At the moment I am occupied by an investigation with Kirchoff which does not allow us to sleep. Kirchoff has made a totally unexpected discovery, inasmuch as he has found out the cause for the dark lines in the solar spectrum and can produce these lines artificially intensified both in the solar spectrum and in the continuous spectrum of a flame, their position being identical with that of Fraunhofer's lines. Hence the path is opened for the determination of the chemical composition of the Sun and the fixed stars.
Robert BunsenThe far northern scenery is absolutely desolate but is marvelously beautiful, and I shall never regret that I have seen it, even though it cost me the unbelievable privations and exertions which we suffer here.
Robert Bunsen