The USS Monitor, whose cross section is pictured above, was the first iron-clad warship in the US Navy. Built during the U.S. Civil War, it was famous for its revolving turret, fitted out with a cannon. Now, a group is restoring the cannon — and you can see some unbelievable before-and-after pictures below.
The USS Monitor lab uses the latest techniques in restoration, and today they tweeted one of their triumphs: extracting and restoring the sight cover from the turret cannon. It's amazing how it looks basically melted in the first picture, then when it's extracted it looks alarmingly like tandoori chicken, and by the time they are finished, it's totally recognizable.