Moshe ben Maimon (Maimonides). Mishneh Torah. Part III: Zemanim.

<<AUTOGRAPH UNPUBLISHED NOTES BY THE ROGATCHOVER GAON ON MAIMONIDES.>> The Rogatchover (1858-1936) was one of the greatest Talmudic geniuses of the 20th century who had a remarkable ability for penetrating, original, analytic conceptualizations throughout Rabbinics. This volume has many lengthy, interesting unpublished marginal notes in his hand. They are not included in his Tzafnath Pane’ach on the Rambam’s Mishneh Torah. These marginal notes are important as they contain far more explanatory text than the terse references that was generally the Gaon’s style. For example, see p. 9 and p. 166 where the Rogatchover discusses the form of expertise required of a doctor to allow the performance of work for the benefit of the sick on Sabbath, or to allow an ill person to eat on Yom Kippur. Although autograph letters by the Rogatchover are extant, personal books of his are almost unheard of as his library was destroyed by the ravages of the Holocaus