These were the machines which flew over England and France in 1917 scattering death and destruction. Against them the machines of the Allies were for a time almost powerless, for the best of their airplanes were completely outgunned by this new terror of the skies. The new German machine was given one of its first tryouts in the Balkans, where a squadron of twin-engined _Gothas_ accomplished the bombing of Bucharest. Its efficiency proved, it appeared over the lines and was also used extensively by the Germans for long distance bombing operations. The fact that the _Gothas_ flew in large squadrons made them still more difficult to attack. Yet Allied airplanes went out to give them fight, and in spite of what seemed the almost complete hopelessness of the situation, they did succeed in breaking up _Gotha_ formations and in downing a few of the dread machines. Yet another German twin-winged bombing plane was ready about this time. The _Friedrichshafen_ bomber was not so large as the _Gotha_, but in many points of construction it resembled it. A biplane, it had wings that tapered somewhat from the center to the tips. The wings were strengthened by center spars of steel tubing, which was also used in the construction of the rudder and elevators at the tail. The pilot occupied the rear seat in the cockpit and the gunner the forward seat, while a short passage-way ran between the two. Every effort had been made at camouflage. On their upper surfaces the wings were painted as nearly as possible earth color, so that they might be indistinguishable to a machine looking down upon them from a superior altitude. On their lower surfaces they were painted pale blue, to blend with the sky and make them invisible to an enemy plane below. The armament of this _Friedrichshafen_ bomber consisted of three machine guns, one of them firing downward through a trap door in the fuselage. It was fitted with an automatic bomb-releasing apparatus, by means of which, as one bomb was released, another slipped into place. Other bombing machines appeared in 1917, as the _A.E.G._ twin-motored tractor biplane, and the _A.G.O._ twin-bodied biplane. The Germans also began construction of huge bombing triplanes, heavily armed with machine guns. With squadrons of these, the _Gothas_, and the _Friedrichshafens_, they carried out in 1917 and 1918 an established program of bombardment. The night no longer held terrors for their airmen, who had learned to fly in the darkness. They made their raiding expeditions, not only against Allied troops and military bases, but also on English and French towns, killing civilians and children and destroying property of no importance from a military point of view.