Tom,
That is cool! It is amazing that it is possible to aim at a target between 20 to 30 miles away and hit it with a bomb that weighs several thousand pounds. I think the big cannons were 16 inches in diameter. The mechanical computers certainly had to take other factors into consideration such as the yaw, pitch and roll of the ship plus wind and humidity conditions. Aiming those cannons has very little in common with aiming a rifle at a target in a shooting gallery.
david