The history of telephone service covers little more than the normal span
of a man's lifetime. Yet it has become almost universally accepted in the
United States as a way to get things done effectively and conveniently. In
fact, most people would find getting along without it next to impossible.
The long distance side of the service has had a steady expansion.
over hundreds of miles is now an ordinary affair, and the volume of calls
with overseas points keeps on climbing. The telephone has bridged vast
distances and brought people around the world closer together.
In the first section of this book, we explore the role of Long Lines in
the Bell System, the early days of telephony, long distance services and
facilities of today, and the working arrangements Long Lines has with its
partners in the long distance telephone business.
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Long Lines And Other Bell
A homesick college girl in Massachusetts is cheered up
by a telephone chat with her parents in Oregon .... A quick call to Italy
helps an Ohio manufacturer close an important deal ....
Here are two different needs, yet there is a common denominator. Both
needs are filled with the help of Long Lines, the long distance operating
department of American Telephone and Telegraph Company, which provides
interstate and international communications services. And both illustrate
the essential purpose of Long Lines: to enable people--separated by
hundreds or thousands of miles-to communicate quickly with one another.
To do so, Long Lines operates a network of facilities for nationwide and
worldwide communications. Its circuits interconnect the territories of the
telephone companies that provide local service throughout the country.
With its communications counterparts abroad, Long Lines furnishes circuits
linking the United States with countries around the globe.
Long Lines and its partners in this communications enterprise are part of
a group called the Bell System. The role of each member in this group is
described briefly below.
• AT&T is the parent company. It maintains a central
staff in New York to advise and assist its Long Lines Department and
companies on their common problems.
• Western Electric is the manufacturing and supply unit. It guarantees
the high quality and compatibility of the billions of components that
make up the Bell System's network.
• Bell Telephone Laboratories helps assure the future of the business by
conducting a continuous search ]or new and more effective ways for
people to communicate.
• Twenty-three telephone companies, known as Associated Companies,
furnish communications in their own territories. Each meets the special
needs of the areas it serves.
• Long Lines interconnects the territories of these companies (and some
2,000 others which are not part of the Bell System) to give nationwide
and worldwide service.
The key to the Bell System's effectiveness is the
careful fitting together of its many parts: the combination of research at
Bell Laboratories, manufacturing at Western Electric, and operations at
Long Lines and the associated companies to achieve a balanced allocation
of resources in providing Bell System customers with the best
communications service in the world.
Obligations to the Public
Long Lines and the other operating units of the Bell System have a
definite obligation to the public. Their responsibility--and sole reason
for existence -- is to serve and serve well.
The Bell System has acquired an excellent reputation for service over the
years. It is a progressive business. It makes important contributions to
society and to the general economy. Competent and forward-looking people
work in it.
To meet its responsibilities, the Bell System follows a fundamental
the best communications service to the public at the
lowest cost consistent with financial safety;
steady work at fair wages to employees;
a reasonable return to those who have invested in the
That policy has been expressed publicly on a number of
occasions since the business began. While the business has changed and
expanded over the years, its basic operating principles have remained the
In a recent AT&T annual report, the policy was put in a contemporary
"Our job as we see it is to provide the best possible communications
service and make it continuously better and more abundant.
"This means service that our customers will find more and more satisfying
to use, more dependable, more versatile, more economical, more valuable.
"To accomplish this we must all the time seek to develop new knowledge and
resources that will meet changing social, industrial and national needs.
"We must strive to hold down costs so that charges to customers will be as
low as possible consistent with the kinds of service they desire.
"We must maintain complete financial integrity and earn profits that will
justify the continuing confidence of all who invest in our enterprise.
"We must bring into the business people who have the will and can learn
the skills for quality performance, and offer them opportunity regardless
of color or creed. Good wages, first-rate training, challenge on the job,
and for each employee the chance to get ahead according to ability-these
It's a Regulated Business
Like other public utilities, Long Lines and the
associated companies are subject to governmental regulation in a variety
of matters, including the quality and the kind of services, and the
charges for them. This is because we don't have the same kind of
competition as other, non-regulated businesses -- though we do compete
for, among other things, competent, skilled employees, capital from
investors and a fair share of the public's dollar.
Nearly every state has a public service commission which regulates
communications within its borders. Since Long Lines operates between
states-- and between continents--it comes under the jurisdiction of the
Federal Communications Commission. The commission was created by an act of
Congress, known as the Communications Act of 1934, "for the purpose of
regulating interstate and foreign commerce in communication by wire and
The Commission's Job
Under the Act, the FCC must see to it that any U. S. communications
carrier giving interstate or international service meets all reasonable
requests for service and furnishes service without discrimination, at
rates which are just and reasonable. The carrier must publish rates and
regulations for its services and file them with the commission. It also
must obtain approval from the commission for construction of new
The FCC evaluates the carrier's property and prescribes the accounting
methods the carrier is to use. The commission also regulates the amount of
depreciation dollars which may be charged against operating expenses so
the carrier can recover the capital invested in plant during its service
The Bell System has lived with regulation for more than half a century. It
recognizes the necessity for it. At the same time, the Bell System
believes that the interests of its customers are best served when it is
allowed the freedom and incentive to enhance both service and profits
through self-initiated operating efficiencies and technological
There is overwhelming evidence that the U.S. system of entrusting
communications service to private enterprise under public regulation has
been effective. The chief testimony to its success is the general
agreement around the world that the U.S. has outstanding communications
service. Much of the credit belongs, of course, to telephone people. But
the enlightened attitude of most regulatory authorities over the years has
helped a great deal to make good service possible.
The Early Days
For our purposes, the telephone industry began on March 7, 1876. That's
when the U.S. Patent Office issued Patent No. 174,465 to Alexander Graham
Actually, the patent was issued to him for what was described as an
improvement in telegraphy. But in this particular case, telegraphy dropped
out of the picture three days later.
That day, March 10, 1876, Bell was working behind closed doors in a room
in Boston. His assistant, Thomas Watson, was out of earshot in another
room down the hall. Linking the two rooms was the primitive telephone
device that Bell and Watson were working on. Bell, accidentally spilling
battery acid on his clothes, cried out, "Mr. Watson, come here, I want
you!" In a moment Watson came rushing in, shouting, "Mr. Bell, I heard
every word you said, distinctly."
That was the first sentence heard over the telephone.
It showed that the so-called improvement in telegraphy was actually far
removed from telegraphy.
Bell had been working for some time on harnessing sound, just as
latter-day researchers spent years studying techniques to harness the
atom. He concentrated on the anatomy of sound waves which, as he knew,
consist of vibrations. Sound waves reaching the ear cause the eardrums to
vibrate, and the vibrations, translated into subtle, electrochemical
pulses in nerve endings and the brain, tell the listener what he is
hearing. Each sound has its own peculiar frequency--the number of times it
vibrates each second.
Sound waves do not travel very far or fast. And the farther they travel
the fainter they become. But when their electrical counterparts travel
over telephone circuits, their speed may be increased as much as 900,000
times. Though these electrical vibrations lose intensity with distance
from their source, they can be amplified at intervals and "reconstructed"
with practically the same clarity and tone as the original spoken message.
The fact that Bell was an elocution professor and an expert in instructing
the deaf gave him a decided "edge" over other experimenters. He had a
great deal of knowledge both about vocal chord vibrations and the workings
of the human ear. The discovery that led to his invention of the telephone
was that waves of electricity could be created with the same pattern as
the waves of air a person sets in motion when he speaks.
The Birth of the Bell System
Once it was established that Bell's invention worked, the next move was to
put it to practical use. The first telephone company was set up in July,
1877 in Boston as the Bell Telephone Company, Gardiner Greene Hubbard,
Hubbard, whose daughter was soon to marry Bell, was an attorney. His
legacy to the Bell System was the leasing and licensing arrangements that
led directly to the sale of service only. He got the idea from a
Massachusetts shoe machinery outfit that leased its sewing machines to
shoemakers, retained title to the machines and received a royalty for
every pair of shoes its machines sewed.
Hubbard made his decision despite strong pressure from most of his
colleagues and in spite of a sore need for money at a time when the sale
of telephones would undoubtedly have brought in more income. He held
firmly to the leasing principle as the wisest and best for the telephone
business. History proved him right. The leasing of telephones has been a
vital factor in the development of today's unified network.
After various corporate changes, the National Bell Telephone Company was
formed in Boston early in 1879. A year later, because of expanding
business, Bell interests again reorganized to form the American Bell
Telephone Company, established by an act of the Massachusetts Legislature.
At that time, there were nearly 48,000 telephones in the U.S. and some 400
exchanges. Experiments with long distance telephoning had been going on
almost since the telephone was invented. However, interconnection among
the exchanges was complex and costly.
To meet that situation, AT&T was formed in 1885 as a subsidiary of
American Bell. Its purpose was to build lines to connect the scattered
telephone exchanges in the U.S. and, as the certificate of incorporation
put it, "also by cable and other appropriate means with the rest of the
This was a forward-looking document when you consider that at the time
there were fewer than 150,000 telephones in the whole country.
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The first job of the newly organized American Telephone and Telegraph
Company was to construct an open wire pole line between New York and
The line was completed and work began on other projects. From
Philadelphia, it was extended south to Washington, D.C., and an
experimental line, constructed earlier between New York and Boston, was
rebuilt. And work also was started on a line from New York to Albany and
on to Buffalo.
Construction steadily pushed westward. The first telephone lines reached
Chicago from the East in 1892; St. Louis in 1896; Minneapolis and Omaha in
1897; and Kansas City in 1898. Those lines were connected to intermediate
cities along the way and branches extended from important switching points
to adjacent cities.
By 1906, there were telephone lines from the East Coast as far west as
Texas, Oklahoma, Nebraska and Minnesota. The primitive telephone network,
making the most of the capabilities of existing equipment and facilities,
had stretched out as far as it could.
From a long distance standpoint, the period up to 1906 chiefly involved
the extension and construction of telephone plant, together with the
growth and development of the organization. The plant used in providing
telephone service was placed on a sound engineering footing. Research,
development and testing were continuing in many fields. The virtues of
hard-drawn copper for line wire and the new development of using two wires
to form a talking circuit (instead of the one "grounded" wire that
telephone men started out with) were demonstrated. Engineers also were
able to eliminate objectionable "cross-talk" by interchanging the
positions of the wires at certain poles along the line.
But there were still difficulties to overcome. For one thing, a way had to
be found to lengthen the distance over which speech could be transmitted.
A step in this direction was the use of "loading coils" on long distance
circuits. When installed at the right intervals, the coils helped
compensate for energy losses along the route; they had the effect of
making electrical impulses travel a greater distance with relatively
unimpaired transmission. Using loading coils, telephone engineers extended
long distance service westward from the Atlantic seaboard to Denver by
1911 and to Salt Lake City by 1913.
Another problem, also involving energy losses, stemmed from the expansion
of the telephone network itself. Open wire line facilities were becoming
congested in the more heavily populated sections of the country, and local
ordinances in many towns and cities called for elimination of pole lines
from main streets. This meant placing cables underground. However, putting
lines in cables-even for a few miles through a congested district--caused
additional energy losses that materially shortened the length of
By 1910 a solution was in sight. Design and manufacturing technique had
reached the point where a cable suitable for carrying long distance
circuits could be built.
Construction of the first long distance cable was begun. Completely
underground, it extended from Boston to Washington via New York, with some
of its conductors terminating at cities along the route. The first
"through" circuit along the entire length of the new cable went into
service in 1914.
At the same time, much experimental work was directed toward the
development of amplifiers more effective than loading coils. Several new
methods were devised, but it was not until the invention of the
three-element vacuum tube--plus a suitable electrical circuit--that the
best amplifier became available. These amplifiers, known as "telephone
repeaters," made it possible to extend the range of man's voice clear
across the country. The first transcontinental telephone line, consisting
of three circuits, opened for service in 1915.
With the advent of the telephone repeater, construction of long distance
cable lines got into full swing. The relatively large energy losses of the
small conductors in cables could now be counteracted by placing repeaters
at frequent intervals along the line.
The capacity of cable, already greater than the capacity of open wire, was
given a boost through the development of "carrier" transmission
techniques. This made it possible to transmit additional conversations
over pairs of wires.
Cable carried many more circuits than open wire, and was much less
vulnerable to storm damage. In the next twenty years or so, cable replaced
most of the open wire in the East and Midwest, where traffic loads were
greatest and storm hazards most severe.
As more efficient systems were being developed for service over land, Bell
engineers were looking into the possibilities of radio for telephoning
overseas. In 1915--a few months after the first transcontinental line went
into service--the first words were transmitted by radiotelephone across
the Atlantic. H. R. Shreeve, a Bell engineer taking part in an experiment,
was stationed at the Eiffel Tower in Paris. He heard the words "... and
now, Shreeve, good night" addressed to him by a colleague through a
transmitting station at Arlington, Va.
But it took a dozen years before satisfactory equipment and methods could
be developed for commercial service. In 1927, overseas service was opened
between New York and London as a cooperative enterprise of AT&T and the
British Post Office.
Man's voice, having spanned the continent, had now reached out across the
ocean. This was the start of telephone service which Long Lines now
provides on a worldwide scale.
Many Kinds of Services
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Today, Long Lines offers a wide variety of
communications services--including long distance and overseas calling and
data transmission--that play a significant role in the lives of Americans.
The most widely used and best known is regular long distance telephone
service. It is provided over the nationwide network by Long Lines and its
telephone company partners across the nation. An important feature of the
service is direct distance dialing (DDD), which enables customers to dial
their own calls. Briefly, DDD works this way:
For telephone purposes the U.S. and Canada (and a number of Caribbean
points) are divided into areas, each with its own code. A customer who
calls a telephone in a different area dials the area code first. That
tells the equipment the section of the country the call is headed for. As
the rest of the number is dialed, the equipment picks the right city. If
direct routes are busy, this same equipment tries alternate paths until it
finds an idle circuit to establish the connection. Meanwhile, other
equipment keeps track of how long the call lasted and makes a record of
information needed for billing purposes.
Another service is the transmission of network television and radio
programs to stations throughout the country. Long Lines technicians see to
it that these programs reach the right stations at just the right moment.
That means making the proper switches with split-second timing.
Long distance circuits also help in the dissemination of news. Speed is
essential, so a good deal of the national news in daily newspapers is
flashed over teletypewriter links provided by Long Lines.
News pictures, too, travel over tong distance circuits. A picture of an
event in Chicago, for instance, is placed on a telephotograph machine
there. The signals are transmitted over Long Lines facilities and, a few
minutes later, an exact copy is reproduced on telephotograph machines in
the offices of newspapers throughout the country.
Besides helping to bring people entertainment and keep them abreast of the
news, Long Lines provides many kinds of services to meet the nation's
communications needs. Here are a few samples:
For business firms that make a large number of long
distance calls a day, there is Wide Area Telephone Service. This enables
them to telephone all they want at a flat monthly rate, instead of
having each call charged separately. This service is available across
the U.S. continent or by region, and the customer can have it full-time
or on a measured-time basis.
Data transmission is provided at various speeds. With
Data-Phone® service, for example, a customer can dial a data
processing unit in a distant city and transmit machine talk over regular
telephone lines at about 3,000 words a minute. For greater speeds there
are circuits or groups of circuits specially arranged to produce large
data channels. Some of these are capable of transmitting hundreds of
thousands of words a minute. This service allows the rapid accumulation,
storage and arrangement of data--in a variety of forms--for the
efficient operation of business, administrative and technological
organizations. Another service provides lines to interconnect widely
Many businesses use private line telephone and
teletypewriter services to link branch offices with their headquarters.
One form is the "switched network." The interconnecting lines are
reserved for the exclusive use of each customer, but calls are switched
through equipment all telephone customers use in common. Since the
switching systems are on telephone company premises, maintenance is
considerably easier, and customers are spared the expense of providing
floor space for telephone equipment.
These and other services have come about through a
succession of technological advances in the art of communications.
Facilities for Service
Technological development is fundamental to progress in
the Bell System.
Advances in the art of communication continuously refresh the business.
They help create new services and improve existing services. They make
service in general more dependable, more flexible, and more valuable to
That has certainly been demonstrated in long distance telephoning. Vacuum
tubes extended the range of the spoken word across the continent,
Carrier systems increased the capacity of long distance
facilities, and radiotelephone, submarine cable and satellites brought the
world within "reach" of the average telephone user.
Today, there are two main types of facilities in use for long distance
communications; coaxial cable and microwave radio relay. A newcomer in the
field, the communications satellite, has great promise. All three are
broadband transmission systems. Such systems--using either cable
conductors or radio channels--transmit over a band of electrical
frequencies several million cycles wide. With terminal equipment at each
end, this wide band is subdivided into smaller bands for transmitting
telephone, television, data or other kinds of signals.
Another basic facility--for overseas service--is submarine cable, a
special form of coaxial cable; it made transmission for overseas calling
as clear as telephoning across town.
Coax: The Growth of Super Cables
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Coaxial cable was the first wideband long distance
transmission system. It made its commercial debut between Minneapolis and
Stevens Point, Wis., in 1941. Using a carrier system known as L1, it
provided 480 two-way telephone circuits in a pair of tubes. It had two
pairs of tubes-one pair for regular service and the other for standby
The coaxial conductor is a copper tube with a wire held in its center by
small plastic insulators spaced about an inch apart. The name "coaxial"
stems from the fact that both the tube and wire have the same center or
axis. Transmission is one way over a tube, so telephone conversations
require the use of two coaxials.
The rising demand for communications service after World War II spurred
efforts to increase the capacity of coaxial cable. The problem was solved
by putting more coaxia]s in each cable and devising ways to transmit a
wider band of frequencies through the individual coaxials.
The first of the really high-capacity cables went into service from coast
to coast in 1964. With 12 coaxial tubes and a more advanced carrier system
called L3, it has a capacity of 9,300 telephone circuits. Next came a
cable which has 20 tubes, uses an L4 carrier system and is capable of
handling 32,400 simultaneous telephone conversations. The first major
20-tube coaxial cables run along the eastern seaboard and westward from
New England to Chicago.
The super-capacity coaxial links of the 1960s are buried deeper than
previous cables. The main stations, amplifiers and power feed stations are
all placed underground, and the routes skirt major cities and avoid
possible target areas. They are designed to withstand natural disasters as
well as such possible crises as nuclear attacks.
Microwave: An Electronic Pony Express
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The development of microwave radio has followed a
similar pattern of steady increase in capacity.
The first system of this kind went into service between Boston and New
York in 1947. It provided two broadband radio channels in each direction,
each capable of handling one television signal or 480 telephone circuits.
Since then, the capacity has been increased significantly a number of
times: to 4,800 circuits in a system called TD 2; to 9,000 in TD 2A; and
to 12,000 circuits in TD 2B and a new solid-state system called TD 3.
Microwaves are about one to three inches long. Like light waves, they
travel in straight lines and, in general, do not follow the curvature of
the earth. They can be focused sharply and aimed from point to point. Less
than one watt of power (about the same needed for a pocket flashlight) is
enough to speed them on their way over the 30 miles separating stations on
a radio relay route.
Transmission by microwaves is rarely affected by atmospheric
interference-static and lightning, for example. Microwave paths do not
require rights-of-way or poles. Since they are airborne, they are not
subject to the hazards of being plowed up or accidentally damaged.
Maintenance costs are involved only at terminal and intermediate repeater
On the Ocean Floor
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The introduction of ocean cable in the 1950s increased
the quality and reliability of overseas telephone service.
The first deep-sea telephone cable system across the Atlantic used two
cables--one for each direction of speech--and initially had a capacity of
36 telephone conversations. The capacity was later boosted, first by
special terminal equipment and then by a system called TASI.
TASI -- short for Time Assignment Speech Interpolation--takes advantage of
pauses in conversations when one party is listening, or stops speaking to
catch his breath or gather his thoughts. With electronic switching at
lightning speed, the equipment puts a momentarily idle voice-path at the
disposal of someone who is starting to speak.
Bell Laboratories later developed an underseas cable system with an
initial capacity of 138 telephone circuits. This system, which uses a
single cable that transmits in both directions, can also be used with TASI
to increase its conversation-carrying capability. Systems of this type
have been placed in the Atlantic, Pacific and Caribbean.
The demand for service continued to grow. Bell Laboratories developed an
ocean cable system able to handle even larger volumes of calls. That one,
equipped with transistorized repeaters, has a minimum capacity of 720
telephone circuits. The first cable of that type went to work in the
Caribbean in 1968.
To lay the thousands of miles of cable required to expand overseas
service, AT&T built a cable ship--the C.S. Long Lines--for its own use.
The vessel is equipped to handle the latest types of submarine telephone
cables. Three tanks in the ship can hold many miles of deep-sea cable, and
there are auxiliary tanks for storing cable for repairs, in the laying
process, both cable and repeaters pass through special electrohydraulic
machinery which makes it possible to lay the repeaters without slowing
Links Through Outer Space
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A broadband system suitable for both overseas and
domestic telephoning is the communications satellite first developed in
the early 1960s. Satellites allow the extension of microwave transmission
techniques to outer space. Someday a single satellite system may furnish
tens of thousands of circuits for domestic service alone. Satellites in
conjunction with terrestrial circuits also provide greater diversification
of facilities to assure service continuity.
Satellite facilities in use today for overseas services are supplied by
the Communications Satellite Corporation (Comsat). This is a private
enterprise set up by Act of Congress in 1962; Comsat also is a member of
Intelsat, an international group working on development of worldwide
satellite communications. AT&T is Comsat's largest share owner and its
largest customer for satellite circuits. AT&T and other international
common carriers share ownership with Comsat in the U. S. earth stations
that interconnect satellite circuits with domestic networks.
The Bell System was a pioneer in the satellite communications field. It
built the world's first earth station at Andover, Maine, in 1961, and the
first active communications satellites--Telstar ® I and II--to test the
feasibility of overseas communications by satellite.
Two development programs were chiefly responsible for American successes
in satellite communications: the government's space and missile efforts,
and private industry's research in communications. Clearly, communication
satellites would not be possible without the propulsion and guidance
systems to put them in orbit. But it is equally clear that these
satellites would be voiceless without the advances in microwave and
solid-state technology accomplished by industry-sponsored research.
The Bell System's major contributions to space communications included
development of the transistor, the solar battery and .the low-noise maser
amplifier. Without these basic components, communicating by satellite
would be impossible.
With the Partners
Rapid changes in communications needs--and in the technology to fill these
needs--pose challenges of national and international proportions.
To meet these challenges, Long Lines works closely with the telephone
operating companies. With them, Long Lines plans, operates and manages an
increasingly complex network. The common goal, of course, is to provide
the best possible service.
An important contribution to smooth teamwork is the license contracts
between AT&T and its subsidiaries. These contracts describe the sort of
assistance AT&T gives its subsidiaries, and they outline the
responsibilities of Long Lines and the 23 operating Bell System companies.
Under these contracts, the overall responsibility of Long Lines is to
build, operate and maintain the interconnecting facilities that tie
together regional telephone systems to form a unified communications
Like the operating companies, Long Lines receives important services from
AT&T's headquarters staff-including research, financing and engineering.
In return for these services, Long Lines pays its share of the costs of
Long Lines and the operating companies have reciprocal arrangements
designed for economical and efficient operation of the network.
For example, handling of message traffic--belonging either to Long Lines
or to an operating company--may be turned over to the partner in the best
position to do a particular job more economically or effectively. There
also are agreements under which either partner may use plant facilities
owned by the other.
In plant maintenance, certain agreements stipulate that the forces of
either Long Lines or an operating company may perform maintenance or
service work for both at specific points. Under another arrangement, one
of the partners can take care of all the work involved in construction or
additions to jointly used plant and bill the other for its portion.
And there are agreements on the division of revenues. These set forth
procedures whereby Long Lines and the operating companies are paid for
expenses incurred--and facilities used--in furnishing interstate
Dividing the Revenues
Each Bell System partner involved in providing interstate service -- Long
Lines and the 23 operating companies--furnishes plant and performs
operations to make the service possible; the purpose of the division of
revenues agreement is to make sure that each is paid according to its
The actual process of dividing revenues is somewhat complex. But the
principles behind it are quite simple. Briefly, the arrangement works this
Step one: Every month, each partner determines
the amount it paid to connecting (or independent) telephone companies
for their part in helping to provide the service; the amount of plant it
furnished; the applicable reserves; and the expenses it incurred in
connection with interstate service.
Step two: The revenues each partner collects from its customers
are added together into a single total.
Step three: Out of this total, each partner is reimbursed for its
expenses and the payments it makes to connecting telephone companies.
Step four: The remaining money--that is, the amount available for
return on plant investment (profit)-is divided among the partners in
proportion to the amount of net plant each provides for the service.
This method of handling revenues assures that all
partners are treated alike. They share proportionately in the gains as
well as the risks involved in the interstate enterprise.