The method originally used by Huggins, who first conceived and proved the possibility of measuring stellar velocities in the line of sight, was to measure with a filar micrometer the displacement of some well-known line in a stellar spectrum relative to the corresponding line of a terrestrial spectrum.
Thaler', Sir William Huggins and H.
Huggins, "The Astrolabe" (Astrophysical Journal, 1894); Penny Cyclopaedia, article "Astrolabe;" R.
SIR WILLIAM HUGGINS (1824-1910), English astronomer, was born in London on the 7th of February 1824, and was educated first at the City of London School and then under various private teachers.
In the last quarter of the 19th century spectroscopy and photography together worked a revolution in observational astronomy, and in both branches Huggins acted as pioneer.