Abstract: A level formed by a frame having opposing longitudinal working surfaces and a transverse opening in the frame supporting a ring assembly for angular rotation in a longitudinal plane of the frame. A spheroid vial containing a bubble indicator is supported by the ring assembly with its major axis extending diametrically across the inner periphery of the ring assembly to register a level position when the major axis of the vial is disposed in a horizontal plane. Angle indicating indicia is scored on the surface of plates abutting opposing sides of the frame and maintaining the ring assembly within the frame opening for indicating selective angular alignment of the major axis of the vial with respect to the plane of the working surface whereby preselected orientation of the vial with the angle indicia indicates a preselected angular relationship of the vial major axis and a working surface when the working surface is in contact with the surface being measured.

Abstract: A support body is provided defining a first pair of sides, a circular recess in the body opening outwardly of the first pair of sides and a second pair of sides for abutting against a surface whose orientation relative to the horizontal is to be measured. A level element is adjustably, rotatably disposed in the recess and defines a hollow housing having opposite sides including at least one outer side facing outwardly of the recess. The opposite sides include central journal bearing structures and the opposite ends of a support shaft are journaled from the journal bearing structures. A weighted pendulum-type upstanding pointer arm has a midportion thereof supported from the shaft and includes an upper end indicator or portion swingable in close proximity to the inner surface of the outer periphery of the outer side of the housing, the outer periphery being constructed of transparent material and provided with peripherally spaced indicia.