It's difficult to say what is more surprising about this little news story: that an apparently modern object was found in an ancient context, or that China actually let people know about it.
This seems like as good a time as any to discuss the title of this blog, In Situ. The phrase is Latin for "in place" and is used in archaeology to describe something which is in its primary context. For example, the Parthenon on the Athenian Acropolis is in situ, but its sculptural adornments spirited away to the British Musuem in the early ninteenth century by Lord Elgin are not. If a volcano erupted right now and buried you, your computer, and your cup of coffee, you would all be in situ until some archaeologist came and found you several centuries later. If the miniature watch were in situ, meaning it was used and deposited in the tomb 400 years ago, it could serve as evidence for sophisticated miniatured technology in Ming Dynasty China. (Or, as noted on Hot Cup of Joe, evidence that Hiro Nakamura was there.) More likely, however, the area is not so undisturbed as archaeologists there would like to think, and, while other objects in the tomb might be in their original mileau of cultural objects, this watch certainly isn't.
It is important to distinguish generalized context from in situ. Everything has context. To go back to our Elgin Marbles example, they certainly have a context in the British Museum: they have been there for almost two hundred years, they are surrounded by other works of art and antiquity, people travel just to see them. But they are not where they were originally intended to be, stuck on the side of the Parthenon.
Finding something in situ is the best way for archaeologists to determine the original function, appearance, and age of objects, rooms, and sites. Several storage jars found on a floor may indicate something about the use of the room or the jars themselves (like if, say, there were also a mill found in the room, grain storage would be likely). The dating of those jars helps indicate when the room was used and abandoned. Those same jars floating around in soil above the room, perhaps disturbed by later looters or agricultural activity, offer little by way of specific information that the in situ pots would. But they still have a context, belonging with everything else found in their soil level.
So why In Situ? Well, first off, it's a cool archaeology phrase. Secondly, highlighting the importance of contextual archaeology and placing archaeological news and ethics into this framework are two of my main goals in writing this blog. And third, just like the storage jars, I make most sense in context, and the field of archaeology is it. As a friend pointed out to me the other day, as I was describing how people can often be better understood in the context of their families and backgrounds: "Spoken like a true historian."