BENJACOB, ISAAC (1801–1863), first modern Hebrew bibliographer. He was born near Vilna and spent most of his life in that city. After publishing original works and republishing several medieval writers, including Ḥovot ha-Levavot by *Baḥya ibn Paquda (with a commentary of his own), Benjacob published, with Abraham Dov *Lebensohn (Adam ha-Kohen), a 17-volume edition of the Hebrew Bible (1848–53). It included Rashi's commentary, Mendelssohn's German translation (in Hebrew script), a new commentary by Lebensohn as well as Benjacob's own Mikra'ei Kodesh, an abridged version of TikkunSoferim ("the scribes' emendations to the biblical text"). This edition helped spread Haskalah among Russian Jewry and was utilized not only for the study of Scriptures, but also for learning German. Benjacob then began his magnum opus of 20 years' duration, Oẓar ha-Sefarim (Vilna, 1880; repr. New York, 1965), one of the greatest bibliographic achievements in Hebrew literature. The work lists approximately 8,480 manuscripts and approximately 6,500 books published up to 1863, with a description of their contents. Benjacob also wrote a collection of epigrams, poems, and literary essays, Mikhtamim ve-Shirim Shonim (1842). His son jacob (1858–1926) was a merchant, banker, and Zionist. After first publishing his father's work Oẓar ha-Sefarim with the assistance of M. *Steinschneider (1877–80), he began expanding it, using new bibliographical methods but retaining its original chronological limit (1863). His son-in-law Moses *Schorr reported that the new edition contained 60,000 entries and comprised 12 volumes. Both Benjacob and Schorr tried unsuccessfully to have it published. The manuscript was lost during the Holocaust in Poland.
Benjacob, Oẓar, xxi–xxvii; B. Nathanson, Sefer ha-Zikhronot (1876), 112–5; Habermann, in: Yad la-Kore, 3 (1952/53), 1–6; Schorr, in: yivoBleter, 8 (1935), 138–46; idem, in: Soncino Blaetter (1927), 38–40; Waxman, Literature, index.
[Benzion Dinur (Dinaburg)]