A photo and short description of a bomb-sighting instrument that was available to French and British pilots during the earliest days of World War One:
"One of the latest bomb-dropping devices which is being used on aerial war craft provides the flier with an accurate range finder. This increases the terror of the flying machine as a medium of human destruction, for it places in the hands of the aviator an instrument which allows him to place his bomb wherever he will."
Such instruments were seldom used during that war.
