A photogenic drawing negative of Orchidea leaves.
After an extensive photographic experimentation, William Henry Fox Talbot created these studies. Though they are a bit splotchy and uneven in tone (due to an issue with unstable fix), they are the foundation on which Talbot perfected the first negative/positive photographic process: the calotype.
Leaves of Orchidea (and detail), April 1839, William Henry Fox Talbot. J. Paul Getty Museum.