Here is an excerpt of how the info is presented in the program (from the "transcript" section of the Nova page at
NARRATOR: Joining the two bronze alloys reveals the Qin's impressive technical sophistication and innovative production skills. But only a test can show if the replica arrowheads perform in practice.
Ancient Chinese sources give clues to how the bows that shot them were loaded.
MIKE LOADES: We have some evidence that the Qin laid on their backs to span their bows. That would suggest pretty powerful bows of about 200 pounds, which is more powerful than a hand-bow is going to be.
NARRATOR: Mike's demonstration bow replicates the mechanism of an authentic Qin bow, but only creates a quarter of the force.
MIKE LOADES: And we're now shooting with more than four times the power.
NARRATOR: To test the replica arrows to the limit, he's using a modern bow, with the 200-pound draw weight of the original Qin bows. It's devastating against ballistic gel, but how will it fare against Chinese armor?
MIKE LOADES: This is the level of armor that an arrow has to defeat. It's lamellar armor. That means you've got scales, which overlap each other, and then, behind that, is soft textile armor. And you can see on the terracotta warriors, they're wearing quite bulky clothing. And armor is a composite defense of hard exterior with soft padding, and they've probably got felt coats under that. Deep inside, here, is a piece of pork, to represent the human being inside. So that's the challenge an arrowhead has. Delivering that crucial thump to the target.
Safety off.
Well, it's stuck in. It's done something, by god, and its gone right through the pork. That is a dead enemy.
It's actually gone right through, and it's come out the other side, through the pork. Through three layers of hardened leather, through multiple layers of gathered silk, through a thick piece of felt, through a side of pork, and here it is, out the other side.
NARRATOR: The Qin used the crossbow to powerful effect. In 223 B.C., the Qin faced the vast Chu army on the banks of the Yangtze River. The Qin tricked them and then attacked with their devastating archers.
MIKE LOADES: This seemingly simple mechanism is two millennia ahead of its time.
NARRATOR: It would take over 1,500 years for European crossbows to surpass the Chinese ones in power, and only then with cumbersome levers and pulleys, making them far slower to use and difficult to master.
MIKE LOADES: You can learn to use this in less than two minutes. And it enabled a peasant army to be converted into state of the art troops.
NARRATOR: The Qin army had become so well organized and equipped, it conquered all its rivals and ended two centuries of war. The Qin leader now ruled all China, as the first emperor.