1699 in science

Biology

• English physician Edward Tyson publishes Orang-Outang, sive [Homo Sylvestris: or, the Anatomy of a Pygmie Compared with that of a Monkey, an Ape, and a Man], a pioneering work of comparative anatomy.

Exploration

• July 26 – William Dampier's expedition to New Holland (Australia) in HMS [Roebuck (1690)|HMS Roebuck] reaches Dirk Hartog Island at the mouth of what he calls Shark Bay in Western Australia and begins producing the first known detailed record of Australian flora and fauna.approx. date – Sir Isaac Newton develops a Octant (instrument)#Newton's [reflecting quadrant|reflecting quadrant].

Mathematics

• Abraham Sharp calculates π to 72 digits using an arctan sequence.

Paleontology

• Edward Lhuyd produces the first published scientific treatment of what would now be recognized as a dinosaur, describing and naming a sauropod tooth, "Rutellum implicatum" found at Caswell, near Witney, Oxfordshire, England.

Births

• March 23 – John Bartram, naturalist and explorer, "father of American botany"
• August 17 – Bernard de Jussieu, French botanist
• September 12 – John Martyn, English botanist

Deaths

• March 21 – Erhard Weigel, German mathematician and scientific populariser
• November 18 – Pierre Pomet, French pharmacist