German field telegraph operators at work in Warsaw. (Photo by Hulton Archive/Getty Images). 1st October 1914

Russian soldiers write home while serving on the Eastern Front during World War I, circa 1915. (Photo by Hulton Archive/Getty Images)

A glasses-free Toshiba 55-inch 3-D 4x full HD TV shows the movie, “Coraline” at the 2012 International Consumer Electronics Show at the Las Vegas Convention Center January 11, 2012 in Las Vegas, Nevada. The TVs are scheduled to be available this year and will come with embedded cameras with facial recognition capability so depending on where you are sitting, the set will adjust the viewing point for the best 3-D experience. (Photo by Ethan Miller/Getty Images)

Russian oppostion activists take part in a rally and march to Bolotnaya Square on February 4, 2012 in Moscow, Russia. Demonstrators braved temperatures as low as -20 degrees celsius as they took to the streets exactly one month before the presidential elections in protest against Vladimir Putin's efforts to return to the Kremlin for an unprecedented third term as President. (Photo by: Ilya Varlamov; Source: LiveJournal)

A wounded protester is attended before being rushed to a vehicle following violence in Independence Square in Kiev February 20, 2014. Ukrainian protesters seized back Kiev's Independence Square in fresh clashes with riot police on Thursday that left several injured and possibly two demonstrators dead. (Photo by Konstantin Chernichkin/Reuters)

A young girl sells balloons by the Yamuna River as devotees carrying idols of the Hindu god Ganesh, the deity of prosperity, immerse the idol on the last day of the ten-day-long Ganesh Chaturthi festival in Delhi, India, September 15, 2016. (Photo by Cathal McNaughton/Reuters)

Two young boys kneel on stools on either side of a round table as one uses a match to this the other's cigarette, November 12, 1928. (Photo by FPG/Getty Images)

Members of the Bearded Ladies Cabaret cross Broad St., before a march by supporters of Sen. Bernie Sanders, I-Vt., in Philadelphia, on the first day of the Democratic National Convention, July 25, 2016. (Photo by Tom Williams/CQ Roll Call/AP Images)