About: http://webisa.webdatacommons.org/231495929

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	By means of suitable lenses 2 or other system the bubble is reflected and the position marking appropriately enlarged, e.g. 10 times, on an inclined plane or an inclined mirror 3 and focussing screen 4.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com