One of the lessons of these true aerial battles between opposing squadrons has been the efficiency of the biplane, as compared with that of the monoplane. When the war started the monoplane was considered the machine par excellence for war use; its high speed and quick maneuvering being cited as most important for fighting in the air. Eighteen months of aerial battles have shown that for all-round fighting, bombing and reconnoitering the biplane is far more effective, and the construction of new monoplanes has been practically abandoned by the allied governments. The Germans, it is true, have found the Fokker type of monoplane a very efficient one, but the number of Fokkers in use is comparatively small, when the great fleets of Aviatiks and other well-known types of German biplanes are remembered. Exact statistics regarding the number of aeroplanes at present in use along the various battle fronts are not available, but estimates made by aviation officers, by correspondents and from notes in the respective publications devoted to aviation abroad, fix it as in excess of 12,000 machines. More than half of these are used by the Allies on the western front; Germany is credited with 3,000 aeroplanes, Russia with about 1,000, Austria with 1,500, and Bulgaria and Turkey with 500. In a statement made in the British House of Commons, Mr. Tennant, speaking of the Royal British Flying Corps, declared that 835 officers and 521 civilians were on the waiting list of the Flying Corps in the last week of February, 1916. France has definitely discontinued the use of monoplanes and is manufacturing them solely for the British forces, as some of the British aviators greatly prefer the monoplane. One of the reasons given by the French for their action is the construction of Fokker monoplanes by the Germans, which are so accurate a copy of the earlier Morane monoplanes of the French that they could not be distinguished from them in the air. Furthermore, the German copy of the Morane was far speedier and could easily outdistance or overtake the French machines of the same type. In place of the original Morane France now has three types of speed planes, the Maurice Farman, a 110 mph. biplane, the Morane-Saulnier, 111 mph., and Spad, 107 mph. The older Nieuports, too, are fast machines, being capable of more than 100 miles per hour.