Theodor Seuss Geisel died in 1991. The LIFE Images Collection/Getty Images

In the early 1950s, a former ad man and modestly successful children's book author published a series of illustrated stories for children in magazines like Redbook. They were short, two-to-three page spreads with stamp-sized drawings and minimal coloring. He hoped to publish them in book form but another project gained steam.
In 1957, he published a book that became an immediate best seller, turning him into a global publishing phenomenon. By approaching learning to read as zany and fun instead of boring and dull, the book altered the children's literature landscape. His name was Theodor Seuss Geisel and the book was called "The Cat in the Hat." While some of the magazine stories eventually made it into a book during his lifetime, others never did.
Cathy Goldsmith, an executive for Random House, is the last remaining employee to have worked directly with Geisel. Noah Rabinowitz for The Wall Street Journal

On Sept. 9, Random House will publish "Horton and the Kwuggerbug and More Lost Stories," the second collection of Dr. Seuss's forgotten magazine work. The previous volume, "The Bippolo Seed and Other Lost Stories," reached No.1 on the New York Times best-seller list when it was released in 2011. Random House is betting even bigger on "Horton," with an extensive marketing campaign and a large first print-run of 250,000 copies. "It tickles me that a whole new generation will get to read and experience these characters, some new and some familiar," said 
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