This is how you fix the time line in pendulum's lab:
You return all the things to their owners. Each object is in a different place in the
time travel. I'll tell you where one is, though. For the one where one of the climbers
at Mount Everest lost their climbing goggles, you need to go to the Aztec Empire
and get one of those Aztec masks from the old lady standing on one of the pyramids.
If you put it on, the guards will think you are Aztec. Click on one of the guards and
they will give you the climbing goggles.
Hope this answer helps you.
Natalie