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Men and Women of Science

ca. 400 B.C.

Hippocrates establishes the fundamental principles of medical science.

Democritus proposes the first known atomic theory of matter.

ca. 345 B.C.

Aristotle develops theories about the nature of matter; he provides proofs of the earth’s spherical shape.

ca. 240 B.C.

Archimedes establishes fundamental principles of experimental science.

ca. 135 B.C.

Hipparchus discovers the precession of the equinoxes; he develops a system of star classification by magnitude.

ca. 7 B.C.

Strabo, a Greek geographer and historian, completes the 17-volume Geography, which noted that the rising and sinking of lands was due, partially, to volcanoes and earthquakes.

ca. A.D. 70

Pliny the Elder, a Roman scholar, writes the 37-volume Historia Naturalis that recorded all Roman knowledge of rocks, minerals, and fossils. Pliny dies in A.D. 79 observing the eruption of Vesuvius that destroyed the city of Pompeii.

ca. A.D. 150.

Ptolemy formulates the classical system of astronomy, which was accepted in the West for over 1,500 years.

ca. A.D 175

Galen discovers certain principles of the circulation of blood in animals and humans.

ca. A.D. 900

Rhazes a Persian-born physician, describes measles and smallpox.

ca. A.D. 1000

Avicenna, an Arab physician, produces a medical encyclopedia that accurately describes meningitis, tetanus, and many other diseases.

ca. 1247

Roger Bacon establishes certain principles of the modern, empirical, scientific method.

ca. 1514

Nicolaus Copernicus formulates the theory that the earth revolves around the sun; this overthrows the 1,500-year-old Ptolematic system.

ca. 1540

Phillippus Aureolus Paracelsus pioneers the application of chemistry to medicine.

1543

Andreas Vesalius publishes a treatise containing the first accurate anatomical portrayal of the human body.

ca. 1550

Ambroise Pare introduces surgical techniques that anticipate modern surgery, earning him the title “father of modern surgery.”

1556

Georgius Agricola, aphysician from Saxony, writes De Re Metallica, which becomes the basis for modern studies and books on metallurgy and mining.

1572

Tycho Brahe sights a supernova, or exploding star, which disproves the ancient idea that the heavens cannot change.

ca. 1600

William Gilbert provides a foundation for the study of electricity and magnetism.

1610

Galileo improves the telescope and observes the heavens; he helps found modern scientific method.

ca. 1618

Johannes Kepler formulates the laws of planetary motion.

1620

Francis Bacon publishes The New Atlantis, which describes a modern research institution. This and earlier works by Bacon contributes to the modern scientific method.

1628

William Harvey publishes a landmark treatise on the human heart and the circulation of blood.

1642

Blaise Pascal invents the first calculating machine, which is the direct ancestor of modern calculators and cash registers.

ca. 1637-1644

Rene Descartes introduces the modern philosophy of rationalism, which contributes to the human will for knowledge and to the modern scientific method.

1651

William Harvey publishes a treatise that establishes the foundation of the science of embryology.

ca. 1655

William Boyle and Robert Hooke build air pumps with which they investigate vacuums.

1660

The Royal Society, an organization to promote the natural sciences, is founded in London.

1661

Robert Boyle publishes a book that descibes his theory of matter.

Marcello Malpighi describes capillaries viewed through a microscope.

1665

Robert Hooke observes and describes cells in cork.

ca. 1665-1666

Isaac Newton conducts his first investigation on gravity and motion.

1666

The Academy of Sciences is founded in Paris.

1669

Nicolaus Steno, a Danish physician, formulated the iaw of superposition—that is, layers of rock are always deposited with the oldest strata on the bottom and the youngest on the top.

Jan Swammerdam publishes a treatise on metamorphosisi of insects.

ca. 1678

Christian Huygens formulates the wave theory of light

1704

Isaac Newton publishes his discoveries in optics.

1705

Edmond Halley publishes Synopsis of the Astronomy of Comets, in which he describes and accurately predicts the reappearance of the comet that will come to bear his name.

1730

Daniel Bernoulli develops the kinetic theory of gases.

1751-1772

Diderot and d’Alembert publish a 28-volume encyclopedia, in which they catalog the science and technology of their day.

ca. 1752

Joseph Black identifies carbon dioxide.

1753

Carolus Linnaeus publishes a fundamental treatise on plant classification.

1755

Immanuel Kant, a German philosopher, suggests that the sun and planets were formed from the same elements and in the same way.

1758

Carolus Linnaeus publishes his treatise on animal classification.

1766

Henry Cavendish discovers properties of hydrogen.

1770

David Rittenhouse builds a precise model of the solar system.

1774

Joseph Priestly and Carl Scheele independently discover oxygen.

1777

Antoine Lavoisier gives the first accurate scientific explanation of combustion (fire).

1781

Sir William Herschel discovers the planet Uranus.

1784-1785

Henry Cavendish discovers that water is a chemical compound composed of hydrogen and oxygen.

1785

Charles Coulomb formulates the laws of attraction and repulsion between electrically charged particles.

1789

Antoine Lavoisier publishes the first modern textbook on chemistry.

ca. 1791-1796

Benjamin Banneker, an American astronomer and mathematician, publishes a series of almanacs that include his own astronomical and tidal calculations.

ca. 1792-1795

Count Alessandro Volta builds the first electric battery—the voltaic pile.

1796

Edward Jenner gives the first successful vaccination —for smallpox.

Pierre Simon de Laplace a French mathematician, proposes that the sun and planets are formed from a spinning cloud of gas called a nebula.

ca. 1800-1805

Baron Cuvier develops a system of classifying animals according to body types; he establishes the science of comparative anatomy.

1803

John Dalton develops an atomic theory of chemical elements.

1807

Humphry Davy isolates the elements sodium and potassium.

1811

Amadeo Avogadro formulates the theory that equal volumes of all gases at the same temperature and pressure contain equal numbers of particles.

1818

Jons Jacob Berzelius published his study of atomic weights of elements, using oxygen as a standard against which others are measured.

1820

Hans Oersted discovers the magnetic field surronding a conductor carrying an electric current.

ca. 1822

Andre Ampere discovers the basic laws of electromagnetism.

1822-1834

Charles Babbage designs his first computer. His models were in many ways equal to the first computers of the electronic age.

1826

Joseph Niepce produces the first photograph.

1827

Robert Brown described the agitation of microscopic particles, now known as Brownian motion.

1828

Caroline Herschel is awarded a gold medal from the Royal Astronomical Society for her catalog of nebulae.

Friedrich Wohler synthesizes the organic substance urea from inorganic materials.

1831

Robert Brown discovers the nucleus in living cells.

Michael Faraday and Joseph Henry independently discover the principle of electromagnetic induction.

1830-1833

Charles Lyell publishes Principles of Geology, founding the modern science of geology.

1835

Joseph Henry publishes his discoveries on self-induction.

ca. 1838

Matthias Schleiden and Theodor Schwann propose that the cell is a basic structural and functional unit of all living things.

ca. 1840

Louis Agassiz theorizes that huge sheets of ice once extended from the North Pole to Central Europe, dramatically changing the earth’s surface.

ca. 1845

Crawford Long and William T. G. Morton discover that ether gas could safely be used to put patients to sleep during surgery.

1846

Johann Galle and Heinrich L. d’Arrest discover the planet Neptune.

1847

Maria Mitchell, one of the first important astronomers in the U.S., discovers a new comet.

1849

Elizabeth Blackwell is the first women to receive a medical degree in the U.S.

1850

Hermann Helmholtz measures the speed of a human nerve impulse, proving that living matter could be analyzed in the same way as nonliving matter.

ca. 1850

James P. Joule discovers that energy and heat are interchangeable at a fixed rate.

1851

Lord Kelvin publishes “On the Dynamical Theory of Heat,” which contains the second law of thermodynamics.

ca. 1855

Robert Bunsen and Gustaz Kirchhoff discover that atoms of each chemical element produce a certain set of spectral lines; this leads to the identification of the elements that make up a star.

1856

Sir William Perkin creates the first synthetic dye.

1858

Rudolf Virchow publishes Cellular Pathology, establishing the idea that diseases should be studied at the cellular level.

ca. 1863-1864

Louis Pasteur develops the process known as pasteurization.

1864

James Clerk Maxwell predicts the existence of electromagnetic waves.

1865

Joseph Lister pioneers antiseptic surgery.

Friedrich Kekule von Stradonitz describes the molecular structure of benzene, laying the foundations for modern organic chemistry.

1866

Gregor Mendel publishes his pioneering work in heredity.

1869

Dmitri Mendeleev proposes a form of the periodic table of elements.

1875-1878

Josiah Gibbs develops and publishes the phase rule, explaining the relationships between gases, solids, and liquids.

1876

Robert Koch proves that bacteria cause anthrax, thereby proving the germ theory.

1882

Robert Koch identifies the type of bacteria that causes tuberculosis.

1885

Louis Pasteur administers the first successful rabies vaccine.

1886-1887

Heinrich Hertz discovers electromagnetic waves.

1887

Albert Michelson and Edward Morley devise an experiment that disproves the existence of ether.

1890

John Muir’s arguments for conservation helped pass the Yosemite National Park bill, creating Yosemite National Park and Sequoia National Park.

1893

Daniel Hale Williams performs the first open-heart surgery.

ca. 1894

Shibasaburo Kitasato discovers the bacillus that causes bubonic plague.

1895

Wilhelm Roentgen discovers X rays.

Guglielmo Marconi transmits the first telegraphic signal through air.

1896

Antoine Henri Becquerel discovers natural radioactivity.

1897

Sir Joseph John Thomson discovers the electron.

1898

Pierre and Marie Curie isolate the radioactive element radium.

Gifford Pinchot is appointed chief of the U.S. Division of Forestry.

1900

Max Planck originates the quantum theory.

Sigmund Freud publishes the Interpretation of Dreams, a landmark treatise on psychotherapy.

1900-1903

Hugo de Vries publishes his mutation theory of evolution.

1902

Wilheim Wien discovers the atomic proton.

ca. 1903

Christiaan Eijkman and Frederick Hopkins demonstrate the existence of vitamins.

1904

Sir William Ramsay receives the Nobei Prize in chemistry for isolating argon, helium, neon, krypton, and xenon.

1905

Albert Einstein proposes the theory of relativity and a theory explaining the photoelectric effect.

Ernest Rutherford theorizes that the half-life of radioactive minerals could be used to determine the age of minerals.

ca. 1905

Elie Metchnikoff discovers the function of phagocytes in blood.

1906

Ernest Rutherford confirms the existence of the proton in the atomic nucleus.

1907

A.A. Michelson is the first American to win a Nobel prize in science.

1910

Thomas Hunt Morgan and his associates identify the gene as the basic unit of heredity and the chromosome as the cellular structure on which genes reside.

Marie Curie publishes a fundamental treatise on radioactivity.

1911

Marie Curie receives the Nobel Prize in chemistry for her work in isolating radium.

1911

Ernest Rutherford formulates the modern nuclear theory of the atom.
Heike Onnes discovers superconductivity.

1912

Henrietta Swan Leavitt publishes a table of her findings on the period lengths of variable stars.

Garrett Augustus Morgan designs a gas mask, winning first prize at the second International Exposition of Safety and Sanitation in 1914.

1913

Robert Millikan measures the charge of the electron.

1914

Niels Bohr publishes his theory of atomic structure.

1915

Ernest Everett Just receives the Spingarn Medal for his study of fertilization in marine invertebrates and the role of the cell surface in the development of such organisms.

ca. 1916

George Washington Carver develops an enormous variety of industrial uses for American agricultural crops.

1916

Gilbert Lewis descibes electron bonding between atoms.

Albert Einstein publishes his general theory of relativity.

1919

Ernest Rutherford produces the first artificial disintegration of an atom.

1921

John James Macleod and Sir Frederick Banting discover insulin.

Margaret Sanger is founder of the Birth Control League, later renamed Planned Parenthood Federation of America.

1924

Louis De Broglie proposes the wave theory of the electron.

1925-1926

Erwin Schrodinger develops the principles of wave mechanics.

Lloyd A. Hail serves as technical director and chief chemist at Griffiths Laboratories in Chicago.

1926

Thomas Hunt Morgan publishes The Theory of the Gene, a landmark study of genetics.

1927

Hermann Joseph Muller publishes his discovery that X rays can cause genetic mutation.

Charles Elton, an English biologist, publishes Animal Ecology and Evolution, a landmark study of the balance of nature.

1928

Sir Alexander Fleming discovers penicillin.

Margaret Mead publishes her first book, Coming of Age in Samoa.

1929

Edwin Hubble demonstrates that the universe is expanding.

Louis Victor De Broglie receives the Nobel Prize for physics.

1931

Karl Jansky detects radio waves outside the solar system.

1932

Sir James Chadwick discovers the atomic neutron.

1934

Enrico Fermi splits the atom.

Roger Tory Peterson publishes his first manual, Field Guide to the Birds.

1935

Percy Lavon Julian creates synthetic phytosostigmine, a drug used to treat glaucoma.

1938-1939

Otto Hahn and Fritz Strassman split the uranium atom, and Lise Meitner and Otto Frisch

develop a mathematical theory to explain the split.

1939

Ernest O. Lawrence receives the Nobel prize in physics for his invention of the cyclotron.

Helen Sawyer Hogg publishes her Catalogue of Variable Stars in Globular Clusters.

1940

Karl Landsteiner and A.S. Weiner discover the Rh factor in human blood.

Glenn T. Seaborg discovers plutonium.

1941

Helen Brooke Taussig and Alfred Blalock team up to develop an operation to help blue babies.

1942

Enrico Fermi produces the first controlled nuclear chain reaction.

1943

Selman Waksman discovers streptomycin.

1943-1945

Lloyd Quarterman works with Fermi’s team to create the first nuclear reactor.

1944

Oswald Avery demonstrates that genes consist of DNA.

Alfred Blalock performs the first blue baby operation.

1945

Alan Mathison Turing helps build the first British electronic digital computer.

ca. 1946

Melvin Calvin traces the chain of chemical reactions involved in photosynthesis.

1947

John Bardeen, Walter Brattain, and William Shockley invent the transisitor.

Gerty T. Cori and her husband Carl F. Cori win the Nobel prize for physiology or medicine.

1950s

Grace Murray Hopper develops COBOL, one of the most widely used computer programming languages.

Jane Cooke Wright begins studying the effects of various chemotherapies on cancerous growths.

1952

Edward Teller develops the first hydrogen bomb.

ca.1952-1953

Rosalind Elsie Franklin discovers the helical structure of DNA.

Jonas Salk announces the development of the first trial polio vaccine.

Francis Crick, with James Watson, creates a three-dimensional model of the DNA molecule

1954

Linus Pauling is the first sole recepient of the Nobel prize for chemistry.

1955

Owen Chamberlain and Emilio Segre discover the antiproton.

1957

The Soviet Union launches Sputnik I, the first artificial satellite.

Roger Revelle is among the first to study the problems of global warming and the greenhouse effect

1959

Roslyn Yalow develops radioimmunassay

1960s

Jane Goodall begins studying chimpanzees.

1960

Theodore H. Maiman builds the first laser.

1961

Yuri Gagarin, a Russian cosmonaut, becomes the first human to orbit the earth in a spaceship.

1962

Rachel Carson publishes Silent Spring, awakening America to the problems of pollution.

1965

Dorothy Crowfoot Hodgkin wins the Nobel Prize for determining the structure of the vitamin B12 molecule.

Radio astronomers discover primordial, background radiation in the universe believed to originate in the “big bang.”

1969

The United States makes the first manned landing on the moon.

1972

John Bardeen, Leon Cooper, and John Robert Schrieffer receive a Nobel Prize in physics for developing the theory of superconductivity.

1974

Burton Richter and Samuel C.C. Ting discover the psi particle.

1975

Andrei Sakharov is the first citizen of the U.S.S.R. to be awarded the Nobel Peace Prize.

1978

Scientists use genetically engineered bacteria to produce human insulin.

1979

Walter Eugene Massey is director of the University of Chicago’s Argonne National Laboratory.

Steven Weinberg is awarded the Nobei prize for physics.

ca. 1980

Geneticists produce recombinant DNA in bacteria.

ca. 1981

Chemists begin work on the development of a solar-powered device that produces hydrogen fuel by means of the chemical breakdown of water.

1983

Carlo Rubbia and his research team discover the W particle and Z particle.

Dian Fossey publishes Gorillas in the Mist

Scientists use genetic engineering to transfer human growth genes into mice, triggering twice-normal growth in the mice.

Barbara McClintock wins the Nobel Prize for physiology or medicine for her discovery that certain genes can change their position in the chromosomes of cells.

1987

Benjamin Carson successfully separates conjoined twins.

1988

Stephen William Hawking publishes A Brief History of Time.

Leon Lederman wins the Nobel prize in physics.

1993

Mae Jemison is the first African-American woman to travel in space.