1841 in science

• Rev. Miles Joseph Berkeley demonstrates that Phytophthora infestans (potato blight) is a fungal infection. • Royal Botanic Gardens, Kew, first open to the public and William Hooker appointed director. • John Gould begins publication of A Monograph of the Macropodidae, or Family of Kangaroos. ==Chemistry==

• Theobromine is first discovered in cacao beans by Russian chemist Alexander Woskresensky. • Uranium is first isolated, by Eugène-Melchior Péligot. • Chemical Society of London founded by Thomas Graham. • Reinsch test for heavy metals discovered by Hugo Reinsch. ==Exploration==

• January 27 – The active volcano Mount Erebus in Antarctica is discovered and named by James Clark Ross. • January 28 – Ross discovers the "Victoria Barrier", later known as the Ross Ice Shelf. • Ross additionally discovers the Ross Sea, Victoria Land and Mount Terror. ==Geology==

• Hugh Miller publishes The Old Red Sandstone. • The first comprehensive geological map of France is published by Dufrénoy and Élie de Beaumont, the result of thirteen years of investigations. ==Human sciences==

• November 13 – Scottish surgeon James Braid attends his first demonstration of animal magnetism (given by Charles Lafontaine in Manchester, England) which leads to Braid's study of the subject he eventually calls hypnotism. ==Mathematics==

• Prussian mathematician Karl Weierstrass discovers but does not publish the Laurent expansion theorem. • English mathematician William Rutherford calculates an approximation of π to 208 decimal places of which the first 152 are correct. ==Physiology and medicine==

• Platelets are first described from microscopic observation by George Gulliver. ==Technology==

• February – H. Fox Talbot obtains a patent in the United Kingdom for the calotype process in photography. • April 16 – Loring Coes patents the screw type wrench commonly known as the monkey wrench in the United States. • April 24 – Squire Whipple patents the iron bowstring arch through truss bridge in the United States. • Draughtsman William Howe and pattern-maker William Williams of Robert Stephenson and Company in Newcastle upon Tyne originate Stephenson valve gear for the steam locomotive. • Joseph Whitworth introduces the British Standard Whitworth system of screw threads in his paper On a Uniform System of Screw Threads. • American artist John G. Rand invents the collapsible zinc oil paint tube, marketed by Winsor & Newton of London. ==Awards==

• Copley Medal: Georg Ohm • Wollaston Medal: Adolphe Theodore Brongniart ==Births==

• January 29 – Henry Morton Stanley (died 1904), explorer, journalist. • February 2 – François-Alphonse Forel (died 1912), pioneer in the study of lakes. • February 4 – Clément Ader (died 1926), engineer and inventor, airplane pioneer. • February 24 – Carl Gräbe, (died 1927) chemist. • March 6 – Alfred Cornu (died 1902), physicist. • August 4 – W. H. Hudson (died 1922), naturalist. • August 25 – Emil Theodor Kocher (died 1917), 1909 winner of the Nobel Prize in Physiology or Medicine • October 12 – Joseph O'Dwyer (died 1898), physician • October 26 – Theodor von Oppolzer (died 1886), astronomer. • November 3 – Eugen Warming (died 1924), botanist and founder of ecology. • December 29 – Rosalie Fougelberg (d. 1911), Swedish dentist ==Deaths==

• April 22 – Charles Barbier, inventor of a method of writing for the blind that was the inspiration for Braille. • May 16 – Marie Boivin, French midwife, inventor and obstetrics writer (born 1773) • May 31 – George Green (born 1793), English mathematician. • August 18 – Louis de Freycinet (born 1779), explored coastal regions of Western Australia. • September 9 – Augustin Pyramus de Candolle (born 1778), Swiss botanist. • October 28 – Johan August Arfwedson (born 1792), Swedish chemist. ==References==