how to turn on empty iPad while loading? How do I turn on an iPad (first revision) during it is loading. Or how do I turn it on at all?

When I plug it in, the display shows a battery symbol with a little bit of red juice on the left side (seems to be empty). Then the display turns off after a few seconds.
All iOS devices do that after they have been completely discharged.

If it does not boot up with in 5-10 minutes of being plugged in, then it could be an indication of hardware failure. The battery is likely not accepting a charge.