Alas, despite the fact that all the descriptions speak of placing the
fingers "on" the stone, the picture he publishes shows everyone underneath
it.
There still may be something other than simple division of weight at work,
however, because I can't imagine 11 people all exerting an equal amount of
force while crowded around the stone. In fact, in the picture there hardly
seems to be 9 people near enough to touch it, let alone 11, and they're
certainly not symmetrically spaced because there's a large gap on the side
toward the photographer! I just can't see how you could, under those
conditions, keep your finger (not thumb, unless they've changed the ritual)
rigid enough to lift it, unlike the party levitation trick in which I could
easily imagine locking your finger into someone's armpit or under their
knee, and putting all the weight down toward the knuckle instead of on the
tip. I can scan the photo and sent it to Jerry if he wants it, but I'm not
sure whether I'll be able to flatten the book enough to get a good scan,
especially as I only have a handheld scanner.