Ernest Hemingway, in Kenya, in 1952. Photograph by Earl Theisen/Getty

Ernest Hemingway was one of the great innovators in literary form. His apparent renunciation of stylistic flourishes—the absence of lyrical rhetoric, the spare sketching of context, the paring of narrative voice to short, stark strokes—was the style of no style, an aesthetic obsession so fanatical and so closely linked to Hemingway’s sense of personal bearing and way of life that it comes off, in retrospect, as an inverse dandyism. Hemingway’s way of writing was also inseparable from his physically vigorous subjects, such as war, hunting, fishing, and bullfighting—and, early on, his notion of literary achievement was agonistic. In Lillian Ross’s majestic Profile of Hemingway, published in The New Yorker, in 1950, he likened his fiction-writing to boxing—with Turgenev, Maupassant, and Stendhal.

Hemingway’s 1935 book “Green Hills of Africa,” which has just been republished by Scribner in a new and augmented edition, is a work of nonfiction. It’s not his first; his encyclopedic account of the world of bullfighting, “Death in the Afternoon,” was published in 1932. But that book is about bullfighting overall, occasionally adorned with references to Hemingway’s own experience. It’s not a narrative; it’s a history and an analysis sprinkled with anecdotes. In “Green Hills of Africa,” by contrast, Hemingway states his ambitions clearly in a brief foreword:

Unlike many novels, none of the characters or incidents in this book is imaginary. . . . The writer has attempted to write an absolutely true book to see whether the shape of a country and the pattern of a month’s action can, if truly presented, compete with a work of the imagination.

Hemingway began his writing career during a time of innovation in literary form, and had spent much time in Paris in the company of one of the great innovators, Gertrude Stein. He himself was, from the start, a master formalist, and the declaration of intent in “Green Hills of Africa” deserves to be taken literally. It is, in the purest sense, an experimental work of writing, composed on the subject of adventure and in the spirit of adventure, to put himself—and writing as such—to the test.

The writing is Hemingway’s account of a trip to East Africa that he undertook in late 1933 with his wife at the time, Pauline Pfeiffer, for the purpose of hunting big game, including rhinoceroses, kudu, and lions. The couple are accompanied by a friend (identified as Karl in the book); a professional hunter (or “white hunter”) called, in the book, both Pop and Mr. J. P.; and a changing group of native guides, trackers, and bearers, including men called M’Cola, Droopy, the Wanderobo-Masai, and one whom Hemingway nicknamed Garrick in deprecation of the man’s theatrical mannerisms, which irritated the author. (As for Pfeiffer, Hemingway identifies her, in the book, as P.O.M.—Poor Old Mama.)

There’s also another character who turns up by chance early on in the hunt, an Austrian named Kandisky, who joins the party briefly when his truck breaks down. Kandisky has a literary bent. He recognizes Hemingway’s name from poems that the author had published in the German review Der Querschnitt about a decade earlier (one of them was a crudely sarcastic attack on six "lady poets”), and he engages Hemingway in literary conversation, bringing up a name that will come back twice more in the course of the book: “Tell me what is Joyce like? I have not the money to buy it.” Kandisky means “Ulysses,” of course, which was published in 1922, in Paris, by Sylvia Beach, the founder of Shakespeare and Company, and which was banned on the grounds of obscenity both in the United States and Great Britain.

Joyce is the spirit that haunts “Green Hills of Africa,” both by name and by implication. In effect, the account of the hunt is also a manifesto of sorts, as when Kandisky further engages Hemingway in exactly the sort of literary theorizing that the author both distrusts and enjoys. Hemingway tears through the history of American literature and leaves only three survivors—Henry James, Stephen Crane, and Mark Twain. (This section is the source of Hemingway’s famous remark, “All modern American literature comes from one book by Mark Twain called Huckleberry Finn.”) The two men engage in a sharp page of stichomythia regarding Hemingway’s pleasure in writing, which Hemingway expands into a frank, visionary statement of ambition:

"The kind of writing that can be done. How far prose can be carried if anyone is serious enough and has luck. There is a fourth and fifth dimension that can be gotten."

"You believe it?"

"I know it."

"And if a writer can get this?"

"Then nothing else matters. It is more important than anything he can do. The chances are, of course, that he will fail. But there is a chance that he succeeds."

"But that is poetry you are talking about."

"No. It is much more difficult than poetry. It is a prose that has never been written. But it can be written, without tricks and without cheating."

“Green Hills of Africa” points toward those fourth and fifth dimensions. Hemingway’s aesthetic is also a matter of morality, based in the truth of first-person experience, tested by one’s own unsparingly high, self-critical standards. Throughout the book, Hemingway submits his hunting ability, his consideration toward others (the term that he reserves for himself at his most insensitive is a “four-letter man”—presumably, a shit), his modesty, his bravery, and his powers of perception to the test (which doesn't prevent him from flinging around some ugly racial epithets). That test comes in literary terms, in effect stopping the action with a grand series of asides and analyses which aren’t a matter of the narration of the hunt but a narration of what happens to be passing through Hemingway’s mind at a given moment. These asides are the very heart of the book.