Geri,
If you are by the Ram stone, you are at the other end of the island.
Best to go back to a saved game after talking to Holmes in the hole.
Then do a 180 turn. Walk towards the lighthouse with the water on your right.
Keep looking for the log on the ground as you go.
After picking it up, do another 180 turn, keep the water on your left and look for the hole where Holmes is located.