Need help in advanced chamber 15.

[Fluff]

I got to the second time where you have to fling yourself over a glass wall below a material emancipation grid and I was able to use the portal's travel time to get a segnificant amount of vertical momentum by the wall via two portals next to each other but the gap between the portal area and the glass is too wide and I can't getover it with this alone. Is there a good source of horizontal momentum in the room I could use to get over it? (Or, of course, another solution.)

[_Soj_]

That one is tricky.

Hint:

1. Put an exit portal as close to the barrier as you can, then go over to the side area and fire an entry portal into the ceiling above the portal-enabled floor.

2. Go back and fall thru your exit portal, then quickly fire a new entry portal into the floor.

3. Now that you have momentum, press the appropriate movement key as you come up thru the exit portal so as to propel you in the right direction over the barrier...

Just keep trying and eventually you'll get it.

[Green Goblin]

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