For the purpose of one brief lecture, it is necessary to set close boundaries. In expansive mood one might, with your permission, discuss the aim in general of aeronautical research, the bending of this Force of Nature to the Use and Convenience of Man; a subject so wide and so difficult, especially our critics would say in respect of Convenience, as to call for a series of lectures rather than this single one. The immediate aims can be dealt with more briefly, and it is that which T propose to attempt. They are, in the first place, safety im flight, and, in the second, increase in what is termed performance. No other aim 6f aeronautical research compares in importance with these.