See Hidden Doors (Wizard Spell)

This spell allows the savant to note secret or concealed doors within the area of effect. The surface of one wall up to 50 feet long can be scanned.
The material component is a polished glass lens through which the caster peers.
Notes: Restricted to savants, common. (Up­dated from Dragon Magazine.)
Category:Wizard Spells
Category:Spells from Wizard's Spell Compendium
Category:Spells