Take Shabbat, for example—we begin and end at a precise minute, and one that varies from week to week. I always wondered, however, exactly how did people know when to light Shabbat candles in an era before clocks and watches were household items. I assume most people did not own a sundial and you can’t always rely on the skies. So how did they know it was 4:53 pm and time to light the candles? Or that the eighteen minutes were up and you had to park your horse and walk home?He showed various examples of old calendars. I don't have much to add, but I did come across some interesting examples in 1842 issues of the British periodical Voice of Jacob:
A few years ago I discovered the answer of how they knew the difference between 4:53 and 5:07.
Answer: they couldn’t tell the difference.
As you can see, people were told that candle-lighting time was on the half-hour or on the hour, for basically four weeks in a row. Then the time moved forward by a half-hour.
In case anyone is tempted to think that this was an ignorant periodical, unconcerned about zemanim, below is a discussion about זמן קריאת שמע.
Finally, I thought this add was fantastic; someone wants to buy a sukkah, so he asks if anyone has a good size Tabernacle to sell.