Fisk Holbrook Day

Who was Fisk Holbrook Day?

Fisk Holbrook Day was a physician and an amateur geologist in Wisconsin who developed an impressive collection of Silurian-age fossils. The collection is now at Harvard University.

Day was born on March 11, 1826 in Richmond, New York. He graduated from Jefferson Medical College in Philadelphia, Pennsylvania in 1849. He moved to Wauwatosa, Wisconsin and lived there for 40 years, "and at one time was considered its most prominent citizen." He became the first physician to serve as Superintendent of the Milwaukee County hospital and led in many reforms for the hospital and for a system of county insane asylums throughout Wisconsin.

He once could sell a trilobite for "the then-extravagant sum of $100". The fossil trilobite was named Bumastus dayi in honor of Day.

One of the primary places he collected was at the Schoonmaker Quarry, which professional geologist/paleontologist James Hall had recognized in 1862 as the first known fossil reef in North America. "Day supplied specimens and information to other professional geologists, including Fielding Bradford Meek, Charles Doolittle Walcott, E.O. Ulrich, Samuel Colvin, Edward Drinker Cope, A. W. Vogdes, Nathan Shaler and Thomas C. Chamberlin. In addition to his interactions with professional scientists, Day corresponded and exchanged specimens with amateur naturalists around the country."