Book Review by Philip Matyszak
In the modern world, time is not something we can easily escape. Most people carry wristwatches and clocks are everywhere, from the digital readout on a computer to the tower on the town hall.
Yet as Robert Hannah reminds us, there was a time before men were slaves of the clock. A time when one's stomach was 'the best and truest' timekeeper (Plautus) and people slept and ate when they felt the need.
Yet those days were gone almost at the start of recorded history. When humans started to keep track of what they were doing, they also started to keep track of time. This charming little book (206 pages) is the story of that endeavour, and is in its own way as fine a piece of craftsmanship as some of the time pieces it so lovingly describes.
We start with that oldest of timepieces which still works well today - the sky. Chapter 1 'Cosmic Time' takes the reader through the relatively familiar solstices and equinoxes, and shows that, by an interesting co-incidence, the sun rises over Mt Lykabettos when viewed from the Pynx at midsummer.
From there we move on to the 'zodiac' - a word which means 'little animals' - and how to tell the seasons by the rising and setting of certain constellations. This is explained in detail, and by detail, I mean that here and elsewhere in the book the author gets highly mathematical - to the point where an advanced keyboard would be required to show a sample of the text.
The layout of the book means that those who want to check the author's algebra can do so, while the rest can take his word for it, skip those sections and get on with the more human elements of the story.
There is for example the fascinating detail that the first sundials were probably the human body. One could tell the time by facing away from the sun and pacing out the length of one's shadow. So a dinner invitation might be for when 'the sun is at eleven feet.' Since taller people have bigger feet, the height of the person doing the measuring makes relatively little difference.
We also learn that time in antiquity was a very fluid concept. Most places used the lunar month and the solar year, but as the lunar month does not fit into the solar year, extra months had to be added occasionally to keep the two synchronized. Every city did this differently, called the months different names, and did not even agree on when the year started.
Even the hour was flexible - there were twelve hours between sunrise and sunset, so hours were longer in summer than in winter. Those devices such as water clocks which measured hours more exactly had to be adjusted to fit the ever-changing length of the 'real' thing. In later years sundials became ever more sophisticated and were supplemented by devices such as water clocks. These are described in detail and in all their variety - from the huge sundial near the tomb of Augustus to portable devices that could be carried like pocket watches.
Nor were the ancients unsophisticated about time - the author makes excellent use of both archaeology and ancient texts to show that people were well aware that things such as longitude and latitude affected time (for example Pliny knew that a sundial looted from Syracuse told the wrong time because sundials have to be calibrated for their latitude).
The author does a splendid job of describing all this, and of mentioning but not getting drawn into arcane controversies such as whether plane or hemispherical sundials came first, and exactly what the Antikythera Mechanism was used for.
Overall, if you ever wondered how to tell the time by the stars, and the season by the houses of the sun, you'll be fascinated by this book. And once you've seen an armillary sphere (described on p.117) you'll realize that no house is complete without one.