G. W. Pierce
Encyclopedia
George Washington Pierce (January 11, 1872 - August 25, 1956) was an American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

. He was a professor of physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

 at Harvard University
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...

 and inventor in the development of electronic telecommunication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...

s.

The son of a Texas cattle rancher, he distinguished himself in school at Taylor
Taylor, Texas
Taylor is a city in Williamson County, Texas, United States. The population was 13,575 at the 2000 census; it was 15,191 in the 2010 census estimate. Taylors largest employers include the Electric Reliability Council of Texas , Durcon Inc, and the T. Don Hutto Residential Center, an immigration...

 and in the University of Texas before beginning his enduring relationship with Harvard in 1898. He wrote three innovative texts, many learned papers, and was assigned 53 patents. The most notable is the single-stage crystal oscillator
Crystal oscillator
A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency...

 circuit, which became the touchstone of the electronics communication art. Süsskind says that he was “an exceedingly warm and droll individual, much revered by his students.”

Youth

G. W. Pierce was born January 11, 1872, in Webberville, Texas
Webberville, Texas
Webberville is a village in Travis County, Texas . Its population was 336, according to a 2008 census estimate.Comprising settlements dating back to 1827, Webber's Prairie was formally established by retired physician John Ferdinand Webber in 1839...

. He frequently recalled in later life “drawing water with leaky buckets from deep wells for thirsty mules” as a prod that motivated his intensity in study. At the University of Texas he had Alexander Macfarlane
Alexander Macfarlane
Alexander Macfarlane was a Nova Scotia lawyer and political figure. He was a member of the Canadian Senate from 1870 to 1898. His surname also appears as McFarlane in some sources....

 as teacher and mentor: they co-authored a paper for the first volume of the Physical Review
Physical Review
Physical Review is an American scientific journal founded in 1893 by Edward Nichols. It publishes original research and scientific and literature reviews on all aspects of physics. It is published by the American Physical Society. The journal is in its third series, and is split in several...

. He taught at Dallas High School (1896-7) and worked in the clerk’s office of the Bastrop County
Bastrop County, Texas
Bastrop County is a county located in the U.S. state of Texas. As of 2006, the population was 71,700. Its county seat is Bastrop. Bastrop County is named for Felipe Enrique Neri, Baron de Bastrop , an early Dutch settler who assisted Stephen F...

 Court before winning his 1898 scholarship to Harvard. With a thesis on measurement of wavelength of shortwaves he gained the Ph.D. in 1900. After a European study-tour that included some exposure to Ludwig Boltzmann
Ludwig Boltzmann
Ludwig Eduard Boltzmann was an Austrian physicist famous for his founding contributions in the fields of statistical mechanics and statistical thermodynamics...

, he was invited to begin instructing at Harvard. He was instrumental in forming the Wicht Club (1903–1911), a peer-group dedicated to continuing their learning even though teaching.

Family

G. W. Pierce was the middle son of three. He shared his name with his father, but there seems to have been no need for the traditional Sr and Jr appendages. In 1904 he married Florence Goodwin of Saxonville, Massachusetts
Saxonville, Massachusetts
Saxonville is a historic mill village located in the north end of the town of Framingham, in Middlesex County, Massachusetts 01701.- Geography :Saxonville is located at 42.3203 degrees latitude, 71.4404 longitude....

. Though they produced no progeny they enjoyed some family life with Cornelia and Walter Cannon
Walter Bradford Cannon
Walter Bradford Cannon, M.D. was an American physiologist, professor and chairman of the Department of Physiology at Harvard Medical School. He coined the term fight or flight response, and he expanded on Claude Bernard's concept of homeostasis...

, Harvard Medical School physiologist, who attracted the Pierces to Franklin, New Hampshire
Franklin, New Hampshire
The median income for a household in the city was $34,613, and the median income for a family was $41,698. Males had a median income of $32,318 versus $25,062 for females. The per capita income for the city was $17,155...

. For example, Cornelia got George into portrait, landscape, and abstract painting. This medium became a strong method of expression for him. After Florence passed in 1945, Pierce found a second companionship with Helen Russell of Sanbornton, New Hampshire
Sanbornton, New Hampshire
Sanbornton is a town in Belknap County, New Hampshire, United States. The population was 2,966 at the 2010 census. It includes the villages of North Sanbornton and Gaza.-History:...

. The first sign of faltering came with a minor stroke in 1945, but he carried on until a major series killed him a decade later. He died August 25, 1956.

Professor / Inventor

G. W. Pierce had an eye for finding the main sticking point in physical processes. For electronics he saw that resonance
Resonance
In physics, resonance is the tendency of a system to oscillate at a greater amplitude at some frequencies than at others. These are known as the system's resonant frequencies...

 was a key phenomenon. His five part series “Experiments on resonance in wireless telegraph circuits” in the Physical Review (1904-7) are evidence of his leadership. By 1910 his first textbook Principles of Wireless Telegraphy was published. It is in this text, and others by John Ambrose Fleming
John Ambrose Fleming
Sir John Ambrose Fleming was an English electrical engineer and physicist. He is known for inventing the first thermionic valve or vacuum tube, the diode, then called the kenotron in 1904. He is also famous for the left hand rule...

, that the term modulation
Modulation
In electronics and telecommunications, modulation is the process of varying one or more properties of a high-frequency periodic waveform, called the carrier signal, with a modulating signal which typically contains information to be transmitted...

 is first used to describe imprinting an audio wave onto a high-frequency carrier wave
Carrier wave
In telecommunications, a carrier wave or carrier is a waveform that is modulated with an input signal for the purpose of conveying information. This carrier wave is usually a much higher frequency than the input signal...

 by variation of amplitude of the carrier (see Sarkar et al. 2006). In 1912 he worked with A. E. Kennelly on motional impedance (see below). In 1914 he was assigned the directorship of the Cruft Physics Laboratory at Harvard. Then in 1917 he gained the rank of full professor.

The year 1920 saw two important developments: his second text Electric Oscillations and Electric Waves was published. And most significantly, he followed up on an innovation of Walter Guyton Cady
Walter Guyton Cady
Dr. Walter Guyton Cady was a noted American physicist and electrical engineer. He was a pioneer in piezoelectricity, and in 1921 developed the first crystal oscillator....

 of Wesleyan University, using quartz crystal to stabilise frequency of electrical oscillation. In early attempts, radio communication was severely handicapped by the lack of reliable fixed-frequency operation, and Pierce saw the potential for the quartz-governed circuit. Cady’s circuit used multiple triode vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...

s, and Pierce was able to reduce this to a single tube (see B. Parzen, 1983). Insights such as this one resulted in patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....

 assignments, for which Pierce then sold license to use, yielding him the capital to purchase vacation homes in Franklin, New Hampshire, and St. Petersburg, Florida
St. Petersburg, Florida
St. Petersburg is a city in Pinellas County, Florida, United States. It is known as a vacation destination for both American and foreign tourists. As of 2008, the population estimate by the U.S. Census Bureau is 245,314, making St...

.

Motional impedance

In their laboratory, Pierce and A. E. Kennelly undertook an experiment measuring the change in impedance
Electrical impedance
Electrical impedance, or simply impedance, is the measure of the opposition that an electrical circuit presents to the passage of a current when a voltage is applied. In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current circuit...

 of telephone
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...

 receivers over a range of audio frequencies when the diaphragm was clamped by finger or quill insert. At each frequency the receiver resistance
Electrical resistance
The electrical resistance of an electrical element is the opposition to the passage of an electric current through that element; the inverse quantity is electrical conductance, the ease at which an electric current passes. Electrical resistance shares some conceptual parallels with the mechanical...

 and reactance were measured and impedance computed, then the difference of free versus clamped impedance plotted as a complex number, or point in the impedance plane. For every receiver, the range of frequencies yields a series of con-cyclic points. The phenomenon was called "motional impedance" and the circle a "motional impedance circle". Their paper is a model of clarity in exposition: see GWP and AEK, Proceedings of the American Academy of Arts and Sciences 48:113-51 (1912). This example of circular phenomena in device-impedance became so familiar, eventually, that the Smith Chart
Smith chart
The Smith chart, invented by Phillip H. Smith , is a graphical aid or nomogram designed for electrical and electronics engineers specializing in radio frequency engineering to assist in solving problems with transmission lines and matching circuits...

 was introduced to provide a bounded universe (or chart) for such circles.

Later years

In 1921 he was made Rumford Professor of Physics; in 1929 he was awarded the Medal of Honor
IEEE Medal of Honor
The IEEE Medal of Honor is the highest recognition of the Institute of Electrical and Electronics Engineers . It has been awarded since 1917, when its first recipient was Major Edwin H. Armstrong. It is given for an exceptional contribution or an extraordinary career in the IEEE fields of...

 of the Institute of Radio Engineers
Institute of Radio Engineers
The Institute of Radio Engineers was a professional organization which existed from 1912 until January 1, 1963, when it merged with the American Institute of Electrical Engineers to form the Institute of Electrical and Electronics Engineers .-Founding:Following several attempts to form a...

. He continued to acquire patents and reported on crystal oscillator
Crystal oscillator
A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency...

s in the Proceedings of the American Academy of Arts and Sciences
American Academy of Arts and Sciences
The American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...

in 1923 and 1925. He retired in 1940, publishing his text Song of Insects in 1943. It made an analysis of the cricket
Cricket (insect)
Crickets, family Gryllidae , are insects somewhat related to grasshoppers, and more closely related to katydids or bush crickets . They have somewhat flattened bodies and long antennae. There are about 900 species of crickets...

 “song”. In same year the
lin Institute awarded him its Franklin Medal
Franklin Medal
The Franklin Medal was a science and engineering award presented by the Franklin Institute, of Philadelphia, PA, USA.-Laureates:*1915 - Thomas Alva Edison *1915 - Heike Kamerlingh Onnes *1916 - John J...

.

For a list of publications and patents see Saunders and Hunt (1959).
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