What is 19. (Mach.) The proper relative position or adjustment of parts, not as to design or proportion, but with reference to smooth working; as, the engine is in line or out of line or out of line called?

line — 19. (Mach.) The proper relative position or adjustment of parts, not as to design or proportion, but with reference to smooth working; as, the engine is in line or out of line or out of line. (Webster's 1913.)

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