1667 in science

Astronomy

• June 24 – The site of the Paris Observatory is located on the Paris Meridian.

Chemistry

• Johann Joachim Becher originates what will become known as phlogiston theory in his Physical Education.

History and philosophy of science

• Thomas Sprat publishes .

Mathematics

• James Gregory demonstrates the transcendence of π.

Physiology and medicine

• June 15 – Jean-Baptiste Denys performs the first blood transfusion from a lamb into a boy.
• Robert Hooke demonstrates that the alteration of the blood in the lungs is essential for respiration.
• Thomas Willis publishes Pathologicae Cerebri, et nervosi generis specimen.

Publications

• Nicolas Steno publishes Elementorum Myologiae Specimen, seu Musculi Descriptio Geometrica. Cui accedunt canis carchariae dissectum caput, et dissectus piscis ex canum genere in Florence, providing a foundation for the study of muscle mechanics, the ovary, and the sedimentary theory of geology.

Births

• April 29 – John Arbuthnot, Scottish-born polymath
• May 2 – Jacob Christoph Le Blon, German inventor of four-colour printing
• May 26 – Abraham de Moivre, French mathematician
• July 27 – Johann Bernoulli, Swiss mathematician

Deaths

• April 3 – Edward Somerset, 2nd Marquess of Worcester, English inventor
• April 10 – Jan Marek Marci, Bohemian physician
• June 5 – Grégoire de Saint-Vincent, Flemish mathematician probable date – Peter Mundy, English traveller