MARK IDELSON (d. 1942)
Born in Vilna to well-to-do parents. Throughout his youth, he was a member of the Bund. During WWI he was in Odessa. In 1919, he returned to Vilna as a teacher of technical subjects. Later he was an instructor of physics in the technical faculty of the ORT vocational school. His Yiddish terminology for physics and mathematics were issued in mimeographed form through the Vilna ORT technical faculty and were used for practical work. He was active leader, collector, and bibliophile for YIVO. In the Vilna ghetto he ran technical and Bundist youth programs. He died in the Vilna ghetto.
Sources: Sh. Katsherginski, Khurbm vilne (The Holocaust in Vilna) (New York, 1947); H. Avramovitsh, in Unzer shtime (Paris) (May 23-24, 1951).