If physicist Amelia Sparavigna is correct, in addition to frogs, lice, and locusts, Egyptian schoolchildren were also plagued with useless geometry instruments in their new notebooks at the beginning of every school year. A mysterious object was found in the architect Kha's tomb in 1906 and its function has remained the subject of debate ever since. Sparavigna is certain the object is actually the world's first protractor
. From the article: "The key, she says, lies in the numbers encoded in the object's ornate decoration
,(Pdf) which resembles a compass rose with 16 evenly spaced petals surrounded by a circular zigzag with 36 corners."