On Mon, 18 Aug 2008 03:51:38 GMT, Buzzihd Beah
wrote:

Two weeks later, we were drifting along Buzzards Bay channel, and the
anchor and the chain and the shackle fell off. They just fell off, and
went to the bottom, and I don't know why.

Unless the screw pin of the shackle has been secured with safety wire
or a nylon wire tie, the pin will work itself loose from wave action
and vibration.