Think back over the chapters. A house painter spends his evenings at the South Pole without leaving his armchair. A famous explorer says his name on the radio. And then a wooden crate with air holes stands in the hallway, rocking slightly — and out steps a small, solemn gentleman in a feathered dinner jacket who inspects the house, discovers the bathtub, and turns it into a private toboggan run. The dream did not come true exactly. Something better happened: the dream arrived by mail.

Penguins are birds, yet everything about them seems backwards. Their wings cannot lift them an inch into the air — instead, they have hardened into stiff, powerful flippers that make penguins some of the fastest swimmers in the ocean. Their thick coat of tiny feathers traps a layer of warm air against the skin and works like a waterproof diving suit. On land they walk upright with a slow, rocking waddle that looks clumsy and solemn at the same time, as if each bird were a tiny gentleman on important business. Nearly all penguins live in the Southern Hemisphere — along the coasts of Antarctica, South America, Africa, and Australia — and not one lives wild at the North Pole. In the water, everything changes: the waddler becomes a torpedo, twisting and diving after fish with astonishing grace. Scientists like to say a penguin is not a bird that failed at flying. It is a bird that learned to fly underwater.

No right or wrong — close the screen and tell someone nearby what happened in this part. Can’t find anyone? Tell yourself out loud. The moment you teach it, you truly understand it.