Madeleine Stern was a renowned antiquarian book dealer, but her most important discovery was not a book at all. It was a series of lurid stories, all published in gaudy popular journals, all written under a pseudonym, all by New England's fresh and hearty Louisa May Alcott.

During her lifetime, the last vestiges of Victorianism gave way to modernism, to pop, to postmodernism. Cars replaced horses. Television, computers, cell phones, the Internet all came to conquer the world she grew up in. She traveled to Europe just before World War II and after. Revolutions came, and revolutions went. But Stern barely registered these changes, for she was creating her own revolution.

Stern invented herself. She was the Gatsby of pedants. A fervent but utterly apolitical feminist in a world where feminists were bluestockings and then bra burners; a devoted scholar with a thriving business in a world where scholars were either academics or independently wealthy gentlemen; an innovative and revered entrepreneur in the leather-armchair world of gentlemen antiquarian book dealers; unmarried in a world where women were wives, Stern lived in a universe in which it was not possible to live the way she wanted to. She simply ignored that impossibility, created her own universe and, in a small but exquisite way, changed the world.

Stern saw herself quite explicitly as a "pioneer," and perhaps that gentler, old-fashioned word better describes the tenor of her life and her achievements than "revolutionary" does. Raised as the pampered daughter of well-off German Jews long established in America, she attended Barnard and met Leona Rostenberg, the person who was to become her partner in the rare-books business and in life. After reading Stern's two books of memoirs, it is difficult to think of her without Rostenberg—perhaps because even in this most individual of all genres, the autobiography, the two women were together. They wrote "Bookends" and "Old Books, Rare Friends" as joint ventures. They were firm and emphatic that what they shared was love, and that their love was platonic, but as the titles suggest, they saw their lives as one. "Our lives are our legacy, and it is a legacy dominated by the first-person plural."

Stern and Rostenberg wrote biographies, scholarly studies and histories—both together and separately—but their greatest art was not writing. (The style, both stiff and florid, has the static, decorative quality of good wallpaper rather than of literature.) They worshiped books, and both had an encyclopedic knowledge that allowed them to discover rare volumes others had overlooked. But their art was not reading, or even "sleuthing," as they sometimes called their literary digging. The two ladies, living and working out of Rostenberg's childhood house in the Bronx, were like great hip-hop D.J.'s, energetic, imaginative artists of sampling. The most personal and inspired art they created were catalogs—brilliant, fascinating, scholarly, witty, inspiring, utterly original catalogs of old and rare books. They saw connections that others missed.

Instead of just listing the books they were selling, they had the vision to see the patterns their stock formed. When the 400^th anniversary of Shakespeare's birth was celebrated and they had no rare Shakespeare volumes, they designed a catalog of books published in each year of Shakespeare's life. Every book was captioned with a quotation from a Shakespeare play. "Under the date 1566, and under the caption 'O brave new world,' we offered Sir Thomas More's Latin works, including the 'Utopia'; under the date 1587, we described an oration on the death of Francesco de Medici, headed with the quotation 'Good-night, sweet prince,'" they wrote in "Old Books, Rare Friends."

What brought these remarkable women to the attention of the world outside rare-book collectors—there has even been a musical based on their lives—was their joint discovery regarding Louisa May Alcott. Scholars had long suspected that the potboiler blood-and-thunder stories written by Jo March in "Little Women" reflected real-life sensational stories written by Alcott in her constant early attempts to earn money for her bankrupt family. But no one had ever identified these stories. Until Stern and Rostenberg got on the case. It was Rostenberg who discovered Alcott's pseudonym (A.M. Barnard), giving a war whoop in a silent Harvard library where the two sat doing their research side by side. And it was Stern who uncovered many of the stories after an exhaustive search through the trashy periodicals of the day like The Flag of Our Union and Frank Leslie's Illustrated Newspaper. Stern eventually edited three editions of these stories of murder, adultery and incest written by pink-cheeked America's most beloved 19^th-century authoress.

In one of their memoirs, they wrote: "We still end each other's sentences. Together we look to the future—to our next find, to our next book, to our next adventure." The authors were 84 and 87. Leona Rostenberg, the elder, died in 2005 at 96. And now her faithful friend is gone, too. But they have left a legacy, and it is more than their discoveries and innovations in their antiquarian book dealings. It is more even than their important discoveries and scholarship regarding printing, early American literature and Louisa May Alcott. They have, as they predicted, left behind perhaps the rarest legacy of all: that of the first-person plural.