A fat spot of rain hit my arm and a gust of wind nearly separated me from my hat. The weather changed rapidly in this part of the world—we always had to be ready for it, and Mr. Darwin’s blue-gray eyes looked dark beneath his frown. I shouldered our knapsacks and stowed the logbook in my satchel. Mr. Darwin’s eyeglass had been discarded on a boulder, and I slipped it inside my fiddle case, then thumbed some wax around the seals to keep out the water. I’d brought my fiddle as an experiment to see the effect of music on wildlife, but there’d been no time to play in the end. Mr. Darwin wasn’t partial to the old instrument; he called it Scratch and the name stuck.

The spatters of warm rain turned into a downpour, and we hurried across the black lava plain toward the shore where the rowboat waited.

“Watch your step here, Syms,” said Mr. Darwin, and I nodded. Beneath the lava plain were tunnels, which had once been underground rivers of molten lava, and there were dangerous holes near the surface.

Mr. Darwin said these islands looked like the infernal regions—which to the likes of you and me means hell. The five volcanoes of Albemarle lined up behind us, and ahead, purple-gray clouds the shape of cauliflower had piled behind the silhouette of the Beagle, which was anchored out at sea.

One of the sailors, Robbins, met us at the shore in a bit of a lather, which wasn’t like him at all. “You’ve seen the storm, then, sir?”

Mr. Darwin nodded. “Let’s get back to the ship. All haste.”

Robbins took Mr. Darwin’s equipment and made giant strides through the bright green seaweed that covered the black rocks. We tramped straight into the sea, wading out to the rowboat, which was held steady in the surf by the other seaman, Tanner. I helped my master in first, then scrambled in myself. It had been minutes since our tortoise ride, but the Beagle was now near invisible through the rain, and the sea was dark and spiked. Robbins pushed off from the shore and waded through the surf, then leaped in behind us.

“Hold tight, lad. Mr. Darwin.”

The two men began to row, muscles cording at their necks, as the swell of the sea rose and rain pelted us like stones thrown by a furious beast.

Lightning split the dark clouds above us, and thunder shook my bones. From the first lurch of the rowboat, Mr. Darwin’s face turned the color of ship’s porridge, as it always did in any sort of swell. But as we pitched and rolled our way toward the Beagle, it was Robbins’s stony face that scared me. He and Tanner were rowing with all their strength, but the waves were rising, the wind sharper than the bosun’s whip, and it was hard to say if we were any closer to the ship.