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AFTER A SNOWSTORM
vigor to the sound of the voice after it Another engineering invention that has has passed through a vacuum.
materially aided in making practically A handmaiden to the repeater is the possible the coast to coast talk is the "phantom circuit", which may be de- open finder of Bauer. It is one thing for scribed as a species of wireless. In the the talk to be theoretically possible and modern telephone plant all circuits are another to make the talk practical for metallic, that is, there are two wires for public use at any time of the day or night. each circuit, the ground return not being During the last months of the year 1914 used as in telegraphy. Some years ago, the engineers working in New York and
FINDING THE WAY ACROSS A RIVER The miles of wire that you see strung along the railways and the city streets do not comprise the total. There are
rivers like the Hudson, the Mississippi, the Missouri, to be crossed in submarine cables.
Carty in the United States and Jacobs San Francisco talked to each other frein England discovered that three mes- quently, but in a jargon of telephonese sages could be run on two trunk wires at that no untrained ear could understand. the same time, instead of two messages, Then, suppose the line had been earlier if the trunks were crossed at intervals opened to the public, and had to be shut and perfectly balanced electrically. Three again because of the need of makyears ago the engineers discovered how ing repairs? The public would have beto load No. 8 (long-distance) wires by come disgruntled and declared the line the Pupin method and at the same time non-existent. "to phantom" them, and by this discov- Just a year ago, Bauer, who works in ery were enabled to make the two wires the myriad-wired testing distance departbetween Chicago and New York carry ment of New York, discovered a new three messages. The phantom circuit way of detecting and locating exactly has already saved five or six million dol- any unbalanced wire, that is, a wire that lars. It made the New York to Denver refuses to continue the talk-sound at line an economic possibility.
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