Unpublished letter and drawings, on Henry Smeathman's designs for a flying vessel by [George] Cumberland Covering letter from Cumberland to Joseph Banks introduces the five accompanying pencil drawings, showing dirigible balloons based off of a design by Henry Smeathman, who had witnessed the Montgolfier balloon demonstrations in 1783. Subject: Engineering Written at Church Court, Clements Lane, Lombard Street [London]. 4 March 1784