During the Civil War, cartographers invented new techniques to map the country and the conflict more accurately than ever before in the nation’s history. Since then, cartographic technology has evolved in ways never imagined, but many basic elements of mapmaking remain the same. The following is an article, written by Jacqueline V. Nolan and Edward […]
According to the 1860 census, the population of the United States that year was 31,429,891. Of that number, 3,952, 838 were reported as enslaved. The 1860 census was the last time the federal government took a count of the Southern slave population. In 1861, the United States Coast Survey issued two maps of slavery based […]
Just days stand between the book-lovers of the USA and the Library of Congress National Book Festival! But don’t just stare at the countdown clock on the Festival website … check out the speaking and book-signing schedules for our 125 authors, or listen to the podcasts already available from some of this year’s authors. That […]
Tonight the 2012 Olympics in London kick off. The excitement has certainly been building all year as enthusiasts have followed the torch relay and participating athletes and teams. I can admit that the games probably appeal to me for a few other different reasons than purely anticipating all the awesome competition. First, my favorite band, […]
If someone set a bowl of cheese curls in front of you and declared it “breakfast,” would you be able to discern it from cereal? Even if you’re the type who likes cold pizza at 7 a.m., odds are you would not be too quick to pour on the milk and dive in with a […]
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 […]
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 […]
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 […]
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 […]
(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.)
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.