“It seems a pity to fool a door that is so polite,” Harry said. “Look,” he added; “there is a nice little girl trying it. See her laugh! It reminds her of ‘Alice in Wonderland.’”
MINES AND MINING BUILDING.
Germany had a historical exhibit showing the earlier and cruder forms of dynamos; but the boys were not very well acquainted with dynamos. Mr. Douglass tried to explain how they worked; but after he found he had lost the trail of his ideas, he said frankly: “Well, I thought I knew the theory of dynamos and converters; but when I see the real machines here, they seem so much more complicated than the ones in the text-books that I find I don’t know the reason for many of the parts.”
AN EXHIBIT OF RAILS: MINING BUILDING.
The boys took more interest in the Western Union exhibit, where they saw Professor Morse’s earliest receiving instrument, and photographs of the original first message, “What hath God wrought!” The same words were affixed to the front of the pavilion, where not only the original instrument but the modern quadruplex system—a method of sending two messages each way, and all at once, on a single wire—was shown.
“I wish,” said Harry, “that I could see the game of leap-frog these quadruped signals must play to get by on the same track!”
Farther on were other German or Austrian exhibits, in one of which the boys saw a dome copied from that on some central telegraph station, and made up entirely of openwork so as to give room for hundreds of insulators. These insulators made up the curved surface of the dome, and the effect was very decorative, while the arrangement must have been a great saving of space.
What a lot of things there were besides! There was an electric cooking-apparatus where water was boiled upon a flat iron plate; there were clocks so contrived as to note the times a watchman touched a button on the front; there was Professor Gray’s telautograph, which merits some description.