This image was acquired from
flickr. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
landscape outdoor pittsburgh monochrome blackandwhite architecture black and white . ampquotDr. Walter F. Rittman. Gasoline plant at Pittsburg.ampquot Bureau of Mines chemical engineer Walter Rittman developed the ampquotRittman processampquot used in petroleum refining. . quotDr. Walter F. Rittman. Gasoline plant at Pittsburg.quot