Where do you find the torture rack on Zynga pirates?

POSEIDON'S CHEST
3 Locks - Jolly Roger Flag 18/18 Item
4 Locks - Octopus 18/18 Item
5 Locks - Boatswain's pipe - 20/20 Item
6 Locks - Exploding Cannonballs 22/22 Item
7 Locks - Wolfs Head Cannon 24/24 Item
8 Locks - Shrunken Heads 25/25 Item
9 Locks - Scoripo 26/26 Item
10 Locks - Torture rack 28/28 Item