Make your way back down to ground level in this chamber and head through the gate in front of you. Run through the tunnel and jump onto the wooden beams in front of you. Jump and swing across the chamber through the smoke to the exit of the chamber. Otherwise you need to deal with the guards below you.
Head through the tunnel to the next chamber. Use Eagle Vision to see the guards. Head over to the left. Climb the wooden pillar there to the top. Go over to the left and jump for the rope to get to the next highest beams. Go to the middle of the next wooden beam and jump toward the lantern. Follow this tunnel to the left and then run and slide underneath the rubble. This will complete the memory.