| 1801 |
John Dalton publishes his law of partial pressures
for gases. 
Three new chemical elements are discovered.
|
| 1803 |
John Dalton explains his atomic theory of matter.
Five more chemical elements are discovered.
|
| 1804 |
Nicholas de Saussure shows that plants need carbon
dioxide from the air and nitrogen from the soil. Up until
now it has been assumed that they get carbon from the soil.
The first canning factory is opened following the invention
of the process by Nicholas Appert, a French sweet
maker.
|
| 1806 |
The first amino acid - asparagine
- is discovered. |
| 1807 |
Chemicals are classified as either ORGANIC OR INORGANIC
by the Swedish chemist Jöns Jakob Berzelius.
The Danish physicist and chemist Hans Christian Oersted
starts looking for a connection between electricity and
magnesium.
|
| 1808 |
The English chemist Humphry Davy discovers barium,
strontium, calcium and suggests the existence of magnesium.
He also discovers boron at the same time as the French chemists
Joseph-Louis Gay-Lussac and Louis-Jacques Thénard.
Etienne-Louis Malus discovers polarised light.
|
| 1809 |
The French botanist and zoologist
Jean-Baptiste Lamarck states that animals evolved from
simple worms. He suggests that evolution comes about as organisms
acquire characteristics during their lifetime. These are then
passed on to their offspring. |
| 1810 |
The German doctor Samuel Hahnemann
publishes his book Organon of Rational Healing, in
which he explains the ideas behind a method of healing which
he calls "homeopathy". |
| 1811 |
Jöns Jakob Berzelius introduces a
system of chemical symbols which will form the basis of
the system still in use in the 21st century.
Amedeo Avogadro sets out his idea that equal volumes
of any gas at the same temperature and pressure contain
equal numbers of particles. This will become known as "Avogadro's
law".
In Dorset, England, Mary Anning (aged 11) discovers
the whole fossil skeleton of an ichthyosaur, a prehistoric
marine reptile which lived over 90 million years ago. Mary
will live all her life in Lyme Regis in Dorset, discovering
many other important fossil skeletons including the first
complete plesiosaur skeleton (in 1810) and the first Early
Jurassic pterosaur, Dimorphodon, in 1828.
|
| 1815 |
The French chemist Michel Chevreul shows that the
sugar in the urine of diabetics is glucose, an important
step in understanding the disease.
In Indonesia, Mount Tambora explodes, killing 12000 people.
The dust which goes into the air will lower air temperatures
around the world for more than a year.
Humphry Davy invents the safety lamp which can
be used in coal mines without triggering an explosion.
|
| 1816 |
Humphry Davy discovers
that platinum can act as a catalyst in certain types of chemical
reaction. |
| 1817 |
A pandemic of cholera begins
in India and spreads to East Africa and most of Asia, including
Japan and the Philippines. |
| 1818 |
Louis-Jacques Thénard
discovers hydrogen peroxide by accident. |
| 1819 |
The English chemist John Kidd
extracts naphthalene from coal tar. This is the first of many
useful substances to be discovered in coal tar, a thick black
liquid made when coal is heated to make coke and gas. |
| 1820 |
Hans Christian Oersted announces the discovery that
a magnetic needle is affected by a wire carrying an electric
current - the birth of the study of electricity and magnetism.
In France, André-Marie Ampère devises
one of the basic laws of electromagnetism, the RIGHT-HAND
rule.
|
| 1821 |
The English physicist and chemist
Michael Faraday reports his invention of the first
electric motor. |
| 1822 |
In Sussex, England, Mary Ann Mantell discovers the
first fossil to be recognised as a dinosaur. This happens
while she waits on the road outside the house of one of
her husband's patients. The creature is named "iguanodon"
by her husband, Gideon.
The English mathematician Charles Babbage develops
the Difference Engine, a machine for calculating values
of logarithms from 1 to 108,000. Although Babbage almost
finishes building his machine he cannot complete it because
he does not have enough money, even though he invests much
of his own personal fortune.
|
| 1823 |
Ampère develops a theory relating electricity
to magnetism. Although his ideas fit well with 21st century
models of electricity, his contemporaries are not at all
convinced by his work.
The Scottish chemist Charles Macintosh invents a
waterproof fabric using rubber dissolved in a chemical called
naphtha. The patented fabric is named after its inventor,
although usually with the spelling "mackintosh".
|
| 1824 |
The French physicist Nicholas Léonard Sadi Carnot
publishes his book Réflexions sur la Puissance
Motrice du Feu. This links work and heat, defines work
and gets close to the second law of thermodynamics. It also
proposes the idea of the internal combustion engine.
|
| 1825 |
Michael Faraday isolates benzene by the fractional
distillation of whale oil.
The German chemist Richard Erlenmeyer synthesises
lots of organic compounds and also invents a way of representing
single, double and triple bonds between atoms.
|
| 1826 |
The German anatomist Karl
Gegenbaur shows that all vertebrate cells arise from divisions
of the egg and sperm. |
| 1827 |
The German chemist Friedrich
Wöhler develops a new method to prepare aluminium
in pure form. Aluminium remains the most expensive metal on
Earth. During the 19th century some aluminium jewellery is
made. |
| 1828 |
Wöhler synthesises urea from inorganic compounds.
This disproves the idea that organic compounds can only
be made by living organisms under the influence of a "vital
force".
Caroline Lucretia Herschel receives the Royal Astronomical
Society's gold medal for her work on the star catalogues
of her brother and of the astronomer John Flamsteed.
|
| 1829 |
The term 'kinetic energy' is used for the first time.
Johann Schönlein describes the genetic blood
disease haemophilia.
|
| 1830 |
Mary Somerville's book The Mechanisms of the
Heavens popularises the work of Pierre Simon, Marquis
de Laplace. Born in Scotland, Mary is self-educated - nevertheless,
Laplace declares that she is the only woman to have understood
his work.
The Scottish geologist Charles Lyell publishes the
first volume of The Principles of Geology and starts
a massive study of the history of the Earth, showing that
it must be several hundred million years old.
In America Joseph Henry discovers the principle
of the dynamo before Michael Faraday - but he does not publish
his account until Faraday has published his.
|
| 1831 |
Charles Darwin joins the
crew of HMS Beagle as the ship's naturalist. This is supposed
to be for a two year voyage to map the coast of South America,
although the voyage will actually last for five years. |
| 1833 |
Charles Babbage conceives his Analytical Engine.
Only part of this machine was ever built. It was to have
been capable of storing instructions and performing mathematical
calculations, and would have used punched cards as a form
of memory.
At a meeting of the British Association for the Advancement
of Science, William Whewell uses the term 'scientist'
for the first time.
|
| 1834 |
Gabriel Gustav Valentin
(born of German and Swiss parents in Poland) and Jan Purkinje
(from Czechoslovakia) discover that the ovum is moved through
the oviduct by cilia. |
| 1835 |
Charles Darwin visits
the Galapagos Islands. |
| 1836 |
The German anatomist Heinrich Wilhelm Gottfried von
Waldeyer-Hartz discovers that the nervous system is
not a continuous system but that it is build up from separate
cells that do not actually touch each other.
The combine harvester is used for the first time in the
USA
In Germany Theodor Schwann discovers the first known
animal pepsin which acts on proteins in the stomach.
|
| 1837 |
Henri Dutrochet shows
that only the green parts of plants which contain chlorophyll
use carbon dioxide, and that they absorb carbon dioxide only
in the presence of light. |
| 1838 |
US Army surgeon William Beaumont
publishes the results of his experiments on digestion. These
have been carried out on a young Canadian man called Alexis
St Martin who received an accidental gunshot wound through
the stomach. Beaumont operated on St Martin, but part of his
stomach remained outside his body, covered only by a loose
flap of skin. By lifting the flap, Beaumont could observe
the process of digestion. He obtained samples of stomach contents
at various stages of digestion which he sent to doctors and
physiologists around the world for further study. |
| 1839 |
Jan Purkinje invents the
word 'protoplasm' for the contents of the cell. |
| 1840 |
The Italian physicist Giovanni
Battista Amici invents the oil immersion microscope. He
introduces a number of innovations which lead to microscopes
which can enlarge up to 6,000 times. This makes the understanding
of cells much easier. |
| 1841 |
Jöns Jakob Berzelius observes chemical
allotropes for the first time when he converts charcoal
into graphite.
The English biologist Richard Owen coins the term
"dinosaur" (meaning "terrible lizard") to describe
the fossil reptiles which were being discovered at this
time.
|
| 1842 |
The American surgeon Crawford
Williamson Long claims to have performed the first operation
using ether as an anaesthetic, while cutting out a tumour
from a patient's neck. However, he does not announce his results
until 1849. Meanwhile, William Morton (an American
dentist) makes the first public demonstration of ether as
an anaesthetic in 1846 and gets the credit for this development. |
| 1843 |
The English astronomer John
Couch Adams calculates the position of Neptune without
ever seeing it. He does this using the irregularities in the
orbit of Uranus, but remains uncertain about his calculations
until he is supplied with new data by the Astronomer Royal,
Sir George Biddell Airy. Airy does not take Adams's
claims very seriously, and does not begin searching for Neptune
until July 1846. Meanwhile the French astronomer Urbain
Jean Joseph Leverrier has done similar calculations, and
locates Neptune on September 23 1846. Leverrier
receives great recognition for his discovery, while Adams
is almost completely ignored. Despite this, the two men become
great friends. |
| 1844 |
It is shown for the first time that the egg is a cell,
and that all cells in an organism came from divisions of
the original egg cell.
The Scottish doctor Sir Patrick Manson suggests
that the mosquito might be the vector which spreads malaria.
|
| 1845 |
The German chemist Christian
Schönbein discovers nitrocellulose (gun cotton) in an
unorthodox way. He wipes up some spilled acid with his wife's
cotton apron which explodes and vanishes as it dries! |
| 1846 |
The German biologist, Hugo von Mohl, shows that
cytoplasm (called "protoplasm" at this time) is
the main component of living cells.
Chloroform is used as an anaesthetic in childbirth for
the first time.
|
| 1847 |
The Hungarian doctor Ignaz
Philipp Semmelweis shows that childbed fever is contagious.
By introducing handwashing between patients on his wards he
greatly reduced the number of deaths recorded, but few other
doctors took any notice. |
| 1848 |
The American astronomer Maria Mitchell is the first
woman elected to the American Academy of Science.
|
| 1849 |
Hormones are demonstrated for
the first time when Berthold implants testes onto castrated
cockerels and they then continue to act like entire cockerels,
mating and crowing. |
| 1850 |
The second law of thermodynamics is stated for the first
time by German physicist Rudolf Clausius.
The German botanist Ferdinand Julius Cohn shows
that the protoplasm in plant and animal cells is essentially
identical.
|
