On the one hand, «Moby-Dick» is the story of the whales and the whalers. Information on this topic here is really an incredible amount. Only you need to treat it carefully and it is better not to take it on faith, as from the time of the writer’s life has changed a lot.
The most striking example is the fact that Herman Melville classifies whales to fish. Has changed and our relationship with whales to the modern reader many of the descriptions will seem just cruel, but still, I think you should do the discount at the time of writing.
On the other hand, «Moby-Dick» is not just the story of the flight and about the fate of one ship, the story of America nineteenth century is told between the lines. The author is not very optimistic about the fate of their country.
Chasing the Ghost evil, «Pequod», which is obsessed with his idea, he’s chasing death, which on all sides surrounds the ship and sends warnings. The finale is expected, it is referred to more near the beginning, but what the last Chapter is beautifully written