Scope and Contents Collection contains historical correspondence and documents related to early aviators, scientists, organizations, military of the 18th, 19th and 20th centuries. RHC1 - James Sadler Letter to Lord Mulgrave, September 3, 1808, Box 2 James Sadler (1751-1828) was the first Englishman to rise in a hot air balloon. Collection contains a letter from Sadler to Lord Mulgrave requesting an interview to discuss an idea that would help defeat...