Thursday, April 2, 2020, 7:00 pm EDT
Johns Hopkins University
Thursday, April 2, 2020, 6:30 pm EDT
Tuesday, March 31, 2020, 6:00 pm EDT
Tuesday, March 31, 2020, 4:00 pm EDT
Johns Hopkins University
Monday, March 30, 2020, 8:30 pm EDT
Yale University
Monday, March 30, 2020, 7:30 pm EDT
University of Pennsylvania
Monday, March 30, 2020, 4:15 pm EDT
Harvard University
Sunday, March 29, 2020, 1:00 pm EDT
Cold Spring Harbor
Friday, March 27, 2020, 8:30 pm EDT
Johns Hopkins University
Friday, March 27, 2020, 9:00 am EDT
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.
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