1745 in science

Astronomy

• The Omega Nebula, Messier 25, Messier 35, and IC 4665 are discovered by Philippe Loys de Chéseaux.

  Biology

• Charles Bonnet publishes his first work on entomology, entitled Traité d'insectologie.

  Geography

• The Cassini projection, a type of map projection, is described by César-François Cassini de Thury.

  Medicine

• May 2 – The Company of Surgeons separates from the Company of Barbers of London.
• The Dublin Lying-In Hospital is established by Bartholomew Mosse.

  Physics

• The Leyden jar, a device for storing electric charge, is invented by Pieter van Musschenbroek. It Is the first capacitor.
• Ruđer Bošković publishes De Viribus Vivis in which he tries to find a middle way between Newton's gravitational theory and Leibniz's monadology, developing a concept of "impenetrability" as a property of hard bodies which explains their behavior in terms of force rather than matter.

  Technology

• The first blasting cap, or detonator, is demonstrated by a Dr. Watson of the Royal Society.

  Awards

• Copley Medal: William Watson

  Births

• January 6 – Jacques Étienne Montgolfier, French inventor
• January 7 – Johan Christian Fabricius, Danish entomologist
• January 23 – William Jessop, English civil engineer
• February 18 – Alessandro Volta, Italian physicist and chemist
• April 20 – Philippe Pinel, French psychiatrist
• April 26 – Johann Anton Güldenstädt, German naturalist and explorer
• November 30 – Jean-Louis Baudelocque, French obstetrician
• December 15 – Johann Gottfried Koehler, German astronomer
• December 28 – Juan de Ayala, Spanish explorer
• William Cruikshank, Scottish-born anatomist and chemist

  Deaths

• November 30 – Johann Bessler, German inventor