 Artillery spotting involved firing a gun at the target, observing the projectile's point of impact (fall of shot), and correcting the aim based on where the shell was observed to land, which became more and more difficult as the range of the gun increased.Between the American Civil War and 1905, numerous small improvements were made in fire control, such as telescopic sights and optical rangefinders.There were also procedural improvements, like the use of plotting boards to manually predict the position of a ship during an engagement.