Friedrich Parrot

Johann Jacob Friedrich Wilhelm Parrot (14 October 1791 – 15 January 1841) was a Baltic German naturalist and traveller, who lived and worked in what was then the Governorate of Livonia, a part of the Russian Empire.

Born in Karlsruhe, in the Margraviate of Baden, Parrot was the son of Georg Friedrich Parrot. He studied medicine and natural science at the University of Dorpat in present-day Estonia and, in 1811, undertook an expedition to the Crimea and the Caucasus with Moritz von Engelhardt. There he used a barometer to measure the difference in sea level between the Caspian Sea and Black Sea.

On his return he was appointed assistant doctor and, in 1815, surgeon in the Russian army. In 1816 and 1817, he visited the Alps and Pyrenees. In 1821, he was professor of physiology and pathology, then in 1826 professor of physics at the University of Dorpat, and in 1828 Parrot undertook another voyage to Kakheti and Armenia. In 1837 he went to Tornio in northern Finland to observe oscillations of a pendulum and terrestrial magnetism. He invented a gasometer and a baro-thermometer. In Livonia, he popularised the Catalonian sundial, a small, cylindrical, pocket-sized instrument, approximately 8 cm in length and 1.5 cm in diameter.

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