A textbook on mechanical and electrical engineering (1902)
International Correspondence Schools · Scranton : International Textbook Co. · leaf 114
from A. 8. The above rule governing the direction of sectionlines is always adhered to when possible; when any depar-ture is necessary, care is taken to prevent ambiguity. Whereonly the sectional view is given, it is often very difficult tounderstand the drawing, and sometimes a violation of the S… … (a)
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