Optics.
Franklin, Benjamin, 1706-1790. *#E145.2.3 A new and curious theory of light and heat; in a letter from B, Franklin to David Rittenhouse. (In American Philosophical Society. Transactions. Vol. 3, pp. 5-8. Philadelphia. 1793.)
This card was printed at the Boston Ss Public Library, July 17, 1920.
1.9503 — Optics. — Heat.