Late one June afternoon Arthur Burton was leaning against a table in the eastern gallery of the main hall at the Philadelphia Exposition. It had been a wonderful day, but it was past dinner time, and he was hot, tired, and hungry. He had seen more wonders that day than he had witnessed in all his life before; but now his uncle and the other judges were in the midst of the Massachusetts educational exhibit, which wasn't half so interesting as the first electric light, or the first grain reaper, or the iceboats. So Arthur had moved away from the new-fashioned school desks and the slate blackboards, and was waiting rather wearily. Suddenly he straightened up. Entering the door near by was the most distinguished visitor at the Centennial, the tall, handsome Dom Pedro, Emperor of Brazil, with the Empress and a bevy of courtiers. To Arthur's amazement, His Majesty walked directly up to the table against which he himself was standing; and looking beyond the little boy, he said with outstretched hand and a pleasant smile: "How do you do, Mr. Bell? I am very glad to see you and your work." Till then Arthur had scarcely noticed a sallow, dark-haired young man who had been sitting behind the little table, nor had he paid the slightest attention to some pieces of wood and iron with wire attached lying on the table. But now, the young man and his material had become decidedly interesting. [Illustration: DOM PEDRO II] "I remember very pleasantly," continued Dom Pedro, "my visit to your class in Boston University when you were teaching deaf mutes to speak by means of visible speech. You were working out a new method, I remember. I suppose this is apparatus that you have devised in that connection." "I thank Your Majesty," stammered the surprised young man, who for a moment had been at a loss to recall who his royal visitor might be. "I shall be delighted to explain my apparatus. But it has nothing to do with teaching deaf mutes to speak. It is more wonderful than that. It speaks itself; that is, it reproduces sounds. It is the improvement on the telegraph that the world has awaited for years. "You see, I found in my experiments that I could transmit spoken words by electric current through a telegraph wire so that those words could be reproduced by vibrations at the other end of the wire. I suppose my invention might be called a speaking telegraph." By this time all the judges had joined the Emperor's party. Arthur fell back to his uncle's side, but he could still hear and see everything. "Now, Your Majesty," continued Mr. Bell, "if you will press your ear against the lid of this iron box, I think in a moment you will have a surprise." At these words, Mr. Bell's assistant, who had come up to the group during the conversation, went to another table several rods away and quite out of hearing. The Emperor bent down expectantly. The judges looked rather incredulous, but they were all interested.