andybrooks
Active member
I always thought that the "Rule of Thirds" was developed by Sheck Exley. However, it seems that Bob Leakey might have a much earlier claim. In "The Caverns of Mossdale Scar", he wrote "I had practiced holding my breath for as long as I could counting up to 79, 80, 90 a hundred and so on. I used to have this very strict system that I could just go one third of how much breath I could hold, and then I had to turn around which sometimes took a whole third, another third and then get out as quick as I could."