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.
A man sitting at a desk with several books displayed; he is holding a feather duster and is wearing a fool's cap, as well as an oversized pair of spectacles.
Copyright:
The National Library of Medicine believes this item to be in the public domain. (More information)