Frederique Krupa
April 22, 1992The Evolution of the Telephone System:
From Bell's Electric Toy to the Internet
"Mr. Watson, come here. I want to see you."
A.G. Bell (SIT-126 & IC-122)
On March 10, 1876, Alexander Graham Bell first
transmitted speech electrically with an order to his assistant Thomas
A. Watson. Since then, the telephone -- or rather the telephone
system -- has revolutionized the way we live, socialize and do
business, but its ultimate potential was less than apparent to 19th
century society.
In fact, the technology was so radical that even the president
of Western Union, William Orton, had difficulty understanding
telephone's extraordinary possibility. When he was approached with
the option of buying Bell's patents for $100,000, he turned down the
opportunity to monopolize the entire electric communication industry
with the comment, "What use could this company make of an electric
toy." (SIT-16.)
To understand this lack of forecasting or unwise
bureaucratic caution, one has to understand that at the time the
telegraph dominated the communications industry. In 1876, 214,000
miles of telegraph wires carried over 31,703,181 messages delivered
through 8,500 telegraph offices. (SIT-18) Since the telegraph system
already had a fifty year lead over the telephone system, William Orton
could not see that telephony could combine the immediacy of the
telegraph, the potential for two-way person-to-person communication
and the psychological advantage of a human voice instead of cryptic
dots and dashes.
While social acceptance of the telephone has become
practically universal in slightly over a century since its invention, 19th
century society took at least a decade to fully understand the
invention and implement a useful system for the new technology. In
1876, Bell, a third generation speech specialist with a deaf wife and
mother, was busy working on a multiplexing device for the telegraph
system -- allowing simultaneous messages to be sent over the same
line at different frequencies, now called frequency division
multiplexing. This was the initial "harmonic telegraph" that gave Bell
the idea to explore the "speaking" telegraph. Elisha Gray was also
exploring harmonic multiplexing technology, but he continued to
apply his research to the telegraph system and could not make the
mental leap to an entirely new system of communication. Since Bell
approached telecommunications as an outsider, he was able to move
beyond the limitations of the current telegraph system, the downfall of
practical telegraph men like Orton or Elisha Gray (who might have
beat Bell's telephone patents by a year if he had seen its commercial
value). (SIT 147)
Bell and his backers had to invent uses for the telephone and
get the message across to the public. According to Bell's series of
experimental prototype telephones, it took Bell about six months to
design a two-way conversation model. Early telephone
advertisements show how the master uses a private line to
communicate with the servants, whether in the home or the factory.
Of course, the servants could now contact the master directly, a
significant social equalizer. (SIT-120)
In the mid to late 1870's, the public telephone
demonstrations that Bell took on the road -- to raise public
awareness, finance his work and appease his backers -- presented the
telephone as a broadcasting system, i.e. a radio-concept of telephony.
Watson would read the news from a nearby city, or for large venues,
professional musician and singers would entertain audiences
hundreds of miles away, over the telegraph lines. (Music was easier
to transmit because it was louder and could be significantly distorted
while remaining recognizable.) The telephone was often confused
with the telegraph in the mind of the public, and like the telegraph
before it, the phone system had to create a traffic of communication
that had not existed before.
If many people were confused about the telephone's
possibilities, Bell himself quickly formulated a prophetic vision of a
telephone system. He always saved the end of his demonstrations to
speak about the future of the telephone and spoke of a central office
system that would link up various phones through a "switch." On
March 25, 1978, he wrote in a letter to his British investors,
"It is conceivable that cables of telephone wires could be laid
underground, or overhead, communicating by branch wires with
private dwellings, country houses, shops, manufactories, etc.,
etc., uniting them through a main cable with a central office
where the wires could be connected as desired, establishing
direct communications between any two places in the city....Not
only so, but I believe in the future wires will unite the head office
of the Telephone Company in different cities, and a man in one
part of the country may communicate by word of mouth with
another in a different place." (SIT-22)
While he may have been correct in the long run, the first
phones that were installed were "private lines" that connected only
two telephones. Bell established commercial telephone service in
1877. By June 30, 1887 there were 230 phones installed; in July, there
were 750; and in August there were 1,300. (SIT-23) Within ten years,
167,000 phones would create a disorganized maze of overhead wires
in cities across the northeast. The early adopters of the telephone
were mostly businessmen who could afford to pay for the rather
expensive service. They were also the ones most likely to have been
using the telegraph and switched to the new, easier to use telephone
(which did not require a trained operator). Although domestic rates
for leasing a phone were approximately half those of businesses, ($20
versus $40 a year) they were still too expensive for working class
families. (SIT-27)
The switching system, signal boosters and multiplexing of
simultaneous calls over the same wire were adapted from the
telegraph system and made the growth of the telephone system
feasible. Gardiner Hubbard, Bell's influential backer and father-in-law
who later became head of AT&T, sold the rights to establish local
telephone networks for Bell Telephone Co. in the United States. The
first switchboard went into commercial service in 1878 with 21
subscribers in New Haven Connecticut, and in the 1880's they
sprouted up across the country. However, these local switchboards
would not be linked into a transcontinental system until 1914. Long
distance telephone service began in 1881 between Boston and Salem
and the system grew slowly after that: (IC-129)
1884 New York-Boston
1892 New York-Chicago
1893 Boston-Chicago
New York-Cincinnati
1895 Chicago-Nashville
1896 Kansas City-Omaha
New York-St. Louis
1897 New York-Charleston
New York-Minneapolis
New York-Norfolk, VA
1898 New York-Kansas City
(SIT-161)
INVENTION OF THE TECHNOLOGY
Bell's telephone was based on technology he was
developing for the telegraph. Instead of a having a switch like a
telegraph key which simply interrupts an electronic circuit, the
telephone sends electric signals whose current responds to the air
pressure of the original sound -- in this case, the human voice. Once
the voice passes into the transmitter, it changes into variable electric
current. This modulated current travels through copper wires to the
receiver. There, it drives an electromagnet which makes a diaphragm
vibrate, reproducing the original sounds. While it is hard to appreciate
this leap in technology from the telegraph, the telephone required the
simultaneous invention of the microphone (transmitter), signal
amplifiers and speaker (receiver).
Bell was obviously not the only inventor patenting new
technological breakthroughs that had telephone applications. Thomas
Edison provided two of the most important breakthroughs in early
telephone technology. He developed the frist commercially practical
transmitter and reciever. Edison had already invented multiplexing for
the telegraph in 1874 that allowed two messages to be sent in
opposite directions on the same line.
Bell's telephone could only carry a signal a very short
distance, 20 miles at most, so variable resistance transmitters that
would amplify the original signal had to be developed. In 1877,
Edison -- financially backed by Western Union intent on breaking the
Bell Telephone Co. monopoly by developing a phone not covered by
Bell's patents -- invented the first carbon microphone that modulated
an _existing_ current instead of _producing_ a varying current. The
carbon microphone could produce louder, cleaner signals. Bell tried
to contest the patents but failed. That same year, Edison invented the
loud-speaking receiver, a diaphragm driven by an electromagnet that
could transmit voices more clearly. Though Bell failed attempts to
contest Edison's patents, a compromise was reached that was to
repeat itself in subsequent years. These technological improvements
were bought out and incorporated by the Bell Telephone Co. (IC-124-
5)
Signal boosters to amplify fading signals as they traveled
through the copper wires made long distance telephone calls feasible.
A Belgian engineer, F van Rysselberghe, developed the anti-
interference "choke" in 1882. Multiplexing technology developed for
the telegraph was modified for the telephone. By the turn of the
century, 17 calls could be handled simultaneously on one copper wire.
This alleviated the need for individual copper phone lines between
each subscriber. One cable could handle the long distance calls of a
local network. Multiplexing helped to thin out the growing web of
overhead wires that were becoming a public nuisance in American
cities.
AT&T, incorporated in 1885, leased their phones to homes
and offices to maintain ownership and control over the technology --
which they continued to do until their break up in 1984. They initially
made their money solely on rental fees for the equipment, but soon
implemented a message rate for subscribers when AT&T almost went
bankrupt.
AT&T's success was actually based on a patent monopoly.
Endless legal battles were waged during the early years, especially
with Western Union (which was eventually bought out by AT&T).
Other inventors were quick to dispute Bell's telephone patents. Elisha
Gray filed his telephone patent hours after Bell but did not think his
invention was important enough to contest at the time. He quickly
grew to regret his decision and subsequently lost a ten year legal
battle. (HT 235) In any case, Gray's phone only transmitted sounds --
not voices -- through a weaker diaphragm. (IC-124) Philipp Reis, a
German inventor, had constructed a variable resistance transmitter in
1860, but he had failed to understand its telephony value. On Long
Island, Antonio Meucci had filed a patent for a telephone in 1871, but
it was simply an acoustic phone, like cups on a string. (IC-124)
INVENTION OF THE SYSTEM
The concept of the switchboard became prevalent in the
1880's, and as the system grew exponentially, the way calls were
routed had to become increasingly automated. At first, there was no
dial pad, no electronic switches, no signaling system. The caller
would crank a handle on the phone to call the local switchboard
operator who would connect the caller to the other party. If the call
was long distance, the operator would have to contact another
operator over an external line, then perhaps another, until the desired
party was reached.
In the first year of service, the signaling system underwent a
radical transformation. The first telephones did not have bells to
signal an incoming call. Subscribers would have to shout in the
mouthpiece or thump on it with a pencil, frequently breaking the
diaphragm. J.C. Watson developed the "thumper", then the "magento-
generator" which drove a "magneto-bell." The problem was that this
bell would ring indiscriminantly each subscriber's phone in the system
whenever a call was placed. The pressing need for an individual
signaling system became quickly apparent and was solved within the
first year of service. (HC 19-20)
The operator could easily listen in to any conversation, so
the personal nature of their service made the operator the town
message center. That is, at least until there were too many telephone
subscribers to be handled efficiently by operators. The first telephone
operators were undertrained, unsupervised telegraph boys but were
soon replaced by young women who proved to be more pleasant,
reliable and submissive. (HC 51-81)
The ever increasing number of callers soon transformed the
profession. By 1946, nearly a quarter-million young women were
employed by AT&T, but their numbers would soon dwindle due to the
implimentation of automatic call switching. Almon Stowger in 1889
invented the automatic switch to connect two parties without the aid
of an operator. An undertaker in Kansas City, Stowger suspected that
local operators were routing the calls to his rivals, so he wanted to cut
the women out of the calling process. The rotary dial -- which routes
a call via a set of switches activated by a series of pulse signals -- was
developed in 1900 but was not installed on a large scale until 1914 in
Newark, New Jersey. In 1921, Omaha, Nebraska opened the first all-
automatic exchange. By 1926, only 20 percent of the system used the
rotary dial and automatic switches. (SIT-272) Ironically, because
other countries were slower to install their telephone systems, they
were able to install automatic switchboards earlier than AT&T.
Direct dial long distance took a little longer to develop. The
first computerized switchboard was put into commercial service in
1976, and by 1982, half of all calls were switched electronically. The
electronic switchboards used tones to route calls. This was the origin
of touch tone keypad. (IC-138)
At the turn of the century, when Bell's 17 year patent
protection ran out, around 6000 independent phone companies sprang
up. These local switchboards would connect a few hundred
households but could not be linked to a national system. AT&T would
refuse to link these companies into their network monopoly and
would buy them out when they were on the verge of bankruptcy. (IC-
127)
AT&T, bought out in 1907 by New York Bankers like JP
Morgan, had effectively overwhelmed the independent telephone
companies and had over 7 million phones in their telephone system.
By 1930, there were 20 million subscribers. As technology improved
and the system became immense, calling costs went down. In 1927, a
three minute call from New York to London cost $75, took at least
eight operators and fourteen minutes to effect the connection. In
1945, the same call would cost $12 and take only 90 seconds to
effectuate, due to improvements in technology. (IC-124 and SIT-319)
This trend has been ongoing and now long distance calls cost a tiny
fraction of what it once did.
Many people were rather concerned about AT&T's
monopoly. AT&T agreed to Federal Communication Commission
regulation in 1956 in exchange for maintaining the status quo and
promising not to enter the emerging computer industry. The AT&T
monopoly lasted until a ten year lawsuit to break up the
telecommunication giant was settled in 1984. AT&T persuaded the
courts to let it get out of the local phone service industry in favor of
joining the deregulated long distance competition, where it believed
the real money was. AT&T got out of the local phones service and
seven "baby" bells were formed. The dissolution of AT&T also meant
that people could now own their telephones and freely hook up
peripheral devices such as faxes and modems.
TECHNOLOGICAL INNOVATION
The phone system installed before the 20th century used
twisted copper wires, called a loaded system. The cost of installing
copper wires took up one fourth of all of AT&T's budget in the late
19th century. Copper wires absorb a large amount of electrical energy
produced by the transmitter, which distorts the original quality.
Gradual improvement arrived that increased the quality of service and
calling capacity. Radio telephone links created the first long distance
service between England and the U.S. in 1927. Another major
improvement was coaxial cables in the 1940's that reduced
interference and increased calling capacity for the ever expanding
telephone system. Microwave stations in the 1950 (based on radar
technology) could carry almost 20,000 phone conversations. These
are still used to this day though mostly for broadcasting television
signals. Telecommunication satellites for transcontinental service
were soon added. In 1965, the first, named Early Bird, could carry
250 calls simultaneously. By 1976, the dozen or so newer
communication satellites could handle 30,000 calls each.
Digital transmission, i.e. the binary language of computers,
was introduced in 1962. In the old analog system, the electronic
signal in the wire looks like the sound waves in the air, which was
Bell's great breakthrough. In a digital system information _about_ the
soundwave -- not a _representation_ of it -- is sent over the wire.
Information about the amplitude of the speech is sampled thousands
of times a second, so that it can be reconstructed at the other end.
The system didn't really come into its own until the 1980's.
In 1970 Corning Glass developed the first fiber optics cable,
which uses laser light traveling through glass instead of electrons
traveling through copper. Laser light can be modulated at tremendous
rates, making possible a very high speed of transmission and an
information capacity 125,000 times that of a comparable copper wire.
(ME 77). In the last 20 years five different generations of fiber optics
systems were implemented, and industries wrote off billions of dollars
invested in microwave towers and copper cables. By 1980, it was
being used everywhere, on almost every intercity route and on many
local runs. (IC -138) The Achilles heel in this new system -- often
billed as the information superhighway -- is the old copper cables that
still lead into the vast majority of American homes. The only ones that
take advantage of digital transmission at this point are companies that
can afford to pay for the installation of expensive high-bandwidth
phone lines and high speed switching systems.
Estimates for rewiring every household in the U.S. with fiber
optic cables has been estimated at $100-325 billion. In New Jersey
alone, this effort requires the replacement of 56.3 million mile of
copper. (IC 158-9) This has created a strong interest in developing
technology for old lines, in the form of digital service, fiber optics and
signal compression. I.S.D.N -- short for Integrated Service Digital
Networks-- promise to make the entire phone system digital. The
local network is analog due to low capacity copper wires, but signal
compression technology might just make I.S.D.N. a possibility
without rewiring every home with fiber optics. The eight NYNEX
employees I spoke to recently had never have heard of I.S.D.N., so it
would be foolish to speculate just when this service might be
available.
BEYOND THE TELEPHONE
The phone system transmits much more than just voice
conversations these days, with the use of faxes and modems. Faxes
scan a document, encodes the pattern of light and dark into digital
signals and sends those signals over the phone lines with a built in
modem. Modems convert the digital information (binary codes
composed of 0 and 1s) into an analog signal that can be sent over the
regular phone line. The receiving modem demodulates the analog
signal back to a digital signal. On the receiving end of a fax machine,
the modem converts back to digital signals that is then printer out,
usually on thermosensitive paper.
IBM and the Air Force were working on the SAGE defense
system and invented modems (MOdulate DEModulate) in the 1950's
to allow computers to start talking to each other. Modems did not
come into popular use until the popular in the 1970s. (IC-148)
Automatic Teller Machines (ATMs) that use modems and high-
bandwidth telephone lines appeared in the early 1970's. By 1981,
there were 26,000 of them. (IC 151)
As for the fax machine, the first patented facsimile
transmission was in England in 1843 by Alexander Bain. The French
produced the first commercial facsimile system in 1865. The systems
were too slow to serve any use, so there were few fax applications. In
the 1930's, a few newspapers used radio facsimile to file stories, but
they didn't last. In the 1950's, Western Union developed a fax system
but only for internal use. In 1966, the XEROX Telecopier I hit the
market. It could transmit a page of text in 4-6 minutes, and, not
surprisingly, XEROX only sold 5,000 units per year. The 1970's and
1980s saw fax machine prices go down. An international fax standard
was developed by Nippon Telephone & Telegraph. Because of the
Japanese language has thousands of characters -- requiring
typewriters and computer keyboards that look like typesetting
equipment, recently commented upon by Nicholas Negroponte in
Wired-- they found the fax that could transmit handwritten messages
particularly useful. Fax machines became much faster and cheaper
and sales took off. 100,000 fax machines were sold in 1983, 200,000
were sold in 1986 and 2 million in 1991. That year, 17 billion pages
were transmitted by 6 million fax machines and 1.1 million
fax/modems. (IC 152)
Besides the fax and modem, cellular phone technology has
allowed for mobile telecommunication. This is, naturally, being
adapted for mobile computer applications as well. Cellular phones
appeared in the early 1980's. 1 million cellular phones were in service
in 1987 and quickly jumped to 9 million in 1992. Cellular phone
networks use the regular telephone system that is connected to a
computer control center and transmission towers. Computers control
the amount of the radio spectrum needed to serve the customers.
Available frequencies are allocated to ensure that all calls can be
handled when a phone is activated. This is based on the assumption
that not all the phones will be used at any one time. Two well
publicized ventures in the future of portable telecommunication are
the satellite networks being developed by giants like Motorola, TCI
and Microsoft. (IC 159.)
The telephone has potential to take advantage of the
information superhighway, by helping people transmit and receive
digital information over computer networks. In Paris, there is a
government sponsored on-line service called Minitel -- provided free
of charge -- by the state-owned French Telephone company. A very
basic , very ugly one-piece computer terminal hooked up with a
modem allows 6 million Parisians to get directory assistance, order
plane tickets, find a date, etc... The user pays for the calls, and since
the calls are by the minute, the phone company allows the Minitel
users to rent better equipment with faster modems.
In the US, all these types of service are provided by private
corporations on a for-profit basis. Potential users must supply their
own computer system to take advantage of the online services, that
come via their modem, personal computer and phone line. Calling up
a local access number allows a hook up to a local network so the
users only pay for the cost of a local call. This local network is then
hooked into a national network. In most cases, a monthly
membership fee allows a member of an online service to send e-mail
to anyone with an electronic account, to obtain information from
digital databases and newsgroups, and converse with people from all
over the country or even the world. While this allows more flexibility
and innovation than a state-funded monopoly, it is much easier to
exclude the disenfranchised from a new "public" forum -- those that
might not be able to afford computer equipment and membership fees.
The Internet, the closest we come to a government
sponsored Infobahn, began as a network named ARPAnet linking
government, university and defense research facilities. The Internet is
now an international system of over 17,000 networks in 33 countries
and is being tapped into by commercial firms that allow anyone to
explore the system. (WI-11-5)
CONCLUSION
The history of the telephone system has been as much about
an evolution of communication policies than about an evolution of
technology. The telephone system was built to take advantage of a
technology that had no clear use at the time of its invention. Its
potential has radically expanded recently with the computer networks
and fax machines. We could not imagine life without the telephone
system and have a hard time understanding why its potential was
such a mystery over a century ago.
As stated before, Bell and his backers were quite astute at
forecasting the commercial potential of the telephone. They were
intelligent men who specialized into developing branches of rank 3
technology. Bell and company fit in neatly with other late rank 3
inventors such as Edison, Morse, Ford. They were the first to
combine scientific knowledge with a keen capitalist business sense.
These practical technologists as Ithiel de Sola Pool calls them, "...
were interested not only in what might be theoretically possible but in
what would sell; the optimism of their speculation was controlled by a
profound concern for the balance sheet." (SIT 129). Just as likely
though, they were successful forecasters because they were in in a
position to fulfill their own predictions. They had the patents, the
vision and the financial backing to implement it, but this only worked
if the first set of criteria -- intelligence, science and capitalism -- have
been met.
Trevor Williams mentions that the first rank 3 inventors
were not particularly educated, as exemplified by the inventors of the
steam engine. Thomas Newcomen was an ironmonger's apprentice,
James Watt was a carpenter's son and his partner Thomas Boulton
was the son of a buckle manufacturer. Even Josiah Wedgewood, the
famous ceramist, began work at nine. Bell, Edison, Morse and Gray
were much more educated in comparison to them, but they had the
same basic education that a contemporary high school (honors?)
student might have. Rank 4 inventors for the most part are highly
educated and specialized researchers in universities or corporations.
But I would like to suggest that Bell was one of the early
rank 4 thinker in a rank 3 world for making such a large mental leap --
with a coherent vision of a universal communication system that had
never exited before. The technology he envisioned had to be built and
had to create communication traffic for itself.
The profound effects the telephone system has had on
society, altering the way we work, socialize and -- McLuhan might
argue -- think, has been frequently written about. I would venture to
say that the telephone system was the first communication technology
for rankshift from 3 to 4. The telephone is everywhere and nowhere. It
is credited for being the first technology to make distances shrink
with its instantaneous two-way transmission. Sure, the telegraph and
the train came before, but the train was a just a mode of
transportation. A telegraph was just a note that was delivered the
same day -- a faster, more impersonal mail service. Only the phone
allowed two people to be in two places at once. Its extraordinary
power to alter our concept of space and time is now a common
experience for much of the world. Its system is being tapped by other
technologies, most notably computers, and will be a major part of the
much awaited Information Superhighway. As Karrie Jacobs says,
"The highway metaphor suggests something well organized,
something that is by definition linear. This is the beauty of the
phrase. It is seductive because it so effectively conceals chaos. It
hides the fact that what is really happening is that all our existing
sources of information... are being thrown into a blender and no
one knows what will emerge..." (ME 78)
The system of wires that will supply us with this chaos has its roots in
rank 3, but its potential will be fully explored in rank 4. Bell had no
way of knowing about the Internet, but as Paul Westlake mentioned,
"Bell's thinking was closer to rank 4 than the people he tried to
introduce and sell the phone to." (N112)
While Bell may have been like other late rank 3 inventors
mastering rather straight forward technology and capitalist know-how
--the kind invention no longer feasible today due to the complex
nature of current technological advancements -- the telephone system
itself is pure rank 4. Unlike the steam engine, the car or the loom, the
telephone has not reached its peak yet. It is an ever expanding, ever
changing system that is more chaotic than linear, with overlapping
levels of technology such as fiber optics co-existing with the old
copper wires. Unlike the telegraph system that has virtually
disappeared, the telephone system has no physical limitations. It can
continue to change as our needs change. Bell realized its radical
potential for a universal system but was still limited by the
technological capabilities at the time. Bell should be one of the first
rank 4 thinkers, a small curve up in rankshift when rank 3 was barely
a plateau.
BIBLIOGRAPHY
Bell, Alexander G.; _The Bell Telephone_; Boston, Amercain Bell
Telephone Co., 1908. (BT)
Brooks, John; _Telephone: The First Hundred Years_; New York,
Harper's & Row, 1976. (TFH)
Gorman, Michael; "Alexander Graham Bell, Elisha Gray and The
Speaking Telegraph;" _History of Technology_: Vol. 15;
Mansell Pub. Ltd, 1993. (HOT)
Hays, David G.; _The Evolution of Technology_; White Plains, NY,
Connected Education, 1991. (ET)
Jacobs, Karrie; "Waiting for the Millenium: The Box;" _Metropolis;
May 1994, pg.76. (ME)
Kroll, Ed; _The Whole Internet_; Sebastopol, CA, O'Reilly &
Associates, 1993. (WI)
Lubar, Steven; _Infoculture_; New York, Houghton, Mifflin
Company, 1993. (IC)
Lupton, Ellen; _Mechanical Brides: Women and Machines from
Home to Office_; New York, TK, 1992. (MB)
Martin, Michele; _Hello, Central?_; Montreal, McGill-Queen's
University Press, 1991. (HC)
McLuhan, Marshal; _Understanding Media_; New York,
McGraw Hill, 1965. (UM)
Negroponte, Nicholas; "The Fax of Life"; _Wired_; April 94, pg. 144.
Ronnel, Avital; _The Telephone Book: Technology, Schizophrenia,
Electric Speech_; Lincoln, University of Nebraska Press,(TB)
Pool, Ithiel de Sola; _The Social Impact of the Telephone_;
Cambridge, MIT Press, 1977. (SIT)
Wasserman, Neil H.; _From Invention to Innovation_; Baltimore,
John Hopkins University Press, 1985. (II)
Williams, Trevor; _History of Technology_; New York, Facts on File, (HT)
Young, Peter; _Person to Person: The International Impact of the
Telephone_; Camridge, England, Granta Editions,(PTP)
From the Enlightenment to the Industrial Revolution ||| Ethics and Technology ||| History of Materials ||| McLuhan ||| History of Human Factors
Frederique Krupa ||| Urbanism Papers ||| Architecture Papers ||| Design & Technology Papers ||| Home