Welcome to the Encyclopedia of Arkansas

This Day in Arkansas History

August 7, 1998

Little Rock (Pulaski County) native Wallace Coulter died. Coulter was an engineer, inventor, and entrepreneur who was co-founder and chairman of Coulter Corporation, a worldwide medical diagnostics company headquartered in Miami, Florida. The two great passions of his life were applying engineering principles to scientific research and embracing the diversity of world cultures. He invented the principle of using electronic impedance to count and size microscopic particles suspended in a fluid. The “Coulter Principle” is responsible for the current practice of hematology laboratory medicine.

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About the Encyclopedia

The CALS Encyclopedia of Arkansas is a free, authoritative source of information about the rich history, geography, and culture of Arkansas. It is updated regularly to ensure the people of Arkansas have an accurate and accessible resource to explore our heritage. We invite you to browse our text entries and media galleries to learn more about the people, places, events, legends, and lore of the 25th state. We are continually adding new entries, photographs, maps, videos, quizzes, lesson plans, and more, so check back frequently to see what’s new.

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New to Arkansas?

Our overview page covers everything you would want to know about our beautiful state, including state symbols, demographics, and more!

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