Simply because she loved to read, Lotte Fields bequeathed $6 million to the New York Public Library after her death, the library announced on Wednesday.

Ms. Fields, a New Yorker who died last summer at 89, inherited her wealth from her husband’s family, who were wool merchants.

“One of her great joys was spending the weekend reading with her husband,” said Irwin Cantor, Ms. Fields’s executor, in a statement. “Her donation shows just how much Lotte loved books and how important she felt it was to support her fellow book lovers.”

Because Ms. Fields had been a modest – though regular – donor to the library in the past, Tony Marx, the library’s president, said the library was “astounded” by her bequest.

“But we are deeply honored to pick up her mantle and promote the joy of reading,” he added.

At Ms. Fields’ request, the library will evenly divide the funds between its branch library system and the Stephen A. Schwarzman Building on 42nd Street.