Grimrock

I'm having severe trouble with the hallway/room starting off next to the source of the single lightning conduit in the long hallway in level 8.
I watched the only playthrough and all threads I could find on this particular spot, and found my reassessment (in the spoilers) correct; however no one goes into detail on how to open the passage right next to the lightning conduit, and I couldn't detect any visible mechanisms on opening it in the playthrough I watched. It seems almost as though it's open by default, but that can't be the case since it's closed to me. Would anyone be so kind as to tell me what I'm missing here?

If I remember correctly, you can't enter the Vault from the regular stairs that are used for going down. You need to find the other stairs on lvl 7.

Cronicler wrote:If I remember correctly, you can't enter the Vault from the regular stairs that are used for going down. You need to find the other stairs on lvl 7.

Sorry, but I'm afraid you misunderstood my problem completely. I'm talking about the room located next to the single lightning conduit next to the lightning trap at the very end of the hallway with the runic text "Lightning conduit" engraved outside the entrance (an iron gate opening with a lever, opening which will extend the flying path of the lightning bolts for another 3 or 4 blocks). I've found every secret in levels 7 and 8 and got the dismantler, only this one room containing the gear key isn't working out for me.

EDIT: So, for further and final clarification: The lightning conduit in question isn't anyhow related to the lightning traps in and in front of the dismantler's vault.

Ah sorry, my mistake.

The south-east room of that passage has a switch that opens up another wall into the corridor. 1 tile west of that (I think) hidden door, there is another secret switch on the north wall of the lightning conduit corridor.

That's the switch you want.

Thanks, seeing it now I'm finding it hard to believe I spent over 2 hours not finding that.