<http://caligraph.org/ontology/Iron_bridge>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Metal_bridge> .
<http://caligraph.org/ontology/Iron_bridge_in_the_United_States>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Iron_bridge> .
<http://caligraph.org/ontology/Iron_bridge>	<http://www.w3.org/2000/01/rdf-schema#label>	"Iron bridge" .
<http://caligraph.org/ontology/Iron_bridge>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/2002/07/owl#Class> .
<http://caligraph.org/ontology/Wrought_iron_bridge>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Iron_bridge> .
<http://caligraph.org/ontology/Iron_bridge>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://en.wikipedia.org/wiki/Category:Iron_bridges> .
<http://caligraph.org/ontology/Cast-iron_arch_bridge>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Iron_bridge> .