I remember reading that he had suffered a hand injury, and this greatly hampered his ability to play guitar in the conventional manner, so he went to playing mostly slide instead. On one of their albums, a band member (or Lowell?) is heard talking about using a Craftsman 7/16" socket wrench.
Probably George. A deep socket (spark plug) would make a perfect bottleneck. My main gripe about the slide guitar is that eventually everybody starts to sound like Duane Allman or Elmore James.
