The year 1725 in science and technology involved some significant events.

Astronomy

James Bradley first observes stellar aberration.
John Flamsteed's Historia Coelestis Britannica is published posthumously in a version containing Flamsteed's revisions, thanks largely to the efforts of his widow, Margaret, and former assistants Abraham Sharp and Joseph Crosthwaite.

History of science

John Freind begins publication of The History of Physick, from the time of Galen to the beginning of the sixteenth century, chiefly with regard to practice, the first comprehensive history of medicine in English.

Mathematics

The binary numeral system is invented by Basile Bouchon.

Technology

Stereotype printing, a copying process, is developed by Scottish goldsmith William Ged. The concept later generates the word "stereotyping".
The ocular Harpsichord, or clavecin oculaire, comprising a 6-foot square frame above a normal harpsichord, is invented by the Jesuit mathematician and physicist Father Louis-Bertrand Castel. No illustrations of it remain.

Births

February 4 - Dru Drury, English entomologist (d. 1804)
May 23 - Robert Bakewell, English agriculturalist and geneticist (d. 1795)
September 16 - Nicolas Desmarest, French naturalist (d. 1815)
September 25 - Nicolas-Joseph Cugnot, French mechanical engineer (d. 1804)

Deaths