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Published Version

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Rowan University Faculty Research Day 2023


David Kinnebrook is only known today as the assistant to the Astronomer Royal dismissed for marking stellar transits too slowly. Kinnebrook’s firing is commonly listed as the impetus for the personal equation as well as empirical psychology. Historians drawing their accounts from Nevil Maskelyne’s remarks on the dismissal, view Kinnebrook as a slightly misused, though mute, party in the affair. Kinnebrook’s letters, which resurfaced in 1985, present his side of the story. While scholars have discussed some aspects of the letters, they have not addressed Kinnebrook’s account of a months-long dispute with Maskelyne concerning observational disagreements. Kinnebrook’s letters provide an account of individual differences, observational practice, and Maskelyne’s failure to comprehend the problem. Had Maskelyne taken his assistant’s perspective seriously, the personal equation phenomenon might have been discovered 20 years earlier than it was.

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Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.