Jelle Zeilinga de Boer, the Harold T. Stearns Professor of Earth Science, emeritus, died July 23 at the age of 81. De Boer received his BS and PhD from the University of Utrecht before coming to Wesleyan as a postdoctoral fellow in 1963. During his early years at Wesleyan he worked closely with Geology Professor Jim Balsley in the field of paleomagnetism. In 1977, de Boer was named the George I. Seney Professor of Geology and in 1984 he was named the Harold T. Stearns Professor of Earth Sciences. In the 1970s de Boer worked as a joint professor at the…