Gerard

A few hundred years later, Belgian cartographer Gerard Mercator was charged with heresy.

And only Gerard himself knew the history of service in the face of death comprehended in the simple statement.

I'm saying it; Gerard cut him off from getting past, and he pitched a wrench that knocked him out.

"I wish you had been with us, Corrie," was all Gerard found to say.

Gerard would soon find the right cure for that sort of complaint, he said, when the real business of the trip should begin.

The author then quotes the passage from Gerard where mention is made of the Barnacle.