Hidden Treasure?

I was reading the Wiki while doing a dungeon, and I came across a mention of "Hidden Treasure" at the bottom of the wiki. I spent alot of time searching the specified areas, and indeed, searched the entire 3rd level. How do I activate these switches? I am a bit confused.

http://wiki.guildwars.com/wiki/Bloodstone_Caves

Any help would be appreciated. Thank you.

Pretty sure you use light of deldrimor.

http://wiki.guildwars.com/wiki/Light_of_Deldrimor

Use Light of Deldrimor. If there is a chest within radar map it will "ping". Get close and use LoD again to reveal chest. Collect your 100 to 150 gold (WHOOPEE!) and move on. LoD can also be used to discover Dwarven Ghosts, which are like extra henchies (only better) on your team.

Oh. I get it now. Don't know how I didn't understand before. It seems obvious.

Thanks for the help.