J Clin Pathol 1981;34:287-291 Spectroscopy, colorimetry, and biological chemistry

SUMMARY The development of colorimetry and spectroscopy in the nineteenth century is described. An account is given of the application of their techniques to biological chemistry during that period. The development of the spectroscope in the nineteenth century On 19 November 1859, Carl von Steinheil recorded in his diary that Robert Bunsen and Gustav Kirchhoff had visited him in Munich to ask him to make for them a large apparatus to examine the 'fixed lines ' of the solar spectrum. ' It was only a matter of weeks (20 October) since they had an-nounced at the Royal Prussian Academy of Science in Berlin their new analytical technique which was to lead to the discovery of caesium in 1861 and of rubidium soon after. For Bunsen (1811-99), professor of chemistry at Heidelberg since 1852, 'spectru