Letter and six printing details connected to Rabbi Avraham Yitzchak HaCohen Kook and the early stages of the Mercaz HaRav Yeshiva: * A letter in stencil printing addressed to Rabbi Yudkowsky in Chigaco, regarding the provision of aid to the Mercaz HaRav Yeshiva. Signed with the handwritten signature of Rabbi Yaakov Moshe Charlap and the yeshiva’s Rabbis. [1] official paper leaf, 22×28 cm. * A board with a printed photograph of Rabbi Kook. New York, 1930’s. 19×14 cm. Underneath the photograph is an illustration of the Temple Mount and the Tower of David in colored lithographic printing. Below it is the verse “If I forget you Jerusalem” in Hebrew with its English translation. On the rear side, in Yiddish and English, is information about the support required for the Mercaz HaRav yeshiva’s upkeep. * New year’s greeting by the Mercaz HaTorah B’Eretz HaKodesh [The Center of Torah in the Holy Land]. A prospectus with a new year’s greeting from Rabbi Kook on behalf of the Mercaz HaRav yeshiva: “The Rosh Yeshiva and its sons…bless his honor that G-d will write and seal him for a good and joyful year…”. Jerusalem, 1929. Added to the blessing is a photograph of the 1929 class of the yeshiva’s students. Rare, not in the National Library. * Mercaz HaRav Yeshiva, HaYeshiva HaMercazit HaOlamit [the Central Universal Yeshiva]. A printed poster requesting financial assistance for the Mercaz HaRav yeshiva, with a photocopied letter from Rabbi Kook. Hebrew and Yiddish. 23×28 cm. * Pitzei Ohev. An article by Rabbi Avraham Yitzchak HaCohen Kook. Published by Histadrut Yerushalayim. Jerusalem, Solomon printing press [1921]. First edition. Rebuke about desecration of the Shabbat, eating non-kosher food and licentious behavior in the new settlement in Israel. 5 [1] pages, title-page cover, 15 cm. Fine condition. * Iggeret HaTahara, by Rabbi Avraham Yitzchak HaCohen Kook. Published by ‘Mercaz HaRav’ by Degel Yerushalayim. Jerusalem, Solomon printing press. [1921]. First edition. An important work about immersion in the mikveh. 77 pages, detached title-page cover, 13 cm. Fine condition. * Shir HaEmunah, by Rabbi Avraham Yitzchak HaCohen Kook, printed in pocket format, and dedication to the occasion of our great Rabbi’s return to our holy land from his long journey to America, Zion printing press, Jerusalem, 1924. Sizes and conditions vary, overall fine condition.