There are solutions at the related questions below.
its in the museum on mainstreet of steamworks island :)
It's Steamworks Island #14th Island
(The solution is at the related question "How do you beat Steamworks Island")
by spinning the circle around and getting the ball in the middle whole each time
the crab on steamworks island is next to the living quarters
You go to Steamworks and head to the museum and there is the Deogen
steamworks island
There is a video walkthrough at the related link below. There are written WikiAnswers solutions at the related questions, as there are for all Poptropica islands. (How do you beat Steamworks Island) (What is the walkthrough for Steamworks Island)
Steamworks island
Steamworks island is an island with huge metal edifices, and lots of complex machinery, much of it in disrepair or overgrown by huge plants. There are no signs of the people who built the machinery. You have to explore the island to find out where everyone has gone, and why. With the help of a friendly robot, find the working machines and solve the mechanical challenges, then charge into action against the monstrous creatures who have taken over the island.
how to do the bridge terminal on poptropica's steamworks island
you can get it on the far left of steamworks island, past the living headquarters.