When France fell, a complicated anti-invasion system was brought Into force and has continued up to the prerent day. Sometimes pilots have Feported concentrations of barges. Often German conveys are seen creeping along the coast and bombers have followed up and sent many thousands of tons of German ship~ ping to the bottom, 'Then there is the offensive patrol in reconnaissance. 'This serves a double purpose; not only do aircraft jin such' work make reports but they also strike at once: these patrols have sunk many ships and scored direct hits on aerodromes and hangars.
Similat reconnaissances are constantly carried out over enemy territory and those occupied by the Nazis, Only trained observers can detect minute changes which have taken place between reconnaissance flights." 'Thus, a photograph which Jshows a few small white rings on the ground may' mean. that posts hav Been erected to carry cables for tele phones or electricity, which in turn Indicate the presence of large bodies Jof troops. Similarly, a certain loop on a railway may mean that a bat~ tery of the heaviest guns which*run Jon railway ines have been installed, There are many other signs which help estimate the number of troops any given area, Enemy aerodromes are regularly inspected and despite all. attempts at concealment, the number of air= craft on the ground can be count ed, In this way the movement of troops and aircraft from the west in preparation for the German offend sive against Russia was seen to have been well developed, 'AN the most important targets of the bomber command are photographed before and after bombing. Correct interpretation of the signs on photographs reveal whether plants are still working at near capacity land may be profitably bombed again or whether outputs have. slackened and another target should be chosen.
Text read from the printed page and cleaned; old type leaves the occasional error.