 If insects were the answer, there should be some kind of evidence of them right here in the area where Ethel was lying. Certainly, one or two of them would be crushed when she rolled over in her sleep. Well, that sounds reasonable. Now, look for yourself. There's absolutely no sign of anything at all here. Well, what about some chemical, some vapor oozing from the ground? No chance at all. I'd rule that out completely. Then what? Well, there's the tree itself. I suppose it could exude some sort of a chemical that might dissolve cloth, but...