The fleeing warders of S-21 left behind troves of documents outlining the prison's work, but it was Mr Vann Nath, painting his memories in sombre oils, who showed most vividly what had happened there.
She was a five hundred-ton boat; and besides her thirty-eight jail-birds, she carried twenty-six of a crew, eighteen soldiers, a captain, three mates, a doctor, a chaplain, and four warders.
In any case, the yeoman warders, or rather the beefeaters, continue to this day and act as sort of ceremonial guards of the tower and guides to tourists.
While there had been ravens earlier, Charles II was the first monarch to insist that they were protected, appointing a yeoman warder ravenmaster to care for them.
Perrin did not have to look back to know the sisters' three warders bringing up the rear in ordinary cloaks, or men expecting the need at any moment to outsword and carve away clear.