Note 310 — Chapter XVIII · OBSERVATION.
Reading edition
See Notes to Measures of Double Stars, 1204, 1336, 1477, 1686, 1786, 1816, 1835, 1929, 2081, 2186, pp. 265, &c. See also Herschel’s Familiar Lectures on Scientific Subjects, p. 147, and Outlines of Astronomy, 7th ed. p. 285.