OSR Commentary - Original Dungeons & Dragons, The Great Wheel Cosmology, & The Dragon Issue #8

 When it comes to Original Dungeons & Dragons & the planes of existence there's one magazine that's critical and that's 'The Dragon' magazine issue #8. This blog entry is actually going to pick from our commentary on the Manual of the Planes here on the blog. 

And this is because of the Gary Gygax article "The Concepts of Spacial, Temporal and Physical Relationships in D&D" This is the first mention and definition of the familar 'Great Wheel'. And according to the Forgotten Realm Wiki entry on 'The Dragon issue #8 we get the gammit of planes;"

Locations

Planes: Astral Plane • Elemental Planes • Ethereal Plane • Inner Planes • Negative Energy Planes • Positive Energy Planes • Prime Material Plane • Outer Planes

Elemental Planes: Elemental Plane of Air • Elemental Plane of Earth • Elemental Plane of Fire • Elemental Plane of Water

Outer Planes: Abyss • Acheron • Arcadia • Elysium • Gehenna • Gladsheim • Hades • Happy Hunting Grounds • Limbo • Nine Hells • Nirvana • Olympus • Pandemonium • Seven Heavens • Tarterus • Twin Paradises" 

Mr.Gygax lays out the fundamentals right off the bat in The Concepts of Spacial, Temporal and Physical Relationships in D&D";
"For game purposes the DM is to assume the existence of an infinite number of co-existing planes. The normal plane for human-type life forms is the Prime Material Plane. A number of planes actually touch this one and are reached with relative ease. These planes are the Negative and Positive Material Planes, the Elemental Planes (air, earth, fire, water), the Etherial Plane (which co-exists in exactly the same space as the Prime Material Plane), and the Astral Plane (which warps the dimension we know as length [distance]). Typical higher planes are the Seven Heavens, the Twin Paradises, and Elysium. The plane of ultimate Law is Nirvana, while the plane of ultimate Chaos (entropy) is Limbo. Typical lower planes are the Nine Hells, Hades’ three glooms, and the 666 layers of the Abyss. Assume further that creatures which can be harmed only by weapons of a special metal (silver, cold iron, etc.) gain this relative invulnerability from having a portion of their existence in either the positive or negative material plane at the same time they exist partially in the prime. Therefore, those creatures which can be struck only with + 1 or greater magical weapons exist wholly and simultaneously in two planes (one of which is, of course, the Prime Material). So creatures which require attack of a + 2 or better magic weapon then exist in three planes simultaneously, and so on. This brings us to the consideration of the existence of magical weapons in other planes and in multiple planes simultaneously." 

And this goes back into original Dungeons & Dragons wargaming roots according to the same article;"As a side benefit of the use of this system, operation on the astral or ethereal by characters no longer poses such a headache to DMs. As magic weapons exist in those planes which touch upon the Prime Material Plane, any person armed with a magic weapon will be able to attack into the Astral or Ethereal Plane if they become aware that their opponent is operating in one of these planes. Finally, what of magic swords of special nature or special purpose which are far removed from the Prime Material Plane? I suggest that these weapons can be removed no further than the number of planes from the Prime Material which equals their best bonus stated as a “to hit”, i.e. a + 2 can be removed by two planes and still retain its magical properties. Certain swords will have special treatment — the sword of sharpness and the vorpal blade most notably. On the other hand, a sword of life draining ability gains no such consideration, for it operates primarily on the Negative Material Plane. In any event, swords removed beyond the plane limit given will lose all of their magic, becoming nothing more than normal weapons. This same “law” can apply equally to those weapons, swords or otherwise, which have a simple “to hit” bonus." " And below is the 'Great Wheel' and yes it's from Kuntz and Ward's Gods & Demigods for AD&D first edition but it's very easy to read.  You can read about the Great Wheel cosmology here for even more clearity. 

What the Gary Gygax article "The Concepts of Spacial, Temporal and Physical Relationships in D&D" is doing is simultaniously setting up planar travel for original Dungeons & Dragons. And this article is also laying the groundwork for planar travel to be a high level occurance in Advanced Dungeons & Dragons coming up. 
Everything in the Gary Gygax article "The Concepts of Spacial, Temporal and Physical Relationships in D&D" is layed out and colour coded. Is it easy to use? Yes and no, if the DM wants to do some of the work of getting the planes into his or her original Dungeons & Dragons game. The ground work is right there.