Event:
William Harvey of England discovers blood circulation
More Notable Events on April 1:
1991 Iran releases British hostage Roger Cooper after 5 years
1991 U.S. minimum wage goes from $3.80 to $4.25 per hour
1986 World oil prices dip below $10 a barrel
1982 U.S. formally transfers Canal Zone to Panama
1748 Ruins of Pompeii found
