Nine million litres of angry river race past my ankles and roar over the cliff. The lip of the world's greatest waterfall is 20ft away. I inch a little deeper. Frothing currents rip at my legs as my toes search for a grip. Spray rises a thousand feet in the air. A single slip and I'm gone.
"There is where we swim," says my guide Eustace, pointing at a circle of black water surrounded by raging surf, that's on the very edge. "There is safe."
Welcome to the Victoria Falls, adrenalin centre of Africa. Some come here to bungee from the bridge, microlight above the spray, or raft the white water that explodes from the gorge below. But I've come in search of the explorer David Livingstone, born 200 years ago this week, on 19 March 1813. And where better to start than Livingstone Island, perched above his greatest discovery, where I'm about to defy both gravity and sanity by swimming in the Angel's Pool.
Eustace holds out a hand and I grab it. Together we teeter along a submerged ridge of stones towards a ragged boulder. I scramble over and down the other side, plunging waist-deep into dark water – then deeper – then my feet find a hold and I'm up to my neck but standing firm. I turn around to look.
On every side a torrent of jagged water surges towards the lip. We are five feet from the drop. But the pool is calm. I stare across the rim of the falls, where a thousand miles of the Zambezi's flow are tumbling into space. The river is at its fullest, which is the only time you can swim in the Angel's Pool. It's possible in the rainy months from January to March, or June to August. Discovered just last year, it's a high-water alternative to the better known Devil's Pool, which is unreachable right now.
I duck my head under water, like a baptism in this wild place, then bob up and grin at Eustace. He throws me a thumbs up. Then we clamber back to the island and safety – and lunch.
"Scenes so lovely must have been gazed upon by angels in their flight," is how Livingstone described the falls. And it was from this island that he was the first European to see them, in 1855. Padding back through the reeds, we pass a stone monument to him. Eustace pauses. "Dr Livingstone was very important for us here in Zambia. He opened up this part of Africa for the outside world, for Christianity, and for the fight against the slave trade."
The doctor would be delighted to be remembered like this. He spent 32 years trekking through the wilder parts of southern Africa in pursuit of just those aims. From 1841 he made a series of journeys into the unexplored interior, at first with European companions and later alone with local porters. He preached the gospel, mapped the territory and reported on the horrors of the Arab slave trade – which helped to end it. Along the way he lost his wife to malaria, suffered terrifying diseases and dangers, and finally failed to find the source of the Nile. He only ever made a single convert – a tribal chief who lapsed back into polygamy. But his indomitable spirit made him the greatest hero of the Victorian age, and inspired a generation of Britons to open up the countries we now know as Zambia, Botswana, and Malawi.
Livingstone left the island by dugout canoe, but today I have Captain Viny and his motorboat – a steel dart that spins a terrifying line parallel to the mile-wide rim and then back up the swirling river. Ten minutes upstream, Viny moors us in smoother waters beside the clipped lawns of the Royal Livingstone Hotel. It's a splendid white colonial-style place, where zebras wander beneath the trees and tea is served on the veranda. In the cool of its long bar, beneath whirring fans, an 1847 map on the wall shows the doctor's many journeys.
Charming as it is, this stuff was not here in Livingstone's day. When he tramped through, this was raw bush with a populace ravaged by Arab slavers. The Tonga tribe used the island to sacrifice goats to the gods of the falls. Colonisation was the remedy the doctor prescribed for such ills, arguing in books and lectures that Africa needed "Christianity, commerce and civilization". He became the moral champion of empire, and within 10 years of his death in 1873 the first British settlers arrived.
Looking for their ghosts, I catch a car into the nearest town – called Livingstone, of course. It's a delightfully sleepy place, its main roads lined with stuccoed colonial buildings and gaggles of teenagers. There's a Stanley House, named after the fellow explorer who famously found him lost in the bush, a David Livingstone Church, and a fast-food joint called the Hungry Lion. But the highlight for me is the museum, which houses a unique collection of his personal possessions.
It's an odd sensation to stand in front of a glass case displaying the battered metal medicine chest with which Dr Livingstone fought off the malaria and dysentery that dogged his travels. Or the flintlock musket that he used to subdue wild animals, mutinous porters and hostile tribes. Here's his field notebook, with a sketch of the falls in navy blue. And there's his hat, the famous blue kepi with its band of gold. Finally, by the door, is a black tin trunk whose lid is stained with blobs of black wax, where every night he fixed a candle to write up his journal.
The trunk was by his bed on the morning in the swamps of northern Zambia when his African servants found him, hours dead, but kneeling in prayer.
Astonishingly, they wrapped his body in tree bark and carried it over a thousand miles to the coast, where a British warship took it home. Livingstone had a state funeral in Westminster Abbey, attended by the Prime Minister and the Prince of Wales. But his heart was left in Africa, buried beneath a tree at the request of the local chief.
I drive slowly back to my hotel. It's not the sort of place where he would have stayed. The cutting edge of travel in Zambia today is the luxury lodges on the banks of the Zambezi. And I am staying in one of the loveliest: Tongabezi. It's a scattering of glorified African rondavels – round huts with thatched roofs – among tall trees by the water. Inside they are luxurious. Mine has wide windows on to a vast bend of the river, crisp beds under frilly nets, and a claw-foot bath with a view to die for. At night, hippos grunt in the shallows as I eat dinner on a raft on the river, the white linen and rare grilled steak lit only by glittering candles and stars overhead.
It's a far cry from Livingstone's experiences. To get closer to his era, I head up-country next day. A rattling 12-seat Cessna flies me to Mfue, gateway to one of Africa's finest game parks, South Luangwa. We soar above endless tracts of forest, marked only by the brown snakes of big rivers. Driving from the tiny airstrip to the park, I pass fields of maize plants and banana palms, between villages of mud and thatch where families gather in beaten-earth yards and mothers cook over open fires. How much out here has changed?
"David Livingstone crossed the Luangwa River just north of here," says Adrian Carr, stabbing a finger at the map that spills from his first edition of The Last Journals Of David Livingstone. We're sitting in his house on the edge of the park and he's showing me a book from 1874. On its red cover is a gold illustration of porters carrying the doctor across a swamp. "I know that place. There aren't any roads up there, but local people still use it to cross the river."
He pauses, a big, soft-spoken man in khaki shorts and shirt who has spent a lifetime guiding and hunting out here. "Can you imagine what it was like when Livingstone came through? The only white man for a thousand miles? He must have been so tough."
Toughness is a virtue still valued by men like Adrian, one of the last of the breed who made African safaris famous. His father, Norman Carr, invented the walking safari, back in the 1950s, and opened up Zambia for tourism. Black and white photos of the old man grace the walls of Adrian's game lodge nearby, where I will be staying tonight. They mostly show Norman with two tame lions at his side.
I drive into Kapani Lodge through a gateway roofed with reeds. On the road I have already seen three elephants. The lodge is built like a colonial estate, or perhaps the kind of mission station that Livingstone dreamed of founding. Its handsome cottages of ochre and thatch face a lake where hippos snort among flowers. Gazelles graze the banks. An open-walled drawing room has horns on the wall and skins on the floor.
I check in my bags and meet my guide, Shadreck Nkhoma. We hop in his 4x4 and roar off to the park. On a bridge across the Luangwa there are baboons on patrol and a 15ft crocodile in the water. The park itself is a lovely rolling landscape of tall green grasses and spiky mopane woodlands. A cloud of impalas drift down a slope to a waterhole where zebras swish their tails. In a grove of thorn trees, four giraffes stretch up to feed. This is Africa before the modern world. In the distance I hear the coughing of lions.
Rounding a bend, we catch a flash of yellow in a tree. Shadreck hits the brakes. The yellow has black spots. I raise my binoculars and stare into the eyes of a young male leopard. He flexes his paws and glances away.
"My family lived here before it was a park," says Shadreck, as we drive off. I ask how far the sense of history goes out here. "I know back to my great-grandfather," he muses. "His family came from Batoka, towards the falls. They came to this side of the river and lived the old way – in round mud houses with roofs made of grass, hunting and fishing." The sunset is a blaze of purple and gold. "Then the park came and they moved out to the village."
The village is Mfue, and next morning I ask Shadreck to show me around. We wander through the wooden stalls of the market and the concrete cabins of the hardware stores, and then we see a church. "That's my church," he beams and ushers me inside.
St Agnes Church is a redbrick box with glassless windows and a roof of tin. The elders shake my hand with warmth and surprise. "And this is our teacher, Edwin," says Shadreck with a grin. Edwin Chupa passes me a Bible. I cannot understand its words. "This is in our language," he smiles, and reads aloud the creation of the world in Nyanja. It's a lilting, soft language, making the ancient words anew for Africa. His voice rolls round the bare brick walls.
When he stops, I ask what he thinks of the missionaries like David Livingstone who came out here. His old eyes shine. "They brought us the light. They did not know it at the time, but they did. Now we have Christianity, roads, medicines." He touches my arm. "Because of them, we are standing here now, you and me, understanding one another."
Jonathan Lorie travelled with Expert Africa (020-8232 9777; expertafrica.com) which offers a week on safari in South Luangwa and two nights at the Victoria Falls from £3,521 per person, based on two people sharing, including flights from Heathrow with British Airways, transfers, meals and activities. BA (0844 4930787; ba.com/Lusaka) flies from Heathrow to Lusaka three times a week, with returns from £793.
Livingstone town is celebrating the Livingstone bicentenary with a range of events all year, including a cultural festival, sports and an international conference. ( livingstone2013.com).
The "Dr Livingstone, I Presume?" exhibition is at the National Museum of Scotland (0300 123 6789; nms.ac.uk) in Edinburgh until 7 April. Admission is free.
Explorer John Blashford-Snell is giving a lecture on Livingstone at the Royal Geographical Society in London on 28 March to raise funds for restoring the memorial at Chitambo village in Zambia, where Livingstone died. To order tickets, which cost £20, contact firstname.lastname@example.org or call 01747 853353.