Philip Hoare’s books include Leviathan and Albert & the Whale (both 4th Estate).

Francis Bacon gave me the glad eye once. He was boarding the bus at South Kensington, bound for Soho, I guess. His face was florid, his look sharp. His friend, the artist Michael Wishart, said Bacon had the eye of a bird of prey. But I didn’t feel predated that day, just honoured. His eye, looking back, unblinking. The artist of the nuclear age. A starry hunter like Orion; but also the prey.

During his childhood in Ireland, Bacon had pored over books of big game animals, fascinated by the lives and deaths frozen in photographic plates. Later, his family would migrate to Africa. His elder brother Harley moved to South Africa and then Northern Rhodesia, dying of tetanus in 1929. By 1950, his sisters and mother had moved to South Africa. These were still colonial zones as far as white people were concerned, with dark relationships with the West.

On his own subsequent visits, Bacon would see the place, and especially its animals, the way he saw everything else, through his mythos of sex and death. On 4 January 1951, Bacon sailed from Southampton to South Africa. We don’t know what he saw in the Kruger National Park, where one may turn a corner and be confronted by willowy giraffes with the poise of supermodels, or lions after slumber stretching their legs like athletes, or crouching hyaenas like spotted gargoyles. As we project our qualities on other species, knowing so little as we do of their own, so they often decline to perform.

Bacon would later observe: “People have these ideas about good and bad… the jackal is bad. Everyone knows that wildlife has evolved over millions of years, slowly, naturally, and yet we seem to want to apply almost puritanical adjectives to animals as individuals, judging them in our world, never ourselves in theirs.” That trip, the animals seemed to be concealing, rather than revealing themselves. Nonetheless, Bacon took many photographs, and declared that he wanted his paintings to have “the same immediate effect of an animal after the kill”.

In the spring of 1952, Bacon returned to Africa with a new lover, Peter Lacy, a pianist and former RAF pilot with sadomasochistic tastes. Bacon acquired 12 whips of rhino hide, with which Lacy would beat him. Again, details of what Bacon saw of the other wildlife are scarce. But back in London, animals began to appear in his work, as if they’d been there all along.

In his exhibition at the Hanover Gallery that winter, he showed a painting of an elephant crossing a river. Set in a dark landscape that seems to dwarf it, the giant wades through oil-black water. The spirit of the image makes it startlingly modern; it might have been painted by Peter Doig. The elephant trails its own extinction, laden with the paradox of the anthropocentric phrase, ‘Big Game’. Just as the expression ‘livestock’ implies ‘soon-to-be-deadstock’, so the big game were doomed by their name. They stand there stilled by their fate: to be killed, replaced, then killed again.

Bacon drew this ur-animal not from life, but from a book that celebrated this imperial pursuit of death. Marius Maxwell’s Stalking Big Game with a Camera in Equatorial Africa (1924) is shot through with the memory of violence. Maxwell photographs elephants, then kills them. “Picking up my 0.600 bore, I emptied both barrels in rapid succession on the biggest bull. Bewildered at first, the other elephants crowded aimlessly round the carcass of their fallen leader… until they finally moved away in sedate and stately fashion.”

In another canvas, Bacon painted a rhinoceros in an open landscape; he was haunted by the veldts and forests of Africa, he said. “I felt and memorised the excitement of seeing the animals move through long grass.” But something about the rhino dissatisfied him. His beast was crumpled, collapsed, abased. So, like a hunter, he took his Stanley knife to it, in an augury of contemporary rhinos sacrificed to furnish aphrodisiacs, a death for love. All that remains is an indistinct reproduction of the painting, a kind of grey rival to Albrecht Dürer’s clanking immortal woodcut of 1515. And just as Dürer saw only sketches sent to him of the rhino, so Bacon chose to paint the animal from a photograph in his London studio; it was its component parts that he needed.

When he asked David Sylvester to pose for him, the critic was surprised to find Bacon ignoring him and peering at a photo of a rhino instead; the artist said the animal’s skin intrigued him: “I didn’t especially think that he looked like a rhino. The movements of the body of this rhino gave me suggestions of movements – about his face – so that I could dislocate his face in a way…”

Animal and human were becoming blurred in Bacon’s visceral canvases. He began to paint images of wild dogs that appear like prowlers in the Soho gutters. These ghostly beasts are no pets, and they show no emotional connection with us, unless it is despair. That’s where Bacon’s animals find their fugitive power, in their shadowy in-betweenness. Humans, as Bacon said, are most obsessed with themselves. And so his mysterious evocations of chimpanzees, baboons and owls were in fact drawn in London Zoo; zoologist Desmond Morris declined to tell Bacon that the screaming primate he had painted was actually yawning. What Bacon saw or did not see, and what we then see or do not see, betrays our incomprehension, “the narrow abyss” of ignorance that the artist-writer John Berger saw between ourselves and other species.

Seeing Bacon’s 1952 exhibition at the Hanover Gallery, painter John Minton proclaimed it was “all about Bacon dogs. Dogs, shitty South African dogs, dogs with foul breath”. But critic John Russell saw a vision of “an imagined Africa as mystical as Shakespeare’s Italy”, one which was freighted with “the haunting power of private emotion”.

In 1967, Bacon met the handsomest man he had ever seen. Peter Beard was an adventurer and photographer, born in New York. With his square jaw and thick hair, he became Bacon’s perfectible other – muse, avatar, friend. Equally, Beard told the artist’s biographer Dan Farson that Bacon was the most important thing in his life. When they first met, Bacon informed Beard he owned his book, The End of the Game, a delayed, accusatory response to Maxwell and his kin. Its death-in-life images transfixed Bacon, a fatal tumble of tusks and ribs, of African people bearing witness to foreign hunters. The animal skins which Bacon had used as art deco furnishings in his youth had become shrouds over bones. Beard’s photographs are a bitter, beautiful reproach; Bacon transforms their darkness into something yet darker. He would paint some nine portraits of Beard, as if to possess his friend’s own animal grace.

Those paintings also echoed with three more trips Bacon made in the late 1960s to southern Africa, to see his ailing mother. Visiting his sister Ianthe in what was then known as Rhodesia, he was taken out hunting. An eland was shot, and Bacon helped skin and butcher the animal. He said he was fascinated by the colour. But he also saw these scenes through one of the books that, as he told Sylvester in 1966, he had almost memorised by heart: Conrad’s Heart of Darkness, which he called a great “isolated peak of literature”. (The betrayal and execution of the homosexual Roger Casement, Bacon’s fellow Anglo-Irishman and part inspiration for Conrad’s story, must have also resonated.)

The powerful effect of Conrad’s portrayal of murderous colonial horror was one he shared with Beard, to the extent that Bacon painted his friend – after he had briefly been imprisoned in Kenya for assaulting a poacher – as a kind of Colonel Kurtz figure from the story, an imperialist driven insane by his own depredations. Beard’s shaved head appears in Triptych (1976), as do vultures he photographed, here pecking on human flesh; and in response, in a diptych he sent to Bacon, Beard collaged a gilt-like image of a dead elephant calf over a photograph of himself, paired with a scene of warthogs and giraffes (above).

The toy-like pachyderm is set against the half-naked beauty of Beard-as-Ariel, laying a tribute before Bacon-as-Prospero. Four years earlier, in 1972, in a taped conversation, Bacon and Beard discussed those dead elephants. The world was catching up with Beard the eco-prophet; it was still coming to terms with the dark visions of Bacon’s art. Their dialogue reads like a play by Beckett.

“We are not natural,” Beard said to his friend. “We have gone so far from natural.” Bacon’s own nature had been outlawed for all but five years of his life. “Well, there’s nobody more unnatural than I am myself,” he told Beard, “and after all I’ve worked on myself to be as unnatural as possible in a sense.”

“It’s the shape and the movement of animals which really absorb and interest me,” Bacon said. “And I link their movement with human movement… the organism of movement in itself…” He told Beard how his first interest in animals came from Eadweard Muybridge’s book on animals in motion, and from Maxwell’s book. “I found those tremendously exciting… They set up a whole mechanism of images for me which very often hadn’t anything to do with the photograph I was looking at, but they were like a trigger which released something with me, you can call it some kind of instinctive drive or reaction, and for that reason animals have always fascinated me and especially photographs of animals, because I find with me, it sets up a sort of underground train of imagery.”

“Are there any other things which you see as beautiful things,” Beard asked him, looking around at the debris of the artist’s room, “such as a discarded newspapers changing colour in the sunlight?”

“Bones and carcasses that have been in the sea or sun and sand for a long time and have changed into other things,” Bacon replied. “There is a kind of beauty in that – a kind of magic.”

He picked up one of the scraps. “I don’t know what this image here is. I was actually looking at a photograph of some birds diving into the sea, and this thing came out of it – this kind of double image, I don’t really know what it is.”

“‘Do you think those dead elephants have an aesthetic quality to them?’ Beard asked.

"No, I don’t,” Bacon replied. “You can say that there are… beautiful elephants, beautiful people but I don’t think that’s the same thing as aesthetic. Aesthetic is even more artificial…”

“Another kind of beauty,” Beard said.

“For me it’s in the state in which I see it in the photograph”, Bacon said. “It’s a trigger. It’s a release action, I mean, it releases one’s sensibility… After all, the mind tends always to be making out of chaos, patterns… the chaos of a decomposing elephant…”

It was as if both men knew it was already too late. That the balance of both human and animal life on the planet faced irrevocable threats. Twenty years later, after Bacon’s death in 1992, hundreds of Beard’s photographs were found scattered on the floor of Bacon’s studio. It was a silent, spectral site; a “deeply ordered chaos” as the artist said. Bacon’s animals are not ironical or emblematic. They stand across the abyss, looking back at us.

“I’m not here to preach anything,” Bacon told Beard. “I work as near to my instinct as I possibly can. It’s all I can do”. After all, he was only an animal himself.

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