About: http://webisa.webdatacommons.org/309644676

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	The improvements reside principally in a mechanism for adjusting the level of the chin rest in vertical direction and for securing the same by means of a screw device employing two threads of different pitch.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com