OD&D Spell Adjudications

One of the wonderful things about OD&D is the bare-bones descriptions of spells and magic items. Generally they are very common-sensical, before the language had to be expanded or tightened up to handle loophole cases or unexpected behavior. When I read them in this state, it's a lot easier to visualize fantasy-sensible rulings on spells I've had problems with before. Here's two examples:

- Transmute Rock to Mud. The problem with this 5th-level spell is it can frequently be taken to instantly reduce any castle or dungeon complex to quivering mud (i.e., for the campaign world it makes the entire technology and political usage of castles totally useless). But the origin is clear: it comes from the mass battle rules, intended to make a large area hard to pass for troops, and was never created thinking about fortifications or enclosed spaces.

So my ruling in this case would be to simply state that it can only be used to make a "mud pit", lying on top of a generally horizontal surface, as originally intended. Trying to use it on load-bearing, free-standing, or vertical structures (castle or dungeon walls) causes the spell to fail.

- Silence, 15' Radius. Added in Supplement I: Greyhawk, this is another problematic spell, in that it can instantly shut down opposing spellcasters -- not just by being cast at them, but by any thief, fighter, or thrown stone with the spell on it getting in range of effect. Also, it's just odd from a flavor aspect that clerics can make this radiating sound-cancelling aura, which to my knowledge has no analog in standard fantasy or myth. Strange.

But reading it in OD&D, the intention seems pretty clear. The language is practically the same as something like invisibility 10' radius or haste or slow. That is, I would rule that the silence spell effects specific individual objects or creatures -- you can cast it on several bodies within 15', which are then individually quieted. They don't radiate an aura of silence from that point forward; they are simply themselves quieted for the purposes of movement and surprise, much like elven boots or the like (in fact, I'd still allow normal speech and spellcasting if so desired). To me, that makes infinitely more sense as a divine magic effect.