It was a short half block to the flea trap we called home. We kept out of it as much as we could, holding our long daily conferences across the street at the Novedades. The roaches scurried as we passed up the dark stairway to our not much brighter room. I crossed to the bureau and opened a drawer.
"The globe," Foster said, taking it in his hands. "I wonder if perhaps he meant a ten-thousandth part of the circumference of the earth?"
"What would he know about——"
"Disregard the anachronistic aspect of it," Foster said. "The man who wrote the book knew many things. We'll have to start with some assumptions. Let's make the obvious ones: that we're looking for a plain on the west coast of Europe, lying——" He pulled a chair up to the scabrous table and riffled through to one of my scribbled sheets: "50/10,000s of the circumference of the earth—that would be about 125 miles—west of a chalk formation, and 3675 miles north of a median line...."
"Maybe," I said, "he means the Equator."
"Certainly. Why not? That would mean our plain lies on a line through——" he studied the small globe "——Warsaw, and south of Amsterdam."
"But this part about a rock outcropping," I said. "How do we find out if there's any conspicuous chalk formation around there?"
"We can consult a geology text. There may be a library in this neighborhood."
"The only chalk deposits I ever heard about," I said, "are the White cliffs of Dover."
"White cliffs...."