1778 in science

Astronomy

• Lagrange delivers his treatise on cometary perturbations to the Académie française.

  Chemistry

• Molybdenum discovered by Carl Wilhelm Scheele.
• Antoine Lavoisier, considered "The father of modern chemistry", recognizes and names oxygen, and recognizes its importance and role in combustion.

  Earth sciences and exploration

• January 18 – On his third voyage, Captain James Cook, with ships HMS Resolution and HMS Discovery, becomes the first European to view the Hawaiian Islands in the Pacific Ocean.
• March 6 – October 24 – Captain Cook explores and maps the Pacific Northwest coast of North America from Cape Foulweather to the Bering Strait.
• James Rennell publishes a chart and memoir of the Agulhas Current, one of the first contributions to scientific oceanography.

  Medicine

• John Hunter publishes The Natural History of the Human Teeth.
• Samuel-Auguste Tissot begins publication of Traité des nerfs et de leurs maladies, including a classical account of migraine.
• Samuel Thomas von Sömmerring describes the organization of the cranial nerves.

  Technology

• Joseph Bramah patents an improved design of flush toilet in London.
• The brothers Hans Ulrich and Johannes Grubenmann complete a bridge across the Limmat at Wettingen in Switzerland, a 60 m span which is the first known use of a true arch in a timber bridge.

  Zoology

• Petrus Camper publishes On the Points of Similarity between the Human Species, Quadrupeds, Birds, and Fish; with Rules for Drawing, founded on this Similarity, an early work of comparative anatomy.
• Johan Christian Fabricius publishes his Philosophia Entomologica in Hamburg.

  Awards

• Copley Medal: Charles Hutton

  Births

• February 4 – A. P. de Candolle, Swiss botanist
• May 18 – Andrew Ure, Scottish industrial chemist and encyclopaedist
• December 6 – Joseph Louis Gay-Lussac, French chemist and physicist
• December 17 – Humphry Davy, English chemist
• December 25 – Joseph Aspdin, English inventor
• Maria Dalle Donne, Bolognese physician
• Anna Maria Walker, Scottish botanist

  Deaths

• January 10 – Carl Linnaeus, Swedish botanist, first to develop standard nomenclature for naming species
• February 20 – Laura Bassi, Italian scientist