Portal:History of science/Selected anniversaries/July 31
- 1704 - Birth of Gabriel Cramer, Swiss mathematician (d. 1752)
- 1718 - Birth of John Canton, English physicist (d. 1772)
- 1726 - Death of Nicolaus II Bernoulli, Swiss mathematician (b. 1695)
- 1858 - Birth of Richard Dixon Oldham, British geologist (d. 1936)
- 1860 - Birth of Mary Vaux Walcott, American artist and naturalist (d. 1940)
- 1918 - Birth of Paul D. Boyer, American chemist, Nobel Prize Laureate
- 1919 - Birth of Primo Levi, Italian author and chemist (d. 1987)
- 1944 - Birth of Robert C. Merton, American mathematician
- 1964 - Ranger program: Ranger 7 sends back the first close-up photographs of the moon, with images 1,000 times clearer than anything ever seen from earth-bound telescopes
- 1980 - Death of Pascual Jordan, German physicist (b. 1902)