Geirfast has identified the small cave described in the map and will send the wondrous torch you have assembled to it while you find an ally or two.
'You have collected all the materials, and I have assembled the torch this map calls for -- now it is time to see what we shall do with it!
'A lit torch is a fit weapon against few creatures; I suggest you find an ally, perhaps two, in case you have to move around while the torch is lit. While you are looking for the help, I will just send a runner to bring the unlit torch into the cave described in the map.
'Speak to me again once you are ready to leave.'
Geirfast is in the Twenty-first Hall.
You should speak with Geirfast again when you are prepared to travel to the strange cave.
Geirfast is at the Twenty-first Hall.
You should return to Geirfast and tell him of the strange map you saw projected on the wall by the light of the torch.