Page:Tom Swift and His Photo Telephone.djvu/11

Rh anyhow? Merely another form of motion; isn't it?"

"Well, yes, Tom, I suppose it is."

"Of course it is," said Tom. "With vibrations of a certain length and rapidity we get sound—the faster the vibration per second the higher the sound note. Now, then, we have sound waves, or vibrations, traveling at the rate of a mile in a little less than five seconds; that is, with the air at a temperature of sixty degrees. With each increase of a degree of temperature we get an increase of about a foot per second in the rapidity with which sound travels.

"Now, then, light shoots along at the rate of 186,000,000 miles a second. That is more than many times around the earth in a second of time. So we have sound, one kind of wave motion, or energy; we have light, a higher degree of vibration or wave motion, and then we come to electricity—and nobody has ever yet exactly measured the intensity or speed of the electric vibrations.

"But what I'm getting at is this—that electricity must travel pretty nearly as fast as light—if not faster. So I believe that electricity and light have about the same kind of vibrations, or wave motion.

"Now, then, if they do have—and I admit