About: http://webisa.webdatacommons.org/9145132

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	Apparatus according to claim 1, including circuit means for causing the measure of the distance obtained to be observable permanently on the screen of the cathodic oscillograph. 4.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com