Author Margaret Mitchell, inset, wrote Gone

St. Louis ? Margaret Mitchell wrote one of the most popular American novels of all time when she published “Gone With the Wind” 75 years ago.

But she never followed up the Civil War drama with another story before she died in 1949, hit by a drunken driver as she and her husband walked to a movie theater.

Now a Missouri medical journal has unearthed a letter from Mitchell to a Kansas “horse and buggy” doctor in which she says she was too busy tending to her ailing father to attempt another book.

From her Atlanta home in September 1944, she wrote Dr. Arthur Hertzler of Halstead, Kan., complimenting him on his new “Ventures in Science of a Country Surgeon.” She also writes:

“I had intended to write you about the thyroid book, but my father died in June and I did not have time or the heart. He had been ill so long — six years in all, and the last three in the hospital. … When people ask why I have not written another book, I look at them in wonder, for how can one do creative work in a constant worry like this or when physical fatigue reaches the point of exhaustion every day. I hope that my own health will improve now that I do not have to bend over high hospital beds or fix pillows or lift or strain.”

A story about the doctor (whose files also held a letter from Albert Einstein) is published in the new issue of Missouri Medicine, the journal of the Missouri State Medical Association. The article is written by Drs. Jane F. Knapp and Robert D. Schremmer. Missouri Medicine is edited by Dr. John Hagan III.

Hertzler’s books included 20 medical textbooks and 1938’s best-selling “The Horse and Buggy Doctor.”

Mitchell won the Pulitzer Prize for “Gone With the Wind.” The New Georgia Encyclopedia speculates about the reason Mitchell never wrote another book:

“Possibly one of the reasons that Mitchell never wrote another novel was that she spent so much time working with her brother and her husband to protect the copyright of her book abroad. Up until the publication of ‘Gone With the Wind,’ international copyright laws were ambiguous and varied from country to country.

“With the outbreak of World War II (1941-45), she worked tirelessly for the American Red Cross, even outfitting a hospital ship.”