Person: Auzout, Adrien
Adrien Auzout was a French astronomer who improved measuring instruments.
Mathematical Profile (Excerpt):
- Adrien Auzout Senior was an administrator in the Rouen law courts.
- He was able to study at the Jesuit College in Rouen and, although there is no record of Auzout knowing Blaise Pascal around 1640, both must have attended the Rouen Jesuit College at this time, so probably did know each other.
- Some sources claim that Auzout and Pascal collaborated after Pascal settled in Rouen in 1639.
- Certainly Auzout was present when Pascal gave public demonstrations in Rouen of variations on Torricelli's experiments inverting a column of mercury in a tube and observing the space above it which he correctly claimed must be a vacuum.
- It was not to be for Auzout had other ideas about his future.
- By these and perhaps other means Auzout evidently made enough money to survive in Paris, even if he was not necessarily a wealthy man.
- We do have a couple of pieces of information concerning people for whom Auzout undertook work.
- Auzout's interest in mathematics led to him arguing that a treatise on the quadrature of the circle was in error.
- By 1660 Auzout had become totally absorbed by his interest in astronomical instruments.
- This is of interest since the Observatory was established in 1667 as a result of the petition, and also since it suggests that Auzout was leading a group from Mersenne's circle who were seeking a formal status.
- Auzout produced a pamphlet concerning the orbit of the first of two comets of 1665, predicting an orbit for the comet based on about five observations he had made.
- The Royal Society in London decided to try to verify or disprove Auzout's predicted orbit by looking at observations of the comet made by others.
- Observations by Johannes Hevelius had led him to disagree with Auzout's predictions and a controversy between the two arose, particularly over one observation of the comet by Hevelius on 18 February 1665.
- The importance of Auzout's work on comets is his belief that they followed regular orbits and were thus permanent members of the solar system.
- By the summer of 1666 Auzout and Picard were making systematic observations with fully developed micrometers.
- In a letter sent on 28 December 1666 to Henry Oldenburg, the first secretary of the Royal Society of London, Auzout explained how his new micrometer, with two parallel wires either of silk of silver, one of which could be moved by a screw, could be used to calculate the diameters of the planets and the parallax of the moon.
- Auzout was not the first to invent a micrometer but it is his design which has become the basis of the modern instrument.
- In 1666 Auzout was one of a group of scientists making astronomical observations from Jean-Baptiste Colbert's Paris residence.
- In addition to Auzout the others involved were Christiaan Huygens, Pierre de Carcavi, Gilles de Roberval, Bernard Frénicle de Bessy and Jacques Buot.
- Auzout was one of these founding members and he quickly made a contribution.
- This was the first known proposal for a scientific expedition and Auzout presented it to the Academy only three weeks after its first formal meeting.
- Auzout, despite being one of the most vigorous in pushing for the opening of the Academy, was already showing frustration that things were not going as he had hoped.
- In 1668 Auzout resigned from the Académie des Sciences and left France.
- Auzout had studied Vitruvius throughout most of his life and was fascinated by Roman architecture.
- Auzout did not completely cut himself off from his previous life, however, for when William Petty claimed that London was greater than Paris and Rouen combined, quoting population statistics to prove his case, Auzout responded vigorously in November 1686.
- The Petty-Auzout controversy continued for some time.
Born 28 January 1622, Rouen, France. Died 23 May 1691, Rome (now Italy).
View full biography at MacTutor
Tags relevant for this person:
Astronomy
Thank you to the contributors under CC BY-SA 4.0! 
- Github:
-
- non-Github:
- @J-J-O'Connor
- @E-F-Robertson
References
Adapted from other CC BY-SA 4.0 Sources:
- O’Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive
