Roland Duer Irving
Roland Duer Irving (April 27, 1847 – May 30, 1888) was an American geologist. He was born in New York city and graduated from Columbia College School of Mines in 1869 as a mining engineer. In 1879, he received his PhD, also from Columbia. Soon after his graduation he became assistant on the Ohio geological survey, and in 1870 was elected professor of geology, mining, and metallurgy at the University of Wisconsin. In 1879 the title of his chair was changed to that of geology and mineralogy. He became assistant state geologist of Wisconsin in 1878, and continued  as such until 1879. From 1880 to 1882 he was one of the United States census experts, and in 1882 was made geologist in charge of the Lake Superior division of the United States Geological Survey. His specialty was the micro-petrography of the fragmental rocks and crystalline schists, and pre-Cambrian stratigraphy and the genesis of some of the so-called crystalline rocks. He is considered one of the pioneers of petrography in the United States. He was the father of John Duer Irving, another noted geologist and editor of the journal "Economic Geology" from 1905 to 1918. Roland