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COLLECTION Identifier: gra00089

Botany Libraries daguerreotypes and ambrotypes

Scope and Contents

This collection is comprised of eleven daguerreotypes and three ambrotypes, circa 1840-1865. Most of the images are portraits of well-known botanists including Aimé Jacques Alexandre Bonpland, Edwin Faxon, Asa Gray, William Henry Harvey, Adrien Henri Laurent de Jussieu, François André Michaux, Thomas Nuttall, Charles Wilkins Short, John Torrey, Nathaniel Bagshaw Ward, and Sereno Watson. One daguerreotype depicts a Wedgwood medallion of Carl Linnaeus and another features C. A. Weatherby’s great grandparents the Atwoods.

The collection also includes two ambrotypes of diatoms, single-celled algae, by Amasa M. Eaton. The images were made by photomicrography, the photography of objects under a microscope.


  • circa 1840-1865

Conditions Governing Access

The collection is available by appointment for research. Researchers must register and provide one form of valid photo identification. Please contact for additional information.


1 collection (3 flat boxes (11 daguerreotypes in 10 cases and 3 ambrotypes))

Historical note - Daguerreotypes

The daguerreotype was the first successful form of photography. It was named for Louis-Jacques-Mandé Daguerre who discovered the process with Nicéphore Niépce in the 1830s. This form of photography was popular from the 1840s-1860s and consists of a positive image on a thin copper plate with a highly polished, mirrorlike coating of silver. Daguerreotypes were often placed in small cases with a glass covering to protect the image.

Resources: The Editors of Encyclopaedia Britannica. 2019. Encyclopaedia Britannica. Daguerreotype. ( Accessed 2020 March 27.

Reilly, J., McCabe, C., & Eastman Kodak Company. 1986. Care and identification of 19th-century photographic prints (Kodak publication ; no. G-2S). Rochester, N.Y.: Eastman Kodak.

Historical Note - Ambrotypes

The ambrotype process was patented in 1854 and its heyday was the mid-1850s to mid-1860s. Ambrotypes were similar to daguerreotypes but were less expensive and faster to produce. They consist of an underexposed glass negative placed against a dark background to create a positive image and were often sold in decorative frames or cases.


Library of Congress. Ambrotypes and Tintypes. Website ( Accessed 2020 May 1.

Arrangement Note

The daguerreotypes and ambrotypes are housed in individual custom boxes which are stored in three flat boxes

Custodial History

All of the daguereotypes and the Thomas Nuttall ambrotype are part of the Archives of the Gray Herbarium.

The Amasa Eaton ambrotypes of diatoms are part of the Archives of the Farlow Herbarium of Cryptogamic Botany, Harvard University.


The items in this collection are from various sources. Several of the daguerreotype portraits belonged to Asa Gray. The Anson Seth Atwood & Sarah Palmer Atwood portrait was originally from the C.A. Weatherby papers. The Edwin Faxon portrait was given to the Gray Herbarium by Mr. W. Faxon August 6, 1918. The provenance of several items is unknown.

Related Resources for Amasa Eaton's Ambrotypes of Diatoms

Barrar. W. (2016 spring) Rare Early Diatom Ambrotype Photographs by Amasa Mason Eaton (1841-1914). Newsletter of the Friends of the Farlow. Accessed 2020 May 1 May.

Eaton, Amasa M. Micro-photography, or the photgraphic delineation of microscopic objects. Proceedings of the Boston Society of Natural History Vol. viii, 1862:105-7. Accessed 2020 May 1.

Related Materials

Related materials as Harvard:

Daguerreotypes at Harvard

Daguerreotype Conservation and Digitization Note

In 1995, the Harvard University Library received a grant from the National Historical Publications and Records Commission to preserve and enhance access to Harvard’s daguerreotypes.

The daguerreotypes in this collection were part of that project. The daguerreotypes underwent a conservation review, were individually cataloged, and digitized.

Ambrotype Conservation and Digitization Note

In 2015, the Amasa Eaton ambrotypes of diatoms underwent a conservation review and were cleaned and rehoused.

None of the ambrotypes in this collection are digitized.

Botany Libraries daguerreotypes and ambrotypes, circa 1840-1865: A Guide.
Botany Libraries, Gray Herbarium Library, Harvard University.
2020 July
Description rules
Language of description

Repository Details

Part of the Botany Libraries, Gray Herbarium Library, Harvard University Repository

The Harvard University Herbaria houses five research libraries that are managed collectively as the Botany Libraries. The Gray Herbarium Library specializes in the identification and classification of New World plants with emphasis on North American plants. The Archives of the Gray Herbarium houses unique resources including personal papers, institutional records, field notes and plant lists, expedition records, photographs, original artwork, and objects from faculty, curators, staff, and affiliates of the Gray Herbarium.

Harvard University Herbaria
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