Topics in the News
Aviation in the United States began with the enthusiasm for ballooning in the years before the Civil War. There were some three thousand balloon ascents by 1859. Both the Union and Confederate armies used balloons for reconnaissance during the war. The Union effort, headed by Thaddeus Lowe, used tethered balloons to observe enemy movements which were then telegraphed to field officers. At the Saint Louis Exhibition of 1904 prizes that were offered for navigable airships drew ninety-seven entrants with dirigibles and similar machines. One of these was Roy Knabenshue, who piloted a sixty-two-foot dirigible over New York City in 1905. A second airship competition held in Saint Louis in 1907 again reflected the national fascination with large airships. Many Americans believed that dirigibles held the key to future air travel.
The major precursor of American aeronautical engineering was Samuel P. Langley, director of the Smithsonian Institution, who in 1891 asserted, "Mechanical flight is possible with engines we now possess." Beginning in 1887 he had experimented with large model airplanes (weighing as much as thirty pounds), using twisted-rubber motors in order to test various wing designs. He eventually settled on a tandem model with two sets of wings, one behind the other, with twin propellers in between....
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Vivisection and Experimental Medicine.
Virtually all advances in physiology and endocrinology in the late nineteenth and early twentieth centuries were based on vivisection—the experimental use of living animals to observe physiological processes under laboratory conditions. The most successful forms of vivisection began with the French physiologist Claude Bernard, who discovered the liver's glycogenic function by severing a rabbit's cerebellar peduncle nerve and noting the abnormally high levels of sugar (glycosuria) that resulted. In endocrinology at the turn of the century, the chemical actions of the ductless glands were studied by extirpating the gland and observing the resultant metabolic changes in the animal subjects. The procedure led in 1901 to the isolation of adrenaline (epinephrine) by Japanese American chemist Jokichi Takamine and Johns Hopkins Medical School chemistpharmacologist John Jacob Abel.
Organized Opposition to Vivisection.
The rise of the movement to curtail the experimental use of animals paralleled the successes of vivisection and advances in physiology, pathology, and bacteriology in the third quarter of the nineteenth century. In England an Antivivisection Act was passed by Parliament in 1876. In 1883 the American Antivivisection Society was founded in Philadelphia. Such societies joined with state chapters...
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Astronomy: 1905 Solar Eclipse
Photography and Eclipse Observations.
Since the middle of the nineteenth century solar eclipses had attracted intense interest among astronomers. The invention of photography and its application to astronomical observations made it possible to record with great precision the solar phenomena that eclipses revealed. Although some primitive daguerreotype photographs had been made of both the sun and the moon in the 1840s, the crucial break-through came with Englishman Warren de la Rue's invention of the photoheliograph, a photographic telescope with a fast shutter that could be used to map the surface of the sun.
The first significant riddle that astronomical photography resolved concerned the existence of solar prominences, protuberances from the sun's outer edge that had long puzzled astronomers. It was not clear whether they were physical features of the sun or merely optical illusions. De la Rue took his photoheliograph to Spain, which offered the best view of the solar eclipse of 1860, an event that attracted many European astronomers, including Angelo Secchi, the second pioneer of photographic astronomy. Secchi compared his observations with de la Rue's photographs and confirmed that the prominences seen during the eclipse were real.
The Eclipse of 1905.
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The Invention of the Automobile.
Although some steam-driven vehicles were built in England, France, and the United States in the early nineteenth century, the
Born on a farm in Dearborn, Michigan, in 1863, Henry Ford saw his first horseless carriage (a steam-driven one) at the age of twelve and never forgot the tremendous impression it made on him. His earliest automotive projects were aimed more at developing a practical tractor than a pleasure vehicle. Ford established...
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Biology: Beginnings of Bioengineering
Scientific interest in bioengineering preceded the late-twentieth-century interest in biotechnology that is centered on genetics and on the possibility of altering the genetic makeup of cells and organisms. The early history of bioengineering in the United States is associated with Jacques Loeb. Born in Germany in 1859, Loeb immigrated to the United States in 1891, where he taught biology at the Universities of Chicago and California and from 1910 until his death in 1924 at the Rockefeller Institute.
Loeb and Parthenogenesis.
Parthenogenesis is the process whereby an egg is induced to develop into an organism without having been fertilized. Both Loeb and Thomas Hunt Morgan, the most prominent American geneticist, had experimented with sea urchin eggs. Morgan had induced them to segment by immersing them in a solution of inorganic salts, although they failed to produce larvae. Loeb, using a variation of the same procedure, was able to raise larvae, a result he announced in 1899. The news caused a sensation, and Loeb was a finalist for the first Nobel Prize in physiology, awarded in
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Biology: Mendelian Genetics
Mendel and His Rediscovery.
Gregor Mendel was an Austrian monk who, as a result of experimentation in plant hybridization between 1856 and 1863, discovered that certain parental characteristics are dominant in the next generation and others are what he called recessive (that is, they do not appear but can be passed on to the next generation). Moreover, he found that such parental traits segregate themselves in a precise numerical ratio. Thus, if A represents a dominant round seed shape and a a recessive angular shape, then one-quarter of the progeny will have the dominant (AA), one-quarter the recessive (aa), and one-half will have a dominant and a recessive (Aa or aA), what is now called a heterozygous combi-nation. Mendel's work was scarcely noted at the time. It was not until 1900 that three European biologists, Hugo de Vries, Karl Correns, and Erich von Tschermak independently rediscovered Mendel's "principle of segregation." In 1909 the Danish biologist Wilhelm Johannsen coined the terms that became standard: gene to represent the unit of heredity, genotype to designate the genetic makeup of an organism, and phenotype to denote the actual appearance of the organism.
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Einstein's Special Theory of Relativity
A New Idea.
The German Jewish theoretical physicist Albert Einstein formulated the special theory of relativity in 1905. Relativity is that area of physics that has to do with how observers in motion with respect to the phenomenon observed can account for their observations given that two different frames of reference (that of the observer and that of what is observed) are involved. Einstein labeled his 1905 theory "special" because it dealt with a limited range of phenomena, namely uniform linear motion at constant but high velocities. The consequences of special relativity became cornerstones of twentieth-century physics and displaced some of the central tenets of Newtonian physics that had been pillars of scientific thought for two centuries.
First, Einstein showed that time, space, and matter are interdependent, as expressed in the famous formula e - mc2 , where e is energy, m is mass, and c is the speed of light. The mass of material objects is determined by their energy; if they give off energy, their mass decreases. Mass increases with velocity and since the velocity of light is so great, a small mass traveling at the speed of light is equivalent to a vast
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Freud Comes to America
A New Approach to Psychology.
Sigmund Freud, an Austrian Jewish psychiatrist who fashioned a dynamic theory of psychology of human behavior based on the workings of the unconscious mind, achieved world prominence by virtue of his highly publicized visit in September 1909 to Clark University in Worcester, Massachusetts. Clark had built a strong psychology program under president and leading psychologist G. Stanley Hall, who invited Freud to lecture as part of the festivities celebrating the twentieth anniversary of the university's founding. Freud's trip to Clark was his only trip to the United States.
Freud had first set forth his concepts of psychoanalysis in his famous book On the Interpretation of Dreams, published in German in 1900. He explained how conscious thoughts—particularly those that are unpleasant or threatening—are repressed, only to reappear in a person's unconscious mind where they are revealed, in distorted form, in dreams. The analysis of first his own and then his patients' dreams gave Freud a key to understanding how the unconscious works—specifically by mechanisms of repression, wish fulfillment, condensation (whereby one word or image replaces another similar one: the origin of most "Freudian slips"), and displacement (the exaggeration of unimportant details, which gives dreams their...
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Radio waves were discovered in 1887 when the German physicist Heinrich Hertz produced electromagnetic waves from an oscillating circuit connected to an induction coil. The waves traveled with the speed of light and could be detected (that is, received) with a simple wire loop. "Hertzian waves," as they came to be called, were promptly studied by physicists in laboratories around the world. One of these experimenters, the Italian Augusto Righi, introduced the phenomenon to his friend Guglielmo Marconi. In 1894 Marconi experimentally transmitted Hertzian waves around his own house and estate. In 1895 he tied a telegraph machine into a circuit and found he could send Morse code signals through the air: he had invented wireless telegraphy. Unable to interest the Italian government in his invention, he moved to England and established the Marconi Wireless Telegraph Company (1897-1900). Aided by the English physicist Oliver Lodge, Marconi learned how to transmit waves of definite length and devised receivers that could be tuned to receive waves of specific length—the origins of radio, although neither man recognized it at the time. Marconi built a transmitter in Cornwall and a receiving antenna first on Cape Cod then in Newfoundland, where, on 12 December 1901 he received the first transatlantic wireless message, in Morse code, an event that made him famous.
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Science and the New Foundations
A New Kind of Patronage.
Modern American science, especially that carried out in major universities and hospitals, has been highly dependent not only on government support but on the aid of large philanthropic organizations known as foundations. Until the first decade of the twentieth century, however, American scientists either worked in universities or in some cases government bureaus, both of which supported research on a modest level. If they conceived of projects that were out of the ordinary, scientists either had to find a private donor or put up the money themselves. In 1902 the Carnegie Institution was founded by Andrew Carnegie; then in 1909 John D. Rockefeller established the Rockefeller Foundation. Both organizations believed that promising scientific ideas and capable scientists ought to be supported substantially, but there were no precedents to guide either the new foundations or the scientists themselves in spending the relatively vast sums now available to them.
The Carnegie Institution.
Andrew Carnegie, a steel magnate and follower of Herbert Spencer's doctrine of progress as an immutable law of nature, caused a sensation in late 1901 when he announced that he intended to donate $10 million to promote scientific research. He was disturbed by the undistinguished place held by the United States in the ranks of world...
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The concept of the submarine is an old one and appears always to have been linked to military uses. As long ago as the fifteenth century the Italian engineer Roberto Valturio designed (but probably never built) a sub-marine powered by paddle wheels. In the seventeenth century the Dutch engineer Cornelius Drebbel built a diving bell that was open at the bottom and held several passengers. Both the English natural philosopher John Wilkins and the Frenchman Marin Mersenne speculated on whether a ship might be made to navigate underwater. In the eighteenth century David Bushneil of Connecticut built a submarine named the Turtle that was used during the Revolutionary War to attack a British ship in New York harbor in August 1776. Jules Verne, of course, popularized the concept in his famous novel Twenty Thousand Leagues Under the Sea (1873).
The First Holland Models.
John P. Holland made his first design for a submarine in 1873, shortly after arriving in Boston from his native Ireland. His earliest design was a one-man boat, fifteen feet long, which was operated with pedals and equipped with air reservoirs divided by oiled silk panels. His first model with a metal hull, Holland's Boat No. 1, was probably the smallest submarine ever built, only fourteen and a half feet long. The pedals were replaced by a gasoline...
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Burbank, Luther 1849-1926
Luther Burbank was an American original: largelyself-taught, he was an inventor and tinkerer by temperament but worked in the organic, rather than the mechanical, world and had an immense influence on academic botany and genetics. Born in Lancaster, Massachusetts, Burbank's first job was with the Ames Plow Company in Worcester (1864-1867). Then he attended the Lancaster Academy for a year, during which he first read Charles Darwin's On The Variation of Animals and Plants Under Domestication (1868), a book that exercised a profound influence on his career. Burbank learned from Darwin the methods of artificial selection that breeders use to develop desirable characteristics in domestic plants and animals. On his family's farm in Lunenburg, Massachusetts, he developed the Burbank potato, an immensely popular and economically important variety, the antecedent of the Idaho potato. In 1875 he moved to California where he...
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De Forest, Lee 1873-1961
Childhood and Education.
Born in Council Bluffs, Iowa, Lee De Forest was raised in Alabama, where his father was president of Talladega College. He studied engineering at Yale University's Sheffield Scientific School and then continued as a graduate student in physics. His favorite teacher was J. Williard Gibbs, but Gibbs was a theoretician who could not instruct in practical matters. While in graduate school De Forest read Nikola Tesla's lectures on high-voltage, high-frequency electric current phenomena, because he intended to ask Tesla for a job. Tesla's laboratory in New York, De Forest later explained, "was a fabulous domain into which all ambitious young electric students aspired to enter and there remain." In 1896 he met Tesla at his laboratory. De Forest's principal interest was radiotelegraphy, and his 1899 doctoral thesis on "Reflection of Hertzian Waves from the Ends of Parallel Wires" was a means for advancing his understanding of the phenomena involved.
In 1901 De Forest devised a telegraph transmitter that replaced the clumsy spark coil and supplied a steady, high-frequency spark. "From the start I had the aim in view," he later admitted, "to make my name at least rank with that of Marconi." He then launched the De Forest Wireless Telegraph company. He wanted...
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Edison, Thomas Alva 1847-1931
Life and Legend.
The story of Thomas Edison's youth was retold many times around the beginning of the twentieth century and was embroidered with anecdotes that lent a Horatio Alger quality to his biography. His background and many inventions made Edison the best-known scientific figure of the 1900s, a figure of near mythic proportions in a decade fascinated with new technologies. Edison worked as a youth on a train where he set up a chemistry laboratory and printing press on which he published a weekly paper for travelers. He was said to have been taught telegraphy as a reward for saving the life of a telegraph operator's son (the story was only partly true). After working for more than a decade as a telegraph boy, he launched his career as an inventor at the age of twenty-eight with a series of innovations that transformed telegraphy: first the duplex telegraph, which could transmit two messages simultaneously, one in each direction, and then the multiplex, which transmitted four messages, two in each direction. He sold the multiplex to Western Union in 1876 and...
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Hale, George Ellery 1868-1938
Born in Chicago, George Ellery Hale developed an early interest in astronomy. While still in high school he was fascinated with solar spectroscopy, a method of determining the chemical components of the Sun through the observation of its light. He was a physics major at Massachusetts Institute of Technology but spent his spare time at the Harvard Observatory working as an unpaid assistant. Among the many phenomena that interested him were solar prominences, clouds of gas above the surface of the Sun, which up to that time had only been observed and photographed during eclipses. At the age of twenty-one he devised an instrument, which he called the spectroheliograph, to photograph them in the light of day.
In 1892 Hale became associate professor of astrophysics at the University of Chicago. Until the late nineteenth century, astronomers had been mainly interested in observing the motion of celestial bodies. Those few who were interested in their physical nature were astrophysicists. For Hale and others the main method of research was spectrography, a field that required a physics laboratory in which to make spectrographic analyses under controlled conditions to compare with observational results. Astrophysics also required larger reflecting telescopes than were currently in...
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Hall, G. Stanley 1844-1924
G. Stanley Hall was one of the first American "scientific" psychologists. Along with William James and others he established psychology as an academic discipline in the United States. After receiving his education from Williams College and the Union Theological Seminary, he became a philosophy instructor at Antioch College, where in 1872 he read Wilhelm Wundt's book on physiological psychology and decided to redirect his efforts. Psychology had been considered a branch of philosophy until Wundt began to study the physiology of the nervous system, the localization of functions in the brain, and the physiology of sense perception. Hall returned to graduate school and received his doctorate under James at Harvard in 1878.
At Harvard, Hall performed experiments in the line of Wundt's famous research on reaction time. He was especially interested in the way perceptions were registered by muscles and also studied...
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Michelson, Albert Abraham 1852-1931
PHYSICIST AND FIRST AMERICAN NOBEL PRIZE WINNER
Albert Abraham Michelson was born in Prussia, in 1852, immigrating with his family at the age of four first to Panama and then to San Francisco, where his father became an itinerant merchant serving the mining camps of the Gold Rush days. He was sent to boarding school where he developed an interest in science and, after an interview in 1869 with President Ulysses Grant, was appointed to the Naval Academy at Annapolis. Upon graduation he was named physics instructor at the academy. He became interested in the speed of light and how to measure it accurately. As a result he was granted a leave of absence, which permitted him to spend 1880 to 1882 in Europe, much of the time in the physics laboratory of Hermann von Helmholtz in Berlin.
The Velocity of Light.
The problem of measuring the speed of light had both practical and theoretical aspects. Under the then-current theory, space was filled with an invisible substance known as the ether, through which light waves were thought to be propagated. Michelson's working hypothesis was that inasmuch as the ether is at rest and the earth moves through it, the speed of light on the earth's surface should be affected by the density and flow of the ether. In Helmholtz's laboratory (and with the financial assistance of...
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Peary, Robert Edwin 1856-1920
ADMIRAL AND ARCTIC EXPLORER
Born in Cresson, Pennsylvania, Robert Edwin Peary studied civil engineering at Bowdoin College in Maine, graduating in 1876. In 1879 he joined the U.S. Coast and Geodetic service as a draftsman, and he signed up with the navy as a civil engineer in 1881. In 1884 and 1885 he was sent with a navy expedition to survey prospects for an interoceanic canal in Nicaragua, where he devised locks of a great height for the proposed channel. He returned to Nicaragua in 1887 in charge of new canal surveys. When Congress finally opted for a Panama site in 1902, Peary's surveys were forgotten.
Peary's first northern expeditions were to Greenland. In 1886 he set out to cross the island from the western coast on a one-man sled of his own design, achieving greater penetration of the inland ice cap than ever before and greater elevation (2,125 feet). The area he explored around Mount Wistar has ever since been called Peary Land. He realized that a party equipped with snowshoes and skis could use the ice cap as an "imperial highway" to reach the eastern coast. On a second expedition in 1892 he crossed the island northeastward from Whale Sound. This sled trip made him a world figure. Another land crossing in 1895 confirmed that Greenland was an island. On summer trips in 1896 and 1897...
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Steinmetz, Charles Proteus 1865-1923
Early Life in Europe.
Charles Proteus Steinmetz was born in Breslau, Germany (now Wroclaw, Poland), in 1865. He was educated at the University of Breslau, whose physics department had a solid reputation in electrophysics, and was a doctoral candidate in mathematics. Felix Auerbach, his professor of mathematical physics, encouraged all of his students to develop mathematical theories of how specific pieces of electrical equipment work. Steinmetz was forced to leave Breslau because of his socialist politics and went to Zurich, Switzerland, where he enrolled for a semester of engineering at the Polytechnic Institute. While there he published his first two articles on electrical engineering: one on the resistance of conductors, the other a mathematical theory of the transformer. When the Breslau police issued a warrant for his arrest in 1889, he decided to immigrate to the United States.
First Years in America.
In the 1890s American electrical engineering was entering its golden age: the electric illuminating and power industries were in their infancy, as was the telephone. The radio would soon be developed. Steinmetz's training in mathematics and his interest in mathematical physics were virtually unrivaled in the American electric world and assured him a rapid rise in the industry. He was hired...
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Wright, Wilbur 1867-1912 and Wright, Orville 1871-1948
The Bicycle Shop.
Wilbur Wright was born on a farm in Indiana in 1867. His brother, Orville, was born in 1871, after the Wright family had moved to Dayton, Ohio. Their father was a bishop of the United Brethren in Christ and edited and published several church papers. The Wright brothers' first enterprise was a print shop, which they ran from 1889 until 1892, when they joined in the national obsession for bike riding and bought a bicycle shop. In 1895 they began to manufacture bicycles. The Wrights became interested in aeronautics in 1899 and immersed themselves in the available literature. From their analysis of a long line of failed attempts with heavier-than-air machines they concluded that the first step would be to master the principles of flight by observation and then by using gliders. Only then, they believed, could one think about combining an engine with the wing structure.
Between 1899 and 1903 the brothers achieved a series of conceptual and technical breakthroughs that made flight possible. The first was the recognition in 1900 of the desirability of...
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People in the News
General Electric engineer Ernst Alexanderson designed a ten-thousand-cycle alternator for the first successful radio transmission at Brant Rock, Massachusetts, in 1905.
Wilbur O. Atwater of the U.S. Department of Agriculture invented the respiratory calorimeter in 1904.
In 1909 Belgian-born chemist Leo Hendrik Baekeland announced the development of Bakelite, a condensed resin that became a standard insulation product.
Edward Binney, a Pennsylvania chemist, developed the Crayola crayon in 1902.
In 1903 Percy Brown established a radiology department, using new X-ray technology, at Children's Hospital in Boston.
Thaddeus Cahill exhibited his electric typewriter at the Pan-American Exhibition in Buffalo in 1901.
In 1906 Willis H. Carrier invented air conditioning.
In 1908 Frederick G. Cottrell patented the electrolytic precipitator, an air purifying device that removes particulate materials from factory smokestacks.
In 1901 Reginald Fessenden, an engineering professor at the University of Pittsburgh, invented a high-frequency alternating current generator.
Yale physics professor Josiah Willard Gibbs published Elementary Principles in...
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Timothy Field Allen, 65, botanist, studied mainly Characeae, a group of algae, 5 December 1902.
Philip Danforth Armour, 69, meatpacking pioneer who adopted assembly-line methods for processing meat, 6 January 1901.
Wilbur Olin Atwater, 63, director of the first agricultural experiment station at Middletown, Connecticut, from 1875 to 1877, inventor (with E. B. Rosa) of the Atwater-Rosa calorimeter, 22 September 1907.
Hans Herman Behr, 86, entomologist and botanist, studied butterflies of California, 6 March 1904.
Alexander Melville Bell, 86, father of Alexander Graham Bell and founder of the scientific study of speech who devised a physiological alphabet that visually represented the sounds of the human voice, 7 August 1905.
Lorin Blodget, 78, climatologist, conducted early research on atmospheric physics, 24 March 1901.
Henry Carrington Bolton, 60, chemist, researched compounds of uranium, 19 November 1903.
DeWitt Bristol Brace, 42, physicist who studied the factors affecting the velocity of light propagated through matter, 2 October 1905.
William Keith Brooks, 60, invertebrate marine zoologist,12 November 1908.
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Aero Club of America, Navigating the Air: A Scientific Statement of the Progress of Aeronautical Science up to the Present Time (New York: Doubleday, Page, 1907);
Alphonse Berget, The Conquest of the Air: Aeronautics, Aviation, History, Theory, Practice (New York: Putnam, 1909);
Arthur Bird, Looking Forward: The Phenomenal Progress of Electricity in 1912 (Northampton, Mass.: Valley View, 1906);
H. A. Bumstead and R. G. Van Name, eds., The Scientific Papers of J. Williard Gibbs, 2 volumes (New York: Longmans, Green 1906);
Luther Burbank, The Training of the Human Plant (New York: Century, 1907);
A. Frederick Collins, Wireless Telegraphy: Its History, Theory and Practice (New York: McGraw, 1905);
C. Field, The Story of the Submarine (Philadelphia: Lippincott, 1907);
Josiah Williard Gibbs, Elementary Principles in Statistical Mechanics (New York: Scribners, 1902);
Grove Karl Gilbert and others, John Wesley Powell, A Memorial (Chicago: Open Court, 1904);
Augustus Gottinger, The Flora of Tennessee and a Philosophy of Botany (Nashville, 1901);
George Ellery Hale, The Study of Stellar Evolution (Chicago: University of...
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Important Events in Science and Technology, 1900–1909
- Marie Curie discovers that an atom can spontaneously break apart, releasing energy. Scientists call this phenomenon "radioactivity."
- Sigmund Freud publishes On the Interpretation of Dreams in German.
- In April, Thomas Alva Edison invents the nickel-alkaline storage battery.
- On May 14, Dutch botanist Hugo de Vries announces his discovery of Austrian monk Gregor Mendel's three laws of genetics. Later in 1900, two other scientists, Carl Correns and Erich Tschermak, claim the same discovery.
- In July, geologists at the University of Berlin in Germany invent the modern pendulum seismograph for the detection of earthquakes. U.S. universities, led by the University of California, Berkeley, build seismographs in their geology departments.
- On July 2, the first zeppelin dirigible flies in Germany.
- In October, the U.S. Army builds its first dirigible. The army will use dirigibles for reconnaissance.
- On November 15, steel magnate Andrew Carnegie founds the Carnegie Institute of Technology in Pittsburgh, Pennsylvania. It will become Carnegie-Mellon University, a center for education and research in engineering and science.
- On December 14, German physicist Max Planck announces the basis of quantum theory: energy is...
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