Description
If you haven’t heard of the sector, it probably means you aren’t an artillery officer or a ship’s navigator working in the 16th century! An invention attributed to the great astronomer Galileo, the sector was a calculation instrument used with a pair of dividers to derive proportions, polygons, trigonometric and numerous other table functions. By the mid 1700’s, cabinetmakers such as Thomas Sheraton were advocating the sector’s use in layout work.
With the paper sector and detailed instructions offered here (for less than the price of a movie without popcorn) you will be able to quickly create equal segments between two points; derive harmonic proportional relationships; generate angled lines to certain rise-to-run pitches; set out the facets or arcs of polygons (up to twelve sides); determine the circumference of a circle knowing its radius; and find out what your brother-in-law really does for a living.You’re going to wonder how you ever made do without one!
