I am making my second Presidential Address the opportunity to do little more than muse aloud on a theme which is fashionable rather than original. It will be entirely personal and in no way representative of Admiralty views. I can describe the theme as the way in which man is getting along, in our particular field of navigation, with his inventions of mechanical devices, or as Shakespeare collectively and descriptively calls them—his ‘engines’. I could alternatively and not unreasonably describe it as the way in which man is becoming increasingly dependent on his mechanical aids. Yet, that would convey an impression of his going into an unduly early decline or of his doing something wrong. Obviously, he gains in being able to achieve things which he could not do unaided, but obviously, also, he must avoid rendering himself helpless if there is a chance of his inventions failing him at a critical moment.