It was the bombing plane, however, that appealed most strongly to the German mind as an instrument of destruction. Tired, perhaps, of their efforts to produce a fighting machine which should be without its match in aerial warfare, they focussed their attention about this time upon the bomber, which in 1917 was playing an ever more important role in the struggle for air supremacy. Early in 1917, the flower of their creative genius took to the air. It was the _Gotha_ biplane, and at the time of its début it proved one of the most difficult machines to attack and down of any of those flying for the Hun. The _Gun-tunnel Gotha_ it was familiarly called, owing to the unusual means of defense against pursuers that had been devised for it. Up to this time one of the best methods of attacking an enemy plane had been to come up suddenly and fire on it "under its tail." The gunner in the machine thus attacked could not get in a single shot at his pursuer without striking the tail planes of his own machine. The portion of an airplane which can be fired on in this way without danger of return fire is said to be its "blind spot," and it was this blind spot that sent many a well-armed and powerful airplane crashing to earth when its pursuers had succeeded in outmaneuvering it. The _Gun-tunnel Gotha_ had practically no blind spot. Its designers had constructed it with a tunnel that ran the length of the fuselage, from the cockpit, or compartment where the pilot and gunners sat, through to an opening just under the tail planes. A machine gun in the cockpit could be pointed through this tunnel and fired at the unsuspecting victim who came up back of it according to the most approved tactics. The opening of the gun tunnel was carefully "camouflaged," so that at a short distance it could not be seen by an attacking airplane, especially one which was unprepared for it. The _Gotha_ practically bristled with machine guns. One in its bow which commanded a fairly large range was operated by the forward observer, who sat in front of the pilot. A passage-way beside the pilot's seat allowed him to reach "gun-tunnel," where, stretched flat on the floor of the fuselage he operated the gun which fired out under the tail. Above him in the fuselage sat the rear gunner, and by their combined aid the _Gotha_ could keep all enemy planes at a safe distance. [Illustration: _Copyright Underwood and Underwood_ A GIANT GOTHA BOMBING PLANE BROUGHT DOWN BY THE FRENCH] These, however, were merely protective measures. The Gotha's real mission was bombing, and for this it carried a bomb-releasing mechanism just in front of the pilot's seat, on the floor of the fuselage, while behind the pilot an additional supply of the death-dealing missiles were carried in racks in vertical position. [Illustration: _Copyright Underwood and Underwood_ GERMAN FOKKER PLANE CAPTURED BY THE FRENCH]