Flat Sousa and the staff of the Sousa Archives and Center for American Music gave their colleagues, Zak Boerger, Emily Schneider, and Rory Grennan, a fond farewell on Wednesday as they prepare to leave the Sousa family to follow their careers as archivists, special collections librarians, and outstanding musicians.  In what has become a standing tradition for the Sousa crew, a rousing version of “Happy Birthday” was performed for Emily and Rory in celebration of their recent birthdays, and the singing was  lead by the maestro himself, Mr. Flat Sousa.  Zak, Emily, and Rory will be missed, but never forgotten.  Bon voyage.