When tolerances become tighter and size becomes more critical, it becomes more important to understand the general requirements of straightness or concentricity. To illustrate this, suppose a 4 in.

emerging out of the top of his skull "Phineas Gage had a hole in his head, and ev'ryone knew that he oughta be dead. Was it fate or blind luck, though it never came clear, kept keepin' on year ...

Phineas Gage was a railway worker in 19th-century Vermont ... in Boston to see for herself what remains of The Man With The Hole In His Head. At the Oliver Zangwill Centre for Neuropsychological ...

"Phineas Gage had a hole in his head, and ev'ryone knew that he oughta be dead. Was it fate or blind luck, though it never came clear, kept keepin' on year after year…" That song by banjo man ...