Guybrush is in a foul mood because he's just fallen over the cliff. As he pick himself up, make sure that he also grabs the prying tool lying somewhere in the rubble of the artifact altar. As he makes his way back to the entrance, Le Chuck appears and hands him the turtle artifact. With two of three artifacts in hand, Threepwood now heads to Roe Island in search of De Cava in order to return his locket.

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Proceed to Roe Island where you will find De Cava's ramshackle of a place. Scattered everywhere are empty crog bottles, sketches of the Voodoo Lady and a cot that's filled with seagull dropping. Items to take note of however, are the stuff on the wall. One is a hanged Manatee, and a diagram of the mouth (Remember the path and the mouth thing the Vacaylian chieftain was talking about? This could be it).
Anyhow, remember that locket that you have with you? Place it where you can find a hole in the whole (where the manataee is) and it will reveal a blank piece of paper. Don't worry, this doesn't mean that we've just wasted our time, but that we've found a secret message from de Cava himself. So what we need to do now is access our inventory and place the eye of the manatee on the Examine slot, and place the glass eye from the statue earlier in the examine slot as well. Combining these two items together sort of makes the Eye of the Manatee into a magnifying secret message finder.
Once you've combined the Eye of the Manatee together with the glass eye, its time to use it on the blank piece of paper we found at De Cava's shack. The message will say, 101 Fish Jokes. Is that a book of jokes of some sort? Where could we find a library at Spinner Cay? Hmm... I'm sure you've figured this out by now.