The tone of these chapters is objective and businesslike, broken by a further insight into the characters of Ishmael and Ahab. The whalers are professionally interested in two things: the "blanket" of fat that forms the skin of the whale; and its head, which contains the most valuable product. The whale's blubber runs as much as fifteen inches thick and is peeled like an orange's skin. It is boiled to render the oil — about ten barrels of oil to the ton, a hundred barrels with a very large sperm whale.
When the carcass is released, Ishmael watches it float away and sees this as a doleful and mocking funeral. He compares the sea vultures, which prepare to feed on the carcass, to "air-sharks," representative of the predatory cruelty of life, especially life at sea. Ishmael is a poet-philosopher, as is Ahab, which partially explains Ishmael's deep interest in the captain.
The head of the whale is very valuable because that is where the white, wax-like spermaceti is found. The decapitated head, which constitutes a third of the leviathan's bulk, is cumbersome but necessary to the industry. Ishmael will return to this topic in Chapters 74–80.
Revealingly, to Ahab the head looks more like a mysterious sphinx than a source of revenue. He wonders what secrets the head could tell since it has been where "unrecorded names and navies rust" and has "slept by many a sailor's side, where sleepless mothers would give their lives to lay them down." Ahab is a complicated man. His flaws and his virtues are huge. It would be a mistake to dismiss him or to try to categorize him simply.
