Robert Wilhelm Bunsen, German chemist and physicist, c 1870s.

Engraving of Bunsen (1811-1899) who pioneered spectrum analysis with Gustav Robert Kirchhoff (1824-1887). This led to the invention of the Bunsen-Kirchhoff spectroscope and the discovery of new elements. Bunsen himself discovered rubidium and caesium. He was a pioneer in photochemistry, invented the filter pump, and an actinometer with Sir Henry Roscoe (1833-1915). He did not invent the Bunsen burner, (probably devised by his technician), but improved its design. Toxic and flammable cacodyl compounds caused him to lose the sight of one eye and nearly die of arsenic poisoning, to which he discovered the antidote.