From Nevil Maskelyne
ALS: American Philosophical Society
[Greenwich, December 11, 1769. The Astronomer Royal asks
Franklin, when he next writes to Philadelphia, to inquire of Owen
Biddle about the exact distances between the observation points for
the transit of Venus. Maskelyne cannot make Biddle’s two accounts
agree with each other, or with the distances given by Mason and Dixon
in their survey. He is also uncertain about the exact location of the
Norriton observatory in relation to the southernmost point of the
city of Philadelphia, and wants more exact data. The Pennsylvania
observers will likewise send him, he hopes, their observations on the
transit of Mercury on November 9, 1769, along with any other
observations that will help to establish the difference of
longitudes. He cannot, until his questions are answered, transmit
Biddle’s report to the Royal Society. He has transmitted the report
from John Winthrop that Franklin sent him, and also Winthrop’s
observation of the transit of Mercury in 1743, which had been read to
the Society but for some reason was not yet in print.]
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