Nicolas Louis Vauquelin, French chemist, 1820.
© Science Museum / Science & Society Picture Library
Lithograph by Julien Leopold Boilly of the French chemist Nicolas Louis Vauquelin (1763-1829). Vauquelin discovered Potasium dichromate in 1797 during the analysis of a mineral, which he later showed to contain a hitherto unknown metal. He named the element 'chromium'. He was also the first to isolate an amino acid - asparagine - obtained from asparagus. He became profesor of chemistry in Paris in 1809.