Usually they stayed awake three to four hours past sunset, with no light exposure other than the faint glow of a small fire that would keep animals away and provide a bit of warmth in the winter.

通常，他们在日落后三到四个小时里仍然清醒着，而且除了用以驱赶野生动物并在冬天聊以取暖的微弱火光之外，他们别无其他光源。

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Twenty-four hours of light bleaches out the structure of a day, so ship life becomes organized by meals and debarkations, either onto land or into the inflatable dinghies.

FORBES: Go with the Floe

Shortly after, a tremendous storm hit the Wanderers, rendering the entire ground underwater, and yet, just three hours later, a further four overs were possible before bad light ended play.

BBC: Jonathan Agnew column