Baltimore Neighborhoods

The Passano Files*

Francis O’Neill standing in the main reading room with the Passano Historic Index File.

The most valuable resource for studying the buildings of Baltimore is not Google Maps—in fact, it isn’t online at all. It is an index card collection of historic structures known as the Passano File that lives in the H. Furlong Baldwin Library at the Maryland Historical Society. Edited and overseen by Francis O’Neill, a reference librarian who began working in the MdHS library in 1981(the year this writer was born), the file is comprised of over 40,000 entries.** If you walk into our library and hear the antiquated clacking of a typewriter, you are hearing the sound of Mr. O’Neill at work on the most richly detailed catalog of our city’s geographic history.Alongside Francis Scott Key’s Star Spangled Banner, the Paul Henderson Photograph Collection, the William Stone Engraving, and the McKeldin-Jackson Oral History Collection, the Passano File stands among the most valuable gems in our collection.

Eleanor Phillips Passano (1870-1949)

From 1935 through 1940, Eleanor Phillips Passano (1870-1949), a library volunteer at MdHS , worked on a card file that connected family names to specific properties in Baltimore and the surrounding counties. Over the course of the next 50 years, this file remained dormant. As the years passed, what was once a rich source of information became less and less useful; modern researchers had become chronologically detached from the family names previously associated with the buildings decades before.

By his fifteenth year at the MdHS library, O’Neill had noticed the waning use of the Passano File. More importantly, however, he recognized the informational value and research potential of the resource. In 1995 O’Neill began the process of reorganizing the Passano File according to geographical location rather than family name, linking the cards to a permanent physical space. Most importantly, he once again began updating and adding index cards, giving the Passano File a whole new life.

The Passano File is arranged geographically in the sense that it is alphabetical by street address. As you flip through the typed index cards, you physically travel east and west or north and south through Baltimore’s streets. Through address changes, fires, and demolitions, each index card describes the history of the buildings, estate, or neighborhoods that have existed at the modern address of the geographic space. Each card also contains further references to photographs, articles, and books about the structures.

Since the formal title is the Passano Historic Structures File, and structure is a somewhat vague term, O’Neill needed to settle on a definition. For convenience and practicality’s sake, O’Neill defines a structure as “anything you can go in and out of.”  Parks, neighborhoods, and cemeteries, accompany the buildings and city blocks. When asked how monuments fit into this scheme (being for the most part solid structures), he matter-of-factly responds, “I have a different file for those.”

As the majority of us get dumbfounded, overwhelmed, and are eventually numbed by the waves of information that constantly flow past us, Francis O’Neill narrows his scope. He casually filters, plucks, and types up information about the city as it changes around him. Luckily for those who venture into our library with a little curiosity, he makes it available for our use. I nominate a name change to the Passano-O’Neill File. Anyone with me?* The Passano File is open to researchers from 10-5pm Wednesdays through Saturdays. Ask for Mr. O’Neill.

As an example, I’ve photographed the cards for 2001-2003 Druid Park Drive from the file. You can see that these five cards contain detailed information about the location, as well as references to other books and articles in our library.

(Eben Dennis)

* The Passano File did indeed have its official name changed tothe Passano-O’Neill file on 4/20/13.

**index card count derived from a mathematical formula that relied heavily on the width of my finger.


18 Responses to “The Passano Files*”

  1. Reblogged this on Tuscany-Canterbury Architecture and commented:
    I wanted to pass on a wonderful resource that I just discovered at The Maryland Historical Society which is an invaluable resource for researching Baltimore architecture, The Passano Files.

    I just spent this past Saturday pouring over the cards and discovered great information about many buildings in my neighborhood. In addition, the files are so easy to use. I can’t wait to go back and dig some more!

    I hope that you enjoy this resource as much as I do. I can’t wait to go back and dig through the Passano files some more soon.

    Posted by tuscanycanterbury | 19. Oct, 2012, 12:47 am
  2. absolutely add O’Neill to the name. I could not handle all my research without these updated files. Francis is a treasure. Liz

    Posted by Elizabeth Nilson | 19. Oct, 2012, 12:03 pm


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  10. [...] I’m currently photographing looked like 50 to 100 years ago. I’m also planning on using the Passano-O’Neill file to research the individual histories of the properties I’m documenting. I plan to use this [...]

  11. [...] The Passano-O’Neill Files: Light Street (7-11); Mercer Street (106-110); Charles Street (231 North); Calvert Street (100-102 North) [...]

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  14. [...] stop curious moviegoers from inquiring about the dreaded book. Our wonderful reference librarian, Francis O’Neill,  fielded phone calls about the fictitious tome from all over the country and even from as far [...]

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