Official websites use .gov A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
View of the rotunda from the mezzanine that includes researchers using the card catalog, offices on the mezzanine, a partial view of the mural, some of the card catalog, and shelves of reference works.
Copyright:
The National Library of Medicine believes this item to be in the public domain. (More information)