Children's Tales by Laura Hale

Dr Satan was a short story series in the 1930s pulp Weird Tales. Here rich millionaire Ascott Keane and his resourceful secretary Beatrice Dale fight the machinations of Dr. Satan who is out after money and power using weird science. In this case The Blue Bay Development Company is being threaten by the bad Doctor. Everything looks black until Ascott Keane is called in to solve the puzzle.