At any other time, Jack might be more than enthusiastic at the idea of doing something a little bit dangerous. He did a lot of things that were dangerous, and many of them, he took undue pleasure in.

But now, right now, he was aprehensive and nervous. He looked at the squares on the floor with an uncertain gaze, and then back up to the Doctor.

"Are you sure?" he asked, his voice all twinged with trepidation. "I mean, it's pretty far isn't it, and what if something happened, what if something went wrong, what would we do? What if you got hurt?"

He heard himself, and that bit of his mind that still had its sense wanted to smack himself firmly around the face and tell himself to snap out of it.

So that need, that little voice triggered him back out of it and back into confidence. He looked at the floor again and, well it didn't seem that far.

"Right!" he nodded, "jump it, course we can, you and me, right?"