I am stuck in The mine car level.I have collected all the gems to open the temple door except the one where you swim into the room with the Z shaped pool. All the walkthroughs say you climb the pillars, however I can only jump across the pool to the first pillar. From them on I'm stuck. The other pillars seem too high for indy to jump up too.What am i doing wrong????

Have you seen the bazooka cut-scene already, that is where one of the commies fire a hole into the trails and Indy's car jumps over it? If not, return to the swich house and pull the lever for switch #3. On your next round this will trigger the bazooka cut-scene so you can reach the green gem.