J. Leonard Johnson

James Leonard Vincent Johnson, (1905-1966) was an American scientist.

"Len" Johnson as he was known was an important American designer and scientist in the mid-twentieth century in the field of metallurgy and nuclear technology. He was one of the first Irish Catholics to break into the exclusive field of design engineering for the Department of Defense.

Len Johnson was born in Freeland, Schuylkill County, Pennsylvania, in the heart of the coal fields. His father, John Joseph Johnson or "Jack" was the first Irish boss of the huge Cox Coal Company. It is estimated that Jack directed well over 1000 workers on a day to day basis. Jack was selected to be the first Irish boss because of his intelligence and popularity. He was educated formally and then placed in charge of the entire field. That position allowed his son, Len, to enter into the prestigious Mining and Mechanical School, where he graduated in 1922.

From there, Len became the first of his ilk to attend college. It was a difficult decision to make in that he was offered a job with the professional baseball team, the St. Louis Browns. However, Len chose to attend college instead. He went to Pennsylvania State College (now University) and graduated with a degree in Mechanical Engineering in 1926. From there he returned to the coal fields for a short time in the 1920s, but eventually went to work for the National Tube company in Elyria, Ohio. There he stayed until the late 1930s when he came to notice of U.S. Steel for his ability to design new metal products.

World War II

U.S. Steel was starting to advance their weaponry design department in preparation for what would become World War II. Len went into the steel weapons design department and was on the team that first issued the patent for rolled steel artillery shells, replacing those that were cast iron. This advancement increased the effective range of artillery shrapnel out to fifty meters. Another design patent he made was the aluminum fuel blivet that would roll behind a jeep. Both designs are still used by the military today.

The Manhattan Project

For the majority of the war, Len and his family lived in Pittsburgh and worked on new metallic products. However, his design expertise brought him to the attention of the top secret Department of Defense project to develop an Atomic Bomb. He was brought into the Manhattan Project in the early 1940s and given a team whose job it was to develop two separate metallic imploding bomb casings. These two designs were later named "Fatman" and "Little Boy". As was common at that time, each cell of the Manhattan Project did not know exactly what it was that they were building. Such was the case for Len's design team. They did not realize it was the Atomic bomb that they had worked on until the detonations over Japan in 1945.

Family History

Although his last name was Johnson, Len could have been named O'Neill. He descended from the ancient Irish royal family that lived in northern Ireland. His descent from this well known family was confirmed when the Vatican recognized his paternal genealogy in the 1930s as being of the royal line.Fact|date=July 2008