Question: Wilhelm von Lenz, was a Baltic German Russian official and writer, and was a friend of many mid-century Romantic composers, including Hector Berlioz, that died on which date, was a French Romantic composer, best known for his compositions "Symphonie fantastique" and "Grande messe des morts" (Requiem)?
Sentence (from "Mémoires (Berlioz)"): After distributing some copies to certain friends, they were put aside until Berlioz died.
Relevant evidence: No