Anna Atkins, 1854 (ca), Adiantum Capillus Venerum, Museum Ludwig, LL/7716

Anna Atkins, 1854, Polypodium crenatum, Norway, Cyanotype, 32.9 x 23.6 cm, National Gallery of Canada / Musée des beaux-arts du Canada, Courtesy of the National Gallery of Canada (no. 19712), Purchased 1983, LL/6712

Thomas Eakins, 1890-1892 (ca), Standing Nude (Samuel Murray), Cyanotype, 4 3/8 x 3 11/16 in (11.1 x 9.3 cm), Smithsonian Hirshhorn Museum and Sculpture Garden, Gift of Joseph H. Hirshhorn, 1966, Accession Number: 83.108, LL/37582

Unidentified photographer, 1899, Dewey Day, Montpelier, Vermont, Cyanotype, 9.75 in (24.76 cm) x 11 in (27.94 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #2420), LL/8912

Bertha Jaques, 1910 (ca), Dandelion Seeds, Taraxacium officinale, Cyanotype, photogram, 34.6 x 7.3 cm (13 5/8 x 2 7/8 in), American Art Museum, Smithsonian Institution, Museum purchase from the Charles Isaacs Collection made possible in part by the Luisita L. and Franz H. Denghausen Endowment, LL/7579

Bertha Jaques, 1910, Lavender, Lavendula labiatae, Cyanotype, photogram, 35.6 x 15.9 cm (14 x 6 1/4 in), American Art Museum, Smithsonian Institution, Museum purchase from the Charles Isaacs Collection made possible in part by the Luisita L. and Franz H. Denghausen Endowment, LL/7580

Bertha Jaques, 1910 (ca), Milkweed Pods, Asclepias cornuti, Cyanotype, photogram, 32.4 x 20.3 cm (12 3/4 x 8 in), American Art Museum, Smithsonian Institution, Museum purchase from the Charles Isaacs Collection made possible in part by the Luisita L. and Franz H. Denghausen Endowment, LL/7581

Antoinette Putnam Cramer, 1905 (ca), Slender Gerardia (photogram), Cyanotype, 5 x 4 in (13x10 cm), Christopher Wahren Fine Photographs, Courtesy of Christopher Wahren Fine Photographs, LL/17466

Unidentified photographer, 1880s (ca), Study of Algae (Nitens), Cyanotype, 8.5 in (21.59 cm) x 6.5 in (16.51 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #2030), LL/8928

Unidentified photographer, 1890s, Amblysteglum, Cyanotype, 8.5 in (21.59 cm) x 6.5 in (16.51 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #1752), LL/8951

Unidentified photographer, 1910 (ca), Botanical Photogram, Cyanotype, photogram, 9.5 in (24.13 cm) x 3.75 in (9.52 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #2326), LL/8919

Lady Hatton [From her album], 1855 (ca), Hypolepis eepeny, Cyanotype, 33 x 20.4 cm, National Gallery of Canada / Musée des beaux-arts du Canada, Courtesy of the National Gallery of Canada (no. 39164), Purchased 1998 [Sometimes the work is falsely attributed to Lady Hatton but in reality they came from an album she owned.], LL/6711

Unidentified photographer, 1890, Vitraye (France), Cyanotype, 61 x 53.7 cm, AnamorFose, LL/10644

Unidentified photographer, 1890 (ca), Nottingham Sample Book #1 (UK), Cyanotype, 14.4 x 8.4 cm, AnamorFose, LL/10642

Unidentified photographer, 1890s, Lace maker's pattern with lace, Cyanotype, 10 x 9 in, Private collection of Brad Feuerhelm, LL/12982

Unidentified photographer, 1910, Photogram of a male torso (France), Cyanotype, 90.8 x 35.2 cm, AnamorFose, LL/10643

Unidentified photographer, 1890-1900, Rats, Cyanotype, Private collection of Steven Evans, LL/13095

Unidentified photographer, 1900 (ca), Saw Mill (exterior with two women), Cyanotype, 6.75 in (17.15 cm) x 4.5 in (11.43 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #1872), LL/8942

Unidentified photographer, 1900 (ca), Saw Mill (large cylinders, foreground), Cyanotype, 4.5 in (11.43 cm) x 6.75 in (17.15 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #1871), LL/8941

Unidentified photographer, 1900 (ca), Saw Mill (machinery and cylinders), Cyanotype, 4.5 in (11.43 cm) x 6.75 in (17.15 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #1870), LL/8944

Frances Benjamin Johnston, 1891, Breaker boys in Kohinor mine, Shenandoah City, Pa., Cyanotype, Library of Congress, Prints and Photographs Division, Reproduction Number: LC-USZC4-2322 (color film copy transparency) LC-USZ62-10106 (b&w film copy neg.), LL/37120

Unidentified photographer, 1910 (ca), Brick making [1 of 4], [Martin Lancaster, PA], Cyanotype, 10 x 8 ins, Private collection of Alan Griffiths, LL/9555

Unidentified photographer, 1910 (ca), Brick making [2 of 4], [Martin Lancaster, PA], Cyanotype, 10 x 8 ins, Private collection of Alan Griffiths, LL/9556

Unidentified photographer, 1910 (ca), Brick making [3 of 4], [Martin Lancaster, PA], Cyanotype, 10 x 8 ins, Private collection of Alan Griffiths, LL/9557

Unidentified photographer, 1910 (ca), Brick making [4 of 4], [Martin Lancaster, PA], Cyanotype, 10 x 8 ins, Private collection of Alan Griffiths, LL/9558

Unidentified photographer, 1880 (ca), CarriÞre, Normandie, Cyanotype, 22 x 28 cm, Photo Verdeau, LL/40001

Unidentified photographer, 1910 (ca), Goulds Manufacturing Co., Cyanotype, 9 in (22.86 cm) x 11 in (27.94 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #1738), LL/8948

Evelyn George Carey, 1887, 23 May - 1888, 10 May, Queensferry Cantilever As Seen From the South Approach Viaduct, Forth Bridge, Scotland, [Forth Bridge, Scotland], Cyanotype, CCA: Canadian Centre for Architecture, LL/44122

Unidentified photographer, 1890 (ca), Sunlit Interior, Cyanotype, 9.75 x 11.75 in (25x30 cm), Christopher Wahren Fine Photographs, Courtesy of Christopher Wahren Fine Photographs (gd43), LL/13025

Unidentified photographer, 1910 (ca), Woman in Canoe, Cyanotype, 4.5 in (11.43 cm) x 6.5 in (16.51 cm), Robert Tat Gallery, Courtesy of Robert Tat Fine Photographs (www.roberttat.com - #797), LL/8995

Unidentified photographer, 1900, A young girl standing on the deck of a sailing ship (America), Cyanotype, 20 x 14 cm, Dennis George Crow, Courtesy of Dennis George Crow (www.dennisgeorgecrow.com), LL/10711

Unidentified photographer, 1880-1890, French saling ship at sea (Off the Coast of Indochine), Cyanotype, 16 x 10.5 cm, Dennis George Crow, Courtesy of Dennis George Crow (www.dennisgeorgecrow.com), LL/10713

Charles F. Lummis, 1890 (ca), Mexican Soldiers on Horseback, Cyanotype, 5 x 8 in (127 x 203 mm), Charles Schwartz Ltd, Charles Schwartz Ltd. (#7009), LL/10820

Charles F. Lummis, 1900 (ca), Native Americans (probably Navaho) Gathered for Ritual, Southwest USA, Cyanotype, 4.5 x 7 in (114 x 178 mm), Charles Schwartz Ltd, Charles Schwartz Ltd. (#7355), LL/10819

Henri Le Secq, 1852 (ca), Farmyard scene, near St.-Leu-d' Esserent, Cyanotype, from paper negative, 21.7 x 32.2 cm, George Eastman Museum, Museum Purchase Museum purchase (GEH NEG: 5480, 81:1465:0007), LL/7436

Thomas Anshutz, 1880, Boys with a Boat, Ohio River, Near Wheeling, West Virginia, Cyanotype, 14.6 x 22.2 cm ( 5 3/4 x 8 3/4 in), American Art Museum, Smithsonian Institution, Museum purchase from the Charles Isaacs Collection made possible in part by the Luisita L. and Franz H. Denghausen Endowment, Object number: 1994.91.3, LL/7544

Unidentified photographer, 1915 (ca), Disadvantages of a Trestle, Cyanotype, 20.3 x 25.4 cm (8 x 10 in), American Art Museum, Smithsonian Institution, Museum purchase from the Charles Isaacs Collection made possible in part by the Luisita L. and Franz H. Denghausen Endowment, LL/7624

Unidentified photographer, 1895 (ca), View of a Stream with Figures, Cyanotype, 10.5 x 11.1 cm (4 1/8 x 4 3/8 in), American Art Museum, Smithsonian Institution, Museum purchase from the Charles Isaacs Collection made possible in part by the Luisita L. and Franz H. Denghausen Endowment, LL/7643

Henry P. Bosse, 1885, U.S. Towboat "Alert" #159, [Views on the Mississippi River], Cyanotype, 10 1/4 x 13 in, Lee Gallery, LL/12431

R. Salleron, 1889, 25 August, Bassin ua grand Trianon, Cyanotype, 6.75 x 9 in (17 x 23 cm), Christopher Wahren Fine Photographs, LL/20008

R. Salleron, 1890 (ca), Ornamental Wall, Cyanotype, 9 x 6.75 in (23 x 17 cm), Christopher Wahren Fine Photographs, LL/20009

Unidentified photographer, 1880 (ca), Boulevard de Belleville, Paris, Cyanotype, 12 x 15.5 cm, Photo Verdeau, LL/40035

J. Couyat, 1911, Egyptian Grafitti, Cyanotype, 4.5 x 5.5 in (14 x 12 cm), Christopher Wahren Fine Photographs, LL/19967

Unidentified photographer, 1875-1889, Photograph of Mount Jackson, Fusilade Mountain, and Mount Reynolds., Cyanotype, National Archives and Records Administration, [ARC Identifier: 282362], LL/6609

Arthur Wesley Dow, 1900 (ca), Landscape, Cyanotype, 4 3/4 x 6 3/4, Lee Gallery, (W1024), LL/13372

Arthur Wesley Dow, 1900 (ca), Landscape, Cyanotype, 4 5/8 x 6 3/4, Lee Gallery, (W1025), LL/13373

Unidentified photographer, 1900 (ca), Beach at Arcachon, Cyanotype, 5 x 7 in (12x18 cm), Christopher Wahren Fine Photographs, Courtesy of Christopher Wahren Fine Photographs (ia678), LL/13010

Unidentified photographer, 1892 (ca), Nevada Falls, Yosemite, Cyanotype, 6.5 x 4.5 in (17x11 cm), Christopher Wahren Fine Photographs, Courtesy of Christopher Wahren Fine Photographs (ha97), LL/13009

Charles Ripley (1842-1887), 1880 (ca), Pemambuco, Brazil, Cyanotype, 5 15/16 x 8 in, Peabody Essex Museum, LL/39763

Irving Underhill, 1900 (ca), Montage of New York scenes on fabric, Cyanotype, on fabric, 17 x 17 in (43.2 x 43.2 cm), Swann Galleries - New York, Courtesy of Swann Galleries (Auction, Dec 7, 2006, #2097, Lot 384), LL/15997

Unidentified photographer, 1899 (ca), [Our bedroom in our flat on 116th Street.], Cyanotype, Museum of the City of New York, X2010.11.5770, LL/52028

Unidentified photographer, 1910 (ca), Pierrot (Belgium), Cyanotype, 39.4 x 29 cm, AnamorFose, LL/10641

Unknown (English), 1900, Portrait with additions, Cyanotype, clichi-verre, Private collection of Brad Feuerhelm, LL/20430

Paul Burty Haviland, 1905 (ca), Untitled, Woman with Fan, Cyanotype, Lee Gallery, Image courtesy of the Lee Gallery (www.leegallery.com), LL/20405

Frances Benjamin Johnston, 1885-1900, Man posed on rocks, nude, playing pipe (Pan), Cyanotype, Library of Congress, Prints and Photographs Division, LC-DIG-ppmsc-04880 (digital file from original), LL/37113

Unknown (United States), 1900 (ca), Untitled, Ostriches, Cyanotype, 3 3/8 x 3 3/8 in (8.5 x 8.5 cm), KaufmaNelson Vintage Photographs, LL/24938

Unidentified photographer, 1915, Man sleeping on a canon (Homme dormant sur un canon), Cyanotype, 8.5 x 11 cm, Vintage-Photos, LL/32619

Unidentified photographer, 1895 (ca), A little girl sitting on a bench outdoors with her doll, Cyanotype, 4 1/2 x 3 1/2 in, J. Cosmas Vintage Photography, LL/32650

Frances Benjamin Johnston, 1899 (ca), Girls in bloomers on climbing apparatus, Western High School, Washington, D.C., Cyanotype, Library of Congress, Prints and Photographs Division, Reproduction Number: LC-USZC4-2047 (color film copy transparency) LC-USZ62-65804 (b&w film copy neg.), LL/37124

Frances Benjamin Johnston, 1900 (ca), Interior of Frances Benjamin Johnston's studio at 1332 V St. NW, Washington, D.C., showing a large camera and props arranged for a portrait, Cyanotype, Library of Congress, Prints and Photographs Division, Reproduction Number: LC-DIG-ppmsc-04831 (digital file from original) LC-USZ62-83155 (b&w film copy neg.), LL/37110

Unidentified photographer, n.d., A lady and gentleman on a river bank, Cyanotype, stereo, Private collection of Gary Dineen, LL/39558