How the Allies Used Germany's Serial Numbers Against Them

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Europe and the Pacific were the two primary arenas in World War II, but the battle was also one of technological achievement. Airplanes, submarines, and of course the development of the atomic bomb were core markers to the arms race within the War. Similar, tank warfare was as much a function of innovation as it was anything else. Allied forces readily admitted that the enemy German tanks, such as the Tiger and Panther, were superior to their own. The big question for Allied forces, then, was not how to counter the Tiger and its progeny, but how many tanks Germany was able to produce.

To solve this problem, the Allies first turned to conventional intelligence gathering: spying, intercepting and decoding transmissions, interrogating captured enemies, etc. Via this method, the Allies deduced that from June 1940 to September 1942, the German military industrial complex was churning out roughly 1,400 tanks each month -- an enormous amount. By comparison, the Axis forces used "only" 1,200 tanks during the Battle of Stalingrad, an eight month battle with a total casualty count nearing 2 million people.

Perhaps skeptical of the above result, the Allies looked for other methods of estimation. And then they found a critical clue: serial numbers. Specifically, Allied intelligence noticed that each captured German tank (and wreckage thereof) contained a serial number unique to that tank. With a bit of careful observation, the Allies were able to determine that the serial numbers had a pattern denoting the order of tank production.

Using this data, the Allies were able to create a mathematical model to determine the rate of German tank production, and estimated that, during the same summer 1940 to fall 1942 time period, the Germans actually produced 255 tanks per month -- a fraction of the 1,400 estimate produced by conventional intelligence. (Want to see the math? Click here.) And it turns out, this method worked best: after the War, internal German data put the number at 256 tanks per month.

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Ernest Hemingway’s Guide to Life, In 20 Quotes
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Though he made his living as a writer, Ernest Hemingway was just as famous for his lust for adventure. Whether he was running with the bulls in Pamplona, fishing for marlin in Bimini, throwing back rum cocktails in Havana, or hanging out with his six-toed cats in Key West, the Nobel and Pulitzer Prize-winning author never did anything halfway. And he used his adventures as fodder for the unparalleled collection of novels, short stories, and nonfiction books he left behind, The Sun Also Rises, A Farewell to Arms, Death in the Afternoon, For Whom the Bell Tolls, and The Old Man and the Sea among them.

On what would be his 119th birthday—he was born in Oak Park, Illinois on July 21, 1899—here are 20 memorable quotes that offer a keen perspective into Hemingway’s way of life.

ON THE IMPORTANCE OF LISTENING

"I like to listen. I have learned a great deal from listening carefully. Most people never listen."

ON TRUST

"The best way to find out if you can trust somebody is to trust them."

ON DECIDING WHAT TO WRITE ABOUT

"I never had to choose a subject—my subject rather chose me."

ON TRAVEL

"Never go on trips with anyone you do not love."


Ernest Hemingway Photograph Collection, John F. Kennedy Presidential Library and Museum, Boston. [1], Public Domain, Wikimedia Commons

ON THE RELATIONSHIP BETWEEN INTELLIGENCE AND HAPPINESS

"Happiness in intelligent people is the rarest thing I know."

ON TRUTH

"There's no one thing that is true. They're all true."

ON THE DOWNSIDE OF PEOPLE

"The only thing that could spoil a day was people. People were always the limiters of happiness, except for the very few that were as good as spring itself."

ON SUFFERING FOR YOUR ART

"There is nothing to writing. All you do is sit down at a typewriter and bleed."

ON TAKING ACTION

"Never mistake motion for action."

ON GETTING WORDS OUT

"I wake up in the morning and my mind starts making sentences, and I have to get rid of them fast—talk them or write them down."


Photograph by Mary Hemingway, in the Ernest Hemingway Photograph Collection, John F. Kennedy Presidential Library and Museum, Boston., Public Domain, Wikimedia Commons

ON THE BENEFITS OF SLEEP

"I love sleep. My life has the tendency to fall apart when I'm awake, you know?"

ON FINDING STRENGTH 

"The world breaks everyone, and afterward, some are strong at the broken places."

ON THE TRUE NATURE OF WICKEDNESS

"All things truly wicked start from innocence."

ON WRITING WHAT YOU KNOW

"If a writer knows enough about what he is writing about, he may omit things that he knows. The dignity of movement of an iceberg is due to only one ninth of it being above water."

ON THE DEFINITION OF COURAGE

"Courage is grace under pressure."

ON THE PAINFULNESS OF BEING FUNNY

"A man's got to take a lot of punishment to write a really funny book."


By Ernest Hemingway Photograph Collection, John F. Kennedy Presidential Library and Museum, Boston. - JFK Library, Public Domain, Wikimedia Commons

ON KEEPING PROMISES

"Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut."

ON GOOD VS. EVIL

"About morals, I know only that what is moral is what you feel good after and what is immoral is what you feel bad after."

ON REACHING FOR THE UNATTAINABLE

"For a true writer, each book should be a new beginning where he tries again for something that is beyond attainment. He should always try for something that has never been done or that others have tried and failed. Then sometimes, with great luck, he will succeed."

ON HAPPY ENDINGS

"There is no lonelier man in death, except the suicide, than that man who has lived many years with a good wife and then outlived her. If two people love each other there can be no happy end to it."

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