I have been deeply appreciative of the action of the Council in inviting me to deliver this lecture. No one could be otherwise. The Wilbur Wright. Lectureship has been illustrious in the qualifications of the thirty speakers who have been my predecessors on this platform ; but it is illustrious also in itself, in the manner of its founding, and in the manner in which the Royal Aeronautical Society has carried it on in an unbroken series through two wars and the years between.