Galvanic corrosion is a process that degrades metals electrochemically. This corrosion occurs when two dissimilar metals are located in contact with each other in the presence of an electrolyte, such as salt water, forming a galvanic cell.
But the memories of that tragic day 25 years ago are still vivid to many in Edmond. On Aug. 20, 1986, gunman Patrick Henry Sherrill shot and killed 14 co-workers, wounded six and then took his own life inside the post office where he worked.
The earliest known shooting to happen on school property in the US was the Pontiacs rebellion school massacre on July 26, 1764, where four Lenape American Indians entered the schoolhouse near present day Greencastle, Pennsylvania, shot and killed schoolmaster Enoch Brown, and killed nine or ten children (reports vary). Only three children survived.