In this level, you will come to a cave entrance with spiders surrounding a tree 
stump to the left. Ignore it for now, but this is the location of one lever. 
After you defeat the Raptors (kill them with flaming spears), light a spear on 
fire and burn the brush to the left of the gate while facing it. This will 
unveil the second lever. Grab a spear or bone, stab a dragon fly, then go back 
through the cave where the spiders were. Throw the bait to the right so the 
spiders leave the tree stump and you can obtain the other lever.