How do you operate the time machine on Time Tangled Island?

The Time Travel Device (pocket watch at the bottom-left of the screen) Just click on it, select the time you want to be in (the Mayan head for the Mayans, the viking head for the vikings, etc.) and wait until the needle stops spinning. Then push the green button on the left of the watch. Once you have completed the mission in that time, then that slice of the watch face will turn green. The Future Machine (in the Lab, 2009) Go to the bottom of the room and push the battery until it locks in. Then go through the door with the FUTURE sign over it.