Stubb and Flask talk briefly of how strange it is that Ahab has his own whale-boat under his command. It is not common for the captain of an entire whaling vessel to have his own whale-boat, since the pursuit is so dangerous. And Ahab, having only one leg, will have a harder time than most maintaining balance in the whale-boat, since it rocks a great deal, and can cause even very able men with two legs to stumble.
Typically, the captain would stay on the vessel while the three mates would be sent into the water, in command of their own boats. This conversation prefigures how that typical arrangement will be overturned in the final chase of Moby Dick near the end of the book—Starbuck will be put in charge of the Pequod, while Ahab takes out his boat into the deep.
Ishmael also writes, briefly, that Fedallah and the others of the “tiger crew” do not ever really mingle with the remainder of the boat, and some among the sailors seem to think that this crew possesses a demonic quality. A bit of this is attributable to the Pequod’s distrust of sailors from Asia, as they think that men from that region are not to be trusted, and are indeed descended from devious characters from long ago—at least, so run the rumors among the American sailors of the Pequod.
An instance of racism against the peoples of the Far East. The crew of the Pequod believes that Asian cultures are inherently mysterious, secretive, and perhaps even engaged in activities that seem devilish or idolatrous to followers of the Christian faith. Thus, the crew’s racist attitudes amplify the already-strange environment aboard the ship after the revelation of this “tiger crew.”