101. Media History Timeline: 1930s http://www.mediahistory.umn.edu/time/1930s.html

20th Century : Fourth Decade Gallery American Gothic Grant Wood, 1930 Radiovisor gave blurry orange TV picture, 1930 Scotch Tape Persistence of Memory Salvador Dali, 1931 IBM Radiotype Felix the Cat TV image> broadcast by RCA 35 mm reflex camera Germany, 1933 Nazi book burning King Kong Salvador Dali's Mae West Mechanical TV 30 line scan, 1936 Piet Mondrian's Opposition of Lines, Red and Yellow George Stibitz' Model K calculator, 1937 Paul Klee's Picture Album Time Transfixed Wire recorder invented in 1939 Photo flashbulbs replace dangerous flash powder. Nancy Drew starts solving mysteries in novels for girls. On Broadway, George and Ira Gershwin's Girl Crazy The Better Homes and Gardens Cookbook sells the first of 15,000,000 copies. "Golden Age" of radio begins in U.S. Hollywood tightens self-censorship with the Motion Picture Code. Dick and Jane "See Spot Run." Lowell Thomas begins first regular U.S. network newscast. TVs based on British mechanical system roll off factory line. Most nations use radio to educate.

102. Corrosion Of U.S. Bridges http://www.research.vt.edu/resmag/sciencecol/2001weyers.html

Engineer’s predicitons dismal for nation’s highways and bridges List by Subject Science from Virginia Tech home page Research Division Virginia Tech home page When the United States was coming out of the depths of the Great Depression, one of the solutions for reducing unemployment was to create public work programs. Part of this 1930s effort included the expansion of the highway system. Later, in the late 1950s, construction began on the present interstate highway system with the 1930s construction serving as the backbone for the main transportation routes. These highway systems were typically designed for a 50-year service life. The bridges typically need rehabilitation in 35 years and replacement in 70 years. The time has come to replace the 1930s infrastructure and rehabilitate the 1950-60s interstate system. Unfortunately, much of the replacement and rehabilitation has not even taken place. The consequences could be dismal, according to Richard Weyers (pictured here), an expert in bridge construction and a professor of civil and environmental engineering at Virginia Tech . He predicts that the bridge system alone in America is facing a trillion dollar investment. "A new structure costs $75 to $100 per square foot to build. A new bridge, on average, is 8,000 square feet. And there are about 500,000 bridges in the federal highway system, not counting any structure under 20 feet or ones on the back roads."

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