Princeton professor of Natural Philosophy, and later first Secretary of the Smithsonian Institution, Joseph Henry relied on the daguerreotype process as a tool for his experiments with electrical induction and magnetism. John Buhler (Class of 1846) documented in his diary, My Microscope, that Henry had hired George Prosch to "take a daguerreotype of the Dark Lines of the Spectrum for old Prof." This daguerreotype portrait of Joseph Henry may date to 1843 as well, for Henry recorded in a letter to his wife of April 22, 1843 that he had his daguerreotype taken by Dr. Paul Beck Goddard in Philadelphia.

The white marks that look like curtains along each side of the image may be examples of defective silvering on the plate or improperly applied sensitizing chemicals.

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