Do the following series of fetch-quests to get the Hurricane Spin ability:

1.) Go to the traveler's ship in the northeast section of the sea. Defeat the monsters you find there, and you will receive New Hero's Clothes, as well as a Treasure Map.

2.) Take the clothes to another traveler's ship, this one in the northwest section of the sea, and give them to the man there. He will give you the Kaleidoscope in return.

3.) Take your newfound Kaleidoscope to the traveler's ship in the southeast section of the sea and give it to the man in want of a telescope. He will give you the Guard's Notebook in return.

4.) Take this notebook to the traveler's ship in the southwest section of the sea and give it to the man you find there to acquire the Wood Heart.

5.) Finally, take the Wood Heart to the Old Wayfarer's Ship, and he will give you the scroll which will allow you to learn this technique!