The first photographic negative was made around 1824 by William Henry Fox Talbot, a British amateur scientist. He coated paper with a light-sensitive silver solution and placed it in a camera obscura. The areas exposed to the most light became dark, while the shadowed areas remained pale. He ■fixed■ the paper with a solution that washed away the unexposed silver and left a reversed, or negative, image of the view that appeared in the camera obscura. When Talbot placed this negative image against a second piece of sensitized paper and exposed it to light, he made a new, positive image, which he called a ■calotype,■ from ■kalo,■ the Greek word for beauty, and ■typus,■ the Latin word for image.
The paper negative produced a blurry, soft positive because it transmitted both the image and texture of the paper on which it was made. Over the next thirty years, inventors searched for a way to attach a light-sensitive coating to glass, so that they could create a transparent negative without distortion. Finally, in 1851 Frederick Scott Archer solved the problem, and photographers were able to use glass negatives to print images on paper.
2. Jefferson Davis /Mathew Brady Studio/Carte-de-visite