When you have returned all the items to their proper times, the dial of the time device should be all green and the "Lab" will flash (12 o'clock). Select that and go back through the Future Machine in Pendulum's lab. After you find your Future Self and get the Island Medallion, repeat the process (return to the Lab) to leave the island.
After the Future Machine's plug is pushed in, you click to enter it and travel to the future.
When you return an item on Time Tangled Island, the time device shows "green" for that time (there may still be objects to come from there). When all times are green, travel to the Lab (12 o'clock. the present). Use the Future Machine to travel to the restored future and get you Island Medallion.
After you travel back to the future to get the Island Medallion, return to the present to leave the island (just as you did after completing the items), by using the Lab selection on the time device.
Return all 11 objects to their proper time periods, then travel into the restored future, again using the Future Machine at Pendulum's Lab. Climb to your sky home and get the Island Medallion from your future self. (for the full solution, see the related questions below)
When you use Professor Pendulum's "Future Machine" in the Lab, you travel 50 years into the future. The first time you do, you get the time travel device (stopwatch). The second time, when the items have all been returned and the time device is all green, takes you to the "restored" future and you receive your Island Medallion.
There isn't a battery. You might be referring to the time travel device (stopwatch). You get it by going to the lab and plugging in the Future Machine to go to the future. Your future self (50 years from now) will give it to you. (see related question)
You use the Future Machine in Professor Pendulum's Lab to travel to the future, The first time you get your time device from your future self. The second time, once you have restored all 11 of the items (time device is all green), you will receive the Island Medallion from "yourself" at your skyscraper "sky home". (see related question)
It is on Time Tangled Island. You will get to it when you retrieve the golden stopwatch to travel in time.
Use the time device at the 12 o'clock setting (lab) and it will take you to the outside of Pendulum's lab on Main Street. This is also what you do when all of the items have been returned, so that you can use the Future machine to travel to the future again, and receive the Island Medallion.
The older You is still in the Future, but it is no longer bleak and desolate. Once you have returned the 11 items to their proper time period, the Time Device will be all green and the Lab (12 o'clock) will flash. Use the Lab setting to return to Professor Pendulum's lab on Main Street, and power up the Future Machine again to travel to the restored future. Take the hovertrains (ride their exhausts) to your Sky Home and receive the Island Medallion from your future self. (Leave the island by using the Lab setting again to get back to Main Street.)
the stone bowl(anyway,its time tangled)
To find all the artifacts in Time Tangled Island on Poptropica, you will need to travel to different time periods using the time machine. Each time period has a specific artifact that you need to locate and return to the future. Pay attention to the clues given in each time period to help you locate the artifacts.