Since the history of physics has been largely ignored in the text, we present the following chronology of biological, chemical and physical developments which are relevent to the material we have covered. Most entries reflect the first discovery or correct understanding of a phenomenon or principle.

- 4xxx BC --- Egyptians astronomically measure time
- 7xx BC --- India's use of anatomical models begins
- ----------- Babylonians and Chinese understand planetary orbits
- 5xx BC --- Alcmaeon (Greece) differentiates arteries from veins
- 585 BC --- Thales studies static electricity and magnetism
- 440 BC --- Democritus theorizes about atoms
- 35x BC --- Aristotle reasons that the Earth is spherical
- 240 BC --- Erastothenes computes the diameter of the Earth, suggests it orbits the sun
- 1025 AD --- Alhazen begins science of optics
- 1249 --- Bacon mentions lenses for improving vision
- 1275 --- Earliest recorded human dissection by William of Saliceto
- 1451 --- Nicholas of Cusa invents concave lenses
- 1490 --- da Vinci observes capillary action
- 1512 --- Copernicus understands that the planets orbit the sun
- 1540 --- Servetus discovers pulmonary circulation of blood
- 1568 --- Varolio studies the anatomy of the human brain
- 1583 --- Stevin understands hydrostatic pressure
- 1585 --- Stevin formulates law of equilibrium
- 1590 --- Galileo describes his experiments with gravity
- ----------- Janssen invents the microscope
- 1596 --- Galileo invents the thermometer
- 1600 --- Gilbert writes his treatise on electricity and magnetism
- 1603 --- Fabrici discovers valves in veins
- 1604 --- Kepler writes his treatise on optics
- 1608 --- Lippersley invents the telescope
- 1609 --- Kepler understands planetary motion quantitatively
- 1610 --- Beguin writes the first textbook on chemistry
- 1611 --- de Dominis explains the rainbow
- 1614 --- Santorio studies metabolism
- 1619 --- Harvey discovers circulation of blood
- 1621 --- Snel discovers the law of refraction
- 1622 --- Oughtred invents the slide rule
- 1643 --- Torricelli creates first artificial vacuum
- 1648 --- Pascal understands fluid pressure
- 1658 --- Swammerdam observes red blood cells
- 1660 --- Malpighi discovers capillaries
- 1661 --- Boyle defines chemical elements
- 1663 --- Steno teaches that the heart is a muscle
- 1665 --- Grimaldi explains diffraction
- ----------- Hooke describes cells
- ----------- Newton experiments with gravity, spectrum of light, invents differential calculus
- 1668 --- Wallis suggests momentum conservation
- 1674 --- Mayow describes nature of combustion
- 1675 --- Leibnitz invents integral calculus
- ----------- Romer discovers finite velocity of light
- 1678 --- Huygens discovers polarization of light
- 1680 --- Borelli describes mechanical nature of skeletomuscular system
- 1687 --- Newton understands force and gravity quantitatively
- 1690 --- Huygens publishes his (wave) theory of light
- 1704 --- Newton defends emission theory of light
- 1714 --- Fahrenheit develops temperature scale
- 1726 --- Hales measures blood pressure
- 1729 --- Gray differentiates between conductors and nonconductors
- 1738 --- Bernoulli understands pressure and velocity of fluids
- 1742 --- Celsius develops temperature scale
- 1745 --- von Kleist invents the capacitor
- 1748 --- Nollet discovers osmosis
- 1752 --- Franklin's experiments with electricity
- 1758 --- Marggraf invents chemical flame tests
- 1760 --- Black introduces heat capacity
- ----------- Lagrange formulates principle of least action
- 1762 --- Black introduces latent heat
- 1766 --- Cavendish discovers hydrogen less dense than air
- 1771 --- Galvani discovers electrical nature of nerve impulses
- 1775 --- Watt perfects the steam engine
- 1777 --- Coulomb invents torsion balance (measuring charge)
- ----------- Lavoisier discovers air is mostly O and N
- 1779 --- Priestley discovers photosynthesis
- 1784 --- Atwood accurately measures g
- 1786 --- Kalproth discovers uranium
- 1789 --- Lavoisier suggests conservation of mass
- 1790 --- France introduces the metric system
- 1800 --- Herschel discovers infrared rays
- ----------- Volta constructs the first battery
- 1801 --- Ritter discovers ultraviolet radiation
- ----------- Young performs the 2 slit experiment
- 1802 --- Dalton introduces atomic theory into chemistry
- 1807 --- Fourier invents his analysis
- 1811 --- Avogadro hypothesizes that gases are made up of molecules
- 1812 --- Kirchoff discovers catalysis
- 1814 --- Fraunhofer discovers spectral lines
- 1818 --- Fresnel theorizes that light is a transverse wave
- 1819 --- Oersted discovers electromagnetism
- 1821 --- Faraday proposes flux line picture for electricity and magnetism
- 1824 --- Carnot publishes his work on thermodynamics
- 1827 --- Brown discovers "Brownian Motion"
- ----------- Ohm formulates his law
- 1830 --- Brown discovers cell nucleii in plants
- 1831 --- Graham measures diffusion constants
- 1834 --- Babbage invents the principle of the programmable computer
- 1843 --- Joule determines machanical equivalent of heat
- 1847 --- Helmholtz publishes about the conservation of energy
- 1848 --- Thomson (Lord Kelvin) theorizes absolute zero
- 1849 --- Fizeau measures the speed of light
- 1850 --- Clausius formulates the entropy law
- ----------- von Helmholtz measures the speed of nerve impulses
- 1851 --- Thomson (Lord Kelvin) understands conservation and dissipation of energy
- 1852 --- Frankland discovers valence
- 1856 --- von Helmholtz understands physiological optics
- 1859 --- Bunsen and Kirchoff begin spectrum experiments
- ----------- Maxwell formulates his kinetic theory of gases
- 1860 --- Kirchoff theory of black body radiation
- 1862 --- Angstrom discovers H in the sun
- ----------- Helmholtz publishes about sound and hearing
- 1865 --- Loschmidt calculates Avogadro's number
- ----------- Maxwell theorizes that light and electromagnetism have the same source
- 1869 --- Mendeleyev formulates the periodic table of the elements
- 1873 --- van der Waals understands intermolecular forces
- 1878 --- Kuhne coins term enzyme
- 1879 --- Stefan understands thermal radiation
- 1883 --- Reynolds defines his number
- ----------- Thomson (Lord Kelvin) publishes about the size of atoms
- 1887 --- Hertz observes the photoelectric effect
- 1888 --- Hertz and Lodge independently prove that light and radio are the same phenomena
- 1891 --- Eotvos shows equality of gravitational and inertial mass
- 1895 --- Lorentz discovers his force
- ----------- Rontgen discovers x-rays
- 1896 --- Becquerel discovers radioactivity
- 1897 --- Braun invents the oscilloscope
- ----------- Rutherford discovers alpha and beta rays
- ----------- Thomson discovers the electron
- 1898 --- Benda discovers mitochondria
- 1900 --- Planck formulates quantum theory
- ----------- Richardson discovers electron emission
- ----------- Villard discovers gamma rays
- 1901 --- Curie measures heat equivalent of radioactivity
- 1903 --- Einthoven invents the EKG
- 1905 --- Einstein formulates photon theory of light and Special Theory of Relativity
- ----------- Hertzsprung relates stellar luminosity to spectra
- 1906 --- Nernst understands absolute zero
- 1907 --- Boltwood invents radioactive dating
- 1908 --- Perrin calculates the size of an atom
- 1911 --- Milliken measures e/m
- ----------- Rutherford's scattering experiments lead to his theory of atomic structure
- 1912 --- Laue discovers x-ray diffraction
- 1913 --- Bohr Theory of the atom
- ----------- Russel develops theory of stellar evolution
- 1914 --- Adams discovers white dwarf stars
- ----------- Hertzsprung identifies main sequence stars
- ----------- Rutherford suggests that H nucleus is fundamental "proton"
- 1915 --- Einstein formulates the General Theory of Relativity
- 1916 --- Schwarzschild theorizes black holes
- 1918 --- Secchi defines stellar spectral classes
- 1919 --- Aston builds mass spectrograph and discovers isotopes
- ----------- Rutherford discovers nuclear reactions
- 1921 --- Stern and Gerlach discover spin
- 1923 --- Compton identifies his wavelength
- ----------- Svedberg invents the ultracentrifuge
- 1924 --- de Broglie publishes his wave theory of matter
- 1925 --- Pauli introduces the exclusion principle
- 1926 --- Fermi links spin with statistics
- 1927 --- Thomson observes electron diffraction
- 1928 --- Hartree develops his approximation
- ----------- London and Heitler apply quantum mechanics to chemical bonds
- 1930 --- Dirac theorizes antimatter
- 1931 --- Fermi theorizes the neutrino
- 1932 --- Anderson discovers the positron
- ----------- Chadwick discovers the neutron
- ----------- Ruska builds first electron microscope
- 1934 --- Fermi theorizes weak interactions
- ----------- Zwicky theorizes neutron stars
- 1935 --- Yukawa theorizes strong interactions
- 1937 --- Rabi does first NMR experiments
- ----------- Tiselius invents electrophoresis
- 1938 --- Bethe understands solar fusion
- ----------- Krebs dscovers the TCA cycle
- 1939 --- Hahn and Strassman observe fission
- 1940 --- McMillan and Abelson manufacture first artificial element
- 1941 --- Lipmann understands high energy phosphates (ie., ATP)
- 1946 --- Bloch and Purcell make NMR practical as an observational instrument
- ----------- First electronic computer built at Pennsylvania University
- 1947 --- Libby does first carbon-14 dating
- 1948 --- Feynman develops QED (with Schwinger and Tomonaga)
- 1951 --- Hodgkin and Huxley and Katz work on transmission of nerve impulses
- 1952 --- First use of isotopes in medicine
- ----------- First artificial fusion reaction (U.S. Hydrogen bomb at Eniwetok Atoll)
- ----------- Franklin studies DNA with x-ray diffraction
- ----------- Sanger understands (first) protein structure
- 1953 --- Watson and Crick discover stucture of DNA
- 1956 --- Lee and Yang understand parity violation
- ----------- Neutrino discovered at Los Alamos
- 1957 --- Calvin discovers his cycle
- ----------- Esaki discovers tunneling in diodes
- 1960 --- First laser constructed by Maiman
- 1961 --- Gell-man and Ne'emen theorize quarks
- 1964 --- Fitch and Cronin do experiments leading to CPT theorem
- 1968 --- Development of Electroweak Model by Glashow, Salam and Weinberg
- 1972 --- Gell-man theorizes QCD (Quantum ChromoDynamics, about strong force)
- 1973 --- Gross, Politzer and Wilczek theorize asymptotic freedom
- 1974 --- First experimental evidence of quarks
- 1980 --- First Personal Computers
- 1983 --- W & Z bosons first observed
- 1988 --- First release of Mathematica
- 1994 --- Hubble Space Telescope confirms existance of black holes
- 1995 --- Top quark discovered

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©1996, Kenneth R. Koehler. All Rights Reserved. This document may be freely reproduced provided that this copyright notice is included.

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