About: http://webisa.webdatacommons.org/127827576

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	It was an intricate system, a craft, and like every other craft involved the mastery of certain tools, in this case such instruments as compass, hourglass, and quadrant.
http://www.w3.org/ns/prov#wasQuotedFrom	slideshare.net