Read "Nomad" by George O. Smith online for free on Textopian. Full text with search, annotations, highlights, and AI-powered reading aids.
Guy put the alien instrument in his personal locker and went to see how the battle was coming. Out across the face of Mephisto, he saw the battle machinery locked in mobile death with the huge, alien machines of Mephisto.
The ground was strewn with smoking ruin, and Guy saw with horrified gratification that the ruined machinery was all on the Terran side of the battleground -- which meant that his ring of offense was advancing. The energy bombs were bursting above the planethead, and the sky was filled with blinding light. Sub-ships fell as their drive was burned by the entrapped energy within the barriers, and Guy wondered how many men were getting energy burns from the terrific radiation from the energy bombs.