longitude in time

基本解释

GMT is a universal time zone, based on the Greenwich meridian corrected by the longitude of the location in which the time is set.
GMT是一種通用時區，是根據格林威治子午線，用設定時間所在位置的經度與其求差計算出來的。
Different countries in the world where the longitude location, the time of all countries are different, so the "new year" date is different.
世界各國所処的經度位置不同，各國的時間也不同，所以各國“過年”的日期也不同。
Because of the longitude of the world in different locations, countries of time is also different, accordingly, "new date there are also different."
由於世界各國所処的經度地位不同，各國的時間也不同，因而，“除夕”的日期也有不同。

The clock could tell the correct time in two places, meeting the requirements for learning longitude on the sea.

As a seafaring nation, Britain depended on accurate navigation, and determining longitude on the open ocean depended on comparing local time to the time in a place where the longitude was known.
FORBES: Magazine Article
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