How Was Time Measured?
Since we mainly live in a structured society where people interact with one another or with their work, and live in families where generally mothers set times for getting up for school, for eating, etc., time does play a major role in our daily life. The clock, as we know it today, is a relatively new invention; even the pendulum clock did not exist until G. Galilei invented it in the XVI century. Before then, the measurement of time through some mechanical clock implement was not accurate enough but approximate. Sundials were known from antiquity and, if properly constructed, were able to measure time to a great accuracy, perhaps to better than a minute. Even simple sundials can give readings accurate enough to a few minutes.
Let's delve into the way daily time was measured up until not many centuries ago.Then we look at the calendar, and how the year was measured in months and days.
The day was divided into 24 hours, 12 daylight hours and 12 night hours. The daylight hours commenced at 6 a.m. and lasted till 6 p.m., like today. The difference being that 6 a.m. corresponded to the first hour of the day, which lasted till 7 a.m. when the second hour started and lasted till 8am; then the third hour started and lasted till 9am, etc. Following this pattern the 6th hour was equivalent to our 12am, the 9th hour 3pm and the 12th hour 6pm.
The night period was measured in vigils, each vigil lasting 3 hours. The first vigil started at 6pm and lasted till 9pm; the second vigil started at 9pm and lasted till midnight. The 3rd vigil started at midnight and lasted till 3am, and finally the 4th vigil lasted from 3am till 6am when the first hour of the new day would start the cycle again.
You can see this cycle explained in the adjoining picture of a wristwatch I patented some time back to tell Roman Time.
Look at the equivalent 6am/pm position on the dial which shows the Roman numeral XII and corresponding to the 12th hour of the day. Then move on to the 7am/pm position of a modern watch, indicated by the Roman numeral I: this corresponds to the completion of the 1st hour of the day; then numeral II to the 2nd hour and the 9am to the IIIth hour. The VIth hour, or midday, is shown at the Roman numeral VI hour position, which normally you would expect to see the 12th hour mark. The IXth hour of the day is now at the 3am/pm position of a modern clock reading. You may ask why I did not position the numeral XII at the top where you would normally expect it to be, and then follow the normal clockwise sequence, I, II, III, etc. The reason is that if I did that reading the modern time from this type of quadrant would require a mental conversion which can be be confusing and not very practical. With this layout, if you want to read the normal modern count just ignore the Roman numerals and glance at the positions of the hands. After all that is what we mostly do when we tell the time. The time shown by the picture indicates: 5 minutes past 3pm if you just look at the position of the two hands; or if you read the numerals it tells you that it is 5 minutes past the 9th hour. Obiuosly I assume you are reading the watch in the daytime. If it were night time, then it would still be 5 minutes past three o'clock in the morning, or 5 minutes past the 3rd vigil, or 5 minutes into the 4th vigil.
The picture shows a wristwatch with a perpetual calendar showing month, day and year from the foundation of Rome, which in Latin is abbreviated with AUC, short for Ab Urbe Condita: ab= from, Urbe=city of Rome, Condita=foundation of, i.e. 753 B.C. If you take the current year and add 753 you will obtain the time measured from AUC. I am writing this page in 2008 therefore measuring from the foundation of the City we would be in the year: MMDCCLXI (2761).
Now that you know how time was told in the day and at night, let's look at how time was expressed.
To ask the time:- Quota hora est?
Reply:- Est hora quinta or simply Hora quinta. (see the above watch)
To ask the time:- Quota hora est?
Reply:- Est secunda vigilia or simply Secunda Vigilia. (see the watch above)
If I said:- Est hora prima secunda vigilia, what do I mean? ....................................................................................... (10pm)
Note: If you are not familiar with Roman numerals please read the page Roman Numerals on this website.