I bought Sign of the Labrys because it's on the Appendix N reading list, and because Mike Mornard recommended that I read it to understand where the D&D "dungeon" came from. Its bizarre 1960's back-cover blurb was icing on the cake:
This blurb merits further discussion, but right now, I want to talk about dungeon levels.
Pages one through 19 of Sign of the Labrys are fairly ordinary post-apocalyptic science fiction. Then on page 20, Margaret St. Clair gets down to business and explains exactly how dungeons work in D&D:
It is important to understand what a level is. It is not much like a floor in an office building. A level may be a hundred or a hundred and fifty feet deep, and subdivided into several tiers. Also, access to them is not uniform. The upper levels are simple and straightforward; one gets to and from them by stairs, escalators, or elevators. [...] But the upper levels are easy. As one goes down, it gets difficult. Entrances and exits are usually concealed.
It is interesting to note that just going down a set of stairs doesn't guarantee that you're going into a deeper "level": a complex that's 150 feet deep, and composed of several tiers, can be considered a single level if it's part of the same ecosystem. And that is, I think, how early dungeons were designed. Each level was its own conceptual unit: it might or might not be composed of several floors.
The author goes on to explain something else puzzling about Gygaxian dungeon design: levels aren't always stacked one above another.
F had been designed as the laboratory level, but there had been a foul-up in its construction. F1 and F2, the partial levels, or tiers, which had been meant to house the lab workers of F, had been constructed above it and on the bias, like the two arms of a Y.
Compare that to a side view of a dungeon from OD&D's Underworld and Wilderness Adventures:
It's important to Gygax that the dungeon levels have the same sort of complex relationships to each other that they do in the above St. Clair quote. Look at levels 4a and 4b, above level 5 like the two arms of a Y.
James Mal, ever a careful OD&D scholar, makes sure to do something similar in his Dwimmermount megadungeon: level 1 has two stairs down, leading to levels 2A and 2B. Who knows if Dwimmermount would be designed thus if there had not been a "foulup in the construction" of Level F in Sign of the Labrys!
High five, guys! We squeezed a lot of D&D out of that single page. But page 20's bounties are not yet exhausted. Here's some prototypical dungeon exploration, still on page 20 (and running to page 21):
The corridor was narrow and high. It ran straight for six or eight feet, and then seemed to descend a couple of steps... I walked along the corridor to where it changed level... the space in front of me was large, perhaps twenty by fifty feet, and it was carpeted with a dense deep covering of shining white... the space before me, from wall to wall, was filled with white rats.
Change the first person past tense to present second, and you have something that sounds a lot like a DM's monologue, even down to the obsession with measurements. So much, in fact, that I stole this room and put it into Dwimmermount when I ran the Lawful Evil event - along with a sinister glowing gem that turned people into rats. The party members, Lawful Evil as they were, went to great lengths to convince other characters to touch the gem.
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