The green box in the periodic table represents the element thallium (Tl). Unfortunately, thallium was not discovered by my great-grandfather Ezra Thall but by British chemist/physicist William Crookes. At the tender age of 25, Crookes inherited a fortune from his father and proceeded to devote the rest of his life pursuing scientific research (Ezra would have pursued other interests).
When Crookes noted a bright green spectral line resulting from heating selenium minerals (1861), he realized the line represented a new element. Crookes called the element thallium from the Greek word "thallos" meaning green shoot (as in spouting grass). Looking for a Web site mascot, I chose the frog (green & jumps) and not grass!