Sometimes the annotations were marks of difference rather than similarity between the Pequod of “Moby-Dick” and the Polar Pioneer of my voyage. “Supreme lord and dictator” is how Melville describes Captain Ahab. Beside that sentence I wrote, “And here I sit, on the bridge, behind Captain Yuri of very tolerant countenance.” I should say that “very tolerant countenance” is not in my everyday speech. But by this point the book was working its way into me — as was the surrounding landscape. As I read on and traveled on, the superficial annotations marking echoes and variations became increasingly sparse: In iceberg country, the bulk of experience lies beneath the surface.

“Moby-Dick” and Antarctica have this in common: At the very start you stand amazed, believing you’ve experienced “the great flood-gates of the wonder-world swung open,” and it is only when you are further in that you look back upon that beginning (of book, of voyage along the continent) and are startled by how ordinary it seems compared with where you now are. The day I started to read the book was also our first landing via inflatable Zodiac crafts, in which we skimmed along the calm water toward the Aitcho Islands of the South Shetlands and visited our first penguin colony. How feverishly we all reached for our cameras and took pictures of the first, lone penguin that walked past our party; how we gasped in amazement at the first Weddell seal moving across the snow like a slug.

We knew nothing then of what was yet to come: the sculpture parks of icebergs; the elephant seal pups that would lie on our legs and consent to being stroked; the hissing, jabbing, pecking battles between skuas and penguins for penguin eggs on the verge of hatching; the sailing into the caldera of an active volcano; the whale pods swimming alongside the ship, raising their flukes above the surface ever so often — a sight that Melville described as “perhaps the grandest sight to be seen in all animated nature.” All these sights were still unimagined when, back on the bridge after Aitcho Island, I was reading the encounter of Ishmael with Queequeg the Cannibal, not recognizing that as wonderful as it was, it couldn’t possibly prepare me for the complete break with all convention, all recognized form, that Melville would embark on once he had his readers on the Pequod.

Why do people persist in claiming that “Moby-Dick” is about Ahab’s obsession with the white whale? Certainly it is a book about obsession, but it is Melville who is obsessed, with the need to capture the visible in a net of words. What else explains all those chapters about kinds of whales, parts of whales, stages of reducing a dead whale to salable components, not to mention the details of every last rivet on a whaling ship? Or, as Andrew Delbanco more elegantly puts it in his introduction to the Penguin Classics edition, “it furnishes one dazzling solution after another to the persistent literary problem of conveying to an innocent reader the palpable reality of an unfamiliar world.” Until Antarctica, I had never stepped foot anywhere that struck me so forcefully as an “unfamiliar world” in a purely physical sense. From Sugarloaf Mountain in Rio de Janeiro to the Buddhist stupas of Taxila, everything I have ever seen has been an amplified version of something I’ve seen or read about before.

Antarctica is a different matter. “How will you ever describe this to people who haven’t been here?” the other tourists asked me, over and over. The line announced itself as a challenge the first time I heard it, and everywhere I went I tried to translate the images around me into descriptive sentences, particularly the icebergs, so varied in shape and texture and even color (those blues!). It felt from the start that I would fail; the camera on my smartphone would convey more than I ever could.