About: http://webisa.webdatacommons.org/29703851

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	In the 1960s, the USSR developed an experimental gun that could shoot streams of particles of a heavy metal such as tungsten or molybdenum at speeds of nearly 25 kilometers per second in air and over 60 kilometers per second in a vacuum.
http://www.w3.org/ns/prov#wasQuotedFrom	fas.org