The court of Lisbon had a fit of cold ague and we sailed with little goodwill; therefore it was our business to confound the doubters or perish.
Already our seamen had reached the mouth of that mighty river they called the Congo, and clearly the butt of Africa could not be distant.
We had the course of Cam and Behaim to guide us thus far, but after that was the darkness." The man's face had the intent look of one who remembers with passion.
He told of the struggle to cross the Guinea Deep instead of hugging the shore; of blue idle days of calm when magic fish flew aboard and Leviathan wallowed so near that the caravels were all but overwhelmed by the wave of him; of a storm which swept the decks and washed away the Virgin on the bows of the Admiral's ship; of landfall at last in a place where the forests were knee deep in a muddy sea, strange forests where the branches twined like snakes; of a going ashore at a river mouth full of toothed serpents and giant apes, and of a fight with Behemoth among the reeds.

Then a second storm blowing from the east had flung them seaward, and for weeks they were out of sight of land, steering by strange stars.

They had their magnets and astrolabes, but it was a new world they had entered, and they trusted God rather than their wits.

At last they turned eastward.
"What distance before the turn ?" Philip asked.
"I know not.

We were far from land and no man can measure a course on water." "Nay, but the ancients could," Philip cried, and he explained how the Romans had wheels of a certain diameter fixed to their ships' sides which the water turned in its passing, and which flung for each revolution a pebble into a tally-box.
The other's eyes widened.