Back at the five-way intersection, go hard right (or southwest). This is the house. Go behind the house and right to go into the garden. From the lady that's weeding, go straight left and take your first right into the tiny fountain area. You'll find a key here. Go back to the ladder by the house to activate it. Climb the ladder into the attic.

Upstairs, go left. There's a light here. Activate it for Momo to show up. He'll give you a piece of paper and a pen, he wants a mammoth. First go behind him and open the desk - get Anna's diary and some ink. Now go back to the light, and look to the right of it. There's a mammoth drawing on the wall behind it in white. Use the paper on it to get a rubbing of a mammoth. Give this to Momo and he'll take off to the cave. In essence he's going past the notary's house to the grate-fence further down that road, so just head there. He'll keep stopping to wait for you.

Syberia Walkthrough, Tips and Techniques