How Old Is It? The Story of Dating in Archeaology

The absolute clock utilized most widely in archaeology is the historical record. Men have used calendars for a long time, and have often left records with written dates. On tombstones at a site in old Virginia, on the pedestals of statues and other monuments from classical Greece and Rome, on the walls of the tombs of Egyptian kings, dates are clearly inscribed which can be related to the sites dug into by the archaeologists.

These dates must often be recalculated in terms of the Christian calendar which we use. Most calendars in use in the Mediterranean, the Near East and China during classical antiquity have been successfully correlated with the one we use today, and a date inscribed or noted on such sites can be considered in our own terms. Other calendars, such as those developed in the ancient cultures of the Maya on the Yucatan Peninsula, have yet to be accurately correlated with our own. Such calendars can be used on their own terms of course, and a site which has an inscription in the Mayan calendar is known to be so many years older or younger than another one with a different date in that calendar. We speak of such a situation as a floating chronology. That is, the sequence of events and the number of years which separate them are known, but the dates of those events in absolute time are unknown.