The year 1845 in

science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

and

technology Technology is the application of knowledge to reach practical goals in a specifiable and reproducible way. The word ''technology'' may also mean the product of such an endeavor. The use of technology is widely prevalent in medicine, science, ...

involved some significant events, listed below.

Astronomy

* April –

Lord Rosse William Parsons, 3rd Earl of Rosse (17 June 1800 – 31 October 1867), was an Irish astronomer, naturalist, and engineer. He was president of the Royal Society (UK), the most important association of naturalists in the world in the nineteenth ...

discovers that the nebula

M51 M51 or M-51 may refer to: * M-51 (Michigan highway), a state highway in Michigan * M51 highway (Russia) * M51 (Cape Town), a Metropolitan Route in Cape Town, South Africa * M51 Skysweeper, an anti-aircraft gun * M51 MACI mine * M51 SLBM, a Fre ...

has a spiral structure. * September–October – Cornish mathematician

John Couch Adams John Couch Adams (; 5 June 1819 – 21 January 1892) was a British mathematician and astronomer. He was born in Laneast, near Launceston, Cornwall, and died in Cambridge. His most famous achievement was predicting the existence and position of ...

communicates to

James Challis James Challis FRS (12 December 1803 – 3 December 1882) was an English clergyman, physicist and astronomer. Plumian Professor of Astronomy and Experimental Philosophy and the director of the Cambridge Observatory, he investigated a wide ra ...

and

George Biddell Airy Sir George Biddell Airy (; 27 July 18012 January 1892) was an English mathematician and astronomer, and the seventh Astronomer Royal from 1835 to 1881. His many achievements include work on planetary orbits, measuring the mean density of the E ...

his calculations demonstrating that a body (

Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...

) is perturbing the orbit of

Uranus Uranus is the seventh planet from the Sun. Its name is a reference to the Greek god of the sky, Uranus (mythology), Uranus (Caelus), who, according to Greek mythology, was the great-grandfather of Ares (Mars (mythology), Mars), grandfather ...

. * November 10 –

Urbain Le Verrier Urbain Jean Joseph Le Verrier FRS (FOR) HFRSE (; 11 March 1811 – 23 September 1877) was a French astronomer and mathematician who specialized in celestial mechanics and is best known for predicting the existence and position of Neptune using ...

presents to the ''

Académie des sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the ...

'' in Paris a memoir showing that existing theories fail to account for the motion of Uranus. * Construction begins in

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

of the "

Leviathan of Parsonstown Leviathan of Parsonstown, or Rosse six-foot telescope, is a historic reflecting telescope of aperture, which was the largest telescope in the world from 1845 until the construction of the Hooker Telescope in California in 1917. The Rosse six-f ...

", a

telescope A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe ...

built by Lord Rosse.

Biology

* August–September – Previously unknown

Potato blight ''Phytophthora infestans'' is an oomycete or water mold, a fungus-like microorganism that causes the serious potato and tomato disease known as late blight or potato blight. Early blight, caused by ''Alternaria solani'', is also often called "po ...

strikes the

potato The potato is a starchy food, a tuber of the plant ''Solanum tuberosum'' and is a root vegetable native to the Americas. The plant is a perennial in the nightshade family Solanaceae. Wild potato species can be found from the southern Unit ...

crop in Ireland: start of the Great Famine.

Chemistry

* March 17 – Stephen Perry patents the

rubber band A rubber band (also known as an elastic band, gum band or lacky band) is a loop of rubber, usually ring or oval shaped, and commonly used to hold multiple objects together. The rubber band was patented in England on March 17, 1845 by Stephen P ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. *

Edmond Frémy Edmond Frémy (; 28 February 1814 – 3 February 1894) was a French chemist. He is perhaps best known today for Frémy's salt, a strong oxidizing agent which he discovered in 1845. Fremy's salt is a long-lived free radical that finds use as a s ...

discovers the

oxidizing agent An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or "Electron acceptor, accepts"/"receives" an electron from a (called the , , or ). In ot ...

Frémy's salt.

Exploration

* August –

John Franklin Sir John Franklin (16 April 1786 – 11 June 1847) was a British Royal Navy officer and Arctic explorer. After serving in wars against Napoleonic France and the United States, he led two expeditions into the Canadian Arctic and through ...

's expedition with HMS ''Erebus'' and HMS ''Terror'' to find the

Northwest Passage The Northwest Passage (NWP) is the sea route between the Atlantic and Pacific oceans through the Arctic Ocean, along the northern coast of North America via waterways through the Canadian Arctic Archipelago. The eastern route along the Arct ...

is last seen entering

Baffin Bay Baffin Bay ( Inuktitut: ''Saknirutiak Imanga''; kl, Avannaata Imaa; french: Baie de Baffin), located between Baffin Island and the west coast of Greenland, is defined by the International Hydrographic Organization as a marginal sea of the Arct ...

prior to its mysterious disappearance.

Medicine

* December 27 –

Anesthesia Anesthesia is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prevention of pain), paralysis (muscle relaxation), ...

is used in

childbirth Childbirth, also known as labour and delivery, is the ending of pregnancy where one or more babies exits the internal environment of the mother via vaginal delivery or caesarean section. In 2019, there were about 140.11 million births globall ...

for the first time, by Dr

Crawford Long Crawford Williamson Long (November 1, 1815 – June 16, 1878) was an American surgeon and pharmacist best known for his first use of inhaled sulfuric ether as an anesthetic An anesthetic (American English) or anaesthetic (British English; ...

Jefferson, Georgia Jefferson is a city in Jackson County, Georgia, United States. The population was 9,432 at the 2010 census, up from 3,825 at the 2000 census. As of 2019 the estimated population was 12,032. The city is the county seat of Jackson County. History ...

Physics

* September 13 –

Michael Faraday Michael Faraday (; 22 September 1791 – 25 August 1867) was an English scientist who contributed to the study of electromagnetism and electrochemistry. His main discoveries include the principles underlying electromagnetic inducti ...

discovers that an intense

magnetic field A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...

can rotate the plane of polarized light, the

Faraday effect The Faraday effect or Faraday rotation, sometimes referred to as the magneto-optic Faraday effect (MOFE), is a physical magneto-optical phenomenon. The Faraday effect causes a polarization rotation which is proportional to the projection of the m ...

. *

C. H. D. Buys Ballot Christophorus Henricus Diedericus Buys Ballot (; October 10, 1817 – February 3, 1890) was a Dutch chemist and meteorologist after whom Buys Ballot's law and the Buys Ballot table are named. He was first chairman of the International Meteor ...

confirms the

Doppler effect The Doppler effect or Doppler shift (or simply Doppler, when in context) is the change in frequency of a wave in relation to an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who d ...

for

sound wave In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid. In human physiology and psychology, sound is the ''reception'' of such waves and their ''perception'' by the ...

s. *

Kirchhoff's circuit laws Kirchhoff's circuit laws are two equalities that deal with the current and potential difference (commonly known as voltage) in the lumped element model of electrical circuits. They were first described in 1845 by German physicist Gustav Kirchhof ...

are first described by German physicist

Gustav Kirchhoff Gustav Robert Kirchhoff (; 12 March 1824 – 17 October 1887) was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects. He coine ...

Technology

* July 26–August 10 –

Isambard Kingdom Brunel Isambard Kingdom Brunel (; 9 April 1806 – 15 September 1859) was a British civil engineer who is considered "one of the most ingenious and prolific figures in engineering history," "one of the 19th-century engineering giants," and "one ...

’s iron

steamship A steamship, often referred to as a steamer, is a type of steam-powered vessel, typically ocean-faring and seaworthy, that is propelled by one or more steam engines that typically move (turn) propellers or paddlewheels. The first steamships ...

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...

'' makes the

Transatlantic Crossing Transatlantic crossings are passages of passengers and cargo across the Atlantic Ocean between Europe or Africa and the Americas. The majority of passenger traffic is across the North Atlantic between Western Europe and North America. Centuries ...

from

Liverpool Liverpool is a city and metropolitan borough in Merseyside, England. With a population of in 2019, it is the 10th largest English district by population and its metropolitan area is the fifth largest in the United Kingdom, with a popul ...

New York New York most commonly refers to: * New York City, the most populous city in the United States, located in the state of New York * New York (state), a state in the northeastern United States New York may also refer to: Film and television * '' ...

, the first screw propelled vessel to make the passage. * The

saxhorn The saxhorn is a family of valved brass instruments that have conical bores and deep cup-shaped mouthpieces. The saxhorn family was developed by Adolphe Sax, who is also known for creating the saxophone family. The sound of the saxhorn has a ...

family of valved

brass instrument A brass instrument is a musical instrument that produces sound by sympathetic vibration of air in a tubular resonator in sympathy with the vibration of the player's lips. Brass instruments are also called labrosones or labrophones, from Latin a ...

s is

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...

ed by

Adolphe Sax Antoine-Joseph "Adolphe" Sax (; 6 November 1814 – 4 February 1894) was a Belgian inventor and musician who invented the saxophone in the early 1840s, patenting it in 1846. He also invented the saxotromba, saxhorn and saxtuba. He played the fl ...

in France.

Publications

* January 14 – Physikalische Gesellschaft zu Berlin established and begins publishing ''

Fortschritte der Physik The German Physical Society (German: , DPG) is the oldest organisation of physicists. The DPG's worldwide membership is cited as 60,547, as of 2019, making it the largest physics society in the world. It holds an annual conference () and multiple ...

'' and ''

Verhandlungen The German Physical Society (German: , DPG) is the oldest organisation of physicists. The DPG's worldwide membership is cited as 60,547, as of 2019, making it the largest physics society in the world. It holds an annual conference () and multiple ...

''. * August 28 – The journal ''

Scientific American ''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many famous scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it. In print since 1845, it i ...

'' begins publication. *

Alexander von Humboldt Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 17696 May 1859) was a German polymath, geographer, naturalist, explorer, and proponent of Romantic philosophy and science. He was the younger brother of the Prussian minister, p ...

's ''Kosmos: Entwurf einer physischen Weltbeschreibung'' begins publication.

Awards

Copley Medal The Copley Medal is an award given by the Royal Society, for "outstanding achievements in research in any branch of science". It alternates between the physical sciences or mathematics and the biological sciences. Given every year, the medal is t ...

Theodor Schwann Theodor Schwann (; 7 December 181011 January 1882) was a German physician and physiologist. His most significant contribution to biology is considered to be the extension of cell theory to animals. Other contributions include the discovery of ...

Wollaston Medal The Wollaston Medal is a scientific award for geology, the highest award granted by the Geological Society of London. The medal is named after William Hyde Wollaston, and was first awarded in 1831. It was originally made of gold (1831–1845), t ...

for Geology: John Phillips

Births

*February 17 (Old Style March 1) –

Fyodor Pirotsky Fyodor Apollonovich Pirotsky or Fedir Apollonovych Pirotskyy ( ukr, Федір Аполлонович Піроцький; russian: Фёдор Аполлонович Пироцкий; -) was a Ukrainian engineer and inventor of the world's first ra ...

(died

1898 Events January–March * January 1 – New York City annexes land from surrounding counties, creating the City of Greater New York as the world's second largest. The city is geographically divided into five boroughs: Manhattan, B ...

), Ukrainian-born Russian military and electrical engineer and inventor. * March 3 –

Georg Cantor Georg Ferdinand Ludwig Philipp Cantor ( , ; – January 6, 1918) was a German mathematician. He played a pivotal role in the creation of set theory, which has become a fundamental theory in mathematics. Cantor established the importance of ...

(died

1918 This year is noted for the end of the First World War, on the eleventh hour of the eleventh day of the eleventh month, as well as for the Spanish flu pandemic that killed 50–100 million people worldwide. Events Below, the events ...

), Russian-born German

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

. * March 27 –

Wilhelm Röntgen Wilhelm Conrad Röntgen (; ; 27 March 184510 February 1923) was a German mechanical engineer and physicist, who, on 8 November 1895, produced and detected electromagnetic radiation in a wavelength range known as X-rays or Röntgen rays, an achiev ...

(died

1923 Events January–February * January 9 – Lithuania begins the Klaipėda Revolt to annex the Klaipėda Region (Memel Territory). * January 11 – Despite strong British protests, troops from France and Belgium occupy the Ruhr area, t ...

), German

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate caus ...

, discoverer of

X-rays An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 Picometre, picometers to 10 Nanometre, nanometers, corresponding to frequency, ...

Nobel laureate The Nobel Prizes ( sv, Nobelpriset, no, Nobelprisen) are awarded annually by the Royal Swedish Academy of Sciences, the Swedish Academy, the Karolinska Institutet, and the Norwegian Nobel Committee to individuals and organizations who make out ...

. * April 21 –

William Healey Dall William Healey Dall (August 21, 1845 – March 27, 1927) was an American naturalist, a prominent malacologist, and one of the earliest scientific explorers of interior Alaska. He described many mollusks of the Pacific Northwest of America, and w ...

(died

1927 Events January * January 1 – The British Broadcasting ''Company'' becomes the British Broadcasting ''Corporation'', when its Royal Charter of incorporation takes effect. John Reith becomes the first Director-General. * January 7 * ...

), American

malacologist Malacology is the branch of invertebrate zoology that deals with the study of the Mollusca (mollusks or molluscs), the second-largest phylum of animals in terms of described species after the arthropods. Mollusks include snails and slugs, clams, ...

and explorer. * May 4 –

William Kingdon Clifford William Kingdon Clifford (4 May 18453 March 1879) was an English mathematician and philosopher. Building on the work of Hermann Grassmann, he introduced what is now termed geometric algebra, a special case of the Clifford algebra named in his ...

(died

1879 Events January–March * January 1 – The Specie Resumption Act takes effect. The United States Note is valued the same as gold, for the first time since the American Civil War. * January 11 – The Anglo-Zulu War begins. * Janu ...

), English

geometer A geometer is a mathematician whose area of study is geometry. Some notable geometers and their main fields of work, chronologically listed, are: 1000 BCE to 1 BCE * Baudhayana (fl. c. 800 BC) – Euclidean geometry, geometric algebra * ...

. * May 16 –

Élie Metchnikoff Ilya Ilyich Mechnikov (russian: Илья Ильич Мечников; – 15 July 1916), also spelled Élie Metchnikoff, was a Russian zoologist best known for his pioneering research in immunology. Belkin, a Russian science historian, explains ...

(died

1916 Events Below, the events of the First World War have the "WWI" prefix. January * January 1 – The British Royal Army Medical Corps carries out the first successful blood transfusion, using blood that had been stored and cooled. * ...

), Russian-born

microbiologist A microbiologist (from Ancient Greek, Greek ) is a scientist who studies microscopic life forms and processes. This includes study of the growth, interactions and characteristics of Microorganism, microscopic organisms such as bacteria, algae, f ...

, Nobel laureate. * June 16 –

Heinrich Dressel Heinrich Dressel (June 16, 1845 in Rome – July 17, 1920 in Teisendorf) was a German archaeologist. He studied under Theodor Mommsen in Berlin, and later received his doctorate from the University of Göttingen with the thesis "''De Isidori Origi ...

(died

1920 Events January * January 1 ** Polish–Soviet War in 1920: The Russian Red Army increases its troops along the Polish border from 4 divisions to 20. ** Kauniainen, completely surrounded by the city of Espoo, secedes from Espoo as its own ma ...

), German

archaeologist Archaeology or archeology is the scientific study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, sites, and cultural landscap ...

. * July 4 –

Thomas Barnardo Thomas John Barnardo (4 July 184519 September 1905) was an Irish-born philanthropist and founder and director of homes for poor and deprived children. From the foundation of the first Barnardo's home in 1867 to the date of Barnardo's death, nea ...

(died

1905 As the second year of the massive Russo-Japanese War begins, more than 100,000 die in the largest world battles of that era, and the war chaos leads to the 1905 Russian Revolution against Nicholas II of Russia (Shostakovich's 11th Symphony i ...

), Irish-born

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

and

philanthropist Philanthropy is a form of altruism that consists of "private initiatives, for the Public good (economics), public good, focusing on quality of life". Philanthropy contrasts with business initiatives, which are private initiatives for private goo ...

. * September 11 –

Émile Baudot Jean-Maurice-Émile Baudot (; 11 September 1845 – 28 March 1903), French telegraph engineer and inventor of the first means of digital communication Baudot code, was one of the pioneers of telecommunications. He invented a multiplexed printi ...

(died

1903 Events January * January 1 – Edward VII is proclaimed Emperor of India. * January 19 – The first west–east transatlantic radio broadcast is made from the United States to England (the first east–west broadcast having been ...

), French

telegraph Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas p ...

engineer. * November 14 –

Ulisse Dini Ulisse Dini (14 November 1845 – 28 October 1918) was an Italian mathematician and politician, born in Pisa. He is known for his contribution to real analysis, partly collected in his book "''Fondamenti per la teorica delle funzioni di variabili ...

(died

), Italian mathematician.

Deaths

January 11 Events Pre-1600 * 532 – Nika riots in Constantinople: A quarrel between supporters of different chariot teams—the Blues and the Greens—in the Hippodrome escalates into violence. * 630 – Conquest of Mecca: The prophet Muhamma ...

–

Etheldred Benett Etheldred Anna Maria Benett (22 July 1776 – 11 January 1845) was an early English geologist often credited with being the first female geologist, having devoted much of her life to collecting and studying fossils that she discovered in South ...

(born

1776 Events January–February * January 1 – American Revolutionary War – Burning of Norfolk: The town of Norfolk, Virginia is destroyed, by the combined actions of the British Royal Navy and occupying Patriot forces. * January 1 ...

), British geologist. * March 13 –

John Frederic Daniell John Frederic Daniell FRS (12 March 1790 – 13 March 1845) was an English chemist and physicist. Biography Daniell was born in London. In 1831 he became the first professor of chemistry at the newly founded King's College London; and in 18 ...

(born

1790 Events January–March * January 8 – United States President George Washington gives the first State of the Union address, in New York City. * January 11 – The 11 minor states of the Austrian Netherlands, which took p ...

), English

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...

and

. * March 18 – '

Johnny Appleseed John Chapman (September 26, 1774March 18, 1845), better known as Johnny Appleseed, was an American pioneer nurseryman who introduced apple trees to large parts of Pennsylvania, Ohio, Indiana, Illinois, and Ontario, as well as the northern coun ...

' (John Chapman) (born

1774 Events January–March * January 21 – Mustafa III, List of Ottoman Sultans, Sultan of the Ottoman Empire, dies and is succeeded by his brother Abdul Hamid I. * January 27 ** An angry crowd in Boston, Massachusetts seizes, tars, and f ...

), American

nurseryman A nursery is a place where plants are propagated and grown to a desired size. Mostly the plants concerned are for gardening, forestry or conservation biology, rather than agriculture. They include retail nurseries, which sell to the general p ...

. * April 10 –

Thomas Sewall Thomas Sewall (April 16, 1786 – April 10, 1845) was an American physician, writer and academic. He gained notoriety for being convicted of body snatching, and later went on to become a professor. Early life Thomas Sewall was on April 16, 178 ...

(born

1786 Events January–March * January 3 – The third Treaty of Hopewell is signed, between the United States and the Choctaw. * January 6 – The outward bound East Indiaman '' Halsewell'' is wrecked on the south coast of Englan ...

), American

anatomist Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its ...

. * October 18 –

Dominique, comte de Cassini Jean-Dominique, comte de Cassini (30 June 174818 October 1845) was a French astronomer, son of César-François Cassini de Thury and great-grandson of Giovanni Domenico Cassini. Cassini was born at the Paris Observatory. He succeeded his fath ...

(born

1748 Events January–March * January 12 – Ahmad Shah Durrani captures Lahore. * January 27 – A fire at the prison and barracks at Kinsale, in Ireland, kills 54 of the prisoners of war housed there. An estimated 500 prison ...

), French

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

. *

Jean Henri Jaume Saint-Hilaire Jean Henri Jaume Saint-Hilaire (October 29, 1772 – 1845) was a French naturalist and artist, born in Grasse, France. Biography Born as ''Jaume'', he added ''Saint-Hilaire'' later. Some biographers indicate that this addition was to disting ...

(born

1772 Events January–March * January 10 – Shah Alam II, the Mughal Emperor of India, makes a triumphant return to Delhi 15 years after having been forced to flee. * January 17 – Johann Friedrich Struensee and Queen Carolin ...

), French

botanist Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek wo ...

References

{{reflist 19th century in science 1840s in science