This Eastern European subscription programme of the Boston Symphony Orchestra contained a substantial rarity, the dramatic Second Violin Concerto by the Czech composer Bohuslav Martinu. In fact the orchestra had given the work’s first performance with the violinist Mischa Elman, for whom it was written in 1943 while Martinu was in homesick exile in the US, a period which included a stint of teaching at the orchestra’s summer school in Tanglewood.