section_path: History/Antiquity/The Sand Reckoner
section_name: The Sand Reckoner
paragraph_text: The Sand Reckoner
  
  In The Sand Reckoner, Archimedes proved the law of exponents, 10 · 10 = 10, necessary to manipulate powers of 10. He then used powers of 10 to estimate the number of grains of sand that can be contained in the universe.