London as well as Paris suffered from enemy bombing planes. Raid followed raid in the Spring of 1918, but the British had so improved their aerial defenses that they were able to meet the attempted ravages of the enemy with the most powerful anti-aircraft guns, which, like a wall of fire, forbade the dread monsters to come within the limits of the metropolis. Many machines in the German squadrons never got close enough to London to bomb it, but those which did let fall their terrible explosives without aim or object, killing and maiming a large number of civilians. The British were finally forced to take the only course which could have effect with the Hun. They flew into the heart of the enemy's country and gave him a taste of his own medicine. True, they chose their objectives carefully, and the targets which they bombed were munition works, railways, factories, and camps, but for all their tempered revenge they made the foe smart beneath the stinging lash that descended, again and again, upon his back. In answer to the aircraft program of the United States, Germany renewed her energies, and her construction of airplanes during the last year of the War was on a larger scale than ever before. Her small fighting machines, or speed scouts, include the _Fokker_, the _Halberstadt_, the _Roland_, the _Albatros_, the _Aviatik_, the _Pfalz_ monoplane, the _Rumpler_, the _L.V.W._ and a number of others. Some of these we have already seen at work. The _Roland_ is one of the latest types of German two-seater scouts. Every effort has been made in it to decrease the "head resistance" by careful streamlining, reduction of the number of interplane struts, etc. Swift flying and a rapid climber, it has won for itself the title of _The German Spad_. The _Pfalz_ is built either as a monoplane or as a biplane. It is a machine somewhat similar to the _Fokker_. The monoplane, however, has two machine guns, one on each side of the pilot, and firing through the propeller. Among airplanes used by the enemy for general service duties over the lines, the _A.G.O._, the _A.E.G._ and the _Gotha_ undoubtedly take the lead. All are heavily armed with machine guns and bombs and are driven by powerful motors.