_The Astronomical Evidence of the True Date of the Canterbury
Pilgrimage._
As a conclusion to my investigation of this subject, I wish to place
upon record the astronomical results on which I have relied in the
course of my observations; in order that their correctness may be open
to challenge, and that each reader may compare the actual phenomena,
rigidly ascertained with all the helps that modern science affords, with
the several approximations arrived at by Chaucer. And when it is
recollected that some at least of the facts recorded by him must have
been theoretical--incapable of the test of actual observation--it must
be admitted that his near approach to truth is remarkable: not the less
so that his ideas on some points were certainly erroneous; as, for
example, his adoption, in the _Treatise on the Astrolabe_, of Ptolemy's
determination of the obliquity of the ecliptic in preference to the more
correct value assigned to it by the Arabians of the middle ages.
Assuming that the true date intended by Chaucer was Saturday the 18th of
April, 1388, the following particulars of that day are those which have
reference to his description:--