Happy Birthday to the Richter Scale inventor: It's National Richter Scale Day - CBS Los Angeles

The Richter Scale measures quakes in a range from 0 to 9. On the scale, each increase in number represents an earthquake 10 times more powerful.

NATIONAL RICHTER SCALE DAY: National Richter Scale Day on April 26

National Richter Scale Day, Date, History, Celebration

Guinness World Records 2014

Art Blog Kate Vass Galerie — Kate Vass Galerie

NATIONAL RICHTER SCALE DAY - April 26 - National Day Calendar

Richter Scale's developer was a scientist with Butler County roots

NATIONAL RICHTER SCALE DAY - April 26 - National Day Calendar

Art Blog Kate Vass Galerie — Kate Vass Galerie

1981–82 Volume 105 No 1–5 - Phi Delta Theta Scroll Archive