['In 1936, Russian scientist Vladimir Lukyanov was confronted with the problem of devising a system to improve the qual...', 'In 1936, Russian scientist Vladimir Lukyanov was confronted with the problem of devising a system to improve the qual...']

['An iconic sight in the Democratic People’s Republic of Korea is the Kimjongilia. This hybrid begonia was bred by a Ja...', 'An iconic sight in the Democratic People’s Republic of Korea is the Kimjongilia. This hybrid begonia was bred by a Ja...']

['According to a 1957 US government study entitled The Effect of Nuclear Explosions on Commercially Packaged Beverages,...', 'According to a 1957 US government study entitled The Effect of Nuclear Explosions on Commercially Packaged Beverages,...']

['By the 1840s the British Empire was at full tilt, operating colonies on every continent apart from Antarctica. Key fo...', 'By the 1840s the British Empire was at full tilt, operating colonies on every continent apart from Antarctica. Key fo...']

['Götz von Berlichingen (1480-1562) was a German knight and warrior for hire in the first half of the 16th century. In...', 'Götz von Berlichingen (1480-1562) was a German knight and warrior for hire in the first half of the 16th century. In...']

['The introduction of non-native species can be a tricky business. The feral camels of Australia are a case in point. T...', 'The introduction of non-native species can be a tricky business. The feral camels of Australia are a case in point. T...']

['Shortly after aluminum was first discovered in the early 19th century it was counted among the most precious metals o...', 'Shortly after aluminum was first discovered in the early 19th century it was counted among the most precious metals o...']

['Zanzibar, an island nation that is now part of Tanzania, has been a contested territory for centuries. Starting in th...', 'Zanzibar, an island nation that is now part of Tanzania, has been a contested territory for centuries. Starting in th...']

['The height of Mount Everest was not calculated by George Everest, but by a brilliant mathematician who has since been...', 'The height of Mount Everest was not calculated by George Everest, but by a brilliant mathematician who has since been...']

['In the early 1960s, General Electric proposed a system whereby an astronaut in a space emergency might abandon ship a...', 'In the early 1960s, General Electric proposed a system whereby an astronaut in a space emergency might abandon ship a...']