There's a huge "whale info dump," chapter that just goes on and on. Is this info given seriously, or is it supposed to be spewed in a pompous manner? In other words, is this part a sincere attempt to education/giving background info, or is Melville playing with us?
The larger question you're asking in the title of the post (did Melville mean to be funny) I think can easily be answered 'yes.' In his letters written at the time he was writing Moby-Dick he doesn't exactly come out and say that the book would be a real riot, but I'd argue it's fairly clear from the writing itself that many scenes are intentionally comic, not to mention the use of puns and often over-the-top absurd imagery.
From the first paragraph Ishmael talks about having to stop himself from taking out his anxiety by "involuntarily pausing before coffin warehouses" and "knocking people's hats off" in the street. The initial meeting with Queequeg, mediated by the landlord, is a classic slapstick, almost vaudevillian scene. The resolution, waking up in Queequeg's arms, seems to me almost like a Charlie Chaplin bit. Or take, for example, Chapter 95: The Cassock, which describes the job of the mincer boiling the pieces of blubber in the try pots while wearing the tanned skin of a whale penis. As Melville writes, the skin is taken off in one piece, turned inside out, with slits cut for the arms – a process invented, or at least greatly exaggerated, by Melville. "What a candidate for an archbishopric, what a lad for a Pope were this mincer!," he writes, making a pun obviously playing on the words archbishopric, prick, and comparing the mincer to the pope. This chapter is basically a 500-word dick joke.
But to be sure, early reviews of the book, i.e., reviews written by Melville's contemporaries, also recognized the book for its humor, particularly its satire. The London Morning Advertiser (October 24, 1851) noted Melville's "fertile fancy, ingenious construction, playful learning, and an unusual power of enchanting the interest." The Springfield, Massachusetts Republican (November 17, 1851) remarked on the book's "easy, rollicking freedom of language." A review in the New York Literary World (November 22, 1851) says the book "has its level passages, its humorous touches, its incident usually picturesque and occasionally sublime." Another in Harper's New Monthly Magazine (December 1851) writes that the first few chapters in particular "are pervaded with a fine vein of comic humor, and reveal a succession of portraitures.... through a good deal of perverse, intentional exaggeration."
Chapter 32: Cetology (the "whale info dump"), like most of the chapters describing whale anatomy and behavior, is similarly part educational, part comedy/satire. The conceit to use a bibliographic model of taxonomy itself is a jab at taxonomists in the mid-19th century who – without any direct experience with living whales – deigned to categorize them as they saw fit. But remember that in a pre-Darwinian world and without an understanding of evolution, prioritizing skeletal features over behaviors over habitats was, in many ways, just as arbitrary. Richard J. King, in his book Ahab's Rolling Sea: A Natural History of Moby-Dick, writes: "Ishmael from his barstool, or more appropriately his capstan above the forecastle, admits befuddlement. He argues, why not simply use size?" King also notes that this is also a time "when species were considered static and designed perfectly by God." So it's easy to see how Melville (through Ishmael) could look through all his books on whales and decide 'this is all nonsense' and come up with his own satirical taxonomic system. He was, after all, speaking from the vantage point of whalers, among the only people who had first-hand experience with whales and not just skeletons or terrible illustrations. Melville is also clearly satirizing the use of scientific names for whales (as opposed to whaler's many nicknames), writing that the sperm whale was the "Cachalot of the French, and the Pottsfich of the Germans, and the Macrocephalus of the Long Words."
Ultimately what I find puzzling myself is how people miss how funny the book is even in Cetology, often held up as the driest of chapters. He dismisses manatees from the conversation entirely: "I deny their credentials as whales; and have presented them with their passports to quit the Kingdom of Cetology." Of Narwhal tusks he suggests. "My own opinion is, that however this one-sided horn may really be used by the Narwhale—however that may be—it would certainly be very convenient to him for a folder in reading pamphlets." And the coloring of a mealy-mouthed porpoise: "The white comprises part of his head, and the whole of his mouth, which makes him look as if he had just escaped from a felonious visit to a meal-bag."
Are they all knee-slappers? Maybe not. But it's not hard to find Melville deliberately injecting humor into nearly every chapter, if not paragraph, seeming to understand that the material could get a bit dry at times. It also helps to read (and re-read) annotated versions of the book, which will point out dozens and dozens of other allusions and puns, illuminating the depth of the book's satirical references to other writers, scientists, and contemporary event. But much of the humor is self-evident, as most readers discover, and it'd be hard to believe that Melville wasn't in on the joke.
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