[Elisa and John McAllister, children of W.Y. McAllister, Elisa standing on chair, John sitting in high chair]

The daguerreotype is a photographic process invented by the Parisian inventor and entrepreneur Louis Jacques Mandé Daguerre (1787-1851) who was the first person to publicly announce a successful method of capturing images. His invention was an immediate hit, and France was soon gripped by ‘daguerreotypomania’. Daguerre released his formula and anyone was free to use it without paying a license fee – except in Britain, where he had secured a patent. Daguerreotypes required a subject to remain still for several minutes to ensure that the image would not blur.

The Americana collection of Marian Sadtler Carson (1905-2004) spans the years 1656-1995 with the bulk of the material dating from 1700 to 1876. The collection includes more than 10,000 historical letters and manuscripts, broadsides, photographs, prints and drawings, books and pamphlets, maps, and printed ephemera from the colonial era through the 1876 centennial of the United States. It is believed to be the most extensive existing private collection of early Americana. The collection includes such important and diverse historical treasures as unpublished papers of Revolutionary War figures and the Continental Congress; letters of several American presidents, including Thomas Jefferson; a manuscript account of the departure of the first Pony Express rider from St. Joseph, Mo.; and what may be the earliest photograph of a human face. Many of the rare books and pamphlets in the collection pertain to the early Congresses of the United States, augmenting the Library's unparalleled collection of political pamphlets and imprints. The Carson Collection adds to the Library's holdings the first presidential campaign biography, John Beckley's Address to the people of the United States with an Epitome and vindication of the Public Life and Character of Thomas Jefferson, published in Philadelphia in 1800. The book was written to counter numerous attacks against Jefferson's character, which appeared in newspapers and pamphlets during the bitter election campaign. The Rare Book and Special Collections Division shares custodial responsibility for the collection with the Library's Geography and Map Division, Music Division, Prints and Photographs Division, and the Manuscript Division.

Langenheim Brothers was a photography studio founded in Philadelphia in 1846 by William and Frederick Langenheim. They were known for their innovative techniques and pioneering work in the field of photography. The Langenheim Brothers were among the first photographers to use the daguerreotype process and also experimented with stereoscopic photography, which produced 3D images. The Langenheim brothers' work was highly regarded and they received numerous awards for their photography, including a gold medal at the Great Exhibition in London in 1851. They also photographed notable figures of their time, such as Edgar Allan Poe and Abraham Lincoln. The Langenheim Brothers' studio continued to operate into the early 1900s, and their legacy lives on through their contributions to the development of photography as an art form.