The longer I live, the more deeply am I convinced that that which makes the difference between one man and another—between the weak and powerful, the great and insignificant, is energy—invincible determination—a purpose once formed, and then death or victory.—FOWELL BUXTON. In the measure in which thou seekest to do thy duty shalt thou know what is in thee. But what is thy duty? The demand of the hour.—GOETHE. A strong, defiant purpose is many-handed, and lays hold of whatever is near that can serve it; it has a magnetic power that draws to itself whatever is kindred.—T. T. MUNGER. I Hard Work: the Secret of a Great Inventor’s Genius. TO discover the opinion of Thomas A. Edison concerning what makes and constitutes success in life is an easy matter, if one can only discover Mr. Edison. I camped three weeks in the vicinity of Orange, N. J., awaiting the opportunity to come upon the great inventor and voice my questions. It seemed a rather hopeless and discouraging affair until he was really before me; but, truth to say, he is one of the most accessible of men, and only reluctantly allows himself to be hedged in by the pressure of endless affairs. “Mr. Edison is always glad to see any visitor,” said a gentleman who is constantly with him, “except when he is hot on the trail of something he has been working for, and then it is as much as a man’s head is worth to come in on him.” He certainly was not hot on the trail of anything on the morning when, for seemingly the tenth time, I rang at the gate in the fence which surrounds the laboratory on Valley Road, Orange. A young man appeared, who conducted me up the walk to the elegant office and library of the great laboratory. It is a place, this library, not to be passed through without thought, for with a further store of volumes in his home, it contains one of the most costly and well-equipped scientific libraries in the world; the collection of writings on patent laws and patents, for instance, is absolutely exhaustive. It gives, at a glance, an idea of the breadth of the thought and sympathy of this man who grew up with scarcely a common school education. On the second floor, in one of the offices of the machine-shop, I was asked to wait, while a grimy youth disappeared with my card, which he said he would “slip under the door of Mr. Edison’s office.” “Curious,” I thought; “what a lord this man must be if they dare not even knock at his door!” Thinking of this and gazing out of the window, I waited until a working man, who had entered softly, came up beside me. He looked with a sort of “Well, what is it?” in his eyes, and quickly it began to come to me that the man in the sooty, oil-stained clothes was Edison himself. The working garb seemed rather incongruous, but there was no mistaking the broad forehead, with its shock of blackish hair streaked with gray. The gray eyes, too, were revelations in the way of alert comprehensiveness. “Oh!” was all I could get out at the time.