DRAPER IN VIRGINIA

In January 1839 John William Draper held the position of professor of chemistry at Hampden Sydney College in Virginia. For most of the previous decade Draper had experimented with the chemical effects of light. In 1834-35 he published results of his earliest series of experiments in the Journal of the Franklin Institute of Philadelphia. For the next five years he was about the only person in America occupied with this subject. He published his work in the scientific journals of America and England.

In an 1858 letter Draper detailed the work he accomplished before Daguerre's and after Talbot's announcement:
For years before either Daguerre or Talbot had published any thing on the subject I had been in the habit of using sensitive paper for investigations of this kind. . . . When Mr. Talbots experiments appeared in the spring of 1839, they of course interested me greatly as having been at work on the action of light for so many years. I repeated what he published & varied it. This was whilst I was Prof at Hampden Sidney College in VA, and before anything had been published by Daguerre. I tried to shorten the long time then required for getting the picture of a house or a tree, by using lenses of larger aperture & short focus and this was the germ from which the art of portraiture eventually arose. . . . I could get images of any brightly illuminated object, though too large and too faint. There was no difficulty in getting the outline of a part of a person standing against a window, but then it was of a silhouette and not a portrait, like those spoken of in Mr. Talbot's paper.

It was during my repetitions of Mr. Talbot's exps that I recognized the practical value of the experiments I had made in 1835, and published in 1837 respecting the chemical focus of a non achromatic lens, and saw that the camera must be shortened to obtain a sharp picture. It is the exp of passing a cone of light through a known aperture on sensitive paper. It was from considering the difficulty of getting an impression from colored surfaces as red and green, that I saw the necessity of enlarging the aperture of the lens & diminishing its focus, so as to have the image as bright as possible; for it was plain that in no other way could landscapes be taken or silhouettes replaced by portraits. And when I had failed altogether in these particulars, I knew it was owing to an insufficient sensitiveness in the Bromine paper, and waited anxiously for the divulging of Daguerre's process, respecting which statements were beginning to be made in the Newspapers.[13*]


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3. Draper, Morse, et. al., in New York


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1. Morse in Paris


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