“In life, the visible surface of the Sperm Whale is not the least among the many marvels he presents. Almost invariably it is all over obliquely crossed and re-crossed with numberless straight marks in thick array, something like those in the finest Italian line engravings. But these marks do not seem to be impressed upon the isinglass substance above mentioned, but seem to be seen through it, as if they were engraved upon the body itself.”
Moby-Dick, Chapter 68, “The Blanket”
The “finest Italian line engravings” of which Melville writes is intaglio, meaning a printing process that involves the etching or engraving of a copper plate. Through this description, Melville is either suggesting that the whale is like an engraved plate or is like the printed image from that plate, an ambiguity that supports the idea that the whale itself is as an enigmatic text. An exmaple of an intaglio print may be see in the above book, Abrégé de l'Histoire Générale Des Voyages.
Image: T. H. Fielding 's Art of Engraving (London, 1844) illustrating the act of engraving and intaglio plate