Some of these fights last ten, some fifteen minutes.

When the weather allows flights, there ought always to be several battle-planes in the air to protect the other kinds of airplanes.

One must lay down as a rule, and we here repeat the opinion expressed by famous aviators, that every attack, whether by a single machine or by a squadrilla, must always be carried out with the utmost vigour. The Germans seem, indeed, to have received orders to fly away whenever they feel themselves inferior.

An important function of the battle-planes is to escort and protect the scouting or raiding squadrons during their operations, so as to allow the latter to fulfil their mission without having to guard against any possible attack of the enemy.

During these expeditions the battle-plane is to the other airplanes what the destroyers are to the ships they convoy. In order that they may afford efficient protection to the ships, the destroyers must be very fast and manageable; likewise the chasing airplanes must of necessity be more rapid and manageable than those they are sent to protect.

Bombing-Planes. The number of machines composing a squadrilla of bombardment varies. Several squadrillas often start together to accomplish a mission, forming an aërial army. The machines thus detailed must be able to carry a heavy load of ammunition, also a provision of gasoline sufficient to allow them to remain a long time in the air.

To realize the progress made in the construction of such machines one has but to remember that, on the 15th of last October, an Italian airplane carrying a great weight in addition to its supply of gasoline, covered the distance from Turin to the English coast in ten hours.

The Italians have now at Washington a machine carrying twelve persons. All the Powers are building large airplanes intended to make bombardments more and more deadly.

At first, ordinary bombs were dropped from airplanes, but they are now supplied with special bombs filled with the most powerful explosives known (winged torpedoes), and also incendiary and asphyxiating projectiles. Special devices have been constructed which increase the accuracy of the aim, when dropping bombs.

These bombing-planes are armed with quick-firing guns, but are less handy and manageable than the battle-plane, whose protection, therefore, they require.