Blast from the Analog Past! Physicist Identifies First Protractor

Egyptian artifact identified as world's first known .

And now a controversial look back… way back.

Physicist Amelia Sparavigna recently identified an artifact in a Turin museum as the world’s first known protractor. Sparavigna argues that the artifact’s ornate decoration, which resembles a compass rose with 16 evenly spaced petals surrounded by a zigzag with 36 corners, was used in combination with a plumb line to measure the slope angle of an object beneath it.