By: Albert A. Michelson
Source: Michelson, Albert A. The Velocity of Light. Vol. 9 of The Decennial Publications. Chicago: University of Chicago Press, 1902, 7–9.
About the Author: Albert Abraham Michelson (1852–1931) was born in what is today Germany. He immigrated with his family to Panama, then to San Francisco. In 1873 he graduated from the Naval Academy at Annapolis, Maryland, where he stayed to teach physics. In 1881 he resigned from the navy to accept a professorship at the Case Institute of Applied Science in Cleveland, Ohio. In 1907 he became the first American to win a Nobel Prize in physics.
In the seventeenth century Isaac Newton passed white light through a prism, refracting it into a spectrum of colors. Light, he reasoned, must consist of particles of different sizes, with each size corresponding to a color. Particles of a particular size create the sensation of a particular color when they strike the retina.
This view of light and color perception prevailed until the nineteenth century, when British mathematician, physicist, and linguist Thomas Young passed light through two slits onto a screen. As the light passed through the slits, it broadened...
(The entire section is 1528 words.)
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Elementary Principles in Statistical Mechanics
By: J. Willard Gibbs
Source: Gibbs, J. Willard. Elementary Principles in Statistical Mechanics. New York: Scribner's, 1902. Reprint, Wood-bridge, Conn.: Ox Bow Press, 1981, vi–viii.
About the Author: Josiah Willard Gibbs (1839–1903) was born in New Haven, Connecticut, and received a Ph.D. in engineering in 1863 from Yale University. After studying mathematics and physics in Europe, he became professor of mathematical physics at Yale in 1871. Thereafter he seldom left New Haven, living the rest of his life in the house where he had been born.
The seventeenth-century classical physics of Isaac Newton culminated in the nineteenth century in three grand theories that absorbed the attention of J. Willard Gibbs: thermodynamics, kinetic theory, and statistical mechanics. At mid-century scientists had formalized the first law of thermodynamics, which says that the total energy in a closed system (a system to which nothing is added or subtracted) remains constant, though energy may be converted from one form to another (as, for example, when an athlete transforms the chemical energy from food into the energy of motion and heat). Then in 1850 the German physicist Rudolf Clausius formalized the second law...
(The entire section is 1499 words.)
Diary Entry of December 17, 1903
By: Orville Wright
Date: December 17, 1903
Source: Wright, Orville. Diary entry of December 17, 1903. In McFarland, Marvin W., ed. The Papers of Wilbur and Orville Wright. Vol. 1: 1899–1905. New York: McGraw-Hill, 1953, 394–396.
About the Author: Wilbur Wright (1867–1912) was born on a farm in Indiana. The family moved to Dayton, Ohio, where his brother Orville was born in 1871. The two ran a print shop from 1889 to 1892 and began manufacturing bicycles in 1895. In 1899 they started tinkering with gliders, adding a gasoline engine in 1903 to achieve the first powered flight at Kitty Hawk, North Carolina. Wilbur died in 1912 and Orville in 1948.
Until the early twentieth century, flight was possible only with gliders, hot-air balloons, and dirigibles. Although Smithsonian Institution director Samuel P. Langley, an advocate of the steam engine, remarked in 1891 that "Mechanical flight is possible with engines we now possess," the steam engine and electric motor were too heavy for the horsepower they generated. Starting in 1887 Langley tinkered with model airplanes as heavy as thirty pounds, and in 1896 he actually flew a model with a twelve-foot wingspan, a one-horsepower steam engine, and twin propellers...
(The entire section is 1320 words.)
Experiments with Alternate Currents of High Potential and High Frequency
By: Nikola Tesla
Source: Tesla, Nikola. Experiments with Alternate Currents of High Potential and High Frequency. New York: McGraw-Hill, 1904, 3–4.
About the Author: Nikola Tesla (1856–1943) was born in Smiljan, Croatia, and immigrated to the United States in 1884. The next year he sold his patent rights to his alternating-current dynamos, transformers, and motors to George Westinghouse. In 1891 he invented the Tesla coil, an induction coil used in radio.
Chemical cells produced the first electric currents, but they were an expensive way of generating voltage, making long-distance electrical transmission out of the question. Physicists spent much of the nineteenth century trying to find an inexpensive alternative. In 1820 Dutch physicist Hans Christian Oersted deflected a compass needle by passing an electric current through a copper wire, proving that an electric current could produce a magnetic field. British physicist Michael Faraday realized that if an electric current could produce a magnetic field, then a magnetic field could in turn generate an electric current. In 1831 he induced an electric current by spinning a coil of wire between the north and south poles of a magnet....
(The entire section is 1261 words.)
Adolescence: Its Psychology
By: G. Stanley Hall
Source: Hall, G. Stanley. Adolescence: Its Psychology. New York: D. Appleton, 1905, ix, xiii, 2–3.
About the Author: Granville Stanley Hall (1844–1924) was born in Ashfield, Massachusetts, and received his Ph.D. in psychology from Harvard University in 1878. In 1884, he founded the first experimental psychology laboratory in the United States at Johns Hopkins University. In 1888, he became president of Clark University in Massachusetts and used his position to invite Sigmund Freud to lecture at the university in 1909.
In 1866 German naturalist Ernest Haeckel announced the theory of recapitulation, an interpretation of Charles Darwin's theory of evolution by natural selection. Darwin believed nature adapted species ever more closely to their environment, and it was this adaptation that evolved new species. Darwin was careful, though, not to suggest that evolution has a direction from lower to higher forms. Haeckel, in contrast, was the most prominent of several naturalists to impose direction on evolution. He ordered species from simplest to most complex, asserting that species always evolved toward greater complexity. His view that the most complex species were higher by...
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By: Henry Cullen Adams
Date: March 16, 1906
Source: U.S. Congress. Adams Act. 34 Stat. 63. March 16, 1906. In Knoblauch, Harold C., Ernest M. Law, and W. P. Meyer. State Agricultural Experiment Stations: A History of Research Policy and Procedure. Washington, D.C.: U.S. Government Printing Office, May 1962, 221–222.
About the Author: Henry Cullen Adams (1850–1906) was born in Verona, New York, but moved to Wisconsin, where he served in the Wisconsin State Assembly from 1883 to 1887. In 1902 he won election to the U.S. House of Representatives, where he served two terms and sponsored the law bearing his name that doubled federal appropriations to agricultural experiment stations.
The tension between applied science and pure research has been a long-standing one in American history. The goal of applied research is the discovery of useful knowledge—a cure for cancer, for example. The goal of pure research is knowledge for its own sake, without practical application. Throughout American history the proponents of applied science have held the upper hand. In the eighteenth century the prestige of Thomas Jefferson and Benjamin Franklin, the nation's most prominent scientists, set the scientific agenda. Both...
(The entire section is 1648 words.)
By: William James
Source: James, William. Pragmatism. New York: Longmans, Green, 1907. Reprinted in James, William. Pragmatism and Four Essays from The Meaning of Truth. New York: World, 1955, 79–80.
About the Author: William James (1842–1910) was born in New York City and received an M.D. from Harvard Medical School in 1869. A polymath interested in science, philosophy, psychology, and religion, he taught philosophy and psychology at Harvard University and was a founder of Pragmatism, a philosophical movement that influenced intellectuals at the turn of the century.
During the eighteenth and early nineteenth centuries natural history (what we now call biology) and theology were closely intertwined. Their relationship rested on the Design Argument: the premise that organisms are too intricate in their adaptation to the environment to have arisen by mechanistic forces. Bats, for example, navigate dark caves and track and capture insects by emitting high-frequency sounds whose echo they hear. Surely, the Design Argument runs, such precise adaptation cannot have arisen by happenstance. God must have designed bats and, by extension, all other species.
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Plant-Breeding: Being Six Lectures upon the Amelioration of Domestic Plants
By: Liberty Hyde Bailey
Source: Bailey, Liberty Hyde. Plant-Breeding: Being Six Lectures upon the Amelioration of Domestic Plants, 4th ed. New York: Macmillan, 1907, 155–157.
About the Author: Liberty Hyde Bailey (1858–1954) was born in South Haven, Michigan, and in 1884 became professor of horticulture at Michigan State University, where he established the first horticultural laboratory in the United States. In 1888, he joined the faculty at Cornell University, first as professor of botany and horticulture and later as dean of the College of Agriculture. He was the author of sixty-six books and seven hundred articles.
Throughout the nineteenth century theories of heredity fell into two camps. Scientists in the first camp, such as French naturalist Jean-Baptiste Lamarck, held that the environment affects heredity. In 1809, for example, Lamarck announced two laws of heredity. First, offspring inherit traits their parents acquired from the environment. For example, a giraffe that stretches its neck to reach leaves in a tree passes this additional length to its progeny. Second, organs grow with use and atrophy with disuse, and organisms pass these strengthened or weakened organs to their...
(The entire section is 1069 words.)
Comparative Physiology of the Brain and Comparative Psychology
By: Jacques Loeb
Source: Loeb, Jacques. Comparative Physiology of the Brain and Comparative Psychology. New York: G. P. Putnam's Sons, 1907, 10–11.
About the Author: Jacques Loeb (1859–1924) was born in Mayen, Prussia (now Germany), and received an M.D. from the University of Strasbourg in 1884. In 1891 he immigrated to the United States, where he held professorships at Bryn Mawr College in Pennsylvania, the University of Chicago, and the University of California, Berkeley. In 1910, he became a medical researcher at Rockefeller University in New York City.
Charles Darwin stimulated the development of psychology as a science by affirming that humans were part of the animal kingdom, not separate from it, making every aspect of human behavior appropriate for scientific, as opposed to theological, scrutiny. Yet from the beginning psychologists sought a compromise that elevated humans above other animals without claiming that they were the product of divine creation. This compromise was to single out humans as alone among animals in having a mind, which the brain generated of its own complexity. Mind differed from brain in lacking a material basis. Brain was an object, whereas mind was a...
(The entire section is 1028 words.)
Genetics and the Debate Over Acquired Traits
The Training of the Human Plant
By: Luther Burbank
Source: Burbank, Luther. The Training of the Human Plant. 1907. Reprint, New York: Century, 1916, 81–82.
About the Author: Luther Burbank (1849–1926) was born in Lancaster, Massachusetts, and was a self-taught plant breeder. In 1876, he established a fruit and vegetable farm in Santa Rosa, California, where he bred new varieties of fruits and vegetables. His work won praise from Dutch botanist Hugo de Vries and from Henry Ford and Thomas Edison, all of whom visited his farm.
"Darwin and Paleontology"
By: Henry Fairfield Osborn
Date: January 1, 1909
Source: Osborn, Henry Fairfield. "Darwin and Paleontology." In Fifty Years of Darwinism: Modern Aspects of Evolution. New York: Henry Holt, 1909, 235–237.
About the Author: Henry Fairfield Osborn (1857–1935) was born in Fairfield, Connecticut, and taught at Princeton University, first as an assistant professor of natural sciences and then as professor of comparative anatomy. In 1891, he joined the faculty at Columbia...
(The entire section is 1437 words.)
General Lectures on Electrical Engineering
By: Charles Steinmetz
Source: Steinmetz, Charles Proteus. General Lectures on Electrical Engineering, 3rd ed. Schenectady, N.Y.: Robson & Adee, 1908, 149–150.
About the Author: Charles Proteus Steinmetz (1865–1923) was born in Breslau, Germany (now Wroclaw, Poland). He studied mathematics as a doctoral candidate at the University of Breslau, but university officials expelled him for advocating socialism. To escape arrest for his radicalism, he immigrated to the United States, where he rose to chief engineer for General Electric. He was the author of twelve books and some 150 articles.
The harnessing of electricity as a source of power was an achievement of the nineteenth century. In 1831 British physicist Michael Faraday created a prototype of the dynamo (the electric generator), but not until 1880 did engineers and mathematicians perfect it, opening an era of inexpensive electricity. Electricity made possible the lightbulb and the telephone, but its effect on transportation was no less momentous. The dynamo also made possible the electric railway, which replaced the horse-drawn trolley in American cities along both coasts, around the Great Lakes, and in the South, which embraced the electric...
(The entire section is 1213 words.)
By: Charles B. Davenport
Date: January 1, 1909
Source: Davenport, Charles B. "Mutation." One of a series of centennial addresses in honor of Charles Darwin, given before the American Association for the Advancement of Science, Baltimore, January 1, 1909. Printed in Fifty Years of Darwinism: Modern Aspects of Evolution. New York: Henry Holt, 1909, 160–161.
About the Author: Charles Benedict Davenport (1866–1944) was born in Stamford, Connecticut, and received a Ph.D. in zoology from Harvard University in 1892. He taught there until 1899, when he became professor of zoology at the University of Chicago. From 1904 to 1934, he directed the department of genetics for the Station for Experimental Evolution at Cold Spring Harbor, New York, where he founded the Eugenics Record Office.
Life reproduces in two ways: cell division and sex. In contrast to cell division, sex produces organisms that differ from one another. Biologists have long debated whether these differences are continuous or discontinuous. In other words, are variations so slight that they form a continuum of gradual change, or are they large enough that they form a series of discrete traits? Human skin color is an example of continuous variation,...
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"The Cell in Relation to Heredity and Evolution"
By: Edmund B. Wilson
Date: January 1, 1909
Source: Wilson, Edmund B. "The Cell in Relation to Heredity and Evolution." One of a series of centennial addresses in honor of Charles Darwin, given before the American Association for the Advancement of Science, Baltimore, January 1, 1909. Printed in Fifty Years of Darwinism: Modern Aspects of Evolution. New York: Henry Holt, 1909, 98–100.
About the Author: Edmund Beecher Wilson (1856–1939) was born in Geneva, Illinois, and became a professor of zoology at Columbia University in 1891. He studied embryology, with a focus on cell biology, and became an advocate of the chromosome theory of inheritance. He established that sex chromosomes determine the sex of an organism.
At times, technology stimulates science. The microscope, for example, invented by Dutch spectacle makers around 1590, opened the field of cell biology, or cytology. This science developed gradually, though, and for more than half a century the microscope was more a curiosity than a research tool. In 1665, English physicist and naturalist Robert Hooke coined the term cell for the walled structures he saw in thin slices of magnified cork. Later in the century, others found cells in magnified...
(The entire section is 1304 words.)
The Evolution of Worlds
By: Percival Lowell
Source: Lowell, Percival. The Evolution of Worlds. New York: Macmillan, 1909, 1–3.
About the Author: Percival Lowell (1855–1916) was born in Boston. He published four novels on Asian culture before turning to astronomy. He built an observatory at Flagstaff, Arizona, through which he scanned Mars, popularizing the notion that intelligent life once inhabited it. Lowell predicted the existence of Pluto twenty-five years before its discovery.
The question of the origin and end of the universe fascinated the ancients, all of whom had creation myths, such as the Hebrew story of creation in Genesis, to account for its origin. For Christian scholars Christ's Parousia, or Second Coming, described the universe's end. Yet the twelfth-century Muslim philosopher Averroes warned that no evidence supported the claim that the universe had a beginning and one day would end. It was as logical to suppose the universe to be eternal as to suppose it bounded in time. The great sixteenth- and seventeenth-century Western astronomers—Nicolaus Copernicus, Galileo Galilei, Johannes Kepler, and Isaac Newton—described how the universe behaved, not how or when it had begun or would end....
(The entire section is 1246 words.)