New and Improved

The Library of Congress is constantly in the process of improving its products and services to better assist its patrons, friends and researchers. Recently we launched a series of updates to the website, enabling users to find and use our online materials more easily. The Library’s main web search function has been improved. A new […]

The View From 30,000 … Maps!

This is a guest post by Donna Urschel of the Library’s Public Affairs Office. If you’ve ever wondered where you are, or where you might be going, know this: if you have access to a computer, the Library of Congress now has 30,000 maps online to guide you. In the basement level of the Library’s […]

Gateway to Knowledge Guest Post #7

This is the seventh in a series of guest posts by Abigail Van Gelder, who with her husband, Josh, is journeying across the country on the Library’s “Gateway to Knowledge” traveling exhibition: We knew that Oberlin, OH was going to be a special event.  Oberlin College is the alma mater of Emily Rapoport—who, with her […]

Gateway to Knowledge Guest Post #5.1

This is one of a series of guest posts by Abigail Van Gelder, who with her husband, Josh, is journeying across the country on the Library’s “Gateway to Knowledge” traveling exhibition: Congressman Charlie Wilson from Ohio stopped by to welcome guests to the Gateway To Knowledge exhibit on its first day in Marietta; he was joined […]

New Optical Lab Brings LOC into 21st Century

(The following is a guest article about new preservation capabilities at the LOC by my colleague Donna Urschel, which was recently published in the the Library’s staff newsletter, the Gazette.)

Library of Congress Optical Properties Lab

Preservation Research Chief Eric Hansen explains how equipment is used to capture sound from damaged audio recordings. (Abby Brack photo)

For many decades, details of the 1791 Pierre L’Enfant Plan of Washington, D.C.—one of the many treasures at the Library of Congress—had been obscured. A long-ago application of a varnish preservative had darkened the map’s surface. But today, thanks to special imaging techniques, the invisible streets and special locations, including the “President’s House” and “Congress’ House,” pop out.

Hyperspectral imaging, a process of taking digital photos of an object using distinct portions of the light spectrum, is revealing what previously could not be seen by the human eye.

In room 27 on the sub-basement level of the James Madison Building, fascinating details of our historical heritage are coming to light in the recently opened Optical Properties Laboratory. Operated by the Library’s Preservation Research and Testing Division (PRTD) in the Preservation Directorate, the lab contains a hyperspectral imaging system, an environmental scanning electron microscope (ESEM), equipment for optical disc quality testing and a Fourier Transform Infrared Spectroscopy (FTIR) system.

The new lab enhances the Library’s capability to use nondestructive analytical techniques to track changes in optical properties of materials, helping conservators, curators and librarians extend the life of the collections. Along the way, many interesting details about the documents are revealed.

The Optical Properties Lab is one of three new labs in the Preservation Directorate. Two more will open in the Madison Building in 2010: the Chemical and Physical Properties laboratories. The new equipment and redesigned space will bring the 30-year-old science labs of the Preservation Directorate into the 21st century.

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Stephen Hobaica in the Library’s Preservation, Research and Testing lab tests for chemical markers of degradation of magnetic media. (Abby Brack photo)

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O Shenandoah, I Long to Map You

In a world where we can keep tabs on our own backyards from our desks at work, via satellite, it’s difficult to imagine the impact one man armed with notebooks and pencils could have in 1861 as the Civil War began to rend our young nation.  Generals on both sides of that conflict desperately needed good topographical information […]

Cartography Buffs, Take Note

Our very own John Hessler was featured in today’s Washington Post talking about some of the mysteries behind one of the grand-daddies of all maps, the 1507 Martin Waldseemüller World Map, the document that named “America” and one of the Library’s toppest of the top treasures. (OK, we don’t categorize the treasures quite that way, […]