Nat Wartels; Built Crown Publishing Empire

NEW YORK — Nat Wartels, the frugal, hard-working architect of the Crown publishing empire and numerous other book ventures, and considered the nation’s wealthiest book publisher, died Wednesday.

Wartels, 88, a Manhattan native who had worked in the book business since 1933, died of pneumonia in a New York City hospital.

Wartels and his partner, the late Robert Simon, built Crown into a successful company by buying publishers’ surplus books for as little as 5 or 10 cents a book, then reselling them to bookstores.

Wartels and Simon founded Crown in 1936. Wartels sold it to Random House in 1988 for an undisclosed amount.

His successes at Crown included the early 1980s publication of “Princess Daisy,” by Judith Krantz, which brought a record $3.2 million in paperback sales.