It's July 4th weekend and for many (many) years, you would find Bill Brett working at the Esplanade, covering the Boston Pops concert and fireworks. This year marks the first Fourth since the passing of the event's longtime producer David Mugar, who was Bill's dear friend. The organizers will honor David on the Fourth. Photos: Bill Brett and David Mugar and David Mugar with the legendary Pops maestro Arthur Fielder.