After five million words, the end of the road for Cormac's typewriter

Pulitzer-winning novelist finally gives up on the machine that has served him throughout his literary career

The only virus likely to have attacked the keyboard of Cormac McCarthy, the American writer whose books include No Country for Old Men and The Road, is of the literary genius variety. Aficionados would be forgiven for hoping his talent is infectious. Lean in close to the ancient space bar and worn-out shift buttons, and maybe you will catch it and win a Pulitzer Prize just like him.

The tool of Mr McCarthy's trade is not a computer or laptop that can be felled by electronic corruption, but a plain old typewriter. He has been tapping away for more than four decades on the same trusty model – an Olivetti Lettera 32 – which only now has clapped out on him.

But rather than junk so intimate a friend, McCarthy is putting it up for auction. Interested parties should contact Christie's in New York, where it is due to go under the hammer this Friday. It is expected to attract as much as $20,000 (£12,000) – not a bad return, considering McCarthy bought it for $50 (£30) in a pawn shop back in 1963.

But the stories it could tell – and, indeed, has told. McCarthy, talking to The New York Times from Santa Fe, New Mexico, where he spends most of his time, estimates that over the years he and the Olivetti have together pushed out more than 12 novels, two plays, several screenplays and untold numbers of letters and flotsam. And three unpublished books, too.

"It has never been serviced or cleaned other than blowing out the dust with a service station hose," the author explains in a note that will accompany the machine at auction. "I have typed on this typewriter every book I have written including three not published. Including all drafts and correspondence I would put this at about 5 million words over a period of 50 years."

"When I grasped that some of the most complex, almost otherworldly fiction of the postwar era was composed on such a simple, functional, frail-looking machine, it conferred a sort of talismanic quality to Cormac's typewriter," Glenn Horowitz, a rare-book dealer who has arranged the auction on McCarthy's behalf, told the Times. "It's as if Mount Rushmore was carved with a Swiss Army knife."

The proceeds from the sale are to go to the Santa Fe Institute, a charitable scientific research organisation outside Sante Fe where McCarthy does most of his writing.

What happened to the Olivetti that consigned it to a belated retirement, we don't yet know. But it is likely that rather than attempting to revive it, any prospective buyer will simply marvel at it. Also indented on its roller are the words that went into other McCormack bestsellers, including All the Pretty Horses and The Crossing. His Pulitzer was awarded in 2007 for The Road.

If anyone is determined enough to have it fixed, it seems that the ribbons for this model of the once-popular Lettera can still be found, for roughly $10 a spool. It was one of the first typewriters with mechanical sensors that reversed the ribbon once it had reached its end, thereby doubling its lifespan.

Not that any of this will make sense to today's generation of literary students, for whom an Olivetti may as well be a quill pen. Is McCarthy seizing the opportunity to discover the marvels of word processing on a computer? He is not. A friend has already found him another portable Olivetti. This time it cost only $11.

Habits of a lifetime: Writers' ideosyncracies

* George Bernard Shaw wrote many of his major works in a shed at the bottom of his garden in Hertfordshire. It was fitted to a circular track so it could be moved around to improve the light.

* Jack Kerouac typed his 1951 work On the Road on what he called "the scroll", a continuous, 120ft-long scroll of tracing paper sheets that he cut to size and taped together.

* Marcel Proust wrote all seven volumes of his epic A la recherché du temps perdu (In Search of Lost Time) in a cork-lined room in Paris. Tortured by allergies, Proust wanted a space that would shelter him from dust and drafts.

* Veteran novelist and columnist Keith Waterhouse, who died earlier this year, always used the same typewriter. He once mentioned he was finding it hard to get more ribbons, and The Daily Mail office received enough to last a lifetime.