A squad broke into the ancient R.C.A. buildings, abandoned and sealed up for two generations. They went down into the cellar arcades, crumbling museums of the retail stores of centuries past. They located the ancient elevator shafts and dropped through them into the subcellars filled with electric installations, heat plants and refrigeration systems. They went down into the sump cellars, waist deep in water from the streams of prehistoric Manhattan Island, streams that still flowed beneath the streets that covered them.