(Rosh Yeshiva and Rabbi of Slobodka and Hebron, 1866-1933). Letter Signed and stamped, written in Hebrew on letterhead to Rabbi Tobias Geffen.

A student of the famed Volozhin Yeshiva, R. Moshe Mordechai Epstein, founded the Kneseth Israel yeshiva in Slabodka, along with one of his teachers, the Mussar exponent, R. Itzele Peterburger. The Slabodka yeshiva, which he headed in Lithuania, and then in Eretz Israel when a branch was opened there in 1924, was where many influential rabbis of the post-Holocaust era had their beginnings. A native of Kovno, Rabbi Tobias Geffen (1870-1970) held a pulpit in Atlanta, Georgia from 1910 until his death. More than just the rabbi of a shul in Atlanta, he was deeply involved in all the multifarious sides of Jewish life in America. A distinguished Torah scholar, he is best known for something which came about as a quirk of geography. Living in Atlanta, the home of Coca Cola, Rabbi Geffen regularly fielded inquiries from rabbis across the United States as to the kashruth of the soda for Passover. Coca Cola’s ingredients were a closely guarded trade secret which had been made a part of the brand’s legend. Rabbi Geffen asked the company to reveal the ingredients to him so that he could ascertain it’s kashruth. Surprisingly, they agreed. With one recommendation for an ingredient adjustment, Rabbi Geffen wrote a responsum showing that Coca Cola was kosher for Passover and all year round. See https://www.jewishvirtuallibrary.org/the-kashering-of-coca-cola.