About: http://webisa.webdatacommons.org/157081602

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Exhaust fumes, smoke and gases from autos, trains, steel mills, and other industries poured into the trapped air until they shut out the sun.
http://www.w3.org/ns/prov#wasQuotedFrom	yale.edu