A group of children run into a fountain on the South Bank on August 1, 2011 in London, England. Temperatures in the capital reached around 27 degress today and are expected to hit 30 degrees by Wednesday. (Photo by Dan Kitwood/Getty Images)

A family of children share a bath in Japan, circa 1965. (Photo by Three Lions/Hulton Archive/Getty Images)

Islamic female students practice the ancient Thai art of “Krabi Krabong” taught as a sport at the Darunsat Wittaya school on August 16, 2011 in Saraburi, Thailand. (Photo by Paula Bronstein/Getty Images)

A baby hippopotamus lies next to its mother on the first day it was presented to the public at the Zoo Berlin zoo on November 1, 2011 in Berlin, Germany. The baby hippo was born at the zoo on October 23. (Photo by Sean Gallup/Getty Images)

Festive characters perform during Harrods 26th Annual Christmas Parade on November 5, in London, England. (Photo by Steve Finn/Harrods via Getty Images)

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

The Oshkosh M-ATV – MRAP (Mine Resistant Ambush Protected) vehicle developed by the Oshkosh Corporation of Oshkosh, Wisconsin. It is designed to provide the same levels of protection as the larger and heavier previous MRAPs but with improved mobility and it is intended to replace M1114 HMMWVs. (wikipedia) (Photo by Alex Wong/Getty Images)

American film star Marilyn Monroe (Norma Jean Mortenson or Norma Jean Baker). (Photo by Keystone Features/Getty Images). 1952