The final thought is that it is all a matter of buildup. An officer can cut his audience to his own size, and strengthen his powers and his confidence as he goes along. That is his supreme advantage. He can start with a short talk to a minor working detail and move from that to a more formal address before a slightly larger group. By taking it gradually, and increasing his store of knowledge in the interim period, he will see the time come when he can hold any audience in the hollow of his hand. This is precisely the routine which was followed by most of the military leaders who have been celebrated for their command of speech. CHAPTER TWENTY-ONE THE ART OF INSTRUCTION _Keep it simple._ _Have but one main object._ _Stay on the course._ _Remain cheerful._ _Be enthusiastic._ _Put it out as if the ideas were as interesting and novel to you, as to your audience._ By abiding by these few simple rules you will keep cool, preserve continuity and hold your audience. Instruction is just about the begin-all and end-all of every military officer's job. He spends the greater part of his professional life either pitching it or catching it, and the game doesn't stop until he is at last retired. Should he become a Supreme Commander, even, this is one thing that does not change; it remains a give-and-take proposition. Part of his time is taken instructing his staff as to what he wants done and just as much of it is spent in being instructed by his staff as to the means available for the doing of it. Instruction is the generator of unified action. It is the transmission belt by which the lessons of experience are passed to untrained men. Left uninstructed, men may progress only by trial-and-error and the hard bumps which come of not knowing the way. Need more than that be said to suggest that the officer who builds a competent skill in this field, so that it becomes a part of his reputation, has at the same time built the most solid kind of a foundation under his service career? The services do not discard that kind of man when the economy pinch comes and the establishment has to contract. The Reservist, who is known as a good instructor, is always on the preferred list. In any period of emergency, such officers move rapidly to the top; there are always more good jobs than there are good men. Look back over the lineup of distinguished commanders from World War II! It will be found that the high percentage of them first attracted notice by _being good school men_.