1804 in science

The year 1804 in science and technology involved some significant events, listed below.

Chemistry

The drug morphine is isolated, and many elements are discovered, including cerium, iridium, osmium, palladium, and rhodium:
* William Hyde Wollaston discovers palladium, and how to make malleable platinum.
* Jöns Jakob Berzelius discovers cerium.
* The element iridium is discovered in the acid-insoluble residues of platinum ores by English chemist Smithson Tennant.
* The element rhodium is discovered by William Hyde Wollaston in crude platinum ore.
* The element osmium is discovered by the English chemist Smithson Tennant.

* German pharmacist Friedrich Sertürner isolates morphine from opium for the first time.

Exploration

* May 14 - The Lewis and Clark Expedition departs from Camp Dubois and begin their historic journey by traveling up the Missouri River

Geology

* Alexander von Humboldt discovers that the Earth's magnetic field decreases from the poles to the equator

Meteorology

* Joseph Louis Gay-Lussac and Jean Baptiste Biot study the atmosphere from a hot-air balloon

Technology

* Richard Trevithick produces his first railway locomotive

Awards

* Copley Medal: Smithson Tennant

Births

* March 8 - Alvan Clark, telescope manufacturer (d. 1887)
* July 20 - Richard Owen, anatomist and paleontologist (died 1892)
* September 14 - John Gould, zoologist (died 1881)
* October 24 - Wilhelm Eduard Weber, physicist (died 1891)
* December 10 - Carl Gustav Jakob Jacobi, mathematician (died 1851)
* Robert Schomburgk, explorer (died 1865)
* William Stokes, physician (died 1878)
* Heinrich Lenz, physicist (died 1865)
* Matthias Schleiden, biologist (died 1881)

Deaths

* February 6 - Joseph Priestley, chemist (born 1733)
* October 2 - Nicolas-Joseph Cugnot, engineer (born 1725)
* Pierre Méchain, astronomer (born 1744)