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Logan, James

1. Dates
Born: Lurgan, County Armagh, Ireland, 20 Oct. 1674
Died: Germantown, Pennsylvania, 31 Oct. 1751
Dateinfo: Dates Certain
Lifespan: 77
2. Father
Occupation: Cleric, Schoolmaster
Patrick Logan was a Scottish Anglican clergyman who became a Quaker and supported himself henceforth as a schoolmaster.
It is clear that the family was very poor.
3. Nationality
Birth: Irish (in the sense that he was born in Ireland. The family was part of the Scotch Irish community.)
Career: English. (I treat Pennsylvania as English.)
Death: English
4. Education
Schooling: No University
No university education.
5. Religion
Affiliation: Sect
Friends--classify as Sect.
6. Scientific Disciplines
Primary: Optics, Botany
Subordinate: Mathematics, Astronomy
Logan was one of the first men of science in the colonies. His isolation there, and his absorption in the governance of Pennsylvania, greatly limited his contributions to science. He was mathematically gifted and wholly self-educated in mathematics. Although he devoted considerable attention to the subject and attained some competence, he does not figure in the history of mathematics. So also he got his own telescope, observed the heavens, and composed a commentary on Halley's lunar tables.
In two areas he did enter the international discourse of science. He experimented on the generation of corn, a pioneer step toward hybridization. The work was published in the Philosophical Transactions and later separately in the Netherlands as Experimenta et meletemata de plantarum generatione, 1739. It was known to and cited by students of botany. He also simplied Huygens' method of finding the refraction of a lens (published in the Netherlands with the Experimenta as Canonum pro inveniendis refractionum, 1739), and he composed a paper on spherican aberration (Demonstrationes de radiorum lucis in superficies sphaericas, 1741).
7. Means of Support
Primary: Government, Estate Administration, Merchant
Secondary: Schoolmastering
Apprenticed to a linen draper in Dublin, 1687.
Assistant schoolmaster under his father in Bristol, 1690-3.
Schoolmaster in Bristol, 1693-7.
He set himself up in the linen trade, without much success, 1697-9.
Secretary, administrator, land agent, merchant of William Penn in Pennsylvania, 1699-1751. He received a rather poor salary of 100. (This could equally be called patronage.)
Most of his life in Pennsylvania he was a member of the provincial Council. He was Mayor of Philadelphia in 1722-3; Chief Justice of the Supreme Court of Pennsylvania 1731-9; Acting Governor, 1736-7. It is not clear in what I have read what remuneration these positions carried. As Clerk of the Council he received a small stipend, and I assume the other positions also paid.
Logan functioned as a merchant in his own right in Pennsylvania, and when he got down to it seriously, he made himself wealthy.
8. Patronage
Type: Gentry
William Penn.
9. Technological Involvement
Types: Mechanical Devices, Cartography
Invented Conestoga Wagon.
As Penn's agent Logan was charged with laying out tracts of land and running property lines, functions for which his mathematical skills eminently qualified him.
10. Scientific Societies
Memberships: None
Informal Connections: Close friendship with Thomas Godfrey: introduced higher mathematics to Godfrey, and defended his claim to invention of an improved mariner's quadrant in 1732.
Intimate friendship with John Bartram, botanist, like Godfrey, a Pennsylvanian.
Extensive correspondence with Robert Hunter, William Burnet, Cadwallader Colden, Josiah Martin, Johann Albrecht Fabricius, William Jones, Peter Collinson, some of them other colonials, some of them scientists/intellectuals in Europe.
Friendship with Flamsteed.
  1. Dictionary of National Biography (repr., London: Oxford University Press, 1949-1950), 12, 81-3. Frederick B. Tolles, James Logan and the Culture of Provincial America, (Boston, 1957). This is the definitive account of Logan.
  2. Frederick B. Tolles, "Philadelphia's first Scientist, James Logan", Isis, 47 (1956), 20-30.
  3. Frederick E. Brasch, "James Logan, a Colonial Mathematical Scholar," Proceedings of the American Philosophical Society, 86 (1943), 3-12.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

Note: the creators of the Galileo Project and this catalogue cannot answer email on geneological questions.

1995 Al Van Helden
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