Cyclopedia of architecture, carpentry, and building : a general reference work (1912)
American Technical Society · Chicago : American Technical Society · leaf 72
Fig. 33. Diagram ShowingWrong Ground Layout … Fig. 34. Batter Board to Indicate Layout square and the tape measure. The accuracy of the right angle maybe checked by the use of the three-four-five rule. This rule isbased upon the fact that a triangle, whose three sides are, respectively,3, 4, and 5 feet long, is an exact right-angled triangle,…
Architecture · Building
Internet Archive · Kelly Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
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