In this article, we will discuss burel hand level.
1. Introduction – Burel Hand Level
Burel Hand Level consists of a simple frame carrying a mirror and plain glass. The mirror extends halfway across the frame. The plain glass extends to another half. The frame can be suspended vertically in gambles.
The edge of the mirror forms a vertical reference.
The instrument is based on the principle that a ray of light after being reflected back from a vertical mirror along the path of incidence, is horizontal.
When the instrument is suspended at eye level, the image of the eye is visible at the edge of the mirror, while the objects appearing through the plain glass opposite the image of the eye are at the level of the observers’ eye.
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