In the Time and Tide area, how can I go right on the procedurally dropping floors

legend-of-grimrock

On level four, through the Time and Tide portal, how do I go right when I have to move across the long open/shut floor thing? Do I just have to be fast and run over there before those re-open? I've been trying that, and it doesn't seem to be working.
Looking back and to the right at where I might want to go
Map location
Looking at the map, it seems to just be a 1×1 room. What's over there?

Best Answer

There is a hidden switch in the right hand wall as you start going down the collapsing hallway, which slides open a section of wall a bit further ahead on the right, letting you get back there and grab the Chitin Mask from a wall nook.

I don't remember the exact square which has the switch, but as you start going down the collapsing hallway, it'll be a loose rock in the wall on your right. I've marked roughly where I think it is on the map (I might be off by a square), as well as marking the wall section which slides open and where the mask is contained.

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