The Croft Manor (part 10)
Tomb Raider Anniversary Game Guide and Walkthrough
Get back down. Grab the box marked with red, and pull it onto the trigger.
It will hold open the secret place with the arrow behind the fire.
Use the water bucket on the fire to extinguish it.
Grab the decorative arrow.
Go back to the gardens, and to those statues in the middle of the maze.
Use the decorative bow on the statue, and then the arrow. Stand on the designated side of the statue to do this. (The picture is messed up but take my word for it, it's the bow).
..and arrow
Use the gear on the opened panel.
Just pull the lever.
Get the fallen musical box.