BP, scientists try to make sense of well puzzle

Engineers kept vigil Saturday over the massive cap holding back oil from BP's busted Gulf well, their eyes glued to monitors in a faraway control room that displayed pressure readings, temperature gauges and underwater images.

Their round-the-clock work deciphering a puzzle of data from undersea robots and instruments at the wellhead is helping BP and the government determine whether the cap is holding tight as the end of a critical 48-hour testing window approaches. Signs so far have been promising but inconclusive.

Saturday afternoon will mark two full days since BP stopped the oil from leaking into the Gulf and entered into the pressure-testing phase. At …