Abstract: Disclosed is a double-bead horizontal and vertical spirit level having a transparent tube contains an air bubble, a basic liquid and bead insoluble in the basic liquid and having a density greater than that of the basic liquid. By comparing the relative positions of the air bubble and bead, the spirit level gives precise measurements. An apparatus using the spirit level and protractor can measure horizontal tilt angles of upper and lower surfaces, and vertical tilt angle of the vertical plane; it can also be further combined with a laser pen to measure the angle of elevation, distance, height of a remote object, tilt angles, draw a horizontal and plumb line. An apparatus where the long axis of spirit level is perpendicular to the axis of pivot, the long axis doesn't need to pass the axis of pivot and the space could be used to install a laser pen.

Abstract: Disclosed is a double-bead horizontal and vertical spirit level having a transparent tube contains an air bubble, a basic liquid and bead insoluble in the basic liquid and having a density greater than that of the basic liquid. By comparing the relative positions of the air bubble and bead, the spirit level gives precise measurements. An apparatus using the spirit level and protractor can measure horizontal tilt angles of upper and lower surfaces, and vertical tilt angle of the vertical plane; it can also be further combined with a laser pen to measure the angle of elevation, distance, height of a remote object, tilt angles, draw a horizontal and plumb line. An apparatus where the long axis of spirit level is perpendicular to the axis of pivot, the long axis doesn't need to pass the axis of pivot and the space could be used to install a laser pen.