Part 72: Bonus Update 38.5: Great Eastern TowerBonus Update 38.5: Great Eastern Tower
The vote was looking close at first, but then a bunch of votes for outdoor exploration sealed it: next time, the party will be doing their best Moses impressions and wandering in the desert (hopefully not for 40 years).
As you saw this update, the hintbook's information about the Book of Great Power removing Thievery is wrong, at least for the Mac version; I can't speak for other releases of the game. I'm not 100% sure whether Druids can read the Book of Fantastic Knowledge or not: the hintbook doesn't say they can, but logically they should be able to if Rangers can. You shouldn't be using a Druid anyway, so it's a moot point.
I disagree with the hintbook about the Great Eastern Tower being the hardest one to complete. Apart from the easily skippable Gamma Gazer at the top, I usually find the Great Northern Tower harder.
It does have the most complicated layout of any tower, though. Take the northernmost staircase on the ground floor to reach the area containing the Jewel of Ages; most of the other passages just lead to monsters.
See you in the Desert of Doom!