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Chapter 27
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The words "Under god is added to the pledge of allegience
he Pledge of Allegiance of the United States is an expression of loyalty to the federal flag and the republic of the United States of America, originally composed by Christian Socialist Francis Bellamy (1855-1931) in 1892 and formally adopted by Congress as the pledge in 1942.[1] The Pledge has been modified four times since its composition, with the most recent change adding the words "under God" in 1954. -
Transistor was invented
The first transistor was invented at Bell Laboratories on December 16, 1947 by William Shockley (seated at Brattain's laboratory bench), John Bardeen (left) and Walter Brattain (right). This was perhaps the most important electronics event of the 20th century, as it later made possible the integrated circuit and microprocessor that are the basis of modern electronics. Prior to the transistor the only alternative to its current regulation and switching functions (TRANSfer resISTOR) was the vacuum -
First White house broad casting
On this day in 1951, President Harry S. Truman's opening speech before a conference in San Francisco is broadcast across the nation, marking the first time a television program was broadcast from coast to coast. The speech focused on Truman's acceptance of a treaty that officially ended America's post-World War II occupation of Japan. -
The polio vaccine was invented
Two polio vaccines are used throughout the world to combat poliomyelitis (or polio). The first was developed by Jonas Salk and first tested in 1952. Announced to the world by Salk on April 12, 1955, it consists of an injected dose of inactivated (dead) poliovirus. An oral vaccine was developed by Albert Sabin using attenuated poliovirus. Human trials of Sabin's vaccine began in 1957 and it was licensed in 1962.[1] Because there is no long term carrier state for poliovirus in immunocompetent indi -
First nuclear powerplant
located near the present-day Beaver Valley Nuclear Generating Station on the Ohio River in Beaver County, Pennsylvania, USA, about 25 miles (40 km) from Pittsburgh. The reactor went online December 2, 1957, and was in operation until October, 1982 -
NASA is established
The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research. Since February 2006, NASA's mission statement has been to "pioneer the future in space exploration, scientific discovery and aeronautics research." [5] On September 14, 2011, NASA announced that it had selected the design of a new Space Launch System that it said would take the agency's astro
