1751 in science

Astronomy

• The globular cluster 47 Tucanae, visible with the unaided eye from the southern hemisphere, is discovered by the French astronomer Nicolas Louis de Lacaille, who catalogues it in his list of southern nebulous objects: at a distance of 16000 lightyears, it has a total mass nearly 1 million times the Sun's mass and is 120 light years across, making it appear in the sky as wide as the full moon.

Biology

• Linnaeus publishes his Philosophia Botanica, the first textbook of descriptive systematic botanical taxonomy and the first appearance of his binomial nomenclature.

Chemistry

• Nickel is discovered, in the mineral nickeline, by chemist Axel Fredrik Cronstedt in Stockholm, Sweden.

Medicine and physiology

• May 11 – Pennsylvania Hospital founded in Philadelphia by Benjamin Franklin and Thomas Bond, the first in the United States.
• Newcastle Infirmary founded in Newcastle upon Tyne, England.
• The pupil reflex is discovered: it is the first reflex of the human body to be discovered.

Publications

• Commencement of publication in Paris of the Encyclopédie, ou dictionnaire raisonné des sciences, des arts et des métiers edited by Denis Diderot and Jean d'Alembert.
• 1st edition of Benjamin Franklin's Experiments and Observations on Electricity is published.

Awards

• Copley Medal: John Canton

Births

• April 5 – Maria Lullin, Swiss entomologist
• March 3 – Pierre Prévost, Swiss philosopher and physicist
• March 17 – Anders Dahl, Swedish botanist
• June 3 or 29 – William Roxburgh, Scottish surgeon and botanist, "father of Indian botany"
• July 1 – Antide Janvier, French precision clockmaker
• December 10 – George Shaw, English naturalist

Deaths

• June 9 – John Machin, English mathematician and astronomer
• August 22 – Andrew Gordon, Scottish-born Benedictine monk, physicist and inventor
• August 30 – Christopher Polhem, Swedish scientist and inventor
• November 30 – Jean-Philippe de Cheseaux, Swiss mathematician and astronomer