what are the advantages and disadvantages of apparent solar time?

Answer 1

I guess the main advantage is that you can tell the exact time with a sundial (assuming it's sunny). The disadvantage is that every locality has its own time. It's also hard to make a mechanical clock to keep time, because solar time runs fast and slow.

When mechanical clocks were invented, the time standard became *mean* solar time, rather than true solar time, so that each noon was 24 hours exactly from the last. In the latter part of the 19th century, rapid travel and communication by railroad and telegraph made local time standards very confusing, and standard time zones were adopted.

Answer 2

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