For example, I gather seawater has a very specific effect on iron.

Yes, it's very challenging to conserve marine archaeological iron.

Really, it's a miracle that any of the iron survived [laughs] and this goes back to it being covered in the silt, which just cut off oxygen so corrosion couldn't happen.

Typically, you put it into a solution which just passivates it, so it stops the corrosion happening.

And there's been lots of different methods that have been used over the years, and we found that when we opened the museum, some of the methods we'd use to remove particularly chloride from seawater, that can be very damaging in combination with other things.

Soaking treatments had been done, where the level of chloride in the solution had been measured until it didn't get any higher.

So the kind of assumption was made that you'd removed it all, but unfortunately I don't think that was the case.

I'm a volunteer in the museum, and I'd like to know, do you know who came up with the idea of putting polyethylene glycol into wood to conserve it? And will it last another 50 years, or is there a danger that perhaps the polyethylene glycol might stop working one day?

For example, I gather seawater has a very specific effect on iron.

Yes, it's very challenging to conserve marine archaeological iron.

Really, it's a miracle that any of the iron survived, and this goes back to it being covered in the silt, which just cut off oxygen, so corrosion couldn't happen.

So particularly with the iron, as soon as you excavate it, the clock starts, and you need to start looking after it.

Typically, you put it into a solution which just passivates it, so it stops the corrosion happening.

And there's been lots of different methods that have been used over the years, and we found that when we opened the museum...

some of the methods we'd use to remove particularly chloride from seawater that can be very damaging in combination with other things, soaking treatments had been done where the level of chloride in the solution had been measured until it didn't get any higher.

How has the ship changed since?