Wizard Eye

When this spell is employed, the magic-user creates an invisible sensory organ which sends visual information to him or her. 

The wizard eye travels at 3" per round, viewing an area ahead as a human would or 1" per round examining the ceiling and walls as well as the floor ahead and casually viewing the walls ahead. The wizard eye can "see" with infravision at 10-ft, or it "sees" up to 60-ft distant in brightly lit areas. The wizard eye can travel in any direction as long as the spell lasts.

The material component of the spell is a bit of bat fur.

The ocular device magically formed has substance and it has form which might be detected (cf. INVISIBILITY). 

Solid objects prevent the passage of a wizard eye, although it can pass through a space no larger than a small mouse hole (about one-half inch diameter).