About: http://webisa.webdatacommons.org/352372995

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	To grind a concave curve into the mirror blank you place it on top, face down, grind with long strokes and have it hanging mostly off the side.
http://www.w3.org/ns/prov#wasQuotedFrom	slashdot.org