Note 109 — Chapter CXXIII
P. Le Page (Peter Le Page) Renouf translation
“The amount of this motion by which the equinox travels backward, or retrogrades (as it is called), is per annum an extremely minute quantity, but which, by its continual accumulation from year to year, at last makes itself very palpable, and that in a way highly inconvenient to practical astronomers, by destroying, in the lapse of a moderate number of years, the arrangement of their catalogues of stars, and making it necessary to reconstruct them.” Herschel, Astronomy, chapter 4.