For some time the solution of the forward speed of an aeroplane seemed impracticable. It has now been solved by the simple use of a telescope, mounted on a gimbal so as to maintain its horizontal position and movable vertically along a graduated arc. By setting the telescope to read an angle of forty-five degrees and snapping a stop watch on an object which lies in the line of sight of the telescope produced, and then swinging the telescope so as to point vertically downward, we can, by snapping the stop watch a second time as the sighting point again comes into the field of vision, ascertain the exact time it has taken the machine to cover the distance measured by forty-five degrees of arc. Our altitude is known by reading a barometer. We then have two known angles of a right triangle and one known side, viz., the altitude. By a set of tables, already made out, we can determine our forward speed. Now, all of this is done as a preliminary to actually dropping the projectile. After we have the forward speed and the altitude we simply consult another set of previously prepared tables and read from those tables an angle. This angle shows the proper point of drop to hit another point on the ground somewhere in advance of the aeroplane. After picking the angle out of the table we set our telescope to read the known angle and, when the line of sight, produced, is on the objective, we release or "trip" the projectile. This has actually been done. Now I ask you the question, can an aeroplane be used to kill the other fellow? Can an aeroplane be used to prevent the other fellow from killing us? Of course it is much superior to Santa Ana's mule for purposes of rapid departure from the scene of hostilities, but that is hardly the test we apply. It is, on the other hand, inferior as a shield to the ordinary breastworks constructed by armies in the field, but, again, that is not precisely the test to be applied. The most effective way in which we can keep the other fellow from killing us is to find out where he is, what he is doing and how he proposes to accomplish his–to us reprehensible, to him laudable–object. Accordingly we apply the information test to the aeroplane. Can we use it to gather information of the enemy, his lines of communication, his lines of defences, his probable lines of advance or retreat, his rail and water communications, his artillery positions and gun emplacements, and a host of other things, all of which tend to produce success or failure in battle? In other words, can we use the aeroplane to prevent the enemy from killing us? In order to make use of information there are two distinct steps which must be taken: First, it must be gathered; second, it must be communicated to the proper officers for transmission to the Commanding General in the field. No information is of value until it is communicated to an officer competent to act upon it.