www.loc.gov
According to the US Library of Congress website, it was, as was the House or Representatives:
The US Copyright Office is within the Library of Congress, which serves as its deposit library.
Molesey Library
The largest library in the America is the Library of Congress. This library is home to over 29,550,914 books and documents.
The FIDC (Federal Deposit Insurance Corporation) uses a gov extension in its website address because it is an agency that was created by the US Congress.
Thomas Jefferson sold his personal library to the U.S. Congress for $23,950 in 1815 to replace the collection at the Library of Congress after the library was burned down by the British in 1814.
All the necessary information is available at the US Copyright office website at http://www.copyright.gov.
Probably the British library with 25,000,000 books and over 150,000,000 items with the Library of congress with 30,000,000 books but only 125,000,000 items.
The web archive of the Library of Congress has collected about 385 terabytes of web archive data (as of January 2013).
The Congress called for the Constitutional Convention to address problems in governing the US.
Congress IS the legislative branch of US government. Library of Congress (LOC) Serves as the research arm of Congress and is recognized as the national library of the United States. Open to those above high school age without charge or special permission, it is the world's largest library and a resource to scholars and researchers.
The Library of Congress, which is the largest library in the world, uses the Library of Congress Classification System to classify and arrange it's books. This classification system, which was created by Herbert Putnam in 1897, is also used by most academic and research libraries both within and outside of the US.