In 1935, the writer Graham Greene set off on a journey through Sierra Leone and Liberia. In his book Journey without Maps, Greene asked what were the Europeans doing there? What did the slogans about civilising the natives actually mean? Humphrey Hawksley has been there to retrace Graham Greene's journey.
Shortly after dark as the solitary stilted "devil dancer" walked back into the Liberian forest, we headed off, but soon found the road blocked and in the darkness it was difficult to see why.
Humphrey encounters a number of trucks that fell foul of Liberia's roads
My torch beam picked up piles of bananas on the side of the road. I call it a road, but it was more like a farm track.
I then saw sacks of rice, a huddle of people - maybe 20 or 30 - they were passengers from a blue flatbed truck that was skewed across the route, its front wheels trapped in a ditch.
I heard what I thought was a baby's cry and ran forward only to find that four bleating goats were part of the truck's cargo. They were strapped onto the side, hanging and wrapped in brown cotton sheeting.
"We'll have to return to the village," I muttered to my Liberian driver, Mickey.
"No, we'll fix it," he said. "The chief back in the village is happy because we gave him some dash. So the devil is happy. So soon we'll go."
Dash is an old word for gift that the writer Graham Greene handed out to village chiefs when he walked through Liberia in 1935. I was tracing his route to see how much had changed.
Today, disease is still rampant, although the yellow fever of Greene's day has been overtaken by Aids. Pot-bellied children run around villages that are controlled by paramount chiefs. Christian missionaries still run much of the health service.
Built by missionaries, churches like Ganta's echo the European style
That morning, I had stood outside a small, stone church - such as you would find in any English village - at the entrance to the United Methodist Mission in the town of Ganta.
It was far in the northern interior of Liberia, and in Greene's day the inadequate map had simply marked the area as being inhabited by cannibal tribes.
Greene had stayed at this mission station as a guest of a Dr Harley who had built the church, set up a clinic and was an expert in the secret societies and spiritual ways of the devil that Mickey and I had just been discussing with the village chief.
One of Dr Harley's successors was Sue Porter, a quietly spoken and thoughtful American missionary nurse, who explained that many Liberians felt they had one foot in the bush and one in the modern world. And it was the same with their belief in God.
"When you talk about spiritual power here, it's about the power or an ability to do something whether it is good or bad," she said as we sat in the shade of a tree in the mission school grounds.
"Our Western culture doesn't allow us to see it as a dual-sided figure."
"It's our bush society," said Victor, the Liberian mission hospital administrator.
"The secret societies are meant to make you a good citizen, so the devil reminds you that if you are bad you can be punished."
Mickey and I had gone on to the village of Zorgorwee, where a "devil dancer" was to be performing at dusk.
The village chief, dressed in a bright yellow and brown robe, said he was too hungry to speak to me, until Mickey gave him some dash - a packet of biscuits from our car. Then the chief summoned a translator.
"My name is Jacob Kermon," he said in a booming voice that carried above the sound of singing and drums heralding the arrival of the devil. "And Jesus Christ is my personal saviour."
"Then, why are we here worshipping the devil?" I asked, slightly confused.
"When the devil comes out people feel good," he said. "He brings happiness and reconciliation within the community."
As the sun dropped and villagers lit fires, a stilted dancer walked in from the forest.
Humphrey danced with a devil in Zorgorwee
He stood six metres high. His face was covered with a black mask, his head rimmed with shells. He was dressed in orange pyjamas, his hands sealed within the cotton.
One by one the devil plucked us from the crowd.
I had to stretch up my hands to hold his, staring through wood smoke at the mask and on to a star-filled sky, as he twirled me round and round.
"In the Christian world," wrote Greene, "we have grown accustomed to the idea of a spiritual war, of God and Satan."
But, he added, in this supernatural world there was "neither good nor evil", simply power, a concept that was beyond our "sympathetic comprehension."
But it was not beyond that of Mickey, my driver.
He was a wiry, powerful, young man, expert in making things work when they should not.
He had already used soapy water to replace leaking brake fluid and found petrol hidden in mayonnaise jars in a town where we were told it had run out.
Now he stalked around the hapless flatbed truck, speaking softly to some people, raising his voice to others.
Tree branches went under the wheels. Men lined up to push. The driver waited for a cue, which was delayed while the bleating goats were unhooked from the side.
Then with a heave, the wheels spun and caught. The truck lurched, and to much cheering, it bounced back onto the road.
Mickey gave me a knowing look. "As the chief told us," he said, "if you dance with the devil, the devil will be nice to you."
Crossing Continents: Journey without Maps is broadcast on BBC Radio 4 on Thursday, 30 July 2009 at 1100 BST and repeated on Monday, 3 August at 2030 BST.
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