A nomogram (from Greek nomos νόμος, "law" and grammē γραμμή, "line"), also called a nomograph, alignment chart, or abaque, is a graphical calculating device, a two-dimensional diagram designed to allow the approximate graphical computation of a mathematical function.

How do you spell Freeman?

noun, plural free·men. a person who is free; a person who enjoys personal, civil, or political liberty. a person who enjoys or is entitled to citizenship, franchise, or other special privilege: a freeman of a city.

How do you read a nomograph?

A nomograph is defined as a graph, usually containing three parallel scales graduated for different variables so that when a straight line connects values of any two, the related value may be read directly from the third vertical line at the point intersected by the line.