A worker works on the letter "R" with a reciprocating saw to cut up the letters for the "Carnegie Science Center" atop the Carnegie Science Center on the North Shore Monday. The letters are making way for expansion of the center at the construction site. (Photo by Darrell Sapp/Post-Gazette) #Pittsburgh #PGH #412 #CarnegieScienceCenter #NorthShore #NorthShorePGH #PGPhotos