NEW YORK (AFP).- Six letters written by US novelist Harper Lee flopped at auction Friday despite feverish interest in the publication of her second novel, set for release next month.

The typed letters sent from 1956-1961 to a close friend, New York architect Harold Caufield, shine a rare light into the personal thoughts of one of America's most reclusive but celebrated authors.

Christie's had valued the letters at $150,000 to $250,000, but there was no buyer and bidding stopped at $90,000, a spokeswoman for the auction house told AFP.

Lee's only published novel to date, the best-selling masterpiece "To Kill a Mockingbird," won the Pulitzer Prize for its tale of racial injustice in the Depression-era South.

Published in 1960, it has become standard reading in American classrooms and has been translated into more than 40 languages, as well as adapted into an Oscar-winning film starring Gregory Peck.

Lee, 89, lives as a recluse and it is exceptionally rare for her private writings to come onto the market.

Four of the letters were written before "Mockingbird" was published and detail her thoughts in caring for her adored father and the strains of life in her hometown of Monroeville, Alabama.

In 1960, she wrote in raptures about the dazzling success of her novel -- "We were surprised, stunned and dazed by the Princeton Review," she said.

In one letter from 1956, she expresses her "longing" to return to writing in New York. 

"I simply can't work here. Genius overcomes all obstacles, etc., and this is no excuse," she wrote.

She also has choice words for society in Monroeville.

"Sitting and listening to people you went to school with is excruciating for an hour -- to hear the same conversation day in and day out is better than the Chinese torture method," she wrote.

"It's enough to make you give up."

HarperCollins is to publish Lee's second novel, "Go Set a Watchman," on July 14.

The book is already a best-seller at online retail giant Amazon, where the 304-page hardback is available for pre-order.

The announcement earlier this year of its release set the literary world alight and delighted Lee's millions of fans, despite sparking speculation about whether she was of sound mind.

She wrote the manuscript in the mid-1950s and it was only recently re-discovered by her lawyer.

Deaf and suffering from poor eyesight, Lee lives in a nursing home.


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