No sooner had he spoken, than both boys were at their stations.  The next moment a great white path, widening as it went, streamed out into the darkness, lighting up everything in its reach with the brilliancy of day, but with a bluish-whiteness which must have been decidedly terrifying to the superstitious negroes.  Like an accusing finger the strange light swept around the field, raising and lowering, resting a few moments on this group and then that group of petrified, hideously-painted faces, from which eyeballs stood out like knobs of white marble.