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http://en.wikipedia.org/wiki/Nathan_Stubblefield
Inventions
Bob Lochte (2001) has argued that when Stubblefield spoke
of "wireless" telephony in the 1880s he merely meant his acoustic
telephone, which could operate with string. However, in the 1880s, Scientific American
had already carried articles describing attempts at wireless telephony
and telegraphy experiments by induction systems of Trowbridge, Preece,
Phelps, and Edison, not using high frequency radio waves, so
Stubblefield was likely familiar with all the principles needed to
operate wireless telephony by induction in the 1880s. He made
private demonstrations of wireless telephony in 1892. Rainey T. Wells
was one of the first persons to hear Stubblefield's wireless voice
transmissions, in that year. Wireless telegraphy using damped high frequency radio waves was demonstrated in 1894 by Sir Oliver Lodge, but that system could not carry voice messages or music. In 1898, Stubblefield was issued U.S. Patent 600457 for an "Electric battery,"
which was an electrolytic coil of iron and insulated copper wire to be
immersed in liquid or buried in the ground, where it could also serve as
a ground terminal for wireless telephony.
http://www.nathanstubblefield.com/contents.html
Wireless in 19th Century America -
Beginning with Morse's 1842 experiments, American inventors including
Bell and Edison confront the challenge of wireless telegraphy and
telephony with limited success. By 1891, most of them have abandoned
their efforts.
"Hello, Rainey." - In 1892, ignorant of
the wireless inventions of the past 60 years, Nathan creates an
electromagnetic induction wireless telephone and demonstrates it to his
friend Rainey Wells. A few years later, Nathan develops a superior
wireless telephone that uses natural conduction through the earth and
water.
The Wireless Telephone Company of America
- After a well-publicized public demonstration of his wireless
telephone on New Years Day 1902 in Murray, including its broadcasting
capabilities, Nathan's work attracts national attention. He follows this
event with a demonstration in Washington DC, where he makes a ship to
shore telephone call, and eventually accepts an offer of cash and stock
to sell his invention to the Wireless Telephone Company of America. The
company sends Nathan and his eldest son Bernard to Philadelphia and then
New York to demonstrate the system for wealthy potential investors. The
first presentation is successful, but the New York demonstration is a
failure. Nathan returns to Murray to expose the company as a fraudulent
stock promotion scheme.
...
Ada Mae, Pattie, and Nathan Stubblefield (l. to r.) with portable wireless telephone receiver, 1907
http://earlyradiohistory.us/1902stb.htm
Scientific American, May 24, 1902, page 363:
THE LATEST ADVANCE IN WIRELESS TELEPHONY.
BY WALDON FAWCETT.
The
latest and one of the most interesting systems of wireless
communication with which experiments have recently been conducted is the
invention of Nathan Stubblefield, of Murray, Ky., an electrical
engineer who is the patentee of a number of devices both in this country
and abroad. The Stubblefield system differs from that originated by =
Marconi in that utilization is made of the electrical currents of the
earth instead of the ethereal waves employed by the Italian inventor,
and which, by the way, it is now claimed, are less powerful and more
susceptible to derangement by electrical disturbances than the currents
found in the earth and water. In this new system, however, as in that
formulated by Marconi, a series of vibrations is created, and what is
known as the Hertzian electrical wave currents are used.
The key to the methods which form the basis of all
the systems of wireless telephony recently discovered--the fundamental
principles of wireless telephony, as it were--was discovered at
Cambridge, Mass., in 1877 by Prof. Alexander Graham Bell, the inventor
of the telephone system which bears his name. On the occasion mentioned
Prof. Bell was experimenting to ascertain how slight a ground connection
could be had with the telephone. Two pokers had been driven into the
ground about fifty feet apart, and to these were attached two wires
leading to an ordinary telephone receiver. Upon placing his ear to the
receiver, Prof. Bell was surprised to hear quite distinctly the ticking
of a clock, which after a time he was able to identify, by reason of
certain peculiarities in the ticking, as that of the electrical
timepiece at Cambridge University, the ground wire of which penetrated
the earth at a point more than half a mile distant.
Some five years later Prof. Bell made rather extensive experiments
along this same line of investigation at points on the Potomac River
near Washington, but these tests were far from satisfactory. It was
found on this occasion that musical sounds transmitted by the use of a
"buzzer" could be heard distinctly four miles distant, but little
success was attained in the matter of communicating the sound of the
human voice. Meanwhile Sir William Preece, of England, had undertaken
experimental study of the subject of wireless telephony, and during an
interval when cable communication between the Isle of Wight and the
mainland was suspended, succeeded in transmitting wireless messages to
Queen Victoria at Osborne by means of the earth and water electrical
currents.
Mr. Stubblefield's experiments with wireless
telephony dated from his invention of an earth cell several years ago.
This cell derived sufficient electrical energy from the ground in the
vicinity of the spot where it was buried to run a small motor
continuously for two months and six days without any attention whatever.
Indeed, the electrical current was powerful enough to run a clock and
several small pieces of machinery and to ring a large gong. Mr.
Stubblefield's first crude experiments looking to actual wireless
transmission of the sound of the human voice were made without ground
wires. Nevertheless, by means of a cumbersome and incomplete machine,
without an equipment of wires of any description, messages were
transmitted through a brick wall and several walls of lath and plaster.
As the development of the system progressed, the present method of
grounding the wires was adopted, in order to insure greater power in
transmission.
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The apparatus which has been used in the most recent
demonstrations of the Stubblefield system, and which will be installed
by the Gordon Telephone Company, of Charleston, S. C., for the
establishment of telephonic communication between the city of Charleston
and the sea islands lying off the coast of South Carolina, consists
primarily of an ordinary receiver and transmitter and a pair of steel
rods with bell-shaped attachments which are driven into the ground to a
depth of several feet at any desired point, and which are connected by
twenty or thirty feet of wire to the electrical apparatus proper. This
latter consists of dry cells, a generator and an induction coil, and the
apparatus used in most of the experiments thus far made has been
incased in a box twelve inches in length, eight inches wide and eighteen
inches in height. This apparatus has demonstrated the capability of
sending out a gong signal as well as transmitting voice messages, and
this is, of course, of great importance in facilitating the opening of
communication.
The most interesting tests of the Stubblefield system
have been made on the Potomac River near Washington. During the land
tests complete sentences, figures, and music were heard at a distance of
several hundred yards, and conversation was as distinct as by the
ordinary wire telephone. Persons, each carrying a receiver and
transmitter with two steel rods, walking about at some distance from the
stationary station were enabled to instantly open communication by
thrusting the rods into the ground at any point. An even more remarkable
test resulted in the maintenance of communication between a station on
shore and a steamer anchored several hundred feet from shore.
Communication between the steamer and shore was opened by dropping the
wires from the apparatus on board the vessel into the water at the stern
of the boat. The sounds of a harmonica played on shore were distinctly
heard in the three receivers attached to the apparatus on the steamer,
and singing, the sound of the human voice counting numerals, and
ordinary conversation were audible. In the first tests it was found that
conversation was not always distinct, but this defect was remedied by
the introduction of more powerful batteries. A very interesting feature
brought out during the tests mentioned was found in the capability of
this form of apparatus to send simultaneous messages from a central
distributing station over a very wide territory.
Extensive experiments in wireless telephony have also
been made by Prof. A. Frederick Collins, an electrical engineer of
Philadelphia, whose system differs only in minor details from that
introduced by Mr. Stubblefield. In the Collins system, instead of
utilizing steel rods, small zinc-wire screens are buried in the earth,
one at the sending and another at the receiving station. A single wire
connects the screen with the transmitting and receiving apparatus,
mounted on a tripod immediately over the shallow hole in which the
screen is stationed. With the Collins system communication has been
maintained between various parts of a large modern office building, and
messages have been transmitted without wires across the Delaware River
at Philadelphia, a distance of over a mile.