The destructive power of The air raids was steadily lessened, however, as defensive measures were adopted and perfected. Airplane squadrons were kept in reserve at London and Paris, ready to ascend aloft at an instant's passages were constructed at various points, to which the people flocked when the alarm was given. By these measures of precaution the casualties were sensi bly lessened.
The Allies for a long time were un notice to repel the invaders. Anti aircraft guns of great range and ac curacy brought down both Zeppelins and planes. Searchlights of enormous candle power swept the skies at night in every direction. Sirens were stationed on the tops of buildings so that their shrill warnings might prompt the population to seek shelter. Bells and whistles were used for the same purpose. Underground willing to retaliate in kind. But later, as in the case of asphyxiating gases, they were forced in self-defense to adopt the same methods as the enemy, although they never attacked hospitals, as the Germans did repeatedly through the war. It was some time however before the bombing operations of the Allies rivaled those of Germany in effectiveness. The latter had organized their service to a high point of efficiency. They employed two types of planes, triplanes equipped with machine guns and au tomatic bomb throwers; the Gothas with two Mercedes engines of 260 horse power each and carrying 1,200 pounds of explosives, with gasoline sufficient for a five hours' flight, and the Fried richshafens, with two Benz motors of 225 horse power each and carrying half a ton of bombs and gasoline supplies for four hours.
By the summer of 1918, the Allies had perfected bombing planes that rivaled those of the Germans in size and power and greatly exceeded them in number. They then began a system
of reprisals over the cities of the Rhine valleys, selecting as their targets muni tion factories, railway sidings, bar racks, and steel works. Despite their efforts to limit their targets, much damage was done inevitably to civilian property and considerable loss of life resulted in Coblenz, Diisseldorf, Cologne, and other cities. In a three months' period, 249 raids were made and 247 tons of bombs dropped. So heavy was airplanes. Propaganda was also tered over the enemy's lines. Millions of pamphlets and leaflets fluttered down the damage inflicted that the German Government on Nov. 4 appealed to the American Government, and proposed the abandonment by both sides of attacks into enemy trenches, and told to the soldiers there the views of the other side and the course that operations were taking. This was done by both sides, on cities outside of the fighting zone. What it had itself originated was prov ing its undoing.
Not only bombs were dropped from and in the later days of the war proved especially useful to the Allies, as was proved by the bitterness of Hinden burg's complaint of the demoralization thus produced among his troops. Earlier than this, the Italian poet-aviator d'Annunzio had flown over the Alps to Sienna and circled over that city, tragic poet. Of 90 plays produced by him, 40 were rewarded with the public prize, but only seven have come down to us, though the titles of 72 others are dropping pamphlets which told the Viennese that he could just as easily have dropped bombs and urged them to withdraw from a hopeless conflict.