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The Nazi Plot to Blow Up Hoover Dam

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In 1935, Hoover Dam (or Boulder Dam) was a brand-spanking-new feat of engineering, dedicated in a ceremony attended by Franklin D. Roosevelt in September of that year. Less than four years later, government officials feared it would all be demolished by Nazis.

A number of suspicious activities were reported beginning in October 1939, including a German man who took large numbers of photographs around the dam and was upset when his female companion accidentally strayed into some of the shots.

By November, the State Department had word from the U.S. embassy in Mexico that two German agents planned to bomb the dam’s intake towers and cut power to the high-voltage line, with the goal of crippling the aviation manufacturing industry in Los Angeles, which did indeed rely heavily on the hydroelectric power provided by the dam. The agents planned to rent a boat under the guise of a fishing excursion, and would then use the boat to plant the bombs at the intake towers. One of the German agents had reportedly already made more than a dozen planning trips to the dam.

Officials took the threat quite seriously, immediately halting all recreational activity on Lake Mead. The restrictions applied to employees as well, which the War Department believed to be the biggest threat. None of them were allowed to enter the dam except when absolutely necessary from an operations standpoint.

Even with the precautionary measures, strange activity continued in the area. Shots were fired at a National Park Service patrol boat, and an unauthorized car was spotted driving away from a no-trespassing zone near the switchyard.

Though the discovery of the Nazi plan wasn’t made public, people noticed the sudden restrictions. Rumors began to circulate; one popular theory pertained to a massive net stretched across the lake, just above the dam, to catch any explosive devices that might be thrown at the structure. To calm the public, Bureau of Reclamation Commissioner John Page issued a press release in January 1940 saying that “Boulder Dam is perfectly safe. There has been no ‘plot’ unearthed. Reports that the Bureau of Reclamation is fearful that someone will dynamite the dam are ridiculous.”

Meanwhile, the Bureau was actually trying to figure out more advanced ways to protect the dam than access restriction and extra patrol. One “color consultant” recommended painting the dam and spillways with “bold, simple masses of colors” to help conceal the dam from planes overhead. Another proposal included building a three-quarter size “dummy” dam downstream from the real one. The decoy would be made of wire, then painted various colors and textures to simulate the concrete and rocks of the cliffs.

Despite all of the behind-the-scenes plotting and planning to protect Hoover Dam, the government continued to keep the plot from going public—and, in fact, none of this was discovered until 60 years later. In 2001, a historian for the Bureau of Reclamation happened upon government documents while doing research in the National Archives. The previously classified information revealed what citizens had been told was a completely unfounded fear: The Nazis had planned to blow up Hoover Dam.

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6 Radiant Facts About Irène Joliot-Curie
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Though her accomplishments are often overshadowed by those of her parents, the elder daughter of Marie and Pierre Curie was a brilliant researcher in her own right.


A black and white photo of Irene and Marie Curie in the laboratory in 1925.
Irène and Marie in the laboratory, 1925.
Wellcome Images, Wikimedia Commons // CC BY 4.0

Irène’s birth in Paris in 1897 launched what would become a world-changing scientific dynasty. A restless Marie rejoined her loving husband in the laboratory shortly after the baby’s arrival. Over the next 10 years, the Curies discovered radium and polonium, founded the science of radioactivity, welcomed a second daughter, Eve, and won a Nobel Prize in Physics. The Curies expected their daughters to excel in their education and their work. And excel they did; by 1925, Irène had a doctorate in chemistry and was working in her mother’s laboratory.


Like her mother, Irène fell in love in the lab—both with her work and with another scientist. Frédéric Joliot joined the Curie team as an assistant. He and Irène quickly bonded over shared interests in sports, the arts, and human rights. The two began collaborating on research and soon married, equitably combining their names and signing their work Irène and Frédéric Joliot-Curie.


Black and white photo of Irène and Fréderic Joliot-Curie working side by side in their laboratory.
Bibliothèque Nationale de France, Wikimedia Commons // Public Domain

Their passion for exploration drove them ever onward into exciting new territory. A decade of experimentation yielded advances in several disciplines. They learned how the thyroid gland absorbs radioiodine and how the body metabolizes radioactive phosphates. They found ways to coax radioactive isotopes from ordinarily non-radioactive materials—a discovery that would eventually enable both nuclear power and atomic weaponry, and one that earned them the Nobel Prize in Chemistry in 1935.


The humanist principles that initially drew Irène and Frédéric together only deepened as they grew older. Both were proud members of the Socialist Party and the Comité de Vigilance des Intellectuels Antifascistes (Vigilance Committee of Anti-Fascist Intellectuals). They took great pains to keep atomic research out of Nazi hands, sealing and hiding their research as Germany occupied their country, Irène also served as undersecretary of state for scientific research of the Popular Front government.


Irène eventually scaled back her time in the lab to raise her children Hélène and Pierre. But she never slowed down, nor did she stop fighting for equality and freedom for all. Especially active in women’s rights groups, she became a member of the Comité National de l'Union des Femmes Françaises and the World Peace Council.


Irène’s extraordinary life was a mirror of her mother’s. Tragically, her death was, too. Years of watching radiation poisoning and cancer taking their toll on Marie never dissuaded Irène from her work. In 1956, dying of leukemia, she entered the Curie Hospital, where she followed her mother’s luminous footsteps into the great beyond.

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Live Smarter
You Can Now Order Food Through Facebook
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After a bit of controversy over its way of aggregating news feeds and some questionable content censoring policies, it’s nice to have Facebook roll out a feature everyone can agree on: allowing you to order food without leaving the social media site.

According to a press release, Facebook says that the company decided to begin offering food delivery options after realizing that many of its users come to the social media hub to rate and discuss local eateries. Rather than hop from Facebook to the restaurant or a delivery service, you’ll be able to stay within the app and select from a menu of food choices. Just click “Order Food” from the Explore menu on a desktop interface or under the “More” option on Android or iOS devices. There, you’ll be presented with options that will accept takeout or delivery orders, as well as businesses participating with services like or EatStreet.

If you need to sign up and create an account with or Jimmy John’s, for example, you can do that without leaving Facebook. The feature is expected to be available nationally, effective immediately.

[h/t Forbes]


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