The child is little negro Pip with his tambourine [little hand-drum rattle]. He represents the vulnerable primitives who fall under the thumbs of enslaving, technologically superior whites. Melville is kind in his description of such blacks in general and of Pip in particular:
"Pip, though over tenderhearted, was at bottom very bright, with that pleasant, genial, jolly brightness peculiar to his tribe -- a tribe, which ever enjoys all holidays and festivities with finer, freer relish than any other race. But Pip loved life, and all life's peaceable securities. But the panic-striking business in which he had somehow become entrapped had most sadly blurred his brightness."
With this characterization we realize that if Melville had spent less space on characterizing whales, he would have been able to develop Pip as a character in the conventional way -- through conversation, interactions, and narrative treatment -- something he had left little time or space for. We must be satisfied with Pip as a very sketchily drawn figure, albeit one who is chosen to be at the center of a "significant event", and in consequence became the "living and ever-accompanying prophecy of whatever shattered sequel" was in store for the Pequod and her crew. This ship, named for another primitive tribe that went the way of all flesh in their clash with technological superiority, is being captained by the likes of Ahab, and crewed by the likes of Stubb to perdition.
It seems that Pip is required to take the place of an oarsman in Stubb's whaleboat -- a job for which Pip had no qualification. The first time a whale is struck, poor Pip jumps out of the boat and gets tangled in the whaleline, which has to be cut -- saving Pip but losing the whale. "Stick to the boat, Pip, or by the Lord, I won't pick you up if you jump. Mind that," warned exasperated Stubb. "We can't afford to lose whales by the likes of you. [Here it comes . . .] a whale would sell for thirty times what you would, Pip, in Alabama." [Black boys and whales have their price in the world of the Yankee whaler. Melville's comment is that man is a money-making animal, "which propensity too often interferes with his benevolence."]
"But we are all in the hands of the Gods; and Pip jumped again." True to his word, Stubb left Pip floundering in the water as his boat was towed off by a whale. The other boats were not in position to spot him, so poor Pip was left for drowning -- "another lonely castaway, though the loftiest and the brightest." Something snapped in the innocent, trusting soul of little Pip, as he resigned himself to his lonely fate. Then . . . "By merest chance [there it is again] the ship itself at last rescued him; but from that hour the little negro went about the deck an idiot; such, at least they said he was. The sea had jeeringly kept his finite body up, but drowned the infinite of his soul [and there that is again]. Not drowned entirely, though. Rather carried down alive to wondrous depths. He saw God's foot upon the treadle of the loom, and spoke it; and therefore his shipmates called him mad."
Ishmael then tells us that he, too, will suffer abandonment in due narrative course.