A-frame level

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A-frame level

tool

Learn about this topic in these articles:

development of levels

In hand tool: Plumb line, level, and square
The Egyptians used an A-frame, on which a plumb line was suspended from the vertex of the A. When the feet of the A were set on the surface to be checked, if the plumb line bisected the crossbar of the A, the surface was horizontal. The A-frame level…
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