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Dudley, Robert

1. Dates
Born: Sheen House, Surrey, 7 Aug. 1573
Died: Florence, Italy, 6 Sept. 1649
Dateinfo: Dates Certain
Lifespan: 76
2. Father
Occupation: Aristocrat
Robert Dudley, Earl of Leicester.
It is dubious that our Robert Dudley was legitimate, although his father was very fond of him and certainly reared him as his heir.
3. Nationality
Birth: English
Career: English, It
Death: It
4. Education
Schooling: Oxford
Oxford University, Christ Church, 1588-c.90.
Dudley, to whom a degree had no significance, did not earn a B.A.
5. Religion
Affiliation: Anglican, Catholic
When he left England, Dudley converted to Catholicism.
6. Scientific Disciplines
Primary: Navigation, Cartography
Dudley's Dell'arcano del mare, 1646-7, was a major work on navigation and cartography. It contained an appendix (made into a preface in the second edition) "Delle scienze matematiche che entrano nell'opera dell'Arcano del mare."
7. Means of Support
Primary: Patronage
Secondary: Personal Means
He inherited the bulk of Leicester's estate, which included Kenilworth, 1589.
In 1594-5 Dudley commanded a privateering expedition, which appears to have been his personal undertaking, to the West Indies and the northern coast of South America. A year later, 1596, he served, as the commander of a vessel, in the expedition to Cadiz; he was knighted for his bravery here.
When he failed legally to establish his legitimacy in 1605, Dudley left England (abandoning his family and taking along a beautiful young woman, Elizabeth Southwell, whom he married bigamously). He embraced Catholicism, and settled in Florence under the protection of the Grand Duke. Obviously he sacrificed his considerable estate in England. Eventually he was able to salvage something by selling Kenilworth to Prince Henry, but only at a price well beneath its value.
He lived primarily on a pension from the Grand Duke, for whom he performed all sorts of services, mostly connected with his naval expertise. He also held the office of Grand Chamberlain to the Grand Duchess of Tuscany, 1606-1620s.
8. Patronage
Types: Court Official, Aristrocrat, Eccesiastic Official
Knighted by the Earls of Essex and Nottingham in 1596.
The Grand Duke of Tuscany (first Ferdinand I, then Cosimo II, and finally Ferdinand II) put him in charge of several engineering projects, granted him a pension said to have been of nearly L1000, and provided him with a country estate. The influence of the Grand Duke and Duchess with the Emperor (the Grand Duchess was his daughter) helped to secure Dudley's titles.
Apparently Leader's book (which I have not seen) prints an interesting letter of c. 1606 in which Dudley appealed to the Grand Duke for protection and told him about the services (of a naval sort) which he could render in return.
He dedicated the Arcano to the Grand Duke (Ferdinand II).
His assumed titles, Earl of Warwick and Duke of Northumberland, (to him, his justly inherited titles) were confirmed by the Holy Roman Emperor, Ferdinand II.
The Pope granted him a dispensation to marry Elizabeth Southwell (though he was legally married and the father of three daughters) and in 1630 entered him in the ranks of the Roman nobility.
9. Technological Involvement
Types: Navigation, Cartography, Civil Engineering, Architecture, Military Engineering, Hydraulics, Pharmacology, Instruments
Dudley should be seen as a practical man, able in mathematics, who entered into all of the technological activities that demanded mathematical expertise.
He published a large book on navigation, the Arcano del mare, based in the first place on his experience as a navigator at sea. He was also involved in shipbuilding, designing several new classes of warships.
Already on the expedition to the West Indies he prepared a map of Trinidad and of the coast of South America. Book 6 of his Arcano was on cartography, and it contained maps (charts for navigators) of the entire world. These maps are considered milestones in naval cartography. Dudley himself drew them up; they were not mere copies of the maps of others.
The Grand Duke put him in charge of building the port of Livorno. He designed the mole for its harbor.
Although I did not find references to specific buildings he had designed, contemporary descriptions of Dudley emphasized his skill in architecture. Wood says that the Grand Duke consulted him on all major buildings.
He functioned partly as a military engineer in Tuscany, and the Arcano contained a section on the fortification of ports.
He drained the swamp between Pisa and Livorno.
Dudley also developed a powder of supposedly (in the 17th century style) extraordinary medicinal power (but apparently used primarily as a purge), which made it into all the pharmacopaeias.
He was involved also with instruments. About 1598 he invented and made what he called an azimuth dial, essentially similar to Oughtred's horizontal instrument (and possibly copied from it, for Oughtred's manuscript was around at that time).
10. Scientific Societies
Memberships: None
Informal Connections: His report on the expedition to the West Indies was printed by Hakluyt, to whom he was distantly related. When he was young, he had a close association with Thomas Cavendish. He maintained a connection with his tutor Thomas Chaloner and his instructor Mathew Baker, master- shipwright. Note that with the possible exception of Hakluyt, these are generally practical men like Dudley himself.
  1. Dictionary of National Biography (repr., London: Oxford University Press, 1949-1950), 6, 122-4. Anthony à Wood, Athenae oxonienses (Fasti oxonienses is attached, with separate pagination, to the Athenae), 4 vols. (London, 1813-20), 3, 258-62. George F. Warner, "Preface," The Voyage of Robert Dudley . . . to the West Indies, 1594-1595, (London, 1899), i-lxvi.
  2. J.F. Schütte, "Japanese Cartography at the Court of Florence: Robert Dudley's Maps of Japan, 1606-1636," Imago mundi, 23 (1969), 29-58.
  3. Biographia Britannica, 2nd ed. (London, 1778-93), 5, 469-78.
  4. A.J. Turner, "William Oughtred, Richard Delamain and the Horizontral Instrument in Seventeenth Century England," Annali dell'Istituto e Museo di Storia della Scienze, Firenze, 6.2 (1981), 115.
Not Available and Not Consulted
  1. Vaughan Thomas, The Italian Biography of Sir Robert Dudley, (Oxford, 1861).
  2. J. Temple Leader, Life of Sir Robert Dudley, (Florence, 1895).
  3. Alberto Viviani, "Sir Robert Dudley, Duke of Northumberland, at the Grand Ducal Court," Florence, 12.4 (1961), 32-3.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

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©1995 Al Van Helden
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