Nonius

1542

Nonius

The book of science

Tom Sharp

Pedro Nunes metrology astronomy

Nonius

Nonius arcs

Nonius riffs

The vernier scale was a refinement of the nonius and is still called a nonius in some languages. Both designs improve accuracy by taking advantage of our ability to recognize how closely two lines are aligned. Reliable machines for drawing and marking arcs, called dividing engines, were not available until we get to Henry Hindley around 1739.

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