| Dates | Characters | Theories and discoveries |
| 1800 | William Herschel | Infrared rays from the Sun |
| 1801 | Johann Ritter | Ultraviolet rays |
| 1801 | Johann von Soldner | Predicted Newtonian bending of light by sun |
| 1801 | Giuseppe Piazzi | First asteroid Ceres |
| 1801 | Humphry Davy | Electric arc |
| 1801 | Andres Manuel del Rio | Compounds of element vanadium |
| 1801 | Charles Hatchett | Element niobium in ores |
| 1802 | Heinrich Olbers | Second asteroid Pallas |
| 1802 | Anders Ekeberg | Element tantalum |
| 1802 | William Wollaston | Dark lines in solar spectrum |
| 1802 | William Herschel | Double stars are bodies in mutual orbit |
| 1802 | Thomas Young | Interference and wave description of light |
| 1802 | Humphry Davy | Electrochemistry |
| 1802 | Joseph Gay-Lussac | Relation of Volume to Temperature of gases at fixed pressure |
| 1803 | William Wollaston | Elements rhodium and palladium |
| 1803 | Smithson Tennant | Elements osmium and iridium |
| 1804 | John Dalton | Law of partial pressures, Dalton’s law |
| 1807 | Humphry Davy | Isolation of elements sodium and potasium |
| 1808 | Humphry Davy | Isolation of elements magnesium, strontium, barium and calcium |
| 1808 | Davy, Gay-Lussac & Thenard | Isloation of element boron |
| 1808 | Joseph Gay-Lussac | Law of gas volumes in chemical reactions |
| 1808 | John Dalton | Atomic theory of chemical reactions |
| 1808 | Etienne Malus | Polarisation of reflected light |
| 1809 | Simeon-Denis Poisson | Poisson brackets in mechanics |
| 1811 | Amedeo Avogadro | Molecular theory of gases and Avogadro’s law |
| 1811 | Jean-Baptiste Fourier | Harmonic analysis |
| 1811 | Bernard Courtois | Element iodine |
| 1812 | David Brewster | Behaviour of polarised light |
| 1814 | Joseph von Fraunhofer | Spectroscope invented |
| 1815 | William Prout | Atomic weights of elements are multiples of that for hydrogen |
| 1815 | Augustin Fresnel | Theory of light diffraction |
| 1816 | Joseph von Fraunhofer | Absorption lines in sun’s spectrum |
| 1817 | Young and Fresnel | Transverse nature of light |
| 1817 | Johan Arfvedson | Element lithium |
| 1817 | Friedrich Strohmeyer | Element cadmium |
| 1817 | Jöautns Berzelius | Element selenium |
| 1818 | Augustin Fresnel, | Ether as absolute rest frame |
| 1819 | Dulong and Petit | Relation of specific heats to atomic weight in 12 solid elements |
| 1820 | Andre Ampere | Force on an electric current in a magnetic field |
| 1820 | Hans Christian Oersted | An electric current deflects a magnetised needle |
| 1820 | Biot and Savart | Force law between an electric current and a magnetic field |
| 1821 | Thomas Seebeck | Thermocouple and thermoelectricity |
| 1821 | Joseph von Fraunhofer | Diffraction grating |
| 1821 | Michael Faraday | Plotted the magnetic field around a conductor |
| 1821 | Michael Faraday | First electric motor |
| 1822 | Andre Ampere | Two wires with electric currents attract |
| 1822 | Charles Babbage | A prototype calculating machine |
| 1822 | Mary Mantell | First dinosaur fossil |
| 1823 | Michael Faraday | Liquifies chlorine |
| 1823 | John William Herschel | Suggests identification of chemical composition from spectrum |
| 1823 | William Sturgeon | Electromagnets |
| 1823 | Heinrich Olbers | Why is the sky dark? |
| 1823 | Johann Schweigger | Galvanometer |
| 1824 | Sadi Carnot | Heat transfer goes from hot body to cold body |
| 1824 | Jöautns Berzelius | Element silicon |
| 1824 | Jöautns Berzelius | Isolation of element zirconium |
| 1825 | Hans Christian Oersted | Isolation of element aluminium |
| 1826 | Antoine-J. Balard | Element bromine discovered |
| 1827 | Georg Ohm | Electrical resistance and Ohm’s law |
| 1827 | Robert Brown | Brownian motion |
| 1828 | Friedrich Wohler | Isolation of element yttrium |
| 1829 | Johann Wolfgang | Triads of chemical elements |
| 1829 | Thomas Graham | Gas diffusion law |
| 1829 | Jons Berzelius | Element thorium discovered |
| 1830 | Charles Lyell | Proposition that Earth is several million years old |
| 1830 | Nils Sefstrom | Rediscovery and naming of vanadium |






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