I thought this article was interesting. There are some beautiful illustrations. Looking at the comparative sizes between the whale, the whaleboat and the main ship gives me pause. How terrifying and thrilling the job of the whalemen must have been! Imagine the adrenaline rush during the hunt.
How realistic are the vengeful whales of “Moby-Dick” and “In the Heart of the Sea,” really?
http://qz.com/572252/how-realistic-a...he-sea-really/
Here's a link that explains more about the legend of Mocha Dick.
https://en.wikipedia.org/wiki/Mocha_Dick