It was named after Roswell Mason, an official of the Central Illinois Railroad.

Entity and relation annotations:
id: 0
type: entity
value: text: Roswell Mason
labels: <Person>
id: 1
type: entity
value: text: the Central Illinois Railroad
labels: <Organization>
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type: entity
value: text: Illinois
labels: <Location>
type: relation
to_id: 2
labels: Organization:located_in:Location
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type: relation
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labels: Person:affiliated_with:Organization
from_id: 0