerning. The light cast by the fireball is shown on the button, highlighting the small needlelike object in the hole. Perhaps it's supposed to draw the blood of the presser in order to open the gate.

Either way, someone's gotta put their hand in there, or you are stuck.