 In 1871, the 27-year-old Rimsky-Korsakov became Professor of Practical Composition and Instrumentation (orchestration) at the Saint Petersburg Conservatory, as well as leader of the Orchestra Class.He retained his position in active naval service, and taught his classes in uniform (military officers in Russia were required to wear their uniforms every day, as they were considered to be always on duty).Rimsky-Korsakov explained in his memoirs that Mikhaíl Azanchevsky had taken over that year as director of the Conservatory, and wanting new blood to freshen up teaching in those subjects, had offered to pay generously for Rimsky-Korsakov's services.