The entire science of aerial fighting has developed, as everyone knows, since the beginning of this war, in other words in the short space of four years.

To–night I am going to attempt to give you an outline of the various stages through which aerial fighting has progressed to its present state of efficiency, though it would be foolish to claim that we have even begun to realise the methods and tactics which will be employed in the future.

All through the history of aerial fighting we find two main governing factors, and I would ask you to notice how these affect each step. These two factors are:—

1. (1) Field of fire.

2. (2) Field of view.

In talking of the latter, I shall be constantly mentioning blind spots. By a blind spot is meant anywhere in the sky which is hidden by the planes, tail or fuselage, from the pilot as he sits in his cockpit.