Some years ago, I rode a bus north from Rio to Bahia, a journey of a thousand long miles and thirty long hours, through blue mountains, dusty air and the Sertão, that region menaced by poverty and afflicted by droughts that last years. I was reading Moritz Thomsen’s account of the same journey, made in 1978, which was published under the title The Saddest Pleasure. I saw Brazil through Thomsen’s eyes as well as my own, as though I were wearing two pairs of spectacles. To use George Orwell’s words when he first came across Henry Miller, ‘He knows all about me … he wrote this specially for me.’

The book is part travel writing, part memoir and part a polemic on behalf of the poor. I found it a perfect combination, and that genre, or non-genre, has attracted and influenced me ever since. Thomsen combines insight, mood and sensibility with vivid topographical descriptions. No one has ever conjured the sweet night air of the tropics like him.

He was sixty-three when he boarded that bus in Rio, in many ways a broken man. He had flown combat missions in the Second World War and then farmed in California, where he went painfully broke. His marriage had failed. He had been ill. After serving for four years in the Peace Corps in Ecuador, he bought a large tract of land there, near Esmeraldas, with an Ecuadorian partner, Ramón; he calls the decade he spent there ‘the last movement of the somewhat banal, hopelessly romantic symphony that was my life’ (the sentence is characteristic of Thomsen’s elegiac melancholy). His motivation in part was to enable Ramón to ‘reach his full potential’. Ramón eventually kicked him off the farm.

The first two chapters of the second part of The Saddest Pleasure unfurl in Rio. Thomsen walks miles and speaks to few souls. His prose is peopled with whores and syphilitic drunks. On the bus to Bahia, Thomsen falls ill and the writing becomes feverish. In Bahia he sees garbage-choked streets that plunge down hillsides and ‘little shoe-shine boys twisted with hunger’. There he meets the writer João Ubaldo Ribeiro; in this unsatisfactory encounter, much whiskey is drunk.

From Bahia he goes on to Recife (‘this sailor’s hell invented by Hogarth or Gissing’), Natal, Fortaleza and Belém, its streets ‘lined on both sides with enormous mangos’. But by then Thomsen is anticipating his first, much-longed-for glimpse of the Amazon. He marvels at ‘that watery, half-drowned world that held the secret, the mystery of man’s essential inconsequentiality’.

The book, published in 1990, is a threnody for Brazil, and for the lost hopes of life itself – Thomsen’s, mine, yours, everybody’s. The memoir component of The Saddest Pleasure circles mostly around Thomsen’s late father, a wealthy bigot whom the author despised. Yet Thomsen needed the family money. His father accused him of being a communist. He realises, after the old man is gone, that his life has been nothing but rebellion. The Saddest Pleasure is a fine contribution to the literature of men writing about their fathers (I would like to see an anthology on that topic).

The whole Brazilian trip ‘was a symbol of rejection, humiliation, and uselessness,’ Thomsen writes. Yet there are dabs of humour. An unfriendly bank clerk becomes ‘Deirdre of the Sorrows’ and the author has fun with his fellow passengers on the riverboat trip with which the book ends. They include three disagreeable French tourists, an English Baptist missionary, a constipated dog and a hulking Dutchman, with whom Thomsen discusses God at some length. This part of the book has lots of yeasty direct speech.

Thomsen sets off in this boat, two-thirds of the way through the book, for Manaus. Cruising down the Amazon, past jungle and farms, he threads flashbacks of his experiences in Ecuador into the riverine travel narrative. He and Ramón had bought a second farm and branched into cattle and Thomsen lived on it alone for two years, a shriving of sorts.

Thomsen wrote two other books before The Saddest Pleasure, but says he had never thought of himself as a writer. He had set down his words ‘in those predawn hours when the land lay still in darkness, or in days of heavy winter rains when the cattle huddled in the brush dumb with misery … I had always considered that all my passion was centred around farming.’

But what a writer he is. He taught me the value – no, the vital importance – of specificity. A smell of garlic through the window of a seedy hotel ‘so strong that one can almost see it’; the taste of ‘little swordfish with blue bones’; women standing in doorways silhouetted against candlelight. An emptied dude ranch that ‘suddenly seemed as dead as some animal with its throat cut’; fishing boats slicing ‘long slow lines across the water’. I experienced all of these things in Brazil and The Saddest Pleasure heightened my perceptions. I also glimpsed the contradictions that bothered Thomsen. Isn’t it hypocritical, he asks, to spend $16 on food in a French restaurant while pontificating on the agonising life of the poor?

His themes, alas, are as relevant as ever: economic destitution, corrupt policemen and politicians, racial tension, inequality, the ruination, by one means or another, of indigenous peoples. Thomsen often mentions loneliness and his fears for his sanity. He is a modest, vulnerable man. He writes about writers – mostly the usual suspects, Proust, Machado de Assis and so on, his top man being Conrad (‘when he is at his best no one comes near him’). The title of the book comes from a line in his friend Paul Theroux’s novel Picture Palace – ‘Travel is the saddest of the pleasures.’

There is a denouement, or redemption, of sorts, in the final chapter, which is called ‘The Joining of the Rivers’. For the first time, Thomsen can say out loud, ‘I am a writer’, and, also for the first time, he relives the traumatic last month on the farm. He feels changed.

‘I am living’, he said before the trip, ‘with the kind of emptiness that only death can fill.’ He died of cholera in Guayaquil in Ecuador in September 1991.