William Herschel discovers first binary star, Xi Ursae Majoris.

Abraham Gottlob Werner asserts that all rocks have been deposited by a primordial ocean. This "Neptunian" view is accepted with little question.

Pierre François André Méchain discovers M80 (globular cluster in Scorpio).

Coloumb's Théorie des machiones simple (Theory of simple machines) is a study of friction.

Johan Carl Wilcke introduces the concept of SPECIFIC HEAT.

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The amateur British astronomer John Michell proposes the theoretical idea of an object massive enough that its gravity would prevent even light from escaping (which has since become known as a black hole). He realizes that such an object would not be directly visible, but could be identified by the motions of a companion star if it was part of a binary system. A similar idea was independently proposed by the Frenchman Pierre-Simon Laplace in 1795.

Horace-Bénédict de Saussure's Essais sur l'hygromé (Essay on measuring humidity) describes how to construct a hygrometer from human hair that can measure relative humidity.

Historian and naturalist Cosimo Alessandro Collini publishes a description of the first known pterosaur.

George Atwood accurately determines the acceleration of a free-falling body.

Charles Willson Peale establishes a natural history museum in Philadelphia, one of the first successful American museums.

Lazzaro Spallanzani performs artificial insemination on a dog.

In his Theory of the Earth, James Hutton explains the principle of uniformitarianism: all geological features can be explained by changes that can be observed now, taking place over very long periods of time.

Couloumb makes precise measurements of the forces of attraction and repulsion between charged bodies and between magnetic poles, using a torsion balance, demonstrating conclusively that electric charge and magnetism obey inverse-square laws like that of gravity. He also discovers that electrically charged bodies discharge spontaneously. In the 20th century, it is found that cosmic radiation is responsible for this discharge.

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Herschel discovers Enceladus, a moon of Saturn, and Titania and Oberon, moons of Uranus.

Jacques-Alexandre Charles shows that different gases expand by the same amount for a given rise in temperature (Charles Law).

Thomas Jefferson publishes Notes on the State of Virginia refuting Buffon's claim that America's harsh, moist climate stunts the growth of its inhabitants. He also addresses the issue of race, describing Native Americans favorably, but African slaves unfavorably.

Juan-Bautista Bru mounts the first relatively accurate fossil reconstruction of an extinct animal from South America. Georges Cuvier classifies it as a giant sloth.

Gilbert White's The Natural History and Antiquities of Selborne, a series of notes about animal and plant life in Selborne, England, is the first recognizable work of ecology. It goes through about 300 different editions and is still in print today.

Johann Wolfgang Goethe's Versuch, die Metamorphose der Pflanzen zu erklären (Attempt to explain the metamorphosis of plants) claims incorrectly that all plant structures are modified leaves, but clearly espouses evolution.

French polymath Antoine Lavoisier publishes a paper on French geology defining peacefully deposited pelagic sediments and violently deposited littoral sediments. He argues that these sediments illustrate a fluctuating sea level on an ancient planet.

The French chemist Antoine-Laurent de Lavoisier definitively states the Law of Conservation of Mass (although others had previously expressed similar ideas, including the ancient Greek Epicurus, the medieval Persian Nasir al-Din al-Tusi and the 18th Century scientists Mikhail Lomonosov, Joseph Black, Henry Cavendish and Jean Rey), and identifies (albeit slightly incorrectly) 23 elements which he claims can not be broken down into simpler substances.