Apt: The town of Opatow in central Poland gave its name to the Apt Hasidic dynasty, founded by Rabbi Avraham Yehoshu‘a Heshel, known as the “Lover of Israel” (Ohev Yisrael) after his hasidic homilies of the same name. He was also the namesake and forebear of the renowned Polish-born American scholar and activist Rabbi Abraham Joshua Heschel, who taught just up the street at the Jewish Theological Seminary.I found the following owner’s mark in R. Joel Sirkes’ שו”ת בית חדש החדשות, Responsa Bayit Hadash HaHadashot, Koretz 1785 (call number B893.1NL Si79):
Jewish Studies @CUL