The north-west or south-west is a waterproof hat with a large brim back, used by mariners. Typically the sailors would use it to the deck of fishing vessels. In the nineteenth century it was used by harpooneers whaling and was called southwest. Made of waterproof waxed canvas waxed like that is a complement.

In the literature there is mention of this headgear work in Moby Dick by Herman Melville. In the first chapters the main character runs into a man dressed in a south-west to the streets of New Bedford

from Wikipedia (5 years and 2876 days ago)