Monday, February 10, 2020, 8:45 pm EST
Yale University
Monday, February 10, 2020, 8:30 pm EST
University of Pennsylvania
Saturday, February 8, 2020, 3:00 pm EST
Cold Spring Harbor Laboratory
Friday, February 7, 2020, 3:30 pm EST
Thursday, February 6, 2020, 6:30 pm EST
Wednesday, February 5, 2020, 7:00 pm EST
University of Toronto
Wednesday, February 5, 2020, 6:00 pm EST
Monday, February 3, 2020, 8:30 pm EST
University of Pennsylvania
Friday, January 31, 2020, 9:00 am EST
Friday, January 31, 2020, 12:00 am EST
University of Oklahoma
Philadelphia Central High School for Boys and Pennsylvania State Arsenal, 1839. This daguerreotype, created by Joseph Saxton, is the oldest known photograph taken in the United States. Image courtesy of the Historical Society of Pennsylvania.
© 2026 Consortium for History of Science, Technology and Medicine | Copyright Infringement