Simplify the following text for a Grade 10 native English-speaking person.
Original: The bean machine , also known as the quincunx or Galton box , is a device invented by Sir Francis Galton to demonstrate the central limit theorem and the normal distribution .
Simplified: The bean machine , also known as the quincunx or Galton box , is a machine invented by Sir Francis Galton to demonstrate the law of error and the normal distribution .