A textbook on mechanical and electrical engineering (1902)
International Correspondence Schools · Scranton : International Textbook Co. · leaf 14
Fig. 3 Fig. 4 has two angles of 45° each, and that in Fig. 4 one of 60° andone of 30°. They are called Jk5° and 60° triangles, respect- Wq • ively. To draw a verticalline, place the T square inposition to draw a hori-zontal line, and lay the tri-angle against it, so as toform a right angle.…
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