"This," said he, "comes nearer to overthrowing the doctrine of the conservation of energy than anything I ever saw." Then came Sir William Thomson, latterly known as Lord Kelvin.

It was fitting that he should be there, for he was the foremost electrical scientist at that time in the world, and had been the engineer of the first Atlantic Cable.

He listened and learned what even he had not known before, that a solid metallic body could take up from the air all the countless varieties of vibrations produced by speech, and that these vibrations could be carried along a wire and reproduced exactly by a second metallic body.

He nodded his head solemnly as he rose from the receiver.

"It DOES speak," he said emphatically.