Professor Julia Lovell

extraordinary army would have looked like.

You've got the unarmoured rank and file at the front, then you've got armoured fighters and archers distributed down the flanks.

And yeah, they were armed with literally cutting edge bronze weapons.

Finds in pit one included crossbow triggers, swords, lances, spears, and over 40,000 arrowheads.

So these weapons were clearly meant to be used.

Analysis has shown that blades were sharpened and many are so well preserved that they'd still be lethal today.

So the first emperor was profoundly paranoid and controlling.

On his journey to conquering China, he and his armies had killed hundreds of thousands of people from other states to the east of Qin.

As you'll remember, the pits containing the terracotta warriors are on the eastern side of the tomb complex.

And one interpretation of

is that Qin Shi Huangdi feared that his enemies in the afterlife, as in this world, would attack him from this direction.

So this monumental army of bodyguards would protect him from the vengeance of all the many people he killed in this world.

There are a few reasons.

For one, there are concerns for the safety of excavators.

A survey discovered very high levels of, surprise, mercury in the tomb.

There are underground walls with a void in the centre of the site, probably for the tomb of the emperor himself.

So all that survey information tantalisingly validates Sima Qian's remarkable description, but it also generates concerns about the stability of the site.

But I think the biggest concern is for conservation.

When the terracotta warriors were first brought out of the ground, they were brightly painted, but within minutes the colours faded after they were exposed to the air.

That's exactly right, yes.