There are a couple of bronze drums that have been found in the Red River delta that have Chinese characters on them.
One of them records a place name, Huihe zhou/Hồi Hà châu, and the weight of the drum (回河州鼓重兩千百八十二).
The other one records a place name, Jiuzhen/Cửu Chân, the weight of the drum, its name (Fu/Phú), and it also appears to indicate that it was the eleventh drum in series (甄甄重六鈞五斤八両名曰富第未十一).
In the area of what we now call “China,” there was a tradition of inscribing writing on bronze ritual vessels that started very early, and it changed over time. During the early centuries of the Zhou Dynasty period, the inscriptions were at times quite long.
In the Warring States period (475-221 BC), however, most bronze inscriptions were short, recording such basic information as “the craftsmen’s names, that of the users, the region of use, and, in the case of weights and measures, also by the concrete indication of the weight or volume. A lot of items now also were inscribed with a concrete date on which they were fabricated or brought into use.”
I don’t know much about inscriptions on bronze vessels, but if the above information is correct, then these two inscriptions on bronze drums seem to combine information that was inscribed on ritual vessels with information that was inscribed on weights.
As was the case with ritual vessels, both of these bronze drums mention places, Huihe zhou/Hồi Hà châu and Jiuzhen/Cửu Chân. I have never heard of the first name, but the second name is one that the Qin Dynasty used to designate an area of what is today Vietnam. However, that name is recorded in written sources with different characters (九真).
In addition to place names, these inscriptions both mention the weight of the drums as well. This is odd, because as far as I have been able to learn, only actual weights contained inscriptions that documented their weight.
So why would a bronze drum – a ritual object – contain information about how much it weighed?
My theory is that these two drums were drums that had been taken to be melted down and forged into something else.
The Han Dynasty general, Ma Yuan, is said to have captured bronze drums in the first century AD and then had them melted and cast into the shape of a bronze horse.
As I see it, this would have been a way to take away symbols of power from local people and to create a new symbol of power for himself.
I have no idea if these drums date from the time of Ma Yuan’s expedition against the Trưng sisters’ rebellion, or if they are from earlier, but the fact that they record the weight of the drums strongly suggests to me that whoever inscribed those words on these drums was not using them for ritual purposes.
My guess is that these drums had been captured and were supposed to be melted down, but for some reason they managed to escape that fate, while others were destroyed (this would also explain why so few bronze drums contain inscriptions).
Following this theory, the place names would have indicated where the drums were captured, and the weight was recorded to indicate how much bronze would be obtained when the drums were melted.
In other words, they documented the places that had been pacified, and indicated how much bronze was available to create a new symbol of power.