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.
Exterior view showing several men removing a heavy concrete floor and riser from a two-wheeled trailer that was used for such transport to avoid personal injury and slab breakage.
Copyright:
The National Library of Medicine believes this item to be in the public domain. (More information)