The caves at Lascaux were closed in 1963 because
vandals were destroying the paintings
the collective breath of the many visitors caused the paintings to corrode
the weather was destroying the paintings
the government of France wanted scholars to be able to study the work without distraction

answer: the time zones used to be whatever the local authority wanted them to be. one town might have 6am whenever the sun came up and another town had 6am 10 minutes later.  

the trains had a hard time when their orders said to be at a certain point at 6am.  

6am, but who's 6am.  

the railroads got together and set the time zones more or less along the longitude lines across the country.

explanation:

troy donahue,   i think.

first representative government in british america called virginia assembly