Famous Scientists

638-548 B.C.	Thales of Miletus - Greek philosopher; developed theory of matter based upon water; recorded the attractive properties of rubbed amber and lodestone.
c.540-475 B.C.	Heraclitus - Greek philosopher; first of the Greeks to develop a theory of the human soul; he praised its creative resources and spoke of the importance of self-exploration; he spoke of the logos that is common to all and said that the universe is ruled by logos; he always urged that close attention be given to the polarites and concealed structures emodied in language.His famous claim that an idividual can and cannot step into the same river twice reveals an interest in criteria of unity and identity; even though all material constituents have undergone change, it is still, in a sence, the same river. Preoccupied with change, he declared that fire is the central element of the universe, and he postulated a world with no beginning and no end...
581-497 B.C.	Pythagoras - Greek philosopher and mathematician; held that numbers were basic to matter; the Pythagorean Theorem is named for his geometric formulation; developed atomic theory; students of his philosophy emphasized geometrical form as a basic property of atoms; developed mathematical relationships which led to musical harmony.
c.490-c.430 B.C.	Empedocles - Some suggest (c.484-c.424) - Greek doctor, poet and philosopher. To account for real change, he assumed that there must be more than one kind of matter, and he postulated four roots as elements; earth, air, fire, and water. Love and hate were considered principles of attraction and repulsion that alternately dominated the universe in a recurring cycle. Empedocles presented a kind of biological theory of natural selection in an imaginative poem, On Nature. He also played an importqant role in the development of the Western or Sicilian school of Greek medicine. He cured a plague at the Sicilian city of Selinus and claimed he was a god. One legend, which forms the basis of Matthew Arnold's poem Empedocles on Etna, held the Empedocles, tired of life and wanting people to believe that the gods had taken him with them, committed suicide by leaping into the crater of Mt. Etna.
470-399 B.C.	Socrates - Greek philosopher; emphasized the study of human nature in relationship to society; influence the growth of science through standards for clear definitions and classifications, for logic and order, and for prudent skepticism.
460-370 B.C.	Democritus of Abdera - Greek philosopher; pupil of Leucippus; developed atomic theory; elaborated idea that matter consisted of atoms having physical size and shape which constantly moved in a void and interacted in different ways; Greek word atoma means indivisible.
c.450 B.C.	Leucippus - proposed an atomic concept of matter.
428-347 B.C.	Plato - Greek philosopher; pupil of Socrates; dealt with the nature of the universe; developed atomic theory of chemical change; ascribed geometric forms composed of bounding planes to the elements of earth, fire, air and water based upon their physical properties; held that elements could convert into one another through rearrangement of bounding planes; used deductive reasoning as a learning method.
384-322 B.C.	Aristotle - updated engraving; Greek philosopher, educator and scientist; undertook a large-scale classification of plants and animals; introduced a method of scientific thinking that still plays a role today.
341-270 B.C.	Epicurus - Greek philosopher; founded the system known as Epicureanism. He studied with followers of Plato and Democritus before opening his school in Athens. The school, later called the Garden, accepted women and slaves. This, coupled with Epicurus' teachings concerning pleasure, led to public criticism of the school as a scene of debauchery. In reality, life there was fairly austere. Most of the writings of Epicurus have been lost. Fragments from his most important work, Peri physeos (On Nature), were recovered from the charred papyri of Herculaneum, buried by an eruption of Vesuvius in AD 79.
c.336-264 B.C.	Zeno of Cition - Greek philosopher; founded the Stoic school of philosophy which held that matter, space, etc. were continuous.
c.95-c.55 B.C.	Titus Lucretius Carus
69-30 B.C.	Cleopatra VII - experimented with poisons; influenced alchemists.
354-430	Aurelius Augustinus - (Saint Augustine) - North Africa; was the first to report that the forces exerted by rubbed amber and by lodstone are different properties.
c.760-c.815	Jabir ibn-Hayyan - "Geber"
c.850-c.925	Al-Razi - "Rhazes"
979-1037	Ibn-Sina - Avicenna - Islamic physician and philosopher; author of nearly 200 works in medicine, alchemy, language, philosophy and religion.
c.1397-c.1468	Johann Gutenberg - a craftsman from Mainz, Germany. Between 1430 and 1444 he was in Strasbourg, probably working as a goldsmith, and here he may have begun printing. In 1438 he entered a contract with three others to develop a refined printing technique and became the inventor of moveable-type mechanical printing in Europe. He printed the 42-line Gutenberg Bible (c.1455) but in the end he lost a suit from one of his creditors, who confiscated the type for the Bible. The suit left Gutenberg financially ruined. Aided by Konrad Humery, he was able to set up another press, but little is known of his work thereafter. The impact of printing was enormous - it led to an almost instant mass production of books and truly initiated the information age. The Reformation, the Renaissance, and the scientific period of the 17th century can hardly be contemplated without printed books.
1473-1543	Nicholas Copernicus - Polish astronomer; regarded the founder of modern astronomy. He was born in Torunac, Poland. He studied mathematics and optics at Cracow, then canon law at Bologna, before becoming canon of Frombork. Copernicus discovered the mathematically yet unproven heliocentric solar system. In his treatise, 'On the Revolutions of the Celestial Spheres' he postulated that the planets, including the earth, revolve around the sun, and that the earth revolved around its axis once every day. The work had a hostile reception when it was published (1543), as it challenged the ancient teaching of the Earth as the centre of the universe. In the 1600' Galileo and Kepler began to develop the physics that would prove Copernicus right.
1493-1541	Phillippus Aureolus Paracelsus (Theophrastus Bombast von Hohemheim) - Swiss physician; controversial figure in medicine and alchemy; promoted the production of chemical medicines for illnesses of the human body; saw the human body as a chemical system monitored by spiritual alchemists; developed many medical remedies; developed theoretical chemistry through sets of metal experiments which produced salt solutions; added salt to mercury and sulphur as components of metals.
1494-1555	Georg Bauer - "Agricola" - German educator, city official, and physician Georgius Agricola (Latinized for of George Bauer) is best known as the author of De re metallica (1556), a treatise on mining and metallurgy. The treatise was translated into English in 1912 by future U.S. president Herbert Hoover and his wife, Lou Henry Hoover. Agricola studied medicine at Leipzig University. He became a devoted follower of Erasmus, who wrote a foreward to Agricola's first book on mining and metallurgy (1930). While town physician of Joachimsthal (now Jachymov, Czech Republic), he became intensely interested in all aspects of the mining and metallurgy industry by which the town thrived and began a 25-year study of the subject, which culminated in hos posthumously published masterpiece. The 12-chapter treatise included 292 woodcult illustrations carfully executed by Blasius Weffring. Agricola also wrote a number of works on medicine, geology, mineralogy, politics, and economics.
1514-1564	Andreas Vesalius
1540-1603	William Gilbert - Some say (1544-1603) - English physician; known for his early studies on electricity and magnetism. His De magnete (1600) propounded the theory that the earth was a giant lodestone with north and south magnetic poles. His theory that the earth exerted a magnetic influence throughout the solar system was a precursor to the modern conception of gravity as an attracting force between masses. Gilbert was among the first to divide substances into electrics (spar, glass, amber) and nonelectrics.
c.1540-1616	Andreas Libau - "Libavius"
1561-1626	Francis Bacon - English philosopher and scientist; introduced the idea that an understanding of the natural world could be gained from direct observation and experimentation.
1564-1642	Galileo Galilei
1579-1644	Johann Baptista van Helmont - Flemish chemist; first to distinguish chemically produced gases; processes studied included combustion and fermentation; coined the term "gas".
1592-1655	Pierre Gassendi
1596-1650	Rene Descartes - French mathematician and philosopher; developed atomic theory through explanations of properties of matter.
1602-1686	Otto von Guericke
1604-1668	Johann Rudolf Glauber
1608-1647	Evangelista Torricelli - Italian physicist and mathematician; invented the barometer (1643).
1614-1672	Franz De le Boe (Latin name, Franciscus Sylvius; also, Francois Du Bois) - German physician, anatomist and chemist; based diagnoses and treatment of patients on blood acids, alkali and salts.
1620-1682	Jean Picard - French scientist; observed the luminous glow in the Torricellian vacuum of a barometer produced by motion of the mercury wen the untstrument was carried from place to place.
1623-1662	Blaise Pascal - French mathematician and scientist for whom the SI unit of pressure (Pascal) was named.
1627-1691	Robert Boyle - English physicist and chemist; experimented in pneumatics; through research, he rejected the accepted definition of matter; proposed Boyle's Law (1662).
?-1692	Hennig Brand
1630-1684	Edme Mariotte
1635-1682	Johann Joachim Becher
1642-1727	Issac Newton - English mathematician and scientist; developed theory of matter; first to demonstrate the color components of white light with a prism and the reconstruction of these colors into white light with a second prism; researched the optical characteristics of chemical substances; studied gravitation and motion; developed the law of gravitation.
1644-1710	Ole Christensen Roemer - Denmark; was the first to show that the velocity of light is finite. His conclusion was based on the variations of the time intervals between consecutive eclipses of one of the moons of Jupiter during the course of the revolution of the earth around the sun.
c.1650-1715	Thomas Savery
1656-1743	Edmund Halley - English astronomer; discovered the proper motion of stars and the periodicity of comets. His activities also ranged from the studying of archaeology to serving as deputy comptroller of the mint at Chester. He was a very important part of the English scientific community at the height of its activity. A graduate of Oxford, he became a member of the Royal Society at the age of twenty two. In 1676 to 1678 from the island of Saint Helena, he cataloged the positions of about 350 Southern Hemisphere stars and observed a transit of Mercury. He worked out a theory of cometary orbits and concluded that the comet of 1682, otherwise known as Halley's comet, was periodic and correctly predicted that it would return in 76 years. In 1710, he compared current star positions with those listed in Ptolemy's catalog, he determined that the stars must have a slight motion of their own.Halley was appointed Savilian professor of geometry at Oxford in 1704, and in 1720 he succeeded John Flamsteed as astronomer royal. At the Greenwich Observatory he used the first transit intrucment and devised a method for determining longitude at sea by means of lunar observations. Halley played an active role in the events and controversies of his time. He supported Isaac Newton morally and financially, pacified astronomer Johannes Hevelius regarding the disputed accuracy of methods for measuring stellar positions, and infuriated Flamsteed by scheming with Newton to publish Flamsteed's observations before they were complete. Among Halley's hardships were the murdering of his father, a prosperous salter and soapmaker, in 1684, and the death of his mother in 1672.
1660-1734	Georg Ernest Stahl
1663-1729	Thomas Newcomen - He is famous for inventing a steam engine in which steam admitted to a cylinder was condensed by cold water and the piston driven by atmospheric pressure. It was the first engine of it's time that would work on low-pressure steam. He worked on this with John Calley at first and then joined with Thomas Savery.Thomas Savery invented a steam engine also, but his ran on high-pressure steam which was very dangerous. Newcomen's engine was further improved near the end of the eighteenth century by a man named James Watt. Nevertheless Newcomen's invention was important because man no longer had to depend on horses or the wind or the non-consistent energy source of constantly running water. Instead man could count on the steam produced by simply boiling of water. The steam energy was the key factor in what became known as the Industrial Revolution. Newcomen's steam engine was especially useful in mines. It was used for transporting metals and other mining products. It did this very well and very efficiently. Savery and Newcomen combined their ideas to come up with the invention that started an entire new branch of discoveries; because of the steam engine, chemists now wondered about other chemicals and fire. Why some things would burn and others would not.
1668-1738	Hermann Boehaave
1677-1761	Stephen Hales
1694-1768	George Brandt
1698-1739	Charles Francois de Cisternay du Fay
1700-1782	Daniel Bernoulli - Switzerland; was the first to devise a quantitative kinetic theory of gases.
1706-1790	Benjamin Franklin - American statesman and philosopher; experimented with electricity; introduced the terms "positive" and "negative", instrumental in establishing the American Philosophical Society of Philadelphia, the first U.S. science society; showed that electricity could magnetize and demagnetize iron needles.
1711-1765	Mikhail Vasilievich Lomonosov
1722-1765	Axel Fredric Cronstedt
1728-1799	Joseph Black - Scottish chemist; laid the foundations for thermodynamics; worked with gases and showed that a gas could combine with a solid; recognized the importance of accurate weighing in chemical research.
1731-1810	Henry Cavendish - English physicist and chemist; discovered hydrogen (1766); discovered nitric acid.
1733-1804	Joseph Priestley - English clergyman and chemist; researched the relation among plants, animals and air; discovered hydrochloric and sulfuric acid (1775); isolated oxygen (1774); obtained water by igniting hydrogen and oxygen; made seltzer water by dissolving carbon dioxide in water.
1735-1784	Torbern Olof Bergman
1736-1806	Charles Augustin de Coulomb - French physicist; discovered the law of force between two charged bodies. After his graduation from the Ecole du Genie at Mezieres in 1761, he served as a military engineer in the West Indies and in other obscure French posts. In 1781 he was permanently stationed in Paris and was able to devote more time to research.Coulomb then turned his attention to physics and published (1785-91) seven memoirs on electricity and magnetism. He adapted a torsion balance to measure electrical forces and demonstrated (1785) the inverse-square law for attractive and repulsive forces in both electricity and magnetism, and he later showed that the force is also proportional to the product of the charges--a relationship now called Coulomb's Law. Coulomb may be considered to have extended Newtonian mechanics to a new realm of physics. The unit of electrical charge is named for him.
1736-1819	James Watt
1737-1798	Luigi Galvani - Italian physician and physicist; researched the relation between animal organisms and electricity; produced an electric current using a circuit made up of dissimilar metals; this type of electric current production, using two metals in a moist environment, is known as "galvanism".
1737-1816	Louis Bernard Guyton de Morveau
1742-1786	Karl Wilhelm Scheele - Scheele was a pharmacist-chemist famous for discovering chlorine. He also prepared oxygen but didn't receive credit because he hadn't published his work in a timely manner. Instead an English scientist named Joseph Priestly is credited with the discovery of oxygen..Scheele is also famous for finding many different acids, all organic. His discoveries include the following acids: tartaric, gallic, oxalic, citric, malic, lactic, and prussic. He was very tedious in his investigation. He also discovered copper arsenate, hydrogen sulfide gas, hydrofluoric acid, and hydrocyanic.
1743-1794	Antoine Laurent Lavoisier - French chemist; stated the first version of the law of conservation of matter; recognized and named oxygen (1778); disproved phlogiston theory; helped to reform chemical nomenclature. Often referred to as the father of modern chemistry. He was the first to grasp the true explanation of combustion. Lavoisier contended that fire was the result of rapid union of the burned material with oxygen. Nothing, however, he maintained, was lost through this action. His theory directly opposed the phlogistic notion that combustible bodies lost something when burned. Founded on Lavoisier's oxygen theory, a new system of nomenclature was evolved; one which held that oxygen was an essential constituent of all acids. This we know today to be erroneous. His theories were the basis for great advances in chemistry. As a young man of many interests, he studied astronomy, botany, and mathematics, as well as chemistry at the College Mazarin near his Paris home. Of key significance in his later life was his study of law and his admission to the bar. This led to an interest in French politics, whereupon he obtained a position as tax collector at the age of 26. While in government work he helped develop the metric system to secure uniformity of weights and measures throughout France. His governmental interests, however, eventually proved his undoing. As one of 28 French tax collectors Lavoisier was branded a traitor by revolutionists in 1794 and guillotined at the age of 51. Ironically, Lavoisier was one of the few liberals in his position and had striven for many years to alleviate the hardships of the peasants.
1743-1817	Martin Heinrich Klaproth
1745-1818	Johann Gottlieb Gahn
1745-1827	Alessandro Volta - Italian physicist; physics professor; experimented with electrical forces; invented first practical battery using cells made from two kinds of metals; this verified his theory of differing electrical potentials for unlike metals; electric potential difference is known as voltage and its unit is the Volt (V).
1746-1813	Peter Jacob Hjelm
1746-1823	Jacques-Alexandre-Cesar Charles - French chemist, physicist, and inventer; invented the hydrogen balloon (1783); developed Charle's Law which states the relationship between temperature and the volume of a gas (1787).
1748-1822	Claude Louis Berthollet
1749-1819	Daniel Rutherford
1749-1827	Pierre Somon de Laplace
1753-1815	William Nicholson
1754-1826	Joseph Louis Proust
b.ca. 1757	Marie-Anne Lavoisier - French linguist; translated the work of English chemists, drew Antoine's sketches and illustrations, kept his notes and published his final manuscript after his death.
1755-1809	Antoine Francois de Fourcroy
1760-1852	Johan Gadolin
1761-1815	Smithson Tennant
1762-1807	Jeremias Benjamin Richter
1764-1833	Gottlieb Sigismund Kirchhoff
1765-1833	Joseph Nicephore Niepce
c.1765-1847	Charles Hatchett
1766-1828	William Hyde Wollaston - English physician and chemist; discovered palladium and rhodium through his work with platinum metals (1803); invented the reflecting goniometer which measured the angles between crystal faces (1809).
1766-1844	John Dalton - English chemist and physicist; professor of mathematics and natural philosophy (1793); developed atomic theory; his theory (1805) accounts for the law of conservation of mass, law of definite proportions and law of multiple proportions; produced the first table of atomic weights; colorblind and mostly self-taught.
1767-1813	Anders Gustaf Ekebert
1768-1840	Anthony Carlisle
1773-1829	Thomas Young
1773-1858	Robert Brown
1774-1836	William Henry - English chemist; formulated Henry's  Law which states: the amount of a gas that will be absorbed by water increases as the gas pressure increases.
1774-1862	Jean Baptiste Biot
1775-1812	Etienne Louis Malus
1776-1856	Amedeo Avogadro - His hypothesis stated that equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules (1811).
1777-1838	Bernard Courtois
1777-1857	Louis Jacques Thenard
1778-1829	Humphry Davy - (Also See)
1778-1850	Joseph Louis Gay-Lussac - French chemist and physicist; developed the law of volumes concerning the combination of gases; discovered boron.
1779-1848	Jons Jakobs Berzelius - Swedish physician and chemist; discovered cerium, selenium, lithium, silicon, titanium and thorium; coined the terms "isomer" and "isomerism"; published a revised version of the periodic table with atom weights very close to today's table (1828); proposed system of elemental symbols and chemical notation.
1780-1849	Johann Wolfgang Dobereiner - German chemist; recognized the catalytic property of platinum; recognized the relationship between the elements and their atomic weight; made the earliest known attempt to organize the elements by their properties.
c.1781-1859	John Walker
1785-1838	Pierre Louis Dulong
1785-1859	William Prout
1786-1889	Michael Eugene Chevreul - French chemist; studied the composition of fats which led to the investigation of new compounds.
1787-1826	Joseph von Fraunhofer
1788-1827	Augustin Jean Fresnel
1789-1851	Louis-Jacques-Mande Daguerre - French artist and inventor; developed the daguerreotype photochemical process.
1791-1820	Alexis Therese Petit
1791-1867	Michael Faraday - English chemist and physicist; developed a process for liquefying chlorine; discovered benzene; introduced the laws of electrolysis (1833); developed a primitive electric motor; developed the voltmeter and the coulometer; devised terminology used in electrochemistry in collaboration with William Whewell.
1794-1863	Eihardt Mitscherlich
1794-1866	William Whewell
1797-1832	Nicolas Leonard Sadi Carnot
1797-1858	Carl Gustav Mosander
1799-1868	Christian Friedrich Schonbein
1800-1860	Charles Goodyear - American inventor; developed a process for vulcanization of rubber.
1800-1877	William Henry Fox Talbot
1800-1882	Friedrich Wohler (Woehler) - German chemist; professor of chemistry (1836-1882); synthesized the first organic compound (urea).
1800-1884	Jean-Baptist-Andre Dumas - French chemist; studied periodicity; developed method for determining vapor densities; isolated methanol; developed method for determining he nitrogen content of organic compounds.
1801-1868	Julius Plucker
1802-1850	Germain Henri Hess
1802-1876	Antoine Jerome Balard
1802-1887	Jean-Baptist Boussingault - French agricultural chemist; studied the nutritive value of foods fed to domestic animals.
1803-1873	Justin von Liebig
1805-1869	Thomas Graham - Scottish chemist; studied diffusion of gases which led to the formulation of Graham's Law; developed a process to separate crystalloids from colloids, which he named "dialysis"; did research using phosphoric acid; studied diffusion of liquids.
1807-1853	Auguste Laurent
1810-1878	Henri Victor Regnault
1811-1899	Robert Wilhelm Bunsen - German chemist; helped to develop the spectroscope; introduced the Bunsen burner that was developed by his laboratory assistant, Peter Desaga (1855); discovered the elements cesium (1860) and rubidium (1861).
1812-1888	Ascanio Sobrero
1813-1878	Claude Bernard - French physiologist; studied biochemical phenomena.
1813-1885	Thomas Andrews
1813-1891	Jean Servais Stas
1813-1898	Henry Bessemer - English engineer and inventor; developed an inexpensive steel-making process that burned off the impurities in molten pig iron through the use of a hot-air blast.
1814-1878	Julius Robert von Mayer - Mayer was born in the town of Heilbronn, Germany. He was a German physician and physicist. He and James Joule shared the credit for the discovery of the universal law of conservation of energy, or the first law of thermodynamics. This principle says that energy cannot be destroyed, energy in other forms tends to be converted to heat energy, and that a pure crystal at absolute zero would have a completely ordered arrangement of atoms. There are three other ways to express this law: Energy may change its form, but it cannot be created nor destroyed. When work is transformed into heat, or heat into work, the quantity of work is mechanically equivalent to the quantity of heat. The heat entering a system is equal to the increase in energy of the system plus the external work done by the system during the entry. Mayer published an article on heat and energy in 1842. Joule, an English physicist, made the same discovery while working independently. There is another law of Thermodynamics that goes along with the universal law of conservation of energy. It is the Law of Degradation of Energy which states that it is impossible to completely convert a given amount of heat energy into an exact amount of another form.
1814-1879	Heinrich Geissler
1815-1848	Horace Wells - American dentist; first to experiment with nitrous oxide as an anesthetic (1844).
1817-1884	Charles Adolphe Wurtz
1818-1881	Henri Etienne Sainte-Claire Deville
1818-1884	Adolph Wilhelm Herman Kolbe
1818-1989	James Prescott Joule  - English physicist; determined the mechanical equivalent of heat; proposed Joule's Law which describes the rate at which heat is produced by an electric current.
1818-1892	August Wilhelm von Hofmann
1819-1880	Edwin Laurentine Drake
1820-1886	Alexandre Emile Beguyer de Chancourtois
1820-1893	John Tyndall - Irish physicist; studied the diffusion of light by large molecules and dust, known as the Tyndall effect.
1821-1894	Hermann Ludwig Ferdinand von Helmholtz - German physicist, anatomist and physiologist; developed principle of conservation of energy; studied nerve cells and fibers and determined the speed of nerve impulses; investigated sight and hearing.
1822-1888	Rudolph Julius Emmanuel Clausius - German mathematical physicist; restated the second law of thermodynamics; coined the term "entropy".
1822-1895	Louis Pasteur - French chemist and microbiologist; developed the process of pasteurization.
1823-1883	Charles William Siemens - English industrialist; born in Germany; improved the regenerative furnace used in the process of making steel.
1824-1887	Gustav Robert Kirchhoff
1824-1904	William Williamson
1824-1907	William Thompson (Lord Kelvin) - English mathematician and physicist; derived the second law of thermodynamics; recognized the existence of absolute zero; proposed the Kelvin temperature scale (1851).
1824-1907	Pierre Jules Cesar Janssen
1824-1914	Johann Wilhelm Hittorf
1825-1899	Edward Frankland
1826-1909	Hans Peter Jorgen Julius Thomsen
1826-1910	Stanislao Cannizzaro
1826-1911	George Johnstone Stoney
1827-1902	Frederick Augustus Abel
1827-1907	Marcelin Berthelot - French chemist; synthesized organic compounds.
1828-1886	Alexander Mikhailovich Butlerov
1828-1914	Joseph Wilson Swan - developed a process for making nitrocellulose fibers used in early electric lamps (1933).
1829-1886	Friedrich August Kekule von Stradonitz - German chemist; demonstrated that carbon formed four bonds and that this could account for the formation of isomers (1858)
1830-1895	Julius Lothar Meyer
1830-1901	Francois Marie Raoult - formulated Raoult's Law  which states that colligative properties are determined by the number of particles in solution rather than by the type of particle in solution. The properties so affected are vapor pressure, freezing point, boiling point, and the rate of diffusion through a membrane.
1831-1879	James Clerk Maxwell - Scottish physicist; developed the field theory of electricity and magnetism; developed electromagnetic wave theory of light; developed a theory on viscosity of gases based on the statistical behavior of gas molecules.
1831-1892	Archibald Scott Couper
1832-1913	Louis Paul Cailletet
1832-1919	William Crookes - English chemist and physicist; His investigations of the photographic process in the 1850s motivated his work in the new science of spectroscopy. Using its techniques, Crooks discovered (1861) the element thallium, which won him election to the Royal Society. His efforts in determining the weight of thalium in an evacuated chamber led to his research in vacuum physics.Crooks invented the radiometer in 1875 and, beginning in 1878, investigated electrical discharges through highly evaculated "Crookes tubes." These studies laid the foundation for J. J. Thomson's research in the late 1890's concerning discharge-tube phenomena. At the age of 68, Crookes began investigating the phenomenon of radioactivity, which had been discovered in 1896, and invented a device that detected alpha particles emitted from radioactive material. Crookes maintained an interest in agriculture and warned in 1898 that the world's population would face starvation unless new fertilizer sources were discovered. He was also interested in psychic phenomena. He was knighted in 1897.
1833-1896	Alfred B. Nobel - Swedish engineer, chemist and industrialist; commercially manufactured chemical explosives throughout the world and did other chemical research; manufactured glyceryl nitrate - nitroglycerine (1862); the difficulty and danger of handling liquid nitroglycerine led him to experiment with ways of making it safer; he mixed nitroglycerine with powder, kieselguhr, and called it "dynamite" (1866); received a patent for dynamite (1867); establish a fund in his ill for the annual Nobel Prizes, awarded in the areas of chemistry, physics, physiology or medicine, literature and international peace.
1833-1900	Peter Waage
1834-1907	Dmitri Ivanovich Mendeleev - Russian chemist; developed the periodic table by placing the elements in order of increasing atomic weight (1869); predicted the existence and properties of elements that would fill the gaps left in his chart (1871); these elements were discovered between 1875 and 1885.
1835-1902	Johannes Adolf Wislicenus
1835-1917	Johann Friedrich Wilhelm Adolf von Baeyer
1836-1902	Cato Maximillian Guldberg
1836-1920	Joseph Norman Lockyer
1837-1898	John Alexander Reina Newlands
1837-1920	John Wesley Hyatt - American inventor and businessman; developed celluloid.
1837-1923	Johannes Diderik Van der Waals
1838-1904	Clemens Alexander Winkler
1838-1906	Friedrich Konrad Beilstein
1838-1907	William Henry Perkin- English chemist; produced first synthetic dye, mauve (1856).
1838-1912	Paul Emile Lecoq de Boisbaudran
1838-1916	Ernst Mach
1839-1903	Josiah Willard Gibbs - American physicist; research let to basic theories for physical chemistry; stated the Phase Rule of thermodynamics.
1839-1924	Louis-Marie-Hilaire Bernigaud, Count of Chardonnet - developed a process for making silk like fiber, later called rayon (1878).
1840-1899	Lars Fredrick Nilson
1840-1905	Per Theodor Cleve
1841-1927	Karl Graebe
1842-1919	John William Strutt (Lord Rayleigh)
1842-1923	James Dewar
1844-1906	Ludwig Boltzmann
1845-1920	Wilhelm Pfeffer
1845-1923	Wilhelm Roentgen - German physicist; studied the transmission and photographic capabilities of rays he called "x rays" (1895); received the first Nobel Prize (1901).
1846-1927	Ira Remsen - American chemist and educator; carried out investigations in both organic and inorganic chemistry.
1846-1929	Raoul Pictet
1847-1930	Joseph Achille Le Bel
1847-1931	Otto Wallach - German chemist; research on chemical composition of camphors, perfumes and essential oils.
1848-1897	Viktor Meyer
1848-1916	Friedrich Ernst Dorn
1850-1930	Eugen Goldstein
1850-1936	Henri Louis Le Chatelier - French industrial chemist; in 1888 made the observation: "Any change in one of the variables that determines the state of a system in equilibrium causes a shift in the position of equilibrium in a direction that tends to counteract the change in the variable under consideration."
1852-1907	Ferdinand Frederic Henri Moissan
1852-1908	Antoine-Henri Becquerel - French physicist; discovered natural radioactivity (1896); shared the Nobel Prize for physics for this discovery (1903).
1852-1911	Jacobus Hendricus Van't Hoff
1852-1916	William Ramsay - English chemist; president of the Society of Chemical Industry; shared discovery of argon (1894), Krypton (1898), and xenon (1898); independently discovered helium on earth (1895); received Nobel Prize for chemistry for discoveries of these rare, or "noble" elements (1904).
1852-1919	Emil Hermann Fischer - German organic chemist; analyzed structures of carbohydrates, proteins, enzymes and amino acids.
1853-1926	Heike Kamerlingh Onnes
1853-1932	Friedrich Wilhelm Ostwald
1854-1907	Hendrik Willem Bakhius Roozeboom
1854-1915	Paul Ehrlich - German chemist and bacteriologist; proposed a chemical explanation of immunity.
1854-1932	George Eastman
1856-1940	Joseph John Thomson - English physicist; researched atomic structure; discovered that atoms contained particles which he called "electrons"; developed the "plum pudding" or "raisin muffin," model of the atom which consisted of electrons embedded in a positive sphere of matter (1904); received Nobel Prize for physics (1907); developed the mass spectrograph with Francis William Aston (1919).
1856-1931	Edward Goodrich Acheson
1857-1894	Heinrich Rudolf Hertz
1857-1925	Elwood Hayes
1858-1929	Carl Auer (Baron von Welsbach)
1858-1940	Robert Abbot Hadfield
1859-1906	Pierre Curie - French physicist; researched radioactivity, he and wife, Marie, discovered radium and polonium (1898); they shared the Nobel Prize for physics (1903) with Antoine-Henri Becquerel.
1859-1927	Svante August Arrhenius - Swedish physicist and chemist; originated the modern theory of ionization of electrolytes; received the Nobel Prize for chemistry (1903).
1862-1947	Philipp Eduard Lenard
1863-1914	Paul Louis Toussaint Heroult
1863-1914	Charles Martin Hall - American chemist and manufacturer; first to invent a practical electrolytic process to extract aluminum from ores; formed the Pittsburgh Reduction Company (1888) which eventually became the Aluminum Company of America, ALCOA.
1863-1944	Leo Hendrik Baekeland
1863-1949	Frederick Stanley Kipping
1864-1941	Walther Hermann Nernst
1864-1943	George Washington Carver - American agricultural chemist.
1866-1919	Alfred Werner
1866-1947	Moses Gomberg
1867-1934	Marie Curie - French physicist; researched radioactivity; she and husband, Pierre, discovered radium and polonium (1898); they shared the Nobel Prize for physics (1903) with Becquerel; Marie received the Nobel Prize for chemistry (1911).
1867-1952	Vladimir Nikolaevich Ipatieff
1868-1928	Theodore William Richards - American chemist - recognized during his lifetime as the leading authority in atomic-weight determinations. A Harvard University graduate, he served as full professor at Harvard from 1901 to 1928. Using superior gravimetric methods and applying physicochemical principles, he determined the atomic weights of a large number of elements with an accuracy never surpassed. His detection of the varying atomic weight of lead in 1913 coincided with the discovery of isotopes by Frederick Soddy. Richards was awarded the 1914 Nobel Prize for chemistry. (January 31, 1868 - April 2, 1928)
1868-1934	Fritz Haber
1868-1953	Robert Andrews Milikan
1869-1910	Richard Abegg
1869-1930	Fritz Pregl
1869-1940	Phoebus Aaron Theodor Levene
1870-1927	Bertram Borden Boltwod
1870-1939	William Jackson Pope
1870-1942	Jean Baptiste Perrin
1870-1954	Kotaro Honda
1870-1960	Georges Claude
1871-1937	Ernest Rutherford (Baron Rutherford of Nelson) (Lord Ruthorford) - British physicist from New Zealand; discovered several radioactive isotopes with colleagues (1899-1905); classified forms of radiation as alpha, beta, and gamma; received Nobel Prize for chemistry (1908); worked on submarine detection during WWII; developed atomic theory (1911); researched transmutational effects of alpha particles on gases (ca. 1919) and other elements.
1872-1919	Mikhail Semenovich Tsvett
1872-1938	Georges Urbain
1872-1942	Richard Willstatter
1873-1952	Nevil Vincent Sidgwick
1874-1940	Karl Bosch
1874-1949	Andre Louis Debierne
1874-1952	Chaim Weizmann - Russian-born chemist who worked in Great Britain.
1875-1946	Gilbert Newton Lewis - American physical chemist; developed atomic theory; proposed the octet rule and the electron dot method of showing valence electrons; important contributor to acid-base theory and thermodynamics.
1876-1946	Alfred Stock
1876-1959	Adolf Windaus
1877-1944	Charles Glover Barkla
1877-1945	Francis William Aston - English physicist and chemist - discovered in 1919 that stable elements of low atomic weight are mixtures of isotopes. Using a mass spectrograph, which he developed while working with Sir Joseph John Thomson in Cambridge, and for which he received the 1922 Nobel Prize for chemistry. Aston also found that the masses of most atoms could be expressed as whole numbers when compared with oxygen (mass 16). With a more accurate spectrograph, however, Aston detected in 1927 a slight deviation from this whole-number rule. By graphing an index of the deviation (called the packing fraction) against the closest whole-number mass of an element, Aston derived important information concerning its structure and stability. (September 1, 1877 - November 20, 1945)
1877-1956	Frederick Soddy - British physicist received (1921) the Nobel Prize for chemistry for the conception of isotopes and the displacement law of radioactive change. With Ernest Rutherford he developed the disintegration theory of radioactivity, which explained radioactivity as the decay of atoms to form other elements. Soddy proposed the isotope concept--that atoms could have the same chemical identity but different atomic weights. His displacement law of radioactive change suggests that an element emitting an alpha particle becomes a new element with a lower atomic number, whereas emission of a beta particle raises the element's atomic number. (September 2, 1877 - September 22, 1956)
1877-1957	Heinrich Otto Wieland
1878-1936	Julius Arthur Nieuwland
1878-1968	Lise Meitner - Austrian physicist; together with her nephew Otto R. Frisch, published a theoretical interpretation of nuclear fission in 1939; collaborated with Otto Hahn of Germany to discover protactinium (1917) the element from which actinium is formed; became head (1917-1938) of the physics department of the Kaiser Wilhelm Institute for Chemistry in Berlin; also collaborated with Hahn and Fritz Strassmann to accomplish the fission of uranium (1938); Fleeing Nazi persecution, she resumed her work at Sweden's Nobel Institute; her theoretical work helped clarify the relationships between beta and gamma rays and stimulated Hahn and Fritz Strassmann in their discovery of the fission of heavy nuclei..
1879-1947	Johannes Nicolaus Bronsted - Danish chemist, best known for his theory of acids and bases (1923), according to which an acid is a proton donor and a base is a proton acceptor. While professor (1908-1947) of physical and inorganic chemistry at the University of Copenhagen, he produced outstanding papers in thermodynamics (heat and its relationship to other forms of energy) and kinetics (the effect of forces upon the motion of material bodies.
1879-1955	Albert Einstein - American physicist born in Germany; explained Brownian movement; published a paper that explained the photoelectric effect (1905) which provided the foundation for quantum theory and resulted in the invention of the photoelectric cell; published his general theory of relativity (1915) which contained a new description of gravity; received the Nobel Prize for physics for his work in quantum physics (1921).
1879-1960	Max Theodor Felix von Laue
1879-1968	Otto Hahn - German chemist-physicist; shared the 1944 Nobel Prize with Fritz Strassmann in chemistry for their discovery of the fission of heavy nuclei (first to recognize nucleur fission). He began his research work in radiochemistry in Sir William Ramsay's laboratory at University College, London, 1904. There, in the process of extracting radium from a sample of barium salt, Hahn discovered radiothorium. He obtained a research position at McGill University with Sir Ernest Rutherford, and in 1905 he again exhibited his talent for discovery by finding radioactinium.Returning to Germany in 1906, Hahn was appointed professor at the University of Berlin in 1910. After he was named (1912) head of the radioactivity department at the Kaiser Wilhelm (later Max Planck) Institute, Hahn and Lise Meitner, his collaborator of 30 years who joined him in 1907, discovered more radioelements. In 1917 they discovered the most stable isotope of element 91 (protactinium), the substance that helped resolve the complex actinium series. Hahn then became involved in the identification of artifical radioactive materials and their decay patterns. In collaboration with Fritz Strassmann, Hahn discovered (1938) that the transformation of uranium (element 91) artificially induced by neutron bombardment produced barium (element 56). Because barium is far removed from the original parent element, this discovery was considered at the time contrary to all theoretical expectations. This phenomenon, known as fission, led directly to the development of the atomic bomb.
1881-1945	Hans Fischer
1881-1955	Alexander Fleming - Scottish bacteriologist; isolated lysozyme from tears (1922); observed a mold, he named penicillin, that prevented bacterial growth.
1881-1957	Irving Langmuir - American chemist; improved incandescent lamp (1913); received Nobel Prize for chemistry (1932) for his study of monomolecular films; experimented with cloud-seeding (1950); helped refine theory of chemical bonding.
1881-1965	Hermann Staudinger
1882-1945	Johannes Hans Wilhelm Geiger - German physicist; occasionally collaborated with Ernest Rutherford; helped to develop first successful counter of alpha particles (1908); improved design of this instrument became known as the Geiger counter (1928).
1882-1961	Percy William Bridgman
1882-1970	Max Born - German physicist; received the Nobel Prize for physics for his work in quantum mechanics (1954).
1884-1949	Friedrich Karl Rudolf Bergius
1884-1971	Theodor Svedberg - Swedish colloid chemist.
1885-1962	Niels Henrik David Bohr - Danish physicist; his model of atomic structure proposed that electrons orbit the nucleus in fixed orbits that are discrete energy states; received the Nobel Prize for physics for his work in atomic structure and radiation (1922).
1886-1950	Arthur Jeffrey Dempster
1886-1956	Clarence Birdseye - American inventor and businessman; developed method for preserving foods by quick-freezing (1916-1928); formed General Foods Company (1924).
1886-1975	Robert Robinson
1887-1915	Henry Gwyn-Jeffreys Moseley - English physicist; discovered Moseley's law of characteristic x-ray spectra of elements (1913); demonstrated that the number of electrons in an element is the same as the atomic number, establishing the significance of the atomic number.
1887-1961	Erwin Schroedinger - Austrian physicist; developed atomic theory of wave mechanics (1926); shared Nobel Prize for physics with P.A.M.Dirac (1933).
1888-1970	Chandrasekhara Venkata Raman - Indian physicist; developed a spectroscopic technique named after him (1928); the scattering effect of light that a compound causes during Raman spectroscopy gives information about its molecular structure; received Nobel Prize for physics (1930).
1888-1973	Selman A Waksman - American; soil bacteriologist; Professor of microbiology.
1889-1944	Thomas Midgley Jr.
1890-1984	John Rock - American obstetrician-gynecologist; performed first successful in vitro fertilization of a human ovum (1944).
1891-1957	Walther Wilhelm Bothe - German physicist, received the 1954 Nobel Prize for physics for developing and applying the coincidence method. Using this method, Bothe and Hans Geiger demonstrated (1924) that the conservation of momentum and energy is valid in certain elementary processes and discredited the hypothesis that these physical properties are conserved only statistically. In 1929, Bothe and Werner Kolhorster demonstrated the existence of high-energy particles in cosmic radiation, and the following year Bothe, with H. Becker, detected a new radiation, which James Chadwick identified as the neutron. Bothe taught physics in Berlin and Giessen and directed the Max Planck Institute at Heidelberg, Germany, from 1934 until his death. (January 8, 1891 - February 8, 1957)
1891-1974	Sir James Chadwick - English physicist; discovered the neutron; received the Nobel Prize for physics for this discovery (1935).
1892-1958	Louis-Victor de Broglie - French physicist; demonstrated mathematically that electrons and other subatomic particles exhibit wavelike properties (1927); this particle-wave duality was derived from the work of Albert Einstein and Max Planck; received Nobel Prize for physics (1929).
1892-1962	Arthur Holly Compton - American physicist; discovered the Compton Effect, which showed that a proton has momentum. He was awarded the Nobel prize for physics jointly with C.T.R. Wilson (1927).
1892-	Dmitri Vladimirovich Skobeltsyn - Russian physicist; obtained the first cloud-chamber photographs of cosmic rays. These showed that the rays either were, or produced,  many charged, high energy particles.
1893-	Christopher Ingold
1893-1981	Harlold Clayton Urey - was awarded the 1934 Nobel Prize for chemistry for the discovery and isolation of deuterium (heavy hydrogen). Because of this recognition as a Nobel laureate and his experience in isotope separation, Urey was brought into the wartime Manhattan Project as head of the gaseous-diffusion project for uranium separation. Soon after the war he began to speak out against the misuse of nuclear energy. His later research involved such diverse fields as geochemistry, astrophysics, and the origin of life.
1894-1970	Marietta Blau - Austrian physicist; was the first to use nuclear track plates.
1895-1964	Gerhard Domagk
1895-1982	William Francis Giauque - American physical chemisty; did significant work in chemical thermodynamics, particularly on the behavior of substances at very low temperatures, for which he was awared the 1949 Nobel Prize for chemistry.Giauque determined accurately the entropy of a large number of substances near absolute zero, and he proved that the third law of thermodynamics, which states that at absolute zero a perfect crystal has a zero entropy, was a fundamental law of nature. He also discovered how a strong magnet could be used to produce temperature very close to absolute zero.
1896-1937	Wallace Hume Carothers
1896-1957	Gerty Cori - American biochemist born in Czechoslovakia.
1897-1956	Irene Joliot-Curie - French physicist; daughter of Marie and Pierre Curie; discovered artificial radioactivity along with husband Frederic Joliet-Curie.
1897-1967	John Douglas Cockcroft - English physicist known for his early work with Ernest Walton on atomic particle accelerators, for which they received the 1951 Nobel Prize for physics. A graduate of Cambridge University (1934), Cockcroft served as professor of natural philosophy at Cambridge (1934-1946), director of the Atomic Energy Research Establishment (1946), and president of the University of Manchester Institute of Science and Technology. In 1932, Cockcroft and Walton achieved the first successful disintegration of atomic nuclei by artificial means. Using a voltage multiplier to generate 150,000 volts of electricity, they bombarded lithium atoms with accelerated protons to produce beryllium. The beryllium immediately split into two alpha particles, which were identified by bright scintillations on a zinc-sulfide screen and by the density of their tracks.
1897-1974	Patrick Maynard Stuart Blackett - English physicist; obtained the first cloud-chamber tracks of the induced transmutation of nitrogen and of other elements, and late made many cosmic-ray studies. He was awarded the Nobel prize for physics (1948).
1898-1941	Rudolf Schoenheimer
1898-1968	Sir Howard Walter Florey, Baron Florey - British pathologist and codiscoverer of penicillin. Born in Adelaide, Australia, and educated in medicine at the University of Adelaide, he later studied and taught in England. In 1935 he was appointed director of the Dunn School of Pathology, University of Oxford. Florey studied naturally occurring antibacterials, of which the Penicillum mold discovered by Sir Alexander Fleming seemed the most promising. In 1939 Florey and the German-British biochemist Ernst Boris Chain isolated the active agent, penicillin, from a fraction of the mold and formulated procedures for extraction and production. With British industries affected by World War II, Florey took his process to the United States, where private and government laboratories produced sufficient quantities to combat bacterial infection in wounded soldiers. For his work he was knighted in 1944, shared the Nobel Prize in physiology or medicine n 1945 with Chain and Fleming and was elected president of the Royal Society in 1960.
1898-1973	Karl Ziegler - German chemist; Nobel Laureate in Chemistry (1963) for their discoveries in the field of the chemistry and technology of high polymers.
1898-	Isidor Isaac Rabi - Austrian, American physicist; made prescise determinations of nuclear magnetic moments in beams of atoms by his radio frequency resonance method. He was awarded the Nobel prize for physics (1944).
1899-1975	Percy Lavon Julian - American chemist; researched the Calabar bean plant; successfully synthesized physostigmine, which was used to treat glaucoma (1935).
1899-1998	Thomas Hope Johnson - American physicist; in 1931 he obtained crystal deffraction of a beam of hydrogen atoms. In 1933 Johnson and Jabez Curry Street (1906-1989) observed that the cosmic-ray intensity from the west exceeded that from the east. This east-west asymmetry shows that there is an excess of positively charged particles in the primary cosmic-ray beam.
1900-1958	Frederic Joliot-Curie - French nuclear physicist; Nobel Laureate in Chemistry (1935) in recognition of the synthesis of new radioactive elements.
1900-1958	Wolfgang Pauli   - Austrian theoretical physicist; one of the founders of modern physics. He is most famous for his "Pauli exclusion principle." which states that no two electrons in an atom can have the same four quantum numbers. For his work in this area he was awarded the 1945 Nobel Prize for physics.While an undergraduate student in physics at Munich, Pauli wrote a comprehensive article on the theory of relativity that became the classic treatment of the subject. In 1924 he proposed a new quantum number (related to spin) for electrons, and the following year he enunciated the exclusion principle. In 1928, Pauli was named professor of theoretical physics at the Zurich Technical University, where, in 1931, he predicted that conservation laws demanded the existence of the neutrino, a particle later found. After being at Princton University during World War II, Pauli became a U.S. citizen, but he spent his last years in Zurich.
1900-1965	Paul Muller - Swiss chemist; discovered that dichlorodiphenyltrichloroethane or DDT, a known synthetic chemical substance, was useful as an insecticide (1939).
1900-1967	Richard Kuhn - Swiss chemist; Nobel Laureate in Chemistry (1938) for his work on carotenoids and vitamins. (Caused by the authorities of his country to decline the award but later received the diploma and the medal.)
1901-1954	Enrico Fermi - American physicist born in Rome; researched the transmutation of elements through neutron bombardment; his team produced the first controlled nuclear chain reaction at the University of Chicago; received the Nobel Prize for physics for the development of neutron-induced nuclear reactions (1938).
1901-1958	Ernest Orlando Lawrence - American physicist; received Nobel Prize for physics for the invention and development of the cyclotron "atom smasher" (1939).
1901-1967	Robert Jemison Van De Graaff - American physicist; constructed the first reliable, high voltage, electrostatic generator for nuclear research - "Van De Graaff Generator".
1901-1976	Werner Karl Heisenberg - German physicist; published the first theory of quantum mechanics (1925); postulated the "uncertainty principle (1927); received Nobel Prize for physics (1932).
1901-1978	Vincent du Vigneaud - American chemist; Nobel Laureate in Chemistry (1955) for his work on biochemically important sulphur compounds, especially for the first synthesis of a polypeptide hormone.
1901-1982	Rene Jules Dubos - American bacteriologist born in France.
1901-1994	Linus Carl Pauling - American biochemist; applied X-ray diffraction, electron diffraction and quantum mechanics to chemistry; developed theories of rare gas compounds; developed mechanistic theory of enzymes (1946); determined the physical structure of proteins as helical (1951); developed and applied some of the laws of structural chemistry in work with proteins; researched the structure of DNA; received Nobel Prize for chemistry(1954) for research of the nature of chemical bonds; received Nobel Prize for peace (1962) for work in banning nuclear weapons testing; received National Medal of Honor (1975); shared in the quantum mechanical development of valence and resonance theory; introduced concept of electronegativity; founded the Linus Pauling Institute of Science and Medicine (1973); researched Vitamin C and nutrition.
1901-2000	Louis LePrince-Ringuet - French physicist; obtained the first cloud chamber photograph of a meson-electron collision, from which the mass of the meson could be deduced.
1902-1971	Arne Wilhelm Kaurin Tiselius -  Swedish chemist; Nobel Laureate in Chemistry (1948) for his research on electrophoresis and adsorption analysis, especially for his discoveries concerning the complex nature of the serum proteins.
1902-1984	Paul Adrien Maurice Dirac  - English physicist; published Principles of Quantum Mechanics (1930); received Nobel Prize for physics for his research in wave mechanics (1933).
1902-1995	Eugene Paul Wigner - Hungarian physicist; published the first of a long series of important papers on the application of group theory in quantum mechanics. He was awarded the Nobel prize for physics jointly with Maria Mayer and J.H.D. Jenson (1963)
1903-1969	Cecil Frank Powell - English physicist; discovered the pi-meson. Powell was awarded the Nobel prize for physics in 1950.
1903-1979	Giulio Natta - Italian Chemist; investigated catalytic reactions like the synthesis of methanol, of formaldehyde from methanol and of butylaldehyde from propylene, which were used on an industrial scale. He also worked on synthetic rubber and on the polymerisation of olefins with organometallic catalysts developed by Karl Ziegler by which he obtained polypropylenes of highly regular molecular structure. Awarded the Nobel Prize (1963) in chemistry, jointly  with Karl Ziegler.
1903-1995	Ernest Thomas Sinton Walton - Irish physicist; shared the 1951 Nobel Prize for physics with Sir John D. Cockcroft for achieving (1932) the first artificial transmutation of elements. Walton received his Ph.D. from Trinity College, Dublin, and joined Sir Ernest Rutherford at the Cavendish Laboratory, Cambridge University. There, with Cockcroft, he devised a method of accelerating protons with high voltages and used them to bombard lithium nuclei. He correctly interpreted the appearance of helium nucei as a result of the splitting of the lithium atoms.
1904-1967	Julius Robert Oppenheimer - American physicist; director of the Manhattan Project in Los Alamos, NM (1942-1945);director of The Institute for Advanced Study in Princeton, NJ (1947-1966).
1904-1968	George Gamow - Russian born American physicist - contributed significantly to increasing the knowledge of nuclear reactions within stars. After graduating (1928) from the University of Leningrad, he traveled in Europe. Gamow worked with Niels Bohr and Ernest Rutherford before coming to the United States in 1934. He taught at George Washington Univeristy until 1956; thereafter, he was a professor at the University of Colorado. (March 4, 1904 - August 19, 1968)
1904-1979	Otto Frisch - Austrian-English physicist; advanced the theory that uranium, when bombarded by neutrons, breaks into smaller atoms; coined the term "fission" for this process.
1905-1989	Emilio Segre - Italian born American physicist; known for his discovery of the antiproton, a negatively charged particle with the mass of a proton. In 1938 he began a life-long association with the University of California at Berkeley. From 1943 to 1946 he was a group leader at the Los Alamos division of the Manhattan Project. In 1955, Segre and Owen Chamberlain succeeded in producing and identifying the antiproton, for which they shared the Nobel Prize for physics in 1959. During his career, Sergre contributed to various fields of physics including study of the Zeeman effect, atomic spectroscopy, molecular beams, neutron physics, nuclear fission, and elementary particle physics. He collaborated with other physicists in the discovery of the elements technetium, astatine, and plutonium-239.
1905-1991	Carl David Anderson - American physicist; won the 1963 Nobel Prize for physics for his work on cosmic rays. In his cloud chamber studies, Anderson found decisive proof of the existence of the positron, a positively charged electron. In 1938 he and Seth H. Neddermeyer announced the discovery of the meson, a type of subatomic particle whose existence had earlier been predicted by Hideki Yukawa. In 1948, Cecil Powell found that in reality another meson, called the pi-meson, or pion, had the properties of Yukawa's model and decayed to the known meson discovered by Anderson.
1905-1993	Bruno Benedetto Rossi - Italian, American physicist; found and initial increase with thickness in the cosmic-ray intensity "transmitted" by an obsorber and explained this by cosmic-ray showers. A transition to decreasing intensities was observed beyond a certain thickness.
1906-1979	Sir Ernst Boris Chain - German, English biochemist;   Nobel Laureate in Medicine (1945) for the discovery of penicillin and its curative effect in various infectious diseases.
1906-	Luis F. Leloir - Argentine biochemist, born in France; received the Nobel Prize for chemistry for the discovery of sugar nucleotides and the biosynthesis of carbohydrates (1970).
1907-1981	Hideki Yukawa - Japanese nuclear physicist; postulated the existence of a short-lived subatomic particle that had a greater mass than the electron (1935); these intermediate particles were discovered two years later and named "mesotrons"; the term was then shortened to "mesons"; received Nobel Prize for physics (1949).
1907-1991	Edwin Mattison McMillan - American nuclear chemist; known for his contributions to the discovery of the transuranium elements neptunium and plutonium in 1940, and for developing the synchrotron in 1945. McMillan taught at the University of California at Berkeley from 1932 until retiring as professor emeritus in 1973; shared Nobel Prize for chemistry (1951) with Glenn T. Seaborg for the discovery and isolation of neptunium (93) of plutonium (94).
1907-1997	Sir Alexander Robertus Todd - Engish Biochemist;
1908-1980	Willard Frank Libby - American chemist; won the 1960 Nobel Prize for chemistry for his radiometric age-dating technique (1947), which uses the isotope carbon-14 to date archaeological specimens. He described his work in his book Radiocarbon Dating (1952; 2d ed., 1955). He taught at the University of California at Berkeley (1933-1945) and worked on the Manhattan Project (1941-1945). He then joined the Institute for Nuclear Studies at the University of Chicago (1945-1959) and finally the University of California at Los Angeles (1959-1980), where he directed the Institute for Geophysics and Panetary Physics. Libby twice served on the U.S. Atomic Energy Commission.
1908-2001	George Dixon Rochester - English physicist; discovered V-particles and hyperons.
1910-1994	Dorothy Crowfoot Hodgkin - English chemist; used X-ray crystallography to determine the structure of organic substances, including penicillins. She was the first person to discover the crystalline structure present in insulin, penicillin and vitamin B-12. For this discovery she was awarded a Nobel Prize.
1910-2002	Archer John Porter Martin - British biochemist; was awarded (with R.L.M. Synge) the Nobel Prize for Chemistry (1952) for development of paper partition chromatography, a quick and economical analytical technique permitting extensive advances in chemical, medical, and biological research.
1911-1988	Luis Walter Alvarez - American physicist; produced free protons with a particle accelerator; headed a team which designed a bubble chamber for detecting short-lived subatomic particles; received the Nobel Prize for physics (1968) for his 1960 discovery of these particles, called "resonances".
1911-1993	Polykarp Kusch - German physicist; made high precision determinations of the magnetic moment of the electron and found a small but theoretically significant difference between the predicted value and the experimental results. Kusch was awarded the Nobel prize for physics jointly with W.R. Lamb (1955).
1911-1997	Melvin Calvin - American chemist; awarded the 1961 Nobel Prize for chemistry for his study of photosynthesis, a process by which green plants absorb carbon dioxide and convert it into sugar and oxygen. After early work on the structure of organic compounds, Calvin began using radioactive carbon-14 in the 1940's to trace the various steps of photosynthesis. By 1957 he and his associate, James A. Bassham, had made a detailed analysis of the many reactions that take place. Calvin then turned his attention to formulating theories on the chemical evolution of life. He also condicted solar energy research, including studies of the possibilities of artificial photosynthesis. With Bassham, Calvin wrote The Photosynthesis of Carbon Compounds (1962) and Chemical Evolution (1969).
1912-1999	Glenn Theodore Seaborg - American chemist; shared the 1951 Nobel Prize for chemistry with Edwin McMillan for his participation in the discovery of most of the transuranium elements. Seabort received his Ph.D. in 1937 from the University of California at Berkeley, where he remained and did his early work on the isotopes of common elements. He later worked with McMillan, who isolated (1940) netpunium (atomic number 93), the first element beyond uranium. Seaborg and his associates later isolated the next transuranium element, plutonium. They also found a plutonium isotope, which promised to yield more fission energy than uranium.In 1942, Seaborg moved from Berkeley to the University of Chicago to find ways of producing plutonium for the atomic bomb project. His group discovered (1944) two new elements, americium (95) and curium (96). These discoveries helped to confirm Seaborg's hypothesis that the transuranium elements resembled one another and so formed a transition series (the actinide series) similar to the lanthanide series of rare earths. In 1946 he returned to Berkeley, and during the next twelve years he and his collaborators discovered six more transuranium elements: berkelium (97) in 1949, californium (98) in 1950, einsteinium (99) in 1952, fermium (100) in 1953, menelevium (101) in 1955, and nobelium (102) in 1958. The discovery of these elements was made possible by new particle accelerators that allowed heavy ions to be used as projectiles. Seabory was named (1958) chancellor of the Berkeley campus; in 1961 he became the first scientist to be chairman of the Atomic Energy Commission, The Lawrence Berkeley Laboratory in 1971, where he codiscovered (1974) element 106.
1913-	Willis Eugene Lamb, Jr. - American physicist; observed, during the course of spectral measurements of the fine structure of hydrogen in the microwave region, a small displacement (the "Lamb shift") of an energy level from its theoretical position as predicted by Dirac's quantum theory of the electron. Lamb was awarded the Nobel prize for physics jointly with P. Kusch (1955).
1913-	Philip Hague Abelson - colloborated in the discovery of neptunium (element 93)and devised a method for large-scale synthesis of enriched uranium for use as a power source in submarines. He served as director of the Carnegie Institution of Washington's Geophysical Laboratory from 1953 to 1971.
1913-2002	Martin D. Kamen - the discoverer of Carbon 14 and the originator of many of the techniques by which radioactive tracers are used to elucidate the chemistry of biological processes. He also carried out extensive research that underlies much of our understanding of the process of photosynthesis. For his discovery of Carbon 14 and work on tracers, Dr. Kamen received in 1996 the Enrico Fermi   award, the highest physics honor of the United States.
1914-1994	Richard Laurence Millington Synge - Nobel Laureate in Chemistry (1952), jointly with Archer John Porter Martin,  for their invention of partition chromatography.
1914-2002	Max Ferdinand Perutz - Nobel Laureate in Chemistry (1962), jointly with Sir John C. Kendrew, for their studies of the structures of globular proteins.
1914-	James Alfred Van Allen - American physicist; showed from the data obtained from instruments carried by artificial satellites that the earth is encircled by two zones, called Van Allen radiation belts, of high-energy charged particles whic are trapped by the earth's magnetic field.
1916-	Francis Harry Compton Crick - Nobel Laureate in Medicine (1962), jointly with James D. Watson and Maurice Wilkins, for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material.
1916-	Maurice Hugh Frederick Wilkins - Nobel Laureate in Medicine (1962), jointly with James D. Watson and Francis C. Crick,  for their discoveries concerning the molecular structure of nuclear acids and its significance for information transfer in living material.
1917-1979	Robert Burns Woodward - Nobel Laureate  in Chemistry (1965) for his outstanding achievements in the art of organic synthesis.
1917-2002	Martin Deutsch - Austrian, American physicist; experimentally confirmed the prediction of the existence of positronium.
1917-	William von Eggers Doering - obtained from the bark of the cinchona tree that is found in the Andes mountain range of Ecuador and Peru. They were probably discovered by Peruvian Jesuits, who introduced quinine into Europe around 1640. However the destruction of these trees to obtain quinine made them rare and so a way of making it synthetically was sought. This was found in 1944 by Robert Burns Woodward and Doering by synthesising quinine from coal tar. Quinine’s formula is C20H24N2O2.
1917-1997	Sir John Cowdery Kendrew -Nobel Laureate in Chemistry (1962), jointly with Max Ferdinand Perutz, for their studies of the structures of globular proteins.
1918-1998	Kenichi Fukui - Japanese chemist; applied the laws of quantum mechanics to chemical reactions involved in the development of effective drugs; shared Nobel Prize for chemistry with Roald Hoffman of the United States (1981).
1918-	Frederick Sanger - Nobel Laureate in Chemistry (1958) for his work on the structure of proteins, especially that of insulin.  Nobel Laureate in Chemistry (1980) for contributions concerning the determination of base sequences in nucleic acids.
1920-	Owen Chamberlain - American physicist; known for his joint discovery, along with Emilio Segre, of the antiproton, for which both received the 1959 Nobel Prize for physics. His graduate studies at the University of California were interrupted by World War II, at which time he joined the Manhattan Project to build the Atomic bomb. In 1955 Chamberlain and Segre discovered the antiproton, a subatomic particle with the same mass as the proton but with a negative charge. Since that time, he has investigated the interaction of antiproton or antimatter proton with hydrogen and deuterium.
1921-1999	Glenn T. Seaborg - American nuclear chemist; shared Nobel Prize for chemistry (1951) with Edwin Mattison McMillan for the discovery of plutonium (94).
1921-	Rosalyn S.Yalow - American biochemist; received the Nobel Prize for developing radioimmunoassays as peptide hormones (1977); second woman to be awarded the Nobel Prize for medicine and physiology.
1926-	Donald Arthur Glaser - American physicist; made the first bubble chamber. He was awarded the Nobel prize for physics in 1960.
1928-	James Dewey Watson - best known for his discovery of the structure of DNA (deoxyribonucleic acid), for which he shared with Francis Crick and Maurice Wilkins the Nobel Prize in Physiology or Medicine (1962). They proposed that the DNA molecule takes the shape of a double helix, an elegantly simple structure that resembles a gently twisted ladder. The rails of the ladder are made of alternating units of phosphate and the sugar deoxyribose; the rungs are each composed of a pair of nitrogen-containing nucleotides.
1929-	Rudolph L. Mossbauer - German physicist; predicted and found an extremely small frequency spread in the emission of low-energy gamma rays from nuclei bound in a crystal lattice. This effect results from giving the gamma-ray recoil momentum to the whole lattice instead of to an individual nucleus. The effect provides a very high precision frequency standard suitable for testing several predictions of the special and general theories of relativity. He was awarded the Nobel prize for physics jointly with R. Hofstadter (1961).
1936-	Samuel Chao Chung Ting - American physicist; discovered a subatomic particle which he named the "J particle" (1974); a parallel independent discovery of the same particle was made by Burton Richter who named it the "psi particle"' it is now known as the "J/psi particle"; shared Nobel Prize for physics with Richter (1976).
1936-	Yuan T. Lee - American physicist; developed a cross-beam molecular technique that gives detailed information about chemical reactions; designed a mass spectrometer detection system to monitor the collisions and scattering effects involved in this research technique; shared Nobel Prize for chemistry with Dudley R. Herschback (1986).