Tremors from the Fed's Grand Experiment

Ben S. Bernanke and the Federal Reserve have been conducting a gigantic monetary experiment aimed at reducing unemployment, speeding up the economy and reviving the housing market.

Using traditional methods, as well as some that have never been tried on so large a scale, the Fed managed to nudge down a broad range of interest rates to extraordinarily low levels for a very long time. But earlier this month, Mr. Bernanke indicated that the time for winding down the grand experiment might be growing closer.