Bag of Three Winds

This ordinary bag, made from charcoal-coloured cloth, bulges with fluid contents like an air-filled bladder. It is tied with a firmly knotted rope, but can be undone with an action. The bag weighs 1/2 pound.

This bag has three charges. When you spend an action to untie the knot holding the bag closed, it expends a charge and releases one of its contained winds, casting the gust of wind in the direction of the bag's opening. This spell has a duration of 1 hour instead of 1 minute, and has a DC of 13. 

You can use the winds from this bag to propel a sailing ship, doubling its movement using sails for the duration of the spell. When the last of the charges is spent, the bag becomes nonmagical.