This advertisement is from 1914. The text of the ad is reprinted below:

Unseen forces behind your telephone

The telephone instrument is a common sight, but it affords no idea of the magnitude of the mechanical equipment by which it is made effective.

To give you some conception of the great number of persons and the enormous quantity of materials required to maintain an always-efficient service, various comparisons are here presented.

The cost of these materials unassembled is only 45% of the cost of constructing the telephone plant.

Poles
enough to build a stockade around California—12,480,000 of them, worth in the lumber yard about $40,000,000.

Wire
to coil around the earth 621 times—15,460,000 miles of it, worth about $100,000,000, including 260 tons of copper, worth $88,000,000.

Lead and Tin
to load 6,600 coal cars—being 659,960,000 pounds, worth more than $37,000,000.

Conduits
to go five times through the earth from pole to pole—225,778m000 feet, worth in the warehouse $9,000,000.

Telephones
enough to string around Lake Erie—8,000,000 of them, 5,000,000 Bell-owned, which, with equipment, cost at the factory $45,000,000.

Switchboards
in a line would extend thirty-six miles—55,000 of them, which cost, unassembled, 90,000,000.

Buildings
sufficient to house a city of 150,000—more than a thousand buildings, which, unfurnished, and without land, cost $44,000,000.

People
equal in numbers to the entire population of Wyoming—150,000 Bell System employees, not including those of connecting companies.

The poles are set all over this country, and strung with wires and cables; the conduits are buried under the great cities; the telephones are installed in separate homes and offices; the switchboards housed., connected and supplemented with other machinery, and the whole Bell System kept in running order so that each subscriber may talk at any time, anywhere.

American Telephone and Telegraph Company and Associated Companies

One Policy      One System      Universal Service

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