Caverns Measureless to Man

Bookshelf: Caverns Measureless to Man

Caverns Measureless to Man – Sheck Exley

Sheck Exley is a legend in diving circles in general, but his status is particularly for cave and deep diving. He was one of the originators of the sport of cave diving, driving around Florida in the 1960’s in his Beetle and diving in submerged springs and aquifers.

He put in place many of the basic safety features of the sport, such as the one thirds rule (penetrate the cave using one third of your air, and then turn around; this leaves a safety margin for emergencies). He was also a pioneer of extremely deep diving (akin to that practiced by Dave Shaw in Raising the Dead/Diving Into Darkness – Exley even dived Boesmansgat in 1993).

Caverns Measureless to Man
Caverns Measureless to Man

Exley set numerous records, both for depth dived and distanced penetrated into a cave. He died when he was only 45, attempting to dive to over 300 metres in a cenote (a fresh water vertical cave) in Mexico. The cenote project continues with many of his former team members – long before I became a diver, I found the El Proyecto de Buceo Espeleologico México y América Central website, and was fascinated.

This book is part memoir, part manifesto on cave diving. I was particularly interested to see how far scuba gear has come in the last half century. Some of the gear these guys used was DODGY! A lot of it was self-made or jury-rigged from conventional scuba gear. As a pioneer of a new sport, there was not sufficient demand for equipment manufacturers to justify building the kind of kit that was required. The photographs are hilarious… To a man, the divers all had a LOT of hair. And those masks must have taken eight or ten breaths to clear!

There are several lessons one can learn from Exley. The main one for me was that he did thousands – over 4000 in his 29 year diving career – of cave dives. That is why he was so good: he practiced. Constant repetition, staying in top form so that he could do what he loved, and do it well.

The second object lesson is hinted at in the title of the book. It is taken from a line in a Samuel Taylor Coleridge Poem, Kubla Kahn. Here’s the first few lines:

In Xanadu did Kubla Khan
A stately pleasure-dome decree:
Where Alph, the sacred river, ran
Through caverns measureless to man
Down to a sunless sea.

The essence of what appealed to Exley, and what attracts many technical divers to the sport today, is the opportunity to go where no one else has gone – to reach new depths, to walk on the moon or the top of Mount Everest, in the sense of being part of a very elite group of adventurers. This seems like an incredibly arrogant aim, but when you read Exley’s memoir you realise what a humble and grounded man he was. There was no swagger, or bravado, or careless abandon with his kit or his dive planning. Quite the opposite – the man was deadly serious about what he did, and I think that is why he lived so long. I am grateful every day that no one I love is a technical diver pushing the limits of the sport the way Exley and his team did… I feel that if you do this sport long enough, it’s what you will die doing. The dangers are extreme.

There’s a super Wired Magazine article on Sheck Exley and his diving partner Jim Bowden, here. It describes Exley’s final dive, providing a lot of background along the way. If it doesn’t make you want to read Exley’s book, then I have no hope for you!

You can order the book here.

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Lapsed mathematician, creator of order, formulator of hypotheses. Lover of the ocean, being outdoors, the bush, reading, photography, travelling (especially in Africa) and road trips.

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