Researches in Spectrum-Analysis in Connexion with the Spectrum of the Sun I-II in Philosophical Transactions of the Royal Society of London 163 pp. 253-279 and 639-658, 1873 WITH Researches in Spectrum-Analysis in Connexion with the Spectrum of the Sun III-IV in Transactions of the Royal Society of London 164 pp. 479-494 and 805-813, 1874; WITH Researches in Spectrum-Analysis in Connexion with the Spectrum of the Sun, V in Philosophical Transactions of the Royal Society of London 172 pp. 561-576, 1881 [Sammelband of 5 Extracts [Parts I to V, complete]. 15 Plates]

London: Royal Society. 1st Edition. FIRST EDITIONS OF FIVE PAPERS (Parts I through V) BY LOCKYER DETAILING HIS SPECTRUM ANALYSIS OF THE SUN. Offered is a Sammelband (a book comprising a number of separately printed works that are subsequently bound together) of extracts in fine condition inside and out; in this case the extracts have been finely bound. The five papers include 13 large fold-out plates, including spectral photographs.

Sir Joseph Norman Lockyer (1836-1920) was an English scientist and astronomer. In the 1860s and while still an ‘amateur astronomist," Lockyer grew intrigued by the burgeoning field of electromagnetic spectroscopy - using the spectrograph as an analytical tool for determining the composition of celestial objects. He decided to apply his interest in the field to the study of the Sun.

In 1868 and after having adapted his 6-inch telescope to utilize a spectroscope, he was able to carry out electromagnetic spectroscopic observations of the sun during an eclipse. While doing so, he discovered a yellow line never seen before in the laboratory. Unable to reproduce the line in his lab, Lockyer made the bold suggestion that the line was the 'fingerprint' of an element, an element he named 'helium' for Helios, the Greek God of the Sun. Lockyer had discovered helium -- the only element to be discovered in space before it was discovered on Earth. Helium was the first element to be discovered by spectroscopy as well. Note that we offer this paper, the discovery of helium, separately.

Lockyer's "spectrum analysis in connection with the sun were numerous, original, and important" (The Astrophysical Journal, Vol. 53, 238). The papers included here span eight years and include the photographs of the metallic spectra in which he had "detected the difference between long and short lines, the thickening and thinning of lines with pressure, the variation in length, brightness, strength, and number of lines, and the change in general produced by variations in temperature" (ibid).

During these years and included here are Lockyer's photographic maps of the solar spectrum; his refractions maps, identification of the instruments used in creation as well as his method of mapping. He created diffraction maps as well, again detailing the instruments he used, how he determined wave-lengths and how he constructed his maps.

Lockyer's papers pay particular attention to his photographic method and process. Representation in spectral analysis was of obvious import and Lockyer, not always happy with the visibility of certain lines in photographs, so sometimes chose to provide both the conventional representation - drawings - alongside his enlarged photographs. Traditional hand-drawn spectral maps excel at some types of representation while photographic representation excels at others. Lockyer's inclusion of both in his research and in the papers included is advantageous in solar study because they supplement each other.

In 1869 Lockyer became a fellow of the Royal Society and in that same year, founded the influential (and still existent) scientific journal Nature. In 1885 he was appointed first professor of astronomy at the Royal College of Science. CONDITION & DETAILS: London: The Royal Society. 4to. 15 plates (most large fold-outs) as well as figures throughout. All five papers have been handsomely bound together in half calf over period appropriate marbled paper boards. The boards are gilt-ruled; the spine, gilt-lettered. The extracts themselves are bright and clean. Fine condition in every way.