I wished to find out whether a similar bright line could be seen in the spectrum of sunlight as in the spectrum of lamplight, and I found, with the telescope, instead of this, an almost countless number of strong and feeble vertical lines which, however, were darker than the other parts of the spectrum, some appearing to be almost perfectly black.

Joseph von Fraunhofer's Gesammelte Schriften (1888) p. 10, as quoted by Florian Cajori, A History of Physics in its Elementary Branches (1917)