Stories about extreme survival are alluring not just because they get about as close to death as it’s possible to go, but because they reveal life in all its sinewy tenaciousness. Both these books are founded on astonishing near-death tales, but where one seems to lean across the final boundary, the other hangs onto it with fierce determination. The Survivors Club is a gutsy, fact-thick book on luck, accident and improving the odds. It’s all about clinging on. The Third Man Factor is a more thoughtful investigation of a strange “presence” felt by lonely explorers. As such, it’s more concerned with people who seem to be wilfully relinquishing their grip.

Certainly, the “third man” only seems to appear when death is very, very close. A delirious Joshua Slocum experienced him as an “invisible helmsman” who guided his 12-metre sloop through the worst storms of his solo circumnavigation of the world in 1895–98. In 1916, Ernest Shackleton and his companions sensed him as an impalpable “extra” as they crossed the mountainous interior of South Georgia, tentless and in rags after an unplanned, 1,000km journey in an open boat. In 1933, he visited the mountaineer Frank Smythe as he paused at the highest point yet reached on Everest. Exhausted by the thin air, Smythe found himself sharing Kendal mint cake with an imagined companion who elimin-ated all sense of loneliness and gave him the feeling “that if I slipped ‘he’ would hold me”.

Inevitably, given the sense of comfort he brings, some have interpreted the third man as a divine messenger. Geiger has more to say about less closed interpretations, such as that provided by Reinhold Messner, the preeminent Himalayan climber of the post-war period. ­During his disastrous ascent of Nanga Parbat, in 1970, in which his brother died, Messner was visited by a “third climber”, a figure who kept “a regular distance a little to my right and a few steps away from me, just out of my field of vision”. On later expeditions, Messner read this climber as his brother, but he originally wondered if the third man was not himself seen from “a different plane of existence” — a kind of Conradian Secret Sharer, maybe.

As Geiger rattles through the classic accounts from exploration literature, it’s all thrilling enough, but somehow collecting the various experiences together means they lose some of their strangeness. The book isn’t well served by its foray into brain science, either. Geiger is less comfortable with, say, malfunctions of the temporoparietal junction than he is in an open boat in a storm or deep in the Himalayan death zone. Ultimately, he rejects neurological explanations just as he does theological ones. He prefers the line taken by the poet and ­Everest ­mountaineer Wilfred Noyce, who argued that the third man is a kind of internal SOS system; not an angel but an “angel switch”, a “secret and astonishing capacity of mind” that offers “a real power for survival”.

The Survivors Club is interested in exactly that mental capacity, but has a rough-and-tumble way of in-vestigating it. It tells you exactly what happens when you eject from a fighter jet at Mach 1 (shattered ribs, severed ligaments, exploded blood vessels), what it feels like to be adrift in the Gulf of Mexico and give up (nothing hurts any more), how people survive falls from great heights (they black out, their bodies relax and they land in a particular kind of snow) and ways to survive a plane crash (sit within five rows of an exit, memorise an escape plan, bring a smoke hood whose breathing filter can protect you against toxic gases, and identify potential weaklings among the passengers).

But this isn’t just a survivors’ manual, it’s an inquiry into the the mindset that characterises the survivor. Hard facts mix with softer psychology. People have their faces torn off by mountain lions, they sink on board ferries outside Zeebrugge and fall out of exploding planes six miles up without a parachute. They find themselves drawing on resources they didn’t know they had. In the theory of 10-80-10, they are the 10% who react to a crisis with reason and resolve, not the 80% who find themselves “stunned and bewildered”, still less the 10% who freak out.

The drawback — and fascination — of The Survivors Club is that most of the case studies terrify as much as they inspire or inform. Take Jerry Schemmel, a passenger aboard United 232 when it smashed, rudderless, into the tarmac at Sioux City airport, Iowa, in 1989. Yes, the pilot’s skilful manoeuvres saved the lives of over half the passengers. Yes, Jerry got out, and even rescued a baby from the burning wreckage. But the heroics pale beside the image of Jerry hanging upside down from his seatbelt, burning and watching the limbs of his fellow passengers flailing, and their blood “streaming down like rain”.

Or take Kevin Hines, one of only 28 would-be suicides to leap off the Golden Gate bridge and live. Typically, we are informed, a jumper’s heart is ripped loose on impact and their ribs dice their internal organs “like a bread slicer” before they plunge 80ft into the powerful currents of the strait. Hines was lucky. He hit the water in just the right way (feet first, at a slight angle — make a note), surfaced alive and was kept afloat by a curious — some say altruistic — sea lion long enough to be rescued.

Looking up from the bay at the bridge, Hines said, is “one of the scariest things you’ll ever imagine”. But it has some competition in The Survivors Club. Among the many eyebrow-raising statistics revealed by Sherwood is that the chance of having a stress-induced coronary in the air is far higher than that of dying in a crash. He doesn’t calculate the risk of expiring from the stress of reading his book, but, if your heart is racing and you’re wondering where to buy a smoke hood, it might be safer to turn to The Third Man Factor instead. It will certainly be more provocative of thought, and less of anxiety.

The Survivors Club by Ben Sherwood
M Joseph £15.99 pp383
The Third Man Factor by John Geiger
Canongate £12.99 pp320

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