Q. Where is the sight placed under cases one, two, and three?
A. On the trunnion for case one, to give both elevation and direction. On the sight standard for case two, to give direction only (quadrant elevation is set by the elevating-arc). It is not intended to be used at all in case three, but, of course, it could where the quadrant elevation is to be set by the sight instead of by the elevation-arc. It will then have to be placed on the trunnions.
Q. Define cases one, two, and three.
A. Case one, where direction and elevation are given by the sight on the trunnion. Case two, where direction is given by the sight, and elevation by the quadrant or elevating-arc. Case three, where direction is given by the azimuth-circle, and elevation by the quadrant or arc.
Q. What is the difference between the axis of the bore and the line of departure?
A. The jump. (See Fig. 63.)
Q. What is the line of sight?
A. Line joining the target, the point of the front sight and the peep of the rear sight; or with telescopic sights, the line joining the target and the intersection of the vertical and horizontal hairs in the sight. (See Fig. 63.)
Q. Define time of flight.
A. The time it takes the projectile to leave the bore till it strikes.