I’ve recently stumbled upon the wonderful 1894 paper by non other than James Keeler entitled Spectroscopic Observations of Nebulae. Members who may have read The Day We Found the Universe by Marcia Bartusiak, and are interested in spectroscopy, will find it particularly entertaining. This was an age where we had not yet unravelled the true size of the universe (the mystery of the ‘spiral nebulae’) let alone atomic theory. In his paper, Keeler details the observational techniques and results of his ground breaking efforts at Lick Observatory in a wonderfully engaging dialogue. The Summary of Results at the end of the paper is particularly fascinating in light of the times.
Thanks for the reference to Huggins’ publication. His description of his equipment and his early visual spectroscopic observations is fascinating. His efforts to reliably calibrate his spectra are positively heroic. You get a real sense of his excitement in discovering the nature of the objects he was observing spectroscopically for the first time. He was one of the first to attempt to classify spectra in a systematic way. You can also sense his competitiveness in promoting his discoveries. It’s a great read.