Charles Mason
E116178
Charles Mason was an 18th-century English astronomer and surveyor best known for co-surveying the Mason–Dixon Line that defined part of the boundary between the American colonies.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Charles Mason canonical | 5 |
| Jeremiah Dixon | 3 |
How this entity was disambiguated
This entity first appeared as the object of triple T982595 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Charles Mason Context triple: [Mason–Dixon Line, namedAfter, Charles Mason]
-
A.
Henry Markham
Henry Markham was an American politician who served as the 18th governor of California from 1891 to 1895.
-
B.
Robert Bylot
Robert Bylot was a 17th-century English Arctic explorer and navigator known for his key role in early voyages searching for the Northwest Passage.
-
C.
John Mason
John Mason was a 17th-century English colonial military leader in New England, best known for his pivotal and controversial role in the Pequot War.
-
D.
John Cassin
John Cassin was a 19th-century American ornithologist known for describing numerous bird species and contributing significantly to early American bird taxonomy.
-
E.
Ernest W. Bowditch
Ernest W. Bowditch was a prominent American landscape architect of the late 19th and early 20th centuries known for designing grounds for major estates and public spaces in the United States.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Charles Mason Target entity description: Charles Mason was an 18th-century English astronomer and surveyor best known for co-surveying the Mason–Dixon Line that defined part of the boundary between the American colonies.
-
A.
Henry Markham
Henry Markham was an American politician who served as the 18th governor of California from 1891 to 1895.
-
B.
Robert Bylot
Robert Bylot was a 17th-century English Arctic explorer and navigator known for his key role in early voyages searching for the Northwest Passage.
-
C.
John Mason
John Mason was a 17th-century English colonial military leader in New England, best known for his pivotal and controversial role in the Pequot War.
-
D.
John Cassin
John Cassin was a 19th-century American ornithologist known for describing numerous bird species and contributing significantly to early American bird taxonomy.
-
E.
Ernest W. Bowditch
Ernest W. Bowditch was a prominent American landscape architect of the late 19th and early 20th centuries known for designing grounds for major estates and public spaces in the United States.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
British person
ⓘ
English person ⓘ astronomer ⓘ person ⓘ surveyor ⓘ |
| birthDate | 1728-04-25 ⓘ |
| birthPlace | Sapperton, Gloucestershire, England ⓘ |
| burialPlace |
Philadelphia
ⓘ
surface form:
Philadelphia, Pennsylvania
|
| citizenship | Kingdom of Great Britain ⓘ |
| commissionedBy |
Frederick Calvert, 6th Baron Baltimore
ⓘ
Thomas Penn ⓘ |
| coSurveyedWith | Jeremiah Dixon ⓘ |
| deathDate | 1786-10-25 ⓘ |
| deathPlace |
Philadelphia
ⓘ
surface form:
Philadelphia, Pennsylvania, United States
|
| employer |
Maryland proprietors
ⓘ
Pennsylvania proprietors ⓘ Royal Society ⓘ |
| endTimeOfMasonDixonSurvey | 1767 ⓘ |
| era | 18th century ⓘ |
| fieldOfWork |
astronomy
ⓘ
geodesy ⓘ land surveying ⓘ |
| gender | male ⓘ |
| hasWorkLocation |
British America
ⓘ
surface form:
British North America
Delaware Colony ⓘ Colony of Maryland ⓘ
surface form:
Maryland Colony
Colony of Pennsylvania ⓘ
surface form:
Pennsylvania Colony
West Virginia region ⓘ |
| helpedDefine |
boundary between Pennsylvania and Maryland
ⓘ
part of the boundary between the northern and southern American colonies ⓘ |
| influenced | subsequent U.S. state boundaries ⓘ |
| knownFor |
co-surveying the Mason–Dixon Line
ⓘ
measuring the boundary between the colonies of Pennsylvania and Maryland ⓘ work on longitude determination ⓘ |
| language | English ⓘ |
| legacy |
Mason–Dixon Line
ⓘ
surface form:
Mason–Dixon Line later associated with cultural boundary between U.S. North and South
|
| name | Charles Mason self-link ⓘ |
| nationality | English ⓘ |
| notableWork |
Mason–Dixon Line
ⓘ
surface form:
Mason–Dixon Line survey
|
| occupation |
astronomer
ⓘ
surveyor ⓘ |
| residence |
London, England
ⓘ
Philadelphia ⓘ
surface form:
Philadelphia, Pennsylvania
|
| startTimeOfMasonDixonSurvey | 1763 ⓘ |
| usedInstrument |
astronomical clock
ⓘ
transit telescope ⓘ zenith sector ⓘ |
| workedAt | Royal Observatory, Greenwich ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Charles Mason Description of subject: Charles Mason was an 18th-century English astronomer and surveyor best known for co-surveying the Mason–Dixon Line that defined part of the boundary between the American colonies.
Referenced by (8)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Jeremiah Dixon
this entity surface form:
Jeremiah Dixon
this entity surface form:
Jeremiah Dixon