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LAYING A TELEPHONE CABLE

Between San Francisco and Oakland

telephone. Within a few weeks, from absolutely distinct sources, two were brought forth. The Bell instrument was superior and in the long lawsuits that followed every court upheld the validity of his patent..

Men who saw the first telephone at the Centennial Exposition at Philadelphia in 1876 may reasonably expect before their allotted seventy years are gone to see a national telephone system with a telephone for every five people (the average family) and by which any subscriber may call up any other subscriber within a radius of a thousand miles. Perhaps, with improved conductors, a man may sit with his telephone and talk to practically any one he wishes anywhere in the United States, perhaps even around the world.

Many of the engineering problems in telegraphy and telephony are much the same. The American Telephone and Telegraph Company now does leased telegraph wire business as well as the two regular telegraph companies. The reason for this is that the wires can be used for telegraphing at the same time that they are being used to telephone; and being copper wires and kept in the repair necessary for telephoning, they are generally credited with being better for telegraphing than

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A TELEPHONE "CENTRAL" OFFICE AT WORK

There are 51 of these offices in New York City and through them any one of the 227,000 subscribers can be connected with any other

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From Stereograph copyright by Underwood & Underwood, N. Y

THE "OVERLAND FREIGHT" ACROSS THE SOUTH AFRICAN VELDT

long, but for the reason that many of the best opportunities for developing tropical Africa are found in the central regions nearly midway between the Atlantic and Indian Oceans. It is a condition preliminary to the opening and prosperity of these regions, on lines of modern enterprise, that they shall have transportation

great Wankie coal field, a little south of Victoria Falls. This coal must go north, as it is now moving south. They must have the better trained black labor of South Africa, which is already filtering north of the Zambesi in an increasing stream along the Cape-to-Cairo Railroad. British publicists are saying this

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PART OF THE CAPE-TO-CAIRO RAILROAD UNDER CONSTRUCTION

year that the rich country of Uganda needs for its full awakening and widest opportunity not only the railroad that binds it with the Indian Ocean but also quick communications with the Anglo-Egyptian Soudan.

This is the hard business basis on which the Cape-to-Cairo project rests. The result is that we hear of trains running to-day to the Broken Hill mines of northern Rhodesia, 1,920 miles from Cape Town (about twice the rail distance from New York to Chicago), crossing the Zambesi River on a steel bridge that was built in five and a half months. The road builders are running a race with the Congo government to see which will first reach the mining district of Katanga, which is pronounced by experts to be one of the largest future sources of copper for the world's supply.

The Katanga line will be a branch of the main road. The route of the trunk line further north is problematical. Our map shows it as now projected to Uganda and down the Nile to the region of great swamps and overflowed lands which divert the route far to the east,

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