John Neagle art links 

John Neagle: Henry Clay, 1842
Photograph by Cliff, Creative Commons licensed

Art Institute of Chicago   NEW!
View of Peters' Island on the Schuylkill

Fine Arts Museums of San Francisco
3 works online (see works by "John B. Neagle")

John Neagle at the Metropolitan Museum of Art, New York City  
3 works by John Neagle online

Museum of Fine Arts, Boston  
Paintings collection online

John Neagle at the National Gallery of Art, Washington D.C.
6 works by John Neagle

Bowdoin College Museum of Art, Maine (Zoomable)
Portrait of Huizinger Messehert, ca.1822

Bowdoin College Museum of Art, Maine (Zoomable)
Portrait of Mrs. Huizinger Messehert, ca.1822

Brigham Young University Museum of Art, Utah

Brooklyn Museum, New York City   NEW!

Brooklyn Museum/Luce Center for American Art, New York City
(Undocumented Feature: In many cases the raw JPG image is much larger than displayed on the screen)

Canton Museum of Art, Ohio
Portrait Of H. Nofschert, Esq.

Cleveland Museum of Art, Ohio

Currier Gallery of Art, New Hampshire
Portrait of Captain Smith

Harvard University Art Museums, Massachusetts   NEW!

James A. Michener Art Museum, Doylestown, Pennsylvania
The Studious Artist (Thomas Birch), 1836

Pennsylvania Academy of the Fine Arts, Philadelphia

Princeton University Art Museum, New Jersey   NEW!

Westmoreland Museum of American Art, Greensburg, Pennsylvania
Mrs. Julia Wood

 
National Art Databases and Museum Inventories:

Smithsonian Institution Art Inventories
List of works nationwide from two sources: the Inventory of American Paintings Executed before 1914 and the Inventory of American Sculpture (only a few percent of listings have an accompanying image)

 

John Neagle in the Art Renewal Center

John Neagle at CGFA  

John Neagle at The Athenaeum  

Wikimedia Commons Image Database  

 

Grove Dictionary of Art Online (excerpt)  

Union List of Artist Names (Getty Museum)  
Reference sheet with basic information about the artist and pointers to other references.