article_snippet.sent: What the hell am I doing, I ask myself, as I stand shivering on the brink.
article_snippet.sent: Gasping for breath, I take the plunge.
article_snippet.sent: Scroll down for video .
article_snippet.sent: Why does it affect me so?
article_snippet.sent: But I was scared to go in.
article_snippet.sent: The problem was I couldn’t see the bottom.
article_snippet.sent: It’s bad enough trying to keep your feet as you stagger in.
article_snippet.sent: I’m often hurled flat on my face and have to scrabble over the stones on my stomach. 