In these words, a military authority of international repute indicates the war in the air which will, inevitably, take place in connection with any future European campaign.

His view is endorsed by another famous expert, who declares: "It is certain that the consequences of the use of aerial navigation will be to bring about, at the very outset of hostilities, a fight to the death between opposing aerial fleets."

The point that military authorities have come to recognise, of course, is this: if the flying machine is of vital importance to one side, it will prove equally valuable to the other. Therefore, the aim of one Commander-in-Chief will be to take steps to prevent his opponent from deriving full benefit from his aerial scouts.

Artillery-fire has been quoted, previously, as a means of combating the aeroplane, and destroying reconnoitring craft. But this method has been shown to be uncertain. What is considered a far more efficacious way of hampering the operations of an enemy’s air-scouts, is to send up machines to meet them in the air, and either drive them off, or put them out of action.

This suggests an actual contest, in mid-air, between two hostile craft; and such aerial battles are bound to occur. The most efficacious weapons, for such fighting, experience alone will indicate; but it is obvious that the ramming of one machine by another will not be resorted to. Were one aeroplane to charge an enemy’s vessel, the result would be the fall and destruction of both aircraft. Such an expedient might, of course, be resorted to as a last desperate move, say in the case where a hostile aircraft was escaping with very valuable information.

What is anticipated, in the way of a fighting aeroplane, is a machine which will carry two men, a pilot and a marksman, and be armed with some form of small quick-firing gun or rifle.

One of the experts of the French army air-corps thinks that a war aeroplane, in the immediate future, will carry a pilot, observer, and combatant. This combatant, in his opinion, should be armed with a light repeating rifle, ready to ward off the attacks of other machines.

This suggests that a reconnoitring aeroplane should be a fighting unit as well; but other views entertained are that a scouting aircraft should be accompanied by one or more fighting aeroplanes, the duties of which would be to protect it from attack.

It seems probable, in fact, that armed aeroplanes will accompany each reconnoitring machine when it is about to set out over the enemy’s position. These armed craft, or aerial cruisers, will most likely circle round the scouting machine, so as to open fire upon any hostile aeroplanes which approach.

In such an arrangement as this, the reconnoitring machine would probably be a slow-flying, reliable biplane, equipped exclusively for its work of observation. The fighting machines, on the other hand, would be built for speed. Fast-flying, strongly-built monoplanes would most likely be used; and one prominent constructer suggests that such fighting units should be fitted with a gun firing a small explosive shell, something like a "pom-pom." Such a form of armament would certainly be effective; and such an aerial cruiser is likely to prove a formidable opponent.