1715 in science

Astronomy

• May 3 – Total solar eclipse across southern England, Sweden and Finland.
• Edmond Halley suggests that nebulae are clouds of interstellar gas.
• Publication in London of David Gregory's The elements of astronomy, physical and geometrical... Done into English, containing the first recorded use in English of the word Physics in its modern scientific sense and the first mention of a series approximating the Titius–Bode law on celestial orbits.

Discoveries

• Mine La Motte, in Madison county, Missouri, is discovered by De la Motte Cadillac.
• The "miracle" springs are discovered in Cheltenham, England, a small Cotswold village at the time.

Geology

• Edmund Halley suggests using the salinity and evaporation of salt lakes to determine the age of the Earth.

Mathematics

• Brook Taylor's Methodus Incrementorum Directa et Inversa adds a new branch to the higher mathematics, now designated the "calculus of finite differences", and introduces Taylor's theorem and the Taylor series.
• Taylor also publishes his Essay on Linear Perspective, which discusses the principles of perspective and the vanishing point.

Medicine

• French anatomist Raymond Vieussens's Traité nouveau de la structure et des causes du mouvement naturel du coeur is published in Toulouse, giving the first description of valvular disease of the heart.

Technology

• The first recognised fire extinguisher is invented.
• Construction of Brod Fortress by the Arduchy of Austria begins.approx. date – In clockmaking, George Graham invents his deadbeat escapement and experiments with compensation pendulums.

Births

• April 3 – William Watson, English physician, botanist and physicist
• September 22 – Jean-Étienne Guettard, French physician and scientist
• October 8 – Michel Benoist, French Jesuit missionary and scientist
• November 13 – Dorothea Erxleben, German physician
• November 23 – Pierre Charles Le Monnier, French astronomer

Deaths

• January 29 – Bernard Lamy, French mathematician, philosopher and physicist
• February 17 – Antoine Galland, French archaeologist
• March – William Dampier, English explorer, hydrographic surveyor and triple circumnavigator
• May – Thomas Savery, English engineer, inventor of a steam pump
• May 21 – Pierre Magnol, French botanist
• June 19 – Nicolas Lémery, French pharmacist and chemist
• August 16 – Raymond Vieussens, French anatomist
• September 24 – Wilhelm Homberg, Dutch chemist working in France
• October 15 – Humphry Ditton, English mathematician
• November 1 – Shibukawa Shunkai, Japanese scholar and astronomer