made him in an instant as rich as one of the grand-dukes of his native in railroading. This invention, which is the nearest approach as yet to known as the "phantom circuit." It enables three messages to run at the It is now a most highly skilled occupation, supporting fully fifteen same time, where only two ran before. A double track of wires is made device startled the telephone men like a flash of lightning out of a land. smaller wires with enamel instead of silk, and by placing coils of a to carry three talk-trains running abreast, a feat made possible by the certain nature at intervals upon the wires. The invention of this last multiple telephony, was conceived by Jacobs in England and Carty in the United States. already saved the telephone companies four million dollars or more, is But the most copper money has been saved--literally tens of millions of This has been done by making better transmitters, by insulating the dollars--by persuading thin wires to work as efficiently as thick ones. reinforce the electric current. It enabled a thin wire to carry as far device, which would seem to be a mere inventor's fantasy if it had not For several years the brains of the telephone men were focussed upon blue sky. It came from outside--from the quiet laboratory of a Columbia professor who had arrived in the United States as a young Hungarian immigrant not many years earlier. From this professor, Michael J. as a thick one, and thus saved as much as forty dollars a wire per mile. As a reward for his cleverness, a shower of gold fell upon Pupin, and this problem--how to reduce the expenditure on copper. One uncanny whimsical disposition of electricity, and which is utterly inconceivable Pupin, came the idea of "loading" a telephone line, in such a way as to