In 1938, scores of eyewitnesses observed the explosive roar of a huge fireball streaking over Butler County, Pa, USA. A cow was struck and injured by a falling stone. Two pieces were found of the stone meteorite, named the Chicora (for the region in which it fell), an olivine-hypersthene chondrite (amphoterite). They had masses 242g and 61g, discovered some miles short of the calculated point of impact of the main mass - which is yet to be found. The original total mass, estimated from the smoke trail and energy considerations, was 519 tons before it exploded about 12 miles up. In 1940, two more fragments were found, 400-ft from the first site. Of the eight meteorites found in the state, five were iron meteorites.«*