Date | Text | |
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19 May 1869
Henry Horatio Dixon |
birth Henry Horatio Dixon Born 19 May 1869; died 20 Dec 1953 at age 84. Irish botanist who, with John Joly, investigated plant transpiration and originated the tension theory of sap ascent in trees (1894) building on the work of Eduard Strasburger, François Donny and Berthelot. Dixon's earlier work was in cytology and had developed sterile culture methods for seedlings (1892). After the 1894 publication, he made further transpiration experiments to consolidate his theory which he published in 1909 and 1914. He resolved the debate over the mechanism of xylem transport by proposing a compromise between the pulling power of the leaf and the tensile strength of the water columns. From 1910, he was curator of a new herbarium at Trinity College Dublin. |